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Modulating Pt surfaces through the introduction of lattice distortion emerges as immensely effective strategy that enhances the kinetics of alkaline hydrogen evolution and oxidation processes. In this study, we fabricated lattice-distorted Pt wrinkled nanoparticles (LD-Pt WNPs) for efficient hydrogen electrocatalysis. The LD-Pt WNPs not only outperform the Pt/C benchmark in hydrogen oxidation reaction, achieving an excellent mass-specific current of 968.5 mA·mgPt−1 (9 times that of Pt/C), but also demonstrate outstanding hydrogen evolution reaction activity with a small overpotential of 58.0 mV. Comprehensive experiments and density functional theory calculations reveal that lattice defects introduce an abundance of unsaturated coordination atoms while modifying the d-band center of Pt. This dual effect optimizes the binding strength of crucial H and OH intermediates, leading to a significant reduction in the energy barrier of the reaction bottleneck, commonly known as the Volmer step. This work unveils a fresh viewpoint on projecting and developing high efficiency electrocatalysts through defect engineering. [ABSTRACT FROM AUTHOR]

Enhancing catalytic activity through modulating the interaction between N-doped carbon and metal phosphides clusters is an effective approach. Herein, the electronic structure modulation of CoP2 supported N-modified carbon (CoP2/NC) has been designed and prepared as efficient electrocatalysts for oxygen reduction reaction (ORR), oxygen evolution reaction (OER), and hydrogen evolution reaction (HER). Notably, CoP2/NC-1 catalyst exhibits impressive performance in alkaline media, with an ORR half-wave potential of 0.84 V, as well as OER and HER overpotentials of 290 and 129 mV (at 10 mA·cm−2), respectively. In addition, CoP2/NC-1 produces a power density as high as 172.9 mW·cm−2, and excellent reversibility of 100 h at 20 mA·cm−2 in home-made Zn-air batteries. The experimental results demonstrate that the synergistic interactions between N modified carbon substrate and CoP2 material significantly enhance the kinetics of ORR, OER, and HER. Density functional theory (DFT) calculations reveal the strong electrons redistribution of CoP2 induced by high-density N atoms at the interface, thus optimizing the key intermediates and significantly lower the energy barrier of reactions. These electronic adjustments of CoP2 greatly enhance its kinetics of ORR/OER/HER, leading to faster reactions. This study provides profound insights into the specific modification of CoP2 by N-doped carbon, enabling the construction of efficient catalysts. [ABSTRACT FROM AUTHOR]

Exogenous variables, unrelated to the recommendation system itself, can significantly enhance its performance. Therefore, integrating these time-evolving exogenous variables into a time series and conducting time series predictions can maximize the potential of recommendation systems. We refer to this task as Time Series Prediction Empowering Recommendations (TSPER). However, as a subtask within the recommendation system, TSPER faces unique challenges such as computational and data constraints, system evolution, and the need for performance and interpretability. To meet these unique needs, we propose a lightweight Multi-Layer Perceptron architecture with joint Time-Frequency information, named Light All-MLP with joint TimE-frEquency information (LAMEE). LAMEE utilizes a lightweight MLP architecture to achieve computing efficiency and adaptive online learning. Moreover, various strategies have been employed to improve the model, ensuring stable performance and model interpretability. Across multiple time series datasets potentially related to recommendation systems, LAMEE balances performance, efficiency, and interpretability, overall surpassing existing complex methods. [ABSTRACT FROM AUTHOR]

The development of rapid and accurate assays is crucial to prevent the rapid spread of highly contagious respiratory infections such as coronavirus (COVID-19). Here, we developed a surface-enhanced Raman scattering (SERS)–enzyme-linked immunosorbent assay (ELISA) method that allows for the screening of multiple patient samples with high sensitivity on a 1536-well plate. As the well number on the ELISA well plate increases from 96 to 1536, the throughput of the assay increases but the sensitivity decreases due to the low number of biomarkers and the increase in non-specific binding species. To address this problem, silica (SiO2) beads were used to increase the surface-to-volume ratio and the loading density of biomarkers, thereby enhancing sensitivity. Using a three-dimensional gold nanoparticle (AuNP)@SiO2 SERS assay platform on a 1536-well plate, an immunoassay for the nucleocapsid protein biomarker of SARS-CoV-2 was performed and the limit of detection (LoD) decreased from 273 to 7.83 PFU/mL compared to using a two-dimensional assay platform with AuNPs. The proposed AuNPs@SiO2 SERS immunoassay (SERS-IA) platform is expected to dramatically decrease the false-negative diagnostic rate of the currently used lateral flow assay (LFA) or ELISA by enabling the positive diagnosis of patients with low virus concentrations. [ABSTRACT FROM AUTHOR]

Invertase is the key enzyme involved in several crucial biological processes by hydrolyzing sucrose for production of glucose and fructose. Invertase plays important roles in the fields of food, pharmacy, cosmetics, biofuels, and agriculture. Detection of invertase activity is urgently necessary for scientific research and industrial processes. Herein, a continuous fluorometric method was developed for real-time detection of invertase activity. 8-Isoquinolinylboronic acid responded to fructose by formation of a fluorescent complex in turn-on manner, and served as a fluorescent sensor to selectively recognize fructose in ternary enzymatic mixture containing sucrose and glucose. The limit of detection (LOD) for fructose was 0.07 mM. Progress curve for fructose production was established by directly and continuously monitoring the fluorescence for invertase reaction with sucrose as substrate. Initial velocity was obtained to characterize invertase activity. LOD for invertase assay was 0.10 U·mL−1. Km and υmax for invertase were determined as 7.70 mM and 0.86 mM·min−1, respectively. Copper ion was demonstrated to inhibit the invertase activity with IC50 of 33.61 mM. Applicability in high-throughput screening for inhibitor was demonstrated. The proposed method allows for real-time, simple, and rapidly monitoring the invertase activity. It has a broad range of potential applications for kinetics and screening inhibitor. [ABSTRACT FROM AUTHOR]

Defensive behaviors induced by innate fear or Pavlovian fear conditioning are crucial for animals to avoid threats and ensure survival. The zona incerta (ZI) has been demonstrated to play important roles in fear learning and fear memory, as well as modulating auditory-induced innate defensive behavior. However, whether the neuronal subtypes in the ZI and specific circuits can mediate the innate fear response is largely unknown. Here, we found that somatostatin (SST)-positive neurons in the rostral ZI of mice were activated by a visual innate fear stimulus. Optogenetic inhibition of SST-positive neurons in the rostral ZI resulted in reduced flight responses to an overhead looming stimulus. Optogenetic activation of SST-positive neurons in the rostral ZI induced fear-like defensive behavior including increased immobility and bradycardia. In addition, we demonstrated that manipulation of the GABAergic projections from SST-positive neurons in the rostral ZI to the downstream nucleus reuniens (Re) mediated fear-like defensive behavior. Retrograde trans-synaptic tracing also revealed looming stimulus-activated neurons in the superior colliculus (SC) that projected to the Re-projecting SST-positive neurons in the rostral ZI (SC-ZIrSST-Re pathway). Together, our study elucidates the function of SST-positive neurons in the rostral ZI and the SC-ZIrSST-Re tri-synaptic circuit in mediating the innate fear response. [ABSTRACT FROM AUTHOR]

Leguminous plants form root nodule organs with soil rhizobia bacteria, which can fix atmospheric nitrogen (N2) and supply ammonia to the host plant. It is established that the symbiotic N fixation efficiency is substantially influenced by plant nutrients, such as molybdenum (Mo), phosphorus (P), copper (Cu), and zinc (Zn). Potassium (K+) is the most abundant cation in plant cells; however, little evidence regarding the potential link between K nutrition and symbiotic N fixation efficiency is available to date. Here, we showed that K+ deficiency reduced the efficiency of symbiotic nitrogen fixation, and inoculated with rhizobia strain USDA110 could improve plant K+ acquisition. Furthermore, we identified a potassium transporter gene (GmHAK5) that was highly expressed in the root steles and in the vasculature cells of nodules. The GmHAK5 protein was localized at the plasma membrane and could rescue the growth phenotype of yeast K+ uptake-defective mutant. The results obtained from this study provides new insights for the understanding of the potential role of K+ nutrition in modulating symbiotic N fixation in soybean. [ABSTRACT FROM AUTHOR]

Noble metal electrocatalysts (e.g., Pt, Ru, etc.) suffer from sluggish kinetics of water dissociation for the electrochemical reduction of water to molecular hydrogen in alkaline and neutral pH environments. Herein, we found that an integration of Ru nanoparticles (NPs) on oxygen-deficient WO3-x manifested a 24.0-fold increase in hydrogen evolution reaction (HER) activity compared with commercial Ru/C electrocatalyst in neutral electrolyte. Oxygen-deficient WO3-x is shown to possess large capacity for storing protons, which could be transferred to the Ru NPs under cathodic potential. This significantly increases the hydrogen coverage on the surface of Ru NPs in HER and thus changes the rate-determining step of HER on Ru from water dissociation to hydrogen recombination. While water splitting electrolysis offers an appealing means to produce H2 fuel, catalysts show sluggish reaction rate in neutral media. Here, authors utilize hydrogen spillover from oxygen-deficient tungsten oxides to Ru nanoparticles to boost the neutral-pH H2 evolution performances. [ABSTRACT FROM AUTHOR]

Focal cortical dysplasia (FCD) is one of the most common causes of drug-resistant epilepsy. Dysmorphic neurons are the major histopathological feature of type II FCD, but their role in seizure genesis in FCD is unclear. Here we performed whole-cell patch-clamp recording and morphological reconstruction of cortical principal neurons in postsurgical brain tissue from drug-resistant epilepsy patients. Quantitative analyses revealed distinct morphological and electrophysiological characteristics of the upper layer dysmorphic neurons in type II FCD, including an enlarged soma, aberrant dendritic arbors, increased current injection for rheobase action potential firing, and reduced action potential firing frequency. Intriguingly, the upper layer dysmorphic neurons received decreased glutamatergic and increased GABAergic synaptic inputs that were coupled with upregulation of the Na+-K+-Cl− cotransporter. In addition, we found a depolarizing shift of the GABA reversal potential in the CamKII-cre::PTENflox/flox mouse model of drug-resistant epilepsy, suggesting that enhanced GABAergic inputs might depolarize dysmorphic neurons. Thus, imbalance of synaptic excitation and inhibition of dysmorphic neurons may contribute to seizure genesis in type II FCD. [ABSTRACT FROM AUTHOR]

Nitrocellulose (NC) membranes, as porous paper-like substrates with high protein-binding capabilities, are very popular in the field of point-of-care immunoassays. However, generating robust hydrophobic structures in NC membranes to fabricate microfluidic paper-based analytical devices (μPADs) remains a great challenge. At present, the main method relies on an expensive wax printer. In addition, NC membranes very easy to adhere during the printing process due to electrostatic adsorption. Herein, we developed a facile, fast and low-cost strategy to fabricate μPADs in NC membranes by screen-printing polyurethane acrylate (PUA) as a barrier material for defining flow channels and reaction zones. Moreover, hydrophobic barriers based on UV-curable PUA can resist various surfactant solutions and organic solvents that are generally used in immunoassays and biochemical reactions. To validate the feasibility of this PUA-based NC membrane for immunoassays in point-of-care testing (POCT), we further designed and assembled a rotational paper-based analytical device for implementing a multiplexed enzyme-linked immunosorbent assay (ELISA) in a simple manner. Using the proposed device under the optimal conditions, alpha fetoprotein (AFP) and carcinoembryonic antigen (CEA) could be identified, with limits of detection of 136 pg/mL and 174 pg/mL, respectively, which are below the threshold values of these two cancer biomarkers for clinical diagnosis. We believe that this reliable device provides a promising platform for the diagnosis of disease based on ELISA or other related bioassays in limited settings or remote regions. [ABSTRACT FROM AUTHOR]

The toxic effect of di(2-ethylhexyl) phthalate (DEHP) on prepubertal testes was examined in this study. We treated 3-week-old male mice with 4.8 mg/kg/day (milligram/kilogram/day) (no observed adverse effect level), 30 mg/kg/day (high exposure dose relative to humans), 100 mg/kg/day (level causing a reproductive system disorder), and 500 mg/kg/day (dose causing a multigenerational reproductive system disorder) of DEHP via gavage. Obvious abnormalities in the testicular organ coefficient, spermatogenic epithelium, and testosterone levels occurred in the 500 mg/kg DEHP group. Ribonucleic acid sequencing (RNA-seq) showed that differentially expressed genes (DEGs) in each group could enrich reproduction and reproductive process terms according to the gene ontology (GO) results, and coenrichment of metabolism pathway was observed by the Reactome pathway analysis. Through the analysis of common genes in the metabolism pathway, we discovered that DEHP exposure at 4.8 to 500 mg/kg or 100 mg/kg caused the same damages to the prepubertal testis. In general, we identified two key transcriptional biomarkers (fatty acid binding protein 3 (Fabp3) and carboxylesterase (Ces) 1d), which provided new insight into the gene regulatory mechanism associated with DEHP exposure and will contribute to the prediction and diagnosis of prepuberty testis injury caused by DEHP. [ABSTRACT FROM AUTHOR]

High entropy alloys (HEAs) contain near equimolar amounts of five or more elements and are a compelling space for materials design. In the design of HEAs, great emphasis is placed on identifying thermodynamic conditions for single-phase and multi-phase stability regions, but this process is hindered by the difficulty of navigating stability relationships in high-component spaces. Traditional phase diagrams use barycentric coordinates to represent composition axes, which require (N – 1) spatial dimensions to represent an N-component system, meaning that HEA systems with N > 4 components cannot be readily visualized. Here, we propose forgoing barycentric composition axes in favor of two energy axes: a formation-energy axis and a 'reaction energy' axis. These Inverse Hull Webs offer an information-dense 2D representation that successfully captures complex phase stability relationships in N ≥ 5 component systems. We use our proposed diagrams to visualize the transition of HEA solid-solutions from high-temperature stability to metastability upon quenching, and identify important thermodynamic features that are correlated with the persistence or decomposition of metastable HEAs. [ABSTRACT FROM AUTHOR]

The responses of wheat yield to large-scale atmospheric circulation indices (LACI) were explored in Henan province, north China. With using the annual series of climate-driven yield index (CDYI) extracted from winter wheat yield collected in 17 cites and the monthly series of 15 types of LACI during 1988–2017, the main findings were as follows: (1) this province could be divided into four sub-regions (central-east, west, north, and south Henan) with different CDYI variations; (2) the CDYI in central-east, west, south Henan was dominated by a 3-year oscillation, while the CDYI in north Henan presented a notable 7.5-year oscillation; (3) among the four sub-regions, central-east Henan had the most significant CDYI-LACI relationship, and the higher Nino 1 + 2 in December were a key yield reduction signal; (4) during 2008–2017, the stronger increase of Nino1 + 2_in December had caused the yield decrease in central Henan by 6.58%. In summary, linking wheat yield to LACI anomalies should be instrumental in alleviating the adverse effects of climate change on wheat production. [ABSTRACT FROM AUTHOR]

MgxZn1−xO (x = 0.05, 0.10, 0.15, and 0.20) films prepared on quartz substrates by the sol–gel method were characterized and studied. According to scanning electron microscopy and x-ray diffraction data, the MgxZn1−xO films exhibited a particle-stacking morphology and a hexagonal wurtzite crystal structure. An increase in Mg content led to an obvious increase in particle size. However, a weakening of the hexagonal wurtzite structure was observed and indicated the transition of the MgxZn1−xO crystal structure, which was also confirmed by the Raman spectra results. An increase in bandgap energy from 3.38 eV to 3.55 eV with increased Mg content was determined from the transmittance spectra. Ultraviolet photodetectors based on MgxZn1−xO with interdigital electrodes were then fabricated. Dark current as low as 10 pA (corresponding to 5 nA/cm2) under bias of 10 V was achieved. A blueshift of the peak wavelength and cutoff wavelength was observed with increasing Mg content. Noise equivalent power as low as 2 × 10−15 W was achieved, detectivity was found to be about 1.2 × 1011 cm Hz1/2/W, and quantum efficiency was nearly 100%, which was related to the photoconductive gain. [ABSTRACT FROM AUTHOR]

Primary age-related tauopathy (PART) is characterized by tau neurofibrillary tangles (NFTs) in the absence of amyloid plaque pathology. In the present study, we analyzed the distribution patterns of phosphorylated 43-kDa TAR DNA-binding protein (pTDP-43) in the brains of patients with PART. Immunohistochemistry and immunofluorescence double-labeling in multiple brain regions was performed on brain tissues from PART, Alzheimer's disease (AD), and aging control cases. We examined the regional distribution patterns of pTDP-43 intraneuronal inclusions in PART with Braak NFT stages > 0 and ≤ IV, and a Thal phase of 0 (no beta-amyloid present). We found four stages which indicated potentially sequential dissemination of pTDP-43 in PART. Stage I was characterized by the presence of pTDP-43 lesions in the amygdala, stage II by such lesions in the hippocampus, stage III by spread of pTDP-43 to the neocortex, and stage IV by pTDP-43 lesions in the putamen, pallidum, and insular cortex. In general, the distribution pattern of pTDP-43 pathology in PART cases was similar to the early TDP-43 stages reported in AD, but tended to be more restricted to the limbic system. However, there were some differences in the distribution patterns of pTDP-43 between PART and AD, especially in the dentate gyrus of the hippocampus. Positive correlations were found in PART between the Braak NFT stage and the pTDP-43 stage and density. [ABSTRACT FROM AUTHOR]

Inspired by the excellent activity of platinum in hydrogen evolution reaction (HER) and the good performance of Ni-based compounds in oxygen evolution reaction (OER), a bifunctional electrocatalyst PtNi carbon nanofiber (CNF) is designed and fabricated using electrospinning followed by carbonization. Ultra-small PtNi nanoparticles of several nanometers in size are densely dispersed on every CNF, along with a few larger nanoparticles with sizes of several decades of nanometers. The as-prepared catalysts can be directly used as an electrode and act as high-efficiency materials for water splitting, including HER and OER. For HER activity, the PtNi/CNFs reach 10 mA cm current density at low overpotentials of 34 mV and exhibit a small Tafel slope of 31 mV dec in acidic electrolytes of 0.5 M HSO, which is close to that of commercial Pt/C (20 wt%) electrocatalytic catalysts. In 1 M KOH solution, the PtNi/CNFs also exhibit excellent HER activity with a low overpotential of 82 mV to achieve a current density of 10 mA cm and a small Tafel slope of 34 mV dec. Moreover, the PtNi/CNFs also show good activity for OER in alkaline electrolyte of 1 M KOH with a Tafel slope of 159 mV dec and a small overpotential of 151 mV to reach a current density of 10 mA cm. In addition, the OER performance of the PtNi/CNFs in acid media is also favorable, with a 198 mV dec Tafel slope. The decent activity of the PtNi/CNFs for water splitting originates from the synergistic effects of using Pt and Ni, large amounts of ultra-small nanoparticles densely dispersed on the CNFs, high conductivity of the support materials and interconnected three-dimensional structures of the carbon nanofiber mats. [ABSTRACT FROM AUTHOR]

In plants, the plasma membrane H-ATPase (HA) is considered to play a crucial role in regulating plant growth and respoding to environment stresses. Multiple paralogous genes encoding different isozymes of HA have been identified and characterized in several model plants, while limited information of the HA gene family is available to date for tomato. Here, we describe the molecular and expression features of eight HA-encoding genes ( SlHA1-8) from tomato. All these genes are interrupted by multiple introns with conserved positions. SlHA1, 2, and 4 were widely expressed in all tissues, while SlHA5, 6, and 7 were almost only expressed in flowers. SlHA8, the transcripts of which were barely detectable under normal or nutrient-/salt-stress growth conditions, was strongly activated in arbuscular mycorrhizal (AM) fungal-colonized roots. Extreme lack of SlHA8 expression in M161, a mutant defective to AM fungal colonization, provided genetic evidence towards the dependence of its expression on AM symbiosis. A 1521-bp SlHA8 promoter could direct the GUS reporter expression specifically in colonized cells of transgenic tobacco, soybean, and rice mycorrhizal roots. Promoter deletion assay revealed a 223-bp promoter fragment of SlHA8 containing a variant of AM-specific cis-element MYCS (vMYCS) sufficient to confer the AM-induced activity. Targeted deletion of this motif in the corresponding promoter region causes complete abolishment of GUS staining in mycorrhizal roots. Together, these results lend cogent evidence towards the evolutionary conservation of a potential regulatory mechanism mediating the activation of AM-responsive HA genes in diverse mycorrhizal plant species. [ABSTRACT FROM AUTHOR]

WRKY transcription factors play important roles in various stress responses in diverse plant species. In cotton, this family has not been well studied, especially in relation to fiber development. Here, the genomes and transcriptomes of Gossypium raimondii and Gossypium arboreum were investigated to identify fiber development related WRKY genes. This represents the first comprehensive comparative study of WRKY transcription factors in both diploid A and D cotton species. In total, 112 G. raimondii and 109 G. arboreum WRKY genes were identified. No significant gene structure or domain alterations were detected between the two species, but many SNPs distributed unequally in exon and intron regions. Physical mapping revealed that the WRKY genes in G. arboreum were not located in the corresponding chromosomes of G. raimondii, suggesting great chromosome rearrangement in the diploid cotton genomes. The cotton WRKY genes, especially subgroups I and II, have expanded through multiple whole genome duplications and tandem duplications compared with other plant species. Sequence comparison showed many functionally divergent sites between WRKY subgroups, while the genes within each group are under strong purifying selection. Transcriptome analysis suggested that many WRKY genes participate in specific fiber development processes such as fiber initiation, elongation and maturation with different expression patterns between species. Complex WRKY gene expression such as differential D and A allelic gene expression in G. hirsutum and alternative splicing events were also observed in both diploid and tetraploid cottons during fiber development process. In conclusion, this study provides important information on the evolution and function of WRKY gene family in cotton species. [ABSTRACT FROM AUTHOR]