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A homogeneous electrochemical deposition method was used in this study of CdAl nanoparticles onto CP fibers at −1.1, −1.2, −1.3, and −1.4 V vs. RHE to prepare highly active, selective, and stable CdAl-LDHs nanocatalysts. The electrochemically deposited materials exhibited extremely high CO selectivity during CO 2 RR, with the CO FE reaching 99.71% at −1.6 V vs. RHE and a partial current density of 22.13 mA cm−2. The CdAl-LDHs maintained excellent CO FE along with high CO partial current density. Remarkably, the CdAl-LDHs demonstrated outstanding electrochemical performance that exceeded most of the reported CO 2 reduction to CO electrocatalysts, maintaining stable electrocatalytic performance for more than 30 h with the FE remaining stable at about 99% and a current density at 10.05 mA cm−2 with little decay. [Display omitted] • CdAl nanoparticles with high activity, selectivity and stability were directly deposited on CP fibers by electrochemical deposition method. • The materials prepared by electrochemical deposition exhibit extremely high CO selectivity in the CO 2 RR process, with Faraday efficiency up to 99.71 %. • CdAl-LDHs can maintain the electrocatalytic performance for more than 30 h, and in this process, and the Faraday efficiency can be stable at about 99 %. Layered bimetallic hydroxides are at the forefront of current research in electrocatalytic materials. Although there is considerable research on various bimetallic hydroxides, the study of bimetallic hydroxides for electrocatalytic reduction of carbon dioxide is limited. In this paper, cadmium-aluminum layered bimetallic hydroxide nanoparticles (CdAl-LDHs) were prepared using a simple electrochemical deposition method. The prepared CdAl-LDHs was characterized in detail, and its potential application as an electrocatalyst was discussed. CdAl-LDHs prepared using different methods showed different selectivity in the electrocatalytic reduction of CO 2 to CO. The nanomaterial exhibits excellent CO selectivity in a reaction chamber using 2 %-BMIM(PF 6)(1-butyl-3-methylimidazolium hexafluorophosphate)/DMF(N-N dimethyl formamide) as the electrolyte. The CdAl-LDHs prepared by electrochemical deposition exhibited a maximum CO partial current density of 22.13 mA cm−2 with a remarkable CO Faraday efficiency (FE) of 99.71 %, which is comparable to or even higher than that of noble metal catalysts. This high selectivity for CO indicates its potential as an alternative to expensive noble metal catalysts. Moreover, the catalyst demonstrated high stability over 30 h of continuous operation with stable FE of around 99 % and a current density of around 10.5 mA cm−2, with minimal degradation during the entire reaction cycle. In addition, the catalyst showed a low HER current density of less than 0.1 mA cm−2 at all tested potentials, indicating that the catalyst maintains a high level of CO 2 conversion over the entire range of tested potentials. This suggests its great potential for industrial applications. [ABSTRACT FROM AUTHOR]

With the increasing pressure on the National Institutes of Health (NIH) budget nowadays, it is such a major challenge to cut waste and improve efficiency in the research funding allocation. To meet this challenge, this paper explores research hotspots and disciplinary trends of the biomedical area, and discusses the relationship between these factors and the government funding, thereby uncovering biomedical hotspots of interest to academia and the evolution law of the U.S. federal government funding through an entitymetrics analysis. Considering that the rapid proliferation of biomedical literature provides large amounts of information resources for knowledge discovery, entities extracted from articles in PubMed and NIH-funded projects during 1988–2017 are taken as experimental data. They are divided into four categories: species, diseases, genes, and drugs. Subsequently, a comparative analysis of entity trajectories in the four domains is performed, which includes occurrence frequency calculations of disease entities to explore frequency variation trends in high-frequency entities and the situation of the distribution of research funds. Finally, we conduct an evolutionary analysis of two sides, respectively: the relationship between research popularity and the amount of funding; the relationship between research popularity and the number of funded projects. The results suggest that research on gene and disease entities is at the stage of rapid development. Diseases with high prevalence rate and mortality and diseases associated with genetic factors will be the emphasis of research trends in the future. The distribution of NIH grant appears obvious long tail effect and can influence overall trends in the heat of research topics.. We also find that there is a strong linear correlation between the research popularity of bio-entities, and the amount and number of funding grants, respectively. However, the impact of the amount and number of grant funds on the entity research popularity is decreasing. The above results indicate the extensive applicability of entitymetrics in funding research. [ABSTRACT FROM AUTHOR]

Of late, various constitutive models have been proposed in the literature for the purpose of capturing the various complex physical mechanisms governing the creep behavior of soft soil. However, the more complex the model, the greater the number of associated uncertain parameters it has, and the less robustness it is. In this study, the Bayesian model class selection approach is applied to select the most plausible/suitable model describing the creep behavior of soft soil using laboratory measurements. In total, one elastic plastic (EP) model and eight elastic viscoplastic (EVP) models are investigated. To assess the performance of the different models in the prediction of creep behavior of soft soils, Bayesian model class selection is respectively performed using the oedometer test data from the intact samples of Vanttila clay and reconstituted samples of Hong Kong Marine Clay collected from the literature. All unknown model parameters are identified simultaneously by adopting the transitional Markov Chain Monte Carlo (TMCMC) method, and their uncertainty is quantified through the obtained posterior probability density functions (PDFs). The result shows that the proposed method is an excellent candidate for identifying the most plausible model and its associated parameters for different kinds of soft soils. The approach also provides uncertainty evaluation of the model prediction based on the given data. [ABSTRACT FROM AUTHOR]

[Display omitted] • A novel strategy through strong metal-support interaction and incorporation of Er was proposed. • Monodisperse MoO 2 /Mo 2 N 3 clusters were synthesized by supramolecular-confinement pyrolysis. • Hollow capsules structure and graphitic carbon accelerate electron and mass transfer. • Er-MoO 2 /Mo 2 N 3 @P,NC shows high efficiency electrocatalytic and structural stability during HER. The realization of a hydrogen-based economy with robust hydrogen evolution reaction catalysts remains a challenge. In this study, we prepared MoO 2 /Mo 2 N 3 heterostructure nanoclusters co-doped with nitrogen, phosphorus, and erbium for the first time. The introduction of the nitrogen and phosphorus atoms into the transition metal increases the d-electron density and contracts the d-band, which leads to a rearranged electronic structure of the MoO 2 /Mo 2 N 3 heterojunction. The coupling of the rare earth erbium dopant with the valence band of the heterojunction leads to the redistribution of the electron density in the catalyst and promotes covalent interaction with the adsorbed intermediates, thereby optimizing the Gibbs free energy of intermediate adsorption and improving the catalytic activity for the hydrogen evolution reaction. Not only is an efficient and economical catalyst for electrolytic aquatic hydrogen production provided in this work, but a new synthesis scheme is also proposed for the rational synthesis of homologous core–shell polymetallic nanostructures with broad application prospects. [ABSTRACT FROM AUTHOR]

Abstract: A new organically modified silicate (ormosil) material was synthesized as a matrix to encapsulate enzyme labeled antibody for preparation of immunosensors. The ormosil matrix was prepared by hydrolyzing tetraethyoxysilane and (3-aminopropyl)triethoxysilane in weak alkali solution. It possessed three-dimensional ordered nanoporous structure with high electrical conductivity and good mechanical stability. Its hydrophilicity provided a microenvironment for retaining the biological activity of the immobilized protein. Particularly, using horseradish peroxidase-labeled human chorionic gonadotrophin antibody (HRP-anti-hCG) as a model, the immobilized HRP showed direct electron transfer at about −35mV with a rate constant of 15.8±3.8s−1. By a simple one-step immunoreaction between human serum chorionic gonadotrophin (hCG) in sample solution and the immobilized HRP-anti-hCG, the differential pulse voltammetric peak current of HRP decreased linearly with an increasing hCG concentration from 0.5 to 50mIU/ml with a relatively low limit of detection of 0.3mIU/ml at 3σ. Excellent analytical performance, fabrication reproducibility and operational stability of the proposed biosensor indicated its promising application in clinical diagnostics. [Copyright &y& Elsevier]

Jet grouting column is widely used in ground improvements of hydraulic and geotechnical structures. Estimation of the diameter of the jet grouting column is indispensable to the design of those structures. Existing prediction models of the jet grouting column perform poorly when applied to the recently emerged double and triple-jet grouting systems and cannot quantify the prediction uncertainties. This study has compiled a global-wide jet grouting database and proposed an explicit model that is suitable for all three popular jet grouting systems (i.e., single, double, and triple). The Bayesian inference method was employed to estimate the regression parameters for the proposed model and quantify the prediction uncertainty. The proposed model is compared with a widely used empirical model through a cross-validation procedure. The comparisons show the proposed model is free of systematic errors and has much higher accuracy than the existing method, although the two have similar complexities in terms of the number of unknown regression parameters. The new model can reasonably quantify the prediction uncertainty in the sense that the 95% confidence interval of jet grouting column diameter covers the actual value with a probability of around 95%. To facilitate practice use, analytical formulas have been derived to calculate the statistics of jet grouting column diameter. This unique feature developed here to quantify the prediction uncertainty provides a potentially fundamentally new tool for engineers to estimate the jet grouting column diameter and assess the associated prediction errors. [ABSTRACT FROM AUTHOR]

The hybrid water electrolysis affords a green route for the generation of fine chemicals accompanied with hydrogen production relying on the rapid development of anodic electrocatalysts. Herein, a nickel‐cobalt layered double hydroxide (Ni Co LDH) modified nickel foam, prepared at room temperature via simple soaking processes, could effectively catalyze the dehydrogenation oxidation of primary amines to generate aromatic and aliphatic nitriles with good yields. Further expanding the application of the easily available electrode, the Ni Co LDH electrode could function as the electron reservoir to realize the decoupled water electrolysis with 100% coulombic efficiency in the membrane-free electrolytic cell. [Display omitted] • Co Ni LDH grown on nickel foam was facilely synthesized via simple soaking processes. • Co Ni LDH boosted primary amine electrooxidation coupled with hydrogen production. • Aromatic and aliphatic nitriles were generated over Ni Co LDH anode with good yields. • Decoupled water electrolysis was achieved relying on Ni Co LDH as electron reservoir. • Hydrogen production in the membrane-free cell reduced electrolytic equipment costs. [ABSTRACT FROM AUTHOR]

Graphene quantum dot (GQD) has been attractive in analytical science field due to its low toxicity, stable photoluminescence. Herein, nitrogen-doped GQD (N-GQD) was prepared by a facile solvothermal treatment of GO using dimethylformamide, and exhibited a green emission with 23.1% quantum yield. The N-GQD probe showed a selective and sensitive fluorescence enhancement response to Al 3+ , the mechanism might be the formation of a complex between Al 3+ and N-GQD constrained the photo-induced electron transfer (PET) process of N-GQD itself. With Benesi-Hildebrand equation, the binding constant and molar ratio between N-GQD and Al 3+ was calculated to be 4.6 × 10 4 L mol −1 and 1:1 respectively. The p K a value of N-GQD was also determined to be 4.4 by capillary electrophoresis. In pH 4.0 PBS solution, there was a good linear relation between the fluorescence intensity and the logarithm of concentration of Al 3+ in the range of 2.5–75 μmol L −1 , the limit of detection (3σ) was 1.3 μmol L −1 . This “Off - On” fluorescence method had been applied to accurate quantification of aluminum in hydrotalcite tablets. What's more, the fluorescence switch property of N-GQD was explored by alternate addition of Al 3+ and EDTA. The probe was also utilized for detection Al 3+ in living cells due to its excellent biocompatibility. [ABSTRACT FROM AUTHOR]

In this paper, visual detection of trace lead ion was established by aptamer and silver staining. The basic strategy was that aminated PS2.M aptamer was immobilized onto slide and formed stable G-quadruplex structure. PbS was generated by adding S 2− , and it catalyzed subsequent silver staining reaction, through the silver staining amplification effect, the slide presented visible ash black. The gray value of slide after silver staining was analyzed and the semi-quantitative detection of Pb 2+ in solution was realized. The results showed that optical darkness ratio (ODR) and logarithmic value of Pb 2+ concentration had a good linear relationship (R 2  = 0.951) over the range of 0.5–10 μM. In addition, there was no obvious interference of other common metal ions for the detection, indicating that this method presented outstanding selectivity. And it was also used for qualitative and semi-quantitative determination of Pb 2+ in soil sample successfully. [ABSTRACT FROM AUTHOR]

There are considerable evidence of reproductive impairment in male organisms with Wilson disease (WD). The purpose of this study was to observe spermatogenesis, mitochondrial damage, apoptosis, and the level of oxidative stress in the testes of Wilson disease model TX mice, and to observe the effect and mechanism of glutathione on testicular spermatogenesis. Mice were divided into a normal control group (control group), Wilson disease model TX mice group (WD group), penicillamine-treated TX mice group (penicillamine group) and glutathione-treated TX mice group (glutathione group). Testicular coefficient, histomorphology of testis and epididymis, number of spermatozoa, apoptosis of spermatogenic cells and expression of apoptosis-related proteins were observed. Ultrastructural analysis of mitochondria and mitochondrial membrane potential (MMP) monitored using JC-1 dye were used to detect mitochondrial damage. The levels of malondialdehyde (MDA), glutathione (GSH), catalase (CAT), and reactive oxygen species (ROS) in testicular cells were measured to assess oxidative stress. Testicular coefficient did not change in mice with Wilson disease. However, the tissue structure of the testicular seminiferous tubules was damaged, and the number of spermatozoa in the epididymal lumen was significantly reduced in WD group. The apoptosis rate in the testes was significantly increased. The protein expression of the pro-apoptotic proteins Bax and Caspase-3 significantly increased, and the expressions of the anti-apoptotic protein Bcl-2 significantly decreased. The levels of ROS and MDA significantly increased, and the levels of CAT and GSH significantly decreased. Mitochondria with abnormal ultrastructure and the rate of JC-1 positive cells were significantly increased in the WD group. After copper chelation by penicillamine, the structure of the testicular seminiferous tubules and the number of spermatozoa in the epididymal lumen were significantly improved. The number of apoptotic cells was significantly reduced. The levels of Bax and Caspase-3 decreased, and the expression of Bcl-2 increased. The contents of CAT and GSH increased, and the levels of ROS and MDA decreased significantly. The abnormal mitochondria and JC-1 positive cells was significantly decreased. The histomorphology of seminiferous tubules, spermatogenic function, apoptosis rate, apoptosis-related proteins, mitochondrial damage, and oxidative stress in Wilson disease TX mice significantly improved after glutathione treatment. Copper deposition in Wilson disease can lead to oxidative stress injury, mitochondrial damage, and apoptosis in the testis, leading to the impairment of spermatogenesis. Glutathione may improve testicular spermatogenesis in male Wilson disease TX mice by inhibiting copper deposition-induced oxidative stress, mitochondrial damage, and apoptosis. [Display omitted] • Copper deposition caused impaired spermatogenesis in mice with Wilson disease (WD). • 2、Copper deposition caused oxidative stress, mitochondrial damage, and apoptosis in WD. • 3、Glutathione improved spermatogenesis in testis of mice with WD. • 4、Glutathione inhibited oxidative stress, mitochondrial damage, and apoptosis. [ABSTRACT FROM AUTHOR]

• P,Cu-codoped cobalt selenide nanoarrays were synthesized via hydrothermal method. • The Cu and P elements are simultaneously doped into the hierarchical nanoarrays. • The as-prepared catalysts showed enhanced activity for overall water splitting. • The co-doped P plays a key factor for boosting the electrocatalyst activity. Highly efficient electrocatalysts with low cost for electrochemical water splitting is important for the intermediate energy conversion. In the present work, P and Cu dual-doped cobalt selenide nanoarrays with hierarchical structure were fabricated via a facile hydrothermal method, involving in-situ growth on a self-supported conductive Ni foam substrate (P,Cu-Co 0.85 Se/NF). The overall water splitting (OWS) performance of the catalysts was systematically studied in alkaline solution. Compared to single-ion-doped or pure Co 0.85 Se, dual incorporation of the anion and cation can contort the lattice and induce powerful electronic interactions, thereby exposing abundant catalytic sites and optimizing the adsorption energy of the reaction intermediates. Benefiting from the merits of P, the Cu-co-doped Co 0.85 Se/NF electrode exhibited outstanding catalytic activity towards hydrogen evolution reaction (HER), generating a 10 mA cm−2 current density at the overpotential of 96.8 mV in 1 M KOH, and the overpotential is 300 mV towards oxygen evolution reaction (OER) with the current density of 100 mA cm−2. Furthermore, when applied it to fabricate OWS cell, the cell voltage is as low as 1.57 V at the current density of 10 mA cm−2. This present work broaden the potential application of the electrocatalytic performance of transition metal dichalcogenides. [ABSTRACT FROM AUTHOR]