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Lactate is the precursor for polylactide. In this study, a lactate producer of Z. mobilis was constructed by replacing ZMO0038 with LmldhA gene driven by a strong promoter PadhB, replacing ZMO1650 with native pdc gene driven by Ptet, and replacing native pdc with another copy of LmldhA driven by PadhB to divert carbon from ethanol to D-lactate. The resultant strain ZML-pdc-ldh produced 13.8 ± 0.2 g/L lactate and 16.9 ± 0.3 g/L ethanol using 48 g/L glucose. Lactate production of ZML-pdc-ldh was further investigated after fermentation optimization in pH-controlled fermenters. ZML-pdc-ldh produced 24.2 ± 0.6 g/L lactate and 12.9 ± 0.8 g/L ethanol as well as 36.2 ± 1.0 g/L lactate and 40.3 ± 0.3 g/L ethanol, resulting in total carbon conversion rate of 98.3% ± 2.5% and 96.2% ± 0.1% with final product productivity of 1.9 ± 0.0 g/L/h and 2.2 ± 0.0 g/L/h in RMG5 and RMG12, respectively. Moreover, ZML-pdc-ldh produced 32.9 ± 0.1 g/L D-lactate and 27.7 ± 0.2 g/L ethanol as well as 42.8 ± 0.0 g/L D-lactate and 53.1 ± 0.7 g/L ethanol with 97.1% ± 0.0% and 99.1% ± 0.8% carbon conversion rate using 20% molasses or corncob residue hydrolysate, respectively. Our study thus demonstrated that it is effective for lactate production by fermentation condition optimization and metabolic engineering to strengthen heterologous ldh expression while reducing the native ethanol production pathway. The capability of recombinant lactate-producer of Z. mobilis for efficient waste feedstock conversion makes it a promising biorefinery platform for carbon-neutral biochemical production.

Biorefinery to produce value-added biochemicals offers a promising alternative to meet our sustainable energy and environmental goals. Acetoin is widely used in the food and cosmetic industries as taste and fragrance enhancer. The generally regarded as safe (GRAS) bacterium Zymomonas mobilis produces acetoin as an extracellular product under aerobic conditions. In this study, metabolic engineering strategies were applied including redistributing the carbon flux to acetoin and manipulating the NADH levels. To improve the acetoin level, a heterologous acetoin pathway was first introduced into Z. mobilis, which contained genes encoding acetolactate synthase (Als) and acetolactate decarboxylase (AldC) driven by a strong native promoter Pgap. Then a gene encoding water-forming NADH oxidase (NoxE) was introduced for NADH cofactor balance. The recombinant Z. mobilis strain containing both an artificial acetoin operon and the noxE greatly enhanced acetoin production with maximum titer reaching 8.8 g/L and the productivity of 0.34 g∙L−1∙h−1. In addition, the strategies to delete ndh gene for redox balance by native I-F CRISPR-Cas system and to redirect carbon from ethanol production to acetoin biosynthesis through a dcas12a-based CRISPRi system targeting pdc gene laid a foundation to help construct an acetoin producer in the future. This study thus provides an informative strategy and method to harness the NADH levels for biorefinery and synthetic biology studies in Z. mobilis.

Schematic illustration of the mechanism of the fast and stable zinc ion storage. The Fe doping introduces interstices that facilitate electrolyte permeation and increase the contact area between the active material and the electrolyte, promoting the kinetics of Zn2+.

Electrocatalysts for hydrogen evolution made from earth’s rich elements are key to a sustainable and clean hydrogen economy. Now, using a straightforward way to make valid catalysts with preferable catalytic activity from inexpensive raw materials in large scale remains challenge. The preparation of nickel-sulfur hybrid nanoplate electrocatalyst has a deep consideration because of its ordinary preparation process, outstanding property, and fine stabilization. In this work, employing an improved chemical vapor deposition (CVD) synthesis method to fabricate a highly efficient and stable NiS2/NiS electrocatalyst prepared by changing the mass of nickel-sulfur ratios of 8:1 (NiS2/NiS-8), 4:1 (NiS2/NiS-4), 2:1 (NiS2/NiS-2), and 1:1 (NiS2/NiS-1), applied to hydrogen evolution reactions (HER). The acquired NiS2/NiS-4 showed excellent HER performance with an overpotential of 202 mV to drive 100 mA/cm2 in 1 M KOH solution with a Tafel slope of 69.0 mV/dec, also with 30 h stability testing. This vigorous catalyst, fabricated from commercial Ni foam, has a potential for industrialization of hydrogen economy and will stimulate the industrial development of nonprecious metal catalyst.

This research specifically reveals the predictability for the volatility on energy futures markets when involving investor sentiment, using the newly launched China’s INE crude oil futures as an incremental evidence. First, we propose a novel investor sentiment index captures the feature of instant sentiment conversion and the internet attention for energy futures markets. Second, we present the nexus between the proposed novel investor sentiment and conditional volatility, which shows that the proposed investor sentiment significantly impacts on return and volatility. It indicates that the emerging markets filled with noise traders like China are more deeply influenced by investor sentiment and bring about more volatility. Third, the results of dual leverage effects in modeling energy futures volatility shows that the optimistic (pessimistic) sentiment shift has negative(positive) effects on volatility, and downward (upward) shocks from bad news (good news) are followed by greater volatility. Fourth, incorporating the novel investor sentiment into models can significantly improve volatility forecasting accuracy because of its smaller loss function results compared with the benchmark models without sentiment. Moreover, high frequency realized volatility and range-based volatility are regarded as real volatility to examine the predictability, and Diebold Mariano test is used to present the difference of forecasting ability. Our results are robust by using the data from China’s Thermal Coal Futures. Overall, we present that the novel investor sentiment can be utilized for monitoring and predicting volatility shocks for emerging markets with lots of noise traders.

The emergence of alternative sustainable energy technologies has stimulated the utilisation of high-efficiency, cost-effective electrodes for renewable energy conversion. The oxygen evolution reaction (OER) is critical for water splitting and rechargeable metal-air batteries. However, the identification of efficient and robust non-noble-metal-based OER electrocatalysts remains a major hurdle for large-scale hydrogen production. Herein, NiVP@NiFeV-LDH heterojunction catalysts were constructed by phosphidation and hydrothermal processing, because OER activity can be improved by coupling NiVP and NiFeV-LDH. NiVP@NiFeV-LDH/NF exhibited remarkable OER performance with an ultralow overpotential of 317 mV at a current density of 100 mA cm−2 and a Tafel slope of 83.0 mV dec−1 in an alkaline environment. The high efficiency of NiVP@NiFeV-LDH/NF is attributed to increased mass and electron transport because of array structure formation and interfacial electronic structure optimisation, respectively. This work provides a novel approach for augmenting the OER performance of non-noble-metal-based electrocatalysts for energy conversion applications.

Background Extensive muscle atrophy is a common occurrence in orthopaedics patients who are bedridden or immobilized. The incidence is higher in intensive care unit (ICU) inpatients. There is still controversy about how to use neuromuscular electrical stimulation (NMES) in ICU patients. We aim to compare the effectiveness and safety of NMES to prevent muscle atrophy in intensive care unit (ICU) patients without nerve injury. Methods ICU patients without central and peripheral nerve injury were randomized into experimental group I (Exp I: active and passive activity training (APAT) + NMES treatment on the gastrocnemius and tibialis anterior muscle), experimental group II (Exp II: APAT + NMES treatment on gastrocnemius alone), and control group (Ctl: APAT alone). Changes in the strength of gastrocnemius, the ankle range of motion, and the muscle cross-section area of the lower leg were evaluated before and after the intervention. Also, changes in prothrombin time, lactic acid, and C-reactive protein were monitored during the treatment. Results The gastrocnemius muscle strength, ankle joint range of motion, and cross-sectional muscle area of the lower leg in the three groups showed a downward trend, indicating that the overall trend of muscle atrophy in ICU patients was irreversible. The decrease in gastrocnemius muscle strength in Exp I and Exp II was smaller than that in the control group (P P P P > 0.05). Conclusion In addition to early exercise training, NMES should be applied to prevent muscle atrophy for patients without nerve injury in ICU. Also, simultaneous NMES treatment on agonist/antagonist muscle can enhance the effect of preventing muscle atrophy. Trial registration This study was prospectively registered in China Clinical Trial Registry (www.chictr.org.cn) on 16/05/2020 as ChiCTR2000032950.

A new class of near-infrared (NIR) reflectance pigments based on Co1−xMgxCr2−yAlyO4 (x = 0–1 and y = 0–2) was synthesised using the Pechini-type sol-gel process. The developed powders were characterised by thermogravimetry and differential scanning calorimetry, X-ray diffraction (XRD), ultraviolet–visible near-infrared diffuse reflectance spectroscopy, and colour Commission Internationale del'Eclairage (CIE) 1976 (L*a*b*) colour scales. The XRD patterns revealed characteristic peaks of the spinel structure with good crystallinity. Substituting Mg2+ for Co2+ ions in the tetrahedral positions and Al3+ for Cr3+ ions in the octahedral positions of CoCr2O4 reduces the cost and changes the colour of the pigment (green to yellow and then blue). Moreover, the synthesised pigments exhibited high NIR solar reflectance in the 780–2,500 nm wavelength range. The thermal and chemical stability of the pigments was also studied. Our findings demonstrate the potential for applying these pigments in cool colourants.

In this paper, a method of power system equipment recognition based on image processing is proposed. Firstly, we carry out wavelet transform on the sound signal of power system equipment collected from the site, and obtain the wavelet coefficient–time diagram. Then, the similarity of wavelet coefficients–time images of different equipment and the same equipment in different periods is calculated, which is used as the basis of the feasibility of image recognition. Finally, we select the HOG features of the image, and classify the selected features using SVM classifier. The method proposed in this paper can accurately identify and classify power system equipment through sound signals, and is different from the traditional method of classifying sound signals directly. The advantages of image processing can be effectively utilized through image processing to avoid the limitations of sound signal processing.

Amyotrophic lateral sclerosis (ALS) is a rapidly progressive and highly fatal neurodegenerative disease. Although the pathogenesis of ALS remains unclear, increasing evidence suggests that a key contributing factor is mitochondrial dysfunction. Mitochondria are organelles in eukaryotic cells responsible for bioenergy production, cellular metabolism, signal transduction, calcium homeostasis, and immune responses and the stability of their function plays a crucial role in neurons. A single disorder or defect in mitochondrial function can lead to pathological changes in cells, such as an impaired calcium buffer period, excessive generation of free radicals, increased mitochondrial membrane permeability, and oxidative stress (OS). Recent research has also shown that these mitochondrial dysfunctions are also associated with pathological changes in ALS and are believed to be commonly involved in the pathogenesis of the disease. This article reviews the latest research on mitochondrial dysfunction and its impact on the progression of ALS, with specific attention to the potential of novel therapeutic strategies targeting mitochondrial dysfunction.

The oxygen evolution reaction (OER) involves four electron transfer processes and is of great significance in water electrolysis. The development of efficient and robust non-precious OER electrocatalysts remains a critical challenge for the production, storage and conversion of renewable energy. Herein, vertically NiCo2O4 nanosheets are grown on Ti mesh via a facile solvothermal method which is followed by low-temperature calcination. The NiCo2O4/Ti catalyst exhibits outstanding OER performance with a low overpotential of 353 mV to drive the current density of 10 mA cm−2 and a Tafel slope of 61 mV dec−1 in alkaline solution. Moreover, the stable electrocatalyst undergoes negligible degradation in alkaline media at least 20 h. The acceleration of the electrochemical OER likely stems from the facile electron transfer promoted by the NiCo2O4/Ti interface as revealed by X-ray photoelectron spectroscopy. This work introduces a novel strategy for the establishment low-cost electrocatalysts for electrochemical water splitting.

Ammonium vanadate (NH4V3O8) materials have attracted considerable attention due to their low cost, high discharge capacity, and simple synthesis process. However, the further application of NH4V3O8 materials as cathode for lithium-ion batteries is hindered by the low electronic conductivity and lithium-ion diffusion coefficient. Herein, intersperse Super P nanoparticles between NH4V3O8 microsheets to increase the Li+ diffusion coefficient of NH4V3O8 electrodes. Compared with pure NH4V3O8, the cycling stability of NH4V3O8/Super P composites improved obviously. At a current density of 15 mA g−1 after 200 cycles, the reversible capacity of composites (110 mAh g−1) is much higher than the pure NH4V3O8 (70 mAh g−1). Besides, the composites exhibit excellent rate capability, and the reversible capacity achieves 66 mAh g−1 at a high current density of 300 mA g−1. The excellent electrochemical performance is mainly attributed to the addition of Super P carbon black nanoparticles, which increases the conductivity and the Li+ diffusion coefficient.

Heterostructure construction and heteroatom doping are powerful strategies for enhancing the electrolytic efficiency of electrocatalysts for overall water splitting. Herein, we present a P-doped MoS2/Ni3S2 electrocatalyst on nickel foam (NF) prepared using a one-step hydrothermal method. The optimized P[0.9mM]-MoS2/Ni3S2@NF exhibits a cluster nanoflower-like morphology, which promotes the synergistic electrocatalytic effect of the heterostructures with abundant active centers, resulting in high catalytic activity for the hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) in alkaline electrolyte. The electrode exhibits low overpotentials and Tafel slopes for the HER and OER. In addition, the catalyst electrode used in a two-electrode system for overall water splitting requires an ultralow voltage of 1.42 V at 10 mA·cm−2 and shows no obvious increase in current within 35 h, indicating excellent stability. Therefore, the combination of P doping and the heterostructure suggests a novel path to formulate high-performance electrocatalysts for overall water splitting.

Low cost electrodes with high activity and stability are the key to water splitting for green hydrogen production. Herein, an efficient integrated Ni/CoFe LDH array electrocatalyst is synthesized by a one-step electrodeposition strategy. The Ni/CoFe LDH shows splendid electrocatalytic performance for water oxidation, with a low overpotential (324 mV at a 50 mA cm−2 current output), a small Tafel slope (32 mV dec−1), and excellent durability. The improved activity can be attributed to the synergy of the electronic structure fine-tuning and the hydrophilic nanostructured surface.

The Stern-Gerlach (SG) effect is well known as the spin-dependent splitting of a beam of atoms carrying magnetic moments by a magnetic-field gradient, leading to the concept of electron spin. Antiferromagnets can accommodate two magnon modes with opposite spin polarizations, which is equivalent to the spin property of electrons. Here, we propose the existence of an all-magnonic SG effect in antiferromagnetic magnonic system, where a linearly polarized spin-wave beam is deflected by a straight Dzyaloshinskii-Moriya interaction (DMI) interface into two opposite polarized spin-wave beams propagating in two discrete directions. Moreover, we observe bi-focusing of antiferromagnetic spin waves induced by a curved DMI interface, which can also spatially separate thermal magnons with opposite polarizations. Our findings provide a unique perspective to understand the rich phenomena associated with antiferromagnetic magnon spin and would be helpful for polarization-dependent application of antiferromagnetic spintronic devices., 5 pages, 4 figures

A hybrid heterostructure eletrocatalyst supported on Ni foam is facilely synthesized as a high-performance OER electrocatalyst for alkaline water electrolysis. Compared to their pristine NiV-LDH counterpart, the self-made NiV-LDH@FeOOH heterostructures exhibit an extremely low overpotential of ∼297 mV at 100 mA cm-2 current output, and excellent long-term durability.

Recent research on organic semiconductors has revealed that the composition of the constituent organic material, as well as the subtle changes in its structure (the stacking order of molecules), can noticeably affect its bulk properties. One of the reasons for this is that the charge transport in conjugated materials is strongly affected by their structure. Further, the charge mobility increases significantly when the conjugated materials exhibit self-assembly, resulting in the formation of ordered structures. However, well-organized nanostructures are difficult to obtain using classical solution processing methods, owing to their disordered state. A simple strategy for obtaining well-ordered material films involves synthesizing new conjugated materials that can self-organize. Introducing hydrogen bonding in the materials to yield hydrogen-bonded material superstructures can be a suitable method to fulfill these critical requirements. The formed hydrogen bonds will facilitate the assembly of the molecules into a highly ordered structure and bridge the distance between the adjacent molecules, thus enhancing the intermolecular charge transfer. In this minireview, hydrogen-bonded small molecules and polymers as well as the relationship between their chemical structures and performances in organic field-effect transistors are discussed.

Long non-coding RNAs (lncRNAs) have been identified as a class of regulatory RNAs that participate in both physiological and pathological conditions, including acute kidney injury. However, the roles of lncRNA dysregulation in the pathogenesis of contrast-induced acute kidney injury (CI-AKI) are largely unknown. In the present study, the expression profiles of lncRNAs in kidney tissue were compared between rats with CI-AKI and controls using high-throughput RNA sequencing. In total, 910 differentially expressed (DE) lncRNAs (DElncRNAs), including 415 downregulated and 495 upregulated lncRNAs, were identified at 12 h after intra-arterial iodinated contrast medium injection (fold change ≥2; P

Since more and more investors are affected by the Internet finance, this paper focuses on examining whether the systematic trading among investors would lead to stock return comovements beyond the usual risk factors. Internet finance investor sentiment index (IFIS) measures the sentiment related to Internet finance investors' behaviors, which is found to be a systematic factor of stock market returns. To clarify the influence mechanism of IFIS, two groups of portfolios are constructed. First, stocks are sorted into three portfolios according to their degrees of relevance to Internet financial products. IFIS has more significant impact on stocks of firms closely linked to Internet financial products. Second, the role of IFIS on return comovements is further examined using size portfolios. Interestingly, IFIS has significant incremental explanatory power, beyond Fama and French (2015) five factors, on return comovements for stocks with larger market capitalization. This phenomenon is contradictory to the findings by using existing stock investor sentiment in the literature. Our findings have strong implications for research on Internet finance and stock return comovements.

Three π-conjugated large organic molecules based on diketopyrrolopyrrole (DPP), benzodipyrrolidone (BDP) and naphthodipyrrolidone (NDP) are synthesized and characterized. By introducing bi-thiophene units at the end of DPP/BDP/NDP chromophores, the molecules are able to form a donor–acceptor–donor (D-A-D) system. All of them exhibit high thermal stability, strong aggregation, high values in highest occupied and low values in lowest unoccupied molecular orbital (HOMO/LUMO) energy levels. In this work, a simple solution process technique for large organic molecules crystal organic field-effect transistors (OFETs) is used to fabricate devices. DPP- and BDP-based large organic molecular crystals exhibit p-type behavior with hole mobility of 0.02 cm2 V−1 s−1 and 0.09 cm2 V−1 s−1, while large organic molecular crystal based on NDP shows n-type behavior with electron mobility up to 0.26 cm2 V−1 s−1. This work demonstrated that extension of the π-conjugation system is a useful strategy to build high charge mobility materials. In addition, BDP is an interesting electron-withdrawing block for p-type semiconductor while NDP is a promising chromophore for the construction of n-type high-performance OFETs.

Electrode materials are the key to the electrochemical performance of supercapacitors. This study reports the electrochemical properties of V2O5 supercapacitors. V2O5 nanosheets with different morphologies were prepared by controlling the solvent under a facile hydrothermal method. The phase and the morphology of the samples were characterized by x-ray diffraction and scanning electron microscopy. The electrochemical properties of V2O5 nanosheets with different morphologies were studied by cyclic voltammetry, galvanostatic charge–discharge, and electrochemical impedance spectroscopy. The charge transfers resistance decreases from 3.2 Ω of V2O5 particles to 2.0 Ω of V2O5 nanosheets. V2O5 nanosheets exhibit higher specific capacity (375 F g−1) than V2O5 particles (318 F g−1) in K2SO4 solution. The cycling capacity retention keeps 96.8% for 1000 cycles at 0.5 A g−1 in K2SO4 solution, indicating better cycling stability.

Ag-doped ZnO nanorods growth on a PET-graphene substrate (Ag-ZnO/PET-GR) with different Ag-doped content were synthesized by low-temperature ion-sputtering-assisted hydrothermal synthesis method. The phase composition, morphologies of ZnO, and electrical properties were analyzed. Ag-doping affects the initially perpendicular growth of ZnO nanorods, resulting in oblique growth of ZnO nanorods becoming more obvious as the Ag-doped content increases, and the diameter of the nanorods decreasing gradually. The width of the forbidden band gap of the ZnO films decreases with increasing Ag-doped content. For the Ag-ZnO/PET-GR composite structure, the Ag-ZnO thin film with 5% Ag-doped content has the largest carrier concentration (8.1 × 1018 cm−3), the highest mobility (67 cm2 · V−1 · s−1), a small resistivity (0.09 Ω·cm), and impressive electrical properties.

The water oxidation reaction plays a major role in many alternative-energy systems because it provides the electrons and protons required for the use of renewable electricity. We report the tuning of the iron molybdate (FeMoO4) electron structure via a coupled interface between the catalytic centers and the substrate. Our developed FeMoO4 catalysts can provide a 50 mA cm-2 current density at 1.506 V vs. RHE with excellent stability in 1.0 M KOH. The improved performance can be ascribed to the synergy of the optimized electronic structures and hierarchical nanostructure.

The application of polydopamine (PDA)-modified titanium dioxide nanoparticles (nano-TiO

We theoretically study the effect of Dzyaloshinskii-Moriya interaction (DMI) on the focusing of a spin-wave lens that is constructed by a circular interface between two magnetic films. We analytically derive the generalized Snell's law in the curved geometry and the position of the focal point which exhibits a peculiar off-axial focusing behavior. We uncover a strong dependence of the focal point on both the material parameters and the frequency of incident spin waves. Full micromagnetic simulations compare well with theoretical predictions. Our findings would be helpful to manipulate spin waves in chiral magnets and to design functional magnonic devices., Comment: 5 pages, 5 figures

The application of polydopamine (PDA)-modified titanium dioxide nanoparticles (nano-TiO2@PDA) as a new blue-light-activated tooth whitening material was discussed for the first time. Compared with the classical clinical whitening agent (peroxide, hydrogen peroxide, and carbamide peroxide), nano-TiO2@PDA-based treatment not only had a similar whitening effect but also showed remarkably less damage on the enamel structure. Essentially, a highly effective and nondestructive tooth whitening treatment could thus be realized accordingly. The toxicity and antibacterial properties of this material were also evaluated systematically.

A novel donor-acceptor type aminobenzodifuranone based chromophore molecule, coded as ABDF, with a benzodifuranone (BDF) core as acceptor and an N-ethylamino side chain as donor moiety was synthesized and used in single crystal organic field-effect transistors (OFETs). The optical, thermal, electrochemical properties of ABDF were also investigated. Compared to other BDF or halogenated BDF analogs, the solution absorption of ABDF exhibits large bathochromic shift over 100 nm, indicating the strong intramolecular charge transfer intensity within the molecules. In particular, the incorporation of amino groups into the BDF core also enables the formation of intermolecular hydrogen-bonding interactions in the solid states of ABDF as proved by the FT-IR results. The crystalline ABDF based OFET devices was simply prepared by drop-casting the ABDF solution on to the electrode-prepatterned substrates, giving a hole mobility as high as 0.42 cm2/V·s without large degradation after store in ambient environment for up to two months. ABDF is a promising chromophore for high performance organic field-effect transistors.

In space-time adaptive processing (STAP), the selected training samples should have the same covariance matrix as the clutter of the cell under test (CUT). The traditional methods usually select samples whose waveforms are similar to that of the CUT. We notice that completely dissimilar waveforms may have the same covariance matrix. As a result, many valid samples are lost in traditional methods. So we propose a training samples selection method based on system identification. The proposed methods select samples with similar covariance matrices instead of similar waveforms. First, a samples selection model based on system identification is proposed. Then, the neural network is used to identify the clutter model of the CUT. Finally, samples are selected according to the output variance. Compared with the methods in [1, 2, 3, 4], the proposed method has the following advantages: (1) More than twice the valid training samples can be obtained; (2) The clutter suppression performance can be improved more than 2 dB for the measured data.

The exploration of high-performance, inexpensive noble-metal-free electrocatalysts for the oxygen evolution reaction (OER) may be critical for sustainable mass production of renewable energy. In this study, vanadium-doped Ni3S2 nanorod arrays grown on three-dimensional nickel foam (V-Ni3S2/NF) were designed and synthesized by a facile hydrothermal route. Electrochemical measurements showed that the sample with an appropriate amount of V doping (S: V mass ratio of 25:3) exhibited superior OER performance, with an overpotential of 189 mV at a current density of 100 mA cm−2 and a low Tafel slope of 148.87 mV dec−1. The improved catalytic performance can be attributed to the optimization of the electronic structure resulting from enhanced electron transfer due to doping with impurity atoms. Detailed characterization showed that homogeneous V doping changed the morphology of Ni3S2 from nanosheets to nanorods; it also introduced additional catalytic active sites and significantly improved the electrocatalytic activity for the OER. In addition, V-Ni3S2/NF exhibited excellent electrocatalytic stability compared to noble-metal (IrO2) electrocatalysts. The introduction of vanadium suggests a new approach to the design of high-performance OER catalysts in alkaline medium.

Electrochemical oxidation of biomass convert into worthy production is considered to be a prospective alternative to slow kinetic oxygen evolution reaction (OER) in order to facilitate H2 generation. Herein, Mo-doped Ni0.85Se on the Ni foam (denoted as NF@Mo-Ni0.85Se) was prepared as effective bifunctional catalyst to boost H2 production and translate 5-hydroxymethylfurfural (HMF) into 2, 5-furfuran carboxylic acid (FDCA) simultaneously. Operando electrochemical impedance spectroscopy (EIS) and theoretical calculations confirm that the Mo doping could speed the electron transmission within the catalyst and downshift the d-band center of Ni in NF@Ni0.85Se, which is not only conducive to abating H* adsorption energy, but further promotes the hydrogen evolution reaction (HER) and organic hydrogen adsorption process. The as-synthesized electrocatalysts have shown outstanding hydrogen evolution property in acid, neutral, alkaline and seawater. When the NF@Mo-Ni0.85Se||NF@Mo-Ni0.85Se catalyst couple was employed for HER as well as HMF oxidation in basic electrolytes, the potential only required a potential of 1.50 V to obtain the current density of 50 mA cm−2, lower than that of overall water splitting (1.68 V). This present work especially emphasizes the significance of doping transition metals to improve material properties for constructing bifunctional electrocatalysts towards highly efficient energy utilization.

Hollow core@shell TiO2@CdS composite was synthesized via facile and controlled homogeneous precipitation method, the as-prepared samples were characterized by XRD, SEM, TEM, FTIR, EDS UV–vis adsorption, and BJH. The results of the photocatalytic experiment demonstrated the TiO2/CdS hybrid with Ti/Cd molar ratio of 1:2 (denoted as T/2C) possesses the highest photocatalytic activity, the degradation rate of T/2C towards methyl orange (MO) is 78% and 80% under simulated UV light and sun light, respectively. Additionally, T/2C also presents photocatalytic performance on H2 production (114.375 µmol/h g). Based on the experiment results, a probable charger transfer mechanism of T/2C was proposed. In view of the unique hollow structure and high photocatalytic characteristics, it is looking forward to exhibit great potential for applications in wastewater treatment and H2 evolution.

Background Efficient and convenient genome-editing toolkits can expedite genomic research and strain improvement for desirable phenotypes. Zymomonas mobilis is a highly efficient ethanol-producing bacterium with a small genome size and desirable industrial characteristics, which makes it a promising chassis for biorefinery and synthetic biology studies. While classical techniques for genetic manipulation are available for Z. mobilis, efficient genetic engineering toolkits enabling rapidly systematic and high-throughput genome editing in Z. mobilis are still lacking. Results Using Cas12a (Cpf1) from Francisella novicida, a recombinant strain with inducible cas12a expression for genome editing was constructed in Z. mobilis ZM4, which can be used to mediate RNA-guided DNA cleavage at targeted genomic loci. gRNAs were then designed targeting the replicons of native plasmids of ZM4 with about 100% curing efficiency for three native plasmids. In addition, CRISPR–Cas12a recombineering was used to promote gene deletion and insertion in one step efficiently and precisely with efficiency up to 90%. Combined with single-stranded DNA (ssDNA), CRISPR–Cas12a system was also applied to introduce minor nucleotide modification precisely into the genome with high fidelity. Furthermore, the CRISPR–Cas12a system was employed to introduce a heterologous lactate dehydrogenase into Z. mobilis with a recombinant lactate-producing strain constructed. Conclusions This study applied CRISPR–Cas12a in Z. mobilis and established a genome editing tool for efficient and convenient genome engineering in Z. mobilis including plasmid curing, gene deletion and insertion, as well as nucleotide substitution, which can also be employed for metabolic engineering to help divert the carbon flux from ethanol production to other products such as lactate demonstrated in this work. The CRISPR–Cas12a system established in this study thus provides a versatile and powerful genome-editing tool in Z. mobilis for functional genomic research, strain improvement, as well as synthetic microbial chassis development for economic biochemical production.

The pathogenesis of contrast-induced acute kidney injury (CI-AKI) is incompletely understood. MicroRNAs (miRNAs) are important mediators that normally function via post-transcriptional degradation of target mRNAs. Emerging evidence indicates the appearance of differentially expressed (DE) miRNAs in CI-AKI following the injection of intravenous contrast medium. However, there are differences in the pathological mechanism and incidence of CI-AKI between intravenous and intra-arterial contrast administration. The present study aimed to investigate the critical roles of dysregulated miRNAs and their associated mRNAs in kidney injury following intra-arterial contrast medium exposure. Based on a reliable CI-AKI rat model, we conducted genome-wide miRNA and mRNA expression profiling analysis using deep sequencing. In the study, 36 DE mature miRNAs were identified (fold change > 1.5 and p value < 0.05) in the kidneys of CI-AKI rats (n = 3) compared with that in the controls (n = 3), consisting of 23 up-regulated and 13 down-regulated DE miRNAs. Bioinformatic analysis revealed that wingnut (Wnt), transforming growth factor beta (TGF-β), and 5'-AMP-activated protein kinase (AMPK) signaling pathways were most likely to be modulated by these dysregulated miRNAs. Around 453 dysregulated genes (fold change > 2.0 and p value < 0.05) were identified. Integrated analysis revealed 2037 putative miRNA-mRNA pairs with negative correlations. Among them, 6 DE miRNAs and 13 genes were selected for further quantitative real-time reverse transcription polymerase chain reaction validation (n = 6 for each group), and a good correspondence between the two techniques was observed. In conclusion, the present study provided evidence of miRNA-mRNA interactions in the development of kidney injury following an intra-arterial contrast injection. These findings provide insights into the underlying mechanisms of CI-AKI.

Nanocoating combine the protective properties of conventional coating system with effects on nanoscale such as high hardness, UV scattering, uniform dispersing, etc. Their facile and low-cost synthesis, together with superior protective properties and multi-functionalities, makes nanocoating attractive candidates for next-generation coating system. In this review, a brief introduction regarding to mainstream nanocoating and its related challenges including the zinc oxide-, titanium dioxide-, silica dioxide-, graphene-, carbon nanotube-based nanocoating system is presented. Finally, a perspective of the nanocoating is demonstrated.

Inspired by cocktails, we designed a medium term (2–20 weeks) male contraceptive strategy. Through a sequential injection process of four reagents (calcium alginate hydrogel, PEG-Au nanoparticles (PEG-AuNps), EDTA, and PEG-AuNps), physical clogging of the vas deferens and chemical inhibition of the sperm motility were realized simultaneously. The contraceptive period could be directly preset by adjusting the injection ratio of each reagent. More interesting, the embolism area could be readily dredged through a short-time noninvasive near-infrared irradiation. The present study offered an effective and reversible manner to fill the gap of current medium-term contraceptive strategy. In addition, the proposed in vivo pipeline plugging technology, with a flexible noninvasive self-cleared characteristic, might also provide a convenient and reliable strategy for some other biomedical engineering researches.

Additional file 1: Figure S1. The transformation efficiency of Z. mobilis ZM4 and the Cas12a expressing strain with or without the expression of crRNA targets. ZM4 represented the wild-type strain Zymomonas mobilis ZM4, ZM4-Cas12a represented the recombinant strain with Cas12a integrated at the ZMO0038 locus of ZM4 genome. pEZ-sgr and its derivates containing crRNA scaffold, the pEZ-Cas12a expressing both the Cas12a effector nuclease and the crRNA via a single plasmid. Values are the means of experiments with three or more technical replicates; error bars are standard deviation.

Most of the online lending rate are predominately determined by the platform, especially in the Chinese online lending markets, which indicates that the online lending rate is “not-fully marketized”. Based on a sample of 20 representative online lending platforms with daily data during June 1, 2017 to May 31, 2018 collected from Net credit eye and Lingyicaijing, our results, first, show that the average duration of loans, pending balance, newly added investors, and relative repayment amount are all significant factors for online lending rates. Second, from the view of the whole industry, the increase of the new investors also attracts more risk-seeking investors enter into the industry, who have considerable influences on online lending rates. Finally, when considering the credit rating of each individual platform, the explanatory power of the above factors is gradually weakened as the platform rating declines. This interesting finding suggests that the online lending rate of any platform can reasonably reflect its risks if the platforms keep better regulatory compliance. Our results provide theoretical and empirical supports for both regulators and investors.

An isolable and ambient stable bay-substituted perylene diimide adical anion salt was straightforwardly synthesized by base catalysis reduction of N,N-diethylhexyl-1,7-di(pentafluoro-phenoxyl) perylene diimide (DFPDI) in polar solvents, such as acetone, DMF, DMSO, NMP in yields of 48.7 %. Elemental analysis and 1H NMR, 13C NMR and EPR were carried out to confirm the formation of the compounds. Solvent-dependent cyclic voltammetries revealed the only condition for generating DFPDI radical anion in polar solvents—the reduction potential (DFPDI/DFPDI−) is more positive than −0.36 V (vs. Ag/AgCl). Redox studies revealed that DFPDI radical anion was not only ambient stable to moderate oxidants air (O2) and moisture for prolonged existence but also sensitive to strong oxidants-acid H+ and strong oxidization metal ions with low limit value.

In this work, a series of near-infrared reflective inorganic pigments with a general formula Co0.5Mg0.5Al2 − xFexO4 (x = 0.0, 0.2, 0.4, 0.6, 0.8, 1.0) were successfully prepared by Pechini-type sol–gel method. Comprehensive analyses were carried out to characterize the developed pigment powders including thermogravimetry and differential scanning calorimetry, X-ray diffraction, field emission scanning electron microscopy, ultraviolet–visible near infrared diffuse reflectance spectroscopy, and CIE-L⁎a⁎b⁎ 1976 color scales. The results demonstrated that the single-phase Co0.5Mg0.5Al2 − xFexO4 was synthesized at an optimum temperature of 900 °C. The resulting calcined powders have a well-developed cubic spinel structure. The substitution of Fe3 + for Al3 + in Co0.5Mg0.5Al2 − xFexO4 changes the color from blue to black and the band gap shifts from 4.40 eV to 3.50 eV. And Fe doped pigments possess high near-infrared solar reflectance (> 43%) in the range of 780–2500 nm. Therefore, these Co0.5Mg0.5Al2 − xFexO4 powders have great potential in serving as cool pigments for building coatings.

This work presents a novel approach to improving the load flexibility of coal-fired power plant by integrating high temperature thermal energy storage (HTTES) through additional thermodynamic cycle. It aims to investigate the feasibility of introducing an HTTES-aided additional cycle into the steam-water cycle of conventional coal-fired power plant and to test how a high round-trip efficiency can be achieved with the HTTES integration. The thermal system and operation mode of an HTTES-aided coal-fired power plant were described. The performance evaluation model was built and its performance was discussed based on a 600 MW subcritical coal-fired power plant model. The results show that the proposed approach is feasible to improve the load flexibility of the conventional coal-fired power plant. An additional net power can be obtained while the original unit works at its rated condition. The initial steam pressure of the additional cycle is the determining factor for the round-trip efficiency and a round-trip efficiency of 44.18% can be obtained. This work is expected to provide a detailed reference on the use of HTTES system to improve the load flexibility of coal-fired power plants and further to relieve the serious problem of the curtailment for fluctuating renewable power generation in China.

Wheat straw (WS), as a cheap and abundant agricultural waste, is usually burned directly in farmland and causes severe air pollution. Therefore, biochar derived from waste WS is prepared and modified by nanoscaled zinc oxide through a facile in-situ surface-modification process. For ease of use, a 3D printed finger-sized unit (FSU) loaded with the above as-prepared WS is designed and implemented. Each unit weighs only 4 g, and could simultaneously reduce three major water contaminants: bacteria, organic dyes, and heavy metal ions. Moreover, it is interesting to note that fresh wheat straw is a flexible material and has excellent electrical conductivity after carbonization. These two properties (flexibility and conductivity) could further adjust water purification performance. The subsequent cellular and animal tests confirmed the biosafety of the water purified with FSU alone.