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The charge density and charge transfer resistance of the assisting catalyst have a significant impact on the hydrogen evolution performance of bimetallic sulfides. However, existing mechanistic discussions often overlook the charge density between the two catalysts and whether the assisting catalyst produces enough photo-generated electrons. Here, we propose a simple method for the synthesis of 2-acetylene-(copper metal-organic frameworks) (ACu-MOFs) to improve the hydrogen evolution performance of bimetallic sulfides. Compared to copper metal-organic frameworks (Cu-MOFs), these ACu-MOFs have higher charge density and lower charge transfer resistance. More importantly, the introduction of alkyne-based Cu-MOFs further promotes the hydrogen evolution performance of bimetallic sulfides under 5 W LED light, and XPS is used to determine the difference in charge density between ACu-MOFs and Cu-MOFs and the improvement in contact electron transfer after bimetallic sulfide modification. This work mainly discusses the charge density, charge transfer resistance, and the number of photo-excited electrons generated, and provides a reasonable explanation.
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Different from developed countries, there is a paucity of research examining how the Dietary Approaches to Stop Hypertension (DASH) and Mediterranean diets relate to lipids in less-developed ethnic minority regions (LEMR). A total of 83 081 participants from seven ethnic groups were retrieved from the baseline data of the China Multi-Ethnic Cohort study, which was conducted in less-developed Southwest China between May 2018 and September 2019. Multivariable linear regression models were then used to examine the associations of the DASH and alternative Mediterranean diet (AMED) scores, assessed by modified DASH score and AMED, as well as their components with total cholesterol (TC), LDL-cholesterol, HDL-cholesterol, TAG and TC/HDL-cholesterol. The DASH scores were negatively associated with TC, HDL-cholesterol and TAG. Comparing the highest quintiles with the lowest DASH scores, TC decreased 0·0708 (95 % CI -0·0923, -0·0493) mmol/l, HDL-cholesterol decreased 0·0380 (95 % CI -0·0462, -0·0299) mmol/l and TAG decreased 0·0668 (95 % CI -0·0994, -0·0341) mmol/l. The AMED scores were negatively associated with TC, LDL-cholesterol and HDL-cholesterol. Comparing the highest quintiles with the lowest AMED scores, TC decreased 0·0816 (95 % CI -0·1035, -0·0597) mmol/l, LDL-cholesterol decreased 0·0297 (95 % CI -0·0477, -0·0118) mmol/l and HDL-cholesterol decreased 0·0275 (95 % CI -0·0358, -0·0192) mmol/l. Although both the DASH diet and the Mediterranean diet were negatively associated with blood lipids, those associations showed different patterns in LEMR, particularly for TAG and HDL-cholesterol.
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Dieta Mediterrânea , Abordagens Dietéticas para Conter a Hipertensão , Humanos , Etnicidade , Estudos de Coortes , Minorias Étnicas e Raciais , Grupos Minoritários , Lipídeos , HDL-Colesterol , LDL-ColesterolRESUMO
By utilizing a target biorecognition reaction to induce the self-assembly of G-quadruplexes and the aggregation of gold nanoparticles (Au NPs), this work develops a novel colorimetric biosensing method for kanamycin (Kana) antibiotic detection. The compact G-quadruplex structure was assembled from its two half-split sequences which were designed in two hairpin substrates of the Mg2+-dependent DNAzyme (MNAzyme). Besides hybridizing with the aptamer strand, the MNAzyme sequence was also split into two half fragments to be designed in the two substrates. Upon the aptamer-recognition reaction toward Kana, the MNAzyme strand could be quantitatively released to cause the exposure of the split G-quadruplex-sequences on two hairpin substrate-modified Au NPs and simultaneous release of two half fragments of the MNAzyme-sequence. Thus, the K+-assisted self-folding of G-quadruplexes causes the cross-linking of the two Au NPs to realize the Au NP aggregation-based colorimetric signal output (measured at the largest absorption peak near 520 nm). Meanwhile, the self-assembled formation of the second MNAzyme drastically amplified the signal response. Under the optimal conditions, a wide linear range from 0.1 pg mL-1 to 10 ng mL-1 and an ultrahigh sensitivity with the detection limit of 76 fg mL-1 were obtained. The dose-recovery experiments in real samples showed satisfactory results with recoveries from 98.4 to 105.4% and relative errors compared with the ELISA method less than 4.1%. Due to the high selectivity, excellent repeatability and stability, and simple manipulation, this method indicates a promising potential for practical applications. A novel homogeneous biosensing method was developed for the convenient detection of the kanamycin antibiotic. The target biorecognition-induced and dual DNAzyme-catalytic assembly of G-quadruplexes enabled the amplified aggregation of gold nanoparticles for the simple, cheap, stable, and ultrasensitive colorimetric signal transduction of the method.
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DNA Catalítico , Quadruplex G , Nanopartículas Metálicas , Antibacterianos , DNA Catalítico/química , Ouro/química , Canamicina , Nanopartículas Metálicas/química , OligonucleotídeosRESUMO
It is quite challenging to prepare subnanometer porous materials from traditional porous precursors, and use of supramolecules as carbon sources was seldom reported due to the complex preparation and purification processes. We explore a facile one-pot method to fabricate supramolecular coordination compounds as carbon sources. The resultant CB[6]-derived carbons (CBC) have a high N content of 7.0-22.0%, surface area of 552-861 m2 g-1, and subnano/mesopores. The CBC electrodes have a narrow size distribution at 5.9 Å, and the supercapacitor exhibits an energy density of 117.1 Wh kg-1 and a potential window of over 3.8 V in a two-electrode system in the ionic liquid (MMIMBF4) electrolyte with appropriate cationic (5.8 Å) and anionic (2.3 Å) diameter. This work presents the facile fabrication of novel supermolecule cucurbituril subnanoporous carbon materials and the smart design of "pores and balls" for high-performance energy storage systems.
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MOTIVATION: The multimodal data fusion analysis becomes another important field for brain disease detection and increasing researches concentrate on using neural network algorithms to solve a range of problems. However, most current neural network optimizing strategies focus on internal nodes or hidden layer numbers, while ignoring the advantages of external optimization. Additionally, in the multimodal data fusion analysis of brain science, the problems of small sample size and high-dimensional data are often encountered due to the difficulty of data collection and the specialization of brain science data, which may result in the lower generalization performance of neural network. RESULTS: We propose a genetically evolved random neural network cluster (GERNNC) model. Specifically, the fusion characteristics are first constructed to be taken as the input and the best type of neural network is selected as the base classifier to form the initial random neural network cluster. Second, the cluster is adaptively genetically evolved. Based on the GERNNC model, we further construct a multi-tasking framework for the classification of patients with brain disease and the extraction of significant characteristics. In a study of genetic data and functional magnetic resonance imaging data from the Alzheimer's Disease Neuroimaging Initiative, the framework exhibits great classification performance and strong morbigenous factor detection ability. This work demonstrates that how to effectively detect pathogenic components of the brain disease on the high-dimensional medical data and small samples. AVAILABILITY AND IMPLEMENTATION: The Matlab code is available at https://github.com/lizi1234560/GERNNC.git.
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Doença de Alzheimer , Disfunção Cognitiva , Doença de Alzheimer/genética , Encéfalo , Disfunção Cognitiva/genética , Humanos , Imageamento por Ressonância Magnética , Redes Neurais de ComputaçãoRESUMO
Polyoxometalates (POMs) are known for their photocatalytic hydrogen production activity, but their solubility and limited stability often restrict their practical applications. Herein, we designed and solvothermally synthesized two new Cu-H2bpz (3,3',5,5'-tetramethyl-4,4'-bipyrazole, abbreviated as H2bpz) compounds, namely, Cu0.5(H2bpz)(NO3) (1) and Cu(Hbpz)(Cl)·DMF (2), and three new polyoxometalate-based Cu(II)-pyrazolate compounds, namely, Cu(PW12O40)0.5(H2bpz)2(H2O)·(OH)0.5(H2O)5.5 (3), Cu(HPMo12O40)(H2bpz)2(H2O)2·(H2O)4 (4), and Cu2(SiW12O40)(H2bpz)3(H2O)3·(H2O)6 (5). Compound 3 (Cu(PW12O40)0.5(H2bpz)2(H2O)·(OH)0.5(H2O)5.5) exhibits the best photocatalytic activity of 44.4 µ L h-1 g-1, which may be related to the stability of compounds. Herein, the solvothermal method has been proven to be an effective method in synthesizing stable organic-inorganic hybrid compounds with soluble POMs, metal ions, and organic ligands. Thus, heterogeneous catalysts with outstanding solar-light-driven photocatalytic properties were obtained.
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When the target biorecognition-triggered assembly of two Mg2+-dependent DNAzymes (MNAzymes) is employed for dually catalytic release of peroxidase-mimicking G-quadruplex DNAzymes (G-DNAzymes), this work develops a novel homogeneous colorimetric method for an ultrasensitive bioassay of platelet-derived growth factor-BB (PDGF-BB). The first MNAzyme assembly is realized through a highly specific aptamer biorecognition-driven proximity ligation reaction. Its catalytic cleavage toward the two designed hairpin substrates not only releases a large amount of G-DNAzymes for colorimetric signal transduction but also enables the spontaneous assembly of another MNAzyme for signal amplification. This leads to the successful detection of PDGF-BB in a wide linear range from 2.0 pg mL-1 to 20 ng mL-1 with a very low detection down to 0.088 pg mL-1. As the whole reactions including aptamer biorecognitions, DNA hybridizations, and catalytic cleavages of MNAzymes are conducted in a homogeneous solution, this method has very simple manipulations and also has high repeatability. In addition, the high specificity of the aptamer biorecognition-triggered signal transduction decides the excellent selectivity of the method. This bioassay does not require an expensive instrument and nucleic acid labeling for signal readout or any nanomaterial, enzyme, or nuclease for signal amplification. Thus, it displays an extensive potential for clinical diagnostic applications.
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DNA Catalítico/metabolismo , Magnésio/metabolismo , Fator de Crescimento Derivado de Plaquetas/análise , Biocatálise , Colorimetria , Quadruplex G , Humanos , Fator de Crescimento Derivado de Plaquetas/metabolismoRESUMO
Single-molecule functional materials with luminescence tunable by external stimuli are of increasing interest due to their application in sensors, display devices, biomarkers, and switches. Herein, new europium and samarium complexes with ligands having triphenylamine (TPA) groups as the redox center and 2,2'-bipyridine (bpy) as the coordinating groups and diketonate (tta) as the second ligand have been constructed. The complexes show white-light emission in selected solvents for proper mixtures of the emission from Ln3+ ions and the ligands. Meanwhile, they exhibit reversible luminescence switching on/off properties by controlling the external potential owing to intramolecular energy transfer from the Ln3+ ions to the electrochemically generated radical cation of TPAâ¢+. Time-dependent density functional theory (TD-DFT) calculations have been performed to study the electronic spectra. The proposed intramolecular energy transfer processes have been verified by density functional theory (DFT) studies.
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Hydrogen ions are ideal charge carriers for rechargeable batteries due to their small ionic radius and wide availability. However, little attention has been paid to hydrogen-ion storage devices because they generally deliver relatively low Coulombic efficiency as a result of the hydrogen evolution reaction that occurs in an aqueous electrolyte. Herein, we successfully demonstrate that hydrogen ions can be electrochemically stored in an inorganic molybdenum trioxide (MoO3 ) electrode with high Coulombic efficiency and stability. The as-obtained electrode exhibits ultrafast hydrogen-ion storage properties with a specific capacity of 88â mA hg-1 at an ultrahigh rate of 100 C. The redox reaction mechanism of the MoO3 electrode in the hydrogen-ion cell was investigated in detail. The results reveal a conversion reaction of the MoO3 electrode into H0.88 MoO3 during the first hydrogen-ion insertion process and reversible intercalation/deintercalation of hydrogen ions between H0.88 MoO3 and H0.12 MoO3 during the following cycles. This study reveals new opportunities for the development of high-power energy storage devices with lightweight elements.
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The rechargeable lithium-sulfur battery is recognized as a promising candidate for electrochemical energy storage system because of their exceptional advance in energy density. However, the fast capacity decay of sulfur cathode caused by polysulfide dissolution and low specific capacity caused by poor electrical conductivity still impede the further development of lithium-sulfur battery. To address above issues, this study reports the synthesis of feather duster-like TiO2 architecture by in situ growth of TiO2 nanowires on carbon cloth and further evaluates as sulfur host material. The strong chemical binding interaction between the polysulfides and TiO2 feather duster efficiently restrains the shuttle effect, leading to enhanced electrochemical kinetics. Besides, the in situ grown TiO2 NWs array also supply high surface for sulfur-loading and fast path for electron transfer and ion diffusion. As results, the novel CC/TiO2 /S composite cathode exhibits a high capacity of 608 mA h g-1 at 1.0 C after 700 cycles corresponding to capacity decay as low as 0.045% per cycle with excellent Coulombic efficiency higher than 99.5%.
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We present a novel framework named NeuralRecon for real-time 3D scene reconstruction from a monocular video. Unlike previous methods that estimate single-view depth maps separately on each key-frame and fuse them later, we propose to directly reconstruct local surfaces represented as sparse TSDF volumes for each video fragment sequentially by a neural network. A learning-based TSDF fusion module based on gated recurrent units is used to guide the network to fuse features from previous fragments. This design allows the network to capture local smoothness prior and global shape prior of 3D surfaces when sequentially reconstructing the surfaces, resulting in accurate, coherent, and real-time surface reconstruction. The fused features can also be used to predict semantic labels, allowing our method to reconstruct and segment the 3D scene simultaneously. Furthermore, we purpose an efficient self-supervised fine-tuning scheme that refines scene geometry based on input images through differentiable volume rendering. This fine-tuning scheme improves reconstruction quality on the fine-tuned scenes as well as the generalization to similar test scenes. The experiments on ScanNet, 7-Scenes and Replica datasets show that our system outperforms state-of-the-art methods in terms of both accuracy and speed.
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Nano-biochar, characterized by its environmentally friendly nature and unique nanostructure, offers a promising avenue for sustainable carbon materials. With its small particle size, large specific surface area, abundant functional groups and tunable pore structure, nano-biochar stands out due to its distinct physical and chemical properties compared to conventional biochar. This paper aims to provide an in-depth exploration of nano-biochar, covering its sources, transformation mechanisms, properties, applications, and areas requiring further research. The discussion begins with an overview of biomass sources for nano-biochar production and the conversion processes involved. Subsequently, primary synthesis methods and strategies for functionalization enhancement are examined. Furthermore, the applications of nano-biochar in catalysis, energy storage, and pollutant adsorption and degradation are explored and enhanced in various fields.
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BACKGROUND: Although exposure to greenness has generally benefited human metabolic health, the association between greenness exposure and metabolic obesity remains poorly studied. We aimed to investigate the associations between residential greenness and obesity phenotypes and the mediation effects of air pollutants and physical activity (PA) level on the associations. METHODS: We used the baseline of the China Multi-Ethnic Cohort (CMEC) study, which enrolled 87,613 adults. Obesity phenotypes were defined based on obesity and metabolic status, including metabolically unhealthy obesity (MUO), non-obesity (MUNO), metabolically healthy obesity (MHO), and non-obesity (MHNO). Greenness exposure was measured as the 3-year mean values of the normalized difference vegetation index (NDVI) and enhanced vegetation index (EVI) within the 500-m buffer zones around the participants' residence. Multivariable logistic regression was used to estimate the associations between greenness and obesity phenotypes. Stratified analyses by age, sex, educational level, and urbanicity were performed to identify how the effect varies across different subgroups. Causal mediation analysis was used to examine the mediation effects of air pollutants and PA level. RESULTS: Compared with MHNO, each interquartile range (IQR) increase in greenness exposure was associated with reduced risks of MHO (ORNDVI [95% CI] = 0.87 [0.81, 0.93]; OREVI = 0.91 [0.86, 0.97]), MUO (ORNDVI = 0.83 [0.78, 0.88]; OREVI = 0.86 [0.81, 0.91]), and MUNO (ORNDVI = 0.88 [0.84, 0.91]; OREVI = 0.89 [0.86, 0.92]). For each IQR increase in both NDVI and EVI, the risks of MHO, MUO, and MUNO were reduced more in men, participants over 60 years, those with a higher level of education, and those living in urban areas, compared to their counterparts. Concentrations of particulate matter (PM) and PA level partially mediated the associations between greenness exposure and obesity phenotypes. CONCLUSIONS: Exposure to residential greenness was associated with decreased risks of MHO, MUO, and MUNO, which was mediated by concentrations of PM and PA level, and modified by sex, age, educational level, and urbanicity.
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Obesidade , Fenótipo , Humanos , Masculino , China/epidemiologia , Feminino , Obesidade/epidemiologia , Pessoa de Meia-Idade , Adulto , Características de Residência/estatística & dados numéricos , Exercício Físico , Poluentes Atmosféricos/efeitos adversos , Poluentes Atmosféricos/análise , Idoso , Meio Ambiente , Estudos de Coortes , Exposição Ambiental/efeitos adversos , Poluição do Ar/efeitos adversosRESUMO
The best research-cell efficiency of perovskite solar cells (PSCs) is comparable with that of mature silicon solar cells (SSCs); However, the industrial development of PSCs lags far behind SSCs. PSC is a multiphase and multicomponent system, whose consequent interfacial energy loss and carrier loss seriously affect the performance and stability of devices. Here, by using spinodal decomposition, a spontaneous solid phase segregation process, in situ introduces a poly(3-hexylthiophene)/perovskite (P3HT/PVK) heterointerface with interpenetrating structure in PSCs. The P3HT/PVK heterointerface tunes the energy alignment, thereby reducing the energy loss at the interface; The P3HT/PVK interpenetrating structure bridges a transport channel, thus decreasing the carrier loss at the interface. The simultaneous mitigation of energy and carrier losses by P3HT/PVK heterointerface enables n-i-p geometry device a power conversion efficiency of 24.53% (certified 23.94%) and excellent stability. These findings demonstrate an ingenious strategy to optimize the performance of PSCs by heterointerface via Spinodal decomposition.
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DNA molecules that store genetic information in living creatures can be repurposed as building blocks to construct artificial architectures, ranging from the nanoscale to the microscale. The precise fabrication of self-assembled DNA nanomaterials and their various applications have greatly impacted nanoscience and nanotechnology. More specifically, the DNA origami technique has realized the assembly of various nanostructures featuring rationally predesigned geometries, precise addressability, and versatile programmability, as well as remarkable biocompatibility. These features have elevated DNA origami from academic interest to an emerging class of drug delivery platform for a wide range of diseases. In this minireview, the latest advances in the burgeoning field of DNA-origami-based innovative platforms for regulating biological functions and delivering versatile drugs are presented. Challenges regarding the novel drug vehicle's safety, stability, targeting strategy, and future clinical translation are also discussed.
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Biochar is preferentially recommended for the remediation of heavy metal-polluted soils. Sunflower is an important high-biomass oil crop with a promising potential for phytoremediation of Cr(VI)-polluted soil. However, how biochar affects sunflower growth and Cr accumulation in Cr(VI)-polluted soil needs to be elucidated. Here, a pot culture experiment was conducted to study whether soil amendment with biochar (0, 0.1%, 1%, and 5%, w/w) can mitigate Cr toxicity and accumulation in sunflower seedlings grown in soils artificially polluted with different levels of Cr(VI) (0, 50, and 250 mg Cr(VI)/kg soil). The addition of Cr(VI) exhibited significant phytotoxicity, as evidenced by inhibited plant growth and even the death of seedlings at 250 mg/kg Cr(VI). Overall, biochar amendment showed positive effects on plant growth and Cr immobilization, dependent on both the biochar dose and Cr addition level. When 50 mg/kg Cr(VI) was added, 1% biochar showed positive effects similar to 5% biochar on improving plant growth and mineral nutrition (particularly K), reducing Cr content in shoots and roots, and decreasing Cr availability and Cr(VI) content in the soil. In comparison with non-amendment, 1% and 5% biochar caused 85% and 100% increase in shoot dry weights, and 75% and 86% reduction in shoot Cr concentrations, respectively. When 250 mg/kg Cr(VI) was added, a 5% dose produced much better benefits than 1%, while a 0.1% dose did not help plants to survive. Overall, an appropriate dose of biochar enhanced Cr(VI) immobilization and subsequently decreased its toxicity and accumulation in sunflower seedlings. Our findings confirm that biochar can be used as an efficient amendment for the remediation of Cr(VI)-polluted soils and cleaner production of sunflower oil and biomass.
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Battery performance at subzero is restricted by sluggish interfacial kinetics. To resolve this issue, potassium-based dual-ion batteries (K-DIBs) based on the polytriphenylamine (PTPAn) cathode with anion storage chemistry and the hydrogen titanate (HTO) anode with K+ /solvent co-intercalation mechanism are constructed. Both the PTPAn cathode and the HTO anode do not undergo the desolvation process, which can effectively accelerate the interfacial kinetics at subzero. As revealed by theoretical calculations and experimental analysis, the strong K+ /solvent binding energy in the dilute electrolyte, the charge shielding effect of the crystal water, and the uniform SEI layer with high content of the flexible organic species synergically promote HTO to undergo K+ /solvent co-intercalation behavior. The special co-intercalation mechanism and anion storage chemistry enable HTO||PTPAn K-DIBs with superior rate performance and cycle durability, maintaining a capacity retention of 94.1% after 6000 cycles at -40 °C and 91% after 1000 cycles at -60 °C. These results provide a step forward for achieving high-performance energy storage devices at low temperatures.
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Background: Nuss procedure is the most common method of surgical treatment to pectus excavatum (PE). A significant percentage of surgeons choose to use thoracoscopic assistance during the Nuss procedure (TNP) to avoid cardiac injury. However, our previous findings confirm the safety of single incision Non-thoracoscopic Nuss Procedure (SINTNP). Hence, Further studies, particularly prospective randomized controlled trials, are necessary to assess the value of SINTNP for PE. Methods: This study is a prospective, superiority, multicenter, non-masked, randomized controlled trial that investigates the outcome and hospitalization medical expense of SINTNP compared to TNP for PE. A total of 320 eligible patients according to sample size calculation by retrospective data will be randomly assigned to the SINTNP group or the TNP group at a 1:1 ratio using stratified blocked randomization and the zone length was set as four. Patients aged between 3 and 18 years old for the first surgery and without combination of complex anomalies such as Marfan syndrome and congenital heart disease will be considered for the study. The co-primary endpoint is thoracic related complications and medical expense during hospitalization. Thoracic related complications were defined as pneumothorax, pleural effusion, pneumonia and incision infection. The secondary endpoints include surgery duration and length of hospital stay.The registration number for this study protocol is ChiCTR230073081 (Chinese Clinical Trial Registry, A Primary Registry of International Clinical Trial Registry Platform, World Health Organization).
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ZnIn2S4/ZnO heterostructures have been achieved by a simple in-situ growth solvothermal method. Under full spectrum irradiation, the optimal photocatalyst 2ZnIn2S4/ZnO exhibits H2 evolution rate of 13,638 (water/ethanol = 1:1) and 3036 (water) µmol·g-1h-1, which is respectively 4 and 5 times higher than that of pure ZnIn2S4. In situ illumination X-ray photoelectron spectroscopy (ISI-XPS) analysis and density functional theory (DFT) calculations show that the electrons of ZnIn2S4 are removed to ZnO through hybridization and form an internal electric field between ZnIn2S4 and ZnO. The optical properties of the catalyst and the effect of internal electric field (IEF) can increase photo-generated electrons (e-)-holes (h+) transport rate and enhance light collection, resulting in profitable photocatalytic properties. The photoelectrochemical and EPR results show that a stepped (S-scheme) heterojunction is formed in the ZnIn2S4/ZnO redox center, which greatly promotes separation of e--h+ pairs and efficient H2 evolution. This research offers an effective method for constructing an efficient S-Scheme photocatalytic system for H2 evolution.
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Hemagglutinin (HA) of influenza A has been reported as the key protein in viral infection. Therefore, the density and the dynamic pattern of this protein in viral envelope will affect the virus to infect target cells. We used a lentiviral system to study the influenza A H1N1 viral infection. Herein we demonstrate that the influenza non-structural proteins (NS) significantly promote viral infection. By substituting NS gene segment from an H1N1 genome set of A/WSN/1933 with the NS segment isolated from another H1N1 substrain genome set, China246, we found that viral infection tropism was significantly altered. The reassortant H1N1 shows almost identical infectivity compared with its parental virus, A/WSN/1933, for the human epithelial cell line HOT, but shows only 1/100 infectivity of its parental virus when infecting the Madin-Darby canine kidney (MDCK) cell line. These results suggest that not only is NS important in the infectivity of human influenza virus, but that it may play a critical role in viral tropism, allowing the virus to mutate and spread to other species.