Highly dispersed Au nanoparticles supported on Ni–Al mixed metal oxides (Au/NiAl-MMO) were prepared by a facile method, which is significantly efficient for the aerobic oxidation of ethyl lactate ...using authentic air as the oxidant, achieving 72.6% ethyl lactate conversion and 88.3% selectivity to ethyl pyruvate at 240 °C in a continuous fixed-bed reactor. The catalyst retained its catalytic performance during a long-term stability test. Characterization and experimental studies on the kinetic dependence sequence of the reactants and elementary reaction steps confirmed that the Au/NiAl-MMO catalyst followed the Mars–van Krevelen mechanism, with the activation of O
2
as the elementary step. The quasi in situ X-ray photoelectron spectroscopy spectra demonstrated that the active sites in the Au/NiAl-MMO catalyst were Au nanoparticles. This work may provide a novel technique for developing more efficient supported metal catalysts for the aerobic oxidation of ethyl lactate using authentic air as the oxidant.
Graphical abstract
Highly dispersed Au nanoparticle catalyst was facilely prepared for the efficient catalytic oxidation of ethyl lactate with authentic air.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Flavin mononucleotide (FMN) is well known as a cofactor of riboflavin and plays key roles in metabolisms. Self-assembly is one of the most important approaches for maintaining the biological ...functions of FMN. In this work, a supramolecular self-assembly nano-system driven by non-covalent interactions between a water-soluble polythiophene (PMT-1) and FMN is constructed in 100% aqueous solution. In this system, π-stacked nano-aggregates have been formed and the self-assembly process of PMT-1 and FMN has been explored through UV-Vis, fluorescence, and circular dichroism (CD) spectroscopy. The synergistic effect of non-covalent interactions containing electrostatic, hydrophobic and π-π interactions is proposed to account for the formation of PMT-1/FMN nano-superstructures. Furthermore, colorimetric responses of PMT-1 promote the sensing applications of this approach for the rapid and visual detection of FMN. It features wide detection range, fast response, high sensitivity and selectivity. The LOD in buffer and actual sample could be as low as 1.1 and 32 nM, respectively.
Self-assembly of flavin mononucleotide and a cationic polythiophene in 100% aqueous media with colorimetric and fluorescence dual responses.
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection has been detected in almost all organs of coronavirus disease-19 patients, although some organs do not express ...angiotensin-converting enzyme-2 (ACE2), a known receptor of SARS-CoV-2, implying the presence of alternative receptors and/or co-receptors. Here, we show that the ubiquitously distributed human transferrin receptor (TfR), which binds to diferric transferrin to traffic between membrane and endosome for the iron delivery cycle, can ACE2-independently mediate SARS-CoV-2 infection. Human, not mouse TfR, interacts with Spike protein with a high affinity (K
~2.95 nM) to mediate SARS-CoV-2 endocytosis. TfR knock-down (TfR-deficiency is lethal) and overexpression inhibit and promote SARS-CoV-2 infection, respectively. Humanized TfR expression enables SARS-CoV-2 infection in baby hamster kidney cells and C57 mice, which are known to be insusceptible to the virus infection. Soluble TfR, Tf, designed peptides blocking TfR-Spike interaction and anti-TfR antibody show significant anti-COVID-19 effects in cell and monkey models. Collectively, this report indicates that TfR is a receptor/co-receptor of SARS-CoV-2 mediating SARS-CoV-2 entry and infectivity by likely using the TfR trafficking pathway.
Palladium hydrides (PdH x ) are pivotal in both fundamental research and practical applications across a wide spectrum. PdH x nanocrystals, synthesized by heating in dimethylformamide (DMF), exhibit ...remarkable stability, granting them widespread applications in the field of electrocatalysis. However, this stability appears inconsistent with their metastable nature. The substantial challenges in characterizing nanoscale structures contribute to the limited understanding of this anomalous phenomenon. Here, through a series of well-conceived experimental designs and advanced characterization techniques, including aberration-corrected scanning transmission electron microscopy (AC-STEM), in situ X-ray diffraction (XRD), and time-of-flight secondary ion mass spectrometry (TOF-SIMS), we have uncovered evidence that indicates the presence of C and N within the lattice of Pd (PdC x N y ), rather than H (PdH x ). By combining theoretical calculations, we have thoroughly studied the potential configurations and thermodynamic stability of PdC x N y , demonstrating a 2.5:1 ratio of C to N infiltration into the Pd lattice. Furthermore, we successfully modulated the electronic structure of Pd nanocrystals through C and N doping, enhancing their catalytic activity in methanol oxidation reactions. This breakthrough provides a new perspective on the structure and composition of Pd-based nanocrystals infused with light elements, paving the way for the development of advanced catalytic materials in the future.
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IJS, KILJ, NUK, PNG, UL, UM
Recently, transition metal dichalcogenides have been extensively studied as new functional materials for electronic and optoelectronic applications. Most initial efforts have been focused on several ...members of this material family with 2H lattice structure. ReSe
as a less-study transition metal dichalcogenide has gained significant momentum due to its 1T lattice structure and in-plane anisotropic electronic and optical properties. Extensive efforts have shown its promising future as a novel material for optoelectronics. However, little was known about the photocarrier dynamics in this material. Here we report the first transient absorption measurement of photocarrier dynamics in ReSe
bulk and monolayer sample in reflection geometry. We observed ultrafast thermalization and relaxation of hot carriers in bulk ReSe
, and obtained a photocarrier lifetime on the order of 80 ps and decreases slightly with increasing the carrier density. Pronounced anisotropic response of differential reflection was observed. We also studied monolayer ReSe
samples obtained by chemical vapor deposition and deduced a photocarrier lifetime on the order of 10 ps. These results provide fundamental information for using this material in various optoelectronic devices.
Abstract
Metal phosphorous tri‐chalcogenides are a category of new ternary 2D layered materials with a wide range of tuneable bandgaps (1.2–3.5 eV). These wide‐bandgap semiconductors exhibit great ...potential applications in solar‐blind ultraviolet (SBUV) photodetection. However, these 2D solar‐blind photodetectors suffer from low photoresponsivity, slow photoresponse speed, and narrow operation spectral region, thereby limiting their practical applications. Here, an ultra‐broadband photodetection based on a FePSe
3
/MoS
2
heterostructure with coverage ranging from solar‐blind ultraviolet 265 nm to longwave infrared (LWIR) 10.6 µm is reported. Notably, the device exhibits excellent weak light detection capability. A high photoresponsivity of 33 600 A W
−1
and an external quantum efficiency of 1.57 × 10
7
% are demonstrated. A noise‐equivalent power as low as 5.7 × 10
–16
W Hz
−1/2
and a specific detectivity up to 1.51 × 10
13
cm Hz
1/2
W
−1
are realized in the SBUV region. The room temperature LWIR photoresponsivity of 0.12 A W
−1
is realized. This work opens a route to design high‐performance SBUV photodetectors and wide spectral photoresponse applications.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
It is unclear whether multifocal soft contact lenses (MFSCLs) affect visual quality when they are used for myopia control in juvenile myopes. The aim of this study was, therefore, to investigate the ...effect of MFSCLs on visual quality among juvenile myopia subjects.
In a prospective, intervention study, thirty-three juvenile myopes were enrolled. Visual perception was assessed by a quality of vision (QoV) questionnaire with spectacles at baseline and after 1 month of MFSCL wear. At the one-month visit, the high (96%) contrast distance visual acuity (distance HCVA) and low (10%) contrast distance visual acuity (distance LCVA) were measured with single vision spectacle lenses, single vision soft contact lenses (SVSCLs) and MFSCLs in a random order. Wavefront aberrations were measured with SVSCLs, with MFSCLs, and without any correction.
Neither distance HCVA (
> 0.05) nor distance LCVA (
> 0.05) revealed any significant difference between MFSCLs, SVSCLs and single vision spectacle lenses. The overall score (the sum of ten symptoms) of the QoV questionnaire did not show a statistically significant difference between spectacles at baseline and after 1 month of MFSCL wear (
= 0.357). The results showed that the frequency (
< 0.001), severity (
= 0.001) and bothersome degree (
= 0.016) of halos were significantly worse when wearing MFSCLs than when wearing single vision spectacle lenses. In contrast, the bothersome degree caused by focusing difficulty (
= 0.046) and the frequency of difficulty in judging distance or depth perception (
= 0.046) were better when wearing MFSCLs than when wearing single vision spectacle lenses. Compared with the naked eye, MFSCLs increased the total aberrations (
< 0.001), higher-order aberrations (
< 0.001), trefoil (
= 0.023), coma aberrations (
< 0.001) and spherical aberrations (SA) (
< 0.001). Compared with the SVSCLs, MFSCLs increased the total aberrations (
< 0.001), higher-order aberrations (
< 0.001), coma aberrations (
< 0.001) and SA (
< 0.001). The direction of SA was more positive (
< 0.001) with the MFSCLs and more negative (
= 0.001) with the SVSCLs compared with the naked eye.
Wearing MFSCLs can provide satisfactory corrected visual acuity (both distance HCVA and distance LCVA). Although the lenses increased the aberrations, such as total aberrations and higher-order aberrations, there were few adverse effects on the distance HCVA, distance LCVA and visual perception after 1 month of MFSCL use.
Chinese Clinical Trial Registry: ChiCTR-OOC-17012103. Registered 23 July 2017, http://www.chictr.org.cn/usercenter.aspx.
In the context of the continuous development of urbanization and global climate change, urban flooding risk has become a well-publicized research issue. The Storm Water Management Model (SWMM) ...performs very well in urban rain-runoff simulations and is widely used to build flood models in specific areas. Because of the complicated and tedious processing work for urban flood modeling and simulation, multifield participants’ cooperation is becoming a trend. To promote the research and application of flood modeling and simulation, some resource sharing-oriented systems and platforms have been proposed with the advantages of network technology. However, they still require a participatory environment that can help modeling participants overcome the difficulties of distributed cooperation in the process of SWMM-based flood modeling and simulation. Therefore, we designed and implemented an online participatory system to coordinate the effective collaboration of modeling participants in this process. By referring to the scenarios and specific participatory demands in the modeling process, the system provides a guiding framework that consists of multiple participatory activities and prepares a series of online auxiliary tools designed for these activities. Using the main urban area of Lishui City as the study area, it was confirmed that the process of SWMM-based flood modeling and simulation can be demonstrated collaboratively on the online participatory system developed in this study.
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CEKLJ, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Ustiloxins are cyclopeptide mycotoxins produced by the pathogenic fungus Villosiclava virens of rice false smut. Ustiloxins A and B as two main mycotoxins were determined conveniently by LC-ESI-MS in ...the water extract from rice false smut balls which were mostly composed of the chlamydospores and mycelia of the pathogen. Both ustiloxins A and B in the water extract were also quantitatively analyzed by HPLC. This is the first report on the determination and analysis of ustiloxins A and B simultaneously by LC-ESI-MS and HPLC in false smut balls of rice.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Objectives
To evaluate the prevalence of Helicobacter pylori infection and risk factors and to serotype the strains in Wuwei, located in north‐western China, which has a high incidence of gastric ...cancer.
Methods
Helicobacter pylori infection was analysed in 21 291 adults by 14C‐urea breath test, and H. pylori antibody were detected in 9183 serum samples by latex immunoturbidimetric method. The correlation of H. pylori infection with demographic–economic, lifestyle factors and medical history among the participants was determined by questionnaire. The antibodies against H. pylori urease, VacA and CagA in serum were determined by dot immunobinding assay.
Results
The infection rate of H. pylori was 53.0%, and 90.1% of strains were type I strains. The H. pylori infection rate was higher among farmers (OR = 1.34, 95% CI: 1.19–1.50) and individuals who had a junior high school or higher education level (OR = 1.10, 95% CI: 1.06–1.15), and was lower in older individuals (OR = 0.86, 95% CI: 0.83–0.90), individuals with high income (OR = 0.93, 95% CI: 0.90–0.95), individuals with a habit of eating quickly (OR = 0.93, 95% CI: 0.87–0.99) and individuals who consumed more fruit and vegetables (OR = 0.90, 95% CI: 0.85–0.95). Individuals with history of cholecystitis/cholecystolithiasis, hypertension and asthma were negatively correlated with H. pylori infection (P < 0.05).
Conclusion
The prevalence of H. pylori infection is high in Wuwei. The major prevalent strain is type I strain. Age, education, occupation, household income, consumption of fruit and vegetables, and habit of eating quickly are independent risk factors for H. pylori infection, which is also associated with individuals with a history of extragastric diseases.
Objectifs
Evaluer la prévalence de l'infection à Helicobacter pylori et les facteurs de risque et déterminer le sérotype des souches à Wuwei, situé dans le nord‐ouest de la Chine, où l'incidence du cancer gastrique est élevée.
Méthodes
L'infection à H. pylori a été analysée chez 21.291 adultes par un test respiratoire à l'urée au 14C, et des anticorps à H. pylori ont été détectés dans 9.183 échantillons de sérum par une méthode immuno‐turbidimétrique au latex. La corrélation entre l'infection à H. pylori et les facteurs démographiques et économiques, le mode de vie et les antécédents médicaux des participants a été déterminée par un questionnaire. Les anticorps contre l’uréase de H. pylori, VacA et CagA dans le sérum ont été déterminés par un test dot par d'immuno‐liaison.
Résultats
Le taux d'infection à H. pylori était 53,0% et 90,1% des souches étaient du type I. Le taux d'infection à H. pylori est plus élevé chez les agriculteurs (OR = 1,34 ; IC95%: 1,19 à 1,50) et les personnes qui avaient un niveau d'instruction du premier cycle secondaire ou supérieur (OR = 1,10 ; IC95%: 01,06 à 01,15) et était plus faible chez les personnes âgées (OR = 0,86 ; IC95%: 0,83‐0,90), les personnes à revenu élevé (OR = 0,93 ; IC95%: 0,90‐0,95), les personnes ayant l'habitude de manger rapidement (OR = 0,93 ; IC9 %: 0,87‐0,99) et les individus qui consommaient plus de fruits et de légumes (OR = 0,90 ; IC95%: 0,85‐0,95). Les personnes ayant des antécédents de cholécystite/cholécystolithiase, d'hypertension et d'asthme avaient une corrélation négative avec l'infection à H. pylori (p <0,05 ).
Conclusion
La prévalence de l'infection à H. pylori est élevée à Wuwei. La principale souche répandue est du type I. L'âge, l'éducation, la profession, le revenu du ménage, la consommation de fruits et de légumes et l'habitude de manger rapidement sont des facteurs de risque indépendants d'infection à H. pylori, qui est également associée à des personnes ayant des antécédents de maladies extra‐gastriques.
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FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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