UiO‐66, a zirconium based metal–organic framework, is incorporated with nanosized carbon nitride nanosheets via a facile electrostatic self‐assembly method. This hybrid structure exhibits a large ...surface area and strong CO2 capture ability due to the introduction of UiO‐66. We demonstrate that electrons from the photoexcited carbon nitride nanosheet can transfer to UiO‐66, which can substantially suppress electron–hole pair recombination in the carbon nitride nanosheet, as well as supply long‐lived electrons for the reduction of CO2 molecules that are adsorbed in UiO‐66. As a result, the UiO‐66/carbon nitride nanosheet heterogeneous photocatalyst exhibits a much higher photocatalytic activity for the CO2 conversion than that of bare carbon nitride nanosheets. We believe this self‐assembly method can be extended to other carbon nitride nanosheet loaded materials.
A novel carbon nitride nanosheet heterogeneous photocatalyst is fabricated via a facile electrostatic self‐assembly method. Electrons from the photoexcited carbon nitride nanosheets can transfer to UiO‐66, which can substantially suppress electron–hole pair recombination in the carbon nitride nanosheet, as well as supply long‐lived electrons for the reduction of CO2 molecules adsorbed in UiO‐66.
Hypervirulent
(hvKP) has spread globally since first described in the Asian Pacific Rim. It is an invasive variant that differs from the classical
(cKP), with hypermucoviscosity and hypervirulence, ...causing community-acquired infections, including pyogenic liver abscess, pneumonia, meningitis, and endophthalmitis. It utilizes a battery of virulence factors for survival and pathogenesis, such as capsule, siderophores, lipopolysaccharide, fimbriae, outer membrane proteins, and type 6 secretion system, of which the former two are dominant. This review summarizes these hvKP-associated virulence factors in order to understand its molecular pathogenesis and shed light on new strategies to improve the prevention, diagnosis, and treatment of hvKP-causing infection.
The role of rivers as a major transport pathway for all sizes of plastic debris into the ocean is widely recognized. Global modelling studies ranked the Changjiang River as the largest contributor of ...plastic waste to the marine environment, but these estimates were based on insufficient empirical data. To better understand the role of rivers in delivering terrestrial plastic debris to the ocean, the spatial and temporal patterns of microplastics (MP) in the Changjiang Estuary (CE) and the East China Sea (ECS) were studied based on surface water samples in February, May, and July 2017. A total of 3225 MP (60–5000 μm) were identified by Fourier-transform infrared (FTIR) spectrometry. MP abundance in July was higher than in February and May due to higher river discharge. Density stratification in CE significantly influenced the surface MP abundances. A temporal accumulation zone within the river-sea interface for plastics was indicated by stations with apparently higher abundances in the river plume. Fibers were the most common MP (>80%) over three months. Small MP (<1000 μm) composed 75.0% of the total plastics on average. The average mass of MP was 0.000033 g/particle, which was two orders of magnitude lower than the empirical mass in literature. Without considering tidal effects, we estimate 16–20 trillion MP particles, weighing 537.6–905.9 tons, entered the sea through the surface water layer of the Changjiang River in 2017. These findings of this study provide reliable information on MP waste in a large river, which should be considered in further studies for estimating the riverine plastic loads.
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•MP abundance and size exhibited distinct seasonality in the Changjiang Estuary.•A ‘Patchiness’ in distribution of MP were observed in the Changjiang River plume.•The water density stratification impacted suspended microplastic abundances.•MP in our study averagely weighed 0.000033 g.•The annually MP load in the top layer of the Changjiang River is 537.6–905.9 tons.
The planning and control of wind power production rely heavily on short-term wind speed forecasting. Due to the non-linearity and non-stationarity of wind, it is difficult to carry out accurate ...modeling and prediction through traditional wind speed forecasting models.
In the paper, we combine empirical mode decomposition (EMD), feature selection (FS), support vector regression (SVR) and cross-validated lasso (LassoCV) to develop a new wind speed forecasting model, aiming to improve the prediction performance of wind speed. EMD is used to extract the intrinsic mode functions (IMFs) from the original wind speed time series to eliminate the non-stationarity in the time series. FS and SVR are combined to predict the high-frequency IMF obtained by EMD. LassoCV is used to complete the prediction of low-frequency IMF and trend.
Data collected from two wind stations in Michigan, USA are adopted to test the proposed combined model. Experimental results show that in multi-step wind speed forecasting, compared with the classic individual and traditional EMD-based combined models, the proposed model has better prediction performance.
Through the proposed combined model, the wind speed forecast can be effectively improved.
Noncoding RNAs (ncRNAs) represent a large segment of the human transcriptome and have been shown to play important roles in cellular physiology and disease pathogenesis. Increasing evidence on the ...functional roles of ncRNAs in cancer progression emphasizes the potential of ncRNAs for cancer treatment. Here, we summarize the roles of ncRNAs in disease relapse and resistance to current standard chemotherapy and radiotherapy; the current research progress on ncRNAs for clinical and/or potential translational applications, including the identification of ncRNAs as therapeutic targets; therapeutic approaches for ncRNA targeting; and ncRNA delivery strategies in potential clinical translation. Several ongoing clinical trials of novel RNA-based therapeutics were also emphasized. Finally, we discussed the perspectives and obstacles to different target combinations, delivery strategies, and system designs for ncRNA application. The next approved nucleic acid drug to treat cancer patients may realistically be on the horizon.
A
bstract
We study the signal of long-lived sterile neutrino at the LHC produced through the decay of the
W
boson. It decays into charged lepton and jets. The characteristic signature is a hard ...prompt lepton and a lepton from the displaced decay of the sterile neutrino, which leads to a bundle of displaced tracks with large transverse impact parameter. Different from other studies, we neither reconstruct the displaced vertex nor place requirement on its invariant mass to maintain sensitivity for low sterile neutrino masses. Instead, we focus on the displaced track from the lepton. A difficulty for low mass sterile neutrino study is that the displaced lepton is usually
non-isolated
. Therefore, leptons from heavy flavor quark is the major source of background. We closely follow a search for displaced electron plus muon search at CMS and study their control regions, which is related to our signal regions, in great detail to develop a robust estimation of the background for our signals. After further optimization on the signal limiting the number of jets, low
H
T
and large lepton displacement
d
0
to suppress SM background, we reach an exclusion sensitivity of about 10
−8
(10
−5
) for the mixing angle square at 10 (2) GeV sterile neutrino mass respectively. The strategy we propose can cover the light sterile masses complimentary to beam dump and forward detector experiments.
•An analytical model of a 3D re-entrant auxetic cellular structure was established.•Overlapping of struts and axial extension/compression was taken into consideration.•Strut slenderness significantly ...influence on deformation mechanisms of structures.•Axial extension/compression play decisive role on the lateral Poisson's ratio.
In this work, an analytical model of a 3D re-entrant auxetic cellular structure has been established based on energy method. In the model the overlapping of the struts as well as axial extension or compression (mostly neglected in former studies) were taken into consideration to make the model applicable when the struts are relative stubby which is common in engineering designs. Analytical solutions for the modulus and Poisson's ratios of the cellular structure in all principal directions were deduced. To validate the analytical model in present study, numerical calculations using brick elements were performed on unit cell models with periodic boundary conditions, and comparisons of the present model with analytical formulae and experimental results available in former literatures were also conducted. The results show that when the struts are slender enough, the bending of the struts play decisive role on the deformation of the structure and other mechanisms can be ignored; while when the struts become relative stubby, all the mechanisms including bending, shearing and axial loading need to be considered; The often-ignored axial extension or compression term may even play decisive role on determining the lateral Poisson's ratio of the structure when the struts are relative stubby.
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The solar‐driven photocatalytic reduction of CO2 (CO2RR) into chemical fuels is a promising route to enrich energy supplies and mitigate CO2 emissions. However, low catalytic efficiency and poor ...selectivity, especially in a pure‐water system, hinder the development of photocatalytic CO2RR owing to the lack of effective catalysts. Herein, we report a novel atom‐confinement and coordination (ACC) strategy to achieve the synthesis of rare‐earth single erbium (Er) atoms supported on carbon nitride nanotubes (Er1/CN‐NT) with a tunable dispersion density of single atoms. Er1/CN‐NT is a highly efficient and robust photocatalyst that exhibits outstanding CO2RR performance in a pure‐water system. Experimental results and density functional theory calculations reveal the crucial role of single Er atoms in promoting photocatalytic CO2RR.
A catalyst with a high density of rare‐earth single Er atoms supported on a carbon nitride nanotube (HD‐Er1/CN‐NT) is synthesized by an atom‐confinement and coordination strategy (ACC). Experimental results and DFT calculations reveal that the single Er atoms play a key role in the photocatalytic CO2 reduction reaction in a pure‐water system. The ACC strategy also extends to the synthesis of other rare‐earth single‐atom catalysts.
The huge traffic of e-commerce platforms provides a wide market for stores, but the fierce competition among stores for onsite traffic increases the cost of onsite promotion for stores, and it also ...reduces the effectiveness of promotion. Therefore, more and more stores on e-commerce platforms are using content platforms for offsite promotion. In the face of stores’ onsite and offsite promotion behaviors, the choice of competition and cooperation strategies among participants in the promotion process is the key to solving the problem of increasing traffic. Accordingly, this paper constructs an onsite and offsite promotion decision model consisting of an e-commerce platform, a store on the e-commerce platform, and a content platform, and it compares the results based on the decentralized decision situation, centralized decision situation, and promotion investment sharing situation. In addition, some results are presented in more detail in the form of numerical analysis. The results show that the promotion investment sharing does not change the level of onsite promotion investment, but the centralized decision makes the onsite promotion investment decrease; promotion investment sharing and centralized decision scenarios increase the promotion investment of the e-commerce platform and the content platform. When the sum of the parts of promotion investments shared by the store and the content platform for the e-commerce platform is relatively small, each participant will be willing to participate in the promotion investment sharing agreement. We believe that this study will provide important implications for the resolution of stores’ traffic dilemmas on e-commerce platforms.
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