Soil particulate organic matter (POM) has rapid turnover and metal enrichment, but the interactions between organic matter (OM) and metals have not been well studied. The present study aimed to ...investigate changes in the OM concentration and composition of the POM fraction and their corresponding effects on metal distribution and extractability in long-term polluted paddy soils. Soil 2000–53 μm POM size fractions had higher contents of C–H and C=O bonds, C–H/C=O ratios and concentrations of fulvic acid (FA), humic acid (HA), cadmium (Cd) and zinc (Zn) than the bulk soils. Cadmium and Zn stocks in soil POM fractions were 24.5–27.9% and 7.12–16.7%, respectively, and were more readily EDTA-extractable. Compared with the control soil, the 2000–250 μm POM size fractions had higher organic carbon concentrations and C/N ratios in the polluted soils. However, there were no significant differences in the contents in C–H and C=O bonds or C–H/C=O ratios of POM fractions among the control, slightly and highly polluted soils. In accordance with the lower contents of C=O bonds and FA and HA concentrations, the Cd and Zn concentrations in 250–53 μm POM size fractions were lower than those in 2000–250 μm POM size fractions. Enrichment of Cd in POM fractions increased with increasing soil pollution level. These results support the view that changes in the OM concentration and the size and composition of POM fractions play a key role in determining the distribution of Cd and Zn in paddy soils.
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•The OC and FA contents and C/N in POM (2000–250 μm) increased in polluted soil.•Enrichment of Cd and Zn decreased with decreasing POM size.•No significant change in content of C=O group in POM was observed in polluted soil.•Changes in the size and composition of soil POM affected the Cd and Zn distribution.
Interactions between soil organic matter and metals.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
The electrochemical N2 fixation, which is far from practical application in aqueous solution under ambient conditions, is extremely challenging and requires a rational design of electrocatalytic ...centers. We observed that bismuth (Bi) might be a promising candidate for this task because of its weak binding with H adatoms, which increases the selectivity and production rate. Furthermore, we successfully synthesized defect‐rich Bi nanoplates as an efficient noble‐metal‐free N2 reduction electrocatalyst via a low‐temperature plasma bombardment approach. When exclusively using 1H NMR measurements with N2 gas as a quantitative testing method, the defect‐rich Bi(110) nanoplates achieved a 15NH3 production rate of 5.453 μg mgBi−1 h−1 and a Faradaic efficiency of 11.68 % at −0.6 V vs. RHE in aqueous solution at ambient conditions.
Beneficial defects: Defect‐rich bismuth nanoplates achieve a 15NH3 production rate of 5.453 μg mgBi−1 h−1 and a Faradaic efficiency of 11.68 % at −0.6 V vs. RHE in aqueous solutions at ambient conditions because of their poor binding with H adatoms, which increases the selectivity and production rate. Also, 1H NMR measurements with N2 gas ware used as a quantitative test method in aqueous electrolytes.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
This technical note investigates the controllability of networked dynamic systems of which some subsystems are not directly affected by external inputs (i.e., autonomous). The topology can be ...arbitrary, and every subsystem can have different dynamics and even different number of states, inputs and outputs. We show that to guarantee the controllability of the whole system, every subsystem should be controllable when isolated. We establish some necessary and sufficient conditions for the system to be controllable. These conditions essentially depend on the parameters of every subsystem separately or the strongly connected autonomous subsystems, which reduce significantly computation complexity for large-scale networked systems. We reveal that heterogenous networked systems under some assumptions can be separated into several independent subnetworks, such that the controllability of the whole system is equal to the controllability of each subnetwork. Based on these conditions, criteria that can be easily verified are given for the controllability of networked systems with some special topologies.
Exosomes are emerging as a new type of cancer biomarkers. Exosome is a bilayered nano-sized vesicle secreted by various living cells in all body fluids. Based on the expanding albeit incomplete ...knowledge of their biogenesis, secretion by cells and cancer cell-specific molecular and genetic contents, exosomes are viewed as promising, clinically-relevant surrogates of cancer progression and response to therapy. Preliminary proteomic, genetic and functional profiling of cancer cell-derived or cancer plasma-derived exosomes confirms their unique characteristics. Alterations in protein or nucleic acid profiles of exosomes in plasma correlate with pathological processes of many diseases including cancer. However, previous studies on exosome application in cancer diagnosis and treatment mainly focussed on miRNAs. With the development of rapid large-scale production, purification, extraction and screening of exosomal contents, exosomal protein application can be explored for early stage cancer diagnosis, monitoring and prognosis evaluation. Here, we summarized the recent developments in application of exosomal proteins for cancer diagnosis.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
•A complete ABQ-based procedure for first-four moments estimation of PDF.•An efficient reliability method in conjunction with ABQ-based procedure and SGLD model.•Adaptive sampling scheme formulated ...to iteratively add new integration points.•Goodness of moments estimation guaranteed by prescribing a stopping condition.•The proposed method superior to existing ‘non-adaptive’ integration methods.
An efficient method for structural reliability analysis is presented, which combines the statistical moments estimation and a versatile probability distribution model, i.e., the shifted generalized lognormal distribution (SGLD) model. In this method, a complete adaptive Bayesian quadrature (ABQ)-based procedure is developed to evaluate the first-four central moments of the equivalent extreme value (EEV) of structural responses, where an adaptive sampling scheme is formulated to iteratively add new integration points so as to satisfy the prescribed accuracy requirement with as fewer deterministic response analyses as possible. The probability density function (PDF) of the EEV is then recovered by fitting the SGLD model using the estimated statistical moments. Finally, the structural reliability is obtained by a simple one-dimensional integral of the PDF of the EEV over the safe domain. To demonstrate the efficacy of the proposed methodology, two numerical examples are carried out, involving the statistical moments estimation of analytical functions with different mathematical characteristics and the dynamic reliability assessment of nonlinear stochastic structures subjected to seismic excitations. It is revealed that the proposed method is capable of attaining fairly desired reliability measures on engineering structures with satisfactory accuracy and efficiency.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this paper, two main kinds of the secondary, i.e., the solid and laminated back iron secondary, are applied in linear metro, as well as electromagnetic forces and secondary losses of the ...single-sided linear induction motor (SLIM) with different secondary are calculated by the finite-element method (FEM). First, in solving region, the fundamental equations of the magnetic field with eddy currents in the secondary are deduced, and specific boundary conditions for each part of SLIMs are given. Equations of the secondary loss and efficiency are presented. Second, 120-kW SLIMs with two types of the secondary for metro are calculated by the three-dimensional FEM, respectively. The efficiency and secondary loss are analyzed for different numbers of the lamination in the secondary back iron. The optimal number of the back iron lamination is then obtained. Third, considering the influence of the end and edge effect, the air gap flux density with different secondaries is calculated. Then, the thrust and vertical force are analyzed for SLIMs with two kinds of the secondary. Finally, numerical results of the efficiency, thrust, and vertical force, which are obtained from different secondaries, are experimentally validated by measurement on the test rig of the SLIM.
Although many methods and new therapeutic drugs have been developed, the overall survival rate and long‐term survival rate of patients with gastric cancer (GC) are still not satisfactory. In this ...study, we investigated the effects of microRNA miR‐133a‐3p and transcription factor FOXP3 on proliferation and autophagy of GC cells and their interactions. Our results showed that knockdown of FOXP3 increased the proliferation and autophagy of GC cells. The relationship between FOXP3 and autophagy has not been reported previously. In addition, FOXP3 could directly bind the promoter region of TP53 and inhibit its expression. miR‐133a‐3p increased the proliferation and autophagy via decreasing the protein level of FOXP3 by targeting its 3′‐UTR. Our research provides new insights into the development of GC and provides new ideas and theoretical basis for the clinical treatment of GC and the development of new drug targets.
miR‐133a‐3p increased the proliferation and autophagy via decreasing the protein level of FOXP3 by targeting its 3′‐untranslated region. Our research provides new insights into the development of gastric cancer and provides new ideas and theoretical basis for the clinical treatment of gastric cancer and the development of new drug targets.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Mucosa is a protective and lubricating barrier in biological tissue, which has a great clinical inspiration because of its slippery, soft, and hydrophilic surface. However, mimicking mucosal traits ...on complex surface remains an enormous challenge. Herein, a novel approach to create mucosa‐like conformal hydrogel coating is developed. A thin conformal hydrogel layer mimicking the epithelial layer is obtained by first absorbing micelles, followed by forming covalent interlinks with the polymer substrate via interface‐initiated hydrogel polymerization. The resulting coating exhibits uniform thickness (≈15 µm), mucosa‐matched compliance (Young's modulus = 1.1 ± 0.1 kPa) and lubrication (coefficients of friction = 0.018 ± 0.003), robust interfacial bonding against peeling (peeling strength = 1218.0 ± 187.9 J m–2), as well as high water absorption capacity. It effectively resists adhesion of proteins and bacteria without compromising biocompatibility. As demonstrated by an in vivo cynomolgus monkey model and clinical trial, applications of the mucosa‐like conformal hydrogel coating on the endotracheal tube significantly reduce intubation‐related complications, such as invasive stimuli, mucosal lesions, laryngeal edema, inflammation, and postoperative pain. This work offers a promising prototype for surface decoration of biomedical devices and holds great prospects for clinical translation to enable interventional operations with minimally invasive impacts.
An ingenious yet feasible method of creating a mucosa‐like conformal hydrogel coating, which is soft, lubricative, hydrophilic, antifouling, biocompatible, and stable, is reported. This coating effectively reduces intubation‐related complications. This work represents a breakthrough to endow interventional medical devices with required surface properties, showing promising prospects for clinical translation.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Multistage fracturing of the horizontal well is recognized as the main stimulation technology for shale gas development. The hydraulic fracture geometry and stimulated reservoir volume (SRV) is ...interpreted by using the microseismic mapping technology. In this paper, we used a computerized tomography (CT) scanning technique to reveal the fracture geometry created in natural bedding-developed shale (cubic block of 30 cm × 30 cm × 30 cm) by laboratory fracturing. Experimental results show that partially opened bedding planes are helpful in increasing fracture complexity in shale. However, they tend to dominate fracture patterns for vertical stress difference Δ
σ
v
≤ 6 MPa, which decreases the vertical fracture number, resulting in the minimum SRV. A uniformly distributed complex fracture network requires the induced hydraulic fractures that can connect the pre-existing fractures as well as pulverize the continuum rock mass. In typical shale with a narrow (<0.05 mm) and closed natural fracture system, it is likely to create complex fracture for horizontal stress difference Δ
σ
h
≤ 6 MPa and simple transverse fracture for Δ
σ
h
≥ 9 MPa. However, high naturally fractured shale with a wide open natural fracture system (>0.1 mm) does not agree with the rule that low Δ
σ
h
is favorable for uniformly creating a complex fracture network in zone. In such case, a moderate Δ
σ
h
from 3 to 6 MPa is favorable for both the growth of new hydraulic fractures and the activation of a natural fracture system. Shale bedding, natural fracture, and geostress are objective formation conditions that we cannot change; we can only maximize the fracture complexity by controlling the engineering design for fluid viscosity, flow rate, and well completion type. Variable flow rate fracturing with low-viscosity slickwater fluid of 2.5 mPa s was proved to be an effective treatment to improve the connectivity of induced hydraulic fracture with pre-existing fractures. Moreover, the simultaneous fracturing can effectively reduce the stress difference and increase the fracture number, making it possible to generate a large-scale complex fracture network, even for high Δ
σ
h
from 6 MPa to 12 MPa.
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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
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