Search

Background: Hypoxia-activated prodrugs present new opportunities for safe and effective tumor drug resistance therapy due to their high selectivity for hypoxic cells. However, the uneven distribution of oxygen in solid tumor and insufficient hypoxia in the tumor microenvironment greatly limit its therapeutic efficacy. Results: In this paper, a novel AQ4N-Mn(II)@PDA coordination nanoplatform was designed and functionalized with GMBP1 to target drug-resistant tumor cells. Its excellent photothermal conversion efficiency could achieve local high-temperature photothermal therapy in tumors, which could not only effectively exacerbate tumor hypoxia and thus improve the efficacy of hypoxia-activated chemotherapy of AQ4N but also significantly accelerate Mn2+-mediated Fenton-like activity to enhance chemodynamic therapy. Moreover, real-time monitoring of blood oxygen saturation through photoacoustic imaging could reflect the hypoxic status of tumors during treatment. Furthermore, synergistic treatment effectively inhibited tumor growth and improved the survival rate of mice bearing orthotopic drug-resistant tumors. Conclusions: This study not only provided a new idea for PTT combined with hypoxia-activated chemotherapy and CDT for drug-resistant tumors but also explored a vital theory for real-time monitoring of hypoxia during treatment. [ABSTRACT FROM AUTHOR]

Pentablock terpolymers are potential candidates for the self-assembly of multicompartment nanostructures. In this work, Dissipative Particle Dynamic simulation is employed to investigate how the equilibrium aggregate structures of C3B3A6B3C3 pentablock terpolymers are affected by polymer–solvent interactions in a solution. Multicompartment structures, such as layered micelles, onion-like micelles, onion-like vesicles, unilamellar vesicles, and vesicle-in-vesicle structures, are observed. Vesicles are obtained when the two end C-blocks or the central A-block are hydrophilic. The solvent encapsulation ability and vesicle membrane permeability are assessed. The unilamellar vesicle shows higher encapsulation efficiency and lower membrane permeability compared with the onion-like vesicles. Additionally, the two vesicles show different responses to shear. While the cargo release rate of the onion-like vesicle is not affected by shear, shear results in a slowdown of the release rate for the unilamellar vesicle. The membrane thickness of the unilamellar vesicle can be adjusted using the length of the central A-blocks. Vesicles with thicker membranes hold cargo more effectively. [ABSTRACT FROM AUTHOR]

The study investigates the impact of film thickness on the phase behavior of pentablock terpolymers, denoted as C3B3A6B3C3, when subjected to wall confinement by utilizing the dissipative particle dynamics method. Phase diagrams were constructed to elucidate how factors such as block–block interaction strength, film thickness, and wall properties affect the self-assembly structures. In cases where the wall exhibits no preference for any of the blocks, lamellae phases with orientations perpendicular to the wall are observed. The order–disorder transition (ODT) temperature is found to be influenced by the interaction between the polymer and the wall in thin confinement scenarios. When the wall displays a preference for specific blocks, the orientation of lamellae structures undergoes variations. Lamellae tend to align parallel to the wall when the wall favors A or C blocks, and they orient perpendicularly when B blocks are favored. Furthermore, the mechanical properties of the lamellae structures are related to the conformations of the polymer chains. Structures where chains predominantly adopt a loop conformation exhibit enhanced elastic properties. The ratio of looping to bridging conformations can be adjusted by altering the film thickness and wall selectivity. [ABSTRACT FROM AUTHOR]

In practical engineering, it is common to offset the drainage system axis to avoid conflicts with beams and columns. However, such an offset could significantly affect the system's discharge capacity and drainage safety, leading to a prominent positive pressure above the offset floor. To address this issue, we propose optimizing the system by changing the elbow shapes at the offset position. In our study, we conducted comparative experiments on three elbow shapes, namely, a normal 90° elbow, double 45° elbow, and large curvature elbow, in two experimental systems. Pressure fluctuation and water seal losses were used as experimental parameters to determine the maximum discharge capacity in accordance with the Standard for Capacity Test of Vertical Pipe of the Domestic Residential Drainage System. Our experimental results show that replacing the 90° elbow with the double 45° elbow slightly reduces positive pressure. On the other hand, using the large curvature elbow effectively increases the drainage flow and reduces the positive pressure caused by the upper floor bias. Furthermore, we employed computational fluid dynamics (CFD) software to simulate the flow of water and air in the system, demonstrating the benefits of increasing the elbow at the connecting position. [ABSTRACT FROM AUTHOR]

In this paper, we study the Cauchy problem for the Camassa–Holm equation in Sobolev spaces. Firstly, we establish the energy conservation for weak solutions of the Camassa–Holm equation in H 1 (R) ∩ B 3 , 2 1 (R) and prove that every weak solution in H 7 6 (R) is unique by the embedding H 7 6 (R) ↪ B 3 , 2 1 (R). Then, we obtain the local well-posedness for the Camassa–Holm equation in W 2 , 1 (R). It is worth noting that B 1 , 1 2 (R) ↪ W 2 , 1 (R) and the Camassa–Holm equation is well-posed in B 1 , 1 2 (R) and is ill-posed in W 1 + 1 p , p (R) (1 < p ≤ ∞) by the pervious papers. Our result implies that W 2 , 1 (R) is the critical Sobolev spaces for the well-posedness of the Camassa–Holm equation. [ABSTRACT FROM AUTHOR]

The phase behavior of CBABC pentablock terpolymers confined in thin films is investigated using the Dissipative Particle Dynamic method. Phase diagrams are constructed and used to reveal how chain length ( i -block length), block composition and wall selectivity influence the self-assembly structures. Under neutral walls, four categories of morphologies, i.e., perpendicular lamellae, core–shell types of microstructures, complex networks, and half-domain morphologies, are identified with the change in i -block length. Ordered structures are more common at weak polymer–polymer interaction strengths. For polymers of a consistent chain length, when one of the three components has a relatively smaller length, the morphologies transition is sensitive to block composition. With selective walls, parallel lamellae structures are prevalent. Wall selectivity also impacts chain conformations. While a large portion of chains form loop conformations under A-selective walls, more chains adopt bridge conformation when the wall prefers C-blocks. These findings offer insights for designing nanopatterns using symmetric pentablock terpolymers. [ABSTRACT FROM AUTHOR]

To date, precisely tailoring local active sites of well‐defined earth‐abundant metal‐free carbon‐based electrocatalysts for attractive electrocatalytic oxygen reduction reaction (ORR), remains challenging. Herein, the authors successfully introduce a strain effect on active C–C bonds adjacent to edged graphitic nitrogen (N), which raises appropriate spin‐polarization and charge density of carbon active sites and kinetically favor the facilitation of O2 adsorption and the activation of O‐containing intermediates. Thus, the constructed metal‐free carbon nanoribbons (CNRs‐C) with high‐curved edges exhibit outstanding ORR activity with half‐wave potentials of 0.78 and 0.9 V in 0.5 m H2SO4 and 0.1 m KOH, respectively, overwhelming the planar one (0.52 and 0.81 V) and the N‐doped carbon sheet (0.41 and 0.71 V). Especially in acidic media, the kinetic current density (Jk) is 18 times higher than that of the planar one and the N‐doped carbon sheet. Notably, these findings show the spin polarization of the asymmetric structure by introducing a strain effect on the C–C bonds for boosting ORR. [ABSTRACT FROM AUTHOR]

With the development of health service, animal husbandry, aquaculture and the chemical industry, more and more pollutants are discharged into the water environment, including antibiotics and heavy-metal ions. These hazardous substances pose a great threat to environmental safety and human health. Two new kinds of green solvents, ionic liquids (ILs) and deep eutectic solvents (DESs), are widely utilized in various fields, including separation and environmental engineering, and are attracting much attention from academia and industry. In this study, an optimal ionic liquid and a deep eutectic solvent were selected, and their complex with β-cyclodextrin (β-CD) was first prepared by a process of simple and effective inclusion. After necessary characterization and analysis, two kinds of complexes were applied to prepare a special two-sided sorbent disc by adding a diluent (excipient) and pressing the substance under 5~15 MPa. As a result, the IL and DES were stably immobilized on the disc to play a key role in the selective adsorption of targets. Moreover, the experiments with different hazardous substances achieved the expected results. This study demonstrates that the complex disc, with its easy preparation, good stability, and simple operation, exhibited many merits in its separation performance. We believe it to be a useful tool for water purification and detection of noxious substances. [ABSTRACT FROM AUTHOR]

The transcriptional co‐activator with PDZ‐binding motif (TAZ) is a significant transcription factor downstream of the Hippo pathway regulating organ size, tissue regeneration, cell proliferation and apoptosis. Here, we report on TAZ in response to photoaging mediated by repeated UVA irradiation in skin fibroblasts. Continuous UVA irradiation caused a decrease in TAZ and targeted CTGF mRNA and protein expression in fibroblasts, accompanied by reduced cell proliferation, DNA damage, and cell cycle arrest in G1 phase and S phase reduction. Furthermore, P16 and P21 expression levels were increased, whereas Lamin B1 and Lamin A/C expression were decreased as a result of repeated UVA exposure. We further demonstrated that TAZ reduction enables photoaging caused by continuously UVA‐irradiated fibroblasts. TAZ overexpression decreases G1 phase, augments the S phase and reduces P16 and P21 protein expression levels in fibroblasts. However, TAZ overexpressing cells exposed to chronic‐UVA radiation show induced G1 phase arrest, an S phase reduction, and elevated P16 and P21 protein levels in fibroblasts, compared with TAZ overexpression cells. These findings suggest a novel function of TAZ to reduce photoaging in fibroblasts. This regulation implies that TAZ might be a viable therapeutic target for photoaging or UVA‐related skin disorders. [ABSTRACT FROM AUTHOR]

Covalent organic nanosheets (CONs) are receiving tremendous interest for their potential in versatile applications. However, the synthesis of CONs usually suffers from the use of toxic solvents, low yields and uncontrollable thickness. Here, we report a green, high yield, and scalable strategy to strip two-dimensional imine-linked covalent organic framework (COF) powders in water using bi-functional ionic liquids as both the intercalator and stabilizer under ambient conditions. It is shown that the exfoliation yield reaches up to 66.6%, which is a record value for the delamination of CONs from bulk COF powder. The thickness of CONs is mainly in the range from 0.4 to 2.0 nm and the lateral size is large up to a few hundred nanometers. Importantly, the aqueous IL solutions can be reused and recycled for the exfoliation of CONs. The acid–base and hydrogen bond interactions between CONs and cations of the ILs are found to play critical roles in the delamination and stability of CONs. Furthermore, the CONs without any additives such as metals, photosensitizers, and sacrificial agents have been used as catalysts for photocatalytic CO2 reduction with gaseous water to yield CO in the gas phase under visible-light irradiation. The production rate of CO is 132.2 μmol g−1 h−1, which is twice that by the bulk COF powder, and outperforms most visible-light driven metal-free COFs reported so far. Therefore, the liquid phase stripping approach reported here possesses tremendous potentiality in mass production of CONs for high efficiency photocatalysis of CO2 reduction in the gas phase. [ABSTRACT FROM AUTHOR]

Wine contains a multitude of volatile and non-volatile compounds. The sensory characteristics of wine are strongly influenced by the volatile aromas. In this study, we used headspace solid-phase micro-extraction (HS-SPME) and gas chromatography mass spectrometry (GC–MS) to analyze the Cabernet Sauvignon Grape samples obtained from Ningxia (China) processed by drying, winemaking, and aging, respectively. Thirty-seven compounds that significantly influenced the wine aroma characteristics were analyzed quantitatively. Results showed a close correlation of grape or wine volatile components with the flavor characteristics. 16, 29, and 32 aroma compounds were characterized during the drying, fermentation, and aging processes, respectively. Drying of Cabernet Sauvignon decreased fruity aromas but enhanced herbaceous and caramel aromas. After fermentation, the aroma component showed substantial increase, with more pronounced caramel, floral, and fruity characteristics in the wine. The aging process decreased the aroma content, but there appeared to be a positive influence on the formation of aging aromas, such as furfuryl alcohol, furfural, and 5-methylfurfural. The aging process not only directly altered the general composition of wine, but also showed a positive influence on sensory properties. These findings shed new light on the mechanism of wine drying, fermentation, and aging process, which can help improve wine characteristics. [ABSTRACT FROM AUTHOR]

Developing renewable energy (RE) is necessary for economic growth and sustainable development. Policy support provides a source of motivation for developing RE. Thus, after analyzing the evolution of China's RE policy, we establish a Two-way fixed effects model using the data of 30 Chinese provinces during the period 2011–2018. We explored the differences in the impacts of five different types of RE policies on provincial RE development in China. Furthermore, we explored the influencing mechanism and heterogeneity of between different policies and RE development. Results show that: 1) technology development policies can promote RE development by creating an innovation effect while the effect worsens during 2015–2018. 2) the increase in market management policies can inhibit RE development, especially for the provinces with rich RE resources. and 3) the number of comprehensive planning policies and industrial management policies as well as polices' number of electricity price regulation, finance, and tax support have no significant effects on RE development in the total sample. To further achieve the high-quality development of RE, the Chinese government needs to control the number of policies in the market management but enhance the execution and supervision of planning management for provinces with poor RE resources. [ABSTRACT FROM AUTHOR]

The lack of highly efficient, inexpensive catalysts severely hinders the large‐scale application of electrochemical energy conversion technologies (e.g., electrochemical hydrogen evolution reaction (HER) for hydrogen production, metal–air batteries (Cathode: oxygen reduction reaction (ORR))). As a new class of nanomaterials with a high ratio of surface atoms and tunable composition and electronic structure, metal nanocluster (NCs) are promising candidates as catalysts. Herein, a novel catalyst using S,N‐doped carbon matrix (NSCSs) is synthesized to efficiently stabilize high density and ultra‐uniform ruthenium (Ru) nanoclusters (Ru@NSCSs) by small‐molecule self‐assembly pyrolysis approach. The obtained Ru@NSCSs catalyst exhibits outstanding HER activity in all pH conditions (especially with a low overpotential of 5 mV at a current density of 10 mA cm−2 in 1 m KOH) and excellent ORR performance (half‐wave potential (E1/2) of 0.854 V in 0.1 m KOH). Based on the experimental investigations and theoretical calculations, it is discovered that the S‐atom can modulate the electronic structure and optimization of redox states on the surficial sites of Ru NCs during the ORR process. This work provides a feasible strategy for understanding and regulating the metal–support interface of ultra‐uniform nanoclusters catalysts. [ABSTRACT FROM AUTHOR]

For the famous Camassa-Holm equation, the well-posedness in B p , 1 1 + 1 p (R) with p ∈ [ 1 , ∞) and the ill-posedness in B p , r 1 + 1 p (R) with p ∈ [ 1 , ∞ ] , r ∈ (1 , ∞ ] had been studied in [13,14,16,23] , that is to say, it only left an open problem in the critical case B ∞ , 1 1 (R) proposed by Danchin in [13,14]. In this paper, we solve this problem by proving the norm inflation and hence the ill-posedness for the Camassa-Holm equation in B ∞ , 1 1 (R). Therefore, the well-posedness and ill-posedness for the Camassa-Holm equation in all critical Besov spaces B p , 1 1 + 1 p (R) with p ∈ [ 1 , ∞ ] have been completed. Finally, since the norm inflation occurs by choosing an special initial data u 0 ∈ B ∞ , 1 1 (R) but u 0 x 2 ∉ B ∞ , 1 0 (R) (an example implies B ∞ , 1 0 (R) is not a Banach algebra), we then prove that this condition is necessary. That is, if u 0 x 2 ∈ B ∞ , 1 0 (R) holds, then the Camassa-Holm equation has a unique solution u (t , x) ∈ C T (B ∞ , 1 1 (R)) ∩ C T 1 (B ∞ , 1 0 (R)) and the norm inflation will not occur. [ABSTRACT FROM AUTHOR]

L-Cysteine and L-methionine, as the only two sulfur-containing amino acids among the canonical 20 amino acids, possess distinct characteristics and find wide-ranging industrial applications. The use of different organisms for fermentative production of L-cysteine and L-methionine is gaining increasing attention, with Escherichia coli being extensively studied as the preferred strain. This preference is due to its ability to grow rapidly in cost-effective media, its robustness for industrial processes, the well-characterized metabolism, and the availability of molecular tools for genetic engineering. This review focuses on the genetic and molecular mechanisms involved in the production of these sulfur-containing amino acids in E. coli. Additionally, we systematically summarize the metabolic engineering strategies employed to enhance their production, including the identification of new targets, modulation of metabolic fluxes, modification of transport systems, dynamic regulation strategies, and optimization of fermentation conditions. The strategies and design principles discussed in this review hold the potential to facilitate the development of strain and process engineering for direct fermentation of sulfur-containing amino acids. [ABSTRACT FROM AUTHOR]

Fe single-atom catalysts (SACs) have emerged as a promising alternative to platinum for catalyzing oxygen reduction reactions (ORR). Nevertheless, their practical applicability is hindered by insufficient stability caused by structural corrosion during ORR. Here, we developed an effective strategy to optimize and stabilize the Fe SAs (single-atoms) sites by implanting chromium (Cr) atomic clusters (ACs) to address the formidable deactivation issue of the best-performing yet unstable Fe-N-C catalysts. Cr AC -Fe 1 /N-S-C demonstrates an amazing stability with a negligible decline in activity after 100,000 CV cycles, and can maintain 81% of initial current after a continuous 50-hour operation period. Theoretical calculations and experimental evidence substantiate that the integration of Cr ACs not only weakens the binding of OH* to the Fe site, thereby facilitating the ORR process, but also eliminates in situ-generated reactive oxygen species (ROS) and retards Fe ion leaching from active sites, thus stabilizing of the Fe SA sites. [Display omitted] • A novel Cr ACs-modified Fe SAs co-embedded on N, S co-doped carbon matrix is prepared by one-step pyrolysis. • Cr AC sites act proactively to eliminate in situ-generated radicals and show down Fe leaching at the neighboring Fe sites. • The sample exhibits highly stable ORR performance and can be run over 500 hours continuously in a zinc-air battery. [ABSTRACT FROM AUTHOR]

To better understand the shear stress distribution in rock-cemented discontinuities, such as bedding planes and mineral-filled natural fractures (NFs), subjected to direct shear, an analytical solution for shear stress was first derived on the basis of the compression and bending theories of materials. The shear stresses obtained using the analytical solution for different conditions were then verified by the numerical simulation method. Finally, the main factors that influence the shear stress distribution in cemented discontinuities were explored using the analytical solution and numerical simulation methods. The results showed that the internal moment generated by shear forces significantly affects the shear stress distribution in a cemented NF. The analytical solution which considers the internal moment can accurately predict the shear stress distribution in most cases. The shear and normal stresses are both concentrated near the ends of cemented NF; however, they are comparatively uniform in the central portion. The shear stress concentration decreases with the increasing width of cemented NF, whereas it increases with Young's modulus of cemented NF. The nonuniformity in shear stress decreases with the specimen height, and only when the specimen height is equal to the specimen length, the error produced by the analytical solution attains a minimum. The tractions on the loading surfaces are significantly nonuniform, and the nonuniform tractions are to balance the bending moment created by shear forces. Moreover, the shear box can dramatically influence the shear stress distribution in cemented NF. Uniform normal and shear displacements which represent the normal and shear forces loaded via a rigid shear box should be used for the boundary conditions. The findings in this study can provide a theoretical foundation for the evaluation of deformation properties and shear strength of intact rocks, rock interfaces, bedding planes, or mineral-filled NFs subjected to direct shear. [ABSTRACT FROM AUTHOR]

Cryopreservation of single seminiferous tubule is significant for fertility preservation, especially for male patients with cryptorchidism, Y-chromosome deletion and orchitis. However, there are few studies on cryopreservation of single seminiferous tubule. This study proposes several improved strategies for cryopreservation of single seminiferous tubule in mice. First, single seminiferous tubule was cryopreserved with modified slow freezing and vitrification methods. The results showed that the apoptosis negative rates of spermatogenic cells in single seminiferous tubule with modified slow freezing method were significantly higher than vitrification with plastic slide. Then, plastic slide and two metal vitrification carriers with high thermal conductivity, copper mesh and aluminum foil, were used to vitrify single seminiferous tubule. The metal carriers could improve the outcome of vitrification than plastic slide. The apoptosis negative rates of spermatogenic cells in the aluminum foil group was significantly higher than that in the copper mesh group. Finally, single seminiferous tubule was perfused with CPAs by micro-injection technique and vitrified. The results of cryo-microscopy experiments showed that the ice crystals formed inside the injected seminiferous tubule was reduced during the cooling process, the apoptosis negative rate of spermatocytes, spermatids and Sertoli cells were significantly higher than that of the non-injection group, indicating that the injection technique can effectively improve the effect of vitrification. This study has potential clinical value for in-vitro culture of spermatogonial stem cells and autologous testicular tissue grafting in patients with azoospermia. [ABSTRACT FROM AUTHOR]

We prove that the initial value problem for the Euler–Poincaré equations is not locally well-posed for initial data in the Besov space B p , ∞ σ whenever σ > 2 + max { 1 + d p , 3 2 }. By presenting a new construction of initial data u 0 , we prove the corresponding solution of Euler–Poincaré equations starting from u 0 is discontinuous at t = 0 in the norm of B p , ∞ σ , which implies the ill-posedness. Since this problem is locally well-posed in the Besov space B p , r σ for r < ∞ and the same σ , our result suggests that well-posedness does not hold at the endpoint r = ∞. [ABSTRACT FROM AUTHOR]

A novel colorimetric and fluorescence dual-mode sensing system based on UCNPs for the detection of XA is proposed by combining the IFE and the cyclic signal amplification strategy. The proposed assay was applied to the determination of XA in serum samples and the recovery rates of the spiked samples were in the range of 96.3–104.3%, indicating the proposed assay could be adapted for rapid sensitive detection of XA in real samples. [Display omitted] • A highly sensitive dual-mode sensor platform for detecting XA was constructed. • The high sensitivity and selectivity could be achieved by cycle signal amplification strategy. • The fluorescent and colorimetric dual readout signal make the analysis results convincing. • The linear detection range of XA was 2.5–150 μM with LOD of 0.58 μM. Up-conversion nanoparticles (UCNPs), especially single-band bright red UCNPs, have better penetration of biological tissues, absorb less lost energy, and have higher sensitivity and accuracy in the determination of actual biological samples in the field of biosensing. Here, a novel colorimetric and fluorescent dual-channel method based upon an internal filtration effect (IFE) quenching mechanism was proposed for the quantitative analysis of xanthine (XA) by using red UCNPs as fluorescence indicator and 3,3′,5,5′ -tetramethylbenzidine (TMB) as chromogenic substrate. The sensitivity of the detection system was also enhanced by a cycle signal amplification strategy based on the Fenton reaction. Under the best conditions, the detection limits of XA by fluorescent and colorimetric methods were 0.58 μM and 1.19 μM, respectively. The developed method was applied to the detection of XA in actual serum samples, and the recoveries of the spiked samples by fluorescent and colorimetric methods were in the range of 96.3–104.3 % and 94.3–105.4 %, respectively. In addition, the commercial ELISA method was used to verify the application of the proposed method and the test results of XA were close to those obtained by fluorescent and colorimetric methods, indicating that the accuracy of the developed nanosensing system was acceptable. [ABSTRACT FROM AUTHOR]

Obtaining the vertical distribution profile of trace gas is of great significance for studying the diffusion procedure of air pollution. In this article, a look-up table method based on multi-axis differential optical absorption spectroscopy (MAXDOAS) technology is established for retrieving the tropospheric NO2 vertical distribution profiles. This method retrieves the aerosol extinction profiles with minimum cost function. Then, the aerosol extinction profiles and the atmospheric radiation transfer model (RTM) are employed to establish the look-up table for retrieving the NO2 vertical column densities (VCDs) and profiles. The measured NO2 differential slant column densities (DSCDs) are compared with the NO2 DSCDs simulated by the atmospheric RTM, and the NO2 VCDs, the weight factor of NO2 in the boundary layer, and the boundary layer height are obtained by the minimization process. The look-up table is established to retrieve NO2 VCDs based on MAX-DOAS measurements in Huaibei area, and the results are compared with the data from Copernicus Atmospheric Monitoring Service(CAMS) model. It isfound that there are nearly consistent and the correlation coefficient R2 is morethan 0.86. The results show that this technology provides a more convenient and accurate retrieval method for the stereoscopic monitoring of atmospheric environment. [ABSTRACT FROM AUTHOR]

Net-stacked hierarchical CdOHF architectures were controllably synthesized via a simple hydrothermal method. The SEM and TEM results show that the hierarchical CdOHF structure is made up of many CdOHF nanobelts. Different pH values and reaction times make the CdOHF feature adjustable structural variations with 1D nanobelts, nanobelt-woven 2D nets and net-stacked 3D hierarchical structures. With a first-order reaction rate constant that was 5 times higher than those of other CdOHF morphologies, the obtained net-stacked hierarchical CdOHF architectures exhibited high efficiency and selectivity for degrading the cationic dye malachite green (MG) under visible light irradiation, for example, the decolorization rate for MG (40 mg L−1) solution reached approximately 100% within 30 min. Moreover, the hierarchical CdOHF also displayed good photochemical stability for the degradation of MG after five recycles. The improved photocatalytic efficiency of the 3D net-stacked hierarchical CdOHF is ascribed to the synergistic effects of the porous hierarchical architectures, narrower band gap energy and large BET surface areas. This work provides a simple and feasible strategy for controllable synthesis of 3D hierarchical micro/nanomaterials with high performance, and such inexpensive high-performance hierarchical CdOHF architectures can find potential applications for the degradation of organic dyes. [ABSTRACT FROM AUTHOR]

Poria cocos polysaccharides (PCPs) are of high research value because of their important biological functions. However, the ways to extract a PCP are limited and its yield is relatively low in current reports. In this study, a new ternary deep eutectic solvent (DES) composed of choline chloride, 1,3-butanediol and D -sorbitol was used to efficiently extract bioactive polysaccharides from poria cocos assisted by the new tool of far infrared radiation (FIR) together with hot air circulation (HAC). The yield of a polysaccharide (PCP-DL) obtained by this new method was 55.02 ± 0.87% under the optimized conditions of sieving mesh (300 mesh), liquid–solid ratio (30 mL g−1), intensity of FIR (300 W m−2), and circulated air temperature (80 °C). Meanwhile, the extraction mechanism of PCP-DL was investigated by comprehensive characterization studies and extraction kinetics. The recovered DES still retained its performance after recycling five times by dialysis. A laboratory-scale life cycle assessment (LCA) was applied to analyze the potential environmental profiles and the results showed that this new extraction process possessed environmental impact reductions of 93.61% waste solids and 69.72% fossil fuel depletion potential in contrast to the traditional method. Furthermore, chromatographic and spectral analyses were used to analyze the product and confirm the presence of α-,β-pyranose, as well as five kinds of glycosidic linkages, in target polysaccharides with a molecular weight (Mw) of 2.05 × 104 Da. Scanning electron microscopy (SEM) revealed that it was an amorphous aggregate with an irregular spherical shape and loose porous surface. Finally, the product exhibited a similar inhibitory activity to that of donepezil against acetylcholinesterase (AChE, 73.82 ± 0.60%) and butyrylcholinesterase (BChE, 63.85 ± 0.54%) at 500 μg mL−1 as a mixed-type competitive inhibitor for these enzymes. The interaction sites between AChE and the fragment of PCP-DL were simulated by molecular docking, which provided a theoretical basis for the above inhibition assays. [ABSTRACT FROM AUTHOR]

In this paper, we first establish the local well-posedness and the rotational speed limit for the rotation Camassa–Holm equation modelling the equatorial water waves with the weak Coriolis effect in nonhomogeneous Besov spaces B p , r s with s > max (1 + 1 p , 3 2) or s = 1 + 1 p , r = 1. Then, we prove the local ill-posedness of the rotation Camassa–Holm equation in B p , r 1 + 1 p , p ∈ [ 1 , + ∞ ] , r ∈ (1 , + ∞ ]. Finally, we show the existence of global weak solutions for the rotation Camassa–Holm equation. [ABSTRACT FROM AUTHOR]

The mammalian orthoreovirus double-stranded (ds) RNA-binding protein σ3 is a multifunctional protein that promotes viral protein synthesis and facilitates viral entry and assembly. The dsRNA-binding capacity of σ3 correlates with its capacity to prevent dsRNA-mediated activation of protein kinase R (PKR). However, the effect of σ3 binding to dsRNA during viral infection is largely unknown. To identify functions of σ3 dsRNA-binding activity during reovirus infection, we engineered a panel of thirteen σ3 mutants and screened them for the capacity to bind dsRNA. Six mutants were defective in dsRNA binding, and mutations in these constructs cluster in a putative dsRNA-binding region on the surface of σ3. Two recombinant viruses expressing these σ3 dsRNA-binding mutants, K287T and R296T, display strikingly different phenotypes. In a cell-type dependent manner, K287T, but not R296T, replicates less efficiently than wild-type (WT) virus. In cells in which K287T virus demonstrates a replication deficit, PKR activation occurs and abundant stress granules (SGs) are formed at late times post-infection. In contrast, the R296T virus retains the capacity to suppress activation of PKR and does not mediate formation of SGs at late times post-infection. These findings indicate that σ3 inhibits PKR independently of its capacity to bind dsRNA. In infected mice, K287T produces lower viral titers in the spleen, liver, lungs, and heart relative to WT or R296T. Moreover, mice inoculated with WT or R296T viruses develop myocarditis, whereas those inoculated with K287T do not. Overall, our results indicate that σ3 functions to suppress PKR activation and subsequent SG formation during viral infection and that these functions correlate with virulence in mice. Author summary: The σ3 protein of mammalian orthoreoviruses is a double-stranded RNA binding protein that has classically been thought to function by scavenging dsRNA within infected cells and thus prevents activation of cellular sensors of dsRNA such as the kinase PKR. Here we used mutagenesis to identify the region of σ3 responsible for binding dsRNA. Characterization of mutant viruses expressing σ3 proteins incapable of binding dsRNA show that contrary to expectation, dsRNA binding is not required for σ3-mediated inhibition of PKR. We show that one mutant virus (R296T) despite being deficient in dsRNA-binding can inhibit PKR and replicates similar to WT virus. In contrast, another mutant virus (K287T) that bears a σ3 protein that cannot prevent dsRNA-mediated activation of PKR induces stress granules in infected cells and replicates less efficiently than WT virus. In vivo, the K287T mutant is attenuated in its replication and unlike WT virus and the R296T mutant virus does not cause heart disease (myocarditis). [ABSTRACT FROM AUTHOR]

RuO2 has been considered as the most likely acidic oxygen evolution reaction (OER) catalyst to replace IrO2, but its performance, especially long‐term stability under harsh acidic conditions, is still unacceptable. Here, we propose a grain boundary (GB) engineering strategy by fabricating the ultrathin porous RuO2 nanosheet with abundant of grain boundaries (GB‐RuO2) as an efficient acid OER catalyst. The involvement of GB induces significant tensile stress and creates an unsaturated coordination environment, effectively optimizing the adsorption of intermediates and stabilizing active site structure during OER process. Notably, the GB‐RuO2 not only exhibits a low overpotential (η10=187 mV) with an ultra‐low Tafel slope (34.5 mV dec−1), but also steadily operates for over 550 h in 0.1 M HClO4. Quasi in situ/operando methods confirm that the improved stability is attributed to GB preventing Ru dissolution and greatly inhibiting the lattice oxygen oxidation mechanism (LOM). A proton exchange membrane water electrolysis (PEMWE) using the GB‐RuO2 catalyst operates a low voltage of 1.669 V at 2 A cm−2 and operates stably for 100 h at 100 mA cm−2. [ABSTRACT FROM AUTHOR]

RuO2 has been considered as the most likely acidic oxygen evolution reaction (OER) catalyst to replace IrO2, but its performance, especially long‐term stability under harsh acidic conditions, is still unacceptable. Here, we propose a grain boundary (GB) engineering strategy by fabricating the ultrathin porous RuO2 nanosheet with abundant of grain boundaries (GB‐RuO2) as an efficient acid OER catalyst. The involvement of GB induces significant tensile stress and creates an unsaturated coordination environment, effectively optimizing the adsorption of intermediates and stabilizing active site structure during OER process. Notably, the GB‐RuO2 not only exhibits a low overpotential (η10=187 mV) with an ultra‐low Tafel slope (34.5 mV dec−1), but also steadily operates for over 550 h in 0.1 M HClO4. Quasi in situ/operando methods confirm that the improved stability is attributed to GB preventing Ru dissolution and greatly inhibiting the lattice oxygen oxidation mechanism (LOM). A proton exchange membrane water electrolysis (PEMWE) using the GB‐RuO2 catalyst operates a low voltage of 1.669 V at 2 A cm−2 and operates stably for 100 h at 100 mA cm−2. [ABSTRACT FROM AUTHOR]

Seaweed, or macroalgae has traditionally been part of Asian cuisine for decades and is also becoming increasingly popular as a food source in Europe and other Western countries. However, seaweed can accumulate elements from the environment and consequently may be a source of exposure to toxic elements, or potentially harmful levels of micronutrients. Food safety issues related to the use of seaweed as food and animal feed are very important given the increased use of such products. Current standards, regulations and recommendations regarding heavy metals (cadmium, lead and mercury), arsenic and iodine in seaweed food and feed products in China and Europe are included in this review. Furthermore, the levels of these elements in different seaweed products, dietary exposure, and risk management measures for seaweed products are also discussed. The chemical hazards of particular concern in seaweeds are iodine, inorganic arsenic and cadmium depending on seaweed species, consumption and processing or preparation methods. In the absence of harmonized international standards or guidelines that specifically address food safety of seaweed production, processing and utilization, there are considerable differences in the regulations and standards concerning inorganic contaminants and iodine among different countries. This comprehensive review identifies knowledge gaps and provides a scientific basis for further work regarding developing unified food safety legislation, standards or guidelines related to seaweed products. • Seaweed is a sustainable food source worldwide. • The potential food safety issues of particular concern in seaweeds are iodine, inorganic arsenic and cadmium. • Different MLs for arsenic, lead, cadmium, mercury and UL for iodine in seaweeds are established in national regulations. • There are currently no harmonized international standards for seaweed safety due to scarcity of occurrence and intakedata. [ABSTRACT FROM AUTHOR]

Adsorbents with high effective adsorption capabilities have attracted extensive interest and are promising for the removal of heavy metal ions from wastewater. Herein, we prepared well-dispersed ZnOHF microspheres with efficient adsorptive removal toward Pb2+ in an aqueous environment via an amino acid assisted hydrothermal method. The obtained microspheres were self-assembled by numerous nanotubes with an outer diameter of ∼10 nm and a wall thickness of about 3.5 nm. By taking advantage of the large specific surface areas of nanotube-assembled microspheres (271.06 m2 g−1), the maximum adsorption capacity for Pb2+ was up to 285.7 mg g−1 in solution. Further analysis revealed the key role of the geometry structure of fine nanotube-assembled microspheres in boosting their adsorption ability. Furthermore, we proposed a potential growth mechanism of the as-prepared microspheres. The thermodynamic study of Pb2+ adsorbed on nanotube-assembled ZnOHF microspheres suggests that it is an endothermic and spontaneous process. This finding may open a new avenue to design efficient sorbents with high surface areas and effective heavy metal or organic dye removal ability in solution. [ABSTRACT FROM AUTHOR]

Induction of necroptosis by mammalian reovirus requires both type I interferon (IFN)-signaling and viral replication events that lead to production of progeny genomic double-stranded RNA (dsRNA). The reovirus outer capsid protein μ1 negatively regulates reovirus-induced necroptosis by limiting RNA synthesis. To determine if the outer capsid protein σ3, which interacts with μ1, also functions in regulating necroptosis, we used small interfering RNA (siRNA)-mediated knockdown. Similarly to what was observed in diminishment of μ1 expression, knockdown of newly synthesized σ3 enhances necroptosis. Knockdown of σ3 does not impact reovirus RNA synthesis. Instead, this increase in necroptosis following σ3 knockdown is accompanied by an increase in IFN production. Furthermore, ectopic expression of σ3 is sufficient to block IFN expression following infection. Surprisingly, the capacity of σ3 protein to bind dsRNA does not impact its capacity to diminish production of IFN. Consistent with this, infection with a virus harboring a mutation in the dsRNA binding domain of σ3 does not result in enhanced production of IFN or necroptosis. Together, these data suggest that σ3 limits the production of IFN to control innate immune signaling and necroptosis following infection through a mechanism that is independent of its dsRNA binding capacity. [ABSTRACT FROM AUTHOR]

Cardiac hypertrophy is a major risk factor for congestive heart failure, a leading cause of morbidity and mortality. Abrogating hypertrophic progression is a well-recognized therapeutic goal. Mitochondrial dysfunction is a hallmark of numerous human diseases, including cardiac hypertrophy and heart failure. F1Fo-ATP synthase catalyzes the final step of oxidative energy production in mitochondria. Oligomycin sensitivity conferring protein (OSCP), a key component of the F1Fo-ATP synthase, plays an essential role in mitochondrial energy metabolism. However, the effects of OSCP-targeted therapy on cardiac hypertrophy remain unknown. In the present study, we found that impaired cardiac expression of OSCP is concomitant with mitochondrial dysfunction in the hypertrophied heart. We used cardiac-specific, adeno-associated virus-mediated gene therapy of OSCP to treat mice subjected to pressure overload induced by transverse aortic constriction (TAC). OSCP gene therapy protected the TAC-mice from cardiac dysfunction, cardiomyocyte hypertrophy, and fibrosis. OSCP gene therapy also enhanced mitochondrial respiration capacities in TAC-mice. Consistently, OSCP gene therapy attenuated reactive oxygen species and opening of mitochondrial permeability transition pore in the hypertrophied heart. Together, adeno-associated virus type 9-mediated, cardiac-specific OSCP overexpression can protect the heart via improving mitochondrial function. This result may provide insights into a novel therapy for cardiac hypertrophy and heart failure. [ABSTRACT FROM AUTHOR]

The current study was performed to evaluate the possible protective effects of fucoidan (F) and sodium alginate (SA) against lead-induced oxidative damage in vivo , and to identify relevant underlying mechanisms. Health Sprague Dawley (SD) rats were divided into nine groups of ten rats each and treated orally with lead acetate (5 mg/kg, Pb2+) for 4 weeks, then gavaged with DMSA (Meso-2, 3-dimercaptosuccinic acid, 25 mg/kg), F (50, 100, 200 mg/kg) and SA (50, 100, 200 mg/kg) individually after successful modelling. We found that the administration of both F or SA resulted in a beneficial effect by significantly decreasing lead levels (p < 0.05) in the kidneys from 2.85 mg/kg to 0.79 mg/kg and improving antioxidant status (SOD, GSH, and CAT) thereby alleviating lead-induced damage and injury of the liver and kidneys (AST, BUN, and Cr). Both natural extracts exerted dose-dependent effects. Protective effects were further demonstrated by histopathology. Our results demonstrate that the F and SA are effective natural extracts for lead-eliminating, and that they can ameliorate oxidative damage induced by lead toxicity. • Effects of fucoidan (F) and sodium alginate (SA) on lead-induced oxidative damage studied • Administration of F and SA alleviated lead-induced oxidative damage. • Administration of F and SA ameliorated diminished liver and kidney function. • F and SA are promising antioxidants against lead-induced oxidative stress in rats. [ABSTRACT FROM AUTHOR]

As an eco‐friendly construction material, magnesium oxychloride cement (MOC) has attracted much research interest in recent decades, however, its mechanical properties degrade severely under water attack, which has prevented its wide application in engineering structures. As a widely used mineral waste, fly ash has been applied in civil engineering for decades. The active SiO2 in fly ash is considered to be conductive to improve the water resistance of MOC. In this paper, the influence of fly ash on the mechanical properties of MOC is investigated, especially when subject to water attack. First, the basic mix design of the MOC with a suitable combination of the molar ratios of MgO/MgCl2 and H2O/MgCl2 is developed, and the developed basic MOC mix is modified by adding fly ash to improve its water resistance. Second, the physical and mechanical properties of both the basic MOC and the fly ash modified MOC, such as compressive strength, Young's modulus, flexural strength cured at room temperature, and immersed in water for 28 days at room temperature (25°C) are determined. It is found that the incorporation of fly ash decreases the workability or fluidity, retards the setting time, but improves the compressive strength and water resistance of the MOC. The techniques of X‐ray diffraction, Fourier transform infrared spectroscopy, thermogravimetric analysis/differential scanning calorimetry, scanning electron microscopy, and mercury intrusion porosimetry are applied to the MOC specimens to discover the mechanism by which fly ash affects on the water resistance of MOC. The microscale analysis shows that the addition of fly ash optimizes the pore distribution in MOC resulting in a denser structure, which contributes to the water repellence. [ABSTRACT FROM AUTHOR]

Oocyte cryopreservation is an important technology in assisted reproduction and fertility preservation. However, the developmental potential of cryopreserved oocyte remains poor. Osmotic stress injury (OSI) during cryoprotectants (CPAs) loading and unloading steps has critical impact on successful cryopreservation. In order to minimize OSI to oocytes, a microfluidic device was designed and fabricated to achieve continuous CPA concentration change. MII porcine oocytes were loaded and unloaded CPAs with step-wise and microfluidic methods, oocyte volume changes were recorded and compared, loading and unloading duration of microfluidic methods were optimized. The survival and developmental rate of treated oocytes in step-wise and microfluidic linear methods were also evaluated. The results showed that oocyte volume changes with microfluidic method were obviously less than step-wise method, and the survival, cleavage and blastocyst rate of oocytes were 95.3%, 64.4%, and 19.4%, respectively, which were significantly higher than the traditional step-wise method (79.4%, 43.6%, and 9.7%) (p < 0.05). In conclusion, microfluidic device can effectively reduce the osmotic damage to oocytes and improve the survival rate and developmental rate of oocytes, which may provide a new path for oocyte cryopreservation. [ABSTRACT FROM AUTHOR]

The occurrence of cracking, loosening, and other distresses in asphalt pavements is closely related to the failure of asphalt–aggregate adhesion. Studying the effect of asphalt film thickness on asphalt–aggregate adhesion can facilitate an understanding of the mechanism of disease in asphalt pavements. To study the impact of asphalt film thickness on asphalt–aggregate adhesion, this study tested and evaluated the adhesion between asphalt and aggregates at different asphalt film thicknesses from a macromechanical perspective via pullout tests. In addition, based on the surface energy theory, the effects of different film thicknesses on the adhesion of asphalt–aggregate were analyzed from a surface mechanics perspective. Further, the aggregates were subjected to surface property testing to further investigate the differences between the surface mechanics and the macromechanics results. The results showed that for an asphalt film thickness of 400 μm, the failure energy density (FED) and cohesive work (WA) of the asphalt exhibited the same trend, and certain properties of asphalt influenced its adhesion to the aggregate. For an asphalt film thickness of 25 μm, the FED and the asphalt adhesion work (Was) exhibited the same trend, and the combined effect of the asphalt and slag properties influenced the adhesion of asphalt to steel slag. Moreover, with decreasing asphalt film thickness, the adhesion between asphalt and aggregates was reduced owing to the influencing factors of the asphalt, which can effectively reduce the influence of the aging effect on adhesion. [ABSTRACT FROM AUTHOR]

TMB was oxidized by Ag+ to TMBox quenching the fluorescence of the ligand-free UCNPs based upon the IFE principle. However, when in the presence of ALP and AAP, ALP could catalyze the hydrolysis of AAP to produce AA. The generated AA could inhibit TMBox production at both ends of the reversible process resulting in the fluorescent recovery of ligand-free UCNP and the detection ALP signal is amplified through this cascade process. Based on this principle, the cascade signal amplification strategy mediated by AA is constructed. [Display omitted] • A fluorescent and colorimetric detection of ALP based on ligand-free UCNPs was proposed. • The high sensitivity of the detection system is achieved by ECSAm. • The fluorescent quenching mechanism of UCNPs by TMBox based on IFE is flexible. • The assay based on the reversible oxidation of TMB can be extended to detect more analytes. • LOD of the sensor s for ALP is 0.032 U/L, which is lower than that of some reported literatures. An upconversion signal readout platform for the detection of alkaline phosphatase (ALP) was constructed by combining the inner filter effect (IFE) and the cascade signal amplification strategy. First, 3, 3′, 5, 5′ -tetramethylbenzidine (TMB) is oxidized by Ag+ to the oxidative product (TMBox), which quenches the up-conversion luminescence (UCL) of the ligand-free up-conversion nanoparticles (UCNPs) through the IFE principle. However, when in the presence of ascorbic acid 2-phosphate (AAP) and ALP, AAP is catalytically hydrolyzed by ALP to produce ascorbic acid (AA), which could not only decrease TMBox formation by reducing Ag+, but also reduce the TMBox generated to TMB, thereby resulting in fluorescence recovery of UCNP. Under optimal experimental conditions, ALP was linearly correlated in the range of 0.15∼8 U/L with a LOD of 0.032 U/L (S/N=3). In addition, the developed method was applied to the detection of ALP in actual serum samples, and the detection result was close to that of the traditional pNPP-based standard assay, which showed that the UCNP-TMB nanosystem has great potential to accurately detect ALP in the clinical bioassay. [ABSTRACT FROM AUTHOR]

[Display omitted] • Aqueous solution of quaternary ammonium hydroxide is used to exfoliate MONs from bulk MOF powder. • The exfoliation yield of MONs is high up to 27.5%. • The MONs is mainly in the range from 1 to 3 layers. • The basicity and molecular size of quaternary ammonium hydroxide play vital roles in exfoliation. • The CO production rate catalyzed by MON is 118.7 μmol g−1 h−1 and the selectivity for CO is ca.100%. Metal−organic framework nanosheets (MONs) show promising applications in many fields, but the production of large amounts of high-quality MONs remains a challenge. Here, we report a general liquid-phase stripped approach to exfoliate a benzoic acid linked MOF (Al 2 (OH) 2 TCPP-Co) in water by using quaternary ammonium hydroxides as deprotonation reagent, intercalator and stabilizer simultaneously. It is shown that the stripped yield is high up to 27.5%, the thickness of MONs is mainly 1–3 nm, and the horizontal size is less than one hundred nanometers. The molecular geometry and alkalinity of quaternary ammonium hydroxides play vital roles in the exfoliation of MONs. Moreover, the MONs have been applied as photocatalysts for the conversion of CO 2 to CO in a gas–solid model under UV–visible light illumination without using any photosensitizer and sacrificial agents. The productivity rate of CO is 118.7 μmol g−1 h−1, which outperforms most of the photocatalysts reported previously. Thus, the liquid phase stripping method reported in this work has great potential in the large-scale production of MONs for efficient photocatalysis of CO 2 reduction in the gaseous phase. [ABSTRACT FROM AUTHOR]

• This review summarizes the current state of solid acid catalysts, their progression, and their implementation in the context of biodiesel production. • Solid acid catalysts are highlighted in view of their catalytic activity and recyclability for biodiesel production. • The existing challenges and potential future perspectives of solid acid catalysts were discussed. Biodiesel obtained via the transesterification process, a reaction frequently involving catalysis by homogeneous or heterogeneous catalysts, has shown considerable potential as a supplement to petroleum-based diesel; heterogeneous catalysts in the transesterification of vegetable oils are of special interest as they are relatively safer for the environment besides being endowed with recycling and regeneration attributes. The deployment of heterogeneous catalysts, however, necessitates a higher concentration of catalyst, a greater molar ratio of alcohol to oil, and an elevated temperature and pressure to produce biodiesel. A variety of solid-acid catalysts (SACs) have been utilized in the production of biodiesel, represented by Ti(SO 4)O, SO 4 /Fe‒Al‒TiO 2 , sulfonated single-wall carbon nanohorns, Ti‒SBA‒15, La‒PW‒SiO 2 /single-wall carbon nanotubes, ionic liquid grafted NH 2 ‒UiO‒66, ZrFe‒SA‒SO 3 H, magnetic SACs, sulfonic-reduced graphene oxide, CaO‒Al 2 O 3 ‒SiO 2 ‒CaSO 4 , and SiO 2 @Cs‒SO 3 H, which are deliberated here. These catalysts are highlighted and discussed in view of their exceptional catalytic activity and recyclability, in addition to comments on the existing challenges and potential future perspectives of the SACs. [Display omitted] [ABSTRACT FROM AUTHOR]

In this paper, we investigate the Cauchy problem of the generalized short-pulse equation in periodic domain. We first establish the local well-posedness of the equation in H s (S) , s ≥ 2 by taking advantage of the Kato method and present some useful conservation laws. Then, we obtain the boundedness of the solution by virtue of the conservation laws. Finally, we give a precise blow-up criterion for α > 0 (or α < 0) and get several blow-up results provided the initial data satisfies some certain conditions. [ABSTRACT FROM AUTHOR]

Abstract Aims Edaravone potentially alleviates cognitive deficits in a mouse model of Alzheimer's disease (AD). However, the mechanism of edaravone in suppressing AD progression remains unclear. We aim to investigate the mechanism of edaravone in suppressing oxidative stress-mediated AD progression in vitro. Main methods Human neuroblastoma SH-SY5Y cells were pretreated with different concentrations of edaravone prior to the induction by Aβ 25–35. Cell viability, apoptosis, reactive oxygen species, and expression of antioxidative response elements (ARE) including Nrf2, SOD, and HO-1 were assessed. Key findings The results showed that apoptosis and reactive oxygen species levels significantly increased in Aβ 25–35 -treated cells, whereas the mRNA and protein levels of Nrf2, SOD and HO-1 decreased. The opposite changes were observed in cells that were pre-treated with edaravone, particularly at a concentration of 40 μM. Aβ 25–35 -treatment suppressed Nrf2 expression and nuclear translocation were rescued by Edaravone. Genetic inhibition of Nrf2 greatly decreased the protective effect of edaravone against cell apoptosis and cytotoxicity induced by Aβ 25–35 , accompanied by decreases in SOD and HO-1 expression. Significance Activation of the Nrf2/ARE signaling pathway may underlie the protective effects of edaravone against the oxidative damage associated with Alzheimer's disease. Highlights • Edaravone resists Aβ 25–35 induced neurotoxicity in SHSY-5Y cells. • Edaravone alleviates Aβ 25–35 induced oxidative stress. • Edaravone rescues Nrf2 expression and nuclear translocation suppressed by Aβ 25–35. • Edaravone pretreatment elevates SOD and HO-1 levels in Aβ 25–35 exposed cells. [ABSTRACT FROM AUTHOR]

Microring resonators have shown promising potential for highly sensitive, label-free, real-time detection of biomolecules. Accurate quantitative detection of target molecules through use of photonic integrated circuits has been demonstrated for environmental monitoring and medical diagnostics. Here, we described the design, fabrication, and characterization of a highly sensitive, label-free microring optical resonator integrated with poly-(dimethylsiloxane) microfluidic channels, which consumes only 30 µl of sample solution. The resonance wavelength shifts resulting from the change in the effective refraction index can be measured in situ, and thus the binding events on the resonator surface, including antibody immobilization, blocking of the resonator surface, and the specific binding of antibody and antigen, can be recorded throughout the entire experimental process in real time. We measured the binding events for the detection of human immunoglobulin G. The system had a detection limit of 0.5 µg/ml, a value substantially (14 times) lower than that of a previously reported microring resonator. To verify the usefulness and adaptability of this technique, human epidermal growth factor receptor 2 was used for the detection. The microring optical resonator was able to monitor reactions between biological molecules in real time and thus can be used in quantitative detection and biological sensing with little sample consumption. [ABSTRACT FROM AUTHOR]

Graphical abstract Abstract Background Citri Reticulatae Pericarpium (CRP), Aurantii Fructus Immaturus (AFI) and Aurantii Fructus (AF) are all important Citrus species used in traditional Chinese medicines (TCMs) for the treatment of gastrointestinal disorders. Although they have been used since ancient times and are still in use today, the mechanistic basis for their regulation of adrenergic receptors (ARs) is still not clear. Purpose In this study, we aimed to determine the active components and mechanisms of action of CRP, AFI and AF in treating gastrointestinal disorders related to ARs. Methods First, the phenethylamine alkaloid components of CRP, AFI and AF were identified and compared across 30 samples of three Citrus species by UPLC-Q/TOF-MS in combination with content difference analysis. Second, the effect of the main active alkaloid component on AR-based gastrointestinal disorders was investigated by an in vivo small intestinal propulsive test and an in vitro relaxing small intestinal smooth muscle activity test. The mechanism of AR regulation of the active alkaloid was further studied by evaluating its effect on relaxing small intestinal smooth muscle in the presence of an inhibitor. Lastly, the enzymes, which played an important role in epinephrine synthesis and AR regulation, were detected by immunohistochemistry. Results Three phenethylamine AR regulators (N -methyltyramine, synephrine and hordenine) in CRP, AFI and AF were characterized. It was found that N -methyltyramine could relax mouse small intestinal smooth muscle and inhibit small intestinal propulsion. The effect of N -methyltyramine on relaxing small intestinal smooth muscle could be inhibited by a-methyl- l -tyrosine. The enzymes related epinephrine synthesis and AR function were found in the mouse small intestine. The biotransformation process that converts N -methyltyramine to epinephrine was determined. Conclusion The treatment of gastrointestinal disorders of CRP, AFI and AF is associated with their alkaloid component N -methyltyramine via the regulation of ARs, and the mechanism is considered to be the biotransformation of N -methyltyramine to epinephrine by serial synthase, which takes place at the nerves cells in small intestine. [ABSTRACT FROM AUTHOR]

Highlights • Ultrasound irradiation did not change the primary structure of BCP. • The precise structure of ultrasound-treated polysaccharide (U-600) was identified. • The degraded BCP exhibited better physicochemical properties and bioactivities. Abstract In this study, the influence of ultrasound irradiation on the characterization and bioactivities of the polysaccharide from blackcurrant fruits (BCP, molecular weight: M w = 3.26 × 104 kDa) was investigated. Two degraded polysaccharides (U-400, M w = 1.89 × 104 kDa, and U-600, M w = 1.32 × 104 kDa) were obtained by different ultrasound powers of 400 W and 600 W, respectively. Compared with BCP, U-400 and U-600 showed 63.52% and 68.85% reductions in the particle size (Z avg), respectively; moreover, the dynamic viscosity of BCP was reduced by 27.88%, and 33.63%, separately. The reducing sugar content and thermal stability increased with the increase of ultrasound intensity. The degraded polysaccharides contained the same monosaccharide species as those of BCP but at different molar ratios. Fourier transform infrared (FT-IR) and nuclear magnetic resonance (NMR) spectroscopic analysis confirmed that the degraded polysaccharides and BCP exhibited the similar structural features, which were mainly composed of six glycosidic bonds. A reduction in surface area of the flake-like structure was observed in the degraded polysaccharides compared to that of BCP, and they had no triple helix structure. Furthermore, the precise structural characteristics of U-600 were identified by 2D NMR analysis. The results of the bioactivity assays indicated that the ultrasound irradiation could evidently enhance the antioxidant (hydroxyl and superoxide radicals scavenging, lipid peroxidation inhibition, and DNA damage protection activities), α -amylase and α -glucosidase inhibition activities of BCP. These activities increased in the order of U-600 > U-400 > BCP. In particular, the DNA protection and α -amylase inhibition activities for U-600 were 52.19 ± 1.34% and 75.98 ± 0.77%, respectively, which were 2 times higher than those of BCP. U-600 prepared with the higher-intensity ultrasound exhibited the best physicochemical properties and bioactivities among the three polysaccharides. These results suggested that ultrasound irradiation was an efficient, green method to produce value-added polysaccharide for use in functional food or medicine. [ABSTRACT FROM AUTHOR]

This paper presents a review for the key literatures on magnesium oxychloride cement (MOC) to establish a comprehensive and insightful understanding of MOC. The main aim of this review is to identify the most common problems in the development and application of the MOC and the various methods to solve these problems. The characteristics of MOC including composition of hydration phases, strength development, and durability are reviewed. In particular, the various factors influencing the water resistance of MOC, the most critical characteristics of MOC, such as the reactivity of magnesium oxide, additives, and curing conditions are reviewed. Finally, the methods to improve water resistance and its related issues of MOC from the literature are summarized and future research is proposed. [ABSTRACT FROM AUTHOR]

A quaternized chitosan (QCS)@poly(ionic liquid) (PIL) hydrogel adhesive was prepared by in-situ ultraviolet (UV)-induced copolymerization of 1-vinyl-3-butyl imidazolium bromide ([BVIm][Br]) and methacryloyloxyethyl trimethylammonium chloride (DMC) in QCS aqueous solution without using any crosslinkers, which was stably crosslinked by reversible hydrogen bonding together with ion association and exhibited excellent adhesion, plasticity, conductivity and recyclability properties. Moreover, its thermal/pH-responsive behaviors and intermolecular interaction mechanism of thermal-triggered reversible adhesion were discovered, meanwhile good biocompatibility, antibacterial properties, repeated stickiness and degradability were also proved. The results showed that the newly developed hydrogel could make various tissues, organic, inorganic or metal materials adhered tightly within 1 min; after 10 binding-peeling cycles, the adhesive strength to glass, plastic, aluminum and porcine skin still remained beyond 96 %, 98 %, 92 % and 71 % of the original, respectively. The adhesion mechanism involves ion dipole interaction, electrostatic interaction, hydrophobic interaction, coordination, cation-π interaction, H-bonding and van der Waals force. For above merits, the new tricomponent hydrogel is expected to be applied in biomedical field to achieve adjustable adhesion and on-demand peeling. • Tricomponent hydrogel system of IL, DMC and QCS was designed for the first time. • The in situ IL-involved copolymerization induced by UV was free of crosslinker. • The adhesion was ideal to biological tissues and other materials within 1 min. • The adhesive exhibited good stability, biocompatibility and reused performance. • It also shows electrical/thermal/pH response behaviors and antibacterial properties. [ABSTRACT FROM AUTHOR]

In situ surface reconstruction strategy is developed to construct efficient acidic HER catalyst during the electrocatalytic process. By exploring the evolution of the catalyst, it is found that Ni-W-O amorphous layer is formed on the catalyst surface and serves as the actual active species. The synergistic effect between Ni and W modulates the electron structure of the in situ formed Ni-W-O amorphous surface layer, which may moderate the hydrogen adsorption Gibbs free energy and improve the HER catalytic activity. [Display omitted] • Efficient acidic HER catalyst is developed by an in situ surface reconstruction strategy during the electrocatalytic process. • The active species is identified to be Ni-W-O amorphous surface layer by exploring the evolution of the catalyst. • The synergistic effect between Ni and W modulates the electron structure of the in situ formed Ni-W-O amorphous surface layer. Noble metal free electrocatalysts for hydrogen evolution reaction (HER) in acid play an important role in proton exchange membrane-based electrolysis. Here, we develop an in situ surface self-reconstruction strategy to construct excellent acidic HER catalysts. Firstly, free-standing zinc nickel tungstate nanosheets inlaid with nickel tungsten alloy nanoparticles were synthesized on carbon cloth as pre-catalyst via metal–organic framework derived method. Amorphous nickel tungsten oxide (Ni-W-O) layer is in situ formed on surface of nanosheet as actual HER active site with the dissolution of NiW alloy nanoparticles and the leaching of cations. While the morphology of the free-standing structure remains the same, keeping the maximized exposure of active sites and serving as the electron transportation framework. As a result, benefiting from disordered arrangement of atoms and the synergistic effect between Ni and W atoms, the amorphous Ni-W-O layer exhibits an excellent acidic HER activity with only an overpotential of 46 mV to drive a current density of 10 mA cm−2 and a quite good Tafel slope of 36.4 mV dec−1 as well as an excellent durability. This work enlightens the exploration of surface evolution of catalysts during HER in acidic solution and employs it as a strategy for designing acidic HER catalysts. [ABSTRACT FROM AUTHOR]

By comparing the cytochrome b fragment sequences of sablefish and 16 varieties susceptible to adulteration, a real-time polymerase chain reaction (PCR) method was established to detect sablefish-derived components. The PCR method was used to analyze commercial products. The method developed was highly specific without any cross-reaction in the other 16 species and with a limit of detection for deoxyribonucleic acid (DNA) of 0.002 ng µL−1 for sablefish. In addition, the mixed muscle tissues were detected at as low as 0.01 g kg−1. The applicability of the PCR method to 50 commercial prepackaged products revealed the accuracy of this method. [ABSTRACT FROM AUTHOR]

• Biochar-amended soils as intermediate covers mitigates acid accumulation. • Biochar-amended soils as intermediate and final covers increases CH 4 yield by 25%. • Biochar-amended soils as intermediate covers enhances decomposition of MSWs. • Biochar-amended soils as landfill covers reduces ammonia accumulation. The effects of biochar-amended soils as landfill covers have been extensively studied in terms of liquid and gas permeability. However, the influences of biochar-amended soils on the performance of municipal solid wastes (MSWs) in bioreactor landfills have not been well understood. This paper investigates the potential application of biochar-amended soils as final and intermediate covers in landfills. The MSWs with biochar-amended soils as final and intermediate covers were recirculated with mature leachate in laboratory-scale bioreactors. The pH, chemical oxygen demand, ammonia and volatile fatty acids (VFAs) concentrations of leachates, mass reduction rates, settlement, methane, and total gas generations of MSWs were investigated. The results indicate that biochar-amended soils as intermediate landfill covers can provide pH-buffer capacity, increase the pH of leachate and decrease the accumulation of VFAs in the early stage of decomposition. The concentration of ammonia in the leachate with biochar-amended soils as intermediate cover is lower than that with natural soils. The application of biochar-amended soils as intermediate and/or final covers increases the biocompression ratios and settlement of MSWs. The application of biochar-amended soils as final cover slightly decreases the methane generation potential (L 0). Biochar-amended soils as intermediate covers increase L 0 by 10%, and biochar-amended soils as both intermediate and final covers enhance L 0 by 25%. The increase in the ammonia removal, settlement, and methane yield indicates the viability of biochar-amended soils as intermediate landfill covers. Further studies can focus on the long-term behaviour of MSWs with soil covers with different biochar amendment rates and particle sizes. [ABSTRACT FROM AUTHOR]

A heteropolysaccharide BCP-2 was isolated from blackcurrant fruits by successively using D4006 resin, aqueous two phase system, and Sephadex G-100 column chromatography. Its inhibitory activities against α -glucosidase, α -amylase and glycation were investigated. BCP-2 was found to be composed of galacturonic acid, rhamnose, arabinose, xylose, mannose, glucose, and galactose in a molar ratio of 1.3:2.5:5.1:1.8:1.0:72.0:4.5 with molecular weight of 2.18 × 10 4  kDa. The glycosyl linkages of (1 → 3)- α - l -Rhamnose, (1 → 4)- β - d -Mannose, (1 → 6)- α - d -Galactose and (1 → 4)- α - d -Glucose were confirmed in BCP-2. BCP-2 had no triple-helix conformation and possessed a honeycomb structure with an irregular branching shape. BCP-2 showed moderate α -amylase inhibitory activity (37.93%) and clear α -glucosidase inhibitory activity (78.42%). The inhibitory effect of BCP-2 on α -amylase was reversible and exhibited a competitively inhibitory process. Besides, BCP-2 exerted more significant anti-glycation activities than aminoguanidine during 15 days of incubation. Specifically, the inhibitory abilities were more effective on the formation of dicarbonyl compounds (66.54%) and AGEs (70.24%) than that of Amadori products (37.03%). These results suggested that BCP-2 may be a potential anti-diabetic agent. [ABSTRACT FROM AUTHOR]

In this paper we study the release of cargo from polymeric nano-carriers under shear. Vesicles formed by two star block polymers--A12B6C² (ABC) and A12B6A2 (ABA)--and one linear block copolymer--A14B6 (AB), are investigated using dissipative particle dynamics (DPD) simulations. A- and C-blocks are solvophobic and B-block is solvophilic. The three polymers form vesicles of different structures. The vesicles are subjected to shear both in bulk and between solvophobic walls. In bulk shear, the mechanisms of cargo release are similar for all vesicles, with cargo travelling through vesicle membrane with no preferential release location. When sheared between walls, high cargo release rate is only observed with ABC vesicle after it touches the wall. For ABC vesicle, the critical condition for high cargo release rate is the formation of wall-polymersome interface after which the effect of shear rate in promoting cargo release is secondary. High release rate is achieved by the formation of solvophilic pathway allowing cargo to travel from the vesicle cavity to the vesicle exterior. The results in this paper show that well controlled target cargo release using polymersomes can be achieved with polymers of suitable design and can potentially be very useful for engineering applications. As an example, polymersomes can be used as carriers for surface active friction reducing additives which are only released at rubbing surfaces where the additives are needed most. [ABSTRACT FROM AUTHOR]