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This review highlights recent advances in reaction mechanisms and catalyst design strategies for the electrochemical oxidation of ethanol over nickel-based catalysts.

[Display omitted] A novel adsorbent, aminated Fe 3 O 4 (Fe 3 O 4 -NH 2)/graphite oxide (GO)/carboxylated cross-linked β-cyclodextrin polymer (CDP-COOH) composite, was fabricated for influential removal of various types of dyes from waters. The morphology and structure of resulting Fe 3 O 4 -NH 2 /GO/CDP-COOH composite was studied by SEM, two-dimensional EDS map, FTIR, WAXD, XPS, TGA, and zeta potential meter, and its saturation magnetization was determined to be 46.3 emu/g by VSM. The maximal sorption capacities of Fe 3 O 4 -NH 2 /GO/CDP-COOH composite for methylene blue (MB, as a model of cationic dyes) and Congo red (CR, as a model of anionic dyes) at 303 K were 201.75 mg/g and 2211.05 mg/g, respectively, which can be mainly assigned to multiple adsorptive forces like electrostatic attractions, hydrogen bonds, host–guest self-assembly interactions, π-π electron cloud interactions, and Lewis acid-base interactions. The dye sorption by the Fe 3 O 4 -NH 2 /GO/CDP-COOH composite had a spontaneous nature according to the sorption thermodynamic calculation and can be well explained by pseudo-second-order model. The Langmuir and Freundlich models could explain the sorption isotherms of Fe 3 O 4 -NH 2 /GO/CDP-COOH composite for MB and GO, respectively. The Fe 3 O 4 -NH 2 /GO/CDP-COOH composite possessed many other advantages including the good sorption capability for different heavy metal ions (like Pb2+, Ni2+, and Cu2+) and organic compounds (like dichlorophenol and propranolol) as well as the good recyclability and reusability. [ABSTRACT FROM AUTHOR]

Pervious concrete is a special type of concrete that is of high porosity and contains no or a small amount of fine aggregate, and it is an important basic material for sponge city construction. The presence of a large number of connected pores inside pervious concrete leads to a marked difference in durability failure mechanism compared with that of ordinary concrete.

Stroke is a leading cause of global mortality and severe disability. However, current strategies used for treating ischemic stroke lack specific targeting capabilities, exhibit poor immune escape ability, and have limited drug release control. Herein, we developed an ROS-responsive nanocarrier for targeted delivery of the neuroprotective agent rapamycin (RAPA) to mitigate ischemic brain damage. The nanocarrier consisted of a sulfated chitosan (SCS) polymer core modified with a ROS-responsive boronic ester enveloped by a red blood cell membrane shell incorporating a stroke homing peptide. When encountering high levels of intracellular ROS in ischemic brain tissues, the release of SCS combined with RAPA from nanoparticle disintegration facilitates effective microglia polarization and, in turn, maintains blood–brain barrier integrity, reduces cerebral infarction, and promotes cerebral neurovascular remodeling in a mouse stroke model involving transient middle cerebral artery occlusion (tMCAO). This work offers a promising strategy to treat ischemic stroke therapy.

The prime camera with a mosaic charge-coupled device (CCD) array is the imaging terminal of the wide field survey telescope (WFST), and the flatness of its focal plane array (FPA) is one of the critical indicators that determine the imaging quality of the telescope. The FPA works at $- 100~^{\circ }$ C in a vacuum Dewar to suppress the dark current of CCDs. A large-size FPA of high flatness is hard to realize due to the influence of multiple factors, such as geometric tolerance, force, and temperature deformation. To address this issue, a CCD mosaicking technique based on an error accumulation model is proposed. First, the error source of FPA is analyzed with high-precision measurement and finite element simulation. Second, an assembly deviation simulation calculation model is established based on the actual contact surface morphology characteristics, and the error transfer process is analyzed by combining the small displacement torsor (SDT) and homogeneous transformation matrix (HTM). Then, the effects of force and temperature deformation on each CCD are superimposed independently by HTM, and the feasibility is verified by finite element simulation. Finally, the mosaic FPA of the prime focus camera (PFC) is completed based on this model. Comparing the simulated and measured results, the flatness of the FPA at room temperature reaches a PV of $15.53~\mu $ m. The confidence interval for the flatness of the FPA is determined as [13.48, 17.60] $\mu $ m, with a confidence level of 95%. Also, upon comparing the distribution of CCDs between measurement and simulated assembly, it is evident that only a subset of CCDs shows a height deviation of $0.8~\mu $ m, thus affirming the effectiveness of the simulated assembly process. The FPA suffers a significant bow-shaped deformation at low temperatures, and 99.18% of the measured points are within $16.30~\mu $ m.

In vehicular cloud computing (VCC), cloud servers provide enormous storage and powerful computing capacity to Vehicular Ad-hoc Networks (VANETs). Resource-constrained vehicles outsource data to vehicular cloud platforms for timely traffic safety services, e.g., navigation, accident alarms, etc. Auditing the authenticity of data has become a critical issue in outsourcing data to untrusted servers. Existing data audit methods encode all data with error correction codes (ECC) techniques that retrieve corrupted data by downloading all data. The communication overhead of such methods is $O(n)$ ($n$ is the number of data blocks) which is unbearable for vehicles with limited resources. In addition, these schemes employ an inaccurate privacy-preserving model. This will lead to data leakage in the third-party audit process. Although they use randomness to confuse parts of the proof that is used to prove the data state, a small amount of information is still distinguishable. For such, in this paper, we propose a practical data audit scheme with retrievability and indistinguishable privacy-preserving to efficiently audit the state of outsourced data. We improve the Invertible Bloom Filter (IBF) to compress redundancy locally, which can retrieve corrupted data without prior context. Furthermore, we define an indistinguishable privacy-preserving model to capture the complete semantics of repeated audit attacks and achieve indistinguishability in the audit. We prove that our scheme is secure against adaptive chosen message attacks and is indistinguishable privacy-preserving against repeated audit attacks. The experiment results demonstrate that for 1.9 GB data when $\sqrt[]{n}$ blocks are corrupted, auditors complete a check in 3.31 seconds with 99% confidence, and vehicles retrieve corrupted data in 3.16 seconds with 16.67 MB communication overhead.

The comparative evaluation related to the promotion of Ru and Fe on Ni/ZrO2catalysts showed that Ru-modified Ni/ZrO2with Ni-Ru alloy formation and higher amount of oxygen vacancies enabled higher CO2methanation activity.

The loop impedance-based criterion (LIC) is a practical approach for studying the sub-synchronous oscillation (SSO) instability induced by converter-interfaced wind turbine generators (WTGs) via checking whether the resistance is positive or not. However, few existing works have discussed the background mathematical theory of such criterion. In this paper, a theoretical impedance solving method is raised based on a forced oscillation analysis method, which is efficient to obtain accurate impedance and can connects the state-space function, eigenvector and impedance inherently. Therefore, the applicability of LIC can be revealed in different stability regions from the viewpoint of the strict eigen-analysis based method (EBM). The general LIC stability criteria is then derived, and the conditions where LIC may cause misjudgment are discussed. Cases considering different operating scenarios are conducted to verify the proposed impedance calculation method and illustrate the connections and differences between LIC and EBM.

Self-organizing mechanical instabilities provide a promising route to programmatically micro/nanopatterning two-dimensional (2D) materials, which relies on deterministic control of instability-induced self-assemblies. However, due to ultra-low flexural rigidities, various non-deterministic multi-mode coupling mechanical instabilities are extremely prone to be triggered in 2D materials, which make it difficult to controllably self-assemble 2D nanocrystals into designed mode. Here, we report a deterministic mode of self-assembly in atomically thin 2D materials via mode-decoupled instabilities, which is the key to control self-assembled morphologies. Moreover, we capitalize on intermediate-multifunctional layers (IMLs) to construct 2D-materials/IML/substrate trilayer systems, which can implement three-order trans-scale directed and dynamic self-assemblies of 2D materials. Benefited from the unique properties induced by deterministic self-assemblies, we reported a concept for the fabrication of deterministically self-assembled micro/nano-electronics of 2D materials, such as ultra-fast gesture and anisotropic tactile sensors. The deterministic self-assemblies can considerably advance the development of post-programmable micro/nanopatterning technology and self-assembled electronics of 2D materials.

The advances and challenges of power-to-methane, especially the methanation process, including operation parameters, catalyst categories and roles, and reaction/deactivation mechanisms, are discussed in detail.

In vehicular edge computing (VEC), the execution of offloading task needs not only the task data uploaded by the requesting vehicle, but also the additional data to support the task to be executed successfully, and how to efficiently cache and access these supporting data becomes the key issue for task offloading in VEC. In this paper, we study the efficient caching mechanism to minimize the acquisition delay of the supporting data. Firstly, with the software defined network (SDN) based VEC framework, we analyze the acquisition ways of the supporting data and the caching collaboration between VEC servers. Then, according to the density of the requesting vehicles, we divide the VEC coverage into dense and ordinary areas. With the consideration of the similarity of the requested data and the distance between edge servers, the edge servers are clustered into multiple groups based on K-mean++ algorithm. Finally, each server's storage space is divided into three partitions, and the most beneficial data for itself, its group and the whole system are respectively stored in these partitions. Based on service area dividing, server grouping and storage space partitioning, we propose an efficient edge-cloud collaborative caching strategy, which can reduce the delay of data migration while task execution. Simulation results show that, compared with other schemes, the proposed caching strategy has better performance in terms of average data migration delay and application QoS.

In this research, a method employing micro-extrusion was designed to produce the micro-scaled barrel-shaped parts with complex geometrical features to study the feasibility of the proposed microforming method and its grain size effect on the formability of the complicated internal features in terms of deformation behavior, material evolution, accuracy of dimensions and final components quality. The results reveal that the deformation behavior is highly affected by grain size and becomes unpredictable with increased grain size. In addition, assembly parameters including feature dimension, tolerance and coaxiality also vary with grain size, and the variation of grain size needs to be accommodated by different assembly types, viz., clearance fit or transition fit. From the microstructural evolution aspect, it was identified there were two dead zones and four shear bands, and the formation of these deformation zones was barely affected by the variation in grain size. Though bulges, cracks, and fracture induced voids were observed on the surface of the final components, tailoring the microstructure of the working material with finer grains could significantly avoid these defects. This study advances the understanding of forming microparts by extrusion processes and provides guidance for microforming of similar microparts.

This paper investigates an unmanned aerial vehicle (UAV)-enabled maritime secure communication network, where the UAV aims to provide the communication service to a legitimate mobile vessel in the presence of multiple eavesdroppers. In this maritime communication networks (MCNs), it is challenging for the UAV to determine its trajectory on the ocean, since it cannot land or replenish energy on the sea surface, the trajectory should be pre-designed before the UAV takes off. Furthermore, the take-off location of the UAV and the sea lane of the vessel may be random, which leads to a highly dynamic environment. To address these issues, we propose two reinforcement learning schemes, Q-learning and deep deterministic policy gradient (DDPG) algorithms, to solve the discrete and continuous UAV trajectory design problem, respectively. Simulation results are provided to validate the effectiveness and superior performance of the proposed reinforcement learning schemes versus the existing schemes in the literature. Additionally, the proposed DDPG algorithm converges faster and achieves higher utilities for the UAV, compared to the Q-learning algorithm.

This paper describes control algorithm of minimum energy loss in the aeration process of wastewater treatment in the activated sludge system. The basic equations of the aeration process have been proposed in this paper with the dissolved oxygen concentration (DO) and the amount of sludge discharge (QW) being dual-parameter control variables and the organic matter concentration Sand the microbial concentration Xin the aeration tank being the state variables. Based on the present study on optimization control of wastewater treatment, the multivariable optimal control model with restriction factors have been presented in the paper. The model with modern control theory and system analysis are introduced into the field of activated sludge wastewater treatment. It takes the two most important control parameters (DO &QW), effluent quality as restriction factor. The minimum energy consumption in the aeration process is used as the objective function. This approach has been carried out and the results show that adopting optimal control strategy in the aeration process can effectively conserve energy with the assurance of effluent water quality.

Ulcerative colitis (UC) is a chronic inflammatory disease of the gastrointestinal tract, which is closely related to gut barrier dysfunction. Emerging evidence shows that interleukin-22 (IL-22) derived from group 3 innate lymphoid cells (ILC3s) confers benefits on intestinal barrier, and IL-22 expression is controlled by aryl hydrocarbon receptor (AhR). Previous studies show that baicalein protects the colon from inflammatory damage. In this study we elucidated the molecular mechanisms underlying the protective effect of baicalein on intestinal barrier function in colitis mice. Mice were administered baicalein (10, 20, 40 mg·kg−1·d−1, i.g.) for 10 days; the mice freely drank 3% dextran sulfate sodium (DSS) on D1–D7 to induce colitis. We showed that baicalein administration simultaneously ameliorated gut inflammation, decreased intestinal permeability, restored tight junctions of colons possibly via promoting AhR/IL-22 pathway. Co-administration of AhR antagonist CH223191 (10 mg/kg, i.p.) partially blocked the therapeutic effects of baicalein in colitis mice, whereas AhR agonist FICZ (1 μg, i.p.) ameliorated symptoms and gut barrier function in colitis mice. In a murine lymphocyte line MNK-3, baicalein (5–20 μM) dose-dependently increased the expression of AhR downstream target protein CYP1A1, and enhanced IL-22 production through facilitating AhR nuclear translocation, these effects were greatly diminished in shAhR-MNK3 cells, suggesting that baicalein induced IL-22 production in AhR-dependent manner. To further clarify that, we constructed an in vitro system consisting of MNK-3 and Caco-2 cells, in which MNK-3 cell supernatant treated with baicalein could decrease FITC-dextran permeability and promoted the expression of tight junction proteins ZO-1 and occluding in Caco-2 cells. In conclusion, this study demonstrates that baicalein ameliorates colitis by improving intestinal epithelial barrier via AhR/IL-22 pathway in ILC3s, thus providing a potential therapy for UC.

Understanding the deactivation process is of great importance for tailored design of oxygen evolution electrocatalysts with increased stability.

MicroRNAs (miRNA) have been shown to be associated with tumor diagnosis, prognosis, and therapeutic response. MiR-328-3p plays a significant role in breast cancer growth; however, its actual function and how it modulates specific biological functions is poorly understood. Here, miR-328-3p was significantly downregulated in breast cancer, especially in patients with metastasis. Mitochondrial carnitine palmitoyl transferase 1a (CPT1A) is a downstream target gene in the miR-328-3p-regulated pathway. Furthermore, the miR-328-3p/CPT1A/fatty acid β-oxidation/stemness axis was shown responsible for breast cancer metastasis. Collectively, this study revealed that miR-328-3p is a potential therapeutic target for the treatment of breast cancer patients with metastasis, and also a model for the miRNA-fatty acid β-oxidation-stemness axis, which may assist inunderstanding the cancer stem cell signaling functions of miRNA.

Background: Hepatocellular Carcinoma (HCC) is a primary liver cancer with high mortality. Paeoniflorin is a pinane monoterpene picroside with anti-tumor effect isolated from Chinese peony root and white peony root. Objective: The study was conducted to investigate the underlying mechanism of Paeoniflorin (PF) regulating Hepatocellular Carcinoma (HCC) progression via 5-hydroxytryptamine receptor 1D (5-HT1D). Methods: HepG2 and SMMC-7721 hepatoma cells were treated with different concentrations of PF (0, 5, 10, 20 μM). Cell proliferation, apoptosis, migration, and invasion were examined by CCK-8 and colony formation assays, flow cytometry, wound healing assay, and transwell assay, respectively. RTqPCR assay was used to detect the expression level of 5-HT1D, and Western blot assay was used to detect the expressions of 5-HT1D and Wnt/β-catenin pathway-related proteins. Results: With the increase in PF concentration, the mRNA levels of 5-HT1D in HepG2 and SMMC- 7721 hepatoma cells were decreased in a dose-dependent manner, and the proliferation, colony formation, migration and invasion ability of cells were gradually weakened, while the apoptosis rate was gradually increased. Overexpression of 5-HT1D significantly promoted the proliferation, colony formation, migration and invasion of HepG2 and SMMC-7721 cells, and increased the expression of Wnt/β-catenin pathway-related proteins, β -actenin, survivin, C-myc, and Cyclin D1. Furthermore, 5-HT1D overexpression could reverse the effect of PF on hepatoma cells and inhibit the expressions of Wnt/β-catenin pathway-related proteins. Conclusion: PF may inhibit the progression of HCC by blocking Wnt/β-catenin pathway expression through downregulating 5-HT1D.

Electrochemical water splitting is a process to store renewable energy in hydrogen, which is a green energy carrier producing only water when combusted. However, the overall electrochemical water splitting is limited by the low efficiency of the anodic oxygen evolution reaction (OER) leading to a high overpotential. In this study, finely dispersed cobalt particles supported on graphene are prepared as an anodic catalyst and coupled with phosphate activation to enhance and stabilize OER activity. The small particles enable a high exposure of the surface active sites. Also, the highly conductive graphene backbone accelerates electron transport. Activation by phosphate in the electrolyte leads to the formation of the active Co(iii) species with enriched oxygen vacancies meanwhile facilitating the kinetics. The finely dispersed cobalt particles supported on graphene together with phosphate activation lead to high electrochemical surface area and intrinsic activity, achieving a current density of 10 mA cm−2at an overpotential of 0.35 V and a low Tafel slope of 45 mV per decade, together with good stability. The cobalt mass based current density is 19–8000 times higher than current benchmarking catalysts.

Coronavirus disease 2019 (COVID-19) has rapidly evolved into a pandemic, causing a global public health crisis. Many frontline healthcare workers providing ear, nose and throat services have been reported to contract COVID-19 at work. Early during the COVID-19 outbreak, several medical professionals in Otolaryngology-Head and Neck Surgery were infected in Wuhan, China. A series of measures were then taken immediately, which successfully halted the spread of the disease. Here we would like to share the lessons we have learned, and our experience to protect our health care workers during the COVID-19 pandemic.

Oroxindin is a flavonoid isolated from the traditional Chinese medicine Huang-Qin, which has shown various pharmacological activities including anti-inflammatory, antitumor, antioxidant, etc. Thus far, the effect of oroxindin on colonic inflammation and the underlying mechanism remain unknown. In this study, we investigated the tissue distribution of oroxindin and its therapeutic effects on ulcerative colitis (UC) as well as the underlying mechanisms. UC model was established in mice by administrating dextran sulfate sodium (DSS) in drinking water for 7 d. We first showed that oroxindin was largely absorbed by the colon as an active ingredient after normal mice received Huang-Qin-Tang, a traditional Chinese medicine decoction. UC mice were then treated with oroxindin (12.5, 25, 50 mg ·kg−1·d−1, i.g.) for 10 d. We found that oroxindin treatment greatly suppressed massive macrophages infiltration and attenuated pathological changes in colonic tissue. Furthermore, oroxindin treatment significantly inhibited the generation of IL-1β and IL-18 in the colon via inhibiting the nucleotide-binding oligomerization domain-like receptor 3 (NLRP3) inflammasome formation and activation. In cultured macrophages, LPS induced NLRP3 inflammasome formation and caspase-1 activation, which were suppressed by oroxindin (12.5–50 μM). In LPS-treated macrophages, oroxindin dose-dependently restored the expression of TXNIP protein, leading to suppressing TXNIP-dependent NF-κB activation. In conclusion, these results demonstrate that oroxindin could be absorbed by the colon and attenuate inflammatory responses via inhibiting NLRP3 inflammasome formation and activation, which is related to the inhibitory effect on TXNIP-dependent NF-κB-signaling pathway. Hence, oroxindin has the potential of becoming an effective drug for treating UC.

Background: Except conventional treatments, research on medical approach for radioiodine-refractory differentiated thyroid cancer (RR-DTC) was considered particularly challenging. Sorafenib, a novel biological agent, has been widely studied in the treatment of RR-DTC for years. We performed a systematic review and meta-analysis to explore the efficiency and safety of treating RR-DTC patients with sorafenib. Methods: An electronic search on PubMed/Medline and Embase was carried out to search associated articles. Fixed-effects or random-effects models were chose according to the heterogeneity. Results: A total of 15 eligible studies (636 patients) were included. As shown by the only randomised clinical trial-DECISION, sorafenib significantly improved progression-free survival (PFS) compared with placebo in patients with progressive RR-DTC. The pooled analysis indicated that there were 26% patients (95% CI: 0.19–0.34) achieved partial response (PR), and 44% patients (98% CI: 0.39–0.48) achieved stable disease (SD). The most frequent adverse effects (AEs) observed included hand-foot syndrome (HFS), diarrhoea, fatigue, alopecia, weight loss (WS) and rash, the incidence of all grades AEs for which were 71%, 60%, 59%, 55%, 51% and 50%, respectively. There were 68% patients (252/368), who had a dose reduction because of the drug toxicities and AEs. Conclusions: Sorafenib could improve PFS in patients with progressive RR-DTC, comparing with placebo. Due to the resistance to conventional treatments, sorafenib is considered as a promising treatment for RR-DTC by most physicians specialised in this field. However, the use of sorafenib should be cautious due to a high incidence of AEs caused by the agent. More effective agents with less toxicities are warranted.

Protoplast electrofusion between callus protoplasts of cultivar TMS60444 and mesophyll protoplasts of cultivar SC8 was performed as an approach for the genetic improvement of cassava. The fusion products were subsequently cultured in protoplast culture medium (TM2G) with gradual dilution for approximately 1–2 months. Then the protoplast-derived compact calli were transferred to suspension culture medium (SH) for suspension culture. The cultured products developed successively into embryos, mature embryos, and shoots on somatic embryo emerging medium (MSN), embryo maturation medium (CMM), and shoot elongation medium (CEM), respectively. And the shoots were then rooted on Murashige and Skoog (1962) medium (MS). Sixty-six cell lines were obtained and 12 of them developed into plantlets. Based on assessment of ploidy level and chromosome counting, four of these plantlets were tetraploid and the remaining eight were diploid. Based on assessment of ploidy level and simple sequence repeat (SSR) analysis, nine tetraploid cell lines, one diploid variant plant line and nine variant cell lines were obtained. The diploid variant plant line and the nine variant cell lines all showed partial loss of genetic material compared to that of the parent TMS60444, based on SSR patterns. These results showed that some new germplasm of cassava were created. In this study, a protocol for protoplast electrofusion was developed and validated. Another important conclusion from this work is the confirmation of a viable protocol for the regeneration of plants from cassava protoplasts. Going forward, we hope to provide technical guidance for cassava tissue culture, and also provide some useful inspiration and reference for further genetic improvement of cassava.

Exposure to phthalate acid esters (PAEs) has been found to have adverse effects on reproduction of human and animal. However, the effects on the semen quality are controversial. In this study, we have collected paired blood and sperm samples from patients (n = 103) at a medical clinic in Guangzhou, China, to determine the concentrations of eight phthalate metabolites (m-PAEs). The concentration ranges of ∑8m-PAEs were 2.7–55 and 0.99–17 ng/mL in blood and semen samples, respectively. MEHP (median, 3.6 ng/mL in blood and 0.55 ng/mL in semen) and MnOP (median, 3.4 ng/mL in blood and 0.69 ng/mL in semen) were the predominant analytes in both blood and semen samples. However, analytes were not correlated in paired blood and semen. Semen motility was significantly associated to the concentrations of ∑8m-PAEs in semen, but it did not associate to the concentrations of PAEs in blood. Multi-linear regression analysis, including concentrations of PAEs in both blood and semen, as well as BMI, occupation, living habits, suggested that exposure to PAEs at current environmental levels had very limited effects on semen quality of population in Guangzhou, China.