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Lignin is the only renewable aromatic material in nature and contains a large number of oxygen-containing functional groups. High-value and green utilization of "lignin-to-chemicals" can be realized via using lignin to produce fine chemicals such as phenols and carboxylic acids, which can not only reduce the waste of lignin in the process of lignocellulosic biomass treatment, but gradually make the substitution of traditional fossil fuels come true. The hydrogenolysis process under catalysis of metal catalyst has high product selectivity and less impurity, which is suitable for the production of same type or single fine chemicals. Hydrogenolysis of lignin via metal catalysts to produce lignin oil, and further modification of functional groups (e.g. methoxyl, alkyl and hydroxyl group) of depolymerized monomers in the bio-oil to yeild phenols and terephthalic acid are reviewed, and catalytic mechanisms are briefly summarized in this paper. Finally, the problems of lignin catalytic conversion existing currently are investigated, and the future development of this field is also prospected. [ABSTRACT FROM AUTHOR]

The rapid development of artificial intelligence (AI) and big data technologies has profoundly changed the way of human life and work, and in the healthcare field, the related product design is moving towards the trend of digitalization, intelligence, and personalization. The growing demands for personalised healthcare have contributed to a boom in product design theories in related fields. However, it is difficult to measure product users' preferences in precise numerical terms to make strategic decisions in product design. To fill this gap, this study proposes a framework for virtual reality (VR) healthcare product design based on a data-driven concept and develops a VR virtual roaming system for system users guided by this theory. The data-driven concept incorporates AI and big data technologies into product design, helping to shift the design of medical products towards a data-centred approach. Ultimately, an ergonomic experiment was conducted and a case study was carried out to assess the user's experience using brain function data to enable data-driven VR value-added services. This study provides a new perspective on rehabilitation product design, opening the way for better personalised healthcare delivery. [ABSTRACT FROM AUTHOR]

• Two kinds of abnormal biomechanical stimulation models were used both in vivo and in vitro. • Temporomandibular joint osteoarthritis is related to mitochondrial injury. • Mitochondrial injury can be caused by an increase in nitric oxide. • Targeting mitochondrial pathway can be a strategy for the treatment of osteoarthritis. Chondrocyte apoptosis is a pathological manifestation of osteoarthritis. The goal of this report was to explore the role of nitric oxide in chondrocyte apoptosis in osteoarthritic mandibular condylar cartilage. This study used our reported experimental unilateral anterior crossbite in vivo rat model and chondrocyte fluid flow shear stress in vitro model. In the in vivo model, apoptosis in the mandibular condylar cartilage was assessed by detection of the TUNEL-positive cells, the expression levels of inducible nitric oxide synthase (iNOS), caspase-9, and caspase-3. In the in vitro model, mitochondrial injury was evaluated, the nitric oxide and superoxide dismutase (SOD) production levels were measured, and the cytochrome C (Cyt C) expression level was detected. The expression levels of apoptosis-related proteins B cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), caspase-3, and poly-ADP-ribose polymerase 1 (PARP1) were analyzed in both in vivo and in vitro models. The effects of iNOS inhibitor on chondrocyte apoptosis were also investigated. The data indicated that the unilateral anterior crossbite induced cartilage degeneration with enhanced cell apoptosis and stimulated the expression of caspase-3/-9 and iNOS. The fluid flow shear stress upregulated the expression of iNOS, SOD, and nitric oxide, reduced mitochondrial membrane potential, and promoted Cyt C to enter the cytoplasm. All of these changes were reversed by iNOS inhibitors. The abnormal occlusion stimulated mitochondrial damage and apoptosis of the chondrocytes in the mandibular condylar cartilage mediated by nitric oxide. Inhibiting nitric oxide production could be a therapeutic strategy. [ABSTRACT FROM AUTHOR]

Cubic silicon carbide (β-SiC) thin films were synthesized on cemented carbide (WC–Co) substrates as an interlayer for modifying the adhesion of diamond coatings. The influence of varying the hydrogen (H 2 )/tetramethylsilane (TMS) flow ratios on the microstructure, phase composition and adhesion of the β-SiC films was investigated. It was found that with the increase of the H 2 /TMS flow ratios, the SiC crystallite size increases from 6.5 nm to 22.2 nm. When the flow ratio was 40:5, the film was formed of loose cauliflower-like agglomerates, containing SiC granular particles. With the flow ratio increased from 40:5 to 120:5, the films became more uniform and denser, resulting in adhesion enhancement. However, when the ratio increased from 160:5 to 200:5, clusters composed of faceted particles replaced the agglomerates, and the adhesion reduced. The β-SiC film deposited with a H 2 /TMS flow ratio of 120:5 possessed a more uniform and denser structure, as well as better adhesion than the others. After subsequent diamond deposition, homogeneous nanocrystalline diamond coatings were realized on the β-SiC interlayered substrates. Compared with the results on the well-known two-step chemically etched substrates, the diamond coatings deposited on the substrates with the β-SiC interlayer possess excellent adhesion. It was also validated in this research that the β-SiC interlayer deposited with a H 2 /TMS flow ratio of 120:5 was effective in enhancing the adhesion of diamond coatings prepared on WC–Co substrates. [ABSTRACT FROM AUTHOR]

In this paper, bi-layer (SiC + diamond) coatings were synthesized on 0.8-mm-diameter cemented carbide micro-end mills. The influences of SiC interlayers and diamond coatings on the morphologies, phase composition and fracture strength were investigated. The cutting performance of the bi-layer (SiC + diamond) coated tools was validated by dry cutting of aluminum alloys. The results indicated that the binder Co reacted with SiC to form cobalt silicides (i.e., Co 2 Si and CoSi), suggesting that the SiC interlayer suppressed the deleterious effects of Co, successfully. Neither the presence of the SiC interlayer nor the bi-layer coatings reduced the fracture resistance of the tools. The workpieces had a better surface finish after being cut by the coated tools than those cut by the uncoated tools. This result indicated that the bi-layer (SiC + diamond) coated tools exhibited better cutting performance than the uncoated tools. Thus, SiC interlayers were demonstrated as a suitable option for adherent diamond coatings on the cemented carbide components and cutting tools. [ABSTRACT FROM AUTHOR]

SiC films were synthesized on WC-Co substrate as interlayers for improving the adhesion of diamond coatings. The influence of the substrate temperature on the SiC films was investigated. The results showed that when the temperature was 600 °C, the film was formed of loose agglomerates piled up by SiC nanoparticles. As the temperature increased to 850 °C, shell structure composed of SiC particles and graphite replaced the agglomerates. When the temperature exceeded 950 °C, flower-like SiC clusters and graphite spherical particles coexisted in the surface, and Co 2 Si particles embedded at the SiC/substrate interface. SiC films deposited at 600 °C, 850 °C and 950 °C were typically used as interlayer for diamond deposition. The coatings exhibited the similar nano-diamond structure. However, the diamond coating on the interlayer produced at 850 °C possessed the best adhesion; and the diffusion of Co was effectively inhibited by SiC interlayer which would not interfere with the process of diamond deposition. [ABSTRACT FROM AUTHOR]

The maturity of Industrial 4.0 technologies (smart wearable sensors, Internet of things [IoT], cloud computing, etc.) has facilitated the iteration and digitization of rehabilitation assistive devices (RADs) and the innovative development of intelligent manufacturing systems of RADs, expanding the value-added component of smart healthcare services. The intelligent manufacturing service mode, based on the concept of the product life cycle, completes the multi-source data production process analysis and the optimization of manufacturing, operation, and maintenance through intelligent industrial Internet of things and other means and improves the product life cycle management and operation mechanism. The smart product-service system (PSS) realizes the value-added of products by providing users with personalized products and value-added services, service efficiency, and sustainable development and gradually forms an Internet-product-service ecosystem. However, research on the PSS of RADs for special populations is relatively limited. Thus, this paper provides an overview of an IoT-based production model for RADs and a smart PSS-based development method of multimodal healthcare value-added services for special people. Taking the hand rehabilitation training devices for autistic children as a case, this paper verifies the effectiveness and availability of the proposed method. Compared with the traditional framework, the method used in this paper primarily helps evaluate rehabilitation efficacy, personalizes schemes for patients, provides auxiliary intelligent manufacturing service data and digital rehabilitation data for RAD manufacturers, and optimizes the product iteration development procedures by combining user-centered product interaction, multimodal evaluation, and value-added design. This study incorporates the iterative design of RADs into the process of smart PSS to provide some guidance to the RADs design manufacturers. [ABSTRACT FROM AUTHOR]

Dual activation of the glucagon receptor (GCGR) and glucagon-like peptide 1 receptor (GLP-1R) has the potential to lead to an effective therapy for the treatment of diabetes and obesity. Here, we report the discovery of a series of peptides with dual activity on GLP-1R and GCGR that were discovered by rational design. Structural elements of oxyntomodulin (OXM), glucagon or exendin-4 were engineered into the selective GLP-1R agonist Xenopus GLP-1 (xGLP-1) on the basis of sequence analysis, resulting in hybrid peptides with potent dual activity at GLP-1R and GCGR. Further modifications with fatty acid resulted in a novel metabolically stable peptide (xGLP/GCG-15) with enhanced and balanced GLP-1R and GCGR activations. This lead peptide was further explored pharmacologically in both db/db and diet-induced obesity (DIO) rodent models. Chronic administration of xGLP/GCG-15 significantly induced hypoglycemic effects and body weight loss, improved glucose tolerance, and normalized lipid metabolism, adiposity, and liver steatosis in relevant rodent models. These preclinical studies suggest that xGLP/GCG-15 has potential for development as a novel anti-obesity and/or anti-diabetic candidate. Considering the equal effects of xGLP/GCG-15 and the clinical candidate MEDI0382 on reverse hepatic steatosis, it may also be explored as a new therapy for nonalcoholic steatohepatitis (NASH) in the future. Image 1 • Novel GLP-1R/GCGR coagonists derivatized from the peptide backbone of XenGLP-1. • xGLP/GCG-15 exhibited enhanced and balanced GLP-1R and GCGR activation potency. • xGLP/GCG-15 showed prominent hypoglycemic effects in db/db mice. • xGLP/GCG-15 significantly induced body weight loss in DIO mice. [ABSTRACT FROM AUTHOR]

In present work, Al-7Si-4Cu alloys with/without 0.28 wt % Cd addition were fabricated. Both alloys were solution treated at 500 °C for 10 h, followed by quenching and subsequently ageing at 165 °C for different times of 0.5–20 h. Results showed that hardness, strength and ductility at peak-aged state for Cd-doped alloy were simultaneously enhanced by comparing with Cd-free alloy. Quantitative analysis results of microstructure indicated that with Cd addition a finer and denser microstructure of θ′ can be obtained. Based on microstructure characterization as well as thermodynamics and kinetics calculations, the mechanism for obtaining a finer and denser θ′ was discussed, which was considered as a result of the pre-precipitation and heterogeneous nucleation effect of Cd-rich particles. Improved mechanical properties for Cd-doped alloy were discussed to be ascribed to the precipitation of larger number density and less size of θ′. The increase of yield strength with Cd was quantitatively described by the strengthening models. The results indicated that yield strength increment in alloy B was dominated by strengthening contribution of finer and denser θ′ precipitates. Image 1 • Al-Si-Cu-Cd alloy was fabricated with finer and denser θ′ by Cd addition. • Hardness, strength and ductility were enhanced simultaneously in the Cd-doped alloy. • Heterogeneous nucleation effect of Cd-rich particles on refining θ′ was found. • Strengthening and toughening mechanisms in the Cd-doped alloy were discussed. [ABSTRACT FROM AUTHOR]

A series of rasagiline-clorgyline hybrids was designed, synthesized and investigated in vitro for their inhibition of monoamine oxidase and amyloid-β aggregation. Most of compounds were found to be selective and highly potent hMAO-B inhibitors showing IC 50 values in the nanomolar, and exhibited a moderate inhibition of amyloid-β aggregation. 7-((5-(methyl(prop-2-yn-1-yl)amino) pentyl)oxy)chroman-4-one (6j) was the most interesting compound identified in this research, endowed with higher hMAO-B potency (IC 50 = 4 nM) and selectivity (SI > 25000) compared to the reference selective inhibitor rasagiline (IC 50 = 141 nM, SI > 355), and exhibited good inhibitory activity against Aβ 1-42 aggregation (40.78%, 25 μM). Kinetic and molecular modeling studies revealed that 6j was a competitive reversible inhibitor for hMAO-B. Moreover, compound 6j displayed low toxicity and good neuroprotective effects in SH-SY5Y cell assay, and could penetrate the blood-brain barrier according to the parallel artificial membrane permeability assay. Pharmacokinetics assay revealed that compound 6j possessed good pharmacokinetic profiles after intravenous and oral administrations. Overall, these results highlighted that compound 6j was an effective and promising multitarget agent against Alzheimer's disease. Image 1 • Twenty rasagiline-clorgyline hybrids were designed and synthesized. • All compounds were highly selective and potent h MAO-B inhibitors. • 6j exhibited low nanomolar inhibition for MAO-B and good inhibition for Aβ 1-42 aggregation. • 6j showed neuroprotective effects and could penetrate the BBB. • 6j had good pharmacokinetic characteristics after intravenous and oral administrations. [ABSTRACT FROM AUTHOR]