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This article presents the experimental characterization of SiC MOSFETs exposed to heavy-ion irradiation. Different leakage paths related to the drain bias used during the tests are observed, suggesting different damage sites in the devices, which can be further verified through the post-irradiation measurements. TCAD simulations are utilized to explore the underlying failure mechanisms. Based on the evolution of the gate oxide field, it is shown that the damage first occurs in the middle of the JFET region, while gradually spreads to the channel region with the increase of drain bias, but terminates at the source region. A preliminary model to roughly emulate the drain bias dependence of such degradation behaviors is developed, and the simulation results match the experiments well. Additionally, the emission microscope (EMMI) is carried out so as to detect the latent damage at the die level. The findings in this article demonstrate that more attention should be paid to the damaged gate oxide induced by the heavy-ion strike before SiC MOSFETs could act as a drop-in replacement of Si-based counterparts in avionic applications.

The glycosaminoglycans (GAGs) on cell surfaces play significant roles during cancer development, and the heparanase activity is strongly implicated in the structural remodeling of the extracellular GAG matrix, potentially leading to tumour cell invasion. Polymer–protein/peptide conjugates are one of the most promising approaches for anticancer therapy due to their controllability, biocompatibility, and targeting properties. In this study, distinct and well-defined glycopolymer–peptide conjugates, mimicking the multivalent architecture found in GAGs, were synthesised for targeting and killing tumour cells. Regio-selectively sulphated galactosamine derivatives were chemically synthesised, and six GAGs-mimetic glycopolymers were generated by post-modification based on the ring-opening metathesis polymerization (ROMP). The glycopolymers with diverse galactosamine sulphation patterns showed significant inhibitory effects on heparanase. Glycopolymers decorated with 3,4,6-O-sulphated GalNAc exhibited the highest activities, inhibiting heparanase as well as tumour cell proliferation. We demonstrated that a novel glycopeptide mimetic, derived from end-functionalised conjugation of the iRGD peptide on the glycopolymer, could effectively enter HeLa cells and inhibit signalling pathways involved in tumour cell proliferation. These findings should promote the development of novel glycomimetics for specific tumour-targeted therapies.

This paper presents a simple and reliable routine for batch fabrication of wear-resistant and conductive probe with a PtSi tip. The fabrication process is based on inductively coupled plasma (ICP) etching, metal evaporation, and annealing. Si tips with curvature radii less than 10 nm were produced with good wafer-level uniformity using isotropic etching and thermal oxygen sharpening. The surface roughness of the etched tip post was reduced by optimized isotropic etching. The dependence of the platinum silicide morphology on annealing conditions were also systematically investigated, and conductive and wear-resistant probes with PtSi tips of curvature radii less than 30 nm were batch fabricated and applied for scanning piezoelectric samples.

Heparan sulfate (HS) is a sulfated polysaccharide presenting on the animal cell surface and in the extracellular matrix that plays a critical role in a range of different biological processes. The receptor for advanced glycation end-products (RAGE), as a major receptor linked to numerous diseases, can interact with HS to activate signaling of RAGE ligands in the disease process. We herein report a concise chemoenzymatic approach for the synthesis of HS-mimetic glycopolymers as RAGE antagonists. Glycopolymer with GlcA units was chemically synthesized and subsequently modified by enzymatic elongation and chemical sulfation. Six HS-mimetic glycopolymers with pendant sulfated di-, tri-, or tetrasaccharides were successfully prepared for evaluation of their interaction with RAGE. Upon evaluation, the HS-mimetic glycopolymer decorated with overall sulfated trisaccharides was determined to have the highest binding affinity with RAGE. These findings would promote the further exploration of HS-RAGE interactions and the development of RAGE antagonists.

Novel microporous carbon materials (DCMC) with excellent electron conductivity and ultrahigh surface area (1896.9 m 2 g −1 ) are successfully prepared from discarded clothes. The porous carbon-encapsulated sulfur composites were synthesized by a feasible melting process and used as host materials for lithium sulfur batteries. Because of the unique microporous, ultrahigh surface area and irregular wrinkled surface coexisting structure, the resulting microporous carbon/sulfur (DCMC/S) composite cathode possesses a good rate capability and long-term cycling performance. The initial discharge capacity of the DCMC2/S composite electrode with 74.3 wt% sulfur content is 1082.6 mAh g −1 at a current rate of 0.2 C. At a higher current rate of 1 C, it possesses excellent cyclic performance and retained a capacity of 422.8 mAh g −1 after 500 cycles with a low capacity fading rate of 0.11% per cycle. The coulombic efficiency remains over 98% during cycling.

This work reports a batch fabrication process for silicon nanometer tip based on isotropic inductively coupled plasma (ICP) etching technology. The silicon tips with nanometer apex and small surface roughness are produced at wafer-level with good etching homogeneity and repeatability. An ICP etching routine is developed to make silicon tips with apex radius less than 5 nm, aspect ratio greater than 5 at a tip height of 200 nm, and tip height more than 10 &mu, m, and high fabrication yield is achieved by mask compensation and precisely controlling lateral etch depth, which is significant for large-scale manufacturing.

Aldehyde oxidase (AOX) is a drug metabolizing molybdo-flavoenzyme that has gained increasing attention because of contribution to the biotransformation in phase I metabolism of xenobiotics. Unfortunately, the intra- and interspecies variations in AOX activity and lack of reliable and predictive animal models make evaluation of AOX-catalyzed metabolism prone to be misleading. In this study, we developed an improved computational model integrating both atom-level and molecule-level features to predict whether a drug-like molecule is a potential human AOX (hAOX) substrate and to identify the corresponding sites of metabolism. Additionally, we combined the proposed computational strategy and in vitro experiments for evaluating the metabolic property of a series of epigenetic-related drug candidates still in the early stage of development. In summary, this study provides an improved strategy to evaluate the liability of molecules toward hAOX and offers useful information for accelerating the drug design and optimization stage.

Eukaryotic filamentous yellow-green algae from the Tribonema genus are considered to be excellent candidates for biofuels and value-added products, owing to their ability to grow under autotrophic, mixotrophic, and heterotrophic conditions and synthesize large amounts of fatty acids, especially unsaturated fatty acids. To elucidate the molecular mechanism of fatty acids and/or establish the organism as a model strain, the development of genetic methods is important. Towards this goal, here, we constructed a genetic transformation method to introduce exogenous genes for the first time into the eukaryotic filamentous alga Tribonema minus via particle bombardment. In this study, we constructed pSimple-tub-eGFP and pEASY-tub-nptⅡ plasmids in which the green fluorescence protein (eGFP) gene and the neomycin phosphotransferase Ⅱ-encoding G418-resistant gene (nptⅡ) were flanked by the T. minus-derived tubulin gene (tub) promoter and terminator, respectively. The two plasmids were introduced into T. minus cells through particle-gun bombardment under various test conditions. By combining agar and liquid selecting methods to exclude the pseudotransformants under long-term antibiotic treatment, plasmids pSimple-tub-eGFP and pEASY-tub- nptⅡ were successfully transformed into the genome of T. minus, which was verified using green fluorescence detection and the polymerase chain reaction, respectively. These results suggest new possibilities for efficient genetic engineering of T. minus for future genetic improvement.

In this letter, we report an approach to the stereoselective α-glycosylation of l-fucose that is exemplified by effect of anomeric configuration. The neighboring group participation is not compatible with α-glycosylation of l-fucose, therefore the remote participation by 4-O-Bz was employed to control the formation of 1,2-cis-glycosidic bond. Furthermore, we found the anomeric configuration of fucose donor is crucial to stereoselectivity of the glycosylated products. The α/β-mixed products were generated by using β-anomeric donor while the glycosyl donor in α configuration yielded products in high α-selectivity possibly due to the distinct pathway to forming the key intermediates. This phenomenon supplies the basis for the synthesis of complicated natural carbohydrates containing fucose α-glycoside, such as fucoidans, fucosylated N-glycans, and fucosylated chondroitin sulfates, etc.

As the most important method to prepare pharmaceutical and chemical intermediate aromatic ketones, Friedel–Crafts (F–C) acylation is used to seek a novel catalytic system which is imminently consistent with the concept of green chemistry. In this study, six deep eutectic solvents (DES) were synthesized for the Friedel–Crafts acylation reaction as a catalytic solvent. Among the six DES, choline chloride-zinc chloride ([ChCl][ZnCl2]2) proved to be the most competent candidate of electron-rich arenes with acylation reagent. It got the highest yield when 1.0 equivalent of [ChCl][ZnCl2]2 used with acyl halides at 70 °C. Recycled DES was reused directly without any extra process. After five cycles, the catalytic activity did not decrease significantly (80–85%). Finally, according to experimental validation, the possible mechanism of this reaction was considered.

The photochemical reaction process of 4-methyl-7-hydroxycoumarin (7H4MC) was studied by UV-Vis spectrometer and fluorescence spectroscopy. The results have shown that the characteristic peak of the UV-Vis spectra at 323 nm of 7H4MC undergoes a significant decrease in absorbance and a slight blue shift when was illuminated; the absorbance of the absorption peak at 279 nm rises, and there is a tendency for new peaks to appear. May be, there are structural changes or new materials generation. The addition of imidazole, VC, 3-indole methanol, GSH and other substances also have different effects on the photochemical reaction of 7H4MC. Among them, only imidazole has a certain inhibitory effect on the process of its photochemical reaction.

A novel microcantilever sensor was batch fabricated for Yersinia detection. The microcantilever surface modification method was optimized by introducing a secondary antibody to increase the number of binding sites. A novel microfluidic platform was designed and fabricated successfully. A 30 &mu, L solution could fully react with the microcantilever surface. Those routines enhanced the binding efficiency between the target and receptor on the microcantilever. With this novel designed microfluidic platform, the specific adsorption of 107 Yersinia on the beam surface with modified F1 antibody was significantly enhanced.

This work reported a microcantilever biosensor based on gold nanoparticles (AuNPs) amplification, which is applied to detect the protein biomarker Alpha fetoprotein (AFP) with high sensitivity. The detection limit of the AuNPs amplified biosensor is 21 pg/mL, about 70 times of magnitude smaller than that without AuNPs amplification. Linear dependence of the relative frequency shift on the AFP concentration between 0 ng/mL and 70 ng/mL were achieved. the sensitivity was dramatically enhanced from 7.68 Hz/nM to 412 Hz/nM by the signal amplification immunoassay, and the good detection reproducibility was obtained.

Edible Sonchus oleraceus Linn is a medicinal plant with many bioactivities such as anti-diabetic activity and anti-inflammatory activity. However, the main bioactive components such as polyphenols in S. oleraceus Linn are poorly absorbed in gastrointestinal tract and rapidly metabolized. Thereby, a self-emulsifying delivery system containing S. oleraceus Linn extracts (SSEDDS) was introduced to evade these problems. Herein, the anti-inflammatory effect of SSEDDS on streptozotocin-induced diabetic rats was investigated. The plasma glucose level was increased and plasma insulin level was decreased in diabetic rats. The levels of NF-κB, TNF-α, and IL-6 in the liver were significantly improved in diabetic rats (p 0.05). Conversely, daily fed diabetic rats with 100, 200 and 400 mg/kg/day of SSEDS and 1 mg/kg/day metformin for 4 weeks, significantly (p 0.05) restored all the above mentioned parameters to near normal levels. The immuno-histochemical studies confirmed the anti-inflammatory effects of SSEDDS.

Indoleamine 2,3-dioxygenase 1 (IDO1) is an intracellular monomeric heme-containing enzyme that catalyzes the first and the rate limiting step in catabolism of tryptophan via the kynurenine (KYN) pathway, which plays a significant role in the proliferation and differentiation of T cells. IDO1 has been proven to be an attractive target for anticancer therapy and chronic viral infections. In the present study, a class of IDO1 inhibitors with novel scaffolds were identified by virtual screening and biochemical validation, in which the compound DC-I028 shows moderate IDO1 inhibitory activity with an IC50 of 21.61 μM on enzymatic level and 89.11 μM on HeLa cell. In the following hit expansion stage, DC-I02806, an analog of DC-I028, showed better inhibitory activity with IC50 about 18 μM on both enzymatic level and cellular level. The structure–activity relationship (SAR) of DC-I028 and its analogs was then discussed based on the molecular docking result. The novel IDO1 inhibitors of DC-I028 and its analogs may provide useful clues for IDO1 inhibitor development.

In this work, we fabricate a ternary nanocomposite photoelectrode consisting of TiO2 nanoparticles, polyoxometalate (P2W18) and copper quantum dots (Cu QDs) so as to create a synergistic effect of the ternary nanocomposite on photovoltaic and photoelectrocatalytic performances. Both the high electron mobility from low cost Cu QDs and the high electro-hole separation efficiency from P2W18 could evidently improve the photoelectrochemical performance of TiO2. Transient photocurrent and current-voltage curves measurements demonstrate that both the photocurrent response and power conversion efficiency of the P2W18/Cu/TiO2 film were markedly enhanced in comparison with that of the only TiO2 film and the P2W18/TiO2 film, respectively. Furthermore, the photoelectrode also exhibited significant photoelectrocatalytic activity for formic acid oxidation. The substitute of copper quantum dots for noble metals in electrode is a favorable innovation for the practical application of photoelectrochemical devices.

To explore the synergistic effects of polyoxometalate and noble metal nanoparticles on the photovoltaic performance of titanium dioxide (TiO2), multilayer film photoanodes consisting of TiO2 nanoparticles, gold nanoparticles (Au) and Dawson-type polyoxometalate K6P2W18O62 (abbr. as P2W18) have been prepared by the layer-by-layer self-assembly method, and poly(styrenesulfonate) (PSS) was used as a film forming auxiliary material. These film electrodes were characterized by UV-vis spectra, X-ray photoelectron spectroscopy, atomic force microscopy, and photoelectrochemical measurements. Transient photocurrent and current–voltage curve measurements demonstrate that the photocurrent response and power conversion efficiency increase in the sequence: the TiO2 film < the P2W18/TiO2 film < the TiO2/P2W18/Au film. These results provide valuable information for photovoltaic and photoelectrochemical applications.