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In this work, the Metal-rich phase Chromium Aluminum (CrAl)/Ceramic phase Chromium Aluminum Nitride (CrAlN) multi-layer coatings were prepared by Arc Ion Plating (AIP). The micro-structure and phase composition of CrAl/CrAlN multi-layer coatings were characterized, and the microstructure, mechanical properties, residual stress and fracture toughness of the coating were emphatically analyzed. It has been found out that the residual stress of the multi-layer coating was only −0.932 ± 0.065 GPa, which was significantly lower than that of the mono-layer coating for −1.569 ± 0.093 GPa. At the same time, it was also found that the preferred growth orientation of the coating changed from a mono-layer (111) to a multi-layer (200) crystal plane. The hardness of the multi-layer (22.74 ± 0.57 GPa) is slightly lower than that of the mono-layer (24.92 ± 0.5 GPa), and the adhesion strength (46.2 ± 3.8 N) is obviously higher than that of the mono-layer (37.4 ± 2.4 N), and the fracture toughness is also higher (8.7 ± 0.8 MPa m1/2). In addition, the mechanism of crack initiation and propagation in stress-induced coatings was studied in detail on the basis of the structure of micro-nano CrAl/CrAlN multi-layer coatings.

Development of conceptually novel and practically useful bioconjugation reactions has been an intense pursuit of chemical biology research. Herein, we report an unprecedented bioconjugation reaction that hinges on a chemical trigger-enabled inverse-electron-demand Diels–Alder (IEDDA) cycloaddition of trans-cycloheptene (TCH) with tetrazine. Unlike the conventional strain-promoted bioconjugation reactions that utilize built-in strained alkenes as reactants, the current one features a “trigger-release-conjugate” reaction model, in which a highly strained TCH species is released from a bench-stable bicyclic N-nitrosourea (BNU) derivative upon treatment with an external stimulus. It is noteworthy that the reactivity–stability balance of BNU derivatives could be tuned by manipulating their N-1 substituents. As a proof-of-concept case, this new chemical trigger-enabled IEDDA reaction has been applied to in vitro protein labeling and pretargeted cell imaging. This work opens a new avenue to utilize BNU derivatives as a new class of chemical reporters in bioconjugate chemistry.

Anaerobic digestion of cattle manure has a low efficiency due to the high hydraulic retention time (HRT) required to degrade the abundant degradation-resistant compositions, co-digestion with food waste is effective at improving the methane production. Lowering the HRT can therefore increase the methanogenic efficiency during co-digestion. This study considered the effects of different HRTs (25, 20, 15, 10, 7, 5, and 4 days) on cattle manure and food waste co-digestion. The highest methane production was achieved at 1.48 L/L/d with an HRT of 5 days. The maximum methane yields (236–257 mL/g-VS) were attained at HRT ≥15 days and decreasing the HRT to 10-5 days resulted in low methane yields and complete process failure at HRT 4 days, due to volatile fatty acids accumulated and microorganisms washed out. From a high HRT of 20 days to a low HRTs of 5 days, Bacteroidetes and Firmicutes were the dominant bacteria and the percentage of syntrophic acetate oxidizing bacteria (mainly Pelotomaculum and Pseudothermotoga) clearly increased. The dominant methanogen changed from the acetotrophic Methanosaeta to the hydrogenophilic Methanobrevibacter. These results enable biogas plants to utilize surplus amounts of cow manure and food waste in a sustainable manner with high process capacity and methane recovery.

An unprecedented photoinduced azide–alkene cycloaddition has been developed, the key elements of which include the photoisomerization of cis-cycloheptenone to trans-cycloheptenone, strain-promoted 1,3-dipolar cycloaddition of trans-cycloheptenone with azide, and aerobic oxidative aromatization of the resulting 1,2,3-triazoline. The newly developed photoclick reactions display several appealing features including high overall efficiency, broad substrate scope, environmentally benign conditions, and operational simplicity, which provide an enabling tool for accessing structurally diverse 1,2,3-triazoles. In addition, the photoisomerization–cycloaddition strategy could also be extended to the 1,3-dipolar cycloadditions of trans-cyclooctenone with azide and trans-cycloheptenone with nitrile oxide. More appealingly, the title reaction has been successfully applied as a bioconjugation tool for in vitro protein labeling.

Plakortin-type polyketides represent a growing family of sponge-derived marine natural products that display notable structural and biological diversity. In particular, a series of polycyclic plakortin polyketides, namely hippolachnin A and gracilioethers, have been identified in recent years, which attract immense interest from the synthetic community owing to their unique molecular architectures and promising biomedical potential. A number of elegant total syntheses of these targets and some synthetic studies have been performed through either bio-inspired or rationally designed strategies. This focused review aims to provide an up-to-date summary of the progress in the chemical synthesis of plakortin polyketides, with an emphasis on the key synthetic elements enabling the rapid assembly of their core skeletons.

Binge alcohol drinking is fast becoming a global health concern, with the liver among the first organ involved and the one afflicted with the greatest degree of injury. Oxidative stress, alterations in hepatic metabolism, immunity and inflammation have all been reported to contribute to the development of alcoholic liver disease (ALD). Hydrogen gas (H2) serves a key role in the modulation of hepatic redox, immune and inflammatory homeostasis. However, the effects of treatment using intraperitoneal injection of H2 on ALD remain unexplored. Therefore, the aim of the present study was to investigate the effects and underlying mechanism of intraperitoneal injection of H2 on acute alcohol-induced liver injury in a mouse model. H2 was administered by daily intraperitoneal injections (1.0 ml/100 g) for 4 days. On day 4, the mice received H2 after fasting for 5.5 h. After 30 min, the mice were administered with 33% (v/v) ethanol at a cumulative dose of 4.5 g/kg body weight by four equally divided gavages at 20-min intervals. Blood and liver tissues were collected at 16 h after the first ethanol gavage. Subsequently, serum alanine aminotransferase (ALT), aspartate aminotransferase (AST), triglyceride and total cholesterol (TC) levels were analyzed using an Automatic Clinical Analyzer. Hepatic JNK activity and GAPDH levels were examined by western blotting. It was observed that acute ethanol gavage induced liver injury, as indicated by significantly increased serum ALT and AST levels, which were effectively decreased by H2 at 16 h after the first ethanol gavage. In addition, H2 treatment reduced serum TC levels in the Alcohol+H2 group when compared with those in Alcohol group. Mechanistically, H2 attenuated hepatic JNK phosphorylation induced by acute ethanol gavage. Therefore, the results of the present study demonstrated that treatment with exogenous H2 by intraperitoneal injection may alleviate acute alcohol-induced liver injury by inhibiting hepatic JNK activation, which may represent a novel therapeutic strategy for ALD.

Background. Nonalcoholic fatty liver disease (NAFLD) has high global prevalence; however, the treatments of NAFLD are limited due to lack of approved drugs.Methods. Mice were randomly assigned into three groups: Control group, NAFLD group, NAFLD plus Si-Wu-Tang group. A NAFLD mice model was established by feeding with a methionine- and choline-deficient (MCD) diet for four weeks. Si-Wu-Tang was given orally by gastric gavage at the beginning of 3rd week, and it lasted for two weeks. The treatment effects of Si-Wu-Tang were confirmed by examining the change of body weight, serum alanine aminotransferase (ALT) and aspartate transaminase (AST) levels, Oil Red O staining, and hematoxylin and eosin (H&E) staining of the liver samples and accompanied by steatosis grade scores. The expression and activation of the possible signaling proteins involved in the pathogenesis of NAFLD were determined by western blotting.Results. Mice fed with four weeks of MCD diet displayed elevated serum levels of ALT and AST, while there was decreased body weight. The hepatic Oil Red O staining and H&E staining showed severe liver steatosis with high steatosis grade scores. All these can be improved by treating with Si-Wu-Tang for two weeks. Mechanistically, the increased hepatic TLR4 expression and its downstream JNK phosphorylation induced by MCD diet were suppressed by Si-Wu-Tang. Moreover, the upregulations of Caspase-8, gasdermin D (GSDMD), and cleaved-GSDMD in liver mediated by MCD diet were all inhibited by Si-Wu-Tang.Conclusions. Treatment with Si-Wu-Tang improves MCD diet-induced NAFLD in part via blocking TLR4-JNK and Caspase-8-GSDMD signaling pathways, suggesting that Si-Wu-Tang has potential for clinical application in treating NAFLD.

Infrared (IR) imaging is one of the significant tools for the quality control measurements of fabricated samples. Standard IR imaging techniques use direct measurements, where light sources and detectors operate at IR range. Due to the limited choices of IR light sources or detectors, challenges in reaching specific IR wavelengths may arise. In our work, we perform indirect IR microscopy based on the quantum imaging technique. This method allows us to probe the sample with IR light, while the detection is shifted into the visible or near-IR range. Thus, we demonstrate IR quantum imaging of the silicon chips at different magnifications, wherein a sample is probed at 1550 nm wavelength, but the detection is performed at 810 nm. We also analyze the possible measurement conditions of the technique and estimate the time needed to perform quality control checks of samples., Comment: Submitted for publication

Basic and clinical studies have shown that hydrogen (H2), the lightest gas in the air, has significant biological effects of anti-oxidation, anti-inflammation, and anti-apoptosis. The mammalian cells have no abilities to produce H2 due to lack of the expression of hydrogenase. The endogenous H2 in human body is mainly produced by anaerobic bacteria, such as Firmicutes and Bacteroides, in gut and other organs through the reversible oxidation reaction of 2 H+ + 2 e- ⇌ H2. Supplement of exogenous H2 can improve many kinds of liver injuries, modulate glucose and lipids metabolism in animal models or in human beings. Moreover, hepatic glycogen has strong ability to accumulate H2, thus, among the organs examined, liver has the highest concentration of H2 after supplement of exogenous H2 by various strategies in vivo. The inadequate production of endogenous H2 play essential roles in brain, heart, and liver disorders, while enhanced endogenous H2 production may improve hepatitis, hepatic ischemia and reperfusion injury, liver regeneration, and hepatic steatosis. Therefore, the endogenous H2 may play essential roles in maintaining liver homeostasis.

Faraday pseudocapacitors take both advantages of secondary battery with high energy density and supercapacitors with high power density, and electrode material is the key to determine the performance of Faraday pseudocapacitors. Transition metal oxides and nitrides, as the two main kinds of pseudocapacitor electrode materials, can enhance energy density while maintaining high power capability. Recent advances in designing nanostructured architectures and preparing composites with high specific surface areas based on transition metal oxides and nitrides, including ruthenium oxides, nickel oxides, manganese oxides, vanadium oxides, cobalt oxides, iridium oxides, titanium nitrides, vanadium nitrides, molybdenum nitrides and niobium nitrides, are addressed, which would provide important significances for deep researches on pseudocapacitor electrode materials.

Graphene/RuO2/Co3O4 (GRC) nanocomposites, synthesized using a one-step facile and efficient hydrothermal method, have been investigated as advanced electrodes for supercapacitors. The physical properties of the GRC nanocomposites were characterized by scanning electron microscopy, transmission electron microscopy and X-ray diffraction. Furthermore, the electrochemical properties were tested using an electrochemical workstation with a three-electrode system. Graphene acted as an excellent conductive substrate to provide an ultra-high specific surface area for contact with the electrolyte. The metal oxide particles (diameter

A novel BODIPY-RhB ratiometric fluorescent probe 1 for Hg2+ based on a fluorescence resonance energy transfer mechanism has been developed. In this system, the energy transfer efficiency is 94.8%. The BODIPY-RhB probe 1 can detect Hg2+ ions with a very low detection limit of 1.56 ppb, and very high selectivity toward Hg2+ ions.

A modular synthesis of merochlorins A and B, two naturally occurring antibiotics, has been achieved concisely from readily available building blocks in 4-6 steps. The key steps include the bio-inspired tandem phenol oxidative dearomatization/[5 + 2] and [3 + 2] cycloadditions to construct the tricyclic cores of the targets, and the intermolecular Diels-Alder reaction followed by dehydrogenative aromatization to assemble the remaining aromatic units. The antibacterial activities of merochlorins A, B and some advanced synthetic intermediates were also evaluated, which provided valuable information on the structure-activity relationship (SAR) of this class of new antibiotics.

Ethnopharmacological relevance Yin Yang Gong Ji pill (YYGJ) is a formula that was used in the Ming Dynasty. This study investigated the effects of YYGJ on HepG2 and MHCC97H hepatoma cells. Material and methods The effects of YYGJ drug-containing rat serum (YYGJ serum) on cell proliferation and the cell cycle were investigated by a tetrazolium dye-based MTS assay and flow cytometry. Apoptosis was assayed by TUNEL and flow cytometry. E-cadherin, vimentin, c-Myc, Smad4, and MMP2 expression were assayed by real-time quantitative PCR and Western blot assays. The effects on cell invasiveness and migration were evaluated by wound healing and transwell assays. The antitumor activity of 10% YYGJ serum was compared to that of blank control, 10% rat serum control and 5-fluorouracil(FU). Results HepG2 and MHCC97H cell proliferation was inhibited by YYGJ serum in a time- and concentration-dependent manner. Cells accumulated in G0/G1 and apoptosis was increased in both cell lines by 10% YYGJ serum. The effects of apoptosis in 10% YYGJ serum were weaker than those in response to 5-FU. E-cadherin and Smad4 expression were upregulated by 10% YYGJ serum, but c-Myc, vimentin and MMP2 expression were downregulated in both hepatoma cell lines. The protein expression of Smad4 in HepG2, and mRNA expression of MMP2 and E-cadherin in both cell lines had no difference between 10% YYGJ serum and 5-FU treated groups. Cell invasion and migration were decreased by 10%YYGJ serum while cell cytotoxicity was shown in 5-FU treated group. Conclusions YYGJ drug-containing serum inhibited HepG2 and MHCC97H cell proliferation, induced apoptosis, and regulated the expression of tumor-related genes and proteins. It reduced tumor cell invasion and migration. Further study to investigate the antitumor activity of YYGJ is warranted.

The damages resulting from frost heaving are the main causes of channel destruction in seasonal frozen soil regions. Over the years, many experimental studies have been performed regarding the channel anti-frost heaving in the Hetao irrigation area. However, there have been few experimental research studies conducted regarding the insulation and anti-frost heave effects of polystyrene boards (EPS) of different thicknesses. Therefore, in order to explore the insulation mechanism and anti-frost heave effects of precast EPS laid under the conditions of different thicknesses, an anti-frost heave test field was established in the Hetao irrigation area for the examination of the ground temperatures, frozen depths, frost heave amounts, and water content change rules. This study&rsquo, s results showed that, for the laid EPS with thicknesses between 2 and 12 cm, the frost-heave reduction rate ranged from 53.2% to 92.6%, total accumulated temperature warming ranged from 248.65% to 565.93%, and the frozen depth reduction rate was between 59.8% and 75.9%. It was determined that the EPS per cm additions could effectively improve the ground temperatures at a buried depth of 30 cm by 0.78 &deg, C, and reduce the frozen depth by 10.1 cm. Then, by comprehensively considering the positive economic and insulation effects, it was determined that the most appropriate thickness of the EPS laid under the precast concrete slabs in the Hetao irrigation area of Inner Mongolia was 8&ndash, 10 cm.

Diethylnitrosamine (DEN) is present in food, water, and daily supplies and is regarded as a toxicant of carcinogenicity. The developmental toxicity of DEN has been rarely reported as yet. In this study, zebrafish were exposed to different concentrations of DEN at 6 h post-fertilization (hpf) to access embryonic toxicity of the compound. The results show that DEN resulted in negative effects of hatching rate, heartbeat, body length, and spontaneous movement. Deformities, including notochord malformation, pericardium edema, embryonic membrane turbidity, tail hypoplasia, yolk sac deformity, and growth retardation, happened during exposure period. Moreover, production of reactive oxygen species (ROS) significantly increased after DEN treatment. Then, alterations of the expression level of oxidative stress-related genes were observed in our results. To our knowledge, this is the first study concerning the effect of DEN on zebrafish. And from the information of our research, we speculated that development toxicity of DEN should be related to the excessive oxidative stress.

Zygosaccharomyces rouxii is an important microorganism for aroma production in traditional fermented foods. Using Z. rouxii as the original strain, the batch was split after glucose depletion in the culture medium. Half of the volume of the culture medium was released, and fresh culture medium was fed in. The exponential culture kinetics and the formula for the half‐fractional fed‐batch cultivations were determined to achieve a new strategy for high cell density culturing of Z. rouxii. Based on a full cultivation, three half‐fractional fed‐batch cultivations were performed after every 10 hr of culture. The specific growth rates of Z. rouxii at the different stages were in the order μX0>μX1>μX2>μX3 (0.525 to 0.229 hr−1). The glucose substrate consumption rates gradually decreased following the order μS0>μS1>μS2>μS3 (−1.165 to −0.722, g/g). The equation models for cell growth and glucose substrate consumption showed typical exponential behavior. The total cell yield was 1.78‐fold higher than the yield from a full cultivation, and this continuous subculture strategy also indicated a higher efficiency than traditional full cultivation. A new strategy for highly efficient culturing of Z. rouxii was achieved in a pilot scale. A foundation with data support for the production and application of Z. rouxii was developed.

In this work, a label-free DNAzyme biosensor was proposed for the detection of oligonucleotides related to a hepatitis B virus (HBV) DNA segment. The novel DNAzyme biosensor was based on the electrochemical reduction of graphene oxide–carboxyl multi-walled carbon nanotube composites (GO–CMWCNTs) and the electrodeposition of gold nanoparticles (AuNPs) on a glassy carbon electrode (GCE). The thiolate hairpin capture probes with a caged G-quadruplex configuration were self-assembled on AuNPs through the well-known Au–thiol binding. Only after hybridization with target DNA, the hairpin configuration could be opened and released the particular guanine-rich nucleic acid sequences which could assemble to G-quadruplexes. In the presence of hemin and K+, the hemin/G-quadruplex DNAzyme was generated on the electrode surface, triggering the electrochemical H2O2-mediated oxidation of 3,3′,5,5′-tetramethylbenzidine (TMB). With the advantages of amplification effects of AuNPs and hemin/G-quadruplex, a linear concentration range from 10 pM to 10 nM with a limit of detection of 0.5 pM was obtained for the target DNA. This method exhibited excellent discrimination of target DNA from one or two-base mismatched DNA and non-complementary DNA sequences. In addition, the proposed biosensor was successfully applied to the determination of target DNA in human serum samples.

This work reports on a novel fluorescent sensor 1 for Cd2+ ion based on the fluorophore of tetramethyl substituted bis(difluoroboron)-1,2-bis[(1H-pyrrol-2-yl)methylene]hydrazine (Me4BOPHY), which is modified with an electron donor moiety of N,N-bis(pyridin-2-ylmethyl)benzenamine. Sensor 1 has absorption and emission in visible region, at 550 nm and 675 nm, respectively. The long wavelength spectral response makes it easier to fabricate the fluorescence detector. The sensor mechanism is based on the tunable internal charge transfer (ICT) transition of molecule 1. Binding of Cd2+ ion quenches the ICT transition, but turns on the π − π transition of the fluorophore, thus enabling ratiometric fluorescence sensing. The limit of detection (LOD) was projected down to 0.77 ppb, which is far below the safety value (3 ppb) set for drinking water by World Health Organization. The sensor also demonstrates a high selectivity towards Cd2+ in comparison to other interferent metal ions.

Petrographic features, C, O, S, and Sr isotopes were determined, and fluid inclusions (FI) were analyzed on various stages of vug- and fracture-fillings from the Cambrian and Lower Ordovician reservoirs in the Tazhong area, Tarim basin, NW China. The aim was to assess the origin of pyrite and anhydrite and the processes affecting sulfur during diagenesis of the carbonates. Pyrite from seven wells has δ34S values from −22‰ to +31‰. The pyrites with low δ34S values from −21.8‰ to −12.3‰ were found close to fracture-filling calcites with vapor-liquid double-phase aqueous fluid inclusions homogenization temperatures (FI-Th) from 55.7 to 73.2°C, salinities from 1.4wt% to 6.59wt% NaCl equiv and δ13C values from −2.3‰ to −14.2‰, indicating an origin from bacterial sulfate reduction by organic matter. Other sulfides with heavier δ34S values may have formed by thermochemical sulfate reduction (TSR) during two episodes. The earlier TSR in the Middle and Lower Cambrian resulted in pyrites and H2S having δ34S values from 30 to 33‰, close to those of bedded anhydrite and oilfield water (approximately 34‰). The later TSR is represented by calcites with δ13C values as light as −17.7‰ and FI-Th of about 120–145°C, and pyrite and H2S with δ34S values close to those of the Upper Cambrian burial-diagenetic anhydrite (between +14.8‰ and +22.6‰). The values of the anhydrite are significantly lighter than contemporary seawater sulfates. This together with 87Sr/86Sr values of anhydrite and TSR calcites from 0.7091 to 0.7125 suggests a source from the underlying Ediacaran seawater sulfate and detrital Sr contribution.

A novel fluorescent Probe 1, based on phenanthro-imidazole has been developed as an efficient chemosensor for the trace detection of copper ions (Cu2+). Probe 1 demonstrated sensitive fluorescence quenching upon binding with Cu2+ through 1:1 stoichiometric chelation. The detection limit for Cu2+ ions was projected through linear quenching fitting to be as low as 2.77 × 10−8 M (or 1.77 ppb). The sensing response was highly selective towards Cu2+ with minimal influence from other common metal ions, facilitating the practical application of Probe 1 in trace detection.

We investigate the natural gas flow behavior in the Dengying carbonate reservoir of Gaoshiti-Moxi Block in China. Outcrops observation, petrophysical properties measurement, and formation micro-resistivity image logging (FMI) all show that the vugs distribute in a stratified manner with characteristic length ranging from 0.2 to 4 cm. The horizontal permeability is significantly larger than the vertical permeability due to the stratified distribution of vugs and fractures. We build a representative conceptual reservoir model to describe this fracture-vuggy type carbonate reservoir. Both Darcy equation and Stokes-Brinkman equation are applied to simulate natural gas flow in this type of reservoir. Simulation results show that natural gas mainly flows along the free channel formed by low-dip fractures and flat ellipsoid vugs. Compared with the Darcy method, the Stokes-Brinkman method provides a more accurate prediction of gas flow behavior in the fracture-vug carbonate reservoir.

Sphingosine kinase 1 (SphK1) pathway is critical in the pathogenesis of diabetic nephropathy. Recently, we found that berberine suppressed the activation of SphK1 pathway in diabetic kidney, protecting against diabetic nephropathy. The potential molecular mechanism, however, is still unknown. Here, we showed that berberine prevented the expression of α-smooth muscle actin (α-SMA), transforming growth factor-β1 (TGF-β1) and fibronectin (FN) in mesangial cells cultured by high glucose. Furthermore, berberine suppressed the activation of SphK1 pathway via inhibition of the activity and expression of SphK1 in mesangial cells cultured by high glucose. Surprisingly, berberine blocked the increased activity and expression of SphK1 in mesangial cells transfected by wild type SphK1 under normal glucose condition. However, berberine had no inhibitory effect on the recombinant human SphK1 protein. Finally, berberine markedly attenuated the high glucose-induced activator protein-1 (AP-1) activity in mesangial cells. Altogether, these data not only demonstrate that berberine is an important agent against diabetic nephropathy through inhibition of SphK1/AP-1 pathway, but also indicate that the inhibition of SphK1/AP-1 by berberine is independent of ambient glucose concentration.

A generic and effective approach to “switch on” and enhance the two-photon fluorescence (TPF) emission of quenched TPF molecules, i.e., fluorene derivatives, is reported in terms of molecular recognition with a decoupling medium. Such a medium, in this case Bombyx mori silk, can recognize TPF molecules and inhibit the aggregation of the TPF molecules. The designed TPF molecules are 2,7-bis[2-(4-nitrophenyl)ethenyl]-9,9-dibutylfluorene (4NF) and 2,7-bis[2-(4-nitrophenyl)ethenyl]-9,9-dioctylfluorene (8NF), which exhibit suppressed TPF emission owing to molecular-stacking-led aggregation in the solid form. Due to the specific recognition between –NO2 in the quenched fluorescent molecules and –NH groups in silk fibroin molecules, the aggregated molecules of 4NF/8NF molecules are decoupled. This decoupling gives rise to a significant increase in TPF quantum yields. The mechanism is further confirmed by replacing the terminal group –NO2 in 8NF with –CH3 (in 2,7-bis[2-(4-methylphenyl)ethenyl]-9,9-dioctylfluorene; 8MF) to eliminate the possibility of molecular recognition. As predicted, in the case of 8MF the switching-on effect is eliminated. Completely new TPF silk fibers can additionally be applied in real-time 3D high-resolution TPF scaffold bioimaging.

We present a quantum perturbation theory on two-photon absorption (2PA) in monolayer and bilayer graphene which is Bernal-stacked. The theory shows that 2PA is significantly greater in bilayer graphene than monolayer graphene in the visible and infrared spectrum (up to 3 μm) with a resonant 2PA coefficient of up to ∼0.2 cm/W located at half of the bandgap energy, γ(1) = 0.4 eV. In the visible and terahertz region, 2PA exhibits a light frequency dependence of ω(-3) in bilayer graphene, while it is proportional to ω(-4) for monolayer graphene at all photon energies. Within the same order of magnitude, the 2PA theory is in agreement with our Z-scan measurements on high-quality epitaxial bilayer graphene deposited on SiC substrate at light wavelength of 780 and 1100 nm.

On the basis of available experimental data of phase diagram and thermodynamic properties, the Sm–Zn binary system has been optimized using the CALPHAD method. The solution phases, liquid, bcc, hcp and rhombohedral, were treated as by substitutional solutions models, while the intermediate compounds, SmZn, SmZn 2 , SmZn 3 , Sm 3 Zn 11 , Sm 13 Zn 58 , Sm 3 Zn 22 , Sm 2 Zn 17 and SmZn 11 , were described as stoichiometric phases. A set of self-consistent parameters capable of formulating the Gibbs energies of various phases in this binary system has obtained. Calculation based on these parameters can reproduce most of the experimental data on thermochemistry and phase diagram reported in the literatures very well are satisfactory reproduced.

The first total syntheses of rubialatins A and B, two newly discovered naphthohydroquinone dimers, were achieved with high efficiency and elegancy through rationally designed biomimetic approaches. The tandem ring contraction/Michael addition/aldol reaction followed by oxidation enabled the rapid access of prerubialatin from readily available precursors, which then diverted into rubialatins A and B via epoxidation and photoinduced skeletal rearrangement, respectively. Moreover, several new rubialatin congeners were also obtained along the synthetic tour, some of which were proved to be authentic natural products.

Total synthesis of Spirobacillene A (VI) is accomplished in 6 steps whereas for Spirobacillene B (VIII) 4 reaction steps are required.

Objectives.The study was to investigate the effects and mechanisms of Shen-Yuan-Dan (SYD) pharmacological postconditioning on myocardial ischemia/reperfusion (I/R) injury.Methods.In thein vivoexperiment, myocardial injury markers and histopathology staining were examined. In thein vitroexperiment, cell viability and cell apoptosis were, respectively, detected by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays and Hoechst 33342 fluorochrome staining. The protein expressions of Bcl-2 and Bax were determined by immunocytochemistry assay.Results.Both low and high doses of SYD protected myocardium against I/R injury in rat model by reducing lactic dehydrogenase (LDH) and creatine kinase-MB (CK-MB) activity and malondialdehyde (MDA) content, increasing superoxide dismutase (SOD) activity and attenuating histopathology injury. Meanwhile, in thein vitroexperiment, SYD promoted cell viability and inhibited the cardiomyocyte apoptosis. The level of Bcl-2 protein was restored to the normal level by SYD pharmacological postconditioning. In contrast, the Bax protein level was markedly reduced by SYD pharmacological postconditioning. These effects of SYD were inhibited by LY294002.Conclusions.The results of this study suggested that SYD pharmacological postconditioning has protective effects against myocardial I/R injury in bothin vivoandin vitromodels, which are related to activating the phosphatidylinositol 3-kinase/Akt (PI3K/Akt) pathway.

A concise biomimetic total synthesis of incarvilleatone and incarviditone is achieved in one pot via the highly stereoselective hetero- and homodimerization of (±)-rengyolone, respectively. The structure of incarviditone is revised on the basis of spectroscopic and computational evidence.

A diode-pumped doubly passively Q-switched Cr,Nd:YAG/KTP green laser with GaAs saturable absorber is realized for the first time to our knowledge. This laser can generate a more symmetric and shorter pulse when compared with the self-Q-switched Cr,Nd:YAG/KTP green laser. A symmetry factor is defined to describe the temporal symmetry of the pulses. At an incident pump power of 4.1W, a pulse symmetry factor as high as 0.995 is obtained. A rate equation model is introduced to theoretically analyze the results obtained in the experiment, in which the spatial distributions of the intracavity photon density, the pump beam and the population-inversion density are taken into account. The numerical solutions of the rate equations are in good agreement with the experimental results.

A study was conducted to determine the effectiveness of reducing the hydrogen cyanide (HCN) content of flaxseed by various processing. Flaxseed was processed by oven heating, solvent extracting, autoclaving, microwave roasting, and water boiling. The optimal parameters for each processing methods were gained. Microwave roasting of flaxseed reduced the HCN content by 82%; autoclaving flaxseed reduced its HCN content by 27%; solvent extracting once reduced HCN content by 52%, twice by 80%, and thrice by 89%; and the water boiling reduced HCN by 100%. The determination of cyanogenic glucosides in flaxseed was performed by “picrate method” presented by Dr Howard Bradbury and colorimetric method promulgated by AOAC (Association of Official Agricultural Chemists).

We report an experimental study on the dynamic thermomagnetic (TM) reversal mechanisms at around Curie temperature (Tc) for isolated 60 nm pitch single-domain [Co/Pd] islands heated by a 1.5 μm spot size laser pulse under an applied magnetic reversal field (Hr). Magnetic force microscopy (MFM) observations with high resolution MFM tips clearly showed randomly trapped non-switched islands within the laser irradiated spot after dynamic TM reversal process with insufficient Hr strength. This observation provides direct experimental evidence by MFM of a large magnetization switching variation due to increased thermal fluctuation/agitation over magnetization energy at the elevated temperature of around Tc. The average percentage of non-switched islands/magnetization was further found to be inversely proportional to the applied reversal field Hr for incomplete magnetization reversal when Hr is less than 13% of the island coercivity (Hc), showing an increased switching field distribution (SFD) at elevated temperature of around Tc (where main contributions to SFD broadening are from Tc distribution and stronger thermal fluctuations). Our experimental study and results provide better understanding and insight on practical heat assisted magnetic recording (HAMR) process and recording performance, including HAMR writing magnetization dynamics induced SFD as well as associated DC saturation noise that limits areal density, as were previously observed and investigated by theoretical simulations.

Pharmaceutical safety testing requires a cheap, fast and highly efficient platform for real-time evaluation of drug toxicity and secondary effects. In this study, we have developed a microfluidic system for phenotype-based evaluation of toxic and teratogenic effects of drugs using zebrafish (Danio rerio) embryos and larvae as the model organism. The microfluidic chip is composed of two independent functional units, enabling the assessment of zebrafish embryos and larvae. Each unit consists of a fluidic concentration gradient generator and a row of seven culture chambers to accommodate zebrafish. To test the accuracy of this new chip platform, we examined the toxicity and teratogenicity of an anti-asthmatic agent-aminophylline (Apl) on 210 embryos and 210 larvae (10 individuals per chamber). The effect of Apl on zebrafish embryonic development was quantitatively assessed by recording a series of physiological indicators such as heart rate, survival rate, body length and hatch rate. Most importantly, a new index called clonic convulsion rate, combined with mortality was used to evaluate the toxicities of Apl on zebrafish larvae. We found that Apl can induce deformity and cardiovascular toxicity in both zebrafish embryos and larvae. This microdevice is a multiplexed testing apparatus that allows for the examination of indexes beyond toxicity and teratogenicity at the sub-organ and cellular levels and provides a potentially cost-effective and rapid pharmaceutical safety assessment tool.

We theoretically and experimentally study excited-state absorption (ESA) induced by three-photon absorption (3PA) under the excitation of ultrafast laser pulses. Based on five-level rate-equation theory, we obtain an analytical expression for the effective four-photon absorption coefficient that originates from both singlet-singlet (S-S) and triplet-triplet (T-T) ESA. We validate that the T-T ESA could be justifiably neglected in the femtosecond regime. Experimentally, we verify it in acetone solution of 2,4,5-trimethoxychalcone by performing femtosecond Z-scan measurements; at low excitation intensity, only 3PA is determined; and under the excitation of high intensity, however, we observe the concurrence of 3PA and 3PA-induced S-S ESA processes.