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A novel palladium-catalyzed divergent decarboxylative cyclization of 2-iodobiphenyls and α-oxocarboxylic acids utilizing the atmosphere as a controlled switch is reported. Under the protection of a nitrogen atmosphere, tribenzotropones are synthesized by a [4 + 3] decarboxylative cyclization. Employing a palladium/O2 system enables a [4 + 2] decarboxylative cyclization to assemble triphenylenes. Notably, preliminary mechanistic studies indicate that the formation of triphenylenes involves a double decarboxylation.

A novel palladium-catalyzed Heck/[4 + 1] decarboxylative cyclization cascade of alkene-tethered aryl iodides with α-bromoacrylic acids is reported. This strategy employs α-bromoacrylic acids as a new C1 synthon to assemble diverse heteropolycycles, such as cyclopenta[de]isoquinolinediones and cyclopenta[de]indolo[2,1-a]isoquinolinones, in moderate to excellent yields. This reaction enables the construction of three C–C bonds via sequential fused palladacycle formation, C(vinyl)–Br bond activation and decarboxylation.

On one hand, the construction of two fused five-membered carbocyclic rings remains an extremely challenging topic in organic synthesis. On the other hand, transition-metal-catalyzed dienyne cycloaddition reactions have become one of the most powerful methods for the construction of diverse cyclic frameworks. Nevertheless, these methods are limited to noble transition-meal catalysis and non-radical cycloaddition modes. Here, a radical Smiles rearrangement strategy for allowing an unprecedented [3 + 2]/[3 + 2] carboannulation of dienynes with arylsulfonyl chlorides using cheap copper catalysis is described. This cascade method represents a novel cycloaddition mode for dienyne chemistry, which occurs by the sequence of addition of arylsulfonyl radical to a dienyne, a Smiles rearrangement and radical annulation to access cyclopenta[a]indene-fused quinolinones with excellent diastereoselectivity.

The chemoselective reaction remains a tremendous but particularly fascinating challenge in organic synthesis. Herein, we report a new domino Heck/disilylation reaction of alkene-tethered 2-(2-halophenyl)-1H-indoles with hexamethyldisilane under palladium catalysis. This procedure involving the formation of one C–C bond and two C–Si bonds proceeds efficiently through two key steps of the chemoselective Heck reaction and C–H activation by overcoming undesirable C3–H bond activation on the indoles, thus generating various disilylated tetracyclic indolo[2,1-a]isoquinolines in moderate to excellent yields. Furthermore, borylated indolo[2,1-a]isoquinolines can be produced by a Heck/borylation cascade.

A new palladium-catalyzed tandem cyclization of various alkene-tethered aryl iodides has been presented. In this protocol, o-bromobenzoic acids are employed as coupling parters to achieve the insertion of aromatic rings by the cleavage of C(sp2)-Br and decarboxylation, thus assembling various dibenzoisoquinolinediones and dibenzoisoquinolinones. In addition, a seven-membered ring can be constructed by the use of 8-bromo-1-naphthoic acid. Notably, this approach enables regioselective product formation and features broad substrate scope.

Background Sanghuangporus sanghuang is a well-known traditional medicinal mushroom associated with mulberry. Despite the properties of this mushroom being known for many years, the regulatory mechanisms of bioactive compound biosynthesis in this medicinal mushroom are still unclear. Lysine malonylation is a posttranslational modification that has many critical functions in various aspects of cell metabolism. However, at present we do not know its role in S. sanghuang. In this study, a global investigation of the lysine malonylome in S. sanghuang was therefore carried out. Results In total, 714 malonyl modification sites were matched to 255 different proteins. The analysis indicated that malonyl modifications were involved in a wide range of cellular functions and displayed a distinct subcellular localization. Bioinformatics analysis indicated that malonylated proteins were engaged in different metabolic pathways, including glyoxylate and dicarboxylate metabolism, glycolysis/gluconeogenesis, and the tricarboxylic acid (TCA) cycle. Notably, a total of 26 enzymes related to triterpene and polysaccharide biosynthesis were found to be malonylated, indicating an indispensable role of lysine malonylation in bioactive compound biosynthesis in S. sanghuang. Conclusions These findings suggest that malonylation is associated with many metabolic pathways, particularly the metabolism of the bioactive compounds triterpene and polysaccharide. This paper represents the first comprehensive survey of malonylation in S. sanghuang and provides important data for further study on the physiological function of lysine malonylation in S. sanghuang and other medicinal mushrooms.

Overexpression, point mutations or translocations of protein lysine methyltransferase NSD2 was occurred in many types of cancer cells. Therefore, it was recognized as onco-protein and considered as a promising anticancer drug target. NSD2 consists of a SET catalytic domain and two PWWP domains binding to methylated histone proteins. Here, we reported our efforts to develop a series of NSD2 PWWP1 inhibitors, and further structure-based optimization resulted a potent inhibitor 38, which has the high selectivity towards NSD2 PWWP1 domain. The detailed biological evaluation revealed that compound 38 can bind to NSD2-PWWP1 and then affect the expression of genes regulated by NSD2. We believe that the current discovery will provide a useful chemical probe to the future research in understanding the specific regulation mode of NSD2 by PWWP1 recognition.

Herein α-bromoacrylic acids have been employed as C1 insertion units to achieve the palladium-catalyzed [4 + 1] annulation of 2-iodobiphenyls, which provides an efficient platform for the construction of diverse dibenzofulvenes. This protocol enables the formation of double C(aryl)-C(vinyl) bonds via a C(vinyl)-Br bond cleavage and decarboxylation. It is particularly noteworthy that the method features a broad substrate scope, and various interesting frameworks, such as bridged ring, fused (hetero)aromatic ring, and divinylbenzene, can be successfully incorporated into the products.

A new palladium-catalyzed domino alkyne insertion/C–H activation/decarboxylation sequence has been developed, which provides an efficient approach for synthesizing a variety of functionalized phenanthrenes in moderate to good yields. The method shows broad substrate scope and good functional group tolerance by employing readily available materials, including aryl iodides, internal alkynes, and o-bromobenzoic acids, as three-component coupling partners.

A novel palladium-catalyzed cascade cyclization of alkene-tethered aryl halides with o-bromobenzoic acids is described, which provides an efficient avenue for building various fused hexacyclic scaf...

Air pollution containing particulate matter (PM) less than 2.5 μm (PM2.5) plays an essential role in regulating hepatic disease. However, its molecular mechanism is not yet clear, lacking effective therapeutic strategies. In this study, we attempted to investigate the effects and mechanisms of PM2.5 exposure on hepatic injury by the in vitro and in vivo experiments. At first, we found that PM2.5 incubation led to a significant reduction of nuclear factor erythroid-derived 2-related factor 2 (Nrf2), along with markedly reduced expression of different anti-oxidants. Notably, suppressor of IKKε (SIKE), known as a negative regulator of the interferon pathway, was decreased in PM2.5-incubated cells, accompanied with increased activation of TANK-binding kinase 1 (TBK1) and nuclear factor-κB (NF-κB). The in vitro studies showed that Nrf2 positively regulated SIKE expression under the conditions with or without PM2.5. After PM2.5 treatment, Nrf2 knockdown further accelerated SIEK decrease and TBK1/NF-κB activation, and opposite results were observed in cells with Nrf2 over-expression. Subsequently, the gene loss- and gain-function analysis demonstrated that SIKE deficiency further aggravated inflammation and TBK1/NF-κB activation caused by PM2.5, which could be abrogated by SIKE over-expression. Importantly, SIKE-alleviated inflammation was mainly dependent on TBK1 activation. The in vivo studies confirmed that SIKE- and Nrf2-knockout mice showed significantly accelerated hepatic injury after long-term PM2.5 exposure through reducing inflammatory response and oxidative stress. Juglanin (Jug), mainly isolated from Polygonum aviculare, exhibits anti-inflammatory and anti-oxidant effects. We found that Jug could increase Nrf2 activation, and then up-regulated SIKE in cells and liver tissues, mitigating PM2.5-induced liver injury. Together, all these data demonstrated that Nrf2 might positively meditate SIKE to inhibit inflammatory and oxidative damage, ameliorating PM2.5-induced liver injury. Jug could be considered as an effective therapeutic strategy against this disease by improving Nrf2/SIKE signaling pathway., Graphical abstract Image 1, Highlights • PM2.5 incubation inhibits Nrf2 and SIKE activation in vitro. • Nrf2 positively regulates SIKE expression in PM2.5-incubated cells. • SIKE-regulated inflammatory response requires TBK1 blockage in PM2.5-treated cells. • Juglanin treatment suppresses inflammation in PM2.5-incubated cells through increasing SIKE expression.

During meiosis, telomeres attach to the nuclear envelope (NE) to promote homologous chromosome moving, pairing, synapsis, and recombination. The telomere-NE attachment is mediated by SUN1, TERB1-TERB2-MAJIN (TTM complex), and TRF1. The interaction of the TTM complex with shelterin is mediated by TERB1 and TRF1, but how SUN1 interacts with the TTM complex is not yet fully understood. In this study, we found that SUN1 not only interacted with TERB1 but also interacted with MAJIN, and the interaction of SUN1 with MAJIN is stronger than TERB1. We also found that SUN1 interacted with SPDYA, an activator of CDK2. The binding sites of MAJIN and SPDYA at SUN1 were mapped, and both MAJIN and SPDYA bound to the N-terminal domain of SUN1 and the two binding sites were close to each other. Furthermore, SPDYA bound to SUN1 via the Ringo domain and recruited CDK2 to SUN1. Then, we found that the interaction of SUN1 with MAJIN was decreased by the CDK2 inhibitors. Taken together, our results provide the possible mechanism of SUN1, MAJIN, and SPDYA-CDK2 in promoting the telomere-NE attachment during meiosis.

Carbon fiber-reinforced polyetheretherketone (CFRPEEK) possesses biomechanical properties such as elastic modulus similar to human bones and is becoming a dominant alternative to replace the traditional metallic implants. The defective osseointegration and bacterial infection risk of CFRPEEK, however, impede its clinical adoption. In the current study, a newly-developed carbon fiber-reinforced polyetheretherketone/nanohydroxyapatite (CFRPEEK/n-HA) ternary biocomposite was functionalized by covalently grafting carboxymethyl chitosan (CMC) followed by the decoration of a bone-forming peptide (BFP) assisted via the polydopamine tag strategy. Antibacterial test with Staphylococcus aureus (S. aureus) indicated that the CMC and peptide-conjugated substrates (pep-CMC-CFRPEEK/n-HA) significantly suppressed bacterial adhesion. In vitro cell attachment/growth, spreading assay, alkaline phosphatase activity, real-time PCR analysis, osteogenesis-related protein expression and calcium mineral deposition all disclosed greatly accelerated adhesion, proliferation and osteo-differentiation of human mesenchymal stem cells (hMSCs) on the pep-CMC-CFRPEEK/n-HA biocomposite due to the additive effect of the CMC polysaccharide and the small osteoinductive peptide. More importantly, in vivo evaluation of the beagle tibia model by means of micro-CT, histological analysis, SEM observation and fluorescent labeling confirmed the remarkably boosted bioactivity and osteointegration. The CFRPEEK/n-HA ternary composite with the dual functions of bacterial adhesion reduction and osteointegration promotion holds great potential as a bioactive implant material in orthopedic/dental applications based on this scheme.

A sensitive resistive-type gas sensor based on porous silicon (PS)/Pd-loaded WO3 nanowires (NWs) was successfully synthesized via facile methods for detection of ammonia at room temperature. PS/WO3 NWs was synthesized by thermal evaporating W powder on the PS substrate, and Pd nanoparticles were decorated on the surface of WO3 NWs by in-situ reduction method. Compared with PS/WO3 NWs and Pd-loaded WO3 NWs, the PS/Pd-loaded WO3 NWs showed an enhanced response to ammonia at a low concentration down to 1 ppm and exhibited good selectivity, short response-recovery time at room temperature. The improved sensing characteristics indicated that the decoration of Pd NPs is effective for enhancing gas sensing performance.

High modulus asphalt mixtures are increasingly being applied owing to their excellent high temperature performance and fatigue resistance. Currently, they are mainly prepared with admixtures. Aiming at problems of complex processes and poor performance-cost ratios of admixture, Ultra-high molecular weight polymer (UHMWP) was selected as basic material, and cross-linked UHMWP was prepared by a crosslinking reaction. The performances of the UHMWP modified asphalt and cross-linked UHMWP modified asphalt were then compared. UHMWP was determined as modifiers. Through dynamic shear rheometer (DSR) and bending beam rheometer (BBR), the influences of UHMWP content on the basic performance and rheological performance of asphalt were investigated, and their microscopic modification mechanisms were revealed by Scanning electron microscopy (SEM) and differential scanning calorimetry (DSC). The change laws of the dynamic modulus of the UHMWP high modulus mixture with temperature and frequency were clarified, and the change characteristics of their dynamic modulus master curves at different temperatures in different frequency ranges were analyzed. Subsequently, the performances of the different mixtures were evaluated. The results indicate that the performances of UHMWP modified asphalt were better than that of cross-linked UHMWP modified asphalt. As the UHMWP content increases, the high temperature performance of asphalt improves significantly. The rut factor of UHMWP-6 is 79.88% higher than that of UHMWP-4 at 70 ℃. On account of performance and cost, the recommended UHMWP content is 6%. The UHMWP is evenly bound by asphalt and has excellent compatibility. The content of UHMWP has a little effect on the phase change of asphalt. UHMWP mixtures have excellent mechanical performance, and their dynamic modulus reaches 21835 MPa at 15 ℃ and 10 Hz. As the temperature rises, the sensitivity of the dynamic modulus to frequency changes increases.

Insulin-dependent patients with diabetes mellitus require multiple daily injections of exogenous insulin to combat hyperglycemia. However, administration of excess insulin can lead to hypoglycemia, a life-threatening condition characterized by abnormally low blood glucose levels (BGLs). To prevent hypoglycemia associated with intensive insulin therapy, a "smart" composite microneedle (cMN) patch is developed, which releases native glucagon at low glucose levels. The cMN patch is composed of a photo-crosslinked methacrylated hyaluronic acid (MeHA) microneedle array with embedded multifunctional microgels. The microgels incorporate zwitterionic moieties that stabilize loaded glucagon and phenylboronic acid moieties that provide glucose-dependent volume change to facilitate glucagon release. Hypoglycemia-triggered release of structurally unchanged glucagon from the cMN patch is demonstrated in vitro and in a rat model of type 1 diabetes (T1D). Transdermal application of the patch prevented insulin-induced hypoglycemia in the diabetic rats. This work is the first demonstration of a glucose-responsive glucagon-delivery MN patch for the prevention of hypoglycemia, which has a tremendous potential to reduce the dangers of intensive insulin therapy and improve the quality of life of patients with diabetes and their caregivers.

The double-layer vanadium dioxide (VO2) thin film patterned by SiO2 spheres has been fabricated to enhance luminous transmittance (Tlum) without severely expense of solar modulation ability (ΔTsol) for the thermochromic smart windows. The first layer of vanadium thin film was deposited on the substrate with self-assembly SiO2 spheres and then the SiO2 spheres was removed by ultrasonic oscillation. The orderly perforated vanadium thin film with regular pores formed. Afterwards, the second layer of vanadium thin film was deposited on the perforated vanadium thin film. The semi-perforated double layer of vanadium thin film formed and was rapid thermal annealed forming the semi-perforated double VO2 thin films. Compared with continuous VO2 thin film(Tlum, 8.8%, ΔTsol, 5.9%), the semi-perforated double VO2 layer possesses orderly-patterned crater, which facilitate Tlum (42.6%) and only slightly attenuate the ΔTsol (5.5%). The phase transition temperatures for continuous VO2 thin film and the optimized semi-perforated VO2 double layer thin film were 58 °C and 52 °C, respectively, far below 68 °C of bulky VO2. This structure should be very meaningful for the real application of VO2-based smart window in the future.

TiO2, B2O3, H3BO3, B4C and carbon black were used as the raw materials to prepare TiB2 powders by carbothermal reduction method. The influence of different content of carbon black (13.6~14.8 wt%) on products was discussed. The effects of different boron sources and holding time (10~50 min) on the microstructure of TiB2 powders were also investigated. X-ray diffraction (XRD) and scanning electron microscope (SEM) were used to study the phase composition and structural evolution of the powder. The final results showed that hexagonal TiB2 crystal grain could be successfully synthesized without impurities when heated at 1700°C for 30 min in Ar atmosphere with the addition of 14.1 wt% carbon black. Submicrometric TiB2 powders range from 0.5 to 1.0 μm could be obtained when B4C was used as the boron source. The increase in holding time contributed to the grain growth and completion of chemical reactions, but could also result in oversintering.

Vanadium dioxide nanorods with monoclinic crystalline symmetry were grown directly on the commercial ceramic substrate through thermal evaporating vanadium pentoxide powder in a tube furnace. The morphology and crystal structure of as-grown products were characterized by field emission scanning electron microscope and X-ray diffraction respectively. The results showed that the morphology of products could be affected by deposition pressure. Moreover, gas-sensing properties of VO2 nanorods sensors were carried out versus different concentration of methane at room temperature. It was found that the sensor based on VO2 nanorods exhibited a good performance to CH4. This was owing to the special nanorods structure of VO2 material, which providing a large specific surface area. VO2 nanorods efficiently enhanced CH4 gas-sensing performance which provides VO2 a promising semiconductor metal oxide material for application in CH4 sensor.

A certain amount of H 3 BO 3 was preheated at 120 °C for 8 h in order to obtain HBO 2 for preparation of TiB 2 powders by carbothermal reduction. The influence of different amounts of HBO 2 ( 44.9–48.4 wt%), calcination temperature (1400–1800 °C) and the variety of boron sources (H 3 BO 3 , HBO 2 and B 2 O 3 ) on the composition and microstructure of the product was investigated. The resultant powders were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Results showed that impurity-free TiB 2 crystalline powders with the grain size of about 10.0 μm could be successfully prepared at 1700 °C for 30 min in Ar atmosphere when the amount of HBO 2 was 46.7 wt%. Compared with control groups, grains of powders revealed better crystallinity and relatively finer particle size.

Submicrometric TiB 2 powders were synthesized by carbothermal reduction process using titanium dioxide, boron carbide and carbon black as the starting materials. The influence of different amount of boron carbide (22.0–26.8 wt%), calcination temperature (1400–1900 °C) and holding time (15–90 min) on the composition and microstructure of the product was investigated. The resultant powders were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). Results showed that hexagonal impurity-free TiB 2 crystalline powders with the grain size below 1.0 μm could be successfully prepared at 1600 °C for 30 min in Ar atmosphere when the amount of boron carbide was 25.3 wt%. The increase in temperature contributed to reaction completion and grain growth, but the abnormal grain growth and oversintering took place above 1800 °C.

A mechanochromic composite comprises an excimer-forming fluorescent dye dispersed in a compatible polymeric host. Upon large deformation of the polymeric structure, a shift of the fluorescence emission from the excimer band to the monomer band is observed, due to reorganization of dye aggregates. Mechanochromic elastomers can be tailored to produce a reversible optical response during cyclic deformation. Here, we study the optomechanical properties of mechanochromic elastomers undergoing large uniaxial and biaxial deformations. Through detailed experiments and constitutive modeling, we relate the optical response of the mechanochromic elastomer to the deformation of the polymer network. We confirm that optical response is largely reversible and is modulated by the initial dye concentration in the polymer. We adapt the classical Arruda–Boyce model to elucidate microstructural modifications of the polymer–dye blend. We propose a constitutive hypothesis for the optical behavior of the material, which relates variations of the emission spectrum to surface stretching. This knowledge can aid in the design of strain and stress sensors for applications in mechanics, biomechanics, and life sciences.

The rates of restenosis after percutaneous transluminal angioplasty are higher in diabetic than nondiabetic patients. Insulin is protective against restenosis, but these effects are diminished in the case of insulin resistance, which develops with high fat diet (HFD). Therefore, it makes sense to use an insulin-sensitizing compound which also has vasculoprotective effects such as resveratrol. Resveratrol is a phenolic compound found in plant tissues such as the skin of grapes, and has been hypothesized to account for the lower rates of cardiovascular disease among countries with high wine consumption. We have shown that resveratrol decreases neointimal formation in both mouse and rat models of arterial injury, and also that these effects are exerted through eNOS (endothelial nitric oxide synthase). We hypothesized that resveratrol acts though Sirt1, a NAD+-dependent deacetylase, to activate eNOS and decrease neointimal formation, but did not see any difference between neointimal growth of control and Sirt1-/- mice given HFD. AMPK (AMP-activated protein kinase) is an energy sensor which also protects against neointimal hyperplasia in the vasculature via directly activating eNOS and inhibiting the migration of vascular smooth muscle cells. Knocking out the α2 subunit of AMPK in particular has been shown to increase neointimal growth in mouse carotid artery in response to injury. We investigated the effect of resveratrol on neointimal growth after femoral arterial injury of wild type and AMPKα2 knock-out mice given HFD. Resveratrol was given at 0.0375% in the diet two days after wire injury. After 28 days, arteries were harvested and histomorphometric analysis was performed on the cross-sections. We found that neointimal growth was significantly higher in AMPKα2 knock-out mice given resveratrol compared to wild type mice given resveratrol (p Disclosure L. Zhou: None. J. Guo: None. H. Zhang: None. S. Heximer: None. A. Giacca: None.

We demonstrated a visible and near-infrared light tunable photonic nanostructure, which is composed of vanadium dioxide (VO2) thin film and silicon dioxide (SiO2) ordered nanosphere arrays. The vanadium films were sputtered on two-dimensional (2D) SiO2 sphere arrays. VO2 thin films were prepared by rapid thermal annealing (RTA) method with different oxygen flow rates. The close-packed VO2 shell formed a continuous surface, the composition of VO2 films in the structure changed when the oxygen flow rates increased. The 2D VO2/SiO2 composite photonic crystal structure exhibited transmittance trough tunability and near-infrared (NIR) transmittance modulation. When the oxygen flow rate increased from 3 slpm to 4 slpm, the largest transmittance trough can be regulated from 904 to 929 nm at low temperature, the transmittance troughs also appear blue shift when the VO2 phase changes from insulator to metal. The composite nanostructure based on VO2 films showed visible transmittance tunability, which would provide insights into the glass color changing in smart windows.

Ternary nanocomposites based on polyamide-6, maleated butadiene (core) -acrylonitrile-styrene (shell) rubber particles (PB-g-SAM), and modified montmorillonite (organoclay) were prepared by a twin-...

Ebselen a selenoorganic compound showing glutathione peroxidase like activity is an anti-inflammatory and antioxidative agent. Its cytoprotective activity has been investigated in recent years. However, experimental evidence also shows that ebselen causes cell death in several cancer cell types whose mechanism has not yet been elucidated. In this study, we examined the effect of ebselen on multiple myeloma (MM) cell lines in vitro. The results showed that ebselen significantly enhanced the production of reactive oxygen species (ROS) accompanied by cell viability decrease and apoptosis rate increase. Further studies revealed that ebselen can induce Bax redistribution from the cytosol to mitochondria leading to mitochondrial membrane potential ΔΨm changes and cytochrome C release from the mitochondria to cytosol. Furtherly, we found that exogenous addition of N-acetyl cysteine (NAC) completely diminished the cell damage induced by ebselen. This result suggests that relatively high concentration of ebselen can induce MM cells apoptosis in culture by enhancing the production of endogenous ROS and triggering mitochondria mediated apoptotic pathway.

The effect of addition of organoclay and the reactive ABS-g-MA core-shell particles on the mechanical properties and morphology of blends of polyamide (PA6) were reported. The reactive rubber particles with core-shell structure were selected as modifier instead of conventional reactive bulk rubber. The microstructure of the ternary nanocomposites was characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and scanning electron microscopy (SEM). Impact strength and stress–strain behavior of blends were measured as a function of organoclay content and core/shell ratio of ABS-g-MA. The organoclay plates affected the interfacial adhesion between polyamide and the core-shell particles because of a shielding effect of organclay on the interacting of amine end groups of PA6 with the MA groups of ABS-g-MA. The poor dispersion behavior of ternary nanocomposites was observed when the core/shell ratio is 80/20, and with an increase of organoclay content, the core/shell dispersed phase size increased. Blends based on the maleated elastomer with the core/shell ratio 60/40 gave a more beneficial balance of toughness versus stiffness. POLYM. COMPOS., 35:864–871, 2014. © 2013 Society of Plastics Engineers

Reliable life is defined as the average operation time of power equipment in a given reliability, and it is a significant parameter in reliability evaluation. This paper presents a reliable life calculation method for SF 6 circuit breakers. The reliability evaluation model is established based on Fault Tree Analysis (FTA) method. From FTA, all the bottom events which cause top event (failure of the SF 6 circuit breaker) are found. To estimate the reliability by inspection results and test results of the circuit breakers, Health Index (HI) is presented to calculate the failure probability of each bottom event, then the reliability of the top event is obtained. Collecting the failure probability and the age data of different SF 6 circuit breakers with the same type in power system, the data is applied to estimate the reliability function of two parameters Weibull distribution by the least square method. Finally, the reliable life of the SF 6 circuit breaker in a given reliability is estimated after inversion calculation by reliability function. To make further understanding of the method, an application example is presented, and the calculation result shows the effectiveness and accuracy of the model. According to the detailed analysis, the reliable life has more advantage than the physics life to reflect the reliability level of the power equipment.

Pseudomonas fluorescens Pf-5 is a plant commensal bacterium that inhabits the rhizosphere and produces secondary metabolites that suppress soilborne plant pathogens. The complete sequence of the 7.1-Mb Pf-5 genome was determined. We analyzed repeat sequences to identify genomic islands that, together with other approaches, suggested P. fluorescens Pf-5's recent lateral acquisitions include six secondary metabolite gene clusters, seven phage regions and a mobile genomic island. We identified various features that contribute to its commensal lifestyle on plants, including broad catabolic and transport capabilities for utilizing plant-derived compounds, the apparent ability to use a diversity of iron siderophores, detoxification systems to protect from oxidative stress, and the lack of a type III secretion system and toxins found in related pathogens. In addition to six known secondary metabolites produced by P. fluorescens Pf-5, three novel secondary metabolite biosynthesis gene clusters were also identified that may contribute to the biocontrol properties of P. fluorescens Pf-5. Supplementary information The online version of this article (doi:10.1038/nbt1110) contains supplementary material, which is available to authorized users.

In this study, an ordered SiO2 nanosphere array coated with vanadium dioxide (VO2) has been fabricated to enhance transmittance with the potential application as an energy-efficient coating in the field of smart windows. SiO2 arrays were formed using the methods of self-assembly, and VO2 thin films were prepared by rapid thermal annealing (RTA) of sputtered vanadium films. VO2@SiO2 arrays were characterized by scanning electron microscopy, X-ray diffraction, a four-point probe, and UV-vis-NIR spectrophotometry. Compared with the planar films, the films deposited on 300 nm diameter SiO2 nanospheres can offer approximately 18% enhancement of luminous transmission (Tlum) because the diameter is smaller than the given wavelength and the protuberance of the surface array behaves as a gradation of refractive index producing antireflection. The solar regulation efficiency was not much deteriorated.

The glucose oxidase (GOD) gene from Penicillium notatum was expressed in Pichia pastoris. The 1,815 bp gene, god-w, encodes 604 amino acids. Recombinant GOD-w had optimal activity at 35-40°C and pH 6.2 and was stable, from pH 3 to 7 maintaining75% maximum activity after incubation at 50°C for 1 h. GOD-w worked as well as commercial GODs to improve bread making. To achieve high-level expression of recombinant GOD in P. pastoris, 272 nucleotides involving 228 residues were mutated, consistent with the codon bias of P. pastoris. The optimized recombinant GOD-m yielded 615 U ml(-1) (2.5 g protein l(-1)) in a 3 l fermentor--410% higher than GOD-w (148 U ml(-1)), and thus is a low-cost alternative for the bread baking industry.

The multi-alkali photocathode is manufactured on glass surface. The cleanliness of glass surface affects greatly the sensitivity of photocathode. The experience proved that the glow discharge process of glass surface could improve the photocathode sensitivity, but superfluous glow discharge process could also increase the carbon-content of the surface, so that bring on the decay of photocathode sensitivity. This article introduces the effect of glow discharge on photocathode sensitivity and its stability.

Chengyuan Qian, Mengxia Li, Jiangdong Sui, Tao Ren, Zheng Li, Liang Zhang, Liwei Zhou, Yi Cheng, Dong WangCancer Center, Daping Hospital and Research Institute of Surgery, Third Military Medical University, Chongqing, People's Republic of ChinaAbstract: The human apurinic/apyrimidinic endonuclease 1/redox enhancing factor-1 (APE1/Ref-1), an essential multifunctional protein involved in the repair of oxidative deoxyribonucleic acid (DNA) damage and transcriptional regulation, is often overexpressed in tumor tissues and cancer cells. Moreover, APE1/Ref-1 (APE1) overexpression has been linked to chemoresistance in human tumors. Thus, inhibiting APE1 function in cancer cells is considered a promising strategy to overcome resistance to therapeutic agents. Gossypol is a Bcl-2 homology 3 (BH3)-mimetic agent and is able to bind to the BH3 domain of B-cell lymphoma 2 (Bcl-2) family members. Other studies demonstrated that Bcl-2 directly interacted with APE1 via its BH domains. Using apurinic/apyrimidinic (AP) endonuclease assays, we found that gossypol inhibits the repair activity of APE1. Electrophoretic mobility shift assays and dual luciferase assays showed that gossypol could also inhibit the redox function of APE1. Using dual polarization interferometry technology, we show that gossypol can directly interact with APE1. Furthermore, addition of gossypol, in conjunction with APE1 overexpression, leads to cancer cell death. The addition of gossypol also enhances the cell killing effect of the laboratory alkylating agent methyl methanesulfonate and the clinical agent cisplatin (DDP). Administration of gossypol significantly inhibited the growth of xenografts. Furthermore, the combined treatment of gossypol and DDP resulted in a statistically higher antitumor activity compared with DDP alone in vivo. In conclusion, we have demonstrated that gossypol effectively inhibits the repair and redox activity of APE1 through a direct interaction.Keywords: cancer, oxidative DNA damage, BH3-mimetic