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The mechanical property changes in three kinds of ternary borosilicate glasses (named NBS glasses) induced by 8.0-MeV Au3+ were studied by nanoindentation measurements. For these borosilicate glasses, the molar ratio R = [Na2O]/[B2O3] is varied (1.34, 0.75, and 0.40 for NBS1, NBS2, and NBS3, respectively), while their molar ratio K = [SiO2]/[B2O3] is fixed at 4.04. The nanoindentation results indicate that both the hardness and reduced Young modulus were decreased after irradiation. No obvious difference in both hardness and modulus variations of these three NBS glasses was observed. Based on the main structures of their pristine samples, the reedmergnerite groups containing Si-O-BIV may be the structural origin of Au-ion-irradiated mechanical property changes in the homogeneous glasses with R > 0.5. However, the modification of the silica network and phase separation may dominate the mechanical property changes for glasses with R ≤ 0.5. The ion- and electron-irradiation-induced mechanical property changes of these NBS glasses were also compared in this study. The extended incubation dose and the slower decreasing rate can be observed in electron-irradiation-induced hardness and modulus variations, which may be caused by the different mechanisms between both irradiation scenarios.

Zirconolite based glass-ceramic has been deemed as a promising waste form for high-level waste (HLW). In this study, the zirconolite (nominally CaZrTi2O7) glass-ceramic based on a SiO2-B2O3-Na2O-CaO-ZrO2-TiO2-Al2O3 system was sought to be synthesized by two-step thermal treatment. The temperature effects such as nucleation temperature and cooling rate were studied. The influence of the Ce-dopant concentration on crystallization behavior was also investigated. For characterization, powder X-ray diffraction (XRD), thermogravimetry-differential scanning calorimeter (TG-DSC) and scanning electron microscopy (SEM) were applied. Our results illustrate that homogeneous zirconolite with the particle size of 1.8 μm can be the target phase when the glass matrix underwent a rapid cooling process and the nucleation temperature was controlled at around 860 °C. Besides, the results also indicate that the distribution of the zirconolite along with its lattice parameters change regularly as the increase of CeO2 concentration. A larger crystal size of zirconolite phase and some trace amounts of precipitated phases are observed when the CeO2 concentration exceed 3 wt%. This work emphasizes the synthesis of zirconolite glass-ceramic in a SiO2-B2O3-Na2O-CaO-ZrO2-TiO2-Al2O3 system, which is expected to provide basic technical data for underground disposal of HLW.

Borosilicate glass with characteristics of high thermal, mechanical and chemical resistance has plenty of applications. As one of the candidates who are possible to vitrify high level radioactive waste, the borosilicate glass has been studied extensively. The borosilicate glass was added with sodium to increase electrical conductivity and decrease viscosity. The tolerance of sodium borosilicate glass on irradiation is important to vitrification. In this work, the sodium borosilicate glass samples were irradiated with different ions. The dependence of hardness and modulus on irradiation dose was studied. A semi-empirical formulation was proposed. Possible reasons for the change of modulus and hardness were discussed.

Borosilicate glass has potential application for vitrification of high-level radioactive waste, which attracts extensive interest in studying its radiation durability. In this study, sodium borosilicate glass samples were irradiated with 4 MeV Kr 17+ ion, 5 MeV Xe 26+ ion and 0.3 MeV P + ion, respectively. The hardness of irradiated borosilicate glass samples was measured with nanoindentation in continuous stiffness mode and quasi continuous stiffness mode, separately. Extrapolation method, mean value method, squared extrapolation method and selected point method are used to obtain hardness of irradiated glass and a comparison among these four methods is conducted. The extrapolation method is suggested to analyze the hardness of ion irradiated glass. With increasing irradiation dose, the values of hardness for samples irradiated with Kr, Xe and P ions dropped and then saturated at 0.02 dpa. Besides, both the maximum variations and decay constants for three kinds of ions with different energies are similar indicates the similarity behind the hardness variation in glasses after irradiation. Furthermore, the hardness variation of low energy P ion irradiated samples whose range is much smaller than those of high energy Kr and Xe ions, has the same trend as that of Kr and Xe ions. It suggested that electronic energy loss did not play a significant role in hardness decrease for irradiation of low energy ions.

Using 5.9 pb−1 of e + e − annihilation data collected at center-of-mass energies from 3.640 to 3.701 GeV with the BESIII detector at the BEPCII Collider, we measure the observed cross sections of e + e − → K S 0 X (where X = anything ). From a fit to these observed cross sections with the sum of continuum and ψ ( 3686 ) and J / ψ Breit-Wigner functions and considering initial state radiation and the BEPCII beam energy spread, we obtain for the first time the product of ψ ( 3686 ) leptonic width and inclusive decay branching fraction Γ ψ ( 3686 ) e e B ( ψ ( 3686 ) → K S 0 X ) = ( 373.8 ± 6.7 ± 20.0 ) eV, and assuming Γ ψ ( 3686 ) e e is ( 2.33 ± 0.04 ) keV from PDG value, we measure B ( ψ ( 3686 ) → K S 0 X ) = ( 16.04 ± 0.29 ± 0.90 ) % , where the first uncertainty is statistical and the second is systematic.

The environmental impact of the Three Gorges Dam has been a subject of vigorous academic, political and social debate since its inception. This includes the key issue of post-dam river channel erosion, which was predicted by the feasibility study to extend to the river mouth. In this paper we examine the geomorphic response of the channel of the middle Yangtze for 660 km downstream of the dam. Using data on channel characteristics, bed material and sediment transport, we show that in the decade following the dam closure, pre-dam seasonal erosion has been replaced by year-round erosion, a pattern most marked at the upstream end of the study area. The sediment carrying capacity of the river channel has been largely reduced below the dam. The locus of bed scour has moved progressively downstream, ceasing as the bed material became too coarse to be transported (e.g. D50: 0.29 mm pre-dam coarsened to 20 mm below the dam by 2008). About 400 km below the dam there is a reduction in channel slope that changes the sediment carrying capacity from 0.25 kg m−3 to only about 0.05 kg m−3, which is insufficient to move bed sediment. The new long-term hydro-morphological equilibrium that will be established in this section of the middle Yangtze will prevent the further incision downstream initiated by the Three Gorges Dam. The results suggest that the full extent of adverse environmental impact predicted by the pre-dam studies will not eventuate.

Graphene is two dimensional materials which is composited by carbon atoms in honeycomb like lattice. Because of its wonderful characteristics, graphene was studied extensively. In this study, the interaction of highly charged ions (HCI) with the graphene was studied via Raman spectroscopy. The difference of Raman spectra of graphene impacted by HCIs with different charge states was presented. The intensity ratio of D peak to G peak varied with the square root of fluence was displayed. A model that was fitted with experimental results was proposed. According to the model, the potential effect that the size of damaged region grew with potential energy of HCI was proposed for the interaction of HCI with graphene.

Borosilicate glass has potential application for vitrification of high-level waste, which attracts extensive interest in studying their radiation durability. The NBS1 and NBS2 glasses were irradiated with 4 MeV Kr ions. The hardness and modulus of irradiated glasses were measured with a MTS G200 Nanoindenter device. With the increase of the irradiation, both the values of hardness and the modulus dropped and then saturated. The trend was consistent with previous studies, but the decay constants for the hardness of NBS1 and NBS2 were less than those in previous studies.

Glass particles with dimensions typically ranging from tens to hundreds of microns are often used in glass corrosion research in order to accelerate testing. Two-dimensional and three-dimensional nanoscale imaging techniques are badly needed to characterize the alteration layers at the surfaces of these corroded glass particles. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) can provide a lateral resolution as low as ∼100 nm, and, compared to other imaging techniques, is sensitive to elements lighter than carbon. In this work, we used ToF-SIMS to characterize the alteration layers of corroded international simple glass (ISG) particles. At most particle surfaces, inhomogeneous or no alteration layers were observed, indicating that the thickness of the alterations layers may be too thin to be observable by ToF-SIMS imaging. Relatively thick (e.g., 1–10 µm) alteration layers were inhomogeneously distributed at a small portion of surfaces. More interestingly, some large-size (tens of microns) glass particles were fully altered. Above observations suggest that weak attachment and the defects on ISG particle surfaces play an important role in ISG glass corrosion.

In Ref. [1] the BESIII collaboration published a cross section measurement of the process e+e−→π+π− in the energy range between 600 and 900 MeV. In this corrigendum, we report a corrected evaluation of the statistical errors in terms of a fully propagated covariance matrix. The correction also yields a reduced statistical uncertainty for the hadronic vacuum polarization contribution to the anomalous magnetic moment of the muon, which now reads as aμππ,LO(600−900MeV)=(368.2±1.5stat±3.3syst)×10−10. The central values of the cross section measurement and of aμππ,LO, as well as the systematic uncertainties remain unchanged.

Borosilicate glass is a candidate material for radiation waste formation and other optical applications in various fields. To understand the radiation effect of borosilicate glass, heavy ion (Ar q + , Kr q + and Xe q + ) irradiations were used to simulate the alpha and recoiled nuclei irradiations in this study. The surface morphology of glass has been compared to ion irradiation doses and ion energies. The surface topography evolution of irradiated samples is characterized by optical microscopy, atomic force microscopy (AFM), transmission electron microscopy (TEM) and secondary ion mass spectrometry (SIMS). Micro-bumps are observed on the sample surface after irradiation with 5 MeV Xe q + over 5 × 10 13 ions·cm − 2 . The size and density of the bumps increases with increasing irradiation dose. At a low dose, bumps are on the nanometer (nm) scale and rather rare. While the dose is higher than 9 × 10 15 ions·cm − 2 , the size of bumps is on the scale of a few microns, and the density is saturated. However, the height of the bumps increases from a few nm to over 150 nm with further irradiation. The distribution of micro-bumps is nearly homogeneous. The bumps are condensed and swell up, and there is no crystallized structure according to the TEM diffraction pattern. Element migration and concentrations are observed with SIMS imaging. The arrayed micro-bumps are a new finding, and they might be used to change the surface properties. Bump formation is caused by phase separation, and volume swelling is induced by ion irradiation.

The modifications of a commercial borosilicate glass induced by Xe ion irradiation have been studied by Raman spectroscopy and ToF-SIMS depth profiling. A decrease in the average Si–O–Si angle, an increase in the population of three-membered rings and an increase of the glass polymerization are evidenced. The molecular oxygen appears in the irradiated glasses after the irradiation fluence reaches approximately 10 15 ions/cm 2 . The O 2 concentration decreases with the depth of irradiated glass at the ion fluence of 2 × 10 16 ions/cm 2 . A sodium depleted layer at the surface and a depleted zone at around the penetration depth of 5 MeV Xe ions are observed. The thickness of the sodium depleted layer increases with the irradiation fluence. Moreover, comparing with previous results after electron and Ar ion irradiation, it can be concluded that the nuclear energy deposition can partially inhibit the formation of molecular oxygen and increase the threshold value of electron energy deposition for the molecular oxygen formation.

Borosilicate glass samples were irradiated by Xe and Kr ions with different fluences. The nanoindentation hardness of samples was measured. For samples irradiated by Xe and Kr ions, the hardness variation dropped with the irradiation dose in displacement per atom. The experimental results are consistent with those of other studies. A rough model was proposed to explain the results of this study and those of others.

Radiation effects on the mechanical properties of sodium aluminoborosilicate glass induced by 4 MeV Kr, 5 MeV Xe ions and 1.2 MeV electrons have been investigated by nano-indentation measurements. Raman and electron paramagnetic resonance (EPR) spectroscopies were used to characterize the microstructure evolution of electron irradiated samples. The nano-indentation results indicated that the mean hardness was reduced by 12.8%, and the mean reduced Young modulus was increased by 3.5% after heavy ion irradiation. Both the hardness and reduced Young modulus variations reached stabilization when the nuclear deposited energy was around 3 x 10(21) keV(nucl)/cm(3). Although decreases of hardness (about 6.6%) and reduced Young modulus (about 3.1%) were also observed when the deposited electronic energy reached approximately 1.5 x 10(22) keV(elec)/cm(3) after electron irradiation, the results still emphasized that the nuclear energy deposition is the major factor for the evolution in the hardness and modulus of the sodium aluminoborosilicate glass under ion irradiation, rather than a synergy process of the electronic and nuclear energy depositions. (C) 2016 Elsevier B.V. All rights reserved.

Epigenetic regulation has a profound influence on stem cell fate during normal development in maintenance of physiologic tissue homeostasis. Here we report diminished ten-eleven translocation (TET) methylcytosine dioxygenase expression and loss of the DNA hydroxymethylation mark 5-hydroxymethylcytosine (5-hmC) in keratinocyte stem cells and transit amplifying cells in human psoriasis and in imiquimod-induced murine psoriasis. Loss of 5-hmC was associated with dysregulated keratinocyte stem cell kinetics, resulting in accumulation of nestin and FABP5-expressing transit amplifying cells to produce classic psoriatic epidermal architecture. Moreover, 5-hmC loss was accompanied by diminished TET1 and TET2 mRNA expression. Genome-wide mapping of epidermal 5-hmC in murine psoriasis revealed loci-specific loss of 5-hmC in genes regulating stem cell homeostasis, including MBD1, RTN1, STRN4, PRKD2, AKT1, and MAPKAP2, as well as those associated with RAR and Wnt/β-catenin signaling pathways. In vitro restoration of TET expression by ascorbic acid was accomplished in cultured human keratinocyte stem cells to show similar Ca++-induced differentiation, resulting in increased 5-hmC levels and reduced nestin expression. To our knowledge, an epigenetic deficiency in psoriasis with relevance to stem cell dysregulation has not been previously reported. This observation raises the possibility that epigenetic modifiers that impact on the TET–5-hmC pathway may be a relevant approach of heretofore unappreciated therapeutic utility.

Li-rich layered oxides are of great importance as cathode materials for advanced lithium ion batteries. In this work, Li-rich layered Li(Li 0.17 Ni 0.2 Co 0.05 Mn 0.58 )O 2 oxide is synthesized by a spray-drying method, and modified subsequently with CeO 2 nanoparticles. It is demonstrated that the surface of the Li(Li 0.17 Ni 0.2 Co 0.05 Mn 0.58 )O 2 oxide is modified with CeO 2 nanocrystallites, which exist as isolated nano-particles or a thick CeO 2 layer with increasing CeO 2 content. After the surface modification with CeO 2 nanoparticles, Li(Li 0.17 Ni 0.2 Co 0.05 Mn 0.58 )O 2 oxide presents lower surface charge transfer resistance, larger discharge capacity and higher initial coulombic efficiency. In particular, the modified sample with 1 wt % CeO 2 shows the optimized cycle stability and high-rate discharge capability. In addition, the thermal stability of the cathode at delithiated state is improved to a certain extent by the surface modification with CeO 2 nanoparticles, which is attributed to that the oxygen generated from the initial charge can be absorbed and stored in CeO 2 nanoparticles on the surface of Li(Li 0.17 Ni 0.2 Co 0.05 Mn 0.58 )O 2 .

The structural evolutions of a commercial borosilicate glass induced by 2 MeV Ar irradiation have been studied by Raman spectroscopy, and the modification of the mechanical properties has been investigated with nano-indentation tests. The main peaks at approximately 480 cm−1 in the Raman spectra were found to be shifted toward higher wave numbers after irradiation, which means a decrease of the Si–O–Si bond angle. A weak band, which is called a D2 “defect” peak, appears in the Raman spectra of irradiated glasses. A higher concentration of O2 molecules is found in the irradiated glasses; however, the polymerization of the irradiated glass network has not been changed compared with the pristine glass. The mean hardness of the glasses is decreased up to 17% after irradiation, and the variation of the hardness saturates after the deposited nuclear energy reaches approximately 5.5 × 1020 keVnucl cm−3.

Radiation effects on borosilicate glass induced by 0.5 MeV He ions and 1.2 MeV electrons have been investigated by nano-indentation and Raman measurements. The nano-indentation results indicated that the average hardness of the He-irradiated glasses were reduced by 14% with the nuclear energy deposition, and kept constant after the nuclear energy deposition exceeding 5 × 1020 keV/cm3. By the Raman measurements, the polymerization of the silicate network was found to be enhanced by the electronic energy deposition in the electron-irradiated glasses. It is concluded that the nuclear energy deposition is the major factor for the evolution in the plastic response of the borosilicate glass, while the electronic energy deposition influences the change of silicate network and migration of alkaline, which causes sight change of the mechanical properties.

Highly charged Xe q + ( q = 5, 21, 26) ions with kinetic energy of 450 keV were extracted from electron cyclotron resonance ion source. Highly oriented pyrolytic graphite (HOPG) basal surfaces were impacted by the Xe q + ions. The samples were analyzed with Raman spectroscopy. There appeared a tiny peak in Raman spectrum at position of 2643 cm −1 for the impact of Xe 5+ ion, which suggested the monolayer graphene was formed on the HOPG surface. The intensity of the peak depended on the charge state of incident ions.

Experimental observations of self-sustained pitch oscillations of a NACA 0012 airfoil at transitional Reynolds numbers were recently reported. The aeroelastic limit cycle oscillations, herein labelled as laminar separation flutter, occur in the range 5.0×104≤Rec≤1.3×105. They are well behaved, have a small amplitude and oscillate about θ=0°. It has been speculated that laminar separation leading to the formation of a laminar separation bubble, occurring at these Reynolds numbers, plays an essential role in these oscillations. This paper focuses on the Rec=7.7×104 case, with the elastic axis located at 18.6% chord. Considering that the experimental rig acts as a dynamic balance, the aerodynamic moment is derived and is empirically modelled as a generalized Duffing–van-der-Pol nonlinearity. As expected, it behaves nonlinearly with pitch displacement and rate. It also indicates a dynamically unstable equilibrium point, i.e. negative aerodynamic damping. In addition, large eddy simulations of the flow around the airfoil undergoing prescribed simple harmonic motion, using the same amplitude and frequency as the aeroelastic oscillations, are performed. The comparison between the experiment and simulations is conclusive. Both approaches show that the work done by the airflow on the airfoil is positive and both have the same magnitude. The large eddy simulation (LES) computations indicate that at θ=0°, the pitching motion induces a lag in the separation point on both surfaces of the airfoil resulting in negative pitching moment when pitching down, and positive moment when pitching up, thus feeding the LCO.

The tips of cotyledon-stage seedlings of three crape myrtle cultivars (“Zi Wei”, “Hong Wei” and “Yin Wei”) were treated with colchicine. Various concentrations of colchicine and different treatment durations were tested. Seedlings of “Zi Wei” treated with 0.5% colchicine for 72 h and seedlings of “Yin Wei” treated with colchicine (0.2% for 96 h, 0.5% for 48 h and 0.8% for 72 h) demonstrated high rates of mutation; “Hong Wei” showed a slightly lower rate. The highest rate of morphological variation was 54.17% and this was achieved when tips were treated with 0.5% colchicine for 72 h. Putative tetraploid plants were identified with morphological and cytological variations, such as larger and thicker leaves, darker green coloration, larger stomata, lower density of stomata across the lower leaf epidermis and increased numbers of chloroplasts per stomata guard cell. Flow cytometric analysis demonstrated that the nuclear DNA content of 15 of these putative tetraploids (of which 7 were “Zi Wei”, 5 were “Yin Wei”, and 3 were “Hong Wei”) was indeed doubled relative to that of control diploid plants. The chromosome number of the tetraploid plants was 2 n = 4 x = 96, while that of the control diploid plants was 2 n = 2 x = 48. Ornamental characteristics were also enhanced in the tetraploid plants, with increased diameter of the individual flowers and greater basal length of the petals and claws. Pollen diameter and the size of capsules and seeds were also significantly greater than those of diploid plants.

The platelet alpha2beta1 integrin functions as both an adhesion and signaling receptor upon exposure to collagen. Recent studies have indicated that alpha2beta1 function can be activated via inside-out signaling, similar to the prototypical platelet integrin alphaIIbbeta3. However, signaling molecules that regulate alpha2beta1 activation in platelets are not well defined. A strong candidate molecule is the small GTPase Rap1b, the dominant platelet isoform of Rap1, which regulates alphaIIbbeta3 activation.We hypothesized that Rap1b positively regulates alpha2beta1 during agonist-induced platelet activation.To test whether Rap1b activates alpha2beta1 downstream of glycoprotein (GP)VI or other platelet receptors, we stimulated platelets purified from Rap1b-/- or wild-type mice with diverse agonists and measured alpha2beta1 activation using fluorescein isothiocyanate-labeled monomeric collagen. We also examined the role of Rap1b in outside-in signaling pathways by analyzing adhesion and spreading of Rap1b-/- or wild-type platelets on monomeric, immobilized collagen. Finally, we monitored the activation status of related Rap GTPases to detect changes in signaling pathways potentially associated with Rap1b-mediated events.Rap1b-/- platelets displayed comparable ADP-induced or thrombin-induced alpha2beta1 activation as wild-type platelets, but reduced convulxin-dependent alpha2beta1 activation. Rap1b-/- platelets exhibited increased spreading on immobilized collagen but similar adhesion to immobilized collagen compared to wild-type platelets. Rap1b-/- platelets also showed Rap1a and Rap2 activation upon agonist stimulation, possibly revealing functional compensation among Rap family members.Rap1b is required for maximal GPVI-induced but not ADP-induced activation of alpha2beta1 in murine platelets.

Some data in mixed-reactant fuel cells (MRFC) at Newcastle using formic acid, methanol and ethanol are reported. The importance of using a fuel-tolerant selective cathode catalyst has been identified. The influence of fuel and oxidant conditions and feeding patterns has been evaluated. The cell performance using air, oxygen and hydrogen peroxide is reported. The highest peak power density of 16 mW cm −2 was obtained with formic acid. The MRFC gave power densities approximately half those of a conventional, un-mixed-reactant fuel cell.

Samples of microbiotic crusts were collected along the northern part of the Zhongwei–Gantang section of the Baotou-Lanzhou railway, which lies at the southeastern fringe of China's Tengger Desert. We collected intact crust samples, let them recover for 1 year, then created five levels of disturbance: no disturbance (intact crusts), light disturbance (disturbance of 10% and 20% of the total area), moderate disturbance (40% disturbance), and severe disturbance (80% disturbance). We used these samples to simulate the effect of microbiotic crusts on wind erosion. Wind tunnel experiments let us determine the wind velocity required for the initiation of saltation, the threshold velocity (u*), the aerodynamic roughness length (z0), and the wind profile above sand surfaces covered by microbiotic crusts. The wind velocity for the initiation of saltation with an intact microbiotic crust was about 19 m s−1, which is greater than the value of 13.08 m s−1 for shifting sands. z0 was between 0.03 and 0.13 cm, which was larger than the value of 0.0288 for shifting sands, and reached its maximum (0.13 cm) at the 40% disturbance level, and u* was between 0.15 and 1.21 m s−1. The relationships between u*, free-stream wind velocity (u), and z0 followed the equations u*=a+bu and z0=0.01563(1+u*)3.49341. The wind profile above the surface was divided into three sections, with the greatest changes in wind speed occurring below a height of 0.1 m.

Fatigue behaviors of a Ni-based C-2000 superalloy subjected to the surface nanocrystallization and hardening (SNH) process were investigated. The influence of the SNH processing condition on the fatigue properties of the material was analyzed. The near-surface structures of the SNH-treated specimens were characterized by means of the scanning-electron microscopy, X-ray diffraction, and transmission-electron microscopy. It is shown that the SNH is an effective method to render the material with the features, such as a nanostructured and work-hardened surface layer as well as compressive residual stresses, which can pronouncedly improve the fatigue strength of the material. However, excessive treatments deteriorate the fatigue properties, and the surface contaminations are considered to be the main reason.

The use of ruthenium-selenium-tungsten catalysts as methanol tolerant cathodes for direct methanol fuel cells is reported. The novel catalysts were produced by decarbonylation of ruthenium and tungsten carbonyls in the presence of selenium and carbon powders. The produced materials were characterised in both half cells and fuel cells. The addition of tungsten led to better oxygen reduction performance, giving current densities up to 30% greater and cell power densities up to 25% greater than those obtained with ruthenium-selenium alone. There is only a minor loss in methanol tolerance in the presence of tungsten. The improvement in performance is a consequence of the beneficial influence of tungsten on the structure and properties of catalysts. The effects of fuel cell operating conditions are also reported. The new catalysts were compared to Pt.

The activity of ruthenium-based catalysts towards oxygen reduction was enhanced by addition of tungsten, molybdenum and rhodium. The catalysts were produced by decarbonylation of the ruthenium and transition metal carbonyls in the presence of selenium (sulphur) and carbon powders. The produced materials were characterised by scanning electron microscopy and energy dispersive spectroscopy as well as by electrochemical evaluations in both half cells and direct methanol fuel cells. All transition metal-modified catalysts exhibited better performance than those of ruthenium–selenium (sulphur) alone, but the tungsten modification seemed the best approach. The RuSe0.20W0.29 catalyst delivered the maximum power density of up to 40 mW cm−2. The improvement is a consequence of the enhanced activity towards oxygen reduction with a minor loss in methanol tolerance as well as a stabilising effect of tungsten on catalysts. The new catalysts were compared to Pt and to sulphur-containing catalysts.

Carbon-supported platinum–iron catalysts were prepared and characterised by means of scanning electron microscopy, energy-dispersive X-ray and X-ray diffraction techniques. The catalysts were tested for oxygen reduction in half-cells and in direct methanol fuel cells using voltammetric and steady-state polarisation measurements. Methanol oxidation was partially suppressed and higher net oxygen reduction currents were achieved at the PtFe/C cathodes, compared to the Pt alone. An increase in power density of up to 20–30% was achieved by using the PtFe/C rather than the Pt/C cathodes.

Exposure to arsenic through domestic burning arsenic-containing coal causes various tumors in a population of Guizhou, China. The glycophorin A (GPA) assay is a human mutation assay detecting somatic variation in erythrocytes expressing the MN blood type, and was used to assess genotoxicity of arsenic-exposed patients. Peripheral blood was collected from 18 adult healthy subjects and 40 arsenic-exposed patients in heparin-treated tubes. Erythrocytes were isolated, fixed in formalin and immuno-labeled with fluorescent antibodies against GPA, followed by flow cytometry analysis. Arsenic exposure increased the variant frequency (expressed as the number of variant red cells per 10(6) erythrocytes): NN, 3.7 in healthy subjects versus 21.2 in arsenic-exposed patients; N phi, 12.6 versus 33.1; MM, 13.1 versus 110; and M phi, 5.2 versus 20.3. The total GPA variant frequency was increased about five-fold (34.7 in healthy subjects versus 185 in arsenosis patients). Furthermore, the variant frequency was significantly higher in skin tumor-bearing patients: NN, 19.4 in arsenic-exposed non-tumor patients versus 31.5 in tumor-bearing patients; N phi, 29.5 versus 54.5; MM, 102 versus 159; M phi, 15.9 versus 45.1. Total GPA variant frequency in arsenic-exposed patients bearing skin tumors was significantly increased compared to patients without skin tumors (167 versus 290). The relationship between arsenic exposure history and GPA variant frequency was less evident. These data demonstrate that arsenic exposure is associated with mutations at the GPA locus, an effect exaggerated in patients bearing arsenic-induced skin tumors. The variant frequency of GPA could be a useful biomarker for arsenic exposure and arsenic carcinogenesis.

A new procedure has been introduced to enhance catalytic activity of ruthenium–selenium electro-catalysts for oxygen reduction, in which materials are treated under hydrogen atmosphere at elevated temperatures. The characterisation using scanning electron microscopy, energy dispersive spectroscopy or energy dispersive X-ray spectroscopy exhibited that the treatment at 400 °C made catalysts denser while their porous nature remained, led to a good degree of crystallinity and an optimum Se:Ru ratio. The half cell test confirms feasibility of the new procedure; the catalyst treated at 400 °C gave the highest reduction current (55.9 mA cm −2 at −0.4 V) and a low methanol oxidation effect coefficient (3.8%). The direct methanol fuel cell with the RuSe 400 °C cathode catalyst (2 mg RuSe cm −2 ) generated a power density of 33.8 mW cm −2 using 2 M methanol and 2 bar oxygen at 90 °C. The new procedure produced the catalysts with low decay rates. The best sample was compared to the Pt and to the reported ruthenium–selenium catalyst. Possible reasons for the observations are discussed.

We describe an ongoing programme to search for X-ray sources with long-term, large amplitude X-ray variability. The method is to compare the X-ray sources from the XMM-Newton Serendipitous Survey with those from the previous ROSAT pointed observations and the ROSAT All-sky Survey. The work is largely motivated by the recent discovery of a new type of X-ray flares characterised by enormous amplitude flux variability and associated with normal galaxies [Komossa, S., Ludwig Biermann Award lecture: X-ray evidence for supermassive black holes at the centers of nearby, non-active galaxies. Rev. Mod. Astron. 15, 27, 2002]. Other objects of interest are black hole accretion systems, such as X-ray binaries and AGN, GRB afterglows, extremes of stellar flares, and other objects undergoing extremely violent physical processes. In this paper, we describe the programme and present some preliminary results. (c) 2005 COSPAR. Published by Elsevier Ltd. All rights reserved.

The thermomechanical postbuckling behaviour of composite laminated plates is studied with the aid of the B-spline finite strip method under the combination of temperature load and applied uniaxial mechanical stress. To account for through-thickness shear deformation effects, the thermal-elastic, first-order shear deformation (Reissner–Mindlin) plate theory is used in this paper. General boundary conditions and laminate lay-ups can be accommodated in the newly developed finite strip approach. A range of applications is described and the results generated by the finite strip procedure are compared with the results of previous studies. The spline finite strip method is shown to be versatile and accurate with good convergence qualities.

The high-cycle fatigue (HCF) behavior of the Zr 41.2 Ti 13.8 Cu 12.5 Ni 10 Be 22.5 (in at.%) bulk-metallic glass (BMG) was studied. Two batches of samples that are from different lots (Batches 59 and 94) are employed in present experiments. The HCF experiments were conducted, using an electrohydraulic machine at a frequency of 10 Hz with a R ratio of 0.1 in air at room temperature and under tension-tension loading, where R = σ min. / σ max. . ( σ min. and σ max. are the applied minimum and maximum stresses, respectively). A high-speed and high-sensitivity thermographic-infrared (IR) imaging system was employed for the nondestructive evaluation of temperature evolutions during fatigue testing. No distinct sparking phenomenon was observed at the final fracture moment for this alloy. The fatigue lifetime of Batch 59 is longer than that of Batch 94 at high stress levels (maximum stresses >864 MPa). Moreover, the fatigue-endurance limit of Batch 59 (703 MPa) is somewhat greater than that of Batch 94 (615 MPa). The vein pattern and liquid droplets were observed in the apparent-melting region along the edge of the fractured surfaces. The fracture morphology suggests that fatigue cracks initiated from casting defects, such as porosities and inclusions, which have an important effect on the fatigue behavior of BMGs.

We outline the motivation and conceptual design for a new experiment aimed at a 10-fold improvement in the accuracy of the parity-violating asymmetry A_gamma in the angular distribution of 2.2 MeV gamma rays from the n+p-->d+gamma reaction. This observable is primarily sensitive to the weak pion-nucleon coupling H_pi^1. A proof-of-principle experiment using unpolarized low-energy neutron capture on polyethylene and an array of 12 CsI detectors operated in current mode has been performed. Results of this test experiment including the current mode signal, electronic noise and detector sensitivity to magnetic fields are reported., Comment: 19 pages, 9 eps figures, uses RevTeX and epsfig, submitted to NIM

Public participation as a means of identifying sustainability indicators for Chongming County, Shanghai, China was evaluated by an international group drawing on established best practice. An initial 'long list' of 86 sustainability indicators, based on previous indicator systems developed in China, was identified. This 'long list' was reduced via consultations with local academics and local-government officers from Shanghai City and Chongming County to a 'short list' of 17 indicators. This short-list was subjected to further community consultation involving 159 local-government officers, teachers, students (aged 12-14 years), farmers and workers. Data from the consultations indicated differences in the understanding of sustainable development among the different sectors. By combining the data from the different sectors it was possible to identify a consensus around 4 core and 7 additional indicators. These are proposed as indicators which could be used to steer local activities directed towards sustainable development. The list of indicators produced by the people of Chongming Island was compared to local indicator systems in Europe. In comparison with European lists the Chongming list was found to have a greater emphasis on economic development but a similar level of concern for environmental matters. This study has special significance as it reports on the implementation of a process involving local resident participation in the process of sustainable development in China.

An experiment to measure γ-ray asymmetry A γ with a high precision in neutron-proton radiative capture is under construction at LANSCE. The experiment will determine the weak pion-nucleon coupling constant H π 1 ,, 30% of its predicted value.

Proteolytic fragments generated by ADAMTS ( a d isintegrin a nd m etalloprotease with t hrombo s pondin motifs)-mediated cleavage of the aggregating chondroitin sulfate proteoglycan, brevican, have been identified, but not localized in the CNS. The purpose of this study, using kainate-induced CNS lesion, was to examine the spatial and quantitative relationship between ADAMTS1 and 4 mRNA expression and ADAMTS-mediated cleavage of brevican (as determined by the abundance of the neo-epitope QEAVESE at the C-terminal of the cleaved brevican G1 domain). In untreated rats, in situ hybridization and reverse transcriptase polymerase chain reaction indicated that ADAMTS4 expression was higher than ADAMTS1 and was localized to hippocampus, temporal lobe and other areas of cortex, striatum and hypothalamus. ADAMTS4 mRNA expression in these regions correlated with the presence of the QEAVESE neo-epitope, which was concentrated in perineuronal nets and in neuropil. In rats that seized after kainate, there was a dramatic elevation in ADAMTS1 and ADAMTS4 transcript that correlated and co-localized with a robust elevation in an extractable, 55-kDa fragment of brevican in temporal lobe and hippocampus. This fragment consisted, at least in part, of the ADAMTS-cleaved epitope G1-QEAVESE. The kainate-induced elevation in this ADAMTS-cleaved fragment was localized to amygdaloid and thalamic nuclei, hippocampus, caudate–putamen, cingulate cortex, and the outer molecular layer of the dentate gyrus where it was accompanied by a robust elevation in ADAMTS1 and 4 mRNA and a 28% decline in synaptic density 5 days after kainate. Thus, complexes of extracellular matrix proteins that exist in perineuronal nets and in the neuropil are cleaved by specific matrix-degrading proteases at early time points during excitotoxic neurodegeneration. The observed ADAMTS-induced cleavage of brevican in the dentate outer molecular layer is closely associated with diminished synaptic density, and may, therefore, contribute to synaptic loss and/or reorganization in this region.