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During the Ordovician, huge biological revolutions and environmental changes happened in Earth’s history, including the Great Ordovician Biodiversification Event, global cooling and so on, but the cause of these events remains controversial. Herein, we conducted a paired carbon isotopic analysis of carbonate (δ13Ccarb) and organic matter (δ13Corg) through the Ordovician in the Qiliao section on the Yangtze platform of South China. Our results showed that the δ13Ccarb trend of the Qiliao section can be correlated with local and global curves. The δ13Corg trend seems is less clear than the δ13Ccarb trend for stratigraphic correlations, but some δ13Corg positive excursions in the Middle and Upper Ordovician may be used for correlation studies. These carbon isotopic records may have global significance rather than local significance, revealing several fluctuations to the global carbon cycle during the Ordovician. Several known δ13Ccarb and δ13Corg negative and positive excursions have been recognised in this study, including the early Floian Negative Inorganic Carbon (δ13Ccarb) Excursion (EFNICE), as well as the early Floian Positive Organic Carbon (δ13Ccarb) Excursion, the mid-Darriwilian Inorganic Carbon (δ13Ccarb and δ13Corg) Excursion (MDICE), and the early Katian Guttenberg Inorganic Carbon (δ13Ccarb and δ13Corg) Excursion (GICE). These positive excursions and a smooth decline trend of δ13Corg values during the early to mid-Floian may imply multiple episodes of enhanced organic carbon burial that began at the early Floian stage, probably resulting in further decline in atmospheric pCO2 and then global cooling. [ABSTRACT FROM AUTHOR]

H-related defects have been investigated in Ga-doped ZnO thin films deposited by RF magnetron sputtering at room temperature in Ar+H2ambient. When the flow ratio of H2/(Ar+H2) increases from 0 to 4%, the resistivity significantly decreases from 1·94 × 10−2to 5·69 × 10−4 Ω cm. X-ray diffraction and X-ray photoelectron spectroscopy results show that it should not be ascribed to the films’ crystalline quality, the chemical states and substitutional situation of Ga and Zn. It is suggested that there are a large number of acceptors in the films, the major role of H is to passivate the acceptors but H-donors themselves do not play a significant role. These acceptor-like defects are located at grain boundaries (dangling bonds) and in bulk (VZnand/or GaZn–VZn). Post-growth annealing experiment and optical transmittance results exhibit that the passivated acceptors are mainly at grain boundaries rather than in bulk. [ABSTRACT FROM PUBLISHER]

Transforming growth factor-β1 (TGF-β1) induces expression of the proinflammatory and profibrotic cytokine monocyte chemoattractant protein-1 (MCP-1) in tubular epithelial cells (TECs) and thereby contributes to the tubular epithelial–mesenchymal transition (EMT), which in turn leads to the progression of tubulointerstitial inflammation into tubulointerstitial fibrosis. Exactly how TGF-β1 causes MCP-1 overexpression and subsequent EMT is not well understood. Using human tubular epithelial cultures, we found that TGF-β1 upregulated the expression of reduced nicotinamide adenine dinucleotide phosphate oxidases 2 and 4 and their regulatory subunits, inducing the production of reactive oxygen species. These reactive species activated a signaling pathway mediated by extracellular signal-regulated kinase (ERK1/2) and nuclear factor-κB (NF-κB), which upregulated expression of MCP-1. Incubating cultures with TGF-β1 was sufficient to induce hallmarks of EMT, such as downregulation of epithelial marker proteins (E-cadherin and zonula occludens-1), induction of mesenchymal marker proteins (α-smooth muscle actin, fibronectin, and vimentin), and elevated cell migration and invasion in an EMT-like manner. Overexpressing MCP-1 in cells exposed to TGF-β1 exacerbated these EMT-like changes. Pretreating cells with the antioxidant and anti-inflammatory compound arctigenin (ATG) protected them against these TGF-β1-induced EMT-like changes; the compound worked by inhibiting the ROS/ERK1/2/NF-κB pathway to decrease MCP-1 upregulation. These findings suggest ATG as a new therapeutic candidate to inhibit or even reverse tubular EMT-like changes during progression to tubulointerstitial fibrosis, and they provide the first clues to how ATG may work. [ABSTRACT FROM AUTHOR]

The authors reflect on the science of mild traumatic brain injury. They argue on the limited science in the said brain disorder. The authors suggest the need to establish an inter-institutional neuroimaging consortium to discover clinically relevant diagnostic biomarkers and develop evidence-based interventions to facilitate recovery.

Al doped ZnO (AZO) thin films were synthesised on quartz glass substrates by pulsed laser deposition (PLD) method at different oxygen flowrates. The structure, composition, optical and electrical properties in the films were investigated. The result of surface profiler shows that with the increase in oxygen flowrate from 10 to 70 sccm, the films' thickness increases from 526 to 706 nm. X-ray diffraction results show that the crystalline quality of the films is improved with the increase in oxygen flowrate; energy dispersive spectroscopy results exhibit that the Al content in the films increases from 4·32 to 6·45% with the increase in oxygen flowrate. The former leads to the weakening of grain boundary scattering; consequently, Hall mobility will increase, and the latter results in the increase in carrier concentration. As a result, the electrical resistivity in AZO films decreases from 10·92×10−3 to 2·34×10−3 Ω cm with increasing the oxygen flowrate. Moreover, the increase in carrier concentration induces the slight widening of optical band gap due to the Burstein-Moss effect with the increase in oxygen flowrate. For AZO thin films grown by the PLD method, the control of oxygen flowrate is a simple method to obtain adjustable electrical resistivity, optical band gap and ultraviolet emission. [ABSTRACT FROM AUTHOR]

Al doped ZnO (AZO) thin films were synthesised on single crystal silicon and quartz glass substrates by pulsed laser deposition method at different O2 partial pressure. The structure, composition, optical and electrical properties in AZO thin films were investigated. With the increase in O2 partial pressure, the crystalline quality of AZO thin films becomes poor, and the Al content in the films decreases from 6·3 to 4·3%. The former leads to the enhancement of grain boundary scattering, consequently Hall mobility will decrease. While the latter results in the decrease of carrier concentration. As a result, the electrical resistivity in AZO thin films increases from 2·18×10−4 to 13·40×10−4 Ω cm with increasing the O2 partial pressure. The increase of carrier concentration induces the widening of optical band gap due to the Burstein-Moss effect with the increase of O2 partial pressure. For AZO thin films grown by PLD method, the control of O2 partial pressure is a simple method to adjust the electrical resistivity, optical band gap and UV emission in the films. [ABSTRACT FROM AUTHOR]

Progressive-pressure electrolyte flow is employed to improve efficiency and accuracy of radial electrochemical machining of blisk channels. Flow field simulation indicates that the use of progressive-pressure flow gives a high electrolyte flow rate in the inter-electrode gap, allowing a high cathode feed rate without shortcut. Experiments show that the high feed rate leads to high machining efficiency. Under the progressive-pressure flow, the surface roughnesses of the convex part, concave part, and hub of channels are reduced and the machining accuracy of the hub is enhanced. Furthermore, the allowances of the hub can be reduced by using progressive-pressure electrolyte flow. [ABSTRACT FROM PUBLISHER]

Al doped ZnO (AZO) thin films are of significant interest for flat panel displays, solar cells, etc. In this regard, AZO films were prepared in Ar atmosphere by radio frequency magnetron sputtering with an AZO (2 wt-%Al2O3) ceramic target at room temperature. To investigate the influence of hydrogen related defects on the structure and optoelectronic properties in AZO films, the prepared films were annealed in Ar+H2 ambient at different temperatures (100-500°C). The results show that the films' crystallinity becomes better and the resistivity decreases with the increase in annealing temperature. The lowest resistivity of 2·79×10−3 Ω cm is obtained after 500°C hydrogen annealing, which decreases by about four orders of magnitude compared to the resistivity of as deposited film. The improvement of electrical properties is attributed to the formation of H related defects and desorption of weakly bonded oxygen species near grain boundaries in AZO films after H2 annealing treatment, and the corresponding physical mechanism was discussed. It is proved that hydrogen annealing is an effective method for the improvement of electrical properties in AZO thin films. The optical bandgap energy of the films obviously increases with the increase in annealing temperature due to Burstein-Moss effect. [ABSTRACT FROM AUTHOR]

This paper describes the development of screen printed vibration energy harvesters developed at the University of Southampton. The mark 1 harvester developed very low levels of power (2 μW) due to the poor piezoelectric properties of the printed film. Properties were improved by blending particle sizes and optimising firing and poling conditions. The new piezoelectric paste was applied to harvesters developed for the EU funded project TRIADE. Power outputs have improved to 240 μW from an excitation vibration of 0·29grms (g=9·8 m s-2) at 67 Hz. Multilayer structures also demonstrate further improvements, and the harvester has been demonstrated powering an autonomous wireless sensor system for condition monitoring. [ABSTRACT FROM AUTHOR]

To obtain an ultra-low sidelobe level of adaptive digital beamforming, a process of design-ing auxiliary beams is introduced into the conventional adaptive sidelobe canceller (ASLC). In contrast to auxiliary elements utilized in ASLC, the steering directions of auxiliary beams are in accordance with jamming locations, and approximately orthogonal to the qui-escent sum beam. Thus, the proposed beamformer can not only suppress the sidelobe level, but also reduce the processor's degrees of freedom, which consequently results in a fast convergence rate and a much lower computational load. [ABSTRACT FROM AUTHOR]

The authors introduce an entirely new Multilayer Transient Testing approach that uses transient temperature data at multiple locations together with a single-point transient pressure measurement. The article presents the complete mathematical model including the forward and inverse models. The forward model couples wellbore and reservoir models for simulating transient temperature and pressure for single-phase flow, and it is used to investigate the possibility of evaluating formation properties from transient temperature and pressure measurements. With the inverse model, permeability, damaged permeability, and damaged radius in multiple layers can be quantified as independent regression parameters. [ABSTRACT FROM PUBLISHER]

Thermal energy storage plays an important role in a wide variety of industrial, commercial, and other applications when there is a serious mismatch between the supply and demand of energy. Latent heat storage with phase change materials is very attractive, because of its high-energy storage density and its isothermal behavior during the phase change process. Here, the heat transfer enhancement in a two-dimensional enclosure containing nanofluids is solved using Fluent 6.2 software. Starting with steady natural convention, the phase change behavior is simulated considering different volume fractions of the SiC-H2O nanofluids. The simulation results show that the freezing rate of nanofluids is enhanced due to the addition of nanoparticles. The higher the volume fraction is, the shorter the total freezing time. Adding 5% SiC nanoparticles into water, the total freezing time can be saved by 17.4%. The computation results show that adding nanoparticles is an efficient way to enhance the heat transfer in a latent heat thermal energy storage system. [ABSTRACT FROM AUTHOR]

This paper discusses an implementation of bistatic polar format algorithm (PFA) using chirp scaling (CS). The new algorithm applies CS in the range direction to realize the range resampling, which involves only complex multiplications and FFTs. The dechirped and the chirped signals are treated separately. The new approach obtains comparable results compared with the original algorithm, however improves the efficiency significantly. Point target simulation validates the new algorithm. [ABSTRACT FROM AUTHOR]

Modified paraffin wax instead of natural bee wax has been used in the modified research of the automobile polish wax formula. The influence of the quality fraction of self-prepared emulsifier and thickener, as well as the emulsified craft conditions such as emulsified temperature, emulsified time, and agitate speed, on the emulsified wax performance were investigated separately. The results indicated that with the paraffin wax and the modified paraffin wax as the raw material, the quality fraction of the compound emulsifier was 2.1 ~ 2.5 wt% and the quality fraction of the thickener was 2.9 ~ 3.4 wt% at the technical condition of the emulsified temperature 85°C, the emulsified time of 40 min, and the agitate speed of 1000 r/min. The emulsified wax product was the translucent and neutral white emulsion with the blue light. The product would still be stable when it is laid aside for more than 60 ds. This emulsified wax was the raw material for automobile polish wax, which contained paraffin wax and the modified paraffin wax at 15 ~ 20 wt%. The emulsified automobile polish wax was prepared by adding some other surface active agents, luminous agent, and other promoters. This product would allow for cleaning, polishing, and waxing at the same time and operate easily with good effects. [ABSTRACT FROM AUTHOR]

The aim of this study was to develop and validate a method of determining the warm and cold edges of the Vegetation Temperature Condition Index (VTCI) drought monitoring approach, and to analyse the time series profiles of the VTCI in croplands under both rainfed and irrigated conditions. The linear correlation coefficients between the VTCI and the cumulative precipitation at one or two periods of 10-day intervals are the highest. There are significant linear correlations between the VTCI and soil moisture at the 0-10-cm layer for each 10-day interval during the winter wheat growing seasons. These results indicate that the VTCI is an effective approach for monitoring drought occurrence after the crops turn green. The time series analysis of the VTCI in the 10-day intervals shows that the VTCI profiles are different for irrigated and rainfed conditions. The time series VTCI values under rainfed conditions have a good response to recent precipitation, while those under irrigated conditions have less agreement with recent precipitation due to irrigation practices. The results show that the VTCI is a better indicator of droughts than indices developed from precipitation data. [ABSTRACT FROM AUTHOR]

Carpesides A (1) and B (2), two new 8-O-4'-neolignan glucosides, and eupatriol 9-O-[beta]-d-apiofuranosyl-(1 --> 6)-[beta]-d-glucopyranoside (3), one new monoterpenoid diglycoside, together with 10 known glycosidic compounds, were isolated from the aerial part of Carpesium cernuum L. The structures of the new glycosides are elucidated by means of chemical methods and spectroscopic studies. [ABSTRACT FROM AUTHOR]

In this paper, a fast identification algorithm for non-linear dynamic stochastic system identification is presented. The algorithm extends the classical orthogonal forward regression (OFR) algorithm so that instead of using the error reduction ratio (ERR) for term selection, a new optimality criterion, Shannon's entropy power reduction ratio (EPRR), is introduced to deal with both Gaussian and non-Gaussian signals. It is shown that the new algorithm is both fast and reliable and examples are provided to illustrate the effectiveness of the new approach. [ABSTRACT FROM AUTHOR]

The refinement of the grain size of electroformed deposits is an important way to improve the properties of the deposits. In the present study, Ni–Mn alloys in which the grain sizes approached ∼100 nm or below were electroformed by using a high frequency pulse power supply. The influence of the average deposition current density and pulse parameters on microhardness and tensile properties of the pulse electroformed Ni–Mn alloys was studied. The results show that the current parameters influence the properties of the alloys by changing their Mn content and grain size. With increase in average current density, microhardness and strength of the alloys increase and the elongation ratio decreases because of the increment of Mn content of the alloys and the decrement of grain size of the alloys. A shorter pulse on time and larger duty cycle contribute to higher microhardness and strength of the alloys. [ABSTRACT FROM AUTHOR]

The conventional cerebellar model articulation controllers (CMAC) learning scheme equally distributes the correcting errors into all addressed hypercubes, regardless of the credibility of those hypercubes. This paper presents the adaptive fault-tolerant control scheme of non-linear systems using a fuzzy credit assignment CMAC neural network online fault learning approach. The credit assignment concept is introduced into fuzzy CMAC weight adjusting to use the learned times of addressed hypercubes as the credibility of CMAC. The correcting errors are proportional to the inversion of learned times of addressed hypercubes. With this fault learning model, the learning speed of fault can be improved. After the unknown fault is estimated, online, by using the fuzzy credit assignment CMAC, the effective control law reconfiguration strategy based on the sliding mode control technique is used to compensate for the effect of the fault. The proposed fault-tolerant controller adjusts its control signal by adding a corrective sliding mode control signal to confine the system performance within a boundary layer. The numerical simulations demonstrate the effectiveness of the proposed CMAC algorithm and fault-tolerant controller. [ABSTRACT FROM AUTHOR]

Two new 18-carbon norditerpenoid alkaloids, sinaconitines A (1) and B (2), together with two known alkaloids, ranaconitine (3) and lappaconitine (4), were isolated from the roots of Aconitum sinomontanum. Their structures were elucidated on the basis of spectral evidences and X-ray crystallographic analysis for 1. Furthermore, the reversed 13C NMR assignments for C-10 and C-13 of 3, 4, puberanine, puberanidine and demethyllappaconitine were revised. Compounds 1–4 were evaluated for cyclooxygenase-2 (COX-2) enzyme inhibitory activity. However, they did not show any inhibition at 10 μM. [ABSTRACT FROM AUTHOR]

Urceolatol ( 1 ), a novel bromobenzaldehyde dimer, together with one known bromophenol, 3-bromo-4,5-dihydroxy-benzaldehyde ( 2 ), were isolated from the red alga Polysiphonia urceolata. The structure and absolute stereochemistry of 1 were elucidated to be (5 R ,10 R )-2,7-dibromo-3,8-dihydroxy-5,10-dimethoxyl-5,10-dihydrochromeno[5,4,3-cde]chromene, on the basis of spectroscopic techniques and X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

Five-coordinate Schiff-base Zn complexes (1,2-cyclohexanediamino-N,N′-bis(salicylidene)) zinc-pyridine 1 and (1,2-cyclohexanediamino-N,N′-bis(3,5-di-tert-butylsalicylidene)) zinc-pyridine 2 were synthesized and the structures of 1 and 2 have been determined by single-crystal X-ray analysis. All Zn atoms are five-coordinate in both structures. Both complexes exhibit interesting structures based on intermolecular π–π stacking and hydrogen bond interactions. Complex 1 has a one-dimensional molecular chain structure via π–π stacking interaction, while complex 2 has an interesting lattice structure (with cavities with dimensions 10.9  ×  6.9  Å) formed through intermolecular π–π stacking and hydrogen bond interactions. 1 and 2 are compared and characterized by MS, elemental analysis, IR, UV-Vis and Photoluminescence (PL). Fluorescence spectra show that the maximal emission wavelength of 1 and 2 are 454  nm, and 480  nm, respectively, upon radiation by UV light. Cyclic voltammetry performed on 1 and 2 indicate a dependence of the cathodic potentials upon conformational and electronic effects. Electronic spectral properties of 1 and 2 were studied by TD-DFT methods. The fluorescent emission of these complexes originates from ligand-centred π–π* transitions. The Zn (II) centres play a key role in enhancing the fluorescent emission of the ligands. [ABSTRACT FROM AUTHOR]

Two new phloroglucinol derivatives, named ebracteolatain A and ebracteolatain B, along with three known phloroglucinol derivatives were isolated from Euphorbia ebracteolata Hayata., and their structures were elucidated as 3,3'-diacetyl-2,4'-dimethoxy-2',4,6,6'-tetrahydroxy-5'-methyl diphenylmethane (1) and 1-[3,5-bis-(3-acetyl-2,6-dihydroxy-4-methoxy-benzyl)-2,4,6-trih ydroxy-phenyl]-ethanone (2) on the basis of spectroscopic techniques and chemical methods. [ABSTRACT FROM AUTHOR]

In this paper, a mathematical program with complementarity constraints (MPCC) is reformulated as a nonsmooth constrained mathematical program via the Fischer–Burmeister function. Smooth penalty functions are used to treat this nonsmooth constrained program. Under linear independence constraint qualification, and upper level strict complementarity condition, together with some other mild conditions, we prove that the limit point of stationary points satisfying second-order necessary conditions of unconstrained penalized problems is a strongly stationary point, hence a B-stationary point of the original MPCC. Furthermore, this limit point also satisfies a second-order necessary condition of the original MPCC. Numerical results are presented to test the performance of this method. [ABSTRACT FROM AUTHOR]

1. The intestinal permeability and hepatic metabolism of the investigational cancer chemoprevention agent 4′-bromoflavone were investigated in vitro using human intestinal Caco-2 cell monolayers, human liver microsomes and human hepatocytes. Liquid chromatography-mass spectrometry and tandem mass spectrometry were used for quantitative analysis in support of the Caco-2 cell studies and for the characterization of metabolites of 4′-bromoflavone. 2. The Caco-2 cell model indicated that 4′-bromoflavone would be absorbed by the intestine at a moderate rate by means of direction-independent, passive diffusion. There was no indication of active transport or efflux. 3. Three monohydroxylated metabolites and one monohydroxylated, hydrated metabolite of 4′-bromoflavone were detected at relatively low levels in the human liver microsomal and hepatocyte incubations. The structures of these metabolites were confirmed by comparison with synthetic standards. Hydroxylation occurred on the A-ring of 4′ - bromoflavone but not on the B-ring, probably due to deactivation of the B-ring by bromine. No phase II metabolites were detected following incubation of 4′-bromoflavone in these in vitro systems. 4. In conclusion, these studies predict that 4′-bromoflavone should show moderate oral bioavailability, and that it would probably be excreted as unchanged compound and monohydroxylated metabolites. The results might be helpful in the design of clinical trials and in the interpretation of pharmacokinetic studies of 4′-bromoflavone. [ABSTRACT FROM AUTHOR]