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In order to understand the pollution status of metals in the riparian soils along the Wujiang River, 26 sampling sites in the mainstream and tributary streams were selected for investigation. The geo-accumulation index (Igeo), Nemerow integrated pollution index, and potential ecological risk index were applied to evaluate the contamination status and ecological risks of metals. Results revealed that the average concentrations of As, Cd, Cr, Cu, Mn, Ni, Pb, and Zn were 12.20, 0.51, 84.01, 57.42, 922.57, 38.37, 38.06, and 127.82 mg/kg, respectively. The metal contamination degree and ecological risks in the upper reaches were significantly higher than those in the middle and lower reaches of the Wujiang River. Cd was the dominant contamination metal. Significant non-carcinogenic and carcinogenic risks of metals were found in children based on the hazard index and carcinogenic risk. As was the main non-carcinogenic and carcinogenic pollutant metal in both adults and children. According to principal component analysis, hierarchical clustering analysis, and absolute principal component scores-multiple linear regression, anthropogenic sources (mining and agricultural activities) contributed most to Zn, Pb, Cr, Cd, Cu, and Ni, with contribution rates of 89.14, 82.32, 74.46, 72.12, 68.52, and 61.02%, respectively. Natural sources contributed most to Mn, with a contribution rate of 83.07%. Unidentified sources contributed most to As, with a contribution rate of 47.27%. [ABSTRACT FROM AUTHOR]

As a biodegradable polyester, the commercialized synthesis protocol of poly(ε-caprolactone) (PCL) under mild conditions is of great significance and attractive. Herein, the ring-opening polymerization (ROP) of ε-caprolactone (ε-CL) using FeCl3 catalyst and benzyl alcohol (BnOH) as the initiator was developed. FeCl3 has been proved to be an efficient catalyst for the ROP of ε-CL under mild conditions. The conversion of ε-CL to PCL was 98.8% at 60 °C within 4 h, with number-average molecular weight (Mn) and dispersity (PDI) of 1.65 × 104 g/mol and 1.28, respectively. Moreover, a coordination-insertion ring-opening polymerization mechanism mediated by FeCl3 was proposed. Overall, this work is expected to provide a feasible industrial method for the preparation of PCL from the direct aerobic oxidation of cyclohexanone. [ABSTRACT FROM AUTHOR]

Electropulsing treatment (EPT), as an external field technology, has the potential to adjust the crystallization of mold flux when it is locally applied in the casting mold. In this study, the effect of EPT with different pulse duty cycles on crystallization behavior of calcium silicate-based mold flux was investigated. The results show that the morphology of crystals precipitated in the mold flux transforms from elongated grains into block-like grains, with the average grain radius increasing from 14.1 ± 1.01 μm to 24.7 ± 2.07 μm when the duty cycle increases from 10% to 70%. Phase analyses show that the fraction of Ca2Mg0.75Al0.5Si1.75O7 in the mold flux increases from 11.2 wt.% to 14.7 wt.%, while that of Ca4Si2O7F2 decreases from 88.8 wt.% to 85.3 wt.% with the increase of the duty cycle. The variation of content of these phases is mainly due to their electrical conductivity, which leads to the enhancement of melilite and the inhibition of cuspidine precipitation when the electropulsing is applied. [ABSTRACT FROM AUTHOR]

In order to assess the bioaccumulation and health risk of metals in a river reservoir, concentrations of copper (Cu), zinc (Zn), lead (Pb), cadmium (Cd), arsenic (As), and mercury (Hg) in the water, sediments, two small-sized fish, and a freshwater mussel from the Zhoubai reservoir were examined. The results indicated that all of these metals conform with class one of environmental quality standards for surface water (State Environmental Protection Administration of China, GB 3838–2002). There were no significant differences for total metal concentrations in sediment between the three sampling sites (p > 0.05), but the bioavailable concentrations in S3 were the lowest. The Cd was dominated with exchangeable fraction and showed considerable risk. All metal concentrations except for Pb in Rhodeus sinensis were significantly higher than those in Ctenogobius giurinus (p < 0.05). The metal concentrations in Cristaria plicata showed a similar pattern of bioavailable metals in sediment, indicating that the metal concentrations in aquatic organisms were determined by the bioavailable forms of metals. Negative correlations were observed between the size of fish and concentrations of Cu, Zn, Pb, Cd, and As. However, significant positive correlations were found between the size of mussel and concentrations of Cd (p < 0.01), As (p < 0.05), and Hg (p < 0.01). Zn had the highest BCF values in fish and mussel. The aquatic organisms showed lower ability of metal bioaccumulation from the sediment. Low values of target hazard quotient (THQ), hazard index (HI), and carcinogenic risk (CR) indicated that these metals do not pose a health risk to public through fish and mussel consumption in this study area. [ABSTRACT FROM AUTHOR]

Changes of fluid speed may cause large vibrations in the pipe system. Generally, the fluid speed in a pipe system may not be constant all the time but has an oscillating property of the fluid, such as pulsating fluid. When a pipe conveys pulsating fluid, its dynamic response is significantly affected by the fluid. This paper investigates the vibration characteristics of a pipe conveying pulsating fluid with nonlinear supports at both ends. Based on the Hamilton principle, the governing equations and the boundary conditions for the pipes conveying pulsating fluid are determined. The multi-scale method combined with the modal revision method is introduced to obtain the approximate analytical results of the system steady-state response. Subsequently, the approximate analytical solution is verified numerically by the differential quadrature element method. The effects of the linear support stiffness, the nonlinear support stiffness, the fluid speed, and the viscoelastic coefficient on the stability boundary of parametric resonance are investigated. The effects of system parameters on steady-state responses of the pipe are also discussed in detail. The results reveal that the two methods are in good agreement. And it is shown that the linear support stiffness affects not only the parametric resonance amplitude but also the resonance region, while the nonlinear support stiffness only affects the parametric resonance amplitude, but not the resonance region. [ABSTRACT FROM AUTHOR]

In this study, polyvinyl butyral (PVB) was used as raw material, combined with electrospinning and microperforation process to prepare micro-/nanofiber membranes with excellent low-frequency sound absorption performance. To comprehensively explore the influence mechanisms of fiber diameter, multi-layer structure, and microperforated structure on the sound absorption performance, experiment and theoretical analysis were both conducted. Experimental results showed that appropriately reducing the fiber diameter, increasing the number of PVB membrane layers, and setting microperforated structure and cavity could improve the sound absorption performance in the low-frequency range. By adjusting the number of layers and the microperforation structure, the effective sound absorption band range of the fiber membrane can also be adjusted to better meet the sound absorption requirements. When the number of fiber layers was 20, the perforation rate was 1%, the perforation diameter was 0.6 mm, and the cavity depth was 40 mm, the PVB fiber membrane had peaks of 0.8483 and 0.9792 at 350 Hz and 480 Hz, respectively. Theoretical analysis showed that the acoustic electrical analogy model can well predict the resonance frequency and sound absorption peak of fiber membrane, and proved that microporous fiber membrane had both porous and resonant sound absorption mechanisms. These lightweight fiber membranes have great potential for application in sound absorption, such as in transportation, construction, and instrumentation. [ABSTRACT FROM AUTHOR]

In order to assess the metal pollution in the Wujiang River, concentrations of Cu, Zn, Fe, Mn, Pb, Cd, As, and Hg in the water, sediments, and two fish species Cyprinus carpio and Pelteobagrus fulvidraco from the middle reaches (Tuomugang, TMG) and lower reaches (Wulong, WL) of the Wujiang River were examined. The results indicated that all metal concentrations were lower than the values for grade one water quality according to the Environment Quality Standard for Surface Water of China (GB 3838–2002). The bioavailable fraction concentrations of Zn, Fe, Mn, Pb, and Hg in WL were significantly higher than those in TMG (p < 0.05), indicating that these metals in sediments of WL have higher bioavailability and mobility. The Cu, Zn, Fe, Pb, As, and Hg were mainly related to the residual fraction, while the Mn and Cd were mainly associated with the non-residual fraction. The risk assessment code (RAC) and the secondary phase to the primary phase (RSP) values indicated that Mn and Cd have a high risk of secondary release. The mean metal concentrations in the liver of the two fish species were higher than those in muscle. The higher metal concentrations of fish in WL suggested that bioaccumulation of metals in fish could be influenced by metal bioavailability. No identical relationships between metal concentrations and fish length were manifested in the present study. The values of target hazard quotient (THQ) and hazard index (HI), and carcinogenic risk (CR) of metals for the consumption of C. carpio and P. fulvidraco indicated that the anglers would likely not experience significant non-carcinogenic risk, but the carcinogenic risk of As cannot be ignored. Thanks to prohibited commercial fishing in the Wujiang River, the metal pollution will probably not pose a health risk to the general public for wild fish consumption. [ABSTRACT FROM AUTHOR]

This work aims to obtain efficient sound absorbing materials in the low and middle frequency. Jute fiber and polypropylene were used to prepare a kind of composite material by mixing-hot pressing process. On this basis, micro-perforated composite materials with various perforation characteristics were fabricated. The effect of drilling diameter, punching ratio, thickness and cavity depth on its acoustic performance was studied. The acoustic-electric analogy model and transfer matrix method of the micro-perforated plate were introduced for analyzing the agreement between the theoretical value and the corresponding experimental results. It was found that the jute fiber reinforced polypropylene microperforated composite had good sound absorbing ability at the low and middle frequencies, and thus had obvious advantages compared with the traditional sound absorption materials. In addition, by properly adjusting the structural parameters, the materials can absorb broadband noise in different frequency ranges to meet diversified needs. Yet with such natural advantages, the microperforated composite we prepared could be promising alternatives in the noise reduction field. [ABSTRACT FROM AUTHOR]

The axial fluid-induced vibration of pipes is very widespread in engineering applications. The nonlinear forced vibration of a viscoelastic fluid-conveying pipe with nonlinear supports at both ends is investigated. The multi-scale method combined with the modal revision method is formulated for the fluid-conveying pipe system with nonlinear boundary conditions. The governing equations and the nonlinear boundary conditions are rescaled simultaneously as linear inhomogeneous equations and linear inhomogeneous boundary conditions on different time-scales. The modal revision method is used to transform the linear inhomogeneous boundary problem into a linear homogeneous boundary problem. The differential quadrature element method (DQEM) is used to verify the approximate analytical results. The results show good agreement between these two methods. A detailed analysis of the boundary nonlinearity is also presented. The obtained results demonstrate that the boundary nonlinearities have a significant effect on the dynamic characteristics of the fluid-conveying pipe, and can lead to significant differences in the dynamic responses of the pipe system. [ABSTRACT FROM AUTHOR]

Textile-based supercapacitors are promising flexible energy storage device that can provide stable power supply for wearable electronic devices. Herein, solid-state textile-based coplanar supercapacitors have been prepared by utilizing the cost-effective multi-walled carbon nanotubes (MWCNTs) as integrated electrodes and current collectors. The integrated electrodes are fabricated with facile screen-printing process and show great potential of mass production. By optimizing the concentration of MWCNTs ink, porous and uniform conductive electrode network is formed on fabric substrate, which provide more active sites for electrolyte ions adsorption. The textile-based coplanar supercapacitors show great capacitive behavior and gravimetric specific capacitance of 26.4 F g−1 at scan rate of 10 mV s−1. Moreover, there is no significant change on the electrochemical performance of textile-based coplanar supercapacitor under dynamically bending with relatively high strain rate of 20% s−1, which demonstrates excellent flexibility and electrochemical stability. It provides an important strategy for the large-scale application and development of flexible supercapacitors. [ABSTRACT FROM AUTHOR]

External fields, such as magnetic and electric, are applied to the continuous casting mold to improve the quality of casting products. The performance of the mold flux should also be impacted when these external fields are applied in the mold. The extent of the impact is associated with the electrical conductivity. So, in this study, the electrical conductivity of the mold fluxes with various basicity was measured using the AC four-electrode method. The results show that the electrical conductivity of the mold flux increased while its activation energy decreased with the increase of basicity from 0.8 to 1.1, at 1423 K to 1573 K. In addition, the analyses of Fourier-transform infrared (FTIR) and Raman spectroscopies show that the complex structural units, such as Q3(Si), Si–O–Si, Si–O–Al, and Al–O0, reduced with the increase of basicity. So the melt structure of the mold flux was simplified by the addition of CaO and reduction of SiO2. From the variations of electrical conductivity and melt structure, it can be concluded that it is due to the simplification of melt structures of the mold flux by the increase of basicity, which promotes the diffusion of ions/ionic groups, and then leads to the increase of electrical conductivity. [ABSTRACT FROM AUTHOR]

In this work, the Hofmeister effects of nine kinds of anions at different concentrations on the lower critical solution temperature (LCST) of the macroporous thermo-responsive poly(N-isopropylacrylamide) grafted poly(vinyl alcohol) formaldehyde (PVF-g-PNIPAM) hydrogels are investigated with differential scanning calorimetry (DSC). Four kinds of anions with strong hydration, including CO32–, SO42–, S2O32–, and F–, and four kinds of anions with weak hydration, including Br–, NO3–, I–, and ClO4–, and Cl– as a medium anion are systematically studied and found to demonstrate the effects of the residual hydroxyl groups and network structure of PVF on the LCST values of PVF-g-PNIPAM hydrogels in comparison with that of neat PNIPAM. On the one hand, the existence of hydroxyl groups on PVF backbone promotes the solubility of grafted PNIPAM due to their hydrophilicity and hydrogen-bond interactions with water. On the other hand, the network structure of as-prepared samples restricts free movements of grafted PNIPAM chains, which results in the increase of LCST values. In addition, the difference of grafting percentage also influences the variation of LCST values of PVF-g-PNIPAM hydrogels under salt concentration. [ABSTRACT FROM AUTHOR]

Purpose: The aims of this study were to investigate the composition of clay minerals in soils derived from different parent materials and to elucidate how parent materials and pedogenic environment affect the distribution of clay minerals and reveal the implications for pedogenetics and taxonomy in Stagnic Anthrosols. Materials and methods: Clay mineralogy and physicochemical properties of the Hydragric horizon of Stagnic Anthrosols derived from granite (GR), plate shale (PS), quaternary red clays (QRC), limestone (LS), purple sandy shale (PSS) and fluvial-lacustrine deposit (FLD) located in Hunan Province of China were analysed to explore the relationships between the conditions influencing the formation of the soil and the composition of clay minerals. Results and discussion: Results indicated that the composition of clay minerals is closely related to both parent material and type of Stagnic Anthrosols: the soils derived from GR, PS and QRC, which are mostly classified as Fe-accumulic-Stagnic Anthrosols, are dominantly 1:1 type kaolinite and vermiculite and illite/vermiculite mixed layer minerals of widespread distribution. However, soils derived from LS, PSS and FLD were mainly classified as Hapli-Stagnic Anthrosols and are mainly composed of 2:1 type illite/smectite mixed layer minerals, where chlorite is commonly found. Illite is widely distributed and its content varies the least among different parent materials. An extremely significant relationship between pH and kaolinite, chlorite and mixed layer minerals was noted, and the two kinds of mixed layer minerals showed highly significant negative correlation. Conclusions: This study revealed that the types and quantities of clay minerals in the soil are closely related to the types of parent material. This reflected better direction and degree of development in Stagnic Anthrosols, which is related to the physicochemical properties of parent material and can be used as one of the bases for the classification of soil groups and subgroups within the soil family for Stagnic Anthrosols in Chinese Soil Taxonomy. [ABSTRACT FROM AUTHOR]

Arabidopsis AGAMOUS (AG) has roles in specifying reproductive organ (stamens and carpels) identity, floral meristem determinacy, and repression of A-function. To investigate possible roles of AG orthologous genes in gymnosperm species and evolution of C function, we isolated and identified AG orthologous gene TcAG from Taxus chinensis var. mairei (family Taxaceae, order Coniferales), a member of the last divergant lineage from higher Conifer that sisters to Gnetales. Sequence alignment and phylogenetic analysis grouped TcAG into the gymnosperm AG lineage. TcAG was expressed in both developing male and female cones, but there was no expression in juvenile leaves. Ectopic expression of TcAG in an Arabidopsis ag mutant produced flowers with the third whorl petaloid stamen and fourth whorl normal carpel, but failed to convert first whorl sepals into carpeloid organs and second whorl petals into stamenoid organs. A 35S::TcAG transgenic Arabidopsis ag mutant had very early flowering, and produced a misshapen inflorescence with a shortened floral axis. Our results suggest that establishment of the complete C-function occurred gradually during AG lineage evolution even in gymnosperms. [ABSTRACT FROM AUTHOR]

Thermal degradation behaviors and fire retardant properties of poly(1,3,4-oxadiazole)s (POD) and poly(m-phenylene isophthalamide) (PMIA) fibers were investigated. The thermal gravimetric analysis (TGA) demonstrated that POD exhibited higher onset thermal degradation temperature (T) than PMIA, exceeding nearly 80 °C. The thermal degradation kinetics, evaluated by the modified Coats-Redfern method, displayed that the apparent activation energy (E) of POD and PMIA fibers was similar when the conversion rate ( α) ranges from 0.2 to 0.5, while with the α from 0.6 to 0.8, the E of POD was significantly lower than that of PMIA. The fire retardant performance of POD and PMIA fibers were evaluated by cone calorimeter under heat fluxes of 35, 50 and 75 kW/m, during which the temperature of the fibers were monitored by a thermocouple. Surprisingly, POD fibers showed inferior fire retardant performance in comparison with PMIA, with lower time to ignition (TTI) and higher peak heat release rate (PHRR). The origin of the different fire retardant properties of both fibers was revealed by analyzing the residual chars and gaseous products during thermal pyrolysis. The morphology confirmed that stable and compact chars can be formed in PMIA. In addition, the Fourier Transform Infrared Spectroscopy (FTIR) characterization of the residual char revealed that POD can form carbonaceous chars at the heat flux of 50 kW/m, while the heat flux of PMIA was 75 kW/m. The pyrolysis products characterized by pyrolysis-gas chromatography-mass spectrometry (Py-GC-MS) indicated that POD can be pyrolyzed completely at 600 °C, while the temperature of PMIA was 700 °C. [ABSTRACT FROM AUTHOR]

A miniature high-resolution omnidirectional gaze optical imaging system comprising one optical low-pass filter and 5 lens elements with just one aspheric surface was successfully designed. The total tracking length of the system is 14.7 mm and fit on a 5MPx 2/3in CCD with 2448 × 2050 pixel of 3.45 μm for the full 360° × 200° imaging. We introduced the difficulties in the design of ultrawide field of view system and proposed specific computations to overcome them by aberration theories, furthermore making a simulated analysis and performance evaluation using ZEMAX optical design software. The result shows that an admirable corrected field curvature along with a low F-theta distortion, and a perfect lateral and longitudinal color aberration correction were achieved; relative illumination of all field is over 68%; when the ambient temperature changes from −40 to 70 ℃, the modulation transfer function performs in a steady range at 75 lp/mm; all of these will promote the wide-field lens application in medical, automotive, and stereo vision. [ABSTRACT FROM AUTHOR]

This paper presents a review on dip-coating for fibrous materials, mainly concentrated on the mechanism, recently developed dip-coating methods and novel functional applications. The emphasis has been made here, to present theoretical basis of dip-coating-induced film deposition, especially, the reported works to predict the thickness based on various processing parameters. Different modified dip-coating techniques to fabricate deposited films for fibrous substrate have also been gathered. The scope of reviewed dip-coating methods are not only conventional solution and sol-gel-based dip-coating, but also recently developed vacuum-assisted, spin-assisted, photo-assisted and multi-layered dip-coating methods. An overview of reported and potential applications for coated fibrous materials has also been given, which mainly including self-cleaning, oil-water separation, conductive textiles, fibrous-based energy storage devices, and photonic crystals, etc. This review is intended to give readers a good horizon for the present status concerning variety of studies and applications related to dip-coating. An effort has been made here to report the important contributions in the area of dip-coating for fibrous substrate, and critical points regarding future research directions are outlined in the summary. Graphical Abstract: [ABSTRACT FROM AUTHOR]

Background/Introduction: Robot localization can be considered as a cognition process that takes place during a robot estimating metric coordinates with vision. It provides a natural method for revealing the true autonomy of robots. In this paper, a kernel principal component analysis (PCA)-regularized least-square algorithm for robot localization with uncalibrated monocular visual information is presented. Our system is the first to use a manifold regularization strategy in robot localization, which achieves real-time localization using a harmonic function. Methods: The core idea is to incorporate labelled and unlabelled observation data in offline training to generate a regression model smoothed by the intrinsic manifold embedded in area feature vectors. The harmonic function is employed to solve the online localization of new observations. Our key contributions include semi-supervised learning techniques for robot localization, the discovery and use of the visual manifold learned by kernel PCA and some solutions for simultaneous parameter selection. This simultaneous localization and mapping (SLAM) system combines dimension reduction methods, manifold regularization techniques and parameter selection to provide a paradigm of SLAM having self-contained theoretical foundations. Results and Conclusions: In extensive experiments, we evaluate the localization errors from the perspective of reducing implementation and application difficulties in feature selection and magnitude ratio determination of labelled and unlabelled data. Then, a nonlinear optimization algorithm is adopted for simultaneous parameter selection. Our online localization algorithm outperformed the state-of-the-art appearance-based SLAM algorithms at a processing rate of 30 Hz for new data on a standard PC with a camera. [ABSTRACT FROM AUTHOR]

Trabala vishnou gigantina Yang (Lepidoptera: Lasiocampidae) is a major pest that damages the sea-buckthorn, Hippophae rhamnoides. We observed and compared the feeding preferences of T. vishnou gigantina larvae on six sympatric plant species in a two-choice test. We also compared T. vishnou gigantina fitness, as measured by the following variables: larvae weight, developmental period, pupae versus adult weight, longevity, and fecundity rates. Between host and non-host plants, larvae showed a strong preference for their natural host (sea-buckthorn), followed by apricot, poplar, and willow. Caragana and locust were the least preferred plants when the natural host plant was not present. Larvae reared on sea-buckthorn possessed greater pre-pupal weight, had lower mortality, and developed more quickly into heavier pupae than either poplar-raised or willow-raised larvae. Fecundity was highest on sea-buckthorn, second highest on apricot, and lowest on poplar. Longevity (of both females and males) was not significantly different across plant species. These results clearly demonstrate that T. vishnou gigantina larvae are able to distinguish between host versus non-host plants, and that their preference translates to increased fitness. Possible, non-mutually exclusive explanations for observed preference and fitness differences include variation in required nutritional content across plant species or the presence of plant traits (morphological features or chemical metabolites) that negatively affect larval development. While the exact mechanisms are unknown, these data may be useful for the development of appropriate counter-measures to the damage caused by T. vishnou gigantina on sea-buckthorn. [ABSTRACT FROM AUTHOR]

In this work, monodisperse giant polymersomes are fabricated by dewetting of water-in-oil-in-water double emulsion droplets which are assembled by amphiphilic block copolymer molecules in a microfluidic device. The dewetting process can be tuned by solvation between solvent and amphiphilic block copolymer to get polymersomes with controllable morphology. Good solvent (chloroform and toluene) hinders dewetting process of double emulsion droplets and gets acornlike polymersomes or patched polymersomes. On the other hand, poor solvent (hexane) accelerates the dewetting process and achieves complete separation of inner water phase from oil phase to form complete bilayer polymersomes. In addition, twin polymersomes with bilayer membrane structure are formed by this facile method. The formation mechanism for different polymersomes is discussed in detail. [ABSTRACT FROM AUTHOR]

An investigation was carried out to study the influences of basicity and LiO on the melting, crystallization, and heat transfer behavior of Fluorine-free mold flux designed for the casting of medium carbon steels using double hot thermocouple technology and infrared emitter technique. The results showed that with the addition of basicity, the melting and crystallization temperatures of the mold fluxes were increased, and the final heat transfer rate was reduced, as the basicity tends to promote the crystallization behavior of the designed mold fluxes. Besides, with the increase of LiO content in the mold flux, the melting and crystallization temperature decreased, as the LiO tends to inhibit the formation of high melting temperature crystal and lower the system melting temperature zone; meanwhile the crystallization capability of the mold flux was enhanced in the low-temperature region. Moreover, the results of EDS and XRD were confirmed that the main crystal phase in the Fluorine-free mold fluxes is calcium borate silicate (CaSiBO). Those results obtained can provide guidelines for the design of new Fluorine-free mold flux for the casting medium carbon steels. [ABSTRACT FROM AUTHOR]

Zinc induces protein phosphatase 2A (PP2A) inactivation and tau hyperphosphorylation through PP2A (tyrosine 307) phosphorylation in cells and the brain, but whether Zn has a direct inhibitory effect on PP2A is not clear. Here we explored the effect of Zn on PP2A and their direct interaction in vitro. The results showed that Zn mimicked the inhibitory effect of okadaic acid on protein phosphatase and prevented tau dephosphorylation in N2a cell lysates. PP2A activity assays indicated that a low concentration (10 μmol/L) of Zn inhibited PP2A directly. Further Zn-IDA-agarose affinity binding assays showed that Zn bound to and inhibited PP2Ac but not PP2Ac or PP2Ac. Taken together, Zn inhibits PP2A directly through binding to PP2Ac in vitro. [ABSTRACT FROM AUTHOR]

Porous polymer beads (PPBs) containing hierarchical bimodal pore structure with gigapores and meso-macropores were prepared by polymerization-induced phase separation (PIPS) and emulsion-template technique in a glass capillary microfluidic device (GCMD). Fabrication procedure involved the preparation of water-in-oil emulsion by emulsifying aqueous solution into the monomer solution that contains porogen. The emulsion was added into the GCMD to fabricate the (water-in-oil)-in-water double emulsion droplets. The flow rate of the carrier continuous phase strongly influenced the formation mechanism and size of droplets. Formation mechanism transformed from dripping to jetting and size of droplets decreased from 550 μm to 250 μm with the increase in flow rate of the carrier continuous phase. The prepared droplets were initiated for polymerization by on-line UV-irradiation to form PPBs. The meso-macropores in these beads were generated by PIPS because of the presence of porogen and gigapores obtained from the emulsion-template. The pore morphology and pore size distribution of the PPBs were investigated extensively by scanning electron microscopy and mercury intrusion porosimetry (MIP). New pore morphology was formed at the edge of the beads different from traditional theory because of different osmolarities between the water phase of the emulsion and the carrier continuous phase. The morphology and proportion of bimodal pore structure can be tuned by changing the kind and amount of porogen. [ABSTRACT FROM AUTHOR]

An easy method is presented to fabricate monodisperse magnetic macroporous polymer beads (MMPBs). Waterin- oil high internal phase emulsion (HIPE) is prepared by emulsifying aqueous iron ions solution in an oil phase containing monomers. The HIPE is introduced into a simple microfluidic device to fabricate monodisperse (water-in-oil)-in-water double emulsion droplets. The droplets serve as microreactors to synthesize FeO nanoparticles and are on-line polymerized to form MMPBs. The prepared MMPBs display uniform size, interconnected porous structure, superparamagnetic behavior and uniform distribution of FeO in polymer matrix. The MMPBs are characterized by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM). We believe that this method is a universal technique in preparing macroporous nanocomposite beads. [ABSTRACT FROM AUTHOR]

The article presents information on a study conducted on the isolation of gamma-lactone derivatives and terpenoids from the plant Selaginella uncinata. Other compounds, including viburnolide A, dehydrololiolide, and trans-abscisic acid were also isolated from the Selaginella genus. Selaginella uncinata is a traditional plant medicine with anti-anoxic effects, and it is used for the treatment of jaundice, rheumatism, dysentery, and edema.

Laughter frequently occurs in spontaneous speech (e.g. conversational speech, meeting speech). Detecting laughter is quite important for semantic analysis, highlight extraction, spontaneous speech recognition, etc. In this paper, we first analyze the characteristic differences between speech and laughter, and then propose an approach for detecting laughter in spontaneous speech. In the proposed approach, non-silence signal segments are first extracted from spontaneous speech by using voice activity detection, and then split into syllables. Afterward, the possible laughter bouts are constructed by merging adjacent syllables (using symmetrical Itakura distance measure and duration threshold) instead of using a sliding fixed-length window. Finally, hidden Markov models (HMMs) are used to recognize the possible laughter bouts as laughs, speech sounds or other sounds. Experimental evaluations show that the proposed approach can achieve satisfactory results in detecting two types of audible laughs (audible solo and group laughs). Precision rate, recall rate, and F1-measure (harmonic mean of precision and recall rate) are 83.4%, 86.1%, and 84.7%, respectively. Compared with the sliding-window-based approach, 4.9% absolute improvements in F1-measure are obtained. In addition, the laughter boundary errors obtained by the proposed approach are smaller than that obtained by the sliding-window-based approach. [ABSTRACT FROM AUTHOR]

Vascular endothelial growth factor (VEGF) is best known as an angiogenic factor essential for embryonic vasculogenesis and postnatal angiogenesis. Considerable evidence has accumulated that VEGF also has non-angiogenic functions. Early studies demonstrated that VEGF transcripts are ubiquitously expressed, and the phosphorylation of VEGF receptor is detectable in adult organs that have no feature of angiogenesis. Recent clinical studies showed that the inhibition of VEGF signaling results in diverse angiogenesis-irrelevant side effects involving the dysfunctions of many organs, suggesting non-angiogenic roles of VEGF in the regulation of organ homeostasis. On the other hand, VEGF stimulates endothelial cells (ECs) to express intercellular adhesion molecules that mediate physical interactions with adjacent tissue cells, or secreted various multifunctional substances that affect the functions of surrounding organs. Furthermore, very recent studies including ours have revealed VEGF as a potent agonist for endothelial exocytosis of Weibel-Palade bodies in which thrombogenic and inflammatory factors are stored. In this brief review, we highlight the importance of VEGF non-angiogenic functions in the modulation of tissue repair and organ regeneration, vascular homeostasis, and inflammation, and propose that the non-angiogenic functions are primarily mediated through the substances released from ECs. [ABSTRACT FROM AUTHOR]

Wireless sensor networks (WSNs) are often deployed in harsh environments. Thus adversaries can capture some nodes, replicate them and deploy those replicas back into the strategic positions in the network to launch a variety of attacks. These are referred to as node replication attacks. Some methods of defending against node replication attacks have been proposed, yet they are not very suitable for the mobile wireless sensor networks. In this paper, we propose a new protocol to detect the replicas in mobile WSNs. In this protocol, polynomial-based pair-wise key pre-distribution scheme and Counting Bloom Filters are used to guarantee that the replicas can never lie about their real identifiers and collect the number of pair-wise keys established by each sensor node. Replicas are detected by looking at whether the number of pair-wise keys established by them exceeds the threshold. We also derive accurate closed form expression for the expected number of pair-wise keys established by each node, under commonly used random waypoint model. Analyses and simulations verify that the protocol accurately detects the replicas in the mobile WSNs and supports their removal. [ABSTRACT FROM AUTHOR]

small-volume fiber-optic pH sensor (FOEWS) based on evanescent wave excitation is developed and evaluated. The sensor is simply fabricated by inserting a decladded optical fiber into a transparent capillary tube. A microchannel between the optical fiber and the capillary inner wall was formed and acted as flow cell for solution flowing through. The pH-sensitive fluorophore of fluorescein can be excited by the evanescent wave field produced on the fiber core surface to produce emission fluorescence. pH value was then sensed by its enhancing effect on the emission fluorescence intensity. The response range of the sensor is from pH 2.09 to pH 8.85 and the linear range is from pH 3.25 to 8.85. The proposed sensor has a small detection volume of 2.5 μL and a short response time of 8 s. It has been applied to measure pH values of real water samples and was in good agreement with the results obtained by commercial pH meter. [ABSTRACT FROM AUTHOR]

Trastuzumab is a successful rationally designed ERBB2-targeted therapy. However, about half of individuals with ERBB2-overexpressing breast cancer do not respond to trastuzumab-based therapies, owing to various resistance mechanisms. Clinically applicable regimens for overcoming trastuzumab resistance of different mechanisms are not yet available. We show that the nonreceptor tyrosine kinase c-SRC (SRC) is a key modulator of trastuzumab response and a common node downstream of multiple trastuzumab resistance pathways. We find that SRC is activated in both acquired and de novo trastuzumab-resistant cells and uncover a novel mechanism of SRC regulation involving dephosphorylation by PTEN. Increased SRC activation conferred considerable trastuzumab resistance in breast cancer cells and correlated with trastuzumab resistance in patients. Targeting SRC in combination with trastuzumab sensitized multiple lines of trastuzumab-resistant cells to trastuzumab and eliminated trastuzumab-resistant tumors in vivo, suggesting the potential clinical application of this strategy to overcome trastuzumab resistance. [ABSTRACT FROM AUTHOR]

The epithelial-mesenchymal transition (EMT) has recently been linked to stem cell phenotype. However, the molecular mechanism underlying EMT and regulation of stemness remains elusive. Here, using genomic approaches, we show that tumour suppressor p53 has a role in regulating both EMT and EMT-associated stem cell properties through transcriptional activation of the microRNA miR-200c. p53 transactivates miR-200c through direct binding to the miR-200c promoter. Loss of p53 in mammary epithelial cells leads to decreased expression of miR-200c and activates the EMT programme, accompanied by an increased mammary stem cell population. Re-expressing miR-200c suppresses genes that mediate EMT and stemness properties and thereby reverts the mesenchymal and stem-cell-like phenotype caused by loss of p53 to a differentiated epithelial cell phenotype. Furthermore, loss of p53 correlates with a decrease in the level of miR-200c, but an increase in the expression of EMT and stemness markers, and development of a high tumour grade in a cohort of breast tumours. This study elucidates a role for p53 in regulating EMT-MET (mesenchymal-epithelial transition) and stemness or differentiation plasticity, and reveals a potential therapeutic implication to suppress EMT-associated cancer stem cells through activation of the p53-miR-200c pathway. [ABSTRACT FROM AUTHOR]

The erosion of west beach in Beidaihe has become severe in the recent years. In order to nourish the beach, four different engineering nourishment schemes are proposed. As a near shore project, wave is the main force in the sea area of west beach. Based on the information above, wave fields in the sea area of west beach under both ordinary wave condition (S, H s =0.7m, T=3.2s) and strong wave condition (NE, H s =1.5m, T=4.7s) are analyzed. The result shows that beach nourishment with two jetties and three submerged breakwaters protects the west beach most effectively. [ABSTRACT FROM AUTHOR]

Background and Aims: Cancer cells are thought to possess immune evasion properties due to FasL overexpression in many types of human tumors. In the present study, we set out to investigate the role of MAPK-ERK pathway in 67-kDa laminin receptor induced FasL expression and FasL-mediated apoptosis in human cholangiocarcinoma cells.Methods: The expression of FasL and its promoter activity in cultured cholangiocarcinoma cells were examined after treatment with laminin or transfection with plasmids containing siRNA targeted to 67-kDa laminin receptor. The effects of MAPK-ERK cascade inhibitor and c-Myc inhibition by siRNA on 67-kDa laminin receptor-induced FasL expression were determined. Apoptosis assay was performed to analyze the apoptosis of lymphocytes cocultured with cholangiocarcinoma cells treated with or without MAPK-ERK cascade inhibitor.Results: Our results revealed that the specific MAPK-ERK cascade inhibitor, PD98059, significantly attenuated phosphorylation of c-Myc on Ser-62 and FasL upregulation in QBC-939 cells and these cells showed decreased cytotoxicity against Fas-sensitive Jurkat T cells. A luciferase reporter assay revealed that FasL promoter activity was significantly reduced in cells treated with PD98059 or transfected with c-Myc siRNA.Conclusions: Based on these results, we conclude that 67LR induces FasL expression and cytotoxicity against Fas-sensitive Jurkat T cells in human cholangiocarcinoma cells through the phosphorylation of c-Myc on Ser-62 and the subsequent activation of the FasL promoter through the ERK pathway. [ABSTRACT FROM AUTHOR]

AbstractCholesterol efflux from lipid-loaded cells is a key athero-protective event that counteracts cholesterol uptake. The imbalance between cholesterol efflux and uptake determines the prevention or development of atherosclerosis. Many proteins and factors participate in the cholesterol efflux event. However, there are currently no systematic models of reverse cholesterol transport (RCT) that include most RCT-related factors and events. On the basis of recent research findings from other and our laboratories, we propose a novel model of one center and four systems with coupling transportation and networking regulation. This model represents a common way of cholesterol efflux; however, the systems in the model consist of different proteins/factors in different cells. In this review, we evaluate the novel model in vascular smooth muscle cells (VSMCs) and macrophages, which are the most important original cells of foam cells. This novel model consists of 1) a caveolae transport center, 2) an intracellular trafficking system of the caveolin-1 complex, 3) a transmembrane transport system of the ABC-A1 complex, 4) a transmembrane transport system of the SR-B1 complex, and 5) an extracelluar trafficking system of HDL/Apo-A1. In brief, the caveolin-1 system transports cholesterol from intracellular compartments to caveolae. Subsequently, both ABC-A1 and SR-B1 complex systems transfer cholesterol from caveolae to extracellular HDL/Apo-A1. The four systems are linked by a regulatory network. This model provides a simple and concise way to understand the dynamic process of atherosclerosis. [ABSTRACT FROM AUTHOR]

In this study, we investigated whether or not a new minimum contact locking compression plate (MC-LCP) can provide advantages over the limited contact dynamic compression plate (LC-DCP) in the context of interface contact area and force. Six matched pairs of cadaveric bones were used for each of three bone types of the humerus, radius and ulna. For each bone type, one of two bone plates was fixed to either of two matched cadaveric bones at the middle of the diaphysis. The interface contact area and force of the plate fixed to three types of human cadaveric bones were evaluated using Fuji prescale pressure sensitive film. Data were quantitated using computer-assisted image analysis. Results showed that the average force between the MC-LCP and humerus or radius was about half of that of the LC-DCP. And the average force between the MC-LCP and ulna was one third less than that of the LC-DCP. Meanwhile, the interface contact area between the MC-LCP and humerus or radius was also about half of that of the LC-DCP, and the interface contact area between the MC-LCP and ulna was less than one third of that of the LC-DCP. These results indicate that the MC-LCP has lower interface contact area and lower average force than that of the LC-DCP. Thus, the MC-LCP system may be a good alternate to treat forearm diaphyseal fractures. [ABSTRACT FROM AUTHOR]

Recently, learning to rank technology is attracting increasing attention from both academia and industry in the areas of machine learning and information retrieval. A number of algorithms have been proposed to rank documents according to the user-given query using a human-labeled training dataset. A basic assumption behind general learning to rank algorithms is that the training and test data are drawn from the same data distribution. However, this assumption does not always hold true in real world applications. For example, it can be violated when the labeled training data become outdated or originally come from another domain different from its counterpart of test data. Such situations bring a new problem, which we define as cross domain learning to rank. In this paper, we aim at improving the learning of a ranking model in target domain by leveraging knowledge from the outdated or out-of-domain data (both are referred to as source domain data). We first give a formal definition of the cross domain learning to rank problem. Following this, two novel methods are proposed to conduct knowledge transfer at feature level and instance level, respectively. These two methods both utilize Ranking SVM as the basic learner. In the experiments, we evaluate these two methods using data from benchmark datasets for document retrieval. The results show that the feature-level transfer method performs better with steady improvements over baseline approaches across different datasets, while the instance-level transfer method comes out with varying performance depending on the dataset used. [ABSTRACT FROM AUTHOR]

Feature subsets and hidden Markov model (HMM) parameters are the two major factors that affect the classification accuracy (CA) of the HMM-based classifier. This paper proposes a genetic algorithm based approach for simultaneously optimizing both feature subsets and HMM parameters with the aim to obtain the best HMM-based classifier. Experimental data extracted from three spontaneous speech corpora were used to evaluate the effectiveness of the proposed approach and the three other approaches (i.e. the approaches to single optimization of feature subsets, single optimization of HMM parameters, and no optimization of both feature subsets and HMM parameters) that were adopted in the previous work for discrimination between speech and non-speech events (e.g. filled pause, laughter, applause). The experimental results show that the proposed approach obtains CA of 91.05%, while the three other approaches obtain CA of 86.11%, 87.05%, and 83.16%, respectively. The results suggest that the proposed approach is superior to the previous approaches. [ABSTRACT FROM AUTHOR]

In the clinic, implant-associated infections are the chief risk facing orthopaedics and traumatology departments. Vancomycin-poly(D,L)-lactic acid (PDLLA) loaded plates were prepared by using solvent casting technology. The bacteriostatic activity to Staphylococcus aureus was evaluated in vitro. The biocompatibility of the plates was investigated by acute systemic toxicity test, haemolytic test, cytotoxicity test, etc. The in vitro inhibition test of Staphylococcus aureus showed that the plates had an inhibitory effect on Staphylococcus aureus. There was no toxicity for the vancomycin-PDLLA loaded plates. There was a good biocompatibility for the vancomycin-PDLLA loaded plates. These findings indicate that the plate maybe used to prevent or cure infection. [ABSTRACT FROM AUTHOR]

Cellulase activities of Anoplophora glabripennis (Motsch.) adults from two host plants ( Populus simonii × P. pyramidliscr cv. Opera Hsu. and Salix matsudana Koidz) fed on three different host tree species ( Acer negundo Linn., S. matsudana Koidz and P. simonii × P. pyramidliscr cv. Opera Hsu.) were investigated. Enzyme activities of endoglucanase and β-glucosidase in the intestines of the insects were measured. The results show that there are no statistically significant differences in the enzyme activities of endoglucanase between male and female insects from the two host plants fed on three host trees, neither in β-glucosidase. No statistically significant differences in the enzyme activities of endoglucanase and β-glucosidase were found between males and females from the two plants fed on three host tree species, except that the endoglucanase activity in males from the opera poplar fed on Hankow willow is lower than that fed on ash-leaf maple and opera poplar. [ABSTRACT FROM AUTHOR]

A fiber-optic sensor based on fluorescence quenching was designed for dissolved oxygen (DO) detection. The fluorinated xerogel-based sensing film of the present sensor was prepared from 3, 3, 3-tri-fluoropropyltrimethoxysilane (TFP--TriMOS). Oxygen-sensitive fluorophores of tris (2, 20- bipyridine) ruthenium (II) (Ru(bpy)32+) were immobilized in the sensing film and the emission fluorescence was quenched by dissolved oxygen. In the sensor fabrication, a two-fiber probe was employed to obtain the best fluorescence collection efficiency and the sensing film was attached to the probe end. Scanning electron microscope (SEM), UV--Vis absorption spectroscopy (UV--Vis) and fourier transform infrared spectroscopy (FTIR) measurements have been used to characterize the sensing film. The sensor sensitivity is quantified by Ideoxy/Ioxy, where Ideoxy and Ioxy represented the detected fluorescence intensities in fully deoxygenated and fully oxygenated environments, respectively. Compared with tetramethoxysilane (TMOS) and methyltriethoxysilane (MTMS)-derived sensing films, TFP--TriMOS-based sensor exhibited excellent performances in dissolved oxygen detection with short response time of 4 s, low limit of detection (LOD) of 0.04 ppm (R.S.D. = 2.5%), linear Stern--Volmer calibration plot from 0 to 40 ppm and long-term stability during the past 10 months. The reasons for the preferable performances of TFP--TriMOS-based sensing film were discussed. [ABSTRACT FROM AUTHOR]