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Biochar amendments could enhance retention of nutrients such as ammonium (NH4 + ), nitrate (NO3 - ), and phosphate (PO4 3-) in soils. However, the situation for sulphate (SO4 2-), which is an indispensable nutrient element for crop growth, is unclear. In this paper, the effects of biochar derived from rape (Brassica campesstris L.) straw at 600°C on the sorption and leaching of SO4 2- in light sierozem (Calcids) was studied in columns, where biochar amendment rate, column soil height, solution pH value and initial sulphate concentration were selected as factors. It is shown that the transport of sulphate was a significant non-equilibrium process and the sorption and leaching curves (SLCs) of sulphate were asymmetrical. The breakthrough time would be increased by increasing biochar amendment and soil column height, and by decreasing solution pH value and initial sulphate concentration. The SLCs of bromide trace were fitted to determine dispersion coefficient (D) using equilibrium convection dispersion equation (CDEeq). The non-equilibrium (two-site) model (CDEnon-eq) with the results from CDEeq was used to simulate the transport processes of sulphate in the soil column, with good fitness, using software CXTFIT 2.1 fitting. The results could supply an implication for biochar application in loess areas. [ABSTRACT FROM AUTHOR]

Soybean cyst nematode (Heterodera glycines) has become a serious risk for soybean production globally. Chemical nematicides pose a severe threat to human health and also pollute the environment whereas, biological control is a safe and eco-friendly method used to control pathogens. The aim of this study was to discover novel biocontrol agents against H. glycines by coating soybean seeds with biocontrol agent Sneb183 (Sinorhizobium fredii) and to assess its potential to control this pest. The stability and efficiency of Sneb183 (S. fredii) to control H. glycines in field and growth chamber experiments were investigated. Seed coating with Sneb183 significantly decreased the presence of H. glycines by 35.58%, 64.09% and 50.43% in experiments J2 (second-stage juveniles), J3 (third-stage juveniles) and J4 (fourthstage juveniles), respectively as compared to control. A progressive increase in the concentrations of the Snef183 resulted in a significant reduction of H. glycines. Additionally, Sneb183 boosted seed germination and seed vigor index. Moreover, seed coating with Sneb183 increased plant biomass. These results demonstrate that Sneb183 (S. fredii) is a promising biocontrol agent against H. glycine and biomass promoter of soybean. [ABSTRACT FROM AUTHOR]

Cyst-forming nematodes, a major category of plant parasitic nematodes, cause severe yield losses in many crop plants and are a serious threat to food production in China. However, the reports focused on identification of species abundance and distribution of cyst nematodes on main crops in China are fewer. During 2012-2014, nine populations of cyst nematodes collected from various locations in major crop cultivation areas of China were identified as four species (Heterodera glycines, H. avenae, H. filipjevi, H. elachista) based on morphology and molecular analysis. H. filipjevi and H. elachista were first discovered in Anhui and Jiangxi Provinces, respectively. In addition, a PCR-ITS-RFLP method was applied to distinguish all the studied populations, which revealed molecular characteristics of cyst nematode species on major field crops in China. The present study broadens the knowledge regarding distributions and molecular features of vital Heterodera species and populations, and will also provide useful information for early protection of cystnematodes in China. [ABSTRACT FROM AUTHOR]

Breast cancer is a leading cause of cancer death among women, and the failure of normal apoptosis has been proved in the development of breast cancer. The phytoestrogen, calycosin, is extracted from Chinese medical herb Radix astragali. We recently reported that calycosin successfully stimulated proliferation of ER-positive MCF-7 human breast cancer cells at low concentration. In the present study, we assessed the proapoptotic function of calycosin in MCF-7 cells at high concentration in vitro, as well as the possible mechanism of its effect. MCF-7 cells were treated with different concentrations of calycosin, and then detected by MTT assay for cellular viability, Hoechst assay, and fl ow cytometry for apoptosis. RASD1 is identified as a Ras-family member and a regulator in MAPK-mediated cascade leading to cell proliferation or apoptosis. To provide insight into the functions of RASD1 signaling pathway in calycosin-induced apoptosis, the expression of Bcl-2, Bax, and RASD1 in calycosin-treated cells were determined by Western blot assay. The results showed that high concentrations of calycosin significantly suppressed the proliferation of MCF-7 cells and promoted cell apoptosis. Moreover, compared with control group, the expression of Bcl-2 decreased with calycosin in MCF-7 cells, while Bax increased, which was significantly correlated with elevated expression of RASD1. Together, we present evidence that at relatively high concentration calycosin triggered cell apoptosis through the mitochondrial apoptotic pathway by upregulating RASD1. And for the first time, this study revealed that calycosin may have potential as a therapeutic agent for the treatment of breast cancer. [ABSTRACT FROM AUTHOR]

A triple-stimuli responsive polymer, poly(3-acrylamidophenylboronic acid)-b-poly(N-isopropylacrylamide) (PAAPBA-b-PNIPAM), has been synthesized by reversible addition-fragmentation chain transfer polymerization. Temperature, pH, and fructose induced micellization and dissociation transition of block copolymer was investigated by a combination of static and dynamic laser light scattering. PAAPBA-b-PNIPAM copolymer self-assembles into micelles with PAAPBA block as core and PNIPAM as shell in lower pH aqueous solution at room temperature. Increasing the temperature causes the micelle to shrink due to the dehydration of PNIPAM segments at pH 6.2. After the elevation of solution pH from 6.2 to 10.0, the increase in the hydrophilicity of PAAPBA block leads to an expulsion of unimers from micelles. In addition, the fructose addition further enhances the dissociation of micelles. Our experiments demonstrate that the micelle to unimer transition process proceeds via the step-by-step sequential expulsion of individual chains. [ABSTRACT FROM AUTHOR]

Owing to the superior dielectric property of aluminum oxide, precise patterning of self-assembled monolayers (SAMs) and nanoparticles (NPs) on aluminum oxide substrates is highly interesting for generating SAM- or NP-based electronic devices. This study employed nanoimprint lithography (NIL) and nanomolding in capillaries (NAMIC) for patterning ferromagnetic NPs on aluminum oxide substrates. We demonstrated the fabrication of structured arrays of various SAMs and NPs in micrometre and nanometre ranges. The polymer template generated by NIL behaved as a physical barrier and defined the pattern areas on the substrate. FePtAu NPs were assembled on phosph(on)ate SAM-modified polymer patterned substrates. After polymer removal, nano- and microscale line and dot NP patterns, with controlled layer thickness, were obtained on aluminum oxide substrates. Thick nanolines of NPs were obtained by NAMIC. PO3-terminated FePtAu NPs were assembled on alumina without need of a linker. The magnetic properties of the NPs were addressed by vibrating sample magnetometry and those of the patterned NPs by magnetic force microscopy. [ABSTRACT FROM AUTHOR]

This work investigates the capability of Raman spectroscopy (RS) to study the effects of ionizing radiation on single human tumour cells. Prostate tumour cells (cell line DU145) are cultured in vitro and irradiated to doses between 15 and 50 Gy with single fractions of 6 MV photons. Single-cell Raman spectra are acquired from irradiated and unirradiated cultures up to 5 days post-irradiation. Principal component analysis is used to distinguish the uniquely radiation-induced spectral changes from inherent sources of spectral variability arising from cell cycle differences and other known factors. We observe uniquely radiation-induced spectral changes which are correlated with both the irradiated dose and the incubation time post-irradiation. The spectral changes induced by radiation arise from biochemical differences in lipids, nucleic acids, amino acids and conformational protein structures between irradiated and unirradiated cells. To our knowledge, this study is the first use of RS to observe radiation-induced biochemical differences in single cells, and is the first use of vibrational spectroscopy to observe uniquely radiation-induced biochemical differences in single cells independent of concurrent cell-cycle- or cell-death-related processes. [ABSTRACT FROM AUTHOR]

Abstract  We revisit the empirical moving window filtering method of Swenson and Wahr (Geophys Res Lett 33:L08402, 2006) and its variants, Chambers (Geophys Res Lett 33:L17603, 2006) and Chen et al. (Geophys Res Lett 34: L13302, 2007), for reducing the correlated errors in the Stokes coefficients (SCs) of the spherical harmonic expansion of the GRACE determined monthly geopotential solutions. Based on a comparison of the three published approaches mentioned, we propose a refined approach for choosing parameters of the decorrelation filter. Our approach is based on the error pattern of the SCs in the monthly GRACE geopotential solutions. We keep a portion of the lower degree-order SCs with the smallest errors unchanged, and high-pass filter the rest using a moving window technique, with window width decreasing as the error of the SCs increases. Both the unchanged portion of SCs and the window width conform with the error pattern, and are adjustable with a parameter. Compared to the three published approaches mentioned, our unchanged portion of SCs and window width depend on both degree and order in a more complex way. We have used the trend of mass change to test various parameters toward a preferred choice for a global compromise between the removal of the correlated errors and the minimization of signal distortion. [ABSTRACT FROM AUTHOR]

Abstract  Efficiency of polymer light-emitting diodes (PLEDs) with poly(2-methoxy-5-(2-ethyl hexyloxy)-p-phenylene vinylene) (MEH-PPV) as an emitting layer was improved if a dehydrated nanotubed titanic acid (DNTA) doped hole-buffer layer polyethylene dioxythiophene (PEDOT) was used. Photoluminescence (PL) and Raman spectra indicated a stronger interaction between DNTA and sulfur atom in thiophene of PEDOT, which suppresses the chemical interaction between vinylene of MEH-PPV and thiophene of PEDOT. The interaction decreases the defect states in an interface region to result in enhancement in device efficiency, even though the hole transporting ability of PEDOT was decreased. [ABSTRACT FROM AUTHOR]

Abstract??In this paper, a variable heating strength model (VHS model) is developed to predict transient heat conduction from a vertical rod buried in a semi-infinite medium. Unlike past studies, the current VHS model permits a VHS along the rod. Both axial heat conduction through the rod and lateral heat conduction to the surrounding ground are modeled. A derived distribution of axial heating strength is then applied to a finite line heat source model to predict transient temperature changes in the surrounding medium. The predicted results show how the rod?s radius and ground?s thermal conductivity affect the vertical variation of heating strength and temperature response. Additional simulations predict the long-term temperature increase in the ground, due to a power transmission tower installed in a region of initially frozen ground. [ABSTRACT FROM AUTHOR]

To investigate the mechanisms leading to sustained thermoacoustic oscillations in swirl flames, a gas turbine model combustor was equipped with an optically accessible combustion chamber allowing the application of various laser techniques. The flame investigated was a swirled CH4/air diffusion flame (thermal power 10 kW, global equivalence ratio ϕ = 0.75) at atmospheric pressure which exhibited self-excited thermoacoustic oscillations at a frequency of 290 Hz. In separate experiments, the flow velocities were measured by laser Doppler velocimetry, the flame structures and heat release rates by planar laser-induced fluorescence of CH and by OH chemiluminescence, and the joint probability density functions of the major species concentrations, mixture fraction, and temperature by laser Raman scattering. All measurements were performed in a phase-locked mode, i.e., triggered with respect to the oscillating pressure level measured by a microphone. The results revealed large periodic variations of all measured quantities and showed that the heat release rate was correlated with the degree of mixing of hot products with unburned fuel/air mixtures before ignition. The thermal expansion of the reacting gases had, in turn, a strong influence on the flow field and induced a periodic motion of the inner and outer recirculation zones. The combination of all results yielded a deeper understanding of the events sustaining the oscillations in the flame under investigation. The results also represent a data base that can be used for the validation and improvement of CFD codes. [ABSTRACT FROM AUTHOR]

A mesoporous TiO2 precursor has been prepared by the hydrothermal condensation of tetrabutyltitanate in presence of an alkylamine template by three different methods. The surfactants were removed from as-synthesized TiO2 by calcination and solvent extraction methods. A potential photocatalyst, predominantly present as an anatase phase, was produced in the latter case. The samples were characterized by XRD, FT-IR, low-temperature N2 adsorption-desorption measurement and solid state UV-visible diffuse reflectance spectroscopy. The photocatalytic activities of all TiO2 samples were compared using the degradation of phenol as a probe reaction. [ABSTRACT FROM AUTHOR]

The dual-energy CT-based (DECT) approach holds promise in reducing the overall uncertainty in proton stopping-power-ratio (SPR) estimation as compared to the conventional stoichiometric calibration approach. The objective of this study was to analyze the factors contributing to uncertainty in SPR estimation using the DECT-based approach and to derive a comprehensive estimate of the range uncertainty associated with SPR estimation in treatment planning. Two state-of-the-art DECT-based methods were selected and implemented on a Siemens SOMATOM Force DECT scanner. The uncertainties were first divided into five independent categories. The uncertainty associated with each category was estimated for lung, soft and bone tissues separately. A single composite uncertainty estimate was eventually determined for three tumor sites (lung, prostate and head-and-neck) by weighting the relative proportion of each tissue group for that specific site. The uncertainties associated with the two selected DECT methods were found to be similar, therefore the following results applied to both methods. The overall uncertainty (1σ) in SPR estimation with the DECT-based approach was estimated to be 3.8%, 1.2% and 2.0% for lung, soft and bone tissues, respectively. The dominant factor contributing to uncertainty in the DECT approach was the imaging uncertainties, followed by the DECT modeling uncertainties. Our study showed that the DECT approach can reduce the overall range uncertainty to approximately 2.2% (2σ) in clinical scenarios, in contrast to the previously reported 1%. [ABSTRACT FROM AUTHOR]

The paper discusses edge stability, beta limits and power handling issues for negative triangularity tokamaks. The edge magnetohydrodynamic stability is the most crucial item for power handling. For the case of negative triangularity the edge stability picture is quite different from that for conventional positive triangularity tokamaks: the second stability access is closed for localized Mercier/ballooning modes due to the absence of a magnetic well, and nearly internal kink modes set the pedestal height limit to be weakly sensitive to diamagnetic stabilization just above the margin of the localized mode Mercier criterion violation. While a negative triangularity tokamak is thought to have a low beta limit with its magnetic hill property, it is found that plasmas with reactor-relevant values of normalized beta βN > 3 can be stable to global kink modes without wall stabilization with appropriate core pressure profile optimization against localized mode stability, and also with increased magnetic shear in the outer half-radius. The beta limit is set by the n = 1 mode for the resulting flat pressure profile. The wall stabilization is very inefficient due to strong coupling between external and internal modes. The n > 1 modes are increasingly internal when approaching the localized mode limit, and set a lower beta in the case of the peaked pressure profile leading to a Mercier unstable core. With the theoretical predictions supported by experiments, a negative triangularity tokamak would become a prospective fusion energy system with other advantages including a larger separatrix wetted area, more flexible divertor configuration design, wider trapped particle-free scrape-off layer, lower background magnetic field for internal poloidal field coils, and larger pumping conductance from the divertor room. [ABSTRACT FROM AUTHOR]