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Topographic variables derived from digital elevation models (DEM) are the most commonly used predictor in soil organic carbon (SOC) prediction. The predictability of these variates for the spatial heterogenity of SOC is influenced by the size of DEM resolution. This paper aimed to investigate the resolution effect of the topography at multiple DEM resolutions and select the most important predictors and the optimal resolution for SOC prediction in a large-scale and morphologically complex area. The study area, covering 15 600 km2, was located in a mountainous province in China. A total of 3901 soil samples and three machine learning algorithms including random forest, gradient boosted regression tree, and artificial neural network were used to construct the SOC predictive models at resolutions of 30, 90, 150, 210, 270, 330, and 390 m. Topographic factors were derived from the DEM with an original resolution of 30 m and were subsequently resampled to varying resolutions by using the bilinear interpolation algorithm. The importance of each variate in each predictive model was computed for the most important predictor selection, and the determination coefficient (R2) and Root Mean Square Error (RMSE) of each predictive model were computed for the accuracy evaluation. Comparative analysis on point-based topographic representation, the accuracy of predictive models, and the variable importance was conducted among different resolutions to investigate the resolution effect on the SOC prediction and to select the optimal resolution for this study area. The results showed that topography was the key factor influencing the SOC distribution in this large-scale area due to the region's mountainous nature, and the relative contribution of the topography to predict SOC distribution varied with DEM resolutions. Elevation was the most important topographic factor at all DEM resolutions. Accuracies of predictive models built on the three machine learning algorithms were all dependent on DEM resolution, indicating that DEM resolution had an important effect on SOC prediction. Overall, the random forest predictive models outperformed the other two algorithms, and its most accurate result was obtained at the 210-m resolution with an R2 of 0.25 and an RMSE of 4.77 g kg–1. In conclusion, we found that finer resolutions did not necessarily produce more accurate SOC predictions even in a large-scale and morphologically complex area. Therefore, investigating the resolution effect is suggested to select an optimal resolution for the SOC prediction in other regions characterized by similar geomorphological conditions as this study area. [ABSTRACT FROM AUTHOR]

All living organisms require thiamine, a water-soluble vitamin, which is also reported to play a role in response to various abiotic stresses. However, the impact of thiamine on the growth of Wickerhamomyces anomalus under ethanol stress is still not completely understood. In this study, we investigated the effects of exogenous thiamine application on the growth of W. anomalus under ethanol stress. We also investigated how thiamine affected the differentially expressed metabolites (DEMs) using a non-targeted metabolomics approach. The results showed that exogenous thiamine application improved the growth of ethanol-stressed W. anomalus. The DEMs affected by exogenous thiamine application were significantly enriched as ABC transporters process, glycerophospholipid metabolism, purine metabolism, and one carbon pool via folate and sulfur relay system using Kyoto Encyclopedia of Genes and Genomics (KEGG) enrichment analysis. Several pathways, such as arginine biosynthesis, cell cycle, oxidative phosphorylation, etc., were also regulated by thiamine because they were not enriched after exogenous thiamine application. Therefore, thiamine helped to protect W. anomalus from the effects of ethanol stress. These findings offer a theoretical basis for further understanding the regulatory mechanism of thiamine-mediated ethanol stress tolerance in W. anomalus. [ABSTRACT FROM AUTHOR]

The significance of the Gallium Anomaly, from the BEST, GALLEX, and SAGE radioactive source experiments, is quantified using different theoretical calculations of the neutrino detection cross section, and its explanation due to neutrino oscillations is compared with the bounds from the analyses of reactor rate and spectral ratio data, β-decay data, and solar neutrino data. In the 3+1 active-sterile neutrino mixing scheme, the Gallium Anomaly is in strong tension with the individual and combined bounds of these data sets. In the combined scenario with all available data, the parameter goodness of fit is below 0.042%, corresponding to a severe tension of 4–5σ, or stronger. Therefore, we conclude that one should pursue other possible solutions beyond short-baseline oscillations for the Gallium Anomaly. We also present a new global fit of νe and ν ¯ e disappearance data, showing that there is a 2.6–3.3σ preference in favor of short-baseline oscillations, which is driven by an updated analysis of reactor spectral ratio data. [ABSTRACT FROM AUTHOR]

Coherent elastic neutrino-nucleus scattering (CEνNS) represents a powerful tool to investigate key electroweak physics parameters and neutrino properties since its first observation in 2017 by the COHERENT experiment exploiting the spallation neutron source at Oak Ridge National Laboratory. In light of the recent detection of such a process with antineutrinos produced by the Dresden-II reactor scattering off a germanium detector, we revisit the limits so far set on the neutrino magnetic moments, charge radii and millicharges as well as on the weak mixing angle. In order to do so, we also include the contribution of elastic neutrino-electron scattering, whose effect becomes non negligible in some beyond the Standard Model theories. By using different hypotheses for the germanium quenching factor and the reactor antineutrino flux, we provide a measurement of the weak mixing angle at the low-energy scale of the Dresden-II reactor experiment and, thanks to a combined analysis with the latest cesium iodide and argon data set released by the COHERENT Collaboration, we deliver updated limits for the neutrino electromagnetic properties. Interestingly, we are able to set a new best upper limit on the electron neutrino charge radius and significantly improve the other CEνNS-related limits on the neutrino electric charge and magnetic moment. [ABSTRACT FROM AUTHOR]

We present the constraints on the parameters of several light boson mediator models obtained from the analysis of the current data of the COHERENT CEνNS experiment. We consider a variety of vector boson mediator models: the so-called universal, the B − L and other anomaly-free U(1)′ gauge models with direct couplings of the new vector boson with neutrinos and quarks, and the anomaly-free Le− Lμ, Le− Lτ, and Lμ− Lτ gauge models where the coupling of the new vector boson with the quarks is generated by kinetic mixing with the photon at the one-loop level. We consider also a model with a new light scalar boson mediator that is assumed, for simplicity, to have universal coupling with quarks and leptons. Since the COHERENT CEνNS data are well-fitted with the cross section predicted by the Standard Model, the analysis of the data yields constraints for the mass and coupling of the new boson mediator that depend on the charges of quarks and neutrinos in each model under consideration. We compare these constraints with the limits obtained in other experiments and with the values that can explain the muon g − 2 anomaly in the models where the muon couples to the new boson mediator. [ABSTRACT FROM AUTHOR]

We present new constraints on three different models, the so-called universal, B − L and Lμ− Lτ models, involving a yet to be observed light vector Z′ mediator, by exploiting the recent observation of coherent elastic neutrino-nucleus scattering (CEνNS) in argon and cesium-iodide performed by the COHERENT Collaboration. We compare the results obtained from a combination of the above data sets with the limits derived from searches in fixed target, accelerator, solar neutrino and reactor CEνNS experiments, and with the parameter region that could explain the anomalous magnetic moment of the muon. We show that for the universal and the B − L models, the COHERENT data allow us to put stringent limits in the light vector mediator mass, MZ′, and coupling, gZ′, parameter space. [ABSTRACT FROM AUTHOR]

The method of constructing a 2D simulation model based on the real microstructure is developed to simulate the microstructural evolution of materials. Microstructure photographs of two typical metallic materials, 40Cr and TC4, are analyzed by scanning electron microscopy-electron backscattering diffraction. Then, the photographs are converted into digital images and the grain topology information in the photographs is reserved. Based on this information, the true microstructure of materials is rebuilt with the finite element software ABAQUS using the PYTHON rogramming language. The 2D model the true microstructure will be of importance for improving the accuracy of elastoplastic finite element simulation for polycrystals. [ABSTRACT FROM AUTHOR]

Two-dimensional transition metal dichalcogenide materials, such as the heterobilayers by piling up the monolayers in out-of-plane direction, behave unique performances in applications of nanoelectronic components. In this work, the in-plane thermal conductivities of MoS2–MoSe2, MoS2–WS2, and MoS2–WSe2 heterobilayers are investigated with nonequilibrium molecular dynamics method by considering the effects of system dimensions, temperature, coupling strength, strain, and misorientation. The results show that the thermal conductivity decreases as the temperature rises from 100 K to 500 K. The effect of coupling strength on the thermal conductivity is not significant. Both strain and misorientation could result in a reduction in the thermal conductivity, and the effect of tensile strain is stronger than that of compressive strain. An analysis based on phonon spectral energy density is performed to further understand phonon thermal properties in heterobilayers. This work provides a fundamental basis for regulating thermal transport in two-dimensional heterobilayer-based nanoelectronics. [ABSTRACT FROM AUTHOR]

Interfacial stress transfer of single-walled carbon nanotube-reinforced polymer composites subjected to uniaxial tension was investigated by a newly developed shear-lag model integrated with a spring layer model. A linear relationship between the tangential relative displacement and the interfacial shear stress was assumed for the interface which is determined by van der Waals forces. The interface stiffness parameter was determined through comparing the stress distribution of the shear-lag model with multiscale simulation results. The effect of the interface stiffness and the nanotube's aspect ratios on the distribution of stress in CNT-reinforced composites was studied. [ABSTRACT FROM AUTHOR]

As an indispensable stage of product manufacturing, assembly process plays an important role in assuring product reliability by curbing the variation of assembly quality characters. The characters, mainly affected by the uncertainty components quality and assembly process parameters, are formed in a complex process. This paper approaches the uncertainty analysis of the assembly quality characters and the determination of key quality influence factors under multi-source uncertainty. Firstly, the fuzzy theory-based analytic hierarchy process(FAHP) is carried out to identify the main factors and the information entropy method is used to transfer them into uniform uncertainty variables. Secondly, the support vector regression (SVR) method is used to establish the surrogate model between the influence factors and assembly quality characters. Monte Carlo simulation (MCS) is employed for uncertainty analysis and sensitivity analysis of assembly process on the basis of the surrogate model and data sampling, which realize the prediction of assembly quality and the determination of key process parameters. Finally, a case study of a bolt assembly process is used to verify the effectiveness of the proposed method. The proposed method in this paper is efficient and simple to apply in manufacturing applications directly. [ABSTRACT FROM AUTHOR]

The La0.67Ca0.20Sr0.13MnO3 nanoparticles and bulks were prepared by using sol-gel method (SGM) and spark plasma sintering (SPS), respectively. The X-ray diffraction analysis indicates each sample crystal in a single rhombohedral perovskite structure (space group R 3 ¯ c ). The Curie temperature is slightly improved and the phase transition is sharpened after processing with SPS. The enhancement of magnetocaloric effect (MCE) is also observed in the samples prepared by SPS. For a field change of 3 T, the maximum isothermal entropy change is improved by 32 and 117% when different sintering temperatures and sintering pressures are applied. The magnetic phase transition and MCE can be well described by the Landau theory. The present studies suggest that the perovskite bulks prepared by SPS could be useful for the application of magnetic refrigeration. [ABSTRACT FROM AUTHOR]

A new cobalt(II) coordination polymer, namely [Co(L)(Ndc)]n (I), where L = 1,5-bis(5,6- dimethylbenzimidazole)pentane, H2Ndc = 2,6-naphthalenedicarboxylic acid, was synthesized and characterized by elemental analysis, IR spectra, powder X-ray diffraction and single-crystal X-ray diffraction (CIF file CCDC no. 1548044). Complex I displays a 2D (4,4) layer which further extended into a 3D supramolecular framework via weak C-H···O hydrogen bondings. The luminescence explorations demonstrated that I exhibits highly selective and sensitive sensing for Cr2O72− with high quenching efficiency Ksv value of 9.87 × 103 L mol−1 and low detection limit (0.24 μM (S/N = 3)). Meanwhile I also exhibits highly selective and sensitive sensing for Fe3+ with quenching efficiency Ksv = 3.6 × 104 L mol-1 and low detection limit (0.32 μM (S/N = 3)). Complex I exhibits higher photocatalytic activities for the degradation of methylene blue under UV irradiation. Additionally, the thermal behavior and electrochemical properties of the compound are also presented. [ABSTRACT FROM AUTHOR]

Shape instability belongs to one of significant types of violation for disposable structural elements under high-stress levels. Due to lack of fundamental data on materials, it is quite problematic to consider the shape instability in the design of disposable structural elements. The crystal plastic finite element method is proposed to investigate the dispersion of shape instability life data. It allows these data to be obtained from traditional material parameters. The shape instability behavior is described with the constitutive crystal model of plastic damage accumulation. Then, to improve the accuracy of life prediction, the new method is developed to construct the simulation model of true microstructure. A modeling algorithm based on the image processing technology is provided to reduce the virtual stresses from the transient crystal plastic modeling method. Comparison of experimental and predicted results shows good agreement at high stresses close to the elastic limit of the material. [ABSTRACT FROM AUTHOR]

Day-night asymmetries in active-sterile solar neutrino oscillations are discussed in the general 3 + Ns mixing framework with three active and Ns sterile neutrinos. Analytical expressions of the probability of neutrino flavor transitions in the Earth in the perturbative approximation and in the slab approximation are presented and the effects of active-sterile mixing and of the CP-violating phases are discussed. The accuracy of the analytical approximations and the properties of the day-night asymmetries are illustrated numerically in the 3+1 neutrino mixing framework. [ABSTRACT FROM AUTHOR]

Undoped n-type MgZnO films were deposited on c-plane sapphire substrates by molecular-beam epitaxy and subsequently annealed in O at different pressures. After annealing at 3.03 × 10 Pa, oxygen content in the annealed films show increases and the films transform into p-type conduction. However, the decreases of oxygen content and the increases of electron concentration were obtained while the films annealed at 1.01 × 10 Pa or 2.05 × 10 Pa. The changes in intensity of the emission peak located at 2.270 eV are similar to the changes of the oxygen content in the films annealed at different pressures. According to the defect levels and the relationship between photoluminescence spectra and annealing condition, it was suggested that this emission peak was related to interstitial oxygen (O). The obtained p-type conduction is attributed to that the O acceptor can compensate oxygen vacancy and interstitial zinc donor. [ABSTRACT FROM AUTHOR]

Summary: Systemic treatment with strontium ranelate (SR) was performed on ovariectomized (OVX) rats with fractured tibiae. Callus quality was assessed by radiographic, histological, micro-computerized tomography, and biomechanical examinations at 4 and 8 weeks after fracture. Results revealed that systemic applied SR promoted osteoporotic fracture healing. Introduction: Several studies have demonstrated the dual effect of SR on osteoporotic and undisturbed bone. However, reports of their effect on osteoporotic fracture healing are limited. This study was designed to investigate the effects of SR on bone regeneration in OVX rats with fractured tibiae. Methods: Three months after being OVX, female Sprague-Dawley rats accepted bilateral osteotomy on proximal tibiae fixed with intramedullary wires and were divided into two groups: OVX and OVX + SR (625 mg/kg/day). Callus quality was evaluated at 4 and 8 weeks postfracture. Results: Compared with OVX group, SR treatment significantly increased bone formation, BMD, biomechanical strength, and improved microstructural properties of the callus. The ultimate load was increased by 211.0% and 61.4% ( p < 0.01), and the total bone volume of callus by 74.8% and 79.3% ( p < 0.01) at 4 and 8 weeks postfracture, respectively. SR treatment also promoted healing progress with increased osteogenesis at 4 weeks; more mature and tightly arranged woven or lamellar bone at 8 weeks across the fracture gap in histological analysis. Conclusion: This study suggests that systemic treatment with strontium ranelate could promote tibial fracture healing in OVX rats. [ABSTRACT FROM AUTHOR]

Gene transfer of the Escherichia coli purine nucleoside phosphorylase (PNP) results in potent cytotoxicity after administration of the prodrug fludarabine phosphate (F-araAMP). Here, we have tested whether application of this strategy in the context of replication-competent retrovirus (RCR) vectors, which can achieve highly efficient tumor-restricted transduction as well as persistent expression of transgenes, would result in effective tumor inhibition, or, alternatively, would adversely affect viral replication. We found that RCR vectors could achieve high levels of PNP expression concomitant with the efficiency of their replicative spread, with significant cell killing activity in vitro and potent therapeutic effects in vivo. In U-87 xenograft models, replicative spread of the vector resulted in progressive transmission of the PNP transgene, as evidenced by increasing PNP enzyme activity with time after vector inoculation. On F-araAMP administration, high efficiency gene transfer of PNP by the RCR vector resulted in significant suppression of tumor growth and extended survival time. As the RCR mediates stable integration of the PNP gene and continuous expression, an additional round of F-araAMP administration resulted in further survival benefit. RCR-mediated PNP suicide gene therapy thus represents a highly efficient form of intracellular chemotherapy, and may achieve effective antitumor activity with less systemic toxicity. [ABSTRACT FROM AUTHOR]

The dominant part of PBDEs residue in pig tissues was BDE-47 accounted for 48.2% ~ 66.9%, followed by BDE-99 from 15.9% to 24.2%. When the data were on lipid weight basis, the ∑PBDEs concentrations in tissues of individual pig showed the same order of liver > muscle, intestine > fat. Principal component analysis and PBDE congener mean concentration ratios of muscle versus liver (M/L), fat versus liver (F/L) and intestine versus liver (I/L) showed the higher accumulation ability of PBDEs in liver than in other tissues. And the PBDE mean concentration ratios of M/L, F/L and I/L had the trend of decrease with increasing bromination degree of PBDE congeners. [ABSTRACT FROM AUTHOR]

37 PBDE congeners were analyzed at six different depths in two soil cores taken from a typical electronic waste polluted area in South China. The PBDEs were congregated in the surface layer (0–5 cm) of soil cores and were 29 times in MK and 18 times in NW higher than the second lower layers (5–10 cm). As a whole, the concentrations of PBDEs were decreased with the soil depth increased in two cores. Lower brominated PBDE had higher penetrability than the deca-BDE in soil. The deca-BDE could be detected in deeper soil layers (15–20 cm in MK and 20–30 cm in NW) and the percentage of deca-BDE decreased with the increase of depth. [ABSTRACT FROM AUTHOR]

Acute kidney injury (AKI) is a common early complication in patients with hematopoietic SCT (HSCT). However, there are limited data about the incidence and risk factors of AKI in patients with nonmyeloablative HSCT. We conducted a multicenter, retrospective cohort study of 62 patients from three institutions who were treated with similar protocols for nonmyeloablative HSCT. AKI was classified according to the Acute Kidney Injury Network criteria. It was shown that 29% of the patients developed AKI in the first 100 days after nonmyeloablative HSCT. The risk factor at baseline for AKI was incomplete HLA-matched transplant (odds ratio (OR) 3.6; 95% confidence interval (CI) 1.1–13.0). Complications such as acute GVHD, veno-occlusive disease of liver and sepsis were also associated with the development of AKI (OR 12.1; 95% CI 2.4–62.4). AKI was significantly associated with mortality (OR=4.7; 95% CI 1.9–11.5). We concluded that AKI is a very common complication in patients with nonmyeloablative HSCT, which is associated with incomplete HLA-matched transplant and complications, and has an important impact on the patients’ first year of survival. [ABSTRACT FROM AUTHOR]

We use state-of-the-arts first-principles method to investigate the structural, electronic, and magnetic properties of stoichiometric LiFeAs. We optimize fully all the structures, including lattice constants and internal position parameters, for different magnetic orders. We find the magnetic ground state by comparing the total energies among all the possible magnetic orders. Our calculated lattice constants and As internal position are in good agreement with experiment. The experimental fact that no magnetic phase transition has been observed at finite temperature can be attributed to the tiny inter-layer spin coupling. Our results show that stoichiometric LiFeAs has almost the same striped antiferromagnetic spin order as other FeAs-based parent compounds and tetragonal FeSe do, which may imply that all Fe-based superconductors have the same mechanism of superconductivity. [ABSTRACT FROM AUTHOR]

Passivation of the electronic defect states at a SiNx/InGaAs interface has been achieved using (NH4)2Sx treatments of the InGaAs surface. The X-ray photoelectron spectroscopy technique was used to investigate the mechanism of sulfur passivation. The results indicate that sulfur treatment can effectively erase the native oxides, and S-In, S-Ga and S-As bondings are formed after sulfidation. The fabrication of Au/SiNx/InGaAs metal–insulator–semiconductor diodes has been achieved by depositing a layer of SiNx on (NH4)2Sx-treated n-InGaAs using the plasma enhanced chemical vapor deposition technique. The effect of passivation on the InGaAs surface before and after annealing was evaluated by current–voltage and capacitance–voltage measurements. The results indicate that the SiNx passivation layer exhibits good insulative properties. The annealing contributes to the decrease of the fixed charge density and the minimum surface state density, which are 4.5×1011 cm-2 and 3.92×1011 cm-2 eV-1, respectively. A 256×1 InP/InGaAs/InP heterojunction short-wavelength infrared detector, fabricated with the sulfidation plus a SiNx passivation layer, has shown a good response uniformity of 4.81%. [ABSTRACT FROM AUTHOR]

To evaluate whether parvovirus B19, a common human pathogen, was also involved in papillary thyroid carcinoma (PTC), 112 paraffin-embedded thyroid specimens of benign nodules, papillary, medullary and follicular carcinomas, and normal controls were examined for B19 DNA and capsid protein by nested PCR, in situ hybridisation (ISH) and immunohistochemistry (IHC). The expression of the nuclear factor-kappaB (NF-kappaB) was investigated by IHC. The results showed B19 DNA commonly exists in human thyroid tissues; however, there were significant differences between PTC group and normal controls, and between PTC and nonneoplastic adjacent tissues (P<0.001). The presence of viral DNA in PTC neoplastic epithelium was confirmed by laser-capture microdissection and sequencing of nested PCR products. B19 capsid protein in PTC group was significantly higher than that of all the control groups and nonneoplastic adjacent tissues (P

The photo-thermo-sensitive male sterile (PTMS) wheat line BS20 showed male sterility under short-day photoperiod and low temperature conditions. Photo-thermo-controlled growth chambers were used to study the fertility alteration characteristics of PTMS wheat line BS20. The period of photo-sensitivity and thermo-sensitivity was coincident with the pollen development stages from pollen mother cell (PMC) formation to mono-nucleate. Fertility alteration of BS20 was induced mainly by temperature, and the critical point of temperature was 10–12∘C. Below the critical temperature, BS20 remained sterile and was not affected by photoperiod. However, above the critical temperature, the fertility of BS20 improved as the temperature rose. In the temperature range of 12–14∘C the fertility of BS20 improved significantly as the photoperiod extended. [ABSTRACT FROM AUTHOR]

A method for fluorimetric microscopic determination of trace amounts of fluorescein at the femtomole level has been developed. Since the solvent evaporates from the droplet on a hydrophobic-treated glass slide, an outward capillary flow of the solvent from the interior of the droplet occurs. The resulting outward capillary flow then carries the solute to the perimeter of the droplet spot, where the solute accumulates to form a fluorescent self-ordered ring (SOR). Depending on the volume of the droplet of fluorescein solution, SORs of different sizes with an outer diameter less than 1.2 mm and a ring belt width less than 24 μm can be obtained. Data analysis for a digitally imaged SOR using a charge-coupled device (CCD) camera showed that the fluorescein molecules across the fluorescent SOR belt section follow a Gaussian distribution; the maximum fluorescent intensity at central ring belt ( I max) was found to be proportional to fluorescein content. When a 0.1-μL droplet was spotted on the solid support, fluorescein in a range of 0.6–120 femtomol (or 6.2–1200.0 nM) can be detected, and the limit of detection can reach 62 attomol (or 0.6 nM). With the present method, the contents of fluorescein in fluorescein sodium injections were satisfactorily detected with recoveries of 95–105% and RSD of 3.5 and 4.2%, respectively. [ABSTRACT FROM AUTHOR]

Telluride-bearing gold deposits of the Pingyi area, western Shandong, China, are located on the southeastern margin of the North China Craton. There are two main types of deposits: (i) mineralized cryptoexplosive breccia, e.g., Guilaizhuang; and (ii) stratified, finely-disseminated mineralization hosted in carbonate rocks, e.g., Lifanggou and Mofanggou deposits. In Guilaizhuang, the cryptoexplosive breccia is formed within rocks of the Tongshi complex and Ordovician dolomite. The mineralization is controlled by an E–W-trending listric fault. Stratified orebodies of the Lifanggou and Mofanggou deposits are placed along a NE-trending, secondary detachment zone. They are hosted within dolomitic limestone, micrite and dolomite of the Early-Middle Cambrian Changqing Group. The mineralization in the ore districts is considered to be related to the Early Jurassic Tongshi magmatic complex that formed in a continental arc setting on the margin of the North China Craton. The host rocks are porphyritic and consist predominantly of medium- to fine-grained diorite and pyroxene (hornblende)-bearing monzonite. SHRIMP U–Pb zircon dating of diorites give a 206Pb/238U weighted mean age of 175.7 ± 3.8 Ma. This is interpreted as representing the crystallization age of the Tongshi magmatic complex. Considering the contact relationships between the magmatic and host sedimentary rocks, as well as the genetic link with the deposits, we conclude that this age is relevant also for the formation of mineralization in the Pingyi area. We hence consider that the deposits formed in the Jurassic. The principal gold minerals are native gold, electrum and calaverite. Wall-rock alteration comprises pyritization, fluoritization, silicification, carbonatization and chloritization. Fluid inclusion studies indicate that all the analyzed inclusions are of two-phase vapor–liquid NaCl–H2O type. Homogenization temperatures of the fluid inclusions vary from 103 °C to 250 °C, and the ice melting temperatures range from −2.5 °C to −13.5 °C, corresponding to a salinity range of 4.65 to 17.26 wt.% NaCl equiv. The δ34S values of pyrite associated with gold mineralization exhibit a narrow range of −0.71 to + 2.99‰, implying that the sulfur was probably derived from the mantle and/or dioritic magma. The δ13CPDB values of the fluid inclusions in calcite range from −7.3 to 0.0‰. The δ18OSMOW values of vein quartz and calcite range from 11.5 to 21.5‰, corresponding to δ18Ofluid values of −1.1 to 10.9‰; δD values of the fluid inclusions vary between −70 and −48‰. The isotope data for all three deposits suggest mixing of ore-forming fluids derived from the mantle and/or magma with different types of fluids at shallow levels. Pressure release and boiling of the fluids, as well as fluid-rock interaction (Lifanggou and Mofanggou) and mixing of magmatically-derived fluids with meteoritic waters (Guilaizhuang) played an important role in the ore-forming processes. [ABSTRACT FROM AUTHOR]

Because of the large size of the former Soviet Union (FSU) and the heavy use of organochlorine pesticides (OCPs) in the FSU, usage information regarding OCPs in the FSU is important in compiling global emission inventories and thus in studying the transport of OCPs among different environmental compartments worldwide. The availability of such information is limited. By analyzing the available 1,2,3,4,5,6-hexachlorocyclohexane (HCH) data in the FSU, this article presents estimates of HCH usage in this region from 1950 to 1990, when HCH was officially banned for agricultural use by the FSU government. The creation of HCH usage inventories for the FSU has paved the way to produce HCH emission inventories for this region. Total HCH usages for agricultural purposes in the FSU from 1950 to 1990 were estimated to be 1,960 kt for technical HCH and 40 kt for lindane. The total usage for the isomers was 270 kt for ?-HCH, 1,270 kt for a-HCH, and 170 kt for ß-HCH. Use of HCH reached a peak in 1965: 130 kt for technical HCH, 2.7 kt for lindane, 18 kt for ?-HCH, 86 kt for a-HCH, and 11 kt for ß-HCH. Gridded usage data sets in the FSU of technical HCH and lindane-and the a-HCH, ß-HCH and ?-HCH isomers-on a 1o × 1o longitude and latitude grid system for 1980 are freely available to all users at. [ABSTRACT FROM AUTHOR]

China banned the use of technical HCH (BHC: 1,2,3,4,5,6-hexachlorocyclohexane) in 1983; lindane has been used in this country since 1991. The total production was around 4 million t for technical HCH from 1952 to 1984, and 11,400 t for lindane between 1991 and 2000. Though the total produced technical HCH was considered to be used in China, only 3,200 t of lindane were used between 1991 and 2000 with the rest for export or on unused stack. Annual usage of these two compounds was located into each province first and then broken for different crops. Inventories of gridded usage of both technical HCH and lindane with 1/6° by 1/4° latitude/longitude resolution have been created by different gridded cropland data sets as surrogate data. The intensive use of technical HCH on croplands was concentrated in the southeastern part of China, but the use of lindane was concentrated in the northern part of China. [ABSTRACT FROM AUTHOR]

In this article, lead (Pb) content in snow of the early 1990s' from the Arctic, Antarctica and the Tibetan Plateau will be discussed, based on measurements along 1990 International Trans-Antarctic Expedition route, three glaciers on Tibetan Plateau as well as snowpack over the Canadian and central Arctic. Author C.D. Xiao and colleagues seek to highlight the human influence on atmosphere over the most remote regions and the upper troposphere. The distribution of Pb over northern Canada indicates that the Northwest Territory (NWT) of Canada is not an efficient channel for Pb transport to central Arctic. Pb concentrations display a decreasing trend from Ely to NWT Canada.