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Sedimentary carbonates are known to be carried into the deep mantle by subducted slabs, and studies on mantle‐derived magmas have attempted to trace the recycled carbonate in their mantle source. However, the final depth of storage of recycled carbonate and the role of recycled carbonate in the partial melting of mantle remain controversial. Peralkaline‐carbonatite suites are considered to have been derived from a carbonated mantle source and are windows to evaluate carbon in the mantle. In this study, we report the Zn isotopic compositions of a peralkaline‐carbonatite suite from the Tarim Large Igneous Province (Tarim LIP). The peralkaline‐carbonatite suite has heavier δ66Zn than normal mantle with δ66Zn of 0.34–0.40 ‰ for nephelinite, 0.35–0.47 ‰ for aillikite, 0.51–0.55 ‰ for nepheline syenite, 0.58–0.67 ‰ for calciocarbonatite and 0.38–0.56 ‰ for magnesiocarbonatite. The heavy Zn isotopic compositions of the peralkaline‐carbonatite suite in the Wajilitag complex suggest the incorporation of recycled carbonate‐bearing materials into the deep mantle. We infer that the calciocarbonatite was produced by the initial partial melting of subducted MgSiO3/MgO + C‐bearing carbonated eclogite, whereas the magnesiocarbonatite, aillikite, and nephelinite are considered as reacted melts between carbonated eclogite‐derived melts and peridotite. The heavy Zn isotopic compositions of the nepheline syenite are attributed to fractional crystallization from nephelinite magma in the magma reservoir. Our study highlights the incorporation of carbonated eclogite as an important agent of recycled carbon in the deep mantle and interactions between carbonated eclogite‐derived melts and peridotite lead to the complex lithological heterogeneities in the peralkaline‐carbonatite suite in Tarim LIP. Key Points: Zn isotopes of the peralkaline‐carbonatite suite in TLIP show that the subducted carbon is recycled in the form of MgSiO3/MgO + CThe carbonated eclogite‐derived melt‐peridotite reaction as the key for the formation of aillikite and nephelinite in TLIPThe incorporation of carbonated eclogite as an important source of recycled carbon in the deep mantle [ABSTRACT FROM AUTHOR]

The origin of lamprophyres associated with large igneous provinces (LIPs) remains controversial, particularly whether they are derived by direct melting of mantle plumes, or from previously metasomatized domains in thermally perturbed subcontinental lithosphere. Here, we report the petrological and geochemical characteristics of a recently identified suite of alkaline lamprophyres (sannaites) that represent the final pulse of magmatism in the Permian Tarim LIP in NW China. The sannaites display porphyritic texture with phenocrysts of olivine, clinopyroxene, hornblende, phlogopite, and titanomagnetite in a groundmass of plagioclase, clinopyroxene, nepheline, hornblende, biotite, and titanomagnetite with minor pyrite and apatite. Carbonate ocelli and almost pure albite in the groundmass are interpreted to have crystallized from immiscible carbonate and hydrous fluids, respectively, produced by late-stage magmatic segregation. The rocks show low to moderate SiO2 (37.7–49.3 wt.%) and MgO (2.74–9.91 wt.%), together with high Fe2O3T (up to 22.7 wt.%) and alkali contents (up to 9.02 wt.% Na2O + K2O). They are characterized by high incompatible element abundances, especially a marked enrichment in large-ion lithophile elements (Rb and Ba) and light rare-earth elements (e.g. La and Ce) relative to P and high-field-strength elements (e.g. Ti). They show a relatively restricted range of δ66Zn values between 0.22‰ and 0.46‰ with an average of 0.37 ± 0.04‰ (2SE, n  = 10), which is marginally heavier than that of MORBs (0.27 ± 0.05‰). Their (87Sr/86Sr)t values range from 0.7035 to 0.7061, εNd(t) from −0.97 to +5.62, and δ26Mg from −0.36‰ to −0.17‰ (n  = 8), the latter being consistent with those of global MORBs. Based on the correlation between Zn isotopes and TiO2–FeO concentrations, we infer that the heavy Zn isotopes in some of the sannaites resulted from fractional crystallization of Fe–Ti oxide minerals. The whole rock geochemical features of these rocks (negative K anomalies and enrichment in large-ion lithophile elements) and rhyolite–MELTS simulations suggest that the primary magmas of the sannaites were derived from an amphibole-bearing enriched lithospheric mantle source. Metasomatism and related formation of amphibole-bearing metasomatized mantle may be linked to sublithospheric melts/fluids derived from the Tarim plume in the earlier stages of plume activity, rather than slab-derived fluids or carbonate melts as suggested in previous studies for other alkaline mantle-derived magmas. Partial melting may have been triggered by the thermal input from the Tarim plume during a later stage. This study suggests that exotic, alkali-rich magmas can be produced during the multi-stage evolution of large mantle plumes, involving complex cycles of lithospheric mantle metasomatism and later melting of previously enriched domains. [ABSTRACT FROM AUTHOR]

To identify the key indicators for salt tolerance evaluation of Salix matsudana Koidz, we explored the relationship of ion absorption and distribution with chlorophyll, fluorescence parameters (leaf performance index, maximum photochemical efficiency), and photosynthetic gas parameters (net photosynthetic rate, transpiration, stomatal conductance, intercellular carbon dioxide concentration) under salt stress. We established 4 treatment groups and one control group based on salinity levels of NaCl hydroponic solutions (171, 342, 513, and 684 mm). The Na+/K+, Na+/Ca2+, chlorophyll fluorescence, and photosynthetic parameters of leaves were measured on the 1st, 3rd, 5th, 8th, 11th, and 15th days to analyze the correlations of chlorophyll, chlorophyll fluorescence and photosynthetic parameters to the ion distribution ratio. The results showed that (1) The ratio of the dry weight of roots to leaves gradually increased with increasing salt concentration, whereas the water content of leaves and roots first increased and then decreased with increasing time. (2) The content of Na+, Na+/K+, and Na+/Ca2+ in roots and leaves increased with increasing salt stress concentration and treatment time, and the difference gradually narrowed. (3) Ca2+ was lost more than K+ under salt stress, and Na+/Ca2+ was more sensitive to the salt stress environment than Na+/K+. (4) Because the root system had a retention effect, both Na+/K+ and Na+/Ca2+ in roots under different NaCl concentrations and different treatment times were higher than those in leaves, and Na+/Ca2+ was much higher than Na+/K+ in roots. (5) Na+/K+ had a higher correlation with fluorescence parameters than Na+/Ca2+. Among them, Na+/K+ had a significantly negative correlation with the maximum photochemical efficiency, and the correlation coefficient R 2 was 0.8576. (6) Photosynthetic gas parameters had a higher correlation with Na+/Ca2+ than with Na+/K+. Among them, significantly negative correlations were noted between Na+/Ca2+ and Gs as well as between Na+/Ca2+ and E under salt stress. The correlation between Na+/Ca2+ and Gs was the highest with a correlation coefficient of 0.9368. (7) Na+/K+ and Na+/Ca2+ had no significant correlation with chlorophylls. Na+/Ca2+ was selected as a key index to evaluate the salt tolerance of S. matsudana Koidz, and the results provided a reference for analyzing the relationship between ion transport and distribution for photosynthesis. [ABSTRACT FROM AUTHOR]

Objective: The purpose of this study was to explore the adaptive mechanism underlying the photosynthetic characteristics and the ion absorption and distribution of white willow (Salix alba L.) in a salt stress environment in cutting seedlings. The results lay a foundation for further understanding the distribution of sodium chloride and its effect on the photosynthetic system. Method: A salt stress environment was simulated in a hydroponics system with different NaCl concentrations in one-year-old Salix alba L.branches as the test materials. Their growth, ion absorption, transport and distribution in the roots and leaves, and the changes in the photosynthetic fluorescence parameters were studied after 20 days under hydroponics. Results: The results show that The germination and elongation of roots are promoted in the presence of 171mM NaCl, but root growth is comprehensively inhibited under increasing salt stress. Under salt stress, Na+ accumulates significantly in the roots and leaves, and the Na+ content and the Na+/K+ and Na+/Ca2+ root ratios are significantly greater than those in the leaves. When the NaCl concentration is ≤ 342mM, Salix alba can maintain relatively stable K+ and Ca2+ contents in its leaves by improving the selective absorption and accumulation of K+ and Ca2+ and adjusting the transport capacity of mineral ions to aboveground parts, while K+ and Ca2+ levels are clearly decreased under high salt stress. With increasing salt concentrations, the net photosynthetic rate (Pn), transpiration rate (E) and stomatal conductance (gs) of leaves decrease gradually overall, and the intercellular CO2 concentration (Ci) first decreases and then increases. When the NaCl concentration is < 342mM, the decrease in leaf Pn is primarily restricted by the stomata. When the NaCl concentration is > 342mM, the decrease in the Pn is largely inhibited by non-stomatal factors. Due to the salt stress environment, the OJIP curve (Rapid chlorophyll fluorescence) of Salix alba turns into an OKJIP curve. When the NaCl concentration is > 171mM, the fluorescence values of points I and P decrease significantly, which is accompanied by a clear inflection point (K). The quantum yield and energy distribution ratio of the PSⅡ reaction center change significantly (φPo, Ψo and φEo show an overall downward trend while φDo is promoted). The performance index and driving force (PIABS, PICSm and DFCSm) decrease significantly when the NaCl concentration is > 171mM, indicating that salt stress causes a partial inactivation of the PSII reaction center, and the functions of the donor side and the recipient side are damaged. Conclusion: The above results indicate that Salix alba can respond to salt stress by intercepting Na+ in the roots, improving the selective absorption of K+ and Ca2+ and the transport capacity to the above ground parts of the plant, and increasing φDo, thus shows an ability to self-regulate and adapt. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzothiophenes (PCDTs) are sulfur analogues of polychlorinated dibenzofurans with prevalent occurrence in aquatic environments and potential ecological risks. However, data on the behavior and toxicity of PCDTs in aquatic organisms remain scarce. In the present study, the bioaccumulation, metabolism, and oxidative damage of 4‐mono‐chlorinated dibenzothiophene (4‐mono‐CDT) in freshwater mussel (Hyriopsis cumingii) were investigated after exposure to 4‐mono‐CDT in semistatic water. The uptake rates, depuration rates, half‐lives, and bioconcentration factors of 4‐mono‐CDT in hepatopancreas, gill, and muscle tissues ranged from 0.492 to 1.652 L d−1 g−1 dry weight, from 0.117 to 0.308 d−1, from 2.250 to 5.924 d, and from 2.903 to 8.045 × 103 L kg−1 dry weight, respectively. A dechlorinated metabolite (dibenzothiophene) was detected in hepatopancreas tissue, indicating that dechlorination was the main metabolic pathway of 4‐mono‐CDT. As the exposure time increased, the activities of superoxide dismutase, catalase, and glutathione peroxidase were induced or inhibited in the different experimental groups. The malondialdehyde content increased with increasing 4‐mono‐CDT dose and exposure time. A higher concentration of 4‐mono‐CDT corresponded to a greater integrated biomarker response in each tissue and greater oxidative damage. The antioxidant enzymes in hepatopancreas were more sensitive to 4‐mono‐CDT than those in gill. The results provide useful information on the behavior and ecotoxicity of PCDTs in freshwater mussels. Environ Toxicol Chem 2021;40:1873–1882. © 2021 SETAC [ABSTRACT FROM AUTHOR]

Aillikites are carbonate-rich ultramafic lamprophyres often associated with carbonatites. Despite their common field relationships, the petrogenetic links, if any, between aillikites and carbonatites remain controversial. To address this question, this study reports the results of a detailed geochemical and isotopic examination of the Permian Wajilitag aillikites in the northwestern Tarim large igneous province, including bulk-rock major- and trace-element and Sr–Nd isotope compositions, olivine major- and trace-element and (in situ secondary ion mass spectrometry) oxygen isotope compositions, oxygen isotope data for clinopyroxene separates, and bulk-carbonate C–O isotopic analyses. Olivine in the aillikites occurs in two textural types: (1) microcrysts, 0·3–5 mm; (2) macrocrysts, 0·5–2·5 cm. The microcrysts exhibit well-defined linear correlations between Fo (79–89) and minor and trace elements (e.g. Ni = 1304–3764 μg g–1 and Mn = 1363–3042 μg g–1). In contrast, the olivine macrocrysts show low Fo (79–81), Ni (5·3–442 μg g–1) and Ca (477–1018 μg g–1) and very high Mn (3418–5123 μg g–1) contents, and are displaced from the compositional trend of the microcrysts. The microcrysts are phenocrysts crystallized from the host aillikite magmas. Conversely, the lack of mantle-derived xenoliths in these aillikites suggests that the macrocrysts probably represent cognate crystals (i.e. antecrysts) that formed from earlier, evolved aillikite melts. Olivine phenocrysts in the more primitive aillikite dykes (Dyke 1) have relatively higher Fo (Fo82–89) and mantle-like oxygen isotope values, whereas those in the more evolved dykes (Dykes 2 and 3) exhibit lower Fo (Fo79–86) and oxygen isotope values that trend toward lower than mantle δ18O values. The decreasing δ13C values of carbonate from Dyke 1 to Dykes 2 and 3, coupled with the indistinguishable Sr–Nd isotopes of these dykes, suggest that the low δ18O values of olivine phenocrysts in Dykes 2 and 3 resulted from carbonate melt/fluid exsolution from a common progenitor melt. These lines of evidence combined with the overlapping emplacement ages and Sr–Nd isotope compositions of the aillikites and carbonatites in this area suggest that these exsolved carbonate melts probably contributed to the formation of the Tarim carbonatites, thus supporting a close petrogenetic relationship between aillikites and carbonatites. [ABSTRACT FROM AUTHOR]

Porphyry Cu–Au ores areamong the important types of porphyry deposits. Some of these are enriched in Pd and Pt, which in some cases have economic potential for PGE (platinum group element) recovery. The behaviour of PGE and S‐saturation in mafic intrusions associated with porphyry deposits are, however, poorly constrained. Here we investigate the PGE concentrations of gabbroic intrusions from Akcha, Beleuti, and Kalmakyr in the Almalyk porphyry Cu–Au ore field in Uzbekistan through Ni–S analyses employing fire assay‐isotope dilution method. The results reveal extremely high Pd/Ir ratio and a negative Ru anomaly for the Beleuti and Akcha gabbro which we attribute to fractional crystallization of olivine and Ru–Os–Ir alloys. The extremely high Cu/Pd ratio (2.56 × 105–2.98 × 106) and depleted PGE contents of the Kalmakyr gabbro possibly represent immiscible separation of sulphide. During the emplacement of the parental magma of Kalmakyr gabbro, crustal contamination might have resulted in S‐saturation and sulphide segregation. Sulphide‐bearing crust was remobilized during the increasing maturity of the island and long‐lived arc magmatism, which released the sulphide into the hydrothermal system of the porphyry deposit. We propose that this process favoured the enrichment of Pt–Pd and sulphide in the Kalmakyr porphyry Cu–Au deposit. [ABSTRACT FROM AUTHOR]

The bimodal intermediate‐felsic suites are rare, and their petrogenesis remains unsolved. Here, we report a bimodal intermediate‐felsic magmatic suite from East Junggar (NW China) composed of rhyolites, basaltic andesites, and andesites. The basaltic andesites and andesites are porphyritic with phenocrysts predominantly of plagioclase. The rhyolites are porphyritic with phenocrysts of alkali‐feldspar, quartz, and minor plagioclase. LA–ICP–MS zircon U–Pb dating yielded an age of 284 ± 2 Ma for rhyolites. The basaltic andesites and andesites show SiO2 ranging from 54.67 to 58.26 wt%, and exhibit moderate TiO2 (1.45–1.77 wt%), and K2O (1.59–2.07 wt%) with low MgO (1.51–2.25 wt%). They display enrichment in HFSE and LILE together with negative Th, Nb, Ta, Ti anomalies, and exhibit low 87Sr/86Sr(t) ratios (0.7040–0.7046), high positive εNd(t) values (+5.82 to +6.16) and young TDM ages (<0.6 Ga). The rhyolites exhibit highSiO2(>75 wt%), negative Nb, Ta anomalies and significant depletion in Ba, Eu, Sr, Ti, and P. They also show high εNd(t) values (+5.51 to +7.08) and young TDM ages (<0.6 Ga), which are close to those of the intermediate rocks. Except for elements dominantly controlled by fractional crystallization, the other trace elements of the bimodal suite display similar patterns. Based on these characteristics, the MELTS simulation further suggests that the felsic rocks were possibly evolved from the intermediate magmas through fractional crystallization of feldspar, clinopyroxene, iron‐titanium oxide, and apatite. In contrast, the magmas parental to basaltic andesites were derived from the remelting of basaltic rocks underplated beneath the lower crust. The petrogenesis of this bimodal suite also provides new insights into Permian crustal reworking in the East Junggar, and suggest that the Junggar Ocean was closed prior to the Early Permian. [ABSTRACT FROM AUTHOR]

Despite the potential emissions of heavy metal pollution in Lake Caizi due to extensive agriculture, urban growth and fishing activities, the risk posed by metal concentrations to aquatic environments and human populations has not yet been studied. In this study we compared the concentrations of Hg, As, Pb, Cd, Cr, Cu and Zn in water, sediment, and economic fish species with different habitat preferences and trophic guilds across important fishery areas in Lake Caizi, located on the northern shore of the Yangtze River, Southeast China. The concentrations of Cr in water were found approximately 6 times higher than the safety thresholds established by international legislation. Cr, Zn, As and Cd concentrations in sediments surpassed the background values for Yangtze River basin in Anhui Province. However, all the studied fish species in Lake Caizi had metal concentrations lower than legislation thresholds established by China and international organizations. Heavy metal concentrations were found to be significantly higher in demersal (inhabiting near the sediments) and piscivorous (possessing higher trophic level) fishes than in pelagic/benthopelagic (inhabiting the upper and lower water column) and herbivorous/planktivorous (possessing lower trophic level) fishes. Our finding demonstrated that the metal concentrations in fishes are simultaneously influenced by the habitat and bio-accumulation through the food chain. According to target hazard quotient (THQ) calculations for heavy metal contents in the muscles of fish species, all the determined heavy metals gave THQ values lower than 1, suggesting the inexistence of health risks from the intake of fishes from Lake Caizi. [ABSTRACT FROM AUTHOR]

The fall webworm, Hyphantria cunea (Drury) (Lepidoptera: Arctiidae), is a major invasive pest in China, where it seriously threatens fruit and ornamental trees and windbreak systems. An auto-contamination trap-strips system was designed to disseminate Beauveria bassiana for biological control. The standard trap consisted of a yellow or green trap with a width no larger than 30 cm and with B. bassiana inside it. Therefore, the trap-strips provided an appropriate microenvironment for the fall webworm to pupate, and an acceptable humidity for B. bassiana to infect and reproduce. The average infection rates of the trap-strips systems were more than 90%. The present study demonstrated a practical application of how physical and biological control of this pest can be conducted efficiently and economically. [ABSTRACT FROM AUTHOR]

Removal of heavy metals (e.g., Cd) from contaminated water using waste-converted adsorbents is promising, but the efficiency still needs to be improved. Here, we prepared a functional biochar composite as novel Cd adsorbents by co-pyrolysis of two typical solid wastes, i.e., agricultural corn straw and industrial fly ash. The adsorption behavior and mechanism were investigated using batch and column adsorption experiments and modern characterization techniques. Results showed that alkali-modified fly ash (AMFA) was loaded onto the surface of the corn straw biochar as some fine particle forms, with quartz (SiO 2) and silicate being the main mineral phases on the surface. The maximum sorption capacity fitted by Langmuir model for functionalized biochar composite (FBC700) was up to 137.1 mg g−1, which was 7.7 times higher than that of the original corn straw biochar (BC700). Spectroscopic analysis revealed that adsorption mechanisms of Cd onto the FBC700 included mainly precipitation and ion exchange, with complexation and Cd-π interaction also contributing. The AMFA could effectively improve the mineral precipitation with Cd. The adsorption columns filled with FBC700 exhibited a longer breakthrough time than that filled with BC700. The adsorption capacity calculated by Thomas model for FBC700 was also approximately 6.0 times higher than that for BC700, showing that FBC700 was more suited to practical applications. This study provided a novel perspective for recycling solid wastes and treating Cd-contaminated water. [Display omitted] • FBC700 was successfully prepared by co-pyrolysis of corn straw and fly ash waste. • Mineral precipitation and ion exchange dominated adsorption of Cd2+. • Silicon in FA played an important role in the adsorption of Cd2+ by FBC700. • FBC700 has efficient adsorption capacity and potential for cadmium. • A new strategy for recycling solid wastes and treating wastewater was obtained. [ABSTRACT FROM AUTHOR]

The article talks about the orogenic event of North Qinling Terrain, understanding the evolution of tectonic plates before the amalgamation of North China Block and South China Block along the Mianxian-Lueyang suture zone. It talks about the spread of the oceanic crust, subduction, collision that leads to the closure of Shang-Dan Paleotethys, different types of granites, leucogranite and felsic intrusion linked to continental crust.

Some insects use host and mate cues, including odor, color, and shape, to locate and recognize their preferred hosts and mates. Previous research has shown that the Asian longicorn beetle, Anoplophora glabripennis (Motschulsky), uses olfactory cues to locate host plants and differentiate them from non-host plants. However, whether A. glabripennis adults use visual cues or a combination of visual and olfactory cues remains unclear. In this study, we tested the host location and recognition behavior in A. glabripennis, which infests a number of hardwood species and causes considerable economic losses in North America, Europe and Asia. We determined the relative importance of visual and olfactory cues from Acer negundo in host plant location and recognition, as well as in the discrimination of non-host plants (Sabina chinensis and Pinus bungeana), by female and male A. glabripennis. Visual and olfactory cues from the host plants (A. negundo), alone and combined, attracted significantly more females and males than equivalent cues from non-host plants (S. chinensis and P. bungeana). Furthermore, the combination of visual and olfactory cues of host plants attracted more adults than either cue alone, and visual cues alone attracted significantly more adults than olfactory cues alone. This finding suggests that adult A. glabripennis has an innate preference for the visual and/or olfactory cues of its host plants (A. negundo) over those of the non-host plant and visual cues are initially more important than olfactory cues for orientation; furthermore, this finding also suggests that adults integrate visual and olfactory cues to find their host plants. Our results indicate that different modalities of host plant cues should be considered together to understand fully the communication between host plants and Asian longhorned beetles. [ABSTRACT FROM AUTHOR]

This paper describes the development of a portable microfluidic chip based on a surface-enhanced Raman spectroscopy (SERS) sensor for crystal violet analysis. A Y-shape microfluidic chip with a staggered herringbone structure was designed to efficiently mix the analyte and SERS active silver colloid. The subsequent detection of the analyte was performed on the microfluidic chip by a portable Raman system. Compared with other methods, this sensor is easy to operate and is expected to have applications for rapid and sensitive on-site analysis. A good linear correlation over the concentration range of 10 to 750 nM of crystal violet with a correlation coefficient of 0.992 was obtained. The recovery was between 98.6% and 102.9% for crystal violet in river water with relative standard deviations between 2.43% and 4.26%. [ABSTRACT FROM AUTHOR]

ABSTRACT A novel model based on a radial basis function neural network (RBF NN), chaos theory, self-adaptive particle swarm optimization (PSO), and a clustering method is proposed to predict the gas solubility in polymers; this model is hereafter called CSPSO-C RBF NN. To develop the CSPSO-C RBF NN, the conventional PSO was modified with chaos theory and a self-adaptive inertia weight factor to overcome its premature convergence problem. The classical k-means clustering method was used to tune the hidden centers and radial basis function spreads, and the modified PSO algorithm was used to optimize the RBF NN connection weights. Then, the CSPSO-C RBF NN was used to investigate the solubility of N2 in polystyrene (PS) and CO2 in PS, polypropylene, poly(butylene succinate), and poly(butylene succinate- co-adipate). The results obtained in this study indicate that the CSPSO-C RBF NN was an effective method for predicting the gas solubility in polymers. In addition, compared with conventional RBF NN and PSO neural network, the CSPSO-C RBF NN showed better performance. The values of the average relative deviation, squared correlation coefficient, and standard deviation were 0.1282, 0.9970, and 0.0115, respectively. The statistical data demonstrated that the CSPSO-C RBF NN had excellent prediction capabilities with a high accuracy and a good correlation between the predicted values and the experimental data. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 3825-3832, 2013 [ABSTRACT FROM AUTHOR]

To replace costly and time-consuming experimentation in laboratory, a novel solubility prediction model based on chaos theory, self-adaptive particle swarm optimization (PSO), fuzzy c-means clustering method, and radial basis function artificial neural network (RBF ANN) is proposed to predict CO2 solubility in polymers, hereafter called CSPSO-FC RBF ANN. The premature convergence problem is overcome by modifying the conventional PSO using chaos theory and self-adaptive inertia weight factor. Fuzzy c-means clustering method is used to tune the hidden centers and radial basis function spreads. The modified PSO algorithm is employed to optimize the RBF ANN connection weights. Then, the proposed CSPSO-FC RBF ANN is used to investigate solubility of CO2 in polystyrene (PS), polypropylene (PP), poly(butylene succinate) (PBS) and poly(butylene succinate-co-adipate) (PBSA), respectively. Results indicate that CSPSO-FC RBF ANN is an effective method for gas solubility in polymers. In addition, compared with conventional RBF ANN and PSO ANN, CSPSO-FC RBF ANN shows better performance. The values of average relative deviation (ARD), squared correlation coefficient ( R2) and standard deviation (SD) are 0.1071, 0.9973 and 0.0108, respectively. Statistical data demonstrate that CSPSO-FC RBF ANN has excellent prediction capability and high-accuracy, and the correlation between prediction values and experimental data is good. [ABSTRACT FROM AUTHOR]

Using a nylon membrane as the supporting material, a simple, high sensitivity solid-phase surface fluorescence system has been assembled. Compared with other supporting materials, the nylon membrane is easily available and inexpensive. According to SEM images and the characteristics of other membranes to enrich the analyte, it can be concluded that the nylon membrane concentrates the analyte. Several parameters such as the photomultiplier tube voltage, slit widths, incident angle, pore size of the membrane, and analysis conditions (pH, filtration volume, flow rate) of this system were optimized. The 2-naphthalene sulfonic acid was chosen to be the analyte. Satisfactory analytical figures were obtained under the optimized experimental conditions which included a linear calibration range from 1.0 × 10−3to 0.16 µg/mL; a relative standard deviation of 5.67% (n = 7) at a concentration of 0.02 µg/mL; and a limit of detection equal to 8.55 × 10−4 µg/mL. [ABSTRACT FROM AUTHOR]

A four-layer fuzzy neural network (FNN) model combining particle swarm optimization (PSO) algorithm and clustering method is proposed to predict the solubility of gases in polymers, hereafter called the CPSO-FNN, which combined fuzzy theory's better adaptive ability, neural network's capability of nonlinear and PSO algorithm's global search ability. In this article, the CPSO-FNN model has been employed to investigate solubility of CO2 in polystyrene, N2 in polystyrene, and CO2 in polypropylene, respectively. Results obtained in this work indicate that the proposed CPSO-FNN is an effective method for the prediction of gases solubility in polymers. Meanwhile, compared with traditional FNN, this method shows a better performance on predicting gases solubility in polymers. The values of average relative deviation, squared correlation coefficient ( R2) and standard deviation are 0.135, 0.9936, and 0.0302, respectively. The statistical data demonstrate that the CPSO-FNN has an outstanding prediction accuracy and an excellent correlation between prediction values and experimental data. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 [ABSTRACT FROM AUTHOR]

As the largest tributary flowing into Chaohu Lake, China, the Hangbu–Fengle River (HFR) has an important impact on the aquatic environment security of the lake. However, existing information on the potential risks of heavy metals (HMs) in HFR sediments was insufficient due to the lack of bioavailability data on HMs. Hence, geochemical fractionation, bioavailability, and potential risk of five HMs (Cr, Cu, Zn, Cd, and Pb) in HFR sediments were investigated by the combined use of the diffusive gradient in thin-films (DGT), sequential extraction (BCR), as well as the physiologically based extraction test (PBET). The average contents of Cd and Zn in the HFR Basin were more than the background values in the sediments of Chaohu Lake. A large percentage of BCR-extracted exchangeable fraction was found in Cd (8.69%), Zn (8.12%), and Cu (8.05%), suggesting higher bioavailability. The PBET-extracted fractions of five HMs were all almost closely positively correlated with their BCR-extracted forms. The pH was an important factor affecting the bioavailability of HMs. The average DGT-measured contents of Zn, Cd, Cr, Cu, and Pb were 28.07, 7.7, 3.69, 2.26, 0.5 μg/L, respectively. Only DGT-measured Cd significantly negatively correlated with Eh, indicating that Cd also had a high release risk under reducing conditions, similar to the risk assessment results. Our results could provide a reference for evaluating the potential bioavailabilities and ecological hazards of HMs in similar study areas. [Display omitted] • Zn and Cd in sediments were all present at relatively high levels. • BCR, in vitro PBET and DGT were used to assess metal bioavailability in sediments. • pH is the important factor influencing the metal bioavailability in sediments. • Cd has a potential risk of being released from sediments in the study area. Capsule: The study helps to better understand for effectively evaluating the bioavailability and potential hazards of metal elements in river sediments. [ABSTRACT FROM AUTHOR]

Polychlorinated dibenzothiophenes (PCDTs) are a class of compounds structurally similar to dioxins that possess various toxicological impacts on living organisms. Unfortunately, information on the levels of PCDTs in freshwater lakes in China is still scarce. In this work, the occurrence of 14 congeners of PCDTs in different matrices (i.e., sediment, suspended particulate matter (SPM), and water) of Chaohu Lake was investigated. It was determined that the concentrations of 14 PCDTs (Σ 14 PCDTs) in the sediment, SPM, and surface water were 0.40–3.55 ng g−1 (dry weight, d.w.), 0.38–2.95 ng·g−1 d.w., and 0.34–2.61 ng L−1, respectively. The dominant congener found in sediments was 1,2,3,4,7-penta-CDT (19.54%), and 1,3,9-tri-CDT was the predominant congener in SPM (19.13%) and water (20.08%). Medium- and high-chlorinated PCDTs were detected as the major compounds in sediments and SPM. The low-chlorinated PCDTs (e.g., mono-CDTs) have higher relative percentages in the water than those detected in the sediment samples. The annual Σ 14 PCDT input of the eight main tributaries to Chaohu Lake was 19.90 kg. A strong linear correlation between the Σ 14 PCDT levels and the organic carbon (OC) content demonstrated that OC had an important influence on the PCDT redistribution in Chaohu Lake. In addition, the organic carbon normalized partitioning coefficient (log K OC) of PCDTs in the SPM-water system in Chaohu Lake was 1.95–2.49 mL g−1, and correlations between log K OC and other typical environment-related properties of PCDTs were established. This study provided useful data on the evaluation of ecological risks of PCDTs in Chaohu Lake. [Display omitted] • This work suggested the unambiguous pollution of fourteen PCDTs in Chaohu Lake. • Lower-chlorinated PCDTs have the higher relative percentages in the surface water. • OC posed significant effects on the redistribution of PCDTs in Chaohu Lake. • The Σ 14 PCDTs input of eight main tributaries to Chaohu Lake was 19.90 kg per year. • The log K OC of PCDTs in the water-SPM system ranged in 1.95–2.49 mL g−1 in Chaohu Lake. [ABSTRACT FROM AUTHOR]

The article focuses on findings of a study on early paleozoic magmatism and crustal evolution in the North Qinling Orogen. Topics include multi-phase tectonic-magmatic events found in North Qinling orogenic belt; chronlogical and chemical evidence for the evolution of the basement and tectonic provenance of the Qinling orogenic belt; and a comparison with the magmatism and crustal evolution of the adjacent terrains.

The agricultural land-atmospheric dustfall-plant system around the mining area is at high risks of heavy metal pollution caused by mining-smelting activities. In this study, 118 samples (including rhizospheric soils, background soils, soil-forming parent rocks, crops, vegetables, medicinal plants and atmospheric dustfall) were collected nearby Tongling Cu-Fe-Au mining area, Eastern China. We studied the concentrations, migration, sources, and health risks through consumption of two main crops (corn and rice), six kinds of vegetables, and medicinal plants (Fengdan, Paeonia ostii) for six metal elements (Cu, Zn, Cr, Cd, Pb and Hg). Results revealed Cr and Cd in soils, and Cd, Cr, Pb, Cu and Zn in dustfall showed a relatively high contamination degree. The mean contents of Cr and Pb in corn kernels, as well as Cd, Cr and Pb in rice grains and all vegetables, and Cr in Fengdan cortex moutan exceeded the corresponding food safety limits in China. The transfer capability of Cr in corn kernels and rice grains, Pb in edible vegetables, and Cd in cortex moutan were the strongest, respectively. Health risk assessment results showed Cr had the greatest non-carcinogenic risk, followed by Pb and Cd. The results of pearson's correlation analysis (CA), hierarchical cluster analysis (HCA), and principal component analysis (PCA) indicated Zn-Cr, Pb and Cd-Cu-Hg in the plants might derive from different geochemical end-members. Source apportionment based on lead isotope showed that mining-smelting activities were the major source of Pb in atmospheric dustfall and agricultural soils, with the average contribution rates of 66% and 50%, respectively. Vehicle emissions from diesel fuels (50%–68%) and mining-smelting activities (16%–25%) contributed mainly to Pb accumulation in plants. Hence, our study suggested the accumulations of Pb in plants might be mainly from the direct foliar uptake of atmospheric Pb related to vehicle emissions and mining-smelting activities. Image 1 • Cr and Cd in soils and dustfall were all present at relatively high levels. • Cr, Cd, and Pb have potential health risks via consumption of edible plants. • Sources of Cr and Cd in soil-dustfall-plant system are different. • Diesel vehicle emission was the dominant Pb source in plants. The research expands the application of lead isotope in tracing the sources of heavy metals in the more complex soil-dustfall-plant system for the mine environment. [ABSTRACT FROM AUTHOR]

To clarify the infection approach of Diplodia sapinea, a pathogen that causes tip blight of Pinus tabulaeformis, the infection process of the pathogen in needles was observed using scanning electron microscopy (SEM). In addition, the disease incidence on branches damaged by Aphrophora flavipes (Hemiptera: Cercopidae) and Dioryctria splendidella (Lepidoptera: Pyralidae) in the forest was also investigated. Then, branches and needles of P. tabulaeformis were inoculated using the D. sapinea spore suspension under indoor and field conditions. The results showed that the damage caused by A. flavipes could aggravate the occurrence of tip blight of P. tabulaeformis to some extent. Moreover, the pathogen could also penetrate 1‐, 2‐ and 3‐year‐old pine needles through stomata in the field. The pathogen infected the 1‐year‐old branches first and then gradually spread to 2‐ and 3‐year‐old branches. [ABSTRACT FROM AUTHOR]

The authors describe a microparticle-based system for the detection of the fluoroquinolone antibiotic ciprofloxacin. The method is using the tris(dibenzoylmethane)(1,10-phenanthroline)europium(III) luminophore in polystyrene microparticles along with a molecularly imprinted polymer (MIP) for ciprofloxacin. If ciprofloxacin is captured by the MIP, it quenches the fluorescence of the luminophores. Fluorescence drops linearly in the 0.5–100 μg L−1 ciprofloxacin concentration range, and the detection limit is 92 ng L−1. The method was applied to the analysis of fish samples to assess the analytical performance of the probe. Recoveries ranged from 85.4 to 86.6%, and relative standard deviations between 2.1 and 3.9% (for n = 5). [ABSTRACT FROM AUTHOR]

Being one type of post-translational modifications (PTMs), protein lysine succinylation is important in regulating varieties of biological processes. It is also involved with some diseases, however. Consequently, from the angles of both basic research and drug development, we are facing a challenging problem: for an uncharacterized protein sequence having many Lys residues therein, which ones can be succinylated, and which ones cannot? To address this problem, we have developed a predictor called pSuc-Lys through (1) incorporating the sequence-coupled information into the general pseudo amino acid composition, (2) balancing out skewed training dataset by random sampling, and (3) constructing an ensemble predictor by fusing a series of individual random forest classifiers. Rigorous cross-validations indicated that it remarkably outperformed the existing methods. A user-friendly web-server for pSuc-Lys has been established at http://www.jci-bioinfo.cn/pSuc-Lys , by which users can easily obtain their desired results without the need to go through the complicated mathematical equations involved. It has not escaped our notice that the formulation and approach presented here can also be used to analyze many other problems in computational proteomics. [ABSTRACT FROM AUTHOR]