Hydrous mantle plume promoted the generation of continental flood basalts in the Tarim large igneous province.

Recent research on the water content of large igneous provinces (LIPs) has revealed that water has a significant impact on the formation of LIPs. However, most studies focus on the water content of mafic-ultramafic rocks, while relatively little attention has been paid to the water content of continental flood basalts (CFB), which form the major part of LIPs and are characterized by huge volumes (> 1 × 105 km3) and short eruption times. Here, we determined water contents of clinopyroxene crystals from the Akesu diabase, which is co-genetic with flood basalts of the Tarim LIP in China. Based on these measurements, we obtained a water content of higher than 1.23 ± 0.49 wt.% for the parental magma to the Tarim CFB and a minimum water content of 1230 ± 490 ppm for the mantle source, thus indicating the presence of a hydrous mantle plume. Combined with previous studies, our results suggest that water plays a key role in the formation of the Tarim LIP. Additionally, the whole-rock compositions of the Akesu diabase indicate a contribution of pyroxenite in the mantle source. This is consistent with a model, in which water was brought into the Tarim mantle plume by a subducted oceanic plate that entered the deep mantle.

Electrical conductivity of melts: implications for conductivity anomalies in the Earth's mantle.

Magmatic liquids, including silicate and carbonate melts, are principal agents of mass and heat transfer in the Earth and terrestrial planets, and they play a crucial role in various geodynamic processes and in Earth's evolution. Electrical conductivity data of these melts elucidate the cause of electrical anomalies in Earth's interior and shed light on the melt structure. With the improvement in high-pressure experimental techniques and theoretical simulations, major progress has been made on this front in the past several decades. This review aims to summarize recent advances in experimental and theoretical studies on the electrical conductivity of silicate and carbonate melts of different compositions and volatile contents under high temperature and pressure. The electrical conductivity of silicate melts depends strongly on temperature, pressure, water content and the ratio of non-bridging oxygens to tetrahedral cations (NBO/T). By contrast, the electrical conductivity of carbonate melts exhibits a weak dependence on temperature and pressure due to their fully depolymerized structure. The electrical conductivity of carbonate melts is higher than that of silicate melts by at least two orders of magnitude. Water can increase electrical conductivity significantly and reduce the activation energy of silicate melts. Conversely, this effect is weak for carbonate melts. In addition, the replacement of alkali-earth elements (Ca2+ or Mg2+) with alkali elements causes a significant decrease in the electrical conductivity of carbonate melts. A distinct compensation trend is revealed for the electrical conductivity of silicate and carbonate melts under anhydrous and hydrous conditions. Several important applications of laboratory-based melt conductivity are introduced in order to understand the origin of high-conductivity anomalies in the Earth's mantle. Perspectives for future studies are also provided.

Tracing the subducting Pacific slab to the mantle transition zone with hydrogen isotopes.

Hydrogen isotopes have been widely used as powerful tracers to understand the origin of terrestrial water and the water circulation between the surface and the deep interior of the Earth. However, further quantitative understanding is hindered due to a lack of observations about the changes in D/H ratios of a slab during subduction. Here, we report hydrogen isotope data of olivine-hosted melt inclusions from active volcanoes with variable depths (90‒550 km) to the subducting Pacific slab. The results show that the D/H ratio of the slab fluid at the volcanic front is lower than that of the slab fluid just behind the volcanic front. This demonstrates that fluids with different D/H ratios were released from the crust and the underlying peridotite portions of the slab around the volcanic front. The results also show that the D/H ratios of slab fluids do not change significantly with slab depths from 300 to 550 km, which demonstrates that slab dehydration did not occur significantly beyond the arc. Our estimated δD‰ value for the slab materials that accumulated in the mantle transition zone is > - 90‰, a value which is significantly higher than previous estimates.

Research Progress in Treatment of Chemical Liver Injury with Chinese Medicine Based on Metabolomics / 中国实验方剂学杂志

Liver， as a critical organ of metabolism and detoxification， can be damaged by viral infection， drug abuse， and heavy drinking. Liver diseases pose a serious threat to people's health and life in China.At present， drug therapy has been primarily adopted clinically in the treatment of the liver injury.In-depth investigation of the mechanism of liver-protective drugs is of great significance to the prevention and treatment of clinical liver diseases.In recent years， with the development of the medical industry in China， an increasing number of studies have focused on the treatment of liver injury with Chinese medicine.Compared with western medicine， Chinese medicine is advantageous in few side effects and overall regulation， which plays a pivotal role in liver protection.However， its underlying mechanism in liver protection still needs to be further studied due to its complex compositions and diverse targets.Metabolomics， a new approach to studying the metabolic pathway of biological systems， provides integral and systematic views in the investigation of liver protection with Chinese medicine. By virtue of metabolomics， the mechanism of Chinese medicine in multi-target and multi-pathway liver protection can be analyzed comprehensively， and the corresponding biomarkers can also be screened out. The authors analyzed the studies of the treatment of chemical liver injury models induced by carbon tetrachloride （CCl4）， dimethylnitrosamine （DMN）， α-naphthyl isothiocyanate （ANIT）， and alcohol by Chinese medicinal compounds， single herbal medicines， and monomers of Chinese medicine based on metabolomics， and summarized the biomarkers and related metabolic pathways of Chinese medicine in the intervention of each type of liver injury， aiming at providing a reference for the further research and clinical application in the treatment of different types of liver injuries by Chinese medicine.

High H2O Content in Pyroxenes of Residual Mantle Peridotites at a Mid Atlantic Ridge Segment.

Global correlations of mid-ocean-ridges basalt chemistry, axial depth and crustal thickness have been ascribed to mantle temperature variations affecting degree of melting. However, mantle H2O content and elemental composition may also play a role. How H2O is distributed in the oceanic upper mantle remains poorly constrained. We tackled this problem by determining the H2O content of orthopyroxenes (opx) and clinopyroxenes (cpx) of peridotites from a continuous lithospheric section created during 26 Ma at a 11°N Mid-Atlantic Ridge segment, and exposed along the Vema Transform. The H2O content of opx ranges from 119 ppm to 383 ppm; that of cpx from 407 ppm to 1072 ppm. We found anomalous H2O-enriched peridotites with their H2O content not correlating inversely with their degree of melting, although H2O is assumed to be incompatible during melting. Inverse correlation of H2O with Ce, another highly incompatible component, suggests post-melting H2O enrichment. We attribute a major role to post-melting temperature-dependent diffusion of hydrogen occurring above the melting region, where water-rich melt flows faster than residual peridotites through dunitic conduits cross-cutting the uprising mantle. Accordingly, estimates of the H2O content of the MORB mantle source based on H2O in abyssal peridotites can be affected by strong uncertainties.

Buoyant hydrous mantle plume from the mantle transition zone.

Magmatism at some intraplate volcanoes and large igneous provinces (LIPs) in continental areas may originate from hydrous mantle upwelling (i.e. a plume) from the mantle transition zone (MTZ) at 410-660 km depths in the Earth's deep interior. However, the ultimate origin of the magmatism, i.e. why mantle plumes could have been generated at the MTZ, remains unclear. Here, we study the buoyancy of a plume by investigating basalts from the Changbaishan volcano, beneath which a mantle plume from the hydrous MTZ is observed via seismology. Based on carefully determined water contents of the basalts, the potential temperature of the source mantle is estimated to be 1310-1400 °C, which is within the range of the normal upper mantle temperature. This observation suggests that the mantle plume did not have a significant excess heat, and that the plume upwelled because of buoyancy resulting from water supplied from the Pacific slab in the MTZ. Such a hydrous mantle plume can account for the formation of extremely hydrous LIP magmatism. The water was originally sourced from a stagnant slab and stored in the MTZ, and then upwelled irrespective of the presence or absence of a deep thermal plume.

Water in the upper mantle and deep crust of eastern China: concentration, distribution and implications.

Understanding the concentration and distribution of water in the Earth's mantle plays a substantial role in studying its chemical, physical and dynamic processes. After a decade of research, a comprehensive dataset of water content in upper-mantle samples has been built for eastern China, which is now the only place with water-content data from such diverse types of natural samples, and provides an integrated picture of the water content and its distribution in the upper mantle at a continental scale. The main findings include the following: (i) the temporal heterogeneity of the water content in the lithospheric mantle from early Cretaceous (∼120 Ma) to Cenozoic (<40 Ma) was tightly connected with the stability of the North China Craton (from its destruction to its consolidation); (ii) the heterogeneous water content in the Cenozoic lithospheric mantle beneath different blocks of eastern China was not only inherited from tectonic settings from which they came, but was also affected later by geological processes they experienced; (iii) the distinct water content between the lowermost crust and lithospheric mantle of eastern China and its induced rheological contrast at the base of the crust indicate that the continental crust-mantle boundary could behave either in a coupled or decoupled manner beneath different areas and/or at different stages; (iv) the alkali basalts of eastern China demonstrate a heterogeneous distribution of water content in the mantle; local and regional comparisons of the water content between the lithospheric mantle and basalts' source indicate that the Cenozoic alkali basalts in eastern China were not sourced from the lithospheric mantle. Instead, the inferred high water contents in the mantle sources suggest that the Cenozoic eastern China basalts were likely sourced from the mantle transition zone (MTZ); and (v) both oceanic and continental crusts may carry a certain amount of water back into the deep mantle of eastern China by plate subduction. Such recycled crustal materials have not only created a local water-rich zone, but have also introduced crustal geochemical signatures into the mantle, both accounting for crustal geochemical imprints in the intra-plate magmatic rocks of eastern China.

Mantle hydration and the role of water in the generation of large igneous provinces.

The genesis of large igneous provinces (LIP) is controlled by multiple factors including anomalous mantle temperatures, the presence of fusible fertile components and volatiles in the mantle source, and the extent of decompression. The lack of a comprehensive examination of all these factors in one specific LIP makes the mantle plume model debatable. Here, we report estimates of the water content in picrites from the Emeishan LIP in southwestern China. Although these picrites display an island arc-like H2O content (up to 3.4 by weight percent), the trace element characteristics do not support a subduction zone setting but point to a hydrous reservoir in the deep mantle. Combining with previous studies, we propose that hydrous and hot plumes occasionally appeared in the Phanerozoic era to produce continental LIPs (e.g., Tarim, Siberian Trap, Karoo). The wide sampling of hydrous reservoirs in the deep mantle by mantle plumes thus indicates that the Earth's interior is largely hydrated.

High water content in primitive continental flood basalts.

As the main constituent of large igneous provinces, the generation of continental flood basalts (CFB) that are characterized by huge eruption volume (>10(5) km(3)) within short time span (<1-3 Ma) is in principle caused by an abnormally high temperature, extended decompression, a certain amount of mafic source rocks (e.g., pyroxenite), or an elevated H2O content in the mantle source. These four factors are not mutually exclusive. There are growing evidences for high temperature, decompression and mafic source rocks, albeit with hot debate. However, there is currently no convincing evidence of high water content in the source of CFB. We retrieved the initial H2O content of the primitive CFB in the early Permian Tarim large igneous province (NW China), using the H2O content of ten early-formed clinopyroxene (cpx) crystals that recorded the composition of the primitive Tarim basaltic melts and the partition coefficient of H2O between cpx and basaltic melt. The arc-like H2O content (4.82 ± 1.00 wt.%) provides the first clear evidence that H2O plays an important role in the generation of CFB.

Establishment and evaluation of the review criteria of automatic urine analysis workstations / 中华检验医学杂志

Objective To establish the proper review rules for the microscopic screening of urine samples tested by automatic urinalysis work station.Methods A total of 3 154 random urine samples were enrolled to establish and validate review rules .All the samples were collected from the inpatients and outpatients of Shanghai First People′s Hospital from March to May 2013 and tested by urinalysis work station.Three thousands one hundred and fifty four urine samples were firstly tested by urinalysis work station,including both urine dry chemical analyzer and urine sediments analyzer .Then each urine sample was examined microscopically by two technicians-in-charge using double-blind method.The average results from the two technicians were used as review results .Compared with review results ,the review rules were set up.According to different test methods by automatic urinalysis work station , four microscopic review protocols were defined:(1)Protocol 1:based on chemistry results only ,microscopy review was performed when any of WBC,RBC,PRO and NIT was positive;(2)Protocol 2:based on urine sedimental analysis only ,microscopy review was performed when any of WBC ,RBC and CAST count was over upper limit of the reference range;(3)Protocol 3:if any of BLD ,RBC,LEU,WBC was different between two systems ,or quantitative results had two or more than two gradient differences ,microscopy review was performed;(4) Protoco1 4:if any of BLD, RBC,LEU ,WBC was different between two systems , or CAST was over upper limit of the reference range , or alarm appeared , microscopic review was performed .400 randomly selected urine samples were tested to validate the review rules .Omission diagnostic rate and review rate were used to evaluate the rules .Results According to the review rules,the positive samples rate was 43.47%(1 371/3 154) and the negative rate was 56.53%( 1 783/3 154 );Positive samples were composed of RBC ( 55.58%) , WBC ( 59.66%) and CAST(6.42%).The review rates of four protocols were 44.48%(1 403/3 154),45.69%(1 441/3 154), 26.09%(823/3 154),28.95%(913/3 154),respectively.The false negative rates (omission diagnostic rates)were 7.13%(225/3 154),4.53%(143/3 154),2.73%(86/3 154) and 1.02%(32/3 154), respectively .Protocol 4 was selected as an ideal plan.Additional 400 urine samples were tested using protocol 4 in order to confirm the review rule.The review rate, false negative rate were 26.25%(105/400), 0.75%( 3/400 ), respectively.After image review revised, the review rate was 14.50%(58/400).Conclusion This study formulates that the automatic urine analysis workstation review rules have clinical maneuverability and validity.

[Non-surgical treatment for nonresectable advanced hepatic alveolar echinococcosis].

OBJECTIVE: To investigate the therapeutic methods of nonresectable advanced hepatic alveolar echinococcosis. METHODS: A retrospective study was carried out to analyze 25 cases of nonresectable advanced hepatic alveolar echinococcosis in the Fourth Hospital of PLA from 2006 to 2009. RESULTS: There were 18 male and 7 female patients with a mean age of 41 years. Twelve cases were treated with albendazole alone. Eleven patients were treated with albendazole combined with percutaneous puncture. Two cases were treated with albendazole combined with other intervention. A course of albendazole administration lasted 2 weeks with a dose of 15-20 mg/(kg x d) for 3 course in general. Eighteen patients were followed up for 1-4 years. In albendazole group, 2 cases were effective and 7 cases were symptom-improved. Five patients got improved and 2 cases showed effective in albendazole combined with percutaneous puncture group. Two cases of albendazole combined with intervention group showed no efficacy. CONCLUSIONS: Long-term use of albendazole is the main treatment for nonresectable advanced hepatic alveolar echinococcosis.

Aging of air pollution control residues from municipal solid waste incinerator: role of water content on metal carbonation.

This work studies the effect of water content on the aging of APC residues, with a liquid to solid ratio (L/S) of 0.25 or 10, aged with or without exposure to ambient air. After the residue was mixed with water, CaSO4 and (Na,K)Al3(SO4)2(OH)6 in the raw sample yielded ettringite. When CO2 were available, this ettringite was further transformed to gypsum, calcite and possibly gibbsite. Experimental data revealed that the concentrations of Pb, Zn, Cd, Hg, and Cu fell with age, whereas that of Cr increased. Given L/S=10, excess Ca2+ ions were present in the suspension, so a precipitate of primarily calcite crystals of sizes under 5 microm formed on the air-water surface. This layer significantly reduced the rates of decline of Pb, Zn, Cd and Hg contents, and also reduced the increasing rate of Cr content in the suspension. This result follows from the mass transfer barrier of CO2 added at the air-water surface and the occurrence of subsequent chemical reactions in the suspension. An estimate of the mass transfer rate revealed that the rate-controlling step with L/S=10 was the dissolution and diffusion of CO2 in the bulk solution. However, at L/S=0.25, the rate-limiting step was the dissolution of metals from ash particles. Water content is a very important process factor, whose distribution in the sample, and the resulting competition between carbonate ion flux and heavy metal flux, govern the reaction time required during the natural aging process.

Leaching behavior of Pb and Zn in air pollution control residues and their modeling prediction.

Increasing attention has been paid to air pollution control (APC) residues in China recently due to the rising proportion of waste incineration and the hazardous characteristics of the residues, among which heavy metal leaching toxicity plays an important role. Leaching behavior and potential risk of Pb and Zn in the APC residues from a Shanghai municipal solid waste (MSW) incinerator was studied, based on the leaching tests under different conditions and theoretical calculation using a geochemical thermodynamic equilibrium model MINTEQA2. Results showed that, extractant species and liquid to solid (L/S) ratio predominantly controlled the leaching toxicity of Pb and Zn, while ionic strength, vibration method and leaching time had less effect on the metals release. Leachate/final pH determined the metal leaching behavior, which changed the speciation of heavy metals in the extraction system. The equilibrium aqueous speciation, precipitation-dissolution of Pb and Zn was investigated according to the model computation, which was well in agreement with the experimental results.