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The study investigates the practical application of cyclic wet/dry corrosion tests in simulated industrial atmospheres to assess the impact of chromium (Cr) on the protective properties of vanadium micro‐alloyed weathering steels. Two types of steels were examined: a V‐N steel and a V‐N‐Cr micro‐alloyed weathering steel. These steels were subjected to corrosion tests with 0.01 mol/L NaHSO3 at a pH range of 4.4–4.8 for varying durations. The findings indicate that the inclusion of Cr in the composition of vanadium micro‐alloyed weathering steel enhances corrosion resistance and leads to the accumulation of Cr in the inner rust layer. Furthermore, the distribution of corrosion‐resistant elements (Cr, Ni, Cu, P, and Mo) in V‐N and V‐N‐Cr steels is analyzed. The rust layer was observed to exhibit stratification in the corrosive environment, with the outer layers being dense and uniform, while the inner layers were porous and exhibited poor adhesion to the matrix. The study also delves into the anticorrosion mechanism of vanadium weathering steel using techniques such as X‐ray diffractometer, electron probe microanalysis, and potential‐phase diagram. [ABSTRACT FROM AUTHOR]

The direct ortho‐alkynylation of substituted phenylalanine has been successfully achieved through methoxyiminoacyl (MIA)‐mediated Pd‐catalyzed C−H functionalization. This innovative protocol showcases the ability to apply a diverse range of phenylalanine substrates, resulting in the efficient synthesis of alkynylation benzylamine derivatives with notable effectiveness. Computational investigations further revealed that the fluoride ion enhances the electropositivity of Pd(IV) and the interaction between C1 and C2 within the transition state of the reductive elimination, which significantly expedites the reductive elimination step in the alkynylation process. [ABSTRACT FROM AUTHOR]

In view of the problems existing in the current mine safety monitoring system, such as low real-time performance, unstable communication and easy interruption, sensor failure or over-limit power failure control time, etc, the characteristics of CAN bus, software engineering, Coal Mine Safety Monitoring System Upgrade and Transformation Technology Program (Coal Safety Supervision [2016] No.5) and the real underground environment of coal mine were investigated and analyzed in detail. A strong real-time communication scheme is designed, and the software and hardware of the system are designed. During the continuous operation of the system, abnormal data are not generated, sensor failure or over-limit power off time can be completed locally within 2 s, and the out-of-control can be completed within 5 s. The technical indicators comply with the General Technical Requirements for Coal Mine Safety Monitoring System (AQ 6201—2006).

The direct acetoxylation of substituted benzylamines has been accomplished through methoxyiminoacyl (MIA)‐mediated Pd‐catalyzed C−H functionalization. A diverse array of phenylalanine substrates is amenable to this protocol, providing acetoxylation benzylamine derivatives with good to high efficiency. Computational results revealed that HOAc enhanced the stability of Pd−O bond, which obviously accelerate the reductive elimination step of the acetoxylation process. [ABSTRACT FROM AUTHOR]

A new copper/silver-co-mediated three-component bicyclization of benzene-linked 1,6-enynes with ICF2CO2Et with TMSN3 was reported, and used to produce a wide range of hitherto unreported difluorinated tetrahydroindeno[1,2-c]azepine-3,6-diones with moderate to good yields. The mechanistic pathway consists of radical-induced 1,6-addition–cyclization, oxidative addition, reductive elimination, nitrene insertion and N–O cleavage, resulting in continuous multiple bond-forming events including C–C and C–N bonds to build up a 6/5/7 tricyclic framework. [ABSTRACT FROM AUTHOR]

A novel 3D Eu(III) metal–organic framework (Eu-MOF-1) formulated as [Eu(L)(H2O)(DMA)] (L = 2-(2-nitro-4-carboxylphenyl)terephthalic acid) has been successfully synthesized under solvothermal conditions and characterized by structural analyses. Eu-MOF-1 displays a new 3D framework containing EuIII ions, ligand L, and coordinated DMA molecules and water molecules. The fluorescence investigations indicate that Eu-MOF-1 emits bright red luminescence, and shows relatively high water stability and outstanding chemical stability under a relatively wide range of pH conditions. It is noteworthy that Eu-MOF-1 can quantitatively detect p-aminophenol (PAP) which is a metabolite of phenylamine in human urine. More significantly, Eu-MOF-1 is the first reported multi-responsive luminescent sensor for detecting the biomarker PAP, and MnVII and CrVI anions with high selectivity, sensitivity, recyclability and relatively low detection limits in aqueous solutions. Furthermore, the possible sensing mechanisms of Eu-MOF-1 for selective sensing have also been explored in detail. Eu-MOF-1 could be an ideal candidate as a multi-responsive luminescent sensor in biological and environmental areas. [ABSTRACT FROM AUTHOR]

Three novel Cd(II)/Zn(II) coordination polymers (CPs), namely [Cd(L)(BPDC)0.5H2O]·0.5H2O (1), [Zn2(L)2(BPDC)]·2H2O (2) and [Cd2(L)(BTC)H2O]·3H2O (3) (L = 4-(tetrazol-5-yl)phenyl-4,2′:6′,4′′-terpyridine, H2BPDC = 4,4′-biphenyldicarboxylic acid, and H3BTC = 1,3,5-benzenetricarboxylic acid), have been successfully synthesized and characterized. CP 1 and CP 2 display new two-dimensional double-layered honeycomb frameworks containing uncoordinated nitrogen atoms from pyridine and tetrazole rings, which can easily form hydrogen bonds with various analytes. CP 3 exhibits a 3D framework also with uncoordinated nitrogen atoms from pyridine and tetrazole rings. The fluorescence explorations indicate that CPs 1–3 exhibit strong blue luminescence and excellent chemical stability under a relatively wide range of pH conditions. It is worth noting that CPs 1–3 can quantitatively detect hippuric acid (HA), which is a metabolite of toluene in human urine, with high selectivity, sensitivity, fast response and relatively low detection limits. Moreover, the sensing mechanism of CPs 1–3 for HA can mainly be ascribed to fluorescence resonance energy transfer (FRET). CPs 1–3 could be ideal candidates as HA sensors in human urine samples for practical applications. Notably, to the best of our knowledge, we report for the first time Cd(II)/Zn(II)-based luminescent sensors for detecting HA in simulated urine. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: Azithromycin (AZM), a 15‐member macrolide antibiotic, has caused widespread pollution in China, where anaerobic digestion is the predominant wastewater treatment technology. However, the type of anaerobic sludge most suitable for treating antibiotic wastewater is unclear. Therefore, this study aimed to determine the response of anaerobic flocculent and granular sludge to AZM wastewater, and, using a high‐throughput sequencing technique, to explain the diverse microbial community structures. RESULTS: Anaerobic granular sludge provided better resistance to the decline of chemical oxygen demand (COD) removal caused by AZM and greater biodegradation efficiency than flocculent sludge. Furthermore, there was stronger resistance to AZM‐induced reactive oxygen species in the granular sludge than in the flocculent sludge. The granular sludge exhibited richer microbial communities than the flocculent sludge after AZM exposure to the phylum Proteobacteria and Bacteroidetes. CONCLUSION: At high AZM concentration, anaerobic granular sludge was superior to flocculent sludge in COD removal and AZM degradation. This is attributed to less cell death and greater microbial diversity and richness in the granular sludge than in the flocculent sludge following exposure to AZM. Proteobacteria and Bacteroidetes contributed to the resistance to AZM in the granular sludge. © 2018 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• A new metal–organic framework (Eu-MOF- 1) based on Eu(III) and carboxylate linker was synthesized. • Eu-MOF- 1 exhibits an unusual 3D framework based on 1D metal-carboxylate chains. • Eu-MOF- 1 was used as multi-responsive fluorescence sensor for the detection of biomarker 1-naphthol. • Eu-MOF- 1 as a sensor shows high selectivity, sensitivity and remarkable recyclability. A new three-dimensional Eu(III) metal–organic framework Eu(III)-MOF- 1 formulated as [Eu 3 (BDC) 4.5 (H 2 O)(DMF) 2 (H 2 BDC = 1,4-benzenedicarboxylic acid), has been successfully synthesized by solvothermal methods and characterized by structural analyses and luminescence studies. Crystallographic studies reveal that the Eu-MOF- 1 exhibits an unusual 3D framework based on 1D metal-carboxylate chains. Significantly, the luminescence explorations demonstrate that the Eu-MOF- 1 is the first multi-responsive fluorescence sensor for sensing biomarker 1-naphthol (1-N) of carbaryl exposure, Fe3+ ions and MnO 4 − ions with high sensitivity, selectivity and excellent recyclability through luminescence quenching. Moreover, the possible mechanisms of selective detection have been investigated in detail. This material could be a promising luminescent sensor for practical applications. [ABSTRACT FROM AUTHOR]

Carbonate weathering and the CO 2 consumption in karstic area are extensive affected by anthropogenic activities, especially sulfuric and nitric acids usage in the upper-middle reaches of Wujiang River, China. The carbonic acid would be substituted by protons from sulfuric and nitric acids which can be reduce CO 2 absorption. Therefore, The goal of this study was to highlight the impacts of sulfuric and nitric acids on carbonate dissolution and the associated deficit of CO 2 uptaking during carbonate weathering. The hydrochemistries and carbon isotopic signatures of dissolved inorganic carbon from groundwater were measured during the rainy season (July; 41 samples) and post-rainy season (October; 26 samples). Our results show that Ca 2 + and Mg 2 + were the dominant cations (55.87–98.52%), and HCO 3 – was the dominant anion (63.63–92.87%). The combined concentrations of Ca 2 + and Mg 2 + commonly exceeded the equivalent concentration of HCO 3 − , with calculated [Ca 2 + + Mg 2 + ]/[HCO 3 − ] equivalent ratios of 1.09–2.12. The mean measured groundwater δ 13 C DIC value (− 11.38‰) was higher than that expected for carbonate dissolution mediated solely by carbonic acid (− 11.5‰), and the strong positive correlation of these values with [SO 4 2 − + NO 3 − ]/HCO 3 – showed that additional SO 4 2 − and NO 3 − were required to compensate for this cation excess. Nitric and sulfuric acids are, therefore, suggested to have acted as the additional proton-promoted weathering agents of carbonate in the region, alongside carbonic acid. The mean contribution of atmospheric/pedospheric CO 2 to the total aquatic HCO 3 – decreased by 15.67% (rainy season) and 14.17% (post-rainy season) due to the contributions made by these acids. The annual mean deficit of soil CO 2 uptake by carbonate weathering across the study area was 14.92%, which suggests that previous workers may have overestimated the absorption of CO 2 by carbonate weathering in other karstic areas worldwide. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER) in pH-neutral electrolyte is considered more difficult for the additional adsorption and the dissociation process of H 2 O. Herein, by in-suit construction of the heterostructure between MgO and NiCo 2 S 4 on carbon cloth (CC), a novel MgO/NiCo 2 S 4 heterostructure on CC (MgO/NCS-CC) is successfully fabricated. Benefitting from the optimized electronic structure attributed to the construction of hetero-interface, and the intense adsorption of H 2 O on the surface of catalysts owing to the introduction of hydration-effect-promoting (HEP) element Mg, the MgO/NCS-CC exhibits outstanding OER activity with overpotential of 145 mV at the current density of 10 mA·cm−2 in pH-neutral electrolyte and can maintain stability over 40 h. Density-functional theory (DFT) also demonstrates that the MgO/NiCo 2 S 4 heterostructure can effectively adjust the electronic structure and enhance the adsorption of reactant, thus further optimizing Gibbs free energies and improving the activity for OER in pH-neutral electrolyte. [Display omitted] • The hydration-enhancing-effect element Mg effectively enhanced the adsorption of H 2 O on the surface of catalyst. • The unique electronic structure of the heterostructure is the intrinsic reason for the super OER performance. • The catalyst shows outstanding OER performances and excellent stability in pH-neutral condition. • DFT calculation further reveals the change of electronic structure and the enhancement of water adsorption of the catalyst. [ABSTRACT FROM AUTHOR]

The direct alkoxylation of amides has been accomplished via methoxyiminoacyl (MIA)-mediated Pd-catalyzed C-H functionalization. A diverse array of alkylamide substrates is amenable to this protocol, providing γ-C(sp 3 )-alkoxylation of alkylamide derivatives with good to high efficiency. Two aspects of the research were completed to explore the reaction mechanism. On the one hand, the result of the kinetic isotopic effect experiment and control experiment indicated that reductive elimination is a rate-limiting step. On the other hand, density functional theory calculations demonstrated that a concerted Sn2 reductive elimination mechanism pathway is prior. Finally, the MIA group could be efficiently hydrogenated and protected in a one-pot procedure, which provides a short synthetic route to γ-methoxy amino acid derivatives.

Background: The tribe Polyneurini Amyot & Audinet-Serville, 1843 (Hemiptera: Cicadidae: Cicadinae) is a small tribe which includes four genera and 18 species, distributing in eastern Palaearctic and Oriental Regions. Most of them, four genera and 16 species, are known from China., New Information: A remarkable new species of cicada, Polyneuraguoliangi sp. n. (Hemiptera, Cicadidae, Cicadinae), is described and illustrated from Yunnan, southwest China. The diagnostic characters of the new species are compared with allied species or genera., (Cheng-Bin Wang, Peng-Yu Liu.)

The electrocatalytic nitrogen reduction reaction (ECNRR) is a sustainable and environmentally friendly method for NH 3 synthesis under environmental conditions relative to the Haber-Bosch process; however, its low selectivity (Faradaic efficiency (FE)) and low NH 3 yield impede the progress. Herein, benefiting from the application of the interface engineering strategy, a multicomponent TiO 2 /Ag/Cu 7 S 4 @Se-CC heterogeneous electrocatalyst with a unique structure was successfully fabricated, generating a unique sandwich structure by using a Ag layer as an electric bridge intercalated between TiO 2 and Cu 7 S 4 , in which the optimized catalyst can accelerate the electron transfer efficiency. Moreover, through the electronic structure adjustment, an electron-deficient region was constructed, which can inhibit the H 2 adsorption but enhance the N 2 adsorption, thereby improving the selectivity and the catalytic activity. Significantly, the FE and NH 3 yield of TiO 2 /Ag/Cu 7 S 4 @Se-CC reached 51.05 ± 0.16% and 39.16 ± 2.31 μg h -1 cm -2 , in which the FE is among the highest non-precious metal-based NRR electrocatalysts in alkaline electrolytes reported. This study provides insight into the rational design and construction of NRR electrocatalysts for electrocatalytic applications.

Three novel Cd(ii)/Zn(ii) coordination polymers (CPs), namely [Cd(L)(BPDC) 0.5 H 2 O]·0.5H 2 O (1), [Zn 2 (L) 2 (BPDC)]·2H 2 O (2) and [Cd 2 (L)(BTC)H 2 O]·3H 2 O (3) (L = 4-(tetrazol-5-yl)phenyl-4,2':6',4''-terpyridine, H 2 BPDC = 4,4'-biphenyldicarboxylic acid, and H 3 BTC = 1,3,5-benzenetricarboxylic acid), have been successfully synthesized and characterized. CP 1 and CP 2 display new two-dimensional double-layered honeycomb frameworks containing uncoordinated nitrogen atoms from pyridine and tetrazole rings, which can easily form hydrogen bonds with various analytes. CP 3 exhibits a 3D framework also with uncoordinated nitrogen atoms from pyridine and tetrazole rings. The fluorescence explorations indicate that CPs 1-3 exhibit strong blue luminescence and excellent chemical stability under a relatively wide range of pH conditions. It is worth noting that CPs 1-3 can quantitatively detect hippuric acid (HA), which is a metabolite of toluene in human urine, with high selectivity, sensitivity, fast response and relatively low detection limits. Moreover, the sensing mechanism of CPs 1-3 for HA can mainly be ascribed to fluorescence resonance energy transfer (FRET). CPs 1-3 could be ideal candidates as HA sensors in human urine samples for practical applications. Notably, to the best of our knowledge, we report for the first time Cd(ii)/Zn(ii)-based luminescent sensors for detecting HA in simulated urine.

The development and function of a particular organ and the pathogenesis of various diseases remain intimately linked to the features of each cell type in the organ. Conventional messenger RNA- or protein-based methodologies often fail to elucidate the contribution of rare cell types, including some subpopulations of stem cells, short-lived progenitors and circulating tumour cells, thus hampering their applications in studies regarding organ development and diseases. The scRNA-seq technique represents a new approach for determining gene expression variability at the single-cell level. Organoids are new preclinical models that recapitulate complete or partial features of their original organ and are thought to be superior to cell models in mimicking the sophisticated spatiotemporal processes of the development and regeneration and diseases. In this review, we highlight recent advances in the field of scRNA-seq, organoids and their current applications and summarize the advantages of using a combination of scRNA-seq and organoid technology to model diseases and organ development.

A taxonomic review of the genus Trachystolodes Breuning is presented. A new species, Trachystolodes huangjianbini sp. nov., is described from southeast China. Trachystolodes tonkinensis Breuning, 1943 is redescribed and its distribution is discussed. Trachystolodes is redescribed and a key to three known species of Trachystolodes is presented.

The Liulin Spring is one of the ten most famous karst springs in the Shanxi province. The abundant karst groundwater resources support the economic and social development in the Luliang Prefecture. Therefore, the study of evolution and control factors of karst groundwater is of great significance to the sustainable utilization of water resources in the watershed. For revealing the evolution and control factors of karst groundwater in the Liulin Spring area, the main ion components of 29 karst groundwater samples from spring supply area, runoff area, discharge area, and deep buried area were analyzed. The results showed that the temperature and Na + , Ca 2+ , Mg 2+ , Cl - , HCO 3 - , and SO 4 2- concentrations increased continuously along the runoff route, from the recharge area to the runoff area, to the discharge area, and then to the deep burial area. K + , Na + , and Cl - mainly come from salt rock dissolution, and Ca 2+ , Mg 2+ , HCO 3 - , and SO 4 2- mainly come from the dissolution of calcite, dolomite, and gypsum. Because they are controlled by the continuous dissolution of salt rock and gypsum, the concentration of Na + , Cl - , and SO 4 2- in groundwater has increased greatly, with the maximum value being 50 times, 80 times, and 32 times of the minimum value, respectively. Under the influence of dedolomitization, the concentration of Ca 2+ and HCO 3 - in groundwater does not change significantly, the maximum is 2-3 times of the minimum. In the recharge area and runoff area, Na + and Cl - amounts are lower, and Ca 2+ and HCO 3 - are the main cations and anions in the groundwater. However, in the discharge area and deep buried area, Cl - and Na + exceed HCO 3 - , Ca 2+ , and Mg 2+ and become the main anions and cations in the groundwater. The hydrochemical type changes from HCO 3 -Ca·Mg in the supply area to HCO 3 ·SO 4 -Ca·Mg in the runoff area, to HCO 3 ·SO 4 -Ca·Na·Mg in the recharge area, and finally to Cl·HCO 3 -Na·Ca, Cl·HCO 3 -Na, and Cl-Na·Ca in the deep burial area.

Fluorescent substances are used as good tracers in dissolved organic matter (DOM) to identify the source of DOM and its geochemical behavior in a hydrological system. However, there are few studies on the karst aquifer system. Many parameters in karst systems affect the DOM spectral information. A typical karst watershed in Northern China was selected in this research. Excitation-emission matrices (EEMs), parallel factor analysis (PARAFAC), and hydrochemical data were applied to reveal the relationship between the composition and transformation of DOM fluorescent substances in different karst water-bearing spaces. The source of DOM and the effect of water chemistry on DOM transfer were also discussed. The results showed that DOM in exogenous surface water and karst surface water in the Yufu River watershed were mainly composed of tryptophan-like substances, while the DOM in shallow karst water and deep karst water consisted of tryptophan-like and tyrosine-like substances. A comprehensive analysis by fluorescence index (FI), biological index (BIX), and humification index (HIX) displayed that the DOM in shallow and deep karst water resulted from microbial decomposition. In contrast, the DOM in karst surface water and exogenous surface water resulted from land-based input and endogenous microbial decomposition, in which endogenous contributions occupy a large proportion. Due to the chemical parameters of karst water, these three kinds of fluorescent substances extracted by PARAFAC had obviously different characteristics, i.e., ① the tyrosine-like substances had a strong adaptability to Ca 2+ and HCO 3 - , and the proportion of the tyrosine in karst water was relatively large; ② the tryptophan substance followed an opposite trend; and ③ there was a significant positive correlation between fulvic acid and TDS, turbidity, Cl - , and SO 4 2- . Observations of the watershed runoff revealed that the DOM in shallow karst water in the upper reaches came mainly from the soil and microbial degradation. The organic matter underwent a large amount of microbial decomposition and exogenous input when the water was rejuvenated with springs. After infiltration to the deep karst water in the lower reaches, the DOM gradually were converted to low aromatic hydrocarbon organic compounds and decreased macromolecules of DOM. Subsequently, the fluorescence intensity was weakened. The principal component analysis (PCA) extracted three principal components. They were the water mineralization index, soil leaching index, and hydrochemical/biochemical process index. The water mineralization index consists of hydrochemical parameters reflecting the water infiltration, transformation, and flow conditions in the karst system. The soil leaching index contains TOC, NO 3 - , and protein-like indicators relating to the relationship between protein-like substances and soil and natural leaching. The hydrochemical/biochemical process index is composed of Ca 2+ , HCO 3 - , FI, and fulvic acid indicators that illustrate the water chemistry and biochemical processes in the karst water system. In addition, the study also showed that total fluorescence intensity, fulvate-like substances, and protein-like substances can be used as a tracer for rapid seepage, transformation, and aquifer fragility for karst water, respectively. The results of the study are important in understanding the biogeochemical cycle of DOM in the karst water system and also helpful for controlling organic pollution. It also provides a new tool for characterizing the geochemical processes of organic matter in karst system.

An aerobic oxidative cyanation for the synthesis of α-aminonitriles was reported. The formation of C(sp 3 )-CN bonds was achieved under a metal-free condition by utilizing azobis(isobutyronitrile) as a sole organic cyanide source with the combination of pivalic acid and sodium acetate as additives.

The Wujing River, the largest river in Guizhou Province, is one of the most important water resources for social and economical development. Recently, with the fast population proliferation and rapid economic growth, the drainage basin is intensively interfered by anthropogenic activities. The hydrochemistry of surface water was analyzed from the upper-middle reaches of Wujiang River for investigating the hydrochemical characteristics and their main influencing factors. The results showed that the major cations of the four rivers were Ca²⁺ and Mg²⁺, accounting for more than 70%, and the main anions were HCO₃⁻ and SO₄²⁻, occupying more than 85%. The hydrochemical characteristics in the four rivers were found to be of HCO₃-Ca type, and mainly determined by the carbonate rock dissolution, while only a small proportion of them were of HCO₃ · SO₄-Ca type, reflecting the influence of SO₄²⁻ from anthropogenic activities. Compared to hydrochemical data in 1999, there was an obvious increase in cations and anions concentrations, majorly in NO₃⁻, SO2- ion concentrations, which were significantly affected by human activities. The Na⁺, K⁺ , Cl⁻ in the river mainly came from atmospheric precipitation, and Ca²⁺, HCO₃⁻, Mg²⁺, mainly came from carbonate rocks dissolution, while NO₃⁻ and SO₄²⁻ mainly came from human activities. According to principal component analysis and correlation analysis, hydrochemical composition of Liuchong River was affected by human activity, and that in the upstream of Sancha River was controlled by atmospheric precipitation and the dissolution of carbonate rocks, that to the downstream was enhanced by human activities. The main ion of Maotiao River was controlled by atmospheric precipitation and carbonate rocks dissolution, and also affected by human activity. The Nanming River, the Qingshui river's tributary, was mainly affected by human activity, while the middle and lower reaches of Qingshui River were affected by both the atmospheric precipitation and human activity.

Groundwater and surface water from the Upper and Middle Reaches of the Wujiang River were sampled and analyzed for the hydrochemistry and Carbon isotope in DIC. Then hydrochemical characteristics and the main influencing factors were investigated, and the contributions of carbonate dissolution by sulphuric acid to total(Ca2+ + Mg2+) and HCO3 were calculated using the stoichiometry method. The results showed that the advantage cations of groundwater and surface water is Ca2+, which accounted for more than 50% and the advantage anions is HCO3- and SO(4)2-, which accounted for more than 85%. The hydrochemical characteristics of most samples were of Ca-HCO3 type, and a small part of HCO3.SO4-Ca, reflecting a few samples affected by SO(4)2- from human source. The δ13CDIC of groundwater and surface water, varying from -12. 98%o to -6. 36%o with a changeable molar ratio between (Ca2+ + Mg2+) and HCO3- of 1. 11 to 1. 90, indicated that sulfuric acid has an important influence on hydrochemistry and δ3CDIC. The contributions of carbonate dissolution by sulphuric acid to total (Ca2+ + Mg2+) and HCO3 in groundwater ranged from 20. 59% to 92. 87% (average 51. 50%), and from 11. 47% to 86. 69% (average 36. 90%). While the contributions of carbonate dissolution by sulphuric acid to total (Ca2+ + Mg2+) and HCO3- in surface water ranged from 56. 14% to 94. 55% (with an average of 76. 89%), and 39. 02% to 89. 66% (with an average of 64.24%), respectively, demonstrated that sulphuric acid is an important agent of carbon rock weathering. The results of this study have a great significance for the protection and development and utilization of water resources in the Wujiang River basin and for karst carbon cycle research.

Background: Danggui (Radix Angelicae Sinensis) is an herb often used in Traditional Chinese medicine. It is used to promote blood flow and has been used in the treatment of myocardial ischemia-reperfusion injury in animal models. Angiotensin II (Ang II) has been shown to play important roles in mediating cardiovascular diseases, and may cause cardiac hypertrophy and apoptosis. This study aimed to investigate whether Danggui has protective effects on Ang II-induced apoptosis in H9c2 cardiomyoblast cells and study the mechanisms involved., Methods: We evaluated the effect of Danggui on Ang II-induced apoptosis in an in vitro model. H9c2 cardiomyoblast cells were cultured in serum-free medium for 4 hr, then treated with Danggui (50, 100 μg/ml) 1 hr pre- or post-Ang II treatment. After a further 23 hr of culture, cells were harvested for analyses with assays for apoptosis markers and cell signaling pathways., Results: Our results showed that Ang II induced upregulation of pro-apoptotic Bad, instability of the mitochondria membrane potential, cytochrome c release, caspase-9 and caspase-3 activation and cardiomyocyte apoptosis. Pre- or post-treatment with Danggui reversed all of the above Ang II-induced apoptotic effects in H9c2 cells. Furthermore, the JNK (SP600125) inhibitor completely blocked Danggui inhibition of caspase-3 activation in Ang II-treated H9c2 cells., Conclusions: Our results showed that Danggui either pre-treatment or post-treatment highly attenuated the Ang II-induced apoptosis in cardiomyoblast cells. The findings demonstrated that the anti-apoptosis effect of Danggui is mediated by JNK and PI3k inhibitors.

The riverine carbon flux is a critical component of global carbon cycle. Riverine water samples were collected from eleven hydrometric stations in the main stream of Pearl River and its tributaries during April and July, 2012. The samples were analyzed for the space and seasonal distribution characteristics of the riverine suspended substance and carbon compositions. Carbon fluxes and erosion modulus of Pearl River basin were also estimated in Boluo, Shijiao, Gaoyao, namely Dongjiang, Beijiang, Xijiang, in these two hydrological seasons. The results showed that the total suspended substance (TSS) and organic carbon, including total particulate organic carbon (POC) and dissolved organic carbon (DOC) have higher concentration in the high-water season than that in the normal-water season. Dissolved inorganic carbon (DIC) has an overwhelming concentration compared to other carbon compositions in Pearl River basin. The DIC concentration shows an order of Xijiang, Beijiang and Dongjiang from high to low. The percentage of allogenic POC in Xijiang, Beijiang and Dongjiang are 78%, 72%, 26%, respectively, and C3 plants are the main sources of allogenic POC in those three tributaries. The transported fluxes of TSS, total carbon (TC), POC, particulate inorganic carbon (PIC), DOC, DIC, total particulate carbon (TPC) and total organic carbon (TOC) are 134 x 10(12),12.69 x 10(12), 2.50 x 10(12), 1.01 x 10(12), 1.13 x 10(12), 8.05 x 10(12), 3.51 x 10(12) and 3.65 x 10(12) g x a(-1), respectively, and the erosion modulus of those compositions are 309 x 10(6), 28.98 x 10(6), 5.75 x 10(6), 2.27 x 10(6), 2.56 x 10(6), 18.4 x 10(6), 8.02 x 10(6) and 8.31 x 10(6) g x (km2 x a)(-1), respectively. Compared with average values of global large rivers, the erosion modulus of DOC, POC, and TOC in Pearl River basin are higher than the corresponding values.