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Background: The Xpert MTB/RIF assay is an automated molecular test that is designed to simultaneously detect Mycobacterium tuberculosis (MTB) complex and rifampin resistance. However, there are relatively few studies on this method in China. Xpert has been routinely used at Peking University People's Hospital (PKUPH) since November 2016. Thus, the aim of this study was to evaluate the performance of Xpert, and provide a reference and guidance for the detection and diagnosis of TB in non-TB specialized hospitals.Methods: The medical records of inpatients simultaneously tested with Xpert, acid-fast bacilli (AFB) smear microscopy, and interferon-gamma release assay (IGRA, by T-SPOT®.TB) at PKUPH from November 2016 to October 2018 were reviewed. Active TB cases were considered according to a composite reference standard (CRS). Then, the three methods were evaluated and compared.Results: In total, 787 patients simultaneously tested with Xpert, AFB, and IGRA were enrolled; among them 11.3% (89/787) were diagnosed and confirmed active pulmonary TB (PTB, 52 cases), extrapulmonary TB (EPTB, 17 cases), and tuberculous pleurisy (TP, 20 cases). The sensitivity of Xpert in detecting PTB, EPTB, and TP was 88.5, 76.5, and 15.0%, respectively, which was slightly lower than IGRA (96.2, 82.4, and 95.0%, respectively), but higher than AFB (36.5, 11.8, and 0%, respectively); IGRA showed the highest sensitivity, but its specificity (55.9, 67.1, and 45.2%, respectively) was significantly lower than Xpert (99.6, 99.4, and 100%, respectively) and AFB (99.0, 99.4, and 100%, respectively) (P < 0.001). The sensitivity of Xpert in detecting lung tissue, cerebrospinal fluid, lymph nodes, and joint fluid was 100%, followed by sputum (88.5%), alveolar lavage (85.7%), and bronchoscopy secretion (81.2%); the pleural fluid sensitivity was the lowest, only 15.0%. For AFB negative patients, the sensitivity of Xpert in detecting PTB, EPTB, and TP was 84.9, 73.3, and 15.0%, respectively.Conclusions: Xpert showed both high sensitivity and high specificity, and suggested its high value in TB diagnosis; however, the application of pleural fluid is still limited, and should be improved. Owing to the high sensitivity of IGRA, it is recommended for use as a supplementary test, especially for assisting in the diagnosis of TP and EPTB. [ABSTRACT FROM AUTHOR]

Abstract: In order to characterize the recycled lower continental crust (LCC) in the Dabie orogen, 17 Early Cretaceous low-Mg adakitic (LMA) and 9 normal (non-adakitic) granitoids have been investigated for Srph name="sbnd" />Pb isotopes. Combined with literature data, LMA have low ƐNd(t) (−27.8 to −14.7) and 206Pb/204Pb(i) (15.69–17.16) and low to moderately high 87Sr/86Sr(i) (0.7066 to 0.7087) ratios. Normal granitoids yield isotope ratios similar to adakitic rocks, except a few with 87Sr/86Sr (i) up to 0.7105. Dabie LMA define a linear trend parallel to the North Hemisphere Reference Line (NHRL) in a 208Pb/204Pb(i)– 206Pb/204Pb(i) diagram. For a given 206Pb/204Pb(i), the 208Pb/204Pb(i) or ∆8/4 (152–217) of Dabie LMA are close to the majority of UHP gneisses and the Neoproterozoic mafic rocks from the northern margin of the South China Block (SCB), but significantly higher than adakitic rocks from the North China Block (∆8/4<150). Considering the commonly present Neoproterozoic inherited zircons, we suggest that the LMA in the Dabie orogen are derived from a thickened LCC that could be dominantly composed of ancient SCB lower crust. The Srph name="sbnd" />Pb isotopic composition of LMA are similar to those of Post-Collisional Mafic Igneous rocks (PCMI) from the Dabie orogen, but different to exhumed UHP rocks. The Srph name="sbnd" />Pb isotopic system of the mantle source of the PCMI could be enriched in components dominantly from delaminated LCC of the Dabie orogen instead of deeply subducted continental crust, which is in contrast to O- and C-isotope data by [Zhao, Z.F., Zheng, Y.F., Wei, C.S., Wu, Y.B., Chen, F.K., and Jahn, B.M., 2005. Zircon Ulement and C geochemistry of post-collisional mafic–ultramafic rocks from the Dabie orogen in east-central China. Lithos 83(1–2), 1–28; Dai, L.Q., Zhao, Z.F., Zheng, Y.F., Li, Q.L., Yang, Y.H., and Dai, M.N., 2011. Zircon Hf evidence for crust–mantle interaction during continental deep subduction. Earth and Planetary Science Letters 308, 229–244]. Combining the Srph name="sbnd" />Pbce:glyph name="sbnd" />C isotopic data, two types of commonly present magma components have been identified in the PCMI, reflecting crust–mantle interaction during the Triassic subduction and the Early Cretaceous orogen collapse, respectively. [Copyright &y& Elsevier]

Abstract: We present here a combined study of Early Cretaceous granodiorites, granites and mafic rocks from the Bengbu area on south-eastern margin of the North China Craton (NCC), in order to provide insights into the thinning mechanism of lithosphere on the cratonic margins. Zircon U–Pb and Ar–Ar dating reveals an adakitic–basaltic–granitic magma sequence with the adakitic intrusions (granodiorites; 123–115Ma) formed prior to the granites and mafic dykes (both ca.112Ma). The granodiorites are geochemically similar to low-Mg# adakitic rocks and isotopically have enriched Sr–Nd–Hf compositions, low radiogenic Pb (206Pb/204Pbi =16.524–17.017), and mantle-like δ18Ozircon (5.8±0.5‰). They were originated from the thickened lower continental crust (LCC) of the NCC. In contrast, the granites have low Sr/Y (<20), La/YbN, Dy/YbN, and prominent negative Eu anomalies, indicating their origination at the shallow middle-lower crustal levels. The mafic dykes are enriched in LREE relative to HREE, and exhibit negative anomalies of Nb, Ta, Ti and positive anomalies of Pb. They have low Nb/U, Ce/Pb, high La/Nb, Ba/Nb, enriched Sr–Nd isotopic compositions and low radiogenic Pb (206Pb/204Pbi =16.789 to 17.262), indicating LCC materials involved into the mantle sources. Modeling suggests derivation of the mafic dykes from the depleted upper mantle hybridized by 10–15% recycled LCC. The contrasting chemical characteristics of adakitic rocks and granites imply that recycling of the LCC was likely achieved through rapid foundering at 115–112Ma, which resulted in thinning of the overlying crust and hybridization of the underlying mantle with closely coeval generation of granitic and basaltic magmas. Anatexis of the pre-existing thickened LCC at 123–115Ma that attenuated the LCC itself and left the residues denser as a result of felsic (adakitic) melt extraction is proposed to have resulted in gravitational instability and foundering of the lithosphere. Such a temporal sequence of magma generation and processes of lithospheric thinning also occurred on north margin of the NCC and are quite similar to the mountain-root removal beneath the Dabie Orogen in central China. This manifests that previous melting of the LCC is perhaps an important trigger responsible for lithospheric foundering in orogenic belts and cartonic margins, where the lithosphere underwent pre-thickening by continental collisions and had stabilized over a long time. [Copyright &y& Elsevier]

The objective of the present study was to determine the effectiveness of a soluble dietary fiber, NUTRIOSE®, on body weight, body composition, energy intake and hunger in overweight Chinese men. The volunteers were randomized in double-blind fashion to 250 ml fruit juice supplemented with NUTRIOSE® (Test, n = 60) or a maltodextrin (Control, = 60) at a dosage of 17 g twice daily for 12 weeks. Body weight, body composition were performed at 0, 4, 8 and 12 weeks while daily energy intake and hunger were assessed every 3 days. Test subjects had reductions in body weight (1.5 kg, P < 0.001), body mass index (0.5 kg/m2, P < 0.001) and body fat percentage (0.3%, P < 0.001) versus Controls. NUTRIOSE® supplementation resulted in a lower daily energy intake (3,079 kJ/day, P < 0.001) with group differences noted as early as 3 days. Test subjects reported less hunger across the study period versus Controls ( P < 0.01). NUTRIOSE® supplementation for 12 weeks results in body composition improvements and reduces body weight, energy intake and hunger in overweight men. [ABSTRACT FROM AUTHOR]

Abstract: Adakites are commonly associated with porphyry Cu–Au ore deposits worldwide. Two groups of early Cretaceous adakites occur widely in central-eastern China but their association with mineralization contrasts sharply: adakites from the Lower Yangtze River Belt (LYRB) host one of the largest porphyry Cu–Au deposit belts in China, whereas those from the South Tan-Lu Fault (STLF), which is adjacent to the LYRB, are all ore-barren. These adakites, thus, provide a rare opportunity to explore the main factor that controls the genetic links between adakites and Cu–Au mineralization. Here we report new chronological, elemental and Sr–Nd–Pb isotopic data and present a comprehensive geochemical comparison for these two groups of adakites. At a given SiO2, the STLF adakites show lower Al2O3 and higher K2O, K2O/Na2O, MgO, Cr, Ni and Mg# than the LYRB adakites. These systematic differences may indicate a dry basaltic source for the STLF adakites and a water-enriched basaltic source for the LYRB adakites. The STLF adakites have high Sr/Y and (La/Yb)N, which are positively correlated, and low Sr/La and Ce/Pb, while the LYRB adakites show lower (La/Yb)N but higher Sr/Y, Sr/La and Ce/Pb than the STLF adakites. Furthermore, the LYRB adakites are characterized by highly radiogenic Pb isotopic compositions with 206Pb/204Pb(t) up to 18.8, which are clearly distinct from the STLF adakites with low radiogenic Pb (206Pb/204Pb(t)=15.8–16.4). Although the high Mg# of the two groups of adakites suggest reaction with mantle peridotites during magma ascent, the geochemical comparisons indicate that the STLF adakites were derived from partial melting of the delaminated eclogitic lower continental crust, while the LYRB adakites were derived from partial melting of the seawater-altered oceanic crust that was being subducted towards the LYRB during the early Cretaceous. The petrogenetic contrasts between these two groups of high-Mg adakites, therefore, indicate that the large-scale Cu–Au mineralization is associated with oceanic slab melting, not delamination or recycling of the ancient lower continental crust, as previously proposed. [Copyright &y& Elsevier]

Leucogranites have a relatively narrow variation in SiO[sub2] content (70.5%-75.5%). Giving similar SiO[sub2] content, leucogranites have relatively higher Al[sub2]O[sub3] (>13.5%) and lower TFeO + MgO (<2.5%) contents than those of normal granites. These petrochemical characteristics suggest that leucogranites are derived from partial melting at relatively low temperature and are not significantly affected by fractional crystallization. In the present study, we propose that the Al[sub2]O[sub3] vs SiO[sub2] and TFeO + MgO vs SiO[sub2] diagrams can be used to distinguish leucogranites from normal granites. In addition, we report the major element compositions of the Jurassic granitic intrusions from Jingshan-Tushan-Mayishan in the Bengbu area, east-central China. Using the Al[sub2]O[sub3] vs SiO[sub2] and TFeO + MgO vs SiO[sub2] diagrams and the comparison with the High Himalayan leucogranites in mineralogical and petrochemical characteristics, we suggest that the Jingshan-Tushan-Mayishan intrusions belong to a leucogranite belt. Similar to those of the High Himalayan leucogranites, the Bengbu leucogranites have low Mg[sup#] values, indicating that they resulted from low temperature dehydration partial melting of the subducted continental crust of the South China Block at the crustal depth. [ABSTRACT FROM AUTHOR]

Abstract: The late Mesozoic high-Mg adakitic rocks from Eastern and Central China provide important insight into the foundering mechanism of the over-thickened lower continental crust. The Chituling high-Mg adakites (131±3 Ma, SHRIMP zircon U–Pb age) from the eastern margin of the Southern Dabie ultrahigh pressure metamorphic zone, adjacent to the Tan–Lu fault, have high Al2O3 and Sr contents, high Sr/Y, La/Yb, and Mg# (44–63), but low Y and Yb contents. The samples also have moderately enriched 87Sr/86Sr i (0.70691–0.70775), very low ε Nd(T) (−20.7 to −24.9), unradiogenic Pb isotopes, enrichment of large ion lithophile elements, and depletion of high field strength elements. These geochemical features indicate that they did not result from melting of young oceanic crust, assimilation and fractional crystallization, or magma mixing. Instead, they were derived from partial melting of delaminated lower continental crust, with subsequent reaction with surrounding mantle peridotites during ascent to crustal depths. The reactions between the adakitic melt and peridotites also generated the enriched mantle source of the post-collisional basaltic rocks in the Dabie orogen. Distribution of the late Mesozoic high-Mg adakites in eastern and central China generally forms a high-Mg adakite belt along the southern Tan–Lu fault. Therefore, we propose that the large strike-slip motion of the Tan–Lu fault in eastern and central China due to the western subduction of the Pacific plate in the early Cretaceous might trigger the foundering of some fragments of the over-thickened lithosphere near the Tan–Lu fault, which caused mantle upwelling and partial melting of the thickened lower crust in the Dabie orogen and eastern boundary of the North China Craton. This further weakened the gravitationally instable lithosphere, consequently resulting in delamination and foundering of the mountain root underneath the Dabie orogen, which could be an important foundering mechanism of lower continental crust. [Copyright &y& Elsevier]

Abstract: Post-collisional mafic–ultramafic intrusive rocks from the North Dabie zone show evidence for derivation from a mantle source that was overprinted by partial melts derived from subducted crust of the South China Block. All the samples are characterized by enrichment of large ion lithophile elements (LILE, e.g., Ba, Th) and depletion of high field strength elements (HFSE, e.g., Nb, Ti). The Zhujiapu intrusion developed in the North Dabie zone has moderately enriched 87Sr/86Sr i (0.70605–0.70827), negative ε Nd(T) values (−2.3 to −18.8), and unradiogenic Pb isotopes. Such typical “continental” geochemical features do not result from crustal contamination or magma mixing, but reflect the properties of the mantle source. Because the trace element and Sr–Nd isotopic compositions of the post-collisional mafic–ultramafic intrusive rocks from the North Dabie zone are similar to those of the Mesozoic mantle-derived rocks and lower crust granulites and xenoliths from the North China Block, it is unclear whether the “continental” features are due to the contribution of lithospheric mantle and lower crust from the North China Block or deeply subducted materials from the South China Block. However, for a given 206Pb/204Pb i or Δ7/4, the 208Pb/204Pb i or Δ8/4 (159–180) of the post-collisional mafic–ultramafic intrusive rocks from the North Dabie zone is close to the Mesozoic granitoids, eclogites, and gray gneisses from the Dabie–Sulu orogen, but significantly higher than the Mesozoic mantle-derived rocks and lower crust granulites and xenoliths from the North China Block (Δ8/4<160). This indicates that the subducted slabs of the South China Block experienced a higher time-integrated Th/U but similar U/Pb as the deep lithosphere of the North China Block. We therefore propose that the mantle source of the post-collisional mafic–ultramafic intrusive rocks from the Dabie–Sulu orogen result from the depleted upper mantle metasomatised by melts from recycled deeply subducted crust. Due to the continent–continent collision between the South China Block and North China Block in the late Triassic, the lithosphere of the Dabie orogen was over-thickened resulting in eclogitic metamorphism in the mafic lower crust, producing a gravitational instability. The subducted eclogitic lower crust foundered and was recycled into the upper mantle beneath the orogen, resulting in mountain root removal, less mafic composition of unusually evolved continental crust, and upper mantle heterogeneity. [Copyright &y& Elsevier]

Reports on the decoupling of surface and subsurface sutures in the Dabie orogen and a continent-collisional lithospheric-wedging model. Differences of neodymium (Nd) and lead (Pb) isotopic compositions between Mesozoic mafic igneous rocks from the North China Block (NCB) and the South China Block (SCB); Subsurface suture between the NCB and SCB; Southward movement of subsurface suture in the Dabie-Sulu orogen.

The ca. 400-km-long granitoid belt in the South Qinling is believed to be a synorogenic product of the collision between the North and South China Blocks along the Qinling-Dabie orogenic belt in central China. Single and multigrain zircon U-Pb dating of six of these granitoid bodies indicate that the granitoids were formed between 220 plusmn; 1 and 205 ± 1 Ma, supporting the idea that the collision between the North and South China Blocks happened in the Triassic. The formation of these synorogenic granitoids in the South Qinling is similar in time but slightly later than the rapid exhumation of the ultrahigh-pressure metamorphic rocks and their country rocks in the eastern part of the Qinling-Dabie orogen, suggesting a close relationship between the rapid exhumation of the ultrahighpressure metamorphic rocks in the Dabie Mountains and the formation of the South Qinling granitoids. According to regional geology, the breakoff of a subducted slab, if there was any, should have occurred at a shallower depth in the South Qinling compared with that in the Dabie Mountains and Sulu terrane. This shallow breakoff is likely to have disturbed the asthenosphere seriously, leading to the melting of the overlaying lithosphere as well as the formation of the granitoid belt. [ABSTRACT FROM AUTHOR]

Focuses on the lithosphere delamination of the Dabie Sulu orogen in China. Formation of syncollisional granites; Geological relationship between the mafic-ultramafic intrusions and granites; Dynamic causes of the mantle upwelling and underplating.

Examines the uranium-lead isotope composition of rutile, omphacite and garnets in the eclogite in China. Determination of the cooling ages of minerals in ultrahigh-pressure metamorphic rocks; Performance of magnetic and heavy liquid separations; Completion of the chemical and mass-spectrometric analyses.

Examines the characteristics of pyroxenite-gabbro intrusions in the Dabie Mountains in China. Geology of the Dabie Mountains; Isochron age of the intrusions; Mechanics of development of syncollisional granites.

Describes a middle Silurian to early Devonian magmatic arc in the Qinling Mountains of central China. Inference on the causes of the termination of magmatic activities; Implications of whole rock isochron ages.

Soybean is a globally important legume crop that provides a primary source of high-quality vegetable protein and oil. Seed protein and oil content are two valuable quality traits controlled by multiple genes in soybean. In this study, the restricted two-stage multi-locus genome-wide association analysis (RTM-GWAS) procedure was performed to dissect the genetic architecture of seed protein and oil content in a diverse panel of 279 soybean accessions from the Yangtze and Huaihe River Valleys in China. We identified 26 quantitative trait loci (QTLs) for seed protein content and 23 for seed oil content, including five associated with both traits. Among these, 39 QTLs corresponded to previously reported QTLs, whereas 10 loci were novel. As reported previously, the QTL on chromosome 20 was associated with both seed protein and oil content. This QTL exhibited opposing effects on these traits and contributed the most to phenotype variation. From the detected QTLs, 55 and 51 candidate genes were identified for seed protein and oil content, respectively. Among these genes, eight may be promising candidate genes for improving soybean nutritional quality. These results will facilitate marker-assisted selective breeding for soybean protein and oil content traits. [ABSTRACT FROM AUTHOR]

Abstract: The petrogenesis of Early Cretaceous adakitic intrusions in the Lower Yangtze River belt (LYRB), central-eastern China, and their genetic association with Cu–Au mineralization have recently been debated. This study presented integrated in-situ zircon U–Pb–Hf–O isotopic and trace elemental data for the LYRB adakites, and a comparison with ore-barren adakites from the south Tan-Lu fault (STLF) adjacent to the LYRB. Magmatic zircons from these two series of intrusions have U–Pb ages of 145–132Ma and 136–132Ma respectively. The STLF zircons have δ18O ranging from 5.6 to 6.7‰ and εHf(t) from −28.8 to −16.4, plotted within the range of global lower crustal metabasaltic xenoliths, consistent with low-radiogenic Pb of the host adakitic rocks. In contrast, both Hf and O isotopic compositions of zircons from the LYRB are greatly variable with heavier δ18O (4.7 to 9.6‰) and higher εHf(t) values (−25.5 to +2.0) compared with the STLF series. The co-variations of Hf–O isotopes in the LYRB series reflect source heterogeneity as a result of mixing of basaltic oceanic crust with sediments (10–20%), consistent with high-radiogenic Pb and enriched Sr–Nd isotopic compositions of the host adakites. The high La, U and low Ti concentrations in the LYRB zircons also imply a volatile (perhaps, CO3 2−-rich, carbonatite-like) source. Combined with whole-rock geochemical data, the new results further suggest contrasting origins of the LYRB and STLF adakites from subducted oceanic crust and foundering lower continental crust, respectively. The LYRB zircons have much higher ratios of Ce4+/Ce3+ (avg.417) and Eu/Eu* (avg. 0.67) than the STLF zircons (avg. 84 and 0.44). This difference confirms that the ore-bearing adakitic magmas are more oxidized relative to the ore-barren ones. There is roughly a positive correlation between zircon Ce4+/Ce3+ and δ18O in the LYRB series, probably indicating that the elevated fO2 was related to components enriched in heavy oxygen isotopes. A possible candidate is sediments, carried by subducting slabs. The involvement of sediments may significantly promote oxidation of the resulting adakitic melts, a key factor for generation of Cu–Au mineralization, e.g., in the LYRB. This study also indicates that combined in-situ analysis of zircon REEs and δ18O could be a powerful tool to decipher the intrinsic links of fO2 with sediment components in subduction zones. [Copyright &y& Elsevier]

Background: Methicillin-resistant Staphylococcus aureus (MRSA) is a major nosocomial pathogen subdivided into lineages termed sequence types (STs). Since the 1950s, successive waves of STs have appeared and replaced previously dominant lineages. One such event has been occurring in China since 2013, with community-associated (CA-MRSA) strains including ST59 largely replacing the previously dominant healthcare-associated (HA-MRSA) ST239. We previously showed that ST59 isolates tend to have a competitive advantage in growth experiments against ST239. However, the underlying genomic and phenotypic drivers of this replacement event are unclear. Methods: Here, we investigated the replacement of ST239 using whole-genome sequencing data from 204 ST239 and ST59 isolates collected in Chinese hospitals between 1994 and 2016. We reconstructed the evolutionary history of each ST and considered two non-mutually exclusive hypotheses for ST59 replacing ST239: antimicrobial resistance (AMR) profile and/or ability to colonise and persist in the environment through biofilm formation. We also investigated the differences in cytolytic activity, linked to higher virulence, between STs. We performed an association study using the presence and absence of accessory virulence genes. Results: ST59 isolates carried fewer AMR genes than ST239 and showed no evidence of evolving towards higher AMR. Biofilm production was marginally higher in ST59 overall, though this effect was not consistent across sub-lineages so is unlikely to be a sole driver of replacement. Consistent with previous observations of higher virulence in CA-MRSA STs, we observed that ST59 isolates exhibit significantly higher cytolytic activity than ST239 isolates, despite carrying on average fewer putative virulence genes. Our association study identified the chemotaxis inhibitory protein (chp) as a strong candidate for involvement in the increased virulence potential of ST59. We experimentally validated the role of chp in increasing the virulence potential of ST59 by creating Δchp knockout mutants, confirming that ST59 can carry chp without a measurable impact on fitness. Conclusions: Our results suggest that the ongoing replacement of ST239 by ST59 in China is not associated to higher AMR carriage or biofilm production. However, the increase in ST59 prevalence is concerning since it is linked to a higher potential for virulence, aided by the carriage of the chp gene. [ABSTRACT FROM AUTHOR]

Abstract SHRIMP U–Pb dating and laser ablation ICP-MS trace element analyses of zircon from four eclogite samples from the north-western Dabie Mountains, central China, provide evidence for two eclogite facies metamorphic events. Three samples from the Huwan shear zone yield indistinguishable late Carboniferous metamorphic ages of 312 ± 5, 307 ± 4 and 311 ± 17 Ma, with a mean age of 309 ± 3 Ma. One sample from the Hong'an Group, 1 km south of the shear zone yields a late Triassic age of 232 ± 10 Ma, similar to the age of ultra-high pressure (UHP) metamorphism in the east Qinling–Dabie orogenic belt. REE and other trace element compositions of the zircon from two of the Huwan samples indicate metamorphic zircon growth in the presence of garnet but not plagioclase, namely in the eclogite facies, an interpretation supported by the presence of garnet, omphacite and phengite inclusions. Zircon also grew during later retrogression. Zircon cores from the Huwan shear zone have Ordovician to Devonian (440–350 Ma) ages, flat to steep heavy-REE patterns, negative Eu anomalies, and in some cases plagioclase inclusions, indicative of derivation from North China Block igneous and low pressure metamorphic source rocks. Cores from Hong'an Group zircon are Neoproterozoic (780–610 Ma), consistent with derivation from the South China Block. In the western Dabie Mountains, the first stage of the collision between the North and South China Blocks took place in the Carboniferous along a suture north of the Huwan shear zone. The major Triassic continent–continent collision occurred along a suture at the southern boundary of the shear zone. The first collision produced local eclogite facies metamorphism in the Huwan shear zone. The second produced widespread eclogite facies metamorphism throughout the Dabie Mountains–Sulu terrane and a lower grade overprint in the shear zone. [ABSTRACT FROM AUTHOR]

Widespread Cenozoic intraplate basalts from eastern China offer the opportunity to investigate the consequences of interaction between the stagnant Pacific slab and overlying asthenosphere and chemical heterogeneity within this "big mantle wedge". We present and compile a comprehensive study of highly siderophile elements and Mg-Zn isotopes of this magmatic suite (60 samples including nephelinites, basanites, alkali basalts and tholeiites). The large-scale Mg-Zn isotopic anomalies documented in these basalts have been ascribed to mantle hybridization by recycled Mg-carbonates from the stagnant western Pacific plate. Our results reveal that the nephelinites and basanites are characterized by unfractionated platinum-group element (PGE) patterns normalized to primitive upper mantle (PUM) (e.g., Pd N /Ir N normalized to PUM = 1.1 ± 0.8, 1σ), relatively high total PGE contents (e.g., Ir = 0.25 ± 0.14 ppb) and modern mantle-like 187Os/188Os (0.142 ± 0.020). These characteristics are coupled with lighter Mg isotope (δ26Mg = −0.48 ± 0.07‰) and heavier Zn isotope (δ66Zn = +0.46 ± 0.06‰) compositions compared to the mantle values (δ26Mg: −0.25 ± 0.07‰; δ66Zn: +0.18 ± 0.05‰). Together, these data are interpreted to reflect the oxidative breakdown of low proportions of mantle sulfides in the sources of these small-degree melts, likely caused by recycled carbonates, which then release chalcophile-siderophile elements into carbonatitic melts. By contrast, the contemporaneous alkali basalts and tholeiites are characterized by highly fractionated PGE patterns (e.g., Pd N /Ir N = 4.4 ± 3.3; Ir = 0.037 ± 0.027 ppb) and radiogenic 187Os/188Os (0.279 ± 0.115) coupled with less fractionated Mg-Zn isotope compositions (δ26Mg: −0.39 ± 0.05‰; δ66Zn: +0.35 ± 0.03‰). In combination with other isotopic (e.g., Sr-Nd) and chemical (SiO 2 , Ce/Pb, Ba/Th, Fe/Mn) constraints, the alkali basalts and tholeiites were derived from higher degree melting of ancient pyroxenite-bearing mantle in addition to mixing with the aforementioned nephelinitic and basanitic melts. Collectively, we suggest that deep recycled carbonates promoted melting within the "big mantle wedge" leading to the generation of Cenozoic intraplate basalts across eastern China and the "redox freezing of carbonates" may cause the oxidation of Fe0 and S2-. This process may provide an important mechanism to oxidize mantle sulfides and transfer precious metals from deep mantle to crust. [ABSTRACT FROM AUTHOR]

We present high-precision Ca isotopic data for 21 Cenozoic basaltic lavas from eastern China to evaluate the potential of Ca isotopes as a tool to trace the recycling of surface carbonates. These samples were derived from a variety of peridotite to pyroxenite mantle sources hybridized by different slab-derived agents. The δ44/42Ca of eastern China Cenozoic basaltic lavas ranges from 0.24 ± 0.03‰ (2SE, if not specified) to 0.39 ± 0.03‰, with an average of 0.31 ± 0.09‰ (2SD, N = 21), systematically lower than mid-ocean ridge basalts (MORB, 0.39 ± 0.07‰, 2SD, N = 30). No convincing correlation has been observed with δ26Mg and δ66Zn, indicating that metasomatism by recycled carbonates may not always yield Ca isotopically distinct mantle sources. δ44/42Ca shows correlations with parameters reflecting degree of partial melting (e.g., K 2 O, Nb, LREE, U, Th, Rb, and Sr) and residual garnet signature (i.e., (Dy/Yb) N). Nevertheless, modeling results suggest that Ca isotope fractionation during mantle and/or slab melting with the presence of garnet can partially account for the observed variable δ44/42Ca. Recycled carbonates with low δ44/42Ca were likely involved in the origins of the lightest lavas. Particularly, the nephelinitic lightest lavas also have the lowest δ26Mg, Ti/Ti⁎ and Hf/Hf⁎ among all the studied samples, reflecting a role of carbonatitic metasomatism in their sources. This study illustrates that a strongly light Ca isotope anomaly (e.g., δ44/42Ca ∼ 0.24‰) observed in basaltic lavas is likely associated with the recycling of carbonates into the mantle. • Cenozoic basaltic lavas from eastern China have δ44/42Ca variable from a MORB-like value (∼0.39‰) to ∼0.24‰. • The observed δ44/42Ca variation can be partially attributed to isotope fractionation during melting processes. • Involvement of light carbonates in the sources appears to be rather likely for the lightest lavas. [ABSTRACT FROM AUTHOR]

The chemical composition of the upper continental crust (UCC) dramatically changed from predominantly sodic to more potassic during the late Archean (3000–2500 Ma), although how this change occurred remains poorly constrained. The origins of Neoarchean potassic granites may provide clues for this crucial change, as their formation dominated the compositional transition of the UCC. In this study, we conducted high-precision Mg isotopic analyses of Neoarchean potassic granites (2558–2520 Ma) and tonalite–trondhjemite–granodiorites (TTGs; 2595–2574 Ma) from the North China Craton and statistical geochemistry in K 2 O/Na 2 O ratios of global Archean granitoids. Results show that these TTGs, with K 2 O/Na 2 O ratios of ~0.61 and δ26Mg values of −0.39‰ to −0.22‰, were generated from heterogeneous basaltic sources. In contrast, potassic granites yield two distinctive groups of δ26Mg values and can be subdivided into I- and S-types. The I-type granite has mantle-like δ26Mg values of −0.28‰ to −0.22‰ and weak enrichment in K 2 O (K 2 O/Na 2 O = 1.0–1.5), and was likely derived by partial melting of igneous sources. The S-type is characterized by much higher δ26Mg values of +0.60‰ to +0.91‰ and strong K 2 O enrichment (K 2 O/Na 2 O = 1.57–23.26), with geochemical characteristics suggesting derivation by partial melting of sediments. Based on the geochemical characteristics of the S-type potassic granites in this study, we sort the S-type granites out of 4066 Archean felsic igneous rocks worldwide. Their temporal distribution suggests that S-type potassic granites have appeared in the middle Archean (3500–3000 Ma) and became widespread in the late Archean (3000–2500 Ma), but were scarce in the early Archean (4000–3500 Ma). The onset of S-type granites indicates reworking of supracrustal rocks may have started since 3500 Ma. And widespread S-type potassic granites during 3000–2500 Ma play an important role for the high K 2 O/Na 2 O ratio of UCC at the end of Archean. A mass-balance calculation shows that 25.88 wt% I-type, 4.12 wt% S-type potassic granite and 70 wt% TTGs could increase the K 2 O/Na 2 O ratio of the UCC to ~0.83 which is the global average value for felsic rocks at the end-Archean. To increase K 2 O/Na 2 O of the Archean UCC, contributions made by I- and S-type potassic granites could probably reach 3:2, respectively. Consequently, the evolved crustal composition from predominantly sodic to potassic results from the synergy of re-working of igneous (unaltered) and sedimentary (weathered) rocks, by which the former contributed more quantitatively, while the latter contributed more efficiently. • Archean potassic granites hold the key to crustal change from sodic to potassic. • Mg isotopes identify Archean S-type potassic granites in the North China Craton. • The S-type potassic granites begin in the middle and spread in the late Archean. • Remelting of igneous and sedimentary rocks changes upper crustal composition. [ABSTRACT FROM AUTHOR]

Objectives: To evaluate in vitro activity of the novel β-lactamase boronate inhibitor taniborbactam (VNRX-5133) combined with cefepime or meropenem against 500 urinary Gram-negative bacilli.Methods: Cefepime/taniborbactam and 14 comparators were tested by broth microdilution or agar dilution methods. A total of 450 Enterobacteriaceae and 50 Pseudomonas aeruginosa were selected from 2017 to 2019 based on different β-lactamase-producing or resistance phenotypes. For carbapenem-non-susceptible isolates, the modified carbapenem inactivation method (mCIM), EDTA-CIM (eCIM) and amplification of carbapenemase genes were performed. For NDM-producing isolates and those with cefepime/taniborbactam MICs >8 mg/L, the MICs of meropenem/taniborbactam and/or mutations in PBP3 were investigated.Results: Taniborbactam improved cefepime activity with the same efficiency as avibactam improved ceftazidime activity against 66 KPC-2 producers, 30 non-carbapenemase-producing carbapenem-non-susceptible Enterobacteriaceae and 28 meropenem-susceptible P. aeruginosa. However, cefepime/taniborbactam exhibited more potent activity than ceftazidime/avibactam against 56 ESBL-producing, 61 AmpC-producing, 32 ESBL and AmpC co-producing, 87 NDM-producing and 21 MBL-producing Enterobacteriaceae predicted by phenotypic mCIM and eCIM, 82 Enterobacteriaceae that were susceptible to all tested β-lactams and 22 carbapenem-non-susceptible P. aeruginosa. A four-amino acid 'INYR' or 'YRIN' insertion, with or without a one/two-amino acid mutation in PBP3, may have caused cefepime/taniborbactam MICs >8 mg/L among 96.6% (28/29) of the NDM-5-producing Escherichia coli, which accounted for the majority of isolates with cefepime/taniborbactam MICs >8 mg/L (76.1%, 35/46).Conclusions: Taniborbactam's superior breadth of activity, when paired with cefepime or meropenem, suggests these β-lactam/β-lactamase inhibitor combinations could be promising candidates for treating urinary tract infections caused by ESBL and/or AmpC, KPC or NDM-producing Enterobacteriaceae or P. aeruginosa. [ABSTRACT FROM AUTHOR]

Background: Ceftazidime-avibactam was approved in China in 2019 for treating complicated intra-abdominal infections, hospital-acquired pneumonia, ventilator-associated pneumonia, and infections caused by Enterobacterales and Pseudomonas aeruginosa for which treatment options are limited. However, no currently available commercial systems have been approved for antimicrobial susceptibility testing of ceftazidime-avibactam in China. Here, we evaluated the Etest and disk diffusion method for detecting the activity of ceftazidime-avibactam against Enterobacterales and P. aeruginosa in China. Results: In total, 194 Enterobacterales and 77 P. aeruginosa isolates, which were divided into a random selection group (140 Enterobacterales and 46 P. aeruginosa isolates) and stock group (54 Enterobacterales and 31 P. aeruginosa isolates), were assessed by the Etest, disk diffusion and broth microdilution methods. Minimum inhibitory concentrations and zone diameters were interpreted according to the CLSI supplement M100 30th edition. For all 271 tested isolates, no very major errors were found by using Etest, whereas the overall major error rate was 2.0% (4/203). The overall categorical agreement rates of Etest for Enterobacterales and P. aeruginosa were 99.5% (193/194) and 96.1% (74/77), respectively, and the essential agreement rates were 95.9% (186/194) and 94.8% (73/77), respectively. The disk diffusion method showed that the very major error and major error rates were 1.5% (3/204) and 2.5% (5/203), respectively. Overall categorical agreement rates values of the disk diffusion method for Enterobacterales and P. aeruginosa were 98.5% (191/194) and 93.5% (72/77) compared with broth microdilution, respectively. Conclusions: For Enterobacterales and P. aeruginosa, both the Etest and disk diffusion method showed acceptable performance as alternatives to the standard broth microdilution method for clinical treatment interpretation. Application of the disk diffusion method in Enterobacterales was slightly better than that in P. aeruginosa. [ABSTRACT FROM AUTHOR]

Sequence type (ST) 398 is the most prevalent clone of livestock-associated methicillin-resistant Staphylococcus aureus (MRSA). To evaluate the molecular characteristics and phylogeny of Chinese ST398 isolates, 4 MRSA ST398 strains and 4 methicillin-susceptible S. aureus (MSSA) ST398 strains were collected from patients with bacteremia at 6 teaching hospitals in China between 1999 and 2016. Moreover, 689 ST398 genome sequences were downloaded from the GenBank database for comparison. The 4 MRSA ST398 strains were resistant to β-lactam antibiotics, and 2 strains were also resistant to erythromycin. Among the 4 MSSA ST398 strains, 2 strains displayed multidrug resistance (MDR) and were resistant to penicillin, erythromycin, tetracycline, and gentamicin. The accessory genome of MSSA ST398 was more diverse than that of MRSA ST398. All 4 MRSA ST398 strains carried type V staphylococcal cassette chromosome mec elements; however, MSSA ST398 carried more resistance genes than MRSA ST398. These 4 MRSA ST398 strains carried hemolysin, along with virulence genes associated with immune invasion and protease. Phylogenic analysis showed that the 4 MRSA ST398 strains clustered in 1 clade. The global ST398 phylogeny showed that ST398 was divided into an animal clade and a human clade, and the ST398 strains of this study clustered in the human clade. A small number of human strains were also present in the animal clade and vice versa, suggesting transmission of ST398 between animals and humans. In conclusion, livestock-associated MRSA ST398 has caused severe infections in Chinese hospitals, and it should therefore be paid more attention to and monitored. [ABSTRACT FROM AUTHOR]

To explore the mantle source properties and the magmatic evolution process for intraplate basaltic lavas, as well as to investigate the potential of Cr isotopes to trace recycled crustal materials, we present Cr isotope compositions for 72 well-characterized samples of Cenozoic intraplate basaltic lavas from eastern China. These basalts display a resolvable δ53Cr range of −0.24‰ to −0.03‰ (n = 72), comparable to MORB and OIB. With respect to the evolved lavas, their δ53Cr scatter can be interpreted as a result of fractional crystallization of predominant olivine (or/and clinopyroxene) with 1% to 3% spinel from heterogeneous magma sources under different oxygen fugacity conditions. Combined with Sr-Nd-Zn-Fe isotope data, the least evolved basalts with MgO of ∼10% display a large δ53Cr range, indicating the presence of different magma component end-members, including one low-Si and two high-Si components. Two high-Si enriched components have δ53Cr values lower than those of primitive N-MORB and OIB magmas, consistent with their derivations most likely from relatively enriched mantle pyroxenites. Notably, the low-Si nephelinitic component could not be a simple end-member as proposed before. Correlations of δ53Cr with ε Nd(t) -87Sr/86Sr (i) -Fe/Mn-Ti/Ti*-Hf/Hf*-δ66Zn-δ56Fe [Ti/Ti* = Ti N /(Nd N -0.055 × Sm N 0.333 × Gd N 0.722), Hf/Hf* = Hf N /(Sm N × Nd N)0.5. N represents the primitive mantle-normalized values] for nephelinites from both the North China Block and the South China Block suggest mixing between partial melts of carbonated peridotite and pyroxenite sources. The carbonated peridotite derived melt is characterized by depleted Sr Nd isotopes, low Fe/Mn, Ti/Ti* and Hf/Hf* ratios, and heavier than BSE's Cr-Fe-Zn isotope compositions. The highly oxidized environment induced by carbonatization effectively reduces Cr isotope fractionation between melts and residues during partial melting of the carbonated peridotite, resulting in the heavy Cr isotope feature of melts being inherited from the carbonated mantle source, consistent with the heavy Cr isotope compositions of carbonated mantle xenoliths obtained previously. Thus, this work highlights that Cr isotopes might act as a potential tracer for subducted sedimentary carbonates. • This is the first Cr isotope investigation of intraplate basaltic lavas. • Chromium isotopes document limited chromite crystallization. • Chromium isotopes might act as a potential tracer for mantle carbonatization. [ABSTRACT FROM AUTHOR]

Abstract Cycling of elements with multiple valences (e.g., Fe, C, and S) through subduction and magmatism may dictate the redox evolution of the deep mantle and atmosphere. To investigate the potential of Fe isotopes as a tracer of such cycles, here we report Fe isotopic compositions of thirty-seven Cenozoic basalts from eastern China. A nephelinitic melt component with δ 56 Fe up to 0.29 has been identified, which cannot be explained by weathering, alteration, magma differentiation, or chemical diffusion. Its low Fe/Mn ∼58, relatively low TiO 2 and high Na 2 O + K 2 O argue against a significant contribution of pyroxenite melting. Instead, the heavy Fe component requires enhanced isotope fractionation during partial melting of a peridotitic source with Fe3+/ΣFe ≥ 0.15. Low Ba/Th ∼ 50 and depleted 87Sr/86Sr(i) and ε Nd (t) suggest that the source was insignificantly affected by hydrous fluids and recycled terrigenous sediments. The heavy Fe component is known to be unique in its low δ 26 Mg and high δ 66 Zn and indicates hybridization by recycled carbonates. The source Fe3+/ΣFe was most likely enhanced at cost of reduction of recycled carbonates to diamonds in a mantle depth ≥300 km. The origin of the heavy Fe component illustrates a pathway with net transportation of oxidizer back to Earth's surface: CO 2 (in carbonates) → C (as diamond frozen in the deep mantle) + O 2 (ferric Fe being scavenged by melt extraction). Secular cooling of global subduction zones may have stepwisely increased the efficiency of this carbon driven deep oxygen cycle in the past, providing an alternative explanation for the rise of atmospheric O 2. Highlights • Three magma components are identified in Cenozoic basalts from eastern China. • A nephelinitic and heavy Fe component has δ 56 Fe up to 0.29. • Two tholeiitic components have δ 56 Fe typical of MORB and most OIB. • The heavy Fe component from a peridotitic source oxidized by recycled carbonates. • Illustration of a deep oxygen cycle induced by subducted carbonates. [ABSTRACT FROM AUTHOR]

Distinct thermal states of mid-ocean ridges and adjacent transform faults on subducting plates tend to produce distinct magmatic responses on overlying plates. The origins and spatial distribution of the widespread late Mesozoic adakitic rocks in mid-eastern China may provide critical insights into understanding magmatic responses under various thermal states of the underlying Pacific plates. Among them, the intrusive rocks from the Xu-Huai (Xuzhou-Huaibei) region are spatially important but their petrogenesis remains controversial. These intrusions were proposed to be formed by foundering of an 'eclogitic' lower continental crust represented by the mafic xenoliths hosted by these intrusions. By eliminating abundant tiny xenoliths that potentially affect chemical and isotopic compositions of the host rocks, our new data reveal a positive correlation between Sr and Nd isotopic ratios defining two end-members on the EM-I and EM-II arrays respectively, which cannot be explained by a delaminated lower crustal source alone. The radiogenic Pb isotopic ratios of the Xu-Huai intrusions are as high as those of the oceanic crust and marine sediments. Meanwhile, these rocks are sodic with high Na 2 O/K 2 O, and have relatively low (La/Yb) N but high (Dy/Yb) N , Sr/La and Sr/Y, resembling those of oceanic adakites. Given the contemporaneous subducting oceanic ridges under mid-eastern China, the Xu-Huai intrusions were most likely derived from partial melting of a hot subducted oceanic crust that was close to the mid-ocean ridge. Consequently, a sandwich-like distribution pattern of Mesozoic adakitic rocks in mid-eastern China can be recognized, and subduction of a ridge-transform fault-ridge system is proposed to explain this observation. [ABSTRACT FROM AUTHOR]

Iron (Fe) isotope fractionation could occur during crustal melting, which may contribute to the isotopic variations of granites. Our current knowledge on Fe isotope fractionation during crustal melting remains rare. Thirteen leucosomes, 9 melanosomes and 1 amphibolitic schollen in 11 migmatites from the Dabie orogen, Central China were measured to investigate Fe isotope fractionation during crustal anatexis. The melanosomes and amphibolitic schollen yield δ 56 Fe values from 0.018 ± 0.031‰ to 0.152 ± 0.027‰ with an average of 0.106‰. The leucosomes have δ 56 Fe values from 0.107 ± 0.035‰ to 0.512 ± 0.028‰, variably higher than their coexisting melanosomes by 0.00 ~ 0.36‰. The δ 56 Fe of leucosomes and melanosomes, as well as apparent isotope fractionation (Δ 56 Fe L-M ) between them, do not correlate with the abundance of crystalline carbonate, loss on ignition, and Th/U, indicating the insignificant effect of fluid components. High δ 56 Fe values of three leucosomes (≥ 0.34‰), giving large Δ 56 Fe L-M from 0.22 to 0.36‰, were likely produced by feldspar accumulation, evidenced by their high Eu*, low FeOt/Al 2 O 3 and high plagioclase abundance up to 50 vol%. Capture of peritectic amphiboles in another leucosome may explain its low Δ 56 Fe L-M ~ 0‰. After screening out these samples, 7 leucosome – melanosome pairs yield identical Δ 56 Fe L-M averaging 0.093 ± 0.056‰ (2SD, N = 7) within analytical uncertainties. No correlation between Δ 56 Fe L-M and Mg#, FeOt/Al 2 O 3 or TiO 2 /FeOt rules out the possibility that the fractionation observed here is produced by fractional crystallization and/or sub-solidus isotope re-equilibrium between leucosomes and melanosomes. Therefore, we suggest these consistent Δ 56 Fe L-M should record equilibrium Fe isotope fractionation during crustal anatexis producing these migmatites. The leucosomes and melanosomes have comparable Fe 3 + /ΣFe ~ 0.40, and Δ 56 Fe L-M approximates 0.07‰ at Fe 3 + / ΣFe leucosome Fe 3 + / ΣFe menalosome = 1. Fe isotope fractionation during crustal anatexis revealed here thus is not dominantly controlled by distribution of Fe 3 + and Fe 2 + , but by the difference in coordination number of iron between granitic melts and residual mafic minerals. The observation here argues that Fe isotope fractionation during crustal partial melting should also contribute to the previously revealed δ 56 Fe variation in high silica granitic rocks. [ABSTRACT FROM AUTHOR]

Black shales represent one of the main reservoirs of metals released to hydrosphere via chemical weathering and play an important role in geochemical cycling of metals in the ocean. The stable isotope systematics of transitional metals (e.g., Cu and Zn) may be used as a proxy for evaluating their geochemical cycling. To investigate the behaviors of Cu and Zn isotopes during metal enrichment of black shales and the migration during weathering, in this study we reported Cu and Zn concentration and isotope data for unweathered and weathered metalliferous shales and siliceous interbeds from the Maokou Formation in central China. The unweathered shales and cherts have moderately enriched Cu and Zn concentrations with silicate-like δ 65 Cu (+ 0.14 ± 0.09‰, 1σ) but heavy δ 66 Zn (0.51 ± 0.11‰, 1σ). The elevated δ 66 Zn values reflect an important contribution from seawater via sulfide precipitation and/or organic matter (OM) adsorption. The Zn isotopic compositions of these metalliferous shales are different from those of the ‘normal’ shales, highlighting the potential of Zn isotopes as a tracer for metal enrichment in natural systems. The weathered shales and cherts have an extreme δ 65 Cu range from − 6.42‰ to + 19.73‰ and a modest δ 66 Zn range of + 0.25‰ to + 0.78‰. The strongly weathered samples have lower Cu and Zn concentrations and lighter isotopic compositions compared to the weakly weathered samples. The leaching of Cu- and Zn-rich sulfides in shallow depths and their downward transport and refixation by Fe-sulfide account for the Cu and Zn isotope fractionation, with the huge Cu isotope variation generated by multistage redox leaching. In general, δ 66 Zn values of the weathered shales shift towards light values compared to the unweathered protoliths, suggesting that shale weathering releases Zn which is isotopically heavier than igneous rocks and the global riverine average (+ 0.33‰). Our results therefore indicate that Cu isotopes can be extremely fractionated during weathering of Cu-rich shales and both heavy Cu and Zn isotopes are preferentially released into fluids during shale weathering. These results should be considered when evaluating geochemical cycling of Cu and Zn in the modern or past oceans. [ABSTRACT FROM AUTHOR]

The Weirong shale gas field, located within a low-steep structural belt in southern Sichuan Basin, China, is characterized by gentle structural deformation. Production results have shown that inter-well interference, also known as fracture channeling, affects the productivity of shale gas wells by facilitating fluid flow between wells along pre-existing natural fractures. In this study, we used core observational data, scanning electron microscopy, and image logging analysis to determine the type, intensity, occurrence, and genetic mechanism of the natural fractures in the Upper Ordovician Wufeng-Silurian Longmaxi Formation. Attributes such as seismic coherence, AFE (fault-enhanced attribute), dip, and curvature were utilized to predict the macro and meso fault-fractures in the study area. We modeled the micro fault-fractures using the seismic and tracking algorithm to characterize the faults at multiple scales in the Weirong shale gas field, and then completed a comprehensive evaluation of the overall fracture development patterns with respect to the fracture channeling of neighboring shale gas wells. Results indicate that both horizontal and vertical structural fractures have been developed in the shale reservoir of the Wufeng-Longmaxi Formation in the Weirong shale gas field, although the horizontal fractures heavily outnumber the inclined ones. While a few high-conductivity macro and meso fractures display a NE-SW strike, abundant micro-faults have NE-SW and NWW-SEE strikes. Due to the pre-existing basement faults, stress fields and micro-amplitude structure, the NWW-SEE-trending micro fault-fractures are more active than those oriented in the NE-SW direction. Based on field observations, we conclude that regions with well-developed natural fault-fracture networks are more likely to have experienced fracture channeling between or within the platforms of well groups; and the NWW-SEE-trending micro fault-fractures generate more inter-well interference than the NE-SW-trending ones. Predicting the distribution and understanding the origin of the micro fault-fractures make it possible to prevent or mitigate the effects of fracture channeling during the drilling and artificial stimulation of shale gas wells. • Post-stack seismic techniques are used for fracture prediction. • Micro fractures can be accurately characterized by using tracking algorithm. • Natural fault-fracture networks are related to phenomena fracture channeling. • Predicting the micro fractures can prevent the effects of fracture channeling. [ABSTRACT FROM AUTHOR]

Humans are naturally and frequently exposed to a multitude of mycotoxins, but health risk assessments are usually performed on individual mycotoxins, which may underestimate the total risks. In this study, we assessed for the first time the cumulative health risks of concomitant exposure via dietary intake (DI) to multiple mycotoxins, namely deoxynivalenol (DON) and its acetyl derivatives of 3-acetyldeoxynivalenol (3-ADON) and 15-acetyldeoxynivalenol (15-ADON), based on the concentration addition (CA) concept. A cross-sectional study was conducted in seven districts in Shanghai, China with 1269 participants and 330 wheat and maize samples analyzed. After probabilistic analysis using Monte Carlo simulation, the results showed no health risks to the population in Shanghai considering individual mycotoxins. However, if the cumulative health risks were calculated based on the combined consideration of DON with either 3-ADON or 15-ADON or both, the DI values in 95th percentile were up to 1087 ng/kg body weight/day, exceeding the Provisional Maximum Tolerable Daily Intake (PMTDI) of 1000 ng/kg body weight/day and hence representing potential health risks to the population in Shanghai. The integrated study proposed here could be a model strategy for cumulative health risk assessment on the co-occurring hazards in the fields of food safety combined with environmental contaminants. [ABSTRACT FROM AUTHOR]

Abstract: The Late Jurassic Jingshan granite located at the south-eastern margin of the North China Craton contains abundant garnets which can be subdivided into three types based on texture and composition: (i) euhedral garnet in mafic biotite and garnet rich enclave (Grt I), (ii) coarse-grained garnet (Grt II) in the host granite, and (iii) small euhedral garnet in aplite (Grt III). In general, Grt I has higher FeO, CaO and lower MnO contents than Grt II. Grt III has higher Mn, but lower Ca contents than others. Grt I has lower MREE and HREE contents than Grt II. Grt III has prominent and distinctly negative Eu anomaly as well as higher MREE composition compared to the others. Systematic variations in oxygen isotope compositions are observed among the three garnet types, with δ18O values of <3.8‰ in most of Grt I, 3.8–4.7‰ in most Grt II (for inclusion-free garnets), and typically >4.7‰ in Grt III. Some of the Grt II and Grt III display two distinct zonings with cores having similar major and trace element compositions to Grt I. Cathodoluminescence (CL) images revealed that the zircons from different garnet-bearing samples possess fine-scale oscillatory zoned magmatic rims with inherited cores. In situ zircon U–Pb dating and trace element analyses show that the dark-luminescent magmatic rims all have Jurassic concordia ages (∼160Ma) and similar trace element patterns. Most of the inherited cores also display similar Triassic ages of 210–236Ma, which is similar to the ages of ultrahigh pressure (UHP) metamorphic rocks of the Dabie–Sulu orogen (230Ma). In addition, Jurassic concordia ages were also found in a zircon inclusion in Grt I, implying that the Grt I was formed shortly before the main magmatic event. The age data suggest that the three different garnet types may be genetically related and modified by cogenetic magmatic events. Based on the zircon U–Pb ages from different garnet-bearing samples, the major element, trace element, oxygen isotope, and zoning textures of the three kinds of garnet we suggest that Grt I may be peritectic garnet, whereas Grt II and III are probably the results of magmatic dissolution–precipitation processes and re-equilibration of garnets with changing magmatic conditions during melting, differentiation, crystallization, and cooling within the granite. We conclude from the oxygen isotopic character of the garnets and ages of the zircons that the source rocks for the Jingshan granites are from Dabie–Sulu orogen representing the South China Craton. [Copyright &y& Elsevier]

• The proportion of uranium in minerals was notably higher than the adsorbed uranium. • The higher-grade ore had a higher percentage of weak acid-extractable uranium. • Two types of coffinite were found in this area: high-Y and low-Y. • Coffinite closely coexisted with pyrite, altered ilmenite, biotite and clay minerals. • Strongly altered ilmenite was a highly effective aggregating agents for uranium. The Zhiluo Formation in the Tarangaole area is a part of the Dongsheng uranium ore-field in the northeast Ordos Basin, China. Uraniferous sandstones from this formation are examined in this study. The type and mode of occurrence of uranium minerals is investigated in detail using an electron probe, α-track etching, energy spectrum, backscattering, a scanning electron microscope, and an experiment for sequential extraction of uranium. The results show that these uranium minerals are mainly composed of coffinite, a small amount of pitchblende, and some minerals containing titanium and uranium. Coffinite closely coexists with pyrite, altered ilmenite or leucoxene, charcoal, biotite and clay minerals. Some coffinite occurs along mineral edges as burrs or fine columns; it also occurs in biotite cleavage cracks with granulars. In addition, some uranium minerals are also observed within grains. α-Track etching shows that adsorbed uranium is either distributed at the edge of the debris or scattered among the grains. The sequential extraction experiment indicates that the proportion of uranium minerals was significantly greater than that of the adsorbed uranium in the samples, with the latter being largely present in pyrite and organic matter. Residual, oxidizable and weak acid-extractable uranium occur in the deposit. Scan-mapping of uranium and titanium reveales that brannerite is almost nonexistent. Strongly altered ilmenite is considered a highly effective aggregating agent for uranium. A large number of altered minerals, including clays, carbonaceous clastics, biotite, pyrite and ilmenite, are widely developed in the uraniferous sandstone, and play a significant role in the complex process of adsorption–reduction–precipitation of uranium. The discovery of pitchblende and two types of coffinite (high-Y and low-Y) are discussed in context with their symbiotic relationship with the altered minerals. It is suggested that the uraniferous sandstone underwent at least two stages of fluid activity. [ABSTRACT FROM AUTHOR]