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The break-up processes of the northern margin of East Gondwana remain uncertain, especially regarding the Lhasa Terrane. In this paper, we conduct a systematic field geological survey, detrital zircon U Pb dating, and zircon trace element and Hf isotope analyses in the Carboniferous rift basin in the eastern part of the Lhasa Terrane, including the Nuocuo and Laigu Formations, to reconstruct the break-up history of East Gondwana. The overall Carboniferous depositional environment in the eastern part of the Lhasa Terrane changed from near-shore and shallow marine to slope and moderately deep sea facies, reflecting a transgression. The weighted average age of several of the youngest detrital zircons from the Nuocuo Formation is 346.8 ± 6.4 Ma (4 grains), whereas that of the Laigu Formation is 328.7 ± 6.1 Ma (6 grains). The detrital zircon ages in the Carboniferous strata show similar distributions, dominated by zircons from the Indian continent (∼950 Ma), Australian continent (∼1170 Ma), and Lhasa Terrane (∼340 Ma). The paleogeographic position of the Lhasa Terrane was near the Indian and Australian continents during the Carboniferous. The increase of the ∼340 Ma detrital zircon age peak from the Mississippian to the Pennsylvanian demonstrated that the rift basin recorded a Mississippian magmatic event. The ε Hf (t) and oxygen fugacity values of partial zircons of ∼340 Ma are similar to those of zircons from intraplate magmatic rocks, further implying the intracontinental rifting in the Lhasa Terrane. Combined with the previous research on magmatic rocks in East Gondwana, including the Lhasa, South Qiangtang, and Himalayan Terranes, our study on sedimentation found that the Lhasa Terrane was in a passive continental margin rifting context during the Mississippian and the rift gradually expanded to become the Sumdo Paleo-Tethys Ocean basin. [Display omitted] • Carboniferous strata in eastern part of the Lhasa terrane are transgressive sequence. • These strata record the Carboniferous magmatism in the Lhasa terrane. • Carboniferous detrital zircons may mainly originate from intraplate magmatism. • The Lhasa terrane broke up and the Sumdo Paleo-Tethys Ocean opened in ∼340 Ma. [ABSTRACT FROM AUTHOR]

Owing to the impact of the Paleo-, Meso-, and Neo-Tethys Oceans, the Triassic evolution of the Lhasa Terrane is complex and remains debated. The little-known subduction of the oceanic lithosphere of the Sumdo Paleo-Tethys Ocean (SPTO) in the Triassic has especially constrained our understanding of the evolution of the Lhasa Terrane. We investigated the newly identified Triassic granite and metabasalt in the Sumdo area to detail new constraints regarding the Triassic subduction of the SPTO oceanic lithosphere and evolution of the Lhasa Terrane. Zircon LA-ICP-MS U Pb dating for granite and metabasalt yielded crystallization ages of 238.4–236.1 Ma. The granites were strongly peraluminous I-type granites with weakly fractional crystallization. High Nb contents (on average 51.91 ppm), low ε Hf (t) values (−19.7 to +2.8), and ε Nd (t) values (−2.86 to −2.2) suggest that the granites were likely generated by mixing of mantle melts and their induced melts of ancient crustal materials. Metabasalts were analogous to island arc tholeiite with negative Th, Nb, Ti, Zr, and Hf anomalies and positive ε Nd (t) values (+6.1 to +7.1), demonstrating that the magma was likely derived from the partial melting of the depleted mantle metasomatized by subduction fluids. Combined with Triassic magmatism in the Lhasa Terrane, we consider that a divergent double subduction of the SPTO oceanic lithosphere produced the Early Triassic to early Late Triassic magmatism (248–221 Ma) concentrating on both sides of the SPTO suture zone. The Middle Triassic granites and metabasalts in this study were formed in the continental and intra-oceanic arcs, respectively, of the SPTO. Subsequently, closure of the SPTO and collision between the central- and southern Lhasa Terrane might have triggered the subduction of the Indus–Yarlung Tsangbo oceanic lithosphere broadly generating the late Late Triassic magmatism (217–201 Ma) in the Lhasa Terrane. • Middle Triassic I-type granite and tholeiite occurred in the Central Lhasa Terrane. • Mixing of the mantle- and ancient crustal melts produced the I-type granite. • Partial melting of the depleted mantle metasomatized by fluids formed the tholeiite. • They were resulted in the subduction of the Sumdo Paleo-Tethys Oceanic lithosphere. [ABSTRACT FROM AUTHOR]

Obesity is a global public health issue. Obesity-related chronic low-grade inflammation (meta-inflammation) can lead to aberrant adipokine release and promote cardiometabolic diseases and obesity-related tumors. However, the mechanisms involved in the initiation of inflammatory responses in obesity and obesity-related tumors as well as metastasis are not fully understood. In this study, we found that the increased tumor necrosis factor-alpha (TNF-α) in adipocytes promoted the lung metastasis of MC38 colon cancer cells via Fas signaling. The release of TNF-α and interleukin (IL)-6 by Fas signaling in adipocytes was caused by the activation of the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways mediated by the interaction of Fas with Bmx, a non-receptor tyrosine kinase. Moreover, the Fas/Bmx complex is involved in the inflammation of adipocytes via Fas at the Tyr189 site and SH2 domain of Bmx. This is the first study to report the interaction between Fas and Bmx in adipocyte inflammation, which may provide clues for the development of potential new treatment strategies for obesity-related diseases. [ABSTRACT FROM AUTHOR]

• The development of omics technology provides a powerful tool for studying VC. • Multi-omics analysis provides a more comprehensive understanding of the pathophysiological mechanism of VC. • Omics technology promotes the clinical diagnosis of VC. Vascular calcification (VC), the pathological process of hydroxyapatite mineral deposition in the vascular system, is closely associated with aging, atherosclerotic plaque formation, cardiovascular disease (CVD) and diabetes mellitus (DM). Studies have shown that VC is related to cellular phenotypic changes, extracellular vesicles, disordered calcium and phosphate homeostasis, and an imbalance between inducers and inhibitors of VC. Unfortunately, there is currently no effective preventive or targeted treatment for pathologic condition. The rapid evolution of omics technology (genomics, epigenomics, transcriptomics, proteomics and metabolomics) has provided a novel approach for elucidation of pathophysiologic mechanisms in general and those associated with VC specifically. Here, we review articles published over the last twenty years and focus on the current state, challenges, limitations and future of omics in VC research and clinical practice. Highlighting potential targets based on omics technology will improve our understanding of this pathologic condition and assist in the development of potential treatment options for VC related disease. [ABSTRACT FROM AUTHOR]

• The development of omics technology provides a powerful tool for studying VC. • Multi-omics analysis provides a more comprehensive understanding of the pathophysiological mechanism of VC. • Omics technology promotes the clinical diagnosis of VC. Vascular calcification (VC), the pathological process of hydroxyapatite mineral deposition in the vascular system, is closely associated with aging, atherosclerotic plaque formation, cardiovascular disease (CVD) and diabetes mellitus (DM). Studies have shown that VC is related to cellular phenotypic changes, extracellular vesicles, disordered calcium phosphate homeostasis and an imbalance between inducers and inhibitors of VC. Unfortunately, there is currently no effective preventive or targeted treatment for this disorder. Recently, the evolution of omics technology (genomics, epigenomics, transcriptomics, proteomics and metabolomics) has paved the way for elucidation of complex biochemical processes and, as such, may provide new insight on VC. Accordingly, we conducted a review of articles published over the last twenty years and herein focus on current and future potential of omics technology in clarifying mechanisms of this disease process. Identification of new biomarkers will provide additional tools in characterizing this pathology and will further assist in the development of potential therapeutic targets. [ABSTRACT FROM AUTHOR]

In order to accurately analyze the safety management efficiency of China's coal enterprises, based on the panel data of 14 coal listed enterprises in 2012–2018, this paper analyzes the overall technical efficiency (TE), pure technical efficiency (PTE) and scale efficiency (SE) of safety management of sample enterprises by the Data Envelopment Analysis (DEA) model, and builds Tobit model of random panel effect to evaluate the impact of business management and safety investment on safety management efficiency. The results show that: in 2012–2018, the average values of TE, PTE and SE of sample enterprises are respectively 0.674, 0.777 and 0.864; all have great room for improvement. The development of PTE and SE in most sample enterprises is unbalanced; TE of sample enterprises does not significantly improve, and shows a trend of rising-decreasing-rising; safety investment, enterprise scale and labor productivity are significantly positively related to safety management technical efficiency, while safety training person time and employees quality are negatively correlated. This paper identified the positive and negative effects of various influencing factors on the safety management efficiency of coal enterprises, and analyzed the main reasons that hinder the improvement of safety efficiency, and puts forward corresponding countermeasures and suggestions, which are helpful for coal enterprises to effectively improve their safety management efficiency and economic efficiency. [ABSTRACT FROM AUTHOR]

[Display omitted] • The Early Carboniferous clastic sediments in the North Lhasa Terrane was mainly from the Indian continent and partly from the Australian continent. • The North Lhasa Terrane may be located at the northern margin of the Indian- and Australian continent during the Early Carboniferous. • The reduction of Grenvillian detrital zircons in the Yongzhu Formation might be associated with the Early Carboniferous rifting process in the eastern Lhasa Block. The Lhasa Block was located at the northern margin of East Gondwana before it drifted away, but its exact paleogeographic location in the Late Paleozoic remains controversial. The Late Paleozoic strata in the Lhasa Block, especially the Lower Carboniferous, for which the rock assemblage and sedimentary age have been described but the in-depth research on provenance and tectonic environment are still lacking, may provide vital information about its paleogeographic location. This study presents a systematic field geological survey of the Lower Carboniferous Yongzhu Formation, along with U-Pb dating and Hf isotope analysis of detrital zircons. The detrital zircons U-Pb data revealed major age peaks at 530 and 980 Ma as well as several subordinate age peaks at 784, 890, 1160, 1514, 1690, 2480, and 2600 Ma. The Hf isotopes of the detrital zircons showed similarity with zircons from the Indian continent on the age peaks at 980 and 890 Ma and with those from the Australian continent on the age peaks at 1160 and 2600 Ma, which indicates mixed provenance for the Yongzhu Formation. From this study, we infer that the Lhasa Block might have been located at the northern margin of the Indian and Australian continents during the Early Carboniferous. The weaker age peak at 1160 Ma of the Lower Carboniferous compared to the Pre-Carboniferous and Upper Carboniferous-Lower Permian might be related to the opening of the Sumdo Paleo-Tethys Ocean. [ABSTRACT FROM AUTHOR]

In present work, the deformation behavior of AZ31 Mg alloy with surface mechanical attrition treatment (SMAT) had been studied. The microstructure and mechanical properties of AZ31 Mg alloy with SMAT were investigated. The results indicated that a gradient nanostructure could be formed in sample by SMAT, in which the grain size increased gradually from surface to matrix. A depth-dependent gradient microhardness was also formed due to the corresponding gradient microstructure. Yield strength and ultimate tensile strength of AZ31 Mg alloy with SMAT were significantly improved combining with decrease of fracture elongation. The effect of SMAT on anisotropy of mechanical properties of AZ31 alloy had been discussed and analyzed. The plastic anisotropy of the sample increased significantly after SMAT, which was related to the texture variation of rolled sheet and special deformation behavior of gradient nanostructure. Finally, in order to illuminate the difference in deformation behavior between fine and coarse grained microstructure, the in-situ tensile deformation behavior of AZ31 Mg alloy with one-side gradient structure had been studied by SEM. The deformation mechanism of AZ31 Mg alloy with gradient structure had been put forward. [ABSTRACT FROM AUTHOR]

• A fully physical TCAD framework to model the NBTI is validated with differently processes MOSFET measured data. • RD model with ABDWT model for interface trap generation, RDD model for bulk trap generation, ABDWT model for hole trapping is used. • Framework Validation in TCAD in 3D FinFETs and GAA-FETs is in progress. A physics-based framework is incorporated in TCAD to model the primary mechanisms responsible for Negative Bias Temperature Instability (NBTI) in P channel High-K Metal Gate (HKMG) MOSFETs. Three underlying mechanisms are treated including interface trap generation-passivation via a Reaction-Diffusion (RD) model and its charge occupancy via an Activated Barrier Double Well Thermionic (ABDWT) model, hole trapping and de-trapping in pre-existing defects in the gate stack are modeled via an ABDWT model, and bulk trap generation-passivation is modeled via a Reaction-Diffusion-Drift (RDD) model. The framework is used to model measured NBTI time-kinetics for DC stress-recovery and various mixed DC-AC gate pulse segments for planar devices. Furthermore, the same framework is also used to test NBTI behavior in 3D FinFETs. [ABSTRACT FROM AUTHOR]

The Qinling Orogen was a consequence of continental collision of the South China Craton with the North China Craton in the Triassic and caused widespread granitoid magmatism. However, the petrogenesis of these granitoids remains controversial. In this paper, we choose the Baijiazhuang (BJZ) and Lvjing (LJ) plutons in the West Qinling Orogen for a combined study of the zircon U–Pb geochronology, whole-rock major and trace element compositions and Sr–Nd–Hf isotopic characteristics. We obtained zircon crystallization ages of ~ 216 Ma and ~ 212 Ma for the BJZ and the LJ plutons, respectively. The granitoid samples from both plutons have high K 2 O metaluminous to peraluminous compositions. They are enriched in large ion lithophile elements (LILEs), light rare earth elements (LREEs) and depleted in high field-strength elements (HFSEs) with significant negative Eu anomalies. The BJZ samples have initial Sr isotopic ratios of 0.7032 to 0.7078, ε Nd ( t ) of − 10.99 to − 8.54 and ε Hf ( t ) of − 10.22 to − 6.41. The LJ granitoids have initial Sr isotopic ratios of 0.7070 to 0.7080, ε Nd ( t ) of − 5.37 to − 4.58 and ε Hf ( t ) of − 3.64 to − 1.78. The enriched isotopic characteristics of the two plutons are consistent with their source being dominated by ancient continental crust. However, two BJZ samples show depleted Sr isotope compositions, which may infer possible involvement of mantle materials. Mantle-derived melt, which formed from partial melting of mantle wedge peridotite facilitated by dehydration of the subducted/subducting Mianlue ocean crust, provide the required heat for the crustal melting while also contributing to the compositions of these granitoids. That is, the two granitic plutons are magmatic responses to the closure of the Mianlue ocean basin and the continental collision between the Yangtze and South Qinling crustal terranes. [ABSTRACT FROM AUTHOR]

Zinc (Zn) isotope data for mid-ocean ridge basalts (MORB) are scarce. The possible effects of MORB differentiation and mantle compositional heterogeneity on MORB Zn isotope compositions are poorly understood. In this paper, we report Zn isotope data of MORB lavas from the East Pacific Rise (EPR) at 10°30′N, which are understood to have been derived by a similar extent of melting from a compositionally uniform mantle source but manifest significantly varying extents of magma differentiation (MgO = 7.38–1.76 wt%) to demonstrate unequivocal Zn isotope fractionation during MORB differentiation. These lavas have a small δ66Zn (relative to the JMC-Lyon standard) range of 0.21–0.32‰, with an average of 0.26 ± 0.07‰ (2SD, N = 24), overlapping with literature data. However, δ66Zn values show significant correlations with indices of magma differentiation (e.g., MgO and CaO), with the more differentiated samples having isotopically heavier Zn. We can thus conclude that MORB differentiation can lead to ∼0.1‰ δ66Zn elevation, which is similar to that observed in Hawaiian Kilauea Iki lava lake samples. Fractional crystallization of olivine and clinopyroxene at MgO > ∼3.5 wt% and clinopyroxene and Fe–Ti oxides dominated by ilmenite at MgO < ∼3.5 wt% results in the observed Zn isotope fractionation. The δ66Zn values for primitive N-MORB and MORB source mantle are estimated to be ∼0.22‰ and ∼0.17‰, respectively. Furthermore, we observe a positive correlation between δ66Zn and [La/Sm] N in primitive (MgO = 7.58–9.01 wt%) literature MORB, indicating the existence of possible Zn isotope heterogeneity in the oceanic upper mantle. We thus predict heavy Zn isotope enrichment in mantle sources for E-MORB samples with high [La/Sm] N , which requires future testing. [ABSTRACT FROM AUTHOR]

Abstract: Five cadinane sesquiterpenoids, named stereumin A (1), B (2), C (3), D (4) and E (5) were isolated from the CHCl3 extract of the culture broth of the fungal strain CCTCC AF 207024. Based on the sequences at the internal transcribed spacer (ITS) region and partial 28S rDNA, this fungus was identified as a Stereum sp. The structures of the five compounds were elucidated using spectroscopic data from 1D, 2D NMR and HRESIMS experiments, and the structures of 1 and 2 were further confirmed by single-crystal X-ray diffraction analysis. Compounds 1–5 showed nematicidal activities against the nematode Panagrellus redivivus at 400 mg l−1. Among these five compounds, compounds 3 and 4 killed 84.4% and 94.9% of P. redivivus, respectively in 48h. [Copyright &y& Elsevier]

• The sliding mode is fast continuous and nonsingular. • The controller reduces the chattering and renders high-precision performance. • The corresponding parameters are easy to adjust. • The conservativeness of the proposed controller is reduced. • The stability and robustness have been verified by the simulation and experiments. In this paper, a fast terminal sliding mode controller is designed for an active suspension gravity compensation system with unknown bounds of uncertainties and disturbances. A robust finite-time convergence estimator is used to estimate the velocity and the disturbances. The estimator can guarantee that the speed of the estimation errors converge faster than the displacement tracking errors by regulating its gains. The corresponding stability and robustness of the closed-loop system are proved. In particular, the proposed control scheme can reduce the chattering effectively and render the high-precision tracking performance that have been verified by the simulation and experiments. [ABSTRACT FROM AUTHOR]

Water vapor is the most variable constituent in the atmosphere and plays an important role in climate studies, mesoscale meteorology modeling and numerical weather forecasting. Being able to penetrate clouds, interferometric synthetic aperture radar (InSAR) shows great potential in atmospheric water vapor mapping. But InSAR can only measure differential water vapor between two acquisitions. In this paper, we formulate a general framework by constructing the Gauss-Markov model and developing the estimation method to retrieve the non-differential water vapor from Small BAseline Subset InSAR (SBAS-InSAR). To address the rank-deficiency in the Gauss-Markov model, we propose a new constraint, i.e., the temporal mean of water vapor being invariant. Simulated and real data experiments are conducted to validate the effectiveness of the framework and the advantages of the proposed constraint. The results show that the new constraint can offer an estimation more robust than the two traditional ones, i.e., the temporal mean of water vapor being zero and single or multiple epoch water vapor referencing. In addition, we found that there exists a constant bias, which equals to the temporal mean of water vapors, between the solutions under the new constraint and that under the constraint of the temporal mean of water vapor being zero. Finally, the possible methods to evaluate the temporal mean of water vapor are discussed. • Formulating a general framework and developing the estimation method to retrieve the non-differential PWV from TS-InSAR. • Proposing a new constraint to address the rank-deficiency in Gauss-Markov model. • Funding a constant bias between the solutions under the new constraint and that under one of the existing constraints. • Proving the equivalency between the new method and the rule of minimum-norm least-squares. [ABSTRACT FROM AUTHOR]

Nanocrystalline surface layers and gradient nanostructures are produced in AZ31 Mg alloy through surface mechanical attrition treatment (SMAT). The grain sizes in the surface layer of the alloy are significantly refined to a nanoscale after SMAT. A gradient nanostructure is formed in which the grain size increases gradually from surface to matrix. The microhardness of the surface layer and the tensile strength of the alloy are significantly improved, but with a certain loss of fracture elongation. SEM photographs of tensile fracture of samples after SMAT show that the fractures of the GNS layer are brittle fractures with poor toughness, while the plasticity of the matrix is better, and the fractures exhibit typical ductile features. To investigate the effect of SMAT on the textural evolution of AZ31 Mg alloy, electron backscatter diffraction is used to analyze the as-received sample and samples after SMAT. The non-basal plane orientation is increased and the basal texture is significantly weakened in the fine-grained layer after SMAT. The weakening of the basal texture reduces the anisotropy of the mechanical properties of Mg alloys, which is beneficial for their industrial application. • The texture gradient of gradient nanostructured AZ31 magnesium was found by electron backscatter diffraction. • The grain refinement mechanism of gradient nanostructure AZ31 magnesium alloy was obtained. • The microstructural evolution of gradient nanostructured AZ31 magnesium alloy was displayed. [ABSTRACT FROM AUTHOR]

• HPV16 infection is the most prevalent in Tianjin which is tightly relevant to cervical cancer progression. • E-p variant is the most prevalent type followed by As variant in Tianjin urban healthy women screening. • As variant appears higher carcinogenic potential than E-p, and is positively related to the severity of cervical lesions. • E-G350 was only detected in HSIL and cervical cancer, indicating E-G350 is possibly related to elevated risk of lesions. The aim of this study is to investigate distribution of human papillomavirus (HPV) 16 variants in screening healthy women and the potential association between HPV 16 variants and progression of cervical lesions. For this study a total of 2000 healthy women in Tianjin urban area and 212 patients who were HPV 16 positive and underwent colposcopy were analyzed for HPV 16 variants by pyrosequencing. The results show that the HPV 16 was the most prevalent genotype in Tianjin healthy women and five HPV 16 variant types were detected. The HPV 16 variants were determined by sequencing parital E6 region and the detected variants were European prototype E-T350 (E-p), E-G350, E-C109 G, Asian (As) and Asian-American (AA), among which the E-p variant was the most prevalent (82.76%) followed by As variant. Interestingly, in patients with suspected cervical lesions the most prevalent variant was As variant (54.9%) by increasing significance with severity of cervical diseases (OR 4.337; 95% CI 1.248–15.067; P = 0.021), and followed by HPV 16 E-p variant while E-G350 variant only appeared in HSIL and cervical cancer. Our results show that HPV 16 E-p variant was more prevalent than As in Tianjin healthy screening women while As variant was the most frequently type in HSIL and cervical cancer. It is suggested that the mutation of HPV 16 Asian variants, comparing with HPV 16 E-p variants, might contribute to the transformation from HPV 16 persistent infection to cervical cancer. [ABSTRACT FROM AUTHOR]

Abstract The Laoshan granite is an example of the widespread intraplate granitoids of early Cretaceous age in eastern continental China. The petrogenesis of these granitoids remains in dispute and we choose the Laoshan granite as the representative case to study these granitoids. Zircons from the Laoshan granite give a crystallization age of ~120 Ma, which is consistent with the emplacement age of ~ 126 Ma given by the bulk-rock Rb-Sr isochron. Representative samples from the granite show a large range of major element compositional variation (e.g., SiO 2 /MgO = 64 to 1937), reflecting a varying degree of fractional crystallization of plagioclase, alkali feldspar, amphibole, biotite and accessory phases as observed. The samples are enriched in light rare earth elements, Rb, Th and U, but depleted in Ba and Sr with negative Eu anomalies. The high 87Sr/86Sr (0.7083 to 1.2265) is largely caused by variably high Rb/Sr (~0.31 to 91 with an average of ~13) due to feldspar fractionation. The low ƐNd (t) (−13.8 to −19.5), ε Hf (t) (−14.6 to −24.4), and (206Pb/204Pb) i (16.244 to 17.304) are consistent with significant contributions of the lower continental crust to magmas parental to the Laoshan granite. The origin of the parental magmas is best understood as resulting from anatexis of the lower crust (~20% − 25% partial melting of the mafic granulite) triggered by and mixed with the underplating and intruding basaltic magmas. The basaltic magmas were likely derived from melting of the thinning lithosphere being transformed into the asthenosphere as the result of "basal hydration weakening" with the water ultimately coming from dehydration of the stagnant paleo-Pacific slab in the mantle transition zone. Highlights • The Laoshan granite resulted from fractional crystallization of the parental magma. • Anatexis of the LCC heated by and mixed with basic magma formed the parental magma. • The basal hydration weakening caused the lithosphere thinning with basic magmatism. [ABSTRACT FROM AUTHOR]

Redox-driven copper (Cu) isotope fractionation has been widely observed in low-temperature weathering and hydrothermal processes. However, how Cu isotopes may fractionate during magmatic processes remain unknown. To address this issue, we studied MORB samples from the East Pacific Rise (EPR) at 10°30′N to explore the Cu isotope behavior during magma differentiation. These samples are globally ideal because they are generated from a uniformly depleted sub-ridge mantle source but have experienced varying extents of fractional crystallization and sulfide segregation with large variations of MgO (1.76–7.38 wt%) and Cu (16.0–75.2 μg/g). Lavas with MgO ≥ 4.9 wt% involving olivine, clinopyroxene and plagioclase as the major liquidus minerals show homogeneous δ65Cu of 0.05 ± 0.03‰, suggesting little Cu isotope fractionation at this stage of magma differentiation. However, after Fe-Ti oxides appear on the liquidus, melt δ65Cu values first decrease rapidly to –0.41‰ at MgO of 3.9 wt% and then increase with the most evolved sample having δ65Cu of 0.08‰. Such a significant Cu isotope fractionation during magma differentiation has never been reported before. We suggest the large Cu isotope variation at MgO < 4.9 wt% reflect a redox change of MORB melt resulting from fractional crystallization of Fe-Ti oxides. The crystallization of ilmenite (Fe2+TiO 3), which is the first Fe-Ti oxide phase during MORB differentiation, causes a sudden increase of Fe3+/∑Fe in the residual melt and drives the redox reaction Fe3+ + Cu1+ → Fe2+ + Cu2+. As a result, sulfides segregated from the MORB melts have high Cu2+ content and heavy Cu isotope compositions with Δ65Cu Sulfide-Silicate melt > 0 because of the preferential bonding of heavy Cu isotopes (65Cu vs. 63Cu) with Cu2+, whose fractionation rapidly decreases δ65Cu of the residual melts. The increase of Fe3+/∑Fe will quickly drive the melt to be saturated in titanomagnetite (magnetite-Ulvöspinel solid solutions), whose crystallization decreases melt Fe3+/∑Fe and drives the redox reaction Fe2+ + Cu2+ → Fe3+ + Cu1+. As a result, the segregated sulfides after titanomagnetite saturation have decreasing Cu2+ content. These sulfides are also predicted to have low Ni content and exhibit Δ65Cu Sulfide-Silicate melt < 0, whose segregation raises δ65Cu in the residual melts. Therefore, we suggest a significant influence of redox states of Cu and abundance of Ni in the segregated sulfides on the Cu isotope fractionation during MORB differentiation. During mantle melting for MORB at ΔFMQ < 0, Cu isotope fractionation between melt and mantle sulfide is inferred to be limited, and the upper mantle has primitive MORB-like δ65Cu of 0.06 ± 0.05‰. [ABSTRACT FROM AUTHOR]

This paper proposes an incremental scheme to identify the neurons in electronic microscope image. It first computes the probability of each pixel being cell membrane and then determines the image areas of the neurons. Our contributions also include novel combined multi-scale image features that are computationally efficient and provide strong discrimination ability for differentiating membrane pixels from other pixels. Experiment results show that the proposed system offers much higher speed than the compared state-of-the-art methods while produces comparably high accuracy. [ABSTRACT FROM AUTHOR]

• New Sr-Nd-Hf isotopic data on MORB lavas from OH-1 and OH-3 segments at the Mid-Atlantic Ridge 33–35°N. • Three mantle components are identified in the mantle source of these MAR lavas. • A Sr-Nd-Hf isotopic view on the origin of geological differences in OH-1 and OH-3 segments. We present new Sr-Nd-Hf isotopic data on mid-ocean ridge basalts from two ridge segments (OH-1, OH-3) between the Oceanographer and Hayes fracture zones at the Mid-Atlantic Ridge 33–35°N to constrain the nature and origin of upper mantle heterogeneity beneath the Mid-Atlantic Ridge. Together with the major and trace elements data (Niu et al., 2001), the new Sr-Nd-Hf isotopic data illustrate that the mantle sources of these lavas comprise three components, i.e., a depleted mantle with high radiogenic Hf isotopic compositions (ADM), an incompatible elemental enriched component with radiogenic Sr and un-radiogenic Nd-Hf isotopic compositions (E-type I), and an incompatible element depleted component with variably enriched Sr-Nd-Hf isotope compositions (i.e., E-type II). The ADM and E-type I components may be understood as representing ancient mantle melting residues and metasomatic veins developed at the base of the thickening oceanic lithosphere, respectively. The unique E-type II component is best explained as recent mantle melting residues of a geochemically enriched mantle, probably associated with the Azores mantle plume to the north. Taking together, we interpret the E-MORB dominated OH-1 lavas as resulting from a relatively higher degree melting of a mantle source composed of ADM matrix and E-type I material, whereas the N-MORB dominated OH-3 lavas resulting from lower degree melting of the mantle source primarily comprising ADM and E-type II components. Such a petrological and geochemical understanding explains the contrast in crustal thickness, ridge morphology and tomography, and mantle Bouguer anomalies between the two ridge segments. [ABSTRACT FROM AUTHOR]

Studies of mid-ocean ridge basalts (MORB) have revealed a heterogeneous asthenospheric mantle in chemical elements and radiogenic isotopes. Here we report that MORB mantle is also heterogeneous in Fe isotopes through studying the glass samples from seamounts flanking the northern East Pacific Rise between 5° and 15°N. These samples show large Fe isotope variation with δ56Fe values (+0.03‰ to +0.36‰) exceeding the known range of MORB (+0.05‰ to +0.17‰). Such highly varied δ56Fe values cannot be well explained by seafloor alteration, fractional crystallization or partial melting processes, but instead require a source mantle significantly heterogeneous in Fe isotope compositions. Importantly, the δ56Fe values of these basalts correlate significantly with major and trace elements and Sr-Nd-Pb-Hf radiogenic isotopes, reflecting melting-induced mixing of a two-component mantle with the enriched component having heavy Fe isotope compositions dispersed as physically distinct domains in the depleted mantle matrix. The major and trace element characteristics of the enriched mantle component, as inferred from these basalts, are consistent with a low-degree melting origin. Such low-degree melts with heavy Fe isotope compositions most likely formed at sites such as the lithosphere-asthenosphere boundary beneath ocean basins, which can metasomatize the overlying oceanic lithosphere by crystallizing dikes/veins of garnet pyroxenite lithologies. Recycling of these dikes/veins with isotopically heavier Fe can readily contribute to the Fe isotope heterogeneity in the MORB mantle. However, the extremely high primitive δ56Fe values of the two alkali basalts (up to 0.34‰) require an enriched source component with unusually high δ56Fe values. We suggest that partial melts from the recycled dikes/veins of garnet pyroxenite lithologies can react with the ambient peridotitic mantle and generate a secondary garnet pyroxenite with heavier Fe isotope compositions than, but similar radiogenic isotope compositions as its precursor. Melting-induced mixing between these garnet pyroxenites (recycled and newly formed) and depleted mantle matrix can readily explain the compositional variations in elements, radiogenic isotopes and Fe isotopes observed in these seamount lavas. These new data and correlated variations offer a new dimension for understanding the origin of mantle chemical and isotopic heterogeneity in the context of chemical differentiation of the Earth. [ABSTRACT FROM AUTHOR]

Whether the Earth's mantle has a chondritic δ56Fe (deviation in 56Fe/54Fe from the IRMM-014 standard in parts per thousand) value or not remains under debate. The current view is that the observed average δ56Fe of mid-ocean ridge basalts (MORB) cannot be explained by partial melting of mantle source with chondritic value alone. Here, we report Fe isotope compositions on 29 MORB glasses sampled along a flowline traverse across the East Pacific Rise (EPR) axis at 10°30′N. These glasses show large MgO variation (1.8–7.4 wt.%) that forms a compositional continuum resulting from varying extent of fractional crystallization, which is accompanied by systematic Fe isotopic variation. Fractional crystallization modeling suggests that early crystallization of olivine, pyroxene and plagioclase gives rise to an iron enrichment trend and an increase in δ56Fe. Once Fe-Ti oxides appear on the liquidus and begin to crystallize, the FeOt and TiO 2 contents of the residual melt decrease rapidly, which lead to a slight decrease in δ56Fe. These observations indicate that significant Fe isotope fractionation can indeed take place during MORB melt evolution. Hence, δ56Fe values of variably evolved MORB melts do not represent those of primary MORB melts and thus cannot be used to infer mantle source Fe isotope compositions. Importantly, δ56Fe values of primary MORB melts after correction for the effect of fractional crystallization can be well reproduced by mantle melting. Therefore, our study supports the idea that the Fe isotope composition of the accessible Earth is close to be chondritic. We note that conclusion would assume that the core, which takes up ∼90% of the Earth's Fe, must have a chondritic Fe isotope composition. [ABSTRACT FROM AUTHOR]

Spatial heterogeneity in the atmospheric refractive index causes variations in spaceborne interferometric synthetic aperture radar (InSAR) observations. The neutral atmospheric delay (i.e., the tropospheric delay) on one hand, can introduce large errors in the InSAR-derived displacements associated with earthquakes, volcanic activity, glacier motions, underground resource extraction, and many other crustal deformation phenomena. On the other hand, the tropospheric delay can be used to infer high-resolution maps of the non-differential atmospheric water vapor. Time-series InSAR techniques aim to measure geodetic and/or geophysical parameters of interest by integrating time series of SAR images or interferograms using statistical or adjustment methods, through the reduction of error sources (e.g., atmospheric delays, decorrelation noises). This contribution is intended to systematically review the properties, mitigation, and estimation of the atmospheric delays in TS-InSAR for better monitoring ground deformation. We first review the present TS-InSAR techniques and introduce the spatio-temporal characteristics of the neutral atmospheric delays observed in TS-InSAR. We then present the estimates and integration of atmospheric stochastic models for TS-InSAR applications. We construct, analyze, and illustrate a high-resolution non-differential atmospheric water vapor model from TS-InSAR observations. Finally, we present a discussion and outlook for the TS-InSAR atmospheric delay models and estimation efforts. [ABSTRACT FROM AUTHOR]

Abstract We sampled 22 Mesozoic dykes in eastern continental China and carried out a detailed study on these samples, including K–Ar and zircon U–Pb geochronology, and elemental and Sr-Nd-Pb-Hf isotope geochemistry. Their K–Ar and zircon ages of 130-110 Ma are broadly consistent with the timing of the lithosphere thinning and the emplacement ages of widespread granitoids in the vast region, explicitly pointing to a common cause in space and time. The dykes represent evolved alkaline basaltic melts intruding the Mesozoic granitoids. Their rare earth element (REE) and multi-element patterns differ from the present-day ocean island basalts (OIB), but show strong arc-like signatures (e.g., enrichment in Rb and Pb and depletion in Nb, Ta and Ti). They show high (87Sr/86Sr) i (0.7048 to 0.7103), low ε Nd (t) (−12.3 to −5.7), low ε Hf (t) (−16.5 to −8.0) and low (206Pb/204Pb) i (18.79–18.85). These Mesozoic dykes are best understood as resulting from melting of geochemically enriched sub-continental lithospheric mantle (SCLM), whose geochemical enrichment is consistent with prior metasomatism with the agent being hydrous melt coming from subduction of the Paleo-Pacific plate at ~120 Ma or earlier. Similar to the present-day situation, the paleo-Pacific slab may have also existed stagnant in the mantle transition zone in the Mesozoic. The slab dehydrated and released water in the form of hydrous melt that percolated through and metasomatized the mantle lithosphere, and weakened the base of the lithosphere while producing basaltic melts that evolved to intermediate-felsic compositions of these dykes. The basaltic magmas that underplated and melted the lower crust to generate the widespread Mesozoic granitoids in eastern continental China. Highlights • Our K–Ar and zircon dates indicate that the dykes from the eastern China occurred in the Early Cretaceous (130-110 Ma). • The dykes resulted from partial melting of metasomatized lithospheric mantle. • We interpret this volcanism as indicating the lithosphere thinning in the eastern China. [ABSTRACT FROM AUTHOR]

Abstract Jurassic-Cretaceous granitoids are widespread in eastern continental China and have been considered by many as resulting from paleo-Pacific subduction. However, the actual mechanism of their petrogenesis remains speculative. In order to address this important problem and on the basis of our regional study, we hypothesized that the coastal granitoids may result directly from the paleo-Pacific plate subduction, whereas the widespread granitoids in the continental interiors ultimately result from dehydration of the paleo-Pacific slab stagnated in the mantle transition zone (Niu et al., 2015). Here, we present the very first study testing this hypothesis. We sampled 18 Jurassic-Cretaceous granitoid plutons along a ~ 1300 km long traverse parallel to the inferred paleo-Pacific subduction from the southeast coastline to the Xiaoqinling in the continental interiors and carried out a detailed study on these plutonic samples, including zircon U Pb geochronology, bulk-rock major and trace element compositions and Sr-Nd-Pb-Hf isotopic characteristics. These plutons give varying zircon crystallization ages of ~146 to 100 Ma. They are mostly granitic and minor granodioritic, quartz monzonitic and syenitic in composition, enriched in large ion lithophile elements (LILEs), depleted in high field-strength elements (HFSEs) and have varying negative Sr and Eu anomalies. The plutons in the continental interiors show significant positive correlations of Nd (ε Nd (t) = −25.5 to −10.9) and Hf (ε Hf (t) = −31.5 to −11.3) isotopes with Pb isotopes (206Pb/204Pb (t) = 15.827 to 17.622), with the enriched endmember characterized by low ε Nd (t), ε Hf (t) and 206Pb/204Pb (t). The plutons towards the coastal region have relatively high ε Nd (t) (−9.0 to −5.2), ε Hf (t) (−11.2 to −4.1) and 206Pb/204Pb (t) (18.051 to 18.349). The coastal granitoids are best explained as resulting directly from subduction slab dehydration induced mantle wedge melting and resultant crustal anatexis, whereas the interior granitoids are best interpreted as resulting from mature crustal anataxis caused by basaltic magmatism associated with mantle lithosphere thinning, ultimately triggered by dehydration of paleo-Pacific slab stagnant in the mantle transition zone. Highlights • The interior granitoids have different sources and petrogenesis than coastal granitoids. • The interior granitoids result from basal hydration weakening induced crustal melting. • The coastal granitoids result directly from the paleo-Pacific plate subduction. [ABSTRACT FROM AUTHOR]

Abstract The sucrose nonfermenting 1 (SNF1)-related protein kinase 2 (SnRK2) genes play central roles in plant stress signal transduction. In this study, 8 SnRK2 genes were identified from the tea plant genome database and named CsSnRK2.1-8. Phylogenetic analysis showed that the CsSnRK2 genes were classifiable into three groups, similar to those of Arabidopsis thaliana , Oryza sativa and maize. The coding sequences (CDSs) of all CsSnRK2s were separated by eight introns, and their exon-intron organizations exhibited high similarity to those of other plants. The fluorescence of GFP fused with CsSnRK2.3 was detected in only the cytoplasm, while the rest of the proteins showed GFP signal in both the nucleus and the cytoplasm. The results of the expression patterns of the CsSnRK2 genes showed that CsSnRK2s were differentially induced by salt, polyethylene glycol (PEG) and abscisic acid (ABA) stress. Interestingly, The expression of CsSnRK2.3 was inhibited by ABA, suggesting the complicated roles of CsSnRK2s in the ABA signal transduction pathway. Some CsSnRK2 gene pairs showed significant expression change correlations under stresses, indicating that CsSnRK2s might exhibit synergistic effects of signal regulation in response to various stresses. In summary, this comprehensive analysis will facilitate further studies of the SnRK2 family of Camellia sinensis and provide useful information for the functional validation of CsSnRK2s. Highlights • We identified and characterized 8 CsSnRK2 genes and explored the expression under abiotic stresses. • We explored the subcellular localizations of CsSnRK2s. [ABSTRACT FROM AUTHOR]

A series of KBa 2−x−y (PO 3 ) 5 :xTb 3+ , yCe 3+ phosphors have been synthesized by the conventional high temperature solid-state reaction method. The crystal structure, the morphology, and the luminescent properties were investigated by X-ray power diffraction (XRD), scanning electron microscopy (SEM) and photoluminescence spectra (PL). In the Ce 3+ and Tb 3+ co-doped system, the efficient energy transfer mechanism has been demonstrated to be an electric dipole-dipole interaction. The experimental results show that the optimum Tb 3+ and Ce 3+ doping concentrations are 0.4 and 0.01, respectively. The new phosphor of KBa 1.59 (PO 3 ) 5 :0.4Tb 3+ , 0.01Ce 3+ shows remarkable CIE chromaticity coordinates, indicating that it has potential application as a green-emitting phosphor in white light-emitting diodes (W-LEDs). [ABSTRACT FROM AUTHOR]

We present geochemical and age data for coeval basalt and rhyolite in the Yinshan Block, western North China Craton, to study the origin of the ‘Daly Gap’ in this bimodal volcanic suite. SHRIMP zircon U-Pb dating for felsic rocks and bulk rock 40 Ar/ 39 Ar dating for mafic rocks yield their ages of 107–133 Ma. The basalts show elevated abundances of incompatible elements with [La/Sm] N  = 2.65–3.54 and enriched Sr-Nd-Hf isotopic signatures ( 87 Sr/ 86 Sr(t) = 0.7054–0.7084, 143 Nd/ 144 Nd(t) = 0.5119–0.5123, 176 Hf/ 177 Hf(t) = 0.2824–0.2826), consistent with their derivation from low degree melting of previously metasomatized lithospheric mantle. The rhyolites display similar enrichment in alkalis and other incompatible elements, but have obvious Nb-Ta depletion. Combined with their more enriched Nd-Hf isotopic compositions (ε Nd (t) = −12 to −18, ε Hf (t) = −2 to −14), these rhyolites are inferred to have been generated by mixing of the mantle-derived basaltic magma with felsic melts derived from lower continental crust anataxis induced by the basaltic magma. Furthermore, the extremely low Ba, Sr, Eu contents, high Rb/Sr ratios and unexpectedly high 87 Sr/ 86 Sr (0.7920–0.7159) in these felsic samples also suggests that their parental magma experienced protracted fractional crystallization of plagioclase (K-feldspar to a lesser extent) en route to the surface. This rock association and the unique geochemical characteristics of these volcanic rocks offer a new view on the petrogenesis of bimodal volcanism: the mafic rocks originated from partial melting of the ancient lithospheric mantle. Underplating of the basaltic magmas triggered melting of lower continental crust. The extensive fractional crystallization of the hybridized magma resulted in the highly fractionated rhyolites. This mechanism explains the “Daly Gap” exhibited in this rock association in a continental setting and also the observation that both the lithospheric mantle and crust in East China are thinner than that in West China. [ABSTRACT FROM AUTHOR]

Background & Aims Intrahepatic cholangiocarcinoma (ICC) is the second-most lethal primary liver cancer. Little is known about intratumoral heterogeneity (ITH) and its impact on ICC progression. We aimed to investigate the ITH of ICC in the hope of helping to develop new therapeutic strategies. Methods We obtained 69 spatially distinct regions from six operable ICCs. Patient-derived primary cancer cells (PDPCs) were established for each region, followed by whole-exome sequencing (WES) and multi-level validation. Results We observed widespread ITH for both somatic mutations and clonal architecture, shaped by multiple mechanisms, like clonal “illusion”, parallel evolution and chromosome instability. A median of 60.3% of mutations were heterogeneous, among which 85% of the driver mutations were located on the branches of tumor phylogenetic trees. Many truncal and clonal driver mutations occurred in tumor suppressor genes, such as TP53 , SMARCB1 and PBRM1 that are involved in DNA repair and chromatin-remodeling. Genome doubling occurred in most cases (5/6) after the accumulation of truncal mutations and was shared by all intratumoral sub-regions. In all cases, ongoing chromosomal instability is evident throughout the evolutionary trajectory of ICC. The recurrence of ICC1239 provided evidence to support the polyclonal metastatic seeding in ICC. The change of mutation landscape and internal diversity among subclones during metastasis, such as the loss of chemoresistance mediator, can be used for new treatment strategies. Targeted therapy against truncal alterations, such as IDH1, JAK1, and KRAS mutations and EGFR amplification, was developed in 5/6 patients. Conclusions Integrated investigations of spatial ITH and clonal evolution may provide an important molecular foundation for enhanced understanding of tumorigenesis and progression in ICC. Lay summary We applied multiregional whole-exome sequencing to investigate the evolution of intrahepatic cholangiocarcinoma (ICC). The results revealed that many factors, such as parallel evolution and chromosome instability, may participate and promote the branch diversity of ICC. Interestingly, in one patient with primary and recurrent metastatic tumors, we found evidence of polyclonal metastatic seeding, indicating that symbiotic communities of multiple clones existed and were maintained during metastasis. More realistically, some truncal alterations, such as IDH1, JAK1, and KRAS mutations and EGFR amplification, could be promising treatment targets in patients with ICC. [ABSTRACT FROM AUTHOR]

The East Kunlun Orogenic Belt (EKOB), an important part of the Greater Tibetan Plateau, is an ideal region for understanding the tectonic evolution of the Anyemaqen Ocean. Here, we present zircon U–Pb ages, bulk-rock major and trace element analyses and Sr–Nd–Hf isotope compositions on representative samples of the syn-collisional Dulan batholith at the eastern end of the EKOB. The zircon U–Pb age data indicate that the bulk of the Dulan batholith was emplaced at 240–235 Ma. The granitoids have high- to medium-K and metaluminous characteristics. They are enriched in large ion lithophile elements (LILEs) and light rare earth elements (LREEs) and depleted in some high field strength elements (HFSEs, e.g., Nb and Ta), while having a flat heavy REE (HREEs) pattern. The mafic magmatic enclaves (MMEs) share the same age, mineralogy and indistinguishable Sr–Nd–Hf isotopes with their granitoid hosts except for the higher HREE abundances. We show that the MMEs represent cumulate formed at earlier stages of the same magmatic system. The trace element data (e.g., Nb/Th, Ta/U) and inherited mantle isotopic characteristics of the Dulan batholith are also consistent with an origin via partial melting of the last fragments of underthrusting ocean crust. Simple mass balance calculations using the Sr–Nd–Hf isotopic data show that ~ 85% Paleo-Tethys MORB and ~ 15% mature crustal material (the Proterozoic gneiss of the study area) contribute to the source of the granitoids. The Dulan batholith shows compositional similarities to the bulk continental curst with inherited mantle isotopic signatures. The syn-collisional felsic magmatism must have contributed to the net continental crust growth in the EKOB. We infer that the Kunlun and Qinling orogens may actually be one single orogen offset later by the Wenquan fault system. [ABSTRACT FROM AUTHOR]

Abstract Inductively coupled plasma mass spectrometry (ICP-MS) is the most commonly used technique to determine the abundances of trace elements in a wide range of geological materials. However, incomplete sample digestion, isobaric interferences and instrumental drift remain obvious problems that must be overcome in order to obtain precise and accurate results. For this reason, we have done many experiments and developed a set of simple, cost-effective and practical methods widely applicable for precise and rapid determination of trace element abundances in geological materials using ICP-MS. Commonly used high-pressure digestion technique is indeed effective in decomposing refractory phases, but this inevitably produces fluoride complexes that create new problems. We demonstrate that the fluoride complexes formed during high-pressure digestion can be readily re-dissolved using high-pressure vessel at 190 °C for only 2 h for 50 mg sample. In the case of isobaric interferences, although oxide (e.g., MO+/M+) and hydroxide (e.g., MOH+/M+) productivity is variable between runs, the (MO+/M+)/(CeO+/Ce+) and (MOH+/M+)/(CeO+/Ce+) ratios remain constant, making isobaric interference correction for all other elements of interest straightforward, for which we provide an easy-to-use off-line procedure. We also show that mass-time-intensity drift curve is smooth as recognized previously, for which the correction can be readily done by analyzing a quality-control (QC) solution and using off-line Excel VBA procedure without internal standards. With these methods, we can produce data in reasonable agreement with recommended values of international rock reference standards with a relative error of <8% and precision generally better than 5%. Importantly, compared to the widely used analytical practice, we can effectively save >60% of time (e.g., <24 h vs. >60 h). [ABSTRACT FROM AUTHOR]

Studies of mid-ocean ridge basalts (MORB) show a variable Fe isotope composition of the oceanic upper mantle. To test a recent hypothesis that heavy Fe isotope enrichment in the MORB mantle results from the same process of incompatible element enrichment, we conduct an Fe isotope study of well-characterized MORB samples from a magmatically robust segment (OH-1) of the Mid-Atlantic Ridge (MAR) at ∼ 35°N. The data show large Fe isotope variation (δ 56 Fe = +0.03 to +0.18‰) that correlates well with the abundances and ratios of more-to-less incompatible elements and with Sr-Nd-Hf isotopes. Our findings in support of the hypothesis can be detailed as follows: (1) the oceanic upper mantle has a heterogeneous Fe isotope composition on varying small spatial scales with isotopically heavy Fe (high- δ 56 Fe) preferentially associated with pyroxenite lithologies; (2) such lithologies, which are also enriched in the progressively more incompatible elements, are of low-degree (low-F) melt metasomatic origin; (3) with all the conceivable processes considered, the low-F melt metasomatism takes place at the lithosphere-asthenosphere boundary (LAB) beneath ocean basins through crystallization of incipient (Low-F) melt in the seismic low velocity zone (LVZ) at the base of the growing oceanic lithosphere (i.e., LAB) over the Earth's history since the onset of plate tectonics, forming composite lithologies with geochemically enriched pyroxenite veins dispersed in the depleted peridotite matrix; (4) such mantle of composite lithology when transported to beneath the present-day ocean ridges will undergo decompression melting and produce MORB melts with geochemical trends of "melting-induced mixing" as observed at the MAR and global MORB; (5) we predict all this to be a globally common process and widespread. • Large Fe isotope compositional variation is observed in OH-1 MORB lavas from Mid-Atlantic Ridge at ∼35° N. • Heavy Fe isotope enrichment in the MORB mantle results from the low-degree melts metasomatism. • The heavy Fe isotope enrichment process of low-degree melt mantle metasomatism is globally widespread. • Large δ 56 Fe variations in global MORB results from melting-induced mixing of the heterogenous upper mantle. [ABSTRACT FROM AUTHOR]

We present a detailed study of geochronology, mineral chemistries, bulk-rock major and trace element abundances, and Sr–Nd–Hf isotope compositions of the granodiorite and associated dioritic dikes in the Hongqilafu pluton at the northwestern margin of the Tibetan Plateau. The granodiorite and dioritic dikes yielded zircon U–Pb ages of ~ 104 Ma and ~ 100 Ma, respectively. The dioritic dikes comprise varying lithologies of gabbroic diorite, diorite porphyry and granodiorite porphyry, exhibiting a compositional spectrum from intermediate to felsic rocks. Their mineral compositions display disequilibrium features such as large major element compositional variations of plagioclase, clinopyroxene and amphibole crystals. These dioritic dikes are enriched in incompatible elements (Ba, Rb, Th, U, K) and Sr–Nd–Hf isotopes ( 87 Sr/ 86 Sr i : 0.7066 to 0.7071, ε Nd (t): − 5.3 to − 7.4, ε Hf (t): − 3.6 to − 6.2). We suggest that the dioritic dikes were most likely derived from partial melting of mantle wedge metasomatized by the subducted/subducting seafloor with a sediment component, followed by AFC processes with fractional crystallization of clinopyroxene, amphibole and plagioclase and assimilation of lower continental crust. The mantle-wedge derived magma parental to the dioritic dikes underplated and induced the lower continental crust to melt, forming the felsic crustal magma parental to the granodiorite with mantle melt signatures and having more enriched isotope compositions ( 87 Sr/ 86 Sr i : 0.7087 to 0.7125, ε Nd (t): − 9.5 to − 11.6, ε Hf (t): − 10.3 to − 14.1) than those of the dioritic dikes. The Hongqilafu pluton is thus the product of mantle–crust interaction at an active continental margin subduction setting over the period of several million years. This understanding further indicates that the closure timing of the Shyok back-arc basin and the collision between the Kohistan–Ladakh Arc and the Karakoram Terrane may have taken place later than ~ 100 Ma. [ABSTRACT FROM AUTHOR]

The West Kunlun orogenic belt (WKOB) at the northwest margin of the Greater Tibetan Plateau records seafloor subduction, ocean basin closing and continental collision with abundant syncollisional granitoids in response to the evolution of the Proto- and Paleo-Tethys Oceans from the early-Paleozoic to the Triassic. Here we present a combined study of detailed zircon U-Pb geochronology, whole-rock major and trace elements and Sr-Nd-Hf isotopic geochemistry on the syncollisional Arkarz (AKAZ) pluton with mafic magmatic enclaves (MMEs) exposed north of the Mazha-Kangxiwa suture (MKS) zone. The granitoid host rocks and MMEs of the AKAZ pluton give the same late Triassic age of ~ 225 Ma. The granitoid host rocks are metaluminous granodiorite and monzogranite. They have initial 87 Sr/ 86 Sr of 0.70818 to 0.70930, ε Nd (225 Ma) = − 4.61 to − 3.91 and ε Hf (225 Ma) = − 3.01 to 0.74. The MMEs are more mafic than the host with varying SiO 2 (51.00–63.24 wt.%) and relatively low K 2 O (1.24–3.02 wt.%), but have similar Sr-Nd-Hf isotope compositions to the host (( 87 Sr/ 86 Sr) i = 0.70830–0.70955, ε Nd (225 Ma) = − 4.88 to − 4.29, ε Hf (225 Ma) = − 2.57 to 0.25). Both the host and MMEs have rare earth element (REE) and trace element patterns resembling those of bulk continental crust (BCC). The MMEs most likely represent cumulate formed from common magmas parental to the granitoid host. The granitoid magmatism is best explained as resulting from melting of amphibolite of MORB protolith during continental collision, which produces andesitic melts with a remarkable compositional similarity to the BCC and the inherited mantle-like isotopic compositions. Simple isotopic mixing calculations suggest that ~ 80% ocean crust and ~ 20% continental materials contribute to the source of the AKAZ pluton. Thus, the hypothesis “continental collision zones as primary sites for net continental crust growth” is applicable in the WKOB as shown by studies in southern Tibet, East Kunlun and Qilian orogens. In addition, we also propose a new view for the tectonic evolution of the Paleo-Tethys Ocean in geological regions recorded and represented by the MKS. [ABSTRACT FROM AUTHOR]

The effect of paleo-Pacific subduction on the geological evolution of the western Pacific and continental China is likely complex. Nevertheless, our analysis of the distribution of Mesozoic granitoids in the eastern continental China in space and time has led us to an interesting conclusion: The basement of the continental shelf beneath East and South China Seas may actually be of exotic origin geologically unrelated to the continental lithosphere of eastern China. By accepting the notion that the Jurassic-Cretaceous granitoids in the region are genetically associated with western Pacific subduction and the concept that subduction may cease to continue only if the trench is being jammed, then the termination of the granitoid magmatism throughout the vast region at ~88 ± 2 Ma manifests the likelihood of 'sudden', or shortly beforehand (~100 Ma), trench jam of the Mesozoic western Pacific subduction. Trench jam happens if the incoming 'plate' or portion of the plate contains a sizeable mass that is too buoyant to subduct. The best candidate for such a buoyant and unsubductable mass is either an oceanic plateau or a micro-continent. We hypothesize that the basement of the Chinese continental shelf represents such an exotic, buoyant and unsubductable mass, rather than seaward extension of the continental lithosphere of eastern China. The locus of the jammed trench (i.e., the suture) is predictably located on the shelf in the vicinity of, and parallel to, the arc-curved coastal line of the southeast continental China. It is not straightforward to locate the locus in the northern section of the East China Sea shelf because of the more recent (<20 Ma) tectonic re-organization associated with the opening of the Sea of Japan. We predict that the trench jam at ~100 Ma led to the re-orientation of the Pacific plate motion in the course of NNW direction as inferred from the age-progressive Emperor Seamount Chain of Hawaiian hotspot origin (its oldest unsubdued Meiji and Detroit seamounts are ~82 Ma), making the boundary between the Pacific plate and the newly accreted plate of eastern Asia a transform fault at the location east of the continental shelf of exotic origin. This explains the apparent ~40 Myr magmatic gap from ~88 to ~50 Ma prior to present-day western Pacific subduction initiation. We propose that basement penetration drilling on well-chosen sites is needed to test the hypothesis in order to reveal the true nature of the Chinese continental shelf basement. This testing becomes critical and cannot longer be neglected in order to genuinely understand the tectonic evolution of the western Pacific and its effect on the geology of eastern China since the Mesozoic, including the cratonic lithosphere thinning, related magmatism/mineralization, and the mechanism of the subsequent South China Sea opening, while also offering novel perspectives on aspects of the plate tectonics theory. We also suggest the importance of future plate tectonic reconstruction of the western Pacific to consider the nature and histories of the Chinese continental shelf of exotic origin as well as the probable transform plate boundary from ~100 to ~50 Ma. Effort is needed to reveal the true nature and origin of the ~88 ± 2 Ma granitic gneisses in Taiwan and the 110-88 Ma granitoids on the Hainan Island. [ABSTRACT FROM AUTHOR]

In this study, the microstructure evolution and mechanical properties of Mg-15Gd-1Zn-0.4Zr (GZ151K, wt%) alloys treated by ultrasonic surface rolling process (USRP) were investigated. Microscopic analysis methods, including atomic force microscopy, electron backscatter diffraction, scanning electron microscopy, energy-dispersive X-ray spectroscopy, and X-ray diffraction, as well as mechanical performance tests, including microhardness and uniaxial tensile tests, were employed to analyse the strengthening mechanisms of the GZ151K alloy deformed by the USRP. Results showed that the surface morphology of the alloy was significantly improved compared to that of the untreated sample. In addition, the deformation process of GZ151K alloy introduced a large number of twins and dislocations inner the grains, and formed twin and dislocation gradient structures due to the stress/strain gradient along the normal direction. Furthermore, twinning deformation and dislocation slip during USRP alternately occurred and competed with each other to form a higher volume fraction of sub-grains and twin boundaries. Therefore, the microhardness and tensile strength after USRP were significantly enhanced by twin boundaries and dislocation strengthening, whereas the ductility decreased owing to the initiation and extension of microcracks. However, when the pressure during the USRP was 0.3 MPa, minimal surface roughness and superior mechanical properties could be achieved under the twin and dislocation strengthening. • The twin and dislocation gradient of GZ151K magnesium was found by electron backscatter diffraction. • The mechanical performance and strengthening mechanisms of gradient nano-twin GZ151K alloy were obtained. • The microstructural and textural evolution of gradient nano-twin GZ151K alloy was displayed. [ABSTRACT FROM AUTHOR]

The Sumdo Paleo-Tethys Ocean was the southernmost part of the Paleo-Tethys Ocean and was located on the Qinghai–Tibet Plateau. Doubts exist as to the internal dynamics and evolution of the Sumdo Paleo-Tethys Ocean region during the Permian, owing to insufficient knowledge regarding the remnants of oceanic crust. Here, we report results for petrology, laser ablation–inductively coupled plasma–mass spectrometry zircon U Pb dating, whole-rock geochemistry, and zircon Hf and whole-rock Sr Nd isotopes of mafic rocks in the Sumdo area. Geochemical characteristics of these mafic rocks allow them to be divided into two groups, A and B. Group A rocks are characterized by high SiO 2 and TiO 2 contents, low Al 2 O 3 contents, and Na 2 O > K 2 O. Their chondrite-normalized rare-earth-element (REE) and primitive-mantle-normalized trace-element patterns are similar to those of N-MORB. The samples exhibit enrichment in U and depletion in Th, depletion in light REEs, and high 143Nd/144Nd values. Group B rocks have high SiO 2 , TiO 2 , and Al 2 O 3 contents. Their chondrite-normalized REE patterns and primitive-mantle-normalized trace-element patterns are similar to those of E -MORB. Group B rocks are enriched in Nb and Ta, depleted in Th and U, and show high 87Sr/86Sr and low 143Nd/144Nd values. Zircon U Pb dating of five meta-gabbro rock samples yielded ages of 268.9 ± 1.6 Ma (STN66), 273.8 ± 2.2 Ma (STN79), 265.1 ± 4.1 Ma (STE26), 258.7 ± 4.4 Ma (STE89), and 261.0 ± 3.1 and 263.7 ± 5.4 Ma (STE41). STN79 shows N-MORB geochemical characteristics and has ε Hf (t) values of +12.4 to +14.6, whereas STE41 displays E -MORB geochemical characteristics with ε Hf (t) values of −2.6 to +0.4. The Sumdo mafic rocks were not contaminated by subducted sediments and/or slab-derived fluids, and formed in a mid-ocean ridge setting. Combining results of previous studies with our new geochemical data for mafic rocks in the Sumdo area, we infer the occurrence of plume/hotspot–ridge interaction in the Sumdo Paleo-Tethys Ocean during the middle–late Permian. Mixing of mantle plume/hotspot melt and depleted asthenospheric mantle explains the origin of basaltic magma that formed rocks with the observed geochemical and isotopic characteristics in the Sumdo area. • The Sumdo mafic rocks are formed in a MOR setting during the middle–late Permian. • The mafic rocks in Sumdo show a continuous evolution from N-MORB to E-MORB to OIB. • The genesis of the mafic rocks was related to plume/hotspot-ridge interaction. [ABSTRACT FROM AUTHOR]

• The newly discovered Middle Permian granite dikes are adakitic in composition. • The adakitic magma was generated by partial melting of subducted oceanic slab. • The granite dikes were related to the subduction of the Sumdo Paleo-Tethys Ocean. The Sumdo Paleo-Tethys Ocean was the southernmost part of the Paleo-Tethys Ocean, located on the Qinghai–Tibet Plateau. However, the evolution of the Sumdo Paleo-Tethys Ocean and the origin of eclogites in the Sumdo area of Tibet are still matters of debate. Here we report newly discovered adakitic granite dikes from the Sumdo area of the central Lhasa terrane. The rocks have high SiO 2 , Al 2 O 3 , and Sr contents, high Sr/Y and La/Yb ratios, enrichment in light rare-earth elements (REEs), and depletion in Y, Yb, Th, and heavy REEs. They are characterized by low 87Sr/86Sr (0.703678–0.704427) and high 143Nd/144Nd (0.512825–0.512904) ratios, and positive ε Nd (t) (+6.41 to +7.38) and ε Hf (t) (+13.8 to +15.7) values. Zircon U–Pb dating yielded ages of 269.1 ± 4.1 and 266.4 ± 2.0 Ma for the rocks. Our data indicate that the Sumdo adakitic granite dikes were derived from partial melting of subducted oceanic slab, with the magma being influenced by slab-derived fluids and slight interaction with peridotite in the mantle wedge during ascent. By combining our new geochemical data with results of previous studies, we infer a subduction event involving the Sumdo Paleo-Tethys Ocean during the middle Permian, which led to the formation of the Sumdo adakitic granite dikes and the Sumdo, Jilang, and Xindaduo eclogites. [ABSTRACT FROM AUTHOR]

Abstract: A new method is studied for preparing nano-ceria by acid leaching MgO from CeO2−MgO mixed powder made by calcining a gel. The MgO in the mixed powder can be leached completely with acetic acid solution at room temperature, but the CeO2 remains unaffected. The surface area (Sg) of the resulting CeO2 increases with Mg/Ce ratio, but approaches constant after the ratio is larger than a given value which is higher for the higher gel calcining temperature. When Mg/Ce is 8 (molar ratio) and the calcining temperature is 1253 K, the Sg of the resulting ceria remains 25.1 m2/g even after annealed at 1253 K for 4 h. In comparison with the conventional methods, CeO2 from the new method shows higher surface area and higher thermal stability. [Copyright &y& Elsevier]

B Summary: b This video demonstrates laparoscopic anatomical S7 segmentectomy with ICG positive staining by laparoscopic ultrasound (US) and 3D visualization guided portal branch puncture approach. The branche of S7 were identified by laparoscopic US and punctured with the 22-gauge PTCD needle through the abdominal wall under laparoscopic US and 3D visualization image guide. [Extracted from the article]

Herein, we developed laparoscopic ultrasound and 3D visualization guided portal branch puncture technique to injection ICG fluorescence dye to the visualization of segments or subsegments during pure laparoscopic anatomical hepatectomy. B Conclusion: b Laparoscopic anatomical hepatectomy with ICG fluorescence staining by lap ultrasound and 3D visualization guided portal branch puncture approach is feasible and safe. [Extracted from the article]

B Summary b This video demonstrates laparoscopic anatomical S8 segmentectomy with ICG positive staining by laparoscopic ultrasound (US) and 3D visualization guided portal branch puncture approach. Liver parenchyma was transected along the fluorescence boundary with Harmonic and CUSA under real-time fusion ICG-fluorescence imaging. [Extracted from the article]