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In this study, a series of cordierite monolithic catalysts with Ru species supported on different low-cost available carriers were prepared and investigated for the degradation of CVOCs.

The Neotethyan subduction and collision with the Asian, Indian, and Australian plates is evidenced by a giant Andean-type arc system and a remarkable Neotethyan igneous belt along the southwestern Eurasian margin. However, the southward extent, and cause, of Neotethyan subduction is poorly understood. Here, a zircon U-Pb dating and whole-rock geochemical study of two groups of Eocene (50−48 Ma) mafic intrusions from Tangse, North Sumatra, helps to unravel the Neotethyan subduction story. Group 1 consists of diabase samples, which have mid-oceanic-ridge− and arc-like geochemical affinities, with low chondrite-normalized La/Yb(cn) (∼0.6) ratios and a high measured εNd(t) value of +8.7. Such geochemical signatures indicate that the magmatic rocks were derived from a refractory depleted mantle source that was metasomatized by slab melts. Group 2 consists of gabbro-diorites, which are enriched in the large-ion lithophile elements and depleted in some high field strength elements. These samples have high La/Yb(cn) (2.9−6.6), low Nb/La(cn) (0.2−0.3), εNd(t) values of +1.1 to +5.0, and εHf(t) values of +8.8 to +15.3. Group 2 samples were produced by the melting of a depleted mantle wedge metasomatized by slab fluids. The magmatism provides evidence for the southern continuation of the Neotethyan igneous belt and tectonic system, whereby slab rollback triggered melting and upwelling in an arc−back-arc geodynamic system from South Tibet to SE Asia.

The geodynamic evolution of the Palaeo-Tethyan Ocean is key to understanding the development of Pangaea. The main continents of SE Asia were welded together in response to the closure of the Palaeo-Tethyan Ocean. However, the precise location of the sutures and timing of the collisions are poorly constrained, especially the southward continuation from Peninsular Malaysia into west Indonesia. This study presents new zircon U–Pb geochronological, petrological, elemental and Sr–Nd–Pb–Hf–O isotopic data in order to investigate the origin and tectonic setting of the granitoids from the Bangka and Belitung islands, west Indonesia. Although possessing different mineral compositions, the two groups of samples yield similar crystallization ages of c. 230–220 Ma and enriched Nd–Hf isotopic compositions (whole-rock ε Nd ( t ) = −9.6 to −2.4 and zircon ε Hf ( t ) = −12.1 to −0.1), and probably originated from melting of a mixed source of metagreywacke and metapelite with a subordinate meta-igneous component. Both granitic groups formed during post-collisional processes, and when this interpretation is combined with regional investigations on the granitic magmatism, the Bangka–Belitung granitoids may represent the southward continuation of the Main Range granitoids. If correct, the distribution of granitoids with distinct petrogenesis across both islands implies a location for the Palaeo-Tethyan suture zone between Bangka–Belitung and West Kalimantan.

We investigated the effect of pegylated recombinant human granulocyte colony-stimulating factor (PEG-rhG-CSF) on lymphocytes and white blood cells of patients with malignant tumors. After PEG-rhG-CSF treatment, the count of lymphocytes increased in 66 cases, remained unchanged in 2 cases, and decreased in 20 cases. The difference in lymphocyte count before and after treatment was statistically significant (P < 0.001). White blood cell changes were positively correlated with lymphocyte changes (r = 0.36, P = 0.001). In the subgroup with increased white blood cells (n = 80), there were 62 cases with increased lymphocytes, 1 case with unchanged lymphocytes, and 17 cases with decreased lymphocytes after PEG-rhG-CSF treatment. There was significant difference in the count of lymphocytes and white blood cells (P < 0.001). In the subgroup with 6 mg of PEG-rhG-CSF (n = 66) and the subgroup with 3 mg of PEG-rhG-CSF (n = 22), the changes of white blood cell and lymphocyte counts before and after treatment were statistically significant (P < 0.001). The two were positively correlated in the 6 mg PEG-rhG-CSF subgroup, with correlation coefficient r = 0.34 (P = 0.002). PEG-rhG-CSF can increase the count of lymphocytes and white blood cells in patients with malignant tumors, and the increase of lymphocytes is positively correlated with the increase of white blood cells.

The Lincang-Inthanon tectonic belt is a major tectonic boundary within the southeastern Tibetan Plateau and Indo-China Peninsula, which are typical examples of tectonic extrusion in SE Asia. The Lincang strain zone, Lancang-Gengma fault, and Inthanon metamorphic complex make up this nearly N–S-striking tectonic belt, which separates the Baoshan–Shan Thai and Simao-Indochina terranes. New petrographic, structural, and mica 40Ar/39Ar geochronological studies were conducted to reveal their deformation styles and constrain the timing of their tectonic evolution. W–E-directed compression related to the subduction of the Paleotethyan Ocean with subsequent continental collision and sinistral ductile shearing in the early Oligocene are recorded along the Lincang strain zone. The Lancang-Gengma fault zone switched from sinistral shearing to dextral motion in the late Cenozoic and shows a deformation history similar to that of the parallel Red River fault. The Inthanon metamorphic complex may have experienced crustal shortening in the early Cenozoic, followed by sinistral transtension in the early Miocene. The Lincang-Inthanon tectonic belt shows many lithological, tectonic evolutionary, and metamorphic similarities with the Gaoligong, Chongshan, and Ailaoshan–Red River shear zones. Therefore, the sinistral shearing along the Lincang-Inthanon tectonic belt and the Chongshan shear zone in the north, which may have initiated since the early Oligocene, played an important role in adjusting differential extrusion and rotation of the Baoshan–Shan Thai and Simao-Indochina terranes. Our results delineate the regional tectonic framework and provide insights into the characteristics and geodynamics of intracontinental deformation in the eastern India-Eurasia oblique convergence zone.

The Kuching zone in NW Kalimantan and Malaysia Sarawak might be the southerly-extending segment of the paleo-Pacific subduction that is developed along the Coastal South China and SE Vietnam, and separated the Sundaland “old-land” from the Cenozoic Sibu zone. However, establishing this link is hindered by the lack of data on the Mesozoic orogenic history in NW Kalimantan. This paper presents zircon U-Pb geochronological and Hf-O isotopic data as well as whole-rock elemental and Sr-Nd-Pb isotopic results for the Raya Volcanics and their equivalents, as well as the Mensibau batholith in NW Kalimantan. The Raya Volcanics and Mensibau granitoids formed at 130–144 Ma, synchronous with the Menunuk Volcanics, but significantly older than the Pakong-Serabang mafic rocks and Serian Volcanics (~77–98 Ma) in the Sarawak Kuching zone. The Raya Volcanics and their equivalents belong compositionally to tholeiitic to low-K calc-alkaline series, and exhibit “spiky” PM-normalized patterns with Nb/La = 0.16–0.32, (87Sr/86Sr)i = 0.70187–0.70671 and eNd(t) = +0.9 to +3.6. Their (206Pb/204Pb)i, (208Pb/204Pb)i and (207Pb/204Pb)i range from 18.49 to 18.83, 38.39 to 39.19 and 15.57 to 15.70, and zircon eHf(t)-δ18O values from +4.1 to +16.1, and 5.21‰ to 6.05‰, respectively. They are derived from mantle wedge modified by recycled sediments. The Mensibau batholith is dominated by I-type granodiorite and granite. They share similar elemental ratios and Sr-Nd-Pb-Hf-O isotopic compositions with the Raya Volcanics, and originated from wedge-derived juvenile mafic crust. The temporal-spatial and geochemical accordance for the Raya Volcanics and Mensibau batholith document the extensive development of the early Cretaceous igneous rocks in NW Kalimantan. The Kuching zone is a northeasterly-propagated Cretaceous accretionary system that developed in response to the subduction of the paleo-Pacific plate.

Introduction Although numerous land cover datasets can act as references for understanding land cover change in China, the inconsistencies between the datasets can also provide understanding. Previous studies on the consistency between land cover datasets have mostly focused on land cover type consistencies and have ignored data consistencies in land cover change. Outcomes Therefore, we aim to analyse the consistencies in land cover changes through likelihood assessment methods. We compared the spatiotemporal changes in forest, grassland, cropland, and bare land in the Climate Change Initiative land cover dataset (CCI-LC), Moderate-resolution Resolution Imaging Spectroradiometer land cover dataset (MCD12Q1), China’s National Land Use and Cover Change (CNLUCC), Globeland30 and Global Land Cover Fine Surface Covering 30 (GLC-FCS30) datasets in 2010. The results showed that the percentages and changes in each land cover type in MCD12Q1 were different from those in the other datasets. Discussion For example, the proportion of grassland in MCD12Q1 was the highest, reaching 48.04%. The places with high consistency were the places where the land cover types were concentrated, and the bare land had the highest consistency. However, the consistency of China’s land cover change was quite low, and the percentage of low consistency was more than 87% from 2000-2018. Comparison of the data with the global artificial impervious area (GAIA) and Hansen-Global Forest Change (Hansen-GFC) datasets showed that the percentage of high construction gain consistency (38.83%) was higher than the forest change consistency, and the percentage forest loss high consistency (8.85%) was lower than the forest gain high consistency (12.76%). Conclusion The results not only provide a basis for the use of land cover datasets but also give a clearer understanding of the pattern of land cover changes.

The Jurassic magmatism in the southeastern South China Block has been interpreted as extension-related, yet its tectonic drivers remain unclear. Tectonic models vary between two end-members: (1) Palaeopacific subduction-related; and (2) intracontinental extension-related. This study presents new geochronological and geochemical data for the Late Jurassic mafic rocks in the southeastern South China Block that allow us to differentiate between these tectonic models. The Late Jurassic mafic rocks yielded crystallization ages of 162–157 Ma. Our new geochemical data, together with previously published data, can be divided into three groups: group A with variable ε Nd ( t ) (+0.1 to +3.4) and zircon ε Hf ( t ) (−4.1 to +15.9) values has slightly negative Nb–Ta anomalies; group B is characterized by negative Nb–Ta anomalies with varying ε Nd ( t ) (+1.4 to +1.5) and ε Hf ( t ) (–3.0 to +2.6) values; and group C displays significant Nb–Ta anomalies with high ε Nd ( t ) (+4.5 to +6.6) and ε Hf ( t ) (+6.4 to +14.4) values. The geochemical characteristics suggest that groups A and B are mainly the products of asthenosphere–lithosphere interactions and group C was derived from the asthenosphere. Our new data, together with geological observations, suggest that the Late Jurassic magmatism in the southeastern South China Block probably resulted from asthenospheric upwelling in an intracontinental extension setting due to the far-field effects of the subduction of the Palaeopacific Ocean. Supplementary material: Tables of geochronological data, geochemical data, and additional figures are available at https://doi.org/10.6084/m9.figshare.c.6080871

Cretaceous igneous rocks in SW Borneo are significant for investigating the Paleo-Pacific subduction and regional correlation. This paper presents new zircon ages and Sr–Nd–Pb–Hf–O isotopic and whole-rock geochemical data for the Cretaceous granitoids in the Schwaner Mountains. These granitoid samples yield formation ages of 92–80 Ma and can be geochemically subdivided into Group 1 biotite granite and granodiorite and Group 2 monzogranite. Group 1 has higher εHf t values of +1.2–+14.5 and lower δ18O values of 5.2–6.6‰ than Group 2 with εHf t and δ18O values of −1.5–+5.9 and 6.1–6.6‰, respectively. Group 1 samples show variable εNd t values of −1.9–+1.7, (206Pb/204Pb)i ratios of 18.63–19.29, (207Pb/204Pb)i ratios of 15.62–15.69, and (208Pb/204Pb)i ratios of 38.67–39.49 and are the products of partial melting of newly underplated mafic rocks with a component of crustal rocks. Group 2 with slightly negative εNd t values of −1.1–−1.5 was originated from partial melting of metasedimentary rocks with a juvenile mafic component. These granitoids were formed in a continental arc setting related to the Paleo-Pacific subduction during the Late Cretaceous and can compare with those contemporaneous I-type granites along the Kuching zone in NW Borneo. Those Late Cretaceous granitoids with A-type affinities from the easternmost Peninsular Malaysia and Singapore to the east of Sundaland might be formed in a back-arc extensional setting after the Paleo-Pacific subduction.

The EW-trending Kuching zone in Borneo is a target region for exploring the southern continuation of Paleo-Pacific subduction from South China, Vietnam to SE Asia. Previous studies mainly focused on mafic igneous rocks, and poor attention has been paid to the contemporaneous granitoids in this zone. This study presented detailed zircon U-Pb geochronology and Lu-Hf isotope and whole-rock geochemistry analyses for late Cretaceous granitoids (granodiorites and granites) in the northern Kuching zone. These granitoids are dated at ~77.5-83.6 Ma with younger ages than the igneous rocks in the southern Kuching zone (~130-144 Ma). The granitoids have variable SiO2 (64.86-77.37 wt.%) and A/CNK (0.7-1.5) and are strongly enriched in LILE and depleted in HFSE with significant Ba, Nb, Sr, and Ti negative anomalies. They have variable (87Sr/86Sr)i (from 0.70656 to 0.71208), εNd(t) (from -4.4 to +0.9), and zircon εHf(t) (from -1.2 to +12.4) with high (206Pb/204Pb)i ratio of 18.78-19.74, suggesting derivation from a hybrid source involving meta-sedimentary and meta-igneous rocks. Combined with previously-published data, two episodes of Cretaceous (~77-98 Ma and ~130-144 Ma) magmatic activities are identified in the Kuching zone, showing a younging age trend from south to north. These episodes of Cretaceous igneous rocks and their spatial distribution in the Kuching zone can be totally comparable to those in South China and Vietnam. Thus, the Kuching zone was likely a part of the Paleo-Pacific subduction system during the Cretaceous, northerly linking to Vietnam and South China.

The southeastern (SE) South China Block was mainly influenced by the Paleo-Tethyan and Paleo-Pacific dynamic domains during the Mesozoic. The initial timing of the tectonic transition between these two domains in the SE South China Block still remains debated. The transition would affect the nature of the lithosphere and material provenance of sediments, and, therefore, igneous and sedimentary rocks in the area could record such dynamic processes. In this study, published geochronological and geochemical data of the Triassic and Jurassic igneous rocks and detrital zircon data of contemporaneous sedimentary rocks in the SE South China Block were compiled, aiming to provide constraints on the tectonic transition via tracing the spatial-temporal variations in the nature of the lithosphere and sedimentary provenance signals. The compiled results suggest that the magmatic intensity and volume decreased significantly from the Late Triassic to Early–Middle Jurassic, with an obvious magmatic quiescence between them, and increased from the Early–Middle Jurassic to Late Jurassic. The εNd(t) and zircon εHf(t) values of mafic rocks, granitoids, and shoshonitic rocks remarkably increased from the Late Triassic to Early–Middle Jurassic, indicative of variations in the lithospheric mantle and continental crust. Such variations suggest that the initial tectonic transition occurred at the earliest Early Jurassic. Based on the southward paleocurrents from Early Jurassic sandstone, E-W–trending extension of Early–Middle Jurassic mafic and shoshonitic rocks, and similar sedimentary provenances of Late Triassic and Early–Middle Jurassic sedimentary rocks, these features imply that the SE South China Block was not immediately influenced by the Paleo-Pacific domain during the Early–Middle Jurassic. However, from the Early–Middle Jurassic to Late Jurassic and Early Cretaceous, the spatial distribution, geochemical signatures, magmatic intensity, and magmatic volume of igneous rocks and provenance of sedimentary rocks exhibit obvious variations, and the regional fold hinge direction changed from E-W–trending to NE-trending, suggesting significant effects from Paleo-Pacific subduction on the SE South China Block. Thus, the Mesozoic tectonic transition from the Paleo-Tethyan to the Paleo-Pacific dynamic domain in the SE South China Block likely occurred during the Early–Middle Jurassic.

The Youjiang Basin is usually regarded as an important foreland basin in the southern part of the South China Block that is related to the convergence of the South China and Indochina blocks during the Permian-Triassic. However, the nature of the basin remains controversial due to questions about the subduction polarity and suture boundary between these two blocks. Permian-Triassic felsic volcanics across the Dian-Qiong and Song Ma suture zones could offer new insights into the convergent processes of the South China and Indochina blocks. This study presents detailed petrological, zircon U-Pb dating, and Hf-O isotope and whole-rock geochemical analyses for the Triassic felsic volcanics of the Youjiang Basin (northeast of the Dian-Qiong). The dacites and rhyolites from the Beisi and Baifeng Formations were dated at ca. 240–245 Ma. All of the felsic volcanics are characterized by high SiO2 (69.40–73.15 wt%), FeOt/MgO, 10000*Ga/Al, and TZr, δ18O (9.7–11.8‰) and negative εNd(t) (from −9.6 to −12.3) and zircon εHf(t) (from −6.2 to −14.5) with A-type granitoid geochemical affinities, suggesting the reworking of crustal rocks in an extensional setting. Permian-Triassic felsic igneous rocks display similar geochemical signatures across the Dian-Qiong suture zone, whereas they show distinctive Sr-Nd and zircon Hf-O isotopes across the Song Ma suture zone. The felsic igneous rocks to the northeast of the Song Ma suture zone have much lower εNd(t) and higher δ18O with negative zircon εHf(t) than those to the southwest, which have positive zircon εHf(t). Combined with other geological and geophysical features, it is inferred that the Song Ma suture zone was probably the suture boundary between the South China and Indochina blocks, and the Youjiang Basin was likely a peripheral foreland basin in response to the southwestward convergence of the South China Block toward the Indochina Block.

Renin-angiotensin system (RAS) inhibitors and calcium channel blockers (CCB) are often used together in chronic kidney disease (CKD). The PubMed, EMBASE, and Cochrane Library databases were searched to identify randomized controlled trials (RCTs) in order to explore better subtypes of CCB for the treatment of CKD. This meta-analysis of 12 RCTs with 967 CKD patients who were treated with RAS inhibitors demonstrated that, when compared with L-type CCB, N-/T-type CCB was superior in reducing urine albumin/protein excretion (SMD, −0.41; 95% CI, −0.64 to −0.18; p < 0.001) and aldosterone, without influencing serum creatinine (WMD, −3.64; 95% CI, −11.63 to 4.35; p = 0.37), glomerular filtration rate (SMD, 0.06; 95% CI, −0.13 to 0.25; p = 0.53), and adverse effects (RR, 0.95; 95% CI, 0.35 to 2.58; p = 0.93). In addition, N-/T-type CCB did not decrease the systolic blood pressure (BP) (WMD, 0.17; 95% CI, −1.05 to 1.39; p = 0.79) or diastolic BP (WMD, 0.64; 95% CI, −0.55 to 1.83; p = 0.29) when compared with L-type CCB. In CKD patients treated with RAS inhibitors, N-/T-type CCB is more effective than L-type CCB in reducing urine albumin/protein excretion without increased serum creatinine, decreased glomerular filtration rate, and increased adverse effects. The additional benefit is independent of BP and may be associated with decreased aldosterone (PROSPERO, CRD42020197560).

Objectives Dental tissue-derived mesenchymal stem cell (MSC)-mediated tooth regeneration may be a useful therapeutic tool for repairing tooth loss. However, the low success rate of tooth regeneration restricts its clinical application. Identifying key factors for enhancing dentinogenesis in MSCs is crucial for promoting tooth regeneration. Materials and methods Human dental pulp stem cells (DPSCs) were transfected with retrovirus to obtain SFRP2-over-expressing DPSCs. Alkaline phosphatase (ALP) activity assay, Alizarin red staining, quantitative analysis of calcium, and dentinogenesis-related genes were detected. Additionally, transplantation in a rabbit tooth extraction model was used to explore the role of SFRP2 in dentin regeneration. Results We found SFRP2 over-expression greatly enhanced ALP activity, and mineralization in DPSCs. Real-time RT-PCR revealed SFRP2 over-expression promoted the expressions of OSX, RUNX2, DSPP, DMP1, and BSP. Moreover, Micro CT analysis showed high-density calcification occurred to a much higher extent in SFRP2 over-expressing group compared to control group in vivo. Additionally, HE staining, immmunohistochemistry staining, and scanning electron microscopy results showed much more dentin-like tissue formed in SFRP2 over-expressing group compared to control group. Conclusions Our findings revealed SFRP2 is an important regulator that enhances the dentinogenesis of DPSCs and dentin regeneration in the jaw, which may have clinical applications.

Pleomorphic adenomas (PAs) are the most common benign salivary neoplasms. PAs are generally slow-growing but may sometimes become aggressive and grow rapidly within a short period of time. Here, we report the case of an 83-year-old Chinese woman with an anterior neck mass that had been growing over the past 30 years. She felt uncomfortable because the mass had grown quite rapidly in the past year. The final diagnosis of a PA of the left submandibular gland was confirmed by histopathological and immunohistochemical examinations after surgical resection. Our patient recalled a history of an excision of a neck mass 40 years prior to presentation at another hospital. Based on our imaging findings and surgical findings, we speculate that the neck mass 40 years prior may also have been a PA. Our case reminds us the rare recurrence possibility of PAs, and early and thorough resection may have a good prognosis. In addition, to the best of our knowledge, this is the largest PA of the submandibular gland reported to date.

For the nitrogen oxide removal processes, high performance gas mixer is deeply needed for the injection of NH3 or O3. In this study, a new type of double swirl static mixer in gas mixing was investigated using computational fluid dynamics (CFD). The results obtained using Particle Image Velocimetry (PIV) correlated well with the results obtained from simulation. The comparisons in pressure loss between the experimental results and the simulation results showed that the model was suitable and accurate for the simulation of the static mixer. Optimal process conditions and design were investigated. When L/D equaled 4, coefficient of variation (COV) was

In order to verify the early Paleozoic accretionary assemblage in the Indochina interior and constrain the Prototethyan tectonic evolution in Southeast Asia, this study presents a set of new U-Pb geochronological, elemental, and Sr-Nd-Pb-Hf-O isotopic data for the fifty-two representative granitoids in South Laos. The granitoids from the Kontum terrane, Tam Ky-Phuoc Son tectonic zone, and southern Truong Son igneous zone in South Laos yield the crystallization ages of 464–485 Ma, 455–471 Ma, and 427–446 Ma, respectively, with a northerly younging trend within the Indochina interior. They are mainly monzogranite with A/CNK = 0.96–1.99 and K2O > Na2O, which are marked by enrichment in large-ion lithophile elements and depletion in high field strength elements with remarkable Nb-Ta, Sr-P, and Ti negative anomalies. Their initial 87Sr/86Sr ratios range from 0.70510 to 0.71559, εNd(t) from −9.5 to −3.0, (206Pb/204Pb)i from 18.65 to 19.72, (207Pb/204Pb)i from 15.66 to 15.80, and (208Pb/ 204Pb)i from 38.84 to 39.79. The corresponding zircon ɛHf(t) and δ18O values are in the range of −10.6 to +1.0 and 6.88‰ to 8.94‰, respectively. In addition, their Sr-Nd-Pb and Hf-O isotopic compositions are generally similar with those of time-equivalent granitoids in South Tibet and SW Yunnan, China, and synchronous mafic-intermediate igneous rocks in South Laos, but distinctive from those of the supracrustal sedimentary-derived South China Paleozoic granite and Lincang-Sukhothai S-type granite. The early Paleozoic granitoids in South Laos might have originated from a mixed source of the wedge-derived juvenile crust coupled with supracrustal materials. All these data synthetically suggest the southward subduction of the Tam Ky-Phuoc Son Ocean and the northerly on-growing Ordo-Silurian accretionary orogenesis within the previously defined “single-ancient” Indochina block. The assemblage of the Indochina block might initiate at ca. 430 Ma in the Silurian and terminate in the Early-Middle Devonian.

In Southeast Asia, the Jinshajiang–Ailaoshan suture in Southwest China and the Song Ma zone in Vietnam were generally accepted as the amalgamation boundary of the South China and Simao/Indochina blocks. However, the tectonic location of the Paleotethyan suture in North Laos and its tectonic affinity remain ambiguous. To address this issue, we present the geochemical and geochronological data of a set of mafic and plagiogranitic rocks along the Song Ma suture zone in North Laos. Three groups of rocks with distinctive petrological, geochronological, and geochemical signatures were identified. The ca. 370 Ma Group 1 plagioclase amphibolite was preserved as xenoliths in the ca. 260 Ma granitoids. It exhibits a normal mid–oceanic–ridge basalt (N–MORB)-like, multi-elemental pattern with highly positive εNd(t) (+3.3 to +10.7) and εHf(t) (+6.68 to +7.41) values and low δ18O values (5.3‰−5.5‰), that are interpreted as products of the Late Devonian − earliest Carboniferous continental rift setting. The ca. 270 Ma Group 2 gabbro/diabase–diorite exhibits arc-like geochemical affinity with the εNd(t), εHf(t), and δ18O values of –5.85 to –3.76, –3.8 to +3.2, and 6.6‰–7.6‰, respectively. It is derived from the metasomatized wedge. The ca. 260 Ma Group 3 plagiogranite shows Nb-Ta and Ti negative anomalies and positive εNd(t) (+3.21 to +4.21), εHf(t) (+8.4 to +13.6), and δ18O (5.9‰−6.8‰) values, which are indicative of its derivation from mafic oceanic crust in a subduction setting. In combination with the published data, these results support the development of the Carboniferous–Permian Paleotethyan branch in North Laos, which represents the tectonic location of the Song Ma suture zone that spatially connects the Jinshajiang–Ailaoshan suture zone in Southwest China and the Chenxing–Bangxi suture zone in Hainan Island, South China.

The Cretaceous igneous rocks in the South China Block (SCB) were associated with the slab subduction and roll-back of the Pacific Plate. Thus, they provide excellent opportunities to examine the spatial–temporal geochemical migration of magmatism in the retreating subduction margins. The Cretaceous mafic–intermediate igneous rocks from the southeastern SCB were aged between 142 and 71 Ma, and can geochemically be subdivided into three groups: Group A (126–129 Ma and 83–93 Ma), Group B (126–142 Ma and 71–108 Ma) and Group C (116–142 Ma and 70–110 Ma). Group A and B were mainly distributed in the SCB interior and derived from asthenosphere and asthenosphere–lithosphere interaction sources, respectively. Group C occurred to the east of the Ganjiang Fault and originated from slab–lithosphere interaction. From the coastal provinces to the interior, these mafic–intermediate igneous rocks show increasing incompatible element ratios and Nd isotopic compositions, reflective of a westerly decreasing involvement of slab-derived components. They show two similar age-pulses at c. 125 Ma and c. 90 Ma as well as the Cretaceous A-type granites, indicating two episodes of subduction retreat of the Pacific slab during the Cretaceous. This spatial–temporal pattern of the Cretaceous mafic–intermediate igneous rocks suggests that the Cretaceous slab metasomatism of Pacific subduction retreat was limited to the east of the Ganjiang Fault. Supplementary material: Tables of geochemical data and additional figures are available at https://doi.org/10.6084/m9.figshare.c.4938576

Aim: To explore the roles of exosomal long noncoding RNAs (lncRNAs) in early-stage esophageal squamous cell carcinoma (ESCC) and benign esophagitis. Materials & methods: Exosomal lncRNAs were analyzed using RNA-seq and validated by quantitative real-time PCR, loss-of-function, co-culture and RNA pulldown assays. Results: Exosomal lncRNAs displayed tighter tissue-specificity, higher expression level and lower splicing efficiency than that of mRNAs. A total of 152 exosomal lncRNAs were differentially expressed between ESCC and controls. A total of 124 exosomal lncRNAs were dysregulated between ESCC and esophagitis. Knockdown of 13 ESCC-associated lncRNAs modified proliferation, migration, and apoptosis of ESCC cells. A novel lncRNA RP5-1092A11.2 was highly expressed in ESCC-derived exosomes, ESCC cells and tumor tissues. Exosomes released from RP5-1092A11.2-knockdown cells inhibited ESCC cell proliferation. Conclusion: Dysregulated exosomal lncRNAs were functionally associated with different disease status in esophagus.

Understanding the mechanisms responsible for the interplay between mafic and felsic magmas is the key to retrieving information on their sources, and characterizing the exchange of mass between them. In order to characterize compositional and mineralogical changes in the mafic end-member during mafic-felsic magma interaction and to better understand the nature of early Paleozoic intracontinental magmatism in the South China Block (SCB), a detailed study was conducted on an early Paleozoic hornblendite-quartz monzonite suite in the SCB. The amphibole phenocrysts in the hornblendite are zoned with respect to major and trace elements. From the brown core to the light-green rim, these amphibole phenocrysts display significant increases in Si, Mg, and Mn, coupled with abrupt decreases in Al, Ti, Na, K, and most of the trace elements, but only minor variations in Ca, Fe, Co, and Ni. The light-green matrix amphiboles in the hornblendite have similar compositions to the outer rim of amphibole phenocrysts (except Na). It is important to note that the amphibole grains in the quartz monzonite have significantly higher rare-earth element (REE) contents than the amphibole grains in the hornblendite. There is convincing evidence to support a significant transfer of incompatible elements (e.g., K, Na, LILE, LREE, U, and Th) from the felsic magma to the mafic magma, such as (1) the absence of high-Ca plagioclase in hornblendite, with the majority of feldspar grains being albite (Ab96–97) and orthoclase (Or94–96), and (2) uniform Sr-Nd-Hf isotope compositions (initial 87Sr/86Sr = 0.7081–0.7098; eNd(t) = −6.8 to −6.3; weighted mean zircon eHf(t) = −8.0 to −7.4) for the hornblendite and quartz monzonite samples. It is, therefore, suggested that during mafic-felsic magma interaction, water was transferred from the quartz monzonite magma to the coeval hornblendite magma and promoted the formation of the amphibole crystals in the latter. The incompatible elements transferred from the quartz monzonite magma to the hornblendite magma were mainly incorporated into the late-crystallized anhedral phases in the hornblendite (e.g., orthoclase, sodic plagioclase, quartz, zircon, and apatite). This study suggests that water, which behaves as a supercritical fluid in most mafic-felsic magmas, may play a key role in the exchange of mass between mafic and felsic magmas, and this may be extended to the petrogenesis of biotite-amphibole aggregations in intermediate-felsic magmas.

The South China Block (SCB) consists of the Yangtze and Cathaysia Blocks which, in the northeast, are separated from each other by the Jiangnan Orogen. The southward continuation of the Jiangnan Orogen into the Youjiang Basin remains much debated. Here, we present detailed petrological, chemical and isotope evidence from the Late Jurassic (~159 Ma) Yangtun and Liuliang high-Mg andesites (HMA), eastern Youjiang Basin, to place important constraints on an ancient subduction event. These HMA are enriched in large ion lithophile elements and depleted in Nb-Ta-Ti, with negative whole-rock eNd(t) and zircon eHf(t) values, similar to Neoproterozoic high-Mg rocks that occur in the eastern Yangtze Block. Considering the distance of our study areas to penecontemporaneous Pacific or Tethyan trenches, we infer that these HMA derived from a metasomatised lithospheric mantle preserved beneath the eastern Yangtze Block, which was associated with a Neoproterozoic subduction event. The Late Jurassic HMA in the eastern Youjiang Basin provide potential clues for the southward continuation of the Jiangnan Orogen into the basin.

The volcanic rocks in the Chanthaburi zone are rarely reported, but are important in investigating the tectonic evolution of the Palaeotethyan Ocean in SE Thailand. Four rhyolitic samples from Ko Chang Island yield zircon ages of 258–254 Ma, confirming the presence of Late Permian volcanic rocks in SE Thailand. These rocks consist of Group 1 rhyolites and Group 2 rhyolitic ignimbrites and have high K2O contents of 4.92–7.10 wt% and A/CNK values of 1.10–1.69. They are enriched in the light rare earth elements, Rb, Th, U, Zr and Y and show negative anomalies of Ba, Sr, Nb, Ta and Ti, with clear Eu anomalies. Their whole-rock eNd (t) values range from −1.7 to −3.1. Zircon in situ eHf (t) and δ18O values range from 0.0 to +5.6 and from 8.2 to 9.6‰, respectively. They belong to the group of peraluminous, ultrapotassic A-type rhyolites and were derived from partial melting of a mixed source of Mesoproterozoic metasedimentary rocks with a component of juvenile mafic crust. These ultrapotassic rhyolites formed in a continental rift setting in response to the rollback of a subducted Palaeotethyan oceanic slab beneath the Indochina Block. Combining these results with previous geological observations, we propose that there were some sporadically distributed continental rift basins along the Eastern Palaeotethyan domain during the Permian. Supplementary material: Major oxides, trace element analytical and Nd isotopic data, LA–ICP–MS and SIMS zircon U–Pb ages and Zircon in-situ Hf–O isotopic compositions are available at https://doi.org/10.6084/m9.figshare.c.5635390

Programmed death receptor ligand 1 (PD-L1) is expressed at different levels in tumour tissues and tumour-infiltrating monocytes (TIMCs). The interpretation of PD-L1 expression in gastric cancer (GC) is more difficult because of its heterogeneity.The PD-L1 immunohistochemistry (IHC) by E1L3N assay was performed in GC tissues. The level and distributed characteristics of PD-L1 expression were observed to illustrate its heterogeneity both in the cancer tissues and TIMCs. The relationship between PD-L1 level and necrotic features of tumor cells, the number of TIMCs, the distribution of tertiary lymphoid tissue (TLS) in the stroma, and other clinicopathological factors were analysed. A Cox regression model was used to assess the prognostic value of PD-L1 expression.Of the 110 GC samples, not only more cases (51/110 cases) could be detected by combined positive score (CPS) for PD-L1 expression compared the other two, tumour positive score (TPS), and mononuclear immune-cell density score (MIDS), but also there were more cases with the high level of PD-L1 expression by CPS, even if with good consistency among them (P0.05). The tumour cells with high expression of PD-L1 was prone to show a diffuse distributing, whereas mottled type in the low level. It was noteworthy that the strongly colored tumor cells tended to exhibit a mossy pattern which were distributed along the border between cancer nests and stroma, and the same pattern happened to occur in the positive mesenchymal cells contacting the tumor border, essentially lymphocytes and macrophages. The substantial necrosis in the tumour and the number of TIMCs was analyzed statistically significant correlated with CPS (P0.05), while other clinicopathological factors such as histological type, tumour size, invasion depth, TNM stage were uncorrelated. The number and distribution of TLS in the tumour and para-tumoural stroma indirectly affected PD-L1 in GC by associating with the quantity and pattern of TIMCs. Cox regression analysis revealed that the prognosis was poor when PD-L1 was positive.CPS is the best indicator for PD-L1 expression in GC, which tend to be increased expression following a large number of TIMCs and substantial tumour necrosis appeared. Heterogeneity was reflected in the different distributed pattern of PD-L1 expression, especially the mossy-like pantten of the staining tumor cell in the interface between tumour nests and stroma, regardless of the amount and intensity of PD-L1 expression. TLS is valuable for observing microscopic images to influence the quantity and pattern of TIMCs. CPS can be used as an independent prognostic factor for GC.

The eastern Tibetan Plateau is a key part of the eastern India–Asia collisional zone, a region that records multiple overprinting tectonic and magmatic events. This study presents new geochronological, geochemical, and Sr–Nd–Hf–O isotopic data for Cenozoic potassic granitoids in eastern Tibet, southwestern China, which recorded the tectonic evolution of the eastern Tibetan Plateau. These potassic granitoids are formed between 37.6 and 32.9 Ma and are geochemically subdivided into the following: Group 1, adakite-like granites; Group 2, syenites; and Group 3, low-εNdt granitoids. The Group 1 samples are similar to high-silica adakites in that they have variable SiO2 contents (63.31–73.62 wt.%) and high Sr/Y and La/Yb ratios. These samples have εNdt and εHft values that range from −5.8 to −0.6 and from −4.3 to +5.2, respectively, with δ18O values of 6.78‰–7.36‰. The Group 2 samples are syenites, contain 56.36–63.86 wt.% SiO2 and high concentrations of Y and Yb, and have εNdt values from −8.4 to −2.4, εHft values from −6.1 to +1.1, and δ18O values of 6.37‰–6.89‰. The Group 3 samples have a narrow range of SiO2 concentrations (62.27–64.59 wt.%), high Sr/Y and La/Yb ratios, δ18O values of 6.31‰–6.82‰, and low εNdt and εHft values (−12.6 to −10.9 and −11.4 to −6.6, respectively) that are similar to the values obtained for the contemporaneous Yao’an lamprophyres. These data indicate that the Group 1 samples are formed from magmas sourced from a heterogeneous and thickened region of the lower crust containing an enriched mantle component. Group 2 magmas were most likely derived from contemporaneous mafic melts sourced from an ancient region of the lithospheric mantle previously modified by the incorporation of recycled components. The Group 3 samples have distinct Sr–Nd–Hf isotopic compositions that are indicative of derivation from magmas generated by the fractional crystallization of lower crustal melts sourced from ancient enriched mantle of the Yangtze Block. Combining these new data with the results of previous research suggests that the Cenozoic potassic igneous rocks of eastern Tibet were formed as a result of the thinning of the lithospheric mantle and an associated crustal collapse event, potentially representing a regional late Eocene to early Oligocene transition from compression to transtension in the eastern Tibetan Plateau. These potassic igneous rocks are contemporaneous with or are younger than igneous rocks in the Qiangtang Block, suggesting that the magmatic response to the India–Asia collisional event was initiated in the central Tibetan Plateau before propagating towards the eastern margin of this region.

The most striking structural features in the interior of the Shan Plateau, southeast of the eastern Himalayan syntaxis, are a series of NE-trending faults that exhibit sinistral movement and an arcuate geometry. Their origin and tectonic evolution remain poorly understood. Furthermore, a switch in slip sense is recorded along many of these faults, but the timing of kinematic reversal is still unclear, hindering an understanding of the causal geodynamic mechanisms. We conducted an integrative study of apatite and zircon (U-Th)/He thermochronology, 40Ar/39Ar geochronology, and structural and geomorphic analysis to decipher the evolution of two major NE-trending faults: the Nantinghe and Dayingjiang faults. At least three deformation stages are identified within the Nantinghe fault zone, including top-to-the-SE/ESE thrusting, dextral ductile strike-slip shearing, and sinistral movement. Zircon and apatite (U-Th)/He data, collected from the northeastern terminus of the Nantinghe fault, reveal rapid cooling in the early Miocene. Combined with the 40Ar/39Ar data from sinistrally sheared mylonite, left-lateral movement on the Nantinghe fault is inferred to have initiated as early as ca. 20 Ma. The Dayingjiang fault reactivated as a sinistral brittle fault along the dextral Yingjiang shear zone. A two-stage thermal history is identified along the shear zone, with prominent cooling during dextral ductile shearing in the early- to mid-Miocene followed by a lower-magnitude cooling episode at ca. 11 Ma caused by sinistral transtension along the Dayingjiang fault. The evolution of the Nantinghe and Dayingjiang faults suggests that the NE-trending fault system in the Shan Plateau may have developed along preexisting structures and underwent diachronous slip-sense inversion in the late Cenozoic. The northward advance of the eastern Himalayan syntaxis caused a major change in both the regional stress field and fault geometries in the eastern India-Eurasia oblique convergence zone, contributing to the inversion of fault kinematics.

To better reveal the tectonic process of the Jiangnan Orogen in creating the united South China Block (SCB), a set of new geochronological, geochemical, and Sr-Nd-Hf-O isotopic data is herein presented for the coeval early Neoproterozoic mafic to acid rocks in the Lengjiaxi Group and its equivalents. Our data show that these rocks belong to subalkaline basalt, basaltic andesite, andesite, and dacite in composition, and can be geochemically classified into N-MORB- and arc-like mafic (Group 1 and Group 2, respectively), along with high-Mg andesitic-dacitic (Group 3) rocks. They yield zircon U-Pb ages of 837 ± 4 Ma, 832 ± 11 Ma, and 835 ± 7 Ma, respectively, suggesting their early Neoproterozoic (ca. 835 Ma) origin. Group 1 has SiO2 = 47.21–52.45 wt%, MgO = 7.36–10.07 wt% with Mg-number of 56–68, 87Sr/86Sr(t) = 0.7062–0.7136 and εNd(t) = +1.3–+9.4, along with N-MORB-like REE- (rare earth element) and PM (primitive mantle)-normalized patterns, suggesting its derivation from a refractory MORB-like source newly introduced by slab-derived fluid. The Group 2 samples are classified as tholeiitic basalt and basaltic andesite with SiO2 = 48.78–55.75 wt%, MgO = 7.70–12.74 wt%, Mg-number = 63–77, 87Sr/86Sr(t) = 0.7046–0.7098 and εNd(t) = –1.6 to –0.4. They exhibit similar “spiky” REE- and PM-normalized patterns to typical arc basalt, with pronounced enrichment in (large ion lithophile elements) and sharp depletion in (high field strength elements), probably inheriting from a sub-arc source modified by fluids and/or melts released from recycled sedimentary component. The Group 3 rocks show SiO2 = 57.74–66.30 wt%, FeOt = 6.22–8.59 wt%, Mg-number = 43–66, K2O+Na2O = 3.18–6.17 wt% with K2O/Na2O of 0.59–3.28, classified as high-Mg andesites and dacites. Diagnostic elemental and isotopic ratios of Group 3 include (La/Yb)cn = 7.7–11.4, (Gd/Yb)cn = 1.44–1.87, Eu/Eu* = 0.49–0.80, Nb/La = 0.27–0.42 and εNd(t) = –7.3 to –5.4, resembling to those of other early Neoproterozoic high-Mg intermediate rocks in the SCB, originating from a mantle wedge source with proportional addition of the recycled SCB sediment-derived components. In combination with the available data and geological observations, it is concluded that the N-MORB- and arc-like mafic, along with high-Mg andesitic rocks are coeval in the Lengjiaxi Group and its equivalents along the central Jiangnan Orogen and formed at ca. 847–832 Ma of the early Neoproterozoic period. The synthesis of these observations suggests the development of an early Neoproterozoic continental arc-basin setting. The arc-basin system westerly subducted and finally closed at ca. 830 Ma and the assembly of the Yangtze and Cathaysia blocks terminated at ca. 810 Ma along the central Jiangnan Orogen.

The Mesoproterozoic Baoban Complex, southwest Hainan Island, has played a crucial role in deciphering Nuna (Columbia) supercontinent reconstructions. Metasedimentary rocks in the Baoban Complex are intruded by Mesoproterozoic gneissic granites and mafic rocks. Our new geochemical and geochronological data show that these gneissic granites are monzogranites and granodiorites and crystallized at ∼1430 Ma. Geochemically, they are subdivided into two groups with I- and A-type affinities. The groups show broadly similar eNd (t) values ranging from −2.4 to +0.9, zircon eHf (t) from −5.4 to +7.8 and δ18O values from +5.0 to +8.6‰, suggesting derivation from the same source involving juvenile mafic melt and ‘‘ancient” continental crust components. Metasedimentary rocks have high La/Sc (1.4–5.8) but low Sc/Th (0.6–1.6) and Co/Th (0.3–1.1) ratios, as well as negative eNd (t) of −4.5 to −4.1, indicative of an “ancient” felsic igneous source with a recycled sedimentary component. Detrital zircon grains from the metasedimentary rocks yield three primary age-peaks of ∼1780 Ma, ∼1610 Ma and ∼1440 Ma, with the depositional age synchronous with those of the gneissic granites and metabasites (∼1430 Ma). Our geochemical and geochronological data, along with regional geological constraints, suggest a rift setting. The age populations and hafnium compositions of detrital zircons from the metasedimentary rocks in the Baoban Complex, southwest Hainan are comparable to those igneous zircons from East Antarctica, pointing out a probable affinity between southwest Hainan and East Antarctica in the Nuna supercontinent.

New geochronological, geochemical and Sr-Nd-Hf isotopic data for the early Cretaceous Daying volcanic sequence, eastern Qinling Orogen, provides a probe into the nature of, and tectonic process operating in, the underlying Mesozoic mantle. The volcanic rocks in the sequence are composed of basaltic trachyandesite, pyroxene-andesite, trachyandesite and trachyte. They yield zircon U-Pb and whole-rock 40Ar/39Ar plateau ages of 134–124 Ma, roughly synchronous with the Cretaceous igneous rocks throughout the eastern Qinling and Dabie orogens. Clinopyroxene and plagioclase phenocrysts of the volcanic rocks exhibit simple normal zonation with higher mg-number and An content in the core relative to the rim. The amphibole is characterized by tschermakite and tschermakitic hornblende with mg-number of 50–67. The Daying volcanic rocks have variable SiO2 (54.27–63.44 wt%), Al2O3 (15.39–20.34 wt%), FeOt (5.23–9.94 wt%), and MgO (1.05–4.03 wt%) contents with low mg-number (26–49). They exhibit arc-like REE- and PM-normalized patterns with significant negative Nb-Ta anomalies, and highly- enriched Sr-Nd isotopic composition with (87Sr/86Sr)i ratios of 0.7066–0.7078 and eNd(t) values of −15.5 ∼ −11.0. Their zircons exhibit strongly negative eHf(t) values ranging from −27.3 to −17.2 and two-staged model ages from 2.90 Ga to 2.28 Ga. Such geochemical signatures suggest that the Daying volcanic rocks were derived from a hybridized source of the North China Craton enriched mantle with the input of some Yangtze crustal materials created by Triassic deep-subduction digestion. They also share similar eruption time, as well as elemental and Sr-Nd-Hf isotopic compositions, with those in the southern margin of the North China Craton, suggesting a northward subduction of the Yangtze block. It is proposed that the volcanic rocks are petrogenetically related to an early Cretaceous extensional event along the Qinling- Dabie Orogenic belt in response to unrooting of the thickened lithosphere.

The NE–SW-trending Qin-Hang Belt and east–west-trending Nanling Range are two critical magmatic and mineralization zones in the southeastern South China Block (SCB). However, the formation timing and petrogenesis of the magmatism in these zones, along with the relationship with the Pacific subduction, remain hotly debated. Herein, this study presents a set of zircon U–Pb geochronological, Lu–Hf isotopic and whole-rock geochemical data for the Late Jurassic Mashan and Nandu shoshonitic intrusions in the Qin-Hang Belt. All the samples are enriched in large ion lithophile elements and light rare earth elements. They have high eNd(t) (from −1.4 to +4.4) and zircon eHf(t) values (from −1.0 to +3.4) and low initial 87Sr/86Sr (0.70426–0.70696), distinct from those of the Triassic shoshonitic rocks but comparable with those of the Jurassic shoshonitic rocks in the region. Such signatures suggest that the Mashan and Nandu igneous rocks mainly derived from a Jurassic metasomatized lithospheric mantle in response to asthenospheric upwelling, without significant contribution from subducted slab-derived components. Our new data, together with other geological observations, reveal a spatial change of magmatic activities, structural patterns, sedimentary basins and palaeocurrent directions during the Middle–Late Jurassic, probably associated with the far-field effects of the Pacific subduction in the interior SCB.

Felsic igneous rocks in northern Laos are key elements of the Truong Son and Song Ma tectonic zones and are important for constraining the Paleotethyan evolution in southeastern Asia. This paper presents new geochronological, geochemical and Sr–Nd–Hf–O isotopic data from granitoids and rhyolites in northern Laos. Geochronological data show that these samples have zircon U-Pb ages ranging from ca. 281 Ma to 221 Ma. These samples can be subdivided into four groups based on their lithology and geochemical composition. Group 1 samples are granodiorite and granite with I-type geochemical characteristics. They have lower 87Sr/86Sr (i) ratios (0.7036–0.7059) and higher eNd (t) values (+0.7 − +0.8) than Group 2 biotite granite samples (87Sr/86Sr (i) = 0.7087–0.7129 and eNd (t) = −5.3 to −9.2) and Group 3 rhyolite samples (87Sr/86Sr (i) = 0.7092–0.7103 and eNd (t) = −5.9 to −8.9). Zircon grains from Group 1 samples yield positive eHf (t) values of +5.1 − +13.8, TDM ages of 0.37–0.71 Ga and δ18O values of 5.6–6.3‰. In contrast, zircons from Group 2 and Group 3 samples have mainly negative eHf (t) values (−9.6 to +1.6 and −4.7 to −14.7), older TDM ages (1.08–1.70 Ga and 1.42–1.97 Ga), and higher δ18O values (5.7–10.3‰ and 6.7–8.0‰), respectively. Our geochemical data suggest that the Group 1 granite samples are the products of the partial melting of newly underplated mafic rocks, whereas the Group 2 and 3 samples originated from a mixed source of “ancient” metaigneous and metagreywacke components. Group 4 samples include Late Triassic I-type granodiorite and granite and have eNd (t) = −1.9 to −3.9, 87Sr/86Sr (i) = 0.7079–0.7084, zircon eHf (t) = 0.0 − +7.5, and δ18O = 5.1–6.9‰, indicating a derivation from a metagreywacke source with a component of juvenile mafic crust. Our data suggest that the Permian felsic igneous rocks in northern Laos formed in an arc setting related to the Song Ma Paleotethyan branch/BAB subduction, whereas the Late Triassic I-type granitoids formed in a post-collisional setting in response to the gravitational collapse of thickened crust during the collision of the South China and Indochina blocks. The temporal-spatial pattern of igneous rocks along the Truong Son zone is related to the Paleotethyan evolution and resembles that along the Ailaoshan-Song Ma zone and its eastward extension in northern Hainan.

Whether the driver of the Indosinian orogeny in the South China block was related to the evolution of the Paleotethyan Ocean or the Paleo-Pacific Ocean has been a point of much debate. We applied detrital zircon U-Pb dating to Permian–Triassic sedimentary rocks from South China to trace sediment provenance and to further test these models. Our results, combined with other published data from the Pingxiang, Youjiang, Yong’an, and Yongding Basins, show that 400–350 Ma and 300–260 Ma zircon grains are ubiquitous throughout the entirety of southern South China. This indicates regional magmatic events as potential sources. The discovery of Middle–Late Devonian and Early Permian igneous rocks, tuffs, and volcaniclastic rocks in Southeast Asia and Hainan Island implies the presence of two magmatic events (400–350 Ma and 300–260 Ma) within or beyond the southern margin of South China. This information, together with the mostly negative εHf(t) values of 400–350 Ma and 300–260 Ma zircon grains, arc-like geochemical signatures of the possible source rocks, and the regional geology of East Asia, suggests that they originated from sources related to Paleotethyan and even Proto-Tethyan subduction. Thus, Permian–Triassic sedimentation and the Indosinian orogeny in South China were largely controlled by the evolution of the Tethyan Ocean.

High-speed transportation is closely related to people’s livelihood and national economy, so it becomes an important development aspect to the whole country. The safety, comfort and economy of high-speed train are the key consideration during its design process. In the future, new trains and old ones will be used for a long time, and the performance of new trains which run on the old lines may be limited. These situations make the research of high-speed train with asymmetric heads much necessary. Aiming at the feasibility of the train with asymmetric heads, the heads of train CRH3 and another typical train with a similar speed are selected. Based on the two heads, the digital models of the traditional trains with symmetric heads and the new trains with asymmetric heads are built firstly. And then their aerodynamic characteristics are computed by the SIMPLE method. In the numerical part, the performances of the trains are compared on the condition without crosswind, which shows that one of the new trains with asymmetric heads is the best among them. Moreover, the aerodynamic characteristics of this new model under crosswind is analyzed, which demonstrates that the train with asymmetric heads is feasible. The research shows that the train with asymmetric heads can achieve better results through the proper aerodynamic shape optimization design, which presents an idea for the future high-speed train design.