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Knowledge graphs as external information has become one of the mainstream directions of current recommendation systems. Various knowledge-graph-representation methods have been proposed to promote the development of knowledge graphs in related fields. Knowledge-graph-embedding methods can learn entity information and complex relationships between the entities in knowledge graphs. Furthermore, recently proposed graph neural networks can learn higher-order representations of entities and relationships in knowledge graphs. Therefore, the complete presentation in the knowledge graph enriches the item information and alleviates the cold start of the recommendation process and too-sparse data. However, the knowledge graph's entire entity and relation representation in personalized recommendation tasks will introduce unnecessary noise information for different users. To learn the entity-relationship presentation in the knowledge graph while effectively removing noise information, we innovatively propose a model named k n o w l e d g e — e n h a n c e d   h i e r a r c h i c a l   g r a p h   c a p s u l e   n e t w o r k (KHGCN), which can extract node embeddings in graphs while learning the hierarchical structure of graphs. Our model eliminates noisy entities and relationship representations in the knowledge graph by the entity disentangling for the recommendation and introduces the attentive mechanism to strengthen the knowledge-graph aggregation. Our model learns the presentation of entity relationships by an original graph capsule network. The capsule neural networks represent the structured information between the entities more completely. We validate the proposed model on real-world datasets, and the validation results demonstrate the model's effectiveness. [ABSTRACT FROM AUTHOR]

Aluminum matrix composites reinforced with 10 vol.% SiC particles (SiCp/Al MMCs) were prepared throughthe vacuum stirring method from SiC particles preoxidated at high temperature, followed by posttreatments of remelting and Sc addition treatment. Major problems during vacuum stirring preparation were investigated. Results show that overoxidation of SiC particles may occur during the vacuum stirring process, which causes loss of SiC particles and increases in "impurity pores" after solidification or aggregation of SiC particles, leading to scarcely improved mechanical properties of the prepared SiCp/Al composites. After Sc addition treatment, the α-Al and eutectic Si phases were obviously refined. The composite matrix was strengthened. The result indicates that the maximum tensile strength of 10 vol.% SiCp/A356 composites with Sc addition treatment was 193.5 MPa, which was increased by 43% compared with the matrix alloy. Moreover, a fracture at particles was detected after Sc addition treatment. The stress could be effectively transferred to the SiC particles when the fracture occurred. [ABSTRACT FROM AUTHOR]

Lung cancer is the highest incidence and mortality of all cancers around the world. In the present immunotherapy era, an increasing number of immunotherapeutic agents including monoclonal antibody‐targeted drugs have been used in the clinical treatment of malignancy, but it still has many limitations. Chimeric antigen receptor‐modified T (CAR‐T) cells, a novel adoptive immunotherapy strategy, have not only been used successfully against hematological tumors, but have also opened up new avenues for immunotherapy of solid tumors, including lung cancer. However, targeting lung cancer‐specific antigens using engineered CAR‐T cells is complicated by the lack of proper tumor‐specific antigens, an immunosuppressive tumor microenvironment, a low level of CAR‐T cell infiltration into tumor tissues, along with off‐target effect, etc. Simultaneously, the clinical application of CAR‐T cells remains limited because of many challenges such as tumor lysis syndrome, neurotoxicity syndrome, and cytokine release syndrome. In this review, we outline the basic structure and generation characteristic of CAR‐T cells and summarize the common tumor‐associated antigens in clinical trials of CAR‐T cell therapy for lung cancer, and point out the current challenges and new strategies, aiming to provide new ideas and approaches for the pre‐clinical experiments and clinical trials of CAR‐T cell therapy in lung cancer. [ABSTRACT FROM AUTHOR]

A vast amount of evidence indicates that long non-coding RNAs (lncRNAs) are involved in cancer. Previous studies have indicated that lncRNA DiGeorge syndrome critical region gene 5 (DGCR5) is aberrantly expressed in lung cancer, pancreatic ductal adenocarcinoma and hepatocellular carcinoma. However, the role of DGCR5 in papillary thyroid carcinoma (PTC) has remained elusive. In the present study, it was revealed that DGCR5 was significantly downregulated in PTC tissues compared with that in adjacent normal tissues. Through functional experiments, it was demonstrated that ectopic overexpression of DGCR5 markedly suppressed PTC cell growth and invasion. A bioinformatics analysis suggested that DGCR5 binds to microRNA (miR)-2861. A total of 5 putative binding sites for miR-2861 were identified in DGCR5, and a luciferase reporter assay confirmed the direct interaction between DGCR5 and miR-2861. Furthermore, reverse transcription-quantitative polymerase chain reaction analysis indicated that ectopic overexpression of DGCR5 led to a decreased expression of miR-2861 in PTC cells and miR-2861 mimic transfection caused a downregulation of DGCR5. miR-2861 level was upregulated in PTC tissues compared with adjacent tissues and negatively correlated with DGCR5 level. In addition, rescue experiments indicated that ectopic expression of miR-2861 reversed the effects of DGCR5 overexpression on PTC cell proliferation and invasion. Taken together, the present results demonstrated that DGCR5 inhibits PTC progression via sponging miR-2861, indicating DGCR5 may serve as a therapeutic target. [ABSTRACT FROM AUTHOR]

Objective: To identify the significantly altered circRNAs and mRNAs in thyroid cancer, investigate their target miRNAs and determine their biological functions. Methods: The differentially expressed circRNAs, mRNAs and pathways in thyroid cancer were identified by microarray analysis and gene set enrichment analysis (GSEA). The correlative circRNAs and mRNAs were found out through Pearson correlative analysis. The common target miRNAs of circNEK6 and FZD8 related to thyroid cancer was screened out through Targetscan, miRanda and HMDD analysis. The mRNA and protein expressions in thyroid cancer tissues and cells were detected by qRT-PCR and western blot. CircRNA was confirmed by the RNase R digestion and nucleic acid electrophoresis. The target relationships were verified by the dual luciferase reporter assay. Cell viability, invasion and apoptosis were determined by MTT assay, Transwell assay and flow cytometry, respectively. Results: CircNEK6 and FZD8 were significantly up-regulated in thyroid cancer, with strong correlations. The Wnt signaling pathway was activated in thyroid cancer. MiR-370-3p was the common target miRNA of circNEK6 and FZD8, and it was down-regulated in thyroid cancer. Overexpression of circNEK6 and FZD8 could promote the growth and invasion of thyroid cancer cells, while up-regulation of miR-370-3p could suppress thyroid cancer progression and inhibit the Wnt signaling pathway. MiR-370-3p's effect on thyroid cancer cells could be rescued by circNEK6 or FZD8. Conclusion: CircNEK6 promoted the progression of thyroid cancer through up-regulating FZD8 and activating Wnt signaling pathway by targeting miR-370-3p. [ABSTRACT FROM AUTHOR]

Thyroid carcinoma is primarily treated by surgery combined with radioactive 131iodine (131I) treatment; however, certain patients exhibit resistance to 131I treatment. Previous research indicated that nuclear factor‑κB (NF‑κB) was associated with resistance to 131I in cancer cells. The present study aimed to investigate the effects of NF‑κB on 131I uptake and apoptosis in thyroid carcinoma cells. TPC‑1 and BCPAP cell lines were employed as research models in the present study, and the expression of NF‑κB was inhibited by RNA interference (RNAi). The ability of TPC‑1 and BCPAP cells to uptake 131I was measured and the cell viability was detected by an MTT assay. Finally, the expression of the apoptosis‑associated proteins X‑linked inhibitor of apoptosis (XIAP), cellular inhibitor of apoptosis protein 1 (cIAP1) and caspase‑3 in TCP‑1 and BCPAP cells was determined by western blotting. Western blotting results demonstrated that the expression levels of NF‑κB in TPC‑1 and BCPAP cells were successfully downregulated by RNAi (P<0.05), while analysis of 131I uptake revealed no significant alterations in the 131I uptake ability of cells following RNAi (P>0.05). MTT experiments demonstrated that the inhibition of NF‑κB expression in combination with radiation (131I treatment) led to a marked reduction in cell viability (P<0.05). Furthermore, western blot analysis revealed that the inhibition of NF‑κB expression downregulated the expression levels of XIAP and cIAP1 (P<0.05), while the expression levels of caspase‑3 were upregulated, indicating that the observed reduction in cell viability following NF‑κB inhibition may be due to an increased level of apoptosis. Although NF‑κB inhibition did not affect the 131I uptake of thyroid cancer cells, this inhibition may increase the apoptotic effects of radioactive 131I. [ABSTRACT FROM AUTHOR]

At present, reliable and precise ship detection in high-resolution optical remote sensing images affected by wave clutter, thin clouds, and islands under complex sea conditions is still challenging. At the same time, object detection algorithms in satellite remote sensing images are challenged by color, aspect ratio, complex background, and angle variability. Even the results obtained based on the latest convolutional neural network (CNN) method are not satisfactory. In order to obtain more accurate ship detection results, this paper proposes a remote sensing image ship object detection method based on a brainlike visual attention mechanism. We refer to the robust expression mode of the human brain, design a vector field filter with active rotation capability, and explicitly encode the direction information of the remote sensing object in the neural network. The progressive enhancement learning model guided by the visual attention mechanism is used to dynamically solve the problem, and the object can be discovered and detected through time–space information. To verify the effectiveness of the proposed method, a remote sensing ship object detection data set is established, and the proposed method is compared with other state-of-the-art methods on the established data set. Experiments show that the object detection accuracy of this method and the ability to capture image details have been improved. Compared with other models, the average intersection rate of the joint is 80.12%, which shows a clear advantage. The proposed method is fast enough to meet the needs of ship detection in remote sensing images. [ABSTRACT FROM AUTHOR]

Abstract: The Sm–Nd isotopic system, one of the important techniques for dating and geochemical tracing, has been widely used in geosciences. Precise and accurate measurements of Nd isotopic ratios are more difficult to achieve for microsamples that contain less than 50ngNd, when routine Nd+ technique is applied on thermal ionization mass spectrometer (TIMS). Compared to Nd+ technique, the NdO+ technique, owing to more efficient ionization, is a better choice for high precision measurements of Nd isotopic ratios of micro- or low-content samples. This study presents measurement results of sub-nanogram size samples of standard reference solution and rock-powder using NdO+ technique on the latest TIMS (GV product IsoProbe-T). Sixteen rock-powder references and four reference solutions were measured both by NdO+ and Nd+ techniques for an evaluation of accuracy and precision of measurements obtained by the NdO+ technique. Results show that analytical precision and reproducibility of NdO+ measurements of sub-nanogram Nd is comparable with those obtained by the Nd+ measurements of samples containing 200ngNd. Internal precision of the 143Nd/144Nd ratios achieved with both techniques is better than 0.003%. Our results show that the microsample NdO+ technique is a very promising method for high resolution Sm–Nd geochronology and isotopic tracing. [Copyright &y& Elsevier]

The Moldanubian zone of the Black Forest, Germany, part of the internal zone of the central European Variscan belt, exposes high-pressure metamorphic rocks as small eclogite lenses in host gneisses. We report zircon U-Pb and PbPb ages and garnet Sm-Nd and Pb-Pb ages for five eclogites. The less mobile trace element contents of these eclogites are similar to those of mid-ocean ridge basalts but have moderate to highly fractionated concentrations of the rare earth elements, enrichments in the incompatible elements, and negative anomalies in the high-field strength elements. Initial ∈[sub Nd] values range from -3 to +1.8, and initial[sup 87]Sr/[sup 86]Sr ratios range from 0.7040 to 0.7062. These characteristics of the eclogites suggest an origin from mantle-derived magmas contaminated either by evolved crustal material during intrusion or altered by fluid before or during eclogitization. A combination of zircon U-Pb and Pb-Pb evaporation dates of the eclogites constrains a magmatic episode between ∼486 and ∼445 Ma. This episode was contemporary with the early Paleozoic mafic to ultramafic magmatism in the eastern part of the Variscan belt and probably represents an early Paleozoic rift-stage product. Garnets subjected to the stepwise acid-leaching method from three eclogites yield Sm-Nd isochron ages of about 348-340 Ma, similar to the dates previously reported. The same garnets give less precise Devonian to Early Carboniferous Pb-Pb isochron ages of 406 ± 31 Ma, 386 ± 21 Ma, and 353 ± 89 Ma, which probably date to an earlier stage of the Variscan convergence. [ABSTRACT FROM AUTHOR]

Granitic rocks forming in the syn- to post-orogenic stages can trace the compositional and structural complexity of the crust beneath an orogenic belt. The Qinling orogenic belt undertook multiple stages of tectonics and magmatism, resulting in the multifaceted evolution and compositional diversity of the crust. In the present study, the Guangtoushan and Miba plutons in South Qinling were chosen to reveal the crustal heterogeneity in study area via isotopic geochemistry and zircon geochronology. The Guangtoushan pluton was emplaced between ~215 Ma and ~202 Ma and the Miba pluton formed at ~213 Ma, as constrained by zircon U-Pb isotopic dating. Granitic rocks of the Miba pluton are characterized by amphibole bearing and homogeneous composition, with relatively depleted Sr-Nd isotopic compositions (initial 87Sr/86Sr values of 0.7060 to 0.7084 and initial εNd values of −5.4 to −9.5) and high Pb isotopic values. The Guangtoushan pluton contains muscovite and complex inherited zircon grains and has variable Sr-Nd isotopic composition (initial 87Sr/86Sr values of 0.7050 to 0.7091 and initial εNd values of −4.5 to −12.9) and low Pb isotopic values. Felsic magmas of the Guangtoushan pluton should be derived mainly from meta-sedimentary rocks beneath South Qinling, while the Miba pluton originated primarily from partial melting of meta-igneous rocks. The compositional diversity recorded in the Early Mesozoic plutons was caused by the heterogeneous crust, and partial melting was induced by heating of the up-welling asthenosphere in a post-collision setting. [ABSTRACT FROM AUTHOR]

The phenomenon of DNA phosphorothioation (DNA sulfur modification) is widespread among prokaryotes and may serve as a mechanism to restrict gene transfer among bacteria. DndE is one of five essential proteins that are required for the DNA phosphorothioation process. However, its exact biochemical role in sulfur modification of DNA remains unclear. In this study, the DndE protein homologue from Salmonella enterica serovar Cerro 87 was overexpressed, purified and crystallized. The crystals of the DndE protein diffracted to 2.7 Å resolution and belonged to space group P3121. These results will facilitate detailed structural analysis of DndE and further elucidation of its biochemical function. [ABSTRACT FROM AUTHOR]

An increasing number of functional studies shows that long noncoding RNAs (lncRNAs) are involved in many aspects of cellular physiology and fulfills a wide variety of regulatory roles at almost every stage of gene expression. A major feature of lncRNAs is the highly folded modular domains in transcripts. With improved modeling and definition, it is now feasible to explore and gain novel insights into the structural–functional relationship of lncRNAs and their association with complex human diseases. In this study, we utilized an automatic computational pipeline to scan lncRNA architecture at the genome-wide scale and to obtain a landscape of functional domains. An accurate alignment algorithm was performed to identify 40 triple pairs between single-nucleotide polymorphisms (SNPs), lncRNAs and diseases. In order to detect the potential contribution of a lncRNA's modular character, we estimated and evaluated structural rearrangements, which were derived from disease-associated SNPs. In addition, we focused on annotating and comparing the global and local heterogeneity of the wild-type and mutant lncRNAs. Assessing lncRNA architecture has yielded how variations in structured regions impact the molecular mechanisms of lncRNAs and how SNPs disturb binding and recruiting ability. These observations are the first glimpse of the 'lncRNA structurome' and make it possible to robustly explore and assemble intricate space conformation and their stress variation. This result also successfully demonstrates that lncRNA transcripts contain a complex structural landscape and highlights the proposed contribution of lncRNA structure in controlling RNA functions and disease mechanisms. [ABSTRACT FROM AUTHOR]

Sediments or clastic rocks can record the evolution history of basins, orogenic processes, crustal uplift and erosion, and even paleo-environments. Detrital minerals such as zircon, garnet, and apatite are useful media for studies of sedimentary sources and basin evolution. Detrital zircon has been widely taken as an indicator for provenances and tectonic evolution of geological terrenes via age distribution patterns. Apatite can remain stable during erosion and transportation and is also considered as an ideal object for source tracing. This mineral normally contains high Sr and negligible Rb. Its Sr isotopic composition can remain almost unchanged after crystallization. Unlike isotopic ages of detrital minerals, Apatite isotopic compositions have been less frequently used for tracing the provenance of sedimentary rocks in the last few decades. In the present study, we report on the Sr isotopic composition of individual apatite grains of Neogene and Jurassic conglomerates from the Hui-Cheng basin in the South Qinling orogenic belt, obtained via thermal ionization mass spectrometry. Detrital apatite grains of Jurassic rocks have narrow ranges of 87Sr/86Sr values from 0.7076 to 0.7100, but those of Neogene rocks gave variant 87Sr/86Sr values from 0.7055 to 0.7534, providing distinct evidence for complex sources of Neogene sedimentary rocks. Analytical results show that the distribution patterns of 87Sr/86Sr values of single-grain detrital apatite fit the distribution patterns of detrital zircon U-Pb from the isotopic ages very well. Detrital apatite Sr isotopic composition can provide essential information for tracing the origins and evolution of sedimentary sources. [ABSTRACT FROM AUTHOR]

Disulfidptosis is a newly discovered form of cell death. Not yet clearly classified as programmed cell death or accidental cell death. This study aimed to create a novel disulfidptosis-related lncRNA index (DLI) that can be used to predict survival and chemotherapy drugs sensitivity in patients with cervical cancer. First of all, we found lncRNAs associated with disulfidptosis between cervical cancer tissues and normal tissues. By LASSO-Cox analysis, overlapping lncRNAs were then used to construct lncRNA index associated with disulfidptosis, which can be served to predict the prognosis of patients with CC, especially the chemotherapy drugs sensitivity. ROC curves and PCA based on DLI and clinical signatures were developed and demonstrated to have good predictive potential. In addition, differences in immune cell subset infiltration and differences in immune checkpoint expression between high-DLI and low-DLI groups were analyzed, and we investigated the relationship between the DLI and tumor mutation burden (TMB). In summary, we constructed a lncRNA prediction index associated with disulfidptosis. This has important clinical implications, including improving the predictive value of cervical cancer patients and providing a biomarker for cervical cancer guiding individualized treatment. [ABSTRACT FROM AUTHOR]

The Yangtze Block records Neoproterozoic magmatism and sedimentation related to the breakup of Rodinia and is an important piece in the reconstruction of the supercontinent. However, the tectonic setting and position of this block in Rodinia remain a subject of debate. In the present study, we report the zircon U-Pb ages and Hf isotopic composition of zircon and geochemical and Nd-Pb isotopic compositions for meta-volcanic rocks exposed in the Zhangbaling uplift of the NE Yangtze Block. The volcanic rocks, dominated by rhyolite and dacite, belong to the calc-alkaline series and show geochemical characteristics of arc rocks. Zircon U-Pb isotopic ages show that volcanic rocks in the Xileng Formation formed at ca. 790 Ma and ca. 760–700 Ma peaking at ~740 Ma. The late-stage volcanism was widely exposed in the uplift, characterized by a temporal-spatial trend becoming younger southwards. The old volcanic rocks have low initial εNd (−11.0) and εHf (−19.7 to −8.2) values and low Pb isotopic ratios, likely indicating an origin from ancient basement rocks underneath the Yangtze Block. The younger ones, being similar to continental arc andesite in trace element compositions, have relatively high initial εNd (mostly −4.6 to 0.5) and εHf (−0.4 to 8.8) values and high Pb isotopic ratios. These isotopic features point to an origin from the partial melting of juvenile crustal rocks. Sedimentary rocks of the Xileng Formation and the overlying strata also contain numerous zircon grains of ~700 Ma to ~630 Ma. The volcanic rocks in the Zhangbaling uplift might demonstrate long-lasting subduction along the northeastern margin of the Yangtze Block, probably active until ca. 700 Ma. [ABSTRACT FROM AUTHOR]

Detrital zircon of clastic rocks has been widely recognized as a powerful tool for the study of crustal uplift, which is of great significance for understanding multi-sphere interaction. However, young detrital zircons can only roughly constrain the depositional time of the strata, and commonly used zircon age probability density and kernel density estimations cannot provide sufficient evidence to reveal spatio-temporal differences in tectonic uplift. The basins developed in active continental margins usually contain abundant magmatic rocks, which can provide insights into basin evolution and crustal deformation when combined with sedimentary characteristics. In this study, we report detrital zircon ages of Late Mesozoic clastic rocks from the Boli Basin, being part of the Great Sanjiang Basin Group in eastern NE China, which is strongly affected by the Paleo-Pacific subduction. In conjunction with the age data of coeval magmatic rocks and potential sedimentary sources of basement rocks adjacent to the basin, the geochronologic results of this study provide solid evidence for the formation of the Boli Basin and the spatio-temporal evolution of the crustal uplift in northeastern China. The Boli Basin went through multi-phase tectonic evolution of syn-rift and post-rift stages, based on the zircon age data of clastic and igneous rocks. When the geographical distribution characteristics of potential sedimentary sources and their percentages of contribution are taken into account, two stages of eastward migration of the crustal uplift and two episodes of basin destruction caused by the tectonic extension and subsequent compression can be proposed for the Boli Basin. These processes were caused successively by the rolling back of the subducted Paleo-Pacific slab, the docking of the Okhotomorsk block along the eastern continental margin of East Asia, and the transition of the subduction zone by the collision of the Okhotomorsk block. [ABSTRACT FROM AUTHOR]

The Ghohroud granitoids (GG), containing mafic microgranular enclaves (MMEs) are located in the central part of the Urumieh‐Dokhtar Magmatic Arc (UDMA) in central Iran. They are associated with the subduction‐related magmatism in the Alpine‐Himalayan orogenic belt. The GG are comprised of a variety of intermediate and felsic rocks, including tonalite, granodiorite, granite, diorite porphyry and monzodiorite. The MMEs are gabbroic diorite and tonalite in composition and characterized by a fine‐grained hypidiomorphic microgranular texture with occasional chilled margins. They show rounded, sharp or irregular contact with the host granitoids. The occurrences of quartz, K‐feldspar and corroded plagioclase indicate that MMEs are the products of mixing between mantle and crust‐derived magmas. New ages of zircon U–Pb dating reveal that the GG in the Kashan area emplaced at ca. 19–17 Ma (Burdigalian). All the samples of MMEs and granitoid host rocks in this study are metaluminous and calc‐alkaline with I‐type affinities. They are enriched in light rare earth elements (LREEs) and show slight negative Eu anomalies (Eu/Eu* = 0.36–0.95). These features in a combination with the relative depletion in Nb, Ta, Ti and P, indicate the granitoids and MMEs are closely associated with subduction‐related magmas at an active continental margin. The host rocks yield relatively homogeneous isotopic compositions of initial 87Sr/86Sr ratios ranging from 0.706036 to 0.707055, εNd(t) values varying from −2.25 to 0.8, and the Nd model ages (TDM) vary in a limited range of 0.70–0.96 Ga. The MMEs show similar initial 87Sr/86Sr ratios (0.706420–0.707366), εNd(t) values (−1.32 to −0.27), TDM (0.68–1.09 Ga) and Pb isotopic compositions with host granitoids, which imply they attained isotopic equilibration during magma mingling and mixing. In combination with the petrographic, chemical and isotopic results, we suggest that the origin of MMEs and their host rocks were related to the interaction between crust‐derived melts and mantle‐derived mafic magmas. The magma‐mixing event possibly occurred during the transition from subduction to collision in the UDMA along with the closure of the Neotethyan ocean. [ABSTRACT FROM AUTHOR]

Yanshanian magmatisms are intensive in the eastern Jiangnan orogen and can be divided into early (150–136 Ma) and late (136–120 Ma) stages. About these granitic rocks, the petrogenesis and associated tectonic setting are still hotly debated. The Taiping–Huangshan complex, a representative granitic rock in this region, is selected to perform geochemical studies. Three lithologic units have been identified in the Taiping–Huangshan complex: granodiorite, monzogranite, and alkali‐feldspar granite with zircon U–Pb dating results of 149–144 Ma, 148 Ma, and 135–131 Ma, respectively, belonging to the early stage for the granodiorite and monzogranite, and late stage for the alkali‐feldspar granite. The granodiorite and monzogranite have similar major and trace element characteristics with intermediate‐acidic SiO2 contents ranging from 65.9 to 69.7 wt.%, low Mg# values of 35.8–38.4, enriched LREE, Pb, Th, and U contents, and weak Eu anomalies (δEu = 0.71–0.79). The alkali‐feldspar granite is characterized by high SiO2 contents (73.3–76.6 wt.%), low Mg# (2.6–10.0), enriched Th, U, Ta, Pb, and Nd, depleted high‐field‐strength elements, and pronounced negative Eu anomalies (δEu = 0.01–0.19). The granodiorite and monzogranite have consistent εHf(t) (−5.38 to −9.41) and δ18O (7.18‰ to 11.00‰) values, while the alkali‐feldspar granite has elevated εHf(t) values (−0.96 to −6.48) and δ18O values (6.27‰ to 8.34‰). Integrated geochemical characteristics and batch partial melting modelling constrain that the early stage granitic rocks derived from ca. 8% batch melting of the Neoproterozoic juvenile crust, and the late‐stage granites derived from a similar crust source with a little contribution from mantle. From early to late stage, the tectonic setting translated from post‐orogenic to anorogenic and the later corresponded to a back‐arc extensional setting as increasing of the slab subducted angle of the Palaeo‐Pacific Plate. [ABSTRACT FROM AUTHOR]

The major Precambrian crustal growth in the North China Craton (NCC) has been thought to have occurred at ∼2.5 Ga. Here we present secondary ion mass spectroscopy (SIMS) and laser ablation-inductively coupled mass spectrometry (LA-ICP-MS) zircon U-Pb ages and Hf isotope compositions from dioritic and tonalite-trondhjemite-granodiorite (TTG) gneisses of the Neoarchean-Paleoproterozoic metamorphic terrane in the central NCC. Zircons from the trondhjemitic samples yield emplacement ages at 2,702±7 and 2,722±9 Ma. Those from the dioritic gneiss yield an age of 2,704±14 Ma. The TTG gneisses are characterized by a Na-rich and K-poor (Na/K ratiosp2.7, 2.6) nature; strongly fractionated rare earth element patterns ([La/Yb] p35, 20); high Sr (418‰, 318‰) and Sr/Y (78, 49); low Y N (5.4‰, 6.4‰) and YbN (3.0, 3.6); and low MgO (0.89%, 1.10%), Mg# (47, 42), Cr (39‰, 20‰), and Ni (11‰, 8‰), Nb/ Ta (16, 12), which suggests that magmas were derived from the partial melting of a flatly subducted oceanic slab. The dioritic gneiss shows higher MgO (3.17%), Mg# (50), Cr (44‰), and Ni (40‰) and lower Sr/Y (22) and (La/Yb)N (8) ratios, which suggests contamination with mantle peridotite. All zircon grains from these Neoarchean gneisses yield high positive εHf (t) values that range from ε3.5 to ε7.7 and Hf model ages between 2.70 and 2.85 Ga. We propose that the widespread ∼2.5-Ga plutonic event found elsewhere in the NCC may represent a major reworking (melting) event, whereas the ∼2.7-Ga magmatism likely represents the main crustal growth of the NCC, comparable to those of other cratons worldwide [ABSTRACT FROM AUTHOR]

Pan-African basement rocks and the Palaeozoic cover series of the Menderes Massif are exposed around Derbent (Alasehir) in the eastern part of the Ödemis-Kiraz submassif. Garnet-mica schists of the Pan-African basement are intruded by the protoliths of orthogneisses and Triassic leucocratic orthogneisses. This study focuses on the geochronology and geochemistry of orthogneisses related to the Pan-African evolution of the Menderes Massif in latest Proterozoic time. Geochemical data suggest that the orthogneisses were derived from S-type, peraluminous, syn- to post-collisional granitoids of calc-alkaline affinity. Zircon grains from the orthogneisses, which are euhedral with typical igneous morphologies, were dated by the Pb-Pb evaporation method. Single zircon ages of two samples yielded 207 Pb/ 206 Pb ages of 561.5±1.8 Ma and 570.5±2.2 Ma. These ages are interpreted as the time of protolith emplacement of the orthogneisses. This major magmatic episode of the Menderes Massif can be attributed the Pan-African Orogeny which was related to the closure of the ocean basins and amalgamation of East and West Gondwana. [ABSTRACT FROM AUTHOR]

The spatial position and interaction of drugs and their targets is the most important characteristics for understanding a drug's pharmacological effect, and it could help both in finding new and more precise treatment targets for diseases and in exploring the targeting effects of the new drugs. In this work, we develop a computational pipeline to confirm the spatial interaction relationship of the drugs and their targets and compare the drugs' efficacies based on the interaction centers. First, we produce a 100-sample set to reconstruct a stable docking model of the confirmed drug–target pairs. Second, we set 5.5 Å as the maximum distance threshold for the drug–amino acid residue atom interaction and construct 3-dimensional interaction surface models. Third, by calculating the spatial position of the 3-dimensional interaction surface center, we develop a comparison strategy for estimating the efficacy of different drug–target pairs. For the 1199 drug–target interactions of the 649 drugs and 355 targets, the drugs that have similar interaction center positions tend to have similar efficacies in disease treatment, especially in the analysis of the 37 targeted relationships between the 15 known anti-cancer drugs and 10 target molecules. Furthermore, the analysis of the unpaired anti-cancer drug and target molecules suggests that there is a potential application for discovering new drug actions using the sampling molecular docking and analyzing method. The comparison of the drug–target interaction center spatial position method better reflect the drug–target interaction situations and could support the discovery of new efficacies among the known anti-cancer drugs. [ABSTRACT FROM AUTHOR]

The Longwangzhuang pluton is a typical example of Paleoproterozoic A-type granite intrusions at the southern margin of the North China Craton. This pluton is composed of arfvedsonite granite and minor aegirine–augite granites. Samples from both granite types display similar zircon U-Pb ages with 207U-206Pb ages of 1612 ± 19 Ma [mean square weighted deviation (MSWD) = 0.66] and 1609 ± 24 Ma (MSWD = 0.5), respectively. The granites exhibit similar high silica (SiO2 = 71.1–73.4 wt.%), high alkaline (Na2O + K2O = 8.10–9.26 wt.%, K2O/Na2O > 1), and low Al2O3 (11.8–12.8 wt. %) contents and metaluminous to weakly peraluminous bulk chemistry. The chemical variations of the Longwangzhuang pluton suggest the effects of mineral fractionation. In addition, all samples show typical characteristics of A-type granites, such as high 10000Ga/Al ratios (4.10–7.28), high FeOtot/(FeOtot + MgO) ratios (0.88–0.99), and high Zr (484–1082 ppm), Ce (201–560 ppm), and Y (78–156 ppm) contents. The εNd(t) values and the (206Pb/204Pb)t, (207Pb/204Pb)t, and (208Pb/204Pb)t ratios of the arfvedsonite granite samples vary from −4.6 to –5.3, 15.021 to 17.349, 15.241 to 15.472, and 33.206 to 36.905, respectively, and those for the aegirine–augite granite sample amount at −0.2, 14.421, 15.175, and 33.706. The distinct and variable Nd and Pb isotope values indicate the presence of heterogeneous protoliths. Based on its geochemistry, its low initial Pb isotope ratios, and its enrichment in Nd isotopes, we infer that the Longwangzhuang A-type granite is the partial melting product of basement rocks such as the Taihua Group gneisses accompanied by some involvement of juvenile material from the mantle. Together with published data from other Paleoproterozoic A-type granite plutons exposed at the southern margin of the craton, our findings suggest that these granites had a similar origin. Furthermore, geochemically, they can be divided into two groups: A2-type, which formed earlier (~1.8–1.6 Ga), and A1-type, which formed later (~1.6–1.5 Ga). Combining this information with the variations in whole-rock Nd and zircon Hf isotopic composition at ca. 1.6 Ga, we propose that tectonic transformation from post-orogenic to anorogenic magmatism occurred at the southern margin of the North China Craton at that time. [ABSTRACT FROM AUTHOR]

In this contribution, we investigate the suitability of three igneous rock standards distributed by the Chinese Academy of Geological Sciences as international standard reference materials for Hf–Fe isotope determinations. We report Lu–Hf concentrations and Hf–Fe isotope compositions of Chinese National Standards (CNS) GSR-1 (granite), GSR-2 (andesite), and GSR-3 (basalt) in order to assess their homogeneity and give the first benchmark values. Experiments using spiked (isotope dilution) and non-spiked samples reveal an overall homogeneous Hf isotope composition for CNS GSR-2 and GSR-3 with 176 Hf/ 177 Hf = 0.282641 ± 6 (MSWD = 1.5, n = 10) and 0.282985 ± 04 (MSWD = 0.48, n = 10), respectively. In contrast to GSR-2 and GSR-3, two out of ten analyses of GSR-1 show elevated Hf concentrations in conjunction with less radiogenic Hf isotope compositions, considerably lower to −10.6 and −16.8 ɛ Hf units, respectively, compared to the average of the remainder analyses. We ascribe this heterogeneity to inherited zircon grains so often observed in granitic rocks. Iron isotope determinations on a subset of samples yields values of δ 57 Fe = +0.35 ± 0.02, +0.22 ± 0.05, +0.43 ± 0.02 (relative to IRMM-014, n = 3) for GSR-1, GSR-2, and GSR-3, respectively. Our results indicate that GSR-2 and GSR-3 appear suitable standards for Hf–Fe isotope analyses, but advise caution when using GSR-1 as a measure for quality control for Hf isotope compositions and concentrations. [ABSTRACT FROM AUTHOR]

The Karaburun Peninsula, which is considered part of the Anatolide-Tauride Block of Turkey, contains clastic and carbonate sequences deposited on the northern margin of Gondwana. The Palaeozoic clastic sequence, which is intruded by the Early Triassic granitoid and tectonically overlies a Mesozoic mélange sequence, can be divided into three subunits: a lower clastic subunit consisting of a sandstone-shale alternation, an upper clastic subunit consisting of black chert-bearing shales, sandstone and conglomerate, and a Permo-Carboniferous carbonate subunit. The lower Triassic Karaburun I-type granitoid has a high initial 87Sr/86Sr ratio (0.709021-0.709168), and low 143Nd/144Nd ratio (0.512004-0.512023) and εNd (-5.34 to -5.70) isotopic values. Geochronological data indicate a crystallization (intrusion) age of 247.1±2.0 Ma (Scythian). Geochemically, the acidic magmatism reflects a subduction-related continental-arc basin tectonic setting, which can be linked to the opening of the northern branch of Neo-Tethys as a continental back-arc rifting basin on the northern margin of Gondwana. This can be related to the closure through southward subduction of the Palaeotethys Ocean beneath Gondwana. [ABSTRACT FROM AUTHOR]

In our previous study on petrogenesis of quartz syenite and granite porphyry, the host rocks of the Late Mesozoic Shapinggou Mo deposit in the Qinling–Dabie orogenic belt, we found that the initial Sr isotopic composition of the host rocks is strongly affected by the degree of K-alteration. Here, we provide further isotopic evidence of the host rocks and their minerals to investigate the geochemical behaviour of trace elements and isotopes during the alteration and to explain the phenomenon of decoupling of Sr–Nd isotopic composition. The quartz syenite and granite porphyry are altered by K-alteration in varying degrees and have high K2O and Rb contents and low Na2O, CaO, Sr, and Ba contents. Rock samples of both quartz syenite and granite porphyry have variable Rb/Sr ratios and initial 87Sr/86Sr values (even < 0.70) but contain quite homogeneous εNd(t) values (−12.8 to −14.8). Minerals from the rocks of moderate to intense K-alteration have very low initial 87Sr/86Sr values (even < −17), while those from the weakly altered rocks have 87Sr/86Sr(t) values of 0.7044 to 0.7084. The same phenomenon of the decoupling in Sr–Nd isotopic composition can be observed from several Mo deposits within the eastern Qinling–Dabie orogenic belt. This fact suggests similar hydrothermal features and a comparable origin for both the magmatic rocks and hydrothermal fluids in this belt. A comparison between porphyry Mo and porphyry Cu deposits shows that elements and the Rb–Sr isotope system have different behaviours during the K-alteration, implying distinct material sources and igneous rocks for porphyry Mo and porphyry Cu deposits, respectively. [ABSTRACT FROM AUTHOR]

Background: Positron emission tomography (PET) and PET/computed tomography (PET/CT) imaging with 3,4-dihydroxy-6-[18F] fluoro-L-phenylalanine (18F-FDOPA) has been used in the evaluation of gliomas. We performed a meta-analysis to obtain the diagnostic and grading accuracy of 18F-FDOPA PET and PET/CT in patients with gliomas.Methods: PubMed, Embase, Cochrane Library and Web of Science were searched through 13 May 2019. We included studies reporting the diagnostic performance of 18F-FDOPA PET or PET/CT in glioma patients. Pooled sensitivity, specificity, and area under the summary receiver operating characteristic (SROC) curve were calculated from eligible studies on a per-lesion basis.Results: Eventually, 19 studies were included. Across 13 studies (370 patients) for glioma diagnosis, the pooled sensitivity and specificity of 18F-FDOPA PET and PET/CT were 0.90 (95%CI: 0.86-0.93) and 0.75 (95%CI: 0.65-0.83). Across 7 studies (219 patients) for glioma grading, 18F-FDOPA PET and PET/CT showed a pooled sensitivity of 0.88 (95%CI: 0.81-0.93) and a pooled specificity of 0.73 (95%CI: 0.64-0.81).Conclusions: 18F-FDOPA PET and PET/CT demonstrated good performance for diagnosing gliomas and differentiating high-grade gliomas (HGGs) from low-grade gliomas (LGGs). Further studies implementing standardized PET protocols and investigating the grading parameters are needed. [ABSTRACT FROM AUTHOR]