TiO2 Enrichment Research Articles

Sequential crystal overproduction triggering Mg-Cr-Ti-V-P-MREE- enrichment in a single-pulse tholeiitic mafic sill in the Central Iberian Zone, Spain

We study the causes of Mg-Cr-Ti-V-P-MREE enrichment in a 134 m thick mafic sill emplaced in a single magma pulse. Whole-rock chemistry indicates that TiO2 (up to 5.51 wt%) and P2O5 (up to 1.60 wt%) enrichment occurred in a closed system. Immiscibility processes during magmatic crystallization and interaction with late fluids seem to have played little or no role for the Ti-P distribution. Liquid lines of descent for anhydrous and hydrous conditions reveal that the melt did not follow a Fenner trend (anhydrous), which may lead to strong Ti or P enrichment, but a Bowen trend (hydrous), during crystallization at low fO2 (∆FMQ-2) and low water contents (0.5% H2O). The Mg-Cr-Ti-V-P-MREE-rich samples are cumulates and their composition is offset from the liquid line of descent due to postcumulus compaction and compositional convection. Theoretical formulation of compaction and compositional convection demonstrates that classical postcumulus scenarios of strong undercooling (sill <150 m thick) and high accumulation rates (ca. 1 m/y), using uniform cooling and anhydrous viscosity values, properly explain the observed Ti enrichment, but not the P and Cr enrichment. Latent heat released during overproduction of clinopyroxene, plagioclase, ilmenite, and apatite may result in non-uniform cooling with periods of near-isothermal conditions. Non-uniform cooling may locally reduce the accumulation rate, which temporarily enhances the efficiency of compaction and compositional convection and leads to the development of MgCr, TiV, or P-MREE-rich cumulates. The efficiency of postcumulus processes declines once the latent heat does not compensate heat loss to the country rock, leading to cumulates with high intergranular liquid fractions and without Cr, Ti, and P enrichment. High water contents in the upper level of the sill facilitate postcumulus processes and migration of residual liquids and fluids upwards, leading to the formation of abundant pegmatoid pockets and the development of a sandwich horizon that does not follow the liquid line of descent.

MASS SPECTROMETRY-BASED MITOCHONDRIAL PROTEOMICS IN HUMAN OVARIAN CANCERS.

The prominent characteristics of mitochondria are highly dynamic and regulatory, which have crucial roles in cell metabolism, biosynthetic, senescence, apoptosis, and signaling pathways. Mitochondrial dysfunction might lead to multiple serious diseases, including cancer. Therefore, identification of mitochondrial proteins in cancer could provide a global view of tumorigenesis and progression. Mass spectrometry-based quantitative mitochondrial proteomics fulfils this task by enabling systems-wide, accurate, and quantitative analysis of mitochondrial protein abundance, and mitochondrial protein posttranslational modifications (PTMs). Multiple quantitative proteomics techniques, including isotope-coded affinity tag, stable isotope labeling with amino acids in cell culture, isobaric tags for relative and absolute quantification, tandem mass tags, and label-free quantification, in combination with different PTM-peptide enrichment methods such as TiO2 enrichment of tryptic phosphopeptides and antibody enrichment of other PTM-peptides, increase flexibility for researchers to study mitochondrial proteomes. This article reviews isolation and purification of mitochondria, quantitative mitochondrial proteomics, quantitative mitochondrial phosphoproteomics, mitochondrial protein-involved signaling pathway networks, mitochondrial phosphoprotein-involved signaling pathway networks, integration of mitochondrial proteomic and phosphoproteomic data with whole tissue proteomic and transcriptomic data and clinical information in ovarian cancers (OC) to in-depth understand its molecular mechanisms, and discover effective mitochondrial biomarkers and therapeutic targets for predictive, preventive, and personalized treatment of OC. This proof-of-principle model about OC mitochondrial proteomics is easily implementable to other cancer types. © 2020 John Wiley & Sons Ltd. Mass Spec Rev.

An abnormal correlation between electron work function and corrosion resistance in Ti-Zr-Be-(Ni/Fe) metallic glasses

In this work, we correlate corrosion behaviour of metallic glasses (MGs) to electron characteristic based on magnitude and local distribution of electron work function (EWF). An abnormal phenomenon has been addressed that a low EWF leads to superior corrosion resistance in 3.5 wt.% NaCl solution for Ti-Zr-Be-(Ni-Fe) MGs. Because a low EWF, corresponding to high electron activity, facilitates interfacial passivation reactions to form highly protective passive film, which is accompanied by the enrichment of TiO2 and ZrO2. Besides, heterogeneous EWF-distribution that is related to electrochemical heterogeneity, indicates the formation of preferential sites for pitting nucleation, therefore deteriorating corrosion resistance.

Mineral Magnetic and Geochemical Mapping of the Wular Lake Sediments, Kashmir Valley, NW Himalaya

This study presents major element geochemistry, mineral magnetism and textural analysis of lake-bottom sediments collected from the Wular Lake located in the Kashmir Valley (northwest Himalaya). Connected to the Jhelum River, Wular Lake basin occupies ~ 75% watershed area of the valley, covering ~ 10,196 km2, and makes it the major depo-centre for Kashmir Valley. The sediments represent dominant silt fraction with TiO2, MgO, Fe2O3 and MnO enrichment; and depletion of Na2O and P2O5 with reference to upper continental crust. The average CIA (64.17%) reflects moderate chemical weathering of the catchment source rocks. The mineral magnetic mapping identified distinct domains of restricted/reducing and well-ventilated/oxic conditions, illustrating spatial environmental variability within the lake-bottom environments. The geochemical and mineral magnetic mapping therefore provides a baseline reference for emerging climate and anthropogenic changes being experienced in the Kashmir Valley.

Comparative phosphorylation map of Dishevelled 3 links phospho-signatures to biological outputs

BackgroundDishevelled (DVL) is an essential component of the Wnt signaling cascades. Function of DVL is controlled by phosphorylation but the molecular details are missing. DVL3 contains 131 serines and threonines whose phosphorylation generates complex barcodes underlying diverse DVL3 functions. In order to dissect the role of DVL phosphorylation we analyzed the phosphorylation of human DVL3 induced by previously reported (CK1ε, NEK2, PLK1, CK2α, RIPK4, PKCδ) and newly identified (TTBK2, Aurora A) DVL kinases.MethodsShotgun proteomics including TiO2 enrichment of phosphorylated peptides followed by liquid chromatography tandem mass spectrometry on immunoprecipitates from HEK293T cells was used to identify and quantify phosphorylation of DVL3 protein induced by 8 kinases. Functional characterization was performed by in-cell analysis of phospho-mimicking/non-phosphorylatable DVL3 mutants and supported by FRET assays and NMR spectroscopy.ResultsWe used quantitative mass spectrometry and calculated site occupancies and quantified phosphorylation of > 80 residues. Functional validation demonstrated the importance of CK1ε-induced phosphorylation of S268 and S311 for Wnt-3a-induced β-catenin activation. S630–643 cluster phosphorylation by CK1, NEK2 or TTBK2 is essential for even subcellular distribution of DVL3 when induced by CK1 and TTBK2 but not by NEK2. Further investigation showed that NEK2 utilizes a different mechanism to promote even localization of DVL3. NEK2 triggered phosphorylation of PDZ domain at S263 and S280 prevents binding of DVL C-terminus to PDZ and promotes an open conformation of DVL3 that is more prone to even subcellular localization.ConclusionsWe identify unique phosphorylation barcodes associated with DVL function. Our data provide an example of functional synergy between phosphorylation in structured domains and unstructured IDRs that together dictate the biological outcome.6BqYee6BDHWtLZWNZ_gBTSVideo Abtract.Graphical abstract

SC335 - TiO2 enrichment and highly sensitive mass spectrometric analysis for high-throughput detection of low abundance sialylated glycoproteins in blood serum of prostate cancer patients

SC335 - TiO2 enrichment and highly sensitive mass spectrometric analysis for high-throughput detection of low abundance sialylated glycoproteins in blood serum of prostate cancer patients

Studies on microstructure and mechanical properties of modified 9Cr–1Mo (P91) steel in submerged arc welding with TiO2-enriched fluxes

In the present work is studied the influence of titanium dioxide on the microstructure and mechanical properties of submerged arc weld P91 steel weldment. To manipulate the chemical composition of the weldment, the titanium dioxide (TiO2) powder was added with fresh welding flux in various proportions (2.5–12.5%). The results of optical emission spectroscopy test showed that Ti wt% is systematically increased from 0.00 to 0.021, whereas, other alloying elements were fairly uniform. The micrographs of the scanning electron microscope reveal the presence of finely dispersed precipitates in the weld metals, and the percentage of precipitation increases with respect to the enrichment of titanium dioxide. The hardness profile of weld metal increases significantly with respect to the TiO2 addition. Formation of TiC and TiN could be the possible reason for the enhancement of hardness, which has a positive impact on the creep property of steel weldment. Enrichment of TiO2 reveals the appreciable improvement in the tensile strength properties. However, the highest percentage of TiO2 addition provides the adverse effect on the yield strength and ultimate tensile strength values. The presence of surplus quantity of oxide content into the weld metal could be the possible reason behind this. Toughness value of the weld samples showed the negative trend with the addition of TiO2 which can be increased by increasing the post-weld heating time.

The Protein Phosphorylation Landscape of Mouse Spermatids during Spermiogenesis.

The characteristic tadpole shape of sperm is formed from round spermatids via spermiogenesis, a process which results in dramatic morphological changes in the final stage of spermatogenesis in the testis. Protein phosphorylation, as one of the most important post-translational modifications, can regulate spermiogenesis; however, the phosphorylation events taking place during this process have not been systematically analyzed. In order to better understand the role of phosphorylation in spermiogenesis, large-scale phosphoproteome profiling is performed using IMAC and TiO2 enrichment. In total, 13835 phosphorylation sites, in 4196 phosphoproteins, are identified in purified mouse spermatids undergoing spermiogenesis in two biological replicates. Overall, 735 testis-specific proteins are identified to be phosphorylated, and are expressed at high levels during spermiogenesis. Gene ontology analysis shows enrichment of the identified phosphoproteins in terms of histone modification, cilium organization, centrosome and the adherens junction. Further characterization of the kinase-substrate phosphorylation network demonstrates enrichment of phosphorylation substrates related to the regulation of spermiogenesis. This global protein phosphorylation landscape of spermiogenesis shows wide phosphoregulation across a diverse range of processes during spermiogenesis and can help to further characterize the process of sperm generation. All MS data are available via ProteomeXchange with the identifier PXD011890.

Subduction and rollback of the paleo-Pacific plate during the Early Cretaceous: Insights from the Jiangmiao gabbroic intrusion in the Lower Yangtze River Belt, central-eastern China

The dynamics of Mesozoic tectonism recorded by the Lower Yangtze River Belt (LYRB), located in central-eastern China, are controversial. Between 148 and 123 Ma, three major and continuous stages of magmatism occurred in the LYRB: 1) high-K calc-alkaline intrusions, 2) andesitic shoshonitic volcanism, and 3) A-type granitic intrusions. The Jiangmiao gabbroic intrusion, which is located at the eastern end of the LYRB, is composed of gabbro and diorite and was emplaced at ~124 Ma (Dong et al., 2017; Sun et al., 2017a), simultaneous with the A-type granites of the third stage of Mesozoic magmatism in the LYRB. Petrography and mineral chemistry indicate that the Jiangmiao intrusion was formed by the intense crystal fractionation of an oxidized (ΔNNO ca. +1.0) and hydrous (3.5–4.5 wt% H2O) basaltic magma that produced the evolved dioritic magma and gabbroic cumulate. The accumulation of magnetite, olivine, clinopyroxene, and plagioclase resulted in abnormally high Fe2O3 (12.44–16.30 wt%) and low SiO2 (40.75–45.88 wt%) contents in the gabbro, as well as the enrichment of TiO2, Sr, Cr, Ni, Co, and V in the gabbro compared with the diorite. Intense crystal fractionation coupled with the fluid transport led to the enrichment of highly fluid-mobile elements (Rb, Th, U, and Pb) in the evolved diorite but depletion of these elements in the gabbro. The mineral chemistry of clinopyroxene and whole-rock Sr−Nd−Pb isotopic compositions indicate that the primitive basaltic magma originated from the partial melting of an enriched lithospheric mantle source in a subduction environment, but more asthenosphere mantle components were incorporated into the magma source compared with the earlier Mesozoic magmatic rocks in the LYRB. The coevality of the Jiangmiao gabbroic intrusion and the A-type granites supports the tectonic model of Mesozoic rollback of the westward-subducting paleo-Pacific plate. The Jiangmiao gabbroic intrusion likely represents the edge of the back-rolling slab at ~124 Ma, whereas the simultaneous A-type granites in the middle of the LYRB were formed as a result of intraplate extension generated by rollback.

Glucose-dependent phosphorylation signaling pathways and crosstalk to mitochondrial respiration in insulin secreting cells

BackgroundGlucose is the main secretagogue of pancreatic beta-cells. Uptake and metabolism of the nutrient stimulates the beta-cell to release the blood glucose lowering hormone insulin. This metabolic activation is associated with a pronounced increase in mitochondrial respiration. Glucose stimulation also initiates a number of signal transduction pathways for the coordinated regulation of multiple biological processes required for insulin secretion.MethodsShotgun proteomics including TiO2 enrichment of phosphorylated peptides followed by liquid chromatography tandem mass spectrometry on lysates from glucose-stimulated INS-1E cells was used to identify glucose regulated phosphorylated proteins and signal transduction pathways. Kinase substrate enrichment analysis (KSEA) was applied to identify key regulated kinases and phosphatases. Glucose-induced oxygen consumption was measured using a XF96 Seahorse instrument to reveal cross talk between glucose-regulated kinases and mitochondrial activation.ResultsOur kinetic analysis of substrate phosphorylation reveal the molecular mechanism leading to rapid activation of insulin biogenesis, vesicle trafficking, insulin granule exocytosis and cytoskeleton remodeling. Kinase-substrate enrichment identified upstream kinases and phosphatases and time-dependent activity changes during glucose stimulation. Activity trajectories of well-known glucose-regulated kinases and phosphatases are described. In addition, we predict activity changes in a number of kinases including NUAK1, not or only poorly studied in the context of the pancreatic beta-cell. Furthermore, we pharmacologically tested whether signaling pathways predicted by kinase-substrate enrichment analysis affected glucose-dependent acceleration of mitochondrial respiration. We find that phosphoinositide 3-kinase, Ca2+/calmodulin dependent protein kinase and protein kinase C contribute to short-term regulation of energy metabolism.ConclusionsOur results provide a global view into the regulation of kinases and phosphatases in insulin secreting cells and suggest cross talk between glucose-induced signal transduction and mitochondrial activation.

Phosphorylated proteomics analysis of human coronary artery endothelial cells stimulated by Kawasaki disease patients serum

BackgroundKawasaki disease (KD) is an acute febrile childhood systemic vasculitis that disturbs coronary arteries. The pathogenesis remains unknown. The study of phosphorylated proteins helps to elucidate the relevant pathophysiological mechanisms of cardiovascular disease. However, few researches explored phosphorylated proteins in KD patients.MethodsWe compared phosphoprotein profiles of HCAECs stimulated by the serum of KD patients and normal children using iTRAQ technology, TiO2 enrichment phosphorylated peptide and MS analysis. Then we conducted the functional analysis by ClueGO and the biological interaction networking analysis by ReactomeFIViz. Western blotting was performed to identify the hub proteins.ResultsOur results revealed that phosphorylation of 148 proteins showed different intensities between the two HCAECs groups, which are enriched in MAPK, VEGFR, EGFR, Angiopoietin receptor, mTOR, FAK signaling pathway and so on. Through the Network Analyzer analysis, the hub proteins are CDKN1A, MAPK1 and POLR2A, which were experimentally validated.ConclusionIn summary, we provided evidence addressing the valuable phosphorylation signaling that could be useful resource to understand the molecular mechanism and the potential targets for novel therapy of KD.

The Investigation on Enrichment of TiO2 from Ti-Bearing Slag

Titanium-bearing slag in this study was produced by subjecting titanium-bearing sea sand iron mineral to direct reduction smelting process. The enrichment and growth of titanium-rich phase in the titanium slag were investigated. The phases in slag were characterized by X-ray diffraction, optical microscopy, scanning electron microscopy and energy dispersive spectroscopy. The results showed that Ti-rich phase had a pseudobrookite structure, and it was close to diffractogram of anosovite phase (M3O5 (M = Mg, Al, Ti)), in which the theoretical content of TiO2 is 73.2%. Line-scanning analysis was used to clarify the elements distribution trend in titanium slag. The results showed that Ti element was enriched in the anosovite phase, and Si and Ca assembled in the matrix phase. Mg and Fe elements were distributed in larger proportion in the anosovite phase, while the Al element was more enriched in the matrix phase. The experimental results showed that low cooling rate was in favor of titanium precipitate in anosovite phase. Moreover, the growth of anosovite crystal was characterized by kinetic model. These results provided further insights into the separation of anosovite from gangue by mineral processing.

High-throughput detection of low abundance sialylated glycoproteins in human serum by TiO2 enrichment and targeted LC-MS/MS analysis: application to a prostate cancer sample set.

Glycopeptide enrichment can be a strategy to allow the detection of peptides belonging to low abundance proteins in complex matrixes such as blood serum or plasma. Though several glycopeptide enrichment protocols have shown excellent sensitivities in this respect, few reports have demonstrated the applicability of these methods to relatively large sample cohorts. In this work, a fast protocol based on TiO2 enrichment and highly sensitive mass spectrometric analysis by Selected Reaction Monitoring (SRM) has been applied to a cohort of serum samples from prostate cancer and benign prostatic hyperplasia patients in order to detect low abundance proteins in a single LC-MS/MS analysis in nanoscale format, without immunodepletion or peptide fractionation. A peptide library of over 700 formerly N-glycosylated peptides was created by data dependent analysis. Then, 16 medium to low abundance proteins were selected for detection by single injection LC-MS/MS based on selected-reaction monitoring. Results demonstrated the consistent detection of the low-level proteins under investigation. Following label-free quantification, four proteins (Adipocyte plasma membrane-associated protein, Periostin, Cathepsin D and Lysosome-associated membrane glycoprotein 2) were found significantly increased in prostate cancer sera compared to the control group. Graphical abstract ᅟ.

Geochemistry and grain size distribution of surface sediments of a large semi-enclosed lagoon connected to the western Bay of Bengal

Batticaloa is a large (135.5 km2), semi-enclosed, micro-tidal lagoon that formed by barrier deposits in eastern Sri Lanka and has a unique geographic position due to its tropical monsoonal climate and absence of tectonics. The recent soft bottom sediments of Batticaloa lagoon were studied on the basis of geochemistry and grain size distribution in order to interpret their characteristics and provenance. Poor to moderately sorted medium sands are the dominant sedimentary deposits for the lagoon; therefore, a medium energy condition is suggested for sediment deposition. The average silt and clay fraction of the lagoon sediments is less than 3%, indicating medium or high energy flows. Coarser deposits are restricted to channel and lagoon mouths. The scatter plots of Nb, Zr, Cr and Sc vs. Th and Cr/V vs. Y/Ni show a felsic provenance for the sediments. The normalized diagrams of major element oxides and trace elements for the regional rocks (Vijayan Complex of Sri Lanka) indicate high country rock influence for the sedimentation for the semi-enclosed setting. The enrichment and distribution of Zr, Th, Nb, Cr and TiO2 suggest the possibility of mineral sands that are fractionated with hydrodynamic setting of the lagoon.

Quantitative Proteomics and Phosphoproteomics Analysis Revealed Different Regulatory Mechanisms of Halothane and Rendement Napole Genes in Porcine Muscle Metabolism.

Pigs with the Halothane (HAL) or Rendement Napole (RN) gene mutations demonstrate abnormal muscle energy metabolism patterns and produce meat with poor quality, classified as pale, soft, and exudative (PSE) meat, but it is not well understood how HAL and RN mutations regulate glucose and energy metabolism in porcine muscle. To investigate the potential signaling pathways and phosphorylation events related to these mutations, muscle samples were collected from four genotypes of pigs, wild type, RN, HAL, and RN-HAL double mutations, and subjected to quantitative proteomic and phosphoproteomic analysis using the TiO2 enrichment strategy. The study led to the identification of 932 proteins from the nonmodified peptide fractions and 1885 phosphoproteins with 9619 phosphorylation sites from the enriched fractions. Among them, 128 proteins at total protein level and 323 phosphosites from 91 phosphoproteins were significantly regulated in mutant genotypes. The quantitative analysis revealed that the RN mutation mainly affected the protein expression abundance in muscle. Specifically, high expression was observed for proteins related to mitochondrial respiratory chain and energy metabolism, thereby enhancing the muscle oxidative capacity. The high content of UDP-glucose pyrophosphorylase 2 (UGP2) in RN mutant animals may contribute to high glycogen storage. However, the HAL mutation mainly contributes to the up-regulation of phosphorylation in proteins related to calcium signaling, muscle contraction, glycogen, glucose, and energy metabolism, and cellular stress. The increased phosphorylation of Ca2+/calmodulin-dependent protein kinase II (CAMK2) in HAL mutation may act as a key regulator in these processes of muscle. Our findings indicate the different regulatory mechanisms of RN and HAL mutations in relation to porcine muscle energy metabolism and meat quality.

Targeted Quantification of Phosphorylation Dynamics in the Context of EGFR-MAPK Pathway.

Large-scale phosphoproteomics with coverage of over 10,000 sites of phosphorylation have now been routinely achieved with advanced mass spectrometry (MS)-based workflows. However, accurate targeted MS-based quantification of phosphorylation dynamics, an important direction for gaining quantitative understanding of signaling pathways or networks, has been much less investigated. Herein, we report an assessment of the targeted workflow in the context of signal transduction pathways, using the epidermal growth factor receptor (EGFR)-mitogen-activated protein kinase (MAPK) pathway as our model. A total of 43 phosphopeptides from the EGFR-MAPK pathway were selected for the study. The recovery and sensitivity of two commonly used enrichment methods, immobilized metal affinity chromatography (IMAC) and titanium oxide (TiO2), combined with selected reaction monitoring (SRM)-MS were evaluated. The recovery of phosphopeptides by IMAC and TiO2 enrichment was quantified to be 38 ± 5% and 58 ± 20%, respectively, based on internal standards. Moreover, both enrichment methods provided comparable sensitivity from 1 to 100 μg starting peptides. Robust quantification was consistently achieved for most targeted phosphopeptides when starting with 25-100 μg peptides. However, the numbers of quantified targets significantly dropped when peptide samples were in the 1-25 μg range. Finally, IMAC-SRM was applied to quantify signaling dynamics of EGFR-MAPK pathway in Hs578T cells following 10 ng/mL EGF treatment. The kinetics of phosphorylation clearly revealed early and late phases of phosphorylation, even for very low abundance proteins. These results demonstrate the feasibility of robust targeted quantification of phosphorylation dynamics for specific pathways, even starting with relatively small amounts of protein.

Tectonic significance of the Late Carboniferous Zhunmubutai ophiolitic mélange from Xi‐Ujimqin, Inner Mongolia

The Zhunmubutai ophiolitic mélange is a newly discovered ophiolite suite located between the Solonker‐Linxi ophiolite belt and the Erenhot‐Hegenshan‐Xi‐Ujimqin ophiolite belt, the central part of Xilinhot Microcontinent (XLMC). It was composed of plagiogranite, pyroxene peridotite, pillow basaltic andesite, and associated mafic rocks and surrounded by a quartz diorite pluton and mélange zone containing sandstones and slates of Early Permian Shoushangou Formation. In this study, zircon grains from a quartz diorite and a plagiogranite yield 206Pb/238U ages of 313 ± 1 Ma (MSWD = 1.60, n = 20) and 328 ± 1 Ma (MSWD = 0.9, n = 93), respectively. Sixty‐four zircons from the slate yielded ages ranging from 307 to 2,313 Ma, and with a peak at 340 Ma. These data indicate the Zhunmubutai ophiolitic mélange formed 300 to 340 Ma. The Zhunmubutai plagiogranites that have low contents of K2O (0.07–0.33 wt.%), K2O/Na2O (0.02–0.09), and Rb/Sr (0.01–0.05) show an oceanic plagiogranites affinity. They are also characterized by low contents of TiO2, Nd, Ta, and significant LREE enrichment. Furthermore, the εHf (328 Ma) values range from 14.23 to 18.87. These features suggest that the plagiogranite was originated by the anatexis of amphibolites and with crustal contamination. Combined with previous studies, suggest that the Zhunmubutai ophiolitic mélange may have formed in an extensional environment during the early stages of opening of an ocean basin.

The newly-discovered Late Cretaceous igneous rocks in the Nuocang district: Products of ancient crust melting trigged by Neo–Tethyan slab rollback in the western Gangdese

The newly discovered polymetallic Nuocang Pb-Zn skarn deposit is located in the southern Lhasa subterrane, western Gangdese, Tibet. The orebodies occur primarily at the contact zone between the Angjie Formation and the Linzizong volcanic rocks of Dianzhong Formation (LDF) that are dominated by basaltic andesitic tuff and rhyolite. Zircon U–Pb dating for two granite porphyries yield ages of 72.4 ± 0.2 Ma and 73.4 ± 0.9 Ma, which are different from the ages (~69–60 Ma) of the LDF in the eastern Gangdese. The basaltic andesite tuff at Nuocang exhibits enrichment of MgO, TiO2, LILE, and LREE, with a relative depletion of SiO2, K2O, HFSE, and HREE, low Sr/Y ratios (32.9–38.0), and weak negative Eu anomalies (mean 0.86). They have 87Sr/86Sr(i) from 0.70695 to 0.70807 and εNd(t) values between −4.3 and −5.9. These features are similar to the Linzizong volcanic rocks of Dianzhong Formation in the Linzhou basin, indicating that they were associated with partial melting of mantle wedge mixing with 25–35% ancient Lhasa terrane basement. The rhyolite and granite porphyry show high SiO2 and K2O, and low Sr/Y ratio (1.2–9.9), enrichment of LILE and LREE and strong depletion of the HFSEs. They have pronounced negative Eu anomalies (mean 0.46), and εHf (t) values of the granite porphyry zircons range from −22.0 to −6.0. All these features suggest that they are the product of anatexis of ancient crustal materials heated by mantle-derived magma, the latter derived from Neo-Tethyan slab dehydration mechanisms. Combined with the previous geochronological and geochemical data, we proposed that the Nuocang district of western Gangdese in the southern Lhasa subterrane contains an ancient block, and the igneous rocks here were triggered by the Neo-Tethyan slab rollback starting at ~82 Ma. The western Gangdese contains more ancient continental crustal materials and Late Cretaceous–Eocene Linzizong volcanic rocks and coeval intrusions than in the eastern Gangdese. Thus the western Gangdese block displays greater potential for deposits associated with Late Cretaceous-Eocene magmatism including porphyry Mo, polymetallic skarn (W-Sn-Mo-Pb-Zn-Ag), base and precious metal epithermal (Pb-Zn-Ag-Au), cryptoexplosive breccia (Pb-Zn-Ag), and hydrothermal vein Pb-Zn-Ag deposits.

Integration of remote sensing, geochemical and field data in the Qena-Safaga shear zone: Implications for structural evolution of the Eastern Desert, Egypt

The Qena-Safaga shear zone (QSSZ) represents a significant structural characteristic in the Eastern Desert of Egypt. Remote Sensing, field and geochemical data were utilized in the present study. The results revealed that the QSSZ dominated by metamorphic complex (MC) that intruded by syn-tectonic granitoids. The low angle thrust fault brings calc-alkaline metavolcanics to overlie MC and its association. Subsequently, the area is dissected by strike-slip faults and the small elongated basins of Hammamat sediments of Precambrian were accumulated. The MC intruded by late-to post-tectonic granites (LPG) and Dokhan Volcanics which comprise felsic varieties forming distinctive columnar joints. Remote sensing analysis and field data revealed that major sub-vertical conspicuous strike-slip faults (SSF) including sinistral NW-SE and dextral ca. E-W shaped the study area. Various shear zones that accompanying the SSF are running NW-SE, NE-SW, E-W, N-S and ENE-WSW. The obtained shear sense presented a multiphase of deformation on each trend. i.e., the predominant NW-SE strike-slip fault trend started with sinistral displacement and is reactivated during later events to be right (dextral) strike slip cutting with dextral displacement the E-W trending faults; while NE-SW movements are cut by both the N-S and NNW - SSE trends. Remote sensing data revealed that the NW-SE direction that dominated the area is associated with hydrothermal alteration processes. This allowed modifying the major and trace elements of the highly deformed rocks that showed depletion in SiO2 and enrichments in Fe2O3, MnO, Al2O3, TiO2, Na2O, K2O, Cu, Zn and Pb contents. The geochemical signatures of major and trace elements revealed two types of granites including I-type calc-alkaline granites (late-to post-tectonic) that formed during an extensional regime. However, syn-tectonic granitoids are related to subduction-related environment.

Comparative muscle proteomics/phosphoproteomics analysis provides new insight for the biosafety evaluation of fat-1 transgenic cattle.

The biosafety of fat-1 transgenic cattle has been a focus of our studies since the first fat-1 transgenic cow was born. In this study, we used tandem mass tag labeling, TiO2 enrichment, and nanoscale liquid chromatography coupled with tandem mass spectrometry (nanol LC-MS/MS) to compare proteomic and phosphoproteomic profiling analyses of muscle between fat-1 transgenic cows and wild-type cows. A total of 1555 proteins and 900 phosphorylation sites in 159 phosphoproteins were identified in the profiling assessments, but only four differentially expressed proteins and nine differentially expressed phosphopeptides were detected in fat-1 transgenic cows relative to wild-type cows. Bioinformatics analyses showed that all of the identified proteins and phosphoproteins were mainly related to the metabolic processes of three major nutrients: carbohydrates, lipids, and proteins. All of these differentially expressed proteins might take part in DNA recombination, repair, and regulation of the immune system. In conclusion, most of the identified proteins and phosphoproteins exhibited few changes. Our results provide new insights into the biosafety of fat-1 transgenic cattle.