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Sevoflurane induces developmental neurotoxicity in mice; however, the underlying mechanisms remain unclear. Triggering receptor expressed on myeloid cells 2 (TREM2) is essential for microglia-mediated synaptic refinement during the early stages of brain development. We explored the effects of TREM2 on dendritic spine pruning during sevoflurane-induced developmental neurotoxicity in mice. Mice were anaesthetized with sevoflurane on postnatal days 6, 8, and 10. Behavioral performance was assessed using the open field test and Morris water maze test. Genetic knockdown of TREM2 and overexpression of TREM2 by stereotaxic injection were used for mechanistic experiments. Western blotting, immunofluorescence, electron microscopy, three-dimensional reconstruction, Golgi staining, and whole-cell patch-clamp recordings were performed. Sevoflurane exposures upregulated the protein expression of TREM2, increased microglia-mediated pruning of dendritic spines, and reduced synaptic multiplicity and excitability of CA1 neurons. TREM2 genetic knockdown significantly decreased dendritic spine pruning, and partially aggravated neuronal morphological abnormalities and cognitive impairments in sevoflurane-treated mice. In contrast, TREM2 overexpression enhanced microglia-mediated pruning of dendritic spines and rescued neuronal morphological abnormalities and cognitive dysfunction. TREM2 exerts a protective role against neurocognitive impairments in mice after neonatal exposures to sevoflurane by enhancing microglia-mediated pruning of dendritic spines in CA1 neurons. This provides a potential therapeutic target in the prevention of sevoflurane-induced developmental neurotoxicity. [ABSTRACT FROM AUTHOR]

An editorial focuses on the discovery and significance of layered chromite mineralization within mafic-ultramafic rocks in the Gayahe area of the East Kunlun Orogenic Belt, Northwestern China. It highlights the identification of chromitite layers with high ore grades, marking a significant find in an area previously lacking economically valuable chromite deposits.

An editorial focuses on the newly discovered Jinshui tin deposit located in the middle section of the East Kunlun Orogenic Belt in northwestern China. It highlights the mineralization age of the deposit, determined through U-Pb dating of zircon and cassiterite, and discusses its implications for exploration in this region. It reports that the Jinshui deposit represents a significant addition to the known tin deposits in the area, with the ages of mineralization and magmatic activity.

The COVID-19 pandemic has caused fluctuations in electricity demand, altering people's lifestyles and electricity usage patterns, thereby affecting the accuracy of demand predictions. However, existing studies on electricity forecasting have not adequately considered the incorporation of COVID-19-related features and the analysis of electricity usage characteristics across different regions of the UK. Therefore, this paper, based on data of the UK's national electricity demand, conducts an analysis around the scenario of a large-scale health emergency in society. We explore the changing patterns and regional characteristics of electricity consumption during the COVID-19 pandemic, comparing the forecast results before and during the pandemic to illustrate its impact on the UK's electricity demand. By introducing COVID-19-related features into the models, we compare the forecast results before and after their inclusion. The results indicate that the COVID-19 pandemic has had a certain impact on the electricity prediction in the UK, leading to a 22.8% decrease in prediction accuracy. However, the models' correlation improved with the inclusion of COVID-19-related features, resulting in a 13.2% enhancement in prediction accuracy compared to the previous models. Additionally, the study summarizes other factors influencing electricity demand, such as power imports/exports and clean energy usage, as considerations for electricity distribution planning. This contributes to improving the accuracy of predicting the UK's electricity demand during COVID-19 pandemic, enabling the government to adjust power dispatching plans reasonably based on relevant factors, achieving rational distribution and efficient scheduling of power resources. [ABSTRACT FROM AUTHOR]

A large number of concrete-filled CFRP steel tube structures are widely used in practical engineering at current. Considering that as a column structure, compressive-shear loading is a more important bearing capacity method. 12 specimens are designed to study the comperssive-shear performance of concrete filled CFRP steel tube. The shear loading- displacement (V-Δ) curves and the collaborative work performance between the steel tube and CFRP are tested. Based on the tests, a numerical simulation method is firstly proposed to estimate the compressive-shear performance of concrete-filled CFRP steel tube stub column, and then validated against the representative tests results.Parametric study is conducted to explore the influence of principle factors on compresive-shear behaviour by verified numerical models. The experimental results show that the steel tube and CFRP can work together. As the axial compression ratio increases, the shear displacement of the specimen is constrained, resulting in increase of bearing capacity. Additionally, the increase of steel ratio, CFRP layers and materials strength for specimens enhance not only the bearing capacity but also the initial stiffness. The simulation results of the established finite element model are in good agreement with the experimental results. Finally, Based on experimental and finite element results, the bearing capacity correlation equation for concrete-filled square CFRP steel tublar stub columns when subjected to compressive-shear loading is presented. [ABSTRACT FROM AUTHOR]

The world-class Huize deposit hosts significant germanium (Ge) resources in the Sichuan–Yunan–Guizhou (SYG) Mississippi Valley-type (MVT) Pb–Zn province of China. The distribution and enrichment mechanism of Ge is still poorly understood. In the main ore-forming stage of Huize, we identified six sphalerite colors from C1 (black) to C6 (white) in transmitted light. Two color sequences are confirmed, including C1 → C2 → C3 → C6 and C1 → C2 → C4 → C5 → C6. We used multiple analytical methods to reveal the Ge distribution and incorporation mechanism into sphalerite and the possible enrichment factors. Our results show that Ge occurs as argutite (GeO2), and in the sphalerite crystal lattice, C1 and C3 sphalerite has up to 593 ppm Ge. Two substitution mechanisms, i.e., Ge4+ + □(vacancy) → 2Zn2+ (e.g., C1 and C2) and Ge4+ + 2Cu+ → 3Zn2+ (e.g., C2, C3, C4, and C5), are inferred from the Huize sphalerite. They show different spatial structures of sphalerite and a weak shift of the white line observed by high-resolution X-ray absorption near-edge structure (XANES) spectroscopy. The trace-element composition of sphalerite suggests that reduced sulfur content of the ore-forming fluid contributes to Ge enrichment, followed by high temperature (> 300 °C). [ABSTRACT FROM AUTHOR]

Intrahepatic cholestasis of pregnancy (ICP) can lead to many adverse pregnancy outcomes, and the influencing factors remain unclear at present. This study retrospectively analyzed clinical data from 1815 pregnant women with ICP and evaluated the relationship between ICP subtypes, gestational age at onset, and pregnancy outcomes. The results of this study show that during pregnancy, the levels of biochemical indicators (TBA, DBIL and ALT) in the serum of pregnant women initially diagnosed with subtypes of ICP were noted to constantly change, and the subtype of ICP and its severity also changed. The incidence of adverse pregnancy outcomes [meconium-stained amniotic fluid (MSAF), NICU transfer, Apgar score ≤ 7 at 1 min, and preterm birth] in patients with ICP1 (icteric type) was significantly higher than for patients with ICP2, ICP3 or ICP4. The preterm birth rate of early-onset ICP was higher than that of late-onset ICP in ICP1 and ICP3 subtypes. In conclusion, the outcome of pregnancy in women with ICP is closely related to the serum TBA level and ICP subtype, which should be recognized in the clinic. [ABSTRACT FROM AUTHOR]

High-rotational-speed friction stir welding (HRFSW) has gained significant attention in the field of friction stir welding due to its numerous advantages, including minimal workpiece deformation, low load requirements, rapid weld cooling, and improved mechanical properties with refined grains at the joint. This study conducted a HRFSW experiment on 1 mm thick 6061-T6 aluminum alloy sheets with stirring speeds ranging from 8,000 to 12,000 rpm and a constant transverse speed of 300 mm/min. During the HRFSW process, real-time temperature measurements were performed at the welded joint. A numerical analysis of the temperature and strain fields was conducted utilizing the coupled Eulerian–Lagrangian (CEL) method. A novel mathematical model of microhardness was introduced and incorporated into the CEL algorithm via a VUSDFLD subroutine to predict the mechanical properties of the welded joints. The results demonstrated that the peak temperature at the joint area during HRFSW increases with increasing penetration depth or rotational speed of the stirring tool. The observed asymmetry in the temperature field was attributed to variations in the strain distribution. Furthermore, peak strains consistently appeared in regions characterized by higher material flow rates. Physical experiments validated the established model, demonstrating its ability to accurately capture the variations in microhardness according to different microstructural features within the welded joint. This study provides a substantial understanding of the thermomechanical behavior of materials during the HRFSW process and contributes to the interpretation of microhardness distribution patterns and corresponding mechanisms in various regions of welded joints under different processing conditions. [ABSTRACT FROM AUTHOR]

We first determine the structure of the power digraphs of completely 0-simple semigroups, and then some properties of their power graphs are given. As the main result in this paper, using Cameron and Ghosh's theorem about power graphs of abelian groups, we obtain a characterization that two G 0 -normal completely 0-simple orthodox semigroups S and T with abelian group H -classes are isomorphic based on their power graphs. We also present an algorithm to determine that S and T are isomorphic or not. [ABSTRACT FROM AUTHOR]

Three-dimensional (3D) phononic topological insulators (TIs) featuring two-dimensional (2D) surface states and one-dimensional (1D) hinge states have opened up a new route for multi-dimensional robust wave transport, providing unprecedented methods for integrated acoustic sensors and energy harvesting devices. However, aiming at the elastic 3D phononic TI with gapless surface states and hinge states, the realization of elastic 3D phononic TIs with gapless surface states and hinge states is a significant challenge due to the complicated multi-mode polarization of elastic waves in 3D structures. In this study, we demonstrate an elastic 3D phononic TI with a Dirac hierarchy by elaborately operating the corresponding spatial symmetries of the chiral honeycomb lattice. First, a 3D double Dirac cone of elastic wave can be achieved by doubling the lattice along the out-of-plane direction to fold two iso-frequency Weyl points. The topological phase transitions and 2D gapless two-fold Dirac surface states of elastic wave are realized by breaking the half-lattice spatial translation symmetry. Subsequently, based on the Brillouin zone folding along the in-plane direction, the 2D gapless two-fold surface Dirac cones are folded into four-fold surface Dirac cones. Finally, by inducing the relative radius of adjacent holes to break the in-plane spatial inversion symmetry, the fourfold surface Dirac cones are gapped and associated with a surface state inversion, in which the gapless 1D hinge Dirac dispersion is achieved. This research offers a route for engineering the hierarchies of TIs in 3D elastic wave systems and provides new possibilities for designing 3D ultrasonic devices with unconventional functions. [ABSTRACT FROM AUTHOR]

In mammalian societies, dominance hierarchies translate into inequalities in health, reproductive performance and survival. DNA methylation is thought to mediate the effects of social status on gene expression and phenotypic outcomes, yet a study of social status-specific DNA methylation profiles in different age classes in a wild social mammal is missing. We tested for social status signatures in DNA methylation profiles in wild female spotted hyenas (Crocuta crocuta), cubs and adults, using non-invasively collected gut epithelium samples. In spotted hyena clans, female social status influences access to resources, foraging behavior, health, reproductive performance and survival. We identified 149 differentially methylated regions between 42 high- and low-ranking female spotted hyenas (cubs and adults). Differentially methylated genes were associated with energy conversion, immune function, glutamate receptor signalling and ion transport. Our results provide evidence that socio-environmental inequalities are reflected at the molecular level in cubs and adults in a wild social mammal. An epigenetic study on free-ranging spotted hyenas (Crocuta crocuta) suggests that genes are differentially methylated between high-ranking and low-ranking females (cubs and adults) which may reflect rank-specific differences in access to resources. [ABSTRACT FROM AUTHOR]

Surrogate-assisted evolutionary algorithms (SAEAs) are popular for solving expensive optimization problems. However, most existing SAEAs are designed for solving single-objective or multiobjective optimization problems with two or three objectives. Few works had been reported to deal with expensive many-objective optimization problems with more than three objectives because of two difficulties. One is the curse of dimensionality caused by many-objective problems, and the other is the fewer computational resources available in a limited time for expensive optimization problems. Since an effective selection method can better solve the many-objective optimization problems, high-efficiency search and accurate model can save computational resources for expensive optimization problems, this paper proposes a diverse/converged individual competition algorithm, which owns a novel diverse/converged individual competition selection mechanism, a hybrid search mechanism, and a segmentation approach. The diverse/converged individual competition selection mechanism maintains a good balance between the convergence and diversity of the selected solutions for solving many-objective optimization problems. The hybrid search mechanism performs a memetic search and genetic search at different stages of the evolution process to further generate superior solutions. The segmentation approach uses two different populations with small numbers to build two surrogate models which will predict different areas, and it can improve the accuracy of the prediction. The proposed algorithm is compared with several state-of-art algorithms on widely used benchmark functions. The experimental results show that the proposed algorithm performs significantly better than the compared algorithms. [ABSTRACT FROM AUTHOR]

We first obtain several subdirect product decompositions of additively regular semirings by constructing several pairs of generalized factor congruences. Next, we define and study several additively regular semiring varieties by congruence openings and closure congruences. Moreover, as an application, we obtain several pullback product decompositions of additively regular band semirings. Finally, we establish order embedding theorems on the poset of subvarieties of the additively regular semiring e-variety A R . [ABSTRACT FROM AUTHOR]

We reviewed the literature on the prevalence of small intestinal bacterial overgrowth (SIBO) after Roux-en-Y gastric bypass (RYGB). Eight studies examining 893 patients were included. The mean age of the patients was 48.11 ± 4.89 years. The mean BMI before surgery and at the time of SIBO diagnosis was 44.57 ± 2.89 kg/m2 and 31.53 ± 2.29 kg/m2, respectively. Moreover, the results showed a 29% and 53% prevalence of SIBO at < 3-year and > 3-year follow-up after RYGB, respectively. Symptoms included abdominal pain, diarrhea, bloating, nausea, vomiting, constipation, soft stool, frequent defecation, flatulence, rumpling, dumping syndrome, and irritable bowel syndrome. SIBO is prevalent after RYGB; digestive symptoms should prompt the consideration of SIBO as a potential etiology. Antibiotic therapy has proven to be therapeutic. [ABSTRACT FROM AUTHOR]

Objective: A 32-year-old female was diagnosed with unexplained primary infertility for 10 years. She had roughly normal basal hormone levels, but her basal follicle-stimulating hormone (FSH) levels were elevated. In addition, the level of anti-Mullerian hormone was within the normal range, and she had undergone two failed oocyte collection attempts. We aimed to investigate the genetic cause of female infertility in patients with impaired ovarian folliculogenesis. Methods: Genomic DNA was extracted from the peripheral blood of the patient and her family members. Whole-exome sequencing was performed on the patient, and TBPL2 mutations were identified and confirmed by Sanger sequencing. The Exome Aggregation Consortium (ExAC) Browser and Genome Aggregation Database (gnomAD) Browser Beta were used to search the allele frequencies of the variants in the general population. The harmfulness of the mutations was analyzed by SIFT, Mutation Taster, and CADD software. Result: One novel mutation, c.802C > T (p. Arg268Ter), and one known variant, c.788 + 3A > G (p. Arg233Ter), in TBPL2 were identified in the infertile family. Compound heterozygous mutations in TBPL2 may be the cause of impaired ovarian folliculogenesis, failure of superovulation, and infertility. Conclusions: We identified compound heterozygous mutations in TBPL2 that caused impaired ovarian folliculogenesis, failure of superovulation, and infertility in patients. These findings suggest an important role for compound heterozygous mutations in TBPL2 and expand the mutational spectrum of TBPL2, which might provide a new precise diagnostic marker for female infertility. [ABSTRACT FROM AUTHOR]

Association of distinct inflammatory profiles with short-term mortality is little known in type A aortic dissection (TAAD). Latent class analysis was used to identify distinct inflammatory profiles based on leukocyte, neutrophils, monocyte, lymphocytes, platelet, fibrinogen, d-dimer, neutrophils-lymphocyte ratio, platelet-lymphocyte ratio, and lymphocyte-monocyte ratio. We identified 193 patients with median age of 56 (IQR 47–63) years and 146 males. Patients were divided as hyper-inflammatory profiles (84 [43.5%]) and hypo-inflammatory profiles (109 [56.5%]). Although baseline characteristics were not different, hyper-inflammatory patients had higher 6-month mortality (20 [23.8%] vs. 11 [10.1%]; P = 0.014) and 30-day mortality (18 [21.4%] vs. 9 [8.3%], P = 0.009) than hypo-inflammatory patients. After adjustment for potential confounders, hyper-inflammatory profiles remain associated with higher risk of 6-month mortality than hypo-inflammatory profiles (adjusted OR 2.427 [95%CI 1.154, 5.105], P = 0.019). Assessment of preoperative inflammatory profiles adds clarity regarding the extent of inflammatory response to TAAD aetiopathologies, highlighting individual anti-inflammatory pharmacotherapy for TAAD. ClinicalTrials.gov Identifier: NCT04398992. [ABSTRACT FROM AUTHOR]

The near-Earth (within ∼100 pc) supernova explosions in the past several million years can cause the global deposition of radioactive elements (e.g., 60Fe) on Earth. The remnants of such supernovae are too old to be easily identified. It is therefore of great interest to search for million-year-old near-Earth neutron stars or black holes, the products of supernovae. However, neutron stars and black holes are challenging to find even in our Solar neighbourhood if they are not radio pulsars or X-ray/γ-ray emitters. Here we report the discovery of one of the nearest (127.7 ± 0.3 pc) neutron star candidates in a detached single-lined spectroscopic binary LAMOST J235456.73+335625.9 (hereafter J2354). Utilizing the time-resolved ground-based spectroscopy and space photometry, we find that J2354 hosts an unseen compact object with Minv being 1.4–1.6 M⊙. The follow-up Swift ultraviolet (UV) and X-ray observations suggest that the UV and X-ray emission is produced by the visible star rather than the compact object. Hence, J2354 probably harbours a neutron star rather than a hot ultramassive white dwarf. Two-hour exceptionally sensitive radio follow-up observations with Five-hundred-meter Aperture Spherical radio Telescope fail to reveal any pulsating radio signals at the 6σ flux upper limit of 12.5 µJy. Therefore, the neutron star candidate in J2354 can only be revealed via our time-resolved observations. Interestingly, the distance between J2354 and our Earth can be as close as ∼ 50 pc around 2.5 million years (Myrs) ago, as revealed by the Gaia kinematics. Our discovery demonstrates a promising way to unveil the hidden near-Earth neutron stars in binaries by exploring the optical time domain, thereby facilitating understanding of the metal-enrichment history in our Solar neighbourhood. [ABSTRACT FROM AUTHOR]

Food safety is a critical issue that is closely related to people's health and safety. As a simple, rapid, and sensitive detection technique, surface-enhanced Raman scattering (SERS) technology has significant potential for food safety detection. Recently, researchers have shown a growing interest in utilizing silent region molecules for SERS analysis. These molecules exhibit significant Raman scattering peaks in the cellular Raman silent region between 1800 and 2800 cm−1 avoiding overlapping with the SERS spectrum of biological matrices in the range 600–1800 cm−1, which could effectively circumvent matrix effects and improve the SERS accuracy. In this review, the application of silent region molecules-based SERS analytical technique for food safety detection is introduced, detection strategies including label-free detection and labeled detection are discussed, and recent applications of SERS analysis technology based on molecules containing alkyne and nitrile groups, as well as Prussian blue (PB) in the detection of pesticides, mycotoxins, metal ions, and foodborne pathogens are highlighted. This review aims to draw the attention to the silent region molecules-based SERS analytical technique and to provide theoretical support for its further applications in food safety detection. [ABSTRACT FROM AUTHOR]

To ensure the safety of underground mining activities and effectively protect the surface production facilities and houses of the nearby residents, the ground movement caused by the sublevel caving method needs to be studied. In this work, the failure behaviors of the surface and drift of the surrounding rock were investigated based on the results of in situ failure investigations, monitoring data, and engineering geological conditions. The results were then combined with theoretical analysis to reveal the mechanism responsible for the movement of the hanging wall. Driven by the in situ horizontal ground stress, horizontal displacement plays an imperative role in both the movement of the ground surface and underground drifts. Accelerated movement is found to occur in the ground surface which coincides with the occurrence of drift failure. Failure occurs in the deep rock masses and then gradually propagates to the surface. The steeply dipping discontinuities are the main reason for the unique ground movement mechanism in the hanging wall. As steeply dipping joints cut through the rock mass, the rock surrounding the hanging wall can be modeled as cantilever beams subjected to in situ horizontal ground stress and lateral stress due to caved rock. This model can be used to obtain a modified formula for toppling failure. Also, a mechanism of fault slipping was proposed, and the condition required for fault slipping was obtained. Based on the failure mechanism of steeply dipping discontinuities, the ground movement mechanism was proposed considering the horizontal in situ ground stress and caved rock mass: slippage of fault F3, slippage of fault F4, and toppling of rock columns. Based on the unique ground movement mechanism, the goaf surrounding rock mass could be divided into six zones: a caved zone, a failure zone, a toppling-slipping zone, a toppling-deformation zone, a fault-slipping zone, and a movement-deformation zone. [ABSTRACT FROM AUTHOR]

In this paper, the multiple parametric Marcinkiewicz integral operators with mixed homogeneity along surfaces are studied. The Lp-mapping properties for such operators are obtained under the rather weakened size conditions on the integral kernels both on the unit sphere and in the radial direction. The main results essentially improve and extend certain previous results. [ABSTRACT FROM AUTHOR]

The nature of molecule-electrode interface is critical for the integration of atomically precise molecules as functional components into circuits. Herein, we demonstrate that the electric field localized metal cations in outer Helmholtz plane can modulate interfacial Au-carboxyl contacts, realizing a reversible single-molecule switch. STM break junction and I-V measurements show the electrochemical gating of aliphatic and aromatic carboxylic acids have a conductance ON/OFF behavior in electrolyte solution containing metal cations (i.e., Na+, K+, Mg2+ and Ca2+), compared to almost no change in conductance without metal cations. In situ Raman spectra reveal strong molecular carboxyl-metal cation coordination at the negatively charged electrode surface, hindering the formation of molecular junctions for electron tunnelling. This work validates the critical role of localized cations in the electric double layer to regulate electron transport at the single-molecule level. A common approach to design single-molecule switch is to use molecular backbones in response to external stimulus, but often requires complex organic synthesis. Here, Tong et al. show how to in situ control of the molecule-electrode contact using electrochemical gating to realize a reversible switch. [ABSTRACT FROM AUTHOR]

The Wangjiadashan area in Suizhou-Zaoyang region of Hubei Province in the Tongbai-Dabie orogenic belt hosts important copper-gold deposits and contains a large number of quartz syenite porphyry dykes, occurring mostly along the NEE-trend faults. In this study, we used LA-ICP-MS zircon U-Pb dating method and obtained an age of 143.6 ± 1.4 Ma, which represents the emplacement of these quartz syenite porphyry dykes was at the Yanshanian, but it was slightly earlier than the previously reported ages (139–135 Ma) for granites widespreading in Suizao area. The geochemical data of the Wangjiadashan quartz syenite porphyry show high K2O, CaO, Na2O and Al2O3 contents but extremely low MgO contents (0.01 wt.%–0.46 wt.%). The geochemical characteristics indicate that these quartz syenite porphyry dykes belong to the typical C-type adakite and were possibly formed in the post-collisional environment. Multi-isotopic (Sr-Nd-Pb-Hf) analyses indicate that these quartz syenite porphyry dykes were originated from crust without distinct mantle materials involved. It is suggested that the Wangjiadashan quartz syenite porphyry was generated from partial melting of the thickened lower continental crust, and garnet but no plagioclase was left as residual phase. Compared with the widespread granites of the Tongbai area, the Wangjiadashan quartz syenite porphyry formed earlier and derived from more juvenile and K-rich lower crust, while they all belong to intensive magmatism concentrated during the Early Cretaceous epoch in the Tongbai area. [ABSTRACT FROM AUTHOR]

Preterm premature rupture of membranes (pPROM) is a common pregnancy disease closely related to inflammation. The formyl peptide receptor 2 (FPR2), a member of the G protein-coupled receptor family involved in defense responses, inflammation, and disturbances in glucose and lipid metabolism, is associated with pregnancy diseases. Lipoxin A4 (LXA4) can activate FPR2 and inhibit the inflammatory signals. Exosomes derived from mesenchymal stem cells are good materials for anti-inflammatory and tissue repair. This study aims to investigate the anti-inflammatory and tissue repair effects of the combined application of exosomes derived from human umbilical cord mesenchymal stem cells and FPR2 agonist LXA4. In this study, LPS was used to establish the inflammation model of pregnant mice and HTR8 cells, and LXA4 and exosome treatment were carried out to observe the fetal membranes' tissue repair. The scanning and transmission electron microscopy of fetal membrane tissue indicated that the structure of pPROM tissue was disordered, and the cell gap was significantly increased. The results of the inflammatory mice model suggested that LPS can cause damage to the fetal membrane structure. LXA4 combined with exosome treatment can inhibit the production of MMP2 and MMP9, and promote neovascularization by inhibiting the p38 MAPK/Nuclear factor kB p65 (NFkB) pathway in the inflammation model of HTR8 cells and pregnant mice, thus helping to control inflammation and tissue repair. [ABSTRACT FROM AUTHOR]

To ensure the production of food crops, a series of cryptolepine derivatives were synthesised, after which their antibacterial activities and mechanism of action against three plant pathogens were investigated. Our bioassay results indicated that most of the target compounds displayed potent inhibitory effects against Xanthomonas oryzae (X. oryzae) and Xanthomonas axonopodis pv. citri (X. axonopodis pv. c.). Remarkably, compound 9 exhibited the best in vitro antibacterial activity against X. oryzae, with a minimum inhibitory concentration (MIC) value of 0.78 μg·mL–1. Compound 2 exhibited the best in vitro antibacterial activity against X. axonopodis pv. c., with an MIC value of 0.39 μg·mL–1. These activities were superior to those of copper quinolate (MIC = 6.25, 25 μg·mL–1) and thiodiazole copper (MIC = 100, 200 μg·mL–1) against X. oryzae and X. axonopodis pv. c. In vivo experiments demonstrated the promising applicability of compound 9 for the control of rice bacterial infections. Furthermore, compound 9 was selected as a candidate to conduct preliminary analyses of the antibacterial mechanisms of cryptolepine derivatives. Scanning electron microscopy and transmission electron microscopy observations, extracellular polysaccharide production, biofilm formation, transcriptomic, quantitative reverse transcription-polymerase chain reaction analyses, and molecular docking assays were performed. Collectively, our findings demonstrated that compound 9 might act via multifarious mechanisms to down-regulate virulence factors and cause cell death. [ABSTRACT FROM AUTHOR]

Therefore, an alternate dissection and stapling technique were developed to minimize the risk of bleeding or splenic ischemia in patients with larger spleens. In our study, we identified certain bariatric patients with larger spleens, where the posterior aspect of the fundus or the left crus ligament closely adhered to the spleen (Fig. Moraes et al. categorized the splenic artery based on origin and ramification, revealing that 95.47% of patients presented with the bifurcation of the terminal division of the splenic artery, while 4.53% of patients presented with trifurcation. [Extracted from the article]

The Miaoya carbonatite complex in the South Qinling Orogen hosts one of the largest REE-Nb deposits in China. The origin and evolution of REE enrichment in this Silurian intrusion have been extensively studied, whereas Nb mineralization remains less well understood. Here, we report detailed mineralogical and geochemical data on diverse Nb-bearing minerals from the Miaoya carbonatite to explain the development of Nb mineralization in these rocks. Ferrocolumbite is the dominant Nb mineral, which occurs principally as an alteration product of the earlier-crystallized Nb phases (uranopyrochlore, betafite, and fersmite). The ferrocolumbite varieties (Clb-1, Clb-2, Clb-3) inherited some compositional characteristics of its precursors, in particular a trend of decreasing Ta2O5 and UO2 from Clb-1 to Clb-3, which mimics the Ta-U depletion trend from uranopyrochlore to betafite and fersmite. Varieties Clb-1 and Clb-2 and associated calcite and altered uranopyrochlore show evidence of hydrothermal overprint such as positive Eu anomaly. Ferrocolumbite Clb-2 shows slightly higher Eu/Eu* and Zr/Hf ratios and contains fewer relicts of its precursor mineral in comparison with Clb-1, possibly indicating local enrichment of F in the hydrothermal system. Calcite associated with Clb-3 and fersmite shows a trace element signature characteristic of igneous carbonates, suggesting that this mineral paragenesis is least affected by metasomatic overprint with no contribution from external fluids. The study of the Miaoya REE-Nb deposit shows that late-stage metasomatism of carbonatites does not significantly enhance Nb grade in contrast to that of REE mineralization and leads to the formation of a secondary Nb paragenesis with specific trace element characteristics. [ABSTRACT FROM AUTHOR]

The Maogongdong deposit is located in the giant Dahutang W-Cu-(Mo) ore field, northern Jiangxi Province, South China. It is mainly a vein-type deposit, characterized by early W and late Cu-Mo mineralization, and temporally and spatially associated with Late Mesozoic S-type muscovite granites emplaced into a Neoproterozoic granodiorite batholith and the Shuangqiaoshan Group metasedimentary rocks. Fluid inclusions and H–O isotopes suggest that the early ore-forming fluids of the Maogongdong deposit are mainly magmatic water with relatively high temperature (270–410 °C) and moderate-to-low salinity, while the late ore-forming fluids are mixed with meteoric water, with medium-to-low temperature (160–270 °C) and low salinity. Infrared and conventional microthermometric studies of fluid inclusions of the main tungsten mineralization stage show that the homogenization temperatures of primary fluid inclusion assemblages in wolframite (325 to 355 °C) are about 20 °C higher than those of coexisting scheelite and generally 40 °C higher than those in quartz. The δ34S values of sulfides (− 5.2 to − 1.3 ‰) in the sulfide stage are slightly lower than the magmatic sulfur (− 1.7 to 0.6 ‰) in the pre-ore stage, most likely due to an increase in oxygen fugacity. The low carbon isotope values (− 26.2 to − 15.5 ‰) of fluid inclusions in the tungsten mineralization stage show that a large amount of organic carbon was added before mineralization. Fluid cooling and pressure decrease are the main factors of tungsten ore precipitation, while local boiling may also make a contribution. Mixing of the different fluids led to the formation of copper and molybdenum ores. [ABSTRACT FROM AUTHOR]

In this study, we prepared unentangled and slightly entangled poly(L-lactic acid) telechelic ionomer samples (Mn=5 and 16 kg/mol) based on sodium sulfonate groups. The telechelic samples exhibit extremely slow crystallization kinetics below the melting temperature Tm and above the glass transition temperature Tg, which enables us to examine the linear viscoelasticity of the ionomer melt samples therein. The application of either the shear flow (at 85 °C) or elongational flow (between 70 and 90 °C) strongly accelerates the crystallization, leading to strong strain hardening and formation of highly oriented α crystals. Depending on the relative average rates of the strain-induced dissociation and strain-induced crystallization, the stress evolution can be classified into two cases, and the critical work for strain-induced crystallization is higher in case where the strain-induced dissociation occurs earlier than the strain-induced crystallization. [ABSTRACT FROM AUTHOR]

Lithium is one of the important strategic energy metals, which is in short supply in China. There are three major types of lithium deposits: brine and salt lake type, highly differentiated granite or pegmatite type, and carbonate-clay type. In recent years, some new types of lithium deposits have also begun to receive great attention and subject recent research. There are many crypto-explosive breccia pipe type deposits in the world, including copper, gold, lead, zinc, tungsten and tin deposits, but little is known about this type of lithium deposit. This paper introduces the latest research results of the Weilasituo Sn−Li−Rb polymetallic deposit in Inner Mongolia (NE China), which occurs in the middle-southern section of the Great Xing'an Range metallogenic belt. A remarkable feature of this deposit is the coexistence of various mineralization types, including granite type Rb and Sn−Zn, hydrothermal crypto-explosive breccia pipe type Li−Rb, quartz vein type Sn−Zn and sulfide vein type Pb−Zn−Ag mineralization. Among them, hydrothermal crypto-explosive breccia pipe type Li-Rb deposit is currently very rare at home and abroad, which is likely a new type of rare metal deposit that worthy of our attention. This paper systematically summarizes the geology, alteration and mineralization, geochemistry, isotopes and geochronology of the Weilasituo deposit, and establishes a new petrogenic and metallogenic model. [ABSTRACT FROM AUTHOR]

The Hermyingyi quartz vein–type W–Sn deposit is one of the major tungsten and tin producers in Myanmar. It comprises a series of north-trending wolframite-cassiterite-bearing quartz veins mainly hosted in the Late Cretaceous monzogranite which intruded into Paleozoic metasedimentary rocks. Conventional fluid inclusion and infrared microthermometric results reveal that homogenization temperatures decrease from the wolframite-cassiterite stage (stage I, 239–348 °C) through the sulfide stage (stage II, 222–248 °C) to the barren quartz vein stage (stage III, 174–218 °C), whereas salinities vary in a similar range for stage I (1.4–11.7 wt% NaCl equiv.) and II (1.7–11.3 wt% NaCl equiv.) and are slightly lower in stage III (0.7–5.9 wt% NaCl equiv.). Fluid inclusions in wolframite and cassiterite from stage I have similar salinities but distinctly higher (~ 60 °C) temperatures compared to those in coexisting quartz. The δ18Ofluid (3.3 to 7.0‰) and δD (− 76 to − 61‰) values of quartz, wolframite, and cassiterite indicate a dominantly magmatic fluid in stage I, while decreasing values of quartz in stage II (δ18Ofluid = 1.3 to 1.8‰, δD = − 81 to − 71‰) and III (δ18Ofluid = − 3.1 to − 1.6‰, δD = − 89 to − 73‰) show a trend of cooling and dilution by meteoric water. The negative and increasing δ13Cco2 values (from − 20.5 to − 4.9‰) of quartz fluid inclusions from early to late stages imply that organic carbon was added to the magmatic fluid through fluid-rock interaction in stage I, consumed with time and almost exhausted in stage III. The δ34S values (1.6 to 7.9‰) of sulfides coupled with the comparable Pb isotope data of the monzogranite (206Pb/204Pb = 18.572 − 18.784, 207Pb/204Pb = 15.749 − 15.760, 208Pb/204Pb = 39.265 − 39.333) and sulfides (206Pb/204Pb = 18.655 − 18.749, 207Pb/204Pb = 15.737 − 15.768, 208Pb/204Pb = 39.258 − 39.368) suggest igneous sources of sulfur and lead. By combining these results, we propose that fluid-rock interaction and fluid cooling have been responsible for the deposition of wolframite and cassiterite in the Hermyingyi deposit. [ABSTRACT FROM AUTHOR]

The hot deformation behavior of spray-formed 7055 aluminum alloy was investigated using a thermo-mechanical simulator by a series of isothermal and constant strain-rate compression tests. These tests were at deformation temperatures ranging from 653 to 713 K and strain rates ranging from 0.1 to 15s−1. The microstructure characteristics of these deformed samples were examined by optical microscope (OM) and electron back-scattered diffraction (EBSD) techniques. The material flow patterns and relevant microstructural analyses indicated that specific thermo-mechanical conditions including the Zener-Hollomon parameter, temperature, and strain, determined the onset and degree of obvious dynamic recrystallization (DRX) behavior. A partially recrystallized grain microstructure was observed and enhanced the flow softening especially at low Zener-Hollomon values. The influence of different hot deformation conditions on the material flow behavior and the evolution of microstructure was confirmed. A new three-stage constitutive equation, accompanied by a microstructure evolution model, was developed to predict the flow stress of sprayed-formed 7055 aluminum alloy and the corresponding characteristics of DRX transformation during the hot deformation process. The predicted performance was evaluated by experimental data and showed good accuracy. [ABSTRACT FROM AUTHOR]

The southern Myanmar tin ore district is an important part of the well-known Southeast Asia tin belt (SATB), and hosts numerous economically important primary tin-tungsten ore deposits. However, the timing of formation of these deposits is unclear due to the scarcity of robust age data. The tectonic setting of tin mineralization in this area also needs to be further constrained. Most of the primary tin-tungsten ore deposits in southern Myanmar are typical hydrothermal quartz vein–type, with cassiterite and wolframite as the main ore minerals. Here, we present in situ U–Pb ages of cassiterite and wolframite from nine granite-related hydrothermal Sn–W deposits in southern Myanmar. Cassiterite samples from the Hermyingyi, Thitkhatoe, Thaling Taung, Kalonta, Taungphila, Pagaye, Bawapin, Kanbauk, and Letha Taung deposits yield common lead-corrected weighted mean 206Pb/238U ages of 61.6 ± 0.8 Ma, 61.9 ± 0.6 Ma, 60.4 ± 0.9 Ma, 63.0 ± 0.6 Ma, 62.9 ± 0.6 Ma, 69.5 ± 0.5 Ma, 63.6 ± 0.6 Ma, 61.3 ± 0.6 Ma, and 84.9 ± 0.5 Ma, respectively. Wolframite samples collected from these deposits also yield consistent ages with the cassiterite samples. These ages, combined with available tin mineralization ages from other deposits in the western part of the SATB, define three epochs of Sn metallogeny related to three contrasting geodynamic settings: (1) Early Cretaceous (~ 125–110 Ma) mineralization is related to post-collision slab break-off after collision between the West Burma terrane and the Sibumasu-Tengchong terrane; (2) Late Cretaceous to Paleocene (~ 90–60 Ma) mineralization developed in an Andean-type accretionary setting during subduction of the Neo-Tethys oceanic lithosphere; (3) Early Eocene (~ 50–40 Ma) mineralization may have formed in a post-collision setting after the India-Asia collision. [ABSTRACT FROM AUTHOR]

The SLC25A32 dysfunction is associated with neural tube defects (NTDs) and exercise intolerance, but very little is known about disease-specific mechanisms due to a paucity of animal models. Here, we generated homozygous (Slc25a32Y174C/Y174C and Slc25a32K235R/K235R) and compound heterozygous (Slc25a32Y174C/K235R) knock-in mice by mimicking the missense mutations identified from our patient. A homozygous knock-out (Slc25a32−/−) mouse was also generated. The Slc25a32K235R/K235R and Slc25a32Y174C/K235R mice presented with mild motor impairment and recapitulated the biochemical disturbances of the patient. While Slc25a32−/− mice die in utero with NTDs. None of the Slc25a32 mutations hindered the mitochondrial uptake of folate. Instead, the mitochondrial uptake of flavin adenine dinucleotide (FAD) was specifically blocked by Slc25a32Y174C/K235R, Slc25a32K235R/K235R, and Slc25a32−/− mutations. A positive correlation between SLC25A32 dysfunction and flavoenzyme deficiency was observed. Besides the flavoenzymes involved in fatty acid β-oxidation and amino acid metabolism being impaired, Slc25a32−/− embryos also had a subunit of glycine cleavage system—dihydrolipoamide dehydrogenase damaged, resulting in glycine accumulation and glycine derived-formate reduction, which further disturbed folate-mediated one-carbon metabolism, leading to 5-methyltetrahydrofolate shortage and other folate intermediates accumulation. Maternal formate supplementation increased the 5-methyltetrahydrofolate levels and ameliorated the NTDs in Slc25a32−/− embryos. The Slc25a32K235R/K235R and Slc25a32Y174C/K235R mice had no glycine accumulation, but had another formate donor—dimethylglycine accumulated and formate deficiency. Meanwhile, they suffered from the absence of all folate intermediates in mitochondria. Formate supplementation increased the folate amounts, but this effect was not restricted to the Slc25a32 mutant mice only. In summary, we established novel animal models, which enabled us to understand the function of SLC25A32 better and to elucidate the role of SLC25A32 dysfunction in human disease development and progression. [ABSTRACT FROM AUTHOR]

To study the hysteretic behavior of specimens of square concrete-filled CFRP-steel tube under different influencing factors, a total of 12 specimens are designed, and the failure modes and P-Δ curves are investigated from experimental test. The simulation software ABAQUS is used to build the numerical model to study P-Δ curves and deformation mode of specimens. Based upon the tri-linear model, the restoring force model of square concrete-filled CFRP-steel tube is proposed, and the results of the tri-linear model are compared with those of the finite element model. The test results reveal that P-Δ curves of specimens are plump, and all specimens demonstrate excellent hysteretic behavior. The P-Δ curves, the skeleton curves and the deformation mode of specimens are reproduced by finite element model. The accuracy of the simulation results is verified by comparing numerical results with experimental results. In terms of the restoring force model, a satisfactory agreement is achieved by comparing predicted results of tri-linear model with finite element simulations. [ABSTRACT FROM AUTHOR]

The Zhaiping Ag–Pb–Zn vein deposit in the Coastal Volcanic Belt of southeastern China, which resulted from subduction of the paleo-Pacific oceanic lithosphere beneath the South China Block, is hosted by Early Cretaceous sub-volcanic rocks (rhyolite porphyry) and younger granite porphyry and quartz porphyry. Three generations of veins have been recognized: (i) pre-ore quartz + pyrite, (ii) syn-ore silver + pyrite + pyrrhotite + base metal sulfides + quartz + sericite, and (iii) post-ore quartz + calcite + fluorite veins. Rubidium–Sr dating of syn-ore pyrite yielded an isochron age of 132.2 ± 2.1 Ma (2σ, MSWD = 2.0, n = 4), which is roughly coincidental with the age of the granite porphyry and quartz porphyry (zircon U–Pb age: ca. 133 Ma). The age data, together with Pb, S, H, and O isotopic compositions, indicate a close temporal and possibly genetic relationship between mineralization and porphyry magmatism at Zhaiping. Geochemical and isotope data demonstrate that the Zhaiping sub-volcanic rocks were derived from partial melting of Proterozoic crustal sources and underwent fractionation of feldspars, monazite, and/or allanite. The 87Sr/86Sr ratios of pre-ore (Aph1) and syn-ore (Aph2) stage apatite are in the ranges of 0.71350 to 0.71441 and 0.71260 to 0.71328, respectively, which are distinct from those of the sub-volcanic intrusive rocks (0.7119–0.7125). The Sr isotope signature, together with lower fluid temperatures (< 360 °C) relative to typical magmatic fluid, points at addition of an external fluid. It is suggested that the sub-volcanic intrusion acted as a heat source that drove the dehydration of, and subsequent fluid circulation within, the host rocks. Lower 87Sr/86Sr ratio but higher Sr content of Aph2 relative to Aph1 possibly indicates continuous fluid–rock interaction and progressive decomposition of feldspar in the host rocks, thus supplying large amounts of Sr and probably Pb to the ore fluid. [ABSTRACT FROM AUTHOR]

The Daye district represents one of the largest concentrations of skarn deposits in eastern China. There are two major types of skarn deposits (Fe skarn vs. Cu skarn) within this district, both genetically related to late Mesozoic high-K calc-alkaline granitoids. In this study, we present in situ compositional and Sr–Nd isotopic investigations of apatite from granitoids associated with Fe skarn and Cu skarn deposits to put constraints on the magma source, evolution, and volatile composition, which provide significant new insights into the genesis of the two contrasting mineralization styles in the Daye district. Apatite from granitoids related to Cu skarns and Lingxiang Fe skarn has εNd(t) values of − 8 to − 4, similar to that of the contemporaneous mafic rocks in the Daye district, which were dominantly derived from an enriched lithospheric mantle source. Apatite in granitoids associated with the Chengchao Fe skarn has lower εNd(t) values of − 15 to − 9, suggesting larger degrees of contaminations from ancient lower crust materials. Fractionation models based on apatite Sr/Y and Eu/Eu* ratios, suggest that magmas related with the Cu skarns have experienced amphibole-dominated fractionation under high pressure and hydrous conditions, whereas those associated with Fe skarns have undergone plagioclase-dominated fractionation at relatively low pressure and dry conditions. Based on results of apatite compositional analysis and apatite-melt partitioning data, the estimated magma Cl contents for the Fe skarn range from 3260 to 13,940 ppm, significantly higher than those for the Cu skarn (Cl = 430–5990 ppm). Apatite from Fe skarn-related intrusions has (87Sr/86Sr)t ranging from 0.7073 to 0.7082, whereas the variety from Cu skarn-related intrusions displays lower (87Sr/86Sr)t of 0.7054–0.7061. These Sr isotope data, combined with whole-rock S isotopes of this study and previous investigations suggest that the Fe skarn-related intrusions have assimilated larger amount of evaporite-bearing carbonate during magma ascent and emplacement. The assimilation process may have not only promoted magmatic water exsolution but also provided sufficient amount of Cl− and SO 4 2 - , which facilitated effective complexation and transportation of Fe2+ and subsequent oxidization of ferrous Fe to precipitate magnetite, respectively. We suggest that evaporite assimilation into the granitoid magmas has played a crucial role in the large-scaled Fe skarn mineralization in the Daye district. This study highlights that apatite is a sensitive petrogenetic-metallogenic indicator for granitoids and thus can be useful in mineral exploration. [ABSTRACT FROM AUTHOR]

The Manzhouli–Xin Barag Right Banner area, located in the southwestern Erguna Massif, is characterized by the distribution of a large volume of Mesozoic volcanic rocks and many polymetallic deposits. However, the tectonic setting of this area during the Late Mesozoic remains controversial. In this study, zircon U–Pb ages range from 142.8 ± 1.8 to 140.4 ± 1.6 Ma for the alkali basalt from the Meiletu Formation and 140 ± 0.9 Ma for alkaline rhyolites from the Baiyingaolao Formation, forming a bimodal volcanic rock assemblage. The initial 87Sr/86Sr ratios range from 0.705365 to 0.705674, and the εNd(t) values vary from + 0.55 to + 1.47. The alkaline rhyolites show εHf(t) values ranging from + 5.3 to + 8.6, corresponding to TDM1 and TDM2 ages in the range of 0.48–0.58 Ga and 0.64–0.86 Ga, respectively. Combined with the major and trace element compositions, the Meiletu alkali basalts are characterized by Nb enrichment (averaging 23.6 ppm) and were derived from partial melting of metasomatized subcontinental lithospheric mantle and underwent moderate fractional crystallization of minerals (e.g. olivine, clinopyroxene, apatite, and plagioclase). The alkaline rhyolites show A1-type granite affinity and originated from partial melting of the mafic lower crust accompanied by fractional crystallization. This suite of bimodal volcanic rocks was mainly dominated by the Mongol–Okhotsk tectonic regime, and the Erguna Massif was in a back-arc extensional setting triggered by slab rollback during the Early Cretaceous. [ABSTRACT FROM AUTHOR]

The large Hebaoshan gold deposit (41.5 t Au, average grade: 3.5 g/t) is located in a hitherto poorly documented gold province in the northeastern part of the South China Block. It is hosted by Precambrian metasedimentary rocks that experienced Triassic greenschist- to amphibolite-facies metamorphism. Three hydrothermal stages can be distinguished: quartz + sericite + pyrite + pyrrhotite (stage I), quartz + magnetite + sulfide (stage II), and quartz + carbonate + pyrite + hematite (stage III). Auriferous pyrite samples yielded a Rb-Sr isochron age of 234 ± 3 Ma (2σ, MSWD = 0.24), and ore-related hydrothermal sericite yielded a 40Ar-39Ar plateau age of 226.4 ± 2.0 Ma (2σ, MSWD = 1.01), which are distinctly younger than ca. 430 Ma granitic rocks in the mining district and older than 170–130 Ma granites in the region, ruling out any genetic link between granite emplacement and gold mineralization. The mineralizing fluid system can be described as carbonic-aqueous with low to moderate salinity (2.2–10.1 wt% NaCl equiv.) and medium temperature of 290 to 350 °C (stage I) and 230 to 280 °C (stage II). The δ18O quartz ranges from 13.3 to 15.4 ‰, and the δD values for fluid inclusions in quartz range from − 97 to − 60 ‰. The calcite has C-isotopes ranging from − 6.1 to − 3.8 ‰ and O-isotopes from 2.8 to 13.6 ‰. H-O-C isotope data are consistent with a metamorphic fluid derived from devolatilization of Neoproterozoic basement rocks during regional metamorphism in the Late Triassic Indosinian period. The δ34S values of sulfides for stages I, II, and III are 0.1 to 7.8 ‰, − 10.6 to 5.1 ‰, and − 18.9 to − 14.1 ‰, respectively, indicating an increase in oxygen fugacity during fluid ascent which resulted in more negative sulfur isotope values of sulfides and precipitation of gold. Pyrite separates have 206Pb/204Pb ratios of 17.340 to 17.687, 207Pb/204Pb ratios of 15.539 to 15.604, and 208Pb/204Pb ratios of 37.749 to 38.094. The S-Pb isotope data suggest derivation of S and Pb from the Precambrian metasedimentary country rocks. Auriferous pyrite yielded elevated 3He/4He ratios (0.78–1.46 Ra), which suggest a mantle component as can be expected from fluids derived from a subduction setting. It is concluded that Hebaoshan is an orogenic gold deposit that formed during Triassic flat-slab subduction of the paleo-Pacific plate beneath the South China Block and thus constitutes the first Triassic deposit of this type recognized in the coastal area of Southeast China. [ABSTRACT FROM AUTHOR]

The Dachang Sn-polymetallic ore district in South China is the second largest tin district in the world with a tin reserve of over one million tonnes. Zn-Cu skarn and stratiform, massive, and vein Sn-Pb-Zn ores are all present in this district. This has led to a debate as to whether the Sn orebodies were formed by Cretaceous magmatic-hydrothermal replacement or Devonian submarine exhalative-hydrothermal sedimentation. Here, we present a systematic investigation of the major, trace element, and boron isotopic compositions of different types of tourmaline in the Dachang ore district. Tourmaline disseminated in the Longxianggai granite and pegmatite veins belongs to the schorl series and has high contents of Li, Zn, and Ga. The δ11B value of primary magma of the Longxianggai granite is estimated to be about −13‰, close to the global average δ11B value (−11‰) for S-type granites. Tourmaline from quartz-tourmaline veins in the Longxianggai granite has similar chemical composition to the magmatic tourmaline and likely formed from hydrothermal fluids exsolved from the evolved granitic melt. The δ11B value of the initial hydrothermal fluids is also calculated to be about −13‰. Tourmalines from the skarn and sulfide ores in the Lamo deposit have higher Mg/(Mg+Fe) and lower Na/(Na+Ca) ratios and higher contents of Be, Ge, Sr, and Sn than magmatic tourmaline. These patterns likely reflect input of elements derived from the host Devonian limestone. The δ11B values of the hydrothermal fluids are estimated to be between −13 and −10‰, suggesting evolved magmatic-hydrothermal fluids related to the Longxianggai granite. Tourmalines from the stratiform and vein ores in the Changpo-Tongkeng deposit are extremely Mg-rich and mostly belong to the dravite series. They have high contents of Sc, V, Cr, Sr, and Sn and show positive Eu anomalies. The δ11B values of these B- and Sn-rich fluids are estimated to be between −15 and −10‰, suggesting that the fluids also have a magmatic-hydrothermal origin. These fluids are most likely derived from the same granitic magma source, but may have interacted with the Devonian volcanic rocks. [ABSTRACT FROM AUTHOR]

In this paper, for solving horizontal nonlinear complementarity problem (HNCP), a two-step modulus-based matrix splitting iteration method is established. The convergence analysis of the proposed method is presented. Numerical examples are reported to show the efficiency of the proposed method. [ABSTRACT FROM AUTHOR]

Several gabbro, gabbroic diorite, and diorite intrusions were emplaced in the Neotethyan Urumieh-Dokhtar magmatic arc in the Kahak area of the Zagros Orogen. The plutonic rocks intruded Cenozoic volcanic and pyroclastic succession. U-Pb dating via LA-ICP-MS of zircon yields early to middle Eocene ages of ~53 to 38 Ma for the diorite and gabbroic diorite in Veshnaveh and Naragh areas and Miocene ages of 23 to 20 Ma for gabbroic rocks in the Kerogan and Fordou areas. The Eocene magmatic phase occurred quite possibly as three continuous pulses. The Eocene and Miocene intrusions have negative Nb-Ta anomalies like those of subduction-related magmas. The Pb isotopic compositions show the involvement of subducted sediment in the source of the studied samples. The Eocene intrusions are tholeiitic and enriched in incompatible-trace-elements (especially the HFSE) compared to the Miocene intrusions which are calc-alkaline and have lower concentrations of most incompatible trace elements. Sr-Nd isotopic compositions of the Eocene rocks lie close to the mantle array and near Bulk Silicate Earth, but the Miocene suite is shifted to higher (87Sr/86Sr)i. The higher (87Sr/86Sr)i, along with larger Ba, K, Pb, and Sr anomalies, in the Miocene suite imply more slab fluid input and/or crustal contamination. Apparently, the Eocene mafic magmas formed in slightly metasomatized sub-continental lithospheric mantle (SCLM), whereas the Miocene suite was derived from highly metasomatized, deeper levels of the SCLM. We suggest that slab roll back occurred between the Eocene and Miocene and transferred the location of mantle partial melting to greater depths. [ABSTRACT FROM AUTHOR]

Surface finish is one of the most important quality characteristics of titanium implants in the medical field. In this paper, a laser-assisted thermochemical polishing system based on scanning galvanometer was designed and built for the ultrahigh-precision polishing of titanium. The influence of the laser processing parameters and initial surface roughness of the workpiece on the final polishing results were systematically studied, and the polishing mechanisms were discussed. The results show that the final polishing quality was closely related to the laser pulse energy, spot overlapping rate, scanning times, and properties of the material itself but not to the initial surface roughness of the workpiece. In addition, the laser destroyed the passivation layer on the surface of the workpiece, resulting in direct contact between the titanium and etching solution. On the other hand, it induced the generation of a thermo-electromotive force, which caused the electrochemical corrosion on the workpiece surface, accelerating the dissolution of peaks on the surface of the material. The workpiece surface finish was improved because of the difference between the material dissolution rates of the peaks and valleys. Finally, ultrahigh-precision polishing of a commercially pure titanium surface was achieved using the optimized process parameters. [ABSTRACT FROM AUTHOR]

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Early Cretaceous mafic rocks are first reported in the northern Guangxi region from the western Qin-Hang belt in the interior South China Block. A systematic investigation of zircon U–Pb dating, whole-rock geochemistry, Sm–Nd isotopes and zircon Hf–O isotopes for these mafic rocks reveals their petrogenesis and the mantle composition as well as a new window to reconstruct lithospheric evolution in interior South China Block during Late Mesozoic. Zircon U–Pb dating yielded ages of 131 ± 2 Ma to 136 ± 2 Ma for diabase and gabbro from Baotan area, indicating the first data for Early Cretaceous mafic magmatism in the western Qing-Hang belt. These mafic rocks show calc-alkaline compositions, arc-like trace element distribution patterns, low zircon εHf(t) of − 9.45 to − 6.17 and high δ18O values of + 5.72 to + 8.09‰, as well as low whole-rock εNd(t) values of − 14.27 to − 9.53. These data suggest that the studied mafic rocks are derived from an ancient lithospheric mantle source that was metasomatized during Neoproterozoic subduction. Thus, the occurrence of these mafic rocks indicates a reactivation of Neoproterozoic subducted materials during an extension setting at Late Mesozoic in the western Qin-Hang belt, an old suture zone that amalgamates the Yangtze and Cathaysia blocks. [ABSTRACT FROM AUTHOR]