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In the present work, five compositions in the BaO–MgO–SiO2 ternary system were chosen, and ceramics were prepared using the solid‐state reaction method. Single phases were formed easily for the first four compositions, and BaMgSi3O8 ceramics were found to be a mixture of both BaSi2O5 and MgSiO3, according to X‐ray diffraction results. Among all the compositions, Ba2MgSi2O7 ceramic sintered at 1225°C possesses the highest Qf (Q = 1/dielectric loss = 1/tanδ, f = resonant frequency) value ∼55 010 GHz along with relative permittivity ∼8.0 and temperature coefficient of resonant frequency (TCF) ∼−57.5 ppm/°C. With 3 wt.% BCB (BaO–B2O3–CuO) additions, Ba2MgSi2O7 ceramic was well densified at 950°C with a relative permittivity ∼8.1, Qf value ∼28 920 GHz (at 12.37 GHz) and TCF value ∼‒56.6 ppm/°C. These series ceramics with low relative permittivity values might be good candidates for low‐temperature co‐fire ceramic technology substrate applications. [ABSTRACT FROM AUTHOR]

The poor dispersion of multiwalled carbon nanotubes (MWCNTs) and weak interfacial adhesion of fabric and resin matrix seriously affect the tribological performance of fabric‐reinforcement resin composites. Tannic acid (TA), a plant‐derived compound, which is similar to mussel‐inspired polydopamine, can adhere to various substrates under a weak basic buffer solution. Therefore, in this work, TA‐modified MWCNTs were incorporated into TA functionalized fabric composite to improve the tribological performance of the fabric composite. The results indicate that the MWCNTs and fabric were successfully modified with TA. The wear tests revealed that the TA‐MWCNTs reinforcement TA‐fabric resin composites exhibited the best tribological performance, in which the friction coefficient and volume wear rate decreased by 16.9% and 40%, respectively, compared with pristine fabric composite. The favorable interfacial bonding between fabric and resin is beneficial to the friction force transfer to the load‐bearing fabric, decreasing the stress focus and thus reducing the damage to composite materials. Meanwhile, the good dispersion of MWCNTs contributes to the excellent lubrication performance. This simple and eco‐friendly method of treating fillers with TA provides a new approach to achieve high‐performance tribological materials. [ABSTRACT FROM AUTHOR]

The slow kinetic process of the oxygen evolution reaction (OER) and poor electrochemical stability in acidic environments of electrocatalysts seriously restrict the efficiency of hydrogen production from proton exchange membrane water electrolyzers (PEMWEs). In recent years, developing corrosion-resistant and redox-active doped TiO2 with heterogeneous atoms has become an effective strategy to address this challenge. However, most of the reported studies only explore single-element doped TiO2-supported catalysts, and there are few reports comparing the doping effects of various elements at the experimental level, which is crucial for screening high-performance OER electrocatalysts. In this work, seven different metal elements M (M = V, Mn, Fe, Ni, Cu, Nb, W) are selected for doping anatase TiO2 with the same molar ratio (M/Ti) and combined with IrO2 nanoparticles to form M-doped TiO2-supported IrO2 (M–TiO2@IrO2) electrocatalysts. Electrochemical OER activity and stability results indicate that W–TiO2@IrO2 exhibits the best performance among all these catalysts in terms of comprehensively regulating the conductivity of TiO2 and the activity and stability of IrOx within the range of experimental design in this work, which originates from the appropriate energy band structure obtained through W doping, optimizing the intrinsic conductivity of the support and interfacial electronic structure between the metal oxide and support. [ABSTRACT FROM AUTHOR]

The aim of the experiment was to study the effect of curcumin on the lipid metabolism of grass goldfish and find out the appropriate amount of curcumin. 360 grass goldfish with an initial weight of (40.12±1.23) g and initial body length of (10.34±0.08) cm were selected. They were randomly divided into six groups, with three replicates in each group, and each replicate consisting of 20 individuals. Different concentrations of curcumin (0, 40, 80, 160, 320, and 640 μmol/L) were injected, and the fish were cultured for 14 days. After 7 and 14 days of curcumin injection, the concentrations of serum TC and TG in the 160-640 μmol/L curcumin group were significantly lower than those in the control group ( P<0.05). The activities of AST and ALT in the hepatopancreas of grass goldfish in the 320 μmol/L curcumin group and 640 μmol/L curcumin group were significantly lower than those in the control group ( P<0.05). The activities of CAT and T-SOD in the 320 μmol/L curcumin group were significantly higher than those in the control group ( P<0.05). The study indicates that curcumin injection can reduce the concentrations of serum TC and TG to a certain extent, and has a certain repair effect on the hepatopancreas of grass goldfish, and can improve the antioxidant capacity of the hepatopancreas. [ABSTRACT FROM AUTHOR]

In previous taxonomic studies, identification of Atlanticus species was mainly based on male morphological features, such as cercus, tenth abdominal tergum and subgenital plate. In this study, we systematically revise eight Atlanticus species (61 individuals) in East China. We sequence COI genes of all samples for identification, and compare morphologies and male calling songs. The classification based on male cerci, calling songs, and COI genes is consistent. In contrast, the morphologies of male tenth abdominal tergum and subgenital plate varied among species. In addition, we regard A. jiangyei Liu, Wang & Cheng, 2016 as a junior synonym of A. pieli Tinkham, 1941, and A. helleri Liu, Wang & Cheng, 2016 as a junior synonym of A. kiangsu Ramme, 1939. [ABSTRACT FROM AUTHOR]

Organoids are established through in vitro 3D culture, and they can mimic the structure and physiological functions of organs or tissues in vivo. Organoids have attracted much attention in recent years. They can provide a reliable technology platform for cancer research and treatment and are a valuable preclinical model for academic research and personalized medicine. A number of studies have confirmed that organoids have great application prospects in new drug development, drug screening, tumour mechanism research, and precision medicine. In this review, we mainly focus on recent advances in the application of organoids in cancer research. We also discussed the opportunities and challenges facing organoids, hoping to indicate directions for the development of organoids in the future. [ABSTRACT FROM AUTHOR]

In this paper, we study the processes of e+e− annihilation into two body final states, either two pseudoscalar mesons or one meson with a photon. The hadronic vacuum polarization form factors are calculated within the framework of resonance chiral theory in the energy region of E ≲ 2 GeV, with final state interactions taken into account. A joint analysis on the processes of e+e−→ π+π−, K+K−, K L 0 K S 0 , π0γ, and ηγ has been performed, and the latest experimental data are included. Based on the vacuum polarization form factors of these processes, we estimate their contributions to the lowest order of anomalous magnetic moment of the muon, (g – 2)μ. Combined with other contributions from hadronic vacuum polarization and other interactions from the standard model, the discrepancy between theoretical prediction and experimental measurement is ∆aμ = (24.1 ± 5.4) × 10−10, i.e., 4.5σ. [ABSTRACT FROM AUTHOR]

Background: Vesicle trafficking is a highly important process in numerous human diseases, especially in the central nervous system dysfunctions. However, as a key component of vesicle trafficking‐related genes (VRGs), Cornichon family AMPA receptor auxiliary protein 4 (CNIH4) has not been systematically elucidated in glioma so far. Methods: Differentially expressed VRGs were selected using molecular signatures database (MSigDB), The Cancer Genome Atlas (TCGA), and Genotype‐Tissue Expression (GTEx) mRNA expression profiles. Further exploration of CNIH4 was determined using LASSO‐Cox regression algorithms. Then Kaplan–Meier (K‐M) plotter, receiver operating characteristic (ROC) curves, and multivariate Cox regression analyses were utilized to assess the independent significance of CNIH4 in the CGGA validation cohort. Functional exploration was performed with Gene Set Enrichment Analysis (GSEA) and then verified using a series of functional experiments in glioma cells. Finally, the consensus clustering algorithm was applied to identify clusters in glioma samples. After that, differences in prognosis, the tumor immune microenvironment (TIME), and therapy response were evaluated between clusters. Results: CNIH4 was shown to be overexpressed in malignant glioma variants and was frequently observed in GCSs and TMZ‐resistant cell lines. Higher CNIH4 levels were significantly related to poor outcomes and positively correlated with adverse clinicopathological characteristics. Survival analyses revealed CNIH4 as an independent risk factor that outperformed traditional measures. Enrichment analysis indicated that overactive CNIH4 significantly gathered in stem cell processes. Furthermore, functional assays of silencing CNIH4 expression suppressed stem cell‐like properties in vitro and inhibited tumorigenicity in vivo. Finally, the CNIH4‐enriched subgroup negatively modulated immunotherapeutic response and reflected lower chemotherapy sensitivity for glioma patients. Conclusion: Our study identified CNIH4 as a potential VRG that regulates tumor stemness, microenvironment immunity, and chemotherapy sensitivity. It may serve as a novel prognostic factor and a promising target against glioma therapy. [ABSTRACT FROM AUTHOR]

The three-dimensional (3D) structure of chromosomes is of great significance to ensure that the genome performs various functions (e.g., gene expression) correctly and replicates and separates correctly in mitosis. Since the emergence of Hi-C in 2009, a new experimental technique in molecular biology, researchers have been paying more and more attention to the reconstruction of chromosome 3D structure. To reconstruct the 3D structure of chromosomes based on Hi-C experimental data, many algorithms have been proposed, among which ShRec3D is one of the most outstanding. In this article, an iterative ShRec3D algorithm is presented to greatly improve the native ShRec3D algorithm. Experimental results show that our algorithm can significantly promote the performance of ShRec3D, and this improvement is applicable to almost all data noise range and signal coverage range, so it is universal. [ABSTRACT FROM AUTHOR]

In this study, the Ba 3 P 2 O 8 and Mg 2 B 2 O 5 were fabricated by the solid-state reaction method separately, and the (1-x)Ba 3 P 2 O 8 -xMg 2 B 2 O 5 (x = 0.2–0.4) low-temperature co-fired ceramic (LTCC) materials were obtained in the sintering temperature range of 880–960 °C. The phase compositions, microstructures, elemental compositions, and microwave dielectric properties of the (1-x)Ba 3 P 2 O 8 -xMg 2 B 2 O 5 composite ceramics were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), and TE 01δ mode dielectric resonator method, respectively. The results revealed that the Mg 2 B 2 O 5 phase and Ba 3 P 2 O 8 phase could coexist well in the (1-x)Ba 3 P 2 O 8 -xMg 2 B 2 O 5 composite ceramics without formation of any new phases. The abnormal grain growth of Ba 3 P 2 O 8 grains was inhibited by the addition of Mg 2 B 2 O 5. In addition, through composition of Ba 3 P 2 O 8 and Mg 2 B 2 O 5 , the temperature coefficient of resonant frequency (τ f) and quality factor (Q×f) were effectively optimized, and the sintering temperature was reduced to 880–960 °C. The optimal performance of 0.8Ba 3 P 2 O 8 -0.2Mg 2 B 2 O 5 composite ceramic was achieved at a sintering temperature of 920 °C, τ f = −1.9 ppm/°C, Q×f = 61,250 GHz, and a low permittivity ε r = 10.7. The chemical compatibility test demonstrated that the composite ceramic could coexist well with silver, which indicated that the 0.8Ba 3 P 2 O 8 -0.2Mg 2 B 2 O 5 composite ceramic is a candidate LTCC material with wide application prospects. [ABSTRACT FROM AUTHOR]

Background: The triglyceride glucose-body mass index (TyG-BMI index) has been considered a reliable surrogate measure of insulin resistance; however, its ability to predict the incidence of cardiovascular disease in individuals with coronary artery disease (CAD) remains uncertain. The aim of this study was to demonstrate the correlation between the TyG-BMI index and cardiovascular incidence. Methods: A total of 2533 consecutive participants who underwent percutaneous coronary intervention (PCI) and drug-eluting stent (DES) implantation were included. Data from 1438 patients was analyzed in the study. The endpoint was defined as a composite of acute myocardial infarction, repeat revascularization, stroke, and all-cause mortality (major adverse cardiac and cerebrovascular events, MACCEs) at 34-month follow-up. The formula for calculating the TyG-BMI index is ln [fasting triglyceride (mg/dL) × fasting blood glucose (mg/dL)/2] × BMI. Results: Among the 1438 participants, 195 incident patient cases of MACCEs were ascertained. The incidence of MACCEs showed no statistically significant differences in the TyG-BMI index tertiles in the overall population. Further exploratory subgroup analysis and multivariable logistic regression analysis revealed a linear relationship between the TyG-BMI index (per 1 SD increased) and MACCEs in the elderly patients (OR = 1.22, 95% CI 1.011–1.467, p = 0.038) and in the female patients (OR = 1.33, 95% CI 1.004–1.764, p = 0.047). The addition of the TyG-BMI index to traditional risk factor models in elderly and female patients did not improve risk prediction for MACCEs. Conclusion: A higher TyG-BMI index was proportionally related to an increased incidence of MACCEs in the elderly or female patients. However, the inclusion of the TyG-BMI index did not provide better predictive performance for MACCEs in the elderly, specifically in female patients. [ABSTRACT FROM AUTHOR]

The purpose of this research is to examine the effects of the economic complexity index and its square, investments in the energy sector, green technological innovation, and the growth of the industrial structure in 32 provinces in China on carbon dioxide emissions from 2005 to 2019. Modern methods that consider cross-sectional dependency, unit root test, co-integration test, IFE estimation, and one- and two-step generalized method of moments (GMM) models were used in the econometric analysis. The results showed that the economic complexity index is to blame for the worsening trends in China's carbon dioxide emissions. In contrast, we find that the economic complexity index square, investments in renewable energy, green technical innovation, and industrial structure all help to reduce carbon dioxide emissions, which is helpful for China's carbon-abatement goals. Carbon emissions are negatively affected by renewable energy's limited effect on green technology innovation and industrial structure. Based on these findings, a number of policy suggestions are offered. • This study uses the innovative determinants of sustainable development. • This study uses the IFE and series of GMM Estimators. • Industrial sector, GTI and REI rises the level of sustainable development. • There exists an inverted U-shaped EKC-hypothesis. • Moderate role of REI significantly improves the level of environment. [ABSTRACT FROM AUTHOR]

To constrain the behavior of K isotopes during granitic magmatic differentiation, we present high-precision K isotope data for bulk granitoids and their K-bearing minerals from Dabie and Himalayan orogens in China. Plagioclase displays extremely large K isotopic variation, with δ41K ranging from −0.56 to 1.91‰. Other minerals also have heterogeneous K isotopic compositions, with δ41K varying from −0.56 to −0.24‰ in hornblende, from −0.72 to −0.39‰ in biotite, from −0.79 to −0.47‰ in K-feldspar, and from −0.74 to −0.61‰ in muscovite. The general trend of 41K enrichment follows the order of plagioclase ≫ hornblende > biotite ≈ K-feldspar ≥ muscovite, which can be attributed to the difference in K O bond strengths. Both δ41K of plagioclase and K isotope fractionation factors between plagioclase and other minerals are negatively correlated with K concentration in plagioclase, suggesting a compositional control on isotope fractionations. Inter-mineral K isotope fractionations among other minerals are roughly temperature-dependent. Potassium isotopic compositions of whole rocks display measurable variations (δ41K = –0.69 to −0.28‰), which are correlated with proxies for plagioclase fractionation (e.g., Sr and Rb/Sr). The correlation indicates that fractional crystallization may account for the whole-rock K isotopic variations observed in high-silica igneous rocks, which is supported by modeling of fractional crystallization using the apparent isotope fractionation factors determined in this work. Our study demonstrates the existence of large K isotope fractionation during granitic magmatism, making K isotopes a potential tool for studying differentiation of felsic magmas. [ABSTRACT FROM AUTHOR]

Acute pancreatitis (AP) is an acute inflammatory disease of the exocrine pancreas. The pathogenesis of AP is still unclear, and there is currently no specific treatment. A variety of immune cells infiltrate in AP, which may play an important role in the progression of the disease. In this study, for the first time, scRNA-Seq and Bulk RNA-Seq data were used to show the characteristics of immune cell infiltration in AP, and to explore the specific molecular markers of different cell types. The present study also investigated cell-to-cell communication networks using the CellChat package, and AP-specific gene signatures (Clic1, Sat1, Serpina3n, Atf3, Lcn2, Osmr, Ccl9, Hspb1, Anxa2, Krt8, Cd44, Cd9, Hsp90aa1, Tmsb10, Hmox1, Fxyd5, Plin2, Pnp) were identified through integrative analysis of multiple sequencing datasets. We also defined disease-specific associated genes in different cell types, revealing dynamic changes through cell trajectory and pseudo-time analysis using the Monocle2 package. The results showed that macrophages were significantly increased in acute pancreatitis, and the number of interactions and interaction weight/strength of the macrophages in AP were significantly higher than those in the controls. The activities of various signaling pathways were abnormally regulated such as apoptosis, oxidative stress, lysosome, autophagy, ferroptosis, and inflammatory responses signaling pathways. In conclusion, this study comprehensively depicted the immune microenvironment of AP, explored the interaction network between different cell types, and defined AP-specific gene signatures, providing many new directions for basic research in AP. [ABSTRACT FROM AUTHOR]

The N(6)-methyladenosine (m6A) modification is the most pervasive modification of human RNAs. In recent years, an increasing number of studies have suggested that m6A likely plays important roles in cancers. Many studies have demonstrated that m6A is involved in the biological functions of cancer cells, such as proliferation, invasion, metastasis, and drug resistance. In addition, m6A is closely related to the prognosis of cancer patients. In this review, we highlight recent advances in understanding the function of m6A in various cancers. We emphasize the importance of m6A to cancer progression and look forward to describe future research directions. [ABSTRACT FROM AUTHOR]

Dielectric capacitors are ideal for high power pulse system due to their high‐power density. However, the traditional dielectric capacitor cannot achieve large capacitance density and combine with the high breakdown voltage. Through this research, the internal structure of photosensitive glass can be transformed into multilayer interdigital electrodes structure through photolithography and laser induced processes. It is realized through the transition from the 2D structure to the 3D interdigital electrodes dielectric capacitor. In this case, the specific surface area electrode structure presents exponential increase and dielectric layers thickness decrease, which provide a large capacitance density. The new 3D capacitors, via reducing the roughness of the electrode surface, a uniform porous inner wall improves the breakdown strength (8.15 MV cm−1, which is 2 times to photolithographic). As a result, these highly‐density regular electrodes array effectively improve the capacitance density to 48.5 nF cm−2, which is 422 times larger than that of planar structure. Moreover, the new 3D capacitors fabricated by laser‐induce exhibit smoother inner wall surface and more rounded shape of electrode holes, achieving very large energy storage density of ≈3.4 Wh kg−1 (14.688 J cm−3) and power density of ≈6.48 × 1011 W kg−1. [ABSTRACT FROM AUTHOR]

Knowledge of the behavior of magnesium (Mg) isotopes during magmatic differentiation is a prerequisite for applying Mg isotopes as a tracer of crustal recycling and mantle heterogeneity. Crystal fractionation of mafic silicate minerals leads to limited Mg isotope fractionation; hence, Mg isotopic variations in basalts largely result from contributions of subducted crustal materials into their mantle sources. However, recent studies have revealed that the segregation of iron oxides, such as chromite during early-stage basaltic differentiation and titanomagnetite and ilmenite during late-stage differentiation, can potentially modify Mg isotopic compositions of mantle-derived lavas. Titanomagnetite is much more commonly observed in terrestrial basaltic lavas than chromite and ilmenite, and can also form during early-stage basaltic differentiation. To constrain the effects of titanomagnetite crystallization on Mg isotopic systematics of basaltic magma, we report Mg isotopic data for a suite of well-characterized alkaline basaltic lavas (MgO wt% = 4.99 to 6.52) from Gerba Guracha, western Ethiopian Plateau, which have undergone extensive titanomagnetite fractionation. Their δ26Mg values range from −0.29‰ to −0.17‰ and do not correlate with indicators of titanomagnetite fractionation such as TiO 2 and V. These observations suggest that the segregation of titanomagnetite produced limited Mg isotope fractionation, possibly because of its composition-dependent, highly variable Δ26Mg Ti-Mgt−melt (Δ26Mg Ti-Mgt−melt = δ26Mg Ti-Mgt − δ26Mg melt) values. Considering that most iron oxides occur as complex solid solutions that are controlled by the oxygen fugacity of magmas, the effects of oxide segregation on Mg isotopic systematics of basalts require further evaluation. • Alkaline basaltic lavas from Gerba Guracha display limited Mg isotopic variations. • The δ26Mg values do not correlate with indicators of titanomagnetite fractionation. • Titanomagnetite fractionation has produced limited Mg isotope fractionation. [ABSTRACT FROM AUTHOR]

1. The Ir a Hf b Al c alloy thin films were deposited by Direct Current Magnetron Sputtering (DC-MS). 2. We for the first time prepared Ir a Hf b Al c alloy thin films with a preferred (111) orientation substitution solid solution, which have the advantages of mechanical properties and oxidation resistance. 3. The mechanical properties of the Ir a Hf b Al c alloy films were significantly improved over the previous ones, with maximum hardness (H) and modulus of elasticity (E) exceeding 20 GPa and 330 GPa, respectively. 4. The catalytic activity of Ir in Ir a Hf b Al c films is effectively reduced. The volatilization temperature of the films is increased and the overall oxidation resistance is substantially improved. [Display omitted] • The Ir a Hf b Al c alloy thin films with a preferred (111) orientation substitution solid solution were first prepared by us for the first time. It has the advantages of mechanical properties and oxidation resistance. • The mechanical properties of the Ir a Hf b Al c alloy films were significantly improved over the previous ones. The minimum surface roughness (Ra) value of the IraHfbAlc alloy films was 0.7 nm, while the maximum hardness (H) and elastic modulus (E) exceeded 20 GPa and 330 GPa, respectively. • The oxidized volatility of the Ir in the films was only 0.11 μm/h at 1300 °C (lower than most of the previously reported values, such as 0.5 μm/h). The oxidation rate was slowed down by 50 % compared to the previous one, which greatly improved the lifetime of the film. • Moreover, the modified Ir a Hf b Al c alloy thin films reduce the catalytic activity of Ir metal, reduces the thermal effect and increases the volatilization temperature. • Detailed analysis of microscopic phenomena reveals the presence of crystal-like order (CLO) in thin films, solving the mystery of improved oxidation resistance and mechanical properties. Improving oxidation resistance has long been a challenge for hot end components in high temperature environments. We have fabricated a series of Ir a Hf b Al c (at. %) alloy thin films by multi-targeted direct current magnetron sputtering (DC-MS) and have thoroughly investigated the microscopic mechanism of the films. More importantly, we for the first time prepared Ir a Hf b Al c alloy thin films with a preferred (111) orientation substitution solid solution, which exhibits excellent mechanical properties and oxidation resistance. The minimum surface roughness (R a) value of the Ir a Hf b Al c alloy films was 0.7 nm, while the maximum hardness (H) and elastic modulus (E) exceeded 20 GPa and 330 GPa, respectively. The oxidized volatility of the Ir in the films was only 0.11 μm/h at 1300 °C (lower than most previously reported values, such as 0.5 μm/h), which greatly improved the lifetime of the film. Confirmation that lattice distortion induces the refinement of crystal-like order (CLO) in thin films, and solves the mystery of enhanced oxidation resistance. The findings provide important insights into the design of Ir-containing alloy coatings and offer new ideas in the field of high-temperature protection. [ABSTRACT FROM AUTHOR]

Overhead ground wires installed on transmission lines have been proved to be effective to protect conductors from direct lightning strokes, but ground wire breakouts due to icing are frequently reported. In order to prevent electric failure accidents caused by ground wire breakouts under icing conditions, unshielded transmission lines equipped with metal oxide arresters (MOAs) whole line have been proposed in high mountainous areas. Compared with ordinary transmission lines, lightning stroke risk of unshielded lines is much higher. In order to improve the lightning performance of unshielded lines, it is necessary to obtain the essential lightning energy absorption ability of the MOAs installed on unshielded lines. In this article, simulation model of unshielded 220 kV transmission lines equipped with MOAs is built, the influences of lightning parameters, striking occurrence point and grounding resistance on the absorbed energy of MOAs are analyzed. Based on Monte Carlo method, lightning trip-out rate of unshielded transmission lines are calculated, and suggested energy absorption ability of MOAs is proposed, which can give references for the improvement of power supply reliability of transmission lines. [ABSTRACT FROM AUTHOR]

Potassium isotopes may provide a novel approach for fingerprinting recycled sediments in the mantle due to the significant differences in K abundance and isotopic ratio between subducting sediment and the mantle. However, the behavior of K isotopes in sediments during subduction zone metamorphism is still unknown. Here we investigate K isotopic composition of a set of well-characterized high- to ultrahigh-pressure metasediments from the Schistes Lustrés nappe (western Alps), which represents marine sediments subducted down to ~90 km depth in a cold subduction zone, and their protoliths from the Lavagna nappe (Apennines, Italy). The metasediments display δ41KSRM 3141a values from –0.76‰ to –0.48‰, which are on average lower than the mantle value (–0.43‰) but similar to those of non-metamorphic equivalents (–0.79‰ to –0.49‰). No systemic variation of δ41K with metamorphic grade is observed, suggesting negligible K isotope fractionation in these sediments during prograde metamorphism. This is in accord with the limited loss of K during the entire metamorphic history as evidenced by the constancy of K/Rb and K/Cs ratios between metamorphic and non-metamorphic sediments and the absence of correlations of δ41K with K/Rb and K/Cs. The heterogeneous δ41K values of metasediments are most likely inherited from their protoliths, which experienced different degrees of chemical weathering depending on their provenances. Our results demonstrate that the variable and light K isotopic signatures in subducting sediments could be preserved to depths of at least 90 km along a cold geotherm gradient, indicating that the introduction of sediments into the mantle could produce K isotope heterogeneity in the source regions of mantle-derived lavas. [ABSTRACT FROM AUTHOR]

[Display omitted] • GO/PANI nanocomplex electrode with high biocompatibility was fabricated. • GO/PANI@CP electrode showed 54 times of power density compared to blank CP. • Bacteria on electrode surface showed fast electron release and uptake. • Efficient bio-denitrification in cathode was developed via GO/PANI@CP electrode. Bidirectional electron transfer is about that exoelectrogens produce bioelectricity via extracellular electron transfer at anode and drive cytoplasmic biochemical reactions via extracellular electron uptake at cathode. The key factor to determine above bioelectrochemical performances is the electron transfer efficiency under biocompatible abiotic/biotic interface. Here, a graphene/polyaniline (GO/PANI) nanocomposite electrode specially interfacing exoelectrogens (Shewanella loihica) and augmenting bidirectional electron transfer was conducted by in-situ electrochemical modification on carbon paper (CP). Impressively, the GO/PANI@CP electrode tremendously improved the performance of exoelectrogens at anode for wastewater treatment and bioelectricity generation (about 54 folds increase of power density compared to blank CP electrode). The bacteria on electrode surface not only showed fast electron release but also exhibited high electricity density of extracellular electron uptake through the proposed direct electron transfer pathway. Thus, the cathode applications of microbial electrosynthesis and bio-denitrification were developed via GO/PANI@CP electrode, which assisted the close contact between microbial outer-membrane cytochromes and nanocomposite electrode for efficient nitrate removal (0.333 mM/h). Overall, nanocomposite modified electrode with biocompatible interfaces has great potential to enhance bioelectrochemical reactions with exoelectrogens. [ABSTRACT FROM AUTHOR]

[Display omitted] • A biohydrogel electrode containing nanosheets and Shewanella was farbicated. • Biohydrogel was modified into photoanode with thylakoid membrane. • Photoanode produced maximum photocurrent 126 μA/cm3 under visible light. • 5.4 mM butyrate was yield from CO 2 bio-reduction in photoelectrochemical cell. Bio-photoelectrochemical cell (BPEC) is an emerging technology that can convert the solar energy into electricity or chemicals. However, traditional BPEC depending on abiotic electrodes is challenging for microbial/enzymatic catalysis because of the inefficient electron exchange. Here, electroactive bacteria (Shewanella loihica PV-4) were used to reduce graphene oxide (rGO) nanosheets and produce co-assembled rGO/ Shewanella biohydrogel as a basic electrode. By adsorbing chlorophyll contained thylakoid membrane, this biohydrogel was fabricated as a photoanode that delivered maximum photocurrent 126 μA/cm3 under visible light. Impressively, the biohydrogel could be served as a cathode in BPEC by forming coculture system with genetically edited Clostridium ljungdahlii. Under illumination, the BPEC with above photoanode and cathode yielded ∼ 5.4 mM butyrate from CO 2 reduction, 169 % increase compared to dark process. This work provided a new strategy (nanotechnology combined with synthetic biology) to achieve efficient bioelectricity and valuable chemical production in PBEC. [ABSTRACT FROM AUTHOR]

Self-healable hydrogels have attracted significant interests in the fields of environmental protection, oil plugging and electronic sensors, etc. Benefiting from the synergistic contribution of hydrogen bonding and ligand chelation, in this work, we prepared a series of self-healable hydrogels via a simple and inexpensive approach, which overcame the limitations of the intrinsic nature of dynamic covalent bonds and non-covalent interactions under harsh conditions. Systematic study of the effect of temperature, salt concentration and particle size on the physicochemical performance of the re-crosslinking progress revealed that re-crosslinked gels using particles of 0.20–0.28 mm (in a solution with salt concentration of 10%) at 130 °C presented an elastic modulus of 62 Pa at a frequency of 10 Hz and remained elastic after 45 days of aging (elastic modulus: 18,170 Pa). Of particular interest, gel particles with a particle size of 0.125–0.28 mm can be reassembled at temperatures up to 150 °C or salt concentrations up to 20%, which is superior to a plethora of previous reports (self-healing temperature usually less than 130 °C, salt concentration <10%). Employment of the green inexpensive sodium D-gluconate instead of partial acrylamide makes the gel product a promising candidate material for oil plugging, targeting fractured reservoirs for consistent control. [Display omitted] • Self-healable hydrogels were fabricated in a simple and inexpensive method. • Hydrogels were capable of re-crosslinking at harsh conditions. • Chelation of metal ions and hydrogen bonds contributed to the re-crosslinking process. • This re-crosslinkable hydrogel is a promising candidate for oil plugging. [ABSTRACT FROM AUTHOR]

Protein compartments are distinct structures assembled in living cells via self-assembly or phase separation of specific proteins. Significant efforts have been made to discover their molecular structures and formation mechanisms, as well as their fundamental roles in spatiotemporal control of cellular metabolism. Here, we review the design and construction of synthetic protein compartments for spatial organization of target metabolic pathways toward increased efficiency and specificity. In particular, we highlight the compartmentalization strategies and recent examples to speed up desirable metabolic reactions, to reduce the accumulation of toxic metabolic intermediates, and to switch competing metabolic pathways. We also identify the most important challenges that need to be addressed for exploitation of these designer compartments as a versatile toolkit in metabolic reprogramming. • Compartment formation driven by protein self-assembly or phase transition. • Pathway enzymes can be directed into compartments for metabolic engineering. • Membraneless compartments enable dynamic control of metabolic pathways. • Synthetic protein compartments enable spatial control of cellular metabolism. [ABSTRACT FROM AUTHOR]

• Magnesium isotopic compositions are reported of magnetite in layered mafic intrusions for the first time. • Large Mg isotopic variation in magnetite is primarily governed by subsolidus processes. • Magnesium isotopic compositions of magnetite are related to mineral proportions in the cumulates. • Primitive Mg isotopic signature of coexisting Fe–Ti oxides indicates early crystallization in origin. To constrain the mechanisms governing the extremely large variations of Mg and Fe isotopes in magmatic Fe–Ti oxides in layered mafic intrusions, we investigate Mg isotopic compositions of magnetite, coupled with its chemical data and whole-rock major element and Sr-Nd isotope compositions from the Baima layered mafic intrusion in the Emeishan large igneous province, SW China. The Baima intrusion is mainly composed of magnetite-wehrlite and magnetite-troctolite (i.e., oxide-rich rocks) in the Lower Zone, and troctolite and gabbro (i.e., oxide-barren rocks) in the Middle and Upper Zones. Magnetite separates display large Mg isotopic variation, with δ26Mg ranging from −0.17 ± 0.06 to +0.58 ± 0.04‰ in the oxide-rich rocks and from −0.18 ± 0.06 to +0.98 ± 0.04‰ in the oxide-barren ones. The lack of correlation of δ26Mg with trace elements in magnetite and whole-rock Sr-Nd isotopic compositions indicates that the large Mg isotopic variation in magnetite was not produced by fractional crystallization, magma mixing, crustal contamination, and/or trapped liquid shift. Instead, equilibrium isotope fractionation induced by Mg–Fe re-equilibration between magnetite and ilmenite at different subsolidus temperatures controlled the Mg isotopic variation in the oxide-rich rocks; and kinetic isotope fractionation driven by Mg–Fe inter-diffusion between magnetite and olivine and/or clinopyroxene dominated the oxide-barren rocks. Both processes were primarily controlled by the assemblage and modal abundance of coexisting minerals to which magnetite adjoins. Overall, fractional crystallization and subsequent subsolidus diffusion played crucial roles in the genesis of the Fe–Ti oxides in the Baima intrusion. Our results also reveal widespread isotope disequilibrium between coexisting minerals in mafic magma chambers and suggest that Mg isotope geochemistry has a great potential to characterize the formation of Fe–Ti oxides in layered mafic intrusions. [ABSTRACT FROM AUTHOR]

Cratonic lamproites bear extreme Sr−Nd−Pb isotopic compositions widely known as enriched mantle I (EMI), yet the origin of the EMI reservoir remains controversial. Here, we explore this issue by examining Mg−Sr−Nd−Pb isotopic compositions of lamproites from Leucite Hills, Wyoming, USA. The δ26Mg values vary from the range of the normal mantle to lower values (− 0.43 to − 0.18 ‰), correlating with indices of the degree of carbonate metasomatism, an observation that can be best explained through mantle metasomatism by subducted carbonate-bearing sediments. With increasing extent of carbonate metasomatism, these samples display less extreme EMI Sr−Nd−Pb isotopic signatures, arguing for at least two metasomatic events that occurred in their mantle sources. The early metasomatic event associated with subducted continent-derived siliciclastic sediments led to the formation of the EMI Sr−Nd−Pb isotopic signatures while the recent carbonate metasomatism produced the light Mg isotopic signature but diluted the EMI Sr−Nd−Pb isotopic signatures. Our study indicates that a combination of Mg and Sr−Nd−Pb isotopes could be an effective tool in deciphering multiple-stage metasomatic events in mantle sources and places new constraints on the generation of enriched mantle reservoirs. [ABSTRACT FROM AUTHOR]

We studied the magnetic effects on the chiral transition and the melting properties of vector and axial-vector mesons in the improved soft-wall AdS/QCD model under a charged magnetic background, which is solved perturbatively from an Einstein–Maxwell system with a negative cosmological constant. The phase diagrams for both chiral transition and meson melting have been obtained. We show that the inverse magnetic catalysis emerged naturally in the improved soft-wall model. We also find that the magnetic field can induce meson melting, at least for the vector and axial-vector mesons, in our holographic setup. [ABSTRACT FROM AUTHOR]

Stable potassium (K) isotopes are emerging as tracers of terrestrial recycling and planetary processes. These applications require well‐defined K isotopic compositions for the mantle and the bulk silicate Earth (BSE). Both values are determined primarily by basalts formed via partial melting of the mantle. Basaltic melts experience igneous differentiation before reaching the surface, which may alter their isotopic compositions compared to their mantle sources. This study investigates K isotope fractionation during the differentiation and solidification of the Kilauea Iki lava lake, Hawaii, for which crystallization and thermal histories are well documented. High‐precision K isotopic ratios (δ41K) are measured in 13 Kilauea Iki samples that cover its complete differentiation history, ranging from olivine‐rich, high‐MgO cumulates to increasingly differentiated, MgO‐depleted samples. The limited δ41K range of −0.42 to −0.37‰ in all but one sample reveals no analytically resolvable fractionation across diverse bulk compositions, even though their bulk MgO contents varied from 26.9 to 2.37 wt.%. The lack of K isotopic fractionation is consistent with an absence of K‐rich minerals in the crystallizing assemblage, where only plagioclase can accommodate a small amount of K. A highly differentiated vein displays the lowest δ41K of −0.47‰ among the Kilauea Iki suite, which is consistent with our modeling calculations that suggest measurable K isotope fractionation at more advanced magmatic differentiation stages. Combining our new results with literature data, we propose an average δ41K of −0.42 ± 0.08‰ (2SD) for the pristine mantle and of −0.42 ± 0.07‰ (2SD) for the BSE. Key Points: Limited potassium (K) isotope fractionation during basaltic differentiationMeasurable K isotope fractionation occurs at advanced stages of differentiationThe K isotopic composition of the mantle can be constrained by oceanic basalts [ABSTRACT FROM AUTHOR]

Arc magmas derived from mantle melting often have trace element and isotopic signatures that indicate crustal contributions. The origin and extent of crustal contributions are critical constraints for quantifying crust-mantle recycling at subduction zones; however, it is difficult to distinguish between inputs from the downgoing oceanic slabs and that of the over-riding arc crust. Here we present a novel study using stable potassium (K) isotopes to fingerprint the long-debated crustal signatures in lavas from Martinique Island, Lesser Antilles arc. We find δ41K of Martinique lavas varies from −0.66 to 0.01‰ and correlates with chemical parameters and radiogenic isotope ratios. These correlations cannot be produced by assimilation of arc crust during magma ascent. Rather, they reflect mantle sources that have been modified by the input of subducted sediments. Most lavas display a strong negative correlation between δ41K and radiogenic isotopic compositions, from typical mantle values of −0.37‰ to much lower values of −0.66‰, suggesting the addition of <1% to 5% subducted sediments to their mantle sources. Notable divergence in this correlation occurs for three samples with variably high δ41K (−0.28 to 0.01‰), which is likely caused by the addition of isotopically heavy K-bearing fluids derived from slab dehydration. Our study indicates that a substantial fraction of large ion lithophile elements, including K in arc magmas and thus nascent crust, is inherited from subducted crust; K isotopes are useful tracers of this cycling process. [ABSTRACT FROM AUTHOR]

Background: The research on plant salt tolerance has mainly focused on Na+, but Cl− has been relatively neglected. Previous studies have found that the xerophyte Pugionium cornutum, an important forage grass in the arid and semi‐arid regions of northwestern China, could synergistically accumulate high quintiles of Na+ and Cl− in its shoots under NaCl treatments. However, the separate effects of these ions on the adaptation of P. cornutum to saline conditions have not been investigated. Aims: In this study, the response of P. cornutum to Na+ and Cl− was analyzed. Methods: Four‐week‐old seedlings were treated with additional 50 mM NaCl, Na+‐specific solution containing 50 mM Na+ with a mix of NO3-, H2PO4-, and SO42- as counter anions, and Cl−‐specific solution containing 50 mM Cl− with a mix of K+, Ca2+, and Mg2+ as counter cations. Results: Compared with the normal growth condition irrigated with Hoagland solution, the Na+‐specific solution severely impaired the growth and photosynthesis of P. cornutum due to the high accumulation of Na+ in shoots and the deterioration of tissue K+ homeostasis; while the Cl−‐specific solution significantly increased shoot fresh and dry biomass. The Cl−‐specific solution could also increase the turgor pressure in leaves for enhancing osmotic adjustment, which should be mainly attributed to the large accumulation of Cl−, since the concentrations of other ions, including K+, Mg2+, Ca2+, H2PO4-, and SO42-, in tissues under Cl−‐specific treatment were maintained at the same levels as those observed under the normal condition. Conclusions: P. cornutum displays an excellent tolerance to moderate Cl− but not to Na+, and the large accumulation of Cl− should play a positive role in stimulating the growth of P. cornutum under salt stress. [ABSTRACT FROM AUTHOR]

Lignocellulosic nanofibril (LCNF) is indispensable in numerous potential applications because of its unsurpassed quintessential characteristics. While it still remains a challenge to assemble LCNF in a facile and environmental economy-first manner. In this work, a simple and green one-step synthetic approach was reported to prepare a series of LCNF-containing versatile hydrogels using deep eutectic solvent (DES). In particular, the LCNF5% hydrogel (namely LCNF5%-gel) in this work perfectly integrated superior stretchability (∼643 %), and displayed a dramatically improved anti-swelling ability (25 %) compared to the control sample (neat DES hydrogel, 2252 %). Simultaneously, the LCNF5% hydrogel presented underwater adhesiveness and outstanding long-term low-temperature resistance (stable at −25 °C for a month). This novel multifunctional hydrogel, prepared by a facile and eco-friendly strategy, is potentially useful in wet adhesion or underwater applications. • Lignocellulose nanofibril was used to prepare multifunctional hydrogels. • This hydrogel was prepared with a one-step approach using deep eutectic solvent. • The hydrogel presented good anti-swelling and long-term low-temperature resistance. • The product can be potentially useful in wet adhesion or underwater applications. [ABSTRACT FROM AUTHOR]

The REBa 2 Cu 3 O x (REBCO) tape, known for its exceptional mechanical properties, stands as an optimal conductor for high-field applications. Nevertheless, stress degradation attributed to the membrane and monofilament structure of REBCO tape often occurs in high-field REBCO coils. On the other hand, iron-based superconductor (IBS) tapes offer notable advantages, including multifilament structure and upper critical field above 150 T, rendering it an appealing choice for high magnetic field applications. In this context, we first propose a methodology for designing a new type of compact hybrid magnet that integrates REBCO coils with multifilament IBS coils and a water-cooled resistive magnet to generate a high magnetic field. This paper presents the preliminary design of a hybrid magnet and employs a numerical simulation model to assess the magnet's electromagnetic and mechanical configuration, the simulation results show that the stress and strain experienced by all coils is within safe limits. Furthermore, details of the fabrication and testing of the IBS-REBCO joint are also provided. We hoped that the resistance of the IBS-REBCO joint would be less than 50 nΩ, however the resistance of the joint we developed did not meet our expectations. We discuss the reasons and propose the next plan to improve the performance of the IBS-REBCO joint. [ABSTRACT FROM AUTHOR]

Avoiding the use of expensive catalysts and harsh conditions such as elevated temperatures and high pressures is a critical goal in lignin depolymerization and valorization. In this study, we present a thio-assisted electrocatalytic reductive approach using inexpensive reticulated vitreous carbon (RVC) as the working cathode to cleave the β-O-4-type linkages in keto aryl ethers. In the presence of a pre-electrolyzed disulfide (2,2′-dithiodiethanol) and a radical inhibitor (BHT) at room temperature at a current density of 2.5 mA cm−2, cathodic reduction of nonphenolic β-O-4 dimers afforded over 90% of the corresponding monomeric C–O cleavage products in only 1.5 h. Extended to DDQ-oxidized poplar lignin, this combination of electric current and disulfide, applied over 6 h, released 36 wt% of ethyl acetate soluble fragments and 26 wt% of aqueous soluble fragments, leaving only 38 wt% of insoluble residue. These findings represent a significant improvement over the current alone values (24 wt% ethyl acetate soluble; 22 wt% aqueous soluble; 54 wt% insoluble residue) and represent an important next step in our efforts to develop a mild electrochemical method for reductive lignin deconstruction. [ABSTRACT FROM AUTHOR]

The article focuses on a study which described high-precision measurements that reveal variability in oceanic plates and offers insights into the oceanic K cycle and mantle heterogeneity. Results of the study are discussed. Materials and methods used in the study are described. The direction and extent of associated franctionations are also examined.

Marine ecosystem recovery after the latest Permian mass extinction (LPME) was a protracted process during the Early Triassic (∼252–247 Ma) owing to repeated climatic and environmental perturbations. Chemical weathering can supply nutrients to the ocean and may have played an important role in the Early Triassic carbon cycle and biological recovery. However, only limited geochemical records of chemical weathering during the Early Triassic have been presented to date, and the relationship between changes in weathering intensity and the slow recovery of marine ecosystems is effectively unknown. Here, we report magnesium (Mg) isotopic compositions of the siliciclastic components from shallow-marine carbonates in two well-studied Upper Permian-Lower Triassic sections in Iran and South China to track changes in chemical weathering intensity after the LPME. Both sections display a wide range of δ26Mg values (−2.09‰ to +1.10‰ at Zal, −2.30‰ to +0.33‰ at Zuodeng). We identified two distinct stages (I and II) in each section based on δ26Mg values and major elemental ratios. Variations of δ26Mg values in Stage I (Changhsingian to mid-Dienerian) are mainly controlled by mineralogical composition that can obscure weathering signals. By contrast, δ26Mg variations in Stage II (upper Dienerian to upper Spathian) are independent of lithology and inferred to reflect control by chemical weathering intensity. The trends in chemical weathering intensity within Stage II correspond to first-order variations in climate and carbon cycling. Marine ecosystem recovery during the Early Triassic may have been linked to recurrent episodes of intense chemical weathering caused by CO 2 degassing and climate warming. This study demonstrates the potential utility of the Mg isotopic compositions of the silicate fraction in marine carbonates as a proxy for chemical weathering intensity, laying the groundwork for general applications of this method to deep-time Earth systems. [ABSTRACT FROM AUTHOR]

Magnesium (Mg) isotopes in carbonate minerals are a useful proxy for paleoclimate studies, but interpretations are often limited by an inadequate understanding of the various factors controlling Mg isotopic fractionation during carbonate formation. Previous work has studied a number of parameters including aqueous chemistry, mineralogy, temperature, and precipitation rate. However, little is known about the impact of solid/solution ratio, calcite growth mechanism, and crystal morphology on isotope fractionation. In this work, two groups of seeded chemo-stat calcite precipitation experiments were conducted at 25 °C to explore the potential impact of crystal growth and morphology on the fractionation of Mg isotopes. Group-1 experiments (G1) contained nine individual runs that were performed under identical physicochemical conditions, except for solid/solution ratio and the length of an experiment. The isotope fractionation between precipitated calcite and aqueous solution is limited, with Δ26Mg cal-sol ranging from −2.58 to −2.40‰ and an average of −2.49 ± 0.12‰ (2SD, n = 9). The Group-2 experiments (G2) contained 3 paired runs with solution Mg/Ca molar ratios of 0.5, 2.0, and 5.0, and yielded Δ26Mg cal-sol values that ranged from −2.69 to −2.36‰ with an average of −2.62 ± 0.25‰ (2SD, n = 6). The average Δ26Mg cal-sol value for both sets of experiments is −2.54 ± 0.22‰ (2SD, n = 15), and it is independent of precipitation rate, solution Mg/Ca molar ratio, solid/solution ratio, amount of overgrowth, and mol% Mg content in overgrowth. The form and texture of the calcite overgrowths in our experiments range from {104} rhombohedra with smooth crystal faces containing few macrosteps to {104} rhombohedra containing extensive evidence for 2-D nucleation on crystal faces, to more steeply sided rhombohedra {0 kl }. While significant changes in crystal morphology are related to solid/solution ratio and solution composition in the G1 and G2 experiments, respectively, there was no difference in Mg isotope systematics, suggesting that crystal morphology does not affect the Mg isotopic composition of calcite within the range of features investigated and 2-D nucleation may be less affected by calcite growth kinetics than a spiral growth mechanism. Integrating our results with previous published values, an equilibrium isotopic fractionation factor of −2.47 ± 0.09‰ (weighted average ± weighted 2SD, n = 70) between calcite and aqueous solutions is derived at room temperature. [ABSTRACT FROM AUTHOR]

Background: Chromatin 3D conformation plays important roles in regulating gene or protein functions. High-throughout chromosome conformation capture (3C)-based technologies, such as Hi-C, have been exploited to acquire the contact frequencies among genomic loci at genome-scale. Various computational tools have been proposed to recover the underlying chromatin 3D structures from in situ Hi-C contact map data. As connected residuals in a polymer, neighboring genomic loci have intrinsic mutual dependencies in building a 3D conformation. However, current methods seldom take this feature into account. Results: We present a method called ShNeigh, which combines the classical MDS technique with local dependence of neighboring loci modeled by a Gaussian formula, to infer the best 3D structure from noisy and incomplete contact frequency matrices. We validated ShNeigh by comparing it to two typical distance-based algorithms, ShRec3D and ChromSDE. The comparison results on simulated Hi-C dataset showed that, while keeping the high-speed nature of classical MDS, ShNeigh can recover the true structure better than ShRec3D and ChromSDE. Meanwhile, ShNeigh is more robust to data noise. On the publicly available human GM06990 Hi-C data, we demonstrated that the structures reconstructed by ShNeigh are more reproducible between different restriction enzymes than by ShRec3D and ChromSDE, especially at high resolutions manifested by sparse contact maps, which means ShNeigh is more robust to signal coverage. Conclusions: Our method can recover stable structures in high noise and sparse signal settings. It can also reconstruct similar structures from Hi-C data obtained using different restriction enzymes. Therefore, our method provides a new direction for enhancing the reconstruction quality of chromatin 3D structures. [ABSTRACT FROM AUTHOR]

Potassium isotopic compositions of profiles through saprolites developed on a diabase in South Carolina, U.S.A., and on a granite in Guangdong, China, allow characterization of the behavior of K isotopes during continental weathering. Saprolites from the diabase profile are heavily weathered with chemical index of alteration (CIA) values up to 95; however, their K isotopic variation is limited, with δ41K ranging from −0.475 ± 0.028‰ in the unweathered diabase to −0.407 ± 0.021‰ for the saprolites. The lack of significant K isotope fractionation mainly reflects the conservative behavior of K in the diabase weathering profile, with >50% of the original K remaining in the saprolites. By contrast, K isotopes are fractionated during granite weathering and correlate with sample depth, CIA, and kaolinite abundance, with δ41K decreasing from −0.493 ± 0.030‰ in the unweathered granites at the bottom to −0.628 ± 0.021‰ in the most weathered saprolite close to the surface. These observations suggest the preference of light K isotopes in saprolites relative to fluids, which is further supported by the overall isotopically heavy nearby stream water samples (δ41K = −0.709 ± 0.017 to −0.339 ± 0.018‰). These results demonstrate that continental weathering plays an important role in the global K isotopic budget through the formation of isotopically heterogeneous rivers and weathered regolith. Recycling of K-rich crustal materials with distinct K isotopic signatures may produce distinct mantle K isotopic end members. [ABSTRACT FROM AUTHOR]

Continental crust loses Mg by lower crustal foundering and chemical weathering to become its intermediate-silicic composition. Both processes should preferentially retain heavy Mg isotopes in the crust, yet the estimated Mg isotopic ratio for the bulk continental crust is indistinguishable from that for unmodified mantle. This can be elucidated by two notions that are not mutually exclusive: (i) the basaltic parent to the crust has Mg isotopes lighter than the mantle and has since become mantle-like as a result of Mg loss by igneous and weathering fractionation, and (ii) heavy Mg isotopes in the continental crust are constantly balanced by a hidden input of light Mg isotopes. Arc magmas are arguably building blocks of the continental crust and their Mg isotopic signature could be used to place limits on the above views. Here, we conducted a Mg isotopic study of the Makran arc, a rare continental arc in Iran within the Alpine-Himalayan orogenic belt. The measured Mg isotopic ratios for most mafic and intermediate samples are mantle-like with δ26Mg values ranging from −0.32‰ to −0.20‰. After excluding dubious samples affected by alteration, the silicic samples span a broad range of isotopic ratios with δ26Mg values ranging from −0.32‰ to +0.32‰, beyond that of unmodified mantle (δ26Mg = −0.25 ± 0.04‰). The isotopic data form a trend from mantle-like δ26Mg at relatively high MgO towards elevated δ26Mg at low MgO, requiring the isotopic variability be related to differentiation in an open system involving assimilation of high-δ26Mg crustal rocks. Our results are generally consistent with Mg isotopic data compiled for global arcs where magmas have Mg isotopic ratios ranging from mantle-like to ∼0.7 per mil above the mantle range, and compositions substantially below that range are rare. Thus, heavy Mg isotopes in the continents predicted by igneous and weathering fractionation might have been compensated by a hidden input of light Mg isotopes, which is presumably in the form of carbonates, leading to a bulk crustal Mg isotopic composition that is mantle-like. [ABSTRACT FROM AUTHOR]

Dehydration of subducting oceanic crust and underlying serpentinized mantle is potentially the most important source of fluids for element cycling between surface-processed materials and the interior of the Earth. Magnesium (Mg) isotopes -have been proposed as a promising tracer of dehydration of serpentinites because of their high Mg contents and distinctive Mg isotopic signatures relative to the mantle, which is difficult to identify using other isotopes. To constrain the primary controls on Mg isotope cycling in subduction zones, here we analyze a suite of well-characterized sub-arc mantle xenoliths from the Avacha volcano in southern Kamchatka arc, Russia. They are comparable in modal and/or chemical composition to serpentinized fore-arc harzburgites and sub-arc harzburgite xenoliths from the western Pacific. Despite evidence for ubiquitous slab-related fluid metasomatism, the 23 spinel harzburgite xenoliths and four pyroxenite metasomatic veins display mantle-like δ26Mg values from −0.30 to −0.21‰. Mineral separates have similar δ26Mg values, with an average of −0.26 ± 0.04‰ (2SD, n = 17) for olivine, −0.23 ± 0.04‰ (2SD, n = 17) for orthopyroxene, and −0.24 ± 0.10‰ (2SD, n = 5) for late-stage interstitial clinopyroxene. The lack of a clear slab-derived δ26Mg signature in the Avacha sub-arc peridotites is probably due to their high MgO contents and low fluid/rock mass ratios during flux melting and metasomatism. We also compare published δ26Mg data for four volcanic arcs distributed worldwide. This inter-arc comparison reveals that the thermal structure of a subduction zone appears to exert a strong control on the efficiency of Mg isotope cycling from the downgoing slab to the mantle wedge and subsequently to the arc magmas; those arcs that permit large-scale dehydration of Mg-rich serpentinized slab mantle, coupled with available channelized fluid pathways, are more likely to produce isotopically diverse arc magmas. [ABSTRACT FROM AUTHOR]

Substantial quantities of oceanic slabs are known to be recycled into the mantle through subduction. However, tracing their fate in the mantle through studies of mantle-derived samples is not always straightforward. As K represents an omnipresent element in subducting crustal materials, its two stable isotopes (39K and 41K) display outstanding potential in tracing recycled crustal materials in the mantle. Here we report the first set of K isotopic data for a suite of well-characterized continental basaltic lavas from Northeast China. The δ41K of these lavas exhibit large variation from −0.81‰ to −0.15‰, compared with the narrow range of unaltered oceanic basalts (−0.43 ± 0.03‰). The isotopic variations, together with geochemical data obtained in earlier studies, cannot be ascribed to chemical weathering, crystal fractionation, crustal contamination, or partial melting, but are consistent with the presence of diverse crustal materials in magma sources. Recycled oceanic crust and sediments both have contributed to the contrasting K isotopic signature observed in these lavas. Our study here highlights the potential of using K isotopes to trace different types of recycled crustal materials in the mantle and places new constraints on the generation of enriched mantle reservoirs. [ABSTRACT FROM AUTHOR]

Assessing the K isotopic composition of the upper continental crust is important for understanding the processes by which the crust is generated and modified, and constraining the K isotopic budget of the silicate Earth. High-precision K isotopic data are reported for 70 well-characterized individual and composite samples from the upper continental crust, including diorite, granodiorite, granite, loess, shale, graywacke, pelite, and tillite, to constrain its K isotopic composition. δ41K varies significantly in eight I-type and two S-type granites from Australia (−0.57 to −0.40‰), nine A-type granites (−0.53 to −0.38‰), and three granitoid composites including diorite, granodiorite, and granite (−0.50 to −0.37‰) from China, mainly reflecting source heterogeneity. The 22 post-Archean Australian shales (PAAS) (δ41K = −0.68 to −0.12‰) and the 12 sedimentary composites including graywacke, pelite, and tillite from China (δ41K = −0.57 to −0.23‰) have heterogeneous K isotopic compositions while the 12 loess samples from around the world display more limited K isotopic variation (δ41K = −0.47 to −0.35‰). δ41K values display a smaller dispersion in loess compared to shales, which have comparatively more intense weathering and higher chemical index of alteration (CIA). δ41K correlates with Fe 2 O 3 /Al 2 O 3 and Fe 2 O 3 /K 2 O in shales and Al 2 O 3 /SiO 2 , K 2 O/Al 2 O 3 , and δ7Li in loess, suggesting that K isotopes are fractionated during chemical weathering. Overall, the upper continental crust has a heterogeneous K isotopic composition, ranging from −0.68 to −0.12‰ with an average δ41K of −0.44 ± 0.05‰ (2SD, n = 88), which is indistinguishable from the mantle. [ABSTRACT FROM AUTHOR]

Precartilaginous stem cells (PCSCs) are adult stem cells that can initiate chondrocytes and bone development. In the present study, we explored whether miR-132/212 was involved in the proliferation of PCSCs via Hedgehog signaling pathway. PCSCs were isolated and purified with the fibroblast growth factor receptor-3 (FGFR-3) antibody. Cell viability, DNA synthesis and apoptosis were measured using MTT, BrdU and flow cytometric analysis. The mRNA and protein expression were detected by real-time PCR and Western blot, respectively. The target gene for miR-132/212 was validated by luciferase reporter assay. Results showed that transfection with miR-132/212 mimic significantly increased cell viability and DNA synthesis, and inhibited apoptosis of PCSCs. By contrast, miR-132/212 inhibitor could suppress growth and promote apoptosis of PCSCs. Luciferase reporter assays indicated that transfection of miR-132/212 led to a marked reduction of luciferase activity, but had no effect on PTCH1 3'-UTR mutated fragment, suggesting that Patched1 (PTCH1) is a target of miR-132/212. Furthermore, treatment with miR-132/212 mimics obviously increased the protein expression of Indian hedgehog (Ihh) and parathyroid hormone related protein (PTHrP), which was decreased after treatment with Hedgehog signaling inhibitor, cyclopamine. We also found that inhibition of Ihh/PTHrP signaling by cyclopamine significantly suppressed growth and DNA synthesis, and induced apoptosis in PCSCs. These findings demonstrate that miR-132/212 promotes growth and inhibits apoptosis in PCSCs by regulating PTCH1-mediated Ihh/PTHrP pathway, suggesting that miR-132/212 cluster might serve as a novel target for bone diseases. [ABSTRACT FROM AUTHOR]

In this paper, the interaction between an elastic plate and viscous fluids is numerically studied through a coupling lattice Boltzmann method with a finite element method. In simulations, the plate, which has a clamped trailing edge, is immersed in a linear shear flow of relatively low Reynolds numbers (Re). The dynamical analysis has been conducted in terms of aspect ratio (H), Reynolds number (Re), stiffness coefficient (K), and attack angle (β). Four generic modes for the plate motion or deformation are identified, and the respective characteristics are shown. Three maps of mode distributions depending on K, H, Re, and β are given definitely. Three routes for the plate to reach the deflected mode have been found. The elastic potential energy under different K numbers and aspect ratios H is compared. It is indicated that the larger aspect ratio would result in larger efficiency of energy transformation. It is also found that the flapping mode can only occur when the attack angle β ≥ 0°, i.e., if β < 0°, the plate merely remains in the deflected or straight mode. The vortex structures and the pressure distributions are shown clearly for flapping and deflected modes of the plate. The present results can provide useful information to the physical understanding of the dynamics for the plate motion in shear flows and can also offer additional knowledge about a flexible plate using energy from ambient fluids. [ABSTRACT FROM AUTHOR]

Rationale: The boron (B) isotopic composition in marine carbonates provides important insights into paleoclimate reconstruction and biomineralization. However, precise and accurate measurements of B isotopes using plasma‐based mass spectrometry is difficult due to the volatile nature of B, which typically requires complex and more specialized sample introduction systems. Existing analytical protocols have mostly been based on Thermo Scientific Neptune Plus multi‐collector inductively coupled plasma mass spectrometry (MC‐ICPMS) instruments, whereas methods based on Nu Plasma mass spectrometers are scarce. Methods: We have developed a simplified analytical protocol using Nu Plasma II MC‐ICPMS with standard glass sample introduction systems. Boron extraction and purification were conducted using a two‐stage column chemistry with cation‐exchange and Amberlite IRA 743 B‐specific resin. A sample drying step was avoided, which allows for direct isotopic analysis after column chemistry. A wet plasma mode with a standard glass cyclonic spray chamber and a glass nebulizer was used instead of a more specialized perfluoroalkoxy (PFA) sample introduction system. Low residual B signals were achieved with a relatively short period of wash‐out with 0.5 N HNO3. Results: The external precision is better than 0.30‰ (2SD) calculated from the long‐term bracketing standard, NIST SRM 951a. The overall robustness of the method was demonstrated by measurements of the international carbonate standard JCp‐1 (δ11B = +24.49 ± 0.36‰, 2SD) and seawater (δ11B = +39.98 ± 0.35‰), which are consistent with reported values. Conclusions: Our method provides an alternative approach for B isotope analysis using a routine wet plasma MC‐ICPMS setup that can facilitate geochemical and environmental application of B isotopes. [ABSTRACT FROM AUTHOR]

Abstract Fast pyrolysis, which is comparable with the enzyme or acid hydrolysis, should be considered for further development for fermentable levoglucosan (LG) production. This manuscript offers a broad review of the current status and future research perspectives of LG and its hydrolysates production from lignocellulosic biomass by fast pyrolysis for fermentation. The utilization, distribution and formation paths of LG from cellulose are presented. In consideration of the complexity of cellulose structure and lignocellulosic components, the influence of the major individual components (cellulose, hemicellulose, lignin and ash) and the structural properties (particle size, degree of polymerization and crystallinity) on the LG formation are reviewed. Aiming to further improve the yield of LG and the fermentability of pyrolysate, a number of pretreatment methods (e.g. hot-water pretreatment, acid pretreatment, acid impregnation) prior to fast pyrolysis, hydrolysis of LG and detoxification before fermentation, and microbial production of valuable products are also discussed in detail. At last, a brief conclusion for the challenge in this topic is provided. The low content of LG and the presentence of inhibitors to biocatalysts in the pyrolysate of lignocelluloses hamper the fermentable utilization of pyrolytic sugars, which need further investigation and improvement to make this process feasible. Graphical abstract fx1 Highlights • Levoglucosan (LG) from biomass by fast pyrolysis is reviewed in details. • Biomass components and structural properties on LG formation are presented. • Pretreatment techniques for fast hydrolysis are summarized. • Detoxification and hydrolysis of LG for fermentation are introduced. • Challenges for LG production and fermentation are proposed. [ABSTRACT FROM AUTHOR]

Highlights • Protein engineering realizes high activity and excretion of Ker in E. coli. • Rapid folding and maturation of Ker is essential for extracellular expression. • N-terminal propeptide engineering is highly efficient to obtain excellent Ker mutants. • Ker yield increased 9.26 times with feeding strategy in scale-up fermenter. Abstract Escherichia coli is one kind of the simple and excellent biosystem to overexpress heterologous enzymes, such as keratinolytic protease, an excellent enzyme to hydrolyze keratin substrate for broad industrial application. However, protein expression in E. coli frequently faces some problems such as inactive and inclusion body formation. This work described a series of protein engineering strategies of N-terminal propeptide replacement and site-directed mutagenesis to modify this enzyme activity and production. Site-directed mutagenesis (S180G/Y215S) on N-terminal propeptide altered mutant contributed to the highest specific activity (4725 ± 65 U/mg, more than 1300 U/mg improvement than wild-type enzyme). This comprehensive mutation also achieved 2.5-fold improvement of extracellular enzyme yield in shake-flask level. The fermentation strategies about optimizing glycerol feeding and inducing point in scale-up bioreactor resulted in tremendous leakage of keratinolytic protease (954 mg/L extracellular yield within 48 h, about 9.26-fold higher than the original shake-flask level) as well as cell lysis. Although this proposed strategy faces a major challenge to maintain cell integrity or viability, it still exists the opportunity to realize other enzymes extracellular expression in E. coli system and simplify downstream processing to meet the industrial application. [ABSTRACT FROM AUTHOR]