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To determine the value of obtaining additional preoperative imaging in patients with a traumatic hip fracture and a history of malignancy in whom plain radiographs show no lesion suspicious for metastases.Retrospective review.Teaching NHS Trust in the United Kingdom, over an 8-year period treating 4421 hip fractures.Three hundred sixty-seven patients with hip fracture and a history of malignancy at a site distant to the hip. Three hundred thirty patients had a history of trauma and no lesion on the plain radiograph suspicious for metastases.Whether obtaining additional imaging preoperatively (MRI, CT, and bone scan) identified metastases or affected management.32/330 patients had further preoperative imaging, none of which demonstrated a pathological fracture secondary to malignancy. On follow-up, 3/330 (0.9%) cases were found to have occult metastasis at the hip fracture site. All 3 had only plain radiographs before surgery. In 2, this was identified on histological examination of intraoperative samples, and in 1, radiologically as a metastatic metaphyseal lesion 18 months after a hemiarthroplasty. Only in the latter case, preoperative identification of hip metastasis could have altered surgical management. Patients undergoing further preoperative imaging waited significantly longer for surgery (35 ± 26 vs. 51 ± 26 hours, P = 0.0011).In the absence of a suspicious metastatic lesion on initial plain radiographs, further preoperative imaging is unlikely to identify a lesion that will affect management and confers significant delays to surgery. Sending intraoperative histological samples may help guide postoperative oncological management, but further work is needed to prove its utility.Diagnostic Level IV. See Instructions for Authors for a complete description of levels of evidence.

Electroencephalogram (EEG) and cerebrospinal fluid (CSF) are widely used in the clinical diagnosis of viral encephalitis (VE), but their value in the diagnosis of VE and the detection rate of abnormal indicators need to be further supported by more clinical data.In this study, routine laboratory testing, biochemical examinations of cerebrospinal fluid (CSF) and EEG characteristics were performed in patients with VE to guide the diagnosis and treatment of VE in clinical settings. A total of 330 patients with VE were enrolled in the Department of Neurology of the Third Affiliated Hospital of Zunyi Medical University from January 1, 2015 to January 30, 2020. EEG, routine testing and assessment of biochemical indicators of CSF were performed within 10 days after admission, and the results were analyzed by paired χ 2 test to compare the diagnostic value of EEG and CSF for VE.In 330 cases of VE, 283 cases (85.76%) had abnormal EEG, and 189 cases (57.27%) had abnormal CSF indicators. The incidence of EEG abnormalities was higher than that of CSF indicators, and the difference was statistically significant ( P0.05).Both the EEG and CSF analysis are valuable indicators in the diagnosis of VE patients. Compared with the CSF examination, the EEG examination had a better diagnostic efficacy for the diagnosis of VE. In addition, a normal EEG or a normal CSF level cannot exclude VE, and it is still necessary to develop new diagnostic indicators to cover all viral encephalitides.

Background: Esophageal cancer (ESCA) is a significant cause of tumor-related mortality worldwide. Cuproptosis is a novel cell death which is different from other regulate cell death, including ferroptosis, pyroptosis and apoptosis. However, the role of cuproptosis in the initiation and progression of ESCA remains unknown. Methods: The transcriptome data and clinical data of 173 patients with esophageal cancer in TCGA database were sorted and extracted with Perl software. Pearson correlation analysis was performed on cuproptosis related genes and all lncRNAs. The prognostic related lncRNAs were determined by univariate and multivariate Cox regression analysis, and a new prognostic model was constructed to calculate the risk score of each patient. C-Index curve, PCA analysis and ROC curve analysis were used to evaluate the prognosis prediction performance of 3- cuproptosis related lncRNAs (CRLs) model. In addition, multivariate Cox analysis was used to assess the prognostic value of the model in the entire cohort and in different subgroups. Results: The 3-CRLs risk scoring criteria including EWSAT1, AC125437.1 and GK-IT1 was established to evaluate the overall survival (OS) of ESCA. Survival analysis and ROC curve showed that the score had good prediction performance in TCGA train group and test group. The coefficients of each lncRNAs were analyzed using Lasso regression and lambda values were determined. principal component analysis was used to determine whether 3-CRLs can clearly distinguish the gap between high and low risk samples. Multivariate Cox regression showed that 3-CRLs characteristics were independent prognostic factors of OS. Norman map showed robust effectiveness in prognosis prediction. Conclusion: The risk characteristics based on 3-CRLs may be used to predict the prognosis of esophageal carcinoma patients

While functional materials with both light transmitting and electromagnetic shielding are highly desirable, only very few of them meet the stringent electromagnetic interference (EMI) shielding criteria for optoelectronic systems. Here, a design strategy of shorted micro-waveguides (SMWs) array to decouple the light transmission and EMI shielding is proposed and experimentally demonstrated. The array of SMWs, consisting of cut-off metallic micro-waveguides and shorting indium tin oxide (ITO) continuous conductive film, exhibits high optical transmittance of 90.4% and superior EMI shielding effectiveness of 62.2 dB on average over ultra-wide frequency spectrum (0.2-1.3 GHz & 1.7-18 GHz). Compared to previously reported works, an improvement of 19 dB in average shielding effectiveness has been achieved under the same level of light transmission, and the shielding frequency spectrum has been significantly expanded. The working principle has been explained in depth and factors influencing the performance have been investigated for design optimization.

Current landscape and potential future applications of artificial intelligence in medical physics and radiotherapy

One of the most cited limitations of biochemical detection is its poor sensitivity, owing to the relatively high complexity of micro-samples. Moreover, some samples cannot be easily self-replicated and their abundance cannot be increased through traditional technologies. Therefore, the preconcentration of low-abundance samples is a key requirement for microfluidic biological analysis. In recent years, the ion-concentration polarization phenomenon has aroused widespread interest in the application of microfluidic technology. In addition, paper-based materials are readily available, easy to modify, and exhibit good hydrophilicity. The study of the ion-concentration polarization preconcentration of micro-samples in paper-based microfluidic chips is of considerable significance. In this review, we discuss the development and applications of ion-concentration polarization paper-based preconcentrator in the past 5 years, with emphasis on key progresses in chip fabrication and performance optimization under different conditions. The current needs and development prospects in this field have also been discussed.

The adhesion of tumor cells to vascular endothelial cells is an important process of tumor metastasis. Studies have shown that tumor could educate vascular endothelial cells to promote tumor metastasis through many ways. However, the effect of tumor cells on the functions of vascular endothelial cells-derived extracellular vesicles (H-EVs) and the mechanisms underlying their effects in tumor-endothelium adhesion in metastasis remain mysterious. In this study, we found that H-EVs promoted the adhesion of triple negative breast cancer cell to endothelial cells and cirGal-3 enhanced the adhesion-promoting effects of H-EVs. The underlying mechanism was related to the upregulation of glycolysis in endothelial cells induced by cirGal-3 which led to the increase of the ICAM-1 expression and its transmission to MDA-MB-231 cells by H-EVs. Targeting of cirGal-3 or glycolysis of vascular endothelium in breast cancer therefore represents a promising therapeutic strategy to reduce metastasis.

Glutamine, as the most abundant amino acid in the body, participates in the biological synthesis of nucleotides and other non-essential amino acids in the process of cell metabolism. Recent studies showed that glutamine metabolic reprogramming is an important signal during cancer development and progression. This metabolic signature in cancer cells can promote the development of cancer by activating multiple signaling pathways and oncogenes. It can also be involved in tumor immune regulation and promote the development of drug resistance to tumors. In this review, we mainly summarize the role of glutamine metabolic reprogramming in tumors, including the regulation of multiple signaling pathways. We further discussed the promising tumor treatment strategy by targeting glutamine metabolism alone or in combination with chemotherapeutics.

It is generally believed that few-layer films of wurtzite materials remove the destabilizing dipole by converting to a flat hexagonal structure. However, using first-principles calculations, we demonstrate that contrary to the existing consensus these few-layer hexagonal films exhibit a small symmetric rumpling and are not perfectly flat. We then perform a systematic study of the rumpling behavior of a range of few-layer III-V and II-VI films. The symmetric rumpled configuration enables such films to cancel out the dipole and thereby to avoid the polar instability. This stabilization mechanism is quite distinct from those known for bulk and few-layer polar materials. Compared to the perfectly flat films, the rumpled films exhibit lower electrostatic potential energy, lower total energy, higher bonding strength, and thus greater stability and larger band gaps. We also discuss the relationship between rumpling behavior, interlayer interactions, and ionicity through electrostatic analysis.

Mn-based aqueous zinc-ion batteries (ZIBs) are promising candidate for large-scale rechargeable energy storage because of easy fabrication, low cost, and high safety. Nevertheless, the commercial application of Mn-based cathode is hindered by the challenging issues of low rate capability and poor cyclability. Herein, a manganese-vanadium hybrid, K-V2C@MnO2 cathode, featured with MnO2 nanosheets uniformly formed on a V2CTX MXene surface, is elaborately designed and synthesized by metal-cation intercalation and following in situ growth strategy. Benefiting from the hybrid structure with high conductivity, abundant active sites, and the synergistic reaction of Mn2+ electrodeposition and inhibited structural damage of MnO2, K-V2C@MnO2 shows excellent electrochemical performance for aqueous ZIBs. Specifically, it presents the high specific capacity of 408.1 mAh g-1 at 0.3 A g-1 and maintains the specific capacity of 119.2 mAh g-1 at a high current density of 10 A g-1 in a long-term cycle of up to 10000 cycles. It is superior to almost all reported Mn-based cathodes for ZIBs in the aqueous electrolyte. The superior electrochemical performance suggests that the Mn-based cathode materials designed in this work can be a rational approach to be applied for high-performance ZIBs cathodes.

Ternary compound CuSbSe2-alloyed PbTe, CumPb100SbmTe100Se2m (CLAST), presents outstanding n-type thermoelectric transport behavior and features hierarchical Cu-based precipitates and interstitials that can balance phonon and carrier transport. Results show that a small amount of CuSbSe2 (∼3%) alloying in CLAST can realize a room-temperature carrier concentration of ∼1.7 × 1018 cm−3 and then optimize the power factor, and simultaneously precipitate out embedded Cu-based nanostructures in the matrix to lower the lattice thermal conductivity. Additionally, extra Cu atoms adding in CLAST can form interstitials and further improve both the carrier concentration to ∼3.0 × 1018 cm−3 and carrier mobility to ∼1227.8 cm2 V−1 s−1 at room temperature, which benefits a maximum power factor of ∼20.0 μW cm−1 K−2 in Cu3.3Pb100Sb3Te100Se6. Moreover, the Cu interstitials together with massive Cu-based nanoprecipitates can strongly scatter a wide set of phonons, and largely lower the lattice thermal conductivity to ∼0.44 W m−1 K−1 in Cu3.4Pb100Sb3Te100Se6 at 623 K. Finally, these Cu-based hierarchical structures in CLAST samples can synergistically optimize the phonon and carrier transport properties and contribute to a high ZT of ∼0.5 at 300 K and a peak ZT of ∼1.4 at 723 K. A remarkably high ZTave of ∼0.94 at 300–723 K is achieved in Cu3.3Pb100Sb3Te100Se6 due to high ZT values in the low temperature range, outperforming other high-performance n-type PbTe-based thermoelectric materials.

Previous calculations of the dielectric and optical properties of 2D materials often overlooked or circumvented the influence of vacuum spacing introduced in periodic calculations, which gave rise to mispredictions of the intrinsic properties of 2D materials or merely qualitative results. We first elucidated the relationship between the vacuum spacing and the dielectric and optical properties of 2D materials in periodic calculations, and then formulated an effective method to accurately predict the dielectric and optical properties of 2D materials by restoring the intrinsic dielectric functions of 2D materials independent of the additional vacuum spacing. As examples, the intrinsic dielectric and optical properties of ultrathin hexagonal boron nitride (h-BN) and molybdenum sulphide (MoS2) from a monolayer to a pentalayer, including dielectric functions, optical absorption coefficients, refraction indexes, reflectivities, extinction coefficients, and energy loss functions, have been calculated by our method. Our calculations reveal that the out-of-plane optical dielectric constants, static refraction indexes, and static reflectivities of 2D h-BN and MoS2 increase as the number of layers increases, while the in-plane counterparts remain unchanged. The excitonic frequency-dependent optical properties of h-BN and MoS2 from a monolayer to bulk are also calculated by solving the Bethe–Salpeter equation and they show strong anisotropy. The present method shows better agreement with the experimental results compared to previous calculations and demonstrates enormous potential to investigate the dielectric and optical properties of other 2D materials extensively and quantitatively.

Aqueous zinc-ion batteries (ZIBs) are considered as desirable large-scale energy storage systems because of their environment friendliness and low cost. However, the development of ZIBs with stable performance still faces many obstacles before becoming viable for commercial applications. Herein, ZnxV2O5·nH2O nanobelts with uniform size derived from highly conductive V2CTx MXene (VC–ZVO) are designed and synthesized as cathodes for ZIBs via simultaneous ion intercalation and oxidation. Thanks to the pre-intercalated Zn2+ and the ubiquitous interfaces between ZVO and the conductive network composed of the remaining V2CTx and carbon, the charge redistribution in the active/conductive heterostructure leads to weakening of electrostatic interactions, quick zinc-ion insertion/extraction, and structural stability. Accordingly, the VC–ZVO electrode shows ultrastable cycling performance and high rate capacities for ZIBs, presenting no fading capacity at 0.1 A g−1 and 96.4% capacity retention over 8000 cycles at 10 A g−1. Further studies on the electrochemical kinetics and reaction mechanism elucidate faster Zn2+ diffusion and the high reversibility of VC–ZVO ZIBs. The revelation of the origin of the improved Zn2+-storage provides distinctive ideas for the enhancement of V-based electrodes and the development of a new type of cathode.

Background: The increased bone loss after spinal cord injury (SCI) is associated with an increase in the morbidity and mortality of fragility fractures, which can constitute a substantial cost to health care systems. Bisphosphonates (BPs) are now the principal class of medications used for osteoporosis. Objective: To demonstrate the effect of BPs on treating osteoporosis after SCI. Methods: A comprehensive search in PubMed, EMBASE, Web of Science and Cochrane Central databases was undertaken for randomized controlled trials (RCTs), exploring the effect of BPs on osteoporosis after SCI. The primary outcome measures were the BMD of different locations, serum bone turnover marker levels, serum biochemistry marker levels and adverse effect (AE) risks. The final search was performed in September 2019. Reporting was carried out according to PRISMA Guidelines. Results: Six RCTs were included. A total of 147 patients met the inclusion criteria. BPs were found to statistically prevent bone loss in the total hip, femoral neck and trochanter at the 6- and 12-month follow-up points and to increase the BMD of the lumbar spine at the 12-month follow-up time point. BPs had no clear effect on serum PINP or serum calcium levels at the 12-month follow-up time point. Conclusion: BP therapy may prevent bone loss in the lumbar spine and hip when administered early after SCI and has relatively high safety.

Calculations of transient thermal loads/boundary conditions are crucial for accurate thermal simulations of motorized spindle unit with time-varying working parameters (such as rotation speed). By the ELM theory, this paper proposes a modeling and calculation method onto transient thermal loads/boundary conditions for spindle simulation, according to spindle temperature detections. Firstly, heat-fluid-solid coupling finite element model is established to simulate spindle thermal behaviors. Secondly, the relationship between the real-time simulated spindle temperatures and the corresponding transient thermal loads/boundary conditions are constructed by ELM method. With real-time experimental temperatures being the input vector, transient thermal loads/boundary conditions for simulation are calculated by the established ELM model. Ultimately, with the spindle operation with progressive rotation being an example, the reliability of the proposed method is verified by the agreement between simulated spindle temperatures and their detections. Furthermore, obtained transient thermal loads/boundary conditions and simulation results are utilized to analyze spindle pure heat absorption, for the guidance onto spindle coolant strategy optimization.

The rising demand for energy density of cathodes means the need to raise the voltage or capacity of cathodes. Transition metal (TM) doping has been employed to enhance the electrochemical properties in multiple aspects. The redox voltage of doped cathodes usually falls in between the voltage of undoped layered cathodes. However, we found anomalous redox features in NaTi

Perovskite-related materials with various dimensionalities have attracted sustained attention owing to their extraordinary electronic and optoelectronic properties, but it is still challenging in the synthesis of compounds with desired compositions and structures. Herein, a two-dimensional (2D) CsPb

Although photodynamic therapy (PDT) has been extensively studied as an established modality of cancer treatment, it still suffers from a few clinical limitations, such as skin phototoxicity and tumor hypoxia. To circumvent these hurdles, hollow silica mesoporous nanoparticles (HMSNs) loaded with photosensitizers were employed as the nanoplatform to construct multifunctional nanoparticles (NPs). Specifically, an ultra-uniform polydopamine (PDA) shell was highly controlled grown around HMSNs by photogenerated outwards-diffused

In this study, octahedral molecular sieve (OMS-2) is successfully delaminated by using trace holmium (Ho) via a facile redox co-precipitation route, which exhibits high performance for the total toluene oxidation at low temperature. High resolution transmission electron microscope (HRTEM), X-ray photoelectron spectroscopy (XPS) and electron paramagnetic resonance (EPR) analyses verify that abundant multi-phase interfaces and lattice dislocations are formed on the obtained delaminated OMS-2 by the Ho (Ho-OMS-2), which can induce more active oxygen species. In particular, the delaminated OMS-2 with a trace Ho amount has a high Oads/Olatt ratio with a balanced ratio of Mn3+ and Mn4+, demonstrating much higher activity (T100% of 228 °C even under 5 vol% H2O vapor over 0.5% Ho-OMS-2) than the parent OMS-2 (T100% of 261 °C) for the total toluene oxidation. Furthermore, the positive effect of the introduction of H2O on catalytic activity, especially the enhancement of the conversion of intermediates into CO2 and H2O, is verified by the in situ diffuse reflection infrared Fourier transform spectroscopy (DRIFTS). Based on these results, the reaction mechanism for toluene oxidation over the OMS-2 based catalyst is proposed. It is expected to provide an effective preparation method to obtain high-performance catalysts for the VOCs oxidation at low temperatures.

The present work exemplifies complementary perspectives offered by the band and bond pictures of solids, with an emphasis on the chemical intuition pertaining to the latter, especially in the presence of interfaces. The modern computational method of constructing a unique set of maximally localized Wannier functions from delocalized band states imparts new interpretations to the familiar concept of chemical bonds in the context of crystalline solids. By bridging the band and bond pictures using advanced computational tools, we reveal for the first time the unusual bond characters of a long-predicted fivefold coordinated structure of binary octet compounds ANB8−N consisting of AA′ stacked planar AB honeycombs. While the isolated monolayer retains the familiar pz–π bonding in a honeycomb framework as in graphene and hexagonal boron nitride, the bulk foregoes in-plane π bonding and embraces out-of-plane ⋯A–B–A–B⋯ chain bonding via overlapping pz orbitals. Not only does the chemical intuition gained by invoking the bond picture clarify the chemical nature of the fivefold coordination, but it also facilely explains a salient discrepancy in theoretical predictions in otherwise sound ample experimental evidence in the form of epitaxial thin films, paving the way towards rational synthesis of such thin films for optoelectronic applications. On the other hand, we show that the conduction band minimum, important in determining the electrical and optical properties, is a distinctly extended state that can only be properly described within the band picture., A refreshed view of chemical bonds in solids unveils unusual bonding in fivefold coordinated bulk crystals of octet compounds: out-of-plane cation–anion chain bonding via overlapping pz orbitals replaces in-plane π bonding of the isolated monolayer.

Tuning the electrical transport behavior and reducing the Schottky barrier height of nanoelectronic devices remain a great challenge. To solve this issue, the electronic properties and Schottky barrier of the graphene/WSe2 heterostructure are investigated by the first-principles method under out-of-plane strain and an electric field. Our results show that the WSe2 monolayer and graphene could form a stable van der Waals heterostructure and the intrinsic electronic properties are well preserved. Furthermore, a transformation of a Schottky contact from the n-type to p-type occurs at d = 3.87 A and E = +0.06 V A−1. In addition, an ohmic contact is formed with E = −0.50, ±0.60 V A−1. Lastly, the effective masses of electrons and holes are calculated to be 0.057m0 and −0.055m0 at the equilibrium state, respectively, indicating that the heterostructure has a high carrier mobility. Our research will provide promising approaches for the future design and development of graphene/WSe2 nano-field effect transistors.

A peer-coaching approach was adopted in the out-of-class stage of the flipped classroom. Out of the classroom, learning tutors help students engage in learning and improve performance. Eighty-seven...

Determination of the structures of materials involving more light elements such as boron-rich compounds is challenging and technically important in understanding their varied compositions and super...

Transparent conducting oxides (TCO) with high electrical conductivity and high visible light transparency are desired for a wide range of high-impact engineering. Yet, usually, a compromise must be made between conductivity and transparency, limiting the practical application of a TCO to the next level. Furthermore, TCO performance is highly sensitive to composition, so conventional synthesis methods, such as chemical doping, cannot unravel the mysteries of the quantitative structure-performance relationship. Thus, improving the fundamental understanding or creating materials-by-design has limited success. Here, a strategy is proposed to modulate the lattice and electronic and optical properties precisely by applying pressure on a TCO. Strikingly, after compression-decompression treatment on the indium titanium oxides (ITiO), a highly transparent and metastable phase with two orders of magnitude enhancement in conductivity is synthesized from an irreversible phase transition. Moreover, this phase possesses previously unattainable filter efficiency on hazardous blue light up to 600 °C, providing potential for healthcare-related applications with strong thermal stability up to 200 °C. These results demonstrate that pressure engineering is a clean and effective tool for tailoring functional materials that are not achievable by other means, providing an exciting alternative property-tuning dimension in materials science.

Previous calculations of the dielectric and optical properties of 2D materials often overlooked or circumvented the influence of vacuum spacing introduced in periodic calculations, which gave rise to mispredictions of the intrinsic properties of 2D materials or merely qualitative results. We first elucidate the relationship between the vacuum spacing and the dielectric and optical properties of 2D materials in periodic calculations, and then bring forward an effective method to accurately predict the dielectric and optical properties of 2D materials by restoring the intrinsic dielectric functions of 2D materials independent of the additional vacuum spacing. As examples, the intrinsic dielectric and optical properties of ultrathin h-BN and MoS2 from monolayer to pentalayer, including dielectric functions, optical absorption coefficients, refraction indexes, reflectivities, extinction coefficients, and energy loss functions, have been calculated by our method. Our calculations reveal that the out-of-plane optical dielectric constants, static refraction indexes, and static reflectivities of 2D h-BN and MoS2 increase as the number of layers increases, while the in-plane counterparts remain unchanged. Excitonic frequency-dependent optical properties of h-BN and MoS2 from monolayer to bulk are also calculated by solving the Bethe-Salpeter equation and show strong anisotropy. In better agreement with experimental results than previous calculations, the presented method demonstrates enormous potential to investigate the dielectric and optical properties of other 2D materials extensively and quantitively.

KCTD15 is associated with body mass index and fat deposition in humans, mice and chickens. However, the function of KCTD15 in pig fat deposition remains unclear. In this study, we cloned and analysed the cDNA sequence of porcine KCTD15. The full length of the mRNA sequence of KCTD15 is 4,091 bp, encoding 283 amino acids. The protein is hydrophilic, it has a relative molecular mass of about 31.9 kDa and an isoelectric point of 7.09 with no signal peptide sequence or transmembrane structure. Expression analysis showed that KCTD15 expression level was significantly higher in the tissues of Large White pigs (LW) than in those of Tibetan pigs (TP) and Diannan Small-ear pigs (DN) at 6 months of age, whereas its expression level in embryonic tissues of LW at 60 days was lower than that in tissues of TP and Wujin pigs (WJ). In pig primary adipocytes, the expression level of KCTD15 is high in the early stage of differentiation and gradually decreases in later stages. Additionally, the single-nucleotide polymorphism (SNP) site T-2030C (T/C mutation, located 2,030 bp upstream of the start codon) showed a dominant allele T with high promoter activity in the LW population and a dominant allele C in the TP and WJ populations. Our results indicate that KCTD15 is involved in pig fat deposition and that T-2030C is an important regulatory site for transcriptional activity, affecting fat deposition.

Retinal ganglion cell axons are heavily myelinated (98%) and myelin damage in the optic nerve (ON) severely affects vision. Understanding the molecular mechanism of oligodendrocyte progenitor cell (OPC) differentiation into mature oligodendrocytes will be essential for developing new therapeutic approaches for ON demyelinating diseases. To this end, we developed a new method for isolation and culture of ON-derived oligodendrocyte lineage cells and used it to study OPC differentiation. A critical aspect of cellular differentiation is macroautophagy/autophagy, a catabolic process that allows for cell remodeling by degradation of excess or damaged cellular molecules and organelles. Knockdown of ATG9A and BECN1 (pro-autophagic proteins involved in the early stages of autophagosome formation) led to a significant reduction in proliferation and survival of OPCs. We also found that autophagy flux (a measure of autophagic degradation activity) is significantly increased during progression of oligodendrocyte differentiation. Additionally, we demonstrate a significant change in mitochondrial dynamics during oligodendrocyte differentiation, which is associated with a significant increase in programmed mitophagy (selective autophagic clearance of mitochondria). This process is mediated by the mitophagy receptor BNIP3L (BCL2/adenovirus E1B interacting protein 3-like). BNIP3L-mediated mitophagy plays a crucial role in the regulation of mitochondrial network formation, mitochondrial function and the viability of newly differentiated oligodendrocytes. Our studies provide novel evidence that proper mitochondrial dynamics is required for establishment of functional mitochondria in mature oligodendrocytes. These findings are significant because targeting BNIP3L-mediated programmed mitophagy may provide a novel therapeutic approach for stimulating myelin repair in ON demyelinating diseases. Abbreviations: A2B5: a surface antigen of oligodendrocytes precursor cells, A2B5 clone 105; ACTB: actin, beta; APC: an antibody to label mature oligodendrocytes, anti-adenomatous polyposis coli clone CC1; ATG5: autophagy related 5; ATG7: autophagy related 7; ATG9A: autophagy related 9A; AU: arbitrary units; BafA1: bafilomycin A1; BCL2: B cell leukemia/lymphoma 2; BECN1: beclin 1, autophagy related; BNIP3: BCL2/adenovirus E1B interacting protein 3; BNIP3L/NIX: BCL2/adenovirus E1B interacting protein 3-like; CASP3: caspase 3; CNP: 2′,3′-cyclic nucleotide 3′-phosphodiesterase; Ctl: control; COX8: cytochrome c oxidase subunit; CSPG4/NG2: chondroitin sulfate proteoglycan 4; DAPI: 4′6-diamino-2-phenylindole; DNM1L: dynamin 1-like; EGFP: enhanced green fluorescent protein; FACS: fluorescence-activated cell sorting; FIS1: fission, mitochondrial 1; FUNDC1: FUN14 domain containing 1; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; GFAP: glial fibrillary growth factor; GFP: green fluorescent protein; HsESC: human embryonic stem cell; IEM: immunoelectron microscopy; LAMP1: lysosomal-associated membrane protein 1; LC3B: microtubule-associated protein 1 light chain 3; MBP: myelin basic protein; MFN2: mitofusin 2; Mito-Keima: mitochondria-targeted monomeric keima-red; Mito-GFP: mitochondria-green fluorescent protein; Mito-RFP: mitochondria-red fluorescent protein; MitoSOX: red mitochondrial superoxide probe; MKI67: antigen identified by monoclonal antibody Ki 67; MMP: mitochondrial membrane potential; O4: oligodendrocyte marker O4; OLIG2: oligodendrocyte transcription factor 2; ON: optic nerve; OPA1: OPA1, mitochondrial dynamin like GTPase; OPC: oligodendrocyte progenitor cell; PDL: poly-D-lysine; PINK1: PTEN induced putative kinase 1; PRKN/Parkin: parkin RBR E3 ubiquitin protein ligase; RFP: red fluorescent protein; RGC: retinal ganglion cell; ROS: reactive oxygen species; RT-PCR: real time polymerase chain reaction; SEM: standard error of the mean; SOD2: superoxide dismutase 2, mitochondrial; SQSTM1/p62: sequestosome 1; TEM: transmission electron microscopy; TMRM: tetramethylrhodamine methyl ester; TOMM20: translocase of outer mitochondrial membrane 20; TUBB: tubulin, beta; TUBB3: tubulin, beta 3 class III.

Bone loss is one of the most serious medical problem associated with prolonged weightlessness in long-term spaceflight mission. Skeletal reloading after prolonged spaceflight have indicated incomplete recovery of lost bone, which may lead to an increased risk of fractures in astronauts when returning to Earth. Substantial studies have revealed the capacity of static magnetic fields (SMFs) on treating various bone disorders, whereas it is unknown whether SMFs have the potential regulatory effects on bone quality in unloaded mice during unloading. This study was conducted to investigate the potential effects of whole-body SMF exposure with 0.2 ∼ 0.4 T on the recovery of unloading-induced bone loss. Eight‐week‐old male C57BL/6J mice were subjected to hindlimb unloading (HLU) for 4 weeks, following the mice were reloaded for 4 weeks under geomagnetic field (GMF) and SMF of 0.2 ∼ 0.4 T. Bone quality indexes, including bone mineral density (BMD) and bone mineral content (BMC), bone microarchitecture, and bone mechanical properties were examined by the measurement of dual energy X-ray absorptiometry (DEXA), micro-computed tomography (Micro-CT), and 3-point bending. Bone turnover was evaluated by bone histomorphometric and serum biochemical assay. We found that SMF exposure for 4 weeks significantly promoted the recovery in HLU-induced decrease of BMD and BMC, deterioration of bone microarchitecture, and reduction of bone strength. The results from bone turnover determination revealed that SMF exposure for 4 weeks induced lower osteoclast number of trabecular bone and serum TRAP-5b levels in reloaded mice, whereas SMF showed no significant alteration in skeletal osteoblast number and serum osteocalcin levels. Together, our findings suggest that SMF of 0.2 ∼ 0.4 T facilitated the recovery of unloading-induced bone loss by inhibiting the increase of bone resorption in reloaded mice, and indicate that SMF might become a promising biophysical countermeasure for maintaining bone health in astronauts after landing.

For a sustainable energy system, large-scale hydrogen production under intermittent renewable energy sources from solar and natural wind system are currently necessary. However, the price of noble metal-based catalysts and their poor stability limit their large-scale application. Herein, a Ni3S2@NiCo-LDH composite electrocatalysts with a core@shell structure was successfully synthesized via an in-situ hydrothermal method coupling with an electrodeposition process. The obtained Ni3S2@NiCo-LDH/NF electrode exhibited superb OER performance with low overpotentials of 305 and 346 mV to deliver current densities of 50 and 100 mA cm-2, respectively. Meanwhile, this electrode also stabilized at 100 mA cm-2 in the alkaline solution at both continuous and intermittent conditions without degradation for over 24 hours. The remarkable electrocatalytic activity should be attributed to the unique morphology of nano-grasses (core) with nanoflake structure (shell) with a high density of exposed active sites, rich defects and large surface areas. This electrocatalyst design could be applied for the large-scale hydrogen production using electricity generated from intermittent renewable energy.

Structural and phonon properties, formation and cohesive energies, and electronic structures of ${\mathrm{II}}_{A}$-IV-${\mathrm{N}}_{2}$ (where ${\mathrm{II}}_{\mathrm{A}}=\mathrm{Be}$ or Mg; $\mathrm{IV}=\mathrm{Si}$, Ge, or Sn) monolayers with a graphenelike planar structure are systematically studied. Stability and property evolution with the variation of constituent group ${\mathrm{II}}_{A}$ and group IV elements are revealed. Dynamical and elastic stability of ${\mathrm{II}}_{A}$-IV-${\mathrm{N}}_{2}$ monolayers is justified by phonon and elasticity calculations, respectively. Their wide band gaps ranging from 3.32 to 5.61 eV are predicted by the $GW$ method on top of density functional calculations. The fat-band analysis and charge-density calculation of selected eigenstates unveil the effect of chemical environment and elemental substitution on electronic states near the band-gap region. The quasi-free-electron state and the parabolic dispersion of the lowest conduction band are advantageous for electron transport in electronic applications. A close examination of the band alignment and structural similarity between monolayers of ${\mathrm{II}}_{A}$-IV-${\mathrm{N}}_{2}$ compounds and III nitrides indicates that it is possible to form type-I or type-II heterostructures and alloy systems composed of monolayers of ${\mathrm{II}}_{A}$-IV-${\mathrm{N}}_{2}$ compounds and III nitrides. The findings in this work will promote research aiming at the synthesis, characterization, and application of novel two-dimensional materials, alloys, and heterostructures.

Using high-resolution transmission electron microscopy and electron energy-loss spectroscopy, we show that beryllium oxide crystallizes in the planar hexagonal structure in a graphene liquid cell by a wet-chemistry approach. These liquid cells can feature van-der-Waals pressures up to 1 GPa, producing a miniaturized high-pressure container for the crystallization in solution. The thickness of as-received crystals is beyond the thermodynamic ultra-thin limit above which the wurtzite phase is energetically more favorable according to the theoretical prediction. The crystallization of the planar phase is ascribed to the near-free-standing condition afforded by the graphene surface. Our calculations show that the energy barrier of the phase transition is responsible for the observed thickness beyond the previously predicted limit. These findings open a new door for exploring aqueous-solution approaches of more metal-oxide semiconductors with exotic phase structures and properties in graphene-encapsulated confined cells.

赣杭铀成矿带是我国最大的火山岩型铀成矿带，大茶园（661）铀矿床是该成矿带东段最重要的火山岩型铀矿床，矿体赋存于晚中生代磨石山群九里坪组流纹岩中。为探讨该铀矿床成矿物质来源，对采自大茶园铀矿床中的脉石矿物开展了系统的C-O和Sr-Nd同位素研究。结果表明，成矿流体中矿化剂∑CO2主要来源于地幔，部分来自于基底大理岩或沉积碳酸盐岩碳；成矿期后方解石碳同位素组成靠近基底大理岩或沉积碳酸盐岩组成，可能主要为壳源碳酸盐岩的贡献；成矿期流体中∑CO2以HCO3-为主，CO2去气作用为方解石沉淀形成的主要机制。成矿期不同阶段方解石与萤石的Sr、Nd同位素组成没有明显差别且变化较小，显示矿床中脉石矿物的同源性。通过与基底陈蔡群变质岩和盖层火山岩的Sr、Nd同位素组成对比发现，成矿期萤石与盖层火山岩具有类似的Sr同位素组成，表明大茶园铀矿床成矿物质以壳源为主，主要来自于赋矿火山岩，而Nd同位素进一步表明成矿物质可能来源于赋矿的流纹岩。岩石圈伸展控制着富CO2热液的形成，富CO2热液在上升过程中萃取壳源（尤其是富铀火山岩）中成矿物质，并在有利的成矿部位通过CO2去气作用导致铀沉淀成矿。