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The specific capacity of Li- and Mn-rich layered oxide (LMROs) cathodes can be enhanced by the oxidation of lattice oxygen at high voltages. Nevertheless, an irreversible oxygen loss emerges with cycling, which triggers interlocking surface/interface issues and results in the fast deterioration of cycling performance. Herein, we prepare a surface modified LMRO electrode by one step doctor-blade casting and introducing a benzoquinone species DBBQ redox couple. The electrochemical test shows that the DBBQ-modified electrode has a high reversible capacity (>320 mAh g -1 ) and excellent rate performance, while the cyclic stability has been significantly improved as well. The capacity retention reaches as high as 93.3% after 500 cycles at 1 C. Mechanism analysis shows that DBBQ can not only play a redox couple in LMROs which achieves the adsorption and reduction of surface oxygen gas but also significantly enhance anionic redox in the bulk, thus realizing extraordinary capacity.

Context.—: Eosinophilic solid and cystic renal cell carcinoma is now defined in the 5th edition of the 2022 World Health Organization classification of urogenital tumors., Objective.—: To perform morphologic, immunohistochemical, and preliminary genetic studies about this new entity in China for the purpose of understanding it better., Design.—: The study includes 18 patients from a regional tertiary oncology center in northern China (Tianjin, China). We investigated the clinical and immunohistochemical features of these cases., Results.—: The mean age of patients was 49.6 years, and the male to female ratio was 11:7. Macroscopically, 1 case had the classic cystic and solid appearance, whereas the others appeared purely solid. Microscopically, all 18 tumors shared a similar solid and focal macrocystic or microcystic growth pattern, and the cells were characterized by voluminous and eosinophilic cytoplasm, along with coarse amphophilic stippling. Immunohistochemically, most of the tumors had a predominant cytokeratin (CK) 20-positive feature, ranging from focal cytoplasmic staining to diffuse membranous accentuation. Initially, we separated these cases into different immunohistochemical phenotypes. Group 1 (7 of 18; 38.5%) was characterized by positive phospho-4EBP1 and phospho-S6, which can imply hyperactive mechanistic target of rapamycin complex 1 (mTORC1) signaling. Group 2 (4 of 18; 23%) was negative for NF2, probably implying a germline mutation of NF2. Group 3 (7 of 18; 38.5%) consisted of the remaining cases. One case had metastatic spread and exhibited an aggressive clinical course, and we detected cyclin-dependent kinase inhibitor 2A (CDKN2A) mutation in this case; other patients were alive and without disease progression., Conclusions.—: Our research proposes that eosinophilic solid and cystic renal cell carcinoma exhibits prototypical pathologic features with CK20 positivity and has aggressive potential., Competing Interests: The authors have no relevant financial interest in the products or companies described in this article., (© 2024 College of American Pathologists.)

Anionic redox chemistry enables extraordinary capacity for Li- and Mn-rich layered oxides (LMROs) cathodes. Unfortunately, irreversible surface oxygen evolution evokes the pernicious phase transition, structural deterioration, and severe electrode-electrolyte interface side reaction with element dissolution, resulting in fast capacity and voltage fading of LMROs during cycling and hindering its commercialization. Herein, a redox couple strategy is proposed by utilizing copper phthalocyanine (CuPc) to address the irreversibility of anionic redox. The Cu-N synergistic effect of CuPc could not only inhibit surface oxygen evolution by reducing the peroxide ion O 2 2- back to lattice oxygen O 2- , but also enhance the reaction activity and reversibility of anionic redox in bulk to achieve a higher capacity and cycling stability. Moreover, the CuPc strategy suppresses the interface side reaction and induces the forming of a uniform and robust LiF-rich cathode electrolyte, interphase (CEI) to significantly eliminate transition metal dissolution. As a result, the CuPc-enhanced LMRO cathode shows superb cycling performance with a capacity retention of 95.0% after 500 long-term cycles. This study sheds light on the great effect of N-based redox couple to regulate anionic redox behavior and promote the development of high energy density and high stability LMROs cathode., (© 2024 Wiley‐VCH GmbH.)

The indirect exchange interaction between local magnetic moments via surface electrons has been long predicted to bolster the surface ferromagnetism in magnetic topological insulators (MTIs), which facilitates the quantum anomalous Hall effect. This unconventional effect is critical to determining the operating temperatures of future topotronic devices. However, the experimental confirmation of this mechanism remains elusive, especially in intrinsic MTIs. Here, we combine time-resolved photoemission spectroscopy with time-resolved magneto-optical Kerr effect measurements to elucidate the unique electromagnetism at the surface of an intrinsic MTI MnBi 2 Te 4 . Theoretical modeling based on 2D Ruderman-Kittel-Kasuya-Yosida interactions captures the initial quenching of a surface-rooted exchange gap within a factor of two but overestimates the bulk demagnetization by one order of magnitude. This mechanism directly explains the sizable gap in the quasi-2D electronic state and the nonzero residual magnetization in even-layer MnBi 2 Te 4 . Furthermore, it leads to efficient light-induced demagnetization comparable to state-of-the-art magnetophotonic crystals, promising an effective manipulation of magnetism and topological orders for future topotronics.

Solid tumours often endure nutrient insufficiency during progression. How tumour cells adapt to temporal and spatial nutrient insufficiency remains unclear. We previously identified STC2 as one of the most upregulated genes in cells exposed to nutrient insufficiency by transcriptome screening, indicating the potential of STC2 in cellular adaptation to nutrient insufficiency. However, the molecular mechanisms underlying STC2 induction by nutrient insufficiency and subsequent adaptation remain elusive. Here, we report that STC2 protein is dramatically increased and secreted into the culture media by Gln-/Glc- deprivation. STC2 promoter contains cis-elements that are activated by ATF4 and p65/RelA, two transcription factors activated by a variety of cellular stress. Biologically, STC2 induction and secretion promote cell survival but attenuate cell proliferation during nutrient insufficiency, thus switching the priority of cancer cells from proliferation to survival. Loss of STC2 impairs tumour growth by inducing both apoptosis and necrosis in mouse xenografts. Mechanistically, under nutrient insufficient conditions, cells have increased levels of reactive oxygen species (ROS), and lack of STC2 further elevates ROS levels that lead to increased apoptosis. RNA-Seq analyses reveal STC2 induction suppresses the expression of monoamine oxidase B (MAOB), a mitochondrial membrane enzyme that produces ROS. Moreover, a negative correlation between STC2 and MAOB levels is also identified in human tumour samples. Importantly, the administration of recombinant STC2 to the culture media effectively suppresses MAOB expression as well as apoptosis, suggesting STC2 functions in an autocrine/paracrine manner. Taken together, our findings indicate that nutrient insufficiency induces STC2 expression, which in turn governs the adaptation of cancer cells to nutrient insufficiency through the maintenance of redox homoeostasis, highlighting the potential of STC2 as a therapeutic target for cancer treatment., (© 2024. The Author(s).)

Ultrathin topological insulator membranes are building blocks of exotic quantum matter. However, traditional epitaxy of these materials does not facilitate stacking in arbitrary orders, while mechanical exfoliation from bulk crystals is also challenging due to the non-negligible interlayer coupling therein. Here we liberate millimeter-scale films of the topological insulator Bi 2 Se 3 , grown by molecular beam epitaxy, down to 3 quintuple layers. We characterize the preservation of the topological surface states and quantum well states in transferred Bi 2 Se 3 films using angle-resolved photoemission spectroscopy. Leveraging the photon-energy-dependent surface sensitivity, the photoemission spectra taken with 6 and 21.2 eV photons reveal a transfer-induced migration of the topological surface states from the top to the inner layers. By establishing clear electronic structures of the transferred films and unveiling the wave function relocation of the topological surface states, our work lays the physics foundation crucial for the future fabrication of artificially stacked topological materials with single-layer precision.

Currently, the alteration of external factors during crude oil extraction easily disrupts the thermodynamic equilibrium of asphaltene, resulting in the continuous flocculation and deposition of asphaltene molecules in crude oil. This accumulation within the pores of reservoir rocks obstructs the pore throat, hindering the efficient extraction of oil and gas, and consequently, affecting the recovery of oil and gas resources. Therefore, it is crucial to investigate the principles of asphaltene deposition inhibition and the synthesis of asphaltene inhibitors. In recent years, the development of nanotechnology has garnered significant attention due to its unique surface and volume effects. Nanoparticles possess a large specific surface area, high adsorption capacity, and excellent suspension and catalytic abilities, exhibiting unparalleled advantages compared with traditional organic asphaltene inhibitors, such as sodium dodecyl benzene sulfonate and salicylic acid. At present, there are three primary types of nanoparticle inhibitors: metal oxide nanoparticles, organic nanoparticles, and inorganic nonmetal nanoparticles. This paper reviews the recent advancements and application challenges of nanoparticle asphaltene deposition inhibition technology based on the mechanism of asphaltene deposition and nano-inhibitors. The aim was to provide insights for ongoing research in this field and to identify potential future research directions.

LiBH 4 is one of the most promising candidates for use in all-solid-state lithium batteries. However, the main challenges of LiBH 4 are the poor Li-ion conductivity at room temperature, excessive dendrite formation, and the narrow voltage window, which hamper practical application. Herein, we fabricate a flexible polymeric electronic shielding layer on the particle surfaces of LiBH 4 . The electronic conductivity of the primary LiBH 4 is reduced by 2 orders of magnitude, to 1.15 × 10 -9 S cm -1 at 25 °C, due to the high electron affinity of the electronic shielding layer; this localizes the electrons around the BH 4 - anions, which eliminates electronic leakage from the anionic framework and leads to a 68-fold higher critical electrical bias for dendrite growth on the particle surfaces. Contrary to the previously reported work, the shielding layer also ensures fast Li-ion conduction due to the fast-rotational dynamics of the BH 4 - species and the high Li-ion (carrier) concentration on the particle surfaces. In addition, the flexibility of the layer guarantees its structural integrity during Li plating and stripping. Therefore, our LiBH 4 -based solid-state electrolyte exhibits a high critical current density (11.43 mA cm -2 ) and long cycling stability of 5000 h (5.70 mA cm -2 ) at 25 °C. More importantly, the electrolyte had a wide operational temperature window (-30-150 °C). We believe that our findings provide a perspective with which to avoid dendrite formation in hydride solid-state electrolytes and provide high-performance all-solid-state lithium batteries.

LiBH 4 is a promising solid-state electrolyte (SE) due to its thermodynamic stability to Li. However, poor Li-ion conductivities at room temperature, low oxidative stabilities, and severe dendrite growth hamper its application. In this work, a partial dehydrogenation strategy is adopted to in situ generate an electronic blocking layer dispersed of LiH, addressing the above three issues simultaneously. The electrically insulated LiH reduces the electronic conductivity by two orders of magnitude, leading to a 32.0-times higher critical electrical bias for dendrite growth on the particle surfaces than that of the counterpart. Additionally, this layer not only promotes the Li-ion conductance by stimulating coordinated rotations of BH 4 - and B 12 H 12 2- , contributing to a Li-ion conductivity of 1.38 × 10 -3 S cm -1 at 25 °C, but also greatly enhances oxidation stability by localizing the electron density on BH 4 - , extending its voltage window to 6.0 V. Consequently, this electrolyte exhibits an unprecedented critical current density (CCD) of 15.12 mA cm -2 at 25 °C, long-term Li plating and stripping stability for 2700 h, and a wide temperature window for dendrite inhibition from -30 to 150 °C. Its Li-LiCoO 2 cell displays high reversibility within 3.0-5.0 V. It is believed that this work provides a clear direction for solid-state hydride electrolytes., (© 2023 Wiley-VCH GmbH.)

Objective: Solid tumor cells utilize amino acid transporters (AATs) to increase amino acid uptake in response to nutrient-insufficiency. The upregulation of AATs is therefore critical for tumor development and progression. This study identifies the upregulated AATs under amino acid deprived conditions, and further determines the clinicopathological importance of these AATs in evaluating the prognosis of patients with cancers., Materials and Methods: In this experimental study, the Gene Expression Omnibus (GEO) datasets (GSE62673, GSE26370, GSE125782 and GSE150874) were downloaded from the NCBI website and utilized for integrated differential expression and pathway analysis v0.96, Gene Set Enrichment Analysis (GSEA), and REACTOME analyses to identify the AATs upregulated in response to amino acid deprivation. In addition, The Cancer Genome Atlas (TCGA) datasets with prognostic information were assessed and employed to evaluate the association of identified AATs with patients' prognoses using SurvExpress analysis., Results: Using analysis of NCBI GEO data, this study shows that amino acid deprivation leads to the upregulation of six AAT genes; SLC3A2, SLC7A5, SLC7A1, SLC1A4, SLC7A11 and SLC1A5. GSEA and REACTOME analyses identified altered signaling in cells exposed to amino acid deprivation, such as pathways related to stress responses, the cell cycle and apoptosis. In addition, Principal Component Analysis showed these six AAT genes to be well divided into two distinct clusters in relation to TCGA tumor tissues versus normal counterparts. Finally, Log-Rank analysis confirmed the upregulation of this panel of six AAT genes is correlated with poor prognosis in patients with colorectal, esophageal, kidney and lung cancers., Conclusion: The upregulation of a panel of six AATs is common in several human cancers and may provide a valuable diagnostic tool to evaluate the prognosis of patients with colorectal, esophageal, kidney and lung cancers.

The efficient capture and immobilization of radioiodine (I - , IO 3 - ) is of great importance in radioactive waste management. Here, a Cu 2 O-loaded three-dimensional bulk cationic hydrogel composite (Cu 2 O@CH) was successfully prepared by simple redox reactions and UV photopolymerization, which realized the rapid enrichment and efficient immobilization of I - and IO 3 - . The adsorption experiments showed that the maximum adsorption capacity of Cu 2 O@CH for I - in the solution at pH = 3 reached 416.5 mg/g, and the adsorption capacity of IO 3 - in the solution at pH = 6 could reach 313.4 mg/g. It exhibited extremely fast adsorption kinetics for I - and IO 3 - . In addition, Cu 2 O@CH also exhibited efficient I - and IO 3 - removal from simulated high-level liquid waste. The rapid capture and effective immobilization of radioiodine (I - , IO 3 - ) were realized by the electrostatic interaction of -N + (CH 3 ) 3 groups in Cu 2 O@CH with I - and IO 3 - , as well as the chemical reactions between Cu 2 O and I - . The bulk cationic hydrogel composite explored the multifunctional role toward fast, high adsorption capability and easy handling, highlighting its superiority compared to the powder adsorbent, which renders it a potential adsorbent for the removal of radioactive iodine (I - , IO 3 - ) in nuclear wastewater treatment.

Background: Immunocheckpoint inhibitors (ICIs) have been widely used in the clinical treatment of lung cancer. Although clinical studies and trials have shown that patients can benefit significantly after PD-1/PD-L1 blocking therapy, less than 20% of patients can benefit from ICIs therapy due to tumor heterogeneity and the complexity of immune microenvironment. Several recent studies have explored the immunosuppression of PD-L1 expression and activity by post-translational regulation. Our published articles demonstrate that ISG15 inhibits lung adenocarcinoma progression. Whether ISG15 can enhance the efficacy of ICIs by modulating PD-L1 remains unknown., Methods: The relationship between ISG15 and lymphocyte infiltration was identified by IHC. The effects of ISG15 on tumor cells and T lymphocytes were assessed using RT-qPCR and Western Blot and in vivo experiments. The underlying mechanism of PD-L1 post-translational modification by ISG15 was revealed by Western blot, RT-qPCR, flow cytometry, and Co-IP. Finally, we performed validation in C57 mice as well as in lung adenocarcinoma tissues., Results: ISG15 promotes the infiltration of CD4 + T lymphocytes. In vivo and in vitro experiments demonstrated that ISG15 induces CD4 + T cell proliferation and invalidity and immune responses against tumors. Mechanistically, we demonstrated that the ubiquitination-like modifying effect of ISG15 on PD-L1 increased the modification of K48-linked ubiquitin chains thus increasing the degradation rate of glycosylated PD-L1 targeting proteasomal pathway. The expression of ISG15 and PD-L1 was negatively correlated in NSCLC tissues. In addition, reduced accumulation of PD-L1 by ISG15 in mice also increased splenic lymphocyte infiltration as well as promoted cytotoxic T cell infiltration in the tumor microenvironment, thereby enhancing anti-tumor immunity., Conclusions: The ubiquitination modification of PD-L1 by ISG15 increases K48-linked ubiquitin chain modification, thereby increasing the degradation rate of glycosylated PD-L1-targeted proteasome pathway. More importantly, ISG15 enhanced the sensitivity to immunosuppressive therapy. Our study shows that ISG15, as a post-translational modifier of PD-L1, reduces the stability of PD-L1 and may be a potential therapeutic target for cancer immunotherapy., (© 2023. The Author(s).)

The low efficient transfer of photogenerated electrons to an active catalytic site is a pivotal problem for the photoreduction of highly soluble hexavalent uranium [U(VI)] to low soluble tetravalent uranium [U(IV)]. Herein, we successfully synthesized a TiO 2- x /1T-MoS 2 /reduced graphene oxide heterojunction (T 2- x TMR) with dual charge-transfer channels by exploiting the difference in Fermi levels between the heterojunction interfaces, which induced multilevel separation of photogenerated carriers. Theoretical and experimental results demonstrate that the presence of the electron buffer layer promoted the efficient migration of photogenerated electrons between the dual charge-transfer channels, which achieved effective separation of photogenerated carriers in physical/spatial dimensions and significantly extended the lifetime of photogenerated electrons. The migration of photogenerated electrons to the active catalytic site after multilevel spatial separation enabled the T 2- x TMR dual co-photocatalyst to remove 97.4% of the high concentration of U(VI) from the liquid-phase system within 80 min. This work provides a practical reference for utilizing multiple co-catalysts to accomplish directed spatial separation of photogenerated carriers.

Tailoring magnetic orders in topological insulators is critical to the realization of topological quantum phenomena. An outstanding challenge is to find a material where atomic defects lead to tunable magnetic orders while maintaining a nontrivial topology. Here, by combining magnetization measurements, angle-resolved photoemission spectroscopy, and transmission electron microscopy, we reveal disorder-enabled, tunable magnetic ground states in MnBi 6 Te 10 . In the ferromagnetic phase, an energy gap of 15 meV is resolved at the Dirac point on the MnBi 2 Te 4 termination. In contrast, antiferromagnetic MnBi 6 Te 10 exhibits gapless topological surface states on all terminations. Transmission electron microscopy and magnetization measurements reveal substantial Mn vacancies and Mn migration in ferromagnetic MnBi 6 Te 10 . We provide a conceptual framework where a cooperative interplay of these defects drives a delicate change of overall magnetic ground state energies and leads to tunable magnetic topological orders. Our work provides a clear pathway for nanoscale defect-engineering toward the realization of topological quantum phases.

When a metal makes contact with a band insulator, charge transfer occurs across the interface leading to band bending and a Schottky barrier with rectifying behavior. The nature of metal-Mott insulator junctions, however, is still debated due to challenges in experimental probes of such vertical heterojunctions with buried interfaces. Here, we grow lateral polymorphic heterostructures of single-layer metallic 1H and Mott insulating 1T NbSe 2 by molecular beam epitaxy. We find a one-dimensional metallic channel along the interface due to the appearance of quasiparticle states with an intensity decay following 1/ x 2 , indicating an impenetrable barrier. Near the interface, the Mott gap exhibits a strong spatial dependence arising from the difference in lattice constants between the two phases, consistent with our density functional theory calculations. These results provide clear experimental evidence for an impenetrable barrier at the metal-Mott insulator junction and the high tunability of a Mott insulator by strain.

Li-rich Mn-based layered oxides (LMLOs) are promising cathode material candidate for the next-generation Li-ion batteries (LIBs) of high energy density. However, the fast capacity fading and voltage decay as well as low Coulombic efficiency caused by irreversible oxygen release and phase transition during the electrochemical process hinder their practical application. To solve these problems, in the present study, a multifunctional surface construction involving a coating layer, spinel-layered heterostructure, and rich-in oxygen vacancies is successfully conducted by a facile thermal reduction of the LMLO particles with potassium borohydride (KBH 4 ) as the reducing agent. The multifunctional surface structure plays synergistic effects on suppressing the interface side reaction, reducing the dissolution of transition metal, increasing electron conductivity and lithium diffusion rate. As a result, electrochemical performances of the LMLO cathode are effectively enhanced. With optimization of the addition of KBH 4 , the electrode delivers a reversible capacity of 280 mAh g -1 at 0.1 C, which maintains after 100 cycles. The capacity retention with respect to the initial capacity is as high as 98% at 1 C after 400 cycles. The present work provides insights into designing a highly effective functional surface structure of LMLO cathode materials for high-performance LIBs., (© 2022 Wiley-VCH GmbH.)

Li- and Mn-rich layered oxides (LMROs) are considered the most promising cathode candidates for next-generation high-energy lithium-ion batteries. The poor cycling stability and fast voltage fading resulting from oxygen release during charging, however, severely hinders their practical application. Herein, a strategy of introducing an additional redox couple is proposed to eliminate the persistent problem of oxygen release. As a proof of concept, the cycling stability of Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 , which is a typical LMRO cathode, is substantially enhanced with the help of the S 2- /SO 3 2- redox couple, and the capacity shows no decay with a retention of 100% after 700 cycles at 1C, far superior to the bare counterpart (61.7%). The surface peroxide ions (O 2 2- ) are readily chemically reduced back to immobile O 2- by S 2- during charging, accompanied by the formation of SO 3 2- , which plays a critical role in stabilizing the oxygen lattice and eventually inhibiting the release of oxygen. More importantly, the S 2- ions are regenerated during the following discharging process and participate in the chemical redox reaction again. The findings shed light on a potential direction to tackle the poor cycling stability of high-energy anion-redox cathode materials for rechargeable metal-ion batteries., (© 2022 Wiley-VCH GmbH.)

Halide solid electrolytes have been considered as the most promising candidates for practical high-voltage all-solid-state lithium-ion batteries (ASSLIBs) due to their moderate ionic conductivity and good interfacial compatibility with oxide cathode materials. Aliovalent ion doping is an effective strategy to increase the ionic conductivity of halide electrolytes. However, the effects of ion doping on the electrochemical stability window of halide electrolytes and carbon additive on electrochemical performance are still unclear by far. Herein, a series of Zr-doped Li 3- x Er 1- x Zr x Cl 6 halide solid electrolytes (SEs) are synthesized through a mechanochemical method and the effects of Zr substitution on the ionic conductivity and electrochemical stability window are systematically investigated. Zr doping can increase the ionic conductivity, whereas it narrows the electrochemical stability window of the Li 3 ErCl 6 electrolyte simultaneously. The optimized Li 2.6 Er 0.6 Zr 0.4 Cl 6 electrolyte exhibits both a high ionic conductivity of 1.13 mS cm -1 and a high oxidation voltage of 4.21 V. Furthermore, carbon additives are demonstrated to be beneficial for achieving high discharge capacity and better cycling stability and rate performance for halide-based ASSLIBs, which are completely different from the case of sulfide electrolytes. ASSLIBs with uncoated LiCoO 2 cathode and carbon additives exhibit a high discharge capacity of 147.5 mAh g -1 and superior cycling stability with a capacity retention of 77% after 500 cycles. This work provides an in-depth understanding of the influence of ion doping and carbon additives on halide solid electrolytes and feasible strategies to realize high-energy-density ASSLIBs.

We present the development of a multi-resolution photoemission spectroscopy (MRPES) setup, which probes quantum materials in energy, momentum, space, and time. This versatile setup integrates three light sources in one photoemission setup and can conveniently switch between traditional angle-resolved photoemission spectroscopy (ARPES), time-resolved ARPES (trARPES), and micrometer-scale spatially resolved ARPES. It provides a first-time all-in-one solution to achieve an energy resolution of <4 meV, a time resolution of <35 fs, and a spatial resolution of ∼10 μm in photoemission spectroscopy. Remarkably, we obtain the shortest time resolution among the trARPES setups using solid-state nonlinear crystals for frequency upconversion. Furthermore, this MRPES setup is integrated with a shadow-mask assisted molecular beam epitaxy system, which transforms the traditional photoemission spectroscopy into a quantum device characterization instrument. We demonstrate the functionalities of this novel quantum material testbed using FeSe/SrTiO 3 thin films and MnBi 4 Te 7 magnetic topological insulators.

The downscaling of nonlinear optical devices is significantly hindered by the inherently weak nonlinearity in regular materials. Here, we report a giant third-harmonic generation discovered in epitaxial thin films of V-VI chalcogenide topological insulators. Using a tailored substrate and capping layer, a single reflection from a 13 nm film can produce a nonlinear conversion efficiency of nearly 0.01%, a performance that rivals micron-scale waveguides made from conventional materials or metasurfaces with far more complex structures. Such strong nonlinear optical emission, absent from the topologically trivial member in the same compound family, is found to be generated by the same bulk band characteristics that are responsible for producing the band inversion and the nontrivial topological ordering. This finding reveals the possibility of obtaining superior optical nonlinearity by examining the large pool of newly discovered topological materials with similar band characteristics.

Poor cyclic stability and low rate performance due to dramatic volume change and low intrinsic electronic conductivity are the two key issues needing to be urgently solved in silicon (Si)-based anodes for lithium-ion batteries. Herein, a novel tin (Sn)-bonded Si anode is proposed for the first time. Sn, which has a high electronic conductivity, is used to bond the Si-anode material and copper (Cu) current collector together using a hot-pressed method with a temperature slightly above the melting point of Sn. The cycling performance of the electrode is studied using a galvanostatic method. Nanoindentation and peeling tests are conducted to measure the mechanical strength of the electrodes. Direct current polarization and galvanostatic intermittent titration techniques are applied to assess the conductivity of the composites. Electrochemical impedance spectroscopy and X-ray photoelectron spectroscopy are conducted to evaluate the effect of the coating layer on the cycling ability of the composites. The Sn-bonded Si anodes show superior cycling stability and high rate performance with an improved initial Coulombic efficiency. Analyses reveal that the low-melting-point Sn helps to markedly improve the electronic conductivity of the electrodes and serves as a metallic binder as well to enhance the adhesive strength of the electrode. It is hopeful that this novel Sn-bonded Si anode provides a new insight for the development of advanced Si-based anodes for LIBs.

Poor cycling stability and rate capability are two key issues needing to be solved for Li- and Mn-rich oxide cathode material for lithium-ion batteries (LIBs). Herein, a novel perovskite electron-ion mixed conductor Nd 0.6 Sr 0.4 CoO 3 (NSCO) is used as the coating layer on Li 1.2 Ni 0.13 Co 0.13 Mn 0.54 O 2 (LNCMO) to simultaneously enhance its cycling stability and rate capability. By coating 3 wt% NSCO, LNCMO-3NSCO exhibits an optimal cycling performance with a capacity retention of 99% at 0.1C (1C = 200 mA g -1 ) after 60 cycles, 91% at 1C after 300 cycles, and 54% at 20C after 1000 cycles, much better than 78%, 63%, and 3% of LNCMO, respectively. Even at a high charge and discharge rate of 50C, LNCMO-3NSCO exhibits a discharge capacity of 53 mAh g -1 and a mid-point discharge voltage of 2.88 V, much higher than those of LNCMO (24 mA h g -1 and 2.40 V, respectively). Benefiting from the high electronic conductivity (1.46 S cm -1 ) and ionic conductivity (1.48 × 10 -7  S cm -1 ), NSCO coating not only suppresses transition metals dissolution and structure transformation, but also significantly enhances electronic conductivity and Li + diffusion coefficient of LNCMO by an order of magnitude., (© 2021 Wiley-VCH GmbH.)

How superconductivity emerges from antiferromagnetic ordering is an essential question for Fe-based superconductors. Here, we explore the effect of dimensionality on the interplay between antiferromagnetic ordering and superconductivity by investigating nanoribbons of single-layer FeTe 1- x Se x films grown on SrTiO 3 (001) substrates by molecular beam epitaxy. Using scanning tunneling microscopy/spectroscopy, we find a one-dimensional (1D) superconducting channel 2 nm wide with a T C of 42 ± 4 K on the edge of FeTe 1- x Se x ( x < 0.1) ribbons, coexisting with a non-superconducting ribbon interior that remains bicollinear antiferromagnetically ordered. Density functional theory calculations indicate that both Se and the presence of the edge destabilize the bicollinear antiferromagnetic magnetic order, resulting in a paramagnetic region near the edge with strong local checkerboard fluctuations that is conducive to superconductivity. Our results represent the highest T C achieved in 1D superconductors and demonstrate an effective route toward stabilizing superconductivity in Fe-based superconductors at reduced dimensions.

We report the magneotransport studies on the topological crystalline insulator (TCI) Pb 1-x Sn x Te (111) single crystal thin films grown by molecular beam epitaxy. By decreasing Sn content, an enhanced sheet resistance and decreased hole density are observed in Pb 1-x Sn x Te (111) thin films. A weak antilocalization likely related to the topological surface states is observed in transport of Pb 1-x Sn x Te (x > 0.4) thin films, whereas a weak localization is displayed in Pb 1-x Sn x Te (x < 0.4) thin films. This tunable weak antilocalization to weak localization transition is attributed to the open of Dirac gap because of the topological phase transition in TCI Pb 1-x Sn x Te. Our research has a potential application in the tunable electronic and spintronic devices and is very significant to the fundamental research based on TCI Pb 1-x Sn x Te thin film.

The de Gennes extrapolation length is a direction dependent measure of the spatial evolution of the pairing gap near the boundary of a superconductor and thus provides a viable means to probe its symmetry. It is expected to be infinite and isotropic for plain s-wave pairing, and finite and anisotropic for d-wave. Here, we synthesize single-layer FeSe films on SrTiO 3 (001) (STO) substrates by molecular beam epitaxy and measure the de Gennes extrapolation length by scanning tunneling microscopy/spectroscopy. We find a 40% reduction of the superconducting gap near specular [110] Fe edges, yielding an extrapolation length of 8.0 nm. However, near specular [010] Fe edges, the extrapolation length is nearly infinite. These findings are consistent with a phase changing pairing with 2-fold symmetry, indicating d-wave superconductivity. This is further supported by the presence of in-gap states near the specular [110] Fe edges, but not the [010] Fe edges. This work provides direct experimental evidence for d-wave superconductivity in single-layer FeSe/STO and demonstrates quasiparticle scattering at boundaries to be a viable phase sensitive probe of pairing symmetry in Fe-based superconductors.

The capability of controlling superconductivity by light is highly desirable for active quantum device applications. Since superconductors rarely exhibit strong photoresponses, and optically sensitive materials are often not superconducting, efficient coupling between these two characters can be very challenging in a single material. Here we show that, in FeSe/SrTiO 3 heterostructures, the superconducting transition temperature in FeSe monolayer can be effectively raised by the interband photoexcitations in the SrTiO 3 substrate. Attributed to a light induced metastable polar distortion uniquely enabled by the FeSe/SrTiO 3 interface, this effect only requires a less than 50 µW cm -2 continuous-wave light field. The fast optical generation of superconducting zero resistance state is non-volatile but can be rapidly reversed by applying voltage pulses to the back of SrTiO 3 substrate. The capability of switching FeSe repeatedly and reliably between normal and superconducting states demonstrate the great potential of making energy-efficient quantum optoelectronics at designed correlated interfaces.

Grain boundaries (GBs) are inherent extended defects in chemical vapor deposited (CVD) transition metal dichalcogenide (TMD) films. Characterization of the atomic structure and electronic properties of these GBs is crucial for understanding and controlling the properties of TMDs via defect engineering. Here, we report the atomic and electronic structure of GBs in CVD grown MoS 2 on epitaxial graphene/SiC(0001). Using scanning tunneling microscopy/spectroscopy, we find that GBs mostly consist of arrays of dislocation cores, where the presence of mid-gap states shifts both conduction and valence band edges by up to 1 eV. Our findings demonstrate the first charging effect near GBs in CVD grown MoS 2 , providing insights into the significant impact GBs can have on materials properties.

The surface of a topological crystalline insulator (TCI) carries an even number of Dirac cones protected by crystalline symmetry. We epitaxially grew high-quality Pb(1-x)Sn(x)Te(111) films and investigated the TCI phase by in situ angle-resolved photoemission spectroscopy. Pb(1-x)Sn(x)Te(111) films undergo a topological phase transition from a trivial insulator to TCI via increasing the Sn/Pb ratio, accompanied by a crossover from n-type to p-type doping. In addition, a hybridization gap is opened in the surface states when the thickness of the film is reduced to the two-dimensional limit. The work demonstrates an approach to manipulating the topological properties of TCI, which is of importance for future fundamental research and applications based on TCI.

Myocardial ischemic disorders are the leading causes of mortality worldwide, and current therapies only delay progression of these diseases. Traditional stem cell therapies face various impediments, including the typical ethical and immunological problems in clinical application. Recently, induced pluripotent stem (iPS) cells have been shown to offer a novel fascinating route to patient-specific and disease-specific pluripotent cells, without the technical and ethical limitations of somatic cell nuclear transfer method. However, iPS cells' limited viability after transplantation in infarcted microenvironment, and low rate of differentiation into cardiovascular tissues restricts their regenerative capacity. Genetically modified iPS cells with the recently discovered cellular repressor of E1A-stimulated genes (CREG), which inhibits apoptosis and inflammation but enhances differentiation, may resolve these crucial problems. Possible mechanisms may include CREG promotion of angiogenesis by VEGF, suppression of inflammation and resistance of apoptosis via activating PI3K/Akt and blocking p38 MARK signaling, and maintenance of endothelial differentiation conditions. The exact mechanisms that CREG can modulate iPS cells' survival and differentiation remain to be investigated., (Copyright © 2010. Published by Elsevier Ltd.)

Bone marrow-derived mesenchymal stem cells (MSCs) have great potential for repair after myocardial infarction. However, poor viability of transplanted MSCs in the ischemic heart has limited their therapeutic potential. Cellular repressor of E1A-stimulated genes (CREG) has been identified as a potent inhibitor of apoptosis. The aim of this study was to investigate the anti-apoptotic effects of CREG on MSCs under hypoxic and serum deprivation (SD) conditions. We also investigated the potential mechanism(s) that may mediate the actions of CREG. All experiments were performed on rat bone marrow MSCs. Apoptosis was induced by exposure of cells to hypoxia/SD in a sealed GENbox hypoxic chamber. Effects of CREG were investigated in the absence or presence of inhibitors that target phosphoinositide 3-kinase (PI3K). We found that the overexpression of CREG markedly protected MSCs from hypoxia/SD-induced apoptosis through inhibition of the mitochondrial apoptotic pathway, leading to attenuation of caspase-3. Moreover, CREG enhanced Akt phosphorylation and decreased the expression of p53 in MSCs under hypoxic/SD conditions. The PI3K/Akt inhibitor LY294002 significantly increased the amount of p53 protein and attenuated the anti-apoptotic effects of CREG on MSCs. This study indicates that CREG is a novel and potent survival factor for MSCs, therefore, it may be a useful therapeutic adjunct for transplanting MSCs into damaged heart after myocardial infarction.