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1.
Small ; : e2308858, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38618927

RESUMO

Although TiNb2O7 (TNO) with comparable operating potential and ideal theoretical capacity is considered to be the most ideal replacement for negative Li4Ti5O12 (LTO), the low ionic and electronic conductivity still limit its practical application as satisfactory anode for lithium-ion batteries (LIBs) with high-power density. Herein, TNO nanoparticles modified by Cerium (Ce) with outstanding electrochemical performance are synthesized. The successful introduction of Ce3+ in the lattice leads to increased interplanar spacing, refined grain size, more oxygen vacancy, and a smaller lithium diffusion barrier, which are conducive to improve conductivity of both Li+ and electrons. As a result, the modified TNO reaches high reversible capacity of 256.0 mA h g-1 at 100 mA g-1 after 100 cycles, and 183.0 mA h g-1 even under 3200 mA g-1. In particular, when the temperature drops to -20 °C, the cell undergoing 1500 cycles at a high current density of 500 mA g-1 can still reach 89.7 mA h g-1, corresponding to a capacity decay rate per cycle of only 0.033%. This work provides a new way to improve the electrochemical properties of alternative anodes for LIBs at extreme temperature.

2.
Transplant Rev (Orlando) ; 38(2): 100841, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38518424

RESUMO

Rat orthotopic liver transplantation (ROLT) serves as an ideal animal model and has gained popularity in addressing complications and perioperative treatments related to clinical liver transplantation. Through extensive research on ROLT model construction, the conventional "two-cuff" method has gradually become established. However, traditional methods still present challenges including limited visual field during vascular suturing, vascular torsion, biliary tract injuries, and prolonged anhepatic periods. Consequently, this paper aims to review the latest advancements and various techniques in this field, providing a valuable reference for individuals interested in constructing ROLT models.


Assuntos
Transplante de Fígado , Humanos , Ratos , Animais , Transplante de Fígado/métodos , Modelos Animais , Anastomose Cirúrgica
3.
Phys Rev Lett ; 132(5): 056301, 2024 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-38364160

RESUMO

Recent experiments reported an antisymmetric planar Hall effect, where the Hall current is odd in the in plane magnetic field and scales linearly with both electric and magnetic fields applied. Existing theories rely exclusively on a spin origin, which requires spin-orbit coupling to take effect. Here, we develop a general theory for the intrinsic planar Hall effect (IPHE), highlighting a previously unknown orbital mechanism and connecting it to a band geometric quantity-the anomalous orbital polarizability (AOP). Importantly, the orbital mechanism does not request spin-orbit coupling, so sizable IPHE can occur and is dominated by an orbital contribution in systems with weak spin-orbit coupling. Combined with first-principles calculations, we demonstrate our theory with quantitative evaluation for bulk materials TaSb_{2}, NbAs_{2}, and SrAs_{3}. We further show that AOP and its associated orbital IPHE can be greatly enhanced at topological band crossings, offering a new way to probe topological materials.

4.
Small ; 20(9): e2304147, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37875665

RESUMO

Room-temperature gallium-based liquid metals (RT-GaLMs) have garnered significant interest recently owing to their extraordinary combination of fluidity, conductivity, stretchability, self-healing performance, and biocompatibility. They are ideal materials for the manufacture of flexible electronics. By changing the composition and oxidation of RT-GaLMs, physicochemical characteristics of the liquid metal can be adjusted, especially the regulation of rheological, wetting, and adhesion properties. This review highlights the advancements in the liquid metals used in flexible electronics. Meanwhile related characteristics of RT-GaLMs and underlying principles governing their processing and applications for flexible electronics are elucidated. Finally, the diverse applications of RT-GaLMs in self-healing circuits, flexible sensors, energy harvesting devices, and epidermal electronics, are explored. Additionally, the challenges hindering the progress of RT-GaLMs are discussed, while proposing future research directions and potential applications in this emerging field. By presenting a concise and critical analysis, this paper contributes to the advancement of RT-GaLMs as an advanced material applicable for the new generation of flexible electronics.

5.
Nano Lett ; 23(23): 11266-11271, 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-37976102

RESUMO

As an ideal platform, both the theoretical prediction and first experimental verification of chiral phonons are based on transition-metal dichalcogenide materials. The manipulation of phonon chirality in these materials will have a profound effect on the study of chiral phonons. In this work, we utilize the sliding ferroelectric effect to realize the phonon chirality manipulation mechanism in transition-metal dichalcogenide materials. Based on first-principles calculations, we find the different manipulation effects of interlayer sliding on the phonon chirality and Berry curvature in bilayer and four-layer MoS2 sliding ferroelectrics. These further affect the phonon angular momentum and magnetization under a temperature gradient and the phonon Hall effect under a magnetic field. Our work connects two emerging fields and opens up a new route to manipulating phonon chirality in transition-metal dichalcogenide materials through the sliding ferroelectric mechanism.

6.
Nano Lett ; 23(16): 7358-7363, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37535707

RESUMO

Real Chern insulators have attracted great interest, but so far, their material realization is limited to nonmagnetic crystals and systems without spin-orbit coupling. Here, we reveal the magnetic real Chern insulator (MRCI) state in a recently synthesized metal-organic framework material Co3(HITP)2. Its ground state with in-plane ferromagnetic ordering hosts a nontrivial real Chern number, enabled by the C2zT symmetry and robustness against spin-orbit coupling. Distinct from previous nonmagnetic examples, the topological corner zero modes of MRCIs are spin-polarized. Furthermore, under small tensile strains, the material undergoes a topological phase transition from the MRCI to a magnetic double-Weyl semimetal phase, via a pseudospin-1 critical state. Similar physics can also be found in closely related materials Mn3(HITP)2 and Fe3(HITP)2, which also exist. Possible experimental detections and implications of an emerging magnetic flat band in the system are discussed.

7.
Phys Rev Lett ; 130(16): 166302, 2023 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-37154629

RESUMO

We propose a time-reversal-even spin generation in second order of electric fields, which dominates the current induced spin polarization in a wide class of centrosymmetric nonmagnetic materials, and leads to a novel nonlinear spin-orbit torque in magnets. We reveal a quantum origin of this effect from the momentum space dipole of the anomalous spin polarizability. First-principles calculations predict sizable spin generations in several nonmagnetic hcp metals, in monolayer TiTe_{2}, and in ferromagnetic monolayer MnSe_{2}, which can be detected in experiment. Our work opens up the broad vista of nonlinear spintronics in both nonmagnetic and magnetic systems.

8.
Inorg Chem ; 62(1): 381-391, 2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36576868

RESUMO

Two different 1,3-functionalized indolyl-based proligands 1-(2-C4H7O)CH2-3-(2-tBuC6H5N═CH)C8H5N (HL1) and 1-Me2NCH2CH2-3-(2-iPrC6H5N═CH)C8H5N (HL2) were designed, prepared in high yields, and successfully applied to rare-earth metal chemistry showing different reactivities and different bondings with the central metals. The reactions of HL1 with RE(CH2SiMe3)3(THF)2 provided two types of rare-earth metal complexes: the pincer type mononuclear complexes κ3-(L1)RE(CH2SiMe3)2 [L1 = 1-(2-C4H7O)CH2-3-(2-tBuC6H5N═CH)C8H4N, RE = Lu(1), Yb(2)], and the dinuclear rare-earth metal alkyl (per alkyl/per metal) complexes having the ligand in novel coordination modes {(η1:(µ-η2:η1):η1-1-(2-C4H7O)CH2-3-[2-tBuC6H5NCH-(CH2SiMe3)]C8H4N)RECH2SiMe3}2 [RE = Er(3), Y(4), Dy(5), and Gd(6)]. Meanwhile, the reactions of HL2 with RE(CH2SiMe3)3(THF)2 led to the isolation and characterization of only the mononuclear rare-earth metal dialkyl complexes κ3-(L2)RE(CH2SiMe3)2 [L2 = 1-Me2NCH2CH2-3-(2-iPrC6H5N═CH)C8H4N, RE = Lu(7), Gd(8)] bearing the ligand in the pincer chelate form. The mononuclear complexes were formed through the sp2 C-H activation of the 2-indolyl moiety, while the dinuclear complexes were produced unexpectedly through the tandem 2-indolyl sp2 C-H activation and C═N insertion into the RE-CH2SiMe3 bond. These complexes were fully characterized by spectroscopic methods, elemental analyses, and single-crystal X-ray crystallography. The applications of the synthesized complexes as catalysts for the hydrosilylation of terminal alkenes with phenylsilane are described. Anti-Markovnikov addition products were produced by the hydrosilylation of aliphatic olefins, and Markovnikov addition products were isolated with aromatic olefins with high selectivity in the absence of cocatalysts. It is found that the dinuclear rare-earth alkyl complexes exhibited the best catalytic activity with the advantages of mild reaction conditions, short reaction time, low catalyst loading, and wide substrate applicability in comparison with the synthesized mononuclear complexes and the reported catalysts.

9.
Front Oncol ; 13: 1174999, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38162488

RESUMO

Objective: To assess the efficacy and safety of camrelizumab plus different targeted drugs in adjuvant therapy after hepatocellular carcinoma (HCC) surgery. Patients and methods: This retrospective cohort study included HCC patients who, after undergoing failed postoperative adjuvant lenvatinib therapy, received intravenous camrelizumab 200 mg every 3 weeks (C group, n = 97), camrelizumab plus oral apatinib 250 mg daily (C+A group, n = 125), camrelizumab plus oral lenvatinib 12 mg daily (for bodyweight ≥60 kg)/lenvatinib 8 mg daily (for bodyweight <60 kg) (C+L group, n = 120), or camrelizumab plus oral sorafenib 400 mg bi-daily (C+S group, n = 114) between October 2020 and October 2021. The outcomes including the objective response rate (ORR) and disease control rate (DCR) were evaluated by RECIST 1.1 and iRECIST. The median progression-free survival (mPFS), median overall survival (mOS), 6-month OS rate, 12-month OS rate, and adverse events were evaluated. Results: As of 31 May 2022 with last follow-up time, the ORR was 17.2% for the C group, 44.6% for the C+A group, 47.9% for the C+L group, and 36.3% for the C+S group. The DCR was 72.0% for the C group, 81.8% for the C+A group, 85.5% for the C+L group, and 77.9% for the C+S group. The mPFS was 11.0 months (10.1-12.8) for the C group, 14.0 months (12.7-16.5) for the C+A group, 18.0 months (16.9-20.1) for the C+L group, and 12.0 months (9.7-14.4) for the C+S group. The mOS was 13.0 months (11.6-15.3) for the C group, 17.0 months (15.8-19.4) for the C+A group, 19.0 months (17.7-20.2) for the C+L group, and 15.0 months (14.1-17.3) for the C+S group. Grade 3 or 4 treatment-related adverse events occurred in 14 patients (14.4%) for the C group, 10 patients (8.0%) for the C+A group, 5 patients (4.2%) for the C+L group, and 11 patients (9.6%) for the C+S group. The most common adverse events were fatigue and transaminitis. Conclusion: Camrelizumab combined with lenvatinib as adjuvant therapy showed promising efficacy and manageable safety in HCC patients. It might be a potential adjuvant therapy or second-line treatment for these patients.

10.
Biomolecules ; 12(12)2022 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-36551229

RESUMO

Interleukin-18 (IL-18) can effectively activate natural killer (NK) cells and induce large concentrations of interferon-γ (IFN-γ). In healthy humans, IL-18 binding protein (IL-18BP) can inhibit the binding of IL-18 to IL-18R and counteract the biological action of IL-18 due to its high concentration and high affinity, thus preventing the production of IFN-γ and inhibiting NK-cell activation. Through previous studies and the phenomena observed by our group in pig-non-human primates (NHPs) liver transplantation experiments, we proposed that the imbalance in IL-18/IL-18BP expression upon transplantation encourages the activation, proliferation, and cytotoxic effects of NK cells, ultimately causing acute vascular rejection of the graft. In this research, we used Lewis-Brown Norway rat orthotopic liver transplantation (OLTx) as a model of acute vascular rejection. AAV8-Il18bp viral vectors as gene delivery vehicles were constructed for gene therapy to overexpress IL-18BP and alleviate NK-cell rejection of the graft after transplantation. The results showed that livers overexpressing IL-18BP had reduced damage and could function longer after transplantation, effectively improving the survival time of the recipients.


Assuntos
Vasos Sanguíneos , Terapia Genética , Rejeição de Enxerto , Sobrevivência de Enxerto , Interleucina-18 , Transplante de Fígado , Animais , Ratos , Rejeição de Enxerto/prevenção & controle , Interferon gama/genética , Interferon gama/metabolismo , Interleucina-18/genética , Interleucina-18/metabolismo , Transplante de Fígado/métodos , Ratos Endogâmicos Lew , Sobrevivência de Enxerto/genética , Vasos Sanguíneos/imunologia , Vetores Genéticos
11.
Sci Bull (Beijing) ; 67(4): 375-380, 2022 Feb 26.
Artigo em Inglês | MEDLINE | ID: mdl-36546089

RESUMO

The past decade has witnessed a surge of interest in exploring emergent particles in condensed matter systems. Novel particles, emerged as excitations around exotic band degeneracy points, continue to be reported in real materials and artificially engineered systems, but so far, we do not have a complete picture on all possible types of particles that can be achieved. Here, via systematic symmetry analysis and modeling, we accomplish a complete list of all possible particles in time-reversal-invariant systems. This includes both spinful particles such as electron quasiparticles in solids, and spinless particles such as phonons or even excitations in electric-circuit and mechanical networks. We establish detailed correspondence between the particle, the symmetry condition, the effective model, and the topological character. This obtained encyclopedia concludes the search for novel emergent particles and provides concrete guidance to achieve them in physical systems.

12.
Dalton Trans ; 51(46): 17795-17803, 2022 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-36349905

RESUMO

Novel tetranuclear organocopper(I) clusters bridged by two halides and two indolyl-based NCN pincer ligands were synthesized through the reactions of Cu(I) halides with lithiated ligands. Single-crystal X-ray diffraction revealed that the structure of these complexes included a [Cu4X2]2+ cluster unit wherein the four copper ions were stabilized by multiple Cu-Cu interactions, arranged in a distorted tetrahedral fashion and the halide anions µ3-bridged with metal centers. Meanwhile, these clusters displayed excellent catalytic activities towards the hydrophosphination of alkenes under solvent-free conditions with wide functional group tolerance.

13.
Front Public Health ; 10: 1037508, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36388269

RESUMO

Background and aim: Chronic hepatitis B (CHB) can be divided into immune tolerance (IT), immune clearance (IC), hepatitis B e antigen (HBeAg)-negative inactive/quiescent carrier (ENQ), and HBeAg-negative hepatitis (ENH) phases. The conventional biomarkers used to distinguish these phases have limitations. We examined the clinical significance of hepatitis B virus (HBV) RNA and hepatitis B core-related antigen (HBcrAg) as novel biomarkers. Methods: One hundred eighty-nine patients without treatment currently were categorized by CHB phase (IT = 46, IC = 45, ENQ = 49, ENH = 49). The associations of HBV RNA and HBcrAg with HBV DNA and alanine transaminase (ALT) were analyzed. The decision tree model was used to distinguish the four phases in the natural course of CHB. Results: The concentrations of HBV RNA and HBcrAg were highest in the IT and IC phases (P < 0.01). Serum HBV RNA was similar to HBcrAg in treatment-naïve patients. HBV RNA and HBcrAg correlated with HBV DNA in the HBeAg+ and HBeAg- status (HBV RNA: e+ r = 0.51, e- r = 0.62; HBcrAg: e+ r = 0.51, e- r = 0.71), but their association with HBV DNA differed among phases. The accuracy, sensitivity, and specificity of HBcrAg with ALT in distinguishing the CHB phases were 95.65%, 95.83%, and 95.55%, respectively. Conclusion: Serum HBV RNA and HBcrAg may be useful to monitor CHB progression.


Assuntos
Hepatite B Crônica , Hepatite B , Humanos , Antígenos E da Hepatite B/uso terapêutico , Hepatite B Crônica/diagnóstico , Hepatite B Crônica/tratamento farmacológico , DNA Viral/uso terapêutico , Antígenos do Núcleo do Vírus da Hepatite B/uso terapêutico , Biomarcadores , RNA/uso terapêutico
14.
Phys Chem Chem Phys ; 24(41): 25287-25297, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36226481

RESUMO

Direct Z-scheme water-splitting is a promising route to enhancing the photocatalytic performance due to the effective separation of photogenerated carriers while simultaneously preserving the strong oxidation activity of holes and reduction activity of electrons. In this work, the MoSSe/XY2 (X = Hf, Zr; S, Se) heterostructures (HSs) with different contacts are proposed for Z-scheme photocatalytic water-spitting by first principles calculation. The separation of photogenerated carriers for HfSe2/SMoSe and ZrSe2/SMoSe HSs is limited by the type-I band alignment, while the hydrogen production ability of HfSe2/SeMoS and ZrSe2/SeMoS HSs is limited by the lower conduction band edge positions relative to the water reduction potential. The HfS2/SMoSe, HfS2/SeMoS, ZrS2/SMoSe, and ZrS2/SeMoS HSs are direct Z-scheme water-splitting photocatalysts with the oxygen evolution reaction (OER) and hydrogen evolution reaction (HER) occurring at the Hf(Zr)S2 layer and MoSSe layer, respectively. More excitingly, the S (or Se) vacancies effectively lower the HER overpotentials. Besides, the solar-to-hydrogen efficiencies are 6.1%, 5.9%, 6.4%, and 6.3% for HfS2/SMoSe, HfS2/SeMoS, ZrS2/SMoSe, and ZrS2/SeMoS HSs, respectively. This work paves the way for designing highly efficient overall water-splitting photocatalysts using 2D materials.

15.
Phys Rev Lett ; 129(8): 086602, 2022 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-36053706

RESUMO

We propose an intrinsic nonlinear electric spin generation effect, which can dominate in centrosymmetric magnets. We reveal the band geometric origin of this effect and clarify its symmetry characters. As an intrinsic effect, it is determined solely by the material's band structure and represents a material characteristic. Combining our theory with first-principle calculations, we predict sizable nonlinear spin generation in single-layer MnBi_{2}Te_{4}, which can be detected in experiment. Our theory opens a new route for all-electric controlled spintronics in centrosymmetric magnets which reside outside of the current paradigm based on linear spin response.

16.
Nanoscale ; 14(34): 12491-12497, 2022 Sep 02.
Artigo em Inglês | MEDLINE | ID: mdl-35983780

RESUMO

Topological and ferromagnetic features in two-dimensional (2D) materials have attracted considerable interest due to their excellent physical properties. 2D Weyl half-semimetals (WHSMs) are excellent platforms to study both properties. In this study, we predicted a 2D ferromagnetic WHSM, VB28, via first-principles calculations. The VB28 monolayer displays ultra-high thermodynamic stability. It has a couple of fully spin-polarized Weyl nodal points in the spin-down channel. The Weyl points are found to be protected by vertical mirror and antiunitary C2zT symmetries, which are robust against spin-orbit coupling (SOC) and in-plane strains. Our study not only discovers an intrinsic ferromagnetic 2D WSHM material with Weyl points around the Fermi level but also provides a potential candidate with good stability for spintronic devices.

18.
J Phys Condens Matter ; 34(25)2022 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-35381579

RESUMO

By combining tight-binding modelling with density functional theory based first-principles calculations, we investigate the band evolution of two-dimensional (2D) hexagonal lattices with (px,py) orbitals, focusing on the electronic structures and topological phase transitions. The (px,py)-orbital hexagonal lattice model possesses two flat bands encompassing two linearly dispersive Dirac bands. Breaking the A/B sublattice symmetry could transform the model into two triangular lattices, each featuring a flat band and a dispersive band. Inclusion of the spin-orbit coupling and magnetization may give rise to quantum spin Hall and quantum anomalous Hall (QAH) states. As a proof of concept, we demonstrate that half-hydrogenated stanene is encoded by a triangular lattice with (px,py) orbitals, which exhibits ferromagnetism and QAH effect with a topological gap of ∼0.15 eV, feasible for experimental observation. These results provide insights into the structure-property relationships involving the orbital degree of freedom, which may shed light on future design and preparation of 2D topological materials for novel electronic/spintronic and quantum computing devices.

19.
Adv Mater ; 34(21): e2107520, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35261089

RESUMO

Combining magnetism and nontrivial band topology gives rise to quantum anomalous Hall (QAH) insulators and exotic quantum phases such as the QAH effect where current flows without dissipation along quantized edge states. Inducing magnetic order in topological insulators via proximity to a magnetic material offers a promising pathway toward achieving the QAH effect at a high temperature for lossless transport applications. One promising architecture involves a sandwich structure comprising two single-septuple layers (1SL) of MnBi2 Te4 (a 2D ferromagnetic insulator) with ultrathin few quintuple layer (QL) Bi2 Te3 in the middle, and it is predicted to yield a robust QAH insulator phase with a large bandgap greater than 50 meV. Here, the growth of a 1SL MnBi2 Te4 /4QL Bi2 Te3 /1SL MnBi2 Te4 heterostructure via molecular beam epitaxy is demonstrated and the electronic structure probed using angle-resolved photoelectron spectroscopy. Strong hexagonally warped massive Dirac fermions and a bandgap of 75 ± 15 meV are observed. The magnetic origin of the gap is confirmed by the observation of the exchange-Rashba effect, as well as the vanishing bandgap above the Curie temperature, in agreement with density functional theory calculations. These findings provide insights into magnetic proximity effects in topological insulators and reveal a promising platform for realizing the QAH effect at elevated temperatures.

20.
Nano Lett ; 22(4): 1688-1693, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35148114

RESUMO

The diode effect means that carriers can only flow in one direction but not the other. While diode effects for electron charge, spin, or photon have been widely discussed, it remains a question whether a chiral phonon diode can be realized, which utilizes the chiral degree of freedom of lattice vibrations. In this work, we reveal an intrinsic connection between the chiralities of a crystal structure and its phonon excitations, which naturally leads to the chiral phonon diode effect in chiral crystals. At a certain frequency, phonons with a definite chirality can propagate only in one direction but not the opposite. We demonstrate the idea in concrete materials including bulk Te and α-quartz (SiO2). Our work discovers the fundamental physics of chirality coupling between different levels of a system, and the predicted effect will provide a new route to control phonon transport and design information devices.

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