Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 562
Filtrar
1.
Ther Drug Monit ; 2024 Sep 06.
Artículo en Inglés | MEDLINE | ID: mdl-39240829

RESUMEN

BACKGROUND: Pyrazinamide is used to treat drug-susceptible (DS) and multidrug-resistant (MDR) tuberculosis (TB). This study aimed to characterize the factors associated with the pharmacokinetic parameters of pyrazinamide and evaluate the disposition of the current regimen, which could provide suggestions for adequate dosing strategies for therapeutic targets. METHODS: A population pharmacokinetic model of pyrazinamide was developed based on the data from 499 plasma concentrations from 222 Chinese patients diagnosed with DS or MDR TB. Pyrazinamide exposure was best described using a one-compartment model. RESULTS: No significant differences were observed in the pharmacokinetic parameters between DS and MDR TB. The final covariate model showed that total body weight was the only significant covariate for apparent clearance, which increased by 0.45 L/h with a 10 kg increase in body weight. A simulation showed that for typical subjects weighing 40-80 kg, a fixed dosage of 1500 mg daily had an area under the concentration-time curve from 0 to 24 hours (AUC0-24) of 389.9-716.0 mg·h/L and peak serum concentrations of the drug (Cmax) of 32.2-44.8 mg/L. CONCLUSIONS: Fixed pyrazinamide doses of 1500, 1750, and 2000 mg are recommended for patients weighing 40-70, 70-80, and 80-90 kg, respectively, to achieve the exposure targets of AUC0-24 > 363 mg·h/L or Cmax > 35 mg/L to attain efficacy.

2.
Nature ; 633(8028): 71-76, 2024 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-39198651

RESUMEN

Majorana zero modes (MZMs) are emergent zero-energy topological quasiparticles that are their own antiparticles1,2. Detected MZMs are spatially separated and electrically neutral, so producing hybridization between MZMs is extremely challenging in superconductors3,4. Here, we report the magnetic field response of vortex bound states in superconducting topological crystalline insulator SnTe (001) films. Several MZMs were predicted to coexist in a single vortex due to magnetic mirror symmetry. Using a scanning tunnelling microscope equipped with a three-axis vector magnet, we found that the zero-bias peak (ZBP) in a single vortex exhibits an apparent anisotropic response even though the magnetic field is weak. The ZBP can robustly extend a long distance of up to approximately 100 nm at the (001) surface when the magnetic field is parallel to the ( 1 1 ¯ 0 )-type mirror plane, otherwise it displays an asymmetric splitting. Our systematic simulations demonstrate that the anisotropic response cannot be reproduced with trivial ZBPs. Although the different MZMs cannot be directly distinguished due to the limited energy resolution in our experiments, our comparisons between experimental measurements and theoretical simulations strongly support the existence and hybridization of symmetry-protected multiple MZMs. Our work demonstrates a way to hybridize different MZMs by controlling the orientation of the magnetic field and expands the types of MZM available for tuning topological states.

3.
Front Microbiol ; 15: 1420899, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39135873

RESUMEN

The Yongle blue hole (YBH), situated in the South China Sea, represents a compelling subject of study in marine microbiology due to its unique redox-layered microbial ecosystems. However, the diversity and ecology of microbial eukaryotes within the YBH remains underexplored. This study endeavors to bridge this gap through the application of the in situ microbial filtration and fixation (ISMIFF) device to collect 0.22-30 µm microbial samples from 21 water layers of YBH. Subsequent extraction of 18S rRNA metagenomic reads of 21 metagenomes and 10 metatranscriptomes facilitated a comprehensive analysis of community structures. Findings revealed a pronounced superiority in the diversity and richness of eukaryotic microorganisms in the oxic zone compared to its suboxic and anoxic counterparts. Notably, Dinophyceae and Maxillopoda emerged as the predominant taxa based on the analysis of the 18S rRNA reads for the V4 and V9 regions, which showed stratification In their relative abundance and suggested their potential role in the thermo-halocline boundaries and oxic-anoxic interface. Specifically, In these eukaryotic microbial communities, Dinophyceae exhibited significant abundance at 20 m (20.01%) and 105 m (26.13%) water depths, while Maxillopoda was prevalent at 40 m (22.84%), 80 m (23.19%), and 100 m (15.42%) depths. A part of these organisms, identified as larvae and protists, were likely attracted by swarming chemosynthetic bacterial prey prevailing at the thermo-halocline boundaries and oxic-anoxic interface. Furthermore, the phylogenetic relationships of the major 18S operational taxonomic units (OTUs) showed a close adjacency to known species, except for three Dinophyceae OTUs. In conclusion, this study provides critical insights into the vertical distribution and transcriptional activity of <30-µm eukaryotic microbes, shedding light on the taxonomic novelty of eukaryotic microorganisms within the semi-enclosed blue holes.

4.
Front Mol Biosci ; 11: 1436135, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-39193220

RESUMEN

Introduction: Individuals with diabetes mellitus (DM) are at an increased risk of Mycobacterium tuberculosis (Mtb) infection and progressing from latent tuberculosis (TB) infection to active tuberculosis disease. TB in the DM population is more likely to go undiagnosed due to smear-negative results. Methods: Exhaled breath samples were collected and analyzed using high-pressure photon ionization time-of-flight mass spectrometry. An eXtreme Gradient Boosting (XGBoost) model was utilized for breathomics analysis and TB detection. Results: XGBoost model achieved a sensitivity of 88.5%, specificity of 100%, accuracy of 90.2%, and an area under the curve (AUC) of 98.8%. The most significant feature across the entire set was m106, which demonstrated a sensitivity of 93%, specificity of 100%, and an AUC of 99.7%. Discussion: The breathomics-based TB detection method utilizing m106 exhibited high sensitivity and specificity potentially beneficial for clinical TB screening and diagnosis in individuals with diabetes.

5.
Phys Rev Lett ; 133(6): 066601, 2024 Aug 09.
Artículo en Inglés | MEDLINE | ID: mdl-39178450

RESUMEN

We predict the emergence of a state of matter with intertwined ferromagnetism, charge order, and topology in fractionally filled moiré superlattice bands. Remarkably, these quantum anomalous Hall crystals exhibit a quantized integer Hall conductance that is different than expected from the filling and Chern number of the band. Microscopic calculations show that this phase is robustly favored at half-filling (ν=1/2) at larger twist angles of the twisted semiconductor bilayer tMoTe_{2}.

6.
Science ; 385(6704): 86-91, 2024 Jul 05.
Artículo en Inglés | MEDLINE | ID: mdl-38963852

RESUMEN

Semiconductor moiré superlattices provide a versatile platform to engineer quantum solids composed of artificial atoms on moiré sites. Previous studies have mostly focused on the simplest correlated quantum solid-the Fermi-Hubbard model-in which intra-atom interactions are simplified to a single onsite repulsion energy U. Here we report the experimental observation of Wigner molecular crystals emerging from multielectron artificial atoms in twisted bilayer tungsten disulfide moiré superlattices. Using scanning tunneling microscopy, we demonstrate that Wigner molecules appear in multielectron artificial atoms when Coulomb interactions dominate. The array of Wigner molecules observed in a moiré superlattice comprises a crystalline phase of electrons: the Wigner molecular crystal, which is shown to be highly tunable through mechanical strain, moiré period, and carrier charge type.

7.
Phys Rev Lett ; 132(24): 246402, 2024 Jun 14.
Artículo en Inglés | MEDLINE | ID: mdl-38949360

RESUMEN

Moiré materials provide a highly tunable platform in which novel electronic phenomena can emerge. We study strained moiré materials in a uniform magnetic field and predict highly anisotropic electrical conductivity that switches easy axis as magnetic field or strain is varied. The dramatic anisotropy reflects one-dimensional localization (directional localization) of the electron wave functions along a crystal axis due to quantum interference effects. This can be understood in an effective one-dimensional quasiperiodic Aubry-André-Harper-like model, or in a complementary semiclassical picture. This phenomenon should be observable in strained moiré materials at realistic fields and low strain disorder, as well as unstrained systems with anisotropic Fermi surfaces.

8.
Water Sci Technol ; 90(1): 270-286, 2024 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-39007319

RESUMEN

The completely autotrophic nitrogen removal over nitrite (CANON) process is significantly hindered by prolonged start-up periods and unstable nitrogen removal efficiency. In this study, a novel umbrella basalt fiber (BF) carrier with good biological affinity and adsorption performance was used to initiate the CANON process. The CANON process was initiated on day 64 in a sequencing batch reactor equipped with umbrella BF carriers. During this period, the influent NH4+-N concentration gradually increased from 100 to 200 mg·L-1, and the dissolved oxygen was controlled below 0.8 mg L-1. Consequently, an average ammonia nitrogen removal efficiency (ARE) and total nitrogen removal efficiency (TNRE) of ∼90 and 80% were achieved, respectively. After 130 days, ARE and TNRE remained stable at 92 and 81.1%, respectively. This indicates a reliable method for achieving rapid start-up and stable operation of the CANON process. Moreover, Candidatus Kuenenia and Candidatus Brocadia were identified as dominant anammox genera on the carrier. Nitrosomonas was the predominant genus among ammonia-oxidizing bacteria. Spatial differences were observed in the microbial population of umbrella BF carriers. This arrangement facilitated autotrophic nitrogen removal in a single reactor. This study indicates that the novel umbrella BF carrier is a highly suitable biocarrier for the CANON process.


Asunto(s)
Procesos Autotróficos , Reactores Biológicos , Nitritos , Nitrógeno , Nitrógeno/química , Nitritos/química , Eliminación de Residuos Líquidos/métodos , Bacterias/metabolismo
9.
Front Neurol ; 15: 1388544, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38974688

RESUMEN

Background: The treatment of multidrug-resistant tuberculosis (MDR-TB) and pre-extensively drug-resistant tuberculosis (pre-XDR-TB) remains challenging due to the limited availability of effective drugs. Linezolid has emerged as a promising therapeutic option for these cases. However, its long-term use can lead to complications such as peripheral and optic neuropathies. Acupuncture, a cornerstone of traditional Chinese medicine, has been shown to be effective in the treatment of peripheral neuropathy (PN). This study examines the potential benefits of acupuncture in the treatment of linezolid-induced peripheral neuropathy (LIPN). Methods: Four patients, aged 27 to 60 years, diagnosed with LIPN, underwent daily acupuncture treatments. The main endpoint was to assess the efficacy of acupuncture in reducing neuropathic pain associated with LIPN in patients. This was primarily measured using changes in the Short Form McGill Pain Questionnaire (SF-MPQ) scores before and after acupuncture treatment. Results: Three of the patients experienced significant symptom remission, while one experienced marginal improvement. Treatments ranged from 7 to 18 sessions. Specifically, the first patient reported substantial relief with a score reduction from 33 to 13; the second patient observed minimal change; the third patient's score decreased dramatically from 10 to 2 after eight sessions; the last patient had a score reduction from 21 to 12 after five sessions, but did not continue treatment for a second assessment. Conclusion: Acupuncture is a promising therapeutic approach for LIPN. However, larger and more thorough studies are needed to determine its full potential.

10.
Sci Adv ; 10(28): eadn0929, 2024 Jul 12.
Artículo en Inglés | MEDLINE | ID: mdl-38996015

RESUMEN

Polar metals are challenging to identify spectroscopically because the fingerprints of electric polarization are often obscured by the presence of screening charges. Here, we unravel unambiguous signatures of a distortive polar order buried in the Fermi sea by probing the nonlinear optical response of materials driven by tailored terahertz fields. We apply this strategy to investigate the topological crystalline insulator Pb1-xSnxTe, tracking its soft phonon mode in the time domain and observing the occurrence of inversion symmetry breaking as a function of temperature. By combining measurements across the material's phase diagram with ab initio calculations, we demonstrate the generality of our approach. These results highlight the potential of terahertz driving fields to reveal polar orders coexisting with itinerant electrons, thus opening additional avenues for material discovery.

11.
Curr Med Imaging ; 20: e15734056302538, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38874028

RESUMEN

BACKGROUND: Radiomics can quantify pulmonary nodule characteristics non-invasively by applying advanced imaging feature algorithms. Radiomic textural features derived from Computed Tomography (CT) imaging are broadly used to predict benign and malignant pulmonary nodules. However, few studies have reported on the radiomics-based identification of nodular Pulmonary Cryptococcosis (PC). OBJECTIVE: This study aimed to evaluate the diagnostic and differential diagnostic value of radiomic features extracted from CT images for nodular PC. METHODS: This retrospective analysis included 44 patients with PC (29 males, 15 females), 58 with Tuberculosis (TB) (39 males, 19 females), and 60 with Lung Cancer (LC) (20 males, 40 females) confirmed pathologically. Models 1 (PC vs. non-PC), 2 (PC vs. TB), and 3 (PC vs. LC) were established using radiomic features. Models 4 (PC vs. TB) and 5 (PC vs. LC) were established based on radiomic and CT features. RESULTS: Five radiomic features were predictive of PC vs. non-PC model, but accuracy and Area Under the Curve (AUC) were 0.49 and 0.472, respectively. In model 2 (PC vs. TB) involving six radiomic features, the accuracy and AUC were 0.80 and 0.815, respectively. Model 3 (PC vs. LC) with six radiomic features performed well, with AUC=0.806 and an accuracy of 0.76. Between the PC and TB groups, model 4 combining radiomics, distribution, and PI, showed AUC=0.870. In differentiating PC from LC, the combination of radiomics, distribution, PI, and RBNAV achieved AUC=0.926 and an accuracy of 0.90. CONCLUSION: The prediction models based on radiomic features from CT images performed well in discriminating PC from TB and LC. The individualized prediction models combining radiomic and CT features achieved the best diagnostic performance.


Asunto(s)
Criptococosis , Enfermedades Pulmonares Fúngicas , Tomografía Computarizada por Rayos X , Humanos , Masculino , Femenino , Tomografía Computarizada por Rayos X/métodos , Criptococosis/diagnóstico por imagen , Estudios Retrospectivos , Persona de Mediana Edad , Enfermedades Pulmonares Fúngicas/diagnóstico por imagen , Anciano , Diagnóstico Diferencial , Adulto , Neoplasias Pulmonares/diagnóstico por imagen , Radiómica
12.
ACS Appl Mater Interfaces ; 16(26): 33416-33427, 2024 Jul 03.
Artículo en Inglés | MEDLINE | ID: mdl-38904246

RESUMEN

As a novel electrochemical energy conversion device, direct ethanol fuel cells are currently encountering two significant challenges: CO poisoning and the difficulty of C-C bond cleavage in ethanol. In this work, an amorphous PdS nanowires/ultrafine IrMnOx bimetallic oxides (denoted as a-PdS/IrMnOx NWs) catalyst with abundant oxide/metal (crystalline/amorphous) inverse heterogeneous interfaces was synthesized via a hydrothermal process succeeded by a nonthermal air-plasma treatment. This unique interfacial electronic structure along with the incorporation of oxyphilic metal has resulted in a significant enhancement in the electrocatalytic performance of a-PdS/IrMnOx NWs toward the ethanol oxidation reaction, achieving current densities of 12.45 mA·cm-2 and 3.68 A·mgPd-1. Moreover, the C1 pathway selectivity for ethanol oxidation has been elevated to 47%, exceeding that of other as-prepared Pd-based counterparts and commercial Pd/C catalysts. Density functional theory calculations have validated the findings that the decoration of IrMn species onto the amorphous PdS surface has induced a charge redistribution in the interface region. The redistribution of surface charges on the a-PdS/IrMnOx NWs catalyst results in a significant decrease in the activation energy required for C-C bond cleavage and a notable weakening of the CO binding strength at the Pd active sites. Consequently, it enhanced both the EOR C1 pathway selectivity and CO poisoning resistance to the a-PdS/IrMnOx NWs catalyst.

13.
J Transl Med ; 22(1): 596, 2024 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-38926764

RESUMEN

BACKGROUND: Existing studies have found that circular RNAs (circRNAs) act as sponges for micro RNAs (miRNAs) to control downstream genes. However, the specific functionalities and mechanisms of circRNAs in human clear cell renal cell carcinoma (ccRCC) have yet to be thoroughly investigated. METHODS: Patient cohorts from online databases were used to screen candidate circRNAs, while another cohort from our hospital was obtained for validation. CircSOD2 was identified as a potential oncogenic target, and its relevant characteristics were investigated during ccRCC progression through various assays. A positive feedback loop containing downstream miRNA and its target gene were identified using bioinformatics and validated by luciferase reporter assays, RNA pull-down, and high-throughput sequencing. RESULTS: CircSOD2 expression was elevated in tumor samples and significantly correlated with overall survival (OS) and the tumor stage of ccRCC patients, which appeared in the enhanced proliferation, invasion, and migration of tumor cells. Through competitive binding to circSOD2, miR-532-3p can promote the expression of PAX5 and the progression of ccRCC, and such regulation can be salvaged by miR-532-3p inhibitor. CONCLUSION: A novel positive feedback loop, PAX5/circSOD2/miR-532-3p/PAX5 was identified in the study, indicating that the loop may play an important role in the diagnosis and prognostic prediction in ccRCC patients.


Asunto(s)
Carcinoma de Células Renales , Proliferación Celular , Retroalimentación Fisiológica , Regulación Neoplásica de la Expresión Génica , Neoplasias Renales , MicroARNs , ARN Circular , Humanos , Carcinoma de Células Renales/genética , Carcinoma de Células Renales/patología , Carcinoma de Células Renales/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , Neoplasias Renales/genética , Neoplasias Renales/patología , Neoplasias Renales/metabolismo , MicroARNs/genética , MicroARNs/metabolismo , Línea Celular Tumoral , Proliferación Celular/genética , Femenino , Persona de Mediana Edad , Masculino , Carcinogénesis/genética , Carcinogénesis/patología , Movimiento Celular/genética , Factor de Transcripción PAX5/metabolismo , Factor de Transcripción PAX5/genética , Oncogenes/genética , Secuencia de Bases , Progresión de la Enfermedad , Invasividad Neoplásica , Reproducibilidad de los Resultados
14.
Front Endocrinol (Lausanne) ; 15: 1327903, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38846495

RESUMEN

Objectives: To research the connection between the indexes of the indexes of triglyceride-glucose (TyG) combined with obesity indices and the initial neurological severity and short-term outcome of new-onset acute ischemic stroke. Methods: Data of patients with acute ischemic stroke admitted to the Stroke Ward of the Affiliated Hospital of Beihua University from November 2021 to October 2023, were collected. The two indexes were calculated by combining TyG and obesity indices: TyG-body mass index (TyG-BMI) and TyG-waist circumference (TyG-WC). The National Institute of Health Stroke Scale (NIHSS) was used to assess and group patients with neurological deficits within 24 hours of admission: mild stroke (NIHSS ≤5) and moderate-severe stroke (NIHSS >5). Short-term prognosis was evaluated using the modified Rankin Scale (mRS) at discharge or 14 days after onset of the disease and grouped: good outcome (mRS ≤2) and poor outcome (mRS >2). According to the quartiles of TyG-BMI and TyG-WC, the patients were placed into four groups: Q1, Q2, Q3 and Q4. Multi-factor logistic regression analysis was utilized to evaluate the correlation of TyG-BMI and TyG-WC with the severity and short-term outcome. Results: The study included 456 patients. After adjusting for multiple variables, the results showed that compared with the quartile 1, patients in quartile 4 of TyG-BMI had a reduced risk of moderate-severe stroke [Q4: OR: 0.407, 95%CI (0.185-0.894), P = 0.025]; Patients in quartiles 2, 3 and 4 of TyG-BMI had sequentially lower risk of short-term adverse outcomes [Q2: OR: 0.394, 95%CI (0.215-0.722), P = 0.003; Q3: OR: 0.324, 95%CI (0.163-0.642), P = 0.001; Q4: OR: 0.158, 95%CI (0.027-0.349), P <0.001]; Patients in quartiles 3 and 4 of TyG-WC had sequentially lower risk of moderate-severe stroke [Q3: OR: 0.355, 95%CI (0.173-0.728), P = 0.005; Q4: OR: 0.140, 95%CI (0.056-0.351), P <0.001]; Patients in quartiles 3 and 4 of TyG-WC had sequentially lower risk of short-term adverse outcomes [Q3: OR: 0.350, 95%CI (0.175-0.700), P = 0.003; Q4: OR: 0.178, 95%CI (0.071-0.451), P <0.001]. Conclusions: TyG-WC and TyG-BMI were correlated with the severity and short-term outcome of new-onset acute ischemic stroke. As TyG-WC and TyG-BMI increased, stroke severity decreased and short-term outcome was better.


Asunto(s)
Glucemia , Índice de Masa Corporal , Accidente Cerebrovascular Isquémico , Índice de Severidad de la Enfermedad , Triglicéridos , Humanos , Masculino , Femenino , Accidente Cerebrovascular Isquémico/sangre , Persona de Mediana Edad , Anciano , Triglicéridos/sangre , Pronóstico , Glucemia/análisis , Glucemia/metabolismo , Circunferencia de la Cintura , Obesidad/sangre , Obesidad/complicaciones
15.
Artículo en Inglés | MEDLINE | ID: mdl-38870522

RESUMEN

The commonly-used drug susceptibility testing (DST) relies on bacterial culture and faces shortcomings such as long turnaround time and clone/subclone selection. We developed a targeted deep amplification sequencing (DAS) method directly applied to clinical specimens. In this DAS panel, we examined 941 drug-resistant mutations associated with 20 anti-tuberculosis drugs with an initial amount of 4 pg DNA and reduced clinical testing time from 20 days to two days. A prospective study was conducted using 115 clinical specimens mainly with Xpert® Mycobacterium tuberculosis/rifampicin (Xpert MTB/RIF) assay positive to evaluate drug-resistant mutation detection. DAS was performed on culture-free specimens, while culture-dependent isolates were used for phenotypic DST, DAS, and whole-genome sequencing (WGS). For in silico molecular DST, our result based on DAS panel revealed the similar accuracy to three published reports based on WGS. For 82 isolates, application of DAS showed better sensitivity (93.03% vs. 92.16%), specificity (96.10% vs. 95.02%), and accuracy (91.33% vs. 90.62%) than Mykrobe software using WGS. Compared to culture-dependent WGS, culture-free DAS provides a full picture of sequence variation at population level, exhibiting in detail the gain-and-loss variants caused by bacterial culture. Our study performs a systematic verification of the advantages of DAS in clinical applications and comprehensively illustrates the discrepancy in Mycobacterium tuberculosis before and after culture.

16.
J Asian Nat Prod Res ; 26(10): 1192-1206, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-38794953

RESUMEN

Propolis is a natural resinous compound produced by bees, mixed with their saliva and wax, and has a range of biological benefits, including antioxidant and anti-inflammatory effects. This article reviews the in vivo transformation of propolis flavonoids and their potential influence on drug efficacy. Despite propolis is widely used, there is little research on how the active ingredients of propolis change in the body and how they interact with drugs. Future research will focus on these interactions and the metabolic fate of propolis in vivo.


Asunto(s)
Biotransformación , Flavonoides , Própolis , Própolis/química , Flavonoides/química , Flavonoides/farmacología , Estructura Molecular , Animales , Antioxidantes/farmacología , Antioxidantes/química , Humanos , Antiinflamatorios/farmacología , Antiinflamatorios/química , Abejas
18.
Science ; 384(6696): 647-651, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38723084

RESUMEN

The quantum anomalous Hall effect (QAHE) is a robust topological phenomenon that features quantized Hall resistance at zero magnetic field. We report the QAHE in a rhombohedral pentalayer graphene-monolayer tungsten disulfide (WS2) heterostructure. Distinct from other experimentally confirmed QAHE systems, this system has neither magnetic element nor moiré superlattice effect. The QAH states emerge at charge neutrality and feature Chern numbers C = ±5 at temperatures of up to about 1.5 kelvin. This large QAHE arises from the synergy of the electron correlation in intrinsic flat bands of pentalayer graphene, the gate-tuning effect, and the proximity-induced Ising spin-orbit coupling. Our experiment demonstrates the potential of crystalline two-dimensional materials for intertwined electron correlation and band topology physics and may enable a route for engineering chiral Majorana edge states.

19.
Phys Rev Lett ; 132(19): 196202, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38804948

RESUMEN

We introduce density imbalanced electron-hole bilayers at a commensurate 2:1 density ratio as a platform for realizing novel phases of electrons, excitons, and trions. Through the independently tunable carrier densities and interlayer spacing, competition between kinetic energy, intralayer repulsion, and interlayer attraction yields a rich phase diagram. By a combination of theoretical analysis and numerical calculation, we find a variety of strong-coupling phases in different parameter regions, including quantum crystals of electrons, excitons, and trions. We also propose an "electron-exciton supersolid" phase that features electron crystallization and exciton superfluidity simultaneously. The material realization and experimental signature of these phases are discussed in the context of semiconductor transition metal dichalcogenide bilayers.

20.
ACS Nano ; 18(20): 13073-13083, 2024 May 21.
Artículo en Inglés | MEDLINE | ID: mdl-38718251

RESUMEN

Activating multielectron reactions of sodium superionic conductor (NASICON)-type cathodes toward higher energy density remains imperative to boost their application feasibility. However, multisodium storage with high stability is difficult to achieve due to the sluggish reaction kinetics, irreversible phase transitions, and negative structural degradation. Herein, a kind of NASICON-type Na2.5V1.5Ti0.5(PO4)3/C (NVTP-0.5) hierarchical microsphere consisting of abundant primary nanoparticles is designed, realizing a reversible 3.2-electron reaction with high stability. The optimized NVTP-0.5 cathode demonstrates an ultrahigh discharge capacity of 192.42 mAh g-1, energy density of up to 497.3 Wh kg-1 at 20 mA g-1, and capacity retention ratio of 94.1% after 1000 cycles at 1 A g-1. Additionally, the NVTP-0.5 cathode delivers excellent tolerance to extreme temperatures while also achieving a high-energy density of 400 Wh kg-1 (based on the cathode mass) in a full-cell configuration. Systematic in situ/ex situ analysis results confirm the multisodium storage processes of NVTP-0.5 involving successive redox reactions (V2+/V3+, Ti3+/Ti4+, and V3+/V4+ redox couples) and reversible structure evolution (solid-solution and biphasic mechanisms), which contribute to the high capacity and excellent cycling stability. This work indicates that the rational regulation of components with different functions can unlock more possibilities for the development of NASICON-type cathodes.

SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA