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1.
ChemSusChem ; : e202400556, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38728149

RESUMO

A photoactive covalent organic framework (COF) was built from metalloporphyrin and bipyridine monomers and single-atomic Pt sites were subsequently installed. Integrating photosensitizing metalloporphyrin and substrate-activating Pt(bpy) moieties in a single solid facilitates multielectron transfer and accelerates photocatalytic hydrogen evolution with a maximum production rate of 80.4 mmol h-1 gPt-1 and turnover frequency (TOF) of 15.7 h-1 observed. This work demonstrates that incorporation of single-atomic metal sites with photoactive COFs greatly enhances photocatalytic activity and provides an effective strategy for the design and construction of novel photocatalysts.

2.
Mater Horiz ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38712865

RESUMO

Shape-shifting helical gels have been created by various routes, notably by photolithography. We explore electron-beam lithography as an alternative to prescribe microhelix formation in tethered patterns of pure poly(acrylic acid). Simulations indicate the nanoscale spatial distribution of deposited energy that drives the loss of acid groups and crosslinking. Upon exposure to buffer, a patterned line converts to a 3D helix whose cross section comprises a crosslinked and hydrophobic core surrounded by a high-swelling pH-responsive corona. Through-thickness asymmetries generate out-of-plane bending to drive helix formation. The relative core and corona fractions are determined by the electron dose which in turn controls the helical radius and pitch. Increasing pH substantially raises the swelling stress and the rod elongates plastically. The pitch concurrently changes from minimal to non-minimal. The in-plane asymmetry driving this change can be attributed to shear-band formation in the hydrophobic core. Subsequent pH cycling drives elastic cycling of the helical properties. These findings illustrate the effects of elastoplastic deformation on helical properties and elaborate unique attributes of electron lithography as an alternate means to create shape-shifting structures.

3.
Front Endocrinol (Lausanne) ; 15: 1354426, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38721144

RESUMO

Purpose: Postoperative thyroglobulin (Tg) generally serves as a biomarker to monitor the recurrence or persistence of differentiated thyroid cancer (DTC), whereas it constrains to interference from anti-thyroglobulin antibody (TgAb). This study aimed to determine the value of postoperative TgAb as a surrogate for monitoring tumor status in DTCs with positive TgAb after successful radioactive iodine (RAI) remnant ablation. Methods: We retrospectively enrolled DTC patients with positive (≥40 IU/mL, Roche) postoperative TgAb measurements. An index of TgAb change (ΔTgAb) was defined to describe the TgAb decrease rate. DTC status was defined as either no evidence of disease (NED) or persistent/recurrent disease (PRD). Univariate and multivariate binary logistic analyses were used to identify the independent risk factors of PRD. Receiver operating characteristic (ROC) curves were performed to determine the optimal cutoff values of each risk factor, and DeLong's test was conducted to compare their predictive powers. Kaplan-Meier curves were used to assess the impact of different TgAb trends in the first year on progression-free survival. Results: Of the 232 patients enrolled, the median diagnosis age was 34 years (range, 18-62 years), with a male-to-female ratio of 1:4.66 (41/191). Among them, after a median follow-up of 44 months (range, 4-128 months),183 (78.87%) patients were evaluated as NED, while the other 49 (21.12%) had either persistent (n = 25) or recurrent disease (n = 24). Multivariate regression showed that ΔTgAb (P < 0.001) and lymph node metastasis (LNM) rate (P = 0.009) were independently relevant to the presence of PRD, with optimal cutoff values of 47.0% and 35.1%, respectively. It is important to note that there is a high negative predictive value (96.93%) of ΔTgAb with the cutoff of 47.0%. DeLong's test showed that ΔTgAb alone and the combination of ΔTgAb and LNM rate were significantly greater than the isolated LNM rate (both P < 0.001) in predicting NED, while there was no statistical difference of the predictive power between ΔTgAb and the combination (P = 0.203). Additionally, patients with ΔTgAb >47.0% had longer progression-free survival than those with ΔTgAb ≤47.0% (not reached vs. 50 months, P < 0.001), and those with ΔTgAb >47.0% or negative conversion within the first year after RAI ablation had longer progression-free survival. Conclusion: Our study suggested that ΔTgAb could serve as a valuable indicator of disease status in DTC patients with positive TgAb. A ΔTgAb of >47.0% is conducive to identify those with NED and may help to obviate their overtreatment. The decrease rate and negative conversion of TgAb in the first year were good predictors of disease-free survival in patients.


Assuntos
Autoanticorpos , Neoplasias da Glândula Tireoide , Humanos , Masculino , Feminino , Adulto , Neoplasias da Glândula Tireoide/cirurgia , Neoplasias da Glândula Tireoide/sangue , Neoplasias da Glândula Tireoide/patologia , Neoplasias da Glândula Tireoide/mortalidade , Pessoa de Meia-Idade , Autoanticorpos/sangue , Estudos Retrospectivos , Prognóstico , Adulto Jovem , Adolescente , Recidiva Local de Neoplasia/sangue , Recidiva Local de Neoplasia/patologia , Período Pós-Operatório , Biomarcadores Tumorais/sangue , Tireoidectomia , Tireoglobulina/imunologia , Tireoglobulina/sangue , Radioisótopos do Iodo/uso terapêutico , Seguimentos
4.
Opt Lett ; 49(9): 2241-2244, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38691689

RESUMO

Metasurfaces have provided a flexible platform for designing ultracompact metalenses with unusual functionalities. However, traditional multi-foci metalenses are limited to generating circularly polarized (CP) or linearly polarized (LP) focal points, and the intensity distributions are always inhomogeneous/chaotical between the multiple focal points. Here, an inverse design approach is proposed to optimize the in-plane orientation of each meta-atom in a terahertz (THz) multi-foci metalens that can generate multi-polarized focal points with nearly uniform intensity distributions. As a proof-of-principle example, we numerically and experimentally demonstrate an inversely designed metalens for simultaneously generating multiple CP- and LP-based focal points with homogeneous intensity distributions, leading to a multi-polarized image (rather than the holography). Furthermore, the multi-channel and multi-polarized images consisting of multiple focal points with homogeneous intensity distributions are also numerically demonstrated. The unique approach for inversely designing multi-foci metalens that can generate multi-polarized focal points and images with uniform intensity distributions will enable potential applications in imaging and sensing.

5.
Materials (Basel) ; 17(9)2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38730779

RESUMO

Over the last few decades, there has been a growing discourse surrounding environmental and health issues stemming from drinking water and the discharge of effluents into the environment. The rapid advancement of various sewage treatment methodologies has prompted a thorough exploration of promising materials to capitalize on their benefits. Metal-organic frameworks (MOFs), as porous materials, have garnered considerable attention from researchers in recent years. These materials boast exceptional properties: unparalleled porosity, expansive specific surface areas, unique electronic characteristics including semi-conductivity, and a versatile affinity for organic molecules. These attributes have fueled a spike in research activity. This paper reviews the current MOF-based wastewater removal technologies, including separation, catalysis, and related pollutant monitoring methods, and briefly introduces the basic mechanism of some methods. The scale production problems faced by MOF in water treatment applications are evaluated, and two pioneering methods for MOF mass production are highlighted. In closing, we propose targeted recommendations and future perspectives to navigate the challenges of MOF implementation in water purification, enhancing the efficiency of material synthesis for environmental stewardship.

6.
Inorg Chem ; 63(19): 8822-8831, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38696545

RESUMO

This study presents the rare examples of S-heteroaryl tetradentate Pt(S^C^N^O) luminescent complexes (PtSZ and PtSZtBu) containing a Pt-S bond. The presence of the Pt-S bond allows the novel Pt(S^C^N^O) complexes to exhibit temperature-dependent phosphorescent emission behavior. The PtSZtBu exhibits dual-emission phenomena and biexponential transient decay spectra above 250 K, indicating the presence of two minimal excited states in the potential energy surface (PES) of the T1 state. Through complementary experimental and computational studies, we have identified changes in orbital composition between Pt(dxy)-S(px) and Pt(dyz)-S(pz) in excited states with increasing temperature. This results in two energy minima, enabling the excited states to decay selectively and radiatively at different temperatures. Consequently, this leads to remarkable steady-state and transient emission spectra changes. Our work not only provides valuable insights for the development of novel Pt-S bond-based tetradentate Pt(II) complexes but also enhances our understanding of the distinctive properties governed by the Pt-S bond.

7.
ACS Energy Lett ; 9(4): 1617-1623, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38633996

RESUMO

A hierarchical transparent back contact leveraging an AlGaOx passivating layer, Ti3C2Tx MXene with a high work function, and a transparent cracked film lithography (CFL) templated nanogrid is demonstrated on copper-free cadmium telluride (CdTe) devices. AlGaOx improves device open-circuit voltage but reduces the fill factor when using a CFL-templated metal contact. Including a Ti3C2Tx interlayer improves the fill factor, lowers detrimental Schottky barriers, and enables metallization with CFL by providing transverse conduction into the nanogrid. The bifacial performance of an AlGaOx/Ti3C2Tx/CFL gold contact is evaluated, reaching 19.5% frontside efficiency and 2.8% backside efficiency under 1-sun illumination for a copper-free, group-V doped CdTe device. Under dual illumination, device power generation reached 200 W/m2 with 0.1 sun backside illumination.

8.
Arch Biochem Biophys ; 755: 109983, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38561035

RESUMO

Apelin (APLN) is an endogenous ligand of the G protein-coupled receptor APJ (APLNR). APLN has been implicated in the development of multiple tumours. Herein, we determined the effect of APLN on the biological behaviour and underlying mechanisms of cervical cancer. The expression and survival curves of APLN were determined using Gene Expression Profiling Interactive Analysis. The cellular functions of APLN were detected using CCK-8, clone formation, EdU, Transwell assays, flow cytometry, and seahorse metabolic analysis. The underlying mechanisms were elucidated using gene set enrichment analysis and Western blotting. APLN was upregulated in the samples of patients with cervical cancer and is associated with poor prognosis. APLN knockdown decreased the proliferation, migration, and glycolysis of cervical cancer cells. The opposite results were observed when APLN was overexpressed. Mechanistically, we determined that APLN was critical for activating the PI3K/AKT/mTOR pathway via APLNR. APLN receptor inhibitor ML221 reversed the effect of APLN overexpression on cervical cancer cells. Treatment with LY294002, the PI3K inhibitor, drastically reversed the oncological behaviour of APLN-overexpressing C-33A cells. APLN promoted the proliferation, migration, and glycolysis of cervical cancer cells via the PI3K/AKT/mTOR pathway.

9.
Front Neurol ; 15: 1372861, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38633537

RESUMO

Background: Immune checkpoint inhibitors (ICI)-induced myasthenia gravis (MG) is an uncommon but potentially fatal neurotoxicity. We aim to help physicians familiarize themselves with the clinical characteristics of ICI-induced MG, facilitating early diagnosis and prompt intervention. Methods: We searched the Chinese People's Liberation Army General Hospital medical record system from January 2017 to August 2023 for patients diagnosed with ICI-induced MG. We systematically reviewed the literature until August 2023 to identify all similar patients. We collected clinical information on these patients. Results: 110 patients were identified, 9 from our institution and 101 from case reports. In our institution, Median age was 66 years (range: 49-79 years). 6 were males. The most common was lung cancer (n = 4). All patients had no previous history of MG and received PD-1 or PD-L1 inhibitors. The median time from ICI initiation to first MG symptoms was 4 weeks (range: 2-15 weeks). ICIs were discontinued in all patients. Most patients initially received high-dose corticosteroids, and their symptoms improved. Some patients are discharged with corticosteroids maintenance therapy. In addition, 55 patients (50%) with concomitant myositis and/or myocarditis and MG-induced mortality were more common in the myositis and/or myocarditis group (10.9% vs. 34.5%, p = 0.016). Overlap of myositis with MG (OR = 3.148, p = 0.009) and anti-AChR antibody positivity (OR = 3.364, p = 0.005) were both significantly associated with poor outcomes. Conclusion: Our study reveals the prognosis of ICI-induced MG and suggests that myositis and/or myocarditis are severe comorbidities of ICI-induced MG, emphasizing the importance of early diagnosis and clinical intervention.

10.
Methods ; 226: 61-70, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38631404

RESUMO

As the most abundant mRNA modification, m6A controls and influences many aspects of mRNA metabolism including the mRNA stability and degradation. However, the role of specific m6A sites in regulating gene expression still remains unclear. In additional, the multicollinearity problem caused by the correlation of methylation level of multiple m6A sites in each gene could influence the prediction performance. To address the above challenges, we propose an elastic-net regularized negative binomial regression model (called m6Aexpress-enet) to predict which m6A site could potentially regulate its gene expression. Comprehensive evaluations on simulated datasets demonstrate that m6Aexpress-enet could achieve the top prediction performance. Applying m6Aexpress-enet on real MeRIP-seq data from human lymphoblastoid cell lines, we have uncovered the complex regulatory pattern of predicted m6A sites and their unique enrichment pathway of the constructed co-methylation modules. m6Aexpress-enet proves itself as a powerful tool to enable biologists to discover the mechanism of m6A regulatory gene expression. Furthermore, the source code and the step-by-step implementation of m6Aexpress-enet is freely accessed at https://github.com/tengzhangs/m6Aexpress-enet.

12.
J Am Chem Soc ; 146(18): 12444-12453, 2024 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-38680118

RESUMO

Open Cu sites were loaded to the UiO-67 metal-organic framework (MOF) skeleton by introduction of flexible Cu-binding pyridylmethylamine (pyma) side chains to the biphenyldicarboxylate linkers. Distance between Cu centers in the MOF pores was tuned by controlling the density of metal-binding side chains. "Interacted" Cu-pair or "isolated" monomeric Cu sites were achieved with high and low (pyma)Cu side chain loading, respectively. Spectroscopic and theoretical studies indicate that "interacted" Cu pairs can effectively bind and activate molecular dioxygen to form Cu2O2 clusters, which showed high catalytic activity for aerobic oxidative C-N coupling. On the contrary, MOF catalyst bearing isolated monomeric Cu sites only showed modest catalytic activity. Enhancement in catalytic performance for the Cu-pair catalyst is attributed to the remote synergistic effect of the paired Cu site, which binds molecular dioxygen and cleaves the O═O bond in a collaborative manner. This work demonstrates that noncovalently interacted metal-pair sites can effectively activate inert small molecules and promote heterogeneous catalytic processes.

13.
ACS Nano ; 18(18): 11933-11940, 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38663413

RESUMO

In this study, a comprehensive characterization was conducted on a chiral starburst molecule (C57H48N4, SBM) using scanning tunneling microscopy. When adsorbed onto the hBN/Rh(111) nanomesh, these molecules demonstrate homochiral recognition, leading to a selective formation of homochiral dimers. Further tip manipulation experiments reveal that the chiral dimers are stable and primarily controlled by strong intermolecular interactions. Density functional theory (DFT) calculations supported that the chiral recognition of SBM molecules is governed by the intermolecular charge transfer mechanism, different from the common steric hindrance effect. This study emphasizes the importance of intermolecular charge transfer interactions, offering valuable insights into the chiral recognition of a simple bimolecular system. These findings hold significance for the future advancement in chirality-based electronic sensors and pharmaceuticals, where the chirality of molecules can impact their properties.

14.
Biochem Pharmacol ; 224: 116240, 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38679210

RESUMO

Hepatic steatosis is a critical factor in the development of nonalcoholic steatohepatitis (NASH). Sesamin (Ses), a functional lignan isolated from Sesamum indicum, possesses hypolipidemic, liver-protective, anti-hypertensive, and anti-tumor properties. Ses has been found to improve hepatic steatosis, but the exact mechanisms through which Ses achieves this are not well understood. In this study, we observed the anti-hepatic steatosis effects of Ses in palmitate/oleate (PA/OA)-incubated primary mouse hepatocytes, AML12 hepatocytes, and HepG2 cells, as well as in high-fat, high-cholesterol diet-induced NASH mice. RNA sequencing analysis revealed that cluster of differentiation 36 (CD36), a free fatty acid (FA) transport protein, was involved in the Ses-mediated inhibition of hepatic fat accumulation. Moreover, the overexpression of CD36 significantly increased hepatic steatosis in both Ses-treated PA/OA-incubated HepG2 cells and NASH mice. Furthermore, Ses treatment suppressed insulin-induced de novo lipogenesis in HepG2 cells, which was reversed by CD36 overexpression. Mechanistically, we found that Ses ameliorated NASH by inhibiting CD36-mediated FA uptake and upregulation of lipogenic genes, including FA synthase, stearoyl-CoA desaturase 1, and sterol regulatory element-binding protein 1. The findings of our study provide novel insights into the potential therapeutic applications of Ses in the treatment of NASH.

15.
Artigo em Inglês | MEDLINE | ID: mdl-38583495

RESUMO

PURPOSE: The aim of this study was to compare the clinical benefit and safety of the triple combination of stereotactic body radiotherapy (SBRT), lenvatinib, and programmed cell death protein 1 (PD-1) inhibitors with the dual combination of SBRT and lenvatinib in patients with unresectable hepatocellular carcinoma (uHCC). METHODS AND MATERIALS: Patients with uHCC who received SBRT in combination with lenvatinib and PD-1 inhibitors or SBRT in combination with lenvatinib alone as first-line treatment from October 2018 to July 2022 were reviewed in this study. The primary endpoints were overall survival (OS) and progression-free survival (PFS). The secondary endpoints were intrahepatic PFS, extrahepatic PFS, and objective remission rate. In addition, safety profiles were assessed by analyzing treatment-related adverse events between the two groups to assess safety profiles. RESULTS: In total, 214 patients with uHCC who received combination therapy were included in this retrospective study. Among them, 146 patients received triple combination therapy of SBRT, lenvatinib, and PD-1 inhibitors (SBRT-L-P group), and 68 patients received dual therapy of SBRT and lenvatinib (SBRT-L group). The median OS times of the 2 groups were 31.2 months and 17.4 months, respectively (P < .001). The median PFS time was significantly longer in the SBRT-L-P group than in the SBRT-L group (15.6 months vs 8.8 months, P < .001). Additionally, the median intrahepatic PFS (17.5 vs 9.9 months, P < .001) and extrahepatic PFS (20.9 vs 11.6 months, P < .001) were significantly longer in the SBRT-L-P group than in the SBRT-L group. The objective remission rate in the SBRT-L-P group was higher than in the SBRT-L group (63.0 vs 39.7%, P = .002). The incidence and severity of treatment-related adverse events in the SBRT-L-P group were comparable to those in the SBRT-L group. CONCLUSION: The use of both lenvatinib and PD-1 inhibitors with SBRT in patients with uHCC was associated with improved overall survival compared with lenvatinib and SBRT alone with a manageable safety profile.

17.
Front Surg ; 11: 1307460, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38486796

RESUMO

Introduction: The Tarlov cysts are pathological enlargements of the cerebrospinal fluid spaces between the endoneurium and perineurium, which can cause intolerable sciatic pain, motor impairment of lower limbs, and bladder/bowel dysfunction. Currently, the treatment results are unsatisfactory due to the low cure rates and extensive surgical trauma. Thus, there is an ongoing exploration of surgical techniques for Tarlov treatment. In the current study, we present a novel neuroendoscopic-assisted technique that combines the fenestration, leakage sealing, and tamponade of the Tarlov cyst. Methods: Between January 2020 and December 2021, a total of 32 Tarlov patients were enrolled and received neuroendoscopic-assisted surgery. Their pre- and post-surgical Visual Analogue Scale (VAS) scores, major complaints, and MR imaging were recorded for comparison. Results: 27 of 32 patients (84.4%) patients demonstrated immediate pain relief as their VAS scores decreased from 5.6 ± 1.5 to 2.5 ± 1.1 (p < 0.01) on the first day after surgery. At the 3-month follow-up, the patients' average VAS score continued to decrease (1.94 ± 0.8). Meanwhile, saddle paresthesia, urinary incontinence, and constipation were relieved in 6 (50%), 4 (80%), and 5 (41.7%), respectively, according to patients self-report. No surgical-related complication was observed in any of the cases. Discussion: We conclude that neuroendoscopic-assisted surgery is an effective surgical method for symptomatic Tarlov cysts with minimized complications.

18.
Opt Lett ; 49(6): 1544-1547, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489446

RESUMO

Terahertz (THz) metasurfaces have opened up a new avenue for the THz wavefront modulation. However, high-efficient and low-cost fabrication of THz metasurfaces remains a great challenge today. Here, quasi-capsule-shaped polarization-multiplexed holographic THz metasurfaces were printed by a beam-shaped femtosecond laser. The laser beam was spatially modulated by holograms of optimized cylindrical lens loaded on a spatial light modulator (SLM). The size of quasi-capsule apertures can be exquisitely and flexibly controlled by adjusting the focal length in holograms, pulse energy, and pulse number. Based on near-field diffraction and Burch encoding, an array of 100 × 100 basic unit apertures were initially designed, and a polarization-multiplexed THz metasurface was finally printed with a dimension of 8 mm × 8 mm. The function of polarization multiplexing was demonstrated, by which two kinds of images were reconstructed in response to X and Y-polarization THz waves, respectively. The present work highlights a great leap in fabrication method for THz metasurfaces and hopefully stimulates the development of miniaturized and integrated THz systems.

19.
Int J Surg ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38489557

RESUMO

BACKGROUND: Currently, there is a lack of ideal risk prediction tools in the field of emergency general surgery (EGS). The American Association for the Surgery of Trauma recommends developing risk assessment tools specifically for EGS-related diseases. In this study, we sought to utilize machine learning (ML) algorithms to explore and develop a web-based calculator for predicting five perioperative risk events of eight common operations in EGS. METHOD: This study focused on patients with EGS and utilized electronic medical record systems to obtain data retrospectively from five centers in China. Five ML algorithms, including Random Forest (RF), Support Vector Machine, Naive Bayes, XGBoost, and Logistic Regression, were employed to construct predictive models for postoperative mortality, pneumonia, surgical site infection, thrombosis, and mechanical ventilation >48 h. The optimal models for each outcome event were determined based on metrics, including the value of the Area Under the Curve, F1 score, and sensitivity. A comparative analysis was conducted between the optimal models and Emergency Surgery Score (ESS), Acute Physiology and Chronic Health Evaluation II (APACHE II) score, and American Society of Anesthesiologists (ASA) classification. A web-based calculator was developed to determine corresponding risk probabilities. RESULT: Based on 10,993 patients with EGS, we determined the optimal RF model. The RF model also exhibited strong predictive performance compared with the ESS, APACHE II score, and ASA classification. Using this optimal model, we developed an online calculator with a questionnaire-guided interactive interface, catering to both the preoperative and postoperative application scenarios. CONCLUSIONS: We successfully developed an ML-based calculator for predicting the risk of postoperative adverse events in patients with EGS. This calculator accurately predicted the occurrence risk of five outcome events, providing quantified risk probabilities for clinical diagnosis and treatment.

20.
Nat Commun ; 15(1): 2336, 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38485980

RESUMO

Quantum spin liquids (QSLs) are in a quantum disordered state that is highly entangled and has fractional excitations. As a highly sought-after state of matter, QSLs were predicted to host spinon excitations and to arise in frustrated spin systems with large quantum fluctuations. Here we report on the experimental observation and theoretical modeling of QSL signatures in monolayer 1T-NbSe2, which is a newly emerging two-dimensional material that exhibits both charge-density-wave (CDW) and correlated insulating behaviors. By using scanning tunneling microscopy and spectroscopy (STM/STS), we confirm the presence of spin fluctuations in monolayer 1T-NbSe2 by observing the Kondo resonance as monolayer 1T-NbSe2 interacts with metallic monolayer 1H-NbSe2. Subsequent STM/STS imaging of monolayer 1T-NbSe2 at the Hubbard band energy further reveals a long-wavelength charge modulation, in agreement with the spinon modulation expected for QSLs. By depositing manganese-phthalocyanine (MnPc) molecules with spin S = 3/2 onto monolayer 1T-NbSe2, new STS resonance peaks emerge at the Hubbard band edges of monolayer 1T-NbSe2. This observation is consistent with the spinon Kondo effect induced by a S = 3/2 magnetic impurity embedded in a QSL. Taken together, these experimental observations indicate that monolayer 1T-NbSe2 is a new promising QSL material.

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