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1.
Nat Mater ; 23(3): 331-338, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37537355

RESUMO

The properties of two-dimensional (2D) van der Waals materials can be tuned through nanostructuring or controlled layer stacking, where interlayer hybridization induces exotic electronic states and transport phenomena. Here we describe a viable approach and underlying mechanism for the assisted self-assembly of twisted layer graphene. The process, which can be implemented in standard chemical vapour deposition growth, is best described by analogy to origami and kirigami with paper. It involves the controlled induction of wrinkle formation in single-layer graphene with subsequent wrinkle folding, tearing and re-growth. Inherent to the process is the formation of intertwined graphene spirals and conversion of the chiral angle of 1D wrinkles into a 2D twist angle of a 3D superlattice. The approach can be extended to other foldable 2D materials and facilitates the production of miniaturized electronic components, including capacitors, resistors, inductors and superconductors.

2.
Nano Lett ; 23(12): 5770-5778, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37314049

RESUMO

Understanding the atomistic mechanisms of non-equilibrium processes during solid-state synthesis, such as nucleation and grain structure formation of a layered oxide phase, is a critical challenge for developing promising cathode materials such as Ni-rich layered oxide for Li-ion batteries. In this study, we found that the aluminum oxide coating layer transforms into lithium aluminate as an intermediate, which has favorable low interfacial energies with the layered oxide to promote the nucleation of the latter. The fast and uniform nucleation and formation of the layered oxide phase at relatively low temperatures were evidenced using solid-state nuclear magnetic resonance and in situ synchrotron X-ray diffraction. The resulting Ni-rich layered oxide cathode has fine primary particles, as visualized by three-dimensional tomography constructed using a focused-ion beam and scanning electron microscopy. The densely packed fine primary particles enable the excellent mechanical strength of the secondary particles, as demonstrated by in situ compression tests. This strategy provides a new approach for developing next-generation, high-strength battery materials.

3.
Int J Clin Pract ; 75(12): e14907, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34551174

RESUMO

OBJECTIVE: The association between computed tomography (CT) and clinical severity of COVID-19 has been demonstrated. However, there are few studies on CT and laboratory indicators in patients in COVID-19. Our aim was to explore the correlation between chest CT images and laboratory indicators of patients with COVID-19 pneumonia. METHODS: This was a retrospective study of patients with COVID-19 diagnosed and treated at the Affiliated Hospital of Putian University from 24 January 2020 to 6 March 2020. The correlation test between first chest CT score and blood cell analysis, C-reactive protein (CRP), erythrocyte sedimentation rate (ESR), blood biochemistry and T lymphocyte subsets (T-Ls) was investigated. RESULTS: Among the 56 patients, there were 36 (64.3%) males and 20 (35.7%) females. The mean age of the patients was 46.54 ± 15.82 (range, 15-86) years. The CT score in the moderate group was higher than in the mild group (5.06 ± 0.77 vs 1.87 ± 0.88, P < .05), and higher in the severe group than in the moderate and mild groups (10.71 ± 4.21, P < .05). In addition, the ESR was significantly higher in the severe group than mild group (32.00 (26.04, 58.24) vs 11.00 (7.84, 24.70) mm/h, P < .05). The CD3, CD4, CD8 and CD4/CD8 cells were not different (all P > .05). The CT scores of all patients correlated positively with CRP, LDH and ESR (all P < .01). CONCLUSION: The chest CT characteristics of patients with COVID-19 correlated positively with CRP, ESR and LDH, which may use one of the indicators for the assessment of disease severity.


Assuntos
COVID-19 , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Laboratórios , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2 , Tomografia Computadorizada por Raios X , Adulto Jovem
4.
Am J Clin Oncol ; 46(4): 161-166, 2023 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-36806256

RESUMO

OBJECTIVE: To discuss the efficacy and potential prognostic factors of immune checkpoint inhibitors (ICIs) in patients with advanced non-small cell lung cancer (NSCLC). METHODS: A retrospective study was conducted to analyze the medical history of patients (n=111) confirmed with advanced NSCLC in the Affiliated Hospital of Putian University from 2018 to 2020. All enrolled patients with adenocarcinoma (n=69), squamous cell carcinoma (n=28), and other types of lung cancer (n=14) were treated with the programmed death-ligand 1 (PD-1) inhibitors. They were divided into groups of PD-1 inhibitors, PD-1 inhibitors in combination with chemotherapy, and PD-1 inhibitors in combination with chemotherapy and angiogenesis inhibitors according to the treatment regimen. General clinical data of all patients were collected, and the Kaplan-Meier analysis was applied to estimate progression-free survival (PFS) and overall survival (OS). In addition, univariate and multivariate Cox regression analyses were performed to analyze prognostic factors associated with PFS and OS after treatment. RESULTS: Of 111 patients with advanced NSCLC treated with ICIs, 6 were fully responsive, 33 were partially responsive, 55 were stable, and 17 were progressive. There was no significant difference in objective response rate between the 3 groups. In the subgroup analysis according to the lines of therapy, the objective response rate of patients receiving first-line treatment was 46.7%, which was significantly higher than that of other line treatment groups ( P =0.014). The results of multivariate Cox regression analysis indicated that the history of hormone use (HR=1.593; P =0.033), second-line or further lines of therapy (HR=2.871; P <0.001), and high neutrophil/lymphocyte ratio (NLR; HR=1.498; P =0.045) were independent risk factors for PFS after immunotherapy for advanced NSCLC. And the history of hormone use (HR=1.518; P =0.015) and high NLR (HR=3.053; P =0.001) were as well the independent risk factors for OS after immunotherapy for advanced NSCLC. CONCLUSION: ICIs therapy clearly had a greater survival benefit in patients who received first-line therapy, had no history of hormone use, and showed low NLR after initial treatment. ICIs can be an effective treatment for advanced NSCLC.


Assuntos
Antineoplásicos Imunológicos , Carcinoma Pulmonar de Células não Pequenas , Neoplasias Pulmonares , Humanos , Carcinoma Pulmonar de Células não Pequenas/patologia , Neoplasias Pulmonares/patologia , Inibidores de Checkpoint Imunológico/uso terapêutico , Prognóstico , Estudos Retrospectivos , Antineoplásicos Imunológicos/uso terapêutico , Biomarcadores Tumorais/análise
5.
Nat Commun ; 14(1): 7447, 2023 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-37978192

RESUMO

The atomic-thick anticorrosion coating for copper (Cu) electrodes is essential for the miniaturisation in the semiconductor industry. Graphene has long been expected to be the ultimate anticorrosion material, however, its real anticorrosion performance is still under great controversy. Specifically, strong electronic couplings can limit the interfacial diffusion of corrosive molecules, whereas they can also promote the surficial galvanic corrosion. Here, we report the enhanced anticorrosion for Cu simply via a bilayer graphene coating, which provides protection for more than 5 years at room temperature and 1000 h at 200 °C. Such excellent anticorrosion is attributed to a nontrivial Janus-doping effect in bilayer graphene, where the heavily doped bottom layer forms a strong interaction with Cu to limit the interfacial diffusion, while the nearly charge neutral top layer behaves inertly to alleviate the galvanic corrosion. Our study will likely expand the application scenarios of Cu under various extreme operating conditions.

6.
Adv Mater ; 35(36): e2302568, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37285053

RESUMO

Fe3 GeTe2 have proven to be of greatly intrigue. However, the underlying mechanism behind the varying Curie temperature (Tc ) values remains a puzzle. This study explores the atomic structure of Fe3 GeTe2 crystals exhibiting Tc values of 160, 210, and 230 K. The elemental mapping reveals a Fe-intercalation on the interstitial sites within the van der Waals gap of the high-Tc (210 and 230 K) samples, which are observed to have an exchange bias effect by electrical transport measurements, while Fe intercalation or the bias effect is absent in the low-Tc (160 K) samples. First-principles calculations further suggest that the Fe-intercalation layer may be responsible for the local antiferromagnetic coupling that gives rise to the exchange bias effect, and that the interlayer exchange paths greatly contribute to the enhancement of Tc . This discovery of the Fe-intercalation layer elucidates the mechanism behind the hidden antiferromagnetic ordering that underlies the enhancement of Tc in Fe3 GeTe2 .

7.
ACS Nano ; 16(2): 3251-3263, 2022 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-35089016

RESUMO

Strain engineering in bimetallic alloy structures is of great interest in electrochemical CO2 reduction reactions (CO2RR), in which it simultaneously improves electrocatalytic activity and product selectivity by optimizing the binding properties of intermediates. However, a reliable synthetic strategy and systematic understanding of the strain effects in the CO2RR are still lacking. Herein, we report a strain relaxation strategy used to determine lattice strains in bimetal MNi alloys (M = Pd, Ag, and Au) and realize an outstanding CO2-to-CO Faradaic efficiency of 96.6% and show the outstanding activity and durability toward a Zn-CO2 battery. Molecular dynamics (MD) simulations predict that the relaxation of strained PdNi alloys (s-PdNi) is correlated with increases in synthesis temperature, and the high temperature activation energy drives complete atomic mixing of multiple metal atoms to allow for regulation of lattice strains. Density functional theory (DFT) calculations reveal that strain relaxation effectively improves CO2RR activity and selectivity by optimizing the formation energies of *COOH and *CO intermediates on s-PdNi alloy surfaces, as also verified by in situ spectroscopic investigations. This approach provides a promising approach for catalyst design, enabling independent optimization of formation energies of reaction intermediates to improve catalytic activity and selectivity simultaneously.

8.
Medicine (Baltimore) ; 100(10): e25005, 2021 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-33725880

RESUMO

ABSTRACT: The role of thoracic CT (computerized tomography) in monitoring disease course of COVID-19 is controversial. The purpose of this study is to investigate the risk factors and predictive value of deterioration on repeatedly performed CT scan during hospitalization.All COVID-19 patients treated in our isolation ward, from January 22, 2020 to February 7, 2020, were reviewed. Patients included were categorized into RD (Radiological Deterioration) group or NRD (No Radiological Deterioration) group according to the manifestation on the CT routinely performed during the hospitalization. All clinical data and CT images were analyzed.Forty three patients were included in our study. All are moderate cases with at least 4 CT scans each. Eighteen (42.9%) patients had radiological deteriorations which were all identified in CT2 (the first CT after admission). Patients in RD group had lower leukocyte count (P = .003), lymphocyte count (P = .030), and higher prevalence (P = .012) of elevated C-reactive protein (CRP) at admission. NRD patients had a lower prevalence of reticulations (P = .034) on baseline CT (CT1, performed within 2 days before admission) and a longer duration between symptom onset and the time of CT2 (P < .01). There was no significant difference in hospital stay or fibrotic change on CT4 (follow-up CT scan performed 4 weeks after discharge) between 2 groups. Shorter duration between symptom onset and CT2 time (odds ratio [OR], 0.436; 95% confidence interval: 0.233-0.816; P < .01) and lower leukocyte count in baseline evaluation (OR, 0.316; 95% CI: 0.116-0.859; P < .05) were associated with increased odds of radiological deterioration on CT image during hospitalization.For moderate COVID-19 patients, the value of routinely performed CT during the treatment is limited. We recommend avoiding using CT as a routine monitor in moderate COVID-19 patients.


Assuntos
COVID-19/diagnóstico por imagem , Progressão da Doença , Tomografia Computadorizada por Raios X/estatística & dados numéricos , Adolescente , Adulto , Idoso , Proteína C-Reativa/análise , Deterioração Clínica , Feminino , Humanos , Tempo de Internação , Contagem de Leucócitos , Contagem de Linfócitos , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Estudos Retrospectivos , Fatores de Risco , SARS-CoV-2 , Índice de Gravidade de Doença , Tempo para o Tratamento , Adulto Jovem
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