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1.
Small ; 20(27): e2310250, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38295142

RESUMO

The commercialization of rechargeable Zn-air batteries (ZABs) relies on the material innovation to accelerate the sluggish oxygen electrocatalysis kinetics. Due to the differentiated mechanisms of reverse processes, i.e., oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), rationally integrating dual sites for bifunctional oxygen electrocatalysis is prerequisite yet remains challenging. Herein, multicomponent synergistic active sites within highly graphitic carbon substrate are exquisitely constructed, which is accomplished by fluorine (F) modulation strategy. The incorporation of F dopants facilitates pyridinic N formation for anchoring single metal sites, thus guaranteeing the coexistence of sufficient M-Nx sites and metal nanoparticles toward bifunctional oxygen electrocatalysis. As a result, the optimal catalyst, denoted as F NH2-FeNi-800, outperforms commercial Pt/C+RuO2 with smaller gap between Ej = 10 and E1/2 (ΔE) of 0.63 V (vs 0.7 V for Pt/C+RuO2), demonstrating its superior bifunctionality. Beyond that, its superiority is validated in homemade rechargeable ZABs. ZABs assembled using F NH2-FeNi-800 as the air cathode delivers higher peak power density (123.8 mW cm-2) and long-cycle lifetime (over 660 cycles) in comparison with Pt/C@RuO2 (68.8 mW cm-2; 300 cycles). The finding not only affords a highly promising oxygen electrocatalyst, but also opens an avenue to constructing multifunctional active sites for heterogeneous catalysts.

2.
Angew Chem Int Ed Engl ; 63(7): e202315119, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38129317

RESUMO

Alleviating the degradation issue of Pt based alloy catalysts, thereby simultaneously achieving high mass activity and high durability in proton exchange membrane fuel cells (PEMFCs), is highly challenging. Herein, we provide a new paradigm to address this issue via delaying the place exchange between adsorbed oxygen species and surface Pt atoms, thereby inhibiting Pt dissolution, through introducing rare earth bonded subsurface oxygen atoms. We have succeeded in introducing Gd-O dipoles into Pt3 Ni via a high temperature entropy-driven process, with direct spectral evidence attained from both soft and hard X-ray absorption spectroscopies. The higher rated power of 0.93 W cm-2 and superior current density of 562.2 mA cm-2 at 0.8 V than DOE target for heavy-duty vehicles in H2 -air mode suggest the great potential of Gd-O-Pt3 Ni towards practical application in heavy-duty transportation. Moreover, the mass activity retention (1.04 A mgPt -1 ) after 40 k cycles accelerated durability tests is even 2.4 times of the initial mass activity goal for DOE 2025 (0.44 A mgPt -1 ), due to the weakened Pt-Oads bond interaction and the delayed place exchange process, via repulsive forces between surface O atoms and those in the sublayer. This work addresses the critical roadblocks to the widespread adoption of PEMFCs.

3.
Chemistry ; 29(12): e202203180, 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36378121

RESUMO

Electrochemical production of hydrogen peroxide (H2 O2 ) via two-electron oxygen reduction reaction (ORR) process is emerging as a promising alternative method to the conventional anthraquinone process. To realize high-efficiency H2 O2 electrosynthesis, robust and low cost electrocatalysts have been intensively pursued, among which Co-based catalysts attract particular research interests due to the earth-abundance and high selectivity. Here, we provide a comprehensive review on the advancement of Co-based electrocatalyst for H2 O2 electroproduction. The fundamental chemistry of 2-electron ORR is discussed firstly for guiding the rational design of electrocatalysts. Subsequently, the development of Co-based electrocatalysts involving nanoparticles, compounds and single atom catalysts is summarized with the focus on active site identification, structure regulation and mechanism understanding. Moreover, the current challenges and future directions of the Co-based electrocatalysts are briefly summarized in this review.

4.
Eur Radiol ; 33(8): 5814-5824, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37171486

RESUMO

OBJECTIVES: To develop a fusion model based on clinicopathological factors and MRI radiomics features for the prediction of recurrence risk in patients with endometrial cancer (EC). METHODS: A total of 421 patients with histopathologically proved EC (101 recurrence vs. 320 non-recurrence EC) from four medical centers were included in this retrospective study, and were divided into the training (n = 235), internal validation (n = 102), and external validation (n = 84) cohorts. In total, 1702 radiomics features were respectively extracted from areas with different extensions for each patient. The extreme gradient boosting (XGBoost) classifier was applied to establish the clinicopathological model (CM), radiomics model (RM), and fusion model (FM). The performance of the established models was assessed by the discrimination, calibration, and clinical utility. Kaplan-Meier analysis was conducted to further determine the prognostic value of the models by evaluating the differences in recurrence-free survival (RFS) between the high- and low-risk patients of recurrence. RESULTS: The FMs showed better performance compared with the models based on clinicopathological or radiomics features alone but with a reduced tendency when the peritumoral area (PA) was extended. The FM based on intratumoral area (IA) [FM (IA)] had the optimal performance in predicting the recurrence risk in terms of the ROC, calibration curve, and decision curve analysis. Kaplan-Meier survival curves showed that high-risk patients of recurrence defined by FM (IA) had a worse RFS than low-risk ones of recurrence. CONCLUSIONS: The FM integrating intratumoral radiomics features and clinicopathological factors could be a valuable predictor for the recurrence risk of EC patients. CLINICAL RELEVANCE STATEMENT: An accurate prediction based on our developed FM (IA) for the recurrence risk of EC could facilitate making an individualized therapeutic decision and help avoid under- or over-treatment, therefore improving the prognosis of patients. KEY POINTS: • The fusion model combined clinicopathological factors and radiomics features exhibits the highest performance compared with the clinicopathological model and radiomics model. • Although higher values of area under the curve were observed for all fusion models, the performance tended to decrease with the extension of the peritumoral region. • Identifying patients with different risks of recurrence, the developed models can be used to facilitate individualized management.


Assuntos
Neoplasias do Endométrio , Imageamento por Ressonância Magnética , Humanos , Feminino , Estudos Retrospectivos , Prognóstico , Estimativa de Kaplan-Meier , Neoplasias do Endométrio/diagnóstico por imagem
5.
J Am Chem Soc ; 144(22): 9661-9671, 2022 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-35622935

RESUMO

Developing highly active, selective, and stable electrocatalysts for the carbon dioxide reduction reaction (CO2RR) is crucial to establish a CO2 conversion system for industrial implementation and, therefore, to realize an artificially closed carbon loop. This can only be achieved through the rational material design based upon the knowledge of the operational active site at the molecular scale. Enlightened by theoretical screening, herein, we for the first time manipulate a novel Ni-Cu atomic pair configuration toward improved CO2RR performance. Systematic characterizations and theoretical modeling reveal that the secondary Cu metal incorporation positively shifts the Ni 3d orbital energy to the Fermi level and thus accelerates the rate-determining step, *COOH formation. In addition, the intrinsic inactivity of Cu toward the competing hydrogen evolution reaction causes a considerable reaction barrier for water dissociation on the Ni-Cu moiety. Due to these attributes, the as-developed Ni/Cu-N-C catalyst exhibits excellent catalytic activity and selectivity, with a record-high turnover frequency of 20,695 h-1 at -0.6 V (vs RHE) and a maximum Faradaic efficiency of 97.7% for CO production. Furthermore, the dynamic structure evolution monitored by operando X-ray absorption fine-structure spectroscopy unveils the interaction between the Ni center and CO2 molecules and the synergistic effect of the Ni-Cu atomic pair on CO2RR activity.

6.
Acta Radiol ; 63(10): 1415-1424, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34382429

RESUMO

BACKGROUND: Differentiating adenosquamous carcinoma (ASC) and adenocarcinoma (AC) from squamous cell carcinoma (SCC) precisely is crucial for treatment strategy and prognosis prediction in patients with cervical cancer (CC). PURPOSE: To differentiate ASC and AC from SCC in patients with CC using the apparent diffusion coefficient (ADC) histogram analysis. MATERIAL AND METHODS: A total of 118 patients with histologically diagnosed ASC, AC, and SCC were included. The ADC histogram parameters were extracted from ADC maps. Receiver operating characteristic analysis was performed to evaluate the diagnostic performance of each ADC histogram parameter in differentiating the subtypes of CC. The predictors for histologic subtypes were further selected using univariate and multivariate logistic regression analyses. RESULTS: The ADCmean, ADCmax, ADCP10, ADCP25, ADCP75, ADCP90, ADCmedian, and ADCmode of the ASC were significantly lower than those of the AC; and ADCkurtosis and ADCskewness of the ASC were lower than those of the SCC. The ADCmean, ADCmax, ADCP10, ADCP25, ADCP75, ADCP90, ADCmedian, and ADCmode of AC were significantly higher than those of the SCC. The ADCP10 and ADCP10 + diameter yielded the AUCs of 0.753 and 0.778 in differentiating ASC from AC. The ADCmedian and ADCmedian + diameter yielded the AUCs of 0.807 and 0.838 in differentiating AC from SCC. The ADCskewness yielded the AUC of 0.713 in differentiating ASC from SCC. CONCLUSION: The ADCP10 and ADCP10 + diameter, ADCmedian, and ADCmedian + diameter performed well in differentiating ASC from AC and AC from SCC, respectively. However, ADCskewness exhibited a limited ability in differentiating ASC from SCC.


Assuntos
Adenocarcinoma , Carcinoma Adenoescamoso , Carcinoma de Células Escamosas , Neoplasias do Colo do Útero , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Carcinoma Adenoescamoso/diagnóstico por imagem , Carcinoma Adenoescamoso/patologia , Carcinoma de Células Escamosas/diagnóstico por imagem , Carcinoma de Células Escamosas/patologia , Imagem de Difusão por Ressonância Magnética , Feminino , Humanos , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia
7.
J Magn Reson Imaging ; 52(3): 885-896, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32096586

RESUMO

BACKGROUND: Lymph node metastasis (LNM) is a critical risk factor affecting treatment strategy and prognosis in patients with early-stage cervical cancer. PURPOSE: To establish a multiparametric MRI (mpMRI)-based radiomics nomogram for preoperatively predicting LNM status. STUDY TYPE: Retrospective. POPULATION: Among 233 consecutive patients, 155 patients were randomly allocated to the primary cohort and 78 patients to the validation cohort. FIELD STRENGTH: Radiomic features were extracted from a 1.5T mpMRI scan (T1 -weighted imaging [T1 WI], fat-saturated T2 -weighted imaging [FS-T2 WI], contrast-enhanced [CE], diffusion-weighted imaging [DWI], and apparent diffusion coefficient [ADC] maps). ASSESSMENT: The performance of the nomogram was assessed with respect to its calibration, discrimination, and clinical usefulness. The area under the receiver operating characteristics curve (ROC AUC), accuracy, sensitivity, and specificity were also calculated. STATISTICAL TESTS: The least absolute shrinkage and selection operator (LASSO) method was used for dimension reduction, feature selection, and radiomics signature building. Multivariable logistic regression analysis was used to develop the radiomics nomogram. An independent sample t-test and chi-squared test were used to compare the differences in continuous and categorical variables, respectively. RESULTS: The radiomic signature allowed a good discrimination between the LNM and non-LNM groups, with a C-index of 0.856 (95% confidence interval [CI], 0.794-0.918) in the primary cohort and 0.883 (95% CI, 0.809-0.957) in the validation cohort. Additionally, the radiomics nomogram also had a good discriminating performance and yielded good calibration both in the primary and validation cohorts (C-index, 0.882 [95% CI, 0.827-0.937], C-index, 0.893 [95% CI, 0.822-0.964], respectively). Decision curve analysis demonstrated that the radiomics nomogram was clinically useful. DATA CONCLUSION: A radiomics nomogram was developed by incorporating the radiomics signature with the MRI-reported LN status and FIGO stage. This nomogram might be used to facilitate the individualized prediction of LNM in patients with early-stage cervical cancer. LEVEL OF EVIDENCE: 3 TECHNICAL EFFICACY STAGE: 2 J. Magn. Reson. Imaging 2020;52:885-896.


Assuntos
Imageamento por Ressonância Magnética Multiparamétrica , Neoplasias do Colo do Útero , Feminino , Humanos , Linfonodos/diagnóstico por imagem , Metástase Linfática/diagnóstico por imagem , Imageamento por Ressonância Magnética , Nomogramas , Estudos Retrospectivos , Neoplasias do Colo do Útero/diagnóstico por imagem
8.
Eur Radiol ; 30(3): 1405-1418, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31776741

RESUMO

OBJECTIVES: This study aims to determine the diagnostic performance of conventional magnetic resonance imaging (MRI) in assessing the distance between the tumor and the internal os, stromal infiltration, lymph node metastasis, and parametrial invasion in patients with cervical cancer. METHODS: A systematic English-language literature search of conventional MRI in the evaluation of human cervical cancer was performed in the PubMed, Cochrane Library, Embase, and Web of Science databases from 1995 to 2018. The pooled sensitivity, specificity, diagnostic odds ratio (DOR), and positive and negative likelihood ratios (PLR and NLR) of all studies were calculated. The results were then plotted in a hierarchical summary receiver operating characteristic (HSROC) plot, and meta-regression and subgroup analyses of the parametrial invasion were also performed. RESULTS: The pooled sensitivity, specificity, DOR, PLR, and NLR were 86%, 97%, 167.91, 24.74, and 0.15, respectively, in evaluating the internal os involvement (6 studies, 454 patients); 87%, 91%, 73.41, 10.22, and 0.14, respectively, in evaluating the stromal infiltration (11 studies, 672 patients); 51%, 89%, 8.63, 4.72, and 0.55, respectively, in evaluating the lymph node metastasis (15 studies, 997 patients); and 75%, 92%, 34.01, 9.38, and 0.28, respectively, in evaluating the parametrial invasion (19 studies, 1748 patients). The meta-regression of the parametrial invasion showed that the application of contrast enhancement was a significant factor affected the heterogeneity (p = 0.039). CONCLUSIONS: Conventional MRI can accurately evaluate the distance between the tumor and the internal os, as well as stromal infiltration, and performs well in diagnosing the parametrial invasion. However, this method exhibited a limited ability in diagnosing the lymph node metastasis. KEY POINTS: • MRI can help clinicians to accurately assess the distance between the tumor and the internal os, stromal infiltration, and parametrial invasion in patients with uterine cervical neoplasms. • MRI exhibits a limited ability in diagnosing the lymph node metastasis. • Management of patients with uterine cervical neoplasms becomes more appropriate.


Assuntos
Linfonodos/diagnóstico por imagem , Imageamento por Ressonância Magnética , Peritônio/diagnóstico por imagem , Neoplasias do Colo do Útero/diagnóstico por imagem , Feminino , Humanos , Excisão de Linfonodo , Linfonodos/patologia , Metástase Linfática , Invasividade Neoplásica , Estadiamento de Neoplasias , Razão de Chances , Seleção de Pacientes , Peritônio/patologia , Prognóstico , Curva ROC , Sensibilidade e Especificidade , Traquelectomia , Neoplasias do Colo do Útero/patologia , Neoplasias do Colo do Útero/cirurgia
9.
J Am Chem Soc ; 141(50): 19800-19806, 2019 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-31763837

RESUMO

Emerging as a new frontier in heterogeneous catalysis, single-atom site catalysts (SSCs) have sparked enormous attention and bring about new opportunities to oxygen reduction electrocatalysis. Despite considerable progress achieved recently, most of the reported SSCs suffer from either insufficient activity or unsatisfactory stability, which severely retards their practical application. Here, we demonstrate a novel Ru-SSC with appropriate adsorption free energy of OH* (ΔGOH*) to confer excellent activity and low Fenton reactivity to maintain long-term stability. The as-developed Ru-SSC exhibits encouraging oxygen reduction reaction turnover frequency of 4.99 e- s-1 sites-1, far exceeding the state-of-the-art Fe-SSC counterpart (0.816 e- s-1 sites-1), as a result of Ru energy level regulation via spontaneous OH binding. Furthermore, Ru-SSC exhibits greatly suppressed Fenton reactivity, with restrained generation of reactive oxygen species directly observed, thus endowing the Ru-SSC with much more superior stability (only 17 mV negative shift after 20 000 cycles) than the Fe-SSC counterpart (31 mV). The practical application of Ru-SSC is further validated by its excellent activity and stability in a real fuel cell device.

10.
J Am Chem Soc ; 141(44): 17763-17770, 2019 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-31603677

RESUMO

Great enthusiasm in single-atom catalysts (SACs) for the oxygen reduction reaction (ORR) has been aroused by the discovery of M-NX as a promising ORR catalysis center. However, the performance of SACs lags far behind that of state-of-the-art Pt due to the unsatisfactory adsorption-desorption behaviors of the reported catalytic centers. To address this issue, rational manipulation of the active site configuration toward a well-managed energy level and geometric structure is urgently desired, yet still remains a challenge. Herein, we report a novel strategy to accomplish this task through the construction of an Fe-Co dual-atom centered site. A spontaneously absorbed electron-withdrawing OH ligand was proposed to act proactively as an energy level modifier to empower easy intermediate desorption, while the triangular Fe-Co-OH coordination facilitates O-O bond scission. Benefiting from these attributes, the as-constructed FeCoN5-OH site enables an ORR onset potential and half-wave potential of up to 1.02 and 0.86 V (vs RHE), respectively, with an intrinsic activity over 20 times higher than the single-atom FeN4 site. Our finding not only opens up a novel strategy to tailor the electronic structure of an atomic site toward boosted activity but also provides new insights into the fundamental understanding of diatomic sites for ORR electrocatalysis.

11.
Small ; 15(44): e1903610, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31512394

RESUMO

Flexible Zn-air batteries have recently emerged as one of the key energy storage systems of wearable/portable electronic devices, drawing enormous attention due to the high theoretical energy density, flat working voltage, low cost, and excellent safety. However, the majority of the previously reported flexible Zn-air batteries encounter problems such as sluggish oxygen reaction kinetics, inferior long-term durability, and poor flexibility induced by the rigid nature of the air cathode, all of which severely hinder their practical applications. Herein, a defect-enriched nitrogen doped-graphene quantum dots (N-GQDs) engineered 3D NiCo2 S4 nanoarray is developed by a facile chemical sulfuration and subsequent electrophoretic deposition process. The as-fabricated N-GQDs/NiCo2 S4 nanoarray grown on carbon cloth as a flexible air cathode exhibits superior electrocatalytic activities toward both oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), outstanding cycle stability (200 h at 20 mA cm-2 ), and excellent mechanical flexibility (without observable decay under various bending angles). These impressive enhancements in electrocatalytic performance are mainly attributed to bifunctional active sites within the N-GQDs/NiCo2 S4 catalyst and synergistic coupling effects between N-GQDs and NiCo2 S4 . Density functional theory analysis further reveals that stronger OOH* dissociation adsorption at the interface between N-GQDs and NiCo2 S4 lowers the overpotential of both ORR and OER.

12.
Respiration ; 97(2): 168-172, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30408775

RESUMO

Primary mucosa-associated lymphoid tissue (MALT) lymphoma of the trachea is very rare and is easily misdiagnosed as a bronchogenic carcinoma or benign tracheal tumor. Here, we report a clinical case where a new clinical approach involving a water-jet hybrid knife was employed in the diagnosis and treatment of primary tracheal MALT lymphoma.


Assuntos
Dissecação/instrumentação , Eletrocirurgia/instrumentação , Linfoma de Células B/cirurgia , Mucosa Respiratória/cirurgia , Neoplasias da Traqueia/cirurgia , Idoso , Humanos , Masculino , Cirurgia Endoscópica por Orifício Natural/instrumentação , Água
13.
Angew Chem Int Ed Engl ; 58(28): 9640-9645, 2019 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-31120620

RESUMO

Combining the advantages of homogeneous and heterogeneous catalysts, single-atom catalysts (SACs) are bringing new opportunities to revolutionize ORR catalysis in terms of cost, activity and durability. However, the lack of high-performance SACs as well as the fundamental understanding of their unique catalytic mechanisms call for serious advances in this field. Herein, for the first time, we develop an Ir-N-C single-atom catalyst (Ir-SAC) which mimics homogeneous iridium porphyrins for high-efficiency ORR catalysis. In accordance with theoretical predictions, the as-developed Ir-SAC exhibits orders of magnitude higher ORR activity than iridium nanoparticles with a record-high turnover frequency (TOF) of 24.3 e- site-1 s-1 at 0.85 V vs. RHE) and an impressive mass activity of 12.2 A mg-1 Ir , which far outperforms the previously reported SACs and commercial Pt/C. Atomic structural characterizations and density functional theory calculations reveal that the high activity of Ir-SAC is attributed to the moderate adsorption energy of reaction intermediates on the mononuclear iridium ion coordinated with four nitrogen atom sites.

14.
J BUON ; 23(3): 776-781, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30003751

RESUMO

PURPOSE: The purpose of this study was to investigate the expression of long-chain non-coding RNA (lncRNA) SNHG7 in bladder cancer tissues and cell lines, and to explore its impact on bladder cancer cell proliferation, apoptosis and invasion processes. METHODS: Bladder cancer tissues and near-cancer tissues were collected. The expression of lncRNA-SNHG7 in tissues and cell lines was detected by real-time PCR (RT-PCR). The expression of lncRNA-SNHG7 was downregulated by RNA interference (siRNA) as detected by RT-PCR that was used to detect the interference efficiency. CCK-8, flow cytometry and Transwell assays were used to evaluate the effect of lncRNASNHG7 on the proliferation, apoptosis and invasion capability of bladder cancer cells. The downregulation effect of lncRNA-SNHG7 on Epithelial-Mesenchymal Transition (EMT) related markers was tested by westernblot. RESULTS: lncRNA-SNHG7 was upregulated in bladder cancer cell lines. After the expression of lncRNA-SNHG7 was downregulated, the proliferation of bladder cancer cells was decreased, the apoptosis was increased, and the invasion ability of cells was decreased. The expression of E-cadherin was increased, but the expression of N-cadherin, vimentin and snail were decreased. Increased expression of lncRNASNHG7 in cancer tissues was significantly related to tumor size, metastasis and stage. CONCLUSIONS: This study showed that lncRNA -SNHG7 is overexpressed in bladder cancer tissues and cells. Downregulation of lncRNA-SNHG7 can inhibit the proliferation of bladder cancer cells and promote apoptosis, as well as inhibit cell invasion, which provides a potential molecular target for future tumor targeted therapy.


Assuntos
Apoptose/genética , Proliferação de Células/genética , Invasividade Neoplásica/genética , RNA Longo não Codificante/genética , Neoplasias da Bexiga Urinária/genética , Caderinas/genética , Linhagem Celular Tumoral , Movimento Celular/genética , Regulação para Baixo/genética , Transição Epitelial-Mesenquimal/genética , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Interferência de RNA/fisiologia , RNA Interferente Pequeno/genética , Regulação para Cima/genética , Bexiga Urinária/patologia , Neoplasias da Bexiga Urinária/patologia
15.
ACS Appl Mater Interfaces ; 16(24): 31747-31755, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38839057

RESUMO

Phase transitions play an important role in tuning the physical properties of two-dimensional (2D) materials as well as developing their high-performance device applications. Here, we reported the observation of a phase transition in few-layered MoTe2 flakes by the irradiation of gallium (Ga+) ions using a focused ion beam (FIB) system. The semiconducting 2H phase of MoTe2 can be controllably converted to the metallic 1T'-like phase via Te defect engineering during irradiations. By taking advantage of the nanometer-sized Ga+ ion probe proved by FIB, in-plane 1T'-2H homojunctions of MoTe2 at submicrometer scale can be fabricated. Furthermore, we demonstrate the improvement of device performance (on-state current over 2 orders of magnitude higher) in MoTe2 transistors using the patterned 1T'-like phase regions as contact electrodes. Our study provides a new strategy to drive the phase transitions in MoTe2, tune their properties, and develop high-performance devices, which also extends the applications of FIB technology in 2D materials and their devices.

16.
Abdom Radiol (NY) ; 49(5): 1557-1568, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38441631

RESUMO

OBJECTIVE: To developed a magnetic resonance imaging (MRI) radiomics nomogram to identify adenocarcinoma at the cervix-corpus junction originating from the endometrium or cervix in order to better guide clinical treatment. METHODS: Between February 2011 and September 2021, the clinicopathological data and MRI in 143 patients with histopathologically confirmed cervical adenocarcinoma (CAC, n = 86) and endometrioid adenocarcinoma (EAC, n = 57) were retrospectively analyzed at the cervix-corpus junction. Radiomics features were extracted from fat-suppressed T2-weighted imaging (FS-T2WI), diffusion-weighted imaging (DWI), apparent diffusion coefficient (ADC) maps, and delayed phase contrast-enhanced T1-weighted imaging (CE-T1WI) sequences. A radiomics nomogram was developed integrating radscore with independent clinical risk factors. The area under the curve (AUC) was used to evaluate the diagnostic efficacy of the radscore, nomogram and two different experienced radiologists in differentiating CAC from EAC at the cervix-corpus junction, and Delong test was applied to compare the differences of their diagnostic performance. RESULTS: In the training cohort, the AUC was 0.93 for radscore; 0.97 for radiomics nomograms; 0.85 and 0.86 for radiologists 1 and 2, respectively. Delong test showed that the differential efficacy of nomogram was significant better than those of radiologists in the training cohort (both P < 0.05). CONCLUSIONS: The nomogram based on radscore and clinical risk factors could better differentiate CAC from EAC at the cervix-corpus junction than radiologists, and preoperatively and non-invasively identify the origin of adenocarcinoma at the cervix-corpus junction, which facilitates clinicians to make individualized treatment decision.


Assuntos
Adenocarcinoma , Carcinoma Endometrioide , Neoplasias do Endométrio , Imageamento por Ressonância Magnética Multiparamétrica , Nomogramas , Neoplasias do Colo do Útero , Humanos , Feminino , Neoplasias do Colo do Útero/diagnóstico por imagem , Neoplasias do Colo do Útero/patologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Adenocarcinoma/diagnóstico por imagem , Adenocarcinoma/patologia , Carcinoma Endometrioide/diagnóstico por imagem , Carcinoma Endometrioide/patologia , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/patologia , Adulto , Imageamento por Ressonância Magnética Multiparamétrica/métodos , Idoso , Diagnóstico Diferencial , Colo do Útero/diagnóstico por imagem , Colo do Útero/patologia , Meios de Contraste , Radiômica
17.
Nat Commun ; 15(1): 4219, 2024 May 17.
Artigo em Inglês | MEDLINE | ID: mdl-38760340

RESUMO

The limited durability of metal-nitrogen-carbon electrocatalysts severely restricts their applicability for the oxygen reduction reaction in proton exchange membrane fuel cells. In this study, we employ the chemical vapor modification method to alter the configuration of active sites from FeN4 to the stable monosymmetric FeN2+N'2, along with enhancing the degree of graphitization in the carbon substrate. This improvement effectively addresses the challenges associated with Fe active center leaching caused by N-group protonation and free radicals attack due to the 2-electron oxygen reduction reaction. The electrocatalyst with neoteric active site exhibited excellent durability. During accelerated aging test, the electrocatalyst exhibited negligible decline in its half-wave potential even after undergoing 200,000 potential cycles. Furthermore, when subjected to operational conditions representative of fuel cell systems, the electrocatalyst displayed remarkable durability, sustaining stable performance for a duration exceeding 248 h. The significant improvement in durability provides highly valuable insights for the practical application of metal-nitrogen-carbon electrocatalysts.

18.
Genes (Basel) ; 14(7)2023 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-37510389

RESUMO

Despite the worldwide distribution and rich diversity of the infraorder Bibionomorpha in Diptera, the characteristics of mitochondrial genomes (mitogenomes) are still little-known, and the phylogenetics and evolution of the infraorder remains controversial. In the present study, we report complete and annotated mitogenome sequences of Penthetria simplioipes and Plecia hardyi representing Bibionidae. This is the first report of the complete mitogenomes for the superfamily Bibionoidea. There are 37 genes in each of the complete mitogenomes of all 20 studied species from eight families of four superfamilies within infraorder Bibionomorpha. The Ka/Ks analysis suggests that all 13 PCGs have undergone purifying selection. The gene rearrangement events exist in some families (Keroplatidae, Sciaridae, and Cecidomyiidae) but not in Mycetophilidae in Sciaroidea and also in Scatopsoidea, Anisopodoidea, and Bibionoidea, which suggests that these rearrangement events are derived in the late period in the evolution of the Bibionomorpha. The phylogenetic analysis suggests the phylogenetic relationships of Scatopsoidea + (Anisopodoidea + (Bibionoidea + Sciaroidea)) in Bibionomorpha. The divergence time analysis suggests that Bibionomorpha originated in the Triassic, Scatopsoidea and Anisopodoidea in the late Triassic, Bibionoidea in the Jurassic, and Sciaroidea in the Jurassic to the Cretaceous. The work lays a base for the study of mitogenomes in Bibionomorpha but further work and broader taxon sampling are necessary for a better understanding of the phylogenetics and evolution of the infraorder.


Assuntos
Dípteros , Genoma Mitocondrial , Animais , Dípteros/genética , Filogenia , Genoma Mitocondrial/genética , Nematóceros/genética
19.
Quant Imaging Med Surg ; 13(1): 108-120, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36620141

RESUMO

Background: Microsatellite instability (MSI) status is an important indicator for screening patients with endometrial cancer (EC) who have potential Lynch syndrome (LS) and may benefit from immunotherapy. This study aimed to develop a magnetic resonance imaging (MRI)-based radiomics nomogram for the prediction of MSI status in EC. Methods: A total of 296 patients with histopathologically diagnosed EC were enrolled, and their MSI status was determined using immunohistochemical (IHC) analysis. Patients were randomly divided into the training cohort (n=236) and the validation cohort (n=60) at a ratio of 8:2. To predict the MSI status in EC, the tumor radiomics features were extracted from T2-weighted images and contrast-enhanced T1-weighted images, which in turn were selected using one-way analysis of variance (ANOVA) and the least absolute shrinkage and selection operator (LASSO) algorithm to build the radiomics signature (radiomics score; radscore) model. Five clinicopathologic characteristics were used to construct a clinicopathologic model. Finally, the nomogram model combining radscore and clinicopathologic characteristics was constructed. The performance of the three models was evaluated using receiver operating characteristic (ROC), calibration, and decision curve analyses (DCA). Results: Totals of 21 radiomics features and five clinicopathologic characteristics were selected to develop the radscore and clinicopathological models. The radscore and clinicopathologic models achieved an area under the curve (AUC) of 0.752 and 0.600, respectively, in the training cohort; and of 0.723 and 0.615, respectively, in the validation cohort. The radiomics nomogram model showed improved discrimination efficiency compared with the radscore and clinicopathologic models, with an AUC of 0.773 and 0.740 in the training and validation cohorts, respectively. The calibration curve analysis and DCA showed favorable calibration and clinical utility of the nomogram model. Conclusions: The nomogram incorporating MRI-based radiomics features and clinicopathologic characteristics could be a potential tool for the prediction of MSI status in EC.

20.
Br J Radiol ; 96(1151): 20221063, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37660398

RESUMO

OBJECTIVES: Preoperative identification of POLE mutation status would help tailor the surgical procedure and adjuvant treatment strategy. This study aimed to explore the feasibility of developing a radiomics model to pre-operatively predict the pathogenic POLE mutation status in patients with EC. METHODS: The retrospective study involved 138 patients with histopathologically confirmed EC (35 POLE-mutant vs 103 non-POLE-mutant). After selecting relevant features with a series of steps, three radiomics signatures were built based on axial fat-saturation T2WI, DWI, and CE-T1WI images, respectively. Then, two radiomics models which integrated features from T2WI + DWI and T2WI + DWI+CE-T1WI were further developed using multivariate logistic regression. The performance of the radiomics model was evaluated from discrimination, calibration, and clinical utility aspects. RESULTS: Among all the models, radiomics model2 (RM2), which integrated features from all three sequences, showed the best performance, with AUCs of 0.885 (95%CI: 0.828-0.942) and 0.810 (95%CI: 0.653-0.967) in the training and validation cohorts, respectively. The net reclassification index (NRI) and integrated discrimination improvement (IDI) analyses indicated that RM2 had improvement in predicting POLE mutation status when compared with the single-sequence-based signatures and the radiomics model1 (RM1). The calibration curve, decision curve analysis, and clinical impact curve suggested favourable calibration and clinical utility of RM2. CONCLUSIONS: The RM2, fusing features from three sequences, could be a potential tool for the non-invasive preoperative identification of patients with POLE-mutant EC, which is helpful for developing individualized therapeutic strategies. ADVANCES IN KNOWLEDGE: This study developed a potential surrogate of POLE sequencing, which is cost-efficient and non-invasive.


Assuntos
Neoplasias do Endométrio , Humanos , Feminino , Estudos Retrospectivos , Neoplasias do Endométrio/diagnóstico por imagem , Neoplasias do Endométrio/genética , Área Sob a Curva , Imageamento por Ressonância Magnética , Mutação
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