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1.
Small ; : e2400155, 2024 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-38644332

RESUMO

Nanopatterning driven by electrohydrodynamic (EHD) instability can aid in the resolution of the drawbacks inherent in conventional imprinting or other molding methods. This is because EHD force negates the requirement of physical contact and is easily tuned. However, its potential has not examined owing to the limited size of the pattern replica (several to tens of micrometers). Thus, this study proposes a new route for large-area patterning through high-speed evolution of EHD-driven pattern growth along the in-plane axis. Through the acceleration of the in-plane growth, while selectively controlling a specific edge growth, the pattern replica area can be extended from the micro- to centimeter scale with high fidelity. Moreover, even in the case of nonuniform contact mode, the proposed rapid in-plane growth mode facilitates uniform large-scale replication, which is not possible in conventional imprinting or other molding methods.

2.
ACS Nano ; 17(22): 22456-22466, 2023 Nov 28.
Artigo em Inglês | MEDLINE | ID: mdl-37939012

RESUMO

Despite the prospects of electrohydrodynamic instability patterning (EHIP), poor process parameter controllability is a significant challenge in uniform large-scale nanopatterning. Herein, we introduce a EHIP process using an ultrahigh electric field (>108 V/m) to effectively accelerate the pattern growth evolution. Owing to the strong dependence on a temporal parameter (1/τm) of the field strength, our method not only reduces the completion time of pattern growth but also overcomes critical parametric restrictions on the pattern replication, thereby enhancing the replicated pattern quality in three dimensions. The pattern can be uniformly replicated over the entire film surface even without a perfectly uniform air gap, which has been severely difficult in the conventional method. To further demonstrate how straightforward yet versatile our approach is, we applied our EHIP approach to successfully replicate the densely packed nanostructures of cicada wings.

3.
ACS Appl Mater Interfaces ; 13(23): 27575-27585, 2021 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-34085809

RESUMO

The outcomes of the study of plant surfaces, such as rice leaves or bamboo leaves, have led to extensive efforts being devoted to fabricating anisotropic arrays of micro/nanoscale features for exploring anisotropic droplet spreading. Nonetheless, precise engineering of the density and continuity of three-phase contact lines for anisotropic wetting remains a significant challenge without resorting to chemical modifications and costly procedures. In this work, we investigated secondary electrohydrodynamic instability in polymer films for producing secondary nanosized patterns between the micrometer-sized grooves by controlling the timescale parameter, 1/τm (>10-4 s-1). We experimentally demonstrated facile morphological control of anisotropic wettability without the use of any chemical modifications. Thus, anisotropic hydrophilic surfaces fabricated by the secondary phase instability of polymer films are advantageous for both droplet condensation and removal, thereby outperforming the water collection efficiency of conventional (isotropic) hydrophilic surfaces in water harvesting applications (∼200 mg·cm-2·h-1) with excellent durability.

4.
RSC Adv ; 11(30): 18152-18161, 2021 May 19.
Artigo em Inglês | MEDLINE | ID: mdl-35480914

RESUMO

Electrohydrodynamic (EHD) instability patterning exhibits substantial potential for application as a next-generation lithographic technique; nevertheless, its development continues to be hindered by the lack of process parameter controllability, especially when replicating sub-microscale pattern features. In this paper, a new parametric guide is introduced. It features an expanded range of valid parameters by increasing the pattern growth velocity, thereby facilitating reproducible EHD-driven patterning for perfect nanopattern replication. Compared with conventional EHD-driven patterning, the rapid patterning approach not only shortens the patterning time but also exhibits enhanced scalability for replicating small and geometrically diverse features. Numerical analyses and simulations are performed to elucidate the interplay between the pattern growth velocity, fidelity of the replicated features, and boundary between the domains of suitable and unsuitable parametric conditions in EHD-driven patterning. The developed rapid route facilitates nanopattern replication using EHD instability with a wide range of suitable parameters and further opens up many opportunities for device applications using tailor-made nanostructures in an effective and straightforward manner.

5.
Hepatol Int ; 14(5): 690-700, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32623632

RESUMO

BACKGROUND AND AIMS: COVID-19 is a dominant pulmonary disease, with multisystem involvement, depending upon comorbidities. Its profile in patients with pre-existing chronic liver disease (CLD) is largely unknown. We studied the liver injury patterns of SARS-Cov-2 in CLD patients, with or without cirrhosis. METHODS: Data was collected from 13 Asian countries on patients with CLD, known or newly diagnosed, with confirmed COVID-19. RESULTS: Altogether, 228 patients [185 CLD without cirrhosis and 43 with cirrhosis] were enrolled, with comorbidities in nearly 80%. Metabolism associated fatty liver disease (113, 61%) and viral etiology (26, 60%) were common. In CLD without cirrhosis, diabetes [57.7% vs 39.7%, OR = 2.1 (1.1-3.7), p = 0.01] and in cirrhotics, obesity, [64.3% vs. 17.2%, OR = 8.1 (1.9-38.8), p = 0.002] predisposed more to liver injury than those without these. Forty three percent of CLD without cirrhosis presented as acute liver injury and 20% cirrhotics presented with either acute-on-chronic liver failure [5 (11.6%)] or acute decompensation [4 (9%)]. Liver related complications increased (p < 0.05) with stage of liver disease; a Child-Turcotte Pugh score of 9 or more at presentation predicted high mortality [AUROC 0.94, HR = 19.2 (95 CI 2.3-163.3), p < 0.001, sensitivity 85.7% and specificity 94.4%). In decompensated cirrhotics, the liver injury was progressive in 57% patients, with 43% mortality. Rising bilirubin and AST/ALT ratio predicted mortality among cirrhosis patients. CONCLUSIONS: SARS-Cov-2 infection causes significant liver injury in CLD patients, decompensating one fifth of cirrhosis, and worsening the clinical status of the already decompensated. The CLD patients with diabetes and obesity are more vulnerable and should be closely monitored.


Assuntos
Insuficiência Hepática Crônica Agudizada , Infecções por Coronavirus , Cirrose Hepática , Pandemias , Pneumonia Viral , Insuficiência Hepática Crônica Agudizada/diagnóstico , Insuficiência Hepática Crônica Agudizada/virologia , Ásia/epidemiologia , Betacoronavirus/isolamento & purificação , COVID-19 , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/fisiopatologia , Infecções por Coronavirus/terapia , Progressão da Doença , Feminino , Humanos , Cirrose Hepática/diagnóstico , Cirrose Hepática/epidemiologia , Cirrose Hepática/etiologia , Testes de Função Hepática/métodos , Testes de Função Hepática/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Gravidade do Paciente , Pneumonia Viral/epidemiologia , Pneumonia Viral/fisiopatologia , Pneumonia Viral/terapia , Prognóstico , Medição de Risco , Fatores de Risco , SARS-CoV-2
6.
J Hepatol ; 70(4): 684-691, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30529387

RESUMO

BACKGROUND & AIMS: Sorafenib is first-line standard of care for patients with advanced hepatocellular carcinoma (HCC), yet it confers limited survival benefit. Therefore, we aimed to compare clinical outcomes of sorafenib combined with concurrent conventional transarterial chemoembolization (cTACE) vs. sorafenib alone in patients with advanced HCC. METHODS: In this investigator-initiated, multicenter, phase III trial, patients were randomized to receive sorafenib alone (Arm S, n = 169) or in combination with cTACE on demand (Arm C, n = 170). Sorafenib was started within 3 days and cTACE within 7-21 days of randomization. The primary endpoint was overall survival (OS). RESULTS: For Arms C and S, the median OS was 12.8 vs. 10.8 months (hazard ratio [HR] 0.91; 90% CI 0.69-1.21; p = 0.290); median time to progression, 5.3 vs. 3.5 months (HR 0.67; 90% CI 0.53-0.85; p = 0.003); median progression-free survival, 5.2 vs. 3.6 months (HR 0.73; 90% CI 0.59-0.91; p = 0.01); and tumor response rate, 60.6% vs. 47.3% (p = 0.005). For Arms C and S, serious (grade ≥3) adverse events occurred in 33.3% vs. 19.8% (p = 0.006) of patients and included increased alanine aminotransferase levels (20.3% vs. 3.6%), hyperbilirubinemia (11.8% vs. 3.0%), ascites (11.8% vs. 4.2%), thrombocytopenia (7.2% vs. 1.2%), anorexia (7.2% vs. 1.2%), and hand-foot skin reaction (10.5% vs. 11.4%). A post hoc subgroup analysis compared OS in Arm C patients (46.4%) receiving ≥2 cTACE sessions to Arm S patients (18.6 vs. 10.8 months; HR 0.58; 95% CI 0.40-0.82; p = 0.006). CONCLUSION: Compared with sorafenib alone, sorafenib combined with cTACE did not improve OS in patients with advanced HCC. However, sorafenib combined with cTACE significantly improved time to progression, progression-free survival, and tumor response rate. Sorafenib alone remains the first-line standard of care for patients with advanced HCC. LAY SUMMARY: For patients with advanced hepatocellular carcinoma requiring sorafenib therapy, co-administration with conventional transarterial chemoembolization did not improve overall survival compared to sorafenib alone. Therefore, sorafenib alone remains the first-line standard of care for patients with advanced hepatocellular carcinoma. Clinical Trial Number: NCT01829035.


Assuntos
Antineoplásicos/uso terapêutico , Carcinoma Hepatocelular/tratamento farmacológico , Quimioembolização Terapêutica/métodos , Neoplasias Hepáticas/tratamento farmacológico , Sorafenibe/uso terapêutico , Idoso , Alanina Transaminase/sangue , Antineoplásicos/administração & dosagem , Antineoplásicos/efeitos adversos , Ascite/etiologia , Quimioembolização Terapêutica/efeitos adversos , Terapia Combinada , Feminino , Seguimentos , Humanos , Hiperbilirrubinemia/etiologia , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Sorafenibe/administração & dosagem , Sorafenibe/efeitos adversos , Trombocitopenia/etiologia
7.
Nanoscale ; 9(33): 11881-11887, 2017 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-28638901

RESUMO

The fabrication of large-area and well-ordered nanostructures using lithographic techniques is challenging. We have developed novel approaches for sub-50 nm nanopatterning using an electrohydrodynamic lithography (EHL) technique by tailoring experimental parameters such as applied voltage, stamp features, filling ratio, and choice of resist film. We obtain a sub-50 nm pattern replica from a master stamp that contains an array of line patterns having 50 nm widths. Moreover, we show that a far-smaller pattern replication than the original pattern size can be readily obtained by carefully adjusting the experimental conditions. Perfect- and much smaller-pattern replicas have been realized from the master stamp with an array of hole patterns having a 400 nm hole size by tuning the filling ratio. We also demonstrate that an array of 30 nm graphene nanoribbons can be easily fabricated by exploring a hierarchical core-shell template structure employing a bilayer resist film via an EHL technique. The proposed minimal-contact patterning method is simple, versatile, and inexpensive and has potential to become a powerful technique for realizing feasible ultrafine nanostructures on a wafer scale.

8.
ACS Appl Mater Interfaces ; 9(15): 13571-13576, 2017 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-28351132

RESUMO

We investigate the effect of electric field on VO2 back-gated field effect transistor (FET) devices. Using hybrid dielectric layers, we demonstrate the highest resistance modulation on the order of 102 in VO2 at a positive gate bias of 80 V (1.6 MV/cm). VO2 FET devices are prepared on SiO2 substrates of different thicknesses (100-300 nm) and hybrid dielectric layers of Al2O3/SiO2 (500 nm). For thicknesses less than 300 nm, no electric-field effects are observed, whereas for a 300 nm thickness, a small decrease in resistance is observed under a 0.2 MV/cm electric field. Under the electrostatic effect, the carrier concentration increases in VO2 devices, decreasing the resistance and the transition temperature from 66.75 to 64 °C. The leakage analysis shows that the interface quality of VO2 films on hybrid dielectric layers can be further improved. These studies suggest a multilevel fast resistance switching with the electric field and give an insight into the gate-source leakage current, which limits the phase transition in VO2 in an electric field.

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