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1.
Small ; 20(4): e2306516, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37715101

RESUMO

Antimony selenide (Sb2 Se3 ) is a highly promising photovoltaic material thanks to its outstanding optoelectronic properties, as well as its cost-effective and eco-friendly merits. However, toxic CdS is widely used as an electron transport layer (ETL) in efficient Sb2 Se3 solar cells, which largely limit their development toward market commercialization. Herein, an effective green Cd-free ETL of SnOx is introduced and deposited by atomic layer deposition method. Additionally, an important post-annealing treatment is designed to further optimize the functional layers and the heterojunction interface properties. Such engineering strategy can optimize SnOx ETL with higher nano-crystallinity, higher carrier density, and less defect groups, modify Sb2 Se3 /SnOx heterojunction with better interface performance and much desirable "spike-like" band alignment, and also improve the Sb2 Se3 light absorber layer quality with passivated bulk defects and prolonged carrier lifetime, and therefore to enhance carrier separation and transport while suppressing non-radiative recombination. Finally, the as-fabricated Cd-free Mo/Sb2 Se3 /SnOx /ITO/Ag thin-film solar cell exhibits a stimulating efficiency of 7.39%, contributing a record value for Cd-free substrate structured Sb2 Se3 solar cells reported to date. This work provides a viable strategy for developing and broadening practical applications of environmental-friendly Sb2 Se3 photovoltaic devices.

2.
Inorg Chem ; 62(46): 19033-19042, 2023 Nov 20.
Artigo em Inglês | MEDLINE | ID: mdl-37931319

RESUMO

Chalcogenide glasses in the Na2S-GeS2-Ga2S3 pseudoternary system were synthesized using a combination route of melt-quenching and mechanical-milling methods. First, a glass rich in germanium (90GeS2-10Ga2S3) is synthesized by melt-quenching synthesis in a silica tube sealed under vacuum. This glass is used as a precursor for the second step of mechanochemistry to explore the Na2S-GeS2-Ga2S3 pseudoternary system. By using this synthesis route, the glass-forming ability is improved as the vitreous domain is enlarged, especially for Na- and Ga-rich compositions. The as-obtained amorphous powders are characterized by Raman spectroscopy, differential scanning calorimetry, X-ray total scattering, and pair distribution function (PDF) analysis. The evolution of the Raman features observed is reproduced using density functional theory calculations. Impedance spectroscopy was performed to determine the conductivity of the new glasses. The addition of germanium sulfide to the Na2S-Ga2S3 pseudobinary system enables one to increase the conductivity by 1 order of magnitude. The highest room-temperature ionic conductivity, as measured by impedance spectroscopy, is 1.8 × 10-5 S·cm-1.

3.
Cancer ; 129(19): 2999-3009, 2023 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-37449788

RESUMO

BACKGROUND: The role of carbohydrate antigen 19-9 (CA 19-9) in response assessment among patients with intrahepatic cholangiocarcinoma (iCCA) remains unknown. The authors studied the association of the CA 19-9 response (defined as a reduction >50% from baseline) with the radiologic response and the outcome in patients with unresectable iCCA. METHODS: A prospective cohort of 422 patients who were initially diagnosed with unresectable iCCA, had baseline CA 19-9 levels ≥100 U/mL, and received treatment with systemic therapies at the authors' institution between January 2017 and December 2021 were enrolled in this study. The radiologic response was assessed using the Response Evaluation Criteria in Solid Tumors version 1.1. A landmark assessment of the CA 19-9 response and the radiologic response was performed. The associations between CA 19-9 response and imaging response, progression-free survival (PFS), and overall survival (OS) were analyzed. RESULTS: Two hundred sixty-seven patients (63.3%) had a CA 19-9 response. A CA 19-9 response was observed in 123 of 132 (93.2%) radiologic responders and in 144 of 290 (49.7%) radiologic nonresponders (p < .001). CA 19-9 responders outperformed nonresponders in median PFS (10.6 vs. 3.6 months; hazard ratio [HR], 4.8 months; 95% confidence interval [CI], 3.8-6.0 months; p < .001) and OS (21.4 vs. 6.3 months; HR, 5.3 months; 95% CI, 4.2-6.7 months; p < .001). The common independent predictors of both OS and PFS included metastasis, CA 19-9 nonresponder status, and radiologic nonresponder status in multivariable analysis. CONCLUSIONS: CA 19-9 response is a valuable addition to assess tumor response and is associated with improved outcomes in patients with iCCA. Achieving a CA 19-9 response should be one of the therapeutic objectives of patients with iCCA after systemic therapies. PLAIN LANGUAGE SUMMARY: A decline in carbohydrate antigen 19-9 levels from elevated baseline levels should be one of the therapeutic aims of patients with intrahepatic cholangiocarcinoma who are managed with systemic therapies.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Humanos , Estudos Prospectivos , Colangiocarcinoma/tratamento farmacológico , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/patologia , Carboidratos/uso terapêutico , Estudos Retrospectivos
4.
Front Neurol ; 14: 1169440, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37332987

RESUMO

Objective: The optimal treatment approach for hemorrhagic moyamoya disease (HMMD) remains a topic of debate, particularly regarding the comparative efficacy of revascularization versus conservative treatment. Our study, which included a single-center case series and a systematic review with meta-analysis, aimed to determine whether surgical revascularization is associated with a significant reduction in postoperative rebleeding, ischemic events, and mortality compared to conservative treatment among East Asian HMMD patients. Methods: We conducted a systematic literature review by searching PubMed, Google Scholar, Wanfang Med Online (WMO), and the China National Knowledge Infrastructure (CNKI). The outcomes of surgical revascularization and conservative treatment, including rebleeding, ischemic events and mortality, were compared. The authors' institutional series of 24 patients were also included and reviewed in the analysis. Results: A total of 19 East Asian studies involving 1,571 patients as well as our institution's retrospective study of 24 patients were included in the study. In the adult patients-only studies, those who underwent revascularization had significantly lower rates of rebleeding, ischemic events, and mortality compared to those who received conservative treatment (13.1% (46/352) vs. 32.4% (82/253), P < 0.00001; 4.0% (5/124) vs. 14.9% (18/121), P = 0.007; and 3.3% (5/153) vs. 12.6% (12/95), P = 0.01, respectively). In the adult/pediatric patients' studies, similar statistical results of rebleeding, ischemic events, and mortality have been obtained (70/588 (11.9%) vs. 103/402 (25.6%), P = 0.003 or <0.0001 in a random or fixed-effects model, respectively; 14/296 (4.7%) vs. 26/183 (14.2%), P = 0.001; and 4.6% (15/328) vs. 18.7% (23/123), P = 0.0001, respectively). Conclusion: The current single-center case series and systematic review with meta-analysis of studies demonstrated that surgical revascularization, including direct, indirect, and a combination of both, significantly reduces rebleeding, ischemic events, and mortality in HMMD patients in the East Asia region. More well-designed studies are warranted to further confirm these findings.

5.
Materials (Basel) ; 16(3)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36770277

RESUMO

The Skutterudites CoSb3 material has been the focus of research for the conversion applications of waste heat to electricity due to its ability to accommodate a large variety of ions in the cages that have been proven effective in improving the thermoelectric performance. Although the co-doped CoSb3 bulk materials have attracted increasing attention and have been widely studied, co-doped CoSb3 thin films have been rarely reported. In this work, Ag and Ti were co-doped into CoSb3 thin films via a facile in situ growth method, and the influence of doping content in the thermoelectric properties was investigated. The results show that all the Ag and Ti co-doped CoSb3 thin films contain a pure well-crystallized CoSb3 phase. Compared to the un-doped thin film, the co-doped samples show simultaneous increase in the Seebeck coefficient and the electrical conductivity, leading to a distinctly enhanced power factor. The high power factor value can reach ~0.31 mWm-1K-2 at 623 K after appropriate co-doping, which is two times the value of the un-doped thin film we have been obtained. All the results show that the co-doping is efficient in optimizing the performance of the CoSb3 thin films; the key point is to control the doping element content so as to obtain high thermoelectric properties.

6.
Ying Yong Sheng Tai Xue Bao ; 33(9): 2413-2421, 2022 Sep.
Artigo em Chinês | MEDLINE | ID: mdl-36131657

RESUMO

The situations are complex and variant in the three stages of "carbon emission peak", "rapid reduction of carbon emission" and "deep decarbonization for carbon neutrality" in China's carbon neutralization roadmap. Forest carbon sequestration is an important means to achieve the goal of carbon neutralization in China. Its intertemporal allocation is a vital way to balance industrial emission reduction and forest carbon sequestration, reduce the cost of carbon neutrality, and gradually achieve the goal of carbon neutrality based on optimal cost. Based on the cost optimization allocation theory, we simulated the cost change process of three stages of carbon neutralization in China by quoting the theory of marginal carbon sequestration cost and combining with the existing domestic marginal abatement cost theory. The results showed that annual forest carbon sequestrations with the optimal cost in China was 20 million t, 775 million t and 1.982 billion t respectively in the three stages of "carbon emission peak", "rapid reduction of carbon emission" and "deep decarbonization for carbon neutrality", accounting for 1.8%, 17.5%, and 37.6% of the total emission reduction in each period. Compared with the way relying only on industrial emission reduction, forest carbon sequestration under the optimal cost design reduced the total cost by 48, 79136, and 909253 million US$ in the three stages of carbon neutralization, respectively. Due to the limited cost advantage of forest carbon sequestration, industrial emission reduction should be emphasized in the "carbon emission peak" stage. In the "rapid reduction of carbon emissions" stage, the cost advantage of forest carbon sequestration will be increasingly prominent. In the stage of "deep decarbonization for carbon neutrality", it is necessary to fully exploit the cost advantage of forest carbon sequestration to achieve the goal of "zero carbon" to avoid the risk of high costs, especially for industries with high decarbonization cost or that will never be completely decarbonized. The optimal cost design for forest carbon sequestration can save 988.437 billion US $ in carbon-neutral costs.


Assuntos
Sequestro de Carbono , Gases de Efeito Estufa , Carbono/análise , Dióxido de Carbono/análise , China , Florestas
7.
ACS Appl Mater Interfaces ; 14(28): 31986-31997, 2022 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-35793154

RESUMO

Antimony sulfide-selenide (Sb2(S,Se)3) is a promising light-harvesting material for stable and high-efficiency thin-film photovoltaics (PV) because of its excellent light-harvesting capability, abundant elemental storage, and excellent stability. This study aimed to expand the application of Sb2(S,Se)3 solar cells with a substrate structure as a flexible or tandem device. The use of a hydrothermal method accompanied by a postselenization process for the deposition of Sb2(S,Se)3 film based on the solar cell substrate structure was first demonstrated. The mechanism of postselenization treatment on crystal growth promotion of the Sb2(S,Se)3 film and the defect passivation of the Sb2(S,Se)3 solar cell were revealed through different characterization methods. The crystallinity and the carrier transport property of the Sb2(S,Se)3 film improved, and both the interface defect density of the Sb2(S,Se)3/CdS interface and the bulk defect density of the Sb2(S,Se)3 absorber decreased. Through these above-mentioned processes, the transport and collection of electronics can be improved, and the defect recombination loss can be reduced. By using postselenization treatment to optimize the absorber layer, Sb2(S,Se)3 solar cells with the configuration SLG/Mo/Sb2(S,Se)3/CdS/ITO/Ag achieved an efficiency of 4.05%. This work can provide valuable information for the further development and improvement of Sb2(S,Se)3 solar cells.

8.
Adv Mater ; 34(14): e2109078, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35104384

RESUMO

Despite the fact that antimony triselenide (Sb2 Se3 ) thin-film solar cells have undergone rapid development in recent years, the large open-circuit voltage (VOC ) deficit still remains as the biggest bottleneck, as even the world-record device suffers from a large VOC deficit of 0.59 V. Here, an effective interface engineering approach is reported where the Sb2 Se3 /CdS heterojunction (HTJ) is subjected to a post-annealing treatment using a rapid thermal process. It is found that nonradiative recombination near the Sb2 Se3 /CdS HTJ, including interface recombination and space charge region recombination, is greatly suppressed after the HTJ annealing treatment. Ultimately, a substrate Sb2 Se3 /CdS thin-film solar cell with a competitive power conversion efficiency of 8.64% and a record VOC of 0.52 V is successfully fabricated. The device exhibits a much mitigated VOC deficit of 0.49 V, which is lower than that of any other reported efficient antimony chalcogenide solar cell.

9.
Pharm Biol ; 60(1): 163-174, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-35001799

RESUMO

CONTEXT: Yi Shen An (YSA) is an investigational composite of traditional Chinese medicine (Reference: 2010L000974) for the treatment of renal disease. OBJECTIVE: To investigate the protective effects of YSA against membranous glomerulonephritis (MGN). MATERIALS AND METHODS: Male Sprague-Dawley rats were injected with cationic bovine serum albumin (C-BSA) to create a model of MGN. Then, rats were orally treated with YSA at doses of 0.25, 0.5, 1 and 2 g/kg for 35 successive days; prednisone (5 mg/kg) was used as a positive control. At the end of the experimental period, we performed a series of tests, including 24 h urinary protein, and biochemical, immunological, antioxidative, coagulation indices, and histopathological examination. RESULTS: YSA-1 g/kg significantly lowered urinary protein from 68.37 to 30.74 mg (p < 0.01). Meantime, total protein (TP) and albumin (ALB) recovered from 66.26 and 20.51 g/L to 76.08 and 35.64 g/L (p < 0.01), respectively. YSA removed the deposition of immunoglobulin G (IgG) and complement 3c (C3c), prevented inter-capillary cell hyperplasia on the glomerular basement membrane (GBM), and reduced electron-dense deposits and fusion of podocytes. In addition, serum IgG and superoxide dismutase were significantly elevated. In contrast, malondialdehyde, total cholesterol, triglyceride, circulating immune complex (CIC), and immunoglobulin M decreased in the YSA-treated group. Moreover, the blood coagulation dysfunction was adjusted. DISCUSSION AND CONCLUSIONS: These findings indicate YSA may exert a therapeutic effect against MGN through the inhibition of CIC formation, and the removal of IgG and C3c deposition from the GBM, thus supporting the development of further clinical trials.


Assuntos
Complexo Antígeno-Anticorpo/metabolismo , Medicamentos de Ervas Chinesas/farmacologia , Glomerulonefrite Membranosa/tratamento farmacológico , Animais , Cátions , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Medicamentos de Ervas Chinesas/administração & dosagem , Imunoglobulina G/sangue , Masculino , Prednisona/farmacologia , Ratos , Ratos Sprague-Dawley , Soroalbumina Bovina , Superóxido Dismutase/metabolismo
10.
ACS Appl Mater Interfaces ; 14(3): 4276-4284, 2022 Jan 26.
Artigo em Inglês | MEDLINE | ID: mdl-35034451

RESUMO

Antimony selenosulfide, Sb2(SSe)3, is recognized as an excellent photoactive material owing to its light harvesting capability. There is still room for improvement of the film quality for device performance improvement. Herein, an organic chloride salt [diethylamine hydrochloride, DEA(Cl)] has been introduced for fabricating Sb2(SSe)3 solar cells for the first time. A champion device with a power conversion efficiency (PCE) of 9.17% has been achieved with a relatively improved fill factor and open-circuit voltage (VOC). It has been revealed that DEA(Cl) successfully interacts with Sb2(SSe)3, which can facilitate the crystallization process to give rise to the closely packed bigger grain sizes with reduced surface cracks; it successfully suppressed the oxidized Sb species (Sb2O3) in the Sb2(SSe)3 film to give rise to phase purity, thus leading to superior surface morphology and electrical characteristics of DEA(Cl)-modified Sb2(SSe)3 absorber films. Chloride modification is thus efficiently helpful in suppressing interfacial defects, improving junction quality, and optimizing energy-level alignment. This facile interfacial modification demonstrates the remarkable potential for efficient Sb2(SSe)3 solar cells.

11.
Adv Sci (Weinh) ; 9(5): e2103547, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34939357

RESUMO

Flexible Bi2 Te3 -based thermoelectric devices can function as power generators for powering wearable electronics or chip-sensors for internet-of-things. However, the unsatisfied performance of n-type Bi2 Te3 flexible thin films significantly limits their wide application. In this study, a novel thermal diffusion method is employed to fabricate n-type Te-embedded Bi2 Te3 flexible thin films on flexible polyimide substrates, where Te embeddings can be achieved by tuning the thermal diffusion temperature and correspondingly result in an energy filtering effect at the Bi2 Te3 /Te interfaces. The energy filtering effect can lead to a high Seebeck coefficient ≈160 µV K-1 as well as high carrier mobility of ≈200 cm2 V-1 s-1 at room-temperature. Consequently, an ultrahigh room-temperature power factor of 14.65 µW cm-1 K-2 can be observed in the Te-embedded Bi2 Te3 flexible thin films prepared at the diffusion temperature of 623 K. A thermoelectric sensor is also assembled through integrating the n-type Bi2 Te3 flexible thin films with p-type Sb2 Te3 counterparts, which can fast reflect finger-touch status and demonstrate the applicability of as-prepared Te-embedded Bi2 Te3 flexible thin films. This study indicates that the thermal diffusion method is an effective way to fabricate high-performance and applicable flexible Te-embedded Bi2 Te3 -based thin films.

12.
ACS Appl Mater Interfaces ; 13(39): 46671-46680, 2021 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-34569779

RESUMO

Sb2Se3, one of the most desirable absorption materials for next-generation thin-film solar cells, has an excellent photovoltaic characteristic. The [hk1]-oriented (quasi-vertically oriented) Sb2Se3 thin film is more beneficial for promoting efficient carrier transport than the [hk0]-oriented Sb2Se3 thin film. Controlling thin-film orientation remains the main obstacle to the further improvement in the efficiency of Sb2Se3-based solar cells. In this work, the controlled [hk0] or [hk1] orientation of the Sb2Se3 precursor is readily adjusted by tuning the substrate temperature and the distance between the source and the sample in close-space sublimation (CSS). Well-crystallized stoichiometric Sb2Se3 thin films with the desired orientation and large crystal grains are successfully prepared after selenization. Sb2Se3 thin-film solar cells in a substrate configuration of glass/Mo/Sb2Se3/CdS/ITO/Ag are fabricated with a power conversion efficiency of 4.86% with a record open-circuit voltage (VOC) of 509 mV. The significant improvement in VOC is closely related to the quasi-vertically oriented Sb2Se3 absorber layer with reduced deep-level defect density in the bulk and defect passivation at the Sb2Se3/CdS heterojunction. This work indicates that CSS and selenization show a remarkable potential for the fabrication of high-efficiency Sb2Se3 solar cells.

13.
Sci Rep ; 11(1): 11081, 2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34040127

RESUMO

In order to decrease the number of lenses and the weight of thermal imaging devices, specific optical design are required by using gradient refractive index (GRIN) elements transparent in the infrared waveband. While widely used for making visible GRIN lenses with silicate glasses, the ion exchange process is very limited when applied to chalcogenide glasses due to their low Tg and relatively weak mechanical properties. In this paper, we develop chalco-halide glasses based on alkali halide (NaI) addition in a highly covalent GeSe2-Ga2Se3 matrix, efficient for tailoring a significant and permanent change of refractive by ion exchange process between K+ and Na+. Optical and structural properties of the glass samples were measured showing a diffusion length reaching more than 2 mm and a Gaussian gradient of refractive index Δn of 4.5.10-2. The obtained GRIN lenses maintain an excellent transmission in the second (3-5 µm) and third (8-12 µm) atmospheric windows.

15.
Front Pharmacol ; 11: 1073, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32754040

RESUMO

Excessive cerebral inflammation plays a key role in early brain injury (EBI) after subarachnoid hemorrhage (SAH). Berberine, an isoquinoline alkaloid isolated from Chinese herb Coptis chinensis, possesses anti-inflammatory, and neuroprotective effects. Here we evaluated the beneficial effects of berberine against SAH-induced inflammatory response and the subsequent brain injury. Our data showed that berberine treatment significantly inhibited microglia activation and proinflammatory cytokines release. Concomitant with suppressed cerebral inflammation, berberine mitigated the subsequent brain injury as demonstrated by improved neurological behavior, reduced brain edema, and decreased neural apoptosis. Moreover, berberine significantly inhibited high mobile group box 1 (HMGB1)/nuclear factor-κB (Nf-κB)-dependent pathway and enhanced sirtuin 1 (SIRT1) expression after SAH. Treatment with ex527, a selective SIRT1 inhibitor, reversed berberine-induced SIRT1 activation and inhibitory effects on HMGB1/Nf-κB activation. In addition, ex527 pretreatment abated the anti-inflammatory and neuroprotective effects of berberine on SAH. Taken together, these findings suggest that berberine provides beneficial effects against SAH-triggered cerebral inflammation by inhibiting HMGB1/Nf-κB pathway, which may be modulated by SIRT1 activation.

16.
HPB (Oxford) ; 22(8): 1197-1205, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-31843444

RESUMO

BACKGROUND: To compare outcomes of patients with arterially hyperenhancing intrahepatic cholangiocarcinomas (ICC) and arterially hypoenhancing ICCs after partial hepatectomy in a cohort with an analysis of prognostic factors. METHODS: From June 2009 to October 2011, a prospective cohort of 68 patients with single resectable ICCs (≤5 cm in diameter) underwent gadolinium contrast-enhanced dynamic-phase magnetic resonance imaging and were treated with partial hepatectomy. Patients were divided into those with arterially hyperenhancing ICCs (n = 28) or arterially hypoenhancing ICCs (n = 40). Clinic-radiologic-pathologic results and survival of these patients were compared and statistically analyzed. RESULTS: The median overall survival (OS) time was significantly longer in the arterially hyperenhancing ICCs (56.8 vs. 37.0 months) (p = 0.044). At pathologic evaluation, arterially hyperenhancing ICCs showed significantly higher microvessel count (MVC) than arterially hypoenhancing ICCs (106.2 ± 47.5 vs. 46.9 ± 21.6/mm2, p = 0.001). Arterial enhancement of ICCs was found to be an independent prognostic factor for longer survival. CONCLUSION: The presence of arterially hyperenhancing ICCs is related to higher MVC and exhibit a better OS time than arterially hypoenhancing ICCs after partial hepatectomy.


Assuntos
Neoplasias dos Ductos Biliares , Colangiocarcinoma , Neoplasias dos Ductos Biliares/diagnóstico por imagem , Neoplasias dos Ductos Biliares/cirurgia , Ductos Biliares Intra-Hepáticos/diagnóstico por imagem , Ductos Biliares Intra-Hepáticos/cirurgia , Colangiocarcinoma/diagnóstico por imagem , Colangiocarcinoma/cirurgia , Meios de Contraste , Humanos , Microvasos/diagnóstico por imagem , Estudos Prospectivos
17.
Nanoscale Adv ; 1(11): 4359-4364, 2019 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36134412

RESUMO

Graphene is an attractive candidate for developing high conductivity materials (HCMs) owing to an extraordinary charge mobility. While graphene itself is a semi-metal with an inherently low carrier density, and methods used for increasing carrier density normally also cause a marked decrease in charge mobility. Here, we report that ordered nitrogen doping can induce a pronounced increase in carrier density but does not harm the high charge mobility of graphene nanoribbons (GNRs), giving rise to an unprecedented ultrahigh conductivity in the system. Our first-principles calculations for orderly N-doped GNRs (referred to as C5N-GNRs) show that N-doping causes a significant shift-up of the Fermi level (ΔE F), resulting in the presence of multiple partially-filled energy bands (PFEDs) that primarily increase the carrier density of system. Notably, the PFEDs are delocalized well with integral and quantized transmissions, suggesting a negligible effect from N-doping on the charge mobility. Moreover, the PFEDs can cross the E F multiple times as the ribbon widens, causing the conductivity to increase monotonically and reach ultrahigh values (>15G 0) in sub-5 nm wide ribbons with either armchair or zigzag edges. Furthermore, a simple linear relationship between the doing concentration and the ΔE F was obtained, which provides a robust means for controlling the conductivity of C5N-GNRs. Our findings should be useful for understanding the effect of ordered atomic doping on the conductivity of graphene and may open new avenues for realizing graphene-based HCMs.

18.
Cancers (Basel) ; 10(9)2018 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-30150518

RESUMO

A multicenter study was performed to determine an optimal workflow for liquid biopsy in a clinical setting. In total, 549 plasma samples from 234 non-small cell lung cancer (NSCLC) patients were collected. Epidermal Growth Factor Receptor (EGFR) circulating cell-free tumor DNA (ctDNA) mutational analysis was performed using digital droplet PCR (ddPCR). The influence of (pre-) analytical variables on ctDNA analysis was investigated. Sensitivity of ctDNA analysis was influenced by an interplay between increased plasma volume (p < 0.001) and short transit time (p = 0.018). Multistep, high-speed centrifugation both increased plasma generation (p < 0.001) and reduced genomic DNA (gDNA) contamination. Longer transit time increased the risk of hemolysis (p < 0.001) and low temperatures were shown to have a negative effect. Metastatic sites were found to be strongly associated with ctDNA detection (p < 0.001), as well as allele frequency (p = 0.034). Activating mutations were detected in a higher concentration and allele frequency compared to the T790M mutation (p = 0.003, and p = 0.002, respectively). Optimization of (pre-) analytical variables is key to successful ctDNA analysis. Sufficient plasma volumes without hemolysis or gDNA contamination can be achieved by using multistep, high-speed centrifugation, coupled with short transit time and temperature regulation. Metastatic site location influenced ctDNA detection. Finally, ctDNA levels might have further value in detecting resistance mechanisms.

19.
Nanoscale ; 10(28): 13511-13519, 2018 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-29972169

RESUMO

The performance of organic-inorganic hybrid thermoelectric thin films can be dramatically enhanced by optimizing energy filtering and carrier transport states at the organic-inorganic interfaces. In this work, p-type "Sb2Te3/CH3NH3I/Sb2Te3" multilayer thin films were firstly fabricated with varied contents of CH3NH3I, and then an annealing process was used in order to form homogeneous organic-inorganic hybrid thin films. The results revealed that the introduced organic component can promote thin film growth and develop a dense nanostructure with improved crystallinity, thus resulting in a significantly increased Seebeck coefficient and a reduced thermal conductivity as a result of the optimized electronic transport characteristics and enhanced effects of phonon scattering. As is expected, the thermoelectric performance of the hybrid-nanocomposite films is enhanced, achieving the maximum ZT value of 1.55 at a temperature of 413 K, which is several times higher than that of the as-fabricated film, thereby suggesting that the proposed strategy can be applied as an efficient method for the preparation of high-performance thermoelectric thin films.

20.
Oncol Lett ; 15(5): 7563-7570, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29725461

RESUMO

Malignant gliomas are treated with temozolomide (TMZ) at present, but often exhibit resistance to this agent. Cancer-initiating cells (CICs) have been suggested to lead to TMZ resistance. The mechanisms underlying CICs-based TMZ resistance are not fully understood. MicroRNAs (miRNAs) have been demonstrated to serve important roles in tumorigenesis and TMZ resistance. In the present study, a sphere forming assay and western blot analysis were performed to detect the formation of CICs and fibroblast activation protein α (FAP-α) protein expression. It was revealed that TMZ resistance promoted the formation of CICs and upregulated FAP-α expression in glioblastoma cells. Over-expressing FAP-α was also demonstrated to promote TMZ resistance and induce the formation of CICs in U251MG cells. In addition, using a reverse transcription-quantitative polymerase chain reaction, it was observed that miR-204 was downregulated in U251MG-resistant (-R) cells. miR-204 expression negatively correlated with the FAP-α levels in human glioblastoma tissues, and it may inhibit the formation of CICs and reverse TMZ resistance in U251MG-R cells. Therefore, it was concluded that miR-204 reversed temozolomide resistance and inhibited CICs phenotypes by degrading FAP-α in glioblastoma.

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