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1.
ACS Sens ; 9(5): 2529-2539, 2024 05 24.
Artigo em Inglês | MEDLINE | ID: mdl-38723609

RESUMO

Hydrogen (H2) is crucial in the future global energy landscape due to its eco-friendly properties, but its flammability requires precise monitoring. This study introduces an innovative thermocatalytic H2 sensor utilizing ultrathin mica sheets as substrates, coated on both sides with Pd nanocluster (NC) films. The ultrathin mica substrate ensures robustness and flexibility, enabling the sensor to withstand high temperatures and mechanical deformation. Additionally, it simplifies the fabrication process by eliminating the need for complex microelectro-mechanical systems (MEMS) technology. Constructed through cluster beam deposition, the sensor exhibits exceptional characteristics, including a wide concentration range (from 500 ppm to 4%), rapid response and recovery times (3.1 and 2.4 s for 1% H2), good selectivity, high stability, and repeatability. The operating temperature can be as low as 40 °C, achieving remarkably low power consumption. The study explores the impact of double-sided versus single-sided catalytic layers, revealing significantly higher sensitivity and response with the double-sided configuration due to the increased catalytic surface area. Additionally, the research investigates the relationship between the deposition amount of Pd NCs and the sensor's sensitivity, identifying an optimal value that maximizes performance without excessive use of Pd. The sensor's innovative design and excellent performance position it as a promising candidate for meeting the demands of a hydrogen-based energy economy.


Assuntos
Silicatos de Alumínio , Hidrogênio , Nanopartículas Metálicas , Paládio , Paládio/química , Hidrogênio/química , Catálise , Nanopartículas Metálicas/química , Silicatos de Alumínio/química , Temperatura , Propriedades de Superfície
2.
Phys Chem Chem Phys ; 26(17): 13364-13373, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38639921

RESUMO

In this study, we successfully synthesize palladium-decorated indium trioxide (Pd/In2O3) hybrid nanoclusters (NCs) using an advanced dual-target cluster beam deposition (CBD) method, a significant stride in developing high-performance ethanol sensors. The prepared Pd/In2O3 hybrid NCs exhibit exceptional sensitivity, stability, and selectivity to low concentrations of ethanol vapor, with a maximum response value of 101.2 at an optimal operating temperature of 260 °C for 6 at% Pd loading. The dynamic response of the Pd/In2O3-based sensor shows an increase in response with increasing ethanol vapor concentrations within the range of 50 to 1000 ppm. The limit of detection is as low as 24 ppb. The sensor exhibits a high sensitivity of 28.24 ppm-1/2, with response and recovery times of 2.7 and 4.4 seconds, respectively, for 100 ppm ethanol vapor. Additionally, the sensor demonstrates excellent repeatability and stability, with only a minor decrease in response observed over 30 days and notable selectivity for ethanol compared to other common volatile organic compounds. The study highlights the potential of Pd/In2O3 NCs as promising materials for ethanol gas sensors, leveraging the unique capabilities of CBD for controlled synthesis and the catalytic properties of Pd for enhanced gas-sensing performance.

3.
Postgrad Med J ; 100(1181): 135-141, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38055911

RESUMO

At present, both the incidence and mortality rates of colorectal cancer are on the rise, making early screening a crucial tool in reducing the fatality rate. Although colonoscopy is the recommended method according to the guidelines, compliance tends to be poor. The fecal immunochemical test (FIT), a new technology that uses latex immunoturbidimetry to detect fecal blood, offers high specificity and sensitivity. Additionally, it is low-cost, easy to operate, and less likely to be affected by food and drugs, thus improving the compliance rate for population screening. Compared to other screening techniques, FIT represents a safer and more accurate option. This article reviews the application of FIT in early colorectal cancer screening.


Assuntos
Neoplasias Colorretais , Programas de Rastreamento , Humanos , Programas de Rastreamento/métodos , Neoplasias Colorretais/diagnóstico , Colonoscopia , Detecção Precoce de Câncer/métodos , Sangue Oculto , Fezes
4.
Anticancer Agents Med Chem ; 24(3): 169-176, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37990428

RESUMO

The National Cancer Center published a comparative report on cancer data between China and the United States in the Chinese Medical Journal, which shows that colorectal cancer (CRC) ranks second in China and fourth in the United States. It is worth noting that since 2000, the case fatality rate of CRC in China has skyrocketed, while the United States has gradually declined. Finding tumor markers with high sensitivity and specificity is our primary goal to reduce the case fatality rate of CRC. Studies have shown that CRD-BP (Insulin-like growth factor 2 mRNA-binding protein 1) can affect a variety of signaling pathways, such as Wnt.nuclear factor KB (NF-κB), and Hedgehog, and has good biological effects as a therapeutic target for CRC. CRD-BP is expected to become a tumor marker with high sensitivity and specificity of CRC. This paper reviews the research on CRD-BP as a tumor marker of CRC.


Assuntos
Biomarcadores Tumorais , Neoplasias Colorretais , Humanos , Biomarcadores Tumorais/genética , Transdução de Sinais , NF-kappa B/metabolismo , Neoplasias Colorretais/metabolismo , Linhagem Celular Tumoral , Proliferação de Células , Regulação Neoplásica da Expressão Gênica
5.
ACS Appl Mater Interfaces ; 15(50): 58723-58733, 2023 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-38055918

RESUMO

The integration of an electrochromic (EC), energy storage, and adaptive camouflage system into a multifunctional electronic device is highly desirable and yet challenging. In this work, two carbazole-based conjugated polymers were prepared to achieve a reversible color change from transparent to yellow, green, and blue-green by easy electrochemical polymerization. Due to its dendritic geometry, the conjugated polymer p3CBCB exhibits a loosely packed structure with a relatively higher specific surface area than pCBCB, as well as a relatively better ionic conductivity. The kinetic and galvanostatic charge-discharge (GCD) study reveals that p3CBCB has superior properties with larger optical contrast and volumetric capacitance. Moreover, EC supercapacitors (ECSCs) are constructed with p3CBCB as the EC layer and ZnO@PEDOT:PSS as the ion storage layer. The dual function of a ZnO interface layer on improvement in reflectivity contrast (ΔR% > 35.1%) and cycling stability (over 40,000 cycles) using ZnO as a reflective and protective layer is demonstrated in an ion storage layer. Additionally, patterned prototype devices based on the design of double-sided ITO glass were successfully assembled, which can simulate conditions of various natural environments including forests, wilderness, and deserts. This study provides new ideas not only for the preparation of conjugated polymers that can simultaneously realize reversible transparent-yellow-green conversion but also for the achievement of high coloration efficiency, high reflectivity contrast, and good stability of ECSCs for adaptive camouflage.

6.
Adv Mater ; 35(28): e2300510, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37029773

RESUMO

Fabricating solution-processible host material for thermally activated delayed fluorescence (TADF) emitter remains a formidable challenge for organic light-emitting diodes (OLEDs). In this work, two new host materials, namely 3CzAcPy and 9CzAcPy, are found to exhibit high triplet energy levels, high thermal stability, and excellent film morphology from a solution process. An in-depth analysis on the photophysical data and device performance reveals the isomeric effect of the host materials has a significant impact not only on the host properties, but also on the host-dopant interactions and thus the performance of the resulting solution-processed TADF OLEDs. Impressively, the new hosts are proven to be suitable for both donor-acceptor type and multi-resonance TADF emitters, achieving state-of-the-art device performance. By using the new host 9CzAcPy, solution-processed OLED based on a donor-acceptor TADF emitter of DPAC-PCN, a maximum external quantum efficiency (EQE) of 29.5% is achieved, and solution-processed narrowband OLED based on a multiple-resonance TADF emitter of BN-CP1 acquires a maximum EQE of 26.6%. These efficiencies represent the highest values among the solution-processed TADF OLEDs. This study highlights the significance of host-dopant interactions in modulating the electroluminescence performance of TADF emitters, and provides an effective design principle for solution-processible host materials.


Assuntos
Vibração , Fluorescência , Isomerismo
7.
Sensors (Basel) ; 23(4)2023 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-36850671

RESUMO

Binocular endoscopy is gradually becoming the future of minimally invasive surgery (MIS) thanks to the development of stereo vision. However, some problems still exist, such as the low reconstruction accuracy, small surgical field, and low computational efficiency. To solve these problems, we designed a framework for real-time dense reconstruction in binocular endoscopy scenes. First, we obtained the initial disparity map using an SGBM algorithm and proposed the disparity confidence map as a dataset to provide StereoNet training. Then, based on the depth map predicted by StereoNet, the corresponding left image of each depth map was input into the Oriented Fast and Brief-Simultaneous Localization and Mapping (ORB-SLAM) framework using an RGB-D camera to realize the real-time dense reconstruction of the binocular endoscopy scene. The proposed algorithm was verified in the stomach phantom and a real pig stomach. Compared with the ground truth, the proposed algorithm's RMSE is 1.620 mm, and the number of effective points in the point cloud is 834,650, which is a significant improvement in the mapping ability compared with binocular SLAM and ensures the real-time performance of the algorithm while performing dense reconstruction. The effectiveness of the proposed algorithm is verified.

8.
Angew Chem Int Ed Engl ; 62(13): e202217080, 2023 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-36722386

RESUMO

Achieving high efficiency and low efficiency roll-off simultaneously is of great significance for further application of thermally activated delayed fluorescent (TADF) emitters. A balance between radiative decay and reversed intersystem crossing must be carefully established. Herein, we propose a qunolino-acridine (QAc) donor composing two acridine with both planar (pAc) and bended (bAc) geometries. Combining with triazine, a TADF emitter QAc-TRZ is assembled. The pAc provides a well interaction with triazine which ensures a decent TADF behavior, while the bAc offers a delocalization of highest occupied molecular orbital (HOMO) which guarantees an enhancement of radiative decay. Remarkably, QAc-TRZ enables a highly efficient organic light emitting diode (OLED) with maximum external quantum efficiency (EQE) of 37.3 %. More importantly, the efficiencies under 100/1000 cd m-2 stay 36.3 % and 31.7 %, respectively, and remain 21.5 % even under 10 000 cd m-2 .

9.
Food Funct ; 13(18): 9470-9480, 2022 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-35983876

RESUMO

Inhibition of ferroptosis in intestinal epithelial cells ameliorates clinical symptoms and improves endoscopic presentations in inflammatory bowel disease (IBD). Licorice is used worldwide in food and medicine fields. Liquiritin, a flavonoid component in licorice, is an effective substance used as an anti-inflammatory, antioxidant food that has been shown to improve chemically induced colitis. Herein we evaluated the therapeutic effects of liquiritin on colitis and determined whether liquiritin could affect colitis by modulating ferroptosis in epithelial cells. A colitis model was induced in mice by oral administration with 2.5% DSS dissolved in drinking water. The results showed that liquiritin significantly alleviated symptoms, suppressed intestinal inflammation and restored the epithelial barrier function in the colitis mouse model. Liquiritin supplementation upregulated colonic ferritin expression, increased the storage of cellular iron, reduced the cellular iron level and further inhibited ferroptosis in epithelial cells from the colitis model. Pharmacological stimulation of ferroptosis largely blocked liquiritin-induced alleviation of colitis. Peroxiredoxin-6 (Prdx6) expression was significantly decreased in the DSS group, which was reversed by liquiritin treatment. Genetic or pharmacological silencing of Prdx6 largely reversed liquiritin-induced modulation of the ferritin/iron level and ferroptosis in epithelial cells. Molecular docking results showed that liquiritin could bind to Prdx6 through the hydrogen bond interaction with amino acid residues Thr208, Val206 and Pro203. In conclusion, liquiritin treatment largely alleviated DSS induced colitis by inhibiting ferroptosis in epithelial cells. Liquiritin negatively regulated ferroptosis in epithelial cells in colitis by activating Prdx6, increasing the expression of ferritin and subsequently reducing the cellular iron level.


Assuntos
Colite , Ferroptose , Flavanonas , Peroxirredoxina VI , Aminoácidos/metabolismo , Animais , Anti-Inflamatórios/metabolismo , Antioxidantes/metabolismo , Colite/induzido quimicamente , Colite/tratamento farmacológico , Colite/genética , Sulfato de Dextrana/efeitos adversos , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Ferritinas/metabolismo , Flavanonas/farmacologia , Glucosídeos/farmacologia , Ferro/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Simulação de Acoplamento Molecular , Peroxirredoxina VI/metabolismo
10.
Biomed Res Int ; 2022: 9599571, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35845931

RESUMO

Objective: To investigate the value of transabdominal combined transvaginal color Doppler ultrasonography in the diagnosis of uterine adenomyoma. Methods: A total of 80 patients with suspected uterine adenomyoma in our hospital from January 2019 to December 2021 were selected as the study subjects. All of them were examined by transabdominal color Doppler ultrasound (TA-CDUS) and transvaginal color Doppler ultrasound (TV-CDUS), and the postoperative pathological examination results were taken as the gold standard to analyze the diagnostic efficacy of different examination methods for uterine adenomyoma. Results: By postoperative pathological biopsy, 46 cases (57.50%) were diagnosed as positive and 34 cases (42.50%) were diagnosed as negative, including 29 cases of uterine adenomyoma and 5 other cases. The sensitivity, accuracy, and negative predictive value of TA-CDUS combined with TV-CDUS in the diagnosis of adenomyoma were higher than those of TA-CDUS (P < 0.05), and the Kappa value between TA-CDUS and pathological diagnosis was 0.923, which was higher than the 0.615 between TV-CDUS and pathological diagnosis. TA-CDUS combined with TV-CDUS showed that there were significant differences in the distribution of Adier blood flow grades between patients with uterine adenomyoma and uterine fibroids (P < 0.05), and the Adier blood flow grades of patients with uterine adenomyoma were mainly grade 0 and grade I; and the resistance index (RI), peak systolic velocity (Vs), and pulsatile index (PI) in patients with uterine adenomyoma were higher than those in patients with uterine fibroids (P < 0.05). Conclusion: Compared with TA-CDUS, TA-CDUS combined with TV-CDUS is more sensitive and accurate in the diagnosis of uterine adenomyoma and has a good consistency with pathological diagnosis results. Attention should be paid to the blood flow parameter values in the differential diagnosis of uterine fibroids.


Assuntos
Adenomioma , Leiomioma , Adenomioma/diagnóstico por imagem , Adenomioma/cirurgia , Feminino , Humanos , Leiomioma/diagnóstico por imagem , Valor Preditivo dos Testes , Sensibilidade e Especificidade , Ultrassonografia Doppler em Cores , Útero/diagnóstico por imagem
11.
Angew Chem Int Ed Engl ; 61(29): e202201588, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-35536106

RESUMO

Multi-resonance TADF (MR-TADF) emitters are promising for high-resolution OLEDs, but the concurrent optimization of excited-state dynamics and color purity remains a tough challenge. Herein, three deep-blue MR-TADF compounds (BN1-BN3) featuring gradually enlarged ring-fused structures and increased rigidity are accessed by lithium-free borylation in high yields from the same precursor, with all the emitters possessing CIEy coordinates below 0.08. Structure-property investigations demonstrate a strategic improvement of the oscillator strength (fosc ) and acceleration of the reverse intersystem crossing (RISC) process by extending the π-skeleton, where BN3 realizes a maximum external quantum efficiency (EQE) of 37.6 % and reduced roll-off, thus showing the best efficiency reported for deep-blue TADF OLEDs. The internal regulation of the efficiency and color purity of these compounds validate the general effectiveness to achieve advanced deep-blue narrowband emitters with higher-order boron/nitrogen-based MR motifs.

12.
Small ; 18(23): e2200634, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35435324

RESUMO

The development of hydrogen sensors is of paramount importance for timely leak detection and remains a crucial unmet need. Palladium-based materials, well known as hydrogen sensors, still suffer from poisoning and deactivation. Here, a hybrid hydrogen sensor consisting of a Pd nanocluster (NC) film, a metal-organic framework (MOF), and a polymer, are proposed. The polymer coating, as a protection layer, endows the sensor with excellent H2 selectivity and CO-poisoning resistance. The MOF serves as an interface layer between the Pd NC film and the polymer layer, which alters the nature of the interaction with hydrogen and leads to significant sensing performance improvements, owing to the interfacial electronic coupling between Pd NCs and the MOF. The strategy overcomes the shortcomings of retarded response speed and degraded sensitivity induced by the polymer coating of a Pd NC film-polymer hybrid system. This is the first exhibition of a hydrogen-sensing enhancement mechanism achieved by engineering the electronic coupling between Pd and a MOF. The work establishes a deep understanding of the hydrogen-sensing enhancement mechanism at the nanoscale and provides a feasible strategy to engineer next-generation gas-sensing nanodevices with superior sensing figures of merit via hybrid material systems.


Assuntos
Estruturas Metalorgânicas , Nanoestruturas , Hidrogênio , Paládio , Polímeros
13.
Light Sci Appl ; 11(1): 56, 2022 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-35273150

RESUMO

Revealing the photoluminescence (PL) origin and mechanism is a most vital but challenging topic of carbon dots. Herein, confined-domain crosslink-enhanced emission (CEE) effect was first studied by a well-designed model system of carbonized polymer dots (CPDs), serving as an important supplement to CEE in the aspect of spatial interactions. The "addition-condensation polymerization" strategy was adopted to construct CPDs with substituents exerting different degrees of steric hindrance. The effect of confined-domain CEE on the structure and luminescence properties of CPDs have been systematically investigated by combining characterizations and theoretical calculations. Such tunable spatial interactions dominated the coupling strength of the luminophores in one particle, and eventually resulted in the modulated PL properties of CPDs. These findings provide insights into the structural advantages and the PL mechanism of CPDs, which are of general significance to the further development of CPDs with tailored properties.

14.
J Phys Chem Lett ; 13(6): 1563-1570, 2022 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-35138107

RESUMO

For the direct luminescence of triplet excitons, different mechanisms have been proposed for realizing pure organic room-temperature phosphorescence (RTP). To further verify the mechanism of folding-induced spin-orbit coupling (SOC) enhancement, two analogues of thianthrene (TA) were introduced by gradually replacing the sulfur atom with an oxygen atom for a systematical comparison, corresponding to phenoxathiine (PX) and dioxins (DX) molecules with increasing folding dihedral angles (or decreasing degrees of folding). Photophysical measurements show an obviously enhanced RTP efficiency from DX and PX to TA, which is consistent with their greatly enhanced SOC with a decrease in folding dihedral angle. The folding angle-dependent SOC calculations for each molecule reveal that this enhanced RTP is dominated by folding-induced SOC enhancement, in contrast with the negligible heavy-atom effect from oxygen to sulfur. This work further validates the rationality of the folding-induced SOC enhancement mechanism, which provides an innovative molecular design strategy for developing efficient pure organic RTP materials using folding structures.

15.
Gut ; 71(11): 2205-2217, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35173042

RESUMO

OBJECTIVE: Dysbiosis of the intestinal fungal community has been observed in inflammatory bowel disease (IBD); however, its potential role in IBD development and prevention remains unclear. Here, we explored the biological effects and molecular mechanisms of intestinal fungi isolated from human faeces on colitis in mice. DESIGN: Intestinal fungal strains with differential abundance in IBD were cultivated in human faeces and their effects on various mouse models of experimental colitis were evaluated. In addition, the bioactive metabolites secreted by the target fungus were accurately identified and their pharmacological effects and potential molecular targets were investigated in vitro and in vivo. RESULTS: The abundance of Candida spp was significantly higher in patients with IBD. After large-scale human intestinal fungal cultivation and functional analysis, Candida metapsilosis M2006B significantly attenuated various models of experimental colitis in wild-type, antibiotic-treated, germ-free, and IL10-/- mice by activating farnesoid X receptor (FXR). Among the seven acyclic sesquiterpenoids (F1-F7) identified as major secondary metabolites of M2006B, F4 and F5 attenuated colitis in mice by acting as novel FXR agonists. The therapeutic effects of M2006B and its metabolites on colitis via specific FXR activation were confirmed in Fxr -/- mice. CONCLUSION: This study revealed that C. metapsilosis M2006B significantly attenuated colitis in mice and identified two acyclic sesquiterpenoids (F4 and F5) as major active metabolites of M2006B. Notably, these metabolites were able to effectively treat experimental colitis by selectively activating FXR. Together, this study demonstrates that M2006B could be a beneficial intestinal fungus for treating and preventing IBD.


Assuntos
Colite , Doenças Inflamatórias Intestinais , Sesquiterpenos , Animais , Antibacterianos/uso terapêutico , Candida parapsilosis , Colite/tratamento farmacológico , Colite/metabolismo , Modelos Animais de Doenças , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Interleucina-10 , Camundongos , Camundongos Endogâmicos C57BL , Receptores Citoplasmáticos e Nucleares , Sesquiterpenos/farmacologia , Sesquiterpenos/uso terapêutico
16.
ACS Appl Mater Interfaces ; 13(49): 59035-59042, 2021 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-34852195

RESUMO

Developing organic thermally activated delayed fluorescence (TADF) emitters with high efficiency and narrowband emissions is crucial and challenging for high-quality organic light-emitting diodes (OLEDs). Here, three multiresonance TADF emitters DPACzBN1, DPACzBN2, and DPACzBN3 are designed via a peripheral decoration strategy and synthesized through a lithium intermediate cascade borylation reaction (15% yield for DPACzBN1) or a more efficient lithium-free direct borylation reaction (45% yield for DPACzBN2 and 75% yield for DPACzBN3). All the emitters exhibit a similar blue emission with small full-width at half maximum (fwhm) values as low as 20 nm in toluene solutions. The introduction of the diphenylamino moiety into the parent molecule DPACzBN1 can not only maintain the high photoluminescence quantum yields over 90% but also narrow the bandwidth and enhance the rate constant of the reverse intersystem crossing process, as well as suppress the spectral broadening in devices. Benefiting from the excellent TADF properties and good inhibition of spectral broadening, TADF OLEDs based on DPACzBN3 achieve the highest maximum external quantum efficiency of 27.7% and the smallest fwhm of 24 nm among the three emitters.

18.
Angew Chem Int Ed Engl ; 60(22): 12376-12380, 2021 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-33768658

RESUMO

Spiro-acridan (SpA) derivatives possess a great potential in preparing efficient thermally activated delayed fluorescent (TADF) emitters. However, the conventional synthetic routes are cost-expensive and time-consuming. The development of a simple procedure to synthesize SpAs is still in urgent pursuing appreciated by academic and industrial communities. In this contribution, we present a feasible acid-catalyzed solvent-free metal-free cyclization between diarylamines and ketones to construct SpAs. The as-constructed moieties provide a wide possibility to assemble efficient TADF emitters. As an example, D2T-TR with high photoluminescent quantum yield and proper TADF character is applied in organic light emitting diodes (OLEDs) which achieves a maximum external quantum efficiency (EQE) of 27.1 %. This work shows us a bright inspiration on developing excellent organic optoelectronic materials and an effective tool to realize it.

19.
Molecules ; 26(4)2021 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-33672662

RESUMO

A new series of tetrahedral heteroleptic copper(I) complexes exhibiting efficient thermally-activated delayed fluorescence (TADF) in green to orange electromagnetic spectral regions has been developed by using D-A type N^N ligand and P^P ligands. Their structures, electrochemical, photophysical, and electroluminescence properties have been characterized. The complexes exhibit high photoluminescence quantum yields (PLQYs) of up to 0.71 at room temperature in doped film and the lifetimes are in a wide range of 4.3-24.1 µs. Density functional theory (DFT) calculations on the complexes reveal the lowest-lying intraligand charge-transfer excited states that are localized on the N^N ligands. Solution-processed organic light emitting diodes (OLEDs) based on one of the new emitters show a maximum external quantum efficiency (EQE) of 7.96%.


Assuntos
Complexos de Coordenação/química , Cobre/química , Corantes Fluorescentes/química , Teoria Quântica , Temperatura , Ligantes , Estrutura Molecular , Soluções
20.
Comput Med Imaging Graph ; 88: 101861, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33497891

RESUMO

Colorectal cancer (CRC) is the second leading cause of cancer-related mortality worldwide. In coping with it, histopathology image analysis (HIA) provides key information for clinical diagnosis of CRC. Nowadays, the deep learning methods are widely used in improving cancer classification and localization of tumor-regions in HIA. However, these efforts are both time-consuming and labor-intensive due to the manual annotation of tumor-regions in the whole slide images (WSIs). Furthermore, classical deep learning methods to analyze thousands of patches extracted from WSIs may cause loss of integrated information of image. Herein, a novel method was developed, which used only global labels to achieve WSI classification and localization of carcinoma by combining features from different magnifications of WSIs. The model was trained and tested using 1346 colorectal cancer WSIs from the Cancer Genome Atlas (TCGA). Our method classified colorectal cancer with an accuracy of 94.6 %, which slightly outperforms most of the existing methods. Its cancerous-location probability maps were in good agreement with annotations from three individual expert pathologists. Independent tests on 50 newly-collected colorectal cancer WSIs from hospitals produced 92.0 % accuracy and cancerous-location probability maps were in good agreement with the three pathologists. The results thereby demonstrated that the method sufficiently achieved WSI classification and localization utilizing only global labels. This weakly supervised deep learning method is effective in time and cost, as it delivered a better performance in comparison with the state-of-the-art methods.


Assuntos
Neoplasias Colorretais , Aprendizado Profundo , Humanos , Processamento de Imagem Assistida por Computador
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