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2.
Chem Commun (Camb) ; 57(37): 4516-4519, 2021 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-33956025

RESUMO

Two-photon induced polymerization for three-dimensional (3D) printing has attracted increasing attention. Here, we report the two-photon induced polymerization of triethylene glycol divinyl ether (TEGDVE) in a porous polymer film using 4,4',4''-nitrilotribenzoic acid (NTB) as the photosensitizer and diphenyliodonium hexafluorophosphate (HIP) as the initiator, enabling the printing of multi-layer structures in the porous support.

4.
Spectrochim Acta A Mol Biomol Spectrosc ; 257: 119764, 2021 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-33848953

RESUMO

Hydrogen sulfide (H2S) played crucial roles in biological processes and daily life, and the abnormal level of H2S was associated with many physiological processes. In this paper, we designed and developed a dicyanomethylene-4H-chromene (DCM)-based near-infrared (NIR) fluorescent probe DCM-NO guided by theoretical calculation. The probe displayed excellent selectivity towards H2S with a fast response time (3 min) and low detection limit (fluorescence 25.3 nM/absorption 6.61 nM) in Hela cells and real water samples. Furthermore, the probe-doped solid sensing materials (test strips and nanofibrous films) exhibited specific visualization of H2S under ambient light or hand-held UV lamp, providing great potential for on-site and real-time application in environmental and biological systems.

5.
Sichuan Da Xue Xue Bao Yi Xue Ban ; 52(2): 300-305, 2021 Mar.
Artigo em Chinês | MEDLINE | ID: mdl-33829706

RESUMO

Objective: A predictive model of Alzheimer's disease (AD) was established based on brain surface meshes and geometric deep learning, and its performance was evaluated. Methods: Seventy-six clinically diagnosed AD patients and 83 healthy older adults were enrolled and randomly assigned to the training set and the test set according to a 4-to-1 ratio. Brain surface mesh was constructed from 3-D T1-weighted high-resolution structural MR volumes of each participant. After applying a series of simplification to the surface meshes, the training set was fed into the geometric deep neural network for training. The performance of the prediction model was evaluated with the test set, and the evaluation metrics included accuracy, sensitivity and specificity. Results: The prediction model trained on the right brain surface meshes with 6 000 faces achieved the best performance, with accuracy reaching 93.8%, sensitivity, 91.7%, and specificity, 94.1%. The evolution of the brain surface meshes during convolution and pooling revealed that AD patients had diffuse brain tissue loss compared with healthy older adults. Conclusion: Morphological brain analysis based on mesh data and geometric deep learning has great potential in the differential diagnosis of AD.


Assuntos
Doença de Alzheimer , Aprendizado Profundo , Idoso , Doença de Alzheimer/diagnóstico , Encéfalo/diagnóstico por imagem , Humanos , Imagem por Ressonância Magnética , Redes Neurais de Computação
6.
Food Chem ; 356: 129728, 2021 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-33836362

RESUMO

Alginate is a low-cost polysaccharide found abundantly in seaweeds which consists of mannuronate and guluronate, and it is considered a sustainable gum source for dietary fiber. To solve the high viscosity-related problems while retaining its physiological properties, four partially degraded alginate products (PDA1-4) with molecular weight of 1.05-0.40 × 105 g mol-1 and intrinsic viscosity of 170.9-38.9 mL g-1 were enzymatically prepared and characterized. 1H Nuclear magnetic resonance analysis showed the used alginate lyase had a preference to degrade guluronate-blocks. PDA1 and PDA2 presented random coil conformation, whereas PDA3 and PDA4 displayed compact spherical-coil conformation over random coil conformation in solution. In vitro assays suggested a glucose-adsorption capacity order of PDA1 < PDA2 < alginate < PDA3 < PDA4 and a glucose-diffusion retardation capacity order of PDA3 < PDA1 ≤ alginate < PDA2 < PDA4, indicating that partially degraded alginate reinforced the hypoglycemic effect, especially mannuronate-rich PDA4. Overall, the study may have important implications for development of PDA as dietary fiber with potential hypoglycemic activity.

7.
J Am Chem Soc ; 143(15): 5755-5762, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33843221

RESUMO

Discovery and optimization of new catalysts can be potentially accelerated by efficient data analysis using machine-learning (ML). In this paper, we record the process of searching for additives in the electrochemical deposition of Cu catalysts for CO2 reduction (CO2RR) using ML, which includes three iterative cycles: "experimental test; ML analysis; prediction and redesign". Cu catalysts are known for CO2RR to obtain a range of products including C1 (CO, HCOOH, CH4, CH3OH) and C2+ (C2H4, C2H6, C2H5OH, C3H7OH). Subtle changes in morphology and surface structure of the catalysts caused by additives in catalyst preparation can lead to dramatic shifts in CO2RR selectivity. After several ML cycles, we obtained catalysts selective for CO, HCOOH, and C2+ products. This catalyst discovery process highlights the potential of ML to accelerate material development by efficiently extracting information from a limited number of experimental data.

8.
Environ Sci Technol ; 55(8): 4638-4647, 2021 04 20.
Artigo em Inglês | MEDLINE | ID: mdl-33760589

RESUMO

Iron hydroxides are important scavengers for dissolved chromium (Cr) via coprecipitation processes; however, the influences of organic matter (OM) on Cr sequestration in Fe/Cr-OM ternary systems and the stability of the coprecipitates are not well understood. Here, Fe/Cr-OM coprecipitation was conducted at pH 3, and Cr hydroxide was undersaturated. Acetic acid (HAc), poly(acrylic acid) (PAA), and Suwannee River natural organic matter (SRNOM) were selected as model OMs, which showed different complexation capabilities with Fe/Cr ions and Fe/Cr hydroxide particles. HAc had no significant effect on the coprecipitation, as the monodentate carboxyl ligand in HAc did not favor complexation with dissolved Fe/Cr ions or Fe/Cr hydroxide nanoparticles. Contrarily, PAA and SRNOM with polydentate carboxyl ligand had strong complexation with Fe/Cr ions and Fe/Cr hydroxide nanoparticles, leading to significant amounts of PAA/SRNOM sequestered in the coprecipitates, which caused the structural disorder and fast aggregation of the coprecipitates. In comparison with that of PAA, preferential complexation of Cr ions with SRNOM resulted in higher Cr/Fe ratios in the coprecipitates. This study advances the fundamental understanding of Fe/Cr-OM coprecipitation and mechanisms controlling the composition and stability of the coprecipitates, which is essential for successful Cr remediation and removal in both natural and engineered settings.


Assuntos
Cromo , Hidróxidos , Compostos Férricos , Ferro
9.
Med Image Anal ; 70: 102006, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33690025

RESUMO

Cervical cancer causes the fourth most cancer-related deaths of women worldwide. Early detection of cervical intraepithelial neoplasia (CIN) can significantly increase the survival rate of patients. World Health Organization (WHO) divided the CIN into three grades (CIN1, CIN2 and CIN3). In clinical practice, different CIN grades require different treatments. Although existing studies proposed computer aided diagnosis (CAD) systems for cervical cancer diagnosis, most of them are fail to perform accurate separation between CIN1 and CIN2/3, due to the similar appearances under colposcopy. To boost the accuracy of CAD systems, we construct a colposcopic image dataset for GRAding cervical intraepithelial Neoplasia with fine-grained lesion Description (GRAND). The dataset consists of colposcopic images collected from 8,604 patients along with the pathological reports. Additionally, we invite the experienced colposcopist to annotate two main clues, which are usually adopted for clinical diagnosis of CIN grade, i.e., texture of acetowhite epithelium (TAE) and appearance of blood vessel (ABV). A multi-rater model using the annotated clues is benchmarked for our dataset. The proposed framework contains several sub-networks (raters) to exploit the fine-grained lesion features TAE and ABV, respectively, by contrastive learning and a backbone network to extract the global information from colposcopic images. A comprehensive experiment is conducted on our GRAND dataset. The experimental results demonstrate the benefit of using additional lesion descriptions (TAE and ABV), which increases the CIN grading accuracy by over 10%. Furthermore, we conduct a human-machine confrontation to evaluate the potential of the proposed benchmark framework for clinical applications. Particularly, three colposcopists on different professional levels (intern, in-service and professional) are invited to compete with our benchmark framework by investigating a same extra test set-our framework achieves a comparable CIN grading accuracy to that of a professional colposcopist.

10.
Res Dev Disabil ; 113: 103933, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33730685

RESUMO

BACKGROUND: Parental psychosocial factors are associated with emotional/behavioral problems in children with Autism Spectrum Disorder (ASD), but studies investigating their relationships are limited. AIMS: To explore the relationships between parents' perceived social support, parental resilience, parenting self-efficacy, and emotional/behavioral problems in children with ASD, and the mechanism underlying these relationships. METHOD: The participants were 289 parents of children with ASD (including fathers and mothers) in China. A survey comprising the Multidimensional Scale of Perceived Social Support, Resilience Scale, Parenting Sense of Competence Scale, and Strengths and Difficulties Questionnaire was administered. RESULTS: (1) Parents' perceived social support, parental resilience, and parenting self-efficacy were significantly associated with emotional/behavioral problems in children with ASD; (2) parental resilience and parenting self-efficacy were found to play a chain-mediating role in the association between perceived social support of parents and emotional/behavioral problems in children with ASD. CONCLUSION: It is crucial to improve parents' perceived social support, parental resilience, and parenting self-efficacy to reduce emotional/behavioral problems in children with ASD.

11.
J Optim Theory Appl ; : 1-23, 2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33678905

RESUMO

In this paper, we study robust necessary optimality conditions for a nondifferentiable complex fractional programming with uncertain data. A robust counterpart of uncertain complex fractional programming is introduced in the worst-case scenario. The concept of robust optimal solution of the uncertain complex fractional programming is introduced by using robust counterpart. We give an equivalence between the optimal solutions of the robust counterpart and a minimax nonfractional parametric programming. Finally, Fritz John-type and Karush-Kuhn-Tucker-type robust necessary optimality conditions of the uncertain complex fractional programming are established under some suitable conditions.

12.
Chemosphere ; 276: 130106, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33711795

RESUMO

Biomass-derived biochar is a carbon-rich product for soil amendment and sulfapyridine (SPY) is a typical sulfonamide of antibiotics in the soil. Amendment with biochar for soil could control SPY sorption or mobility. However, the pristine biochar inevitably goes through the long-term ageing in the environment and the information on such ageing impact on SPY sorption is not fully recognized. The simulated ageing process methods were employed for high-temperature and freeze-thraw climate to treat the biochar for two months in the present study. The batch adsorption of SPY and leaching column experiments were conducted for comparison of the fresh/aged biochar-soil system. The results showed that biochar addition could increase soil pH and saturated moisture, aged biochars own more O-containing functional groups and exhibit higher hydrophilicity and polarity. The sorption mechanism of unamended soil with SPY primarily resulted from the weak hydrophobic distribution. All fresh and aged biochar amended soil increased SPY sorption due to improvement of H-bonding interaction between SPY and biochar surface functional groups, indicating such initiative adsorption was stronger than passive partitioning. It is of importance for us to reconsider that aged biochar-amended soil, especially two-month high-temperature aged biochar-amended soil showed the highest adsorption performance and the lowest desorption capacity towards SPY. Both SPY leaching column experiments and the acid rain leaching tests suggested that the application of biochar in tropical or high-temperature climate regions for organics polluted soil remediation is favorable, but we should be aware of the uncertainty of soil amendment with biochar in cold regions.

13.
Neurotox Res ; 39(3): 851-859, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33538995

RESUMO

Diabetes is undoubtedly affecting global health. Considerable attention has been directed to brain complications caused by diabetes, which are reported to be related to the injury on brain microvascular endothelial cells. Oxidative stress and degradation of vascular basement membrane contribute to the injury of vascular endothelia by diabetes. The present study aims to investigate the effects of ropivacaine on high glucose-induced brain microvascular endothelial injury, as well as the underlying mechanism. Cell viability was determined by (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. The production of reactive oxygen species (ROS) was evaluated by 2',7'-dichlorodihydrofluorescein diacetate (DCFH-DA) staining. Quantitative real-time PCR (QRT-PCR) and enzyme-linked immunosorbent assay (ELISA) were used to determine the expression levels of matrix metalloproteinase-2 (MMP-2), matrix metalloproteinase-9 (MMP-9), intercellular cell adhesion molecule-1 (ICAM-1), and vascular endothelial growth factor (VEGF). The production of nitric oxide (NO) was detected by DAF-FM DA staining. The expression of inducible nitric oxide synthase (iNOS) was evaluated by qRT-PCR and Western blot analysis. Western blot was used to determine the expression of nuclear factor erythroid 2-related factor 2 (Nrf-2) and heme oxygenase 1 (HO-1).The cell viability of bEnd.3 brain endothelial cells was inhibited by high glucose, which was rescued by ropivacaine. The elevated production of ROS and MDA by high glucose was reversed by ropivacaine. Ropivacaine suppressed the expression of up-regulated iNOS, NO, MMP-2, MMP-9, ICAM-1, and VEGF induced by high glucose incubation. The expression of Nrf-2 and HO-1 by high glucose incubation was significantly inhibited by ropivacaine treatment.Ropivacaine might alleviate high glucose-induced brain microvascular endothelial injury by suppressing oxidative stress and down-regulating MMPs.

14.
Sci Total Environ ; 772: 145502, 2021 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-33581541

RESUMO

The conversion of agricultural biomass into hydrochar has enormous potential to improve soil quality. In particular, hydrochar particles introduced into the natural environment readily bind environmental pollutants. The interaction of hydrochar and pollutants will, however, be impacted by long term natural ageing in the earth surface. The adsorption performance and the associated mechanisms that could be affected by physical or chemical ageing are not yet fully understood. To elucidate the influence of different types ageing on the physicochemical properties and sorption capacity of hydrochar, we systematically characterized the elemental composition, specific surface area, total organic carbon, and functional groups of fresh and aged hydrochar. Norfloxacin (NOR), a typical antibiotic as a model in this study, was used for the sorption performance of different aged hydrochars in the presence or absence of Cu2+. The various artificial accelerated ageing methods have been employed such as H2O2 oxidation, HNO3/H2SO4 acidification, high temperature, and freeze-thaw cycles. The results showed that ageing could increase hydrochar polarity and surface functional groups, which both increased NOR hydrophobic partition and H-bonding interaction on hydrochars. The chemical ageing largely increased the abundance of CO than physical ageing. H-bonding dominated NOR sorption on hydrochars after acidification, high temperature, and freeze-thaw cycles. The hydrophobic partition was the main sorption mechanism of NOR on oxidative aged hydrochars. The coexisting Cu2+ inhibited NOR sorption on most aged hydrochars (acidification, high temperature, and freeze-thaw cycles), whereas specially for oxidative ageing, Cu2+ increased hydrophobic sorption sites on hydrochars surface and enhanced the sorption capacity for NOR. The results from this study are likely to reveal the mechanisms of pollutant adsorption on hydrochars and their different susceptibilities under various ageing environment, suggesting us to comprehensively consider the reciprocal effects of natural ageing and coexisting pollutants on a long-term use of hydrochar in the field.


Assuntos
Carvão Vegetal , Norfloxacino , Adsorção , Peróxido de Hidrogênio , Solo
15.
Nat Nanotechnol ; 16(3): 288-295, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33432205

RESUMO

Active matters are out-of-equilibrium systems that convert energy from the environment to mechanical motion. Non-reciprocal interaction between active matters may lead to collective intelligence beyond the capability of individuals. In nature, such emergent behaviours are ubiquitously observed in animal colonies, giving these species remarkable adaptive capability. In artificial systems, however, the emergence of non-trivial collective intelligent dynamics remains undiscovered. Here we show that a simple ion-exchange reaction can couple self-propelled ZnO nanorods and sulfonated polystyrene microbeads together. Chemical communication is established that enhances the reactivity and motion of both nanorods and the microbeads, resulting in the formation of an active swarm of nanorod-microbead complexes. We demonstrate that the swarm is capable of macroscopic phase segregation and intelligent consensus decision-making.

16.
Mol Neurobiol ; 58(5): 1990-2004, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33411316

RESUMO

Numerous evidences have highlighted the efficient role of dexmedetomidine (DEX) in multi-organ protection. In the present study, the neuroprotective role of DEX on cerebral ischemic injury and the underlining signaling mechanisms were explored. In order to simulate cerebral ischemic injury, we performed middle cerebral artery occlusion in mice and oxygen-glucose deprivation in neurons. Immunohistochemistry, Western blot analysis, and RT-qPCR were used to examine expression of HDAC5, NPAS4, MDM2, and PSD-95 in hippocampus tissues of MCAO mice and OGD-treated neurons. MCAO mice received treatment with DEX and sh-PSD-95, followed by neurological function evaluation, behavioral test, infarct volume detection by TTC staining, and apoptosis by TUNEL staining. Additionally, gain- and loss-of-function approaches were conducted in OGD-treated neuron after DEX treatment. Cell viability and apoptosis were assessed with the application of CCK-8 and flow cytometry. The interaction between MDM2 and PSD-95 was evaluated using Co-IP assay, followed by ubiquitination of PSD-95 detection. As per the results, HDAC5 and MDM2 were abundantly expressed, while NPAS4 and PSD-95 were poorly expressed in hippocampus tissues of MCAO mice and OGD-treated neurons. DEX elevated viability, and reduced LDH leakage rate and apoptosis rate of OGD-treated neurons, which was reversed following the overexpression of HDAC5. Moreover, HDAC5 augmented MDM2 expression via NPAS4 inhibition. MDM2 induced PSD-95 ubiquitination and degradation. In MCAO mice, DEX improved neurological function and behaviors and decreased infarct volume and apoptosis, which was negated as a result of PSD-95 silencing. DEX plays a neuroprotective role against cerebral ischemic injury by disrupting MDM2-induced PSD-95 ubiquitination and degradation via HDAC5 and NPAS4.

17.
Life Sci ; 269: 119038, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33453239

RESUMO

OBJECTIVE: Glucose-dependent insulinotropic polypeptide receptor (GIPR) has been identified as a contributor to obesity, and GIPR knockout mice are protected against diet-induced obesity (DIO). Therefore, we developed the anti-GIPR antagonistic monoclonal antibody (mAb) alone and in combination with DPP-4 inhibitor as potential therapeutic strategy for treating obesity and dyslipidemia based on this genetic evidence. METHODS: Fully neutralized GIPR activity of GIPR-monoclonal antibody (mAb) was assessed by regulating the in vitro production of cAMP in the mouse GIPR stably expressing cells. Chronic efficacies of GIPR-mAb alone and in combination with DPP-4 inhibitor Sitagliptin in diabetic or DIO mice were both investigated. Multiple metabolic parameters including body weight, glucose level, fat mass, lipid metabolism-related indicators as well as H&E staining and immunohistochemical analysis were performed. Role of GIPR in pancreatic cells on regulating fat metabolism was explored in GIPR ß-cell knockout mouse model. RESULTS: Chronic treatment of GIPR-mAb improved body weight control, glucose metabolism, and was associated with reduced fat mass, enhanced pancreatic function and exchange ratio of the resting respiratory in diabetic mice. In addition, further study of anti-GIPR mAb combined with Sitagliptin in DIO mice demonstrated significantly improved weight loss compare to the both monomer treatment. Furthermore, we demonstrated important role of GIPR in ß-cell in regulating the fat mass and response to antagonistic GIPR-mAb in a conditional GIPR-knockout mouse. CONCLUSION: Chronic treatment with anti-GIPR mAb alone and combined with DPP-4 inhibitor provide preclinical therapeutic approaches to treat obesity.


Assuntos
Anticorpos Monoclonais/farmacologia , Dipeptidil Peptidase 4/química , Inibidores da Dipeptidil Peptidase IV/farmacologia , Dislipidemias/tratamento farmacológico , Nefropatias/tratamento farmacológico , Obesidade/tratamento farmacológico , Receptores dos Hormônios Gastrointestinais/antagonistas & inibidores , Animais , Peso Corporal , Dieta Hiperlipídica/efeitos adversos , Quimioterapia Combinada , Dislipidemias/etiologia , Dislipidemias/patologia , Nefropatias/etiologia , Nefropatias/patologia , Masculino , Camundongos , Camundongos Knockout , Camundongos Obesos , Obesidade/etiologia , Obesidade/patologia , Receptores dos Hormônios Gastrointestinais/imunologia , Receptores dos Hormônios Gastrointestinais/fisiologia , Perda de Peso
18.
J Environ Sci (China) ; 100: 306-316, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33279044

RESUMO

Series of Fe/Cu-SSZ-13 catalysts with different Fe loading content were synthesized by simple one-pot strategy. The obtained catalysts were subjected to selective catalytic reduction (SCR) of NOx with NH3 and were characterized by various techniques. The results show that Fe0.63/Cu1.50-SSZ-13 catalyst with proper Fe content exhibits excellent catalytic activity with widest operation temperature window from 160 to 580°C, excellent hydrothermal stability as well as good resistance to sulfur poisoning when compared with Cu-SSZ-13, signifying its great potential for practical applications. Further characterizations reveal that the synthesized Fe/Cu-SSZ-13 catalysts present typical chabazite (CHA) structure with good crystallinity, while isolated Cu2+ and monomeric Fe3+ are revealed as the predominant copper and iron species. At low temperatures, isolated Cu2+ species act as primary active sites for SCR reaction, while monomeric Fe3+ species provide sufficient active sites for sustain the SCR activity at high temperature. Moreover, Fe over doping would lead to the damage of zeolite structure, destruction of isolated Cu2+ site, as well as the formation of highly oxidizing Fe2O3, thus causing deterioration of catalytic performances.


Assuntos
Amônia , Óxidos de Nitrogênio , Catálise , Óxido Nítrico , Oxirredução
19.
Life Sci ; : 118855, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33278392

RESUMO

AIMS: To investigate the therapeutic effects and potent mechanism of sinomenine (SIN) nanoliposomes on nephropathy in diabetic rats. MAIN METHODS: The protective efficacies of SIN on the oxidative injury in renal HK-2 cell induced by hydrogen peroxide (H2O2) were investigated via the CCK-8 assay. Forty SD rats with streptozotocin (STZ)-induced diabetic kidney disease (DKD) were assigned to the saline group and three SIN groups (10, 20 and 40 mg/kg). During 6-week treatment, body weight, fasting glucose level and other metabolic parameters were recorded. H&E staining and changes in renal functions as well as expression levels of apoptosis and fibrosis-related factors in renal tissues were assessed. The qPCR and western blotting (WB) methods were used to detect relative expression levels of JAK/STAT/SOCS pathway-related factors in the renal tissues. KEY FINDINGS: Cell viabilities of HK-2 cells with oxidative injury were obviously improved by incubating with SIN at 320 µg/mL for 92.9%. Significantly up-regulated GPX1, SOD2 and GSH contributed to the down-regulated ROS content in SIN-treated groups. Moreover, 6-week administration of SIN improved renal functions and worsening nephropathy morphology of DKD rats. SIN also ameliorated gradually increased renal cell apoptosis, suppressed expression levels of fibrosis-related proteins as well as IL-6 and ICAM-1, and regulated JAK2/STAT3/SOCS1 pathway, thereby exhibited protective effects on renal tissues of DKD rats. CONCLUSION: SIN protects nephrocytes and decreases renal tissue injury via inhibiting oxidative stress, reducing renal cell apoptosis and fibrosis, regulating the JAK2/STAT3/SOCS1 pathway in DKD rats.

20.
Nanotechnology ; 2020 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-33271517

RESUMO

By forming nanodisk (ND) structures on a blue-emitting InGaN/GaN quantum-well (QW) template, the QWs become close to the red-emitting quantum dots (QDs) and Ag nanoparticles (NPs) attached onto the sidewalls of the NDs such that Förster resonance energy transfer (FRET) and surface plasmon (SP) coupling can occur to enhance the efficiency of blue-to-red color conversion. With a larger ND height, more QWs are exposed to open air on the sidewall for more QD/Ag NP attachment through QD self-assembly and Ag NP drop casting such that the FRET and SP coupling effects, and hence the color conversion efficiency can be enhanced. A stronger FRET process leads to a longer QD photoluminescence (PL) decay time and a shorter QW PL decay time. It is shown that SP coupling can enhance the FRET efficiency.

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