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1.
Opt Express ; 32(12): 20483-20490, 2024 Jun 03.
Artigo em Inglês | MEDLINE | ID: mdl-38859429

RESUMO

A novel deep-ridge laser structure with atomic-layer deposition (ALD) sidewall passivation was proposed that enhances the optical characteristics of 8-µm ridge width III-nitride violet lasers on freestanding m-plane GaN substrates. The internal loss was determined using the variable stripe length method, where the laser structure with ALD sidewall passivation showed lower internal loss compared to the conventional shallow-ridge laser design. ALD sidewall passivation plays a critical role in device improvements; compared to the lasers without ALD sidewall passivation, the lasers with ALD sidewall passivation yield improved optoelectrical performance and longer lifetime under continuous-wave operation at high current density. This work demonstrates the importance of ALD sidewall passivation to laser performance, which enables high energy efficiency.

2.
J Stroke Cerebrovasc Dis ; 33(8): 107814, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38880364

RESUMO

AIMS: To investigate the association of the genetic predisposition of specific gut microbiotas with the clinical outcome of ischemic stroke. METHODS: We leveraged publicly available genome-wide association study (GWAS) data to perform Mendelian randomization (MR) analysis. The gut microbiota-related GWAS data from 18,340 individuals from the international consortium MiBioGen was used. The summary data for functional outcomes after ischemic stroke was obtained from the Genetics of Ischemic Stroke Functional Outcome (GISCOME) network meta-analysis. The primary outcomes were judged by the modified Rankin Scale (mRS). The principal analyses were conducted using the inverse-variance weighted (IVW) MR method. The Cochran's Q test, weighted median, MR-Egger regression, leave-one-SNP-out analysis, MR-Pleiotropy Residual Sum, and Outlier methods were adopted as sensitivity analyses. Furthermore, we performed bi-directional MR analysis and the MR Steiger directionality test to examine the direction of the causal relations. RESULTS: The results demonstrated that the genetic predisposition of genus Lactococcus, genus Ruminococcaceae NK4A214 group, family Peptostreptococcaceae, and genus Odoribacter was positively associated with favorable functional outcome after ischemic stroke. Genus Collinsella, genus Ruminococcaceae UCG005, genus Akkermansia, genus Eubacterium oxidoreducens group, and family Verrucomicrobiaceae were identified to be associated with worse functional outcomes after ischemic stroke. Our results showed no evidence of heterogeneity, directional pleiotropic effects, or collider bias, and the sensitivity of our analysis was acceptable. CONCLUSION: The genetic predisposition of different gut microbiotas was associated with the clinical outcome of ischemic stroke. Microbiota adjustment was a promising method to improve the clinical outcome of ischemic stroke.


Assuntos
Microbioma Gastrointestinal , Predisposição Genética para Doença , Estudo de Associação Genômica Ampla , AVC Isquêmico , Análise da Randomização Mendeliana , Humanos , Microbioma Gastrointestinal/genética , AVC Isquêmico/diagnóstico , AVC Isquêmico/genética , AVC Isquêmico/microbiologia , AVC Isquêmico/fisiopatologia , Fatores de Risco , Estado Funcional , Avaliação da Deficiência , Medição de Risco , Recuperação de Função Fisiológica , Bactérias/genética , Bactérias/isolamento & purificação , Eixo Encéfalo-Intestino , Polimorfismo de Nucleotídeo Único , Fenótipo , Resultado do Tratamento , Bases de Dados Genéticas , Disbiose
3.
Crit Rev Food Sci Nutr ; : 1-21, 2023 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-36971135

RESUMO

Seaweed polysaccharides (SPs) obtained from seaweeds are a class of functional prebiotics. SPs can regulate glucose and lipid anomalies, affect appetite, reduce inflammation and oxidative stress, and therefore have great potential for managing metabolic syndrome (MetS). SPs are poorly digested by the human gastrointestinal tract but are available to the gut microbiota to produce metabolites and exert a series of positive effects, which may be the mechanism by which SPs render their anti-MetS effects. This article reviews the potential of SPs as prebiotics in the management of MetS-related metabolic disturbances. The structure of SPs and studies related to the process of their degradation by gut bacteria and their therapeutic effects on MetS are highlighted. In summary, this review provides new perspectives on SPs as prebiotics to prevent and treat MetS.

4.
Acta Pharmacol Sin ; 44(5): 1038-1050, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36470978

RESUMO

Renal interstitial fibrosis is the common pathological process of various chronic kidney diseases to end-stage renal disease. Inhibition of fibroblast activation attenuates renal interstitial fibrosis. Our previous studies show that poricoic acid A (PAA) isolated from Poria cocos is a potent anti-fibrotic agent. In the present study we investigated the effects of PAA on renal fibroblast activation and interstitial fibrosis and the underlying mechanisms. Renal interstitial fibrosis was induced in rats or mice by unilateral ureteral obstruction (UUO). UUO rats were administered PAA (10 mg·kg-1·d-1, i.g.) for 1 or 2 weeks. An in vitro model of renal fibrosis was established in normal renal kidney fibroblasts (NRK-49F cells) treated with TGF-ß1. We showed that PAA treatment rescued Sirt3 expression, and significantly attenuated renal fibroblast activation and interstitial fibrosis in both the in vivo and in vitro models. In TGF-ß1-treated NRK-49F cells, we demonstrated that Sirt3 deacetylated ß-catenin (a key transcription factor of fibroblast activation) and then accelerated its ubiquitin-dependent degradation, thus suppressing the protein expression and promoter activity of pro-fibrotic downstream target genes (twist, snail1, MMP-7 and PAI-1) to alleviate fibroblast activation; the lysine-49 (K49) of ß-catenin was responsible for Sirt3-mediated ß-catenin deacetylation. In molecular docking analysis, we found the potential interaction of Sirt3 and PAA. In both in vivo and in vitro models, pharmacological activation of Sirt3 by PAA significantly suppressed renal fibroblast activation via facilitating ß-catenin K49 deacetylation. In UUO mice and NRK-49F cells, Sirt3 overexpression enhanced the anti-fibrotic effect of PAA, whereas Sirt3 knockdown weakened the effect. Taken together, PAA attenuates renal fibroblast activation and interstitial fibrosis by upregulating Sirt3 and inducing ß-catenin K49 deacetylation, highlighting Sirt3 functions as a promising therapeutic target of renal fibroblast activation and interstitial fibrosis.


Assuntos
Nefropatias , Sirtuína 3 , Triterpenos , beta Catenina , Animais , Camundongos , Ratos , beta Catenina/química , beta Catenina/metabolismo , Fibroblastos , Fibrose/tratamento farmacológico , Fibrose/patologia , Rim/patologia , Nefropatias/tratamento farmacológico , Nefropatias/patologia , Simulação de Acoplamento Molecular , Transdução de Sinais , Sirtuína 3/efeitos dos fármacos , Sirtuína 3/metabolismo , Fator de Crescimento Transformador beta1/metabolismo , Obstrução Ureteral/complicações , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/metabolismo , Triterpenos/farmacologia , Triterpenos/uso terapêutico
5.
BMC Med Inform Decis Mak ; 23(1): 209, 2023 10 10.
Artigo em Inglês | MEDLINE | ID: mdl-37817157

RESUMO

BACKGROUND: In the modern era of antibiotics, healthcare-associated infections (HAIs) have emerged as a prominent and concerning health threat worldwide. Implementing an electronic surveillance system for healthcare-associated infections offers the potential to not only alleviate the manual workload of clinical physicians in surveillance and reporting but also enhance patient safety and the overall quality of medical care. Despite the widespread adoption of healthcare-associated infections surveillance systems in numerous hospitals across China, several challenges persist. These encompass incomplete coverage of all infection types in the surveillance, lack of clarity in the alerting results provided by the system, and discrepancies in sensitivity and specificity that fall short of practical expectations. METHODS: We design and develop a knowledge-based healthcare-associated infections surveillance system (KBHAIS) with the primary goal of supporting clinicians in their surveillance of HAIs. The system operates by automatically extracting infection factors from both structured and unstructured electronic health data. Each patient visit is represented as a tuple list, which is then processed by the rule engine within KBHAIS. As a result, the system generates comprehensive warning results, encompassing infection site, infection diagnoses, infection time, and infection probability. These knowledge rules utilized by the rule engine are derived from infection-related clinical guidelines and the collective expertise of domain experts. RESULTS: We develop and evaluate our KBHAIS on a dataset of 106,769 samples collected from 84,839 patients at Gansu Provincial Hospital in China. The experimental results reveal that the system achieves a sensitivity rate surpassing 0.83, offering compelling evidence of its effectiveness and reliability. CONCLUSIONS: Our healthcare-associated infections surveillance system demonstrates its effectiveness in promptly alerting patients to healthcare-associated infections. Consequently, our system holds the potential to considerably diminish the occurrence of delayed and missed reporting of such infections, thereby bolstering patient safety and elevating the overall quality of healthcare delivery.


Assuntos
Infecção Hospitalar , Humanos , Reprodutibilidade dos Testes , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/prevenção & controle , Hospitais , China/epidemiologia
6.
Opt Express ; 30(2): 2759-2767, 2022 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-35209409

RESUMO

We report continuous wave operation of electrically injected InGaN laser diodes using nano-porous GaN n-side cladding with 33% porosity. At 454 nm emission wavelength, the pulsed injection slope efficiency is 0.24 W/A with a high loss of 82 cm-1. The considerable 60 cm-1 of excess loss of the nano-porous clad lasers is attributed to scattering at pores in unintentionally 3% porosified layers, supported by numerical modeling. Simulations comparing porous GaN cladding to AlInN cladding for lasers operating at 589 nm indicate that the porous cladding provides similar internal loss and lower thermal impedance.

7.
Opt Express ; 30(15): 27674-27682, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236933

RESUMO

GaN lasers with green emission wavelength at λ = 510 nm have been fabricated using novel nano-porous GaN cladding under pulsed electrical injection. The low slope efficiency of 0.13 W/A and high threshold current density of 14 kA/cm2 are related to a combination of poor injection efficiency and high loss, analyzed by the independent characterization methods of variable stripe length and segmented contacts. Continuous wave operation showed narrowed spectra and augmented spontaneous emission.

8.
Environ Toxicol ; 37(8): 2005-2018, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35475590

RESUMO

Inflammation is widely recognized as an essential inducer of epithelial-mesenchymal transition (EMT). Meanwhile, competitive endogenous RNA (ceRNA) has been involved in a variety of disease processes. Therefore, the aim of the current study is to explore the regulation of ceRNA in the PI3K/AKT pathway and EMT mechanism in inflammatory response caused by low molecular weight-polycyclic aromatic hydrocarbons (LMW-PAHs). The A549 cells were treated with an equal mixture of phenanthrene (Phe) and fluorene (Flu), and total RNA was extracted for transcriptome sequencing. The target regulation of ceRNA hsa_circ_0039929/hsa-miR-15b-3p_R-1/FGF2 was further determined for mechanism study. The mixture of Phe and Flu significantly upregulated the expressions of hsa_circ_0039929 and FGF2, down-regulated hsa-miR-15b-3p_R-1, activated the PI3K/AKT pathway and promoted EMT. Mechanically, the overexpression of hsa-miR-15b-3p_R-1 inhibited the expressions of hsa_circ_0039929 and FGF2, reversed the activation of PI3K/AKT signaling pathway by LMW-PAHs, and blocked the occurrence of EMT progression. Furthermore, knockdown of hsa_circ_0039929 could promote the levels of hsa-miR-15b-3p_R-1, while inhibit the expression of FGF2. The effects of hsa_circ_0039929 knockdowns on PI3K/AKT pathways and EMT progress resembled the hsa-miR-15b-3p_R-1 overexpression. All above suggested that ceRNA hsa_circ_0039929/hsa-miR-15b-3p_R-1/FGF2 played an important role in the inflammation and EMT caused by LMW-PAHs.


Assuntos
MicroRNAs , Hidrocarbonetos Policíclicos Aromáticos , Células A549 , Linhagem Celular Tumoral , Movimento Celular/genética , Proliferação de Células/genética , Transição Epitelial-Mesenquimal/genética , Fator 2 de Crescimento de Fibroblastos/metabolismo , Regulação Neoplásica da Expressão Gênica , Humanos , Inflamação/genética , MicroRNAs/genética , MicroRNAs/metabolismo , Peso Molecular , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , RNA Circular/genética
9.
J Asian Nat Prod Res ; 24(1): 76-87, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34937462

RESUMO

Renal fibrosis is a critical pathological process lead to a progressive loss of renal function. Jolkinolide B (JB) is a natural compound with anti-inflammatory activity from Euphorbia fischeriana Steud. The study evaluated the effect of JB on renal fibrosis in mice with unilateral ureteral obstruction (UUO). The results showed that JB could decrease renal fibrotic area, reduce phosphorylation of NF-κB p65 and the release of TNF-α, IL-6 and IL-1ß, restore the expression of vementin, α-SMA and E-cadherin, as well as TGF-ß1 and p-smad2/3. In conclusion, JB might reduce renal fibrosis by inhibiting inflammation induced by NF-κB pathway and EMT mediated by TGF-ß1/Smad pathway.


Assuntos
Obstrução Ureteral , Animais , Anti-Inflamatórios/farmacologia , Diterpenos , Transição Epitelial-Mesenquimal , Fibrose , Rim/patologia , Camundongos , Estrutura Molecular , Transdução de Sinais , Fator de Crescimento Transformador beta1/farmacologia , Fator de Crescimento Transformador beta1/uso terapêutico , Obstrução Ureteral/tratamento farmacológico , Obstrução Ureteral/patologia
10.
Opt Express ; 29(14): 22001-22007, 2021 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-34265974

RESUMO

In this work, we present fully transparent metal organic chemical vapor deposition (MOCVD)-grown InGaN cascaded micro-light-emitting diodes (µLEDs) with independent junction control. The cascaded µLEDs consisted of a blue emitting diode, a tunnel junction (TJ), a green emitting diode, and a TJ, without using any conductive oxide layer. We can control the injection of carriers into blue, green, and blue/green junctions in the same device independently, which show high optical and electrical performance. The forward voltage (Vf) at 20 A/cm2 for the TJ blue µLEDs and TJ green µLEDs is 4.06 and 3.13 V, respectively. These results demonstrate the efficient TJs and fully activated p-type GaN in the cascaded µLEDs. Such demonstration shows the important application of TJs for the integration of µLEDs with multiple color emissions.

11.
Opt Express ; 28(13): 18707-18712, 2020 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-32672165

RESUMO

High performance InGaN micro-size light-emitting diodes (µLEDs) with epitaxial tunnel junctions (TJs) were successfully demonstrated using selective area growth (SAG) by metalorganic chemical vapor deposition (MOCVD). Patterned n + GaN/n-GaN layers with small holes were grown on top of standard InGaN blue LEDs to form TJs using SAG. TJ µLEDs with squared mesa ranging from 10×10 to 100×100 µm2 were fabricated. The forward voltage (Vf) in the reference TJ µLEDs without SAG is very high and decreases linearly from 4.6 to 3.7 V at 20 A/cm2 with reduction in area from 10000 to 100 µm2, which is caused by the lateral out diffusion of hydrogen through sidewall. By contrast, the Vf at 20 A/cm2 in the TJ µLEDs utilizing SAG is significantly reduced to be 3.24 to 3.31 V. Moreover, the Vf in the SAG TJ µLEDs is independent on sizes, suggesting that the hydrogen is effectively removed through the holes on top of the p-GaN surface by SAG. The output power of SAG TJ µLEDs is ∼10% higher than the common µLEDs with indium tin oxide (ITO) contact.

12.
Opt Express ; 28(12): 18150-18159, 2020 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-32680016

RESUMO

We demonstrate InGaN-based semipolar 560 nm micro-light-emitting diodes with 2.5% EQE on high-quality and low-defect-density (20-21) GaN templates grown on scalable and low-cost sapphire substrates. Through transmission electron microscopy observations, we discuss how the management of misfit dislocations and their confinement in areas away from the active light-emitting region is necessary for improving device performance. We also discuss how the patterning of semipolar GaN on sapphire influences material properties in terms of surface roughness and undesired faceting in addition to indium segregation at the proximity of defected areas.

13.
Opt Express ; 28(9): 13569-13575, 2020 Apr 27.
Artigo em Inglês | MEDLINE | ID: mdl-32403828

RESUMO

We demonstrate a simple method to fabricate efficient, electrically driven, polarized, and phosphor-free white semipolar (20-21) InGaN light-emitting diodes (LEDs) by adopting a top blue quantum well (QW) and a bottom yellow QW directly grown on (20-21) semipolar bulk GaN substrate. At an injection current of 20 mA, the fabricated 0.1 mm2 size regular LEDs show an output power of 0.9 mW tested on wafer without any backside roughing, a forward voltage of 3.1 V and two emission peaks located at 427 and 560 nm. A high polarization ratio of 0.40 was measured in the semipolar monolithic white LEDs, making them promising candidates for backlighting sources in liquid crystal displays (LCDs). Furthermore, a 3dB modulation bandwidth of 410 MHz in visible light communication (VLC) was obtained in the micro-size LEDs (µLEDs) with a size of 20×20 µm2 and 40×40 µm2, which could overcome the limitation of slow frequency response of yellow phosphor in commercial white LEDs combing blue LEDs and yellow phosphor.

14.
Opt Lett ; 45(20): 5844-5847, 2020 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-33057299

RESUMO

Single-frequency blue laser sources are of interest for an increasing number of emerging applications but are still difficult to implement and expensive to fabricate and suffer from poor robustness. Here a novel and universal grating design to realize distributed optical feedback in visible semiconductor laser diodes (LDs) was demonstrated on a semipolar InGaN LD, and its unique effect on the laser performance was investigated. For the first time, to the best of our knowledge, a low threshold voltage, record-high power output, and ultra-narrow single-mode lasing were simultaneously obtained on the new laser structure with a thinner p-GaN layer and a third-order phase-shifted embedded dielectric grating. Under continuous-wave operation, such 450 nm lasers achieved 35 dB side-mode suppression ratio, less than 2 pm FWHM, and near 400 mW total output power at room temperature.

15.
Environ Toxicol ; 35(1): 37-46, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31456356

RESUMO

Phenanthrene (Phe) female rat model was established to explore the effects of Phe on oxidative stress and inflammation. The rats were randomly divided into three groups including control (C), low (L), and high (H) group. Phe was supplied to L and H groups at the dosage of 180 mg/kg and 900 mg/kg orally at first day, and with the dose 90 mg/kg and 450 mg/kg by intraperitoneal injection at the last 2 days. The C group was enriched with the same volume of corn oil. The blood, lung, and liver tissues were collected. The superoxide dismutase (SOD), malonaldehyde (MDA), and 8-hydroxy-2-deoxyguanosine (8-OHdG) were detected to evaluate oxidative stress. The protein and mRNA expressions of interleukin 6 (IL-6), tumor necrosis factor-α (TNF-α), transforming growth factor-ß (TGF-ß), and interleukin 10 (IL-10) were detected to evaluate inflammation. Further, the forkhead box transcription factor 3 (Foxp3) was analyzed to hint the injury mechanism of inflammation. The results showed SOD and MDA in lung and liver, and serum 8-OHdG elevated significantly in H groups (P < .05). Meanwhile, there were significant increases in the protein and mRNA expression of TNF-α and IL-6 in lung and liver of H groups (P < .05). In addition, the protein and mRNA expressions of TGF-ß and Foxp3 were all decreased significantly in both lung and liver of H groups (P < .05). Results demonstrated that an obvious change of Phe exposure could induce oxidative stress and inflammation in female rats. This is a first pilot study to explore the association between Phe exposure and oxidative stress and inflammation using a female rat model.


Assuntos
Poluentes Atmosféricos/toxicidade , Fígado/efeitos dos fármacos , Pulmão/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Estresse Oxidativo/imunologia , Fenantrenos/toxicidade , Animais , Citocinas/sangue , Citocinas/imunologia , Relação Dose-Resposta a Droga , Feminino , Fígado/imunologia , Fígado/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Projetos Piloto , Distribuição Aleatória , Ratos , Ratos Wistar
16.
Sensors (Basel) ; 20(20)2020 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-33053700

RESUMO

Most Internet of Things (IoT) systems are based on the wireless sensor network (WSN) due to the reduction of the cable layout cost. However, the battery life of nodes is a key issue when the node is powered by a battery. A Low-Power WSN Protocol with ADR and TP Hybrid Control is proposed in this paper to improve battery life significantly. Besides, techniques including the Sub-1GHz star topology network with Time Division Multiple Access (TDMA), adaptive data rate (ADR), and transmission power control (TPC) are also used. The long-term testing results show that the nodes with the proposed algorithm can balance the communication quality and low power consumption simultaneously. The experimental results also show that the power consumption of the node with the algorithm was reduced by 38.46-54.44% compared with the control group. If using AAA battery with 1200 mAh, the node could run approximately 4.2 years with the proposed hybrid control algorithm with an acquisition period of under 5 s.

18.
BMC Plant Biol ; 19(1): 589, 2019 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-31881837

RESUMO

BACKGROUND: Short internodes contribute to plant dwarfism, which is exceedingly beneficial for crop production. However, the underlying mechanisms of internode elongation are complicated and have been not fully understood. RESULTS: Here, we report a maize dwarf mutant, dwarf2014 (d2014), which displays shortened lower internodes. Map-based cloning revealed that the d2014 gene is a novel br2 allele with a splicing variation, resulting in a higher expression of BR2-T02 instead of normal BR2-T01. Then, we found that the internode elongation in d2014/br2 exhibited a pattern of inhibition-normality-inhibition (transient for the ear-internode), correspondingly, at the 6-leaf, 12-leaf and 14-leaf stages. Indeed, BR2 encodes a P-glycoprotein1 (PGP1) protein that functions in auxin efflux, and our in situ hybridization assay showed that BR2 was mainly expressed in vascular bundles of the node and internode. Furthermore, significantly higher auxin concentration was detected in the stem apex of d2014 at the 6-leaf stage and strictly in the node region for the ear-internode at the 14-leaf stage. In such context, we propose that BR2/PGP1 transports auxin from node to internode through the vascular bundles, and excessive auxin accumulation in the node (immediately next to the intercalary meristem) region suppresses internode elongation of d2014. CONCLUSIONS: These findings suggest that low auxin levels mediated by BR2/PGP1 in the intercalary meristem region are crucial for internode elongation.


Assuntos
Ácidos Indolacéticos/metabolismo , Meristema/metabolismo , Proteínas de Plantas/fisiologia , Zea mays/crescimento & desenvolvimento , Subfamília B de Transportador de Cassetes de Ligação de ATP/fisiologia , Alelos , Transporte Biológico , Isoformas de Proteínas , Zea mays/genética , Zea mays/metabolismo
19.
Mol Genet Genomics ; 294(2): 501-517, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30607602

RESUMO

MicroRNA164 (miR164) plays a key role in leaf and flower development, lateral root initiation, and stress responses. However, little is known about the regulatory roles of miR164 during seed development, particularly in maize. The aim of this study was to discover the developmental function of miR164 in maize seed. Small RNA sequencing (sRNA-seq) was performed at two key stages. The results indicated that miR164 was down-regulated during maize seed development. In addition, degradome library sequencing and transient expression assays identified the target genes for miR164. Two microRNA (miRNA) pairs, miR164-NAM, ATAF, and CUC32 (NAC32) and miR164-NAC40, were isolated. The developmental function of miR164 was determined by analyzing the differentially expressed genes (DEGs) between the wild-type and miR164 transgenic lines using RNA sequencing (RNA-seq) and by screening the DEGs related to NAC32 and NAC40 via co-expression and transient expression analysis. These results identified two beta-expansin genes, EXPB14 and EXPB15, which were located downstream of the NAC32 and NAC40 genes. This study revealed, for the first time, a miR164-dependent regulatory pathway, miR164-NAC32/NAC40-EXPB14/EXPB15, which participates in maize seed expansion. These findings highlight the significance of miR164 in maize seed development, and can be used to explore the role of miRNA in seed development.


Assuntos
MicroRNAs/genética , Raízes de Plantas/genética , Sementes/genética , Zea mays/genética , Arabidopsis/genética , Arabidopsis/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas , Redes Reguladoras de Genes , Folhas de Planta/genética , Folhas de Planta/crescimento & desenvolvimento , Proteínas de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Plantas Geneticamente Modificadas , Sementes/crescimento & desenvolvimento , Análise de Sequência de RNA , Zea mays/crescimento & desenvolvimento
20.
Opt Express ; 27(17): 24154-24160, 2019 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-31510309

RESUMO

We investigated the electrical and optical performances of semipolar (11-22) InGaN green µLEDs with a size ranging from 20 × 20 µm2 to 100 × 100 µm2, grown on a low defect density and large area (11-22) GaN template on patterned sapphire substrate. Atom probe tomography (APT) gave insights on quantum wells (QWs) thickness and indium composition and indicated that no indium clusters were observed in the QWs. The µLEDs showed a small wavelength blueshift of 5 nm, as the current density increased from 5 to 90 A/cm2 and exhibited a size-independent EQE of 2% by sidewall passivation using atomic-layer deposition, followed by an extremely low leakage current of ~0.1 nA at -5 V. Moreover, optical polarization behavior with a polarization ratio of 40% was observed. This work demonstrated long-wavelength µLEDs fabricated on semipolar GaN grown on foreign substrate, which are applicable for a variety of display applications at a low cost.

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