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1.
Nano Lett ; 24(13): 4002-4011, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38525900

RESUMO

Empowering robots with tactile perception and even thinking as well as judgment capabilities similar to those of humans is an inevitable path for the development of future robots. Here, we propose a biomimetic electronic skin (BES) that truly serves and applies to robots to achieve superior dynamic-static perception and material cognition functionalities. First, the microstructured triboelectric and piezoresistive layers are fabricated by a facile template method followed by selected self-polymerization treatment, enabling BES with high sensitivity and a wide detection range. Further, through laminated-independent triboelectric and piezoresistive parts for perceiving dynamic and static pressures simultaneously, the BES is capable of supporting the robot hand to monitor the entire process during object grasping. Most importantly, by further combining a neural network model, an intelligent cognition system is constructed for real-time cognition of the object material species via one touch of the robot hand under arbitrary pressures, which goes beyond the human cognition ability.


Assuntos
Ácidos Alcanossulfônicos , Robótica , Dispositivos Eletrônicos Vestíveis , Humanos , Biomimética , Cognição , Percepção
2.
BMC Genomics ; 25(1): 468, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38745142

RESUMO

BACKGROUND: Plant-specific TIFY proteins are widely found in terrestrial plants and play important roles in plant adversity responses. Although the genome of loquat at the chromosome level has been published, studies on the TIFY family in loquat are lacking. Therefore, the EjTIFY gene family was bioinformatically analyzed by constructing a phylogenetic tree, chromosomal localization, gene structure, and adversity expression profiling in this study. RESULTS: Twenty-six EjTIFY genes were identified and categorized into four subfamilies (ZML, JAZ, PPD, and TIFY) based on their structural domains. Twenty-four EjTIFY genes were irregularly distributed on 11 of the 17 chromosomes, and the remaining two genes were distributed in fragments. We identified 15 covariate TIFY gene pairs in the loquat genome, 13 of which were involved in large-scale interchromosomal segmental duplication events, and two of which were involved in tandem duplication events. Many abiotic stress cis-elements were widely present in the promoter region. Analysis of the Ka/Ks ratio showed that the paralogous homologs of the EjTIFY family were mainly subjected to purifying selection. Analysis of the RNA-seq data revealed that a total of five differentially expressed genes (DEGs) were expressed in the shoots under gibberellin treatment, whereas only one gene was significantly differentially expressed in the leaves; under both low-temperature and high-temperature stresses, there were significantly differentially expressed genes, and the EjJAZ15 gene was significantly upregulated under both low- and high-temperature stress. RNA-seq and qRT-PCR expression analysis under salt stress conditions revealed that EjJAZ2, EjJAZ4, and EjJAZ9 responded to salt stress in loquat plants, which promoted resistance to salt stress through the JA pathway. The response model of the TIFY genes in the jasmonic acid pathway under salt stress in loquat was systematically summarized. CONCLUSIONS: These results provide a theoretical basis for exploring the characteristics and functions of additional EjTIFY genes in the future. This study also provides a theoretical basis for further research on breeding for salt stress resistance in loquat. RT-qPCR analysis revealed that the expression of one of the three EjTIFY genes increased and the expression of two decreased under salt stress conditions, suggesting that EjTIFY exhibited different expression patterns under salt stress conditions.


Assuntos
Eriobotrya , Regulação da Expressão Gênica de Plantas , Família Multigênica , Filogenia , Proteínas de Plantas , Estresse Fisiológico , Eriobotrya/genética , Estresse Fisiológico/genética , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica , Genoma de Planta , Cromossomos de Plantas/genética
3.
Appl Opt ; 63(5): 1217-1221, 2024 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-38437300

RESUMO

Wavelength-tunable orbital angular momentum (OAM) lasers with controllable topological charges have the potential for serving as light sources for large-capacity optical communication by combining conventional wavelength division multiplexing (WDM) with OAM mode-division multiplexing (OAM-MDM). In this study, we demonstrate a wavelength-tunable Tm-bulk laser that can control OAM states in the 2-µm spectral range. The excitation conditions for different Laguerre-Gaussian (L G 0,l ) modes in a bulk laser cavity are theoretically determined by measuring the spatial propagation dynamics of the annular pump beam. As a proof-of-principle study, we experimentally generate OAM states of |ℏ| and |2ℏ| from a T m:Y 2 O 3 ceramic laser with a tunable emission wavelength using a Lyot filter (LF). The spatial properties of the scalar optical vortices are well conserved during wavelength tuning, indicating the feasibility of our approach for producing wavelength-tunable structured light. These OAM laser sources, which are characterized by their robustness and compactness, have potential applications in various areas such as optical communications, quantum optics, super-resolution microscopes, and more.

4.
Appl Opt ; 63(4): 888-894, 2024 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-38437384

RESUMO

An electromagnetic wavefront can be flexibly manipulated by discrete phase coding on the coding unit. In this paper, we designed two coding metasurfaces with 1-bit and 3-bit based on active tuning of Dirac semimetals by controlling the Fermi level (E F) with an external polarization voltage. The size and structure of the metasurface remain unchanged with this strategy. Both designs were found to be dynamically tunable. The 1-bit coding metasurface enables beam conversion, single-focus switching, and switching between single-focus and multi-focus. On the other hand, the 3-bit coding metasurface enables the switching between vortex beams and single-beam mirror reflections. These proposed structures have potential applications in terahertz (THz) communications and terahertz-focused imaging, opening up new possibilities for the dynamic modulation of THz waves.

5.
Drug Dev Ind Pharm ; 50(5): 401-409, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38466185

RESUMO

OBJECTIVE: Magnolol (MG) and Brucea javanica (L.) Merr. oil (BJO) possess synergetic anti-tumor effects, but have poor water solubility and stability, which results in low oral bioavailability. SIGNIFICANCE: The MG loaded self-microemulsion drug delivery system (MG-SMDDS) with BJO as oil phase component was utilized to improve the cellular uptake and synergetic anti-tumor effects. METHODS: Compatibility study and pseudoternary phase diagram (PTPD) were respectively employed to screen for the composition and proportion of oil phase in the formulation. Central composite design-effect surface method was applied to optimize proportion of each formulation condition. The droplet size, ζ-potential, colloid stability, encapsulation rate (ER) and in vitro dissolution rate of MG-SMDDS were evaluated. Furthermore, cellular uptake and cytotoxicity of the microemulsion on HepG2 cells were assessed. RESULTS: The optimal composition of MG-SMDDS was: MG (9.09%), castor oil (7.40%), BJO (2.47%), Cremophor EL 35 (54.04%) and 1, 2-propanediol (27.01%). The MG-SMDDS exhibited satisfactory droplet size, ζ-potential, colloid stability and ER, as well as faster dissolution rate than free MG. More importantly, SMEDDS containing BJO could enhance the cellular uptake and cytotoxicity of free BJO and free MG on tumor cells. CONCLUSIONS: The BJO self-microemulsion delivery technique can provide an idea for design of oral delivery vehicles based on BJO.


Assuntos
Compostos de Bifenilo , Brucea , Sistemas de Liberação de Medicamentos , Emulsões , Lignanas , Óleos de Plantas , Solubilidade , Lignanas/administração & dosagem , Lignanas/farmacologia , Lignanas/farmacocinética , Lignanas/química , Humanos , Brucea/química , Compostos de Bifenilo/química , Células Hep G2 , Sistemas de Liberação de Medicamentos/métodos , Óleos de Plantas/química , Óleos de Plantas/farmacologia , Óleos de Plantas/administração & dosagem , Tamanho da Partícula , Disponibilidade Biológica , Antineoplásicos/administração & dosagem , Antineoplásicos/farmacologia , Antineoplásicos/química , Antineoplásicos/farmacocinética , Sobrevivência Celular/efeitos dos fármacos
6.
Opt Express ; 31(12): 19159-19172, 2023 Jun 05.
Artigo em Inglês | MEDLINE | ID: mdl-37381339

RESUMO

The polarization topology around the bound states in continuum (BIC) affects the optical vortex (OV) beam generation. We propose a cross-cross-shaped resonator based on a THz metasurface to realize an OV beam generator in real space by exploiting the inherent winding topology around the BIC. The BIC merging at the point Γ is achieved by tuning the width of the cross resonator, which significantly improves the Q factor and enhances the field localization. Furthermore, the switching between the high-order OV beam generator governed by the merged BIC and the low-order OV beam generator is realized. This extends the application of BIC in modulating orbital angular momentum.

7.
Opt Express ; 31(2): 2584-2592, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785268

RESUMO

Reduction of thermal effects is a challenging aspect for power scaling of 2.7-µm bulk Er-lasers due to the large quantum defect when pumping at ∼ 0.97 µm. Here, we demonstrate that thermal effects in an Er:Y2O3 ceramic laser can be significantly reduced pumping by an annular beam, thus improving the continuous-wave (CW) laser performance in the 3-µm spectral range. The excitation conditions of the TEM00 mode were determined theoretically by taking into account the propagation characteristics of the annular pump beam. For a comparison, the temperature and stress distributions are at first theoretically studied with three different pump configurations. In the experiment, output power of the Er:Y2O3 ceramic laser improved by ∼ 60% by changing the pump beam from coventional quasi-top-hat to a designed annular one. This work, as a proof-of-principle study, indicates the potential of power scaling of the 2.7-µm bulk Er-lasers pumping with an annular beam.

8.
Opt Lett ; 48(2): 510-513, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36638497

RESUMO

Pulses as short as 44 fs (6 optical cycles) with a spectral width of 120 nm are generated from a mode-locked solid-state laser near 2 µm employing an orthorhombic Tm:GdScO3 perovskite crystal. The average power amounts to 188 mW at a repetition rate of ∼77.6 MHz. The strong inhomogeneous line broadening in GdScO3 suggests optimum conditions for few-optical-cycle pulse generation of rare-earth ion doped GdScO3 bulk lasers.

9.
Phys Chem Chem Phys ; 25(8): 6510-6518, 2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36786281

RESUMO

Non-Hermitian metasurfaces provide an excellent platform for the study of parity-time (PT) symmetry transition. The exceptional point (EP) in the transition process exhibits peculiar physical phenomena and enriches the development of metasurfaces. In this study, a terahertz metal-graphene hybrid metasurface that can study PT symmetry transition and EP in transmission and reflection polarization channels is designed by using the phase transition characteristics of VO2. The tunable asymmetric loss and PT symmetry transition can be actively controlled by changing the Fermi energy of the graphene strip. Interestingly, owing to the special chirality of the structure, the original metasurface, and the mirrored metasurface degenerate into a circularly polarized state with opposite rotations at the same Fermi energy. The π-phase mutation at EP is observed following the interaction of circularly polarized waves and the metasurface and is expected to have good application prospects in environmental monitoring and gas sensing.

10.
Clin Lab ; 69(9)2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37702680

RESUMO

BACKGROUND: NeoSeq is a new method of gene sequencing for newborn screening. The goal is to explore the relationship between gene sequencing by NeoSeq combined with tandem mass spectrum (TMS) and four neonatal diseases. METHODS: A total of 1,989 newborns from August 2010 to December 2021 were enrolled. The case number of congenital hypothyroidism, phenylketonuria, adrenocortical hyperplasia, and glucose-6-phosphate dehydrogenase deficiency was counted, and the results of gene sequencing by NeoSeq and TMS were analyzed. RESULTS: The proportion of male newborns was higher than that of female newborns (51.68% vs. 48.32%). The detection rate of glucose-6-phosphate dehydrogenase deficiency was higher than that of the other three diseases (0.60% vs. 0.05%, 0.05%, 0.15%). A total of 121 newborns were recalled from 1989 newborns by traditional screening technique, and TMS detected phenylketonuria, citrullinemia, glutaric acidemia type I, and 3-methylcro-tonyl-CoA carboxylase deficiency in 1 newborn each. Gene sequencing by NeoSeq of newborns with positive TMS results confirmed the presence of susceptibility genes, and 17 of 1,868 newborns with normal biochemical tests had pathogenic genes. CONCLUSIONS: The incidence of glucose-6-phosphate dehydrogenase deficiency is relatively higher in four neonatal diseases, and the detection rate of gene sequencing by NeoSeq combined with TMS is high.


Assuntos
Erros Inatos do Metabolismo dos Aminoácidos , Deficiência de Glucosefosfato Desidrogenase , Doenças do Recém-Nascido , Fenilcetonúrias , Recém-Nascido , Feminino , Humanos , Masculino , Triagem Neonatal
11.
Appl Opt ; 62(13): 3502-3511, 2023 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-37132852

RESUMO

This paper proposes a deep-learning-assisted design method for 2-bit coding metasurfaces. This method uses a skip connection module and the idea of an attention mechanism in squeeze-and-excitation networks based on a fully connected network and a convolutional neural network. The accuracy limit of the basic model is further improved. The convergence ability of the model increased nearly 10 times, and the mean-square error loss function converges to 0.000168. The forward prediction accuracy of the deep-learning-assisted model is 98%, and the accuracy of inverse design results is 97%. This approach offers the advantages of an automatic design process, high efficiency, and low computational cost. It can serve users who lack metasurface design experience.

12.
Clin Exp Immunol ; 210(1): 39-52, 2022 10 21.
Artigo em Inglês | MEDLINE | ID: mdl-36001730

RESUMO

Increased expression of substance P (SP) and neurokinin-1 receptor (NK1R) has been noticed in patients with allergic rhinitis (AR) and allergic asthma (AA). However, little is known of the expression of SP and NK1R in monocytes and B cells of AR and AA. In the present study, the expression levels of SP and NK1R were determined by flow cytometry and mouse AR and AA models. The results showed that both percentages of SP+ monocytes and SP+ B cells, and mean fluorescence intensity (MFI) of SP in monocytes were elevated in the blood of AA and AR combined with AA (ARA) patients. Similarly, the percentages of NK1R+ monocytes were elevated in the blood of AR, AA, and ARA patients. Allergens Artemisia sieversiana wild allergen extract (ASWE), house dust mite extract (HDME), and Platanus pollen allergen extract (PPE) increased the expression density of SP molecules (determined by MFI) in an individual monocyte of AR patients. HDME and PPE appeared to enhance SP and NK1R expression in the B cells of ARA and AR patients. In the mouse AR and AA models, the percentages of NK1R+ monocytes and B cells were elevated in blood following OVA (ovalbumin) sensitization and challenge. Knocking out the FcεRI molecule completely abolished the OVA-induced upregulation of expression of NK1R in monocytes and B cells of AA mice. In conclusion, upregulated expressions of SP and NK1R may contribute to the pathogenesis of airway allergy.


Assuntos
Asma , Rinite Alérgica , Animais , Camundongos , Alérgenos , Monócitos/metabolismo , Ovalbumina , Receptores da Neurocinina-1/genética , Receptores da Neurocinina-1/metabolismo , Substância P/metabolismo , Substância P/farmacologia
13.
Opt Express ; 30(26): 46471-46486, 2022 Dec 19.
Artigo em Inglês | MEDLINE | ID: mdl-36558600

RESUMO

Herein, we propose an all dielectric, open-slit, U-shaped resonant arm-based metasurface that achieves three bound states in the continuum (BIC) in the high-frequency terahertz band whose quasi-BIC (QBIC) states can achieve Q factor of the magnitude order of 104. The maximum sensitivities of accidental QBIC and the figure-of-merit were respectively equal to 1717 GHz/RIU and 16670. Furthermore, the dependencies of the three QBICs on the THz incidence angle were different. Finally, the tunable sensor based on the Dirac semimetal metasurface achieves active tuning of the sensitivity and sensing range. This overcomes the shortcomings of the fixed structure without tuning capabilities, and provides a broad applicability platform for THz sensors.

14.
BMC Cancer ; 22(1): 1036, 2022 Oct 04.
Artigo em Inglês | MEDLINE | ID: mdl-36195857

RESUMO

BACKGROUND: The global burden of hepatocellular carcinoma (HCC) is increasing, negatively impacting social health and economies. The discovery of novel and valuable biomarkers for the early diagnosis and therapeutic guidance of HCC is urgently needed. METHODS: Extracellular matrix (ECM)-related gene sets, transcriptome data and mutation profiles were downloaded from the Matrisome Project and The Cancer Genome Atlas (TCGA)-LIHC datasets. Coexpression analysis was initially performed with the aim of identifying ECM-related lncRNAs (r > 0.4, p < 0.001). The screened lncRNAs were subjected to univariate analysis to obtain a series of prognosis-related lncRNA sets, which were incorporated into least absolute selection and shrinkage operator (LASSO) regression for signature establishment. Following the grouping of LIHC samples according to risk score, the correlations between the signature and clinicopathological, tumour immune infiltration, and mutational characteristics as well as therapeutic response were also analysed. lncRNA expression levels used for modelling were finally examined at the cellular and tissue levels by real-time PCR. All analyses were based on R software. RESULTS: AL031985.3 and MKLN1-AS were ultimately identified as signature-related lncRNAs, and both were significantly upregulated in HCC tissue samples and cell lines. The prognostic value of the signature reflected by the AUC value was superior to that of age, sex, grade and stage. Correlation analysis results demonstrated that high-risk groups exhibited significant enrichment of immune cells (DCs, macrophages and Tregs) and increased expression levels of all immune checkpoint genes. Prominent differences in clinicopathological profiles, immune functions, tumour mutation burden (TMB) and drug sensitivity were noted between the two risk groups. CONCLUSIONS: Our signature represents a valuable predictive tool in the prognostic management of HCC patients. Further validation of the mechanisms involved is needed.


Assuntos
Carcinoma Hepatocelular , Neoplasias Hepáticas , RNA Longo não Codificante , Biomarcadores Tumorais/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Matriz Extracelular/genética , Matriz Extracelular/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Prognóstico , RNA Longo não Codificante/metabolismo
15.
Phys Chem Chem Phys ; 24(41): 25571-25579, 2022 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-36254691

RESUMO

To synthesize dynamically tunable bound states in the continuum (BIC) metasurfaces in the terahertz (THz) band, in this study, a Dirac semimetal metasurface was designed for dynamic switching between THz-band BIC and quasi-BIC. We have simulated the designed metasurface, a symmetry-protected BIC with a quality factor (Q-factor) of 147 was achieved by breaking the symmetry of the structure, the variation law of the Q-factor with the asymmetry parameter was investigated, and the physical mechanism of quasi-BIC generation was determined by analyzing the surface electric field and surface current. Notably, the dynamic transition from BIC to quasi-BIC was achieved by varying the Fermi level of the Dirac semi-metal, with the maximum transmission difference of 0.61 and an almost constant resonant frequency for Fermi levels ranging from 2-20 meV. In addition, we fabricated and demonstrated a dynamic near-field display array, wherein different content is dynamically displayed by successively applying different gate voltages. This paper presents a novel design concept for dynamic switching between BIC and quasi-BIC on a metasurface and promotes the practical application of BIC metasurfaces.

16.
Small ; 17(41): e2100804, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34240560

RESUMO

Template methods are regarded as an important method for micro-nano processing in the active layer of flexible tactile sensors. These template methods use physical/chemical processes to introduce micro-nano structures on the active layer, which improves many properties including sensitivity, response/recovery time, and detection limit. However, since the processing process and applicable conditions of the template method have not yet formed a perfect system, the development and commercialization of flexible tactile sensors based on the template method are still at a relatively slow stage. Despite the above obstacles, advances in microelectronics, materials science, nanoscience, and other disciplines have laid the foundation for various template methods, enabling the continuous development of flexible tactile sensors. Therefore, a comprehensive and systematic review of flexible tactile sensors based on the template method is needed to further promote progress in this field. Here, the unique advantages and shortcomings of various template methods are summarized in detail and discuss the research progress and challenges in this field. It is believed that this review will have a significant impact on many fields of flexible electronics, which is beneficial to promote the cross-integration of multiple fields and accelerate the development of flexible electronic devices.


Assuntos
Eletrônica , Tato
17.
Scand J Immunol ; 93(3): e13003, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33247440

RESUMO

It was reported that the expression of Toll-like receptor (TLR) 9 may be related to Th2-type allergic inflammation including allergic rhinitis (AR). However, little is known about the expression of TLR9 in the basophils in AR. In the present study, the expression of TLR9 was examined by flow cytometry analysis, and the expression of TLR9 mRNA in KU812 was determined by quantitative real-time PCR. The results showed that the percentage of TLR9+ CCR3+ cells in blood granulocytes increased by 46% in patients with AR, but not in peripheral blood mononuclear cells (PBMCs). Allergens namely Dermatophagoide allergen extract (DAE) and Platanus pollen allergen extract (PPAE) upregulated the expression of TLR9 in CCR3+ granulocytes by 76% and 84%, respectively. DAE and PPAE also enhanced the proportions of TLR9+ CD123+ HLA-DR- cells and TLR9+ CCR3+ CD123+ HLA-DR- cells in granulocytes and PBMCs of patients with AR. In order to investigate the actions of allergens on basophils, KU812 cells were used. It was observed that all KU812 cells expressed TLR9, and the expression intensity of TLR9 in a single KU812 cell was elevated by CpG. IL-37, IL-31, IL-33, Artemisia sieversiana wild allergen extract (ASWAE), DAE, OVA and Der p 1 induced an increase in the expression of TLR9 mRNA and IL-6 production in KU812 cells. It was shown that the percentage of TLR9-expressing basophils increased in the blood of ovalbumin (OVA)-sensitized mice. In conclusion, an increased expression of TLR9 and the production of IL-6 in basophils implicate that the contribution of basophils to AR is likely via TLR9.


Assuntos
Basófilos/metabolismo , Pólen/imunologia , Pyroglyphidae/imunologia , Rinite Alérgica/imunologia , Receptor Toll-Like 9/metabolismo , Adulto , Alérgenos/imunologia , Animais , Linhagem Celular , Modelos Animais de Doenças , Feminino , Citometria de Fluxo , Regulação da Expressão Gênica , Granulócitos/metabolismo , Antígenos HLA-DR/imunologia , Humanos , Imunoglobulina E/sangue , Interleucina-13/metabolismo , Interleucina-6/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Pessoa de Meia-Idade , Ovalbumina/imunologia , RNA Mensageiro/biossíntese , Rinite Alérgica/patologia , Receptor Toll-Like 9/genética , Regulação para Cima/genética , Adulto Jovem
18.
Phys Rev Lett ; 126(22): 227402, 2021 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-34152189

RESUMO

As a newly emergent type-II Dirac semimetal, platinum telluride (PtTe_{2}) stands out from other two dimensional noble-transition-metal dichalcogenides for the unique band structure and novel physical properties, and has been studied extensively. However, the ultrafast response of low energy quasiparticle excitation in terahertz frequency remains nearly unexplored yet. Herein, we employ optical pump-terahertz probe (OPTP) spectroscopy to systematically study the photocarrier dynamics of PtTe_{2} thin films with varying pump fluence, temperature, and film thickness. Upon photoexcitation the terahertz photoconductivity (PC) of PtTe_{2} films shows abrupt increase initially, while the terahertz PC changes into negative value in a subpicosecond timescale, followed by a prolonged recovery process that lasted a few nanoseconds. The magnitude of both positive and negative terahertz PC response shows strongly pump fluence dependence. We assign the unusual negative terahertz PC to the formation of small polaron due to the strong electron-phonon (e-ph) coupling, which is further substantiated by temperature and film thickness dependent measurements. Moreover, our investigations give a subpicosecond timescale of simultaneous carrier cooling and polaron formation. The present study provides deep insights into the underlying dynamics evolution mechanisms of photocarrier in type-II Dirac semimetal upon photoexcitation, which is of crucial importance for designing PtTe_{2}-based optoelectronic devices.

19.
Molecules ; 26(11)2021 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-34073314

RESUMO

A high-quality Nd0.01:Gd0.89La0.1NbO4 (Nd:GLNO) crystal is grown by the Czochralski method, demonstrating wide absorption and fluorescence spectra and advantage for producing ultrafast laser pulses. In this paper, the tunable and passively mode-locking Nd:GLNO lasers are characterized for the first time. The tuning coverage is 34.87 nm ranging from 1058.05 to 1092.92 nm with a maximum output power of 4.6 W at 1065.29 nm. A stable continuous-wave (CW) passively mode-locking Nd:GLNO laser is achieved at 1065.26 nm, delivering a pulse width of 9.1 ps and a maximum CW mode-locking output power of 0.27 W.

20.
AAPS PharmSciTech ; 22(1): 45, 2021 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-33439366

RESUMO

This study aimed to develop a self-microemulsifying drug delivery system (SMEDDS) to enhance the solubility, oral bioavailability, and hypolipidemic effects of syringic acid (SA), a bioactive and poorly-soluble polyphenol. Based on the response surface methodology-central composite design (RSM-CCD), an optimum formulation of SA-SMEDDS, consisting of ethyl oleate (oil, 12.30%), Cremophor-EL (surfactant, 66.25%), 1,2-propanediol (cosurfactant, 21.44%), and drug loading (50 mg/g), was obtained. The droplets of SA-SMEDDS were nanosized (16.38 ± 0.12 nm), spherically shaped, and homogeneously distributed (PDI = 0.058 ± 0.013) nanoparticles with high encapsulation efficiency (98.04 ± 1.39%) and stability. In vitro release study demonstrated a prolonged and controlled release of SA from SMEDDS. In vitro cell studies signified that SA-SMEDDS droplets substantially promoted cellular internalization. In comparison with the SA suspension, SA-SMEDDS showed significant prolonged Tmax, t1/2, and MRT after oral administration. Also, SA-SMEDDS exhibited a delayed in vivo elimination, increased bioavailability (2.1-fold), and enhanced liver accumulation. Furthermore, SA-SMEDDS demonstrated significant improvement in alleviating serum lipid profiles and hepatic steatosis in high-fat diet-induced hyperlipidemia in mice. Collectively, SMEDDS demonstrated potential as a nanosystem for the oral delivery of SA with enhanced bioavailability and hypolipidemic effects.


Assuntos
Sistemas de Liberação de Medicamentos , Emulsões/administração & dosagem , Ácido Gálico/análogos & derivados , Hipolipemiantes/administração & dosagem , Administração Oral , Animais , Disponibilidade Biológica , Linhagem Celular , Liberação Controlada de Fármacos , Ácido Gálico/administração & dosagem , Ácido Gálico/farmacologia , Humanos , Hipolipemiantes/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Ratos , Ratos Sprague-Dawley , Tensoativos/química
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