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1.
Opt Express ; 31(2): 1269-1281, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785166

RESUMO

Active manipulation of terahertz (THz) beam deflection and intensity is highly desired for possible applications in wireless communication, radar, and remote sensing. Here, by integrating the phase-gradient metasurfaces and tunable liquid crystal materials, we demonstrate an active THz beam deflection device based on polarization mode conversion. The resonant modes in the photonic cavity formed by the double-layer metasurface and the tunable anisotropic liquid crystal material in the cavity not only improve the polarization conversion efficiency of the device, but also actively regulate the resonance matching conditions. As a consequence, a beam deflection of 47.5° with 50% diffraction intensity at 0.69 THz is achieved in the x-to-y polarization conversion mode, and this beam can be actively modulated with an ultrahigh modulation depth of 99.6% by rotating the anisotropic optical axis of liquid crystals. Moreover, the proposed device can also work as the deflection of 32.5° in the y-to-x polarization conversion mode at 0.94 THz with a maximum diffraction intensity of 38% and an intensity modulation depth of 97.8%. This work provides a new approach based on liquid crystal photonic devices for wavefront manipulation and active modulation for THz waves.

2.
Opt Lett ; 48(7): 1682-1685, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-37221740

RESUMO

We experimentally demonstrate a dynamic terahertz (THz) chiral device based on a composite structure of anisotropic liquid crystals (LCs) sandwiched between a bilayer metasurface. The device supports the symmetric mode and antisymmetric mode under the incidence of left- and right-circular polarized waves, respectively. The different coupling strengths of the two modes reflect the chirality of the device, and the anisotropy of the LCs can change the coupling strength of the modes, which brings tunability to the chirality of the device. The experimental results show that the circular dichroism of the device can be dynamically controlled from 28 dB to -32 dB (i.e., inversion regulation) at approximately 0.47 THz and from -32 dB to 1 dB (i.e., switching regulation) at approximately 0.97 THz. Moreover, the polarization state of the output wave is also tunable. Such flexible and dynamic manipulation of THz chirality and polarization might build an alternative pathway for complex THz chirality control, high-sensitivity THz chirality detection, and THz chiral sensing.

3.
Entropy (Basel) ; 24(12)2022 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-36554209

RESUMO

In recent years, protecting important objects by simulating animal camouflage has been widely employed in many fields. Therefore, camouflaged object detection (COD) technology has emerged. COD is more difficult to achieve than traditional object detection techniques due to the high degree of fusion of objects camouflaged with the background. In this paper, we strive to more accurately and efficiently identify camouflaged objects. Inspired by the use of magnifiers to search for hidden objects in pictures, we propose a COD network that simulates the observation effect of a magnifier called the MAGnifier Network (MAGNet). Specifically, our MAGNet contains two parallel modules: the ergodic magnification module (EMM) and the attention focus module (AFM). The EMM is designed to mimic the process of a magnifier enlarging an image, and AFM is used to simulate the observation process in which human attention is highly focused on a particular region. The two sets of output camouflaged object maps were merged to simulate the observation of an object by a magnifier. In addition, a weighted key point area perception loss function, which is more applicable to COD, was designed based on two modules to give greater attention to the camouflaged object. Extensive experiments demonstrate that compared with 19 cutting-edge detection models, MAGNet can achieve the best comprehensive effect on eight evaluation metrics in the public COD dataset. Additionally, compared to other COD methods, MAGNet has lower computational complexity and faster segmentation. We also validated the model's generalization ability on a military camouflaged object dataset constructed in-house. Finally, we experimentally explored some extended applications of COD.

4.
J Sep Sci ; 42(22): 3451-3458, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31512367

RESUMO

Glucose-derived carbon-decorated magnetic microspheres were synthesized by an easy hydrothermal carbonization method and used as a high-efficiency adsorbent to extract bisphenols in water and tea drinks. The as-prepared carbon-decorated magnetic microspheres had a well-defined core-shell structure with a shell thickness of about 5 nm. The microspheres possessed high saturation magnetization at 60.8 emu/g and excellent chemical stability in aqueous solution. The experimental parameters affecting the extraction efficiency, including extraction time, pH, adsorbent dosage, desorption solvents, desorption time, and solution volume were evaluated. Electrostatic and π-π interactions were the major driving forces during extraction. Overall, a new magnetic solid-phase extraction method of determining bisphenols was developed on the basis of as-prepared magnetic microspheres. The method had a wide linear range, low limits of detection (0.03-0.10 µg/L), and high recoveries (85.4-104.6%).


Assuntos
Compostos Benzidrílicos/isolamento & purificação , Carbono/química , Água Potável/química , Glucose/química , Fenóis/isolamento & purificação , Chá/química , Poluentes Químicos da Água/isolamento & purificação , Adsorção , Compostos Benzidrílicos/química , Concentração de Íons de Hidrogênio , Campos Magnéticos , Microesferas , Fenóis/química , Poluentes Químicos da Água/química
5.
Genes (Basel) ; 15(8)2024 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-39202436

RESUMO

This study investigated the transcriptomic mechanisms underlying melatonin accumulation and the enhancement of salt tolerance in hull-less barley seeds subjected to zinc sulphate stress. Following zinc sulphate treatment, hull-less barley seeds demonstrated increased melatonin accumulation and improved salt tolerance. Through transcriptome analysis, the study compared gene expression alterations in seeds (using the first letter of seed, this group is marked as 'S'), seeds treated with pure water (as the control group, is marked as 'C'), and germinated seeds exposed to varying concentrations of zinc sulphate (0.2 mM and 0.8 mM, the first letter of zinc sulphate, 'Z', is used to mark groups 'Z1' and 'Z2'). The analysis revealed that 8176, 759, and 622 differentially expressed genes (DEGs) were identified in the three comparison groups S.vs.C, C.vs.Z1, and C.vs.Z2, respectively. Most of the DEGs were closely associated with biological processes, including oxidative-stress response, secondary metabolite biosynthesis, and plant hormone signaling. Notably, zinc sulphate stress influenced the expression levels of Tryptophan decarboxylase 1 (TDC1), Acetylserotonin O-methyltransferase 1 (ASMT1), and Serotonin N-acetyltransferase 2 (SNAT2), which are key genes involved in melatonin synthesis. Furthermore, the expression changes of genes such as Probable WRKY transcription factor 75 (WRKY75) and Ethylene-responsive transcription factor ERF13 (EFR13) exhibited a strong correlation with fluctuations in melatonin content. These findings contribute to our understanding of the mechanisms underlying melatonin enrichment in response to zinc sulphate stress.


Assuntos
Regulação da Expressão Gênica de Plantas , Hordeum , Melatonina , Proteínas de Plantas , Transcriptoma , Sulfato de Zinco , Melatonina/farmacologia , Melatonina/biossíntese , Hordeum/genética , Hordeum/efeitos dos fármacos , Hordeum/metabolismo , Hordeum/crescimento & desenvolvimento , Regulação da Expressão Gênica de Plantas/efeitos dos fármacos , Sulfato de Zinco/farmacologia , Transcriptoma/efeitos dos fármacos , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Perfilação da Expressão Gênica/métodos , Sementes/genética , Sementes/efeitos dos fármacos , Sementes/crescimento & desenvolvimento , Sementes/metabolismo , Germinação/efeitos dos fármacos , Germinação/genética , Tolerância ao Sal/genética
6.
Sci Rep ; 13(1): 22894, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-38129488

RESUMO

Osteoarthritis (OA) is a progressive cartilage degradation disease, concomitant with synovitis, osteophyte formation, and subchondral bone sclerosis. Over 37% of the elderly population is affected by OA, and the number of cases is increasing as the global population ages. Therefore, the objective of this study was to identify and analyze the hub genes of OA combining with comprehensive bioinformatics analysis tools to provide theoretical basis in further OA effective therapies. Two sample sets of GSE46750 contained 12 pairs OA synovial membrane and normal samples harvested from patients as well as GSE98918 including 12 OA and non-OA patients were downloaded from the Gene Expression Omnibus database (GEO) database. Differentially expressed genes (DEGs) were identified using Gene Expression Omnibus 2R (GEO2R), followed by functional enrichment analysis, protein-protein interaction networks construction. The hub genes were identified and evaluated. An OA rat model was constructed, hematoxylin and eosin staining, safranin O/fast green staining, cytokines concentrations of serum were used to verify the model. The hub genes expression level in the knee OA samples were verified using RT-qPCR. The top 20 significantly up-regulated and down-regulated DEGs were screened out from the two datasets, respectively. The top 18 GO terms and 10 KEGG pathways were enriched. Eight hub genes were identified, namely MS4A6A, C1QB, C1QC, CD74, CSF1R, HLA-DPA1, HLA-DRA and ITGB2. Among them, the hub genes were all up-regulated in in vivo OA rat model, compared with healthy controls. The eight hub genes identified (MS4A6A, C1QB, C1QC, CD74, CSF1R, HLA-DPA1, HLA-DRA and ITGB2) were shown to be associated with OA. These genes can serve as disease markers to discriminate OA patients from healthy controls.


Assuntos
Redes Reguladoras de Genes , Osteoartrite do Joelho , Humanos , Idoso , Animais , Ratos , Prognóstico , Cadeias alfa de HLA-DR , Biologia Computacional , Biomarcadores , Perfilação da Expressão Gênica
7.
J Back Musculoskelet Rehabil ; 36(2): 323-329, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36155499

RESUMO

BACKGROUND: According to reports in the literature, osteoporotic vertebral compression fracture (OVCF) is associated with paraspinal muscle degeneration; however, the association between the severity of OVCF and paraspinal muscle degeneration is not clear. OBJECTIVE: The purpose of this study was to investigate the association between paraspinal muscle degeneration and OVCF severity in postmenopausal women. METHODS: Three hundred and seventy-six MRI images from 47 patients were collected and analyzed. Sagittal and axial coronal T2-weighted images were used to measure the fractured vertebra sagittal cross-sectional area (FSCSA), the adjacent normal vertebral body sagittal cross-sectional area (NSCSA), paraspinal muscle cross-sectional area (CSA), and the fat cross-sectional area (FCSA). The ratio of fractured vertebra compressed sagittal cross-sectional area (RCSA) and fatty infiltration ratio (FIR) was subsequently calculated. The formulas for RCSA and FIR calculations are as follows: RCSA = (NSCSA-FSCSA)/NSCSA; FIR = FCSA/CSA. RCSA and FIR represent the severity of OVCF and paraspinal muscle degeneration, respectively. RESULTS: The correlation between paraspinal muscle degeneration and OVCF severity was analyzed using the Pearson correlation, and multiple regression analysis was performed to explore related risk factors. OVCF severity was closely associated with paraspinal muscle degeneration (L3/4 FIR r= 0.704, P< 0.05; L4/5 FIR r= 0.578, P< 0.05; L5/S1 FIR r= 0.581, P< 0.05). Multiple regression analysis demonstrated that the risk factor for OVCF severity was L3/4 FIR (ß= 0.421, P= 0.033). CONCLUSION: OVCF severity was associated with the FIR of paraspinal muscles, and L3/4 FIR was a predictive factor for OVCF severity in postmenopausal women.


Assuntos
Fraturas por Compressão , Fraturas da Coluna Vertebral , Humanos , Feminino , Fraturas por Compressão/diagnóstico por imagem , Músculos Paraespinais/diagnóstico por imagem , Músculos Paraespinais/patologia , Pós-Menopausa , Fraturas da Coluna Vertebral/diagnóstico por imagem , Fraturas da Coluna Vertebral/patologia , Atrofia Muscular , Vértebras Lombares , Imageamento por Ressonância Magnética/métodos , Estudos Retrospectivos
8.
Front Oncol ; 12: 891623, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35785206

RESUMO

Purpose: The aim of this study is to investigate the trends in incidence and mortality, and explore any change in survival of penile cancer in the United States. Methods: We obtained data from the Surveillance, Epidemiology, and End Results (SEER) database (2000-2018) utilizing the SEER Stat software. The joinpoint regression was used to analyze the secular trend of incidence and incidence-based mortality (IBM) stratified by age, race, and summary stage. The 5-year relative survival rate was also calculated. Result: The age-adjusted rates of penile cancer patients were 0.38 (0.37-0.39) and 0.21 (0.2-0.21) for overall incidence and IBM, respectively. The 5-year relative survival rates were 67.7%, 66.99%, and 65.67% for the calendar periods of 2000-2004, 2005-2009, and 2010-2014, respectively. No significant changes in incidence by era were observed from 2000 to 2018 [annual percentage change (APC) = 0.5%, p = 0.064]. The IBM rate of penile cancer showed an initial significant increase from 2000 to 2002 (APC = 78.6%, 95% CI, -1.7-224.6) followed by a deceleration rate of 4.6% (95% CI, 3.9-5.3) during 2002 to 2018. No significant improvement in 5-year relative survival was observed. The trends by age, race, and summary stage in incidence and IBM were significantly different. Conclusion: This study, using population-level data from the SEER database, showed an increasing trend in IBM and no significant improvement in the 5-year relative survival rate. Meanwhile, the incidence of penile cancer exhibited a relatively stable trend during the study period. These results might be due to the lack of significant progress in the treatment and management of penile cancer patients in the United States in recent decades. More efforts, like increasing awareness among the general population and doctors, and centralized management, might be needed in the future to improve the survival of this rare disease.

9.
Water Res ; 199: 117195, 2021 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-33984585

RESUMO

With the linkage between dissolved organic matter (DOM) and the characteristics of natural ecosystem assessed extensively, the properties of DOM in reservoirs, the typical human interrupted ecosystems, have been focused on in recent years, which is critical for the understanding of human impacts on watershed ecosystems and carbon cycling. This study aims to analyze the effect of hydrological management on the DOM chemistry and organic carbon burial in Daning River tributary of the world's largest Three Gorges Reservoir (TGR). Based on the application of a combined approach including bulk geochemical analyses, optical spectroscopy, and ultrahigh-resolution Fourier transform ion cyclotron resonance mass spectrometry, various sources of DOM (terrestrial, anthropogenic, and autochthonous sources) were revealed. An increasing trend of terrestrial and recalcitrant DOM was observed along the upstream to downstream transect of Daning River tributary, which was mainly caused by the water intrusion with a higher terrestrial and recalcitrant signature from mainstream to tributary resulted from hydrological management of TGR. Integrated with the analysis of sedimentary organic matter in Daning River tributary in the past decade (after the construction of TGR), our work suggests that organic carbon burial in the reservoir could be enhanced by hydrological management-induced variation in DOM chemistry. Further studies are needed to better constrain the effects of damming reservoirs on carbon cycling considering their booming all over the world.


Assuntos
Carbono , Ecossistema , Humanos , Hidrologia , Rios , Análise Espectral
10.
J Chromatogr A ; 1657: 462582, 2021 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-34614468

RESUMO

Biosynthesis is a research hot-spot in recent years, however, the purification of its final products is a tough work. Liquid stationary phase and large-scale separation ability of PZRCCC could easily avoid the commonly disadvantages occurred in traditional column chromatography. These characteristics makes PZRCCC particularly applicable for final products separation in biosynthesis. In this study, the glycosylation products of ellagic acid by one-pot glycosylation were successfully purified by PZRCCC to show the applicability of PZRCCC for preparative separation of biosynthesis products. An optimized ethyl acetate/n-buthanol/water (3:3:5, v/v/v) system was applied in this study, where 5 mM trifluoroacetic acid (TFA) as the retainer and 30 mM triethylamine (TEA) as the eluter were added. As a result, four ellagic acid glycosylation products, including 51 mg of ellagic acid-4, 3'-O-ß-D-diglucoside (EG-1), 24 mg of ellagic acid-4, 4'-O-ß-D-diglucoside (EG-2), 11 mg of ellagic acid-4-O-ß-D-glucosyl (1→2)-ß-D-glucoside (EG-3) and 64 mg of ellagic acid-4-O-ß-D-glucoside (EG-4) were simultaneously separated from 500 mg of glycosylation crude products, with the purity of 93.3%, 91.2%, 89.4% and 95.5%, respectively. Their structures were identified by spectroscopic analysis.


Assuntos
Distribuição Contracorrente , Extratos Vegetais , Glicosilação , Concentração de Íons de Hidrogênio
11.
J Chromatogr A ; 1612: 460666, 2020 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-31727356

RESUMO

The migration of bisphenols (BPs) can take place from plastic packaging materials into freshly cooked takeaway food, especially at high temperatures. In this study, cetyltrimethylammonium bromide-intercalated zinc oxide (ZnO@CTAB) was developed and used to extract the migration of BPs (bisphenol A and bisphenol AF) from disposable plastic materials to contained food simulates. Several experimental parameters that influence extraction efficiency were investigated. Under optimal conditions, a sensitive dispersive solid-phase extraction method based on ZnO@CTAB was proposed for the analysis of BPs coupled with ultra-high performance liquid chromatography and time-of-flight mass spectrometry. The method exhibited good linearity of calibration, high recovery (97.63-109.33%), low limits of detection 0.027-0.030 µg L-1, and acceptable precisions. The developed method was used to carry out a migration test from two disposable plastic bags and a disposable plastic container, using distilled water at 100 °C as a hot liquid food simulant. The migration concentrations of bisphenol AF was found to be 0.42 µg L-1 and 0.86 µg L-1 for the two types of disposable plastic bags, and the concentration of bisphenol A was 0.49 µg L-1 for disposable plastic container. The proposed method was also applied to investigate the migration of BPAF from the disposable plastic bags to different food simulants, revealing that the release of BPAF levels depended on the polarity of the liquid food components.


Assuntos
Compostos Benzidrílicos/análise , Embalagem de Alimentos , Espectrometria de Massas , Fenóis/análise , Plásticos/química , Adsorção , Compostos Benzidrílicos/isolamento & purificação , Cetrimônio/química , Cromatografia Líquida de Alta Pressão , Limite de Detecção , Fenóis/isolamento & purificação , Extração em Fase Sólida , Óxido de Zinco/química
12.
Exp Ther Med ; 16(2): 1165-1174, 2018 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-30116367

RESUMO

Bone marrow mesenchymal stem cells (BMSCs) are pluripotent cells, which have the capacity to differentiate into various types of mesenchymal cell phenotypes, including osteoblasts, chondroblasts, myoblasts and tendon fibroblasts (TFs). The molecular mechanism for tenogenic differentiation of BMSCs is still unknown. The present study investigated the effects of bone morphogenetic protein (BMP) 14 on BMSC differentiation in vitro. It was revealed that BMP14 significantly increased the expression of tendon markers (scleraxis and tenomodulin) at the mRNA and protein level, which led to the upregulation of sirtuin 1 (Sirt1) expression. The gain or loss of Sirt1 function may promote or inhibit tenogenic differentiation by deacetylating the peroxisome proliferator-activated receptor (PPAR)-γ. BMP14 also triggered the phosphorylation of c-Jun N-terminal kinase (JNK) and Smad1; overexpression of Sirt1 significantly increased the phosphorylation and knockdown of Sirt1 significantly decreased the phosphorylation. The inhibition of JNK and Smad significantly increased the acetylation of PPARγ and inhibited the expression of tenogenic differentiation markers. These results suggest that BMP14 may induce the tenogenic differentiation of BMSCs via the Sirt1-JNK/Smad1-PPARγ signaling pathway. The present study provided a cellular and molecular basis for the development of novel therapeutic strategies for tendon healing.

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