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1.
Opt Express ; 31(23): 37843-37860, 2023 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-38017905

RESUMO

In this study we present an investigation of electrically tunable progressive lenses utilizing liquid crystals (LC). We introduce a polarized progressive LC lens capable of dynamically adjusting its focal length, functioning as either a positive or negative lens. Our findings reveal that the spatial distribution of lens power within the progressive LC lens, ranging from +4D to -3D, far surpassing the range of -0.87D to +0.87D which one may expect within the parabolic wavefront approximation. For a lens with a 30 mm aperture a total tunable range is 7.6 D (from +5.6D to -2D) which is 4.75 times larger than the traditional parabolic prediction∼1.6D (from +0.8D to -0.8D). This study not only challenges conventional limitations set by optical phase differences in gradient-index LC lenses (the power law) but also ushers in a new possibility for ophthalmic applications. The profound insights and outcomes presented in this paper redefine the landscape of LC lenses, paving the way for transformative advancements in optics and beyond.

2.
Polymers (Basel) ; 15(18)2023 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-37765617

RESUMO

Given the issues of soil cracking, poor water retention during drought, and erosion damage caused by rainfall, we conducted an in-depth study on the water retention properties, cracking resistance, and scouring resistance of biogel-amended clay using evaporation cracking and scouring tests. The hydrophysical properties and cohesive aggregation mechanism of biogel-amended clay were explored, and the results showed that the incorporation of biogel improved the water retention, cracking resistance, and scour resistance of the clay samples. With an increase in the biogel content, the biogel mucous membrane inside the samples improved the cohesion between soil particles, reduced the generation and development of cracks, and improved the cracking resistance. There was no significant cracking of the samples after the biogel content reached 0.3%, which changed the migration of water in the sample, prevented water evaporation, and improved the water retention of the clay samples. Biofilm can change the migration of water in the sample, prevent some evaporation, and reduce the evaporation rate. To a certain extent, it can enhance the water retention capacity of the sample. Enhanced biofilm content significantly reduced scouring in the process of rainfall and runoff erosion of the sample, and biofilm content of 0.2% significantly reduced the surface of the specimen damaged by erosion. The hydrophysical properties of the composite-adhesive-amended clay samples were significantly improved compared with those of the single-bioadhesive-amended clay samples.

3.
Opt Express ; 30(15): 28250, 2022 Jul 18.
Artigo em Inglês | MEDLINE | ID: mdl-36236977

RESUMO

We have an addendum for our previous paper [Opt. Express30, 22768 (2022)10.1364/OE.461378] cite previous prior works from the N. A. Riza lab that earlier reported a high speed lens based on digital polarization switching in cascade with birefringent fixed and tunable optical beamforming elements and its application for volumetric displays.

4.
Opt Express ; 30(13): 22768-22778, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-36224967

RESUMO

The major challenges of augmented reality (AR) systems and virtual reality (VR) systems are varifocal images for vergence-accommodation conflict (VAC) and vision corrections. In this paper, we design a liquid crystal (LC) lens set consisting of three LC lenses for varifocal images and vision corrections in AR and VR. Four operating modes of such a LC lens set present three electrically tunable lens powers: 0, -0.79 diopters, -2 diopters, and -3.06 diopters by means of manipulation of polarization of incident light using electrically tunable half-wave-plates. The response time is fast(< 50 ms). We also demonstrate AR and VR systems by adopting the LC lens set to exhibit functions of varifocal images and vision corrections which enable to solve VAC as well as vision problem in AR and VR.

5.
Biochem Pharmacol ; 201: 115099, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35617999

RESUMO

Periodontal diseases are prevalent worldwide. Lipoteichoic acid (LTA), a major component of gram-positive bacteria, may play a key role in periodontally inflammatory diseases. Carbon monoxide (CO) is a critical messenger in many biological processes. It can elicit various biological properties, especially anti-inflammatory effects. As the straight administration of CO remains difficult, CO-releasing molecules (CO-RMs) are emerging as promising alternatives. To explore the pharmacological actions and signaling pathways of CO battling LTA-induced periodontal inflammation, this study investigated the cytoprotective effects of CORM-2 against the adhesion of THP-1 monocytes to human gingival fibroblasts (HGFs) and the underlying molecular mechanism. After exposing HGFs to LTA with or without CORM-2 pretreatment, monocyte adhesion was determined. VCAM-1 and ICAM-1 expression in HGFs was measured by real-time PCR. To identify the signaling pathways of CO involved in the cytoprotective effects of CORM-2, HGFs underwent pharmacological or genetical interventions before LTA incubation. The expression and/or activity of possible regulatory molecules were determined. The release of pro-inflammatory cytokines, including IL-1ß, IL-6, and TNF-α, were measured using ELISA. The results showed that LTA increased cytokine production and upregulated VCAM-1 and ICAM-1 expression in HGFs, promoting monocyte adhesion. These events were dependent on TLR2/MyD88/TRAF6- and PI3K/Akt/NADPH oxidase/ROS-regulated NF-κB activation. CORM-2 inhibited LTA-induced inflammatory cascades in HGFs, in which CO seemed to be the hitman. To conclude, CO released from CORM-2 can prevent the LTA-stimulated HGFs from increasing VCAM-1 and ICAM-1 expression and promoting monocyte adhesion by inhibiting TLR2/MyD88/TRAF6 association and PI3K/Akt/NADPH oxidase/ROS signaling, both converge on the canonical NF-κB activation.


Assuntos
NF-kappa B , Compostos Organometálicos , Espécies Reativas de Oxigênio , Fator 6 Associado a Receptor de TNF , Receptor 2 Toll-Like , Molécula 1 de Adesão de Célula Vascular , Fibroblastos , Humanos , Molécula 1 de Adesão Intercelular/genética , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos , Fator 88 de Diferenciação Mieloide/metabolismo , NADPH Oxidases/metabolismo , NF-kappa B/metabolismo , Compostos Organometálicos/farmacologia , Fosfatidilinositol 3-Quinases/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais , Fator 6 Associado a Receptor de TNF/metabolismo , Ácidos Teicoicos , Receptor 2 Toll-Like/genética , Receptor 2 Toll-Like/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Molécula 1 de Adesão de Célula Vascular/metabolismo
6.
Molecules ; 26(3)2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-33573267

RESUMO

To improve the properties of mesoporous carbon (MC), used as a catalyst support within electrodes, MC fibers (MCFs) were successfully synthesized by combining organic-organic self-assembly and electrospinning deposition and optimizing heat treatment conditions. The pore structure was controlled by varying the experimental conditions. Among MCFs, MCF-A, which was made in the most acidic condition, resulted in the largest pore diameter (4-5 nm), and the porous structure and carbonization degree were further optimized by adjusting heat treatment conditions. Then, since the fiber structure is expected to have an advantage when MCFs are applied to devices, MCF-A layers were prepared by spray printing. For the resistance to compression, MCF-A layers showed higher resistance (5.5% change in thickness) than the bulk MC layer (12.8% change in thickness). The through-plane resistance was lower when the fiber structure remained more within the thin layer, for example, +8 mΩ for 450 rpm milled MCF-A and +12 mΩ for 800 rpm milled MCF-A against the gas diffusion layer (GDL) 25BC carbon paper without a carbon layer coating. The additional advantages of MCF-A compared with bulk MC demonstrate that MCF-A has the potential to be used as a catalyst support within electrodes in energy devices.


Assuntos
Fibra de Carbono/química , Carbono/química , Nanoestruturas/química , Catálise , Eletrodos , Humanos , Porosidade , Propriedades de Superfície
7.
Poult Sci ; 100(3): 100869, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33516481

RESUMO

Fatty liver diseases, common metabolic diseases in chickens, can lead to a decrease in egg production and sudden death of chickens. To solve problems caused by the diseases, reliable chicken models of fatty liver disease are required. To generate chicken models of fatty liver, 7-week-old ISA female chickens were fed with a control diet (17% protein, 5.3% fat, and 1,300 mg/kg choline), a low protein and high fat diet (LPHF, 13% protein, 9.1% fat, and 1,300 mg/kg choline), a high cholesterol with low choline diet (CLC, 17% protein, 7.6% fat with additional 2% cholesterol, and 800 mg/kg choline), a low protein, high fat, high cholesterol, and low choline diet (LPHFCLC, 13% protein, 12.6% fat with additional 2% cholesterol, and 800 mg/kg choline) for 4 wk. Our data showed that the CLC and LPHFCLC diets induced hyperlipidemia. Histological examination and the content of hepatic lipids indicated that the CLC and LPHFCLC diets induced hepatic steatosis. Plasma dipeptidyl peptidase 4, a biomarker of fatty liver diseases in laying hens, increased in chickens fed with the CLC or LPHFCLC diets. Hepatic ballooning and immune infiltration were observed in these livers accompanied by elevated interleukin 1 beta and lipopolysaccharide induced tumor necrosis factor mRNAs suggesting that the CLC and LPHFCLC diets also caused steatohepatitis in these livers. These diets also induced hepatic steatosis in Plymouth Rock chickens. Thus, the CLC and LPHFCLC diets can be used to generate models for fatty liver diseases in different strains of chickens. In ISA chickens fed with the CLC diet, peroxisome proliferator-activated receptor γ, sterol regulatory element binding transcription factor 1, and fatty acid synthase mRNAs increased in the livers, suggesting that lipogenesis was enhanced by the CLC treatment. Our data show that treatment with CLC or LPHFCLC for 4 wk induces fatty liver disease in chickens. These diets can be utilized to rapidly generate chicken models for fatty liver research.


Assuntos
Galinhas , Colesterol , Colina , Dieta , Fígado Gorduroso , Hiperlipidemias , Animais , Colesterol/metabolismo , Colina/metabolismo , Dieta/veterinária , Modelos Animais de Doenças , Fígado Gorduroso/fisiopatologia , Fígado Gorduroso/veterinária , Feminino , Hiperlipidemias/veterinária , Fígado/patologia , Doenças das Aves Domésticas/fisiopatologia
8.
Dalton Trans ; 47(43): 15565-15573, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30346021

RESUMO

A series of five-membered ring aluminum complexes bearing thiol-Schiff base ligands were synthesized, and their application in the ring-opening polymerization of ε-caprolactone (CL) was investigated. The complexes exhibited dramatically higher catalytic activity than the six-membered ring S2AlMe2 complex (approximately 4- to 10-fold higher) and the five-membered ring L5-PhAlMe2 complex (approximately 7- to 19-fold higher). Moreover, a shorter induction period was observed when the five-membered ring aluminum complexes bearing thiol-Schiff base ligands were used compared with the other types of aluminum complexes bearing Schiff base ligands. The electron-withdrawing groups enhanced the catalytic activity of the Al complexes compared with the electron donating groups. The thiol-Schiff base ligand and the five-membered ring aluminum catalysis had a synergistic effect that was stronger than the combination of their individual effects.

9.
J Biomed Opt ; 22(4): 45007, 2017 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-28421226

RESUMO

Oral cancer is a serious and growing problem in many developing and developed countries. To improve the cancer screening procedure, we developed a portable light-emitting-diode (LED)-induced autofluorescence (LIAF) imager that contains two wavelength LED excitation light sources and multiple filters to capture ex vivo oral tissue autofluorescence images. Compared with conventional means of oral cancer diagnosis, the LIAF imager is a handier, faster, and more highly reliable solution. The compact design with a tiny probe allows clinicians to easily observe autofluorescence images of hidden areas located in concave deep oral cavities. The ex vivo trials conducted in Taiwan present the design and prototype of the portable LIAF imager used for analyzing 31 patients with 221 measurement points. Using the normalized factor of normal tissues under the excitation source with 365 nm of the central wavelength and without the bandpass filter, the results revealed that the sensitivity was larger than 84%, the specificity was not smaller than over 76%, the accuracy was about 80%, and the area under curve of the receiver operating characteristic (ROC) was achieved at about 87%, respectively. The fact shows the LIAF spectroscopy has the possibilities of ex vivo diagnosis and noninvasive examinations for oral cancer.


Assuntos
Carcinoma de Células Escamosas/diagnóstico por imagem , Fluorescência , Luz , Neoplasias Bucais/diagnóstico por imagem , Espectrometria de Fluorescência/métodos , Adulto , Idoso , Detecção Precoce de Câncer , Desenho de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/metabolismo , Curva ROC , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Taiwan
10.
Appl Opt ; 54(28): E136-45, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26479643

RESUMO

Transparent display is one of the main technologies in next-generation displays, especially for augmented reality applications. An aperture structure is attached on each display pixel to partition them into transparent and black regions. However, diffraction blurs caused by the aperture structure typically degrade the transparent image when the light from a background object passes through finite aperture window. In this paper, the diffraction effect of an active-matrix organic light-emitting diode display (AMOLED) is studied. Several aperture structures have been proposed and implemented. Based on theoretical analysis and simulation, the appropriate aperture structure will effectively reduce the blur. The analysis data are also consistent with the experimental results. Compared with the various transparent aperture structure on AMOLED, diffraction width (zero energy position of diffraction pattern) of the optimize aperture structure can be reduced 63% and 31% in the x and y directions in CASE 3. Associated with a lenticular lens on the aperture structure, the improvement could reach to 77% and 54% of diffraction width in the x and y directions. Modulation transfer function and practical images are provided to evaluate the improvement of image blurs.

11.
Appl Opt ; 53(29): H27-34, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25322428

RESUMO

Diabetes is a familiar disease in modern society. In the early stage of diabetes, symptoms are unobvious, but they usually induce diabetic autonomic neuropathy or, worse, cardiovascular autonomic neuropathy. Pupillometers are effective instruments for observing human pupils. This article presents a novel wearable pupillometer design, without external light artifacts, and an embedded algorithm with blinking elimination, which investigates autonomic neuropathy through recording pupil dynamics triggered by an external sensitive invisible light source. The pupillometer is experimented on 36 healthy subjects and 10 diabetic patients under four different colors (white, red, green, and blue) as well as two different light intensities: 50 and 500 mcd. Ten parameters derived from pupil diameter, pupil response time, and pupil response speed will be evaluated for the healthy subjects and diabetic patients. The results show that three in four parameters related to pupil diameters, one in four related to light intensities, and one in two related to pupil response speed could have significant differences (p<0.05) between healthy subjects and diabetic patients. These parameters obtain over 85% sensitivity, 83% specificity, and 88% accuracy. The pupillometer is proven reliable, effective, portable, and inexpensive for diagnosing diabetes in an early stage.


Assuntos
Retinopatia Diabética/diagnóstico , Óculos , Monitorização Ambulatorial/instrumentação , Oftalmoscópios , Estimulação Luminosa/instrumentação , Distúrbios Pupilares/diagnóstico , Reflexo Pupilar , Adulto , Retinopatia Diabética/complicações , Retinopatia Diabética/fisiopatologia , Diagnóstico por Computador/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Exame Neurológico/instrumentação , Distúrbios Pupilares/etiologia , Distúrbios Pupilares/fisiopatologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Appl Opt ; 53(29): H76-84, 2014 Oct 10.
Artigo em Inglês | MEDLINE | ID: mdl-25322435

RESUMO

Different levels of visual fatigue in the human eye depend on different color-formation methods and image quality. This paper uses the high-frequency component of the spectral power of accommodative microfluctuations as a major objective indicator for analyzing the effects of visual fatigue based on various displays, such as color-formation displays and 3D displays. Also, a questionnaire is used as a subjective indicator. The results are that 3D videos cause greater visual fatigue than 2D videos (p<0.001), the shutter-type 3D display causes visual fatigue more than the polarized type (p=0.012), the display of the time-sharing method causes greater visual fatigue than the spatial-formation method (p=0.008), and there is no significance between various light source modules of displays (p=0.162). In general, people with normal color discrimination have more visual fatigue than those with good color discrimination (p<0.001). Therefore, this paper uses the high-frequency component of accommodative microfluctuations to evaluate the physiological stress or strain by overexerting the visual system, and can compare the level of visual fatigue between various displays.


Assuntos
Acomodação Ocular , Astenopia/fisiopatologia , Apresentação de Dados , Lasers , Cristais Líquidos , Estimulação Luminosa/instrumentação , Percepção Visual , Adulto , Cor , Desenho de Equipamento , Análise de Falha de Equipamento , Feminino , Humanos , Imageamento Tridimensional/instrumentação , Imageamento Tridimensional/métodos , Masculino , Estimulação Luminosa/métodos , Análise e Desempenho de Tarefas
13.
BMC Complement Altern Med ; 13: 237, 2013 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-24070160

RESUMO

BACKGROUND: Alpinia oxyphylla is a common remedy in traditional Chinese medicine. Yakuchinone A is a major constituent of A. oxyphylla and exhibits anti-inflammatory, antitumor, antibacterial, and gastric protective activities. METHODS: Antioxidant and antitumor characteristics of yakuchinone A in skin cancer cells as well as novel mechanisms for the inhibition of adipocyte differentiation, cestocidal activities against Hymenolepis nana adults, and nematocidal activities against Anisakis simplex larvae are investigated. RESULTS: Yakuchinone A presents the ability of the removal of DPPH·and ABTS+ free radicals and inhibition of lipid peroxidation. Yakuchinone A suppresses intracellular lipid accumulation during adipocyte differentiation in 3 T3-L1 cells and the expressions of leptin and peroxisome proliferator-activated receptor γ (PPARγ). Yakuchinone A induces apoptosis and inhibits cell proliferation in skin cancer cells. The inhibition of cell growth by yakuchinone A is more significant for non-melanoma skin cancer (NMSC) cells than for melanoma (A375 and B16) and noncancerous (HaCaT and BNLCL2) cells. Treatment BCC cells with yakuchinone A shows down-regulation of Bcl-2, up-regulation of Bax, and an increase in cleavage poly (ADP-ribose) polymerase (PARP). This suggests that yakuchinone A induces BCC cells apoptosis through the Bcl-2-mediated signaling pathway. The anthelmintic activities of yakuchinone A for A. simplex are better than for H. nana. CONCLUSIONS: In this work, yakuchinone A exhibits antioxidative properties, anti-adipocyte differentiation, antitumor activity, and anthelmintic activities against A. simplex and H. nana.


Assuntos
Alpinia/química , Anti-Helmínticos/farmacologia , Antioxidantes/farmacologia , Diferenciação Celular/efeitos dos fármacos , Guaiacol/análogos & derivados , Adipócitos/citologia , Adipócitos/efeitos dos fármacos , Adipogenia/efeitos dos fármacos , Animais , Anisakis/efeitos dos fármacos , Anti-Helmínticos/química , Antioxidantes/química , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Guaiacol/química , Guaiacol/farmacologia , Humanos , Hymenolepis nana/efeitos dos fármacos , Larva/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Transdução de Sinais/efeitos dos fármacos
14.
Opt Express ; 20(18): 20059-70, 2012 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-23037058

RESUMO

In recent years, displays and lighting require color temperature (CT) conversion function because observers have different preferences. This paper proposes effective methods to determine the optimal converting point of CT conversion for display and lighting application. For display application, the concepts of center of gravity and isotemperature line are applied to determine the optimal converting point. The maximal enhancement of luminance between the optimal and average is 18%. For lighting application, this paper proposes two methods to determine the optimal converting point in the CT quadrangle which complies with ANSI C78. 377. The enhancement of luminance in two CT modes (5700K and 6500K) are 14.2% and 23.6%, respectively.


Assuntos
Algoritmos , Colorimetria/instrumentação , Colorimetria/normas , Iluminação/instrumentação , Iluminação/normas , Cor , Padrões de Referência , Temperatura , Estados Unidos
15.
J Opt Soc Am A Opt Image Sci Vis ; 26(10): 2163-71, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19798393

RESUMO

The gamut boundary description (GBD) of multiprimary color displays (MPD) is important for color gamut mapping. Dependent primary color (DPC) is the color stimulus of a controllable color channel represented by an additive mixture of positive amounts of other primary colors. We propose a method to obtain the GBD of a MPD with one DPC. Further, the ideal color volume in CIE xyY and CIE L*a*b* color space with complete-controlling white channel is about 218.8% and 144% compared with the one of digital light processing with incomplete-controlling white channel. The white channel with complete control will not only increase brightness, but also expand color volume.

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