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1.
Sensors (Basel) ; 23(22)2023 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-38005536

RESUMO

An automotive 2.1 µm CMOS image sensor has been developed with a full-depth deep trench isolation and an advanced readout circuit technology. To achieve a high dynamic range, we employ a sub-pixel structure featuring a high conversion gain of a large photodiode and a lateral overflow of a small photodiode connected to an in-pixel storage capacitor. With the sensitivity ratio of 10, the expanded dynamic range could reach 120 dB at 85 °C by realizing a low random noise of 0.83 e- and a high overflow capacity of 210 ke-. An over 25 dB signal-to-noise ratio is achieved during HDR image synthesis by increasing the full-well capacity of the small photodiode up to 10,000 e- and suppressing the floating diffusion leakage current at 105 °C.

2.
Sensors (Basel) ; 23(9)2023 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-37177412

RESUMO

Mercury bromide (Hg2Br2) has been used to develop acousto-optic tunable filters (AOTFs) because it has several advantages, including a high refractive index, a broad optical bandwidth, and a relatively high figure of merit. Therefore, the measurement of its birefringence is a highly important factor for ensuring AOTF quality. However, for single crystals, it is difficult (at the millimeter scale) to quantify the birefringence using an ellipsometer, as this equipment is only designed to conduct measurements on thin films. In this study, a simple birefringence measurement system for Hg2Br2 was developed based on Brewster's angle at the millimeter scale. The planar distributions of the Hg2Br2 crystal along the (100), (010), and (001) planes were used in the experiments. The developed measurement system can measure the reflected light intensity of the Hg2Br2 crystal depending on the incidence angles (rotations at 0.01125° steps) and can calculate the ordinary and extraordinary refractive indices and birefringence. The calculated birefringence of the Hg2Br2 crystal was 0.8548; this value exhibits an error of 0.64% compared with a value of 0.86 reported in the literature. The developed measurement system demonstrates the ability to be used to evaluate the quality of birefringent single crystals.

3.
Sensors (Basel) ; 22(24)2022 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-36560195

RESUMO

Environmental pressures, such as temperature and light intensity, food, and genetic factors, can cause chicken eggs to develop abnormalities. The common types of internal egg abnormalities include bloody and damaged egg yolk. Spectrometers have been recently used in real-time abnormal egg detection research. However, there are very few studies on the optimization of measurement systems. This study aimed to establish optimum parameters for detecting of internal egg abnormalities (bloody and damaged-yolk eggs) using visible and near-infrared (Vis/NIR) spectrometry (192-1110 nm range) and multivariate data analysis. The detection performance using various system parameters, such as the types of light sources, the configuration of the light, and sensor positions, was investigated. With the help of collected data, a partial least-squares discriminant analysis (PLS-DA) model was developed to classify normal and abnormal eggs. The highest classification accuracy for the various system parameters was 98.7%. Three band selection methods, such as weighted regression coefficient (WRC), sequential feature selection (SFS), and successive projection algorithm (SPA) were used for further model optimization, to reduce the spectral bands from 1028 to less than 7. In conclusion the results indicate that the types of light sources and the configuration design of the sensor and illumination affect the detection accuracy for abnormal eggs.


Assuntos
Galinhas , Espectroscopia de Luz Próxima ao Infravermelho , Animais , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Ovos/análise , Gema de Ovo , Análise Discriminante , Análise dos Mínimos Quadrados
4.
Molecules ; 25(8)2020 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-32316426

RESUMO

Ginkgo biloba leaf (GBL) is known as a potential source of bioactive flavonoids, such as quercetin, arresting the neuronal soluble N-ethylmaleimide-sensitive factor attachment protein receptor (SNARE)-zippering. Here, the GBL flavonoids were isolated in two different manners and then examined for their bioactivity, physicochemical stability, and biocompatibility. The majority of flavonoids in the non-hydrolyzed and acidolyzed isolates, termed non-hydrolyzed isolate (NI) and acidolyzed isolate (AI) hereafter, were rich in flavonol glycosides and aglycones, respectively. Glycosidic/aglyconic quercetin and kaempferol were abundant in both NI and AI, whereas a little of apigenin, luteolin, and isorhamnetin were found in AI. NI was more thermostable in all pH ranges than quercetin, kaempferol, and AI. NI and AI both inhibited neurotransmitter release from differentiated neuronal PC-12 cells. NI and AI showed 1/2-1/3 lower EC50/CC50 values than quercetin and kaempferol. The NI and AI exhibited no toxicity assessed by the tests on chorioallantoic membranes of hen's eggs, removing toxicological concerns of irritation potential. Moreover, GBL isolates, particularly AI, showed antioxidant and anti-inflammatory activities in the use below the CC50 levels. Taken together, these results suggest that GBL isolates that are rich in antioxidant flavonoids are effective anti-neuroexocytotic agents with high stability and low toxicity.


Assuntos
Exocitose/efeitos dos fármacos , Flavonoides/química , Flavonoides/farmacologia , Ginkgo biloba/química , Neurônios/efeitos dos fármacos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Animais , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Antioxidantes/química , Antioxidantes/farmacologia , Sobrevivência Celular , Cromatografia Líquida de Alta Pressão , Flavonoides/isolamento & purificação , Concentração de Íons de Hidrogênio , Camundongos , Extratos Vegetais/isolamento & purificação , Relação Estrutura-Atividade , Transmissão Sináptica/efeitos dos fármacos , Espectrometria de Massas em Tandem
5.
Sensors (Basel) ; 20(1)2020 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-31947811

RESUMO

The grading of ginseng (Panax ginseng) including the evaluation of internal quality attributes is essential in the ginseng industry for quality control. Assessment for inner whitening, a major internal disorder, must be conducted when identifying high quality ginseng. Conventional methods for detecting inner whitening in ginseng root samples use manual inspection, which is time-consuming and inaccurate. This study develops an internal quality measurement technique using near-infrared transmittance spectral imaging to evaluate inner whitening in ginseng samples. Principle component analysis (PCA) was used on ginseng hypercube data to evaluate the developed technique. The transmittance spectra and spectral images of ginseng samples exhibiting inner whitening showed weak intensity characteristics compared to normal ginseng in the region of 900-1050 nm and 1150-1400 nm respectively, owing to the presence of whitish internal tissues that have higher optical density. On the basis of the multivariate analysis method, even a simple waveband ratio image has the great potential to quickly detect inner whitening in ginseng samples, since these ratio images show a significant difference between whitened and non-whitened regions. Therefore, it is possible to develop an efficient and rapid spectral imaging system for the real-time detection of inner whitening in ginseng using minimal spectral wavebands. This novel strategy for the rapid, cost-effective, non-destructive detection of ginseng's inner quality can be a key component for the automation of ginseng grading.


Assuntos
Técnicas Biossensoriais , Imagem Molecular , Panax/química , Doenças das Plantas/genética , Humanos , Análise Multivariada , Panax/genética , Panax/ultraestrutura , Análise de Componente Principal , Controle de Qualidade , República da Coreia , Espectroscopia de Luz Próxima ao Infravermelho
6.
PLoS One ; 13(4): e0195253, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29708973

RESUMO

The potential adulteration of foodstuffs has led to increasing concern regarding food safety and security, in particular for powdered food products where cheap ground materials or hazardous chemicals can be added to increase the quantity of powder or to obtain the desired aesthetic quality. Due to the resulting potential health threat to consumers, the development of a fast, label-free, and non-invasive technique for the detection of adulteration over a wide range of food products is necessary. We therefore report the development of a rapid Raman hyperspectral imaging technique for the detection of food adulteration and for authenticity analysis. The Raman hyperspectral imaging system comprises of a custom designed laser illumination system, sensing module, and a software interface. Laser illumination system generates a 785 nm laser line of high power, and the Gaussian like intensity distribution of laser beam is shaped by incorporating an engineered diffuser. The sensing module utilize Rayleigh filters, imaging spectrometer, and detector for collection of the Raman scattering signals along the laser line. A custom-built software to acquire Raman hyperspectral images which also facilitate the real time visualization of Raman chemical images of scanned samples. The developed system was employed for the simultaneous detection of Sudan dye and Congo red dye adulteration in paprika powder, and benzoyl peroxide and alloxan monohydrate adulteration in wheat flour at six different concentrations (w/w) from 0.05 to 1%. The collected Raman imaging data of the adulterated samples were analyzed to visualize and detect the adulterant concentrations by generating a binary image for each individual adulterant material. The results obtained based on the Raman chemical images of adulterants showed a strong correlation (R>0.98) between added and pixel based calculated concentration of adulterant materials. This developed Raman imaging system thus, can be considered as a powerful analytical technique for the quality and authenticity analysis of food products.


Assuntos
Contaminação de Alimentos/análise , Pós/química , Análise Espectral Raman/instrumentação , Peróxido de Benzoíla/análise , Calibragem , Capsicum/química , Vermelho Congo/análise , Desenho de Equipamento , Farinha/análise , Lasers , Análise Espectral Raman/métodos , Triticum/química , Interface Usuário-Computador
7.
Food Chem ; 220: 505-509, 2017 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-27855931

RESUMO

Qualitative properties of roasting defect coffee beans and their classification methods were studied using hyperspectral imaging (HSI). The roasting defect beans were divided into 5 groups: medium roasting (Cont), under developed (RD-1), over roasting (RD-2), interior under developed (RD-3), and interior scorching (RD-4). The following qualitative properties were assayed: browning index (BI), moisture content (MC), chlorogenic acid (CA), trigonelline (TG), and caffeine (CF) content. Their HSI spectra (1000-1700nm) were also analysed to develop the classification methods of roasting defect beans. RD-2 showed the highest BI and the lowest MC, CA, and TG content. The accuracy of classification model of partial least-squares discriminant was 86.2%. The most powerful wavelength to classify the defective beans was approximately 1420nm (related to OH bond). The HSI reflectance values at 1420nm showed similar tendency with MC, enabling the use of this technology to classify the roasting defect beans.


Assuntos
Coffea/química , Coffea/classificação , Culinária/métodos , Processamento de Imagem Assistida por Computador/métodos , Alcaloides/análise , Cafeína/análise , Ácido Clorogênico/análise , Culinária/instrumentação , Análise Discriminante , Temperatura Alta , Análise dos Mínimos Quadrados
8.
PLoS One ; 6(11): e27566, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22132113

RESUMO

Parkinson's disease (PD) is caused by the selective loss of dopaminergic neurons in the substantia nigra (SN) and the depletion of striatal dopamine (DA). Acupuncture, as an alternative therapy for PD, has beneficial effects in both PD patients and PD animal models, although the underlying mechanisms therein remain uncertain. The present study investigated whether acupuncture treatment affected dopamine neurotransmission in a PD mouse model using 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine (MPTP). We found that acupuncture treatment at acupoint GB34 improved motor function with accompanying dopaminergic neuron protection against MPTP but did not restore striatal dopamine depletion. Instead, acupuncture treatment increased dopamine release that in turn, may lead to the enhancement of dopamine availability in the synaptic cleft. Moreover, acupuncture treatment mitigated MPTP-induced abnormal postsynaptic changes, suggesting that acupuncture treatment may increase postsynaptic dopamine neurotransmission and facilitate the normalization of basal ganglia activity. These results suggest that the acupuncture-induced enhancement of synaptic dopamine availability may play a critical role in motor function improvement against MPTP.


Assuntos
Terapia por Acupuntura , Dopamina/metabolismo , Atividade Motora/fisiologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/terapia , Sinapses/metabolismo , 1-Metil-4-Fenil-1,2,3,6-Tetra-Hidropiridina , Pontos de Acupuntura , Animais , Comportamento Animal , Modelos Animais de Doenças , Fosfoproteína 32 Regulada por cAMP e Dopamina/metabolismo , Neurônios Dopaminérgicos/metabolismo , Neurônios Dopaminérgicos/patologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Modelos Biológicos , Neostriado/patologia , Neostriado/fisiopatologia , Degeneração Neural/complicações , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Fosforilação , Proteínas Proto-Oncogênicas c-fos/metabolismo , Sinapses/patologia , Fatores de Tempo
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