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1.
Comput Biol Med ; 177: 108631, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38824787

RESUMO

The incident light reflected from the cornea is rich in information about the human surroundings, and these reflected rays are imaged by the camera, which can be used for research on human consciousness and gaze analysis, and produce certain help in the fields of psychology, human computer interaction and disease diagnosis. However, limited by the low corneal reflection ability, when a high-definition camera captures corneal reflecting rays, a large amount of color and texture interference from the iris can seriously contaminate the corneal reflection images, resulting in low usability and ubiquity of corneal reflection images. In this paper, we propose a corneal reflection image extraction method with multiple eye images as input. We align the iris regions of multiple eye images with the help of iris localization method, and by comparing multiple iris regions, we obtain the complementary iris regions, so that the iris interference in the corneal reflection region can be stripped completely. A large number of experiments have demonstrated that our work can effectively mitigate iris interference and effectively improve the quality of corneal reflection images.


Assuntos
Córnea , Processamento de Imagem Assistida por Computador , Humanos , Córnea/diagnóstico por imagem , Processamento de Imagem Assistida por Computador/métodos , Iris/diagnóstico por imagem , Algoritmos
2.
Opt Express ; 31(9): 13763-13797, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37157257

RESUMO

Conventional (CP) and Fourier (FP) ptychography have emerged as versatile quantitative phase imaging techniques. While the main application cases for each technique are different, namely lens-less short wavelength imaging for CP and lens-based visible light imaging for FP, both methods share a common algorithmic ground. CP and FP have in part independently evolved to include experimentally robust forward models and inversion techniques. This separation has resulted in a plethora of algorithmic extensions, some of which have not crossed the boundary from one modality to the other. Here, we present an open source, cross-platform software, called PtyLab, enabling both CP and FP data analysis in a unified framework. With this framework, we aim to facilitate and accelerate cross-pollination between the two techniques. Moreover, the availability in Matlab, Python, and Julia will set a low barrier to enter each field.

3.
BMC Geriatr ; 22(1): 942, 2022 12 07.
Artigo em Inglês | MEDLINE | ID: mdl-36476421

RESUMO

BACKGROUND: Previous Chinese studies focused on the prevalence and influential factors of hypertension; however, little is known about their self-care literacy and quality of life among the Bai older adults with hypertension. The purpose of this research was to explore the associations among health-promoting lifestyle, self-care agency, and health-related quality of life in Bai ethnic older patients with hypertension, as well as the related factors of hypertension self-care abilities. METHODS: A total of 472 Bai ethnic hypertension older adults aged 60 and above were enrolled in this study voluntarily from 5 rural communities of the Bai ethnic group. The Exercise of Self-Care Agency Scale (ESCAS) was employed to assess the Self-care ability of hypertension for the subjects, the Health-promoting lifestyle profile II(HPLP-II) was utilized to evaluate the health behavior, and MOS 36-Item Short Form Health Survey (SF-36) was chosen to assess the HRQOL for the studying population. All descriptive analyses, including demographic characteristics, socio-economic status, and clinical characteristics were stratified by Bai hypertensive elderly. Pearson correlation analysis model was used to examine the associations among health-promoting lifestyle, self-care agency, and health-related quality of life in Bai ethnic elderly with hypertension. RESULTS: The HPLP-II, ESCA, and of HRQOL levels of the subjects were low, and the mean HPLP and ESCA scores had no significant statistical variance among different age groups. Significant statistical differences were found in Bai elderly subjects in the domain of PF and PH as well as the overall score in SF-36(all P< 0.01), 60-64 year group had the highest score of the above three domains in SF-36 than other age groups. The SF-36 scores were positively associated with HPLP and ESCA levels. CONCLUSION: The HPLP-II, ESCA, and of HRQOL levels of the Bai subjects were poor in the Bai ethnic hypertensive elderly. The HRQOL scores of subjects were positively connected with HPLP-II and ESCA abilities. More attention should be paid to lifestyle, healthy behaviors, and self-care abilities improvements to enhance the better HRQOL of Bai minority older adults with hypertension.


Assuntos
Hipertensão , Autocuidado , Humanos , Idoso , Qualidade de Vida , China/epidemiologia , Exercício Físico , Hipertensão/epidemiologia , Hipertensão/terapia
4.
Artigo em Inglês | MEDLINE | ID: mdl-35845584

RESUMO

Shixiao powder comes from the Formularies of the Bureau of People's Welfare Pharmacies in the Song Dynasty and consists of two herbs, Puhuang (PH) and Wulingzhi (WLZ). PH-WLZ is a commonly used drug pair for the treatment of coronary heart disease (CHD), and its clinical effect is remarkable. However, our understanding of the mechanism of treatment of CHD is still unclear. In this study, the method of network pharmacology was used to explore the mechanism of PH-WLZ in the treatment of CHD. A total of 56 active ingredients were identified from PH-WLZ, of which 93 targets of 41 active ingredients overlapped with those of CHD. By performing Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis, we obtained the main pathways associated with CHD and those associated with the mechanism of PH-WLZ in the treatment of CHD. By constructing the protein-protein interaction (PPI) network of common targets, 10 hub genes were identified. Based on the number of hub genes contained in the enrichment analysis, we obtained the key pathways of PH-WLZ in the treatment of CHD. The key KEGG pathway in the treatment of CHD by PH-WLZ is mainly enriched in atherosclerosis, inflammation, immunity, oxidative stress, and infection-related pathways. Moreover, the results of molecular docking showed that the active ingredients of PH-WLZ had a good affinity with the hub genes. The results indicate that the mechanism of PH-WLZ in the treatment of CHD may be related to regulation of lipid metabolism, regulation of immune and inflammatory responses, regulation of downstream genes of fluid shear stress, antiaging and oxidative stress, and virus inhibition.

5.
Nat Commun ; 13(1): 3231, 2022 Jun 09.
Artigo em Inglês | MEDLINE | ID: mdl-35680925

RESUMO

Force-reversible C-N bonds, resulting from the click chemistry reaction between triazolinedione (TAD) and indole derivatives, offer exciting opportunities for molecular-level engineering to design materials that respond to mechanical loads. Here, we displayed that TAD-indole adducts, acting as crosslink points in dry-state covalently crosslinked polymers, enable materials to display reversible stress-responsiveness in real time already at ambient temperature. Whereas the exergonic TAD-indole reaction results in the formation of bench-stable adducts, they were shown to dissociate at ambient temperature when embedded in a polymer network and subjected to a stretching force to recover the original products. Moreover, the nascent TAD moiety can spontaneously and immediately be recombined after dissociation with an indole reaction partners at ambient temperature, thus allowing for the adjustment of the polymer segment conformation and the maintenance of the network integrity by force-reversible behaviors. Overall, our strategy represents a general method to create toughened covalently crosslinked polymer materials with simultaneous enhancement of mechanical strength and ductility, which is quite challenging to achieve by conventional chemical methods.

6.
Opt Lett ; 47(8): 1949-1952, 2022 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-35427308

RESUMO

Reflection ptychography is a lensfree microscopy technique particularly promising in regions of the electromagnetic spectrum where imaging optics are inefficient or not available. This is the case in tabletop extreme ultraviolet microscopy and grazing incidence small angle x ray scattering experiments. Combining such experimental configurations with ptychography requires accurate knowledge of the relative tilt between the sample and the detector in non-coplanar scattering geometries. Here, we describe an algorithm for tilt estimation in reflection ptychography. The method is verified experimentally, enabling sample tilt determination within a fraction of a degree. Furthermore, the angle-estimation uncertainty and reconstruction quality are studied for both smooth and highly structured beams.

7.
Opt Lett ; 46(6): 1337-1340, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33720181

RESUMO

Ptychography is a robust computational imaging technique that can reconstruct complex light fields beyond conventional hardware limits. However, for many wide-field computational imaging techniques, including ptychography, depth sectioning remains a challenge. Here we demonstrate a high-resolution three-dimensional (3D) computational imaging approach, which combines ptychography with spectral-domain imaging, inspired by optical coherence tomography (OCT). This results in a flexible imaging system with the main advantages of OCT, such as depth-sectioning without sample rotation, decoupling of transverse and axial resolution, and a high axial resolution only determined by the source bandwidth. The interferometric reference needed in OCT is replaced by computational methods, simplifying hardware requirements. As ptychography is capable of deconvolving the illumination contributions in the observed signal, speckle-free images are obtained. We demonstrate the capabilities of ptychographic optical coherence tomography (POCT) by imaging an axially discrete lithographic structure and an axially continuous mouse brain sample.


Assuntos
Processamento de Imagem Assistida por Computador/métodos , Tomografia de Coerência Óptica/métodos , Animais , Encéfalo/diagnóstico por imagem , Camundongos
8.
Opt Express ; 28(5): 6443-6451, 2020 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-32225892

RESUMO

To reduce the threshold and achieve unidirectional lasing emission in a whispering gallery mode microcavity, we propose and demonstrate a GaN-based eccentric microring with an inner hole located off the center. Compared to microdisk with the same outer diameter, the eccentric microring structure exhibits a remarkable reduction of lasing threshold by up to 53%. The introduction of the hole disturbs and eventually suppresses the field distribution of the higher order modes. Laser emission with high unidirectionality with a far-field divergence angle of about 40° has been achieved, meanwhile the Q factor of the whispering gallery modesis remains high as 6388. Finite-difference time-domain numerical simulation is carried out to prove that the far-field profile of the eccentric microring structure can be controlled by the position and the size of the hole. The properties of the whispering gallery mode microcavities are improved greatly through a simple structure and process, which has an important guiding significance to the research and development of the microcavity lasers.

9.
Opt Lett ; 45(7): 2030-2033, 2020 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-32236060

RESUMO

An autofocusing algorithm for ptychography is proposed. The method optimizes a sharpness metric that would be observed in a differential interference microscope and is valid for both amplitude and phase modulating specimens. We experimentally demonstrate that the algorithm, based on the extended ptychographic iterative engine (ePIE), calibrates the sample-detector distance with an accuracy within the depth of field of the ptychographic microscope. We show that the method can be used to determine slice separation in multislice ptychography, provided there are isolated regions on each slice of the specimen that do not axially overlap.

10.
Opt Express ; 28(4): 5022-5034, 2020 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-32121731

RESUMO

We report on an approach for quantitative characterization of laser beam quality, wavefronts, and lens aberrations using ptychography with a near-infrared supercontinuum laser. Ptychography is shown to offer a powerful alternative for both beam propagation ratio M2 and wavefront measurements compared with existing techniques. In addition, ptychography is used to recover the transmission function of a microlens array for aberration analysis. The results demonstrate ptychography's flexibility in wavefront metrology and optical shop testing.

11.
Macromol Rapid Commun ; 41(5): e1900606, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32003531

RESUMO

Supramolecular chemistry has provided versatile and affordable solutions for the design of tough, flexible polymers. However, application of supramolecular chemistry has been limited to the production of rigid, high-performance polymers due to weak segment mobility. This paper describes a new method of toughening rigid high-performance polymers using the synergistic effect between dual Cu2+ -coordination bonds as a crosslink. These dual Cu2+ -coordination cross-linked high-performance polymers are a class of rigid polymers with an outstanding combination of strength and toughness. The distinct lifetimes and binding strengths of the dual Cu2+ -coordination bonds in a rigid polymer network elicit different dynamic behaviors to improve its energy dissipation and mechanical properties. Moreover, the reformation and removal of Cu2+ -coordination bonds by pyrophosphoric acid endows these cross-linked high-performance polymers with recyclability.


Assuntos
Cobre/química , Polímeros/química , Difosfatos/química , Ligação de Hidrogênio , Teste de Materiais , Reciclagem , Temperatura
12.
BMC Geriatr ; 19(1): 326, 2019 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-31766992

RESUMO

BACKGROUND: The purpose of this research was to assess the health-related quality of life (HRQOL) and functional abilities of Yi and Han elderly who resided in Yi Autonomous prefecture or Counties in Yunnan Province, as well as to compare their differences in HRQOL, functional abilities and other factors. METHODS: A total of 1636 older subjects, which included 863 Han and 773 Yi, were recruited from 10 Yi Autonomous regions. Their HRQOL and functional capabilities were assessed by the MOS 36-Item Short Form Health Survey (SF-36), activities of daily living (ADL), and instrumental activities of daily living (IADL) scales. RESULTS: The Han elderly performed better in every domain of SF-36 than the Yi elderly. Both of the two ethnic groups could perform their ADL independently but the Yi elderly showed greater dependency in IADL abilities. The HRQOL was positively associated with their ADL, IADL, and education levels. Moreover, age, health insurance status, and living arrangement were negatively correlated with HRQOL. CONCLUSION: The HRQOL and IADL capabilities of the Han elderly were higher than that of the Yi counterparts in the Yi Autonomous regions. The HRQOL of both the two ethnic groups was positively connected with ADL, IADL abilities as well as education levels, whereas it was negatively correlated with age and health insurance. The elderly-care policy on the Yi autonomous areas should focus more on the HRQOL, ADL improvement, education background, age needs, and health insurance, etc.


Assuntos
Atividades Cotidianas/psicologia , Envelhecimento/etnologia , Envelhecimento/psicologia , Etnicidade/psicologia , Qualidade de Vida/psicologia , Idoso , Idoso de 80 Anos ou mais , China/etnologia , Estudos Transversais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
13.
Analyst ; 144(4): 1260-1264, 2019 Feb 21.
Artigo em Inglês | MEDLINE | ID: mdl-30543216

RESUMO

A novel fluorescent probe for Pd2+ based on the BODIPY fluorophore exploiting the PET (Photoinduced Electron Transfer) mechanism was designed and successfully synthesized. The fluorescent probe 1 was prepared by introducing m-bisimidazolylbenzene which was connected by phenyl acetylene to the BODIPY dye at the meso position. It exhibited a rapid response and high sensitivity and selectivity toward Pd2+. Probe 1 presented a rapid quenched fluorescence response in aqueous buffer media (pH 5.5) and the detection limit estimated from the titration results was 2.9 × 10-7 M. Meanwhile, other common metal ions did not interfere with the recognition process. The DFT calculation proved that coordination of bisimidazole ligands with Pd2+ effectively decreases the LUMO energy of m-bisimidazolylbenzene which was located between the HOMO and LUMO energies of the BODIPY dye leading to fluorescence quenching via the d-PET mechanism.

14.
Macromol Rapid Commun ; 39(10): e1800031, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29656407

RESUMO

Crosslinked high-performance polymers have many industrial applications but are difficult to recycle. Visual detection of the physical properties of the crosslinked high-performance polymers is useful, but is difficult to achieve. The crosslinked high-performance polymers (SPIN) are constructed by using cation-π interactions. The cation-π interaction between the polymer side chains can be easily installed and removed by aqueous treatments at high or low pH, respectively, which endow the crosslinked polymer with a recyclable behavior. Additionally, the tensile strength and glass transition temperature of the SPIN films could be visually detected by taking advantage of the transparency decreasing effect of cation to an adjacent indole unit.


Assuntos
Materiais Biocompatíveis/química , Vidro/química , Polímeros/química , Cátions/química , Resistência à Tração , Temperatura de Transição
15.
Chem Commun (Camb) ; 54(23): 2906-2909, 2018 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-29497731

RESUMO

Metal coordination crosslinking between stiff N-polyindole chains was constructed, and the crosslinked films exhibited high tensile strength, high heat resistance and excellent polar solvent resistance. The noncovalent crosslinking can be further removed via external pyrophosphate, which endows the crosslinked polymer with a recyclable behavior. The tensile strength and glass transition temperature of the polymers can be nondestructively detected by taking advantage of the fluorescence quenching effect of metal coordination to the adjacent bipyridine structure.

16.
BMC Geriatr ; 17(1): 74, 2017 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-28330442

RESUMO

BACKGROUND: The health-related quality of life (HRQoL) of the elderly population of Yi ethnic minority, which is the seventh largest nationality in China, has been rarely reported. This study was designed to explore the HRQoL of the elderly Yi ethnicity and association between their HRQOL and functional abilities. METHODS: A total of 291 Yi ethnic residents were randomly recruited from 12 rural counties in Yunnan province and divided into different age groups. Local residents in Yunnan province and the elderly from Hangzhou were enrolled as controls. The MOS 36-Item Short Form Health Survey (SF-36), activities of daily living (ADL), instrumental activities of daily living (IADL) scales were utilized to evaluate the HRQoL and functional ability. One-way ANOVA was used to statistically compare the ADL and IADL among different age groups. The influential variables on HRQOL were analyzed by multiple linear regression analysis. Pearson correlation analysis was used to analyze the association among HRQoL, ADL and IADL. RESULTS: The HRQoL of the elderly Yi minority was significantly lower than those of local residents in Yunnan province and the elderly counterparts in Hangzhou. The IADL ability of the elderly Yi minority was low, whereas they could perform most items of ADL. ADL, IADL, and education level were positively associated with HRQoL, whereas age, chronic diseases, and the frequency of medication use were negatively correlated with HRQoL. CONCLUSION: The HRQoL and functional capacity of the elderly Yi ethnic minority were lower compared with their counterparts in Yunnan province and Hangzhou. The low level of IADL indicated that the elderly Yi participants had a high risk of cognitive impairment. Much attention should be diverted to influential factors of the HRQoL.


Assuntos
Atividades Cotidianas/psicologia , Etnicidade/psicologia , Nível de Saúde , Qualidade de Vida/psicologia , População Rural , Inquéritos e Questionários , Idoso , Idoso de 80 Anos ou mais , China/etnologia , Doença Crônica , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/etnologia , Transtornos Cognitivos/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade
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