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1.
BMC Public Health ; 23(1): 2303, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37990228

RESUMO

BACKGROUND: The aggregation of lifestyle behaviours and their association with metabolic-associated fatty liver disease (MAFLD) remain unclear. We identified lifestyle patterns and investigated their association with the risk of developing MAFLD in a sample of Chinese adults who underwent annual physical examinations. METHODS: Annual physical examination data of Chinese adults from January 2016 to December 2020 were used in this study. We created a scoring system for lifestyle items combining a statistical method (multivariate analysis of variance) and clinical expertise (Delphi method). Subsequently, principal component analysis and two-step cluster analysis were implemented to derive the lifestyle patterns of men and women. Binary logistic regression analysis was used to explore the prevalence risk of MAFLD among lifestyle patterns stratified by sex. RESULTS: A total of 196,515 subjects were included in the analysis. Based on the defined lifestyle scoring system, nine and four lifestyle patterns were identified for men and women, respectively, which included "healthy or unhealthy" patterns and mixed patterns containing a combination of healthy and risky lifestyle behaviours. This study showed that subjects with an unhealthy or mixed pattern had a significantly higher risk of developing MAFLD than subjects with a relatively healthy pattern, especially among men. CONCLUSIONS: Clusters of unfavourable behaviours are more prominent in men than in women. Lifestyle patterns, as important factors influencing the development of MAFLD, show significant sex differences in the risk of MAFLD. There is a strong need for future research to develop targeted MAFLD interventions based on the identified behavioural clusters by sex stratification.


Assuntos
Estilo de Vida , Hepatopatia Gordurosa não Alcoólica , Adulto , Feminino , Humanos , Masculino , Estudos Transversais , Análise por Conglomerados , Análise Multivariada , China/epidemiologia
2.
Biomed Opt Express ; 14(9): 4862-4874, 2023 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-37791252

RESUMO

A multimodal nonlinear optical imaging platform based on a single femtosecond oscillator is built for simultaneous TPEF and SF-CARS imaging. TPEF microscopy and SF-CARS microscopy is utilized for mapping the distribution of the lignin component and the polysaccharide component, respectively. Visualization of vessel structure is realized. And the relative distribution of lignin and polysaccharide of vessel structure is mapped. Two pumpkin stem tissue areas with different degrees of lignification are observed with simultaneous TPEF and SF-CARS imaging, and two types of cell walls are identified. The different distribution patterns of lignin and polysaccharide in these two types of cell walls, induced by different degrees of lignification, are analyzed in detail.

3.
World J Hepatol ; 15(8): 985-1000, 2023 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-37701916

RESUMO

BACKGROUND: Recently, a group of hepatologists proposed to rename non-alcoholic fatty liver disease (NAFLD) as metabolic associated fatty liver disease (MAFLD) with modified diagnostic criteria. It is important to note, however, that there are some differences between the diagnostic criteria used for NAFLD and MAFLD. Since the research on MAFLD is just beginning, however, evidence on its incidence and prevalence in the general population and in specific subpopulations remains limited. AIM: To assess epidemiology of fatty liver in new definition and compare MAFLD with NAFLD. Exploring risk factors of MAFLD individuals. METHODS: This was a retrospective, cross-sectional study. A total of 85242 adults were selected from the Chinese health management database in 2017-2022. The data of general information, laboratory indicators, lifestyle management and psychological status were obtained. MAFLD was diagnosed as ultrasound diagnosis of fatty liver and at least one between these three conditions: Overweight/obesity, type 2 diabetes mellitus (T2DM) or metabolic dysregulation. Metabolic factors were not considered in NAFLD diagnosis standard. The clinical characteristics of MAFLD and NAFLD were analysed using descriptive statistics. Continuous variables normally distributed were expressed as means ± SD. Categorical variables were expressed as frequencies and proportions. Binary logistic regression was used to determine risk factors of the MAFLD. RESULTS: The prevalence of MAFLD and NAFLD was 40.5% and 31.0%, respectively. The MAFLD or NAFLD population is more likely to be older (M: 47.19 ± 10.82 vs 43.43 ± 11.96; N: 47.72 ± 11.17 vs 43.71 ± 11.66), male (M: 77.21% vs 44.43%; N: 67.90% vs 53.12%) and high body mass index (M: 26.79 ± 2.69 vs 22.44 ± 2.48; N: 26.29 ± 2.84 vs 23.29 ± 3.12) than the non-MAFLD or non-MAFLD population. In multivariate analysis, general information (e.g., ≥ 2 metabolic abnormalities OR = 3.38, (95%CI: 2.99-3.81), P < 0.001; diastolic blood pressure OR = 1.01, (95%CI: 1.00-1.01), P = 0.002), laboratory results [e.g.,total bilirubin (TBIL) OR = 0.98, (95%CI: 0.98-0.99), P < 0.001; serum uric acid(SUA) OR = 1.01, (95%CI: 1.01-1.01), P < 0.001], and lifestyle factors [e.g., drink beverage OR = 0.32, (95%CI: 0.17-0.63), P = 0.001] were influence factors for MAFLD. Our study results offer new insight into potential risk factors associated with fatty liver disease, including SUA, TBIL and creatinine, all of which are related to chronic renal disease (CKD). CONCLUSION: MAFLD is more prevalent than NAFLD, with two-fifths of individuals meeting the diagnosis criteria. MAFLD and NAFLD populations have different clinical characteristics. CKD may be related with MAFLD.

4.
Opt Express ; 31(2): 1878-1887, 2023 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-36785213

RESUMO

A high temporal waveform fidelity stimulated Brillouin scattering phase conjugate mirror (SBS-PCM) with high energy efficiency, based on a novel medium, Novec-7500, is proposed and practically achieved in this study. A theoretical analysis reveals that the temporal-domain waveform distortion is caused by the inherent pulse duration compression effect of the SBS, and this undesirable phenomenon can be significantly suppressed by decreasing the compression coefficient (CC afterwards), which is defined as the gain coefficient divided by the phonon lifetime, which coefficient and is identified as the key parameter for high waveform-fidelity in SBS-PCM. The feasibility of this approach was demonstrated experimentally, in which a reflected pulse with waveform symmetry equals to the pump and an average pulse duration of 0.974 τp (τp is the duration of pump) with an energy efficiency of over 90% was achieved using Novec-7500.

5.
J Phys Chem Lett ; 12(48): 11710-11716, 2021 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-34846910

RESUMO

Semiconductor nanocrystals (NCs) are emerging luminescent materials with superior optical properties. However, the light-conversion application of NCs is restricted by reabsorption-induced fluorescent quenching. Here, a NC-NC Förster resonance energy transfer (FRET) system is developed by employing large CsPbBr3 NCs as donors and CdSe/CdS NCs as acceptors. The FRET systems using toluene and octadecene as solvents show decreases of 10% and 14%, respectively, in the integrated photoluminescence (PL) intensity, far below the reabsorption loss observed in concentrated CdSe/CdS NCs (>30%) at the same color purity. Notably, we demonstrate by transient absorption measurements that the styrene-mediated FRET system involves a Dexter energy transfer process, which enables the harvesting of triplet excitons and leads to an additional PL enhancement at system level by a maximum of 40% instead of fluorescence quenching. The remarkably improved light-conversion efficiency and antiquenching property make the proposed NC-NC system superior in light down-conversion applications.

6.
J Phys Chem Lett ; 12(26): 6165-6173, 2021 Jul 08.
Artigo em Inglês | MEDLINE | ID: mdl-34184904

RESUMO

Physical vapor deposition has emerged as a promising strategy for efficient and stable all-inorganic perovskite light-emitting devices (PeLEDs). However, the thermally evaporated PeLEDs still suffer from unsatisfactory optoelectrical performance because of the massive nonradiative defects. Herein, we demonstrate an efficient bilateral interfacial defect-passivation strategy toward high-performance PeLEDs with a thermally deposited CsPbBr3 emissive layer (EML). Specifically, the nonradiative defects from the bulk as well as the EML/charge transport layer (CTL) interface are significantly suppressed by implementing the 3-amino-1-propanol (3AP)-modified PEDOT:PSS and introducing ammonium salts, respectively. Simultaneously, both the 3AP induced less-conductive Cs4PbBr6 and ammonium salts can balance the charge injection into the EML effectively. As a result, we achieved efficient PeLEDs based on thermally evaporated CsPbBr3 with a luminance of 15745 cd/m2, current efficiency of 32 cd/A, external quantum efficiency of 8.86%, and lifetime of 3.74 h. The strategy proposed here may shed light on the development of highly efficient thermally evaporated PeLEDs.

7.
Opt Express ; 26(26): 34474-34483, 2018 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-30650870

RESUMO

We demonstrate a multi-color background-free coherent anti-Stokes Raman scattering (CARS) imaging system, using a robust, all-fiber, low-cost, multi-wavelength time-lens source. The time-lens source generates picosecond pulse trains at three different wavelengths. The first is 1064.3 nm, the second is tunable between 1052 nm and 1055 nm, and the third is tunable between 1040 nm and 1050 nm. When the time-lens source is synchronized with a mode-locked Ti:Sa laser, two of the three wavelengths are used to detect different Raman frequencies for two-color on-resonance imaging, whereas the third wavelength is used to obtain the off-resonance image for nonresonant background subtraction. Mixed poly(methyl methacrylate) (PMMA) and polystyrene (PS) beads are used to demonstrate two-color background-free CARS imaging. The synchronized multi-wavelength time-lens source enables pixel-to-pixel wavelength-switching. We demonstrate simultaneous two-color CARS imaging of CH2 and CH3 stretching vibration modes with real-time background subtraction in ex vivo mouse tissue.

8.
Anal Chem ; 87(18): 9436-42, 2015 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-26291845

RESUMO

Highly lignified vascular plant cell walls represent the majority of cellulosic biomass. Complete release of the biomass to deliver renewable energy by physical, chemical, and biological pretreatments is challenging due to the "protection" provided by polymerized lignin, and as such, additional tools to monitor lignin deposition and removal during plant growth and biomass deconstruction would be of great value. We developed a hyperspectral stimulated Raman scattering microscope with 9 cm(-1) spectral resolution and submicrometer spatial resolution. Using this platform, we mapped the aromatic ring of lignin, aldehyde, and alcohol groups in lignified plant cell walls. By multivariate curve resolution of the hyperspectral images, we uncovered a spatially distinct distribution of aldehyde and alcohol groups in the thickened secondary cell wall. These results collectively contribute to a deeper understanding of lignin chemical composition in the plant cell wall.


Assuntos
Arabidopsis/citologia , Parede Celular/metabolismo , Lignina/metabolismo , Microscopia/métodos , Análise Espectral Raman , Vibração , Álcoois/metabolismo , Aldeídos/metabolismo , Arabidopsis/genética , Lignina/química , Mutação , Oxirredução
9.
J Xray Sci Technol ; 22(1): 105-11, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24463389

RESUMO

We experimentally study the harmonics from a Xe-He gas mixture using tight-focusing femtosecond laser pulses. The spectrum in the mixed gases exhibits an extended cutoff region from the harmonic H21 to H27. The potential explanation is that the harmonics photons from Xe contribute the electrons of He atoms to transmit into the excited-state. Therefore, the harmonics are emitted from He atoms easily. Furthermore, we show that there are the suppressed harmonics H15 and H17 in the mixed gases. The underlying mechanism is the destructive interference between harmonics generated from different atoms. Our results indicate that HHG from Xe-He gas mixture is an efficient method of obtaining the coherent soft X-ray source.


Assuntos
Gases/química , Lasers , Análise Espectral/instrumentação , Raios X , Acústica , Desenho de Equipamento , Gases/análise , Análise Espectral/métodos
10.
J Chromatogr B Analyt Technol Biomed Life Sci ; 879(22): 2064-72, 2011 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-21704571

RESUMO

To support toxicokinetic assessments, a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed and validated for the quantification of BMS-790052 in rat, dog, monkey, rabbit and mouse K(2)EDTA plasma. The drug was isolated from buffered samples using ISOLUTE C8 96-well solid phase extraction (SPE) plates. Chromatographic separation was achieved on a Waters Atlantis dC18 analytical column (2.1 mm × 50 mm, 5 µm) with detection accomplished using an API 4000 tandem mass spectrometer in positive ion electrospray and multiple reaction monitoring (MRM) mode. The standard curves, which ranged from 5.00 to 2000 ng/mL for BMS-790052, were fitted to a 1/x(2) weighted linear regression model. The intra-assay precision (%CV) and inter-assay precision (%CV) were within 8.5%, and the assay accuracy (%Dev) was within ±7.1 for rat, dog, monkey, rabbit and mouse K(2)EDTA plasma. This accurate, precise, and selective SPE/LC-MS/MS method has been successfully applied to analyze several thousands of non-clinical study samples.


Assuntos
Antivirais/sangue , Cromatografia Líquida/métodos , Imidazóis/sangue , Espectrometria de Massas em Tandem/métodos , Proteínas não Estruturais Virais/antagonistas & inibidores , Animais , Antivirais/administração & dosagem , Antivirais/farmacocinética , Carbamatos , Cães , Estabilidade de Medicamentos , Drogas em Investigação , Feminino , Haplorrinos , Imidazóis/administração & dosagem , Imidazóis/farmacocinética , Modelos Lineares , Masculino , Camundongos , Pirrolidinas , Coelhos , Ratos , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Valina/análogos & derivados
11.
Opt Express ; 18(20): 21062-73, 2010 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-20941002

RESUMO

A three-state model for calculating the cross section of laser-induced dipole-quadrupole collisional energy transfer in Sr-Ca system is presented. The motion equations for the probability amplitudes of the three intermediate states are obtained. The expression of the cross section is derived. Various factors including field intensity, relative speed, system temperature which influence the collisional cross section are discussed to illustrate the features of the dipole-quadrupole laser-induced collisional energy transfer (LICET)process. Calculating results show that the peak of the LICET profiles moves to the red, the tuning range of the profiles obviously becomes narrower with the laser field intensity increasing and a cross section of 1.25 × 10(-13)cm(2) at a laser intensity of 8.29 × 10(9)W/cm(2) is obtained. Our results indicate that dipole-quadrupole LICET process can be the effective way to transfer energy selectively from a storage state of arbitrary parity to a target state of arbitrary parity.

12.
Guang Pu Xue Yu Guang Pu Fen Xi ; 30(2): 462-5, 2010 Feb.
Artigo em Chinês | MEDLINE | ID: mdl-20384146

RESUMO

The effects of the stability of dye laser on the signal to noise ratio in degenerate four-wave mixing (DFWM) were first investigated in iodine vapor using forward geometries. Frequency-doubled outputs from a multi-mode Nd : YAG laser pumped dye laser with laser dye PM580 dissolved in ethanol was used. With the help of forward compensated beam-split technique and imaging detecting system, the saturation intensity of DFWM spectrum in the iodine vapor at 5 554.013 nm was first measured to be 290 microJ under the condition of atmospheric pressure and room temperature. The features of the dye laser such as wavelength ranges, beam quality and energy conversion efficiency decreased gradually with increasing pumping service use, pulse number and intensity. Additionally, with the comparison of the stable and unstable dye laser output, it was found that the instability of dye laser output had greatly influenced the DFWM signal and decreased the signal to background noise ratio. Shot to shot jitter and the broadening in the output frequency leads to an effective broadening of the recorded spectrum and loss of the DFWM signal to noise ratio under the same pumping intensity at different time. The study is of importance to the detection of trace atom, molecule and radical in combustion diagnosis.

13.
Opt Express ; 16(13): 9804-10, 2008 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-18575549

RESUMO

Broad band solid state dye lasers based on LDS 698 doped in modified polymethyl methacrylate (MPMMA) with laser wavelength about 650 nm were demonstrated. It was demonstrated that the fluorescence spectra of LDS 698 in solid host MPMMA displays an obvious blue shift about 50 nm comparing with that in ethanol solution. The dye concentration has great effect on the laser's performance including laser slope efficiency and lifetime. The lifetime increased dramatically with the increase of the LDS 698 concentration. With pump repetition rate of 10 Hz and intensity of 0.1 J/cm(2), the maximum lifetime 300,000 shots corresponding normalized photostability 102 GJ/mol was obtained with LDS 698 at 1.5 x 10(-4)mol/L.


Assuntos
Corantes Fluorescentes/química , Lasers de Estado Sólido , Modelos Teóricos , Polimetil Metacrilato/química , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
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