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1.
Int J Public Health ; 69: 1606913, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38572495

RESUMO

Objective: Identification of SCD risk is important in the general population from a public health perspective. The objective is to summarize and appraise the available prediction models for the risk of SCD among the general population. Methods: Data were obtained searching six electronic databases and reporting prediction models of SCD risk in the general population. Studies with duplicate cohorts and missing information were excluded from the meta-analysis. Results: Out of 8,407 studies identified, fifteen studies were included in the systematic review, while five studies were included in the meta-analysis. The Cox proportional hazards model was used in thirteen studies (96.67%). Study locations were limited to Europe and the United States. Our pooled meta-analyses included four predictors: diabetes mellitus (ES = 2.69, 95%CI: 1.93, 3.76), QRS duration (ES = 1.16, 95%CI: 1.06, 1.26), spatial QRS-T angle (ES = 1.46, 95%CI: 1.27, 1.69) and factional shortening (ES = 1.37, 95%CI: 1.15, 1.64). Conclusion: Risk prediction model may be useful as an adjunct for risk stratification strategies for SCD in the general population. Further studies among people except for white participants and more accessible factors are necessary to explore.


Assuntos
Morte Súbita Cardíaca , Humanos , Estados Unidos , Morte Súbita Cardíaca/epidemiologia , Morte Súbita Cardíaca/etiologia , Europa (Continente)/epidemiologia , Fatores de Risco , Medição de Risco
2.
Membranes (Basel) ; 13(7)2023 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-37504987

RESUMO

Ion-conducting ceramic membranes, such as mixed oxygen ionic and electronic conducting (MIEC) membranes and mixed proton-electron conducting (MPEC) membranes, have the potential for absolute selectivity for specific gases at high temperatures. By utilizing these membranes in membrane reactors, it is possible to combine reaction and separation processes into one unit, leading to a reduction in by-product formation and enabling the use of thermal effects to achieve efficient and sustainable chemical production. As a result, membrane reactors show great promise in the production of various chemicals and fuels. This paper provides an overview of recent developments in dense ceramic catalytic membrane reactors and their potential for chemical production. This review covers different types of membrane reactors and their principles, advantages, disadvantages, and key issues. The paper also discusses the configuration and design of catalytic membrane reactors. Finally, the paper offers insights into the challenges of scaling up membrane reactors from experimental stages to practical applications.

3.
Rev Sci Instrum ; 94(1): 013901, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36725584

RESUMO

Bimorph mirrors place stringent requirements on the welding technology of silicon substrates and piezoelectric ceramics to ensure their ultrahigh-vacuum compatibility. Conventional welding techniques usually require high temperature and pressure, which have a high impact on the welding substrate, while the use of organic adhesives for bonding does not guarantee their stability in ultrahigh vacuum. Here, the transient liquid phase bonding technology based on an Au-In metal system was studied to meet the requirement for ultrahigh-vacuum application. The microstructure, chemical composition, and related mechanical properties of the bonding at different welding conditions were investigated. Meanwhile, the piezo ceramics and the bond were baked at 150 °C to test the stability. The results show that a stable bonding was achieved between centimeter-scaled single crystal silicon and lead zirconate titanate ceramics at 200 °C temperature and 2.5 MPa pressure, and the piezo ceramics and the bond are not damaged by baking to 150 °C for 48 h.

4.
Opt Express ; 31(26): 43522-43534, 2023 Dec 18.
Artigo em Inglês | MEDLINE | ID: mdl-38178446

RESUMO

A two-dimensional (2D) mathematical model of quadratically distorted (QD) grating is established with the principles of Fraunhofer diffraction and Fourier optics. A discrete sampling method is applied for finding a numerical solution of the diffraction pattern of QD grating. An optimized working phase term, which determines the balanced energies and high efficiency of multi-plane images, can be obtained by the bisection algorithm. To confirm the analytical approach described above, the results have been compared with those obtained using a classical numerical model based on Fraunhofer diffraction theory and a fast Fourier transform (FFT) algorithm. The results show that our analytical approach allows the precise design of QD grating and improves the optical performance of simultaneous multi-plane imaging system. An optical setup based on our well-designed QD grating has been appended to the camera port of a commercial microscope, and some preliminary microscopy images have been successfully obtained. Further upgrade of our analytical model is in progress to improve the image quality and promote the applications.

5.
Bioorg Chem ; 129: 106221, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36341740

RESUMO

Glutathione (GSH) level has long been recognized as a valuable tumor biomarker. GSH-mediated activation and release systems have been extensively developed for cancer diagnosis and treatment, but mainly focused on disulfide-based conjugate. We reported here a new thiol-Michael addition based GSH response conjugate TC6, which consists of a unique tricyclic structure containing α, ß-unsaturated ketone responsive groups. The conjugate was easily synthesized and showed good selectivity to glutathione with certain stability. The camptothecin delivery experiment of TC6 showed improved anti-tumor ability in cells and tumor-bearing mice. TC6 could be used for the development of antibody or small molecule conjugated drugs.


Assuntos
Glutationa , Compostos de Sulfidrila , Camundongos , Animais , Compostos de Sulfidrila/farmacologia , Glutationa/química , Camptotecina/química , Cetonas , Dissulfetos
6.
Environ Res ; 214(Pt 3): 113858, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35952740

RESUMO

With the rapid development of industrial society, phenolic pollutants already identified in water are severe threats to human health. Traditional detection techniques like chromatography are poor in the ability of cost-effectiveness and on-site detection. In recent years, electrochemical enzymatic biosensors have attracted increasing attention for use in the recognition of phenolic compounds, which is considered an effective strategy for the product transfer of portable analytical devices. Although electrochemical enzymatic biosensors provide a fast, accurate on-site detection technique, the difficulties of enzyme deactivation, poor stability and low sensitivity remain to be solved. Thus, effective immobilization methods of enzymes and nanomaterials with excellent properties have been extensively researched to obtain a high-sensitivity and high-stability biosensing platform. Simultaneous detection of multiple phenols may become the focus of further research. In this review, we provide an overview of recent progress toward electrochemical enzymatic biosensors for the detection of phenolic compounds, including enzyme immobilization approaches and advanced nanomaterials, especially nanocomposites with attractive properties such as good conductivity, high specific surface area, and porous structure. We will comprehensively discuss the features and mechanisms of the main enzymes adopted in the construction of different phenolic biosensors, as well as traditional methods (e.g., adsorption, covalent bonding, entrapment, encapsulation, cross-linking) of enzyme immobilization. The most effective method is based on the properties of enzymes, supports and application objective because there is no one-size-fits-all method of enzymatic immobilization. The emphasis will be given to various advanced nanomaterials, including their special nanostructures, preparation methods and performance. Finally, the main challenges in future research on electrochemical phenolic biosensors will be discussed to provide further perspectives for practical applications in dynamic and on-site monitoring. We believe this review will deliver an important inspiration for the construction of novel and high-performance electrochemical biosensors from enzyme selection to nanomaterial design for the detection of various hazardous materials. We believe this review will deliver an important inspiration on the construction of novel and high-performance electrochemical biosensors from the enzyme selection to the nanomaterial design for detections of various hazardous materials.


Assuntos
Técnicas Biossensoriais , Nanoestruturas , Técnicas Biossensoriais/métodos , Enzimas Imobilizadas/química , Substâncias Perigosas , Humanos , Nanoestruturas/química , Fenóis , Água
7.
Food Chem Toxicol ; 162: 112908, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-35271983

RESUMO

Allura red (AR) is a member of azo dyes is commonly used as an additive in foods and soft drinks. However, due to the special harm of the azo structure to the human body, the dosage control of AR becomes particularly necessary. The present detection methods are time-consuming, expensive and complicated. In order to address the above issues, a core-shell nanocubes constructed sensor has been developed to determine the ultrawide detection range and selective recognition of AR with a long-term reusability. The core-shell architecture is composed of carbon material of 12.64 nm thickness covering 600 nm Mn3O4 nanocube. This nanocomposite combines the advantages of Mn3O4@C, possessing high electrocatalysis and chemical stability. As confirmed in using sports drinks as real samples, the as-prepared AR sensor exhibites excellent selectivity with an ultra-wide linear range from 0.1 to 1748.4 µM, and meanwhile, this sensor can also meet the requirements of remarkable anti-interference and reusability over 30 days.

8.
Opt Lett ; 47(6): 1331-1334, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290306

RESUMO

A lamellar multilayer grating in a conical diffraction mounting was proposed as a beam splitter for X-ray free-electron lasers. Theoretical calculations demonstrated that the distribution of diffraction efficiency can be adjusted by optimizing the groove depth or d-spacing. A Cr/C multilayer lamellar grating with a line density of approximately 2500 L/mm was fabricated. The performance of the element was measured in the Optics Beamline PM-1 (BESSY-II) at an energy of 1500 eV. A five-order diffraction pattern was recognized, and the diffraction efficiencies of the -/+first-order were approximately 12.6 and 4.4%, respectively. The asymmetric distribution of diffraction efficiency can be caused by the different sidewall angles of the grating groove.

9.
Appl Opt ; 60(31): 9925-9932, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34807182

RESUMO

The binary fused silica gratings (BFSGs) with high diffraction efficiency are presented for large astronomical ground-based telescopes. Calculations demonstrate that the BFSGs could obtain high diffraction efficiency in a wider wavelength range and angle of incident (AOI) range compared with volume phase holographic gratings. Several gratings with a size of 60mm×60mm have been fabricated by holographic lithography and reactive ion-beam etching technology. The measured peak diffraction efficiency reaches 94%, and results show that there are 130 nm wavelength bandwidth and 12° AOI bandwidth in which diffraction efficiency is higher than 70%. The stray light causes the diffraction efficiency to decrease by about 0.48%. All measurements have indicated good consistency with the simulation results.

10.
Medicine (Baltimore) ; 100(5): e23693, 2021 Feb 05.
Artigo em Inglês | MEDLINE | ID: mdl-33592828

RESUMO

ABSTRACT: This study aims to analyze the relationship between clinicopathological characteristics and survival in young patients (≤35 years old) with resected breast cancer.A total of 173 cases were included in this study. The clinicopathological factors potentially associated with prognosis were evaluated. Furthermore, we categorized patients into different groups to evaluate the prognosis according to hormone receptor status or important risk factors.Younger age (≤30 years) was an independent predictor for poor disease-free survival (DFS) and overall survival (OS). Besides, PR negative status, tumor grade, and advanced lymph nodes postsurgery were independent prognostic factors of DFS, while PR negative status and advanced lymph nodes postsurgery were independent prognostic factors of OS. For hormone receptor-positive patients, people with ER+ or PR+ and HER2-/+ showed poorer prognosis than the other 2 levels. Risk factor grouping based on the ER, PR, HER2, Ki-67 status, tumor grade, and lymph nodes postsurgery showed that patients in highest score group received the poorest prognosis. Grading system based on the hormone status or the risk factor grouping may offer a useful approach to assess which subgroups of young breast cancer present poorer prognosis.


Assuntos
Neoplasias da Mama/mortalidade , Neoplasias da Mama/patologia , Adulto , Fatores Etários , Biomarcadores Tumorais , Neoplasias da Mama/cirurgia , Intervalo Livre de Doença , Feminino , Humanos , Estimativa de Kaplan-Meier , Antígeno Ki-67/metabolismo , Metástase Linfática , Gradação de Tumores , Prognóstico , Receptores de Estrogênio/metabolismo , Receptores de Progesterona/metabolismo
11.
Sensors (Basel) ; 20(6)2020 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-32245186

RESUMO

Glutathione (GSH) is the main component of the mitochondrial thiol pool and plays key roles in the biological processes. Many evidences have suggested that cysteine and homocysteine also exist in mitochondria and are interrelated with GSH in biological systems. The fluctuation of the levels of mitochondrial thiols has been linked to many diseases and cells' dysfunction. Therefore, the monitoring of mitochondrial thiol status is of great significance for clinical studies. We report here a novel fluorescence resonance energy transfer based two-photon probe MT-1 for mitochondrial thiols detection. MT-1 was constructed by integrating the naphthalimide moiety (donor) and rhodamine B (accepter and targeting group) through a newly designed linker. MT-1 shows a fast response, high selectivity, and sensitivity to thiols, as well as a low limit of detection. The two-photon property of MT-1 allows the direct visualization of thiols in live cells and tissues by two-photon microscopy. MT-1 can serve as an effective tool to unravel the diverse biological functions of mitochondrial thiols in living systems.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Mitocôndrias/metabolismo , Compostos de Sulfidrila/metabolismo , Corantes Fluorescentes , Glutationa/química , Células HeLa , Humanos , Naftalimidas/química , Imagem Óptica , Rodaminas/química
12.
J Synchrotron Radiat ; 26(Pt 5): 1782-1789, 2019 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-31490170

RESUMO

A fabrication method comprising near-field holography (NFH) with an electron beam lithography (EBL)-written phase mask was developed to fabricate soft X-ray varied-line-spacing gratings (VLSGs). An EBL-written phase mask with an area of 52 mm × 30 mm and a central line density greater than 3000 lines mm-1 was used. The introduction of the EBL-written phase mask substantially simplified the NFH optics for pattern transfer. The characterization of the groove density distribution and diffraction efficiency of the fabricated VLSGs indicates that the EBL-NFH method is feasible and promising for achieving high-accuracy groove density distributions with corresponding image properties. Vertical stray light is suppressed in the soft X-ray spectral range.

13.
Carbohydr Polym ; 222: 114970, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31320043

RESUMO

Herein, we report novel macroporous membranes doped with micro-mesoporous ß-cyclodextrin polymers (ß-CDP), named ß-CDP membranes, for water decontamination by the flow-through process. These membranes combine excellent adsorption behavior of ß-CDP and the advantages of membranes filtration including low energy consumption and easy scale-up. Filtration adsorption results demonstrated that the optimal ß-CDP membrane removed > 99.9% of bisphenol A with ultrahigh water flux (3000 L m-2 h-1) or high concentration (50 mg L-1). The dynamic adsorption capacity of the membrane was close to the static maximum adsorption capacity of membrane, suggesting the effective accessibility of adsorption sites. The outstanding adsorption performance was attributed to the synergistic effect of the fast adsorption of ß-CDP, abundant ß-CDP nanoparticles and large contact area offered by spongy pores. Furthermore, not only single other organic micropollutants but also mixture was completely removed by the ß-CDP membranes. In addition, the membranes were easily regenerated by simple ethanol filtration.


Assuntos
Celulose/química , Ciclodextrinas/química , Filtração/métodos , Filtros Microporos , Purificação da Água/métodos , beta-Ciclodextrinas/química , Adsorção , Compostos Benzidrílicos/química , Fenóis/química , Poluentes Químicos da Água/análise
14.
Opt Lett ; 43(4): 811-814, 2018 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-29444000

RESUMO

Near-field holography (NFH) combined with electron beam lithography (EBL)-written phase masks is a promising method for the rapid realization of diffraction gratings with high resolution and high accuracy in line density distribution. We demonstrate a dynamic exposure method in which the grating substrate is shifted during pattern transfer. This reduces the effects of stitching errors, resulting in the decreased intensity of the optical stray light (i.e., Rowland ghosts). We demonstrate the intensity suppression of ghosts by 60%. This illustrates the potential for dynamic NFH to suppress undesirable periodic patterns from phase masks and alleviate the stitching errors induced by EBL.

15.
ACS Appl Mater Interfaces ; 9(35): 30024-30034, 2017 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-28796491

RESUMO

Flux and antifouling properties of mixed matrix membranes (MMMs) are yet to attain satisfactory status. The objective of this study is to find a method for mitigating the biofouling of poly(ether sulfone) (PES) ultrafiltration membranes via blending of thermoexfoliated vermiculite (VMT). Flow cytometry analysis shows that the behaviors of Bacillus subtilis 168 as a Gram-positive bacterium and Escherichia coli DH5 alpha as a Gram-negative bacterium were different. Hence, cell property is a suspected contributory factor in biofilm formation. Accordingly, considering the local predominant bacterial strains, a regionally customized membrane could scientifically be an expert solution for biofouling mitigation. Fabricated composite membranes have shown a higher flux compared to control PES membrane. Among all composite membranes, the PES-VMT0.10 had the highest flux of 476.4 L/(m2 h) (LMH) before fouling, and the highest flux of 210.7 LMH after three cycles of usage. In addition, the rejection rate of the PES-VMT0.15 The bovine serum albumin (BSA) sample was >77%, while that of the PES-VMT0.10 was >84%. The results of the static BSA adsorption test and the bacterial attachment test indicated that the membranes with macro-roughness on their surface showed better antibiofouling resistance. The antifouling properties of the modified membranes were also improved, because of their optimal wettability. On one hand, the hydrophilicity of membranes caused damaging both Gram-positive and Gram-negative bacteria and bacteriocidal effect. On the other hand, BSA adsorption and bacterial attachment on the membrane surface were affected by pore diameter.

16.
Adv Mater ; 29(18)2017 May.
Artigo em Inglês | MEDLINE | ID: mdl-28262998

RESUMO

The practical applications of perovskite hollow fibers (HFs) are limited by challenges in producing these easily, cheaply, and reliably. Here, a one-step thermal processing approach is reported for the efficient production of high performance perovskite HFs, with precise control over their cation stoichiometry. In contrast to traditional production methods, this approach directly uses earth-abundant raw chemicals in a single thermal process. This approach can control cation stoichiometry by avoiding interactions between the perovskites and polar solvents/nonsolvents, optimizes sintering, and results in high performance HFs. Furthermore, this method saves much time and energy (≈ 50%), therefore pollutant emissions are greatly reduced. One successful example is Ba0.5Sr0.5Co0.8Fe0.2O3-δ HFs, which are used in an oxygen-permeable membrane. This exhibits high oxygen permeation flux values that exceed desired commercial targets and compares favorably with previously reported oxygen-permeable membranes. Studies on other perovskites have produced similarly successful results. Overall, this approach could lead to energy efficient, solid-state devices for industrial application in energy and environmental fields.

17.
J Opt Soc Am A Opt Image Sci Vis ; 34(3): 308-313, 2017 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-28248373

RESUMO

The basic principle and method to generate structural color from the photoresist grating of the multilayer dielectric diffraction grating are introduced. Rigorous coupled-wave analysis is used for computation with the open software RCWA-1D. The relationships between the characteristics of the photoresist and the structural color are explained. This paper discusses the effect of light source characteristics on the duty cycle color resolution, indicating that TE polarization is better than TM polarization, and the FWHM should be sufficiently large with an optimized value for the incident angle.

18.
Analyst ; 141(13): 4018-23, 2016 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-27277339

RESUMO

Structure effects of distributed feedback (DFB) gratings on lasing action have been investigated for detecting explosive vapors. For the first time, we have established the optimized profiles of the DFB grating, and given the theoretical path to design its structure for amplified spontaneous emission (ASE) of organic polymer films based on Bragg conditions. A poly(p-phenylene ethynylene) (PPE) film can realize detection of dinitrotoluene (DNT) vapors in 2 min with a reduced excitation threshold of 26 mJ cm(-2) by using a simple and common 405 nm laser.

19.
Bioresour Technol ; 214: 144-149, 2016 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-27132221

RESUMO

The seaweed Ulva prolifera, distributed in inter-tidal zones worldwide, contains a large percentage of cellulosic materials. The technical feasibility of using U. prolifera residue (UPR) obtained after extraction of polysaccharides as a renewable energy resource was investigated. An environment-friendly and economical pretreatment process was conducted using hydrogen peroxide. The hydrogen peroxide pretreatment improved the efficiency of enzymatic hydrolysis. The resulting yield of reducing sugar reached a maximum of 0.42g/g UPR under the optimal pretreatment condition (hydrogen peroxide 0.2%, 50°C, pH 4.0, 12h). The rate of conversion of reducing sugar in the concentrated hydrolysates to bioethanol reached 31.4% by Saccharomyces cerevisiae fermentation, which corresponds to 61.7% of the theoretical maximum yield. Compared with other reported traditional processes on Ulva biomass, the reducing sugar and bioethanol yield are substantially higher. Thus, hydrogen peroxide pretreatment is an effective enhancement of the process of bioethanol production from the seaweed U. prolifera.


Assuntos
Biocombustíveis , Etanol/metabolismo , Peróxido de Hidrogênio/química , Alga Marinha/química , Ulva/química , Biomassa , Biotecnologia/métodos , Metabolismo dos Carboidratos , Carboidratos/química , Celulase/metabolismo , Fermentação , Hidrólise , Polissacarídeos , Saccharomyces cerevisiae/metabolismo , Alga Marinha/metabolismo , Ulva/metabolismo
20.
Adv Mater ; 28(18): 3511-5, 2016 05.
Artigo em Inglês | MEDLINE | ID: mdl-26970399

RESUMO

Unprecedented perovskite oxyfluoride membranes, a new generation of mixed ionic-electronic conducting (MIEC) membranes, feature extraordinary performance for low-temperature oxygen permeation, which transcend the performance of state-of-the-art MIEC membranes and fulfil commercial requirements. These results provide important progress for MIEC membranes and will potentially open the door to exploring high-performance MIEC compounds.

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