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1.
Appl Opt ; 63(8): 2056-2064, 2024 Mar 10.
Artículo en Inglés | MEDLINE | ID: mdl-38568647

RESUMEN

The optical distortion of the lithographic projection lens can reduce imaging quality and cause overlay errors in lithography, thus preventing the miniaturization of printed patterns. In this paper, we propose a technique to measure the optical distortion of a lithographic projection lens by sensing the wavefront aberrations of the lens. A multichannel dual-grating lateral shearing interferometer is used to measure the wavefront aberrations at several field points in the pupil plane simultaneously. Then, the distortion at these field points is derived according to the proportional relationship between the Z 2 and Z 3 Zernike terms (the tilt terms) and the image position shifts. Without the need for additional devices, our approach can simultaneously retrieve both the wavefront aberrations and the image distortion information. Consequently, it improves not only measurement speed and accuracy but also enables accounting for displacement stage positioning error. Experiments were conducted on a lithographic projection lens with a numerical aperture of 0.57 to verify the feasibility of the proposed method.

3.
Sci Rep ; 13(1): 19980, 2023 Nov 15.
Artículo en Inglés | MEDLINE | ID: mdl-37968286

RESUMEN

This paper presents comprehensive research of the advantages and applicability of various concrete carbonation detection methods. Employing a combination of Phenolphthalein indicator (PI), Thermogravimetric analysis (TGA), X-ray phase analysis (XRD), Fourier transform infrared spectroscopy (FTIR), and Quantitative calcium carbonate analysis (CA), a detailed comparison to determine the carbonation depth in the partial carbonation zone of concrete specimens is conducted. Among the quantitative analysis methods, CA measures CaCO3 content based on chemical reactions, while TGA obtains the concentration distribution of Ca(OH)2 and CaCO3. Among qualitative analysis methods, XRD tested the intensity distribution of Ca(OH)2 and CaCO3, while FTIR traced the characteristic peaks of C-O functional groups in a specific spectral range to determine the depth of carbonation of concrete. Results indicate that the depth of carbonation values measured by CA, TGA, XRDA, and FTIR are 2-3 times higher than those measured by PI. This research may provide valuable insights for the design of carbonation detection in concrete.

4.
J Microbiol ; 59(10): 949-957, 2021 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-34491523

RESUMEN

Streptococcus suis serotype 2 (S. suis 2) is an important zoonotic pathogen that presents a significant threat both to pigs and to workers in the pork industry. The initial steps of S. suis 2 pathogenesis are unclear. In this study, we found that the type II histidine triad protein HtpsC from the highly virulent Chinese isolate 05ZYH33 is structurally similar to internalin A (InlA) from Listeria monocytogenes, which plays an important role in mediating listerial invasion of epithelial cells. To determine if HtpsC and InlA function similarly, an isogenic htpsC mutant (ΔhtpsC) was generated in S. suis by homologous recombination. The htpsC deletion strain exhibited a diminished ability to adhere to and invade epithelial cells from different sources. Double immunofluorescence microscopy also revealed reduced survival of the ΔhtpsC mutant after co-cultivation with epithelium. Adhesion to epithelium and invasion by the wild type strain was inhibited by a monoclonal antibody against E-cadherin. In contrast, the htpsC-deficient mutant was unaffected by the same treatment, suggesting that E-cadherin is the host-cell receptor that interacts with HtpsC and facilitates bacterial internalization. Based on these results, we propose that HtpsC is involved in the process by which S. suis 2 penetrates host epithelial cells, and that this protein is an important virulence factor associated with cell adhesion and invasion.


Asunto(s)
Proteínas Bacterianas/metabolismo , Células Epiteliales/microbiología , Hidrolasas/metabolismo , Infecciones Estreptocócicas/microbiología , Infecciones Estreptocócicas/veterinaria , Streptococcus suis/metabolismo , Streptococcus suis/patogenicidad , Adhesión Bacteriana , Proteínas Bacterianas/genética , Humanos , Hidrolasas/genética , Streptococcus suis/genética , Virulencia
5.
Appl Opt ; 59(10): 3093-3096, 2020 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-32400590

RESUMEN

A dual-fiber point diffraction interferometer is built to measure the wavefront aberration of an imaging system with high precision. The optical intensity of the test light and reference light are controlled independently, so that high interference contrast can be obtained. The interferometer has several advantages: high precision, a flexible structure, and a quasi-common optical path. System errors of the interferometer that influence the measurement accuracy are considered and calibrated. In the experiments, a projection lens with numerical aperture of 0.3 is measured. The measured wavefront error is 1.5 nm rms, and the measurement repeatability is 35 pm rms.

6.
J Agric Food Chem ; 63(43): 9513-9, 2015 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-26416299

RESUMEN

Phytohemagglutin (PHA), purified from red kidney beans (Phaseolus vulgaris) by Affi-Gel blue affinity chromatography, was subjected to ultrahigh-pressure (UHP) treatment (150, 250, 350, and 450 MPa). The purified PHA lost its hemagglutination activity after 450 MPa treatment and showed less pressure tolerance than crude PHA. However, the saccharide specificity and α-glucosidase inhibition activity of the purified PHA did not change much after UHP treatment. Electrophoresis staining by periodic acid-Schiff (PAS) manifested that the glycone structure of purified PHA remained stable even after 450 MPa pressure treatment. However, electrophoresis staining by Coomassie Blue as well as circular dichroism (CD) and differential scanning calorimetry (DSC) assay proved that the protein unit structure of purified PHA unfolded when treated at 0-250 MPa but reaggregates at 250-450 MPa. Therefore, the hemagglutination activity tends to be affected by the protein unit structure, while the stability of the glycone structure contributed to the remaining α-glucosidase inhibition activity.


Asunto(s)
Culinaria/métodos , Phaseolus/química , Fitohemaglutininas/química , Semillas/química , Culinaria/instrumentación , Calor , Phaseolus/enzimología , Proteínas de Plantas/análisis , Presión , alfa-Glucosidasas/análisis
7.
J Agric Food Chem ; 63(29): 6525-34, 2015 Jul 29.
Artículo en Inglés | MEDLINE | ID: mdl-26155804

RESUMEN

Dictyophora indusiata polysaccharide (DP1) was successfully chelated with zinc chloride to achieve its enhanced antiproliferative activity. The obtained DP1-Zn complex showed significant antiproliferative activity (18.1 ± 2.84% viability of MCF-7 cells at 250 µg/mL) on a group of human cancer cell lines through induction of apoptosis. The pro-apoptotic action of DP1-Zn was confirmed by morphological changes including chromatin condensation, DNA breakage, and S phase cell cycle arrest in human breast adenocarcinoma cells (MCF-7). The DP1-Zn-induced apoptotic pathways were characterized by the activation of caspases-3, -8, and -9, mitochondrial dysfunction, and reactive oxygen species (ROS) overproduction (305 ± 7.06% production of control at 250 µg/mL). This study suggested that DP1-Zn can be developed as a candidate for cancer treatment and prevention, especially human breast adenocarcinoma.


Asunto(s)
Antineoplásicos/farmacología , Basidiomycota/química , Neoplasias de la Mama/tratamiento farmacológico , Polisacáridos/farmacología , Zinc/farmacología , Apoptosis/efectos de los fármacos , Neoplasias de la Mama/patología , Proliferación Celular/efectos de los fármacos , Humanos , Células MCF-7
8.
Rejuvenation Res ; 17(2): 209-11, 2014 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-24147434

RESUMEN

Ultrafiltration, ion-exchange chromatography, and gel filtration chromatography were used to purify anti-oxidant peptides from hydrolysates of soybean protein isolates. The <1-kD peptides were found to exhibit much higher anti-oxidant activity as compared to larger ones. Also, the alkaline peptide fractions were shown to have stronger anti-oxidant capacity than acidic and neutral peptides. Interestingly, an anti-oxidant tripeptide, Ser-Phe-Val (352.4 Da), was identified by reversed-phase high-performance liquid chromatography (RP-HPLC) connected online to electrospray ionization mass spectrometry. The tripeptide was further prepared by fluorenylmethoxycarbonyl (Fmoc) solid-phase synthesis and was found to have a dose-dependent protective effect against hydrogen peroxide (H2O2)-induced injuries in rat adrenal pheochromocytoma (PC12) cells.


Asunto(s)
Antioxidantes/aislamiento & purificación , Cromatografía Líquida de Alta Presión/métodos , Glycine max/química , Péptidos/aislamiento & purificación , Espectrometría de Masa por Ionización de Electrospray/métodos , Secuencia de Aminoácidos , Animales , Antioxidantes/química , Datos de Secuencia Molecular , Células PC12 , Péptidos/química , Ratas
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