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131.
132.

Purpose

To report an unusual case of recurrent episcleritis secondary to IgA nephropathy.

Design

Observational case report.

Methods

A 39-year-old man was seen with recurrent episodes of red and painful left eye suggestive of episcleritis.

Results

On routine investigations the patient was found to have haematuria and proteinuria. Further investigations led to the diagnosis of IgA nephropathy on kidney biopsy.

Conclusion

IgA nephropathy may present with various eye signs without any other systemic clues. This case highlights the importance of some of the basic tests in clinical practice such as urine examination. This can be conveniently done with testing strip and should be considered in the routine investigation of patients with inflammatory eye diseases.  相似文献   
133.
Silicon carbide is a ceramic material that has been widely studied because of its potential applications, ranging from electronics to heterogeneous catalysis. Recently, a new type of SiC materials with a medium specific surface area and thermal conductivity, called β-SiC, has attracted overgrowing interest as a new class of catalyst support in several catalytic reactions. A primary electron tomography study, performed in usual mode, has revealed a dual surface structure defined by two types of porosities made of networks of connected channels with sizes larger than 50 nm and ink-bottled pores with sizes spanning from 4 to 50 nm. Depending on the solvent nature, metal nanoparticles could be selectively deposited inside one of the two porosities, a fact that illustrates a selective wetting titration of the two types of surfaces by different liquids. The explaining hypothesis that has been put forward was that this selectivity against solvents is related to the pore surface oxidation degree of the two types of pores. A new technique of analytical electron tomography, where the series of projections used to reconstruct the volume of an object is recorded in energy filtered mode (EFTEM), has been implemented to map the pore oxidation state and to correlate it with the morphology and the accessibility of the porous network. Applied, for the first time, at a nanoscale resolution, this technique allowed us to obtain 3D elemental maps of different elements present in the analysed porous grains, in particular oxygen; we found thus that the interconnected channel pores are more rapidly oxidized than the ink-bottled ones. Alternatively, our study highlights the great interest of this method that opens the way for obtaining precise information on the chemical composition of a 3D surface at a nanometer scale.  相似文献   
134.
Macadamia nut industry is increasingly gaining more space in the food market and the success of the industry and the quality are largely due to the selection of cultivars through macadamia nut breeding programs. Thus, the objective of this study was to investigate the feasibility NIRS coupled to chemometric classification methods, to build a rapid and non-invasive analytical procedure to classify different macadamia cultivars based on intact nuts. Intact nuts of five different macadamia cultivars (HAES 246, IAC 4-20, IAC 2-23, IAC 5-10, and IAC 8-17) were harvested in 2017. Two NIR reflectance spectra were collected per nut, and the mean spectra were used to chemometrics analysis. Principal component analysis-linear discriminant analysis (PCA-LDA) and genetic algorithm-linear discriminant analysis (GA-LDA) were used to develop the classifications models. The GA-LDA approach resulted in accuracy higher than 94.44%, with spectra preprocessed with Savitzky-Golay smoothing. Thus, this approach can be implemented in the macadamia industry, allowing the selection of cultivars based on intact nuts. However, it is recommended that more experimentation to include more data variability in order to increase the classification accuracy to 100%.  相似文献   
135.
Reactive carbonyl species (RCS) such as methylglyoxal (MGO) or glyoxal (GO) are the main precursors of the formation of advanced glycation end products (AGEs). AGEs are a major factor in the development of vascular complications in diabetes. Vasoprotectives (VPs) exhibit a wide range of activities beneficial to cardiovascular health. The present study aimed to investigate selected VPs and their structural analogs for their ability to trap MGO/GO, inhibit AGE formation, and evaluate their antioxidant potential. Ultra-high-performance liquid chromatography coupled with an electrospray ionization mass spectrometer (UHPLC-ESI-MS) and diode-array detector (UHPLC-DAD) was used to investigate direct trapping capacity and kinetics of quenching MGO/GO, respectively. Fluorimetric and colorimetric measurements were used to evaluate antiglycation and antioxidant action. All tested substances showed antiglycative effects, but hesperetin was the most effective in RCS scavenging. We demonstrated that rutin, diosmetin, hesperidin, and hesperetin could trap both MGO and GO by forming adducts, whose structures we proposed. MGO-derived AGE formation was inhibited the most by hesperetin, and GO-derived AGEs by diosmetin. High reducing and antiradical activity was confirmed for quercetin, rutin, hesperetin, and calcium dobesilate. Therefore, in addition to other therapeutic applications, some VPs could be potential candidates as antiglycative agents to prevent AGE-related complications of diabetes.  相似文献   
136.
The study discusses the necessity to analyze the influence of theoretical and empirical types of journal articles on the citation impact of Spanish psychology journals. Three of the most representative Spanish psychology journals were selected for the purposes of this study: Papeles del Psicólogo, Análisis y Modificación de Conducta and Psicothema. Twenty-three psychology journals in Spanish were used as source journals. Altogether, there were sixty-seven issues reviewed for the references and ninety-three issues for the articles. The bibliometricanalysis was conducted by six highly trained psychologists. The results demonstrated differences regarding the percentages of empirical and theoretical articles published in the three examined journals and the number of citations received by them based on the article type. When normalizing the results according to the number of theoretical and empirical articles that were published, it becomes evident that the theoretical articles receive on average twice as many references as the empirical ones. We discuss the importance of this effect on the comparison of journals based on their citation impact and show the evidence that it is only valid to compare journals which publish a similar percentage of theoretical and empirical articles.  相似文献   
137.
The paper presents a general method to evaluate a masonry structure with a complex geometry and unknown material properties. This multidisciplinary approach integrates close range digital photogrammetry, ground probing radar (GPR) and finite elements analysis (FEM) to analyse a masonry bridge. The resulting information from photogrammetry and radar is applied to define a 3D model, which is then used to simulate the behaviour of the bridge using FEM. Two different approaches to model the internal composition of the bridge with finite elements are presented. Sensitivity analysis is applied to study the reasons of the structural damage.  相似文献   
138.
Cascade simulations in single crystal and nanocrystalline SiC have been conducted in order to determine the role of grain boundaries and grain size on defect production during primary radiation damage. Cascades are performed with 4 and 10 keV silicon as the primary knock-on atom (PKA). Total defect production is found to increase with decreasing grain size, and this effect is shown to be due to increased production in grain boundaries and changing grain boundary volume fraction. In order to consider in-grain defect production, a new mapping methodology is developed to properly normalize in-grain defect production rates for nanocrystalline materials. It is shown that the presence of grain boundaries does not affect the total normalized in-grain defect production significantly (the changes are lower than ~20%) for the PKA energies considered. Defect production in the single grain containing the PKA is also studied and found to increase for smaller grain sizes. In particular, for smaller grain sizes the defect production decreases with increasing distance from the grain boundary while for larger grain sizes the presence of the grain boundaries has negligible effect on defect production. The results suggest that experimentally observed changes in radiation resistance of nanocrystalline materials may be due to long-term damage evolution rather than changes in defect production rates from primary damage.  相似文献   
139.
HPLC and HPTLC methods were used for a qualitative and quantitative determination of luteolin-7-O-β-glucuronide, lithospermic acid, rosmarinic acid and mthyl rosmarinate, together with other known compounds, in commercial herbal drugs and spices from lamiaceous species: Thymi herba, Serpylli herba and Majoranae herba. The contents of analyzed compounds in the studied hydrophilic extracts, prepared form herbal sources, were established using a C18 column with acetonitrile–water–formic acid as a mobile phase. The HPLC method was validated for linearity, precision and accuracy. Luteolin-7-O-β-glucuronide and lithospermic acid were identified as new wild thyme constituents, luteolin-7-O-β-glucuronide and methyl rosmarinate as new compounds in sweet marjoram. Methyl rosmarinate was isolated for the first time from thyme. The investigated herbal drugs and spices provide polyphenols in high amounts, even up to 84.3 mg per 1 g of a dried herb.  相似文献   
140.
Adsorption of specifically designed and geometrically constrained polyaromatic amphiphiles on single-walled carbon nanotubes (SWNTs) was found to be selective of the nanotube helicity angle. Starting from the same SWNT mixture, photoluminescence and resonant Raman spectroscopies show that a pentacenic-based amphiphile leads to the solubilization of armchair SWNTs and that a quaterrylene-based amphiphile leads to the solubilization of zigzag SWNTs. The results were predicted by the design of the two amphiphiles and are consistent with a supramolecular recognition of the nanotube graphene-type atomic structure by the aromatic part of the molecules through optimized pi-pi-stacking interactions.  相似文献   
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