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991.
Free and glycosidically bound volatile compounds of red wine were measured after malolactic fermentation (MLF) with four different commercial starter cultures of Oenococcus oeni. MLF resulted in a significant decrease in the concentration of total glycosides, expressed as phenol‐free glycosyl glucose. Gas chromatographic analyses of wine enzyme hydrolysates showed that the extent of hydrolysis of glycosides during MLF was dependent on both bacterial strain and chemical structure of the substrate. The highest decrease was observed for glycosidic precursors of primary terpene alcohols. Glycoside‐related aroma compounds such as linalool, farnesol, and β‐damascenone were increased after MLF with all the bacterial strains tested. Two of the strains were also able to release significant amounts of vinylphenols during MLF. Copyright © 2006 Society of Chemical Industry  相似文献   
992.
993.
The aim was to evaluate the effect of wine addition during manufacturing of dry fermented sausages, in terms of safety aspects (biogenic amine accumulation), aroma profile and sensory characteristics. Three batches of salami were produced: without wine addition and with 7.5% or 15% (v/w) of white wine. The fermented sausages showed characteristics that can increase product diversification. Some of the sensory features (i.e. increased salty perception) can represent an important strategy because of the trend to reduce salt intake for health reasons. The presence of wine immediately reduced the pH and is a source of ethanol, which can have an inhibitory effect against undesirable microflora. The microbiological results observed regarding Enterobacteriaceae and enterococci were encouraging. The addition of wine did not negatively affect the ripening time or increase the presence of biogenic amines. The samples containing wine showed reduced concentrations of putrescine.  相似文献   
994.

Purpose

To assess the accuracy of intraocular pressure (IOP) measurements using rebound tonometry over disposable hydrogel (etafilcon A) and silicone hydrogel (senofilcon A) contact lenses (CLs) of different powers.

Methods

The experimental group comprised 36 subjects (19 male, 17 female). IOP measurements were undertaken on the subject's right eyes in random order using a rebound tonometer (ICare). The CLs had powers of +2.00D, −2.00D and −6.00D. Six measurements were taken over each contact lens and also before and after the CLs had been worn.

Results

A good correlation was found between IOP measurements with and without CLs (all r ≥ 0.80; p < 0.05). Bland Altman plots did not show any significant trend in the difference in IOP readings with and without CLs as a function of IOP value. A two-way ANOVA revealed a significant effect of material and power (p < 0.01) but no interaction. All the comparisons between the measurements without CLs and with hydrogel CLs were significant (p < 0.01). The comparisons with silicone hydrogel CLs were not significant.

Conclusions

Rebound tonometry can be reliably performed over silicone hydrogel CLs. With hydrogel CLs, the measurements were lower than those without CLs. However, despite the fact that these differences were statistically significant, their clinical significance was minimal.  相似文献   
995.
Oleocanthal (OLC) is a phenolic component of extra-virgin olive oil, recently supposed to be involved in the modulation of some human diseases, such as inflammation and Alzheimer. In particular, OLC has been shown to abrogate fibrillization of tau protein, one of the main causes of Alzheimer neurodegeneration. A recent interpretation of this mechanism has been attempted on the basis of OLC reactivity with the fibrillogenic tau hexapeptide VQIVYK and SDS-PAGE of OLC/tau incubation mixtures, suggesting that covalent modification events modulate tau fibrillization. In this paper we report a detailed mass spectrometric investigation of the OLC reactive profile with both tau protein fibrillogenic fragment K18 and propylamine in biomimetic conditions. We show that K18 is prone to be covalently modified by OLC through Schiff base formation between the ε-amino group of lysine residues and OLC aldehyde carbonyls. Moreover, as expected from its de-structured conformation, K18 shows a non-selective modification profile, reacting with several lysine residues to give cyclic pyridinium-like stable adducts. These data give new insights on the mechanism of inhibition of tau fibrillization mediated by OLC.  相似文献   
996.
Multiple sclerosis (MS) is a neurodegenerative inflammatory condition mediated by autoreactive immune processes. Due to its potential to influence host immunity and gut-brain communication, the gut microbiota has been suggested to be involved in the onset and progression of MS. To date, there is no definitive cure for MS, and rehabilitation programs are of the utmost importance, especially in the later stages. However, only a few people generally participate due to poor support, knowledge, and motivation, and no information is available on gut microbiota changes. Herein we evaluated the potential of a brief high-impact multidimensional rehabilitation program (B-HIPE) in a leisure environment to affect the gut microbiota, mitigate MS symptoms and improve quality of life. B-HIPE resulted in modulation of the MS-typical dysbiosis, with reduced levels of pathobionts and the replenishment of beneficial short-chain fatty acid producers. This partial recovery of a eubiotic profile could help counteract the inflammatory tone typically observed in MS, as supported by reduced circulating lipopolysaccharide levels and decreased populations of pro-inflammatory lymphocytes. Improved physical performance and fatigue relief were also found. Our findings pave the way for integrating clinical practice with holistic approaches to mitigate MS symptoms and improve patients’ quality of life.  相似文献   
997.
998.
The Volterra-series expansion is widely employed to represent the input-output relationship of nonlinear dynamical systems. This representation is based on the Volterra frequency-response functions (VFRFs), which can either be estimated from observed data or through a nonlinear governing equation, when the Volterra series is used to approximate an analytical model. In the latter case, the VFRFs are usually evaluated by the so-called harmonic probing method. This operation is quite straightforward for simple systems but may reach a level of such complexity, especially when dealing with high-order nonlinear systems or calculating high-order VFRFs, that it may loose its attractiveness. An alternative technique for the evaluation of VFRFs is presented here with the goal of simplifying and possibly automating the evaluation process. This scheme is based on first representing the given system by an assemblage of simple operators for which VFRFs are readily available, and subsequently constructing VFRFs of the target composite system by using appropriate assemblage rules. Examples of wind and wave-excited structures are employed to demonstrate the effectiveness of the proposed technique.  相似文献   
999.
In this work we propose a new technological approach aimed at improving the performances of DNA-chips in terms of detection sensitivity, signal-to-noise ratio and parallel analyses (spatial and spectral). It is based on the efficient enhancement of markers fluorescence through the insertion of photonic crystal nanocavities (PhC) in DNA-chips, thus giving higher sensitivity and allowing detection of small amounts of target biomolecules in the investigated solution. Moreover, this strategy univocally associates a specific emission wavelength to a specific nanocavity (and to the bio-probe immobilized on it), therefore allowing to infer the presence of a determined element in the solution by a simple spectral analysis of the optical response of the read-out region. This guarantees parallel detection of multiple elements and faster analysis time. The proposed 2D-PhC cavity assisted bio-chip read-out can be easily extended from DNA to a wide range of biomolecules, such as proteins, antibodies, aptamers, receptors.  相似文献   
1000.
Results from both experimental measurements and 3D numerical simulations of Ground Source Heat Pump systems (GSHP) at a UK climate are presented. Experimental measurements of a horizontal-coupled slinky GSHP were undertaken in Talbot Cottage at Drayton St Leonard site, Oxfordshire, UK. The measured thermophysical properties of in situ soil were used in the CFD model. The thermal performance of slinky heat exchangers for the horizontal-coupled GSHP system for different coil diameters and slinky interval distances was investigated using a validated 3D model. Results from a two month period of monitoring the performance of the GSHP system showed that the COP decreased with the running time. The average COP of the horizontal-coupled GSHP was 2.5. The numerical prediction showed that there was no significant difference in the specific heat extraction of the slinky heat exchanger at different coil diameters. However, the larger the diameter of coil, the higher the heat extraction per meter length of soil. The specific heat extraction also increased, but the heat extraction per meter length of soil decreased with the increase of coil central interval distance.  相似文献   
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