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31.
Quality characteristics of low-salt bologna-type sausage manufactured with sodium citrate (NAC), carboxymethyl cellulose (CMC) and carrageenan (CAR) were examined. Three levels of salt, NAC, CMC and CAR, and two levels of fat were used. Batter and sausage pH values were measured and the frying loss of sausages was analysed by frying slices in an electric grill. Firmness, juiciness, saltiness and flavour intensity of the sausages were sensorically evaluated. Altogether 20 separate sausage batches were prepared. In low-salt sausages containing less than 1.4% NaCl, the use of NAC, CAR and CMC decreased frying loss and increased saltiness. NAC and CAR also increased flavour intensity, but CMC did not. Furthermore, NAC, CAR and CMC increased the firmness of the low-salt sausage, while only NAC increased juiciness when the NaCl content was below 1.4%. NAC increases, however, the sodium content of the product. Therefore, it can be concluded that in low-salt sausages no additive alone is suitable. A mixture of NAC and CAR appears to be the best combination.  相似文献   
32.
We present atomic force microscopy and scanning Kelvin probe data obtained under ultra-high vacuum conditions from graphene exfoliated on crystalline SrTiO(3) substrates. The contact potential difference shows a monotonic increase with the number of graphene layers until after five layers of saturation is reached. By identifying the saturation value with the work function of graphite we determine the work function of single and bilayer graphene to be Φ(SLG) = 4.409 ± 0.039 eV and Φ(BLG) = 4.516 ± 0.035 eV, respectively. In agreement with the higher work function of single-layer graphene with respect to free-standing graphene, our measurements indicate an accumulation of charge carriers corresponding to a doping of the exfoliated graphene layer with electrons.  相似文献   
33.
A breached nasal epithelial barrier plays an important role in driving allergic rhinitis (AR). Corticosteroids remain the standard of care (SoC) but come with side effects, thus alternative safe and effective treatments able to avoid inflammation and restore barrier integrity are needed. The aim of the present study is to evaluate the barrier-forming capacity of a xyloglucan-based nasal spray (XG) and compare its efficacy to several SoC treatments (corticosteroid spray, oral mast-cell stabilizer and oral antihistamine) in reducing allergic responses in addition to its effect when concomitantly administered with an antihistamine. An ovalbumin (OVA)-induced mouse AR model was used. XG shows a significant efficacy in reducing histological damage in AR mice; improves nasal rubbing and histamine-induced hyper-responsiveness. Total and OVA-specific IgE as well as pro-inflammatory cytokines are significantly reduced compared to OVA challenged-mice, with im-proved efficacy when used as an add-on treatment. However, XG reduces mucous secreting cells (PAS-positive) and mucin mRNA expression similar to the corticosteroid-treated mice. XG-spray maintains tight junction protein expression (ZO-1) and conversely decreases HDAC1 significantly; the latter being highly expressed in AR patients. Moreover, the concomitant treatment showed in all of the endpoints a similar efficacy to the corticosteroids. This innovative approach may represent a novel therapeutic strategy for nasal respiratory diseases like AR, reducing undesirable side effects and improving the quality of life in patients.  相似文献   
34.
In this paper, the effects of environmental stresses on the properties of polymeric optical waveguides were investigated. Optical multimode waveguides were embedded on printed circuit boards by employing commercial polymers. Three optical-PCB constructions varying in board structure and in optical build-up materials were compared. The guide systems were subjected to four different tests: damp heat-high humidity, isothermal annealing, thermal shock and environmental flowing multigas test. Isothermal annealing reduced the refractive index to greatest extent. The optical-PCB structure with optical surface build-up layer was observed to be more vulnerable under temperature shock when compared with the O-PCB with optical inner layer. The buffer layer beneath the optical build-up was found to improve the stability of the optical waveguides significantly. The results indicated of a wavelength dependence to the aging factor with a failure mechanism. The factors affecting the performance and reliability of polymer-based optical waveguides on PCBs were discussed.  相似文献   
35.
Using Tiffany's (1990) cognitive model of drug use and craving as a theoretical basis, the present experiments investigated whether cravings for food expend limited cognitive resources. Cognitive performance was assessed by simple reaction time (Experiment 1) and an established measure of working memory capacity, the operation span task (Experiment 2). In each experiment, female undergraduate students were randomly assigned to a craving or control condition. Participants in the craving condition abstained from eating chocolate for 24 hours prior to testing and performed the cognitive task in the presence of chocolate, a manipulation that successfully elicited chocolate cravings. In both experiments, there was no main effect of craving condition on cognition, but there was a significant interaction between condition and trait chocolate craving. In support of Tiffany's model, our results show that habitual food cravers direct limited cognitive resources to craving-related cues, at the cost of competing cognitive demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
36.
Traumatic brain injury (TBI) disrupts the blood–brain barrier (BBB). Vascular endothelial growth factor (VEGF) is believed to play a key role in TBI and to be overexpressed in the absence of apolipoprotein E (ApoE). Bevacizumab, a VEGF inhibitor, demonstrated neuroprotective activity in several models of TBI. However, the effects of bevacizumab on Apo-E deficient mice are not well studied. The present study aimed to evaluate VEGF expression and the effects of bevacizumab on BBB and neuroinflammation in ApoE−/− mice undergoing TBI. Furthermore, for the first time, this study evaluates the effects of bevacizumab on the long-term consequences of TBI, such as atherosclerosis. The results showed that motor deficits induced by controlled cortical impact (CCI) were accompanied by increased brain edema and VEGF expression. Treatment with bevacizumab significantly improved motor deficits and significantly decreased VEGF levels, as well as brain edema compared to the control group. Furthermore, the results showed that bevacizumab preserves the integrity of the BBB and reduces the neuroinflammation induced by TBI. Regarding the effects of bevacizumab on atherosclerosis, it was observed for the first time that its ability to modulate VEGF in the acute phase of head injury prevents the acceleration of atherosclerosis. Therefore, the present study demonstrates not only the neuroprotective activity of bevacizumab but also its action on the vascular consequences related to TBI.  相似文献   
37.
A method development and its validation are described for determining 31 selected Aspergillus, Fusarium, Penicillium, and Claviceps mycotoxins in small grain cereals (wheat, barley, oats). The method comprises an automated solvent extraction step followed by filtering, concentrating, and the analysis of the crude extract with liquid chromatographic-tandem mass spectrometric determination. The analytes included trichothecenes, zearalenone, fumonisins, moniliformin, enniatins, beauvericin, antibiotic Y, aflatoxins, ochratoxin A, mycophenolic acid, penicillic acid, and ergot alkaloids. These were separated in two consecutive chromatographic runs, both involving negative and positive electrospray ionization modes of mass spectrometry. The validation showed that the method performance was good for (semi-)quantitative work, limits of quantification varying between 1 and 1,250 μg kg−1, recoveries mostly between 51% and 122%, and repeatability being from 2% to 26% within day and from 14% to 28% between days (as relative standard deviation). A distinctive suppressive matrix effect, which depended on the analyte and the matrix, was observed but could be compensated for by using matrix-assisted standards. The developed multi-mycotoxin method permits simultaneous, simple, and rapid determination of several co-existing toxins and is ideal for, e.g., screening-type work or at concentration levels relevant in animal welfare. An erratum to this article can be found at  相似文献   
38.
Sediments formation and biogeochemical properties were studied in an experimental constructed wetland site in Ukraine (“Bioplato”) for treatment of domestic effluents. The wetland, with a capacity of 50 m3 d? 1 of wastewater, consists of vertical and horizontal filtrations units with fine gravel, middle and coarse sand, a subsurface flow unit with natural wetland soil applied, and a septic tank and sludge-drying field. Macrophytes, reed (Phragmites australis), cattail (Typha latifolia) and a number of sedge species (Carex spp.) were planted in the area and dominate the average cover of 85–90%. Treatment efficiency for BOD5 and suspended solids was 93–96%, for COD – 82%, for nutrients – 27–50%, and for pathogenic microorganisms 99.3–99.6%. Sludge was sampled at each unit followed by standard laboratory analyses of its main characteristics: total organic carbon (TOC), total nutrients (N, P), contents of trace elements, abundance of pathogenic microorganisms, and general toxicity. Results confirmed that the top layer of sludge from each unit of wetland could be used as a source of fertilizers for grain and leguminous crops.  相似文献   
39.
The mechanical properties of fibre composite materials are largely determined by the orientation of fibres within the matrix. Which orientation distribution short fibres follow in different parts of a structural element is still a subject for research and discussions in the scientific community. In this article, we present a modern and advanced method for measuring the orientation of short fibres in steel fibre-reinforced concrete (SFRC) by X-ray microtomography. With this method, a voxel image of the fibres is obtained directly in 3D, and the orientation of each individual fibre is calculated based on a skeletonized representation of this image. Scans of 12 SFRC samples, taken from the central height region of real-size floor slabs, reveal the fibres to be mostly horizontally oriented near the centre of a floor slab and more vertically oriented near the edge; here the alignment with the formwork dominates. The fibre orientation distributions are characterized by several orientation parameters as quantitative measures for the alignment. On the practical side, this method has the potential to be incorporated into the development and production process of SFRC structures to verify how the fibres contribute to capacity.  相似文献   
40.
Naturalistic driving studies are increasingly applied in different shapes and sizes. The European project PROLOGUE has investigated the value and feasibility of a large-scale naturalistic driving study in Europe. Within PROLOGUE several pilot studies have been conducted in different countries. The Dutch field trial investigated the value and feasibility of adding site-based observations to in-vehicle observations.  相似文献   
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