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91.
Three different NIR equipment were evaluated based on their ability to predict superficial water activity (a(w)) and moisture content in two types of fermented sausages (with and without moulds on surface), using partial least squares (PLS) regression models. The instruments differed mainly in wavelength range, resolution and measurement configuration. The most accurate equipment was used in a new experiment to achieve robust models in sausages with different salt contents and submitted to different drying conditions. The models developed showed determination coefficients (R(2)(P)) values of 0.990, 0.910 and 0.984, and RMSEP values of 1.560%, 0.220% and 0.007% for moisture, salt and a(w) respectively. It was demonstrated that NIR spectroscopy could be a suitable non-destructive method for on-line monitoring and control of the drying process in fermented sausages. 相似文献
92.
This study focused on the metal bioaccumulation of two aquatic insects (Ephoron virgo and Hydropsyche spp.) in order to evaluate the spatial distribution of metals, the interspecific differences between both filter-feeders and the bioaccumulation dynamics during E. virgo development stages. Hg, Cd, Ni, Cr, As, Pb, Cu, Ti, Zn and Mn were quantified in insects and in suspended particulate matter (SPM) sampled downstream and upstream of a chemical plant, where more than 300,000 t of polluted sediments are deposited. Hg concentrations were one order of magnitude higher downstream of the sediment dump, which showed that the Hg pollution originated in the chemical plant. Cd, Ni, Cr, Pb, Ti, Zn and Mn in invertebrates revealed that metal pollution was present upstream in other parts of the river. Interspecific differences were observed for all metals but Mn; significantly higher concentrations were observed in E. virgo over Hydropsyche exocellata, except for Cd, which showed 10-fold higher values. Hg and Cd increased until E. virgo nymphs reached 11 mm and decreased afterwards in late instars when nymphs were about to emerge. Cr, Pb, Ti and Mn decreased along early instars followed by a steady state in late instars. Similar values were obtained for Cu, As and Zn along all instars. Sexual differences between males and females of E. virgo were observed for Cd, Cu and Mn. Hg and Cd persistence was strong across developmental stages since high concentrations were found in eggs and emerging adults. Because the behavior of different metals varied for the two species and during the developmental stages of E. virgo, care should be taken in the interpretation of insect metal concentrations when analyzing the food chain transfer of metals in river ecosystems. 相似文献
93.
Phytosterol‐mediated inhibition of intestinal cholesterol absorption in mice is independent of liver X receptor
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94.
Pareto D Aguiar P Pavía J Gispert JD Cot A Falcón C Benabarre A Lomeña F Vieta E Ros D 《IEEE transactions on bio-medical engineering》2008,55(7):1849-1853
Statistical parametric mapping (SPM) has become the technique of choice to statistically evaluate positron emission tomography (PET), functional magnetic resonance imaging (fMRI), and single photon emission computed tomography (SPECT) functional brain studies. Nevertheless, only a few methodological studies have been carried out to assess the performance of SPM in SPECT. The aim of this paper was to study the performance of SPM in detecting changes in regional cerebral blood flow (rCBF) in hypo- and hyperperfused areas in brain SPECT studies. The paper seeks to determine the relationship between the group size and the rCBF changes, and the influence of the correction for degradations. The assessment was carried out using simulated brain SPECT studies. Projections were obtained with Monte Carlo techniques, and a fan-beam collimator was considered in the simulation process. Reconstruction was performed by using the ordered subsets expectation maximization (OSEM) algorithm with and without compensation for attenuation, scattering, and spatial variant collimator response. Significance probability maps were obtained with SPM2 by using a one-tailed two-sample f-test. A bootstrap resampling approach was used to determine the sample size for SPM to detect the between-group differences. Our findings show that the correction for degradations results in a diminution of the sample size, which is more significant for small regions and low-activation factors. Differences in sample size were found between hypo- and hyperperfusion. These differences were larger for small regions and low-activation factors, and when no corrections were included in the reconstruction algorithm. 相似文献
95.
Strength of bearing connections in toughened glass plates for the structural use. In steel structures due to their “infinite'” ductility the bearing connections are standard components of joints. Their design rules are based on simple engineering models. However if analogous bearing connections are subject of glazing structures the requirements on the materials' ductility cannot be met. Therefore interlayers out of mortar etc. in the hole surrounding the bolt have to be introduced such that a ductile load deformation behaviour can be reached reducing stress peaks and avoiding steel‐glass‐contact. On this basis design rules are to be established to predict the load carrying capacity of bolts in glass bearings. The following investigations describe the experimental and theoretical works to derive an engineering model for this purpose. 相似文献
96.
<正>热烫是植物性食品进行各种贮藏加工(冷冻,冻干,杀菌,脱水)之前的热处理工序。常见的热烫工序是把蔬菜或水果浸入开水或放入 95~100℃的热蒸汽中,热烫时间视使用技术和果蔬数量而异。热烫所起的作用因贮藏方法不同相差很大。 相似文献
97.
98.
Hannan Tahir Ioana Niculescu Carles Bona-Casas Roeland M. H. Merks Alfons G. Hoekstra 《Journal of the Royal Society Interface》2015,12(108)
Excessive migration and proliferation of smooth muscle cells (SMCs) has been observed as a major factor contributing to the development of in-stent restenosis after coronary stenting. Building upon the results from in vivo experiments, we formulated a hypothesis that the speed of the initial tissue re-growth response is determined by the early migration of SMCs from the injured intima. To test this hypothesis, a cellular Potts model of the stented artery is developed where stent struts were deployed at different depths into the tissue. An extreme scenario with a ruptured internal elastic lamina was also considered to study the role of severe injury in tissue re-growth. Based on the outcomes, we hypothesize that a deeper stent deployment results in on average larger fenestrae in the elastic lamina, allowing easier migration of SMCs into the lumen. The data also suggest that growth of the neointimal lesions owing to SMC proliferation is strongly dependent on the initial number of migrated cells, which form an initial condition for the later phase of the vascular repair. This mechanism could explain the in vivo observation that the initial rate of neointima formation and injury score are strongly correlated. 相似文献
99.
100.
Research has shown that resource allocation in a dyad sometimes follows the principle of equity (proportional reward) and sometimes that of parity (equal reward). However, existing evidence does not clarify the conditions under which each of these rules is invoked. A number of theorists have suggested that salience of the other as a person should lead to parity-based allocation, whereas salience of the other as a functionary filling a role should lead to equity-based allocation. The present study with 60 male and 60 female undergraduates tested these possibilities. Ss were led to perceive their own inputs to group performance as being either substantially lower or substantially higher than a partner's inputs. The partner had been portrayed to the S in terms that made salient the partner's personal characteristics, the partner's role assignment, or neither of these. Among females, subsequent reward allocation followed the predicted pattern in both high- and low-input conditions. Among males, contrary to expectation, person salience led to heightened feelings of competitiveness and to increased allocations to the self. (22 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献