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81.
82.
The perception of texture has been correlated to the microstructure of particulate whey protein gels. A full, two-level, factorial experimental design was used in which the processing conditions, pH, heating rate and addition of salt were used as design factors. The texture of the gels was analysed by a sensory panel, and the microstructure was analysed by light and electron microscopy. The microstructure was quantified by using different types of image analysis.

In this study of particulate whey protein gels, the test principles of analysing texture were divided into two groups: destructive tests and non-destructive tests. The microstructural parameters can also be divided into two groups: overall network dimensions (pore size and particle size) and strand characteristics. The texture as measured with destructive methods was sensitive to overall network dimensions, whereas texture as measured with non-destructive methods was sensitive to the strand characteristics of particulate protein gels.  相似文献   

83.
This study was designed to establish whether phonological working memory skills could be assessed in children below 4 yrs of age. A group of 2- and 3-yr-old children were tested on 3 phonological memory measures (digit span, nonword repetition, and word repetition) and were also given tasks that tapped other cognitive skills. Scores on the 3 phonological memory tasks were closely related. In addition, repetition performance was linked with both vocabulary knowledge and articulation rate. Results indicate that phonological memory skills can be reliably assessed in very young children by using conventional serial span and repetition procedures. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
84.
Two series of water-soluble dendritic catanionic assemblies, acting as multisite analogues of galactosylceramide (Galbeta1cer), have been prepared with the goal of blocking HIV infection prior to the entry of the virus into human cells. Trifunctional and hexafunctional cinnamic acid-terminated dendrimers have been synthesized from phosphorus-containing dendrimers bearing aldehyde end groups. A classical acid-base reaction performed in water between acid-terminated dendrimers and stoichiometric amounts of N-hexadecylamino-1-deoxylactitol provided the expected catanionic assemblies. Antiviral assays on these supramolecular entities confirmed the crucial roles both of multivalency effects and of lipophilicity on the biological activity of Galbeta1cer analogues. Moreover, correlation between in vitro tests and molecular modeling highlights the specific influence of the assembly shape on the anti-HIV efficiency, with the tri- and hexafunctional cored dendrimers, both decorated with 12 sugar moieties, exhibiting IC50 values of 1.1 and 0.12 microM, respectively.  相似文献   
85.
The electrochemical reduction of nitrobenzene has been studied in the presence of some anionic, cationic and non-ionic surfactants using a glassy carbon electrode or a dropping mercury electrode (polarography). The results are depending upon the electrode nature, the surfactant polarity and the pH of the solutions.On glassy carbon electrode and with cationic surfactants, the reduction is always a one step process for the totality of the studied pH scale (2–12). With the anionic and non-ionic surfactants, the potential is shifted towards the more negative values for a one step process or for a two step process, according to the pH value.For the polarographical studies, the electrochemical reduction of nitrobenzene is generally retarded by the presence of monomer surfactant molecules adsorbed on the mercury electrode, principally in acid media. In micellar solutions, the CTAB decreases the protonation rate of the nitrobenzene radical anion and facilitates the reduction by a dianion way. The anionic and non-ionic surfactants increase the radical anion stability and slow down the rate of the radical anion reduction.  相似文献   
86.
The transformation of near-surface material on grinding and polishing has been investigated in sintered zirconia of 1 μm grain size and 99 % density containing 4.5 and 7.0 mol % Y2O3. Rough wet and dry grinding transformed ca 20 % cubic phase into 18 % tetragonal and 2 % monoclinic in material initially 47 % cubic and 53 % tetragonal (4.5 mol % Y2O3) but no change of phase in material that was fully cubic (7.0 mol % Y2O3). Annealing and polishing reduced lattice strain but only polishing reduced the concentration of monoclinic and tetragonal phases. Microhardness studies indicated that lattice strain and the phase transformations increased the penetration hardness to a depth of ca 4 μm.  相似文献   
87.
In this study, we have investigated the postoperative plasma consequences of coral implantation into femoral condyle of rabbits. Analyses were performed using Fourier transform infrared (FT-IR) spectroscopy, a sensitive and nondestructive method, to evaluate plasma modifications one day, one week, one month, and three months after surgery. This technique showed that both surgery and implantation induced important changes of lipidic compounds one day after surgery, with a body lipolysis. Major modifications appeared one week after surgery, with a decrease of protein and saccharide contents, and an increase of amino acids accompanied by a noticeable inflammatory process. These last changes were revealed by a hierarchical classification in the 1430-1295 and 1137-1092 cm(-1) spectral regions, leading to two well-separated groups, before and one week after surgery. After a delayed time of three months and despite a substantial recovery for biomolecules such as proteins and fatty acids, some alterations are always observed, such as for amino acids, triglycerides, and glycerol. Moreover, molecules implicated in the inflammatory process had not reached their initial level.  相似文献   
88.
Landscape issues are of interest in many disciplines, but they are seldom seen as an opportunity for inter- or transdisciplinary cooperation. This limits the ability to account for real world complexity. Bridging human and natural sciences intends to foster and coordinate communication about landscape-related issues—within academia and between science and society. The collection of papers in this special issue and the recommendations for future research are selected from the conference “Multifunctional Landscapes—Interdisciplinary Approaches to Landscape Research and Management” in Roskilde, Denmark, 2000. The contributions all bear evidence of an integrating approach to landscape research, bridging human and natural sciences.  相似文献   
89.
Over the past two decades, a significant number of studies in the United States, Canada and Europe have attempted to identify links between neighbourhood characteristics and antisocial behaviour of children and adolescents. Despite the abundance of work, the question of the choice of spatial scale has received little attention. Indeed, few studies have used different scales simultaneously in order to identify the most relevant scale. The aim of our study is precisely to identify the spatial scale in the most convincing explanation of antisocial behaviour violent and nonviolent in mid-adolescence and to better understand whether these are the characteristics of the immediate social environment at home or those of a much larger space that best explain the frequency of these behaviours. Using data from the a Montreal longitudinal study (ELEM) for 1037 boys from neighborhood socioeconomically disadvantaged, we tested the influence of different spatial scales defined from buffer zones (5, 10, 15, 20 and 30 minutes walk) from the residence of the child. The results show a significant relationship between low socioeconomic area and violent behaviour regardless of the spatial scale used. However, this relationship is significantly stronger for the smaller spatial units. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
90.
Plasmon resonance of gold nanoparticles is responsible of the electromagnetic (EM) Surface Enhanced Raman Scattering (SERS) effect. Interaction of an amorphous matrix with a SERS substrate was studied. Thin films with different thickness of amorphous TiO2 coated on a Klarite® substrate show a 100 times enhancement of the Raman signal. Distance dependence of the SERS interaction was shown to be less than 60 nm.  相似文献   
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