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141.
Sweet taste preference and personality traits using a white wine   总被引:1,自引:0,他引:1  
Understanding the influences of food and drink consumption patterns could help elucidate the factors that promote healthy dietary practices. Research has begun to investigate the influence of personality traits on dietary decisions. The current experiment measured personality traits and sweet taste preference using white wine in a healthy sample of adults (n = 45). Sweet taste preference was associated with a higher level of impulsiveness but lower openness. These traits have previously been suspected to influence dietary choices [Davis, C., Strachan, S., & Berkson, M. (2004). Sensitivity to reward: Implications for overeating and overweight. Appetite, 42, 131–138; Goldberg, L. R., & Strycker, L. A. (2002). Personality traits and eating habits: The assessment of food preferences in a large community sample. Personality and Individual Differences, 32, 49–65] and are briefly discussed within this context.  相似文献   
142.
A collection of lactic acid bacteria isolated from both mayonnaise-based products and raw materials used to manufacture them was tested for antimicrobial activity. Out of 144 strains (97 lactobacilli, 23 lactococci and 24 enterococci) only three supernatants of Enterococcus spp. strains (EN3, EN14 and EN15) exhibited activity against lactobacilli and lactococci. The supernatant of the strain EN3 exclusively inhibited the growth of Bacillus cereus and Listeria monocytogenes. Enterococcus strains EN3, EN14 and EN15 produced thermostable bacteriocins, which had antibacterial activity.  相似文献   
143.
We have developed a new numerical model for the non-steady-state operation of the Droplet Measurement Technologies (DMT) Cloud Condensation Nuclei (CCN) counter. The model simulates the Scanning Flow CCN Analysis (SFCA) instrument mode, where a wide supersaturation range is continuously scanned by cycling the flow rate over 20–120 s. Model accuracy is verified using a broad set of data which include ammonium sulfate calibration data (under conditions of low CCN concentration) and airborne measurements where either the instrument pressure was not controlled or where exceptionally high CCN loadings were observed. It is shown here for the first time that small pressure and flow fluctuations can have a disproportionately large effect on the instrument supersaturation due to localized compressive/expansive heating and cooling. The model shows that, for fast scan times, these effects can explain the observed shape of the SFCA supersaturation-flow calibration curve and transients in the outlet droplet sizes. The extent of supersaturation depletion from the presence of CCN during SFCA operation is also examined; we found that depletion effects can be neglected below 4000 cm?3 for CCN number.

Copyright 2014 American Association for Aerosol Research  相似文献   
144.
145.
ABSTRACT

Pellets containing drugs of different properties were prepared in a Rotoprocessor in order to study changes in the formulation process and resulting pellet characteristics. Diltiazem hydrochloride, diclofenac sodium, and theophylline were chosen as model drugs. Pellet size distribution, sphericity, density, hardness, friability, and repose angle were determined using standard methods. The amount of water as a wetting agent necessary for successful pellet formulation was observed for each sample and changed depending on drug solubility, concentration, and particle size. The pelletization of freely soluble diltiazem hydrochloride required 24.8–23.1% of the wetting agent and its amount decreased as the drug concentration increased. The demand for water in the formulation of theophylline pellets was 31.0–34.4% and it increased with increasing drug concentration. The pellet samples containing both drugs were easy to prepare. However, the cohesion of micronized diclofenac sodium particles negatively influenced both the pellet size distribution and the formulation process itself. When the drug concentration exceeded 40%, it was not possible to produce pellets of an appropriate size and the process was not reproducible.  相似文献   
146.
147.
Colabomycin E is a new member of the manumycin‐type metabolites produced by the strain Streptomyces aureus SOK1/5‐04 and identified by genetic screening from a library of streptomycete strains. The structures of colabomycin E and accompanying congeners were resolved. The entire biosynthetic gene cluster was cloned and expressed in Streptomyces lividans. Bioinformatic analysis and mutagenic studies identified components of the biosynthetic pathway that are involved in the formation of both polyketide chains. Recombinant polyketide synthases (PKSs) assembled from the components of colabomycin E and asukamycin biosynthetic routes catalyzing the biosynthesis of “lower” carbon chains were constructed and expressed in S. aureus SOK1/5‐04 ΔcolC11–14 deletion mutant. Analysis of the metabolites produced by recombinant strains provided evidence that in both biosynthetic pathways the length of the lower carbon chain is controlled by an unusual chain‐length factor supporting biosynthesis either of a triketide in asukamycin or of a tetraketide in colabomycin E. Biological activity assays indicated that colabomycin E significantly inhibited IL‐1β release from THP‐1 cells and might thus potentially act as an anti‐inflammatory agent.  相似文献   
148.
Silicon nanocrystals (Si-ncs) are promising for biological studies due to their supposed low cytotoxicity, good biocompatibility and biodegradability in living organisms. However, the bioresearchers'' focus on Si-ncs has lasted only for a few recent years, and detailed studies of the interaction of various types of Si-ncs with biological environment are still rare. Suitable size and solubility of the Si-ncs in water-based isotonic solutions are important towards bringing the nanocrystals inside the living cells. We have prepared colloidal solutions of luminescent porous silicon of different cluster sizes in methanol, water and phosphate-buffered saline (PBS). By combination of ultrasonic treatment with filtration, we have obtained two different silicon cluster sizes in methanol (120 and 525 nm) and three different cluster sizes (85, 210 and 1,500 nm) in PBS. Nanoclusters of heavily oxidized porous silicon are hydrophilic and well soluble in water and/or PBS. They can be further used for studies on the biocompatibility of these materials and may be potentially employed as luminescent markers in living cells in biological research.

PACS

78.67.Rb; 78.67.-n; 87.85.Qr; 87.85.Rs; 81.07.-b  相似文献   
149.
Wear performance of automotive brake material is addressed and debris collected after brake dynamometer test and after ball-milling of identical semimetallic friction lining is characterized using a combination of analytical techniques. The differences between dynamometer wear debris and ball-milled samples are demonstrated. Wear debris is typified by the presence of numerous nanoparticles formed during wear process. Their chemistry resembles the chemistry of friction layer described previously. Contradicting findings by different research groups addressing automotive wear particulates are discussed and further refinement of analytical and testing techniques as well as their combination is suggested.  相似文献   
150.
There is evidence that excessive speed leads to an increased frequency and severity of road traffic accidents, but it is not clear how speeds may be reduced. To increase understanding of why drivers exceed the speed limits, the views of a sample of road users who had been prosecuted for exceeding the speed limit in the rural county of Norfolk England were sought. Respondents were categorised into a four group driver typology comprising conformers (those who report they never exceed limits) deterred drivers (those put off speeding by the presence of cameras), manipulators (those who slow only at camera locations) and defiers (those who exceed limits regardless of cameras), and the consistency of opinions was compared between the groups. Speeding was perceived as widespread and normal, and many drivers resented camera enforcement. Indeed, some respondents considered that cameras in themselves caused dangerous driving. For many drivers, the prosecution experience resulted in distress, anger and anti-camera sentiments, predominantly because they expressed the belief that they were more skilled than other drivers. It was also apparent that many respondents displayed a lack of awareness of the link between speed and collisions. Conformers were the least likely to state that the prosecution had deterred them from further speeding behaviour, possibly because they perceived themselves as already law-abiding. The deterred drivers were most likely to express intentions to avoid further speeding and their speeding incident was found to be most likely to be accidental. Manipulators and defiers tended to report that they had deliberately chosen to infringe the speed limits. Manipulators often acknowledged that their style of driving was dangerous; however, they failed to link this to their own behaviour. It was evident that many defiers and manipulators did not perceive speeding as a serious traffic law violation. Possible implications for road safety initiatives are discussed and recommendations are given for specifically targeting different driver types.  相似文献   
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