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41.
A laboratory medium inoculated with 20 different Staphylococcus strains was prepared in accordance with a full factorial experimental design investigating the effect of temperature, pH, NaCl and glucose on growth. The 12 strains most suited to growth in a fermented meat environment were inoculated in sausage minces together with Pediococcus pentosaceus, incubated at 25 degrees C for 1 week and the produced aroma compounds collected. The data were analysed by multiple linear regression and partial least squares regression analysis. The results showed that increasing pH and temperature from 4.6 to 6.0 and 10 to 26 degrees C, respectively, increased growth of all strains with strong synergy between temperature and pH. Increasing salt concentration from 5% to 15% w/v decreased growth of most strains, but the effect of pH and temperature was much stronger than the effect of salt. Strains of S. carnosus were more salt tolerant than strains of S. equorum and S. xylosus, especially at high pH and temperature. Addition of glucose up to 0.5% w/v had no significant influence on growth of any of the strains. With regard to aroma production, species characteristics were detected. S. carnosus and S. xylosus were quite different regarding the overall aroma profiles, whereas the profiles of S. equorum lied somewhere in-between. Contrary to S. carnosus, S. xylosus and S. equorum did not produce 2-methyl-1-butanol. On the other hand, in particular, S. xylosus produced more 3-methyl-1-butanol. Except for one of the strains of S. equorum, S. xylosus and S. equorum formed more diacetyl, 2-butanone and acetoin and also more of the methyl-branched ketones arising from degradation of leucine, isoleucine and valine. S. carnosus produced more methyl-branched aldehydes, acids and corresponding esters from leucine, isoleucine and valine compounds that have been correlated with fermented sausage maturity in former studies. S. equorum produced the least of the methyl-branched aldehydes. 相似文献
42.
How can schools and parents work together more effectively? This article describes a participatory action research (PAR) project with a group of parents whose children had been classified as having emotional disabilities. As the parents shared their stories of trying to navigate the special education system, they developed critical consciousness about their experiences of stress, powerlessness, and alienation. They became mobilized and obtained information about testing, diagnostic classification, and educational options for their children. Armed with this information, they developed and implemented an action plan to improve family-school relationships at the local, community, and state levels. The article concludes with an example of how the PAR model can be exported to a variety of mental health settings. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
43.
Xianmin Chang Peter G Alderson Tracey A Hollowood Louise Hewson Charles J Wright 《Journal of the science of food and agriculture》2006,86(14):i-vi
Retraction: The following article from the Journal of the Science of Food and Agriculture , ‘Temperature affects flavour intensity and quality of aroma in fresh basil (Ocimum basilicum L.) leaves’ by Xianmin Chang, Peter G Alderson, Tracey A Hollowood, Louise Hewson, and Charles J Wright, published online on 19 October 2005 in Wiley InterScience (www.interscience.wiley.com), has been retracted by agreement between the authors, the journal Editor in Chief, David S. Reid and John Wiley & Sons, Ltd. The retraction has been agreed due to overlap between this article and the following article published in the The Journal of Horticultural Science & Biotechnology ; ‘Effect of temperature integration on the growth and volatile oil content of Basil (Ocimum basilicum L.)’ by Xianmin Chang, Peter G Alderson and Charles J Wright. Volume 80 Issue 5, 2005, pages 593 – 598 相似文献
44.
Studied the development and validity of an instrument designed to measure stress by evaluating subjective feelings of stress without referring to "stress" or "stressors." Human subjects: 696 male and female Canadian adults, divided into 6 groups. Group I (15 Ss) were asked to provide a list of stress indicators for themselves, their spouses, and others. These indicators were used to establish the content validity of the Mesure de Stress Psychologique (MSP) ("Psychological State of Stress Measure"). Group II (98 university students) Ss were given a 95-item stress questionnaire; the results were analyzed statistically and used to select 74 items for the MSP. Group III (97 university students) Ss were given the 74-item MSP to determine the internal consistency of the instrument. Group IV (188 married couples with a primary school child) Ss were asked to answer the MSP for themselves and for their spouses. These results were analyzed statistically according to sex, family structure, and socioeconomic variables. Group V (66 adults aged 20–60 yrs) and Group VI (44 dental students) Ss were given a 53-item MSP on 2 to 4 occasions to evaluate test–retest and hypothetical-deductive validity. The results were evaluated using a multivariate analysis of variance (MANOVA). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
A. Weller and L. Weller (see record 1997-06365-004) claimed to report "the definitive study of menstrual synchrony" (p. 148). To allow for cycle variability, they used the following criterion for synchrony: It occurred in 2 out of 3 months. The underlying assumption of the state of menstrual synchrony is that cycle length variability is minimal. The present article uses a random selection of cycle lengths from a distribution described by R. F. Vollman (1977) to illustrate how variable cycle lengths cause a fluctuation from synchrony to asynchrony. A. Weller and L. Weller's study is not, therefore, conclusive, and future studies of menstrual synchrony should include an assessment of cycle variability as well as onset difference. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
46.
Social Adjustment and Politeness in Preschoolers 总被引:1,自引:0,他引:1
47.
Recorded heart rate in 9 male hooded rats and 1 male albino rat under conditions of satiation or food deprivation. Increased heart rate was associated with phasic movement or an erect posture. These 2 factors appeared to combine during face washing or licking of the back, resulting in heart rates up to 500/bpm. Food deprivation up to 47 hr. had no direct effect on heart rate. It is suggested that many of the results of studies relating heart rate in the rat to learning, motivation, arousal, etc. may be secondary effects of changed behavior patterns such as an increase or decrease in grooming. (French summary) (20 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Typical audible pedestrian signals indicate when the pedestrian walk interval is in effect but provide little, or even misleading information for directional alignment. In three experiments, blind and blindfolded sighted adults crossed a simulated crossing with recorded traffic noise to approximate street sounds. This was done to investigate how characteristics of signal presentation affected usefulness of the auditory signal for guiding crossing behaviour. Crossing was more accurate when signals came only from the far end of the crossing rather than the typical practice of presenting signals simultaneously from both ends. Alternating the signal between ends of the crossing was not helpful. Also, the customary practice of signalling two parallel crossings at the same time drew participants somewhat toward the opposite crossing. Providing a locator tone at the end of the crossing during the pedestrian clearance interval improved crossing accuracy. These findings provide a basis for designing audible pedestrian signals to enhance directional guidance. The principal findings were the same for blind and sighted participants and applied across a range of specific signals (e.g. chirps, clicks, voices). 相似文献
49.
Gustafson C Tretiak O Bertrand L Nissanov J 《Computer methods and programs in biomedicine》2004,74(1):53-61
Visualization software for three dimensional digital brain atlases present many challenges in design and implementation. These challenges include the design of an effective human interface, management of large data sets, display speed when slicing the data set for viewing/browsing, and the display of delineated volumes of interest (VOI). We present a software design, implementation and storage architecture that addresses these issues, allowing the user to navigate through a reconstructed volume quickly and smoothly, with an easy-to-use human interface. The software (macostat, for use with Macintosh OS) allows the user to rapidly display slices of the digital atlas at any arbitrary slicing angle, complete with delineated VOIs. The VOIs can be assigned colors of the user's choosing. The entire atlas, or selected portions, may be resliced with slices stored as individual image files, complete with delineations. These delineations may be transferred to corresponding sections of experimental materials using our analysis program (brain). The software may be obtained from the laboratory's web site: http://www.neuroterrain.org 相似文献
50.
Fibre-optic components fabricated on the same substrate as integrated circuits are important for future high-speed communications. One industry response has been the costly push to develop indium phosphide (InP) electronics. However, for fabrication simplicity, reliability and cost, gallium arsenide (GaAs) remains the established technology for integrated optoelectronics. Unfortunately, the GaAs bandgap wavelength (0.85 microm) is far too short for fibre optics at 1.3-1.5 microm. This has led to work on materials that have a large lattice mismatch on GaAs. Here we demonstrate the first light-emitting diode (LED) that emits at 1.5 microm fibre-optic wavelengths in GaAs using optical transitions from arsenic antisite (As(Ga)) deep levels. This is an enabling technology for fibre-optic components that are lattice-matched to GaAs integrated circuits. We present experimental results showing significant internal optical power (24 mW) and speed (in terahertz) from GaAs optical emitters using deep-level transitions. Finally, we present theory showing the ultimate limit to the efficiency-bandwidth product of semiconductor deep-level optical emitters. 相似文献