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51.
The development of a community of lactic acid bacteria from vacuum-packaged beef was investigated during a 6-week storage trial at 2 degrees C. The lactic acid bacteria population was monitored by using molecular techniques to identify a random sample of isolates at biweekly intervals during the storage trial. The polymerase chain reaction and a randomly amplified polymorphic DNA technique were used to identify and distinguish populations of lactic acid bacteria that developed during the storage trial. At week 0, the population of lactic acid bacteria was 3.5 log cfu/120 cm2 and by week 6, the population reached a maximum of 7.6 log cfu/120 cm2. A sampling from the week 0 population indicated a mixed community of Lactobacillus curvatus, Lactobacillus sakei and Leuconostoc spp. However, the sampling from week 6 indicated the population composition had changed to one where a single Leuconostoc strain predominated. This strain demonstrated antagonism towards the growth of other lactic acid bacteria isolated during the study. Additionally, the strain inhibited the growth of foodborne pathogens Escherichia coli O157:H7 and Listeria monocytogenes. DNA sequence data from the 16S rRNA gene suggested that the isolate may be a Leuconostoc gelidum strain. 相似文献
52.
Common domestic solar water heating system usage patterns were investigated by a survey of 55 installations. These usage patterns
were modelled by simulation based on the actual occupants' use of boiler or other auxiliary heating control strategies. These
strategies were not optimal, as often assumed. The effectiveness of the technology was found to be highly sensitive to the
time settings used for auxiliary water heating, and the 65% of solar householders using their boilers in the mornings were
found to be forgoing 75% of their potential savings. Additionally, 92% of consumers were found to be small households, whose
potential savings were only 23% of those of larger households, which use more hot water. Overall the majority (at least 60%)
of the systems surveyed were found to be achieving no more than 6% of their potential savings. Incorporating consideration
of Legionella issues, results indicate that if solar thermal technology is to deliver its potential to CO2 reduction targets: solar householders must avoid any use of their auxiliary water heating systems before the end of the main
warmth of the day, grants for solar technology should be focused on households with higher hot water demands, and particularly
on those that are dependent on electricity for water heating, health and safety requirements for hot water storage must be
reviewed and, if possible, required temperatures should be set at a lower level, so that carbon savings from solar water heating
may be optimized. 相似文献
53.
Frances Heywood 《Housing Studies》1997,12(1):27-46
As private home ownership grows in Europe, so do the problems of maintenance and repair for poorer owners. In England, it has been believed that one obstacle is the owners' apparent satisfaction with poor conditions. This paper deconstructs the questions in the English House Condition Survey 1981 on which that assumption has been based. By reference to other EHCSs and to a research methodology offering a more differentiated approach to establishing residents' views, it suggests that the problem is not ignorance at all. A more subtle understanding of the validity of housing satisfaction questionnaires is needed to develop effective policies of urban renewal. 相似文献
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Kemenoff Sylvia; Worchel Frances; Prevatt Bruce; Willson Victor 《Canadian Metallurgical Quarterly》1995,9(4):446
The authors compared the effectiveness of video feedback to verbal feedback within the context of Milan Systemic family therapy. Ten families were randomly assigned to either the video- or verbal-feedback condition, resulting in 16 participants in each condition. Families engaged in 5 wks of family therapy, which included either verbal or video feedback on a family interaction task. Changes from pretreatment to posttreatment were analyzed for several problem-related and family variables. Results indicated significant pretreatment posttreatment (controlling for family) interactions for responsibility for the problem and family adaptability. Support was found for the therapeutic effects of video feedback within Milan Systemic therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
58.
S Lagrange O Chosidow JC Piette B Wechsler P Godeau C Frances 《Canadian Metallurgical Quarterly》1997,6(6):514-520
This article continues the series of electronic microscopical investigations of tick attachment and host's inflammatory reaction in the attachment site. In all this works we used larvae of different Ixodid ticks but the same species of the host (white mouse), Ixodid species having different type of attachment. Dermacentor marginatus (Amosova, 1989a) is characterized by the superficial penetration of mouth parts, the abundance of cement around them and on the surface of the host's skin, the mouth parts of Hyalomma asiaticum are fully inserted and the superficial cement is minimal (Amosova, 1989b) and Ixodes ricinus has mouth parts inserted more deeply in the skin tissue of the host and the cement substance localised only on the surface of the skin at the 1st and 2nd days of feeding period. For this investigation we choose Haemaphysalis longicornis because it is known (see Kemp et al., 1982) that genus Haemaphysalis has the most superficial localisation of the mouth parts in the attachment site. We have studied a fine structure of cement cone and the cement substance surrounding the mouth parts in the skin and have demonstrated that it is very similar to the Dermacentor marginatus cement structure. The pattern of cellular response is similar to D. marginatus lesion too. 相似文献
59.
Navigation in humans and many other animals relies on spatial representations of their environments. Three experiments examined how humans maintain sense of orientation between nested environments. Subjects can acquire new spatial representations easily without integrating them into their existing spatial knowledge system. While navigating between nested environments, subjects seemed to constantly switch between the currently processed environment by reorienting to approaching environments and losing track of old environments at given spatial regions. These results suggest that spatial updating in naturalistic, nested environments does not occur for all environments at the same time. Implications for the hierarchical theory of spatial representations and the path integration theory of navigation are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
60.
Frances Jrgensen Bjrge Timenes Laugen Harry Boer 《Creativity & Innovation Management》2007,16(4):363-375
This paper investigates the relationship between HRM practices and Continuous Improvement (CI) activities in order to gain an understanding of how the HRM function may be utilized to improve CI implementation success, and consequently, company performance. The paper begins with a brief review of the HRM and CI literature and then presents statistical analyses of data collected from the Continuous Improvement Network Survey (2003), which demonstrate that HRM has a significant effect on CI behaviour and company performance, with the strongest relationship between HRM, CI and performance occurring when companies align their CI activities with their strategic objectives and use systems, procedures and processes to measure the results of their CI activities. 相似文献