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991.
ABSTRACT: In order to understand the development of the microbial population within a hot-drinks vending machine a new machine was placed in a staff area of a university campus vending only hot chocolate. The machine was cleaned weekly using a detergent based protocol. Samples from the mixing bowl, dispense area, and drink were taken over a 19-wk period and enumerated using plate count agar. Bacillus cereus was identified using biochemical methods. Vended drinks were sampled at 0, 3, 6, and 9 min after vending; the hot chocolate powder was also sampled. Over the 1st 8 wk, a significant increase in the microbial load of the machine components was observed. By the end of the study, levels within the vended drink had also increased significantly. Inactivation of the automatic flush over a subsequent 5-wk period led to a statistically but not operationally significant increase in the microbial load of the dispense area and vended drink. The simple weekly clean had a significant impact on the microbial load of the machine components and the vended drink. This study demonstrated that a weekly, detergent-based cleaning protocol was sufficient to maintain the microbial population of the mixing bowl and dispense point in a quasi-steady state below 3.5 log CFU/cm2 ensuring that the microbial load of the vended drinks was maintained below 3.4 log CFU/mL. The microbial load of the drinks showed no significant changes over 9 min after vending, suggesting only spores are present in the final product. 相似文献
992.
Christian Kelly M.; Russ Sandra; Short Elizabeth J. 《Canadian Metallurgical Quarterly》2011,20(4):179
This study investigated the effect of anxiety on play processes in 43 first-, second-, and third-grade children. Using a mood-induction procedure, this study compared processes in play among children randomized to an anxious or neutral mood-induction procedure. Children were assessed using the Affect in Play Scale pre- and post-mood-induction. In addition, this study examined relationships between pretend play processes and self-reported state and trait anxiety levels using the State Trait Anxiety Inventory for Children. Findings demonstrated a significant negative relationship between baseline state anxiety level and organization of the play narrative. Consistent with previous research, children in both conditions significantly improved on multiple play scores over time. Although pretend play processes were not significantly affected by condition assignment, further analysis with a more sensitive measure of affect in play revealed a significant interaction between state anxiety and condition assignment on the amount of positive affect expressed in play. Results indicate that play processes can improve with time and greater state anxiety may impact organization and affective processes in play. Implications for play therapy are discussed in terms of the potential impact anxiety has on play processes. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
993.
Jeff Deshon Dennis Hussey Brian Kendrick John McGurk Jeff Secker Michael Short 《JOM Journal of the Minerals, Metals and Materials Society》2011,63(8):64-72
Pressurized water reactors circulate high-temperature water that slowly corrodes Inconel and stainless steel system surfaces,
and the nickel/iron based corrosion products deposit in regions of the fuel where sub-cooled nucleate boiling occurs. The
deposited corrosion products, called ‘crud’, can have an adverse impact on fuel performance. Boron can concentrate within
the crud in the boiling regions of the fuel leading to a phenomenon known as axial offset anomaly (AOA). In rare cases, fuel
clad integrity can be compromised because of crud-induced localized corrosion (CILC) of the zirconium-based alloy. Westinghouse
and the Electric Power Research Institute have committed to understanding the crud transport process and develop a risk assessment
software tool called boron-induced offset anomaly (BOA) to avoid AOA and CILC. This paper reviews the history of the BOA model
development and new efforts to develop a micro-scale model called MAMBA for use in the Consortium for Advanced Light Water
Reactor Simulation (CASL) program. 相似文献
994.
One of the impediments to large-scale use of wind generation within power systems is its nondispatchability and variable and uncertain real-time availability. Operating constraints on conventional generators such as minimum generation points, forbidden zones, and ramping limits as well as system constraints such as power flow limits and ancillary service requirements may force a system operator to curtail wind generation in order to ensure feasibility. Furthermore, the pattern of wind availability and electricity demand may not allow wind generation to be fully utilized in all hours. One solution to these issues, which could reduce these inflexibilities, is the use of real-time pricing (RTP) tariffs which can both smooth-out the diurnal load pattern in order to reduce the impact of binding unit operating and system constraints on wind utilization, and allow demand to increase in response to the availability of costless wind generation. We use and analyze a detailed unit commitment model of the Texas power system with different estimates of demand elasticities to demonstrate the potential increases in wind generation from implementing RTP. 相似文献
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F Pages TA Flam A Vieillefond V Molinie X Abeille V Lazar B Bressac-de Paillerets V Mosseri M Zerbib WH Fridman B Debré N Thiounn 《Canadian Metallurgical Quarterly》1998,159(3):1079-1084
PURPOSE: In superficial urothelial tumors of the bladder, p53 status is currently the most informative pretreatment parameter to define a population at higher risk for invasive carcinoma. Also, in T1 tumors, occurrence of muscular invasion is often related to an early relapse following BCG therapy. With the knowledge of biological parameters able to identify the group of initial BCG therapy non-responders, it would be possible to offer earlier treatment to the patients who need a more aggressive mode of therapy. The aim of this work was to study the predictive value of the p53 tumor status on the early BCG therapy response. MATERIALS AND METHODS: The population included a selected group of 43 patients presenting T1 bladder tumors with no carcinoma in situ (Tis), treated by transurethral resection (TUR) followed by intravesical BCG therapy. Clinical outcome was analyzed in relation to usual clinical and histopathological parameters, and pretreatment p53 tumor status was assayed by an immunohistochemical technique using DO7 monoclonal antibody. For 16 specimens, p53 gene was investigated using a Single Strand Conformation Polymorphism (SSCP) analysis and sequence determination. RESULTS: p53 anomalies were strongly correlated to smoking behavior (p = 0.003) and tumoral grade (p = 0.025). Univariate analysis revealed an absence of correlation between p53 immunostaining and initial, one and two years response-rate to BCG therapy. However, longterm followup revealed a trend between positive staining and disease progression. The p53 molecular study validated the use of DO7 immunostaining in detection of p53 anomalies. CONCLUSIONS: In T1 bladder tumors, pretreatment p53 determination was not useful to define a group of early BCG non-responders. Thus, p53 status and immunological response induced by BCG endovesical therapy are two independent events. 相似文献