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241.
Soudjouk-style batter was inoculated with a five-strain mixture of Escherichia coli O157:H7 at about 7.6 log10 CFU/g in each of two trials. The sticks were fermented and dried at 22 degrees C and 50% relative humidity (RH) for 3 days and then at 9 degrees C and 40% RH for 18 h. After being flattened to about 1.25 cm, the sticks were conditioned at 38 degrees C and 70% RH or at 22 degrees C and 50% RH for about 3 days. After the latter conditioning treatment, sticks either were cooked to an internal temperature of 63 degrees C or received no heat treatment. Final mean pH values after conditioning at 22 degrees C and 50% RH for soudjouk manufactured with a starter culture and dextrose (1.0%) and for soudjouk manufactured without a starter culture were about 4.9 and 6.0, respectively. For soudjouk produced with a starter culture, pathogen numbers were reduced by 4.53 and 0.88 log10 CFU/g after conditioning at 38 degrees C and 70% RH and at 22 degrees C and 50% RH, respectively. For soudjouk produced via natural fermentation, pathogen numbers were reduced by 1.39 and 0.09 log10 CFU/g after conditioning at 38 degrees C and 70% RH and at 22 degrees C and 50% RH, respectively. Cooking reduced pathogen numbers to below the levels detectable by direct plating (<1.0 log10 CFU/g) and by enrichment for soudjouk produced with a starter culture and also reduced pathogen numbers by 6.28 log10 CFU/g for soudjouk produced via natural fermentation. However, cooking also resulted in an unacceptable product. In general, the reduction in pathogen numbers achieved by storage at ambient temperature (25 degrees C) was greater than that achieved by storage at cooler temperatures (4 and 15 degrees C), particularly for soudjouk prepared with a starter culture (for which a final pH value of 4.8 and a 6.4-log10 reduction were obtained after 21 days at 25 degrees C) rather than for that prepared without a starter culture (for which a final pH value of 6.1 and a 2.6-log10 reduction were obtained after 21 days at 25 degrees C). These results indicate that naturally fermented old-country-type sausage may allow the survival of E. coli O157:H7 in the absence of controlled fermentation, postfermentation cooking, and/or an ambient-storage processing step.  相似文献   
242.
Little is known about how emulsion characteristics affect saltiness/bitterness perception. Sensory detection and recognition thresholds of NaCl, caffeine, and KCl in aqueous solution compared with oil‐in‐water emulsion systems were evaluated. For emulsions, NaCl, KCl, or caffeine were dissolved in water + emulsifier and mixed with canola oil (20% by weight). Two emulsions were prepared: emulsion 1 (viscosity = 257 cP) and emulsion 2 (viscosity = 59 cP). The forced‐choice ascending concentration series method of limits (ASTM E‐679‐04) was used to determine detection and/or recognition thresholds at 25 °C. Group best estimate threshold (GBET) geometric means were expressed as g/100 mL. Comparing NaCl with KCl, there were no significant differences in detection GBET values for all systems (0.0197 ‐ 0.0354). For saltiness recognition thresholds, KCl GBET values were higher compared with NaCl GBET (0.0822 ‐ 0.1070 compared with 0.0471 ‐ 0.0501). For NaCl and KCl, emulsion 1 and/or emulsion 2 did not significantly affect the saltiness recognition threshold compared with that of the aqueous solution. However, the bitterness recognition thresholds of caffeine and KCl in solution were significantly lower than in the emulsions (0.0242 ‐ 0.0586 compared with 0.0754 ‐ 0.1025). Gender generally had a marginal effect on threshold values. This study showed that, compared with the aqueous solutions, emulsions did not significantly affect the saltiness recognition threshold of NaCl and KCl, but exhibited bitterness‐suppressing effects on KCl and/or caffeine.  相似文献   
243.
Obtaining spirometric testing and providing those results to individuals who smoke has been advocated as a motivational tool to improve smoking cessation. However, its effectiveness is not known. We conducted a systematic review to determine if this approach improves rates of smoking cessation. Data sources included MEDLINE (1966 to October 2005), the Cochrane Library, and experts in the field. Eligible randomized controlled trials (RCTs) enrolled at least 25 smokers per arm, evaluated spirometry with associated counseling or in combination with other treatments, followed subjects at least 6 months, and provided smoking abstinence rates. Results from nonrandomized studies also were summarized. The primary outcome was patient-reported long-term (at least 6 months) sustained abstinence with biological validation. Additional outcomes included self-reported abstinence and point-prevalence abstinence. Seven RCTs (N = 6,052 subjects) met eligibility criteria. Follow-up duration ranged from 9 to 36 months. In six trials, the intervention group received concomitant treatments previously demonstrated to increase cessation independently. The range of abstinence was 3%-14% for control subjects and 7%-39% among intervention groups, statistically significantly in favor of intervention in four studies. The only RCT that assessed the independent contribution of spirometry in combination with counseling demonstrated a nonsignificant 1% improvement in patient-reported point-prevalence abstinence at 12 months in the group that received spirometry plus counseling versus counseling alone (6.5% versus 5.5%). Findings from observational studies were mixed, and the lack of controls makes interpretation problematic. Available evidence is insufficient to determine whether obtaining spirometric values and providing that information to patients improves smoking cessation compared with other smoking cessation methods. Spirometric values are of limited benefit as a predictor of smoking cessation or as a tool to "customize" smoking cessation strategies.  相似文献   
244.
Objective: Negative affect is a significant predictor of alcohol relapse, and the relation between negative affect and drinking has been shown to be strongly mediated by alcohol craving. Thus, targeting craving during treatment could potentially attenuate the relation between negative affect and drinking. Method: The current study is a secondary analysis of data from the COMBINE study, a randomized clinical trial that combined pharmacotherapy with behavioral intervention in the treatment of alcohol dependence. Our goal in the current study was to examine whether a treatment module that targeted craving would predict changes in negative mood during the 16-week combined behavioral intervention (n = 776) and the relation among changes in mood, craving, and changes in heavy drinking during treatment and 1 year posttreatment. Results: Changes in negative mood were significantly associated with changes in heavy drinking during treatment (f2 = 0.78). Participants (n = 432) who received the craving module had significantly fewer heavy drinking days during treatment (d = 0.31), and receiving the module moderated the relation between negative mood and heavy drinking during treatment (f2 = 0.92) and 1 year posttreatment (f2 = 0.03). Moderating effects of the craving module were mediated by changes in craving during treatment. Within-subject analyses indicated significant pre- to postmodule reductions in negative mood. Additionally, postmodule craving significantly mediated the association between negative mood and heavy drinking during treatment and at posttreatment. Conclusions: The craving module of the combined behavioral intervention may weaken the relation between negative affect and heavy drinking by fostering greater decreases in craving during treatment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
245.
246.
A commercially available, sintered silicon carbide was exposed to a temperature of 982°C for up to 50 h in a burner rig pressurized to 500 kPa. Synthetic sea salt added to the flame (5 ppm) resulted in the deposition of sodium sulfate and formation of a sodium magnesium silicate corrosion product. A 16% reduction in room-temperature strength occurred after 5 h of exposure; this reduction was due to the formation of surface pits. Exposure for longer times resulted in continued strength reduction, up to 56% at 25 h. Samples exposed for 50 h were so degraded that mechanical tests could not be conducted. The strength after 25 h of exposure to a salt concentration of 2 ppm was similar to the as-received strength, whereas exposures to 10 ppm of salt resulted in strengths similar to that observed with 5 ppm of salt.  相似文献   
247.
Although drug users' self-report has provided data for much of the published literature about drug use, little is known about self-report validity when participants are asked about diseases that are associated with drug abuse, such as hepatitis. Injecting drug users and crack cocaine smokers (N?=?669) were recruited in Anchorage, Alaska, and asked whether they had been diagnosed previously with hepatitis B. These self-report data were compared to various hepatitis B and C seromarkers as measures of validity of self-report expressed as sensitivity and specificity. Results indicate that although test-retest reliability for self-report is high (.905) and specificity is high (96.06% for hepatitis C virus, or HCV), sensitivity is low (23.74% for HCV). Thus, because of its low sensitivity, self-report of hepatitis should be used only as a prevalence estimate lower bound. More than half of the drug users who had contracted hepatitis had never been told that they were infected. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
248.
This paper proposes a procedure for identifying the inertia matrix of a rotating body. The procedure based on Euler's equation governing rotational motion assumes errors‐in‐variables models in which all measurements, torque as well as angular velocities, are corrupted by noises. In order for consistent estimation, we introduce an extended linear regression model by augmenting the regressors with constants and the parameters with noise‐contributed terms. A transformation, based on low‐pass filtering, of the extended model cancels out angular acceleration terms in the regressors. Applying the method of least correlation to the model identifies the elements of the inertia matrix. Analysis shows that the estimates converge to the true parameters as the number of samples increases to infinity. Monte Carlo simulations demonstrate the performance of the algorithm and support the analytical consistency. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   
249.
A numerical model was developed to simulate the micro-deformations of a polymeric substrate due to lithographic processing of different layers of a transistor-like structure. The results of the model were validated with the results from experiments. The model, a mechanical-thermal-hygroscopic model, takes into account the dimensional effects of temperature, moisture and stresses. It also includes the temperature dependent visco-elastic behaviour of the polymer substrate. The model can be used to predict overlay accuracies between different functional layers introduced by the lithographic process. It can also be used to understand the underlying processes such that it provides a tool to improve the overlay accuracy during actual processing.  相似文献   
250.
The gene coding for the brain derived neurotrophic factor (BDNF) has emerged as an interesting candidate for multiple brain and brain disorder-related phenomena. The primary aim of the present investigation was to consider the relationship between the BDNF Val66Met variant and two phenotypes: compulsive hoarding as a symptom dimension of obsessive–compulsive disorder (OCD), and body mass index (BMI). We examined the BDNF gene in a large (N = 301) clinical sample of probands with OCD. Participants were classified as hoarding or nonhoarding using a strict, multimeasure grouping approach. Results revealed that the Val/Val genotype was linked with hoarding classification and more severe hoarding behaviors, as well as greater BMI levels. Hoarding status was also associated with greater BMI scores, with individuals in the hoarding group being far more likely to be classified as obese compared with the nonhoarding group. Our findings may provide a distinct avenue through which hoarding and BMI could be linked. These findings are suggestive of a complex gene, body weight, and psychopathology relationship wherein a primitive, survival “thrifty gene” strategy may be conserved and represented in a subgroup of humans manifesting severe hoarding symptoms. (PsycINFO Database Record (c) 2011 APA, all rights reserved)  相似文献   
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