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111.
Kivlahan Daniel R.; Marlatt G. Alan; Fromme Kim; Coppel David B.; Williams Ellen 《Canadian Metallurgical Quarterly》1990,58(6):805
This study evaluated secondary prevention approaches for young adults (N?=?36, mean age 23 yrs) at risk for alcohol problems. Ss were randomly assigned to cognitive-behavioral alcohol skills training, a didactic alcohol information program, or assessment only. The skills program included training in blood alcohol level estimation, limit setting, and relapse prevention skills. All Ss maintained daily drinking records during the 8-wk intervention and for 1 wk at each follow-up. Repeated measures multivariate analysis of variance (MANOVA) found a significant reduction over 1-yr follow-up in self-reported alcohol consumption for the total sample. For all drinking measures, the directional findings consistently favored skills training. Despite overall reductions, most Ss continued to report occasional heavy drinking. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
112.
Sodium chlorite (SC) is an effective sanitizer for inhibiting microbial growth. This investigation was conducted to determine the efficacy of SC as a browning control agent for use on fresh-cut apple slices, applied alone, or in conjunction with organic acids. Additionally, the authors compared the efficacy of SC to that of acidified sodium chlorite (ASC) and to several other salts and examined the effect of pH and several different organic acids on efficacy of SC. The fresh-cut apple slices were dipped in treatment solutions for 1 min, then drained and placed in plastic containers at 20 °C for 24 h, and finally stored in polyethylene bags at 5 °C for 2 weeks. Color was measured periodically during storage. Lightness (L) values for all treated and control samples measured at 4 h, 24 h, and 2 weeks of storage were compared to L value for untreated samples measured immediately after cutting. Percent decrease in L-values was calculated for each sample at each time interval. Apple slices treated in ASC or SC solution had a significantly smaller decrease in L value indicating less browning than those treated in citric acid or water control at 4 h (P < 0.01), and with the exception of 1 g L−1 ASC and 0.1 g L−1 SC, all other ASC and SC treated slices still had significantly less browning than those for the water control (P < 0.01) at 24 h. After 2 weeks of storage, only SC (0.5–1.0 g L−1), sodium bisulfite (0.5 g L−1) and calcium l-ascorbate (10 g L−1) continued to inhibit browning. Treatment with 0.5 g L−1 SC and pH adjusted in the range from 3.9 to 6.2 using citric acid (CA) reduced browning more effectively than 0.5 g L−1 SC without pH adjustment. Two organic acids, salicylic acid and cinnamic acid, when added to SC solution, were found to achieve even better inhibition of browning than CA at the same pH value. 相似文献
113.
Eric A. Howe J. Ellen Marsden Therese M. Donovan Roland H. Lamberson 《Journal of Great Lakes research》2012
Sea lamprey (Petromyzon marinus) is a nuisance species in the Laurentian Great Lakes and Lake Champlain that has devastated native fish populations and hampered sport fisheries development. We developed a modified stage-based life history matrix for sea lamprey to analyze the effects of various management efforts to suppress sea lamprey population growth in Lake Champlain. These efforts targeted different life stages of the sea lamprey life cycle. A beta distribution was used to distribute stochastic larval populations among twenty sea lamprey-bearing tributaries and five deltas to Lake Champlain, from which sea lamprey that survive through larval metamorphosis were then pooled into a lake-wide parasitic-phase population. Parasitic-phase survival to the spawning stage was evaluated based on proximity to the natal tributary and on the size of the resident larval population in each tributary. Potential control strategies were modeled at egg to emergence, larval, and spawning stages to reduce vital rates at each stage, with the goal of suppressing parasitic-phase production. Simulations indicate that control of the larval stage was essential to achieving this goal, and with supplemental effort to reduce the vital rates at early life stages and at the spawning stage, the parasitic-phase population can be further suppressed. Sensitivity simulations indicate that the life history model was sensitive to egg deposition rate, abundance of parasitic-phase sea lamprey from unknown, uncontrolled sources, and the method in which parasitic-phase sea lamprey select tributaries for spawning. Results from this model can guide management agencies to optimize future management programs. 相似文献
114.
115.
The complexity of a social group may influence the vocal behavior of group members. Recent evidence in Carolina chickadees, Poecile carolinensis, indicated that one component of social complexity, group size, influenced the complexity of the "chick-a-dee" call, a vocalization functioning in social cohesion. Individuals in larger social groups used calls with greater information than did individuals in smaller social groups. Here, the authors review this earlier work, and describe a recent study indicating that social interactions between females and males within female-male pairs of chickadees were associated with rates of chick-a-dee call production in the males. Together, these studies suggest that the nature and complexity of social interactions among members of chickadee social groups influence chick-a-dee calling behavior. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
116.
Loraine Van Der Colff Ellen Podivinsky 《International Journal of Food Science & Technology》2008,43(12):2105-2112
The ability to detect GM material in otherwise unprocessed foods cooked using domestic methods is important should ‘ready‐to‐eat’ foods require labelling. This study addresses the issue of DNA degradation in foods as a result of cooking. A number of ‘domestic’ cooking methods were shown to affect the length of DNA sequences able to be PCR amplified from potato samples and the degree of degradation was treatment‐specific. However, a. real‐time PCR assay was developed and. GM material was positively identified in all cooked GM potato samples. This confirms that GM material should be able to be detected in otherwise unprocessed food samples cooked using domestic methods, even if the cooking process has partially degraded the DNA. Results indicate, however, that there may be implications of the cooking process on the ability to accurately quantify GM content in some cooked samples. 相似文献
117.
Janneke de Jonge Hans van Trijp Ellen Goddard Lynn Frewer 《Food quality and preference》2008,19(5):439-451
A thorough understanding of consumer confidence in the safety of food and the factors by which this is influenced is necessary for the development of adequate and effective risk management and communication regarding food safety issues. As food chains become globalized, risk management and communication are increasingly applied at international levels. As a consequence, cross-culturally valid theoretical models are needed to investigate consumer confidence in the safety of food. In this study, consumer confidence in the safety of food in Canada and the Netherlands was systematically compared. On the basis of two nationally representative samples, it was examined to what extent differences in consumer confidence between the two countries resulted from differences in the relative importance of the determinants of confidence, and differences in the means of the constructs. No differences between Canada and the Netherlands were found regarding the relative importance of the determinants, which provides support for the generalizability of the framework. However, results indicated that Dutch consumers had a higher level of optimism and a lower level of pessimism regarding the safety of food, which appeared to be mainly related to Dutch consumers’ lower level of concern about factors related to production. The results also indicated cross-national differences in consumer recall of food safety issues in the media. 相似文献
118.
Silver Ellen J.; Bauman Laurie J.; Coupey Susan M.; Doctors Shelley R.; Boeck Marjorie A. 《Canadian Metallurgical Quarterly》1990,59(2):305
To examine the effects of chronic illness on the psychological growth process known as ego development, scores were compared on the Sentence Completion Test for 36 teens (16 boys, 20 girls) with chronic illness and 50 teens (16 boys, 34 girls) without chronic illness. Their ages ranged from 13 to 21 years, with a mean of 17.4 years. Most were Black (37%) or Hispanic (41%) and lived in poor or working-class neighborhoods. When age, sex, and Peabody Picture Vocabulary Test (PPVT) scores were controlled in multiple regression analyses, no direct association between ego development stage and presence of chronic illness, severity of illness, age at onset, or duration of illness was found. Analysis of the chronically ill group alone revealed a significant PPVT?×?Severity interaction, indicating that ego development in chronically ill teens is lower when illness is more severe and verbal IQ is higher. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
119.
The durability of a commercially available injection molding grade polylactide (PLA) was assessed by exposure to conditions of elevated temperature and humidity over a period of several weeks. Moisture absorption, molecular weight, and mechanical performance were monitored over time and as a function of crystallinity level. At 50°C and 90% relative humidity, both amorphous and crystalline samples of PLA showed significant moisture absorption, allowing hydrolysis to occur. The study showed that while crystalline content had an effect on the initial moisture absorption behavior, the overall longer term effects on degradation were surprisingly minor. A cumulative damage model was used to relate the overall degradation due to moisture uptake and hydrolysis to long‐term durability in environments typical of automotive interiors. The study showed that the injection molding grade PLA resins that are currently commercially available are not suitable for use in applications that require long‐term durability in environments subject to elevated temperature and humidity. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010 相似文献
120.
在对连续加劲铝板屈曲和极限强度的敏感性研究基础之上,对压力作用下的铝板进行了深入研究。开发了一个经验公式,用于预测海洋工程中采用焊接加劲铝板在平面内轴压和各种侧向压力作用下的极限抗压强度。极限抗压强度的计算利用了一些的铝板敏感性分析的相关数据,推导出来的公式中含有两个参数,分别是板长细比和柱(加劲肋)长细比。推导过程中也用到了回归分析。公式考虑了焊接对初始缺陷和热影响区的影响。 相似文献