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41.
The intertidal pulmonate limpetTrimusculus reticulatus, which is found in caves or crevices along the California coast, was previously reported to contain two novel diterpenoids, 6-isovaleroxylabda-8,13-dien-7,15-diol (1) and 2,7-diacetoxy-6-isovaleroxylabda-8,13-dien-15-ol (2). Dissection of the animals prior to extraction revealed that the diterpenoids were concentrated in the mantle, foot, and mucus, but not in the viscera. The presence ofT. reticulatus or its mucus was toxic to veliger larvae of the sabellariid reef-building tube wormPhragmatopoma californica. The major diterpenoid1 was responsible for the observed larvicidal activity. Protection against overgrowth by settling invertebrate larvae is important for the survival of this sessile filter-feeding pulmonate. A related pulmonate,T. conica, which was found in similar intertidal habitats in New Zealand, contained 6-acetoxy-7-isovaleroxylabda-8,13-dien-15-oic acid (3) and 1,7,12,18-tetraacetoxy-cholest-5-en-3-ol (4). The diterpene3 was also localized in the foot, mantle, and mucus ofT. conica but was not larvicidal toP. californica. 相似文献
42.
The U.S. Food Safety and Inspection Service (FSIS) pathogen reduction-hazard analysis critical control point systems final rule, published in 1996, established Salmonella performance standards for broiler chicken, cow and bull, market hog, and steer and heifer carcasses and for ground beef, chicken, and turkey meat. In 1998, the FSIS began testing to verify that establishments are meeting performance standards. Samples are collected in sets in which the number of samples is defined but varies according to product class. A sample set fails when the number of positive Salmonella samples exceeds the maximum number of positive samples allowed under the performance standard. Salmonella sample sets collected at 1,584 establishments from 1998 through 2003 were examined to identify factors associated with failure of one or more sets. Overall, 1,282 (80.9%) of establishments never had failed sets. In establishments that did experience set failure(s), generally the failed sets were collected early in the establishment testing history, with the exception of broiler establishments where failure(s) occurred both early and late in the course of testing. Small establishments were more likely to have experienced a set failure than were large or very small establishments, and broiler establishments were more likely to have failed than were ground beef, market hog, or steer-heifer establishments. Agency response to failed Salmonella sample sets in the form of in-depth verification reviews and related establishment-initiated corrective actions have likely contributed to declines in the number of establishments that failed sets. A focus on food safety measures in small establishments and broiler processing establishments should further reduce the number of sample sets that fail to meet the Salmonella performance standard. 相似文献
43.
Characterization and corrosion protection properties of polypyrrole / montmorillonite electropolymerized onto aluminium alloy 1100 总被引:1,自引:1,他引:0
Kátia R. L. Castagno Viviane Dalmoro Raquel S. Mauler Denise S. Azambuja 《Journal of Polymer Research》2010,17(5):647-655
Films of Polypyrrole/Montmorillonite (PPy/MT) clays were electropolymerized potentiostatically on aluminium alloy 1100, using
sodium dodecylbenzenesulfonate (SDBS) as a dopant. Two clay species were used: Na+-Montmorillonite (MT-Na) and modified-Montmorillonite (MT-M). The characterization of the PPy/MT films performed by XRD and
TEM shows that the exfoliation method employed, as well the electrochemical polymerization method used in this work, allow
nanocomposite materials to be obtained. The PPy/MT films were found to have less electrical conductivity than pure PPy. The
corrosion protection of aluminium alloy 1100 covering PPy/MT was evaluated by electrochemical techniques in 0.05 mol L−1 NaCl medium. The electrochemical parameters derived from the polarization curves, together with the EIS data, revealed that
the corrosion resistance of PPy/clay coatings depends on the type and concentration of Montmorillonite employed. The best
performance in the corrosion protection of the aluminum was achieved with PPy/MT films containing 1% of clay. 相似文献
44.
Forman Susan G.; Fagley N. S.; Steiner Denise Dreitlein; Schneider Kenneth 《Canadian Metallurgical Quarterly》2009,3(4):226
This study examined perceptions of school psychologists regarding their use of evidence-based interventions in school settings after completing a graduate course in school-based psychosocial interventions. Ninety-four individuals who completed the course during the 10 years prior to the study were asked to complete a survey that focused on personal and organizational factors affecting the implementation of evidence-based interventions through assessment of (a) the extent of their use of interventions in professional school psychology practice, (b) perceptions of facilitators to implementation, and (c) perceptions of barriers to implementation. Fifty-four responded (a 57% response rate); analyses were conducted on the responses of 34 individuals who indicated that they were currently school psychologists working in schools. Results indicated that school psychologists’ personal beliefs about the interventions influenced their decisions to implement them. Several evidence-based interventions were less likely to be used in urban practice settings. Training in evidence-based interventions should address the personal and contextual issues that are related to implementation, as well as the procedures of the interventions. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
45.
46.
To understand how mammalian herbivores process plant secondary compounds, we examined differences in expression of biotransformation enzyme mRNAs among populations of wild woodrats (Neotoma lepida) and laboratory rats. We compared expression of mRNAs for 10 biotransforming enzymes in five families (CYP, mEH, QOR, GST, and UGT) by using Northern blot analysis. We found significant differences in eight of 10 mRNAs tested. We suggest that the differences in mRNA expression among populations of woodrats and laboratory rats may be due to differences in the secondary compound composition of their diets. Our results provide background for future studies of detoxification strategies in mammalian herbivores that combine pharmacological techniques with an ecological perspective. 相似文献
47.
Bike Denise H.; Norcross John C.; Schatz Danielle M. 《Canadian Metallurgical Quarterly》2009,46(1):19
In this replication and extension of a national survey of psychotherapists conducted in 1987, American psychologists (n = 219), counselors (n = 191), and social workers (n = 192) reported in 2007 on the processes and outcomes of their personal therapy experiences. Of the 85% who sought therapy at least once, women, men, and members of all three professions were equally as likely to have received personal treatment. Their top reasons for seeking therapy were marital–couple distress (20%), depression (13%), need for self-understanding (12%), and anxiety–stress (10%). Approximately 24% used psychotropic medication in combination with personal therapy. More than 90% of therapists reported positive outcomes across multiple domains. The modal lasting lessons from personal treatment related to therapist reliability, skill, and empathy. The results are tentatively compared with those obtained in 1987, thus chronicling the evolution of personal therapy among psychologists and social workers during the past 20 years. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
48.
Detoxification in Relation to Toxin Tolerance in Desert Woodrats Eating Creosote Bush 总被引:1,自引:0,他引:1
Antonio M. Mangione Denise Dearing William Karasov 《Journal of chemical ecology》2001,27(12):2559-2578
We studied the relationship between the use of three detoxification pathways and urine pH and the tolerance of desert woodrats from two populations to a mixture of naturally occurring plant secondary metabolites (mostly phenolics) in resin from creosote bush (Larrea tridentata). The two populations of desert woodrats came from the Mojave desert (Mojave woodrats), where woodrats consume creosote bush, and from the Great Basin desert (Great Basin woodrats), where the plant species is absent. We fed woodrats alfalfa pellets containing increasing levels of the phenolic resin and measured three detoxification pathways and urine pH that are related to detoxification of allelochemicals. We found that the excretion rate of two phase II detoxification conjugates, glucuronides and sulfides, increased with increasing resin intake, whereas excretion of hippuric acid was independent of resin intake, although it differed between populations. Urine pH declined with increasing resin ingestion. The molar proportion of glucuronides in urine was three times that of the other conjugates combined. Based on an evaluation of variation in the three detoxification pathways and urine pH in relation to resin intake, we rejected the hypotheses that woodrats' tolerance to resin intake is related to capacity for amination, sulfation, or pH regulation. However, Mojave woodrats had higher maximum glucuronide excretion rates, and we accepted the hypothesis that within and between populations woodrats tolerate more resin because they have a greater capacity for glucuronide excretion. 相似文献
49.
Héctor A. Ruiz Denise S. Ruzene Daniel P. Silva Mafalda A.C. Quintas António A. Vicente José A. Teixeira 《Journal of chemical technology and biotechnology (Oxford, Oxfordshire : 1986)》2011,86(1):88-94
BACKGROUND: Hydrothermal processes are an eco‐friendly processes that provide an interesting alternative for chemical utilization of lignocellulosic materials, in which water and crop residues are the only reagents. In this work the effect of process conditions (size distribution of the wheat straw, temperature and time) was evaluated against production of fermentable products. RESULTS: The use of milled wheat straw fractions as a raw material containing blends of different particle size distribution showed that the latter had an influence on the final sugars in the hydrolysate. Improved values of glucose (21.1%) and xylose yields (49.32%) present in the hydrolysate were obtained with treatment severity factors of 2.77 and 3.36, respectively. Mathematical models were developed aimed at establishing the effect of process conditions on monosaccharide concentration and its degradation in the liquor. CONCLUSION: This work shows that the use of wheat straw blends with various particle sizes has a significant effect on the extraction of fermentable products. The effect of treatment severity, which takes into account both processing time and temperature was also evaluated. These results are of importance for process design. Copyright © 2010 Society of Chemical Industry 相似文献
50.