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41.
This study of selected jobs in the health care sector explored a range of physical and psychosocial factors to identify those that most strongly predicted work-related musculoskeletal disorders (WMSD) risk. A self-report survey was used to collect data on physical and psychosocial risk factors from employees in three health care organisations in Victoria, Australia. Multivariate analyses demonstrated the importance of both psychosocial and physical hazards in predicting WMSD risk and provides evidence for risk management of WMSDs to incorporate a more comprehensive and integrated approach. Use of a risk management toolkit is recommended to address WMSD risk in the workplace. 相似文献
42.
S. Rod Jenkins James B. Pocock Patrick D. Zuraski Ronald B. Meade Zane W. Mitchell Jodi J. Farrington 《Canadian Metallurgical Quarterly》2002,128(2):75-82
The Dept. of Civil and Environmental Engineering at the United States Air Force Academy has developed a capstone senior level integration experience that blends technical aspects of an engineering design with construction and realistic issues of modern society. Technical designs accomplished by the students, prior to taking the capstone course, form the technical basis of the capstone design experience. The students review the technical design and prepare the project for construction through incorporating engineering standards and considering realistic issues. Issues considered include economy, constructability, and environmental aspects, as well as ethical, health and safety constraints. The students prepare a final design report and make an oral presentation to an interdisciplinary panel of engineering faculty. This capstone course is the culmination of a total integration experience, which includes a hands-on field engineering course, and two years of a rigorous engineering design curriculum. 相似文献
43.
A qualitative study consisting of in-depth interviews with 17 play therapists was undertaken to identify how play therapists understand children. Analysis of the interviews illuminated how play therapists need to "fill in the blanks" in the stories of children through a frame of reference that constructed children and childhood relative to children's experiences with abuse and neglect. Recommendations are made for supplementary education, supervision and consultation for professionals meeting the needs of children. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
44.
Cucumber seedlings were grown in 5 mM MES [2-(N-morpholino)ethanesulfonic acid] -buffered nutrient solutions adjusted to a pH of 5.5, 6.25, or 7.0. Nutrient solutions were changed on alternate days. Seedlings were treated for a two-day period with various concentrations (0–1 mM) of ferulic acid,p-coumaric acid, or mixtures of these phenolic acids when 16 days old. Leaf growth, dry weight, and water utilization of the seedlings; pH of the solutions; and disappearance of the phenolic acids from nutrient solutions were monitored. Leaf area expansion of cucumber seedlings was inhibited by both ferulic andp-coumaric acid, and the magnitude of these inhibitions was influenced by concentration and pH. Inhibition of leaf area expansion was greater at pH 5.5 and nominal at pH 7.O. Ferulic acid was more inhibitory thanp-coumaric acid. The effect of pH on growth was best described by data for mean relative rates of leaf expansion. For example, the mean relative rates of leaf expansion by both acids at 0.5 mM for the 16- to 18-day growth period (treatment period) were reduced by 45, 31, and 8% for the pH 5.5, 6.25, and 7.0 treatments, respectively. The dry weight of seedlings at harvest (day 22) was significantly reduced for seedlings grown in the pH 5.5 and 6.25 treatments, but not for the pH 7.0 treatment. There was, however, one exception; the dry weight of seedlings treated withp-coumaric acid solutions adjusted to a pH of 5.5 was not significantly reduced. Water utilization by the seedlings was reduced by both ferulic andp-coumaric acid. Again, the impact of ferulic acid was greater thanp-coumaric acid. The effect of ferulic acid on water utlization decreased with increasing pH of the nutrient solution. The pH effects were not so consistent forp-coumaric acid. The effects of equimolar mixtures of the two phenolic acids were additive for all variables measured. There was a linear correlation between mean relative rates of leaf expansion and water utilization.Paper No. 9693 of the Journal Series of the North Carolina Agricultural Research Sevice, Raleigh, North Carolina. Mention of a trademark or a propriety product does not constitute a guarantee or warranty of the product by the Agricultural Research Service and does not imply its approval to the exclusion of other products that may be suitable. 相似文献
45.
Cucumber seedlings (Cucumis sativus cv. Early Green Cluster) ranging from 6 to 16 days of age were treated with various concentrations (0– 1 mM) of caffeic, ferulic,p-coumaric,p-hydroxybenzoic, protocatechuic, sinapic, syringic, and vanillic acids and mixtures of ferulic acid and one or two of the other phenolic acids. Seedlings were grown in full-strength Hoagland's solution which was changed every other day. Phenolic acid treatments were given with each nutrient solution change starting at day 6 or given once when seedlings were 13 or 14 days old. Leaf area, mean relative rates of leaf expansion, transpiration rates, water utilization, and the concentrations of the phenolic acids in nutrient solution were determined at one- or two-day intervals. Seedling dry weight was determined at final harvest. Seedling leaf area and dry weight were linearly related. Since leaf areas can be easily obtained without destructive sampling and leaf area expansion responds rapidly to phenolic acid treatments, it was utilized as the primary indicator of plant response. The resulting data suggested that a number of ferulic acid microbial metabolic products, as well as two other phenolic acids observed in soils (p-coumaric and syringic acid), can reduce seedling dry weight, leaf expansion, and water utilization of cucumber seedlings in a similar manner. The magnitude of impact of each of the phenolic acids, however, varied with phenolic acid and concentration. It appears that the inhibitory activity of these phenolic acids involved water relations of cucumber seedlings, since the phenolic acid treatments resulted in closure of stomata which then remained closed for several days after treatment. The data also demonstrated that the effects of mixtures of phenolic acids on cucumber seedlings may be synergistic, additive, or antagonistic. The type of response observed appeared to be related to the factor measured, the compounds in the nmixture, and the magnitued of inhibition associated with each compounds. The data also indicated that the effects of the various phenolic acids were reversible, since seedling leaf area increased rapidly once phenolic acids were removed from the root environment. Mean relative rates of leaf expansion recovered even in the presence of the various phenolic acids.Paper No. 9396 of the Journal Series of the North Carolina Agricultural Research Service. Raleigh, North Carolina. Mention of a trademark or proprietary product does not constitute a guarantee or warranty of the product by the Agricultural Research Service and does not imply its approval to the exclusion of other products that may be suitable. 相似文献
46.
Johanna Reske Jodi Siebrecht Jan Hazebroek 《Journal of the American Oil Chemists' Society》1997,74(8):989-998
Changes in composition were examined in oils extracted from genetically modified sunflower and soybean seeds. Improvements
were made to the analytical methods to accomplish these analyses successfully. Triacylglycerols (TAG) were separated on two
300 mm × 3.9 mm 4μ Novapak C18 high-performance liquid chromatography (HPLC) columns and detected with a Varex MKIII evaporative
light-scattering detector. Peaks were identified by coelution with known standards or by determining fatty acid composition
of eluted TAG by capillary gas chromatography (GC). Stereospecific analysis (fatty acid position) was accomplished by partially
hydrolyzing TAG with ethyl magnesium bromide and immediately derivatizing the resulting diacylglycerols (DAG) with (S)-(+)-1-(1-naphthyl)ethyl isocyanate. The derivatized sn-1,2-DAG were completely resolved from the sn-2,3-DAG on two 25 mm × 4.6 mm 3 μ silica HPLC columns. The columns were chilled to −20°C to obtain baseline resolution of
collected peaks. The distribution of fatty acids on each position of the glycerol backbone was derived from the fatty acid
compositions of the two DAG groups and the unhydrolyzed oil. Results for the sn-2 position were verified by hydrolyzing oils with porcine pancreatic lipase, isolating the resulting sn-2 monoacylglycerols by TLC, and determining the fatty acid compositions by GC. Results demonstrated that alterations in the
total fatty acid composition of these seed oils are determined by the concentration of TAG species that contain at least one
of the modified acyl groups. As expected, no differences were found in TAG with fatty acid quantities unaffected by the specific
mutation. In lieu of direct metabolic or enzymatic assay evidence, the authors’ positional data are nevertheless consistent
with TAG biosynthesis in these lines being driven by the mass action of available acyl groups and not by altered specificity
of the acyltransferases, the compounds responsible for incorporating fatty acids into TAG. 相似文献
47.
Timothy D. Davis Julia DiCorleto David Sheldon Jodi Vecchiarelli Can Erkey 《The Journal of Supercritical Fluids》2004,30(3):349-358
A novel route for the production of highly porous vitrified grinding wheels was developed via selective extraction of pore inducers with dense CO2. The extraction was performed with liquid and supercritical CO2 (scCO2) at temperatures ranging from 295 to 338 K, pressures from 8.8 to 27.6 MPa and flow rates of 3.4×10−5 and 7.5×10−5 kg s−1 CO2. The extraction rate was a strong function of temperature, flow rate, and flow direction, while unaffected by particle size of the pore inducer and pressure. The extraction had no detrimental effect on the green wheel’s microstructure. Grinding tests were performed on the CO2 extracted pore induced wheels and results were compared to those from a conventionally manufactured pore induced grinding wheel. The extracted grinding wheels performed similarly to the conventional wheels. At high metal removal rates, the extracted wheels with large pore sizes outperformed the wheels with smaller particle sizes as well as the conventional wheel. This may be due to the larger pore sizes increasing lubrication at the surface and increasing the wheel strength. 相似文献
48.
David G Gilbert Adam Izetelny Robert Radtke Jonathan Hammersley Norka E Rabinovich Travis R Jameson Jodi I Huggenvik 《Nicotine & tobacco research》2005,7(3):361-379
The effects of nicotine, distractor type, and dopamine type-2 receptor (DRD2) genotype on rapid visual information processing (RVIP) task performance were assessed in habitual smokers. Four RVIP tasks differed in terms of distractor location (central vs. peripheral) and distractor type (numeric vs. emotional). Each participant performed each of the tasks on two different days, once while wearing an active nicotine patch and once while wearing a placebo patch. Overall, the nicotine patch produced more accurate detection of and faster reaction times to target sequences; however, these effects varied with distractor type and genotype. Nicotine speeded reaction time more with left-visual-field (LVF) than right-visual-field (RVF) emotional distractors but speeded reaction time more with RVF than LVF numeric distractors, especially when the distractor digit matched the target sequence in terms of numeric oddness or evenness. Nicotine tended to facilitate performance more in individuals with at least one A1 allele than in homozygous A2A2 individuals, especially with numeric distractors presented to the left hemisphere. Nicotine tended to reduce distraction by negative stimuli more than other types of stimuli. Few gender differences were observed. The overall pattern of results was consistent with the view that nicotine modulates selective attention or subsequent information processing in a manner that depends partly on the emotional versus numeric nature of task distractors, DRD2 genotype, and the brain hemisphere that initially processes the distractors (visual field of distractor). 相似文献
49.
Odorants that Induce Hygienic Behavior in Honeybees: Identification of Volatile Compounds in Chalkbrood-Infected Honeybee Larvae 总被引:3,自引:0,他引:3
Jodi A. I. Swanson Baldwyn Torto Stephen A. Kells Karen A. Mesce James H. Tumlinson Marla Spivak 《Journal of chemical ecology》2009,35(9):1108-1116
Social insects that live in large colonies are vulnerable to disease transmission due to relatively high genetic relatedness
among individuals and high rates of contact within and across generations. While individual insects rely on innate immune
responses, groups of individuals also have evolved social immunity. Hygienic behavior, in which individual honeybees detect
chemical stimuli from diseased larvae and subsequently remove the diseased brood from the nest, is one type of social immunity
that reduces pathogen transmission. Three volatile compounds, collected from larvae infected with the fungal pathogen Ascosphaera apis and detected by adult honey bees, were identified by coupled gas chromatography-electroantennographic detection and gas chromatography-mass
spectrometry. These three compounds, phenethyl acetate, 2-phenylethanol, and benzyl alcohol, were present in volatile collections
from infected larvae but were absent from collections from healthy larvae. Two field bioassays revealed that one of the compounds,
phenethyl acetate is a key compound associated with Ascosphaera apis-infected larvae that induces hygienic behavior. 相似文献
50.
Metzger Richard L.; Warren Amye R.; Shelton Jill T.; Price Jodi; Reed Andrea W.; Williams Danny 《Canadian Metallurgical Quarterly》2008,44(1):169
The Deese/Roediger-McDermott (DRM) paradigm was used to investigate developmental trends in accurate and false memory production. In Experiment 1, DRM lists adjusted to be more consistent with children's vocabulary were used with 2nd graders, 8th graders, and college students. Accurate and false recall and recognition increased with age, but semantic information appeared to be available to all age groups. Experiment 2 created a set of child-generated lists based on the free associations by a group of 3rd graders to critical items. The child-generated associates were different from those generated by adults; long and short versions of the child-generated lists were therefore presented to 2nd, 5th, and 8th graders and college students in Experiment 3. Second graders exhibited few false memories, whereas 5th graders were similar to adults in low-demand conditions and more similar to younger children in high-demand conditions. Findings are discussed in terms of developmental changes in automatic and effortful processing and the use of semantic networks. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献