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71.
Summary The interference of certain unsaturated hydroxy acids in the Durbetaki method of epoxide determination has been demonstrated. The concentrations of these constituents were determined concurrently with those of epoxy components by measurement of the near infrared spectra of samples before and after treatment with anhydrous ethereal hydrogen chloride. The individual hydroxy esters were separated and isolated from samples of mixed esters by thinlayer chromatography. GLC of these esters resulted in their alteration to conjugated trienoates and gave proof of their conjugated diene hydroxyl structure. Thin-layer chromatographic and infrared studies verified theTrans-trans diene unsaturation of the acid fromDimorphotheca aurantiaca oil and showed that the other hydroxy compounds examined have acistrans diene system. These data suggest that the seed oils ofArtemisia absinthium, Calliandra eriophylla, Balanites aegyptica, Cosmos bipinnatus, and Helianthus annuus contain 9-hydroxy-trans-10-cis-12- and 13-hydroxy-cis-9-trans-11-octadecadienoic acids. Supported by grants from The Hormel Foundation and the National Institutes of Health (Research Grant No. H-3559), and presented in part at the 33rd fall meeting, American Oil Chemists’ Society, Los Angeles, Calif., September 28–30, 1959. Fulbright Scholar to the Hormel Institute, 1958–1960.  相似文献   
72.
Geometric and positional isomers of [1-14C] octadecenoic acids have been synthesized by modifications of published procedures. Positional isomers of octadecynoic acids also have been synthesized to obtain the geometric and positional isomers of the unlabeled octadecenoic acid analogs. The syntheses were accomplished by coupling a haloalkyl compound with a substituted acetylene using n-butyl lithium in hexamethylphosphoramide. The coupled product, either a 17-or 18-carbon acetylenic alcohol, could be semihydrogenated and chain extended to afford a carboxy labeled derivative, could be partially hydrogenated and chain extended to afford a carboxyl labeledcis-ortrans-octadecenoic acid in the former case. In the latter case, octadecynoic,cis-octadecenoic ortrans-octadecenoic acids could be obtained by the appropriate reactions. The methods used in this study enabled the synthesis of14C-labeled fatty acids in generally higher yields and by simpler reactions than were previously possible.  相似文献   
73.
74.
Examined the effects of hemodialysis type (staff controlled, in center vs patient controlled, home) and patient preference for behavioral involvement on adherence and emotional adjustment in 53 adult patients with end-stage renal disease. Measures included the Krantz Health Opinion Survey and the Beck Depression Inventory. Higher levels of preference for behavioral involvement were associated with better dietary adherence (i.e., lower serum potassium) for Ss receiving dialysis at home but worse dietary adherence for Ss receiving treatment in a dialysis center. A similar, though weaker, patient by treatment type matching pattern was observed for fluid-intake adherence (i.e., interdialytic weight gain). Self-reported depression did not seem to affect adherence. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
75.
A method for the analysis of fatty esters employing separation by thin-layer chromatography and quantitative determinationvia their hydroxamic acids has been developed. Esters of different types are separated on silica gel plates, the spots or zones are scraped from the plates, the esters are extracted from the silica gel, and the iron hydroxamic acid complexes are formed. The latter are then measured by colorimetry. The method is suitable for analysis of mixtures of ordinary, epoxy, monohydroxy, and dihydroxy fatty esters as well as for mixtures of mono-, di-, and triglycerides. Used in conjunction with gas chromatography this method permits the fatty acid composition of seed oils containing oxygenated fatty acids to be measured in about 3 hours. The amount required for the total analysis is 1 to 10 mg. per determination, depending upon composition. Presented at the Spring Meeting, American Oil Chemists' Society, St. Louis, May, 1–3, 1961. Supported by the Hormel Foundation, the National Institutes of Health (Research Grant H-3559), and the National Dairy Council. Appointment supported by the International Cooperation Administration under the Visiting Research Scientists Program of the U.S.A.  相似文献   
76.
An experimental 576 K BiCMOS emitter-coupled-logic (ECL)-compatible SRAM that achieves 3.5-ns access and cycle is discussed. The SRAM is fully self-testable using less than 1 K on-chip logic gates to assist characterization, wafer testing, and package testing. The I/O is also transistor-transistor-logic (TTL) programmable with the first-metal mask  相似文献   
77.
(i) Image registration. The use of serial images for computerised three-dimensional reconstruction necessitates the inclusion of three separate sources of information at the stage of data input. These are (i) artificial registration points or fiducials, (ii) a calibration scale and (iii) an outline of each slab of the section to be included in the reconstruction. Most traditional methods rely on the production of drawings of the contours of the structure under investigation which also include both registration points and a calibration scale. We report on a method which considerably reduces the time involved at this labour intensive stage of reconstruction and in addition allows subsequent reconstructions of different structures to be performed without new drawings. Use is made of computerised alignment of tissue sections and the production of composite photomicrographs of both the tissue under investigation and an accurately registered stage micrometer scale. (ii) Improving image interpretation. Images derived from computerised three-dimensional reconstruction can be affected by the number of coordinates used to form the contour of each slice of a structure and by the number of slices that are used to construct the final model. Too little or too much data can considerably reduce the ability of the observer to interpret accurately the image generated by the computer. We report on a feature-based method which enables the experimenter to assess objectively the amount of data required in the two-dimensional plane, i.e. the number of data points per slice, and the three-dimensional plane, i.e. number of slices per structure, so that optimal reconstructions are generated.  相似文献   
78.
79.
This paper explores the factors that shape the location choices of formerly mobile graduates (FMGs) initially resident in Sardinia, Italy, a less developed European region. Combining qualitative and quantitative techniques, the paper examines the reasons why some individuals decide to return after their studies, the factors that shape their decisions and how these choices unfolded in space and time. It counters the literature, which suggests that migration is a one-off linear process driven only by wealth-maximising behaviour, positing rather that access to opportunities in open meritocratic job markets and circular migration trajectories are far more salient to FMGs. This suggests that policy makers should concentrate on promoting labour market opportunities and invest in social networks that will aid brain circulation.  相似文献   
80.
Collective traumas can negatively affect large numbers of people who ostensibly did not experience events directly, making it particularly important to identify which people are most vulnerable to developing mental and physical health problems as a result of such events. It is commonly believed that successful coping with a traumatic event requires expressing one's thoughts and feelings about the experience, suggesting that people who choose not to do so would be at high risk for poor adjustment. To test this idea in the context of collective trauma, 2,138 members of a nationally representative Web-enabled survey panel were given the opportunity to express their reactions to the terrorist attacks of September 11, 2001, on that day and those following. Follow-up surveys assessing mental and physical health outcomes were completed over the next 2 years. Contrary to common belief, participants who chose not to express any initial reaction reported better outcomes over time than did those who expressed an initial reaction. Among those who chose to express their immediate reactions, longer responses predicted worse outcomes over time. Implications for myths of coping, posttrauma interventions, and psychology in the media are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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