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1.
The major sex attractant of the oak leaf roller (Archips semiferanus Walker),cis-10-tetradecenyl acetate (I), was synthesized in 55–62% overall yield by a highly economical route from inexpensive azelaic acid (II).Authorized as Paper No. 4779 in the Journal Series of the Pennsylvania Agricultural Experiment Station.  相似文献   
2.
The lipids of the thermophilic fungusHumicola grisea var.thermoidea were qualitatively and quantitatively determined. The polar lipids consisted of 38.4–42.3% of the total lipids. The relative per cent phospholipids based upon the total phospholipids were as follows: phosphatidyl choline, 32.3–33.7%; phosphatidic acid, 24.5–31.7%; phosphatidyl ethanolamine, 15.8–20.9%; phosphatidyl inositol, 12.5–13.0%; phosphatidyl serine, 2.3–5.4%; and diphosphatidyl glycerol, 3.9–4.0%. The relatively high concentration of phosphatidic acid may be characteristic of fungi grown at elevated temperatures. Several sterol glycosides (3.1–6.0%) were present in the polar lipids. The neutral lipids consist of triglycerides, 28.6–36.0%; free fatty acids, 5.3–13.5%; sterols, 11.4–13.9%; sterol esters, 1.8–3.0%; and diglycerides, 2.2–3.4%. The sterols and derivatives comprise an unusually large fraction of the total lipids (16.3–22.9%) suggesting a role in thermostability.  相似文献   
3.
Geraniums (Pelargonium xhortorum Bailey) possess a pest-resistance mechanism, based on glandular trichomes and the exudate they produce, that has been shown to be effective against the two-spotted spider mite (Tetranychus urticae Koch). Using an intact plant bioassay, the effectiveness of the resistance mechanism was determined for another potential pest, the foxglove aphid (Acyrthosiphon solani Kaltenbach). Comparisons were made between plant lines previously analyzed for their degree of resistance to mites, as well as their glandular trichome density and trichome exudate production. Over 100 aphid adults were bioassayed on each of the five plant lines used in the experiment. In addition to adult aphid survival, the production and survival of nymphs was determined in this bioassay. The results indicate that plant lines that are resistant to the two-spotted spider mite are also resistant to the foxglove aphid, while lines susceptible to mites are susceptible to the aphids. To evaluate the physical impediment features of the trichome exudate, the behavior of foxglove aphid nymphs was compared on two geranium lines, one a resistant line with high trichome densities and large quantities of exudate and the second a susceptible line with few trichomes and reduced exudate. A third leaf surface type was produced by washing the exudate from resistant leaves using a mildly basic buffer solution prior to the bioassay. Aphid behavior was divided into five categories: feeding or probing, resting, wandering, struggling, and immobilized. On both susceptible leaves and resistant leaves from which the exudate had been removed by washing, the aphids settled quickly and were observed with inserted stylets during most of the observation intervals. In contrast, aphids on the unwashed resistant leaf surfaces often became ensnared in the sticky trichome exudate and had difficulty in settling to probe the leaf. Physical entrapment by glandular trichome exudate appears to be an important aspect of aphid resistance in geraniums.  相似文献   
4.
This article describes a method for the intraindividual clinical validation of a cognitive case formulation (CCF) involving hypotheses about the patient's idiosyncratic cognitive schema (ICS). The two-stage approach begins by testing the convergent and discriminant validity of the hypothesized ICS against the individual's daily ratings of cognition items using confirmatory dynamic factor analysis. The second stage evaluates the extent to which the ICS factor scores predict daily variability in symptoms and distress and further addresses convergent and discriminant validity by evaluating intraindividual cognitive content specificity and the incremental validity of the idiographic cognition factors compared with nomothetic measures of thoughts/beliefs. This approach to validating idiographic assessment is illustrated with the CCF of a woman with comorbid mood and anxiety disorders. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
5.
Anacardic acids, alkyl phenolic acids excreted by tall glandular trichomes of the garden geranium, Pelargonium xhortorum, confer small-pest resistance. Up to 90% of the trichome exudate from mite-resistant P. xhortorum inbreds consists of an unusual anacardic acid with an unsaturated omega-5 (5) alkyl chain. As fatty acids are biochemical precursors to anacardic acids, we examined by GC the fatty acid composition of leaves, pedicels, petals, sepals, mature seeds, and glandular trichomes from pest-resistant and pest-susceptible Pelargonium inbred lines to determine the localization of 5-fatty acids within plant tissues. The fatty acid composition of lipid classes (galactolipids, phospholipids, and neutral lipids) extracted from glandular trichomes from mite-resistant pedicels were also examined. 5-Fatty acids (16:111 and 18:113) were found only in the glandular trichomes from pest-resistant geraniums (27.2% in trichomes of pedicels) and were localized predominantly in the phospho- and galactolipids (phosphatidylinositol, 25.9%; phosphatidylcholine, 18.2%; monogalactosyldiglyceride, 15.5%; and diglactosyldiglyceride, 14.0%).  相似文献   
6.
The uptake of selected steroids and norsesquiterpenes by live minnows,Pimephales promelas, was studied when the compounds were administered externally in aqueous solution. The gills of minnows absorbed 80% of the steroid removed from solution. Steroid absorption across minnow gills is apparently a nonmediated process as rate saturation could not be demonstrated. Initial absorption rates of test compounds were inversely correlated with (1) the degree of oxygenation, (2) water solubility, and (3) polarity on silica gel thin-layer chromatography. These findings support the Stein model of non-mediated transport. The majority of compounds anesthetic and toxic to minnows exerted their effects at a similar internal concentration. Anesthesia occurred at ca. 10–6–10–5 M and death at 10–4–10–3 M. Since various agents causing membrane stabilization and lysis in in vitro systems act in an identical concentration range, it is proposed that the defensive steroids and norsesquiterpenes of water beetles act via membrane stabilization and lysis.  相似文献   
7.
The analytical energy performance of an advanced energy optimized-ventilation constrained control approach to variable air volume systems was compared to four other controls. The other controls are either currently used or have been proposed in the literature. The advanced control demonstrated its potential to meet the ventilation requirements of ASHRAE Standard 62–1989 for every zone of the building with minimal energy consumption.

The analytical work was carried out in a single story prototypical commercial building. The building was analyzed in five US cities to provide insight into the impact of climate on the performance of the advanced control. The advanced control consumed less total energy, considerably less in some cities, than the other four controls. The advanced control provides an excellent opportunity to apply to buildings new automation equipment and software never attempted before.  相似文献   

8.
Advances in the understanding of lung cancer biology have led to observations that specific genetic changes occur in premalignant dysplasia. These observations have occurred predominantly in molecular studies of resected lung tumors and consequently, they may not be fully representative of those biological abnormalities characterizing premalignant lesions in individuals without overt lung cancer. Studies of premalignant epithelial cell biology and chemoprevention are needed in this patient subgroup. Such an initiative is now underway through the lung cancer Specialized Program of Research Excellence (SPORE) grant awarded to the University of Colorado Cancer Center (and affiliated institutions) by the National Cancer Institute. To identify participants for the early detection and chemoprevention trials of the Colorado SPORE, we initiated a sputum cytology screening program targeting persons with chronic obstructive pulmonary disease and smoking histories of 40 or more pack-years. During the first 26 months after activation of the screening program, sputum samples from 632 participants were evaluated. Of these, 533 (84%) of the subjects submitted specimens deemed adequate for cytopathological interpretation; 99 (16%) provided sputum samples unsuitable for cytodiagnosis. Of those participants who submitted adequate samples, 48% had cytodiagnoses of mild dysplasia, 26 % had moderate to severe dysplasia, and 2% presented with carcinoma in situ or invasive carcinoma. Logistic regression modeling was pursued to determine whether selected demographic and/or clinical status variables could be identified as statistically significant predictors of the specific cytological outcome to be expected (mild dysplasia, moderate dysplasia, and so forth). The only apparent associations found from both univariate and multivariate analyses were that the total number of pack-years of smoking history decreased with severity of cytodiagnosis and that those individuals with mild or moderate dysplasia were more likely to be ex-smokers than those with grades of regular metaplasia or lower. Based on the initial results of the Colorado SPORE sputum cytology screening program, we conclude that persons with chronic obstructive pulmonary disease and 40 or more pack-years of smoking history have a high prevalence of premalignant dysplasia detectable through sputum cytology and should be targeted for research programs focusing on lung cancer prevention, early detection, and exploratory biomarker studies.  相似文献   
9.
High-resolution spectroscopy of Mars' atmosphere with the Hubble Space Telescope revealed the deuterium Lyman alpha line at an intensity of 23 +/- 6 rayleighs. This measured intensity corresponds to HD/H2 = 1.5 +/- 0.6 x 10(-4), which is smaller by a factor of 11 than HDO/H2O. This indicates that fractionation of HD/H2 relative to that of HDO/H2O is not kinetically controlled by the rates of formation and destruction of H2 and HD but is thermodynamically controlled by the isotope exchange HD + H2O left and right arrow HDO + H2. Molecular hydrogen is strongly depleted in deuterium relative to water on Mars because of the very long lifetime of H2 (1200 years). The derived isotope fractionation corresponds to an estimate of a planetwide reservoir of water ice about 5 meters thick that is exchangeable with the atmosphere.  相似文献   
10.
The garden geranium (Pelargonium xhortorum) has been shown to secrete anacardic acids in the form of a viscous sticky exudate from tall glandular trichomes, and this exudate provides a sticky trap defense against small pest species. The anacardic acids from genetically related pest-resistant and -susceptible plants have been characterized, and resistance has been shown to depend upon the presence of5 unsaturated anacardic acids. In this study, the biosynthesis of these anacardic acids was comparatively investigated by incubating [14C]methyl palmìtate, margarate, stearate, oleate and linoleate on floral buds of resistant and susceptible plants. In addition, the incorporation of [14C]valine, -isoleucine, and -leucine into anacardic acids was also studied. Nineteen anacardic acids were quantitated utilizing an improved HPLC technique. Fatty acids and, to a much lesser extent, amino acids were incorporated into anacardic acids. There are at least two pathways of biosynthesis operating: direct elongation, and -oxidation with reincorporation of the [14C]acetate, the latter being more prevalent in the resistant plant. The amino acids were processed into branched chain anacardic acids, isoleucine being the precursor of the anteiso compounds, and valine the iso branched ones. The major difference between resistant and susceptible plants was the ability of resistant plants, but not the susceptible plants, to synthesize5 unsaturated anacardic acids. Both types of plants were capable of directly incorporating14C-labeled fatty acid methy esters into anacardic acids regardless of the plant's normal anacardic acid composition, thus bypassing the plant's tightly controlled regulation of the chemical structures of anacardic acids. No evidence was found for5 desaturation of saturated anacardic acids. A revised biosynthesis scheme is presented.  相似文献   
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