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Unexpected Result (unexpected + result)
Selected AbstractsChemInform Abstract: Unexpected Result from the Interaction of 1,8-Diaminonaphthalene with Aromatic Nitriles in Polyphosphoric AcidCHEMINFORM, Issue 5 2008I. V. Aksenova Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Unexpected Result of Imidazo[4,5-b]pyridine Bromination.CHEMINFORM, Issue 46 2003Yu. M. Yutilov No abstract is available for this article. [source] ChemInform Abstract: Unexpected Results from the Reinvestigation of the Beckmann Rearrangement of Ketoximes into Amides by Using TsCl.CHEMINFORM, Issue 3 2010Hong-Jun Pi Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a "Full Text" option. The original article is trackable via the "References" option. [source] Unexpected Results in the Friedlaender Reaction of 4-Aryl-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H- [1]benzopyran-3-carbonitriles.CHEMINFORM, Issue 1 2007Rafael Leon Abstract ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF. [source] 1,8-Bis(dialkylamino)-4,5-dinitronaphthalenes and 4,5-Bis(dimethylamino)naphthalene-1,8-dicarbaldehyde as "Push,Pull" Proton Sponges: When and Why Formyl Groups Become Stronger ,-Electron Acceptors than Nitro GroupsEUROPEAN JOURNAL OF ORGANIC CHEMISTRY, Issue 8 2009Valery A. Ozeryanskii Abstract Single-crystal X-ray studies of four representatives of "push,pull" proton sponges, namely 1,8-bis(dimethylamino)-, 1,8-bis(diethylamino)-, 1,8-bis(dipropylamino)-4,5-dinitronaphthalenes and 4,5-bis(dimethylamino)naphthalene-1,8-dicarbaldehyde have been performed at low and ambient temperatures. The most interesting and unexpected result is that the formyl groups in the peri -dialdehyde display stronger ,-acceptor effects than the nitro groups. This phenomenon is ascribed to smaller steric demands of the CHO groups, their lower electrostatic repulsion, and specific packing forces. The naphthalene cores of all but one of the molecules are markedly twisted (21,26°) while that of the diethylamino derivative is not (<5°), providing different and somewhat unpredictable ways of resonance stabilization and steric relaxation. The through-conjugation in the above compounds is also discussed for gas and solution phases on the basis of theoretical calculations, UV/Vis and 1H NMR spectra.(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009) [source] Foraging by fearful frugivores: combined effect of fruit ripening and predation riskFUNCTIONAL ECOLOGY, Issue 6 2006J. M. FEDRIANI Summary 1Plant defensive compounds and predation risk are main determinants of herbivore foraging, though empirical studies have seldom measured the combined effects of these two factors. By considering the interaction between the herb Helleborus foetidus and its main fruit and seed predator, the Wood Mouse Apodemus sylvaticus, we evaluated whether the defensive role against seed predators of compounds present in H. foetidus unripe fruits holds across a micro-landscape that differs in foraging costs (i.e. predation risk). 2First, we used standardized food patches that simulated fruiting H. foetidus plants to ascertain fruit preferences of captive mice. Then, by means of field experiments, we assessed the combined effects of fruit ripening and predation risk on foraging by free-ranging mice. 3Captive mice avoided plants with unripe fruit and avoided consuming unripe fruits within a particular plant. Free-ranging mice also avoided unripe fruits in safe microhabitats (rocky substrate), but not in risky microhabitats (bare ground) where few fruits were consumed. This unexpected result may be driven by predation risk experienced by mice foraging on H. foetidus fruits, and/or plant defensive compounds acting in a dose-dependent manner. 4Frugivorous mice responded to both chemical defences present in unripe H. foetidus fruits as well as to predation cost though such response was sequential. Plant defence compounds appeared to play a part in mouse foraging only after mice selected low predation risk microhabitats. 5Our study indicates that both digestive and ecological factors influence foraging decisions, which in turn affects pressures exerted by herbivores on plant populations. [source] A role for endogenous reverse transcriptase in tumorigenesis and as a target in differentiating cancer therapyGENES, CHROMOSOMES AND CANCER, Issue 1 2006Paola Sinibaldi-Vallebona An unexpected result emerging from completion of the genome sequencing project is that a large portion of mammalian genomes is constituted by retrotransposons. A large body of published data supports the conclusion that retrotransposons are biologically active elements and indicates that retrotransposition is an ongoing process in mammalian genomes. Retroelements can act as insertional mutagens altering the coding integrity of genes and, recently, have been found to also affect the expression of cellular genes at the epigenetic level: in this light, they are a potential threat in that these events can trigger the onset of several pathologies including cancer. Retroelement genes, and particularly the gene coding for reverse transcriptase (RT), are typically expressed at high levels in transformed cells and tumors. In recent work, we have found that drug-mediated inhibition of the endogenous RT activity, or silencing of expression of active retrotransposons of the LINE-1 family by RNA interference, down-regulate cell growth and induce the activation of differentiating functions in several cancer cell lines. Moreover, the inhibition of endogenous RT activity in vivo antagonizes the growth of human tumors in animal models. In this review, we discuss newly emerging concepts on the role of retrotransposons and suggest that an abnormally high level of the RT activity that they encode may contribute to the loss of control in the proliferation and differentiation programs typical of transformed cells. In this light, RT-coding elements may be regarded as promising targets in the development of novel, differentiation-inducing approaches to cancer therapy. © 2005 Wiley-Liss, Inc. [source] Contemporary climate change in the Sonoran Desert favors cold-adapted speciesGLOBAL CHANGE BIOLOGY, Issue 5 2010SARAH KIMBALL Abstract Impacts of long-term climate shifts on the dynamics of intact communities within species ranges are not well understood. Here, we show that warming and drying of the Southwestern United States over the last 25 years has corresponded to a shift in the species composition of Sonoran Desert winter annuals, paradoxically favoring species that germinate and grow best in cold temperatures. Winter rains have been arriving later in the season, during December rather than October, leading to the unexpected result that plants are germinating under colder temperatures, shifting community composition to favor slow growing, water-use efficient, cold-adapted species. Our results demonstrate how detailed ecophysiological knowledge of individual species, combined with long-term demographic data, can reveal complex and sometimes unexpected shifts in community composition in response to climate change. Further, these results highlight the potentially overwhelming impact of changes in phenology on the response of biota to a changing climate. [source] Effects of temperature and fertilization on nitrogen cycling and community composition of an urban lawnGLOBAL CHANGE BIOLOGY, Issue 9 2008NEETA S. BIJOOR Abstract We examined the influence of temperature and management practices on the nitrogen (N) cycling of turfgrass, the largest irrigated crop in the United States. We measured nitrous oxide (N2O) fluxes, and plant and soil N content and isotopic composition with a manipulative experiment of temperature and fertilizer application. Infrared lamps were used to increase surface temperature by 3.5±1.3 °C on average and control and heated plots were split into high and low fertilizer treatments. The N2O fluxes increased following fertilizer application and were also directly related to soil moisture. There was a positive effect of warming on N2O fluxes. Soils in the heated plots were enriched in nitrogen isotope ratio (,15N) relative to control plots, consistent with greater gaseous losses of N. For all treatments, C4 plant C/N ratio was negatively correlated with plant ,15N, suggesting that low leaf N was associated with the use of isotopically depleted N sources such as mineralized organic matter. A significant and unexpected result was a large, rapid increase in the proportion of C4 plants in the heated plots relative to control plots, as measured by the carbon isotope ratio (,13C) of total harvested aboveground biomass. The C4 plant biomass was dominated by crabgrass, a common weed in C3 fescue lawns. Our results suggest that an increase in temperature caused by climate change as well as the urban heat island effect may result in increases in N2O emissions from fertilized urban lawns. In addition, warming may exacerbate weed invasions, which may require more intensive management, e.g. herbicide application, to manage species composition. [source] Does market misvaluation help explain share market long-run underperformance following a seasoned equity issue?ACCOUNTING & FINANCE, Issue 2 2006Philip Brown G10; G14 Abstract We examine the relation between pre-seasoned equity offering (SEO) announcement date misvaluation and long-run post-SEO performance for a large sample of Australian SEOs made between 1993 and 2001. Our study is motivated by inconsistent findings across countries with respect to the SEO long-run underperformance anomaly first documented in the USA, inconclusive findings with respect to the hypothesis that managers exploit market misvaluation when timing equity issues, and a recent Australian Stock Exchange proposal to loosen SEO regulation. We find SEO firms underperform common share market benchmarks for up to 5 years after the announcement. Using a residual income valuation method, we show that this underperformance is related to pre-announcement date misvaluation. An unexpected result is that underperformance and misvaluation are more severe for private placements than rights issues. Institutional factors unique to the Australian setting, particularly the large number of smaller loss-making firms among private placement issuers, appear to explain the poorer performance of placement firms. Our results are robust to various measurement methods and assumptions, and demonstrate the importance of researching SEO performance in alternative institutional settings. [source] Are there correlates of male Australian Magpie Gymnorhina tibicen reproductive success in a population with high rates of extra-group paternity?IBIS, Issue 2 2006KATE L. DURRANT The reproductive success of a male bird is often correlated with measurable traits that predict his intrinsic quality. Females are thought to base their selection of mates on the latter's ,quality' in order to gain their ,good genes'. Male Australian Magpies Gymnorhina tibicen of the white-backed race tyrannica were trapped in two breeding seasons. Measurements were taken of morphometric and other characteristics in order to discover whether particular traits of males were associated with: (1) percentage of offspring sired in the territory, (2) number of fledglings produced in the territory per season and (3) whether females select males for their ,good genes'. There were no consistently significant correlations between any of the measured variables and male Magpie reproductive success within territories. In particular, none of the traits measured had any consistent correlation with the percentage of offspring sired in a territorial group. This was an unexpected result given that the species is strongly territorial but also engages regularly in extra-group copulations. These findings appear contrary to the predictions of the ,good genes' hypothesis. The general lack of correlation between the variables and level of genetic paternity may in fact be due to females engaging in extra-group mating primarily to avoid breeding with a close relative rather than to choose a high-quality male. In this case, males would not have to be ,high quality', but merely genetically different from the female's social mate. [source] Brazilian attitudes toward English: dimensions of status and solidarityINTERNATIONAL JOURNAL OF APPLIED LINGUISTICS, Issue 1 2001Linda Gentry El-Dash The implications of the prestige and vitality of English as a foreign language in Brazil were investigated using both direct and indirect measures of attitudes and beliefs (a subjective vitality questionnaire and a classic matched-guise instrument). Aspects of solidarity and status identi ?ed by factor analysis were investigated in a Brazilian adolescent population, and four statistically distinctive pro ?les were found. Approximately half of the subjects evaluated English-speaking guises more favorably than those of the native Portuguese in terms of status,which is typical of the adult population, who tend to feel the prestige of English as an international language, but half also valued this guise in terms of solidarity, a totally unexpected result which was attributed to the symbolic use of English within the adolescent peer group. [source] Bone weight: new reference values based on a modern Portuguese identified skeletal collectionINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 5 2009A. M. Silva Abstract Skeletal weight and/or weight of the different bones of the human skeleton are currently used in a wide range of applications such as archaeological cremations and forensics. Still, few reference values are available that compare the mean weights for the different skeletal parts. In this paper we present new reference values for total skeletal weight, including the weight of the different skeletal bones based on a modern Portuguese Identified Skeletal Collection (CEI) curated in the Museum of Anthropology of the University of Coimbra (Portugal). The mean weight of the entire skeleton for the CEI pooled sample is 3323.8,±,779.6,g. Sex and age differences were investigated. As expected, males display heavier bones, at a statistically significant level. The mean weight of the male skeletons is 3850,g, and 2797.6,g for the female sample. Age differences were found, especially for the female samples in the 29,39 versus 50,59,and/or >60 age groups, probably as a consequence of age-related bone loss in post-menopausal women. For the male sample, no clear age-related trend was observed but for the unexpected result that the second highest bone weight recorded is in the oldest age group (>60 years). This could result from high mechanical loadings and thus greater bone robusticy and amount of cortical bone. The percentage of weight of the different parts of the skeleton was also calculated. These new values can be quite useful in the study of very fragmentary and/or commingled human remains, recovered from historic or forensic contexts, since the complete identification, by side, of the remains is not necessary. Copyright © 2008 John Wiley & Sons, Ltd. [source] A Late Neolithic vertebrate food web based on stable isotope analysesINTERNATIONAL JOURNAL OF OSTEOARCHAEOLOGY, Issue 4 2006C. Bösl Abstract Stable carbon and nitrogen isotope analyses of bone collagen, and stable carbon and oxygen isotope analyses of the bone's structural carbonate, were performed on 120 individuals representing 33 vertebrate species, including a single human bone find, collected from the Late Neolithic settlement at Pestenacker, Bavaria, Germany. We were thus capable of reconstructing a rather complex food web and could also address particular issues, such as whether humans influenced the diet of their domestic animals as opposed to their wild relatives, or whether humans perhaps had to compete over food with their domesticates. A rather unexpected result was that freshwater fish, which could be captured in the nearby river Lech, a major tributary of the Danube, contributed to the human diet only occasionally. As for mammals, it was also possible to recognise different trophic levels for birds and aquatic vertebrates, applying stable isotope analyses to both bone collagen and structural carbonate. In the case of fish, ,18O values at least revealed a physiological regularity in terms of temperature preference, besides diet. Conceivably, variability of ,18O in surface water as reflected, for example, by species that avoided human settlements, may help to characterise past ecosystems and to define site catchment exploited by Neolithic man in the course of food acquisition. Copyright © 2006 John Wiley & Sons, Ltd. [source] Orientation of Syndiotactic Polystyrene Crystallized in Cylindrical NanoporesMACROMOLECULAR RAPID COMMUNICATIONS, Issue 3 2009Hui Wu Abstract Syndiotactic polystyrene (sPS) nanorods with different diameters have been prepared by using anodic aluminum oxide templates, and the orientation of the sPS crystals in the nanorods has been investigated by FT-IR spectroscopy. It is found that the c axis of the ,, crystals preferentially oriented perpendicular to the axis of the nanorod, and the degree of orientation is lower as the diameter of the nanorod decreases. This unexpected result is attributed to nuclei formed at the surface of the nanopores and their subsequent growth, in addition to the preferential growth compatible with the pore direction by the nuclei formed in the bulk film and in the nanorods. [source] Association between TP53 gene ARG72PRO polymorphism and chromosome aberrations in human cancersMOLECULAR CARCINOGENESIS, Issue 6 2010Nicolay V. Litviakov Abstract It is well known that the TP53 gene considerably influences on DNA repair processes. Polymorphisms in the TP53 gene, particularly the well-known Arg72Pro in codon 72 of exon 4 (Ex4+119 G>C; rs1042522), can modify the functionality of the p53 protein and activation of DNA repair. Actually, polymorphic variants Arg and Pro were found to have different properties of regulation of TP53-dependent DNA repair target genes, that can effect various levels of chromosome aberrations in cancer patients with these genotypes. Here, we studied frequency of chromatid breaks (CB), chromosome-type aberrations (CTA) and aberrant cells (AC) in cancer patients (n,=,102) with various Arg72Pro genotypes. It was shown that the Arg variant of TP53 gene is associated with high frequency of AC and chromatid breaks. That is Arg/Arg carriers have more different chromosome aberrations in comparison to individuals with Arg/Pro and Pro/Pro genotypes (P,<,0.05). Conversely, the lowest level of AC and chromatid breaks were detected in cancer patients with the Pro/Pro genotype. A completely unexpected result was that women with Arg/Arg genotype had the most high frequency of CB and AC in comparison to Arg/Pro and Pro/Pro women carriers (P,<,0.001). In the group of male patients we did not show any differences in chromosome aberrations between carriers of Arg72Pro genotypes. In conclusion, the TP53 gene Arg72Pro polymorphism appreciably influence on occurrence of chromosome aberrations in cancer. Mol. Carcinog. © 2010 Wiley-Liss, Inc. [source] Possible causes of morphological variation in an endemic Moroccan groundsel (Senecio leucanthemifolius var. casablancae): evidence from chloroplast DNA and random amplified polymorphic DNA markersMOLECULAR ECOLOGY, Issue 2 2003Max Coleman Abstract Genetic variation was assessed in Senecio leucanthemifolius var. casablancae (Compositae), a Moroccan Atlantic coast endemic, in order to examine possible causes of atypical leaf morphology in three populations south of the known range. Evidence for introgression from S. glaucus ssp. coronopifolius and/or divergence was investigated with molecular markers. Both random amplified polymorphic DNA (RAPD) and chloroplast (cp) DNA restriction fragment length polymorphism (RFLP) differentiated the species well. Some evidence that hybridization may have occurred between the two species was provided by cpDNA markers. However, biparentally inherited RAPD markers failed to provide any support for the hypothesis that intermediate leaf morphologies in atypical populations arose through hybridization. Consequently, they are most likely to have arisen via divergence caused by drift and/or selection. Genetic distances among populations of S. leucanthemifolius were significant in all but one case. Isolation by distance was indicated by a significant positive correlation between genetic and geographical distances (r = 0.68, P = 0.01, Mantel test). These results suggest that long-distance achene dispersal is rare, despite the presence of a well-developed pappus. The observed loss of pappus at achene maturity may explain this unexpected result. Due to the morphological distinction of var. casablancae from other varieties of S. leucanthemifolius, we suggest elevation to species rank and treatment of the atypical material at infraspecific rank. [source] Possible role of the adhesin ace and collagen adherence in conveying resistance to disinfectants on Enterococcus faecalisMOLECULAR ORAL MICROBIOLOGY, Issue 6 2008G. Kayaoglu Introduction:, This study aimed to evaluate whether the presence of the ace gene and Ace-mediated binding to collagen confers on Enterococcus faecalis resistance against common endodontic disinfectants. Methods:, Isogenic strains of E. faecalis: OG1RF (wild-type) and TX5256 (ace insertion mutant of OG1RF) were grown in brain,heart infusion broth at 46°C overnight. Standardized bacterial suspensions were pretreated for 1 h either with acid-soluble collagen or acidified phosphate-buffered saline (ac-PBS). Bacteria were challenged with chlorhexidine digluconate (CHX), iodine potassium-iodide (IKI), sodium hypochlorite (NaOCl), and calcium hydroxide [Ca(OH)2]. Samples were removed at 1, 3, and 6 h, and cultured on Todd,Hewitt agar plates. Colonies were counted, the absolute values were log transformed, and the data were statistically analyzed using Fisher's least significant differences test and t -test. Results:, OG1RF was more resistant than TX5256 to IKI, NaOCl, and Ca(OH)2 (P < 0.05). Collagen-exposed OG1RF was more resistant than the ac-PBS-pretreated OG1RF against CHX at 3 h and against IKI at 1 h (P < 0.05); no significant difference was found against NaOCl. As expected, the ace mutant strain, TX5256, pretreated with collagen or ac-PBS did not differ significantly in viability when challenged with CHX, IKI, and NaOCl. An unexpected result was found for Ca(OH)2: collagen-pretreated OG1RF and TX5256 were both more susceptible than ac-PBS-pretreated OG1RF and TX5256, respectively (P < 0.05). Conclusion:, The presence of the ace gene confers resistance against IKI, NaOCl, and Ca(OH)2 on E. faecalis. Exposure to collagen makes the wild-type bacterium more resistant against CHX and IKI; however, exposure to collagen apparently decreases resistance to Ca(OH)2. [source] The effect of condensates on the characterization of transiting planet atmospheres with transmission spectroscopyMONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, Issue 2 2005Jonathan J. Fortney ABSTRACT Through a simple physical argument we show that the slant optical depth through the atmosphere of a ,hot Jupiter' planet is ,35,90 times greater than the normal optical depth. This not unexpected result has direct consequences for the method of transmission spectroscopy for characterizing the atmospheres of transiting giant planets. The atmospheres of these planets likely contain minor condensates and hazes, which at normal viewing geometry have negligible optical depth, but at slant viewing geometry have appreciable optical depth that can obscure absorption features of gaseous atmospheric species. We identify several possible condensates. We predict that this is a general masking mechanism for all planets, not just for HD 209458b, and will lead to weaker than expected or undetected absorption features. Constraints on an atmosphere from transmission spectroscopy are not the same as constraints on an atmosphere at normal viewing geometry. [source] Fluorescence of Sunscreens Adsorbed to Dielectric Nanospheres: Parallels to Optical Behavior on HaCat Cells and SkinPHOTOCHEMISTRY & PHOTOBIOLOGY, Issue 6 2006Rajagopal Krishnan Sunscreens applied to the skin are retained primarily in the stratum corneum, where they adsorb and act as a barrier preventing UV penetration to deeper layers. Photophysical properties of sunscreens have traditionally been studied either in solvents, which are very different from skin, or in skin or complex artificial skin systems, which are difficult to handle. The purpose of this study was to determine whether polystyrene nanospheres could serve as an improvement over solvents for evaluation of the photophysical properties of sunscreens without the presence of autofluorescence from and interactions with specific skin biomolecules. We used HaCat cells and excised skin for this comparative study with nanospheres. Fluorescence spectral properties of common hydrophobic sunscreens octyl salicylate, padimate O (2-ethylhexyl-4-dimethylaminobenzoate) and octyl methoxycinnamate adsorbed to 220 nm polystyrene spheres are similar to those of sunscreens adsorbed to HaCat cells and excised skin. Specifically, similarity in the emission peaks and their approximate positions, excitation peak positions and a measurable reduction in scattering upon sunscreen addition suggest that polystyrene nanospheres constitute a useful system to evaluate the photophysical properties of topical sunscreens and may serve as a model system for high-throughput evaluation of potential sunscreens. An unexpected result of this comparative study was the observation of an increase in a specific skin component emission caused by addition of padimate O. [source] Positron lifetime evolution during room temperature ageing in Al-Zn-Mg-(Cu)PHYSICA STATUS SOLIDI (C) - CURRENT TOPICS IN SOLID STATE PHYSICS, Issue 11 2009A. Dupasquier Abstract The effect on the formation of vacancy-solute clusters by the addition of small percentages of Cu to Al-Zn-Mg has been studied by positron annihilation lifetime spectroscopy. The results document the ability of Cu to increase the number of vacancies retained after quenching, by forming an additional population of vacancy-solute clusters in competition with pure Zn clusters. It has also been shown that Cu accelerates the decomposition of the alloy at 150°, thereby leaving a reduced supersaturation of the matrix after an early interruption. An unexpected result is that the curve positron lifetime vs, ageing time at RT displays the symptoms of a change in the nature of the coherent aggregates that occurs in about 10 hours of RT exposure. (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim) [source] Honeydew amino acids in relation to sugars and their role in the establishment of ant-attendance hierarchy in eight species of aphids feeding on tansy (Tanacetum vulgare)PHYSIOLOGICAL ENTOMOLOGY, Issue 4 2004J. Woodring Abstract., The ratio of the concentration of honeydew total amino acids to total sugars in the honeydew of eight species of aphids, all feeding on tansy, Tanacetum vulgare (L.), was determined and correlated with honeydew production and ant-attendance. The honeydew of the five ant-attended aphid species [Metopeurum fuscoviride (Stroyan), Trama troglodytes (v. Hayd), Aphis vandergooti (Börner), Brachycardus cardui (L.), Aphis fabae (Scopoli)] was rich in total amino acids, ranging from 12.9 to 20.8 nmol µL,1 compared with the unattended aphid Macrosiphoniella tanacetaria (Kalt.) with only 3 nmol µL,1. Asparagine, glutamine, glutamic acid and serine (all nonessential amino acids) were the predominant amino acids in the honeydew of all species. The total concentration of amino acids in the phloem sap of tansy was much higher (78.7 nmol µL,1) then in the honeydew samples, and the predominant amino acids were glutamate (34.3%) and threonine (17.7%). A somewhat unexpected result was the finding that those aphid species with the highest total amino acid concentration in the honeydew always had the highest concentration of sugars. The lowest amino acid,sugar combined value was 104,28.8 nmol µL,1 in the non ant-attended species M. tanacetaria, and the highest value was an average of 270,89.9 nmol µL,1 for the three most intensely attended aphid species M. fuscoviride, A. vandergooti and T. troglodytes. There is no evidence that any single amino acid or group of amino acids in the honeydew acted as an attractant for ant-attendance in these eight aphid species. The richness of the honeydew (rate of secretion × total concentration of sugars), along with the presence of the attractant sugar melezitose, comprised the critical factors determining the extent of ant-attendance of the aphids feeding on T. vulgare. The high total amino acid concentration in sugar-rich honeydews can be explained by the high flow-through of nutrients in aphids that are particularly well attended by ants. [source] Effects of sugar feeding on carbohydrate and lipid metabolism in a parasitoid waspPHYSIOLOGICAL ENTOMOLOGY, Issue 1 2000D.A.W.N. M. Olson Summary Lifetime patterns of carbohydrate and lipid metabolism were compared in starved and sucrose-fed adults of the parasitoid Macrocentrus grandii (Goidanich) (Hymenoptera: Braconidae). As expected, sucrose-fed individuals lived longer than did starved individuals. Macrocentrus grandii males and females eclosed with levels of simple storage sugars (presumably primarily trehalose) and glycogen that were below maximum levels recorded from sucrose-fed parasitoids. Both of these nutrients dropped to very low levels in starved individuals within 4 days post-emergence and were maintained at high levels in sucrose-fed individuals throughout their lives. Lipid reserves at emergence represented the highest lipid levels for both sexes in the two diet treatments, with levels declining over the lifetimes of males and females from both diet treatments. Our results therefore suggest that dietary sucrose is used to synthesize trehalose and glycogen, but not lipids in M. grandii. Also, in contrast to the patterns observed for the simple sugars and glycogen, lipid levels in starved individuals did not drop below levels observed in sugar-fed individuals. The average number of mature eggs carried by females at emergence was 33 and increased to approximately 85 in sucrose-fed and 130 in starved females by the age of 5 d in the absence of hosts. The egg maturation rate was therefore higher in starved than in sugar-fed females. Potential explanations for this unexpected result are discussed. [source] Effect of Oxygen on Methane Steam Reforming in a Sliding Discharge ReactorCHEMICAL ENGINEERING & TECHNOLOGY (CET), Issue 5 2006F. Ouni Abstract Hydrogen-rich gas can be efficiently produced in compact plasma reformers by the conversion of a variety of hydrocarbon fuels, including natural gas and gasoline. This article describes experimental and modeling progress in plasma reforming of methane using a sliding discharge reactor (SDR). Experiments have been carried out in a compact device operating at low consumed power (1,2,kW). Previous studies of methane steam reforming using a SDR at atmospheric pressure show promising results (H2 concentration higher than 55,%). In order to study the effect of oxygen on the methane conversion and thus hydrogen production, a small amount of oxygen in the range of 7,20,% was added to the CH4 -H2O mixture. An unexpected result was that under our experimental conditions in the SDR oxygen did not have any influence on the methane conversion. Almost the totality of added oxygen is recovered intact. Moreover, part of the H2 produced was transformed into water by reaction with O2. A model describing the chemical processes based on classical thermodynamics is also proposed. The results indicate that the reactor design has to be improved in order to increase conversion and hydrogen production. [source] Circadian changes in Drosophila motor terminalsDEVELOPMENTAL NEUROBIOLOGY, Issue 4 2007Kerstin I. Mehnert Abstract In Drosophila melanogaster, as in most other higher organisms, a circadian clock controls the rhythmic distribution of rest/sleep and locomotor activity. Here we report that the morphology of Drosophila flight neuromuscular terminals changes between day and night, with a rhythm in synaptic bouton size that continues in constant darkness, but is abolished during aging. Furthermore, arrhythmic mutations in the clock genes timeless and period also disrupt this circadian rhythm. Finally, these clock mutants also have an opposing effect on the nonrhythmic phenotype of neuronal branching, with tim mutants showing a dramatic hyperbranching morphology and per mutants having fewer branches than wild-type flies. These unexpected results reveal further circadian as well as nonclock related pleiotropic effects for these classic behavioral mutants. © 2007 Wiley Periodicals, Inc. Develop Neurobiol, 2007. [source] Implications of articulatory awareness in learning literacy in english as a second languageDYSLEXIA, Issue 2 2004Jun Yamada Abstract The articulatory awareness task, which was found by Griffiths and Frith (2002) to discriminate ex-dyslexic from non-dyslexic adults, was given to three groups of Japanese college students with different English reading abilities. Two unexpected results emerged: (1) Articulatory awareness performance was generally poor across the groups, thereby suggesting that poor articulatory awareness is not unique to dyslexia but rather to reading difficulty in general, and (2) There was a weak but significant positive correlation between articulatory awareness and English reading ability. Implications are that while articulatory awareness may not function only in dyslexia, it is embedded in a complex information-processing network involving reading acquisition. Specifically, a revised Articulatory Awareness Deficit Hypothesis is formulated, which states that poor articulatory awareness is part of articulation difficulty associated with poor phonological awareness that in turn tends to underlie dyslexia and reading difficulty. Copyright © 2004 John Wiley & Sons, Ltd. [source] The importance of interspecific interactions for breeding-site selection: peregrine falcons seek proximity to raven nestsECOGRAPHY, Issue 6 2004Fabrizio Sergio The advent of GIS is initiating a rapid increase in the utilization of wildlife-habitat models as tools for species and habitat management. However, such models rarely include estimates of interspecific interactions among explanatory variables. We tested the importance of such variables by using the peregrine falcon Falco peregrinus, a medium-sized raptor frequently reported to be affected by heterospecifics, as a model species. In an Alpine population, compared to random locations, peregrines selected breeding sites farther from conspecifics, on taller cliffs, with higher availability of farmland and closer to raven Corvus corax nests. Within suitable habitat, peregrines selected sites near ravens and far from elevations associated with golden eagle Aquila chrysaetos nests. Productivity increased with cliff size, farmland availability (rich in the local main prey) and with proximity to ravens, suggesting that the observed choices were adaptive. Finally, at the regional level, peregrine density peaked at low elevation and was positively associated with raven density. The results suggested an active breeding association of peregrines with ravens, which may provide early-warning cues against predators and safe alternative nest-sites. They also confirmed the importance of including estimates of interspecific interactions among explanatory variables, which may: 1) make models more realistic; 2) increase their predictive power by lowering unexplained variance due to unmeasured factors; 3) provide unexpected results such as the cryptic, large-scale breeding association of our study; and 4) stimulate further hypothesis formulation and testing, ultimately leading to deeper ecological knowledge of the study system. [source] Dynamics of 17,-Ethynylestradiol exposure in rainbow trout (Oncorhynchus mykiss): Absorption, tissue distribution, and hepatic gene expression patternENVIRONMENTAL TOXICOLOGY & CHEMISTRY, Issue 11 2006Ann D. Skillman Abstract 17,-Ethynylestradiol (EE2) is a synthetic estrogen identified in sewage effluents. To understand better the absorption kinetics of EE2 and the induction of vitellogenin (VTG) and estrogen receptor , (ER,) mRNA, we subjected male rainbow trout (Onchorynchus mykiss) to continuous water exposures of 125 ng/L of EE2 for up to 61 d. Trout were either repetitively sampled for blood plasma or serially killed at selected time intervals. Vitellogenin, ER, mRNA, and EE2 were measured using enzymelinked immunosorbent assay and using quantitative polymerase chain reaction and gas chromatography,mass spectrometry, respectively. In separate experiments, trout were exposed to EE2 for 7 d, and hepatic gene expression was assessed using a low- and high-density cDNA microarray. The EE2 was rapidly absorbed by the trout, with an apparent equilibrium at 16 h in plasma and liver. The ER, mRNA levels also increased rapidly, reaching near-peak levels by 48 h. In contrast, plasma levels of VTG continuously increased for 19 d. After 61 d, tissues with the highest levels of VTG were the liver, kidney, and testes. Microarray-based gene expression studies provided unexpected results. In some cases, known estrogen-responsive genes (e.g., ER,) were unresponsive, whereas many of the genes that have no apparent link to estrogen function or EE2 toxicity were significantly altered in expression. Of the two microarray approaches tested in the present study, the high-density array appeared to be superior because of the improved quality of the hybridization signal and the robustness of the response in terms of the number of genes identified as being EE2 responsive. [source] Secondary structure assignment of mouse SOCS3 by NMR defines the domain boundaries and identifies an unstructured insertion in the SH2 domainFEBS JOURNAL, Issue 23 2005Jeffrey J. Babon SOCS3 is a negative regulator of cytokine signalling that inhibits Janus kinase-signal transduction and activator of transcription (JAK-STAT) mediated signal tranduction by binding to phosphorylated tyrosine residues on intracellular subunits of various cytokine receptors, as well as possibly the JAK proteins. SOCS3 consists of a short N-terminal sequence followed by a kinase inhibitory region, an extended SH2 domain and a C-terminal suppressor of cytokine signalling (SOCS) box. SOCS3 and the related protein, cytokine-inducible SH2-containing protein, are unique among the SOCS family of proteins in containing a region of mostly low complexity sequence, between the SH2 domain and the C-terminal SOCS box. Using NMR, we assigned and determined the secondary structure of a murine SOCS3 construct. The SH2 domain, unusually, consists of 140 residues, including an unstructured insertion of 35 residues. This insertion fits the criteria for a PEST sequence and is not required for phosphotyrosine binding, as shown by isothermal titration calorimetry. Instead, we propose that the PEST sequence has a functional role unrelated to phosphotyrosine binding, possibly mediating efficient proteolytic degradation of the protein. The latter half of the kinase inhibitory region and the entire extended SH2 subdomain form a single ,-helix. The mapping of the true SH2 domain, and the location of its C terminus more than 50 residues further downstream than predicted by sequence homology, explains a number of previously unexpected results that have shown the importance of residues close to the SOCS box for phosphotyrosine binding. [source] Vaccination against hepatitis B in liver transplant recipients: Pilot analysis of cellular immune response shows evidence of HBsAg-specific regulatory T cellsLIVER TRANSPLANTATION, Issue 3 2007Tanja Bauer After liver transplantation for hepatitis-B-related diseases, patients currently receive lifelong treatment with hepatitis B immunoglobulin to prevent endogenous reinfection with hepatitis B virus (HBV). Active immunization with hepatitis B vaccine would be a preferable alternative; however, most attempts to immunize these patients with standard vaccine have failed. A recent study with a new adjuvanted hepatitis B vaccine was exceptionally successful, leading to a high-titered long-lasting antibody response in 80% of all vaccinees. To identify the immunological mechanisms behind these unexpected results, the successfully vaccinated participants were tested for hepatitis B surface antigen (HBsAg)-specific T and B cells, and their cellular responses to revaccination with conventional vaccine were studied. HBsAg-specific CD4+ T lymphocytes could be detected in 13 of 16 patients after immunization with the new vaccine. Unexpectedly, these T cells produced almost exclusively interleukin (IL)-10 and had a CD4+/CD25+ phenotype. They were functionally active, suppressing cytokine secretion in HBsAg-specific (Th1) cells, thus representing antigen-specific regulatory T cells (TReg). Following a booster dose with conventional vaccine 22-31 months after completion of the initial vaccination series, the T-cell pattern in the revaccinated individuals changed substantially: 7 days after revaccination 9 of 11 individuals showed a switch to a Th1-type immune response with HBsAg-specific T cells secreting IL-2, interferon gamma and tumor necrosis factor alpha as observed in healthy controls. Four weeks after the booster, 4 patients still showed a Th1-type cytokine pattern, whereas in 5 patients only IL-10-secreting cells were detectable. After 1 year, in 3 of 4 revaccinated individuals only IL-10-secreting cells could be found, whereas the specific T cells of the fourth patient still showed a Th1-type of response. HBsAg-specific TReg cells could be demonstrated in HBV-positive liver transplant recipients successfully immunized with a new adjuvanted vaccine. Revaccination led to immediate disappearance of the these cells and the appearance of HBsAg-specific T cells with a Th1-type cytokine profile, which in most cases were replaced by the IL-10-secreting regulatory cells during the following months. The specific induction of TReg cells could contribute to the poor response of liver transplant recipients to conventional vaccine. In conclusion,, for successful vaccination of these patients, a vaccine with a strong inhibitory effect on TReg cells would be desirable. Liver Transpl 13:434,442, 2007. © 2007 AASLD. [source] | ||||||||||||||||||||||