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71.
Linden (Tilia cordata) bark was shown to contain an antifeedant effective against the large pine weevil, Hylobius abietis. Soxhlet extraction of inner and outer bark resulted in an extract that showed antifeedant activity in a microfeeding assay. The extract was fractionated by chromatography on silica gel using gradient elution with solvents of increasing polarity. The content of the fractions obtained was monitored by thin layer- and gas chromatography. Fractions of similar chemical composition were merged. Two of the 17 fractions showed antifeedant activity in the microfeeding assay. Nonanoic acid was identified in both of these fractions. Subsequent testing in the microfeeding assay showed that nonanoic acid possessed strong antifeedant activity against H. abietis adults. 相似文献
72.
R. O. Pihl; Amos Zeichner; Ray Niaura; Kristina Nagy; Camillo Zacchia 《Canadian Metallurgical Quarterly》1981,90(5):468
48 males participated in an aggression task after receiving either alcoholic or placebo beverages and after being told that they had received either a high or a low dose of alcohol. All Ss in the alcohol group actually received the same dose. Measures of aggression were the intensity and duration of shock given to a bogus partner in a RT-pain perception task and a score on a posttask attitude questionnaire. Blood alcohol readings were taken 3 times during the session, and a locus of control scale was administered before and after drinking. For Ss in the alcohol conditions, blood alcohol levels averaged .079% before the task and .085% afterwards. Alcohol resulted in higher aggression scores only on the questionnaire measure, and an interaction between drug and attribution was found for the measure of shock duration. Attribution alone resulted in greater aggression on the measure of shock intensity. Ss in groups where the attribution was discrepant with the drug condition were the most aggressive on the measures of shock intensity and duration. These Ss became more external, reflecting a high correlation between their aggression and a stimulus tone. Results suggest that a person's increased aggressiveness when intoxicated results from an interaction between alcohol and an altered responsivity to provoking stimuli. (37 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
73.
The electrochemical properties of a novel composite paper material of high surface area consisting of polypyrrole (PPy) deposited on cellulose derived from Cladophora sp. algae have been investigated in electrolytes containing different concentrations of nitrate, chloride and p-toluene sulfonate, as well as in solutions containing both p-toluene sulfonate and chloride. The oxidation mechanism and the dependence of the oxidation behavior of the polypyrrole, which was obtained by oxidation of pyrrole with iron(III) chloride, on the anion type and concentration have been studied. Current nucleation maxima, appearing at different times depending on the anion concentration, were obtained during the oxidation of the reduced polymers as a result of the combined action of the formation and growth of conducting polymer strands and anion diffusion. No loss of capacity was seen during repeated oxidation and reduction of the polymer indicating that trapping of anions in the reduced polymer did not limit the electroactivity of the present material. The latter can be explained by the thin polymer layer present on the cellulose substrate. During the oxidation of the polymer, the anions most likely first cover most of the surface of the composite before diffusing into the bulk of the polymer. The estimated distance between these surface sites was also found to match the size of the anions. For electrolytes containing a mixture of anions, the oxidation charge depends on the concentration and size of the different anions.The combination of the thin polymer coating and the large specific surface area of the composite give rise to a high ion absorption capacity even for large anions. Hence, the investigated material should be well-suited for use in biotechnological applications involving, e.g., desalting and extraction of proteins and DNA from biological samples. 相似文献
74.
Bekaert B Cooper ML Green FR McNulty H Pentieva K Scott JM Molloy AM Rayman MP 《Molecular nutrition & food research》2008,52(11):1324-1333
The level of plasma total homocysteine (tHcy), long known to be B vitamin dependent, has recently been shown to be inversely associated with plasma selenium (Se) concentration in human subjects. We therefore, chose to investigate the interaction between Se, tHcy and B vitamins in a double-blind, placebo-controlled trial where 501 healthy UK elderly volunteers were randomly allocated to receive 100, 200, or 300 microg Se/day as high-Se-yeast, or placebo-yeast for 6 months. Plasma Se, tHcy, folate, vitamin B-12, pyridoxal-5'-phosphate (PLP) and its catabolite, 4-pyridoxic acid, were measured in all participants at baseline and in samples from the placebo, 100 and 300 microg Se/day groups, at follow-up. At baseline, Se was inversely correlated with tHcy but only in males (p < 0.001). Before supplementation, tHcy concentration was significantly lower in the highest compared to the lowest Se tertile in males (p < 0.05), and in females when folate concentrations were also in the top tertile (p < 0.05). The effect of folate, PLP and vitamin B-12 concentrations on plasma tHcy correlated with Se concentration at baseline. After 6 months of Se supplementation, only Se concentration had changed significantly. Supplementation with Se does not affect tHcy concentration in the UK elderly population. 相似文献
75.
Zdolec N Hadžiosmanović M Kozačinski L Cvrtila Z Filipović I Skrivanko M Leskovar K 《Meat science》2008,80(2):480-487
The influence of the bacteriocinogenic culture Lactobacillus sakei (105/g) and semi-purified bacteriocin mesenterocin Y (2560 AU/kg) on the safety and quality of traditional Croatian fermented sausages was investigated. The addition of Lb. sakei and/or mesenterocin Y reduced microbial counts (P < 0.05) in the final products. After 28 days of ripening, coagulase-negative cocci decreased 1.5–2.0 log, yeasts 1.2–1.4 log and enterococci 1.7–2.7 log. In the case of the addition of Lb. sakei, the lactic acid bacteria count was significantly (P < 0.05) higher at day 7 of ripening, and was accompanied by a lower pH and a higher amount of lactic acid (P < 0.05). In the final product the amount of acetic acid was significantly lower. More intensive proteolysis and an increase in ammonia content were found at the beginning of fermentation, and in the second phase of ripening in the control samples, respectively. The free fatty acid concentration was significantly lower during the entire ripening process compared to the control (P < 0.05). Semi-purified mesenterocin Y did not affect the sensory properties of the sausages, whilst the addition of Lb. sakei enhanced them. 相似文献
76.
Dr. Kristina Goncharenko Dr. Michele Mari Dr. Yves P. Auberson Brieuc Matagne 《ChemMedChem》2020,15(24):2359-2362
The European Federation for Medicinal Chemistry (EFMC) created the Young Scientists Network (YSN) to support early-career medicinal chemists and chemical biologists. By doing this, it addressed the rapid changes taking place in the scientific community and in our society, such as the rise of social media, the evolution of the gender balance in the scientific population, and educational needs. Creating the YSN was also a way to ensure that the next generation of scientists would contribute to shaping EFMC's strategy, while recognizing and addressing their needs. The YSN was set up as a very dynamic concept, and has now developed to the point where its impact is evident. The activities it promotes complement EFMC's community support and scientific opportunities, rejuvenating the Federation and preparing it for the future. It also provides opportunities for many brilliant young scientists, who do not hesitate to invest time and energy in supporting our community and shaping their own future. 相似文献
77.
78.
Darikha Kudasova Botagoz Mutaliyeva Kristina Vlahovi
ek-Kahlina Slaven Juri Marijan Marijan Svetlana V. Khalus Alexander V. Prosyanik Suzana egota Nikola pani Marko Vincekovi 《International journal of molecular sciences》2021,22(5)
A new copper complex, trans-diaqua-trans-bis [1-hydroxy-1,2-di (methoxycarbonyl) ethenato] copper (abbreviation Cu(II) complex), was synthesized and its plant growth regulation properties were investigated. The results show a sharp dependence of growth regulation activity of the Cu(II) complex on the type of culture and its concentration. New plant growth regulator accelerated the development of the corn root system (the increase in both length and weight) but showed a smaller effect on the development of the wheat and barley root systems. Stimulation of corn growth decreased with increasing Cu(II) complex concentration from 0.0001% to 0.01% (inhibition at high concentrations—0.01%). The development of corn stems was also accelerated but to a lesser extent. Chitosan-coated calcium alginate microcapsules suitable for delivery of Cu(II) complex to plants were prepared and characterized. Analysis of the FTIR spectrum showed that complex molecular interactions between functional groups of microcapsule constituents include mainly electrostatic interactions and hydrogen bonds. Microcapsules surface exhibits a soft granular surface structure with substructures consisting of abundant smaller particles with reduced surface roughness. Release profile analysis showed Fickian diffusion is the rate-controlling mechanism of Cu(II) complex releasing. The obtained results give new insights into the complexity of the interaction between the Cu(II) complex and microcapsule formulation constituents, which can be of great help in accelerating product development for the application in agriculture 相似文献
79.
Sauleh Eetemadi William Lewis Kristina Toutanova Hayder Radha 《Machine Translation》2015,29(3-4):189-223
Statistical machine translation has seen significant improvements in quality over the past several years. The single biggest factor in this improvement has been the accumulation of ever larger stores of data. We now find ourselves, however, the victims of our own success, in that it has become increasingly difficult to train on such large sets of data, due to limitations in memory, processing power, and ultimately, speed (i.e. data-to-models takes an inordinate amount of time). Moreover, the training data has a wide quality spectrum. A variety of methods for data cleaning and data selection have been developed to address these issues. Each of these methods employs a search or filtering algorithm to select a subset of the data, given a defined set of feature functions. In this paper we provide a comparative overview of research in this area based on application scenario, feature functions and search method. 相似文献
80.
Justina Mileriene Loreta Serniene Kristina Kondrotiene Lina Lauciene Neringa Kasetiene Dalia Sekmokiene Vaida Andruleviciute Mindaugas Malakauskas 《International Journal of Food Science & Technology》2021,56(6):2853-2863
Consumer interest in a healthy lifestyle and health-promoting natural products is a major driving force for the increasing global demand for bio-functional and sustainable dairy foods. Supplementation of curd cheese with thermo-coagulated acid whey protein (TAWP) led to 8–10% higher contents of moisture, 23–31% of lactose, 12–13% of unsaturated, 5–6% of monounsaturated, 63% of polyunsaturated, and 3–4% of long-chain fatty acids. Lipid quality indices – TI, AI, h/H, and Omega 6/3 among others, were also significantly better than those of control cheese. The addition of indigenous Lactococcus lactis strain enhanced the flavour of cheese samples, decreased the counts of yeast and mould up to 1 log cfu g−1 after 10 days of storage. The replacement of curd with TAWP resulted in novel cheese with overall sensory perception above 77 points and added nutritional and functional value, however, body and texture parameters of modified cheese samples require an improvement. 相似文献