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101.
102.
Liubov Shtykova Mariam Masuda Carina Eriksson Kristina Sjödin Elisabeth Marling Fredrik Schlyter Magnus Nydén 《Progress in Organic Coatings》2008
Latex-based coatings for protection of tree seedlings against pest insect feeding are evaluated with respect to surface-, mechanical-, and release properties and antifeedant activity. The latex dispersion Eudragit copolymer (EC) was used to form the coatings, 2,6-di-tert-butyl-4-methylphenol (BHT) and cis-dihydropinidine (Alk) as antifeedants, and a thickener and a alkylglucoside based nonionic surfactant were used as additives to optimize the release- and mechanical properties of coatings. Coating characterization was performed with respect to surface morphology (atomic force microscopy, AFM) and surface wetting (contact angle), as well as to mechanical (tensile stress- and tensile strain at break) properties. Surface smoothness and wettability as well as elasticity increased with addition of the surfactant. The optimized coatings were found to be elastic and water resistant at 3–6 wt.% of BHT and 3 wt.% of surfactant. BHT was released into SDS/water at very low rates. Several formulations of BHT and Alk were efficient in preventing the feeding on conifer bark by a pine insect, Hylobius abietis both in laboratory (no-choice) and in field (3 months) tests. 相似文献
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This paper presents a pilot study in which specific activities of 14C in hair and urine from 11 radiation workers handling 14C-containing substances have been measured using accelerator mass spectrometry. Varying degrees of contamination were revealed: up to 63% excess in hair and 400% excess in urine. Although the 14C excess reported in this study would result in low effective doses, it would be of interest to monitor the situation at other workplaces with potentially higher risks of contamination. Simultaneous measurements of 14C in hair and urine with additional random measurements of 14C in faeces and exhaled air could provide a means of improving dose estimates for workers handling different types of 14C-containing substances. 相似文献
105.
Tovilovic G Zogovic N Harhaji-Trajkovic L Misirkic-Marjanovic M Janjetovic K Vucicevic L Kostic-Rajacic S Schrattenholz A Isakovic A Soskic V Trajkovic V 《ChemMedChem》2012,7(3):495-508
The protective ability of novel arylpiperazine-based dopaminergic ligands against nitric oxide (NO)-mediated neurotoxicity is investigated. The most potent neuroprotective arylpiperazine identified during the study was N-{4-[2-(4-phenyl-piperazin-1-yl)ethyl]-phenyl}picolinamide, which protected SH-SY5Y human neuron-like cells from the proapoptotic effect of NO donor sodium nitroprusside (SNP) by decreasing oxidative stress, mitochondrial membrane depolarization, caspase activation and subsequent phosphatydilserine externalization/DNA fragmentation. The protective effect was associated with the inhibition of proapoptotic (JNK, ERK, AMPK) and activation of antiapoptotic (Akt) signaling pathways, in the absence of interference with intracellular NO accumulation. The neuroprotective action of arylpiperazines was shown to be independent of dopamine receptor binding, as it was not affected by the high-affinity D?/D? receptor blocker butaclamol. These results reported support the further study of arylpiperazines as potential neuroprotective agents. 相似文献
106.
Kristina RamanauskieneAda Stelmakiene Vitalis BriedisLiudas Ivanauskas Valdas Jakštas 《Food chemistry》2012,132(3):1544-1548
Different sorts of Lithuanian honey were analysed by quantitative determination of eight free phenolic acids and phenylpropanoid vanillin using high performance liquid chromatography (HPLC). Aqueous ethanol 60% was used as a solvent for preparation of honey samples. Amounts of phenolic acids honey solutions were in the range from 7.176 to 125.624 mg/ml. Free phenolic acids and vanillin had been detected in all samples of honey, but their composition and amount depended on its botanic origin. p-Coumaric and ferulic acids proved to be the main components in the acacia and buckwheat honey. Raspberry and polyfloral forest honey contained the highest amounts of chlorogenic acid. Gallic acid is a principal phenolic acid in eucalyptus honey. The highest amount of vanillin was identified in buckwheat honey. The results of the analysis revealed that free phenolic acids and vanillin were detected in all honey samples analysed, and their range and amounts varied. 相似文献
107.
The oxidation of lipids in different prefabricated meat products may have detrimental effects on the organoleptic properties and/or safety of meat, and poses a serious health concern. The oxidation processes may be accelerated by acids that are added to some products, e.g., marinated meat. In this work, the oxidation of free polyunsaturated fatty acids during pork marination in the presence of different acidifiers was investigated. It was demonstrated by the measurement of thiobarbituric acid reactive substances (TBARS) and by liquid chromatography - tandem mass spectroscopy that the highest degree of oxidation occurred in acetic acid and lactic acid marinades, whereas the oxidation was significantly suppressed by citric and ascorbic acids. Among the primary products of oxidation, 9,12,13-trihydroxy-10-octadecenoic acid and two isomers of hydroxy-epoxy-octadecenoic acid were dominating. A nearly linear correlation between TBARS values and total content of these two hydroxy-fatty acids was observed. 相似文献
108.
High levels of polybrominated dibenzo-p-dioxins (PBDDs) have been found in Baltic Sea biota, where the toxic load owing to, for example, polychlorinated dibenzo-p-dioxins and other organic pollutants is already high. The levels and geographic pattern of PBDDs suggest biogenic rather than anthropogenic origin, and both biotic and abiotic formation pathways have been proposed. Photochemical formation from hydroxylated polybrominated diphenyl ethers (OH-PBDE) is a proposed pathway for PBDDs in marine environments. Ultraviolet radiation-initiated transformations of OH-BDEs 47, 68, 85, 90, 99, and 123, which all are abundant in the environment, were investigated. It was shown that the most abundant PBDDs in the environment (1,3,7-triBDD and 1,3,8-triBDD) can be formed from the most abundant OH-BDEs (OH-BDE 47 and OH-BDE 68) at high rates and with percentage yields. In fact, most of the PBDDs that have been identified in the Baltic Sea environment were formed with high yield from the six studied OH-PBDE, through initial cyclization and subsequent debromination reactions. The high formation yields point to this route as an important source of PBDDs in biota. However, congeners showing relatively high retention in fish, specifically 1,3,6,8- and 1,3,7,9-tetraBDD, were not formed. These are likely formed by enzymatic coupling of brominated phenols. 相似文献
109.
Tomislav Mašek Luka Krstulović Diana Brozić Marina Vranić Maja Maurić Miroslav Bajić Kristina Starčević 《European Food Research and Technology》2014,238(4):635-640
The objective of the study was to explore whether it is possible to alter cow colostrum and early milk fatty acid composition with a low level of fat supplement, high in docosahexaenoic (DHA) and eicosapentaenoic (EPA) fatty acid. Diets included a control diet and a diet supplemented with DHA- and EPA-enriched fat supplement. Addition of fat supplement significantly decreased saturated fatty acids, C14:0 and C16:0 and increased the values of monounsaturated fatty acids, polyunsaturated fatty acids (PUFA), n3 fatty acids, EPA, DHA, C18:1n9cis and C18:1n11trans. The percentage of short-chain fatty acids significantly increased with the progress of lactation, while the percentage of PUFA, n3 and n6 significantly decreased. These results showed that fat supplement, high in DHA and EPA, modified the fatty acid profile of colostrum and milk fat and increased the proportion of beneficial fatty acids for human health. 相似文献
110.
Finke Kathrin; Schwarzkopf Wolfgang; Müller Ulrich; Frodl Thomas; Müller Hermann J.; Schneider Werner X.; Engel Rolf R.; Riedel Michael; M?ller Hans-Jürgen; Hennig-Fast Kristina 《Canadian Metallurgical Quarterly》2011,120(4):890
Attention deficit hyperactivity disorder (ADHD) persists frequently into adulthood. The decomposition of endophenotypes by means of experimental neuro-cognitive assessment has the potential to improve diagnostic assessment, evaluation of treatment response, and disentanglement of genetic and environmental influences. We assessed four parameters of attentional capacity and selectivity derived from simple psychophysical tasks (verbal report of briefly presented letter displays) and based on a “theory of visual attention.” These parameters are mathematically independent, quantitative measures, and previous studies have shown that they are highly sensitive for subtle attention deficits. Potential reductions of attentional capacity, that is, of perceptual processing speed and working memory storage capacity, were assessed with a whole report paradigm. Furthermore, possible pathologies of attentional selectivity, that is, selection of task-relevant information and bias in the spatial distribution of attention, were measured with a partial report paradigm. A group of 30 unmedicated adult ADHD patients and a group of 30 demographically matched healthy controls were tested. ADHD patients showed significant reductions of working memory storage capacity of a moderate to large effect size. Perceptual processing speed, task-based, and spatial selection were unaffected. The results imply a working memory deficit as an important source of behavioral impairments. The theory of visual attention parameter working memory storage capacity might constitute a quantifiable and testable endophenotype of ADHD. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献