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Charles A. White John F. Kennedy Anna Lombard Valeria Rossetti 《Polymer International》1985,17(4):327-329
The oligosaccharide component compositions of a series of non-reducing oligosaccharides extracted from the roots of Arnica montana L. has been determined by gel permeation chromatography (g.p.c.). The range of oligosaccharides present was found to extend beyond the octasaccharide previously reported. with 16% to 19% of the oligosaccharides having a degree of polymerisation of between 11 and 19 and almost 3% having a degree of polymerisation greater than 20. The chromatographic behaviour of this series of oligosaccharides is compared with that observed for series of D-gluco-oligosaccharides. 相似文献
3.
Giovannetti Antonio Susi Gianluca Casti Paola Mencattini Arianna Pusil Sandra López María Eugenia Di Natale Corrado Martinelli Eugenio 《Neural computing & applications》2021,33(21):14651-14667
Neural Computing and Applications - In this paper, we present the novel Deep-MEG approach in which image-based representations of magnetoencephalography (MEG) data are combined with ensemble... 相似文献
4.
A kinetic analysis of the isothermal nitridation of high-purity oxide-free silicon powder is described. The kinetic analysis suggests that the and polymorphs of Si3N4 are formed by separate and parallel reaction paths. This analysis provides for the decoupling and quantitative kinetic interpretation of- and-Si3N4 formation reactions. Consistent with existing microstructural and thermodynamic evidence, the-forming reaction is shown to obey a first-order rate law, whereas a phase-boundary controlled rate law describes the-forming reaction. A kinetic model employing these rate laws is developed and is used to predict the/ phase ratio as a function of isothermal reaction temperature and extent of reaction. The/ phase ratios so obtained are shown to be in good agreement with experimental observations made under a variety of reaction conditions. 相似文献
5.
Mollie B. Schear Arianna Neal Jadah S. Clarke Andrew P. Saab Carl B. Giller Riccardo Casalini Matthew Laskoski 《应用聚合物科学杂志》2021,138(12):50053
The preparation of highly aromatic elastomers from a bisphenol A-based divinyl-terminated resin and polymerization with various aromatic silane containing compounds utilizing a room temperature hydrosilylation reaction is demonstrated. The polymers exhibit high thermal and oxidative stability with 5% weight losses around 430 and 350°C and char yields ranging from 35% to 40%. The thermosets maintained their elastomeric properties with good hardness and mechanical properties as measured by elongation measurements. The toughness of the thermosets was not improved with the inclusion of aromatic moieties but the hardness did appear to increase with the addition of more aromatic groups. 相似文献
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Cellular communication and the transfer of information from one cell to another is crucial for cell viability and homeostasis. During the last decade, tunneling nanotubes (TNTs) have attracted scientific attention, not only as a means of direct intercellular communication, but also as a possible system to transport biological cargo between distant cells. Peculiar TNT characteristics make them both able to increase cellular survival capacities, as well as a potential target of neurodegenerative disease progression. Despite TNT formation having been documented in a number of cell types, the exact mechanisms triggering their formation are still not completely known. In this review, we will summarize and highlight those studies focusing on TNT formation in the nervous system, as well as their role in neurodegenerative diseases. Moreover, we aim to stress some possible mechanisms and important proteins probably involved in TNT formation in the nervous system. 相似文献
8.
Arianna Manini Antonia Ratti Alberto Brusati Alessio Maranzano Isabella Fogh Silvia Peverelli Stefano Messina Davide Gentilini Federico Verde Barbara Poletti Claudia Morelli Vincenzo Silani Nicola Ticozzi 《International journal of molecular sciences》2022,23(16)
The transmembrane protein 106B (TMEM106B) gene is a susceptibility factor and disease modifier of frontotemporal dementia, but few studies have investigated its role in amyotrophic lateral sclerosis. The aim of this work was to assess the impact of the TMEM106B rs1990622 (A–major risk allele; G–minor allele) on phenotypic variability of 865 patients with amyotrophic lateral sclerosis. Demographic and clinical features were compared according to genotypes by additive, dominant, and recessive genetic models. Bulbar onset was overrepresented among carriers of the AA risk genotype, together with enhanced upper motor neuron involvement and poorer functional status in patients harboring at least one major risk allele (A). In a subset of 195 patients, we found that the homozygotes for the minor allele (GG) showed lower scores at the Edinburgh Cognitive and Behavioral Amyotrophic Lateral Sclerosis Screen, indicating a more severe cognitive impairment, mainly involving the amyotrophic lateral sclerosis-specific cognitive functions and memory. Moreover, lower motor neuron burden predominated among patients with at least one minor allele (G). Overall, we found that TMEM106B is a disease modifier of amyotrophic lateral sclerosis, whose phenotypic effects encompass both sites of onset and functional status (major risk allele), motor functions (both major risk and minor alleles), and cognition (minor allele). 相似文献
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Tullia Gallina Toschi Arianna Costa Giovanni Lercker 《Journal of the American Oil Chemists' Society》1997,74(4):387-391
Chromatographic techniques were used to separate secondary products generated by thermal degradation of methyl linoleate hydroperoxides
(MLHP). The MLHP were obtained by oxidation, selected, and concentrated by solid-phase extraction (SPE) and thin-layer chromatography
(TLC). The purified MLHP were then thermo-degraded in the gas-chromatographic glass liner and analyzed on-line by gas chromatography-mass
spectrometry (GC-MS). The MLHP were also thermodegraded and collected in a short silicic acid-packed column, eluted, separated
by TLC, and then analyzed by GC. By considering the elution in TLC, the GC retention times and the GC-MS analyses, it was
possible to characterize the mono- and the dioxygenated secondary products, particularly those having a boiling point higher
than methyl linoleate. The peaks that corresponded to the mono-oxygenated products (epoxy, hydroxy, and keto) were identified,
and, on the basis of their MS spectra, molecular structures were proposed. A specific elution order was suggested for keto
derivatives: 9-keto,Δ10,12- and 13-keto,Δ9,11-octadecadienoate. The hydroxy derivatives, which show the typical fragmentations of 9-hydroxy,Δ10,12- and 13-hydroxy,Δ9,11-octadecadienoate, were also identified. On the other hand, identification of the di-oxygenated compounds was more difficult,
and, therefore, it was not possible to indicate each positional isomer; however, their elution order could be epoxy-hydroxy
and epoxy-keto derivatives. 相似文献