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11.
The genus Thymus L. consists of many species of herbaceous perennials and sub-shrubs. A chemical characterisation of a collection of Thymus spp. originated from regions of Southern Italy was performed using GC and GC/MS. The accessions were collected from various natural habitats of the Basilicata and Puglia Regions and transferred into a new uniform environment. The study showed that amongst the 22 components of the oils the most recurrent ones were geraniol, thymol and α-terpinene followed by linalool, citral and trans-caryophillene. Cluster analysis led to the identification of two chemotypes: geraniol and thymol/α-terpinene; only a biotype remained separate from all others, probably because of its high content linalool (58%).  相似文献   
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Software and Systems Modeling - Mobile robots operate in various environments (e.g. aquatic, aerial, or terrestrial), they come in many diverse shapes and they are increasingly becoming parts of...  相似文献   
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Novel and potent inhibitors of Plasmodium falciparum plasmepsin II were identified by post‐processing the results of a docking screening with BEAR, a recently reported procedure for the refinement and rescoring of docked ligands in virtual screening. FRET substrate degradation assays performed on the 30 most promising compounds resulted in 26 inhibitors with IC50 values ranging from 4.3 nM to 1.8 μM .

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A series of 2-phenyloxazoles bearing an amide group at position 4 were designed and synthesized for evaluation as potential inhibitors of human recombinant monoamine oxidases (hrMAOs). Results of kinetics experiments demonstrated that all compounds behave as competitive MAO inhibitors, with good selectivity toward the MAO-B isoform. The most potent and selective derivatives are characterized by inhibition constant (Ki) values in the sub-micromolar range and a good selectivity index (Ki MAO-A/Ki MAO-B>50). Some derivatives were also found to be able to inhibit MAO activity in nerve growth factor (NGF)-differentiated PC12 cells, taken as a model of neuronal cells. In particular, 2-(2-hydroxyphenyl)-N-phenyloxazole-4-carboxamide (compound 4 a ) may be a promising new scaffold, exerting the highest selectivity and inhibitory effect toward MAOs in NGF-differentiated PC12 cell lysates, without compromising cell viability. Molecular docking analysis allowed a rationalization of the experimentally observed binding affinity and selectivity.  相似文献   
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Triacylglycerols (TAG) are the most important group of compounds present in vegetable oils. These biomolecules, determining the physical, chemical and nutritional properties of the oils, are considered to be good fingerprints for quality and authenticity control. Therefore, TAGs characterization is a very important task in edible oil field, which has been undertaken by different analytical methods. The analysis of vegetable oils is still dominated by classic determinations, which are however laborious and time‐consuming and cannot be used routinely. More recently, advances in MS instrumentations coupled with online separation techniques and data processing have contributed to great expansion of MS in oil study, allowing the development of innovative analytical approaches that exhibit higher sensitivity, accuracy and rapidity in vegetable oils investigations. In the present contribution, a review of the most relevant applications of novel mass spectrometric techniques, such as ESI and MALDI, both alone and hyphenated with HPLC, used for analysis of the complex TAGs mixture of edible oils is illustrated.  相似文献   
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Perfluorooctanoic acid (PFOA) and perfluorooctane sulphonate (PFOS) are environmental contaminants belonging to a chemical group known as perfluorinated compounds (PCFs). The United States Environmental Protection Agency (US EPA) considers both compounds to be carcinogenic. The goal of the present study was to evaluate the contamination levels of PFOS and PFOA in edible fish of the Mediterranean Sea. Twenty six fish muscles, 17 fish livers, five series of cephalopods (each composed of ten specimens) and thirteen series of bivalves (each composed of about 50 specimens) were used for the investigation. A fast sample treatment, followed by an LC–ESI–MS/MS method is described for the identification, and quantification of PFOA and PFOS in fish. The method was in-house-validated through the determination of precision, accuracy, specificity, calibration curve, decision limit (CCα), and detection capability (CCβ). The results showed PFOA and PFOS levels in fishes and molluscs lower than those reported for analogue matrices in different geographic areas. Therefore, our biomonitoring results did not show that the Mediterranean Sea had any particularly alarming pollution by PFCs, although it is located in a semi-closed basin with scarce water change. Nonetheless, a worrying element is that a few fish showed extremely high contamination by PFOA and PFOS. This finding needs further clarification in order to assess whether such unusual contamination is linked to “dot-like” pollutant release, which could explain the anomaly.  相似文献   
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Thermoplastic polyurethane (TPU) nanocomposites containing graphene and graphene nanoribbons were obtained by polymerizing 1,4-butanediol with two diisocyanates (namely, 1,6-hexane diisocyanate or isophorone diisocyanate), in which the nanofillers were previously dispersed. Raman spectroscopy and Transmission Electron Microscopy demonstrated the formation of few-layer graphene and graphene nanoribbons dispersed in the monomers. At variance to the methods commonly reported in literature, that used in this work consists of the direct exfoliation of graphite without any chemical manipulation. Apart from the obvious cost and ease advantages, the so-obtained graphene does not contain any carboxy or alkoxy groups formed during the exfoliation process, which, at variance, are typically present in the most commonly reported methods. This finding paves the way toward the large-scale production of graphene and its nanoribbons, which are considered even more interesting than graphene itself for many potential applications. The obtained nanocomposites show a peculiar thermal and rheological behavior due to the presence of the nanofillers and to their reinforcing or plasticizing effect exerted on the TPU matrices.  相似文献   
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