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141.
Silvio Mollo Gianluca Iezzi Guido Ventura Andrea Cavallo Piergiorgio Scarlato 《Journal of Non》2012,358(12-13):1624-1628
Pt-capsules loaded with a Pt-coil and two crystalline seeds immersed into an andesitic melt were rapidly cooled from 1300 to 1100 °C with a rate of 3 °C/min at atmospheric pressure and air oxygen fugacity. Results show that the Pt-coil does not induce any heterogeneous crystallization process as well as iron diffusion process from the melt into the platinum substrate. In contrast, the presence of crystalline seeds in a solidifying andesitic melt significantly alters the phase assemblage, composition and texture of the new-forming crystals in response to a heterogeneous nucleation mechanism and the formation of metastable phases. 相似文献
142.
Top-down patterning of zeolitic imidazolate framework composite thin films by deep X-ray lithography
Dimitrakakis C Marmiroli B Amenitsch H Malfatti L Innocenzi P Grenci G Vaccari L Hill AJ Ladewig BP Hill MR Falcaro P 《Chemical communications (Cambridge, England)》2012,48(60):7483-7485
For the first time a top-down process was used to control the spatial location of Metal-Organic Frameworks on a surface. Deep X-ray lithography was utilised to micropattern a Zeolitic Imidazolate Framework layer on a sol-gel surface, with exposure hardening the sol-gel by inducing crosslinking while leaving the frameworks intact. 相似文献
143.
144.
Carlo Scapolla Giuliana Cangemi Sebastiano Barco Laura Barbagallo Daniela Bugnone Angelo Maffia Giovanni Melioli Aldo Profumo Umberto Benatti Gianluca Damonte 《Journal of mass spectrometry : JMS》2012,47(7):816-824
The levels of urinary catecholamine metabolites, such as homovanillic acid (HVA) and vanillylmandelic acid, are routinely used as a clinical tool in the diagnosis and follow‐up of neuroblastoma (NB) patients. Recently, in the Clinical Pathology Laboratory Unit of G. Gaslini Children Hospital, a commercial method that employs liquid chromatography coupled to electrochemical detection (LC‐EC) has been introduced for the measurement of these metabolites in the routine laboratory practice. Using this LC‐EC method, an unknown peak could be observed only in samples derived from NB patients. To investigate the nature of this peak, we used a combination of liquid chromatography‐time‐of‐flight mass spectrometry (LC‐TOF‐MS) and liquid chromatography‐ion trap tandem mass spectrometry (LC‐IT‐MS). The first approach was used to obtain the elemental composition of the ions present in this new signal. To get additional structural information useful for the elucidation of unknown compounds, the ion trap analyzer was exploited. We were able to identify not just one, but three unknown signals in urine samples from NB patients which corresponded to three conjugated products of HVA: HVA sulfate and two glucuronoconjugate isomers. The enzymatic hydrolysis with β‐glucuronidase confirmed the proposed structures, while the selective alkaline hydrolysis allowed us to distinguish the difference between phenol‐ and acyl‐glucuronide of HVA. The latter was the unknown peak observed in LC‐EC separations of urine samples from NB patients. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
145.
Giorgio Colombo Gianluca Ottolina Giacomo Carrea 《Monatshefte für Chemie / Chemical Monthly》2000,131(6):527-547
Summary. In this article we review how molecular modeling techniques can be used to shed some light on the influence of organic solvents
on the molecular characteristics of proteins and enzymes. Molecular dynamic simulations on bovine pancreas trypsin inhibitor,
chymotrypsin, and subtilisin make it possible to get a deeper understanding into how increased intramolecular interactions
improve conformational rigidity, thus explaining the lower reactivity and the higher thermostability of enzymes in non-aqueous
media. The application of thermodynamics-based models allows first qualitative predictions on the selectivity of many reaction
types; however, the application of quantum mechanical/molecular mechanical methods is required for the development of quantitative
models of actual reactivity patterns.
Received November 18, 1999. Accepted (revised) February 8, 2000 相似文献
146.
Fuad O. Abdullah Faiq H. S. Hussain Abdullah Sh. Sardar Gianluca Gilardoni Solveig Tosi Giovanni Vidari 《Molecules (Basel, Switzerland)》2022,27(18)
Herbal medicines are still widely practiced in Kurdistan Region-Iraq, especially by people living in villages on mountainous regions. Among plants belonging to the genus Teucrium (family Lamiaceae), which are commonly employed in the Kurdish traditional medicine, we have analyzed, for the first time, the methanol and aqueous methanol extracts of T. parviflorum aerial parts. The plant is mainly used by Kurds to treat jaundice, liver disorders and stomachache. We aimed to determine the phytochemical profile of the extracts and the structures of the main components, so to provide a scientific rationale for the ancient use of the plant in the ethno-pharmacological field. TLC analysis of the two extracts on silica gel and reversed phase TLC plates, using different visualization systems, indicated similar contents and the presence of phenolics, flavonoids, terpenoids and sugars. The chlorophyll-free extracts exhibited weak/no antimicrobial activities against a panel of bacteria (MICs = 800–1600 µg/mL) and fungal strains (MICs ≥ 5 mg/mL). At the concentration of 600 µg/mL, the methanol extract showed moderate antiproliferative effects against A549 and MCF-7 cancer cell lines in the MTS assay. Moreover, both extracts exhibited a significant dose-dependent free radical scavenging action against the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical (EC50 = 62.11 and 44.25 μg/mL, respectively). In a phytochemical study, a high phenolic content (77.08 and 81.47 mg GAE/g dry extract, respectively) was found in both extracts by the Folin–Ciocalteu assay. Medium pressure liquid chromatographic (MPLC) separation of the methanol extract on a reversed phase cartridge eluted with a gradient of MeOH in H2O, afforded two bioactive iridoid glucosides, harpagide (1) and 8-O-acetylharpagide (2). The structures of 1 and 2 were established by spectral data, chemical reactions, and comparison with the literature. Interestingly, significant amounts of hepatotoxic furano neo-clerodane diterpenoids, commonly occurring in Teucrium species, were not detected in the extract. The wide range of biological activities reported in the literature for compounds 1 and 2 and the significant antiradical effects of the extracts give scientific support to the traditional use in Iraqi Kurdistan of T. parviflorum aerial parts for the preparation of herbal remedies. 相似文献
147.
Sara Liparoti Stefania Mottola Gianluca Viscusi Raffaella Belvedere Antonello Petrella Giuliana Gorrasi Roberto Pantani Iolanda De Marco 《Molecules (Basel, Switzerland)》2022,27(18)
The development of targeted therapies for wound repair is knowing a growing interest due to the increasing aging of the population and the incidence of chronic pathologies, mainly pressure ulcers. Among molecules recruiting cell populations and promoting the formation of new vital tissue, sodium mesoglycan (MSG) has been proven to be effective in wound healing. In this work, MSG impregnation of polymer matrices has been attempted by a supercritical carbon dioxide-based process. Polymeric matrices are composed of polycaprolactone blends, where water-soluble polymers, polyethylene glycol, polyvinyl pyrrolidone, gelatin, and thermoplastic starch, have been employed to modulate the MSG release, making the devices potentially suitable for topical administrations. Two different techniques have been used to obtain the films: the first one is compression molding, producing compact and continuous structures, and the second one is electrospinning, producing membrane-like designs. A higher amount of MSG can be loaded into the polymeric matrix in the membrane-like structures since, in these films, the impregnation process is faster than in the case of compression molded films, where the carbon dioxide has firstly diffused and then released the active molecule. The type of water-soluble polymer influences the drug release rate: the blend polycaprolactone-gelatin gives a prolonged release potentially suitable for topical administration. 相似文献
148.
Gianluca Bianchini Valentina Brombin Pasquale Carlino Enrico Mistri Claudio Natali Gian Marco Salani 《Molecules (Basel, Switzerland)》2021,26(7)
In the Adriatic lagoons of northern Italy, manila clam (Ruditapes philippinarum) farming provides important socio-economic returns and local clams should be registered with the Protected Designations of Origin scheme. Therefore, there is a need for the development of rapid, cost-effective tests to guarantee the origin of the product and to prevent potential fraud. In this work, an elemental analysis (EA) coupled with isotope ratio mass spectrometry (IRMS) was employed to identify the isotopic fingerprints of clams directly collected onsite in three Adriatic lagoons and bought at a local supermarket, where they exhibited certification. In particular, a multivariate analysis of C/N, δ13C and δ15N in manila clam tissues as well as δ13C in shells and 13C (calculated as δ13Cshell–δ13Ctissues) seems a promising approach for tracking the geographical origin of manila clams at the regional scale. 相似文献
149.
The use of catalytic methylrhenium trioxide (MTO) and urea hydrogen peroxide in room temperature ionic liquid for the hydroxyglycosylation with glycals in a domino fashion is reported. Excellent conversions and good selectivities for the epoxidation reaction were observed. Application to the synthesis of glycosylphosphates, good glycosyl donors, has been studied. 相似文献
150.
Gianluca Allemandi Monica Capone Salvatore Capozziello Mauro Francaviglia 《General Relativity and Gravitation》2006,38(1):33-60
The debate on the physical relevance of conformal transformations can be faced by taking the Palatini approach into account
gravitational theories. We show that conformal transformations are not only a mathematical tool to disentangle gravitational
and matter degrees of freedom (passing from the Jordan frame to the Einstein frame) but they acquire a physical meaning considering
the bi-metric structure of Palatini approach which allows to distinguish between spacetime structure and geodesic structure.
These facts are relevant at least at cosmological scales, while at small scale (i.e. in the spacetime regions relevant for
observations) the conformal factor is slowly varying and its effects are not relevant. Examples of higher-order and non-minimally
coupled theories are worked out and relevant cosmological solutions in Einstein frame and Jordan frame are discussed showing
that also the interpretation of cosmological observations can drastically change depending on the adopted frame. 相似文献