Modello numerico di flusso e trasporto del sistema acquifero della pianura del Cecina (Toscana, Italia), con l'uso di elaborazioni GIS Groundwater Flow and Transport Model in Cecina Plain (Tuscany, Italy) using GIS processing

This work provides a groundwater flow and transport model of trichlorethylene and tetrachlorethylene contamination in the Cecina's coastal aquifer. The contamination analysis, with source located in the Poggio Gagliardo area (Montescudaio, Pisa), was necessary to optimize the groundwater monitoring and remediation design. The work was carried out in two phases: • design of a conceptual model of the aquifer using GIS analysis of many stratigraphic, chemical and hydrogeological data, collected from 2004 to 2012 in six aqueduct wells; • implementation of a groundwater flow and transport numerical model using the MODFLOW 88/96 and MT3D code and the graphical user interface GroundWaterVistas 5. The conceptual model hypothesizes a multilayer aquifer in the coastal plain extended to the sandy-clay hills, recharged by rainfall and by the Cecina River. The aquifer shows important hydrodynamic features affecting both the contamination spreading, due to the presence of a perched and heavily polluted layer separate from the underlying productive aquifer, and the hydrological balance, due to a thick separation layer that limits exchanges between the river and the second groundwater aquifer. The numerical model, built using increasingly complex versions of the initial conceptual model, has been calibrated using monitoring surveys conducted by the Environmental Protection Agency of Regione Toscana (ARPAT), in order to obtain possible forecast scenarios based on the minimum and maximum flow periods, and it is currently used as a tool for decision support regarding the reclamation and/or protection of the aquifer. Future developments will regard the implementation of the multilayer transport model, based on a new survey, and the final coupling with the regional hydrological model named MOBIDIC

Anisotropic straining of graphene using micropatterned SiN membranes

We use micro-Raman spectroscopy to study strain profiles in graphene monolayers suspended over SiN membranes micropatterned with holes of non-circular geometry. We show that a uniform differential pressure load $\Delta P$ over elliptical regions of free-standing graphene yields measurable deviations from hydrostatic strain conventionally observed in radially-symmetric microbubbles. The top hydrostatic strain $\bar{\varepsilon}$ we observe is estimated to be $\approx0.7\%$ for $\Delta P = 1\,{\rm bar}$ in graphene clamped to elliptical SiN holes with axis $40$ and $20\,{\rm \mu m}$. In the same configuration, we report a $G_\pm$ splitting of $10\,{\rm cm^{-1}}$ which is in good agreement with the calculated anisotropy $\Delta\varepsilon \approx 0.6\%$ for our device geometry. Our results are consistent with the most recent reports on the Gr\"uneisen parameters. Perspectives for the achievement of arbitrary strain configurations by designing suitable SiN holes and boundary clamping conditions are discussed.Comment: 8 pages, 6 figure (including SI

Catechol-Containing Hydroxylated Biomimetic 4-Thiaflavanes as Inhibitors of Amyloid Aggregation

The study of compounds able to interfere in various ways with amyloid aggregation is of paramount importance in amyloid research. Molecules characterized by a 4-thiaflavane skeleton have received great attention in chemical, medicinal, and pharmaceutical research. Such molecules, especially polyhydroxylated 4-thiaflavanes, can be considered as structural mimickers of several natural polyphenols that have been previously demonstrated to bind and impair amyloid fibril formation. In this work, we tested five different 4-thiaflavanes on the hen egg-white lysozyme (HEWL) amyloid model for their potential anti-amyloid properties. By combining a thioflavin T assay, atomic force microscopy, and a cell toxicity assay, we demonstrated that such compounds can impair the formation of high-order amyloid aggregates and mature fibrils. Despite this, the tested 4-thiaflavanes, although non-toxic per se, are not able to prevent amyloid toxicity on human neuroblastoma cells. Rather, they proved to block early aggregates in a stable, toxic conformation. Accordingly, 4-thiaflavanes can be proposed for further studies aimed at identifying blocking agents for the study of toxicity mechanisms of amyloid aggregation

An Efficient Catalytic Method for Regioselective Sulfenylation of Electron-rich Aza-aromatics at RoomTtemperature

Electron-rich aza-aromatic compounds such as indoles and pyrroles represent systems of particular interest and importance in organic chemistry. An useful methodology for regioselective direct introduction of sulfenyl group on electron-rich aza-aromatics through S-alkyl and S-arylthiophthalimides as sulfenylating agents is described. Catalytic amounts of CeCl3.7H2O-NaI system are crucial to the promotion of this regioselective carbon-sulfur bond-forming Friedel-Crafts reaction. The reaction occurred in mild conditions and the products were obtained in good to excellent yields. Due to the large importance of functionalized indoles among natural compounds and pharmaceutical products, the methodology represents an efficient preparation of sulfenyl aza-aromatics, which are useful intermediates for important organic transformations

Manuscrit de base et variantes de tradition dans le Chevalier de la charrette

Ces dernières décennies, les nouvelles technologies ont mis à la disposition des chercheurs une quantité considérable de ressources et de donnés. Pour le Conte de la Charrette de Chrétien de Troyes, ce progrès est dû principalement au Projet homonyme de Foulet et Uitti et à ses prolongements. Cependant, les nouveaux matériaux sont restés en marge des discussions de critique textuelle. Le débat autour du texte du roman de Chrétien s’est en effet polarisé sur la validité du texte transmis par la copie de Guiot (BNF, fr. 794) – employée pourtant comme manuscrit de base dans toutes les éditions les plus récentes. Nous proposons ici une approche différente du problème en vue de valoriser le riche patrimoine de variantes repérables dans la tradition manuscrite tout en préservant la lisibilité du roman. Nous soumettons donc à la réflexion une présentation du texte dans laquelle un commentaire de la varia lectio est relié à une « version de base ». Nous livrons cinq exemples pour lesquels nous croyons qu’une nouvelle évaluation de la varia lectio permet de mieux apprécier la richesse - en terme de lexique, de langue poétique, finalement de qualité littéraire - du texte de Chrétien.In the last decades, thanks to the development of new technologies, scholars have been provided with a large amount of digital resources and data. For Chrétien de Troyes’ Conte de la charrette, such an improvement is mainly due to the homonymous Project developed by Foulet and Uitti, and to its various continuations. However, such resources have had little impact on the discussion concerning textual criticism, in the context of the vivid debate about the Copie Guyot (BNF, fr. 794), the manuscrit-de-base (guide-manuscript) of all the recent editions of the roman. We propose to broach the problem in a new fashion, in order to highlight the rich heritage of variant readings of the manuscripts and to preserve the readability of the text. Therefore, the reader will find in this article a critical presentation of the text accompanied with a commentary on the varia lectio connected to the “base-version”. Such a purpose shall be exemplified with the study of five specific excerpts, the variant readings of which will be reassessed here. This enables us to shed a new light on the text by Chrétien de Troyes, from a lexical, linguistic and definitely literary point of view.Negli ultimi decenni, le nuove tecnologie hanno messo a disposizione diretta degli studiosi una grande quantità di risorse e di informazioni. Nel caso della Charrette di Chrétien de Troyes, questo progresso è essenzialmente dovuto al Projet omonimo ideato da Foulet e Uitti e alle sue varie filiazioni. Tuttavia, i nuovi materiali disponibili sono rimasti ai margini delle discussioni di critica testuale, e il dibattito sul testo del romanzo di Chrétien è parso sempre più polarizzarsi intorno alla difesa o critica puntuale del testo trasmesso dal manoscritto : di Guiot (BNF, fr. 794), utilizzato comunque come testo-base in tutte le edizioni recenti. Proponiamo qui una maniera diversa di affrontare il problema, che possa valorizzare il patrimonio di varianti presenti nella tradizione e al contempo preservare la leggibilità del romanzo. Sottoponiamo dunque alla riflessione una presentazione critica del testo in cui un commento della varia lectio è “innestato” su di una redazione-base. Esemplifichiamo il nostro intento attraverso cinque luoghi esemplari, per i quali crediamo che una nuova valutazione della varia lectio consenta di meglio cogliere la ricchezza – lessicale, linguistica e in definitiva letteraria – del testo di Chrétien

Resveratrol-based benzoselenophenes with an enhanced antioxidant and chain breaking capacity

The structural modification of the resveratrol scaffold is currently an active issue in the quest for more potent and versatile antioxidant derivatives for biomedical applications. Disclosed herein is an expedient and efficient entry to a novel class of resveratrol derivatives featuring an unprecedented 2-phenylbenzoselenophene skeleton. The new compounds were obtained in good yields by direct selenenylation of resveratrol with Se(0) and SO2Cl2 in dry THF. Varying the [Se:SO2Cl2:resveratrol] ratio resulted in the formation of the parent benzoselenophene (1) and/or mono (2) and/or dichloro (3) benzoselenophene derivatives. All the benzoselenophene derivatives proved to be more efficient than resveratrol in the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing/antioxidant power (FRAP) assays, with 1 showing an activity nearly comparable to that of Trolox. 1-3 also proved to be more efficient inhibitors than the parent resveratrol in kinetic experiments of styrene autoxidation. DFT calculations of the O-H bond dissociation enthalpy (BDE) revealed that the introduction of the Se-atom causes a significant decrease of the BDE of 3-OH and 5-OH, with just a small increase of the 4′-OH BDE. Compounds 1-3 showed no cytotoxicity at 5 μM concentrations on human keratinocyte (HaCaT) and intestinal (CaCo-2) cell line

Diabetes and acute bacterial skin and skin structure infections.

Acute bacterial skin and skin structures infections (ABSSSIs) are associated with high morbidity, costs and mortality in patients with diabetes mellitus. Their appropriate management should include several figures and a well-organized approach. This review aims to highlight the interplay between diabetes and ABSSSIs and bring out the unmet clinical needs in this area. Pathogenetic mechanisms underlying the increased risk of ABSSSIs in diabetes mellitus are multifactorial: high glucose levels play a crucial pathogenetic role in the tissue damage and delayed clinical cure. Moreover, the presence of diabetes complications (neuropathy, vasculopathy) further complicates the management of ABSSSIs in patients with diabetes. Multidrug resistance organisms should be considered in this population based on patient risk factors and local epidemiology and etiological diagnosis should be obtained whenever possible. Moreover, drug-drug interactions and drug-related adverse events (such as nephrotoxicity) should be considered in the choice of antibiotic therapy. Reducing unnecessary hospitalizations and prolonged length of hospital stay is of primary importance now, more than ever. To achieve these objectives, a better knowledge of the interplay between acute and chronic hyperglycemia, multidrug resistant etiology, and short and long-term outcome is needed. Of importance, a multidisciplinary approach is crucial to achieve full recovery of these patients