196,085 research outputs found
Storia di un borgo e della sua comunità. Nosedo tra Milano e Chiaravalle
No full textStoria del borgo di Nosedo alla luce delle indagini archeologiche svolte all'interno della chiesa dei Santi Filippo e Giacom
Alimenti OGM e fitoterapia
No full textNaturale vs Artificiale; breve sotria dell'agricoltura; I vantaggi degli OGM; gli svantaggi degli OGM; il biopharming; Necessità di consapevolezza. La Fitoterapia; I fitoterapici; Piante ad azione adattogena: Ginseng, Eleuterococco, Rodiola e Witania. Il papavero della california
Le tecniche costruttive della casa medievale: analisi preliminare
No full textLe tecniche costruttive rinvenute nella casa medievale deurante la campagna di scavo del 201
Interazione tra architettura storica e paesaggio: ricostruire le tracce di una comunità
No full textIl paesaggio come esito di una serie di processi concatenati, che ne determinano l’aspetto che noi oggi conosciamo, è il risultato di azioni antropiche che ne hanno determinato la pluristratificazione. Nel rapporto tra uomo e ambiente si inserisce anche l’architettura come elemento di trasformazione, che diventa persistente e quindi traccia concreta dell’interazione tra i due. La lettura del paesaggio costruito, quindi, risulta fondante per riconoscere i segni dell’uomo nel territorio, e attraverso la distinzione di elementi diagnostici, mira a ricostruire il contesto nel quale si formano le comunità.
Lo studio del paesaggio storico, partendo dal costruito, viene declinato indagando le relazioni tra uomo, materia e ambiente, definendo una conoscenza che si basa sulla cultura materiale ed utilizzando gli edifici come documento di studio. Tale approccio può essere innovativo nell’ambito delle azioni di tutela dell’archeologica preventiva, fornendo una posizione innovativa al ruolo dell’archeologo dell’architettura
Metal ions interaction in Nicotiana plant tissue cultures: biochemical and molecular approaches
No full textThe metal resistance in plants is determined by specific physiological mechanisms which allow the plants to carry out their normal functional roles even in the presence of toxic metals at high concentration. The molecular basis of metal tolerance is not well understood and different physiological mechanisms have been suggested. This study examines the changes occurring in the gene expression induced by different metal ion stresses on the in vitro test system of Nicotiana glauca. Pith tissues, treated and no-treated, at different culture times after the explant, with different concentrations of Cd, Cu and Hg ions, have been analysed by biochemical and molecular techniques in order to individuate genes activated by ion treatments and possibly involved in metal stress tolerance. Biochemical results have shown variations in the synthetic activity of total protein extracts from control and treated tissues. Metal ion treatments specifically modulate protein synthesis. At molecular level, differential cDNA libraries from treated and control tissues evidenced specific genes activation. Metallothioneins (MTs) are cysteine-rich low molecular weight proteins that are able to bind metal ions. Their role in metal homeostasis/detoxification is well known, while in plants it is still a matter of discussion. Conserved regions of five MT-like genes (NgMT) were amplified, cloned and sequenced. The NgMTs expression was studies in control and in in vitro treated cultured pith tissues. The results showed that NgMT genes are expressed both in control and treated tissues: but interestingly, a NgMT clone is present only in the 100 mM Cu treated tissue
Desensitization of neuronal nicotinic receptors of human neuroblastoma SH-SY5Y cells during short or long exposure to nicotine
No full text1 Neuronal nicotinic ACh receptors (nAChRs) readily desensitize in the presence of an agonist. However, when the agonist is applied for minutes, hours or days, it is unclear how extensive desensitization is, how long it persists after agonist removal and whether nAChRs consequently change their pharmacological properties.
2 These issues were explored with electrophysiological studies of native receptors of voltage-clamped human neuroblastoma SH-SY5Y cells. Puffer pulses of nicotine (1mM)-evoked inward currents partly antagonized by methyllycaconitine (MLA; 10nM) or alpha-conotoxin MII ( MII; 10nM), suggesting contribution by alpha 7 and alpha 3 subunit containing receptors, respectively. Nicotine-evoked currents desensitized with 150ms time constant and fully recovered after a few s washout.
3 Although the current induced by 10min application of nicotine (10 mu M) decayed to baseline indicating complete desensitization, puffer applications of maximally effective doses of nicotine still generated small responses (22% of control). Similar responses to puffer-applied nicotine were observed when nicotine was chronically incubated for 8 or 48 h. On nicotine washout, cells recovered their response amplitude within 5 min and then increased it (about 50% of untreated controls) after 30 min without altering response kinetics or sensitivity to MLA and MII.
4 The present results suggest that native nAChRs of SH-SY5Y cells preserved a degree of responsiveness during chronic application of nicotine, and that they rapidly recovered on washout to generate larger responses without changes in kinetics or pharmacology. These data indicate strong compensatory mechanisms to retain nicotinic receptor function during long-term exposure to nicotine
Fragility functions for low-damage post-tensioned timber frames
No full textThe growing concern over environmental impact and the significant improvement in the quality of engineered wood products have led to the rapid growth of the timber building industry in the last decades. Although traditional, yet recent, mass timber structural systems, such as cross-laminated timber walls, can provide satisfactory seismic performance during earthquakes in terms of life-safety, the crucial need for more resilient timber buildings has prompted the development of low-damage high-performance self-centring and dissipative solutions based on unbonded post-tensioned hybrid connections, referred to as Pres-Lam technology. The flexibility of design and construction speed, combined with the enhanced seismic performance, create a unique potential towards an earthquake-proof sustainable building system. Despite the growing popularity of the technology, a comprehensive framework for the fragility analysis, to be used in risk and loss modelling applications, has not yet been developed for both component and building levels.This article aims to develop a framework for assessing the fragility curves of moment-resisting Pres-Lam frame systems, at both structural system and connection levels, by using and comparing different approaches that involve nonlinear static (pushover) and time history dynamic analyses. A Python-based parametric workflow was developed to evaluate fragility curves for a wide range of case-study buildings. Particularly, three distinct structures were selected, and their fragility curves were evaluated utilizing alternative methodologies at a building structural-system level. Finally, fragility models were fitted for individual structural connections using the results of time-history analyses. These models are intended for use in a component-based loss assessment
Archeologia e antropologia nella chiesa dei Santi Giacomo e Filippo a Nosedo
No full textrisultati delle indagini archeologiche nella chiesa dei SS. Filippo e Giacomo a Nosed
Reduction of the NO+ ligand in half-sandwich ruthenium derivatives
No full textThe reduction of the tetrafluoroborate salts of the ruthenium nitrosyl dicationic [Ru(η5-C5R5) (NO)(L)2]2+ (R=Me, L=PMe3, 1a; PMe2Ph, 1b; R=H, L=PPh3, 2d) and monocationic complexes [Ru(Me)Cp*(NO)L]+ (L=PMe3, 3a; PMe2Ph, 3b (Cpz.ast;=η5- C5Me5) has been studied by electrochemical and spectroscopic (IR, NMR, EPR) techniques. The nitrosyl complexes 1a, 1b and 2d exhibit two successive one-electron cathodic processes due to the sequential reduction of coordinated NO+ to NO and NO-, respectively. Chemical reduction yields products of rearrangement of the intermediates which have been spectroscopically characterized. EPR studies and theoretical calculations show that in the first one-electron reduction product the electron interacts with the NO nitrogen atom and that the RuNO moiety presents significant distortion from linearity. The X-ray structure of the related [Ir(Me)2Cpz.ast;(NO)]BF4 has been determined
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