117,553 research outputs found
Long-term treatment of duodenal ulcer with pirenzepine; gastric pH values and incidence of relapses: an open pilot study
No full textTwenty-three endoscopically healed duodenal ulcer patients entered a long-term treatment with pirenzepine for 1 year (two 25-mg tablets at breakfast and two tablets at bedtime). One day before and 7 days after the long-term treatment started, gastric pH and BAO were measured in each patient after fasting. The patients were clinically examined monthly and underwent endoscopy 4, 8 and 12 months after the trial started or when they complained of ulcer symptoms. Blood and urine laboratory tests were carried out before treatment began and 6 and 12 months afterwards. Eighteen of the 22 patients that completed the trial (82%) did not relapse. The statistical analysis tended to show a relationship between absence of pH increase and relapses. No severe side-effects or changes in the results of laboratory tests were observed
Prima del teatro: le prigioni, la sala del Consiglio e il fronte del Palazzo Pubblico sulla piazza del Mercato
No full textI recenti lavori di restauro del Teatro dei Rinnovati, a Siena, hanno offerto l’occasione per indagare a fondo, per la prima volta, l’intero settore del Palazzo Pubblico che dalla metà del Cinquecento ospita il ‘salone delle commedie’(circa un quarto dell’intero edificio). Il presente contributo espone i risultati delle indagini inerenti le strutture anteriori alla trasformazione in teatro, ricostruendo l’evoluzione del cantiere trecentesco.
Il primo nucleo, adibito a carceri pubbliche, fu realizzato tra il 1327 e il 1331 e dovette consistere in due piani voltati a botte, ancora esistenti, aventi lo stesso sviluppo longitudinale del corpo attuale ma con il fronte sulla piazza del mercato arretrato di quasi cinque metri. L’edificio, non ancora integrato con il Palazzo Pubblico, doveva inoltre presentarsi isolato su tutti i fronti compreso quello settentrionale, oggi collegato al palazzo stesso.
Pochi anni dopo una nuova fase costruttiva cambiò radicalmente l’aspetto e la volumetria dell’edificio originario. Nel 1339 fu infatti deciso di realizzare, al di sopra delle carceri, una nuova sala per le riunioni del consiglio generale e di integrare il nuovo volume con quello del palazzo comunale. Il corpo originario fu soprelevato di altri due piani, fino all’attuale altezza, e fu ampliato verso la piazza di quasi cinque metri assumendo l’aspetto che ancora oggi almeno in parte presenta, con forme, materiali e finiture analoghe a quelle degli altri fronti del Palazzo Pubblico.
Il ritrovamento, in corrispondenza del palco reale del teatro, dei resti del monumentale portale di accesso alla sala del consiglio, è risultato di fondamentale importanza per la ricostruzione dell’assetto trecentesco e del sistema di collegamento con il resto del palazzo. Questo infatti doveva avvenire per mezzo di un ponte sostenuto da volte e archi ribassati di undici metri di diametro, ancora oggi esistenti sebbene nascosti da più recenti strutture. Per mezzo di una scala il ponte collegava il cortile del Podestà, al quale si accede direttamente dalla piazza del Campo, con il secondo piano del nuovo edificio, interamente adibito a sala del consiglio.
La nuova struttura andò ad occultare una significativa porzione del fronte del Palazzo Pubblico rivolto sulla piazza del Mercato, concluso appena un decennio prima, impedendone così una visione unitaria. Ma l’eccezionale ritrovamento, al di sotto di intonaci moderni, di quattro dei dodici portali che in origine ne scandivano il fronte, per giunta in ottimo stato di conservazione, ha permesso di ricostruire l’aspetto dell’intero prospetto così come doveva presentarsi prima dell’edificazione della sala del consiglio, in un inedito e per certi aspetti sorprendente assetto compositivo, quale risultato di un disegno coerente con le forme dispiegate sul Campo e al tempo stesso portatore di un’autonoma visione
Detection of winterkill events of white mustard (Sinapis alba L.) by satellite-based remote sensing
No full textCover crop management mainly consists of sowing and termination, whose timing affects
the agro-ecological services provided by cover crops. Thus, identifying the correct time
windows is crucial for field management. Autumn-winter cover crops can be terminated
by frost damage (winterkill termination) if they are exposed to sub-zero temperatures
exceeding their frost tolerance. Assessing winterkill occurrence frequencies allows
comparing scenarios of crop management options for farms or regions, thus supporting the informed choice of cover crop species and sowing dates. A few studies regarding
cover crop species (Sinapis alba L. specifically) frost tolerance are reported in the literature and those present consisted of local indications. Satellite-based remote sensing is
suited for the estimation of the effects of biotic and abiotic crop stressors from field to
regional scales. However, a few studies addressed the monitoring of frost damage and
none of them on cover crops. The study aimed to develop a relationship between seven
different vegetation indices values and winterkill occurrence. A remote sensing monitoring campaign was carried out, using satellite images retrieved from Sentinel-2, during
the 2021-2022 autumn-winter season in six commercial farm fields of the Lombardy
region. Field measurements of aboveground biomass and visual assessment of frost
damage symptoms were performed to validate satellite data. Significant (p < 0.05) relationships were detected between the ground-measured frost damage index and the
vegetation indices (following She et al., 2015): EVI (R2 = 0.65), MSR (R2 = 0.67), NDRE
(R2 = 0.57). Furthermore, the procedure developed by Zhao et al. (2020) was adapted to
identify the timeframes during which a decrease of the vegetation index value can be
accounted for a frost damage event. The timeframes obtained through this procedure
were consistent with field observation opening the possibility of using satellite images
to support the field management of autumn-winter cover crops on a regional scale
Studio termomeccanico di un sistema di accumulo termico a sali fusi e di generazione di vapore. Relazione sulla 4° subattività: Studio delle prestazioni in condizioni di off-design dell’impianto a ciclo combinato di Priolo Gargallo integrato con il generatore di vapore a sali fusi. Report tecnico contratto tra Dipartimento di Energetica “L. Poggi” e ENEL Produzione-Ricerca nell’ambito del “Progetto Archimede” da 30 MWe
No full textGrowth, peroxidase activity and cytological modifications in Pisum sativum seedlings exposed to Ni2+ toxicity.
No full textNi2+ accumulation and the toxic effects of Ni2+ On growth were investigated in pea seedlings. In roots, Ni2+ absorption increased as a function of metal supply, while in the shoots the accumulation of the metal was restricted, particularly with higher treatments. Ten mu mol/L Ni2+ was found to be the lowest effective concentration to cause a significant reduction in root growth. Ni2+ did not induce changes in shoot length, even though biomass production was affected in both roots and shoots. The toxic effects of Ni2+ on K+ uptake and on water content were markedly higher in roots than in shoots. In the Ni-treated roots, these effects, and the concomitant increase in phenol content and extracellular peroxidase activity with affinity towards syringaldazine, were associated with an early induced cellular differentiation. The significance of this senescent-like slate, together with other cellular defence mechanisms such as the stimulation of intracellular peroxidase activity, is discussed in relation to Ni-stress
Nickel toxicity and peroxidase activity in seedlings of Triticum aestivum L.
No full textNi2+ toxicity was evaluated in Triticum aestivum L. by its effects on root and shoot length, dry matter production and water content. Over a threshold value of 20 mmol m 3 Ni2+ the degree of toxicity increases as a function of the Ni2+ concentration in the medium. Ni2+-treated roots show enhanced lipid peroxidation; the higher Ni2+ treatment (40mmol m 3) also increases leakage of K+. In roots and shoots, Ni2+ enhances both guaiacol and syringaldazine extracellular peroxidase activity. The increase in extracellular peroxidase activity is also associated with an increase in the phenolic contents of roots and shoots. The observed growth inhibition might be partly the result of the effect of Ni2+ on cell turgor and cell-wall extensibility. Intracellular soluble peroxidases are also stimulated by Ni2+; such effects, independently of the substrate, were detected in extracts of Ni2+-treated shoots at a lower Ni2+ concentration than in the roots. Intracellular peroxidases might act as scavengers of peroxide radicals produced as a result of nickel toxicity
Studio termomeccanico di un sistema di accumulo termico a sali fusi e di generazione di vapore. Relazione sulla 3° subattività: Layout dell’impianto solare e delle tubazioni. Report tecnico contratto tra Dipartimento di Energetica “L. Poggi” e ENEL Produzione-Ricerca nell’ambito del “Progetto Archimede” da 30 MWe
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