I teatri a Salerno prima del Verdi

94 p. : 10 p. di tav. ; 16 cm. ((Documento digitale nativoL’autore raccoglie e riordina una quantità notevole di materiale d’archivio, delineando il quadro complessivo delle rappresentazioni teatrali e musicali a Salerno a partire dalla metà del Settecento fino alla seconda metà dell’Ottocento. Le fonti di riferimento sono la Cronaca di Salerno (1709-1787) di Matteo Greco e i documenti del Fondo Intendenza, Teatri e Opere pubbliche dell’Archivio di Stato di Salerno. Una descrizione puntuale riguarda la scelta del sito dove costruire il nuovo teatro (denominato di San Gioacchino, e ribattezzato, dopo la caduta di Murat, di San Matteo), delle spese affrontate, dei fondi, dei contratti con gli impresari delle compagnie. Il contributo alterna nell’esposizione la forma narrativa a elementi di natura tecnica, passando in rassegna fatti e personaggi che si sono avvicendati nei decenni in questione: sindaci, deputati, ingegneri, artigiani, impresari, capocomici, artisti, custodi del teatro

Caracterização estratigráfica dos microbialitos da formação Wilberns (cambriano superior), município de Mason, Texas (EUA)

Durante o Cambriano superior, há aproximadamente 490 milhões de anos, a porção central do Estado do Texas, no sul dos Estados Unidos da América, estava completamente submersa e fazia parte da Grande Plataforma Carbonática Americana na margem oeste do paleocontinente Laurência que, nesse momento, encontrava-se em latitude equatorial. Os membros Point Peak e San Saba, topo da Formação Wilberns, registram um importante momento dessa prolífica fábrica carbonática do Paleozoico Inferior: a transição de uma sedimentação carbonática predominantemente autóctone, com a formação de biohermas, bioestromas, estromatólitos e trombólitos do Membro Point Peak, para uma sedimentação de caráter essencialmente clástica, com o desaparecimento dessas bioconstruções e geração de packstones e grainstones esqueletais do Membro San Saba. Sendo assim, além da descrição de aspectos gerais dessas unidades, o principal objetivo deste estudo é compreender as razões pelas quais os microbialitos pararam de se formar a partir do estudo morfológico das bioconstruções e da caracterização faciológica da unidade clástica. Para tal, seis afloramentos foram analisados e fotografados com auxílio de um drone, de modo a alcançar locais inacessíveis nas escarpas e permitir perspectivas de imagem 3D das exposições. Quatorze testemunhos com comprimento de aproximadamente 30 centímetros e 12 lâminas delgadas embasaram as descrições faciológica e morfológica. Como resultado, a análise da unidade de natureza autóctone (Mb. Point Peak) permitiu a individualização de três porções morfologicamente distintas em cada um dos biohermas e, estas foram interpretadas como fases de crescimento microbial (Fase 1, de “colonização”, Fase 2, de “agradação vertical” e “expansão lateral”, e a Fase 3, de “capeamento”) que são inibidas com a entrada de sedimentos siliciclásticos no sistema. Com a caracterização faciológica da unidade clástica sobreposta (Mb. San Saba) foram identificados organismos metazoários anteriormente escassos, principalmente gastrópodes e trilobitas, cuja presença pode ter aumentado a competição por recursos naturais, o que inibiu o desenvolvimento microbial e, consequentemente, a formação das bioconstruções. Sendo assim, o aumento da frequência desses metazoários sugere que o Mb. Point Peak está possivelmente inserido num contexto de período anacronístico, no qual os microbialitos se desenvolvem e florescem na ausência de metazoários competidores, sendo essa portanto, a principal razão do declínio microbial carbonático da Formação Wilberns

Charge Recombination Kinetics of Bacterial Photosynthetic Reaction Centres Reconstituted in Liposomes: Deterministic Versus Stochastic Approach

In this theoretical work, we analyse the kinetics of charge recombination reaction after a light excitation of the Reaction Centres extracted from the photosynthetic bacterium Rhodobacter sphaeroides and reconstituted in small unilamellar phospholipid vesicles. Due to the compartmentalized nature of liposomes, vesicles may exhibit a random distribution of both ubiquinone molecules and the Reaction Centre protein complexes that can produce significant differences on the local concentrations from the average expected values. Moreover, since the amount of reacting species is very low in compartmentalized lipid systems the stochastic approach is more suitable to unveil deviations of the average time behaviour of vesicles from the deterministic time evolution

α-cyclodextrin and α-cyclodextrin polymers as oxygen nanocarriers to limit hypoxia/reoxygenation injury: Implications from an in vitro model

The incidence of heart failure (HF) is increasing worldwide and myocardial infarction (MI), which follows ischemia and reperfusion (I/R), is often at the basis of HF development. Nanocarriers are interesting particles for their potential application in cardiovascular disease. Impaired drug delivery in ischemic disease is challenging. Cyclodextrin nanosponges (NS) can be considered innovative tools for improving oxygen delivery in a controlled manner. This study has developed new α-cyclodextrin-based formulations as oxygen nanocarriers such as native α-cyclodextrin (α-CD), branched α-cyclodextrin polymer (α-CD POLY), and α-cyclodextrin nanosponges (α-CD NS). The three different α-CD-based formulations were tested at 0.2, 2, and 20 µg/mL to ascertain their capability to reduce cell mortality during hypoxia and reoxygenation (H/R) in vitro protocols. H9c2, a cardiomyoblast cell line, was exposed to normoxia (20% oxygen) or hypoxia (5% CO2 and 95% N2). The different formulations, applied before hypoxia, induced a significant reduction in cell mortality (in a range of 15% to 30%) when compared to samples devoid of oxygen. Moreover, their application at the beginning of reoxygenation induced a considerable reduction in cell death (12% to 20%). α-CD NS showed a marked efficacy in controlled oxygenation, which suggests an interesting potential for future medical application of polymer systems for MI treatment

Diffusive propagation of cosmic rays from supernova remnants in the Galaxy. I: spectrum and chemical composition

In this paper we investigate the effect of stochasticity in the spatial and temporal distribution of supernova remnants on the spectrum and chemical composition of cosmic rays observed at Earth. The calculations are carried out for different choices of the diffusion coefficient D(E) experienced by cosmic rays during propagation in the Galaxy. In particular, at high energies we assume that D(E)\sim E^{\delta}, with $\delta=1/3$ and $\delta=0.6$ being the reference scenarios. The large scale distribution of supernova remnants in the Galaxy is modeled following the distribution of pulsars, with and without accounting for the spiral structure of the Galaxy. We find that the stochastic fluctuations induced by the spatial and temporal distribution of supernovae, together with the effect of spallation of nuclei, lead to mild but sensible violations of the simple, leaky-box-inspired rule that the spectrum observed at Earth is $N(E)\propto E^{-\alpha}$ with $\alpha=\gamma+\delta$, where $\gamma$ is the slope of the cosmic ray injection spectrum at the sources. Spallation of nuclei, even with the small rates appropriate for He, may account for slight differences in spectral slopes between different nuclei, providing a possible explanation for the recent CREAM observations. For $\delta=1/3$ we find that the slope of the proton and helium spectra are $\sim 2.67$ and $\sim 2.6$ respectively at energies above 1 TeV (to be compared with the measured values of $2.66\pm 0.02$ and $2.58\pm 0.02$). For $\delta=0.6$ the hardening of the He spectra is not observed. We also comment on the effect of time dependence of the escape of cosmic rays from supernova remnants, and of a possible clustering of the sources in superbubbles. In a second paper we will discuss the implications of these different scenarios for the anisotropy of cosmic rays.Comment: 28 pages, To appear in JCA

Astrophysical models for the origin of the positron "excess"

Over the last three years, several satellite and balloon observatories have suggested intriguing features in the cosmic ray lepton spectra. Most notably, the PAMELA satellite has suggested an "anomalous" rise with energy of the cosmic ray positron fraction. In this article, we summarize the global picture emerging from the data and recapitulate the main features of different types of explanations proposed. The perspectives in testing different scenarios as well as inferring some astrophysical diagnostics from current/near future experiments are also discussed.Comment: 15 pages (150 references), 2 figures: review article for a Topical Issue on Cosmic Rays, matches version appearing in Astroparticle Physic

Glycated ACE2 reduces anti-remodeling effects of renin-angiotensin system inhibition in human diabetic hearts

High glycated-hemoglobin (HbA1c) levels correlated with an elevated risk of adverse cardiovascular outcomes despite renin-angiotensin system (RAS) inhibition in type-2 diabetic (T2DM) patients with reduced ejection fraction. Using the routine biopsies of non-T2DM heart transplanted (HTX) in T2DM recipients, we evaluated whether the diabetic milieu modulates glycosylated ACE2 (GlycACE2) levels in cardiomyocytes, known to be affected by non-enzymatic glycosylation, and the relationship with glycemic control