63 research outputs found
è nostra. L’energia La democrazia energetica passa sia attraverso l’autonomia, sia dalla nascita di nuovi soggetti: dal basso
No full textEffect of Binarity in Star Cluster Dynamical Mass Determination
Get PDFIn this paper we explore the effects that the presence of a fraction of binary stars has in the determination of a star cluster mass via the virial theorem. To reach this aim in an accurate and consistent way, we run a set of simulations using the direct summation, high precision, code NBODY7. By means of this suite of simulations we are able to quantify the overestimate of open-star-cluster-like models' dynamical masses when making a straight application of the virial theorem using available position and radial velocity measurements. The mass inflation caused by the binary "heating" contribution to the measured velocity dispersion depends, of course, on the initial binary fraction, fb0 and its following dynamical evolution. For an fb (evolved up to 1.5 Gyr) in the range 8%-42% the overestimate of the mass done using experimentally sounding estimates for the velocity dispersion can be up to a factor of 45. We provide a useful fitting formula to correct the dynamical mass determination for the presence of binaries, and underline how neglecting the role of binaries in stellar systems might lead to erroneous conclusions about their total mass budget. If this trend remains valid for larger systems like dwarf spheroidal galaxies, which are still far out of reach for high-precision dynamical simulations taking their binaries into account, it would imply an incorrect overestimation of their dark matter content, as inferred by means of available velocity dispersion measurements
La vocazione teatrale di Alessandro Carli. Un tentativo di riforma delle scene nella Verona del secondo Settecento.
No full textNella tesi si esplora la personalità artistica del tragediografo veronese Alessandro Carli (1740-1814), esaminandola nel complesso della sua attività teatrale, analizzata sia sul piano della drammaturgia che su quello dell’allestimento scenico. Una volta inquadrata la situazione specifica dell’ambiente teatrale veneto tardosettecentesco, tra le istanze di cambiamento successive alla riforma goldoniana e l’influenza della cultura francese, vengono vagliate la composizione e le rappresentazioni delle tragedie "Telane ed Ermelinda", "I Longobardi" e "Ariàrato", nonché i riscontri di pubblico che conseguono. La ricerca mette in luce il progetto di rinnovamento perseguito dall’autore veronese, fondato, da un lato, sulla particolare attenzione dedicata al momento performativo (che si esplica tra le recite di nobili dilettanti e la messa in scena delle compagnie professionali), dall’altro, sulla necessità di una seria formazione attoriale, da affidare alla figura di un maestro di recitazione in grado di assumere anche funzioni di coordinamento.In this thesis is explored the artistic personality of Alessandro Carli (1740-1814), a playwright of tragedies from Verona. His work is examined both from dramaturgical and scenical point of view. Once investigated the specific theatrical context of Veneto in the late Eighteenth century (a context separated between the changing issues coming from the Goldonian reform and the influences of French culture), we analyse the writing structure and some representations of the three tragedies written by Carli ("Telane ed Ermelinda", "I Longobardi" and "Ariàrato"), and the success they gained on the stage. Our study enlightens the project of reform carried out by the Veronesian author: on one side, his project is based on the special attention given to the performing practice (caught between theatrical stagings by noble amateurs or by professional comedians), on the other, on the necessity to form new actors, guided by an acting master, who should also directed them on the stage
Evolutionary population synthesis and the Magellanic Clouds clusters
No full textSynthetic bolometric luminosities and U, B, V fluxes are computed for models of globular clusters using available stellar evolutionary tracks for two chemical compositions and for a large interval of age. The author presents some results and considerations relative to the study of some characteristics of the Magellanic Clouds globular clusters
Patients with PTSD after intensive care avoid hospital contact at 2-year follow-up
No full textPatients withPost-traumatic Stress Disorderafter intensive care avoid hospital contact at 2-year follow-u
The β-blocker propranolol affects cAMP-dependent signaling and induces the stress response in Mediterranean mussels, Mytilus galloprovincialis
No full textWidespread occurrence of pharmaceuticals is reported in aquatic systems, posing concerns for the health of aquatic wildlife and a theoretical risk to humans. A recent concept was developed for the identification of highly active compounds amongst the environmental pharmaceuticals, based on their mode of action, the homology between human targets and possible targets in the environment, and the importance of the affected pathway for the target species. In line with this approach, this study investigated whether propranolol (PROP) affects the cAMP-dependent pathway in Mediterranean mussels, Mytilus galloprovincialis. PROP is a prototypical β-adrenoceptor antagonist, and these receptors exist in bivalves and show gross pharmacological properties similar to their mammalian counterparts. PROP also acts as a 5-HT1 receptor antagonist, which is the sole 5-HT receptor reported in bivalves to date. Importantly, β-adrenoceptor and 5HT-1 receptor subtypes are positively and negatively coupled to cAMP-mediated signaling, respectively. PROP was administered as either l-PROP or dl-PROP. A wide range of concentrations was tested including low (0.3, 3 and 30ng/L) and high (300ng/L) environmental ranges, and a concentration 5-fold above the maximum reported environmental level (30,000ng/L). After a 7-day exposure, mussel cAMP levels and PKA activities were significantly reduced in digestive gland, increased in mantle/gonads and unaffected in gills. Similar patterns were observed for the mRNA expression of the ABCB1 gene encoding the membrane transporter P-glycoprotein, hypothesised to be under PKA modulation. The effects on the digestive gland are consistent with PROP blocking β-adrenoceptors. The observed increased cAMP levels in the mantle/gonad tissue support PROP blocking 5-HT1 receptors. Catalase and glutathione-S tranferase were differently affected by PROP in the two tissues. Mussel haemocyte lysosome membrane stability, a sensitive biomarker of animal health status, was concentration-dependently reduced following PROP exposure. Our observations provide evidence for PROP affecting cell signaling in M. galloprovincialis. Moreover, the chemical interacts with specific and evolutionally conserved biochemical pathways for which it was designed. The mode of action of PROP in mussels is related with its therapeutic properties in humans, based upon these conserved human targets. It also induced a stress response, and all these effects were displayed at the lowest concentrations tested
Fatigue in intensive care survivors one year after discharge
No full textBackground: Fatigue has not been investigated in long-term Intensive Care Unit (ICU) survivors. This study aimed to assess fatigue through a specific instrument, namely the Functional Assessment of Chronic Illness Therapy Fatigue (FACIT-F) scale, in ICU survivors one year after hospital discharge. A secondary aim was to compare the findings of FACIT-F with those of the Vitality domain (VT) of the 36-item Short-Form Health Survey (SF-36). Methods: This prospective cohort study was performed on 56 adult patients with a Length Of Stay (LOS) in ICU longer than 72 h. At one year after hospital discharge, FACIT-F and SF-36 questionnaires were administered to consenting patients by direct interview. FACIT-F was measured as raw (range 0-52), and FACIT-F-trans value (range 0-100). Past medical history, and demographic and clinical ICU-related variables were collected. Results: The patients' median age was 67.5, Simplified Acute Physiology Score II 31, and LOS in ICU 5 days. The median raw FACIT-F of the patients was 41, and Cronbach's α was 0.937. The correlation coefficient between FACIT-F-trans and VT of SF-36 was 0.660 (p < 0.001). Both FACIT-F and VT were related to dyspnoea scale (p = 0.01). A Bland-Altman plot of VT vs FACIT-F-trans showed a bias of -0.8 with 95 % limits of agreement from 35.7 to -34.1. The linear regression between differences and means was 0.639, suggesting a significant proportional bias. Conclusions: The 13-item FACIT-F questionnaire is valid to assess fatigue of long-term ICU survivors. VT of SF-36 relates to FACIT-F, but consists of only four items assessing two positive and two negative aspects. FACIT-F grasps the negative aspects of fatigue better than VT. Specific tools assess specific conditions better that general tools. Trial registration: ClinicalTrials.gov: NCT02684877
Validation of the cross-cultural adapted Italian version of the Oxford Elbow Score
No full textBackground: The Oxford Elbow Score (OES) is an English-language questionnaire specifically designed to evaluate surgical elbow outcomes. This scoring system has been translated into other languages. Given the lack of an Italian version of the OES, the present study was designed to establish, culturally adapt, and validate the Italian version.Methods: The OES questionnaire was culturally adapted to Italian patients in accordance with the literature guidelines with a pilot phase including seven patients with elbow problems and seven healthy subjects. The study includes 110 participants from three hospitals, who underwent elbow surgery for acute (70%) or chronic diseases. At least one month after elbow surgery, at the "index visit", the physician completed the Mayo Elbow Performance Index and patients completed the following questionnaires: the Italian OES, the shortened version of the Disability of Arm, Shoulder and Hand Questionnaire (QuickDASH) and the Short-Form 36 Health Survey. Internal consistency was evaluated using Cronbach's alpha. Reproducibility was assessed using the intraclass correlation coefficient in ten patients who completed the OES again two-three days after the index visit. Construct validity was assessed using Spearman correlation coefficients. Responsiveness was evaluated in 68 patients who answered the questionnaires four months after the index visit, using the Wilcoxon signed-rank test, the effect size and the standardized response mean calculation.Results: Cronbach's alpha was excellent: 0.86 (0.82-0.90) for OES pain, 0.92 (0.90-0.94) for OES function, and 0.90 (0.87-0.93) for OES social/psychological. The intraclass correlation coefficient was 0.94 (0.78-0.98) for OES pain, 0.91 (0.71-0.97) for OES function, 0.95 (0.83-0.98) for OES social-psychological and 0.93 (0.76-0.98) for OES total. The Spearman rho was >0.7 for OES pain and QuickDASH, for OES function and both QuickDASH and Mayo Elbow Performance Index, and for OES social-psychological and QuickDASH. Regarding responsiveness, the mean of the changes between the two visits ranged from 33.9 for OES pain, to 44 points for OES function and OES social/psychological. The effect size and the standardized response mean were >0.8 for all OES domains.Conclusion: This study demonstrates that the Italian version of the OES, translated in accordance with the international standardized guidelines, is reliable, valid, and responsive in patients who have undergoneelbow surgery
Bioaccumulation of algal toxins and changes in physiological parameters in Mediterranean mussels from the North Adriatic Sea (Italy)
No full textThe Northwestern Adriatic Sea is a commercially important area in aquaculture, accounting for about 90% of the Italian mussel production, and it was subjected to recurring cases of mussel farm closures due to toxic algae poisoning. A spatial and temporal survey of four sites along the North Adriatic Sea coasts of Emilia Romagna (Italy) was undertaken to study the possible impairments of physiological parameters in Mytilus galloprovincialis naturally exposed to algal toxins. The sites were selected as part of the monitoring network for the assessment of algal toxins bioaccumulation by the competent Authority. Samples positive to paralytic shellfish toxins and to lipophilic toxins were detected through the mouse bioassay. Lipophilic toxins were assessed by HPLC. Decreasing yessotoxins (YTX) levels were observed in mussels from June to December, while homo-YTX contents increased concomitantly. Lysosome membrane stability (LMS), glutathione S-transferase and catalase activities, and multixenobiotic resistance (MXR)-related gene expressions were assessed as parameters related to the mussel health status and widely utilized in environmental biomonitoring. Levels of cAMP were also measured, as possibly involved in the algal toxin mechanisms of action. Low LMS values were observed in hemocytes from mussels positive to the mouse bioassay. MXR-related gene expressions were greatly inhibited in mussels positive to the mouse bioassay. Clear correlations were established between increasing homo-YTX contents (and decreasing YTX) and increasing cAMP levels in the tissues. Similarly, significant correlations were established between the increase of homo-YTX and cAMP levels, and the expressions of three MXR-related genes at submaximal toxin concentrations. In conclusion, YTXs may affect mussel physiological parameters, including hemocyte functionality, gene expression and cell signaling
Differential sensitivity of mussel tissues to pharmaceutical exposures: Putative relationship with specific pathways of interaction
No full textPropranolol is a beta-adrenergic receptor-blocker widely used in cardiovascular diseases therapies, and detected in aquatic systems at concentrations up to 56 ng/L. Due to similarities between human and other vertebrate beta-adrenergic receptors, consequences of beta-blocker exposure in vertebrate wildlife, such as fish may be expected. Instead, little is known about the presence and function of these receptors in invertebrates, and possible effects of beta-blockers are then unpredictable. In a preliminary study [Fabbri et al. (2009) Comp. Biochem. Physiol 154A:S15] we showed that mussel exposure to 0.3 and 30 μg/L of (−)-propranolol caused a stress syndrome and alteration of cell signaling. Here we assessed whether propranolol in the chemical form and concentrations encountered in coastal environments induces detectable responses in mussels. Mussels (Mytilus galloprovinicialis) were exposed for 7 days to five concentrations of (±)-propranolol, namely 0.3, 3, 30, 300, 30,000 ng/L; the three lowest concentrations represented the environmental range. Different endpoints related to the beta-adrenergic pathway and to the stress response were evaluated in digestive gland and mantle, as the tissues showing the highest responsiveness in preliminary trials. Both cAMP levels and PKA activity were reduced in digestive gland, while increased in mantle. Similar expression patterns were observed for the MXR-related genes, a suite of transporters involved in xenobiotic metabolism. The opposite responses of the tissues may result from differently expressed receptor types, suggesting the occurrence of different interaction pathways. Significant effects were observed at concentrations as low as 0.3 ng/L, indicating that (±)-propranolol at environmental levels affects physiological pathways in mussels
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