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2018 Ocean Sciences Meeting, 11-16 February, in Portland, Oregon, Bottom trawling is a major driver of sedimentary dynamics in the deep sea, resuspending surface sediments and eroding the seafloor. Although the impacts of trawling on deep-sea sediment properties and the resulting impairment of the ecosystem functioning have been previously documented, its repercussions on the bioavailability of organic matter still need to be fully addressed. To provide insighits on this, biochemical composition of organic matter (proteins, lipids, carbohydrates, and phytopigments) along with sediment dry bulk density, grain size, and 210Pb concentrations were analyzed in triplicate sediment cores retrieved in trawled and untrawled sites from the Gulf of Castellammare, Sicily (Mediterranean Sea), during the EU Eurofleets-2 ISLAND (ExplorIng SiciLian CAnyoN Dynamics). The trawled site was severely eroded, as shown by the high dry bulk density and depleted excess 210Pb concentrations, whereas the excess 210Pb profile at the untrawled site revealed a 6 cm thick surface mixed layer derived from bioturbation overlaying softer sediments that had accumulated at an average rate of 0.15 cm yr-1. Overall, organic matter contents in the trawled site were 14-37% lower than those in the untrawled one. However, bioavailable organic matter (lipids, proteins, and phytopigments) concentrations in the uppermost layer were comparable in both trawled and untrawled sites, likely due to similar inputs of pelagic organic matter prior to the sampling period. Phytopigment concentrations decreased with depth along the cores at both sites, but at a ca. 20% higher rate in the trawled areas. This result suggests that persistent sediment resuspension and erosion due to trawling can modify food value of surficial sediments for the benthos more rapidly than biological consumption or sediment bioturbation. Then, we hypothesize that the biota in persistently trawled sediments may be more dependent upon the input from the overlaying water layers than that in untrawled sites

XXIII Congress of the Italian Association of Oceannography and Limnology, Functioning, alteration and restoration of aquatic ecosystems, 26-29 September 2017, Cagliari, Sardinia, Italy.-- XXIII Congresso della Associazione Italiana di Oceanologia e Limnologia - XXIII Congress of the Italian Association of Oceannography and Limnology, Funzionamento, alterazioni e recupero degli ecosistemi acquatici

This work deals with the effectiveness of dynamic analysis for a fixed landing gear, performed through a multi-body software by providing evidence of consistency between numerical simulation and experimental drop test results for the aircraft AP.68 TP-300. After the realization of Digital Mock-up of the main components of landing gear in a C.A.D. 3D, we have imported them in ADAMS environment and we have virtually mounted them to reproduce the real constraints. In ADAMS the model of the test article has been realized too. The fuselage of aircraft and constitutive parts of landing gear have been modeled all as rigid body. Only the leaf spring and tire have been simulated as flexible body. An ADAMS Tire Model has been used in the simulation and information about the ground has been added in a Road Data file. Simulations to reproduce experimental drop test, characterized by defined weights of falling mass and height, have been developed. The results show a good correlation between numerical simulation and experimental test, which provides preliminary evidence of future possible cost reduction through a potential virtual certification of the landing gear new design development. Future development of the present activity will probably be an application of methodology to other cases for a more extensive validation of its predictive power and development of virtual certification procedure.

The hemodynamic pattern of hypertrophied left ventricle in systemic hypertension was studied by M-mode echocardiography in 42 untreated hypertensive patients with left ventricular (LV) mass index greater than 2 standard deviations from the sex-specific mean of 114 normal subjects (normal values of our laboratory), and in 45 normotensive volunteers. Hypertensive patients showed cardiac dimensions, relative diastolic wall thickness, ratio of systolic pressure to end-systolic dimension, cardiac index and stroke index greater than normotensive control subjects (0.01 less than p less than 0.0001). Pressure/dimension ratio was correlated to relative wall thickness (p less than 0.005). End-systolic stress/volume ratio was normal as was systolic pressure to dimension ratio normalized for end-diastolic wall thickness. LV hypertrophy was concentric in 26% and eccentric in 74% of patients and suggested 2 different heart adaptations to overload: eccentric hypertrophy was associated with increased cardiac dimensions, high peak stress, normal systolic function and moderately increased LV contractility; concentric hypertrophy was associated with the highest blood pressure values, normal cardiac dimension, normal peak stress, normal systolic function and much increased LV contractility. Because stress/volume ratio and wall thickness-corrected systolic pressure/dimension ratio were normal in hypertensive patients, LV contractile capacity might be supported by the increase in myocardium available for contraction, rather than by increase in inotropic state.

Load changes were obtained in 7 females with untreated primary hypertension by means of controlled intravenous infusion of sodium nitroprusside (0.2mg/ml), in order to assess variations in the more usual indexes of left ventricular (LV) contractility to different loads and to verify that those indexes were independent of load. 2D-controlled M-mode echocardiograms were performed at baseline and when systolic blood pressure (SBP) had been reduced by 7, 16 and 23% for at least 5min. Heart rate did not change during the test; decrease in SBP was associated with either decreases in both end-systolic dimension (LVIDs) and end-systolic stress (ESS), or an increase in systolic function. SBP/LVIDs, SBP/end-systolic volume (ESV) and ESS/LVIDs ratios were examined and compared as indexes of contractile state. SBP/ESV and ESS/LVIDs ratios showed great variation at all stages as compared to baseline values, while the SBP/LVIDs ratio did not change. The percent variation between the baseline values and the last stage of the test was 51% for the ESS/LVIDs ratio, 37% for the SBP/ESV and 5% for the SBP/LVIDs ratio. Best-fitting regression showed that a linear relationship existed only between SBP and LVIDs. Echocardiographic two-dimensional (as ESS) or three-dimensional derivations (as ESV) should be carefully employed when the contractile state is studied, while the SBP/LVIDs ratio can be easily used as a baseline value, as it is insensitive to changes in load.

Forty-three subjects with uncomplicated primary hypertension and without echocardiographic left ventricular hypertrophy and 54 normotensive volunteers were studied by two-dimensional targeted M-mode echocardiography to evaluate systolic function and contractility before the development of compensatory hypertrophy. The ratio of peak systolic pressure to end-systolic dimension was used to assess left ventricular performance and was divided for either posterior wall thickness or cross-sectional area to generate hypertrophy-independent indices of inotropic state. Fractional shortening was normal in the hypertensive group, despite the increase in end-systolic stress. Systolic pressure/dimension ratio was higher in hypertensive subjects (p less than 0.001), as were hypertrophy-independent indices of inotropic state (p less than 0.005), which were inversely correlated to left ventricular mass (p less than 0.001). Values in 11 hypertensive subjects were above the upper confidence limit of the normal shortening/stress relation, which provides a load-independent measure of inotropic state. They showed high hypertrophy-independent indices of inotropic state (p less than 0.01), while the other hypertensive subjects did not. High fractional shortening, wall stress, and systolic pressure (p less than 0.01) were found in the subgroup with supernormal performance, while left ventricular mass was not different from that of other subgroups, depicting inadequate left ventricular hypertrophy. The duration of hypertension was the same in the subgroups. Supernormal inotropic state could be considered one form of primary adaptation to high wall stress that serves to maintain systolic ventricular performance.

Changes in hemodynamic variables regulating systolic function were assessed by M-mode echocardiography, under 2D control, in 11 patients with primary uncomplicated hypertension treated with nicardipine (60 mg/daily). At the end of treatment (8 weeks) blood pressure and end-systolic stress were greatly reduced (p less than 0.001), and systolic fractional shortening was increase (p less than 0.02). The percentage increase in fractional shortening was correlated with a decreased in end-systolic stress (r = 0.67). The index of left ventricular performance (systolic pressure/end-systolic dimension ratio) was reduced: no variation was found in the hypertrophy-independent index of the inotropic state (systolic pressure/end-systolic dimension ratio normalized for posterior wall thickness). No change in the inotropic state was caused by a negligible sympathetic reflex outflow: heart rate also remained unchanged. The only index of left ventricular hypertrophy which was slightly reduced after two months of treatment was left ventricular mass (p less than 0.001). In conclusion, the short-term treatment with nicardipine, in hypertensive patients, showed powerful effects in the improvement of systolic function; the possible regression of left ventricular hypertrophy must be confirmed in long-term therapy.

To assess left ventricular (LV) functional and structural changes associated with the reduction of blood pressure (BP) values during nicardipine administration (60 mg daily, for two months), 17 hypertensive patients were studied by M-mode echocardiography, according to a double-blind design (11 with nicardipine and six with placebo). Decrease in BP induced by nicardipine was associated with decrease in myocardial afterload (end-systolic stress) (P less than .002) and improvement of systolic function (fractional shortening) (P less than .02), without changes in inotropic state (assessed by systolic BP/end-systolic dimension/posterior wall thickness ratio). At the end of trial, a 5% reduction was found in LV mass (P less than .002), whereas relative wall thickness did not change. Diastolic phase (assessed by relaxation time index, and the slope of EF tract of the anterior mitral valve leaflet) was improved (.01 less than P less than .001). Patients with concentric and eccentric hypertrophy were separately considered. Relaxation time index and fractional shortening were significantly improved only in patients with concentric hypertrophy (P less than .01), whereas in the other ones the effect of treatment was variable. These differences were probably due to different effects on preload in the two LV hemodynamic patterns. Thus, nicardipine shows powerful effects on cardiac mechanics in systemic hypertension, but these effects are different according to LV anatomic pattern. Only in the presence of concentric hypertrophy is it possible to foresee the improvement of LV function; LV hypertrophy can be also reduced in concentric hypertrophy, but in the short term the reduction is too small to assume pathophysiologic significance.

Timing and rates of release of particulate organic matter (POM) beneath the Antarctic sea ice during the melting season are relatively unknown. To shed light on this topic, we investigated: i) quantity and biochemical composition of POM released below annual sea ice in Terra Nova Bay (TNB, Ross Sea, Antarctica) through sediment traps deployed at 10- and 30-m depth; ii) the abundance and taxonomic composition of phytoplankton; iii) the abundance and biochemical composition of two zooplankton species, namely the pteropods Clione limacina antarctica and Limacina helicina antarctica. Overall, our results show that in late spring-early summer in TNB the melting of annual sea ice determines a rapid release of particles into the underlying water column, and that those particles are transported downward at the rate of hours to days. POM fluxes were dominated by lipids, which probably resulted from zooplankton grazing activity on sea-ice algae and faecal pellets that were released into the water column. This, after the initial injection of particles, which were likely associated with sinking sympagic microalgal biomass derived from the sea ice melting, enhanced the nutritional value of POM. POM released beneath the sea ice, in turn, had a possible effect on the biochemical composition of the two pteropod species. Our results confirm that melting of sea ice in spring-summer each year in Antarctic coastal waters represents a fundamental step in the transfer of energy towards the higher trophic levels. Evidence of a decline in Antarctic sea ice over the last five years, plausibly as a consequence of global warming, underlines a conspicuous decline in habitat availability for sea-ice algae and, as a consequence, a drop in the availability of food for pteropods and the higher trophic levels of the coastal Antarctic Ocean.

L’attuale dibattito sul tema della Città Metropolitana in Italia, già vivo dagli anni sessanta in stretta relazione con i temi della città regione e della pianificazione regionale e in maniera istituzionale dagli anni novanta del XX secolo, trova un rinnovato interesse alla fine del 2013 quando si dibatte sull’opportunità di sopprimere l’istituto delle province e di riorganizzare la struttura amministrativa degli enti locali, ridefinendo compiti e responsabilità. Tutto ciò trova una sua codificazione circa un anno fa quando la L.n. 56/2014 converte il ddl Delrio dettando precise disposizioni legislative sulle città metropolitane, sulle province e sulle unioni e fusioni di comuni. Le conseguenze di tale legge sono state molto differenti secondo i contesti geografici e politici, in particolar modo in quelle regioni a statuto speciale che hanno potestà legislativa autonoma. La Sicilia, nello specifico, ha iniziato un iter di recepimento, e trasformazione in legge propria, dei contenuti della legge suddetta, senza peraltro a oggi essere arrivati a una definizione precisa e compiendo passi avanti e passi indietro, e talvolta anche laterali, quasi a volere compiere un percorso circolare per tornare al punto di partenza. Il contributo vuole offrire un quadro attuale dei processi che sono seguiti a tali disposizioni legislative, prendendo come caso studio la città di Palermo.

La particolare fragilità degli ecosistemi fluviali rispetto ai radicali processi di antropizzazione che hanno investito la Campania già a partire dalla metà del secolo scorso, rappresenta uno dei principali interessi di studio per i geografi che si occupano di rischio ambientale, pianificazione e paesaggio. Il contributo prende in esame i territori del fiume Sarno e del Volturno per individuare, anche attraverso la chiave di lettura del paesaggio, strategie di riqualificazione ambientale, pianificazione e contrasto del rischio e sviluppo sostenibile.

“Immagini di territori metropolitani” rappresenta una raccolta che anticipa una riflessione più organica e interpretativa sulle 14 Città metropolitane italiane. Palermo è una di queste e il testo mette in evidenza l'intero e complesso processo che ha portato all'attuale asseto amministrativo del territorio metropolitano.

Nell’Europa contemporanea si registra un’ampia varietà di comunità culturali. Alcune di queste comunità possono, naturalmente, essere costruite su valori e modi di vita che sono così antisociali da renderli immeritevoli di supporto e tolleranza, ma – in ogni caso e come dato di fatto – la società contemporanea è divisa in un arcipelago frammentato di differenti minoranze e gruppi plurali. Riteniamo questi gruppi come socialmente costruiti – cioè come fenomeni sociali dinamici i cui confini si spostano nel tempo, e la cui rilevanza nella vita dei membri e in quella di coloro che non ne fanno parte varia nel tempo e nello spazio: questa visione è emersa all'interno del dibattito sui nuovi movimenti sociali, evidenziando il ruolo degli aspetti sociali e culturali nei cambiamenti collettivi (Melucci, 1989; Giddens, 1991). Con riferimento alla loro dimensione spaziale, questi gruppi possono essere comunità emarginate o segregate e, in alcuni casi, appaiono come “gated communities”. Confini materiali e immateriali creano la divisione spaziale, sociale e culturale tra i gruppi. Allo stesso tempo, i confini sono alla base della divisione tra sfera pubblica e privata che è anche una separazione tra spazi pubblici e privati. Tra la sfera pubblica e quella privata esiste (potenzialmente) una zona di “soglia” delle reti sociali e delle azioni comunitarie. Nuove forme di costruzione di “spazi comuni” (materiali e immateriali) aumentano nelle frange più marginali della città come pratiche innovative del vivere e lavorare insieme. Con questo contributo intendiamo esplorare la questione delle aree “soglia” nella sua doppia interpretazione: 1. come luoghi fisici, dove gruppi marginali o esclusi sono costretti a sperimentare azioni collettive per ottenere migliori condizioni di vita (urbane); 2. come metafora di un infra-spazio tra sfera pubblica e privata, che è anche precondizione per l'esistenza dello spazio pubblico della democrazia. In tale approccio, la sostanziale precondizione per qualsiasi forma di democrazia è l'esistenza di spazi politici come l’idea di Arendt di un "infra-spazio" tra pari che discutono e agiscono liberamente. Così, lo spazio pubblico della democrazia coincide con lo spazio politico della libertà. Dove lo spazio tangibile dell'Agorà e quello metaforico della democrazia non esistono, non c’è spazio politico (Arendt, 1958). In termini di pianificazione non esiste uno spazio (in termini anche di efficacia) per i processi di pianificazione partecipativa. Al fine di illustrare le nostre considerazioni su questo tema, useremo alcuni concetti sviluppati da Hannah Arendt (1958), applicandoli al discorso politico nella pianificazione di processi partecipativi. Questo ci porta a considerare e soppesare alcune ambiguità e retoriche che compongono il concetto di pratiche partecipative inclusive, e di individuare alcune precondizioni inevitabili al fine di costruire efficienti processi di pianificazione partecipativa, considerando che l'interesse pubblico e la costruzione del consenso ricevono bassa priorità politica. There is, in contemporary Europe, a wide variety of cultural communities. Some of these cultural communities may, of course, be built around values and ways of life, which are so anti-social as to make them unworthy of toleration or support, but – in any case and as a matter of fact – contemporary society is divided into a fragmented and diversified archipelago of minority and plural groups. We view these groups as socially constructed – i.e. as dynamic social phenomena whose boundaries shift over time, and whose salience in the lives of members and non-members varies over time and place: this view emerged within the debate on new social movements, highlighting the role of social and cultural elements in social changes (Melucci, 1989; Giddens, 1991). In reference to their spatial dimension, these groups can be marginalised or segregated communities, and in some cases they appear as ‘gated’ communities. Material and immaterial boundaries create the spatial, social and cultural division between groups. At the same time, boundaries are at the base of the division between private and public spheres that is also between public and private spaces. Between the private and the public sphere, a ‘threshold’ area of social networks’ and community actions does (potentially) exist. New forms of construction of (material and immaterial) ‘common spaces’ rise in the most marginal fringes of the city, as innovative practices of ‘work and live’ together. In this paper we would like to explore the issue of the ‘threshold areas’ in its double interpretation: 1. as physical places where marginal or excluded groups are forced to experiment collective actions in order to gain better (urban) life conditions; 2. as metaphor of an infra-space between private and public sphere, which is also as a pre-condition for the existence of the public space of democracy. In this approach, the substantial precondition for any form of democracy is the existence of political spaces such as the Arendt’s idea of a discursive and acting “infra-space” among equal individuals freely debating. Thus, the public space of democracy coincides with the political space of freedom. Where the tangible space of the agora and the metaphorical space of democracy do not exist, there is no political space (Arendt, 1958). In planning terms, there is no space (that is also efficacy) for participative planning processes. In order to illustrate our considerations on this issue, we will use some concepts as developed by Hannah Arendt (1958), applying them to the political discourse in planning participatory processes. This leads us to consider and weigh up some of the rhetoric and ambiguities making up the concept of inclusionary participative practices, as well as individuating some unavoidable preconditions in order to build up efficient participative planning processes, whereas public interest and consensus building receive low policy priority.

Il contributo riporta il lavoro di ricerca svolto nei centri storici di Caserta al fine di rilevare la percezione dei luoghi e la potenziale riqualificazione economica e sociale.

A partire dalle formulazioni della Convenzione Europea sul Paesaggio, se ne discute lo stato di avanzamento in termini di pratiche reali e le difficoltà di applicazione in relazione alla crescente complessità delle procedure e del quadro degli attori coinvolti.