350 research outputs found
Il sistema portuale siculo-maltese per lo sviluppo del trasporto merci e della logistica nel contesto euromediterraneo
La politica dell’Unione Europea pone grande importanza ad uno sviluppo del trasporto efficiente e
sostenibile, da attuarsi attraverso il rafforzamento dei traffici intermodali e la liberalizzazione dei porti
con tariffe competitive nei servizi di movimentazione container. Il Mediterraneo, in particolare, ha visto
una notevole espansione di tale tipologia di traffico, dovuta a una rinnovata centralitĂ per il trasferimento
del fulcro dell’economia mondiale verso l’Estremo Oriente. La programmazione europea al 2020 ha,
inoltre, ridefinito il Corridoio I delle reti TEN-T, estendendo l’asse da Helsinki a Malta, includendo la
Sicilia. In una situazione globale di questo genere i porti di queste aree potrebbero acquisire una
condizione di vantaggio competitivo.
Questo lavoro analizza la situazione attuale e le potenzialitĂ del sistema portuale siculo-maltese, tema
d’interesse per la valutazione di politiche d’intervento infrastrutturale e organizzativo. Il presente articolo,
dopo aver analizzato l’andamento dei traffici, la dotazione di infrastrutturale e il ruolo che tali porti
ricoprono nel Mediterraneo, si sofferma sulle politiche europee e nazionali rilevanti per questi scali. In
tale scenario emerge una traiettoria di sviluppo necessaria ma anche rischiosa, che deve considerare
attentamente i costi-opportunitĂ nella realizzazione di grandi opere di ammodernamento e di
collegamento. L’obiettivo del rilancio del sistema portuale siculo-maltese è possibile perché vi sono i
presupposti non solo geografici ma anche commerciali. E’ però necessario investire sulle
infrastrutture per rendere funzionale la circolazione delle merci all’interno di tale sistema logistico
integrato. In assenza di tali interventi si rischia di non cogliere possibili opportunitĂ ma, addirittura, di
scomparire come porti container. Il lavoro si conclude formulando alcune proposte di policy per evitare
tale rischio e prospettando un percorso di sviluppo basato su nuove, e possibili, sinergie
Dexamethasone in glioblastoma multiforme therapy : mechanisms and controversies
Glioblastoma multiforme (GBM) is the most common and malignant of the glial tumors. The world-wide estimates of new cases and deaths annually are remarkable, making GBM a crucial public health issue. Despite the combination of radical surgery, radio and chemotherapy prognosis is extremely poor (median survival is approximately 1 year). Thus, current therapeutic interventions are highly unsatisfactory. For many years, GBM-induced brain oedema and inflammation have been widely treated with dexamethasone (DEX), a synthetic glucocorticoid (GC). A number of studies have reported that DEX also inhibits GBM cell proliferation and migration. Nevertheless, recent controversial results provided by different laboratories have challenged the widely accepted dogma concerning DEX therapy for GBM. Here, we have reviewed the main clinical features and genetic and epigenetic abnormalities underlying GBM. Finally, we analyzed current notions and concerns related to DEX effects on cerebral oedema, cancer cell proliferation and migration and clinical outcome.peer-reviewe
A dynamic assessment of instrument interaction and timing alternatives in the EU low-carbon policy mix design
The European Union low-carbon strategy includes a range of complementary policies. Potential interactions between instruments and different timing of their implementation can influence the cost and likelihood of achieving the targets. We test the interactions between the three main pillars of the European Union strategy through a dynamic Computable General Equilibrium model (GDynEP) with a time horizon of 2050. Main results are: i) going for the unilateral European Union carbon mitigation target without any complementary technological policy will produce large economic losses; ii) by investing in clean energy technologies (energy efficiency and renewable energy) with a carbon tax revenue recycling mechanism, these losses will decrease substantially; iii) when complementary clean energy technology policies are implemented, the optimal timing of binding targets changes; iv) the higher the public support to clean energy technologies, the larger the economic gains in early adoption of challenging abatement targets. © 2018 Elsevier LtdWe acknowledge financial support received by the EU D.G. Research (research project “CECILIA2050 — Choosing efficient combinations of policy instruments for low-carbon development and innovation to achieve Europ
A neural network based technique for short-term forecasting of anomalous load periods
The paper illustrates a part of the research activity conducted by authors in the field of electric Short Term Load Forecasting (STLF) based on Artificial Neural Network (ANN) architectures. Previous experiences with basic ANN architectures have shown that, even though these architectures provide results comparable with those obtained by human operators for most normal days, they evidence some accuracy deficiencies when applied to ''anomalous'' load conditions occurring during holidays and long weekends. For these periods a specific procedure based upon a combined (unsupervised/supervised) approach has been proposed. The unsupervised stage provides a preventive classification of the historical load data by means of a Kohonen's Self Organizing Map (SOM) The supervised stage, performing the proper forecasting activity, is obtained by using a multi-layer perceptron with a backpropagation learning algorithm similar to the ones above mentioned. The unconventional use of information deriving from the classification stage permits the proposed procedure to obtain a relevant enhancement of the forecast accuracy for anomalous load situations
Overexpression of Large-Conductance Calcium-Activated Potassium Channels in Human Glioblastoma Stem-Like Cells and Their Role in Cell Migration
Glioblastomas (GBMs) are brain tumors characterized by diffuse invasion of cancer cells into the healthy brain parenchyma, and establishment of secondary foci. GBM cells abundantly express large-conductance, calcium-activated potassium (BK) channels that are thought to promote cell invasion. Recent evidence suggests that the GBM high invasive potential mainly originates from a pool of stem-like cells, but the expression and function of BK channels in this cell subpopulation have not been studied. We investigated the expression of BK channels in GBM stem-like cells using electrophysiological and immunochemical techniques, and assessed their involvement in the migratory process of this important cell subpopulation. In U87-MG cells, BK channel expression and function were markedly upregulated by growth conditions that enriched the culture in GBM stem-like cells (U87-NS). Cytofluorimetric analysis further confirmed the appearance of a cell subpopulation that co-expressed high levels of BK channels and CD133, as well as other stem cell markers. A similar association was also found in cells derived from freshly resected GBM biopsies. Finally, transwell migration tests showed that U87-NS cells migration was much more sensitive to BK channel block than U87-MG cells. Our data show that BK channels are highly expressed in GBM stem-like cells, and participate to their high migratory activity. This article is protected by copyright. All rights reserved
The role of ion channels in the hypoxia-induced aggressiveness of glioblastoma
The malignancy of glioblastoma multiform (GBM), the most common and aggressive form of human brain tumors, strongly correlates with the presence of hypoxic areas, but the mechanisms controlling the hypoxia-induced aggressiveness are still unclear. GBM cells express a number of ion channels whose activity supports cell volume changes and increases in the cytosolic Ca2+ concentration, ultimately leading to cell proliferation, migration or death. In several cell types it has previously been shown that low oxygen levels regulate the expression and activity of these channels, and more recent data indicate that this also occurs in GBM cells. Based on these findings, it may be hypothesized that the modulation of ion channel activity or expression by the hypoxic environment may participate in the acquisition of the aggressive phenotype observed in GBM cells residing in a hypoxic environment. If this hypothesis will be confirmed, the use of available ion channels modulators may be considered for implementing novel therapeutic strategies against these tumors.peer-reviewe
Reconciling the discrepancies on the involvement of large-conductance Ca2+-activated K channels in glioblastoma cell migration
Glioblastoma (GBM) is the most common and aggressive primary brain tumor, and is notable for spreading so effectively through the brain parenchyma to make complete surgical resection virtually impossible, and prospect of life dismal. Several ion channels have been involved in GBM migration and invasion, due to their critical role in supporting volume changes and Ca2+ influx occuring during the process. The large-conductance, Ca2+-activated K (BK) channels, markedly overexpressed in biopsies of patients with GBMs and in GBM cell lines, have attracted much interest and have been suggested to play a central role in cell migration and invasion as candidate channels for providing the ion efflux and consequent water extrusion that allow cell shrinkage during migration. Available experimental data on the role of BK channel in migration and invasion are not consistent though. While BK channels block typically resulted in inhibition of cell migration or in no effect, their activation would either enhance or inhibit the process. This short review reexamines the relevant available data on the topic, and presents a unifying paradigm capable of reconciling present discrepancies. According to this paradigm, BK channels would not contribute to migration under conditions where the [Ca2+]i is too low for their activation. They will instead positively contribute to migration for intermediate [Ca2+]i, insufficient as such to activate BK channels, but capable of predisposing them to cyclic activation following oscillatory [Ca2+]i increases. Finally, steadily active BK channels because of prolonged high [Ca2+]i would inhibit migration as their steady activity would be unsuitable to match the cyclic cell volume changes needed for proper cell migration.peer-reviewe
A Risk-Based Methodology and Tool Combining Threat Analysis and Power System Security Assessment
A thorough investigation of power system security requires the analysis of the vulnerabilities to natural and man-related threats which potentially trigger multiple contingencies. In particular, extreme weather events are becoming more and more frequent due to climate changes and often cause large load disruptions on the system, thus the support for security enhancement gets tricky. Exploiting data coming from forecasting systems in a security assessment environment can help assess the risk of operating power systems subject to the disturbances provoked by the weather event itself. In this context, the paper proposes a security assessment methodology, based on an updated definition of risk suitable for power system risk evaluations. Big data analytics can be useful to get an accurate model for weather-related threats. The relevant software (SW) platform integrates the security assessment methodology with prediction systems which provide short term forecasts of the threats affecting the system. The application results on a real wet snow threat scenario in the Italian High Voltage grid demonstrate the effectiveness of the proposed approach with respect to conventional security approaches, by complementing the conventional "N - 1" security criterion and exploiting big data to link the security assessment phase to the analysis of incumbent threat
Comparing the Cana Brava and Niquelândia complexes: large mafic-ultramafic intrusions in the lower crust and contamination processes
Mafic-ultramafic complexes offer a unique opportunity to study how intrusions of mantlederived melts growth into the deep crust and interact with the country rocks. The Cana Brava and Niquelândia complexes are two mafic-ultramafic bodies which outcrop within the Brasilia Belt (Goias, central Brazil) and that intruded the metavolcanicmetasedimentary sequences of Palmeiropolis and Indaianopolis during a Neoproterozoic continental rifting. The two complexes are parts, together with the Barro Alto complex, of a ~350 km NNE-trend belt of layered bodies which were exhumed during the Gondwana formation. New field, geochemical and isotopic data give new constraints on the model of growth of these complexes and the interactions between parent melts and the lower crust. Field evidences suggest that the complexes grow via multiple-melt intrusions under hyper- to subsolidus shear conditions. During the complex growth, the upper metavolcanic-metasedimentary sequence was delaminated and xenoliths were incorporated and deformed within the crystal mush. The increase of the 87Sr/86Sr(790) along the complex stratigraphy, coupled with a decrease of the εNd(790), provides evidences of strong crustal contamination by the embedded xenoliths. The enrichment in most incompatible elements (e.g. K, Ba and LREE) and hydrous phases (biotite and amphibole) in rocks containing more xenoliths supports also the crustal contamination. The almost linear trend of isotopic contamination suggests that this process involved all the magma colum, similarly to AFC. However, the increase abundance of incompatible elements and H2O contents toward xenoliths-rich bands provide for a local effect of contamination
Effects of Diets Enriched in Linseed and Fish Oil on the Expression Pattern of Toll-Like Receptors 4 and Proinflammatory Cytokines on Gonadal Axis and Reproductive Organs in Rabbit Buck
Infections of the genital tract can perturb the fertility in humans and animals. Pathogen recognition and activation of innate immunity onset through the pattern recognition receptor activation, such as Toll-like receptor 4 (TLR4), leading to the production of proinflammatory cytokines and mediators. TLR4 is expressed both on leukocytes and nonimmune cells. Rabbit TLR4 shows great similarity to its human counterpart. Moreover, the TLR4 signalling pathway could be modulated by long-chain polyunsaturated fatty acids (LC-PUFA). The objectives of this study were (i) to determine the expression levels of TLR4 and proinflammatory cytokines in the reproductive hypothalamic-gonadal axis of the male rabbit and (ii) to evaluate if the n-3 PUFA-enriched diets can modify their expression levels in the tissues and LC-PUFA profiles in seminal plasma. Fifteen rabbit bucks (n=5/experimental group) were fed with different diets: Commercial standard (group C), rich in extruded linseed (10%, group L), and in fish oil (3%, group FO) for 110 days. TLR4, TNF-, and IL-1β mRNA were ubiquitously expressed throughout the hypothalamic-gonadal axis. However, TLR4 mRNA expression was lower in the hypothalamus than the epididymis (P<0.01), seminal vesicles (P<0.01), and pituitary gland (P<0.05). Dietary enrichment in PUFA did not modify the gene expression profile nor the histological characteristics of the tissues. Conversely in seminal plasma, rabbits fed with L and FO had lower n-6 (P<0.05), LC-PUFA n-6 (P<0.05), and n-6/n-3 ratio (P<0.05) but higher n-3 (P<0.001) and LC-PUFA n-3 (P<0.01) compared to the control group. Our study builds a map of the gene expression of TRL4 and proinflammatory cytokines in the reproductive hypothalamic-gonadal axis of the male rabbit, fundamental step for understanding the immune defence mechanisms. Diets enriched in LC-PUFA did not affect basal gene expression but modulated sperm fatty acid composition. Finally, rabbit may be an excellent animal model to study the relationship between inflammation and infertility, and the nutritional modulation of immune functions
- …