Energetic model of tumor growth

A macroscopic model of the tumor Gompertzian growth is proposed. This approach is based on the energetic balance among the different cell activities, described by methods of statistical mechanics and related to the growth inhibitor factors. The model is successfully applied to the multicellular tumor spheroid data.Comment: 5 pages, 2 figures, contribution to "Complexity, Metastability and Nonextensivity", Erice, July 200

A new perspective on the irregular satellites of Saturn - II Dynamical and physical origin

The origin of the irregular satellites of the giant planets has been long debated since their discovery. Their dynamical features argue against an in-situ formation suggesting they are captured bodies, yet there is no global consensus on the physical process at the basis of their capture. In this paper we explore the collisional capture scenario, where the actual satellites originated from impacts occurred within Saturn's influence sphere. By modeling the inverse capture problem, we estimated the families of orbits of the possible parent bodies and the specific impulse needed for their capture. The orbits of these putative parent bodies are compared to those of the minor bodies of the outer Solar System to outline their possible region of formation. Finally, we tested the collisional capture hypothesis on Phoebe by taking advantage of the data supplied by Cassini on its major crater, Jason. Our results presented a realistic range of solutions matching the observational and dynamical data.Comment: 26 Pages, 21 Figure

Hybrid neutron stars within the Nambu-Jona-Lasinio model and confinement

Recently, it has been shown that the standard Nambu-Jona-Lasinio (NJL) model is not able to reproduce the correct QCD behavior of the gap equation at large density, and therefore a different cutoff procedure at large momenta has ben proposed. We found that, even with this density dependent cutoff procedure, the pure quark phase in neutron stars (NS) interiors is unstable, and we argue that this could be related to the lack of confinement in the original NJL model.Comment: 2 pages, 1 figure, to be published in the proceedings of the conference EXOCT07, Catania, 11-15 June, 200

Wind Energy: UK Experiences and Offshore Operational Challenges

This paper presents a discussion of the development of wind energy generation in the United Kingdom and the challenges faced by the wind industry including reliability, performance and condition monitoring, particularly in the offshore environment. The worldwide installed capacity of offshore wind has now risen to over 7 GW, with an ever increasing deployment rate of new assets. About 90% of the global currently installed capacity is in Northern Europe, with the United Kingdom having the world's largest share at 4 GW. Capacity factor data from UK offshore wind farms is presented, providing an insight into the current performance of large Round 2 offshore wind farms compared to the earlier Round 1 farms and to onshore farms. The data reveal that the United Kingdom's Round 2 offshore farms are achieving an average monthly capacity factor of 38.3% with a peak value of 75.8%. The older Round 1 farms have a lower average capacity factor of 33.6% while large onshore farms with capacities above 100 MW have achieved 25.6%. Offshore wind turbine performance has improved over time, and the industry is applying the learning from early experiences to achieve better performances at the more recently installed farms. Despite these improvements in turbine availability, the cost of energy from wind, particularly offshore, remains too high for it to be a commercially viable form of generation without subsidies. Reducing the cost of energy from wind to economically sustainable levels is the most important challenge facing the industry today. Operation and maintenance costs constitute up to 30 % of the total cost of energy from wind in large farms. The industry must overcome the challenges associated with improving component reliability and the development and adoption by operators of appropriate condition monitoring systems and maintenance strategies, in order to reduce costs to sustainable levels. Research and development work carried out with these goals in mind is also reviewed in the paper

Arbitrato Internazionale e Ordine Pubblico Internazionale. Origine, Problematica e Teoria Conflittualistica

The principle of the autonomy of the contract will in the choice of procedure law is an axiom in international trade disputes. Nevertheless, in several legal systems there are restrictions to this principle residing in the public policy. It is possible to identify the principles of public policy such as those that inspire a particular jurisdiction and are an echo of the fundamentals values of a society. The concept responds to a general idea of the supremacy of society over individuals. Public policy is a mechanism by which the State represses special agreements that may pose a threat to its essential interests and political relations. The methodology used is documentary. .      El principio de la autonomia de la voluntad privada en el ámbito contractual para efectos del derecho procesal aplicable es un axioma en las relaciones de comercio transnacionales. No obstante, en diversos sistemas jurídicos pueden encontrarse límites a este principio que residen en las normas de orden público. Es posible individuar los principios de orden público como aquellos que inspiran un determinado ordenamiento juridco y que reflejan los valores esenciales de una sociedad. El concepto responde a una idea general de supremacía de la sociedad sobre el individuo. En realidad, representa un mecanismo mediante el cual el Estado reprime las estipulaciones privadas que pueden constituir una amenaza para los intereses esenciales y para las relaciones políticas. La metodologia usada es de naturaleza documental.Il principio dell’autonomia della volontà delle parti in materia contrattuale, nella scelta del diritto che regolerà il procedimento in caso di controversia, è un assioma dei legami commerciali transfrontalieri. Ciononostante, nei diversi sistemi giuridici possono trovarsi dei limiti a tale principio che risiedono nelle norme di ordine pubblico. E’ possibile individuare i principi di ordine pubblico come quelli che ispirano un determinato ordinamento giuridico e che sono il riflesso dei valori essenziali di una società. Il concetto risponde ad un’idea generale di supremazia della società sull’individuo. In realtà è un meccanismo mediante il quale lo Stato reprime le convenzioni particolari che possono costituire una minaccia per i propri interessi essenziali e per le relazioni politiche. La metodologia usata è di natura documentale

Arbitrato internazionale e ordine pubblico internazionale: Norme Imperative e A-nazionalità

It is conceptually impossible speak of international public policy by adding the “French” adjective or “Portuguese”, because in this case, is no longer international public policy but it is public policy of the State of the adjective. The state judge exercises control from the perspective of the principles that govern its own internal order and, therefore, has no competence in the broad sense of the term, to provide for the implementation of the international public policy.Es imposible hablar conceptualmente de orden público internacional agregándole un gentilicio como francés o portugués, porque deja de ser internacional para convertirse en orden público del Estado del gentilicio. El juez estatal ejerce un control desde la perspectiva de los principios que gobiernan su propio orden público interno, por consiguiente, no tiene competencia, en el sentido amplio de la palabra, ni atribución para disponer de la aplicación del orden público internacional.È concettualmente impossibile quindi parlare di ordine pubblico internazionale aggiungendo l›aggettivo “francese” o “portoghese”, perché in tal caso, non è più ordine pubblico internazionale ma è ordine pubblico dello Stato dell›aggettivo. Il giudice statale esercita un controllo dalla prospettiva dei principi che governano il proprio ordine interno e, pertanto, non ha competenza, nel senso ampio del termine, per disporre l›applicazione dell›ordine pubblico internazionale