1435 research outputs found
Sort by
Indagine conoscitiva sulla numerosità degli allevamenti cunicoli nella provincia di pisa e sulle loro problematiche sanitarie
No full textRIASSUNTO L’allevamento del coniglio rappresenta un settore importante della zootecnia italiana, con una produzione di circa 100.000.000 di capi/anno distribuiti in circa 8.000 aziende, alle quali si aggiungono i piccoli allevamenti rurali che rappresentano una parte non marginale di tale settore. In questo studio ci siamo prefissi di valutare, mediante l’uso di un questionario, la numerosità degli allevamenti cunicoli rurali presenti nella provincia di Pisa e di mettere in evidenza quali siano le patologie più significative presenti in tale tipo di allevamento. Dall’indagine è emerso che le problematiche sanitarie risultano sia correlate a carenze igienico-sanitarie (degli ambienti, delle strutture e delle attrezzature) che alla non sistematica applicazione delle misure di profilassi vaccinale. La Malattia Emorragica Virale (MEV), infatti, comparsa a metà degli anni ‘80 è divenuta endemica e la Mixomatosi non ha più un andamento stagionale ma è presente tutto l’anno. SUMMARY The rabbit-farming is an important area of Italian zootechnics. There are about 8,000 farms, producing 100,000,000 head/year, and a lot of rural rabbit-farms. The aim of this study has been to value the number of rural rabbit-farm and to point out the most important diseases. This study has pointed out that the health issues are correlated to sanitary precautions deficiency (breeding environment, structure and equipment) and irregular application of vaccine prophylaxis. Rabbit Hemorrhagic Disease (RHD), in fact, appeared in the middle of year ’80, becoming an endemic disease, and Myxomatosis hasn’t got a seasonal trend any more, but it is present all year round
Teorie architettoniche nella Vienna fin-de-siècle: gli scritti di Camillo Sitte e di Otto Wagner
Get PDFL'articolo analizza gli scritti principali di Camillo Sitte ed Otto Wagner, nel clima culturale della Vienna fin-de-siècle, evidenziando l’importanza del loro contributo teorico alla definizione dell’urbanistica come arte e all’interpretazione del ruolo dell’architetto nella società moderna
Poesie per un "liberato mondo" : antologia
No full textRIASSUNTO E' presentata una antologia delle poesie di Antonio Gamberi, poeta-minatore, socialista e antifascista, vissuto a cavallo tra ’800 e ’900. Gamberi, autodidatta, insegna a leggere e scrivere ai suoi compagni, perché quella di saper leggere e scrivere era, sul finire dell’Ottocento, una condizione indispensabile per poter votare, ma trova nello studio e nella cultura molto di più di uno strumento politico, vi trova il riscatto dall’ignoranza, il riscatto dalla sudditanza alle classi dirigenti colte e ricche. Solo quel riscatto, a suo modo di vedere, avrebbe permesso a lui e ai suoi compagni minatori di dar vita ad una società come egli spesso diceva “di giusti e di eguali”. Le sue poesie sono dunque partecipi di un periodo storico e sociale segnato da lotte contadine ed operaie per la libertà e per un mondo più giusto; Gamberi, minatore a Ribolla, partito da Roccatederighi per approdare in Spagna, in Belgio e in Francia, dove morì, rappresenta uno degli esempi più fulgidi di quei poeti militanti, cantori della tradizione risorgimentale, laica, anticlericale, libertaria e socialista, diffusa in Toscana e in Maremma in particolare. SUMMARY Poetry anthology of Antonio Gamberi, poet-miner, Socialist and antifascist, lived between ' 800 and ' 900, continuer of one lay tradition, anticlerical and socialist, diffused in Tuscany and Maremma in particular
ASSIST as a Research Framework for High-performance Grid Programming Environments
No full textASSIST (A Software development System based upon Integrated Skeleton Technology) is a programming environment oriented to the development of parallel and distributed high-performance applications according to a unified approach. The language and implementation features of ASSIST are a result of our long-term research in parallel programming models and tools. ASSIST is evolving towards programming environments for high-performance complex enabling platforms, especially Grids. In this paper, we show how ASSIST can act as a valid research vehicle to study, experiment and realize Grid-aware programming environments for high-performance applications. Special emphasis is put on the innovative methodologies, strategies and tools for dynamically adaptive applications, that represent the necessary step for the success of Grid platforms.
First we discuss the conceptual framework for Grid-aware programming environments, based upon structured parallel programming and components technology, anticipating how ASSIST possesses the essential features required by such framework. Then we summarize the ASSIST programming model, showing its evolution, along the line of structured parallel programming, to solve critical problems of expressive power, flexibility, interoperability and efficiency; some examples, both of kernels and of complex applications, are used to point out the ASSIST features. The modular compiler model and the current implementation for heterogeneous platforms and Globus-based Grids are illustrated. We show the features that allow ASSIST programs to be used in CORBA infrastructures, that represents our basic starting point towards interoperability in Grid applications. Finally, the presentation of all the previous issues is used to derive an ASSIST-based model for supporting dynamically adaptive applications
Topological susceptibility of SU(N) gauge theories at finite temperature
No full textWe investigate the large-N behavior of the topological susceptibility in
four-dimensional SU(N) gauge theories at finite temperature, and in particular
across the finite-temperature transition at Tc. For this purpose, we consider
the lattice formulation of the SU(N) gauge theories and perform Monte Carlo
simulations for N=4,6. The results indicate that the topological susceptibility
has a nonvanishing large-N limit for T<Tc, as at T=0, and that the topological
properties remain substantially unchanged in the low-temperature phase. On the
other hand, above the deconfinement phase transition, the topological
susceptibility shows a large suppression. The comparison between the data for
N=4 and N=6 hints at a vanishing large-N limit for T>Tc
PB_Cube: a join algorithm on Hypercube Systems
No full textThis paper presents and analyzes a join algorithm for cube-connected
multiprocessors. The algorithm, called PB_Cube, was developed to
exploit as much as possible the hypercube structural characteristics,
enabling us to achieve synchronization between processors, maximum
parallelism and a reduction of the traffic on the network. Moreover,
it doesn't present any bucket overflow and buffer overflow
problems. Experimental results indicate the algorithm has linear
speedup and scale-up in a significant range. Furthermore its performance
is comparable with that of Hybrid Hash [9] join and better than that
of Parallel Distributive algorithm [4]. Our algorithm has the
advantage of being able to handle non-equijoin. These results become
even more interesting when we consider that the costs for Hybrid Hash
and Parallel Distributive algorithms are given under hypothesis
stronger than ours
General Restricted Rotation Distance
No full textThe restricted rotation distance d_{R}(S,T) between two trees S, T of n vertices is the minimum number of rotations by which S can be transformed into T, where rotations can only take place at the root of the tree, or at the right child of the root. A sharp upper bound d_{R}(S,T)\leq 4n-8 is known, based on the word metric of Thompson's group.
We refine this bound to d_{R}(S,T)\leq 4n-8-\rho_{S} \rho_{T}, where \rho_{S} and \rho_{T} are the numbers of vertices in the rightmost vertex chains of the two trees, providing a very simple transformation algorithm based on elementary
properties of trees. We also generalize the concept of restricted rotation by allowing
rotations at the highest k levels of the tree, and study the new distance for k=2,3
Experiments with "extended crossover" approaches for network flow problems
No full textInterior Point algorithms for Min-Cost Flow problems have been shown to be competitive with more established "combinatorial" approaches, at least on some problem classes and for very large instances. A fundamental contribution to the efficiency of these approaches is provided by the specialized crossover routines that can be implemented for this problem; they allow early termination of the IP approach, sparing it with the "nasty" iterations where the core linear systems become very difficult to solve by iterative algorithms. Because crossover procedures are nothing but one step of a combinatorial approach to MCF, we propose to extend this concept to that of extended crossover: use the initial part of an Interior Point algorithm to MCF to warm-start a "combinatorial" algorithm. We report our experiments along this line using, as "combinatorial companion" , a primal-dual algorithm for MCF that has a natural way for exploiting the information provided by the IP approach. Our results show that the efficiency of the combined approach critically depends on the accurate selection of a set of parameters among very many possible ones, for which designing accurate guidelines appears not to be an easy task; however, they also show that the combined approach can be competitive with the two original approaches in isolation, at least on some "difficult" instances
Optimal Mobile Agent Protocols for Searching a Black Hole in Arbitrary Networks
No full textConsider a networked environment, supporting mobile agents, where
there is a black hole: a harmful host that disposes of visiting
agents upon their arrival, leaving no observable trace of such a
destruction. The black hole search problem is the one of
assembling a team of asynchronous mobile agents, executing the
same protocol and communicating by means of whiteboards, to
successfully identify the location of the black hole; we are
concerned with solutions that are generic (i.e., topology-independent).
We establish tight bounds on the size of the team (i.e., the number of agents), and the cost (i.e., the number of moves) of a size-optimal
solution protocol. These bounds depend on the a priori knowledge
the agents have about the network, and on the consistency of the
local labellings. In particular, we prove that: with topological
ignorance agents are needed and suffice, and the cost is
, where is the maximal degree of a node and
is the number of nodes in the network; with topological
ignorance but in presence of sense of direction only agents
suffice and the cost is ; and with complete
topological knowledge only agents suffice and the cost is
. All the upper-bound proofs are constructive
Anticorpi policlonali prodotti nella gallina: un’alternativa all’utilizzo di mammiferi
No full textRIASSUNTO Il problema legato al benessere animale è una questione dai risvolti etici che negli ultimi anni ha notevolmente condizionato la ricerca scientifica coinvolgendo sempre di più alcuni settori della medicina veterinaria. Nei laboratori di ricerca, infatti, si fa spesso uso di animali per la sperimentazione, come nel caso della produzione di anticorpi. Le metodiche impiegate possono talvolta causare sofferenze agli animali e, per questo motivo, da anni sono allo studio metodi alternativi a quelli più frequentemente utilizzati. L’immunizzazione di galline con antigeni di natura proteica consente di ottenere grandi quantità di anticorpi dai tuorli delle uova. Questo tipo di procedura comporta alcuni vantaggi sia dal punto di vista del benessere animale, in quanto scongiura i prelievi ematici per la valutazione del titolo anticorpale dell’animale in vita ed il salasso finale per la raccolta degli anticorpi, sia da quello economico dati i minori costi gestionali rispetto ai mammiferi da laboratorio di medie dimensioni e la maggiore resa finale di anticorpi. In questo lavoro sono stati prodotti anticorpi policlonali nelle galline contro una delle somatotropine bovine ricombinanti (rbST) esistenti in commercio, al fine di operare un confronto con anticorpi policlonali precedentemente prodotti nel coniglio contro la stessa molecola. Il raffronto delle curve ottenute tramite un test ELISA sandwich, messo a punto in precedenza per la quantificazione di bST nel siero e ripetuto utilizzando le due diverse specie anticorpali, ci ha permesso di valutare l’effettiva validità dell’immunizzazione di galliformi per la produzione di grandi quantità di immunoglobuline. SUMMARY Concerns about animal welfare are connected with ethical issues that affect scientific research, involving many veterinary fields. As a matter of facts, animals are often employed for experimental purposes, such as the production of antibodies. Applied methods could sometimes cause suffering to animals and for this reason several studies on alternative methods for antibody production are in progress. Immunisation of hens against proteic antigens allows to obtain a great amount of antibodies from the yolk of treated chicken eggs. This sort of practice brings many advantages for animal welfare, since blood collection is not necessary. In addition, some more advantages come either from the reduced breeding costs with respect to medium-size mammals or the higher antibodies yield. In this work, we have produced polyclonal antibodies in hens against one of the commercialised recombinant bovine somatotropins (rbST), with the aim to make a comparison with rabbit polyclonal antibodies against the same molecule, already produced in an earlier work. With this purpose, we performed a sandwich ELISA previously developed for bST measurement in serum and then compared the curves obtained by using the two different kind of polyclonal antibodies. This allowed us to estimate the worth of poultry immunisation for the production of a great amount of specific antibodies