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Conservazione e valorizzazione del patrimonio architettonico ed ambientale in Belgio
Get PDFLa storia urbana ed architettonica del Belgio è particolarmente legata alle vicende che hanno interessato tutto il territorio soprattutto nei primi anni del XX secolo quando molto forti erano le speranze che venivano riversate sulle innovazioni introdotte prima dall’Art Nouveau e poi dall’ideologia modernista
The deconfining phase transition in full QCD with two dynamical flavors
No full textWe investigate the deconfining phase transition in SU(3) pure gauge theory
and in full QCD with two flavors of staggered fermions. The phase transition is
detected by measuring the free energy in presence of an abelian monopole
background field. In the pure gauge case our finite size scaling analysis is in
agreement with the well known presence of a weak first order phase transition.
In the case of 2 flavors full QCD we find, using the standard pure gauge and
staggered fermion actions, that the phase transition is consistent with weak
first order, contrary to the expectation of a crossover for not too large quark
masses and in agreement with results obtained by the Pisa group
Bottom-up Subtree Isomorphism for Unordered Labeled Trees
No full textA subtree P of a given tree T is a bottom-up subtree of T if, for each internal vertex u of P, all the children of u in T are also vertices of P. Our problem is deciding if a
pattern tree P of m vertices is a bottom-up subtree of a text tree T of n vertices,
m <= n, and, in the affirmative case, finding all the occurrences of P in T. If the vertices are labeled, the labels in the corresponding positions in P and T must match. We consider unordered rooted trees with labeled vertices, which are
reconducted to simpler ordered trees through an ordering algorithm. Processing time depends on the label format. If the labels are single characters of a constant or of an n-integer alphabet \Sigma (respectively, |\Sigma| = constant, or \Sigma is composed of integers in the range [1 \div n]), the problem is solved in
O(m +\log n) time and \Theta(m) additional space, after a preprocessing of T is done in \Theta(n) time and \Theta(n) additional space. The number of occurrences of P in T does not appear in the search time because all such occurrences can be directly reconstructed from a constant output information. For more complex labelsthe running times slightly increase. In particular if the labels are sequences
of characters (e.g. as in XML files) the running time becomes a function of the total length of all the labels in T and P.
Although directed to the "simple problem" of exact subtree matching, our work is the first one to solve it in linear time for unordered trees. Moreover our approach is the one of dictionary search. Regarding as a static text on which several queries are made, as the contents of one such a query, and assuming , the response time for each is sublinear in the size of the overall structure
Predicting Thermodynamic Properties from Molecular Structures by Recursive Neural Networks. Comparison with Classical Group Contributions Methods.
No full textThe recursive neural networks deal with prediction tasks for compounds represented in a structured domain. These approaches allow combining, in a learning system, the flexibility and general advantages of a neural network model with the representational power of a structured domain. As a result a completely new approach to QSPR/QSAR analysis is obtained through the adaptive processing of molecular graphs whose performance is even better than that of traditional approaches. In this paper a Recursive Cascade Correlation model (RecCC) has been applied to the analysis of the Gibbs free energies of solvation in water of 179 monofunctional open chain organic compounds. An original representation of the molecules in terms of labeled directed positional acyclic graphs has been developed by individuating a limited set of constituent atomic groups and representation rules. The descriptive and predictive abilities of the RecCC model have been tested and compared with those of a traditional group contributions method. The inherent ability of the RecCC model to abstract chemical knowledge through the adaptive learning process have been investigated by Principal Components Analysis of the internal representations developed by the neural network, finding that the model recognizes the chemical compounds on the basis of a not trivial combination of their chemical structure and target property
Manipulation of ultracold atomic mixtures using microwave techniques
No full textWe used microwave radiation to evaporatively cool a mixture of of 133Cs and
87Rb atoms in a magnetic trap. A mixture composed of an equal number (around
10^4) of Rb and Cs atoms in their doubly polarized states at ultracold
temperatures was prepared. We also used microwaves to selectively evaporate
atoms in different Zeeman states
Crossover behavior in three-dimensional dilute spin systems
No full textWe study the crossover behaviors that can be observed in the high-temperature
phase of three-dimensional dilute spin systems, using a field-theoretical
approach. In particular, for randomly dilute Ising systems we consider the
Gaussian-to-random and the pure-Ising-to-random crossover, determining the
corresponding crossover functions for the magnetic susceptibility and the
correlation length. Moreover, for the physically interesting cases of dilute
Ising, XY, and Heisenberg systems, we estimate several universal ratios of
scaling-correction amplitudes entering the high-temperature Wegner expansion of
the magnetic susceptibility, of the correlation length, and of the
zero-momentum quartic couplings
SPECT imaging reconstruction through natural pixel discretization
No full textIn this paper the problem of reconstructing a two-dimensional
tomographic medical image is considered. The emission function
is defined on a plane circular domain and
has to be reconstructed from data collected by SPECT. Through the
natural pixel discretization approach the solution is expressed as
a linear combination of functions belonging to a suitable basis.
We consider here four different bases, all of them giving a highly
structured coefficient matrix. By the Fourier transform the linear
system thus obtained can be solved efficiently. The computational
cost and the performance of the bases are compared. The numerical
experimentation shows that when the data are contaminated by
Poissonian noise all the bases are substantially equivalent from
the point of view of the reconstruction efficiency
Infusione continua di detomidina durante chirurgia laparoscopica nel cavallo
No full textRIASSUNTO L’anestesia in stazione quadrupedale è una pratica che permette l’esecuzione di diverse manualità mediche e chirurgiche nel cavallo, senza dover sottoporre il soggetto ai maggiori pericoli di un’anestesia generale. Questa tecnica anestesiologica prevede l’impiego di sedativi in associazione con una tecnica analgesica (somministrazione sistemica, anestesia loco-regionale) qualora la manualità da eseguire comporti l’insorgenza di uno stimolo dolorifico. La laparoscopia prevede l’inserimento intraddominale dei trocar e dello strumentario necessario per eseguire la tecnica. Per evitare danni agli organi da parte dello strumentario in addome, il soggetto deve mantenere una posizione adeguata e non deve effettuare movimenti bruschi. Nello studio è stato formulato un protocollo che ha previsto la sedazione del soggetto mediante la somministrazione di detomidina in associazione con buprenorfina per via endovenosa ed anestesia loco-regionale della porzione interessata dalla chirurgia mediante lidocaina. Per il mantenimento è stata attuata l’infusione endovenosa continua di detomidina con lo scopo di ottenere un livello di sedazione costante nel tempo ed adeguato alla manualità. Infatti la somministrazione di un farmaco per via endovenosa continua permette di variare più rapidamente il livello ematico di questo e, conseguentemente, di poterne modulare gli effetti. La detomidina è un farmaco che produce un accumulo nell’organismo, per cui è stato adottato un protocollo che prevede il dimezzamento il dosaggio dell’infusione ogni quindici minuti. L’impiego di questo protocollo anestesiologico ha permesso di effettuare la procedura laparoscopica senza difficoltà da parte del chirurgo. Il piano analgesico ottenuto è risultato efficace ed adeguato per lo svolgimento della manualità chirurgica. A fine intervento tutti i soggetti hanno ripreso la capacità di deambulare in breve tempo, non presentando complicazioni. SUMMARY Standing horse anesthesia is a practice that allows the execution of medical and surgical techniques, without applying to general anesthesia that is a very stressful and more dangerous event for a horse. In this kind of anesthesia, sedatives are employed in association with an analgesic technique (sistemic analgesia or loco-regional anesthesia) when the practice is supposed to be painful. The abdominal introduction of trocars and of laparoscopic tools is necessary in order to perfom a laparoscopic surgery; for this reason the patient is expected to stand motionless and it is important that it does not make roguh movements during the procedure. The wording of the anesthesia protocol for this study implied the use of detomidine for sedation in association with intravenous buprenorphine as analgesic and loco-regional anesthesia with lidocaine of the surgical area. For the maintenance, detomidine by intravenous continuous infusion was employed with the purpose to obtain a constat sedation level and adequate to the procedure. In fact the constant infusion of drugs permits to change blood concentration more rapidly and consequently it is possible to easily modulate the effects of drugs. Detomidine is a sedative that can accumulate in the organism, so the anesthestic protocol foresaw to halve the dosage every fifteen minutes. This anesthetic protocol provided a good sedation and the laparoscopic technique was performed without problems. The obtained analgesic plan resulted efficacious and adequate for the course of the surgery. At the end of the procedure all the subjects were able rapidly to walk and did not present complications
Tecnica e prospettive di utilizzo della citometria a flusso per la tipizzazione linfocitaria del liquido sinoviale di cane
No full textRIASSUNTO L’utilizzo della citometria a flusso, o fluorimetria, per l’immunofenotipizzazione linfocitaria è una metodica in uso in medicina umana soprattutto nel settore reumatologico, dove riveste un’importanza notevole nella comprensione dei meccanismi degenerativi cartilaginei in corso di artrite reumatoide, mentre è poco utilizzata nella più comune artrosi. In medicina veterinaria la tecnica non è a tutt’oggi utilizzata nella diagnostica collaterale dei problemi ortopedici e reumatologici. Sono disponibili solo due segnalazioni di lavori sperimentali in argomento. Sono state fatte numerose prove su campioni di liquido sinoviale di cane, prelevato sia durante la visita clinica che in sede intraoperatoria, in corso di patologie articolari diverse. Il liquido è stato sottoposto a conta cellulare con contaglobuli elettronico; per essere processato a tal fine e per l’analisi citofluorimetrica, è stato sottoposto a pretrattamento con jaluronidasi. La componente cellulare mononucleata è stata quindi separata e concentrata mediante centrifugazione in gradiente di densità su LymphoprepTM (Ficoll-Isopaque) e studiata con citofluorimetro. Contemporaneamente l’immunofenotipizzazione linfocitaria è stata condotta anche su un campione di sangue periferico. Prove successive finalizzate a rendere il campione un fluido acquoso hanno permesso di evidenziare l’assoluta necessità di pretrattare il campione con 2 gocce di jaluronidasi alla concentrazione di 150UI/ml per 0,25 cc di liquido sinoviale. La quantità di liquido prelevabile è in generale scarsa nei fatti degenerativi cronici, più abbondante nei fenomeni infiammatori acuti, e questo può rappresentare un limite nell’applicazione di questa metodica nella pratica clinica. Per ottenere una buona lettura è necessario avere infatti almeno 1cc di liquido articolare e/o almeno 1000 cellule/μl. La distribuzione delle sottopopolazioni linfocitarie CD3+ e CD21+, ed in particolare del rapporto fra i linfociti CD4+ e CD8+ nel liquido sinoviale e nel sangue, si presenta indicativamente diversa nei fenomeni prevalentemente degenerativi rispetto a quelli squisitamente infiammatori. La tipizzazione linfocitaria nel liquido sinoviale del cane può aprire la strada ad ulteriori indagini per studiare più a fondo i meccanismi eziopatogenetici alla base della condrodegenerazione e della risposta locale e sistemica nei fenomeni osteoartritici e immunitari, oltreché fornire una ausilio nell’individuazione e nel monitoraggio delle terapie. SUMMARY The use of flow cytometry, also called cytofluorimetry, for lymphocyte immunophenotyping is a technique adopted in uman medicine, especially in the rheumatoid field, where is of paramount importance to understand the cartilage degenerative mechanisms during rheumatoid arthritis, while is less used in degenerative joint disease. Till now in veterinary medicine this technique is not included in the ancillary diagnostic methods for orthopaedic and rheumatologic problems. To date only two papers are available about its experimental use. Several tests were done on canine synovial fluid samples, collected during the clinical examination or intraoperatively, in subjects with different joint diseases. The synovial fluid was submit for total cell count with electronic cell-counter; for this purpose and for cytofluorimetric examination too was pre-treated with jaluronidasis. The mononuclear cell phase was then separated and concentrated by centrifugation on LymphoprepTM (Ficoll-Isopaque) and studied with cytofluorimetry. In the mean time the lymphocyte immunophenotyping was performed also on a peripheral blood sample. Further tests aimed to transform the sample in an aqueous fluid has shown the absolute necessity to pre-treat the sample with two drops of jaluronidasis 150 UI/ml in 0,25 cc of synovial fluid. In chronic degenerative joint disease only few drops of synovial fluid can be collected from joints, while more abundant quantities could came from acute inflammatory cases, and this could represent a limit for the applications of the technique in the clinical practice. To perform a good examination we need at least 1cc of synovial fluid and/or at least 1000 cells/μl. Lymphocyte CD3+ and CD21+ subpopulation distribution, and especially CD4+/CD8+ ratio in blood and synovial fluid, shows differences in prevalently degenerative and mainly inflammatory phenomena. The lymphocyte immunophenotyping of canine synovial fluid can represent an alternative instrument to deeply analyze the aetiopathogenetic mechanisms settled at the basis of chondrodegeneration and of the local and systemic response to osteoarthritic and immunological phenomena, and to help in therapeutic choice and monitoring
Epifisiodesi temporanea anteriore del plateau tibiale: una possibile soluzione nella rottura del legamento crociato anteriore in cani in accrescimento
No full textRIASSUNTO Le lesioni del legamento crociato anteriore rappresentano una delle patologie ortopediche più comuni nel cane adulto. L’eziopatogenesi è sempre traumatica, essendo non spesso riferibile a processi degenerativi a carico del legamento, esito di stress cronici conseguenti all’azione della spinta craniale della tibia per effetto del carico ponderale. Nel cucciolo questa patologia è segnalata con minor frequenza, presentandosi tipicamente in forma di avulsione del legamento a livello della sua inserzione tibiale. A differenza del cane adulto, inoltre, questa affezione legamentosa è generalmente di natura traumatica e monolaterale. Qualunque sia l’eziopatogenesi delle lesioni del legamento crociato anteriore, l’intervento chirurgico di stabilizzazione dell’articolazione deve essere effettuato il prima possibile, proponendosi il rallentamento dell’insorgenza e dell’eventuale progressione dei fenomeni osteoartrosici, in particolare nei soggetti in accrescimento. Gli Autori descrivono l’esperienza personale in due cuccioli, di 6 e 5 mesi di età, affetti da rottura traumatica del legamento crociato anteriore e trattati con epifisiodesi anteriore del plateau tibiale. Un soggetto, a seguito della stabilizzazione chirurgica ha presentato un recupero funzionale completo dell’arto operato, come dimostrato dal follow up a distanza di 8 mesi dalla chirurgia. Il secondo cucciolo è stato ripresentato alla visita clinica a distanza di due mesi dall’epifisiodesi, quando ormai il plateau tibiale aveva raggiunto un’inclinazione di 4°, con deviazione in valgo dell’arto. Si è quindi proceduto alla rimozione della vite, con buona ripresa postoperatoria del soggetto, nonostante la persistenza di una saltuaria zoppia di 1° grado. La tecnica decritta ha offerto risultati interessanti, ed ha messo in luce alcune problematiche rappresentate da tempi ridotti di applicabilità della procedura chirurgica e dalla necessità di rimuovere tempestivamente l’interferenza, dovendo intervenire su soggetti ancora in attiva fase d’accrescimento. SUMMARY Cranial cruciate ligament ruptures are one of the most common orthopaedic injury in adult dog. The most frequent cause of cranial cruciate ligament ruptures is, rather than acute trauma, a progressive degeneration consequentely to the intermittent stress of the cranial tibial thrust, elicited by the weight bearing. Cruciate ligament disease is uncommon in puppies, where is usually associated with traumatic injury and avulsion of the cranial cruciate ligament from its tibial site of attachment. Surgery should be performed in a very short time, in order to slow and prevent degenerative joint diseases, particularly in younger dogs. The Authors report their clinical experience about 2 puppies affected by traumatic cranial cruciate ligament injury, 6 and 5 months old respectively, treated with cranial epiphysiodesis of the tibial plateau. One dog had a successful recovery in a short time after joint stabilization, as observed at an 8 months follow up. The other puppy was revisited after 2 months from surgery, when tibial plateau slope amount was 4°; the affected leg presented a valgus deviation, too. Then, the puppy underwent on surgery for the screw remotion showing a satisfactory recovery, even though an occasional lameness persists. Epiphysiodesis offered interesting results and shows some complications such as the short range of puppies’age in wich surgery can be performed and the need to remove the interference as soon as possible, in order not to interfere with growing process