668 resultados para Orientamento di Grafi, Ricerca Operativa, CPLEX


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Questo lavoro di tesi nasce da un progetto di ricerca promosso nel 2001 dal Prof. Leonardo Seccia (Seconda Facoltà di Ingegneria, sede di Forlì, e C.I.R.A.M., Università di Bologna), dal Prof. Nicola Santopuoli (Facoltà di Architettura Valle Giulia, Sapienza Università di Roma), dal Prof. Ingo Muller e dal Dott. André Musolff (Technical University Berlin, Facultat III, Thermodynamics). Tale progetto ha avuto come obiettivo lo studio, la progettazione e la realizzazione di un dispositivo di ancoraggio in lega a memoria di forma per il restauro di affreschi e mosaici parietali, che presentino distacchi più o meno evidenti fra gli strati di intonaco di supporto, proponendosi come mezzo efficace per la salvaguardia strutturale di tali zone variamente ammalorate. In particolare, è stata programmata una serie di prove di laboratorio per caratterizzare in modo preciso il comportamento del materiale prescelto, al fine di realizzare un prototipo rispondente alle caratteristiche di progetto ed anche per implementare un modello numerico sufficientemente realistico. A questo proposito, è stato anche approfondito il problema della scelta del modello costitutivo più adeguato. Successivamente, i risultati ottenuti sono stati impiegati nella progettazione e realizzazione di nuovi dispositivi in lega a memoria di forma da impiegare nel campo dei beni culturali, fra cui sistemi reversibili per il ricongiungimento di parti fratturate e sistemi di movimentazione intelligenti sia per lastre di protezione di superfici affrescate, sia per finestre da inserire in contesti museali per il controllo del microclima.

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Recent developments in piston engine technology have increased performance in a very significant way. Diesel turbocharged/turbo compound engines, fuelled by jet fuels, have great performances. The focal point of this thesis is the transformation of the FIAT 1900 jtd diesel common rail engine for the installation on general aviation aircrafts like the CESSNA 172. All considerations about the diesel engine are supported by the studies that have taken place in the laboratories of the II Faculty of Engineering in Forlì. This work, mostly experimental, concerns the transformation of the automotive FIAT 1900 jtd – 4 cylinders – turbocharged – diesel common rail into an aircraft engine. The design philosophy of the aluminium alloy basement of the spark ignition engine have been transferred to the diesel version while the pistons and the head of the FIAT 1900 jtd are kept in the aircraft engine. Different solutions have been examined in this work. A first V 90° cylinders version that can develop up to 300 CV and whose weight is 30 kg, without auxiliaries and turbocharging group. The second version is a development of e original version of the diesel 1900 cc engine with an optimized crankshaft, that employ a special steel, 300M, and that is verified for the aircraft requirements. Another version with an augmented stroke and with a total displacement of 2500 cc has been examined; the result is a 30% engine heavier. The last version proposed is a 1600 cc diesel engine that work at 5000 rpm, with a reduced stroke and capable of more than 200 CV; it was inspired to the Yamaha R1 motorcycle engine. The diesel aircraft engine design keeps the bore of 82 mm, while the stroke is reduced to 64.6 mm, so the engine size is reduced along with weight. The basement weight, in GD AlSi 9 MgMn alloy, is 8,5 kg. Crankshaft, rods and accessories have been redesigned to comply to aircraft standards. The result is that the overall size is increased of only the 8% when referred to the Yamaha engine spark ignition version, while the basement weight increases of 53 %, even if the bore of the diesel version is 11% lager. The original FIAT 1900 jtd piston has been slightly modified with the combustion chamber reworked to the compression ratio of 15:1. The material adopted for the piston is the aluminium alloy A390.0-T5 commonly used in the automotive field. The piston weight is 0,5 kg for the diesel engine. The crankshaft is verified to torsional vibrations according to the Lloyd register of shipping requirements. The 300M special steel crankshaft total weight is of 14,5 kg. The result reached is a very small and light engine that may be certified for general aviation: the engine weight, without the supercharger, air inlet assembly, auxiliary generators and high pressure body, is 44,7 kg and the total engine weight, with enlightened HP pump body and the titanium alloy turbocharger is less than 100 kg, the total displacement is 1365 cm3 and the estimated output power is 220 CV. The direct conversion of automotive piston engine to aircrafts pays too huge weight penalties. In fact the main aircraft requirement is to optimize the power to weight ratio in order to obtain compact and fast engines for aeronautical use: this 1600 common rail diesel engine version demonstrates that these results can be reached.

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Beet soil-borne mosaic virus (BSBMV) and Beet necrotic yellow vein virus (BNYVV) are members of Benyvirus genus. BSBMV has been reported only in the United States while BNYVV has a worldwide distribution. Both viruses are vectored by Polymyxa betae, possess similar host ranges, particles number and morphology. Both viruses are not serologically related but have similar genomic organizations. Field isolates consist of four RNA species but some BNYVV isolates contain a fifth RNA. RNAs 1 and 2 are essential for infection and replication while RNAs 3 and 4 play important roles on plant and vector interactions, respectively. Nucleotide and amino acid analyses revealed BSBMV and BNYVV are different enough to be classified in two different species. Additionally in BNYVV/BSBMV mixed infections, a competition was previous described in sugar beet, where BNYVV infection reduces BSBMV accumulation in both susceptible and resistant cultivars. Considering all this observations we hypothesized that BNYVV and BSBMV crossed study, exploiting their similarities and divergences, can improve investigation of molecular interactions between sugar beets and Benyviruses. The main achievement of our research is the production of a cDNA biologically active clones collection of BNYVV and BSBMV RNAs, from which synthetic copies of both Benyviruses can be transcribed. Moreover, through recombination experiments we demonstrated, for the first time, the BNYVV RNA 1 and 2 capability to trans-replicate and encapsidate BSBMV RNA 3 and 4, either the BSBMV RNA 1 and 2 capability to replicate BNYVV RNA2 in planta. We also demonstrated that BSBMV RNA3 support long-distance movement of BNYVV RNA 1 and 2 in B. macrocarpa and that 85 foreign sequence as p29HA, GFP and RFP, are successfully expressed, in C. quinoa, by BSBMV RNA3 based replicon (RepIII) also produced by our research. These results confirm the close correlation among the two viruses. Interestingly, the symptoms induced by BSBMV RNA-3 on C. quinoa leaves are more similar to necrotic local lesions caused by BNYVV RNA-5 p26 than to strongly chlorotic local lesions or yellow spot induced by BNYVV RNA- 3 encoded p25. As previous reported BSBMV p29 share 23% of amino acid sequence identity with BNYVV p25 but identity increase to 43% when compared with sequence of BNYVV RNA-5 p26. Based on our results the essential sequence (Core region) for the longdistance movement of BSBMV and BNYVV in B. macrocarpa, is not only carried by RNA3s species but other regions, perhaps located on the RNA 1 and 2, could play a fundamental role in this matter. Finally a chimeric RNA, composed by the 5’ region of RNA4 and 3’ region of RNA3 of BSBMV, has been produced after 21 serial mechanically inoculation of wild type BSBMV on C. quinoa plants. Chimera seems unable to express any protein, but it is replicated and transcript in planta. It could represent an important tool to study the interactions between Benyvirus and plant host. In conclusion different tools, comprising a method to study synthetic viruses under natural conditions of inoculum through P. Betae, have been produced and new knowledge are been acquired that will allow to perform future investigation of the molecular interactions between sugar beets and Benyviruses.

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In the era of monoclonal antibodies the role of autologous stem cell transplantation (ASCT) in the management of follicular lymphoma (FL) is still debated. To evaluate the safety and efficacy of myeloablative therapy with rescue of purged or unpurged harvests in FL pts. At our institution form 1997 to 2007 28 pts with refractory/resistant FL were eligible for ASCT. Before high dose therapy they received 2-3 cycles of CHOP-like regimen (ACOD), followed by Cyclophosphamide 4g/mq to mobilize the stem cells (SC). After SC collection the pts underwent 3 cycles of subcutaneous Cladribine at a daily dose of 0,14-0,10 mg/Kg for Day 1-5 every 3-4 weeks. The conditioning regimen was based on Mitoxantrone 60mg/mq + Melphalan 180 mg/mq, followed by SC re-infusion 24-hours later and G-CSF starting 24 hours after re-infusion. In 19 pts the SC underwent purging: in 10 harvests the CD34+ were selected by immunomagnetic beads, while in the other 9 pts, only Rituximab was used as “purging in vivo” agent. The remaining 9 pts received unpurged SC. Before ASCT 11 pts were in complete response (CR), 9 in partial response (PR) and 2 in stable disease. Two pts were not eligible for ASCT because of progressive disease (PD). The remaining 25 pts were eligible for ASCT. The engraftment was at a median of 11 days for leucocytes and 14 days for platelets (>20.000/mmc), with a delay of one day in the pts, who received purged SC. Grade 3-4 mucositis was described in 8 pts. During aplasia a 48% infection rate was reported, without differences between pts with purged or unpurged SC. One patient in CR presented myelodysplastic syndrome at 18 months from ASCT. After ASCT 22 pts were in CR, 2 in PR and one patient were not valuable, because died before response assessment. Nine pts in CR showed PD at a median time of 14 months from ASCT. With a median follow up of 5 years (range 2 months -10 years), 22 pts are alive and 11 (44%) in CR. Ten pts died, 5 for progressive disease and 5 for treatment-related causes; in particular 7 of them received in-vitro purged SC. Conclusions: Our chemotherapy regimen, which included the purine analogue Cladribine in the induction phase, seems safe and feasible. The high rate of CR reported and the sustained freedom from progression up to now, makes such modality of treatment a valid option principally in relapsing FL patients. In our experience, the addition of a monoclonal antibody as part of treatment confirms its role “in vivo purging” without observing an increased incidence of infection.

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L’argomento della presente tesi di dottorato riguarda lo studio clinico del trapianto di cellule staminali emopoietiche aploidentiche nelle patologie oncoematologiche. Nel periodo di tempo compreso tra 1/12/2005 ed il 30/10/2007 sono stati arruolati 10 pazienti (6 LAM, 3 LAL, 1 LMC in crisi blastica mieloide) nell’ambito di uno studio clinico che prevedeva il trapianto di midollo osseo aploidentico per pazienti affetti da patologia oncoematologica in prima o successiva recidiva, per i quali non fosse disponibile un donatore di midollo osseo consanguineo o da banca. Lo schema di condizionamento al trapianto di midollo osseo utilizzato era il seguente: Fludarabina 150/m2, Busulfano orale 14mg/kg, Tiothepa 10mg/kg e Ciclofosfamide 160mg/kg. Per la profilassi della malattia da trapianto contro l’ospite è stata somministrata timoglobulina antilinfocitaria (ATG) al dosaggio complessivo di 12.5 mg/kg, short course metotrexate (+1, +3 e +11), cortisone e ciclosporina con tapering precoce al + 60. I pazienti hanno reinfuso una megadose di cellule CD34+ mediana pari a 12.8x106/kg. Tre pazienti non sono valutabili per l’attecchimento a causa di rigetto (1/3) o morte precoce (2/3). Sette pazienti sono valutabili per l’attecchimento; per questi pazienti il tempo mediano a 500 PMN/mmc e a 20 x 109/l piastrine è stato rispettivamente di 17 e 20 giorni. Quattro pazienti su 7 hanno svillupato una Graft versus Host Disease (GVHD) acuta di grado II-IV, mentre soltanto 1/7 ha sviluppato una GVHD cronica. Sette pazienti su 10 trapiantati hanno ottenuto una remissione completa successivamente al trapianto. Di questi, attualmente 2 pazienti sono vivi in remissione completa, mentre gli altri 5 sono ricaduti e successivamente deceduti. In conclusione, il trapianto aploidentico è una procedura fattibile ed efficace. Tale procedura è in grado di garantire un 20% di lungo sopravviventi in un setting di pazienti a prognosi estremamente infausta.

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L’infezione da virus dell’ epatite E (HEV) nei suini e nell’uomo è stata segnalata in diversi Paesi. Nei suini, il virus causa infezioni asintomatiche, mentre nell’uomo è responsabile di epidemie di epatite ad andamento acuto nei Paesi a clima tropicale o subtropicale con condizioni igieniche scadenti, di casi sporadici in quelli sviluppati. HEV è stato isolato anche in diversi animali e l’analisi nucleotidica degli isolati virali di origine animale ha mostrato un elevato grado di omologia con i ceppi di HEV umani isolati nelle stesse aree geografiche, avvalorando l’ipotesi che l'infezione da HEV sia una zoonosi. In America del Sud HEV suino è stato isolato per la prima volta in suini argentini nel 2006, mentre solo dal 1998 esistono dati sull’ infezione da HEV nell’uomo in Bolivia. In questa indagine è stato eseguito uno studio di sieroprevalenza in due comunità rurali boliviane e i risultati sono stati confrontati con quelli dello studio di sieroprevalenza sopra menzionato condotto in altre zone rurali della Bolivia. Inoltre, mediante Nested RT-PCR, è stata verificata la presenza di HEV nella popolazione umana e suina. La sieroprevalenza per anticorpi IgG anti-HEV è risultata pari al 6,2%, molto simile a quella evidenziata nello studio precedente. La prevalenza maggiore (24%) si è osservata nei soggetti di età compresa tra 41 e 50 anni, confermando che l’ infezione da HEV è maggiore fra i giovani-adulti. La ricerca di anticorpi anti HEV di classe IgM eseguita su 52 sieri ha fornito 4 risultati positivi. Il genoma virale è stato identificato in uno dei 22 pool di feci umane e l'esame virologico di 30 campioni individuali fecali e 7 individuali di siero ha fornito rispettivamente risultati positivi in 4/30 e 1/7. La Nested RT-PCR eseguita sui 22 pool di feci suine ha dato esito positivo in 7 pool. L’analisi delle sequenze genomiche di tutti gli amplificati ha consentito di stabilire che gli isolati umani appartenevano allo stesso genotipo III di quelli suini e presentavano con questi una elevata omologia aminoacidica (92%).

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From September 2005 to December 2006, in order to define the prevalence of Helicobacter pullorum in broiler chickens, laying hens and turkey, a total of 365 caecum contents of animals reared in 76 different farms were collected at the slaughterhouse. A caecum content of a ostrich was also sampled. In addition, with the aim of investigating the occurrence of H. pullorum in humans, 151 faeces were collected at the Sant’Orsola-Malpighi University Hospital of Bologna from patients suffering of gastroenteritis. A modified Steele–McDermott membrane filter method was used. Gram-negative curved rod bacteria were preliminary identified as H. pullorum by a PCR assay based on 16S rRNA, then subjected to a RFLP-PCR assay to distinguish between H. pullorum and H. canadensis. One isolate from each farm was randomly selected for phenotypic characterization by biochemical methods and 1D SDSPAGE analysis of whole cell proteins profiles. Minimum Inhibitory Concentration (MIC) for seven different antibiotics were also determined by agar dilution method. Moreover, to examine the intraspecific genomic variability, two strains isolated from 17 different farms were submitted to genotyping by Pulse-Field Gel Electrophoresis (PFGE). In order to assess the molecular basis of fluorquinolone resistance in H. pullorum, gyrA of H. pullorum CIP 104787T was sequenced and nucleotide sequences of the Quinolone Resistance Determining Region (QRDR) of a total of 18 poultry isolates, with different MIC values for ciprofloxacin and nalidixic acid, were compared. According to the PCR and PCR-RFLP results, 306 out of 366 animals examined were positive for H. pullorum (83,6%) and 96,1% of farms resulted infected. All positive samples showed a high number of colonies (>50) phenotipically consistent with H. pullorum on the first isolation media, which suggests that this microrganism, when present, colonizes the poultry caecum at an elevate load. No human sample resulted positive for H. pullorum. The 1D SDS-PAGE whole protein profile analysis showed high similarity among the 74 isolates tested and with the type strain H. pullorum CIP 104787T. Regarding the MIC values, a monomodal distribution was found for ampicillin, chloramphenicol, gentamicin and nalidixic acid, whereas a bimodal trend was noticed for erythromycin, ciprofloxacin and tetracycline (indicating an acquired resistance for these antibiotics). Applying the breakpoints indicated by the CSLI, we may assume that all the H. pullorum tested are sensitive only to gentamicin. The intraspecific genomic variability observed in this study confirm that this species don’t have a clonal population structure, as motioned by other autors. The 2490 bp gyrA gene of H. pullorum CIP104787T with an Open Reading Frame (ORF) encoding a polypeptide of 829 amino acids was for the first time sequenced and characterized. All ciprofloxacin resistant poultry isolates showed ACA®ATA (Thr®Ile) substitution at codon 84 of gyrA corresponding to codons of gyrA 86, 87 and 83 of the Campylobacter jejuni, H. pylori and Escherichia coli, respectively. This substitution was functionally confirmed to be associated with the ciprofloxacin resistant phenotype of poultry isolates. This is the first report of isolation of H. pullorum in turkey and in ostrich, indicating that poultry species are the reservoir of this potential zoonotic microorganisms. In order to understand the potential role as food-borne human pathogen of H. pullorum, further studies must be carried on.

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Background: Several lines of evidence showed that inflammation is associated with changes in the expression of tachykinins both in human and animal models. Tachykinins, including substance P (SP), are small peptides expressed in the extrinsic primary afferent nerve fibres and enteric neurons of the gut: they exert their action through three distinct receptors, termed NK1, NK2 and NK3. SP modulates intestinal motility and enteric secretion, acting preferentially through the NK1 receptor. SP neural network and NK1 receptor expression are increased in patients with inflammatory bowel disease, and similar changes were observed in experimental models of inflammation. The 2,4 Dinitrobenzene Sulphonic Acid (DNBS) model of colitis is useful to study innate immunity, non-specific inflammation and wound healing; it has been suggested that the transmural inflammation seen in this model resembles that found in Crohn’s disease and can therefore be used to study what cells and mediators are involved in this type of inflammation. Aim: To test the possible protective effect of the NK1 receptor antagonist SSR140333 on: 1) acute model of intestinal inflammation; 2) reactivation of DNBS-induced colitis in rats. Methods: Acute colitis was induced in male SD rats by intrarectal administration of DNBS (15 mg/rat in 50% ethanol). Reactivation of colitis was induced by intrarectal injections of DNBS on day 28 (7.5 mg/rat in 35% ethanol). Animals were sacrificed on day 6 (acute colitis) and 29 (reactivation of colitis). SSR140333 (10 mg/kg) was administered orally starting from the day before the induction of colitis for 7 days (acute colitis) or seven days before the reactivation of colitis. Colonic damage was assessed by means of macroscopic and microscopic scores, myeloperoxidase activity (MPO) and TNF-α tissue levels. Enzyme immunoassay was used to measure colonic substance P levels. Statistical analysis was performed using analysis of variance (one-way or two-way, as appropriate) with the Bonferroni’s correction for multiple comparisons. Results: DNBS administration impaired body weight gain and markedly increased all inflammatory parameters (p<0.01). Treatment with SSR140333 10 mg/kg significantly counteracted the impairment in body weight gain, decreased macroscopic and histological scores and reduced colonic myeloperoxidase activity (p<0.01). Drug treatment counteracted TNF-α tissue levels and colonic SP concentrations (acute model). Similar results were obtained administering the NK1 receptor antagonist SSR140333 (3 and 10 mg/kg) for 5 days, starting the day after the induction of colitis. Intrarectal administration of DNBS four weeks after the first DNBS administration resulted in reactivation of colitis, with increases in macroscopic and histological damage scores and increase in MPO activity. Preventive treatment with SSR140333 10 mg/kg decreased macroscopic damage score, significantly reduced microscopic damage score but did not affect MPO activity. Conclusions: Treatment with SSR140333 significantly reduced intestinal damage in acute model of intestinal inflammation in rats. The NK1 receptor antagonist SSR140333 was also able to prevent relapse in experimental colitis. These results support the hypothesis of SP involvement in intestinal inflammation and indicate that NK receptor antagonists may have a therapeutic potential in inflammatory bowel disease.

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For a long time, the work of a Franciscan Friar who had lived in Bologna and in Florence during the 13th and 14th centuries, Bartolomeo Della Pugliola, was thought to have been lost. Recent paleographic research, however, has affirmed that most of Della Pugliola’s work, although mixed into other authors, is contained in two manuscripts (1994 and 3843), currently kept at University Library in Bologna. Pugliola’s chronicle is central to Bolognese medieval literature, not only because it was the privileged source for the important work of Ramponis’ chronicle, but also because Bartolomeo della Pugliola’s sources are several significant works such as Jacopo Bianchetti’s lost writings and Pietro and Floriano Villolas’ chronicle (1163-1372). Ongoing historical studies and recent discoveries enabled me to reconstruct the historical chronology of Pugliola’s work as well as the Bolognese language between the 13th and 14th century The original purpose of my research was to add a linguistic commentary to the edition of the text in order to fill the gaps in medieval Bolognese language studies. In addition to being a reliable source, Pugliola’s chronicle was widely disseminated and became a sort of vulgate. The tradition of chronicle, through collation, allows the study of the language from a diachronic point of view. I therefore described all the linguistics phenomena related to phonetics, morphology and syntax in Pugliola’s text and I compared these results with variants in Villola’s and Ramponis’ chronicles. I also did likewise with another chronicle by a 16th century merchant, Friano Ubaldini, that I edited. This supplement helped to complete the Bolognese language outline from the 13th to the 16th century. In order to analize the data that I collected, I tried to approach them from a sociolinguistic point of view because each author represents a different variant of the language: closer to a scripta and the Florentine the language used by Pugliola, closer to the dialect spoken in Bologna the language used by Ubaldini. Differencies in handwriting especially show the models the authors try to reproduce or imitate. The glossary I added at the end of this study can help to understand these nuances with a number of examples.