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La responsabilita' del magistrato da "interpretazione anticomunitaria"
Get PDFCAPITOLO PRIMO\ud
LA VICENDA GIUDIZIALE CHE HA CONSACRATO UNA NUOVA IPOTESI DI ILLECITO ELABORATA DALLA GIURISPRUDENZA COMUNITARIA\ud
1. L'occasione dell'analisi. Genesi della vicenda giudiziaria: la causa Traghetti del Mediterraneo s.p.a. contro Tirrenia s.p.a. nei primi due gradi di giudizio in Italia.\ud
2. Il casus belli: la vicenda giunge alla Suprema Corte. La sentenza della Corte di Cassazione del 19 aprile 2000, n. 5087.\ud
3. Il ricorso al Tribunale di Genova per la domanda di risarcimento danni arrecato alla soccombente dal decisum della Cassazione.\ud
4. La sentenza della Corte di Giustizia, Grande Chambre, 13 giugno 2006, causa c-173/03, Traghetti del Mediterraneo s.p.a. in liquidazione, c. Repubblica Italiana.\ud
CAPITOLO SECONDO\ud
FONDAMENTO DELLA RESPONSABILITA' DELLO STATO PER FATTO DELL'ORGANO GIUDIZIARIO NELL'OTTICA COMUNITARIA\ud
1. Il dovere di interpretazione comunitariamente conforme\ud
2. Il principio di primauté du droit communautaire\ud
3. La funzione "nomofilattica" della Corte di Giustizia\ud
4. Il ruolo "maieutico" della Corte di Giustizia: principi comunitari e principi comuni agli Stati membri\ud
5. Lo schema della responsabilita' extra-contrattuale nel diritto comunitario: l'art. 288 TCE e i principi in materia comuni agli Stati membri\ud
6. I presupposti della responsabilita' civile dello Stato per violazione del diritto comunitario: dalla sentenza Francovich alla Traghetti.\ud
7. Il rapporto tra la violazione "manifesta" ed il sistema italiano di responsabilita' per colpa\ud
8. L'art. 234, III comma, TCE e l'obbligo di rinvio pregiudiziale che incombe sugli organi giudiziali interni "di ultima istanza”\ud
9. La sentenza della Corte di Giustizia, 30 settembre 2003, Koebler c. Repubblica austriaca\ud
CAPITOLO TERZO\ud
FONDAMENTO DELLA RESPONSABILITA' DELLO STATO E DEL MAGISTRATO NELL'OTTICA INTERNA\ud
1. La soggezione del Giudice alla legge: gli artt. 101 e 117 cost.\ud
2. Il peso dei principi comunitari in una nuova lettura dell'art. 12 delle preleggi.\ud
3. Il dovere del magistrato di tentare un'interpretazione comunitariamente orientata della legge. Il ruolo del giudice ed il suo rapporto con l'art. 234, II comma, TCE.\ud
4. Lo strumento della disapplicazione della legge\ud
5. Il ruolo della Corte Costituzionale ed il suo rapporto con l'art. 234 TCE\ud
6. Interpretazione della legge e sindacato di costituzionalita': potere del giudice. Interpretazione della legge "comunitariamente orientata": dovere del giudice. Diversa rilevanza del potere di controllo.\ud
CAPITOLO QUARTO\ud
STRUTTURA DELL'ILLECITO DEL MAGISTRATO NEL SISTEMA DI RESPONSABILITA' CIVILE ITALIANO: La Legge 13 aprile 1988, n. 177\ud
1. Fondamento e struttura dell'illecito di cui alla Legge 177/88: la clausola di esenzione dell'attivita' interpretativa del giudice.\ud
2. L'elemento soggettivo: "dolo o colpa grave”\ud
3. La "colpa grave" e l'esigibilita' della conoscenza del diritto comunitario.\ud
Il principio iura novit curia e responsabilita' professionale del magistrato: parallelismi con il sistema di cui alla Legge 218/1995\ud
4. I requisiti della "negligenza inescusabile" richiesta dalla normativa interna della "violazione manifesta" prevista dalla giurisprudenza comunitaria: possibile equivalenza.\ud
5. Il magistrato responsabile come ogni professionista ex art. 2236 c.c. in un'ottica comunitaria: una questione aperta.\ud
6. La Suprema Corte dinanzi all'applicazione della L. 177/88 resta dopo la sentenza Traghetti: le pronunce della Corte di Cassazione, Sez. Terza, del 5 luglio 2007, n. 15227 e del 18 marzo 2008, n. 7272.\ud
7. Ipotizzabilita' dell'impiego dell'interpretazione comunitariamente conforme quale strumento parzialmente conservativo della Legge 177/88. L'auspicio di un revirement .\ud
CAPITOLO QUINTO\ud
CENNI DI PROFILI PROBLEMATICI DEL GIUDIZIO DOMESTICO RISARCITORIO VERSO LO STATO ED IL MAGISTRATO\ud
1. Sull'esistenza di un diritto del cittadino a un' "interpretazione comunitariamente orientata"\ud
2. La disciplina applicabile al giudizio interno: il modello della responsabilita' aquiliana ex art. 2043 c.c.\ud
3. In particolare: il fatto contra ius et non iure. La non discrezionalita' interpretativa, il mancato rinvio ed il problema della configurabilita' di un illecito meramente omissivo\ud
4. Il rapporto tra Stato e magistrato: l'art. 28 cost.\ud
5. L'azione di rivalsa dello Stato verso il magistrato.\u
Sulfur-metal interactions in silicate glasses studied by x-ray spectroscopy
No full textVolcanoes release to the atmosphere large amounts of S gases that influence the backscatter of solar radiation through the formation of sulfate aerosols. In recent years,\ud
several large volcanic eruptions in subduction-zone settings (Mount Pinatubo, Philippines; El Chichon, Mexico; Lascar, Chile) have produced abnormally large amounts of gaseous SO2 (Carroll and Rutherford, 1987). For instance, the Mount Pinatubo explosive eruption in 1991, discharged into the atmosphere millions of tons of sulfur dioxide, resulting in a decrease in the temperature worldwide for several years. The large sulfur emissions accompanying the eruption of these relatively oxidized magmas (high oxygen fugacity) have prompted new efforts to study the influence of volcanic gas emissions on the Earth's climate. The sulfur gaseous emission of a volcano depends largely on the initial S content of the magma and then on the S solubility in the same magma. Solubility, in turn, depends on temperature, pressure as well as the chemical composition and oxygen fugacity of the magma. All these factors affect the chemical state of sulfur and thus its solubility in the\ud
magma.\ud
In this study the chemical behaviour of sulfur in minerals and glasses was widely investigated via X-ray Absorption Near Edge Structure (XANES) spectroscopy, which probes the unoccupied density of states and thus provides information on the oxidation state and local structure of the species under study. However, the XANES spectral shape is\ud
influenced by various effects, namely the local symmetry, the ligand type, even up to high coordination spheres, and the valence electron occupation, making in some cases difficult to systematically analyze the different spectral contributions. Therefore here we used X-ray Emission Spectroscopy (XES) as a complementary technique to avoid some of the inherent difficulties of XANES analysis, and to extract additional information on the electronic structure.\ud
The Kbeta lines, close to the K-edge, directly yield the p-density of occupied valence states, giving valuable information on the local coordination. We compared XANES and\ud
Kbeta XES experimental data on sulfur-bearing minerals with ab-initio quantum-chemical calculations based on density functional theory (DFT), in order to visualize the molecular\ud
orbitals and to extract information about the chemical bonding in these compounds. The S Kalpha emission lines, which arise from 2p to 1s transitions, are expected to be mostly free from chemical bond effects except for small energy shifts that reflect the valence orbital\ud
electron population via screening effects. S Kalpha shifts can be readily used to determine the speciation of sulfur in silicate glasses. The electronic configuration of the sulfur atoms was obtained by calculating the effective charge around the sulfur atom based on the Mulliken\ud
population analysis generated by DFT calculations, and then successfully correlated with the observed experimental shifts. In order to check these results using a theoretical\ud
framework other than DFT, we also performed calculations using a multiple-scatteringapproach (FEFF 8.4).\ud
X-ray absorption and emission spectroscopies were applied to the study of rhyolitic obsidians from the Kenya Rift Valley. The natural glasses, melted and treated in the lab at different redox conditions and temperatures have different compositions, each with different alkali/alumina ratios ((Na2O + K2O)/Al2O3), also known as peralkalinity. Scaillet and McDonald (2006) reported a strong dependency of sulfur solubility on their peralkaline in the same set of glasses, however in order to understand the role of sulfur in these systems, information on the geochemical behavior of sulfur is needed. The speciation of sulfur in the glasses, oxidation state and local geometry, was analyzed comparatively by XAS and XES. The behavior of sulfur in the three series was accurately determined by\ud
using the energy shift of the S K emission lines, which allowed also to make a quantitative determination of the sulfur species. We observed that we can follow the\ud
evolution of sulfur as a function of controlled formation conditions with respect to pressure, temperature or oxygen fugacity, and determine whether it is present as sulfate or\ud
sulfide. No sulfite species have been detected. XANES and Kbeta emission lines also yield detailed information on the local chemistry and structure, and thus help us to understand the geochemical role of S in these systems. In particular we were able to identify the presence of iron in a coordination geometry similar to pyrrhotite as the sulfur ligand in reduced glasses.\ud
Furthermore, we investigated the coordination and redox state of iron in the two most peralkaline series of glasses by means of Fe K-edge XANES. By the analysis of the\ud
pre-edge and comparison with characterized mineral standards, we found fundamental differences in the coordination and chemical state of iron depending on redox state and glass bulk composition. The observed variations in iron oxidation state and average coordination in these glasses have been tentatively explained by observing that the oxygen fugacity, as expected, produces the oxidation of iron and therefore, decreases the quantity of Fe2+ available for coordinating with S2-. Also there is a relationship between the increased content of Fe3+ and the alkalis amount in the glass. The data suggest that large\ud
amounts of divalent iron present in the glass can stabilize the sulfide phase, explaining the unusual high sulfur solubility in strongly peralkaline silicate glasses at low oxygen fugacity conditions. Instead, the sulfur solubility saturation observed at high oxygen fugacity conditions may be explained by an oxy-reduction interaction between sulfur and iron.\ud
\u
Effects and tolerability of endovenous administered tramadol in horses
No full textControl of painful conditions is becoming an increasingly important part of veterinary medicine. Many of the available analgesics are considered effective for a variety of painful conditions in horses, but their use may be limited for various reasons. The development of unwanted side effects are a major factor that limits their use. Tramadol has only recently gained significant attention as an analgesic in animals despite its having been used in humans in Germany since 1977.\ud
Tramadol hydrochloride, (1RS,2RS)-2-[(dimethylamino)-methyl]-1-(3-methoxyphenyl)-cyclohexanol hydrocloride, is a centrally acting analgesic that has been used clinically for the two decades to treat acute and chronic pain in humans. Tramadol produces its antinociceptive effect in animals and analgesic effect in humans by both opioid and non-opioid mechanism of action. Tramadol is available as a racemic mixture composed of (+) and (-) enantiomers in equal proportions. The racemic mixture produces analgesia by synergistic action of two enantiomers and their main O-desmethylated metabolites (M1). In fact (+)M1 has been demonstrated to have an affinity to µ-opioid receptors that is 200 times greater than that of the parent compound. On the other hand, the monoaminergic component in tramadol analgesia is mediated by (-)tramadol, by means of an inhibition of the re-uptake of the neurotransmitters serotonina and norepinephrine. The therapeutic use of tramadol has not been associated with significant adverse effects, such as respiratory depression, constipation or sedation, and the drug has been used successfully in humans and many animals to produce analgesia in peri-operative and post-operative periods. \ud
The pharmacokinetics of tramadol have been investigated in several animal species and recently also in horse. After IV administration at a dose of 2.0 mg/kg in only two horses muscle twitching were observed and physical examination revealed decreased gastrointestinal sounds. Moreover, there are two studies that showed good analgesic effect after epidural administration of tramadol to horses without any significant influence on heart rate, respiratory rate, arterial blood pressure, body temperature and behaviour. Caudal epidural administration of tramadol was compared with morphine and both are potential drugs in management of perineal and lumbosacral pain in horse \ud
The purpose of this study was to investigate the effects and tolerability of systemically administered tramadol at two different dosages (1.0 mg/kg EV and 2.0 mg/kg EV) in the horse. Heart rate, respiratory rate, arterial blood pressure, body temperature, central nervous system excitement, head ptosis, arterial pH, PaO2 and PaCO2 were measured during 12-hour period and the different was statistically evaluated. Analgesia was not documented.\ud
Results of this study suggest that tramadol con be administered to horse systematically at a dose of 2.0 mg/kg.\u
Fractal analysis of granular materials and its application to geological phenomena
No full textIn this work, after a brief presentation of fractal sets and their geometrical properties, we have introduced the concept of Hausdorff measure and Hausdorff dimension.\ud
Afterwards, we have calculated the fractal dimension of the stress produced by different granular materials under static conditions, compressive stress and shear stress in a silo. Finally, we have showed some applications to geological phenomena.\ud
\ud
\ud
CHAPTER ONE - Hausdorff measure and dimension pag.2\ud
1.1 Hausdorff measure pag. 2\ud
1.2 Hausdorff dimension pag. 6\ud
1.3 Calculation of Hausdorff dimension pag. 9\ud
1.4 Equivalent definitions of Hausdorff dimension pag.12\ud
1.5 Lebesgue measure on pag.14\ud
1.6 Lebesgue measure on pag. 14\ud
CHAPTER TWO - Geometrical properties of fractal sets pag.16\ud
2.1 Basic set theory pag 16\ud
2.2 Functions and limits pag 21.\ud
2.3 Self-similar sets pag.27\ud
2.4 Cantor set pag.32\ud
2.5 Von Koch curve pag.34\ud
2.6 Sierpinsky triangle pag.37\ud
2.7 Osculatory and apollonian packings pag. 39\ud
2.8 Julia sets pag.43\ud
CHAPTER THREE - Probability theory and s-independence pag.49\ud
3.1 Notes on probability theory pag.49\ud
3.2 S-independence respect to upper and lower conditional\ud
probabilities assigned by Hausdorff outer and inner measures pag.58\ud
3.3 Conclusions and applications pag 63\ud
CHAPTER FOUR - Fractal analysis of granular materials pag.65\ud
4.1 Granular materials pag.65\ud
4.2 Stress in a silo pag.67\ud
4.3 Dantu’s experiment pag.69\ud
4.4 Experimental process pag.71\ud
4.5 Calculating fractal dimension pag.76\ud
4.6 Carbon paper’s impressions pag.78\ud
4.7 Analysis of s-independence for silo effect pag.142\ud
4.8 Photoelastic analysis pag.144\ud
4.9 Experimental data comparison pag.151\ud
4.10 Conclusions pag.154\ud
4.11 Applications to geological phenomena pag.155\ud
BIBLIOGRAPHY pag.15
Evaluation of diagnostic techniques for the detection of \ud Bovine Viral Diarrhoea Virus (BVDV) in infected and persistently infected cattle\ud
Get PDFBovine Viral Diarrhoea Virus (BVDV) is a significant pathogen associated with gastrointestinal, respiratory, and reproductive diseases of cattle worldwide. The ability of BVDV to cross the placenta during early pregnancy can result in the birth of persistently infected (PI) calves, which are capable of shedding large quantities of virus throughout their lives and are considered the primary reservoirs for BVDV. PI animals do not show antibody response, and diagnostic tests such as virus isolation,\ud
immunohistochemistry (IHC), Antigen-Capture ELISA (ACE), and RT-PCR are used in their detection. Control efforts based on the identification and elimination of PI animals have been successful in a number of countries around the world. In Italy, little research has been done concerning BVDV prevalence and at this time no compulsory/voluntary control program exists. In order to investigate the\ud
seroprevalence and to identify PI animals in Central Italy, a serological survey on 1,929 unvaccinated Holstein Friesian animals from 21 farms from the Marche, Umbria and Lazio regions was carried out. Sera samples were tested to detect BVDV antibodies using a commercial ELISA kit (Antibody BVDV IDEXX HerdCheck).\ud
In order to detect PI cattle, all young (2 years old) and seronegative animals were tested individually using a commercial ACE (Serum/ACE BVDV IDEXX HerdCheck) and a RT-PCR protocol using pooled sera samples. In order to compare two different epidemiological situations, a short survey of 2 months was carried out at the Veterinary Diagnostic Laboratory of the Colorado State University (Rocky Ford,\ud
Colorado, USA) where a BVD voluntary program based on the identification and elimination of PI animals has been implemented. The protocol was carried out testing surnatants of ear-notches individually by ACE (ACE BVDV IDEXX, USA) derived from positive pools previously tested by RT-PCR. A total number of 14,508 samples were received, conforming 360 pools with an average number of 40 samples each one.\ud
The results obtained in the serological survey of Central Italy demonstrated a total seroprevalence of 26.43%, meanwhile seroprevalences of 20.35%, 24.92% and 31.66% were observed in Umbria, Marche and Lazio regions respectively. These results showed the presence of BVDV infection with low prevalence. According to the age, 5.33% and 85.28% of animals younger and older than 2 years old respectively were positive. Only 10% (2/20) of farms showed recent infection of BVDV due to the presence of seropositive animals younger than 24 months old. All seronegative / young animals tested (No. 490) were negative with the Serum/ACE using both, the standard and the overnight incubation methods with the intent to improve the sensitivity of the test, as well as by pooled RT-PCR. As additional Serum/ACE kit evaluation, 10-fold serial dilutions of BVDV TMV-2 strain in BVDV negative serum were tested, and positive results were seen in a 10-3 dilution\ud
confirming its validity. Therefore, no PI animals were identified in our research.\ud
Several factors such as the low PI prevalence, intermittence of BVDV excretion, the presence of a low percentage of PI animals that do not show detectable viral titers, along with the changing levels of viremia in PI animals must be considered. Our results demonstrate the presence of BVDV infection even in the absence of PI\ud
animals, illustrating the possible important role of transiently infected (TI) animals in the long term circulation of BVDV. Probably risk of indirect or external avenues of transmission must be considered due to the presence of on-going infections. In addition, the current herd management practices and low cattle density in Central\ud
Italy may be contributors to the low presence of PI animals. On the basis of these results the BVDV spread in Central Italy does not appear critical. The application of\ud
other diagnostic techniques such as IHC, RT-PCR and ACE using buffy coat and/or ear notches samples to detect the presence of PI animals is strongly recommended.\ud
In other hand and following the protocol of the Colorado State University, 15 Hereford of 4 months old animals were detected as PI animals, representing a total prevalence of 0.1%. This prevalence has been described everywhere, ranging from 0.5 to 2%. The methodology used offered a low-cost and highly sensitive system to detect BVDV infected animals.\ud
Important differences as the number of animals sampled, the absence/ presence of a Control Program, the different samples used in each survey (serum vs. ear notch),\ud
differences in size, density and management, as well as the role of the presence of wild animals in the Colorado State are factors that must be considered between the different results observed in both surveys
New hybrid metal-organic materials polyfunctional containing N-donor ligands\ud
No full textDuring this work, we have synthesised and completely characterised four new ligands, twenty two novel coordination complexes and thirteen new hybrid Metal-\ud
Organic Framework (supramolecular and coordination polymers) silver(I), Zinc(II) and copper(II)-containing with fascinating and intriguing structural architectures. To\ud
achieve these results under mild conditions, we have chosen three secondary building units or building blocks (SBU): cationic unit by the trinuclear copper [Cu3(μ3-OH)(μ-\ud
C3H3N2)3]2+, neutral complexes such as [M2(O2CC10H6CO2)].nH2O and [M3(C9H3O6)2]n.nH2O (where M = Cu(II), Zn(II), C9H3O6 3- = trianion of benzene tricarboxylic acid), O2CC10H6CO2 2- = dianionic naphthalene dicarboxylate) and finally the simple building unit, Zn(HCOO)2.2H2O. Their reactivity towards rigid or flexible "spacers" or "linker" such as 4,4 '-bipyridine (bpy), 1,2-bis(4-pyridyl)ethane has been investigated.\ud
After the literature overview, we have focussed our attention to the polyfunctional reactivity of the copper trinuclear triangular [Cu3(μ3-OH)(μ-C3H3N2)3]2+ cores. The reaction in methanol of copper trinuclear core [Cu3(C3H3N2)3(OH)(C3H4N2)2R2] ( with R = HCOO- or H3CCOO-) with 4,4’-bipyridine, trans-(1,2-bis(pyridin-4-yl))ethene and bis(pyridin-4-yl))ethane had generated five novel hybrid Metal-Organic Framework (MOFs) well characterised by single-crystal Xray diffraction, elemental analysis, InfraRed spectroscopy and Thermogravimetry Analysis (TGA). Using the 4,4’-bipyridine, the two iso-strutural MOFs 2-1 and 2-6\ud
having intriguing structures, are isolated and crystallised in space group Ibam with a = 35.201(6) Å, b = 13.843(2) Å, c = 23.590(6) Å, α = β= γ= 90°, Z = 4 for MOFs 2-1\ud
and a = 36.098(3) Å, b = 12.766(10) Å, c = 24.031(2) Å, α = β= γ= 90°, Z = 4 for MOF 2-6 . Their structure determination reveals that they have 3D supramolecular network based on the stacking of the interpenetrating 2D honeycomb layers also resulting from the self-assembly of the 22-membered macrocycles or monomeric copper hexanuclear\ud
cores. Replacing the 4,4’-bipyridine by the flexible and more longer connector trans-(1,2-bis(pyridin-4-yl))ethene in the slightly modify conditions had gave rise to the two\ud
supramolecular isomers MOF 2-2 and 2-3 which crystallise respectively in triclinic space group P1 and monoclinic space group P21/n with a = 14.3105(5) Å, b = 15.3253(5) Å, c = 16.4073(6) Å, α = 99.7450(10)°, β = 108.313(2)°, γ = 98.198(2)°, Z = 1 (for MOF 2-2) and a = 24.9689(8) Å, b = 17.2737(5) Å, c = 29.6605(9) Å, α = γ = 90°, β = 92.623(2)°, Z = 8 (for MOF 2-3). The rhombic grid 2D-MOF 2-2 was\ud
constructed with the self-organisation of the 26-membered macrocyles forming the monomeric unit through the strong intermolecular hydrogen bonds. This open network which exhibits various types of cavities is completely different to the polymeric 1D zigzag chain of the isomer MOF 2-3. When the 4,4’-bipyridine was replaced by the bis(pyridin-4-yl))ethane, flexible spacer with the same coordination sites , another 3D open framework, MOF 2-4 (triclinic space group P1, a = 12.5276(6) Å, b = 13.6797(6) Å, c = 15.5767(7) Å, α= 92.059(2)°, β= 103.1640(10)°, γ = 92.201(2)°,\ud
Z = 2) was obtained. The polymeric crystal structure of this MOF or supramolecular coordination polymer was forming by the coordination of the branched bidimensional\ud
monomeric structure through one bis(pyridin-4-yl))ethane and the intermolecular hydrogen bonds. In these five MOF structures, there are π-π interactions. These results\ud
indicate that the nature of the co-ligand or connector plays the critical role in the construction of these novel hybrid coordination polymers or Metal-Organic Frameworks.\ud
The second part of this report, described the synthesis of the new ligands and their reactivity towards metal ions of Group 11 and 12. In fact, these N-donors chelating and bridging ligands named (bis(indazol-1-yl)methane , Monoclinic with space group C2, a = 23.6048(7) Å, b = 4.10040(10) Å, c = 13.9516(4) Å, α = 90°, β = 117.8300(10)° , γ = 90° , Z = 4; bis(indazol-2-yl)methane, Monoclinic with space group P21, a = 4.5053(3) Å, b = 11.5398(8) Å, c = 11.9930(8) Å, α = 90°, β= 99.550(2)°, γ = 90°, Z = 2; 1-((indazol-2-yl)methyl)-indazole, Monoclinic with space group P21/c , a = 10.0876(5) Å, b = 8.1834(4) Å, c = 14.7602(7) Å, α = 90°, β = 98.168(2)°, γ = 90°, Z = 4), and bis(4,5,6,7-tetrahydroindazol-1-yl)methane, orthorhombic with a space group Pccn, a = 19.1237(15) Å, b = 8.4206(7) Å, c = 8.4529(7) Å, α = 90°, β = 90°, γ = 90°, Z = 4) have been synthesised using two methods: the reported well-known “Phase Transfer Catalyst (PTC)” and a new one here reported. The complementary confirmation of their structural characterisation was obtained from DFT calculations. By using these ligands, we have prepared and structurally characterised nine derivatives from their reaction with simple salts of d10 metals (silver(I), zinc(II), mercury(II) and Cadmium(II)). With the silver(I) salt, complex salts exhibiting the common tetracoordination on Ag(I), (3-10) [Ag(Bindm)2](NO3): monoclinic, space group P21/c, a = 11.3092(6) Å, b = 12.2646(6) Å, c = 20.1430(10) Å, α= 90°, β= 98.080(2)°, γ = 90°, Z = 4 and (3-20) [Ag(Bitim)2](NO3): triclinic, space group P1, a = 9.1219(9) Å, b = 14.2797(13) Å, c = 24.510(3) Å, α = 79.043(4)°, β= 79.298(3)°, γ = 77.068(3)°, Z = 4 containing two moieties Bindm or Bitim are reported. Also reported is a neutral\ud
derivative containing two ligands Bindm, showing the interesting six-coordination on Cd(II) (3-17) [CdCl2(Bindm)2]: triclinic, space group P1, a = 7.9331(12) Å, b=\ud
7.9480(12) Å, c = 12.5068(18) Å, α = 83.519(7)°, β = 72.527(7)°, γ = 67.587(6)° and Z= 1. With the mercury and zinc salts, it was observed that only one ligand molecule is\ud
chelating the metal centre which is then occupies the center of distorted tetrahedral. It is the case of the following five reported derivatives (3-21) [ZnCl2(Bitim)] (triclinic space group P1, a = 7.3686(18) Å, b = 9.388(2) Å, c = 12.975(3) Å, α = 80.438(6)°, β= 74.252(6)°, γ = 86.260(7)°, Z = 2); (3-6) [ZnBr2(Bindm)] (Orthorhombic, space group Pnma, a = 13.2080(11) Å, b = 14.2483(12) Å, c = 8.5448(7) Å, α= 90°, β= 90°, γ = 90°, Z = 4); (3-5) [ZnCl2(Bindm)](monoclinic, space group P21/m, a = 7.2900(11) Å, b\ud
= 14.101(2) Å, c = 8.2929(13) Å, α= 90°, β= 112.802(4)°, γ = 90°, Z = 2); (3-11) [Hg(SCN)2(Bindm)](monoclinic, space group P21/n, a = 12.3387(5) Å, b = 8.1098(3) Å, c = 18.1621(7) Å, α = 90°, β = 96.9590(10)°, γ = 90°, Z = 4) and (3-13)\ud
[HgCl2(Bindm)](triclinic, space group P1, a = 11.7136(5) Å, b = 12.5791(5) Å, c = 14.1761(6) Å, α = 72.102(2)°, β= 71.534(2)°, γ = 79.366(2)°, Z = 2).\ud
Analogously to the work carried out in chapter 2, variety of diamine linkers (en, tn, pn, bipy, bipyetha, bipyethe) and/or monodentate N-donor ligand (pyrazole, imidazole and some of their derivatives) have been reacted at room temperature with a series of metal acceptors Zn(OOCH)2.2H2O, Zn(O2C-naph-CO2)2.3H2O or Zn(NDC)2.3H2O, Zn3(1,3,5-BTC)2.8H2O, CuNDC. 3H2O and Cu3(1,2,3-BTC)2.3H2O (where 1,3,5-BTC3- = 1,3,5-benzenetricarboxylate trianion, 1,2,3-BTC3- = 1,2,3-benzenetricarboxylate trianion and NDC2- = naphthalene dicarboxylate dianion) to obtain twenty nine new derivatives characterised by the elemental analysis,\ud
spectroscopic and X-ray diffraction techniques for someone.\ud
The reaction with zinc carboxylates have yielded the isolation of seventeen derivates among which five are completely structurally characterised: the complex derivative [Zn(imH)6](OOCH)2 (4-1), the coordination polymers 1D-MOFs (4-4){[Zn2(µ-OOCH)(OOCH)3(bipy)2(H2O)2].H2O}. and (4-7){[Zn2(OOCH)4(µ-bipyetha)].4H2O}. with a zig-zag array crystal structure; and finally, two inorganic supramolecular isomers, 1D-MOF [Zn2(OOCH)4(µ-bipyethe)]. (4-5)and 3D-MOF [Zn2(µ-OOCH)4(µ-bipyethe)(OH2)2]. (4-6). Their crystallographic parameters are the following: (4-1): Space group P21/a, a: 8.355 Å, b: 16.9590Å , c: 8.9400 Å, α: 90°, β: 91.68°, γ : 90 ° ; (4-4): Orthorhombic with space group Pbca, a = 6.7651(8) Å, b = 17.4876(19) Å, c = 23.180(3) Å, α = β = γ = 90°, Z = 8; (4-5): Monoclinic, P2/n, a = 8.8105(3) Å, b = 4.8235(2) Å, c = 16.4502(7) Å , α= 90°, β=\ud
102.9150(10)°, γ = 90° Z= 2; (4-6): Monoclinic, C2/c, a = 37.8876(14) Å, b = 7.6025(3) Å, c = 25.4422(9) Å, α= 90°, β= 90.489(2)°, γ = 90° , Z = 8 and (4-7): Monoclinic, C2/c , a = 18.0718(9) Å, b = 4.6178(3) Å, c = 17.3126(9) Å, α= 90°, β= 96.329(2)°, γ = 90°, Z = 4.\ud
We have equally isolated variety of copper(II) derivatives from which three were structurally characterised: the complex salt derivative [Cu(tn)2(H2O)2](NDC).3H2O (4-\ud
26) which crystallises in system triclinic and Space group P1, a = 7.3274(2) Å, b = 9.9798(3) Å, c = 11.5687(3) Å, α= 100.6210(10)°, β = 95.1010(10)°, γ= 97.6160(10)°, Z = 1; and two Metal-Organic Frameworks 1D {[Cu(NDC)(tn)(H2O)(µ-H2O)].1/2H2O}8 (4-25) crystallising in Monoclinic system and\ud
space group P21/c, a = 11.4293(4) Å, b = 10.4074(4) Å, c = 12.4403(5) Å, α= 90°, β= 117.2450(10)°, γ = 90°, Z = 2 and 2D {[Cu3(1,2,3-BTC)2(en)3(µ-H2O)(H2O)3].3H2O}.(4-29) with a space group P-1, a =12.157(2) Å, b=12.874(3) Å, c=14.054(3) Å, α= 75.08(3)°, β= 74.45(3)°, γ = 68.03(3)°.\ud
Similarly to the previous derivatives reported in chapter 2, the connector trans-(1,2-bis(pyridin-4-yl))ethene (bipyethe) reacted with zinc formate (simple unit)\ud
concomitantly gave rise to two supramolecular isomers. The MOFs (base either on zinc carboxylate or copper carboxylate derivatives) exhibit in the overall crystal structures\ud
various types of open cavities or channels with someone occupy with solvent or water molecules.\ud
The thermal analysis show that these MOFs could be considered as perspective materials for gas storage until to 180°C.\ud
During the last part of this work, devoted to the synthesis of new coordination compounds based on phosphorous donor (mono- or di-) and N-donor ligands, we have reported the preparation of twenty one new compounds where eleven are structurally and completely characterised.\ud
In more details, seven silver adducts (either monomeric or polymeric species) were structurally characterised from the interaction of silver(I)diethyldithiocarbamate (Ag(dtc)) with phosphorous donor (mono- or di-) ligands: monomeric species (5-7)[Ag(dtc)(PMePh2)2] (monoclinic with P21/c, a =10.2830(8)Å , b = 30.099(2)Å , c = 10.8760(8)Å, β =115.990(2)°, Z = 4), (5-13) [Ag(dtc)(dppet)] (monoclinic with\ud
P21/n, a = 9.9615(9)Å , b =17.923(2)Å , c =16.932(2)Å, β = 95.235(2)°, Z = 4); dimeric species (5-1) [Ag(dtc)(PPh3)]2 ( triclinic, space group P1, a=10.410(1)Å, b = 10.641(1)Å, c = 10.867(1)Å, α = 92.523(3)°, β = 93.573(3)°, γ = 109.409(3)°, Z = 1 dimer ), (5-3) [Ag(dtc)(P-m-tolyl3)] (triclinic with space group P1, a = 10.373(1) Å, b = 11.441(1) Å, c = 12.275(2) Å, α = 71.407(2)° , β = 68.949(2)°, γ = 84.512(2)°, Z = 1 dimer ), (5-8) [Ag(dtc)(dppm)]2 (monoclinic with space group C21/c , a = 24.022(6)Å, b = 10.234(2)Å , c = 27.114(4)Å, β = 118.37(2)°, Z = 4 dimers), and polymeric\ud
species or 1D polymer (5-6) [Ag(dtc)(PMePh2)]. (monoclinic with P21/n, a = 13.041(1)Å , b = 7.4238(6)Å , c = 19.892(2)Å, β = 93.237(2)°, Z = 4), (5-10) [Ag(dtc)(dppp)]. (monoclinic with P21/c, a = 14.880(2)Å , b = 12.035(2)Å , c = 18.025(2)Å, β = 101.09(1)°, Z = 4). Apart from derivative (5-1) where Silver (I) is pentacoordinated (P2AgS3), all the derivatives exhibit the tetracoordination (P2AgS2 or\ud
PAgS3) on silver centre.\ud
By reacting variety simple salts of Cu(I) with the 2,9-dimethyl-1,10- phenanthroline (dmp), eight new copper (I) derivatives have isolated among which, four were structurally characterized: (5-14) [Cu(dmp)(MeCN)]NO3 (monoclinic with P21/c, a = 10.8080(4)Å , b = 19.5740(8)Å , c = 7.8400(3)Å, β = 111.206(1)°), (5-15) [Cu(dmp)2]NO3 (monoclinic with C2/c, a = 17.648(4)Å , b =11.698(2)Å , c =\ud
12.466(3)Å, β = 113.61(3)°), (5-16) [Cu(dmp)2]ClO4 ( ), (5-17) [Cu(dmp)2]Cl (triclinic with space group P1, a = 12.799(3)Å , b = 13.598(3)Å , c = 18.688(4)Å, α = 70.011(3)° , β = 80.498(3)°, γ = 64.332(3)°).\u
Effect of different environmental contaminants on trout\ud erythrocyte components\ud
No full text\ud
Gli inquinanti ambientali come metalli pesanti (Pb, Cd, Hg), composti organometallici, contaminanti radioattivi giocano un ruolo importante nell’insorgenza e sviluppo di malattie.\ud
Un aumento dei livelli di piombo nell’organismo umano conduce a malformazioni cerebrali, disordini dello sviluppo embrionale, atrofia della membrana mucosa del tratto gastrointestinale ed indebolimento strutturale e funzionale delle membrane eritrocitarie (Lockitch et al, 1993). Il cadmio è coinvolto con l’immunità cellulare compromettendo l’attività dei leucociti polimorfonucleati e inibendo il processo di differenziazione dei cloni e l’attivazione dei linfociti maturi (Tang et al. 1990). L’intossicazione cronica da mercurio porta ad uno sviluppo del gozzo prominente, disturbi della funzione endocrina della tiroide, alterazioni delle proteine con gruppi SH, ossidazione, inibizione dell’attività di un certo numero di enzimi (Clarkson et al., 2002). Tra i composti organometallici, gli organostagni sono contaminanti ubiquitari negli ecosistemi acquatici (Fent 1996); essi sono pericolosi per gli organismi acquatici a causa della loro attività neurotossica, epatotossica, immunosoppressiva. Lo stagno tributile (TBT), uno dei composti più tossici presente nelle acque marine e dolci, ha portato a impatti deleteri nei porti ed in altri siti contaminati. Come conseguenza, l’uso di TBT nelle vernici antialga per le imbarcazioni private è stato limitato o\ud
vietato in diversi paesi, ma è ancora in uso nelle grosse navi. Conseguentemente alle limitazioni nella vendita, i livelli di TBT sono sostanzialmente diminuiti, ma nelle aree contaminate rimangono tracce nel range dei ng/l. Residui rilevanti permangono ancora nei molluschi di acqua dolce e nei mammiferi marini.\ud
Le contaminazioni radioattive hanno un forte impatto nella salute di tutti gli organismi viventi (Kozarezova et al. 1996). Quando il nucleo dell’uranio (U-235) si divide in un reattore nucleare, si generano diversi prodotti di fissione. I più rilevanti in termini di dannosità sono lo iodio 131, il cesio 137, lo stronzio 90 ed il plutonio 239. Questi elementi sono aerodispersi e possono essere\ud
inalati, depositati nella terra grazie alle piogge ed alle acque o entrare nella catena alimentare tramite le piante. Iodio 131, cesio 137, stronzio 90 e plutonio 239 sono elementi radioattivi instabili che decadono formando nuovi elementi e rilasciando energia sotto forma di radiazione. Quando le cellule sono esposte a queste radiazioni vengono prodotti radicali liberi e questi possono compromettere le funzioni cellulari. Il danno può interessare il DNA e causare cancro ed altre anomalie genetiche. Considerato il grosso impatto nella salute di tutti gli organismi viventi, la ricerca scientifica è dedita a studiare gli effetti di molteplici contaminati sui sistemi biologici.\ud
Il nostro interesse in questo settore ha riguardato i composti organo-stagno di nuova sintesi e due metalli, Rame e Cadmio. Gli effetti di questi contaminanti ambientali sono stati valutati utilizzando come modello cellulare il globulo rosso della trota “Oncorhynchus mykiss”\ud
\ud
The effects of new triorganotin (IV) derivatives containing the anionic ligand Sodiobis(1-metil-2-imidazoliltio)acetato,Na[(S-tim)2CHCOO] was evaluated on trout\ud
erythrocyte components. Our results referred to plasma membrane perturbation, hemoglobin and nuclear DNA show that the toxicity of the organotin (IV) complexes was present in all cellular compartments and it depends on the nature and lipophilicity of the substituents on the metal center. Analogues studies were performed to evaluate the effect of two metals that have a different chemistry, copper and cadmium.\ud
The chemistry of copper makes it an ideal partecipant in redox reactions, as it easily cycles between the cuprous and cupric state. Although these differences in our\ud
experimental conditions the results obtained indicate a similar effect : both are capable to perturb plasma membrane while they do not alter the nuclear DNA status
Immunohistochemical expression of hormonal receptors in normal and neoplastic mammary tissue in the dog
No full textThe mammary carcinoma is the most frequent tumor in the women as well as in the bitches. In human medicine, the evaluation of immunohistochemical expression of estrogen receptors (ER) α and β, progesterone receptor (PR) and androgen receptor (AR) is very useful to predict prognosis and response to endocrine therapy. However, in veterinary medicine, there is little knowledge of the role of these elements in canine mammary tumors. Especially, the information concerning the expression and significance of AR are very scant. Moreover, among the canine mammary tumors there are often complex/mixed neoplasm, characterized by neoplastic transformation of myoepithelial cells. These cells are involved in the mammary cancer progression, but to date there are not specific studies about their receptorial assessment. The aim of this work was to verify, in canine mammary tumors, the existence of correlations between biological behaviour and immunohistochemical expression of ERα, ERβ, PR and AR.\ud
A group of thirty bitches with mammary neoplasm was included in the study. Clinical and reproductive histories were obtained from their owners. The animals were subjected to physical examination and thoracic X-ray. Clinical staging of tumors was carried out according to criteria of WHO. Partial or total mastectomy was performed and the whole tissue, fixed in buffered neutral formalin, was sent to Laboratory of Animal Pathology - University of Camerino (Italy). The animals were followed during a year after the surgery. The plan of follow up included clinical examination and thoracic X-ray.\ud
Thirty-two tumors were collected and examined. Histological classification and grading were carried out according to criteria of WHO. The immunohistochemical expression of ERα, ERβ, PR and AR was assessed for each sample. Statistical analysis was performed by Student’s t-test and Spearman’s correlation.\ud
We found specific nuclear reaction against all the receptors in normal and neoplastic epithelial and myoepithelial cells. Only the immunodetection of ERα was higher in young bitches (p<0,05) whereas the expression of all the other receptors was not correlated with the age. There were not correlations between receptorial assessment and reproductive variables. The expression of every receptor was higher in normal tissue and benign tumors than in malignant neoplasm. Among malignancies, the lowest levels of every receptors were detected in high grade carcinomas (p<0,01). Levels of ERα and PR were inversely correlated with the presence of regional (p<0,01) and/or distant (p<0,05) metastasis. A lower expression of ERβ was found in carcinomas with nodal positive status (p<0,05) whereas a high level of AR seemed weakly correlated with development of distant metastasis (p>0,05). A high expression of ERα and/or PR appeared as a good prognostic factors for the DFS (p<0,01). ERβ also displayed a positive prognostic significance (p<0,05). On the other hand, the levels of AR were inversely correlated only with grading but we showed a slight positive correlation with metastatic power of carcinoma (p>0,05). In human breast carcinoma, AR seems to be involved in metastatic development by up-regulation of metalloprotease of matrix (MMP). Therefore, evaluating the correlation among presence of AR, expression of MMP and appearance of distant metastasis also in canine mammary tumors could be very interesting. On the contrary we not found important correlations between the receptorial status of myoepithelial cells and the biological behaviour of tested cases.\u
Design, synthesis and pharmacological evaluation of new potential tools for the treatment of central nervous system diseases involving dopamine receptors
No full textSchizophrenia is a CNS pathology first described over one century ago. Since that time many discoveries have been done, but still several pathophysiology details are unclear, however, the dopamine hypothesis, emerged forty years ago, still remain one of the main possibility. Since the discovery of chlorpromazine the antipsychotic drugs have been the treatment of choice for schizophrenia and their activity appears to be accounted to the high affinity and antagonistic activity at D2 receptors. However, they are responsible of severe side effects mainly related to the dopamine receptor antagonistic activity itself. A newer approach seems to be represented by the use of D2-like receptor partial agonists. Drugs with such a mechanism of action could act as antagonists where the dopaminergic activity is oversized, and, at the same time, as agonists where the dopaminergic activity is reduced. Some molecules showing dopaminergic D2 partial agonist activity are based on the template moiety 2-(3-hydroxyphenoxy)ethylamine 1. Based on the beneficial role on D2-like receptor affinity played by the reported conformational restrictions given by benzodioxane and benzodihydropyran rings, we have designed and synthesized (chapter 2) a series of compounds embedding the template moiety in a partially (tetrahydroisoquinoline) or fully rigid (tetrahydrochromenoisoquinoline) molecules. The receptor binding affinities toward DA receptor subtypes of the new compounds were evaluated. The obtained results show that in the tetrahydroisoquinoline series only compound 6b displays low affinities for D2 (3.93 mM) and D3 (2.10 mM) receptor subtypes. Compounds 7a,b, belonging to the tetrahydrochromenoisoquinoline series, show affinity values comparable to those of 6b, but a selectivity toward DA D3 receptor subtype may be underlined. Although lower affinity values, the results are in agreement with the binding profile of the lead compound, which shows quite good selectivity for the D2-like receptor family, especially toward the D3 receptor subtype. Compounds 6b and 7a,b embed the structure of the lead in a partially or fully rigid conformation, respectively. Such a feature, reduces or annuls, respectively, its conformational freedom, locking the conformation in a non-effective one. The behavioral activity and the effects on brain neurochemistry of the synthesized compounds 6b and 7a,b were also evaluated in vivo in rats. No statistically significant changes in behavioral activity and no statistically significant changes in rat brain neurochemistry were observed after s. c. administration of the compounds 6b and 7a,b in the dose range 3.7-100 µmol/kg. The pharmacological data led us to conclude that even if the template structure is endowed with dopaminergic activity, a high level of conformational freedom seems to be crucial for a high affinity binding to the dopamine receptors.\ud
Several studies demonstrated the versatility of the imidazoline ring. In fact, depending on the particular kind of substituent inserted in position 2 of imidazoline nucleus, it was possible to modulate the ligand profile, both with regard to different systems (a2-Adrenergic Receptors, Imidazoline Binding Sites, Nicotinic and Muscarinic Receptors, MAO-A inhibitors) and inside the same system, with resultant enhanced subtype selectivity. Imidazoline compounds have not been yet explored as DA receptor ligands, but the well known prototype of I2 receptor ligands 2-(benzofuran-2-yl)-4,5-dihydro-1H-imidazole (2-BFI) behaved also as DA indirect agonist and displayed a 47 mM binding to the DA D2 receptors. Therefore, with the aim to improve the DA D2-like receptor binding affinity, novel molecules based on the 2-BFI scaffold were designed and synthesized (chapter 3). The 5 and/or 6 substituents R1-R3 were chosen among those reported to be beneficial for the binding of DA D2-like receptor agonists. Competitive binding of the new compounds at DA D2-like receptors has been evaluated on porcine striatal membranes. The affinity at I2-IBS and a2-ARs has also been evaluated on rat brain membranes. All values are expressed as Ki (mM) values. The most interesting compounds have also been tested for D2-like potency and intrinsic activity. Interestingly, it has observed that the 2-BFI is able to induce a partial activation of D2-like receptor (EC50 = 37.7 mM; i.a.= 0.57). The modest and conservative modifications performed on the basic structure of the lead modulated its biological profile. The introduction of one hydroxyl group in position 6 of the aromatic ring (compound 3f ) slightly enhances, the D2-like profile of the lead. Moreover, 3f behaves as partial agonist (EC50=5.7 mM, i.a.=0.48) displays a potency comparable to that of DA. Moreover, it maintains significant I2-IBS affinity (Ki = 0.076 mM). On the contrary, the isomer 5-hydroxy substituted 3a, still endowed with good I2-IBS, was unable to bind at the D2-like receptors. It appears that only the maintenance of a meta relationship between the OH group with respect to the benzofuranic oxygen atom, proved to be endowed with D2 affinity. The negative influence of the 5-hydroxy substitution is also observed in the catechol derivative 3i that showed strongly reduced I2 character compared to the lead, and was not able to interact with D2 like receptors. Interestingly, the N-substitution seems to impart a more decisive modulation of the biological profile to the lead. In fact, such a modification caused general decrease of the I2-affinity, with, in some cases, accompanying significant D2-like intrinsic activity enhancement. In particular, the N-benzyl derivatives behaved as a nearly D2 full agonists (3e: i.a.=0.85; 3h: i.a. = 0.82), with affinity (3e: Ki = 5.00 mM; 3h: Ki = 5.66 mM), and potency (3e: 6.3 mM; 3h: 5.8 mM) comparable to those of DA (Ki = 3.9 mM; EC50 = 4.8 mM). By our results it can be argued that the degree of receptor activation, is favored by the N-substitution, and might be affected by peculiar features of the pendant group (i.e. steric hindrance) and, sometimes, by the structural characteristics of the parent compound. \ud
Parkinson’s disease (PD) is a progressive, neurodegenerative disorder which involves the loss of dopaminergic neurons of the substantia nigra pars compacta. Current therapy is essentially symptomatic, and L-Dopa (LD), the direct precursor of dopamine (DA), is the treatment of choice in more advanced stages of the disease. Substitution therapy with LD is, however, associated with a number of acute problems mainly correlated to the poor bioavailability strictly connected with the drug’s physical-chemical properties, such as low water and lipid solubility, and the high susceptibility to chemical and enzymatic degradation. With the aim to ameliorate the bioavailability of LD we designed and synthesized some its imidazolinones prodrugs (chapter 4). The choice to embed the aminoacidic group of L-DOPA into the imidazolinone structure derives from reported studies concerning pharmacologically active peptides. Thus, conjugation of LD with glycine gives a dipeptide that can be converted in an imidazolinone protection system that, compared to LD, is more lipophilic and less sensitive to metabolic degradation, meanwhile able to release the drug after spontaneous or enzyme catalyzed chemical hydrolysis. The physical-chemical parameters water solubility and octanol/water partition coefficient were determined on the new compounds (see chapter 4). The chemical stability of the new prodrugs was assayed in vitro in aqueous buffer solutions of pH 1.3 (non enzymatic simulated gastric fluid) and pH 7.4 and the products of the reaction were characterized. Their enzymatic stability was also studied at 37 °C in 80% rat and in 80% human plasma. Taken together, the results indicate that the inclusion of the aminoacidic moiety of LD in a imidazoline-4-one ring give prodrugs that might be able to across unchanged the acidic environment of the stomach, stable enough to be absorbed from the intestine, and then release LD in human plasma after enzymatic hydrolysis. However, further modifications of the prodrug molecules to increase their lipophilicity seems to be necessary in order to boost the possibility of a good intestinal adsorption. Further biochemical and pharmacological studies have been developed in order to test the capability of prodrugs to increase the basal level of striatal DA and influence the brain neurochemistry strictly connected with the dopaminergic activity. \ud
Concerning the basal level of striatal dopamine compound 6a showed a long lasting effect. The obtained profile may indicate a slow release of LD to the brain that might represent a positive feature for the reduction of the frequency of drug administration. The measurement of the basal level of the metabolite 3,4-dihydrophenyl acetic acid (DOPAC) confirms the previous statement being the incremental profile of the basal level of DOPAC comparable to that of DA. \ud
It has been reported that chronic oxidative stress induces progressive irreversible damage affecting the normal physiological functions of the central nervous system, and seems to play a crucial role in several CNS diseases, including Parkinson’s disease. Phenolic compounds are known to be active antioxidants quenching oxygen-derived free radicals by donating hydrogen atom or an electron to the free radical. The DPPH (diphenyl-P-picrylhydrazyl) radical assay measures the most common natural antioxidants, especially phenols. Thus the radical-scavenging activity against DPPH was evaluated on compounds 6a,b and (S)-15a and on vitamin E, caffeic acid and LD as reference compounds. From the obtained results it can be observed that the compound 6b display an high antioxidant activity comparable to that of the reference compounds even at low concentration. The di-acetyl derivative (S)-15a proved to be the less active in the series probably because it lacks the catecholic or phenolic function. Finally, we have synthesized a new LD prodrug based on an imidazolinone nucleus. Our catecholic compounds might be able to across unchanged the acidic environment of the stomach, are stable enough to be absorbed from the intestine, and they release LD in human plasma after enzymatic hydrolysis. However, work are in progress to evaluate whether an improvement of their lipophilicity might be useful for ameliorate their possibility of adsorption after oral administration and their distribution to the central nervous system.\u
Experimental Quantum Key Distribution at Telecom Wavelength\ud
No full textCryptography is the art of transmitting readable information to authorized users and unintelligible information to unauthorized users. Cryptanalysis\ud
is the art by unauthorized users of reading information considered unreadable.\ud
The struggle between cryptographers and cryptanalysts has a long and remarkable history, and is currently at the basis of every confidential communication.\ud
The above-mentioned struggle has been mostly played in the field of mathematics.\ud
However it was recently discovered that the ultimate horizon of security is not a matter of mathematics but rather of physics: Quantum Cryptography (QC) shifts the focus of security from complex algorithms to fundamental theorems of quantum mechanics, which area exploited to reach\ud
the highest possible level of security.\ud
Two decades of experience has shown that QC is a matter of photonics, for the only advances in QC implementations have appeared in this field. No other physical quantum system but photon is so easily generated, transmitted, controlled and detected. it was the simplicity of these operation to promote in few years the photon-based QC from the theoretical speculation in to the practical reality.\ud
My PhD work deals with the experimental realization of a QC setup. An apparatus for QC working at Telecom wavelength is developed using fiber-based integrated optical elements. Two different QC protocols are implemented and their performances are compared.\ud
This thesis is arranged in the following way. The first introductory chapter gives a brief idea on the history of classical cryptography (CC) together with a few examples of CC. Later on the chapter Quantum Key Distribution (QKD) is introduced.\ud
The necessary theoretical aspects of the subject are given in the second chapter.\ud
Here we explain how a quantum system carries information and how the laws of quantum mechanics give security to the communication. The QBER, an important quantity of QC, is introduced in terms of fidelity. Following to this, information is quantified in terms of entropy. Error correction and privacy amplification, which are necessary classical procedures for distilling a secure key, are detailed along with the final secure key distillation process.\ud
The third chapter is dedicated to the theoretical aspects of the two protocols implemented in our apparatus. Two specific eavesdropping strategies and a direct comparison between the two implemented protocols are given.\ud
The experimental details of the apparatus are explained in the fourth chapter, where different layers of the setup are described. The chapter also deals with the system alignment techniques used to perform faithful key distribution.\ud
The performances of the apparatus and comparative study of the protocols are given in the chapter five. We conclude with a summary of the contents and a few final remarks on the QC subject.\u