197,480 research outputs found
La Collezione numismatica
No full textDescrizione delle caratteristiche, dei criteri di raccolta e del valore documentario per la conoscenza della storia romana delle Collezione Numismatica raccolta dal Fusignanese Carlo Piancastelli e conservata nei Musei di Forlì
Aeternitas e il crescente lunare in età repubblicana, ovvero la riabilitazione di Tarpeia,
No full textHomo/Heteropentanuclear Porphyrazine MgII, ZnII, and PdIIMacrocycles with Externally Pending PdCl2and Pd(CBT)2Units: Synthesis, Physicochemical Characterization, and Photoactivity Studies
No full textRecent work has been developed on two new classes of neutral porphyrazine complexes of formulas [(PdCl2)4Py8PzM]·xH2O (Py8Pz = octakis(2-pyridyl)porphyrazinato anion; M = MgII(H2O), ZnII, PdII) and [{Pd(CBT)2}4Py8PzM]·xH2O (M = MgII(H2O), ZnII CBT = m-carborane-1-thiolate anion). Characterization of all the species has been conducted by IR and UV-visible spectral measurements in a systematic comparison with the corresponding already known mononuclear species [Py8PzM] (M = MgII(H2O), ZnII) and the mono-PdII analogue isolated and presented here for the first time. Comparison includes also the two parent classes of pentanuclear tetrapyrazinoporphyrazines having the more extended π-electron delocalized macrocyclic core Py8TPyzPz. The reported new classes of pentanuclear complexes behave as active photosensitizers in photodynamic therapy (PDT), and due to the high boron content of the CBT derivatives, perspectives for them are open of application in the field of bimodal PDT/BNCT (boron neutron capture therapy) anticancer treatments
BENIGN JOINT HYPERMOBILITY SYNDROME: PSYCHOLOGICAL FEATURES AND PSYCHOPATHOLOGICAL SYMPTOMS IN A SAMPLE PAIN-FREE AT EVALUATION
No full text30 subjects with BJHS (Hypermobile) (M age = 32.3 yr., SD = 10.4) and two control groups, 25 healthy subjects (Healthy) (M age = 33.9 yr., SD = 9.3) and 30 fibromyalgic patients (Fibromyalgic) (M age = 32.2 yr., SD=9.4), were given the Symptom Checklist-90-R, the Illness Behavior Questionnaire, the Female Functional Symptoms Frequency (FFF) and the Male Functional Symptoms Frequency (MFF), derived from the DSM-III-R, evaluating functional somatic disturbances and their intensity, and the Symptom Questionnaire. The mean scores for the Hypermobile group showed significant psychological distress and increased frequency and intensity of somatic symptoms. Scores on Anxiety and Somatic Symptoms, General Hypochondriasis, Disease Conviction, Affective Disturbance, Denial, and Irritability were significantly higher in the Hypermobile than in the Healthy group. Elevated scores were found for the Fibromyalgic group on the Illness Behavior Questionnaire subscales for Psychological vs Somatic Focus, Disease Affirmation, and Discriminating Factors when compared with the Hypermobile group. Considerable emotional symptoms were detected which should not be underestimated by physicians when establishing an integrated biopsychosocial therapy
Physical basis of self-assembly. Part 2. A theoretical and experimental study of the self-assembly of a zinc meso-pyridyl porphyrin
No full textA previously reported theoretical treatment for self-assembly macrocyclisations occurring under thermodynamic control has been tested experimentally. The fundamental quantities on which the treatment is based are the effective molarity (EM) of the self-assembling cyclic n-mer and the equilibrium constant for the intermolecular model reaction between monofunctional reactants (Kinter). Provided that estimates of EM and Kinter are available, this treatment can be used to predict not only whether the self-assembly process is more or less favoured, but also the distribution of all the species present in solution. Since Kinter values are approximately known from the literature, we have proposed a method, based on molecular modelling techniques, to estimate the EM. The method has been applied to the self-assembly of Zn(PyP3P), where PyP3P is 5-(4-pyridyl)-10,15,20-triphenylporphyrinato dianion. An EM greater than 0.1 mol L-1 has been estimated for its cyclotetramerisation by PM3 calculations, suggesting that self-assembly should be favoured in solvents like toluene and chloroform. Self-assembly of Zn(PyP3P) has been studied in these solvents by UV/visible spectroscopy. The data are consistent with the formation of the cyclotetramer, and at variance with the model of linear polymerisation. The experimental values of the EM were little affected by the nature of the solvent (EM values were 20 mol L-1 in toluene and 15 mol L-1 in chloroform), indicating that the solvent affects the process of self-assembly mainly through the value of Kinter
Assessment of cooperativity in self-assembly
No full textA method has been proposed to assess cooperativity in self-assembly processes. The method is based on a clear distinction between intermolecular and intramolecular processes which are compared with the corresponding reference reactions. It has been applied to two classical cases, namely the self-assembly of helicates and of porphyrin ladders, by using data previously published by the groups of Lehn and Anderson, respectively. Contrarily to the conclusions of the authors, pointing out self-assembly processes driven by positive cooperativity, the method here presented indicates in both cases the absence of cooperative effects. The methods previously used to assess cooperativity, in particular Scatchard plot and/or Hill plot, are criticized as being inappropriate for self-assembly, because they are pertinent to a specific case only, namely the intermolecular binding of a monovalent ligand L to a multivalent receptor M, a case very different from self-assembly which involves both inter- and intramolecular interactions. The present method underscores the fact that positive cooperativity in artificial self-assembling systems is probably much more rare than it was previously thought
Boron containing mono- and bis-carboranethiolate derivatives of respective formula [(bipy)MCl(CBT)] and [(bipy)M(CBT)2] (M = PdII, PtII)
No full textSynthetic procedures are reported of the new “low molecular weight” mononuclear Pd II and Pt II derivatives of formula [(bipy)MCl(CBT)]⋅0.5CH 3 CN (M = Pd II , Pt II ) and [(bipy)Pt(CBT) 2 ] (CBT = m-carboranethiolate anion) evaluated of interest as potential anticancer agents in boron neutron capture therapy (BNCT). The structure of all
three species has been elucidated by single-crystal X-ray work and further examined by IR and UV–visible spectral behavior. The detailed presentation of the spectral response for all of them in solution of low-donor non-aqueous solvents (CH 3 CN, DMF, DMSO) evidences the presence of a broad absorption in the region 400–500 nm,
already previously observed for the species cis-[(bipy)Pd(CBT) 2 ], this absorption interpreted as due to the presence of one or two metal-CBT environments in the related cis-structurally arranged mono- and bis-CBT
derivatives
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