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This research aims at validating the SIMULATE-3K code and complementing the results with the quantification of nuclear data uncertainties against the Special Power Excursion Reactor Test III (SPERT-III) experiments. To that aim, the SHARK-X methodology, under development at PSI, for the propagation of nuclear data uncertainties in CASMO5 2-D lattice calculations to 3-D core transient simulations is applied for the analysis of a SPERT-III super-prompt critical test conducted at cold startup conditions. Concerning transient results, both total power and reactivity show a good agreement with the measurements at the initial phase of power excursion, while a slight discrepancy is obtained at the final phase of the transient. The estimated uncertainties regarding both steady-state parameters such as k-eff and static reactivity worth, as well as dynamical quantities such as power pulse width and enthalpies are presented. Results show non-negligible sensitivity upon the employed nuclear data library. The uncertainty quantification results show relatively small biases for k-eff and reactivity. The uncertainty in peak power is around 3%, while it is negligible for the time to peak power and the pulse width. The time evolution of the standard deviation and skewness of the total power showed special shapes with relatively high maximum values. In addition, the uncertainty due to nuclear data in the two important safety parameters, i.e. maximum nodal fuel temperature and enthalpy reaches maximum value around 2% and 10%, respectively.

Objectives The recent guideline for the evaluation and management of Chronic Kidney Disease recommends assessing GFR employing equations based on serum creatinine; despite this, creatinine clearance 24-hour urine collection is used routinely in many settings. In this study we compared the classification assessed from CrCl (creatinine clearance 24 h urine collection) and e-GFR calculated with CKD-EPI or MDRD formulas. Design and methods In this retrospective study we analyze consecutive laboratory data: creatinine clearance 24 h urine collection, serum creatinine and demographic data such as sex and age from 15,777 patients > 18 years of age collected from 2011 to 2013 in our laboratory at Careggi Hospital. The results were then compared to the estimated GFR calculated with the equations according to the recent treatment guidelines. Consecutive and retrospective laboratory data (creatinine clearance 24 h urine collection, serum creatinine and, demographic data such as sex and age) from 15,777 patients > 18 years of age seen at Careggi Hospital were collected. Results Comparison between e-GFR calculated with CKD-EPI or MDRD formulas and GFR according CrCl determinations and bias [95% CI] were 11.34 [− 47,4/70.1] and 11.4 [− 50.2/73] respectively. The concordance for 18/65 years aged group when compared with e-GFR classification between MDRD vs CKDEPI, MDRD vs CrCl and CKD-EPI vs CrCl were 0.78, 0.34, and 0.41 respectively, while in the 65/110 years aged group the concordance Kappas were 0.84, 0.38, and 0.36 respectively. Conclusions The use of CrCl provides a different classification than the estimation of GFR using a prediction equation. The CrCl is unreliable when it is necessary to identify CKD subjects with decrease of GFR of 5 ml/min/1.73 m 2 /year.

Antigens of both Dirofilaria immitis and Wolbachia symbiont bacteria are implicated in the inflammatory pathology of heartworm infection. The aim of the present study was to compare the stimulatory capacity of in vitro cultures of vascular endothelial cells by the adult somatic antigens of D. immitis (DiSA) and the recombinant form of the Wolbachia surface protein (rWSP), during the first 24 h of stimulation. Our results indicate a different stimulatory activity of the two antigens. Both the DiSA and rWSP stimulate the production of the enzymes responsible of the arachidonic acid metabolism, cyclooxygenase-2, 5-lipoxygenase (5-LO), and leukotriene B4. Only DiSA stimulates the production of prostaglandin E2. Related to the adhesion molecules, the DiSA stimulates the expression of intercellular adhesion molecule-1 (ICAM-1) and platelet endothelial cell adhesion molecule-1 (PECAM-1), whereas rWSP stimulates ICAM-1, PECAM-1, and vascular cell adhesion molecule-1 (VCAM-1). Expression of E-cadherin and vascular endothelial growth factor also were stimulated by rWSP. Neither of the two antigens altered the basic physiological mechanisms of endothelial cells, such as cell proliferation, cell cycle, or apoptosis. The biological and pathological significance of these finding are discussed.

The analysis of the polarographic, voltammetric and coulometric results shows that the overall reduction mechanism of benzamide occurs with the cleavage of the CN bond. However, the first step of the electrochemical process leads to the formation of a radical anion which undergoes protonation by another benzamide molecule in DMF and DMSO or by the solvent in CH 3 CN and C 2 H 5 OH. Theoretical calculations have been performed to clarify the mechanism. Halobenzamide reduction involves the Chalogen bond breaking as the first reduction step to give benzamide.

The electrochemical behaviour in protic and aprotic solvents of some tosylaminoacids bearing a lateral electroinactive chain confirms that the reduction mechanism conforms to that one already proposed for tosyl- and dansylglycine and benzenesulphonamide derivatives. The E 1 2 value reveals to be a good structural index and relationships between empirical and calculated structural parameters show that the presence of the carboxylate group in tosylaminoacids causes an increase of NH bond acidity with respect to benzenesulphonamide derivatives. The pK values of the amide group are influenced by the kind of the lateral chains and by the position of carboxylic group in the molecular frame.

Summary The polarographic behaviour of some para-substituted phenylmethylsulphoxides has been examined in different solvents and mixtures. Different substituents do not affect the reduction mechanism proposed for -SO-CH3 and every compound follows the Hammett-Zuman equation. This even applies to the p-Cl derivative, for its half-wave potential is determined by the first electron transfer; its reduction mechanism is, however, affected by adsorption on the electrode. The influence of the dielectric constant on half-wave potentials in several solvents and mixtures has been evaluated.

The complex formation reactions of glycine, N-acetyl- and N-benzoyl-glycine with the Zn(II) ion were investigated using the polarographic method in aqueous and ethanolic solution to identify the number and type of complex species present in solution and to calculate their stability constants. In aqueous basic solution (pH 6–9), only the glycinate anion reacts with the metal ion forming three complexes of the type ZnL+, ZnL2 and ZnL−3. On the contrary in ethanolic solution all three amino acids react; the N-protected amino acid anions form four complexes of the type ZnL+, ZnL2, ZnL−3 and ZnL2−4, while in the presence of the glycine anion two complexes only of the type ZnL+ and ZnL2 were identified. The results obtained for these systems in aqueous and ethanolic solution, discussed in comparison with those of the corresponding cadmium(II) systems, also suggest an amino acid coordination to the metal ion through different coordination sites in the solvents examined.

The analysis of polarographic and coulometric results shows that the overall reduction mechanism of chlorobenzenesulphonamide derivatives occurs with the cleavage of the CCl bond followed by the reduction of the benzenesulphonamide involving the SN bond breaking. However, the E sol1 2 values fit the structural relation E 1 2 -ELUMO for the series of benzenesulphonamides and not that of the cholorobenzene derivatives and the shape of the LUMO of cholorobenzenesulphonamides is similar to that of the benzenesulphonamide, so that it is sensible to suggest that the first step of the reduction mechanism is the same for all the benzenesulphonamide derivatives and involves the CSN moiety of the molecules.

The polarographic behaviour of Zn2+ and CD2+ and their complexes with glycine, N-acetyl and N-benzoylglycine has been studied in DMSO, CH3CN and DMF; the results have been compared with those previously obtained in H2O and C2H5OH. The effect of the solvent properties on the reduction of those systems has been explained in terms of the electron pair donor (EPD) and of electron pair acceptor (EPA) strength of the solvent itself. The higher the donor number (DN), the more negative the E 1 2 value both of the free metal ions and the complexes. Moreover, the stability constants of the complexes, polarographically determined, seem to be related to the acceptor number (AN) of the solvent.

The electrochemical reduction of OSO 2 NH 2 and its ortho, para and meta amino derivatives was examined in aprotic medium (CH 3 CN) with varying experimental conditions, i.e. drop time, concentration and temperature. It has been shown that the reduction process is irreversible and controlled by diffusion at small values of concentration and low drop times, while the whole process is controlled by an adsorption step at larger values of concentration and drop times. The reduction mechanism, proposed by Horner for sulphonamides of the type XOSO 2 NR 1 R 2 , was confirmed and shown always to involve the S-N bond cleavage. Half-wave potentials and electrokinetic parameters were correlated with some theoretical and experimental structural indexes. Even if the correlation is fairly good and confirms the validity of the theoretical model assumed, it does not enable the pharmacological behaviour of the three isomers to be differentiated.

The polarographic study of 21 N1-substituted sulfa drugs has shown that the overall reduction process on an Hg electrode depends on the protonicity of the solvent and on the number of substituents on the N1 nitrogen (mono- or disubstituted). However, these features do not appear to influence the E1/2 values as they maintain a strict correlation in aprotic (DMF) vs. protic medium (C2H5OH), regardless of the number of substituents on amidic nitrogen. It has also been shown that the N1-substituents cause large shifts of the half-wave potential, so ΔE1/2 can be used as a kind of “substituent constant”. Correlations with pKa and spectroscopic data, as well as with the antibacterial potency of these compounds, have been obtained and discussed.

Summary A series of 1000 cases was selected, on the basis of a clinical andlor post-mortem diagnosis of cancer, out o f 4927 autopsies performed at the Institute of Pathologic Anatomy and Histopathology of Turin University. The comparison between clinical and post-mortem diagnoses pointed to an overall concordance with regard to the correct identification of a malignancy as the underlying cause of death of 75%; if the correct identification of type and primary site of the tumor was also taken into account, the concordance was only 56%. The rate of false-positive and false-negative diagnoses, the confirmation rate and sensitivity index of clinical diagnoses, and the error of estimate of the overall frequency of the different types of tumors were computed. Pancreas, liver and biliary tract tumors appear to be the most difficult to identify correctly during life; also lung, stomach and colorectal cancers, lymphomas and leukemias show fairly high rate of clinical errors. Breast cancer, tumors of the nervous system and colorectal cancers appear to be overnotified. These results seem to underscore the necessity of being very careful in drawing conclusions on the frequency and distribution of the different types of cancer on the basis of current mortality statistics.

The electrochemical behaviour in DMF of sulphapyridine and its N1-methyl derivative was studied by means of polarographic, coulometric and cyclic voltammetric methods. Polarographic analysis pointed out the effect of the adsorption on the reduction mechanism and allowed to settle the range of concentration and dropping time in which E12 is only determined by the electron transfer; in these conditions E12 may be regarded as a structural parameter, so that a value of σ1 related to the effect of the pyridinil group on the reactive site was determined. Coulometric measurements let the reduction products be characterized, the overall reduction mechanism came out quite similar to that of other benzenesulphonamide derivatives. Moreover, the cyclic voltammetric behaviour showed that the reduction is affected also by the adsorption of the reduction products on the electrode surface.

The polarographic study of a series of N-substituted benzenesulphonamides and their p -amino derivatives, in aprotic and protic media (CH 3 CN, dimethylformamide, C 2 H 5 OH), has shown that the electrochemical reduction of these compounds involves the S−N bond cleavage and follows the mechanism proposed by Cottrell and Mann. It has also been shown that the effect of the substituents on the amidic nitrogen on the half-wave potential is independent of the protonicity of the solvent used, so the E 1/2 value can be regarded as a good structural index. From the polarographic data, a series of polar inductive substituent constants is obtained, the validity of which has been proved also by comparison with other experimental physicochemical parameters of these compounds related to their molecular structure.

The complexation reactions of glycine, N-acetyl- and N-benzoyl-glycine with the Cd 2+ ion were studied as a model for metal-protein interactions, using polarographic techniques in aqueous and ethanolic solution at 0.1 M NaclO 4 , as base electrolyte, to identify the number and type of solution complex species and to calculate their stability constants. In aqueous solution three complexes of the forms CdL + , CdL 2 and CdL - 3 coexist in the pH range 7–10 for the glycine, while the N-protected amino acids do not react under any pH conditions. In ethanolic solution four complexes of the forms CdL + , CdL 2 , CdL - 3 and CdL 2- 4 coexist for the N-protected amino acids, while for the glycine the CdL 2- 4 complex prevails. A Hammett relationship is observed between the reversible E 1 2 of β 4 (stability constant)values versus the σ constants for the substituents on the amino group. A coordinative hypothesis for the complexes in solution is also suggested.

The adsorption of two N1-sulfanilamide derivatives, N1-2-pyrimidinyl and N1-2(4,6-dimethyl)pyrimidinyl, was studied by a differential capacitance method at pH=12 at the dropping mercury electrode. The area occupied by each molecule of these compounds, adsorbed at the mercury-electrolyte solution interface, corresponds well to the area expected for a molecule adsorbed flat on the electrode with its pNH2O-S moiety. This is confirmed by the correlation between the adsorption free energy (at constant potential) and the polarographic “substituent constant” which reflects the effect of N1-substitution on the electronic structure on the pNH2O-S moiety. Finally, the good linear correlation between ΔGads0 values and the activity parameters related to the biological activity of sulfanilamides suggests the presence of an adsorption step in the mechanism of action able to account for the different bacteriostatic potencies of the compounds.

Adsorptions of ΦCOOH, ΦSO 2 NHΦ and ΦSO 2 NH pyrimidine were studied by a differential capacitance method at pH=12 at the dropping mercury electrode. The interfacial behaviour of each compound was compared with that of the corresponding p -amino derivative: The experimental γ max values are approximately the same, while the experimental −Δ G ads o , at constant potential, are lower by a constant contribution. Moreover, the two oxygen atoms still seem to be directly involved in the adsorption process. Finally, the relevance of the p -NH 2 substitution on the pharmacological properties of these compounds is discussed.

Summary The effect of various H2O−C2H5OH mixtures on the formation of complexes of Cd2+ with pyridine and on the reduction kinetics of the system [Cd(Py)n]2+/Cd(Hg) has been studied. It has been shown that it is not so much the presence of complexes with pyridine that affect the reduction kinetics as the changes brought about in the electrode-solution double layer by the pyridine itself.

By means of polarographic and potentiometric measurements it was shown that Co(II) ion and N-benzyloxycarbonyl-L-tryptophan form in alkaline methanolic solution only one complex with a 1:2 metal to ligand ratio. In solution, so that in the solid state, the aminoacid is coordinated only through the carboxylate group. In excess of ligand and NaOH, the complex Co(Z-trpO) 2 coordinates two OH ions and forms the species [Co(Z-trpO) 2 (OH) 2 ] 2− which behaves as an intermediate species in the formation of Co(II) hydroxide.

In the copper(II) ionN-tosylglycinate system, in both the solid state and in aqueous solution, it was suggested that the ligand presents the properties of both L-α-amino acids [1] and their N-acetyl or N-benzoyl-derivatives [2] depending on the pH of the media [3]. In this paper we report an investigation on the same system in ethanolic solution in order to compare the coordination behavior of this amino acid with those of N-acetyl and N-benzoyl-amino acids also in this media. From ethanolic solution two compounds of formula [Cu(TsglyH)2]n (green) and Na2[Cu(Tsgly)2] (blue) (TsglyH and Tsgly = N-tosylglycinate monoanion and dianion, respectively) were isolated. In the latter complex, which is similar to a compound previously separated from aqueous solution, the ligand acts as bidentate through the carboxylate oxygen atom and the deprotonated sulphonic nitrogen atom. For the green compound the crystal structure was also determined. Crystals are monoclinic, space group P21/n, with Z = 4 in a unit cell of dimensions: a = 24.655(3), b = 7.697(2), c = 12.378(3) A, and β = 87.34(8)°, and R = 0.052. The structure (Fig.1) is built up of one dimensional polymeric chains of binuclear units, showing the cupric acetate structure, linked via CuO (sulphonic) bonds. Its magnetic and spectroscopic properties are interpreted on the basis of the crystal structure. The exchange integral (−2J) is 353 ± 4 cm−1. In ethanolic solution at metal ion concentrations similar to those normally found in biological systems, by polarographic measurements, for CNaOH/CComplex ratios between 1 and 3 the Cu(TsglyH)2 species is the only present, while for ratios greater than 4 the Cu(Tsgly)2−2 prevails. The main conclusions from this work are: In ethanolic media the N-tosylglycine parallels the behavior in aqueous solution, even if more complicated equilibria are present in this last solvent. The separation of only two solid compounds from ethanol with respect to the four from aqueous solution also confirm this. These results, and those previously observed for the N-acetyl and N-benzoyl-amino acids [2], suggest as a general rule that the ethanolic media enhances the behavior as simple carboxylate ligands of these amino acids, favouring the separation of compounds which possess dimeric arrangement of the copper(II) acetate type with strong antiferromagnetic exchange. Nevertheless, in the N-tosylglycinatecopper(II) ion system in ethanolic solution in the experimental conditions (i.e. at metal ion concentrations close to those of biological systems), there is no evidence for a binuclear species.

It is known that cadmium has a chemical behavior very similar to that of zinc, and so the normal process of zinc metabolism can be blocked and distorted by cadmium. There are a number of zinc-dependent enzymes that could be susceptible in vivo to cadmium interference. In this work we have compared the coordination properties of glycine, N-acetyl and N-benzoyl-glycine toward Zn(II) and Cd(II) ions in aqueous and ethanolic solutions by means of polarographic measurements, to determine the number, type and stability constants of solution complexes. In aqueous solution only the glycine reacts with the metal ions forming three complexes [ML+, ML2, ML−3 (M = Zn, Cd)] in the 7–9 pH range. The stability constants of Zn(II) complexes are greater than those of the corresponding Cd(II) complexes, according to Irving-Williams sequence [1]. The different coordination ability of the glycine with respect to the other amino acids may be attributed to the fact that the glycine, coordinating through the amino and carboxylate groups, forms stable five-membered chelate rings. N-acetyl- and N-benzoyl-glycine form four complexes [ML+, ML2, ML−3, ML−−4 (M = Zn, Cd)] in ethanolic solution. The stability constants of Zn(II) complexes are greater than those of Cd(II) complexes. In ethanolic solution a stability of Zn(II) glycine complexes greater than that of Cd(II) glycine complexes is also found. In fact four complexes exist for Cd(II) also in presence of glycine excess, while Zn(II) forms only two complexes (ZnL+, ZnL2), since with a metal glycine ratio greater than 1:2 a solid compound precipitated. A linear correlation obtained by plotting E 1 2 and Inβ4 (the stability constant of the ML−−4 complex) versus σp (the substituent constants on the amino group) suggests that, in ethanolic solution, in the metal coordination all the amino acids studied involve the same coordination sites.