Biomedical subjects

Matteo Manfredini

Publications and source records attributed to Matteo Manfredini.

6 recordsLinked to original sources

PubMed2004

A chemometric approach to the comparison of different sample treatments for metals determination by atomic absorption spectroscopy in aceto Balsamico tradizionale di Modena.

A comparison of different digestion procedures has been carried out for the analysis of metal concentration in samples of vinegars and Aceto Balsamico Tradizionale of Modena (ABTM) coming from an unique barrel set. In particular, classical wet, dry ashing, and closed vessel microwave digestion procedure have been utilized and compared for each investigated species. In a few cases, direct metal determination on ABTM (without treatment procedure) is proposed as possible alternative to sample manipulation. Flame atomic absorption spectrometry was used for the quantification of iron and zinc, while graphite furnace atomic absorption spectrometry was used for all the other elements (i.e., chromium, manganese, cobalt, nickel, copper, cadmium, and lead). The comparison among the different sample treatments was carried out by the use of statistical and chemometric tools. In particular, principal component analysis and ANOVA approaches were used to discriminate between the diverse analytical methods. Furthermore, for all the dissolving techniques, the analytical metal recovery was always evaluated by the application of the recovery function on the same sample matrix. In general, the recoveries were fairly good, ranging from 90 to 103%, except for Cd and Pb with dry ashing, which showed recovery values close to 55% and 67%, respectively. As regards the metals concentration of the investigated samples, the experimental data reveal for some species the presence of concentration slightly over the legal limit fixed for wine and wine vinegar.

Acetic Acid↗

PubMed2003

The use of parish marriage registers in biodemographic studies: two case studies from 19th-century Italy.

No previous studies have critically evaluated the representativeness or reliability of parish marriage registers for biodemographic studies of historical Italian populations. Because of the widespread Italian custom of spouses settling down in the groom's parish after getting married in the bride's, such registers do not contain any information on wife-exogamous unions. This fact affects not only the number of marriages considered, but also any estimates of the biodemographic parameters usually assessed in these types of studies, especially when open populations are considered. Due to the richness of the parish archives for two populations in central Italy, it was possible to retrieve from the Status Animarum (Register of Souls) information concerning the missing data regarding marriages. Consequently, it was possible to compare values of marital structure indices obtained using only data from marriage registers with the corresponding figures computed using either the complete data series of marriages or solely that of resident couples. The results demonstrate the existence of significant variations in the figures for the exogamy rate, as well as in the number of new family names introduced by marriage. In addition, F and RP values showed important but nonhomogeneous variations.

Adolescent↗

PubMed2002

Beta-functionalised polythiophenes as microelectrode modifiers in low conductive media.

A study on polythiophene coated microelectrodes is reported, the goal being that of checking the capability of these electrochemical systems to work in low conductive media. The possibility of electrochemically p-doping the polymer in the presence of very low concentrations or even in the absence of supporting electrolyte in the solution is ascertained, opening the way to the use of similar systems in pure solvent media. This result is obtained in such conditions that the presence of residual charges--and corresponding counterions--trapped inside the film coating can be reasonably hypothesised.

Electric Conductivity↗

PubMed2002

Temperature and composition dependence of the refractive indices of the 2-chloroethanol + 2-methoxyethanol binary mixtures.

Measurements of the refractive index n for the binary mixtures 2-chloroethanol + 2-methoxyethanol in the 0 < or = t/degree C < or = 70 temperature range have been carried out with the purpose of checking the capability of empirical models to express physical quantity as a function of temperature and volume fraction, both separately and together, i.e., in a two independent variables expression. Furthermore, the experimental data have been used to calculate excess properties such as the excess refractive index, the excess molar refraction, and the excess Kirkwood parameter delta g over the whole composition range. The quantities obtained have been discussed and interpreted in terms of the type and nature of the specific intermolecular interactions between the components.

Ethylene Chlorohydrin↗

PubMedDate not supplied

Determination of metal concentration in fat supplements for swine nutrition by atomic absorption spectroscopy.

The presence of some essential and toxic metals in fat supplements for swine diet was investigated. Collected samples represented a relevant production of the Italian industry. In particular, some samples were enriched with antioxidants or waste cooking oils. The method for the determination of Ca, Cu, Cd, Fe, Mg, Mn, Ni, Pb, and Zn in fat samples was developed by means of a certified reference material (CRM 186) and a representative fatty sample (RFS). All samples were digested in closed vessels in a microwave oven and then analyzed by flame atomic absorption or graphite furnace atomic absorption spectrometry. The entire analytical method provided a satisfactory repeatability and reproducibility confirmed by agreement between the experimental recovery data obtained for the CRM 186 sample and, with the method of standard additions, for the RFS material. The samples generally showed a small amount of metals compared with the recommended daily intake for the essential elements. On the other hand, some samples contained a significant concentration, from an analytical point of view, of Cd, Ni, and Pb. Principal component analysis (PCA) was applied to inspect the experimental data obtained from samples analysis. Basically no differences were detected in terms of metal concentration among the fat supplements analyzed.

Animal Feed↗

PubMedDate not supplied

The Bourgeois-Pichat's biometric method and the influence of climate: new evidences from late 19th-century Italy.

This paper examines to which extent seasonal and climatic conditions might affect the reliability of the Bourgeois-Pichat's method. Other scholars have already argued on this issue, but although climate has often been claimed to explain part of the differentials in mortality figures among Italian regions, to date its impact has not actually been recognized and quantitatively evaluated. To test such hypothesis data at the regional level from late 19th-century Italy have been analyzed. Our analysis of the biometric components revealed a strong bias in the estimates of the endogenous and exogenous components in the first month of life. Variations in infant mortality among Italian regions correlated with variations in the endogenous levels rather than in the exogenous levels of infant (neonatal) mortality, as it was expected owing to the infective nature of the diseases climate might induce. Specifically, Northern and colder regions featured high figures for both neonatal mortality and the endogenous component, while the opposite scheme applied to the Southern, more temperate regions. Finally, the reasons for such misleading results were investigated. It emerged that the model's assumption of a constant and invariant proportion of neonatal exogenous deaths to the total amount of exogenous deaths was not matched by the Italian data. This situation caused the excess neonatal exogenous mortality, especially that induced by cold climate in Northern regions, to be wrongly counted in the endogenous component.

Algorithms↗