Investigation of fiber/matrix adhesion: test speed and specimen shape effects in the cylinder test

The cylinder test, developed from the microdroplet test, was adapted to assess the interfacial adhesion strength between fiber and matrix. The sensitivity of cylinder test to pull-out speed and specimen geometry was measured. It was established that the effect of test speed can be described as a superposition of two opposite, simultaneous effects which have been modeled mathematically by fitting two parameter Weibull curves on the measured datas. Effects of the cylinder size and its geometrical relation on the measured strength values have been analyzed by finite element method. It was concluded that the geometry has a direct influence on the stress formation. Based on the results achieved, recommendations were given on how to perform the novel single fiber cylinder test

TECNICA ESTRATTIVA E STORIA NELLA CAVA MADRE DI CANDOGLIA

La nota presenta una sintesi storico tecnica delle coltivazioni di marmo rosa destinato alla costruzione e manutenzione del Duomo di Milano. Le cave a ciò destinate si trovano all’imbocco della Val d’Ossola e, in particolare negli ultimi 40 anni, hanno visto lo sviluppo della principale di esse, la Cava Madre, una caverna sotterranea di ragguardevoli dimensioni. L’aspetto storico della coltivazione riguarda le modalità con cui venne riservato a tale contesto estrattivo la prerogativa di fornitore della Veneranda Fabbrica del Duomo, nonché le tecniche estrattive, di trasporto e di lavorazione per strutture e fregi del duomo. Negli ultimi 15 anni, l’estrazione si è concentrata sull’imbocco della caverna, sviluppando la tecnica del taglio con filo e con tagliatrice a nastro, dopo aver realizzato un’approfondita modellazione numerica degli scavi, una caratterizzazione geomeccanica dei materiali ed aver approntato un articolato sistema di monitoraggio geotecnico, tuttora attivo ed aggiornato, tale da poter seguire lo sviluppo tenso deformativo della caverna

Metabolic effects of diltiazem and atenolol: results from a randomized, double-blind study with parallel groups

In a randomized, double-blind study (n = 58) with parallel groups, the effects of diltiazem (mean dose 329 mg/day) and atenolol (mean dose 67 mg/day) on carbohydrate and lipoprotein metabolism in hypertensive patients were compared. The mean systolic blood pressure (SBP)/diastolic blood pressure (DBP) reductions in the supine position were similar and satisfactory, 9/11 and 11/9 mmHg during atenolol and diltiazem treatment, respectively. Insulin-mediated glucose uptake, measured with the euglycaemic insulin clamp technique, decreased during atenolol treatment, from 7.1 to 5.6 mg/kg per min (P = 0.05). but not during treatment with diltiazem (initial value 6.8, final value 6.7 mg/kg per min; P greater than 0.8). Treatment differences between groups were statistically significant (P less than 0.05). During atenolol treatment there was a slight but significant increase in plasma glucose in the fasting state (P less than 0.05) and at the end of an intravenous glucose tolerance test (IVGTT; P less than 0.01), and in plasma insulin at the end of IVGTT (P less than 0.05). Despite increased insulin resistance the increase in insulin response was small, suggesting inhibition of insulin release. The insulin peak was decreased by 13% during diltiazem treatment (P less than 0.05). The concentrations of very-low and low-density lipoprotein triglycerides increased, whereas high-density lipoprotein cholesterol decreased and low-density lipoprotein cholesterol was unaffected during atenolol treatment. In conclusion, there was no difference between the antihypertensive effects of atenolol and diltiazem, but atenolol decreased insulin sensitivity and altered the lipid profile, thus possibly increasing the risk of diabetes mellitus and theoretically reducing the benefits of blood pressure reduction with regard to risk of coronary heart disease

Una grande caverna per l'estrazione di pietra ornamentale: il caso della Cava Madre del Duomo di Milano a Candoglia (VCO)

The geological, geo-mechanical and numerical studies carried out for the static design of the underground exploitation cavern of the Cava Madre of Candoglia (VCO, Italy) are presented and discussed in the paper. This underground cavern was constructed for the mining exploitation of a large sub-vertical vein of pink marble that was necessary for the construction of Milan Cathedral. This marble orebody was gifted to the Milan Cardinal by the Duke Gian Galeazzo Visconti in the 1387 and the exploitation is today active (only in the underground cavern and no more in open pits) since it is necessary to provide the marble (slabs, blocks for the statues, etc.) for the cathedral maintenance. The cavern started from the mountain side and entered sub-horizontally inside the mountain for a length of about 50m. Now the cavern has a width of more than 20m and a variable height that, in the portal area, is of about 40m. Due to a stability problem of the cavern wall that occurred more than ten years ago in the deepest portion of the cavern, it was decided to restart the exploitation works in the portal area where detailed “geo” investigations have discovered a large portion of very good marble. To permit a safe extraction of this new portion of the orebody it was necessary to develop both side investigations and numerical computations. Three dimensional and two dimensional FLAC models were developed to understand the static conditions of the cavern in the present situation and after the development of the forecasted exploitation. Thanks to a very good monitoring of the cavern during the years it was also possible to carry out a detailed back analysis that permitted to validate the quality of the numerical results. Before carrying out the new mining works it was necessary to demolish several reinforced concreted beams that were built up in the seventies and that were not able to fulfil the displacements induced by the new excavations as shown by the numerical model results. The design of the new beams with a larger cross section than the previous ones is discussed in the paper together with the numerical model results after the development of the new excavations

Molecular Background and genotype-phenotype correlation in APECED patients from Campania and in their relatives.

BACKGROUND: Autoimmune-polyendocrinopathy-candidiasis- ectodermal-distrophy (APECED) is a recessive disease, caused by mutations in the AutoImmune REgulator (AIRE) gene. Different mutations are peculiar of particular populations. In Italy, 3 hot spots areas where APECED shows an increased prevalence, have been identified in Sardinia, Apulia, and in the Venetian region.AIM: In this study, we analyzed AIRE mutations and genotype-phenotype correlation in APECED patients originating from Campania and in their relatives.PATIENTS AND METHODS: In 6 patients affected with APECED clinical findings, genetic analysis of AIRE, and APECED-related autoantibodies were performed.RESULTS: All patients carried at least 1 mutation on exon 1 or on splice-site flanking exon 1. Two siblings carried a complex homozygous mutation [IVS1 + 1G>C; IVS1 + 5delG] on intron 1; 2 patients were compound heterozygous for [T16M]+[W78R] (exons 1+2); 1 patient was compound heterozygous for [A21V]+[C322fs] (exons 1+8) and another was homozygous for [T16M]+[T16M] on exon 1. Expression of the disease showed wide variability while circulating autoantibodies paralleled to phenotype in each patient. Analysis of relatives allowed the identification of 8 heterozygotes. None of heterozygous subjects presented major findings of APECED.CONCLUSIONS: Mutations localized on exon 1 and the region flanking exon 1 are common in APECED patients originating from Campania. Genotype-phenotype correlation failed to reveal a relationship between detected mutations and clinical expression. Mutations in heterozygosis in AIRE gene are not associated to major findings of APECED