A cheap protocol for colour measure and for diagnostic in planning a cultural heritage restoration. Case study: main façade of Palazzo Governi (Cagliari, Sardinia, Italy).

Due to the bad state of conservation, "Palazzo Governi", a seventeenth-century building located in the old town district of "Stampace" in Cagliari (Sardinia, Italy), was subjected to restoration. Thus, according to the Italian Law n. 1089, the main façade colour must be reproduced, and therefore, its identification was required. The available samples looked fairly degraded, in particular as an easy plaster to crumble; so, some other analyses able to identify the degradation cause were performed. Two different approaches were adopted to attain the first goal, the visual colour assessment by a sensory panel (subjective) and the instrumental measurement by colorimetry (objective). Ion chromatography and inductively coupled plasma-optical emission spectroscopy analyses, as well as conductivity and pH measurements, were performed to evaluate the presence of water-soluble salts inside the plaster, as possible cause of degradation; the binder/aggregate ratio was also evaluated. A full mineralogical and petrographic characterisation of the materials constituting the samples, as well as the identification of their stratigraphy and some other morphologic and structural features suitable to highlight eventual forms of degradation, were performed by optical microscopy. Scanning electron microscopy coupled to X-ray microanalysis was been also used in order to confirm and/or to integrate data obtained by optical microscopy. The samples have been compared with two samples coming from two other buildings, also located in Sardinia, that looked in good conservation state. The results evidenced that the causes of degradation come from a high salt (especially sulphate) content and a scarce presence of binder in the plaster that can be imputed to a wrong initial composition and/ or to a leaching by acidic rain.

Direct Route to Colloidal UHMWPE by Including LLDPE in Solution during Homogeneous Polymerization of Ethylene.

The usual aggregation and precipitation driven by crystallization of nascent PE during homogeneous polymerization of ultra-high molecular weight polyethylene (UHMWPE) is inhibited by including linear low-density polyethylene (LLDPE) in the catalyst solution prior to addition of ethylene monomer. Co-crystallization of newly formed PE and dissolved LLDPE creates a polymer brush on the fold surfaces of the nascent crystallites. Consequently, aggregation is inhibited by steric stabilization. Scanning electron microscopy (SEM) images show that individual lamellae (approximately 10-20 nm thick) typically have lateral dimensions of 0.5 µm × 3.5 µm and form "bowtie" shaped stacks that are approximately 200-500 nm thick. This simple method for stabilizing nascent crystals against precipitation is enabling fundamental studies of their metastable "disentangled" state and may open scalable routes to compounding UHMWPE.

[Quaternary ammonium salts in gynecology and obstetrics]. / I sali quaternari di ammonio in ginecologia ed ostetricia.

We have summarized chemical, physical, and microbiological characteristics of Quaternary Ammonium Salts: particularly, benzalchromium chloride and didecyl-dimethyl-ammonium chloride characteristics were analyzed. These compounds may act as antimicrobial agents in different way: 1) they are surface-active agents and will denature protein or cause dissociation of an enzyme from its prosthetic group; 2) they may alter the cell permeability of bacteria and yeasts; 3) they may stimulate the glycolysis reaction and 4) may inhibit oxidation of lactate. These latest activities may play a role in maintenance of physiologic microbial ecology of vagina or in the re-establishment of the vaginal ecosystem after vaginitis or vaginosis. We have also summarized the physiologic variation of vaginal ecosystem during the different phases of women's life and the microbiology of vagina during vaginitis and vaginosis. The results of more recent studies about the therapeutic role of quaternary ammonium compounds in vulvo-vaginal infections an in vaginosis are synthetically reported. We concluded that quarternary ammonium compounds are efficacious, handy and safe, in obstetrics and gynecology. A very good compliance and low costs of these compounds suggest that they may be used alone as well in association with specific antimicrobial agents in the treatment of most of gynecological infections, and particularly in bacterial vaginosis.

[Autoimmune thrombocytopenia and pregnancy]. / Trombocitopenia autoimmune e gravidanza.

Immune thrombocytopenic purpura (ITP) is an autoimmune disorder with its highest frequency in young women in the reproductive years. An antepartum diagnosis of maternal thrombocytopenia has become more common because platelet counts are now included with routine complete blood cell counts. Sometimes platelet autoantibodies facilitate increased platelet destruction by the reticuloendothelial system especially the spleen. These autoantibodies (IgG) can cross the placenta and place the fetus at risk for thrombocytopenia and, sometimes, serious bleeding problems such as intracranial hemorrhage can occur. The treatment is performed by corticosteroids (prednisone) or intravenous immune gammaglobulin. Four patients with thrombocytopenia during pregnancy underwent medical treatment (prednisone 1 mg/kg/die). The results were successful. In one case only we did not have a clinical response after corticosteroid therapy. There were no intracranial hemorrhages; however the risk for the patients and fetal or neonatal hemorrhage is much lower than thought. Corticosteroid treatment is the first choice, but sometimes it can give a clinical negative response.