The Venetian Plain is known for areas with high concentrations of arsenic (As) in groundwater (up... more The Venetian Plain is known for areas with high concentrations of arsenic (As) in groundwater (up to more than 400 μg/L; exceptionally 647µg/L, in selected areas). A study area was chosen, north of Padua, which exhibits typical residential, industrial, and agricultural characteristics similar to most Western countries and lacks hydrothermal, volcanic, or anthropogenic sources of arsenic. The pilot area was the focus of several studies which are reviewed in this note. The objectives of the studies were to verify the distribution of As concentrations in groundwater and sediments (mineralogical and geochemical analysis of groundwater sediments and of filtered and unfiltered groundwater) and to model the mobility of arsenic arising from water-rock interaction. The grain size of aquifer reservoirs includes gravel, sand, silt, and clay. The amount of organic matter in the aquifer sediments of the study area seems peculiar (higher) compared to other plains in the world; it influences the redox potential and the relative concentration of As in groundwater. Arsenic contamination in groundwater and redox conditions varied greatly in the area. Groundwater under oxidizing and highly reducing conditions had much lower arsenic concentrations compared to groundwater under intermediate reducing conditions. Arsenic minerals (such as realgar-pararealgar) occur in aquifer sediments and they were documented in the studied materials by different analytical techniques for the first time in the context of the Italian plains. Since these minerals are rare throughout the world in plain sediments not affected by volcanic or hydrothermal activity, their occurrence is a distinctive feature of the Venetian Plain aquifer. These arsenic minerals were found in peat sediments of the study area, consistent with geochemical modeling results, which require highly reducing conditions for their precipitation from groundwater. Modeling suggests that under oxidizing and up to slightly reducing conditions (from 200 mV to-50 mV), arsenic is adsorbed on solid phases, but a further decrease in redox potential leads arsenic desorption from solids and consequent groundwater contamination (from-50 mV to-250 mV). If the redox potential becomes even more negative (below-250 mV), geochemical conditions are favorable to the formation of arsenic sulfides. The precipitation of the realgar-pararealgar phases, predicted by the geochemical model, proceeds by extracting arsenic from the groundwater and quantitatively accounts for the lower arsenic concentration measured in the highly reducing groundwater of the study area.
In 2020 North Italy suffered the SARS-CoV-2-related pandemic with a high number of deaths and hos... more In 2020 North Italy suffered the SARS-CoV-2-related pandemic with a high number of deaths and hospitalization. The effect of atmospheric parameters on the amount of hospital admissions (temperature, solar radiation, particulate matter, relative humidity and wind speed) is studied through about 8 months (May-December). Two periods are considered depending on different conditions: a) low incidence of COVID-19 and very few regulations concerning personal mobility and protection ("free/summer period"); b) increasing incidence of disease, social restrictions and use of personal protections ("confined/autumn period"). The "hospitalized people in medical area wards/100000 residents" was used as a reliable measure of COVID-19 spreading and load on the sanitary system. We developed a chemometric approach (multiple linear regression analysis) using the daily incidence of hospitalizations as a function of the single independent variables and of their products (interactions). Eight administrative domains were considered (altogether 26 million inhabitants) to account for relatively homogeneous territorial and social conditions. The obtained models very significantly match the daily variation of hospitalizations, during the two periods. Under the confined/autumn period, the effect of non-pharmacologic measures (social distances, personal protection, etc.) possibly attenuates the virus diffusion despite environmental factors. On the contrary, in the free/ summer conditions the effects of atmospheric parameters are very significant through all the areas. Particulate matter matches the growth of hospitalizations in areas with low chronic particulate pollution. Fewer hospitalizations strongly correspond to higher temperature and solar radiation. Relative humidity plays the same role, but with a lesser extent. The interaction between solar radiation and high temperature is also highly significant and represents surprising evidence. The solar radiation alone and combined with high temperature exert an anti-SARS-CoV-2 effect, via both the direct inactivation of virions and the stimulation of vitamin D synthesis, improving immune system function.
Earth's lower mantle most likely mainly consists of ferropericlase, bridgmanite, and a CaSiO3... more Earth's lower mantle most likely mainly consists of ferropericlase, bridgmanite, and a CaSiO3- phase in the perovskite structure. If separately trapped in diamonds, these phases can be transported to Earth's surface without reacting with the surrounding mantle. Although all inclusions will remain chemically pristine, only ferropericlase will stay in its original crystal structure, whereas in almost all cases bridgmanite and CaSiO3-perovskite will transform to their lower-pressure polymorphs. In the case of perovskite structured CaSiO3, the new structure that is formed is closely related to that of walstromite. This mineral is now approved by the IMA commission on new minerals and named breyite. The crystal structure is triclinic (space group: P1) with lattice parameters a0 = 6.6970(4) Å, b0 = 9.2986(7) Å, c0 = 6.6501(4) Å, α = 83.458(6)°, β = 76.226(6)°, γ = 69.581(7)°, and V = 376.72(4) Å. The major element composition found for the studied breyite is Ca3.01(2)Si2.98(2)O9. ...
Nixonite (IMA 2018-133), ideally Na2Ti6O13, is a new mineral found within a heavily metasomatized... more Nixonite (IMA 2018-133), ideally Na2Ti6O13, is a new mineral found within a heavily metasomatized pyroxenite xenolith from the Darby kimberlite field, beneath the west-central Rae Craton, Canada. It occurs as microcrystalline aggregates, 15 to 40 μm in length. Nixonite is isostructural with jeppeite, K2Ti6O13, with a structure consisting of edge- and corner-shared titanium-centered octahedra that enclose alkali-metal ions. The Mohs hardness is estimated to be between 5 and 6 by comparison to jeppeite, and the calculated density is 3.51(1) g/cm3. Electron microprobe wavelength-dispersive spectroscopic analysis (average of 6 points) yielded: Na2O 6.87, K2O 5.67, CaO 0.57, TiO2 84.99, V2O3 0.31, Cr2O3 0.04, MnO 0.01, Fe2O3 0.26, SrO 0.07, total 98.79 wt%. The empirical formula, based on 13 O atoms, is: (Na1.24K0.67Ca0.06)Σ1.97(Ti5.96V0.023Fe0.018)Σ6.00O13 with minor amounts of Cr and Mn. Nixonite is monoclinic, space group C2/m, with unit-cell parameters a = 15.3632(26) Å, b = 3.7782(7...
Raberite, ideally Tl5Ag4As6SbS15, is a new mineral from Lengenbach quarry in the Binn Valley, Val... more Raberite, ideally Tl5Ag4As6SbS15, is a new mineral from Lengenbach quarry in the Binn Valley, Valais, Switzerland. It occurs very rarely as euhedral crystals up to 150 m m across associated with yellow needle-like smithite, realgar, hatchite and probable trechmannite, edenharterite, jentschite and two unidentified sulfosalts. Raberite is opaque with a metallic lustre and has a dark brown–red streak. It is brittle with a Vickers hardness (VHN10) of 52 kg mm–2 (range 50–55) corresponding to a Mohs hardness of 2½–3. In reflected light raberite is moderately bireflectant and very weakly pleochroic from light grey to a slightly greenish grey. It is very weakly anisotropic with greyish to light blue rotation tints between crossed polars. Internal reflections are absent. Reflectance percentages for the four COM wavelengths [listed as Rmin, Rmax, (λ)] are 30.6, 31.8 (471.1 nm), 28.1, 29.3 (548.3 nm), 27.1, 28.0 (586.6 nm), and 25.8, 26.9 (652.3 nm). Raberite is triclinic, space group P1, wi...
Tazzoliite, ideally Ba2CaSr0.5Na0.5Ti2Nb3SiO17[PO2(OH)2]0.5, is a new mineral (IMA 2011-018) from... more Tazzoliite, ideally Ba2CaSr0.5Na0.5Ti2Nb3SiO17[PO2(OH)2]0.5, is a new mineral (IMA 2011-018) from Monte delle Basse, Euganei Hills, Galzignano Terme, Padova, Italy. It occurs as lamellar pale orange crystals, which are typically a few m m thick and up to 0.4 mm long, closely associated with a diopsidic pyroxene and titanite. Tazzoliite is transparent. It has a white streak, a pearly lustre, is not fluorescent and has a hardness of 6 (Mohs' scale). The tenacity is brittle and the crystals have a perfect cleavage along {010}. The calculated density is 4.517 g cm–3. Tazzoliite is biaxial (–) with 2Vmeas of ~50º, it is not pleochroic and the average refractive index is 2.04. No twinning was observed. Electronmicroprobe analyses gave the following chemical formula: (Ba1.93Ca1.20Sr0.52Na0.25Fe0.102+)Σ4 (Nb2.88Ti2.05Ta0.07Zr0.01V0.015+)Σ5.02SiO17[(P0.13Si0.12S0.07)Σ0.32O0.66(OH)0.66][F0.09(OH)0.23]Σ0.32.Tazzoliite is orthorhombic, space group Fmmm, with unit-cell parameters a = 7.4116(...
ABSTRACT Synthesis of gold nanoclusters inside strongly acidic ion exchangers, in beaded forms, i... more ABSTRACT Synthesis of gold nanoclusters inside strongly acidic ion exchangers, in beaded forms, is carried out under different conditions. After metallation with [Au(en)2]Cl3 and reduction with H2 in the absence of any added aqueous phase, Au0/-SO3H nanocomposites are produced that are compared with Au0/-SO3− Na+ ones obtained with NaBH4 as reductant in aqueous medium. Reduction conditions allow control of both distribution and size of the metal nanoclusters. Metal distribution inside the polymer beads appears to be quite homogeneous under the hydrogen reduction conditions and metal nanoclusters size turns out to be size-controlled in the 3–5 nm range. In the case of the action of NaBH4 in water, metal distribution inside the polymer beads appears to be quite peripheral and the metal nanoclusters turn out to be size-controlled but definitely larger, 5–7 nm, than those obtained by action of molecular hydrogen.
This paper is a critical discussing key on previous results of the authors in the field of glassc... more This paper is a critical discussing key on previous results of the authors in the field of glassceramic scaffolds for tissue engineering. With the aim of developing biological substitutes that restore, maintain or improve tissue functionality, glass-ceramic scaffolds were produced starting from a glass system composition enriched with traces of specific elements. The presence of one or more specific ions can modulate the better environmental conditions to favour the growth of specific specialised cells, a necessary prerequisite to originate different kinds of tissues. The main predictable use is for bone reconstruction, but other possible uses are expectable for some specific tissues (cartilage, nerve, tendons, etc.). In order to obtain the best initial tissue integration, a decisive role is played by porosity of the glass scaffold. The glass structure can generally be resorbed, leaving its volume available for tissue nodules which grow and assemble together, producing an equal volume of tissue. In bone, the action is synergically increased thanks to the phenomena of bone conduction and bone induction of the proposed porous bioactive ceramics. On the other hand, glass-ceramic scaffolds have already been appreciated as a superior material for bone healing. Compared to similar hydroxyapatite structures, the glassceramic ones exhibit a greater starting mechanical resistance (useful for surgical manipulations) and differently from the hydroxyapatite ones, they are resorbed more easily in time. This is a good requisite for a material to be used in bone tissue engineering. The ceramic bioactive systems can be used both in bulk and as coatings.
characterized by pain and/ or stiffness of knee and/ or hip. They were included at the first visi... more characterized by pain and/ or stiffness of knee and/ or hip. They were included at the first visit or within 6 months of the first visit to the general practitioner for these symptoms. Study centers comprise ten general and university hospitals located in urbanized and semiurbanized regions in the Netherlands. A special program was developed to minimize loss to follow up, comprising newsletters, website and organizing symposia to present the results and progress of CHECK. An overview of measures that are included in the study can be found at our website www.check-research.com. Results: After 7 years a total of 105 (10%) participants had dropped out. Reasons included loss of interest (21%), comorbidity that complicated participating of CHECK too much (18%), death (12%), contact lost (11%), costs incurred for the study (5%), and other reasons (33%). Dropouts did not differ significantly from other participants in baseline characteristics. Over 7 years follow-up clinical characteristics including pain, stiffness and function of disease-specific (WOMAC) and the subscales of generic self-report questionnaire (SF36) on average did not change significantly, although at least half of the patients experienced radiographic progression. Scoring of 5-year follow up is complete: at this point, 50 % of the participants progressed by at least one Kellgren and Lawrence grade in the knee, and 25% in the hip. Preliminary analyses suggest the existence of several clinical and radiological phenotypes. Conclusions: CHECK is a valuable source of information of early symptomatic OA with a low loss to follow-up and a multidisciplinary approach that allows the collections of high-quality data on clinical, radiological and biochemical variables. DSPCC, diclofenac submicron particle containing capsules; TID, three times daily; BID, twice daily; SF-36, Medical Outcomes Survey Short Form 36 (SF-36), version 2. *P 0.03. Bold values represent scores ! minimally clinically important difference (!2.5 for physical component score; !5.0 for SF-36 domain scores). Data above presented as means however, all P-values are compared with placebo and calculated from least-squared mean changes from baseline.
Journal of Rheumatology; 35:1092-5. ISSN 0315-162X, 2008
Objective. Synovial fluid (SF) may contain a number of crystals that optical microscopy is unable... more Objective. Synovial fluid (SF) may contain a number of crystals that optical microscopy is unable to identify with certainty. Scanning electron microscopy (SEM) was utilized in this study to characterize SF crystals in the context of knee osteoarthritis (OA). Methods. SF was collected from the knees of 25 patients with OA and examined under optical light microscopy. Calcium pyrophosphate dihydrate (CPPD) crystals were assessed by means of compensated polarized light microscopy, while alizarin red S staining was performed to identify apatite (BCP) crystals. All the specimens were also analyzed by SEM and x-ray diffractometry, as gold standards. Results. CPPD crystals were found in 32% and BCP in 24% of the SF examined by SEM. The degree of concordance between polarized light microscopy and SEM was 0.83 for CPPD and 0.46 for BCP (kappa statistic). The secondary and backscatter electron SEM observations allowed identification of silicon dioxide (SiO 2) crystals in 8 out of 10 patients in whom polarized light microscopy revealed irregular and polymorph crystals. Conclusion. SiO 2 crystals cannot be readily identified by their morphology or polarization properties under optical microscopy. Their presence, nevertheless, did not lead to misclassification.
OBJECTIVE Synovial fluid (SF) may contain a number of crystals that optical microscopy is unable ... more OBJECTIVE Synovial fluid (SF) may contain a number of crystals that optical microscopy is unable to identify with certainty. Scanning electron microscopy (SEM) was utilized in this study to characterize SF crystals in the context of knee osteoarthritis (OA). METHODS SF was collected from the knees of 25 patients with OA and examined under optical light microscopy. Calcium pyrophosphate dihydrate (CPPD) crystals were assessed by means of compensated polarized light microscopy, while alizarin red S staining was performed to identify apatite (BCP) crystals. All the specimens were also analyzed by SEM and x-ray diffractometry, as gold standards. RESULTS CPPD crystals were found in 32% and BCP in 24% of the SF examined by SEM. The degree of concordance between polarized light microscopy and SEM was 0.83 for CPPD and 0.46 for BCP (kappa statistic). The secondary and backscatter electron SEM observations allowed identification of silicon dioxide (SiO2) crystals in 8 out of 10 patients in w...
The W (Mo, Sn, Bi) and Cu (Pb, Zn, Ag, Te, Co, Ni, etc.) deposits of Bedovina mark the closure of... more The W (Mo, Sn, Bi) and Cu (Pb, Zn, Ag, Te, Co, Ni, etc.) deposits of Bedovina mark the closure of the MiddleTriassic magmatic cycle of the Predazzo-Monzoni Eruptive Complex, composed of latiandesitic and latibasaltic lavas, monzonitic stocks with shoshonitic affinity, K-alkaline monzosyenitic bodies, and some granitic masses. The mineralization is hosted in a stockwork of veins which intersects the volcanics and, occasionally, granitoid masses, and rarely acidic and mafic veins. Two different metalliferous phases can be recognized, the first mainly wolfram-bearing, the second copper-polymetallic. The wolfram phase is represented by quartz+Kfeldspar+tourmaline veins, with scheelite, minor apatite and rutile, rare cassiterite, and hematite. Sporadic synchysite-(Ce) and molybdenite occur in granite breccias. The copper-polymetallic phase was superimposed to the wolfram one after a brittle tectonic event; it comprises quartz, chalcopyrite, minor pyrite, sphalerite, galena and traces of ...
<p>Seven granitoid rocks were selected due to the well-defined mineralogical content, the t... more <p>Seven granitoid rocks were selected due to the well-defined mineralogical content, the typical the holocrystalline texture, their absent (or very poor) Crystal Preferred Orientations (CPOs), and very-low porosity in order to apply a predictive approach that quantifies and simulates the rock thermal properties by considering the contributions of the mineral phases content. For this purpose, thermal properties of granodiorite, tonalite, granite, and gabbro rock samples were analysed and compared by <em>(i) </em>direct measurements on the bulk rock samples, <em>(ii)</em> by applying Quantitative Phase Analysis (QPA) on Digital Imaging Analysis (DIA) and Xray diffraction Rietveld method, and <em>(iii)</em> by 2D numerical modelling.</p><p>The results confirm the good accuracy of DIA-QPA method by the good according with data refined by X-Ray diffraction Rietveld method, and indicate the potential reliability of the more attractive approach in terms of prediction of the 2D modelling starting by the Quantitative Phase Analysis (QPA) based on Digital Imaging Analyses (DIA). This method, indeed, permits to observe concurrently different mineralogical and textural parameters (such as mineral abundance, grain size and grain size distribution), and it also provides a deep knowledge of the rock&#8217;s thermal behaviour.</p><p>Numerical modelling results indicate that a steady-state condition (SSC) is reached by the combination of thermal contribution given both in terms of modal mineral abundance (mainly controlled by mineralogical phase content related to the quartz occurrence) and in terms of rock texture (by the grain-size dimensions and the geometrical distribution of minerals), considering negligible the porosity.</p><p>The use of predictive models for the evaluation of the rocks thermal properties can find many important applications (e.g., in deep and shallow geothermal systems, as well as in building construction materials), and also permits to evaluate the expected energy performance of borehole heat exchange probes, involving granitoid lithologies, representing a suitable alternative also in cases where direct measures are not possible.</p>
The Venetian Plain is known for areas with high concentrations of arsenic (As) in groundwater (up... more The Venetian Plain is known for areas with high concentrations of arsenic (As) in groundwater (up to more than 400 μg/L; exceptionally 647µg/L, in selected areas). A study area was chosen, north of Padua, which exhibits typical residential, industrial, and agricultural characteristics similar to most Western countries and lacks hydrothermal, volcanic, or anthropogenic sources of arsenic. The pilot area was the focus of several studies which are reviewed in this note. The objectives of the studies were to verify the distribution of As concentrations in groundwater and sediments (mineralogical and geochemical analysis of groundwater sediments and of filtered and unfiltered groundwater) and to model the mobility of arsenic arising from water-rock interaction. The grain size of aquifer reservoirs includes gravel, sand, silt, and clay. The amount of organic matter in the aquifer sediments of the study area seems peculiar (higher) compared to other plains in the world; it influences the redox potential and the relative concentration of As in groundwater. Arsenic contamination in groundwater and redox conditions varied greatly in the area. Groundwater under oxidizing and highly reducing conditions had much lower arsenic concentrations compared to groundwater under intermediate reducing conditions. Arsenic minerals (such as realgar-pararealgar) occur in aquifer sediments and they were documented in the studied materials by different analytical techniques for the first time in the context of the Italian plains. Since these minerals are rare throughout the world in plain sediments not affected by volcanic or hydrothermal activity, their occurrence is a distinctive feature of the Venetian Plain aquifer. These arsenic minerals were found in peat sediments of the study area, consistent with geochemical modeling results, which require highly reducing conditions for their precipitation from groundwater. Modeling suggests that under oxidizing and up to slightly reducing conditions (from 200 mV to-50 mV), arsenic is adsorbed on solid phases, but a further decrease in redox potential leads arsenic desorption from solids and consequent groundwater contamination (from-50 mV to-250 mV). If the redox potential becomes even more negative (below-250 mV), geochemical conditions are favorable to the formation of arsenic sulfides. The precipitation of the realgar-pararealgar phases, predicted by the geochemical model, proceeds by extracting arsenic from the groundwater and quantitatively accounts for the lower arsenic concentration measured in the highly reducing groundwater of the study area.
In 2020 North Italy suffered the SARS-CoV-2-related pandemic with a high number of deaths and hos... more In 2020 North Italy suffered the SARS-CoV-2-related pandemic with a high number of deaths and hospitalization. The effect of atmospheric parameters on the amount of hospital admissions (temperature, solar radiation, particulate matter, relative humidity and wind speed) is studied through about 8 months (May-December). Two periods are considered depending on different conditions: a) low incidence of COVID-19 and very few regulations concerning personal mobility and protection ("free/summer period"); b) increasing incidence of disease, social restrictions and use of personal protections ("confined/autumn period"). The "hospitalized people in medical area wards/100000 residents" was used as a reliable measure of COVID-19 spreading and load on the sanitary system. We developed a chemometric approach (multiple linear regression analysis) using the daily incidence of hospitalizations as a function of the single independent variables and of their products (interactions). Eight administrative domains were considered (altogether 26 million inhabitants) to account for relatively homogeneous territorial and social conditions. The obtained models very significantly match the daily variation of hospitalizations, during the two periods. Under the confined/autumn period, the effect of non-pharmacologic measures (social distances, personal protection, etc.) possibly attenuates the virus diffusion despite environmental factors. On the contrary, in the free/ summer conditions the effects of atmospheric parameters are very significant through all the areas. Particulate matter matches the growth of hospitalizations in areas with low chronic particulate pollution. Fewer hospitalizations strongly correspond to higher temperature and solar radiation. Relative humidity plays the same role, but with a lesser extent. The interaction between solar radiation and high temperature is also highly significant and represents surprising evidence. The solar radiation alone and combined with high temperature exert an anti-SARS-CoV-2 effect, via both the direct inactivation of virions and the stimulation of vitamin D synthesis, improving immune system function.
Earth's lower mantle most likely mainly consists of ferropericlase, bridgmanite, and a CaSiO3... more Earth's lower mantle most likely mainly consists of ferropericlase, bridgmanite, and a CaSiO3- phase in the perovskite structure. If separately trapped in diamonds, these phases can be transported to Earth's surface without reacting with the surrounding mantle. Although all inclusions will remain chemically pristine, only ferropericlase will stay in its original crystal structure, whereas in almost all cases bridgmanite and CaSiO3-perovskite will transform to their lower-pressure polymorphs. In the case of perovskite structured CaSiO3, the new structure that is formed is closely related to that of walstromite. This mineral is now approved by the IMA commission on new minerals and named breyite. The crystal structure is triclinic (space group: P1) with lattice parameters a0 = 6.6970(4) Å, b0 = 9.2986(7) Å, c0 = 6.6501(4) Å, α = 83.458(6)°, β = 76.226(6)°, γ = 69.581(7)°, and V = 376.72(4) Å. The major element composition found for the studied breyite is Ca3.01(2)Si2.98(2)O9. ...
Nixonite (IMA 2018-133), ideally Na2Ti6O13, is a new mineral found within a heavily metasomatized... more Nixonite (IMA 2018-133), ideally Na2Ti6O13, is a new mineral found within a heavily metasomatized pyroxenite xenolith from the Darby kimberlite field, beneath the west-central Rae Craton, Canada. It occurs as microcrystalline aggregates, 15 to 40 μm in length. Nixonite is isostructural with jeppeite, K2Ti6O13, with a structure consisting of edge- and corner-shared titanium-centered octahedra that enclose alkali-metal ions. The Mohs hardness is estimated to be between 5 and 6 by comparison to jeppeite, and the calculated density is 3.51(1) g/cm3. Electron microprobe wavelength-dispersive spectroscopic analysis (average of 6 points) yielded: Na2O 6.87, K2O 5.67, CaO 0.57, TiO2 84.99, V2O3 0.31, Cr2O3 0.04, MnO 0.01, Fe2O3 0.26, SrO 0.07, total 98.79 wt%. The empirical formula, based on 13 O atoms, is: (Na1.24K0.67Ca0.06)Σ1.97(Ti5.96V0.023Fe0.018)Σ6.00O13 with minor amounts of Cr and Mn. Nixonite is monoclinic, space group C2/m, with unit-cell parameters a = 15.3632(26) Å, b = 3.7782(7...
Raberite, ideally Tl5Ag4As6SbS15, is a new mineral from Lengenbach quarry in the Binn Valley, Val... more Raberite, ideally Tl5Ag4As6SbS15, is a new mineral from Lengenbach quarry in the Binn Valley, Valais, Switzerland. It occurs very rarely as euhedral crystals up to 150 m m across associated with yellow needle-like smithite, realgar, hatchite and probable trechmannite, edenharterite, jentschite and two unidentified sulfosalts. Raberite is opaque with a metallic lustre and has a dark brown–red streak. It is brittle with a Vickers hardness (VHN10) of 52 kg mm–2 (range 50–55) corresponding to a Mohs hardness of 2½–3. In reflected light raberite is moderately bireflectant and very weakly pleochroic from light grey to a slightly greenish grey. It is very weakly anisotropic with greyish to light blue rotation tints between crossed polars. Internal reflections are absent. Reflectance percentages for the four COM wavelengths [listed as Rmin, Rmax, (λ)] are 30.6, 31.8 (471.1 nm), 28.1, 29.3 (548.3 nm), 27.1, 28.0 (586.6 nm), and 25.8, 26.9 (652.3 nm). Raberite is triclinic, space group P1, wi...
Tazzoliite, ideally Ba2CaSr0.5Na0.5Ti2Nb3SiO17[PO2(OH)2]0.5, is a new mineral (IMA 2011-018) from... more Tazzoliite, ideally Ba2CaSr0.5Na0.5Ti2Nb3SiO17[PO2(OH)2]0.5, is a new mineral (IMA 2011-018) from Monte delle Basse, Euganei Hills, Galzignano Terme, Padova, Italy. It occurs as lamellar pale orange crystals, which are typically a few m m thick and up to 0.4 mm long, closely associated with a diopsidic pyroxene and titanite. Tazzoliite is transparent. It has a white streak, a pearly lustre, is not fluorescent and has a hardness of 6 (Mohs' scale). The tenacity is brittle and the crystals have a perfect cleavage along {010}. The calculated density is 4.517 g cm–3. Tazzoliite is biaxial (–) with 2Vmeas of ~50º, it is not pleochroic and the average refractive index is 2.04. No twinning was observed. Electronmicroprobe analyses gave the following chemical formula: (Ba1.93Ca1.20Sr0.52Na0.25Fe0.102+)Σ4 (Nb2.88Ti2.05Ta0.07Zr0.01V0.015+)Σ5.02SiO17[(P0.13Si0.12S0.07)Σ0.32O0.66(OH)0.66][F0.09(OH)0.23]Σ0.32.Tazzoliite is orthorhombic, space group Fmmm, with unit-cell parameters a = 7.4116(...
ABSTRACT Synthesis of gold nanoclusters inside strongly acidic ion exchangers, in beaded forms, i... more ABSTRACT Synthesis of gold nanoclusters inside strongly acidic ion exchangers, in beaded forms, is carried out under different conditions. After metallation with [Au(en)2]Cl3 and reduction with H2 in the absence of any added aqueous phase, Au0/-SO3H nanocomposites are produced that are compared with Au0/-SO3− Na+ ones obtained with NaBH4 as reductant in aqueous medium. Reduction conditions allow control of both distribution and size of the metal nanoclusters. Metal distribution inside the polymer beads appears to be quite homogeneous under the hydrogen reduction conditions and metal nanoclusters size turns out to be size-controlled in the 3–5 nm range. In the case of the action of NaBH4 in water, metal distribution inside the polymer beads appears to be quite peripheral and the metal nanoclusters turn out to be size-controlled but definitely larger, 5–7 nm, than those obtained by action of molecular hydrogen.
This paper is a critical discussing key on previous results of the authors in the field of glassc... more This paper is a critical discussing key on previous results of the authors in the field of glassceramic scaffolds for tissue engineering. With the aim of developing biological substitutes that restore, maintain or improve tissue functionality, glass-ceramic scaffolds were produced starting from a glass system composition enriched with traces of specific elements. The presence of one or more specific ions can modulate the better environmental conditions to favour the growth of specific specialised cells, a necessary prerequisite to originate different kinds of tissues. The main predictable use is for bone reconstruction, but other possible uses are expectable for some specific tissues (cartilage, nerve, tendons, etc.). In order to obtain the best initial tissue integration, a decisive role is played by porosity of the glass scaffold. The glass structure can generally be resorbed, leaving its volume available for tissue nodules which grow and assemble together, producing an equal volume of tissue. In bone, the action is synergically increased thanks to the phenomena of bone conduction and bone induction of the proposed porous bioactive ceramics. On the other hand, glass-ceramic scaffolds have already been appreciated as a superior material for bone healing. Compared to similar hydroxyapatite structures, the glassceramic ones exhibit a greater starting mechanical resistance (useful for surgical manipulations) and differently from the hydroxyapatite ones, they are resorbed more easily in time. This is a good requisite for a material to be used in bone tissue engineering. The ceramic bioactive systems can be used both in bulk and as coatings.
characterized by pain and/ or stiffness of knee and/ or hip. They were included at the first visi... more characterized by pain and/ or stiffness of knee and/ or hip. They were included at the first visit or within 6 months of the first visit to the general practitioner for these symptoms. Study centers comprise ten general and university hospitals located in urbanized and semiurbanized regions in the Netherlands. A special program was developed to minimize loss to follow up, comprising newsletters, website and organizing symposia to present the results and progress of CHECK. An overview of measures that are included in the study can be found at our website www.check-research.com. Results: After 7 years a total of 105 (10%) participants had dropped out. Reasons included loss of interest (21%), comorbidity that complicated participating of CHECK too much (18%), death (12%), contact lost (11%), costs incurred for the study (5%), and other reasons (33%). Dropouts did not differ significantly from other participants in baseline characteristics. Over 7 years follow-up clinical characteristics including pain, stiffness and function of disease-specific (WOMAC) and the subscales of generic self-report questionnaire (SF36) on average did not change significantly, although at least half of the patients experienced radiographic progression. Scoring of 5-year follow up is complete: at this point, 50 % of the participants progressed by at least one Kellgren and Lawrence grade in the knee, and 25% in the hip. Preliminary analyses suggest the existence of several clinical and radiological phenotypes. Conclusions: CHECK is a valuable source of information of early symptomatic OA with a low loss to follow-up and a multidisciplinary approach that allows the collections of high-quality data on clinical, radiological and biochemical variables. DSPCC, diclofenac submicron particle containing capsules; TID, three times daily; BID, twice daily; SF-36, Medical Outcomes Survey Short Form 36 (SF-36), version 2. *P 0.03. Bold values represent scores ! minimally clinically important difference (!2.5 for physical component score; !5.0 for SF-36 domain scores). Data above presented as means however, all P-values are compared with placebo and calculated from least-squared mean changes from baseline.
Journal of Rheumatology; 35:1092-5. ISSN 0315-162X, 2008
Objective. Synovial fluid (SF) may contain a number of crystals that optical microscopy is unable... more Objective. Synovial fluid (SF) may contain a number of crystals that optical microscopy is unable to identify with certainty. Scanning electron microscopy (SEM) was utilized in this study to characterize SF crystals in the context of knee osteoarthritis (OA). Methods. SF was collected from the knees of 25 patients with OA and examined under optical light microscopy. Calcium pyrophosphate dihydrate (CPPD) crystals were assessed by means of compensated polarized light microscopy, while alizarin red S staining was performed to identify apatite (BCP) crystals. All the specimens were also analyzed by SEM and x-ray diffractometry, as gold standards. Results. CPPD crystals were found in 32% and BCP in 24% of the SF examined by SEM. The degree of concordance between polarized light microscopy and SEM was 0.83 for CPPD and 0.46 for BCP (kappa statistic). The secondary and backscatter electron SEM observations allowed identification of silicon dioxide (SiO 2) crystals in 8 out of 10 patients in whom polarized light microscopy revealed irregular and polymorph crystals. Conclusion. SiO 2 crystals cannot be readily identified by their morphology or polarization properties under optical microscopy. Their presence, nevertheless, did not lead to misclassification.
OBJECTIVE Synovial fluid (SF) may contain a number of crystals that optical microscopy is unable ... more OBJECTIVE Synovial fluid (SF) may contain a number of crystals that optical microscopy is unable to identify with certainty. Scanning electron microscopy (SEM) was utilized in this study to characterize SF crystals in the context of knee osteoarthritis (OA). METHODS SF was collected from the knees of 25 patients with OA and examined under optical light microscopy. Calcium pyrophosphate dihydrate (CPPD) crystals were assessed by means of compensated polarized light microscopy, while alizarin red S staining was performed to identify apatite (BCP) crystals. All the specimens were also analyzed by SEM and x-ray diffractometry, as gold standards. RESULTS CPPD crystals were found in 32% and BCP in 24% of the SF examined by SEM. The degree of concordance between polarized light microscopy and SEM was 0.83 for CPPD and 0.46 for BCP (kappa statistic). The secondary and backscatter electron SEM observations allowed identification of silicon dioxide (SiO2) crystals in 8 out of 10 patients in w...
The W (Mo, Sn, Bi) and Cu (Pb, Zn, Ag, Te, Co, Ni, etc.) deposits of Bedovina mark the closure of... more The W (Mo, Sn, Bi) and Cu (Pb, Zn, Ag, Te, Co, Ni, etc.) deposits of Bedovina mark the closure of the MiddleTriassic magmatic cycle of the Predazzo-Monzoni Eruptive Complex, composed of latiandesitic and latibasaltic lavas, monzonitic stocks with shoshonitic affinity, K-alkaline monzosyenitic bodies, and some granitic masses. The mineralization is hosted in a stockwork of veins which intersects the volcanics and, occasionally, granitoid masses, and rarely acidic and mafic veins. Two different metalliferous phases can be recognized, the first mainly wolfram-bearing, the second copper-polymetallic. The wolfram phase is represented by quartz+Kfeldspar+tourmaline veins, with scheelite, minor apatite and rutile, rare cassiterite, and hematite. Sporadic synchysite-(Ce) and molybdenite occur in granite breccias. The copper-polymetallic phase was superimposed to the wolfram one after a brittle tectonic event; it comprises quartz, chalcopyrite, minor pyrite, sphalerite, galena and traces of ...
<p>Seven granitoid rocks were selected due to the well-defined mineralogical content, the t... more <p>Seven granitoid rocks were selected due to the well-defined mineralogical content, the typical the holocrystalline texture, their absent (or very poor) Crystal Preferred Orientations (CPOs), and very-low porosity in order to apply a predictive approach that quantifies and simulates the rock thermal properties by considering the contributions of the mineral phases content. For this purpose, thermal properties of granodiorite, tonalite, granite, and gabbro rock samples were analysed and compared by <em>(i) </em>direct measurements on the bulk rock samples, <em>(ii)</em> by applying Quantitative Phase Analysis (QPA) on Digital Imaging Analysis (DIA) and Xray diffraction Rietveld method, and <em>(iii)</em> by 2D numerical modelling.</p><p>The results confirm the good accuracy of DIA-QPA method by the good according with data refined by X-Ray diffraction Rietveld method, and indicate the potential reliability of the more attractive approach in terms of prediction of the 2D modelling starting by the Quantitative Phase Analysis (QPA) based on Digital Imaging Analyses (DIA). This method, indeed, permits to observe concurrently different mineralogical and textural parameters (such as mineral abundance, grain size and grain size distribution), and it also provides a deep knowledge of the rock&#8217;s thermal behaviour.</p><p>Numerical modelling results indicate that a steady-state condition (SSC) is reached by the combination of thermal contribution given both in terms of modal mineral abundance (mainly controlled by mineralogical phase content related to the quartz occurrence) and in terms of rock texture (by the grain-size dimensions and the geometrical distribution of minerals), considering negligible the porosity.</p><p>The use of predictive models for the evaluation of the rocks thermal properties can find many important applications (e.g., in deep and shallow geothermal systems, as well as in building construction materials), and also permits to evaluate the expected energy performance of borehole heat exchange probes, involving granitoid lithologies, representing a suitable alternative also in cases where direct measures are not possible.</p>
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Papers by Luca Peruzzo