First Occurrence of Willhendersonite in the Lessini Mounts, Northern Italy

none2noWillhendersonite is a rare zeolite, with very few occurrences reported globally (Terni Province, Italy; the Eifel Region, Germany; Styria, Austria). Moreover, the data available from these sites are very limited and do not allow a detailed picture of this zeolite’s mineralogical and chemical characteristics. In this work, a new willhendersonite occurrence is reported from the Tertiary volcanic rocks of the Lessini Mounts, northern Italy. Morphology, mineralogy and chemical composition of selected crystals were studied by scanning electron microscopy (SEM), energy-dispersive X-ray (EDX), X-ray Diffraction (XRD), and electron probe microanalyser (EPMA). Willhendersonite occurs within basanitic rocks as isolated, colorless, transparent crystals with prismatic to flattened morphologies. Individual crystals often grow together to form small elongated clusters and trellis-like aggregates. The diffraction pattern exhibits 33 well-resolved diffraction peaks, all of which can be indexed to a triclinic cell with unit cell parameters a = 9.239(2) Å; b = 9.221(2) Å; and c = 9.496(2) Å, α = 92.324(2)◦, β = 92.677(2)◦, γ = 89.992◦ (Space Group P1). The chemical data point to significant variability from Ca-rich willhendersonite (K0.23Na0.03 )Σ=0,26Ca1.24 (Si3.06Al3,00Fe3+0.01)Σ=6,07 O12·5H2O) to Ca-K terms (K0.94Na0.01)Σ=0,95Ca0.99 (Si3.07Al2.93Fe3+0.00)Σ=6,00O12·5H2O). Willhendersonite from the Lessini Mounts highlights the existence of an isomorphous series between the Ca-pure crystals and Ca-K compositions, possibly extended up to a potassic end-member.openMattioli, Michele; Cenni, MarcoMattioli, Michele; Cenni, Marc

optimisation of industrial parts by mesh morphing enabled automatic shape sculpting

n/

Status and change of tree crown condition at the CONECOFOR plots, 1996 - 2005

Between 1996 and 2005 crown condition at Italian Level II plots was assessed annually within the CONECOFOR programme. Three different assessment forms and manuals were adopted over this period of time (the first in 1996-97, the second between 1998 and 2004, the last starting in 2005); as a result, many of the parameters investigated and the data collected are neither homogeneous nor comparable over time. Since, however, neither the definition nor the assessment criteria for transparency changed, this parameter was chosen to represent crown condition variations over time. (In this survey, transparency is used as a proxy for defoliation.) Yearly field surveys were always preceded by an inter-calibration course, and were followed up by Quality Control surveys done by one or more Reference Teams. After 10 years, the results suggest that statistically significant variations in transparency, from one year to the next, are only scattered and display no recognizable trend. Overall, there were 15 variations, of which 7 were positive (i.e. increase in transparency), and 8 negative (i.e. decrease in transparency). The majority of variations is concentrated in the 1997-98 period. Significant defoliation trends were identified in 11 out of the 27 considered plots. In 4 cases these trends were positive (increased transparency)

Crack Propagation Analysis of Near-Surface Defects with Radial Basis Functions Mesh Morphing

Abstract Fracture mechanics analysis is nowadays adopted in several industrial fields to assess the capability of components to withstand fatigue loads. Finite Element Method (FEM) is a well-established tool for the evaluation of flaw Stress Intensity Factors (SIF) and for the survey of its propagation. Nevertheless the study of the growth of near-surface circular and elliptical cracks is still an arduous task to be faced with FEM. In fact, the interaction of the flaw with free surfaces leads the crack front to assume complex shapes, whose simulation cannot be easily accomplished. A possible answer to deal with such a problem is to use the mesh morphing technique, a nodal relocation methodology, that allows to cover different problems. In fact, with mesh morphing, it is possible to fit the baseline flaw front with the desired shape (generic shape) and to automatically simulate its evolution at a certain number of cycles. In the proposed work this approach is demonstrated exploiting ANSYS Mechanical as FEM tool and RBF Morph ACT Extension as mesh-morpher. The results of the proposed workflow are compared with those available in literature

Lumbar spinal canal stenosis: An early sign of amyloid transthyretin related amyloidosis

n/

A highly endemic area of Echinococcus multilocularis identified through a comparative re-assessment of prevalence in the red fox (Vulpes vulpes), Alto Adige (Italy: 2019-2020)

Surveillance of Echinococcus multilocularis at the edge of its range is hindered by fragmented distributional patterns and low prevalence in definitive hosts. Thus, tests with adequate levels of sensitivity are especially important for discriminating between infected and non-infected areas. In this study we reassessed the prevalence of E. multilocularis at the southern border of its distribution in Province of Bolzano (Alto Adige, northeastern Alps, Italy), to improve surveillance in wildlife and provide more accurate estimates of exposure risk. We compared the diagnostic test currently implemented for surveillance based on coproscopy and multiplex PCR (CMPCR) to a real-time quantitative PCR (qPCR) in 235 fox faeces collected in 2019 and 2020. The performances of the two tests were estimated using a scraping technique (SFCT) applied to the small intestines of a subsample (n = 123) of the same foxes as the reference standard. True prevalence was calculated and the sample size required by each faecal test for the detection of the parasite was then estimated. True prevalence of E. multilocularis in foxes (14.3%) was markedly higher than reported in the last decade, which was never more than 5% from 2012 to 2018 in the same area. In addition, qPCR showed a much higher sensitivity (83%) compared to CMPCR (21%) and agreement with the reference standard was far higher for qPCR (0.816) than CMPCR (0.298) meaning that for the latter protocol, a smaller sample size would be required to detect the disease. Alto Adige should be considered a highly endemic area. Routine surveillance on definitive hosts at the edges of the E. multilocularis distribution should be applied to smaller geographic areas, and rapid, sensitive diagnostic tools using directly host faeces, such as qPCR, should be adopted

Mineralogical dataset of natural zeolites from Lessini Mounts, Northern Italy: Analcime, natrolite, phillipsite and harmotome chemical composition

This dataset article contains mineralogical and chemical data of some natural zeolites such as analcime, natro- lite, phillipsite and harmotome. These minerals were found as secondary phases within vesicles and veins in the basaltic rocks of the Lessini Mounts, Northern Italy. Meth- ods for obtaining the datasets include optical microscopy, X-ray diffraction, scanning electron microscopy and elec- tron probe microanalysis. Analcime forms well-developed, transparent to milky crystals with a typical icositetrahe- dron habit. The average composition of analcime is calcu- lated as Na 13.79 Ca 0.01 K 0.03 Ba 0.03 [Al 14.28 Si 33.82 O 96 ] 16H 2 O, with all of the extra-framework sites occupied by sodium. Na- trolite usually forms hemispherical aggregates with glassy, colourless to white thin prismatic crystals, which generally radiate from a central point. The average chemical compo- sition of natrolite is Na 14.28 Ca 0.14 K 0.01 [Al 15.60 Si 24.59 O 80 ] 16H 2 O. Crystals of phillipsite-harmotome serie occur in a variety of forms and display a highly variable chemical composi- tion, from almost pure compositions to intermediate values. Phillipsite is more common and its average chemical com- position is Ca 1.40 Na 0.29 K 1.08 Ba 0.27 [Al 4.68 Si 11.28 O 32 ] 12H 2 O, while harmotome is rare and has an average chemical composition of Ca 0.97 Na 0.20 K 0.36 Ba 0.91 [Al 4.60 Si 11.46 O 32 ] 12H 2 O. The obtained dataset can be used for various purposes: it can be used by other authors to compare morphological features and chem- ical compositions of similar zeolites crystals discovered in other parts of the world, it can be compared with those ob- tained from similar geologic environments encouraging stud- ies on hydrothermal processes, and it could represent the starting point for a potential exploration of zeolites from an industrial point of view

Secondary mineral assemblages as indicators of multistage alteration processes in basaltic lava flows: evidence from the Lessini Mountains, Veneto Volcanic Province, Northern Italy

The secondary mineral assemblages in the Tertiary basalts from the Lessini Mountains are mainly clay minerals and zeolites, and result from multistage alteration processes. In the earliest Stage I, clay and silica minerals precipitate along the inner walls of the vesicles, followed by the deposition of the fine-grained zeolites of the Stage II (erionite, offretite, analcime, natrolite, heulandite and stilbite). The final Stage III is marked by a new generation of large, well-shaped zeolites (phillipstite-harmotomo, gmelinite, chabazite, willhendersonite and yugawaralite), followed by extensive crystallization of calcite. New morphological and chemical data are presented herein in order to reveal the chemical compositions of Lessini zeolite species, which have never been analyzed before. Textural and chemical observations indicate that the chemical elements for Stage I and II alteration minerals derived from the alteration of the basaltic glass and the primary phases in the volcanic host rocks. The final mineral assemblages of the Stage III suggest a variation in the crystallization conditions, probably related to the presence of new, late-stage fluids enriched in Ca and (CO3)2-, leached from the surrounding calcareous rocks

Mesh morphing and fatigue analysis integration: A way to increase the industrial productivity and performance with shape optimization

A methodology is developed for fatigue driven shape optimization of industrial mechanical components by means of mesh morphing. The methodology is integrated in commercial software platforms to increase its productivity and performance in industrial applications. It is well known that shape optimization is a way to improve the structural performance of components, yet it is mostly applied to linear elastic load cases. The idea of including fatigue analysis into the optimization process is of great interest for mechanical components design. Tools based on parametric geometries are becoming standard for fine-tuning optimization processes in industry. These tools can handle multiaxial fatigue analysis, but they are limited by difficulties in maintaining geometry coherence. The use of finite element models in place of parametric geometries results in a faster and more flexible methodology. In fact, mesh morphing avoids geometry coherence problems and the need of re-meshing. The aim of this work is the integration of mesh morphing and multiaxial fatigue in the context of shape optimization. A tool for achieving this was created and is presented here together with its application to part of a cast iron component subject to multi-axial high-cycle fatigue. The results obtained with the proposed methodology are closer to the industrial needs than those that can be obtained from shape optimization based on structure stiffness alone