309 research outputs found
Solid Lipid Nanoparticles: Technological Developments and in Vivo Techniques to Evaluate Their Interaction with the Skin
This chapter provides informations about the non-invasive
bioengineering techniques to study the SLN distribution and interaction on the ski
Zircon U-PB and LU-HF isotopic data from some peri-gondwana variscan terranes (Sardinia-Corsica block and calabropeloritan arc): new insights on the cenozoic geodynamic evolution of the central mediterranean basin
The reconstruction of pre-Variscan plates configuration in the Mediterranean area, is still poorly understood. Different hypotheses have been proposed to explain the relationships between peri-Tyrrhenian blocks such as Sardinia-Corse block (SCB) and Calabrian-Peloritain Arc (CPA), which before the opening of South Tyrrhenian Basin belonged to a branch of Southern Variscan Realm (Alvarez & Shimabukuro, 2009). Is still ambiguous if the CPA in the early time was formed by an amalgamation of two or more continental terranes that collided during Tertiary (Bonardi etal., 1980; Scandone, 1982) or was a single terrane during the middle and late Tertiary (Amodio-Morelli et al., 1976).
With the aim to provide a contribution in unraveling the peri-Tyrrhenian area evolution of the peri-Gondwana terranes, amalgamated during Variscan and widespread during Cainozoic opening (and closing) of Tethys, both Variscan and Tertiary rocks cropping out in the two Blocks have been
investigated, either magmatic or sedimentary. The first part of the research was focused on the magmatic bodies supposed belonging to the European Variscides with the aim to provide more constrains to the Variscan magmatic evolutionand so to draft the analogies between the present-day, separated blocks. In detail, the geochemical
data from magmatic and detrital zircons of the basement rocks highlight analogies or differences between the tectono-sedimentary sectors of the Sardinian Variscides (nappe and foreland zones) and between them and the Calabria Variscides. The geochemical whole rocks analyses and U-Pb data obtained show that the Variscan basement which crops out in the Northern part of the CPA
(Sila region) is characterized by the similar features of that in the SCB: the Middle Ordovician and Late Palaeozoic magmatic products recognized in the two blocks look similar. Some of these data can provide new insights also about the Ordovician evolution of the Northern Gondwana margin. To compare the and better constrain the relationships between the two blocks, detrital zircons
were sampled in Tertiary rocks in NE Sardinia, E Corsica and Calabria, commonly regarded as closely related to the tectonic evolution of the Central-western Mediterranean. The analyses performed suggest some differences on the classical paleo-geographic positions of the SCB respect
to the CPA and some assumptions can be made also about their relationships with other peri-Gondwana terranes. The association of U-Pb and Lu-Hf study performed on Tertiary detrital zircon populations is a good tool to furnish more data for recognize the pre-Variscan inputs suffered by the
peri-Tyrrhenian area, and to highlight differences and similarities between them. The first consideration that can be made is that the two blocks suffered different crustal
evolution. The main difference between them has given by the Grenvillian zircons input studied in the Tertiary deposits. The Southern part of CPA (Aspromonte and Peloritani) is characterized by the lacking of Mesoproterozoic age, whereas the Northern part of CPA (Sila) together with the SCB, are characterized by an important Grenvillian input. These considerations have a geodynamic implications about the misunderstood early evolution of the studied zones The Southern part of
CPA shows strong similarities with Cadomiam terranes, which permit to correlate it with the evolution of Variscides now cropping out in North Africa. The SCB and the Northern part of CPA could be associated to the other European Variscan terranes (e.g. Iberia) characterized by widespread Grenvillian zircons. A supplementary assumption that stem out from these analyses is that the early position of SCB and Northern part of CPA, were possibly close to the Amazonian craton or nearness to the West African craton (Arabian-Nubian shield and the Sahara Metacraton),
quite different from more of the proposed reconstructions.
Finally, considering all these data in the complicated evolution of southern Tyrrhenian basin, here is supported the “two-terrane model” (slightly different from that proposed by Alvarez and Shimabukuro, 2009) which considers the CPA composed by a northern CPA terrane connected with
the SCB from the end of the Variscan orogeny until the almost the Eocene. The southern CPA terrane suffered a different evolution before the opening of the Tyrrhenian Sea. According to the roll-back model of the westward subduction of Adria plate under Europe during Neogene-Pliocene the whole CPA, likely amalgamated in the early Miocene, was then tear apart from SCB and drifted
away eastwards during the open of the South Tyrrhenian basin
Ultrasound and 3D Skin Imaging: Methods to Evaluate Efficacy of Striae Distensae Treatment
Background. Over time, the striae rubra develop into striae alba that appear white, flat, and depressed. It is very important to determine the optimum striae management. In order to evaluate the effectiveness of these therapies, objective measurement tools are necessary. Objective. The aim of this study is to evaluate if ultrasonography and PRIMOS can be used to obtain an objective assessment of stretch marks type and stage; furthermore, we aim to apply these techniques to evaluate the efficacy of a topical treatment. Methods. 20 volunteers were enrolled with a two-month study. A marketed cosmetic product was used as the active over one body area. The controlateral area with stretch marks was treated with a “placebo” formulation without active, as a control. The instrumental evaluation was carried out at the beginning of the trial (baseline values or t0), after 1 month (t1), and at the end of the study (t2). Results. PRIMOS was able to measure and document striae distensae maturation; furthermore, ultrasound imaging permitted to visualize and diagnose the striae. Statistical analysis of skin roughness demonstrated a statistically significant reduction of Rp value only in a treated group. In fact, the Rp value represented a maximum peak height in the area selected. These results demonstrated that after two months of treatment only the striae rubra can be treated successfully. Conclusions. This work demonstrated that the 22MHz ultrasound can diagnose stretch marks; PRIMOS device can detect and measure striae distensae type and maturation. Furthermore, the high-frequency ultrasound and the 3D image device, described in this work, can be successfully employed in order to evaluate the efficacy of a topical treatment
3D CFD Transient Analysis of the Forces Acting on the Spool of a Directional Valve
Abstract In this paper, a study of a hydraulic directional valve using a tridimensional fluid-dynamic approach will be shown. During the valve spool displacement, the fluid-dynamics inside the valve creates forces who could reduce the valve performance. The adopted methodology allowed the valve designer to study the complex fluid-dynamic behavior inside the valve and greatly help them to design the internal geometry with the objective of improving the valve performance. This paper shows how a tridimensional fluid-dynamic approach can help engineers to develop the best valve geometry reducing the prototyping requirement and finally the time-to-market and, consequently, the development cost
Boron-loaded liposomes in the treatment of hepatic metastases: preliminary investigation by autoradiography analysis.
Boronophenylalanine (BPA)-loaded conventional and stabilized liposomes were prepared by the reversed phase evaporation method to treat liver metastases by boron neutron capture therapy. Conventional vesicles were composed of phosphatidylcholine and cholesterol, molar ratio 1:1. To obtain stealth liposomes, GM1 or PEG were included in the lipidic bilayer at a concentration of 6.67 or 5 mol%, respectively. Large unilamellar vesicles were formulated encapsulating BPA in the liposome aqueous compartment as a complex with fructose; BPA free base also was embedded into the lipidic bilayer. In vivo experiments were carried out after intravenous injection of liposome suspensions in BD-IX strain rats in which liver metastases had been induced. Alpha particle spectroscopy associated with histological analysis was performed to visualize boron spatial distribution in liver. Simultaneously, tissue boron concentrations were determined using inductively coupled plasma-mass spectroscopy. Results showed that PEG-modified liposomes accumulated boron in therapeutic concentrations (30 micrograms boron/g tissue) in metastatic tissue. The PEG-liposomes could be further explored in enhancing boron delivery to tumor cells
Projections of leaf turgor loss point shifts under future climate change scenarios
Predicting the consequences of climate change is of utmost importance to mitigate impacts on vulnerable ecosystems; plant hydraulic traits are particularly useful proxies for predicting functional disruptions potentially occurring in the near future. This study assessed the current and future regional patterns of leaf water potential at turgor loss point (Ψtlp) by measuring and projecting the Ψtlp of 166 vascular plant species (159 angiosperms and 7 gymnosperms) across a large climatic range spanning from alpine to Mediterranean areas in NE Italy. For angiosperms, random forest models predicted a consistent shift toward more negative values in low-elevation areas, while for gymnosperms the pattern was more variable, particularly in the alpine sector (i.e., Alps and Prealps). Simulations were also developed to evaluate the number of threatened species under two Ψtlp plasticity scenarios (low vs high plasticity), and it was found that in the worst-case scenario approximately 72% of the angiosperm species and 68% of gymnosperms within a location were at risk to exceed their physiological plasticity. The different responses to climate change by specific clades might produce reassembly in natural communities, undermining the resilience of natural ecosystems to climate change
Food Habits and Sport Practice According to BMI Categories and Rural/Urban Origin
The juvenile obesity is correlated to dietary and physical activity. Moreover, the rural or urban context could affect other aspects like time available to practice sport or the availability of sport facilities. Thus, this brief report investigated the relationship be- tween origin and food habits in children belonging to different BMI categories. Over than 1400 primary school students were interviewed with their parents about their food habits. All answers were stratified according to origin (rural/urban) and to BMI categories as defined in literature. The percentage of normal weight, overweight and obese children between rural and urban context were similar (p > 0.05). All the BMI categories were familiar to have breakfast and no differences were found between rural or urban context (p > 0.52). Over 70% of children had the principal meal in at least 15 minutes. In particular, all of them used to watch TV during this moment: no differences were found between urban/rural or BMI categories (p = 0.87 and p = 0.98). In general, most of urban children performed physical activity less than seven hours/week, while normal weight subjects were more active than obese one (p = 0.04). We concluded that school promotion and municipalities/institutions interven- tion could be a good solution to reach all children in environment where the amount of facilities is often poor
Projections of leaf turgor loss point shifts under future climate change scenarios
Predicting the consequences of climate change is of utmost importance to mitigate impacts on vulnerable ecosystems; plant hydraulic traits are particularly useful proxies for predicting functional disruptions potentially occurring in the near future. This study assessed the current and future regional patterns of leaf water potential at turgor loss point (Ψtlp) by measuring and projecting the Ψtlp of 166 vascular plant species (159 angiosperms and 7 gymnosperms) across a large climatic range spanning from alpine to Mediterranean areas in NE Italy. For angiosperms, random forest models predicted a consistent shift toward more negative values in low-elevation areas, whereas for gymnosperms the pattern was more variable, particularly in the alpine sector (i.e., Alps and Prealps). Simulations were also developed to evaluate the number of threatened species under two Ψtlp plasticity scenarios (low vs. high plasticity), and it was found that in the worst-case scenario approximately 72% of the angiosperm species and 68% of gymnosperms within a location were at risk to exceed their physiological plasticity. The different responses to climate change by specific clades might produce reassembly in natural communities, undermining the resilience of natural ecosystems to climate change
- …