521 research outputs found
The Catania 1669 lava eruptive crisis: simulation of a new possible eruption
SCIARA (Smart Cellular Interactive Automata for modeling the Rheology of Aetnean lava flows,
to be read as “shea’rah”), our first two-dimensional Cellular Automata model for the simulation of
lava flows, was tested and validated with success on several lava events like the 1986/87 Etnean
eruption and the last phase of the 1991/93 Etnean one. Real and simulated events are satisfying
within limits to forecast the surface covered by the lava flow. Moreover, improved versions have
been adopted in testing other real lava flows of Mount Etna and of Reunion Island (Indian Ocean).
The model has been applied with success in the determination of risk zones in the inhabited
areas of Nicolosi, Pedara, S. Alfio and Zafferana (Sicily). The main goal of the present work has
been the verification of the effects, in volcanic risk terms, in the Etnean area from Nicolosi to
Catania, of a eruptive crisis similar to the event that occurred in 1669, as if the episode would
happen nowadays.
Catania has been severely interested in some major Etnean events in history, the most famous
one being, namely, the 1669 eruption, involving 1 km3 of lava during 130 days. The simulation of
lava tubes and the usage of different histories within the experiments have been crucial in the
determination of a new risk area for Catania. In fact, simulations carried out without the introduction
of lava tubes, never involved the city, proving the fact that lava tubes, played a fundamental role in
the 1669 Catania lava crisis
Development of doped-KMgF3 fluoro-perovskite nanoparticles with upconversion properties for potential biomedical application
Upconverting nanoparticles (UCNps) possess the ability to convert light from low to high energy. In particular, the absorption of radiation by these nanomaterials in the near-infrared region of the spectrum, and their subsequent emission in the visible region, is of great interest for biomedical applications. Conventional antitumor therapies often produce a high degree of side effects. Consequently, it is proposed to investigate the development of less invasive alternative therapies as photothermal therapy, using UCNps. The upconversion property could be achieved by incorporating dopants (rare earths and transition metals) in fluorine-based crystalline environments. On the other hand, it is important to control the size of the nanoparticles for their use in biomedical applications, for that reason we plan to obtain nanoparticles with an approximate size less than 50 nm. In the present work, the development of KMgF3 fluoroperovskite nanoparticles by solvothermal synthesis is presented, applying a factorial experimental design which consists of four factors (temperature, time and two limiting reagents) at two levels and choosing the average particle size as a variable response. The samples were characterized by powder X-ray diffraction and Transmission Electron Microscopy, in order to know the crystalline phase and particle size. As a result, KMgF3 nanoparticles with an average size between 13 and 31 nm were obtained. In addition, data obtained were statistically processed by Analysis of Variance, to determine the significant factors and their interactions, achieving the optimal synthesis conditions. From these results, a series of samples doped with Mn2+ and/or Nd3+ were obtained in order to find the optimal dopant concentrations for efficient upconversion properties. Our work is the starting point for the development of UCNps allowing them to be applied in future antitumor therapies.Agencia Nacional de investigación e InnovaciónPEDECIBAComisión Académica de Postgrad
Fluoro-perovskite nanomaterials for photodynamic cancer treatment”
Upconverting nanoparticles (UCNps) possess the ability to convert light from low to high energy. In particular, the absorption of radiation by these nanomaterials in the near-infrared region of the spectrum, and their subsequent emission in the visible region, is of great interest for biomedical applications. Conventional antitumor therapies often produce a high degree of side effects. Consequently, it is proposed to investigate the development of less invasive alternative therapies as photothermal therapy, using UCNps. The upconversion property could be achieved by incorporating dopants (rare earths and transition metals) in fluorine-based crystalline environments. On the other hand, it is important to control the size of the nanoparticles for their use in biomedical applications, for that reason we plan to obtain nanoparticles with an approximate size less than 50 nm. In the present work, the development of KMgF3 fluoroperovskite nanoparticles by solvothermal synthesis is presented, applying a factorial experimental design which consists of four factors (temperature, time and two limiting reagents) at two levels and choosing the average particle size as a variable response. The samples were characterized by powder X-ray diffraction and Transmission Electron Microscopy, in order to know the crystalline phase and particle size. As a result, KMgF3 nanoparticles with an average size between 13 and 31 nm were obtained. In addition, data obtained were statistically processed by Analysis of Variance, to determine the significant factors and their interactions, achieving the optimal synthesis conditions. From these results, a series of samples doped with Mn2+ and/or Nd3+ were obtained in order to find the optimal dopant concentrations for efficient upconversion properties. Our work is the starting point for the development of UCNps allowing them to be applied in future antitumor therapies.Agencia Nacional de investigación e InnovaciónPrograma de Desarrollo de las Ciencias BásicasComisión Académica de Postgrad
Targeted metabolomic profiling in rat tissues reveals sex differences
Sex differences affect several diseases and are organ-and parameter-specific. In humans and animals,
sex differences also influence the metabolism and homeostasis of amino acids and fatty acids, which
are linked to the onset of diseases. Thus, the use of targeted metabolite profiles in tissues represents
a powerful approach to examine the intermediary metabolism and evidence for any sex differences.
To clarify the sex-specific activities of liver, heart and kidney tissues, we used targeted metabolomics,
linear discriminant analysis (LDA), principal component analysis (PCA), cluster analysis and linear
correlation models to evaluate sex and organ-specific differences in amino acids, free carnitine and
acylcarnitine levels in male and female Sprague-Dawley rats. Several intra-sex differences affect
tissues, indicating that metabolite profiles in rat hearts, livers and kidneys are organ-dependent. Amino
acids and carnitine levels in rat hearts, livers and kidneys are affected by sex: male and female hearts
show the greatest sexual dimorphism, both qualitatively and quantitatively. Finally, multivariate
analysis confirmed the influence of sex on the metabolomics profiling. Our data demonstrate that
the metabolomics approach together with a multivariate approach can capture the dynamics of
physiological and pathological states, which are essential for explaining the basis of the sex differences
observed in physiological and pathological conditions
Predicting the impact of lava flows at Mount Etna (Italy)
Forecasting the time, nature and impact of future eruptions is difficult at volcanoes such as Mount Etna, in Italy, where eruptions occur from the summit and on the flanks, affecting areas distant from each other. Nonetheless, the identification and quantification of areas at risk from new eruptions is fundamental for mitigating potential human casualties and material damage. Here, we present new results from the application of a methodology to define flexible high-resolution lava invasion susceptibility maps based on a reliable computational model for simulating lava flows at Etna and on a validation procedure for assessing the correctness of susceptibility mapping in the study area. Furthermore, specific scenarios can be extracted at any time from the simulation database, for land-use and civil defence planning in the long-term, to quantify, in real-time, the impact of an imminent eruption, and to assess the efficiency of protective measures
Age as a risk factor in the occurrence of pneumothorax after transthoracic fine needle biopsy: Our experience
Transthoracic needle biopsy (TTNB) of the lung is a well-established technique for diagnosing many thoracic lesions, and is an important alternative to more invasive surgical procedures. Complications of TTNB include pneumothorax, hemoptysis, hemothorax, infection, and air embolism, with the most common complication as pneumothorax. From June 2011 to June 2014 we performed a prospective study of 188 patients who underwent TTNB with CT guidance at University Hospital of Salerno, Italy. Pneumothorax occurred in 14 of 188 biopsies (7.45%). With the respect of age of patients pneumothorax occurred more frequently in patients aged 60-70 years, while it was less frequent in younger (70 years). In conclusion, data of our prospective study documented that CT-guided TTNB is a safe and reliable procedure in elderly patients with suspected chest malignancy and is well tolerated
A petro-chemical study of ancient mortars from the archaeological site of Kyme (Turkey)
Fourteen samples of ancient mortars (joint mortars and plasters) from the archaeological
site of Kyme (Turkey) were studied by optical microscopy (OM), X-ray fluorescence (XRF),
X-ray powder diffraction (XRPD), scanning electron microscopy (SEM-EDS) and micro-
Raman spectroscopy to obtain information about their composition.The study allowed us to
identify a new type of plaster inside the archaeological site of Kyme, not detected by previous
studies of this site, in which vegetable fibers were intentionally added to the mixture. The
combination of a petrographic analysis on thin sections by polarized light microscopy
with a chemical analysis, has allowed us to highlight similarities and differences between
the mortars and to get information about the evolution of constructive techniques in the
archaeological area
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