260 research outputs found
Sustainable Phenolic Fractions as Basis for Furfuryl Alcohol-Based Co-Polymers and Their Use as Wood Adhesives
An analysis of the first-arrival times picked on the DSS and wide-angle seismic section recorded in Italy since 1968
We performed an analysis of refraction data recorded in Italy since 1968 in the frame of the numerous deep seismic
sounding and wide-angle reflection/refraction projects. The aims of this study are to construct a parametric
database including the recording geometric information relative to each profile, the phase pickings and the results
of some kinematic analyses performed on the data, and to define a reference 1D velocity model for the Italian
territory from all the available refraction data. As concerns the first goal, for each seismic section we picked
the P-wave first-arrival-times, evaluated the uncertainties of the arrival-times pickings and determined from each
travel time-offset curve the 1D velocity model. The study was performed on 419 seismic sections. Picking was
carried out manually by an algorithm which includes the computation of three picking functions and the picking-
error estimation. For each of the travel time-offset curves a 1D velocity model has been calculated. Actually,
the 1D velocity-depth functions were estimated in three different ways which assume: a constant velocitygradient
model, a varying velocity-gradient model and a layered model. As regards the second objective of this
work, a mean 1D velocity model for the Italian crust was defined and compared with those used for earthquake
hypocentre locations and seismic tomographic studies by different institutions operating in the Italian area, to
assess the significance of the model obtained. This model can be used in future works as input for a next joint
tomographic inversion of active and passive seismic data
Natural tannin-based rigid foams as insulation for doors and wall panels
Tannin-based rigid foams were shown to be good thermal insulating materials for use in the cavity of hollow-core wooden doors and other wooden cavities. Their thermal insulation capacity is comparable to that of totally synthetic, oil-derived foams, such as polyurethanes, but with the advantage that they do not burn and thus do not emit toxic gases on burning. Exposure to the weather of wooden hollow core structures filled with tannin-based foams confirm that the wood in contact with the foam is not affected by the acidity of the foam due to the already previously demonstrated incorporation of the acid hardener used by coreaction with the hardened polymer network
Enhancing mechanical and surface properties of eucalyptus wood
Eucalyptus is one of the most fast-growing trees. Therefore, in the last decades it has been extensively planted and harvested so that nowadays Eucalyptus is one of the most popular trees of the planet. There are many genres of this plant and they are often treated as a large bunch of the same timber characterized by moderate mechanical and surface properties which hinder their usage for any sight application (e.g. flooring, cladding, ceiling). In this study four species of Eucalyptus: E. grandis, E. dunnii, E. cloeziana and E. tereticornis were undergone to densification through hydro-thermo-mechanical treatment (HTM) first and then to oil heat-treatment (OHT) in order to improve their mechanical properties and hydrophobicity. It was observed that low density species (E. grandis) reaches higher compression degrees while heavier species (E. tereticornis) reach densities over 800 kg/m³; however, HTM decrease the variability of the properties. Treatments at higher temperature (160 °C) involves higher compression degree, lower set-recovery and higher surface hydrophobization, but also weaker mechanical properties. The hot oil post- treatment helps to contain the springback effect and to reduce the wettability of each specimen. Densified samples present similar surface hardness. The tailored application of the two treatments improves the properties of every Eucalyptus which can gain market also for nobler end-usages
The 9p21 Rs 1333040 polymorphism is associated with coronary microvascular obstruction in ST-segment elevation myocardial infarction treated by primary angioplasty
Background: Microvascular obstruction (MVO) after primary percutaneous coronary intervention (pPCI) leads to higher incidence of both early and late complications. A number of single nucleotide polymorphisms in 9p21 chromosome have been shown to affect angiogenesis in response to ischaemia. In particular, Rs1333040 with its three genotypic vriants C/C, T/C and T/T might influence the occurrence of MVO after pPCI. Methods: We enrolled ST-elevation myocardial infarction (STEMI) patients undergoing pPCI. The Rs1333040 polymorphism was evaluated by polymerase chain reaction-restriction fragment length polymorphism using restriction endonucleases (Bsml). Two expert operators unaware of the patients' identity performed the angiographic analysis; collaterals were assessed applying Rentrop's classification. Angiographic MVO was defined as a post-pPCI Thrombolysis In Myocardial Infarction (TIMI)<3 or TIMI 3 with myocardial blush grade 0 or 1, whereas electrocardiographic MVO was defined as ST segment resolution Results: Among our 133 STEMI patients (mean age 63 +/- 11 years, men 72%), 35 (26%) and 53 (40%) respectively experienced angiographic or electrocardiographic MVO. Angiographic and electrocardiographic MVO were different among the three variants (p= 0.03 and p=0.02 respectively). In particular, T/T genotype was associated with a higher incidence of both angiographic and electrocardiographic MVO compared with C/C genotype (p=0.04 and p=0.03 respectively). Moreover, Rentrop score <2 detection rate differed among the three genotypes (p=0.03). In particular T/T genotype was associated with a higher incidence of a Rentrop score <2 as compared with C/C genotype (p= 0.02). Conclusion: Rs1333040 polymorphism genetic variants portend different MVO incidence. In particular, T/T genotype is related to angiographic and electrocardiographic MVO and to worse collaterals towards the culprit artery
Cardiac cycle efficiency as prognostic index in ICUs
We implement a beam steering system based on a directly-modulated unseeded R-SOA, allowing the distribution of 2.4 GHz 64QAM OFDMA signals with 2048-subcarriers satisfying IEEE 802.16e specifications
Pulmonary Embolism in COVID-19 Patients: Which Diagnostic Algorithm Should We Use?
Introduction: Although pulmonary embolism (PE) is a frequent complication of the clinical course of COVID-19, there is a lack of explicit indications regarding the best algorithm for diagnosing PE in these patients. In particular, it is not clear how to identify subjects who should undergo computed tomography pulmonary angiography (CTPA), rather than simply X-ray and/or high resolution computed tomography (HRCT) of the chest. Methods: We retrospectively analyzed COVID-19 patients who presented to the Emergency Department (ED) of our University hospital with acute respiratory failure, or that developed acute respiratory failure during hospital stay, to determine how many of them had a theoretical indication to undergo CTPA for suspected PE according to current guidelines. Next, we looked for differences between patients who underwent CTPA and those who only underwent X-ray and/or HRCT of the chest. Finally, we determined whether patients with a confirmed diagnosis of PE had specific characteristics that made them different from those with a CTPA negative for PE. Results: Out of 93 subjects with COVID-19 and acute respiratory failure, 73 (78.4%) had an indication to undergo CTPA according to the revised Geneva and Wells scores and the PERC rule-out criteria, and 54 (58%) according to the YEARS algorithm. However, in contrast with these indications, only 28 patients (30.1%) underwent CTPA. Of note, they were not clinically different from those who underwent X-ray and/or HRCT of the chest. Among the 28 subjects who underwent CTPA, there were 10 cases of PE (35.7%). They were not clinically different from those with CTPA negative for PE. Conclusions: COVID-19 patients with acute respiratory failure undergo CTPA, X-ray of the chest, or HRCT without an established criterion. Nonetheless, when CTPA is performed, the diagnosis of PE is anything but rare. Validated tools for identifying COVID-19 patients who require CTPA for suspected PE are urgently needed
Floristic and coenological data from the travertine substrates of the SAC “Travertini Acque Albule (Bagni di Tivoli)” (Lazio Region – Central Italy)
During a phytosociological field-work campaign on the vegetation of the travertine outcrops, included in the Special Area of Conservation (SAC) “Travertini Acque Albule (Bagni di Tivoli)” (Central Italy), several taxa of particular interest were identified. Carex vulpina, Lolium apenninum, Onosma echioides subsp. angustifolia, Typha domingensis, T. laxmannii and Vicia pannonica subsp. pannonica are new for the Lazio administrative Region, while Ophrys illyrica and Zannichellia peltata are confirmed for the flora of this Region. For each of these taxa phytosociological samples describing the plant communities in which they were found are provided. New records for rare species were also reported for cryptogams such as Algae, Lichens and Mosses
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