2,502 research outputs found
The App Save Yourself Improves Knowledge in Earth Environmental Emergency and Safe Behaviors
Saving Yourself is an App from the methodological experience of Learning on Gaming, which is a new teaching approach: to learn while playing, that is different from Edutainment, designed both to educate and entertain, and Gaming to Learn, which consists of playing a game without specific didactic to outcome knowledge. With Learning on Gaming the game “hides” didactic inside the game: this could improve learning processes and, at the same time, renew teaching competences of mentors. Our experience is based on the application of Learning on Gaming to Digital Game Based Learning, through a Computer Class Role Playing Game (CCRPG). Adventure pathways of these CCRPG are focused on Earth Sciences and are interdisciplinary, multilingual and they are a good example of innovative teaching. As a CCRPG spin-off, “Saving Yourselves” is an App for Educators, Trainers, Teachers, Students, to know the earthquakes and volcanoes and strategies to reduce the risks associated with these phenomena. The App is intended to provide the most immediate and useful way to behave in the event of a geological emergency, with particular reference to volcanology emergency and seismic emergency. It can be used at school to optimize security education measures, but it can also be a game that is useful to rethink what has been learned. Saving Yourself is for all ages, because there are versions of the activity for kindergarten, primary school and secondary school and it is multilingual. It takes advantage of Games, ICT (Information and Communication Technologies), Innovative Teaching, to activate digital, scientific and technical skills
Geoquest Project Implementation and Experimentation of a Computer Classroom Role Playing Game: Final Results
The GeoQuest Project started as a PhD research project in Teaching and Learning Processes in Science Education. It aims to answer to both students and teachers’ needs in an ever-changing world. Today, in particular, students need teaching tools that use different communication codes, as they are less accustomed to abstraction. An increasingly interconnected and technological world requires students to have specific skills: knowledge of the disciplines founding cores in an interdisciplinary key is required, along with technical and technological skills, mastery of foreign languages, flexibility, attitude to team working, creativity and entrepreneurship. Scientific subjects, such as Science, Technology, Engineering and Mathematics (STEM subjects) need to be strengthened and studied through a laboratory approach. On the other hand, teachers need user-friendly teaching tools, which allow and promote teamwork, which allow the laboratory teaching and the CLIL (Content and Language Integrated learning) approach. We have therefore developed a Computer Classroom Role Playing Game (CCRPG), GeoQuest, which has already been described in some international publications; a multi-phase experimentation was carried out for two years. In this paper, we illustrate the phases of experimentation, the excellent results achieved and the quantitative statistical analysis. The final outcome is how GeoQuest Project matches the students and teachers’ needs
SIMULATION OF ANTIHYDROGEN PRODUCTION IN AEGIS
L\u2019accelerazione gravitazionale dell\u2019antimateria prodotta da un corpo composto di materia non \ue8 mai stata misurata.
Dato che la Relativit\ue0 Generale di Einstein \ue8 stata concepita prima della scoperta dell\u2019antimateria nei raggi cosmici la validit\ue0 del Principio di Equivalenza Debole \ue8 messo in dubbio per l\u2019antimateria in un campo di materia.
Il principale obiettivo scientifico dell\u2019esperimento AEGIS al Cern \ue8 la prima misura dell\u2019accelerazione di gravit\ue0 dell\u2019anti-idrogeno con una precisione dell\u20191 per cento.
L\u2019esperimento \ue8 molto sfidante perch\ue9 questa misurazione richiede condizioni molto stringenti per poter creare un fascio di atomi di anti-idrogeno che possano essere diretti su una superficie per evidenziare il loro comportamento gravitazionale.
La presente Tesi simula il comportamento della parte principale dell\u2019esperimento, la produzione di anti-idrogeno, per verificare se la misurazione \ue8 fattibile e suggerire possibili modifiche per aumentare il numero di atomi di anti-idrogeno prodotti.
I risultati di questa tesi sono prodotti con un calcolo Montecarlo scritto in Fortran e C++, usando routine della libreria ODEINT per risolvere numericamente equazioni differenziali ordinarie. Il calcolo \ue8 basato su un trattamento semiclassico della reazione di scambio-carica che produce l\u2019anti-idrogeno, usando un Classical Trajectory Montecarlo (CTMC) in assenza e presenza del campo magnetico di 1T presente nella zona di produzione dell\u2019anti-idrogeno per confinare assialmente gli anti-protoni.
Il risultato di questa tesi \ue8 che l\u2019unico modo per produrre un numero sufficiente di atomi di anti-idrogeno per misurare la loro accelerazione gravitazionale \ue8 di utilizzare una targhetta di silicio verticale in trasmissione. La targhetta in riflessione della proposta inziale di AEGIS che \ue8 attualmente utilizzataThe gravitational acceleration of antimatter produced by a body made of matter has never been measured.
As Einstein General Relativity was conceived before the discovery of antimatter in cosmic rays the validity of the Weak Equivalence Principle is questioned for antimatter in a matter field.
The primary scientific goal of the AEGIS experiment at Cern is the first measurement of gravity acceleration of antihydrogen with a precision of 1 percent.
The experiment is very challenging because this measurement requires very stringent conditions to be able to create a beam of antihydrogen atoms which can be directed to a target to see its gravitational behavior.
The present Thesis simulates the behavior of the main part of the experiment, the production of antihydrogen, to check whether the measurement is feasible and suggest possible modifications to increase the number of antihydrogen atoms which are produced.
The results of the thesis are produced by a Montecarlo calculation written in Fortran 90 and C++, using routines of the ODEINT library for numerically solving ordinary differential equations. The calculation is based on a semiclassical treatment of the charge-exchange reaction that produces antihydrogen, using a Classical Trajectory Montecarlo (CTMC) with and without the magnetic field of 1T in the antihydrogen production area to axially confine anti-protons.
The result of the thesis is that the only way to produce a sufficient number of antihydrogen atoms to measure their gravitation acceleration is to use a vertical silicon transmission target. The reflection target of the initial AEGIS proposal which is now used in the experiment doesn\u2019t seem to be able to produce enough atoms for the measurement. Two different kinds of transmission targets are being tested at Cern
Intrarenal Resistance Index as a Prognostic Parameter in Patients with Liver Cirrhosis Compared with Other Hepatic Scoring Systems
Background and Aims: Patients with advanced liver cirrhosis who develop renal dysfunction have a poor prognosis. Elevated intrarenal resistance indices (RIs) due to renal vascular constriction have been described before in cirrhotic patients. In the current study, we prospectively investigated the course of intrarenal RIs and compared their prognostic impact with those of the Model for End-Stage Liver Disease (MELD) and the Child-Pugh scores. Methods: Sixty-three patients with liver cirrhosis underwent a baseline visit which included a sonographic examination and laboratory tests. Forty-four patients were prospectively monitored. The end points were death or survival at the day of the follow-up visit. Results: In 28 patients, a follow-up visit was performed after 22 8 months (group 1). Sixteen patients died during follow-up after 12 8 months (group 2). Group 2 patients showed a significantly higher baseline RI (0.76 +/- 0.05) than group 1 patients (RI = 0.72 +/- 0.06; p < 0.05). As shown by receiver operating characteristic analysis, the RI and the MELD score achieved similar sensitivity and specificity {[}area under the curve (AUC): 0.722; 95% confidence interval (95% CI): 0.575-0.873 vs. AUC: 0.724; 95% CI: 0.575-0.873, z = 0.029, n.s.] in predicting survival and were superior to the Child-Pugh score (AUC: 0.677; 96% Cl: 0.518-0.837). Conclusion: The RI is not inferior in sensitivity and specificity to the MELD score. Cirrhotic patients with elevated RIs have impaired short- and long-term survival. The RI may help identify high-risk patients that require special therapeutic care. Copyright (C) 2012 S. Karger AG, Base
Towards the formation of a positronium coherent beam
Positronium (Ps) has emerged as a promising test particle within the QUPLAS
collaboration for investigating the gravitational effect. In this work, we
present a novel approach to generate a monoenergetic and highly coherent Ps
beam by creating a negative Ps ion (Ps, consisting of two electrons and one
positron). The necessary positron beam is formed by using a high flux electron
LINAC. Subsequently, we utilize a Fabry-Perot IR laser cavity operating at a
wavelength of 1560 nm to selectively remove the extra electron. An alternative
pulsed laser operating at a 3600 nm wavelength was studied to reduce broadening
due to recoil and excitation. Here, we provide a Monte Carlo simulation to
estimate the characteristics of the Ps beam, including its energy distribution
and intensity profiles. The results obtained from this study will provide
essential groundwork for future advancements in fundamental studies as Ps
gravity measurements by using a Mach-Zehnder interferometer.Comment: 16 pages, 4 figure
A large-momentum-transfer matter-wave interferometer to measure the effect of gravity on positronium
This paper reports the study of a new interferometric configuration to measure the effect of gravity on positronium. A Mach–Zehnder matter-wave interferometer has been designed to operate with single-photon transitions and to transfer high momentum to a 200 eV positronium beam. The work shows the results and methods used to simulate the interferometer and estimate the
operating parameters and the time needed to perform the experiment. It has been estimated that within less than 1 year, the acquisition time is sufficient to achieve a 10% accuracy level in measuring positronium gravitational acceleration, even with a poorly collimated beam, which is significant for theoretical models describing matter–antimatter symmetry. These results pave the way for single photon transition large momentum transfer interferometry with fast atomic beams, which is particularly useful for studies with antimatter and unstable atoms
Kinematic bidimensional analysis of the propulsion technique in wheelchair rugby athletes
Wheelchair rugby is a sport ideated for individuals with cervical spinal cord injury (CSCI) which is extremely important for maintaining their neuromuscular abilities and improving their social and psychological wellbeing. However, due to the frequent changes in direction and speed it considerably stresses the players' upper limbs. 13 athletes have undergone two sports-related tests on an inertial drum bench and several kinematic parameters have been registered. Most athletes use a semi-circular pattern which is considered protective for the upper limb. With increasing speed, range of motion (ROM) increases. Release angles increment and contact angles reduce, displacing the push angle forward to increase speed. Instead, the more anterior late push angle used to increase velocity is a factor which further loads the shoulder joint. However, other factors affecting propulsion technique, such as posture and wheelchair set up should be studied to further reduce loading on the upper limb
SerpinB3 as hepatic marker of post-resective shear stress
Post-resective liver failure is a frequent complication of liver surgery and it is due to portal hyperperfusion of the remnant liver and to arterial vasoconstriction, as buffer response of the hepatic artery. In this context, splenectomy allows a reduction of portal flow and increases the survival chance in preclinical models. SerpinB3 is over-expressed in the liver in oxidative stress conditions, as a mechanism of cell defense to provide survival by apoptosis inhibition and cell proliferation. In this study, the expression of SerpinB3 was assessed as predictor of liver damage in in vivo models of major hepatic resection with or without splenectomy. Wistar male rats were divided into 4 groups: group A received 30% hepatic resection, group B > 60% resection, group C > 60% resection with splenectomy and group D sham-operated. Before and after surgery liver function tests, echo Doppler ultrasound and gene expression were assessed. Transaminase values and ammonium were significantly higher in groups that underwent major hepatic resection. Echo Doppler ultrasound showed the highest portal flow and resistance of the hepatic artery in the group with > 60% hepatectomy without splenectomy, while the association of splenectomy determined no increase in portal flow and hepatic artery resistance. Only the group of rats without splenectomy showed higher shear-stress conditions, reflected by higher levels of HO-1, Nox1 and of Serpinb3, the latter associated with an increase of IL-6. In conclusion, splenectomy controls inflammation and oxidative damage, preventing the expression of Serpinb3. Therefore, SerpinB3 can be considered as a marker of post-resective shear stress
Thick-film gas sensors based on vanadium-titanium oxide powders prepared by sol-gel synthesis
Two titania powders modified by 10 at.% of vanadium were prepared by two different sol-gel routes. The powders fired at 650 °C had the rutile structure. These powders were used to produce prototype thick-film sensors. Four series of thick-film samples were fabricated by screen-printing, fired for 1 h at 650 and 850 °C. The morphology and gas-sensing properties were examined and compared with those of pure and Ta-added titania films, previously studied by the authors. Ta addition inhibited the anatase-to-rutile phase transformation during heating and was also effective in keeping the TiO2 grain size in the nanometre range. On the contrary, V addition facilitated the anatase-to-rutile phase transformation. Thick films obtained from the two powders had similar conductance behaviour vs. temperature. The gas response of the films was affected by both the grain size and firing temperature. © 2003 Elsevier Ltd. All rights reserved
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