Possible strategies to enhance students' learning and achievement in mathematical modelling teaching experiences

In the present work preliminary results about strategies to enhance students' learning and achievement in mathematical modelling teaching experiences are presented. The results confirm the importance of employing real world problems which are perceived as important by students. Moreover, they also suggest that the design of teaching experiences in which the initial steps of the modelling cycle can be carried out with a few or even any mathematical language could enhance students' perception of self-efficacy, thus providing a motivational push also for the subsequent steps, where specific disciplinary language must be employed. Finally, also the use of ICT and mathematical tools which are perceived by the students as belonging to the university and employment world can increase students' perception of value

Shared drawings in a mathematical modelling activity: An exploratory study

Recently, scholars have argued that drawings have a crucial role in the students’ modelling performance. Nevertheless, such a correlation cannot be extended to complex modelling problems. In this work, we consider the students’ drawing activities when dealing with a complex geometry problem. In particular, this paper reports an exploratory study from 11-grade students exposed to a realistic scenario from the sport context on which they have worked for 4 hours. The analysed data, which focus on one of the class discussions, show that drawings help students in going throughout the modelling process and that even shared inaccurate drawings play a crucial role in this sense

Possible strategies to enhance students’ learning and achievement in mathematical modelling teaching experiences

In the present work preliminary results about strategies to enhance students’ learning and achievement in mathematical modelling teaching experiences are presented. The results confirm the importance of employing real world problems which are perceived as important by students. Moreover, they also suggest that the design of teaching experiences in which the initial steps of the modelling cycle can be carried out with a few or even any mathematical language could enhance students’ perception of self-efficacy, thus providing a motivational push also for the subsequent steps, where specific disciplinary language must be employed. Finally, also the use of ICT and mathematical tools which are perceived by the students as belonging to the university and employment world can increase students’ perception of value

Resezione epatica maggiore con modulazione del flusso portale nel ratto: studio emodinamico e ruolo della Serpina B3 sul danno cellulare

Background: The increased blood flow per gram of liver immediately after liver resection results in an increase intrahepatic shear stress that seems to be involved in the stimulation and regulation of regeneration. A portal hyperflow however causes a serious liver damage due to high intraparenchymal shear stress. This phenomenon has been studied mainly in living donor liver transplantation or cadaveric split liver and in extreme liver resections. The result is a syndrome defined Small for Size which has many similarities with liver failure after hepatectomy and it is associated with severe morbidity and mortality. Among the mechanisms of cell protection and regeneration after liver resection, the Serpin B3 (serine protease inhibitor with anti-apoptotic action) could have a role in the control of apoptosis. The portal flow modulation through the use of port-caval shunt, embolization of the splenic artery, splenectomy has been proposed to prevent the damage due to a high shear stress. Aim of the study: The aim of the study is the analysis of hemodynamic changes assessed by ultrasound of the portal and hepatic artery circulation in rats after major liver resection and liver resection associated with splenectomy and their impact on the parenchymal damage. The study also aims to assess the relationship between the Serpin B3 expression and cell damage after resection in different groups of animals. Material and Methods: 23 male Wistar rats were divided into 4 groups: Group A (5 animals) underwent a 30% liver resection, Group B (8) 60% resection, the Group C (7) 60% resection associated with splenectomy and Group D (3) constituted the control group and underwent a simple laparotomy (sham operated). Immediately before surgery (T0) and after two hours (T1) blood samples were drawn from each rat (dosage of AST, ALT, LDH, lactic acid and ammonium). Samples of liver tissue were collected after the resection and 2 hours after surgery. An hepato-splenic echo-color Doppler was done at T0 and T1 in all the rats. On bioptic samples of the various groups, in addition to standard histopathological analysis, the extraction and quantification of RNA Serpin B3 was performed. On the same biopsies the apoptotic index quantification was tested with TUNEL. Results: The eco-Doppler study showed a portal flow per gram of liver in group B greater than the other 3 groups. Only in group B the hepatic arterial resistance had increased significantly; also the resistance of the splenic artery appeared increased. In group C, there was a tendency to reduction in portal flow and also the hepatic arterial resistance tended to decrease in this same group. The expression of Serpin B3 in group B increased more than the other groups. The TUNEL test showed a greater degree of apoptosis in group C than in group B and in the control. Conclusions: The post-resection liver damage is already present 2 hours after hepatectomy and it is probably due to the hemodynamic changes that this causes. The role of Serpina B3 has not been yet clarified in the protection of the damage after major liver resection; what we have seen in our study is that to a greater expression of Serpin B3 is associated a lower apoptosis

Are collapse models testable with quantum oscillating systems? The case of neutrinos, kaons, chiral molecules

Collapse models provide a theoretical framework for understanding how classical world emerges from quantum mechanics. Their dynamics preserves (practically) quantum linearity for microscopic systems, while it becomes strongly nonlinear when moving towards macroscopic scale. The conventional approach to test collapse models is to create spatial superpositions of mesoscopic systems and then examine the loss of interference, while environmental noises are engineered carefully. Here we investigate a different approach: We study systems that naturally oscillate --creating quantum superpositions-- and thus represent a natural case-study for testing quantum linearity: neutrinos, neutral mesons, and chiral molecules. We will show how spontaneous collapses affect their oscillatory behavior, and will compare them with environmental decoherence effects. We will show that, contrary to what previously predicted, collapse models cannot be tested with neutrinos. The effect is stronger for neutral mesons, but still beyond experimental reach. Instead, chiral molecules can offer promising candidates for testing collapse models.Comment: accepted by NATURE Scientific Reports, 12 pages, 1 figures, 2 table

Fundamental frontiers of quantum science and technology

We discuss recent studies on the foundations of quantum physics with photonic, atomic, molecular and micromechanical systems as well as theoretical treatments of the interface between quantum physics and classical observations. Investigations of the type presented here elucidate important boundary conditions for quantum mechanics and help assessing their relevance for future quantum technologies. © Selection and peer-review under responsibility of FET11 conference organizers and published by Elsevier B.V

Are Collapse Models Testable via Flavor Oscillations?

Collapse models predict the spontaneous collapse of the wave function, in order to avoid the emergence of macroscopic superpositions. In their mass-dependent formulation they claim that the collapse of any system's wave function depends on its mass. Neutral K, D, B mesons are oscillating systems that are given by Nature as superposition of different mass eigenstates. Thus they are unique and interesting systems to look at, for analyzing the experimental implications of such models, so far in agreement with all known experiments. In this paper we derive - for the single mesons and bipartite entangled mesons - the effect of the mass-proportional CSL collapse model on the dynamics on neutral mesons, including the relativistic effects. We compare the theoretical prediction with experimental data from different accelerator facilities.Comment: 20 pages, RevTe