Light Simulation with Participating Media

In this project we address the problem of light scattering in participating materials. We create a complete simulation of this phenomenon in a more general case than previous work. We analyse the directional part of light, in order to install a clear basis for future work. We derive two models from this analysis: the spherical Gaussians approximation and the double exponential approximation. These models are placed in the scope of the planned development of an improved method for scattering. We also code a custom ray tracer to have a complete pipeline of rendering and to understand the underneath concepts. The validation of our simulation is done by comparing against the results of Eugene d'Eon in his article of Quantized-diffusion.Dans ce projet, nous abordons le problème de la diffusion de la lumière dans des matériaux participant. Nous créons une simulation complète de ce phénomène dans un cas plus général que les travaux précédents. Nous analysons la partie directionnelle de la lumière, dans le but d'installer une base claire à de futurs travaux. Nous tirons deux modèles de cette analyse : l'approximation de gaussiennes sphériques et l'approximation de double exponentielle. Ces modèles sont placés dans le cadre de l'élaboration prévue d'une méthode amélioré pour la diffusion. Nous codons également un lanceur de rayons dans le but d'avoir un pipeline complet de rendu et de comprendre les concepts sous-jacents. La validation de notre simulation est effectuée en comparant avec les résultats de Eugene d'Eon dans son article Quantized-diffusion

Structural and functional characterization of human ERp44: a closer look at a member of PDI family regulating protein quality control in the early secretory pathway

The Endoplasmic Reticulum (ER) is the site of folding and assembly of secretory proteins. Fidelity of protein-based intracellular communication is guaranteed by protein quality control mechanisms located at the Early Secretory Compartment (ESC), which restricts forward transport to native proteins. ERp44 plays a key role in the Thiol-Mediated Retention (TMR) of variety of client proteins (Ero1, SUMF1, Adiponectin, IgM) thus regulating their transport and localization. Little is known about the molecular mechanisms of ERp44-TMR and how it is regulated in living cells. Hence, the overall aim of this work is to investigate the structure-function relationship of ERp44. In collaboration with Wang's group the crystal structure of ERp44 was determined. The structure of ERp44 most likely represents a non-reactive conformation of the protein. Indeed, Cys29 is shielded from the bulk solvent by C-terminal tail and almost inaccessible for the formation of intermolecular disulfide bonds with client proteins. Based on the obtained structural data and functional studies, a panel of mutants of ERp44 has been characterized in order to understand how C-terminal tail rearrangements expose substrate binding site, thus modulating substrates binding/ release in view of its role in TMR. Moreover, the pH gradient between ESC organelles was investigated as major determinant of C-terminal tail rearrangements. Given the known pH differences in the ESC, the data support the hypothesis of a role of the pH variation in governing ERp44-TMR activity in vivo. A deeper knowledge of the structure/function relationship of ERp44 will shed light on the protein quality control mechanisms thus providing essential knowledge of ESC processing diseases and in biotechnology, improving the production of man-made therapeutic proteins

La personalizzazione della ceramica domestica

Si presenta una raccolta esemplificativa di graffiti, su ceramica domestica di varia tipologia, incisi con l’intento di personalizzare l’oggetto. Essi vengono classificati in base al loro contenuto: semplice nome, nome del proprietario e dell’oggetto, oggetti parlanti.I present an illustrative collection of graffiti engraved on pieces of domestic pottery. The objective is their personalization. They are classed according to the matter: a simple name, the name of the owner and of the vase, speaking objects

Exploring Globalized Scenarios: The Case of Two Organizations in Venice, VeniSIA and Venywhere, that Aim at Contrasting Through Remote Work the Depopulation of Its Historic Centre

Although Venice has always been a popular tourist destination, the phenomenon has increased strongly in recent decades, leading to numerous protests from locals. Along with the increase in daily visitors, there have been a series of difficulties for citizens, from overcrowded public transport to the proliferation of souvenir shops, restaurants, and hotels. Many public properties have been sold by the Municipality itself to ensure their preservation in the face of high maintenance costs. Museums, palaces, and sometimes entire islands have been sold to private investors, often foreigners, who have turned them into tourist facilities, taking advantage of the city's fame. Venice in fact attracts between 12 and 20 million visitors every year, increasing year by year. But while the number of tourists rises, the number of inhabitants (of the historic centre) falls. On the 21st of March 2008, a historic pharmacy in the centre exposed a counter in the shop window that marks the number of citizens in real time: on that day it read 60,699 people. At the end of 2021, the number recorded was 50,434. To face the exodus of residents, the only measures taken by the Municipality concerned the regulation of tourist flows, with little if any results. The recent introduction of a reservation ticket to enter the city is only the latest of many measures with little use. In the last year, however, new organizations not linked to the Municipality were born with the ultimate aim of repopulating the historic centre by attracting a new class of residents. VeniSIA and Venywhere – the two organizations analysed in this study – want to exploit new technologies to create a new form of residency that may also have a positive impact on the lives of other inhabitants. Like overtourism, their existence can be defined as a 'side effect' of globalization. This study aims to find out whether the measures offered by these two organizations can really be effective in slowing down the exodus of residents and in what way. Should they prove successful, they would set an example that other cities suffering from overtourism could take inspiration fro

Insights into the Effect of Urban Morphology and Land Cover on Land Surface and Air Temperatures in the Metropolitan City of Milan (Italy) Using Satellite Imagery and In Situ Measurements

With a concentration of people, activities, and infrastructures, urban areas are particularly vulnerable to the negative effects of climate change. Among others, the intensification of the Urban Heat Island (UHI) effect is leading to an increased impact on citizen health and the urban ecosystem. In this context, this study aims to investigate the effect of urban morphology and land cover composition-which are established by exploiting the Local Climate Zone (LCZ) classification system-on two urban climate indicators, i.e., Land Surface Temperature (LST) and air temperature. The study area is the Metropolitan City of Milan (northern Italy). LCZ and LST maps are derived by leveraging satellite imagery and building height datasets. Both authoritative and crowdsourced in situ measurements are used for the analysis of air temperature. Several experiments are run to investigate the mutual relation between LCZ, LST, and air temperature by measuring LST and air temperature patterns in different LCZs and periods. Besides a strong temporal correlation between LST and air temperature, results point out vegetation and natural areas as major mitigating factors of both variables. On the other hand, higher buildings turn out to increase local air temperature while buffering LST values. A way lower influence of building density is measured, with compact building areas experiencing slightly higher air temperature yet no significant differences in terms of LST. These outcomes provide valuable tools to urban planners and stakeholders for implementing evidence-based UHI mitigation strategies

Self organized mode locking effect in superconductor / ferromagnet hybrids

The vortex dynamics in a low temperature superconductor deposited on top of a rectangular array of micrometer size permalloy triangles is investigated experimentally. The rectangular unit cell is such that neighboring triangles physically touch each other along one direction. This design stabilizes remanent states which differ from the magnetic vortex state typical of individual non-interacting triangles. Magnetic Force Microscopy images have revealed that the magnetic landscape of the template can be switched to an ordered configuration after magnetizing the sample with an in-plane field. The ordered phase exhibits a broad flux flow regime with relatively low critical current and a highly anisotropic response. This behavior is caused by the spontaneous formation of two separated rows of vortices and antivortices along each line of connected triangles. The existence of a clear flux flow regime even for zero external field supports this interpretation. The density of induced vortex-antivortex pairs is directly obtained using a high frequency measurement technique which allows us to resolve the discrete motion of vortices. Strikingly, the presence of vortex-antivortex rows gives rise to a self organized synchronized motion of vortices which manifests itself as field independent Shapiro steps in the current-voltage characteristics.Comment: 9 pages, 11 figure