Wilson-loop correlators on the lattice and asymptotic behaviour of hadronic total cross sections

We show how universal, Froissart-like hadronic total cross sections can be obtained in QCD in the functional-integral approach to soft high-energy scattering, and we discuss indications of this behaviour obtained from lattice simulations.Comment: Presented at EDS Blois 2013 (arXiv:1309.5705

In vitro models of breast cancer bone metastasis: analyzing drug resistance through the lens of the microenvironment

Even though breast cancers usually have a good outcome compared to other tumors, the cancer can progress and create metastases in different parts of the organism, the bone being a predilection locus. These metastases are usually the cause of death, as they are mostly resistant to treatments. This resistance can be caused by intrinsic properties of the tumor, such as its heterogeneity, but it can also be due to the protective role of the microenvironment. By activating signaling pathways protecting cancer cells when exposed to chemotherapy, contributing to their ability to reach dormancy, or even reducing the amount of drug able to reach the metastases, among other mechanisms, the specificities of the bone tissue are being investigated as important players of drug resistance. To this date, most mechanisms of this resistance are yet to be discovered, and many researchers are implementing in vitro models to study the interaction between the tumor cells and their microenvironment. Here, we will review what is known about breast cancer drug resistance in bone metastasis due to the microenvironment and we will use those observations to highlight which features in vitro models should include to properly recapitulate these biological aspects in vitro. We will also detail which elements advanced in vitro models should implement in order to better recapitulate in vivo physiopathology and drug resistance

Video selection for visual sensor networks: A motion-based ranking algorithm

A Visual Sensor Network (VSN) is composed by several cameras, in general with different characteristics and orientations, which are used to cover a certain Area of Interest (AoI). To provide an optimal and autonomous exploitation of the VSN video streams, suitable algorithms are needed for selecting the cameras capable to guarantee the best video quality for the specific AoI in the scene. In this work, a novel content and context-aware camera ranking algorithm is proposed, with the goal to maximize the Quality of Experience (QoE) to the final user. The proposed algorithm takes into account the pose, camera resolution and frame rate, and the quantity of motion in the scene. Subjective tests are performed to compare the ranking of the algorithm with human ranking. Finally, the proposed ranking algorithm is compared with common objective video quality metrics and a previous ranking algorithm, confirming the validity of the approach

People’s Republic of Bolzano or how digital artifacts can be adversarial to misinformation

Design scholars have been focusing more of their attention to public controversial “things”, through the focus on “making public things” or on the “formation of publics” in relation to design projects. With this in mind, this paper describes a design case contrasting and challenging the main media narrative through the production of digital artifacts. The design intervention we describe, aimed at counteracting the racist stereotyping which targets the local Chinese community of Bolzano. The project People’s Republic of Bolzano reshapes the identity of the local Chinese community through digital media, in order to restore more transparent and balanced information, allowing a broader audience to inform itself on such a complex and multifaceted issue. This small project is part of an emergent phenomenon to counterbalance misrepresentation, in this case over the issue of migration

Operatori covarianti, operatori tensoriali irriducibili e teorema di Wigner-Eckart

In questa tesi viene innanzitutto analizzato il legame tra la simmetria rotazionale e il momento angolare di un sistema quantistico. Vengono poi studiate le proprietà generali degli operatori covarianti per rotazione, in particolare gli operatori scalari, vettoriali e diadici. Viene quindi esposta la teoria generale degli operatori tensoriali irriducibili che permette una trattazione unificata delle varie tipologie di operatori covarianti. Vengono in particolare studiati due teoremi fondamentali: il teorema di Wigner-Eckart e della proiezione. Sono illustrate infine alcune applicazioni

An update of the on-sky performance of the Layer-Oriented wave-front sensor for MAD

The Multi-conjugate Adaptive optics Demonstrator, MAD, successfully demonstrated on sky the MCAO technique both in Layer Oriented and Star Oriented modes. As results of the Guaranteed Time Observations in Layer Oriented mode quality astronomy papers have been published. In this paper we concentrate on the instrumentation issues and technical aspects which stay behind this success.Comment: 12 pages, 10 figures, Proceedings of the SPIE conference "Adaptive Optics Systems II", 27 June 2010, San Diego, California, US

Environmental selection of the cosmological constant and electroweak scales

We investigate whether selfish/Goldilocks Higgs models can be extended to accomodate vacua with both the right Higgs mass and cosmological constant. Through the introduction of multiple four-form fields coupled with the Higgs scalar boson we find that both the cosmological constant and the electroweak hierarchy problems can be addressed simultaneously, without inserting the relevant physical scales by hand and avoiding fine tuning. The resulting bounds on the brane charges, the only dimensionful free parameter of the theory, depend on the strength of the four-form scalar coupling and can be of the same order of magnitude as those necessary for a solution to the cosmological constant problem alone via the Bousso-Polchinski mechanism

Spatio-temporal distribution pattern of COVID-19 in the Northern Italy during the first-wave scenario. The role of the highway network

Background: The rapid outbreak of Coronavirus disease 2019 (COVID-19) has posed several challenges to the scientific community. The goal of this paper is to investigate the spread of COVID-19 in Northern Italy during the so-called first wave scenario and to provide a qualitative comparison with the local highway net. Methods: Fixed a grid of days from February 27, 2020, the cumulative numbers of infections in each considered province have been compared to sequences of thresholds. As a consequence, a time-evolving classification of the state of danger in terms of Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections, in view of the smallest threshold overtaken by this comparison, has been obtained for each considered province. The provinces with a significant amount of cases have then been collected into matrices containing only the ones featuring a significant amount of cases. Results: The time evolution of the classification has then been qualitatively compared to the highway network, to identify similarities and thus linking the rapid spreading of COVID-19 and the highway connections. Conclusions: The obtained results demonstrate how the proposed model properly fits with the spread of COVID-19 along with the Italian highway transport network and could be implemented to analyze qualitatively other disease transmissions in different contexts and time periods

Oscillating Cell Culture Bioreactor

To better exploit the principles of gas transport and mass transport during the processes of cell seeding of 3D scaffolds and in vitro culture of 3D tissue engineered constructs, the oscillatory cell culture bioreactor provides a flow of cell suspensions and culture media directly through a porous 3D scaffold (during cell seeding) and a 3D construct (during subsequent cultivation) within a highly gas-permeable closed-loop tube. This design is simple, modular, and flexible, and its component parts are easy to assemble and operate, and are inexpensive. Chamber volume can be very low, but can be easily scaled up. This innovation is well suited to work with different biological specimens, particularly with cells having high oxygen requirements and/or shear sensitivity, and different scaffold structures and dimensions. The closed-loop changer is highly gas permeable to allow efficient gas exchange during the cell seeding/culturing process. A porous scaffold, which may be seeded with cells, is fixed by means of a scaffold holder to the chamber wall with scaffold/construct orientation with respect to the chamber determined by the geometry of the scaffold holder. A fluid, with/without biological specimens, is added to the chamber such that all, or most, of the air is displaced (i.e., with or without an enclosed air bubble). Motion is applied to the chamber within a controlled environment (e.g., oscillatory motion within a humidified 37 C incubator). Movement of the chamber induces relative motion of the scaffold/construct with respect to the fluid. In case the fluid is a cell suspension, cells will come into contact with the scaffold and eventually adhere to it. Alternatively, cells can be seeded on scaffolds by gel entrapment prior to bioreactor cultivation. Subsequently, the oscillatory cell culture bioreactor will provide efficient gas exchange (i.e., of oxygen and carbon dioxide, as required for viability of metabolically active cells) and controlled levels of fluid dynamic shear (i.e., as required for viability of shear-sensitive cells) to the developing engineered tissue construct. This bioreactor was recently utilized to show independent and interactive effects of a growth factor (IGF-I) and slow bidirectional perfusion on the survival, differentiation, and contractile performance of 3D tissue engineering cardiac constructs. The main application of this system is within the tissue engineering industry. The ideal final application is within the automated mass production of tissue- engineered constructs. Target industries could be both life sciences companies as well as bioreactor device producing companies