Erik Franco – Pagina 5 – Progress in Research

Pioneering study sheds light on poorly understood aspect of cancer

Posted on 19/09/202306/08/2024 by Erik Franco

A new scientific study published in the journal Science Advances has investigated a still poorly understood aspect of cancer, therapy-induced senescence in tumor cells. The study, the result of collaboration between researchers from Politecnico di Milano, Johns Hopkins University in Baltimore, the National Cancer Institute in Milan, and the National Research Council, expands our understanding of cancer biology and paves the way for future therapeutic advancements.

The team worked to uncover the biological mechanisms behind the formation of “therapy-induced senescent” (TIS) cells, a small percentage of treated tumor cells that exhibits resistance to conventional therapies (chemotherapy and radiation therapy), leading to tumor quiescence and ultimately, recurrence.

This result is a clear example of how cutting-edge technologies, multidisciplinary expertise, and strong international collaborations are crucial in addressing the most pressing biological questions, such as the early reaction mechanisms of tumor cells to anticancer therapies.
Arianna Bresci, first author of the study and doctoral student at Department of Physics

Researchers utilized advanced optical microscopy techniques, combining three-dimensional holograms of tumor cells with ultra-short pulses of laser light. They explored both the chemical and morphological aspects of TIS cells in human tumors, without the use of invasive techniques, preserving the natural state of the cells.

The research group was able to distinguish key features of TIS cells in human tumor cells: the reorganization of the mitochondrial network, overproduction of lipids, cell flattening, and enlargement. By analyzing a considerable number of cells, researchers established a clear timeline for the development of these distinctive signs.

This discovery may lead to applications in the development of personalized treatments and the possibility of refining current screening protocols for oncology therapy.

Our findings provide important insights into the complex world of TIS in human tumor cells. In our laboratory at Politecnico di Milano, we have developed a new non-invasive laser microscope that has allowed us to understand the initial stages of this phenomenon.
Dario Polli, associate professor at Department of Physics and coordinator of the study

Crucial discovery on the ultrafast charge injection in semiconductors

Posted on 13/09/202306/08/2024 by Erik Franco

The capability to follow and control ultrafast electron dynamics in matter with light pulses is a long-sought goal, with important implications in many fields of technology and research. In a semiconductor, for example, charge injection by few-femtosecond infrared pulses could be used to turn the material into a conductive state, realizing ultrafast switches in opto-electronics, a milestone that promises to increase the limiting speed of data processing and information encoding. This technological breakthrough can only stem from a comprehensive knowledge of light-induced charge injection, a key challenge of modern solid-state physics and photonics.

A study published in Nature Photonics tackles this problem by investigating field-driven carrier injection in a prototype semiconductor (monocrystalline germanium) with attosecond transient reflection spectroscopy: the researchers from Politecnico di Milano, in collaboration with the Istituto di Fotonica e Nanotecnologie (IFN-CNR), the Istituto per la microelettronica e microsistemi (CNR-IMM), the Istituto Nanoscienze (CNR-NANO) and a group from the Università degli Studi di Salerno, have discovered a new light-matter interaction regime where charges are excited by diverse coexisting mechanism. These mechanisms compete and develop on different time scales, of the order of few millionths of billionth of a second.

The researchers succeeded in disentangling the complex charge injection regime on these extreme temporal scales thanks to the experiments performed by the Attosecond Research Centerwithin the ERC project AuDACE (Attosecond Dynamics in AdvanCed matErials) and the PRIN project aSTAR. By means of simulations based on advanced theoretical models, they have shown the complex interaction between diverse mechanisms in the quantum-mechanical response of the material, never observed before, with important implications in many fields as optics, photonics, and information technology.

Those are significant results because the knowledge of the excitation processes induced by light in semiconductors allows us to design new opto-electronic devices with optimized ratio between charge injection speed and dissipated power.
Matteo Lucchini, professor of the Department of Physics and last author of the study

Read the study online

Ultra-fast response of carbon atomic wires to light discovered

Posted on 08/09/202306/08/2024 by Erik Franco

A study resulting from the collaboration between the Department of Energy and the Department of Physics of Politecnico di Milano and the Department of Chemistry of the University of Bologna has been published in the Journal of the American Chemical Society as the cover article.

The team of researchers made a discovery that sheds new light on the properties of wire-shaped carbon nanostructures, also known as ‘polyynes’. Composed of few carbon atoms, these wires could revolutionise technological applications due to their extraordinary mechanical, thermal and electronic properties.

This study lays the foundation for new technological opportunities. Understanding how these nanostructures interact with light is crucial to exploiting their full potential in areas such as opto-electronics and renewable energy,
Giulio Cerullo and Margherita Zavelani-Rossi, co-authors of the article

At the heart of the research is the study into how these nanostructures react to light. Using state-of-the-art technology and ultra-short laser pulses, the researchers synthesised these structures in a controlled manner and examined their optical properties in detail. This allowed them to reveal the mysteries of the reactions triggered by light in these nanostructures.

The most surprising findings arise from the speed of the processes observed. In particular, when hit by light, these nanostructures rapidly switch from an excited state to a more stable one, all in an incredibly short time, just 200 millionths of a billionth of a second.

This discovery has significant implications for technology. Understanding how these nanostructures react to light could pave the way for new applications, such as advanced electronic devices and solar energy conversion technologies.

Carbon nanostructure research is a complex and upcoming field. Our findings represent a step forward in the understanding of these structures and their potential applications.
Carlo Casari, co-author of the article

Read the study online

The end of hydropower in Africa

Posted on 25/08/202306/08/2024 by Erik Franco

Most of the new dams proposed all over Africa should not be built, according to a study published in Science magazine carried out by researchers from the Politecnico di Milano with colleagues from the Institute for Applied Systems Analysis (IIASA) in Austria, the Vrije Universiteit Brussel (VUB) and the World Resources Institute in Addis Ababa (Ethiopia). Authors include Angelo Carlino, former PhD student at the Politecnico di Milano and now a postdoc at the Carnegie Institution for Science at Stanford, Professor Andrea Castelletti, lecturer in Natural Resource Management at the Politecnico, and Matteo Giuliani, researcher at the Department of Electronics, Information and Bioengineering of the Politecnico.

The research used a very detailed energy model to identify the most cost-effective combination of energy sources with which African countries could meet the growing demand for electricity until 2050 and, in particular, which plants could be a clever investment and which should instead not be built.

According to the analysis, up to 67% of possible future hydropower plants in Africa are not worth the investment, mainly due to the fact that hydropower will soon no longer be economically competitive as compared to solar power or (to a lesser extent) wind power, the costs of which have fallen at an unprecedented rate over the past ten years. However, especially in the Congo, Niger and Nile Basins, there are projects that are worth implementing in the short term, provided they are well planned and their harmful environmental effects are minimised.

The study also points out that further investments will be needed to mitigate the effects on hydropower of prolonged droughts, which are likely to worsen due to climate change. This is another reason why solar energy will emerge as the most appealing technology in the long run, to be prioritised in most African countries.

The results of the study are generally good news for the environment: it means that fewer dams will be built and therefore many rivers will be able to maintain their natural course.

The study published on Science magazine

Photo © DAFNE Project | Politecnico di Milano ＋ ATEC-3D

New ultrafast titanium nitride-based photonics

Posted on 23/08/202306/08/2024 by Erik Franco

A study resulting from the collaboration between the Department of Energy and the Department of Physics of Politecnico di Milano and supported by an interdisciplinary PhD research by Silvia Rotta Loria has been published in the journal Advanced Optical Materials as a cover article.

The study explains the origin of the ultrafast optical response of titanium nitride (TiN). This material, already knownfor its refractory properties, is also attracting increasing interest because of its fast response to photo-excitation and the possibility of controlling its optical and electronic properties during synthesis.
TiN films have already been used for thermo-photovoltaic devices, for artificial photosynthesis or for micro super-capacitors on chips. Moreover, TiN is compatible with technologies used in digital electronics. Overall, it is therefore a material with a great potential for developing ultrafast photonic devices.

This collaboration has made it possible to thoroughly study this material of great technological interest and to clarify the origin of its peculiar response to light excitation, which can be engineered through the manufacturing procedure,
Prof. Margherita Zavelani Rossi, Department of Energy, co-author of the paper

The study was carried out thanks to the synergy between two Departments of Politecnico: TiN films were made in the NanoLab (Micro and Nanostructured Materials Lab) of the Department of Energy, were then characterised in the ultrafast spectroscopy laboratories of the Department of Physics, and the experimental data were interpreted using a model developed in the Department of Physics.

Thanks to the accurate numerical model developed, it is now possible to determine how the response of a titan nitride thin film can be controlled through light; this knowledge is crucial for developing new miniaturised opto-electronic and photonic devices,
Prof. Giuseppe Della Valle, Department of Physics, co-author of the paper

The experiment mentioned in the paper is one of the outcomes of the METAFAST project funded by the European Union’s H2020-FET-OPEN programme, coordinated by Prof. Giuseppe Della Valle. The project aims to develop a new class of ultrafast optical devices based on special nanostructured surfaces (nonlinear metasurfaces).

Read the study

The official METAFAST project website

Oxygen from lunar regolith

Posted on 31/07/202306/08/2024 by Erik Franco

Agenzia Spaziale Italiana (ASI) and Politecnico di Milano have signed an agreement concerning the ambitious project to develop and validate one of the key technologies to enable long-term human presence on our natural satellite. The ORACLE (Oxygen Retrieval Asset by Carbothermal-reduction in Lunar Environment) project is aimed at extracting oxygen from the lunar regolith, the fragmented rock that cover the surface of the Moon, according to a process already studied in the laboratory by the ASTRA group of Politecnico di Milano.

Now, under the guidance of ASI, a validation in the target operational environment, i.e., the surface of the Moon, is to be implemented by the end of this decade.

In Situ Resources Utilisation, i.e., the on-site extraction and exploitation of resources, is a key capability for sustainable exploration such as the one we are planning for the Moon. In this sense, we expect the ORACLE to be of global interest in a future perspective and to enable Italy, among the first in the world, to hold a strategic technology. In this new season of return to the Moon, our country is making the best preparations to participate, and ORACLE will give us the opportunity to consolidate our leading role in large-scale programmes such as Artemis.
Raffaele Mugnuolo, Head of the ASI’s Exploration, Orbiting and Surface Infrastructures and Scientific Satellites Unit

With this agreement, ASI and Politecnico undertake to collaborate right from the initial stages in the design and definition of the interface aspects of the lander that will host a preliminary version of the system. In the upcoming years development activities will be carried out that will be entrusted to an industrial partner. The goal is to build a demonstrator that can be launched by 2028 making use of one of the commercial flight opportunities among those currently under development in several countries.

The ORACLE project represents a virtuous path of research and technological development that demonstrates how innovation can be realised through the synergetic actions of complementary worlds such as the University, ASI and, in the future, the national industrial sector. ORACLE further confirms that the collaboration between the two institutions in the aerospace field creates opportunities to put the technical skills and research of Politecnico di Milano at the service of consolidating Italy’s role in such a strategic sector worldwide. The challenge is considerable, and just as intense are the motivation and enthusiasm of the team that will actively work for the return to the Moon, which is a unique historical moment in the space exploration scenario and follows up on the results obtained in the laboratory to produce the first lunar water droplet ‘on-site’.
Michèle Lavagna, Scientific Project Co-ordinator Project for Politecnico di Milano

Quantum tunnelling of electrons in bidimensional materials

Posted on 26/07/202306/08/2024 by Erik Franco

Sustainable optical computers based on photonic logic gates with low power consumption, but also nano-scaled (one billionth of a metre) optical chips and novel sensors with high sensitivity: the research carried out by an international team opens those new intriguing perspectives for the near future. The team is coordinated by Politecnico di Milano – Department of Physics in collaboration with University of Sheffield (UK); researchers from University of Manchester and Exeter (UK) collaborated too.

The researchers observed that the effect of quantum tunnelling of electrons between two adjacent layers of atomically thin semiconductors drastically modifies their transparency, after being illuminated by laser light.

The work has been recently published on the prestigious journal Nature Communications.

More in details, the research team explored the effects of this bidirectional “transport” of electrons between a layer of an atomically thin material to another one, the so-called quantum tunnelling.

Because of this transfer, the electrons are delocalized among the layers and they compete with the electrons localized in only one layer to occupy the same energetic state. This phenomenon follows the so-called Pauli exclusion principle, which also hinders the light absorption if the states are already occupied by the electrons. This process can strongly modify the optical properties of the employed materials, increasing their transparency after the illumination with laser light.

In summary, the competition between electrons generates a drastic decrease of the light absorption in such materials, increasing their laser-induced transparency.

The observation of such properties paves the way for new research horizons in the field of photonics and materials science, for future applications in optical and quantum computing.

The work was partially funded by the European Union in the framework of the Graphene Flagship (project “GrapheneCore3” lead by Prof. Giulio Cerullo) and the Marie Curie Individual Fellowship project “Enosis” lead by Dr. Armando Genco.

The paper on Nature Communications

Fibre optics against water wastage

Posted on 25/07/202306/08/2024 by Erik Franco

Using fibre optic sensors to monitor water networks against wastage: the international journal Sensors published the results of an experiment carried out at Politecnico di Milano aimed at optimising the water network.

Researchers from the Department of Civil and Environmental Engineering pioneered the use of distributed fibre optic sensing (DFOS) based on Stimulated Brillouin Scattering (SBS) technology for monitoring water pipeline networks over long distances. At the heart of this technology is the common and inexpensive optical fibre used for telecommunications (which brings the internet into our homes) capable of measuring deformations to a hundredth of a millimetre.

The scholars worked on High Density Polyethylene (HDPE) piping, today the most commonly used material for distribution systems. By wrapping and fixing the fibre optic sensor cable on the outer surface of the pipe, they tested the ability to detect deformations related to pressure anomalies along a pipe, such as those caused by water leaks.

In the future, the tested technology will be further developed towards industrial-scale production of ‘natively smart’ HDPE pipes, where DFOS are integrated into the pipe surface during the extrusion process.

The study was signed by Manuel Bertulessi, Daniele Fabrizio Bignami, Ilaria Boschini, Marina Longoni, Giovanni Menduni and Jacopo Morosi.

The paper published in Sensors

Innovative wings for the NGCTR-TD civil tiltrotor

Posted on 24/07/202306/08/2024 by Erik Franco

The activities of the FORMOSA (FunctiOnal aiRcraft MOveable SurfAces) project, launched in 2020 to redesign the wing control surfaces of the NextGen Civil TiltRotor (NGCTR-TD) civil tiltrotor produced by Leonardo, have recently come to an end.

A tiltrotor is a hybrid aircraft that combines the characteristics of a helicopter with those of an airplane. The architecture of tiltrotors features two rotors, placed at the wingtips, which can rotate allowing the aircraft to take off (and land) vertically and, once the take-off manoeuvre is complete, rotate forward to turn into propellers, producing the thrust for flight, as in a classic propeller plane.

The project, co-ordinated by Prof. Vincenzo Muscarello (Department of Aerospace Science and Technology) and funded by the European Clean Sky 2 programme, has made it possible to reduce the load of wakes on the wings in helicopter mode (-9% compared to the original project), enabling a reduction in fuel consumption during vertical take-off and landing manoeuvres. In addition, a significant improvement in roll performance was achieved during flight in airplane mode, thanks to a 25 per cent reduction in the time-to-bank, the time needed to reach the required turning angle.

The NextGen Civil TiltRotor is a technology demonstrator designed by Leonardo as part of the European Clean Sky 2 programme and created to meet, among other things, the growing need for air mobility in densely populated urban areas, offering the opportunity to take off and land vertically like a helicopter, together with the high speed distance capability typical of airplanes.

The FORMOSA (FunctiOnal aiRcraft MOveable SurfAces) consortium consists of a group of young researchers from Politecnico di Milano and a team of engineers from the Portuguese company CEiiA (Centre of Engineering and Product Development).

Recovery of high value-added proteins from poultry industry waste

Posted on 17/07/202306/08/2024 by Erik Franco

Today, the animal-based food industry is one of the most critical and environmentally impactful: in the European Union alone, poultry farms produce more than 3 million tonnes of feather waste annually which is incinerated, thus releasing polluting by-products into the atmosphere.

In this context, the KARATE (Keratin smARt mATerials from feather wastE) project, coordinated by Politecnico di Milano and funded by Fondazione Cariplo within the framework of the call Circular Economy – Promoting research for a sustainable future, aims at reducing the environmental impact of the poultry production chain, contributing significantly to the revaluation and reuse of its waste, in order to transform it into high added value products. In particular, KARATE envisages the valorisation of waste feathers as a raw material for obtaining organic molecules of broad interest such as peptides and proteins, to be used as a basis for developing intelligent, high-performance biomaterials for the textile and biomedical sectors.

The project is coordinated by Pierangelo Metrangolo, full professor in Fundamentals of Chemistry for Technologies at the Department of Chemistry, Materials and Chemical Engineering “Giulio Natta” of Politecnico di Milano. It involves three other research partners (Fondazione Istituto Insubrico Ricerca per la Vita, Consorzio Italbiotec and Centro de Investigacións Científicas Avanzadas of the Universidade da Coruña) and 11 industrial entities (BiCT Bioindustry Innovation, Kialab, Klopman, Linari Engineering S.r.l., Lombardy Green Chemistry Association, Revita Technology, ROELMI HPC, Società Agricola Bruzzese S.S., Solvay Specialty Polymers, VEGEA).