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Shallow landslides are phenomena involving small parts of land and are triggered by huge intensity rainfall events of short duration or more moderate but prolonged over time. The area and thickness of such slips are typically reduced, but they are still harmful because there are no warning signs and no information on their possible evolution.Since the middle of the 20th century, heavy precipitation events have been more frequent and intense. In light of the current climate crisis, it is crucial to thoroughly examine the effects of these occurrences in order to establish triggering thresholds in mountain regions. This work deals with the experimental study of these landslides through the laboratory simulations on a small-scale slope, reproduced at the Gap2 lab of the Lecco Campus. Different experiments have been performed reproducing the seasonal conditions of the slopes. In particular, extreme rainfall events, soil conditions with different volumetric water content percentages were compared with moderate rainfall events in order to assess the different timing of landslide triggering.To investigate the behaviour of surface landslides under these conditions and to visualise in detail the processes related to water circulation, a multidisciplinary approach was adopted that consist of observations using geological, geophysical and photogrammetric methodologies and instrumentation. These technologies include modified pressure transmitters for the pore water pressure evaluation, GoPro’s cameras, TDR (Time Domain Reflectometry) for the volumetric water content evaluation and a georesistivimeter (IRIS Syscal Pro). In this way hydrogeological processes can be deeply analysed from different perspectives and can highlight peculiarities and assess in detail their evolution leading to collapse.Through the information obtained from geophysics, it is possible to visualise the formation of cracks within the landslide body in advance, also allowing considerations regarding the different water contributions of the simulated rainfall and the initial water content in the soil. The experimental results were then compared with a mathematical model.

Internationale katholische Zeitschrift Communio, Bd. 35 Nr. 3 (2006): Internationale katholische Zeitschrift Communio, Band 35, Heft 3

Fluorescent probes for biological imaging have revealed much about the functions of biomolecules in health and disease. Fluorogenic probes, which are fluorescent only upon a bioorthogonal reaction with a specific partner, are particularly advantageous as they ensure that fluorescent signals observed in biological imaging arise solely from the intended target. In this work, we report the first series of naphthalimide tetrazines for bioorthogonal fluorogenic labelling. We establish that all of these compounds can be used for imaging through photophysical, analytical and biological studies. The best candidate was Np6mTz, where the tetrazine ring is appended to the naphthalimide at its 6-position via a phenyl linker in a meta configuration. Taking our synthetic scaffold, we generated two targeted variants, LysoNpTz and MitoNpTz, which successfully localized within the lysosomes and mitochondria respectively, without the requirement of genetic modification. In addition, the naphthalimide tetrazine system was used for the no-wash imaging of insulin amyloid fibrils in vitro, providing a new method that can monitor their growth kinetics and morphology. Since our synthetic approach is simple and modular, these new naphthalimide tetrazines provide a novel scaffold for a range of bioorthogonal tetrazine-based imaging agents for selective staining and sensing of biomolecules., New naphthalimide tetrazine probes permit fluorescent imaging of biomolecules in vitro and in living cells. They can be modified to provide previously unknown information about health and disease in biological systems.

We investigate Raman scattering of MoSe 2 crystals with excitation energies in the visible and in the infrared (from 1.16 eV to 2.33 eV). We show that, despite the lower scattering efficiency at longer wavelengths, it is possible to measure also MoSe 2 monolayers with photon energy of 1.16 eV, by placing the flakes on hexagonal BN slabs on Au substrates.The lineshape of the Raman modes is shown to be highly dependent on the excitation energy due to resonant processes. In particular, we observe effects of resonant Raman scattering with the indirect band gap (1.14 eV) of MoSe 2 yielding information on the electronic and phonon density of states. By the calculation of the two-phonon density of states in different position of the Brillouin zone, we are able to reproduce some experimental features of the second order Raman spectra.

Johanna Graziotto (Studentin der Germanistik und Geschichtswissenschaft) berichtet über ihre Erfahrungen im Marsilius Brückenseminar „Bioökonomie als Garant für Nachhaltigkeit? - Naturwissenschaftliche Grundlagen, politische Herausforderungen und gesellschaftliche Akzeptanz“ (Marsilius Studien)., Forum Marsilius-Kolleg, Bd. 19 (2021): Jahresbericht 2019/2020

Platinum-based chemotherapeutics are widely used for chemotherapy, but their continued use is restricted by patient side effects and resistance. To maximise efficacy and minimise side effects, there is a need to personalise the treatment to the patient and their cancer, which requires a better understanding of the biological interactions of platinum complexes. This thesis has investigated these interactions through new strategies and techniques. Novel monofunctional platinum complexes were investigated in order to distinguish how these complexes differ from clinical agents. Two members of the series had a dramatic divergence in cytotoxicity which was ascribed to their cellular accumulation. Their protein binding profiles were characterised by SEC-ICP-MS for the first time, indicating that the monofunctional complexes react with unique intracellular protein targets. Fluorogenic probes were recognised as tools that would help to unravel further information on biological platinum interactions. With no fluorogenic naphthalimide tetrazines reported to date, a novel series of compounds were synthesised. These compounds exhibited a strong fluorogenic response in vitro and in vivo. Their versatility was demonstrated by labelling of insulin fibrils for high-resolution imaging. Based on this scaffold, probes that monitor organelle health were developed. The first probe reported on the distribution of lysosomes within cells. The second probe had a fluorescent response that was sensitive to the mitochondrial membrane potential, which is an indicator of cellular health. Both probes were used in preliminary studies with platinum complexes, revealing that the mitochondria are disrupted and that the lysosomes do not change after 1 h of treatment. The tools developed in this work have revealed insights about how platinum complexes interact with cells. It highlights the importance of studying these interactions and their translation to the clinic to improve patient outcomes.

Ge/SiGe heterostructures are promising in the view of silicon-foundry compatible THz optoelectronic applications. Here we present a structural and optical characterization of Ge/SiGe parabolic quantum wells that represent ideal systems for room-temperature THz emission and strong light-matter coupling investigation.

Selective fluorescent probes enable unprecedented studies of metals, with sensitivity not only to identify the metal, but also to discern its oxidation state and coordination environment. Recent work has highlighted the potential of fluorescent probes for specific platinum species in understanding the activity of platinum anticancer agents. Here we report a rhodamine-based probe that selectively responds to aryl-bearing trans-platinum complexes, which represent an important class of potential anticancer agents. We subsequently demonstrate the utility of this probe for studying the rate of metabolism of these types of complexes.