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Optical microscopy uniquely provides non-invasive imaging of biological specimens and has become an essential tool in life sciences. So far, fluorescence microscopy techniques have been the most widely used due to their ability to visualize the molecules of interest with high contrast, high specificity, and high spatial and temporal resolution. In the last decades, much effort was put into the development of advanced super-resolution fluorescence microscopy techniques to circumvent the diffraction limit and image with unprecedented spatial resolution. The non-linearities contained in saturation phenomena were exploited for this purpose, and led to the development of techniques like stimulated emission depletion (STED) and saturated excitation (SAX) microscopy, which proved to have the potentiality to really break the diffraction barrier and tune the resolution down to infinitely small focal volumes (Chapter 1). Despite their well-established benefits, (super-resolution) fluorescence microscopy techniques rely on the photophysical properties of fluorescent molecules to obtain the desired contrast and resolution, and the labeling procedures may alter the physical properties of the specimen and may come at the cost of photobleaching and photodamage effects. With the development of ultrashort pulsed laser sources, new types of non-linear optical interactions became accessible (Chapter 1) and started to acquire a central role in optical microscopy for label-free imaging, providing novel non-fluorescence-based contrast mechanisms which purely rely on intrinsic properties of the molecules of interest. In this way, the invasiveness and the phototoxicity can be reduced, and the degradation of the fluorescence signal due to photobleaching can be avoided. Moreover, non-linear optical microscopy techniques allow for three-dimensional imaging due to the intrinsic optical sectioning capabilities of non-linear phenomena, while the use of longer wavelengths in the near-infrared part of the spectrum results in lower absorption and scattering and permits to image deeper inside tissues (Chapter 1). The main drawback of these non-linear optical microscopy techniques is their relatively poor spatial resolution, especially when using longer excitation wavelengths, and the fact that the imaging of non-fluorescent species with sub-diffraction resolution is still a challenging task. In this framework, this work aims at extending the super-resolution approaches to label-free microscopy techniques, based on the fact that, in principle, any saturable optical process between molecular states, not necessarily involving fluorescent transitions, is a potential candidate for breaking the diffraction barrier. In particular, non-linear optical processes are here exploited in near-infrared pump-probe microscopy techniques, such as transient absorption microscopy (TAM) and stimulated Raman scattering (SRS) microscopy (Chapter 3). In these techniques, two synchronized femto/picosecond pulsed laser beams are used to investigate ultrafast electronic and vibrational dynamical properties of the sample with high spatial and temporal resolution, high sensitivity and high chemical specificity. The interaction with the sample is recorded as an intensity variation of one of the two beams, which is extracted from the background adding a fast intensity modulation and filtering with a lock-in amplifier. New dynamical and chemical information can be accessed at the molecular level and in a label-free way, using intrinsic biomolecules as natural contrast agents. Absorption-based pump-probe microscopy is here optimized to retrieve structural and dynamical information from graphene-based samples with high sensitivity, and its conventional configuration is combined with an additional doughnut-shaped pump beam, which allows for the reduction of the effective focal volume exploiting transient absorption saturation. By optimizing the experimental parameters, such as power and temporal overlap of the saturation beam, single layer graphene deposited on a glass surface can be imaged at the nanoscale (Chapter 4). Moreover, the saturation of the vibrational excitation in SRS microscopy is here theoretically and experimentally assessed, in order to evaluate the applicability of the SAX approach to achieve isotropic sub-diffraction imaging capabilities (Chapter 5).

“Sperm donation”, “egg donation”, “double donation”, “embryo donation” and “embryo adoption” are the main terms that prospective parents in Italy employ to refer to donor reproductive practices, which are forbidden within Italian national territory since 2004. Italian residents who think of donated gametes or embryos as viable ways to parenthood currently need to address assisted reproduction centres abroad. Drawing on a four-year ethnographic research on Italian cross-border reproductive travellers approaching donor conception, this paper aims at investigating the ways in which prospective parents choose and make sense of different kind of donation practices that consist in the use of donor embryos and explores their understanding of such practices with reference to the notions of personhood and parenthood in a context of transnational reproduction. In particular, this paper explores how they make sense of different “histories” of embryos, included the way in which reproductive cells have changed owners according to different trajectories., Tecnoscienza – Italian Journal of Science & Technology Studies, Vol. 4 No. 1 (2013): Tecnoscienza Nr. 7

Defence date: 4 June 2013 Examining Board: Professor Martin Kohli, EUI (Supervisor); Professor Joan Bestard Camps, University of Barcelona (External Co-supervisor); Professor Fabrizio Bernardi, EUI; Professor Enric Porqueres i Gené, EHESS. PDF of thesis uploaded from the Library digital archive of EUI PhD theses The phenomenon of people crossing regional and national borders to seek assisted reproduction occurs in many countries across the world and involves different actors, including patients, doctors, fertility clinic practitioners, law-makers, donors, surrogates, children, brokers, and others who take part in the globalised industry of assisted reproductive technologies. This dissertation focuses on the experience of Italian reproductive travellers who seek donor conception treatments outside national borders, as a reaction to Italian regulations on assisted reproduction banning gamete donation in Italy. Through the qualitative analysis of the narrations and practices of heterosexual couples, same-sex couples and single women, this work explores the ways in which people face different reproductive itineraries with the aim of achieving reproduction through donor conception in a context of law evasion. In particular, it takes into account the process that leads people to choose donor conception abroad and investigates the ways in which people make sense of this choice in relation to their understanding of kinship formation. The feelings that accompany this process, the concepts that people mobilise to make both law evasion and donor conception practice coherent with their reproductive goals, and the strategies that they employ to "kin" their donor-conceived children are presented and analysed. This study highlights the fact that Italian CBRC travellers who seek donation treatments abroad mainly consider their reproductive experience as a transgressive act, because by doing so they circumvent laws that forbid those treatments locally. They tend to support the moral validity of their choices by arguing that it aims to accomplish what they perceive as a "normal" goal (having a child). Nonetheless, the recourse to such a reproductive experience challenges existing cultural understandings and the social organisation of kinship.

La presente legislación italiana sobre las técnicas de reproducción asistida (Ley 40 – 19 Febrero 2004) es una de las más restrictivas de Europa. Siguiendo un enfoque antropológico, este artículo intenta analizar el texto de esta ley en relación con sus respectivos debates públicos. El objetivo del análisis es señalar los valores morales que los legisladores quieren transmitir, el rol que ellos atribuyen a la ley como medida de influencia en las prácticas sociales, y el tipo de sociedad que ellos quieren modelar. El artículo se concentra especialmente en el significado que los conceptos de naturaleza, reproducción y familia adquieren en el contexto de esta ley y proporciona una visión general del marco legal, político y moral en el que esta ley fue concebida.