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    Split and overlapped binary solitons in optical lattices

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    We analyze the energetic and dynamical properties of bright-bright (BB) soliton pairs in a binary mixture of Bose-Einstein condensates subjected to the action of a combined optical lattice, acting as an external potential for the first species, while modulating the intraspecies coupling constant of the second. In particular, we use a variational approach and direct numerical integrations to investigate the existence and stability of BB solitons in which the two species are either spatially separated (split soliton) or located at the same optical lattice site (overlapped soliton). The dependence of these solitons on the interspecies interaction parameter is explicitly investigated. For repulsive interspecies interaction we show the existence of a series of critical values at which transitions from an initially overlapped soliton to split solitons occur. For attractive interspecies interaction only single direct transitions from split to overlapped BB solitons are found. The possibility to use split solitons for indirect measurements of scattering lengths is also suggested.Comment: 9 pages, 10 figure

    Management of severe epistaxis during pregnancy: a case report and review of the literature

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    Epistaxis is a common problem during pregnancy. Few cases of severe epistaxis, not associated with nasal lesions or clotting disorders, were described in the literature. We reported a case of severe epistaxis in a pregnant patient, exploring all the different possible management options

    Path dependence and institutional reform: A case study on the reform of Italian telecommunications institutions 1979-2007.

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    The theory of path dependence provides important claims to explain institutional development, relating to the roles of self-reinforcing process called 'increasing returns' since the theory is based on insights from economics. Countries remain locked-in onto a given trajectory. Reversals are possible only due to exogenous shocks. Path dependence has been criticized because it provides an overly static view of the world and for its poor treatment of institutional change. The thesis seeks to remedy these shortcomings and presents a case study based on increasing returns and institutional change. It asks whether increasing returns affect institutional reform and, if so, how and why. The case study proposed concerns the trajectory of Italian telecommunications institutions between 1979 and 2007. The trajectory of British telecommunications institutions is used as a benchmark to offer a structured comparison. In answer to the research question, the thesis argues that, between 1979 and 1992, there were increasing returns arising out of the relationships between telecommunications providers and elected politicians. These increasing returns contributed to the failure of proposals for reform, thus confirming that increasing returns keep countries on a steady trajectory. But, between 1992 and 1997 remarkable reforms took place. The thesis shows that new institutions were designed with a view to 'cut off' the opportunities for increasing returns to arise, thus indicating that increasing returns can contribute to institutional reform too. The new institutional trajectory of Italian telecommunications since 1997 continues to be shaped by increasing returns through a complex pattern of reactions and counter reactions by elected politicians. Thus, the thesis makes a contribution to path dependence insofar as it demonstrates that increasing returns can also bring institutional change. New paths can arise without exogenous shocks. In addition, the thesis' findings illustrate that path dependence needs to specify the relationships between increasing returns and actors

    Supramolecular organization of new chiral π-conjugated oligomers: synthesis and spectroscopic study

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    π-Conjugated polymers and oligomers are widely used as organic semiconductors in devices such as field-effect transistors (OFET), light-emitting diodes (OLED) and solar cells (OPV)1; in the last years, a very important role in this field has been played by olygothiophenes2. Their optoelectronic properties (structure of the absorption bands, fluorescence efficiency, charge and exciton transport) depend not only on the chemical nature and the conformation assumed, but also on their supramolecular organization in the solid state. In particular, the introduction of chiral groups can be used to drive their self-assembly. We shall summarize our recent results about the supramolecular aggregation of three new chiral π- conjugated oligomers, consisting of an aromatic central ring (1,4-hydroquinone, benzo[1,2-b:4,5-b′]dithiophene- 4,8-diol, 1,4-diketopyrrolo[3,4-c]pyrrole) functionalized with two (S)-3,7-dimethyl-1-octyl groups and connected to two 2,2'-bithienyl units. In particular, we shall discuss: a) the synthetic route developed for the preparation of these new molecules;b) the characterization of their supramolecular aggregates in solution and of their thin films through optical (UV-VIS, fluorescence) and chiroptical (electronic circular dichroism) spectroscopies, in connection with optical microscopy investigation

    ADDICTIONS SUBSTANCE FREE DURING LIFESPAN

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    The addictions substance free is an umbrella definition comprises internet addiction, sexual addiction, gambling pathological, workholism, videogames and computer addiction. Actually, the technological addictions is frequent in young adolescents. The term Digital Natives indicates the children born in an information system of learning and communication different from that of the generations previous. This temporal range was strongly characterized by growing presence of technological communication toolsin daily life. The effects of hyper-exposition to technological tools tend to create a relational virtuality without a body is born,therefore, already within the family ties and during adolescence he moved to the digital socialization network. The technological object it interacts between the adolescent and the world of peers and adults, becoming the facilitator object that as the psychotropic substance, it conveys new modes of communicatio

    The Impact of the COVID-19 Pandemic on the Practice of Forensic Medicine: An Overview

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    During the COVID-19 pandemic, forensic sciences, on the one hand, contributed to gaining knowledge about different aspects of the pandemic, while on the other hand, forensic professionals were called on to quickly adapt their activities to respond adequately to the changes imposed by the pandemic. This review aims to clarify the state of the art in forensic medicine at the time of COVID-19, discussing the following: the influence of external factors on forensic activities, the impact of autopsy practice on COVID-19 and vice-versa, the persistence of SARS-CoV-2 RNA in post-mortem samples, forensic personnel activities during the SARS-CoV-2 pandemic, the global vaccination program and forensic sciences, forensic undergraduate education during and after the imposed COVID-19 lockdown, and the medico-legal implications in medical malpractice claims during the COVID-19 pandemic. The COVID-19 pandemic has greatly influenced different aspects of human life, and, accordingly, the practical activities of forensic sciences that are defined as multidisciplinary, involving different expertise. Indeed, the activities are very different, including crime scene investigation (CSI), external examination, autopsy, and genetic and toxicological examinations of tissues and/or biological fluids. At the same time, forensic professionals may have direct contact with subjects in life, such as in the case of abuse victims (in some cases involving children), collecting biological samples from suspects, or visiting subjects in the case of physical examinations. In this scenario, forensic professionals are called on to implement methods to prevent the SARS-CoV-2 infection risk, wearing adequate PPE, and working in environments with a reduced risk of infection. Consequently, in the pandemic era, the costs involved for forensic sciences were substantially increased
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