117 research outputs found

    Interface-induced heavy-hole/light-hole splitting of acceptors in silicon

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    The energy spectrum of spin-orbit coupled states of individual sub-surface boron acceptor dopants in silicon have been investigated using scanning tunneling spectroscopy (STS) at cryogenic temperatures. The spatially resolved tunnel spectra show two resonances which we ascribe to the heavy- and light-hole Kramers doublets. This type of broken degeneracy has recently been argued to be advantageous for the lifetime of acceptor-based qubits [Phys. Rev. B 88 064308 (2013)]. The depth dependent energy splitting between the heavy- and light-hole Kramers doublets is consistent with tight binding calculations, and is in excess of 1 meV for all acceptors within the experimentally accessible depth range (< 2 nm from the surface). These results will aid the development of tunable acceptor-based qubits in silicon with long coherence times and the possibility for electrical manipulation

    Certification of spin-based quantum simulators

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    Quantum simulators are engineered devices controllably designed to emulate complex and classically intractable quantum systems. A key challenge is to certify whether the simulator truly mimics the Hamiltonian of interest. This certification step requires the comparison of a simulator's output to a known answer, which is usually limited to small systems due to the exponential scaling of the Hilbert space. Here, in the context of Fermi-Hubbard spin-based analog simulators, we propose a modular many-body spin to charge conversion scheme that scales linearly with both the system size and the number of low-energy eigenstates to discriminate. Our protocol is based on the global charge state measurement of a 1D spin chain performed at different detuning potentials along the chain. In the context of semiconductor-based systems, we identify realistic conditions for detuning the chain adiabatically to avoid state mixing while preserving charge coherence. Large simulators with vanishing energy gaps, including 2D arrays, can be certified block-by-block with a number of measurements scaling only linearly with the system size

    Hepatic epidermoid cyst

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    open6noWe describe the extraordinary finding of a hepatic epidermoid cyst in a 5-year-old patient, treated successfully with laparoscopic deroofing and mucosal stripping. The pathologic examination revealed a cyst with the same features of a true epithelial splenic cyst whose origin is still controversial, even though a coelomic derivation is the most accredited hypothesis. A cyst in this anatomic district with such characteristics has never been described in existent literature.openDi Salvo, N.*; Libri, M.; Gargano, T.; Salfi N; Ruggeri, G.; Lima, M.Di Salvo, N.*; Libri, M.; Gargano, T.; Salfi N; Ruggeri, G.; Lima, M

    Gender-related time course of sleep disturbances and psychological symptoms during the COVID-19 lockdown: a longitudinal study on the Italian population

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    Italy was the first western hotspot of the COVID-19 pandemic. In order to contain the spread of the virus, the Italian Government imposed home confinement to the entire population for almost two months. The present study is the first large-scale longitudinal report of the sleep and mental health changes during the prolonged lockdown due to the COVID-19 outbreak. We focused on the gendered vulnerability in a sample of the Italian population since cross-sectional research identified women to be more at-risk than men during this unprecedented situation. A total of 2701 individuals (mean age ± standard deviation, 32.37 ± 11.62; range, 18–82) participated in a web-based longitudinal survey consisting of two measurements. Participants were first-time recruited on social networks and via telephone messages through a snowball sampling and tested during the third week of the lockdown period. Subsequently, a follow-up evaluation was carried out during the seventh week of restraining measures. The survey assessed sleep quality, insomnia and depression symptoms, perceived stress, and anxiety, using the following questionnaires: the Pittsburgh Sleep Quality Index, the Insomnia Severity Index, the Beck Depression Inventory-second edition, the 10-item Perceived Stress Scale, and the State-Anxiety Inventory. Female gender showed the worst condition for all the examined dimensions in both the assessments. Nevertheless, at the follow-up women reported a reduction in insomnia and depression severity symptoms, perceived stress, and anxiety. On the other hand, male participants showed a worsening of sleep quality, insomnia symptoms, and perceived stress. Consequently, the gender prevalence gap of clinical conditions such as insomnia and depression was largely reduced under lockdown. Our investigation pointed to a different time course of sleep and mental health between genders during the home confinement period. Women seemed to show greater long-term resilience during the lockdown. Meanwhile, the male gender emerges as the most vulnerable category to the extension of the restraining measures. Our results suggest that there is no “weaker gender” after a prolonged lockdown. Indeed, the Italian population transversely presented signs of psychological suffering and significant sleep disturbances after the protracted and stressful lockdown period due to the COVID-19 pandemic

    Autochthonous cases of mucosal leishmaniasis in Northeastern Italy: clinical management and novel treatment approaches

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    Mucosal leishmaniasis (ML) is a rare clinical variant of tegumentary leishmaniasis in Mediterranean Europe. Here we report on three autochthonous cases of head and neck ML in patients living in Northeastern Italy. Patients presented with non-specific, long-standing symptoms of upper respiratory tract involvement, mimicking other diseases. Parasitological diagnosis was reached by histopathology, immunohistochemistry and molecular biology on tissue specimens. Leishmania infantum was identified by molecular typing in all three cases. All patients reached a complete remission with protracted multivalent antileishmanial drugs; in one case, a novel approach of combined medical and endoscopic surgical treatment was carried out. High clinical suspicion led to a prompt diagnosis and deployment of a multivalent treatment. ML should be considered in the differential diagnosis of nasal, oral, and pharyngolaryngeal lesions in endemic areas. A prompt diagnosis is mandatory to establish a correct management; different antileishmanial medications as well as endoscopic surgical options may be required to reach a complete remission

    Antiandrogens as Therapies for COVID-19: A Systematic Review.

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    In 2019, the breakthrough of the coronavirus 2 disease (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), represented one of the major issues of our recent history. Different drugs have been tested to rapidly find effective anti-viral treatments and, among these, antiandrogens have been suggested to play a role in mediating SARS-CoV-2 infection. Considering the high heterogeneity of studies on this topic, we decided to review the current literature. We performed a systematic review according to PRISMA guidelines. A search strategy was conducted on PUBMED and Medline. Only original articles published from March 2020 to 31 August 2023 investigating the possible protective role of antiandrogens were included. In vitro or preclinical studies and reports not in the English language were excluded. The main objective was to investigate how antiandrogens may interfere with COVID-19 outcomes. Among 1755 records, we selected 31 studies, the majority of which consisted of retrospective clinical data collections and of randomized clinical trials during the first and second wave of the COVID-19 pandemic. In conclusion, we can state that antiandrogens do not seem to protect individuals from SARS-CoV-2 infection and COVID-19 severity and, thus, their use should not be encouraged in this field

    Charge-Insensitive Single-Atom Spin-Orbit Qubit in Silicon

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    High fidelity entanglement of an on-chip array of spin qubits poses many challenges. Spin-orbit coupling (SOC) can ease some of these challenges by enabling long-ranged entanglement via electric dipole-dipole interactions, microwave photons, or phonons. However, SOC exposes conventional spin qubits to decoherence from electrical noise. Here we propose an acceptor-based spin-orbit qubit in silicon offering long-range entanglement at a sweet spot where the qubit is protected from electrical noise. The qubit relies on quadrupolar SOC with the interface and gate potentials. As required for surface codes, 10510^5 electrically mediated single-qubit and 10410^4 dipole-dipole mediated two-qubit gates are possible in the predicted spin lifetime. Moreover, circuit quantum electrodynamics with single spins is feasible, including dispersive readout, cavity-mediated entanglement, and spin-photon entanglement. An industrially relevant silicon-based platform is employed.Comment: 4 pages, 2 figure
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