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An in-depth analysis of Abrikosov vortex dynamics and flux-flow instabilities was performed in NbRe/Au and NbRe/Py bilayers to compare superconducting/normal metal (S/N) and superconducting/ferromagnetic (S/F) heterostructures based on the same superconducting layer. The heterostructures, fabricated by sputtering, were characterized through electrical transport measurements. The I – V characteristics show that, in the NbRe/Py bilayer, vortices reach higher critical velocities than those observed in the NbRe/Au structure. The analysis of the flux-flow instability within the Larkin–Ovchinnikov framework allows one to extract the quasiparticle energy relaxation time. For external magnetic field values for which edge barrier pinning is dominant and thermal effects are negligible, the relaxation times are about 150 ps and 24 ps for NbRe/Au and NbRe/Py bilayers, respectively. These results indicate that NbRe/Py bilayers, having a relaxation time one order of magnitude smaller than values reported in NbRe microbridges, have great potential for the realization of devices where fast relaxation processes are required.

We performed a detailed investigation of the superconducting properties of polycrystalline Pr1−xCexPt4Ge12 pellets. We report the effect of Ce substitution, for x = 0.07, on magnetic field phase diagram H-T. We demonstrate that the upper critical field is well described by the Ginzburg–Landau model and that the irreversibility field line has a scaling behaviour similar to cuprates. We also show that for magnetic fields lower than 0.4 T, the activation energy follows a power law of the type H−1/2, suggesting a collective pinning regime with a quasi-2D character for the Ce-doped compound with x = 0.07. Furthermore, by means of a point contact Andreev reflection spectroscopy setup, we formed metal/superconductor nano-junctions as small as tens of nanometers on the PrPt4Ge12 parent compound (x = 0). Experimental results showed a wide variety of conductance features appearing in the dI/dV vs. V spectra, all explained in terms of a modified Blonder–Tinkham–Klapwijk model considering a superconducting order parameter with nodal directions as well as sign change in the momentum space for the sample with x = 0. The numerical simulations of the conductance spectra also demonstrate that s-wave pairing and anisotropic s-waves are unsuitable for reproducing experimental data obtained at low temperature on the un-doped compound. Interestingly, we show that the polycrystalline nature of the superconducting PrPt4Ge12 sample can favour the formation of an inter-grain Josephson junction in series with the point contact junction in this kind of experiments.

Point-contact spectroscopy was performed on bulk samples of electron-doped high temperature superconductor Nd2−xCexCuO4−δ. The samples were characterized using X-ray diffraction and scanning electron microscopy equipped with a wavelength-dispersive spectrometer and an electron backscatter diffraction detector. Samples with Ce content x = 0.15 showed the absence of spurious phases and randomly oriented grains, most of which had dimensions of approximately 220 µm2. The low-bias spectra in the tunneling regime, i.e., high-transparency interface, exhibited a gap feature at about ±5 meV and no zero-bias conductance, despite the random oriented grains investigated within our bulk samples, consistent with most of the literature data on oriented samples. High-bias conductance was also measured in order to obtain information on the properties of the barrier. A V-shape was observed in some cases, instead of the parabolic behavior expected for tunnel junctions.

We performed a detailed investigation of the superconducting properties of polycrystalline Pr Ce Pt Ge pellets. We report the effect of Ce substitution, for x = 0.07, on magnetic field phase diagram H-T. We demonstrate that the upper critical field is well described by the Ginzburg-Landau model and that the irreversibility field line has a scaling behaviour similar to cuprates. We also show that for magnetic fields lower than 0.4 T, the activation energy follows a power law of the type ? , suggesting a collective pinning regime with a quasi-2D character for the Ce-doped compound with x = 0.07. Furthermore, by means of a point contact Andreev reflection spectroscopy setup, we formed metal/superconductor nano-junctions as small as tens of nanometers on the PrPt Ge parent compound (x = 0). Experimental results showed a wide variety of conductance features appearing in the dI/dV vs. V spectra, all explained in terms of a modified Blonder-Tinkham-Klapwijk model considering a superconducting order parameter with nodal directions as well as sign change in the momentum space for the sample with x = 0. The numerical simulations of the conductance spectra also demonstrate that s-wave pairing and anisotropic s-waves are unsuitable for reproducing experimental data obtained at low temperature on the un-doped compound. Interestingly, we show that the polycrystalline nature of the superconducting PrPt Ge sample can favour the formation of an inter-grain Josephson junction in series with the point contact junction in this kind of experiments.

The stability against quench is one of the main issue to be pursued in a superconducting material which should be able to perform at very high levels of current densities. Here we focus on the connection between the critical current \\(I_c\\) and the quenching current \\(I^*\\) associated to the so-called flux-flow instability phenomenon, which sets in as an abrupt transition from the flux flow state to the normal state. To this purpose, we analyze several current-voltage characteristics of three types of iron-based thin films, acquired at different temperature and applied magnetic field values. For these samples, we discuss the impact of a possible coexistence of intrinsic electronic mechanisms and extrinsic thermal effects on the quenching current dependence upon the applied magnetic field. The differences between the quenching current and the critical current are reported also in the case of predominant intrinsic mechanisms. Carrying out a comparison with high-temperature cuprate superconductors, we suggest which material can be the best trade-off between maximum operating temperature, higher upper critical field and stability under high current bias.

The improvement in the fabrication techniques of iron-based superconductors have made these materials real competitors of high temperature superconductors and MgB\\(_2\\). In particular, iron-chalcogenides have proved to be the most promising for the realization of high current carrying tapes. But their use on a large scale cannot be achieved without the understanding of the current stability mechanisms in these compounds. Indeed, we have recently observed the presence of flux flow instabilities features in Fe(Se,Te) thin films grown on CaF\\(_2\\). Here we present the results of current-voltage characterizations at different temperatures and applied magnetic fields on Fe(Se,Te) microbridges grown on CaF\\(_2\\). These results will be analyzed from the point of view of the most validated models with the aim to identify the nature of the flux flow instabilities features (i.e., thermal or electronic), in order to give a further advance to the high current carrying capability of iron-chalcogenide superconductors.

Nd\\(_{2-x}\\)Ce\\(_x\\)CuO\\(_{4\\pm\\delta}\\) (NCCO) epitaxial thin films have been deposited on (100) SrTiO\\(_3\\) substrates by DC sputtering technique in different atmosphere. The as-grown samples show different dependence of the in-plane resistivity at low temperature, when they are grown in pure argon atmosphere or in oxygen. Moreover, an unusual behaviour is also found when transport takes place in the presence of an external magnetic field. It is commonly accepted that the higher anisotropic properties of NCCO crystalline cell with respect to the hole doped YBCO and LSCO and the electric conduction mainly confined in the CuO\\(_2\\) plane, strongly support the two-dimensional (2D) character of the current transport in this system. Results on the temperature dependence of the resistance, as well as on the magnetoresistance and the Hall coefficient, obtained on epitaxial NCCO thin films in the over-doped region (\\(x\\ge0.15\\)) of the phase diagram are presented and discussed.

Oncolytic herpes simplex viruses are proving to be effective in clinical trials against a number of cancers. Here, R-115, an oncolytic herpes simplex virus retargeted to human erbB-2, fully virulent in its target cells, and armed with murine interleukin-12 was evaluated in a murine model of glioblastoma. We show that a single R-115 injection in established tumors resulted, in about 30% of animals, in the complete eradication of the tumor, otherwise invariably lethal. The treatment also induced a significant improvement in the overall median survival time of mice and a resistance to recurrence from the same neoplasia. Such a high degree of protection was unprecedented; it was not observed before following treatments with the commonly used, mutated/attenuated oncolytic viruses. This is the first study providing the evidence of benefits offered by a fully virulent, retargeted, and armed herpes simplex virus in the treatment of glioblastoma and paves the way for clinical translation.

Background and Objectives: Dry eye disease (DED) is a multifactorial ocular surface disease that markedly diminishes quality of life. Although diabetes mellitus is well-known for its retinal consequences, anterior segment symptoms including dry eye disease are often overlooked. Chronic hyperglycemia causes metabolic, neurovascular, and immunological changes that undermine tear film stability, corneal innervation, and ocular surface integrity. This review seeks to consolidate existing knowledge regarding the concealed impacts of diabetes on ocular surface homeostasis, highlighting processes, diagnostic difficulties, and treatment prospects. Materials and Methods: A narrative review of the literature was performed by searching PubMed for publications from January 2020 to July 2025 using the terms “diabetic dry eye,” “hyperglycemia AND ocular surface,” “tear proteomics AND diabetes,” “corneal nerves AND diabetes,” and “neurotrophic keratitis.” Eligible studies were experimental research, clinical trials, and translational investigations concerning tear film function, corneal neuropathy, inflammatory indicators, or lacrimal gland dysfunction in diabetes. The exclusion criteria were non-English language, lack of primary data, and inadequate methodological description. Results: Hyperglycemia compromises lacrimal gland functionality, modifies lipid secretion from Meibomian glands, and diminishes corneal nerve density, resulting in neurotrophic deficits. Inflammatory cytokines and oxidative stress compromise epithelial integrity, but proteome alterations in tears serve as sensitive indicators of disease. Diagnosis is impeded by corneal hypoesthesia, resulting in a disconnection between symptoms and findings. Progress in imaging, proteomics, and artificial intelligence may facilitate earlier detection and improved risk assessment. Novel therapeutics, such as neurotrophic drugs, antioxidants, and customized anti-inflammatory approaches, show promise but remain under clinical evaluation. Conclusions: Diabetes-related dry eye disease is a multifaceted and underappreciated condition influenced by systemic metabolic dysfunction. The ocular surface may act as an initial indicator for systemic disease load. Narrative synthesis emphasizes the necessity for customized diagnostic instruments, individualized treatment approaches, and collaborative management. Reconceptualizing diabetic dry eye disease within the context of systemic metabolic care presents prospects for precision medicine strategies that enhance both ocular and systemic results.

Background: This study compared the performance of a Head-mounted Virtual Reality Perimeter (HVRP) with the Humphrey Field Analyzer (HFA), the standard in automated perimetry. The HFA is the established standard for automated perimetry but is constrained by lengthy testing, bulky equipment, and limited patient comfort. Comparative data on newer head-mounted virtual reality perimeters are limited, leaving uncertainty about their clinical reliability and potential advantages. Aim: The aim was to evaluate parameters such as visual field outcomes, portability, patient comfort, eye tracking, and usability. Methods: Participants underwent testing with both devices, assessing metrics like mean deviation (MD), pattern standard deviation (PSD), and duration. Results: The HVRP demonstrated small but statistically significant differences in MD and PSD compared to the HFA, while maintaining a consistent trend across participants. MD values were slightly more negative for HFA than HVRP (average difference −0.60 dB, p = 0.0006), while pattern standard deviation was marginally higher with HFA (average difference 0.38 dB, p = 0.00018). Although statistically significant, these differences were small in magnitude and do not undermine the clinical utility or reproducibility of the device. Notably, HVRP showed markedly shorter testing times with HVRP (7.15 vs. 18.11 min, mean difference 10.96 min, p < 0.0001). Its lightweight, portable design allowed for bedside and home testing, enhancing accessibility for pediatric, geriatric, and mobility-impaired patients. Participants reported greater comfort due to the headset design, which eliminated the need for chin rests. The device also offers potential for AI integration and remote data analysis. Conclusions: The HVRP proved to be a reliable, user-friendly alternative to traditional perimetry. Its advantages in comfort, portability, and test efficiency support its use in both clinical settings and remote screening programs for visual field assessment. Its portability and user-friendly design support broader use in clinical practice and expand possibilities for bedside assessment, home monitoring, and remote screening, particularly in populations with limited access to conventional perimetry.