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Superconducting nanowire single-photon detectors (SNSPDs) are receiving the interest of the scientific and industrial communities due to their unparallel high performances in the infrared. However, even though the fabrication process permits the achievement of about 98% efficiency and less than 1 cps dark-count rate, the physical mechanism inducing the detection remains unclear. It is clear however that normal core vortices play a crucial role. In this work we investigate the role of vortices in two-dimensional (2D) molybdenum silicide SNSPDs of different widths covered with an Al layer through the analysis of the switching current distributions from the superconducting to resistive regime, in a wide interval of temperatures from 4.5 K down to 10 mK. This analysis provides the energy scales of different mechanisms that are responsible for fluctuations and dark counts in SNSPDs. We consider two models based on vortices, the unbinding of vortex-Antivortex pairs (VAPs) and vortices hopping over the edge barrier (VH) and we underline the differences among different devices made by different materials. We also estimate the energy scales of similar Nb-Ti-N and NbN devices and compare the results. The lower activation energies obtained for MoSi/Al devices, explain the peculiarity of this material to work at longer wavelengths with a higher quantum detection efficiency.

Trabajo presentado en el SETAC Europe 32nd annual meeting, celebrado en Copenhague (Dinamarca) del 15 al 19 de mayo de 2022., Exotic species such as Procambarus clarkii, Corbicula fluminea, and Leopomis gibbosus have become invasive species in Spain for some decades because they have managed to adapt in Mediterranean wetlands, including the Natural Park of L`Albufera (Valencia). This kind of species, as well as native fauna such as Anodonta sp, may be exposed to a wide range of emerging contaminants and they could be used as bioindicators to assess chemical exposure and pressure on freshwater ecosystem species. In this study, we developed and optimized an extraction method assisted by ultrasound and d-SPE for the simultaneous determination and quantification of different pollutants of emerging concern including 91 pharmaceuticals (PhACs), 11 flame retardants, 21 PFAs, and 55 pesticides. For this purpose, four extraction solvents (1) ACN:iPrOH (3:1) + 0.1%, (2) ACN + 0. 1% F.A, (3) MeOH/H2O (7:3) + 1% F.A (4) MeOH and three cleaning sorbents (1) Z-sep, (2) Z-sep+ (3) Z-sep/C18 were tested. Recovery efficiency tests were performed for each of them and the solvent and sorbent with which the best results were obtained were validated in two of the matrices (Procambarus clarkii and Anodonta sp). To demonstrate the effectiveness of the method, wild samples of the invasive species were collected from L'Albufera Natural Park. Preliminary results indicate the presence of some PhACs such as sulfamethoxazole, citalopram, cotinine, tramadol, and methadone.

We propose a picture for the magnetic properties of superconductor/ferromagnet (S/F) heterostructures based on Nb and permalloy (Py:Fe20Ni80). By measuring the magnetic moment as a function of the temperature in S/F/S trilayers for different thicknesses of the middle F layer, we give evidence of the presence of a magnetic stray field of the F layer. For values of F-layer thickness below a threshold, we establish a correlation between the magnetic measurements of the S/F/S trilayers and the anomalous magnetic dependence of the critical current in S/Insulator/thin superconducting film/F/S (SIsFS) Josephson junctions (JJs). These complementary investigations provide a self-consistent method to fully characterize S/F heterostructures and possibly demonstrate effects arising from the mutual interactions between ferromagnetism and superconductivity. A shift in the Fraunhofer critical current oscillations has been observed in the opposite direction to the one commonly observed in JJs with F barriers, as it has been recently predicted by inverse and electromagnetic proximity theories. This inverse memory effect is relevant for the design of these heterostructures as memory cells and spintronic devices.

The transport properties of a YBa$_2$Cu$_3$O$_{7-��}$ superconducting quantum interference device (SQUID) based on grooved Dayem bridge weak links are studied as a function of temperature: at high temperatures ($60~$K$

We report on the growth and characterization of ultrathin YBa2Cu3O7-? (YBCO) films on MgO (110) substrates, which exhibit superconducting properties at thicknesses down to 3 nm. YBCO nanowires, with thicknesses down to 10 nm and widths down to 65 nm, have also been successfully fabricated. The nanowires protected by a Au capping layer show superconducting properties close to the as-grown films and critical current densities, which are limited by only vortex dynamics. The 10-nm-thick YBCO nanowires without the Au capping present hysteretic current-voltage characteristics, characterized by a voltage switch which drives the nanowires directly from the superconducting to the normal state. We associate such bistability to the presence of localized normal domains within the superconductor. The presence of the voltage switch in ultrathin YBCO nanostructures, characterized by high sheet resistance values and high critical current values, makes our nanowires very attractive devices to engineer single-photon detectors.

"The Josephson effect is a privileged access to the macroscopic quantum nature of superconductors. We review some ideas and experimental techniques on macroscopic quantum decay phenomena occurring in Josephson structures. The attention is mainly addressed to intermediate levels of dissipation which characterize a large majority of low critical currentJosephson devices and are therefore an avoidable consequence of nanotechnology applied more and more to Josephson devices. Phase diffusion phenomena take over thermal activation in some temperature ranges also affecting the transition to macroscopic quantum tunneling, enriching the phase diagram mostly defined by the Josephson energy, the temperature and the level of dissipation."

BACKGROUND: Data on the performance of the tests used to confirm the diagnosis of primary aldosteronism (PA) are limited. OBJECTIVE: To prospectively investigate the accuracy of the saline infusion test (SIT). METHODS: Three hundred and seventeen (26.9%) out of 1125 patients screened in the PAPY study underwent measurement of plasma aldosterone, cortisol and renin activity after infusion of 2 l of isotonic saline intravenously over 4 h. They comprised patients with a baseline aldosterone/renin ratio (ARR) > 40 and one every four patients not fulfilling such criterion. The area under the receiver-operator characteristic curves (AUC) of aldosterone values after SIT was used as a measure of accuracy for diagnosing PA, aldosterone-producing adenoma (APA) or idiopathic hyperaldosteronism (IHA). RESULTS: One hundred and twenty (37.9%) patients had PA that was due to an APA in 46 (38.3%) and to IHA in 74 (61.7%). No untoward effect occurred with the SIT. The AUC (0.811 ± 0.026, 0.878 ± 0.040 and 0.784 ± 0.034 for identification of PA, APA and IHA, respectively) was higher (P < 0.0001) than that under the diagonal. By sensitivity/specificity versus criterion values plot, the best aldosterone cut-off values for identifying APA and IHA were 6.75 and 6.91 ng/dl, respectively. However, even at these optimal cut-offs, sensitivity and specificity were moderate because of values overlapping between patients with and without the disease. Moreover, there were no differences of AUC and aldosterone cut-offs between APA and IHA. CONCLUSION: In a multicenter study the SIT was safe and specific for excluding PA, but had no place for discriminating between an APA and IHA.

Introduction: Several studies have now revealed the direct deleterious effects of excess aldosterone, especially in cardiovascular disease, independent of the usual effect of aldosterone on electrolyte transport [1,2]. These new pathologic findings appear to be direct effects of aldosterone on cardiovascular and other tissues, leading to tissue remodeling and fibrosis. Interestingly, very little attention has been directed toward the kidney and renal damage in primary aldosteronism (PA). In fact, only two publications from the same institution have examined renal function in PA in a limited approach, noting early microalbuminuria when compared to subjects with primary hypertension (PH) [3,4]. In general, studies of renal pathology in PA are lacking. This omission is quite surprising for a disease involving often severe hypertension, and given the new information on the direct effects of aldosterone on tissue fibrosis [5]. Recent knowledge holds that PA is a much more frequent cause of secondary hypertension than previously thought, being as high as 12% of all the hypertensive population, thus involving millions of individuals in the world, further increasing the demand for world organization of screening and evaluation protocols and high-standard special centers [6]. Further information on PA and renal function is mandatory, especially with the newer screening tests to monitor progression of chronic kidney disease (CKD) and the renoprotective features indicating that PA be part of the new tests in nephrology, such as urinary albumin excretion (UAE) and estimated glomerular filtration rate (GFR). The Primary Aldosteronism Prevalence in Italy (PAPY) study is a prospective survey of 1180 consecutive newly diagnosed hypertensive patients referred to specialized hypertension centers in Italy to detect the prevalence of PA and intensely study several of its characteristic features [7]. In this study, 490 subjects were deemed justified for an intensified evaluation for PA, aldosterone-producing adenomas (APA) were found in 4.8% of subjects, and idiopathic hyperaldosteronism (IHA) in 6.4%, for a total incidence of PA of 11.2% in the Italian hypertensive population [7]. The main feature examined for renal function was the UAE, but previous renal function studies also showed serum and urine hyperfiltration and increased microalbuminuria in PA; however, these studies were limited by size and the fact that they studied only patients with APA. As is also well known, increased UAE is a key determinant for cardiovascular damage and endothelial dysfunction in high-risk patients. Thus, UAE would also serve an important role in patients with PA as a marker of their overall cardiovascular burden.