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A haloscope of the QUAX--$a\ensuremath{\gamma}$ experiment composed of an oxygen-free high thermal conductivity-Cu cavity inside an 8.1 T magnet and cooled to $\ensuremath{\sim}200\text{ }\text{ }\mathrm{mK}$ is put in operation for the search of galactic axion with mass ${m}_{a}\ensuremath{\simeq}43\text{ }\text{ }\ensuremath{\mu}\mathrm{eV}$. The power emitted by the resonant cavity is amplified with a Josephson parametric amplifier whose noise fluctuations are at the standard quantum limit. With the data collected in about 1 h at the cavity frequency ${\ensuremath{\nu}}_{c}=10.40176\text{ }\text{ }\mathrm{GHz}$, the experiment reaches the sensitivity necessary for the detection of galactic QCD-axion, setting the 90% confidence level limit to the axion-photon coupling ${g}_{a\ensuremath{\gamma}\ensuremath{\gamma}}l0.766\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}13}\text{ }\text{ }{\mathrm{GeV}}^{\ensuremath{-}1}$.

A ferromagnetic axion haloscope searches for Dark Matter in the form of axions by exploiting their interaction with electronic spins. It is composed of an axion-to-electromagnetic field transducer coupled to a sensitive rf detector. The former is a photon-magnon hybrid system, and the latter is based on a quantum-limited Josephson parametric amplifier. The hybrid system consists of ten 2.1 mm diameter YIG spheres coupled to a single microwave cavity mode by means of a static magnetic field. Our setup is the most sensitive rf spin-magnetometer ever realized. The minimum detectable field is $5.5\times10^{-19}\,$T with 9 h integration time, corresponding to a limit on the axion-electron coupling constant $g_{aee}\le1.7\times10^{-11}$ at 95% CL. The scientific run of our haloscope resulted in the best limit on DM-axions to electron coupling constant in a frequency span of about 120 MHz, corresponding to the axion mass range $42.4$-$43.1\,\mu$eV. This is also the first apparatus to perform an axion mass scanning by changing the static magnetic field., Comment: 4 pages, 4 figures

Nowadays, users’ privacy on the Internet is highly at risk, due to the monetization by advertising companies that support many of the so-called “free” services such as searching or social networking. In fact, several mechanisms are used to monitor users and build detailed profiles to tailor behavioral advertising. Given the increasing use of mobile devices and the increasing revenues from behavioral advertising, large advertising companies are present in this market as well. The increasing use of mobile devices for interacting with the Web and using mobile applications has been also drawing attention to their energy consumption. Several studies have addressed this issue from different point of views, i.e., hardware, software, as well as by analyzing the energy drained by different mobile applications. Our goal in this work is to measure the effectiveness of a methodology that exploits a hardware-based instrumentation to study whether privacy-preserving mechanisms are also able to efficiently reduce communication and computation overhead and, thus, save the battery life of mobile phones with the overall aim of a more sustainable Internet.

We have investigated magnetization cycles of a MgB2 sphere, 4 mm size, at temperatures of 25, 30, and 35 K up to an applied magnetic field μ0H strength of 3 T. Further to magnetization cycles, we also studied the shift of the magnetization peak position as a function of the maximum applied field for field values between the first penetration field and the full penetration field. In this way, we found a shift of the magnetization peak field position toward a saturation value of the applied field, above which no further shift is observed. The shift of the magnetization peak field position has been observed in YBCO thin films, and ascribed to the magnetization trapped in the granular borders of the material. The same mechanisms may be supposed acting in the MgB2 sphere, provided that the saturated peak of the magnetization curve lies in the μ0H < 0 region due to the effect of local field B on the critical current Jc(B) in the spherical geometry. This will show up the shift effect in the H < 0 region. A FEM model with H-formulation has also been implemented, in which the magnetization cycle is taken into account by the power-law E(J) characteristic for the electric field. Our experimental and numerical findings can provide a simple understanding of the observed magnetization cycle in this spherical geometry in saturated and nonsaturated conditions. © 2002-2011 IEEE.

The QUAX proposal studies the interaction of dark matter axions with electrons. As the effect of axions can be described as an effective magnetic field, the signal is a magnetization oscillation of a sample. To detect it, the material is placed in a resonant cavity and polarized with a static magnetic field. Here we describe the operation of such a device, with a resonance frequency of 14 GHz, corresponding to an axion mass ma = 58 μeV. Eventually some recent developments on the resonant cavities design and test are detailed.

In this paper we extensively analyze the magnetization of superconducting bulk cylinders in parallel and transverse magnetic field. We use analytic formulations with different Jc(B) dependencies, and compare the magnetization to 2D and 3D numerical computations for finite geometries with different aspect ratios. This subject is a basic study for understanding the hysteretic losses in a cylindrical geometry, which is the typical geometry occurring in superconducting wires and cables. The shift of the peak of the magnetization cycle is always reproduced by FEM 2D and 3D, as a consequence of considering the local field in the Jc(B). Using different Jc(B) dependencies and different cylinder aspect ratio, we have reproduced the behavior of the magnetization in parallel fields, checking simulation results versus analytical calculations. In this framework we also developed the analytic behavior of the magnetization in parallel fields using the generalized Kim model. Finally, for a cylinder in a perpendicular magnetic configuration, we found that 2D numerical simulations, once suitably scaled, are in agreement to 3D simulations.

Recently the need for fast ramped superconducting magnets in new particle accelerator pushed the development of a new class of NbTi wires able to operate at magnetic ramp rates in the 1T/s range with ac losses that can be handled by ordinary cryogenic systems, e . g . few W/m in long dipoles. During the last decade INFN, in the framework of an international cooperation for the developments of fast ramped superconducting dipoles, launched a wire development program which stepped in three phases of wire design and industrial production. The aim of the program was to develop superconducting wires to be used in the construction of a full size superconducting fast ramped magnet (namely a dipole). This paper describes the main steps towards the development of a low loss superconducting multi filament wire. Three main ideas were the pillars of the development activities: the reduction of the geometrical filament size down to 2 μm, the use of CuMn resistive barriers to reduce the inter filament coupling currents, and the reduction to the minimum allowable value of the twist pitch.

The Normal Zone Propagation Velocity, NZPV, is a widely studied feature in superconducting composite tapes for its technological implications. The stability features and the NZPV values, in different operative conditions, have been investigated in different second generation high critical temperature superconductor tapes. In particular, we focused our studies on tapes, produced by the manufactures SuNAM© and Superpower©. Experimental procedures on the determination of the NZPV, related problems and peculiarities, have been presented and discussed. Data obtained with our experimental configuration, have been analyzed and compared with a phenomenological model.

Axions, originally proposed to solve the strong CP problem of quantum chromodynamics, emerge now as leading candidates of WISP dark matter. The rich phenomenology associated to the light and stable QCD axion can be described as an effective magnetic field that can be experimentally investigated. For the QUAX experiment, dark matter axions are searched by means of their resonant interactions with electronic spins in a magnetized sample. In principle, axion-induced magnetization changes can be detected by embedding a sample in an rf cavity in a static magnetic field. In this work we describe the operation of a prototype ferromagnetic haloscope, with a sensitivity limited by thermal fluctuations and receiver noise. With a preliminary dark matter search, we are able to set an upper limit on the coupling constant of DFSZ axions to electrons $$g_{aee}

The Italian National Institute for Nuclear Physics, within a larger cooperation with other partners, is setting up a new facility at University of Salerno for testing superconducting magnets for accelerators. The setup includes, further to the supercritical He 200 W@4.5 K refrigerator, and the 20 kA power converter, a suitable pair of HTS 20 kA current leads. To keep an optimized system flexibility, the current leads are designed with HTS technology, which allows for reduction of both the conduction heat leak on its cold end, and the Joule heating. In addition to match the cryogenic plant features, the current leads, at current level below 10 kA, are designed to operate with cold He flow provided by the refrigeration plant, thus avoiding LN2 flow. When running the current leads at full current we shall use an additional LN2 bath and evaporation stream to boost the He refrigeration power needed in the copper section of the current leads. This cooling scheme requires a dedicated design of the heat exchangers. In this work we report the numerical analyses of the current leads, concerning only the normal conducting section, to support this refrigeration scheme which have to match two different heat loads.

The Italian Institute for Nuclear Physics is working on the development of fast cycled dipoles for the Facility for Antiproton and Ion Research SIS300 synchrotron at Gesellschaft fur Schwerionenforschung, Darmstadt. In this framework the development of high current and low ac loss superconducting wires is an important step of the R&D. The main technique to attain these features is to develop fine filaments for the strands and to design suitable resistive barriers among filament islands within the strands. In this paper, we study a newly developed wire in terms of critical currents and ac losses. The critical current is obtained from magnetization cycle and direct transport current. The ac loss mechanisms caused by the interfilament electromagnetic coupling is related to the ρet, the transverse resistance between adjacent filaments. We measure ρet through ac susceptibility technique.

More than eighty quadrupole modules, especially designed and fabricated at JNIR in Dubna, will be used at the FAIR facility in Darmstadt. Prior the installation in the new accelerator SIS 100 tunnel, the modules need to be tested by an independent laboratory. The required test have to be the same for all the modules and the answer will be the benchmark for the final decision on accepting or rejecting the module. With this target in mind, a system with as much as possible automatisms will be realized. Three kinds of tests will be performed: mechanical, thermal and electrical. The mechanical test will concern on the search of vacuum leaks, if present, and on the measurement of the limit pressure reached in the vessel. The thermal test will have to check that the various thermometer, scattered inside the modules, will be correctly working and that the heaters are able to deliver the generated heat. The electrical tests will verify the insulation to ground of both the devices and the superconducting coils and bus-bars. All tests will be done in a thermal sequence: at room temperature, at the cryogenic working temperature of 4.5 K, and finally at room temperature again.

Recently, the study of complex networks led to the analysis of the so-called scale-free models in statistical mechanics. This study has increased its importance, thanks to the wide range of applications in numerous physical contexts; for example, one important question is to understand the behavior of various models on such networks. We start first by investigating the Ising model in the mean field approximation and on scale-free networks, studying especially the Ising model with annealed dilution and Clock model, with particular attention devoted to focusing on similarities between the mean field approximations with or without scale-free statistics. A particular emphasis is given to the possible practical applications of these results in other disciplines such as medicine and social science.

We have investigated the frequency dependence of the magnetic losses of different 2 G commercial REBCO coated-conductor tapes in the low frequency range ∼1-10 mHz of applied magnetic field at 5 and 77 K. We explored high field range, well above the penetration field, with fields applied perpendicularly to the flat surface. We found that the in-field hysteresis losses increase with increasing frequencies in all the investigated high-temperature superconductor (HTS) tapes, following a power-law dependence. An electromagnetic 2D finite element method model, based on H-formulation, has also been implemented, in which the frequency dependence of the hysteretic loss is computed taking into account the measured power-law E(J) characteristic for the electric field, and the experimental J c(B). Experimental and numerical findings are in very good agreement, so an extrapolation to higher ramp rate values is possible, thus providing a useful basis for the assessment of the hysteresis losses in fusion and accelerator HTS magnets. © 2018 IOP Publishing Ltd.

Bovine Somatotropin (bST) is a peptide hormone secreted by the anterior pituitary gland and its recombinant form (rbST) is used for artificially boosting milk yield in cows. Identification of rbST is difficult in that there is little difference from the pituitary bST (pbST). In this work, we further studied the possibility of immunologically discriminating between rbST and pbST. With this purpose, we produced mouse monoclonal antibodies using, as antigen, a peptide mimicking the N-terminus of rbST from Monsanto (rbST-M) conjugated to keyhole limpet haemocyanin (KLH) and polyclonal antibodies in rabbits immunized with the whole bST or rbST-M. Hence, we developed a sandwich ELISA with the obtained antibodies for detection and quantification of bST in serum and compared its performance on the two worldwide commercialized rbSTs: rbST-M and rbST from LG Life Science (rbST-LG). The lowest detection limit of the assay was 0·05 ng/ml for rbST-M, 0·10 ng/ml for rbST-LG and 0·15 ng/ml for pbST. Furthermore, the assay showed the capability to amplify the signal in the presence of rbSTs, recognizing more efficiently rbST-M and rbST-LG than pbST (ECn pbST/ECn rbST: 3 and 1·6 respectively). Its employment for measuring bST levels in sera from bovines administered with rbST LG allowed us to detect exceptional values due to the treatment itself and probably further increased as a consequence of the higher affinity for rbSTs of our monoclonal antibody.

The evolution of the structural properties of ${A}_{1\ensuremath{-}x}{A}_{x}^{\ensuremath{'}}{\mathrm{MnO}}_{3}$ was determined as a function of temperature, average $A$-site radius $〈{r}_{A}〉,$ and applied pressure for the ``optimal'' doping range $x=0.25,$ 0.30, by using high-resolution neutron powder diffraction. The metal-insulator transition, which can be induced both as a function of temperature and of $〈{r}_{A}〉,$ was found to be accompanied by significant structural changes. Both the paramagnetic charge-localized phase, which exists at high temperatures for all values of $〈{r}_{A}〉,$ and the spin-canted ferromagnetic charge-ordered phase, which is found at low temperatures for low values of $〈{r}_{A}〉,$ are characterized by large metric distortions of the ${\mathrm{MnO}}_{6}$ octahedra. These structural distortions are mainly incoherent with respect to the space-group symmetry, with a significant coherent component only at low $〈{r}_{A}〉.$ These distortions decrease abruptly at the transition into the ferromagnetic metal phase. These observations are consistent with the hypothesis that, in the insulating phases, lattice distortions of the Jahn-Teller type, in addition to spin scattering, provide a charge-localization mechanism. The evolution of the average structural parameters indicates that the variation of the electronic bandwidth is the driving force for the evolution of the insulator-to-metal transition at ${T}_{C}$ as a function of ``chemical'' and applied pressure.

This paper aims at investigating the integrated satellite/terrestrial interactive e-health system, which has been developed within the framework of the European Space Agency (ESA) project TElemedicine Services for HEALTH (TESHEALTH) in collaboration among industry, academia, and hospitals. The implementation of a secure, scalable and flexible heterogeneous network capable of providing the appropriate infrastructure, is analysed, focusing on the end to end QoS solution, that satisfies the quality level required by the telemedicine applications. Moreover the developed interactive Service Platform, which aims at sharing health information among the different applications and services (Self-Care and Assisted Services) and includes realtime audio and video interactions among patients, specialists and health service providers, is described.

We have measured critical temperatures and upper critical magnetic fields as a function of the ferromagnetic layer thickness, ${d}_{F}$, in two different superconductor(S)/ferromagnet(F)/superconductor(S) triple layers: $\text{Nb}/{\text{Cu}}_{0.41}{\text{Ni}}_{0.59}/\text{Nb}$ and $\text{Nb}/{\text{Pd}}_{0.81}{\text{Ni}}_{0.19}/\text{Nb}$. We vary ${d}_{F}$ from the 0-phase coupling to the $\ensuremath{\pi}$-phase coupling regime and find strong nonmonotonic behavior of the anisotropy coefficient ${\ensuremath{\gamma}}_{GL}={H}_{c2\ensuremath{\parallel}}(0)/{H}_{c2\ensuremath{\perp}}(0)$ characterized by an initial increase, a peak, and a subsequent decrease. The peak is a manifestation of the small coupling which exists around the $0\text{\ensuremath{-}}\ensuremath{\pi}$ transition and it is qualitatively in agreement with recent theoretical predictions [B. Krunavakarn and S. Yoksan, Physica C 440, 25 (2006)] which includes the effect of the different interface transparencies of the two systems. The experimental results demonstrate that the occurrence of the $\ensuremath{\pi}$ phase strongly influences the transport properties of S/F/S systems in external fields.

DigesTip is a new device for in-solution protein digestion, based on a patent pending technology, able to immobilize enzymes (trypsin, in this case) on a solid surface, keeping their activity preserved. DigesTip is a standard pipette tip, usable both by human and by robots. Its main performances are: very short digestion time (1 min) and usability with low protein sample concentrations (5 microg/mL). DigesTip obtains a clear signal in MS measurements and its usage rules out several preparative steps.

Guidi, A., Castigliego, L., Iannone, G., Armani, A. and Gianfaldoni, D., 2007. An immunoenzymatic method to measure igf-1 in milk. Veterinary Research Communications, 31(Suppl. 1), 373–376

Electrical and magnetic properties of sputtered ${\mathrm{Pd}}_{86}{\mathrm{Ni}}_{14}$, ${\mathrm{Cu}}_{46}{\mathrm{Ni}}_{54}$, and ${\mathrm{Cu}}_{42}{\mathrm{Ni}}_{58}$ thin films have been investigated. ${\mathrm{Pd}}_{86}{\mathrm{Ni}}_{14}$ shows clear ferromagnetic properties even if magnetic clusters of $4.6{\ensuremath{\mu}}_{B}$ are observed above the Curie-Weiss temperature, ${T}_{\mathrm{CW}}$. Different magnetic properties are observed in $\mathrm{CuNi}$ alloys. Below ${T}_{\mathrm{CW}}$, the field cooling susceptibility increases quasilinearly, while very large magnetic clusters, up to $10\ensuremath{-}12{\ensuremath{\mu}}_{B}$, are observed above ${T}_{\mathrm{CW}}$. The temperature behavior of the resistivity of the thin films of the three alloys shows some common features. In particular, after a minimum the resistivity increases, probably due to the scattering of conduction electrons with Ni clusters. The temperature at which the minimum appears does not seem to depend on the host metal (Pd or Cu) and on the Ni concentration. These magnetic clusters affect the resistance behavior in the temperature range where the alloys are paramagnetic or close to their magnetic transition.

The use of FEM models to simulate the Bean critical state is used in two particular geometries: the disk and the sphere exposed to a uniform magnetic field. Two FEM approaches have been used, the Adaptive Resistivity Algorithm under the ANSYS framework, and the H-Formulation using the COMSOL software. In this work, the validity of these methods to solve two-dimensional and three-dimensional models is proven through the comparison to the existing theories. In order to reproduce the experimental magnetization cycles, the critical current density dependence on magnetic field has been derived from measurements in YBCO thin disk at 65 K and a Nb spherical samples at 6.0 K. While the YBCO disk critical state is well reproduced by our models, the Nb sample shows more complicated response which cannot be simulated just considering a critical state model.

Extensive applications of YBa2Cu3O7-x (YBCO) tapes require a comprehensive knowledge of their behavior in every possible operating condition. In this paper, the thermal stability behavior of a conduction-cooled pancake coil wound with commercial YBCO coated conductors is reported from both the experimental and numerical point of view. The coil stability against heat disturbances is studied in terms of minimum quench energy and normal zone propagation velocity (NZPV) for different values of the coil currents at different temperatures. The quench dynamics of the tape is compared between experiment and the numerical analysis, obtaining a reasonable agreement for voltage traces, NZPV, and temperatures. The model allows a wide range of case studies that can be used to suggest appropriate solutions for the design of detection and protection systems.

Following the introduction of a phenomenological cellular automata (CA) model capable to reproduce city growth and urban sprawl, we develop a toy model simulation considering a realistic framework. The main characteristic of our approach is an evolution algorithm based on inhabitants preferences. The control of grown cells is obtained by means of suitable functions which depend on the initial condition of the simulation. New born urban settlements are achieved by means of a logistic evolution of the urban pattern while urban sprawl is controlled by means of the population evolution function. In order to compare model results with a realistic urban framework we have considered, as the area of study, the island of Capri (Italy) in the Mediterranean Sea. Two different phases of the urban evolution on the island have been taken into account: a new born initial growth as induced by geographic suitability and the simulation of urban spread after 1943 induced by the population evolution after this date.

A systematic study of yttrium substitution for calcium in the high-temperature superconductor Bi2Sr2CaCu2O8 compound has been performed. The samples of Bi2Sr2YxCa1−xCu2O8 have been prepared by the sintering standard procedure using oxides and carbonates as precursors, weighted to obtain the nominal composition with 0≤x≤1. The real stoichiometric composition of the pellets and uniformity of the samples has been verified by EDS analysis. The grain dimension (≈1 μm) and the good pellet compactness have been established by SEM morphologic observation. By X-ray diffraction analysis the crystalline structure of orthorhombic type has been established. By increasing the yttrium concentration the resistivity dependence on temperature goes from metallic to insulating behaviour. For the superconductive samples Tc decreases for increasing doping percentage. «Thick» films on MgO substrates of Bi2Sr2CaCu2O8 have been obtained by melting-quenching-annealing procedure. These films showed critical temperatures higher than the pellets.

We investigate some intriguing consequences of characterizing dark energy by the so- called scale-free statistics in a flat Friedman-Robertson-Walker cosmology. We adopt a toy model, derived from a power law distribution, being P (k) ∼ k �γ ,w ith 2

We have investigated the proximity effect in Nb/Cu0.42Ni0.58/Nb trilayers with different thicknesses of the ferromagnetic layer, dCuNi, in external magnetic fields. From the temperature dependence of both parallel and perpendicular critical magnetic fields we found that the behavior of the anisotropy coefficient γGL(dCuNi) presents a maximum in the region where the oscillating character of the superconducting order parameter is expected.

Nb/Pd0.81Ni0.19 hybrids have been investigated regarding their finiteness. Experimental results revealed the oscillating behavior of the superconducting critical temperature as a function of the ferromagnetic thickness dF in bilayers, as well as the dependence of the width of the superconducting transition on the number of bilayers Nbil in multilayers. Using the material parameters obtained from the study of the bilayers, we built the spatial distributions of the anomalous wave functions and we established the multimode character of the superconducting transition in S/F multilayers. The characteristic features of this transition depend on the number of bilayers, odd or even. For the samples with odd Nbil the multimode states are more pronounced due to the instability of the nonzeroes solution for the anomalous wave function.

A study was performed to delineate bST and IGF-1 variation, over a whole lactation, in cows treated with a nowadays widely commercialised but little studied sustained release formulation of recombinant bST. Total bST levels were found to be exceptionally high in the first days after administration, but decreased rapidly in the second week after injection. The increase in the IGF-1 serum concentration was significant for almost the entire biweekly cycle. Based on this study, the peaks of ST (often above 100 ng/ml) are considered particularly unlikely to be found in non-treated bovines, even under pathological conditions, especially when detected in a number of animals within a herd. Notwithstanding the great heterogeneity of results on this topic, these data suggest that tests against fraud involving the use of rbST in dairy products may be regarded as a feasible possibility.

The color of food, especially meat and meat products, is a parameter that strongly influences consumer choice. In Italy, repeated cases of darkening in deboned thigh meat of male turkeys packaged in modified atmosphere (MAP; 80% 02, 20% CO2) have been reported. The pH, lipid oxidation (TBARS), heme proteins, and iron content were investigated in MAP samples of turkey males, females, and in oxygen-permeable film-packaged males. Furthermore, the absorbance spectrum (400 to 700 nm) of the meat extracts was analyzed to better delineate the evolution and characteristics of the darkening process. Results showed that darkening occurred only in males with higher content of total iron, independently of the content of heme proteins, which differs only between males and females. Furthermore, pH was higher in muscles taken as controls, with respect to muscles involved in the darkening, as well as in females. Finally, TBARS values were found to be higher in darkened regions than in not darkened ones, as well as in MAP samples with respect to oxygen-permeable film-packaged samples. These findings suggest that darkening occurrence might depend on kind of muscle, sex, and individual characteristics of the animals raised under the same breeding conditions.