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Galactic gamma-ray diffuse emission (GDE) is emitted by cosmic rays (CRs), ultra-relativistic protons, and electrons, interacting with gas and electromagnetic radiation fields in the interstellar medium. Here we present the analysis of teraelectronvolt diffuse emission from a region of the Galactic plane over the range in longitude of l ∈ [43°, 73°], using data collected with the High Altitude Water Cherenkov (HAWC) detector. Spectral, longitudinal, and latitudinal distributions of the teraelectronvolt diffuse emission are shown. The radiation spectrum is compatible with the spectrum of the emission arising from a CR population with an index similar to that of the observed CRs. When comparing with the DRAGON base model , the HAWC GDE flux is higher by about a factor of 2. Unresolved sources such as pulsar wind nebulae and teraelectronvolt halos could explain the excess emission. Finally, deviations of the Galactic CR flux from the locally measured CR flux may additionally explain the difference between the predicted and measured diffuse fluxes.

Theories predict teleportation of phase-coherent single electrons through a topological superconducting island. Here, the authors report persistent Coulomb blockade conductance peaks due to coherent transport of single electrons through patterned InAs-Al islands embedded in an Aharonov-Bohm interferometer.

Majorana zero modes--quasiparticle states localized at the boundaries of topological superconductors--are expected to be ideal building blocks for fault-tolerant quantum computing.sup.1,2. Several observations of zero-bias conductance peaks measured by tunnelling spectroscopy above a critical magnetic field have been reported as experimental indications of Majorana zero modes in superconductor-semiconductor nanowires.sup.3-8. On the other hand, two-dimensional systems offer the alternative approach of confining Majorana channels within planar Josephson junctions, in which the phase difference [phi] between the superconducting leads represents an additional tuning knob that is predicted to drive the system into the topological phase at lower magnetic fields than for a system without phase bias.sup.9,10. Here we report the observation of phase-dependent zero-bias conductance peaks measured by tunnelling spectroscopy at the end of Josephson junctions realized on a heterostructure consisting of aluminium on indium arsenide. Biasing the junction to [phi] [almost equal to] [pi] reduces the critical field at which the zero-bias peak appears, with respect to [phi] = 0. The phase and magnetic-field dependence of the zero-energy states is consistent with a model of Majorana zero modes in finite-size Josephson junctions. As well as providing experimental evidence of phase-tuned topological superconductivity, our devices are compatible with superconducting quantum electrodynamics architectures.sup.11 and are scalable to the complex geometries needed for topological quantum computing.sup.9,12,13. Evidence is found for phase-tunable Majorana zero modes in scalable two-dimensional Josephson junctions produced by top-down fabrication., Author(s): Antonio Fornieri [sup.1] , Alexander M. Whiticar [sup.1] , F. Setiawan [sup.2] , Elías Portolés [sup.1] , Asbjørn C. C. Drachmann [sup.1] , Anna Keselman [sup.3] , Sergei Gronin [...]

La cardiomiopatía diabética es una entidad que se origina a partir de una complicación microvascular de la diabetes mellitus tipo 2, la cual se desarrolla por la sinergia de varios elementos metabólicos generados por la hiperglicemia crónica y oxidación ácidos grasos libres que causan un impacto perjudicial por diferentes vías bioquímicas a nivel del miocardio provocando cambios estructurales y funcionales, como consecuencia generan disfunción diastólica y sistólica temprana antes de producir síntomas asociados. Debido a lo anterior es de suma importancia entender esta patología desde el plano fisiopatológico, por otra parte, establecer un diagnóstico oportuno por métodos establecidos como el ecocardiograma y posibles tratamientos en la actualidad para la mejoría de la contractibilidad miocárdica. En el presente artículo se revisan los mecanismos fisiopatológicos en base a los procesos metabólicos en la diabetes mellitus que afectan el miocardio generando una disminicion en la eficiencia cardiaca por ende provocando una insuficiencia cardiaca a largo plazo, también se analizara los métodos diagnósticos más precisos y concluyentes para establecer la cardiomiopatía diabética. Por otro lado, se analizarán los efectos terapéuticos de los medicamentos inhibidores del cotransportador sodio-glucosa tipo 2 en el miocardio en base sus efectos beneficios ya demostrados y a la vez en teorías e hipótesis que se han planteado a partir de investigaciones experimentales y observacionales.

In this work, we review and expand recent theoretical proposals for the realization of electronic thermal diodes based on tunnel-junctions of normal metal and superconducting thin films. Starting from the basic rectifying properties of a single hybrid tunnel junction, we will show how the rectification efficiency can be largely increased by combining multiple junctions in an asymmetric chain of tunnel-coupled islands. We propose three different designs, analyzing their performance and their potential advantages. Besides being relevant from a fundamental physics point of view, this kind of devices might find important technological application as fundamental building blocks in solid-state thermal nanocircuits and in general-purpose cryogenic electronic applications requiring energy management.

Context. The Tibet AS and LHAASO collaborations recently reported the observation of a-ray diffuse emission with energy up to the PeV level from the Galactic plane. Aims. We discuss the relevance of non-uniform cosmic-ray transport scenarios and the implications of these results for cosmic-ray physics. Methods. We used the DRAGON and HERMES codes to build high-resolution maps and spectral distributions of that emission for several representative models under the condition that they reproduce a wide set of local cosmic-ray data up to 100 PeV. Results. We show that the energy spectra measured by Tibet AS, LHAASO, ARGO-YBJ, and Fermi-LAT in several regions of interest in the sky can all be reasonably described in terms of the emission arising by the Galactic cosmic-ray "sea". We also show that all our models are compatible with IceTop-ray upper limits. Conclusions. We compare the predictions of conventional and space-dependent transport models with those data sets. Although the Fermi-LAT, ARGO-YBJ, and LHAASO preliminary data slightly favor this scenario, due to the still large experimental errors, the poorly known source spectral shape at the highest energies, the potential role of spatial fluctuations in the leptonic component, and a possible larger-than-expected contamination due to unresolved sources, a solid confirmation requires further investigations. We discuss which measurements will be most relevant in order to resolve the remaining degeneracy. [ABSTRACT FROM AUTHOR]

A nation often takes on the characteristics of its leaders. Consider the influence of Frederick the Great upon the German national ethos or Peter the Great upon Russia. Unlike other [...]

We present a comprehensive study about the phenomenological implications of the theory describing Galactic cosmic ray scattering on to magnetosonic and Alfvénic fluctuations in the GeV−PeV domain. We compute a set of diffusion coefficients from first principles, for different values of the Alfvénic Mach number and other relevant parameters associated with both the Galactic halo and the extended disc, taking into account the different damping mechanisms of turbulent fluctuations acting in these environments. We confirm that the scattering rate associated with Alfvénic turbulence is highly suppressed if the anisotropy of the cascade is taken into account. On the other hand, we highlight that magnetosonic modes play a dominant role in Galactic confinement of cosmic rays up to PeV energies. We implement the diffusion coefficients in the numerical framework of the dragon code, and simulate the equilibrium spectrum of different primary and secondary cosmic ray species. We show that, for reasonable choices of the parameters under consideration, all primary and secondary fluxes at high energy (above a rigidity of |$\simeq 200 \, \mathrm{GV}$|⁠) are correctly reproduced within our framework, in both normalization and slope. [ABSTRACT FROM AUTHOR]

A fundamental aspect of electronics is the ability to distribute a charge current among different terminals. On the other hand, despite the great interest in dissipation, storage, and conversion of heat in solid state structures, the control of thermal currents at the nanoscale is still in its infancy. Here, we show the experimental realization of a phase-tunable thermal router able to control the spatial distribution of an incoming heat current, thus providing the possibility of tuning the electronic temperatures of two output terminals. This ability is obtained thanks to a direct current superconducting quantum interference device (dc SQUID), which can tune the coherent component of the electronic heat currents flowing through its Josephson junctions. By varying the external magnetic flux and the bath temperature, the SQUID allows us to regulate the size and the direction of the thermal gradient between two drain electrodes. Our results offer new opportunities for all microcircuits requiring an accurate energy management, including electronic coolers, quantum information architectures, and thermal logic components. [ABSTRACT FROM AUTHOR]

In this work, we review and expand recent theoretical proposals for the realization of electronic thermal diodes based on tunnel-junctions of normal metal and superconducting thin films. Starting from the basic rectifying properties of a single hybrid tunnel junction, we will show how the rectification efficiency can be largely increased by combining multiple junctions in an asymmetric chain of tunnel-coupled islands. We propose three different designs, analyzing their performance and their potential advantages. Besides being relevant from a fundamental physics point of view, this kind of devices might find important technological application as fundamental building blocks in solid-state thermal nanocircuits and in general-purpose cryogenic electronic applications requiring energy management. [ABSTRACT FROM AUTHOR]

Thermal diodes-devices that allow heat to flow preferentially in one direction-are one of the key tools for the implementation of solid-state thermal circuits. These would find application in many fields of nanoscience, including cooling, energy harvesting, thermal isolation, radiation detection and quantum information, or in emerging fields such as phononics and coherent caloritronics. However, both in terms of phononic and electronic heat conduction (the latter being the focus of this work), their experimental realization remains very challenging. A highly efficient thermal diode should provide a difference of at least one order of magnitude between the heat current transmitted in the forward temperature (T) bias configuration (Jfw) and that generated with T-bias reversal (Jrev), leading to ℛ = Jfw/Jrev ≫ 1 or ≪ 1. So far, ℛ ≈ 1.07-1.4 has been reported in phononic devices, and ℛ ≈ 1.1 has been obtained with a quantum-dot electronic thermal rectifier at cryogenic temperatures. Here, we show that unprecedentedly high ratios of ℛ ≈ 140 can be achieved in a hybrid device combining normal metals tunnel-coupled to superconductors. Our approach provides a high-performance realization of a thermal diode for electronic heat current that could be successfully implemented in true low-temperature solid-state thermal circuits. [ABSTRACT FROM AUTHOR]

We report the realization and investigation of a ballistic Andreev interferometer based on an InAs two dimensional electron gas coupled to a superconducting Nb loop. We observe strong magnetic modulations in the voltage drop across the device due to quasiparticle interference within the weak-link. The interferometer exhibits flux noise down to ~80 μɸ0/√Hz and a robust behavior in temperature with voltage oscillations surviving up to ~7K. Besides this remarkable performance, the device represents a crucial first step for the realization of a fully-tunable ballistic superconducting magnetometer and embodies a potential advanced platform for the investigation of Majorana bound states, non-local entanglement of Cooper pairs, as well as the manipulation and control of spin triplet correlations. [ABSTRACT FROM AUTHOR]

We propose a low-temperature thermal rectifier consisting of a chain of three tunnel-coupled normal metal electrodes. We show that a large heat rectification is achievable if the thermal symmetry of the structure is broken and the central island can release energy to the phonon bath. The performance of the device is theoretically analyzed and, under the appropriate conditions, temperature differences up to ~200 mK between the forward and reverse thermal bias configurations are obtained below 1K, corresponding to a rectification ratio R ~ 2000. The simplicity intrinsic to its design joined with the insensitivity to magnetic fields make our device potentially attractive as a fundamental building block in solid-state thermal nanocircuits and in general-purpose cryogenic electronic applications requiring energy management [ABSTRACT FROM AUTHOR]

We report the realization of a ballistic Josephson interferometer. The interferometer is made from a quantum ring etched in a nanofabricated two-dimensional electron gas confined in an InAs-based heterostructure laterally contacted to superconducting niobium leads. The Josephson current flowing through the structure shows oscillations with h/e flux periodicity when threading the loop with a perpendicular magnetic field. This periodicity, in sharp contrast with the h/2e one observed in conventional dc superconducting quantum interference devices, confirms the ballistic nature of the device in agreement with theoretical predictions. This system paves the way for the implementation of interferometric Josephson π-junctions, and for the investigation of Majorana fermions. [ABSTRACT FROM AUTHOR]

The magnetoelectrostatic tailoring of the supercurrent in quantum point contact ballistic Josephson junctions is demonstrated. An etched InAs-based heterostructure is laterally contacted to superconducting niobium leads, and the existence of two etched side gates permits, in combination with the application of a perpendicular magnetic field, continuous modification of the magnetic interference pattern by depleting the weak link. For wider junctions the supercurrent presents a Fraunhofer-like interference pattern with periodicity h/2e, whereas by shrinking electrostatically the weak link, the periodicity evolves continuously to a monotonic decay. These devices represent tunable structures that might lead to the study of the elusive Majorana fermions. [ABSTRACT FROM AUTHOR]

The nature of the cells which form the inflammatory reaction against tumor cells in pre-cancerous and cancerous lesions of the lip has been investigated by electron microscopy. The aim of the research was to ascertain the possible role of these cells for the tumor cell degeneration that has been observed in this tumor system. Ultrastructural studies have revealed that the inflammatory infiltrates seen in the vicinity of tumor cells, consist of lymphocytes, plasma cells and cells of the macrophagic series. The relative predominance of the individual cell type varies from one case to another, probably depending on the clinical situation of the patient. However, lymphocytes have been found to be present in all the cases studied and to be predominant in 4 cases out of 5; plasma cells were predominant in 1 case out of 5; and macrophages were never observed to be very numerous. Most of lymphocytes have the morphological characteristics of T-cells and were seen in close contact with tumor cells, some of which appeared to be undergoing degenerative changes. These observations are consistent with current hypotheses regarding the role of lymphocytes in the development of cancers. The authors conclude that the chronic inflammatory process, that is seen during the development of squamous cell carcinoma in the lip, is to be interpreted as the cellular expression of an immune reaction against tumor cells. However further studies of the function of these cells are required to identify their precise individual role. [ABSTRACT FROM AUTHOR]

A case of cutis laxa acquisita was studied with the aim of defining the molecular defects involved and comparing them with those of an inherited form of cutis laxa. In the acquisita form of cutis laxa ultrastructural and biochemical observations confirmed a dramatic reduction of dermal elastin, whereas collagen content was normal. Elastin mRNA expression as well as tropoelastin production by dermal fibroblasts, in vitro, were normal compared with control cells, as revealed by in situ hybridization and enzyme-linked immunosorbent assay, respectively. Lysyl oxidase activity, measured on cultured fibroblasts, was reduced to 60% compared with age-matched control subjects. Unlike control skin fibroblasts or fibroblasts from inherited cutis laxa, the affected skin cells from cutis laxa acquisita predominantly expressed an elastolytic activity identified as cathepsin G. Patient serum also has reduced elastase inhibitory capacity and reduced levels of α1-antiproteinase inhibitor (α1-antitrypsin). Although cutis laxa acquisita is a heterogeneous group of disorders, findings in this patient were consistent with excessive loss of cutaneous elastin due to the combined effects of several factors, such as low lysyl oxidase activity together with high levels of cathepsin G and reduction of circulating proteinase inhibitor(s). [ABSTRACT FROM AUTHOR]

We investigate the thermal transport properties of a temperature-biased Josephson tunnel junction composed of two different superconductors. We show that this simple system can provide a large negative differential thermal conductance (NDTC) with a peak-to-valley ratio of ~3 in the transmitted electronic heat current. The NDTC is then exploited to outline the caloritronic analog of the tunnel diode, which can exhibit a modulation of the output temperature as large as 80 mK at a bath temperature of 50 mK. Moreover, this device may work in a regime of thermal hysteresis that can be used to store information as a thermal memory. On the other hand, the NDTC effect offers the opportunity to conceive two different designs of a thermal transistor, which might operate as a thermal switch or as an amplifier/modulator. The latter shows a heat amplification factor >1 in a 500-mK-wide working region of the gate temperature. After the successful realization of heat interferometers and thermal diodes, this kind of structures would complete the conversion of the most important electronic devices in their thermal counterparts, breaking ground for coherent caloritronics nanocircuits where heat currents can be manipulated at will. [ABSTRACT FROM AUTHOR]