A precision measurement by the Alpha Magnetic Spectrometer on the International Space Station of the positron fraction in primary cosmic rays in the energy range from 0.5 to 350 GeV based on $6.8\times {10}^6$ positron and electron events is presented. The very accurate data show that the positron fraction is steadily increasing from 10 to $\sim 250\mathrm{GeV}$, but, from 20 to 250 GeV, the slope decreases by an order of magnitude. The positron fraction spectrum shows no fine structure, and the positron to electron ratio shows no observable anisotropy. Together, these features show the existence of new physical phenomena.

Taking into account the increasing penetration of renewable energy sources in the electric grid it has become important to manage these resources to improve the availability, reliability and quality of the electric power. In order to connect to the electric grid a solar photovoltaic (PV) plant with the characteristic of energy management plant it is required a set of conditions established by the transmission system operator (TSO). Among those, there are important points as the reliability in the power prediction, obligation to provide energy reserve and support to voltage disturbances. In order to provide a reserve of energy, some possibilities are proposed in this paper, all of them based on the energy storage system concept. A hybrid batteries and flywheels solution will be analysed for a specific application of 1MW, 1MWh solar photovoltaic plant. Only technical evaluation has been developed.

Recent advances in superconducting materials are giving renewed impetus to different power applications, some of which already existed based on previous superconductors with more modest properties while some others have been the symbiosis of new requirements in science and technology and better properties of the new superconductors. This paper constitutes a review of classical and new superconducting materials for power applications (the technological superconductors as they are frequently called) in terms of their structure and their engineering properties (electrical, mechanical and thermal) but also in terms of their manufacturability and scalability for possible scenarios where massive quantities may be required. The second and longer part of the paper is a state of the art of power applications of superconductivity related to energy (generation, transport and transmission), transport (airborne, waterborne and terrestrial) and industrial processes. Practically, all these applications are based on superconducting magnets, which are addressed in the article, including new technologies regarding their design, fabrication and operation. Particularly, these magnets can be the coils of superconducting electrical machines, also described in the paper, where different applications are presented following a scheme of problems to be solved versus the solution provided by superconductivity, including benefits regarding sustainability improvement associated with their better efficiency and power consumption reduction.

The numerical evaluation of magnetic forces exerted by permanent magnets is usually performed by two methods, the integration of the Maxwell stress tensor or by means of virtual displacements and energy balance. In this paper, we will review previous works on this subject, where controversy exists due to the sign of the magnetic energy stored in the magnet itself. We will check the theoretical work in the matter with numerical results from a number of FEM codes, as Ansys, Opera and Quickfield. Several examples of application will be provided. One of those will be the particular case of a phase shifter under development for the XFEL (European X-Ray Free Electron Laser) project. Its purpose is to adjust the phase between two consecutive undulator segments. The magnetic field is obtained in this device through a Halbach hybrid configuration with Nd-Fe-B permanent magnets and Fe-Co poles.