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Over the past thirty years, Ukraine has seen three public protests that have come to be known as ‘revolutions’. Yet despite these repeated demonstrations of ‘people power’, Ukraine’s civil society has been too often underestimated or dismissed as ‘weak’ in academic literature. This thesis confronts this paradox, tracing the development of civil society in Ukraine and uncovering the roots of its vitality in ‘informal social capital’, a byproduct of statelessness and internal colonialism. Analysing the dataset of the European Social Survey (ESS) conducted in Ukraine biannually between 2002–2012, which illustrated that Ukrainians consistently sustained the ‘networks, norms, and social trust that facilitate coordination and cooperation for mutual benefit’ at the heart of the classic definition of social capital (Putnam 1995, 67), I argue that Ukraine’s particular social capital resides not in strong democratic institutions, but in vibrant cultures of informal mutual self-help in local and professional communities. My discussion suggests that, in the case of Ukraine, neither democratic governance nor the rule of law represents the sine qua non for an impactful civil society. To understand these cultures of informal mutual self-help, I offer four close readings of sustainable grassroots public service initiatives in post-Maidan Ukraine – Hromadske, StopFake, Prometheus and ProZorro – informed by semi-structured interviews with the activists who launched them. These civic entrepreneurs cite an ideational dedication to the common good and a keen understanding of the reform inefficiencies of the state as principal drivers for their emergence as activists. Since 2014, their initiatives have served millions of Ukrainians and cultivated Ukrainian civil society in the face of urgent economic, political and military crises. I explore the central role of social networks in mobilising pro bono professionals to compensate for inadequacies of the state and overcome a dramatic lack of financial resources and in achieving organisational sustainability over the long term. Ultimately, I show that a motivation for volunteering and extensive social mutual self-help networks of cooperation and trust, coupled with the availability of the unpoliced and highly accessible digital media, have led to the development of a robust ‘digital civil society’ in Ukraine. Digital media affordances allow grassroots civic initiatives to gain scale and institutionalise themselves, retaining the horizontal ethos of co-production. The case of Ukraine thus contributes to a growing body of evidence of the strength of informal digital civic activism in post-Soviet and post-colonial societies, inviting us to revisit the presuppositions of the liberal paradigm in civil society studies, which have dominated the scholarly debate in Western Europe and Northern America since the early 2000s., Cambridge Trust scholarship, CEELBAS Affiliate Award

The fusion power density produced in a tokamak is proportional to its magnetic field strength to the fourth power. Second-generation high temperature superconductor (2G HTS) wires demonstrate remarkable engineering current density (averaged over the full wire), JE, at very high magnetic fields, driving progress in fusion and other applications. The key challenge for HTS wires has been to offer an acceptable combination of high and consistent superconducting performance in high magnetic fields, high volume supply, and low price. Here we report a very high and reproducible JE in practical HTS wires based on a simple YBa2Cu3O7 (YBCO) superconductor formulation with Y2O3 nanoparticles, which have been delivered in just nine months to a commercial fusion customer in the largest-volume order the HTS industry has seen to date. We demonstrate a novel YBCO superconductor formulation without the c-axis correlated nano-columnar defects that are widely believed to be prerequisite for high in-field performance. The simplicity of this new formulation allows robust and scalable manufacturing, providing, for the first time, large volumes of consistently high performance wire, and the economies of scale necessary to lower HTS wire prices to a level acceptable for fusion and ultimately for the widespread commercial adoption of HTS.

The European Union-funded Advanced Superconducting Motor Experimental Demonstrator (ASuMED) project started in May 2017 with the purpose of demonstrating the benefits of a new, fully superconducting motor for reaching the targets established by the Flightpath 2050 plan. The project aims at a motor power density of 20kW kg−1 using a high-temperature superconducting (HTS) stator. The rotor will use HTS stacks operating like permanent magnets. A highly efficient cryostat for the motor combined with an integrated cryogenic cooling system and associated power converter will be used. This article provides a general overview of the prototype that is currently being assembled and that will be tested soon.

Two major in-line quality control tools implemented at SuperOx in the production of textured templates for 2G HTS wire are the digital processing of optical images of the electropolished substrate surface and reflected high energy electron diffraction (RHEED) analysis of the texture of the IBAD-MgO layer. In routine production, we use these tools for continuous screening and early rejection of defective material and thus reduce cost of the finished wire. Overlapping images of the surface of the moving tape exiting the electropolishing system are taken and processed, to yield three quality parameters. The parameter values correlate with the surface roughness of the tape and with the presence of macroscopic debris and scratches. The distribution of the surface quality parameters along the length of the tape is recorded, and the images of the areas where the parameter values lie outside the acceptable quality range are stored for defect analysis. A RHEED system is incorporated in buffer layer deposition to analyze the IBAD-MgO layer texture. Parameters of diffraction spots correlate with the texture of the IBAD-MgO layer, which ultimately determines the quality of the HTS layer. The RHEED tool enables closed loop control of the process thus ensuring a very high yield of textured template production.

Vlad, Valentina Roxana et al., We present the preparation of a new architecture of coated conductor by Inkjet printing of low fluorine YBa2Cu3O7-x on top of SuperOx tape: CGO/LMO/IBAD-MgO/Y2O3/Al2O3/Hastelloy. A 5-layered multi-deposited, 475 nm thick YBCO film was structurally and magnetically characterized. A good texture was achieved using this combination of buffer layers, requiring only a 30 nm thin IBAD-MgO layer. The LF-YBCO CC reaches self-field critical current density values of JcGB~15.9 MA/cm2 (5 K), ~1.23 MA/cm2 (77 K) corresponding to an Ic(77K)=58.4 A/cm-width. Inkjet printing offers a flexible and cost effective method for YBCO deposition, allowing patterning of structures., This work was performed within the framework of the EUROTAPES project (FP7-NMP.2011.2.2-1 Grant no. 280432), funded by the EU. ICMAB research was financed by the Ministry of Economy and Competitiveness, and FEDER funds under projects MAT2011-28874-C02-01, MAT2014-51778-C2-1-R, ENE2014-56109-C3-3-R and Consolider Nanoselect CSD2007-00041, and by Generalitat de Catalunya (2009 SGR 770, 2015 SGR 753 and Xarmae). ICMAB acknowledges support from Severo Ochoa Program (MINECO, Grant SEV-2015-0496).

In this study, we prepared soldered joints of 2G HTS wires from three different manufacturers: SuNAM, SuperPower, and SuperOx. We used Pb 39 Sn 61 solder and varied the pressure applied on the joint during soldering in the 3.9-10.5 MPa range. We found that for all samples, joint resistivity decreased with increasing applied pressure. Practically important, very low joint resistivity values in the 10-15 nΩ·cm 2 range were reproducibly achieved in joints made with SuperPower and SuperOx wire. Resistivity of joints made with SuNAM wire was rather high, in the 40-90 nΩ·cm 2 range. No degradation in I c across joints occurred in joints made at up to 8 MPa applied pressure. In joints made with SuperOx wire at applied pressure above 8 MPa, there was I c degradation comparing to the initial I c of individual wires before joining. We speculate on the possible reasons for the different resistivity and I c degradation behavior of joints made with wires from different manufacturers.

// Irina N. Mikhaylova 1 , Irina Zh. Shubina 1 , George Z. Chkadua 1 , Natalia N. Petenko 1 , Lidia F. Morozova 1 , Olga S. Burova 1 , Robert Sh. Beabelashvili 2 , Kermen A. Parsunkova 3 , Natalia V. Balatskaya 4 , Dmitrii K. Chebanov 5 , Vadim I. Pospelov 6 , Valeria V. Nazarova 1 , Anastasia S. Vihrova 1 , Evgeny A. Cheremushkin 1 , Alvina A. Molodyk 1 , Mikhail V. Kiselevsky 1 and Lev V. Demidov 1 1 N.N. Blokhin Russian Cancer Research Center, Moscow, Russia 2 Laboratory of Genetic Engineering, Institute of Experimental Cardiology, Russian Cardiological Research and Production Complex, Moscow, Russia 3 Diagnostic Laboratory Clinical Center “Optimum”, Sochi, Russia 4 Department of Immunology and Virology, Moscow Helmholtz Research Institute of Eye Diseases, Moscow, Russia 5 RUDN University, Moscow, Russia 6 “Genetic Technologies and Analyses”, Moscow, Russia Correspondence to: Irina Zh. Shubina, email: irinashubina@mail.ru Keywords: cancer vaccine therapy; melanoma; predictive markers; B2-microglobulin Received: September 04, 2017 Accepted: March 22, 2018 Published: May 11, 2018 ABSTRACT Immunotherapy has shown promising results in a variety of cancers, including melanoma. However, the responses to therapy are usually heterogeneous, and understanding the factors affecting clinical outcome is still not achieved. Here, we show that immunological monitoring of the vaccine therapy for melanoma patients may help to predict the clinical course of the disease. We studied cytokine profile of cellular Th1 (IL-2, IL-12, IFN-γ) and humoral Th2 (IL-4, IL-10) immune response, vascular endothelial growth factor (VEGFA), transforming growth factor-β 2 (TGF-β 2), S100 protein (S100A1B and S100BB), adhesion molecule CD44 and serum cytokines β2-microglobulin to analyze different peripheral blood mononuclear cell subpopuations of patients treated with dendritic vaccines and/or cyclophosphamide in melanoma patients in the course of adjuvant treatment. The obtained data indicate predominance of cellular immunity in the first adjuvant group of patients with durable time to progression and shift to humoral with low cellular immunity in patients with short-term period to progression (increased levels of IL-4 and IL- 10). Beta-2 microglobulin was differentially expressed in adjuvant subgroups: its higher levels correlated with shorter progression-free survival and the total follow-up time. Immunoregulatory index was overall higher in patients with disease progression compared to the group of patients with no signs of disease progression.

Rare earth-based coated conductors have large ac magnetization losses, which hinder their use in a variety of applications. A common way to reduce these losses is by striating the superconductor into narrow filaments by means of laser ablation. Practical superconductors also need a sufficiently thick copper stabilization. The best way of creating copper-stabilized filamentized coated conductors is still to be found. In this paper, the ac magnetization losses of differently prepared 12 mm wide coated conductors manufactured by SuperOx were measured. The samples differ in terms of thicknesses of copper stabilization (5 and 10 μm), number of filaments (from 10 to 60), and order for copper deposition (filaments produced before or after electroplating the tape). The ac loss measurements were performed at 77 K in a wide range of frequencies of the external magnetic field, which allows determining the onset of coupling currents and the importance of the coupling losses. Complementary dc measurements of the transverse resistivity between filaments help to understand the path of the coupling currents. Thanks to the variety of tested samples and operating conditions, this paper provides a direct comparison of the two striation processes in commercially available high-temperature superconductor coated conductors.

An analysis of temperature changes in warm and cold air masses of extratropical cyclones in both hemispheres with their movement during geomagnetic disturbances at the minimum of solar activity was performed. The location and movement of air masses of cyclones was determined by thermobaric maps at the 500 hPa level. In the conditions of a classical cyclogenesis, a warm air mass cools from day to day, while the cold air mass warms up. During geomagnetic disturbances, favorable conditions for increasing intensity and cyclone lifetime are formed, i.e., in a warm air mass, the temperature increases at heights lower than 300 hPa, while a cold air mass warms up more slowly. The distributions of the temperature of air masses of extratropical cyclones were shown to change due to the changes in geomagnetic activity.

This work is devoted to high-rate pulsed laser deposition of BaSnO 3 -doped superconducting films on long buffered metal tape substrates with the use of pilot-scale equipment and common deposition conditions typical for commercial 2G high-temperature superconducting wire production at SuperOx Japan. BaSnO 3 inclusions were found to grow as nanocolumns elongated along the vertical direction and having biaxial texture. With BaSnO3 doping, the angular dependence of critical current measured at 77 K became much more isotropic. At 77 K, the lift-factor (I c /I c sf ) values in BaSnO 3 -doped samples increased almost twice in 0.5-3 T magnetic field in perpendicular orientation; at the same time, the absolute critical current increased only by 10%. At 4.2 K, in 0.5-3 T perpendicular field, the absolute critical current in doped samples increased 1.8 times.

Stacks of commercial high-temperature superconducting tape can be cut and soldered together to form slabs of a large range of shapes and sizes. They are most interesting for magnetic levitation applications due to the flexibility of geometry, allowing them to be created in large thin slabs suitable for planar rotary magnetic bearings and linear maglev bearings. In this paper, the axial levitation force was measured between a field cooled slab of 30 × 30 mm and a 25-mm-diameter rare-earth permanent magnet (PM), which produced a cylindrically symmetric field necessary in the context of rotary bearings. The force results were compared with that achieved between the same PM and a larger 43-mm-diameter bulk MgB2 disk, as well as to FEM modeling using the Perfectly Trapped Flux approximation.

Lightweight megawatt-range power cables in electric aircraft propulsion systems will allow reducing fuel consumption by more than a half. Taking into account the low voltage limitations for onboard use, superconductivity providing high current-carrying capacity becomes an enabling technology for this application. In the frame of a preliminary study of an onboard superconducting power distribution grid, we fabricated and tested a high-temperature superconducting (HTS) Roebel cable. The work was done by a consortium of institutions and supported by Airbus Group Innovations. SuperOx provided a 400 A-class 12-mm-wide 2G HTS wire. The team at the Karlsruhe Institute of Technology prepared 5.5-mm-wide Roebel strands with a transposition length of 226 mm and assembled the strands into a 6-m-long Roebel cable. The team at the Russian Scientific Research and Development Cable Institute performed characterization of the cable. Short samples of the cable were tested to determine their critical currents, mechanical properties, and stability during thermal cycling. For a 4-m-long section of the cable, we measured the critical current, as well as the transport ac losses at frequencies in the range from 50 to 400 Hz. This paper presents the cable design and test results. The feasibility of using 2G HTS Roebel cables in electric aircraft systems is discussed.

We investigate the field, angle and temperature dependence of the full-width critical current, I c, of pulsed laser deposition-grown GdBa2Cu3O7 coated conductors with and without additional 6 mol% BaSnO3 (BSO) nanoparticles fabricated by SuperOx. The transport characteristics measured from 7 to 77 K and in applied magnetic fields of up to 6 T are complemented by scanning transmission electron microscopy. This combined approach allows for further insight into the vortex pinning mechanism and helps with understanding the enhancement in I c. An exemplary scaling of the pinning force curves versus field at different temperatures confirms the additional contribution to pinning by the BSO nanoparticles. Through the temperature dependence of I c, the weak and strong pinning contributions are determined: strong pinning dominates over almost the entire temperature range especially near the matching field of 1 T, where the largest enhancement in I c is achieved.

In this work we present the study of the resistive transition in magnetic field of 2G HTS wire samples with BaSnO3 artificial pinning centres in GdBa2Cu3O7-x superconductor. The GdBCO layer was fabricated by pulsed laser deposition, using production equipment to obtain samples with varied concentration of APC: 0, 6, 12 and 18 mol.% of BaSnO3. Resistive transition curves were measured in the magnetic field range from 0 to 9 T, and magnetic field orientations from B||c (θ = 0°) to B||ab (θ = 90°) with an angle step of 15°. We observed an irreversibility temperature peak at the B||ab orientation. We determined the angular regions where correlated pinning centres dominated and found them to expand with the increase of BaSnO3 concentration. The activation energy (Ua) obtained from the lg(ρ/ρ0) against 1/T plots was almost constant in the whole angular range, with a small peak at B||ab. Activation energy as well as the irreversibility temperature decreased with increasing doping level, but the Ua(θ) curves looked similar for all samples with APC. The logarithmic resistivity plot of the undoped sample looked substantially different from those of the APC samples, with a kink and two different slopes corresponding to two regions with different Ua. We discuss that this difference is related to different pinning landscapes in samples with and without APC.

The potential of (RE)BCO superconducting bulks in rotating machine designs has been explored through numerous experimental prototypes, with the bulks being magnetized to act as held poles. However, stacks of superconducting tapes have emerged as a promising alternative for trapped held magnets partly because of their suitability for the pulsed-field method of magnetization, which is considered the most practical method of trapping flux. The benefits of using a stack of tapes as rotor held poles suitable for motors are reported. The ability to have a long rectangular stack allows for motor designs with more efficient held poles in terms of the flux produced per unit area of the pole and easy scalability. Such a rectangular stack was experimentally magnetized for the first time using a race-track-shaped pulsed-held coil giving a highly uniform and well-defined trapped held. The unique self-supporting 120 mm by 12 mm stack was produced by compressing a high-temperature-superconducting tape coated with a thin layer of solder. Shorter rectangular stacks were pulse magnetized over a temperature range of 10-77 K using a fully automated pulsed magnetization system.

$(\hbox{RE})\hbox{Ba}_{2}\hbox{Cu}_{3}\hbox{O}_{7-\delta}$ bulks are well known for their ability to trap high magnetic fields; however, it has been recently shown by the current authors that stacks of commercial YBCO-coated conductor tape can outperform YBCO bulks of similar size at temperatures below 60 K due to their superior thermal stability during multipulse magnetization. The latest progress in a comprehensive study being undertaken to optimize and tailor the stacks for applications will be discussed. In this paper, a method of binding layers of superconducting tape is reported, namely, soldering of Pb–Sn solder-coated high-temperature superconducting tape developed by SuperOx. The performance of tape before and after the soldering procedure is discussed, and a 100-layer stack, trapping a field of up to 1.6 T above the surface after pulse magnetization at 10 K, is reported.

International audience; This paper describes the standalone magnet cold testing of the high temperature superconducting (HTS) magnet Feather-M2.1-2. This magnet was constructed within the European funded FP7-EUCARD2 collaboration to test a Roebel type HTS cable, and is one of the first high temperature superconducting dipole magnets in the world. The magnet was operated in forced flow helium gas with temperatures ranging between 5 and 85 K. During the tests a magnetic dipole field of 3.1 T was reached inside the aperture at a current of 6.5 kA and a temperature of 5.7 K. These values are in agreement with the self-field critical current of the used SuperOx cable assembled with Sunam tapes (low-performance batch), thereby confirming that no degradation occurred during winding, impregnation, assembly and cool-down of the magnet. The magnet was quenched many tens of times by ramping over the critical current and no degradation nor training was evident. During the tests the voltage over the coil was monitored in the microvolt range. An inductive cancellation wire was used to remove the inductive component, thereby significantly reducing noise levels. Close to the quench current, drift was detected both in temperature and voltage over the coil. This drifting happens in a time scale of minutes and is a clear indication that the magnet has reached its limit. All quenches happened approximately at the same average electric field and thus none of the quenches occurred unexpectedly.

Many superconducting power applications contain REBCO coils. Superconducting motors are very interesting for mobile applications like aviation, thanks to their high power per unit weight. In order to reduce the inductance, multitape conductors are often used in windings but parallel tapes present coupling AC loss. In this article, we analyze the AC loss of single coils and a full stator of a motor made of windings of parallel tapes, taking several coupling situations into account. Our computer modeling method combines selfprogrammed and commercial finite-element methods to calculate the current density and AC loss. We found that isolating the tapes along the length provides almost the same AC loss reduction as that obtained by full transposition. This reveals that there are still many unexploited strategies to reduce the AC loss in multi-tape conductors.

If coated conductors are to be used in large-scale ac applications such as motors and generators, energy losses must be minimised. Hysteretic ac losses can be reduced by dividing the coated conductor into filaments. In this study, a new method for producing filamentary coated conductors is presented. An electrical spark discharge was used to selectively degrade regions of superconducting tape. The robust, noncontact and scalable method was used to striate tapes into four filaments. The filamentary samples had lower ac losses than nonstriated tapes with less than a 7% reduction in current carrying capacity.