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eVIN is a technology system that digitizes vaccine stocks through a smartphone application and builds the capacity of program managers and cold chain handlers to integrate technology in their regular work. To effectively manage the vaccine logistics, in 2015, this technology was rolled-out in 12 states of India. This study assessed the programmatic usefulness of eVIN implementation in the areas of vaccine utilization, vaccine stock and distribution management and documentation across selected cold chain points. A pre-post study design was used, where cold chain points (CCPs) were selected using two-stage sampling technique in eVIN states. Pre-post comparative analysis was carried out on the identified indicators using both primary and secondary data sources. The vaccine utilization data reflects that the utilization had reduced from 305.3 million doses in pre-eVIN period to 215.0 million doses in post-eVIN period across 12 eVIN states, resulting into savings of approximately 90 million doses of vaccines. Number of facilities having stock-out of any vaccine showed a significant reduction by 30.4% in post-eVIN period (p<0.001). There was a 4.0% drop in facilities reporting minimum stock of any vaccine after implementation of eVIN. Facilities with maximum stock of any vaccine had increased from 37.4% in pre-eVIN to 39.2% in post-eVIN. During the pre-eVIN period, only 38.6% facilities updated vaccine stock on a daily basis, while in post-eVIN period, 53.5% facilities updated vaccine stock on daily basis. The completeness of records in the vaccine stock registers, indent form and temperature logbook have been substantially improved in the post-eVIN period (p<0.001). eVIN had helped in streamlining the vaccine flow network and ensured equity through better vaccine management practices. It is a powerful contribution to strengthen the vaccine supply chain and management. Upscaling eVIN in the remaining states of India will be crucial in improving the efficacy of vaccines and cold chain management., Competing Interests: The authors have declared that no competing interests exist

A new technique for improving field dependence in Bi-2223 superconducting tapes at 77K is described.

The testing of the largest Bi-2223 high temperature superconducting coil is described and results are presented.

A 15 kV, 20 kA HTS fault current limiter was design and developed as part of a Department of Energy Superconductivity Partnership INitiative.

The powder-in-tube technique was used to fabricate multifilamentary silver-clad Bi-2223 tapes with the precursor powder containing Pb-added 2212, Ca2PbO4, alkaline-earth cuprate and CuO phases and having the overall stoichiometry of Bi-2223. Varying the mechanical and thermal processes during tape processing improved the transport current properties in these multifilament silver-clad Bi-2223 superconducting tapes. Experimental methods and findings are presented.

Alternating current (ac) losses for a stack of Bi2223/Ag were found to be a function of the angular difference between the tape face and the applied ac magnetic field. The results were compared against the values derived by using the Bean critical-state model. The subsequent analysis revealed that, despite the seeming agreement of the Bean model with the general qualitative behavior of the calculated loss, the model failed substantially in its predictions.

Metal Organic Chemical Vapor Deposition (MOCVD) was used to deposit YBa2Cu3Ox (YBCO) films on buffered metal substrates. A thermonuclear process was used to fabricate cube-textured nickel substrates. Thermal evaporation was then used to deposit epitaxial CeO2 films on these substrates. MOCVD was also used to deposit highly biaxially-textured YBCO films on both types of metal substrates. The results showed that a critical current density greater than 10 to the fifth power A/cm2 at 77 K has been achieved in YBCO films on metal substrates.

Research was conducted to examine a 5-m-long alternating current transmission line model with 1kA current capability at 77 K. Emphasis was on the alternating current losses and current characteristics in individual tapes and in the core of the cable. The capability of the transmission line model was investigated using currents of up to 1200 A. Results showed that the current capability of the current core correlates well with data derived for single tapes.

Lockheed Martin, American Superconductor Corp, Southern California Edison (SCE) and the Los Alamos National Laboratory have been jointly developing and testing a 2.4 kV high temperature superconducting fault current limiter. The device is based on a Bi-2223 Ag conductor and features a fault current of 2.2 kArms and continuous current of 150 Arms. The fault current limiter was subjected to six-weeks of extensive testing at SCE's Norwalk, CA, Center Substation.

The powder-in-tube method was utilized in fabricating high-quality long-length mono- and multi-filament Bi2223 conductors, with particular emphasis on careful control of processing parameters. A 1,260-meter-long multifilament conductor with 37 monocore filaments exhibited a critical current density of up to 1.2x10(super 4) Acm-2 at 77 K. The conductor was then used for characterizing a prototype transformer and a high temperature superconducting magnet.

The powder-in-tube (PIT) and surface-coated conductor methods were utilized in fabricating Tl-1223 conductors. Short monofilament tapes and meter-long 37-filament tapes exhibited current densities of 20,000 A/cm2 and 12,000 A/cm2 at 77 K, respectively. A new method was also proposed for the development of PIT Tl-1223 conductors with grain alignment. The approach successfully fabricated conductors with critical currents of 18 A and a 19,000A/cm2 Jc.

A study was conducted on the influence of direct current transport currents on alternating current losses by the magnetically induced currents in silver-sheathed Bi(2223) tapes. Results were in agreement with a theory based on the the bean critical state model. Quantitative inconsistencies between the measurements and the theory were discussed and their sources analyzed.

Thermometric measurements were conducted on the self-field alternating current losses in silver-sheathed PbBi2223 multifilamentary tapes. The thermometric approach calculated the temperature profile of a vacuum insulated sample with both ends at a fixed temperature. A loss-induced temperature increase as low as 2mK was obtained by reducing the bath superheat, thermal electromagnetic field and by heating at the current contacts.

Alternating current (AC) transport current-induced energy losses were measured in silver sheathed mono core Tl-1223 and multifilamentary Bi-2223 tapes as a function of the applied external magnetic field's orientation and magnitude. The external magnetic field, which was rotated in the 0 to +/-90-degrees range, was kept perpendicular to the transport current flow. Transport current loss measurements in direct current (DC) applied fields were in agreement with Norris equation when the DC critical current is used for the expression of the loss.

The vortex solid-liquid phase transformation phenomenon was used as the magnetic field scaling factor to investigate the field-dependence of the flux pinning force in tapes silver-sheathed Bi2Sr2Ca2Cu3O10 tapes at temperatures above 27 K. To this end, transport measurements were performed on tapes immersed in liquid neon and in liquid oxygen. Consequently, it was shown that the vortex solid-liquid transition is the key parameter that limits the critical current density of such tapes in magnetic fields at temperatures above 27 K.

The impact of processing parameters on the microstructural and superconducting properties silver-sheathed Tl0.78Pb0.5Ba0.4Sr1.6Ca2Cu3Oy tapes was investigated. Specifically, uniaxially pressed tapes fabricated via the powder-in-tube method were subjected to different intermediate pressing stresses in between thermal treatment. This, together with changes in oxygen partial pressure and anneal periods, were found to have significant effects on the tapes' ampacity.

The melt

The c-axis conduction characteristics of silver-clad Bi-2223 and Bi-2212 tapes were investigated. Specifically, transport, resistivity and critical current measurements were carried out under varying temperatures and magnetic fields. The measurements, which looked at the superconducting current path parallel and perpendicular to the tape plane, revealed that the critical currents flowing along and normal to the tape plane have similar field orientation and magnetic field dependences.

The performance of silver-sheathed BSCCO (Bi-2223) single-pancake coils in static and ramped magnetic fields were investigated. Specifically, the critical currents of four Bi-2223 samples were measured at fields from zero to five tesla and at temperatures between 4.2 K and 105 K. In addition, one of the samples was subjected to field ramp rates of up to 1.5 T/s. The results, which revealed negligible eddy current heating in ramped fields, showed that Bi-2223 performance degrades rapidly at temperatures higher than 40 K.

We report results on the critical current density [J.sub.c](T,H) at various fields and temperatures of Bi-2223/Ag tapes and small coils. In field measurements on small coils were performed under ascending and descending fields to investigate hysteretic behavior. Strain dependence of [J.sub.c] was obtained by bending heat treated tapes around mandrels of varying diameters. Microstructural results of these tapes by optical microscopy, SEM, EDS, WDS are also presented.

Changes in the superconducting properties of multifilamentary NbTi superconductors with artificial pinning centers due to the NbTi alloy and pin spacing, pin material and geometry were investigated. Pinning center spacing were matched to the flux line lattice spacing at field of operation in order to attain peak current densities. Results indicated that the qualities of the pinning force of the alloy were significantly affected by the factors examined.

The characterization of silver-sheathed Bi-2223 superconducting tapes has been carried out. The high-temperature superconducting tapes, which were powder-in-tube processed, were subjected to a microstructural evaluation and critical current density measurements at temperatures ranging from 4.2 K to 77 K and under different applied fields. The current-voltage characteristics of pancake coils built from such conductors were also determined.

A study on the strain tolerance of multifilamentary high-temperature superconducting wires manufactured via the powder-in-tube process was conducted. The experiment looked into the role of the fabrication procedure and heat treatment on the critical current densities of 80-m bismuth-lead-strontium-copper-oxide conductors. It was found that BPSCCO-2223 samples doped with antimony exhibits a critical current density close to 1000 A/cm2 when operated just beneath its transition temperature.

The deposition of YBaCu3Ox films on buffered metal substrates using metal organic chemical-vapour deposition is described.