Electrical and Magnetic behaviour of PrFeAsO0.8F0.2 superconductor

The superconducting and ground state samples of PrFeAsO0.8F0.2 and PrFeAsO have been synthesised via easy and versatile single step solid state reaction route. X-ray & Reitveld refine parameters of the synthesised samples are in good agreement to the earlier reported value of the structure. The ground state of the pristine compound (PrFeAsO) exhibited a metallic like step in resistivity below 150K followed by another step at 12K. The former is associated with the spin density wave (SDW) like ordering of Fe spins and later to the anomalous magnetic ordering for Pr moments. Both the resistivity anomalies are absent in case of superconducting PrFeAsO0.8F0.2 sample. Detailed high field (up to 12Tesla) electrical and magnetization measurements are carried out for superconducting PrFeAsO0.8F0.2 sample. The PrFeAsO0.8F0.2 exhibited superconducting onset (Tconset) at around 47K with Tc({\rho} =0) at 38K. Though the Tconset remains nearly invariant, the Tc({\rho} =0) is decreased with applied field, and the same is around 23K under applied field of 12Tesla. The upper critical field (Hc2) is estimated from the Ginzburg Landau equation (GL) fitting, which is found to be ~ 182Tesla. Critical current density (Jc) being calculated from high field isothermal magnetization (MH) loops with the help of Beans critical state model, is found to be of the order of 103 A/cm2. Summarily, the superconductivity characterization of single step synthesised PrFeAsO0.8F0.2 superconductor is presented.Comment: 15 Pages Text + Fig

A nod in the wrong direction : Does nonverbal feedback affect eyewitness confidence in interviews?

Eyewitnesses can be influenced by an interviewer's behaviour and report information with inflated confidence as a result. Previous research has shown that positive feedback administered verbally can affect the confidence attributed to testimony, but the effect of non-verbal influence in interviews has been given little attention. This study investigated whether positive or negative non-verbal feedback could affect the confidence witnesses attribute to their responses. Participants witnessed staged CCTV footage of a crime scene and answered 20 questions in a structured interview, during which they were given either positive feedback (a head nod), negative feedback (a head shake) or no feedback. Those presented with positive non-verbal feedback reported inflated confidence compared with those presented with negative non-verbal feedback regardless of accuracy, and this effect was most apparent when participants reported awareness of the feedback. These results provide further insight into the effects of interviewer behaviour in investigative interviewsPeer reviewedFinal Accepted Versio

Structural, Magnetic and Magneto-caloric studies of Ni50Mn30Sn20Shape Memory Alloy

We have synthesized a nominal composition of Ni50Mn30Sn20 alloy using arc melting technique. Rietveld refinement confirms the austenite L21 structure in Fm-3m space group. Electrical resistivity has been found to clearly exhibiting two different phenomena viz. a magnetic transition from paramagnetic to ferromagnetic and a structural transition from austenite to martensitic phase. Thermo-magnetization measurements M(T) confirms ferromagnetic transition temperature TC at 222 K and martensitic transition starting at 127 K(MS). Magnetization measurement M(H) at 10 K confirms the ferromagnetic state. Frequency dependence of ac susceptibility \c{hi}' at low temperature suggests spin glass behavior in the system. The isothermal magnetic entropy change values have been found to be 1.14 J/Kg.K, 2.69 J/Kg.K and 3.9 J/Kg.K, with refrigeration capacities of 19.6 J/kg, 37.8 J/kg and 54.6 J/kg for the field change of 1, 2 and 3 Tesla respectively at 227 K.Comment: 16 pages text + Figs. Ni50Mn30Sn20 alloy: reasonable refrigeration capacity tunable to Room

Regional characterization of pigeonpea sterility mosaic disease and exploring broad-based resistance

Pigeonpea sterility mosaic disease (SMD) caused by Pigeonpea sterility mosaic virus (PPSMV) is a serious threat to pigeonpea production in the Indian-subcontinent. Recent reports on the possible existence of two different viruses associated with the SMD further complicate the etiology of this difficult to manage viral disease. In this regard, a comprehensive and systematic survey was taken up across several pigeonpea growing areas in southern India to know the disease prevalence and variability in virus isolates. Further, selected pigeonpea elite genotypes were screened in different locations for their broad-based resistance. Results indicate huge variation in SMD incidence among the surveyed states. The highest disease incidence (9.38 percent) was observed in Karnataka, followed by Tamil Nadu state with 8.44 per cent incidence. Andhra Pradesh and Telangana states recorded disease incidences of 4.51 and 2.08 per cent respectively. Samples collected from Patancheru location and tested using viral-specific RNA-3 segment primers were all positive for both the viruses. However, one of the samples collected from Bengaluru location and four samples from Coimbatore location had a positive reaction for PPSMV-2 only. In order to identify broad-based resistance to SMD, 20 pigeonpea genotypes were screened in three different locations (Patancheru, Bengaluru and Coimbatore) in southern-India during rainy seasons of 2017 and 2018. Among them, ICPL- 16078, ICPL-16086 and ICPL-16087 showed resistance reaction ((≤10 % incidence) in all the three locations, whereas, ICPL-16072, ICPL-16077 and ICPL-16083 showed resistance to Patancheru and Coimbatore isolates but highly susceptible (≥40 % incidence) to Bengaluru isolate