A S=1/2 vanadium-based geometrically frustrated spinel system Li2ZnV3O8

We report the synthesis and characterization of Li2ZnV3O8, which is a new Zn-doped LiV2O4 system containing only tetravalent vanadium. A Curie-Weiss susceptibility with a Curie-Weiss temperature of CW ~214 K suggests the presence of strong antiferromagnetic correlations in this system. We have observed a splitting between the zero-field cooled ZFC and field cooled FC susceptibility curves below 6 K. A peak is present in the ZFC curve around 3.5 K suggestive of spin-freezing . Similarly, a broad hump is also seen in the inferred magnetic heat capacity around 9 K. The consequent entropy change is only about 8% of the value expected for an ordered S = 1=2 system. This reduction indicates continued presence of large disorder in the system in spite of the large CW, which might result from strong geometric frustration in the system. We did not find any temperature T dependence in our 7Li nuclear magnetic resonance NMR shift down to 6 K (an abrupt change in the shift takes place below 6 K) though considerable T-dependence has been found in literature for LiV2O4- undoped or with other Zn/Ti contents. Consistent with the above observation, the 7Li nuclear spin-lattice relaxation rate 1/T1 is relatively small and nearly T-independent except a small increase close to the freezing temperature, once again, small compared to undoped or 10% Zn or 20% Ti-doped LiV2O4.Comment: 7 pages, 8 figures, accepted in JPCM (Journal of Physics condensed matter

Use of del nido cardioplegia versus St. thomas solution 2 in adult mitral valve replacement surgery at a tertiary care hospital in Kolkata, India

Background: del Nido cardioplegia has been historically used in paediatric cardiac surgery. However it’s use in adults has also been documented. It has the advantage of 90 minutes of cardiac inactivity over St. Thomas solution no.-2, which requires repeated dosing at 20 minutes interval. Aim of this study to find out whether del Nido cardioplegia with longer duration of arrest is advantageous over St. Thomas solution no. 2 in adult mitral valve replacement.Methods: Total 60 patients of severe mixed mitral valve disease of comparable patient profiles, underwent mitral valve replacement with preservation of anterolateral and posteromedial chordae. Half the patients received del Nido cardioplegia and other half received St. Thomas solution no 2. (ST-2). The two groups were compared.Results: del Nido group had lesser CPB time (70.73±12.15min) as compared to ST-2 group (81.76±20.03min) with  p=0.01 ; lesser Cross clamp time (del Nido- 68.8±10.64min; ST-2- 75.83±14.00min) with p=0.02; lesser time taken to arrest heart  (del Nido- 21.58±13.37 sec; ST-2- 25.26±5.27 sec) with p=0.04 & lesser time taken for normal ECG activity to manifest after release of cross clamp (del Nido- 19.86±6.10 min; ST-2- 31.03±5.28min) with p=0.02. All other parameters did not reach statistical significance.Conclusions: del Nido cardioplegia group of patients required significantly less CPB time; Cross-clamp time; Mean time taken to arrest the heart; as well as that taken to manifest normal ECG morphology when compared to ST-2 group

Algorithm based new Tone Reservation method for mitigating PAPR in OFDM systems

There are abundant methods to mitigate PAPR in OFDM signals among which algorithm based tone reservation is of great popularity owing to its low complexity as well as decent BER. Here we have put forward a new distinct algorithm based Tone Reservation technique which is not only less complex and calculates its own threshold as well as PRT signal (unlike other algorithms requiring predetermined threshold and PRT) but also aptly modifies the data by bit by bit comparison with a modified copy of itself (algorithm modified) thus scaling the peaks as and providing a decent BER and good PAPR reduction.

A 6 months retrospective observational study to assess the rationality and effectiveness of snake bite management in a tertiary care teaching hospital of rural Bengal, India

Background: Snake envenomation is a common life-threatening problem encountered all-over West Bengal particularly in the rural areas. There are a large number of patients attending the Emergency unit and being admitted to the Medicine ward, some in the intensive care unit (ICU) and intensive therapy unit (ITU) of the tertiary health care facilities. The objective of this study was to assess rationality and effectiveness of management of venomous snake bite following standard protocol – Standard treatment guidelines of Government of West Bengal and National snakebite management protocol of Government of India.Methods: This was a retrospective observational study of six months (May - October 2017) duration. Data were collected from the treatment records of patients admitted with history of snake bite in the Medicine ward, ICU and ITU of tertiary care teaching hospital of rural Bengal.Results: Of the 63 venomous bite patients, most (82.5 %) were diagnosed to have features of neurotoxic envenomation. All of them (100%) received anti-snake venom (ASV). There was no incidence of anaphylactic reaction as well as any serious adverse drug reaction following ASV administration. Two patients developed acute renal failure, needed haemodialysis. Overall percentage of mortality was 3.2%.Conclusions: The survival rate in venomous snake bite is found to be high in this institution. The practice of snake bite management is found to be adherent with standard protocol. A multicentric study of longer duration is suggested to draw a firm conclusion

Large spontaneous exchange bias in a weak ferromagnet Pb6Ni9(TeO6)5

We report the magnetic and dielectric behavior of Pb6Ni9(TeO6)5, a new compound comprising the honeycomb-like layers of S=1 spins, through detailed structural, magnetic and dielectric investigation. An antiferromagnetic-type transition at 25 K (TN) with weak-ferromagnetic behavior is revealed. Interestingly, a large value of coercive field of 1.32 T at 2 K is observed. The isothermal magnetization after zero-field-cooled condition, it exhibits the presence of large spontaneous exchange bias (SEB) with a magnitude of 0.19 T at 2 K; which is rare in single bulk materials, especially without external doping. The value of |HEB| further enhances to 0.24 T under 16 T field-cooled condition, confirming the presence of large exchange bias in the material. In addition, the dielectric constant shows an anomaly at the onset of TN, indicating the presence of magnetodielectric coupling.Comment: 16 pages, 6 figures, 2 supplimentory figures, under revision of Scientific Report

Large spontaneous exchange bias in a weak ferromagnet Pb6Ni9(TeO6)(5)

Correction to: Scientifc Reports https://doi.org/10.1038/s41598-017-09056-w, published online 15 August 2017. In the original version of this Article, Binoy Krishna Hazra and S. Srinath were incorrectly affiliated with‘Department of Physics, Indian Institute of Technology Tirupati, TIRUPATI, 517506, India’. The correct affliation is listed below: School of Physics, University of Hyderabad, Hyderabad, 500046, India This error has now been corrected in the PDF and HTML versions of the Article, and in the accompanying Supplementary Information file.International audienceWe report the magnetic and dielectric behavior of Pb6Ni9(TeO6)(5), a new compound comprising the honeycomb-like layers of S = 1 spins, through detailed structural, magnetic and dielectric investigation. An antiferromagnetic-type transition at 25 K (T-N) with weak-ferromagnetic behavior is revealed. Interestingly, a large value of coercive field of 1.32 T at 2 K is observed. The isothermal magnetization after zero-field-cooled condition, it exhibits the presence of large spontaneous exchange bias (SEB) with a magnitude of 0.19 T at 2 K; which is rare in single bulk materials, especially without external doping. The value of |H-EB| further enhances to 0.24 T under 16 T field-cooled condition, confirming the presence of large exchange bias in the material