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Background: Isometric handgrip (IHG) exercises can be a simple tool and an effective, time-consumable test that may be beneficial for blood pressure (BP) regulation. Hypertension prevention or BP control is necessary nowadays. Isometric exercise evokes the contractions of skeletal muscle without altering their length, but changes in the tension of the muscle occur. Through lifestyle modification, static exercises maintain the desired BP in individuals other than aerobic exercises. Aims and Objectives: The aim of the study was to evaluate the effective changes of isometric handgrip exercise on young, healthy subjects and determine changes in heart rate (HR) and BP before and after exercise. Materials and Methods: A randomized controlled study has been conducted in the department of physiology at JMC Rajasthan for 3 months. The study sample included 72 volunteer subjects (40 male and 32 females) aged 19-25 years, and handgrip spring dynamometer was used for isometric handgrip exercise (IHE) training exercise training. The IHE training group performed handgrip exercises for 3 months at 30% of their maximum isometric contraction, 3 times/week for five 3-min bouts with 5-min rest periods between each bout. Before and after the intervention, BP and HR were measured. P-value was advised significant at 0.05. Results: At the completion of 3 months of IHE exercise training, significant changes are seen in HR and BP in all healthy volunteers (P < 0.001 for all forms of BP) (HR, P = 0.014). In female volunteer and diastolic BP, it decreases significantly, but no significant changes are seen in systolic BP, mean arterial pressure, and HR. Conclusion: IHG exercise training reduces or regulates baseline BP and HR and explores the potential of this intervention for managing or preventing hypertension. [ABSTRACT FROM AUTHOR]

The layered multiferroic perovskite oxides are excellent functional materials for ferroelectric memory applications and also show application potential for cathode materials in lithium-oxygen battery due to high surface area, good stability, easy processing and low price. Synthesis of uniformly distributed layered perovskite oxides with low band gap, ionic-conducting and ferroelctric nature is still challenging. In this work, we have synthesized a new single-phase aurivillius phase Bi6FeNiTi3O18 ceramics by high-energy ball mill mechano-chemical reaction. The Rietveld refinement of XRD data reveals that the compound Bi6FeNiTi3O18 shows orthorhombic structure with space group P2/m and SEM images confirm the uniform layered morphology. Bi6FeNi Ti3O18 ceramic have shown very high Tc of 450 °C and typical relaxor behaviour. Impedance analysis reveals the effect of grains, grain boundaries and electrode on conductivity. Ferroelectric nature is confirmed by obtained P-E loop at room temperature. We also report much lower band gap (Eg = 1.87 eV) as compared to Bi6Fe2Ti3O18 (Eg = 3.2 eV) ceramics which is due to Ni 3d state formation below Fe 3d state. The present work provide new path to engineer the functional properties of perovskite oxides for memory and energy storage applications. [ABSTRACT FROM AUTHOR]

An ongoing and elusive task is to create single phase anode materials for solid oxide fuel cells (SOFC). Compared to the typical Ni-YSZ cermet anode, perovskite oxide based anode material has a number of benefits. Here, we present the structural and electrical characteristics of Y3+ doped SrTiO3 ceramics that are used as the anode in solid oxide fuel cells. The samples with nominal composition x = 0 and 0.05 were synthesized by high energy ball milling. The powder X-ray diffraction pattern reveals that the synthesized samples crystallize into cubic crystal structure with space group Pm3m for both the compositions. The samples were sintered at a temperature of 1300 °C for 6h. The sintered density of the samples was found to be greater than 97%. The temperature dependent dielectric measurement studies reveal that dielectric constant increases with yttrium doping and shows relaxer behavior. A higher dielectric constant and electrical conductivity was observed for the Y-doped sample which fulfill the basic requirement for anode materials of solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

An experiment was carried out in the department of Horticulture, Babasaheb Bhimrao Ambedkar University (BBAU), Lucknow, Uttar Pradesh, India to evaluate the morphological variation of ber fruits collected from widely and naturally grown ber crops inside the main campus of the university. There were 85 morphotypes selected for the study and fruit morphological characters were studied at the departmental laboratory with CRD statistical design and data of various morphotypes were compared at 5% level of significance. The results revealed that the highest fruit weight (15.33 g), fruit length (43.92 mm), fruit width (30.09 mm), fruit volume (14.23ml), pulp weight (14.26g), Pulp thickness (11.12 mm), pulp per cent (92.84%) was observed in B-45 morphotype. These physical characters seemed to be good for customer attractiveness. Considering the morphocharacteristic performance of fruit of 85 ber morphotypes grown in side BBAU campus, it may be concluded that the ber morphotype B-45 could be used for further crop improvement programme for its bigger fruit size, high pulp content. [ABSTRACT FROM AUTHOR]

We present the structural investigation on multiferroic Ba1-xSrxMnO3perovskite manganites with x = 0.50, 0.60, 0.70 and 0.75 synthesized by combustion method. Rietveld refinement of powder X-ray diffraction data reveals the hexagonal structure with space group P63/mmc for all compositions. The unit cell lattice parameters for Ba1-xSrxMnO3decrease monotonically with Sr-substitution on Ba-site. The value of structural tolerance factor decreases from 1.047 for x = 0.50 to 1.018 for x = 0.75. [ABSTRACT FROM PUBLISHER]

This study reports the synthesis of nanocrystalline undoped and europium doped BaWO4:Eu3+ nanophosphors by a mechanical activation process using high energy ball mill (HEBM) technique. The prepared nanophosphors were characterized systematically by Rietveld analysis of the X-ray powder diffraction (XRD) data, Raman spectroscopy, energy dispersive spectroscopy (EDS), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The synthesized nanophosphors were found to possess spherical morphology and small particle sizes ∼25 nm. To explore this material for application in luminescence, detailed time resolved photoluminescence studies were carried out. It was observed that it is a rare breed of phosphor material that exhibits exceptional luminescence properties such as the capability to give high emission output till 5.0 mol% without undergoing quenching and unique property to get excited by mid ultraviolet (MUV) light, near ultraviolet (NUV) light, as well as by visible light such as blue and green. It was also observed that energy transfer primarily takes place from tungstate group of host to Eu3+. In fact energy transfer from the host to Eu3+ becomes more and more efficient with the increasing concentration of Eu3+ ions. Two lifetime values are observed for all europium ion (Eu3+) concentrations, one of the order of 465–650 μs (TS, short lifetime) and the other of the order of 1050–1320 ms (TL, longer lifetime). This reflects the fact that Eu3+ ions occupy two sites; regular symmetric Ba2+ site (S1) and asymmetric site (S2), which will be closer to charge compensating defects. Calculation of Judd–Ofelt parameter illustrated that at all europium concentrations, the local surrounding around it lacked inversion symmetry (asymmetric environment), and the exact point group symmetry around europium ion was found to be C6v. The red purity (intense 5D0–7F2) and high quantum efficiency (78%) of BaWO4:Eu3+ projects it as a new red phosphor for application in white light emitting diodes. [ABSTRACT FROM AUTHOR]

The undoped and Ca-doped BiFeO3 nanoparticles of different particle size were synthesised using sol-gel. Ca-doping induced structural transformation from rhombohedral to orthorhombic phase along with reduced crystallite size due to its smaller ionic radii. Morphological analysis showed increase in particle size from 11 to 50 nm on increasing calcination temperature from 450 to 650 °C. Magnetic and electrical studies revealed enhancement in magnetism as well as dielectric constant and polarisation values with Ca-doping. When the particle size of Ca-doped BiFeO3 nanoparticles was further reduced, these values registered remarkable enhancement. Thermal analysis revealed charge compensation mechanism to occur via formation of oxygen vacancies on doping of Ca2+ ions in BiFeO3 lattice. The decreasing dielectric constant values indicating increasing oxygen vacancies content with particle size also point towards the similar charge compensation mechanism in the particle size varied Ca-doped BiFeO3 nanoparticles. [ABSTRACT FROM AUTHOR]

The undoped and Ca-doped BiFeO3 nanoparticles of different particle size were synthesised using sol-gel. Ca-doping induced structural transformation from rhombohedral to orthorhombic phase along with reduced crystallite size due to its smaller ionic radii. Morphological analysis showed increase in particle size from 11 to 50 nm on increasing calcination temperature from 450 to 650 °C. Magnetic and electrical studies revealed enhancement in magnetism as well as dielectric constant and polarisation values with Ca-doping. When the particle size of Ca-doped BiFeO3 nanoparticles was further reduced, these values registered remarkable enhancement. Thermal analysis revealed charge compensation mechanism to occur via formation of oxygen vacancies on doping of Ca2+ ions in BiFeO3 lattice. The decreasing dielectric constant values indicating increasing oxygen vacancies content with particle size also point towards the similar charge compensation mechanism in the particle size varied Ca-doped BiFeO3 nanoparticles. [ABSTRACT FROM AUTHOR]