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

Weak Ergodicity Breaking in Optical Sensing

The time-integrated intensity transmitted by a laser driven resonator obeys L\'evy's arcsine laws [Ramesh \textit{et al.}, Phys. Rev. Lett. \textit{in press} (2024)]. Here we demonstrate the implications of these laws for optical sensing. We consider the standard goal of resonant optical sensors, namely to report a perturbation to their resonance frequency. In this context, we quantify the sensing precision attained using a finite energy budget combined with time or ensemble averaging of the time-integrated intensity. We find that ensemble averaging outperforms time averaging for short measurement times, but the advantage disappears as the measurement time increases. We explain this behavior in terms of weak ergodicity breaking, arising when the time for the time-integrated intensity to explore the entire phase space diverges but the measurement time remains finite. Evidence that the former time diverges is presented in first passage and return time distributions. Our results are relevant to all types of sensors, in optics and beyond, where stochastic time-integrated fields or intensities are measured to detect an event. In particular, choosing the right averaging strategy can improve sensing precision by orders of magnitude with zero energy cost

DEVELOPMENT AND EVALUATION OF CLOBETASOL–LOADED SOLID LIPID NANOPARTICLES FOR TOPICAL TREATMENT OF PSORIASIS

Objective: The current research was structured to achieve a maximum topical delivery for the drug clobetasol-17-propionate (CP) and to predict the effects of various independent variables like lipid: drug ratio, surfactant, and homogenization time on particulate characters and performance solid lipid nanoparticles (SLNs). Methods: CP loaded SLNs were formulated by Emulsification–Homogenization method and optimized using 33 full factorial designs (Design-Expert software 11.0). Drug loaded SLNs were evaluated for various parameters like particle size, surface charge, polydispersity index, entrapment efficiency, surface morphology, thermal analysis, in vitro drug release through skin (Franz diffusion cell), drug deposition study and stability. Results: The optimized formulation (SLNs) attains a minimal Particle size of 133.3±3.66 nm, Poly dispersibility index of 0.179±0.081, % entrapment efficiency of 78.1±1.11 and Zeta potential of-36.2±0.11mV. Skin permeation study of CP loaded SLNs suspension showed prolonged drug release up to 24h. Maximum drug deposition was obtained after developing the drug into SLNs (48.22µg/ml) when compared to the pure drug (19.12µg/ml). Conclusion: SLNs were promising colloidal particulate carriers by which prolonged drug release and improved skin permeation was achieved for the drug Clobetasol 17- propionate

Determination of thermal constant and development threshold of Bihar hairy caterpillar, Spilarctia obliqua Walker

Effect of six constant temperatures viz., 18±1, 21±1, 24±1, 27±1, 30±1 and 33±10C was studied on the egg hatchability, larval pupal development and adult survival of Spilarctia obliqua. Development rate of egg, larva and pupa gradually increased with increase in temperature, while total developmental period decreased. Mean developmental period of the pest decreased from 93.73 days at 18±10C to 31.20 at 33±10C. The lowest and the highest temperatures at which no development took place were found to be 12±10C and 39±10C, respectively. Regression equations between development rate and temperature were found to be Y= 0.0189 X -0.1998 (R2=0.88) for egg, Y=0.00122 X -0.0248 (R2=0.84) for small larva (1-3rd instar), Y=0.0058 X -0.0675 (R2=0.76) for large larva (4-6th instar), Y=0.0074 X-0.1075 (R2=0.94) for pupa and Y=0.0142 X-0.4363 (R2=0.79) for adults. Developmental threshold were determined to be 10.57, 11.27, 11.55, 15.28 and 10.92oC for egg, small larva, large larva, pupa, and adult respectively with corresponding thermal constant being 52.91, 344.82, 243.90, 142.85 and 70.42 degree days (DD). Thermal constant to complete a generation was found to be 854.90 DD. This was the first studies on this aspects, these estimated thermal thresholds and degree days could be used to predict the S. obliqua activity in the field for their effective management through pest forecasting

Flow regime mapping in gas-liquid flow in micro-channels

Experiments were conducted in a micro-channel with square cross-section with each side being 3 mm.nbsp Gas-liquid flow is employed for determining the flow patterns with water being liquid phase and nitrogen being gas phase.nbsp Over a wide range of gas and liquid velocities the flow patterns were studied using visual inspection technique.nbsp It is found that four types of flow regimes occurred within the range of variables considered in the present study.nbsp These are bubble flow, slug flow, channel flow and transient flow.nbsp A flow regime map is also constructed

Optimal Capacitor Placement - A Bibliometric Survey

In this paper, Bibliometric survey has been carried out on Optimal Capacitor Placement from 1981 to 2021. Scopus database has been used for the analysis. There were total 909 documents found on the topic of Optimal Capacitor placement. The statistical analysis is carried out source-wise, year-wise, area-wise, Country-wise, University wise, author-wise, and based on funding agency. Network analysis is also carried out based on Co-authorship, Co-occurrence, Citation Analysis and Bibliographic coupling. Results are presented. During 2016, there were 77 documents published which is the highest. International Journal of Electrical Power and Energy Systems of Elsevier has published 37 documents during the period of study which is highest under the category of sources. VOSviewer 1.6.16 is the software that is used for statistical analysis and network analysis on the database. It provides a very effective way to analyze the co-authorship, co-occurrences, citations and bibliometric couplings etc. The source for all Tables and figures is www.scopus.com, The data is assessed on 6th June, 2021

Left handed DNA in synthetic and topologically constrained form V DNA and its implications in protein recognition

We have investigated structural transitions in Poly(dG-dC) and Poly(dG-Me5dC) in order to understand the exact role of cations in stabilizing left-handed helical structures in specific sequences and the biological role, if any, of these structures. From a novel temperature dependent Z⇌B transition it has been shown that a minor fluctuation in Na+ concentration at ambient temperature can bring about B to Z transition. For the first time, we have observed a novel Z⇌B⇌Zuble transition in poly(dG-Me5dC) as the Na+ concentration is gradually increased. This suggests that a minor fluctuation in Na+ concentration in conjunction with methylation may transform small stretches of CG sequences from one conformational state to another. These stretches could probably serve as sites for regulation. Supercoiled form V DNA reconstituted from pBR322 and pβG plasmids have been studied as model systems, in order to understand the nature and role of left-handed helical conformation in natural sequences. A large portion of DNA in form V, obtained by reannealing the two complementary singlestranded circles is forced to adopt left-handed double helical structure due to topological constraints (Lk=0). Binding studies with Z-DNA specific antibody and spectroscopic studies confirm the presence of left-handed Z-structure in the pβG and pβR322 form V DNA. Cobalt hexamine chloride, which induces Z-form in Poly(dG-dC) stabilizes the Z-conformation in form V DNA even in the non-alternating purine-pyrimidine sequences. A reverse effect is observed with ethidium bromide. Interestingly, both topoisomerase I and II (from wheat germ) act effectively on form V DNA to give rise to a species having an electrophoretic mobility on agarose gel similar to that of open circular (form II) DNA. Whether this molecule is formed as a result of the left-handed helical segments of form V DNA undergoing a transition to the right-handed B-form during the topoisomerase action remains to be solved

Biochemical Changes during Plantlet Regeneration in Two Accessions of Mucuna pruriens

The genus Mucuna is an important medicinal herb and is extensively used in traditional Indian systems of medicine for various ailments. In vitro culture technique provides an alternative to plant propagation and germplasm conservation. Our aim was to study the biochemical changes occurring during regeneration of shoots (plantlets) from explants of two accessions of Mucuna pruriens, by monitoring the efficiency of nitrogen utilization and changes in levels of some hydrolytic enzymes. A rapid micropropagation system was developed using Murashige and Skoog's (MS) medium supplemented with BAP and IAA combined. In both the accessions, 3.0mg l-1 6-BAP, in combination with 0.2mg l-1 IAA, induced shoot buds and shoot elongation; however for multiple-shoot induction, a slightly higher concentration of cytokinin, i.e., 3.5mg l-16-BAP, in combination with 0.2mg l-1 IAA, was required. Results of the present study confirm an active growth of explants revealed by nitrate assimilation enzymes and hydrolytic enzymes. It is concluded that medium composition, growth regulator combination and culture incubation conditions are all vital in both the accessions of Mucuna pruriens for induction of in vitro plant regeneration