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SmCo5/Co core-shell nanoparticles are studied for their ability to improve magnetic properties like coercivity and exchange-bias effects. The core-shell structure helps enhance these properties by allowing better control over the magnetic behaviour of the core, shell, and their interface. These nanoparticles can maintain strong magnetization, high coercivity, and improved energy efficiency. The structure allows for adjustable magnetic properties, giving insights into the core, shell, and their interactions effect on the overall magnetism. We use atomistic magnetic simulations with VAMPIRE software to study the magnetization reversal, coercivity, and Curie temperature in two different combination of exchange-coupled bi-magnetic hard/soft ferromagnetic core/shell nanoparticle. In the first configuration, SmCo5 is the hard magnetic core and Co is the soft magnetic shell. The core size (dc) varies from 0 to 4 nm, while the overall particle size stays around 5 nm. The results show that changing the shell thickness affects the microscopic interface pinning mechanism. Whether SmCo5 is the core with Co as the shell, or vice versa, the coercivity shows little change with variations in shell thickness, but it increases significantly compared to individual Co or SmCo5 nanoparticles. The findings confirm that the core-shell structure depends on the materials, core size, and temperature. We also investigate how the finite-size effect influences the Curie temperature of SmCo5 and Co nanoparticles using M-T graphs. The results show that the maximum energy product (BH)max strongly depends on core size. The SmCo5/Co core-shell nanoparticle combination boosts magnetic performance by utilizing SmCo5's high magnetic strength for permanent magnets and the Co shell's thermal stability for enhanced magnetization. This synergy makes them suitable for applications in permanent magnets, recording media, and biomedical uses. [ABSTRACT FROM AUTHOR]

Molecular docking and dynamics simulation analysis of PDE5 inhibitor candidates for erectile dysfunction treatment compounds compared to Sildenafil, a PDE5 inhibitor. M ATERIALS AND METHODS: Autodock Vina v. 1.2.5 software was used to dock the protein and each ligand individually. Molecular dynamics simulations assessed the binding affinity of two compounds to the Phosphodiesterase 5A1 (PDE5 A1) enzyme and were carried out using GROMACS 2022.2 RESULTS: Boesenbergin A exhibited the highest affinity at -8.8 kcal/mol, followed by Ginkolide B at -8.5 kcal/mol, Sildenafil at -8.1 kcal/mol, Montanol at -7.8 kcal/mol, Beta-sitosterol at -7.1 kcal/mol, and Eugenol acetate at -6.9 kcal/mol, ranked in descending order. As a result of molecular docking studies, molecular dynamic simulations were performed for Boesenbergin A, which has the highest affinity, and Sildenafil, which is the standard molecule. CONCLUSIONS: Among the two ligands tested, Boesenbergin A exhibited superior binding affinity, surpassing even the standard molecule, Sildenafil. This suggests their potential for modulating enzyme activity and potential relevance in erectile dysfunction treatment. [ABSTRACT FROM AUTHOR]

FeRh 0.8 Pd 0.2 is known to exhibit near room-temperature first-order antiferromagnetic (AF)–ferromagnetic (FM) transition, typical of chemically ordered FeRh system. In addition, it is also reported to show martensitic transition at a lower temperature. In this work, the effect of sample history on transition temperature (T t) and the magnetocaloric effect (MCE) have been studied. The experimentally determined MCE parameters across FM to AF transition induced either by isothermal magnetic field sweep or by temperature sweep showed a large isothermal change in entropy around room temperature, i.e., 14 J/kg K for 50 kOe magnetic field change, whereas MCE corresponding to AF–FM transition depends on cooling history. Our study shows that in the presence of martensite phase, the peak value of MCE is shifted to higher temperatures but with significantly reduced magnitude. [ABSTRACT FROM AUTHOR]

We report a detailed study on the orientation dependent growth characteristics, electronic structure, transport, magnetic, and vibrational excitations in atomically flat interfaces of [ La 0.7 Sr 0.3 MnO 3 / LaNiO 3 ] 10 superlattices (SLs) coherently grown on (001/011/111)- SrTiO 3 substrates by the pulsed laser deposition technique. X-ray reflectometry confirms the periodic superlattice stacks from the Kiessig interference fringes and well-defined even interfaces between the nickelate and manganite layers. A complex local atomic environment across the interfaces was noticed, yet trivalent La, divalent Sr, and mixed valent Ni 2 + / 3 + and Mn 3 + / 4 + electronic states prevail at the core level with enhanced relative intensity ratio of the Mn ions in the superlattices grown on (111) oriented SrTiO 3 substrates as compared to those grown on (001) and (011) oriented SrTiO 3. The temperature (5 ≤ T ≤ 300 K) dependence of electrical resistivity ρ (T) analysis reveals 3D variable range hopping model [ ρ (T) = ρ 0 exp ⁡ (T 0 / T) (1 / 4) ] with large magnitude of hopping energies (≥ 40 meV) for the SL-111 system associated with the high energy gap developed by the accumulation of disorderness in the individual constituents of polar layers. Moreover, all SL systems exhibit reduced ferromagnetic ordering temperatures (67 ≤ T C ≤ 110 K) with a low-temperature anomaly (11.4 ≤ T ∗ ≤ 22 K) and a substantial enhancement in the effective exchange interaction ( J e f f ∼ 3.52 meV) having altered ground state-spin configuration S ∼ 1 / 2 different from S = 3 / 2 of La 0.75 Sr 0.25 MnO 3. Nevertheless, the SL-011 system exhibits large anisotropy field H K ∼ 18 kOe and cubic anisotropy constant K 1 ∼ 9.3 × 10 3 J / m 3 in comparison to the other two orientations. The second order two-phonon interaction driven by the local polaronic distortion causes significant changes in the vibrational excitations of the investigated system. Nonetheless, most of the Raman modes follow the substrate-induced, highly oriented epitaxial growth pattern except for two modes ν 4 (326 cm − 1 ) and ν 8 (728 cm − 1 ), which slightly differ in the case of SL-111 superlattices. [ABSTRACT FROM AUTHOR]

The study aimed to measure indoor concentrations of radon, thoron, and their progeny in populated areas across seven locations in Muzaffarnagar using dosimeters, DTPS, and DRPS. The data collected over one year across four quarters revealed significant variability in concentration between locations and seasons. The highest average concentration of radon was found in Charthawal from November to January (92.3 Bq/m³), while the highest average concentration of thoron was observed in Mansoorpur from August to October (84.9 Bq/m³). The average concentration of radon progeny was highest in Rohana from November to January (24.7 Bq/m³), while the average concentration of thoron progeny was highest in Tirupadi from August to October (2.9 Bq/m³). Significant variations were observed in the concentration of radon, thoron, and their progeny between locations, which can be due to geological differences, building materials, and ventilation rates. The data also revealed seasonal variation, with November to January having the highest average concentrations of radon, thoron, and their progeny. The total effective dose of radon + EERC varied considerably across locations, with Tirupadi having the highest total effective dose of 0.89 mSv/year, and Muzaffarnagar having the lowest total effective dose of 0.62 mSv/year and similarly for thoron + EETC having the highest of 0.42 mSv/ year. the lowest of 0.07 mSv/ year in Rohana. [ABSTRACT FROM AUTHOR]

Resveratrol is a polyphenolic phytocompound known to possess anxiolytic-like effects but its impact on central gammaaminobutyric acid (GABA) modulation has never been explored. The purpose of this study was to analyze the anxiolytic-like effects of resveratrol alone and in combination with rufinamide, an antiepileptic drug which has never been studied for its anxiolytic potential. The BALB/c mice were tested in a battery of behavior testing after administration of resveratrol (50 mg/kg) and rufinamide (50 mg/kg) alone and in combination. Moreover, molecular docking studies were also carried out to understand the interaction of resveratrol and rufinamide with GABA aminotransferase, GABA receptor and GABA-A transporter type 1. Resveratrol alone exerted notable anxiolytic-like effects and improved outcomes in few experiments but rufinamide alone did not yield any beneficial outcomes. However, the animal co-administered with resveratrol and rufinamide behaved exceptionally well (p<0.05) and preferred open, illuminated and exposed areas of open field, light/dark and elevated plus maze. Further, these animals showed reduced anxiety towards anxiogenic stimuli i.e. holes and marbles in hole board and marble bury tests, respectively. Resveratrol and rufinamide showed moderate to strong binding affinities with GABA proteins, indicating the potential to treat anxiety-like neurological disorders. Moreover, resveratrol and rufinamide were analyzed using molecular docking to determine their interaction with GABA receptors, transporters, and transaminase. The results suggest that their anxiolytic-like effects may be due to inhibiting GABA reuptake transporter 1 protein, leading to increased synaptic levels of GABA neurotransmitter, as seen in stable molecular dynamics results with the 7SK2 GABA transporter protein. [ABSTRACT FROM AUTHOR]

The importance of lightning has long been recognized from the point of view of climate‐related phenomena. However, the detailed investigation of lightning on global scales is currently hindered by the incomplete and spatially uneven detection efficiency of ground‐based global lightning detection networks and by the restricted spatio‐temporal coverage of satellite observations. We are developing different methods for investigating global lightning activity based on Schumann resonance (SR) measurements. SRs are global electromagnetic resonances of the Earth‐ionosphere cavity maintained by the vertical component of lightning. Since charge separation in thunderstorms is gravity‐driven, charge is typically separated vertically in thunderclouds, so every lightning flash contributes to the measured SR field. This circumstance makes SR measurements very suitable for climate‐related investigations. In this study, 19 days of global lightning activity in January 2019 are analyzed based on SR intensity records from 18 SR stations and the results are compared with independent lightning observations provided by ground‐based (WWLLN, GLD360, and ENTLN) and satellite‐based (GLM, LIS/OTD) global lightning detection. Daily average SR intensity records from different stations exhibit strong similarity in the investigated time interval. The inferred intensity of global lightning activity varies by a factor of 2–3 on the time scale of 3–5 days which we attribute to continental‐scale temperature changes related to cold air outbreaks from polar regions. While our results demonstrate that the SR phenomenon is a powerful tool to investigate global lightning, it is also clear that currently available technology limits the detailed quantitative evaluation of lightning activity on continental scales. Plain Language Summary: Lightning is recognized as a climate variable indicating the changing climate of the Earth. Surface temperature changes on the order of 1°C can result in a significant change in lightning frequency. Lightning activity is monitored on a global scale by satellites and by ground‐based global lightning detection networks. However, the detection efficiency of these available technologies is limited which restricts the investigation of global lightning activity especially on the day‐to‐day time scale. In this study, we propose an alternative method to monitor day‐to‐day changes in global lightning activity based on Schumann resonance measurements and thus we compare SR‐based observations with available global lightning monitoring techniques. We show that the overall intensity of global lightning activity can vary considerably (by a factor of 2–3) within a few days, further motivating our efforts to monitor such changes and understand their causes. It is also clear from our study that new methods are needed to quantitatively characterize continental‐scale lightning activity. Key Points: Daily average Schumann resonance intensity is a quasi‐global invariant quantity that shows good agreement with global daily stroke rates and thunder hoursGlobal lightning activity can vary by a factor of 2–3 on a 3–5 day timescale which could be attributed to cold air outbreaksCurrently available technology does not allow the detailed quantitative evaluation of lightning activity on continental scales [ABSTRACT FROM AUTHOR]

The effect of partial substitution of Ge for Sb on the first-order ferrimagnetic (FRI)–antiferromagnetic (AFM) transition in Mn 2 Sb has been studied. It shows that the transition temperature (T t) can be tuned between 119 K and 271 K by substituting 2.5%–10% Ge at Sb sites in Mn 2 Sb. The variation of density of state at the Fermi level N(E f) with Ge substitution shows that dN(E)/dE is positive at E f in the AFM state. With the application of a magnetic field, T t shifts to low temperature, which results in a giant negative magnetoresistance (MR) reaching a value of 70% for 2.5% substitution. Our results show that FRI to AFM transformation during cooling stops around 35 K, even though it remains incomplete. This, along with the nonmonotonic variation of lower critical field, open loop in isothermal MR, and increasing difference in zero field cooled warming and field cooled warming resistivity with increasing magnetic field, shows that the FRI to AFM transition is kinetically arrested in the case of 2.5% Ge substitution. [ABSTRACT FROM AUTHOR]