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This work investigates the structural, dielectric, ferroelectric and magnetoelectric coupling properties of (1−x) LiNbO3 − (x) La0.9Na0.1MnO3 with x = 0.1, 0.2, and 0.3 nanocomposites. The composite of ferroelectric material LiNbO3 (LNB) and magnetic material La0.9Na0.1MnO3 (LNMO) was synthesized by the conventional solid-state reaction method. The X-ray diffraction study confirms the formation of the perovskite samples. The crystalline sizes of the samples increased with an increase in x. The improved properties of these composites by the addition of LNMO were investigated through various analysis methods. The composite with x = 0.3 exhibits the highest enhanced values of dielectric permittivity (ε′) and a.c. conductivity with the lowest activation energy Ea = 1.41 eV. The highest magnetoelectric coupling property is also observed for this concentration. This material has wide application in sensors, data storage devices and in pyroelectric applications. [ABSTRACT FROM AUTHOR]

Multiferroic composites offer promising prospects for low-power multifunctional devices. Here, we report the structural, electrical, dielectric, magnetic, and magnetodielectric properties of the multiferroic composite material (1 − x)LiNbO3–xLa0.9Na0.1MnO3 (where x = 0.1, 0.2, and 0.3). Ferroelectric and magnetic phases were synthesized using citrate gel method and the conventional solid-state reaction method was used for the preparation of multiferroic composite material with different mixing percentage values of x. X-ray diffraction was used to confirm the crystalline purity and the crystal structure of the material. The microstructural and elemental composition analyses were done by FE-SEM, X-ray photon spectroscopic (XPS), and EDAX techniques. Dielectric studies and impedance analysis imply the dynamic behavior of charge carriers inside the composites. The maximum value of dielectric constant (5000) was obtained at x = 0.3 for xLa0.9Na0.1MnO3 phase. From impedance analysis method, the equivalent circuit of (1 − x)LiNbO3–xLa0.9Na0.1MnO3 (where x = 0.1, 0.2, and 0.3) composite was found out. The P–E hysteresis loop reveals the ferroelectric nature of the composite. Sample with x = 0.1 of xLa0.9Na0.1MnO3 phase gives the highest values for maximum polarization and remnant polarization. The enhanced magnetic properties of the composite material were substantiated with M–H hysteresis loop measurements. The magnetodielectric and magnetoelectric coupling measurements revealed the presence of ferroelectric and ferromagnetic coupling nature of the composite material. From all these analyses, the multiferroic composites with the composition x = 0.3(La0.9Na0.1MnO3) yields the maximum ferroelectric and magnetic coupling behavior. So, this composite material has wide applications in multifunctional nano devices. [ABSTRACT FROM AUTHOR]

The influence of non-magnetic Ti doping at the Mn site on magnetoresistance and thermopower properties of Sm0.6Sr0.4MnO3 (Sm0.6Sr0.4Mn1-xTixO3, x = 0, 0.1 and 0.15 denoted by SMO, STMO0.1 and STMO0.15 respectively) prepared by solid-state reaction method is investigated. All three samples exhibit metal–insulator transition. STMO0.15 has a sudden drop of resistivity around 100 K. At low temperatures, the magnetoresistances of the samples get increased with Ti doping. All samples have negative thermoelectric power (TEP) at room temperature. Both high-temperature resistivity and TEP of the samples are successfully analyzed using the Variable Range hopping (VRH) model. Power factor, which determines the quality of a TEP material, is comparatively high for 15% Ti-doped sample STMO0.15 at room temperature. [ABSTRACT FROM AUTHOR]

In this work, we describe systematic studies on multiferroic composites (1−x) Bi Fe0.9Mn0.1O3/xLa0.7Sr0.3MnO3 (x = 0, 0.05, 0.1) synthesized via solid-state reaction route. Structural, dielectric, impedance, magnetic, magnetoelectric (ME), and optical properties were investigated at room temperature. X-ray diffraction (XRD) patterns show peaks corresponding to both Bi Fe0.9Mn0.1O3 (BMFO) and La 0.7Sr 0.3MnO3 (LSMO) phases and confirms the formation of composites. The frequency responses of dielectric constant and AC conductivity of the samples enhances with increasing content of LSMO and Nyquist plots have been investigated at room temperature. M–H loops at room temperature show enhancement in magnetization values on the addition of LSMO. Furthermore, the ME responses of the samples were analyzed and ME coupling coefficients were calculated for all the samples. Optical band gap and luminescence properties of the materials suggest their applications in optoelectronic devices. [ABSTRACT FROM AUTHOR]

This paper presents a systematic study of room temperature magnetoelectric properties of lead-free (1 − x) Bi0.9La0.1FeO3/xLa0.7Sr0.3MnO3 (x = 0, 0.1, 0.2) composites synthesized via solid-state reaction route. We investigated the crystal structure, morphology, elemental presence, dielectric parameters, and electric polarization properties. Magnetization versus field study shows an enhancement in magnetization values as we add La0.7Sr0.3MnO3 (LSMO) to the Bi0.9La0.1FeO3 (BLFO) samples. The magnetoelectric (ME) coupling coefficient increases from 10.21 to 23.16 mVcm−1Oe−1 as the concentration of LSMO varies from x = 0 to 0.2. The observed linear dependence of voltage generation with modulating AC field point toward the direct application of the material in a variety of next-generation low power consuming memory devices, spintronics, sensors, etc. [ABSTRACT FROM AUTHOR]

Introduction: Leptospirosis and dengue are two significant public health concerns in tropical and subtropical regions, often resulting in severe forms of disease and fatality. This study addresses the pressing public health issues of leptospirosis and dengue in the Dakshina Kannada district of Karnataka, India. Both diseases pose significant health risks and are relatively understudied in this region, making it essential to investigate their prevalence and clinical presentations for targeted healthcare planning., Aim: The primary aim is to determine the frequency of leptospirosis and dengue among febrile illness cases to understand the epidemiological patterns and assess co-infection rates in Dakshina Kannada., Method: Between 2020 and 2021, serum samples suspected of leptospirosis were tested using IgM ELISA (n = 1629) and the Microscopic Agglutination Test (MAT) (n = 92) for leptospirosis, while dengue was tested using NS1Ag and IgM antibodies ELISA (n = 1415). Data were collected through medical records and patient interviews. Seasonal trends, gender, and age distributions were analyzed., Result: The study found a significant prevalence of leptospirosis (21 %) and dengue (10 %) among febrile illness cases in the study area, with a 1.3 % co-infection rate. Clinically, fever was common to both diseases, but leptospirosis also frequently exhibited symptoms such as abdominal pain, myalgia, and jaundice. MAT screening revealed a predominance of anti-leptospiral antibodies against the Djasiman, Pyrogenes, Hurstbridge, Hebdomadis, and Grippotyphosa serogroups in Dakshina Kannada., Conclusion: The study highlights the urgent need for focused public health interventions, improved diagnostic tools, and targeted epidemiological studies to manage these diseases. The findings underscore the necessity of enhancing diagnostic capabilities and public health awareness, particularly considering the significant health risks posed by leptospirosis and dengue in the region., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Indian Association of Medical Microbiologists. Published by Elsevier B.V. All rights reserved.)