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In the present study, NdFeO3 (NFO), Nd(0.9)Ba(0.1)FeO3 (NBFO), NdFe(0.9)Mn(0.1)O3 (NFMO) and Nd(0.9)Ba(0.1)Fe(0.9)Mn(0.1)O3 (NBFMO) were successfully synthesized using citrate sol–gel chemical route. X-ray diffraction (XRD) patterns confirm the formation of orthorhombic perovskite structure with space group Pbnm and are further complemented by the Rietveld refinement. Scherrer's formula as well as Williamson–Hall (W–H) plot was used to calculate average crystallite size of the prepared samples. Further, morphological investigations were carried out using SEM imaging and EDX spectroscopy. Dielectric properties including frequency dependence of dielectric permittivity (ε), tangent loss (tan δ) and electrical conductivity (σ) of all the samples were analysed at different temperature ranges from 300 to 623 K over a frequency range from 100 Hz to 1 MHz. It was found that the ε decreases with the increase in frequency. Optical properties were investigated using the UV–visible spectroscopy and the Tauc's plot was employed on the absorbance spectra for calculating the energy band gap. It was found that the band gap decreases as the dopants are inserted in the lattice of NFO. Magneto-dielectric properties were analysed by using varying magnetic field from 0 to 2 T. These samples could serve as the properties of materials with potential applications in logic gate, data storage, switches and sensors. [ABSTRACT FROM AUTHOR]

Sol–gel synthesis method was employed to fabricate nanocomposites of (Dy, Hf) co-doped 0.8BiFeO3–0.2CaTiO3 (Bi0.75Dy0.05Fe0.80O3–Ca0.20Ti0.18Hf0.02O3/BDyFO–CTHfO composite). Structural analysis, utilizing X-ray diffraction and Rietveld refinement with Fullprof software, confirmed a rhombohedral structure with space group R3c and an orthorhombic structure with Pnma space group. Particle size determined through Scherrer's formula was ~15 nm. FESEM studies revealed irregular and slightly dense inhomogeneous grains. Dielectric permittivity (ε) and tangent loss (tan δ) were investigated as functions of frequency from 100 Hz to 1 MHz at different temperatures ranging from 303 to 663 K. The dielectric dispersion behaviour was attributed to Maxwell–Wagner-type polarization, with a notable anomaly in dielectric permittivity observed near the magnetic phase transition temperature (TN ~ 643 K) of BiFeO3. Frequency-dependent ac conductivity exhibited low-frequency dispersion following Jonscher's power law. Presence of ferroelectricity was confirmed by the polarization–electric field (PE) loop. Magneto-dielectric characteristics were assessed in a frequency range of 100 Hz–1 MHz under a magnetic field of 0–2 Tesla. Impedance spectroscopy highlighted electrical properties, distinguishing grain and grain boundary contributions via Nyquist plot with respect to the magnetic field. The BDyFO–CTHfO composite demonstrated significant absorption and ~ 25% transmittance in the visible spectrum. The material exhibited a band gap (Eg) of 1.97 eV, suggesting potential applications in ultrafast optoelectronic devices. [ABSTRACT FROM AUTHOR]

Cobalt disulfide (CoS2) is a highly sophisticated metal chalcogenide that has garnered significant attention due to its distinctive properties such as its electrical, optical, catalytic, and magnetic capabilities and potential for use in a range of applications. In this work, pure CoS2 nanoparticles were synthesized using the economical and facile hydrothermal method. The X-Ray diffraction (XRD) method was used to characterize the synthesized sample, confirming that it has a cubic crystal structure with space group P a −3. The Debye-Scherrer's formula was implemented to determine the average crystallite size of nanoparticles and found to be 24.24 nm. Through the use of Field Emission Scanning Electron Microscopy (FESEM), the morphology and effective grain size of the obtained sample was determined. FTIR spectrophotometry was used to examine the vibrational stretching of the various bonds in CoS2. UV-Vis spectroscopy is employed to measure the optical property of the sample. The optical bandgap calculated from the Tauc Plot is around 1.90 eV reflecting the presence of photovoltaic properties in the sample. The change in dielectric permittivity and loss have been observed for the sample in the frequency range of 100 Hz to 10KHz at different temperatures between 303K and 423K. The frequency-dependent electrical conductivity of CoS2 is also explained. The observations revealed the presence of unique electrical and structural properties in the synthesized sample. [ABSTRACT FROM AUTHOR]

CaCu3Ti4O12 (CCTO) nanomaterials were synthesized using the low-cost facile sol-gel technique. X-ray diffraction (XRD) patterns confirmed the cubic structure of the prepared sample. Scherrer's formula and the W-H (Williamson-Hall) plot was used to calculated the average crystallite size of the prepared sample and it was found to be 27 nm and 31.3 nm, respectively, while the strain created in the lattice is 5.008 × 10−4. Based on the absorbance plot, the band-gap (Eg) of the sample was determined using Tauc's plot and it was found out to be 2.74 eV. The frequency dependence of dielectric permittivity (ε) and tangent loss (tan δ) of CCTO was analyzed at different temperature range from 300 K to 663 K over a frequency range from 10 Hz to 1 MHz. ε and tan δ decrease monotonically in entire frequency range and an anomalous frequency-dependent behavior was observed at different temperatures. High ε (in the range of 104) was found out at lower frequency range. Electrical conductivity was also analyzed in range of frequencies and temperature, it was found out that in higher region of frequency conductivity slightly increases. The room temperature values of ε, tanδ and conductivity was 7.5 × 103, 1.5 and 0.4 × 10−5 Ω−1 m−1, respectively. The reduction in Eg is achieved which was the major concern in this work. Furthermore, we have extensively studied the ε along with tan δ and ac conductivity for electronic application usage. According to these observations, CCTO is particularly prepared so that it could be suitable for microelectronic applications due to its high ε and low tan δ. [ABSTRACT FROM AUTHOR]

The CaSn0.95Mn0.05O3 (CSMO) was produced by using the sol-gel wet chemical process. The structural composition was examined using an X-ray diffraction (XRD) pattern, and the presence of an orthorhombic structure with the space group Pbnm was confirmed by Rietveld refinement. At different temperatures between 300 K and 773 K, the dielectric permittivity (ε), tangent losses (tanδ), and electrical conductivity of CSMO has been measured as a function of frequency from 100 Hz to 1 MHz.Dielectric permittivity (ε) is found to be independent of temperature up to 400K and very low tangent loss. Jonscher's power law in the material's frequency-dependent ac conductivity shows its semiconductor nature. Optical band gap of CSMO was observed by using UV-vis.absorption spectra. The optical band gap of CSMO, which was determined using Tauc plot measurements to be 2.42 eV, suggests that the sample is a semiconductor. The Arrhenius model is employed to perform an analysis of the dc conductivity of the material concerning both frequency and temperature. As a result of its semiconductivity, stable dielectric constant, and low tangent loss, CSMO is a suitable material for thermally stable capacitors, semiconductor devices, UV filter and UV detectors. [ABSTRACT FROM AUTHOR]

Sol-gel method is used to synthesize the Bi0.90Dy0.10FeO3-BaTi0.95Hf0.05O3 (BDyFO-BTHfO composite) multiferroic composite material. The structural formation was examined utilizing an X-ray diffraction (XRD) pattern preceded by Rietveld refinement utilizing the FULLPROF programme to confirm the presence of tetragonal and partially rhombohedral structures having space group P4mm and R3c, respectively. The dielectric characteristics of the BDyFO-BTHfO composite have been measured with respect to frequency (100 Hz to 1 MHz) and temperature (RT to 663K). Dielectric permittivity (ε) shows low-frequency dispersion which can be addressed by Maxwell-Wanger-type interfacial polarization. The synthesized composite material exhibits a negative magneto-dielectric (MD) effect when a magnetic field is operated (0.0 T to 2.0 T) and the obtained values are −9.61% and −19.68% for the ε and tanδ, respectively, at 1 kHz. The contribution of the grains, grain boundaries and electrode effects on the resistive characteristics of the samples was evaluated using comprehensive impedance spectroscopy using a Nyquist plot. The band gap (Eg) absorption of the synthesized sample was determined using Tauc's formula and found to be 2.05 eV. The BDyFO-BTHfO composite has improved magneto-dielectric, magneto impedance, and optical properties that support their potential usage in microelectronics, energy storage devices, and optoelectronic devices. [ABSTRACT FROM AUTHOR]

Background: In India, the cosmetics industry has expanded significantly because of changing lifestyles and increased awareness. In terms of earning the most money from the personal care and cosmetics industry in 2021, India is ranked fourth globally. Many cosmetics sold in India include ingredients that cannot be used on humans. Objective: To assess knowledge, attitudes, and practice toward the uses of cosmetics and cosmetovigilance in India. Methods: A cross‑sectional study was conducted, from April to May 2022, among the general population living in the Delhi NCR region, India. Study questionnaires (printed and survey link) were distributed in public as well as at workplaces for the survey. Results: Around 268 (54.78%) females and 223 (45.21%) males participated in the survey. Amongst the total respondents ‑ 407 (83%) agreed that they are using cosmetic products on a daily basis, females 229 (85.44%), being the majority users compared to males 178 (80%), with a significant P value = 0.011. Most of the people reported side effects of shampoos ‑ 7.13% (hair fall, hair thinning, dryness of the scalp, itching), followed by allergic reactions to moisturizers ‑ 5.70%. Conclusion: Because of the right safety and effectiveness mentorship of cosmetics, regulatory agencies and stakeholders should adopt this broadly. Cosmetovigilance needs to be put into practice. [ABSTRACT FROM AUTHOR]

We report the synthesis and characterization of low leakage and large magneto-dielectric (MD) sol-gel derived Bi1−xCaxFeO3 (x = 0, 5%, 10%) [BCFO] nanocrystalline multiferroic ceramics. The X-ray diffraction (XRD) data analysis revealed a rhombohedral structure for pure BiFeO3 (BFO) and 5% Ca-doped BFO, as well as a mixture of rhombohedral and orthorhombic (R3c + Pbnm) structures for 10% Ca-doped BFO. The dielectric permittivity (ε) data exhibit anomalous dielectric behavior near the magnetic phase transition temperature of BFO, supporting the presence of the MD effect at room temperature. At room temperature, 10% Ca-doped BFO exhibits a strong magneto-dielectric coupling (MD) and shows positive MD effects. The frequency-dependent ac conductivity follows modified Jonscher’s power law. Incorporating Ca reduces the leakage current by five orders of magnitude (for x = 10%) and significantly improves the MD coupling. The optical band gap also significantly reduced from 2.24 to 1.70 eV after calcium substitution, which makes it suitable for use in photovoltaic applications. [ABSTRACT FROM AUTHOR]

The present work reports the synthesis of nanostructured thin films on glass substrate by dip coating. The thickness of thin film was varied by varying the no. of dips of glass substrate in the aqueous solution of Ca(NO3)2⋅4H2O and NaOH. Deposited films were studied by the X‐Ray Diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM), Fourier Transform Infrared Spectroscopy (FTIR), and Ultraviolet‐visible (UV‐Vis) spectroscopy techniques. The thickness of film was increased almost linearly with number of dips. Accordingly, the nanocrystalline size and band gap was varied. Interestingly the nanoflower like structure of calcite thin films was observed in FESEM and that varied with the thickness of film. The calcite thin film formation was discussed in terms of reactivity due to nanostructure and surface structure was discussed in terms of nucleation and growth of film on the substrate. Finally, the implications of these results in terms of microstructurally tuned nano calcite thin films development for prospective futuristic industrial applications are highlighted. [ABSTRACT FROM AUTHOR]

0.7Bi0.99Nd0.01Fe0.99(Co, Ti)0.01O3-0.3CaTiO3 (BNFCTO-CaTO) composite was prepared by using sol-gel method. The structural formation was investigated using the XRD pattern, which confirms the presence of distorted rhombohedral structure with space group R3c and the superlattice orthorhombic crystal structure with space group Pbmn. The dielectric behavior of BNFCTO-CaTO has been studied within the frequency range of 100 Hz to 1 MHz from 300 K to 773 K. The sample shows dielectric dispersion in low frequency region that can be explained by Maxwell-Wagner type interfacial polarization. The temperature-dependent dielectric plot shows an anomaly near to magnetic transition temperature (TN) of BiFeO3 and shows relaxor behavior. Furthermore, BNFCTO-CaTO shows a strong magneto-dielectric coupling effect at room temperature. [ABSTRACT FROM AUTHOR]

Objective: To assess the distribution pattern of Langerhans cells in oral lichen planus using adenosine triphosphatase (ATPase) histochemistry and to correlate this with the duration of symptoms. Method and Materials: Included were fresh unfixed tissues from previously untreated cases that were clinically and histologically diagnosed as oral lichen planus (n = 18). Healthy oral mucosal tissues were used as controls (n = 5). ATPase activity in the Langerhans cells from the tissue samples was assessed by enzyme histochemistry. Results: The difference in the distribution pattern of Langerhans cells in the superficial and basal half of the epithelium in both the lesional and control tissue was significant (P < .001, Mann-Whitney U test). With an increase in duration of symptoms, the median migration of cells from superficial position to the basal half was significant (P = .001, Kruskal-Wallis test). A negative correlation (Pearson correlation coefficient) was seen between duration of symptoms and migration of cells. Conclusion: The initial increase in the number of Langerhans cells in the lesional tissues compared to controls suggests that these cells are critically required for both the initiation and progression of the mucosal immune response in oral lichen planus. Variation in their number and distribution bear clinical importance as objective assessment of long-standing lesions could be made with reference to treatment planning. [ABSTRACT FROM AUTHOR]

Invasive fungal infections caused by the members of Mucoromycotina (mucormycosis) are relatively rare but have increased in the last years. These aggressive and highly destructive infections fail to induce disease in most immunocompetent persons but can do so in those with impaired host defenses. Compared to other fungal pathogens, such as Aspergillus fumigatus or Candida albicans, only little is known so far on the fungal properties leading to successful infection and host immune response to the various representatives of the Mucorales. This article explains the new nomenclature, clinical manifestations, risk factors and focuses on virulence traits associated with mucormycosis. Early diagnosis and prompt treatment can reduce the mortality and morbidity of this lethal fungal infection. [ABSTRACT FROM AUTHOR]

The CaSn0.95Mn0.05O3 (CSMO) was produced by using the sol-gel wet chemical process. The structural composition was examined using an X-ray diffraction (XRD) pattern, and the presence of an orthorhombic structure with the space group Pbnm was confirmed by Rietveld refinement. At different temperatures between 300 K and 773 K, the dielectric permittivity (ε), tangent losses (tanδ), and electrical conductivity of CSMO has been measured as a function of frequency from 100 Hz to 1 MHz.Dielectric permittivity (ε) is found to be independent of temperature up to 400K and very low tangent loss. Jonscher's power law in the material's frequency-dependent ac conductivity shows its semiconductor nature. Optical band gap of CSMO was observed by using UV-vis.absorption spectra. The optical band gap of CSMO, which was determined using Tauc plot measurements to be 2.42 eV, suggests that the sample is a semiconductor. The Arrhenius model is employed to perform an analysis of the dc conductivity of the material concerning both frequency and temperature. As a result of its semiconductivity, stable dielectric constant, and low tangent loss, CSMO is a suitable material for thermally stable capacitors, semiconductor devices, UV filter and UV detectors. [ABSTRACT FROM AUTHOR]

Introduction: Odontomes are most common type of odontogenic tumors. They are generally asymptomatic and discovered on routine radiographic examinations. Morphological classification of odontomes can be doneas complex and compound odontomes. Here we document a case of a 15 year old boy who attended our dental department with apparent malocclusions. A panoramic radiograph revealed presence of multiple radio opaque masses in maxillary as well as mandibular arches. These structures were seen associated with impacted permanent teeth. The histopathological examination confirmed the diagnosis of them as being complex odontomes. [ABSTRACT FROM AUTHOR]

Introduction: 0.9 – 12.1% of all cases of ameloblastoma account to be Desmoplastic Ameloblastoma (DA). The presentation of the tumor is often similar to benign fibro-osseous lesions both clinically as well as radiographically. Histologically, DA is made up of small nests and strands of odontogenic epithelium which seem to be compressed by the highly collagenized stroma. We report a case of DA in a 44-year-old female with a mildly painful swelling in the anterior region of mandible. The lesion had a multilocular appearance on both panoramic radiographs as well as in the computed tomography scan. Histologically, the lesion was confirmed to be a case of DA. Regardless of the fact that DA is a rare entity, its aggressive nature binds the clinician to be cautious enough to include DA in the differential diagnosis of any lesion/growth clinically and radiographically mimicking a benign fibro osseous lesion. [ABSTRACT FROM AUTHOR]

Mucormycosis is a rare, often fatal opportunistic infection caused by a saprophytic fungus belonging to a class of Phycomycetes. It is characterized by its unrelenting progression towards vital organs with marked propensity towards arterial wall by direct extension producing vascular thrombosis leading to ischaemic necrosis. In normal circumstances the saprophytes are not pathogenic but represent opportunist-requiring impairments in patient's resistance to disease. If not treated the disease may prove fatal. We report a case of Mucormycosis with extensive necrosis of the maxilla in a 57-year-old patient suffering from uncontrolled diabetes with ketoacidosis.