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Oral leukoplakia (OL), an oral potentially malignant disorder begins with a hyperplastic/hyperkeratotic stage at which no genome-scale somatic single nucleotide variant profiles have been described so far. We performed exome sequencing of five cases at this stage with no evidence of dysplasia to identify genetic alterations (exon-level copy number alterations, indels, and single nucleotide variants), their association with transcript levels and relationship with oral cancer susceptibility. Pathway enrichment analysis of genes associated with tobacco chewing and age-related mutation signatures, transcripts with variants predicted to be functionally damaging and those with significantly altered levels have all indicated the involvement of focal adhesion, ECM–receptor interactions, regulation of cytoskeleton and DNA repair. Two novel mutations identified in FAT1 tumor suppressor gene were associated with decreased transcript levels. In addition, 16 expressed cancer driver genes contained functionally damaging variants. Many of the affected genes were also reported in dysplastic OL lesions. The presence of variants in cancer driver genes and those shared with oral dysplasias possibly provide a basis for further progression and increased susceptibility to oral cancer.

Here we report the evidence of an additional magnetic ordering and frequency dispersive magneto-dielectric (MD) permittivity besides multiferroic behavior in Te4+ (S = 0) doped FeVO4. Two antiferromagnetic transitions similar to FeVO4 at ∼21.86 K (T N 1 ) and 16.03 K (T N 2 ) were observed in all samples. An additional novel defect clusters based magnetic ordering at relatively higher temperature (T A M O ) ∼ 203 K is also observed from the magnetization. Evaluated magnetic moments show systematic decrease and the magnetic frustration factors show an increase with the increasing of Te4+ (S = 0) content. MD studies show stable ferroelectric ordering at spiral magnetic transition (T N 2 ) and the multiferroic order persists to the largest doping of Te (x = 0.10). The MD studies also reveal a magneto-capacitive (MC) behavior at T A M O (∼203 K) with a high dielectric constant and loss, and the possible reason for the magnetic ordering and MC behavior is ascribed to short range magnetic clustering arising out of defect based mechanisms. Mössbauer spectroscopic studies confirm local structural correlation with magnetic and ferroelectric ordering.

Introduction: Endoscopic repair of Cerebrospinal fluid (CSF) rhinorrhea has been the most popular and the most accepted among the Otorhinolaryngologists. The advancement in the endoscopes enable surgeons to manage cerebrospinal fluid rhinorrhea adequately with good result. Objective: The aim of this study was to evaluate the outcome of endoscopic CSF rhinorrhea repair with multilayer grafts. Outcome was identified in terms of postoperative complications like infection (mainly meningitis), nasal bleeding, graft failure and CSF leak, revision surgery. Methodology: A retrospective prospective study was conducted in 21 patients who had undergone endoscopic CSF rhinorrhea repair with use of multilayer grafts in a period of January 2016 to December 2018 in Department of ENT and Head and Neck Surgery in MAA ENT HOSPITAL, HYDERABAD, INDIA. All the patients were diagnosed according to history, clinical examination, diagnostic nasal endoscopy, CSF fluid analysis and radiological investigation. The materials used for the repair of CSF rhinorrhea were surgicel, temporalis fascia, conchal chondroperichrondrium, middle turbinate free mucoperiosteum graft, thigh fat and fascia lata. The follow up period of patients range from 14-44 months. The outcome of endoscopic CSF repair with use of multilayer grafts was evaluated by electronic records regarding recurrence of CSF rhinorrhea post-surgery, hospital admission, revision surgery and digital record of rigid endoscopic findings for the status of graft uptake and CSF leak. Results: In all patients, CSF leak was successfully repaired with use of multilayer grafts in first attempt without any complication. There was female predominance with male to female ratio of 1:6.The mean age of presentation was 43.09years. All 21 patients were presented with spontaneous CSF leak with unknown cause. In 21 patients only one patient presented with bilateral cerebrospinal fluid leak. Cribri form plate was the commonest site of defect in which defect medial to middle turbinate was the commonest followed by ethmoid roof and lateral wall of sphenoid. None of the patients developed meningitis after surgery. None of the patients required lumbar drain. None of the patients presented with cerebrospinal fluid rhinorrhea postoperatively. Conclusions: Endoscopic repair of Cerebrospinal fluid rhinorrhea with the use of multilayer grafts is the safer and effective method with good outcome.

Here, we report detailed studies on magnetic phase transitions and magneto-electric (ME) coupling in $$\text {Fe}_{1-x}\text {Ce}_x\text {VO}_4$$ . X-ray diffraction (XRD) and Raman spectroscopic measurements confirm triclinic crystal structure (P-1) with small variation in lattice parameters and Ce incorporation into the $$\text {FeVO}_4$$ lattice up to 10% of Ce. The presence of local lattice distortions and electronic inductive effect in $$\text {FeVO}_4$$ between $$\text {Fe}^{3+}$$ and $$\text {V}^{5+}$$ ions were found in X-ray absorption near edge structure (XANES) studies due to the presence of $$\text {Fe}^{3+}$$ –O– $$\text {V}^{5+}$$ linkages. Two antiferromagnetic (AFM) transitions similar to $$\text {FeVO}_4$$ appear at 21.86 K and 16.03 K, and Ce doping has little effect on the magnetic transitions. $$^{57}\text {Fe}$$ Mossbauer spectroscopic results show the invariance of Fe valance. Low temperature high magnetic field Mossbauer data depicts the presence of spiral AFM order in all the samples. A sharp peak at 16.0 K in dielectric permittivity with minimal suppression due to applied magnetic field is observed indicating the presence of ferroelectricity and magneto-dielectric coupling. Magnetic and ME transitions are almost robust against Ce doping.

Anomalous behavior of magnetic anisotropy in Co40Fe43B17 film sandwiched between Mo layers has been observed as a function of thermal annealing at different temperatures. The as-deposited amorphous film exhibits a uniaxial magnetic anisotropy, the origin of which can be traced to quenched-in stresses. With thermal annealing up to 300 °C, anisotropy remains unchanged. We observe an anomalous magnetic reversal near the hard axis (HA) in the samples annealed at 350 °C and above. The anomaly of the occurrence of nonuniform magnetization near HA can be explained in terms of distribution of easy magnetization direction, as evidenced by the ripple domain structure in Kerr microscopy images.

SrCoO2.5 (SCO) bulk is found to be a charge-transfer insulator with a positive value of charge-transfer energy (Δ) and 3d6 ground state, which achieves the antiferromagnetic nature through conventi...

We report the structural, ferroelectric, piezoelectric, and dielectric properties of BaTi1−xHfxO3(x = 0, 0.04, 0.08) abbreviated as BT, BHT 1, and BHT-2 lead-free ceramics prepared by solid-state reaction. X-ray diffraction and Raman analysis confirm the formation of tetragonal lattice symmetry with a P4mm space group for studied compositions at room temperature. The tetragonality i.e. c/a ratio and average grain size found to be decreased with Hf4+ incorporation into BaTiO3 (BT). The nonlinearities in dielectric, ferroelectric and piezoelectric properties were observed with Hf4+ incorporation into BT, with the diffuse phase transition (DPT) for BaTi0.96Hf0.04O3 (BHT-1) ceramic, showing improved bulk density ~ 5.90 g/cm3, lattice strain ~ 0.168%, Pr ~ 9.03 μC/cm2, Ec ~ 3.44 kV/cm, Pmax ~ 17.42 μC/cm2, em ~ 7391, Jmax ~ 4.52 × 10–3 A/cm2, d33 ~ 212 pC/N, diffuseness parameter γ ~ 1.58, with relatively higher Curie temperature (TC ~ 125 °C) than pure BaTiO3 a promising candidate for lead-free ferroelectric memory storage (Fe-RAM) and piezoelectric transducers application.

In this work, we investigated the effect of Ag doping (2–20 at.%) on the phase formation of iron mononitride (FeN) thin films. Together with deposition of FeN using reactive dc magnetron sputtering, Ag was also co-sputtered at various doping levels between 2–20 at.%. We found that doping of Ag around 5 at.% is optimum to not only improve the thermal stability of FeN but also to reduce intrinsic defects that are invariably present in (even in epitaxial) FeN. Conversion electron Mössbauer spectroscopy and N K-edge x-ray near edge absorption measurements clearly reveal a reduction of defects in Ag doped FeN samples. Moreover, Fe self-diffusion measurements carried out using secondary ion mass spectroscopy depth-profiling and polarized neutron reflectivity in 57Fe enriched samples exhibit an appreciable reduction in Fe self-diffusion in Ag doped FeN samples. Ag being immiscible with Fe and non-reactive with N, occupies grain-boundary positions as nanoparticles and prohibits the fast Fe self-diffusion in FeN.

Introduction: Filariasis has been known from antiquity. Elephantiasis-painful, disfiguring swelling of the legs and genital organs-is a classic sign of late-stage disease. The genus is named after Wucherer, a Brazilian physician who reported microfilariae in chylous urine in 1868. Lymphatic filariasis is a devastating disease and it is found in more than 80 countries across the world [1,2]. Approximately 1 billion people across the world are at risk. It affects countries like south and Central America, West and East Africa, East Mediterranean, Southeast Asia, and Western Pacific. W bancrofti accounts for 90% of all filariasis cases in the world [3]. National Filaria Control Programme launched in 1955 has operational, training and research components [4]. The main strategies of which were the vector control, detection and treatment of filarial cases and delimitation of endemic areas. This program continues to be in place, in addition to the program to eliminate LF in India. Measurement of microfilaremia is a well-recognized gold standard for demonstrating the impact of interventions but is not an optimal method of monitoring or surveillance because of requirement of nocturnal blood collection and relatively less insensitive test for infection [5]. Materials and Methods: This study was carried out in Govt General Hospital & Filaria Clinic, Guntur District of Andhra Pradesh, and Ethical Permission for the study was obtained 90 samples were collected from those attending the Government General Hospital with signs and symptoms of filariae they were designated as Group I [Test]. 10 normal serum samples Group II [Normal Controls] and 10 serum samples Group III [Endemic Normal] from normal individuals in the endemic pockets identified by filarial control program officers which were detected smear negative were collected as controls Results: The results of ELISA were compared with the microfilariae detection by slide method, it was found that the only 2 cases each in the male and female, a total of 4 cases were detected by the slide methods rest all the cases were detected as negative. With ELISA method it was found that the total numbers of positive cases were 53 and total numbers of negative cases were 37 in the test group I. The comparison of the same results with the normal control samples revealed that all the cases were reported as negative by slide method however by ELISA 7 out of total 10 cases were detected with the antigens and antibodies to microfilariae. Discussion: We in the present study tried to compare the results obtained by conventional slide method of detection of filarial versus the ELISA method; we found that ELISA was far superior in detecting the filariae antigen, antibodies where the conventional slide methods failed to identify the microfilariae Conclusion: ELISA is superior & cost effective in detection of all cases of microfilariae. Since conventional methods may not able to reliably identify microfilariae in all samples, it is recommended that ELISA be used to detect the presence of microfilariae, particularly in Endemic areas.

Structural evolution with thermal annealing of the thin film of amorphous Co23Fe60B17 depositors on Si/SiO2 substrate has been studied using grazing incidence x-ray diffraction, soft x-ray absorption spectroscopy (SXAS), and secondary ion mass spectrometry (SIMS). Amorphous to crystalline transformation starts occurring in the film at a temperature between 200 and 300 °C, which is significantly below the crystallization temperature of amorphous ribbon of similar composition. In the process, the body centered cubic CoFe is the primary phase to precipitate out. Combined SIMS and SXAS measurements show that at the surface iron gets preferentially oxidized as compared to cobalt. Surface oxidation is found to decreases with thermal annealing in vacuum. Boron is found to gradually migrate to the surface and get sublimated. Higher surface and interface energies and depletion of B with thermal annealing are expected to be the cause of lower thermal stability of the film. Magneto-optical Kerr effect measurements show that the as-deposited film possesses a well-defined uniaxial magnetic anisotropy. The anisotropy does not disappear even after the partial crystallization of the film. This suggests that the origin of the observed anisotropy is a combined effect of long-range internal stresses and possible chemical short range order in the film.

The Co 100 − x Ni x ( x = 20 , 40 & 60 ) surface alloys were deposited on Si (100) substrate by dc-magnetron sputtering technique and were investigated using Grazing Incidence X-ray Diffraction (GIXRD), X-ray reflectivity (XRR), Energy dispersive X-ray analysis (EDAX) and Magneto-Optical Kerr Effect (MOKE) measurements. GIXRD measurements suggested a compositional induced structural transition from hcp to fcc structure at x = 40. MOKE measurements indicate that the prepared alloys are soft ferromagnet with the coercive field in the range of few mT. The MOKE microscopy domain image suggests that magnetization reversal occurring through domain wall motion and coherent rotation. The angle-dependent coercivity (Hc) is numerically fitted with a two-phase model of magnetization reversal. Large anisotropy dispersion is observed for hcp Co–Ni alloys compared to fcc Co–Ni alloys. The hcp Co80Ni20 alloy has highest value of coercivity at 0° but for fcc Co60Ni40 and Co40Ni60 alloys, the coercivity became highest at 120°. The magnetization reversal along hard axis occurs through coherent rotation for fcc Co60Ni40 and Co40Ni60 alloys whereas in hcp Co80Ni20 alloy magnetization reversal is governed by formation of fine domains.

The study has made on Ni-doped BiFeO3 (BFO) thin films principally its magnetic properties. BiFe1−xNixO3 (Ni = 0.025, 0.05, 0.075 and 0.10) films were synthesized by the indigenously developed novel hot-wall spray pyrolysis system. It is evidenced from field-emission scanning electron microscopy (FESEM) that Ni doping tremendously modified the shape of the particles from individual rod structure to grouped nanocrystalline grains. M–H curve reveals that Ni doping lead to increase in saturation magnetization and remanent magnetization values of BFO at room temperature (RT) and low temperature (LT). These changes are unveiled due to the structural disorder evidenced from Grazing Incidence X-ray Diffraction (GIXRD) and oxygen vacancy evidenced from X-ray photoelectron spectroscopy (XPS), which are responsible for the magnetic exchange interactions between Fe–O–Fe and Fe–O–Ni. The study of coercivity and blocking temperature with M–H and M–T curves showed that incorporation of Ni decreases the anisotropic energy and coercivity values. These results confirmed that Ni doping modifies the canting structure order which breaks the domains into multi-domains. High retentivity with optimum coercivity makes Ni doped BFO as a good soft magnetic material which finds applications in magnetic data storage devices.

The magnetic state and the spin-phonon coupling in the Eu0.75Y0.25MnO3 are investigated using temperature dependent magnetization, Raman spectroscopy and Mossbauer spectroscopy measurements. The magnetization data showed bifurcation in zero-field cooled and field-cooled warming curves and indicate two antiferromagnetic transitions at 47 K and 22 K. Short range ferromagnetic correlations are clearly observed well above the antiferromagnetic transition temperatures, which are attributed to the presence of Griffiths-like phase. The temperature dependent Raman spectroscopy measurements showed anomalous softening of phonon modes well above the antiferromagnetic ordering temperature of ∼47 K and also showed signatures of both the ordering temperatures. The Mossbauer spectra showed anomalous changes in hyperfine field as a function of temperature which match with the temperature at which B2g phonons showed softening.

Herein, we present defect-induced photoluminescence behavior of Ga-doped ZnO (GZO) thin films with varying doping (Ga) concentrations and energetic ion irradiation. The Ga-doped ZnO thin films were prepared by a sol-gel spin-coating method. Micro-photoluminescence (μ-PL) was carried out to investigate the defect-related emission with the variation of doping concentration and ion irradiation. The PL spectra revealed that all films showed near-band-edge (NBE) emission along with a broad visible emission band, consisting of violet, blue, green, and yellow emission bands. The intensity of these emission bands was found to be strongly dependent on the Ga doping concentration and ion irradiation. Interestingly, a pronounced violet emission band around 2.99 eV (415 nm) was observed for the Ga-doped ZnO thin films with high Ga doping concentration, whereas an irradiated film with high ion fluence exhibited a strong green emission around 2.39 eV (519 nm); however, we concluded that the violet emission might have originated from zinc interstitial defects (Zni), and the concentration of Zni increased with the increasing doping concentration. The green emission is ascribed to the oxygen vacancies (VO), and the concentration of the VO defects increases with the increasing ion fluence. Thus, the μ-PL spectra of the irradiated films with emission dominating in the blue and green regions could be attributed to the formation of extended defects such as clusters and ionizing centers of Zni and VO. Herein, an in-depth understanding of the variation in defects related to the emission bands from these films is reported and correlated with the transport properties of these films for their possible optoelectronic applications.

Mineral chemistry of the ilmenites, drawn from the red sediments along the Bhimunipatnam coast, Andhra Pradesh, India was determined by EPMA technique. The major constituents are TiO2 and FeO, and the value of Ti/(Ti + Fe) < 0.5 of these ilmenites indicate that they are relatively fresh ‘ferrian ilmenites’ and were contributed recently to the red sediments in the study area. Using the mineral chemical data, the end-member composition of the analyzed ilmenites was calculated, which reveals that they are of ‘ilmenite - hematite’ and ‘ilmenite - geikielite - hematite’ composition, derived from calc-alkaline magma-sourced charnockites and metapelitic khondalite suite of rocks respectively of the Eastern Ghats granulite belt. The TiO2 content and Mn/Mg ratio of the study ilmenites indicate that these rocks constitute their provenance in the Gosthani river basin. Their back scattered electron (BSE) and scanning electron (SEM) images show their prominent sub-angular to sub-rounded shape, corroborating the study under microscope, with some preserving signatures of exsolution intergrowth, earlier deformation and rounded shape, all of which are attributed to their transportation by the Gosthani river, after their liberation from their provenance rocks.

$\mathrm{NdGa}{\mathrm{O}}_{3}$ (NGO) is an important substrate material often used in depositing functional oxide thin films. We have carried out temperature-dependent polarized Raman and infrared spectroscopy studies along with theoretical calculations on single-crystal NGO, which revealed a structural phase transition from centrosymmetric space group Pbnm to noncentrosymmetric space group $Pbn{2}_{1}$ at \ensuremath{\sim}200 K. The microscopic origin of the phase transition is extracted using a unique protocol involving polarized Raman spectroscopy (PRS) studies carried out as a function of crystallographic orientation. Here, we demonstrate the power of PRS in probing directional atomic rearrangements across the phase transition.