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Context: External inflammatory root resorption has rapid onset and progresses aggressively. It leads to cementum loss, which allows communication between the infected pulp and the periodontium through the denuded dentinal tubules. Primary management strategy includes adequate chemomechanical debridement and lesion arrest for which maintaining alkaline pH and aerobic conditions is essential for healing and repair of the resorption defect. Aims: The aim of this study is to evaluate rise in pH and oxygen release at the site of simulated external root resorption cavities using different oxygen-releasing biomaterials. Materials and Methods: In 40 extracted single-rooted teeth access opening and chemomechanical debridement were done. Cavities simulating resorption defect are prepared on the roots. The samples are divided into four groups (n = 10) based on the biomaterial used. After placing the biomaterial, the root apices were sealed. Half of the samples from each group were tested for oxygen release using dissolved oxygen meter and the other half for rise in pH using pH meter at 7, 14, 21, and 28 days. Statistical Analysis: The pH values were analyzed using Friedman 2-way analysis of variance (ANOVA) and Kruskal-Wallis test. Oxygen release was measured using the two-way and repeated-measures ANOVA. Results: Calcium peroxide group showed the highest mean pH and oxygen release than other groups at any given point of time. Conclusions: Incorporating oxygen-releasing biomaterials such as calcium peroxide and perfluorodecalin into intracanal medicaments, such as calcium hydroxide, creates an alkaline and oxygen-enriched milieu in the periapical tissues.

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The analog resistive switching properties of amorphous InGaZnOx (a-IGZO)-based devices with Al as the top and bottom electrodes and an Al-Ox interface layer inserted on the bottom electrode are presented here. The influence of the electrode deposition rate on the surface roughness was established and proposed as the cause of the observed unusual anomalous switching effects. The DC electrical characterization of the optimized Al/a-IGZO/AlOx/Al devices revealed an analog resistive switching with a satisfactory value for retention levels, but the endurance was found to decrease after 200 cycles. The predominant conduction mechanism in these devices was found to be thermionic emission. An in-depth analysis was performed to explore the relaxation kinetics of the device and it was found that the current has a lower decay rate. The current level stability was tested and found reliable even after 5 h. The cost-effective and precious metal-free nature of the a-IGZO memristor investigated in this study makes it a highly desirable candidate for neuromorphic computing applications.

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INTRODUCTION: Pediatric dizziness is an uncommon complaint presenting to the Otolaryngology clinic. While the term dizziness may be used to describe any altered sensation of orientation to the environment which includes presyncope, light-headedness and ataxia, vertigo refers to a false sensation of motion of self or surroundings. Although a variety of etiologies are known to cause dizziness and vertigo, evaluation of this symptom becomes challenging in children who are unable to clearly explain what they experience, the provoking factors, associated symptoms and the duration of attacks. Vestibular tests are also difficult to conduct in the pediatric age group leading to apathy from the clinician. OBJECTIVES: To ascertain the prevalence of pediatric vertigo in children under 18 years of age, presenting to the Otolaryngology Clinic of a tertiary care hospital, and to describe the clinical profile, investigations and diagnosis in these children. METHODS: A prospective cross-sectional, descriptive clinical study was undertaken from January 1, 2018 to April 30, 2019. All children below the age of 18 years presenting to our department with primary complaints of dizziness were included in the study. After a thorough history and physical examination, screening methods and diagnostic tests were conducted to make a diagnosis. Referrals were sought from other specialties when necessary. RESULTS: The number of children visiting the Department for various ENT ailments during the study period was 10,950. Among these 89 children presented with a primary complaint of dizziness. Their ages ranged from 3 to 18 years; mean age was 11.42 years (SD 3.45). A diagnosis was made in all except two children. The most common cause of dizziness in the age group less than 6 years was benign paroxysmal vertigo of childhood (BPVC) and in the older children was migraine associated vertigo, which was also the commonest overall diagnosis made (28.1%). This was followed by circulation related dizziness like orthostatic hypotension and vasovagal syncope (15.7%). CONCLUSIONS: The prevalence of pediatric dizziness in children presenting to the Otolaryngology clinic was 0.8%. The diagnosis of pediatric vertigo may be challenging, but careful history and examination along with guided investigations and referrals results in correct diagnosis in almost all patients.

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We explored the electronic and magnetic properties of the lanthanide double perovskite Dy2FeCoO6 by combining magnetization, Raman and Mössbauer spectroscopy and neutron diffraction along with density functional theory (DFT) calculations. Our magnetization measurements revealed two magnetic phase transitions in Dy2FeCoO6. First, a paramagnetic to antiferromagnetic transition at T N = 248 K and subsequently, a spin reorientation transition at T SR = 86 K. In addition, a field-induced magnetic phase transition with a critical field of H c ≈ 20 kOe is seen at 2 K. Neutron diffraction data suggested cation-disordered orthorhombic structure for Dy2FeCoO6 in Pnma space group which is supported by Raman scattering results. The magnetic structures ascertained through representational analysis indicate that at T N, a paramagnetic state is transformed to Γ5(Cx, Fy, Az) antiferromagnetic structure while, at T SR, Fe/Co moments undergo a spin reorientation to Γ3(Gx, Ay, Fz). The refined magnetic moment of (Fe/Co) is 1.47(4) µ B at 7 K. The antiferromagnetic structure found experimentally is supported through the DFT calculations which predict an insulating electronic state in Dy2FeCoO6.

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To compare the results of myringoplasty by using operating microscope (postaural) with that of myringoplasty by using endoscope (permeatal). Our study was conducted in Department of ENT of in Chirayu Medical College and Hospital. Total 60 patients of age group 18-60 were taken for study having chronic otitis media or trauma with central perforation. Patients were randomly selected microscopic or endoscopic myringoplasty. 30 patients for Microscopic Myringoplasty and 30 patients for endoscopic Myringoplasty were selected. Out of total 60 patients 35 were females and the 25 were males, 27 were in the age group 15-30 and 23 were in age group 31-45 and only 10 in the age group of 46-60. 18-30 age group cohort was predominant. The average time taken for endoscopic myringoplasty was 65.5 ± 3.45 min and for microscopic myringoplasty 85.7 ± 3.42 min. 26 were having Large central perforation (LCP), of which 13 underwent microscopic and 13 underwent endoscopic myringoplasty. The graft was taken up in situ in 22 patients while 4 patients had small residual central perforation. Out of these four residual perforations 3 were done by endoscopy and 1 by microscopy. 19 (of 60) were having Medium size central perforation (MCP), 10 were operated with endoscope and 9 with microscope. 15 (60) were having Small central perforation (SCP), 7 done with endoscope and 8 with microscope. In all patient graft take up was well. Large central perforation present in maximum patient and had least graft uptake as compared to MCP and SCP. Out of the 30 these endoscopic myringoplasty 27 patients had good graft uptake and 3 had small central residual perforation after 3 months. Out of the 30 microscopic myringoplasty 29 patients had good graft uptake and 1 patient had small central residual perforation after 3 months. In our study pre operative and post operative Air Bone Gaps (ABGs) were 22.05 ± 2.04 and 9.05 ± 1.36 db respectively in endoscopic myringoplasty and 21.81 ± 1.85 and 8.55 ± 1.44 db respectively in microscopic myringoplasty. Microscopic myringoplasty has greater success rate in larger perforations that is LCP and MCP and equal result in SCP. Advantage of microscope is depth perception and both hands are free for procedure which is limitation of endoscopic myringoplasty (need to use endoscope holder). Advantage of endoscopic permeatal myringoplasty is superior visualization, least tissue trauma and better cosmetic outcome, almost equal graft uptake and hearing outcome with less operative time. Endoscope system is portable, so convenient for surgeon where microscope is not available. Also endoscope is a less costly armamentarium. Our study shows better result in myringoplasty can be achieved if both methods of surgery are used in combination.

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The aim of this study is to assess the incidence of post traumatic BPPV and evaluate its treatment outcomes in mild and moderate traumatic head injury patients. The study population consisted of 128 patients (89 male:39 female) who were admitted with head and neck injury (Motor Vehicle Accident, Blow to the head, Fall from Height, Whiplash injury) as inpatients in Department of Neurosurgery in Tertiary care hospital in Kerala during a 2 month period from 1st April 2014 to 31st May 2014. The age range was 10-70 years and mean 39.8 with standard deviation 15.5. All cases were evaluated and serially followed up to a period of 6 months in Department of Otorhinolaryngology. In our study, the number of patients with mild injuries (Glasgow coma scale 13-15) were 108 and moderate injury (Glasgow coma scale 9-12) were 20. We found out that post traumatic BPPV was found to be 17% of the traumatic brain injury patients. All patients were treated with particle re-positioning maneuvers and were followed up for a period of 6 months. Recurrence were reported in 9 (40.9%) patients. In these patients re positioning maneuvers were repeated.

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We report the experimental observation of spin reorientation in the double perovskite Ho2FeCoO6. The magnetic phase transitions in this compound are characterized and studied through magnetization and specific heat, and the magnetic structures are elucidated through neutron powder diffraction. Two magnetic phase transitions are observed in this compound-one at [Formula: see text] K, from paramagnetic to antiferromagnetic, and the other at [Formula: see text] K, from a phase with mixed magnetic structures to a single phase through a spin reorientation process. The magnetic structure in the temperature range 200-45 K is a mixed phase of the irreducible representations [Formula: see text] and [Formula: see text], both of which are antiferromagnetic. The phase with mixed magnetic structures that exists in Ho2FeCoO6 gives rise to a large thermal hysteresis in magnetization that extends from 200 K down to the spin reorientation temperature. At T N2, the magnetic structure transforms to [Formula: see text]. Though long-range magnetic order is established in the transition metal lattice, it is seen that only short-range magnetic order prevails in the Ho3+ lattice. Our results should motivate further detailed studies on single crystals in order to explore the spin reorientation process, spin switching and the possibility of anisotropic magnetic interactions giving rise to electric polarization in Ho2FeCoO6.

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Unusual features in magnetization resembling the kinetic arrest of a magnetic glass state are observed in the La-doped double perovskite, SrLaFeCoO6. Neutron powder diffraction experiments confirm the presence of antisite disorder as well as a lack of long-range magnetic order down to 4 K in this double perovskite which displays spin glass-like features in dc and ac susceptibilities. Magnetic relaxation observed through cooling and heating under unequal fields (CHUF) point towards unusual domain dynamics which is supported by a broad memory effect. Among the two anomalies that are observed at [Formula: see text] 75 K and at [Formula: see text] 250 K in the magnetic measurements, the former is associated with a spin-freezing temperature below which the magnetic glass state is experimentally verified. The magnetometric experiments detailed in the paper bring out the non-equilibrium metastable magnetic states in this disordered magnetic system. The magnetic glass state described above manifests in the electrical resistivity [Formula: see text] through the formation of a 'hard gap' because of the spin-exchange energy following the formation of magnetic glass. It is observed that the combination of disorder and magnetic glass state leads to a large, negative magnetoresistance (MR) of ≈47[Formula: see text] at 5 K in 8 T.