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To exclusively report the clinical category of mechanical secondary acquired lacrimal duct obstruction (SALDO) secondary to the caruncle and plica hypertrophy. Prospective interventional case series involving 10 consecutive eyes with megalocaruncle and plica hypertrophy were enrolled in the study. All patients presented with epiphora secondary to a demonstratable mechanical obstruction of the puncta. All patients underwent high magnification slit-lamp photography and Fourier-domain ocular coherence tomography scans (FD-OCT) of the tear meniscus height (TMH) pre- and post-operatively at 1-month and 3-months. Caruncle and plica size, position, and their relationship to the puncta were noted. All patients underwent partial carunculectomy. Primary outcome measures were demonstrable resolution of the mechanical obstruction of the puncta and the reduction in the tear meniscus height. The secondary outcome measure was the subjective improvement of the epiphora. The mean age of the patients was 67 years (range: 63–72 years). The average TMH was 843.1 (range: 345–2049) microns pre-operatively and 195.1(91–379) microns at 1-month follow-up. All patients reported significant subjective improvement in epiphora at 6-months follow-up. One patient had bilateral granuloma at the surgical site at two weeks and was managed by simple excision and topical tapering steroids. Histopathology revealed hyperplastic epithelium with goblet cells with chronic inflammatory cells in the sub-epithelial region and the stroma. The role of the caruncle in the causation of mechanical SALDO needs to be carefully assessed in patients beyond the sixth decade. Excellent objective and subjective outcomes can be achieved by a partial carunculectomy and plica semilunaris excision. [ABSTRACT FROM AUTHOR]

This study concerns the synthesis and structure related electrical property analysis of CaO doped ZrO2@mullite composites. Two synthesis techniques (solid state reaction route and thermal plasma sintering) are used which results the formation of a composite consisting of mixed phase of orthorhombic mullite, tetragonal and monoclinic zirconia. The lattice parameters, residual strains, average crystallite size and cell volume of these CaO‐doped ZrO2@mullite composites are obtained from XRD analysis. Stabilization of t‐ZrO2 phase at room temperature is confirmed. Porous microstructure observed in SEM images results in low dielectric constant value of these composites. At room temperature and selected frequency of 1MHz, the dielectric constant and loss factor of 4.7 and 3.826 × 10−2 is observed for conventional CaO stabilized ZrO2@mullite composite and that of 3.8 and 2.19 × 10−2 is reported for plasma sintered CaO stabilized ZrO2@mullite composite. The impedance spectroscopic analysis demonstrates the negative temperature coefficient of resistance (NTCR) behavior and non‐Debye type relaxation behavior of both the CaO stabilized ZrO2@mullite composites. A negligible effect of electrode polarization is realized in these composites. The electronic band gap of conventional and plasma sintered CaO stabilized ZrO2@mullite composites is found to be around 3eV. [ABSTRACT FROM AUTHOR]

The addition of 8 mol% of Y2O3 to the ZrO2@mullite composites stabilizes the metastable tetragonal phase of ZrO2 in conventional and plasma‐sintered Y2O3‐stabilized ZrO2@mullite composites. A fused, highly dense, and interconnected microstructure is formed in the case of plasma‐sintered Y2O3 stabilized ZrO2@mullite composite. At 1 MHz frequency, the room temperature εr${\varepsilon }_r$ and tanδ of (10.37 and 2.06) is obtained for the conventional Y2O3 stabilized ZrO2@mullite composite and that of (38.8 and 4.02) is observed for the plasma sintered Y2O3 stabilized ZrO2@mullite composite. The substitution of Y3+ in place of Zr4+ creates sufficiently large oxygen vacancies at the grain boundary regions of these composites endowed mostly with the ZrO2 phase. In conventional Y2O3‐ ZrO2@mullite composites, both dielectric relaxation as well as conductivity relaxation are observed due to the dynamic motion of dipoles and relaxation due to the presence of defect states and porous structures. This leads to higher grain boundary conductivity than the grain conductivity of these composites. Thermally activated conduction mechanisms exhibited in these composite materials are projected from the complex impedance and modulus analysis. The conventional and plasma sintered Y2O3‐ ZrO2@mullite composite has an optical bandgap of 3.26 and 3.58 eV, respectively. [ABSTRACT FROM AUTHOR]

In the current circumstances, when lakhs of people are dying as a result of the COVID‐19 Pandemic, imposing lockdown and shutdown disrupts the socioeconomic conditions of the entire globe to the point that the country's backbone is compromised. A highly modified, effective sterilizing and disinfection system is essential to improve the country or human civilization. To combat the many adverse effects of radiation, not only on human health but also on the environment, ultra violet technology has been introduced. UV technology is also a source of radiation that has health risks; however, changes in wavelength can make the risk low. UVM‐30A sensor module is used in the sanitization to detect UV irradiation in this study effort. An IoT‐based system based on Arduino uno microcontroller, GSM A6 WiFi module, and UVM‐30A is presented to create an automated implanted UV radiation detection device. [ABSTRACT FROM AUTHOR]

The effect of swift heavy ion irradiation on structural, optical, and microstructural properties of TiO2 has been studied. Pellets prepared from TiO2 nanoparticles have been irradiated by 120 MeV Ag ions at different fluences ranging from 5 × 1011 to 1 × 1013 ions cm−2. X‐ray diffraction (XRD), Raman, UV–visible, and photoluminescence (PL) studies indicated anatase phase both in as‐prepared and irradiated pellets. XRD study revealed the crystallite size of the particles as ~16 nm, which is close to the upper limit of the particle size where anatase phase is most stable. Our study thus established the importance of the initial microstructure on the irradiation response of the nanoparticles. Though irradiation did not affect the crystal structure and the polycrystalline nature of the anatase TiO2, it suppressed the crystalline volume fraction. Poisson fitting of the suppression of XRD peak area with irradiation fluence revealed radius of the track of each 120 MeV Ag ion in TiO2 nanoparticles as ~2.1 nm. Irradiation, in addition to creating disorder, darkened the surface of the pellets because of the creation of oxygen vacancies in the TiO6 octahedra. Reorganization of these defects led to suppression of the band gap of TiO2 nanoparticles from 3.19 eV of the pristine sample to 3 eV for samples irradiated beyond a critical fluences 3 × 1012 ions cm−2. The size of the nanoparticles and their agglomeration remained unaffected by irradiation as indicated by field emission scanning electron micrographs. [ABSTRACT FROM AUTHOR]

Nanocomposites of Al and Al2O3 were synthesized by an ultrasonic full cavitation technique which is a novel route for synthesis of uniformly distributed nanoparticles in metal matrix composites. The transmission electron micrograph indicates the uniform arrangement of nanoparticles throughout the metal matrix and the average size of the nanoparticles are in the order of 5 nm. The selected area electron diffraction analysis shows the presence of both Al and Al2O3 phases, which is also evidenced from the X-ray photoelectron spectroscopy analysis. The significant improvement in hardness and Young’s modulus due to the addition of a low weight fraction of nano-sized Al2O3 in aluminium infers that alumina nanoparticulates are distributed uniformly throughout the aluminium metal matrix. Hence, this paper shows a new method for inexpensive fabrication of bulk light weight metal matrix nanocomposites (MMNCs) by the use of noncontact full cavitation method.

Purpose: Our study aimed to evaluate the utility of the anterior segment morphometry for objectively assessing anterior segment architectural changes of corneal clouding in the mucopolysaccharidoses (MPS) cohort and to investigate whether these measurements correlate with the slit-lamp findings on the cornea and early diagnosis of glaucoma.Methods: This retrospective study involved 70 eyes of 35 children with cloudy cornea due to MPS variants. Anterior segment architectural alterations were measured using anterior segment imaging and biometry in MPS children and compared with controls.Results: Mean age of the cohort at the time of assessment was 7.9 ± 4.5 years. Males constituted two-thirds of the cohort. Variants of MPS with cloudy cornea were as follows: Type I (62%), Type IV (11%), and Type VI (22%). Morphometric measurements were available in 22 eyes of 11 MPS children and an age-matched healthy control group. There were significant differences between MPS cohort and controls in refraction in Diopters (5.03 ± 0.39 and 0.01 ± 0.04; P < 0.0001), axial length (AXL) in mm (21.39 ± 0.28 and 23.04 ± 0.28; P = 0.0002), average keratometry in Diopters (40.67 ± 0.44 and 42.83 ± 0.44; P < 0.0001), anterior chamber depth (ACD) in mm (2.92 ± 0.07 and 3.65 ± 0.07; P < 0.0001), and intraocular pressure (IOP) in mmHg (25.2 ± 2.0 and 14.1 ± 2.3; P = 0.0003). Secondary glaucoma was observed in 28% of the MPS cohort.Conclusion: The anterior segment morphometry in the cloudy cornea due to MPS provides an objective measurement of anterior segment architectural changes, thus diagnosing early-onset secondary glaucoma. These findings highlight that cloudy cornea due to MPS variants merits close monitoring throughout life. [ABSTRACT FROM AUTHOR]

The aim of this study was to retrospectively determine clinical features, treatment outcomes, and overall survival in four patients with metastatic retinoblastoma at presentation. The mean age at diagnosis was 63 months (range: 24-108 months). Three patients had overt orbital disease of at least one eye and one patient had microscopic orbital disease with scleral infiltration on histopathology. Metastatic sites included regional lymph nodes (RLN) (n = 4), bone marrow (BM) (n = 2), and cerebrospinal fluid (CSF) (n = 1). The most common sites of RLN were ipsilateral preauricular nodes (two patients) and contralateral parotid gland involvement (one patient). The treatment administered included primary enucleation (n = 1), high-dose intravenous chemotherapy (n = 4), secondary enucleation (n = 2), orbital external beam radiotherapy (n = 3), and intrathecal chemotherapy (n = 1). High-risk features included massive choroidal and microscopic scleral infiltration in the eye that underwent primary enucleation. At a mean follow-up of 33 months (range, 4-68 months), one patient with CSF involvement deceased in 4 months. The remaining three patients were alive and disease-free at the last mean follow-up period of 43 months (range, 18-68 months). The results of our study showed that RLN and BM metastasis respond well to treatment while CSF metastasis is associated with poor prognosis. [ABSTRACT FROM AUTHOR]