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A 43-year-old male presented with painless loss of vision in the left eye (LE) of 5 days duration. The patient had been hospitalised for cerebral malaria and kidney infection. Streptococcus pneumoniae growth had been obtained from blood and urine cultures, and the patient had been diagnosed with endogenous endophthalmitis elsewhere. Best-corrected visual acuity (BCVA) in LE was 20/60, N12. Fundus examination showed a yellowish-white lesion in the macular area in LE. Optical coherence tomography revealed sub-internal limiting haemorrhage in LE. The patient was observed. Two weeks following presentation BCVA in LE improved to 20/32, N6 with almost complete resolution of lesion.

Purpose: To report a case of posttraumatic retinal pigment epithelium (RPE) tear complicated with exudative retinal detachment that underwent spontaneous resolution. Methods: Case report. Results: A 61-year-old healthy female presented with sudden-onset loss of vision in the left eye for 5 days following blunt trauma. She had undergone left upper eyelid and eyebrow laceration repair elsewhere. A comprehensive ophthalmic examination revealed a subfoveal RPE tear with exudative retinal detachment in the left eye. There was spontaneous healing of RPE tear and complete resolution of exudative retinal detachment 2 weeks following the initial presentation. Conclusions: RPE tear is an extremely rare complication following blunt trauma. The size of the RPE tear can play an important role in determining the final visual prognosis in such cases.

Purpose: This study aimed to document the spectrum of ocular manifestations of hematological malignancies presenting to a tertiary health center in Eastern India and their association with blood parameters. Methods: This hospital-based cross-sectional study was conducted from August 2021 to July 2022. Patients diagnosed with leukemia, lymphoma, and multiple myeloma were enrolled in the study. A comprehensive ophthalmic evaluation was done in each case. Results: A total of 97 patients with a confirmed diagnosis of hematological malignancies and meeting the inclusion and exclusion criteria were included in the study. Ocular manifestations were noted in 48 (49.48%) patients. Acute lymphocytic leukemia accounted for 35.4% of cases, followed by acute myeloid leukemia (31.25%), lymphoma (4.2%), and minimum manifestation in multiple myeloma (2.1%) patients. Among 48 patients with ocular manifestations, anterior segment involvement was found in 6.2% of cases, with subconjunctival hemorrhage being the most common, and the posterior segment was involved in 100% of patients, with intraretinal hemorrhages being the most common manifestation. A statistically significant association was noted between hemoglobin, total red blood cell count, and total platelet count with posterior segment manifestations (p < 0.001). On multivariable logistic regression, only total leucocyte count and total platelet count were significant predictors for ocular manifestation. Conclusion: Indirect involvement of the retina is the most common ocular pathology in hematological malignancies, with intraretinal hemorrhages being the most common finding. Ophthalmic examination is highly recommended as a part of the routine evaluation at the time of diagnosis of hematological malignancies and periodically thereafter to diagnose any ocular involvement.

A 10-year-old healthy male child presented with pain, redness, and swelling in the left eye of 10 days duration. There was a positive history of trauma. Clinical examination revealed a subconjunctival nodular lesion in the left eye. Surgical exploration under general anesthesia revealed a scleral abscess with an intraocular foreign body lodged in it. Aspergillus terreus growth was obtained on culture. The patient was aggressively treated with anti-fungal medications. Complete resolution was obtained one month following the presentation.

Cultural heritage images are among the primary media for communicating and preserving the cultural values of a society. The images represent concrete and abstract content and symbolise the social, economic, political, and cultural values of the society. However, an enormous amount of such values embedded in the images is left unexploited partly due to the absence of methodological and technical solutions to capture, represent, and exploit the latent information. With the emergence of new technologies and availability of cultural heritage images in digital formats, the methodology followed to semantically enrich and utilise such resources become a vital factor in supporting users need. This paper presents a methodology proposed to unearth the cultural information communicated via cultural digital images by applying Artificial Intelligence (AI) technologies (such as Computer Vision (CV) and semantic web technologies). To this end, the paper presents a methodology that enables efficient analysis and enrichment of a large collection of cultural images covering all the major phases and tasks. The proposed method is applied and tested using a case study on cultural image collections from the Europeana platform. The paper further presents the analysis of the case study, the challenges, the lessons learned, and promising future research areas on the topic.

The most alumina-rich compound in the CaO-Al2O3 system is calcium hexaaluminate (CaAl12O19, CA6). CA6 ceramics were synthesized by the sol-gel auto combustion method. CA6 phase formation has been achieved at 1200°C, which is a much lower temperature than the convention process (>1600°C). The influence of Sr2+ substitution on the densification of Ca1-xSrxAl12O19 (x = 0, 0.1, 0.2, and 0.3) ceramics was investigated. The X-ray diffraction analysis and structural refinement indicated the substitution of Sr2+ ions into the lattice of CA6. The elongation of the “c” direction of the CA6 crystal structure was found with Sr2+ ion substitution. Surface morphology analysis showed a crystal growth with Sr2+ substitution in CA6 upto x = 0.2 composition. The 1600°C sintered specimen (with x = 0.2 composition) showed the bulk density and open porosity of 3.39 g/cm3 and 4.92%, respectively. Thus, auto combustion synthesis and Sr2+ substitution into CA6 ceramics are feasible and beneficial for the densification of the ceramics.

Use of sophisticated adsorbent materials to clean harmful dye-contaminated water is rapidly gaining popularity. Among different adsorbent, magnetic ferrites based adsorbent are gaining much attention because of their easy recyclability. In this current work, activated charcoal (AC) modified magnetic BaFe12O19 (BaM) ferrite-based novel adsorbent (BaM-AC) powder was synthesised through a sol-gel combustion route. As a model dye pollutant, methyl blue (MB) was used to estimate the adsorption efficiency of BaM-AC adsorbent. X-ray diffraction (XRD) was utilised to analyse pure BaM and BaM-AC powder phases. Fourier transform infrared spectroscopy (FTIR), Brunauer, Emmett and Teller (BET), vibrating sample magnetometer (VSM) and field emission scanning electron microscope (FESEM) were also used for the characterisation of prepared adsorbents. The surface area of BaM-AC powder determined by BET was 5.93 m2 g−1. The BaM-AC adsorbent has a saturation magnetisation (Ms) of 56.8 emu g−1 and a coercive field (Hc) of 5176 Oe. Microstructural analysis showed the porous morphology of the material. In-depth studies with BaM-AC powder investigated how pH, adsorbent dose, adsorption period, MB dye concentration, and effect of temperature affected MB dye adsorption. Conferring to the outcomes of the MB-adsorption experiment, the equilibrium was reached after around 45 minutes. Pseudo-second-order kinetics and the Sips isotherm model govern the adsorption process. BaM-AC powder exhibited a good recyclability up to five-regeneration cycle. These outcomes suggest that the composite material has the potential to serve as an effective adsorbent for dye-containing wastewater treatment. [ABSTRACT FROM AUTHOR]

BaFe12O19 (BaM) hexaferrite was synthesised through the coprecipitation method. BaFe12O19-activated charcoal-chitosan (BaM-AC-CS) composite was synthesised through ultra-sonication assisted water in the oil microemulsion method. Morphology of BaM hexaferrite, activated charcoal, and BaM-AC-CS composite powder was evaluated using FESEM. The average particle size of the composite powder was 60 µm. BaM-AC-CS composite powder exhibited a surface area of 41.5 m2 g −1 and pore volume of 0.041 cm3 g−1. The magnetic behaviour of BaM and BaM-AC-CS composite was analysed using a vibrating sample magnetometer. Pure BaM ferrite showed saturation magnetisation (Ms) of 69.3 emu g −1 and coercivity of 2670 Oe. BaM-AC-CS composite powder showed a Ms value of 26.8 emu g −1 which was sufficient for efficient magnetic separation of it in water suspension. The point of zero charge (pHpzc) of composite powder was 6.7. The composite powder was used for the adsorption of methyl blue (MB) dye solution of pH of 6 at 303, 313 and 323 K respectively. The dye removal capacity increased with increase in temperature. The adsorption process followed pseudo-second-order kinetic model and satisfied Redlich-Peterson as well as Sips adsorption isotherm. The composite powder showed a maximum Sips adsorption ability of 254.6 mg g −1 at 323 K temperature. The free energy and enthalpy changes confirmed the spontaneous and endothermic nature of the adsorption. The composite powder also showed good adsorption capacity in five consecutive regeneration cycles. All these results suggest that the BaM-AC-CS powder will be a viable material for MB dye adsorption in wastewater treatment. [ABSTRACT FROM AUTHOR]

Due to their highly malleable electromagnetic characteristics, W-type hexaferrite BaZn2Fe16O27 (Zn2W) shows significant promise as an emerging magnetic material for high-frequency applications. In this study, Mg2+ substituted Zn2W type hexaferrite; BaZn2−xMgxFe16O27 (x = 0.0, 0.5, 1.0, 1.5, 2.0) was synthesized via the co-precipitation route. The X-ray diffraction (XRD) analysis showed the formation of pure W-type phase at 1300 °C/4 h sintering. The bulk densities of compositions were between 4.4 and 4.8 g cc−1. FESEM microstructure showed a dense morphology for all the composition except x = 0.5. The highest saturation magnetization (Ms = 70.5 emu g−1) was observed for x = 1.0 composition. The permittivity (ε), permeability (µ), miniaturization factor (n) and characteristic impedance (Zi) values at 500 MHz were in the range 19.08–50.16, 9.59–11.93, 13.79–23.45 and 0.47–0.74 respectively. Ansys HFSS simulation results showed good antenna characteristics for x = 1.5 composition. Hence, it may be concluded that Mg2+ substituted Zn2W can be useful for ultra-high frequency antenna substrate applications. [ABSTRACT FROM AUTHOR]

This work aims to provide a detailed account of structural, morphological, magnetic, and dielectric characteristics of Ba2Zn2Fe12O22 (Zn2Y) and CoFe2O4 (CoF) ferrites composite. The composites; (Zn2Y)1-x(CoF)x (x = 0.0, 0.2, 0.4, 0.6, 0.8, and 1.0) were prepared by coprecipitation method. All compositions were sintered at 1200 °C for 4 h. X-ray diffraction (XRD) analysis showed the occurrence of two distinct ferrite phases in all composites. The composition with x = 0.2 showed maximum bulk density among all composites. The microstructure of different composites, evaluated by FESEM analysis, was almost similar, where plate like hexaferrite and cubic spinel ferrite phases were present. The saturation magnetization (Ms), coercivity (Hc) and remanence magnetization (Mr) of the composite were increased with the increase in CoF ferrite content. Among all composite, the composition with x = 0.2 showed maximum permeability (µ ~ 18) and permittivity (ε ~ 34) at 100 MHz because of its high bulk density. All composites showed a stable permeability upto 300 MHz. Dielectric and magnetic losses were low up to about 500 MHz. The composition with x = 0.80 showed an equivalent µ and ε, good miniaturization factor (n ~ 14) and characteristic impedance (Zi ~ 1). The magneto-dielectric characteristics of composites imply that they can be used in high-frequency microwave antenna applications. [ABSTRACT FROM AUTHOR]

BaFe12O19 (BaM) hexagonal ferrite was synthesised through the co-precipitation route. The thermal decomposition behaviour of co-precipitated powder was studied by DSC-TG. XRD and Raman analysis confirmed the formation of pure BaM phase at 900°C calcination temperature. Morphological analysis was done using FESEM. The magnetic behaviour of BaM was analysed using a vibrating sample magnetometer. The saturation magnetisation (Ms) of 67.7 emu g−1 and coercivity of 5106 Oe was observed in BaM. BaM ferrite with a surface area of 8.2 m2 g−1 was used for the adsorption of methyl blue (MB) and sunlight-induced photodegradation. The optical band gap of the ferrite was ~2.9 eV. The adsorption process followed the pseudo-second-order model and satisfied Langmuir adsorption isotherm. BaM particles showed the maximum Langmuir saturation adsorption ability of 223.86 mg g−1 at an initial MB solution pH of 5.7. The free energy and enthalpy changes of the adsorption confirmed the spontaneous and exothermic nature of the process. About 73% of degradation of MB was found within 3 h of sunlight-induced photocatalytic degradation. Reproduced BaM powder showed high adsorption and degradation efficiency even after five cycles. All these results suggest that BaM particles can be used as a promising material for the adsorption and degradation of MB in wastewater treatment. [ABSTRACT FROM AUTHOR]

BaFe12O19 (BaM) was synthesized through the co-precipitation route. Pure phase BaM was formed after calcination of precipitated powder at 900 °C. BaM was sintered at three different temperatures; 1100, 1200, and 1300 °C to study the sintering kinetics by varying the sintering time from 1 to 4 h. Apparent porosity decreased, and bulk density increased with increasing sintering temperature and period. A bulk density of about 4.6 g/cm3 was achieved after sintering at 1300 °C/4 h. The rate-controlling mechanism of BaM densification was the diffusion of oxygen, and the activation energy for the sintering process was 274 kJ/mol. The grain size of BaM increased with rising sintering temperatures. Permittivity increased from about 11 to 17 and the permeability increased from about 10 to 16 with the increase in sintering temperature from 1100 to 1300 °C. Saturation magnetization was also enhanced to about 69 emu/g after sintering at 1300 °C/4 h. Therefore, BaM ferrite synthesized through the co-precipitation route can be effectively used for high-frequency applications after sintering at 1300 °C. [ABSTRACT FROM AUTHOR]

The most alumina-rich compound in the CaO-Al2O3 system is calcium hexaaluminate (CaAl12O19, CA6). CA6 ceramics were synthesized by the sol-gel auto combustion method. CA6 phase formation has been achieved at 1200°C, which is a much lower temperature than the convention process (>1600°C). The influence of Sr2+ substitution on the densification of Ca1-xSrxAl12O19 (x = 0, 0.1, 0.2, and 0.3) ceramics was investigated. The X-ray diffraction analysis and structural refinement indicated the substitution of Sr2+ ions into the lattice of CA6. The elongation of the "c" direction of the CA6 crystal structure was found with Sr2+ ion substitution. Surface morphology analysis showed a crystal growth with Sr2+ substitution in CA6 upto x = 0.2 composition. The 1600°C sintered specimen (with x = 0.2 composition) showed the bulk density and open porosity of 3.39 g/cm3 and 4.92%, respectively. Thus, auto combustion synthesis and Sr2+ substitution into CA6 ceramics are feasible and beneficial for the densification of the ceramics. [ABSTRACT FROM AUTHOR]