Optical and dielectric properties of divalent copper based double perovskite compound, Gd2CuTiO6.

In this work, we have investigated high temperature dielectric properties and room temperature optical properties on rare earth ion based orthorhombic Gd2CuTiO6(GCTO). Optical properties like reflectance and band gap were determined from ultra-violet visible (UV-Vis) diffuse reflectance spectroscopy technique and photoluminescence (PL) spectrum. The compound exhibited substantial optical absorption and emission in the visible region. Our findings reveal the presence of an intermediate band, as evidenced by the difference between the band gap values obtained from the Tauc plot using the diffuse reflectance spectrum (3.07 eV) and the PL spectrum (2.4 eV). Furthermore, thermogravimetric analysis demonstrated high thermal stability with <0.4% change in mass over a wide temperature range of 30 °C-1200 °C in air environment. Moreover, lead-halide free compound, GCTO is highly thermally stable oxide double perovskite with wide band gap and absorption in the UV-Vis range are highly suitable for optical applications In addition, dielectric properties of the compound have been examined using impedance spectroscopy as a function of frequency ranging from 500 Hz to 1 MHz and temperature between 300 K and 550 K. Compounds with relaxor behaviour at high temperatures and high thermal stability are desired for several applications. Because of the cation disorders present in this compound, GCTO displays dielectric relaxor behaviour indicative of a distribution of relaxation times. Furthermore, the frequency-dependent modulus illustrated a thermally activated conduction mechanism. Cole-Cole plots of electrical modulus suggest prominent grain contribution above 350 K.

Computer Vision System for Mango Fruit Defect Detection Using Deep Convolutional Neural Network.

Machine learning techniques play a significant role in agricultural applications for computerized grading and quality evaluation of fruits. In the agricultural domain, automation improves the quality, productivity, and economic growth of a country. The quality grading of fruits is an essential measure in the export market, especially defect detection of a fruit's surface. This is especially pertinent for mangoes, which are highly popular in India. However, the manual grading of mango is a time-consuming, inconsistent, and subjective process. Therefore, a computer-assisted grading system has been developed for defect detection in mangoes. Recently, machine learning techniques, such as the deep learning method, have been used to achieve efficient classification results in digital image classification. Specifically, the convolution neural network (CNN) is a deep learning technique that is employed for automated defect detection in mangoes. This study proposes a computer-vision system, which employs CNN, for the classification of quality mangoes. After training and testing the system using a publicly available mango database, the experimental results show that the proposed method acquired an accuracy of 98%.

Is Cartilage a Better Option than Temporalis Fascia for Grafting in Type 1 Tympanoplasty?: An Institutional Study.

Chronic suppurative otitis media (CSOM) is one of the important health problems in our country. The present study was conducted to compare Cartilage and Temporalis Fascia as graft material for Type 1 Tympanoplasty for CSOM. The study was conducted to assess hearing outcome as average AB Gap closure respect to age of the patient and size of perforation, to evaluate Graft uptake with both grafting material and with respect to size of perforation and to find the complication rate. Prospective Comparative study was conducted on 60 patients of CSOM divided in two groups and randomly selected for cartilage Typanoplasty and Temporalis Fascia Tympanoplasty. Hearing result are compared pre and post operative. Group 1(cartilage): Average AB Gap closure was 55% for Small CP, 50% for Moderate CP, 40% for Large CP, 38% for Subtotal CP. In Group 2(Temoralis Fascia): Average AB Gap closure was 81% for Small CP, 72% for Moderate CP, 64% for Large CP, 52% for Subtotal CP. In Group 1, 46% and in Group 2, 69% Average closure of AB gap observed at 12 weeks post operatively. The p value for our study was found to be < 0.05, which statistically indicates better hearing outcome with TF graft. Cartilage is an excellent grafting material because of its accessibility, resistance to negative pressure and high graft uptake rate. Temporalis Fascia is easily available with similar thickness to TM. It showed inferior morphological uptake rate compared to cartilage though functional gain was better.

Comparative Evaluation of Sclerostin Levels in Gingival Crevicular Fluid in the Treatment of Chronic Periodontitis Patients Using Diode Laser as an Adjunct to Scaling and Root Planing: A Clinico-biochemical Study.

AIMS: Sclerostin is an inhibitor of bone formation, and laser irradiation enhances osteoblast proliferation. The objective of this study was to assess and compare the gingival crevicular fluid (GCF) sclerostin level and clinical parameters of chronic periodontitis patients following the application of diode laser (810 nm) as an adjunct to scaling and root planing (SRP). SUBJECTS AND METHODS: Fifteen systemically healthy chronic periodontitis patients (age 35-55 years) with probing pocket depth ≥5mm were included in this split-mouth study. SRP and pocket irradiation with diode laser were done in the test group and SRP alone in the control group at baseline. Low-level laser therapy application and saline irrigation were done in both the groups, respectively, in the 2nd and 3rd visits. Two microliters of GCF samples was collected from both the groups at baseline before treatment and on the 90th day for the assessment of sclerostin concentration. RESULTS: This study showed a statistically significant reduction of clinical parameters in the test and control groups at the end of 3 months. Both the groups showed a statistically significant reduction of sclerostin levels in GCF after 3 months, in which the test group (125.80 ± 28.21 to 82.80 ± 9.31) showed a highly significant reduction (P = 0.000). CONCLUSIONS: The adjunctive use of laser had shown a beneficial effect in terms of clinical parameters and osteoblast proliferation by the reduction in the levels of sclerostin in GCF. From the observations of this study, it can be concluded that the therapeutic effectiveness of diode laser as an adjunct to SRP is having a beneficial effect and sclerostin can be used as a potent biomarker.

Exploring the relationship between LST and land cover of Bengaluru by concentric ring approach.

The present study aims at investigating the impact of land cover features in enhancing or mitigating Land Surface Temperature (LST) in a semi-arid tropical metropolitan city of Bengaluru, India. Spatial distribution of LST and land cover types of the area were examined in the circumferential direction, and the contribution of land cover classes on LST was studied over 28 years. Urban growth and LST were modelled using Landsat and MODIS data for the years 1989, 2001, 2005 and 2017 based on the concentric ring approach. The study provides an efficient methodology for modelling and parameterisation of LST and urban growth by fitting an inverse S-curve into urban density (UD) and mean LST data. In addition, multiple linear regression models which could effectively predict the LST distribution based on land cover types were developed for both day and night time. Based on the analysis of remotely sensed data for LST, it is observed that over the years, urban core area has increased circumferentially from 5 to 10 km, and the urban growth has spread towards outskirts beyond 15 km from the city centre. As urban expansion occurs, the area under the study experiences an expansive cooling effect during day time; at night, an expansive heating effect is experienced in accordance with the growth in UD in the suburban area and outskirts. The regression models that were developed have relatively high accuracy with R2 value of more than 0.94 and could explain the relationship between LST and land cover types. The study also revealed that there exists a negative correlation between urban, vegetation, water body and LST during day time while a positive correlation is observed during night. Thus, this study could assist urban planners and policymakers in understanding the scientific basis for urban heating effect and predict LST for the future development for implementing green infrastructure. The proposed methodology could be applied to other urban areas for quantifying the distribution of LST and different land cover types and their interrelationships.

The impact of spatiotemporal patterns of land use land cover and land surface temperature on an urban cool island: a case study of Bengaluru.

In most of the developing countries, man-made developments in the environment have led to the growing demand to contextualize the land use land cover (LULC) changes and land surface temperature (LST) variations. Due to the modification in the surface properties of the cities, a difference in energy balance between the cities and its nonurban surroundings is observed. The aim of this study is to analyze the spatial and temporal patterns of LULC and LST and its interrelationship in Bengaluru urban district, India, during the period from 1989 to 2017 using remote sensing data. Intensity analysis was performed for the interval to analyze the LULC change and identify the driving forces. The impact of LULC change on LST was assessed using hot spot analysis (Getis-Ord Gi* statistics). The results of this study show that (a) dominant LULC change experienced is the increase in urban area (approximately 40%) and the rate of land use change was faster in the time period 1989-2001 than 2001-2017; (b) the major transition witnessed is from barren and agricultural land to urban; (c) over the period of 28 years, LST patterns for different land use classes exhibit an increasing trend with an overall increase of approximately 6 °C and the mean LST of urban area increased by about 8 °C; (d) LST pattern change can be effectively analyzed using hot spot analysis; and (e) as the urban expansion occurs, the cold spots have increased, and it is mainly clustered in the urban area. It confirms the presence of an urban cool island effect in Bengaluru urban district. The findings of this work can be used as a scientific basis for the sustainable development and land use planning of the region in the future.

Modification of low temperature magnetic interactions in Dy1-x Eu x MnO3.

Solid solutions of rare earth ion (Eu3+) substituted DyMnO3, Dy1-x Eu x MnO3 (x = 0.0-1.0) have been synthesized by ceramic method. Powder X-ray diffraction revealed single phase nature of the compounds with orthorhombic structure. Contributions from the atomic vibrations to the observation of Raman bands have been established and assigned to symmetry stretching and anti symmetry stretching, bending and tilting modes. Raman band frequencies of tilting, asymmetric stretching and bending modes were found to decrease with increasing europium concentration showing softening. Transport studies revealed that all the compounds show semiconducting nature. While the end compounds display hopping process for electrical conduction, all the substituted compounds showed activated type of conduction, and activated energy was found to reduce with increase in x. Molar susceptibility of the substituted compounds for x = 0.1, 0.3 and 0.5 revealed an antiferromagnetic transition corresponding to Mn ions. The fitted Curie-Weiss temperatures also suggested the existence of antiferromagnetic interactions in all the materials. The magnetic field dependent magnetization at various temperatures revealed paramagnetic nature down to 8 K below which hysteresis loops are observed. The presence of strong ferromagnetic correlations between Dy and Mn spins through apical oxygen ions results in the large coercive fields. For temperatures above the antiferromagnetic temperature of manganese ions (39 K) M-H curves show almost straight lines implying the absence of ferromagnetic interactions in the compounds. Different magnetic transitions: from high temperature paramagnetic state to intermediate temperature antiferromagnetic state to low temperature ferromagnetic states are observed in the M-H data.

Attenuation of quorum sensing-regulated behaviour by Tinospora cordifolia extract & identification of its active constituents.

BACKGROUND & OBJECTIVES: The pathogenicity of the nosocomial pathogens, Pseudomonas aeruginosa and Acinetobacter baumannii is regulated by their quorum sensing (QS) systems. The objective of the present study was to examine the effect of the cold ethyl acetate extract of Tinospora cordifolia stem on virulence and biofilm development in the wild type and clinical strains of P. aeruginosa and A. baumannii. The study was further aimed to identify the probable active constituents in the plant extract. METHODS: P. aeruginosa virulence factors viz., LasA protease, LasB elastase and pyocyanin production were analyzed spectrophotometrically. Biofilm formation was studied using crystal violet staining-microtitre plate assay. The plant extract was fractionated using silica gel column chromatography and the most active fraction was derivatized using silylation and analyzed by gas chromatography-mass spectrometry (GC-MS). In silico testing of the molecules identified in GC-MS was performed, for binding to the P. aeruginosa LasI and LasR proteins, to predict the QS inhibitory molecules. RESULTS: The plant extract inhibited three major virulence factors in P. aeruginosa; it exhibited enhanced biofilm formation in P. aeruginosa while decreased biofilm development in A. baumannii. The most active fraction obtained from column chromatography, exhibited suppression of virulence as well as biofilm in both the organisms. Docking scores were calculated for all the molecules identified in GC-MS, and high docking scores were obtained for 2,3,4-triacetyloxybutyl acetate, methyl 16-methyl heptadecanoate, 2-(5-ethenyl-5-methyloxolan-2-yl)propan-2-ol, methyl hexadecanoate and 2-methoxy-4-vinyl phenol. INTERPRETATION & CONCLUSIONS: The compounds showing high docking scores could probably be the QS inhibitors. These molecules can be screened further for the development of new anti-infective drugs.

Removal of Cr(VI) from aqueous solution using chitosan-g-poly(butyl acrylate)/silica gel nanocomposite.

The present work deals with the preparation of the novel sorbent, glutaraldehye crosslinked silica gel/chitosan-g-poly(butyl acrylate) (Cs-g-PBA/SG) nanocomposite by sol-gel method for removal of toxic chromium ion. Prepared nanosorbent was then characterized by FTIR, XRD, DLS, SEM, BET isotherm for its formation and suitability. Its sorption capacity and sorption isotherms were brought under batch mode to suit the optimal parameters viz., contact time, pH, adsorbent dose and initial metal ion concentration which influence the sorption. The theoretical modeling such as Langmuir and Freundlich isotherm adsorption were applied to describe isotherm constants. Equilibrium data agreed well with the Langmuir isotherm model (R(2)=0.9763) with maximum adsorption capacity of 55.71 (mg/g). The kinetic studies showed that the adsorption follows the pseudo-second-order kinetics (R(2)=0.9999). From the results, it was concluded that Cs-g-PBA/SG nanocomposite is an excellent biosorbent for Cr removal from wastewater.

Role of alginate in bone tissue engineering.

Bone, a typical inorganic-organic biocomposite, is made of approximately 70 wt% inorganic components, mainly hydroxyapatite (HAp,Ca(10)(PO(4))(6)(OH)(2)), and 30 wt% of organic matrix, mainly collagen I. Human organ failure caused by defects, injuries, or other types of damage is one of the most devastating and costly problems in human health care. Recently, tissue engineering has emerged as a promising approach for bone repair and reconstruction. The ultimate goal of bone tissue engineering is the fabrication of a construct that matches the physical and biological properties of the natural bone tissue. Biopolymers have some distinct advantages such as their biodegradation rates and mechanical properties can be tailored to a certain extent for specific applications. Alginate, a natural polysaccharide, is readily processable for applicable three-dimensional scaffolding materials such as hydrogels, microspheres, microcapsules, sponges, foams, and fibers. Alginate can be easily modified via chemical and physical reactions to obtain derivatives having various structures, properties, functions, and applications. The purpose of this chapter is to review recent research on alginate in bone tissue engineering.

Industrial applications of marine carbohydrates.

Biomaterials have been used increasingly in various fields, such as drug delivery, imaging, and tissue engineering. The main reason justifying the widespread use of biomaterials relies on its valuable and low-cost source of new drugs. Current research goals are focused on identifying more potent and specific compounds with antitumor, immunomodulatory, antihyperlipidemic, anticoagulant, and antiviral activities. The increasing knowledge of structural analysis and chemical modifications enables the use of these marine carbohydrates in a newer way for the human welfare. This chapter focuses on the recent developments related to industrial and biomedical applications using chitin, chitosan, alginate, agar, and carrageenan derivatives and reports the main advances published over the last 10-15 years.

Dietary coconut kernel protein beneficially modulates NFκB and RAGE expression in streptozotocin induced diabetes in rats.

Previous studies showed that arginine rich coconut kernel protein (CKP) maintains glucose homeostasis in experimental diabetic rats. But the mechanism of this effect was not clear. This study investigated the effect of CKP on the expression of liver receptor for advance glycated end products (RAGE), inducible nitric oxide synthase (iNOS) and NFkB. Diabetes was induced by injecting a single dose of streptozotocin (75 mg/kg body weight) intraperitoneally. After inducing diabetes, CKP was administered to rats orally for 45 days. After the experimental period, serum glucose, insulin, liver glycogen, glucose metabolizing enzyme activities and the expression of liver RAGE, iNOS and NFkB was evaluated. The results showed that CKP beneficially modulated the levels of glucose and insulin as well as the metabolizing enzyme activities. Expression of RAGE and NFkB was found to be over expressed in diabetic rats but was found to be down regulated in CKP fed diabetic rats. iNOS expression was down regulated in diabetic rats, which was expressed normally in CKP fed diabetic rats. These results clearly demonstrated that anti diabetic activity of CKP is mediated through NFkB pathway.

Theoretical studies on the quinoidal thiophene based dyes for dye sensitized solar cell and NLO applications.

A series of quinoidal thiophene based dye molecules were designed and their optoelectronic properties were studied for dye sensitized solar cell (DSSC) applications. The efficiency of the designed dye molecules was analyzed using various parameters such as the HOMO-LUMO energy gap, absorption spectra, light harvesting efficiency (LHE), exciton biding energy (Eb) and free energy change for electron injection (ΔG(inject)). The simulated absorption spectra of the quinoidal thiophene molecules show that the electron withdrawing group substituted molecules exhibit dual band characteristics. We found that the cyano-[5'-(4″-amino benzylidene)-5H-thiophen-2'-ylidene] acetic acid based molecules, QT2B, QT4B, QT5 and QT6, are good candidates for DSSC applications. Furthermore, the study on the polarizability and hyperpolarizability of the designed molecules showed that the electron withdrawing group substituted QT2B-X molecules (X = Cl, Br, CF3, CN and NO2) are good candidates for NLO applications.

S-nitrosothiol tethered polymer hexagons: synthesis, characterisation and antibacterial effect.

In this work, we portray a new controlled nitric oxide (NO) delivery platform by grafting S-nitrosothiol derived from cysteine into the polymeric backbone of poly(vinyl methyl ether-co-maleic anhydride). Nitrosothiols (RSNO's) are linked to the polymeric backbone through solvent displacement method. By adjusting solvent polarity, materials of different shapes and sizes varying between µm and nm are prepared. More often our method of preparation resulted in hexagonally shaped polymeric materials. The structure and RSNO conjugation analysis was investigated using scanning electron microscopy (SEM), FT-IR, UV-Vis spectroscopy and thermogravimetric analysis (TGA). Bactericidal efficacy of nitric oxide releasing polymer hexagons, a novel antibacterial agent is demonstrated against Escherichia coli, Staphylococcus aureus and Pseudomonas aeruginosa. Confocal microscopic studies revealed the enhanced bactericidal effect of polymer hexagons via membrane destruction. Results suggest that this biocompatible NO releasing RSNO conjugated polymer hexagons could be potentially useful for antimicrobial applications.

Rat sperm immobilisation effects of a protein from Ricinus communis (Linn.): an in vitro comparative study with nonoxynol-9.

Previous study conducted in our department showed that 50% ethanolic extract of the root of Ricinus communis possess reversible antifertility effect and a 62-kDa protein (Rp) from this extract is responsible for the antifertility effects. In this study, we compared the spermicidal effect of this Rp with nonoxynol-9 (N-9) in vitro. The sperm immobilisation studies showed that 100 µg ml(-1) of Rp was able to immobilise the sperms completely within 30 s. Sperm revival test revealed that the spermicidal effect was irreversible. There was also a significant reduction in sperm viability and hypo-osmotic swelling in Rp and N-9 treated groups in comparison with the control. In Rp and N-9 treated groups, the number of acrosome-reacted cells was found to be high and also caused agglutination of the spermatozoa, indicating the loss of intactness of the plasma membrane, which was further supported by the significant reduction in the activity of membrane bound 5'-nucleotidase, acrosomal acrosin. In short, the protein Rp possesses spermicidal activity in vitro and its effects are similar to that of nonoxynol 9.

Structural and spectral properties of 4-bromo-1-naphthyl chalcones: a quantum chemical study.

The structural and optical properties of 4-bromo-1-naphthyl chalcones (BNC) have been studied by using quantum chemical methods. The density functional theory (DFT) and the singly excited configuration interaction (CIS) methods were employed to optimize the ground and excited state geometries of unsubstituted and substituted BNC with different electron withdrawing and donating groups in both gas and solvent phases. Based on the ground and excited state geometries, the absorption and emission spectra of BNC molecules were calculated using the time-dependent density functional theory (TDDFT) method. The solvent phase calculations were performed using the polarizable continuum model (PCM). The geometrical parameters, vibrational frequencies, and relative stability of cis- and trans-isomers of unsubstituted and substituted BNC molecules have been studied. The results from the TDDFT calculations reveal that the substitution of electron withdrawing and electron donating groups affects the absorption and emission spectra of BNC.

Spermicidal action of a protein isolated from ethanolic root extracts of Achyranthes aspera: an in vitro study.

A previous study conducted in our department, showed that 50% ethanolic extract of the roots of Achyranthes aspera possess spermatotoxic effects. Preliminary studies also revealed that the active principle may be a protein. In this study a 58 kDa Achyranthes protein (Ap) was isolated from Achyranthes aspera using standard protocols and their effects on the rat sperm was studied in vitro in comparison with nonoxynol-9 (N-9). The sperm immobilization studies showed that about 150 µg of Ap was able to immobilize sperms completely within seconds at a lower concentration than N-9 (250 µg). The sperm revival test revealed that the spermicidal effect was irreversible. There was also a significant reduction in sperm viability and hypo-osmotic swelling in the Ap-treated and N-9 treated groups in comparison to the control. In the Ap and N-9 treated groups the number of acrosome reacted cells were found to be high and it also caused agglutination of the sperms indicating the loss of intactness of the plasma membrane which was further supported by the significant reduction in the activity of membrane bound 5' nucleotidase and acrosin enzyme. Hence this study showed that the protein isolated from the roots of Achyranthes aspera possess spermicidal activity in vitro and can act as a spermicide similar to that of nonoxynol 9. Ap also possessed spermicidal activity against human sperms in vitro.

Effects on spermatogenesis in swiss mice of a protein isolated from the roots of Ricinus communis (Linn.) (Euphorbiaceae).

This study was aimed to evaluate the effect on spermatogenesis of a 62 kDa protein (Rp) isolated from 50% ethanolic extract of the root of Ricinus communis in mice. A dose response study in mice revealed that 25mg/kg body weight/day was the most effective dose. Swiss strain mature male mice of 30 days old were divided into two group namely control and Rp treated (25mg/kg body weight/day). The study showed that sperm motility and count were decreased significantly in the treated group as compared to the control. The fertility index of the treated groups was reduced by 100%. The activity of HMG Co A reductase and cholesterol were increased significantly in the treated group. The testicular activities of 3ßHSD, 17ßHSD, glucose 6-phosphate dehydrogenase and malic enzyme and the level of serum testosterone were decreased significantly in the treated group. The expression of 3ßHSD and 17ßHSD were decreased and the expression of StAR increased significantly in the treated group as compared to the control. Proteolytic digestion of the native protein with trypsin and chymotrypsin showed that the proteolytic cleavage did not affect the spermicidal action of Rp. Hence this study can be concluded that Rp impaired spermatogenesis in vivo by suppressing the production of testosterone.

Antiperoxidative and antiinflammatory effect of Sida cordifolia Linn. on quinolinic acid induced neurotoxicity.

Sida cordifolia is a plant belonging to the Malvaceae family used in many ayurvedic preparations. This study aimed at assessing the effects of ethanolic extract of Sida cordifolia root on quinolinic acid (QUIN) induced neurotoxicity and to compare its effect with the standard drug deprenyl in rat brain. Rats were divided into six groups: (1) control group (2) QUIN (55 microg/100 g bwt/day) (3) 50% ethanolic plant extract treated group (50 mg/100 g bwt/day) (4) Deprenyl (100 microg/100 g bwt/day) (5) QUIN (55 microg/100 g bwt/day) + 50% ethanolic plant extract treated group (50 mg/100 g bwt/day) (6) QUIN (55 microg/100 g bwt/day) + Deprenyl (100 microg/100 g bwt/day). At the end of the experimental period a status of lipid peroxidation products, protein peroxidation product, activities of the scavenging enzymes and the activities of the inflammatory markers were analyzed. Results revealed that the lipid peroxidation products decreased and the activities of the scavenging enzymes increased significantly in the brain of the plant extract treated group, deprenyl treated group and also in the coadminstered groups. The activities of markers of inflammatory responses such as cyclooxygenase and lipoxygenase were found to be significantly increased in the QUIN treated rats and this was decreased upon the administration of plant extract and deprenyl. In short, the study revealed that 50% ethanolic extract of Sida cordifolia has got potent antioxidant and antiinflammatory activity and the activity is comparable with the standard drug deprenyl.