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Influence of chromium ions on photonic applicability of Na2O-Bi2O3-B2O3-SiO2 glass system
No full textGlasses, with composition 10Na2O–10Bi2O3–20B2O3–(60-x)SiO2: Cr2O3 (0 x 0.25), synthesized by melt quenching procedure were characterized by XRD and conducted optical absorption, EPR, and FTIR spectroscopic techniques. The optical absorption spectra portrayed a strong absorption peak at about 642 nm owing to 4A T (F) with a couple of envelopes at about 681 and 712 nm due to 4A T and 4A E transitions, respectively. All doped samples showed two EPR signals, each at low and high magnetic fields caused by the chromium ion isolation and interchange interactions of Cr3＋-Cr3＋ ions, respectively. FTIR spectra have revealed the behaviour of various structural units for different concentration of Cr2O3 in the glass matrix. With the assistance of spectroscopic studies, the observed fall in the rigidity of the samples with higher concentrations of Cr2O3 is attributed to presence of high concentrations of octahedrally resided Cr3＋ ions, which gain more suitability for lasing action
Optical applications of transition metal ion doped phosphate Glasses
No full textThe transition metal ion-doped lithium phosphate glasses are prepared with a novel composition by melt quenching method, XRD patterns revealed their characteristic amorphous nature. The structural and physical properties of the prepared glasses are significantly varying with the increased concentration levels of dopant. Optical absorption and transmission spectra of the glass samples are analyzed. The absorption peaks are observed in ultraviolet, visible and infrared regions.The direct and indirect energy band gap values are decreasing while Urbach's energy values are increasing as the concentration levels of dopants are increasing. The obtained energy band gap values are in the range of semiconductor materials. The optical transmission spectra of these transition metal ion-doped glasses reveal their application as bandpass filters with filtering ability in UV or Visible regions at double and triple wavelengths and hence useful as dual band-pass filters. The glasses with <10 full width half maximum(FWHM) values are useful for narrowband lasers
Syntheses of N-Doped Carbon Quantum Dots (NCQDs) from Bioderived Precursors: A Timely Update
No full text: The emergence of carbon quantum dots (CQDs) opens up new opportunities in different branches of science and technology primarily because of their conducive biocompatibility, tunable bandgaps, and unique optoelectronic properties, namely, photoluminescence (PL) and fluorescence. Although CQDs are given precedence in the literature, the large-scale sustainable synthesis and the purification of CQDs as well as the study of their effects on health and environment remain a challenge. Hence, more sustainable approaches are being developed to make this category of materials widely applicable, specifically in the context of replacing toxic metal-based QDs. Among the reported synthetic protocols employed to prepare CQDs while controlling their properties, the incorporation of various dopants, surface functionalities, and defects into CQDs offers great promises. Amongst the possibilities, nitrogen dopants contribute significantly due to their broader precursor scope, natural abundance in sustainable bioderived resources, and relatively straightforward and inexpensive synthetic
protocols, leading to assorted combinations of nitrogen (N)-doped carbon quantum dots (NCQDs). Here, a brief survey is presented on the recent developments of strategies deployed for the preparation of bioderived NCQDs, emphasizing the uniqueness of the synthetic methodology, choice of precursors, and purification strategies. In addition, characterization, properties, and applications of the selected NCQDs are highlighted. The present status and challenges are also
discussed along with the future direction
Antioxidant potential and optimization of production of extracellular polysaccharide by Acinetobacter indicus M6
No full textAbstract Background
Extracellular polysaccharides (ECPs) produced by biofilm-producing marine bacterium have great applications in biotechnology, pharmaceutical, food engineering, bioremediation, and bio-hydrometallurgy industries. The ECP-producing strain was identified as Acinetobacter indicus M6 species by 16S rDNA analysis. The polymer produced by the isolate was quantified and purified and chemically analyzed, and antioxidant activities have been studied. The face-centered central composite design (FCCCD) was used to design the model.
Results
The results have clearly shown that the ECP was found to be endowed with significant antioxidative activities. The ECP showed 59% of hydroxyl radical scavenging activity at a concentration of 500 μg/mL, superoxide radical scavenging activity (72.4%) at a concentration of 300 μg/mL, and DPPH ˙ radical scavenging activity (72.2%) at a concentration of 500 μg/mL, respectively. Further, HPLC and GC-MS results showed that the isolated ECP was a heteropolymer composed of glucose as a major monomer, and mannose and glucosamine were minor monomers. Furthermore, the production of ECP by Acinetobacter indicus M6 was increased through optimization of nutritional variables, namely, glucose, yeast extract, and MgSO 4 by “Response Surface Methodology”. Moreover the production of ECP reached to 2.21 g/L after the optimization of nutritional variables. The designed model is statistically significant and is indicated by the R 2 value of 0.99. The optimized medium improved the production of ECP and is two folds higher in comparison with the basal medium.
Conclusions
Acinetobacter indicus M6 bacterium produces a novel and unique extracellular heteropolysaccharide with highly efficient antioxidant activity. GC-MS analyses elucidated the presence of quite uncommon (1→4)-linked glucose, (1→4)-linked mannose, and (→4)-GlcN-(1→) glycosidic linkages in the backbone. The optimized medium improved the production of ECP and is two folds higher in comparison with the basal medium. The newly optimized medium could be used as a promising alternative for the overproduction of ECP
The Pursuit of Alachlor Herbicide Toxicity on Eisenia fetida and Its Biochemical Responses
No full textReactive oxygen species (ROS) and reactive nitrogen species (RNS) incessantly produced as by-products of meta-
bolism play significant roles in seed physiology. ROS (hydroxyl, superoxide radical and hydrogen peroxide) and RNS (nitric oxide, nitric dioxide, nitrous acid and dinitrogen tetroxide) content changes in all phases of seed life cycle that influence seed germination, dormancy and longevity. Recent studies illustrate that ROS and RNS are performing oxidative and nitrosative signaling to induce seed germination within oxidative window level. Besides, ROS/RNS-mediated post-translational modifications (PTM) like carbonylation, S-nitrosylation and nitration are gaining in-terest in promoting seed germination. Understanding the signalling pathways, cross-talk with plant hormones and their role in promoting seed germination and dormancy alleviation could pave way for hormone engineering that help in crop productivity, particularly under climatic changing conditions. In addition, role of antioxidants and glutathione thiols in protecting from oxidative damage indicate that these compounds can be used for seed viability/ quality markers that aid in monitoring of crop establishment. In this review, sources of ROS and RNS, their cross-talk with plant hormones (prospects for hormone engineering), signalling functions pertaining to seed germination, dormancy and deterioration have been illustrated. In addition, seed quality markers under climatic changing con-
ditions for effective monitoring of crop stand establishment and diagnostics development have been elucidated
P2X7 receptor in multifaceted cellular signalling and its relevance as a potential therapeutic target in different diseases
No full textThe aim of the present study was to investigate the effect of naringenin (4,5,7-trihydroxy flavo-none) on the pharmacokinetics of metoprolol, a substrate of Cytochrome P-450 3A4 (CYP3A4), CYP2C9, and CYP2D6 in rats.
2. Male Wistar rats were treated orally with metoprolol (30 mg/kg) alone and in combination with naringenin (25, 50, and 100 mg/kg) once daily for 15 consecutive days.
3. The plasma concentrations of metoprolol were determined using Reverse Phase-High Performance Liquid Chromatography (RP-HPLC) on the 1st day in single-dose pharmacokinetic
(PK) study (SDS) and on the 15th day in multiple dosing PK studies (MDS).
4. Compared to the metoprolol control group, the Cmax, AUC, and half-life (T1/2) of metoprolol increased in rats pre-treated with naringenin, while there was no significant change in Tmax. There is a significant decrease in clearance and volume of distribution.
5. The present study results revealed that naringenin significantly enhanced the Cmax, AUC, MRT, t1/ 2, and decreased the clearance of metoprolol possibly through the inhibition of CYP enzymes involved in the metabolism of metoprolol
THERMAL BEHAVIOUR KINETIC MODELING OF CAPSICUM ANNUUM WASTE BIOMASS USING AN ISO-CONVERSION METHOD
No full textIn the present study, the pyrolysis behaviour of Capsicum Annuum stem Waste (CAW) was studied applying thermogravimetric analysis to evaluate the intrinsic kinetic parameters to develop a pyrolysis reactor for utilizing CAW. The thermal decomposition of CAW was achieved between 373 – 1173 K under inert conditions at different heating rates of 10, 20, and 30 K min-1. Model-free kinetic methods like Kissinger-Akahira-Sunose (KAS), Ozawa Flynn Wall (OFW) and Coats Redfern methods were applied to work out the kinetic parameters. To identify the utility of CAW and its biochar, physio-chemical characteristics such as proximate and ultimate analysis, scanning electron microscopy, and Fourier Transform Infrared analysis are reported
Effect of Hydroxypropyl Methylcellulose and Microcrystalline Cellulose in Design and Optimization of Nebivolol Hydrochloride Immediate Release Tablets by Response Surface Methodology
Get PDFThe goal of the research is to design and optimize Nebivolol Hydrochloride immediate-release tablet using response surface methodology. Nebivolol Hydrochloride immediate-release tablets used in the treatment of heart attacks, myocardial infarction. Response surface methodology calculations for this optimization study were performed utilizing Minitab 17. Different formulations of immediate-release were prepared by applying 2 factors 3 levels full factorial design using Minitab 17, which gave 9 formulations by using the wet granulation method. Independent variables like the amount of hydroxypropyl methylcellulose (X1), and microcrystalline cellulose (X2) and dependent variables like the per cent drug release at 45 minutes (Y1), disintegration (Y2) were selected for optimization. The prepared batches of Nebivolol Hydrochloride immediate-release tablets were evaluated for the pre-compression and post-compression parameters like weight variation, thickness, hardness, and friability, disintegration, and in-vitro drug release studies. All the Physicochemical parameters were found satisfactory for prepared tablets. The optimized formulation F7 showed disintegrated in 83 sec, percentage dissolution release 97.85 at the end of 45th minute. The results shows that formulated immediate-release tablets of Nebivolol HCl were better to meet patient compliance with respect to effectiveness
Personalized Medicine: A New Normal for Therapeutic Success
Get PDFThe purpose of this article is to provide a framework for understanding the principles of personalized and precision medicine. Since the advent of the human genome project in 1990, the approach to precision and accurate medicine has been changed. This turns the practice from the “one size fits all” paradigm into one that tailors patient identification, diagnosis and treatment. Personalized medicine has been a disputed vision of the future for two decades. A humanized approach to personalized medicine will offer the possibility of leveraging the physiology of processes and its application of personalized, predictive, participatory, precision and preventive P5 medicine. The predictive variables for the progression of a disease should be investigated within communities to determine preventive measures for at risk people and healthcare can be customized and participative. Accurate diagnosis, surveillance and treatment of diseases includes developments in the identification of biomarkers, the subsequent development of reliable signatures that suit complex disease states, as well as medical approaches that can be continually modified and modulated for dosage and medication selection. This review illustrates significant breakthroughs in the advancement of emerging technology and obstacles of personalized and precise medicine. It will create groundbreaking capabilities in the realization of fully individualized patient care
Optimum weighted multimodal medical image fusion using particle swarm optimization
Get PDFMedical image fusion is a technique that maps information from multiple image modalities into a single image. In past, several multimodal fusion approaches were developed by various researchers, even so, adaptive fusion and robustness are challenging tasks in clinical diagnosis. In this paper, we developed an optimum weighted average fusion (OWAF) for multimodal medical image fusion to improve the multimodal mapping performance. In our approach, conventional discrete wavelet transform (DWT) is used for the decomposition of input multiple modalities into various subgroups. The resultant energy bands were weighted using optimum weights, attained using well known particle swarm optimization algorithm (PSO). Our proposed approach was tested over MRI-SPECT, MRI-PET and MRI-CT image fusion and we used 20 sets of MR/SPECT, 20 sets of MR/PET and 18 sets of MR/CT for our method validation. The quantitative evaluation were performed using established fusion performance metrics such as structural similarity index measure (SSIM), root mean square error (RMSE), peak signal to noise ratio (PSNR), entropy, mutual information (MI), and Edge-based similarity metric(Q AB/F ). Robustness of our proposed fusion approach is tested over gaussian and speckle noise in all the input modalities. The computational performance of our OAWF with PSO algorithm is tested in terms of computational time. The OWAF showed superior performance than existing conventional fusion approaches in terms of information mapping, edge quality and structural similarity in MR/PET, MR/SPECT and MR/CT images in both normal and noisy fusion backgrounds