33 research outputs found

    Fabrication of chitosan based nanofibers by electrospinning and their characterisation

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    Electrospinning is used to produce fibers in the nanometer range by stretching a polymeric jet using electric field of high magnitude. Electrospinning leads to the formation of continuous fibers ranging from 0.01 to 10 ìm . The ultra-fine fibers produced by electro spinning are expected to have two main properties, a very high surface to volume ratio, and a relatively defect free structure at the molecular level . The development of nanofibers by electrospinning process has led to potential applications in filtration, military protective clothing, and biological applications such as tissue engineering scaffolds, drug delivery devices , artificial organ components etc. The present study is an attempt to fabricate composite nanofibers that can be used as tissue engineering scaffolds. The approach involves the blending of two different polymers both being biocompatible and biodegradable but one is natural and other is synthetic along with a surfactant. Composites in the form of nanofibers were formed via electrospinning technique. Different ratios of Chitosan:PEO(Polyethylene glycol:DATB(Dodecyltrimethylammonium bromide) blends were prepared and successfully electrospunned so that the nanofibers obtained could mimic the natural ECM(Extra Cellular Matrix). It was found that usage of DTAB in the blend yielded fibers in the range of 50-250 nm which could be suitable for tissue engineering.. The prepared composite scaffolds were characterised using several techniques such as SEM(Scanning Electron Microscopy), FTIR(Fourier Transform Infrared Spectroscopy, XRD(X-ray Diffraction) . Also solubility and biodegradability tests were carried out for the prepared scaffolds. It was found that at feed rate 0.5ml/hr and voltage 25kV ,Chitosan:PEO ratios of 70/30 and 80/20 with DTAB concentration of 15mM yielded better nanofibers as compared to higher DTAB concentrations

    Ceria as an Efficient Nanocatalyst for Organic Transformations

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    Valuable chemicals, fuels and pharmaceuticals obtained by the transformation of raw materials have fascinated a lot of researchers in past few decades. However, to reduce problems related to these transformations different green, sustainable and economic techniques have been developed to carry out such organic transformations. Development of nanostructured catalysts has been preferred to accomplish heterogeneous catalytic organic transformations because of greater number of surface-active sites for catalytic processes, high catalyst recovery rate, environment friendly nature and their ease of synthesis. Besides the advances in nanocatalysis, certain challenges including not well-defined morphologies due to loss of control over it and loss of catalytic activity during operation need to be addressed. Ceria is actively investigated in field of catalysis. As a ubiquitous component in catalytic system, its inception is like an irreplaceable component in organic transformations. In this chapter, we appropriately reported various fabricating approaches to synthesize Cerium and CeO2-rooted nanoparticles and cerium nanoparticles supported on various support materials, accompanied with multimetallic schemes that show notable contribution to the field of catalysis. This comprehensive chapter will provide an improved understanding of nanostructured CeO2 and will provide deeper insight in the catalysis of Ce-based nanostructured materials and further widen their ambit of applications

    Indian Bengal Delta : climate change, awareness and responsibilities

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    The Bi-Monthly Newsletter “Equalnews” focuses on Environment and Systems of Inquiry. The topic is “Indian Bengal Delta: climate change, awareness and responsibilities” (page 8-12). The Government of India has announced the National Climate Change Action Plan (2008) with eight National Missions, later to become twelve missions by 2014. The world’s largest mangrove forests called “Sundarbans” (named after a species of mangrove Sundari /Hereteria) are part of the delta of Ganga-Brahmaputra-Meghna (GBM) basin, known also as the Indian Bengal Delta (IBD). The article reviews background and concerns of the IBD region, calling for good governance and co-ordinated action

    Role of thalassemia screening in prevention and control of thalassemia - a 5 year experience

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    Background: Thalassemia is a commonest genetic blood disorder in India which can be prevented by antenatal screening and prenatal diagnosis. Aim of the study was to screen antenatal women and their spouses to detect “couples at risk” of thalassemia major births and offering them genetic counseling and option of prenatal diagnosis thereby preventing the birth of thalassemia major babies.Methods: Thalassemia screening for antenatal women was done by NESTROFT test and RBC Indices (MCV, MCH, and RBC count). Confirmation of diagnosis was done by HPLC test. Husbands of women testing positive on HPLC were also tested and couples at risk detected. They were counseled and referred for prenatal genetic diagnosis. Women carrying thalassemia major fetus were advised termination and those with normal and thalassemia minor fetus were advised to continue pregnancy.Results: A total of 93871 patients were screened and HPLC was done on 10983 patients. 7.07% had one or the other hemoglobinopathies and 5.8% had beta thalassemia trait. Among antenatal beta thalassemia trait was found in 5.02%, HbD in 0.36%, HbE in 0.58% and HbS 0.05%. Forty two “at risk couples” (both husband and wife thalassemia trait) were identified, 16 of these underwent prenatal diagnosis and 3 thalassemia major births were terminated.Conclusions: Lack of awareness, late registration, husbands not coming/turning up for their test and “at risk couples” opting out of prenatal diagnosis are the cause of thalassemia major births which can be prevented if awareness is generated amongst masses, screening and prenatal genetic diagnosis services are made widely available

    A Review on Most Opthalmic Viral Disease Conjunctivitivs (Eye Flu)

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    Ophthalmology clinics around the world see a lot of patients with conjunctivitis. Severe pain, impaired vision, and a painful pupillary reaction are all red flags for more serious intraocular disorders that should be taken into account while treating suspected cases of conjunctivitis. In patients with unusual findings and a chronic course, it is also important to have a complete medical and ocular history and do a comprehensive physical examination. The existence of a systemic ailment affecting the conjunctiva may be shown by concurrent findings on physical exam and pertinent history. The vast majority of cases of conjunctivitis still originate from viruses. Bacterial conjunctivitis is the second most prevalent cause of infectious conjunctivitis; however it is much less common than viral conjunctivitis. Nearly half of the population experiences allergic conjunctivitis, characterised by symptoms like itching, mucoid discharge, chemosis, and edoema of the eyelids. A patient with conjunctival irritation and discharge who has used preservative-containing eye drops regularly likely has toxic conjunctivitis. Timely diagnosis, proper classification of the various aetiologies, and suitable treatment are essential components of effective management of conjunctivitis

    Structural phase transitions in perovskite BaCeO3 with data mining and first-principles theoretical calculations

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    Several experiments conducted over decades have revealed that the perovskite-structured BaCeO3 goes through a series of temperature-induced structural phase transitions. However, it has been frequently observed that the number of phases and the sequence in which they appear as a function of temperature differ between experiments. Insofar as neutron diffraction and Raman spectroscopy experiments are concern, four structures are well characterized with three transitions: Pnma to Imma [563 K] to R-3c [673 K] to Pm-3m [1173 K]. In contrast, thermoanalytical methods showed multiple singularities corresponding to at-least three more structural transitions at around 830 K, 900 K, and 1030 K. In account of these conflicting experimental findings, we computed free energy phase diagram for BaCeO3 employing crystal structure data mining in conjunction with first principles electronic structure and phonon lattice dynamics. A total of 34 polymorphs have been predicted, the most stable of which follows the Glazer classification of the perovskite tilt system. It has been predicted that the Cmcm and P4/mbm phases surpass Pnma at 666 K and 1210 K, respectively. At any temperature, two alternate tetragonal phases (P42/nmc and I4/mcm) are also found to be 20 to 30 meV less favored than the Pnma. While the calculated stability order of the predicted polymorphs is in acceptable agreement with the results of neutron diffraction, the transitions observed in thermoanalytical studies could be ascribed to the development of four novel phases (Cmcm, P4/mbm, P42/nmc, and I4/mcm) at intermediate temperatures. However, we analyze that the R-3c phase predominantly stabilized over a broad temperature field, masking all subsequent phases up until the cubic Pm-3m. Consequently, the novel phases predicted to occur in thermoanalytical studies are only fleetingly metastable.Comment: 20 pages, 5 figures, 1 tabl

    Polyphenols, Flavonoids, Mineral Elements, and Biological Activities of Ginger and Cinnamon Essential Oil and Extracts as Regulated by Their Isolation Procedures

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    Our research compared the chemical make-up of wild Ginger and cinnamon, including their essential oils (EOs), total phenol, and total flavonoid, for their antioxidant and antibacterial effects in vitro. The mineral (nutritional and poisonous) components of the plant were also identified in this investigation. Hydro distillation (HD), steam distillation (SD), and microwave-assisted distillation (MAD) were used to extract the EOs, and gas chromatography with flame ionization detection (GC-FID) and mass spectrometry detection (GC-MS) were used to examine them. 2,2-diphenyl-1-picrylhydrazyl (DPPH) was used to evaluate the EOs' antioxidant properties. The essential oil was analyzed, and twenty-six components were found to make up 97.73% of the oil with a yield of 0.202%. The primary components were pulegone (74.81%), menthone (13.01%) and piperitone (3.82%). Neutron activation analysis (INAA) and inductively coupled plasma optical emission spectrometry (ICP-OES) were used to detect twenty-one elements, including macro- and micro-elements (Ba, Br, Ca, Cl, Co, Cr, Cs, Eu, Fe, K, Mg, Mn, Mo, Na, Rb, Sb, Sc, Sr, Th, U, and Zn), with the mineral element concentration being very close to the FAO recommendation

    A Review on Geographical and Pharmacological Distribution of Brassica Oleracea

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    Background: White cabbage, scientifically known as Brassica oleracea var. capitata f. alba, is a cruciferous vegetable that has long been valued for its culinary and medicinal uses. For the treatment of numerous illnesses, such as diabetes, cancer, inflammation, hypertension, hypercholesterolemia, bacteria, oxidation, and obesity, various preparations derived from various portions of the plant, including roots, shoots, leaves, and the entire plant, are utilized. Objective: Botany, distribution, traditional applications, phytochemistry, and pharmacological properties of B. oleracea var. capitata are all going to be assessed in this review. In addition, the gaps in knowledge will be filled and new research opportunities in pharmacology will be highlighted by this review. Method: Through an internet search of internationally recognised scientific databases, a variety of resources were gathered to gain a comprehensive understanding of Brassica oleracea var. capitata. These resources included research papers, reviews, books, and reports.   Results: Alkaloids, flavonoids, organic acids, glucosinolates, steroids, hydrocarbons, and about forty-nine other phytochemical components of Brassica oleracea var. capitata have been culled from various sources. Bactericidal, antioxidant, anti-inflammatory, antibacterial, anti-obesity, anticoagulant, hepatoprotective, and anticancer are only a few of the pharmacological activities exhibited by crude extracts and phytoconstituents of Brassica oleracea var. capitata. Here you may find a complete inventory of the phytochemical components and pharmacological information pertaining to Brassica oleracea var. capitata. Conclusion: Results showed that Brassica oleracea var. capitata is a significant medicinal plant with multiple pharmacological effects, and the study also looked at its phytochemistry, traditional applications, and pharmacological activity. Our goal in conducting this assessment of this plant was to bridge knowledge gaps in the field and lay the groundwork for future studies and medication development. While researching Brassica oleracea var. capitata, we did find a number of significant traditional applications and pharmacological properties

    DMAP-catalysed synthesis, antibacterial activity evaluation, cytotoxicity and docking studies of some heterocyclic molecules bearing sulfonamide moiety

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    DMAP has been shown to be a highly efficient nucleophilic catalyst when compared to triethylamine and pyridine using acetonitrile as solvent for the synthesis of a series of novel N- heterocyclic sulfonamide derivatives. The influence of the reaction parameters, like choice of solvent, catalyst, amount of catalyst and reaction time on product yield has been studied. Antibacterial screening involving a range of sulfonamide analogues as new peptide deformylase (PDF) inhibitors have been focused. The molecules show significant antibacterial activity (MIC value 6.2 − 3.1 µg/mL) against B. subtilis, S. pyrogenes, P. vulgaris and P. mirabilis. Potential in silico docking studies have been in conjugation with in vitro antibacterial results. Molecular docking of all compounds with PDF enzyme (PDB code: 1G2A) explain how certain moieties play significant roles in increasing the binding interactions and stabilizing the protein-ligand complexes. The compounds also have confirmed low extent of cytotoxicity when tested on HEL and HeLa cell lines
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