Investigating the role of amides on the textural and optical properties of mesoporous-nanostructured theta-Al2O3

Mesoporous-nanostructured theta-Al2O3 was synthesized by an autoclaving technique using different amides i.e., formamide (F), dimethyl formamide (DMF) and diethyl formamide (DEF) at 150 degrees C/24 h followed by calcination at 1000 degrees C. Crystallization and structural behaviour of the as-synthesized materials were characterized by X-ray diffraction and Fourier transform infrared spectroscopy. The porosity study was carried out by N-2 adsorption-desorption (BET) technique. Microstructural features were measured by transmission electron microscopy (TEM). The amide-based solvents played a deliberate role in microstructural and textural features of theta-Al2O3. The DMF-based solvent showed an enhanced surface area of 158 m(2) g(-1). The as-prepared theta-Al2O3 rendered a nano-sheet, nano-rod and nano-flake like morphology for F, DMF and DEF derived products, respectively. From the UV-Vis spectroscopic measurement, the estimated band-gap of theta-Al2O3 was found to be 5.16-5.40eV. Photoluminescence investigation further revealed blue emission particularly for excitation at a wavelength of 252 nm. A DMF-derived sample rendered the lowest band gap due to its smaller crystallite size and higher surface area compared to that of F- and DEF-derived samples

Small molecule conjugates with dimetal species for protein inhibition

Methods for targeting a protein by providing an inhibitor covalently linked to a rhodium(II) complex, introducing the inhibitor to the target protein and allowing the inhibitor and protein to interact. The rhodium(II) complex covalently linked to the inhibitor binds the target protein both inorganically and organically and forms stabilizing secondary contacts between the rhodium(II) complex and the protein

Role of carboxylate ion and metal oxidation state on the morphology and magnetic properties of nanostructured metal carboxylates and their decomposition products

Sub-micron rods and spheres of cobalt succinate sesquihydrate and iron succinate trihydrate/pentahydrate respectively have been synthesized by the reverse micellar route. These precursors are an excellent source for the synthesis of metal and metal oxide nanoparticles. Cubes of (edge length ~ 150 nm) Fe3O4 and elongated particles of Fe2O3 (~ diameter of 200 nm) were obtained. The role of oxidation state of the metal ion in controlling the morphology of the nanostructured dicarboxylates has been investigated. Rods with shorter length were obtained when longer chain dicarboxylate was used as ligand. Heating in nitrogen atmosphere also provided pure Co and α-Fe nanoparticles. The Fe nanoparticles show nearly 100% superparamagnetism. Temperature-dependent magnetic studies show a Morin-like transition for Fe2O3 nanoparticles at 223 K and the Verwey transition at 115 K for Fe3O4 nanoparticles. Co3O4 nanoparticles showed antiferromagnetic ordering at 20 K

Developing Dirhodium-Complexes for Protein Inhibition and Modification & Copper-Catalyzed Remote Chlorination of Alkyl-Hydroperoxides

The work describes the development of a new class of protein-inhibitors for protein-protein interactions, based on metallopeptides comprised of a dirhodium metal center. The metal incorporation in the peptide sequence leads to high increase in binding affinity of the inhibitors. The source of this strong affinity is the interaction of histidine on the protein surface with the rhodium center. In addition to this work, rhodium-based small molecule inhibitors for FK-506 binding proteins are investigated. Also, methodology for rhodium-catalyzed modification of proteins containing surface cysteine has been developed where a simple rhodium(II) complex catalyzes cysteine modification with diazo reagents. The reaction is marked by clean cysteine selectivity and mild reaction conditions. The resulting linkage is significantly more stable in human plasma serum, when compared to common maleimide reagents. Apart from this body of work in chemical-biology, the thesis contains the discussion of development of copper-catalyzed remote chlorination of alkyl hydroperoxides. The atom transfer chlorination utilizes simple ammonium chloride salts as the chlorine source and the internal redox process requires no external redox reagents

Emulsion based solvothermal synthesis of CuO grainy rod via the formation of quasi-quadrangular prism shaped Cu-2(OH)(3)Br for recyclable catalyst of 4-nitrophenol reduction

Quasi-quadrangular prism shaped Cu-2(OH)(3)Br particles were synthesized by emulsion based solvothermal process followed by their transformation to hierarchical copper oxide grainy rods by calcination at 450 degrees C/2 h. In this process, we employed cetyltrimethyl ammonium bromide (CTAB) as cationic surfactant as well as bromide source, 1-butanol as co-surfactant, cyclohexane as organic (oil) medium, copper acetate as aquo-based copper precursor and hexamethylenetetramine ((CH2)(6)N-4) as the source of ammonia under hydrolyzing condition. The length/diameter of hierarchical CuO grainy rods was found to be around 2.5-10 mu m/0.5-1.5 mu m comprising of smaller grain (20-30 nm) assembly. The proposed reaction trajectory based on anion-exchange mechanism was proposed for the transformation of Cu-2(OH)(3)(CH3COO) to Cu-2(OH)(3)Br. The product showed excellent catalytic performance for 4-nitrophenol reduction. The apparent rate constant values increased from 0.532 min(-1) to 1.038 min(-1) with catalyst amount increased from 1 to 3 mg. This investigation refers the novel synthesis approach of CuO grainy-rod from quasi-quadrangular prism shaped Cu-2(OH)(3)Br precursor, and its role as catalyst for 4-nitrophenol reduction

Transmissible Spongiform Encephalopathies & Prion Proteins: A Systematic Review

Prion proteins (PrPc) have been implicated as the causative agent of “Transmissible Spongiform Encephalopathies” (TSE). Apart from this devilish role, prions also have a bright facet of their own and their identity holds much more than just being a pathogenic entity. Role of prions as scaffolding proteins for ligand binding and signal transduction has been reported by several researchers. Role of prions in nerve impulse transmission at neuronal junctions, glyapse and gap junctions have been reported. Prion mediated regulation of calcium ion flux and redox status in turn regulates many major cellular functions. In this review we have focussed mainly on the physiological aspects of prion function apart from its pathological role in TSE. Role of prions in mediation of neuropathic pain, neuroinflammatory diseases and chronic headache has been reported by few researchers. In this review we have tried to correlate such effects of prions and also discuss various therapeutic targets for various diseases influenced by prions

Global transcriptome analysis reveals fungal disease responsive core gene regulatory landscape in tea

Abstract Fungal infections are the inevitable limiting factor for productivity of tea. Transcriptome reprogramming recruits multiple regulatory pathways during pathogen infection. A comprehensive meta-analysis was performed utilizing previously reported, well-replicated transcriptomic datasets from seven fungal diseases of tea. The study identified a cumulative set of 18,517 differentially expressed genes (DEGs) in tea, implicated in several functional clusters, including the MAPK signaling pathway, transcriptional regulation, and the biosynthesis of phenylpropanoids. Gene set enrichment analyses under each pathogen stress elucidated that DEGs were involved in ethylene metabolism, secondary metabolism, receptor kinase activity, and various reactive oxygen species detoxification enzyme activities. Expressional fold change of combined datasets highlighting 2258 meta-DEGs shared a common transcriptomic response upon fungal stress in tea. Pervasive duplication events caused biotic stress-responsive core DEGs to appear in multiple copies throughout the tea genome. The co-expression network of meta-DEGs in multiple modules demonstrated the coordination of appropriate pathways, most of which involved cell wall organization. The functional coordination was controlled by a number of hub genes and miRNAs, leading to pathogenic resistance or susceptibility. This first-of-its-kind meta-analysis of host–pathogen interaction generated consensus candidate loci as molecular signatures, which can be associated with future resistance breeding programs in tea

Role of carboxylate ion and metal oxidation state on the morphology and magnetic properties of nanostructured metal carboxylates and their decomposition products

Sub-micron rods and spheres of cobalt succinate sesquihydrate and iron succinate trihydrate/ pentahydrate respectively have been synthesized by the reverse micellar route. These precursors are an excellent source for the synthesis of metal and metal oxide nanoparticles. Cubes of (edge length ~ 150 nm) Fe3O4 and elongated particles of Fe2O3 (~ diameter of 200 nm) were obtained. The role of oxidation state of the metal ion in controlling the morphology of the nanostructured dicarboxylates has been investigated. Rods with shorter length were obtained when longer chain dicarboxylate was used as ligand.Heating in nitrogen atmosphere also provided pure Co and α-Fe nanoparticles. The Fe nanoparticles show nearly 100% superparamagnetism. Temperature-dependent magnetic studies show a Morin-like transition for Fe2O3 nanoparticles at 223 K and the Verwey transition at 115 K for Fe3O4 nanoparticles. Co3O4 nanoparticles showed antiferromagnetic ordering at 20 K