Influences of copolymers (Copovidone,Eudragit RL PO and Kollicoat MAE 30 DP) on stability and bioactivity of spray-dried and freeze-dried lysozyme

Protein stability is the most crucial factor in protein pharmaceutical preparations. Various techniques were applied for producing stable protein formulations such as spray-drying and freeze-drying. However, heating and freezing stresses are disadvantages for proteins using these methods, respectively. Accordingly, excipients have been used to preserve therapeutic effects of proteins during processing and for long period of time. Therefore, influences of Copovidone, Eudragit^® RL-PO and Kollicoat^® MAE-30 DP (as excipients) on stability and integrity of lysozyme (as a model protein) in spray-dried and freeze-dried forms were investigated. Protein formulations in both dried forms were prepared without and with the addition of mentioned excipients at different concentrations. Protein formulations were characterized for yield determination, morphology using scanning electron microscopic (SEM), thermal analysis by Differential Scanning Calorimetry (DSC), secondary structure stability using Fourier transform infrared (FT-IR) spectroscopy and biological activity. All protein formulations were subjected to a stability study as solid protein formulations for 3 weeks at 24?°C/76% relative humidity and aqueous protein samples were stored at 50?°C for 30?min in a water bath. Results showed that Copovidone successfully preserved integrity and biological activity of lysozyme before and after storage in both spray-dried and freeze-dried forms with more advantage for using higher concentration of the same excipient. Smooth spheres of spray-dried lysozyme formulations with Copovidone were smaller than spray-dried lysozyme without and with Kollicoat^® MAE-30 DP, which affected %yield produced. Copovidone has demonstrated valuable protection ability for lysozyme.     

Structural,mechanical, and electrical properties of carbon nanoparticles synthesized from diesel

We studied the elemental analysis, structural morphology, mechanical, and electrical properties of carbon nanoparticles synthesized from diesel. The spherical carbon particle size in the range of about 10 to 80 nm in diameter was observed in scanning electron microscope (SEM) studies that were identified by Atomic force microscopy (AFM) study as an aggregation of carbon particles of average size 2.5 nm. The surface rms of carbon nanoparticle thin film (CNTF) was measured directly by AFM and found 0.22 nm. The Derjaguin–Muller–Toporov (DMT) elastic modulus of carbon nanoparticles (CNPs) was measured by PeakForce QNM mode of AFM. The minimum and maximum elastic modulus was measured of 0.40 GPa and 43.89 GPa, respectively. The resistivity, conductivity, magneto resistance, mobility, and average Hall co-efficient were measured by “Ecopia Hall-effect measurement system” by four-point Van der Pauw approach at ambient condition. We demonstrated I–V characteristic at the Indium/CNTF thin film interface, which is accompanied by rectifying behavior.     

Biosynthetic Gene Cluster of Cetoniacytone A,an Unusual Aminocyclitol from the Endosymbiotic Bacterium Actinomyces sp. Lu 9419

A gene cluster responsible for the biosynthesis of the antitumor agent cetoniacytone A was identified in Actinomyces sp. strain Lu 9419, an endosymbiotic bacterium isolated from the intestines of the rose chafer beetle (Cetonia aurata). The nucleotide sequence analysis of the 46 kb DNA region revealed the presence of 31 complete ORFs, including genes predicted to encode a 2‐epi‐5‐epi‐valiolone synthase (CetA), a glyoxalase/bleomycin resistance protein (CetB), an acyltransferase (CetD), an FAD‐dependent dehydrogenase (CetF2), two oxidoreductases (CetF1 and CetG), two aminotransferases (CetH and CetM), and a pyranose oxidase (CetL). CetA has previously been demonstrated to catalyze the cyclization of sedoheptulose 7‐phosphate to the cyclic intermediate, 2‐epi‐5‐epi‐valiolone. In this report, the glyoxalase/bleomycin resistance protein homolog CetB was identified as a 2‐epi‐5‐epi‐valiolone epimerase (EVE), a new member of the vicinal oxygen chelate (VOC) superfamily. The 24 kDa recombinant histidine‐tagged CetB was found to form a homodimer; each monomer contains two βαβββ scaffolds that form a metal binding site with two histidine and two glutamic acid residues. A BLAST search using the newly isolated cet biosynthetic genes revealed an analogous suite of genes in the genome of Frankia alni ACN14a, suggesting that this plant symbiotic nitrogen‐fixing bacterium is capable of producing a secondary metabolite related to the cetoniacytones.     

Economic assessment of carbon capture by minichannel absorbers

In this work, a physio‐economic model supported by lab‐scale experiments assessing the economic viability of minichannel based carbon capture units is presented. The net present value of (capital and operating) costs (NPVC) ensued throughout the plant life is selected as the benchmarking parameter. An optimization problem is formulated and solved with the objective of minimizing the NPVC of the unit subject to constraints imposed by the physics of absorption and pressure drop limits; both of which are captured via experimentally deduced empirical correlations. The results show that the minichannel absorbers are economically competitive to conventional systems for low capacity CO₂ capture achieving savings ranging from ～50% to 3% for plant capacities ranging from 5 to 50 MMSCFD, respectively, primarily due to their lower capital costs. At higher plant capacities, the higher operating costs of the minichannel units dominate their NPVC and as such lead them to lose their competitiveness. © 2017 American Institute of Chemical Engineers AIChE J, 64: 620–631, 2018     

Effect of Location of Restraint on Fire Response of Steel Beams

Restrained steel beams, when exposed to fire, develop significant restraint forces and often behave as beam-columns. The response of such restrained steel beams under fire depends on many factors including: fire scenario, beam slenderness ratio, location of axial restraint at the supports, and high-temperature properties of steel. A set of numerical studies, using finite element computer program ANSYS, is carried out to study the fire response of steel beam-columns under realistic fire and restraint scenarios. Results from the parametric studies indicate that fire scenario, beam slenderness, location of axial restraint and high-temperature creep have significant influence on the behavior of restrained beams under fire conditions. Severe fires produce high axial forces at early stages of fire exposure; whereas in moderate fires, significant axial force develops only at later stages of fire exposure. Axial restraint enhances the fire resistance due to the development of tensile catenary action in restrained beams. Furthermore, restrained beams with low slenderness ratio exhibit better fire performance when the axial restraint at the support is located at the bottom flange.     

Slope instability analysis in Phyllitic rock in the Lesser Himalayan using three different modeling approach

Bulletin of Engineering Geology and the Environment - The numerical methods for slope stability problems always have a serious concern related to their continuum and discontinuum nature. In...     

EMI Shielding Characteristics of Electrically Conductive Polymer Blends of PS/PANI in Microwave and IR Region

Conductive polymeric blends (CPBs) of polystyrene and polyaniline (PS/PANI) were prepared by solution casting method in various compositions. Film thickness of CPBs was achieved?～?250 micron. PS/PANI blend films were analyzed for electromagnetic interference (EMI) shielding characteristics in microwave and near-infrared (NIR) regions. PS/PANI blends showed remarkable features. Most mobile telecommunications use GHz frequency range and shielding effectiveness was observed in 9 GHz to 18 GHz. In 9 GHz to 18 GHz frequency range, 45 dB shielding effectiveness was measured. CPBs were also analyzed in the NIR region and showed transmittance of <1%. Microwaves and NIR radiation are the most abundant in the environment and cause damage to human health. Both types of radiation causes serious damage to electronic devices as well.

     

A novel efficient image encryption algorithm based on affine transformation combine with linear fractional transformation

Multidimensional Systems and Signal Processing - Algebraic structures and their hardware–software implementation gain considerable attention in the field of information security and coding...