Quaternion Gravi-Electromagnetism

Defining the generalized charge, potential, current and generalized fields as complex quantities where real and imaginary parts represent gravitation and electromagnetism respectively, corresponding field equation, equation of motion and other quantum equations are derived in manifestly covariant manner. It has been shown that the field equations are invariant under Lorentz as well as duality transformations. It has been shown that the quaternionic formulation presented here remains invariant under quaternion transformations.Comment: Key Words: Quaternion, dyons, gravito-dyons, gravi-electromagnetism. PACS No.: 04.90. +e ; 14.80. H

Application of Natural Convection for Photovoltaic Cooling and Photocatalytic Disinfection

Two investigations for improving renewable technologies are engaged. First is the examination of the enhancement of heat transfer at the rear of a hot photovoltaic panel by natural convection using various configurations and the other is analyzing a new photocatalytic collector for water heating and cleaning. A 20 Watt polycrystalline panel is exposed to indoor simulated solar light, under constant ambient temperature and stagnant wind conditions. Three configurations are considered: a partial heat sink, a water cavity and a water channel. The experimentally obtained convective heat transfer coefficients are 4.4 W•m-2•K-1 at the rear of the bare panel, 1.1 W•m-2•K-1 with the heat sink, 26.6 W•m-2•K-1 with the water cavity and 177 W•m-2•K-1 with the water channel. The channel is attached to a cold reservoir and thermosyphoning is forcing flow through it. This is an efficient method for cooling. In the second part of this study, an integrated solar photocatalytic collector is fabricated and tested. Methylene blue dye and photo-activated catalyst were mixed with the testing fluid. The results show that the system was able to disinfect 1.2 ppm of the dye in water by 80% in the presence of 127 mg•L-1 of AEROXIDE® TiO2 P90 with the thermal efficiency of ηth = 0.67 under the laboratory conditions. It was analyzed under stagnant wind conditions and the heat losses were assessed

Embryonic POU5F1 is Required for Expanded Bovine Blastocyst Formation.

POU5F1 is a transcription factor and master regulator of cell pluripotency with indispensable roles in early embryo development and cell lineage specification. The role of embryonic POU5F1 in blastocyst formation and cell lineage specification differs between mammalian species but remains completely unknown in cattle. The CRISPR/Cas9 system was utilized for targeted disruption of the POU5F1 gene by direct injection into zygotes. Disruption of the bovine POU5F1 locus prevented blastocyst formation and was associated with embryonic arrest at the morula stage. POU5F1 knockout morulas developed at a similar rate as control embryos and presented a similar number of blastomeres by day 5 of development. Initiation of SOX2 expression by day 5 of development was not affected by lack of POU5F1. On the other hand, CDX2 expression was aberrant in embryos lacking POU5F1. Notably, the phenotype observed in bovine POU5F1 knockout embryos reveals conserved functions associated with loss of human embryonic POU5F1 that differ from Pou5f1- null mice. The similarity observed in transcriptional regulation of early embryo development between cattle and humans combined with highly efficient gene editing techniques make the bovine a valuable model for human embryo biology with expanded applications in agriculture and assisted reproductive technologies

IMPURITY PROFILING OF FIRST LINE ANTI-TB DRUG-TERIZIDONE USING CHROMATOGRAPHIC AND RELATED TECHNIQUES

Objective: The objective of the present study was to investigate the stability of TRZ against different stressors and to prepare impurity profile for potential impurities and degradation products (DPs) formed under stress degradation of TRZ bulk drug and formulation. Methods: Three analytical methods were developed; the stability-indicating method that was developed using HPLC instrument with 0.01M ammonium acetate buffer (pH 4.0 using glacial acetic acid (GAA)) and acetonitrile in gradient program. The second method was a UPLC/ESI-MS method using 0.1 % Formic acid in Milli Q water (pH= 2.70) and 0.1%Formic acid in Milli Q water: Acetonitrile (10:90) in gradient program for identification of TRZ and DPs while the third, preparative HPLC method was used for isolation of impurities using (A) 0.05% ammonia (NH3) in water and (B) Acetonitrile+20% mobile phase A in gradient sequence. Gradient sequences are described in the main text. Results: The analytical method for stability study was developed and validated using ICH (Q2) R1 guidelines. The result of stability study by stress degradation showed that TRZ was susceptible to degradation in acid (7 DPs), alkaline, neutral (9 DPs) and oxidative conditions (10 DPs); major DPs were identified (where it was possible) and the chemical structure was elucidated by combining the data of ESI/MS, NMR and/or Tandem MS. The Impurity profiling was completed by reporting all the DPs, either major or minor for TRZ bulk drug and formulation. Conclusion: The complete Impurity profiling for TRZ is reported for the first time in literature. The study data would be add-on for formulation storage condition and further development

Investigation of ion induced bending mechanism for nanostructures

Ion induced bending is a promising controlled technique for manipulating nanoscale structures. However, the underlying mechanism of the process is not well understood. In this letter, we report a detailed study of the bending mechanism of Si nanowires (NWs) under Ga+ irradiation. The microstructural changes in the NW due to ion beam irradiation are studied and molecular dynamics simulations are used to explore the ion–NW interaction processes. The simulation results are compared with the microstructural studies of the NW. The investigations inform a generic understanding of the bending process in crystalline materials, which we suggest to be feasible as a versatile manipulation and integration technique in nanotechnology

DEVELOPMENT AND VALIDATION OF STABILITY INDICATING METHOD RP-HPLC METHOD OF ACOTIAMIDE

Objective: The objective of present work was to develop and validate simple, precise, accurate and specific stability indicating method for determination of acotiamide in presence of its degradation products.Methods: An isocratic RP-HPLC method has been developed using C-8 Thermo Hypersil BDS Column (250 x 4.6 mm i.d., 5µparticle size) with the mobile phase composition of acetonitrile: 0.1 % triethylamine in 0.2% formic acid (30: 70) at column oven temperature of 40 °C. The flow rate was 1.0 ml min-1 and effluent was detected at 282 nm. The method was validated in terms of linearity, accuracy, precision, LOD (Limit of Detection), LOQ (Limit of Quantification) and robustness as per ICH guidelines.Results: The method was found to be linear in the range of 10-60µg/ml. Limit of detection and limit of quantification was found to 0.36µg/ml and 1.10 µg/ml.% Recovery was found to be in the range of 99.45%-99.75%and precision less than 2%. The developed method was successfully applied for estimation of Acotiamide in marketed tablet formulation and percentage assay was found to be 100.45%. Acotiamide was subjected to stress degradation under acid, base, neutral hydrolysis, oxidation, dry heat, photolysis conditions. Significant degradation was observed in acid and base degradation.Conclusion: The developed RP-HPLC method was simple, rapid, accurate, precise and stability indicating for the estimation of Acotiamide in bulk and tablet dosage form

DEVELOPMENT OF HPLC AND CHEMOMETRIC ASSISTED SPECTROPHOTOMETRIC METHODS FOR THE SIMULTANEOUS DETERMINATION OF FIVE ACTIVE INGREDIENTS IN COUGH AND COLD TABLETS AND THEIR APPLICATION TO DISSOLUTION STUDY

Objective: Chemometric assisted spectrophotometry, and HPLC methods have been developed for the simultaneous determination of phenylephrine hydrochloride (PEPH), paracetamol (PCM), guaifenesin (GNF), chlorpheniramine maleate (CPM) and bromhexine hydrochloride (BRM).Methods: The chromatographic separation was carried out on a Phenomenex RPC18 column. An isocratic elution was carried out with the mobile phase comprising methanol, acetonitrile and 10 mM phosphate buffer (pH 3) in the ratio of 27.5:22.5:50 respectively at a wavelength of 218 nm. Two chemometric methods i.e. principal component regression (PCR) method and partial least squares (PLS) method were also developed to quantify each drug in the mixture using the information included in the UV absorption spectra of appropriate solutions in the range 210–320 nm with the intervals of 2 nm at 51 wavelengths.Results: The three methods were successfully applied to a tablet formulation and the results were compared statistically by applying ANOVA, which showed no significant difference among the three methods. The methods were applied to the dissolution study of the five components in tablet formulation and the percentage release of all the five components was found to be greater than 85% within 45 min by all the three methods.Conclusion: Thus, the proposed methods, i.e., PLS, PCR and HPLC, were found to be suitable and can be successfully used for the determination of the PEPH, PCM, GNF, CPM and BRM in pharmaceutical tablet formulation as well as for dissolution study.Â

STABILITY INDICATING HPTLC METHOD FOR DETERMINATION OF CLEVIDIPINE BUTYRATE IN SYNTHETIC MIXTURE

Objective: To develop and validate stability indicating HPTLC method for determination of clevidipine butyrate in synthetic mixture.Methods: The present study deals with development and validation of stability indicating HPTLC method for estimation of clevidipine butryate. Chromatographic separation was performed on aluminum plate pre coated with Silica Gel 60 F254 using toluene: ethyl acetate (8:2) as mobile phase. TLC scanner was set at wavelength of 370 nm.Results: Retention factor Rf of clevidipine was found to be 0.49. The method was validated as per ICH guidelines. Calibration curve was in the range of 1000-6000ng/band. The correlation coefficient was found to be 0.999. The precision expressed by RSD was less than 2%. The accuracy of method was confirmed by recovery studies using standard addition method and recovery was found to be 99.03-99.57%. The drug was subjected to ICH prescribed hydrolytic, oxidative, photolytic and thermal stress conditions. Clevidipine and its degradation products were well resolved under experimental conditions. The method was validated according to ICH guidelines. The drug showed significant degradation in alkaline and acidic condition and slight degradation in oxidative condition. The drug was stable in thermal condition.Conclusion: A new, Simple, Accurate, Precise, Sensitive and economic stability indicating HPTLC method has been developed and validated for the determination of clevidipine and can be employed for stability indicating analysis