Sorptive removal of ciprofloxacin hydrochloride from simulated wastewater using sawdust: Kinetic study and effect of pH

The present work describes dynamic uptake of the antibiotic drug ciprofloxacin hydrochloride (CH), by using a cost-effective agricultural by-product . sawdust (SD). The sawdust was characterised by FTIR and SEM analysis. The sorbent particles were highly porous with average pore diameter of nearly 10 ƒÊm. The optimum pH and solid/liquid ratio for sorption of CH were found to be 5.8 and 2.0, respectively. The dynamic drug uptake data was applied to various kinetic models and their order of fitness was found to be pseudo second order > Elovich equation > power function model, as indicated by their regression values. The experimental equilibrium uptake values (qe) were in close agreement with those evaluated from the pseudo second order equation for initial sorbate concentrations of 10 and 20 mgE.-1 at 33‹C. The drug uptake mechanism was found to be attractive non-electrostatic interactions, involving H-bonding interactions between H atoms and other electronegative species such as F, O and N of the drug molecule. The mechanism is discussed on the basis of pHpzc of sawdust and zwitterionic nature of drug CH. Mass transfer analysis was carried out using the drug uptake data obtained with sorbate concentrations of 10 and 20 mgE.-1. The used sorbent could be regenerated using 1.0 molE.-1 HCl solution with a regeneration efficiency of nearly 85%

The adsorptive removal of a cationic drug from aqueous solution using poly (methacrylic acid) hydrogels

This study describes adsorptive removal of the antibiotic drug ciprofloxacin hydrochloride from simulated water using poly(methacrylic acid) (PMAA) as adsorbent. The adsorbent was characterised by various instrumental techniques such as X-ray diffraction (XRD), differential scanning calorimetry (DSC), and Fourier transform infrared (FTIR) spectroscopy. The adsorption equilibrium data, as studied at 3 temperatures, namely, 15, 25 and 37°C, were best interpreted by the Langmuir adsorption isotherm model.  Moreover, an increase in temperature reduces drug uptake. A pH of the adsorption system in the range of 5.0 to 8.0 causes maximum adsorption of the drug. The presence of drug molecules in the adsorbent particles was shown by various techniques: X-ray diffraction (XRD), differential scanning calorimetry (DSC), Fourier transform infrared (FTIR) spectroscopy and  scanning electron microscopy (SEM) analysis. Antibacterial studies also  reveal the adsorption of the drug from solution.Keywords: Adsorption, ciprofloxacin, Langmuir isotherm, X-ray diffraction, Fourier transform infrared (FTIR) spectroscop

Interface driven magnetoelectric effects in granular CrO2

Antiferromagnetic and magnetoelectric Cr2O3-surfaces strongly affect the electronic properties in half metallic CrO2. We show the presence of a Cr2O3 surface layer on CrO3 grains by high-resolution transmission electron microscopy. The effect of these surface layers is demonstrated by measurements of the temperature variation of the magnetoelectric susceptibility. A major observation is a sign change at about 100 K followed by a monotonic rise as a function of temperature. These electric field induced moments in CrO3 are correlated with the magnetoelectric susceptibility of pure Cr2O3. This study indicates that it is important to take into account the magnetoelectric character of thin surface layers of Cr2O3 in granular CrO2 for better understanding the transport mechanism in this system. The observation of a finite magnetoelectric susceptibility near room temperature may find utility in device applications.Comment: Figure 1 with strongly reduced resolutio

Prolongation of the QT Interval and Post-Extrasystolic Augmentation of the TU-Wave During Emotional Stress

We present a case of a 25-year-old woman with multiple blackouts and no structural heart disease, with abnormal T-U waves and borderline QT interval on her resting electrocardiogram. During emotional stress she developed frequent monomorphic ventricular premature beats, with characteristic changes of the sinus complexes immediately following the premature beats, namely augmentation and greater degree of merging of the T and U waves and QTc interval prolongation. The changes alert about the possibility of congenital long QT syndrome, specifically genotype 2 or 1

METRICS FOR LEVERAGING MORE IN CLINICAL DATA MANAGEMENT: PROOF OF CONCEPT IN THE CONTEXT OF VACCINE TRIALS IN AN INDIAN PHARMACEUTICAL COMPANY

The clinical trials data is of critical importance in providing evidence to support a drug or biologic product efficacy and safety. Quality data, productivityand lower product costs are key considerations in drug development process and to maintain competitive edge.  Clinical Data Management(CDM) is a multistage process where various activities must be considered and decision taken in synergy and not sequentially; planned and executed according to the GCP (Good Clinical Practices) guidelines with highest standards.  During the course of development, implementation and standardization of CDM procedures in the context of vaccine trialsin an Indian pharmaceutical company, it emerged that multi-factormetrics based performancemonitoring of critical procedural stepshave synergistic impact in boosting overall in-time progression of the projectand meeting desired data quality.It is important to acknowledge domain knowledge in developing performance metrics by involvingmembers of cross-functional teams. This report summarizes possible methodologies which if adopted are likely to keep the team members updated with the project advancement. The proof of concept, createdin the form of metrics designed to drive performance improvement through appropriate levels of internal controls and characterizing progress made under each criteria, is expected to improve overall productivity by accomplishing the aim with desired quality and within stipulated time-frameby mitigating the errors.Key-words:Clinical Data Management (CDM), Indian Good Clinical Practices(GCP), CDM Metric

Formation of finite antiferromagnetic clusters and the effect of electronic phase separation in Pr{_0.5}Ca{_0.5}Mn{_0.975}Al{_0.025}O{_3}

We report the first experimental evidence of a magnetic phase arising due to the thermal blocking of antiferromagnetic clusters in the weakened charge and orbital ordered system Pr{_0.5}Ca{_0.5}Mn{_0.975}Al{_0.025}O{_3}. The third order susceptibility (\chi_3) is used to differentiate this transition from a spin or cluster glass like freezing mechanism. These clusters are found to be mesoscopic and robust to electronic phase separation which only enriches the antiphase domain walls with holes at the cost of the bulk, without changing the size of these clusters. This implies that Al substitution provides sufficient disorder to quench the length scales of the striped phases.Comment: 4 Post Script Figure

Mathematical model for predicting solidification and cooling of steel inside mould and in air

A two-dimensional mathematical model has been developed to describe the solidification and cooling of steel inside the mould after teeming and in the air after stripping. Partial differential equations describing the processes have been discretized using control volume approach. The discretization equations obtained are of Tri-diagonal matrix form, which have been solved using well known Tri-diagonal matrix algorithm (TDMA) and Alternate direction implicit (ADI) solver. The model has been validated by measuring surface temperatures of mould and ingot using Infrared thermo-vision scanner. This is then used to compute charging temperature and solidification status of ingot as function of track time and type of ingot

Graphene oxide for electrochemical sensing applications

By exploiting the presence of abundant carboxylic groups (–COOH) on graphene oxide (GO) and using EDC–NHS (1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride–N-hydroxysuccinimide) chemistry to covalently conjugate protein molecules, we demonstrate a novel electrochemical immunosensor for detection of antibody–antigen (Rabbit IgG–AntiRabbit IgG) interactions. The interactions were verified using Electrochemical Impedance Spectroscopy (EIS). Although GO is known to be a poor conductor, the charge transfer resistance (RP) of a GO modified glassy carbon electrode (GCE) was found to be as low as 1.26 Ω cm2. This value is similar to that obtained for reduced graphene oxide (RGO) or graphene and an order of magnitude less than bare GCE. The EIS monitored antibody–antigen interactions showed a linear increase in RP and the overall impedance of the system with increase of antibody concentration. Rabbit IgG antibodies were detected over a wide range of concentrations from 3.3 nM to 683 nM with the limit of detection (LOD) estimated to be 0.67 nM. The sensor showed high selectivity towards Rabbit IgG antibody as compared to non-complementary myoglobin. RGO modified GCE showed no sensing properties due to the removal of carboxylic groups which prevented subsequent chemical functionalization and immobilization of antigen molecules. The sensitivity and selectivity achievable by this simple label free technique hint at the possibility of GO becoming the electrode material of choice for future electrochemical sensing protocols