Narrow QRS Tachycardia with Alternate Wide QRS Beats: What is the Mechanism?

A 44-year old lady underwent electrophysiology study for recurrent palpitations and documented narrow QRS regular tachycardia. The baseline ECG showed subtle preexcitation that was easily manifest on atrial pacing. The retrograde atrial activation sequence during ventricular pacing was eccentric suggesting retrograde conduction over the accessory pathway. A regular narrow QRS tachycardia with cycle length 280 ms was easily inducible on programmed atrial stimulation. The earliest ventricular activation during sinus rhythm & atrial pacing, and the retrograde atrial activation during ventricular pacing & tachycardia were diagnostic of left free wall accessory pathway and orthodromic atrioventricular reciprocating tachycardia (AVRT). During an episode of tachycardia, an ablation catheter was placed in the region of the lateral mitral annulus using retrograde trans-aortic approach. Once the ablation catheter was stabilized in that region, an interesting change in the AVRT was seen with appearance of wide QRS complexes of right bundle branch block (RBBB) morphology and left axis deviation in the alternate beats (Figure 1). The atrial activation sequence during both narrow and wide QRS beats was same with earliest activation in the distal coronary sinus. What is the mechanism of the alternate wide QRS beats during the AVRT

Foundations Failures of Bridges and Geotechnical Investigations

In the present paper two cases of foundation failures due to which the complete bridge structure have failed are reported. The 93m long Palakmati high level brick masonry arch bridge on Hoshangabad - Piparia Road was constructed in year 1910. This bridge has shallow well brick masonry foundation with brick masonry wall type piers. Foundations of piers were on two circular shallow independent wells. The wells are resting on yellow soil. During floods of 1989, the pier No.3 sunk. This brought down 5 spans. Two well foundations were up-rooted. Cracks were developed in other arches also. The 90.5m long submersible R.C.C. trough slab type Mand bridge in 60/8 km on Ambikapur-Pathalgaon Road of 5. 5m width was constructed in the year 1945-46. The bridge has open foundation resting on rock whereas superstructure consist of R.C.C. portal framed structure. The foundation of first pier towards Ambikapur side sunk by about 0. 4m in August 1991. Due to this abrupt settlement the abutment and all the three piers have developed through cracks below the supports and severe cracks in all spans. Geotechnical investigations are carried out in these two cases and remedial measures are suggested for reconstruction of new bridges

Mathematically optimized production, purification and characterization of penicillin G acylase from soil bacterial isolates AA17A and AA17B

260-268This research article deals with production of industrial enzyme penicillin G acylase from soil bacterial isolates namely AA17A and AA17B, which are selected from 80 soil samples. The strains were selected based on qualitative (turbidity) and quantitative (HPLC) test for 6-aminopenicillanic acid (6APA) production. The enzyme was assayed for its activity and optimized for production of enzyme using design of experiments software (DOE) “Design Expert 8.0.7.1”. Optimization of enzyme production of four carbon sources (glucose, glycerol, sucrose and starch), four nitrogen sources (beef extract, tryptone, peptone and yeast extract), for temperature (25°C, 30°C, 35°C and 40°C), four pH (6, 7, 8, 9), four inoculum volumes (2.5 ml, 5.0 ml, 7.5 ml, 10.0 ml) and the phenyl acetic acid (PAA) level  (0.15%, 0.17%, 0.185%, 0.2%). The penicillin acylase activity was enhanced to 1.2 fold under following optimized culture conditions: carbon source - glucose (8%), nitrogen source - beef extract (2%), pH 9.0, temperature 30ºC, phenyl acetic acid 0.185%, inoculum volume 5 ml. Approximately 1.22-fold purification from the initial culture broth was achieved during ammonium sulphate precipitation (70-80%) with a yield of 4.6% enzyme. The specific activity of the final partially purified enzyme was 13.73 IU/mg protein

COUROUPITA GUIANENSIS LEAF CALLUS EXTRACT MEDIATED SYNTHESIS AND ANTIBACTERIAL ACTIVITY OF SILVER NANOPARTICLES.

Objective: Synthesis of varied sized and morphologically distinct silver nanoparticles (AgNPs) using callus/callus extract, and their promising antibacterial and cytotoxicity was reported from very few plant systems. Here, we investigated silver nanoparticle synthetic potential of Couroupita guianensis leaf callus extract and their antibacterial activity.Methods: synthesis of callus mediated silver nanoparticles and characterisation of physical, chemical, and antibacterial activity of AgNPs.Results: Callus extract rapidly reduced silver ions and stabilized nanoparticles have displayed characteristic maximum UV absorbance at 410 nm. SEM and AFM images revealed their spherical morphology and size variation, which is ranged from 30.38 nm to 88.32 nm and were in small aggregates. Capping of AgNPs by the phenolic compounds and proteins revealed from FTIR spectral peaks. Silver nanoparticles displayed significantly high antimicrobial activity against both Gram positive and negative bacterial strains compared to silver ions and gentamicin. This enhanced antimicrobial activity of AgNPs may due their small size leading to efficient molecular contact with cell surface, and uptake and interaction with vital biomolecules.Conclusions: Stable AgNPs were synthesized through reduction and capping of silver ions by polyphenols and proteins present in callus extract. Theenhanced antimicrobial activity of AgNPs may due to their small size leading to efficient molecular contact with the cell surface, penetration, andinteraction, and inactivation of vital biomolecules.Â

Assessing data quality in survey with healthcare providers on COVID-19 and the measures for improving

Background: Social surveys have also been transformed with the advancements in research methods. However, only through appropriate methods, proper planning and procedures the data quality can be ensured.Aim: The aim of the current research is to present the measures taken up in doing survey with healthcare providers of primary health care facilities during the time of COVID-19 and to assess the data quality.Method: The survey was conducted with all 280 medical and paramedical staff in 24 primary healthcare centers of government to understand the preparedness of primary health care facilities in terms of providing a safe working environment to healthcare providers and to prevent the spread of infection while discharging duties during COVID-19. The study used mix mode of data collection by administering telephonic and self-administered questionnaire.  It is a descriptive study based on review of secondary literature and the different measures adopted in the survey to ensure data quality.Result: The variation found in responses to questions related to training, personal fears, challenges and coping mechanism was low, when asked differently in telephonic and self-administered questionnaire. It shows that the measures taken in conducting survey through mix mode of data collection at the time of COVID-19 were effective in overcoming the data quality challenges of COVID-19 to conduct face-to-face study and maintaining data quality of the survey.Conclusion: It can be concluded that proper planning, preparations and precautions were effective in ascertaining the data quality

Gold Nanoparticles with Self-Assembled Cysteine Monolayer Coupled to Nitrate Reductase in Polypyrrole Matrix Enhanced Nitrate Biosensor

We have developed here a novel, highly sensitive and selective nitrate (NO– 3) biosensor by covalent immobilization of nitrate reductase (NaR) in self-assembled monolayer (SAM) of cysteine on gold nanoparticles (GNP)-polypyrrole (PPy) modified platinum electrode. Incorporation of GNP in highly microporous PPy matrix was confirmed by morphological scanning electron microscope (SEM) images. The electrochemical behavior of the NaR modified electrode exhibited the characteristic reversible redox peaks at the potential, –0.76 and –0.62 V versus Ag/AgCl. Further, the GNP-PPy nanocomposite enhanced the current response by 2-fold perhaps by enhancing the immobilization of NaR and also direct electron transfer between the deeply buried active site and the electrode surface. The common biological interferences like ascorbic acid, uric acid were not interfering with the NO– 3 measurement at low concentration levels. This biosensor showed a wide linear range of response over the concentration of NO– 3 from 1 μM to 1 mM, with higher sensitivity of 84.5 nA μM–1 and a detection limit of 0.5 μM. Moreover, the NO– 3 level present in the nitrate-rich beetroot juice and the NO– 3 release from the lipopolysaccharide treated human breast cancer cells were estimated

Preparation and evaluation of mouth dissolving tablets of meloxicam

The aim of the present study was to develop evaluate mouth dissolving tablet of meloxicam. Drug delivery systems became sophisticated as pharmaceutical scientists acquire a better understanding of the physicochemical and biochemical parameters pertinent to their performance. Over the past three decades, mouth dissolving or orally disintegrating tablets have gained considerable attention as a preferred alternative to conventional tablets due to better patient compliance. The most preferrable route of drug administration (e.g. oral) is limited to drug candidate that show poor permeability across the gastric mucosa and those, which are sparingly soluble. A large majority of the new chemical entities and many new existing drug molecules are poorly soluble, thereby limiting their potential uses and increasing the difficulty of formulating bioavailable drug products,so lastlly the purpose of this study was to grow mouth dissolve tablets of Meloxicam. Meloxicam is a newer selective COX-1 inhibitor. These tablets were prepared by wet granulation procedure. The tablets were evaluated for % friability, wetting time and disintegration time. Sublimation of camphor from tablets resulted in better tablets as compared to the tablets prepared from granules that were exposing to vacuum. The systematic formulation approach helped in understanding the effect of formulation processing variables.Keywords: Mouth dissolving tablet; Maloxicam; Bioavailability; NSAI

Preparation and evaluation of mouth dissolving tablets of meloxicam

The aim of the present study was to develop evaluate mouth dissolving tablet of meloxicam. Drug delivery systems became sophisticated as pharmaceutical scientists acquire a better understanding of the physicochemical and biochemical parameters pertinent to their performance. Over the past three decades, mouth dissolving or orally disintegrating tablets have gained considerable attention as a preferred alternative to conventional tablets due to better patient compliance. The most preferrable route of drug administration (e.g. oral) is limited to drug candidate that show poor permeability across the gastric mucosa and those, which are sparingly soluble. A large majority of the new chemical entities and many new existing drug molecules are poorly soluble, thereby limiting their potential uses and increasing the difficulty of formulating bioavailable drug products,so lastlly the purpose of this study was to grow mouth dissolve tablets of Meloxicam. Meloxicam is a newer selective COX-1 inhibitor. These tablets were prepared by wet granulation procedure. The tablets were evaluated for % friability, wetting time and disintegration time. Sublimation of camphor from tablets resulted in better tablets as compared to the tablets prepared from granules that were exposing to vacuum. The systematic formulation approach helped in understanding the effect of formulation processing variables.Keywords: Mouth dissolving tablet; Maloxicam; Bioavailability; NSAI

Cationic Amino Acids Specific Biomimetic Silicification in Ionic Liquid: A Quest to Understand the Formation of 3-D Structures in Diatoms

The intricate, hierarchical, highly reproducible, and exquisite biosilica structures formed by diatoms have generated great interest to understand biosilicification processes in nature. This curiosity is driven by the quest of researchers to understand nature's complexity, which might enable reproducing these elegant natural diatomaceous structures in our laboratories via biomimetics, which is currently beyond the capabilities of material scientists. To this end, significant understanding of the biomolecules involved in biosilicification has been gained, wherein cationic peptides and proteins are found to play a key role in the formation of these exquisite structures. Although biochemical factors responsible for silica formation in diatoms have been studied for decades, the challenge to mimic biosilica structures similar to those synthesized by diatoms in their natural habitats has not hitherto been successful. This has led to an increasingly interesting debate that physico-chemical environment surrounding diatoms might play an additional critical role towards the control of diatom morphologies. The current study demonstrates this proof of concept by using cationic amino acids as catalyst/template/scaffold towards attaining diatom-like silica morphologies under biomimetic conditions in ionic liquids

Finite element simulation of nonlinear convective heat and mass transfer in a micropolar fluid-filled enclosure with Rayleigh number effects

A mathematical model is presented to study the double-diffusive convective heat and mass transfer of a micropolar biofluid in a rectangular enclosure, as a model of transport phenomena in a bioreactor. The vertical walls of the enclosure are maintained at constant but different temperatures and concentrations. The conservation equations for linear momentum, angular momentum, energy and species concentration are formulated subject to appropriate boundary conditions and solved using both finite element and finite difference numerical techniques. Results are shown to be in excellent agreement between these methods. Several special cases of the flow regime are discussed. The distributions for streamline, isotemperature, isoconcentration and (isomicrorotation) are presented graphically for different Lewis number, buoyancy parameter, micropolar vortex viscosity parameter, gyration viscosity parameter, Rayleigh number, Prandtl number and micro-inertia parameter. Micropolar material parameters are shown to considerably influence the flow regime. The flow model has important applications in hybrid aerobic bioreactor systems exploiting rheological suspensions e.g. fermentation