A comparative prospective study to assess the clinical efficacy and safety of pantoprazole monotherapy versus pantoprazole and itopride dual therapy in patients with gastroesophageal reflux disease in a tertiary care hospital

Background: Gastroesophageal reflux disease (GERD) is a common chronic, relapsing condition that carries a risk of significant morbidity and potential mortality from resultant complications. Proton pump inhibitors (PPIs) remained as the main stay in the therapy of GERD but they do not have any role in increasing the tone of lower esophageal sphincter which is the main pathophysiology of GERD. In this regard addition of prokinetic agent like Itopride may be beneficial in improving the symptoms associated with GERD. So the present study has been taken to compare the healing rates of esophagitis and reduction in symptom scores associated with GERD between Pantoprazole monotherapy and Pantoprazole plus Itopride combination.Methods: 100 patients diagnosed with GERD were randomly assigned into two groups, Group A and Group B. Group A received tablet Pantoprazole 40 mg twice daily alone and group B received tablet Pantoprazole 40 mg twice daily and tablet Itopride 50 mg thrice daily 30 minutes before food for 4 weeks. The patients were followed up at the end of 4 weeks and were given the questionnaire to assess the FSSG scores. Endoscopy and FSSG scores were recorded and then the percentage of responders in both groups was compared.Results: Endoscopic evidence of healing of esophagitis was similar in both the groups, 72% in Group A and 74% in Group B. The symptom relief was significantly more in Pantaprozole plus Itopride group 74.5% (4.2±1.6) than Pantaprozole alone 62.5% (6.4±1.1) after 4 weeks (p < 0.001).The occurrence of side effects was less in group B compared to group A (22% vs 30%, p= 0.172).Conclusions: Pantoprazole and combination of Pantoprazole plus Itopride provide more effective endoscopic healing of esophagitis. Pantoprazole and Itopride combination is more efficacious in ameliorating the symptoms of GERD than Pantoprazole alone

Phytoremediation: green to clean environmental heavy metal pollution

Many natural processes and anthropogenic activities lead to the persistent accumulation of non-biodegradable heavy metals in the environment. This contamination further has the potential to enter the food chain by a process called bioaccumulation and further, the concentration of heavy metal raises exponentially from lower to higher trophic levels as it is consumed called biomagnification. With the perspective of the consequences associated with heavy metal toxicity including risks to ecosystem and human health (mutagenic, carcinogenic, and teratogenic), the reclamation of toxic accumulates in soil and water is of paramount importance. Presently, clean-up technologies for heavy metals primarily concentrate on mitigating toxicity using physicochemical and mechanical methods such as soil incineration, excavation, landfilling, soil washing, solidification, and the application of electric fields. However, these are expensive, time-consuming, and also result in destructive changes to soil's physicochemical and biological properties, causing secondary pollution to the soil ecosystem. Therefore, the use of the inherent plant’s ability to absorb ionic compounds even at low concentrations near the soil-root interface can be effectively employed as a strategy to extract and remove or lower the bioavailable toxic metals and this phenomenon is called phytoremediation

Behavioral genomics of honeybee foraging and nest defense

The honeybee has been the most important insect species for study of social behavior. The recently released draft genomic sequence for the bee will accelerate honeybee behavioral genetics. Although we lack sufficient tools to manipulate this genome easily, quantitative trait loci (QTLs) that influence natural variation in behavior have been identified and tested for their effects on correlated behavioral traits. We review what is known about the genetics and physiology of two behavioral traits in honeybees, foraging specialization (pollen versus nectar), and defensive behavior, and present evidence that map-based cloning of genes is more feasible in the bee than in other metazoans. We also present bioinformatic analyses of candidate genes within QTL confidence intervals (CIs). The high recombination rate of the bee made it possible to narrow the search to regions containing only 17–61 predicted peptides for each QTL, although CIs covered large genetic distances. Knowledge of correlated behavioral traits, comparative bioinformatics, and expression assays facilitated evaluation of candidate genes. An overrepresentation of genes involved in ovarian development and insulin-like signaling components within pollen foraging QTL regions suggests that an ancestral reproductive gene network was co-opted during the evolution of foraging specialization. The major QTL influencing defensive/aggressive behavior contains orthologs of genes involved in central nervous system activity and neurogenesis. Candidates at the other two defensive-behavior QTLs include modulators of sensory signaling (Am5HT(7) serotonin receptor, AmArr4 arrestin, and GABA-B-R1 receptor). These studies are the first step in linking natural variation in honeybee social behavior to the identification of underlying genes

Synthesis, characterization and antibacterial activity studies of new 2‑pyrral‑L‑amino acid Schif base palladium (II) complexes.

Three new 2-pyrral amino acid Schif base palladium (II) complexes were synthesized, characterized and their activity against six bacterial species was investigated. The ligands: Potassium 2-pyrrolidine-L-methioninate (L1), Potassium 2-pyrrolidine-L-histidinate (L2) and Potassium 2-pyrrolidine-L-tryptophanate (L3) were synthesized and reacted with dichloro(1,5- cyclooctadiene)palladium(II) to form new palladium (II) complexes C1, C2 and C3, respectively. 1 NMR, FTIR, UV–Vis,elemental analysis and conductivity measurements were used to characterize the products. The antibacterial activities of the compounds were evaluated against Gram-positive Staphylococcus aureus (S. aureus, ATCC 25923), methicillin-resistant Staphylococcus aureus (MRSA, ATCC 33591), Staphylococcus epidermidis (S. epidermidis, ATCC 12228) and Streptococcus pyogenes (S. pyogenes, ATCC 19615) and, gram-negative Pseudomonas aeruginosa (P. aeruginosa, ATCC 27853) and Klebsiella pneumoniae (K. pneumoniae, ATCC 13883) using the agar well difusion assay and microtitre plate serial dilution method. The palladium complexes were active against the selected bacteria with the imidazole ring containing complex C2 and indole heterocyclic ring containing complex C3 showing the highest activity

Analysis of SSR With Three-Level Twelve-Pulse VSC-Based Interline Power-Flow Controller

The interline power-flow controller (IPFC) is a voltage-source-converter (VSC)-based flexible ac transmission system (FACTS) controller for series compensation with the unique capability of power-flow management among the multiline transmission systems of a substation. The reactive voltage injected by individual VSCs can be maintained constant or controlled to regulate active power flow in the respective line. While one VSC regulates the dc voltage, the others control the reactive power flows in the lines by injecting series active voltage. This paper presents the modelling of IPFC with 12-pulse, three-level converters and investigates the subsynchronous-resonance (SSR) characteristics of IPFC for different operating modes. The analysis of SSR is carried out based on eigenvalue analysis and transient simulation of the detailed system. It is illustrated with the help of a case study on a system adapted from the IEEE Second Benchmark Model. The analysis uses both – model (neglecting harmonics in the output voltages of VSCs) and the three-phase model of VSCs using switching functions. While the eigenvalue analysis and controller design is based on the – model, the transient simulation considers both models

Analysis of Subsynchronous Resonance with Three Level Twelve-Pulse VSC based SSSC

This paper presents the analysis and simulation of a series compensated system with a static synchronous series compensator (SSSC) as a part of the total compensation. The objective is to investigate the subsynchronous resonance (SSR) characteristic of the combined system. The IEEE first benchmark model (FBM) is considered for the analysis. The active series compensation is provided by a three level twelve pulse SSSC. The modelling and control details of a three level voltage source converter (VSC) based SSSC are discussed. The analysis of SSR with SSSC is carried out based on a frequency domain method, eigenvalue analysis and transient simulation. The frequency domain method considers the D-Q model of SSSC for the computation of damping torque for a quick check in determining torsional mode stability

Investigation of Subsynchronous Resonance With VSC-Based HVDC Transmission Systems

The HVDC converter control can destabilize torsional modes of nearby turbogenerators. The first experience of HVDC-turbine generator torsional interaction was observed in 1977 during field tests at Square Butte. The development of power semiconductors, specially insulated-gate bipolar transistors and gate turnoff thyristors (GTOs) has led to the small power HVDC transmission based on voltage-source converters (VSCs). The self-commutated VSC-based HVDC installations have several advantages compared to conventional HVDC-based online-commutated current source converter. The main objective of this paper is to investigate and present the detailed analysis of subsynchronous resonance (SSR), arising from a VSC-based HVDC system connected close to generating units. The analysis considers different operating modes of the converters. Based on a case study, it is shown that the dc voltage control mode of VSC operation (rectifier/inverter) close to the generator units can contribute positive damping in the torsional-mode frequency range of interest. The investigations of SSR with VSC-based HVDC is carried out based on linear (damping torque and eigenvalue) analysis and nonlinear transient simulation. While the damping torque, eigenvalue analysis, and controller design are based on the D-Q model, the transient simulation considers the D-Q model and the three-phase detailed model of VSC using switching functions. The influence of the operating modes of the converters and effects of some important parameters, such as effective short circuit ratio and generator rating are investigated

Investigation of SSR characteristics of unified power flow controller

The unified power flow controller (UPFC) is the most versatile flexible ac transmission system (FACTS) controller which can be used to control active and reactive power flows in a transmission line in addition to the bus voltage. The active series compensation is provided by injecting series reactive voltage. The voltage at the two ports of UPF Care regulated by control of shunt current and series real voltage. It also has several operating control modes such as voltage and power regulation, line impedance compensation, etc. This paper presents the analysis and study of sub-synchronous resonance (SSR) characteristics of UPFC. The various combination of operating modes of shunt and series converters are considered for investigating their effect on SSR characteristics.The analysis of SSR with UPFC is carried out based on frequency domain method, eigen value analysis and transient simulation. The frequency domain method considers D-Q model of UPFC for the computation of damping torque for quick check in determining torsional mode stability.The study is performed on IEEE First Benchmark Model (FBM)

Modelling, Control Design and Analysis of VSC Based HVDC Transmission Systems

The development of power semiconductors, specially IGBTs has led to the small power HVDC transmission based on voltage source converters (VSCs). The VSC based HVDC transmission system mainly consists of two converter stations connected by a dc cable. This paper presents the modelling and control design of VSC based HVDC which uses twelve pulse three level converter topology. The reactive current injected by individual VSCs can be maintained constant or controlled to regulate converter bus voltage constant. While one VSC regulates the dc bus voltage the other controls the power flow in the dc link. Each VSC can have up to 4 controllers depending on the operating mode. The controller structure adopted for power controller is of PID type and all other controllers are of PI type. Each operating mode requires proper tuning of controller gains in order to achieve satisfactory system performance. This paper discusses a systematic approach for parameter optimization in selecting controller gains of VSC based HVDC. The analysis of VSC based HVDC is carried using both D-Q model (neglecting harmonics in the output voltages of VSC) and three phase detailed model of VSC using switching functions. While the eigenvalue analysis and controller design is based on the D-Q model, the transient simulation considers both models. The analysis considers different operating modes of the converters

Design and Performance Evaluation of Subsynchronous Damping Controller With STATCOM

A long transmission line needs controllable series as well as shunt compensation for power flow control and voltage regulation. This can be achieved by suitable combination of passive elements and active FACTS controllers. In this paper, series passive compensation and shunt active compensation provided by a static synchronous compensato(STATCOM) connected at the electrical center of the transmission line are considered. It is possible to damp subsynchronous resonance (SSR) caused by series capacitors with the help of an auxiliary subsynchronous damping controller (SSDC) on STATCOM. The objective of this paper is to investigate the SSR characteristics of the system and propose a new design procedure for SSDC based on nonlinear optimization to meet the specifications on the damping torque in the range of critical torsional frequencies. The SSDC uses the Thevenin voltage signal to modulate the reactive current reference of STATCOM. The Thevenin voltage signal is derived from the locally available STATCOM bus voltage and reactive current signals. The STATCOM configurations considered in this paper are 12 pulse, two- and three-level voltage source converter with Type-2 and Type-1 control, respectively. The controller regulates either reactive current (supplied by the STATCOM) or the bus voltage. The 3-phase model of the STATCOM is based on switching functions. By neglecting harmonics in the switching function, D-Q model is derived which is combined with similar models of the other system components for linear analysis. The results of the linearanalysis are validated by carrying out transient simulation based on the detailed nonlinear models. The study is performed on the system adapted from the IEEE First Benchmark Mode