Antibacterial Performance Evaluation of Silver Coated River Sand for Water Decontamination Application

The presence of microbes in drinking water is a serious health hazard demanding immediate attention. Silver is known for centuries for its highly effective antimicrobial properties against a variety of microorganisms. Sand is a natural filter media that is widely used in water purification systems for the removal of dirt and suspended matter from water. Hence the development of additional antimicrobial features in commonly used filter material i.e. sand by coating with silver is an alternative technology for providing a safe drinking-water free from microbes. The present study was performed to develop a cost-effective material with antimicrobial properties by coating locally available river sand with silver. The coated material was subsequently used for its antimicrobial performance by using standard methods. To perform the tests E.coli was isolated from wastewater by using standard microbiological protocols. Thereafter, a biochemical test and antibiotic sensitivity assay were performed. Synthesised silver-coated sand was tested for its antibacterial activity against E.coli through the agar well diffusion method. The results showed a zone of clearance ≥40 mm with 700 mg of synthesised sample. To further determine the efficacy of developed material against E.coli load in artificially contaminated water, experiments were conducted by passing contaminated water through the material stuffed inside a hollow tube filter. A colony count reduction of 86.67 per cent was observed on passing 1000 ml of 3x103 CFU/ml contaminated water through the filter. The present study suggests that additional functionality of microbial reduction can be introduced in the sand through the silver coating. The developed material can be effectively used for the removal of fecal coliforms (E.coli) present in water bodies at an effective cost in addition to the removal of traditional impurities like dirt and suspended materials

The role of flow geometry in influencing the stability criteria for low angular momentum axisymmetric black hole accretion

Using mathematical formalism borrowed from dynamical systems theory, a complete analytical investigation of the critical behaviour of the stationary flow configuration for the low angular momentum axisymmetric black hole accretion provides valuable insights about the nature of the phase trajectories corresponding to the transonic accretion in the steady state, without taking recourse to the explicit numerical solution commonly performed in the literature to study the multi-transonic black hole accretion disc and related astrophysical phenomena. Investigation of the accretion flow around a non rotating black hole under the influence of various pseudo-Schwarzschild potentials and forming different geometric configurations of the flow structure manifests that the general profile of the parameter space divisions describing the multi-critical accretion is roughly equivalent for various flow geometries. However, a mere variation of the polytropic index of the flow cannot map a critical solution from one flow geometry to the another, since the numerical domain of the parameter space responsible to produce multi-critical accretion does not undergo a continuous transformation in multi-dimensional parameter space. The stationary configuration used to demonstrate the aforementioned findings is shown to be stable under linear perturbation for all kind of flow geometries, black hole potentials, and the corresponding equations of state used to obtain the critical transonic solutions. Finally, the structure of the acoustic metric corresponding to the propagation of the linear perturbation studied are discussed for various flow geometries used.Comment: 13 pages. 5 figure

Geomorphology, hydrology and human-environment interactions in the Kosi megafan, India

The continuing channel modification and change in the course of the River Kosi have got a greater implication on the geomorphic evolution processes within its megafan surface. A considerable portion of the land in Kosi megafan remains flooded and later waterlogged every year, a phenomenon that has been exacerbated by the rapid development of roads and railroads. Crop yields are also lowest in parts of the megafan where waterlogging is a bigger problem. This research applies GIS and remote sensing techniques to examine the Kosi channel change from 1975-2015 and map waterlogging and transport network driven ‘disconnectivity’ of the Kosi megafan located in the Indo-Gangetic Plains, India from 2005-2015. This study also used semi-structured interviews of 960 farm-households from four case studies to analyze farm-related changes, especially due to waterlogging and identify factors responsible for a farmer’s adaptation to waterlogging stress from 2014-2015. The findings reveal that there have been substantial changes in the main Kosi channel. The massive development in the road-rail transport network along with the increase in the minor channels within the megafan have led to staggering increase in transport-river intersections and foster both seasonal and permanent waterlogging. The case studies suggest that 90% of the farmers have made changes to their farms due to waterlogging and other factors associated with that. The study also shows that there are limits to adaptation, which are caused by barriers of available technology, knowledge and institutional frameworks. These barriers undermine the effectiveness of the initiatives promoted both at the national as well as local level

Troger's base molecular scaffolds in dicarboxylic acid recognition

Artificial receptors (1−5) have been designed and synthesized from simple precursors. The chain length selectivity studies of dicarboxylic acids within the cavities of new fluorescent Troger's base molecular frameworks (1−3) have been carried out with a critical examination of their role of rigidity as well as flexibility in selective binding in comparison to receptor 5. The chiral resolution of the racemic Troger's base receptors (1 and 2) by chiral recognition with (+)- camphoric acid using hydrogen-bonding interactions has been studied

Pilot study indicate role of preferentially transmitted monoamine oxidase gene variants in behavioral problems of male ADHD probands

Abstract Background Attention deficit hyperactivity disorder (ADHD) is an etiologically complex childhood onset neurobehavioral disorder characterized by age-inappropriate inattention, hyperactivity, and impulsivity. Symptom severity varies widely and boys are diagnosed more frequently than girls. ADHD probands were reported to have abnormal transmissions of dopamine, serotonin, and/or noradrenaline. Monoamine oxidase A (MAOA) and B (MAOB), mitochondrial outer membrane bound two isoenzymes, mediate degradation of these neurotransmitters and thus regulating their circulating levels. Case-control analyses in different populations, including Indians, suggested involvement of MAOA and MAOB genes in the etiology of ADHD. Due to high heritability rate of ADHD, we tested familial transmission of MAOA and MAOB variants to ADHD probands in 190 nuclear families having ADHD probands from Indo-Caucasoid ethnicity. Methods Subjects were recruited following the Diagnostic and Statistical Manual of Mental Disorders-4th edition (DSM-IV). Appropriate scales were used for measuring the behavioral traits in probands. Genotyping was performed through PCR-based amplification of target sites followed by DNA-sequencing and/or gel-electrophoresis. Data obtained were analyzed by family based statistical methods. Results Out of 58 variants present in the analyzed sites only 15 were found to be polymorphic (30 bp-uVNTR, rs5906883, rs1465107, rs1465108, rs5905809, rs5906957, rs6323, rs1137070 from MAOA and rs4824562, rs56220155, rs2283728, rs2283727, rs3027441, rs6324, rs3027440 from MAOB). Statistically significant maternal transmission of alleles to male probands was observed for MAOA rs5905809 ‘G’ (p = 0.04), rs5906957 ‘A’ (p = 0.04), rs6323 ‘G’ (p = 0.0001) and MAOB rs56220155 ‘A’ (p = 0.002), rs2283728 ‘C’ (p = 0.0008), rs2283727 ‘C’ (p = 0.0008), rs3027441 ‘T’ (p = 0.003), rs6324 ‘C’ (p = 0.003), rs3027440 ‘T’ (p = 0.0002). Significantly preferential maternal transmissions of different haplotype combinations to male probands were also noticed (p < 0.05), while female probands did not reveal such transmission bias. Behavioral traits of male probands exhibited significant association with gene variants. Age of the mother at pregnancy also revealed association with risk variants of male probands. Conclusions It may be inferred that the MAOA and MAOB variants may contribute to the etiology of ADHD in the Indo-Caucasoid population and could be responsible for higher occurrence of ADHD in the boys

Study of time irrigation on grow, development and water comsuption in potted Dinathus caryophyllus L.

Un experimento de riego de clavel en maceta bajo invernadero-umbráculo fue diseñado para conocer la influencia de la hora de riego sobre el crecimiento, desarrollo y la eficiencia de la utilización del agua.Escuela Técnica superior de Ingeniería AgronómicaUniversidad Politécnica de Cartagen