Development of process for the Catalytic Degradation of synthetic polymers.

The objective of this project is to develop the process for catalytic degradation of synthetic polymers . Catalytic degradation of synthetic polymers over various catalysts are performed to obtain hydrocarbons from waste materials. The waste material is provided by the industry . The experiment is carried out by using a specially developed laboratory reactor operating isothermally. Various catalysis are being synthesized for the purpose. Appropriate catalysis may be selected to reduce the reaction temperature , improve the yield of product and selectivity in product formation

Specificity of the cocaine aptamer and its application in measurement of cocaine and metabolites in homogeneous samples for forensic analysis

Detection and quantification of molecules has an enormous importance and potential in the field of scientific development and basic discovery research. Advances in colorimetric techniques, fluorescent labeled probes and biosensor based technologies have resulted in the specific detection and precise quantification of analytes. The effective development of a particular detection method needs optimization in terms of overall speed, efficiency, and accuracy of the sensing system. Current biosensor approaches often rely on cumbersome procedural steps and reagent requirements. Along with the complexity of the assay, the size of the analytical instrument is a deterrent factor for on-site applications. To overcome such disadvantages, novel approaches that challenge traditional methods need to be developed. Today, technological advancements have enhanced the ability of researchers to change the properties of molecules. An in vitro selection and amplification technique, called SELEX, has allowed for the discovery of specific oligonucleotide sequences referred to as \u27aptamers\u27. Synthetic oligonucleotide aptamers display a high specificity and affinity binding to different classes of target molecules. Aptamers can discriminate between closely related targets with subtle structural differences. Currently, considerable efforts are being applied to miniaturize the nucleic-acid based sensor systems and assays for analytical and diagnostic screenings based on fluorescence approaches, calorimetric detections and other biosensing methodologies. The efficacy of aptamer based biosensors has been shown on a number of biosensing platforms and these sensors can provide revolutionary sensitivity for forensic detection and identification of controlled substances. Most of the aptamers used in sensor technologies are modified post selection for their use in analytical, diagnostic, forensic and therapeutic applications. Here we detail the specificity profile of cocaine aptamer including a range of metabolites such as benzoylecgonine (BZE), ecgonine methyl ester (EME), ecgonine ethyle ester (EEE), ecgonine (ECG), cocaethylene (COE), norcocaine (NOR) and anhydroecgonine methyl ester (AME). We tested different variants of cocaine aptamer and determined that the specificity of the aptamers is wider than previously reported. The cocaine aptamer binds to cocaine COC, NOR and COE. Extremely weak affinity was observed for BZE. All variants of cocaine aptamer tested showed uniform specificity but different affinities. We determined the motifs of the cocaine that are important for aptamer recognition. We hypothesized that if the cocaine aptamer binds selectively to cocaine and some of its metabolites then the functional groups that are common to these ligands should indicate the determinants of aptamer recognition. The affinity of the aptamers was tested against cocaine and its natural metabolites and against the unnatural cocaine molecules such as cocaine-tertiary-N-biotin (GK69), cocaine-tertiary-N-Boc (GK68), amethyl cocaine (GK71), dithiomethyl cocaine (GK94) and dihydroxy cocaine (GK66). It was determined if the aptamer recognition of cocaine dependent on the functional groups of cocaine such as benzoyl ester, methyl ester and N-methyl group and also upon the underivitized part of the cocaine molecule. The information of the functional groups important for aptamer recognition will be helpful towards the design of aptamer based analytical methods where the knowledge of steric aspects, such as the geometric shape, and interaction with the functional groups, plays an important role. For diagnostic and analytical assays, such information will help in predicting the ligands that have the potential to cross react, depending upon their structural similarity with cocaine. Further, we report a novel method for the fluorescence based detection of cocaine and cocaine metabolites using a 2-aminopurine (2AP) modified cocaine aptamer. Fluorescence quenching of the 2AP upon cocaine binding was used to detect cocaine and its metabolites. 2AP is a structural analogue of adenine in which the amino group is located at the C2 position instead of the C6 position. 2AP is an important molecule owing to its fluorescence properties and has been used as a reporter in structural studies of oligonucleotides. This molecule is reported to form structurally and thermodynamically similar Watson Crick base pairs with thymine as adenosine. We tested several 2AP substitutions of the cocaine aptamer that provided different fluorescence quenching and affinity profiles. Substitution of 2AP for A at the 23rd position was best suited for the fluorescence detection of cocaine and metabolites in homogeneous samples including 10% urine. Interestingly, 2AP substitution at the 6th position increased the affinity of the cocaine aptamer. The increase in affinity of the aptamer upon 2AP substitution could be due to the perturbation of the aptamer structure by 2AP or to direct interaction of 2AP with the cocaine. The cocaine aptamer has been reported to undergo large structural changes upon cocaine binding. However, in our studies we found relatively small 2AP fluorescence changes in the regions of the aptamer reported to undergo large changes. While the cocaine aptamer can be used for the detection of cocaine and metabolites in homogeneous solutions, the forensic application of this aptamer, especially the detection of cocaine in urine is limited due to its specificity profiles and its low binding affinity

Unrestricted Charging Controllar Design Magnitude

This paper presents to be routine in DC/DC phase of Bi-directional battery charger. The neutral is to analyst the filter latitude that will additional shrink the system cost and capacity. Key area is to moderate current ripple of the charging current which produce will approximately ripple unrestricted charging for batteries. Ripple unrestricted charging will shrink the further warmth triggered by the current ripple and surge the battery life. The filter-centered controller is project to transaction with the latent variability problem carried by a high order filter. The filter-centered technique has the compensations of effortlessly operation and no essential of additional current or voltage sensors. This dc/dc phase communicate converter to ease the charging purpose. Together low pass filter centered controller and nick filter based controller are evaluated and nick filter based controller has improved routine

Unrestricted Charging Controllar Design Magnitude

This paper presents to be routine in DC/DC phase of Bi-directional battery charger. The neutral is to analyst the filter latitude that will additional shrink the system cost and capacity. Key area is to moderate current ripple of the charging current which produce will approximately ripple unrestricted charging for batteries. Ripple unrestricted charging will shrink the further warmth triggered by the current ripple and surge the battery life. The filter-centered controller is project to transaction with the latent variability problem carried by a high order filter. The filter-centered technique has the compensations of effortlessly operation and no essential of additional current or voltage sensors. This dc/dc phase communicate converter to ease the charging purpose. Together low pass filter centered controller and nick filter based controller are evaluated and nick filter based controller has improved routine

Aptamer Functionalized Microcantilever Sensors for Cocaine Detection

A cocaine-specific aptamer was used as a receptor molecule in a microcantilever-based surface stress sensor for detection of cocaine molecules. An interferometric technique that relies on measuring differential displacement between two microcantilevers (a sensing/reference pair) was utilized to measure the cocaine/aptamer binding induced surface stress changes. Sensing experiments were performed for different concentrations of cocaine from 25 to 500 μM in order to determine the sensor response as a function of cocaine concentration. In the lower concentration range from 25 to 100 μM, surface stress values increased proportionally to coverage of aptamer/cocaine complexes from 11 to 26 mN/m. However, as the cocaine concentration was increased beyond 100 μM, the surface stress values demonstrated a weaker dependence on the affinity complex surface coverage. On the basis of a sensitivity of 3 mN/m for the surface stress measurement, the lowest detectable threshold for the cocaine concentration is estimated to be 5 μM. Sensing cantilevers could be regenerated and reused because of reversible thermal denaturation of aptamer

Specificity and ligand affinities of the cocaine aptamer: impact of structural features and physiological NaCl

The cocaine aptamer has been seen as a good candidate for development as a probe for cocaine in many contexts. Here, we demonstrate that the aptamer binds cocaine, norcocaine, and cocaethylene with similar affinities and aminoglycosides with similar or higher affinities in a mutually exclusive manner with cocaine. Analysis of its affinities for a series of cocaine derivatives shows that the aptamer specificity is the consequence of its interaction with all faces of the cocaine molecule. Circular dichroism spectroscopy and 2-aminopurine (2AP) fluorescence studies show no evidence of large structural rearrangement of the cocaine aptamer upon ligand binding, which is contrary to the general view of this aptamer. The aptamer’s affinity for cocaine and neomycin-B decreases with the inclusion of physiological NaCl. The substitution of 2AP for A in position 6 (2AP6) of the aptamer sequence eliminated the effect of NaCl on its affinities for cocaine and analogues, but not for neomycin-B, showing a selective effect of 2AP substitution on cocaine binding. The affinity for cocaine also decreased with increasing concentrations of serum or urine, with the 2AP6 substitution blunting the effect of urine. Its low affinities for cocaine and metabolites and its ability to bind irrelevant compounds limit the opportunities for application of this aptamer in its current form as a selective and reliable sensor for cocaine. However, these studies also show that a small structural adjustment to the aptamer (2AP exchanged for adenine) can increase its specificity for cocaine in physiological NaCl relative to an off-target ligand

Length Dependence thermal conductivity of Zinc-Selenide (ZnSe) and Zinc Telluride (ZnTe)- A combined first principles and Frequency Domain Thermoreflectance (FDTR) study

In this study, we report the length dependence of thermal conductivity (k) of zinc-blende Zinc-Selenide (ZnSe) and Zinc Telluride (ZnTe) for length scales between 10 nm and 10000 nm using first-principles computations based on density-functional theory. k value of ZnSe is computed to decrease significantly from 11.3 W/mK to 1.75 W/mK as the length scale is diminished from 10 nm to 10 nm. k value of ZnTe is also observed to decrease from 10 W/mK to 1.2 W/mK for the same decrease in length. We also measure the k of bulk ZnSe and ZnTe using Frequency Domain Thermoreflectance (FDTR) technique and observed a good agreement between FDTR measurements and first principles calculations for the bulk ZnSe and ZnTe. Understanding of thermal conductivity reduction at nanometer length scales provides an avenue to incorporate nanostructured ZnSe and ZnTe for thermoelectric applications.Comment: 19 pages, 13 figure

Evaluation of metabolic status and milk compositions of indigenous cattle with subclinical mastitis and its amelioration by nutritional supplementations

Indigenous cattle that were in early lactation and positive for subclinical mastitis were allocated into 2 groups; one group was administered with nutrional supplements (50 g mixture of vitamins A, D, E and thiamine, riboflavin, pantothenic acid, biotin, niacin, trisodium citrate dihydrate, methionine, manganese, copper, zinc, cobalt, selenium and live yeasts orally daily for 7 days), while other was kept as negative control. Milk composition of mastitic milk and metabolic status of affected cows were evaluated at day 0 and day 7 post-therapy. On day 0, remarkable alteration in milk composition as well as in metabolic status of affected animals was recorded in comparison to the healthy control. However, the altered nutrional panels as well as milk compositions were ameliorated toward normalcy at day 7 post-therapy in mastitic cows administered with nutrional supplements. At day 7 post-therapy, remarkable improvements in somatic cell count was also recorded in these cows when compared with day 0 values within the group, but the values were still significantly higher than the healthy control. Thus, subclinical mastitis in indigenous cattle could bestow remarkable alterations in milk compositions and metabolic status. The altered metabolic panels and milk compositions can be ameliorated toward normalcy by administering nutritional supplements