Application of self -assembled ultrathin film coatings to stabilize enzyme encapsulation and activity in alginate microspheres

Alginate-based hydrogels have been used for the encapsulation of a variety of materials, including enzymes, proteins, and cells for a wide range of applications from drug delivery to biosensors and bioreactors. However, due to the high porosity of the matrix, it has been increasingly difficult to retain macromolecules inside the alginate matrix, leading to loss in functionality over time. In an effort to improve the stability for long-term biosensor use, this work investigated layer-by-layer self-assembly as a potential technique to provide a diffusion barrier to an encapsulated macromolecule. Alginate microspheres (∼2–50μm radius) were fabricated using an emulsification technique, and were ionically crosslinked with calcium ions and used for the encapsulation of macromolecules including dextran and the enzyme glucose oxidase. Stepwise-assembled polyelectrolyte nanofilm coatings of different composition and thickness were then formed on the microspheres, and the loss of enzyme was monitored over one week. The total loss of encapsulated material was reduced to less than 15% with the application of a single {PAH/PAA} coating, in comparison to ∼50% loss observed with uncoated and {PDDA/PSS}-coated microspheres. The activity of the encapsulated enzyme was also tested over twelve weeks, and it was found that {PAH/PSS}-coated spheres retained more than 84% of their initial activity after twelve weeks, whereas uncoated and {PDDA/PSS}-coated microspheres retained less than 20% of initial activity after twelve weeks. The activity was further stabilized when a chemical conjugation technique with water soluble 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide (EDC) immobilized the enzyme in the alginate matrix. More than 90% activity retention was observed for all cases. Finally, novel biocompatible coating materials were used to coat the alginate microspheres to slow release and improve biocompatibility. The enzyme was crosslinked to the alginate matrix using EDC-NHSS conjugation techniques. The experimental results showed that the application of single layer thin films to the alginate microspheres was effective in reducing loss of the encapsulated enzyme from the microspheres with more than 80% enzyme retention reported for monolayer coatings and more than 95% enzyme retention for multilayer coatings. The encapsulated enzyme was also found to be highly active (\u3e95% retention of activity) inside the uncoated microspheres and coated microspheres, and the activity results were compared over a period of three months. In vitro cytotoxicity tests were completed using 3T3 cells to determine the “optimum” coating material towards biosensor use. Of the coatings tested, chondroitin sulfate, humic acid, PEG bis(amine), and chitosan coatings were found to be suitable for in vivo testing. These results demonstrate that the simple application of ultrathin film coatings to functional micro-systems can be useful in prolonging the usability of the encapsulated material in those templates, thus leading to improved stability and increased longevity for biosensors and bioreactors

A Qos Adaptive Routing Scheme (IGLAR) For Highly Dynamic Vehicular Networks with Support to Service and Priority

This paper proposes an improved geolocation based QoS aware routing algorithm (IGLAR), which focuses on identifying optimal paths for effective routing in highly dynamic mobile ad hoc network such as VANET based on vehicular traffic at cross roads over a static high way lane. The process of selection and utilizing the optimal QoS route gets updated on transmission. IGLAR works on route identification, route binding, update and deletion process based on the validation of adaptive QoS metrics, before the optimal route selection process between source and destination. This research work discusses on the survey and analysis the performance of GPSR [9], AODV [8], DYMO [12] and proposed scheme based on simulation test beds and scenario mapping using VanetMobiSim with NS-3 simulator. The proposed routing scheme IGLAR has been designed and implemented as per the DSRC specifications [13] and IEEE 802.11p MAC. Keywords: VANET, GPSR, AODV, DYMO, VanetMobisi

CORRELATION OF CONCEPT OF AMA AND FREE RADICAL THEORY

Majority of the endogenous disease begins with the formation of Ama in the body. It has tremendous capacity to vitiate the Doshas and disturbing the homeostasis (Dhatu-samya). Ama is the resultant of improper digestion or partially digestion of the food particle due to hypofunction of Jatharagni and also due to accumulation of mala in the body and also considered as Prathamdoshadusti. It may be considered as partially or incompletely metabolized Dhatu in case of Dhatvagnimandya. In modern parameters, Ama is supposed to be deadly Free radical. Free radical is an atom/molecule that contains one or more unpaired electron, which requires neutralization by free radical scavengers. Ama is not a single entity but is a generalized term, which can be applied to many malformed substances in the body. This Ama is responsible for the production of various diseases. In the same way, free radicals are also found to be the root cause of many diseases. Here we discuss about properties and qualities in both entities, which are similar and dissimilar, also whether free radicals can be considered under Ama. The present article attempts to correlate the most recent concept of todays i. e. free radical concept with that of the concept of Ama, described in research for remedies from Ayurvedic research, which may be helpful in the presentation and care of free radicals mediated disease

Effect of Global Warming on Indian Agriculture

Agriculture is the backbone of Indian economy which in turn relies on the monsoon season. The Intergovernmental Panel on Climate Change (IPCC) projected that the global mean surface temperature will likely rise and may result into uneven climatic changes such as irregular rainfall patterns, increased surface temperature and elevated CO2 content in the atmosphere. Research studies indicate that weathering parameters influence strongly (67%) compared to other factors like soil and nutrient management (33%) during the cropping season. Researchers have confirmed that crop yield falls by 3-5% for every 1°F increase in the temperature. Present study shows that the crop production is dependent on temperature and shows a funnel shape for all the seasons. At lower temperature both the properties are almost linearly correlated, whereas at higher temperatures, it increases but with large scattering. The findings may be helpful to study the effect of climate change on the crop production

Development of WC-Feal Composite by Stir Casting Method

In this paper author make an effort to develop a new material for fulfill the need of present requirement. This material is developed by the using of stir casting method. A AMMC’s composite are developed to fulfill the need of present requirements. This composite material is prepared by the use of 3 metals. These metals are iron (Fe), aluminum (Al) and tungsten carbide (WC).Thus this composite come under metal matrix composite. This composite is WC – FeAl composite. This is prepared by the use of stir casting method. The base metals are iron and aluminum. These are having equal quantity by weight. In this the sample is prepared by the change the of percentage reinforcement. This is varying from 0 to 3%. A test is conduct to check their tensile strength as well as compressive strength. By these test it is confirm that with the increase the percentage of reinforcement in the composite their tensile strength is decrease but their compressive strength is increase

Use of Implantable Loop Recorders to Unravel the Cause of Unexplained Syncope

AbstractSyncope is a symptom of many underlying disease states, which range from the relatively benign to the life threatening. There are numerous investigations done for patients with recurrent unexplained syncope which may have very low yield when it comes to making a definitive diagnosis. Recently, the implantable loop recorder (ILR) for continuous monitoring of the cardiac rhythm has been launched in India. This review will briefly discuss these current availabel strategies and focus on the usefulness of an ILR in the definitive diagnosis and treatment of patients with a recurrent unexplained syncope

Measurement of Cloud Properties Using a Self-Designed Cloud Chamber

Present paper examines the dependency of ambient parameters such as humidity, and turbulence to determine the conditions on raindrop formation with the help of a self-designed cloud chamber. The research methods are experimental and observational in nature, where atmospheric phenomena are recreated through the usage of appropriate substitutes. Miniature droplets were created inside a box-like setup through the use of dry ice to cool the water vapor rising up, so as to create suspended water droplets, and to induce precipitation of heavier droplets. The experiment resulted in the creation of precipitated droplets, which were found at the base of the chamber at 99-100% relative humidity. The suspended droplets were used to study factors such as luminosity and variation of droplet sizes with turbulence. It was found that up to 14.4 m/s of turbulence, the droplet sizes increase with an increase in turbulence, with the luminosity decreasing with increase in turbulence. The gaussian profile of droplet size distribution has also been obtained, with a standard deviation of 2.83, 3.01 and 3.18 for low, medium and high turbulence speeds respectively. The experiment can be extended to incorporate a higher number of variables, so as to include a wider range of atmospheric phenomena.Comment: 12 Pages, 5 figures, 5 table

miR-135a targets IRS2 and regulates insulin signaling and glucose uptake in the diabetic gastrocnemius skeletal muscle

AbstractAlthough aberrant miRNA signatures are associated with diabetes, yet, the status and role of altered miRNAs in the diabetic skeletal muscle is currently poorly understood. Here, we report that 41 miRNAs are altered in the diabetic gastrocnemius skeletal muscle and of these, miR-135a that is identified as a critical regulator of myogenesis, is significantly up-regulated. IRS2 is predicted as its potential putative target and its levels are down-regulated in the diabetic gastrocnemius skeletal muscle. In C2C12 cells, while miR-135a levels decreased during differentiation, IRS2 levels were up-regulated. miR-135a significantly reduced IRS2 protein levels and its 3′UTR luciferase reporter activity and these were blunted by the miR-135a inhibitor and mutation in the miR-135a binding site. Knock-down of endogenous miR-135a levels increased IRS2 at the mRNA and protein levels. miR-135a also attenuated insulin stimulated phosphorylation and activation of PI3Kp85α and Akt and glucose uptake. miR-135a levels were also found to be elevated in the human diabetic skeletal muscle. In-vivo silencing of miR-135a alleviated hyperglycemia, improved glucose tolerance and significantly restored the levels of IRS2 and p-Akt in the gastrocnemius skeletal muscle of db/db mice without any effect on their hepatic levels. These suggest that miR-135a targets IRS2 levels by binding to its 3′UTR and this interaction regulates skeletal muscle insulin signaling

Does Virtualization Capability Maturity Influence Information Systems Development Performance? Theorizing The Non-Linear Payoffs

Firms are increasingly relying on digital transformation and virtualization of physical IT assets to develop information systems projects. However, the assessment of this virtualization on the performance of information systems development (ISD) projects is still unclear. Drawing upon the theories of radical innovation and process virtualization, we develop and empirically test a research model describing the relationships of virtualization capability maturity (VCM) with ISD project performance. Our findings show inverted U-shaped relationships of VCM with both ISD process and product performance. Interestingly, ISD projects achieve performance improvements as they progress incrementally from VCM levels of 0 to 2, but at VCM level 3 performance declines. Also, we observe that at higher levels of VCM, ISD process performance declines more rapidly than ISD product performance and the resources spent on ISD project execution increases non-linearly with increasing levels of VCM. Implications of these results are discussed