Instabilities and waves in thin films of living fluids

We formulate the thin-film hydrodynamics of a suspension of polar self-driven particles and show that it is prone to several instabilities through the interplay of activity, polarity and the existence of a free surface. Our approach extends, to self-propelling systems, the work of Ben Amar and Cummings [Phys Fluids 13 (2001) 1160] on thin-film nematics. Based on our estimates the instabilities should be seen in bacterial suspensions and the lamellipodium, and are potentially relevant to the morphology of biofilms. We suggest several experimental tests of our theory.Comment: 4 pages, pdflatex, accepted for publication in Phys Rev Let

Percolative shunting on electrified surface

The surface discharge of electrified dielectrics at high humidity is considered. The percolative nature of charge transport in electrets is established. Particular attention is given to the phenomena of adsorption and nucleation of electrically conducting phase in the cause of percolation cluster growth on electrified surface. The critical index of the correlation lenght for percolation cluster is found, and its value is in good agreement with the known theoretical estimations.Comment: 4 pages with 1 figure, revtex, published in Tech. Phys. Lett. 25 (1999) 877-879 with one additional figur

IoT Based Industrial Production Monitoring System Using Wireless Sensor Networks

The objective of the work is to monitoring the production lines in industry using wireless sensor networks. This work presents the benefits of an automated data collection and display system for production lines. It involves wireless sensor networks for monitoring the productions in industry. Condition monitoring reduces human inspection requirements through automated monitoring, reduces maintenance through detecting faults before they escalate and improves safety and reliability. This work can monitor productions using temperature, voltage and current sensors with support of microcontroller. The relay is acts like a switch to monitor the production lines. In this work, Global System for Mobile communication technique is used to transferring the collected data. The collection of data, it is transferred into computerize spreadsheet in the remote office by authorized personnel for reporting purpose. The system will generate an automated report which stays in place and the management only needs to act base on the results. This work is cost effective automatic data collection is the alternative to manual data collection. It significantly improves the accuracy of the valuable reports for the management. It also reduces the time for identifying the fault using this techniqu

DeMalFier: Detection of Malicious web pages using an effective classifier

The web has become an indispensable global platform that glues together daily communication, sharing, trading, collaboration and service delivery. Web users often store and manage critical information that attracts cybercriminals who misuse the web and the internet to exploit vulnerabilities for illegitimate benefits. Malicious web pages are transpiring threatening issue over the internet becaus

Self-organized Pattern Formation in Motor-Microtubule Mixtures

We propose and study a hydrodynamic model for pattern formation in mixtures of molecular motors and microtubules. The steady state patterns we obtain in different regimes of parameter space include arrangements of vortices and asters separately as well as aster-vortex mixtures and fully disordered states. Such stable steady states are observed in experiments in vitro. The sequence of patterns obtained in the experiments can be associated with smooth trajectories in a non-equilibrium phase diagram for our model.Comment: 11 pages Latex file, 2 figures include

Adsorption of Multi-block and Random Copolymer on a Solid Surface: Critical Behavior and Phase Diagram

The adsorption of a single multi-block $AB$-copolymer on a solid planar substrate is investigated by means of computer simulations and scaling analysis. It is shown that the problem can be mapped onto an effective homopolymer adsorption problem. In particular we discuss how the critical adsorption energy and the fraction of adsorbed monomers depend on the block length $M$ of sticking monomers $A$, and on the total length $N$ of the polymer chains. Also the adsorption of the random copolymers is considered and found to be well described within the framework of the annealed approximation. For a better test of our theoretical prediction, two different Monte Carlo (MC) simulation methods were employed: a) off-lattice dynamic bead-spring model, based on the standard Metropolis algorithm (MA), and b) coarse-grained lattice model using the Pruned-enriched Rosenbluth method (PERM) which enables tests for very long chains. The findings of both methods are fully consistent and in good agreement with theoretical predictions.Comment: 27 pages, 12 figure

Two-Component Fluid Membranes Near Repulsive Walls: Linearized Hydrodynamics of Equilibrium and Non-equilibrium States

We study the linearized hydrodynamics of a two-component fluid membrane near a repulsive wall, via a model which incorporates curvature- concentration coupling as well as hydrodynamic interactions. This model is a simplified version of a recently proposed one [J.-B. Manneville et al. Phys. Rev. E, 64, 021908 (2001)] for non-equilibrium force-centres embedded in fluid membranes, such as light-activated bacteriorhodopsin pumps incorporated in phospholipid (EPC) bilayers. The pump/membrane system is modeled as an impermeable, two-component bilayer fluid membrane in the presence of an ambient solvent, in which one component, representing active pumps, is described in terms of force dipoles displaced with respect to the bilayer midpoint. We first discuss the case in which such pumps are rendered inactive, computing the mode structure in the bulk as well as the modification of hydrodynamic properties by the presence of a nearby wall. We then discuss the fluctuations and mode structure in steady state of active two-component membranes near a repulsive wall. We find that proximity to the wall smoothens membrane height fluctuations in the stable regime, resulting in a logarithmic scaling of the roughness even for initially tensionless membranes. This explicitly non-equilibrium result, a consequence of the incorporation of curvature-concentration coupling in our treatment, also indicates that earlier scaling arguments which obtained an increase in the roughness of active membranes near repulsive walls may need to be reevaluated.Comment: 39 page Latex file, 3 encapsulated Postscript figure

QUALITY BY DESIGN-BASED OPTIMIZATION AND VALIDATION OF NEW REVERSE PHASE-HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY METHOD FOR SIMULTANEOUS ESTIMATION OF LEVOFLOXACIN HEMIHYDRATE AND AMBROXOL HYDROCHLORIDE IN BULK AND ITS PHARMACEUTICAL DOSAGE FORM

ABSTRACTObjective: Innovative application of quality by design (QbD) technique for simultaneous estimation of levofloxacin and ambroxol hydrochloride (HCL)in bulk and its pharmaceutical dosage form using reverse phase-high-performance liquid chromatography (RP-HPLC) method.Method: A method has been developed for the separation of levofloxacin and ambroxol HCL using RP-HPLC on C18 column (250 4.6 mm, 5 ml) withultraviolet detection at 306 nm. Experimental designs were applied for multivariate optimization of the experimental conditions of RP-HPLC method.Three independent factors: Acetonitrile content in the mobile phase composition, buffer pH, and flow rate were used to design mathematical models.Here, central composite design (CCD) experimental design was used to study the response surface technique and to study in depth the effects ofthese independent factors. Derringer's desirability function was applied to simultaneously optimize the retention time of last eluting peak (ambroxolhydrochloride) and resolution between levofloxacin and ambroxol hydrochloride.Result and Discussion: The predicted optimum assay condition consisted of acetonitrile, potassium dihydrogen phosphate buffer (pH 5.00;potassium dihydrogen phosphate), and methanol in a proportion of 20:70:10% v/v, respectively, as the mobile phase at a flow rate of 1.2 ml/minute.Using this optimum condition, baseline separation of both drugs with good resolution and a run time of <5 minutes were achieved. The optimizedassay condition was validated according to the ICH guidelines to confirm specificity, linearity, accuracy, and precision.Keywords: Levofloxacin, Ambroxol hydrochloride, Experimental design, Response surface methodology, Derringer's desirability, Quality by designapproach