Novel Synergistic Activity of Quercus infectoria Gall Extract with Ceftazidime Against Standard and Multiple Drug Resistant Pseudomonas aeruginosa and Escherichia coli Isolates

Background: Multidrug resistance pathogens are important heath challenges. In this study, the antibacterial activity of 20 plant extracts was tested against standard as well as 20 multidrug-resistant (MDR) strains of Pseudomonas aeruginosa and Escherichia coli. The most active plant extract (Quercus infectoria) was selected for the synergistic activity assay. Methods: Plant extracts were prepared by maceration using water, methanol and ethanol. The antibacterial activity of extracts was determined by both broth and agar dilution methods. The synergistic activity of QIG with ceftazidime (CAZ) was evaluated by checker board assay. Antioxidant activity was determined by colorimetric Ferric reducing antioxidant power (FRAP) assay. Results: Only the methanol extract of QIG inhibited the growth of all the bacterial strains at a concentration of 1000 µg/mL. Other active extracts were Myrtus communis and Eucalyptus globulus inhibiting the growth of most bacterial strains tested at 2000 µg/ mL. In checker board assay, the minimum inhibitory concentration (MIC) to both QIG extract and CAZ was reduced. The MIC of CAZ was reduced from 64-4096 µg/mL to 4 µg/mL for P. aeruginosa and to 16 µg/mL for E. coli isolates. Conclusion: The QIG extract exhibited potent antioxidant activity determined by FRAP assay. The result of this study showed a strong synergistic activity between QIC and CAZ on P. aeruginosa and E. coli. The activity within ethyl acetate-methanol (7:3) fraction indicates that the active components of the plant have a semi-polar nature and further work with this fraction may lead to understanding the mechanism of this synergistic activity.

The Influence of Martensitic Intercalations in Magnetic Shape Memory NiCoMnAl Multilayered Films

Hysteresis and transformation behavior were studied in epitaxial NiCoMnAl magnetic shape memory alloy thin films with varying number martensitic intercalations (MIs) placed in between. MIs consists of a different NiCoMnAl composition with a martensitic transformation occurring at much higher temperature than the host composition. With increasing number of intercalations, we find a decrease in hysteresis width from 17 K to 10 K. For a large difference in the layers thicknesses this is accompanied by a larger amount of residual austenite. If the thicknesses become comparable, strain coupling between them dominates the transformation process, which manifests in a shift of the hysteresis to higher temperatures, splitting of the hysteresis in sub hysteresis and a decrease in residual austenite to almost 0%. A long-range ordering of martensite and austenite regions in the shape of a 3D checker board pattern is formed at almost equal thicknesses.

Love Wave Group Velocity Tomography of India, Himalaya and Tibet

<p>We present Love wave group velocity tomography calculated from broadband waveform data from Indian seismograph networks and global dataset downloaded from the IRIS-DMC. We first calculate path average 1-D fundamental mode Love wave group velocity between 10 s and 120 s period of the Transverse component of the seismograms. Then we combine these 1-D path average measurements using linear tomographic inversion, assuming great circular arc propagation, to compute 2-D group velocity map of the region at discrete periods. The region is adaptively parametrized to get high resolution at higher raypath density. We performed checker-board test to ascertain the resolution of the tomography maps and compute ray density map, raypath cross density map, and raypath orientation map to quantitatively analyze the controls of these parameters on the checker board resolution recovery. Tomographic maps at lower period show good correlation to the local geologic structures like low velocity in basins and high velocity in cratons and shields. At mid-period maps high velocity roots of cratons and low velocity in Tibet and Andaman- Burma subduction can be seen. At higher period low velocity in Tibet conforms with previous observations. We will do linear inversion of Love wave group velocity to get 3D SH wave velocity structure of the region.</p>

Omnidirectional 3D Point Clouds Using Dual Kinect Sensors

This paper proposes a registration method for two sets of point clouds obtained from dual Kinect V2 sensors, which are facing each other to capture omnidirectional 3D data of the objects located in between the two sensors. Our approach aims at achieving a handy registration without the calibration-assisting devices such as the checker board. Therefore, it is suitable in portable camera setting environments with frequent relocations. The basic idea of the proposed registration method is to exploit the skeleton information of the human body provided by the two Kinect V2 sensors. That is, a set of correspondence pairs in skeleton joints of human body detected by Kinect V2 sensors is used to determine the calibration matrices, then Iterative Closest Point (ICP) algorithm is adopted for finely tuning the calibration parameters. The performance of the proposed method is evaluated by constructing 3D point clouds for human bodies and by making geometric measurements for cylindrical testing objects.

A Porous Media Function That Mimics the Effect of Discrete Holes

Simulating full-coverage film cooling remains an elusive task for aerodynamicists given the small scale of the holes relative to the duct size where the holes are applied. Source term models were developed to simulate the effect through a perforated surface; however, the documented approaches failed to adequately describe how source term locations within the computational domain were selected. This paper presents a continuous ‘checker-board’ surface function that enables a distributed selection of cells where the source terms are applied; furthermore, the source term strengths applied to cells within a given hole are weighted. A 3:1 aspect ratio S-duct with an 1.5 area ratio exhaust diffuser, and 4% porosity applied to the upstream convex bend was evaluated. Steady-RANS obtained with the realizable k-ε model and source terms derived based on the approach of Andreini et al. (2014) had good pressure distribution, outlet velocity, and coolant mass flow agreement with respect to experiment when the hole diameter was resolved with two nodes. Reducing the computational domain element count by 75% and simulating hole diameters 2.8-times larger with 4% surface porosity gave back pressure and outlet distortion coefficients within grid uncertainty of the finest grid solution; however, local-convex-surface-averaged quantities showed grid dependency.

Radar Cross Section Reduction of Low Profile Fabry-Perot Resonator Antenna Using Checker Board Artificial Magnetic Conductor

This paper presents a novel low profile, high gain Fabry-Perot resonator antenna with reduced radar cross section (RCS). An artificial magnetic conductor which provides zero degree reflection phase at resonant frequency is used as the ground plane of the antenna to obtain the low profile behavior. A checker board structure consisting of two artificial magnetic conductor (AMC) surfaces with antiphase reflection property is used as the superstrate to reduce the RCS. The bottom surface of superstrate is perforated to act as partially reflective surface to enhance the directivity of antenna. The antenna has a 3 dB gain bandwidth from 9.32 GHz to 9.77 GHz with a peak gain of 12.95 dBi at 9.6 GHz. The cavity antenna also has reduced reflectivity with a maximum reduction of 14.5 dB at 9.63 GHz.

Evoked potentials

Evoked potentials (EPs) occur in the peripheral and the central nervous system. The low amplitude signals are extracted from noise by averaging multiple time epochs time-locked to a sensory stimulus. The mechanisms of generation, the techniques for stimulation and recording are established. Clinical applications provide robust information to various questions. The importance of EPs is to measure precisely the conduction times within the stimulated sensory system. Visual evoked potentials to a pattern reversal checker board stimulus are commonly used to evaluate the optic nerve. Auditory evoked potentials following ‘click’ stimuli delivered by a headset are most often used to test the auditory nerve and for prognostication in comatose patients. Somatosensory evoked potentials to electrical stimulation of distal nerves evaluate the peripheral nerve and the lemniscal system, and have various indications from demyelinating diseases to the monitoring of operations and prognosis of comatose patients.