Insecticidal activity, Chemical Constituents of Trachyspermum ammi, Withania coagulans and Murraya koenigii ethanloic extracts against Bemisia tabaci

Abstract Whitefly is one of the most widespread agricultural pests in the world. Essential oils might be used to control this insect in an environmentally responsible way. The fumigant, repellent, and anti-oviposition activity of ethanol-extracted essential oils of Trachyspermum ammi, Withania coagulans, and Murraya koenigii against Bemisia tabaci was investigated in this study. In the experiment, three essential oil concentrations (2.5 mg/mL, 5 mg/mL, and 10 mg/mL) were used. Trachyspermum ammi had the highest percentage of whitefly death in laboratory experiments due to its fumigant toxicity; the same tendency was found in contact toxicity and repellent effect. Mortality percent rises as the concentration of essential oil increases with bioassay time. As the concentration of essential oil grows with bioassay time, so does the mortality rate. The most adult whiteflies escaped from the treated plants' greenhouse due to the highest essential oil concentration. The greatest repellency was found with Trachyspermum ammi essential oil at 10 mg/mL. The essential oil had the greatest anti-oviposition efficacy against whiteflies. Trachyspermum ammi possessed the most potent anti-oviposition deterrent, followed by Withania coagulans in second place. Murraya koenigii finished third with moderate anti-oviposition, which affects the number of eggs produced in comparison to the control. As a consequence, these three oils might be used as an effective and environmentally acceptable bio-insecticide to control B. tabaci.

Parallel integral projection transform for straight electrode localization in 3-D ultrasound images

In surgical practice, small metallic instruments are frequently used to perform various tasks inside the human body. We address the problem of their accurate localization in the tissue. Recent experiments using medical ultrasound have shown that this modality is suitable for real-time visualization of anatomical structures as well as the position of surgical instruments. We propose an image-processing algorithm that permits automatic estimation of the position of a line-segment-shaped object. This method was applied to the localization of a thin metallic electrode in biological tissue. We show that the electrode axis can be found through maximizing the parallel integral projection transform that is a form of the Radon transform. To accelerate this step, hierarchical mesh-grid algorithm is implemented. Once the axis position is known, localization of the electrode tip is performed. The method was tested on simulated images, on ultrasound images of a tissue mimicking phantom containing a metallic electrode, and on real ultrasound images from breast biopsy. The results indicate that the algorithm is robust with respect to variations in electrode position and speckle noise. Localization accuracy is of the order of hundreds of micrometers and is comparable to the ultrasound system axial resolution.

Experimental three dimensional strain estimation from ultrasonic sectorial data

Most of the studies devoted to elastography are focused on the estimation of the axial component of the strain. However when subjected to any load, whatever the direction, soft biological media deform in the three spatial dimensions. The aim of our work is to build a three dimensional strain mapping from data acquired with a 3D clinical sectorial probe. The estimation of radial strain is based on the estimation of local scaling factors. A method of cross-correlation of interpolated signals between adjacent radiofrequency lines was used to estimate the angular displacement and strain. For the sectorial strain estimation, the same displacement estimation technique has been implemented. The method has been tested on experimental data acquired on calibrated phantoms and compared to simulation.