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A 34-year-old Sri Lankan man presented with multiple episodes of vomiting following accidental ingestion of 100 ml of indoxacarb (Avaunt). He had a significant saturation gap (discrepancy between oxygen saturation [98%] in blood gas analysis and saturation on pulse oximetry [70%] in finger pulse oximetry), the color of the blood was muddy brown, and the methemoglobin level (60%) was high in the blood gas analysis. A diagnosis of methemoglobinemia secondary to indoxacarb poisoning was made, and he was treated with methylene blue with a favorable outcome. Methemoglobinemia secondary to indoxacarb poisoning is extremely rare, and clinicians should be aware of this important complication. Methemoglobinemia secondary to indoxacarb poisoning has a favorable outcome if recognized and treated promptly. [ABSTRACT FROM AUTHOR]

In this work we present for the first time an approach for identifying the geometric and material characteristics of layered composite structures through an inverse wave and finite element approach. More specifically, this Non-Destructive Evaluation (NDE) approach is able to recover the thickness, density, as well as all independent mechanical characteristics such as the tensile and shear moduli for each layer of the composite structure under investigation. This is achieved through multi-frequency single shot measurements. It is emphasized that the success of the approach is independent of the employed excitation frequency regime, meaning that both structural dynamics and ultrasound frequency spectra can be employed. It is demonstrated that more efficient convergence of the identification process is attained closer to the bending-to-shear transition range of the layered structure. Since a full FE description is employed for the periodic composite, the presented approach is able to account for structures of arbitrary complexity. The procedure is applied to a sandwich panel with composite facesheets and results are compared with two wave-based characterization techniques: the Inhomogeneous Wave Correlation method and the Transition Frequency Characterization method. Numerical simulations and experimental results are presented to verify the robustness of the proposed method.

The increased use of composite materials in modern aerospace and automotive structures, and the broad range of launch vehicles’ operating temperature imply a great temperature range for which the structures has to be frequently and thoroughly inspected. A thermal mechanical analysis is used to experimentally measure the temperature-dependent mechanical properties of a composite layered panel in the range of -100°C to 150°C. A hybrid wave finite element/finite element computational scheme is developed to calculate the temperature-dependent wave propagation and interaction properties of a system of two structural waveguides connected through a coupling joint. Calculations are made using the measured thermomechanical properties. Temperaturedependent wave propagation constants of each structural waveguide are obtained by the wave finite element approach and then coupled to the fully finite element described coupling joint, on which damage is modelled, in order to calculate the scattering magnitudes of the waves interaction with damage across the coupling joint. The significance of the panel’s glass transition range on the measured and calculated properties is emphasised. Numerical results are presented as illustration of the work.

Synthesis of novel symmetrical azoxy diesters have been prepared by the reaction of 4,4'-dihydroxyazoxy benzene with aliphatic acid halides of varying chain lengths. The synthesized compounds have been characterized by spectral and analytical data. These symmetrical azoxy diesters exhibit good antifungal activity against six fungal strains (Mucor species, Aspergillus niger, Aspergillus flavus, Alternaria solani, Fusarium solani and Aspergillus fumigatus) and antitumor activities while no significant antibacterial activity has been observed. These synthesized compounds are also potent free radical scavengers. [ABSTRACT FROM AUTHOR]