Search Results

1 - 2 of 2 items

  • Author: S. Issa x
Clear All Modify Search
Detection and elimination of signal errors due to unintentional movements in biomedical magnetic induction tomography spectroscopy (MITS)

Abstract

In biomedical MITS, slight unintentional movements of the patient during measurement can contaminate the aimed images to a great extent. This study deals with measurement optimization in biomedical MITS through the detection of these unpredictable movements during measurement and the elimination of the resulting movement artefacts in the images to be reconstructed after measurement. The proposed detection and elimination (D&E) methodology requires marking the surface of the object under investigation with specific electromagnetically perturbing markers during multi-frame measurements. In addition to the active marker concept already published, a new much simpler passive marker concept is presented. Besides the biological signal caused by the object, the markers will perturb the primary magnetic field inducing their own signals. The markers' signals will be used for the detection of any unwanted object movements and the signal frames corrupted thereby. The corrupted signal frames will be then excluded from image reconstruction in order to prevent any movement artefacts from being imaged with the object. In order to assess the feasibility of the developed D&E technique, different experiments followed by image reconstruction and quantitative analysis were performed. Hereof, target movements were provoked during multifrequency, multiframe measurements in the β-dispersion frequency range on a saline phantom of physiological conductivity. The phantom was marked during measurement with either a small single-turn coil, an active marker, or a small soft-ferrite plate, a passive marker. After measurement, the erroneous phantom signals were corrected according to the suggested D&E strategy, and images of the phantom before and after correction were reconstructed. The corrected signals and images were then compared to the erroneous ones on the one hand, and to other true ones gained from reference measurements wherein no target movements were provoked on the other hand. The obtained qualitative and quantitative measurement and image reconstruction results showed that the erroneous phantom signals could be accurately corrected, and the movement artefacts could be totally eliminated, verifying the applicability of the novel D&E technique in measurement optimization in biomedical MITS and supporting the proposed aspects.

Open access
Effects of a Single Intramuscular Injection of Vitamin K on the Hematology, Serum Biochemistry and Coagulation Parameters in Healthy Adult Dairy Cows

Abstract

Vitamin K1 is commonly administered to dairy cattle suffering from uncontrollable hemorrhage and to cattle with known deficiency of vitamin K dependent coagulation factors. However, a review of recent literature concludes the absence of available information regarding the safety and effects of this drug in dairy cattle. Therefore, this study was carried out to evaluate the safety and effects of a single intramuscular injection of vitamin K1 (2.5 mg/kg) on various clinical, hematological, serum biochemical and coagulation parameters in adult Holstein dairy cows. Six adult Holstein dairy cows were injected a single intramuscular dose of vitamin K1. Cows were then clinically monitored for 24 hours after drug administration for any abnormal behavioral activities. The heart rate, respiration rate, rectal temperature, and rumen motility were also reported before and at each follow-up check point after administration of the drug. Whole blood samples were collected before and again at 15, 30, 60, and 120 minutes and at 24 hours after drug administration. Hematology and serum biochemistry parameters were evaluated to detect any systemic effects. Selected coagulation parameters including the activated partial thromboplastine time (APTT), prothrombin time (PT), thrombin time (TT), D-dimers, platelets count, and fibrinogen concentrations were determined to evaluate the effect of the drug on coagulation mechanisms. There were no abnormal clinical, pathological, or behavioral activities associated with the drug administration in all cows. In the coagulation profile, there was a significant increase in platelets counts starting from 15 minutes after administration and throughout the observation period. Other coagulation parameters were not significantly changed.

Open access