Thyroglobulin (Tg) is a glycoprotein produced exclusively by the thyroid. It can be found in the serum of healthy people as well as of those with various thyroid disorders. Elimination of Tg from the ...body occurs through the liver. The data on Tg serum half-life in the literature are scarce, and the reported values vary from 6–96 h. The aim of our study was to determine the Tg half-life after surgical removal of the thyroid gland. Knowing the exact half-life of Tg would enable rational timing of sampling serum for determination of Tg after thyroid surgery or chemotherapy and/or irradiation for evaluation of treatment in patients with differentiated thyroid cancer (DTC). In 11 patients (10 females and one male, aged 27–85 years) serum samples were taken 24, 48, 72 and 168 h after a near-total or total thyroidectomy. Serum Tg levels were determined and Tg half-life calculated by the use of a one-compartment kinetic model. Mean Tg half-life was 65.2 h (SEM=4.3), and Tg levels decrease below 5–10 ng/ml approximately only 25 days after thyroidectomy (7–10 × t(7−10 x
t
1/2). Therefore, earlier determination of Tg cannot be used either for reliable detection of distant metastases or for evaluation of the effect of chemotherapy and/or irradiation.
This research demonstrates the basic elements of a prototype automated orchard sprayer which delivers pesticide spray selectively with respect to the characteristics of the targets. The density of an ...apple tree canopy was detected by PROWAVE 400EP250 ultrasound sensors controlled by a Cypress PSOC CY8C29466 microcontroller. The ultrasound signal was processed with an embedded computer built around a LPC1343 microcontroller and fed in real time to electro-magnetic valves which open/close spraying nozzles in relation to the canopy structure. The analysis focuses on the detection of appropriate thresholds on 15 cm ultrasound bands, which correspond to maximal response to tree density, and this was selected for accurate spraying guidance. Evaluation of the system was performed in an apple orchard by detecting deposits of tartrazine dye (TD) on apple leaves. The employment of programmable microcontrollers and electro-magnetic valves decreased the amount of spray delivered by up to 48.15%. In contrast, the reduction of TD was only up to 37.7% at some positions within the tree crown and 65.1% in the gaps between trees. For all these reasons, this concept of precise orchard spraying can contribute to a reduction of costs and environmental pollution, while obtaining similar or even better leaf deposits.
Ultrasonic cavitation was generated with ultrasound of 33 kHz in a small closed water tank, containing about one liter of water. Cavitation was experimentally observed simultaneously with high-speed ...cameras in IR and visible spectra. Cameras were capturing images of the same observation area. From the images obtained time-dependent velocity fields were calculated for both cameras. Velocity calculation was based on pattern and similitude recognition between pairs of consecutive images. Images from the visible spectrum were also processed in order to detect the individual graphical objects presumably linked with cavitation collapses. As a result, correlations between velocity fields from each camera and correlations between velocity fields and cavitation collapses were determined. Strong correlations were found in all cases. Additionally, a delay was found for the velocities from the camera in the visible spectrum when compared to the thermographic results. Also the behavior of the correlation between cavitation collapses and velocities was in some cases found to be dependent on whether the velocities were from the images taken in the visible or the IR spectrum. Keywords: cavitation, ultrasound, IR thermography, velocity fields, correlation, bubble collapse, visualization. 1 Introduction Ultrasonic cavitation has many applications (Mason and Lorimer 1, Brennen 2) and an obvious question that arises when one is dealing with it, is what is happening inside. In search for a non-trivial answer, an experimental approach to measure basic flow quantities seems appropriate, since currently available
The Pelton turbines are the part of the pump-storage scheme that is working under permanent backpressure conditions. The knowledge of air-absorbing and degassing in the vessel which follows the ...turbine chamber is important for the safe and economical working of the turbine. In the case of so called hydraulic short circuit the influence of air bubbles for the safe operation of turbines and pumps is very important. To estimate the volume void fraction in two-phase flow, the measurement method was developed, which is based on the computer-aided visualization. Acquisition of flow images by a fast video camera followed by the computer processing of the acquired images enables the determination of the void fraction via the average value of grey level intensity of the acquired flow images. A relationship between the void fracture and the average grey level intensity was obtained through calibration of the measurement system. Simultaneous measurements with the other measurement method revealed suitability and applicability of the visualization method in a real industrial environment such as a tailwater channel of a Pelton turbine. Apart from that, a study revealed that by further processing the images a number of other important information on the flow, such as bubble size and shape, average bubble direction and velocity, can be obtained by the described method.
The aim of this study was to evaluate the ability of axillary ultrasound (US) and US-guided fine-needle aspiration biopsy (FNAB) to detect axillary LN metastases. Between January 2001 and September ...2003, axillary US was performed in 165 patients with cytologically or histologically proven breast cancer and clinically non-palpable axillary LNs. In patients with US suspicious LNs, US-guided FNAB was performed and patients with cytologically proven malignant LNs proceeded directly to the ALND. In 49/90 patients with US suspicious LNs, US-guided FNAB was performed. It was positive in 33/49 patients. Definitive histology report revealed LN metastases in 65/165 patients. The sensitivity, specificity, positive and negative predictive value of the US-FNAB, were 84, 91, 97 and 62%. Axillary US in a combination with US-FNAB is a valuable method in preoperative staging of patients with breast cancer. Almost 50% of patients with LN metastases can be spared the second operation. However, it is very much operator-dependent and equipment-dependent.
A novel method of measurement and control of the primary layer quality in mineral wool production processes is presented. The measurement method is based on image acquisition and processing of the ...mineral wool primary layer structure. As a statistical estimator of the primary layer quality, the ratio between the RMS (root mean square) and the average intensity in a selected region of the image was used. A regression model of mineral wool production process control is presented. It relates the statistical estimator of the primary layer homogeneity with the key process parameters. The regression model was derived using dimensional analysis and selection of characteristic numbers. The parameters of the regression model were selected using experimental data from a spinning machine. The results show very good agreement with a regression coefficient r
2
higher than 0.81. The regression model permits mineral wool production process control, since all the key parameters in the model can be measured in a real production process.
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