37 research outputs found

    Commercial P-Channel Power VDMOSFET as X-ray Dosimeter

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    This research was funded by the European Union's Horizon 2020 research and innovation programme under grant agreement No. 857558, and the Ministry of Education, Science, and Technological Development of the Republic of Serbia under the project No. 43011.The possibility of using commercial p-channel power vertical double-diffused metal-oxidesemiconductor field-effect transistors (VDMOSFETs) as X-ray sensors is investigated in this case study. In this aspect, the dependence of sensitivity on both the gate voltage and the mean energy for three X-ray beams is examined. The eight gate voltages from 0 to 21 V are applied, and the dependence of the sensitivity on the gate voltage is well fitted using the proposed equation. Regarding X-ray energy, the sensitivity first increases and then decreases as a consequence of the behavior of the mass energy-absorption coefficients and is the largest for RQR8 beam. As the mass energy-absorption coefficients of SiO2 are not found in the literature, the mass energy-absorption coefficients of silicon are used. The behavior of irradiated transistors during annealing at room temperature without gate polarization is also considered.European Commission 857558Ministry of Education, Science & Technological Development, Serbia 4301

    Radiation sensitive MOSFETs irradiated with various positive gate biases

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    This work was supported in part by the European Union's Horizon 2020 research and innovation programme under grant agreement No. 857558, and the Ministry of Education, Science and Technological Development of the Republic of Serbia, under the project No. 43011.The RADiation sensitive metal-oxide-semiconductor field-effect-transistors (RADFETs) were irradiated with gamma rays up to absorbed dose of 110 Gy(H2O). The results of threshold voltage, V-T , during irradiation with various positive gate biases showed the increase in V-T with gate bias. The threshold voltage shift, Delta V-T , during irradiation was fitted very well. The contributions of both the fixed traps (FTs) and switching traps (STs) during radiation on Delta V-T were analyzed. The results show the significantly higher contribution of FTs than STs. A function that describes the dependence of threshold voltage shift and its components on gate bias was proposed, which fitted the experimental values very well. The annealing at the room temperature without gate bias of irradiated RADFETs was investigated. The recovery of threshold voltage, known as fading, slightly increase with the gate bias applied during radiation. The Delta V-T shows the same changes as the threshold voltage component due to fixed states, Delta V-ft , while there is no change in the threshold voltage component due to switching traps, Delta V-st .European Union's Horizon 2020 research and innovation programme 857558Ministry of Education, Science & Technological Development, Serbia 4301

    Plasma lipid profiles discriminate bacterial from viral infection in febrile children

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    Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection are often non-specific, and there is no definitive test for the accurate diagnosis of infection. The 'omics' approaches to identifying biomarkers from the host-response to bacterial infection are promising. In this study, lipidomic analysis was carried out with plasma samples obtained from febrile children with confirmed bacterial infection (n = 20) and confirmed viral infection (n = 20). We show for the first time that bacterial and viral infection produces distinct profile in the host lipidome. Some species of glycerophosphoinositol, sphingomyelin, lysophosphatidylcholine and cholesterol sulfate were higher in the confirmed virus infected group, while some species of fatty acids, glycerophosphocholine, glycerophosphoserine, lactosylceramide and bilirubin were lower in the confirmed virus infected group when compared with confirmed bacterial infected group. A combination of three lipids achieved an area under the receiver operating characteristic (ROC) curve of 0.911 (95% CI 0.81 to 0.98). This pilot study demonstrates the potential of metabolic biomarkers to assist clinicians in distinguishing bacterial from viral infection in febrile children, to facilitate effective clinical management and to the limit inappropriate use of antibiotics

    Plasma lipid profiles discriminate bacterial from viral infection in febrile children

    Get PDF
    Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection ar

    Plasma lipid profiles discriminate bacterial from viral infection in febrile children

    Get PDF
    Fever is the most common reason that children present to Emergency Departments. Clinical signs and symptoms suggestive of bacterial infection are often non-specific, and there is no definitive test for the accurate diagnosis of infection. The 'omics' approaches to identifying biomarkers from the host-response to bacterial infection are promising. In this study, lipidomic analysis was carried out with plasma samples obtained from febrile children with confirmed bacterial infection (n = 20) and confirmed viral infection (n = 20). We show for the first time that bacterial and viral infection produces distinct profile in the host lipidome. Some species of glycerophosphoinositol, sphingomyelin, lysophosphatidylcholine and cholesterol sulfate were higher in the confirmed virus infected group, while some species of fatty acids, glycerophosphocholine, glycerophosphoserine, lactosylceramide and bilirubin were lower in the confirmed virus infected group when compared with confirmed bacterial infected group. A combination of three lipids achieved an area under the receiver operating characteristic (ROC) curve of 0.911 (95% CI 0.81 to 0.98). This pilot study demonstrates the potential of metabolic biomarkers to assist clinicians in distinguishing bacterial from viral infection in febrile children, to facilitate effective clinical management and to the limit inappropriate use of antibiotics

    Radiation and Spontaneous Annealing of Radiation-sensitive Field-effect Transistors with Gate Oxide Thicknesses of 400 and 1000 nm

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    This work was supported in part by the European Union's Horizon 2020 research and innovation programme (Grant No. 857558) and the Ministry of Education, Science and Technology Development of the Republic of Serbia (Project No. 43011).We investigated the influence of gamma radiation of 50 Gy(H2O) on radiation-sensitive p-channel metal-oxide-semiconductor field-effect transistors with an Al gate (RADFETs) with gate oxide thicknesses of 400 and 1000 nm and gate voltages of 0 and 5 V. The obtained results showed that the sensitivity S at a given gate voltage increases with the square of the gate oxide thickness. After irradiation (IR), spontaneous annealing (SA) was performed at room temperature without voltage at the gate. We present the behaviors of fixed traps and switching traps, determined by the midgap technique, and that of fast switching traps, determined by the charge-pumping technique, during IR and SA. A very important characteristic of dosimetric transistors is fading, which represents the recovery of the threshold voltage of the irradiated RADFETs during SA. The maximum fading is about 15% after 9100 h, except for the RADFETs with a gate oxide thickness of 1000 nm and a gate voltage of 5 V, for which it is about 30%. A fitting equation for fading was proposed, which fitted the experimental fading values very well.European Union's Horizon 2020 research and innovation programme 857558Ministry of Education, Science & Technological Development, Serbia 4301

    Sensitivity and fading of irradiated RADFETs with different gate voltages

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    This work was supported in part by the European Union's Horizon 2020 research and innovation programme under grant agreement No. 857558, and the Ministry of Education, Science and Technological Development of the Republic of Serbia, under the project No. 43011.The radiation-sensitive field-effect transistors (RADFETs) with an oxide thickness of 400 nm are irradiated with gate voltages of 2, 4 and 6 V, and without gate voltage. A detailed analysis of the mechanisms responsible for the creation of traps during irradiation is performed. The creation of the traps in the oxide, near and at the silicon/silicon-dioxide (Si/SiO2) interface during irradiation is modelled very well. This modelling can also be used for other MOS transistors containing SiO2. The behaviour of radiation traps during postirradiation annealing is analysed, and the corresponding functions for their modelling are obtained. The switching traps (STs) do not have significant influence on threshold voltage shift, and two radiation-induced trap types fit the fixed traps (FTs) very well. The fading does not depend on the positive gate voltage applied during irradiation, but it is twice lower in case there is no gate voltage. A new dosimetric parameter, called the Golden Ratio (GR), is proposed, which represents the ratio between the threshold voltage shift after irradiation and fading after spontaneous annealing. This parameter can be useful for comparing MOS dosimeters.European Commission 857558Ministry of Education, Science & Technological Development, Serbia 4301

    The sensitivity of 100 nm RADFETs with zero gate bias up to dose of 230 Gy(Si)

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    The RADFETs (pMOS dosimeters) were irradiated by ionizing radiation from Co-60 gamma-ray source to dose of 230 Gy(Si) without gate bias, and their reproducibility and sensitivity to radiation were investigated. The completely automatic system containing switching matrix have been used, enabling very reliable measurements of RADFET electrical characteristics. Two sample types from each RADFET chip, with the same gate oxide thickness, but different geometry (channel width and length), were investigated. The samples have shown good reproducibility of the threshold voltage shift during irradiation, i.e., the radiation sensitivity was similar for all samples. Using MG and CP techniques, it has been shown that the slow switching (border) trap density is negligible, but the fixed trap density saturates and the fast switching trap density is linear. (C) 2011 Elsevier B.V. All rights reserved

    Bridging the gap between informatics and medicine upon medical school entry: Implementing a course on the Applicative Use of ICT

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    <div><p>Education is undergoing profound changes due to permanent technological innovations. This paper reports the results of a pilot study aimed at developing, implementing and evaluating the course, "Applicative Use of Information and Communication Technologies (ICT) in Medicine," upon medical school entry. The Faculty of Medicine, University of Belgrade, introduced a curriculum reform in 2014 that included the implementation of the course, “Applicative Use of ICT in Medicine” for first year medical students. The course was designed using a blended learning format to introduce the concepts of Web-based learning environments. Data regarding student knowledge, use and attitudes towards ICT were prospectively collected for the classes of 2015/16 and 2016/17. The teaching approach was supported by multimedia didactic materials using Moodle LMS. The overall quality of the course was also assessed. The five level Likert scale was used to measure attitudes related to ICT. In total, 1110 students were assessed upon medical school entry. A small number of students (19%) had previous experience with e-learning. Students were largely in agreement that informatics is needed in medical education, and that it is also useful for doctors (4.1±1.0 and 4.1±0.9, respectively). Ability in informatics and use of the Internet in education in the adjusted multivariate regression model were significantly associated with positive student attitudes toward ICT. More than 80% of students stated that they had learned to evaluate medical information and would use the Internet to search medical literature as an additional source for education. The majority of students (77%) agreed that a blended learning approach facilitates access to learning materials and enables time independent learning (72%). Implementing the blended learning course, "Applicative Use of ICT in Medicine," may bridge the gap between medicine and informatics upon medical school entry. Students displayed positive attitudes towards using ICT and gained adequate skills necessary to function effectively in an information-rich environment.</p></div
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