To facilitate progress in climate change adaptation policy and practice, it is important not only to ensure the production of accurate, comprehensive and relevant information, but also the easy, ...timely and affordable access to it. This can contribute to better-informed decisions and improve the design and implementation of adaptation policies and other relevant initiatives. Web-based platforms can play an important role in communicating and distributing data, information and knowledge that become constantly available, reaching out to a large group of potential users. Indeed in the last decade there has been an extensive increase in the number of platforms developed for this purpose in many fields including climate change adaptation. This short paper concentrates on the web-based adaptation platforms developed in Europe. It provides an overview of the recently emerged landscape, examines the basic characteristics of a set of platforms that operate at national, transnational and European level, and discusses some of the key challenges related to their development, maintenance and overall management. Findings presented in this short paper are discussed in greater detailed in the Technical Report of the European Environment Agency Overview of climate change adaptation platforms in Europe.
Single photon emission computed tomography images suffer from low contrast as a result of photon scatter. The standard method for excluding the scatter component in pixelized scintillators is the ...application of an energy window around the central photopeak channel of each crystal cell, but small angle scattered photons still appear in the photopeak window, and they are included in the reconstructed images. A number of scatter correction techniques have been proposed in order to estimate the scatter component, but they have not yet been applied in pixelized scintillators, where most groups use the standard one-photopeak window for scatter correction. In this paper, the author have assessed three subtraction techniques that use a different approach in order to calculate the scatter component and subtract it from the photopeak image: the dual energy window subtraction technique, the convolution subtraction technique, and a deconvolution technique. All these techniques are compared to the standard method
BaSiF
phosphor was synthesized by a gel combustion method. The crystalline size was found to be 54.17 ± 4.36 nm using Williamson-Hall (W-H) approximation. The TL data collected by means of a ...combination of a commercial BG39 and HC575/25 filters was studied to evaluate basic kinetic parameters. Three TL glow peaks of BaSiF
phosphors are centered at around 84, 190 and 322 °C. T
-T
, various heating rate (VHR) and computerized glow-curve deconvolution (CGCD) method were utilized to analyse collected data. Our findings indicate that luminescence process in scrutinized material may obey second order kinetics. The TL dose response of the TL glow peaks exhibits a linear characteristic up to 100 Gy. Deconvolution of the glow curve reveals that the number of the component TL glow peaks in the complex glow curve is composed of well-isolated six overlapping glow peaks. The FOM value is 2.32.
In this study, the thermoluminescence (TL) characteristics of Ag-doped and undoped lithium tetraborate (Li
B
O
, LTB) materials, grown using the Czochralski method, were reported. The TL properties ...of LTB:Ag, such as glow curve structure, dose response, fading and reproducibility, were investigated. The glow curve of the Li
B
O
:Ag single crystal consists of four peaks located at approximately 75, 130, 190 and 275°C; in undoped LTB, the single crystal shows a broad glow curve with peaks at 65, 90, 125, 160 and 190°C using a heating rate of 5°C/s in the 50-350°C temperature region. The high temperature peak of Ag-doped sample at 275°C has a nonlinear dose response within the range from 33 mGy to 9 Gy. There is a linear response in the range of 33-800 mGy; after which, a sublinear region appears up to 9 Gy for Ag-doped LTB single crystal. For undoped single crystal, the dose response is supralinear for low doses and linear for the region between 1 and 9 Gy. The thermal fading ratio of the undoped material is almost 60% for the high temperature peak after 7 days. Ag-doped LTB single crystal exhibits different behaviour over a period of 7 days.
A PMT-Block test bench Adragna, P.; Antonaki, A.; Boudagov, I. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2006, Letnik:
564, Številka:
1
Journal Article
Recenzirano
The front-end electronics of the ATLAS hadronic calorimeter (Tile Cal) is housed in a unit, called
PMT-Block. The PMT-Block is a compact instrument comprising a light mixer, a PMT together with its ...divider and a
3-in-1 card, which provides shaping, amplification and integration for the signals. This instrument needs to be qualified before being assembled on the detector. A PMT-Block test bench has been developed for this purpose. This test bench is a system which allows fast, albeit accurate enough, measurements of the main properties of a complete PMT-Block. The system, both hardware and software, and the protocol used for the PMT-Blocks characterization are described in detail in this report. The results obtained in the test of about 10
000 PMT-Blocks needed for the instrumentation of the ATLAS (LHC-CERN) hadronic Tile Calorimeter are also reported.
Origanum dictamnus (dittany) aerial parts methanol extract was subjected to semi-preparative RP-HPLC fractionation and four novel compounds were identified. The antioxidant capacity of the methanol ...extract and individual fractions were estimated using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) in vitro assay. Methanol extract and the new compounds exhibited significant scavenging activity. Moreover, the antimitotic activities of the methanol extract as well as that of rosmarinic acid were examined and appeared to be several fold weaker comparing to their scavenging capacity. Display omitted
► In this study we analyzed in detail the methanol extract of Origanum dictamnus aerial parts. ► The isolation and structural characterization of 4 new depsides are reported. ► The DPPH scavenging activity of Origanum dictamnus (dittany) methanol extract and new compounds was evaluated.
We herein describe the identification of four new depsides present in methanol extract of Origanum dictamnus. O. dictamnus’ (dittany) aerial parts methanol extract was subjected to semi-preparative RP-HPLC fractionation followed by identification of individual compounds in each fraction using 1D/2D NMR, MS approaches and DFT calculations. The structural data revealed that 4 of the compounds were novel hitherto unidentified molecules, whereas the other 6 corresponded to known structures belonging to the groups of monoterpenes, phenolic acids and depsides. We have additionally estimated the antioxidant capacity of the methanol extract and individual fractions using the 1,1-diphenyl-2-picrylhydrazyl (DPPH) in vitro assay. Methanol extract exhibited significant scavenging activity, which was attributed predominantly to the depside group of phytochemicals. The scavenging activity of the new compounds is reported herein for first time. Moreover, the antimitotic activities of the methanol extract as well as that of rosmarinic acid were examined and appeared to be several fold weaker comparing to their scavenging capacity.
SPECT images suffer from low contrast as a result of photons scatter. The standard method for excluding scatter component in pixelized scintillators is the application of an energy window around the ...central photopeak channel of each crystal cell, but small angle scattered photons still appear in the photopeak window and they are included in the reconstructed images. A number of scatter correction techniques have been proposed in order to estimate the scatter component but they have not yet been applied in pixelized scintillators, where most groups use the standard one-photopeak window for scatter correction. In this work we have assessed three subtraction techniques that use a different approach in order to calculate the scatter component and subtract it from the photopeak image: The dual energy window subtraction technique (DEWST) the convolution subtraction technique (CST) and a deconvolution technique (DT). All these techniques are compared to the standard method
The purpose of this study is to introduce a novel empirical iterative algorithm for medical image reconstruction, under the short name ISWLS (image space weighted least squares), which is expected to ...have image space reconstruction algorithm (ISRA) properties in noise manipulation and weighted least-squares (WLS) acceleration of the reconstruction process. We used phantom data from a prototype small-animal positron emission tomography system and the methods presented here are applied to 2-D sinograms. Further, we assess the performance of the new algorithm by comparing it to the simultaneous version of algebraic reconstruction technique (ART), simultaneous algebraic reconstruction technique (SART), to expectation maximization maximum likelihood (EM-ML), ISRA, and WLS. All algorithms are compared in terms of cross-correlation coefficient, reconstruction time, and contrast-to-noise ratios (CNRs). As it turns out, ISWLS presents higher CNRs than EM-ML, ISRA, and SART for objects of different sizes. Also, ISWLS shows similar performance to WLS during the first iterations but it has better noise manipulation. Finally, ordered subsets ISWLS (OS-ISWLS), the OS version of ISWLS, shows its best performance between the first six-nine iterations. Its behavior seems to be a compromise between OS-ISRA and OS-WLS.
PDF
