scholarly journals Study of Multi-Pixel Scintillator Detector Configurations for Measuring Polarized Gamma Radiation

2021 ◽  
Vol 6 (4) ◽  
pp. 43
Author(s):  
Ana Marija Kožuljević ◽  
Damir Bosnar ◽  
Zdenka Kuncic ◽  
Mihael Makek ◽  
Siddharth Parashari ◽  
...  
Keyword(s):  
Compton Scattering ◽  
Gamma Ray ◽  
Azimuthal Angle ◽  
Scattered Photon ◽  
Pixel Detector ◽  
Additional Tool ◽  
Positron Emission ◽  
Set Up ◽  
The One ◽  
Detector Configurations

When a positron annihilates, two gamma photons are created with orthogonal polarizations. It is possible to use coincidence measurements where both photons undergo Compton scattering to estimate their initial relative polarization orientation. This information is of great interest in gamma imaging systems, such as Positron Emission Tomography, where it may be used as an additional tool to distinguish true coincidence events from scatter and random background. The successful utilization of this principle critically depends on the detector’s angular and energy resolution, which determine its polarimetric performance. In this study, we use Monte Carlo simulations based on the Geant4 toolkit to model two multi-pixel detector configurations identified as prospective for the measurement of gamma-ray polarization in PET. One is based on 2 mm × 2 mm × 20 mm LYSO scintillators and the other is based on 3 mm × 3 mm × 20 mm GAGG scintillators. Each configuration has a pair of modules, each consisting of 64 crystals set up in a single 8 × 8 matrix, where both the recoil electron and the Compton-scattered photon are absorbed. We simulate positron annihilation by generating two back-to-back gamma photons of 511 keV with orthogonal polarizations. The Compton scattering is successfully identified and the modulation of the azimuthal angle difference is clearly observed. The configuration based on GAGG crystals demonstrates slightly better polarimetric performance than the one based on LYSO crystals, reflected in the more pronounced azimuthal modulation.

scholarly journals The Swiss National Park

Oryx ◽  
1955 ◽  
Vol 3 (2) ◽  
pp. 64-70
Author(s):  
G. N. Zimmerli
Keyword(s):  
National Park ◽  
Swiss Society ◽  
Large Area ◽  
Nature Protection ◽  
Swiss National Park ◽  
Plant Life ◽  
Eastern Border ◽  
Set Up ◽  
The One ◽  
Protection Commission

The idea of a Swiss national park originated with the Swiss Society for Nature Research and this Society played the leading part in its realization. In 1906 the Society set up as part of its own organization a Swiss Nature Protection Commission and charged it to search for an area in Switzerland suitable for establishment as a reserve, in which all the animal and plant life could be protected against interference by man and so could be left entirely to the play of natural forces. It was not easy to find in Switzerland a suitably large area which still retained its original characteristics, was virtually free from human settlement, and contained some wealth of fauna and flora. After a careful survey of the whole country it became clear that the most suitable region was the Lower Engadine, with its isolated valleys on the eastern border of the country. The district in which, at the beginning of the century, bears had still lived was the one in which primitive nature could be found in its truest state.

scholarly journals Mineral fertilizers as a governing factor of the regulation of the number of fungi in soil

2009 ◽  
pp. 201-207 ◽  
Author(s):  
Marijana Pesakovic ◽  
Dragutin Djukic ◽  
Leka Mandic ◽  
Milan Rakicevic ◽  
Rade Miletic
Keyword(s):  
Soil Fungi ◽  
Mineral Fertilizer ◽  
Mineral Fertilizers ◽  
Nitrogen Rate ◽  
Nutritive Medium ◽  
Governing Factor ◽  
Npk Fertilizer ◽  
Set Up ◽  
The One ◽  
Fertilizer Rates

Over 2003-2005 period, a study was performed on the effect of different rates of NPK fertilizer of formulation 8:16:24 + 3% MgO (N1 - 400 kg ha-1; N2 - 600 kg ha-1; N3 - 800 kg ha-1; N4 - 1000 kg ha-1) on development of the soil fungi. The trial was set up in the experimental plum orchard established by Fruit Research Institute Cacak, and the laboratory of Department of Microbiology, Faculty of Agronomy Cacak. Unfertilized soil was used as the control soil. Each of the stated variants was carried out in three replications. The size of the basic plot was 68 m2. The effect of the studied mineral fertilizer rates was determined three times over the growing season, the number of fungi being checked by the indirect rarefaction method on Chapek nutritive medium. The results of the study inferred that the application of mineral fertilizers brought about the decrease in the number of fungi. Of all studied variants, the one with the highest nitrogen rate (variant N4) exhibited the strongest effect. The influence of the fertilizer was highest at the third sampling. Furthermore, the effect was highest in season 2003.

scholarly journals Improving the performance of 241Am-Be for PGNAA applications using a proper shielding for neutron source and the NaI detector

2010 ◽  
Vol 25 (3) ◽  
pp. 205-211 ◽  
Author(s):  
Hamed Panjeh ◽  
Hashem Hakimabad ◽  
Lalle Motavalli
Keyword(s):  
Gamma Rays ◽  
Energy Region ◽  
Gamma Ray ◽  
Region Of Interest ◽  
High Rate ◽  
Prompt Gamma ◽  
Peak Resolution ◽  
Set Up ◽  
Gamma Ray Detector

The gamma ray spectrum resolution from a 241Am-Be source-based prompt gamma ray activation analysis set-up has been observed to increase in the energy region of interest with enclosing the NaI detector in a proper neutron and gamma ray shield. We have investigated the tact that the peak resolution of prompt gamma rays in the region of interest from the set-up depends on the source activity to the great extent, size and kind of the detector and the geometry of the detector shield. In order to see the role of a detector shield, five kinds of the detector shield were used and finally the proper kind was introduced. Since the detector shield has an important contribution in the reduction of the undesirable and high rate gamma rays coming to the gamma ray detector, a good design of a proper shield enables the elimination of the unwanted events, such as a pulse pile-up. By improving the shielding design, discrete and distinguishable photoelectric peaks in the energy region of interest have been observed in the spectrum of prompt gamma rays.

scholarly journals PLATFORM COOPS NOW!: A team entrepreneurship capacity building program to create platform coops

2021 ◽  
pp. 135-156
Author(s):  
Liher Pillado Arbide ◽  
Ander Etxeberria Aranburu ◽  
Giovanni Tokarski
Keyword(s):  
Capacity Building ◽  
Sharing Economy ◽  
Digital Platforms ◽  
New School ◽  
Digital Era ◽  
The World ◽  
Set Up ◽  
The One ◽  
Building Program ◽  
Capacity Building Program

Traditional labour relationships have been disrupted due to the digital platforms based businesses. This article aims on the one hand to share the consequences the sharing economy has generated for workers, and how MONDRAGON’s principles as one of the best examples of worker owned business group in the world, can be applied within the new digital era. On the other hand, this paper provides a literature review on how digital platforms can operate with fairer principles based on the framework that platform coops consist of. Last but not least, Mondragon University and The New School have set up a capacity building program on team entrepreneurship and an online incubation program that aims to support the creation of platform coops, whose results after two editions and future opportunities for research are shared.

scholarly journals Improving Interior Environmental Quality Using Sustainable Design in Jordanian Hospital Bedrooms

2020 ◽  
Vol 9 (3) ◽  
pp. 443
Author(s):  
Saeed Hussein Alhmoud ◽  
Çiğdem Çağnan ◽  
Enis Faik Arcan
Keyword(s):  
Interior Design ◽  
Environmental Quality ◽  
Sustainable Design ◽  
Health Sector ◽  
Green Building ◽  
Climatic Conditions ◽  
Building Assessment ◽  
The World ◽  
Set Up ◽  
The One

As the wave of sustainability is sweeping across the major countries and cities of the world, the effect of the inevitable change is finding its way through to the health sector as well. Since the main functions of the hospital include healing the patient, it aims to provide adequate health services to people. Hospitals managers should strive to realize facilities that meet a certain level of demand. This study aims to present the interior environmental quality (IEQ) of bedrooms in Jordanian hospitals and propose a solution to improve indoor environment quality using sustainable design principles. A qualitative research methodology is used in this study. A comparative analysis is made between the original set up of the hospital buildings and the present conditions in which they are in. During the research, it was found that the design to be applied for a hospital should be following the healing environmental characteristics. Besides, the design of hospitals should be made with the climatic conditions of the area in mind. In the advanced countries of the world, hospitals are generally built with extensive research and important factors such as temperature, wind direction and humidity are taken into consideration. The design for a hospital building should be assessed according to the German Green Building Assessment (DGNB) criteria. It has been found that the one-bedroom is ideal for patients because it provides the necessary privacy and also greatly reduces the spread of the disease. In hygienic practices, there should be a first-class healing environment with evidence-based medical research. It was concluded that the practices involving the use of sustainable designs can be followed with the hints received from hospitals in the advanced countries of the world. Keywords: Jordan hospital; IEQ; bedroom; interior design; healthcare; green building assessment; DGNB

scholarly journals 4 The Court and Domestic and International Legal Systems

2020 ◽  
Author(s):  
Nussberger Angelika
Keyword(s):  
Human Rights ◽  
European Convention ◽  
Vienna Convention ◽  
Legal Systems ◽  
Member States ◽  
Supreme Courts ◽  
European Court ◽  
Set Up ◽  
The One ◽  
The Relationship

This chapter assesses the relationship between the European Court of Human Rights (ECtHR) and domestic and international legal systems. With the ratification of the European Convention on Human Rights (ECHR), the Member States accept to be bound by final judgments of the Court and to implement them in their domestic legal systems. The Convention system does not make any difference as to the set-up of the national legal system or to the hierarchical position accorded to the Convention in national law. This is in line with a purist international law perspective, summarized in Article 27 of the Vienna Convention of the Law on Treaties: ‘A party may not invoke the provisions of its internal law as justification for its failure to perform a treaty.’ However, from the constitutional law perspective of the Member States, the situation is much more multi-faceted and complex. While it is generally accepted that the Court's judgments are binding and have to be implemented, the relationship between the Convention and the national constitutions as well as between their respective guardians, the Court on the one hand and national constitutional or supreme courts on the other hand, is not seen as one-way and hierarchical, but nuanced and differentiated. Implementation of judgments is accepted to be a duty, but not necessarily without exceptions. The chapter then considers the relationship between the ECtHR and the European Court of Justice (ECJ).

scholarly journals Changes And New Constraints In The Competition Rules Enforcement Due To Accession: The Perception Of The Romanian Companies

2011 ◽  
Vol 7 (4) ◽  
Author(s):  
Alina Mihaela Dima
Keyword(s):  
Competition Policy ◽  
Negative Impact ◽  
Free Market ◽  
National Level ◽  
Well Being ◽  
Business Environment ◽  
Competition Rules ◽  
Set Up ◽  
The One ◽  
The Right

Many times, in the attempt to win or to maintain an advantageous position on the market, the economic agent will use a whole arsenal of practices (inclusively and mostly from the marketing field), most of them anticompetitive, with a negative impact on the business environment, which also affects the well-being of the consumer. The policy in the field of competition is the one that defines these types of behaviour and penalizes them depending on the importance of their negative impact, by creating a complex and coherent legislative and institutional mechanism. The right enforcement of the competition policy at the national level is the key in this process, but this should be coordinated with the regional and international objectives and regulations in this field. Romania is facing a double challenge: on the one side, it had to set up a competition policy, which was almost ignored before the90s, on the other side, it had to comply, recently, with high standards in the field, as an EU candidate. Now, as a member state, the promotion of a competition culture becomes a must, along with the design of an adequate system of information and knowledge dissemination for all of those involved. The paper is based on a original and qualitative research and aims at emphasising the increased necessity of the promotion of a competition culture for the competitiveness of the Romanian business environment on the European level in the new context of accession. This will help Romanian business to face the competition challenges within a more extended single European market, as an essential issue of the free market economy status recently granted, and accordingly to the most important EU objectives set up at Lisabon to become the most competitive economy in the world up to 2010.

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