Radioactive Waste Repository Authority

​In order to place experiments in real geological conditions, a new section of the already active generic underground research facility Bukov (Bukovská et al. 2019) is recently being constructed. It is located in the central Bohemian Massif, in former uranium mine Rožná, at c. 550 m below the surface. During the excavation of new tunnels and laboratory chambers, a complex of geomechanical, structural, geological, hydrogeological and geophysical measurements and monitoring activities is continuously performed. The main objectives of this in-situ characterization project are to understand and 3D visualize the structural record and its hydrogeological systematics. Other objectives are to determine the excavation damage zones, the effect of blasting, the physical and mechanical properties of the rocks, and testing the excavation and drilling methodology. The laboratory is situated mostly in the intensively deformed paragneiss, high-grade amphibolites and migmatites, typical for the European Variscan belt. Geological observations have revealed a complex polyphase deformational pattern of metamorphic foliations, strongly influencing the superposed fault and fracture systems, hydrogeological conditions and rock mass properties. Based on multidisciplinary research of borehole and tunnel data, possible problematical geological structures are identified and investigated. Finally, all obtained data and experience will serve to development of work-flows of documentation and rock-mass suitability classification system during building of the future real deep geological repository. The construction will be completed in 2024 and the underground research facility will become part of the national planning and siting strategy for the deep underground repository for high-level radioactive waste. The data from this research will contribute to the understanding of the geology of the region and will be used for experiments addressing long-term safety and technical feasibility. Such results from the depth can allow correlation and validation of data collected from surface research (Soejono et al. 2021) in the potential sites for deep geological repository construction.  Bukovská, Z., Soejono, I., Vondrovic, L., et al., 2019. Characterization and 3D visualization of underground research facility for deep geological repository experiments: A case study of underground research facility Bukov. Czech Republic. Eng. Geol. 259, 105186. https://doi.org/10.1016/j.enggeo.2019.105186 Soejono, I., Bukovská, Z., Levá, B., et al., 2021. Interdisciplinary geoscientific approach to radioactive waste repository site selection: the Březový potok site, southwestern Czech Republic. J. Maps 17, 741–749. https://doi.org/10.1080/17445647.2021.2004942

Activities involving the use of animals in research date back to more than 2,000 years BCE.At the time, animals were used in surgeries and comparative studies aimed at elucidating the mysteries surrounding the functioning of living organisms.Over the centuries, use has become more frequent, with the improvement of the techniques used, but still without any concern for animal suffering, well-being, or ethical issues.It was only around the 19th century, in England, that questions about this began to arise.Since then, animal protection bodies have been created, laws have been enacted and, in 1959, Russell and Burch created the principle of the 3Rs (replacement, reduction, and refinement), assumptions that guide teaching and research activities involving animals to this day.Recent data show that the number of animals used in research reached 192.1 million in 2015 worldwide, a number that, in 2005, was approximately 127 million.The present work aims to describe the historical evolution of the use of animals in research activities around the world and the protection mechanisms involved so that, from this, we can understand how we evolved to the significant number of scientific productions involving animals today.

Stable iodine isotopes are essential for humans as they are necessary for producing thyroid gland hormones. However, there are hazardous radioactive iodine isotopes that are emitted into the environment through radioactive waste generated by nuclear power plants, nuclear weapon tests, and medical practice. Due to the biophilic character of iodine radionuclides and their enormous biomagnification potential, their elimination from contaminated environments is essential to prevent the spread of radioactive pollution in ecosystems. Since microorganisms play a vital role in controlling iodine cycling and fate in the environment, they also can be efficiently utilized in solving the issue of contamination spread. Thus, this paper summarizes all known on microbial processes that are involved in iodine transformation to highlight their prospects in remediation of the sites contaminated with radioactive iodine isotopes.

Selenium can be highly toxic in excess for both animals and humans. However, since its mobile forms can be easily adsorbed with ferric minerals, its mobility in the natural oxic environment is generally not an issue. Still, the removal and immobilization of the long-lived radioactive isotope 79Se from the contaminated anoxic waters is currently a significant concern. 79Se can be accessible in the case of radionuclides' leaching from radioactive waste disposals, where anoxic conditions prevail and where ferrous ions and Fe(II)-bearing minerals predominate after corrosion processes (e.g., magnetite). Therefore, reductive and adsorptive immobilizations by Fe(II)-bearing minerals are the primary mechanisms for removing redox-sensitive selenium. Even though the information on the sorptive interactions of selenium and Fe(II)-bearing minerals seems to be well documented, this review focuses specifically on the state of the available information on the effects of the redox properties of Fe(II)-bearing solid phases (e.g., ferrous oxides, hydroxides, sulfides, and carbonates) on selenium speciation via redox transformation and co-occurring coprecipitation.

Abstract. Enduring and extensive heavy precipitation events associated with widespread river floods are among the main natural hazards affecting central Europe. Since such events are characterized by long return periods, it is difficult to adequately quantify their frequency and intensity solely based on the available observations of precipitation. Furthermore, long-term observations are rare, not homogeneous in space and time, and thus not suitable to running hydrological models (HMs) with respect to extremes. To overcome this issue, we make use of the recently introduced LAERTES-EU (LArge Ensemble of Regional climaTe modEl Simulations for EUrope) data set, which is an ensemble of regional climate model simulations providing over 12 000 simulated years. LAERTES-EU is adapted for use in an HM to calculate discharges for large river basins by applying quantile mapping with a parameterized gamma distribution to correct the mainly positive bias in model precipitation. The Rhine basin serves as a pilot area for calibration and validation. The results show clear improvements in the representation of both precipitation (e.g., annual cycle and intensity distributions) and simulated discharges by the HM after the bias correction. Furthermore, the large size of LAERTES-EU also improves the statistical representativeness for high return values above 100 years of discharges. We conclude that the bias-corrected LAERTES-EU data set is generally suitable for hydrological applications and posterior risk analyses. The results of this pilot study will soon be applied to several large river basins in central Europe.

This article presents a method for assessing the radionuclide surface contamination density (SCD) on open sites and in premises of a radiation hazardous facility based on measurements of the ambient dose equivalent rate (ADER). The method is intended for use at the initial stage of the assessment of the radiation environment at facilities. The assessed SCD at a given location on the surface can differ from the directly measured SCD at that location, since sources located on the surface and distributed by the depth contribute to the ADER value. The method makes it possible to estimate SCD with reasonable accuracy without increasing the number of measurements, and thus avoid additional occupational exposure and the use of additional resources. SCD and ADER as spatial variables have different support of measurement data. For ADER, measured at a height of 1 m, the support of measurement data can be taken to be a circle in the centre of which a gamma-ray detector is located, with a radius of several tens of meters. In contrast, SCD has the support of measurement data, close to the overall dimensions of the beta detector (100 cm2). To solve the problem of SCD calculation on the basis of ADER measurements, the method of conversion coefficients (MCC) is usually applied, based on the use of conversion factors; however, this method provides an adequate estimate only under conditions of an SCD with low gradient over the surface. The method proposed in this article is applicable for an arbitrary distribution of SCD, and designed to deal with heterogeneous contamination patterns. The developed method is based on the numerical solution of the Fredholm equation of the first kind. The measurement data always contain an error, therefore, the task of the SCD calculation is an ill-posed problem, and the Tikhonov regularisation method (ridge regression) was used to solve it. The article presents the method developed and examples of use. Validation of the method was performed using 38 measurements of the radioactive contamination from 137Cs in soil. It is shown that the method proposed in the article demonstrates a significant superiority in comparison with the MCC method, because it allows more accurate localisation of areas contaminated with radionuclides and is applicable for an arbitrary distribution of SCD.

Este artigo pretende desenvolver uma reflexão sobre os estudos ante­cipatórios e as metodologias de prospecção de futuro e sua relação com a moda, pensada aqui como meio de expressão de comportamentos e de consumo. Essas metodologias são: a análise de tendências, a construção de cenários e a criação de narrativas. Como parte introdutória desta discussão também analisaremos a relação da moda com o tempo, discutindo as possibilidades de se pensar uma moda do futuro.

This study analyzed ninety Chemistry video lessons available on youtube.com.br site during the period of one year, in order to quantify the use of context in these classes. Furthermore, it was also made a classification of the observed contexts based on Kato and Kawasaki (2011) and Smith et al. (2010). For the selection of videos, videos that were analyzed showed up ten thousand views, since it consists of an indication of the use of this resource by students. After the analysis it was established a superficial use of contextualization as a teaching strategy, and it was observed that there is a field of traditional teaching approach, with definitions of concepts and / or phenomena, using examples and problem solving.