Artykuły w czasopismach: „Nuclear Waste Technical Review Board”

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Cantlon, John E. "Nuclear waste management in the US: The Nuclear Waste Technical Review Board's perspective". Nuclear Engineering and Design 176, nr 1-2 (listopad 1997): 111–20. http://dx.doi.org/10.1016/s0029-5493(96)01339-8.

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Fernández-Arias, Pablo, Diego Vergara i Álvaro Antón-Sancho. "Global Review of International Nuclear Waste Management". Energies 16, nr 17 (27.08.2023): 6215. http://dx.doi.org/10.3390/en16176215.

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In the current situation of global energy transition, nuclear energy maintains its reputation as a stable power generation technology, without dependence on other resources and without CO2 emissions. However, one of the main problems with its use is the management of the radioactive waste it generates, which has given rise to different international strategies: (i) reprocessing; (ii) storage; and (iii) disposal. Given the interest generated by nuclear energy in recent times and the need to manage the waste generated, this paper presents a global review of the different international nuclear waste management strategies, using a scientific method based on (i) a bibliometric review of the scientific publications related to nuclear waste management and (ii) an analysis of the technical aspects of the different international management strategies. The effective and safe management of nuclear waste will contribute to the advancement of international nuclear energy development strategies that encourage the construction of new nuclear power plants and the lifetime extension of existing ones.

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Fayek, Mostafa, i Julie Brown. "Natural and Anthropogenic Analogues for High-Level Nuclear Waste Disposal Repositories: A Review". Canadian Mineralogist 59, nr 1 (1.01.2021): 287–317. http://dx.doi.org/10.3749/canmin.2000051.

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ABSTRACT Projects involving deep geological disposal of nuclear waste are unique in that predictive models of long-term safety often involve geological timeframes. This manuscript provides a review of natural and anthropogenic analogues for high-level nuclear waste disposal in a deep geological repository. We also occasionally highlight analogues that have been used for low- and intermediate-level waste. Most studies define natural analogues as either naturally occurring or anthropogenic systems. In this paper, we distinguish between natural analogues and anthropogenic analogues because the latter generally provide non-technical (anecdotal) illustrations of concepts and processes for the safety case, whereas the former can provide technical and quantitative information. In addition, natural analogues can provide information over geological time scales (millions of years) and spatial scales (kilometers), whereas anthropogenic analogues provide information over a much more limited time scale (hundreds or thousands of years). Regardless of the definition, analogue studies provide one of the multiple lines of evidence intended to increase confidence in the safe geological disposal of high-level nuclear waste. They are deemed necessary because they complement the experiments that are carried out over a period of months or years. They also provide a way to validate numerical long-term safety assessment models with information and data covering geological time scales and spatial scales. The first part of this review describes the analogue concept. The second and third parts provide examples of natural and anthropogenic analogues for engineered barrier systems and natural barriers. Part four describes analogues for complex coupled transport processes. Finally, we discuss general and specific areas of future research. A concerted effort should be made to ensure that there is a transfer of data from the complex, natural analogue field studies to simplistic models which, by necessity, are used to evaluate the long-term safety of deep geological repositories. Field analogue studies should be planned to interface with laboratory experiments and, ultimately, with in situ field experiments, when the final repository site is selected. This will involve using natural analogue data in a quantitative way to support the deep geological repository safety case.

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Durant, Darrin. "Resistance to Nuclear Waste Disposal: Credentialed Experts, Public Opposition and their Shared Lines of Critique". Scientia Canadensis 30, nr 1 (30.06.2009): 1–30. http://dx.doi.org/10.7202/800524ar.

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Abstract This article asks the question whether, in regard to controversial technical decision-making, lay public groups advance different kinds of resistance than credentialed experts. This question is explored via a case-study analysis of one of Canada's major public controversies of the past quarter century—nuclear waste disposal. Having arrived on the policy radar in 1977, nuclear waste remained an internal government/nuclear industry matter until terms of reference for a public inquiry were announced in 1989. Several access points for public input followed that announcement: scoping sessions in 1990, comments received during 1994-96 on an Environmental Impact Statement (EIS) prepared by Atomic Energy Canada Limited (AECL), nation-wide public hearings in 1996-97, and ongoing public consultation since 2002. This article focuses on the comments on the EIS, and discusses several lines of shared resistance: the expert judgment of AECL was disputed, the lack of peer review was criticized, accusations of unreliability were made, and general deficiencies in the EIS were attributed to narrow terms of reference and poor institutional culture. This article recommends the use of a dramaturgical approach to technical texts, and reveals the assumptions framing the dualist notion that one can unambiguously separate technical and social criticisms of technical projects.

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Ramesh Kumar, S., G. Renuka, Sheela Bijlwan, Ahmed H. R. Abbas, Smriti Sharma i K. B. Waghulde. "Nuclear Fusion Reactors: Challenges and Potential as a Future Energy Source". E3S Web of Conferences 540 (2024): 13014. http://dx.doi.org/10.1051/e3sconf/202454013014.

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This review article delves into the promising yet challenging realm of nuclear fusion reactors as a potential future energy source. The paper provides a comprehensive overview of global fusion research, highlighting its potential benefits and the technical obstacles that have hindered its widespread commercial adoption. Fusion energy, with its abundant resources, minimal waste generation, and low emissions, emerges as a long-term solution for a sustainable energy future. However, its technical complexities suggest that its widespread commercialization may not be realized until the end of the century. The article further explores the environmental compatibility, safety, and resource implications of fusion energy. A significant emphasis is placed on the paramount importance of safety in the development of fusion power reactors. The review underscores the need for robust safety cases, accident identification methods, and the establishment of internationally recognized safety standards. Additionally, the paper identifies knowledge gaps and areas necessitating further research, ensuring that fusion power stations meet rigorous safety objectives while minimizing environmental impact. Through a holistic examination of fusion’s potential and challenges, this review offers insights into its role in shaping the future energy landscape.

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Balakhanova, T. V., I. M. Chuiko, E. V. Parusov i E. V. Oliinyk. "Some aspects of the use of steel during out of reactor storage and transportation of spent nuclear fuel. (Review)". Fundamental and applied problems of ferrous metallurgy 37 (2023): 389–406. http://dx.doi.org/10.52150/2522-9117-2023-37-389-406.

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In the world, the nuclear industry is considered an ideal option for an environmentally friendly source of energy generation, based on the separation of the radioactive nuclide of the chemical element 235U. When generating electricity from nuclear power plants, the main disadvantage is the generation of radioactive waste. After spent fuel is removed from a nuclear reactor, it is placed in special containers containing absorption and retention elements. It is obvious that the storage and transportation of spent nuclear fuel plays an important role in the development and overall safety of the nuclear industry, and high-quality neutron-absorbing materials are the basis for the successful manufacture of reliable structures and containers. The development of modern neutron absorption materials ensures reliability, safety, storage duration, as well as reducing the cost of logistics operations associated with the transportation of radioactive waste. Based on the results of the analysis of scientific and technical sources, modern ideas about materials for the manufacture of containers, which are used for storage and transportation of nuclear fuel waste, are summarized. The advantages and disadvantages of the main materials used in the disposal of spent nuclear fuel are considered. It has been established that, from an economic point of view, the most rational material for storing and transporting radioactive waste is ferritic stainless steel with a high boron content, which, in addition to absorption abilities, is characterized by other properties required for this type of product. Since boron has a low ability to dissolve in both austenite and ferrite, this leads to the formation of borides of various types, which contribute to the embrittlement of the structural material. At the same time, the distribution of borides over the volume of a metal product is determined not only by a set of properties, but also by the protective properties of the material, as well as the manufacturability of the final product from it. Despite the fact that boron-containing steels of the ferritic class have been known for a long time, issues related to the processes of structure formation, increasing technological and operational properties still remain insufficiently studied and controversial. There is also no information on the influence of heat treatment on the formation of the structure and mechanical properties of finished products made of ferritic stainless steels. Successful solution of these scientific and technical problems will ensure the production of modern high-quality neutron-absorbing containers for off-reactor storage and transportation of spent nuclear fuel.

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Johnson, Chelsea, Nandini G, Santosh K. Balivada i Surya Prakash. "Radioactive Waste Management in a Medical Cyclotron Facility - A Review". International Journal of Health Technology and Innovation 1, nr 03 (23.12.2022): 20–23. http://dx.doi.org/10.60142/ijhti.v1i03.53.

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The cyclotron is a device used to create radioactive atoms with a short half-life (radioactive isotopes) that can be utilised for research and medical imaging. When nuclear and radiation facilities are utilized, serviced, or decommissioned, radioactive waste is produced. The amount of radioactive waste produced is greatly decreased by good operating procedures. Iodine-123, Technetium-99m, Iodine-131, Gallium-67 Thallium-201 and fluorine-18 fluorodeoxyglucose are among the radionuclides utilised in medicine. The most widely used gaseous/aerosol radionuclides are (aerosolized) technetium-99m, xenon-133, and krypton-81m. The use of radionuclides (radioactive element) for industrial process control and instrumentation, medical diagnostic and therapeutic purposes, as well as numerous uses in research, education, agriculture, geological exploration, construction, and other human endeavors, results in radioactive waste. These applications generate a variety of radioactive waste, which can come from sealed sources and be in solid, liquid, or gaseous form. If the trash containing considerable amounts of radionuclides is not handled properly, there may be serious concerns to both the environment and human health. Due to the wide variety of waste kinds addressed, special consideration must be paid to safety concerns and regulatory management. This article will examine the fundamental procedures for managing radioactive waste in compliance with the regulatory agencies like AERB (Atomic Energy Regulatory Board) and IAEA (International Atomic Energy Agency).

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Ravi, Rajesh, Oumaima Douadi, Manoranjitham Ezhilchandran, Mustapha Faqir, Elhachmi Essadiqi, Merouan Belkasmi i Shivaprasad K. Vijayalakshmi. "A practical approach-based technical review on effective utilization of exhaust waste heat from combustion engines". Energy Sources, Part A: Recovery, Utilization, and Environmental Effects 45, nr 4 (1.08.2023): 10010–33. http://dx.doi.org/10.1080/15567036.2023.2242321.

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Lambert, Timothy, i Xuan Hieu Nghiem. "Review of the Deployment of and Research into Generation III & IV Nuclear Fission Reactors for Power Generation". PAM Review Energy Science & Technology 1 (3.08.2015): 90–108. http://dx.doi.org/10.5130/pamr.v1i0.1387.

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Nuclear fission is one of the more popular and efficient sources of energy that has been used in the last few decades. In the setting of the ongoing worldwide debate of the energy problem, this paper will review the different types and generations of nuclear reactors, and do comparisons with other notable energy sources (biofuel and fusion). The current generations III, III+, IV of reactor (mostly pressurized water reactors), their thermal efficiency, technical (structure and configuration), lifetime, energy output and how the systems contrast are discussed. The paper was written by gathering information from UTS library online database, as well as online articles related to fission power, all sources dating from 2000s onwards. Nuclear fission power is a very dense energy source as it provides higher amount of free energy than other energy sources from the same amount of fuel. The drawback, which is the high amount of radioactive waste that accumulates over time, along with thermal efficiency are improved upon by the current and next generations of reactors.

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Froese, Annika, Zoe Felder i Steffen Drees. "The importance of social science research in nuclear waste management shown by three projects on public participation". Safety of Nuclear Waste Disposal 2 (6.09.2023): 245–46. http://dx.doi.org/10.5194/sand-2-245-2023.

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Abstract. The disposal of nuclear waste is not only a technical challenge but also a sensitive socio-political issue. Especially in Germany, the search for a final repository for highly radioactive waste is complicated by past and present societal conflicts surrounding the use of nuclear energy. Hence, safe nuclear waste management requires social science research that examines the nuclear waste problem in its social context. We illustrate this claim by presenting the results of three contract research projects dealing with public participation, commissioned by Germany's Federal Office for the Safety of Nuclear Waste Management (BASE). Public participation is central to the safety of nuclear waste management. First, the safety of disposal practices is often improved by the general public's critical input. Second, public participation may increase the acceptability of nuclear waste disposal in a particular region, which is important to ensure the successful implementation of waste management strategies. Third, public participation serves to preserve knowledge and maintain competence, since it keeps the topic of nuclear waste present in people's minds. Therefore, social science research that improves public participation measures makes a significant contribution to the safety of nuclear waste management. This contribution presents three projects that illustrate how social science can improve public participation. The first project surveyed the German population regarding the search for a final repository for highly radioactive waste. The second examined the utility of digital participation tools. The third project dealt with the legal, political, and cultural challenges of cross-border public participation. The first project surveyed a representative sample of the German population. Survey participants answered questions pertaining to the structure and current state of Germany's search for a final repository, their main concerns in relation to this search, and their desire to participate in the search. Results show that Germans are most concerned about safety issues and currently have little desire to actively participate in the search, but instead demand to be well informed. The results of this project allow BASE to adapt its public participation strategy to the German population's needs, thereby increasing its effectiveness. The second project examined the utility of digital participation tools in the context of the search for a final repository. Past events implemented by BASE were marked by the underrepresentation of young people, women, and also people with lower educational attainment and migrant backgrounds. First, the project team carried out a literature review that showed that the use of digital tools does not solve issues of underrepresentation. The team then used focus groups to demonstrate the importance of schools, appealing designs, and gamification when addressing young people. The project ended with a workshop wherein experts discussed the project's results and developed prototypes of digital tools to support BASE's efforts to engage young people. Reaching young people is crucial to preserving knowledge and increasing the acceptability of nuclear waste disposal, since today's younger generations will be affected by and responsible for the final repository. The third project dealt with the legal, political, and cultural challenges of implementing public participation across borders. BASE will have to facilitate public participation in multiple countries if the proposed site for the final repository is in close proximity to Germany's border. The project team first conducted a literature review to analyze the challenges of cross-border public participation. The second part consisted of in-depth case studies of three different planning procedures, conducted in Switzerland, Germany, and the Czech Republic. Finally, researchers conducted five regional case studies, covering regions in Denmark, the Netherlands, the Czech Republic and Poland, Austria, and France. The project resulted in a sketch of a model cross-border participation process, ensuring that BASE will be able to successfully implement such a process. These projects show that social science research can improve the quality of public participation measures. Since public participation is crucial to the safety of nuclear waste management, so are the social sciences.

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Scott, J. S., i R. A. Gibb. "Results of geoscience research in the Canadian Nuclear Fuel Waste Management Program: Introduction". Canadian Journal of Earth Sciences 26, nr 2 (1.02.1989): 341–44. http://dx.doi.org/10.1139/e89-032.

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Canada, along with other countries that are considering the permanent disposal of high-level radioactive wastes from nuclear power generation, is undertaking a program of research into deep geological disposal. This program, led by Atomic Energy of Canada Limited (AECL) with support from Energy, Mines and Resources Canada, other federal government departments, universities, and industrial consultants, has been in progress since early in 1973. Geoscience research, the subject of this symposium, complements research on fuel waste immobilization to provide the data and information essential to the design and assessment of a complete disposal concept involving both natural and engineered barriers to the migration of radioactive material from the waste vault.During the early phases of the program, prior to 1975, an evaluation of the potential of Canadian salt deposits for nuclear waste disposal, as well as a preliminary assessment of the suitability of other geological formations, was made. Because the Province of Ontario was, and remains, the principal region in Canada for nuclear power development and because resources available for geoscience research would not permit simultaneous, intensive research on a number of rock types, the decision was taken to direct the main thrust of the geoscience research toward plutonic igneous rocks of the Canadian Shield in Ontario (Scott 1979). Lesser studies of salt and other sedimentary formations, including seabed, are continuing within the Geological Survey of Canada.Because the rock mass surrounding the vault will provide the principal barrier to the migration of radionuclides, should these be released from the emplaced wastes, knowledge and understanding of potential pathways through the rock mass and of the mechanisms of radionuclide transport and retention within the rock mass over the functional lifetime of the vault are fundamental requirements.Accordingly, the objectives of the geoscience research program (Dormuth and Scott 1984) are the following:(1) Develop and apply techniques to define the physical and chemical properties of large rock masses and of fluids within these rock masses.(2) Use these techniques in selected field research areas to calibrate and evaluate models developed to calculate fluid flow and mass transport through a large rock mass containing a hypothetical underground nuclear fuel waste-disposal vault.(3) Establish procedures to evaluate quantitatively rock bodies for their potential as disposal sites and thereby acquire the capability to compare different rock bodies.(4) Determine the long-term stability of plutonic rock masses by assessing the potential disturbance by seismic activity, glaciation, meteorite impact, and other disruptive events and processes.To achieve these objectives it has been necessary to undertake simultaneously a large number of research tasks involving the disciplines of geology, geophysics, hydrogeology, geomechanics, geochemistry, and mathematics. Some of these tasks are concerned primarily with regional aspects of the Canadian Shield, such as stress distribution, glaciation, and tectonic history; others with details of the surface and subsurface geology and hydrogeology of specific field research areas; and still others with the development and application of exploration technology to detect and evaluate the structural characteristics of igneous rock masses of relatively high integrity and uniformity. Field and office studies are supported by laboratory investigations of the physical and chemical properties of plutonic rocks, with specific reference to origin, history, and ability to retard or transmit radionuclides.Deep exploratory drilling and detailed surface mapping are carried out at designated field research areas in the Canadian Shield. Geoscience work at research areas has the two-fold purpose of (i) testing new and existing exploration techniques for the evaluation of rock masses; and (ii) through application of these airborne, surface, and subsurface techniques, providing the field data necessary for the development of concepts and models that form the basis for establishing site-selection criteria and performing safety analyses.The latest research areas have been established at Atikokan, Ontario, an area underlain by granitic rocks, and at East Bull Lake north of Massey, Ontario, where gabbroic rocks are the dominant type. These research areas complement previously established research areas developed on granitic rocks at AECL properties at Chalk River, Ontario, and Pinawa, Manitoba, and at a research area, also on granitic terrane, near White Lake, Ontario, where work was done early in the program to test geophysical exploration and borehole-logging equipment.The ability to predict subsurface geological and hydrogeological conditions at future waste-disposal sites is one of the primary goals of geoscience research in the Canadian Nuclear Fuel Waste Management Program (CNFWMP). One of the most important program elements designed to test this predictive capability was the construction of the Underground Research Laboratory (URL) in the Lac du Bonnet Batholith near the site of the Whiteshell Nuclear Research Establishment. Airborne, surface, and borehole methods were used to develop a geological model on the site, and hydrogeological investigations were carried out to establish preconstruction groundwater characteristics. As the excavation of the URL facilities proceeded, the geological features encountered and the changes in the hydrogeological systems were carefully monitored. These data are being used to assess and improve the geological and hydrogeological models being developed for the rock mass surrounding the URL.The URL provides an excellent opportunity to (i) study the effect of excavation techniques, heat, and stress on a rock mass; (ii) simulate and study the complex systems that may exist in a disposal vault environment; and (iii) develop and test shaft- and drift-sealing techniques. Recently, a bilateral agreement between AECL and the United States Department of Energy was signed for co-operative research on nuclear fuel waste disposal. A substantial part of this co-operative effort will be directed toward extension of the URL shaft beyond its present depth of 240 m and conducting a variety of nonnuclear experiments within the shaft and excavated chambers of the URL.From the time of formalization of CNFWMP over 10 years ago, a concerted effort has been made by AECL and other program participants to ensure both peer review of and widespread accessibility to results of research arising from CNFWMP. This symposium is the third to be sponsored by the Geological Association of Canada (GAC)—the two previous symposiums were held at GAC annual meetings in Winnipeg in 1982 and Toronto in 1978. In addition to these major symposia, general information meetings sponsored by AECL have been held annually at various centres across Canada, and research elements of CNFWMP formed a significant part of the technical program for an international meeting held by the Canadian Nuclear Society in Winnipeg in September 1986.Since 1979 the CNFWMP review process has been further enhanced by the Technical Advisory Committee chaired by L. W. Shemilt, McMaster University. This committee, comprising members nominated by major Canadian scientific and technical societies including the Canadian Geoscience Council, has annually provided a publicly available report of constructive criticism and recommendations for improvement in the research content of CNFWMP.During the second half of 1988 it is expecte

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Mallouppas, George, i Elias Ar Yfantis. "Decarbonization in Shipping Industry: A Review of Research, Technology Development, and Innovation Proposals". Journal of Marine Science and Engineering 9, nr 4 (13.04.2021): 415. http://dx.doi.org/10.3390/jmse9040415.

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This review paper examines the possible pathways and possible technologies available that will help the shipping sector achieve the International Maritime Organization’s (IMO) deep decarbonization targets by 2050. There has been increased interest from important stakeholders regarding deep decarbonization, evidenced by market surveys conducted by Shell and Deloitte. However, deep decarbonization will require financial incentives and policies at an international and regional level given the maritime sector’s ~3% contribution to green house gas (GHG) emissions. The review paper, based on research articles and grey literature, discusses technoeconomic problems and/or benefits for technologies that will help the shipping sector achieve the IMO’s targets. The review presents a discussion on the recent literature regarding alternative fuels (nuclear, hydrogen, ammonia, methanol), renewable energy sources (biofuels, wind, solar), the maturity of technologies (fuel cells, internal combustion engines) as well as technical and operational strategies to reduce fuel consumption for new and existing ships (slow steaming, cleaning and coating, waste heat recovery, hull and propeller design). The IMO’s 2050 targets will be achieved via radical technology shift together with the aid of social pressure, financial incentives, regulatory and legislative reforms at the local, regional and international level.

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Pasquato, Leone, Christoph Strangfeld, Esko Strömmer, Sergej Johann, Vera Lay, Christian Köpp i Ernst Niederleithinger. "Embedded sensors system to monitor cemented waste drums". Safety of Nuclear Waste Disposal 2 (6.09.2023): 21. http://dx.doi.org/10.5194/sand-2-21-2023.

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Abstract. BAM (Federal Institute for Materials Research and Testing) is developing an electronic measurement system to be placed inside a waste drum, which will be filled with concrete. The goal of this measurement system is to monitor the process of hardening and the evolution of the concrete itself over time to indirectly identify potential defects such as corrosion or cracking. The measured parameters are humidity, temperature, and pressure. In this regard, particular attention was given to the design of the electronic board's enclosure, to allow the sensors to measure the state of the concrete without being in direct contact with it. In the scope of the European Commission's project of PREDIS, the supply of power to the battery-less sensors and the data acquired by such sensors are transmitted through the metallic waste drum by an innovative wireless technology developed by VTT (Technical Research Centre of Finland Ltd) in order to ensure long-term operation, while keeping the integrity of the sealed container. The sensing system is made of a chain of small units, called SensorNodes. Each SensorNode includes two off-the-shelf sensors, with one for relative humidity and temperature and one for pressure and temperature. A SensorNode is designed to have a unique identifier, in order to be connected to other units while being uniquely discoverable by a standard communication protocol. In this way, a distributed matrix of measurement points is created. One of the most challenging tasks in designing a measurement system to run in a harsh environment (such as hardening concrete) is to let the sensors sense the external environment without damaging the sensors themselves. In order to keep the external environment away from the electronic board while still letting the sensors measure the concrete behaviour, holes have been drilled through the lid and covered from the inside with a layer of porous membrane. The membrane's pores allow water and gas particles to pass through and let the enclosed air equilibrate with the external environment. With the help of the developed sensors, monitoring concrete in cemented waste drums will be possible. The derived data will also serve as the basis for ongoing modelling approaches for digital twins within the PREDIS project. Overall, the sensors provide a means of enabling safe nuclear waste management through advanced monitoring.

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Olkhovyk, Yu. "Problematic Issues Regarding the Quantity and Properties of Vitrified High-Level Waste Returning to Ukraine". Nuclear and Radiation Safety, nr 2(82) (6.06.2019): 26–29. http://dx.doi.org/10.32918/nrs.2019.2(82).05.

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Safety justification of long-term storage and further disposal of vitrified high-level waste returning to Ukraine shall be based on reliable information about their physical and chemical characteristics, which include not only the radionuclide composition, but also the estimated evolution of Na-Al-P glass properties in the conditions of potential longterm effect of unfavorable factors. The paper indicates an inconsistency of dose coefficients, which according to the Energoatom standards shall be used to calculate the amount of high-level waste returning to Ukraine after storage and processing of VVER-440 spent nuclear fuel, with the regulatory requirements of the country supplying vitrified high-level waste. The quantitative assessment of transuranium radionuclides and technetium 99 entering the glass matrix also requires a critical review. The research considered the possibility of uncertainty related to the structural homogeneity of a glass matrix due to the underestimation of cracking and crystallization processes that occur in the package in sodium-aluminophosphate glass cooling. The presence of a large number of rare-earth oxides in sodium-aluminophosphate glass contributes to its crystallization in slow cooling with monazite formation. These phenomena can lead to a partial conversion of amorphous glass into a crystalline phase accompanied by 1-2 order increase in the velocity of leaching of elements. When developing technical requirements for vitrified high-level waste returning to Ukraine, it is necessary to insist on the provision of experimentally determined parameters of the structural homogeneity of glass blocks. There is a need for obtaining experimentally defined parameters of radiation resistance of a sodium-aluminophosphate matrix under the influence of a dose that can be accumulated over a period of 100 years using accelerated self-radiation methods.

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Aredokou, Louis Olorounto, Victorin Kouamy Chegnimonhan, Kapen Pascalin Tiam, Clotilde Guidi T. i Basile Kounouhewa. "Thermodynamic Modelling, Technical and Operational Issues of Supercritical Carbon Dioxide Power Generation Cycles for Industrial Applications: A Literature Review". IRA-International Journal of Applied Sciences (ISSN 2455-4499) 18, nr 4 (29.12.2023): 85. http://dx.doi.org/10.21013/jas.v18.n4.p3.

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Future electricity production systems will be able to harness the power of supercritical carbon dioxide (S-CO2) as it moves through thermal cycles. It serves the same goal as sources of energy such as fossil fuels, nuclear power, solar power, and the recovery of waste heat (or surplus heat from industrial processes). When the heat source temperature is between 350°C and 800°C, CO2 as a working fluid exhibits excellent thermal efficiency. Its novel technological benefits over conventional steam Rankine cycles, such as the use of small turbo gear and compact heat exchangers, have captured the attention of scientists. It has excellent operational flexibility and may induce significantly cheaper energy costs. Aligned with these goals, this paper presents a panoramic work, exploring the current state of the art of S-CO2 power generation, with a particular emphasis on the technical and operational perplexities. After providing a comprehensive overview of the thermodynamic principles that underpin this study, the foundation is established for an engaging discourse on the continuous research and development of supercritical carbon dioxide (S-CO2) cycles in power generation. Upon delving into the thermodynamic facets of CO2 that propel this investigation, the spotlight is cast upon dissecting the existing state of research and development of S-CO2 cycles in power generation before transitioning into encapsulating the principal domains of application and noteworthy thermodynamic modelling inquiries of S-CO2 cycles. The present advancements and hurdles within the primary application areas are succinctly summarized, while future research trends are identified.

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Mallants, Dirk, John Phalen i Hef Griffiths. "Deep borehole disposal of intermediate-level waste". Safety of Nuclear Waste Disposal 1 (10.11.2021): 263–64. http://dx.doi.org/10.5194/sand-1-263-2021.

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Abstract. Around the world, deep borehole disposal is being evaluated for intermediate-level waste (ILW), high-level waste (HLW), spent nuclear fuel (SNF), separated plutonium waste and some very high specific activity fission product waste. In Australia, long-lived ILW from research reactors and radiopharmaceutical production represents the principal waste stream that requires deep geologic disposal. Whilst the Australian government has not yet made a decision on its preferred strategy for ILW disposal, deep borehole disposal of small volumes of ILW would be a more cost-effective and modular solution compared to a conventional geologic disposal facility (GDF). CSIRO, ANSTO and SANDIA have created an international partnership to execute a full-scale borehole research, development and demonstration (RD&D) project in Australia. The project will demonstrate the technical feasibility of the long-term safety of borehole disposal in deep geological formations. The execution of this project could also demonstrate options for nuclear waste disposal that would reduce proliferation risks, potentially up to the termination of compliance with international safeguards requirements. The RD&D includes demonstration of surface handling and waste/seal emplacement capabilities, basic research on foundational science areas, and full-scale field testing in both a deep characterization borehole and a larger-diameter (0.7 m or 27.5 inch) 2000 m deep demonstration borehole. The multi-barrier system designed for such a deep disposal borehole concept places much less reliance on engineered barriers at the disposal zone to achieve safety as compared to a conventional GDF. It rather relies on geological features for waste containment. The concept being explored uses disposal containers with primary waste packages, such as vitrified waste canisters, inside; to be both cost effective and fit for purpose, such a container could have a mild steel-based structural component with copper coating. A critical review of six coating technologies showed that cold spray has the greatest advantages, such as minimal porosity and compressive residual stress. The RD&D has delivered novel enabling tools that assist with site screening, borehole design and post-closure safety assessments. For instance, an automated geological fault mapping and meshing tool was developed that assists with ranking the suitability of potential disposal sites based on proximity to faults. New codes were developed for better representation of fault zones in 2D/3D numerical flow and transport models, while also being more efficient to execute. Post-closure safety assessments tested the sensitivity of long-term safety with respect to disposal depth, rock permeability and sorption. Heat transport calculations explored the sensitivity of temperature evolution within the borehole to parameters such as heat load, borehole depth, geothermal gradients and rock thermal conductivity. For verification of host rock tightness while also demonstrating the absence of recent groundwater, a new noble gas analytical facility has been established for measuring rare noble gases in mineral fluid inclusions as indicators of very old pore fluids.

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Chizek, Martin. "Programmable Logic Device (PLD) Safety Design Approach". Journal of System Safety 55, nr 1 (1.03.2019): 32–41. http://dx.doi.org/10.56094/jss.v55i1.54.

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Programmable Logic Devices (PLDs) in ordnance fuze and ignition systems have well-defined design and verification requirements based on U.S. Department of Defense (DoD) Safety Review Board guidelines and military standards. However, there are few established safety design and verification requirements for PLDs used in non-fuze safety-significant applications. The primary objective of this paper is to (1) establish a process that assures that PLDs in products and systems are developed and tested to a level of rigor commensurate with the safety risk of the specified application, including fuze and non-fuze safety systems, and (2) to comply with recent guidance from DoD Software System Safety Technical Review Panels on firmware and programmable logic safety assurance. The paper’s secondary objective is to make the PLD safety process applicable to non-DoD and commercial programs such as autonomous vehicles, aerospace and energy systems. To meet this objective, this document incorporates best practices of NASA, commercial aviation, the Nuclear Regulatory Commission (NRC), and from international programmable electronic functional safety standards.

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Tomkiv, Y., T. Perko, R. Sala, N. Zeleznik, M. Maitre, T. Schneider i D. H. Oughton. "Societal uncertainties recognised in recent nuclear and radiological emergencies". Radioprotection 55 (21.04.2020): S151—S155. http://dx.doi.org/10.1051/radiopro/2020025.

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The paper aims to stimulate reflection and debate on the issue of uncertainty as a key component of nuclear or radiological emergency management. It identifies and discusses different types of uncertainties that appeared during and after real emergencies. For this, seven different case studies of nuclear and radiological events have been analysed using three separate methodological approaches: i) case descriptions (document review); ii) media analysis; and iii) semi-structured interviews. The overall objective was to elucidate the understanding and response to scientific and social uncertainties, and related ethical issues. A range of different uncertainties were identified and roughly grouped into categories related to: 1) technical and measurement uncertainties; 2) societal impacts and societal framing; 3) contradictory information and communication aspects; 4) ethical aspects. This analysis intends to inform emergency managers on the types of uncertainties that may appear to different actors during nuclear or radiological emergency. The results should serve to stimulate preparation on the uncertainty response and by this also to reduce some of the identified uncertainties.

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P, Kudryavtsev. "Development of decontamination and detergents for the nuclear industry". International Journal of Hydrology 5, nr 4 (6.08.2021): 192–200. http://dx.doi.org/10.15406/ijh.2021.05.00280.

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At the enterprises of the radiochemical industry in the world, the task is to clean the technological and research equipment, overalls, and personnel from contamination with radioactive products. This task is especially relevant in case of emergencies, for example, such as an accident at a nuclear power plant in Fukushima, Japan. A review of the deactivation methods currently used is reviewed. It has been shown that the most typical pollutants are mixtures of radionuclides 137Cs, 144Ce, 144Pr, 90Sr, and 239Pu. All these elements are prone to the formation of chelate complexes. Therefore, complexing substances should be an essential component of deactivation solutions that form stable, water-soluble complex compounds with these radionuclides. When creating the recipe, we chose those complexing agents with the most persistent complex compounds with the expected pollutants. For research and testing in real conditions, we have prepared three types of technical detergents of various compositions with the code name MDS for decontaminating various surfaces, equipment, and workwear. The composition of these preparations consists mainly of an optimized mixture of surfactants, complexing agents, corrosion inhibitors, and processing aids. The studies were conducted to evaluate the possibility of using these funds for deactivation of premises, equipment, washing clothes in the Federal Unitary Enterprise "Mayak" and at its branch NIKIET in town Zarechny at Beloyarskyaya Nuclear Power Station in Russia. The effectiveness of deactivation was judged by the amount of residual contamination of the surface of the samples. The deactivating ability of MDS preparations for stainless, carbon steel, and plastic contaminated with β- and α-emitting nuclides was tested. The possibility of using MDS detergents for the deactivation of platinum ampoules stored as radioactive waste was assessed. The possibility of using MDS detergents for the deactivation of fabric materials, including underwear and work clothes, was also evaluated. The tests showed the high efficiency of the developed detergent MDS compared to the existing and currently used deactivation agents.

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Swersky, Adam, Daniel Borja-Cacho, Zach Deitch, Bartley Thornburg i Riad Salem. "Portal Vein Recanalization–Transjugular Intrahepatic Portosystemic Shunt (PVR-TIPS) Facilitates Liver Transplantation in Cirrhotic Patients with Occlusive Portal Vein Thrombosis". Seminars in Interventional Radiology 40, nr 01 (luty 2023): 038–43. http://dx.doi.org/10.1055/s-0043-1764409.

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AbstractPortal vein thrombosis (PVT) is a heterogeneous condition with multiple possible etiologies and to varying degrees has historically limited candidacy for liver transplant (LT) in the cirrhotic patient population due to resultant difficulties in constructing a robust portal vein anastomosis. While intraoperative approaches to managing PVT are well-described, methods which approximate normal portal physiology are not always feasible depending on the extent of PVT, and other nonphysiologic techniques are linked with substantial morbidity and poor long-term outcomes. Portal vein recanalization–transjugular intrahepatic portosystemic shunt (PVR-TIPS) creation is an efficacious method of restoring physiologic portal flow in cirrhotic patients prior to LT allowing for end-to-end PV anastomosis, and is the product of decades-long institutional expertise in TIPS/LT and the support of a multidisciplinary liver tumor board. To follow is a review of the pertinent pathophysiology of PVT in cirrhosis, the rationale leading to the development and subsequent evolution of the PVR-TIPS procedure, technical lessons learned, and a summary of outcomes to date.

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Malchair, F., i C. Maccia. "Practical advices for optimal CT scanner dose in children". Radioprotection 55, nr 2 (kwiecień 2020): 117–22. http://dx.doi.org/10.1051/radiopro/2020046.

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Radiation protection and dose optimisation in computerized tomography (CT) for pediatric patients are of utmost importance because of the potential risk of cancer induction by exposure to ionizing radiation. A review of available technical features in modern CT machines aiming at reducing and/or optimizing patient dose was performed. Practical advices to operators were listed according to dose-related technical solutions studied to decrease the doses and to practically implement dose optimisation.

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Jobin, Jean-François. "Étude de certains aspects du droit nucléaire canadien". Articles 22, nr 2 (12.04.2005): 347–70. http://dx.doi.org/10.7202/042440ar.

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The law respecting nuclear energy has to date been the subject of relatively few studies in Canada. Considering, however, the growing importance of nuclear energy as a new or additional form of energy, besides oil, gas, coal and hydroelectric power, and on the other hand, the increase in public concern about the possible consequences of the nuclear option, especially on health and the environment, this area of law is undoubtedly bound to experience a major development. The purpose of the present article is to study existing federal legislation on the matter, as well as its effects on certain provincial jurisdictions, more particularly in Quebec. The author, after recalling certain technical data concerning components and functions of nuclear reactors, proceeds to analyse the main intervenors in the nuclear field, as contemplated by the Atomic Energy Control Act. One cannot help but acknowledge that the Atomic Energy Control Board, by means of its important supervisory and regulatory powers, intervenes at all stages of the nuclear cycle. The author also studies the constitutional basis for the federal intervention in this field of activity. After eliminating the national defence power, the national dimension theory and the emergency power as possible alternatives, he concludes that while Parliament may perhaps invoke its residuary power, its declaratory power appears as the surest constitutional basis for asserting its legislative authority over that particular matter. In the last part of the article, the author attempts to emphasize the effects of federal intervention on provincial property rights over uranium mines, and on provincial jurisdictions over labour relations, health and safety at the workplace and environmental protection. This analysis points out that provincial legislative authority over the management and development of their natural resources is not only inapplicable in respect of uranium, but that their property rights over uranium mines are rather precarious. It seems clear, further, that jurisdiction over labour relations within nuclear undertakings lies exclusively with the federal authority. One could argue that such is also the case with those aspects of nuclear undertakings which are connected with workers' health and safety as well as environmental protection, since those matters are intimately linked with the control of atomic energy. Two main conclusions can be drawn from this study. Firstly, it appears certain that Parliament, in legislating as it did, intended to regulate the whole nuclear energy cycle, from the extraction of uranium ore to the ultimate disposal of nuclear waste. Secondly, that authority could hardly be challenged by provinces or any other interested party, at least on constitutional grounds.

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Imanzadeh, Amir, Nima Kokabi, Sarvenaz Pourjabbar, Igor Latich, Jeffrey Pollak, Hyun Kim i Gowthaman Gunabushanam. "Safety and Efficacy of Percutaneous Cholecystostomy for Emphysematous Cholecystitis". Journal of Clinical Imaging Science 10 (27.03.2020): 9. http://dx.doi.org/10.25259/jcis_145_2019.

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Objective: The objective of the study was to evaluate the safety and efficacy of percutaneous cholecystostomy (PC) in treating critically ill patients with emphysematous cholecystitis who were deemed poor surgical candidates. Materials and Methods: The Institutional Review Board exemption was obtained for this retrospective study. Patients with emphysematous cholecystitis who were deemed to be poor operative candidates by the treating surgeon and underwent PC placement between May 2008 and April 2017 at a single institution were identified through a medical records search. Demographics, laboratory values, imaging data, procedural technique, complications, hospitalization course, clinical outcome, and survival data were obtained. Results: Ten consecutive patients were included, with a mean age of 75.0 ± 12.2 years, including six men and four women. The most common comorbidity was diabetes (60%, 6/10) followed by hypertension (40%, 4/10). Intraluminal or intramural gas as well as gallbladder wall thickening were noted in all patients. Procedure technical success rate was 100%. There was a complete resolution of symptoms in 90% (9/10) of patients at a mean of 2.9 ± 1.4 days post-procedure. Thirty-day survival rate was 90% (9/10); one patient died on the 6th post- procedure day from sepsis. Two more deaths occurred within a year after PC from unrelated causes. About 50% (5/10) of patients underwent elective cholecystectomy at a median interval of 69 days post-procedure. In 40% (4/10) of patients, cholecystostomy was the definitive treatment, with tube removal at a median of 140 days post- procedure. Conclusion: PC appears to be a safe and generally effective alternative management option in patients with emphysematous cholecystitis that is considered very high risk for surgery.

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Myazin, Nikita Sergeevich, Vadim Vladimirovich Davydov, Victoria Valerevna Yushkova i Vasiliy Yurevich Rud'. "A new method of determining the state of water and agricultural areas in real time". Environmental Research, Engineering and Management 75, nr 2 (3.09.2019): 28–35. http://dx.doi.org/10.5755/j01.erem.75.2.22352.

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Paper discusses the technique of environmental condition monitoring based on the phenomenon of nuclear magnetic resonance (NMR). Express control is an integral part of agriculture, because when working on farms or in fields there are situations when it is physically impossible to deliver samples for research to a stationary laboratory (results are needed urgently or samples can change their properties during transportation). A brief review of the existing methods for monitoring the states of media in the express mode was carried out, their shortcomings were revealed and a new technical solution to this problem was proposed. For a small-sized NMR spectrometer, a new magnetic system and a signal registration circuit have been developed, which makes it possible to detect the NMR signal at different frequencies, thus registering the signal spectrum. In addition, this design also allows measuring the longitudinal and transverse relaxation times of the medium. With the help of the proposed technique, studies of various media have been carried out; the results of these studies are presented.

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Mihama, Toru, Spencer Liem, Nicholas Cavarocchi i Hitoshi Hirose. "Outcomes of out-of-hospital extracorporeal membrane oxygenation transfers: significance of initiation site and personnel". Perfusion 35, nr 7 (17.01.2020): 633–40. http://dx.doi.org/10.1177/0267659119897784.

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Background: Extracorporeal membrane oxygenation is an accepted therapy option for refractory cardiac or respiratory failure. The outcomes of cases initiated at non–extracorporeal membrane oxygenation centers and subsequently transported for management to an extracorporeal membrane oxygenation center require further investigation. Methods: Retrospective institutional review board–approved database research and chart reviews were performed on referrals for extracorporeal membrane oxygenation initially admitted to an outside non–extracorporeal membrane oxygenation center hospital (OSH) then transferred to our extracorporeal membrane oxygenation center (Thomas Jefferson University Hospital (TJUH)). Unstable patients were placed on extracorporeal membrane oxygenation at OSH (Group A) before transport, while others were initiated at our certified extracorporeal membrane oxygenation center (Group B) upon arrival. Group A was further subdivided into patients cannulated by OSH personnel (Group AOSH) or TJUH transport team (Group ATJUH). Outcomes and complications were compared between the different initiation sites and personnel. Results: A total of 108 patients were transferred from August 2010 to June 2018. The technical complication rate for all Group A patients was 33/49 (67%), while that of Group B was 24/59 (41%); p = 0.006. Within Group A, Group AOSH had a greater technical complication rate with 29/33 (88%) than Group ATJUH with 4/16 (25%); p < 0.001. extracorporeal membrane oxygenation survival rate was 34/49 (69%) in Group A and 43/59 (73%) in Group B; p = 0.690. The extracorporeal membrane oxygenation survival rate for Group AOSH and Group ATJUH was 21/33 (64%) and 13/16 (81%), respectively; p = 0.210. Conclusion: Promising extracorporeal membrane oxygenation survival rates were observed in transferred patients. The complication rates related to cannulation technique were significantly higher when patients were initiated at non–extracorporeal membrane oxygenation centers, especially when placed by personnel from non–extracorporeal membrane oxygenation centers.

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Silva, Claudio, i Ema Leal. "Venous Air Microembolism in Chest CT Angiography: Evidence of Normalization of Deviance Phenomenon". Indian Journal of Radiology and Imaging 31, nr 04 (październik 2021): 805–8. http://dx.doi.org/10.1055/s-0041-1741093.

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Abstract Purpose This article provides evidence that detection of venous air microbubbles (VAMB) in chest computed tomography angiography (CTA) can be an indicator for “normalization of deviance” phenomenon in CT. Method and Materials Institutional review board-approved retrospective study, with waiver for informed consent. Contrast-enhanced chest CT performed during 6 months were reviewed for presence of VAMB in venous segments visible in chest CT (subclavian, brachiocephalic vein, superior vena cava) and cardiac chambers. VAMB volumes were quantified through a semiautomatic method (MIAlite plugin for OsiriX), using a region of interest (ROI) covering the bubble. With basal results, protocols for correct injection technique were reinforced, and VAMB were estimated again at 1 and 3 months. Six months later, questionnaires were sent to the CT technologists to inquire about their perception of VAMB. Descriptive measures with central distribution and dispersion were performed; statistical significance was considered at p < 0.05. Results A total of 602 chest CTA were analyzed, 332 were women (55.14%), with a median age of 58 (interquartile range [IQR] 44–72) years. Among those, 16.11% (100 cases) presented VAMB. Most were emergency department patients (51.6%), male (50.3%), with a median age of 54 (IQR 26) years. There was no difference on detection of VAMB regarding sex (p = 0.19), age (p = 0.46), or referral diagnosis (p = 0.35). Mean air bubbles volume was 0.2 mL (range 0.01–3.4 mL). After intervention, the number of exams with VAMB dropped to 3.29 % (3/91) (p < 0.001). On the 6-month query, 50% of the technicians still considered that VMAB is inevitable, and 60% thought that the occurrence is not associated to risk, and therefore, not actionable. Conclusion VAMB are a frequent finding in chest CTA, and being independent from patient-related variables, it is likely due to technical issues such as intravenous access manipulation during the exam. Reduction after reinforcement of proper performance, and certification of a low concern from CT technicians for any risk associated, provides evidence that there is normalization of deviance in this everyday procedure.

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Birkholzer, Jens T., LianGe Zheng, Prasad Nair i Timothy Gunter. "The role of international collaboration in the United States geologic disposal research program". Safety of Nuclear Waste Disposal 2 (6.09.2023): 29–30. http://dx.doi.org/10.5194/sand-2-29-2023.

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Abstract. More than a decade ago, the United States disposal program discontinued all research activities focused on the unsaturated fractured tuff formation at Yucca Mountain as the geologic disposal site for spent fuel and high-level radioactive waste. A new research and development (R&D) program was initiated to provide a sound technical basis for alternative disposal options across clay, crystalline, and salt rocks. The goals of this broad program were (and still are) to (1) increase confidence in the robustness of generic disposal concepts, (2) develop the science and engineering tools needed to support disposal concept implementation, and (3) conduct R&D on the direct disposal of existing dual-purpose (storage and transportation) canisters. Recognizing the benefits of international collaboration toward the common goal of safely and efficiently managing the back end of the nuclear fuel cycle, the program emphasized international cooperation as an effective strategy for sharing information and knowledge. In a multi-laboratory effort coordinated by Lawrence Berkeley National Laboratory, the United States Department of Energy (DOE) program established formal and informal cooperation partnerships with several international initiatives and institutions and developed a number of collaborative R&D activities in important research areas, such as engineered barrier integrity, near-field perturbations, radionuclide transport, performance assessment, and methods for characterization and monitoring of engineered and natural barriers. This presentation gives an overview of these R&D activities, with a specific focus on activities that improve our current understanding of the coupled thermal–hydrological–mechanical–chemical (THMC) processes occurring in engineered and natural barriers. We start with a brief review of selected international collaboration initiatives and then describe a few specific collaboration projects. We focus specifically on such studies that use experimental data sets provided by international research cooperation for joint modeling work to increase confidence in performance-relevant predictions of coupled processes. Overall, the focus on international collaboration has allowed deep engagement of US researchers with the international waste management R&D community in terms of best practices, new scientific advances, state-of-the-art simulation tools, new monitoring and performance confirmation approaches, and lessons learned. The joint R&D with international researchers, worldwide sharing of knowledge and experience, and access to relevant data and experiments from a variety of host rocks have helped our researchers to significantly improve their understanding of the current technical basis for disposal in a range of potential host rock environments. International collaboration also provides ample opportunity for training and educating junior staff that are well suited to move the United States disposal research program forward into the next decades, a promising avenue for developing a next-generation workforce of disposal scientists.

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Jang, Hye Young, Kyoung Won Kim, So Yeon Kim, Jin Sil Kim, Sang Hyun Choi, Se-Young Kim i Sung-Gyu Lee. "Visibility of the graft hepatic artery using superb microvascular imaging in liver transplantation recipients: initial experience". Acta Radiologica 59, nr 11 (10.02.2018): 1326–35. http://dx.doi.org/10.1177/0284185118757275.

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Background Hepatic artery (HA) obstruction is one of the most threatening complications following liver transplantation (LT); however, conventional color Doppler imaging (CDI) suffers from technical limitations regarding the visualization of fine vessels and low-velocity blood flow. Purpose To test the visibility of HA in postoperative evaluation of LT using a superb microvascular imaging (SMI). Material and Methods This retrospective study was approved by our institutional review board. Fifty-five consecutive patients (58 grafts; mean age = 56 years) who underwent LT with Doppler ultrasonography (US) on postoperative day 1 were included. We compared the subjective visibility of HA and objective measurements of HA caliber, visible HA length on CDI, monochrome SMI (mSMI), contrast-enhanced mSMI (CE-mSMI), and contrast harmonic imaging (CHI). Reproducibility of HA caliber measurements on SMI techniques were also evaluated by using intraclass correlation coefficients (ICCs). Results The subjective image quality for visibility of HA tended to be graded higher with mSMI than CDI, and with CE-mSMI than mSMI ( P < 0.001). The overall reproducibility of HA caliber measurements was good to excellent for both mSMI and CE-mSMI (ICC = 0.674–0.855). HA caliber measurements on mSMI and CE-mSMI strongly correlated with CHI ( R = 0.785, 0.798, P < 0.001), while mean HA length on mSMI was significantly longer than on CDI (1.88 ± 0.83 vs. 1.42 ± 1.01cm, P = 0.004), and even longer on CE-mSMI (vs. 3.28 ± 1.11 cm, P < 0.001). Conclusion The mSMI technique shows good reproducibility and correlates well with currently used methods for postoperative evaluation of HA in LT recipients. It is further improved by administration of an US contrast agent.

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Wildeboer, Rogier R., Christophe K. Mannaerts, Ruud J. G. van Sloun, Lars Budäus, Derya Tilki, Hessel Wijkstra, Georg Salomon i Massimo Mischi. "Automated multiparametric localization of prostate cancer based on B-mode, shear-wave elastography, and contrast-enhanced ultrasound radiomics". European Radiology 30, nr 2 (10.10.2019): 806–15. http://dx.doi.org/10.1007/s00330-019-06436-w.

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Abstract Objectives The aim of this study was to assess the potential of machine learning based on B-mode, shear-wave elastography (SWE), and dynamic contrast-enhanced ultrasound (DCE-US) radiomics for the localization of prostate cancer (PCa) lesions using transrectal ultrasound. Methods This study was approved by the institutional review board and comprised 50 men with biopsy-confirmed PCa that were referred for radical prostatectomy. Prior to surgery, patients received transrectal ultrasound (TRUS), SWE, and DCE-US for three imaging planes. The images were automatically segmented and registered. First, model-based features related to contrast perfusion and dispersion were extracted from the DCE-US videos. Subsequently, radiomics were retrieved from all modalities. Machine learning was applied through a random forest classification algorithm, using the co-registered histopathology from the radical prostatectomy specimens as a reference to draw benign and malignant regions of interest. To avoid overfitting, the performance of the multiparametric classifier was assessed through leave-one-patient-out cross-validation. Results The multiparametric classifier reached a region-wise area under the receiver operating characteristics curve (ROC-AUC) of 0.75 and 0.90 for PCa and Gleason > 3 + 4 significant PCa, respectively, thereby outperforming the best-performing single parameter (i.e., contrast velocity) yielding ROC-AUCs of 0.69 and 0.76, respectively. Machine learning revealed that combinations between perfusion-, dispersion-, and elasticity-related features were favored. Conclusions In this paper, technical feasibility of multiparametric machine learning to improve upon single US modalities for the localization of PCa has been demonstrated. Extended datasets for training and testing may establish the clinical value of automatic multiparametric US classification in the early diagnosis of PCa. Key Points • Combination of B-mode ultrasound, shear-wave elastography, and contrast ultrasound radiomics through machine learning is technically feasible. • Multiparametric ultrasound demonstrated a higher prostate cancer localization ability than single ultrasound modalities. • Computer-aided multiparametric ultrasound could help clinicians in biopsy targeting.

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Evrard, Olivier, Thomas Chalaux-Clergue, Pierre-Alexis Chaboche, Yoshifumi Wakiyama i Yves Thiry. "Research and management challenges following soil and landscape decontamination at the onset of the reopening of the Difficult-to-Return Zone, Fukushima (Japan)". SOIL 9, nr 2 (6.09.2023): 479–97. http://dx.doi.org/10.5194/soil-9-479-2023.

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Abstract. Twelve years after the nuclear accident that occurred at the Fukushima Dai-ichi Nuclear Power Plant (FDNPP) in March 2011, radiocesium contamination (with a large dominance of 137Cs, with a 30-year half-life) remains a major concern in various municipalities of north-eastern Japan. The Japanese authorities completed an unprecedented soil decontamination programme in residential and cultivated areas affected by the main radioactive plume (8953 km2). They implemented a complex remediation programme scheme to remediate soils that are fundamental to life on Earth, relying on different decision rules depending on the waste type, its contamination level and its region of origin, after delineating different zones exposed to contrasted radiation rates. The central objective was not to expose local inhabitants to radioactive doses exceeding 1 mSv yr−1 in addition to the natural levels. At the onset of the full reopening of the Difficult-to-Return Zone (DTRZ) in spring 2023, the current review provides an update of a previous synthesis published in 2019 (Evrard et al., 2019). Although this ambitious soil remediation and reconstruction programme has almost been completed in the 12 municipalities of Fukushima Prefecture in which an evacuation order was imposed in at least one neighbourhood in 2011, from the 147 443 inhabitants who lived there before the accident, only 29.9 % of them had returned by 2020. Waste generated by decontamination and tsunami cleaning/demolition work is planned to have been fully transported to (interim) storage facilities by the end of 2023. The cost of the operations conducted between 2011 and 2020 for the so-called “nuclear recovery” operations (including decontamination) was estimated by the Board of Audit of Japan in 2023 as JPY 6122.3 billion (∼ EUR 44 billion). Decontamination of cropland was shown to have impacted soil fertility, and potassium fertilisation is recommended to limit the transfer of residual radiocesium to new crops. In forests that cover 71 % of the surface area of Fukushima Prefecture and that were not targeted by remediation, radiocesium is now found in the upper mineral layer of the soil in a quasi-equilibrium state. Nevertheless, 137Cs concentrations in forest products (including wood for heating and construction, wild plants, wildlife game, mushrooms) often keep exceeding the threshold values authorised in Japan, which prohibits their exploitation in the area affected by the main plume. Radionuclides from forests were shown to be exported in dissolved and particle-bound forms to downstream river systems and floodplains, although multiple monitoring records showed the continuous decrease in radiocesium concentrations in both river water and sediment across the main plume between 2011 and 2021. Fish contamination is now generally found to be below the threshold limits although reputational damage remains a major concern for local fishing communities. The remobilisation of radiocesium from sediment accumulated in reservoirs of the region is also of potential concern as it may lead to secondary contamination of fish or irrigation waters supplied to decontaminated fields. Overall, this synthesis demonstrates the need to continue monitoring post-accidental radiocesium transfer in these environments and to keep sharing data in order to refine our predictive understanding of radiocesium mobility and consolidate the tools available to model contaminant transfer in ecosystems. In forests in particular, novel countermeasures and wood uses remain to be developed and tested. Furthermore, the hydrologic connectivity between soils under different ecosystems greatly influences long-term radiocesium transport. The consequences of extreme phenomena (e.g. typhoons, forest fires) that may become more frequent in the future as a result of global change in these contaminated environments should be further anticipated.

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Lestaevel, P., C. Huet, V. Lejeune, C. Moreno, C. Villagrasa, J. Feuardent i F. Trompier. "Cosmic radiation exposure of airline crews in France over the period 2015–2019". Radioprotection 58, nr 4 (październik 2023): 317–25. http://dx.doi.org/10.1051/radiopro/2023027.

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Cosmic particle flux increases with latitude and altitude and is significantly higher on-board aircraft than at ground level. Furthermore, its intensity depends on solar activity and eruptions. Due to their professional activity, flight crews (FCs) may receive an annual dose of some millisieverts. Therefore, the European directive adopted in 1996 requires the aircraft operators to assess the dose. The effective dose is to be estimated using various experimental and calculation means. In France, it is carried out by the computerized system for flight assessment of exposure to cosmic radiation SIEVERTPN, which sends to SISERI, the national dose registry, the monthly effective dose of each crew member. The average annual effective dose of French FCs was 2.19 mSv in 2019, i.e. between the standard permissible limits set for the public and the limit set for occupationally exposed persons. The effective dose received by the most exposed French FCs increased during the period 2015–2019 and that could be due to the solar cycle effect, changes in the staff flight time or the aircraft model. It can also be noted that more technical flight crews (TFCs) received a dose greater than 5 mSv over the 2016 to 2019 period than commercial flight crew (CFCs). Our study indicates that the number of FCs having received a dose greater than 5 mSv also increased over the period 2016 to 2019. Some parameters, that may affect the assessment of the aircrew effective dose, are not considered in SIEVERTPN calculations, as for example the Forbush decreases and the location in the plane. Lastly, several factors lead us to expect a decrease in the doses received by French aircrew staff in the coming years, such as the peak activity of the 25th eleven-year solar cycle expected in July 2025. However, some unexpected events, as for instance the war in Ukraine, can alter this prediction.

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32

Alam, AHM Zahirul. "Editorial". IIUM Engineering Journal 19, nr 1 (1.06.2018): i—iv. http://dx.doi.org/10.31436/iiumej.v19i1.917.

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IIUM ENGINEERING JOURNAL CHIEF EDITOR Ahmad Faris Ismail, IIUM, Malaysia TECHNICAL EDITOR Erry Yulian Triblas Adesta, IIUM, Malaysia EXECUTIVE EDITOR AHM Zahirul Alam, IIUM, Malaysia ASSOCIATE EDITOR Anis Nurashikin Nordin, IIUM, Malaysia LANGUAGE EDITOR Lynn Mason, Malaysia COPY EDITOR Hamzah Mohd. Salleh, IIUM, Malaysia EDITORIAL BOARD MEMBERS Abdullah Al-Mamun, IIUM, Malaysia Abdumalik Rakhimov, IIUM, Malaysia Amir Akramin Shafie, IIUM, Malaysia Erwin Sulaeman, IIUM, Malaysia Hanafy Omar, Saudi Arabia Hazleen Anuar, IIUM, Malaysia Konstantin Khanin, University of Toronto, Canada Ma'an Al-Khatib, IIUM, Malaysia Md Zahangir Alam, IIUM, Malaysia Meftah Hrairi, IIUM, Malaysia Mohamed B. Trabia, United States Mohammad S. Alam, Texas A&M University-Kingsville, United States Muataz Hazza Faizi Al Hazza, IIUM, Malaysia Mustafizur Rahman, National University Singapore, Singapore Nor Farahidah Binti Za'bah, IIUM, Malaysia Ossama Abdulkhalik, Michigan Technological University, United States Rosminazuin AB. Rahim, IIUM, Malaysia Waqar Asrar, IIUM, Malaysia AIMS & SCOPE OF IIUMENGINEERING JOURNAL The IIUM Engineering Journal, published biannually, is a carefully refereed international publication of International Islamic University Malaysia (IIUM). Contributions of high technical merit within the span of engineering disciplines; covering the main areas of engineering: Electrical and Computer Engineering; Mechanical and Manufacturing Engineering; Automation and Mechatronics Engineering; Material and Chemical Engineering; Environmental and Civil Engineering; Biotechnology and Bioengineering; Engineering Mathematics and Physics; and Computer Science and Information Technology are considered for publication in this journal. Contributions from other areas of Engineering and Applied Science are also welcomed. The IIUM Engineering Journal publishes contributions under Regular papers, Invited review papers, Short communications, Technical notes, and Letters to the editor (no page charge). Book reviews, reports of and/or call for papers of conferences, symposia and meetings, and advances in research equipment could also be published in IIUM Engineering Journal with minimum charges. REFEREESâ€™ NETWORK All papers submitted to IIUM Engineering Journal will be subjected to a rigorous reviewing process through a worldwide network of specialized and competent referees. Each accepted paper should have at least two positive refereesâ€™ assessments. SUBMISSION OF A MANUSCRIPT <![if !vml]><![endif]>A manuscript should be submitted online to the IIUM-Engineering Journal website: http://journals.iium.edu.my/ejournal. Further correspondence on the status of the paper could be done through the journal website and the e-mail addresses of the Executive Editor: zahirulalam@iium.edu.my Faculty of Engineering, International Islamic University Malaysia (IIUM), Jan Gombak, 53100, Kuala Lumpur, Malaysia. Phone: (603) 6196 4529, Fax:(603) 6196 4488. INTERNATIONAL ADVISORY COMMITTEE A. Anwar, United States Abdul Latif Bin Ahmad, Malaysia Farzad Ismail, USM, Pulau Pinang, Malaysia Hanafy Omar, Saudi Arabia Hany Ammar, United States Idris Mohammed Bugaje, Nigeria K.B. Ramachandran, India Kunzu Abdella, Canada Luis Le Moyne, ISAT, University of Burgundy, France M Mujtaba, United Kingdom Mohamed AI-Rubei, Ireland Mohamed B Trabia, United States Mohammad S. Alam, Texas A&M University-Kingsville, United States Nazmul Karim Ossama Abdulkhalik, Michigan Technological University, United States Razi Nalim, IUPUI, Indianapolis, Indiana, United States Syed Kamrul Islam, United States Tibor Czigany, Budapest University of Technology and Economics, Hungary Yiu-Wing Mai, The University of Sydney, Australia. Published by: IIUM Press, International Islamic University Malaysia Jalan Gombak, 53100 Kuala Lumpur, Malaysia Phone (+603) 6196-5014, Fax: (+603) 6196-6298 Website: http://iiumpress.iium.edu.my/bookshop Whilst every effort is made by the publisher and editorial board to see that no inaccurate or misleading data, opinion or statement appears in this Journal, they wish to make it clear that the data and opinions appearing in the articles and advertisement herein are the responsibility of the contributor or advertiser concerned. Accordingly, the publisher and the editorial committee accept no liability whatsoever for the consequence of any such inaccurate or misleading data, opinion or statement. IIUM Engineering Journal ISSN: 1511-788X E-ISSN: 2289-7860 Volume 19, Issue 1, June 2018 https://doi.org/10.31436/iiumej.v19i1 Table of Content CHEMICAL AND BIOTECHNOLOGY ENGINEERING ADSORPTION OF HEAVY METALS AND RESIDUAL OIL FROM PALM OIL MILL EFFLUENT USING A NOVEL ADSORBENT OF ALGINATE AND MANGROVE COMPOSITE BEADS COATED WITH CHITOSAN IN A PACKED BED COLUMN... 1 Rana Jaafar Jawad, Mohd Halim Shah Ismail, Shamsul Izhar Siajam INVESTIGATION OF BIOFLOCCULANT AS DEWATERING AID IN SLUDGE TREATMENT........................................ 15 Mohammed Saedi Jami, Maizirwan Mel, Aysha Ralliya Mohd Ariff, Qabas Marwan Abdulazeez HYDROGEN PRODUCTION FROM ETHANOL DRY REFORMING OVER LANTHANIA-PROMOTED CO/AL2O3 CATALYST............................. 24 Fahim Fayaz, Nguyen Thi Anh Nga, Thong Le Minh Pham, Huong Thi Danh, Bawadi Abdullah, Herma Dina Setiabudi, Dai-Viet Nguyen Vo OPTIMIZATION OF RED PIGMENT PRODUCTION BY MONASCUS PURPUREUS FTC 5356 USING RESPONSE SURFACE METHODOLOGY......................................................... 34 Nor Farhana Hamid And Farhan Mohd Said PRODUCTION AND STABILITY OF MYCO-FLOCCULANTS FROM LENTINUS SQUARROSULUS RWF5 AND SIMPLICILLIUM OBCLAVATUM RWF6 FOR REDUCTION OF WATER TURBIDITY.............................................................................. 48 Nessa Jebun, Md. Zahangir Alam, Abdullah Al-Mamun, Raha Ahmad Raus ROLE OF SUBSTRATE BINDING ON THE PROTEIN DYNAMICS OF AN ENDOGLUCANASE FROM FUSARIUM OXYSPORUM AT DIFFERENT TEMPERATURES .............................................................307 Abdul Aziz Ahmad, Ibrahim Ali Noorbatcha, Hamzah Mohd. Salleh CIVIL AND ENVIRONMENTAL ENGINEERING DIMINISHING SEISMIC EFFECT ON BUILDINGS USING BEARING ISOLATION....................................................... 59 A. B. M. Saiful Islam ELECTRICAL, COMPUTER AND COMMUNICATIONS ENGINEERING A DISTRIBUTED ENERGY EFFICIENT CLUSTERING ALGORITHM FOR DATA AGGREGATION IN WIRELESS SENSOR NETWORKS.................................................................................. 72 Seyed Mohammad Bagher Musavi Shirazi, Maryam Sabet, Mohammad Reza Pajoohan POWER QUALITY IMPROVEMENT WITH CASCADED MULTILEVEL CONVERTER BASED STATCOM................. 91 Mahdi Heidari, Abdonnabi Kovsarian, S. Ghodratollah Seifossadat THE EFFECTS OF CABLE CHARACTERISTICS ON MAXIMUM OVERVOLTAGE IN COMBINED OVERHEAD/CABLE LINES PROTECTED BY SURGE ARRESTERS.............................................................................. 104 Reza Alizadeh, Mohammad Mirzaie SMART PORTABLE CRYOTHERAPY SYSTEM REPHRASED I.E. WITH CONTROLLED THERMOELECTRIC COOLING MODULES FOR MEDICAL APPLICATIONS................................................................................................ 117 Abbas Rahmani, Reza Hassanzadeh Pack Rezaee, Naser Kordani STATIC PIPELINE NETWORK PERFORMANCE OPTIMISATION USING DUAL INTERLEAVE ROUTING ALGORITHM 129 Siva Kumar Subramaniam1, Shariq Mahmood Khan, Anhar Titik, Rajagopal Nilavalan A MODIFIED MODEL BASED ON FLOWER POLLINATION ALGORITHM AND K-NEAREST NEIGHBOR FOR DIAGNOSING DISEASES........................................................................ 144 Mehdi Zekriyapanah Gashti A SINGLE LC TANK BASED ACTIVE VOLTAGE BALANCING CIRCUIT FOR BATTERY MANAGEMENT SYSTEM .158 A K M Ahasan Habib, S. M. A. Motakabber, Muhammad Ibn. Ibrahimy, A. H. M. Zahirul Alam ENGINEERING MATHEMATICS AND APPLIED SCIENCE ON THE CONTROL OF HEAT CONDUCTION.......................................... 168 Fayziev Yusuf Ergashevich MATERIALS AND MANUFACTURING ENGINEERING GREEN SYNTHESIS OF SILVER NANOPARTICLES USING SAGO (METROXYLON SAGU) VIA AUTOCLAVING METHOD......178 Aliyah Jamaludin, Che Ku Mohammad Faizal EFFECT OF ALKALINE TREATMENT ON PROPERTIES OF RATTAN WASTE AND FABRICATED BINDERLESS PARTICLEBOARD....185 Zuraida Ahmad, Maisarah Tajuddin, Nurul Farhana Fatin Salim, Zahurin Halim AMORPHOUS STRUCTURE IN CU-ZN-V-AL OXIDE COMPOSITE CATALYST FOR METHANOL REFORMING..... 197 Mohd Sabri Mahmud, Zahira Yaakob, Abu Bakar Mohamad, Wan Ramli Wan Daud, Vo Nguyen Dai Viet PERFORMANCE OF ELECTRICAL DISCHARGE MACHINING (EDM) WITH NICKEL ADDED DIELECTRIC FLUID....215 Ahsan Ali Khan, Muataz Hazza Faizi Al Hazza, A K M Mohiuddin, Nurfatihah Abdul Fattah, Mohd Radzi Che Daud ENVIRONMENTAL DEGRADATION OF DURIAN SKIN NANOFIBRE BIOCOMPOSITE.......................................... 233 Siti Nur Eâ€™zzati Mohd Apandi, Hazleen Anuar, Siti Munirah Salimah Abdul Rashid MECHANICAL AND AEROSPACE ENGINEERING A REVIEW ON RHEOLOGY OF NON-NEWTONIAN PROPERTIES OF BLOOD....................................................... 237 Esmaeel Fatahian, Naser Kordani, Hossein Fatahian NUMERICAL STUDY OF THERMAL CHARACTERISTICS OF FUEL OIL-ALUMINA AND WATER-.......................... 250 Hossein Fatahian, Hesamoddin Salarian, Majid Eshagh Nimvari, Esmaeel Fatahian A PARAMETRIC STUDY ON CONTROL OF FLOW SEPARATION OVER AN AIRFOIL IN INCOMPRESSIBLE REGIME....270 Lakshmanan Prabhu, Jonnalagadda Srinivas OPTIMIZATION OF BOX TYPE GIRDER WITH AND WITHOUT INDUSTRIAL CONSTRAINTS................................ 289 Muhammad Abid, Shahbaz Mahmood Khan, Hafiz Abdul Wajid

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Augusto, Fabio. "Teaching Experimental Instrumental Analytical Chemistry Are we forming professionals, training operators or illuding students (and ourselves)?" Brazilian Journal of Analytical Chemistry 11, nr 43 (2.04.2024): 11–14. http://dx.doi.org/10.30744/brjac.2179-3425.point-of-view-faugusto.n43.

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The term “science” refers to “any system of knowledge that is concerned with the physical world and its phenomena and that entails unbiased observations and systematic experimentation”.1 Therefore, laboratory courses are almost universally considered an integral and mandatory part of instruction on science and technology,2 whatever the field or area of specialization. Consequently, undergraduate chemistry courses (and correlated specialties such as pharmaceutical sciences, biochemistry and some branches of engineering) always include practical disciplines, one of which is instrumental analytical chemistry. Despite being essential for these courses and part of the everyday routine of the faculty affiliated with analytical chemistry departments or programs, several aspects are far from being consensus among lecturers, students and the other people involved. Topics related to course syllabus, general approaches on the implementation and teaching of specific analytical techniques and experiments, their integration with other disciplines, and much more, are a matter of constant discussion and debate. One aspect to be considered is the considerable change in the profile of students that has occurred in recent years. The teaching tools and didactic approaches that university professors and instructors aged > 40 years experienced in their own training are generally not suitable for the present-day undergraduate audience. With former generations, the usual sources of information were printed books and similar materials available in libraries, whereas students today have a greater affinity for consulting online sources,3 which are not always reliable and often return a huge number of search results that require careful evaluation to select which information is relevant and/or reliable. Of course, the facility with which online sources of information are manipulated by our present pupils also has some important advantages: in particular, the near-instantaneous speed of information collection and the virtual accessibility to databases from anywhere on the planet. In addition, until the turn of the millennium, university students were more used to long lectures and experimental classes with relatively complex procedures that often took hours of careful manipulation and numerous laboratory operations (many of them repetitive and tedious). Specifically in the case of practical classes, many of today's students are relatively unaccustomed to experiments that require more than moderate manual skills (at least when compared to their colleagues of previous generations), which may also imply difficulty in organizing their time in the laboratory. Perhaps one of the biggest mistakes we make with our current students is that we consider them ill-prepared or less capable than our generation and attribute their difficulties to this simplistic, crude verdict – when perhaps the biggest problem is that, as educators, we are failing to cope with the rapid evolution in the characteristics and profiles of these young people. The type of change we need so that we can offer practical courses on instrumental analytical chemistry that are more appropriate and better suited for our students is not easy because, in addition to the demand that we change the vision of teaching and paradigms that we have considered as absolute since we entered our academic career, we are also confronted with practical reasons that make this type of change difficult. Laboratory classes demand a huge endeavor from technical and instructional staff and teaching assistants; furthermore, they are comparatively expensive, requiring space, fragile glassware, acquisition and maintenance of instruments, proper disposal of consumables and waste, as well as expenses on faculty salaries.4 The revision of curricula and experimental procedures would impose additional pressure on the workload of the personnel involved and also on the reduced budget availability typical of most public and private universities and colleges (whether in Brazil or anywhere else on the planet). Although there is no easy, direct and universal solution to the problems mentioned above, some alternatives can be tested and adopted with relative ease in most higher education courses on instrumental analytical chemistry. The workload of the experiments can be reduced, supplementing them or eventually even replacing some with practices carried out in virtual environments, which had an unexpected but necessary boost during the recent COVID-19 pandemic.5 Several paid or free-to-use tools have been described for this purpose. For instance, Shallice et al.6 describe a downloadable high-performance liquid chromatography simulator that emulates a basic automated liquid chromatography system capable of binary gradient operation. Similar software emulating other instrumental techniques exist, such as UV-Vis’s spectrometry, electroanalytical techniques, etc., as stand-alone applications, full online resources or even as Excel spreadsheets. In addition to simulated experiments using virtual analytical instruments, other resources that can be used as a supplement to practical instrumental analysis classes are online video libraries, which have also proliferated after the recent period of restriction on face-to-face activities. A well-known example is the collection of the Royal Chemical Society,7 which offers videos demonstrating basic principles and practical aspects of various instrumental techniques (from gas and liquid chromatography to nuclear magnetic resonance spectroscopy). In addition to possible inadequacies due to changes in the profile of typical students currently entering higher education courses in chemistry and related sciences, the evolution of analytical instrumentation, its scope of application and the practical demands imposed on analytical methods that future professionals will apply also pressure us to make changes in the programs of experimental disciplines of instrumental analytical chemistry and in the way we teach the associated techniques. Until the turn of the millennium, the typical program of experimental disciplines of instrumental analytical chemistry in most of the curricula in Brazil and many other countries comprised sequences of isolated experiments using analytical techniques such as gas or liquid chromatography, UV-Vis absorption spectrometry, atomic emission/emission spectrophotometry, etc., with samples and procedures that required relatively simple and quick preparation (usually only sample dissolution, decomposition or extraction). However, due to the natural evolution of analytical instrumentation, the equipment that future professionals will typically find in academic and industrial research laboratories after their impending graduation is very different from that previously employed in the teaching laboratories where their instructors learned analytical chemistry (typically, much simpler equipment that required careful attention and reasonable practical skills from users and operators). The contemporary analytical instruments are much less transparent to the user in their operation; however, as a rule, they incorporate extensive automation and/or mechanization resources, complete control of operation by software and greater operational robustness. From a didactic point of view, modern equipment certainly does not provide students with the same understanding and insight of the basic operational principles of the associated techniques as the instruments of previous generations. However, considering the typical profile of today's students, it possibly would not be advantageous to use those simpler analytical platforms exhaustively merely for didactic purposes. For example, until the turn of the millennium, one of the main demands for students in gas chromatography didactic experiments was to improve and master the manual injection of samples using micro syringes. Today, this didactic approach seems to be preposterous, considering that chromatographs without automatic sample injection are becoming increasingly rare in industrial and even in academic environments. The result is that students are sometimes subjected to tedious laboratory sessions and often completely lose their focus on what would be fundamental in that practical class. In addition, the present demand is increasingly for professionals to be trained to interpret data and propose solutions based on the information gained and not to act as mere operators of laboratory equipment. Thus, it seems to us that we should increasingly design experiments for undergraduate students that incorporate all stages of the analytical process, with particular attention to sampling and sample preparation (taking advantage of features of modern instruments that allow processing more samples in less time and whose operation is less dependent of user ability and manual dexterity) as well as the interpretation and understanding of the analytical data produced. Regarding the above-mentioned focus on the interpretation and understanding of analytical data, it is interesting to note that in 2004, when the Analytical Chemistry Division of the Federation of European Chemical Societies (FECS) established the curricular guidelines to be observed in the analytical chemistry disciplines taught in universities of the European Community (the so-called "Eurocurriculum II"),8 four basic pillars of education in analytical chemistry were defined: Spectroscopy; Chromatography; Chemical Sensors; and Chemometrics and Computer-Based Analytical Chemistry. Thus, it was recognized that in modern analytical chemistry the processing and interpretation of data, as well as its transformation into useful information about the chemical systems studied, is on a par with the three traditional subdivisions of analytical chemistry (spectroscopic and spectrometric techniques, chromatographic techniques and electroanalytical techniques). Although it is important to emphasize that these considerations apply to courses in the European Community, they can be contemplated in the training of chemists anywhere else on the world. Also, they reinforce the indication that the education of analytical chemists should place an increasing emphasis on aspects related to information generation/manipulation and interpretation and not merely on the direct operational aspects of analytical methods and protocols already established. The discussion so far does not pretend to cover all the relevant points whose evaluation would perhaps be necessary for a comprehensive and exhaustive debate of the current status of college/University courses on instrumental analytical chemistry, as well as the possible alternatives and paths to follow. In addition, this text of course echoes the author’s personal opinions and idiosyncrasies, without any pretense at being an absolute expression of the truth (if indeed one exists on this matter). In fact, any discussion of these topics is, by their nature, highly controversial and heavily influenced by the background and area of expertise of those involved. However, we have the firm conviction that the community needs to continuously discuss the education and professional development in analytical chemistry, with emphasis on areas where changes can occur very quickly, always keeping an open mind and a willingness to review supposedly untouchable concepts (and, of course, remembering that its focus should always be on the students).

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Apted, Michael, i Kjell Andersson. "Technical Workshop on Near-Field Performance Assessment of High-Level Waste Disposal". MRS Proceedings 333 (1993). http://dx.doi.org/10.1557/proc-333-775.

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ABSTRACTAn international Workshop was conducted to discuss the present state of modelling of near-field performance of high-level waste repositories, with emphasis on the conceptual and mathematical models for source-term calculations. The Workshop was based on an international survey and review of this topic by the authors. Technical position papers developed by the participants are summarized here. A Proceedings of the Workshop, including the full position papers and the survey and review document, are to be published by Nuclear Energy Agency by the end of 1993.

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Bullen, Daniel B., Gregory E. Gdowski i R. Daniel McCright. "Impact of Phase Stability on the Corrosion Behavior of the Austenitic Candidate Materials For NNSWI." MRS Proceedings 112 (1987). http://dx.doi.org/10.1557/proc-112-793.

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AbstractThe Nuclear Waste Management Program at Lawrence Livermore National Laboratory is responsible for the development of the waste package design to meet the Nuclear Regulatory Commission licensing requirements for the Nevada Nuclear Waste Storage Investigations (NNWSI) Project. The metallic container component of the waste package is required to assist in providing substantially complete containment of the waste for a period of up to 1000 years. Long term phase stability of the austenitic candidate materials (304L and 316L stainless steels and alloy 825) over this time period at moderate temperatures (100–250°C) can impact the mechanical and corrosion behavior of the metal barrier.A review of the technical literature with respect to phase stability of 304L, 316L and 825 is presented. The impact of martensitic transformations, carbide precipitation and intermediate (σ. χ, and η) phase formation on the mechanical properties and corrosion behavior of these alloys at repository relevant conditions is discussed. The effect of sensitization on intergranular stress corrosion cracking (IGSCC) of each alloy is also addressed. A summary of the impact of phase stability on the degradation of each alloy in the proposed repository environment is included.

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Esh, David W., Anna H. Bradford, Kristina L. Banovac i B. Jennifer Davis. "Risks and Uncertainties Associated With High-Level Waste Tank Closure". MRS Proceedings 757 (2002). http://dx.doi.org/10.1557/proc-757-ii1.12.

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ABSTRACTClosure of tanks containing high-level radioactive waste (HLW) is a challenging problem involving potentially competing influences from economic, societal, and technological considerations. The U.S. Department of Energy (DOE) is faced with protecting public health and the environment while making economically responsible decisions. Risk (i.e., annual dose) is becoming more prominent as DOE's metric to evaluate the economic consequences of its decisions. Risks are assessed through modeling and calculations commonly known as performance assessment (PA). In the process of tank closure, the U.S. Nuclear Regulatory Commission (NRC) is typically consulted to perform an independent review of DOE's PAs.The NRC staff developed a generic PA model, applicable to HLW tank closure, which NRC utilizes to complete its independent review. The model was developed using the generic simulation software, GoldSim, because of its probabilistic capabilities and its adaptability to different problems [1]. The NRC staff uses the resultant risk from the generic models to evaluate the reasonableness of performance assessment models submitted by DOE. Large differences in the estimates of risk between the generic PA model and the DOE PA would likely indicate a need for stronger technical basis for processes significantly contributing to annual dose (risk) reduction.

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37

Cherry, Debra, Elizabeth Friedman, Melissa Vincent i Andrew Maier. "The legacy of weapons grade plutonium production: Health status of Hanford complex workers who manage the waste". Toxicology and Industrial Health, 15.04.2021, 074823372199655. http://dx.doi.org/10.1177/0748233721996555.

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The extent and etiology of health effects in workers who maintain underground storage tanks at the Hanford Nuclear Reservation (Hanford) have been subjects of controversy and concern for several decades. Hanford is a decommissioned nuclear production complex managed by the US Department of Energy in southeast Washington State. This integration-of-evidence review evaluates the relationship between exposure to vapors from mixed chemical and radioactive waste stored in underground storage tanks at Hanford and worker health. Hanford workers’ health information was gathered from technical reports, media reports, and published literature, including the systematic search of seven databases. This review describes the health status and health concerns of Hanford tank farm workers based on the integration of the available health effects data from disparate sources. In interviews with external groups, Hanford workers reported both irritant-type symptoms and diseases that they believe are attributable to tank farm vapors. However, the results of this integration-of-evidence review indicated that no pervasive pattern of occupational disease was identified that can be associated with exposure to tank farm vapors. Inhalation exposure to asbestos and beryllium is associated with lung disease from various types of nuclear industry work but not from work on tank farms. This review concluded that while irritant-type symptoms and isolated cases of occupational disease are plausible under certain conditions, the currently available data do not support a pervasive pattern of occupational disease associated with vapor exposure.

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38

Gupta, Amit, Priyanka Naranje, Zainab Vora, Raju Sharma, Manisha Jana, Ashu Seith Bhalla, Pallavi Sinha i in. "Intranodal lipiodol injection for the treatment of chyle leak in children – A Preliminary experience". British Journal of Radiology, 20.07.2022. http://dx.doi.org/10.1259/bjr.20211270.

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Objective: To assess the effectiveness of intranodal lymphangiography using ethiodized oil (Lipiodol; Guerbet Japan, Tokyo, Japan) for the treatment of refractory cases of chylothorax and chylous ascites in the pediatric population. Methods: Between 2016 and 2020, eight children having chyle leak resistant to conservative management underwent intranodal lymphangiography using lipiodol injection. After ethical approval by the Institutional Review Board, these patients’ data was retrospectively analysed. Technical success was defined by opacification of inguinal and retroperitoneal lymphatics while injection on fluoroscopy. Clinical success was defined as progressively decreasing drain output and eventual cessation of output within a week after the procedure. Long-term follow up was done as feasible. Results: Technical success was achieved in all the patients. Complete cessation of drain output was noted within 1 week of procedure in all patients indicating clinical success. One patient had recurrence of chylous leakage after an interval of 1 month and intranodal lymphangiography was repeated for that patient. The child had technical as well as clinical success after the repeat procedure. Hence a total of 9 procedures were performed in 8 patients. Conclusion: Intranodal lymphangiography may prove to be a valuable minimally invasive therapeutic tool in cases of refractory chylous leakage in pediatric patients with minimal risk of complications. Advances in knowledge: Intranodal lymphangiography using lipiodol may prove to be a minimally invasive alternative in pediatric patients with refractory lymphatic leaks.

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"Resource-saving and environmental protection in nuclear-grade zirconium and hafnium production". Geo-Technical Mechanics, nr 164 (2023): 135–49. http://dx.doi.org/10.15407/geotm2023.164.135.

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The development of efficient and environmentally friendly technological processes for processing zircon concentrate is an urgent problem in the technology of producing reactor-pure zirconium and hafnium used in nuclear power. The review presents the environmental, technical and economic characteristics of zircon decomposition processes using existing industrial technologies and provides data on the environmental safety of each technology. It is shown that current industrial technologies do not meet the criteria of sustainable development and allow emissions of toxic reagents into the environment. New applications of particularly pure zirconium and hafnium compounds which have emerged in recent decades, with impurity content of 10-3–10-5%, require less corrosive reagents than chlorine and fluorine, new resource-saving processes and equipment. Today, technical zirconium oxide with a purity of 98% is the main industrial product of zircon processing, but it allows for losses of hafnium, scandium and silicon. This is equivalent to financial losses of over USD 150 million per year. Based on the analysis of promising halogen-free technologies, a new integrated zircon processing technology is proposed which allows producing scarce hafnium, scandium and silicon compounds along with reactor-pure zirconium and its high-purity chemical compounds. The chemicals consumed in the zircon processing process are utilized in the production of mineral fertilizers, eliminating environmental pollution. The use of the highly efficient refining extraction process in a nitric acid environment using centrifugal extractors with an available tributilphosphate extractant allows us to obtain reactor metals with a purity of 99.95%. The production of high-purity zirconium, hafnium, scandium and silicon oxides meets the demand for non-nuclear products, which expands the volume of integrated zircon processing and meets the growing market demand for new functional materials. The integrated approach to zircon processing can reduce the cost of zircon by producing by-products, recycling consumed reagents and eliminating non-recyclable solid and liquid waste. This will ensure environmental protection even with relatively small volumes of reactor-pure metal production.

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Zauer, E. A. "Modern instrumentation and practical application of flame atomic emission spectrometry". Chimica Techno Acta 11, nr 1 (4.03.2024). http://dx.doi.org/10.15826/chimtech.2024.11.1.09.

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The modern instrumentation for flame atomic emission spectrometry (FAES) is overviewed: the main technical (composition of the fuel gas used, dispersing element, number of analytical channels, reference channel, detecting element, sampling method) and analytical (determined elements, range of determined concentrations, limits and the accuracy of their determination, the duration of a single measurement, the equired amount of the analyzed sample) characteristics of flame photometers for industrial and clinical use as well as spectrophotometers currently made by various manufacturers such as Sherwood Scientific Ltd., BWB Technologies UK Ltd., Labtron Equipment Ltd., Labnics Equipment Ltd. and JENWAY Ltd (UK); A.KRÜSS Optronic (Germany); Cole Parmer Instrument Company and Labfon Equipment Inc. (USA); Inesa Analytical Instrument Co., Ltd (China); OJSC Zagorsk Optical and Mechanical Plant, Unico-SIS LLC and VMK-Optoelectronics LLC (Russia); Manti Lab Solutions, Labtronics, Systonic, Globe Instruments, Electronics India, Lasany (India). The main areas of application of FAES are presented – bioenergy, agriculture (analysis of plants, soil extracts and fertilizers), mineral raw materials (geology), clinical medicine and pharmaceuticals, food industry, environmental control (analysis of drinking, technical and waste water), nuclear energy, metallurgy and chemical industry, as well as some features and problems associated with the preparation of samples for analysis by the FAES method. The review includes references to works on the practical application of FAES, published mainly from 1998 to 2023.

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Vimala, Leena Robinson, Diego Andre Eifer, Yasser Karimzad i Narinder S. Paul. "Prospective Clinical Trial Comparing IV Esmolol to IV Metoprolol in CT Coronary Angiography: Effect on Hemodynamic, Technical Parameters and Cost". Canadian Association of Radiologists Journal, 22.07.2021, 084653712110239. http://dx.doi.org/10.1177/08465371211023947.

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Background: Intravenous [IV] esmolol, an alternative to IV metoprolol for coronary computed tomography angiography [CCTA], has shorter half-life that decreases the risk of prolonged hypotension. The primary aim was to prospectively compare IV esmolol alone to IV metoprolol alone for effectiveness in achieving heart rate [HR] of 60 beats per minute[bpm] during CCTA. The secondary aim was to compare hemodynamic response, image quality, radiation dose and cost. Materials and Methods: Institutional Review Board approved prospective randomized study of 28 CCTA patients medicated in a 1:1 blinded match with IV esmolol or IV metoprolol to achieve HR of 60 bpm. Serial hemodynamic response was measured at 6 specified times. Two cardiac radiologists independently scored the image quality. Results: Both IV esmolol and IV metoprolol achieved the target HR. IV esmolol resulted in significantly less profound and shorter duration of reduction in systolic blood pressure [BP] than IV metoprolol with a difference of -10, -14 and -9 mm Hg compared to -20, -26 and -25 mmHg at 2, 15 & 30 min respectively. No significant difference in HR at image acquisition, exposure window, radiation dose and image quality. Although IV esmolol was expensive, the overall cost of care was comparable to IV metoprolol due to shortened post CCTA observation period consequent to faster restoration of hemodynamic status. Conclusion: Comparison of IV esmolol and IV metoprolol demonstrate that both are effective in achieving the target HR but significantly faster recovery of HR and BP in patients who receive IV esmolol was found.

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Sivalingam, Kalpana, Karthik Palanisamy i Amalan Ignatius. "Management of Visceral Artery Pseudoaneurysms by Combined Technique of Percutaneous Thrombin Injection and Endovascular Coiling". Journal of Clinical Interventional Radiology ISVIR, 1.06.2021. http://dx.doi.org/10.1055/s-0041-1728977.

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Abstract Purpose To describe our initial experience with percutaneous thrombin injection combined with endovascular coiling of high-flow visceral artery pseudoaneurysms. Materials and Methods Institutional review board approval was obtained. Between January 2019 and February 2020, 21 patients with nonvariceal upper gastrointestinal (GI) bleed underwent multidetector CT angiography. Four patients with acute pancreatitis and large pseudoaneurysms were selected for the combined technique. Human thrombin reconstituted with calcium chloride was injected percutaneously. Partially thrombosed aneurysms were treated up to three times. Simultaneously or within 15 days, coil embolization of the neck or patent part of pseudoaneurysm was performed. Patients were followed up to 1 month postprocedure. Results The size of the pseudoaneurysms ranged from 3 cm to 6 cm. All were accessed percutaneously by 22G Chiba needle under ultrasound guidance and 500 to 1500 units of thrombin was injected in one to three attempts. Subsequently, endovascular coiling of the neck of the pseudoaneurysm or of the feeding artery was performed. Technical success with cessation of flow was achieved in all four patients. One patient developed obstructive jaundice postprocedure and another continued to have GI bleeding despite thrombin injection. Conclusion Percutaneous thrombin injection is an easy to use and effective tool for treating visceral artery pseudoaneurysms and can be combined with endovascular coiling for successful occlusion of large pseudoaneurysms.

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Zhu, Ante, Matthew Tarasek, Yihe Hua, Eric Fiveland, Stephan E. Maier, Yousef Mazaheri, Maggie Fung i in. "Human prostate MRI at ultrahigh‐performance gradient: A feasibility study". Magnetic Resonance in Medicine, 27.09.2023. http://dx.doi.org/10.1002/mrm.29874.

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AbstractPurposeTo demonstrate the technical feasibility and the value of ultrahigh‐performance gradient in imaging the prostate in a 3T MRI system.MethodsIn this local institutional review board–approved study, prostate MRI was performed on 4 healthy men. Each subject was scanned in a prototype 3T MRI system with a 42‐cm inner‐diameter gradient coil that achieves a maximum gradient amplitude of 200 mT/m and slew rate of 500 T/m/s. PI‐RADS V2.1–compliant axial T2‐weighted anatomical imaging and single‐shot echo planar DWI at standard gradient of 70 mT/m and 150 T/m/s were obtained, followed by DWI at maximum performance (i.e., 200 mT/m and 500 T/m/s). In comparison to state‐of‐the‐art clinical whole‐body MRI systems, the high slew rate improved echo spacing from 1020 to 596 μs and, together with a high gradient amplitude for diffusion encoding, TE was reduced from 55 to 36 ms.ResultsIn all 4 subjects (waist circumference = 81–91 cm, age = 45–65 years), no peripheral nerve stimulation sensation was reported during DWI. Reduced image distortion in the posterior peripheral zone prostate gland and higher signal intensity, such as in the surrounding muscle of high‐gradient DWI, were noted.ConclusionHuman prostate MRI at simultaneously high gradient amplitude of 200 mT/m and slew rate of 500 T/m/s is feasible, demonstrating that improved gradient performance can address image distortion and T2 decay–induced SNR issues for in vivo prostate imaging.

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Koukounaras, Jim, Warren Clements, W. Catarina Ang, Adil Zia, Matthew Lukies, Heather K. Moriarty i Helen Kavnoudias. "A Prospective Pilot Study of the Safety and Effectiveness of Uterine Artery Embolization for the Treatment of Endometriosis: The UAE-E Study". Journal of Clinical Interventional Radiology ISVIR, 10.05.2023. http://dx.doi.org/10.1055/s-0043-1768942.

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Abstract Purpose Uterine artery embolization (UAE) evidence is increasing in the setting of adenomyosis, which shares pathological similarities to endometriosis. Endometriosis is characterized by the presence of endometrium-like tissue outside of the uterus, and the retrograde menstruation hypothesis may account for disease development. In women where fertility is no longer desired, hysterectomy can be offered to improve pain-related symptoms. The authors hypothesize that this cohort of patients may similarly respond to UAE. The aim of this pilot study is to assess the safety and effectiveness of UAE in the management of endometriosis-related symptoms. Methods Six-patient prospective single-arm pilot study in female, premenopausal patients over 40 years with symptoms of endometriosis. Institutional review board approval was obtained.Inclusion criteria include completed family, premenopausal, pelvic endometriosis as confirmed by laparoscopy within the last 5 years, and symptoms of endometriosis impacting quality of life as evidenced by the British Society of Gynaecological Endoscopy pelvic pain and Short Form-36 questionnaires. Results The primary endpoint will be safety, as assessed by the composite number of procedural and postprocedural complications during procedure, predischarge, and at 6 weeks, 3 months, 6 months, and 12 months. Secondary endpoints will include technical success, clinical success, and durability. Discussion This study will be a novel application of UAE in the setting of endometriosis and has the potential to improve patient quality of life. This pilot study will assess safety and allow the investigators to design a prospective randomized controlled study.

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Kim, Eun Ju, Chan Park, Seunghyeon Cho, Hyun Kyung Ryu, Jong Eun Lee, Hyoung Ook Kim i Byung Chan Lee. "Effectiveness of Uterine Arterial Embolization and Risk Factors Associated with Its Failure in Patients with Primary Postpartum Hemorrhage After Cesarean Section". Iranian Journal of Radiology 19, nr 4 (19.12.2022). http://dx.doi.org/10.5812/iranjradiol-128424.

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Background: Postpartum hemorrhage (PPH), a serious labor-related complication, is the leading cause of maternal mortality, which requires an emergent intervention. Uterine arterial embolization (UAE) is an effective treatment for hemostasis of intractable PPH. Several risk factors have been reported for the failure of UAE. Objectives: To evaluate the clinical outcomes of UAE for the treatment of primary PPH following cesarean section (CS) and to determine the risk factors associated with the failure of this procedure. Methods: This retrospective, single-center study was approved by the institutional review board, and the requirement to obtain informed consent was waived. All patients referred to a tertiary care center, who underwent UAE for primary PPH between January 2018 and December 2020, were included. The patients’ medical records and radiological findings, including the patients’ characteristics, mode of delivery, initial vital signs and laboratory findings after hospitalization, procedure details, and embolization outcomes, were evaluated for data collection. Technical success was defined as appropriate embolization of target vessels on a completion angiogram. Clinical success was defined as adequate cessation of bleeding after the first embolization, without any need for subsequent embolization or surgical intervention. Statistical analysis was performed to determine factors related to the clinical failure of UAE in CS cases. Results: UAE was performed for 25 patients (mean age, 37.2 years; range, 25 - 45 years). The technical success rate was estimated at 100% (n = 25), and the clinical success rate was 76% (n = 19). There were no patients with permanent adverse sequelae or death. The univariate analyses showed that hemodynamic instability (P = 0.006), lower hemoglobin levels (P = 0.02), and prolonged activated partial thromboplastin time (aPTT) (P = 0.017) were related to clinical failure. The logistic regression analysis adjusted for age showed that the area under the curve (AUC) was 0.86 for hemoglobin (95% CI: 0.7 - 1; cutoff value: 0.667), 0.816 for aPTT (95% CI: 0.625 - 1; cutoff value: 0.411), and 0.868 for hemodynamic instability (95% CI: 0.661 - 1; cutoff value: 0.622). Conclusions: UAE is a safe and effective treatment for primary PPH following CS. Hemodynamic instability, low hemoglobin levels, and prolonged aPTT can be predictive factors for the poor outcomes of UAE in CS patients. These factors are rapid and straightforward criteria, which can be simply applied, even in emergency situations.

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M, Athiyaman. "A short Review of the ALARA Principle in Radiation Protection". Open Access Journal of Cancer & Oncology 7, nr 1 (2023). http://dx.doi.org/10.23880/oajco-16000185.

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Any activity involving radiation should be planned and conducted in such a way that the exposures to individuals are optimally low, taking into consideration the economic and cost aspects. This principle of optimization is called ALARA. ALARA stands for “As Low as Reasonably Achievable”. The ALARA principle states that the radiation exposures should be limited to a minimum level since the Ionizing radiation may produce biological effects in the exposed person. Background of ALARA Concept: The introduction of ALARA was a great philosophical change, as instead of working up to the permissible exposure limits, the idea was to keep exposures to levels as far below the limits as could reasonably be done, considering economic and technical factors. The linear-no-threshold (LNT) model, labeled is the basis of the ALARA protocol; if even small doses lead to slight increases in the risk of cancer than doses should be kept as low as possible. The concept of ALARA was first introduced in 1954 in the National Council on Radiation Protection & Measurements (NCRP) Report, and later in International Commission on Radiological Protection (ICRP) Publication 1 where it was initially called ALAP, the acronym for As Low As Practicable (ICRP 1959b). As per Atomic Energy Regulatory Board (AERB), Govt of India, all radiation work should be carried out in a preplanned and controlled manner so that the exposure to the workers and persons in and near sites of radiation use is kept as low as reasonably achievable (ALARA) and does not exceed the recommended limits. Suitable control measures shall be employed to minimize radiation exposure so that maximum benefits are derived with minimum radiological risk. Discussion: The ALARA principle appears simple but is often misinterpreted and inappropriately applied in radiation protection. It is often interpreted as “as low as possible” without taking into consideration the balancing factors. Considering radiation shielding requirements as an example excessive unnecessary shielding with materials such as lead, steel, or concrete is a waste of global resources. This in turn can cause other damages such as chemical harm and pollution to the environment, which have proven damages to human health. It is more meaningful to make use of the wasted resources for service improvements, such as reducing the charges to patients, investing in better medical technologies, and training of staff. Conclusion: The aims of radiation protection are (i) to avoid the occurrence of deterministic effects and (ii) to limit the risk of stochastic effects. ALARA protocol has successfully limited the exposure of radiation workers to impressively low levels of dose around 1 mSv. Since significant costs are incurred to comply with ALARA and the validity of the LNT model is unclear below doses of 100 mSv, more research on the health effects of low radiation doses is necessary before alternatives to ALARA can become viable.

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Zhu, Hongcheng, Qiufang Liu, Hao Xu, Miao Mo, Zezhou Wang, Kui Lu, Jialiang Zhou i in. "Dose escalation based on 18F-FDG PET/CT response in definitive chemoradiotherapy of locally advanced esophageal squamous cell carcinoma: a phase III, open-label, randomized, controlled trial (ESO-Shanghai 12)". Radiation Oncology 17, nr 1 (29.07.2022). http://dx.doi.org/10.1186/s13014-022-02099-y.

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Abstract Introduction Definitive chemoradiotherapy has established the standard non-surgical treatment for locally advanced esophageal cancer. The standard dose of 50–50.4 Gy has been established decades ago and been confirmed in modern trials. The theorical advantage of better local control and technical advances for less toxicity have encouraged clinicians for dose escalation investigation. 18F-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) have the potential to tailor therapy for esophageal patients not showing response to CRT and pioneers the PET-based dose escalation. Methods and analysis The ESO-Shanghai 12 trial is a prospective multicenter randomized phase 3 study in which patients are randomized to either 61.2 Gy or 50.4 Gy of radiation dose by PET response. Both groups undergo concurrent chemoradiotherapy with paclitaxel/cisplatin regimen for 2 cycles followed by consolidation chemotherapy for 2 cycles. Patients with histologically confirmed ESCC [T1N1-3M0, T2-4NxM0, TxNxM1 (Supraclavicular lymph node metastasis only), (AJCC Cancer Staging Manual, 8th Edition)] and without any prior treatment of chemotherapy, radiotherapy or surgery against esophageal cancer will be eligible. The primary endpoints included overall survival in PET/CT non-responders (SUVmax > 4.0) and overall survival in total population. Patients will be stratified by standardized uptake volume, gross tumor volume and tumor location. The enrollment could be ended, when the number of PET/CT non-responder reached 132 and the total population reached 646 for randomization. Ethics and dissemination This trial has been approved by the Fudan University Shanghai Cancer Center Institutional Review Board. Trial results will be disseminated via peer reviewed scientific journals and conference presentations. Trial registration The trial was initiated in 2018 and is currently recruiting patients. Trial registration number NCT03790553.

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Dreisbach, John G., Jonathan CL Rodrigues i Giles Roditi. "Emergency CT misdiagnosis in acute aortic syndrome". British Journal of Radiology, 7.09.2021, 20201294. http://dx.doi.org/10.1259/bjr.20201294.

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Objectives: This cross-sectional study assessed the accuracy of emergency CT reports at presentation in acute aortic syndrome (AAS). Methods: Retrospective identification of cases of AAS presenting within a large health board with three acute hospitals receiving adult patients between January 2013 and December 2016. CT studies and reports at presentation were reviewed for discrepancies related to diagnosis, complications and classification by two cardiovascular radiologists. The specialist interest of the original reporters, clinically suspected diagnosis at referral for CT and technical adequacy of the scans were also assessed. False-positive diagnoses were identified and evaluated separately. Results: Among 88 consecutive confirmed cases of AAS at least one discrepancy was identified in 31% (n = 27), including failure to identify or misinterpretation of the AAS itself in 15% (n = 13), haemorrhage in 13% (n = 11), branch involvement in 9% (n = 8), and misclassification in 3% (n = 3). All discrepancies occurred among the 80% (n = 70) of cases reported by radiologists without specialist cardiovascular interest. 26% (n = 23/88) of AAS cases were not clinically suspected at referral for CT and although this was associated with suboptimal protocols, only 51% of CT scans among suspected cases were technically adequate. Seven false-positive diagnoses were identified, three of which related to motion artefact. Conclusion: Significant discrepancies are common in the emergency CT assessment of positive cases AAS and this study highlights important pitfalls in CT technique and interpretation. The absence of discrepancies among radiologists with specialist cardiovascular interest suggests both suspected and confirmed cases warrant urgent specialist review. Advances in knowledge: CT angiography is central to the diagnosis of AAS; however, significant radiology discrepancies are common among non-specialists. This study highlights important pitfalls in both CT technique as well as interpretation and supports routine specialist cardiovascular imaging input in the emergency assessment of AAS.

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Kapsner, Lorenz A., Eva L. Balbach, Frederik B. Laun, Lukas Baumann, Sabine Ohlmeyer, Michael Uder, Sebastian Bickelhaupt i Evelyn Wenkel. "Prevalence and influencing factors for artifact development in breast MRI-derived maximum intensity projections". Acta Radiologica, 8.09.2023. http://dx.doi.org/10.1177/02841851231198349.

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Background Magnetic resonance imaging (MRI) provides high diagnostic sensitivity for breast cancer. However, MRI artifacts may impede the diagnostic assessment. This is particularly important when evaluating maximum intensity projections (MIPs), such as in abbreviated MRI (AB-MRI) protocols, because high image quality is desired as a result of fewer sequences being available to compensate for problems. Purpose To describe the prevalence of artifacts on dynamic contrast enhanced (DCE) MRI-derived MIPs and to investigate potentially associated attributes. Material and Methods For this institutional review board approved retrospective analysis, MIPs were generated from subtraction series and cropped to represent the left and right breasts as regions of interest. These images were labeled by three independent raters regarding the presence of MRI artifacts. MRI artifact prevalence and associations with patient characteristics and technical attributes were analyzed using descriptive statistics and generalized linear models (GLMMs). Results The study included 2524 examinations from 1794 patients (median age 50 years), performed on 1.5 and 3.0 Tesla MRI systems. Overall inter-rater agreement was kappa = 0.54. Prevalence of significant unilateral artifacts was 29.2% (736/2524), whereas bilateral artifacts were present in 37.8% (953/2524) of all examinations. According to the GLMM, artifacts were significantly positive associated with age (odds ratio [OR] = 1.52) and magnetic field strength (OR = 1.55), whereas a negative effect could be shown for body mass index (OR = 0.95). Conclusion MRI artifacts on DCE subtraction MIPs of the breast, as used in AB-MRI, are a relevant topic. Our results show that, besides the magnetic field strength, further associated attributes are patient age and body mass index, which can provide possible targets for artifact reduction.

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Zhao, Ying, Yangfan Cao, Wenchao Wang, Wei Qi, Maoyan Jing i Qun fan Sun. "Development of an Automatic Tree Coating Machine Based on Cooperative Functioning of Multiple Nozzles". Recent Patents on Engineering 17 (2.02.2023). http://dx.doi.org/10.2174/1872212117666230202142500.

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Background: At present, the tree whitewashing in China is mainly based on the traditional manual whitewashing method, which has the shortcomings of high labor intensity, low efficiency, excessive wastage of paint, danger to human health, and poor adaptability to the strong seasonality of tree whitewashing. background: At present, the traditional manual whitewashing method is used in tree whitewashing in China, which has the characteristics of high labor intensity, low efficiency, large waste of paint, endangering human health, and does not adapt to the strong seasonality of tree whitewashing. Objective: To reduce the sunburn and water evaporation of trees, prevent the invasion of diseases and pests, and to enhance the disease resistance of trees, the tree trunk coating mainly uses a traditional manual method. However, this mainstream manual whitewashing approach is labor- intensive and inefficient. To resolve the issue, an automatic spraying device for tree coating based on multi-sprinkler cooperative operation is designed. It can meet the requirements of tree whitening and replace manual operation. To some extent, this machine can reduce labor intensity and promote the healthy growth of trees. objective: An automatic spraying device for trees based on multi sprinkler cooperative operation is designed. It meets the requirements of tree whitening and can replace manual operation. Methods: Through literature review and field research, the technical requirements and research status of tree whitewashing have been explored. The three-dimensional Software Solidworks has been used to model the rack assembly, device moving assembly, up and down moving assembly, nozzle moving support assembly, and spraying assembly, and then the three-dimensional assembly of the whole machine has been carried out. According to the simulation optimization results, the initial three-dimensional model is modified, and then the engineering drawing is drawn through the three-dimensional model for prototype processing, manufacturing, and assembly. The schematic diagram and PCB pattern of the circuit board of the electronic control system have been drawn, the program of the controller k60dn512 single chip microcomputer has been written, simulation and debugging have been conducted, and the control system has been designed. Laboratory and field tests on the prototype have been conducted, and the device has been improved according to the test data. method: Through literature review and field research, understand the technical requirements and research status of tree whitewashing, and use the three-dimensional Software Solidworks to model the rack assembly, device moving assembly, up and down moving assembly, nozzle moving support assembly, and spraying assembly, and then carry out the three-dimensional assembly of the whole machine. According to the simulation optimization results, the initial three-dimensional model is modified, and then the engineering drawing is drawn through the three-dimensional model for prototype processing, manufacturing and assembly. Draw the schematic diagram and PCB pattern of the circuit board of the electronic control system, write the program of the controller k60dn512 single chip microcomputer, conduct simulation and debugging, and design the control system. Carry out laboratory and field tests on the prototype, and improve and perfect the device according to the test data. Results: Experiments show that the device can accurately spray trees with a trunk circumference of 50-125cm. When the trunk circumference is greater than 125cm, repeated spraying can meet the spraying requirements. The trunk circumference is in the range of 50-80cm, and the opening and closing angle is in the range of 80-100 °. The spraying effect is good, and the average spraying coverage can reach 97.73%. The trunk perimeter is in the range of 80-125cm, and the opening and closing angle is in the range of 100-120 °. The spraying effect is the best, and the average spraying coverage can reach 98.06%. During the experiment, the spraying efficiency of the device can reach 100 trees/hour, which is significantly higher than the efficiency of manual operation. Conclusion: The device improves the efficiency and quality of tree spraying, reduces the labor intensity of operation, and realizes the high-efficiency spraying for tree coating. conclusion: The device improves the efficiency and quality of tree spraying, reduces the labor intensity of operation, and realizes the high-efficiency spraying of trees through the embracing structure of copying trees.

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