78 FR 35056 - Effectiveness of the Reactor Oversight Process Baseline Inspection Program

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-11

... NUCLEAR REGULATORY COMMISSION [NRC-2013-0125] Effectiveness of the Reactor Oversight Process... the effectiveness of the reactor oversight process (ROP) baseline inspection program with members of... Nuclear Reactor Regulations, U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001; telephone: 301...

10 CFR 74.53 - Process monitoring.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 2 2013-01-01 2013-01-01 false Process monitoring. 74.53 Section 74.53 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear Material § 74.53 Process monitoring. (a) Licensees subject to § 74.51...

10 CFR 74.53 - Process monitoring.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 2 2011-01-01 2011-01-01 false Process monitoring. 74.53 Section 74.53 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear Material § 74.53 Process monitoring. (a) Licensees subject to § 74.51...

10 CFR 74.53 - Process monitoring.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 2 2012-01-01 2012-01-01 false Process monitoring. 74.53 Section 74.53 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear Material § 74.53 Process monitoring. (a) Licensees subject to § 74.51...

10 CFR 74.53 - Process monitoring.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 2 2014-01-01 2014-01-01 false Process monitoring. 74.53 Section 74.53 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Formula Quantities of Strategic Special Nuclear Material § 74.53 Process monitoring. (a) Licensees subject to § 74.51...

U.S.-Russian cooperation in nuclear disarmament and nonproliferation

NASA Astrophysics Data System (ADS)

Podvig, Pavel

2010-02-01

The United States and Russia, the two largest nuclear powers, have a special obligation to provide leadership in nuclear disarmament and in strengthening the nuclear non-proliferation regime. In the past year the two countries made an effort to restart the arms control process by concluding a new treaty that would bring their legal disarmament obligations in line with the realities of their post-cold war relationships. The process of negotiating deeper nuclear reductions in the new environment turned out to be rather difficult, since the approaches that the countries used in the past are not well suited to dealing with issues like conversion of strategic nuclear delivery systems to conventional missions, tactical nuclear weapons, or dismantlement of nuclear warheads. This presentation considers the recent progress in U.S.-Russian arms control process and outlines the key issues at the negotiations. It also considers prospects for further progress in bilateral nuclear disarmament and issues that will be encountered at later stages of the process. The author argues that success of the arms reductions will depend on whether the United States and Russia will be able to build an institutional framework for cooperation on a range of issues - from traditional arms control to securing nuclear materials and from missile defense to strengthening the international nuclear safeguards. )

FRENDY: A new nuclear data processing system being developed at JAEA

NASA Astrophysics Data System (ADS)

Tada, Kenichi; Nagaya, Yasunobu; Kunieda, Satoshi; Suyama, Kenya; Fukahori, Tokio

2017-09-01

JAEA has provided an evaluated nuclear data library JENDL and nuclear application codes such as MARBLE, SRAC, MVP and PHITS. These domestic codes have been widely used in many universities and industrial companies in Japan. However, we sometimes find problems in imported processing systems and need to revise them when the new JENDL is released. To overcome such problems and immediately process the nuclear data when it is released, JAEA started developing a new nuclear data processing system, FRENDY in 2013. This paper describes the outline of the development of FRENDY and both its capabilities and performances by the analyses of criticality experiments. The verification results indicate that FRENDY properly generates ACE files.

Socket welds in nuclear facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Anderson, P.A.; Torres, L.L.

1995-12-31

Socket welds are easier and faster to make than are butt welds. However, they are often not used in nuclear facilities because the crevices between the pipes and the socket sleeves may be subject to crevice corrosion. If socket welds can be qualified for wider use in facilities that process nuclear materials, the radiation exposures to welders can be significantly reduced. The current tests at the Idaho Chemical Processing Plant (ICPP) are designed to determine if socket welds can be qualified for use in the waste processing system at a nuclear fuel processing plant.

Environmental considerations

NASA Technical Reports Server (NTRS)

1975-01-01

A comparison was made between the environmental impact of the present nuclear-heated process and the currently commercial hydrogen-producing process utilizing coal for heating, i.e., the Lurgi coal gasification process. This comparison is based on the assumption that both plants produce the same quantity of H2, i.e., 269 cu m/sec of approximately the same purity, that all pollution abatement equipment is of the same design and efficiency for both the Lurgi process and the nuclear process, and that the energy required for the fresh nuclear fuel and the fuel recycle is generated in a power plant which is also provided with pollution abatement equipment. The pollution caused by the auxiliary units is also taken into account. As regards process water usage, the data show that the water required for the nuclear route, including the nuclear fuel production, is approximately 78% of that required for the Lurgi route.

Nuclear Weapons: NNSA Needs to Establish a Cost and Schedule Baseline for Manufacturing a Critical Nuclear Weapon Component

DTIC Science & Technology

2008-05-01

building up to and beyond the 2013 time frame. However, in October 2007, the Defense Nuclear Facilities Safety Board, which monitors safety...manufacturing. They said that NNSA is still working through this process with the Defense Nuclear Facilities Safety Board. Processing of waste

10 CFR 140.91 - Appendix A-Form of nuclear energy liability policy for facilities.

Code of Federal Regulations, 2010 CFR

2010-01-01

... designed or used for (a) separating the isotopes of uranium or plutonium, (b) processing or utilizing spent... processing, fabricating or alloying of special nuclear material if at any time the total amount of such... operations conducted thereat; Nuclear reactor means any apparatus designed or used to sustain nuclear fission...

10 CFR 140.91 - Appendix A-Form of nuclear energy liability policy for facilities.

Code of Federal Regulations, 2013 CFR

2013-01-01

... designed or used for (a) separating the isotopes of uranium or plutonium, (b) processing or utilizing spent... processing, fabricating or alloying of special nuclear material if at any time the total amount of such... operations conducted thereat; Nuclear reactor means any apparatus designed or used to sustain nuclear fission...

10 CFR 140.91 - Appendix A-Form of nuclear energy liability policy for facilities.

Code of Federal Regulations, 2014 CFR

2014-01-01

... designed or used for (a) separating the isotopes of uranium or plutonium, (b) processing or utilizing spent... processing, fabricating or alloying of special nuclear material if at any time the total amount of such... operations conducted thereat; Nuclear reactor means any apparatus designed or used to sustain nuclear fission...

10 CFR 140.91 - Appendix A-Form of nuclear energy liability policy for facilities.

Code of Federal Regulations, 2012 CFR

2012-01-01

... designed or used for (a) separating the isotopes of uranium or plutonium, (b) processing or utilizing spent... processing, fabricating or alloying of special nuclear material if at any time the total amount of such... operations conducted thereat; Nuclear reactor means any apparatus designed or used to sustain nuclear fission...

10 CFR 140.91 - Appendix A-Form of nuclear energy liability policy for facilities.

Code of Federal Regulations, 2011 CFR

2011-01-01

... designed or used for (a) separating the isotopes of uranium or plutonium, (b) processing or utilizing spent... processing, fabricating or alloying of special nuclear material if at any time the total amount of such... operations conducted thereat; Nuclear reactor means any apparatus designed or used to sustain nuclear fission...

76 FR 34007 - Draft Regulatory Basis for a Potential Rulemaking on Spent Nuclear Fuel Reprocessing Facilities

Federal Register 2010, 2011, 2012, 2013, 2014

2011-06-10

... processes are more akin to fuel cycle processes. This framework was established in the 1970's to license the... nuclear power globally and close the nuclear fuel cycle through reprocessing spent fuel and deploying fast... Accounting;'' and a Nuclear Energy Institute white [[Page 34009

Dynamics and Function of Nuclear Bodies during Embryogenesis.

PubMed

Arias Escayola, Dahyana; Neugebauer, Karla M

2018-05-01

Nuclear bodies are RNA-rich membraneless organelles in the cell nucleus that concentrate specific sets of nuclear proteins and RNA-protein complexes. Nuclear bodies such as the nucleolus, Cajal body (CB), and the histone locus body (HLB) concentrate factors required for nuclear steps of RNA processing. Formation of these nuclear bodies occurs on genomic loci and is frequently associated with active sites of transcription. Whether nuclear body formation is dependent on a particular gene element, an active process such as transcription, or the nascent RNA present at gene loci is a topic of debate. Recently, this question has been addressed through studies in model organisms and their embryos. The switch from maternally provided RNA and protein to zygotic gene products in early embryos has been well characterized in a variety of organisms. This process, termed maternal-to-zygotic transition, provides an excellent model for studying formation of nuclear bodies before, during, and after the transcriptional activation of the zygotic genome. Here, we review findings in embryos that reveal key principles in the study of the formation and function of nucleoli, CBs, and HLBs. We propose that while particular gene elements may contribute to formation of these nuclear bodies, active transcription promotes maturation of nuclear bodies and efficient RNA processing within them.

Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power

DTIC Science & Technology

2007-11-01

critical aspect of the nuclear fuel cycle for the United States, where longstanding nonproliferation policy discouraged commercial nuclear fuel...perhaps the most critical question in this decade for strengthening the nuclear nonproliferation regime: how can access to sensitive fuel cycle...process can take advantage of the slight difference in atomic mass between 235U and 238U. The typical enrichment process requires about 10 lbs of uranium

JOWOG 22/2 - Actinide Chemical Technology (July 9-13, 2012)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jackson, Jay M.; Lopez, Jacquelyn C.; Wayne, David M.

2012-07-05

The Plutonium Science and Manufacturing Directorate provides world-class, safe, secure, and reliable special nuclear material research, process development, technology demonstration, and manufacturing capabilities that support the nation's defense, energy, and environmental needs. We safely and efficiently process plutonium, uranium, and other actinide materials to meet national program requirements, while expanding the scientific and engineering basis of nuclear weapons-based manufacturing, and while producing the next generation of nuclear engineers and scientists. Actinide Process Chemistry (NCO-2) safely and efficiently processes plutonium and other actinide compounds to meet the nation's nuclear defense program needs. All of our processing activities are done in amore » world class and highly regulated nuclear facility. NCO-2's plutonium processing activities consist of direct oxide reduction, metal chlorination, americium extraction, and electrorefining. In addition, NCO-2 uses hydrochloric and nitric acid dissolutions for both plutonium processing and reduction of hazardous components in the waste streams. Finally, NCO-2 is a key team member in the processing of plutonium oxide from disassembled pits and the subsequent stabilization of plutonium oxide for safe and stable long-term storage.« less

Direct nuclear-powered lasers

NASA Technical Reports Server (NTRS)

Jalufka, N. W.

1983-01-01

The development of direct nuclear pumped lasers is reviewed. Theoretical and experimental investigations of various methods of converting the energy of nuclear fission fragments to laser power are summarized. The development of direct nuclear pumped lasers was achieved. The basic processes involved in the production of a plasma by nuclear radiation were studied. Significant progress was accomplished in this area and a large amount of basic data on plasma formation and atomic and molecular processes leading to population inversions is available.

Chemical processing in geothermal nuclear chimney

DOEpatents

Krikorian, O.H.

1973-10-01

A closed rubble filled nuclear chimney is provided in a subterranean geothermal formation by detonation of a nuclear explosive device therein, with reagent input and product output conduits connecting the chimney cavity with appropriate surface facilities. Such facilities will usually comprise reagent preparation, product recovery and recycle facilities. Proccsses are then conducted in the nuclear chimney which processes are facilitated by temperature, pressure, catalytic and other conditions existent or which are otherwise provided in the nuclear chimney. (auth)

Electron-Nuclear Quantum Information Processing

DTIC Science & Technology

2008-11-13

quantum information processing that exploits the anisotropic hyperfine coupling. This scheme enables universal control over a 1-electron, N-nuclear spin...exploits the anisotropic hyperfine coupling. This scheme enables universal control over a 1-electron, N-nuclear spin system, addressing only a...sample of irradiated malonic acid. (a) Papers published in peer-reviewed journals (N/A for none) Universal control of nuclear spins via anisotropic

Production of Synthetic Nuclear Melt Glass

PubMed Central

Molgaard, Joshua J.; Auxier, John D.; Giminaro, Andrew V.; Oldham, Colton J.; Gill, Jonathan; Hall, Howard L.

2016-01-01

Realistic surrogate nuclear debris is needed within the nuclear forensics community to test and validate post-detonation analysis techniques. Here we outline a novel process for producing bulk surface debris using a high temperature furnace. The material developed in this study is physically and chemically similar to trinitite (the melt glass produced by the first nuclear test). This synthetic nuclear melt glass is assumed to be similar to the vitrified material produced near the epicenter (ground zero) of any surface nuclear detonation in a desert environment. The process outlined here can be applied to produce other types of nuclear melt glass including that likely to be formed in an urban environment. This can be accomplished by simply modifying the precursor matrix to which this production process is applied. The melt glass produced in this study has been analyzed and compared to trinitite, revealing a comparable crystalline morphology, physical structure, void fraction, and chemical composition. PMID:26779720

Systematic and statistical uncertainties in simulated r-process abundances due to uncertain nuclear masses

DOE PAGES

Surman, Rebecca; Mumpower, Matthew; McLaughlin, Gail

2017-02-27

Unknown nuclear masses are a major source of nuclear physics uncertainty for r-process nucleosynthesis calculations. Here we examine the systematic and statistical uncertainties that arise in r-process abundance predictions due to uncertainties in the masses of nuclear species on the neutron-rich side of stability. There is a long history of examining systematic uncertainties by the application of a variety of different mass models to r-process calculations. Here we expand upon such efforts by examining six DFT mass models, where we capture the full impact of each mass model by updating the other nuclear properties — including neutron capture rates, β-decaymore » lifetimes, and β-delayed neutron emission probabilities — that depend on the masses. Unlike systematic effects, statistical uncertainties in the r-process pattern have just begun to be explored. Here we apply a global Monte Carlo approach, starting from the latest FRDM masses and considering random mass variations within the FRDM rms error. Here, we find in each approach that uncertain nuclear masses produce dramatic uncertainties in calculated r-process yields, which can be reduced in upcoming experimental campaigns.« less

Systematic and statistical uncertainties in simulated r-process abundances due to uncertain nuclear masses

DOE Office of Scientific and Technical Information (OSTI.GOV)

Surman, Rebecca; Mumpower, Matthew; McLaughlin, Gail

Unknown nuclear masses are a major source of nuclear physics uncertainty for r-process nucleosynthesis calculations. Here we examine the systematic and statistical uncertainties that arise in r-process abundance predictions due to uncertainties in the masses of nuclear species on the neutron-rich side of stability. There is a long history of examining systematic uncertainties by the application of a variety of different mass models to r-process calculations. Here we expand upon such efforts by examining six DFT mass models, where we capture the full impact of each mass model by updating the other nuclear properties — including neutron capture rates, β-decaymore » lifetimes, and β-delayed neutron emission probabilities — that depend on the masses. Unlike systematic effects, statistical uncertainties in the r-process pattern have just begun to be explored. Here we apply a global Monte Carlo approach, starting from the latest FRDM masses and considering random mass variations within the FRDM rms error. Here, we find in each approach that uncertain nuclear masses produce dramatic uncertainties in calculated r-process yields, which can be reduced in upcoming experimental campaigns.« less

Theoretical model of dynamic spin polarization of nuclei coupled to paramagnetic point defects in diamond and silicon carbide

NASA Astrophysics Data System (ADS)

Ivády, Viktor; Szász, Krisztián; Falk, Abram L.; Klimov, Paul V.; Christle, David J.; Janzén, Erik; Abrikosov, Igor A.; Awschalom, David D.; Gali, Adam

2015-09-01

Dynamic nuclear spin polarization (DNP) mediated by paramagnetic point defects in semiconductors is a key resource for both initializing nuclear quantum memories and producing nuclear hyperpolarization. DNP is therefore an important process in the field of quantum-information processing, sensitivity-enhanced nuclear magnetic resonance, and nuclear-spin-based spintronics. DNP based on optical pumping of point defects has been demonstrated by using the electron spin of nitrogen-vacancy (NV) center in diamond, and more recently, by using divacancy and related defect spins in hexagonal silicon carbide (SiC). Here, we describe a general model for these optical DNP processes that allows the effects of many microscopic processes to be integrated. Applying this theory, we gain a deeper insight into dynamic nuclear spin polarization and the physics of diamond and SiC defects. Our results are in good agreement with experimental observations and provide a detailed and unified understanding. In particular, our findings show that the defect electron spin coherence times and excited state lifetimes are crucial factors in the entire DNP process.

Nuclear parton distributions and the Drell-Yan process

NASA Astrophysics Data System (ADS)

Kulagin, S. A.; Petti, R.

2014-10-01

We study the nuclear parton distribution functions on the basis of our recently developed semimicroscopic model, which takes into account a number of nuclear effects including nuclear shadowing, Fermi motion and nuclear binding, nuclear meson-exchange currents, and off-shell corrections to bound nucleon distributions. We discuss in detail the dependencies of nuclear effects on the type of parton distribution (nuclear sea vs valence), as well as on the parton flavor (isospin). We apply the resulting nuclear parton distributions to calculate ratios of cross sections for proton-induced Drell-Yan production off different nuclear targets. We obtain a good agreement on the magnitude, target and projectile x, and the dimuon mass dependence of proton-nucleus Drell-Yan process data from the E772 and E866 experiments at Fermilab. We also provide nuclear corrections for the Drell-Yan data from the E605 experiment.

Reverse engineering nuclear properties from rare earth abundances in the r process

NASA Astrophysics Data System (ADS)

Mumpower, M. R.; McLaughlin, G. C.; Surman, R.; Steiner, A. W.

2017-03-01

The bulk of the rare earth elements are believed to be synthesized in the rapid neutron capture process or r process of nucleosynthesis. The solar r-process residuals show a small peak in the rare earths around A∼ 160, which is proposed to be formed dynamically during the end phase of the r process by a pileup of material. This abundance feature is of particular importance as it is sensitive to both the nuclear physics inputs and the astrophysical conditions of the main r process. We explore the formation of the rare earth peak from the perspective of an inverse problem, using Monte Carlo studies of nuclear masses to investigate the unknown nuclear properties required to best match rare earth abundance sector of the solar isotopic residuals. When nuclear masses are changed, we recalculate the relevant β-decay properties and neutron capture rates in the rare earth region. The feedback provided by this observational constraint allows for the reverse engineering of nuclear properties far from stability where no experimental information exists. We investigate a range of astrophysical conditions with this method and show how these lead to different predictions in the nuclear properties influential to the formation of the rare earth peak. We conclude that targeted experimental campaigns in this region will help to resolve the type of conditions responsible for the production of the rare earth nuclei, and will provide new insights into the longstanding problem of the astrophysical site(s) of the r process.

Recent Advances in Resonance Region Nuclear Data Measurements and Analyses for Supporting Nuclear Energy Applications

NASA Astrophysics Data System (ADS)

Dunn, Michael

2008-10-01

For over 30 years, the Oak Ridge National Laboratory (ORNL) has performed research and development to provide more accurate nuclear cross-section data in the resonance region. The ORNL Nuclear Data (ND) Program consists of four complementary areas of research: (1) cross-section measurements at the Oak Ridge Electron Linear Accelerator; (2) resonance analysis methods development with the SAMMY R-matrix analysis software; (3) cross-section evaluation development; and (4) cross-section processing methods development with the AMPX software system. The ND Program is tightly coupled with nuclear fuel cycle analyses and radiation transport methods development efforts at ORNL. Thus, nuclear data work is performed in concert with nuclear science and technology needs and requirements. Recent advances in each component of the ORNL ND Program have led to improvements in resonance region measurements, R-matrix analyses, cross-section evaluations, and processing capabilities that directly support radiation transport research and development. Of particular importance are the improvements in cross-section covariance data evaluation and processing capabilities. The benefit of these advances to nuclear science and technology research and development will be discussed during the symposium on Nuclear Physics Research Connections to Nuclear Energy.

77 FR 53236 - Proposed International Isotopes Fluorine Extraction Process and Depleted Uranium Deconversion...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-31

... NUCLEAR REGULATORY COMMISSION [NRC-2010-0143] Proposed International Isotopes Fluorine Extraction Process and Depleted Uranium Deconversion Plant in Lea County, New Mexico AGENCY: Nuclear Regulatory... U.S. Nuclear Regulatory Commission (NRC or the Commission) has published the Final Environmental...

The use of a very high temperature nuclear reactor in the manufacture of synthetic fuels

NASA Technical Reports Server (NTRS)

Farbman, G. H.; Brecher, L. E.

1976-01-01

The three parts of a program directed toward creating a cost-effective nuclear hydrogen production system are described. The discussion covers the development of a very high temperature nuclear reactor (VHTR) as a nuclear heat and power source capable of producing the high temperature needed for hydrogen production and other processes; the development of a hydrogen generation process based on water decomposition, which can utilize the outputs of the VHTR and be integrated with many different ultimate hydrogen consuming processes; and the evaluation of the process applications of the nuclear hydrogen systems to assess the merits and potential payoffs. It is shown that the use of VHTR for the manufacture of synthetic fuels appears to have a very high probability of making a positive contribution to meeting the nation's energy needs in the future.

Current state of nuclear fuel cycles in nuclear engineering and trends in their development according to the environmental safety requirements

NASA Astrophysics Data System (ADS)

Vislov, I. S.; Pischulin, V. P.; Kladiev, S. N.; Slobodyan, S. M.

2016-08-01

The state and trends in the development of nuclear fuel cycles in nuclear engineering, taking into account the ecological aspects of using nuclear power plants, are considered. An analysis of advantages and disadvantages of nuclear engineering, compared with thermal engineering based on organic fuel types, was carried out. Spent nuclear fuel (SNF) reprocessing is an important task in the nuclear industry, since fuel unloaded from modern reactors of any type contains a large amount of radioactive elements that are harmful to the environment. On the other hand, the newly generated isotopes of uranium and plutonium should be reused to fabricate new nuclear fuel. The spent nuclear fuel also includes other types of fission products. Conditions for SNF handling are determined by ecological and economic factors. When choosing a certain handling method, one should assess these factors at all stages of its implementation. There are two main methods of SNF handling: open nuclear fuel cycle, with spent nuclear fuel assemblies (NFAs) that are held in storage facilities with their consequent disposal, and closed nuclear fuel cycle, with separation of uranium and plutonium, their purification from fission products, and use for producing new fuel batches. The development of effective closed fuel cycles using mixed uranium-plutonium fuel can provide a successful development of the nuclear industry only under the conditions of implementation of novel effective technological treatment processes that meet strict requirements of environmental safety and reliability of process equipment being applied. The diversity of technological processes is determined by different types of NFA devices and construction materials being used, as well as by the composition that depends on nuclear fuel components and operational conditions for assemblies in the nuclear power reactor. This work provides an overview of technological processes of SNF treatment and methods of handling of nuclear fuel assemblies. Based on analysis of modern engineering solutions on SNF regeneration, it has been concluded that new reprocessing technologies should meet the ecological safety requirements, provide a more extensive use of the resource base of nuclear engineering, allow the production of valuable and trace elements on an industrial scale, and decrease radioactive waste release.

Organellar proteomics reveals hundreds of novel nuclear proteins in the malaria parasite Plasmodium falciparum

PubMed Central

2012-01-01

Background The post-genomic era of malaria research provided unprecedented insights into the biology of Plasmodium parasites. Due to the large evolutionary distance to model eukaryotes, however, we lack a profound understanding of many processes in Plasmodium biology. One example is the cell nucleus, which controls the parasite genome in a development- and cell cycle-specific manner through mostly unknown mechanisms. To study this important organelle in detail, we conducted an integrative analysis of the P. falciparum nuclear proteome. Results We combined high accuracy mass spectrometry and bioinformatic approaches to present for the first time an experimentally determined core nuclear proteome for P. falciparum. Besides a large number of factors implicated in known nuclear processes, one-third of all detected proteins carry no functional annotation, including many phylum- or genus-specific factors. Importantly, extensive experimental validation using 30 transgenic cell lines confirmed the high specificity of this inventory, and revealed distinct nuclear localization patterns of hitherto uncharacterized proteins. Further, our detailed analysis identified novel protein domains potentially implicated in gene transcription pathways, and sheds important new light on nuclear compartments and processes including regulatory complexes, the nucleolus, nuclear pores, and nuclear import pathways. Conclusion Our study provides comprehensive new insight into the biology of the Plasmodium nucleus and will serve as an important platform for dissecting general and parasite-specific nuclear processes in malaria parasites. Moreover, as the first nuclear proteome characterized in any protist organism, it will provide an important resource for studying evolutionary aspects of nuclear biology. PMID:23181666

Insight into nuclear body formation of phytochromes through stochastic modelling and experiment.

PubMed

Grima, Ramon; Sonntag, Sebastian; Venezia, Filippo; Kircher, Stefan; Smith, Robert W; Fleck, Christian

2018-05-01

Spatial relocalization of proteins is crucial for the correct functioning of living cells. An interesting example of spatial ordering is the light-induced clustering of plant photoreceptor proteins. Upon irradiation by white or red light, the red light-active phytochrome, phytochrome B, enters the nucleus and accumulates in large nuclear bodies. The underlying physical process of nuclear body formation remains unclear, but phytochrome B is thought to coagulate via a simple protein-protein binding process. We measure, for the first time, the distribution of the number of phytochrome B-containing nuclear bodies as well as their volume distribution. We show that the experimental data cannot be explained by a stochastic model of nuclear body formation via simple protein-protein binding processes using physically meaningful parameter values. Rather modelling suggests that the data is consistent with a two step process: a fast nucleation step leading to macroparticles followed by a subsequent slow step in which the macroparticles bind to form the nuclear body. An alternative explanation for the observed nuclear body distribution is that the phytochromes bind to a so far unknown molecular structure. We believe it is likely this result holds more generally for other nuclear body-forming plant photoreceptors and proteins. Creative Commons Attribution license.

Nuclear Technology Series. Course 5: Introduction to Nuclear Systems.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 24: Nuclear Systems and Safety.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Exodus: Herpesviruses Lead the Way

PubMed Central

Bigalke, Janna M.; Heldwein, Ekaterina E.

2016-01-01

Most DNA viruses replicate in the nucleus and exit it either by passing through the nuclear pores or by rupturing the nuclear envelope. Unusually, herpesviruses have evolved a complex mechanism of nuclear escape whereby nascent capsids bud at the inner nuclear membrane to form perinuclear virions that subsequently fuse with the outer nuclear membrane, releasing capsids into the cytosol. Although this general scheme is accepted in the field, the players and their roles are still debated. Recent studies illuminated critical mechanistic features of this enigmatic process and uncovered surprising parallels with a novel cellular nuclear export process. This review summarizes our current understanding of nuclear egress in herpesviruses, examines the experimental evidence and models, and outlines outstanding questions with the goal of stimulating new research in this area. PMID:27482898

Reverse engineering nuclear properties from rare earth abundances in the r process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mumpower, Matthew Ryan; McLaughlin, G. C.; Surman, R.

The bulk of the rare earth elements are believed to be synthesized in the rapid neutron capture process or r process of nucleosynthesis. The solar r-process residuals show a small peak in the rare earths aroundmore » $$A\\sim 160$$, which is proposed to be formed dynamically during the end phase of the r process by a pileup of material. This abundance feature is of particular importance as it is sensitive to both the nuclear physics inputs and the astrophysical conditions of the main r process. Here, we explore the formation of the rare earth peak from the perspective of an inverse problem, using Monte Carlo studies of nuclear masses to investigate the unknown nuclear properties required to best match rare earth abundance sector of the solar isotopic residuals. When nuclear masses are changed, we recalculate the relevant β-decay properties and neutron capture rates in the rare earth region. The feedback provided by this observational constraint allows for the reverse engineering of nuclear properties far from stability where no experimental information exists. We investigate a range of astrophysical conditions with this method and show how these lead to different predictions in the nuclear properties influential to the formation of the rare earth peak. Finally, we conclude that targeted experimental campaigns in this region will help to resolve the type of conditions responsible for the production of the rare earth nuclei, and will provide new insights into the longstanding problem of the astrophysical site(s) of the r process.« less

Reverse engineering nuclear properties from rare earth abundances in the r process

DOE PAGES

Mumpower, Matthew Ryan; McLaughlin, G. C.; Surman, R.; ...

2017-02-01

The bulk of the rare earth elements are believed to be synthesized in the rapid neutron capture process or r process of nucleosynthesis. The solar r-process residuals show a small peak in the rare earths aroundmore » $$A\\sim 160$$, which is proposed to be formed dynamically during the end phase of the r process by a pileup of material. This abundance feature is of particular importance as it is sensitive to both the nuclear physics inputs and the astrophysical conditions of the main r process. Here, we explore the formation of the rare earth peak from the perspective of an inverse problem, using Monte Carlo studies of nuclear masses to investigate the unknown nuclear properties required to best match rare earth abundance sector of the solar isotopic residuals. When nuclear masses are changed, we recalculate the relevant β-decay properties and neutron capture rates in the rare earth region. The feedback provided by this observational constraint allows for the reverse engineering of nuclear properties far from stability where no experimental information exists. We investigate a range of astrophysical conditions with this method and show how these lead to different predictions in the nuclear properties influential to the formation of the rare earth peak. Finally, we conclude that targeted experimental campaigns in this region will help to resolve the type of conditions responsible for the production of the rare earth nuclei, and will provide new insights into the longstanding problem of the astrophysical site(s) of the r process.« less

Study of components and statistical reaction mechanism in simulation of nuclear process for optimized production of {sup 64}Cu and {sup 67}Ga medical radioisotopes using TALYS, EMPIRE and LISE++ nuclear reaction and evaporation codes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nasrabadi, M. N., E-mail: mnnasrabadi@ast.ui.ac.ir; Sepiani, M.

2015-03-30

Production of medical radioisotopes is one of the most important tasks in the field of nuclear technology. These radioactive isotopes are mainly produced through variety nuclear process. In this research, excitation functions and nuclear reaction mechanisms are studied for simulation of production of these radioisotopes in the TALYS, EMPIRE and LISE++ reaction codes, then parameters and different models of nuclear level density as one of the most important components in statistical reaction models are adjusted for optimum production of desired radioactive yields.

Study of components and statistical reaction mechanism in simulation of nuclear process for optimized production of 64Cu and 67Ga medical radioisotopes using TALYS, EMPIRE and LISE++ nuclear reaction and evaporation codes

NASA Astrophysics Data System (ADS)

Nasrabadi, M. N.; Sepiani, M.

2015-03-01

Production of medical radioisotopes is one of the most important tasks in the field of nuclear technology. These radioactive isotopes are mainly produced through variety nuclear process. In this research, excitation functions and nuclear reaction mechanisms are studied for simulation of production of these radioisotopes in the TALYS, EMPIRE & LISE++ reaction codes, then parameters and different models of nuclear level density as one of the most important components in statistical reaction models are adjusted for optimum production of desired radioactive yields.

The Nuclear Power and Nuclear Weapons Connection.

ERIC Educational Resources Information Center

Leventhal, Paul

1990-01-01

Explains problems enforcing the Nuclear Non-Proliferation Treaty (NPT) of 1968. Provides factual charts and details concerning the production of nuclear energy and arms, the processing and disposal of waste products, and outlines the nuclear fuel cycle. Discusses safeguards, the risk of nuclear terrorism, and ways to deal with these problems. (NL)

Nuclear data for r-process models from ion trap measurements

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clark, Jason, E-mail: jclark@anl.gov

2016-06-21

To truly understand how elements are created in the universe via the astrophysical r process, accurate nuclear data are required. Historically, the isotopes involved in the r process have been difficult to access for study, but the development of new facilities and measurement techniques have put many of the r-process isotopes within reach. This paper will discuss the new CARIBU facility at Argonne National Laboratory and two pieces of experimental equipment, the Beta-decay Paul Trap and the Canadian Penning Trap, that will dramatically increase the nuclear data available for models of the astrophysical r process.

H CANYON PROCESSING IN CORRELATION WITH FH ANALYTICAL LABS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Weinheimer, E.

2012-08-06

Management of radioactive chemical waste can be a complicated business. H Canyon and F/H Analytical Labs are two facilities present at the Savannah River Site in Aiken, SC that are at the forefront. In fact H Canyon is the only large-scale radiochemical processing facility in the United States and this processing is only enhanced by the aid given from F/H Analytical Labs. As H Canyon processes incoming materials, F/H Labs provide support through a variety of chemical analyses. Necessary checks of the chemical makeup, processing, and accountability of the samples taken from H Canyon process tanks are performed at themore » labs along with further checks on waste leaving the canyon after processing. Used nuclear material taken in by the canyon is actually not waste. Only a small portion of the radioactive material itself is actually consumed in nuclear reactors. As a result various radioactive elements such as Uranium, Plutonium and Neptunium are commonly found in waste and may be useful to recover. Specific processing is needed to allow for separation of these products from the waste. This is H Canyon's specialty. Furthermore, H Canyon has the capacity to initiate the process for weapons-grade nuclear material to be converted into nuclear fuel. This is one of the main campaigns being set up for the fall of 2012. Once usable material is separated and purified of impurities such as fission products, it can be converted to an oxide and ultimately turned into commercial fuel. The processing of weapons-grade material for commercial fuel is important in the necessary disposition of plutonium. Another processing campaign to start in the fall in H Canyon involves the reprocessing of used nuclear fuel for disposal in improved containment units. The importance of this campaign involves the proper disposal of nuclear waste in order to ensure the safety and well-being of future generations and the environment. As processing proceeds in the fall, H Canyon will have a substantial number of samples being sent to F/H Labs. All analyses of these samples are imperative to safe and efficient processing. The important campaigns to occur would be impossible without feedback from analyses such as chemical makeup of solutions, concentrations of dissolution acids and nuclear material, as well as nuclear isotopic data. The necessity of analysis for radiochemical processing is evident. Processing devoid of F/H Lab's feedback would go against the ideals of a safety-conscious and highly accomplished processing facility such as H Canyon.« less

75 FR 30078 - Entergy Nuclear Operations, Inc.; Entergy Nuclear Vermont Yankee, LLC; Vermont Yankee Nuclear...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-28

... remediation work and relevant reports on leaking tritium at the plant have been completed. Specifically, the... has been completed to the Commission's satisfaction: (1) The tritiated groundwater remediation process; (2) the soil remediation process scheduled to take place during the refueling outage, to remove soil...

Nuclear Technology Series. Course 27: Metrology.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

78 FR 64028 - Decommissioning of Nuclear Power Reactors

Federal Register 2010, 2011, 2012, 2013, 2014

2013-10-25

... NUCLEAR REGULATORY COMMISSION [NRC-2012-0035] Decommissioning of Nuclear Power Reactors AGENCY... Commission (NRC) is issuing Revision 1 of regulatory guide (RG) 1.184 ``Decommissioning of Nuclear Power... the NRC's regulations relating to the decommissioning process for nuclear power reactors. The revision...

Nuclear Migration During Retinal Development

PubMed Central

Baye, Lisa M.; Link, Brian A.

2009-01-01

In this review we focus on the mechanisms, regulation, and cellular consequences of nuclear migration in the developing retina. In the nervous system, nuclear migration is prominent during both proliferative and post-mitotic phases of development. Interkinetic nuclear migration is the process where the nucleus oscillates from the apical to basal surfaces in proliferative neuroepithelia. Proliferative nuclear movement occurs in step with the cell cycle, with M-phase being confined to the apical surface and G1-, S-, and G2-phases occurring at more basal locations. Later, following cell cycle exit, some neuron precursors migrate by nuclear translocation. In this mode of cellular migration, nuclear movement is the driving force for motility. Following discussion of the key components and important regulators for each of these processes, we present an emerging model where interkinetic nuclear migration functions to distinguish cell fates among retinal neuroepithelia. PMID:17560964

77 FR 50724 - Developing Software Life Cycle Processes for Digital Computer Software Used in Safety Systems of...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-08-22

... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Developing Software Life Cycle Processes for Digital... Software Life Cycle Processes for Digital Computer Software used in Safety Systems of Nuclear Power Plants... clarifications, the enhanced consensus practices for developing software life-cycle processes for digital...

Application of Ion Exchange Technique to Decontamination of Polluted Water Generated by Fukushima Nuclear Disaster

NASA Astrophysics Data System (ADS)

Takeshita, Kenji; Ogata, Takeshi

By the Fukushima nuclear disaster, large amounts of water and sea water polluted mainly with radioactive Cs were generated and the environment around the nuclear site was contaminated by the fallout from the nuclear site. The coagulation settling process using ferric ferrocyanide and an inorganic coagulant and the adsorption process using ferric ferrocyanide granulated by silica binder were applied to the treatment of polluted water. In the coagulation settling process, Cs was removed completely from polluted water and sea water (DF∼104). In the adsorption process, the recovery of trace Cs (10 ppb) in sea water, which was not suitable for the use of zeolite, was attained successfully. Finally, the recovery of Cs from sewage sludge was tested by a combined process with the hydrothermal process using subcritical water and the coagulation settling process using ferric ferrocyanide. 96% of radioactive Cs was recovered successfully from sewage sludge with the radioactivity of 10,000 Bq/kg.

Development of Curricula for Nuclear Radiation Protection, Nuclear Instrumentation, and Nuclear Materials Processing Technologies. Final Report.

ERIC Educational Resources Information Center

Hull, Daniel M.

A study was conducted to assist two-year postsecondary educational institutions in providing technical specialty courses for preparing nuclear technicians. As a result of project activities, curricula have been developed for five categories of nuclear technicians and operators: (1) radiation protection technician, (2) nuclear instrumentation and…

Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power

DTIC Science & Technology

2008-09-03

Spent nuclear fuel disposal has remained the most critical aspect of the nuclear fuel cycle for the United States, where longstanding nonproliferation...inalienable right and by and large, neither have U.S. government officials. However, the case of Iran raises perhaps the most critical question in...the enrichment process can take advantage of the slight difference in atomic mass between 235U and 238U. The typical enrichment process requires

Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power

DTIC Science & Technology

2010-03-05

However, the case of Iran raises perhaps the most critical question in this decade for strengthening the nuclear nonproliferation regime: How can...enrichment process can take advantage of the slight difference in atomic mass between 235U and 238U. The typical enrichment process requires about 10 lbs of...neutrons but can induce fission in all actinides , including all plutonium isotopes. Therefore, nuclear fuel for a fast reactor must have a higher

Nuclear Technology Series. Course 35: Systems and Components.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course l: Radiation Physics.

ERIC Educational Resources Information Center

Technical Education Research Center, Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 10: Power Plant Systems.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 7: Reactor Operations.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 22: Advanced Radionuclide Analysis.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 19: Radiation Shielding.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 8: Reactor Safety.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutians in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 9: Reactor Auxiliary Systems.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 13: Power Plant Chemistry.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 17: Radiation Protection II.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 18: Radiological Emergencies.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 2: Radiation Protection I.

ERIC Educational Resources Information Center

Technical Education Research Center, Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 12: Reactor Physics.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 28: Welding Inspection.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 30: Mechanical Inspection.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 31: Quality-Assurance Practices.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 33: Control Systems I.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 29: Civil/Structural Inspection.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 34: Control Systems II.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Super-resolution microscopy reveals LINC complex recruitment at nuclear indentation sites.

PubMed

Versaevel, Marie; Braquenier, Jean-Baptiste; Riaz, Maryam; Grevesse, Thomas; Lantoine, Joséphine; Gabriele, Sylvain

2014-12-08

Increasing evidences show that the actin cytoskeleton is a key parameter of the nuclear remodeling process in response to the modifications of cellular morphology. However, detailed information on the interaction between the actin cytoskeleton and the nuclear lamina was still lacking. We addressed this question by constraining endothelial cells on rectangular fibronectin-coated micropatterns and then using Structured Illumination Microscopy (SIM) to observe the interactions between actin stress fibers, nuclear lamina and LINC complexes at a super-resolution scale. Our results show that tension in apical actin stress fibers leads to deep nuclear indentations that significantly deform the nuclear lamina. Interestingly, indented nuclear zones are characterized by a local enrichment of LINC complexes, which anchor apical actin fibers to the nuclear lamina. Moreover, our findings indicate that nuclear indentations induce the formation of segregated domains of condensed chromatin. However, nuclear indentations and condensed chromatin domains are not irreversible processes and both can relax in absence of tension in apical actin stress fibers.

The myth of the ``proliferation-resistant'' closed nuclear fuel cycle

NASA Astrophysics Data System (ADS)

Lyman, Edwin S.

2000-07-01

National nuclear energy programs that engage in reprocessing of spent nuclear fuel (SNF) and the development of "closed" nuclear fuel cycles based on the utilization of plutonium process and store large quantities of weapons-usable nuclear materials in forms vulnerable to diversion or theft by national or subnational groups. Proliferation resistance, an idea dating back at least as far as the International Fuel Cycle Evaluation (INFCE) of the late 1970s, is a loosely defined term referring to processes for chemical separation of SNF that do not extract weapons-usable materials in a purified form.

On-line condition monitoring applications in nuclear power plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hastiemian, H. M.; Feltus, M. A.

2006-07-01

Existing signals from process instruments in nuclear power plants can be sampled while the plant is operating and analyzed to verify the static and dynamic performance of process sensors, identify process-to-sensor problems, detect instrument anomalies such as venturi fouling, measure the vibration of the reactor vessel and its internals, or detect thermal hydraulic anomalies within the reactor coolant system. These applications are important in nuclear plants to satisfy a variety of objectives such as: 1) meeting the plant technical specification requirements; 2) complying with regulatory regulations; 3) guarding against equipment and process degradation; 4) providing a means for incipient failuremore » detection and predictive maintenance; or 5) identifying the root cause of anomalies in equipment and plant processes. The technologies that are used to achieve these objectives are collectively referred to as 'on-line condition monitoring.' This paper presents a review of key elements of these technologies, provides examples of their use in nuclear power plants, and illustrates how they can be integrated into an on-line condition monitoring system for nuclear power plants. (authors)« less

Electron microscopic characterization of nuclear egress in the sea urchin gastrula.

PubMed

LaMassa, Nicole; Arenas-Mena, Cesar; Phillips, Greg R

2018-05-01

Nuclear egress, also referred to as nuclear envelope (NE) budding, is a process of transport in which vesicles containing molecular complexes or viral particles leave the nucleus through budding from the inner nuclear membrane (INM) to enter the perinuclear space. Following this event, the perinuclear vesicles (PNVs) fuse with the outer nuclear membrane (ONM), where they release their contents into the cytoplasm. Nuclear egress is thought to participate in many functions such as viral replication, cellular differentiation, and synaptic development. The molecular basis for nuclear egress is now beginning to be elucidated. Here, we observe in the sea urchin gastrula, using serial section transmission electron microscopy, strikingly abundant PNVs containing as yet unidentified granules that resemble the ribonucleoprotein complexes (RNPs) previously observed in similar types of PNVs. Some PNVs were observed in the process of fusion with the ONM where they appeared to release their contents into the cytoplasm. These vesicles were abundantly observed in all three presumptive germ layers. These findings indicate that nuclear egress is likely to be an important mechanism for nucleocytoplasmic transfer during sea urchin development. The sea urchin may be a useful model to characterize further and gain a better understanding of the process of nuclear egress. © 2018 Wiley Periodicals, Inc.

Nuclear Technology Series. Course 16: Mechanical Component Characteristics and Specifications.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 11: Radiation Detection and Measurement.

ERIC Educational Resources Information Center

Technical Education Research Center, Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 4: Heat Transfer and Fluid Flow.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 20: Radiation Monitoring Techniques (Radiochemical).

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 32: Nondestructive Examination (NDE) Techniques II.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 15: Metallurgy and Metals Properties.

ERIC Educational Resources Information Center

Technical Education Research Center, Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 26: Nondestructive Examination (NDE) Techniques I.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 21: Radioactive Materials Disposal and Management.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 25: Radioactive Material Handling Techniques.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

New Features in the Computational Infrastructure for Nuclear Astrophysics

NASA Astrophysics Data System (ADS)

Smith, M. S.; Lingerfelt, E. J.; Scott, J. P.; Hix, W. R.; Nesaraja, C. D.; Koura, H.; Roberts, L. F.

2006-04-01

The Computational Infrastructure for Nuclear Astrophysics is a suite of computer codes online at nucastrodata.org that streamlines the incorporation of recent nuclear physics results into astrophysical simulations. The freely-available, cross- platform suite enables users to upload cross sections and s-factors, convert them into reaction rates, parameterize the rates, store the rates in customizable libraries, setup and run custom post-processing element synthesis calculations, and visualize the results. New features include the ability for users to comment on rates or libraries using an email-type interface, a nuclear mass model evaluator, enhanced techniques for rate parameterization, better treatment of rate inverses, and creation and exporting of custom animations of simulation results. We also have online animations of r- process, rp-process, and neutrino-p process element synthesis occurring in stellar explosions.

Anomaly detection applied to a materials control and accounting database

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whiteson, R.; Spanks, L.; Yarbro, T.

An important component of the national mission of reducing the nuclear danger includes accurate recording of the processing and transportation of nuclear materials. Nuclear material storage facilities, nuclear chemical processing plants, and nuclear fuel fabrication facilities collect and store large amounts of data describing transactions that involve nuclear materials. To maintain confidence in the integrity of these data, it is essential to identify anomalies in the databases. Anomalous data could indicate error, theft, or diversion of material. Yet, because of the complex and diverse nature of the data, analysis and evaluation are extremely tedious. This paper describes the authors workmore » in the development of analysis tools to automate the anomaly detection process for the Material Accountability and Safeguards System (MASS) that tracks and records the activities associated with accountable quantities of nuclear material at Los Alamos National Laboratory. Using existing guidelines that describe valid transactions, the authors have created an expert system that identifies transactions that do not conform to the guidelines. Thus, this expert system can be used to focus the attention of the expert or inspector directly on significant phenomena.« less

78 FR 47012 - Developing Software Life Cycle Processes Used in Safety Systems of Nuclear Power Plants

Federal Register 2010, 2011, 2012, 2013, 2014

2013-08-02

... NUCLEAR REGULATORY COMMISSION [NRC-2012-0195] Developing Software Life Cycle Processes Used in... revised regulatory guide (RG), revision 1 of RG 1.173, ``Developing Software Life Cycle Processes for... Developing a Software Project Life Cycle Process,'' issued 2006, with the clarifications and exceptions as...

Nuclear Technology Series. Course 14: Introduction to Quality Assurance/Quality Control.

ERIC Educational Resources Information Center

Technical Education Research Center, Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

Nuclear Technology Series. Course 6: Instrumentation and Control of Reactors and Plant Systems.

ERIC Educational Resources Information Center

Center for Occupational Research and Development, Inc., Waco, TX.

This technical specialty course is one of thirty-five courses designed for use by two-year postsecondary institutions in five nuclear technician curriculum areas: (1) radiation protection technician, (2) nuclear instrumentation and control technician, (3) nuclear materials processing technician, (4) nuclear quality-assurance/quality-control…

A Theoretical Approach to the Calculation of Annealed Impurity Profiles of Ion Implanted Boron into Silicon.

DTIC Science & Technology

1977-06-01

determined experimentally) and the distribution of energy deposited into nuclear processes by the boron ions. Damage is a product of this energy distri...energy deposited into nuclear processes, k is a constant adjusted to produce the total number of vacancies calculated in Fig. 11, and Tda m in the...profile computed from the energy depos- ited into nuclear processes = time constant for the release of vacancies fr( ,-, vacancy 1.- t ers C (liilibriul

Recent advances in nuclear magnetic resonance quantum information processing.

PubMed

Criger, Ben; Passante, Gina; Park, Daniel; Laflamme, Raymond

2012-10-13

Quantum information processors have the potential to drastically change the way we communicate and process information. Nuclear magnetic resonance (NMR) has been one of the first experimental implementations of quantum information processing (QIP) and continues to be an excellent testbed to develop new QIP techniques. We review the recent progress made in NMR QIP, focusing on decoupling, pulse engineering and indirect nuclear control. These advances have enhanced the capabilities of NMR QIP, and have useful applications in both traditional NMR and other QIP architectures.

Rydberg phases of Hydrogen and low energy nuclear reactions

NASA Astrophysics Data System (ADS)

Olafsson, Sveinn; Holmlid, Leif

2016-03-01

For over the last 26 years the science of cold fusion/LENR has been researched around the world with slow pace of progress. Modest quantity of excess heat and signatures of nuclear transmutation and helium production have been confirmed in experiments and theoretical work has only resulted in a large flora of inadequate theoretical scenarios. Here we review current state of research in Rydberg matter of Hydrogen that is showing strong signature of nuclear processes. In the presentation experimental behavior of Rydberg matter of hydrogen is described. An extensive collaboration effort of surface physics, catalysis, atomic physics, solid state physics, nuclear physics and quantum information is need to tackle the surprising experimental results that have so far been obtained. Rydberg matter of Hydrogen is the only known state of matter that is able to bring huge collection of protons to so short distances and for so long time that tunneling becomes a reasonable process for making low energy nuclear reactions. Nuclear quantum entanglement can also become realistic process at theses conditions.

Dual personality of Mad1: regulation of nuclear import by a spindle assembly checkpoint protein.

PubMed

Cairo, Lucas V; Ptak, Christopher; Wozniak, Richard W

2013-01-01

Nuclear transport is a dynamic process that can be modulated in response to changes in cellular physiology. We recently reported that the transport activity of yeast nuclear pore complexes (NPCs) is altered in response to kinetochore-microtubule (KT-MT) interaction defects. Specifically, KT detachment from MTs activates a signaling pathway that prevents the nuclear import of cargos by the nuclear transport factor Kap121p. This loss of Kap121p-mediated import is thought to influence the nuclear environment, including the phosphorylation state of nuclear proteins. A key regulator of this process is the spindle assembly checkpoint protein Mad1p. In response to unattached KTs, Mad1p dynamically cycles between NPCs and KTs. This cycling appears to induce NPC molecular rearrangements that prevent the nuclear import of Kap121p-cargo complexes. Here, we discuss the underlying mechanisms and the physiological relevance of Mad1p cycling and the inhibition of Kap121p-mediated nuclear import, focusing on outstanding questions within the pathway.

Double Charge Exchange Reactions and Double Beta Decay

NASA Astrophysics Data System (ADS)

Auerbach, N.

2018-05-01

The subject of this presentation is at the forefront of nuclear physics, namely double beta decay. In particular one is most interested in the neutrinoless process of double beta decay, when the decay proceeds without the emission of two neutrinos. The observation of such decay would mean that the lepton conservation symmetry is violated and that the neutrinos are of Majorana type, meaning that they are their own anti-particles. The life time of this process has two unknowns, the mass of the neutrino and the nuclear matrix element. Determining the nuclear matrix element and knowing the cross-section well will set limits on the neutrino mass. There is a concentrated effort among the nuclear physics community to calculate this matrix element. Usually these matrix elements are a very small part of the total strength of the transition operators involved in the process. There is no simple way to “calibrate” the nuclear double beta decay matrix element. The double beta decay is a double charge exchange process, therefore it is proposed that double charge exchange reactions using ion projectiles on nuclei that are candidates for double beta decay, will provide additional necessary information about the nuclear matrix elements.

An emerging link between LIM domain proteins and nuclear receptors.

PubMed

Sala, Stefano; Ampe, Christophe

2018-06-01

Nuclear receptors are ligand-activated transcription factors that partake in several biological processes including development, reproduction and metabolism. Over the last decade, evidence has accumulated that group 2, 3 and 4 LIM domain proteins, primarily known for their roles in actin cytoskeleton organization, also partake in gene transcription regulation. They shuttle between the cytoplasm and the nucleus, amongst other as a consequence of triggering cells with ligands of nuclear receptors. LIM domain proteins act as important coregulators of nuclear receptor-mediated gene transcription, in which they can either function as coactivators or corepressors. In establishing interactions with nuclear receptors, the LIM domains are important, yet pleiotropy of LIM domain proteins and nuclear receptors frequently occurs. LIM domain protein-nuclear receptor complexes function in diverse physiological processes. Their association is, however, often linked to diseases including cancer.

Nuclear forensics: Soil content

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beebe, Merilyn Amy

Nuclear Forensics is a growing field that is concerned with all stages of the process of creating and detonating a nuclear weapon. The main goal is to prevent nuclear attack by locating and securing nuclear material before it can be used in an aggressive manner. This stage of the process is mostly paperwork; laws, regulations, treaties, and declarations made by individual countries or by the UN Security Council. There is some preliminary leg work done in the form of field testing detection equipment and tracking down orphan materials; however, none of these have yielded any spectacular or useful results. Inmore » the event of a nuclear attack, the first step is to analyze the post detonation debris to aid in the identification of the responsible party. This aspect of the nuclear forensics process, while reactive in nature, is more scientific. A rock sample taken from the detonation site can be dissolved into liquid form and analyzed to determine its chemical composition. The chemical analysis of spent nuclear material can provide valuable information if properly processed and analyzed. In order to accurately evaluate the results, scientists require information on the natural occurring elements in the detonation zone. From this information, scientists can determine what percentage of the element originated in the bomb itself rather than the environment. To this end, element concentrations in soils from sixty-nine different cities are given, along with activity concentrations for uranium, thorium, potassium, and radium in various building materials. These data are used in the analysis program Python.« less

Impact of (α, n) reactions on weak r-process in neutrino-driven winds

NASA Astrophysics Data System (ADS)

Bliss, J.; Arcones, A.; Montes, F.; Pereira, J.

2017-05-01

After a successful core-collapse supernova, a neutrino-driven wind develops where it is possible to synthesize lighter heavy elements (30 < Z < 45). In the early galaxy, the origin of these elements is associated with the r-process and to an additional process. Here we assume that the additional process corresponds to the weak r-process (sometimes referred to as alpha-process) taking place in neutrino-driven winds. Based on a trajectory obtained from hydrodynamical simulations we study the astrophysics and nuclear physics uncertainties of a weak r-process with our main focus on the (α, n) reactions. These reactions are critical to redistribute the matter and allow it to move from light to heavy elements after nuclear statistical equilibrium freezes out. In this first sensitivity study, we vary all (α, n) reactions by given constant factors which are justified based on the uncertainties of the statistical model and its nuclear physics input, mainly alpha optical potentials for weak r-process conditions. Our results show that (α, n) rate uncertainties are indeed crucial to predict abundances. Therefore, further studies will follow to identify individual critical reactions. Since the nucleosynthesis path is close to stability, these reactions can be measured in the near future. Since much of the other nuclear data for the weak r-process are known, the reduction in nuclear physics uncertainties provided by these experiments will allow astronomical observations to directly constrain the astronomical conditions in the wind.

RNA Nuclear Export: From Neurological Disorders to Cancer.

PubMed

Hautbergue, Guillaume M

2017-01-01

The presence of a nuclear envelope, also known as nuclear membrane, defines the structural framework of all eukaryotic cells by separating the nucleus, which contains the genetic material, from the cytoplasm where the synthesis of proteins takes place. Translation of proteins in Eukaryotes is thus dependent on the active transport of DNA-encoded RNA molecules through pores embedded within the nuclear membrane. Several mechanisms are involved in this process generally referred to as RNA nuclear export or nucleocytoplasmic transport of RNA. The regulated expression of genes requires the nuclear export of protein-coding messenger RNA molecules (mRNAs) as well as non-coding RNAs (ncRNAs) together with proteins and pre-assembled ribosomal subunits. The nuclear export of mRNAs is intrinsically linked to the co-transcriptional processing of nascent transcripts synthesized by the RNA polymerase II. This functional coupling is essential for the survival of cells allowing for timely nuclear export of fully processed transcripts, which could otherwise cause the translation of abnormal proteins such as the polymeric repeat proteins produced in some neurodegenerative diseases. Alterations of the mRNA nuclear export pathways can also lead to genome instability and to various forms of cancer. This chapter will describe the molecular mechanisms driving the nuclear export of RNAs with a particular emphasis on mRNAs. It will also review their known alterations in neurological disorders and cancer, and the recent opportunities they offer for the potential development of novel therapeutic strategies.

Nuclear Export of Messenger RNA

PubMed Central

Katahira, Jun

2015-01-01

Transport of messenger RNA (mRNA) from the nucleus to the cytoplasm is an essential step of eukaryotic gene expression. In the cell nucleus, a precursor mRNA undergoes a series of processing steps, including capping at the 5' ends, splicing and cleavage/polyadenylation at the 3' ends. During this process, the mRNA associates with a wide variety of proteins, forming a messenger ribonucleoprotein (mRNP) particle. Association with factors involved in nuclear export also occurs during transcription and processing, and thus nuclear export is fully integrated into mRNA maturation. The coupling between mRNA maturation and nuclear export is an important mechanism for providing only fully functional and competent mRNA to the cytoplasmic translational machinery, thereby ensuring accuracy and swiftness of gene expression. This review describes the molecular mechanism of nuclear mRNA export mediated by the principal transport factors, including Tap-p15 and the TREX complex. PMID:25836925

Tracking of Nuclear Production using Indigenous Species: Final LDRD Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alam, Todd Michael; Alam, Mary Kathleen; McIntyre, Sarah K.

Our LDRD research project sought to develop an analytical method for detection of chemicals used in nuclear materials processing. Our approach is distinctly different than current research involving hardware-based sensors. By utilizing the response of indigenous species of plants and/or animals surrounding (or within) a nuclear processing facility, we propose tracking 'suspicious molecules' relevant to nuclear materials processing. As proof of concept, we have examined TBP, tributylphosphate, used in uranium enrichment as well as plutonium extraction from spent nuclear fuels. We will compare TBP to the TPP (triphenylphosphate) analog to determine the uniqueness of the metabonomic response. We show thatmore » there is a unique metabonomic response within our animal model to TBP. The TBP signature can further be delineated from that of TPP. We have also developed unique methods of instrumental transfer for metabonomic data sets.« less

Nuclear Functions of Actin

PubMed Central

Visa, Neus; Percipalle, Piergiorgio

2010-01-01

Actin participates in several essential processes in the cell nucleus. Even though the presence of actin in the nucleus was proposed more than 30 years ago, nuclear processes that require actin have been only recently identified. Actin is part of chromatin remodeling complexes; it is associated with the transcription machineries; it becomes incorporated into newly synthesized ribonucleoproteins; and it influences long-range chromatin organization. As in the cytoplasm, nuclear actin works in conjunction with different types of actin-binding proteins that regulate actin function and bridge interactions between actin and other nuclear components. PMID:20452941

TANGO: a generic tool for high-throughput 3D image analysis for studying nuclear organization.

PubMed

Ollion, Jean; Cochennec, Julien; Loll, François; Escudé, Christophe; Boudier, Thomas

2013-07-15

The cell nucleus is a highly organized cellular organelle that contains the genetic material. The study of nuclear architecture has become an important field of cellular biology. Extracting quantitative data from 3D fluorescence imaging helps understand the functions of different nuclear compartments. However, such approaches are limited by the requirement for processing and analyzing large sets of images. Here, we describe Tools for Analysis of Nuclear Genome Organization (TANGO), an image analysis tool dedicated to the study of nuclear architecture. TANGO is a coherent framework allowing biologists to perform the complete analysis process of 3D fluorescence images by combining two environments: ImageJ (http://imagej.nih.gov/ij/) for image processing and quantitative analysis and R (http://cran.r-project.org) for statistical processing of measurement results. It includes an intuitive user interface providing the means to precisely build a segmentation procedure and set-up analyses, without possessing programming skills. TANGO is a versatile tool able to process large sets of images, allowing quantitative study of nuclear organization. TANGO is composed of two programs: (i) an ImageJ plug-in and (ii) a package (rtango) for R. They are both free and open source, available (http://biophysique.mnhn.fr/tango) for Linux, Microsoft Windows and Macintosh OSX. Distribution is under the GPL v.2 licence. thomas.boudier@snv.jussieu.fr Supplementary data are available at Bioinformatics online.

Nuclear Chemistry: Include It in Your Curriculum.

ERIC Educational Resources Information Center

Atwood, Charles H.; Sheline, R. K.

1989-01-01

Some of the topics that might be included in a nuclear chemistry section are explored. Offers radioactivity, closed shells in nuclei, energy of nuclear processes, nuclear reactions, and fission and fusion as topics of interest. Provided are ideas and examples for each. (MVL)

The NJOY Nuclear Data Processing System, Version 2016

DOE Office of Scientific and Technical Information (OSTI.GOV)

Macfarlane, Robert; Muir, Douglas W.; Boicourt, R. M.

The NJOY Nuclear Data Processing System, version 2016, is a comprehensive computer code package for producing pointwise and multigroup cross sections and related quantities from evaluated nuclear data in the ENDF-4 through ENDF-6 legacy card-image formats. NJOY works with evaluated files for incident neutrons, photons, and charged particles, producing libraries for a wide variety of particle transport and reactor analysis codes.

Emerging Environmental Justice Issues in Nuclear Power and Radioactive Contamination.

PubMed

Kyne, Dean; Bolin, Bob

2016-07-12

Nuclear hazards, linked to both U.S. weapons programs and civilian nuclear power, pose substantial environment justice issues. Nuclear power plant (NPP) reactors produce low-level ionizing radiation, high level nuclear waste, and are subject to catastrophic contamination events. Justice concerns include plant locations and the large potentially exposed populations, as well as issues in siting, nuclear safety, and barriers to public participation. Other justice issues relate to extensive contamination in the U.S. nuclear weapons complex, and the mining and processing industries that have supported it. To approach the topic, first we discuss distributional justice issues of NPP sites in the U.S. and related procedural injustices in siting, operation, and emergency preparedness. Then we discuss justice concerns involving the U.S. nuclear weapons complex and the ways that uranium mining, processing, and weapons development have affected those living downwind, including a substantial American Indian population. Next we examine the problem of high-level nuclear waste and the risk implications of the lack of secure long-term storage. The handling and deposition of toxic nuclear wastes pose new transgenerational justice issues of unprecedented duration, in comparison to any other industry. Finally, we discuss the persistent risks of nuclear technologies and renewable energy alternatives.

Galvanic cell for processing of used nuclear fuel

DOEpatents

Garcia-Diaz, Brenda L.; Martinez-Rodriguez, Michael J.; Gray, Joshua R.; Olson, Luke C.

2017-02-07

A galvanic cell and methods of using the galvanic cell is described for the recovery of uranium from used nuclear fuel according to an electrofluorination process. The galvanic cell requires no input energy and can utilize relatively benign gaseous fluorinating agents. Uranium can be recovered from used nuclear fuel in the form of gaseous uranium compound such as uranium hexafluoride, which can then be converted to metallic uranium or UO.sub.2 and processed according to known methodology to form a useful product, e.g., fuel pellets for use in a commercial energy production system.

Electrochemical fluorination for processing of used nuclear fuel

DOEpatents

Garcia-Diaz, Brenda L.; Martinez-Rodriguez, Michael J.; Gray, Joshua R.; Olson, Luke C.

2016-07-05

A galvanic cell and methods of using the galvanic cell is described for the recovery of uranium from used nuclear fuel according to an electrofluorination process. The galvanic cell requires no input energy and can utilize relatively benign gaseous fluorinating agents. Uranium can be recovered from used nuclear fuel in the form of gaseous uranium compound such as uranium hexafluoride, which can then be converted to metallic uranium or UO.sub.2 and processed according to known methodology to form a useful product, e.g., fuel pellets for use in a commercial energy production system.

Hyperspectral recognition of processing tomato early blight based on GA and SVM

NASA Astrophysics Data System (ADS)

Yin, Xiaojun; Zhao, SiFeng

2013-03-01

Processing tomato early blight seriously affect the yield and quality of its.Determine the leaves spectrum of different disease severity level of processing tomato early blight.We take the sensitive bands of processing tomato early blight as support vector machine input vector.Through the genetic algorithm(GA) to optimize the parameters of SVM, We could recognize different disease severity level of processing tomato early blight.The result show:the sensitive bands of different disease severity levels of processing tomato early blight is 628-643nm and 689-692nm.The sensitive bands are as the GA and SVM input vector.We get the best penalty parameters is 0.129 and kernel function parameters is 3.479.We make classification training and testing by polynomial nuclear,radial basis function nuclear,Sigmoid nuclear.The best classification model is the radial basis function nuclear of SVM. Training accuracy is 84.615%,Testing accuracy is 80.681%.It is combined GA and SVM to achieve multi-classification of processing tomato early blight.It is provided the technical support of prediction processing tomato early blight occurrence, development and diffusion rule in large areas.

75 FR 66399 - FirstEnergy Nuclear Operating Company; Notice of Intent To Prepare an Environmental Impact...

Federal Register 2010, 2011, 2012, 2013, 2014

2010-10-28

... NUCLEAR REGULATORY COMMISSION [Docket No. 50-346; NRC-2010-0298] FirstEnergy Nuclear Operating Company; Notice of Intent To Prepare an Environmental Impact Statement and Conduct the Scoping Process for Davis-Besse Nuclear Power Station, Unit 1 FirstEnergy Nuclear Operating Company (FENOC) has submitted an application for renewal of Facility...

46 CFR 4.03-35 - Nuclear vessel.

Code of Federal Regulations, 2012 CFR

2012-10-01

... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2012-10-01 2012-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

46 CFR 4.03-35 - Nuclear vessel.

Code of Federal Regulations, 2013 CFR

2013-10-01

... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2013-10-01 2013-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

46 CFR 4.03-35 - Nuclear vessel.

Code of Federal Regulations, 2014 CFR

2014-10-01

... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2014-10-01 2014-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

46 CFR 4.03-35 - Nuclear vessel.

Code of Federal Regulations, 2010 CFR

2010-10-01

... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2010-10-01 2010-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

46 CFR 4.03-35 - Nuclear vessel.

Code of Federal Regulations, 2011 CFR

2011-10-01

... INVESTIGATIONS Definitions § 4.03-35 Nuclear vessel. The term nuclear vessel means any vessel in which power for propulsion, or for any other purpose, is derived from nuclear energy; or any vessel handling or processing... 46 Shipping 1 2011-10-01 2011-10-01 false Nuclear vessel. 4.03-35 Section 4.03-35 Shipping COAST...

Using NJOY to Create MCNP ACE Files and Visualize Nuclear Data

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kahler, Albert Comstock

We provide lecture materials that describe the input requirements to create various MCNP ACE files (Fast, Thermal, Dosimetry, Photo-nuclear and Photo-atomic) with the NJOY Nuclear Data Processing code system. Input instructions to visualize nuclear data with NJOY are also provided.

10 CFR 70.55 - Inspections.

Code of Federal Regulations, 2011 CFR

2011-01-01

... the case of fuel cycle facilities where nuclear reactor fuel is fabricated or processed each licensee... 10 Energy 2 2011-01-01 2011-01-01 false Inspections. 70.55 Section 70.55 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material Control...

10 CFR 70.55 - Inspections.

Code of Federal Regulations, 2012 CFR

2012-01-01

... the case of fuel cycle facilities where nuclear reactor fuel is fabricated or processed each licensee... 10 Energy 2 2012-01-01 2012-01-01 false Inspections. 70.55 Section 70.55 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material Control...

10 CFR 70.55 - Inspections.

Code of Federal Regulations, 2013 CFR

2013-01-01

... the case of fuel cycle facilities where nuclear reactor fuel is fabricated or processed each licensee... 10 Energy 2 2013-01-01 2013-01-01 false Inspections. 70.55 Section 70.55 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material Control...

10 CFR 70.55 - Inspections.

Code of Federal Regulations, 2010 CFR

2010-01-01

... the case of fuel cycle facilities where nuclear reactor fuel is fabricated or processed each licensee... 10 Energy 2 2010-01-01 2010-01-01 false Inspections. 70.55 Section 70.55 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material Control...

10 CFR 70.55 - Inspections.

Code of Federal Regulations, 2014 CFR

2014-01-01

... the case of fuel cycle facilities where nuclear reactor fuel is fabricated or processed each licensee... 10 Energy 2 2014-01-01 2014-01-01 false Inspections. 70.55 Section 70.55 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR MATERIAL Special Nuclear Material Control...

Binding blocks: building the Universe one nucleus at a time

NASA Astrophysics Data System (ADS)

Diget, C. Aa; Pastore, A.; Leech, K.; Haylett, T.; Lock, S.; Sanders, T.; Shelley, M.; Willett, H. V.; Keegans, J.; Sinclair, L.; Simpson, E. C.; Binding Blocks Collaboration

2017-03-01

We present a new teaching and outreach activity based around the construction of a three-dimensional chart of isotopes using \\text{LEG}{{\\text{O}}\\circledR} bricks5. The activity, binding blocks, demonstrates nuclear and astrophysical processes through a seven-meter chart of all nuclear isotopes, built from over 26 000 \\text{LEG}{{\\text{O}}\\circledR} bricks. It integrates A-Level and GCSE curricula across areas of nuclear physics, astrophysics, and chemistry, including: nuclear decays (through the colours in the chart); nuclear binding energy (through tower heights); production of chemical elements in the cosmos; fusion processes in stars and fusion energy on Earth; as well as links to medical physics, particularly diagnostics and radiotherapy.

Local negotiation on compensation siting of the spent nuclear fuel repository in Finland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kojo, Matti

The aim of the paper is to analyse the local negotiation process between the Municipality of Eurajoki and the nuclear power company Teollisuuden Voima (TVO) and the nuclear waste management company Posiva Oy. The aim of the negotiations was to find an acceptable form of compensation for siting a spent nuclear fuel repository in Olkiluoto, Finland. The paper includes background information on the siting process in Finland, the local political setting in the Municipality of Eurajoki and a description of the negotiation process. The analysis of the negotiations on compensation is important for better understanding the progress of the Finnishmore » siting process. The paper describes the picture of the contest to host the spent nuclear fuel repository. It also provides more information on the relationship between the Municipality of Eurajoki and the power company TVO. The negotiations on compensation and the roles of various players in the negotiations have not been studied in detail because the minutes of the Vuojoki liaison group were not available before the decision of the Supreme Administrative Court in May 2006. (author)« less

The design of photoelectric signal processing system for a nuclear magnetic resonance gyroscope based on FPGA

NASA Astrophysics Data System (ADS)

Zhang, Xian; Zhou, Binquan; Li, Hong; Zhao, Xinghua; Mu, Weiwei; Wu, Wenfeng

2017-10-01

Navigation technology is crucial to the national defense and military, which can realize the measurement of orientation, positioning, attitude and speed for moving object. Inertial navigation is not only autonomous, real-time, continuous, hidden, undisturbed but also no time-limited and environment-limited. The gyroscope is the core component of the inertial navigation system, whose precision and size are the bottleneck of the performance. However, nuclear magnetic resonance gyroscope is characteristic of the advantage of high precision and small size. Nuclear magnetic resonance gyroscope can meet the urgent needs of high-tech weapons and equipment development of new generation. This paper mainly designs a set of photoelectric signal processing system for nuclear magnetic resonance gyroscope based on FPGA, which process and control the information of detecting laser .The photoelectric signal with high frequency carrier is demodulated by in-phase and quadrature demodulation method. Finally, the processing system of photoelectric signal can compensate the residual magnetism of the shielding barrel and provide the information of nuclear magnetic resonance gyroscope angular velocity.

National Center for Nuclear Security: The Nuclear Forensics Project (F2012)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Klingensmith, A. L.

These presentation visuals introduce the National Center for Nuclear Security. Its chartered mission is to enhance the Nation’s verification and detection capabilities in support of nuclear arms control and nonproliferation through R&D activities at the NNSS. It has three focus areas: Treaty Verification Technologies, Nonproliferation Technologies, and Technical Nuclear Forensics. The objectives of nuclear forensics are to reduce uncertainty in the nuclear forensics process & improve the scientific defensibility of nuclear forensics conclusions when applied to nearsurface nuclear detonations. Research is in four key areas: Nuclear Physics, Debris collection and analysis, Prompt diagnostics, and Radiochemistry.

Ceramics in nuclear waste management

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chikalla, T D; Mendel, J E

1979-05-01

Seventy-three papers are included, arranged under the following section headings: national programs for the disposal of radioactive wastes, waste from stability and characterization, glass processing, ceramic processing, ceramic and glass processing, leaching of waste materials, properties of nuclear waste forms, and immobilization of special radioactive wastes. Separate abstracts were prepared for all the papers. (DLC)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goriely, S.; Bauswein, A.; Janka, H.-T.

About half of the nuclei heavier than iron observed in nature are produced by the so-called rapid neutron capture process, or r-process, of nucleosynthesis. The identification of the astrophysics site and the specific conditions in which the r-process takes place remains, however, one of the still-unsolved mysteries of modern astrophysics. Another underlying difficulty associated with our understanding of the r-process concerns the uncertainties in the predictions of nuclear properties for the few thousands exotic neutron-rich nuclei involved, for which essentially no experimental data exist. The present paper emphasizes some important future challenges faced by nuclear physics in this problem, particularlymore » in the determination of the nuclear structure properties of exotic neutron-rich nuclei as well as their radiative neutron capture rates and their fission probabilities. These quantities are particularly relevant to determine the composition of the matter resulting from the r-process. Both the astrophysics and the nuclear physics difficulties are critically reviewed with special attention paid to the r-process taking place during the decompression of neutron star matter following the merging of two neutron stars.« less

Investigation and Implementation of Commercially Available Optically Stimulated Luminescence Dosimeters for Use in Fixed Nuclear Accident Dosimeter Systems.

PubMed

Georgeson, David L; Christiansen, Byron H

2018-06-01

Idaho National Laboratory transitioned from an external dosimetry system reliant on thermoluminescent dosimeters to one that uses optically stimulated luminescence dosimeters in 2010. This change not only affected the dosimeters worn by personnel, but those found in the nuclear-accident dosimeters used across Idaho National Laboratory. The elimination of on-site use and processing of thermoluminescent dosimeters impacted Idaho National Laboratory's ability to process nuclear-accident dosimeters in a timely manner. This change in processes drove Idaho National Laboratory to develop an alternative method for fixed nuclear-accident dosimeter gamma-dose analyses. This new method was driven by the need to establish a simple, cost-effective, and rapid-turnaround alternative to the thermoluminescent-dosimeter-based fixed nuclear-accident dosimeter system. An adaptation of existing technologies proved to be the most efficient path to this end. The purpose of this article is to delineate the technical basis for replacing the thermoluminescent dosimeter contained within the Idaho National Laboratory fixed nuclear-accident dosimeter system with optically stimulated luminescence-based Landauer, Inc., nanoDot dosimeters.

A sensitivity study of s-process: the impact of uncertainties from nuclear reaction rates

NASA Astrophysics Data System (ADS)

Vinyoles, N.; Serenelli, A.

2016-01-01

The slow neutron capture process (s-process) is responsible for the production of about half the elements beyond the Fe-peak. The production sites and the conditions under which the different components of s-process occur are relatively well established. A detailed quantitative understanding of s-process nucleosynthesis may yield light in physical processes, e.g. convection and mixing, taking place in the production sites. For this, it is important that the impact of uncertainties in the nuclear physics is well understood. In this work we perform a study of the sensitivity of s-process nucleosynthesis, with particular emphasis in the main component, on the nuclear reaction rates. Our aims are: to quantify the current uncertainties in the production factors of s-process elements originating from nuclear physics and, to identify key nuclear reactions that require more precise experimental determinations. In this work we studied two different production sites in which s-process occurs with very different neutron exposures: 1) a low-mass extremely metal-poor star during the He-core flash (nn reaching up to values of ∼ 1014cm-3); 2) the TP-AGB phase of a M⊙, Z=0.01 model, the typical site of the main s-process component (nn up to 108 — 109cm-3). In the first case, the main variation in the production of s-process elements comes from the neutron poisons and with relative variations around 30%-50%. In the second, the neutron poison are not as important because of the higher metallicity of the star that actually acts as a seed and therefore, the final error of the abundances are much lower around 10%-25%.

Nuclear Technology: Making Informed Decisions.

ERIC Educational Resources Information Center

Altshuler, Kenneth

1989-01-01

Discusses a unit on nuclear technology which is taught in a physics class. Explains the unit design, implementation process, demonstrations used, and topics of discussion that include light and optics, naturally and artificially produced sources of radioactivity, nuclear equations, isotopes and half-lives, and power-generating nuclear reactors.…

Nuclear Enterprise Performance Measurement

DTIC Science & Technology

2011-03-01

xi I. Introduction ...WSA: Weapons Storage Area 1 I. Introduction Overview This paper discusses United States Air Force nuclear enterprise...sustainment systems. Keywords Performance measurement, process measurement, strategy, multicriteria decision- making, aggregation 1. Introduction Nuclear

76 FR 7592 - Entergy Nuclear Vermont Yankee, LLC and Entergy Nuclear Operations, Inc.; Notice of Issuance of...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-02-10

... completed to the Commission's satisfaction: (1) The tritiated groundwater remediation process; (2) the soil remediation process scheduled to take place during the refueling outage, to remove soil containing tritium and...

Introduction to Nuclear Physics (4/4)

ScienceCinema

Goutte, D.

2018-05-04

The last lecture of the summer student program devoted to nuclear physics. I'm going to talk about nuclear reaction and the fission process. There are two kinds of fission: spontaneous fission and induced fission.

The U.S. national nuclear forensics library, nuclear materials information program, and data dictionary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lamont, Stephen Philip; Brisson, Marcia; Curry, Michael

2011-02-17

Nuclear forensics assessments to determine material process history requires careful comparison of sample data to both measured and modeled nuclear material characteristics. Developing centralized databases, or nuclear forensics libraries, to house this information is an important step to ensure all relevant data will be available for comparison during a nuclear forensics analysis and help expedite the assessment of material history. The approach most widely accepted by the international community at this time is the implementation of National Nuclear Forensics libraries, which would be developed and maintained by individual nations. This is an attractive alternative toan international database since it providesmore » an understanding that each country has data on materials produced and stored within their borders, but eliminates the need to reveal any proprietary or sensitive information to other nations. To support the concept of National Nuclear Forensics libraries, the United States Department of Energy has developed a model library, based on a data dictionary, or set of parameters designed to capture all nuclear forensic relevant information about a nuclear material. Specifically, information includes material identification, collection background and current location, analytical laboratories where measurements were made, material packaging and container descriptions, physical characteristics including mass and dimensions, chemical and isotopic characteristics, particle morphology or metallurgical properties, process history including facilities, and measurement quality assurance information. While not necessarily required, it may also be valuable to store modeled data sets including reactor burn-up or enrichment cascade data for comparison. It is fully expected that only a subset of this information is available or relevant to many materials, and much of the data populating a National Nuclear Forensics library would be process analytical or material accountability measurement data as opposed to a complete forensic analysis of each material in the library.« less

The criteria of optimization of training specialists for the nuclear power industry and its implementation in the educational process

NASA Astrophysics Data System (ADS)

Lavrinenko, S. V.; Polikarpov, P. I.

2017-11-01

The nuclear industry is one of the most important and high-tech spheres of human activity in Russia. The main cause of accidents in the nuclear industry is the human factor. In this connection, the need to constantly analyze the system of training of specialists and its optimization in order to improve safety at nuclear industry enterprises. To do this, you must analyze the international experience in the field of training in the field of nuclear energy leading countries. Based on the analysis criteria have been formulated to optimize the educational process of training specialists for the nuclear power industry and test their effectiveness. The most effective and promising is the introduction of modern information technologies of training of students, such as real-time simulators, electronic educational resources, etc.

10 CFR 70.23 - Requirements for the approval of applications.

Code of Federal Regulations, 2014 CFR

2014-01-01

... and use special nuclear material in a plutonium processing and fuel fabrication plant. 3 The criteria... Section 70.23 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR... a license will be approved if the Commission determines that: (1) The special nuclear material is to...

10 CFR 70.23 - Requirements for the approval of applications.

Code of Federal Regulations, 2012 CFR

2012-01-01

... and use special nuclear material in a plutonium processing and fuel fabrication plant. 3 The criteria... Section 70.23 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR... a license will be approved if the Commission determines that: (1) The special nuclear material is to...

10 CFR 70.23 - Requirements for the approval of applications.

Code of Federal Regulations, 2011 CFR

2011-01-01

... to possess and use special nuclear material in a plutonium processing and fuel fabrication plant. 3... Section 70.23 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR... a license will be approved if the Commission determines that: (1) The special nuclear material is to...

10 CFR 70.23 - Requirements for the approval of applications.

Code of Federal Regulations, 2013 CFR

2013-01-01

... and use special nuclear material in a plutonium processing and fuel fabrication plant. 3 The criteria... Section 70.23 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) DOMESTIC LICENSING OF SPECIAL NUCLEAR... a license will be approved if the Commission determines that: (1) The special nuclear material is to...

Special nuclear materials cutoff exercise: Issues and lessons learned. Volume 3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Libby, R.A.; Segal, J.E.; Stanbro, W.D.

1995-08-01

This document is appendices D-J for the Special Nuclear Materials Cutoff Exercise: Issues and Lessons Learned. Included are discussions of the US IAEA Treaty, safeguard regulations for nuclear materials, issue sheets for the PUREX process, and the LANL follow up activity for reprocessing nuclear materials.

Production and testing of the ENEA-Bologna VITJEFF32.BOLIB (JEFF-3.2) multi-group (199 n + 42 γ) cross section library in AMPX format for nuclear fission applications

NASA Astrophysics Data System (ADS)

Pescarini, Massimo; Orsi, Roberto; Frisoni, Manuela

2017-09-01

The ENEA-Bologna Nuclear Data Group produced the VITJEFF32.BOLIB multi-group coupled neutron/photon (199 n + 42 γ) cross section library in AMPX format, based on the OECD-NEA Data Bank JEFF-3.2 evaluated nuclear data library. VITJEFF32.BOLIB was conceived for nuclear fission applications as European counterpart of the ORNL VITAMIN-B7 similar library (ENDF/B-VII.0 data). VITJEFF32.BOLIB has the same neutron and photon energy group structure as the former ORNL VITAMIN-B6 reference library (ENDF/B-VI.3 data) and was produced using similar data processing methodologies, based on the LANL NJOY-2012.53 nuclear data processing system for the generation of the nuclide cross section data files in GENDF format. Then the ENEA-Bologna 2007 Revision of the ORNL SCAMPI nuclear data processing system was used for the conversion into the AMPX format. VITJEFF32.BOLIB contains processed cross section data files for 190 nuclides, obtained through the Bondarenko (f-factor) method for the treatment of neutron resonance self-shielding and temperature effects. Collapsed working libraries of self-shielded cross sections in FIDO-ANISN format, used by the deterministic transport codes of the ORNL DOORS system, can be generated from VITJEFF32.BOLIB through the cited SCAMPI version. This paper describes the methodology and specifications of the data processing performed and presents some results of the VITJEFF32.BOLIB validation.

Canada's Deep Geological Repository for Used Nuclear Fuel - Geo-scientific Site Evaluation Process - 13117

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blyth, Alec; Ben Belfadhel, Mahrez; Hirschorn, Sarah

2013-07-01

The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management (APM), the approach selected by the Government of Canada for long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository in a suitable rock formation at a depth of approximately 500 meters (m) (1,640 feet [ft]). In May 2010, the NWMO published a nine-step site selection process that serves as the road map to decision-making on the location for the deep geological repository. The safetymore » and appropriateness of any potential site will be assessed against a number of factors, both technical and social in nature. The selected site will be one that can be demonstrated to be able to safely contain and isolate used nuclear fuel, protecting humans and the environment over the very long term. The geo-scientific suitability of potential candidate sites will be assessed in a stepwise manner following a progressive and thorough site evaluation process that addresses a series of geo-scientific factors revolving around five safety functions. The geo-scientific site evaluation process includes: Initial Screenings; Preliminary Assessments; and Detailed Site Evaluations. As of November 2012, 22 communities have entered the site selection process (three in northern Saskatchewan and 18 in northwestern and southwestern Ontario). (authors)« less

Electromagnetic Devices and Processes in Environment Protection: Post-Conference Materials.

DTIC Science & Technology

1994-09-09

the Response of Power Transmission and Distribution Lines to a Nuclear Detonation at a High Altitude" 5. R. Goleman, M. Pahczyk, M. Pawlot...processes are unfortunately endothermal ones. However, if necessary energy is produced via a C02-free way(e.g. using solar, hydro, wind, nuclear or...POST-CONFERENCE MATERIALS 31 DETERMINING THE RESPONSE OF POWER TRANSMISSION AND DISTRIBUTION LINES TO A NUCLEAR DETONATION AT A HIGH ALTITUDE

Minimum Nuclear Deterrence Postures in South Asia: An Overview

DTIC Science & Technology

2001-10-01

states in May 1998, India and Pakistan both espoused nuclear restraint. Their senior officials soon embraced the language of "minimum credible...Air Force and Army. India’s longer-range nuclear-capable missiles such as the Agni, however, are still in the research and development process under...explained in Appendix A, Pakistan continued between 1991 and 1998 to enrich uranium to low- enriched (LEU) levels. Since enrichment is an iterative process

Studies and research concerning BNFP: computerized nuclear materials control and accounting system development evaluation report, FY 1978

DOE Office of Scientific and Technical Information (OSTI.GOV)

Crawford, J M; Ehinger, M H; Joseph, C

1978-10-01

Development work on a computerized system for nuclear materials control and accounting in a nuclear fuel reprocessing plant is described and evaluated. Hardware and software were installed and tested to demonstrate key measurement, measurement control, and accounting requirements at accountability input/output points using natural uranium. The demonstration included a remote data acquisition system which interfaces process and special instrumentation to a cenral processing unit.

ALL-UNION CONFERENCE ON APPLICATIONS OF RADIOACTIVE ISOTOPES AND NUCLEAR EMISSIONS IN THE NATIONAL INDUSTRY OF USSR (in Russian)

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

1960-09-01

Papers presented at the All-Union Conference on Industrial Applications of Radioactive Isotopes and Nuclear Emissions in the National Economy of USSR, April 12 to 16, 1960, in Riga are surveyed. Short summaries are given on applications of radioactive isotopes and nuclear emissions in prospecting, developing mineral resources, metallurgy, ore enrichment processes, machine construction technology, agriculture, food processing, and medicine. Sources of alpha , beta , and gamma radiation for control and automation of processes are also discussed. The full reports from the conference will be published in 1960. (R.V.J.)

Cycling the hot CNO: a teaching methodology

NASA Astrophysics Data System (ADS)

Frost-Schenk, J. W.; Diget, C. Aa; Bentley, M. A.; Tuff, A.

2018-03-01

An interactive activity to teach the hot Carbon, Nitrogen and Oxygen (HCNO) cycle is proposed. Justification for why the HCNO cycle is important is included via an example of x-ray bursts. The activity allows teaching and demonstration of half-life, nuclear isotopes, nuclear reactions, protons and α-particles, and catalytic processes. Whilst the process example is specific to astrophysics it may be used to teach more broadly about catalytic processes. This practical is designed for use with 10-20 participants, with the intention that the exercise will convey nuclear physics principles in a fun and interactive manner.

Uncertainties in s -process nucleosynthesis in low mass stars determined from Monte Carlo variations

NASA Astrophysics Data System (ADS)

Cescutti, G.; Hirschi, R.; Nishimura, N.; den Hartogh, J. W.; Rauscher, T.; Murphy, A. St J.; Cristallo, S.

2018-05-01

The main s-process taking place in low mass stars produces about half of the elements heavier than iron. It is therefore very important to determine the importance and impact of nuclear physics uncertainties on this process. We have performed extensive nuclear reaction network calculations using individual and temperature-dependent uncertainties for reactions involving elements heavier than iron, within a Monte Carlo framework. Using this technique, we determined the uncertainty in the main s-process abundance predictions due to nuclear uncertainties link to weak interactions and neutron captures on elements heavier than iron. We also identified the key nuclear reactions dominating these uncertainties. We found that β-decay rate uncertainties affect only a few nuclides near s-process branchings, whereas most of the uncertainty in the final abundances is caused by uncertainties in neutron capture rates, either directly producing or destroying the nuclide of interest. Combined total nuclear uncertainties due to reactions on heavy elements are in general small (less than 50%). Three key reactions, nevertheless, stand out because they significantly affect the uncertainties of a large number of nuclides. These are 56Fe(n,γ), 64Ni(n,γ), and 138Ba(n,γ). We discuss the prospect of reducing uncertainties in the key reactions identified in this study with future experiments.

Emerging Environmental Justice Issues in Nuclear Power and Radioactive Contamination

PubMed Central

Kyne, Dean; Bolin, Bob

2016-01-01

Nuclear hazards, linked to both U.S. weapons programs and civilian nuclear power, pose substantial environment justice issues. Nuclear power plant (NPP) reactors produce low-level ionizing radiation, high level nuclear waste, and are subject to catastrophic contamination events. Justice concerns include plant locations and the large potentially exposed populations, as well as issues in siting, nuclear safety, and barriers to public participation. Other justice issues relate to extensive contamination in the U.S. nuclear weapons complex, and the mining and processing industries that have supported it. To approach the topic, first we discuss distributional justice issues of NPP sites in the U.S. and related procedural injustices in siting, operation, and emergency preparedness. Then we discuss justice concerns involving the U.S. nuclear weapons complex and the ways that uranium mining, processing, and weapons development have affected those living downwind, including a substantial American Indian population. Next we examine the problem of high-level nuclear waste and the risk implications of the lack of secure long-term storage. The handling and deposition of toxic nuclear wastes pose new transgenerational justice issues of unprecedented duration, in comparison to any other industry. Finally, we discuss the persistent risks of nuclear technologies and renewable energy alternatives. PMID:27420080

A Role for Myosin Va in Human Cytomegalovirus Nuclear Egress.

PubMed

Wilkie, Adrian R; Sharma, Mayuri; Pesola, Jean M; Ericsson, Maria; Fernandez, Rosio; Coen, Donald M

2018-03-15

Herpesviruses replicate and package their genomes into capsids in replication compartments within the nuclear interior. Capsids then move to the inner nuclear membrane for envelopment and release into the cytoplasm in a process called nuclear egress. We previously found that nuclear F-actin is induced upon infection with the betaherpesvirus human cytomegalovirus (HCMV) and is important for nuclear egress and capsid localization away from replication compartment-like inclusions toward the nuclear rim. Despite these and related findings, it has not been shown that any specific motor protein is involved in herpesvirus nuclear egress. In this study, we have investigated whether the host motor protein, myosin Va, could be fulfilling this role. Using immunofluorescence microscopy and coimmunoprecipitation, we observed associations between a nuclear population of myosin Va and the viral major capsid protein, with both concentrating at the periphery of replication compartments. Immunoelectron microscopy showed that nearly 40% of assembled nuclear capsids associate with myosin Va. We also found that myosin Va and major capsid protein colocalize with nuclear F-actin. Importantly, antagonism of myosin Va with RNA interference or a dominant negative mutant revealed that myosin Va is important for the efficient production of infectious virus, capsid accumulation in the cytoplasm, and capsid localization away from replication compartment-like inclusions toward the nuclear rim. Our results lead us to suggest a working model whereby human cytomegalovirus capsids associate with myosin Va for movement from replication compartments to the nuclear periphery during nuclear egress. IMPORTANCE Little is known regarding how newly assembled and packaged herpesvirus capsids move from the nuclear interior to the periphery during nuclear egress. While it has been proposed that an actomyosin-based mechanism facilitates intranuclear movement of alphaherpesvirus capsids, a functional role for any specific myosin in nuclear egress has not been reported. Furthermore, the notion that an actomyosin-based mechanism facilitates intranuclear capsid movement is controversial. Here we show that human cytomegalovirus capsids associate with nuclear myosin Va and F-actin and that antagonism of myosin Va impairs capsid localization toward the nuclear rim and nuclear egress. Together with our previous results showing that nuclear F-actin is induced upon HCMV infection and is also important for these processes, our results lend support to the hypothesis that nascent human cytomegalovirus capsids migrate to the nuclear periphery via actomyosin-based movement. These results shed light on a poorly understood viral process and the cellular machinery involved. Copyright © 2018 American Society for Microbiology.

Qualification of submerged-arc narrow strip cladding process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ayres, P.S.; Gottschling, J.D.; Jeffers, G.K.

1975-08-01

An unique narrow strip cladding process for use on both plate and forging material for nuclear components was developed. The qualification testing of this low-heat input process for cladding nuclear components, including those of SA508 Class 2 material is described. The theory that explains the acceptable results of these tests is also given. (auth)

Qualification of submerged-arc narrow strip cladding process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ayres, P.S.; Gottschling, J.D.; Jeffers, G.K.

1976-03-01

Babcock and Wilcox has developed an unique narrow strip cladding process for use on both plate and forging material for nuclear components. The qualification testing of this low-heat input process for cladding nuclear components is described, including those of SA508 Class 2 material. The theory that explains the acceptable results of these tests is also given.

The Tokaimura Nuclear Accident: A Tragedy of Human Errors.

ERIC Educational Resources Information Center

Ryan, Michael E.

2001-01-01

Discusses nuclear power and the consequences of a nuclear accident. Covers issues ranging from chemical process safety to risk management of chemical industries to the ethical responsibilities of the chemical engineer. (Author/ASK)

Laboratory Astrophysics Prize: Laboratory Astrophysics with Nuclei

NASA Astrophysics Data System (ADS)

Wiescher, Michael

2018-06-01

Nuclear astrophysics is concerned with nuclear reaction and decay processes from the Big Bang to the present star generation controlling the chemical evolution of our universe. Such nuclear reactions maintain stellar life, determine stellar evolution, and finally drive stellar explosion in the circle of stellar life. Laboratory nuclear astrophysics seeks to simulate and understand the underlying processes using a broad portfolio of nuclear instrumentation, from reactor to accelerator from stable to radioactive beams to map the broad spectrum of nucleosynthesis processes. This talk focuses on only two aspects of the broad field, the need of deep underground accelerator facilities in cosmic ray free environments in order to understand the nucleosynthesis in stars, and the need for high intensity radioactive beam facilities to recreate the conditions found in stellar explosions. Both concepts represent the two main frontiers of the field, which are being pursued in the US with the CASPAR accelerator at the Sanford Underground Research Facility in South Dakota and the FRIB facility at Michigan State University.

Natural analogues of nuclear waste glass corrosion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

1999-01-06

This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information availablemore » on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses.« less

Local traction force in the proximal leading process triggers nuclear translocation during neuronal migration.

PubMed

Umeshima, Hiroki; Nomura, Ken-Ichi; Yoshikawa, Shuhei; Hörning, Marcel; Tanaka, Motomu; Sakuma, Shinya; Arai, Fumihito; Kaneko, Makoto; Kengaku, Mineko

2018-04-05

Somal translocation in long bipolar neurons is regulated by actomyosin contractile forces, yet the precise spatiotemporal sites of force generation are unknown. Here we investigate the force dynamics generated during somal translocation using traction force microscopy. Neurons with a short leading process generated a traction force in the growth cone and counteracting forces in the leading and trailing processes. In contrast, neurons with a long leading process generated a force dipole with opposing traction forces in the proximal leading process during nuclear translocation. Transient accumulation of actin filaments was observed at the dipole center of the two opposing forces, which was abolished by inhibition of myosin II activity. A swelling in the leading process emerged and generated a traction force that pulled the nucleus when nuclear translocation was physically hampered. The traction force in the leading process swelling was uncoupled from somal translocation in neurons expressing a dominant negative mutant of the KASH protein, which disrupts the interaction between cytoskeletal components and the nuclear envelope. Our results suggest that the leading process is the site of generation of actomyosin-dependent traction force in long bipolar neurons, and that the traction force is transmitted to the nucleus via KASH proteins. Copyright © 2018 Elsevier B.V. and Japan Neuroscience Society. All rights reserved.

Fission in R-processes Elements (FIRE) - Annual Report: Fiscal Year 2017

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schunck, Nicolas

The goal of the FIRE topical collaboration in nuclear theory is to determine the astrophysical conditions of the rapid neutron capture process (r-process), which is responsible for the formation of heavy elements. This will be achieved by including in r-process simulations the most advanced models of fission (spontaneous, neutron-induced, beta-delayed) that have been developed at LLNL and LANL. The collaboration is composed of LLNL (lead) and LANL for work on nuclear data (ground-state properties, fission, beta-decay), BNL for nuclear data management, and the university of Notre Dame and North Carolina State University for r-process simulations. Under DOE/NNSA agreement, both universitiesmore » receive funds from the DOE Office of Science, while national laboratories receive funds directly from NA221.« less

Computer programs of information processing of nuclear physical methods as a demonstration material in studying nuclear physics and numerical methods

NASA Astrophysics Data System (ADS)

Bateev, A. B.; Filippov, V. P.

2017-01-01

The principle possibility of using computer program Univem MS for Mössbauer spectra fitting as a demonstration material at studying such disciplines as atomic and nuclear physics and numerical methods by students is shown in the article. This program is associated with nuclear-physical parameters such as isomer (or chemical) shift of nuclear energy level, interaction of nuclear quadrupole moment with electric field and of magnetic moment with surrounded magnetic field. The basic processing algorithm in such programs is the Least Square Method. The deviation of values of experimental points on spectra from the value of theoretical dependence is defined on concrete examples. This value is characterized in numerical methods as mean square deviation. The shape of theoretical lines in the program is defined by Gaussian and Lorentzian distributions. The visualization of the studied material on atomic and nuclear physics can be improved by similar programs of the Mössbauer spectroscopy, X-ray Fluorescence Analyzer or X-ray diffraction analysis.

Energy Conversion Loop: A Testbed for Nuclear Hybrid Energy Systems Use in Biomass Pyrolysis

NASA Astrophysics Data System (ADS)

Verner, Kelley M.

Nuclear hybrid energy systems are a possible solution for contemporary energy challenges. Nuclear energy produces electricity without greenhouse gas emissions. However, nuclear power production is not as flexible as electrical grids demand and renewables create highly variable electricity. Nuclear hybrid energy systems are able to address both of these problems. Wasted heat can be used in processes such as desalination, hydrogen production, or biofuel production. This research explores the possible uses of nuclear process heat in bio-oil production via biomass pyrolysis. The energy conversion loop is a testbed designed and built to mimic the heat from a nuclear reactor. Small scale biomass pyrolysis experiments were performed and compared to results from the energy conversion loop tests to determine future pyrolysis experimentation with the energy conversion loop. Further improvements must be made to the energy conversion loop before more complex experiments may be performed. The current conditions produced by the energy conversion loop are not conducive for current biomass pyrolysis experimentation.tion.

[Compartmentalization of the cell nucleus and spatial organization of the genome].

PubMed

Gavrilov, A A; Razin, S V

2015-01-01

The eukaryotic cell nucleus is one of the most complex cell organelles. Despite the absence of membranes, the nuclear space is divided into numerous compartments where different processes in- volved in the genome activity take place. The most important nuclear compartments include nucleoli, nuclear speckles, PML bodies, Cajal bodies, histone locus bodies, Polycomb bodies, insulator bodies, transcription and replication factories. The structural basis for the nuclear compartmentalization is provided by genomic DNA that occupies most of the nuclear volume. Nuclear compartments, in turn, guide the chromosome folding by providing a platform for the spatial interaction of individual genomic loci. In this review, we discuss fundamental principles of higher order genome organization with a focus on chromosome territories and chromosome domains, as well as consider the structure and function of the key nuclear compartments. We show that the func- tional compartmentalization of the cell nucleus and genome spatial organization are tightly interconnected, and that this form of organization is highly dynamic and is based on stochastic processes.

Uranium to Electricity: The Chemistry of the Nuclear Fuel Cycle

ERIC Educational Resources Information Center

Settle, Frank A.

2009-01-01

The nuclear fuel cycle consists of a series of industrial processes that produce fuel for the production of electricity in nuclear reactors, use the fuel to generate electricity, and subsequently manage the spent reactor fuel. While the physics and engineering of controlled fission are central to the generation of nuclear power, chemistry…

Scoping Study of Machine Learning Techniques for Visualization and Analysis of Multi-source Data in Nuclear Safeguards

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cui, Yonggang

In implementation of nuclear safeguards, many different techniques are being used to monitor operation of nuclear facilities and safeguard nuclear materials, ranging from radiation detectors, flow monitors, video surveillance, satellite imagers, digital seals to open source search and reports of onsite inspections/verifications. Each technique measures one or more unique properties related to nuclear materials or operation processes. Because these data sets have no or loose correlations, it could be beneficial to analyze the data sets together to improve the effectiveness and efficiency of safeguards processes. Advanced visualization techniques and machine-learning based multi-modality analysis could be effective tools in such integratedmore » analysis. In this project, we will conduct a survey of existing visualization and analysis techniques for multi-source data and assess their potential values in nuclear safeguards.« less

Python-Based Tool for Universal Nuclear Data Extraction

NASA Astrophysics Data System (ADS)

McDonald, William; Blair, Hayden; Consalvi, Peter; Garbiso, Markus; Grover, Hannah; Harget, Alex; Martin, Matthew; Natzke, Connor; Leach, Kyle

2017-09-01

Over the past 70 years, nuclear physics experiments have provided a vast wealth of experimental data on both ground and excited state properties across the nuclear chart. In many cases, searching for and parsing the relevant nuclear structure data from previous work can be tedious and difficult. Although the compilation, evaluation, and digitization of this data by multiple groups around the world over the past several decades has helped dramatically in this respect, the process of performing systematic studies using this data can still be cumbersome and limited. We are in the process of creating a python-based program to extract, sort, and manipulate nuclear and atomic data efficiently. In its current state, the program is able to extract all atomic-shell ionization energies, excited- and ground-state nuclear properties, and all beta-decay rates and ratios. As a part of this ongoing project, we plan to use this tool to examine beta-decay rates in extreme astrophysical environments.

γ-radiation of excited nuclear discrete levels in peripheral heavy ion collisions

NASA Astrophysics Data System (ADS)

Korotkikh, V. L.; Chikin, K. A.

A new process of a nuclear excitation to discrete states in peripheral heavy ion collisions is studied. High-energy photons are emitted by the exited nuclei with energies up to a few tens of GeV at angles of a few hundred microradians with respect to the beam direction. We show that a two-stage process, where an electron-positron pair is produced by virtual photons emitted by nuclei and then the electron or positron excites the nucleus, has a large cross-section. It is equal to about 5 b for CaCa collisions. On the one hand, it produces a significant γ-rays background in the nuclear fragmentation region but, on the other hand, it could be used for monitoring the nuclear beam intensity at the LHC. These secondary nuclear photons could be a good signal for triggering peripheral nuclear collisions.

Spallation processes and nuclear interaction products of cosmic rays.

PubMed

Silberberg, R; Tsao, C H

1990-08-01

Most cosmic-ray nuclei heavier than helium have suffered nuclear collisions in the interstellar gas, with transformation of nuclear composition. The isotopic and elemental composition at the sources has to be inferred from the observed composition near the Earth. The source composition permits tests of current ideas on sites of origin, nucleosynthesis in stars, evolution of stars, the mixing and composition of the interstellar medium and injection processes prior to acceleration. The effects of nuclear spallation, production of radioactive nuclides and the time dependence of their decay provide valuable information on the acceleration and propagation of cosmic rays, their nuclear transformations, and their confinement time in the Galaxy. The formation of spallation products that only decay by electron capture and are relatively long-lived permits an investigation of the nature and density fluctuations (like clouds) of the interstellar medium. Since nuclear collisions yield positrons, antiprotons, gamma rays and neutrinos, we shall discuss these topics briefly.

Capture and photonuclear reaction rates involving charged-particles: Impacts of nuclear ingredients and future measurement on ELI-NP

NASA Astrophysics Data System (ADS)

Xu, Y.; Goriely, S.; Balabanski, D. L.; Chesnevskaya, S.; Guardo, G. L.; La Cognata, M.; Lan, H. Y.; Lattuada, D.; Luo, W.; Matei, C.

2018-05-01

The astrophysical p-process is an important way of nucleosynthesis to produce the stable and proton-rich nuclei beyond Fe which can not be reached by the s- and r-processes. In the present study, the impact of nuclear ingredients, especially the nuclear potential, level density and strength function, to the astrophysical re-action rates of (p,γ), (α,γ), (γ,p), and (γ,α) reactions are systematically studied. The calculations are performed basad on the modern reaction code TALYS for about 3000 stable and proton-rich nuclei with 12≤Z≤110. In particular, both of the Wood-Saxon potential and the microscopic folding potential are taken into account. It is found that both the capture and photonuclear reaction rates are very sensitive to the nuclear potential, thus the better determination of nuclear potential would be important to reduce the uncertainties of reaction rates. Meanwhile, the Extreme Light Infrastructure-Nuclear Physics (ELI-NP) facility is being developed, which will provide the great opportunity to experimentally study the photonuclear reactions in p-process. Simulations of the experimental setup for the measurements of the photonuclear reactions 96Ru(γ,p) and 96Ru(γ,α) are performed. It is shown that the experiments of photonuclear reactions in p-process based on ELI-NP are quite promising.

Savannah River Site Spent Nuclear Fuel Management Final Environmental Impact Statement

DOE Office of Scientific and Technical Information (OSTI.GOV)

N /A

The proposed DOE action considered in this environmental impact statement (EIS) is to implement appropriate processes for the safe and efficient management of spent nuclear fuel and targets at the Savannah River Site (SRS) in Aiken County, South Carolina, including placing these materials in forms suitable for ultimate disposition. Options to treat, package, and store this material are discussed. The material included in this EIS consists of approximately 68 metric tons heavy metal (MTHM) of spent nuclear fuel 20 MTHM of aluminum-based spent nuclear fuel at SRS, as much as 28 MTHM of aluminum-clad spent nuclear fuel from foreign andmore » domestic research reactors to be shipped to SRS through 2035, and 20 MTHM of stainless-steel or zirconium-clad spent nuclear fuel and some Americium/Curium Targets stored at SRS. Alternatives considered in this EIS encompass a range of new packaging, new processing, and conventional processing technologies, as well as the No Action Alternative. A preferred alternative is identified in which DOE would prepare about 97% by volume (about 60% by mass) of the aluminum-based fuel for disposition using a melt and dilute treatment process. The remaining 3% by volume (about 40% by mass) would be managed using chemical separation. Impacts are assessed primarily in the areas of water resources, air resources, public and worker health, waste management, socioeconomic, and cumulative impacts.« less

HYBRID SULFUR PROCESS REFERENCE DESIGN AND COST ANALYSIS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gorensek, M.; Summers, W.; Boltrunis, C.

2009-05-12

This report documents a detailed study to determine the expected efficiency and product costs for producing hydrogen via water-splitting using energy from an advanced nuclear reactor. It was determined that the overall efficiency from nuclear heat to hydrogen is high, and the cost of hydrogen is competitive under a high energy cost scenario. It would require over 40% more nuclear energy to generate an equivalent amount of hydrogen using conventional water-cooled nuclear reactors combined with water electrolysis compared to the proposed plant design described herein. There is a great deal of interest worldwide in reducing dependence on fossil fuels, whilemore » also minimizing the impact of the energy sector on global climate change. One potential opportunity to contribute to this effort is to replace the use of fossil fuels for hydrogen production by the use of water-splitting powered by nuclear energy. Hydrogen production is required for fertilizer (e.g. ammonia) production, oil refining, synfuels production, and other important industrial applications. It is typically produced by reacting natural gas, naphtha or coal with steam, which consumes significant amounts of energy and produces carbon dioxide as a byproduct. In the future, hydrogen could also be used as a transportation fuel, replacing petroleum. New processes are being developed that would permit hydrogen to be produced from water using only heat or a combination of heat and electricity produced by advanced, high temperature nuclear reactors. The U.S. Department of Energy (DOE) is developing these processes under a program known as the Nuclear Hydrogen Initiative (NHI). The Republic of South Africa (RSA) also is interested in developing advanced high temperature nuclear reactors and related chemical processes that could produce hydrogen fuel via water-splitting. This report focuses on the analysis of a nuclear hydrogen production system that combines the Pebble Bed Modular Reactor (PBMR), under development by PBMR (Pty.) Ltd. in the RSA, with the Hybrid Sulfur (HyS) Process, under development by the Savannah River National Laboratory (SRNL) in the US as part of the NHI. This work was performed by SRNL, Westinghouse Electric Company, Shaw, PBMR (Pty) Ltd., and Technology Insights under a Technical Consulting Agreement (TCA). Westinghouse Electric, serving as the lead for the PBMR process heat application team, established a cost-shared TCA with SRNL to prepare an updated HyS thermochemical water-splitting process flowsheet, a nuclear hydrogen plant preconceptual design and a cost estimate, including the cost of hydrogen production. SRNL was funded by DOE under the NHI program, and the Westinghouse team was self-funded. The results of this work are presented in this Final Report. Appendices have been attached to provide a detailed source of information in order to document the work under the TCA contract.« less

Theory of Neutron Chain Reactions: Extracts from Volume I, Diffusion and Slowing Down of Neutrons: Chapter I. Elementary Theory of Neutron Diffusion. Chapter II. Second Order Diffusion Theory. Chapter III. Slowing Down of Neutrons

DOE R&D Accomplishments Database

Weinberg, Alvin M.; Noderer, L. C.

1951-05-15

The large scale release of nuclear energy in a uranium fission chain reaction involves two essentially distinct physical phenomena. On the one hand there are the individual nuclear processes such as fission, neutron capture, and neutron scattering. These are essentially quantum mechanical in character, and their theory is non-classical. On the other hand, there is the process of diffusion -- in particular, diffusion of neutrons, which is of fundamental importance in a nuclear chain reaction. This process is classical; insofar as the theory of the nuclear chain reaction depends on the theory of neutron diffusion, the mathematical study of chain reactions is an application of classical, not quantum mechanical, techniques.

Trends in Nuclear Explosion Monitoring Research & Development - A Physics Perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Maceira, Monica; Blom, Philip Stephen; MacCarthy, Jonathan K.

This document entitled “Trends in Nuclear Explosion Monitoring Research and Development – A Physics Perspective” reviews the accessible literature, as it relates to nuclear explosion monitoring and the Comprehensive Nuclear-Test-Ban Treaty (CTBT, 1996), for four research areas: source physics (understanding signal generation), signal propagation (accounting for changes through physical media), sensors (recording the signals), and signal analysis (processing the signal). Over 40 trends are addressed, such as moving from 1D to 3D earth models, from pick-based seismic event processing to full waveform processing, and from separate treatment of mechanical waves in different media to combined analyses. Highlighted in the documentmore » for each trend are the value and benefit to the monitoring mission, key papers that advanced the science, and promising research and development for the future.« less

A generalized framework for nucleosynthesis calculations

NASA Astrophysics Data System (ADS)

Sprouse, Trevor; Mumpower, Matthew; Aprahamian, Ani

2014-09-01

Simulating astrophysical events is a difficult process, requiring a detailed pairing of knowledge from both astrophysics and nuclear physics. Astrophysics guides the thermodynamic evolution of an astrophysical event. We present a nucleosynthesis framework written in Fortran that combines as inputs a thermodynamic evolution and nuclear data to time evolve the abundances of nuclear species. Through our coding practices, we have emphasized the applicability of our framework to any astrophysical event, including those involving nuclear fission. Because these calculations are often very complicated, our framework dynamically optimizes itself based on the conditions at each time step in order to greatly minimize total computation time. To highlight the power of this new approach, we demonstrate the use of our framework to simulate both Big Bang nucleosynthesis and r-process nucleosynthesis with speeds competitive with current solutions dedicated to either process alone.

Bubblers Speed Nuclear Waste Processing at SRS

ScienceCinema

None

2018-05-23

At the Department of Energy's Savannah River Site, American Recovery and Reinvestment Act funding has supported installation of bubbler technology and related enhancements in the Defense Waste Processing Facility (DWPF). The improvements will accelerate the processing of radioactive waste into a safe, stable form for storage and permit expedited closure of underground waste tanks holding 37 million gallons of liquid nuclear waste.

Conceptual Design of Low-Temperature Hydrogen Production and High-Efficiency Nuclear Reactor Technology

NASA Astrophysics Data System (ADS)

Fukushima, Kimichika; Ogawa, Takashi

Hydrogen, a potential alternative energy source, is produced commercially by methane (or LPG) steam reforming, a process that requires high temperatures, which are produced by burning fossil fuels. However, as this process generates large amounts of CO2, replacement of the combustion heat source with a nuclear heat source for 773-1173K processes has been proposed in order to eliminate these CO2 emissions. In this paper, a novel method of nuclear hydrogen production by reforming dimethyl ether (DME) with steam at about 573K is proposed. From a thermodynamic equilibrium analysis of DME steam reforming, the authors identified conditions that provide high hydrogen production fraction at low pressure and temperatures of about 523-573K. By setting this low-temperature hydrogen production process upstream from a turbine and nuclear reactor at about 573K, the total energy utilization efficiency according to equilibrium mass and heat balance analysis is about 50%, and it is 75%for a fast breeder reactor (FBR), where turbine is upstream of the reformer.

Processing and fabrication of mixed uranium/refractory metal carbide fuels with liquid-phase sintering

NASA Astrophysics Data System (ADS)

Knight, Travis W.; Anghaie, Samim

2002-11-01

Optimization of powder processing techniques were sought for the fabrication of single-phase, solid-solution mixed uranium/refractory metal carbide nuclear fuels - namely (U, Zr, Nb)C. These advanced, ultra-high temperature nuclear fuels have great potential for improved performance over graphite matrix, dispersed fuels tested in the Rover/NERVA program of the 1960s and early 1970s. Hypostoichiometric fuel samples with carbon-to-metal ratios of 0.98, uranium metal mole fractions of 5% and 10%, and porosities less than 5% were fabricated. These qualities should provide for the longest life and highest performance capability for these fuels. Study and optimization of processing methods were necessary to provide the quality assurance of samples for meaningful testing and assessment of performance for nuclear thermal propulsion applications. The processing parameters and benefits of enhanced sintering by uranium carbide liquid-phase sintering were established for the rapid and effective consolidation and formation of a solid-solution mixed carbide nuclear fuel.

Examining Quality Management Audits in Nuclear Medicine Practice as a lifelong learning process: opportunities and challenges to the nuclear medicine professional and beyond.

PubMed

Pascual, Thomas N B

2016-08-01

This essay will explore the critical issues and challenges surrounding lifelong learning for professionals, initially exploring within the profession and organizational context of nuclear medicine practice. It will critically examine how the peer-review process called Quality Management Audits in Nuclear Medicine Practice (QUANUM) of the International Atomic Energy Agency (IAEA) can be considered a lifelong learning opportunity to instill a culture of quality to improve patient care and elevate the status of the nuclear medicine profession and practice within the demands of social changes, policy, and globalization. This will be explored initially by providing contextual background to the identity of the IAEA as an organization responsible for nuclear medicine professionals, followed by the benefits that QUANUM can offer. Further key debates surrounding lifelong learning, such as compulsification of lifelong learning and impact on professional change, will then be weaved through the discussion using theoretical grounding through a qualitative review of the literature. Keeping in mind that there is very limited literature focusing on the implications of QUANUM as a lifelong learning process for nuclear medicine professionals, this essay uses select narratives and observations of QUANUM as a lifelong learning process from an auditor's perspective and will further provide a comparative perspective of QUANUM on the basis of other lifelong learning opportunities such as continuing professional development activities and observe parallelisms on its benefits and challenges that it will offer to other professionals in other medical speciality fields and in the teaching profession.

Nuclear Fuel Cycle Introductory Concepts

DOE Office of Scientific and Technical Information (OSTI.GOV)

Karpius, Peter Joseph

2017-02-02

The nuclear fuel cycle is a complex entity, with many stages and possibilities, encompassing natural resources, energy, science, commerce, and security, involving a host of nations around the world. This overview describes the process for generating nuclear power using fissionable nuclei.

Radiochemical Processing Laboratory (RPL) at PNNL

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peurrung, Tony; Clark, Sue; Bryan, Sam

2017-03-23

Nuclear research is one of the core components of PNNL's mission. The centerpiece of PNNL's nuclear research is the Radiochemical Processing Laboratory (RPL), a Category 2 nuclear facility with state-of-the-art instrumentation, scientific expertise, and specialized capabilities that enable research with significant quantities of fissionable materials and other radionuclides—from tritium to plutonium. High impact radiological research has been conducted in the RPL since the 1950's, when nuclear weapons and energy production at Hanford were at the forefront of national defense. Since then, significant investments have been made in the RPL to maintain it as a premier nuclear science research facility supportingmore » multiple programs. Most recently, PNNL is developing a world-class analytical electron microscopy facility dedicated to the characterization of radiological materials.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yoshikatsu, Yuki; Ishida, Yo-ichi; Sudo, Haruka

Nuclear VCP-like 2 (NVL2) is a member of the chaperone-like AAA-ATPase family and is involved in the biosynthesis of 60S ribosomal subunits in mammalian cells. We previously showed the interaction of NVL2 with a DExD/H-box RNA helicase MTR4/DOB1, which is a known cofactor for an exoribonuclease complex, the exosome. This finding implicated NVL2 in RNA metabolic processes during ribosome biogenesis. In the present study, we found that a series of mutations within the ATPase domain of NVL2 causes a defect in pre-rRNA processing into mature 28S and 5.8S rRNAs. Co-immunoprecipitation analysis showed that NVL2 was associated with the nuclear exosomemore » complex, which includes RRP6 as a nucleus-specific catalytic subunit. This interaction was prevented by depleting either MTR4 or RRP6, indicating their essential role in mediating this interaction with NVL2. Additionally, knockdown of MPP6, another cofactor for the nuclear exosome, also prevented the interaction by causing MTR4 to dissociate from the nuclear exosome. These results suggest that NVL2 is involved in pre-rRNA processing by associating with the nuclear exosome complex and that MPP6 is required for maintaining the integrity of this rRNA processing complex. - Highlights: • ATPase-deficient mutants of NVL2 have decreased pre-rRNA processing. • NVL2 associates with the nuclear exosome through interactions with MTR4 and RRP6. • MPP6 stabilizes MTR4-RRP6 interaction and allows NVL2 to interact with the complex.« less

Geoscientific Site Evaluation Approach for Canada's Deep Geological Repository for Used Nuclear Fuel

NASA Astrophysics Data System (ADS)

Sanchez-Rico Castejon, M.; Hirschorn, S.; Ben Belfadhel, M.

2015-12-01

The Nuclear Waste Management Organization (NWMO) is responsible for implementing Adaptive Phased Management, the approach selected by the Government of Canada for long-term management of used nuclear fuel generated by Canadian nuclear reactors. The ultimate objective of APM is the centralized containment and isolation of Canada's used nuclear fuel in a Deep Geological Repository in a suitable crystalline or sedimentary rock formation. In May 2010, the NWMO published and initiated a nine-step site selection process to find an informed and willing community to host a deep geological repository for Canada's used nuclear fuel. The site selection process is designed to address a broad range of technical and social, economic and cultural factors. The site evaluation process includes three main technical evaluation steps: Initial Screenings; Preliminary Assessments; and Detailed Site Characterizations, to assess the suitability of candidate areas in a stepwise manner over a period of many years. By the end of 2012, twenty two communities had expressed interest in learning more about the project. As of July 2015, nine communities remain in the site selection process. To date (July 2015), NWMO has completed Initial Screenings for the 22 communities that expressed interest, and has completed the first phase of Preliminary Assessments (desktop) for 20 of the communities. Phase 2 of the Preliminary Assessments has been initiated in a number of communities, with field activities such as high-resolution airborne geophysical surveys and geological mapping. This paper describes the approach, methods and criteria being used to assess the geoscientific suitability of communities currently involved in the site selection process.

Approximating the r-Process on Earth with Thermonuclear Explosions. Lessons Learned and Unanswered Questions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Becker, Stephen Allan

2016-01-28

During the astrophysical r-process, multiple neutron captures occur so rapidly on target nuclei that their daughter nuclei generally do not have time to undergo radioactive decay before another neutron is captured. The r-process can be approximately simulated on Earth in certain types of thermonuclear explosions through an analogous process of rapid neutron captures known as the "prompt capture" process. Between 1952 and 1969, 23 nuclear tests were fielded by the US which were involved (at least partially) with the "prompt capture" process. Of these tests, 15 were at least partially successful. Some of these tests were conducted under the Plowsharemore » Peaceful Nuclear Explosion Program as scientific research experiments. It is now known that the USSR conducted similar nuclear tests during 1966 to 1979. The elements einsteinium and fermium were first discovered by this process. The most successful tests achieved 19 successive neutron captures on the initial target nuclei. A review of the US program, target nuclei used, heavy element yields, scientific achievements of the program, and how some of the results have been used by the astrophysical community is given. Finally, some unanswered questions concerning very neutron-rich nuclei that could potentially have been answered with additional nuclear experiments is presented.« less

Nuclear Security Objectives of an NMAC System

DOE Office of Scientific and Technical Information (OSTI.GOV)

West, Rebecca Lynn

After completing this module, you should be able to: Describe the role of Nuclear Material Accounting and Control (NMAC) in comprehensive nuclear security at a facility; Describe purpose of NMAC; Identify differences between the use of NMAC for IAEA safeguards and for facility nuclear security; List NMAC elements and measures; and Describe process for resolution of irregularities

Photonuclear reactions in astrophysical p-process: Theoretical calculations and experiment simulation based on ELI-NP

NASA Astrophysics Data System (ADS)

Xu, Yi; Luo, Wen; Balabanski, Dimiter; Goriely, Stephane; Matei, Catalin; Tesileanu, Ovidiu

2017-09-01

The astrophysical p-process is an important way of nucleosynthesis to produce the stable and proton-rich nuclei beyond Fe which can not be reached by the s- and r-processes. In the present study, the astrophysical reaction rates of (γ,n), (γ,p), and (γ,α) reactions are computed within the modern reaction code TALYS for about 3000 stable and proton-rich nuclei with 12 < Z < 110. The nuclear structure ingredients involved in the calculation are determined from experimental data whenever available and, if not, from global microscopic nuclear models. In particular, both of the Wood-Saxon potential and the double folding potential with density dependent M3Y (DDM3Y) effective interaction are used for the calculations. It is found that the photonuclear reaction rates are very sensitive to the nuclear potential, and the better determination of nuclear potential would be important to reduce the uncertainties of reaction rates. Meanwhile, the Extreme Light Infrastructure-Nuclear Physics (ELI-NP) facility is being developed, which will provide the great opportunity to experimentally study the photonuclear reactions in p-process. Simulations of the experimental setup for the measurements of the photonuclear reactions 96Ru(γ,p) and 96Ru(γ,α) are performed. It is shown that the experiments of photonuclear reactions in p-process based on ELI-NP are quite promising.

Status of nuclear PDFs after the first LHC p-Pb run

NASA Astrophysics Data System (ADS)

Paukkunen, Hannu

2017-11-01

In this talk, I overview the recent progress on the global analysis of nuclear parton distribution functions (nuclear PDFs). After first introducing the contemporary fits, the analysis procedures are quickly recalled and the ambiguities in the use of experimental data outlined. Various nuclear-PDF parametrizations are compared and the main differences explained. The effects of nuclear PDFs in the LHC p-Pb hard-process observables are discussed and some future prospects sketched.

A Nuclear Waste Management Cost Model for Policy Analysis

NASA Astrophysics Data System (ADS)

Barron, R. W.; Hill, M. C.

2017-12-01

Although integrated assessments of climate change policy have frequently identified nuclear energy as a promising alternative to fossil fuels, these studies have often treated nuclear waste disposal very simply. Simple assumptions about nuclear waste are problematic because they may not be adequate to capture relevant costs and uncertainties, which could result in suboptimal policy choices. Modeling nuclear waste management costs is a cross-disciplinary, multi-scale problem that involves economic, geologic and environmental processes that operate at vastly different temporal scales. Similarly, the climate-related costs and benefits of nuclear energy are dependent on environmental sensitivity to CO2 emissions and radiation, nuclear energy's ability to offset carbon emissions, and the risk of nuclear accidents, factors which are all deeply uncertain. Alternative value systems further complicate the problem by suggesting different approaches to valuing intergenerational impacts. Effective policy assessment of nuclear energy requires an integrated approach to modeling nuclear waste management that (1) bridges disciplinary and temporal gaps, (2) supports an iterative, adaptive process that responds to evolving understandings of uncertainties, and (3) supports a broad range of value systems. This work develops the Nuclear Waste Management Cost Model (NWMCM). NWMCM provides a flexible framework for evaluating the cost of nuclear waste management across a range of technology pathways and value systems. We illustrate how NWMCM can support policy analysis by estimating how different nuclear waste disposal scenarios developed using the NWMCM framework affect the results of a recent integrated assessment study of alternative energy futures and their effects on the cost of achieving carbon abatement targets. Results suggest that the optimism reflected in previous works is fragile: Plausible nuclear waste management costs and discount rates appropriate for intergenerational cost-benefit analysis produce many scenarios where nuclear energy is economically unattractive.

10 CFR 1707.205 - Processing demands or requests.

Code of Federal Regulations, 2011 CFR

2011-01-01

... 10 Energy 4 2011-01-01 2011-01-01 false Processing demands or requests. 1707.205 Section 1707.205 Energy DEFENSE NUCLEAR FACILITIES SAFETY BOARD TESTIMONY BY DNFSB EMPLOYEES AND PRODUCTION OF OFFICIAL... and/or produce official records and information. (b) The Defense Nuclear Facilities Safety Board will...

10 CFR 1707.205 - Processing demands or requests.

Code of Federal Regulations, 2013 CFR

2013-01-01

... 10 Energy 4 2013-01-01 2013-01-01 false Processing demands or requests. 1707.205 Section 1707.205 Energy DEFENSE NUCLEAR FACILITIES SAFETY BOARD TESTIMONY BY DNFSB EMPLOYEES AND PRODUCTION OF OFFICIAL... and/or produce official records and information. (b) The Defense Nuclear Facilities Safety Board will...

10 CFR 1707.205 - Processing demands or requests.

Code of Federal Regulations, 2010 CFR

2010-01-01

... 10 Energy 4 2010-01-01 2010-01-01 false Processing demands or requests. 1707.205 Section 1707.205 Energy DEFENSE NUCLEAR FACILITIES SAFETY BOARD TESTIMONY BY DNFSB EMPLOYEES AND PRODUCTION OF OFFICIAL... and/or produce official records and information. (b) The Defense Nuclear Facilities Safety Board will...

10 CFR 1707.205 - Processing demands or requests.

Code of Federal Regulations, 2014 CFR

2014-01-01

... 10 Energy 4 2014-01-01 2014-01-01 false Processing demands or requests. 1707.205 Section 1707.205 Energy DEFENSE NUCLEAR FACILITIES SAFETY BOARD TESTIMONY BY DNFSB EMPLOYEES AND PRODUCTION OF OFFICIAL... and/or produce official records and information. (b) The Defense Nuclear Facilities Safety Board will...

10 CFR 1707.205 - Processing demands or requests.

Code of Federal Regulations, 2012 CFR

2012-01-01

... 10 Energy 4 2012-01-01 2012-01-01 false Processing demands or requests. 1707.205 Section 1707.205 Energy DEFENSE NUCLEAR FACILITIES SAFETY BOARD TESTIMONY BY DNFSB EMPLOYEES AND PRODUCTION OF OFFICIAL... and/or produce official records and information. (b) The Defense Nuclear Facilities Safety Board will...

When Fear Ruled: Rethinking the Cuban Missile Crisis.

ERIC Educational Resources Information Center

Paterson, Thomas G.

1995-01-01

Provides an insightful look at the administrative and negotiative processes that accompanied the 1962 Cuban missile crisis. Although John F. Kennedy and Nikita Khrushchev both worked to avoid nuclear war, the stress and exhaustion of the negotiating process created serious blunders. Eventually both sides backed away from nuclear annihilation. (MJP)

Calculation of the process of vacuum drying of a metal-concrete container with spent nuclear fuel

NASA Astrophysics Data System (ADS)

Karyakin, Yu. E.; Lavrent'ev, S. A.; Pavlyukevich, N. V.; Pletnev, A. A.; Fedorovich, E. D.

2012-01-01

An algorithm and results of calculation of the process of vacuum drying of a metal-concrete container intended for long-term "dry" storage of spent nuclear fuel are presented. A calculated substantiation of the initial amount of moisture in the container is given.

Startup of Pumping Units in Process Water Supplies with Cooling Towers at Thermal and Nuclear Power Plants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berlin, V. V., E-mail: vberlin@rinet.ru; Murav’ev, O. A., E-mail: muraviov1954@mail.ru; Golubev, A. V., E-mail: electronik@inbox.ru

Aspects of the startup of pumping units in the cooling and process water supply systems for thermal and nuclear power plants with cooling towers, the startup stages, and the limits imposed on the extreme parameters during transients are discussed.

Features of cues and processes during chloroplast-mediated retrograde signaling in the alga Chlamydomonas

USDA-ARS?s Scientific Manuscript database

Retrograde signalling is a selective process defined by cues generated in chloroplast/mitochondria which traverse membranes and end up regulating nuclear gene expression and protein synthesis. The coding and encoding of organellar message(s) that alter nuclear gene expression and/or cellular metabo...

The Feed Materials Program of the Manhattan Project: A Foundational Component of the Nuclear Weapons Complex

NASA Astrophysics Data System (ADS)

Reed, B. Cameron

2014-12-01

The feed materials program of the Manhattan Project was responsible for procuring uranium-bearing ores and materials and processing them into forms suitable for use as source materials for the Project's uranium-enrichment factories and plutonium-producing reactors. This aspect of the Manhattan Project has tended to be overlooked in comparison with the Project's more dramatic accomplishments, but was absolutely vital to the success of those endeavors: without appropriate raw materials and the means to process them, nuclear weapons and much of the subsequent cold war would never have come to pass. Drawing from information available in Manhattan Engineer District Documents, this paper examines the sources and processing of uranium-bearing materials used in making the first nuclear weapons and how the feed materials program became a central foundational component of the postwar nuclear weapons complex.

Precision and accuracy of nuclear asphalt content gauges in determining asphalt content in asphaltic concrete pavement.

DOT National Transportation Integrated Search

1988-06-17

Use of nuclear asphalt content gauges for determining asphalt content of asphaltic concrete pavement are gaining acceptance as an alternative method to the vacuum extraction process. The reasons nuclear asphalt content gauges are considered promising...

Nuclear ARP2/3 drives DNA break clustering for homology-directed repair.

PubMed

Schrank, Benjamin R; Aparicio, Tomas; Li, Yinyin; Chang, Wakam; Chait, Brian T; Gundersen, Gregg G; Gottesman, Max E; Gautier, Jean

2018-06-20

DNA double-strand breaks repaired by non-homologous end joining display limited DNA end-processing and chromosomal mobility. By contrast, double-strand breaks undergoing homology-directed repair exhibit extensive processing and enhanced motion. The molecular basis of this movement is unknown. Here, using Xenopus laevis cell-free extracts and mammalian cells, we establish that nuclear actin, WASP, and the actin-nucleating ARP2/3 complex are recruited to damaged chromatin undergoing homology-directed repair. We demonstrate that nuclear actin polymerization is required for the migration of a subset of double-strand breaks into discrete sub-nuclear clusters. Actin-driven movements specifically affect double-strand breaks repaired by homology-directed repair in G2 cell cycle phase; inhibition of actin nucleation impairs DNA end-processing and homology-directed repair. By contrast, ARP2/3 is not enriched at double-strand breaks repaired by non-homologous end joining and does not regulate non-homologous end joining. Our findings establish that nuclear actin-based mobility shapes chromatin organization by generating repair domains that are essential for homology-directed repair in eukaryotic cells.

Encoded physics knowledge in checking codes for nuclear cross section libraries at Los Alamos

NASA Astrophysics Data System (ADS)

Parsons, D. Kent

2017-09-01

Checking procedures for processed nuclear data at Los Alamos are described. Both continuous energy and multi-group nuclear data are verified by locally developed checking codes which use basic physics knowledge and common-sense rules. A list of nuclear data problems which have been identified with help of these checking codes is also given.

Understanding the Value of a Computer Emergency Response Capability for Nuclear Security

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gasper, Peter Donald; Rodriguez, Julio Gallardo

The international nuclear community has a great understanding of the physical security needs relating to the prevention, detection, and response of malicious acts associated with nuclear facilities and radioactive material. International Atomic Energy Agency (IAEA) Nuclear Security Recommendations (INFCIRC_225_Rev 5) outlines specific guidelines and recommendations for implementing and maintaining an organization’s nuclear security posture. An important element for inclusion into supporting revision 5 is the establishment of a “Cyber Emergency Response Team (CERT)” focused on the international communities cybersecurity needs to maintain a comprehensive nuclear security posture. Cybersecurity and the importance of nuclear cybersecurity require that there be a specificmore » focus on developing an International Nuclear CERT (NS-CERT). States establishing contingency plans should have an understanding of the cyber threat landscape and the potential impacts to systems in place to protect and mitigate malicious activities. This paper will outline the necessary components, discuss the relationships needed within the international community, and outline a process by which the NS-CERT identifies, collects, processes, and reports critical information in order to establish situational awareness (SA) and support decision-making« less

Regulated transport into the nucleus of herpesviridae DNA replication core proteins.

PubMed

Gualtiero, Alvisi; Jans, David A; Camozzi, Daria; Avanzi, Simone; Loregian, Arianna; Ripalti, Alessandro; Palù, Giorgio

2013-09-16

The Herpesvirdae family comprises several major human pathogens belonging to three distinct subfamilies. Their double stranded DNA genome is replicated in the nuclei of infected cells by a number of host and viral products. Among the latter the viral replication complex, whose activity is strictly required for viral replication, is composed of six different polypeptides, including a two-subunit DNA polymerase holoenzyme, a trimeric primase/helicase complex and a single stranded DNA binding protein. The study of herpesviral DNA replication machinery is extremely important, both because it provides an excellent model to understand processes related to eukaryotic DNA replication and it has important implications for the development of highly needed antiviral agents. Even though all known herpesviruses utilize very similar mechanisms for amplification of their genomes, the nuclear import of the replication complex components appears to be a heterogeneous and highly regulated process to ensure the correct spatiotemporal localization of each protein. The nuclear transport process of these enzymes is controlled by three mechanisms, typifying the main processes through which protein nuclear import is generally regulated in eukaryotic cells. These include cargo post-translational modification-based recognition by the intracellular transporters, piggy-back events allowing coordinated nuclear import of multimeric holoenzymes, and chaperone-assisted nuclear import of specific subunits. In this review we summarize these mechanisms and discuss potential implications for the development of antiviral compounds aimed at inhibiting the Herpesvirus life cycle by targeting nuclear import of the Herpesvirus DNA replicating enzymes.

Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux

DOEpatents

Bowman, C.D.

1992-11-03

Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux. High thermal neutron fluxes generated from the action of a high power proton accelerator on a spallation target allows the efficient burn-up of higher actinide nuclear waste by a two-step process. Additionally, rapid burn-up of fission product waste for nuclides having small thermal neutron cross sections, and the practicality of small material inventories while achieving significant throughput derive from employment of such high fluxes. Several nuclear technology problems are addressed including 1. nuclear energy production without a waste stream requiring storage on a geological timescale, 2. the burn-up of defense and commercial nuclear waste, and 3. the production of defense nuclear material. The apparatus includes an accelerator, a target for neutron production surrounded by a blanket region for transmutation, a turbine for electric power production, and a chemical processing facility. In all applications, the accelerator power may be generated internally from fission and the waste produced thereby is transmuted internally so that waste management might not be required beyond the human lifespan.

Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux

DOEpatents

Bowman, Charles D.

1992-01-01

Apparatus for nuclear transmutation and power production using an intense accelerator-generated thermal neutron flux. High thermal neutron fluxes generated from the action of a high power proton accelerator on a spallation target allows the efficient burn-up of higher actinide nuclear waste by a two-step process. Additionally, rapid burn-up of fission product waste for nuclides having small thermal neutron cross sections, and the practicality of small material inventories while achieving significant throughput derive from employment of such high fluxes. Several nuclear technology problems are addressed including 1. nuclear energy production without a waste stream requiring storage on a geological timescale, 2. the burn-up of defense and commercial nuclear waste, and 3. the production of defense nuclear material. The apparatus includes an accelerator, a target for neutron production surrounded by a blanket region for transmutation, a turbine for electric power production, and a chemical processing facility. In all applications, the accelerator power may be generated internally from fission and the waste produced thereby is transmuted internally so that waste management might not be required beyond the human lifespan.

Extraction study on uranyl nitrate for energy applications

NASA Astrophysics Data System (ADS)

Giri, R.; Nath, G.

2017-07-01

Due to the ever-growing demand of energy nuclear reactor materials and the nuclear energy are now considered to be the most critical materials and source of energy for future era. Deposition of nuclear wastes in different industry, nuclear power sector are very much toxic in open environment which are hazardous to living being. There are different methods for extraction and reprocessing of these materials which are cost effective and tedious process. Ultrasonic assisted solvent extraction process is a most efficient and economical way for extraction of such type materials. The presence of third phase in mixing of extractants-diluent pair with aqueous phase imposes the problems in extraction of nuclear reactor materials. The appropriate solvent mixture in proper concentration is an important step in the solvent extraction process. Study of thermo-physical properties helps in selecting an optimum blend for extraction process. In the present work, the extraction of uranium with the binary mixture of Methyl Ethyl Ketone (MEK) and Kerosene was investigated and discussed with the variation of ultrasonic frequency for different temperatures. The result shows that the low frequency and low temperature is suitable environment for extraction. The extraction of uranium by this method is found to be a better result for extraction study in laboratory scale as well as industrial sector.

Confocal Analysis of Nuclear Lamina Behavior during Male Meiosis and Spermatogenesis in Drosophila melanogaster.

PubMed

Fabbretti, Fabiana; Iannetti, Ilaria; Guglielmi, Loredana; Perconti, Susanna; Evangelistella, Chiara; Proietti De Santis, Luca; Bongiorni, Silvia; Prantera, Giorgio

2016-01-01

Lamin family proteins are structural components of a filamentous framework, the nuclear lamina (NL), underlying the inner membrane of nuclear envelope. The NL not only plays a role in nucleus mechanical support and nuclear shaping, but is also involved in many cellular processes including DNA replication, gene expression and chromatin positioning. Spermatogenesis is a very complex differentiation process in which each stage is characterized by nuclear architecture dramatic changes, from the early mitotic stage to the sperm differentiation final stage. Nevertheless, very few data are present in the literature on the NL behavior during this process. Here we show the first and complete description of NL behavior during meiosis and spermatogenesis in Drosophila melanogaster. By confocal imaging, we characterized the NL modifications from mitotic stages, through meiotic divisions to sperm differentiation with an anti-laminDm0 antibody against the major component of the Drosophila NL. We observed that continuous changes in the NL structure occurred in parallel with chromatin reorganization throughout the whole process and that meiotic divisions occurred in a closed context. Finally, we analyzed NL in solofuso meiotic mutant, where chromatin segregation is severely affected, and found the strict correlation between the presence of chromatin and that of NL.

Confocal Analysis of Nuclear Lamina Behavior during Male Meiosis and Spermatogenesis in Drosophila melanogaster

PubMed Central

Fabbretti, Fabiana; Iannetti, Ilaria; Guglielmi, Loredana; Perconti, Susanna; Evangelistella, Chiara; Proietti De Santis, Luca; Bongiorni, Silvia; Prantera, Giorgio

2016-01-01

Lamin family proteins are structural components of a filamentous framework, the nuclear lamina (NL), underlying the inner membrane of nuclear envelope. The NL not only plays a role in nucleus mechanical support and nuclear shaping, but is also involved in many cellular processes including DNA replication, gene expression and chromatin positioning. Spermatogenesis is a very complex differentiation process in which each stage is characterized by nuclear architecture dramatic changes, from the early mitotic stage to the sperm differentiation final stage. Nevertheless, very few data are present in the literature on the NL behavior during this process. Here we show the first and complete description of NL behavior during meiosis and spermatogenesis in Drosophila melanogaster. By confocal imaging, we characterized the NL modifications from mitotic stages, through meiotic divisions to sperm differentiation with an anti-laminDm0 antibody against the major component of the Drosophila NL. We observed that continuous changes in the NL structure occurred in parallel with chromatin reorganization throughout the whole process and that meiotic divisions occurred in a closed context. Finally, we analyzed NL in solofuso meiotic mutant, where chromatin segregation is severely affected, and found the strict correlation between the presence of chromatin and that of NL. PMID:26963718

SUN1 Regulates HIV-1 Nuclear Import in a Manner Dependent on the Interaction between the Viral Capsid and Cellular Cyclophilin A.

PubMed

Luo, Xinlong; Yang, Wei; Gao, Guangxia

2018-07-01

Human immunodeficiency virus type 1 (HIV-1) can infect nondividing cells via passing through the nuclear pore complex. The nuclear membrane-imbedded protein SUN2 was recently reported to be involved in the nuclear import of HIV-1. Whether SUN1, which shares many functional similarities with SUN2, is involved in this process remained to be explored. Here we report that overexpression of SUN1 specifically inhibited infection by HIV-1 but not that by simian immunodeficiency virus (SIV) or murine leukemia virus (MLV). Overexpression of SUN1 did not affect reverse transcription but led to reduced accumulation of the 2-long-terminal-repeat (2-LTR) circular DNA and integrated viral DNA, suggesting a block in the process of nuclear import. HIV-1 CA was mapped as a determinant for viral sensitivity to SUN1. Treatment of SUN1-expressing cells with cyclosporine (CsA) significantly reduced the sensitivity of the virus to SUN1, and an HIV-1 mutant containing CA-G89A, which does not interact with cyclophilin A (CypA), was resistant to SUN1 overexpression. Downregulation of endogenous SUN1 inhibited the nuclear entry of the wild-type virus but not that of the G89A mutant. These results indicate that SUN1 participates in the HIV-1 nuclear entry process in a manner dependent on the interaction of CA with CypA. IMPORTANCE HIV-1 infects both dividing and nondividing cells. The viral preintegration complex (PIC) can enter the nucleus through the nuclear pore complex. It has been well known that the viral protein CA plays an important role in determining the pathways by which the PIC enters the nucleus. In addition, the interaction between CA and the cellular protein CypA has been reported to be important in the selection of nuclear entry pathways, though the underlying mechanisms are not very clear. Here we show that both SUN1 overexpression and downregulation inhibited HIV-1 nuclear entry. CA played an important role in determining the sensitivity of the virus to SUN1: the regulatory activity of SUN1 toward HIV-1 relied on the interaction between CA and CypA. These results help to explain how SUN1 is involved in the HIV-1 nuclear entry process. Copyright © 2018 American Society for Microbiology.

Managing the Nuclear Fuel Cycle: Policy Implications of Expanding Global Access to Nuclear Power

DTIC Science & Technology

2008-01-20

critical aspect of the nuclear fuel cycle for the United States, where longstanding nonproliferation policy discouraged commercial nuclear fuel...have U.S. government officials. However, the case of Iran raises perhaps the most critical question in this decade for strengthening the nuclear...slight difference in atomic mass between 235U and 238U. The typical enrichment process requires about 10 lbs of uranium U3O8 to produce 1 lb of low

The Future Nuclear Arms Control Agenda and Its Potential Implications for the Air Force

DTIC Science & Technology

2015-08-01

triad of delivery systems will need to be replaced. Nuclear warhead life-cycle extension also will need to continue, assuming it remains too difficult...U.S. and Russian strategic nuclear forces. Thus, formal U.S.-Russian arms control negotiations for strategic nuclear systems will almost certainly...reductions in numbers of deployed systems to a more far-reaching agreement that would begin a process of verified elimination of nuclear warheads. The

40 CFR 192.32 - Standards.

Code of Federal Regulations, 2011 CFR

2011-07-01

... § 192.32 Standards. (a) Standards for application during processing operations and prior to the end of... nonoperational and subject to a license by the Nuclear Regulatory Commission or an Agreement State shall limit... the Nuclear Regulatory Commission or Agreement State into individual site licenses. (ii) The Nuclear...

40 CFR 192.32 - Standards.

Code of Federal Regulations, 2010 CFR

2010-07-01

... § 192.32 Standards. (a) Standards for application during processing operations and prior to the end of... nonoperational and subject to a license by the Nuclear Regulatory Commission or an Agreement State shall limit... the Nuclear Regulatory Commission or Agreement State into individual site licenses. (ii) The Nuclear...

A Discrepancy-Based Methodology for Nuclear Training Program Evaluation.

ERIC Educational Resources Information Center

Cantor, Jeffrey A.

1991-01-01

A three-phase comprehensive process for commercial nuclear power training program evaluation is presented. The discrepancy-based methodology was developed after the Three Mile Island nuclear reactor accident. It facilitates analysis of program components to identify discrepancies among program specifications, actual outcomes, and industry…

10 CFR 110.1 - Purpose and scope.

Code of Federal Regulations, 2010 CFR

2010-01-01

... zirconium, rotor and bellows equipment, maraging steel, nuclear reactor related equipment, including process... 10 Energy 2 2010-01-01 2010-01-01 false Purpose and scope. 110.1 Section 110.1 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) EXPORT AND IMPORT OF NUCLEAR EQUIPMENT AND MATERIAL General Provisions...

Automatic sample changer control software for automation of neutron activation analysis process in Malaysian Nuclear Agency

NASA Astrophysics Data System (ADS)

Yussup, N.; Ibrahim, M. M.; Rahman, N. A. A.; Mokhtar, M.; Salim, N. A. A.; Soh@Shaari, S. C.; Azman, A.; Lombigit, L.; Azman, A.; Omar, S. A.

2018-01-01

Most of the procedures in neutron activation analysis (NAA) process that has been established in Malaysian Nuclear Agency (Nuclear Malaysia) since 1980s were performed manually. These manual procedures carried out by the NAA laboratory personnel are time consuming and inefficient especially for sample counting and measurement process. The sample needs to be changed and the measurement software needs to be setup for every one hour counting time. Both of these procedures are performed manually for every sample. Hence, an automatic sample changer system (ASC) that consists of hardware and software is developed to automate sample counting process for up to 30 samples consecutively. This paper describes the ASC control software for NAA process which is designed and developed to control the ASC hardware and call GammaVision software for sample measurement. The software is developed by using National Instrument LabVIEW development package.

Enterprise SRS: leveraging ongoing operations to advance nuclear fuel cycles research and development programs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murray, A.M.; Marra, J.E.; Wilmarth, W.R.

2013-07-01

The Savannah River Site (SRS) is re-purposing its vast array of assets (including H Canyon - a nuclear chemical separation plant) to solve issues regarding advanced nuclear fuel cycle technologies, nuclear materials processing, packaging, storage and disposition. The vehicle for this transformation is Enterprise SRS which presents a new, radical view of SRS as a united endeavor for 'all things nuclear' as opposed to a group of distinct and separate entities with individual missions and organizations. Key among the Enterprise SRS strategic initiatives is the integration of research into SRS facilities but also in other facilities in conjunction with on-goingmore » missions to provide researchers from other national laboratories, academic institutions, and commercial entities the opportunity to demonstrate their technologies in a relevant environment and scale prior to deployment. To manage that integration of research demonstrations into site facilities, a center for applied nuclear materials processing and engineering research has been established in SRS.« less

Verification Study of Buoyancy-Driven Turbulent Nuclear Combustion

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2010-01-01

Buoyancy-driven turbulent nuclear combustion determines the rate of nuclear burning during the deflagration phase (i.e., the ordinary nuclear flame phase) of Type 1a supernovae, and hence the amount of nuclear energy released during this phase. It therefore determines the amount the white dwarf star expands prior to initiation of a detonation wave, and so the amount of radioactive nickel and thus the peak luminosity of the explosion. However, this key physical process is not fully understood. To better understand this process, the Flash Center has conducted an extensive series of large-scale 3D simulations of buoyancy-driven turbulent nuclear combustion for threemore » different physical situations. This movie shows the results for some of these simulations. Credits: Science: Ray Bair, Katherine Riley, Argonne National Laboratory; Anshu Dubey, Don Lamb, Dongwook Lee, University of Chicago; Robert Fisher, University of Massachusetts at Dartmouth and Dean Townsley, University of Alabama Visualization: Jonathan Gallagher, University of Chicago; Randy Hudson, John Norris and Michael E. Papka, Argonne National Laboratory/University of Chicago« less

Retinoic acid induces nuclear accumulation of Raf1 during differentiation of HL-60 cells

DOE Office of Scientific and Technical Information (OSTI.GOV)

Smith, James; Bunaciu, Rodica P.; Reiterer, Gudrun

All trans-retinoic acid (RA) is a standard therapeutic agent used in differentiation induction therapy treatment of acute promyelocytic leukemia (APL). RA and its metabolites use a diverse set of signal transduction pathways during the differentiation program. In addition to the direct transcriptional targets of the nuclear RAR and RXR receptors, signals derived from membrane receptors and the Raf-MEK-ERK pathway are required. Raf1 phosphorylation and the prolonged activation of Raf1 persisting during the entire differentiation process are required for RA-dependent differentiation of HL-60 cells. Here we identify a nuclear redistribution of Raf1 during the RA-induced differentiation of HL-60 cells. In addition,more » the nuclear accumulation of Raf1 correlates with an increase in Raf1 phosphorylated at serine 621. The serine 621 phosphorylated Raf1 is predominantly localized in the nucleus. The RA-dependent nuclear accumulation of Raf1 suggests a novel nuclear role for Raf1 during the differentiation process.« less

Quenching of dynamic nuclear polarization by spin-orbit coupling in GaAs quantum dots.

PubMed

Nichol, John M; Harvey, Shannon P; Shulman, Michael D; Pal, Arijeet; Umansky, Vladimir; Rashba, Emmanuel I; Halperin, Bertrand I; Yacoby, Amir

2015-07-17

The central-spin problem is a widely studied model of quantum decoherence. Dynamic nuclear polarization occurs in central-spin systems when electronic angular momentum is transferred to nuclear spins and is exploited in quantum information processing for coherent spin manipulation. However, the mechanisms limiting this process remain only partially understood. Here we show that spin-orbit coupling can quench dynamic nuclear polarization in a GaAs quantum dot, because spin conservation is violated in the electron-nuclear system, despite weak spin-orbit coupling in GaAs. Using Landau-Zener sweeps to measure static and dynamic properties of the electron spin-flip probability, we observe that the size of the spin-orbit and hyperfine interactions depends on the magnitude and direction of applied magnetic field. We find that dynamic nuclear polarization is quenched when the spin-orbit contribution exceeds the hyperfine, in agreement with a theoretical model. Our results shed light on the surprisingly strong effect of spin-orbit coupling in central-spin systems.

Computerized engineering logic for nuclear procurement and dedication processes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tulay, M.P.

1996-12-31

In an attempt to better meet the needs of operations and maintenance organizations, many nuclear utility procurement engineering groups have simplified their procedures, developed on-line tools for performing the specification of replacement items, and developed relational databases containing part-level information necessary to automate the procurement process. Although these improvements have helped to reduce the engineering necessary to properly specify and accept/dedicate items for nuclear safety-related applications, a number of utilities have recognized that additional long-term savings can be realized by integrating a computerized logic to assist technical procurement engineering personnel. The most commonly used logic follows the generic processes containedmore » in Electric Power Research Institute (EPRI) published guidelines. The processes are typically customized to some extent to accommodate each utility`s organizational structure, operating procedures, and strategic goals. This paper will discuss a typical logic that integrates the technical evaluation, acceptance, and receipt inspection and testing processes. The logic this paper will describe has been successfully integrated at a growing number of nuclear utilities and has produced numerous positive results. The application of the logic ensures that utility-wide standards or procedures, common among multi-site utilities, are followed.« less

Instrumentation and control upgrade plan for Browns Ferry nuclear plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Belew, M.R.; Langley, D.T.; Torok, R.C.

1992-01-01

A comprehensive upgrade of the instrumentation and control (I C) systems at a power plant represents a formidable project for any utility. For a nuclear plant, the extra safety and reliability requirements along with regulatory constraints add further complications and cost. The need for the upgrade must, therefore, be very compelling, and the process must be well planned from the start. This paper describes the steps taken to initiate the I C upgrade process for Tennessee Valley Authority's (TVA's) Browns Ferry 2 nuclear plant. It explains the impetus for the upgrade, the expected benefits, and the process by which systemmore » upgrades will be selected and implemented.« less

Human Cytomegalovirus UL50 and UL53 Recruit Viral Protein Kinase UL97, Not Protein Kinase C, for Disruption of Nuclear Lamina and Nuclear Egress in Infected Cells

PubMed Central

Sharma, Mayuri; Kamil, Jeremy P.; Coughlin, Margaret; Reim, Natalia I.

2014-01-01

Herpesvirus nucleocapsids traverse the nuclear envelope into the cytoplasm in a process called nuclear egress that includes disruption of the nuclear lamina. In several herpesviruses, a key player in nuclear egress is a complex of two proteins, whose homologs in human cytomegalovirus (HCMV) are UL50 and UL53. However, their roles in nuclear egress during HCMV infection have not been shown. Based largely on transfection studies, UL50 and UL53 have been proposed to facilitate disruption of the nuclear lamina by recruiting cellular protein kinase C (PKC), as occurs with certain other herpesviruses, and/or the viral protein kinase UL97 to phosphorylate lamins. To investigate these issues during HCMV infection, we generated viral mutants null for UL50 or UL53. Correlative light electron microscopic analysis of null mutant-infected cells showed the presence of intranuclear nucleocapsids and the absence of cytoplasmic nucleocapsids. Confocal immunofluorescence microscopy revealed that UL50 and UL53 are required for disruption of the nuclear lamina. A subpopulation of UL97 colocalized with the nuclear rim, and this was dependent on UL50 and, to a lesser extent, UL53. However, PKC was not recruited to the nuclear rim, and its localization was not affected by the absence of UL50 or UL53. Immunoprecipitation from cells infected with HCMV expressing tagged UL53 detected UL97 but not PKC. In summary, HCMV UL50 and UL53 are required for nuclear egress and disruption of nuclear lamina during HCMV infection, and they recruit UL97, not PKC, for these processes. Thus, despite the strong conservation of herpesvirus nuclear egress complexes, a key function can differ among them. PMID:24155370

Human cytomegalovirus UL50 and UL53 recruit viral protein kinase UL97, not protein kinase C, for disruption of nuclear lamina and nuclear egress in infected cells.

PubMed

Sharma, Mayuri; Kamil, Jeremy P; Coughlin, Margaret; Reim, Natalia I; Coen, Donald M

2014-01-01

Herpesvirus nucleocapsids traverse the nuclear envelope into the cytoplasm in a process called nuclear egress that includes disruption of the nuclear lamina. In several herpesviruses, a key player in nuclear egress is a complex of two proteins, whose homologs in human cytomegalovirus (HCMV) are UL50 and UL53. However, their roles in nuclear egress during HCMV infection have not been shown. Based largely on transfection studies, UL50 and UL53 have been proposed to facilitate disruption of the nuclear lamina by recruiting cellular protein kinase C (PKC), as occurs with certain other herpesviruses, and/or the viral protein kinase UL97 to phosphorylate lamins. To investigate these issues during HCMV infection, we generated viral mutants null for UL50 or UL53. Correlative light electron microscopic analysis of null mutant-infected cells showed the presence of intranuclear nucleocapsids and the absence of cytoplasmic nucleocapsids. Confocal immunofluorescence microscopy revealed that UL50 and UL53 are required for disruption of the nuclear lamina. A subpopulation of UL97 colocalized with the nuclear rim, and this was dependent on UL50 and, to a lesser extent, UL53. However, PKC was not recruited to the nuclear rim, and its localization was not affected by the absence of UL50 or UL53. Immunoprecipitation from cells infected with HCMV expressing tagged UL53 detected UL97 but not PKC. In summary, HCMV UL50 and UL53 are required for nuclear egress and disruption of nuclear lamina during HCMV infection, and they recruit UL97, not PKC, for these processes. Thus, despite the strong conservation of herpesvirus nuclear egress complexes, a key function can differ among them.

Nominations for the 2017 NNSA Pollution Prevention Awards

DOE Office of Scientific and Technical Information (OSTI.GOV)

Salzman, Sonja L.; Ballesteros Rodriguez, Sonia; Lopez, Lorraine Bonds

In the field of nuclear forensics, one of the biggest challenges is to dissolve postdetonation debris for analysis. Debris generated after a nuclear detonation is a glassy material that is difficult to dissolve with chemicals. Traditionally, concentrated nitric acid, hydrofluoric acid, or sulfuric acid are employed during the dissolution. These acids, due to their corrosive nature, are not suitable for in-field/on-site sample preparations. Uranium oxides are commonly present in nuclear fuel processing plants and nuclear research facilities. In uranium oxides, the level of uranium isotope enrichment is a sensitive indicator for nuclear nonproliferation and is monitored closely by the Internationalmore » Atomic Energy Agency (IAEA) to ensure there is no misuse of nuclear material or technology for nuclear weapons. During an IAEA on-site inspection at a facility, environmental surface swipe samples are collected and transported to the IAEA headquarters or network of analytical laboratories for further processing. Uranium oxide particles collected on the swipe medium are typically dissolved with inorganic acids and are then analyzed for uranium isotopic compositions. To improve the responsiveness of on-site inspections, in-field detection techniques have been recently explored. However, in-field analysis is bottlenecked by time-consuming and hazardous dissolution procedures, as corrosive inorganic acids must be used. Corrosive chemicals are difficult to use in the field due to personnel safety considerations, and the transportation of such chemicals is highly regulated. It was therefore necessary to develop fast uranium oxide dissolution methods using less hazardous chemicals in support of the rapid infield detection of anomalies in declared nuclear processes.« less

Ribonucleoprotein organization of eukaryotic RNA. XXXII. U2 small nuclear RNA precursors and their accurate 3' processing in vitro as ribonucleoprotein particles.

PubMed

Wieben, E D; Nenninger, J M; Pederson, T

1985-05-05

Biosynthetic precursors of U2 small nuclear RNA have been identified in cultured human cells by hybrid-selection of pulse-labeled RNA with cloned U2 DNA. These precursor molecules are one to approximately 16 nucleotides longer than mature U2 RNA and contain 2,2,7-trimethylguanosine "caps". The U2 RNA precursors are associated with proteins that react with a monoclonal antibody for antigens characteristic of small nuclear ribonucleoprotein particles. Like previously described precursors of U1 and U4 small nuclear RNAs, the pre-U2 RNAs are recovered in cytoplasmic fractions, although it is not known if this is their location in vivo. The precursors are processed to mature-size U2 RNA when cytoplasmic extracts are incubated in vitro at 37 degrees C. Mg2+ is required but ATP is not. The ribonucleoprotein structure of the pre-U2 RNA is maintained during the processing reaction in vitro, as are the 2,2,7-trimethylguanosine caps. The ribonucleoprotein organization is of major importance, as exogenous, protein-free U2 RNA precursors are degraded rapidly in the in vitro system. Two lines of evidence indicate that the conversion of U2 precursors to mature-size U2 RNA involves a 3' processing reaction. First, the reaction is unaffected by a large excess of mature U2 small nuclear RNP, whose 5' trimethylguanosine caps would be expected to compete for a 5' processing activity. Second, when pre-U2 RNA precursors are first stoichiometrically decorated with an antibody specific for 2,2,7-trimethylguanosine, the extent of subsequent processing in vitro is unaffected. These results provide the first demonstration of a eukaryotic RNA processing reaction in vitro occurring within a ribonucleoprotein particle.

Advancing Nucleosynthesis in Core-Collapse Supernovae Models Using 2D CHIMERA Simulations

NASA Astrophysics Data System (ADS)

Harris, J. A.; Hix, W. R.; Chertkow, M. A.; Bruenn, S. W.; Lentz, E. J.; Messer, O. B.; Mezzacappa, A.; Blondin, J. M.; Marronetti, P.; Yakunin, K.

2014-01-01

The deaths of massive stars as core-collapse supernovae (CCSN) serve as a crucial link in understanding galactic chemical evolution since the birth of the universe via the Big Bang. We investigate CCSN in polar axisymmetric simulations using the multidimensional radiation hydrodynamics code CHIMERA. Computational costs have traditionally constrained the evolution of the nuclear composition in CCSN models to, at best, a 14-species α-network. However, the limited capacity of the α-network to accurately evolve detailed composition, the neutronization and the nuclear energy generation rate has fettered the ability of prior CCSN simulations to accurately reproduce the chemical abundances and energy distributions as known from observations. These deficits can be partially ameliorated by "post-processing" with a more realistic network. Lagrangian tracer particles placed throughout the star record the temporal evolution of the initial simulation and enable the extension of the nuclear network evolution by incorporating larger systems in post-processing nucleosynthesis calculations. We present post-processing results of the four ab initio axisymmetric CCSN 2D models of Bruenn et al. (2013) evolved with the smaller α-network, and initiated from stellar metallicity, non-rotating progenitors of mass 12, 15, 20, and 25 M⊙ from Woosley & Heger (2007). As a test of the limitations of post-processing, we provide preliminary results from an ongoing simulation of the 15 M⊙ model evolved with a realistic 150 species nuclear reaction network in situ. With more accurate energy generation rates and an improved determination of the thermodynamic trajectories of the tracer particles, we can better unravel the complicated multidimensional "mass-cut" in CCSN simulations and probe for less energetically significant nuclear processes like the νp-process and the r-process, which require still larger networks.

76 FR 17712 - In the Matter of Entergy Nuclear Vermont Yankee, LLC and Entergy Nuclear Operations, Inc...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-03-30

... completed to the Commission's satisfaction: (1) The tritiated groundwater remediation process; (2) the soil remediation process scheduled to take place during the refueling outage, to remove soil containing tritium and... leakage into the surrounding soil, and therefore to the groundwater, from an unsealed joint in the...

Processing fissile material mixtures containing zirconium and/or carbon

DOEpatents

Johnson, Michael Ernest; Maloney, Martin David

2013-07-02

A method of processing spent TRIZO-coated nuclear fuel may include adding fluoride to complex zirconium present in a dissolved TRIZO-coated fuel. Complexing the zirconium with fluoride may reduce or eliminate the potential for zirconium to interfere with the extraction of uranium and/or transuranics from fission materials in the spent nuclear fuel.

Overview of U.S. nuclear launch safety approval process, supporting launch vehicle databook and probabilistic risk assessment methods

NASA Technical Reports Server (NTRS)

Reinhart, L. E.

2001-01-01

This paper provides an overview of the U.S. space nuclear power system launch approval process as defined by the two separate requirements of the National Environmental Policy Act (NEPA) and Presidential Directive/National Security Council Memorandum No. 25 (PD/NSC-25).

Nuclear Energy and Synthetic Liquid Transportation Fuels

NASA Astrophysics Data System (ADS)

McDonald, Richard

2012-10-01

This talk will propose a plan to combine nuclear reactors with the Fischer-Tropsch (F-T) process to produce synthetic carbon-neutral liquid transportation fuels from sea water. These fuels can be formed from the hydrogen and carbon dioxide in sea water and will burn to water and carbon dioxide in a cycle powered by nuclear reactors. The F-T process was developed nearly 100 years ago as a method of synthesizing liquid fuels from coal. This process presently provides commercial liquid fuels in South Africa, Malaysia, and Qatar, mainly using natural gas as a feedstock. Nuclear energy can be used to separate water into hydrogen and oxygen as well as to extract carbon dioxide from sea water using ion exchange technology. The carbon dioxide and hydrogen react to form synthesis gas, the mixture needed at the beginning of the F-T process. Following further refining, the products, typically diesel and Jet-A, can use existing infrastructure and can power conventional engines with little or no modification. We can then use these carbon-neutral liquid fuels conveniently long into the future with few adverse environmental impacts.

NOK mediates glycolysis and nuclear PDC associated histone acetylation.

PubMed

Shi, Wei-Ye; Yang, Xiao; Huang, Bo; Shen, Wen H; Liu, Li

2017-06-01

NOK is a potent oncogene that can transform normal cells to cancer cells. We hypothesized that NOK might impact cancer cell metabolism and histone acetylation. We show that NOK localizes in the mitochondria, and while it minimally impacts tricarboxylic acid (TCA) cycle, it markedly inhibits the process of electron transport and oxidative phosphorylation processes and dramatically enhances aerobic glycolysis in cancer cells. NOK promotes the mitochondrial-nuclear translocation of pyruvate dehydrogenase complex (PDC), and enhances histone acetylation in the nucleus. Together, these findings show that NOK mediates glycolysis and nuclear PDC associated histone acetylation.

10 CFR 820.20 - Purpose and scope.

Code of Federal Regulations, 2013 CFR

2013-01-01

... OF ENERGY PROCEDURAL RULES FOR DOE NUCLEAR ACTIVITIES Enforcement Process § 820.20 Purpose and scope... violations of the DOE Nuclear Safety Requirements, for determining, whether a violation has occurred, for... of a violation of: (1) Any DOE Nuclear Safety Requirement set forth in the Code of Federal...

10 CFR 820.20 - Purpose and scope.

Code of Federal Regulations, 2012 CFR

2012-01-01

... OF ENERGY PROCEDURAL RULES FOR DOE NUCLEAR ACTIVITIES Enforcement Process § 820.20 Purpose and scope... violations of the DOE Nuclear Safety Requirements, for determining, whether a violation has occurred, for... of a violation of: (1) Any DOE Nuclear Safety Requirement set forth in the Code of Federal...

10 CFR 820.20 - Purpose and scope.

Code of Federal Regulations, 2011 CFR

2011-01-01

... OF ENERGY PROCEDURAL RULES FOR DOE NUCLEAR ACTIVITIES Enforcement Process § 820.20 Purpose and scope... violations of the DOE Nuclear Safety Requirements, for determining, whether a violation has occurred, for... of a violation of: (1) Any DOE Nuclear Safety Requirement set forth in the Code of Federal...

10 CFR 820.20 - Purpose and scope.

Code of Federal Regulations, 2014 CFR

2014-01-01

... OF ENERGY PROCEDURAL RULES FOR DOE NUCLEAR ACTIVITIES Enforcement Process § 820.20 Purpose and scope... violations of the DOE Nuclear Safety Requirements, for determining, whether a violation has occurred, for... of a violation of: (1) Any DOE Nuclear Safety Requirement set forth in the Code of Federal...

10 CFR 74.81 - Inspections.

Code of Federal Regulations, 2014 CFR

2014-01-01

... where nuclear reactor fuel is fabricated or processed, each licensee shall upon request by the Director... 10 Energy 2 2014-01-01 2014-01-01 false Inspections. 74.81 Section 74.81 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Enforcement § 74.81...

10 CFR 50.36 - Technical specifications.

Code of Federal Regulations, 2013 CFR

2013-01-01

... nuclear reactors are limits upon important process variables that are found to be necessary to reasonably... Commission terminates the license for the reactor, except for nuclear power reactors licensed under § 50.21(b... for nuclear reactors are settings for automatic protective devices related to those variables having...

10 CFR 50.36 - Technical specifications.

Code of Federal Regulations, 2014 CFR

2014-01-01

... nuclear reactors are limits upon important process variables that are found to be necessary to reasonably... Commission terminates the license for the reactor, except for nuclear power reactors licensed under § 50.21(b... for nuclear reactors are settings for automatic protective devices related to those variables having...

10 CFR 50.36 - Technical specifications.

Code of Federal Regulations, 2012 CFR

2012-01-01

... nuclear reactors are limits upon important process variables that are found to be necessary to reasonably... Commission terminates the license for the reactor, except for nuclear power reactors licensed under § 50.21(b... for nuclear reactors are settings for automatic protective devices related to those variables having...

10 CFR 74.81 - Inspections.

Code of Federal Regulations, 2011 CFR

2011-01-01

... where nuclear reactor fuel is fabricated or processed, each licensee shall upon request by the Director... 10 Energy 2 2011-01-01 2011-01-01 false Inspections. 74.81 Section 74.81 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) MATERIAL CONTROL AND ACCOUNTING OF SPECIAL NUCLEAR MATERIAL Enforcement § 74.81...

Nuclear Safety

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silver, E G

This document is a review journal that covers significant developments in the field of nuclear safety. Its scope includes the analysis and control of hazards associated with nuclear energy, operations involving fissionable materials, and the products of nuclear fission and their effects on the environment. Primary emphasis is on safety in reactor design, construction, and operation; however, the safety aspects of the entire fuel cycle, including fuel fabrication, spent-fuel processing, nuclear waste disposal, handling of radioisotopes, and environmental effects of these operations, are also treated.

Nuclear Safety. Technical progress journal, April--June 1996: Volume 37, No. 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muhlheim, M D

1996-01-01

This journal covers significant issues in the field of nuclear safety. Its primary scope is safety in the design, construction, operation, and decommissioning of nuclear power reactors worldwide and the research and analysis activities that promote this goal, but it also encompasses the safety aspects of the entire nuclear fuel cycle, including fuel fabrication, spent-fuel processing and handling, nuclear waste disposal, the handling of fissionable materials and radioisotopes, and the environmental effects of all these activities.

Nuclear Safety. Technical progress journal, January--March 1994: Volume 35, No. 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silver, E G

1994-01-01

This is a journal that covers significant issues in the field of nuclear safety. Its primary scope is safety in the design, construction, operation, and decommissioning of nuclear power reactors worldwide and the research and analysis activities that promote this goal, but it also encompasses the safety aspects of the entire nuclear fuel cycle, including fuel fabrication, spent-fuel processing and handling, and nuclear waste disposal, the handling of fissionable materials and radioisotopes, and the environmental effects of all these activities.

Nuclear astrophysics in the laboratory and in the universe

DOE Office of Scientific and Technical Information (OSTI.GOV)

Champagne, A. E., E-mail: artc@physics.unc.edu; Iliadis, C.; Longland, R.

Nuclear processes drive stellar evolution and so nuclear physics, stellar models and observations together allow us to describe the inner workings of stars and their life stories. This Information on nuclear reaction rates and nuclear properties are critical ingredients in addressing most questions in astrophysics and often the nuclear database is incomplete or lacking the needed precision. Direct measurements of astrophysically-interesting reactions are necessary and the experimental focus is on improving both sensitivity and precision. In the following, we review recent results and approaches taken at the Laboratory for Experimental Nuclear Astrophysics (LENA, http://research.physics.unc.edu/project/nuclearastro/Welcome.html )

Comparison of effects of inhibitors of viral and cellular protein kinases on human cytomegalovirus disruption of nuclear lamina and nuclear egress.

PubMed

Sharma, Mayuri; Coen, Donald M

2014-09-01

Human cytomegalovirus (HCMV) kinase UL97 is required for efficient nuclear lamina disruption during nuclear egress. However, cellular protein kinase C (PKC) has been implicated in this process in other systems. Comparing the effects of UL97 and cellular kinase inhibitors on HCMV nuclear egress confirms a role for UL97 in lamina disruption and nuclear egress. A pan-PKC inhibitor did not affect lamina disruption but did reduce the number of cytoplasmic capsids more than the number of nuclear capsids. Copyright © 2014, American Society for Microbiology. All Rights Reserved.

Proceedings of the 21st DOE/NRC Nuclear Air Cleaning Conference; Sessions 1--8

DOE Office of Scientific and Technical Information (OSTI.GOV)

First, M.W.

1991-02-01

Separate abstracts have been prepared for the papers presented at the meeting on nuclear facility air cleaning technology in the following specific areas of interest: air cleaning technologies for the management and disposal of radioactive wastes; Canadian waste management program; radiological health effects models for nuclear power plant accident consequence analysis; filter testing; US standard codes on nuclear air and gas treatment; European community nuclear codes and standards; chemical processing off-gas cleaning; incineration and vitrification; adsorbents; nuclear codes and standards; mathematical modeling techniques; filter technology; safety; containment system venting; and nuclear air cleaning programs around the world. (MB)

Genome-wide screen uncovers novel pathways for tRNA processing and nuclear-cytoplasmic dynamics.

PubMed

Wu, Jingyan; Bao, Alicia; Chatterjee, Kunal; Wan, Yao; Hopper, Anita K

2015-12-15

Transfer ribonucleic acids (tRNAs) are essential for protein synthesis. However, key gene products involved in tRNA biogenesis and subcellular movement remain to be discovered. We conducted the first comprehensive unbiased analysis of the role of nearly an entire proteome in tRNA biology and describe 162 novel and 12 previously known Saccharomyces cerevisiae gene products that function in tRNA processing, turnover, and subcellular movement. tRNA nuclear export is of particular interest because it is essential, but the known tRNA exporters (Los1 [exportin-t] and Msn5 [exportin-5]) are unessential. We report that mutations of CRM1 (Exportin-1), MEX67/MTR2 (TAP/p15), and five nucleoporins cause accumulation of unspliced tRNA, a hallmark of defective tRNA nuclear export. CRM1 mutation genetically interacts with los1Δ and causes altered tRNA nuclear-cytoplasmic distribution. The data implicate roles for the protein and mRNA nuclear export machineries in tRNA nuclear export. Mutations of genes encoding actin cytoskeleton components and mitochondrial outer membrane proteins also cause accumulation of unspliced tRNA, likely due to defective splicing on mitochondria. Additional gene products, such as chromatin modification enzymes, have unanticipated effects on pre-tRNA end processing. Thus, this genome-wide screen uncovered putative novel pathways for tRNA nuclear export and extensive links between tRNA biology and other aspects of cell physiology. © 2015 Wu et al.; Published by Cold Spring Harbor Laboratory Press.

Influence of nuclear exchange on nonadiabatic electron processes in H(+)+H2 collisions.

PubMed

Errea, L F; Illescas, Clara; Macías, A; Méndez, L; Pons, B; Rabadán, I; Riera, A

2010-12-28

H(+)+H(2) collisions are studied by means of a semiclassical approach that explicitly accounts for nuclear rearrangement channels in nonadiabatic electron processes. A set of classical trajectories is used to describe the nuclear motion, while the electronic degrees of freedom are treated quantum mechanically in terms of a three-state expansion of the collision wavefunction. We describe electron capture and vibrational excitation, which can also involve nuclear exchange and dissociation, in the E = 2-1000 eV impact energy range. We compare dynamical results obtained with two parametrizations of the potential energy surface of H(3)(+) ground electronic state. Total cross sections for E > 10 eV agree with previous results using a vibronic close-coupling expansion, and with experimental data for E < 10 eV. Additionally, some prototypical features of both nuclear and electron dynamics at low E are discussed.

Somatic cell cloning: the ultimate form of nuclear reprogramming?

PubMed

Piedrahita, Jorge A; Mir, Bashir; Dindot, Scott; Walker, Shawn

2004-05-01

With the increasing difficulties associated with meeting the required needs for organs used in transplantation, alternative approaches need to be considered. These include the use of stem cells as potential sources of specialized cells, the ability to transdifferentiate cell types in culture, and the development of complete organs that can be used in humans. All of the above goals will require a complete understanding of the factors affecting cell differentiation and nuclear reprogramming. To make this a reality, however, techniques associated with cloning and genetic modifications in somatic cells need to be continued to be developed and optimized. This includes not only an enhancement of the rate of homologous recombination in somatic cells, but also a thorough understanding of the nuclear reprogramming process taking place during nuclear transfer. The understanding of this process is likely to have an effect beyond the area of nuclear transfer and assist with better methods for transdifferentiation of mammalian cells.

The nuclear proteome of Trypanosoma brucei

PubMed Central

Goos, Carina; Dejung, Mario; Janzen, Christian J.; Butter, Falk

2017-01-01

Trypanosoma brucei is a protozoan flagellate that is transmitted by tsetse flies into the mammalian bloodstream. The parasite has a huge impact on human health both directly by causing African sleeping sickness and indirectly, by infecting domestic cattle. The biology of trypanosomes involves some highly unusual, nuclear-localised processes. These include polycistronic transcription without classical promoters initiated from regions defined by histone variants, trans-splicing of all transcripts to the exon of a spliced leader RNA, transcription of some very abundant proteins by RNA polymerase I and antigenic variation, a switch in expression of the cell surface protein variants that allows the parasite to resist the immune system of its mammalian host. Here, we provide the nuclear proteome of procyclic Trypanosoma brucei, the stage that resides within the tsetse fly midgut. We have performed quantitative label-free mass spectrometry to score 764 significantly nuclear enriched proteins in comparison to whole cell lysates. A comparison with proteomes of several experimentally characterised nuclear and non-nuclear structures and pathways confirmed the high quality of the dataset: the proteome contains about 80% of all nuclear proteins and less than 2% false positives. Using motif enrichment, we found the amino acid sequence KRxR present in a large number of nuclear proteins. KRxR is a sub-motif of a classical eukaryotic monopartite nuclear localisation signal and could be responsible for nuclear localization of proteins in Kinetoplastida species. As a proof of principle, we have confirmed the nuclear localisation of six proteins with previously unknown localisation by expressing eYFP fusion proteins. While proteome data of several T. brucei organelles have been published, our nuclear proteome closes an important gap in knowledge to study trypanosome biology, in particular nuclear-related processes. PMID:28727848

Production of nuclear grade zirconium: A review

NASA Astrophysics Data System (ADS)

Xu, L.; Xiao, Y.; van Sandwijk, A.; Xu, Q.; Yang, Y.

2015-11-01

Zirconium is an ideal material for nuclear reactors due to its low absorption cross-section for thermal neutrons, whereas the typically contained hafnium with strong neutron-absorption is very harmful for zirconium as a fuel cladding material. This paper provides an overview of the processes for nuclear grade zirconium production with emphasis on the methods of Zr-Hf separation. The separation processes are roughly classified into hydro- and pyrometallurgical routes. The known pyrometallurgical Zr-Hf separation methods are discussed based on the following reaction features: redox characteristics, volatility, electrochemical properties and molten salt-metal equilibrium. In the present paper, the available Zr-Hf separation technologies are compared. The advantages and disadvantages as well as future directions of research and development for nuclear grade zirconium production are discussed.

Development of automation software for neutron activation analysis process in Malaysian nuclear agency

NASA Astrophysics Data System (ADS)

Yussup, N.; Rahman, N. A. A.; Ibrahim, M. M.; Mokhtar, M.; Salim, N. A. A.; Soh@Shaari, S. C.; Azman, A.

2017-01-01

Neutron Activation Analysis (NAA) process has been established in Malaysian Nuclear Agency (Nuclear Malaysia) since 1980s. Most of the procedures established especially from sample registration to sample analysis are performed manually. These manual procedures carried out by the NAA laboratory personnel are time consuming and inefficient. Hence, a software to support the system automation is developed to provide an effective method to replace redundant manual data entries and produce faster sample analysis and calculation process. This paper describes the design and development of automation software for NAA process which consists of three sub-programs. The sub-programs are sample registration, hardware control and data acquisition; and sample analysis. The data flow and connection between the sub-programs will be explained. The software is developed by using National Instrument LabView development package.

NUCLEAR CLEANUP: Progress Made at Rocky Flats, but Closure by 2006 Is Unlikely, and Costs May Increase

DTIC Science & Technology

2001-02-01

liquids or residues from process pipes and tanks. The contractor also dismantled plutonium - processing furnaces, stripped out contaminated process...Soil Cleanup Levels on the Scope and Cost of the 903 Pad Cleanup 30 Figures Figure 1: Workers in Protective Clothing Handling Plutonium - Contaminated ...activities—shipping nuclear materials such as plutonium - contaminated metals and powders—is expected to be completed in 2002. Another activity

15 CFR 742.19 - Anti-terrorism: North Korea.

Code of Federal Regulations, 2010 CFR

2010-01-01

...-users or nuclear end-uses. Applications for non-nuclear end-users or for non-nuclear end-uses, excluding... Korea under section 6(a) of the EAA. License applications for items reviewed under section 6(a) controls... processing license applications for items controlled under EAA section 6(j).) (b) Licensing policy. (1...

15 CFR 742.19 - Anti-terrorism: North Korea.

Code of Federal Regulations, 2011 CFR

2011-01-01

... reexport is destined to nuclear end-users or nuclear end-uses. Applications for non-nuclear end-users or... Korea under section 6(a) of the EAA. License applications for items reviewed under section 6(a) controls... processing license applications for items controlled under EAA section 6(j).) (b) Licensing policy. (1...

Talk About Nuclear Power

ERIC Educational Resources Information Center

Tremlett, Lewis

1976-01-01

Presents an overview of the relation of nuclear power to human health and the environment, and discusses the advantages and disadvantages of nuclear power as an energy source urging technical educators to inculcate an awareness of the problems associated with the production of energy. Describes the fission reaction process, the hazards of…

A new application of the phase-field method for understanding the mechanisms of nuclear architecture reorganization.

PubMed

Lee, S Seirin; Tashiro, S; Awazu, A; Kobayashi, R

2017-01-01

Specific features of nuclear architecture are important for the functional organization of the nucleus, and chromatin consists of two forms, heterochromatin and euchromatin. Conventional nuclear architecture is observed when heterochromatin is enriched at nuclear periphery, and it represents the primary structure in the majority of eukaryotic cells, including the rod cells of diurnal mammals. In contrast to this, inverted nuclear architecture is observed when the heterochromatin is distributed at the center of the nucleus, which occurs in the rod cells of nocturnal mammals. The inverted architecture found in the rod cells of the adult mouse is formed through the reorganization of conventional architecture during terminal differentiation. Although a previous experimental approach has demonstrated the relationship between these two nuclear architecture types at the molecular level, the mechanisms underlying long-range reorganization processes remain unknown. The details of nuclear structures and their spatial and temporal dynamics remain to be elucidated. Therefore, a comprehensive approach, using mathematical modeling, is required, in order to address these questions. Here, we propose a new mathematical approach to the understanding of nuclear architecture dynamics using the phase-field method. We successfully recreated the process of nuclear architecture reorganization, and showed that it is robustly induced by physical features, independent of a specific genotype. Our study demonstrates the potential of phase-field method application in the life science fields.

Integrated nuclear data utilisation system for innovative reactors.

PubMed

Yamano, N; Hasegawa, A; Kato, K; Igashira, M

2005-01-01

A five-year research and development project on an integrated nuclear data utilisation system was initiated in 2002, for developing innovative nuclear energy systems such as accelerator-driven systems. The integrated nuclear data utilisation system will be constructed as a modular code system, which consists of two sub-systems: the nuclear data search and plotting sub-system, and the nuclear data processing and utilisation sub-system. The system will be operated with a graphical user interface in order to enable easy utilisation through the Internet by both nuclear design engineers and nuclear data evaluators. This paper presents an overview of the integrated nuclear data utilisation system, describes the development of a prototype system to examine the operability of the user interface and discusses specifications of the two sub-systems.

Energy Production and Transmutation of Nuclear Waste by Accelerator Driven Systems

NASA Astrophysics Data System (ADS)

Zhivkov, P. K.

2018-05-01

There is a significant amount of highly radiotoxic long-life nuclear waste (NW) produced by NPP (Nuclear Power Plants). Transmutation is a process which transforms NW into less radiotoxic nuclides with a shorter period of half-life by spallation neutrons or radiative capture of neutrons produced by ADS (Accelerator Driven System). In the processes of transmutation new radioactive nuclides are produced. ADS is big energy consumer equipment. It is a method for production of a high-flux and high-energy neutron field. All these processes occur in ADS simultaneously. ADS is able to transmute actinides and produce energy simultaneously. The article considers the energy production problems in ADS. Several ideas are developed regarding the solution of the global energy supply.

On the electrophilic character of molecules through its relation with electronegativity and chemical hardness.

PubMed

Islam, Nazmul; Ghosh, Dulal C

2012-01-01

Electrophilicity is an intrinsic property of atoms and molecules. It probably originates logistically with the involvement in the physical process of electrostatics of soaked charge in electronic shells and the screened nuclear charge of atoms. Motivated by the existing view of conceptual density functional theory that similar to electronegativity and hardness equalization, there should be a physical process of equalization of electrophilicity during the chemical process of formation of hetero nuclear molecules, we have developed a new theoretical scheme and formula for evaluating the electrophilicity of hetero nuclear molecules. A comparative study with available bench marking reveals that the hypothesis of electrophilicity and equalization, and the present method of evaluating equalized electrophilicity, are scientifically promising.

On the Electrophilic Character of Molecules Through Its Relation with Electronegativity and Chemical Hardness

PubMed Central

Islam, Nazmul; Ghosh, Dulal C.

2012-01-01

Electrophilicity is an intrinsic property of atoms and molecules. It probably originates logistically with the involvement in the physical process of electrostatics of soaked charge in electronic shells and the screened nuclear charge of atoms. Motivated by the existing view of conceptual density functional theory that similar to electronegativity and hardness equalization, there should be a physical process of equalization of electrophilicity during the chemical process of formation of hetero nuclear molecules, we have developed a new theoretical scheme and formula for evaluating the electrophilicity of hetero nuclear molecules. A comparative study with available bench marking reveals that the hypothesis of electrophilicity and equalization, and the present method of evaluating equalized electrophilicity, are scientifically promising. PMID:22408445

Apoptosis leads to a degradation of vital components of active nuclear transport and a dissociation of the nuclear lamina.

PubMed

Kramer, A; Liashkovich, I; Oberleithner, H; Ludwig, S; Mazur, I; Shahin, V

2008-08-12

Apoptosis, a physiologically critical process, is characterized by a destruction of the cell after sequential degradation of key cellular components. Here, we set out to explore the fate of the physiologically indispensable nuclear envelope (NE) in this process. The NE mediates the critical nucleocytoplasmic transport through nuclear pore complexes (NPCs). In addition, the NE is involved in gene expression and contributes significantly to the overall structure and mechanical stability of the cell nucleus through the nuclear lamina, which underlies the entire nucleoplasmic face of the NE and thereby interconnects the NPCs, the NE, and the genomic material. Using the nano-imaging and mechanical probing approach atomic force microscopy (AFM) and biochemical methods, we unveiled the fate of the NE during apoptosis. The doomed NE sustains a degradation of both the mediators of the critical selective nucleocytoplasmic transport, namely NPC cytoplasmic filaments and basket, and the nuclear lamina. These observations are paralleled by marked softening and destabilization of the NE and the detection of vesicle-like nuclear fragments. We conclude that destruction of the cell nucleus during apoptosis proceeds in a strategic fashion. Degradation of NPC cytoplasmic filaments and basket shuts down the critical selective nucleocytoplasmic cross-talk. Degradation of the nuclear lamina disrupts the pivotal connection between the NE and the chromatin, breaks up the overall nuclear architecture, and softens the NE, thereby enabling the formation of nuclear fragments at later stages of apoptosis.

High-fidelity readout and control of a nuclear spin qubit in silicon.

PubMed

Pla, Jarryd J; Tan, Kuan Y; Dehollain, Juan P; Lim, Wee H; Morton, John J L; Zwanenburg, Floris A; Jamieson, David N; Dzurak, Andrew S; Morello, Andrea

2013-04-18

Detection of nuclear spin precession is critical for a wide range of scientific techniques that have applications in diverse fields including analytical chemistry, materials science, medicine and biology. Fundamentally, it is possible because of the extreme isolation of nuclear spins from their environment. This isolation also makes single nuclear spins desirable for quantum-information processing, as shown by pioneering studies on nitrogen-vacancy centres in diamond. The nuclear spin of a (31)P donor in silicon is very promising as a quantum bit: bulk measurements indicate that it has excellent coherence times and silicon is the dominant material in the microelectronics industry. Here we demonstrate electrical detection and coherent manipulation of a single (31)P nuclear spin qubit with sufficiently high fidelities for fault-tolerant quantum computing. By integrating single-shot readout of the electron spin with on-chip electron spin resonance, we demonstrate quantum non-demolition and electrical single-shot readout of the nuclear spin with a readout fidelity higher than 99.8 percent-the highest so far reported for any solid-state qubit. The single nuclear spin is then operated as a qubit by applying coherent radio-frequency pulses. For an ionized (31)P donor, we find a nuclear spin coherence time of 60 milliseconds and a one-qubit gate control fidelity exceeding 98 percent. These results demonstrate that the dominant technology of modern electronics can be adapted to host a complete electrical measurement and control platform for nuclear-spin-based quantum-information processing.

Feasibility study of a gamma camera for monitoring nuclear materials in the PRIDE facility

NASA Astrophysics Data System (ADS)

Jo, Woo Jin; Kim, Hyun-Il; An, Su Jung; Lee, Chae Young; Song, Han-Kyeol; Chung, Yong Hyun; Shin, Hee-Sung; Ahn, Seong-Kyu; Park, Se-Hwan

2014-05-01

The Korea Atomic Energy Research Institute (KAERI) has been developing pyroprocessing technology, in which actinides are recovered together with plutonium. There is no pure plutonium stream in the process, so it has an advantage of proliferation resistance. Tracking and monitoring of nuclear materials through the pyroprocess can significantly improve the transparency of the operation and safeguards. An inactive engineering-scale integrated pyroprocess facility, which is the PyRoprocess Integrated inactive DEmonstration (PRIDE) facility, was constructed to demonstrate engineering-scale processes and the integration of each unit process. the PRIDE facility may be a good test bed to investigate the feasibility of a nuclear material monitoring system. In this study, we designed a gamma camera system for nuclear material monitoring in the PRIDE facility by using a Monte Carlo simulation, and we validated the feasibility of this system. Two scenarios, according to locations of the gamma camera, were simulated using GATE (GEANT4 Application for Tomographic Emission) version 6. A prototype gamma camera with a diverging-slat collimator was developed, and the simulated and experimented results agreed well with each other. These results indicate that a gamma camera to monitor the nuclear material in the PRIDE facility can be developed.

Measurement of Quark Energy Loss in Cold Nuclear Matter at Fermilab E906/SeaQuest

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lin, Po-Ju

Parton energy loss is a process within QCD that draws considerable interest. The measurement of parton energy loss can provide valuable information for other hard-scattering processes in nuclei, and also serves as an important tool for exploring the properties of the quark-gluon plasma (QGP). Quantifying the energy loss in cold nuclear matter will help to set a baseline relative to energy loss in the QGP. With the Drell-Yan process, the energy loss of incoming quarks in cold nuclear matter can be ideally investigated since the final state interaction is expected to be minimal. E906/SeaQuest is a fixed-target experiment using themore » 120 GeV proton beam from the Fermilab Main Injector and has been collecting data from p+p, p+d, p+C, p+Fe, and p+W collisions. Within the E906 kinematic coverage of Drell-Yan production via the dimuon channel, the quark energy loss can be measured in a regime where other nuclear effects are expected to be small. In this thesis, the study of quark ener gy loss from different cold nuclear targets is presented.« less

Managing nuclear power plant induced disasters.

PubMed

Kyne, Dean

2015-01-01

To understand the management process of nuclear power plant (NPP) induced disasters. The study shields light on phases and issues associated with the NPP induced disaster management. This study uses Palo Verde Nuclear Generation Station as study subject and Arizona State as study area. This study uses the Radiological Assessment System for Consequence Analysis (RASCAL) Source Term to Dose (STDose) of the Nuclear Regulatory Commission, a computer software to project and assess the source term dose and release pathway. This study also uses ArcGIS, a geographic information system to analyze geospatial data. A detailed case study of Palo Verde Nuclear Power Generation (PVNPG) Plant was conducted. The findings reveal that the NPP induced disaster management process is conducted by various stakeholders. To save lives and to minimize the impacts, it is vital to relate planning and process of the disaster management. Number of people who expose to the radioactive plume pathway and level of radioactivity could vary depending on the speed and direction of wind on the day the event takes place. This study findings show that there is a need to address the burning issue of different racial and ethnic groups' unequal exposure and unequal protection to potential risks associated with the NPPs.

Development of High Fidelity, Fuel-Like Thermal Simulators for Non-Nuclear Testing

NASA Technical Reports Server (NTRS)

Bragg-Sitton, S. M.; Farmer, J.; Dixon, D.; Kapernick, R.; Dickens, R.; Adams, M.

2007-01-01

Non-nuclear testing can be a valuable tool in development of a space nuclear power or propulsion system. In a non-nuclear test bed, electric heaters are used to simulate the heat from nuclear fuel. Work at the NASA Marshall Space Flight Center seeks to develop high fidelity thermal simulators that not only match the static power profile that would be observed in an operating, fueled nuclear reactor, but to also match the dynamic fuel pin performance during feasible transients. Comparison between the fuel pins and thermal simulators is made at the fuel clad surface, which corresponds to the sheath surface in the thermal simulator. Static and dynamic fuel pin performance was determined using SINDA-FLUINT analysis, and the performance of conceptual thermal simulator designs was compared to the expected nuclear performance. Through a series of iterative analysis, a conceptual high fidelity design will be developed, followed by engineering design, fabrication, and testing to validate the overall design process. Although the resulting thermal simulator will be designed for a specific reactor concept, establishing this rigorous design process will assist in streamlining the thermal simulator development for other reactor concepts.

Irradiation pretreatment for coal desulfurization

NASA Technical Reports Server (NTRS)

Hsu, G. C.

1979-01-01

Process using highly-penetrating nuclear radiation (Beta and Gamma radiation) from nuclear power plant radioactive waste to irradiate coal prior to conventional desulfurization procedures increases total extraction of sulfur.

2012 Special NSREC Issue of the IEEE Transactions on Nuclear Science Comments by the Editors

NASA Astrophysics Data System (ADS)

Schwank, Jim; Brown, Dennis; Girard, Sylvain; Gouker, Pascale; Gerardin, Simone; Quinn, Heather; Barnaby, Hugh

2012-12-01

The December 2012 special issue of the IEEE Transactions on Nuclear Science contains selected papers from the 49th annual IEEE International Nuclear and Space Radiation Effects Conference (NSREC) held July 16-20, 2012, in Miami, Florida USA. 95 papers presented at the 2012 NSREC were submitted for consideration for this year’s special issue. Those papers that appear in this special issue were able to successfully complete the review process before the deadline for the December issue. A few additional papers may appear in subsequent issues of the TRANSACTIONS. This publication is the premier archival journal for research on space and nuclear radiation effects in materials, devices, circuits, and systems. This distinction is the direct result of the conscientious efforts of both the authors, who present and document their work, and the reviewers, who selflessly volunteer their time and talent to help review the manuscripts. Each paper in this journal has been reviewed by experts selected by the editors for their expertise and knowledge of the particular subject areas. The peer review process for a typical technical journal generally takes six months to one year to complete. To publish this special issue of the IEEE Transactions on Nuclear Science (in December), the review process, from initial submission to final form, must be completed in about 10 weeks. Because of the short schedule, both the authors and reviewers are required to respond very quickly. The reviewers listed on the following pages contributed vitally to this quick-turn review process.We would like to express our sincere appreciation to each of them for accepting this difficult, but critical role in the process. To provide consistent reviews of papers throughout the year, the IEEE Transactions on Nuclear Science relies on a year-round editorial board that manages reviews for submissions throughout the year to the TRANSACTIONS in the area of radiation effects. The review process is managed by a Senior Editor and six Associate Editors who are technically knowledgeable in one or more specializations and are experienced in the publication process. This editorial process works very well. With twice the number of editors as previously used for overseeing the review process, each editor is able to devote more time to individual papers.

Potential Signatures of Semi-volatile Compounds Associated With Nuclear Processing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Probasco, Kathleen M.; Birnbaum, Jerome C.; Maughan, A. D.

2002-06-01

Semi-volatile chemicals associated with nuclear processes (e.g., the reprocessing of uranium to produce plutonium for nuclear weapons, or the separation of actinides from processing waste streams), can provide sticky residues or signatures that will attach to piping, ducting, soil, water, or other surface media. Volatile compounds, that are more suitable for electro-optical sensing, have been well studied. However, the semi-volatile compounds have not been well documented or studied. A majority of these semi-volatile chemicals are more robust than typical gaseous or liquid chemicals and can have lifetimes of several weeks, months, or years in the environment. However, large data gapsmore » exist concerning these potential signature compounds and more research is needed to fill these data gaps so that important signature information is not overlooked or discarded. This report investigates key semi-volatile compounds associated with nuclear separations, identifies available chemical and physical properties, and discusses the degradation products that would result from hydrolysis, radiolysis and oxidation reactions on these compounds.« less

Interdependence between transcription and mRNP processing and export, and its impact on genetic stability.

PubMed

Luna, Rosa; Jimeno, Sonia; Marín, Mercedes; Huertas, Pablo; García-Rubio, María; Aguilera, Andrés

2005-06-10

The conserved eukaryotic THO-TREX complex acts at the interface between transcription and mRNA export and affects transcription-associated recombination. To investigate the interdependence of nuclear mRNA processes and their impact on genomic integrity, we analyzed transcript accumulation and recombination of 40 selected mutants covering representative steps of the biogenesis and export of the messenger ribonucleoprotein particle (mRNP). None of the mutants analyzed shared the strong transcript-accumulation defect and hyperrecombination of THO mutants. Nevertheless, mutants in 3' end cleavage/polyadenylation, nuclear exosome, and mRNA export showed a weak but significant effect on recombination and transcript accumulation. Mutants of the nuclear exosome (rrp6) and 3' end processing factors (rna14 and rna15) showed inefficient transcription elongation and genetic interactions with THO. The results suggest a tight interdependence among mRNP biogenesis steps and transcription and an unexpected effect of the nuclear exosome and the cleavage/polyadenylation factors on transcription elongation and genetic integrity.

Process for estimating likelihood and confidence in post detonation nuclear forensics.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Darby, John L.; Craft, Charles M.

2014-07-01

Technical nuclear forensics (TNF) must provide answers to questions of concern to the broader community, including an estimate of uncertainty. There is significant uncertainty associated with post-detonation TNF. The uncertainty consists of a great deal of epistemic (state of knowledge) as well as aleatory (random) uncertainty, and many of the variables of interest are linguistic (words) and not numeric. We provide a process by which TNF experts can structure their process for answering questions and provide an estimate of uncertainty. The process uses belief and plausibility, fuzzy sets, and approximate reasoning.

Hanford Spent Nuclear Fuel Project recommended path forward

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fulton, J.C.

The Spent Nuclear Fuel Project (the Project), in conjunction with the U.S. Department of Energy-commissioned Independent Technical Assessment (ITA) team, has developed engineered alternatives for expedited removal of spent nuclear fuel, including sludge, from the K Basins at Hanford. These alternatives, along with a foreign processing alternative offered by British Nuclear Fuels Limited (BNFL), were extensively reviewed and evaluated. Based on these evaluations, a Westinghouse Hanford Company (WHC) Recommended Path Forward for K Basins spent nuclear fuel has been developed and is presented in Volume I of this document. The recommendation constitutes an aggressive series of projects to construct andmore » operate systems and facilities to safely retrieve, package, transport, process, and store K Basins fuel and sludge. The overall processing and storage scheme is based on the ITA team`s proposed passivation and vault storage process. A dual purpose staging and vault storage facility provides an innovative feature which allows accelerated removal of fuel and sludge from the basins and minimizes programmatic risks beyond any of the originally proposed alternatives. The projects fit within a regulatory and National Environmental Policy Act (NEPA) overlay which mandates a two-phased approach to construction and operation of the needed facilities. The two-phase strategy packages and moves K Basins fuel and sludge to a newly constructed Staging and Storage Facility by the year 2000 where it is staged for processing. When an adjoining facility is constructed, the fuel is cycled through a stabilization process and returned to the Staging and Storage Facility for dry interim (40-year) storage. The estimated total expenditure for this Recommended Path Forward, including necessary new construction, operations, and deactivation of Project facilities through 2012, is approximately $1,150 million (unescalated).« less

The use of nuclear data in the field of nuclear fuel recycling

NASA Astrophysics Data System (ADS)

Martin, Julie-Fiona; Launay, Agnès; Grassi, Gabriele; Binet, Christophe; Lelandais, Jacques; Lecampion, Erick

2017-09-01

AREVA NC La Hague facility is the first step of the nuclear fuel recycling process implemented in France. The processing of the used fuel is governed by high standards of criticality-safety, and strong expectations on the quality of end-products. From the received used fuel assemblies, the plutonium and the uranium are extracted for further energy production purposes within the years following the reprocessing. Furthermore, the ultimate waste - fission products and minor actinides on the one hand, and hulls and end-pieces on the other hand - is adequately packaged for long term disposal. The used fuel is therefore separated into very different materials, and time scales which come into account may be longer than in some other nuclear fields of activity. Given the variety of the handled nuclear materials, as well as the time scales at stake, the importance given to some radionuclides, and hence to the associated nuclear data, can also be specific to the AREVA NC La Hague plant. A study has thus been led to identify a list of the most important radionuclides for the AREVA NC La Hague plant applications, relying on the running constraints of the facility, and the end-products expectations. The activities at the AREVA NC La Hague plant are presented, and the methodology to extract the most important radionuclides for the reprocessing process is detailed.

The Acceptance Strategy for Nuclear Power Plant In Indonesia

NASA Astrophysics Data System (ADS)

Suhaemi, Tjipta; Syaukat, Achmad

2010-06-01

THE ACCEPTANCE STRATEGY FOR NUCLEAR POWER PLANT IN INDONESIA. Indonesia has planned to build nuclear power plants. Some feasibility studies have been conducted intensively. However, the processes of NPP introduction are still uncertain. National Energy Plan in Indonesia, which has been made by some governmental agencies, does not yet give positive impact to the government decision to construct the nuclear power plant (NPP). This paper discusses the process of NPP introduction in Indonesia, which has been colored with debate of stakeholder and has delayed decision for go-nuclear. The technology paradigm is used to promote NPP as an alternative of reliable energy resources. This paradigm should be complemented with international politic-economic point of view. The international politic-economic point of view shows that structural powers, consisting of security, production, finance, and knowledge structures, within which the NPP is introduced, have dynamic characteristics. The process of NPP introduction in Indonesia contains some infrastructure development (R&D, legislation, regulation, energy planning, site study, public acceptance efforts, etc), but they need a better coherent NPP implementation program and NPP Acceptance Program. Strategic patterns for NPP acceptance described in this paper are made by considering nuclear regulation development and the interest of basic domestic participation. The first NPP program in Indonesia having proven technology and basic domestic participation is and important milestone toward and optimal national energy-mix.

Recapturing Graphite-Based Fuel Element Technology for Nuclear Thermal Propulsion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trammell, Michael P; Jolly, Brian C; Miller, James Henry

ORNL is currently recapturing graphite based fuel forms for Nuclear Thermal Propulsion (NTP). This effort involves research and development on materials selection, extrusion, and coating processes to produce fuel elements representative of historical ROVER and NERVA fuel. Initially, lab scale specimens were fabricated using surrogate oxides to develop processing parameters that could be applied to full length NTP fuel elements. Progress toward understanding the effect of these processing parameters on surrogate fuel microstructure is presented.

Electron Beam Welding: study of process capability and limitations towards development of nuclear components

NASA Astrophysics Data System (ADS)

Vadolia, Gautam R.; Premjit Singh, K.

2017-04-01

Electron Beam Welding (EBW) technology is an established and widely adopted technique in nuclear research and development area. Electron beam welding was thought of as a candidate process for ITER Vacuum Vessel Fabrication. Dhruva Reactor at BARC, Mumbai and Niobium superconducting accelerator cavity at BARC has adopted the EB welding technique as a fabrication route. Study of process capability and limitations based on available literature is consolidated in this short review paper.

10 CFR 70.60 - Applicability.

Code of Federal Regulations, 2011 CFR

2011-01-01

... Certain Licensees Authorized To Possess a Critical Mass of Special Nuclear Material § 70.60 Applicability... critical mass of special nuclear material, and engaged in enriched uranium processing, fabrication of...

Strategic policy and process: An assessment of the evolution of American nuclear strategy, its determinants, and its implications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lehman, C.M.

1993-01-01

This dissertation examines the evolution of American strategic nuclear policy with particular emphasis on the substantial change in nuclear doctrine which occurred during the first and second Administrations of President Richard M. Nixon. The dissertation argues that this period saw the emergence of a new and substantially different strategic nuclear policy which changed fundamentally the basis upon which America's nuclear deterrence rested. It argues, further, that this policy has remained largely unchanged through the course of five succeeding administrations. The dissertation describes and analyzes the evolution of the defense policy formulation process of the United States government from the yearsmore » of the Truman Administration to the Bush Administration. Primary attention is directed towards identifying the specific policies of each Administration highlighting the factors which appear to have been the most significant in prompting changes in American strategic nuclear policy. An in-depth examination of strategic nuclear policy formulation and implementation is provided for the period of the Nixon Administration. The Administration's policies are analyzed and the full constellation of forces that brought about a major adjustment in the strategic nuclear policy of the Unites States are identified and analyzed. Particular emphasis is placed on tracking and assessing the role that Congress has played in the development of nuclear policy before, during, and after Nixon years. Specific attention is directed to defining the [open quotes]determinants[close quotes] of strategic nuclear policy and to a careful delineation of the dangers associated with a divergence between public policy pronouncements an the actual employment or targeting practices governing the potential use of nuclear weapons. A final section draws conclusions and postulates several basic guidelines for the formulation of future US strategic nuclear policy.« less

Quantum Information Processing with Large Nuclear Spins in GaAs Semiconductors

NASA Astrophysics Data System (ADS)

Leuenberger, Michael N.; Loss, Daniel; Poggio, M.; Awschalom, D. D.

2002-10-01

We propose an implementation for quantum information processing based on coherent manipulations of nuclear spins I=3/2 in GaAs semiconductors. We describe theoretically an NMR method which involves multiphoton transitions and which exploits the nonequidistance of nuclear spin levels due to quadrupolar splittings. Starting from known spin anisotropies we derive effective Hamiltonians in a generalized rotating frame, valid for arbitrary I, which allow us to describe the nonperturbative time evolution of spin states generated by magnetic rf fields. We identify an experimentally observable regime for multiphoton Rabi oscillations. In the nonlinear regime, we find Berry phase interference.

Caustic Precipitation of Plutonium Using Gadolinium as the Neutron Poison for Disposition to High Level Waste

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bronikowski, M.G.

2002-06-24

Nuclear Materials Management Division (NMMD) has proposed that up to 100 kg of the plutonium (Pu) solutions stored in H-Canyon be precipitated with a nuclear poison and dispositioned to H-Area Tank Farm. The use of gadolinium (Gd) as the poison would greatly reduce the number of additional glass logs resulting from this disposition. This report summarizes the characteristics of the precipitation process and addresses criticality concerns in the Nuclear Criticality Safety Evaluation. No problems were found with the nature of the precipitate or the neutralization process.

Nuclear positioning by actin cables and perinuclear actin

PubMed Central

Huelsmann, Sven; Brown, Nicholas H

2014-01-01

Nuclear positioning is an important process during development and homeostasis. Depending on the affected tissue, mislocalized nuclei can alter cellular processes such as polarization, differentiation, or migration and lead ultimately to diseases. Many cells actively control the position of their nucleus using their cytoskeleton and motor proteins. We have recently shown that during Drosophila oogenesis, nurse cells employ cytoplasmic actin cables in association with perinuclear actin to position their nucleus. Here, we briefly summarize our work and discuss why nuclear positioning in nurse cells is specialized but the molecular mechanisms are likely to be more generally used. PMID:24905988

Nuclear positioning by actin cables and perinuclear actin: Special and general?

PubMed

Huelsmann, Sven; Brown, Nicholas H

2014-01-01

Nuclear positioning is an important process during development and homeostasis. Depending on the affected tissue, mislocalized nuclei can alter cellular processes such as polarization, differentiation, or migration and lead ultimately to diseases. Many cells actively control the position of their nucleus using their cytoskeleton and motor proteins. We have recently shown that during Drosophila oogenesis, nurse cells employ cytoplasmic actin cables in association with perinuclear actin to position their nucleus. Here, we briefly summarize our work and discuss why nuclear positioning in nurse cells is specialized but the molecular mechanisms are likely to be more generally used.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pritychenko, B., E-mail: pritychenko@bnl.go; Mughaghab, S.F.; Sonzogni, A.A.

We have calculated the Maxwellian-averaged cross sections and astrophysical reaction rates of the stellar nucleosynthesis reactions (n, {gamma}), (n, fission), (n, p), (n, {alpha}), and (n, 2n) using the ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, and ENDF/B-VI.8 evaluated nuclear reaction data libraries. These four major nuclear reaction libraries were processed under the same conditions for Maxwellian temperatures (kT) ranging from 1 keV to 1 MeV. We compare our current calculations of the s-process nucleosynthesis nuclei with previous data sets and discuss the differences between them and the implications for nuclear astrophysics.

Preparation of nuclear fuel spheres by flotation-internal gelation

DOEpatents

Haas, Paul A.; Fowler, Victor L.; Lloyd, Milton H.

1987-01-01

A simplified internal gelation process for the preparation of gel spheres of nuclear fuels. The process utilizes perchloroethylene as a gelation medium. Gelation is accomplished by directing droplets of a nuclear fuel broth into a moving volume of hot perchloroethylene (about 85.degree. C.) in a trough. Gelation takes place as the droplets float on the surface of the perchloroethylene and the resultant gel spheres are carried directly into an ager column which is attached to the trough. The aged spheres are disengaged from the perchloroethylene on a moving screen and are deposited in an aqueous wash column.

Interviewing a Silent (Radioactive) Witness through Nuclear Forensic Analysis.

PubMed

Mayer, Klaus; Wallenius, Maria; Varga, Zsolt

2015-12-01

Nuclear forensics is a relatively young discipline in science which aims at providing information on nuclear material of unknown origin. The determination of characteristic parameters through tailored analytical techniques enables establishing linkages to the material's processing history and hence provides hints on its place and date of production and on the intended use.

Decommissioning: Nuclear Power's Missing Link. Worldwatch Paper 69.

ERIC Educational Resources Information Center

Pollock, Cynthia

The processes and associated dilemmas of nuclear power plant decommissioning are reviewed in this publication. Decommissioning involves the clearing up and disposal of a retired nuclear plant and its equipment of such a way as to safeguard the public from the dangers of radioactivity. Related problem areas are identified and include: (1) closure…

Drosophila histone locus bodies form by hierarchical recruitment of components

PubMed Central

White, Anne E.; Burch, Brandon D.; Yang, Xiao-cui; Gasdaska, Pamela Y.; Dominski, Zbigniew; Marzluff, William F.

2011-01-01

Nuclear bodies are protein- and RNA-containing structures that participate in a wide range of processes critical to genome function. Molecular self-organization is thought to drive nuclear body formation, but whether this occurs stochastically or via an ordered, hierarchical process is not fully understood. We addressed this question using RNAi and proteomic approaches in Drosophila melanogaster to identify and characterize novel components of the histone locus body (HLB), a nuclear body involved in the expression of replication-dependent histone genes. We identified the transcription elongation factor suppressor of Ty 6 (Spt6) and a homologue of mammalian nuclear protein of the ataxia telangiectasia–mutated locus that is encoded by the homeotic gene multisex combs (mxc) as novel HLB components. By combining genetic manipulation in both cell culture and embryos with cytological observations of Mxc, Spt6, and the known HLB components, FLICE-associated huge protein, Mute, U7 small nuclear ribonucleoprotein, and MPM-2 phosphoepitope, we demonstrated sequential recruitment and hierarchical dependency for localization of factors to HLBs during development, suggesting that ordered assembly can play a role in nuclear body formation. PMID:21576393

Identification of karyopherins involved in the nuclear import of RNA exosome subunit Rrp6 in Saccharomyces cerevisiae.

PubMed

Gonzales-Zubiate, Fernando A; Okuda, Ellen K; Da Cunha, Julia P C; Oliveira, Carla Columbano

2017-07-21

The exosome is a conserved multiprotein complex essential for RNA processing and degradation. The nuclear exosome is a key factor for pre-rRNA processing through the activity of its catalytic subunits, Rrp6 and Rrp44. In Saccharomyces cerevisiae , Rrp6 is exclusively nuclear and has been shown to interact with exosome cofactors. With the aim of analyzing proteins associated with the nuclear exosome, in this work, we purified the complex with Rrp6-TAP, identified the co-purified proteins by mass spectrometry, and found karyopherins to be one of the major groups of proteins enriched in the samples. By investigating the biological importance of these protein interactions, we identified Srp1, Kap95, and Sxm1 as the most important karyopherins for Rrp6 nuclear import and the nuclear localization signals recognized by them. Based on the results shown here, we propose a model of multiple pathways for the transport of Rrp6 to the nucleus. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

Strategies for investigating nuclear-cytoplasmic tRNA dynamics in yeast and mammalian cells.

PubMed

Pierce, Jacqueline B; Chafe, Shawn C; Eswara, Manoja B K; van der Merwe, George; Mangroo, Dev

2014-01-01

Nuclear-cytoplasmic tRNA transport involves multiple pathways that are segregated by the involvement of distinct proteins. The tRNA export process begins in the nucleolus, where the functionality of newly produced tRNAs are tested by aminoacylation, and ends with the delivery of the exported aminoacyl tRNAs to the eukaryotic elongation factor eEF-1A for utilization in protein synthesis in the cytoplasm. Recent studies have identified a number of proteins that participate in nuclear tRNA export in both yeast and mammals. However, genetic and biochemical evidence suggest that additional components, which have yet to be identified, also participate in nuclear-cytoplasmic tRNA trafficking. Here we review key strategies that have led to the identification and characterization of proteins that are involved in the nuclear tRNA export process in yeasts and mammals. The approaches described will greatly facilitate the identification and delineation of the roles of new proteins involved in nuclear export of tRNAs to the cytoplasm. Copyright © 2014 Elsevier Inc. All rights reserved.

Mechanisms of nuclear pore complex assembly - two different ways of building one molecular machine.

PubMed

Otsuka, Shotaro; Ellenberg, Jan

2018-02-01

The nuclear pore complex (NPC) mediates all macromolecular transport across the nuclear envelope. In higher eukaryotes that have an open mitosis, NPCs assemble at two points in the cell cycle: during nuclear assembly in late mitosis and during nuclear growth in interphase. How the NPC, the largest nonpolymeric protein complex in eukaryotic cells, self-assembles inside cells remained unclear. Recent studies have started to uncover the assembly process, and evidence has been accumulating that postmitotic and interphase NPC assembly use fundamentally different mechanisms; the duration, structural intermediates, and regulation by molecular players are different and different types of membrane deformation are involved. In this Review, we summarize the current understanding of these two modes of NPC assembly and discuss the structural and regulatory steps that might drive the assembly processes. We furthermore integrate understanding of NPC assembly with the mechanisms for rapid nuclear growth in embryos and, finally, speculate on the evolutionary origin of the NPC implied by the presence of two distinct assembly mechanisms. © 2017 The Authors. FEBS Letters published by John Wiley & Sons Ltd on behalf of Federation of European Biochemical Societies.

Nuclear physics: quantitative single-cell approaches to nuclear organization and gene expression.

PubMed

Lionnet, T; Wu, B; Grünwald, D; Singer, R H; Larson, D R

2010-01-01

The internal workings of the nucleus remain a mystery. A list of component parts exists, and in many cases their functional roles are known for events such as transcription, RNA processing, or nuclear export. Some of these components exhibit structural features in the nucleus, regions of concentration or bodies that have given rise to the concept of functional compartmentalization--that there are underlying organizational principles to be described. In contrast, a picture is emerging in which transcription appears to drive the assembly of the functional components required for gene expression, drawing from pools of excess factors. Unifying this seemingly dual nature requires a more rigorous approach, one in which components are tracked in time and space and correlated with onset of specific nuclear functions. In this chapter, we anticipate tools that will address these questions and provide the missing kinetics of nuclear function. These tools are based on analyzing the fluctuations inherent in the weak signals of endogenous nuclear processes and determining values for them. In this way, it will be possible eventually to provide a computational model describing the functional relationships of essential components.

Off-Gas Treatment: Evaluation of Nano-structured Sorbents for Selective Removal of Contaminants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Utgikar, Vivek; Aston, D. Eric; Sabharwall, Piyush

Nuclear energy has practically unlimited potential to satisfy world’s energy needs for the foreseeable future. However, a comprehensive and reliable solution must be devised to address the key issues related to nuclear waste management in order to develop nuclear energy in a safe and responsible manner. Capture and immobilization of volatile radionuclides from nuclear operations is an essential component of an integrated nuclear waste management system. The majority of emissions occur during the treatment of the used nuclear fuel (UNF) as it is chopped and dissolved in the boiling nitric acid for subsequent extraction steps. The radionuclides contained in themore » off-gas include 129I, 85Kr, tritium (3H) and 14C. Several alternative technologies have been investigated, with effective adsorption based processes holding the most potential for controlling these emissions, which is highly desirable for the development of the advanced fuel cycle. Proposed project is aimed at developing using a nanosorbent-based process for the capture and immobilization of the radionuclides of interest.« less

Lamina-independent lamins in the nuclear interior serve important functions.

PubMed

Dechat, T; Gesson, K; Foisner, R

2010-01-01

Nuclear lamins were originally described as the main constituents of the nuclear lamina, a filamentous meshwork closely associated with the inner nuclear membrane. However, within recent years, it has become increasingly evident that a fraction of lamins also resides throughout the nuclear interior. As intermediate-filament-type proteins, lamins have been suggested to fulfill mainly structural functions such as providing shape and mechanical stability to the nucleus. But recent findings show that both peripheral and nucleoplasmic lamins also have important roles in essential cellular processes such as transcription, DNA replication, cell cycle progression, and chromatin organization. Furthermore, more than 300 mutations in the gene encoding A-type lamins have been associated with several human diseases now generally termed laminopathies and comprising muscular dystrophies, lipodystrophies, cardiomyopathies, and premature aging diseases. This review focuses on the lamina-independent pool of lamins in the nuclear interior, which surprisingly has not been studied in much detail so far. We discuss the properties and regulation of nucleoplasmic lamins during the cell cycle, their interaction partners, and their potential involvement in cellular processes and the development of laminopathies.

Pyroprocessing of Fast Flux Test Facility Nuclear Fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

B.R. Westphal; G.L. Fredrickson; G.G. Galbreth

Used nuclear fuel from the Fast Flux Test Facility (FFTF) was recently transferred to the Idaho National Laboratory and processed by pyroprocessing in the Fuel Conditioning Facility. Approximately 213 kg of uranium from sodium-bonded metallic FFTF fuel was processed over a one year period with the equipment previously used for the processing of EBR-II used fuel. The peak burnup of the FFTF fuel ranged from 10 to 15 atom% for the 900+ chopped elements processed. Fifteen low-enriched uranium ingots were cast following the electrorefining and distillation operations to recover approximately 192 kg of uranium. A material balance on the primarymore » fuel constituents, uranium and zirconium, during the FFTF campaign will be presented along with a brief description of operating parameters. Recoverable uranium during the pyroprocessing of FFTF nuclear fuel was greater than 95% while the purity of the final electrorefined uranium products exceeded 99%.« less

Pyroprocessing of fast flux test facility nuclear fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Westphal, B.R.; Wurth, L.A.; Fredrickson, G.L.

Used nuclear fuel from the Fast Flux Test Facility (FFTF) was recently transferred to the Idaho National Laboratory and processed by pyroprocessing in the Fuel Conditioning Facility. Approximately 213 kg of uranium from sodium-bonded metallic FFTF fuel was processed over a one year period with the equipment previously used for the processing of EBR-II used fuel. The peak burnup of the FFTF fuel ranged from 10 to 15 atom% for the 900+ chopped elements processed. Fifteen low-enriched uranium ingots were cast following the electrorefining and distillation operations to recover approximately 192 kg of uranium. A material balance on the primarymore » fuel constituents, uranium and zirconium, during the FFTF campaign will be presented along with a brief description of operating parameters. Recoverable uranium during the pyroprocessing of FFTF nuclear fuel was greater than 95% while the purity of the final electro-refined uranium products exceeded 99%. (authors)« less

Graphical Environment Tools for Application to Gamma-Ray Energy Tracking Arrays

DOE Office of Scientific and Technical Information (OSTI.GOV)

Todd, Richard A.; Radford, David C.

2013-12-30

Highly segmented, position-sensitive germanium detector systems are being developed for nuclear physics research where traditional electronic signal processing with mixed analog and digital function blocks would be enormously complex and costly. Future systems will be constructed using pipelined processing of high-speed digitized signals as is done in the telecommunications industry. Techniques which provide rapid algorithm and system development for future systems are desirable. This project has used digital signal processing concepts and existing graphical system design tools to develop a set of re-usable modular functions and libraries targeted for the nuclear physics community. Researchers working with complex nuclear detector arraysmore » such as the Gamma-Ray Energy Tracking Array (GRETA) have been able to construct advanced data processing algorithms for implementation in field programmable gate arrays (FPGAs) through application of these library functions using intuitive graphical interfaces.« less

Nucleosynthesis in the early Galaxy: Progress and challenges.

NASA Astrophysics Data System (ADS)

Montes, Fernando

2015-10-01

Chemical imprints left by the first stars in the oldest stars of the Milky Way gives clues of the stellar nucleosynthesis responsible for the creation of elements heavier than iron. Recent progress in astronomical observations and in the modeling of the chemical evolution of the Galaxy have shown that multiple nucleosynthesis processes may operate at those early times. In this talk I will review some of that evidence along with the important role that nuclear reactions play in those processes. I will focus in progress in our understanding of the rapid neutron capture process (r-process) and in new results on nucleosynthesis in core-collapse supernovae and neutrino-driven winds that produce elements up to silver. I will show some examples of recent nuclear physics measurements addressing the need for better nuclear data and give an outlook of the remaining challenges and future plans to continue those measurements.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nation, J.E.

Whether and by what means nations can successfully de-escalate nuclear crises - and avoid the disastrous effects of nuclear war - will remain two of the most critical challenges facing humankind. Whatever the future of superpower relations, the United States, the Soviet Union, and other nations will undoubtedly continue to possess and to threaten the use of nuclear weapons. Moreover, the number of nations with nuclear weapons seems likely to increase. This examines how nations in crises might successfully move back from the brink of nuclear war - and how confidence-building measures might help and hinder the de-escalatory process.

Nuclear emergency management procedures in Europe

NASA Astrophysics Data System (ADS)

Carter, Emma

The Chernobyl accident brought to the fore the need for decision-making in nuclear emergency management to be transparent and consistent across Europe. A range of systems to support decision-making in future emergencies have since been developed, but, by and large, with little consultation with potential decision makers and limited understanding of the emergency management procedures across Europe and how they differ. In nuclear emergency management, coordination, communication and information sharing are of paramount importance. There are many key players with their own technical expertise, and several key activities occur in parallel, across different locations. Business process modelling can facilitate understanding through the representation of processes, aid transparency and structure the analysis, comparison and improvement of processes. This work has been conducted as part of a European Fifth Framework Programme project EVATECH, whose aim was to improve decision support methods, models and processes taking into account stakeholder expectations and concerns. It has involved the application of process modelling to document and compare the emergency management processes in four European countries. It has also involved a multidisciplinary approach taking a socio-technical perspective. The use of process modelling did indeed facilitate understanding and provided a common platform, which was not previously available, to consider emergency management processes. This thesis illustrates the structured analysis approach that process modelling enables. Firstly, through an individual analysis for the United Kingdom (UK) model that illustrated the potential benefits for a country. These are for training purposes, to build reflexive shared mental models, to aid coordination and for process improvement. Secondly, through a comparison of the processes in Belgium, Germany, Slovak Republic and the UK. In this comparison of the four processes we observed that the four process models are substantially different in their organisational structure and identified differences in the management of advice, where decisions are made and the communication network style. Another key aspect of this work is that through the structured analysis conducted we were able to develop a framework for the evaluation of DSS from the perspective of process. This work concludes reflecting on the challenges, which the European off-site nuclear emergency community face and suggest direction for future work, with particular reference to a recent conference on the capabilities and challenges of offsite nuclear emergency management, the Salzburg Symposium 2003.

A new methodology for estimating nuclear casualties as a function of time.

PubMed

Zirkle, Robert A; Walsh, Terri J; Disraelly, Deena S; Curling, Carl A

2011-09-01

The Human Response Injury Profile (HRIP) nuclear methodology provides an estimate of casualties occurring as a consequence of nuclear attacks against military targets for planning purposes. The approach develops user-defined, time-based casualty and fatality estimates based on progressions of underlying symptoms and their severity changes over time. This paper provides a description of the HRIP nuclear methodology and its development, including inputs, human response and the casualty estimation process.

Zero Nuclear Weapons and Nuclear Security Enterprise Modernization

DTIC Science & Technology

2011-01-01

national security strategy. For the first time since the Manhattan Project , the United States was no longer building nuclear weapons and was in fact...50 to 60 years to the Manhattan Project and are on the verge of catastrophic failure. Caustic chemicals and processes have sped up the corrosion and...day, the United States must fund the long-term modernization effort of the entire enter­ prise. Notes 1. Nuclear Weapon Archive, “The Manhattan

Leveraging success: applying Interagency Lessons learned to the Joint Air Delivered Nuclear Weapons Acquisition Process

DTIC Science & Technology

Effective coordination and communication between the Department of Energy (DOE) and the Department of Defense (DoD) is necessary to ensure that the... nuclear weapons stockpile remains safe, secure, and effective without nuclear testing. The science-based Stockpile Sustainment Program (SSP) is the...method used to sustain and maintain the nuclear stockpile throughout the weapons life cycle. A comprehensive review was conducted of the joint

Control of nuclear β-dystroglycan content is crucial for the maintenance of nuclear envelope integrity and function.

PubMed

Vélez-Aguilera, Griselda; de Dios Gómez-López, Juan; Jiménez-Gutiérrez, Guadalupe E; Vásquez-Limeta, Alejandra; Laredo-Cisneros, Marco S; Gómez, Pablo; Winder, Steve J; Cisneros, Bulmaro

2018-02-01

β-Dystroglycan (β-DG) is a plasma membrane protein that has ability to target to the nuclear envelope (NE) to maintain nuclear architecture. Nevertheless, mechanisms controlling β-DG nuclear localization and the physiological consequences of a failure of trafficking are largely unknown. We show that β-DG has a nuclear export pathway in myoblasts that depends on the recognition of a nuclear export signal located in its transmembrane domain, by CRM1. Remarkably, NES mutations forced β-DG nuclear accumulation resulting in mislocalization and decreased levels of emerin and lamin B1 and disruption of various nuclear processes in which emerin (centrosome-nucleus linkage and β-catenin transcriptional activity) and lamin B1 (cell cycle progression and nucleoli structure) are critically involved. In addition to nuclear export, the lifespan of nuclear β-DG is restricted by its nuclear proteasomal degradation. Collectively our data show that control of nuclear β-DG content by the combination of CRM1 nuclear export and nuclear proteasome pathways is physiologically relevant to preserve proper NE structure and activity. Copyright © 2017 Elsevier B.V. All rights reserved.

Desalting and Nuclear Energy

ERIC Educational Resources Information Center

Burwell, Calvin C.

1971-01-01

Future use of nuclear energy to produce electricity and desalted water is outlined. Possible desalting processes are analyzed to show economic feasibility and the place in planning in world's economic growth. (DS)

Measurement of the intensity ratio of Auger and conversion electrons for the electron capture decay of 125I.

PubMed

Alotiby, M; Greguric, I; Kibédi, T; Lee, B Q; Roberts, M; Stuchbery, A E; Tee, Pi; Tornyi, T; Vos, M

2018-03-21

Auger electrons emitted after nuclear decay have potential application in targeted cancer therapy. For this purpose it is important to know the Auger electron yield per nuclear decay. In this work we describe a measurement of the ratio of the number of conversion electrons (emitted as part of the nuclear decay process) to the number of Auger electrons (emitted as part of the atomic relaxation process after the nuclear decay) for the case of 125 I. Results are compared with Monte-Carlo type simulations of the relaxation cascade using the BrIccEmis code. Our results indicate that for 125 I the calculations based on rates from the Evaluated Atomic Data Library underestimate the K Auger yields by 20%.

Robotics for Nuclear Material Handling at LANL:Capabilities and Needs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Harden, Troy A; Lloyd, Jane A; Turner, Cameron J

Nuclear material processing operations present numerous challenges for effective automation. Confined spaces, hazardous materials and processes, particulate contamination, radiation sources, and corrosive chemical operations are but a few of the significant hazards. However, automated systems represent a significant safety advance when deployed in place of manual tasks performed by human workers. The replacement of manual operations with automated systems has been desirable for nearly 40 years, yet only recently are automated systems becoming increasingly common for nuclear materials handling applications. This paper reviews several automation systems which are deployed or about to be deployed at Los Alamos National Laboratory formore » nuclear material handling operations. Highlighted are the current social and technological challenges faced in deploying automated systems into hazardous material handling environments and the opportunities for future innovations.« less

Measurement of the intensity ratio of Auger and conversion electrons for the electron capture decay of 125I

NASA Astrophysics Data System (ADS)

Alotiby, M.; Greguric, I.; Kibédi, T.; Lee, B. Q.; Roberts, M.; Stuchbery, A. E.; Tee, Pi; Tornyi, T.; Vos, M.

2018-03-01

Auger electrons emitted after nuclear decay have potential application in targeted cancer therapy. For this purpose it is important to know the Auger electron yield per nuclear decay. In this work we describe a measurement of the ratio of the number of conversion electrons (emitted as part of the nuclear decay process) to the number of Auger electrons (emitted as part of the atomic relaxation process after the nuclear decay) for the case of 125I. Results are compared with Monte-Carlo type simulations of the relaxation cascade using the BrIccEmis code. Our results indicate that for 125I the calculations based on rates from the Evaluated Atomic Data Library underestimate the K Auger yields by 20%.

Calculations of Maxwellian-averaged cross sections and astrophysical reaction rates using the ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, and ENDF/B-VI.8 evaluated nuclear reaction data libraries

NASA Astrophysics Data System (ADS)

Pritychenko, B.; Mughaghab, S. F.; Sonzogni, A. A.

2010-11-01

We have calculated the Maxwellian-averaged cross sections and astrophysical reaction rates of the stellar nucleosynthesis reactions (n, γ), (n, fission), (n, p), (n, α), and (n, 2n) using the ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, and ENDF/B-VI.8 evaluated nuclear reaction data libraries. These four major nuclear reaction libraries were processed under the same conditions for Maxwellian temperatures (kT) ranging from 1 keV to 1 MeV. We compare our current calculations of the s-process nucleosynthesis nuclei with previous data sets and discuss the differences between them and the implications for nuclear astrophysics.

Medical Image Processing Server applied to Quality Control of Nuclear Medicine.

NASA Astrophysics Data System (ADS)

Vergara, C.; Graffigna, J. P.; Marino, E.; Omati, S.; Holleywell, P.

2016-04-01

This paper is framed within the area of medical image processing and aims to present the process of installation, configuration and implementation of a processing server of medical images (MIPS) in the Fundación Escuela de Medicina Nuclear located in Mendoza, Argentina (FUESMEN). It has been developed in the Gabinete de Tecnologia Médica (GA.TE.ME), Facultad de Ingeniería-Universidad Nacional de San Juan. MIPS is a software that using the DICOM standard, can receive medical imaging studies of different modalities or viewing stations, then it executes algorithms and finally returns the results to other devices. To achieve the objectives previously mentioned, preliminary tests were conducted in the laboratory. More over, tools were remotely installed in clinical enviroment. The appropiate protocols for setting up and using them in different services were established once defined those suitable algorithms. Finally, it’s important to focus on the implementation and training that is provided in FUESMEN, using nuclear medicine quality control processes. Results on implementation are exposed in this work.

Improvement of nuclear power plants within the perspective of applications of lean manufacturing practices

NASA Astrophysics Data System (ADS)

Malek, A. K.; Muhammad, H. I.; Rosmaini, A.; Alaa, A. S.; Falah, A. M.

2017-09-01

Development and improvement process are essential to the companies and factories of various kinds and this necessity is related aspects of cost, time and risk that can be avoided, these aspects are available at the nuclear power stations essential demands cannot be ignored. The lean management technique is one of the recent trends in the management system. Where the lean management is stated as the system increases the customer value and reduces the wastage process in an industry or in a power plants. Therefore, there is an urgent necessity to ensure the development and improvement in nuclear power plants in the pre-established in process of being established and stage of the management and production. All of these stages according to the study are closely related to the necessity operationalize and apply lean manufacturing practices that these applications are ineffective and clear contribution to reduce costs and control of production processes and the process of reducing future risks that could be exposed to the station.

Active Interrogation using Photofission Technique for Nuclear Materials Control and Accountability

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yang, Haori

2016-03-31

Innovative systems with increased sensitivity and resolution are in great demand to detect diversion and to prevent misuse in support of nuclear materials management for the U.S. fuel cycle. Nuclear fission is the most important multiplicative process involved in non-destructive active interrogation. This process produces the most easily recognizable signature for nuclear materials. In addition to thermal or high-energy neutrons, high-energy gamma rays can also excite a nucleus and cause fission through a process known as photofission. Electron linear accelerators (linacs) are widely used as the interrogating photon sources for inspection methods involving photofission technique. After photofission reactions, prompt signalsmore » are much stronger than the delayed signals, but it is difficult to quantify them in practical measurements. Delayed signals are easily distinguishable from the interrogating radiation. Linac-based, advanced inspection techniques utilizing the delayed signals after photofission have been extensively studied for homeland security applications. Previous research also showed that a unique delayed gamma ray energy spectrum exists for each fissionable isotope. In this work, high-energy delayed γ-rays were demonstrated to be signatures for detection, identification, and quantification of special nuclear materials. Such γ-rays were measured in between linac pulses using independent data acquisition systems. A list-mode system was developed to measure low-energy delayed γ-rays after irradiation. Photofission product yields of 238U and 239Pu were determined based on the measured delayed γ-ray spectra. The differential yields of delayed γ-rays were also proven to be able to discriminate nuclear from non-nuclear materials. The measurement outcomes were compared with Monte Carlo simulation results. It was demonstrated that the current available codes have capabilities and limitations in the simulation of photofission process. A two-fold approach was used to address the high-rate challenge in used nuclear fuel assay based on photofission technique. First, a standard HPGe preamplifier was modified to improve its capabilities in high-rate pulsed photofission environment. Second, advanced pulse processing algorithms were shown to greatly improve throughput rate without large sacrifice in energy resolution at ultra-high input count rate. Two customized gamma spectroscopy systems were also developed in real-time on FPGAs. They were shown to have promising performance matching available commercial units.« less

In medium dispersion relation effects in nuclear inclusive reactions at intermediate and low energies

NASA Astrophysics Data System (ADS)

Nieves, Juan; Sobczyk, Joanna E.

2017-08-01

In a well-established many-body framework, successful in modeling a great variety of nuclear processes, we analyze the role of the spectral functions (SFs) accounting for the modifications of the dispersion relation of nucleons embedded in a nuclear medium. We concentrate in processes mostly governed by one-body mechanisms, and study possible approximations to evaluate the particle-hole propagator using SFs. We also investigate how to include together SFs and long-range RPA-correlation corrections in the evaluation of nuclear response functions, discussing the existing interplay between both type of nuclear effects. At low energy transfers (≤ 50 MeV), we compare our predictions for inclusive muon and radiative pion captures in nuclei, and charge-current (CC) neutrino-nucleus cross sections with experimental results. We also present an analysis of intermediate energy quasi-elastic neutrino scattering for various targets and both neutrino and antineutrino CC driven processes. In all cases, we pay special attention to estimate the uncertainties affecting the theoretical predictions. In particular, we show that errors on the σμ /σe ratio are much smaller than 5%, and also much smaller than the size of the SF+RPA nuclear corrections, which produce significant effects, not only in the individual cross sections, but also in their ratio for neutrino energies below 400 MeV. These latter nuclear corrections, beyond Pauli blocking, turn out to be thus essential to achieve a correct theoretical understanding of this ratio of cross sections of interest for appearance neutrino oscillation experiments. We also briefly compare our SF and RPA results to predictions obtained within other representative approaches.

Development of utility generic functional requirements for electronic work packages and computer-based procedures

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oxstrand, Johanna

The Nuclear Electronic Work Packages - Enterprise Requirements (NEWPER) initiative is a step toward a vision of implementing an eWP framework that includes many types of eWPs. This will enable immediate paper-related cost savings in work management and provide a path to future labor efficiency gains through enhanced integration and process improvement in support of the Nuclear Promise (Nuclear Energy Institute 2016). The NEWPER initiative was organized by the Nuclear Information Technology Strategic Leadership (NITSL) group, which is an organization that brings together leaders from the nuclear utility industry and regulatory agencies to address issues involved with information technology usedmore » in nuclear-power utilities. NITSL strives to maintain awareness of industry information technology-related initiatives and events and communicates those events to its membership. NITSL and LWRS Program researchers have been coordinating activities, including joint organization of NEWPER-related meetings and report development. The main goal of the NEWPER initiative was to develop a set of utility generic functional requirements for eWP systems. This set of requirements will support each utility in their process of identifying plant-specific functional and non-functional requirements. The NEWPER initiative has 140 members where the largest group of members consists of 19 commercial U.S. nuclear utilities and eleven of the most prominent vendors of eWP solutions. Through the NEWPER initiative two sets of functional requirements were developed; functional requirements for electronic work packages and functional requirements for computer-based procedures. This paper will describe the development process as well as a summary of the requirements.« less

Protoparvovirus Knocking at the Nuclear Door.

PubMed

Mäntylä, Elina; Kann, Michael; Vihinen-Ranta, Maija

2017-10-02

Protoparvoviruses target the nucleus due to their dependence on the cellular reproduction machinery during the replication and expression of their single-stranded DNA genome. In recent years, our understanding of the multistep process of the capsid nuclear import has improved, and led to the discovery of unique viral nuclear entry strategies. Preceded by endosomal transport, endosomal escape and microtubule-mediated movement to the vicinity of the nuclear envelope, the protoparvoviruses interact with the nuclear pore complexes. The capsids are transported actively across the nuclear pore complexes using nuclear import receptors. The nuclear import is sometimes accompanied by structural changes in the nuclear envelope, and is completed by intranuclear disassembly of capsids and chromatinization of the viral genome. This review discusses the nuclear import strategies of protoparvoviruses and describes its dynamics comprising active and passive movement, and directed and diffusive motion of capsids in the molecularly crowded environment of the cell.

Cloud physics laboratory project science and applications working group

NASA Technical Reports Server (NTRS)

Hung, R. J.

1977-01-01

The conditions of the expansion chamber under zero gravity environment were simulated. The following three branches of fluid mechanics simulation under low gravity environment were accomplished: (1) oscillation of the water droplet which characterizes the nuclear oscillation in nuclear physics, bubble oscillation of two phase flow in chemical engineering, and water drop oscillation in meteorology; (2) rotation of the droplet which characterizes nuclear fission in nuclear physics, formation of binary stars and rotating stars in astrophysics, and breakup of the water droplet in meteorology; and (3) collision and coalescence of the water droplets which characterizes nuclear fusion in nuclear physics and processes of rain formation in meteorology.

METHOD FOR PURIFYING URANIUM

DOEpatents

Knighton, J.B.; Feder, H.M.

1960-04-26

A process is given for purifying a uranium-base nuclear material. The nuclear material is dissolved in zinc or a zinc-magnesium alloy and the concentration of magnesium is increased until uranium precipitates.

Production of the entire range of r-process nuclides by black hole accretion disc outflows from neutron star mergers

NASA Astrophysics Data System (ADS)

Wu, Meng-Ru; Fernández, Rodrigo; Martínez-Pinedo, Gabriel; Metzger, Brian D.

2016-12-01

We consider r-process nucleosynthesis in outflows from black hole accretion discs formed in double neutron star and neutron star-black hole mergers. These outflows, powered by angular momentum transport processes and nuclear recombination, represent an important - and in some cases dominant - contribution to the total mass ejected by the merger. Here we calculate the nucleosynthesis yields from disc outflows using thermodynamic trajectories from hydrodynamic simulations, coupled to a nuclear reaction network. We find that outflows produce a robust abundance pattern around the second r-process peak (mass number A ˜ 130), independent of model parameters, with significant production of A < 130 nuclei. This implies that dynamical ejecta with high electron fraction may not be required to explain the observed abundances of r-process elements in metal poor stars. Disc outflows reach the third peak (A ˜ 195) in most of our simulations, although the amounts produced depend sensitively on the disc viscosity, initial mass or entropy of the torus, and nuclear physics inputs. Some of our models produce an abundance spike at A = 132 that is absent in the Solar system r-process distribution. The spike arises from convection in the disc and depends on the treatment of nuclear heating in the simulations. We conclude that disc outflows provide an important - and perhaps dominant - contribution to the r-process yields of compact binary mergers, and hence must be included when assessing the contribution of these systems to the inventory of r-process elements in the Galaxy.

REVIEW OF MECHANISTIC UNDERSTANDING AND MODELING AND UNCERTAINTY ANALYSIS METHODS FOR PREDICTING CEMENTITIOUS BARRIER PERFORMANCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Langton, C.; Kosson, D.

2009-11-30

Cementitious barriers for nuclear applications are one of the primary controls for preventing or limiting radionuclide release into the environment. At the present time, performance and risk assessments do not fully incorporate the effectiveness of engineered barriers because the processes that influence performance are coupled and complicated. Better understanding the behavior of cementitious barriers is necessary to evaluate and improve the design of materials and structures used for radioactive waste containment, life extension of current nuclear facilities, and design of future nuclear facilities, including those needed for nuclear fuel storage and processing, nuclear power production and waste management. The focusmore » of the Cementitious Barriers Partnership (CBP) literature review is to document the current level of knowledge with respect to: (1) mechanisms and processes that directly influence the performance of cementitious materials (2) methodologies for modeling the performance of these mechanisms and processes and (3) approaches to addressing and quantifying uncertainties associated with performance predictions. This will serve as an important reference document for the professional community responsible for the design and performance assessment of cementitious materials in nuclear applications. This review also provides a multi-disciplinary foundation for identification, research, development and demonstration of improvements in conceptual understanding, measurements and performance modeling that would be lead to significant reductions in the uncertainties and improved confidence in the estimating the long-term performance of cementitious materials in nuclear applications. This report identifies: (1) technology gaps that may be filled by the CBP project and also (2) information and computational methods that are in currently being applied in related fields but have not yet been incorporated into performance assessments of cementitious barriers. The various chapters contain both a description of the mechanism or and a discussion of the current approaches to modeling the phenomena.« less

Cluster formation in nuclear reactions from mean-field inhomogeneities

NASA Astrophysics Data System (ADS)

Napolitani, Paolo; Colonna, Maria; Mancini-Terracciano, Carlo

2018-05-01

Perturbing fluids of neutrons and protons (nuclear matter) may lead, as the most catastrophic effect, to the rearrangement of the fluid into clusters of nucleons. A similar process may occur in a single atomic nucleus undergoing a violent perturbation, like in heavy-ion collisions tracked in particle accelerators at around 30 to 50 MeV per nucleon: in this conditions, after the initial collision shock, the nucleus expands and then clusterises into several smaller nuclear fragments. Microscopically, when violent perturbation are applied to nuclear matter, a process of clusterisation arises from the combination of several fluctuation modes of large-amplitude where neutrons and protons may oscillate in phase or out of phase. The imposed perturbation leads to conditions of instability, the wavelengths which are the most amplified have sizes comparable to small atomic nuclei. We found that these conditions, explored in heavy-ion collisions, correspond to the splitting of a nucleus into fragments ranging from Oxygen to Neon in a time interval shorter than one zeptosecond (10 ‑ 21s). From the out-of-phase oscillations of neutrons and protons another property arises, the smaller fragments belonging to a more volatile phase get more neutron enriched: in the heavy-ion collision case this process, called distillation, reflects in the isotopic distributions of the fragments. The resulting dynamical description of heavy-ion collisions is an improvement with respect to more usual statistical approaches, based on the equilibrium assumption. It allows in fact to characterise also the very fast early stages of the collision process which are out of equilibrium. Such dynamical description is the core of the Boltzmann-Langevin One Body (BLOB) model, which in its latest development unifies in a common approach the description of fluctuations in nuclear matter, and a predictive description of the disintegration of nuclei into nuclear fragments. After a theoretical introduction, a few practical examples will be illustrated. This paper resumes the extended analysis of fluctuations in nuclear matter of ref. [2] and briefly reviews applications to heavy-ion collisions.

Processing and analysis of commercial satellite image data of the nuclear accident near Chernobyl, U. S. S. R

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sadowski, F.G.; Covington, S.J.

1987-01-01

Advanced digital processing techniques were applied to Landsat-5 Thematic Mapper (TM) data and SPOT high-resolution visible (HRV) panchromatic data to maximize the utility of images of a nuclear power plant emergency at Chernobyl in the Soviet Ukraine. The results of the data processing and analysis illustrate the spectral and spatial capabilities of the two sensor systems and provide information about the severity and duration of the events occurring at the power plant site.

Reversible Nuclear-Lipid-Droplet Morphology Induced by Oleic Acid: A Link to Cellular-Lipid Metabolism

PubMed Central

Lagrutta, Lucía C.; Montero-Villegas, Sandra; Layerenza, Juan P.; Sisti, Martín S.; García de Bravo, Margarita M.

2017-01-01

Neutral lipids—involved in many cellular processes—are stored as lipid droplets (LD), those mainly cytosolic (cLD) along with a small nuclear population (nLD). nLD could be involved in nuclear-lipid homeostasis serving as an endonuclear buffering system that would provide or incorporate lipids and proteins involved in signalling pathways as transcription factors and as enzymes of lipid metabolism and nuclear processes. Our aim was to determine if nLD constituted a dynamic domain. Oleic-acid (OA) added to rat hepatocytes or HepG2 cells in culture produced cellular-phenotypic LD modifications: increases in TAG, CE, C, and PL content and in cLD and nLD numbers and sizes. LD increments were reversed on exclusion of OA and were prevented by inhibition of acyl-CoA synthetase (with Triacsin C) and thus lipid biosynthesis. Under all conditions, nLD corresponded to a small population (2–10%) of total cellular LD. The anabolism triggered by OA, involving morphologic and size changes within the cLD and nLD populations, was reversed by a net balance of catabolism, upon eliminating OA. These catabolic processes included lipolysis and the mobilization of hydrolyzed FA from the LD to cytosolic-oxidation sites. These results would imply that nLD are actively involved in nuclear processes that include lipids. In conclusion, nLD are a dynamic nuclear domain since they are modified by OA through a reversible mechanism in combination with cLD; this process involves acyl-CoA-synthetase activity; ongoing TAG, CE, and PL biosynthesis. Thus, liver nLD and cLD are both dynamic cellular organelles. PMID:28125673

Feasibility of clinical detection of cervical dysplasia using angle-resolved low coherence interferometry measurements of depth-resolved nuclear morphology.

PubMed

Ho, Derek; Drake, Tyler K; Smith-McCune, Karen K; Darragh, Teresa M; Hwang, Loris Y; Wax, Adam

2017-03-15

This study sought to establish the feasibility of using in situ depth-resolved nuclear morphology measurements for detection of cervical dysplasia. Forty enrolled patients received routine cervical colposcopy with angle-resolved low coherence interferometry (a/LCI) measurements of nuclear morphology. a/LCI scans from 63 tissue sites were compared to histopathological analysis of co-registered biopsy specimens which were classified as benign, low-grade squamous intraepithelial lesion (LSIL), or high-grade squamous intraepithelial lesion (HSIL). Results were dichotomized as dysplastic (LSIL/HSIL) versus non-dysplastic and HSIL versus LSIL/benign to determine both accuracy and potential clinical utility of a/LCI nuclear morphology measurements. Analysis of a/LCI data was conducted using both traditional Mie theory based processing and a new hybrid algorithm that provides improved processing speed to ascertain the feasibility of real-time measurements. Analysis of depth-resolved nuclear morphology data revealed a/LCI was able to detect a significant increase in the nuclear diameter at the depth bin containing the basal layer of the epithelium for dysplastic versus non-dysplastic and HSIL versus LSIL/Benign biopsy sites (both p < 0.001). Both processing techniques resulted in high sensitivity and specificity (>0.80) in identifying dysplastic biopsies and HSIL. The hybrid algorithm demonstrated a threefold decrease in processing time at a slight cost in classification accuracy. The results demonstrate the feasibility of using a/LCI as an adjunctive clinical tool for detecting cervical dysplasia and guiding the identification of optimal biopsy sites. The faster speed from the hybrid algorithm offers a promising approach for real-time clinical analysis. © 2016 UICC.

Feasibility of clinical detection of cervical dysplasia using angle-resolved low coherence interferometry measurements of depth-resolved nuclear morphology

PubMed Central

Ho, Derek; Drake, Tyler K.; Smith-McCune, Karen K.; Darragh, Teresa M.; Hwang, Loris Y.; Wax, Adam

2017-01-01

This study sought to establish the feasibility of using in situ depth-resolved nuclear morphology measurements for detection of cervical dysplasia. Forty (40) enrolled patients received routine cervical colposcopy with angle-resolved low coherence interferometry (a/LCI) measurements of nuclear morphology. a/LCI scans from 63 tissue sites were compared to histopathological analysis of co-registered biopsy specimens which were classified as benign, low-grade squamous intraepithelial lesion (LSIL), or high-grade squamous intraepithelial lesion (HSIL). Results were dichotomized as dysplastic (LSIL/HSIL) versus non-dysplastic and HSIL versus LSIL/benign to determine both accuracy and potential clinical utility of a/LCI nuclear morphology measurements. Analysis of a/LCI data was conducted using both traditional Mie theory based processing and a new hybrid algorithm that provides improved processing speed to ascertain the feasibility of real-time measurements. Analysis of depth-resolved nuclear morphology data revealed a/LCI was able to detect a significant increase in the nuclear diameter at the depth bin containing the basal layer of the epithelium for dysplastic versus non-dysplastic and HSIL versus LSIL/Benign biopsy sites (both p < 0.001). Both processing techniques resulted in high sensitivity and specificity (> 0.80) in identifying dysplastic biopsies and HSIL. The hybrid algorithm demonstrated a threefold decrease in processing time at a slight cost in classification accuracy. The results demonstrate the feasibility of using a/LCI as an adjunctive clinical tool for detecting cervical dysplasia and guiding the identification of optimal biopsy sites. The faster speed from the hybrid algorithm offers a promising approach for real-time clinical analysis. PMID:27883177

The International Safety Framework for nuclear power source applications in outer space-Useful and substantial guidance

NASA Astrophysics Data System (ADS)

Summerer, L.; Wilcox, R. E.; Bechtel, R.; Harbison, S.

2015-06-01

In 2009, the International Safety Framework for Nuclear Power Source Applications in Outer Space was adopted, following a multi-year process that involved all major space faring nations under the auspices of a partnership between the UN Committee on the Peaceful Uses of Outer Space and the International Atomic Energy Agency. The Safety Framework reflects an international consensus on best practices to achieve safety. Following the 1992 UN Principles Relevant to the Use of Nuclear Power Sources in Outer Space, it is the second attempt by the international community to draft guidance promoting the safety of applications of nuclear power sources in space missions. NPS applications in space have unique safety considerations compared with terrestrial applications. Mission launch and outer space operational requirements impose size, mass and other space environment limitations not present for many terrestrial nuclear facilities. Potential accident conditions could expose nuclear power sources to extreme physical conditions. The Safety Framework is structured to provide guidance for both the programmatic and technical aspects of safety. In addition to sections containing specific guidance for governments and for management, it contains technical guidance pertinent to the design, development and all mission phases of space NPS applications. All sections of the Safety Framework contain elements directly relevant to engineers and space mission designers for missions involving space nuclear power sources. The challenge for organisations and engineers involved in the design and development processes of space nuclear power sources and applications is to implement the guidance provided in the Safety Framework by integrating it into the existing standard space mission infrastructure of design, development and operational requirements, practices and processes. This adds complexity to the standard space mission and launch approval processes. The Safety Framework is deliberately generic to remain relevantly independent of technological progress, of national organisational setups and of space mission types. Implementing its guidance therefore leaves room for interpretation and adaptation. Relying on reported practices, we analyse the guidance particularly relevant to engineers and space mission designers.

Nuclear Motility in Glioma Cells Reveals a Cell-Line Dependent Role of Various Cytoskeletal Components

PubMed Central

Kiss, Alexa; Horvath, Peter; Rothballer, Andrea; Kutay, Ulrike; Csucs, Gabor

2014-01-01

Nuclear migration is a general term for the movement of the nucleus towards a specific site in the cell. These movements are involved in a number of fundamental biological processes, such as fertilization, cell division, and embryonic development. Despite of its importance, the mechanism of nuclear migration is still poorly understood in mammalian cells. In order to shed light on the mechanical processes underlying nuclear movements, we adapted a micro-patterning based assay. C6 rat and U87 human glioma cells seeded on fibronectin patterns - thereby forced into a bipolar morphology - displayed oscillatory movements of the nucleus or the whole cell, respectively. We found that both the actomyosin system and microtubules are involved in the nuclear/cellular movements of both cell lines, but their contributions are cell-/migration-type specific. Dynein activity was necessary for nuclear migration of C6 cells but active myosin-II was dispensable. On the other hand, coupled nuclear and cellular movements of U87 cells were driven by actomyosin contraction. We explain these cell-line dependent effects by the intrinsic differences in the overall mechanical tension due to the various cytoskeletal elements inside the cell. Our observations showed that the movements of the nucleus and the centrosome are strongly correlated and display large variation, indicating a tight but flexible coupling between them. The data also indicate that the forces responsible for nuclear movements are not acting directly via the centrosome. Based on our observations, we propose a new model for nuclear oscillations in C6 cells in which dynein and microtubule dynamics are the main drivers of nuclear movements. This mechanism is similar to the meiotic nuclear oscillations of Schizosaccharomyces pombe and may be evolutionary conserved. PMID:24691067

Fundamentals of nuclear medicine

DOE Office of Scientific and Technical Information (OSTI.GOV)

Alazraki, N.P.; Mishkin, F.S.

1988-01-01

The book begins with basic science and statistics relevant to nuclear medicine, and specific organ systems are addressed in separate chapters. A section of the text also covers imaging of groups of disease processes (eg, trauma, cancer). The authors present a comparison between nuclear medicine techniques and other diagnostic imaging studies. A table is given which comments on sensitivities and specificities of common nuclear medicine studies. The sensitivities and specificities are categorized as very high, high, moderate, and so forth.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

This document is a review journal that covers significant developments in the field of nuclear safety. Its scope includes the analysis and control of hazards associated with nuclear energy, operations involving fissionable materials, and the products of nuclear fission and their effects on the environment. Primary emphasis is on safety in reactor design, construction, and operation; however, the safety aspects of the entire fuel cycle, including fuel fabrication, spent-fuel processing, nuclear waste disposal, handling of radioisotopes, and environmental effects of these operations, are also treated.

Dynamic high energy density plasma environments at the National Ignition Facility for nuclear science research

NASA Astrophysics Data System (ADS)

Cerjan, Ch J.; Bernstein, L.; Berzak Hopkins, L.; Bionta, R. M.; Bleuel, D. L.; Caggiano, J. A.; Cassata, W. S.; Brune, C. R.; Frenje, J.; Gatu-Johnson, M.; Gharibyan, N.; Grim, G.; Hagmann, Chr; Hamza, A.; Hatarik, R.; Hartouni, E. P.; Henry, E. A.; Herrmann, H.; Izumi, N.; Kalantar, D. H.; Khater, H. Y.; Kim, Y.; Kritcher, A.; Litvinov, Yu A.; Merrill, F.; Moody, K.; Neumayer, P.; Ratkiewicz, A.; Rinderknecht, H. G.; Sayre, D.; Shaughnessy, D.; Spears, B.; Stoeffl, W.; Tommasini, R.; Yeamans, Ch; Velsko, C.; Wiescher, M.; Couder, M.; Zylstra, A.; Schneider, D.

2018-03-01

The generation of dynamic high energy density plasmas in the pico- to nano-second time domain at high-energy laser facilities affords unprecedented nuclear science research possibilities. At the National Ignition Facility (NIF), the primary goal of inertial confinement fusion research has led to the synergistic development of a unique high brightness neutron source, sophisticated nuclear diagnostic instrumentation, and versatile experimental platforms. These novel experimental capabilities provide a new path to investigate nuclear processes and structural effects in the time, mass and energy density domains relevant to astrophysical phenomena in a unique terrestrial environment. Some immediate applications include neutron capture cross-section evaluation, fission fragment production, and ion energy loss measurement in electron-degenerate plasmas. More generally, the NIF conditions provide a singular environment to investigate the interplay of atomic and nuclear processes such as plasma screening effects upon thermonuclear reactivity. Achieving enhanced understanding of many of these effects will also significantly advance fusion energy research and challenge existing theoretical models.

Fukushima Nuclear Accident: Sticking to the facts, not to the political correctness

NASA Astrophysics Data System (ADS)

Ohska, Tokio

2014-05-01

The Fukushima Nuclear Reactor disaster of 2011 is still a continuing disaster three years later, although some experts have proclaimed the 4 reactors being already under control. It is surely an incredibly difficult task to properly terminate nuclear accidents. However, I should point out that the process of termination plan has been marred by too much of politics and business messing up a scientific approach to do it in a rational way. This blame must to go to both pro-nuclear and anti-nuclear power people. It makes me feel sad to see people not respecting science in executing such a difficult task. I shall list up where things went wrong with the hope that this kind of action, as I do here, would trigger people to get back to science to straighten out the execution process. I will show a few examples of published papers presenting the opinion that it is inappropriate what the Japanese government considers to be safe.

Cellular redistribution of Rad51 in response to DNA damage: novel role for Rad51C.

PubMed

Gildemeister, Otto S; Sage, Jay M; Knight, Kendall L

2009-11-13

Exposure of cells to DNA-damaging agents results in a rapid increase in the formation of subnuclear complexes containing Rad51. To date, it has not been determined to what extent DNA damage-induced cytoplasmic to nuclear transport of Rad51 may contribute to this process. We have analyzed subcellular fractions of HeLa and HCT116 cells and found a significant increase in nuclear Rad51 levels following exposure to a modest dose of ionizing radiation (2 grays). We also observed a DNA damage-induced increase in nuclear Rad51 in the Brca2-defective cell line Capan-1. To address a possible Brca2-independent mechanism for Rad51 nuclear transport, we analyzed subcellular fractions for two other Rad51-interacting proteins, Rad51C and Xrcc3. Rad51C has a functional nuclear localization signal, and although we found that the subcellular distribution of Xrcc3 was not significantly affected by DNA damage, there was a damage-induced increase in nuclear Rad51C. Furthermore, RNA interference-mediated depletion of Rad51C in HeLa and Capan-1 cells resulted in lower steady-state levels of nuclear Rad51 as well as a diminished DNA damage-induced increase. Our results provide important insight into the cellular regulation of Rad51 nuclear entry and a role for Rad51C in this process.

Structural determination of importin alpha in complex with beak and feather disease virus capsid nuclear localization signal

DOE Office of Scientific and Technical Information (OSTI.GOV)

Patterson, Edward I.; EH Graham Centre for Agricultural Innovation; Dombrovski, Andrew K.

2013-09-06

Highlights: •Circovirus capsid proteins contain large nuclear localization signals (NLS). •A method of nuclear import has not been elucidated. •Beak and feather disease virus (BFDV) capsid NLS was crystallized with importin α. •The structure showed BFDV NLS binding to the major site of importin α. •Result shows implications for mechanism of nuclear transport for all circoviruses. -- Abstract: Circoviruses represent a rapidly increasing genus of viruses that infect a variety of vertebrates. Replication requires shuttling viral molecules into the host cell nucleus, a process facilitated by capsid-associated protein (Cap). Whilst a nuclear localization signal (NLS) has been shown to mediatemore » nuclear translocation, the mode of nuclear transport remains to be elucidated. To better understand this process, beak and feather disease virus (BFDV) Cap NLS was crystallized with nuclear import receptor importin-α (Impα). Diffraction yielded structural data to 2.9 Å resolution, and the binding site on both Impα and BFDV Cap NLS were well resolved. The binding mechanism for the major site is likely conserved across circoviruses as supported by the similarity of NLSs in circovirus Caps. This finding illuminates a crucial step for infection of host cells by this viral family, and provides a platform for rational drug design against the binding interface.« less

Downgrading Nuclear Facilities to Radiological Facilities

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jarry, Jeffrey F.; Farr, Jesse Oscar; Duran, Leroy

2015-08-01

Based on inventory reductions and the use of alternate storage facilities, the Sandia National Laboratories (SNL) downgraded 4 SNL Hazard Category 3 (HC-3) nuclear facilities to less-than-HC-3 radiological facilities. SNL’s Waste Management and Pollution Prevention Department (WMPPD) managed the HC-3 nuclear facilities and implemented the downgrade. This paper will examine the downgrade process,

Testing quantum chromodynamics in electroproduction

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brodsky, S.J.

1987-05-01

The exclusive channels in electroproduction are discussed. The study of color transparency, the formation zone, and other novel aspects of QCD by measuring exclusive reactions inside nuclear targets is covered. Diffractive electroproduction channels are discussed, and exclusive nuclear processes in QCD are examined. Non-additivity of nuclear structure functions (EMC effect) is also discussed, as well as jet coalescence in electroproduction. (LEW)

Everybody's Scared--But Life Goes On: Coping, Defense and Action in the Face of Nuclear Threat.

ERIC Educational Resources Information Center

Haste, Helen

1989-01-01

Presents model of sequence of processes by which people deal with recurrent fears about nuclear war, drawing on risk perception and stress paradigms. Shows activism to be but one coping mechanism rather than the logical outcome of effective coping. Discusses implications for psychologists concerned about nuclear threat. (Author/NB)

Watermelons Not War! A Support Book for Parenting in the Nuclear Age.

ERIC Educational Resources Information Center

Cloud, Kate; And Others

The Nuclear Education Project (NEP), a group of five women concerned about parenting in a nuclear age, developed this guide to help parents and others develop a sense of hope and promote a greater involvement in the democratic political process. Chapter I, "The Heart of the Matter," presents sections on answering possible questions children might…

10 CFR 140.107 - Appendix G-Form of indemnity agreement with licensees processing plutonium for use in plutonium...

Code of Federal Regulations, 2012 CFR

2012-01-01

... policies as proof of financial protection. 140.107 Section 140.107 Energy NUCLEAR REGULATORY COMMISSION... specified in Item 2 of the Attachment and in the form of the nuclear energy liability insurance policy... liability of any Nuclear Energy Liability-Property Insurance Association policy designated in Item 5 of the...

10 CFR 140.107 - Appendix G-Form of indemnity agreement with licensees processing plutonium for use in plutonium...

Code of Federal Regulations, 2013 CFR

2013-01-01

... policies as proof of financial protection. 140.107 Section 140.107 Energy NUCLEAR REGULATORY COMMISSION... specified in Item 2 of the Attachment and in the form of the nuclear energy liability insurance policy... liability of any Nuclear Energy Liability-Property Insurance Association policy designated in Item 5 of the...

10 CFR 140.107 - Appendix G-Form of indemnity agreement with licensees processing plutonium for use in plutonium...

Code of Federal Regulations, 2014 CFR

2014-01-01

... policies as proof of financial protection. 140.107 Section 140.107 Energy NUCLEAR REGULATORY COMMISSION... specified in Item 2 of the Attachment and in the form of the nuclear energy liability insurance policy... liability of any Nuclear Energy Liability-Property Insurance Association policy designated in Item 5 of the...

10 CFR 140.107 - Appendix G-Form of indemnity agreement with licensees processing plutonium for use in plutonium...

Code of Federal Regulations, 2010 CFR

2010-01-01

... policies as proof of financial protection. 140.107 Section 140.107 Energy NUCLEAR REGULATORY COMMISSION... specified in Item 2 of the Attachment and in the form of the nuclear energy liability insurance policy... liability of any Nuclear Energy Liability-Property Insurance Association policy designated in Item 5 of the...

10 CFR 140.107 - Appendix G-Form of indemnity agreement with licensees processing plutonium for use in plutonium...

Code of Federal Regulations, 2011 CFR

2011-01-01

... policies as proof of financial protection. 140.107 Section 140.107 Energy NUCLEAR REGULATORY COMMISSION... specified in Item 2 of the Attachment and in the form of the nuclear energy liability insurance policy... liability of any Nuclear Energy Liability-Property Insurance Association policy designated in Item 5 of the...

High-Temperature Nucleosynthesis Processes on the Proton-Rich Side of Stability: the Alpha-Rich Freezeout and the rp^2-Process

NASA Astrophysics Data System (ADS)

Meyer, Bradley S.

2001-10-01

Nucleosynthesis on the proton-rich side of stability has at least two intriguing aspects. First, the most abundant of the stable iron-group isotopes, such as ^48Ti, ^52Cr, and ^56,57Fe, are synthesized as proton-rich, radioactive parents in alpha-rich freezeouts from equilibrium. The production of these radioactive progenitors depends in large measure on reactions on the proton-rich side of stability. The second intriguing aspect is that explosive nucleosynthesis in a hydrogen-rich environment (namely, the rp-process) may be associated with exotic astrophysical settings, such as x-ray bursts, and may be responsible for production of some of the light p-process nuclei (for example, ^92,94Mo and ^96,98Ru). We have developed web-based tools to help nuclear physicists determine which nuclear reactions on the proton-rich side of stability govern the nucleosynthesis in these processes. For the alpha-rich freezeout, one may determine the effect of any one of 2,140 reactions on the yield of any isotope in the nuclear reaction network with the web calculator. As a relevant example, I will discuss the governing role of ^57Ni (n,p)^57Co in the synthesis of the important astronomical observable ^57Co. As for explosive, proton-rich burning, I will discuss the synthesis of p-process nuclei in the repetitive rp-process (the rp^2-process). Movies of the rp^2-process illustrate its important features and give some indications of the important nuclear reactions.

U.S. and Russian Collaboration in the Area of Nuclear Forensics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kristo, M J

2007-10-22

Nuclear forensics has become increasingly important in the fight against illicit trafficking in nuclear and other radioactive materials. The illicit trafficking of nuclear materials is, of course, an international problem; nuclear materials may be mined and milled in one country, manufactured in a second country, diverted at a third location, and detected at a fourth. There have been a number of articles in public policy journals in the past year that call for greater interaction between the U. S. and the rest of the world on the topic of nuclear forensics. Some believe that such international cooperation would help providemore » a more certain capability to identify the source of the nuclear material used in a terrorist event. An improved international nuclear forensics capability would also be important as part of the IAEA verification toolkit, particularly linked to increased access provided by the additional protocol. A recent study has found that, although international progress has been made in securing weapons-usable HEU and Pu, the effort is still insufficient. They found that nuclear material, located in 40 countries, could be obtained by terrorists and criminals and used for a crude nuclear weapon. Through 2006, the IAEA Illicit Trafficking Database had recorded a total of 607 confirmed events involving illegal possession, theft, or loss of nuclear and other radioactive materials. Although it is difficult to predict the future course of such illicit trafficking, increasingly such activities are viewed as significant threats that merit the development of special capabilities. As early as April, 1996, nuclear forensics was recognized at the G-8 Summit in Moscow as an important element of an illicit nuclear trafficking program. Given international events over the past several years, the value and need for nuclear forensics seems greater than ever. Determining how and where legitimate control of nuclear material was lost and tracing the route of the material from diversion through interdiction are important goals for nuclear forensics and attribution. It is equally important to determine whether additional devices or materials that pose a threat to public safety are also available. Finding the answer to these questions depends on determining the source of the material and its method of production. Nuclear forensics analysis and interpretation provide essential insights into methods of production and sources of illicit radioactive materials. However, they are most powerful when combined with other sources of information, including intelligence and traditional detective work. The certainty of detection and punishment for those who remove nuclear materials from legitimate control provides the ultimate deterrent for such diversion and, ultimately, for the intended goal of such diversion, including nuclear terrorism or proliferation. Consequently, nuclear forensics is an integral part of 'nuclear deterrence' in the 21st century. Nuclear forensics will always be limited by the diagnostic information inherent in the interdicted material. Important markers for traditional forensics (fingerprints, stray material, etc.) can be eliminated or obscured, but many nuclear materials have inherent isotopic or chemical characteristics that serve as unequivocal markers of specific sources, production processes, or transit routes. The information needed for nuclear forensics goes beyond that collected for most commercial and international verification activities. Fortunately, the international nuclear engineering enterprise has a restricted number of conspicuous process steps that makes the interpretation process easier. Ultimately, though, it will always be difficult to distinguish between materials that reflect similar source or production histories, but are derived from disparate sites. Due to the significant capital costs of the equipment and the specialized expertise of the personnel, work in the field of nuclear forensics has been restricted so far to a handful of national and international laboratories. There are a limited number of specialists who have experience working with interdicted nuclear materials and affiliated evidence. Therefore, a knowledge management system that utilizes information resources relevant to nuclear forensic and attribution signatures, processes, origins, and pathways, allowing subject matter experts to access the right information in order to interpret forensics data and draw appropriate conclusions, is essential. In order to determine the origin, point of diversion of the nuclear material, and those responsible for the unauthorized transfer, close relationships are required between governments who maintain inventories and data of fissile or other radioactive materials. Numerous databases exist in many countries and organizations that could be valuable for the future development and application of nuclear forensics.« less

National Labs and Nuclear Emergency Response

NASA Astrophysics Data System (ADS)

Budil, Kimberly

2015-04-01

The DOE national laboratories, and in particular the three NNSA national security laboratories, have long supported a broad suite of national nuclear security missions for the U.S. government. The capabilities, infrastructure and base of expertise developed to support the U.S. nuclear weapons stockpile have been applied to such challenges as stemming nuclear proliferation, understanding the nuclear capabilities of adversaries, and assessing and countering nuclear threats including essential support to nuclear emergency response. This talk will discuss the programs that are underway at the laboratories and the essential role that science and technology plays therein. Nuclear scientists provide expertise, fundamental understanding of nuclear materials, processes and signatures, and tools and technologies to aid in the identification and mitigation of nuclear threats as well as consequence management. This talk will also discuss the importance of direct engagement with the response community, which helps to shape research priorities and to enable development of useful tools and techniques for responders working in the field. National Labs and Nuclear Emergency Response.

Nuclear Condensation during Mouse Erythropoiesis Requires Caspase-3-Mediated Nuclear Opening.

PubMed

Zhao, Baobing; Mei, Yang; Schipma, Matthew J; Roth, Eric Wayne; Bleher, Reiner; Rappoport, Joshua Z; Wickrema, Amittha; Yang, Jing; Ji, Peng

2016-03-07

Mammalian erythropoiesis involves chromatin condensation that is initiated in the early stage of terminal differentiation. The mechanisms of chromatin condensation during erythropoiesis are unclear. Here, we show that the mouse erythroblast forms large, transient, and recurrent nuclear openings that coincide with the condensation process. The opening lacks nuclear lamina, nuclear pore complexes, and nuclear membrane, but it is distinct from nuclear envelope changes that occur during apoptosis and mitosis. A fraction of the major histones are released from the nuclear opening and degraded in the cytoplasm. We demonstrate that caspase-3 is required for the nuclear opening formation throughout terminal erythropoiesis. Loss of caspase-3 or ectopic expression of a caspase-3 non-cleavable lamin B mutant blocks nuclear opening formation, histone release, chromatin condensation, and terminal erythroid differentiation. We conclude that caspase-3-mediated nuclear opening formation accompanied by histone release from the opening is a critical step toward chromatin condensation during erythropoiesis in mice. Copyright © 2016 Elsevier Inc. All rights reserved.

Nuclear condensation during mouse erythropoiesis requires caspase-3-mediated nuclear opening

PubMed Central

Zhao, Baobing; Mei, Yang; Schipma, Matthew J; Roth, Eric Wayne; Bleher, Reiner; Rappoport, Joshua Z.; Wickrema, Amittha; Yang, Jing; Ji, Peng

2016-01-01

SUMMARY Mammalian erythropoiesis involves chromatin condensation that is initiated in the early stage of terminal differentiation. The mechanisms of chromatin condensation during erythropoiesis are unclear. Here, we show that the mouse erythroblast forms large, transient, and recurrent nuclear openings that coincide with the condensation process. The opening lacks nuclear lamina, nuclear pore complexes, and nuclear membrane, but it is distinct from nuclear envelope changes that occur during apoptosis and mitosis. A fraction of the major histones are released from the nuclear opening and degraded in the cytoplasm. We demonstrate that caspase-3 is required for the nuclear opening formation throughout terminal erythropoiesis. Loss of caspase-3 or ectopic expression of a caspase-3 non-cleavable lamin B mutant blocks nuclear opening formation, histone release, chromatin condensation, and terminal erythroid differentiation. We conclude that caspase-3-mediated nuclear opening formation accompanied by histone release from the opening is a critical step towards chromatin condensation during erythropoiesis in mice. PMID:26954545

Critical Need for Plutonium and Uranium Isotopic Standards with Lower Uncertainties

DOE PAGES

Mathew, Kattathu Joseph; Stanley, Floyd E.; Thomas, Mariam R.; ...

2016-09-23

Certified reference materials (CRMs) traceable to national and international safeguards database are a critical prerequisite for ensuring that nuclear measurement systems are free of systematic biases. CRMs are used to validate measurement processes associated with nuclear analytical laboratories. Diverse areas related to nuclear safeguards are impacted by the quality of the CRM standards available to analytical laboratories. These include: nuclear forensics, radio-chronometry, national and international safeguards, stockpile stewardship, nuclear weapons infrastructure and nonproliferation, fuel fabrication, waste processing, radiation protection, and environmental monitoring. For the past three decades the nuclear community is confronted with the strange situation that improvements in measurementmore » data quality resulting from the improved accuracy and precision achievable with modern multi-collector mass spectrometers could not be fully exploited due to large uncertainties associated with CRMs available from New Brunswick Laboratory (NBL) that are used for instrument calibration and measurement control. Similar conditions prevail for both plutonium and uranium isotopic standards and for impurity element standards in uranium matrices. Herein, the current status of U and Pu isotopic standards available from NBL is reviewed. Critical areas requiring improvement in the quality of the nuclear standards to enable the U. S. and international safeguards community to utilize the full potential of modern multi-collector mass spectrometer instruments are highlighted.« less

Quantitative morphology in canine cutaneous soft tissue sarcomas.

PubMed

Simeonov, R; Ananiev, J; Gulubova, M

2015-12-01

Stained cytological specimens from 24 dogs with spontaneous soft tissue sarcomas [fibrosarcoma (n = 8), liposarcoma (n = 8) and haemangiopericytoma (n = 8)], and 24 dogs with reactive connective tissue lesions [granulation tissue (n = 12) and dermal fibrosis (n = 12)] were analysed by computer-assisted nuclear morphometry. The studied morphometric parameters were: mean nuclear area (MNA; µm(2)), mean nuclear perimeter (MNP; µm), mean nuclear diameter (MND mean; µm), minimum nuclear diameter (Dmin; µm) and maximum nuclear diameter (Dmax; µm). The study aimed to evaluate (1) possibility for quantitative differentiation of soft tissue sarcomas from reactive connective tissue lesions and (2) by using cytomorphometry, to differentiate the various histopathological soft tissue sarcomas subtypes in dogs. The mean values of all nuclear cytomorphometric parameters (except for Dmax) were statistically significantly higher in reactive connective tissue processes than in soft tissue sarcomas. At the same time, however, there were no considerable differences among the different sarcoma subtypes. The results demonstrated that the quantitative differentiation of reactive connective tissue processes from soft tissue sarcomas in dogs is possible, but the same was not true for the different canine soft tissue sarcoma subtypes. Further investigations on this topic are necessary for thorough explication of the role of quantitative morphology in the diagnostics of mesenchymal neoplasms and tumour-like fibrous lesions in dogs. © 2014 John Wiley & Sons Ltd.

Experience in implementation of «Nuclear Knowledge Management» course at the National Research Nuclear University MEPhI

NASA Astrophysics Data System (ADS)

Geraskin, N. I.; Kosilov, A. N.

2017-01-01

This paper describes the experience of teaching «Nuclear Knowledge Management» course at the National Research Nuclear University MEPhI (NRNU MEPhI). Currently, the course is implemented both in engineer and master degree programs and is attended by over 50 students. Goal, objectives and syllabus of the course are discussed in detail. A special attention is paid to practical exercises and final examination options in the case of small and large student groups. The course is supported by the Cyber Learning Platform for Nuclear Education and Training (CLP4NET), developed by the IAEA. The experience of NRNU MEPhI lecturers assisting in conducting the International School of Nuclear Knowledge Management, held annually in Trieste (Italy), is described with a special attention to the fact, that the course has passed the certification process at Academic Council of NRNU MEPhI. In 2014 and 2015 the course has been recognized as one of the best ones in NRNU MEPhI. Finally, perspectives of «Nuclear Knowledge Management» course are considered. They include increase of the course duration, introduction of the course into the learning process of other departments and institutions of the university, and transferring the course to other members of the Association «Consortium of ROSATOM supporting universities».

Nuclear structure and dynamics with density functional theory

NASA Astrophysics Data System (ADS)

Stetcu, Ionel

2015-10-01

Even in the absence of ab initio methods capable of tackling heavy nuclei without restrictions, one can obtain an ab initio description of ground-state properties by means of the density functional theory (DFT), and its extension to superfluid systems in its local variant, the superfluid local density approximation (SLDA). Information about the properties of excited states can be obtained in the same framework by using an extension to the time-dependent (TD) phenomena. Unlike other approaches in which the nuclear structure information is used as a separate input into reaction models, the TD approach treats on the same footing the nuclear structure and dynamics, and is well suited to provide more reliable description for a large number of processes involving heavy nuclei, from the nuclear response to electroweak probes, to nuclear reactions, such as neutron-induced reactions, or nuclear fusion and fission. Such processes, sometimes part of integrated nuclear systems, have important applications in astrophysics, energy production, global security, etc. In this talk, I will present the simulation of a simple reaction, that is the Coulomb excitation of a 238U nucleus, and discuss the application of the TD-DFT formalism to the description of induced fission. I gratefully acknowledge partial support of the U.S. Department of Energy through an Early Career Award of the LANL/LDRD Program.

Critical Need for Plutonium and Uranium Isotopic Standards with Lower Uncertainties

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mathew, Kattathu Joseph; Stanley, Floyd E.; Thomas, Mariam R.

Certified reference materials (CRMs) traceable to national and international safeguards database are a critical prerequisite for ensuring that nuclear measurement systems are free of systematic biases. CRMs are used to validate measurement processes associated with nuclear analytical laboratories. Diverse areas related to nuclear safeguards are impacted by the quality of the CRM standards available to analytical laboratories. These include: nuclear forensics, radio-chronometry, national and international safeguards, stockpile stewardship, nuclear weapons infrastructure and nonproliferation, fuel fabrication, waste processing, radiation protection, and environmental monitoring. For the past three decades the nuclear community is confronted with the strange situation that improvements in measurementmore » data quality resulting from the improved accuracy and precision achievable with modern multi-collector mass spectrometers could not be fully exploited due to large uncertainties associated with CRMs available from New Brunswick Laboratory (NBL) that are used for instrument calibration and measurement control. Similar conditions prevail for both plutonium and uranium isotopic standards and for impurity element standards in uranium matrices. Herein, the current status of U and Pu isotopic standards available from NBL is reviewed. Critical areas requiring improvement in the quality of the nuclear standards to enable the U. S. and international safeguards community to utilize the full potential of modern multi-collector mass spectrometer instruments are highlighted.« less

Lead iron phosphate glass as a containment medium for disposal of high-level nuclear waste

DOEpatents

Boatner, Lynn A.; Sales, Brian C.

1989-01-01

Lead-iron phosphate glasses containing a high level of Fe.sub.2 O.sub.3 for use as a storage medium for high-level radioactive nuclear waste. By combining lead-iron phosphate glass with various types of simulated high-level nuclear waste, a highly corrosion resistant, homogeneous, easily processed glass can be formed. For corroding solutions at 90.degree. C., with solution pH values in the range between 5 and 9, the corrosion rate of the lead-iron phosphate nuclear waste glass is at least 10.sup.2 to 10.sup.3 times lower than the corrosion rate of a comparable borosilicate nuclear waste glass. The presence of Fe.sub.2 O.sub.3 in forming the lead-iron phosphate glass is critical. Lead-iron phosphate nuclear waste glass can be prepared at temperatures as low as 800.degree. C., since they exhibit very low melt viscosities in the 800.degree. to 1050.degree. C. temperature range. These waste-loaded glasses do not readily devitrify at temperatures as high as 550.degree. C. and are not adversely affected by large doses of gamma radiation in H.sub.2 O at 135.degree. C. The lead-iron phosphate waste glasses can be prepared with minimal modification of the technology developed for processing borosilicate glass nuclear wasteforms.

Method for cleaning solution used in nuclear fuel reprocessing

DOEpatents

Tallent, O.K.; Crouse, D.J.; Mailen, J.C.

1980-12-17

Nuclear fuel processing solution consisting of tri-n-butyl phosphate and dodecane, with a complex of uranium, plutonium, or zirconium and with a solvent degradation product such as di-n-butyl phosphate therein, is contacted with an aqueous solution of a salt formed from hydrazine and either a dicarboxylic acid or a hydroxycarboxylic acid, thereby removing the aforesaid complex from the processing solution.

Microstructural processes in irradiated materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Byun, Thak Sang; Morgan, Dane; Jiao, Zhijie

2016-04-01

This is an editorial article (preface) for the publication of symposium papers in the Journal of Nuclear materials: These proceedings contain the papers presented at two symposia, the Microstructural Processes in Irradiated Materials (MPIM) and Characterization of Nuclear Reactor Materials and Components with Neutron and Synchrotron Radiation, held in the TMS 2015, 144th Annual Meeting & Exhibition at Walt Disney World, Orlando, Florida, USA on March 15–19, 2015.

Nuclear Weapons. National Nuclear Security Administration’s Plans for Its Uranium Processing Facility Should Better Reflect Funding Estimates and Technology Readiness

DTIC Science & Technology

2010-11-01

metal. Recovery extraction centrifugal contactors A process that uses solvent to extract uranium for purposes of purification. Agile machining A...extraction centrifugal contactors 5 6 Yes 6 No Agile machining 5 5 No 6 No Chip management 5 6 Yes 6 No Special casting 3 6 Yes 6 No Source: GAO

Method for cleaning solution used in nuclear fuel reprocessing

DOEpatents

Tallent, Othar K.; Crouse, David J.; Mailen, James C.

1982-01-01

Nuclear fuel processing solution consisting of tri-n-butyl phosphate and dodecane, with a complex of uranium, plutonium, or zirconium and with a solvent degradation product such as di-n-butyl phosphate therein, is contacted with an aqueous solution of a salt formed from hydrazine and either a dicarboxylic acid or a hydroxycarboxylic acid, thereby removing the aforesaid complex from the processing solution.

U.S. Nuclear Regulatory Commission natural analogue research program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kovach, L.A.; Ott, W.R.

1995-09-01

This article describes the natural analogue research program of the U.S. Nuclear Regulatory Commission (US NRC). It contains information on the regulatory context and organizational structure of the high-level radioactive waste research program plan. It also includes information on the conditions and processes constraining selection of natural analogues, describes initiatives of the US NRC, and describes the role of analogues in the licensing process.

Studying the processes relating to oxidation of organic substances contained in the coolant of thermal and nuclear power stations

NASA Astrophysics Data System (ADS)

Khodyrev, B. N.; Krichevtsov, A. L.; Sokolyuk, A. A.

2010-07-01

A radical-chain mechanism governing thermal-oxidation destruction of organic substances contained in the coolant of thermal and nuclear power stations is considered. Hypotheses on the chemical nature of antioxidation properties of amines are presented. Theoretical conjectures about the fundamental processes through which protective amine films are formed on the surface of metals are suggested.

Status Update on the NCRP Scientific Committee SC 5-1 Report: Decision Making for Late-Phase Recovery from Nuclear or Radiological Incidents - 13450

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, S.Y.

2013-07-01

In August 2008, the U.S. Department of Homeland Security (DHS) issued its final Protective Action Guide (PAG) for radiological dispersal device (RDD) and improvised nuclear device (IND) incidents. This document specifies protective actions for public health during the early and intermediate phases and cleanup guidance for the late phase of RDD or IND incidents, and it discusses approaches to implementing the necessary actions. However, while the PAG provides specific guidance for the early and intermediate phases, it prescribes no equivalent guidance for the late-phase cleanup actions. Instead, the PAG offers a general description of a complex process using a site-specificmore » optimization approach. This approach does not predetermine cleanup levels but approaches the problem from the factors that would bear on the final agreed-on cleanup levels. Based on this approach, the decision-making process involves multifaceted considerations including public health, the environment, and the economy, as well as socio-political factors. In an effort to fully define the process and approach to be used in optimizing late-phase recovery and site restoration following an RDD or IND incident, DHS has tasked the NCRP with preparing a comprehensive report addressing all aspects of the optimization process. Preparation of the NCRP report is a three-year (2010-2013) project assigned to a scientific committee, the Scientific Committee (SC) 5-1; the report was initially titled, Approach to Optimizing Decision Making for Late- Phase Recovery from Nuclear or Radiological Terrorism Incidents. Members of SC 5-1 represent a broad range of expertise, including homeland security, health physics, risk and decision analysis, economics, environmental remediation and radioactive waste management, and communication. In the wake of the Fukushima nuclear accident of 2011, and guided by a recent process led by the White House through a Principal Level Exercise (PLE), the optimization approach has since been expanded to include off-site contamination from major nuclear power plant accidents as well as other nuclear or radiological incidents. The expanded application under the current guidance has thus led to a broadened scope of the report, which is reflected in its new title, Decision Making for Late-Phase Recovery from Nuclear or Radiological Incidents. The NCRP report, which is due for publication in 2013, will substantiate the current DHS guidance by clarifying and elaborating on the processes required for the development and implementation of procedures for optimizing decision making for late-phase recovery, enabling the establishment of cleanup goals on a site-specific basis. The report will contain a series of topics addressing important issues related to the long-term recovery from nuclear or radiological incidents. Special topics relevant to supporting the optimization of the decision-making process will include cost-benefit analysis, radioactive waste management, risk communication, stakeholder interaction, risk assessment, and decontamination approaches and techniques. The committee also evaluated past nuclear and radiological incidents for their relevance to the report, including the emerging issues associated with the Fukushima nuclear accident. Thus, due to the commonality of the late-phase issues (such as the potential widespread contamination following an event), the majority of the information pertaining to the response in the late-phase decision-making period, including site-specific optimization framework and approach, could be used or adapted for use in case of similar situations that are not due to terrorism, such as those that would be caused by major nuclear facility accidents or radiological incidents. To ensure that the report and the NCRP recommendations are current and relevant to the effective implementation of federal guidance, SC 5-1 has actively coordinated with the agencies of interest and other relevant stakeholders throughout the duration of the project. The resulting report will be an important resource to guide those involved in late-phase recovery efforts following a nuclear or radiological incident. (authors)« less

Impact of nuclear transmutations on the primary damage production: The example of Ni based steels

NASA Astrophysics Data System (ADS)

Luneville, Laurence; Sublet, Jean Christphe; Simeone, David

2018-07-01

The recent nuclear evaluations describe more accurately the elastic and inelastic neutron-atoms interactions and allow calculating more realistically primary damage induced by nuclear reactions. Even if these calculations do not take into account relaxation processes occurring at the end of the displacement cascade (calculations are performed within the Binary Collision Approximation), they can accurately describe primary and recoil spectra in different reactors opening the door for simulating aging of nuclear materials with Ion Beam facilities. Since neutrons are only sensitive to isotopes, these spectra must be calculated weighting isotope spectra by the isotopic composition of materials under investigation. To highlight such a point, primary damage are calculated in pure Ni exhibiting a meta-stable isotope produced under neutron flux by inelastic neutron-isotope processes. These calculations clearly point out that the instantaneous primary damage production, the displacement per atom rate (dpa/s), responsible for the micro-structure evolution, strongly depends on the 59N i isotopic fractions closely related to the inelastic neutron isotope processes. Since the isotopic composition of the meta-stable isotope vanishes for large fluences, the long term impact of this isotope does not largely modify drastically the total dpa number in Ni based steels materials irradiate in nuclear plants.

The Acceptance Strategy for Nuclear Power Plant In Indonesia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Suhaemi, Tjipta; Syaukat, Achmad

2010-06-22

Indonesia has planned to build nuclear power plants. Some feasibility studies have been conducted intensively. However, the processes of NPP introduction are still uncertain. National Energy Plan in Indonesia, which has been made by some governmental agencies, does not yet give positive impact to the government decision to construct the nuclear power plant (NPP). This paper discusses the process of NPP introduction in Indonesia, which has been colored with debate of stakeholder and has delayed decision for go-nuclear. The technology paradigm is used to promote NPP as an alternative of reliable energy resources. This paradigm should be complemented with internationalmore » politic-economic point of view. The international politic-economic point of view shows that structural powers, consisting of security, production, finance, and knowledge structures, within which the NPP is introduced, have dynamic characteristics. The process of NPP introduction in Indonesia contains some infrastructure development (R and D, legislation, regulation, energy planning, site study, public acceptance efforts, etc), but they need a better coherent NPP implementation program and NPP Acceptance Program. Strategic patterns for NPP acceptance described in this paper are made by considering nuclear regulation development and the interest of basic domestic participation. The first NPP program in Indonesia having proven technology and basic domestic participation is and important milestone toward and optimal national energy-mix.« less

Quantization of Differences Between Atomic and Nuclear Rest Masses and Self-organization of Atoms and Nuclei

NASA Astrophysics Data System (ADS)

Gareev, F. A.; Zhidkova, I. E.

2007-03-01

We come to the conclusion that all atomic models based on either the Newton equation and the Kepler laws, or the Maxwell equations, or the Schrodinger and Dirac equations are in reasonable agreement with experimental data. We can only suspect that these equations are grounded on the same fundamental principle(s) which is (are) not known or these equations can be transformed into each other. We proposed a new mechanism of LENR: cooperative processes in the whole system nuclei + atoms + condensed matter - nuclear reactions in plasma - can occur at smaller threshold energies than the corresponding ones on free constituents. We were able to quantize phenomenologically the first time the differences between atomic and nuclear rest masses by the formula: δδM =n1/n2 X 0.0076294 (in MeV/ c^2), ni=1,2,3,.... Note that this quantization rule is justified for atoms and nuclei with different A, N and Z and the nuclei and atoms represent a coherent synchronized systems - a complex of coupled oscillators (resonators). The cooperative resonance synchronization mechanisms can explain how electron volt (atomic-) scale processes can induce and control nuclear MeV (nuclear-) scale processes and reactions., F.A. Gareev, I.E. Zhidkova, E-print arXiv Nucl-th/ 0610002 2006.

Dynamic nuclear polarization assisted spin diffusion for the solid effect case.

PubMed

Hovav, Yonatan; Feintuch, Akiva; Vega, Shimon

2011-02-21

The dynamic nuclear polarization (DNP) process in solids depends on the magnitudes of hyperfine interactions between unpaired electrons and their neighboring (core) nuclei, and on the dipole-dipole interactions between all nuclei in the sample. The polarization enhancement of the bulk nuclei has been typically described in terms of a hyperfine-assisted polarization of a core nucleus by microwave irradiation followed by a dipolar-assisted spin diffusion process in the core-bulk nuclear system. This work presents a theoretical approach for the study of this combined process using a density matrix formalism. In particular, solid effect DNP on a single electron coupled to a nuclear spin system is considered, taking into account the interactions between the spins as well as the main relaxation mechanisms introduced via the electron, nuclear, and cross-relaxation rates. The basic principles of the DNP-assisted spin diffusion mechanism, polarizing the bulk nuclei, are presented, and it is shown that the polarization of the core nuclei and the spin diffusion process should not be treated separately. To emphasize this observation the coherent mechanism driving the pure spin diffusion process is also discussed. In order to demonstrate the effects of the interactions and relaxation mechanisms on the enhancement of the nuclear polarization, model systems of up to ten spins are considered and polarization buildup curves are simulated. A linear chain of spins consisting of a single electron coupled to a core nucleus, which in turn is dipolar coupled to a chain of bulk nuclei, is considered. The interaction and relaxation parameters of this model system were chosen in a way to enable a critical analysis of the polarization enhancement of all nuclei, and are not far from the values of (13)C nuclei in frozen (glassy) organic solutions containing radicals, typically used in DNP at high fields. Results from the simulations are shown, demonstrating the complex dependences of the DNP-assisted spin diffusion process on variations of the relevant parameters. In particular, the effect of the spin lattice relaxation times on the polarization buildup times and the resulting end polarization are discussed, and the quenching of the polarizations by the hyperfine interaction is demonstrated.

Psychoanalysis and the nuclear threat

DOE Office of Scientific and Technical Information (OSTI.GOV)

Levine, H.B.; Jacobs, D.; Rubin, L.J.

1988-01-01

{ital Psychoanalysis and the Nuclear Threat} provides coverage of the dynamic and clinical considerations that follow from life in the nuclear age. Of special clinical interest are chapters dealing with the developmental consequences of the nuclear threat in childhood, adolescence, and adulthood, and those exploring the technical issues raised by the occurrence in analytic and psychotherapeutic hours of material related to the nuclear threat. Additional chapters bring a psychoanalytic perspective to bear on such issues as the need to have enemies, silence as the real crime, love, work, and survival in the nuclear age, the relationship of the nuclear threatmore » to issues of mourning and melancholia, apocalyptic fantasies, the paranoid process, considerations of the possible impact of gender on the nuclear threat, and the application of psychoanalytic thinking to nuclear arms strategy. Finally, the volume includes the first case report in the English language---albeit a brief psychotherapy---involving the treatment of a Hiroshima survivor.« less

Nuclear sensor signal processing circuit

DOEpatents

Kallenbach, Gene A [Bosque Farms, NM; Noda, Frank T [Albuquerque, NM; Mitchell, Dean J [Tijeras, NM; Etzkin, Joshua L [Albuquerque, NM

2007-02-20

An apparatus and method are disclosed for a compact and temperature-insensitive nuclear sensor that can be calibrated with a non-hazardous radioactive sample. The nuclear sensor includes a gamma ray sensor that generates tail pulses from radioactive samples. An analog conditioning circuit conditions the tail-pulse signals from the gamma ray sensor, and a tail-pulse simulator circuit generates a plurality of simulated tail-pulse signals. A computer system processes the tail pulses from the gamma ray sensor and the simulated tail pulses from the tail-pulse simulator circuit. The nuclear sensor is calibrated under the control of the computer. The offset is adjusted using the simulated tail pulses. Since the offset is set to zero or near zero, the sensor gain can be adjusted with a non-hazardous radioactive source such as, for example, naturally occurring radiation and potassium chloride.

Chromatin condensation during terminal erythropoiesis.

PubMed

Zhao, Baobing; Yang, Jing; Ji, Peng

2016-09-02

Mammalian terminal erythropoiesis involves gradual but dramatic chromatin condensation steps that are essential for cell differentiation. Chromatin and nuclear condensation is followed by a unique enucleation process, which is believed to liberate more spaces for hemoglobin enrichment and enable the generation of a physically flexible mature red blood cell. Although these processes have been known for decades, the mechanisms are still unclear. Our recent study reveals an unexpected nuclear opening formation during mouse terminal erythropoiesis that requires caspase-3 activity. Major histones, except H2AZ, are partially released from the opening, which is important for chromatin condensation. Block of the nuclear opening through caspase inhibitor or knockdown of caspase-3 inhibits chromatin condensation and enucleation. We also demonstrate that nuclear opening and histone release are cell cycle regulated. These studies reveal a novel mechanism for chromatin condensation in mammalia terminal erythropoiesis.

A Stochastic Model of Space Radiation Transport as a Tool in the Development of Time-Dependent Risk Assessment

NASA Technical Reports Server (NTRS)

Kim, Myung-Hee Y.; Nounu, Hatem N.; Ponomarev, Artem L.; Cucinotta, Francis A.

2011-01-01

A new computer model, the GCR Event-based Risk Model code (GERMcode), was developed to describe biophysical events from high-energy protons and heavy ions that have been studied at the NASA Space Radiation Laboratory (NSRL) [1] for the purpose of simulating space radiation biological effects. In the GERMcode, the biophysical description of the passage of heavy ions in tissue and shielding materials is made with a stochastic approach that includes both ion track structure and nuclear interactions. The GERMcode accounts for the major nuclear interaction processes of importance for describing heavy ion beams, including nuclear fragmentation, elastic scattering, and knockout-cascade processes by using the quantum multiple scattering fragmentation (QMSFRG) model [2]. The QMSFRG model has been shown to be in excellent agreement with available experimental data for nuclear fragmentation cross sections

Quantum Information Processing with Large Nuclear Spins in GaAs Semiconductors

NASA Astrophysics Data System (ADS)

Leuenberger, Michael N.; Loss, Daniel; Poggio, M.; Awschalom, D. D.

2003-03-01

We propose an implementation for quantum information processing based on coherent manipulations of nuclear spins I=3/2 in GaAs semiconductors. We describe theoretically an NMR method which involves multiphoton transitions and which exploits the nonequidistance of nuclear spin levels due to quadrupolar splittings. Starting from known spin anisotropies we derive effective Hamiltonians in a generalized rotating frame, valid for arbitrary I, which allow us to describe the nonperturbative time evolution of spin states generated by magnetic rf fields. We identify an experimentally observable regime for multiphoton Rabi oscillations. In the nonlinear regime, we find Berry phase interference. Ref: PRL 89, 207601 (2002).

Preparation of nuclear fuel spheres by flotation-internal gelation

DOEpatents

Haas, P.A.; Fowler, V.L.; Lloyd, M.H.

1984-12-21

A simplified internal gelation process is claimed for the preparation of gel spheres of nuclear fuels. The process utilizes perchloroethylene as a gelation medium. Gelation is accomplished by directing droplets of a nuclear fuel broth into a moving volume of hot perchloroethylene (about 85/sup 0/C) in a trough. Gelation takes place as the droplets float on the surface of the perchloroethylene and the resultant gel spheres are carried directly into an ager column which is attached to the trough. The aged spheres are disengaged from the perchloroethylene on a moving screen and are deposited in an aqueous wash column. 3 figs.

Nuclear forensics of a non-traditional sample: Neptunium

DOE Office of Scientific and Technical Information (OSTI.GOV)

Doyle, Jamie L.; Schwartz, Daniel; Tandon, Lav

Recent nuclear forensics cases have focused primarily on plutonium (Pu) and uranium (U) materials. By definition however, nuclear forensics can apply to any diverted nuclear material. This includes neptunium (Np), an internationally safeguarded material like Pu and U, that could offer a nuclear security concern if significant quantities were found outside of regulatory control. This case study couples scanning electron microscopy (SEM) with quantitative analysis using newly developed specialized software, to evaluate a non-traditional nuclear forensic sample of Np. Here, the results of the morphological analyses were compared with another Np sample of known pedigree, as well as other traditionalmore » actinide materials in order to determine potential processing and point-of-origin.« less

Nuclear forensics of a non-traditional sample: Neptunium

DOE PAGES

Doyle, Jamie L.; Schwartz, Daniel; Tandon, Lav

2016-05-16

Recent nuclear forensics cases have focused primarily on plutonium (Pu) and uranium (U) materials. By definition however, nuclear forensics can apply to any diverted nuclear material. This includes neptunium (Np), an internationally safeguarded material like Pu and U, that could offer a nuclear security concern if significant quantities were found outside of regulatory control. This case study couples scanning electron microscopy (SEM) with quantitative analysis using newly developed specialized software, to evaluate a non-traditional nuclear forensic sample of Np. Here, the results of the morphological analyses were compared with another Np sample of known pedigree, as well as other traditionalmore » actinide materials in order to determine potential processing and point-of-origin.« less

Non-equilibrium radiation nuclear reactor

NASA Technical Reports Server (NTRS)

Thom, K.; Schneider, R. T. (Inventor)

1978-01-01

An externally moderated thermal nuclear reactor is disclosed which is designed to provide output power in the form of electromagnetic radiation. The reactor is a gaseous fueled nuclear cavity reactor device which can operate over wide ranges of temperature and pressure, and which includes the capability of processing and recycling waste products such as long-lived transuranium actinides. The primary output of the device may be in the form of coherent radiation, so that the reactor may be utilized as a self-critical nuclear pumped laser.

System Design for a Nuclear Electric Spacecraft Utilizing Out-of-core Thermionic Conversion

NASA Technical Reports Server (NTRS)

Estabrook, W. C.; Phillips, W. M.; Hsieh, T.

1976-01-01

Basic guidelines are presented for a nuclear space power system which utilizes heat pipes to transport thermal power from a fast nuclear reactor to an out of core thermionic converter array. Design parameters are discussed for the nuclear reactor, heat pipes, thermionic converters, shields (neutron and gamma), waste heat rejection systems, and the electrical bus bar-cable system required to transport the high current/low voltage power to the processing equipment. Dimensions are compatible with shuttle payload bay constraints.

Conditional Depletion of Nuclear Proteins by the Anchor Away System (ms# CP-10-0125)

PubMed Central

Fan, Xiaochun; Geisberg, Joseph V.; Wong, Koon Ho; Jin, Yi

2011-01-01

Nuclear proteins play key roles in the regulation of many important cellular processes. In Saccharomyces cerevisiae, many genes encoding nuclear proteins are essential. Here we describe a method termed Anchor Away that can be used to conditionally and rapidly deplete nuclear proteins of interest. It involves conditional export of the protein of interest out of the nucleus and its subsequent sequestration in the cytoplasm. This method can be used to simultaneously deplete multiple proteins from nucleus. PMID:21225637

Plasma filtering techniques for nuclear waste remediation

DOE PAGES

Gueroult, Renaud; Hobbs, David T.; Fisch, Nathaniel J.

2015-04-24

Nuclear waste cleanup is challenged by the handling of feed stocks that are both unknown and complex. Plasma filtering, operating on dissociated elements, offers advantages over chemical methods in processing such wastes. The costs incurred by plasma mass filtering for nuclear waste pretreatment, before ultimate disposal, are similar to those for chemical pretreatment. However, significant savings might be achieved in minimizing the waste mass. As a result, this advantage may be realized over a large range of chemical waste compositions, thereby addressing the heterogeneity of legacy nuclear waste.

Incineration of nuclear waste by accelerator

NASA Astrophysics Data System (ADS)

Martino, J.; Fioni, G.; Leray, S.

1998-10-01

An important international effort is devoted to find a suitable solution to incinerate radioactive nuclear waste issued from conventional power plants and from nuclear disarmament. Practically all innovative projects consist of a sub critical system driven by an external neutron source obtained by spallation induced by a high intensity proton accelerator irradiating a heavy target. New nuclear data measurements are necessary for the realization of these systems, in particular a good knowledge of the spallation process and of the neutron cross sections for transuranic elements are essential.

Compensation as Means for Local Acceptance The Case of the Final Disposal of Spent Nuclear Fuel in Eurajoki, Finland

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kojo, M.

The paper sheds light on the local negotiations on compensation as a part of the site selection for the spent nuclear fuel repository in Finland. The negotiation took place between the representatives of the Municipality of Eurajoki, the nuclear power company Teollisuuden Voima Ltd (TVO) and the nuclear waste management company Posiva Ltd in the late 1990's. The compensation negotiation process and the development of the requirements are elucidated in detail on the basis of the analysis of the minutes of the meetings of the Vuojoki working party. The paper helps to understand the smooth site selection process in Finland.more » The context of the local decision-making is viewed from the policy, institutional and economic aspect. It is concluded in the paper that when trying to understand the progress of the Finnish site selection process more emphasis should be put on the role of TVO, the economic dependency of the Municipality of Eurajoki on TVO and the partnership between TVO and the leading local politicians. (authors)« less

An evaluation of UO2-CNT composites made by SPS as an accident tolerant nuclear fuel pellet and the feasibility of SPS as an economical fabrication process for the nuclear fuel cycle

NASA Astrophysics Data System (ADS)

Cartas, Andrew R.

The innovative and advanced purpose of this study is to understand and establish proper sintering procedures for Spark Plasma Sintering process in order to fabricate high density, high thermal conductivity UO2 -CNT pellets. Mixing quality and chemical reactions have been investigated by field emission scanning electron microscopy (FESEM), wavelength dispersive spectroscopy (WDS), and X-ray diffraction (XRD). The effect of various types of CNTs on the mixing and sintering quality of UO2-CNT pellets with SPS processing have been examined. The Archimedes Immersion Method, laser flash method, and FE-SEM will be used to investigate the density, thermal conductivity, grain size, pinning effects, and CNT dispersion of fabricated UO2-CNT pellets. Pre-fabricated CNT's were added to UO 2 powder and dispersed via sonication and/or ball milling and then made into composite nuclear pellets. An investigation of the economic impact of SPS on the nuclear fuel cycle for producing pure and composite UO2 fuels was conducted.

Establishment of Korean Nuclear Ombudsman System Importing Compensation and Insurance Concept for Residents

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hyun Seok Ko; Yong Min Kim; Young Wook Lee

2006-07-01

In Korea, the nuclear power generation is grown technically well. Already, 20 nuclear reactors are operated, and approximate they supply the 40% of whole the consumption of electric power. This is the driving force of Korean industrial development. Besides, Korean Standard Nuclear Power Plant that was developed by Korean self-technique with nuclear plant technique independence, Ul-Chin 6 has started the commercial operation. Advanced Korean Standard Nuclear Power Plant, new Gori 1, 2 constructions are commenced. But, past days Korean situation is that intention of residents is neglected in the decision making process of nuclear power plant construction and operation. Inmore » existing decision making process, it is regarded as the role of public opinion is secondary, and the problem of decision making process is that public is persuaded and believed. So, in decision making process, the public opinion is considered restrictively, there is not the actual public participation. Therefore the dissatisfaction of public is increased continuously, and in Korea, bad recognition about nuclear power is getting full. The method of public participation for complement of this problem is public hearing or ombudsman system. The public hearing is ensuring public participation before decision of a case, and ombudsman is the system that elevates the public satisfaction through continuous feedback of public requirement to occur in deciding and performing the matters. In Korean situation, that present 20 nuclear reactors are operated and also the place of radioactive waste repository has been decided, not only the introduction of public hearing to decide the coming matter but also the operation of ombudsman system to continuously correct and collect the public requirements about the matter to already decided and operated is necessary. In Korea, administration type ombudsman is operated now. But, it has operated without basic element at the aspect of organization, function and phase. So it is not established a firm phase as right relief body to be believed by public with lack of independence, authority and specialty. Therefore the establishment of organization that can be the role as special ombudsman organization about sensitive and special matter like nuclear matter is necessary. Definite establishment element of ombudsman system is to introduce of congress type ombudsman element, to be permanent standing system ombudsman, to limit jurisdiction extent and have strong authority, to be able to access easily, to be composed of legal and nuclear specialist. One of important requirements of resident is compensation. So, based on the resident compensation theory about aversion equipment, ombudsman system should be established introducing the insurance theory through risk management as functional background for appropriate compensation. (authors)« less

The Nuclear Barcode: a New Taggant for Identifying Explosives

NASA Astrophysics Data System (ADS)

Seman, James; Johnson, Catherine; Castaño, Carlos

2017-06-01

Creating an effective taggant system for explosives is a challenging problem since the taggant used must be designed to endure the detonation process. A new taggant for use in explosives has been recently developed and named the `nuclear barcode'. The nuclear barcode tags explosives by adding low concentrations of eight different elements to the explosive, and then reads the tag from the post-blast residue using neutron activation analysis (NAA) to identify the elements and their concentrations. The nuclear barcode can be used to identify explosives after detonation by sampling the post-blast residue that is deposited due to incomplete reaction of the explosives. This method of tagging explosives creates an identifying taggant that survives detonation as NAA detects atomic nuclei as opposed to using any chemical or physical properties of the taggant that don't always survive the detonation process. Additional advantages this taggant method offers is ease of recovery of the taggant after detonation, and a total of 25.6 billion possible taggants as currently conceived, which enables the nuclear barcode to be used to tag individual batches of explosives. This paper describes the development of the nuclear barcode taggant system and its potential use in the explosives industry.

Developing the nuclear idea: concept, technique, and process.

PubMed

Billow, Richard M

2013-10-01

I introduce an approach to group that has remained undeveloped in the literature, but represents an essence of relationally oriented group psychotherapy. Evolving from the verbalizations and enactments through which the group symbolizes and becomes known-a nuclear idea takes shape. It emerges from the nucleus of the group process: co-created from intersubjective forces and locations that cannot be fully specified, yet may be possible to observe, name, and utilize clinically. Groups organize themselves by developing nuclear ideas, with the therapist's active participation. They are vehicles through which a group comes to think about its thinking: not only what it thinks, but also how it thinks, or chooses not to think, and when and why. Developing the nuclear idea provides a framework for how the therapist-and the group itself-goes about the task of containing. With its emphasis on meaning and the development of meaning as transformational, the concept of the nuclear idea supplements the whole group, interpersonal, and intrapsychic lenses through which the therapist comes to understand group experience and base interventions. Clinical vignettes illustrate how the therapist may develop nuclear ideas thematically, conceptualize further, and negotiate meaning with the co-participation of other group members.

Nuclear-renewable hybrid energy systems: Opportunities, interconnections, and needs

DOE PAGES

Ruth, Mark F.; Zinaman, Owen R.; Antkowiak, Mark; ...

2013-12-20

As the U.S. energy system evolves, the amount of electricity from variable-generation sources is likely to increase, which could result in additional times when electricity demand is lower than available production. Therefore, purveyors of technologies that traditionally have provided base-load electricity—such as nuclear power plants—can explore new operating procedures to deal with the associated market signals. Concurrently, innovations in nuclear reactor design coupled with sophisticated control systems now allow for more complex apportionment of heat within an integrated system such as one linked to energy-intensive chemical processes. Our paper explores one opportunity – nuclear-renewable hybrid energy systems. These are definedmore » as integrated facilities comprised of nuclear reactors, renewable energy generation, and industrial processes that can simultaneously address the need for grid flexibility, greenhouse gas emission reductions, and optimal use of investment capital. Six aspects of interaction (interconnections) between elements of nuclear-renewable hybrid energy systems are identified: Thermal, electrical, chemical, hydrogen, mechanical, and information. In addition, system-level aspects affect selection, design, and operation of this hybrid system type. Throughout the paper, gaps and research needs are identified to promote further exploration of the topic.« less

Nuclear driven water decomposition plant for hydrogen production

NASA Technical Reports Server (NTRS)

Parker, G. H.; Brecher, L. E.; Farbman, G. H.

1976-01-01

The conceptual design of a hydrogen production plant using a very-high-temperature nuclear reactor (VHTR) to energize a hybrid electrolytic-thermochemical system for water decomposition has been prepared. A graphite-moderated helium-cooled VHTR is used to produce 1850 F gas for electric power generation and 1600 F process heat for the water-decomposition process which uses sulfur compounds and promises performance superior to normal water electrolysis or other published thermochemical processes. The combined cycle operates at an overall thermal efficiency in excess of 45%, and the overall economics of hydrogen production by this plant have been evaluated predicated on a consistent set of economic ground rules. The conceptual design and evaluation efforts have indicated that development of this type of nuclear-driven water-decomposition plant will permit large-scale economic generation of hydrogen in the 1990s.

Digital Signal Processing Methods for Safety Systems Employed in Nuclear Power Industry

NASA Astrophysics Data System (ADS)

Popescu, George

Some of the major safety concerns in the nuclear power industry focus on the readiness of nuclear power plant safety systems to respond to an abnormal event, the security of special nuclear materials in used nuclear fuels, and the need for physical security to protect personnel and reactor safety systems from an act of terror. Routine maintenance and tests of all nuclear reactor safety systems are performed on a regular basis to confirm the ability of these systems to operate as expected. However, these tests do not determine the reliability of these safety systems and whether the systems will perform for the duration of an accident and whether they will perform their tasks without failure after being engaged. This research has investigated the progression of spindle asynchronous error motion determined from spindle accelerations to predict bearings failure onset. This method could be applied to coolant pumps that are essential components of emergency core cooling systems at all nuclear power plants. Recent security upgrades mandated by the Nuclear Regulatory Commission and the Department of Homeland Security have resulted in implementation of multiple physical security barriers around all of the commercial and research nuclear reactors in the United States. A second part of this research attempts to address an increased concern about illegal trafficking of Special Nuclear Materials (SNM). This research describes a multi element scintillation detector system designed for non - invasive (passive) gamma ray surveillance for concealed SNM that may be within an area or sealed in a package, vehicle or shipping container. Detection capabilities of the system were greatly enhanced through digital signal processing, which allows the combination of two very powerful techniques: 1) Compton Suppression (CS) and 2) Pulse Shape Discrimination (PSD) with less reliance on complicated analog instrumentation.

Nuclear Explosion and Infrasound Event Resources of the SMDC Monitoring Research Program

DTIC Science & Technology

2008-09-01

2008 Monitoring Research Review: Ground-Based Nuclear Explosion Monitoring Technologies 928 Figure 7. Dozens of detected infrasound signals from...investigate alternative detection schemes at the two infrasound arrays based on frequency-wavenumber (fk) processing and the F-statistic. The results of... infrasound signal - detection processing schemes. REFERENCES Bahavar, M., B. Barker, J. Bennett, R. Bowman, H. Israelsson, B. Kohl, Y-L. Kung, J. Murphy

Nuclear Criticality Safety Data Book

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hollenbach, D. F.

The objective of this document is to support the revision of criticality safety process studies (CSPSs) for the Uranium Processing Facility (UPF) at the Y-12 National Security Complex (Y-12). This design analysis and calculation (DAC) document contains development and justification for generic inputs typically used in Nuclear Criticality Safety (NCS) DACs to model both normal and abnormal conditions of processes at UPF to support CSPSs. This will provide consistency between NCS DACs and efficiency in preparation and review of DACs, as frequently used data are provided in one reference source.

Reduced Order Models Via Continued Fractions Applied to Control Systems,

DTIC Science & Technology

1980-09-01

a simple * model of a nuclear reactor power generator [20, 21]. The heat generating process of a nuclear reactor is dependent upon the mechanism...called fission (a fragmentation of matter). The power generated by this process is directly related to the population of neutrons, n~t) and can be...150) 6(t ()n~t) - c(t) (151) where 6k(t) 6 kc(t)-an(t) (152) The variable 6k(t) is the input to the process and is given the name "reactivity". It is

Implementation of Quantum Private Queries Using Nuclear Magnetic Resonance

NASA Astrophysics Data System (ADS)

Wang, Chuan; Hao, Liang; Zhao, Lian-Jie

2011-08-01

We present a modified protocol for the realization of a quantum private query process on a classical database. Using one-qubit query and CNOT operation, the query process can be realized in a two-mode database. In the query process, the data privacy is preserved as the sender would not reveal any information about the database besides her query information, and the database provider cannot retain any information about the query. We implement the quantum private query protocol in a nuclear magnetic resonance system. The density matrix of the memory registers are constructed.

Dynamics of Lamin-A Processing Following Precursor Accumulation

PubMed Central

Liu, Qian; Kim, Dae In; Syme, Janet; LuValle, Phyllis; Burke, Brian; Roux, Kyle J.

2010-01-01

Lamin A (LaA) is a component of the nuclear lamina, an intermediate filament meshwork that underlies the inner nuclear membrane (INM) of the nuclear envelope (NE). Newly synthesized prelamin A (PreA) undergoes extensive processing involving C-terminal farnesylation followed by proteolysis yielding non-farnesylated mature lamin A. Different inhibitors of these processing events are currently used therapeutically. Hutchinson-Gilford Progeria Syndrome (HGPS) is most commonly caused by mutations leading to an accumulation of a farnesylated LaA isoform, prompting a clinical trial using farnesyltransferase inhibitors (FTI) to reduce this modification. At therapeutic levels, HIV protease inhibitors (PI) can unexpectedly inhibit the final processing step in PreA maturation. We have examined the dynamics of LaA processing and associated cellular effects during PI or FTI treatment and following inhibitor washout. While PI reversibility was rapid, with respect to both LaA maturation and associated cellular phenotype, recovery from FTI treatment was more gradual. FTI reversibility is influenced by both cell type and rate of proliferation. These results suggest a less static lamin network than has previously been observed. PMID:20526372

Thermal hydraulic feasibility assessment of the hot conditioning system and process

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heard, F.J.

1996-10-10

The Spent Nuclear Fuel Project was established to develop engineered solutions for the expedited removal, stabilization, and storage of spent nuclear fuel from the K Basins at the U.S. Department of Energy`s Hanford Site in Richland, Washington. A series of analyses have been completed investigating the thermal-hydraulic performance and feasibility of the proposed Hot Conditioning System and process for the Spent Nuclear Fuel Project. The analyses were performed using a series of thermal-hydraulic models that could respond to all process and safety-related issues that may arise pertaining to the Hot Conditioning System. The subject efforts focus on independently investigating, quantifying,more » and establishing the governing heat production and removal mechanisms, flow distributions within the multi-canister overpack, and performing process simulations for various purge gases under consideration for the Hot Conditioning System, as well as obtaining preliminary results for comparison with and verification of other analyses, and providing technology- based recommendations for consideration and incorporation into the Hot Conditioning System design bases.« less

Process for immobilizing plutonium into vitreous ceramic waste forms

DOEpatents

Feng, Xiangdong; Einziger, Robert E.

1997-01-01

Disclosed is a method for converting spent nuclear fuel and surplus plutonium into a vitreous ceramic final waste form wherein spent nuclear fuel is bound in a crystalline matrix which is in turn bound within glass.

Process for immobilizing plutonium into vitreous ceramic waste forms

DOEpatents

Feng, X.; Einziger, R.E.

1997-08-12

Disclosed is a method for converting spent nuclear fuel and surplus plutonium into a vitreous ceramic final waste form wherein spent nuclear fuel is bound in a crystalline matrix which is in turn bound within glass.

Process for immobilizing plutonium into vitreous ceramic waste forms

DOEpatents

Feng, X.; Einziger, R.E.

1997-01-28

Disclosed is a method for converting spent nuclear fuel and surplus plutonium into a vitreous ceramic final waste form wherein spent nuclear fuel is bound in a crystalline matrix which is in turn bound within glass.

Theoretical physics: Quarks fuse to release energy

NASA Astrophysics Data System (ADS)

Miller, Gerald A.

2017-11-01

In nuclear fusion, energy is produced by the rearrangement of protons and neutrons. The discovery of an analogue of this process involving particles called quarks has implications for both nuclear and particle physics. See Letter p.89

Around and beyond 53BP1 Nuclear Bodies.

PubMed

Fernandez-Vidal, Anne; Vignard, Julien; Mirey, Gladys

2017-12-05

Within the nucleus, sub-nuclear domains define territories where specific functions occur. Nuclear bodies (NBs) are dynamic structures that concentrate nuclear factors and that can be observed microscopically. Recently, NBs containing the p53 binding protein 1 (53BP1), a key component of the DNA damage response, were defined. Interestingly, 53BP1 NBs are visualized during G1 phase, in daughter cells, while DNA damage was generated in mother cells and not properly processed. Unlike most NBs involved in transcriptional processes, replication has proven to be key for 53BP1 NBs, with replication stress leading to the formation of these large chromatin domains in daughter cells. In this review, we expose the composition and organization of 53BP1 NBs and focus on recent findings regarding their regulation and dynamics. We then concentrate on the importance of the replication stress, examine the relation of 53BP1 NBs with DNA damage and discuss their dysfunction.

A review of carbide fuel corrosion for nuclear thermal propulsion applications

NASA Astrophysics Data System (ADS)

Pelaccio, Dennis G.; El-Genk, Mohamed S.; Butt, Darryl P.

1993-10-01

At the operation conditions of interest in nuclear thermal propulsion reactors, carbide materials have been known to exhibit a number of life limiting phenomena. These include the formation of liquid, loss by vaporization, creep and corresponding gas flow restrictions, and local corrosion and fuel structure degradation due to excessive mechanical and/or thermal loading. In addition, the radiation environment in the reactor core can produce a substantial change in its local physical properties, which can produce high thermal stresses and corresponding stress fractures (cracking). Time-temperature history and cyclic operation of the nuclear reactor can also accelerate some of these processes. The University of New Mexico's Institute for Space Nuclear Power Studies, under NASA sponsorship has recently initiated a study to model the complicated hydrogen corrosion process. In support of this effort, an extensive review of the open literature was performed, and a technical expert workshop was conducted. This paper summarizes the results of this review.

A Review of Carbide Fuel Corrosion for Nuclear Thermal Propulsion Applications

NASA Astrophysics Data System (ADS)

Pelaccio, Dennis G.; El-Genk, Mohamed S.; Butt, Darryl P.

1994-07-01

At the operation conditions of interest in nuclear thermal propulsion reactors, carbide materials have been known to exhibit a number of life limiting phenomena. These include the formation of liquid, loss by vaporization, creep and corresponding gas flow restrictions, and local corrosion and fuel structure degradation due to excessive mechanical and/or thermal loading. In addition, the radiation environment in the reactor core can produce a substantial change in its local physical properties, which can produce high thermal stresses and corresponding stress fractures (cracking). Time-temperature history and cyclic operation of the nuclear reactor can also accelerate some of these processes. The University of New Mexico's Institute for Space Nuclear Power Studies, under NASA sponsorship has recently initiated a study to model the complicated hydrogen corrosion process. In support of this effort, an extensive review of the open literature was performed, and a technical expert workshop was conducted. This paper summarizes the results of this review.

Fission-Produced 99Mo Without a Nuclear Reactor.

PubMed

Youker, Amanda J; Chemerisov, Sergey D; Tkac, Peter; Kalensky, Michael; Heltemes, Thad A; Rotsch, David A; Vandegrift, George F; Krebs, John F; Makarashvili, Vakho; Stepinski, Dominique C

2017-03-01

99 Mo, the parent of the widely used medical isotope 99m Tc, is currently produced by irradiation of enriched uranium in nuclear reactors. The supply of this isotope is encumbered by the aging of these reactors and concerns about international transportation and nuclear proliferation. Methods: We report results for the production of 99 Mo from the accelerator-driven subcritical fission of an aqueous solution containing low enriched uranium. The predominately fast neutrons generated by impinging high-energy electrons onto a tantalum convertor are moderated to thermal energies to increase fission processes. The separation, recovery, and purification of 99 Mo were demonstrated using a recycled uranyl sulfate solution. Conclusion: The 99 Mo yield and purity were found to be unaffected by reuse of the previously irradiated and processed uranyl sulfate solution. Results from a 51.8-GBq 99 Mo production run are presented. © 2017 by the Society of Nuclear Medicine and Molecular Imaging.

Impact of Leishmania Infection on Host Macrophage Nuclear Physiology and Nucleopore Complex Integrity

PubMed Central

Isnard, Amandine; Christian, Jan G.; Kodiha, Mohamed; Stochaj, Ursula; McMaster, W. Robert; Olivier, Martin

2015-01-01

The protease GP63 is an important virulence factor of Leishmania parasites. We previously showed that GP63 reaches the perinuclear area of host macrophages and that it directly modifies nuclear translocation of the transcription factors NF-κB and AP-1. Here we describe for the first time, using molecular biology and in-depth proteomic analyses, that GP63 alters the host macrophage nuclear envelope, and impacts on nuclear processes. Our results suggest that GP63 does not appear to use a classical nuclear localization signal common between Leishmania species for import, but degrades nucleoporins, and is responsible for nuclear transport alterations. In the nucleoplasm, GP63 activity accounts for the degradation and mislocalization of proteins involved amongst others in gene expression and in translation. Collectively, our data indicates that Leishmania infection strongly affects nuclear physiology, suggesting that targeting of nuclear physiology may be a strategy beneficial for virulent Leishmania parasites. PMID:25826301

Current Development of Nuclear Thermal Propulsion technologies at the Center for Space Nuclear Research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robert C. O'Brien; Steven K. Cook; Nathan D. Jerred

Nuclear power and propulsion has been considered for space applications since the 1950s. Between 1955 and 1972 the US built and tested over twenty nuclear reactors / rocket engines in the Rover/NERVA programs1. The Aerojet Corporation was the prime contractor for the NERVA program. Modern changes in environmental laws present challenges for the redevelopment of the nuclear rocket. Recent advances in fuel fabrication and testing options indicate that a nuclear rocket with a fuel composition that is significantly different from those of the NERVA project can be engineered; this may be needed to ensure public support and compliance with safetymore » requirements. The Center for Space Nuclear Research (CSNR) is pursuing a number of technologies, modeling and testing processes to further the development of safe, practical and affordable nuclear thermal propulsion systems.« less

Nuclear Computational Low Energy Initiative (NUCLEI)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Reddy, Sanjay K.

This is the final report for University of Washington for the NUCLEI SciDAC-3. The NUCLEI -project, as defined by the scope of work, will develop, implement and run codes for large-scale computations of many topics in low-energy nuclear physics. Physics to be studied include the properties of nuclei and nuclear decays, nuclear structure and reactions, and the properties of nuclear matter. The computational techniques to be used include Quantum Monte Carlo, Configuration Interaction, Coupled Cluster, and Density Functional methods. The research program will emphasize areas of high interest to current and possible future DOE nuclear physics facilities, including ATLAS andmore » FRIB (nuclear structure and reactions, and nuclear astrophysics), TJNAF (neutron distributions in nuclei, few body systems, and electroweak processes), NIF (thermonuclear reactions), MAJORANA and FNPB (neutrino-less double-beta decay and physics beyond the Standard Model), and LANSCE (fission studies).« less

Constraining the astrophysical origin of the p-nuclei through nuclear physics and meteoritic data.

PubMed

Rauscher, T; Dauphas, N; Dillmann, I; Fröhlich, C; Fülöp, Zs; Gyürky, Gy

2013-06-01

A small number of naturally occurring, proton-rich nuclides (the p-nuclei) cannot be made in the s- and r-processes. Their origin is not well understood. Massive stars can produce p-nuclei through photodisintegration of pre-existing intermediate and heavy nuclei. This so-called γ-process requires high stellar plasma temperatures and occurs mainly in explosive O/Ne burning during a core-collapse supernova. Although the γ-process in massive stars has been successful in producing a large range of p-nuclei, significant deficiencies remain. An increasing number of processes and sites has been studied in recent years in search of viable alternatives replacing or supplementing the massive star models. A large number of unstable nuclei, however, with only theoretically predicted reaction rates are included in the reaction network and thus the nuclear input may also bear considerable uncertainties. The current status of astrophysical models, nuclear input and observational constraints is reviewed. After an overview of currently discussed models, the focus is on the possibility to better constrain those models through different means. Meteoritic data not only provide the actual isotopic abundances of the p-nuclei but can also put constraints on the possible contribution of proton-rich nucleosynthesis. The main part of the review focuses on the nuclear uncertainties involved in the determination of the astrophysical reaction rates required for the extended reaction networks used in nucleosynthesis studies. Experimental approaches are discussed together with their necessary connection to theory, which is especially pronounced for reactions with intermediate and heavy nuclei in explosive nuclear burning, even close to stability.

Energetic electron processes fluorescence effects for structured nanoparticles X-ray analysis and nuclear medicine applications

NASA Astrophysics Data System (ADS)

Taborda, A.; Desbrée, A.; Carvalho, A.; Chaves, P. C.; Reis, M. A.

2016-08-01

Superparamagnetic iron oxide (SPIO) nanoparticles are widely used as contrast agents for nuclear magnetic resonance imaging (MRI), and can be modified for improved imaging or to become tissue-specific or even protein-specific. The knowledge of their detailed elemental composition characterisation and potential use in nuclear medicine applications, is, therefore, an important issue. X-ray fluorescence techniques such as particle induced X-ray emission (PIXE) or X-ray fluorescence spectrometry (XRF), can be used for elemental characterisation even in problematic situations where very little sample volume is available. Still, the fluorescence coefficient of Fe is such that, during the decay of the inner-shell ionised atomic structure, keV Auger electrons are produced in excess to X-rays. Since cross-sections for ionisation induced by keV electrons, for low atomic number atoms, are of the order of 103 barn, care should be taken to account for possible fluorescence effects caused by Auger electrons, which may lead to the wrong quantification of elements having atomic number lower than the atomic number of Fe. Furthermore, the same electron processes will occur in iron oxide nanoparticles containing 57Co, which may be used for nuclear medicine therapy purposes. In the present work, simple approximation algorithms are proposed for the quantitative description of radiative and non-radiative processes associated with Auger electrons cascades. The effects on analytical processes and nuclear medicine applications are quantified for the case of iron oxide nanoparticles, by calculating both electron fluorescence emissions and energy deposition on cell tissues where the nanoparticles may be embedded.

Human Factors and Information Operation for a Nuclear Power Space Vehicle

NASA Technical Reports Server (NTRS)

Trujillo, Anna C.; Brown-VanHoozer, S. Alenka

2002-01-01

This paper describes human-interactive systems needed for a crewed nuclear-enabled space mission. A synthesis of aircraft engine and nuclear power plant displays, biofeedback of sensory input, virtual control, brain mapping for control process and manipulation, and so forth are becoming viable solutions. These aspects must maintain the crew's situation awareness and performance, which entails a delicate function allocation between crew and automation.

Experience and advantages in implementation of educational program in network form at Department «Closed nuclear fuel cycle Technologies» of National Research Nuclear University «MEPhI»

NASA Astrophysics Data System (ADS)

Beygel‧, A. G.; Kutsenko, K. V.; Lavrukhin, A. A.; Magomedbekov, E. P.; Pershukov, V. A.; Sofronov, V. L.; Tyupina, E. A.; Zhiganov, A. N.

2017-01-01

The experience of implementation of the basic educational program of magistracy on direction «Nuclear Physics and Technologies» in a network form is presented. Examples of joint implementation of the educational process with employers organizations, other universities and intranet mobility of students are given.

Development of the Nuclear-Electronic Orbital Approach and Applications to Ionic Liquids and Tunneling Processes

DTIC Science & Technology

2010-02-24

electronic Schrodinger equation . In previous grant cycles, we implemented the NEO approach at the Hartree-Fock (NEO-HF),13 configuration interaction...electronic and nuclear molecular orbitals. The resulting electronic and nuclear Hartree-Fock-Roothaan equations are solved iteratively until self...directly into the standard Hartree- Fock-Roothaan equations , which are solved iteratively to self-consistency. The density matrix representation

JPRS Report, Proliferation Issues

DTIC Science & Technology

1991-08-08

from its processing plant at Valindaba, and fuel-fabrication plants at Valindaba and Pelindaba. where fuel rods for use at the Koeberg nuclear-power...construction of the fourth one. The pulsed reactor uses special elements of nuclear fuel The site of the proposed fourth nuclear power plant can enabling...chemical, and biological weapons, including delivery systems and the transfer of weapons-relevant technologies.] AFRICA SOUTH AFRICA Civilian Uses for

10 CFR 2.603 - Acceptance and docketing of application for early review of site suitability issues in a...

Code of Federal Regulations, 2012 CFR

2012-01-01

... processing, the Director of the Office of New Reactors or the Director of the Office of Nuclear Reactor... days. (b)(1) The Director of the Office of New Reactors or the Director of the Office of Nuclear... Nuclear Reactor Regulation, as appropriate, that they are complete. (c) If part one of the application is...

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barty, Christopher P.J.

Lasers and laser-based sources are now routinely used to control and manipulate nuclear processes, e.g. fusion, fission and resonant nuclear excitation. Two such “nuclear photonics” activities with the potential for profound societal impact will be reviewed in this presentation: the pursuit of laser-driven inertial confinement fusion at the National Ignition Facility and the development of laser-based, mono-energetic gamma-rays for isotope-specific detection, assay and imaging of materials.

FENDL: International reference nuclear data library for fusion applications

NASA Astrophysics Data System (ADS)

Pashchenko, A. B.; Wienke, H.; Ganesan, S.

1996-10-01

The IAEA Nuclear Data Section, in co-operation with several national nuclear data centres and research groups, has created the first version of an internationally available Fusion Evaluated Nuclear Data Library (FENDL-1). The FENDL library has been selected to serve as a comprehensive source of processed and tested nuclear data tailored to the requirements of the engineering design activity (EDA) of the ITER project and other fusion-related development projects. The present version of FENDL consists of the following sublibraries covering the necessary nuclear input for all physics and engineering aspects of the material development, design, operation and safety of the ITER project in its current EDA phase: FENDL/A-1.1: neutron activation cross-sections, selected from different available sources, for 636 nuclides, FENDL/D-1.0: nuclear decay data for 2900 nuclides in ENDF-6 format, FENDL/DS-1.0: neutron activation data for dosimetry by foil activation, FENDL/C-1.0: data for the fusion reactions D(d,n), D(d,p), T(d,n), T(t,2n), He-3(d,p) extracted from ENDF/B-6 and processed, FENDL/E-1.0:data for coupled neutron—photon transport calculations, including a data library for neutron interaction and photon production for 63 elements or isotopes, selected from ENDF/B-6, JENDL-3, or BROND-2, and a photon—atom interaction data library for 34 elements. The benchmark validation of FENDL-1 as required by the customer, i.e. the ITER team, is considered to be a task of high priority in the coming months. The well tested and validated nuclear data libraries in processed form of the FENDL-2 are expected to be ready by mid 1996 for use by the ITER team in the final phase of ITER EDA after extensive benchmarking and integral validation studies in the 1995-1996 period. The FENDL data files can be electronically transferred to users from the IAEA nuclear data section online system through INTERNET. A grand total of 54 (sub)directories with 845 files with total size of about 2 million blocks or about 1 Gigabyte (1 block = 512 bytes) of numerical data is currently available on-line.

Nuclear Lamins

PubMed Central

Dechat, Thomas; Adam, Stephen A.; Taimen, Pekka; Shimi, Takeshi; Goldman, Robert D.

2010-01-01

The nuclear lamins are type V intermediate filament proteins that are critically important for the structural properties of the nucleus. In addition, they are involved in the regulation of numerous nuclear processes, including DNA replication, transcription and chromatin organization. The developmentally regulated expression of lamins suggests that they are involved in cellular differentiation. Their assembly dynamic properties throughout the cell cycle, particularly in mitosis, are influenced by posttranslational modifications. Lamins may regulate nuclear functions by direct interactions with chromatin and determining the spatial organization of chromosomes within the nuclear space. They may also regulate chromatin functions by interacting with factors that epigenetically modify the chromatin or directly regulate replication or transcription. PMID:20826548

Myosin-1C uses a novel phosphoinositide-dependent pathway for nuclear localization.

PubMed

Nevzorov, Ilja; Sidorenko, Ekaterina; Wang, Weihuan; Zhao, Hongxia; Vartiainen, Maria K

2018-02-01

Accurate control of macromolecule transport between nucleus and cytoplasm underlines several essential biological processes, including gene expression. According to the canonical model, nuclear import of soluble proteins is based on nuclear localization signals and transport factors. We challenge this view by showing that nuclear localization of the actin-dependent motor protein Myosin-1C (Myo1C) resembles the diffusion-retention mechanism utilized by inner nuclear membrane proteins. We show that Myo1C constantly shuttles in and out of the nucleus and that its nuclear localization does not require soluble factors, but is dependent on phosphoinositide binding. Nuclear import of Myo1C is preceded by its interaction with the endoplasmic reticulum, and phosphoinositide binding is specifically required for nuclear import, but not nuclear retention, of Myo1C. Our results therefore demonstrate, for the first time, that membrane association and binding to nuclear partners is sufficient to drive nuclear localization of also soluble proteins, opening new perspectives to evolution of cellular protein sorting mechanisms. © 2018 The Authors. Published under the terms of the CC BY NC ND 4.0 license.

Porous nuclear fuel element for high-temperature gas-cooled nuclear reactors

DOEpatents

Youchison, Dennis L [Albuquerque, NM; Williams, Brian E [Pacoima, CA; Benander, Robert E [Pacoima, CA

2011-03-01

Porous nuclear fuel elements for use in advanced high temperature gas-cooled nuclear reactors (HTGR's), and to processes for fabricating them. Advanced uranium bi-carbide, uranium tri-carbide and uranium carbonitride nuclear fuels can be used. These fuels have high melting temperatures, high thermal conductivity, and high resistance to erosion by hot hydrogen gas. Tri-carbide fuels, such as (U,Zr,Nb)C, can be fabricated using chemical vapor infiltration (CVI) to simultaneously deposit each of the three separate carbides, e.g., UC, ZrC, and NbC in a single CVI step. By using CVI, the nuclear fuel may be deposited inside of a highly porous skeletal structure made of, for example, reticulated vitreous carbon foam.

Porous nuclear fuel element with internal skeleton for high-temperature gas-cooled nuclear reactors

DOEpatents

Youchison, Dennis L.; Williams, Brian E.; Benander, Robert E.

2013-09-03

Porous nuclear fuel elements for use in advanced high temperature gas-cooled nuclear reactors (HTGR's), and to processes for fabricating them. Advanced uranium bi-carbide, uranium tri-carbide and uranium carbonitride nuclear fuels can be used. These fuels have high melting temperatures, high thermal conductivity, and high resistance to erosion by hot hydrogen gas. Tri-carbide fuels, such as (U,Zr,Nb)C, can be fabricated using chemical vapor infiltration (CVI) to simultaneously deposit each of the three separate carbides, e.g., UC, ZrC, and NbC in a single CVI step. By using CVI, the nuclear fuel may be deposited inside of a highly porous skeletal structure made of, for example, reticulated vitreous carbon foam.

Reconstructing the public in old and new governance: a Korean case of nuclear energy policy.

PubMed

Kim, Hyomin

2014-04-01

Korean nuclear energy regulatory policies started to change from earlier exclusively technocratic policies into open dialogues after several anti-nuclear protests in the 1990s. However, technocratic policies still coexist with the new regulatory orientation towards openness, participation and institutional accountability. This paper analyzes Korean nuclear regulatory policies since approximately 2005 as a blend of old and new governance. The aim of the paper is not to decide whether new nuclear governance is deliberative or not by completely reviewing Korean nuclear policies after the 2000s. Instead, it provides an empirical account of how seemingly more participatory processes in decision-making entail new problems while they work with and reproduce social assumptions of different groups of the public.

Voltage-selective bidirectional polarization and coherent rotation of nuclear spins in quantum dots.

PubMed

Takahashi, R; Kono, K; Tarucha, S; Ono, K

2011-07-08

We propose and demonstrate that the nuclear spins of the host lattice in GaAs double quantum dots can be polarized in either of two opposite directions, parallel or antiparallel to an external magnetic field. The direction is selected by adjusting the dc voltage. This nuclear polarization manifests itself by repeated controlled electron-nuclear spin scattering in the Pauli spin-blockade state. Polarized nuclei are also controlled by means of nuclear magnetic resonance. This Letter confirms that the nuclear spins in quantum dots are long-lived quantum states with a coherence time of up to 1 ms, and may be a promising resource for quantum-information processing such as quantum memories for electron spin qubits.

Thermal diffusivity and nuclear spin relaxation: a continuous wave free precession NMR study.

PubMed

Venâncio, Tiago; Engelsberg, Mario; Azeredo, Rodrigo B V; Colnago, Luiz A

2006-07-01

Continuous wave free precession (CWFP) nuclear magnetic resonance is capable of yielding quantitative and easily obtainable information concerning the kinetics of processes that change the relaxation rates of the nuclear spins through the action of some external agent. In the present application, heat flow from a natural rubber sample to a liquid nitrogen thermal bath caused a large temperature gradient leading to a non-equilibrium temperature distribution. The ensuing local changes in the relaxation rates could be monitored by the decay of the CWFP signals and, from the decays, it was possible to ascertain the prevalence of a diffusive process and to obtain an average value for the thermal diffusivity.

Unifying Theory of Low-Energy Nuclear Reaction and Transmutation Processes in Deuterated/hydrogenated Metals, Acoustic Cavitation, Glow Discharge, and Deuteron Beam Experiments

NASA Astrophysics Data System (ADS)

Kim, Yeong E.; Zubarev, Alexander L.

The most basic theoretical challenge for understanding low-energy nuclear reaction (LENR) and transmutation reaction (LETR) in condensed matters is to find mechanisms by which the large Coulomb barrier between fusing nuclei can be overcome. A unifying theory of LENR and LETR has been developed to provide possible mechanisms for the LENR and LETR processes in matters based on high-density nano-scale and micro-scale quantum plasmas. It is shown that recently developed theoretical models based on Bose-Einstein Fusion (BEF) mechanism and Quantum Plasma Nuclear Fusion (QPNF) mechanism are applicable to the results of many different types of LENR and LETR experiments.

Upgrading the fuel-handling machine of the Novovoronezh nuclear power plant unit no. 5

NASA Astrophysics Data System (ADS)

Terekhov, D. V.; Dunaev, V. I.

2014-02-01

The calculation of safety parameters was carried out in the process of upgrading the fuel-handling machine (FHM) of the Novovoronezh nuclear power plant (NPP) unit no. 5 based on the results of quantitative safety analysis of nuclear fuel transfer operations using a dynamic logical-and-probabilistic model of the processing procedure. Specific engineering and design concepts that made it possible to reduce the probability of damaging the fuel assemblies (FAs) when performing various technological operations by an order of magnitude and introduce more flexible algorithms into the modernized FHM control system were developed. The results of pilot operation during two refueling campaigns prove that the total reactor shutdown time is lowered.

What the Erythrocytic Nuclear Alteration Frequencies Could Tell Us about Genotoxicity and Macrophage Iron Storage?

PubMed

Gomes, Juliana M M; Ribeiro, Heder J; Procópio, Marcela S; Alvarenga, Betânia M; Castro, Antônio C S; Dutra, Walderez O; da Silva, José B B; Corrêa Junior, José D

2015-01-01

Erythrocytic nuclear alterations have been considered as an indicative of organism's exposure to genotoxic agents. Due to their close relationship among their frequencies and DNA damages, they are considered excellent markers of exposure in eukaryotes. However, poor data has been found in literature concerning their genesis, differential occurrence and their life span. In this study, we use markers of cell viability; genotoxicity and cellular turn over in order to shed light to these events. Tilapia and their blood were exposed to cadmium in acute exposure and in vitro assays. They were analyzed using flow cytometry for oxidative stress and membrane disruption, optical microscopy for erythrocytic nuclear alteration, graphite furnace atomic absorption spectrometry for cadmium content in aquaria water, blood and cytochemical and analytical electron microscopy techniques for the hemocateretic aspects. The results showed a close relationship among the total nuclear alterations and cadmium content in the total blood and melanomacrophage centres area, mismatching reactive oxygen species and membrane damages. Moreover, nuclear alterations frequencies (vacuolated, condensed and blebbed) showed to be associated to cadmium exposure whereas others (lobed and bud) were associated to depuration period. Decrease on nuclear alterations frequencies was also associated with hemosiderin increase inside spleen and head kidney macrophages mainly during depurative processes. These data disclosure in temporal fashion the main processes that drive the nuclear alterations frequencies and their relationship with some cellular and systemic biomarkers.

NUCLEAR PORE ANCHOR, the Arabidopsis Homolog of Tpr/Mlp1/Mlp2/Megator, Is Involved in mRNA Export and SUMO Homeostasis and Affects Diverse Aspects of Plant Development[W

PubMed Central

Xu, Xianfeng Morgan; Rose, Annkatrin; Muthuswamy, Sivaramakrishnan; Jeong, Sun Yong; Venkatakrishnan, Sowmya; Zhao, Qiao; Meier, Iris

2007-01-01

Vertebrate Tpr and its yeast homologs Mlp1/Mlp2, long coiled-coil proteins of nuclear pore inner basket filaments, are involved in mRNA export, telomere organization, spindle pole assembly, and unspliced RNA retention. We identified Arabidopsis thaliana NUCLEAR PORE ANCHOR (NUA) encoding a 237-kD protein with similarity to Tpr. NUA is located at the inner surface of the nuclear envelope in interphase and in the vicinity of the spindle in prometaphase. Four T-DNA insertion lines were characterized, which comprise an allelic series of increasing severity for several correlating phenotypes, such as early flowering under short days and long days, increased abundance of SUMO conjugates, altered expression of several flowering regulators, and nuclear accumulation of poly(A)+ RNA. nua mutants phenocopy mutants of EARLY IN SHORT DAYS4 (ESD4), an Arabidopsis SUMO protease concentrated at the nuclear periphery. nua esd4 double mutants resemble nua and esd4 single mutants, suggesting that the two proteins act in the same pathway or complex, supported by yeast two-hybrid interaction. Our data indicate that NUA is a component of nuclear pore-associated steps of sumoylation and mRNA export in plants and that defects in these processes affect the signaling events of flowering time regulation and additional developmental processes. PMID:17513499

What the Erythrocytic Nuclear Alteration Frequencies Could Tell Us about Genotoxicity and Macrophage Iron Storage?

PubMed Central

Gomes, Juliana M. M.; Ribeiro, Heder J.; Procópio, Marcela S.; Alvarenga, Betânia M.; Castro, Antônio C. S.; Dutra, Walderez O.; da Silva, José B. B.; Corrêa Junior, José D.

2015-01-01

Erythrocytic nuclear alterations have been considered as an indicative of organism’s exposure to genotoxic agents. Due to their close relationship among their frequencies and DNA damages, they are considered excellent markers of exposure in eukaryotes. However, poor data has been found in literature concerning their genesis, differential occurrence and their life span. In this study, we use markers of cell viability; genotoxicity and cellular turn over in order to shed light to these events. Tilapia and their blood were exposed to cadmium in acute exposure and in vitro assays. They were analyzed using flow cytometry for oxidative stress and membrane disruption, optical microscopy for erythrocytic nuclear alteration, graphite furnace atomic absorption spectrometry for cadmium content in aquaria water, blood and cytochemical and analytical electron microscopy techniques for the hemocateretic aspects. The results showed a close relationship among the total nuclear alterations and cadmium content in the total blood and melanomacrophage centres area, mismatching reactive oxygen species and membrane damages. Moreover, nuclear alterations frequencies (vacuolated, condensed and blebbed) showed to be associated to cadmium exposure whereas others (lobed and bud) were associated to depuration period. Decrease on nuclear alterations frequencies was also associated with hemosiderin increase inside spleen and head kidney macrophages mainly during depurative processes. These data disclosure in temporal fashion the main processes that drive the nuclear alterations frequencies and their relationship with some cellular and systemic biomarkers. PMID:26619141

Nuclear waste transportation: case studies of identifying stakeholder risk information needs.

PubMed Central

Drew, Christina H; Grace, Deirdre A; Silbernagel, Susan M; Hemmings, Erin S; Smith, Alan; Griffith, William C; Takaro, Timothy K; Faustman, Elaine M

2003-01-01

The U.S. Department of Energy (DOE) is responsible for the cleanup of our nation's nuclear legacy, involving complex decisions about how and where to dispose of nuclear waste and how to transport it to its ultimate disposal site. It is widely recognized that a broad range of stakeholders and tribes should be involved in this kind of decision. All too frequently, however, stakeholders and tribes are only invited to participate by commenting on processes and activities that are near completion; they are not included in the problem formulation stages. Moreover, it is often assumed that high levels of complexity and uncertainty prevent meaningful participation by these groups. Considering the types of information that stakeholders and tribes need to be able to participate in the full life cycle of decision making is critical for improving participation and transparency of decision making. Toward this objective, the Consortium for Risk Evaluation with Stakeholder Participation (CRESP) participated in three public processes relating to nuclear waste transportation and disposal in 1997-1998. First, CRESP organized focus groups to identify concerns about nuclear waste transportation. Second, CRESP conducted exit surveys at regional public workshops held by DOE to get input from stakeholders on intersite waste transfer issues. Third, CRESP developed visual tools to synthesize technical information and allow stakeholders and tribes with varying levels of knowledge about nuclear waste to participate in meaningful discussion. In this article we share the results of the CRESP findings, discuss common themes arising from these interactions, and comment on special considerations needed to facilitate stakeholder and tribal participation in similar decision-making processes. PMID:12611653

Technical Application of Nuclear Fission

NASA Astrophysics Data System (ADS)

Denschlag, J. O.

The chapter is devoted to the practical application of the fission process, mainly in nuclear reactors. After a historical discussion covering the natural reactors at Oklo and the first attempts to build artificial reactors, the fundamental principles of chain reactions are discussed. In this context chain reactions with fast and thermal neutrons are covered as well as the process of neutron moderation. Criticality concepts (fission factor η, criticality factor k) are discussed as well as reactor kinetics and the role of delayed neutrons. Examples of specific nuclear reactor types are presented briefly: research reactors (TRIGA and ILL High Flux Reactor), and some reactor types used to drive nuclear power stations (pressurized water reactor [PWR], boiling water reactor [BWR], Reaktor Bolshoi Moshchnosti Kanalny [RBMK], fast breeder reactor [FBR]). The new concept of the accelerator-driven systems (ADS) is presented. The principle of fission weapons is outlined. Finally, the nuclear fuel cycle is briefly covered from mining, chemical isolation of the fuel and preparation of the fuel elements to reprocessing the spent fuel and conditioning for deposit in a final repository.

Dynamic high energy density plasma environments at the National Ignition Facility for nuclear science research

DOE PAGES

Cerjan, Ch J.; Bernstein, L.; Hopkins, L. Berzak; ...

2017-08-16

We present the generation of dynamic high energy density plasmas in the pico- to nano-second time domain at high-energy laser facilities affords unprecedented nuclear science research possibilities. At the National Ignition Facility (NIF), the primary goal of inertial confinement fusion research has led to the synergistic development of a unique high brightness neutron source, sophisticated nuclear diagnostic instrumentation, and versatile experimental platforms. These novel experimental capabilities provide a new path to investigate nuclear processes and structural effects in the time, mass and energy density domains relevant to astrophysical phenomena in a unique terrestrial environment. Some immediate applications include neutron capturemore » cross-section evaluation, fission fragment production, and ion energy loss measurement in electron-degenerate plasmas. More generally, the NIF conditions provide a singular environment to investigate the interplay of atomic and nuclear processes such as plasma screening effects upon thermonuclear reactivity. Lastly, achieving enhanced understanding of many of these effects will also significantly advance fusion energy research and challenge existing theoretical models.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gastelum, Zoe N.; Harvey, Julia B.

The International Atomic Energy Agency State Evaluation Process: The Role of Information Analysis in Reaching Safeguards Conclusions (Mathews et al. 2008), several examples of nonproliferation models using analytical software were developed that may assist the IAEA with collecting, visualizing, analyzing, and reporting information in support of the State Evaluation Process. This paper focuses on one of the examples a set of models developed in the Proactive Scenario Production, Evidence Collection, and Testing (ProSPECT) software that evaluates the status and nature of a state’s nuclear activities. The models use three distinct subject areas to perform this assessment: the presence of nuclearmore » activities, the consistency of those nuclear activities with national nuclear energy goals, and the geopolitical context in which those nuclear activities are taking place. As a proof-of-concept for the models, a crude case study was performed. The study, which attempted to evaluate the nuclear activities taking place in Syria prior to September 2007, yielded illustrative, yet inconclusive, results. Due to the inconclusive nature of the case study results, changes that may improve the model’s efficiency and accuracy are proposed.« less

Optimal Cytoplasmic Transport in Viral Infections

PubMed Central

D'Orsogna, Maria R.; Chou, Tom

2009-01-01

For many viruses, the ability to infect eukaryotic cells depends on their transport through the cytoplasm and across the nuclear membrane of the host cell. During this journey, viral contents are biochemically processed into complexes capable of both nuclear penetration and genomic integration. We develop a stochastic model of viral entry that incorporates all relevant aspects of transport, including convection along microtubules, biochemical conversion, degradation, and nuclear entry. Analysis of the nuclear infection probabilities in terms of the transport velocity, degradation, and biochemical conversion rates shows how certain values of key parameters can maximize the nuclear entry probability of the viral material. The existence of such “optimal” infection scenarios depends on the details of the biochemical conversion process and implies potentially counterintuitive effects in viral infection, suggesting new avenues for antiviral treatment. Such optimal parameter values provide a plausible transport-based explanation of the action of restriction factors and of experimentally observed optimal capsid stability. Finally, we propose a new interpretation of how genetic mutations unrelated to the mechanism of drug action may nonetheless confer novel types of overall drug resistance. PMID:20046829

The Economic Potential of Two Nuclear-Renewable Hybrid Energy Systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruth, Mark; Cutler, Dylan; Flores-Espino, Francisco

Tightly coupled nuclear-renewable hybrid energy systems (N-R HESs) are an option that can generate zero-carbon, dispatchable electricity and provide zero-carbon energy for industrial processes at a lower cost than alternatives. N-R HESs are defined as systems that are managed by a single entity and link a nuclear reactor that generates heat, a thermal power cycle for heat to electricity conversion, at least one renewable energy source, and an industrial process that uses thermal and/or electrical energy. This report provides results of an analysis of two N-R HES scenarios. The first is a Texas-synthetic gasoline scenario that includes four subsystems: amore » nuclear reactor, thermal power cycle, wind power plant, and synthetic gasoline production technology. The second is an Arizona-desalination scenario with its four subsystems a nuclear reactor, thermal power cycle, solar photovoltaics, and a desalination plant. The analysis focuses on the economics of the N-R HESs and how they compare to other options, including configurations without all the subsystems in each N-R HES and alternatives where the energy is provided by natural gas.« less

Dynamic high energy density plasma environments at the National Ignition Facility for nuclear science research

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cerjan, Ch J.; Bernstein, L.; Hopkins, L. Berzak

We present the generation of dynamic high energy density plasmas in the pico- to nano-second time domain at high-energy laser facilities affords unprecedented nuclear science research possibilities. At the National Ignition Facility (NIF), the primary goal of inertial confinement fusion research has led to the synergistic development of a unique high brightness neutron source, sophisticated nuclear diagnostic instrumentation, and versatile experimental platforms. These novel experimental capabilities provide a new path to investigate nuclear processes and structural effects in the time, mass and energy density domains relevant to astrophysical phenomena in a unique terrestrial environment. Some immediate applications include neutron capturemore » cross-section evaluation, fission fragment production, and ion energy loss measurement in electron-degenerate plasmas. More generally, the NIF conditions provide a singular environment to investigate the interplay of atomic and nuclear processes such as plasma screening effects upon thermonuclear reactivity. Lastly, achieving enhanced understanding of many of these effects will also significantly advance fusion energy research and challenge existing theoretical models.« less

Nuclear migration events throughout development

PubMed Central

Bone, Courtney R.

2016-01-01

ABSTRACT Moving the nucleus to a specific position within the cell is an important event during many cell and developmental processes. Several different molecular mechanisms exist to position nuclei in various cell types. In this Commentary, we review the recent progress made in elucidating mechanisms of nuclear migration in a variety of important developmental models. Genetic approaches to identify mutations that disrupt nuclear migration in yeast, filamentous fungi, Caenorhabditis elegans, Drosophila melanogaster and plants led to the identification of microtubule motors, as well as Sad1p, UNC-84 (SUN) domain and Klarsicht, ANC-1, Syne homology (KASH) domain proteins (LINC complex) that function to connect nuclei to the cytoskeleton. We focus on how these proteins and various mechanisms move nuclei during vertebrate development, including processes related to wound healing of fibroblasts, fertilization, developing myotubes and the developing central nervous system. We also describe how nuclear migration is involved in cells that migrate through constricted spaces. On the basis of these findings, it is becoming increasingly clear that defects in nuclear positioning are associated with human diseases, syndromes and disorders. PMID:27182060

Methods and apparatuses for the development of microstructured nuclear fuels

DOEpatents

Jarvinen, Gordon D [Los Alamos, NM; Carroll, David W [Los Alamos, NM; Devlin, David J [Santa Fe, NM

2009-04-21

Microstructured nuclear fuel adapted for nuclear power system use includes fissile material structures of micrometer-scale dimension dispersed in a matrix material. In one method of production, fissile material particles are processed in a chemical vapor deposition (CVD) fluidized-bed reactor including a gas inlet for providing controlled gas flow into a particle coating chamber, a lower bed hot zone region to contain powder, and an upper bed region to enable powder expansion. At least one pneumatic or electric vibrator is operationally coupled to the particle coating chamber for causing vibration of the particle coater to promote uniform powder coating within the particle coater during fuel processing. An exhaust associated with the particle coating chamber and can provide a port for placement and removal of particles and powder. During use of the fuel in a nuclear power reactor, fission products escape from the fissile material structures and come to rest in the matrix material. After a period of use in a nuclear power reactor and subsequent cooling, separation of the fissile material from the matrix containing the embedded fission products will provide an efficient partitioning of the bulk of the fissile material from the fission products. The fissile material can be reused by incorporating it into new microstructured fuel. The fission products and matrix material can be incorporated into a waste form for disposal or processed to separate valuable components from the fission products mixture.

The ``Folk Theorem'' on effective field theory: How does it fare in nuclear physics?

NASA Astrophysics Data System (ADS)

Rho, Mannque

2017-10-01

This is a brief history of what I consider as very important, some of which truly seminal, contributions made by young Korean nuclear theorists, mostly graduate students working on PhD thesis in 1990s and early 2000s, to nuclear effective field theory, nowadays heralded as the first-principle approach to nuclear physics. The theoretical framework employed is an effective field theory anchored on a single scale-invariant hidden local symmetric Lagrangian constructed in the spirit of Weinberg's "Folk Theorem" on effective field theory. The problems addressed are the high-precision calculations on the thermal np capture, the solar pp fusion process, the solar hep process — John Bahcall's challenge to nuclear theorists — and the quenching of g A in giant Gamow-Teller resonances and the whopping enhancement of first-forbidden beta transitions relevant in astrophysical processes. Extending adventurously the strategy to a wild uncharted domain in which a systematic implementation of the "theorem" is far from obvious, the same effective Lagrangian is applied to the structure of compact stars. A surprising, unexpected, result on the properties of massive stars, totally different from what has been obtained up to day in the literature, is predicted, such as the precocious onset of conformal sound velocity together with a hint for the possible emergence in dense matter of hidden symmetries such as scale symmetry and hidden local symmetry.

Nuclear-Renewable Hybrid Energy System Market Analysis Plans

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruth, Mark

2016-06-09

This presentation describes nuclear-renewable hybrid energy systems (N-R HESs), states their potential benefits, provides figures for the four tightly coupled N-R HESs that NREL is currently analyzing, and outlines the analysis process that is underway.

1987 Nuclear Science Symposium, 34th, and 1987 Symposium on Nuclear Power Systems, 19th, San Francisco, CA, Oct. 21-23, 1987, Proceedings

NASA Astrophysics Data System (ADS)

Armantrout, Guy A.

1988-02-01

The present conference consideres topics in radiation detectors, advanced electronic circuits, data acquisition systems, radiation detector systems, high-energy and nuclear physics radiation detection, spaceborne instrumentation, health physics and environmental radiation detection, nuclear medicine, nuclear well logging, and nuclear reactor instrumentation. Attention is given to the response of scintillators to heavy ions, phonon-mediated particle detection, ballistic deficits in pulse-shaping amplifiers, fast analog ICs for particle physics, logic cell arrays, the CERN host interface, high performance data buses, a novel scintillating glass for high-energy physics applications, background events in microchannel plates, a tritium accelerator mass spectrometer, a novel positron tomograph, advancements in PET, cylindrical positron tomography, nuclear techniques in subsurface geology, REE borehole neutron activation, and a continuous tritium monitor for aqueous process streams.

Processing and analysis of commercial satellite image data of the nuclear accident near Chernobyl, U.S.S.R.

USGS Publications Warehouse

Sadowski, Franklin G.; Covington, Steven J.

1987-01-01

Advanced digital processing techniques were applied to Landsat-5 Thematic Mapper (TM) data and SPOT highresolution visible (HRV) panchromatic data to maximize the utility of images of a nuclear powerplant emergency at Chernobyl in the Soviet Ukraine. The images demonstrate the unique interpretive capabilities provided by the numerous spectral bands of the Thematic Mapper and the high spatial resolution of the SPOT HRV sensor.

Decommissioning the Fuel Process Building, a Shift in Paradigm for Terminating Safeguards on Process Holdup

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ivan R. Thomas

INMM Abstract 51st Annual Meeting Decommissioning the Fuel Process Building, a Shift in Paradigm for Terminating Safeguards on Process Holdup The Fuel Process Building at the Idaho Nuclear Technology and Engineering Center (INTEC) is being decommissioned after nearly four decades of recovering high enriched uranium from various government owned spent nuclear fuels. The separations process began with fuel dissolution in one of multiple head-ends, followed by three cycles of uranium solvent extraction, and ending with denitration of uranyl nitrate product. The entire process was very complex, and the associated equipment formed an extensive maze of vessels, pumps, piping, and instrumentationmore » within several layers of operating corridors and process cells. Despite formal flushing and cleanout procedures, an accurate accounting for the residual uranium held up in process equipment over extended years of operation, presented a daunting safeguards challenge. Upon cessation of domestic reprocessing, the holdup remained inaccessible and was exempt from measurement during ensuing physical inventories. In decommissioning the Fuel Process Building, the Idaho Cleanup Project, which operates the INTEC, deviated from the established requirements that all nuclear material holdup be measured and credited to the accountability books and that all nuclear materials, except attractiveness level E residual holdup, be transferred to another facility. Instead, the decommissioning involved grouting the process equipment in place, rather than measuring and removing the contained holdup for subsequent transfer. The grouting made the potentially attractiveness level C and D holdup even more inaccessible, thereby effectually converting the holdup to attractiveness level E and allowing for termination of safeguards controls. Prior to grouting the facility, the residual holdup was estimated by limited sampling and destructive analysis of solutions in process lines and by acceptable knowledge based upon the separations process, plant layout, and operating history. The use of engineering estimates, in lieu of approved measurement methods, was justified by the estimated small quantity of holdup remaining, the infeasibility of measuring the holdup in a highly radioactive background, and the perceived hazards to personnel. The alternate approach to quantifying and terminating safeguards on process holdup was approved by deviation.« less

Progress on China nuclear data processing code system

NASA Astrophysics Data System (ADS)

Liu, Ping; Wu, Xiaofei; Ge, Zhigang; Li, Songyang; Wu, Haicheng; Wen, Lili; Wang, Wenming; Zhang, Huanyu

2017-09-01

China is developing the nuclear data processing code Ruler, which can be used for producing multi-group cross sections and related quantities from evaluated nuclear data in the ENDF format [1]. The Ruler includes modules for reconstructing cross sections in all energy range, generating Doppler-broadened cross sections for given temperature, producing effective self-shielded cross sections in unresolved energy range, calculating scattering cross sections in thermal energy range, generating group cross sections and matrices, preparing WIMS-D format data files for the reactor physics code WIMS-D [2]. Programming language of the Ruler is Fortran-90. The Ruler is tested for 32-bit computers with Windows-XP and Linux operating systems. The verification of Ruler has been performed by comparison with calculation results obtained by the NJOY99 [3] processing code. The validation of Ruler has been performed by using WIMSD5B code.

LANDSAT-4 image data quality analysis for energy related applications. [nuclear power plant sites

NASA Technical Reports Server (NTRS)

Wukelic, G. E. (Principal Investigator)

1983-01-01

No useable LANDSAT 4 TM data were obtained for the Hanford site in the Columbia Plateau region, but TM simulator data for a Virginia Electric Company nuclear power plant was used to test image processing algorithms. Principal component analyses of this data set clearly indicated that thermal plumes in surface waters used for reactor cooling would be discrenible. Image processing and analysis programs were successfully testing using the 7 band Arkansas test scene and preliminary analysis of TM data for the Savanah River Plant shows that current interactive, image enhancement, analysis and integration techniques can be effectively used for LANDSAT 4 data. Thermal band data appear adequate for gross estimates of thermal changes occurring near operating nuclear facilities especially in surface water bodies being used for reactor cooling purposes. Additional image processing software was written and tested which provides for more rapid and effective analysis of the 7 band TM data.

TN International and ITS operational feedback regarding the decommissioning of obsolete casks dedicated to the transport and/or storage of nuclear raw materials, fuel and used fuel

DOE Office of Scientific and Technical Information (OSTI.GOV)

Blachet, L.; Bimet, F.; Rennesson, N.

2008-07-01

Within the AREVA group, TN International is a major actor regarding the design of casks and transportation for the nuclear cycle. In the early 2005, TN International has started the project of decommissioning some of its own equipment and was hence the first company ever in the AREVA Group to implement this new approach. In order to do so, TN International has based this project by taking into account the AREVA Sustainable Development Charter, the French regulatory framework, the ANDRA (Agence Nationale pour la Gestion des Dechets Radioactifs - National Agency for the radioactive waste management) requirements and has deployedmore » a step by step methodology such as radiological characterization following a logical route. The aim was to define a standardized process with optimized solutions regarding the diversity of the cask's fleet. As a general matter, decommissioning of nuclear casks is a brand new field as the nuclear field is more familiar with the dismantling of nuclear facilities and/or nuclear power plant. Nevertheless existing workshops, maintenance facilities, measurements equipments and techniques have been exploited and adapted by TN International in order to turn an ambitious project into a permanent and cost-effective activity. The decommissioning of the nuclear casks implemented by TN International regarding its own needs and the French regulatory framework is formalized by several processes and is materialized for instance by the final disposal of casks as they are or in ISO container packed with cut-off casks and big bags filled with crushed internal cask equipments, etc. The first part of this paper aims to describe the history of the project that started with a specific environmental analysis which took into account the values of AREVA as regards the Sustainable Development principles that were at the time and are still a topic of current concern in the world. The second part will deal with the definition, the design and the implementation of the decommissioning processes and the applied techniques. The third part will present a two years operational feedback. The last part will introduce new processes which are currently under investigation and will put into light that decommissioning of nuclear casks is a continuous activity that is in perpetual mutation. (authors)« less

Breach of the nuclear lamina during assembly of herpes simplex viruses.

PubMed

Morrison, Lynda A; DeLassus, Gregory S

2011-01-01

Beneath the inner nuclear membrane lies the dense meshwork of the nuclear lamina, which provides structural support for the nuclear envelope and serves as an important organizing center for a number of nuclear and cytoplasmic constituents and processes. Herpesviruses have a significant and wide-ranging impact on human health, and their capacity to replicate and cause disease includes events that occur in the host cell nucleus. Herpesviruses begin assembly of progeny virus in the nuclei of infected cells and their capsids must escape the confines of the nucleus by budding through the inner nuclear membrane (INM) to proceed with later stages of virion assembly and egress. Access of viral capsids to the INM thus necessitates disruption of the dense nuclear lamina layer. We review herpesvirus effects on the nuclear lamina and in particular the roles of the herpes simplex virus-encoded nuclear envelope complex and viral kinases on lamin phosphorylation, dissociation, and nucleocapsid envelopment at the INM.

Analysis of the transient response of nuclear spins in GaAs with/without nuclear magnetic resonance

NASA Astrophysics Data System (ADS)

Rasly, Mahmoud; Lin, Zhichao; Yamamoto, Masafumi; Uemura, Tetsuya

2016-05-01

As an alternative to studying the steady-state responses of nuclear spins in solid state systems, working within a transient-state framework can reveal interesting phenomena. The response of nuclear spins in GaAs to a changing magnetic field was analyzed based on the time evolution of nuclear spin temperature. Simulation results well reproduced our experimental results for the transient oblique Hanle signals observed in an all-electrical spin injection device. The analysis showed that the so called dynamic nuclear polarization can be treated as a cooling tool for the nuclear spins: It works as a provider to exchange spin angular momentum between polarized electron spins and nuclear spins through the hyperfine interaction, leading to an increase in the nuclear polarization. In addition, a time-delay of the nuclear spin temperature with a fast sweep of the external magnetic field produces a possible transient state for the nuclear spin polarization. On the other hand, the nuclear magnetic resonance acts as a heating tool for a nuclear spin system. This causes the nuclear spin temperature to jump to infinity: i.e., the average nuclear spins along with the nuclear field vanish at resonant fields of 75As, 69Ga and 71Ga, showing an interesting step-dip structure in the oblique Hanle signals. These analyses provide a quantitative understanding of nuclear spin dynamics in semiconductors for application in future computation processing.

Nuclear energy: salvation or suicide. [Contains glossary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collins, C.C.

A collection of 700 editorials and feature articles collected from 125 US newspapers addresses the dominant areas of concern about nuclear power: plant safety, radioactive wastes, proliferation, and cost. The editorial debates present the pros and cons of Three Mile Island and other accidents, ocean dumping, evacuation plans, radioactive waste transport and storage, nuclear fuel processing, the Karen Silkwood case, and breeder reactors. The appendix raises the question of the future for fission and the possibility of nuclear fusion as an alternative. There is a subject index and a glossary of basic terms.

Review of nuclear pharmacy practice in hospitals

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kawada, T.K.; Tubis, M.; Ebenkamp, T.

1982-02-01

An operational profile for nuclear pharmacy practice is presented, and the technical and professional role of nuclear pharmacists is reviewed. Key aspects of nuclear pharmacy practice in hospitals discussed are the basic facilities and equipment for the preparation, quality control, and distribution of radioactive drug products. Standards for receiving, storing, and processing radioactive material are described. The elements of a radiopharmaceutical quality assurance program, including the working procedures, documentation systems, data analysis, and specific control tests, are presented. Details of dose preparation and administration and systems of inventory control for radioactive products are outlined.

Systems and methods for processing irradiation targets through a nuclear reactor

DOEpatents

Dayal, Yogeshwar; Saito, Earl F.; Berger, John F.; Brittingham, Martin W.; Morales, Stephen K.; Hare, Jeffrey M.

2016-05-03

Apparatuses and methods produce radioisotopes in instrumentation tubes of operating commercial nuclear reactors. Irradiation targets may be inserted and removed from instrumentation tubes during operation and converted to radioisotopes otherwise unavailable during operation of commercial nuclear reactors. Example apparatuses may continuously insert, remove, and store irradiation targets to be converted to useable radioisotopes or other desired materials at several different origin and termination points accessible outside an access barrier such as a containment building, drywell wall, or other access restriction preventing access to instrumentation tubes during operation of the nuclear plant.

Effect of geometrical configuration of radioactive sources on radiation intensity in beta-voltaic nuclear battery system: A preliminary result

DOE Office of Scientific and Technical Information (OSTI.GOV)

Basar, Khairul, E-mail: khbasar@fi.itb.ac.id; Riupassa, Robi D., E-mail: khbasar@fi.itb.ac.id; Bachtiar, Reza, E-mail: khbasar@fi.itb.ac.id

2014-01-01

It is known that one main problem in the application of beta-voltaic nuclear battery system is its low efficiency. The efficiency of the beta-voltaic nuclear battery system mainly depends on three aspects: source of radioactive radiation, interface between materials in the system and process of converting electron-hole pair to electric current in the semiconductor material. In this work, we show the effect of geometrical configuration of radioactive sources on radiation intensity of beta-voltaic nuclear battery system.

Plasma filtering techniques for nuclear waste remediation.

PubMed

Gueroult, Renaud; Hobbs, David T; Fisch, Nathaniel J

2015-10-30

Nuclear waste cleanup is challenged by the handling of feed stocks that are both unknown and complex. Plasma filtering, operating on dissociated elements, offers advantages over chemical methods in processing such wastes. The costs incurred by plasma mass filtering for nuclear waste pretreatment, before ultimate disposal, are similar to those for chemical pretreatment. However, significant savings might be achieved in minimizing the waste mass. This advantage may be realized over a large range of chemical waste compositions, thereby addressing the heterogeneity of legacy nuclear waste. Copyright © 2015 Elsevier B.V. All rights reserved.

Modulation of ROS levels in fibroblasts by altering mitochondria regulates the process of wound healing.

PubMed

Janda, Jaroslav; Nfonsam, Valentine; Calienes, Fernanda; Sligh, James E; Jandova, Jana

2016-05-01

Mitochondria are the major source of reactive oxygen species (ROS) in fibroblasts which are thought to be crucial regulators of wound healing with a potential to affect the expression of nuclear genes involved in this process. ROS generated by mitochondria are involved in all stages of tissue repair process but the regulation of ROS-generating system in fibroblasts still remains poorly understood. The purpose of this study was to better understand molecular mechanisms of how the regulation of ROS levels generated by mitochondria may influence the process of wound repair. Cybrid model system of mtDNA variations was used to study the functional consequences of altered ROS levels on wound healing responses in a uniform nuclear background of cultured ρ(0) fibroblasts. Mitochondrial ROS in cybrids were modulated by antioxidants that quench ROS to examine their ability to close the wound. Real-time PCR arrays were used to investigate whether ROS generated by specific mtDNA variants have the ability to alter expression of some key nuclear-encoded genes central to the wound healing response and oxidative stress. Our data suggest levels of mitochondrial ROS affect expression of some nuclear encoded genes central to wound healing response and oxidative stress and modulation of mitochondrial ROS by antioxidants positively affects in vitro process of wound closure. Thus, regulation of mitochondrial ROS-generating system in fibroblasts can be used as effective natural redox-based strategy to help treat non-healing wounds.

On some control problems of dynamic of reactor

NASA Astrophysics Data System (ADS)

Baskakov, A. V.; Volkov, N. P.

2017-12-01

The paper analyzes controllability of the transient processes in some problems of nuclear reactor dynamics. In this case, the mathematical model of nuclear reactor dynamics is described by a system of integro-differential equations consisting of the non-stationary anisotropic multi-velocity kinetic equation of neutron transport and the balance equation of delayed neutrons. The paper defines the formulation of the linear problem on control of transient processes in nuclear reactors with application of spatially distributed actions on internal neutron sources, and the formulation of the nonlinear problems on control of transient processes with application of spatially distributed actions on the neutron absorption coefficient and the neutron scattering indicatrix. The required control actions depend on the spatial and velocity coordinates. The theorems on existence and uniqueness of these control actions are proved in the paper. To do this, the control problems mentioned above are reduced to equivalent systems of integral equations. Existence and uniqueness of the solution for this system of integral equations is proved by the method of successive approximations, which makes it possible to construct an iterative scheme for numerical analyses of transient processes in a given nuclear reactor with application of the developed mathematical model. Sufficient conditions for controllability of transient processes are also obtained. In conclusion, a connection is made between the control problems and the observation problems, which, by to the given information, allow us to reconstruct either the function of internal neutron sources, or the neutron absorption coefficient, or the neutron scattering indicatrix....

Brief overview of the long-lived radionuclide separation processes developed in france in connection with the spin program

NASA Astrophysics Data System (ADS)

Madic, Charles; Bourges, Jacques; Dozol, Jean-François

1995-09-01

To reduce the long-term potential hazards associated with the management of nuclear wastes generated by nuclear fuel reprocessing, one alternative is the transmutation of long-lived radionuclides into short-lived radionuclides by nuclear means (P & T strategy). In this context, according to the law passed by the French Parliament on 30 December 1991, the CEA launched the SPIN program for the design of long-lived radionuclide separation and nuclear incineration processes. The research in progress to define separation processes focused mainly on the minor actinides (neptunium, americium and curium) and some fission products, like cesium and technetium. To separate these long-lived radionuclides, two strategies were developed. The first involves research on new operating conditions for improving the PUREX fuel reprocessing technology. This approach concerns the elements neptunium and technetium (iodine and zirconium can also be considered). The second strategy involves the design of new processes; DIAMEX for the co-extraction of minor actinides from the high-level liquid waste leaving the PUREX process, An(III)/Ln(III) separation using tripyridyltriazine derivatives or picolinamide extracting agents; SESAME for the selective separation of americium after its oxidation to Am(IV) or Am(VI) in the presence of a heteropolytungstate ligand, and Cs extraction using a new class of extracting agents, calixarenes, which exhibit exceptional Cs separation properties, especially in the presence of sodium ion. This lecture focuses on the latest achievements in these research areas.

Late Maturation Steps Preceding Selective Nuclear Export and Egress of Progeny Parvovirus

PubMed Central

Wolfisberg, Raphael; Kempf, Christoph

2016-01-01

ABSTRACT Although the mechanism is not well understood, growing evidence indicates that the nonenveloped parvovirus minute virus of mice (MVM) may actively egress before passive release through cell lysis. We have dissected the late maturation steps of the intranuclear progeny with the aims of confirming the existence of active prelytic egress and identifying critical capsid rearrangements required to initiate the process. By performing anion-exchange chromatography (AEX), we separated intranuclear progeny particles by their net surface charges. Apart from empty capsids (EC), two distinct populations of full capsids (FC) arose in the nuclei of infected cells. The earliest population of FC to appear was infectious but, like EC, could not be actively exported from the nucleus. Further maturation of this early population, involving the phosphorylation of surface residues, gave rise to a second, late population with nuclear export potential. While capsid surface phosphorylation was strictly associated with nuclear export capacity, mutational analysis revealed that the phosphoserine-rich N terminus of VP2 (N-VP2) was dispensable, although it contributed to passive release. The reverse situation was observed for the incoming particles, which were dephosphorylated in the endosomes. Our results confirm the existence of active prelytic egress and reveal a late phosphorylation event occurring in the nucleus as a selective factor for initiating the process. IMPORTANCE In general, the process of egress of enveloped viruses is active and involves host cell membranes. However, the release of nonenveloped viruses seems to rely more on cell lysis. At least for some nonenveloped viruses, an active process before passive release by cell lysis has been reported, although the underlying mechanism remains poorly understood. By using the nonenveloped model parvovirus minute virus of mice, we could confirm the existence of an active process of nuclear export and further characterize the associated capsid maturation steps. Following DNA packaging in the nucleus, capsids required further modifications, involving the phosphorylation of surface residues, to acquire nuclear export potential. Inversely, those surface residues were dephosphorylated on entering capsids. These spatially controlled phosphorylation-dephosphorylation events concurred with the nuclear export-import potential required to complete the infectious cycle. PMID:27009963

Late Maturation Steps Preceding Selective Nuclear Export and Egress of Progeny Parvovirus.

PubMed

Wolfisberg, Raphael; Kempf, Christoph; Ros, Carlos

2016-06-01

Although the mechanism is not well understood, growing evidence indicates that the nonenveloped parvovirus minute virus of mice (MVM) may actively egress before passive release through cell lysis. We have dissected the late maturation steps of the intranuclear progeny with the aims of confirming the existence of active prelytic egress and identifying critical capsid rearrangements required to initiate the process. By performing anion-exchange chromatography (AEX), we separated intranuclear progeny particles by their net surface charges. Apart from empty capsids (EC), two distinct populations of full capsids (FC) arose in the nuclei of infected cells. The earliest population of FC to appear was infectious but, like EC, could not be actively exported from the nucleus. Further maturation of this early population, involving the phosphorylation of surface residues, gave rise to a second, late population with nuclear export potential. While capsid surface phosphorylation was strictly associated with nuclear export capacity, mutational analysis revealed that the phosphoserine-rich N terminus of VP2 (N-VP2) was dispensable, although it contributed to passive release. The reverse situation was observed for the incoming particles, which were dephosphorylated in the endosomes. Our results confirm the existence of active prelytic egress and reveal a late phosphorylation event occurring in the nucleus as a selective factor for initiating the process. In general, the process of egress of enveloped viruses is active and involves host cell membranes. However, the release of nonenveloped viruses seems to rely more on cell lysis. At least for some nonenveloped viruses, an active process before passive release by cell lysis has been reported, although the underlying mechanism remains poorly understood. By using the nonenveloped model parvovirus minute virus of mice, we could confirm the existence of an active process of nuclear export and further characterize the associated capsid maturation steps. Following DNA packaging in the nucleus, capsids required further modifications, involving the phosphorylation of surface residues, to acquire nuclear export potential. Inversely, those surface residues were dephosphorylated on entering capsids. These spatially controlled phosphorylation-dephosphorylation events concurred with the nuclear export-import potential required to complete the infectious cycle. Copyright © 2016, American Society for Microbiology. All Rights Reserved.

Exploring Students' Ideas About Risks and Benefits of Nuclear Power Using Risk Perception Theories

NASA Astrophysics Data System (ADS)

Kılınç, Ahmet; Boyes, Edward; Stanisstreet, Martin

2013-06-01

Due to increased energy demand, Turkey is continuing to explore the possibilities of introducing nuclear power. Gaining acceptance from local populations, however, may be problematic because nuclear power has a negative image and risk perceptions are complicated by a range of psychological and cultural factors. In this study, we explore the views about nuclear power of school students from three locations in Turkey, two of which have been proposed as sites suitable for nuclear power plants. About half of the student cohort believed that nuclear power can supply continuous and sufficient electricity, but approximately three quarters thought that nuclear power stations could harm organisms, including humans, living nearby. Rather few students realized that adoption of nuclear power would help to reduce global warming and thereby limit climate change; indeed, three quarters thought that nuclear power would make global warming worse. There was a tendency for more students from the location most likely to have a nuclear power plant to believe negative characteristics of nuclear power, and for fewer students to believe positive characteristics. Exploration of the possible nuclear power programmes by Turkey offers an educational opportunity to understand the risk perceptions of students that affect their decision-making processes.

CDKL5 influences RNA splicing activity by its association to the nuclear speckle molecular machinery.

PubMed

Ricciardi, Sara; Kilstrup-Nielsen, Charlotte; Bienvenu, Thierry; Jacquette, Aurélia; Landsberger, Nicoletta; Broccoli, Vania

2009-12-01

Mutations in the human X-linked cyclin-dependent kinase-like 5 (CDKL5) gene have been shown to cause severe neurodevelopmental disorders including infantile spasms, encephalopathy, West-syndrome and an early-onset variant of Rett syndrome. CDKL5 is a serine/threonine kinase whose involvement in Rett syndrome can be inferred by its ability to directly bind and mediate phosphorylation of MeCP2. However, it remains to be elucidated how CDKL5 exerts its function. Here, we report that CDKL5 localizes to specific nuclear foci referred to as nuclear speckles in both cell lines and tissues. These sub-nuclear structures are traditionally considered as storage/modification sites of pre-mRNA splicing factors. Interestingly, we provide evidence that CDKL5 regulates the dynamic behaviour of nuclear speckles. Indeed, CDKL5 overexpression leads to nuclear speckle disassembly, and this event is strictly dependent on its kinase activity. Conversely, its down-regulation affects nuclear speckle morphology leading to abnormally large and uneven speckles. Similar results were obtained for primary adult fibroblasts isolated from CDKL5-mutated patients. Altogether, these findings indicate that CDKL5 controls nuclear speckle morphology probably by regulating the phosphorylation state of splicing regulatory proteins. Nuclear speckles are dynamic sites that can continuously supply splicing factors to active transcription sites, where splicing occurs. Notably, we proved that CDKL5 influences alternative splicing, at least as proved in heterologous minigene assays. In conclusion, we provide evidence that CDKL5 is involved indirectly in pre-mRNA processing, by controlling splicing factor dynamics. These findings identify a biological process whose disregulation might affect neuronal maturation and activity in CDKL5-related disorders.

SPECTROSCOPIC ONLINE MONITORING FOR PROCESS CONTROL AND SAFEGUARDING OF RADIOCHEMICAL STREAMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bryan, Samuel A.; Levitskaia, Tatiana G.

2013-09-29

There is a renewed interest worldwide to promote the use of nuclear power and close the nuclear fuel cycle. The long term successful use of nuclear power is critically dependent upon adequate and safe processing and disposition of the used nuclear fuel. Liquid-liquid extraction is a separation technique commonly employed for the processing of the dissolved used nuclear fuel. The instrumentation used to monitor these processes must be robust, require little or no maintenance, and be able to withstand harsh environments such as high radiation fields and aggressive chemical matrices. This paper summarizes application of the absorption and vibrational spectroscopicmore » techniques supplemented by physicochemical measurements for radiochemical process monitoring. In this context, our team experimentally assessed the potential of Raman and spectrophotometric techniques for online real-time monitoring of the U(VI)/nitrate ion/nitric acid and Pu(IV)/Np(V)/Nd(III), respectively, in solutions relevant to spent fuel reprocessing. These techniques demonstrate robust performance in the repetitive batch measurements of each analyte in a wide concentration range using simulant and commercial dissolved spent fuel solutions. Spectroscopic measurements served as training sets for the multivariate data analysis to obtain partial least squares predictive models, which were validated using on-line centrifugal contactor extraction tests. Satisfactory prediction of the analytes concentrations in these preliminary experiments warrants further development of the spectroscopy-based methods for radiochemical process control and safeguarding. Additionally, the ability to identify material intentionally diverted from a liquid-liquid extraction contactor system was successfully tested using on-line process monitoring as a means to detect the amount of material diverted. A chemical diversion and detection from a liquid-liquid extraction scheme was demonstrated using a centrifugal contactor system operating with the simulant PUREX extraction system of Nd(NO3)3/nitric acid aqueous phase and TBP/n-dodecane organic phase. During a continuous extraction experiment, a portion of the feed from a counter-current extraction system was diverted while the spectroscopic on-line process monitoring system was simultaneously measuring the feed, raffinate and organic products streams. The amount observed to be diverted by on-line spectroscopic process monitoring was in excellent agreement with values based from the known mass of sample directly taken (diverted) from system feed solution.« less

Nuclear Forensics: A Methodology Applicable to Nuclear Security and to Non-Proliferation

NASA Astrophysics Data System (ADS)

Mayer, K.; Wallenius, M.; Lützenkirchen, K.; Galy, J.; Varga, Z.; Erdmann, N.; Buda, R.; Kratz, J.-V.; Trautmann, N.; Fifield, K.

2011-09-01

Nuclear Security aims at the prevention and detection of and response to, theft, sabotage, unauthorized access, illegal transfer or other malicious acts involving nuclear material. Nuclear Forensics is a key element of nuclear security. Nuclear Forensics is defined as a methodology that aims at re-establishing the history of nuclear material of unknown origin. It is based on indicators that arise from known relationships between material characteristics and process history. Thus, nuclear forensics analysis includes the characterization of the material and correlation with production history. To this end, we can make use of parameters such as the isotopic composition of the nuclear material and accompanying elements, chemical impurities, macroscopic appearance and microstructure of the material. In the present paper, we discuss the opportunities for attribution of nuclear material offered by nuclear forensics as well as its limitations. Particular attention will be given to the role of nuclear reactions. Such reactions include the radioactive decay of the nuclear material, but also reactions with neutrons. When uranium (of natural composition) is exposed to neutrons, plutonium is formed, as well as 236U. We will illustrate the methodology using the example of a piece of uranium metal that dates back to the German nuclear program in the 1940's. A combination of different analytical techniques and model calculations enables a nuclear forensics interpretation, thus correlating the material characteristics with the production history.

Summary Report of the Workshop on The Experimental Nuclear Reaction Data Database

DOE Office of Scientific and Technical Information (OSTI.GOV)

Semkova, V.; Pritychenko, B.

2014-12-01

The Workshop on the Experimental Nuclear Reaction Data Database (EXFOR) was held at IAEA Headquarters in Vienna from 6 to 10 October 2014. The workshop was organized to discuss various aspects of the EXFOR compilation process including compilation rules, different techniques for nuclear reaction data measurements, software developments, etc. A summary of the presentations and discussions that took place during the workshop is reported here.

Guidelines for direct radionuclide cystography in children.

PubMed

Fettich, Jure; Colarinha, Paula; Fischer, Sibylle; Frökier, Jörgen; Gordon, Isky; Hahn, Klaus; Kabasakal, Levent; Mann, Mike; Mitjavila, Mercedes; Olivier, Pierre; Piepsz, Amy; Porn, Ute; Roca, Isabel; Sixt, Rune; van Velzen, Jeannette

2003-05-01

These guidelines, which summarise the views of the Paediatric Committee of the European Association of Nuclear Medicine, provide a framework which may prove helpful to nuclear medicine teams in daily practice. They contain information on the indications, acquisition, processing and interpretation of direct radioisotope cystography in children. The guidelines should be taken in the context of "good practice" and any local/national rules which apply to nuclear medicine examinations.

Integrated Response Time Evaluation Methodology for the Nuclear Safety Instrumentation System

NASA Astrophysics Data System (ADS)

Lee, Chang Jae; Yun, Jae Hee

2017-06-01

Safety analysis for a nuclear power plant establishes not only an analytical limit (AL) in terms of a measured or calculated variable but also an analytical response time (ART) required to complete protective action after the AL is reached. If the two constraints are met, the safety limit selected to maintain the integrity of physical barriers used for preventing uncontrolled radioactivity release will not be exceeded during anticipated operational occurrences and postulated accidents. Setpoint determination methodologies have actively been developed to ensure that the protective action is initiated before the process conditions reach the AL. However, regarding the ART for a nuclear safety instrumentation system, an integrated evaluation methodology considering the whole design process has not been systematically studied. In order to assure the safety of nuclear power plants, this paper proposes a systematic and integrated response time evaluation methodology that covers safety analyses, system designs, response time analyses, and response time tests. This methodology is applied to safety instrumentation systems for the advanced power reactor 1400 and the optimized power reactor 1000 nuclear power plants in South Korea. The quantitative evaluation results are provided herein. The evaluation results using the proposed methodology demonstrate that the nuclear safety instrumentation systems fully satisfy corresponding requirements of the ART.

A Review of Flow Analysis Methods for Determination of Radionuclides in Nuclear Wastes and Nuclear Reactor Coolants

DOE PAGES

Trojanowicz, Marek; Kolacinska, Kamila; Grate, Jay W.

2018-02-13

Here, the safety and security of nuclear power plant operations depend on the application of the most appropriate techniques and methods of chemical analysis, where modern flow analysis methods prevail. Nevertheless, the current status of the development of these methods is more limited than it might be expected based on their genuine advantages. The main aim of this paper is to review the automated flow analysis procedures developed with various detection methods for the nuclear energy industry. The flow analysis methods for the determination of radionuclides, that have been reported to date, are primarily focused on their environmental applications. Themore » benefits of the application of flow methods in both monitoring of the nuclear wastes and process analysis of the primary circuit coolants of light water nuclear reactors will also be discussed. The application of either continuous flow methods (CFA) or injection methods (FIA, SIA) of the flow analysis with the β–radiometric detection shortens the analysis time and improves the precision of determination due to mechanization of certain time-consuming operations of the sample processing. Compared to the radiometric detection, the mass spectrometry (MS) detection enables one to perform multicomponent analyses as well as the determination of transuranic isotopes with much better limits of detection.« less

A Review of Flow Analysis Methods for Determination of Radionuclides in Nuclear Wastes and Nuclear Reactor Coolants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Trojanowicz, Marek; Kolacinska, Kamila; Grate, Jay W.

Here, the safety and security of nuclear power plant operations depend on the application of the most appropriate techniques and methods of chemical analysis, where modern flow analysis methods prevail. Nevertheless, the current status of the development of these methods is more limited than it might be expected based on their genuine advantages. The main aim of this paper is to review the automated flow analysis procedures developed with various detection methods for the nuclear energy industry. The flow analysis methods for the determination of radionuclides, that have been reported to date, are primarily focused on their environmental applications. Themore » benefits of the application of flow methods in both monitoring of the nuclear wastes and process analysis of the primary circuit coolants of light water nuclear reactors will also be discussed. The application of either continuous flow methods (CFA) or injection methods (FIA, SIA) of the flow analysis with the β–radiometric detection shortens the analysis time and improves the precision of determination due to mechanization of certain time-consuming operations of the sample processing. Compared to the radiometric detection, the mass spectrometry (MS) detection enables one to perform multicomponent analyses as well as the determination of transuranic isotopes with much better limits of detection.« less

A review of flow analysis methods for determination of radionuclides in nuclear wastes and nuclear reactor coolants.

PubMed

Trojanowicz, Marek; Kołacińska, Kamila; Grate, Jay W

2018-06-01

The safety and security of nuclear power plant operations depend on the application of the most appropriate techniques and methods of chemical analysis, where modern flow analysis methods prevail. Nevertheless, the current status of the development of these methods is more limited than it might be expected based on their genuine advantages. The main aim of this paper is to review the automated flow analysis procedures developed with various detection methods for the nuclear energy industry. The flow analysis methods for the determination of radionuclides, that have been reported to date, are primarily focused on their environmental applications. The benefits of the application of flow methods in both monitoring of the nuclear wastes and process analysis of the primary circuit coolants of light water nuclear reactors will also be discussed. The application of either continuous flow methods (CFA) or injection methods (FIA, SIA) of the flow analysis with the β-radiometric detection shortens the analysis time and improves the precision of determination due to mechanization of certain time-consuming operations of the sample processing. Compared to the radiometric detection, the mass spectrometry (MS) detection enables one to perform multicomponent analyses as well as the determination of transuranic isotopes with much better limits of detection. Copyright © 2018 Elsevier B.V. All rights reserved.

Analysis of Spatial Point Patterns in Nuclear Biology

PubMed Central

Weston, David J.; Adams, Niall M.; Russell, Richard A.; Stephens, David A.; Freemont, Paul S.

2012-01-01

There is considerable interest in cell biology in determining whether, and to what extent, the spatial arrangement of nuclear objects affects nuclear function. A common approach to address this issue involves analyzing a collection of images produced using some form of fluorescence microscopy. We assume that these images have been successfully pre-processed and a spatial point pattern representation of the objects of interest within the nuclear boundary is available. Typically in these scenarios, the number of objects per nucleus is low, which has consequences on the ability of standard analysis procedures to demonstrate the existence of spatial preference in the pattern. There are broadly two common approaches to look for structure in these spatial point patterns. First a spatial point pattern for each image is analyzed individually, or second a simple normalization is performed and the patterns are aggregated. In this paper we demonstrate using synthetic spatial point patterns drawn from predefined point processes how difficult it is to distinguish a pattern from complete spatial randomness using these techniques and hence how easy it is to miss interesting spatial preferences in the arrangement of nuclear objects. The impact of this problem is also illustrated on data related to the configuration of PML nuclear bodies in mammalian fibroblast cells. PMID:22615822

Application of Radiation Chemistry to Some Selected Technological Issues Related to the Development of Nuclear Energy.

PubMed

Bobrowski, Krzysztof; Skotnicki, Konrad; Szreder, Tomasz

2016-10-01

The most important contributions of radiation chemistry to some selected technological issues related to water-cooled reactors, reprocessing of spent nuclear fuel and high-level radioactive wastes, and fuel evolution during final radioactive waste disposal are highlighted. Chemical reactions occurring at the operating temperatures and pressures of reactors and involving primary transients and stable products from water radiolysis are presented and discussed in terms of the kinetic parameters and radiation chemical yields. The knowledge of these parameters is essential since they serve as input data to the models of water radiolysis in the primary loop of light water reactors and super critical water reactors. Selected features of water radiolysis in heterogeneous systems, such as aqueous nanoparticle suspensions and slurries, ceramic oxides surfaces, nanoporous, and cement-based materials, are discussed. They are of particular concern in the primary cooling loops in nuclear reactors and long-term storage of nuclear waste in geological repositories. This also includes radiation-induced processes related to corrosion of cladding materials and copper-coated iron canisters, dissolution of spent nuclear fuel, and changes of bentonite clays properties. Radiation-induced processes affecting stability of solvents and solvent extraction ligands as well oxidation states of actinide metal ions during recycling of the spent nuclear fuel are also briefly summarized.

Ways to Initiate a Nuclear Reaction in Solid Environments

NASA Astrophysics Data System (ADS)

Storms, E. K.

2001-03-01

Although conventional science ignores and rejects it, a new phenomenon has been reported in hundreds of studies from laboratories throughout the world. The phenomenon involves initiating nuclear reactions within special solid structures without applying high energy, as is the usual method. In particular, fusion of ^2H to form He, ^3H, and significant energy has been duplicated in several laboratories in Japan and in the U.S.. A new understanding of nuclear interaction has been stimulated, resulting in extensions of the conventional theoretical understanding of the fusion process. As theories are further developed, many advantages will become obvious including an easy and clean production of nuclear energy as well as elimination of present nuclear waste. These potential advantages must take precedence over the difficulty in accepting these novel concepts. The low energy nuclear processes take place in a solid lattice where the atomic and electron structures are able to interfere with the barrier between nuclei. This unusual structure has been hard to reproduce so that the phenomenon is still hard to replicate. However, persistent efforts in many laboratories have now identified several methods for creating this environment. This work will be reviewed, including original work by the author. See also: http://home.netcom.com/ storms2/index.html

Nuclear Receptor Activity and Liver Cancer Lesion Progression

EPA Science Inventory

Nuclear receptors (NRs) are ligand-activated transcription factors that control diverse cellular processes. Chronic stimulation of some NRs is a non-genotoxic mechanism of rodent liver cancer with unclear relevance to humans. We explored this question using human CAR, PXR, PPARα,...

Mode of action from dose-response microarray data: case study using 10 environmental chemicals

EPA Science Inventory

Ligand-activated nuclear receptors regulate many biological processes through complex interactions with biological macromolecules. Certain xenobiotics alter nuclear receptor signaling through direct or indirect interactions. Defining the mode of action of such xenobiotics is di...

Novel nuclear-cytoplasmic interaction in wheat (Triticum aestivum) induces vigorous plants

USDA-ARS?s Scientific Manuscript database

Interspecific hybridization can be considered an accelerator of evolution, otherwise a slow process, solely dependent on mutation and recombination. Upon interspecific hybridization, several novel interactions between nuclear and cytoplasmic genomes emerge which provide additional sources of diversi...

DUCTILE URANIUM FUEL FOR NUCLEAR REACTORS AND METHOD OF MAKING

DOEpatents

Zegler, S.T.

1963-11-01

The fabrication process for a ductile nuclear fuel alloy consisting of uranium, fissium, and from 0.25 to 1.0 wt% of silicon or aluminum or from 0.25 to 2 wt% of titanium or yttrium is presented. (AEC)

Front-end Design and Characterization for the ν-Angra Nuclear Reactor Monitoring Detector

NASA Astrophysics Data System (ADS)

Dornelas, T. I.; Araújo, F. T. H.; Cerqueira, A. S.; Costa, J. A.; Nóbrega, R. A.

2016-07-01

The Neutrinos Angra (ν-Angra) Experiment aims to construct an antineutrinos detection device capable of monitoring the Angra dos Reis nuclear reactor activity. Nuclear reactors are intense sources of antineutrinos, and the thermal power released in the fission process is directly related to the flow rate of these particles. The antineutrinos energy spectrum also provides valuable information on the nuclear source isotopic composition. The proposed detector will be equipped with photomultipliers tubes (PMT) which will be readout by a custom Amplifier-Shaper-Discriminator circuit designed to condition its output signals to the acquisition modules to be digitized and processed by an FPGA. The readout circuit should be sensitive to single photoelectron signals, process fast signals, with a full-width-half-amplitude of about 5 ns, have a narrow enough output pulse width to detect both particles coming out from the inverse beta decay (bar nue+p → n + e+), and its output amplitude should be linear to the number of photoelectrons generated inside the PMT, used for energy estimation. In this work, some of the main PMT characteristics are measured and a new readout circuit is proposed, described and characterized.

Diffusion studies with synchrotron Mössbauer spectroscopy

NASA Astrophysics Data System (ADS)

Jackson, J. M.

2011-12-01

Knowledge of diffusion properties is critical for understanding many physical and chemical processes in planetary interiors. For example, diffusion behavior provides constraints on chemical exchange and viscosity. Nuclear resonances open the window for observing diffusion properties under the extreme conditions that exist deep inside the Earth. Synchrotron Mössbauer spectroscopy (viz. nuclear forward scattering) makes use of synchrotron radiation coherently scattered in the forward direction after nuclear resonant excitation. The decay of the forward-scattered radiation is faster when atoms move on the time scale of the excited-state lifetime because of a loss of coherence. Such diffusion-activated processes lead to accelerated decay and line broadening in the measured signal. In the case of the Mössbauer active isotope 57Fe, the nuclear resonance at 14.4 keV has a natural lifetime of 141 ns. Therefore, one can observe diffusion events ranging from approximately one-sixth to 100 times the natural lifetime of 57Fe, which corresponds to diffusion coefficients of 10-16 and 10-13 m2/s, respectively and a two to three order of magnitude range of suitability. In this contribution, we will describe such measurements that access the microscopic details of the diffusion process for iron-bearing phases.

Outflows from Compact Objects in Supernovae and Novae

NASA Astrophysics Data System (ADS)

Vlasov, Andrey Dmitrievich

Originally thought of as a constant and unchanging place, the Universe is full of dramas of stars emerging, dying, eating each other, colliding, etc. One of the first transient phenomena noticed were called novae (the name means "new" in Latin). Years later, supernovae were discovered. Despite their names, both novae and supernovae are events in relatively old stars, with supernovae marking the point of stellar death. Known for thousands of years, supernovae and novae remain among the most studied events in our Universe. Supernovae strongly influence the circumstellar medium, enriching it with heavy elements and shocking it, facilitating star formation. Cosmic rays are believed to be accelerated in shocks from supernovae, with small contribution possibly coming from novae. Even though the basic physics of novae is understood, many questions remain unanswered. These include the geometry of the ejecta, why some novae are luminous radio or gamma-ray sources and others are not, what is the ultimate fate of recurrent novae, etc. Supernova explosions are the primary sources of elements heavier than hydrogen and helium. The elements up to nuclear masses A around 100 can form through successive nuclear fusion in the cores of stars starting with hydrogen. Beyond iron, the fusion becomes endothermic instead of exothermic. In addition, for these nuclear masses the temperatures required to overcome the Coulomb barriers are so high that the nuclei are dissociated into alpha particles and free nucleons. Hence all elements heavier than A around 100 should have formed by some other means. These heavier nuclear species are formed by neutron capture on seed nuclei close to or heavier than iron-group nuclei. Depending on the ratio between neutron-capture timescale and beta-decay timescale, neutron-capture processes are called rapid or slow (r- and s-processes, respectively). The s-process, which occurs near the valley of stable isotopes, terminates at Bi (Z=83), because after Bi there is a gap of four elements with no stable isotopes (Po, At, Rn, Ac) until we come to stable Th. The significant abundance of Th and U in our Universe therefore implies the presence of a robust source of r-process. The astrophysical site of r-process is still under debate. Here we present a study of a candidate site for r-process, neutrino-heated winds from newly-formed strongly magnetized, rapidly rotating neutron stars ("proto-magnetars"). Even though we find such winds are incapable of synthesizing the heaviest r-process elements like U and Th, they produce substantial amounts of weak r-process (38 Supernova explosions are the primary sources of elements heavier than hydrogen and helium. The elements up to nuclear masses A around 100 can form through successive nuclear fusion in the cores of stars starting with hydrogen. Beyond iron, the fusion becomes endothermic instead of exothermic. In addition, for these nuclear masses the temperatures required to overcome the Coulomb barriers are so high that the nuclei are dissociated into alpha particles and free nucleons. Hence all elements heavier than A around 100 should have formed by some other means. These heavier nuclear species are formed by neutron capture on seed nuclei close to or heavier than iron-group nuclei. Depending on the ratio between neutron-capture timescale and beta-decay timescale, neutron-capture processes are called rapid or slow (r- and s-processes, respectively). The s-process, which occurs near the valley of stable isotopes, terminates at Bi (Z=83), because after Bi there is a gap of four elements with no stable isotopes (Po, At, Rn, Ac) until we come to stable Th. The significant abundance of Th and U in our Universe therefore implies the presence of a robust source of r-process. The astrophysical site of r-process is still under debate. Here we present a study of a candidate site for r-process, neutrino-heated winds from newly-formed strongly magnetized, rapidly rotating neutron stars ("proto-magnetars"). Even though we find such winds are incapable of synthesizing the heaviest r-process elements like U and Th, they produce substantial amounts of weak r-process (38.

The impact of (n, γ) reaction rate uncertainties of unstable isotopes near N = 50 on the i-process nucleosynthesis in He-shell flash white dwarfs

NASA Astrophysics Data System (ADS)

Denissenkov, Pavel; Perdikakis, Georgios; Herwig, Falk; Schatz, Hendrik; Ritter, Christian; Pignatari, Marco; Jones, Samuel; Nikas, Stylianos; Spyrou, Artemis

2018-05-01

The first-peak s-process elements Rb, Sr, Y and Zr in the post-AGB star Sakurai's object (V4334 Sagittarii) have been proposed to be the result of i-process nucleosynthesis in a post-AGB very-late thermal pulse event. We estimate the nuclear physics uncertainties in the i-process model predictions to determine whether the remaining discrepancies with observations are significant and point to potential issues with the underlying astrophysical model. We find that the dominant source in the nuclear physics uncertainties are predictions of neutron capture rates on unstable neutron rich nuclei, which can have uncertainties of more than a factor 20 in the band of the i-process. We use a Monte Carlo variation of 52 neutron capture rates and a 1D multi-zone post-processing model for the i-process in Sakurai's object to determine the cumulative effect of these uncertainties on the final elemental abundance predictions. We find that the nuclear physics uncertainties are large and comparable to observational errors. Within these uncertainties the model predictions are consistent with observations. A correlation analysis of the results of our MC simulations reveals that the strongest impact on the predicted abundances of Rb, Sr, Y and Zr is made by the uncertainties in the (n, γ) reaction rates of 85Br, 86Br, 87Kr, 88Kr, 89Kr, 89Rb, 89Sr, and 92Sr. This conclusion is supported by a series of multi-zone simulations in which we increased and decreased to their maximum and minimum limits one or two reaction rates per run. We also show that simple and fast one-zone simulations should not be used instead of more realistic multi-zone stellar simulations for nuclear sensitivity and uncertainty studies of convective–reactive processes. Our findings apply more generally to any i-process site with similar neutron exposure, such as rapidly accreting white dwarfs with near-solar metallicities.

ADVANCED CERAMIC MATERIALS FOR NEXT-GENERATION NUCLEAR APPLICATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Marra, J.

2010-09-29

Rising global energy demands coupled with increased environmental concerns point to one solution; they must reduce their dependence on fossil fuels that emit greenhouse gases. As the global community faces the challenge of maintaining sovereign nation security, reducing greenhouse gases, and addressing climate change nuclear power will play a significant and likely growing role. In the US, nuclear energy already provides approximately one-fifth of the electricity used to power factories, offices, homes, and schools with 104 operating nuclear power plants, located at 65 sites in 31 states. Additionally, 19 utilities have applied to the US Nuclear Regulatory Commission (NRC) formore » construction and operating licenses for 26 new reactors at 17 sites. This planned growth of nuclear power is occurring worldwide and has been termed the 'nuclear renaissance.' As major industrial nations craft their energy future, there are several important factors that must be considered about nuclear energy: (1) it has been proven over the last 40 years to be safe, reliable and affordable (good for Economic Security); (2) its technology and fuel can be domestically produced or obtained from allied nations (good for Energy Security); and (3) it is nearly free of greenhouse gas emissions (good for Environmental Security). Already an important part of worldwide energy security via electricity generation, nuclear energy can also potentially play an important role in industrial processes and supporting the nation's transportation sector. Coal-to-liquid processes, the generation of hydrogen and supporting the growing potential for a greatly increased electric transportation system (i.e. cars and trains) mean that nuclear energy could see dramatic growth in the near future as we seek to meet our growing demand for energy in cleaner, more secure ways. In order to address some of the prominent issues associated with nuclear power generation (i.e., high capital costs, waste management, and proliferation), the worldwide community is working to develop and deploy new nuclear energy systems and advanced fuel cycles. These new nuclear systems address the key challenges and include: (1) extracting the full energy value of the nuclear fuel; (2) creating waste solutions with improved long term safety; (3) minimizing the potential for the misuse of the technology and materials for weapons; (4) continually improving the safety of nuclear energy systems; and (5) keeping the cost of energy affordable.« less

Precipitate hydrolysis process for the removal of organic compounds from nuclear waste slurries

DOEpatents

Doherty, Joseph P.; Marek, James C.

1989-01-01

A process for removing organic compounds from a nuclear waste slurry comprising reacting a mixture of radioactive waste precipitate slurry and an acid in the presence of a catalytically effective amount of a copper (II) catalyst whereby the organic compounds in the precipitate slurry are hydrolyzed to form volatile organic compounds which are separated from the reacting mixture. The resulting waste slurry, containing less than 10 percent of the orginal organic compounds, is subsequently blended with high level radioactive sludge and transferred to a virtrification facility for processing into borosilicate glass for long-term storage.

Engineering Design Elements of a Two-Phase Thermosyphon to Trannsfer NGNP Nuclear Thermal Energy to a Hydrogen Plant

DOE Office of Scientific and Technical Information (OSTI.GOV)

Piyush Sabharwal

2009-07-01

Two hydrogen production processes, both powered by a Next Generation Nuclear Plant (NGNP), are currently under investigation at Idaho National Laboratory. The first is high-temperature steam electrolysis, which uses both heat and electricity; the second is thermo-chemical production through the sulfur iodine process primarily using heat. Both processes require a high temperature (>850°C) for enhanced efficiency; temperatures indicative of the NGNP. Safety and licensing mandates prudently dictate that the NGNP and the hydrogen production facility be physically isolated, perhaps requiring separation of over 100 m.

Mechanisms of nuclear lamina growth in interphase.

PubMed

Zhironkina, Oxana A; Kurchashova, Svetlana Yu; Pozharskaia, Vasilisa A; Cherepanynets, Varvara D; Strelkova, Olga S; Hozak, Pavel; Kireev, Igor I

2016-04-01

The nuclear lamina represents a multifunctional platform involved in such diverse yet interconnected processes as spatial organization of the genome, maintenance of mechanical stability of the nucleus, regulation of transcription and replication. Most of lamina activities are exerted through tethering of lamina-associated chromatin domains (LADs) to the nuclear periphery. Yet, the lamina is a dynamic structure demonstrating considerable expansion during the cell cycle to accommodate increased number of LADs formed during DNA replication. We analyzed dynamics of nuclear growth during interphase and changes in lamina structure as a function of cell cycle progression. The nuclear lamina demonstrates steady growth from G1 till G2, while quantitative analysis of lamina meshwork by super-resolution microscopy revealed that microdomain organization of the lamina is maintained, with lamin A and lamin B microdomain periodicity and interdomain gap sizes unchanged. FRAP analysis, in contrast, demonstrated differences in lamin A and B1 exchange rates; the latter showing higher recovery rate in S-phase cells. In order to further analyze the mechanism of lamina growth in interphase, we generated a lamina-free nuclear envelope in living interphase cells by reversible hypotonic shock. The nuclear envelope in nuclear buds formed after such a treatment initially lacked lamins, and analysis of lamina formation revealed striking difference in lamin A and B1 assembly: lamin A reassembled within 30 min post-treatment, whereas lamin B1 did not incorporate into the newly formed lamina at all. We suggest that in somatic cells lamin B1 meshwork growth is coordinated with replication of LADs, and lamin A meshwork assembly seems to be chromatin-independent process.

The Defense Threat Reduction Agency's Technical Nuclear Forensics Research and Development Program

NASA Astrophysics Data System (ADS)

Franks, J.

2015-12-01

The Defense Threat Reduction Agency (DTRA) Technical Nuclear Forensics (TNF) Research and Development (R&D) Program's overarching goal is to design, develop, demonstrate, and transition advanced technologies and methodologies that improve the interagency operational capability to provide forensics conclusions after the detonation of a nuclear device. This goal is attained through the execution of three focus areas covering the span of the TNF process to enable strategic decision-making (attribution): Nuclear Forensic Materials Exploitation - Development of targeted technologies, methodologies and tools enabling the timely collection, analysis and interpretation of detonation materials.Prompt Nuclear Effects Exploitation - Improve ground-based capabilities to collect prompt nuclear device outputs and effects data for rapid, complementary and corroborative information.Nuclear Forensics Device Characterization - Development of a validated and verified capability to reverse model a nuclear device with high confidence from observables (e.g., prompt diagnostics, sample analysis, etc.) seen after an attack. This presentation will outline DTRA's TNF R&D strategy and current investments, with efforts focusing on: (1) introducing new technical data collection capabilities (e.g., ground-based prompt diagnostics sensor systems; innovative debris collection and analysis); (2) developing new TNF process paradigms and concepts of operations to decrease timelines and uncertainties, and increase results confidence; (3) enhanced validation and verification (V&V) of capabilities through technology evaluations and demonstrations; and (4) updated weapon output predictions to account for the modern threat environment. A key challenge to expanding these efforts to a global capability is the need for increased post-detonation TNF international cooperation, collaboration and peer reviews.

The Use of Basalt, Basalt Fibers and Modified Graphite for Nuclear Waste Repository - 12150

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gulik, V.I.; Biland, A.B.

2012-07-01

New materials enhancing the isolation of radioactive waste and spent nuclear fuel are continuously being developed.. Our research suggests that basalt-based materials, including basalt roving chopped basalt fiber strands, basalt composite rebar and materials based on modified graphite, could be used for enhancing radioactive waste isolation during the storage and disposal phases and maintaining it during a significant portion of the post-closure phase. The basalt vitrification process of nuclear waste is a viable alternative to glass vitrification. Basalt roving, chopped basalt fiber strands and basalt composite rebars can significantly increase the strength and safety characteristics of nuclear waste and spentmore » nuclear fuel storages. Materials based on MG are optimal waterproofing materials for nuclear waste containers. (authors)« less

The evolutionary processes of mitochondrial and chloroplast genomes differ from those of nuclear genomes

NASA Astrophysics Data System (ADS)

Korpelainen, Helena

2004-11-01

This paper first introduces our present knowledge of the origin of mitochondria and chloroplasts, and the organization and inheritance patterns of their genomes, and then carries on to review the evolutionary processes influencing mitochondrial and chloroplast genomes. The differences in evolutionary phenomena between the nuclear and cytoplasmic genomes are highlighted. It is emphasized that varying inheritance patterns and copy numbers among different types of genomes, and the potential advantage achieved through the transfer of many cytoplasmic genes to the nucleus, have important implications for the evolution of nuclear, mitochondrial and chloroplast genomes. Cytoplasmic genes transferred to the nucleus have joined the more strictly controlled genetic system of the nuclear genome, including also sexual recombination, while genes retained within the cytoplasmic organelles can be involved in selection and drift processes both within and among individuals. Within-individual processes can be either intra- or intercellular. In the case of heteroplasmy, which is attributed to mutations or biparental inheritance, within-individual selection on cytoplasmic DNA may provide a mechanism by which the organism can adapt rapidly. The inheritance of cytoplasmic genomes is not universally maternal. The presence of a range of inheritance patterns indicates that different strategies have been adopted by different organisms. On the other hand, the variability occasionally observed in the inheritance mechanisms of cytoplasmic genomes reduces heritability and increases environmental components in phenotypic features and, consequently, decreases the potential for adaptive evolution.

Indicator system for advanced nuclear plant control complex

DOEpatents

Scarola, Kenneth; Jamison, David S.; Manazir, Richard M.; Rescorl, Robert L.; Harmon, Daryl L.

1993-01-01

An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system (72) which is nuclear qualified for rapid response to changes in plant parameters and a component control system (64) which together provide a discrete monitoring and control capability at a panel (14-22, 26, 28) in the control room (10). A separate data processing system (70), which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs (84) and a large, overhead integrated process status overview board (24). The discrete indicator and alarm system (72) and the data processing system (70) receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accident conditions, thereby avoiding the need for him to assimilate data from each sensor individually. The integrated process status board (24) is at the apex of an information hierarchy that extends through four levels and provides access at each panel to the full display hierarchy. The control room panels are preferably of a modular construction, permitting the definition of inputs and outputs, the man machine interface, and the plant specific algorithms, to proceed in parallel with the fabrication of the panels, the installation of the equipment and the generic testing thereof.

Console for a nuclear control complex

DOEpatents

Scarola, Kenneth; Jamison, David S.; Manazir, Richard M.; Rescorl, Robert L.; Harmon, Daryl L.

1993-01-01

An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system (72) which is nuclear qualified for rapid response to changes in plant parameters and a component control system (64) which together provide a discrete monitoring and control capability at a panel (14-22, 26, 28) in the control room (10). A separate data processing system (70), which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs (84) and a large, overhead integrated process status overview board (24). The discrete indicator and alarm system (72) and the data processing system (70) receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accident conditions, thereby avoiding the need for him to assimilate data from each sensor individually. The integrated process status board (24) is at the apex of an information hierarchy that extends through four levels and provides access at each panel to the full display hierarchy. The control room panels are preferably of a modular construction, permitting the definition of inputs and outputs, the man machine interface, and the plant specific algorithms, to proceed in parallel with the fabrication of the panels, the installation of the equipment and the generic testing thereof.

Alarm system for a nuclear control complex

DOEpatents

Scarola, Kenneth; Jamison, David S.; Manazir, Richard M.; Rescorl, Robert L.; Harmon, Daryl L.

1994-01-01

An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system (72) which is nuclear qualified for rapid response to changes in plant parameters and a component control system (64) which together provide a discrete monitoring and control capability at a panel (14-22, 26, 28) in the control room (10). A separate data processing system (70), which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs (84) and a large, overhead integrated process status overview board (24). The discrete indicator and alarm system (72) and the data processing system (70) receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accident conditions, thereby avoiding the need for him to assimilate data from each sensor individually. The integrated process status board (24) is at the apex of an information hierarchy that extends through four levels and provides access at each panel to the full display hierarchy. The control room panels are preferably of a modular construction, permitting the definition of inputs and outputs, the man machine interface, and the plant specific algorithms, to proceed in parallel with the fabrication of the panels, the installation of the equipment and the generic testing thereof.

Method of installing a control room console in a nuclear power plant

DOEpatents

Scarola, Kenneth; Jamison, David S.; Manazir, Richard M.; Rescorl, Robert L.; Harmon, Daryl L.

1994-01-01

An advanced control room complex for a nuclear power plant, including a discrete indicator and alarm system (72) which is nuclear qualified for rapid response to changes in plant parameters and a component control system (64) which together provide a discrete monitoring and control capability at a panel (14-22, 26, 28) in the control room (10). A separate data processing system (70), which need not be nuclear qualified, provides integrated and overview information to the control room and to each panel, through CRTs (84) and a large, overhead integrated process status overview board (24). The discrete indicator and alarm system (72) and the data processing system (70) receive inputs from common plant sensors and validate the sensor outputs to arrive at a representative value of the parameter for use by the operator during both normal and accident conditions, thereby avoiding the need for him to assimilate data from each sensor individually. The integrated process status board (24) is at the apex of an information hierarchy that extends through four levels and provides access at each panel to the full display hierarchy. The control room panels are preferably of a modular construction, permitting the definition of inputs and outputs, the man machine interface, and the plant specific algorithms, to proceed in parallel with the fabrication of the panels, the installation of the equipment and the generic testing thereof.