The effect of a sawtooth crash on the radial distribution of the slowing down fusion product tritons and on beams ions, is examined with measurements of the 2.5 MeV and 14 MeV neutron emission line-integrals before and after sawtooth crashes. In deuterium discharges, the 14 MeV neutron production was wholly attributable to burnup of the 1 MeV fusion product tritons from d-dfusion. The local emissivity of 14 MeV neutrons, and hence of the profile of thermalizing tritons, is shown to be only weakly affected by crashes in the discharges studied. This is in contradiction with the apparent behaviour of injected beam ions as deduced from a study of the considerable changes in local emissivity of the 2.5 MeV neutrons. Nevertheless, the behaviour of the fusion product tritons is consistent with the scaling of the beam injected deuterium. 1 ref., 6 figs.
The importance of neutron measurements both as a succinct measure of the progress to fusion ignition using the magnetic confinement route and also as a diagnostic of plasma conditions is discussed. The various neutron diagnostic systems that have been or are being constructed by AERE Harwell for JET are described. The properties to be measured by such diagnostics are clearly identified and some results obtained with the installed diagnostics during d-d plasmas are presented.
The objective of this work was to combine asymmetric somatic hybridization (donor-recipient fusion or gamma fusion) to microprotoplast-mediated chromosome transfer, as a tool to be used for chromosome mapping in Citrus. Swinglea glutinosa micro protoplasts were irradiated either with 50, 70, 100 or 200 gamma rays and fused to cv. Ruby Red grapefruit or Murcott tangor protoplasts. Cell colonies were successfully formed and AFLP analyses confirmed presence of S. glutinosa in both 'Murcott' tangor and 'Ruby Red' grapefruit genomes. (author)
Recent improvements in cell purification and transplantation techniques have contributed to the identification of cell populations known as tumor-initiating cells (TIC). This discovery has led to the -cancer stem cell hierarchy- concept, which holds that tumors are organized as a hierarchy of malignant tissues sustained by such TIC. However, this concept remains controversial. In this review, we examine recent advances in cancer stem cell research that have been generated from studies of Philadelphia (Ph) chromosome-positive leukemia. The abnormal Ph chromosome, which arises from a translocation creating the BCR-ABL1 fusion gene, is most commonly associated with chronic myelogenous leukemia (CML) and precursor B cell acute lymphoblastic leukemia (B-ALL). Examination of the pathophysiology ...
The National Ignition Facility (NIF) will be a U.S. Department of Energy (DOE) national center for inertial confinement fusion (ICF) and other research into the physics of high temperatures and high densities, and a vital element of the DOE`s nuclear weapons Stockpile Stewardship and Management Program. It will be used by scientists from a numerous different institutions and disciplines to support research advancements in national security, energy, basic science, and economic development. Multiple powerful laser beams will `ignite` small fusion targets, helping liberate more energy than is required to initiate the fusion reactions. This paper discusses the Design for Environment process for NIF, some of the subsequent activities resulting from the initial study, and a few of the lessons learned from this process. Subsequent activities include the development of a Pollution Prevention and Waste Minimization Plan (P2/WMin) ...
Individuals with male factor infertility resulting from idiopathic oligo-, astheno- or teratozoospermia are frequently offered IVF in an attempt to increase their chances of having a child. A concern remains whether these infertile males have an elevated risk of transmitting chromosomal abnormalities to their offspring. Sperm chromosomal complements from these men were assayed using the human sperm/hamster oocyte fusion system and fluorescence in situ hybridization (FISH) on sperm nuclei. For each of 5 infertile patients, 100 sperm karyotypes were analyzed and multicolour FISH analysis was performed on a minimum of 10,000 sperm nuclei for each chromosome-specific DNA probe for chromosomes 1 (pUC1.77), 12 (D12Z3), X (XC) and Y (DYZ3). As a group, the infertile patients showed increased frequencies of both numerical ({chi}{sup 2}=17.26, {proportional_to} <0.001) and total ...
The Plasma and Ion Source Technology Group at the Lawrence Berkeley National Laboratory have been developing rf-driven ion sources for the last two decades. These sources are being used to generate both positive and negative ion beams. Some of these sources are operating in particle accelerators such as the Spallation Neutron Source (SNS) at Oak Ridge, while others are being employed in various industrial ion beam systems. There are four areas where the rf-driven ion sources are commonly used in industry. (1) In semiconductor manufacturing, rf-driven sources have found important applications in plasma etching, ion beam implantation, and ion beam lithography. (2) In material analysis and surface modification, miniature rf-ion sources can be found in focused ion beam systems. They can provide ion beams of essentially any element in the Periodic Table. The newly developed combined rf ion-electron beam unit improves greatly the performance of the secondary ion mass spectrometry tool. (3) ...
TiH{sub 2} and TiD{sub 2} thick targets were bombarded with 100 to 200 keV protons or deuterons. Evidence for nuclear reactions was obtained by means of a surface barrier particle detector. Deuteron irradiation of TiD{sub 2} produced these observations: copious {approx}2.5 MeV neutrons and {approx}3 MeV protons from direct D-D reactions; gamma rays from p,{gamma} and n,{gamma} reactions; {approx}14 MeV protons from the secondary d({sup 3}He, p){alpha} reaction; and a signal between {approx}6-12 MeV that Kasagi et al. has tentatively identified as protons from the fusion of three deuterium nuclei. However, this signal has in it a strong interference signal from either neutrons or gamma rays that directly deposit energy in the detector. This interference spectra was measured by placing a thick absorber in front of the detector that stops up to 20 MeV protons, but not gamma rays or neutrons. More experiments must be done before we can confirm or ...
This paper describes activation measurements of the neutrons from fusion plasmas. We are primarily interested in two narrow bands of neutron energies around 2.5 and 14 MeV. The d-d reaction has two branches with nearly equal probability, one generating a 0.8 MeV {sup 3}He nucleus and a 2.45 MeV neutron, the other a 1 MeV triton and a 3 MeV proton. The d-t fusion generates a 3.5 MeV alpha particle and a 14 MeV neutron. The triton burnup can be defined as the ratio of triton removal rate to triton generation rate. The burnup depends on how well the tritons are confined in the plasma during their slowing down to energies that make d-t fusion probable. It is important to study the tritons as they have similar kinematics to the 3.5 MeV alpha particles in a d-t plasma. Threshold reactions make a distinction between 2.5 and 14 MeV neutrons possible. For calculating the triton burnup, the total emission from ...
Argonne National Laboratory (ANL) is implementing waste minimization and pollution prevention activities into its conduct of decontamination and decommissioning (D&D) projects. Many of these activities are rather straight forward and simple approaches, yet they are often overlooked and not implemented as often as they should or could be. Specific activities involving recycling and reuse of materials and structures, which have proven useful in lowering decommissioning and disposal costs on D&D projects at ANL are presented.
The COOH-terminus of telomerase reverse transcriptase (hTERT) has been shown to participatein the nuclear translocation of TERT. Here, we constructed plasmids expressing the COOH-terminal M(r) 27,000 polypeptide of hTERT (hTERTC27) withthe telomerase RNA-binding domains and the reverse transcriptase domains deleted. We showed that ectopic overexpression of this polypeptide caused a defect in telomere maintenance in hTERT-positive HeLa cells, which led to senescence-like growth arrest and apoptosis. The hTERTC27 appears to work by inducing telomere dysfunction, exemplified by significantly increased anaphase chromosome end-to-end fusion events in transfected cells. Significantly, it had no effect on the cellular telomerase enzymatic activity or telomere length. The in vivo effect was further demonstrated as HeLa cells stably expressing hTERTC27 have significantly lower growth rate and reduced tumorigenicity in nude mice xenografts. Results from ...
MAGNETIC FORMING BERYLLIUM COIL ASSEMBLY. By. J. W. Rogers, D. D. Wier, and M. E. Davis. Department of Electrical Engineering. Mississippi State University ...
Examination and assessment of 140 liveborn and stillborn infants referred within two weeks of birth for chromosome analysis showed that 48 had Down's syndrome, 12 other chromosome abnormalities, 17...Full Text Available
...] gueconwpa~05-05-05 How is Macro News Transmitted to Exchange Rates? (December 2003) by Martin D. D. Evans(Georgetown University and NBER) and Richard K. Lyons(U.C. Berkeley and NBER, Haas School of Business) [Downloadable!] gueconwpa~05-05-04 A New Micro Model of Exchange Rate Dynamics (March 2004) by Martin D. D. Evans(Georgetown University and ...
Variation for wheat (Triticum aestivum L.) grain yield and its component traits was documented in a `Cheyenne¿ x Cheyenne (`Wichita¿ 3A) recombinant inbred chromosome line population. In the present study, a population of 223 Cheyenne (Wichita 3A) recombinant inbred chromosome lines was used to map ...
Today you will learn about the parts of DNA and what DNA, genes and chromosomes are. Today you will learn what DNA, genes and chromosomes are and the parts of the DNA molecule. Look at all of the websites, take whatever notes you need to. At the end of the assignment, be able to describle DNA, the parts of DNA, genes and chromosomes. Covers Biology Core Curriculum, ...
Analysis of the pattern of the chromosomal localization of quantitative trait loci (QTLs) is necessary for comprehensively understanding their functions. The chromosomal localization of QTLs controlling milk production traits has been studied in cattle chromosomes. The distribution of QTLs between chromosomes has proved to be binomial. Their distribution along each chromosome was, in general, uniform, except for the QTLs controlling the somatic cell score (SCS), which tended towards telomeric location. However, there are chromosomes either enriched with or particularly poor in QTLs. The QTL distribution patters are the most similar for the milk yield (M) and milk protein yield (P) and for milk fat yield (F) and milk fat content (%F). The pattern of the SCS QTLs stands out among those of ot...
A tutorial account is given of the main characteristics and distinctive features of conceptual magnetic fusion systems employing the magnetic mirror principle. These features are related to the potential advantages that mirror-based fusion systems may exhibit for the generation of economic fusion power.
The human zinc finger protein genes (ZFX/Y) were identified as a result of a systematic search for the testis-determining factor gene on the human Y chromosome. Although they play no direct role in sex determination, they are of particular interest because they are highly conserved among mammals, birds, and amphibians and because, in eutherian mammals at least, they have active alleles on both the X and the Y chromosomes outside the pseudoautosomal region. We used in situ hybridization to localize the homologues of the zinc finger protein gene to chromosome 1 of the Australian echidna and to an equivalent position on chromosomes 1 and 2 of the playtpus. The localization to platypus chromosome 1 was confirmed by Southern analysis of a Chinese hamster [times] platypus cell hybrid retaining most of platypus chromosome 1. This localization is consistent with the ...
Flow cytogenetics is a rapidly developing technology which complements rather than supplants the traditional methods of cytogenetic analysis. As an adjunctive approach to chromosome classification, flow systems measurements of isolated chromosomes give new information relative to the enrichment of A-T or G-C base sequences on specific chromosomes. As a result, chromosomal fluorescence polymorphisms both within and among individuals that are not always associated with banding polymorphisms can be detected. Finally, flow sorting provides bulk quantities of highly purified chromosomes for use in biochemical studies. Methodology is detailed. (PSB)
The fusion breeder is a fusion reactor designed with special blankets to maximize the transmutation by 14 MeV neutrons of uranium-238 to plutonium or thorium to uranium-233 for use as a fuel for fission reactors. Breeding fissile fuels has not been a goal of the US fusion energy program. This paper suggests it is time for a policy change to make the fusion breeder a goal of the US fusion program and the US nuclear energy program. The purpose of this paper is to suggest this policy change be made and tell why it should be made, and to outline specific research and development goals so that the fusion breeder will be developed in time to meet fissile fuel needs.
The insertion of innovative technologies to replace baseline technologies used in cost estimation and planning of DOE D&D projects is considered a high risk endeavor by project and programmatic decision makers. It is almost always considered safer to go with the {open_quotes}devil you know{close_quotes} than use a new or untried technology, methodology or system. The decision on the specific technology to be utilized to remediate a problem is often made months or years in advance of execution, and the highly proscriptive documentation of agreements necessary to obtain stakeholder and regulator approval of remedial plans is often counterproductive to considering improved technologies.
Pathogenicity islands (PAIs) are chromosomal clusters of pathogen-specific virulence genes often found at tRNA loci. In the Yersinia pseudotuberculosis 32777 chromosome, we characterized...Full Text Available
FRAXA is one of a number of fragile sites in human chromosomes that are induced by agents like fluorodeoxyuridine (FdU) that affect intracellular thymidylate levels. FRAXA coincides with a >200...Full Text Available
Bipolar spindles assemble in the absence of centrosomes in the oocytes of many species. In Drosophila melanogaster oocytes, the chromosomes have been proposed to initiate spindle assembly...Full Text Available
Using a genetic screen we have identified two chromosomal genes, cusRS (ylcA ybcZ), from Escherichia coli K-12 that encode a two-component, signal...Full Text Available
The content of guanine+cytosine varies markedly along the chromosomes of homeotherms and great effort has been devoted to studying this heterogeneity and its biological implications. Already...Full Text Available
Forum domains are stretches of chromosomal DNA that are excised from eukaryotic chromosomes during their spontaneous non-random fragmentation. Most forum domains are 50–200 kb in length....Full Text Available
The recent assembly of the silkworm Bombyx mori genome with 432 Mb on 28 holocentric chromosomes has become a reference in the genomic analysis of the very diverse Order of Lepidoptera....Full Text Available
Contents The aim of this study was a cytogenetic analysis of stallions semen to find sex chromosome aberrations and to determine if there was an association between stallion-s age and aberration frequency for the sex chromosomes. Sperm samples were collected from 22 stallions of various age from 3 to 23-years. Multicolour FISH was performed on each sample, using probes for the sex chromosomes and EGFR gene, localized on 4p12 in domestic horse. A total of 26199 sperm cells were analysed (from 1 070 to 1 532 per animal). Among the analysed cells, there were 50.318% with X chromosome, 48.543% with Y chromosome and 1.139% with aberrant chromosomes. The frequency of aberrations was: sex chromosomes nullisomy (0.466%), XY aneuploidy (0.454%), XX disomy (0.146%), YY disomy (0.041%), diploidy (0.0...
Changes in the number of chromosomes, but also variations in the copy number of chromosomal regions have been described in various pathological conditions, such as cancer and aneuploidy, but also in...Full Text Available
This study examined the genetic basis of hypertension and renal disease in Dahl SS/Mcwi (Dahl Salt-Sensitive) rats using a complete chromosome substitution panel of consomic rats in which each of the...Full Text Available
In situ hybridization, a powerful tool for the molecular cytogeneticist, can be used to physically map repetitive, low-copy, and unique DNA sequences in plant chromosomes. With the availability of a...Full Text Available
The discovery that hepatitis B virus (HBV) integrates into host chromosomes raises the question of whether such viral DNA integration correlates directly with the activation of specific oncogenes or...Full Text Available
A chromosomally located β-lactamase gene, cloned and expressed in Escherichia coli from a reference strain of the enterobacterial species Kluyvera cryocrescens,...Full Text Available
Gene expression from bacterial artificial chromosome (BAC) clones has been demonstrated to facilitate physiologically relevant levels compared to viral and nonviral cDNA vectors. BACs are large enough...Full Text Available
Chapter 5, describes some of the most important molecular methods used in the study of chromosome structure and function. The methods discussed include fragmentation of DNA, cloning, flow cytometry and chromosome sorting, is situ hybridization, polymerase chain reaction (PCR), and yeast artificial chromosomes (YACs). 18 refs., 3 figs., 1 tab.
Quantities and compositions of non-tritium radioactive waste are estimated for some current conceptual fusion reactor designs, and disposal of large amounts of radioactive waste appears necessary. Although the initial radioactivity of fusion reactor and f...
The potential public safety impacts from accidents in conceptual fusion power plants were investigated. Fusion was found to have some potential for accidents, as does any energy generating system. Functions of fusion power plants were identified that possess sufficient potential for an accidental release of toxic materials to the environment. An assessment was made of the impact of the potential accidents and recommendations are included for R and D that will allow incorporation of safety concerns in fusion power plant design. This work was based on a review of information available in conceptual design documents of fusion reactor systems.
The potential public safety impacts from accidents in conceptual fusion power plants were investigated. Fusion was found to have some potential for accidents, as does any energy generating system. Functions of fusion power plants were identified that possess sufficient potential for an accidental release of toxic materials to the environment. An assessment was made of the impact of the potential accidents and recommendations are included for R and D that will allow incorporation of safety concerns in fusion power plant design. This work was based on a review of information available in conceptual design documents of fusion reactor systems.
The most important and difficult part of materials research for fusion reactor is realized to be irradiation studies of fusion reactor materials. Irradiation studies of fusion reactor materials utilizing FFTF/MOTA, as one of Japan/U.S.A. Fusion Collaboration Programs, have important role to establish fundamental understanding of heavy irradiation effects on materials behavior and properties and to develop methods and technologies for advanced irradiation studies under fusion reactor environment. This paper briefly reviews the history, the state of the art, and the future of the FFTF/MOTA program. (author).
Conceptual fusion reactor studies over the past 10 to 15 years have projected systems that may be too large, complex, and costly to be of commercial interest. One main direction for improved fusion reactors points towards smaller, higher-power-density approaches. First-order economic issues (i.e., unit direct cost and cost of electricity) are used to support the need for more compact fusion reactors. A generic fusion physics/engineering/costing model is used to provide a quantiative basis for these arguments for specific fusion concepts.
Differentiating characteristics of magnetic confinement systems having externally generated magnetic fields that are open'' are listed and discussed in the light of their several potential advantages for fusion power systems. It is pointed out that at this stage of fusion research high-Q'' (as deduced from long energy confinement times) is not necessarily the most relevant criterion by which to judge the potential of alternate fusion approaches for the economic generation of fusion power. An example is given of a hypothetical open-geometry fusion power system where low-Q operation is essential to meeting one of its main objectives (low neutron power flux).
... the open source OpenMap Java toolkit from BBN ... 2001), Handbook of Multisensor Data Fusion ... Oxenham (2002), Sensor Registration Using Airlanes ...
We develop the notions of fusion for representations of the WA_2 algebra along the lines of Feigin and Fuchs. We present some explicit calculations for a WA_2 minimal model. (orig.).
We present a novel preparation method for studies of in vitro reconstituted mitotic chromosomes from Xenopus laevis egg extracts. This method involves a gentle adsorption of chromosomes from the extracts using surface affinity enrichment, followed by plunge freezing, freeze-substitution and cryo-embedding before examination by EM tomography. For comparison, chromosomes were also prepared by a conventional method, which included immobilization of chromosomes in agarose and a room-temperature dehydration (embedding) protocol. Three-dimensional reconstructions showed that samples prepared with the new method have a greater interconnectivity of sub-structural features and a higher compaction ratio together with an apparently less perturbed chromatin structure than those prepared using the conventional approach. The implications of the new method for the preparation of other difficult samples and additional ...
The gene encoding the human type I pituitary adenylate cyclase activating polypeptide receptor (ADCYAP1R1) was mapped to chromosome 7 by PCR analysis of genomic DNA from a human/rodent somatic cell hybrid mapping panel. This assignment was confirmed and the gene localized to chromosome band 7p14 by fluorescence in situ hybridization. A yeast artificial chromosome containing ADCYAP1R1 was identified in the CEPH {open_quotes}B{close_quotes} Mega-YAC library. This YAC includes two highly polymorphic dinucleotide repeat sequences that will facilitate genetic studies of the contribution of ADCYAP1R1 in disease states of the central nervous and neuroendocrine systems. 13 refs., 1 fig.
Excessive physical activity plays an important role in the progression of anorexia nervosa (AN) by accelerating weight loss during dietary restriction. To search for mechanisms underlying this trait, a panel of mouse chromosome substitution strains derived from C57BL/6J and A/J strains was exposed to a scheduled feeding paradigm and to voluntary running wheel (RW) access. Here, we showed that A/J chromosomes 4, 12 and 13 contribute to the development of a disrupted RW activity in response to daily restricted feeding. This pattern is characterized by intense RW activity during the habitual rest phase and leads to accelerated body weight loss. Regions on mouse chromosomes 4, 12 and 13 display homology with regions on human chromosomes linked with anxiety and obsessionality in AN cohorts. The...
We determined the chromosomal localization and structure of the gene encoding human type II inosine 5{prime}-monophosphate dehydrogenase (IMPDH, EC 1.1.1.205), an enzyme associated with cellular proliferation, malignant transformation, and differentiation. Using polymerase chain reaction (PCR) primers specific for type II IMPDH, we screened a panel of human-Chinese hamster cell somatic hybrids and a separate deletion panel of chromosome 3 hybrids and localized the gene to 3p21.1{yields}p24.2. Two overlapping yeast artificial chromosome clones containing the full gene for type II IMPDH were isolated and a physical map of 117 kb of human genomic DNA in this region of chromosome 3 was constructed. The gene for type II IMPDH was localized and oriented on this map and found to span no more than 12.5 kb.
We aim to isolate cDNAs mapping to human chromosome 16 and localise such cDNAs on the high resolution physical map. In collaboration with LANL, PCR primers will be synthesised from cDNA sequences mapped to chromosome 16 and used as ESTs in the generation of mega-YAC contigs for this chromosome. Probing of high density cosmid grids will enable integration of the ESTs into cosmid contigs and location of the cosmid contigs on the YAC contig. A hn-cDNA library has been constructed from the hybrid CY18 which contains chromosome 16 as the only human chromosome. A modified screening protocol has been successfully developed and 15 hn-cDNA clones have been sequenced and localised on the hybrid map. Sequence analysis of four of these revealed that they were known cDNAs, which are now mapped to chromosome 16. Development of techniques to allow the isolation of longer cDNAs ...
The recently described retinoid X receptors (RXRs) respond to the novel retinoid 9-cis-retinoic acid and also serve as heterodimeric partners for the vitamin D, thyroid hormone, and retinoic acid receptors (VDR, TR, and RAR, respectively). In this work, the authors report high-resolution localization of the human RXR genes within cytogenetic bands and also within a standard reference map of cosmid DNA markers on human chromosomes. They have determined the location of the human RXR genes by pairwise hybridization of the RXR cosmids and reference markers, using fluorescence in situ hybridization. They localized (i) RXR[alpha] (RXRA) to chromosome 9 band q34.3; (ii) RXR[beta] (RXRB) to chromosome 6 band 21.3; and (iii) RXR[gamma] (RXRG) to chromosome 1 band q22-q23. Six retinoid-responsive transcription factors have been identified so far, including three retinoic acid receptors in addition to the three ...
Donnan dialysis with ion-exchange membranes was studied under various kinds of experimental conditions using ions of different valences. The diffusion coefficients (D{sub d}) of various kinds of ions in the ion-exchange membrane were obtained by curve fitting an equation derived from the mass balance to three kinds of Donnan dialytic experiments. It was found that the value of D{sub d}/D{sub s} using D{sub d} of monovalent ions in Donnan dialysis with a set of monovalent feed ions and bivalent driving ions was 1/175, where D{sub s} represents a diffusion coefficient in solution. D{sub s} was calculated from the Nernst-Einstein equation substituted by the ionic conductance of ions at infinite dilution in water. Using D{sub d} of bivalent ions in Donnan dialysis with the same set led to a D{sub d}/D{sub s} value of 1/438. Moreover, using D{sub d} in Donnan dialysis with the same set, the value of D{sub d}/D{sub e} was kept ...
The change of the transport coefficient due to the fusion energy source is studied. The scale invariance property of the reduced set of equations is investigated in the presence of the self-heating term due to the fusion reaction. The pressure gradient as well as the fusion power are the free energy sources that dictate the turbulent transport. It is shown that the burning transport coefficient can have a form with much wider variety, and that the transport property could be different owing to the self-heating by the fusion reactions. (author)
The effect of nuclear scattering on the suprathermal fusion probability of recoiling d-t nuclei under the impact of fusion products, a 14.1-MeV neutron and a 3.5 MeV alpha particle, in thick pellets is investigated with the help of the Boltzmann-Fokker-Planck equation. Although the suprathermal fusion from alpha-particle recoils is quite small, the one originating from neutron recoils is considerable.
An attempt is made to estimate the lithium reserve (the economically recoverable lithium) for the tritium breeding in D-T fusion reactors and other uses. Similar development patterns for fusion energy and fission energy are assumed to estimate the future lithium requirements. These requirements are grouped into three categories; the commercial uses, the lithium batteries for electric cars, and the fusion reactor uses. 5 refs.
The Fusion Technology task performs analyses and systems studies of conceptual fusion reactors based upon inertial and high-#beta# magnetic confinement schemes. Progress in the areas of theoretical analysis (plasma and neutral-gas blanket models), specific reactor studies (toroidal and linear theta pinches, Z pinches, laser fusion) neutronic and nuclear data assessments, materials (metals and insulators) evaluation, and general engineering design is reported.
Conceptual fusion reactor studies over the past 10-15 yr have projected systems that may be too large, complex, and costly to be of commercial interest. One main direction for improved fusion reactors points toward smaller, higher-power-density approaches. First-order economic issues (i.e., unit direct cost and cost of electricity) are used to support the need for more compact fusion reactors. The results of a number of recent conceptual designs of reversed-field pinch, spheromak, and tokamak fusion reactors are summarized as examples of more compact approaches. While a focus has been placed on increasing the fusion-power-core mass power density beyond the minimum economic threshold of 100-200 kWe/tonne, other means by which the overall attractiveness of fusion as a long-term energy source are also addressed.
An almost primordial trend in the conversion and use of energy is an increased complexity and cost of conversion systems designed to utilize cheaper and more-abundant fuels; this trend is exemplified by the progression fossil fission {yields} fusion. The present projections of the latter indicate that capital costs of the fusion ``burner`` far exceed any commensurate savings associated with the cheapest and most-abundant of fuels. These projections suggest competitive fusion power only if internal costs associate with the use of fossil or fission fuels emerge to make them either uneconomic, unacceptable, or both with respect to expensive fusion systems. This ``implementation-by-default`` plan for fusion is re-examined by identifying in general terms fusion power-plant embodiments that might compete favorably under conditions where internal costs (both economic ...
Fusion energy has been studied in many countries such as U.S., France, Japan, Korea etc. Because it would provide much more energy for a given weight of fuel than any technology currently in use, and the fuel itself (primarily deuterium) exists abundantly in the Earth's ocean. Nuclear fusion reactor uses tritium and deuterium as fuel while nuclear fission reactor uses uranium and plutonium as fuel. Besides, inherent design characteristics and driving condition of nuclear fusion reactor is different from those of nuclear fission reactor. Therefore, we cannot apply the regulation rules of nuclear fission reactor to nuclear fusion reactor without change and thus it is needed to development of the safety regulation concept which reflects the characteristics of nuclear fusion reactor. Safety regulation of nuclear fusion reactor employs deterministic approach until ...
Fusion energy is one of only a few truly long-term energy options. Since its inception in the 1950s, the vision of the fusion energy research program has been to develop a viable means of harnessing the virtually unlimited energy stored in the nuclei of light atoms--the primary fuel deuterium is present as one part in 6,500 of all hydrogen. This vision grew out of the recognition that the immense power radiated by the sun is fueled by nuclear fusion in its hot core. Such high temperatures are a prerequisite for driving significant fusion reactions. The fascinating fourth state of matter at high temperatures is known as plasma. It is only in this fourth state of matter that the nuclei of two light atoms can fuse, releasing the excess energy that was needed to separately bind each of the original two nuclei. Because the nuclei of atoms carry a net positive electric charge, they repel each other. ...
The Second International Workshop on Human Chromosome 9 was held in Chatham, Massachusetts on April 18--20, 1993. Fifty-three abstracts were received and the data presented on posters. The purpose of the meeting was to bring together all interested investigators working on the map of chromosome 9, many of whom had disease-specific interests. After a brief presentation of interests and highlighted results, the meeting broke up into the following subgroups for production of consensus maps: 9p; 9cen-q32; 9q32 ter. A global mapping group also met. Reports of each of these working groups is presented in the summary.
Human BTEB cDNA clones have been isolated, sequenced, and the corresponding gene has been assigned to human chromosome 9, region q13, by fluorescent in situ hybridization and DNA blot analysis using DNAs from hybrid cell clones containing a single human chromosome. The cDNA clone encodes a polypeptide of 244 amino acids whose sequence shows a high sequence similarity with the rat BTEB (98% amino acid identity).
Recent studies have shown Y chromosome microdeletions associated with male infertility. The factors responsible for Y chromosome microdeletions in spermatozoa remain unresolved. However, the environmental pollutants are known to damage DNA in differentiating and maturing germ cells in the male reproductive tract. Therefore, the aim of this study was to investigate the effects of seminal hexachlorocyclohexane (HCH) and its isomers, an environmental pollutant, in 50 fertile and 50 infertile males in relation to semen quality and the incidence of Y chromosome microdeletion in azoospermic factor (AZF) region. As compared to control, an increased HCH level and significantly decreased semen quality were observed in the infertile males. A positive significant association was found between sperm c...
Telomeres protect the chromosome ends from unscheduled DNA repair and degradation. Telomeres are heterochromatic domains composed of repetitive DNA (TTAGGG repeats) bound to an array of specialized...Full Text Available
Lentiviral vectors enter cells with high efficiency and deliver stable transduction through integration into host chromosomes, but their preference for integration within actively transcribing genes...Full Text Available
Eukaryotic genomes are packaged in two basic forms, euchromatin and heterochromatin. We have examined the composition and organization of Drosophila melanogaster heterochromatin in...Full Text Available
The expression of motor activity levels in response to novel situations is under complex genetic and environmental control. Several genetic loci have been implicated in the regulation of this behavioral phenotype, but their relationship to epigenetic and epistatic interactions is relatively unknown. Here, we report on a quantitative trait locus (QTL) on mouse chromosome 1 for novelty-induced motor activity in the open field, using chromosome substitution strains derived from a high active host strain (C57BL/6J) and a low active donor strain (A/J). The QTL for open field (horizontal distance moved) peaked at the location of Kcnj9, however, QTL detection was initially masked by an interplay of both grandparent genetic origin and genetic co-factors influencing behavior on chromosome 1. Our fi...
Males and females display differences in physiology, behaviour and susceptibility to many diseases. Genome-wide transcription profiling studies have uncovered large-scale sex differences in autosomal gene expression in somatic tissues that are thought to underlie such 'sexual dimorphisms'. Because males and females differ genetically mainly in their sex chromosome complement, most sex differences can be traced back to the X and Y chromosomes. Although sex hormones are usually considered the main architects of sexual dimorphisms, recent studies have demonstrated that sex chromosomes can also induce sex differences in somatic gene expression in the absence of hormonal differences. The recent discovery of epigenetic sex differences that are not hormone-induced brings us closer to understandin...
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Several scientists have proposed that DNA repair deficiencies and the induction of a mutator phenotype are responsible for the generation of multiple mutagenic alterations in cancer cells. I propose...Full Text Available
We present an experimental study of vesicle fusion using light and neutron scattering to monitor fusion events. Vesicles are reproducibly formed with an extrusion procedure using an single amphiphile triethylene glycol mono-n-decyl ether in water. They show long-term stability for temperatures around 20 C, but at temperatures above 26 C we observe an increase in the scattered intensity due to fusion. The system is unusually well suited for the study of basic mechanisms of vesicle fusion. The vesicles are flexible with a bending rigidity of only a few k(H)T. The monolayer spontaneous curvature, Ho, depends strongly on temperature in a known way and is thus tunable. For temperatures where H-0 > 0 vesicles tyre long-term stable, while in the range H-0 < 0 the fusion rate increases the more negative the Spontaneous curvature Through a quantitative;analysis of the ...
We carry out investigation on the establishment of a program to cultivate a nuclear fusion workforce effectively, which is the most important resource in the fusion energy development. Acquisition of fresh fusion technologies is essentially required to pursue R and D efficiently and to ensure fusion initiatives firmly in the international community. As the time has come to cultivate the fusion workforce and to enhance the workforce's expertise, the universities, research institutes and industries involved in fusion energy development are supposed to adjust fast technology shifts and to accommodate international trends toward collaboration. We establish systematic schemes to develop a professional workforce and to assign the right jobs to the right people timely through the research-academic-industry cooperation. After carrying out domestic and oversea ...
The Screening Risk Evaluation (SRE) guidance document is a set of guidelines provided for the uniform implementation of SREs performed on decontamination and decommissioning (D&D) facilities. Although this method has been developed for D&D facilities, it can be used for transition (EM-60) facilities as well. The SRE guidance produces screening risk scores reflecting levels of risk through the use of risk ranking indices. Five types of possible risk are calculated from the SRE: current releases, worker exposures, future releases, physical hazards, and criticality. The Current Release Index (CRI) calculates the current risk to human health and the environment, exterior to the building, from ongoing or probable releases within a one-year time period. The Worker Exposure Index (WEI) calculates the current risk to workers, occupants and visitors inside contaminated D&D facilities due to contaminant exposure. The ...
We prove a generalization of the Verlinde formula to fermionic rational conformal field theories. The fusion coefficients of the fermionic theory are equal to sums of fusion coefficients of its bosonic projection. In particular, fusion coefficients of the fermionic theory connecting two conjugate Ramond fields with the identity are either one or two. Therefore, one is forced to weaken the axioms of fusion algebras for fermionic theories. We show that in the special case of fermionic W(2, #delta#)-algebras these coefficients are given by the dimensions of the irreducible representations of the horizontal subalgebra on the highest weight. As concrete examples we discuss fusion algebras of rational models of fermionic W(2, #delta#)-algebras including minimal models of the N = 1 super Virasoro algebra as well as N = 1 super W-algebras SW(3/2, #delta#). (orig.).
Genomic instability can be produced by ionising radiation, so-called radiation-induced genomic instability, and chemical mutagens. Radiation-induced genomic instability occurs in both germinal and somatic cells and also in the offspring of irradiated individuals, and it is characterised by genetic changes including chromosomal rearrangements. The majority of studies of trans-generational, radiation-induced genomic instability have been described in the male germ line, whereas the authors who have chosen the female as a model are scarce. The aim of this work is to find out the radiation-induced effects in the foetal offspring of X-ray-treated female rats and, at the same time, the possible impact of this radiation-induced genomic instability on the action of a chemical mutagen. In order to achieve both goals, the quantity and quality of chromosomal damage were analysed. In order to detect trans-generational genomic instability, a total of 4806 ...
A hallmark of several human cancers is loss of heterozygosity (LOH) of chromosome 17p13. The same chromosomal region is also frequently hypermethylated in cancer. Although loss of 17p13 has been often...Full Text Available
Lethal alleles of the Drosophila k43 gene result in small or missing imaginal discs, greatly reduced mitotic index, and fragmented and abnormally condensed chromosomes. A female-sterile...Full Text Available
We have isolated and sequenced cDNA clones encoding the human U1-70K snRNP protein, and have mapped this locus (U1AP1) to human chromosome 19. The gene produces two size classes of RNA, a major 1.7-kb...Full Text Available
Staphylococcal cassette chromosome mec (SCCmec) is a mobile genetic element characterized by flanking terminal direct and, in most cases, inverted repeat sequences,...Full Text Available
Genome sequences are essential tools for comparative and mutational analyses. Here we present the short read sequence of mouse chromosome 17 from the Mus musculus domesticus derived...Full Text Available
A chromosome-encoded β-lactamase gene, cloned and expressed in Escherichia coli from Kluyvera georgiana reference strain CUETM 4246-74 (DSM 9408), encoded the...Full Text Available
Utilizing the CEPH reference panel and genotypic data for 53 markers, we have constructed a 20-locus multipoint genetic map of human chromosome 4. New RFLPs are reported for four loci. The map integrates...Full Text Available
The hemagglutinin (HA) glycoprotein of influenza virus performs two critical roles during infection: it binds virus to cell surface sialic acids, and under mildly acidic conditions it induces fusion...Full Text Available
Select members of the Reoviridae are the only nonenveloped viruses known to induce syncytium formation. The fusogenic orthoreoviruses accomplish cell-cell fusion through a distinct...Full Text Available
The fusogenic orthoreoviruses express nonstructural fusion-associated small transmembrane (FAST) proteins that induce cell-cell fusion and syncytium formation. It has been speculated that the FAST proteins...Full Text Available
The Senior Committee on Environmental, Safety, and Economic Aspects of Magnetic Fusion Energy (ESECOM) has assessed magnetic fusion energy's prospects for providing energy with economic, environmental, and safety characteristics that would be attractive compared with other energy sources (mainly fission) available in the year 2015 and beyond. ESECOM gives particular attention to the interaction of environmental, safety, and economic characteristics of a variety of magnetic fusion reactors, and compares them with a variety of fission cases. Eight fusion cases, two fusion-fission hybrid cases, and four fission cases are examined, using consistent economic and safety models. These models permit exploration of the environmental, safety, and economic potential of fusion concepts using a wide range of possible materials choices, power densities, power ...
This report discusses the following topics: Fusion-fission in light nuclear systems; High-resolution Q-value measurement for the {sup 24}Mg+{sup 24}Mg reaction; Heavy-ion reactions and limits to fusion; and Hybrid MWPC-Bragg curve detector development.
The calculated radioactive waste inventories of the Turkey Point pressurized water fission reactor (PWR) and the Starfire conceptual fusion tokamak are compared as a function of time from initial start-up to 10,000 years after decommissioning. Only materi...
To gain insight into the process of mitochondrial transmission in yeast, we directly labeled mitochondrial proteins and mitochondrial DNA (mtDNA) and observed their fate after the fusion of two cells....Full Text Available
Two heterologous expression systems using thioredoxin (trxA) as a gene fusion part in Escherichia coli were developed to produce recombinant pediocin PA-1. Pediocin...Full Text Available
A generic reactor model is used to examine the economic viability of electricity generation by magnetic fusion. The simple model uses components which are representative of those used in previous reactor studies of deuterium-tritium burning tokamaks, stellarators, bumpy tori, reverse field pinches and tandem mirrors. Conservative costing assumptions are made. The generic reactor is not a tokamak but rather it is intended to emphasize what is common to all magnetic fusion reactors. The reactor uses a superconducting toroidal coil set to produce the dominant magnetic field. To this extent it is a less good approximation to systems, such as the reversed field pinch in which the main field is produced by a plasma current. The main output of the study is the cost of electricity as a function of the weight and size of the fusion core - blanket, shield, structure and coils. The model shows that a 1200 MW/sub e/ power plant with a ...
The existence and importance of an accelerated adjacent segment disc degeneration (ASD) after lumbar fusion have previously not been demonstrated by RCTs. The objectives of this study were, to determine...Full Text Available
The human smooth muscle myosin heavy chain locus (MYH11) was mapped by fluorescence in situ hybridization to the middle of the p arm of chromosome 16 using a genomic cosmid clone containing coding sequences of the gene as probe. Probe from coding sequence, when applied to Southern blots of a panel of hybrids containing different portions of human chromosome 16, localized the gene to 16p13.13-13.12. Coding sequence PCR primers, when used on the DNA from a CHO-mouse hybrid clone mapping panel informative for mouse chromosomes, showed that the gene was located on mouse chromosome 16. These results correct a recent assignment of MYH11 from 16q12.2 to the region of the 16p-arm inversion breakpoint seen in acute myelomonocytic leukemia (AMML) M4Eo and demonstrate that the conflicting data do not result from the presence of additional MYH genes on the q arm of the chromosome. Also, a new ...
It has recently been found that many buildings in Taiwan were constructed with radioactively contaminated rebar, which raised great concern among the residents as well as governmental officials. In order to investigate the possible cytogenetic damage to the residents of contaminated buildings, a G-banding method was carried out on the lymphocytes of 30 radiation-exposed individuals from four families and one office building, as well as 15 control individuals from laboratory personnel. The estimated cumulative radiation doses for the exposed people range from 19.63 to 280.50 mSv. Altogether, 13 females and 17 males belonging to the radiation-exposed group, and 7 females and 8 males in the control group, were included in this study. With the exception of one sample, at least 500 metaphase spreads were scored and analyzed for each individual. All the recognizable structural aberrations of chromosomes or chromatids were recorded and statistically analyzed. Comparison ...
It has recently been found that many buildings in Taiwan were constructed with radioactively contaminated rebar, which raised great concern among the residents as well as governmental officials. In order to investigate the possible cytogenetic damage to the residents of contaminated buildings, a G-banding method was carried out on the lymphocytes of 30 radiation-exposed individuals from four families and one office building, as well as 15 control individuals from laboratory personnel. The estimated cumulative radiation doses for the exposed people range from 19.63 to 280.50 mSv. Altogether, 13 females and 17 males belonging to the radiation-exposed group, and 7 females and 8 males in the control group, were included in this study. With the exception of one sample, at least 500 metaphase spreads were scored and analyzed for each individual. All the recognizable structural aberrations of chromosomes or chromatids were recorded and statistically analyzed. Comparison ...
To estimate the waste management needs of a fusion power reactor, a scheme for handling radioactive waste from a fusion plant has been devised. The handling scheme proceeds with radioactive waste, primarily from blanket replacement, being stored on-site; waste in cooled and shielded casks is then isolated off-site; finally, the materials are recycled. Using activities and component lifetimes supplied by designers, several conceptual fusion power reactors have been analyzed and their waste streams compared to fission reactors with regard to total activity, specific activity, and lifetimes of activity.
To estimate the waste management needs of a fusion power reactor, a scheme for handling radioactive waste from a fusion plant has been devised. The handling scheme proceeds with radioactive waste, primarily from blanket replacement, being stored on-site; waste in cooled and shielded casks is then isolated off-site; finally, the materials are recycled. Using activities and component lifetimes supplied by designers, several conceptual fusion power reactors have been analyzed and their waste streams compared to fission reactors with regard to total activity, specific activity, and lifetimes of activity.
The conceptual design of an ohmically heated, reversed-field pinch (RFP) operating at /approximately/5-MW/m/sup 2/ steady-state DT fusion neutron wall loading and /approximately/124-MW total fusion power is presented. These results are useful in projecting the development of a cost effective, low input power (/approximately/206 MW) source of DT neutrons for large-volume (/approximately/10 m/sup 3/), high-fluence (3.4 MW yr/m/sup 2/) fusion nuclear materials and technology testing. 19 refs., 15 figs., 9 tabs.
... in the design of such devices as fusion reactors, magnetohydrodynamic generators, magnetically levitated vehicles, magnetic forming devices, and ...
... such as discovery, capabilities registration, lookup, and a ... Java- based toolkit for creating ... Multisensor, Multisource Information Fusion: Architectures ...
The maximum fissile fuel production capacity of three conceptual fusion breeder systems is examined on the basis of the dominant isotopic-balance processes. Compact relationships involving system power output, plasma and energy multiplication, and parameters which describe the fuel cycle and neutron spectrum in the blanket are established. It is found that the fusion breeder, as characterized herein, possesses a substantial fissile fuel breeding capacity the extent of which is governed primarily by the neutron spectrum in the conversion blanket and the break-even condition of the plasma.
BackgroundThe pre-fusion form of the herpes simplex virus (HSV) fusion protein gB undergoes pH-triggered conformational change in vitro and during viral entry (Dollery...Full Text Available
The heat capacity and heat of fusion were measured for a number of minerals using differential scanning calorimetry (DSC). The DSC measurements showed that the heat of fusion for the minerals is very low compared to the heat of fusion for pure crystalline phases reported elsewhere. A model for the melting behaviour of mineral materials in terms of melting interval, heat capacities and heat of fusion has been developed. The only model input is the chemical composition of the mineral material. The model was developed to be implemented in a detailed model of a cupola furnace, thus the focus for the development was not only precision but also to obtain a model that was continuous and differentiable. The model is based on several different submodels that each covers a part of the heating and melting of rocks. Each submodel is based on large amounts of empirical data. Comparison of the model and the DSC ...
A linear induction accelerator that produces a beam of energetic heavy ions (T -- 10 GeV, A -- 200 amu) is a prime candidate as a driver for an inertial fusion power plant. Some early perceptions were that heavy-ion drive fusion would not be cost-competitive with other power sources because of the high cost of the accelerators. However, improved understanding of the physics of heavy-ion transport and acceleration (supported by experimental results), combined with advances in accelerator technology, have resulted in accelerator design costs -- 50% of previous estimates. As a result, heavy-ion drive fusion power plants are now projected to be cost-competitive with other conceptual fusion power plants. A brief formulation of transport and acceleration physics is presented here, along with a description of the induction Linac cost optimization code LIACEP. Cost trends are presented and discussed, along with ...
A linear induction accelerator that produces a beam of energetic heavy ions (T #approx =# 10 GeV, A #approx =# 200 am#mu#) is a prime candidate as a driver for an inertial fusion power plant. Some early perceptions were that heavy-ion driven fusion would not be cost-competitive with other power sources because of the high cost of the accelerators. However, improved understanding of the physics of heavy-ion transport and acceleration (supported by experimental results), combined with advances in accelerator technology, have resulted in accelerator design costs -- 50% of previous estimates. As a result, heavy-ion driven fusion power plants conceptual fusion power plants. A brief formulation of transport and acceleration physics is presented here, along with a description of the induction Linac cost optimization code LIACEP. Cost trends are presented and discussed, along with specific cost estimates for ...
Environmental characteristics of conceptual fusion-reactor systems based on magnetic confinement are examined quantitatively, and some comparisons with fission systems are made. Fusion, like all other energy sources, will not be completely free of environmental liabilities, but the most obvious of these-- tritium leakage and activation of structural materials by neutron bombardment-- are susceptible to significant reduction by ingenuity in choice of materials and design. Large fusion reactors can probably be designed so that worst-case releases of radioactivity owing to accident or sabotage would produce no prompt fatalities in the public. A world energy economy relying heavily on fusion could make heavy demands on scarce nonfuel materials, a topic deserving further attention. Fusion's potential environmental advantages are not entirely ...
The infection of cultured human cells with baboon endogenous virus (BEV) frequently leads to an association of viral DNA with a specific genetic locus (termed BEVI, for baboon endogenous virus infection) on chromosome 6. Restriction endonuclease digestion of DNA from BEV-infected human cells and their derived somatic cell clones frequently revealed a common cellular DNA sequence in the proximity of one of the junctions between cellular DNA and the integrated virus. We propose that a short cellular DNA sequence, repeated on chromosome 6 and separated by unique DNA sequences, presents a high-affinity target for the integration of BEV in human cells. PMID:6401843
The 50th anniversary of Mary Lyon?s 1961 Nature paper, proposing random inactivation in early embryonic life of one of the two X chromosomes in the cells of mammalian females, provides an opportunity to remember and celebrate the work of those involved. While the hypothesis was initially put forward by Lyon based on findings in the mouse, it was founded on earlier studies, notably the work of Susumu Ohno; it was also suggested independently by Beutler and colleagues using experimental evidence from a human X-linked disorder, glucose-6-phosphate dehydrogenase deficiency, and has proved to be of as great importance for human and medical genetics as it has for general mammalian genetics. Alongside the hypothesis itself, previous cytological studies of mouse and human chromosomes, and the obse...
A 4.0 kb TaqI fragment of cosmid EFD64 isolated by a HBV-3 oligonucleotide was subcloned into AccI site of pUC18. MspI identifies 5 allelic VNTR polymorphism with bands between 2.6 and 4.6 kb. RsaI, TaqI, EcoRI, BamHI, HindIII and PvuII identify the same VNTR polymorphism. With RsaI, 80% heterozygosity were observed in 80 unrelated Caucasians. This RFLP pEFD64.2 has been assigned to chromosome 3 by linkage analysis with loci (APOD) known to span this chromosome. Co-dominant segregation for the RsaI RFLP was observed in 40 three generation families. RFLPs were observed under the normal hybridization and washing condition.
In the post Genome era, the aim of behavior genetics has shifted from estimating the relative contributions of genes and environmental factors to (co-)variation in human complex traits, to localization of genes and identification of functional genetic variants. This special issue reflects this transition and presents fifteen papers that report on genome-wide linkage scans for complex traits in humans and on methodological tools and innovations. Six papers focus on cognition and report overlapping linkage peaks on chromosomes 6p and 14p. Papers on addictive behavior, i.e. smoking and alcohol dependence and its endophenotypes, find moderate LOD scores on chromosomes 6p, 5q, 4p and 7q, respectively. Three papers concentrate on emotionality, depression and loneliness and examine chromosomes 2q...
Prepulse inhibition (PPI) is a measure of sensorimotor gating, a pre-attentional inhibitory brain mechanism that filters extraneous stimuli. Prepulse inhibition is correlated with measures of cognition and executive functioning, and is considered an endophenotype of schizophrenia and other psychiatric illnesses in which patients show PPI impairments. As a first step toward identifying genes that regulate PPI, we performed a quantitative trait locus (QTL) screen of PPI phenotypes in a panel of mouse chromosome substitution strains (CSSs). We identified five CSSs with altered PPI compared with the host C57BL/6J strain: CSS-4 exhibited decreased PPI, whereas CSS-10, -11, -16 and -Y exhibited higher PPI compared with C57BL/6J. These data indicate that A/J chromosomes 4, 10, 11, 16 and Y harbor...
Abstract Routinely used prognostic factors fail to predict clinical outcome in a significant proportion of breast cancer patients, implying that they can not detect some important biological characteristics. Chromosomal changes have been described in breast carcinomas for many years but their significance is not clear. We compared chromosomal changes with clinico-pathological characteristics and clinical outcome in 203 breast cancer patients with a follow-up of 9-18 years. Combining data from classical cytogenetics and flow cytometry revealed chromosomal abnormalities in 142 cases (70%). Of these, 51 (35.9%) contained two or more cytogenetically abnormal clones. Polyclonality was significantly associated with poor breast-cancer-specific survival (P = 0.03) within 5 years, independent of tu...
In eukaryotes, accurate chromosome segregation during mitosis and meiosis is coordinated by kinetochores, which are unique chromosomal sites for microtubule attachment. Centromeres specify the kinetochore formation sites on individual chromosomes, and are epigenetically marked by the assembly of nucleosomes containing the centromere-specific histone H3 variant, CENP-A. Although the underlying mechanism is unclear, centromere inheritance is probably dictated by the architecture of the centromeric nucleosome. Here we report the crystal structure of the human centromeric nucleosome containing CENP-A and its cognate ?-satellite DNA derivative (147 base pairs). In the human CENP-A nucleosome, the DNA is wrapped around the histone octamer, consisting of two each of histones H2A, H2B, H4 and CENP...
An economic analysis of the potential advantages of alternatives for recycling and reusing equipment now stored in Building 865 at the Rocky Flats Plant (RFP) in Colorado has been conducted. The inventory considered in this analysis consists primarily of metallurgical and process equipment used before January 1992, during development and production of nuclear weapons components at the site. The economic analysis consists of a thorough building inventory and cost comparisons for four equipment dispositions alternatives. The first is a baseline option of disposal at a Low Level Waste (LLW) landfill. The three alternatives investigated are metal recycling, reuse with the government sector, and release for unrestricted use. This report provides item-by-item estimates of value, disposal cost, and decontamination cost. The economic evaluation methods documented here, the simple cost comparisons presented, and the data provided as a supplement, should provide a foundation for ...
With major D&D projects ongoing or being planned, and also with the daily management of radwaste from nuclear facilities, the potential role of transport packagings has often been overlooked: here will one rely essentially on drums, there several local waste processing units are built, elsewhere decommissioned facilities are cut in small bits to fit into small containers by far less efficient. The present paper proposes to illustrate how integrating a transport system from the start may influence operational choices of waste management.
The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects ...
The activation aspects of pure fusion and hybrid fusion technology is studied to assess the radioactive safety of various fusion concepts including tokamak pure fusion, fissile fuel producing hybrid and radio waste transmuting hybrid. The activation properties of breeding, coolant and structural materials in fusion reactors might be quite different from those in fission reactors because of the high energy D-T fusion neutrons from the fusion cores. A study on the involved activation reactions and the uncertainties of the associated nuclear cross-sections is carried. The activation properties of various first wall concepts and blanket concepts are discussed. The radioactive inventory during the operation lifetime and the potential hazard of the radioactive nuclides with respect to near term (reprocessing) and long term (waste disposal) aspects ...
The genes which encode glycosomal glyceraldehyde-phosphate dehydrogenase (gGAPDH) of Trypanosoma cruzi are arranged as a tandemly repeated pair on a single chromosome and are identical at the level...Full Text Available
The mini-chromosome maintenance proteins Mcm2–7 are essential for DNA replication. They are loaded onto replication origins during G1 phase of the cell cycle to form a pre-replication complex...Full Text Available
Mouse genetic resources include inbred strains, recombinant inbred lines, chromosome substitution strains, heterogeneous stocks, and the Collaborative Cross (CC). These resources were generated through...Full Text Available
BackgroundChromatin insulators or boundary elements are a class of functional elements in the eukaryotic genome. They regulate gene transcription by interfering with promoter-enhancer...Full Text Available
By analysis of crossovers in key recombinant families and by homozygosity analysis of inbred families, the Friedreich ataxia (FRDA) locus was localized in a 300-kb interval between the X104 gene and...Full Text Available
Hepatitis B virus (HBV) is clearly a factor in the development of hepatocellular carcinoma, but its mechanism of action remains obscure. One possibility is that the HBV integration event alters the...Full Text Available
Recognition of acetylated chromatin by the bromodomains and extra-terminal domain (BET) family proteins is a hallmark for transcriptional activation and anchoring viral genomes to mitotic chromosomes...Full Text Available
Using the complete genome of Plasmodium falciparum 3D7 which has 14 chromosomes as an example, we have examined the distribution functions for the amount of C or G and A or T consecutively...Full Text Available
BackgroundRecent evidence suggests that some sex differences in brain and behavior might result from direct genetic effects, and not solely the result of the organizational effects...Full Text Available
Human chromosomal fragile sites are specific loci that are especially susceptible to DNA breakage following conditions of partial replication stress. They often are found in genes involved in tumorigenesis...Full Text Available
A regulatory locus on the Staphylococcus aureus chromosome, designated sar, is involved in the expression of cell wall proteins, some of which are potentially important in the pathogenesis of endocarditis....Full Text Available
BackgroundEukaryotic DNA replication is regulated at the level of large chromosomal domains (0.5–5 megabases in mammals) within which replicons are activated relatively synchronously....Full Text Available
Hepatitis B virus (HBV) DNA integration has been shown to occur frequently in human hepatocellular carcinomas. We have investigated whether common cellular DNA domains might be rearranged, possibly...Full Text Available
Hepatitis B virus (HBV) DNA integration has been shown to occur frequently in human hepatocellular carcinomas. The authors have investigated whether common cellular DNA domains might be rearranged, possibly by HBV integration, in human primary liver tumors. Unique cellular DNA sequences adjacent to an HBV integration site were isolated from a patient with hepatitis B surface antigen-positive hepatocellular carcinoma. These probes detected rearrangement of this cellular region of chromosomal DNA in 3 of 50 additional primary liver tumors studied. Of these three tumor samples, two contained HBV DNA, without an apparent link between the viral DNA and the rearranged allele; HBV DNA sequences were not detected in the third tumor sample. By use of a panel of somatic cell hybrids, these unique cellular DNA sequences were shown to be located on chromosome 4. Therefore, this region of chromosomal DNA might be implicated in the ...
Hepatitis B virus (HBV) DNA integration has been shown to occur frequently in human hepatocellular carcinomas. The authors have investigated whether common cellular DNA domains might be rearranged, possibly by HBV integration, in human primary liver tumors. Unique cellular DNA sequences adjacent to an HBV integration site were isolated from a patient with hepatitis B surface antigen-positive hepatocellular carcinoma. These probes detected rearrangement of this cellular region of chromosomal DNA in 3 of 50 additional primary liver tumors studied. Of these three tumor samples, two contained HBV DNA, without an apparent link between the viral DNA and the rearranged allele; HBV DNA sequences were not detected in the third tumor sample. By use of a panel of somatic cell hybrids, these unique cellular DNA sequences were shown to be located on chromosome 4. Therefore, this region of chromosomal DNA might be implicated in the ...
Some cases of autism spectrum disorder (ASD) have mutations in the lipid phosphatase, Pten (phosphatase and tensin homolog on chromosome 10). Tissue...Full Text Available
Mapping the restriction fragments of the Brucella melitensis 16M genome with a new restriction endonuclease, PacI, which cut the DNA into only eight fragments, indicated that this species contains two...Full Text Available
BackgroundAurora kinases play an essential role in orchestrating chromosome alignment, segregation and cytokinesis during mitotic progression, with both aurora-A and B frequently...Full Text Available
PurposeThe size of neuronal populations is modulated by gene variants that influence cell production and survival, in turn influencing neuronal connectivity, function,...Full Text Available
Pancreatitis-associated protein (PAP) is a secretory pancreatic protein present in small amounts in normal pancreas and overexpressed during the acute phase of pancreatitis. In this paper, the authors describe the cloning, characterization, and chromosomal mapping of the human PAP gene. The gene spans 2748 bp and contains six exons interrupted by five introns. The gene has a typical promoter containing the sequences TATAAA and CCAAT 28 and 52 bp upstream of the cap site, respectively. They found striking similarities in genomic organization as well as in the promoter sequences between the human and rat PAP genes. The human PAP gene was mapped to chromosome 2p12 using rodent-human hybrid cells and in situ chromosomal hybridization. This localization coincides with that of the reg/lithostathine gene, which encodes a pancreatic secretory protein structurally related to PAP, suggesting that both genes derived from the same ...
Oryza sativa or Asian cultivated rice is one of the major cereal grass species domesticated for human food use during the Neolithic. Domestication of this species from the wild grass...Full Text Available
Cdc13 is a single stranded telomere binding protein that specifically localizes to the telomere ends of budding yeasts and is essential for cell viability. It caps the ends of chromosomes thus preventing...Full Text Available
Chromosomal common fragile sites (CFSs) are genetically unstable regions of the genome that are induced by conditions that impair DNA replication. In this report, we show that treatment with the DNA...Full Text Available
The plasmid pE194 (3.7 kilobases) is capable of integrating into the genome of the bacterial host Bacillus subtilis in the absence of the major homology-dependent RecE recombination system. Multiple...Full Text Available
Telomerase, a ribonucleoprotein enzyme that maintains telomere length, is crucial for cellular immortalization and cancer progression. Telomerase activity is attributed primarily to the expression of...Full Text Available
The genome sequence of the solvent-producing bacterium Clostridium acetobutylicum ATCC 824 has been determined by the shotgun approach. The genome consists of a 3.94-Mb chromosome and...Full Text Available
Previous research utilizing the AcB/BcA recombinant congenic strains (RCS) of mice mapped provisional quantitative trait loci (QTLs) for the psychostimulant effects of nicotine to multiple regions on chromosomes 7, 11, 12, 14, 16, and 17. The current study was designed to confirm these QTLs in an A/J (A)??C57Bl/6J (B6) F2 cross and a panel of B6.A chromosome substitution strains (CSS). The panel of B6.A CSS consists of 21 strains, each carrying a different A/J chromosome on a B6 background. The A??B6 F2, CSS, A, and B6 mice were tested for sensitivity to the effects of nicotine on locomotor activity using a computerized open-field apparatus. In A??B6 F2 mice two QTLs were identified which confirm those previously observed in the AcB/BcA RCS. Significant differences in the expression of ...
BackgroundSpecies with heteromorphic sex chromosomes face the challenge of large-scale imbalance in gene dose. Microarray-based studies in several independent male heterogametic...Full Text Available
It is generally accepted that mammalian oocytes are frequently suffering from chromosome segregation errors during meiosis I, which have severe consequences, including pregnancy loss, developmental...Full Text Available
Chromosomal translocation, deletion, and inversion/duplication directly linked to hepatitis B virus (HBV) DNA integration occur frequently in host DNA of human hepatocellular carcinomas. To test the...Full Text Available
BackgroundEscherichia coli strain EL350 contains chromosomally integrated phage lambda Red recombinase genes enabling this strain to be used for modifying the sequence...Full Text Available
SummaryDnaA initiates chromosomal replication in E. coli at a well regulated time in the cell-cycle. To determine how the spatial distribution of DnaA is related...Full Text Available
BackgroundSeven genes involved in folate metabolism are located on chromosome 21. Previous studies have shown that folate deficiency may contribute to mental retardation in Down's...Full Text Available
SpoIIIE is an FtsK-related protein that transports the forespore chromosome across the Bacillus subtilis sporulation septum. We use membrane photobleaching and protoplast assays to...Full Text Available
Uncoupling protein 2 (UCP2) maps to a region on distal mouse chromosome 7 that has been linked to the phenotypes of obesity and type II diabetes. We recently reported that UCP2 expression is increased...Full Text Available
Cyteogenetic maps of sorghum chromosomes 3-7, 9, and 10 were constructed on the basis of the fluorescence in situ hybridization (FISH) of ~ ... regions of heterchromatin were delimited for all 10 sorghum chrom...
The two haploid genome sequences that a person inherits from the two parents represent the most fundamentally useful type of genetic information for the study of heritable diseases and the development...Full Text Available
Present investigations suggest that approximately 30% of colorectal cancer (CRC) cases arise on the basis of inherited factors. We hypothesize that the majority of inherited factors are moderately...Full Text Available
Two overlapping cDNA clones encoding human DNA topoisomerase II were identified by two independent methods. In one, a human cDNA library in phage {lambda} was screened by hybridization with a mixed oligonucleotide probe encoding a stretch of seven amino acids found in yeast and Drosophila DNA topoisomerase II; in the other, a different human cDNA library in a {lambda}gt11 expression vector was screened for the expression of antigenic determinants that are recognized by rabbit antibodies specific to human DNA topoisomerase II. The entire coding sequences of the human DNA topoisomerase II gene were determined from these and several additional clones, identified through the use of the cloned human TOP2 gene sequences as probes. Hybridization between the cloned sequences and mRNA and genomic DNA indicates that the human enzyme is encoded by a single-copy gene. The location of the gene was mapped to chromosome 17q21-22 by in situ hybridization of a cloned fragment to ...
The authors report the cloning, sequencing, and mapping of three short sequence repeat polymorphisms due to tetranucleotide (TAAA) repeats from human chromosome 21. These DNA markers (D21S221, D21S225, D21S226) have been cloned from the chromosome 21-specific plasmid library of J. C. Fuscoe, C. C. Collins, D. Pinkel, and J. W. Gray and were shown to be polymorphic by polymerase chain reaction amplification and polyacrylamide gel electrophoresis. Genotypes were determined in informative CEPH pedigrees and used in linkage analysis relative to other mapped markers on human chromosome 21. One of these markers, D21S221, is closely linked to the amyloid precursor protein gene (APP), which has been implicated in the etiology of familial Alzheimer disease in some families. 18 refs., 3 figs., 2 tabs.
In methicillin-resistant Staphylococcus aureus, the methicillin resistance gene mecA is localized within a large chromosomal region which is absent in the methicillin-susceptible...Full Text Available
The human CDC25 tyrosine phosphatases trigger activation of CDC2 by removing inhibitory phosphates; thus the genes encoding these phosphatases may be suspected as potential oncogenes due to their role in promoting cell division. To date, three human CDC25 genes have been identified: CDC25A, B, and C. This communication describes the mapping of CDC25A to chromosome 3p21 and CDC25B to chromosome 20p13 by fluorescence in situ hybridization with confirmation by the polymerase chain reaction of hamster-human somatic cell hybrid DNA. 3p21 is near an area frequently involved in karyotypic abnormalities in renal carcinomas, small cell carcinomas of the lung, and benign tumors of the salivary gland. 20p13 does not seem to be a common area for karyotypic alteration in tumors. Mapping of these genes to their chromosomal loci may help identify tumors with abnormal regulation of CDC25 genes due to genomic alterations. 15 refs., 3 figs.
Radiotherapy with high-energy carbon ion beams can be more advantageous compared to photons because of better physical dose distribution and higher biological efficiency in tumour cell sterilization. Despite enhanced normal tissue sparing, damage incurred by normal cells at the beam entrance is unavoidable and may affect the progeny of surviving cells in the form of inheritable cytogenetic alterations. Furthermore, the quality of the beam along the Bragg curve is modified by nuclear fragmentation of projectile and target nuclei in the body. We present an experimental approach based on the use of a polymethylmethacrylate (PMMA) phantom that allows the simultaneous exposure to a particle beam of several biological samples positioned at various depths along the beam path. The device was used to measure the biological effectiveness of a 60 MeV/amu carbon-ion beam at inducing chromosomal aberrations in G{sub 0}-human peripheral blood lymphocytes. ...
Germ cell tumor development in humans has been proposed to be part of testicular dysgenesis syndrome (TDS), which manifests as undescended testes, sterility, hypospadias, and, in extreme cases,...Full Text Available
The F1F0 ATPase of Vibrio alginolyticus was cloned from a chromosomal lambda library. The unc operon, which contains the structural genes for the ATPase, was sequenced and shown to have a gene organization...Full Text Available
DNA replication programs have been studied extensively in yeast and animal systems, where they have been shown to correlate with gene expression and certain epigenetic modifications. Despite the conservation...Full Text Available
BmpA, BmpB, BmpC, and BmpD are homologous Borrelia burgdorferi lipoproteins of unknown functions, encoded by the bmp genes of paralogous chromosomal gene family 36....Full Text Available
The human genome contains greater than 20 actin-related sequences, six of which at least are expressed as protein. We have shown by blot hybridization the presence of actin-like sequences on both the...Full Text Available
Background The objective of this study was to confirm provisional quantitative trait loci (QTL) for cocaine-induced locomotor activation, on chromosomes 1, 5, 6, 9, 12, 15, 16, 17, and 18, previously identified in the AXB/BXA recombinant inbred (RI) and AcB/BcA recombinant congenic (RC) strains of mice derived from A/J (A) and C57BL/6J (B6) progenitors. This was accomplished through a genetic analysis of cocaine-induced activity in an AxB6 F2 cross and a phenotypic survey across a panel of B6.A chromosome substitution strains (CSS) mice. Mice were tested for cocaine-induced activity, following administration of saline and cocaine (20?mg/kg), utilizing an open-field procedure. Results Among AxB6 F2 mice, differences in cocaine-induced activity were associated with loci on chromosome 1 (D1Mi...
Bacterial artificial chromosome (BAC) clones are effective mapping and sequencing reagents for use with a wide variety of small and large genomes. This report describes the development of a physical...Full Text Available
The paper describes a concept of extracting fusion power from D-{sup 3}He fueled IEC (Inertia Electrostatic Configuration) devices. The fusion system consists of a series of fusion modules and direct energy converters at an end or at both ends. This system of multiple units is linear and is connected by a magnetic field. A pair of coils anti-parallel to the magnetic field yields a field-null domain at the center of each unit as required for IEC operation. A stabilizing coil installed between the coil pairs eliminates the strong attractive force between the anti-parallel coils. Accessible regions for charged particle trajectories are essentially isolated from the coil structure. Thus, charged particles are directed along magnetic field lines to the direct energy converter without appreciable losses. A direct energy converter unit designed to be compatible to this unique system is also described. It basically consists of a ...
The maximum fissile fuel production capacity of three conceptual fusion breeder systems is examined on the basis of the dominant isotopic-balance processes. Compact relationships involving system power output, plasma and energy multiplication, and parameters which describe the fuel cycle and neutron spectrum in the blanket are established. It is found that the fusion breeder, as characterized herein, possesses a substantial fissile fuel breeding capacity the extent of which is governed primarily by the neutron spectrum in the conversion blanket and the break-even condition of the plasma. (author).
The thermonuclear reactivity of deuterium(D) - tritium(T) fusion plasma with spin-polarized fuel has been studied. Two mechanisms of depolarization, collisions and waves, in the high temperature fusion plasma have been considered. The binary collisions have been found not to change the nuclear spin states. The waves with a frequency of a few GHz, however, changes the spin states appreciably, when {delta}B/B{sub 0} (the ratio of the amplitude of the fluctuating magnetic field to the external field) becomes larger than 10{sup -5}. (author)
Solenoid transport of high current, heavy ion beams is considered for several stages of a heavy ion fusion driver. In general this option is more efficient than magnetic quadrupole transport at sufficiently low kinetic energy and/or large e/m, and for this reason it has been employed in electron induction linacs. Ideally an ion beam would be transported in a state of Brillouin flow, i.e. cold in the transverse plane and spinning at one half the cyclotron frequency. The design of appropriate solenoids and the equilibrium and stability of transported ion beams are discussed. An outline of application to a fusion driver is also presented.
The cold fusion reactions leading to superheavy elements with Z=104-116 has been discussed in our model recently [5]. Presently we shortly discuss our model and extend our consideration to fusion reactions ("8"6Kr, "8"7Rb, "8"8Sr)+"2"0"8Pb and "8"6Kr+"2"0"9Bi leading to elements with Z=118-120. The available experimental cross-section data for the reactions are well described.
This report presents a general investigation of the transport requirements associated with the construction and operation of conceptual fusion reactors. Projections of amounts of construction and operating materials requiring transportation are presented for several proposed designs. The material to be shipped is described along with the shipping containers that might be used, the transport modes and the expected impact of transporting these materials. Transportation of both radioactive and nonradioactive materials will be required. Most of these materials are routinely shipped by the transportation industry. Transportation requirements of a representative fusion reactor are also compared with Liquid Metal Fast Breeder Reactor (LMFBR) requirements.
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.
In this paper the diffusion of tritiated water vapor into concrete walls is studied to evaluate tritiated water retention capacity of a fusion reactor concrete building. Using a model of the tritiated water diffusion determined form experimental results, depth profiles of tritiated water in concrete are calculated in the case of being exposed to air containing tritiated water vapor during the normal operational condition of a fusion reactor. A 0.5-m-thick concrete is sufficient for reactor hall walls from a viewpoint of the tritium containment.
Molar enthalpies of sublimation of 1,2,4-, 1,2,3-, and 1,3,5-tri-hydroxy-benzene, were obtained from the temperature dependence of the vapor pressure measured by the transpiration method. The molar enthalpies of fusion and molar heat capacities of these compounds were measured by DSC. The measured data sets of vaporization, sublimation and fusion enthalpies were checked for internal consistency. Strength of the inter- and intra-molecular hydrogen bonding in di- and tri-hydroxy-benzenes have been assessed.
A concept of a traveling wave direct energy converter (TWDEC) is developed for 14.7-MeV fusion protons based on the principle of a backward wave oscillator. Separation of fusion protons from thermal ions is accomplished by using ExB ion drift. Energy conversion rate up to 0.87 is attained by applying three-stage modulation of the proton beam. A one-dimensional particle-circuit code is developed to examine self-excitation of the traveling wave and its stability under loading. Electrostatic wave with a fixed frequency is excited spontaneously, and stability of the wave is ensured under loading. (author).
Four questions are posed: (1) Is knowledge utilization a rhetorical evocation? (2) Is the conjunction of knowledge with utility part of a cultural system of common sense? (3) Is utility a normative or a descriptive concept? and (4) How does the concept of knowledge utilization figure in the specialized discourse of social scientists? This paper analyzes the concept of knowledge utilization from the perspective of philosophy of language and philosophy of science. Knowledge utilization is a rhetorical evocation that implies concepts of action and knowledge. It is supported by two conceptual fusions. The fusion of value and utility draws on common sense, but does not exhaust colloquial understandings about knowledge and action. The conceptual fusion of knowledge and truth is consistent with common sense but disregards scientific criticism. Both conceptual fusions are thus problematic. But empirical ...
This paper proposes a new approach based on missing value pattern discovery for classifying incomplete data. This approach is particularly designed for classification of datasets with a small...Full Text Available
LLNL is developing the nuclear fusion based Laser Inertial Fusion Energy (LIFE) power plant concept. The baseline design uses a depleted uranium (DU) fission fuel blanket with a flowing molten salt coolant (flibe) that also breeds the tritium needed to sustain the fusion energy source. Indirect drive targets, similar to those that will be demonstrated on the National Ignition Facility (NIF), are ignited at 13Hz providing a 500MW fusion source. The DU is in the form of a uranium oxycarbide kernel in modified TRISO-like fuel particles distributed in a carbon matrix forming 2-cm-diameter pebbles. The thermal power is held at 2000MW by continuously varying the 6Li enrichment in the coolants. There are many options to be considered in the engine design including target yield, U-to-C ratio in th...
Microstructure and properties of a Mg AZ31B laser beam weld without filler are studied using electron microscopy, X-ray diffraction and mechanical tests. The microstructure of the weld is characterized by a narrow heat affected zone, columnar grains and precipitate coarsening in the fusion zone. Texture in the fusion zone is significantly different from the texture of the base material. The residual stress distribution observed is similar at the top and the bottom of the weld, maximum tensile residual stress values are observed in the fusion zone. Tensile tests reveal differences in the mechanical behavior of the fusion zone and the parent material, which can be related to the differences of texture and the resulting deformation mechanisms.
One measured fission and fusion cross sections of "4","6He+"2"0"9Bi and "7Li+"2"0"8Pb reactions within the range from the Coulomb barrier up to 200 MeV. The measured functions of fission and fusion for the mentioned reactions are shown to have close values within the excitation energy wide range. One analyzed the excitation functions of fusion and fission for "4He+"2"0"9Bi, "6He+"2"0"9Bi and "7Li+"2"0"8Pb reactions resulting in formation of "2"1"3","2"1"5At compound systems
... coordinates to allow for multisensor fusion, trajectory ... of an image processing toolkit (iPTK ... effectiveness of data-driven registration processing, spatial ...
Sep 18, 2009 ... It is proposed to develop desensitized optimal filtering ... in robust and/or adaptive generalized Kalman and Sigma-Point filters for ...
It is planned to bulk-heat a unit cell of a fusion reactor solid-breeder blanket in a fission reactor to study thermo-mechanical and thermal-hydraulic properties of fusion blankets. This study investigates the neutronic feasibility of using the Power Burst Facility (PBF) for this purpose. Heating rates were calculated for a Li/sub 2/O experiment placed in the PBF test space. The ANISN code and a 56-group coupled neutron-gamma library based on FLUNG and VITAMIN C were used to compute the heating rates. The results show that an average heating rate level of 1-3 W/cc can be produced in PBF with a local power profile that should be typical of a fusion blanket unit cell.
Cells of the mononuclear phagocyte lineage have the capability to adhere to and fuse with each other and to differentiate into osteoclasts and giant cells. To investigate the macrophage adhesion/fusion...Full Text Available
A simple semianalytical calculation is used to study how a star reacts when its central stock of hydrogen is exhausted and before the next fusion reaction based on helium begins.
Fusion device produces high-level neutrons and #gamma#-rays, which would hazard the safety of the public and workers if the doses would be higher than the regulatory limits because of leakage from the bio-shielding and skyshine. It is essential to monitor the radiation doses in the workshop and the enumerative around fusion devices. A radiation monitoring system (RMS) for full (near and far) areas around a nuclear fusion device has been designed and developed, which can achieve the monitoring and controlling of radiation doses in the workshop area by using the Controller Area Network (CAN), in the institution area by using the Bluetooth Ad hoc network based on a new tree topology formation and routing protocol and in a long range environment by using the General Packet Radio Service (GPRS) network. (authors)
Both travelers were members of a nine-person US delegation that participated in an international workshop on accelerator-based 14 MeV neutron sources for fusion materials research hosted by the University of Tokyo. Presentations made at the workshop reviewed the technology developed by the FMIT Project, advances in accelerator technology, and proposed concepts for neutron sources. One traveler then participated in the initial meeting of the IEA Working Group on High Energy, High Flux Neutron Sources in which efforts were begun to evaluate and compare proposed neutron sources; the Fourth FFTF/MOTA Experimenters' Workshop which covered planning and coordination of the US-Japan collaboration using the FFTF reactor to irradiate fusion reactor materials; and held discussions with several JAERI personnel on the US-Japan collaboration on fusion reactor materials.
A top-level costing model is developed and used to project the cost of electricity (COE) (in mills per kilo watt-hour) expected from conceptual fusion power plants. Application is restricted to magnetic fusion energy (MFE) concepts. These costs are estimated parametrically in terms of the mass of the fusion-power-core (FPC) heater, the power required to sustain a reacting deuterium-tritium plasma, the heat transport/transfer system that delivers the fusion power to the balance of plant (BOP), and the BOP needed to convert the fusion heat to electrical power. Although the highly integrated (simplified) cost-estimating relationships (CERs) used to express COE in terms of FPC mass power density (MPD) [in kilowatt(electric) per tonne] and the engineering gain Q{sub E} (inverse of fraction of gross electric power recirculated to the fusion power plant) apply ...
Recent results of experimental and theoretical investigations, carried out in the Institute of plasma Physics of the NSC KIPT, are presented in the report. The main problems of discussion are as follows: plasma confinement and heating in stellarators and electromagnetic traps; powerful quasi-steady-state plasma accelerators (QSPA); experiments relevant for ITER; fusion Plasma theory; methods of high temperature plasma diagnostics; plasma technology. The main prospects on the IPP investigators are discussed also.
This report discusses the following topics: Fusion-fission in light nuclear systems; High-resolution Q-value measurement for the {sup 24}Mg+{sup 24}Mg reaction; Heavy-ion reactions and limits to fusion; and Hybrid MWPC-Bragg curve detector development.
... Targeted fields of research Continuation of ongoing research - Finalising detailed design work on the ITER project; getting JET operational at full power; Improvement of the basic concepts of fusion devices - Fusion plasmas; theoretical studies; technology watch on research into inertial confinement; new experimental concepts and systems; etc.; Long-term technology - Preparations for building a demonstration reactor (development of tritium breeding blankets; prospective ...
Field reversed configuration (FRC) is a prospective high ? magnetic system for high efficiency D- 3He fusion reactor. Self-consistent FRC plasma profiles and static electric field for reactor calculations are discussed in framework of the model including flow equilibrium and collisionless transport equations. The extrapolations to reactor regimes of plasma confinement scaling laws are considered.
This paper describes a maintenance problem in a fusion power plant. The problem is to specify which life limited parts should be replaced when there is an opportunity. The objective is to minimize the cost rate of replacement parts and of maintenance actions while satisfying a power plant availability constraint. The maintenance policy is to look ahead and replace all parts that will reach their life limits within a time called a screen. Longer screens yield greater system availabilities because more parts are replaced prior to their life limits.
AbstractWe describe the fusion of enhanced green fluorescent protein to the C-terminus of the HsdS DNA sequence-specificity subunit of the Type I DNA modification methyltransferase M.EcoKI....Full Text Available
The conceptual system requirements for the control, data, robotics, and project management (CDRM) system for the next generation of fusion experiments are developed by drawing on the success of the Tara control and data system. The requirements are described in terms of an integrated but separable matrix of well-defined interfaces among the various systems and subsystems. The study stresses modularity, performance, cost effectiveness, and exportability.
In a cold fusion method by electrolysis, a hydrogen occluding material mainly comprising vanadium is used as a material for a negative electrode, and lithium isotopes are incorporated in the material by more than 93%. That is, the ratio of lithium 7 ("7Li) isotope is increased to higher than the natural existent ratio, so that tritium ("3H) concentration in the hydrogen occluding material can be increased, to attain energy at high efficiency. (T.M.).
This illustrated booklet describes the fission process; the use of uranium to produce power in nuclear power stations (and a brief explanation of the differences between the principal types of reactor); the formation of plutonium and fission products; radioactive wastes and their management; nuclear fusion and a conceptual fusion reactor; alpha, beta and gamma radiations; radioisotopes and their applications. (U.K.).
The chromosomal region 17q12-q21 contains a gene (BRCA1) conferring susceptibility to early-onset familial breast and ovarian cancer. An 8000-rad radiation-reduced hybrid (RH) panel was constructed to provide a resource for long-range mapping of this region. A large fraction of the hybrids ([approximately]90%) retained detectable human chromosome 17 sequences. The complete panel of 76 hybrids was scored for the presence or absence of 22 markers from this chromosomal region, including 14 cloned genes, seven microsatellite repeats, and one anonymous DNA segment. Statistical analysis of the marker retention data employing multipoint methods provided both comprehensive and framework maps of this chromosomal region, including distance estimates between adjacent markers. The comprehensive RH map includes 17 loci and spans 179 cRays[sub (8000)]. Likelihood ratios of at least 1000:1 support the 10-locus ...
The economic prospects for magnetic fusion energy can be dramatically improved if for the same total power output the fusion neutron first-wall (FW) loading and the system power density can be increased by factors of 3 to 5 and 10 to 30, respectively. A number of compact fusion reactor embodiments have been proposed, all of which would operate with increased FW loadings, would use thin (0.5 to 0.6 m) blankets, and would confine quasi-steady-state plasma with resistive, water-cooled copper or aluminum coils. Increased system power density (5 to 15 MWt/m/sup 3/ versus 0.3 to 0.5 MW/m/sup 3/), considerably reduced physical size of the fusion power core (FPC), and appreciably reduced economic leverage exerted by the FPC and associated physics result. The unique materials requirements anticipated for these compact reactors are outlined against the well documented backdrop provided by similar needs for the ...
Ternary copper(II) complexes [Cu(L1)B](ClO4) (1, 2) and [Cu(L2)B](ClO4) (3, 4), where HL1 and HL2 are tridentate NSO- and ONO-donor Schiff bases and B is a heterocyclic base, viz. dipyrido[3,2-d:2',3'-f]quinoxaline (dpq, 1 and 3) or dipyrido[3,2-a:2',3'-c]phenazine (dppz, 2 and 4), were prepared and their DNA binding and photoinduced DNA cleavage activity studied. Complex 1, structurally characterized by single-crystal X-ray crystallography, shows an axially elongated square-pyramidal (4 + 1) coordination geometry in which the monoanionic L1 binds at the equatorial plane. The NN-donor dpq ligand exhibits an axial-equatorial binding mode. The complexes display good binding propensity to calf thymus DNA, giving a relative order 2 (NSO-dppz) > 4 (ONO-dppz) > 1 (NSO-dpq) > 3 (ONO-dpq). They cleave supercoiled pUC19 DNA to its nicked circular form when treated with 3-mercaptopropionic acid (MPA) by formation of hydroxyl radicals as the cleavage active species under dark reaction ...
TiH{sub 2} and TiD{sub 2} thick targets were bombarded with 100 to 200 keV protons. Evidence for nuclear reactions was obtained by means of a surface barrier particle detector. Proton irradiation of TiD{sub 2} produced the following observations: {alpha} particle emission identified as (p, {alpha}) reactions from {sup 11}B and {sup 7}Li impurities in the target at ppm concentrations; and {approx}3 MeV proton and {approx}1 MeV triton emission from secondary D-D reactions caused by elastic scattering of the primary proton with a target deuteron. A 3.9 MeV {alpha} particle peak measured by others was not observed. (author)
This paper presents a procedure for transferring the CTOD fracture toughness obtained from laboratory specimens to an equivalent CTOD for structural components, taking constraint loss into account. The Weibull stress criterion is applied to correct the CTOD for constraint loss, which leads to an equivalent CTOD ratio, b, defined as b=d/dWP, where d and dWP are CTODs of the standard fracture toughness specimen and the structural component, respectively, at the same level of the Weibull stress. The CTOD ratio b is intended to apply to the fracture assessment of ferritic steel components to stress levels beyond small-scale yielding. Nomographs are given to determine the b-value as a function of the crack type and size in the component, the yield-to-tensile ratio of the material and the Weibul...
The alpha-particle confinement of future D-T experiments at JET can be severely degraded by Global Alfven Eigenmodes (AE). Scenarios for the excitation of Alfven Eigenmodes in usual (e.g. D-D) plasmas are proposed, which provide a MHD diagnostic and allow the study of the transport of super-Alfvenic ions. Active studies with separate control of TAE amplitude and energetic particle destabilization, measuring the plasma response, give more information than passive studies, in particular concerning the damping mechanisms. The TAE excitation can be achieved by means of the saddle coil and the ICRH antenna. The experimental method is introduced together with a theoretical model for RF excitation. (authors). 6 refs., 3 figs.
A means of determination of a ctive hydrogen of hydroxyl, carboxyl, sulfhydryl, amino, amido and sulfonamido groups by chemical ionization mass spectrometry using ammonia and trideuterioammonia as reagent gases is described. The method is based on exchange of active hydrogen for deuterium occurring during the chemical ionization process using trideuterioammonia, with comparison of m/z for ammonium adduct [M + NH1]+ and trideuterioammonium adduct [M--nH + nD + ND4]+, or of protonated molecular ion [M + H]+ and deuteronated molecular ion [M--nH + nD + D]+ yielding the number of active hydrogens. Applications have been made to several classes of biologically important compounds. PMID:427257
Yeast artificial chromosome (YAC) libraries have been difficult to construct with average insert sizes >400 kilobase pairs when DNA is size-fractionated in low-melting-point agarose. By using yeast chromosomes in mock cloning experiments, the authors found that polyamines should be present whenever agarose containing high molecular weight DNA is melted to protect DNA from degradation. By incorporating polyamines during the cloning procedure, they constructed YAC libraries from mouse and human DNA with average insert sizes of 700 and 620 kilobase pairs, respectively. Several genome equivalents of these YAC libraries were replicated onto the surface of many duplicate agar plates using a 40,000 multipin transfer device. High-density filter replicas were screened by hybridization, and 70 mouse YAC clones from 31 loci and 132 human YAC clones from 49 loci were isolated.
Locomotion is a complex behavior affected by many different brain- and spinal cord systems, as well as by variations in the peripheral nervous system. Recently, we found increased gene expression for EphA4, a gene intricately involved in motor neuron development, between high-active parental strain C57BL/6J and the low-active chromosome substitution strain 1 (CSS1). CSS1 mice carry chromosome 1 from A/J mice in a C57BL/6J genetic background, allowing localization of quantitative trait loci (QTL) on chromosome 1. To find out whether differences in motor neuron anatomy, possibly related to the changes in EphA4 expression, are involved in the motor activity differences observed in these strains, motor performance in various behavioral paradigms and anatomical differences in the ventral roots ...
Goosecoid is a homeobox gene first isolated from a Xenopus dorsal lip cDNA library. Homologous genes have been isolated from mouse, zebrafish, and chick. In all species examined, the gene is expressed and plays an important role during the process of gastrulation in early embryonic development. The authors report here the cloning of the human goosecoid (GSC) from a genomic library and the sequence of its encoded protein. The genomic organization and protein sequence of the human gene are highly conserved with respect to those of its Xenopus and mouse counterparts: all three genes consist of three exons, with conserved exon-intron boundaries. The sequence of the homeo-domain is 100% conserved in most vertebrates. Using somatic cell hybrid and chromosomal in situ hybridization, the gene was mapped to chromosome 14q32.1. 30 refs., 3 figs., 2 tabs.
[alpha]-Melanocyte stimulating hormone ([alpha]-MSH), a hormone originally named for its ability to regulate pigmentation of melanocytes, is a 13-amino-acid post-translational product of the pro-opiomelanocortin (POMC) gene. [alpha]-MSH and the other products of POMC processing, which share the core heptapeptide amino acid sequence Met-Glu (Gly)-His-Phe-Arg-Trp-Gly (Asp), the adrenocorticotropic hormone (ACTH), [beta]-MSH, and [gamma]-MSH, are collectively referred to as melanocortins. While best known for their effects on the melanocyte (pigmentation) and adrenal cortical cells (steroidogenesis), melanocortins have been postulated to function in diverse activities, including enhancement of learning and memory, control of the cardiovascular system, analgesia, thermoregulation, immunomodulation, parturition, and neurotrophism. To identify the chromosomal band encoding the human melanocortin-1 receptor gene, 1 [mu]g of an EMBL clone coding region of the human MC1R ...
Fetal nucleated cells within maternal blood represent a potential source of fetal genes obtainable by venipuncture. The authors used monoclonal antibody against the transferrin receptor (TIR) to identify nucleated erythrocytes in the peripheral blood of pregnant women. Candidate fetal cells from 19 pregnancies were isolated by flow sorting at 12 1/2-17 weeks gestation. The DNA in these cells was amplified for a 222-base-pair (bp) sequence present on the short arm of the Y chromosome as proof that the cells were derived from the fetus. The amplified DNA was compared with standardized DNA concentrations. In the case of the female fetus, DNA prepared from samples at 32 weeks of gestation and cord blood at delivery also showed the presence of the Y chromosomal sequence, suggesting Y sequence mosaicism or translocation. In 10/12 cases where the 222-bp band was absent, the fetuses were female. Thus, they were successful in detecting the Y ...
A mutation to tetracycline sensitivity in a resistant strain of Streptococcus pneumoniae was shown by several criteria to be due to a point mutation in the conjugative o(cat-tet) element found in the chromosomes of strains derived from BM6001, a clinical strain resistant to tetracycline and chloramphenicol. Strains carrying the mutation were transformed back to tetracycline resistance with the high efficiency of a point marker by donor deoxyribonucleic acids from its ancestral strain and from nine other clinical isolates of pneumococcus and by deoxyribonucleic acids from Group D Streptococcus faecalis and Group B Streptococcus agalactiae strains that also carry conjugative tet elements in their chromosomes. It was not transformed to resistance by tet plasmid deoxyribonucleic acids from either gram-negative or gram-positive species, except for one that carried transposon TN916, the conjugative tet element present in the ...
Chemical analyses were done on the abnormal hemoglobins of the five (101 x SEC)F_1 offspring of X- irradiated adult SEC mice to determine which hemoglobin genes were expressed in each hemoglobin variant. Three offspring of irradiated SEC males did not express either of the two kinds of #alpha#-chains normally found in all SEC mice. The deficient #alpha#-chain synthesis caused these mice to exhibit an #alpha#-thalassemia similar to human #alpha#-thalassemia. Scanning electron microscopy was used to show that many erythrocytes of mice with #alpha#-thalassemia have bizarre shapes; e.g. many erythrocytes appeared flattened or had thorny projections (acanthocytes). One mutant with a tandem duplication of a segment of chromosome 7 (site of locus determining #beta#-chain structure) produced twice as much SEC as 101 #beta#-chain polypeptides. One mutant that probably arose by non-disjunction of chromosome 7's in its unirradiated 101 mother and loss of ...
The malM locus of Streptococcus pneumoniae was cloned into one of the two PstI sites of the multicopy S. pneumoniae plasmid pMV158. To eliminate chromosomal transformants in the simultaneous selection for tetracycline resistance (coded by pMV158) and maltose utilization, the host cells contained a chromosomal deletion of the mal gene cluster. Two clones were isolated; one with a 3.3 kb insert (pLS70) which behaved like wild type with respect to maltose utilization, and another with a 2.9 kb insert (pLS69) which behaved as though it contained a down promoter mutation. Preliminary mapping of these clones by restriction analysis placed the 0.4kb deletion on a HindIII fragment in the interior of the chromosomal insert. The recombinant plasmids were able to transform over 50% of a recipient population to Mal/sup +/. Enzyme measurements of the clones indicated an overproduction of amylomaltase, constituting up to 10% of the total ...
Stargardt disease (STGD) and fundus flavimaculatus are infrequent autosomal recessive conditions characterized by a juvenile macular dystrophy and variable degrees of peripheral retinal changes. Linkage analysis performed in 47 STGD/fundus flavimaculatus families demonstrated significant linkage to 13 polymorphic DNA markers on chromosome 1p. The maximum combined two-point lod score was 32.7 (maximum recombination fraction [{theta}{sub max}] = .006) with the polymorphic marker D1S188. Our data demonstrate that STGD and fundus flavimaculatus are the same disorder clinically and genetically and provide further evidence for genetic homogeneity of this phenotype. Analysis of recombination on disease chromosomes placed the STGD gene within a 4-cM interval between markers D1S435 and D1S236. A physical map was constructed of a YAC contig flanking STGD, from markers D1S500 to D1S495, and includes the critical interval delineated by historical ...
ABSTRACT. Chlorarachniophytes are enigmatic marine unicellular algae that acquired photosynthesis by secondary endosymbiosis. Chlorarachniophytes are unusual in that the nucleus of the engulfed algal cell (a green alga) persists in a miniaturized form, termed a nucleomorph. The nucleomorph genome of the model chlorarachniophyte, Bigelowiella natans CCMP621, is 373 kilobase pairs (kbp) in size, the smallest nuclear genome characterized to date. The B. natans nucleomorph genome is composed of three chromosomes, each with canonical eukaryotic telomeres and sub telomeric ribosomal DNA (rDNA) operons transcribed away from the chromosome end. Here we present the complete rDNA operon and telomeric region from the nucleomorph genome of Lotharella oceanica CCMP622, a newly characterized chlorarachn...
We report localization of the human cone transducin (GNAT2) gene using fluorescence in situ hybridization on chromosome 1 in band p13. The recent assignment of a gene for Stargardt disease to the same chromosomal region by linkage analysis prompted us to investigate the possible role of GNAT2 in the pathogenesis of this disease. We investigated 66 unrelated patients for mutations in the coding region of the GNAT2 gene using polymerase chain reaction-single strand conformation polymorphism analysis (SSCP) and direct sequencing. No disease-specific mutations were found, indicating that GNAT2 is probably not involved in the pathogenesis of most cases of Stargardt disease. 19 refs., 1 fig., 1 tab.
Background Identifying susceptibility genes for endophenotypes by studying analogous behaviors across species is an important strategy for understanding the pathophysiology underlying psychiatric disorders. This approach provides novel biological pathways plus validated animal models critical for selective drug development. One such endophenotype is avoidance behavior. Methods In the present study, novel automated registration methods for longitudinal behavioral assessment in home cages are used to screen a panel of recently generated mouse chromosome substitution strains that are very powerful in quantitative trait loci (QTL) detection of complex traits. In this way, we identified chromosomes regulating avoidance behavior (increased sheltering preference) independent of motor activity lev...
Background In chordates, retinoid metabolism is an important target of short-chain dehydrogenases/reductases (SDRs). It is not known whether SDRs play a role in retinoid metabolism of protostomes, such as Drosophila melanogaster. Methods Drosophila genome was searched for genes encoding proteins with ?50% identity to human retinol dehydrogenase 12 (RDH12). The corresponding proteins were expressed in Sf9 cells and biochemically characterized. Their phylogenetic relationships were analyzed using PHYLIP software. Results A total of six Drosophila SDR genes were identified. Five of these genes are clustered on chromosome 2 and one is located on chromosome X. The deduced proteins are 300 to 406 amino acids long and are associated with microsomal membranes. They recognize all-trans-retinaldehyd...
Through an unusual differentiation process, human trophoblast progenitors (cytotrophoblasts) give rise to tumor-like cells that invade the uterus. By an unknown mechanism, invasive cytotrophoblasts exhibit permanent cell cycle withdrawal. Here we report molecular cytogenetic data showing that {approx} 20 to 60 percent of these interphase cells had acquired aneusomies involving chromosomes X, Y, o r16. The incidence positively correlated with gestational age and differentiation to an invasive phenotype. Scoring 12 chromosomes in flow-sorted cytotrophoblasts showed that more than 95 percent of the cells were hyperdiploid. Thus, aneuploidy appears to be an important component of normal placentation, perhaps limiting the proliferative and invasive potential of cytotrophoblasts within the uterus.
Obesity is associated with increased susceptibility to dyslipidemia, insulin resistance, and hypertension, a combination of traits that comprise the traditional definition of the metabolic syndrome. Recent evidence suggests that obesity is also associated with the development of nonalcoholic fatty liver disease (NAFLD). Despite the high prevalence of obesity and its related conditions, their etiologies and pathophysiology remains unknown. Both genetic and environmental factors contribute to the development of obesity and NAFLD. Previous genetic analysis of high-fat, diet-induced obesity in C57BL/6J (B6) and A/J male mice using a panel of B6-ChrA/J/NaJ chromosome substitution strains (CSSs) demonstrated that 17 CSSs conferred resistance to high-fat, diet-induced obesity. One of these CSS st...
Rapid and reliable diagnostic methods are needed to control methicillin-resistant Staphylococcus aureus (MRSA) transmission. We studied the BD GeneOhm? MRSA Assay which is based on one specific amplification product at the junction of the right extremity sequence of the staphylococcal cassette chromosome mec (SCCmec) and the chromosomal sequence of orfX of S. aureus. The test was applied on 95 clinical isolates in Finland: 83% were positive. The isolates giving negative results represented several pulsed-field gel electrophoresis (PFGE) types and harboured SCCmec types IV, V, VI or were new types with different combinations of ccr genes.
Genes for chloramphenicol resistance, Cm(r) and tetracycline resistance, Tc(r), which are present as heterologous insertions in the chromosomes of some clinical isolates of Streptococcus pneumoniae (pneumococcus) and derivative strains, were transferred at a low frequency to other pneumococci by a DNase-resistant filter mating process that resembles conjugation. Cotransfer of Cm(r) and Tc(r) was the most common event. Neither the donor strains nor the transconjugants contained detectable plasmids. Transconjugants acted as donors for transformation and for filter mating and had properties similar to those of the parent strain. The presence of the conjugative plasmid pIP501 in the donor did not appear to influence the transfer properties of the Cm(r) or Tc(r) determinants.
The relationship between X chromosome-linked adrenoleukodystrophy and the red/green color pigment gene cluster on Xq28 was investigated in a large kindred. The DNA in a hemizygous male showed altered restriction fragment sizes compatible with at least a deletion extending from the 5[prime] end of the color pigment genes. Segregation analysis using a DNA probe within the color pigment gene cluster showed significant linkage with adrenoleukodystrophy (logarithm of odds score of 3.19 at [theta] = 0.0). These data demonstrate linkage, rather than association, between a unique molecular rearrangement in the color pigment gene cluster and adrenoleukodystrophy. The DNA changes in this region are thus likely to be helpful for determining the location and identity of the responsible gene. 33 refs., 4 figs.
The integrity of a pipeline system is determined by its weakest links which may be the joints. Heat fusion is the most common method for joining gas distribution polyethylene (PE) piping. There are procedural, thermal, and mechanical aspects of making fusion joints. Acceptable procedural aspects, such as heater calibration and cleanliness, can be assured by rigorous training and certification of the operators. Thermal and mechanical aspects consist of specifying joining conditions such as the heater temperature, heating time, and joining pressure. In the absence of procedural errors, the strength of a fusion joint should depend on the pipe material, pipe dimensions, and the thermal and mechanical joining conditions. Socket heat fusion was studied both experimentally and analytically to determine how the strength of the joint varied with the conditions under which it was made. The standard tensile impact ...
The integrity of a pipeline system is determined by its weakest links which may be the joints. Heat fusion is the most common method for joining gas distribution polyethylene (PE) piping. There are procedural, thermal, and mechanical aspects of making fusion joints. Acceptable procedural aspects, such as heater calibration and cleanliness, can be assured by rigorous training and certification of the operators. Thermal and mechanical aspects consist of specifying joining conditions such as the heater temperature, heating time, and joining pressure. In the absence of procedural errors, the strength of a fusion joint should depend on the pipe material, pipe dimensions, and the thermal and mechanical joining conditions. Socket heat fusion was studied both experimentally and analytically to determine how the strength of the joint varied with the conditions under which it was made. The standard tensile impact ...
Tungsten (W) coating on fusion candidate V-4Cr-4Ti (NIFS-HEAT-2) substrate was demonstrated with plasma spray process for the purpose of applying to protection of the plasma facing surface of a fusion blanket. Increase in plasma input power and temperature of the substrate was effective to reduce porosity of the coating, but resulted in hardening of the substrate and degradation of impact property at 77 K. The hardening seemed to be due to contamination with gaseous impurities and deformation by thermal stress during the coating process. Since all the samples showed good ductility at room temperature, further heating seems to be acceptable for the vanadium substrate. The fracture stress of the W coating was estimated from bending tests as at least 313 MPa, which well exceeds the design stress for the vanadium structure in fusion blanket. (author)
Using an expanded nuclear data base, the transmutation of PCA, AMCR33 (a reduced activation austenitic steel), HT-9, Rafer2 (a reduced activation ferritic steel), V-15%Cr-5%Ti alloy, and SiAlON (a ceramic) were calculated for two positions in the Fast Flux Test Facility (FFTF), three positions in the High Flux Isotope Reactor (HFIR), and the first wall position of both the STARFIRE and MARS conceptual fusion reactors. The peripheral test (PTP) position, and to a lesser extent the radial beryllium (RB) position, of HFIR show significant transmutations which are often in the opposite direction to the transmutations in the fusion conceptual designs. The positions in FFTF, as well as the hafnium covered location in the HFIR RB position show relative minor transmutations.
The calculated radioactive waste inventories of the Turkey Point pressurized water fission reactor (PWR) and the Starfire conceptual fusion tokamak are compared as a function of time from initial start-up to 10,000 years after decommissioning. Only material out of reactor at least one year is considered. The total activity in Ci/W(th) of the Starfire tokamak is slightly greater than that of the PWR during the active lifetimes of the two reactors and beyond 1000 years. However, using reduced activation materials in Starfire can result in about 1/2000 as much long-lived radioactivity as in the fission reactor. It is stressed that comparison of wastes on this basis is not straightforward, since the radioisotopes and methods required for their disposal are different for fusion and fission reactors. 2 refs., 1 fig., 2 tabs.
The subscale Varestraint test has been used to determine the relative hot cracking susceptibility of the fusion zone in four commercial heats of alloy 800. Although all four heats were susceptible to cracking, one heat exhibited a significant increase in cracking relative to the other three. Optical metallography revealed that nearly all the cracking was localized along fusion zone grain boundaries. Microprobe analysis of the grain boundaries detected high concentrations of titanium, silicon, and niobium resulting from partitioning during solidification. The fusion zone hot cracking mechanism in alloy 800 involves the complex interaction of titanium, silicon, niobium, and carbon along the solidification boundaries. SEM and Auger analyses of the hot crack fracture surfaces revealed the presence of (Ti, Nb)-rich carbides, suggesting that these particles precipitate from the liquid which solidifies last on the fracture ...
We provide a first-principles, perturbative derivation of the AdS5/CFT4 Y-system that has been proposed to solve the spectrum problem of N=4 SYM. The proof relies on the computation of quantum effects in the fusion of some loop operators, namely the transfer matrices. More precisely we show that the leading quantum corrections in the fusion of transfer matrices induce the correct shifts of the spectral parameter in the T-system. As intermediate steps we study UV divergences in line operators up to first order and compute the fusion of line operators up to second order for the pure spinor string in AdS5xS5. We also argue that the derivation can be easily extended to other integrable models, some of which describe string theory on AdS4, AdS3 and AdS2 spacetimes.
A reference design was used in preparing a mathematical model of a fusion power plant with a tokamak reactor to investigate the extent to which the uncertainty still inherent in the physical reactor parameters affects the power costs. While only limited reductions of the power costs are achieved by improvements of the reference values for the reactor burn time, power density in the torus and load on the first wall, the power costs rise in keeping with the extent to which these parameters fall short of the reference values. As the results obtained in present-day experiments are still well below the reference values, a great deal of effort is still required in the fields of plasma physics and materials research to achieve an economically operating fusion power plant. (orig.).
About 210 abstracts by Ukrainian and foreign authors submitted to the 11-th International Conference on Plasma Physics and Controlled Fusion and 2-nd Alushta International Workshop on the Role of Electric Fields in Plasma Confinement in Stellarators and Tokamaks have been considered by Conference Program Committee members. All the abstracts have been divided into 9 groups: Magnetic confinement systems (stellarators, tokamaks, alternative conceptions); plasma heating and current drive; ITER and fusion reactor aspects; basic plasma physics; space plasma; plasma dynamics and plasma-wall interaction; plasma electronics; low temperature plasma and plasma technologies; plasma diagnostics.
Recent studies have shown Y chromosome microdeletions associated with male infertility. The factors responsible for Y chromosome microdeletions in spermatozoa remain unresolved. However, the environmental pollutants are known to damage DNA in differentiating and maturing germ cells in the male reproductive tract. Therefore, the aim of this study was to investigate the effects of seminal hexachlorocyclohexane (HCH) and its isomers, an environmental pollutant, in 50 fertile and 50 infertile males in relation to semen quality and the incidence of Y chromosome microdeletion in azoospermic factor (AZF) region. As compared to control, an increased HCH level and significantly decreased semen quality were observed in the infertile males. A positive significant association was found between sperm count with alpha-HCH and beta-HCH in the infertile males. A negative significant association was observed between sperm counts with ...
A 7-kb genomic segment containing the coding sequence for the Drosophila melanogaster Formosa variant of salivary gland secretion protein 3 (sgs3) has been inserted into the snw y, bw, st strain of...Full Text Available
Nucleotide pool sanitizing enzymes Dut (dUTPase), RdgB (dITPase), and MutT (8-oxo-dGTPase) of Escherichia coli hydrolyze noncanonical DNA precursors to prevent incorporation of base...Full Text Available
BackgroundThe association between infertility and sperm disomy is well documented. Results vary but most report that men with severely compromised semen parameters have a significantly...Full Text Available
Targeted genome capture combined with next-generation sequencing was used to analyze 2.9 Mb of the DFNB79 interval on chromosome 9q34.3, which includes 108 candidate genes. Genomic...Full Text Available
Protective immunity against infection with Bacillus anthracis is almost entirely based on a response to the protective antigen (PA), the binding moiety for the two other toxin components....Full Text Available
BackgroundAmplification of 3q26 is one of the most frequent genetic alterations in many human malignancies. Recently, we isolated a novel oncogene eIF-5A2 within...Full Text Available
By using a low-resolution macrorestriction map as the foundation (R. Majumder et al., J. Bacteriol. 176:1105–1112, 1996), an ordered cloned DNA map of the 3.2-Mb chromosome of the hypertoxinogenic...Full Text Available
A gene designated BRCA1, implicated in the susceptibility to early-onset familial breast cancer, has recently been localized to chromosome 17q12-q21. To date, the order of DNA markers mapped within this region has been based on genetic linkage analysis. The authors report the use of multicolor fluorescence in situ hybridization to establish a physically based map of five polymorphic DNA markers and 10 cloned genes spanning this region. Three cosmid clones and Alu-PCR-Generated products derived from 12 yeast artificial chromosome clones representing each of these markers were used in two-color mapping experiments to determine an initial proximity of markers relative to each other on metaphase chromosomes. Interphase mapping was then employed to determine the order and orientation of closely spaced loci by direct visualization of fluorescent signals following hybridization of three probes, each detected in a different color. ...
The complete nucleotide sequence of the cap3A gene of Streptococcus pneumoniae, which is directly responsible for the transformation of some unencapsulated, serotype 3 mutants to the encapsulated phenotype,...Full Text Available
BackgroundThe beta-defensin gene cluster (DEFB) at chromosome 8p23.1 is one of the most copy number (CN) variable regions of the human genome. Whereas individual DEFB CNs have been...Full Text Available
The Chediak-Higashi syndrome (CHS) is a severe autosomal recessive condition, features of which are partial oculocutaneous albinism, increased susceptibility to infections, deficient natural killer cell activity, and the presence of large intracytoplasmic granulations in various cell types. Similar genetic disorders have been described in other species, including the beige mouse. On the basis of the hypothesis that the murine chromosome 13 region containing the beige locus was homologous to human chromosome 1, we have mapped the CHS locus to a 5-cM interval in chromosome segment 1q42.1-q42.2. The highest LOD score was obtained with the marker D1S235 (Z{sub max} = 5.38; {theta} = 0). Haplotype analysis enabled us to establish D1S2680 and D1S163, respectively, as the telomeric and the centromeric flanking markers. Multipoint linkage analysis confirms the localization of the CHS locus in this interval. Three YAC clones were ...
Amplification of oncogenes has been found to be an important prognostic factor in behavior of patients' malignancies. In this study we have used new gel electrophoresis techniques to follow the location...Full Text Available
Human Fas/Apo-1 is a cell-surface protein that mediates apoptosis upon ligation with Fas ligand. The gene lies on the long arm of chromosome 10, consists of nine exons, and spans more than 26 kb of...Full Text Available
Full text: DNA rearrangement events leading to chromosomal aberrations are central to ionizing radiation-induced cell death. Although DNA double-strand breaks are probably the lesion that initiates formation of chromosomal aberrations, little is understood about the molecular mechanisms that generate and modulate DNA rearrangement. Examination of the sequences that flank sites of DNA rearrangement may provide information regarding the processes and enzymes involved in rearrangement events. Accordingly, we developed a method using inverse PCR that allows the detection and sequencing of putative radiation-induced DNA rearrangements in defined regions of the human genome. The method can detect single copies of a rearrangement event that has occurred in a particular region of the genome and, therefore, DNA rearrangement detection does not require survival and continued multiplication of the affected cell. Ionizing radiation-induced DNA ...
Nucleotide sequence analysis of the Escherichia coli chromosomal DNA inserted in the plasmid pLC33-5 of the Clarke and Carbon library [Clarke & Carbon (1976) Cell 9, 91-99] revealed the existence...Full Text Available
We report the emergence of Salmonella enterica isolates of serotype Concord (and its monophasic variant 6,7:l,v:-) producing the extended-spectrum β-lactamases (ESBLs) SHV-12...Full Text Available
Two cellular DNA regions representing common domains for proviral DNA integration ( Mlvi -1 and Mlvi -2) have been identified in Moloney murine leukemia virus-induced rat thymic lymphomas. Cellular...Full Text Available
The state of chromatin during the cell cycle was examined using synchronized cultures of CHO hamster cells. Results support Mazia's dynamic chromosome cycle model and indicate that DNA-interactive chemotherapeutic agents elicit different types of kinetic responses in treated cells, suggesting a degree of specificity of interaction between various alkylating and intercalating agents and the genome. Effects of sarkosyl crystals, heparin, and chemotherapeutic agents, neocarzinostatin and adriamycin, on chromation are discussed. (HLW)
The large aggregating proteoglycan aggrecan is a major structural component of the extracellular matrix of articular cartilage. Recent cDNA cloning of the human aggrecan gene (AGC1) reveals a core protein of at least 2316 amino acids characterized by several distinct structural domains. Two globular domains, termed G1 and G2, are present at the amino terminus of the molecule and a third, termed G3, is present at the carboxy terminus. The G1 domain is homologous in structure to the cartilage link protein and accounts for the aggregating potential of aggrecan through its ability to interact with hyaluronic acid. The aggrecan gene is known to consist of 15 exons, with each exon encoding a distinct functional region of the mature protein. However, while the link protein gene is known to reside on chromosome 5 in the human, the location of the aggrecan gene is currently undetermined in any species. The probe (pAGG2) for the aggrecan gene was mapped on ...
A series of translocation break points found in a subset of human acute leukemias have one of the breaks on human chromosome 11q23. This region has recently been cloned and a large gene, ALL-1, with...Full Text Available
Genome-wide association studies (GWAS) have established a variant, rs10993994, on chromosome 10q11 as being associated with prostate cancer risk. Since the variant is located outside of a protein-coding...Full Text Available
Previous karyotypic studies have indicated a possible series of non-random chromosomal events involved in the progression of melanoma. We sought to define a model of melanocyte tumorigenesis by studying allelic deletions of polymorphic simple tandem repeat markers mapping to chromosome 1, 6q, 7, 9p, 10, 11, 17, and 21 in thirty matched pairs of melanoma and constitutional DNAs. The most frequent and earliest deletions were found on 9p (57%) and 10q (32%) and with the exception of one case, no sample has loss of markers on another chromosome without concomitant loss of markers on 9p and/or 10q. Losses on 6q were also a frequent (32%) event that sometimes occurred in primary melanomas, whereas losses of loci on distal 1p (26%) or 11q (26%) occurred only in metastic melanomas. A background rate (0-17%) of allele loss was seen on chromosomes 7, 17, and 21. Homozygous deletions in a panel of 31 melanoma cell ...
Heat fusion is the most common joining method for polyethylene gas distribution piping. Butt fusion was studied with the intent of relating the quality of the joint to the joining conditions. A semi-empirical approach was used. The thermofluid consequences of joining conditions such as heater temperature, heating time and joining parameter were calculated using a computer model. The model was validated by instrumented tests. The strength of the joints was gauged by destructive mechanical testing. Tensile and tensile impact tests were used. Over 150 joints were fabricated using four different polyethylene resins. Most of the data are given in GRI Report No. 88/0276.2 -- Volume 2: Technical Reference on Butt Heat Fusion Joining of Polyethylene Gas Pipes. A parameter, termed the Joining Parameter, was found to characterize the joining conditions. Of the mechanical tests parameters, the impact energy was found to have the best ...
as for direct energy conversion in specialized direct electrical energy conversion plants. Figure 1. An energetic (~163KeV) proton and a 11boron nucleus fuse ...
The purpose of this study is to determine the thermal reliability of stearic acid, palmitic acid, myristic acid and lauric acid as latent heat energy storage materials with respect to various numbers of thermal cycles. The fatty acids, as phase change materials (PCMs), of industrial grade (purity between 90% and 97%) were subjected to accelerated thermal cycle tests. The differential scanning calorimetry (DSC) analysis technique was applied to the PCMs after 0, 120, 560, 850 and 1200 melt/freeze cycles in order to measure the melting temperatures and the latent heats of fusion of the PCMs. The DSC results indicated that the change in melting temperature for the PCMs was in the range of 0.07-7.87 {sup o}C, and the change in latent heat of fusion was -1.0% to -27.7%, except for stearic acid between 560 and 1200 melt/freeze cycles. However, the decrease in the latent heats of fusion for all the PCMs was not regular with ...
The purpose of this study is to determine the thermal reliability of stearic acid, palmitic acid, myristic acid and lauric acid as latent heat energy storage materials with respect to various numbers of thermal cycles. The fatty acids, as phase change materials (PCMs), of industrial grade (purity between 90% and 97%) were subjected to accelerated thermal cycle tests. The differential scanning calorimetry (DSC) analysis technique was applied to the PCMs after 0, 120, 560, 850 and 1200 melt/freeze cycles in order to measure the melting temperatures and the latent heats of fusion of the PCMs. The DSC results indicated that the change in melting temperature for the PCMs was in the range of 0.07-7.87 deg. C, and the change in latent heat of fusion was -1.0% to -27.7%, except for stearic acid between 560 and 1200 melt/freeze cycles. However, the decrease in the latent heats of fusion for all the PCMs was not regular with ...
Study DesignThis is a retrospective study that was done according to clinical and radiological evaluation.PurposeWe analyzed the clinical and radiological...Full Text Available
Heat fusion is the most common joining method for polyethylene gas distribution piping. Butt fusion was studied with the intent of relating the quality of the joint to the joining conditions. A semi-empirical approach was used. The thermofluid consequences of joining conditions such as heater temperature, heating time and joining parameter were calculated using a computer model. The model was validated by instrumented tests. The strength of the joints was gauged by destructive mechanical testing. Tensile and tensile impact tests were used. Over 150 joints were fabricated using four different polyethylene resins. Most of the data are given in GRI Report No. 88/0276.2 -- Volume 2: Technical Reference on Butt Heat Fusion Joining of Polyethylene Gas Pipes. A parameter, termed the Joining Parameter, was found to characterize the joining conditions. Of the mechanical tests parameters, the impact energy was found to have the best ...
BackgroundBaculovirus, which has a width of 40 nm and a length of 250-300 nm, can display functional peptides, receptors and antigens on its surface by their fusion with a baculovirus...Full Text Available
The purpose of this paper was to inform the reader that prolonged upper airway obstruction after posterior cervical spine surgery is a possible complication for patients with metastatic tumor of upper...Full Text Available
Hypoxia, or reduced oxygen, occurs in a variety of clinical and environmental situations. Hypoxic exposure is associated with decreased muscle mass and a concomitant reduction in exercise capacity,...Full Text Available
LLNL is developing the nuclear fusion based Laser Inertial Fusion Energy (LIFE) power plant concept. The baseline design uses a depleted uranium (DU) fission fuel blanket with a flowing molten salt coolant (flibe) that also breeds the tritium needed to sustain the fusion energy source. Indirect drive targets, similar to those that will be demonstrated on the National Ignition Facility (NIF), are ignited at #approx#13 Hz providing a 500 MW fusion source. The DU is in the form of a uranium oxycarbide kernel in modified TRISO-like fuel particles distributed in a carbon matrix forming 2-cm-diameter pebbles. The thermal power is held at 2000 MW by continuously varying the "6Li enrichment in the coolants. There are many options to be considered in the engine design including target yield, U-to-C ratio in the fuel, fission blanket thickness, etc. Here we report results of design variations and compare them in ...
A quantitative energy pathway comparison is made between a modern oil refinery and genetic fusion hydrogen plant supporting hybrid-electric cars powered by gasoline and hydrogen-optimized internal combustion engines, respectively, both meeting President Clinton's goal for advanced car goal of 80 mpg gasoline equivalent. The comparison shows that a fusion electric plant producing hydrogen by water electrolysis at 80% efficiency must have an electric capacity of 10 GWe to support as many hydrogen-powered hybrid cars as one modern 200,000 bbl/day-capacity oil refinery could support in gasoline-powered hybrid cars. A 10 GWe fusion electric plant capital cost is limited to 12.5 B$ to produce electricity at 2.3 cents/kWehr, and hydrogen production by electrolysis at 8 $/GJ, for equal consumer fuel cost per passenger mile as in the oil-gasoline-hybrid pathway.
Progress is reported in fabrication and coating activities being conducted for the weapons program, nuclear test program, nuclear design program, magnetic fusion program, and miscellaneous applications. (DLC)
The formation of mammalian secondary palate requires a series of developmental events such as growth, elevation and fusion. Despite recent advances in the field of palate development, the process...Full Text Available
Through the innovative design of a novel end plug scheme employing octopole MHD stabilization, the authors present the conceptual design of ''MINIMARS'', a small commercial fusion reactor based on the tandem mirror principle. The current baseline for MINIMARS has a net electric output of 600 MWe and they have configured the design for short construction times, factory-built modules, inherently safe blanket systems, and multiplexing in station sizes of #approx =# 600-2400 MWe. They demonstrate that the compact octopole end cell provides a number of advantages over the more conventional quadrupole (yin-yang) end cell encountered in the MARS tandem mirror reactor study, and enables ignition to be achieved with much shorter central cell lengths. Accordingly, being economic in small sizes, MINIMARS provides an attractive alternative to the more conventional larger conceptual fusion reactors encountered to date, and would contribute significantly to ...
We had previously identified a macrophage surface protein whose expression is highly induced, transient, and specific, as it is restricted to actively fusing macrophages in vitro and in vivo. This protein...Full Text Available
To define the import pathway for apoiso-1-cytochrome c in vivo, the coding region for bacterial chloramphenicol acetyltransferase (CAT) or yeast copper metallothionein (CuMT) was fused to the carboxy...Full Text Available
To increase further the accuracy of flow regime and considering the non-stationary characteristics of differential pressure fluctuation signals of gas-liquid two-phase flow, the flow regime identification method based on recurrence quantification analysis (RQA) and multi-sensor data fusion techniques is put forward. First of all, the recurrence quantification analysis method is used to extract the nonlinear feature parameters of the differential pressure fluctuation signals of gas-liquid two-phase flow, and data fusion of feature layer is conducted by QRA feature parameters of differential pressure signals of three pressure measure intervals, and composes the fusion feature vectors. The fused characteristic vector are input into the support vector machine for identify flow regime. The identification results for four typical flow regimes of air-water two-phase flow in horizontal pipe has shown that the reliability of the ...
The subject of FDD (fault detection and diagnosis) has gained widespread industrial interest in machine condition monitoring applications. This is mainly due to the potential advantage to be achieved from reduced maintenance costs, improved productivity and increased machine availability. This paper presents a new FDD scheme for condition machinery of an industrial steam turbine using a data fusion methodology. Fusion of a SVM (support vector machine) classifier with an ANFIS (adaptive neuro-fuzzy inference system) classifier, integrated into a common framework, is utilized to enhance the fault detection and diagnostic tasks. For this purpose, a multi-attribute data is fused into aggregated values of a single attribute by OWA (ordered weighted averaging) operators. The simulation studies indicate that the resulting fusion-based scheme outperforms the individual SVM and ANFIS systems to detect and diagnose incipient steam ...
Fibroblast growth factor (FGF) signaling is involved in skeletal development of the vertebrate. Gain-of-function mutations of FGF receptors (FGFR) cause craniosynostosis, premature fusion of the skull,...Full Text Available
A comprehensive dataset of NDV genome sequences was evaluated using bioinformatics to characterize the evolutionary forces affecting NDV genomes. Despite evidence of recombination in most genes, only one event in the fusion gene of genotype V viruses produced evolutionarily viable progenies. The codon-associated rate of change for the six NDV proteins revealed that the highest rate of change occurred at the fusion protein. All proteins were under strong purifying (negative) selection; the fusion protein displayed the highest number of amino acids under positive selection. Regardless of the phylogenetic grouping or the level of virulence, the cleavage site motif was highly conserved implying that mutations at this site that result in changes of virulence may not be favored. The coding sequence of the fusion gene and the genomes of viruses from wild birds displayed higher yearly rates of change in ...
Porous Nitinol (PNT) has found vast applications in the medical industry as interbody fusion devices, synthetic bone grafts, etc. However, the tendency of the PNT to corrode is anticipated to...Full Text Available
Prof. Kodi Husimi was the director of the Institute of Plasma Physics of Nagoya University during 12 years from the beginning of the institute establishment in 1961. His main contribution on promotion of plasma physics and fusion research at the Institute is summarized. (author)
The longitudinal and transverse dynamics of a heavy ion fusion beam during the drift compression and final focus phase is studied. A lattice design with four time-dependent magnets is described that focuses the entire beam pulse onto a single focal point with the same spot size.
The newly developed techniques by the Hot Laboratory (JMTR HL) have provided for us the key information on behavior of specimens due to mechanical / physical / chemical / synergistic effects of radiation, stress and water for fission and fusion reactor environment. These techniques are focused on several topics as follows; (1) miniaturized specimen test for the development of fusion reactor materials, (2) slow strain rate tensile testing (SSRT) and crack propagation measuring tests for the study of Irradiation Assisted Stress Corrosion Cracking (IASCC) of core internals of LWR, (3) handling technique on specimens including tritium for the research and development of tritium breeders and neutron multiplier as fusion blanket materials, (4) joining method using the Tungsten Inert Gas (TIG) welding technique for re-assembling of capsule and re-fabrication of specimen and (5) nondestructive evaluation using ultrasonic wave and ...
Modern imaging technologies visualize different aspects of disease in a non-invasive way. Considerable progress has been made in the fusion of images from different imaging modalities using software approaches. One goal of fusion software is to align anatomical and functional images and allow improved spatial localization of abnormalities. The resulting correlation of the anatomical and functional images may clarify the nature of the abnormality and help diagnose or stage the underlying disease. Whereas successful image fusion software has been developed for the brain, only limited success has been achieved for image alignment in other parts of the body. The development and current status of alternative approaches are presented. Dual-modality imaging is described with devices where two modalities are combined and mounted in a single gantry. The use of existing scanner technology ensures that no compromises are made in the ...
Using an expanded nuclear data base, the activation of nitrogen, aluminum, iron, nickel, copper, zirconium, niobium, molybdenum, tungsten, and lead were calculated for the first wall positions of the STARFIRE and MARS conceptual fusion reactors.
Mechanical forces can regulate various functions in living cells. The cytoskeleton is a crucial element for the transduction of forces in cell-internal signals and subsequent biological responses. Accordingly,...Full Text Available
T-history method, developed for measuring heat-of-fusion of phase change material (PCM) in sealed tubes, has the advantages of a simple experimental device and convenience with no sampling process. However, some improper assumptions in the original method, such as using a degree of supercooling as the end of latent heat period and neglecting sensible heat during phase change, can cause significant errors in determining the heat of fusion. We have improved this problem in order to predict better results. The present study shows that the modified T-history method is successfully applied to a variety of PCMs such as paraffin and lauric acid having no or a low degree of supercooling. Also it turned out that selected periods for sensible and latent heat do not significantly affect the accuracy of heat- of-fusion. As a result, the method can provide an appropriate means to assess a newly developed PCM by a cycle test even if a ...
A conceptual fusion synfuel production system has been developed with the unique features of: (1) a fusion blanket producing high-temperature (1250"0C) process heat, and (2) the GA sulfur-iodine thermochemical cycle. The system incorporates a two-zone blanket which achieves a tritium breeding ratio of 1.1 while delivering a high fraction (30%) of the fusion heat at high temperatures (1250"0C). The multiple barriers to tritium permeation in the blanket design permit the hydrogen product to meet 10CFR20 regulatory requirements without stringent requirements on the tritium recovery systems. A ceramic heat exchanger, incorporating SiC tubes and headers to contain the process stream and a cooled, Inconel 718 pressure shell to contain the helium, was designed for transferring the heat from the high-temperature coolant to the process. A good heat-line match of the blanket heatsource temperature distribution to the requirements of ...
Concept Exploration (CE) experiments within the Innovative Confinement Concept Program have a unique role which impacts their contributions to the development of fusion energy. As stated in the FESAC ''Report on Alternate Concepts:'' These [CE] programs are aimed at innovation and basic understanding of relevant scientific phenomena. The emphasis on innovation motivates their application to the search for a better fusion reactor configuration. In addition, because of their unique character the CE experiments offer excellent opportunities to couple fusion-plasma physics to other sciences. A recent example of coupling is the fusion self-organized plasmas to reconnection physics and extra-terrestrial plasmas. Perhaps of even greater importance is the education of the future scientists needed for developing fusion energy. The CE experiments, both at ...
High power and particle deposition on target materials are encountered in many applications including magnetic and inertial fusion devices, nuclear and high energy physics applications, and laser and discharge produced plasma devices. Surface and structural damage to plasma-facing components due to the frequent loss of plasma confinement remains a serious problem for the Tokamak reactor concept. The deposited plasma energy causes significant surface erosion, possible structural failure, and frequent plasma contamination.
Open descendants extend conformal field theory to unoriented surfaces with boundaries. The construction rests on two types of generalizations of the fusion algebra. The first is needed even in the relatively simple case of diagonal models. It leads to a new tensor that satisfies the fusion algebra, but whose entries are signed integers. The second is needed when dealing with non-diagonal models, where Cardy's ansatz does not apply. It leads to a new tensor with positive integer entries, that satisfies a set of polynomial equations and encodes the classification of the allowed boundary operators. (orig.).
Heat-of-fusion storage materials for low temperature latent heat storage in the temperature range 0-120 C are reviewed. Organic and inorganic heat storage materials classified as paraffins, fatty acids, inorganic salt hydrates and eutectic compounds are considered. The melting and freezing behavior of the various substances is investigated using the techniques of Thermal Analysis and Differential Scanning Calorimetry. The importance of thermal cycling tests for establishing the long-term stability of the storage materials is discussed. Finally, some data pertaining to the corrosion compatibility of heat-of-fusion substances with conventional materials of construction is presented.
Within the APROS simulation environment we have built a thermo-hydraulic model of a conceptual fusion power plant which is water cooled and uses lithium-lead for tritium breeding. For the safety assessment of this design we have studied an accident sequence which starts from a loss or coolant flow then leads to first wall breach and pressurisation of the vacuum vessel. Simulations have revealed strong pressure transients which can be alleviated by design changes. One goal is to verify the adequacy of the containment design: it remains intact at least 14 h without any mitigating efforts. Estimates for radioactive releases are obtained. (author)
The Joint European Torus (JET) fusion machine is the only device capable of operation with tritium (as fuel) and Be (as plasma facing component), what makes it best suited to study ITER relevant issues. A large variety of activities are performed within the JET Fusion Technology Task Force. In this paper, some topics such as erosion/deposition and material transport, flakes characterization and detritiation techniques are highlighted. Recent results obtained using a pumping cryo-panel and on plasma facing component characterisation are given. Finally, issues that will be addressed in the forthcoming JET work-programme are presented, such as a beryllium main wall for JET and in-situ laser detritiation. (authors)
The fusion excitation function for the radioactive projectile "8 Li on a "2"0"8 Pb target has been measured at energies near the Coulomb barrier. The results show that in the considered energy interval, the evaporation of four neutrons is the most relevant mechanism. However, at the highest energies used in the experiment, the Sn channel begins to appear. The preliminary experimental cross sections show a good agreement with the predictions of a simple evaporation calculation using the code PACE. (Author) 16 refs., 1 tab., 4 figs.
Alpha particle confinement is necessary for ignition of a D-T tokamak fusion plasma and for first wall protection. Due to high radiation backgrounds and temperatures, scintillators and semiconductor detectors may not be used to study alpha particles which are lost to the first wall during the D-T programs on JET and ITER. An alternative method of charged particle spectrometry capable of operation in these harsh environments, is proposed: it consists of thin foils of electrically isolated conductors with the flux of alpha particles determined by the positive current flowing from the foils. 2 refs., 3 figs.
Negative ion based neutral beam injector is one of the most attractive heating system in future fusion reactors. In realizing the system, the crucial device which has to be developed is a high intensity negative ion source. Significant progress has been made on the negative ion source in these years. Among them, a few ampere negative ion beam were produced stably, while the divergence of negative ion beams becomes to be as low as < 10 mrad. We consider these results are demonstrating the potential of the negative ion source for the heating device in future reactors.
Inertial Electrostatic Confinement (IEC) fusion was recently described by an Electric Power Research Institute (EPRI) review panel as potentially leading to a most attractive fusion reactor from a utility point of view, if the physics issues can be resolved. Consequently, a design for a small 25-MW electric D-"3He fueled power plant has been explored. Key power plant components consist of the IEC, direct energy conversion and a step-down converter for electrical power transmission. (author).
One example of basic and applied research at LLNL that has produced major, highly visible scientific and engineering advances has been the research related to controlled fusion energy. Continuing experimentation at LLNL and elsewhere is likely to demonstrate that fusion is a viable, inexhaustible alternative source of energy. Having conducted major fusion energy experiments for over 30 years at LLNL, it scientists and engineers recognized the enormous challenges that lay ahead in this important endeavor. To be successful, it was clear that collaborative efforts with universities, private industry, and other national laboratories would need to be greatly expanded. Along with invention and scientific discovery would come the challenge of transferring the myriad of new technologies from the laboratories to the private sector for commercialization of the fusion energy process and the application of related ...
The most serious challenges in the design of chambers for inertial fusion energy (IFE) are 1) protecting the first wall from fusion energy pulses on the order of several hundred megajoules released in the form of x rays, target debris, and high energy neutrons, and 2) operating the chamber at a pulse repetition rate of 5-10 Hz (i.e., re-establishing, the wall protection and chamber conditions needed for beam propagation to the target between pulses). In meeting these challenges, designers have capitalized on the ability to separate the fusion burn physics from the geometry and environment of the fusion chamber. Most recent conceptual designs use gases or flowing liquids inside the chamber. Thin liquid layers of molten salt or metal and low pressure, high-Z gases can protect the first wall from x rays and target debris, while thick liquid layers have the added benefit of protecting structures from ...
The most striking achievement in magnetic fusion experiments during last few years was the discovery of plasma detachment from material targets, a much needed effect for plasmas with high power fusion parameters. Due to the very low heat loads on the targets observed in these regimes and potentially low erosion of the targets, detached regimes look attractive from the International Thermonuclear Experimental Reactor (ITER) design point of view. Thus the author has experimental proof for the possibility for a co-existence of fusion relevant hot plasma in the core and a low temperature partly ionized plasma at the edge of magnetic fusion device. Although somewhat similar behavior of edge plasma was considered theoretically even before plasma detachment was found experimentally, it was not clear in the beginning how these theoretical and experimental findings would fit together. Now, after a few years of ...
We have constructed a specific supersymmetric flipped SU(5) GUT model in which bilarge neutrino mixing is incorporated. Because the up-type and down-type quarks in the model are flipped in the representations ten and five with respect to the usual SU(5), the radiatively generated flavor mixing in squark mass matrices due to the large neutrino mixing has a pattern different from those in the conventional SU(5) and SO(10) supersymmetric GUTs. This leads to phenomenological consequences quite different from SU(5) or SO(10) supersymmetric GUT models. That is, it has almost no impact on B physics. On the contrary, the model has effects in top and charm physics as well as lepton physics. In particular, it gives promising prediction on the mass difference, #DELTA#M_D, of the D-D-bar mixing which for some ranges of the parameter space with large tan#beta# can be at the order of 10"9 #Planck constant# s"-"1, one order of magnitude smaller than the experimental upper bound. ...
Electronic properties of passive films formed on Fe at various applied potentials in pH 8.5 buffer solution were examined through the photocurrent measurement and impedance spectroscopy. Passive film formed on Fe at relatively low potentials was found to be r-FeOOH layer and internal r-Fe{sub 2}O{sub 3} layer. However, the r-FeOOH layer became unstable and disappeared at potentials below 400mV and hence may be an adsorbed layer. An electronic band structure model for the passive film of Fe was suggested on the basis of the spinel band model with involving two types of electronic excitation processes, i. e., the p-d and the d-d transition together. The effects of applied potential on the photocurrent behaviors of the passive film on Fe were explained appropriately by separating the photocurrent spectra depending on the transition type. The Mott-Schottky behavior for the passive film on Fe and the photocurrent variation with applied potential were also analyzed in ...
In the United States today, governments at all levels and the citizenry are paying increasing attention to the effects, both real and hypothetical, of industrial activity on the environment. Responsible modem industries, reflecting this heightened public and regulatory awareness, are either substituting benign materials for hazardous ones, or using hazardous materials only under carefully controlled conditions. In addition, present-day environmental consciousness dictates that we deal responsibly with legacy wastes. The decontamination and decommissioning (D&D) of facilities at which mercury was used or processed presents a variety of challenges. Elemental mercury is a liquid at room temperature and readily evaporates in air. In large mercury-laden buildings, droplets may evaporate from one area only to recondense in other cooler areas. The rate of evaporation is a function of humidity and temperature; consequently, different parts of a building may be sources ...
Abstract We present the first numerical,-N-body, hydrodynamical, chemical simulations of cosmic structure formation in the framework of non-Gaussian models. We study the impact of primordial non-Gaussianities on early chemistry (e-, H, H+, H-, He, He+, He++, H2, H+2, D, D+, HD, HeH+), molecular and atomic gas cooling, star formation, metal (C, O, Si, Fe, Mg, S) enrichment, Population-III (popIII) and Population-II-I (popII) transition and on the evolution of -visible- objects. We find that non-Gaussianities can have some consequences on baryonic structure formation at very early epochs, but the subsequent evolution at later times washes out any difference among the various models. When assuming reasonable values for primordial non-Gaussian perturbations, it turns out that they are responsi...
We present the latest developments for the radiation laboratory curriculum at the Department of Physics and Astronomy of Western Kentucky University. During the last decade, the Applied Physics Institute (API) at WKU accumulated various equipment for radiation experimentation. This includes various neutron sources (computer controlled d-t and d-d neutron generators, and isotopic 252 Cf and PuBe sources), the set of gamma sources with various intensities, gamma detectors with various energy resolutions (NaI, BGO, GSO, LaBr and HPGe) and the 2.5-MeV Van de Graaff particle accelerator. XRF and XRD apparatuses are also available for students and members at the API. This equipment is currently used in numerous scientific and teaching activities. Members of the API also developed a set of laboratory activities for undergraduate students taking classes from the physics curriculum (Nuclear Physics, Atomic Physics, and Radiation Biophysics). Our goal is to develop a set of ...
This paper describes a reactor design to facilitate a room-temperature nuclear fusion/fission reaction to generate heat without generating unwanted neutrons, gamma rays, tritium, or other radioactive products. The room-temperature fusion/fission reaction involves the sequential triggering of billions of single-molecule, "6LiD 'fusion energy pellets' distributed in lattices of a palladium ion accumulator that also acts as a catalyst to produce the molecules of "6LiD from a solution comprising D_2O, "6LiOD with D_2 gas bubbling through it. The D_2 gas is the source of the negative deuterium ions in the "6LiD molecules. The next step is to trigger a first nuclear fusion/fission reaction of some of the "6LiD molecules, according to the well-known nuclear reaction: "6Li + D #-># 2"4He + 22.4 MeV. The highly energetic alpha particles ("4He nuclei) generated by this nuclear reaction within the palladium ...
This paper introduces the JNM Special Issue on the development of a first wall for the reaction chamber in a laser fusion power plant. In this approach to fusion energy a spherical target is injected into a large chamber and heated to fusion burn by an array of lasers. The target emissions are absorbed by the wall and encapsulating blanket, and the resulting heat converted into electricity. The bulk of the energy deposited in the first wall is in the form of X-rays (1.0-100 keV) and ions (0.1-4 MeV). In order to have a practical power plant, the first wall must be resistant to these emissions and suffer virtually no erosion on each shot. A wall candidate based on tungsten armor bonded to a low activation ferritic steel substrate has been chosen as the initial system to be studied. The choice was based on the vast experience with these materials in a nuclear environment and the ability to address most of the key remaining ...
The loss of #alpha#-globin gene transcriptional activity rarely occurs as an acquired abnormality during the evolution of myeloproliferative disease or preleukemia. To test whether the mutation responsible for the loss of #alpha#-globin gene expression (hemoglobin H disease) in these patients is linked with the #alpha#-globin genes on chromosome 16, the authors transferred chromosome 16 from preleukemic patients with acquired hemoglobin H disease to mouse erythroleukemia cells and measured the transcriptional activity of the human #alpha#-globin genes. After transfer to mouse erythroleukemia cells, the expression of human #alpha#-globin genes from the peripheral blood or marrow cells of preleukemic patients with acquired hemoglobin H disease was similar to that of human #alpha#-globin genes transferred to mouse erythroleukemia cells from normal donors. These data showed that factor(s) in the mouse erythroleukemia cell can genetically complement ...
In experiments designed to detect new mutations affecting hemoglobin, we irradiated the male or female parent in reciprocal crosses of two mouse strains that differ in alleles at the hemoglobin (Hba, Hbb) loci as well as at five other specific loci. Offspring were analyzed for hemoglobin properties (electrophoretic pattern, solubility, crystal pattern), serum albumin differences, erythrocyte lysis, reticulocyte count, and external appearance. Five hemoglobin variants were found among the mutants. In three, the genetic contribution from the irradiated father was not expressed with regard to the #alpha#-chain; one carried a tandem duplication (the first known case in the mouse) involving Hbb; and one probably resulted from double nondisjunction of chromosome 7. The finding that major chromosome aberratios can mimic hemoglobin mutations indicates the need, in similar experiments, to follow F_1 screening with thorough cytogenetic analysis. The ...
Non-Hodgkin lymphoma is a common feature of AIDS. Approximately 30-40% of these tumors exhibit clinical features suggestive of endemic Burkitt lymphoma: they are aggressive malignancies that occur in association with Epstein-Barr virus infection, they arise in the setting of immunosuppression, and they carry t(8;14) translocations without detectable rearrangement of the MYC oncogene. To understand the molecular basis of these parallels, the authors analyzed a case of Epstein-Barr-positive AIDS-associated undifferentiated lymphoma. Southern blots show that the tumor exhibits immunoglobulin joining segment rearrangement but no rearrangement of the MYC oncogene. Cloning of the rearranged joining segment allowed the isolation of recombinant clones encompassing the translocation breakpoint, and sequencing of the translocation junction disclosed that the breakpoint is situated 7 base pairs from the chromosome 14 site involved in a previously described endemic Burkitt ...
Radixin is a cytoskeletal protein that may be important in linking actin to the plasma membrane. Recent cloning of the murine and porcine radixin cDNAs revealed a protein highly homologous to ezrin and moesin. The authors have cloned and sequenced the human radixin cDNA and found the predicted amino acid sequence for the human protein to be nearly identical to those predicted for radixin in the two other species. By Southern analyses of Chinese hamster x human somatic cell hybrid DNA and of PCR products derived from hybrids, the coding gene (RDX) was mapped to 11q. Fluorescence chromosomal in situ hybridization with a cDNA plasmid further localized this gene to band 11q23. However, PCR amplification with [open quotes]radixin-specific[close quotes] primers on the hybrid DNA panel yielded an additional, very similar DNA sequence that was further characterized by direct sequencing of PCR products. This sequence represents a truncated version and the respective locus ...
We have exploited {open_quotes}progeny testing{close_quotes} to map quantitative trait loci (QTL) underlying the genetic variation of milk production in a selected dairy cattle population. A total of 1,518 sires, with progeny tests based on the milking performances of >150,000 daughters jointly, was genotyped for 159 autosomal microsatellites bracketing 1645 centimorgan or approximately two thirds of the bovine genome. Using a maximum likelihood multilocus linkage analysis accounting for variance heterogeneity of the phenotypes, we identified five chromosomes giving very strong evidence (LOD score {ge} 3) for the presence of a QTL controlling milk production: chromosomes 1, 6, 9, 10 and 20. These findings demonstrate that loci with considerable effects on milk production are still segregating in highly selected populations and pave the way toward marker-assisted selection in dairy cattle breeding. 44 refs., 4 figs., 3 tabs.
The chicken extracellular matrix glycoprotein ES/130 is necessary for epithelial-mesenchymal transformation in the developing hear and is also expressed in noncardiac chicken tissues such as limb and notochord. We have identified hES, the human homology of chicken ES/130. Fluorescence in situ hybridization analysis (FISH) localizes hES to human chromosome 20p11.2-p12. FISH analyses of individuals with 20p12 deletions and affected by Alagille syndrome exclude hES as a candidate gene for this disorder. Reverse transcriptase-polymerase chain reaction studies reveal that hES is expressed in both fetal and adult human tissues and that hES expression in the left ventricle is increased in the failing adult heart. Further studies will evaluate how hES mutations may relate to congenital human cardiac and skeletal anomalies as well as cardiac remodeling in the adult. 16 refs., 2 figs.
Tissue factor pathway inhibitor (TFPI), a protease inhibitor that circulates in association with plasma lipoproteins (VLDL, LDL and HDL), helps to regulate the extrinsic blood coagulation cascade. The authors have cloned a 125-kb genomic region containing the entire human TFPI gene on six overlapping cosmids and prepared a restriction map of this contig to clarify gene structure. More than half (45 kb) of the 85-kb gene is occupied with 5[prime] noncoding elements: coding begins at exon 3. A HindIII RFLP identified with one cosmid was genotyped in the CEPH panel of 559 reference families. Linkage analysis using markers on human chromosome 2 located the TFPI gene on 2q, 36 cM proximal to D2S43(pYNZ15) and 13 cM distal to the crystalline [gamma]-polypeptide locus CRYGP1(p5G1). 31 refs., 3 figs., 3 tabs.
The Drosophila hairy gene encodes a basic helix- loop-helix protein that functions in at least two steps during Drosophila development: (1) during embryogenesis, when it partakes in the establishment of segments, and (2) during the larval stage, when it functions negatively in determining the pattern of sensory bristles on the adult fly. In the rat, a structurally homologous gene (RHL) behaves as an immediate-early gene in its response to growth factors and can, like that in Drosophila, suppress neuronal differentiation events. Here, the authors report the genomic cloning of the human hairy gene homolog (HRY). The coding region of the gene is contained within four exons. The predicted amino acid sequence reveals only four amino acid differences between the human and rat genes. Analysis of the DNA sequence 5[prime] to the coding region reveals a putatitve untranslated exon. To increase the value of the HRY gene as a genetic marker and to assess its potential involvement in genetic ...
Biomonitoring of human populations for exposure to genotoxic/clastogenic agents in the environment or the workplace must depend upon statistical tests for elevations in the frequencies of the biological endpoints being monitored, usually chromosomal aberrations (CA), micronuclei (MN), or sister chromatid exchanges (SCE) in peripheral blood lymphocytes. Statistical tests are based, in turn, upon certain assumptions regarding the distribution of the test statistic. When they are often not recognized as such, tests of significance can be in error, and any conclusion drawn that there is or is not a statistically significant difference between one population sample and another maybe erroneous. In population monitoring this means either false negatives or false positives can result and it is hard to know which is worse. Furthermore, even the intelligent design of studies whose object is to test for an elevated level in an exposed population must depend upon prior ...
The classical phenomenon of position-effect variegation (PEV) is the mosaic expression that occurs when a chromosomal rearrangements moves a euchromatic gene near heterochromatin. A striking feature of this phenomenon is that genes far away from the junction with heterochromatin can be affected, as if the heterochromatic state {open_quotes}spreads.{close_quotes} We have investigated classical PEV of a Drosophila brown transgene affected by a heterochromatic junction {approximately} 60 kb away. PEV was enhanced when the transgene was locally duplicated using P transposase. Successive rounds of P transpose mutagenesis and phenotypic selection produced a series of PEV alleles with differences in phenotype that depended on transgene copy number and orientation. As for other examples of classical PEV, nearby heterochromatin was required for gene silencing. Modifications of classical PEV by alterations at a single site are unexpected, and these observations contradict ...
We report the isolation of cDNA clones for the mouse {alpha}7 neuronal nicotinic acetylcholine receptor subunit (gene symbol Acra7), the only nicotinic receptor subunit known to bind a-bungarotoxin in mammalian brain. This gene may have relevance to nicotine sensitivity and to some electrophysiologic findings in schizophrenia. The mouse {alpha}7 subunit gene encodes a protein of 502 amino acids with substantial identity to the rat (99.6%), human (92.8%), and chicken (87.5%) amino acid sequences. The {alpha}7 gene was mapped to mouse chromosome 7 near the p locus with the following gene order from proximal to distal: Myod1-3.5 {+-}1.7 cM-Gas2-0.9 cM {+-} 0.9 cM-D7Mit70-1.8 {+-} 1.2 cM- Acra7-4.4 {+-}1.0 cM-Hras1-ps11/Igf1r/Snrp2a. The human gene was confirmed to map to the homologous region of human chromosome 15q13-q14. 26 refs., 3 figs.
An /alpha//sub 2/-adrenergic receptor subtype has been cloned from a human kidney cDNA library using the gene for the human platelet /alpha//sub 2/-adrenergic receptor as a probe. The deduced amino acid sequence resembles the human platelet /alpha//sub 2/-adrenergic receptor and is consistent with the structure of other members of he family of guanine nucleotide-binding protein-coupled receptors. The cDNA was expressed in a mammalian cell line (COS-7), and the /alpha//sub 2/-adrenergic ligand (/sup 3/H)rauwolscine was bound. Competition curve analysis with a variety of adrenergic ligands suggests that this cDNA clone represents the /alpha//sub 2/B-adrenergic receptor. The gene for this receptor is on human chromosome 4, whereas the gene for the human platelet /alpha//sub 2/-adrenergic receptor (/alpha//sub 2/A) lies on chromosome 10. This ability to express the receptor in mammalian cells, free of other adrenergic receptor subtypes, should help ...
Attention deficit disorder (ADHD) is a complex biobehavioral phenotype which affects up to 8% of the general population and often impairs social, academic, and job performance. Its origins are heterogeneous, but a significant genetic component is suggested by family and twin studies. The murine strain, coloboma, displays a spontaneously hyperactive phenotype that is responsive to dextroamphetamine and has been proposed as a genetic model for ADHD. Coloboma is a semi-dominant mutation that is caused by a hemizygous deletion of the SNAP-25 and other genes on mouse chromosome 2q. To test the possibility that the human homolog of the mouse coloboma gene(s) could be responsible for ADHD, we have carried out linkage studies with polymorphic markers in the region syntenic to coloboma (20p11-p12). Five families in which the pattern of inheritance of ADHD appears to be autosomal dominant were studied. Segregation analysis of the traits studied suggested that the best ...
A statistical method is presented for detecting quantitative trait loci (QTLs), based on the linear model. Unlike methods able to detect a few well separated QTLs and to estimate their effects and positions, this method considers the genome as a whole and enables the detection of chromosomal segments involved in the differences between two homozygous lines, and their backcross, doubled haploid, or F[sub 2] progenies, for a quantitative trait. Genetic markers must be codominant, but missing markers are accepted, provided they are missing independently from the experiment. Asymptotic properties, which are of practical use, are developed. This method does not rely on strong genetic hypotheses, and thus does not permit any precise genetic analysis of the trait under study, but it does assess which regions of the genome are involved, whatever the complexity of the genetic determinism (number, effects and interactions among QTLs). Simultaneous use of several methods, ...
The identification of genes influencing sensitivity to stimulants and opioids is important for determining their mechanism of action and may provide fundamental insights into the genetics of drug abuse. We used a panel of C57BL/6J (B6; recipient)x A/J (donor) chromosome substitution strains (CSSs) to identify quantitative trait loci (QTL) for both open field activity and sensitivity to the locomotor stimulant response to methamphetamine (MA). Mice were injected with saline (days 1 and 2) and MA (day 3; 2 mg/kg i.p.). We analyzed the total distance traveled in the open field for 30 min following each injection. CSS-8, -11 and -16 showed reduced MA-induced locomotor activity relative to B6, whereas CSS-10 and -12 showed increased MA-induced locomotor activity. Further analysis focused on CSS...
ABSTRACT: BACKGROUND: The capacity to maintain internal ion homeostasis amidst changing conditions is particularly important for teleost fishes whose reproductive cycle is dependent upon movement from freshwater to seawater. Although the physiology of seawater osmoregulation in mitochondria-rich cells of fish gill epithelium is well understood, less is known about the underlying causes of inter- and intraspecific variation in salinity tolerance. We used a genome-scan approach in Arctic charr (Salvelinus alpinus) to map quantitative trait loci (QTL) correlated with variation in four salinity tolerance performance traits and six body size traits. Comparative genomics approaches allowed us to infer whether allelic variation at candidate gene loci (e.g., ATP1alpha1b, NKCC1, CFTR, and cldn10e) could have underlain observed variation. RESULTS: Combined parental analyses yielded genome-wide significant QTL on linkage groups 8, 14 and 20 for salinity tolerance performance traits, and 1, 19, 20 ...
Full text: An adaptive response is a decreased biological effect induced by a priming radiation dose given prior to a challenge dose. Adaptive responses contradict the linear-nothreshold model of risk estimation. The pKZ1 mouse chromosomal inversion assay is an extremely sensitive assay for studying the mutagenic effect of low dose radiation. A non-linear dose response for chromosomal inversion has been observed in pKZ1 spleen and prostate after a single whole body irradiation with doses between 1?Gy and 10mGy. Doses between 5-10?Gy resulted in an induction in inversions and doses between 1-10mGy resulted in a reduction below endogenous inversion frequency. These results suggest that doses in the 1-10 mGy range cause host responses which overcompensate by not only preventing inversions that would normally occur as a result of the low doses of radiation but also by preventing some of the endogenous inversions that would have occurred in the ...
In order to identify cells of maternal origin in CVS cultures, tissue from 1st trimester abortions were cultivated and the cultures stained in situ for X-chromatin. Convoluted cells and maternal fibroblasts were found to be positive. By chromosome analysis of cultures from 105 diagnostic placenta biopsies, obtained by the transabdominal route, metaphases of maternal origin were found in nine cases. In eight of these cases colonies of convoluted cells were observed. We conclude that convoluted cells are of maternal origin and are a reliable marker for maternal cell contamination in CVS cultures.
This paper considers location?allocation problem in the real uncertain world and develops a possibilistic non-linear programming model to deal with this problem. Fuzzy decision making in fuzzy environment concept is used to determine possibility distribution of location and allocation variables. To solve this model, a novel approach based on genetic algorithm structure is developed. As the proposed model includes both deterministic (location) and uncertain (allocation) parameters, the developed solution algorithm uses a hybrid chromosome structure. Also, to cover continuous nature of the problem and prevent GA from early convergence, a new crossover operator is introduced. Finally, performance of the developed algorithm is evaluated by an example.
We report the case of a 22-year-old man with Ewing's sarcoma who attained a complete remission (CR) after combination radiotherapy and chemotherapy. Secondary acute lymphoblastic leukemia with multiple cytogenetic abnormalities involving chromosome 5 and 7 developed 16 years later. The patient underwent induction chemotherapy and entered a CR. Peripheral blood stem cell transplantation from a matched sibling was performed successfully and he is in complete remission of both ALL and Ewing's sarcoma. (Copyright (c) 1999 Elsevier Science B.V., Amsterdam. All rights reserved.)
Jittery (ji) is a recessive mouse mutation on Chromosome 10 characterized by progressive ataxic gait, dystonic movements, spontaneus seizures, and death by dehydration/starvation before fertility. Recently, a viable neurological recessive mutation, hesitant, was discovered. It is characterized by hesitant, uncoordinated movements, exaggerated stepping of the hind limbs, and reduced fertility in males. In a complementation test and by genetic mapping we have shown here that hesitant and jittery are allelic. Using several large intersubspecific backcrosses and intercrosses we have genetically mapped ji near the marker Amh and microsatellite markers D10Mit7, D10Mit21, and D10Mit23. The linked region of mouse Chromosome 10 is homologous to human 19p13.3, to which several human ataxia loci have recently been mapped. By excluding genes that map to human 21q22.3 (Pfkl) and 12q23 (Nfyb), we conclude that jittery is not likely to be a genetic mouse ...
The centromere is the most characteristic landmark of eukaryotic chromosomes. Centromeres function as the site for kinetochore assembly and spindle attachment, allowing for the faithful pairing and segregation of sister chromatids during cell division. Characterization of centromeric DNA is not only essential to understand the structure and organization of plant genomes, but it is also a critical step in the development of plant artificial chromosomes. The centromeres of most model eukaryotic species, consist predominantly of long arrays of satellite DNA. Determining the precise DNA boundary of a centromere has proven to be a difficult task in multicellular eukaryotes. We have successfully cloned and sequenced the centromere of rice chromosome 8 (Cen8), representing the first fully sequenced centromere from any multicellular eukaryotes. The functional core of Cen8 spans ~800 kb of DNA, which was determined by chromatin ...
Stargardt`s disease (MIM 248200), originally described in 1909, is an autosomal recessive condition of childhood, characterized by a sudden and bilateral loss of central vision. Typically, it has an early onset (7 to 12 years), a rapidly progressive course and a poor final outcome. The central area of the retina (macula) displays pigmentary changes in a ring form with depigmentation and atrophy of the retinal pigmentary epithelium (RPE). Perimacular yellowish spots, termed fundus flavimaculatus, are observed in a high percentage of patients. We have recently reported the genetic mapping of Stargardt`s disease to chromosome 1p13. On the other hand, considering that fundus flavimaculatus (MIM 230100) is another form of fleck fundus disease, with a Stargardt-like retinal aspect but with a late-onset and a more progressive course, we decided to test the hypothesis of allelism between typical Stargardt`s disease and late-onset autosomal recessive fundus flavimaculatus. ...
A rat thyrotropin (thyroid-stimulating hormone, TSH) receptor cDNA was isolated that encoded a protein of 764 amino acids, M_r 86,528. Transfection of the cDNA caused COS-7 cells to develop a TSH-sensitive adenylate cyclase response and the ability to bind "1"2"5I-labeled TSH; both activities were similar to those of rat FRTL-5 thyroid cells and not duplicated by lutropin. The gene represented by the cDNA was assigned to mouse chromosome 12 and human chromosome 14. Northern analyses identified two species of mRNA, 5.6 and 3.3 kilobases, in FRTL-5 thyroid cells; the transcripts appeared to differ only in the extent of their 3' noncoding sequences. There were minimal amounts of the two mRNAs in rat ovary, and neither was detected in RNA preparations from rat testis, liver, lung, brain, spleen, and FRT thyroid cells, which do not have a functional TSH receptor. TSH decreased both mRNA species 3- to 4-fold within 8 hr in FRTL-5 thyroid cells; ...
Proton and alpha particle spectral shapes and multiplicities have been measured in coincidence with evaporation residues from {sup 28}Si+{sup 165}Ho and {sup 16}O + {sup 197}Au, {sup 208}Pb fusion reactions. Our experiments used 145 to 220 MeV {sup 28}Si and 115 and 140 MeV {sup 16}O beams produced with the Stony Brook LINAC. ER`s were separated using an electrostatic deflector and detected with large area surface barrier detectors. Light charged particles were detected at forward and backward angles with fourteen single NaI detectors. In the context of the statistical model, charged particle spectra yield information about emission barriers and compound nucleus equilibrium level densities. These are significant ingredients in calculations determining fission timescales from other observables such as pre-scission neutron multiplicities or fusion-evaporation excitation functions. Results will also be compared to analyses of pre-scission charged ...
An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on conventional design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require unconventional shapes or heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, ...
An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on conventional design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require unconventional shapes or heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, ...
An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on conventional design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require unconventional shapes or heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, ...
Lithium isotopes are used as the raw material of tritium which is the fuel for fusion power generation and the material for fusion reactors, accordingly those are indispensable for future nuclear fusion power generation. As for boron isotopes, the neutron absorption corss section is very large, therefore, they are used for shielding neutrons and controlling fast neutron reactors. In order to further develop the utilization of nuclear power, it is important to develop the technology for separating and refining light element isotopes in large amount. In fiscal year 1995, the relation of the ion sieve characteristics of inorganic ion exchanger and the behavior of lithium isotope separation was examined. The behavior of forming boron complex of polyol amine was examined by B-11 NMR. These experiments and the results are reported. It was shown to be feasible that lithium is adsorbed from seawater, and isotopes are concentrated. ...
The world fusion program has advanced to the stage where it is appropriate to construct a number of devices for the purpose of burning DT fuel. In these next-generation experiments, the expected flux and fluence of 14 MeV neutrons and associated gamma rays will pose a significant challenge to the operation and diagnostics of the fusion device. Radiation effects include structural damage to materials such as vacuum windows and seals, modifications to electrical properties such as electrical conductivity and dielectric strength and impaired optical properties such as reduced transparency and luminescence of windows and fiber optics during irradiation. In preparation for construction and operation of these new facilities, the fusion diagnostics community needs to work with materials scientists to develop a better understanding of radiation effects, and to undertake a testing program aimed at developing workable solutions for ...
In this study, dissimilar welds between HP heat-resistant steel and Incoloy 800 were made with four different filler materials including: 309 stainless steel and nickel-based Inconel 82, 182 and 617. The microstructure of the base metals, weld metals and their interfaces were characterized by utilizing optical and scanning electron microscopy. Grain boundaries migration in the weld metals was studied. It was found that the migration of grain boundaries in the Inconel 82 weld metal was very extensive. Precipitates of TiC and M_2_3C_6 (M = Cr and Mo) in the Inconel 617 weld metal are identified. The necessary conditions for the formation of cracks close to the fusion line of the 309-HP joints are described. Furthermore unmixed zone near the fusion line between HP steel base metal and Inconel 82 weld metal is discussed. An epitaxial growth is characterized at the fusion line of the 309-Alloy 800 and Inconel 617-Alloy 800 ...
The video documents the results of a Small Business Innovative Research (SBIR-Phase II) project conducted for DARPA focusing on the use of all-source overhead remote sensor imagery for monitoring underground nuclear tests and related activities. The documentation includes: (1) the main unclassified body of the report; (2) a separate ground truth Annex; and (3) a separate classified Annex. Autometric's approach was to investigate the exploitation potential of the various sensors, especially the fusion of products from them in combination with each other and other available collateral data. This approach featured empirical analyses of multisensor/multispectral imagery and collateral data collected before, during, and after an actual underground nuclear test (named 'BEXAR'). Advanced softcopy digital image processing and hardcopy image interpretation techniques were investigated for the research. These included multispectral (Landsat, SPOT), ...
The feasibility of developing a fusion power monitor based on a fluid activation detector is considered here. The activation fluid may be either a liquid or a gas and its composition can be selected from a number of candidate materials to provide desired activation and decay characterisitcs. Performance calculations indicate that ordinary water would be a nearly ideal activation fluid. The "1"6O(n,p)"1"6N reaction has a threshold at about 10 MeV and a cross section energy dependence giving it a predominant response for unmoderated D-T fusion neutrons. Adequate activation can be obtained at moderate flow rates for remote counting away from the high radiation area of the reactor. The 7.16 sec half-life of "1"6N is ideal for remote counting with subsequent decay in a small hold-up tank to eliminate activity build-up in the recycled water.
The author have prepared a new, fusion-oriented library of multigroup neutron cross sections, scattering matrices, and covariances (uncertainties and correlations). The 74-group library, called COVFILS-2, has been used, or will be used, by neutronics groups at Los Alamos National Lab. (LANL) at the University of California at Los Angeles, and at the Swiss Federal Institute for Reactor Research in the sensitivity and uncertainty analysis of fusion-relevant integral experiments such as the Li/sub 2/O experiment performed at the Fast Neutron Source Facility in Japan and the Lithium breeding module experiment planned at the LOTUS facility in Lausanne, Switzerland. Another intended use of this library is in the estimation of the uncertainty in key performance parameters (such as the breeding ratio) of conceptual fusion reactors. The 14 materials included in the first version of COVFILS-2 are hydrogen, /sup 6/Li, /sup 7/Li, ...
The author have prepared a new, fusion-oriented library of multigroup neutron cross sections, scattering matrices, and covariances (uncertainties and correlations). The 74-group library, called COVFILS-2, has been used, or will be used, by neutronics groups at Los Alamos National Lab. (LANL) at the University of California at Los Angeles, and at the Swiss Federal Institute for Reactor Research in the sensitivity and uncertainty analysis of fusion-relevant integral experiments such as the Li_2O experiment performed at the Fast Neutron Source Facility in Japan and the Lithium breeding module experiment planned at the LOTUS facility in Lausanne, Switzerland. Another intended use of this library is in the estimation of the uncertainty in key performance parameters (such as the breeding ratio) of conceptual fusion reactors. The 14 materials included in the first version of COVFILS-2 are hydrogen, "6Li, "7Li, beryllium, carbon, ...
Recent experiments with TFTR, D-III-D and JET involving the injection and trapping of low density beams of high energy large orbit ions indicate that large orbit non-adiabatic ions slow down and diffuse classically in the presence of anomalous fluctuations and transport of adiabatic majority particles. Accordingly, we consider conceptual fusion reactors(N. Rostoker, M.W. Binderbauer and H.J. Monkhorst, Science) 278, 1419 (1997). based on classical confinement of fuel ions and fusion products(M.W. Binderbauer and N. Rostoker, J. Plasma Phys.) 56, 451 (1996).. The magnetic confinement geometry of the proposed designs is a Field Reversed Configuration. A survey of experimental results on instabilities and their characteristics as related to these reactor concepts is presented. Particular focus will be given to long wavelength (as compared to gyro-radius) and low frequency (?<< c/r_o, r_o=3D major radius of annular current ring) instabilities ...
The general development of variational methods for fusion reactor blanket studies is given. Important quantities such as tritium breeding ratio and total nuclear heating are linear functionals of the solutions to the Boltzmann transport equation. To estimate a neutronic quantity by variational methods is, in general, to carry out the scalar product formulation of the Roussopoulos variational principle, or the Schwinger variational principle, with the help of the associated adjoint transport equation where the appropriate response function for the estimate is taken as the source. A multipoint interpolation method based on the above variational principles has been developed and compared to other variational approaches. The method of variational interpolation removes the need to compute both forward and adjoint solutions while the error has the characteristic of cancellation of errors between interpolation reference points. Finally, the practical computational ...
The inner part of a fusion reactor will have to operate at very high neutron loads. In steady-state reactors the minimum fluence before the scheduled replacement of the reactor core should be at least l0-15 Mw.yr/m2. A more frequent replacement of the core is hardly compatible with economic constraints. A most recent summary of the discussions of these issues is presented in Ref. [l]. If and when times come to build a commercial fusion reactor, the availability of information on the behavior of materials and components at such fluences will become mandatory for making a final decision. This makes it necessary an early development and construction of a neutron source for fusion material and component testing. In this paper, we present information on one very attractive concept of such a source: a source based on a so called Gas Dynamic Trap. This neutron source was proposed in the mid 1980s (Ref. [2]; ...
Installation of the major hardware subsystems for MFTF is nearing completion. These subsystems include the Fusion Chamber System, the eighty KV Neutral Beam System, the Superconducting Magnet System, and the Personnel Safety System. The Local Controls group has undertaken a uniform aproach to implementing the control systems for all of these hardware subsystems. This approach has two major aspects: (1) to provide a stand-alone computer control system with a remote, portable terminal so that computer control can be provided at the site of the hardware for initial testing, (2) to provide hardware simulators so that the complicated MFTF computer control system can be tested independent of the hardware. The software and hardware tools which were developed to carry out this plan will be described. Our experiences with bringing up subsystems containing up to 900 separate channels of control and status will also be described.
The rationale for hybrid fusion-fission reactors is the production of fissile fuel for fission reactors. A new class of reactor, the fission-suppressed hybrid promises unusually good safety features as well as the ability to support 25 light-water reactors of the same nuclear power rating, or even more high-conversion-ratio reactors such as the heavy-water type. One 4000-MW nuclear hybrid can produce 7200 kg of /sup 233/U per year. To obtain good economics, injector efficiency times plasma gain (eta/sub i/Q) should be greater than 2, the wall load should be greater than 1 MW m/sup -2/, and the hybrid should cost less than 6 times the cost of a light-water reactor. Introduction rates for the fission-suppressed hybrid are unusually rapid.
A fusion reactor (such as NET/ITER) which breeds its own tritium fuel requires tritium recovery, purification and separation from the other isotopes. Cyclic adsorption processes are strong candidates for several of the processes involved: amongst other advantages, they promise a low tritium inventory. A good adsorbent for such processes must have high adsorption capacity, high selectivity and very low tritium retention after each cycle. Pure zeolite powder is shown to have an excellent combination of these three properties. However, in practice problems can arise from tritium which is not removed by reactivation. In this paper we show that tritium retention in zeolites can be caused either by water retained in the zeolite structure, which can be removed by ore rigorous activation, or by water tapped on binders in commercial pellets. (orig.).
A new process engineering flowsheet reflecting an improved design of the LASL Bismuth Sulfate thermochemical cycle is presented. The design is based on laboratory data that indicate a lowered endothermic heat load for a partial decomposition of the solid bismuth sulfate. A small electrical energy demand should result from operation of the sulfur dioxide electrolytic step at lower acid concentration, in principle. The results of the flowsheeting analysis yield a thermal efficiency of 50% for the cycle when coupled to a conceptual fusion energy heat source at 1500/sup 0/K. A parametric analysis shows a slight drop in efficiency as the temperature of the heat source is decreased. The LASL Bismuth Sulfate thermochemical cycle appears to have potential as a means of producing hydrogen from high-temperature heat sources such as fusion, fission, and solar energy; it also appears to be competitive with alternative thermochemical cycles as well as with ...
Solid state lasers, particularly neodymium glass systems, have undergone intensive development during the last decade. In this paper, we review solid state laser technology in the context of high-peak-power systems for inertial confinement fusion. Specifically addressed are five major factors: efficiency, wavelength flexibility, average power, system complexity, and cost; these factors today limit broader application of the technology. We conclude that each of these factors can be greatly improved within current fundamental physical limits. We further conclude that the systematic development of new solid state laser madia, both vitreous and crystalline, should ultimately permit the development of wavelength-flexible, very high average power systems with overall efficiencies in the range of 10 to 20%.
The prospects for the low-aspect-ratio (A) tokamak to fulfill the requirements of viable fusion power plants are considered relative to the present status in data and modeling. Desirable physics and design features for an attractive Blanket Test Facility and power reactors are estimated for low-A tokamaks based on calculations improved with the latest data from small pioneering experiments. While these experiments have confirmed some of the recent predictions for low-A, they also identify the remaining issues that require verification before reliable projections can be made for these deuterium-tritium applications. The results show that the low-A regime of small size, modest field, and high current offers a path complementary to the standard and high A tokamaks in developing the full potential of fusion power.
The irradiation behavior of Li{sub 2}TiO{sub 3} under a fusion reactor environment was simulated by simultaneous irradiation of Li{sub 2}TiO{sub 3} by the triple ion beams and the respective single ion beams of O{sup 2+}, He{sup +} and H{sup +}. The microstructural changes in Li{sub 2}TiO{sub 3} caused by the irradiation were measured by Raman spectroscopy and FT-IR photoacoustic spectroscopy. The results suggest that the formation of TiO{sub 2} due to displacements by irradiation occurs, and the irradiation defects generated by irradiation trap hydrogen and increase the amount of hydroxyl near the surface. Such phenomena are believed to significantly affect the chemical form of the released tritium and the tritium inventory in the breeding materials of a fusion reactor.
The irradiation behavior of Li_2TiO_3 under a fusion reactor environment was simulated by simultaneous irradiation of Li_2TiO_3 by the triple ion beams and the respective single ion beams of O"2"+, He"+ and H"+. The microstructural changes in Li_2TiO_3 caused by the irradiation were measured by Raman spectroscopy and FT-IR photoacoustic spectroscopy. The results suggest that the formation of TiO_2 due to displacements by irradiation occurs, and the irradiation defects generated by irradiation trap hydrogen and increase the amount of hydroxyl near the surface. Such phenomena are believed to significantly affect the chemical form of the released tritium and the tritium inventory in the breeding materials of a fusion reactor.
An FEL based energy driver for Inertial Confinement Fusion (ICF) is proposed. The key element of the scheme is free electron laser system. Novel technical solutions, namely, using of multichannel, multi-stage FEL amplifier with diaphragm focusing line, reveal a possibility to construct the FEL system operating at radiation wavelength {lambda} = 0.5 {mu}m and providing flush energy E = 1 MJ and brightness 4 x 10{sup 22} W cm{sup -2} sr{sup -1} within steering pulse duration {tau} {approximately} 0.1-2 ns. Total energy efficiency of the proposed ICF energy driver is about of 11% and repetition rate is 40 Hz. It is shown that the FEL based ICF energy driver may be constructed at the present level of accelerator technique R& D.
The interaction between a lower hybrid wave and a fusion alpha particle displaces the alpha particle simultaneously in space and energy. This results in coupled diffusion. Diffusion of alphas down the density gradient could lead to their transferring energy to the wave. This could, in turn, put energy into current drive. Here we calculate numerical solutions for the alpha energy transfer and study a range of conditions that are favourable for wave amplification from alpha energy. We find that it is possible for fusion alpha particles to transfer a large fraction of their energy to the lower hybrid wave. The numerical calculation shows that the net energy transfer is not sensitive to the value of the diffusion coefficient over a wide range of practical values. An extension of this idea, the use of a lossy boundary to enhance the energy transfer, is investigated. This technique is shown to offer a large potential benefit. (Author).
The interaction between a lower hybrid wave and a fusion alpha particle displaces the alpha particle simultaneously in space and energy. This results in coupled diffusion. Diffusion of alphas down the density gradient could lead to their transferring energy to the wave. This could, in turn, put energy into current drive. Here we calculate numerical solutions for the alpha energy transfer and study a range of conditions that are favourable for wave amplification from alpha energy. We find that it is possible for fusion alpha particles to transfer a large fraction of their energy to the lower hybrid wave. The numerical calculation shows that the net energy transfer is not sensitive to the value of the diffusion coefficient over a wide range of practical values. An extension of this idea, the use of a lossy boundary to enhance the energy transfer, is investigated. This technique is shown to offer a large potential benefit. (Author).
The interaction between a lower hybrid wave and a fusion alpha particle displaces the alpha particle simultaneously in space and energy. This results in coupled diffusion. Diffusion of alphas down the density gradient could lead to their transferring energy to the wave. This could, in turn, put energy into current drive. An initial analytic study was done by Fisch and Rax. Here the authors calculate numerical solutions for the alpha energy transfer and study a range of conditions that are favorable for wave amplification from alpha energy. They find that it is possible for fusion alpha particles to transfer a large fraction of their energy to the lower hybrid wave. The numerical calculation shows that the net energy transfer is not sensitive to the value of the diffusion coefficient over a wide range of practical values. An extension of this idea, the use of a lossy boundary to enhance the energy transfer, is investigated. This technique is ...
This paper reviews different helium-cooled first wall and blanket designs; and compares the selection of structural materials. The authors found that the solid breeder, SiC-composite material option generates the lowest amount of induced radioactivity and afterheat and has the highest temperature capability. When combined with the direct cycle gas turbine system, it has the potential to be the most economical fusion system and can compete with advanced fission reactors. When compared to martensitic steel and V-alloy, SiC-composite is the least developed of these three structural materials, a focused development effort will be needed. Fundamental research has begun in addressing the issues of optimized composite materials, irradiation effects, leak tightness and low activation braze materials. Development of helium-cooled high heat flux components and further development of the direct cycle gas turbine system will also be needed.
Brookhaven National Laboratory is involved in a conceptual design study of a commercial nuclear power system which utilizes high-temperature electrolysis to produce synthetic fuels. The system is called HYFIRE. It includes a tokamak fusion power reactor supplying electrical and thermal energy to an array of electrolytes. The electrolytes produce hydrogen which can be used either directly as a fuel or in the production of hydrocarbons. The purpose of the study is to provide a mechanism for DOE to further assess the commercial potential of fusion using a tokamak reactor to produce synthetic fuel. The HYFIRE design is based on the tokamak commercial power reactor, STARFIRE. STARFIRE uses the deuterium/tritium/lithium fuel cycle. The HYFIRE study assumes the plasma shape and characteristics of STARFIRE study but uses a different blanket design. This study is particularly interested in the possibility of using the STARFIRE tokamak in the production ...
The antisymmetric many-body trial state which describes a system of interacting fermions is parametrized in terms of localized wave packets. The equations of motion are derived from the time-dependent quantum variational principle. The resulting fermionic molecular dynamics (FMD) equations include a wide range of semi-quantal to classical physics extending from deformed Hartree-Fock theory to newtonian molecular dynamics. Conservation laws are discussed in connection with the choice of the trial state. The model is applied to heavy-ion collisions with which its basic features are illustrated. The results show a great variety of phenomena including deeply inelastic collisions, fusion, incomplete fusion, fragmentation, neck emission, promptly emitted nucleons and evaporation. ((orig.)).
Possible accident scenarios for a fusion reactor include breaches in the vacuum or cooling system. Intruding air or steam could react with structural or plasma facing materials, possibly mobilizing radioactive isotopes. Safety assessments must consider the early dose at the site boundary from the release of these activated materials. Previous calculations have indicated that cobalt isotopes dominate dose calculations for designs using stainless steel. Values used in these calculations, however, had been largely determined by the measurement limits of the chemical analysis methodology instead of measured releases. The purpose of the current study was to refine the analytical method to reduce the limit for detecting cobalt, and then test PCA steel in air and steam between 973 and 1473 K. Goals were to obtain more accurate measurements of cobalt mobilization in terms of g/m{sup 2}{center_dot}h and insight into the mobilization mechanisms.
As a contribution to the US/Japan cooperative program in fusion neutronics, we have prepared a library of multigroup neutron cross sections, scattering matrices, and covariances (uncertainties and their correlations). This 74-group library, called COVFILS-2, is being used at Los Alamos and at the University of California at Los Angeles in the sensitivity and uncertainty analysis of the Li_2O integral experiment recently performed at the Fast Neutron Source (FNS) in Japan. Another intended use of this library is in the estimation of the uncertainty in key performance parameters (such as breeding ratio) of conceptual fusion reactors. The 14 materials included in the first version of COVFILS-2 are H, "6Li, "7Li, Be, C, N, O, Na, Al, Si, Cr, Fe, Ni, and Pb.
We have studied actinide burn-up in ICF reactor pellets; i.e., 14 MeV neutron fission of the very long-lived actinides that pose storage problems. A major advantage of pellet fuel region burn-up is safety: only milligrams of highly toxic and active material need to be present in the fusion chamber, whereas blanket burn-up requires the continued presence of tons of actinides in a small volume. The actinide data tables required for Monte Carlo calculations of the burn-up of /sup 241/Am and /sup 243/Am are discussed in connection with a study of the sensitivity to cross section uncertainties. More accurate and complete cross sections are required for realistic quantitative calculations.
During FY1997, the JMTR was operated for 3 complete cycles (120th, 121st and 122nd cycles) and was utilized for the research and development programs on the technology of LWRs and fusion reactor, as well as for fundamental research of fuels and materials, and for radioisotope productions. The improvement of evaluation technique in a local neutron spectrum for irradiation utilization and development of capsule having the vertical migration, the reinstrumentation and loading mechanism have been carried out. Development of a new oxygen potential sensor for oxide fuel pellets has been done as an elemental technology of irradiation for high burn-up fuels. As for post irradiation examination, the techniques for measuring of crack length using an alternating current potential drop method and machining of miniaturized specimen by the remote handling have been developed. A research on the blanket materials and components for thermonuclear fusion reactor ...
Brassica napus is an allotetraploid (AACC) formed from the fusion of two diploid progenitors, Brassica rapa (AA) and Brassica oleracea...Full Text Available
Neutral beam systems for the next generation of magnetic fusion devices will be based on negative ions. Development are progressing steadily, and large negative ion-based systems are prepared for JT60-U and LHD, and are being considered for ITER. An overview of the physics of the production, acceleration and neutralization of large negative ion beams is given. the present state of the art in Research and Development is also surveyed. (author). 55 refs., 10 figs., 1 tab.
Neutral beam systems for the next generation of magnetic fusion devices will be based on negative ions. Developments are progressing steadily, and large negative ion-based systems are under preparation for JT60-U and LHD, and are being considered for ITER. An overview of the physics of the production, acceleration and neutralization of large negative ion beams is given. The present state of the art in R and D is also surveyed. (Author).
BackgroundOur previous studies indicate that either PEP-1-superoxide dismutase 1 (SOD1) or PEP-1-catalase (CAT) fusion proteins protects myocardium from ischemia-reperfusion-induced...Full Text Available
Small unilamellar vesicles which form when gel-state long-chain phosphatidylcholines are mixed with micellar short-chain lecithins undergo an increase in size as the long-chain species melts to its liquid-crystalline form. Analysis of the vesicle population with quasi-elastic light scattering shows that the particle size increases from 90-A radius to greater than 5000-A radius. Resonance energy transfer experiments show total mixing of lipid probes with unlabeled vesicles only when the Tm of the long-chain phosphatidylcholine is exceeded. This implies that the large size change represents a fusion process. Aqueous compartments are also mixed during this transition. 31P NMR analysis of the vesicle mixtures above the phase transition shows a great degree of heterogeneity with large unilamellar particles coexisting with oligo- and multilamellar structures. Upon cooling the vesicles below the Tm, the original size distribution (e.g., small unilamellar vesicles) is ...
The change in concentrations of elements due to transmutations resulting from neutron irradiation in the first wall of the ARIES-IV conceptual fusion energy device were determined as a function of neutron dose. SiC burns out at a rate of about 0.5% per effective full power year. The largest impurity concentration is that of He, but several other elements burn in at rates of hundreds of appm/efpy.
Surface deposition probe techniques have been shown to be an effective means of determining the characteristics of the plasma edge region of magnetic confinement devices. Experimental results on ISX-B and EBT-S have led to a consistent picture of the edge plasma and the dominant impurity introduction mechanisms. This picture is supported by numerous other measurements and emphasizes the importance of concentrating several techniques on the complex problems of plasma fusion.
This paper presents the present status of R and D activities on plasma facing components for fusion reactors, such as International Thermonuclear Experimental Reactor (ITER) and fusion demonstration reactor (DEMO). The plasma facing components (PFCs) as typified by divertor and first wall components are subjected to high heat flux and particle flux from fusion plasma. It is essential for these components to have sufficient heat removal capability and robust structure against those loadings. JAEA has been carried out to develop the ITER-PFCs which consist of copper alloys and armor materials with high thermal conductivity, such as carbon fiber composites, tungsten and beryllium. The demonstration of the thermomechanical performance of the ITER-PFCs by using mock-ups has successfully been made under close mutual cooperation between the participant countries of ITER. Currently, the activity on the development of the ITER-PFCs ...
The new collaborative exploitation of the JET Facilities requires suitable technical tools and infrastructure measures to enable the Remote Participation of scientists from all European Fusion labs. Such measures are being gradually introduced. They comprise of a toolkit for Remote Data Access, Remote Computer Access and for teleconferencing, and of infrastructure measures that address network connectivity, network security, shared documentation and technical support.
The most important results of theoretical and experimental studies of plasmas, which have been achieved at the IPJ in Swierk and IPPLM in Warsaw recently, are presented. Studies of physical phenomena in PF discharges, development of diagnostic techniques and research on new plasma technologies, as performed at IPJ, have been summarized. Studies of dense magnetized plasmas, investigation of physics and applications of laser-produced plasmas; and research on the development of advanced diagnostic techniques for the EUROATOM fusion program, as performed at IPPLM, are also described.
Solutions have been found for the problems encountered with the coil power and switching systems of the International Fusion Superconducting Magnet Test Facility (IFSMTF). The coil power system provides the filtered dc sources (+- 12 V dc; 25,000 A) for charging and discharging the coils of the IFSMTF experiment. The switching system provides the means of transferring the coil current into a dump resistor when a rapid discharge of a coil is required due to a coil failure (quench) or other system abnormalities.
Several reactions producing odd-Z transactinide compound nuclei were studiedwith the 88-Inch Cyclotron and the Berkeley Gas-Filled Separator at the LawrenceBerkeley National Laboratory. The goal was to produce the same compound nucleus ator near the same excitation energy with similar values of angular momentum via differentnuclear reactions. In doing so, it can be determined if there is a preference in entrancechannel, because under these experimental conditions the survival portion of Swiatecki, Siwek-Wilcznska, and Wilczynski's"Fusion By Diffusion" model is nearly identical forthe two reactions. Additionally, because the same compound nucleus is produced, theexit channel is the same. Four compound nuclei were examined in this study: 258Db, 262Bh, 266Mt, and 272Rg. These nuclei were produced by using very similar heavy-ion induced-fusion reactions which differ only by one proton in the projectile or target nucleus ...
This overview of research conducted at ORNL in 1991 presents information on the subjects of biology, physics, and the environment. Specific topics include gene mutations in kidney disease, technology assessments in thermonuclear fusion, submarine hunting technology, ozone-safe refrigerants, optical data storage via surface enhanced raman spectroscopy, and waste mitigating microbes. (GHH)
This overview of research conducted at ORNL in 1991 presents information on the subjects of biology, physics, and the environment. Specific topics include gene mutations in kidney disease, technology assessments in thermonuclear fusion, submarine hunting technology, ozone-safe refrigerants, optical data storage via surface enhanced raman spectroscopy, and waste mitigating microbes. (GHH)
The study of the melting of combustible rods is of great importance for the safety analysis of nuclear reactors. Due to the special characteristics of the problem, a sharp interface between the solid and liquid region does not exist, but appears a 'mushy' region in which the material is partially melted. The Finite Element Method is employed here, together with a regularized enthalpy formulation. Finally, the results obtained are presented and discussed. (Author).
As part of a handbook on the efficient use of energy a chapter is included which is intended to give an appreciation of the principles and problems involved in the generation of nuclear power. The subject is discussed under the following headings: introductory nuclear physics; basic reactor physics; thermal reactors; fast reactors; fuel reserves and utilization; environmental considerations; nuclear fusion. (U.K.).
We study heavy physics effects on the Higgs production in #gamma##gamma# fusion using the effective Lagrangian approach. We find that the effects coming from new physics may enhance the standard model predictions for the number of events expected in the final states b-barb, WW, and ZZ up to one order of magnitude, whereas the corresponding number of events for the final state t-bart may be enhanced up to two orders of magnitude.
University research group with research areas: * Land based and submersible autonomous robots, (UUVs: AUVs and ROVs); * Controllers, electronics, sensor design and fusion, motion control; * Guidance and navigation of underwater vehicles; * AI, neural networks, fuzzy logic, subsumption control, behaviour based control; * Optical fibre and ultrasonic sensors for proximal object detection; * Robot arm control, visual servoing; * Imaging sonar applications; * Simulator development: UUV simulator; imaging sonar simulator; Aircraft/flight simulator.
At the RIKEN-RAL Muon Facility, ?- to ? sticking K? X-rays were observed for the first time taking advantage of the pulsed beam structure. The precision of the present measurements was insufficient to distinguish between theoretical models, however the observed K?/K? X-ray intensity ratio tends to be smaller than most of these theoretical predictions.
The statements given by the following people are included: Steven Dean, Edward Frieman, Zalman Shapiro, Lee Berry, Ronald Davidson, Kenneth Fowler, Melvin Gottlieb, and Tihiro Ohkawa. (MOW)
Some 43 papers were presented in 4 sections: Organ and bud culture of tree species (24 papers); Cell suspension and callus culture of tree species (11); Culture of haploid tissue of tree species and production of wood homozygotes (3); and Isolation, culture and somatic fusion of protoplasts as a means of somatic hybridization and genetic engineering (5).
At Livermore our hope and our intention is to make important contributions to global sustainability by basing both our scientific and technological research and our business practices on the principles of industrial ecology. Current efforts in the following fields are documented: global security, global ecology, energy for transportation, fusion energy, materials sciences, environmental technology, and bioscience.
Negative ions have attractive features as drivers for inertial confinement fusion, because they will avoid electron cloud effects, and could be efficiently photodetached to neutrals after the final focus, which could also be beneficial in heating warm dense matter targets. The halogens have large electron affinities, and thus should be able to produce high current densities of relatively robust negative ions. Recent experiments comparing chlorine beams to argon beams using the same source, extraction optics, and diagnostics have demonstrated that Cl"- beams can be produced with similar emittance to Ar"+ beams, and with about 34 the current density from the same configuration. The observed effective beam temperature of about 13eV, and the similarity of current densities show that negative halogen beams can meet the current density and emittance requirements of heavy ion fusion. The near equivalence of the Cl"- and Cl"++Cl_2"+ current densities ...
Selected neutron reaction nuclear data libraries and photon-atomic interaction cross section libraries for elements of interest to the IAEA's program on Fusion Evaluated Nuclear Data Library (FENDL) have been processed into MATXSR format using the NJOY system on the VAX4000 computer of the IAEA. This document lists the resulting multigroup data libraries. All the multigroup data generated are available cost-free upon request from the IAEA Nuclear Data Section. (author). 9 refs.
If the soft supersymmetry (SUSY) breaking masses and couplings are complex and cancellations do take place in the SUSY induced contributions to the fermionic electric dipole moments, then the CP- violating soft phases can drastically modify much of the known phenomenological pattern of the minimal supersymmetric standard model. In particular, the squark loop content of the dominant Higgs production mechanism at the large hadron collider, the gluon-gluon fusion mode, could be responsible for large corrections to the known cross sections. (15 refs).
It is shown that recuperator in which the thermal energy of particles is transformed into electric oue under drift in crossed fields is naturally coupled with dragontype magnetic confinement system, so the recuperation process can be initiated in the dragon magnetic field. A number of questions occuring under analysis of recuperator-dragon system is considered, including the dynamics of particle transfer to the recuperator, the share of particles entering the recuperator, the effect of rotational transform and the recuperation efficiency.
The motivation for this design study has been to identify magnet designs for useful magnetic fusion experiments which minimize capital cost. Some possibly useful novel design features have been identified. 5 refs., 6 figs., 3 tabs.
Histone-beta-galactosidase protein fusions were used to identify the domain of yeast histone 2B, which targets this protein to the nucleus. Amino acids 28 to 33 in H2B were required for nuclear localization...Full Text Available
Toroidicity Alfven Eigenmodes (TAE) in ITER can be driven unstable by two groups of energetic particles, the 3.5 MeV {alpha}-particle fusion products and the tangentially injected 1MeV beam ions. Stability conditions are established using the perturbative NOVA/NOVA-K codes. A quasi-linear diffusion model is then used to assess the induced redistribution of energetic particles.
Afterheat represents an important consideration in design of conceptual fusion power reactors, particularly during normal or unplanned shutdown. Afterheat calculations have been undertaken for various generic designs, but with special reference to the Culham DEMO reactor. These calculations have included the redistribution of heating by gamma ray transport. Selected temperature response calculations have been undertaken. (author).
We have previously shown that budded viruses of Bombyx mori nucleopolyhedrovirus (BmNPV) enter the cell cytoplasm but do not migrate into the nuclei of non-permissive Sf9 cells that support a high titer of Autographa californica multicapsid nucleopolyhedrovirus (AcMNPV) multiplication. Here we show, using the syncytium formation assay, that low-pH-triggered membrane fusion of BmNPV GP64 protein (Bm-GP64) is significantly lower than that of AcMNPV GP64 protein (Ac-GP64). Mutational analyses of GP64 proteins revealed that a single amino acid substitution between Ac-GP64 H155 and Bm-GP64 Y153 can have significant positive or negative effects on membrane fusion activity. Studies using bacmid-based GP64 recombinant AcMNPV harboring point-mutated ac-gp64 and bm-gp64 genes showed that Ac-GP64 H155Y and Bm-GP64 Y153H substitutions decreased and increased, respectively, the multiplication and cell-to-cell spread of progeny viruses. These results ...
There is a lot of interest in the studies that would help to understand whether there is a casual association between cancer and various types of molecular or cytogenetic damage detected in human cells. One major oncogenesis process is activation of proto-oncogenes by point mutations or chromosomal translocation. There are substantial evidence that indicates that the loss of heterozygosity of certain chromosomes is involved in human cancerogenesis. Our study aimed to elicit the possible association between cancer and DNA and cytogenetic abnormalities induced in lymphocytes of people bearing various categories of skin cancer cells. Fresh blood was collected by venipuncture from 25 individuals (including nine prior to cancer treatment). All patients were nonsmoking males, however 42.3 % of them were former smokers. Blood samples were divided into two parts and in the first part of samples cytogenetic studies were performed immediately, while from ...
The meiotic spindle in the oocyte is composed of microtubules and plays an important role during chromosome alignment and separation at meiosis. Polarized light microscopy (PLM) could be useful for a non-invasive evaluation of the meiotic spindle and may allow removal of nuclear structures without fluorochrome staining and ultraviolet exposure. In this study, PLM was used to assess its potential application in porcine reproductive technologies. The objectives of the present study were to assess the efficiency of PLM to detect microtubule-polymerized protein in in vitro-matured porcine oocytes; to examine its effects on the oocyte developmental competence; to select oocytes based on the presence of the meiotic spindle detected by PLM; and to assess the efficiency oocyte enucleation assisted...
Swollen basiodiospores of an adenine auxotroph of Phanerochaete chrysosporium were protoplasted with Novozyme 234 and transformed to prototrophy by using a plasmid containing the gene for an adenine biosynthetic enzyme from Schizophyllum commune. Transformation frequencies of 100 transformants per {mu}g of DNA were obtained. Southern blot analysis of DNA extracted from transformants demonstrated that plasmid DNA was integrated into the chromosomal DNA in multiple tandem copies. Analysis of conidia and basiodiospores from transformants demonstrated that the transforming character was mitotically and meiotically stable on both selective and nonselective media. Genetic crosses between double mutants transformed for adenine prototrophy and other auxotrophic strains yielded Ade{sup {minus}} progeny, which indicated that integration occurred at a site(s) other than the resident adenine biosynthetic gene.
Abstract Ultrastructural studies have shown that the formation of pigment glands in Gossypium hirsutum L. leaves is a lysigenous process, originating from a cluster of cells in the ground meristem. Various techniques were used here to investigate whether programmed cell death (PCD) plays a critical role in this developmental process. Nuclei of internal cells in the pigment gland-forming tissue were TUNEL-positive and DAPI-negative, suggesting that DNA cleavage is an early event and complete DNA degradation is a late event. Smeared bands and a lack of laddering after gel electrophoresis indicate that DNA cleavage is random. Ultrastructurally, secretory cells in the pigment glands become distorted, nuclei are densely stained, and chromosomes become condensed until completely degraded at late...
The results of an investigation into tailed nuclei (TN) and features of dose dependence on frequency of the binuclear cells with TN in human lymphocyte cultures by cytogenetic block method upon X-ray radiation dose are presented. The frequencies of metaphases with dicentric and ring chromosomes are investigated concurrent with TN formed upon completion of first postradiation mitosis. Frequency of the appearance of binuclear cells with nuclei having outgrowth into the cytoplasmic space and arises after first mitosis in human lymphocyte culture is linear-square dependent on the X-irradiation at doses from 0.0 to 4.0 Gy. Positive correlation between frequency of cells with tailed nuclei and frequency of metaphases of first mitosis having dicentric and rings was established. Apparently, formation such TN is connected with dicentric and rings
Over the decades, basic research in life sciences has profited greatly from the study of the small unicellular fungal species Saccharomyces cerevisiae. This yeast turned out to be key for the identification and understanding of molecular mechanisms that underlay the basic functions of all eukaryotic cells. These include, but are not limited to, the regulatory mechanisms behind cellular reproduction (cell cycle control), cellular morphogenesis (cell polarity, cytoskeleton and membrane trafficking) and the management of cellular information (chromosome biology, transcription and translation). Rapid access to genomic information of many yeast species, combined with bioinformatics analyses, provide information on the evolutionary history of yeasts and the molecular ancestry of their constituen...
From May, 1999 to August, 2006, we performed laparoscopic diagnosis and treatment for 103 cases of impalpable testes. Among those we found 5 cases of male pseudohermaphroditism of different etiologies. Three males presented by impalpable testes with ambiguous genitalia and 2 females presented by primary amenorrhea. All of them have 46-XY normal male chromosomal pattern. In the first 3 cases, the etiology was complete gonadal dysgenesis, and 2 cases with persistent Mullerian syndrome. Timed gonadectomy for the first case and laparoscopic orchiopexy for the other 2 cases were performed. For the other 2 female cases, the etiology was complete androgen insensitivity syndrome and laparoscopic bilateral orchiectomy was performed for both of them. All the procedures were done without complications with satisfactory results. PMID:18319558
The Lesch-Nyhan (LN) syndrome is a severe X chromosome-linked disease that results from a deficiency of the purine salvage enzyme hypoxanthine phosphoribosyltransferase (HPRT). The mutations leading to the disease are heterogeneous and frequently arise as de novo events. The authors have identified nucleotide alterations in 15 independently arising HPRT-deficiency cases by direct DNA sequencing of in vitro amplified HPRT cDNA. They also demonstrate that the direct DNA sequence analysis can be automated, further simplifying the detection of new mutations at this locus. The mutations include DNA base substitutions, small DNA deletions, a single DNA base insertion, and errors in RNA splicing. The application of these procedures allows DNA diagnosis and carrier identification by the direct detection of the mutant alleles within individual families affected by LN.
Genetic mapping is approached using the techniques of high resolution fluorescence in situ hybridization (FISH). This technology and the results of its application are designed to rapidly generate whole genome as tool box of expressed sequence to speed the identification of human disease genes. The results of this study are intended to dovetail with and to link the results of existing technologies for creating backbone YAC and genetic maps. In the first eight months, this approach generated 60--80% of the expressed sequence map, the remainder expected to be derived through more long-term, labor-intensive, regional chromosomal gene searches or sequencing. The laboratory has made significant progress in the set-up phase, in mapping fetal and adult brain and other cDNAs, in testing a model system for directly linking genetic and physical maps using FISH with small fragments, in setting up a database, and in establishing the validity and throughput of the system.
Abstract In the 1990s, significant efforts were invested in the research and development of food-grade expression systems in lactic acid bacteria (LAB). At this time, Lactococcus lactis in particular was demonstrated to be an ideal cell factory for the food-grade production of recombinant proteins. Steady progress has since been made in research on LAB, including Lactococcus, Lactobacillus and Streptococcus, in the areas of recombinant enzyme production, industrial food fermentation, and gene and metabolic pathway regulation. Over the past decade, this work has also led to new approaches on chromosomal integration vectors and host/vector systems. These newly constructed food-grade gene expression systems were designed with specific attention to self-cloning strategies, food-grade selection...
Purpose Evaluation of the all-trans retinoic acid (t-RA) effects on in vitro maturation (IVM) and in vitro fertilization (IVF) of immature mouse oocytes in the presence and absence of granulosa cell monolayer. Methods Denuded oocytes isolated from mice ovaries and matured in IVM medium alone (Control I), IVM medium in the presence of granulosa cells (Control II), IVM medium with t-RA (Experimental I) and IVM medium simultaneously with t-RA and granulosa cells (Experimental II). After 24?h, matured oocytes were fertilized in T6 medium and their development was followed until the blastocyst stage. Metaphase II oocytes ploidy were evaluated by chromosome counting. Results The t-RA group compared to the control groups showed no obvious abnormalities. Additionally maturation and embryo developm...
Data are presented to support the hypothesis that the initial step in the morphologic transformation of irradiated rodent (BALB/3T3) cells is a frequent cellular event involving a large fraction of the irradiated population. This process appears to involve DNA damage, but not to represent a targeted mutation in specific structural gene(s). Morphologic transformation and immortalization appear to be distinct steps in the overall process of transformation. In contradistinction to rodent cells, immortalization is a very rare event in human diploid cells which is induced at extremely low frequencies. The hypothesis is presented that immortality develops among clones of cells bearing stable chromosomal rearrangements which emerge during the proliferation of a population of radiation damaged cells.
In the present study, human neonatal fibroblasts were isolated from a two-month-old human male. The purpose of the present investigation was the analysis of the morphology (light and transmission electron microscopy), karyotype and growth characteristics of the human neonatal fibroblast cell culture B-HNF-1. Moreover, STR typing and mitochondrial DNA amplification and sequencing was also performed. Analysis of chromosomes count showed that B-HNF-1 cell culture is diploid and has normal male karyotype 46, XY, which was stable during cultivation. The transmission electron microscopy demonstrated the ultra-structure of the B-HNF-1 cells; they have typical morphological features of proteosynthesis-active cells. Large number of fibroblasts bearing different shapes and surface characteristics ad...
SNAP25 occurs on chromosome 20p12.2, which has been linked to schizophrenia in some samples, and recently linked to latent classes of psychotic illness in our sample. SNAP25 is crucial to synaptic functioning, may be involved in axonal growth and dendritic sprouting, and its expression may be decreased in schizophrenia. We genotyped 18 haplotype-tagging SNPs in SNAP25 in a sample of 270 Irish high-density families. Single marker and haplotype analyses were performed in FBAT and PDT. We adjusted for multiple testing by computing q values. Association was followed up in an independent sample of 657 cases and 411 controls. We tested for allelic effects on the clinical phenotype by using the method of sequential addition and 5 factor-derived scores of the OPCRIT. Nine of 18 SNPs had P values <...
The synapsin III gene, SYN3, which belongs to the family of synaptic vesicle-associated proteins, has been implicated in the modulation of neurotransmitter release and in synaptogenesis, suggesting a potential role in several neuropsychiatric diseases. The human SYN3 gene is located on chromosome 22q12-13, a candidate region implicated in previous linkage studies of schizophrenia. However, association studies of SYN3 and schizophrenia have produced inconsistent results. In this study, four SYN3 SNPs (rs133945 (-631 C>G), rs133946 (-196 G>A), rs9862 and rs1056484) were tested in three sets of totally 3759 samples that comprise 655 affected subjects and 626 controls in the Irish Case-Control Study of Schizophrenia (ICCSS), 1350 samples incorporating 273 pedigrees in the Irish Study of High D...
Amphiphysin is a protein concentrated in neuronal synapses and peripherally associated with neurotransmitter vesicles. It is expressed in many neurons of the central and peripheral nervous systems, in the adrenal medulla, in the anterior and posterior pituitary, in cell lines of the endocrine pancreas, and in spermatocytes. Its subcellular localization and tissue distribution indicate a potential involvement in mechanisms of regulated exocytosis. A role in the dynamic organization of the membrane-associated cytoskeleton is suggested by structural homology to the products of two yeast genes, RVS161 and RVS167, whose mutation results in an abnormal actin distribution, disturbs budding morphology, and impairs cell entry into stationary phase. Limited stretches of sequence similarity, including an SH3 domain, are also shared with other actin-binding proteins. Amphiphysin is the dominant autoantigen in paraneoplastic Stiff-Man syndrome, a neurological autoimmune disorder characterized by ...
Evidence suggests that insertion of the IS6110 element is not without consequence to the biology of Mycobacterium tuberculosis complex strains. Thus, mapping of multiple IS6110 insertion sites in the genome of biomedically relevant clinical isolates would result in a better understanding of the role of this mobile element, particularly with regard to transmission, adaptability and virulence. In the present paper, we describe a versatile strategy, referred to as GL-PCR, that amplifies IS6110-flanking sequences based on the construction of a genomic library. M. tuberculosis chromosomal DNA is fully digested with HincII and then ligated into a plasmid vector between T7 and T3 promoter sequences. The ligation reaction product is transformed into Escherichia coli and selective PCR amplification...
The human mitochondrial DNA (mtDNA) is a closed circular, 16,569-bp double-stranded DNA, encoding 13 genes whose protein products are subunits of the oxidative phosphorylation system required for synthesis of most of the ATP consumed by eukaryotic cells. Point mutations of the mtDNA that cause multi-tissue, loss-of-energy syndromes, called mitochondrial encephalomyopathies (e.g., MERRF and MELAS), have been identified. In addition, large-scale deletions of the human mtDNA have been identified and are the molecular bases for the neonatal and adolescent onset loss-of-energy syndromes Pearson and Kearns-Sayer, respectively. 5 refs., 1 fig.
Concerning heat transfer augmentation of an axisymmetric impinging jet using a perforated plate set, the bore of the hole in the plate for local and averge heat transfer rate, pitch, and effect of the distance between perforated plate and target plate were examined. Heat transfer augmentation was examined under the condition of 0.063 /ge/d/D /ge/0.200, 1.25 /ge/p/d /ge/4.00, Re is approximately equal to 18000, (where d is the bore of the hole in the plate, D is the axisymmetric nozzle outlet bore, p is the pitch of the perforated plate, and Re is the jet Reynolds number). The findings are as follows; The velocity of the small jet after passing the perforated plate is reduced, and resistance to disturbance is remarkably large. The small jet which is not at the center hole extends to the outside of the plate. The heat transfer rate at a stagnation point is high when the target plate is placed in the jet potential core area and that augmentation rate is approximately ...
The corrected transposition of the great arteries is an usual congenital cardiac malformation, which consists of transposition of great arteries and ventricular inversion, and which is caused by abnormal development of conotruncus and ventricular looping. High frequency of associated cardiac malformations makes it difficult to get accurate morphologic diagnosis. A total of 18 cases of corrected transposition of the great arteries is presented, in which cardiac catheterization and angiocardiography were done at the Department of Radiology, Seoul National University Hospital between September 1976 and June 1981. The clinical, radiographic, and operative findings with the emphasis on the angiocardiographic findings were analyzed. The results are as follows: 1. Among 18 cases, 13 cases have normal cardiac position, 2 cases have dextrocardia with situs solitus, 2 cases have dextrocardia with situs inversus and 1 case has levocardia with situs inversus. 2. Segmental sets are (S, L, L) in 15 ...
In the bacterial reversion assay with S. typhimurium TA98, TA100, TA1535 and TA1537, gamma irradiated hyaluronic acid (10 and 50 kGy) did not induce a significant increase in the number of revertant colonies in the presence of S9 metabolic activation system. In chromosomal aberration tests with CHO cells, gamma irradiated hyaluronic acid (10 and 50 kGy) did not result in an increase in the frequency of chromosomal aberrations. In vivo mouse micronucleus assay, gamma irradiated hyaluronic acid (10 and 50 kGy) did not show an increase in the frequency of polychromatic erythrocytes with micronuclei. These results indicate that hyaluronic acids irradiated at 10 and 50 kGy did not show any genotoxic effects under these experimental conditions. In order to evaluate their possible subacute toxicity, the male and female of ICR mouse were given to methanol extract of 50 kGy irradiated red ginseng and 20 kGy irradiated water extract of mistletoe for ...
The neuronal nicotinic acetylcholine receptor {alpha}7 subunit is a member of a family of ligand-gated ion channels, and is the only subunit know to bind {alpha}-bungarotoxin in mammalian brain. {alpha}-Bungarotoxin binding sites are known to be more abundant in the hippocampus of mouse strains that are particularly sensitive to nicotine-induced seizures. The {alpha}7 receptor is highly permeable to calcium, which could suggest a role in synaptic plasticity in the nervous system. Auditory gating deficiency, an abnormal response to a second auditory stimulus, is characteristic of schizophrenia. Mouse strains that exhibit a similar gating deficit have reduced hippocampal expression of the {alpha}7 subunit. We have cloned and sequenced the full length cDNA for the mouse {alpha}7 gene (Acra-7) and characterized its gene structure. The murine {alpha}7 shares amino acid identity of 99% and 93% with the rat and human {alpha}7 subunits, respectively. Using an interspecies backcross panel, the ...
Twenty-two landrace-derived inbred lines from the Spanish Barley Core Collection (SBCC) were found to display high levels of resistance to a panel of 27 isolates of the fungus Blumeria graminis that exhibit a wide variety of virulences. Among these lines, SBCC145 showed high overall resistance and a distinctive spectrum of resistance compared with the other lines. Against this background, the main goal of the present work was to investigate the genetic basis underlying such resistance using a doubled haploid population derived from a cross between SBCC145 and the elite spring cultivar Beatrix. The population was genotyped with the 1,536-SNP Illumina GoldenGate Oligonucleotide Pool Assay (Barley OPA-1 or BOPA1 for short), whereas phenotypic analysis was performed using two B. graminis isolates. A major quantitative trait locus (QTL) for resistance to both isolates was identified on the long arm of chromosome 6H (6HL) and accounted for ca. 60% of the phenotypic ...
Background. Through PSA screening the rate of prostate cancers detected at an early stage has increased significantly; thus a decrease in mortality can be expected in the near future. Despite all scientific efforts, however, the molecular mechanisms underlying the development and progression of prostate cancer remain poorly understood. Prostate cancer is a disease of aging men and epidemiological evidence supports a major contribution to its development through diet, lifestyle and environmental factors. Genetic instability is the basic phenomenon of tissue cell cancerisation. This instability can be hereditary or due to mutations and other chromosomal aberrations acquired during life. In recent years a large number of interesting data have been collected which show the relationships between focal atrophy and genetic instability of the prostate epithelia. Atrophy can be the result of prostatitis, ischemia as well as of oxidative stress (diet). Several ...
Transducin {alpha} subunits are members of a large family of G-proteins and play an important role in phototransduction in rod and cone photoreceptors. We report the localization of the human cone {alpha} transducin (GNAT2) gene using fluorescence in situ hybridization (FISH) on chromosome 1 in band p13. The recent assignment of a gene for Stargardt`s disease to the same chromosomal region by linkage analysis prompted us to investigate the possible role of GNAT2 in the pathogenesis of this disease. Stargardt`s disease is characterized by degeneration in late childhood or early adulthood of the macula of the retina, a region rich in cones. We screened patients with Stargardt`s disease, with or without peripheral cone involvement as monitored by the full-field ERG, for mutations in this gene. We investigated 66 unrelated patients including 22 with peripheral cone dysfunction for mutations in the coding region of the GNAT2 gene using polymerase ...
A 36-year-old woman underwent amniocentesis for advanced maternal age. The fetal karyotype had an extra dark staining G band on the long arm of chromosome 11 with no other identifiable abnormalities. FISH studies using a chromosome 11 paint probe confirmed the origin of the extra band. The abnormality was identified as a partial duplication of 11q: 46,XX dir dup (11)(q13.5q21) or (q21q23.1). The specific duplicated band could not be identified with certainty. Detailed fetal sonograms were normal. Family studies revealed the identical duplication in the mother but normal karyotypes in both maternal grandparents. The mother had strabismus and a short tongue frenulum which required surgical correction. Menses occurred late in adolescence and complete development of secondary sexual characteristics was delayed until adulthood. An infertility evaluation revealed duplication of the uterus, cervix, and vagina. An evaluation for metorrhagia identified ...
Outbreaks of disease attributable to human error or natural causes can provide unique opportunities to gain new information about host-pathogen interactions and new leads for pathogenesis research. Poststreptococcal glomerulonephritis (PSGN), a sequela of infection with pathogenic streptococci, is a common cause of preventable kidney disease worldwide. Although PSGN usually occurs after infection with group A streptococci, organisms of Lancefield group C and G also can be responsible. Despite decades of study, the molecular pathogenesis of PSGN is poorly understood. As a first step toward gaining new information about PSGN pathogenesis, we sequenced the genome of Streptococcus equi subsp. zooepidemicus strain MGCS10565, a group C organism that caused a very large and unusually severe epidemic of nephritis in Brazil. The genome is a circular chromosome of 2,024,171 bp. The genome shares extensive gene content, including many virulence factors, with genetically ...
Stargardt`s disease is inherited as an autosomal recessive condition characterized by a juvenile macular dystrophy. Genetic linkage analysis recently assigned the disease locus to chromosome 1p21-p13 with the best estimate for location of the gene near the locus D1S435. We performed linkage analysis in 34 North American families and 2 inbred families from the Kingdom of Saudi Arabia with 12 highly polymorphic markers on chromosome 1p flanking D1S435 between D1S207 and D1S223 and report significant linkage for all 12 markers with no evidence for genetic heterogeneity. Two-point linkage analysis demonstrated the Stargardt`s disease locus and D1S435 are linked with a maximum lod score of 17.17 at a recombination fraction of 1%. The markers UT851, D1S188, D1S424, UT2069, and D1S236 also demonstrated recombination fractions of 1% or less with two-point lod scores of 15.86, 21.93, 16.41, 20.36, and 17.37, respectively. To characterize this region ...
Carbon isotope discrimination (?(13) C) is considered a useful indicator for indirect selection of grain yield (GY) in cereals. Therefore, it is important to evaluate the genetic variation in ?(13) C and its relationship with GY. A doubled haploid (DH) population derived from a cross of two common wheat varieties, Hanxuan 10 (H10) and Lumai 14 (L14), was phenotyped for ?(13) C in the flag leaf, GY and yield associated traits in two trials contrasted by water availability, specifically, rain-fed and irrigated. Quantitative trait loci (QTLs) were identified by single locus and two locus QTL analyses. QTLs for ?(13) C were located on chromosomes 1A, 2B, 3B, 5A, 7A and 7B, and QTLs for other traits on all chromosomes except 1A, 4D, 5A, 5B and 6D. The population selected for high ?(13) C had an increased frequency of QTL for high ?(13) C, GY and number of spikes per plant (NSP) when grown under rain-fed conditions and only for high ?(13) C and NSP ...
The sequencing and detailed comparative functional analysis of genomes of a number of select botanical models open new doors into comparative genomics among the angiosperms, with potential benefits for improvement of many orphan crops that feed large populations. In this study, a set of simple sequence repeat (SSR) markers was developed by mining the expressed sequence tag (EST) database of sorghum. Among the SSR-containing sequences, only those sharing considerable homology with rice genomic sequences across the lengths of the 12 rice chromosomes were selected. Thus, 600 SSR-containing sorghum EST sequences (50 homologous sequences on each of the 12 rice chromosomes) were selected, with the intention of providing coverage for corresponding homologous regions of the sorghum genome. Primer pairs were designed and polymorphism detection ability was assessed using parental pairs of two existing sorghum mapping populations. About 28% of these new ...
Ewing's sarcoma is a small round-cell tumor typically arising in the bones, rarely in soft tissues, of children and adolescents. Ewing's sarcoma has retained the most unfavorable prognosis of all primary musculoskeletal tumors. Prior to the use of multi-drug chemotherapy, long-term survival was less than 10%. The development of multi-disciplinary therapy with chemotherapy, irradiation, and surgery has increased current long-term survival rates in most clinical centers to greater than 50%. In addition, the preferred method of tumor resection has changed; limb salvage has nearly replaced amputation of the affected limb. Limb salvage procedures can be performed in place of amputation without compromising patient survival rates. Recent studies have revealed that the pathognomonic translocations involving the EWS gene on chromosome 22 and an ETS-type gene, which is most commonly the Fli1 gene on chromosome 11, are implicated in more than 95% of ...
Duchenne and Becker muscular dystrophies are caused by defects of dystrophin, which forms a part of the membrane cytoskeleton of specialized cells such as muscle. It has been previously shown that the dystrophin-associated protein A1 (59-kDa DAP) is actually a heterogeneous group of phosphorylated proteins consisting of an acidic ({alpha}-A1) and a distinct basic ({beta}-A1) component. Partial peptide sequence of the A1 complex purified from rabbit muscle permitted the design of oligonucleotide probes that were used to isolate a cDNA for one human isoform of A1. This cDNA encodes a basic A1 isoform that is distinct from the recently described syntrophins in Torpedo and mouse and is expressed in many tissues with at least five distinct mRNA species of 5.9, 4.8, 4.3, 3.1, and 1.5 kb. A comparison of the human cDNA sequence with the GenBank expressed sequence tag (EST) data base has identified a relative from human skeletal muscle, EST25263, which is probably a human homologue of the ...
Two-dimensional calculations are performed to obtain the conversion efficiency of traveling wave direct energy convertor adopted in a conceptual design of field reversed configuration D-"3He fusion reactor ARTEMIS. For fusion-born 14.67MeV protons, the efficiency obtained is very small compared with that from one-dimensional analysis. This is because the effective electric field for deceleration of the proton is smaller due to distortion of potentials near girds used to excite the traveling wave and because some fractions of the incident proton beams are inevitably lost to the grids with high energy. To increase the efficiency, the potentials may have to be increased. It seems from the two-dimensional analysis performed here that the conversion efficiency obtainable is less than about 60% with the maximum potential of about 6MV, while the corresponding values from the one-dimensional analysis are about 80% and 1.5MV, respectively. (author).
An assessment of the cooling requirements for fusion reactor components, such as the first wall and limiter/divertor, was carried out using pressurized water as the coolant. In order to establish the coolant operating conditions, a survey of the literature on departure from nucleate boiling, critical heat flux, asymmetrical heating and heat transfer augmentation techniques was carried out. The experimental data and the empirical correlations indicate that thermal protection for the fusion reactor components based on current design concepts can be provided with an adequate margin of safety without resorting to either high coolant velocities, excessive coolant pressures, or heat transfer augmentation techniques. If, however, the future designs require heat transfer enhancement techniques, experimental verification would be necessary since no data on heat transfer augmentation techniques exist for complex geometries, especially under ...
Liquid metal cooling for the first wall and blanket of a magnetic confinement fusion reactor has various advantages. However, it has the disadvantages of large magnetohydrodynamic pressure drops and heat transfer deterioration under a strong magnetic field. Thus, the present authors have proposed cooling with a helium-lithium annular mist flow as well as the cooling with a liquid metal boiling flow, and as fundamental studies, investigated the effect of a magnetic field on the flow characteristics and heat transfer of liquid metal two-phase systems since the 1970s. In the present paper we summarize the important findings obtained from our experimental studies for (i) an air-mercury stratified flow in a horizontal rectangular channel, (ii) a helium-lithium annular mist flow in a horizontal rectangular channel, (iii) the mercury pool boiling on a horizontal surface, and (iv) air-mercury upward flows in a vertical circular tube. Based on the results, the research ...
Liquid metal cooling for the first wall and blanket of a magnetic confinement fusion reactor has various advantages. However, it has the disadvantages of large magnetohydrodynamic pressure drops and heat transfer deterioration under a strong magnetic field. Thus, the present authors have proposed cooling with a helium-lithium annular mist flow as well as the cooling with a liquid metal boiling flow, and as fundamental studies, investigated the effect of a magnetic field on the flow characteristics and heat transfer of liquid metal two-phase systems since the 1970s. In the present paper we summarize the important findings obtained from our experimental studies for (i) an air-mercury stratified flow in a horizontal rectangular channel, (ii) a helium-lithium annular mist flow in a horizontal rectangular channel, (iii) the mercury pool boiling on a horizontal surface, and (iv) air-mercury upward flows in a vertical circular tube. Based on the results, the research ...
A curved crystal X-ray spectrographs of reflection type spherical geometry was required based on the Johann scheme. Due to their high efficiency and resolution, X-ray spectrographs of focusing spectrograph spatial resolution are suitable for detecting weak X-ray spectra in spectrometers for laser fusion research. Spherically bent mica crystal with a radius of curvature of 380 mm was used in the spectrometer. The Bragg angle of the crystal analyzer was 51 degree. The image plate was employed to obtain high spatial resolution and a narrow spectral band width, with an effective area of 30 mm x 80 mm. The designed optical path of the X-ray spectrometer beam was 980 mm long from the source to the crystal and the detector. The first experiment was carried out at the 20 J energy laser facility of Research Center of Laser Fusion, China Academy of Engineering Physics. X-ray spectra in an absolute intensity scale were obtained from Al laser-produced ...
During the past 2 yr, significant progress has been made in several areas related to the safety and environmental (S and E) aspects of inertial fusion energy (IFE). An updated methodology has been developed, and accident analyses have been performed for two IFE conceptual power plants and a target fabrication facility. Parallel to the consequence analyses of different accident scenarios, ongoing studies of accident initiating events are being used to support safety assessment and create a basic framework of types of events to consider in future risk characterization of new plant designs. Target designers/fabrication specialists have been provided with ranking information related to the S and E characteristics of candidate target materials. We have revisited waste management options for IFE, introducing the concept of clearance versus the traditional shallow land burial. A brief summary of results in each of these activities is given, and plans for future work are ...
Analyses have been performed of the potential consequences to the public of hypothetical loss-of-coolant accidents in conceptual fusion power plant designs. In order to establish upper bounds to the consequences of such events, a case has been studied in which total loss of all active cooling has been assumed, with no remedial intervention for the duration of the accident sequence. The analyses are based on three conceptual power plant designs, two of them similar to those assumed in the earlier safety and environmental assessment of fusion power (SEAFP) study (Raeder et al., 1995), with updating of assumed structural materials. The three models studied provide a broad range of design options. In all cases the decay-heat driven temperature transients are well below the level at which structural melting would begin. Based on conservative assumptions, mobilisation, release and dose calculations show that potential maximum doses to the public are ...
The use of deuterium-tritium fuel in the Compact Ignition Tokamak will require applying remote handling technology for ex-vessel maintenance and replacement of machine components. Highly activated and contaminated components of the fusion devices auxiliary systems, such as diagnostics and RF heating, must be replaced using remotely operated maintenance equipment in the test cell. In-vessel remote maintenance included replacement of divertor and first wall hardware, faraday shields, and for an in-vessel inspection system. Provision for remote replacement of a vacuum vessel sector, toroidal field coil or poloidal field ring coil was not included in the project baseline. As a result of recent coil failures experienced at a number of facilities, the CIT project decided to reconsider the question of remote recovery from a coil failure and, in January of 1990, initiated a coil replacement study. This study focused on the technical requirements and impact on ...
Taking the development of large current, negative ion sources which is in progress aiming at nuclear fusion reactors and the development of high luminance ion sources planned as a part of the Omega Project as the examples, the technology for generating high power ion beams is explained. Both these projects are positioned at the limit of the present technology of high power ion beam application as their targeted beam power reaches several tens MW. Consequently, the requirement for the ion sources is severe, and in particular, the generation of the ion beams having large current density with good convergence is beyond all precedents. The application of high power ion sources has been realized as the neutral beam injectors for large tokamaks. Also the hydrogen negative ion source of large current and the electrostatic acceleration technology for negative ion beams have been developed. Large plasma sources, the method of generating negative ions and the extraction of ...
Since the first round of conceptual fusion reactor designs in 1973 - 1974, there has been considerable progress in design improvement. Two recent tokamak designs of the Wisconsin and Culham groups, with increased plasma beta and wall loading (power density), lead to more compact reactors with easier maintenance. The Reference Theta-Pinch Reactor has undergone considerable upgrading in the design of the first wall insulator and blanket. In addition, a conceptual homopolar energy storage and transfer system has been designed. In the case of the mirror reactor, there are design changes toward improved modular construction and ease of handling, as well as improved direct converters. Conceptual designs of toroidal-multiple-mirror, liner-compression, and reverse-field pinch reactors are also discussed. A design is presented of a toroidal multiple-mirror reactor that combines the advantages of steady-state operation and high-aspect ratio. The liner-compression reactor ...
Radiation damage of the final optical components in an Inertial Confinement Fusion (ICF) reactor is a crucial issue for development of a laser-fusion reactor. To some extent, this problem will be encountered in the National Ignition Facility (NIF), but there, the integrated radiation dose will be considerably less than that encountered in a future reactor. This extremely harsh radiation environment necessitates shielding the ICF optics from direct neutron and x-ray bombardment. Several approaches have been suggested, such as the use of grazing incidence metal mirrors or fused silica wedge deflectors. While metal mirrors can withstand a larger radiation dose, their focusing qualities pose problems. Therefore wedge deflectors, originally suggested by Lawrence Livermore National Laboratory (LLNL) staff, represent a promising alternative. Radiation hardening of the fused silica deflectors using a new combined thermal/optical annealing approach is ...
A critical issues study of a symmetric illumination, direct drive laser fusion reactor called SIRIUS has been conducted. In particular, the uniformity requirements for direct drive targets have been assessed and it is shown that respectable gains (more than 60) could be obtained at modest (2MJ) KrF laser energies. Previous ICF cavity designs have been examined for use in a symmetric illumination geometry and features from several designs have been combined into a dry wall cavity design with a radius of 8 meters. Neutronic and photonic analysis shows that the present SIRIUS cavity design can breed sufficient tritium (breeding ratio = 1.17) even with 32 laser ports penetrating the cavity. However, it was found that there are a few critical issues that remain to be solved before a self-consistent reactor design could be initiated. Radiation damage to final optics, thermal performance of SiC tiles on the SIRIUS cavity wall, and performance of direct drive targets to ...
The fusion materials program has little irradiation effects data at temperatures from 100 to 350 degree C. Near-term machines such as the International Thermonuclear Engineering Reactor (ITER) will expose materials to neutron doses of 38 to 50 dpa at 150 degree C or less. The data base for structural materials must be extended into this range. Also, lower temperatures are needed to investigate the lower bound for tritium release from solid breeder materials. A low temperature test vehicle is proposed for the Fast Flux Test Facility (FFTF), which will provide test temperatures of 100 to 350 degree C. An 8.5-cm dia. by 100-cm test volume will be instrumented to collect temperature data and provide feedback for control. The spectrum and flux will provide accelerated damage accumulation for structural materials testing and the best available approximation of fusion reactor conditions for solid breeder materials testing. Breeder samples can be ...
A technique has been developed for high resolution alpha particle spectroscopy from track length determination in CR-39 plastic. On individual tracks an energy resolution deltaE close to the range straggling limit is obtainable. For 6 MeV alpha-particle deltaE is proportional 35 keV on individual particles and for groups of particles deltaE proportional 20 keV can be achieved using certain data selection criteria. At 100 keV on individual particles deltaE is proportional 20 keV. The analysis requires 1) a knowledge of the track-etch rate (Vsub(T))-range relationship and 2) a theoretical understanding of alpha-particle track structure in CR-39 as a function of particle energy, dip angle and degree of etching. The structure of alpha-particle etched tracks in CR-39 is described and two methods of analysis discussed. Examples are given of the resolution attainable on tracks of alpha-particles as natural decay energy and from alpha-particles generated in laser driven deuterium and tritium ...
The survivability of the final optic, which must sit in the line of sight of high-energy neutrons and gamma rays, is a key issue for any laser-driven inertial fusion energy (IFE) concept. Previous work has concentrated on the use of reflective optics. Here, we introduce and analyze the use of a transmissive final optic for the IFE application. Our experimental work has been conducted at a range of doses and dose rates, including those comparable to the conditions at the IFE final optic. The experimental work, in conjunction with detailed analysis, suggests that a thin, fused silica Fresnel lens may be an attractive option when used at a wavelength of 351 nm. Our measurements and molecular dynamics simulations provide convincing evidence that the radiation damage, which leads to optical absorption, not only saturates but that a 'radiation annealing' effect is observed. A system-level description is provided, including Fresnel lens and phase plate designs.
High precision, fast computation speed, as well as a good capability of fault tolerant and reconstruction are required more and more for spacecraft attitude determination system. To realize the above requirement, an approach was presented to the synthesis of federated filters using sigma point technique. In this algorithm, the sigma point technique brought the algorithm a high precision, while the federated structure significantly enhanced the filters' capability of multi-rate information fusion, fault tolerance, and system modularity. Within consideration of computation consumption, a simple information-sharing formulation was derived to adapt to the special property of sigma point distribution, and a dynamical information sharing strategy for multi-rate fusion was developed. A numerical simulation example was employed to give the algorithm a test, where the simulated system contained a suit of gyroscopes; a three-axis magnetometer and a sun ...
First structural wall material (FSW) materials in inertial fusion energy (IFE) power reactors will be irradiated under typical repetition rates of 1-10 Hz, for an operation time as long as the total reactor lifetime. The main objective of the present work is to determine whether a continuous-pulsed (CP) approach can be an efficient method in modeling the pulsed activation process for operating conditions of FSW materials. The accuracy and practicability of this method was investigated both analytically and (for reaction/decay chains of two and three nuclides) by computational simulation. It was found that CP modeling is an accurate and practical method for calculating the neutron-activation of FSW materials. Its use is recommended instead of the equivalent steady-state method or the exact pulsed modeling. Moreover, the applicability of this method to components of an IFE power plant subject to repetition rates lower than those of the FSW is still being studied. The ...
The irradiation behavior of Li{sub 2}TiO{sub 3} under a fusion reactor environment was simulated by simultaneous irradiation of Li{sub 2}TiO{sub 3} by the triple ion beams and the respective single ion beams of O{sup 2+}, He{sup +} and H{sup +}. The microstructural changes in Li{sub 2}TiO{sub 3} caused by the irradiation were measured by FT-IR photoacoustic spectroscopy. The results suggest that the amount of TiO{sub 2} formed is proportional to the dpa and that the method of irradiation does not affect the dependence of formation of TiO{sub 2}. On the other hand, the amount of defects and/or radiolytic products generated by irradiation, which is considered to trap hydrogen near the surface, is found to be affected by the method of irradiation. Such phenomena are believed to affect the tritium release behavior from Li{sub 2}TiO{sub 3}, and durability of Li{sub 2}TiO{sub 3} and compatibility of Li{sub 2}TiO{sub 3} with other components of the breeder blanket such as ...
The irradiation behavior of Li_2TiO_3 under a fusion reactor environment was simulated by simultaneous irradiation of Li_2TiO_3 by the triple ion beams and the respective single ion beams of O"2"+, He"+ and H"+. The microstructural changes in Li_2TiO_3 caused by the irradiation were measured by FT-IR photoacoustic spectroscopy. The results suggest that the amount of TiO_2 formed is proportional to the dpa and that the method of irradiation does not affect the dependence of formation of TiO_2. On the other hand, the amount of defects and/or radiolytic products generated by irradiation, which is considered to trap hydrogen near the surface, is found to be affected by the method of irradiation. Such phenomena are believed to affect the tritium release behavior from Li_2TiO_3, and durability of Li_2TiO_3 and compatibility of Li_2TiO_3 with other components of the breeder blanket such as structural materials in the fusion reactor system under ...
Effect of Limestone, iron ore and red mud as a flux for hot coal gasification wastes was examined as they are regarded easily available, pollution-less and less costly. (1) Fusion behavior of ash-iron ore mixture and ash-limestone mixture approximately coincided with that of the reagent; red mud with low iron purity also coincided when the addition was less than 40%. (2) According to a microscopic observation, localized melting of the ash was observed even at 900 - 950/sup 0/C which was lower than the mpt. by almost more than 100/sup 0/C, which was attributed to the formation of iron-based compound. (3) The softening point reduced down to 1000 - 1050/sup 0/C irrespective of type of ash or ion-based flux; they were in the form of slurry; it formed a slurry state by the localized melting of ashes. (4) At above mpt., most of the ash component minerals are liquid and evaporation of CO/sub 2/ or any low boiling point component gets faster. (8 figs, 2 tabs, 7 refs)
Displacements per atom (DPA) is a widely used damage unit for displacement damage in nuclear materials. Calculating the DPA for SiC irradiated in a particular facility requires a knowledge of the neutron spectrum as well as specific information about displacement damage in that material. In recent years significant improvements in displacement damage information for SiC have been generated, especially the energy required to displace an atom in an irradiation event and the models used to describe electronic and nuclear stopping. Using this information, numerical solutions for the displacement functions in SiC have been determined from coupled integro-differential equations for displacements in polyatomic materials and applied in calculations of spectral-averaged displacement cross sections for SiC. This procedure has been used to generate spectrally averaged displacement cross sections for SiC in a number of reactors used for radiation damage testing of fusion ...
Displacements per atom (DPA) is a widely used damage unit for displacement damage in nuclear materials. Calculating the DPA for SiC irradiated in a particular facility requires a knowledge of the neutron spectrum as well as specific information about displacement damage in that material. In recent years significant improvements in displacement damage information for SiC have been generated, especially the energy required to displace an atom in an irradiation event and the models used to describe electronic and nuclear stopping. Using this information, numerical solutions for the displacement functions in SiC have been determined from coupled integro-differential equations for displacements in polyatomic materials and applied in calculations of spectral-averaged displacement cross sections for SiC. This procedure has been used to generate spectrally averaged displacement cross sections for SiC in a number of reactors used for radiation damage testing of fusion ...
Technologies producing high power negative ion beams have been highly developed in these years at JAERI for use in neutral beam injectors for heating the thermonuclear fusion plasmas. At present, it is possible to produce multi-ampere H-/D- ion beams quasi-continuously at energies more than a few hundred keV with a good beam optics of beamlet divergence of a few milli-radian. Based on these technologies, two R and D projects have been initiated; one is to develop a 22A/500keV/10s D- ion source for the neutral beam injector for JT-60U, and the other is to develop a 1A/1MeV/60s H- ion source to demonstrate high current negative ion acceleration up to the energy of 1MeV, the energy required for the neutral beam injector for International Thermonuclear Experimental Reactor (ITER). (author).
The generation of fusion power from the Fast-Liner Reactor (FLR) concept envisages the implosion of a thin (3-mm) metallic cylinder (0.2-m radius by 0.2-m length) onto a preinjected plasma. This plasma would be heated to thermonuclear temperatures by adiabatic compression, pressure confinement would be provided by the liner inertia, and thermal insulation of the wall-confined plasma would be established by an embedded azimuthal magnetic field. A 2- to 3-mu s burn would follow the approx. 10"4 m/s radial implosion and would result in a thermonuclear yield equal to 10 to 15 times the energy initially invested into the liner kinetic energy. For implosions occurring once every 10 s a gross thermal power of 430 MWt would be generated. The results of a comprehensive systems study of both physics and technology (economics) optima are presented. Despite unresolved problems associated with both the physics and technology of the FLR, a conceptual power plant design is ...
A novel single-chain immunotoxin was constructed by combining a CD33-specific single chain Fv (scFv) antibody fragment with an engineered variant of Pseudomonas exotoxin A (ETA). The variant toxin carries the KDEL peptide at its C-terminus, a cellular peptide mediating improved retrograde transport to the endoplasmic reticulum. The purified recombinant fusion protein induced potent apoptosis of the human myeloid cell lines U937, HL-60 and THP-1. Up to 98% of U937 cells were eliminated after treatment for 72 h with a single dose of 500 ng/ml (c. 7 nmol/l). Killing was antigen-specific and occurred by apoptosis. A control protein, consisting of a CD19-specific scFv antibody fragment fused to the ETA-KDEL toxin, failed to induce death of the CD19-negative cell lines U937, HL-60 and THP-1. The CD33-ETA toxin also mediated apoptosis of fresh patient-derived acute myeloid leukaemia cells from bone marrow and peripheral blood. The pronounced antigen-restricted ...
A computational procedure is proposed to perform uncertainty analysis for the calculation of the isotopic inventory and radiological quantities obtained as a linear function of it, due to uncertainties in the activation cross sections. The method is applied to determine the uncertainty of the calculated shallow burial index (SBI) from activated type 304 stainless steel (SS) in the most neutron-exposed zone of the HYLIFE-II vessel structure. Results are obtained by means of an element-by-element study. Some other types of steel are also investigated for comparison purposes. The SS304 is confirmed to be the most promising steel option. 16 refs., 2 tabs.
A development history and current status evaluation are presented for nuclear-thermal rocket propulsion systems applicable to interplanetary flight. While the most advanced current chemical rocket engines, such as the SSMEs of the Space Shuttle, produce specific impulses of the order of 450 secs, a nuclear-thermal rocket engine tested at Los Alamos in 1969 generated 845 secs; such specific impulse improvements could represent weeks or months of interplanetary travel time. Attention is given to the achievements of the historical Nuclear Engine for Rocket Vehicle Application, Helios, and Orion design programs, as well as to the current Vehicle for Interplanetary Space Transportation Applications, which is fusion-based.
Superconducting magnetic and inertial energy pulsed power systems are being developed for future theta-pinch, Tokamak, and laser fusion applications. The short term requirements for these applications are discussed along with present day accomplishments. Areas requiring a research and development effort are examined in detail. Subjects discussed include stresses, energy loss factors, conductor metallurgy, cryogenic requirements, and electrical limitations of superconducting magnetic storage systems; costs, applications, and present technology of homopolar systems; and switching problems associated with both systems.
We analyse in detail the SL(2, R) black hole by extending standard techniques of Kac-Moody current algebra to the non-compact case. We construct the elements of the ground ring and exhibit W_#infinity# type structure in the fusion algebra of the discrete states. As a consequence, we can identify some of the exactly marginal deformations of the black hole. We show that these deformations alter not only the spacetime metric but also turn on non-trivial backgrounds for the tachyon and all of the massive modes of the string. (orig.).
An algorithm is proposed which treats the ECH generated potential in a self-consistent way, by extending the Monte-Carlo Fokker-Planck method used by Murakami [S. Murakami et al., Proc. 17th IAEA Fusion Energy Conference, Yokohama, 1998 (International Atomic Energy Agency, Vienna, in press), paper CN-69/TH2/1]. The additional physics is expected to influence the transport of both thermal and suprathermal electrons in a helical toroidal system. (author)
The vacuum polarization splitting of the M-shell states in muonic hydrogen can have a profound influence on the muonit de-excitation cascade in deuterium and tritium targets. The cascade also shows sensitive dependence on the precise rate of transfer processes between certain excited muonic deuterium and tritium atoms. Recent experimental data, where a much greater population of the (d..mu..) qs state (1/sub 1//sub //sub s/) was found than previously predicted, can be explained if the transfer rates from the (d..mu..) M-shell are assumed to be strongly suppressed.
The classification of rational conformal field theories is essentially equivalent to the classification of all possible four-point functions for the primary fields of the theories. An interesting set of parameters appearing in the latter classification is given by the number and the positions of so-called apparent singularities of the differential equations which are obeyed by the four-point functions. The subject of this paper is a detailed analysis of the role played by these parameters. In particular the restrictions imposed on them by general principles of two-dimensional conformal field theory are worked out, and the implications on the classification programme are discussed. (orig.).
A helium-3 proportional detector was equipped with the experiment of Liaw-type electrolytic cell contained eutectic LiCl-KCl molten salt saturated by LiD electrolytic to collect the informations of the rate and the energy distribution of possible neutron produced during the electrolysis processes. For long time monitoring, the significant reproducible neutron bursts appeared at several runs of cells during electrolytic processing. The neutron counting rate increased about a factor of two above the level of the background measurement. The pulse height signals were verified of neutron energy ranging from thermal up to 350 keV. (author).
Self-magnetically insulated, high-voltage transmission lines are used in inertial confinement fusion particle accelerators in order to transmit power from the vacuum insulator to the diode. This paper describes a time-dependent 2-D code (MITL) for calculating (for planar or triplate geometries) the motion of test electrons through the tapered input or output convolutes of such lines. MITL results show that the electron canonical momentum in the direction of the flow changes as the electron passes through the convoluted geometry; it is suggested that these electrons lead to losses observed in long self-magnetically insulated lines.
Fluidized bed technology was experimentally evaluated for the combustion and gasification of cotton gin waste. The isothermal bed temperatures in the reactors could be maintained below the ash fusion point of the waste. Raw stripper harvested cotton gin trash could be metered directly into the fluidized-bed reactors indicating that little feed preparation is required. H and CO were the primary products of gasification, and approximately 3200-400 Btu of gas were produced per lb of cotton gin waste. These techniques offer the potential of providing small-scale energy conversion systems for use on farms.
The effect of the rare earth element, yttrium, on the mechanical properties of 9Cr-2WVTa low active martensite steel for fusion reactor was studied and the metallurgical behavior of yttrium in the steel was primarily analyzed. The results show that it is easy for yttrium to aggregate and form the blocky yttrium rich inclusions in the steel, which can dissever the continuity of the matrix and produce micro-cracks for fracture. The yttrium rich inclusions were distributed along the rolling direction, which made the fracture surface delaminated in the tensile and impact samples, and reduced the mechanical properties of the steel. (authors)
An experimental verification for long-term performance of a Pd-Ag permeation in ITER tritium fusion cleanup units (FCU) is needed. In addition, information is required on the influence of tritium and {sup 3}He decay on the physical and chemical properties of Pd-Ag alloys (V-1). The results of the investigations of alloys (V-1) (mechanical properties and microstructure) after long-term usage exposition in tritium are given in this report. The experimental conditions (temperature, pressure, clearance, {sup 3}He concentrations) and the previous conclusions on the V-1 alloy performance are presented. (orig.).
The paper provides a brief description of the fuel characterization for Fast Breeder Test Reactor (FBTR) and Prototype Fast Breeder Reactor (PFBR). The development and characterization of mechanical properties of Alloy D9 clad and wrapper tubes are discussed. The problems associated with fusion welding of Alloy D9 are outlined. Non-destructive characterization of cladding tubes by optimum encircling eddy current probes, on-line and off-line neural network methods is presented. Both the on-line and off-line neural network methods could readily detect and size defects specified by the designers
The centroid and envelope dynamics of a high-intensity charged particle beam are investigated as a beam smoothing technique to achieve uniform illumination over a suitably chosen region of the target for applications to ion-beam-driven high energy density physics and heavy ion fusion. The motion of the beam centroid projected onto the target follows a smooth pattern to achieve the desired illumination, for improved stability properties during the beam-target interaction. The centroid dynamics is controlled by an oscillating "wobbler", a set of electrically-biased plates driven by RF voltage. __________________________________________________
sup(99m)Tc-MDP bone scintigraphy was performed on patients who received muscle-pedicle bone graft. In each of the bone head and the bone graft, a time-activity curve was obtained. In this muscle-pedicle bone graft, active revascularization and marked osteogenesis, which suggested rapid bone repairing, were observed. The bone scintigraphy was considered to be useful in observing the result of bone grafts, blood circulation, and time of bone fusion, and of value for early detection of secondary changes.