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1

The Universal Protein Resource (UniProt)  

PubMed Central

The ability to store and interconnect all available information on proteins is crucial to modern biological research. Accordingly, the Universal Protein Resource (UniProt) plays an increasingly important role by providing a stable, comprehensive, freely accessible central resource on protein sequences and functional annotation. UniProt is produced by the UniProt Consortium, formed in 2002 by the European Bioinformatics Institute (EBI), the Protein Information Resource (PIR) and the Swiss Institute of Bioinformatics (SIB). The core activities include manual curation of protein sequences assisted by computational analysis, sequence archiving, development of a user-friendly UniProt web site and the provision of additional value-added information through cross-references to other databases. UniProt is comprised of three major components, each optimized for different uses: the UniProt Archive, the UniProt Knowledgebase and the UniProt Reference Clusters. An additional component consisting of metagenomic and environmental sequences has recently been added to UniProt to ensure availability of such sequences in a timely fashion. UniProt is updated and distributed on a bi-weekly basis and can be accessed online for searches or download at .

2007-01-01

2

The UniProtKB/Swiss-Prot Tox-Prot program: a central hub of integrated venom protein data  

PubMed Central

Animal toxins are of interest to a wide range of scientists, due to their numerous applications in pharmacology, neurology, hematology, medicine, and drug research. This, and to a lesser extent the development of new performing tools in transcriptomics and proteomics, has led to an increase in toxin discovery. In this context, providing publicly available data on animal toxins has become essential. The UniProtKB/Swiss-Prot Tox-Prot program (http://www.uniprot.org/program/Toxins) plays a crucial role by providing such an access to venom protein sequences and functions from all venomous species. This program has up to now curated more than 5000 venom proteins to the high-quality standards of UniProtKB/Swiss-Prot (release 2012_02). Proteins targeted by these toxins are also available in the knowledgebase. This paper describes in details the type of information provided by UniProtKB/Swiss-Prot for toxins, as well as the structured format of the knowledgebase.

Jungo, Florence; Bougueleret, Lydie; Xenarios, Ioannis; Poux, Sylvain

2012-01-01

3

EBI/SIB/PIR: UniProt  

NSDL National Science Digital Library

The Universal Protein Resource, UniProt, "is the world's most comprehensive catalog of information on proteins." The Getting Started, Searches/Tools, and Databases sections are the true gems of the site. After getting acquainted with the trove of information and data offered by UniProt, users can then begin to search for various protein sequences and data collection via a well-organized searchable database organized by Classification, Function, Property and more. Also available for visitors is the ability to download some or all of the UniProt database. Other resources include a documents section that provides visitors with a user's manual and various technical information guides regarding the databases.

4

The Universal Protein Resource (UniProt) 2009  

PubMed Central

The mission of UniProt is to provide the scientific community with a comprehensive, high-quality and freely accessible resource of protein sequence and functional information that is essential for modern biological research. UniProt is produced by the UniProt Consortium which consists of groups from the European Bioinformatics Institute, the Protein Information Resource and the Swiss Institute of Bioinformatics. The core activities include manual curation of protein sequences assisted by computational analysis, sequence archiving, a user-friendly UniProt website and the provision of additional value-added information through cross-references to other databases. UniProt is comprised of four major components, each optimized for different uses: the UniProt Archive, the UniProt Knowledgebase, the UniProt Reference Clusters and the UniProt Metagenomic and Environmental Sequence Database. One of the key achievements of the UniProt consortium in 2008 is the completion of the first draft of the complete human proteome in UniProtKB/Swiss-Prot. This manually annotated representation of all currently known human protein-coding genes was made available in UniProt release 14.0 with 20 325 entries. UniProt is updated and distributed every three weeks and can be accessed online for searches or downloaded at www.uniprot.org.

2009-01-01

5

Automatically extracting functionally equivalent proteins from SwissProt  

PubMed Central

Background There is a frequent need to obtain sets of functionally equivalent homologous proteins (FEPs) from different species. While it is usually the case that orthology implies functional equivalence, this is not always true; therefore datasets of orthologous proteins are not appropriate. The information relevant to extracting FEPs is contained in databanks such as UniProtKB/Swiss-Prot and a manual analysis of these data allow FEPs to be extracted on a one-off basis. However there has been no resource allowing the easy, automatic extraction of groups of FEPs for example, all instances of protein C. We have developed FOSTA, an automatically generated database of FEPs annotated as having the same function in UniProtKB/Swiss-Prot which can be used for large-scale analysis. The method builds a candidate list of homologues and filters out functionally diverged proteins on the basis of functional annotations using a simple text mining approach. Results Large scale evaluation of our FEP extraction method is difficult as there is no gold-standard dataset against which the method can be benchmarked. However, a manual analysis of five protein families confirmed a high level of performance. A more extensive comparison with two manually verified functional equivalence datasets also demonstrated very good performance. Conclusion In summary, FOSTA provides an automated analysis of annotations in UniProtKB/Swiss-Prot to enable groups of proteins already annotated as functionally equivalent, to be extracted. Our results demonstrate that the vast majority of UniProtKB/Swiss-Prot functional annotations are of high quality, and that FOSTA can interpret annotations successfully. Where FOSTA is not successful, we are able to highlight inconsistencies in UniProtKB/Swiss-Prot annotation. Most of these would have presented equal difficulties for manual interpretation of annotations. We discuss limitations and possible future extensions to FOSTA, and recommend changes to the UniProtKB/Swiss-Prot format, which would facilitate text-mining of UniProtKB/Swiss-Prot.

McMillan, Lisa EM; Martin, Andrew CR

2008-01-01

6

UniProt Knowledgebase: a hub of integrated protein data  

PubMed Central

The UniProt Knowledgebase (UniProtKB) acts as a central hub of protein knowledge by providing a unified view of protein sequence and functional information. Manual and automatic annotation procedures are used to add data directly to the database while extensive cross-referencing to more than 120 external databases provides access to additional relevant information in more specialized data collections. UniProtKB also integrates a range of data from other resources. All information is attributed to its original source, allowing users to trace the provenance of all data. The UniProt Consortium is committed to using and promoting common data exchange formats and technologies, and UniProtKB data is made freely available in a range of formats to facilitate integration with other databases. Database URL: http://www.uniprot.org/

Magrane, Michele; Consortium, UniProt

2011-01-01

7

The Universal Protein Resource (UniProt): an expanding universe of protein information  

Microsoft Academic Search

The Universal Protein Resource (UniProt) provides a central resource on protein sequences and functional annotation with three database components, each addressing a key need in protein bioinformatics. The UniProt Knowledgebase (UniProtKB), compris- ing the manually annotated UniProtKB\\/Swiss-Prot section and the automatically annotated UniProtKB\\/ TrEMBL section, is the preeminent storehouse of pro- tein annotation. The extensive cross-references, functional and feature annotations

Cathy H. Wu; Rolf Apweiler; Amos Bairoch; Darren A. Natale; Winona C. Barker; Brigitte Boeckmann; Serenella Ferro; Elisabeth Gasteiger; Hongzhan Huang; Rodrigo Lopez; Michele Magrane; Maria Jesus Martin; Raja Mazumder; Claire O'donovan; Nicole Redaschi; Baris E. Suzek

2006-01-01

8

SSMap: A new UniProt-PDB mapping resource for the curation of structural-related information in the UniProt/Swiss-Prot Knowledgebase  

PubMed Central

Background Sequences and structures provide valuable complementary information on protein features and functions. However, it is not always straightforward for users to gather information concurrently from the sequence and structure levels. The UniProt knowledgebase (UniProtKB) strives to help users on this undertaking by providing complete cross-references to Protein Data Bank (PDB) as well as coherent feature annotation using available structural information. In this study, SSMap a new UniProt-PDB residue-residue level mapping was generated. The primary objective of this mapping is not only to facilitate the two tasks mentioned above, but also to palliate a number of shortcomings of existent mappings. SSMap is the first isoform sequence-specific mapping resource and is up-to-date for UniProtKB annotation tasks. The method employed by SSMap differs from the other mapping resources in that it stresses on the correct reconstruction of the PDB sequence from structures, and on the correct attribution of a UniProtKB entry to each PDB chain by using a series of post-processing steps. Results SSMap was compared to other existing mapping resources in terms of the correctness of the attribution of PDB chains to UniProtKB entries, and of the quality of the pairwise alignments supporting the residue-residue mapping. It was found that SSMap shared about 80% of the mappings with other mapping sources. New and alternative mappings proposed by SSMap were mostly good as assessed by manual verification of data subsets. As for local pairwise alignments, it was shown that major discrepancies (both in terms of alignment lengths and boundaries), when present, were often due to differences in methodologies used for the mappings. Conclusion SSMap provides an independent, good quality UniProt-PDB mapping. The systematic comparison conducted in this study allows the further identification of general problems in UniProt-PDB mappings so that both the coverage and the quality of the mappings can be systematically improved for the benefit of the scientific community. SSMap mapping is currently used to provide PDB cross-references in UniProtKB.

David, Fabrice PA; Yip, Yum L

2008-01-01

9

The UniProt-GO Annotation database in 2011  

PubMed Central

The GO annotation dataset provided by the UniProt Consortium (GOA: http://www.ebi.ac.uk/GOA) is a comprehensive set of evidenced-based associations between terms from the Gene Ontology resource and UniProtKB proteins. Currently supplying over 100 million annotations to 11 million proteins in more than 360?000 taxa, this resource has increased 2-fold over the last 2?years and has benefited from a wealth of checks to improve annotation correctness and consistency as well as now supplying a greater information content enabled by GO Consortium annotation format developments. Detailed, manual GO annotations obtained from the curation of peer-reviewed papers are directly contributed by all UniProt curators and supplemented with manual and electronic annotations from 36 model organism and domain-focused scientific resources. The inclusion of high-quality, automatic annotation predictions ensures the UniProt GO annotation dataset supplies functional information to a wide range of proteins, including those from poorly characterized, non-model organism species. UniProt GO annotations are freely available in a range of formats accessible by both file downloads and web-based views. In addition, the introduction of a new, normalized file format in 2010 has made for easier handling of the complete UniProt-GOA data set.

Dimmer, Emily C.; Huntley, Rachael P.; Alam-Faruque, Yasmin; Sawford, Tony; O'Donovan, Claire; Martin, Maria J.; Bely, Benoit; Browne, Paul; Mun Chan, Wei; Eberhardt, Ruth; Gardner, Michael; Laiho, Kati; Legge, Duncan; Magrane, Michele; Pichler, Klemens; Poggioli, Diego; Sehra, Harminder; Auchincloss, Andrea; Axelsen, Kristian; Blatter, Marie-Claude; Boutet, Emmanuel; Braconi-Quintaje, Silvia; Breuza, Lionel; Bridge, Alan; Coudert, Elizabeth; Estreicher, Anne; Famiglietti, Livia; Ferro-Rojas, Serenella; Feuermann, Marc; Gos, Arnaud; Gruaz-Gumowski, Nadine; Hinz, Ursula; Hulo, Chantal; James, Janet; Jimenez, Silvia; Jungo, Florence; Keller, Guillaume; Lemercier, Phillippe; Lieberherr, Damien; Masson, Patrick; Moinat, Madelaine; Pedruzzi, Ivo; Poux, Sylvain; Rivoire, Catherine; Roechert, Bernd; Schneider, Michael; Stutz, Andre; Sundaram, Shyamala; Tognolli, Michael; Bougueleret, Lydie; Argoud-Puy, Ghislaine; Cusin, Isabelle; Duek- Roggli, Paula; Xenarios, Ioannis; Apweiler, Rolf

2012-01-01

10

Update on activities at the Universal Protein Resource (UniProt) in 2013  

PubMed Central

The mission of the Universal Protein Resource (UniProt) (http://www.uniprot.org) is to support biological research by providing a freely accessible, stable, comprehensive, fully classified, richly and accurately annotated protein sequence knowledgebase. It integrates, interprets and standardizes data from numerous resources to achieve the most comprehensive catalogue of protein sequences and functional annotation. UniProt comprises four major components, each optimized for different uses, the UniProt Archive, the UniProt Knowledgebase, the UniProt Reference Clusters and the UniProt Metagenomic and Environmental Sequence Database. UniProt is produced by the UniProt Consortium, which consists of groups from the European Bioinformatics Institute (EBI), the SIB Swiss Institute of Bioinformatics (SIB) and the Protein Information Resource (PIR). UniProt is updated and distributed every 4 weeks and can be accessed online for searches or downloads.

2013-01-01

11

Update on activities at the Universal Protein Resource (UniProt) in 2013.  

PubMed

The mission of the Universal Protein Resource (UniProt) (http://www.uniprot.org) is to support biological research by providing a freely accessible, stable, comprehensive, fully classified, richly and accurately annotated protein sequence knowledgebase. It integrates, interprets and standardizes data from numerous resources to achieve the most comprehensive catalogue of protein sequences and functional annotation. UniProt comprises four major components, each optimized for different uses, the UniProt Archive, the UniProt Knowledgebase, the UniProt Reference Clusters and the UniProt Metagenomic and Environmental Sequence Database. UniProt is produced by the UniProt Consortium, which consists of groups from the European Bioinformatics Institute (EBI), the SIB Swiss Institute of Bioinformatics (SIB) and the Protein Information Resource (PIR). UniProt is updated and distributed every 4 weeks and can be accessed online for searches or downloads. PMID:23161681

2012-11-17

12

Genes and proteins of Escherichia coli (GenProtEc).  

PubMed

GenProtEc is a database of Escherichia coli genes and their gene products, classified by type of function and physiological role and with citations to the literature for each. Also present are data on sequence similarities among E.coli proteins with PAM values, percent identity of amino acids, length of alignment and percent aligned. The database is available as a PKZip file by ftp from mbl.edu/pub/ecoli.exe. The program runs under MS-DOS on IMB-compatible machines. GenProtEc can also be accessed through the World Wide Web at URL http://mbl.edu/html/ecoli.html. PMID:8594596

Riley, M; Space, D B

1996-01-01

13

Reorganizing the protein space at the Universal Protein Resource (UniProt)  

PubMed Central

The mission of UniProt is to support biological research by providing a freely accessible, stable, comprehensive, fully classified, richly and accurately annotated protein sequence knowledgebase, with extensive cross-references and querying interfaces. UniProt is comprised of four major components, each optimized for different uses: the UniProt Archive, the UniProt Knowledgebase, the UniProt Reference Clusters and the UniProt Metagenomic and Environmental Sequence Database. A key development at UniProt is the provision of complete, reference and representative proteomes. UniProt is updated and distributed every 4 weeks and can be accessed online for searches or download at http://www.uniprot.org.

2012-01-01

14

Automated annotation of microbial proteomes in SWISS-PROT  

Microsoft Academic Search

Large-scale sequencing of prokaryotic genomes demands the automation of certain annotation tasks currently manually performed in the production of the SWISS-PROT protein knowledgebase. The HAMAP project, or 'High-quality Automated and Manual Annotation of microbial Proteomes', aims to integrate manual and automatic annotation methods in order to enhance the speed of the curation process while preserving the quality of the database

Alexandre Gattiker; Karine Michoud; Catherine Rivoire; Andrea H. Auchincloss; Elisabeth Coudert; Tania Lima; Paul Kersey; Marco Pagni; Christian J. A. Sigrist; Corinne Lachaize; Anne-lise Veuthey; Elisabeth Gasteiger; Amos Bairoch

2003-01-01

15

DetoxiProt: an integrated database for detoxification proteins  

PubMed Central

Background Detoxification proteins are a class of proteins for degradation and/or elimination of endogenous and exogenous toxins or medicines, as well as reactive oxygen species (ROS) produced by these materials. Most of these proteins are generated as a response to the stimulation of toxins or medicines. They are essential for the clearance of harmful substances and for maintenance of physiological balance in organisms. Thus, it is important to collect and integrate information on detoxification proteins. Results To store, retrieve and analyze the information related to their features and functions, we developed the DetoxiProt, a comprehensive database for annotation of these proteins. This database provides detailed introductions about different classes of the detoxification proteins. Extensive annotations of these proteins, including sequences, structures, features, inducers, inhibitors, substrates, chromosomal location, functional domains as well as physiological-biochemical properties were generated. Furthermore, pre-computed BLAST results, multiple sequence alignments and evolutionary trees for detoxification proteins are also provided for evolutionary study of conserved function and pathways. The current version of DetoxiProt contains 5956 protein entries distributed in 628 organisms. An easy to use web interface was designed, so that annotations about each detoxification protein can be retrieved by browsing with a specific method or by searching with different criteria. Conclusions DetoxiProt provides an effective and efficient way of accessing the detoxification protein sequences and other high-quality information. This database would be a valuable source for toxicologists, pharmacologists and medicinal chemists. DetoxiProt database is freely available at http://lifecenter.sgst.cn/detoxiprot/.

2011-01-01

16

The Universal Protein Resource (UniProt): an expanding universe of protein information.  

PubMed

The Universal Protein Resource (UniProt) provides a central resource on protein sequences and functional annotation with three database components, each addressing a key need in protein bioinformatics. The UniProt Knowledgebase (UniProtKB), comprising the manually annotated UniProtKB/Swiss-Prot section and the automatically annotated UniProtKB/TrEMBL section, is the preeminent storehouse of protein annotation. The extensive cross-references, functional and feature annotations and literature-based evidence attribution enable scientists to analyse proteins and query across databases. The UniProt Reference Clusters (UniRef) speed similarity searches via sequence space compression by merging sequences that are 100% (UniRef100), 90% (UniRef90) or 50% (UniRef50) identical. Finally, the UniProt Archive (UniParc) stores all publicly available protein sequences, containing the history of sequence data with links to the source databases. UniProt databases continue to grow in size and in availability of information. Recent and upcoming changes to database contents, formats, controlled vocabularies and services are described. New download availability includes all major releases of UniProtKB, sequence collections by taxonomic division and complete proteomes. A bibliography mapping service has been added, and an ID mapping service will be available soon. UniProt databases can be accessed online at http://www.uniprot.org or downloaded at ftp://ftp.uniprot.org/pub/databases/. PMID:16381842

Wu, Cathy H; Apweiler, Rolf; Bairoch, Amos; Natale, Darren A; Barker, Winona C; Boeckmann, Brigitte; Ferro, Serenella; Gasteiger, Elisabeth; Huang, Hongzhan; Lopez, Rodrigo; Magrane, Michele; Martin, Maria J; Mazumder, Raja; O'Donovan, Claire; Redaschi, Nicole; Suzek, Baris

2006-01-01

17

48 CFR 3052.219-71 - DHS mentor-protégé program.  

Code of Federal Regulations, 2011 CFR

...program for the purpose of providing developmental assistance to eligible small business...prime contractors capable of providing developmental assistance; (2) Protégé...the program means providing business developmental assistance to aid Protégés in...

2011-10-01

18

48 CFR 1019.202-70 - The Treasury Mentor Protégé Program.  

Code of Federal Regulations, 2012 CFR

...contractual actions to encourage subcontracting opportunities consistent with the efficient...increase contracting and subcontracting opportunities for the protégé firm; (5) A description...evaluation of the protégés developmental success; (6) A listing of the types...

2012-10-01

19

48 CFR 819.7107 - Selection of Protégé firms.  

Code of Federal Regulations, 2012 CFR

...firms. (a) Mentor firms will be solely responsible for selecting protégé firms. Mentors are encouraged to select from a broad base of SDVOSB or VOSB firms whose core competencies support VA's mission; and choose SDVOSB and/or VOSB protégés...

2012-10-01

20

48 CFR 852.219-72 - Evaluation factor for participation in the VA mentor-protégé program.  

Code of Federal Regulations, 2012 CFR

...for participation in the VA mentor-prot...System DEPARTMENT OF VETERANS AFFAIRS CLAUSES AND FORMS...CONTRACT CLAUSES Texts of Provisions and Clauses...for participation in the VA mentor-protégé...Mentor-Protégé Agreement. (End of clause)...

2012-10-01

21

48 CFR 852.219-72 - Evaluation factor for participation in the VA mentor-protégé program.  

Code of Federal Regulations, 2011 CFR

...for participation in the VA mentor-prot...System DEPARTMENT OF VETERANS AFFAIRS CLAUSES AND FORMS...CONTRACT CLAUSES Texts of Provisions and Clauses...for participation in the VA mentor-protégé...Mentor-Protégé Agreement. (End of Clause)...

2011-10-01

22

48 CFR 619.202-70 - The Department of State Mentor-Protégé Program.  

Code of Federal Regulations, 2012 CFR

...designed to enhance the business success of the protégé. Protégé...to encourage subcontracting opportunities for small businesses consistent...f) Measurement of program success. The success of the DOS Mentor-Protégé...that offer subcontracting opportunities. (2) The...

2012-10-01

23

Mapping proteins to disease terminologies: from UniProt to MeSH  

PubMed Central

Background Although the UniProt KnowledgeBase is not a medical-oriented database, it contains information on more than 2,000 human proteins involved in pathologies. However, these annotations are not standardized, which impairs the interoperability between biological and clinical resources. In order to make these data easily accessible to clinical researchers, we have developed a procedure to link diseases described in the UniProtKB/Swiss-Prot entries to the MeSH disease terminology. Results We mapped disease names extracted either from the UniProtKB/Swiss-Prot entry comment lines or from the corresponding OMIM entry to the MeSH. Different methods were assessed on a benchmark set of 200 disease names manually mapped to MeSH terms. The performance of the retained procedure in term of precision and recall was 86% and 64% respectively. Using the same procedure, more than 3,000 disease names in Swiss-Prot were mapped to MeSH with comparable efficiency. Conclusions This study is a first attempt to link proteins in UniProtKB to the medical resources. The indexing we provided will help clinicians and researchers navigate from diseases to genes and from genes to diseases in an efficient way. The mapping is available at: .

Mottaz, Anais; Yip, Yum L; Ruch, Patrick; Veuthey, Anne-Lise

2008-01-01

24

48 CFR 719.273-5 - Selection of Protégé firms.  

Code of Federal Regulations, 2012 CFR

...Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The U.S. Agency for International Development (USAID) Mentor-Prot...from a broad base of small business including small...

2012-10-01

25

48 CFR 752.219-70 - USAID Mentor-Protégé Program.  

Code of Federal Regulations, 2012 CFR

...System AGENCY FOR INTERNATIONAL DEVELOPMENT CLAUSES...a) Large and small business are encouraged to participate...provide eligible small business Protégés with developmental...assistance to enhance their business capabilities and...

2012-10-01

26

48 CFR 719.273-9 - Obligations under the Mentor-Protégé Program.  

Code of Federal Regulations, 2012 CFR

...Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT SOCIOECONOMIC PROGRAMS SMALL BUSINESS PROGRAMS The U.S. Agency for International Development (USAID) Mentor-Prot...of Small and Disadvantaged Business Utilization (OSDBU)...

2012-10-01

27

Genes and proteins of Escherichia coli K-12 (GenProtEC).  

PubMed

GenProtEC is a database of Escherichia coli genes and their gene products, classified by type of function and physiological role and with citations to the literature for each. Also present are data on sequence similarities amongE.coliproteins with PAM values, percent identity of amino acids, length of alignment and percent aligned. GenProtEC can also be accessed through the World Wide Web at URL http://mbl.edu/html/ecoli.html . PMID:9016503

Riley, M

1997-01-01

28

UniProtKB amid the turmoil of plant proteomics research  

PubMed Central

The UniProt KnowledgeBase (UniProtKB) provides a single, centralized, authoritative resource for protein sequences and functional information. The majority of its records is based on automatic translation of coding sequences (CDS) provided by submitters at the time of initial deposition to the nucleotide sequence databases (INSDC). This article will give a general overview of the current situation, with some specific illustrations extracted from our annotation of Arabidopsis and rice proteomes. More and more frequently, only the raw sequence of a complete genome is deposited to the nucleotide sequence databases and the gene model predictions and annotations are kept in separate, specialized model organism databases (MODs). In order to be able to provide the complete proteome of model organisms, UniProtKB had to implement pipelines for import of protein sequences from Ensembl and EnsemblGenomes. A single genome can be the target of several unrelated sequencing projects and the final assembly and gene model predictions may diverge quite significantly. In addition, several cultivars of the same species are often sequenced 1001 Arabidopsis cultivars are currently under way and the resulting proteomes are far from being identical. Therefore, one challenge for UniProtKB is to store and organize these data in a convenient way and to clearly defined reference proteomes that should be made available to users. Manual annotation is one of the landmarks of the Swiss-Prot section of UniProtKB. Besides adding functional annotation, curators are checking, and often correcting, gene model predictions. For plants, this task is limited to Arabidopsis thaliana and Oryza sativa subsp. japonica. Proteomics data providing experimental evidences confirming the existence of proteins or identifying sequence features such as post-translational modifications are also imported into UniProtKB records and the knowledgebase is cross-referenced to numerous proteomics resource.

Schneider, Michel; Consortium, the UniProt; Poux, Sylvain

2012-01-01

29

48 CFR 352.219-70 - Mentor-protégé program.  

Code of Federal Regulations, 2012 CFR

...to a mentor firm for protégé firm developmental assistance costs shall be calculated...agreeing on the dollar value of the developmental assistance the mentor firm provided...firm and provision of $5,000 of developmental assistance as $15,000 of...

2012-10-01

30

48 CFR 352.219-70 - Mentor-protégé program.  

Code of Federal Regulations, 2011 CFR

...to a mentor firm for protégé firm developmental assistance costs shall be calculated...agreeing on the dollar value of the developmental assistance the mentor firm provided...firm and provision of $5,000 of developmental assistance as $15,000 of...

2011-10-01

31

ProGlycProt: a repository of experimentally characterized prokaryotic glycoproteins  

PubMed Central

ProGlycProt (http://www.proglycprot.org/) is an open access, manually curated, comprehensive repository of bacterial and archaeal glycoproteins with at least one experimentally validated glycosite (glycosylated residue). To facilitate maximum information at one point, the database is arranged under two sections: (i) ProCGPthe main data section consisting of 95 entries with experimentally characterized glycosites and (ii) ProUGPa supplementary data section containing 245 entries with experimentally identified glycosylation but uncharacterized glycosites. Every entry in the database is fully cross-referenced and enriched with available published information about source organism, coding gene, protein, glycosites, glycosylation type, attached glycan, associated oligosaccharyl/glycosyl transferases (OSTs/GTs), supporting references, and applicable additional information. Interestingly, ProGlycProt contains as many as 174 entries for which information is unavailable or the characterized glycosites are unannotated in Swiss-Prot release 2011_07. The website supports a dedicated structure gallery of homology models and crystal structures of characterized glycoproteins in addition to two new tools developed in view of emerging information about prokaryotic sequons (conserved sequences of amino acids around glycosites) that are never or rarely seen in eukaryotic glycoproteins. ProGlycProt provides an extensive compilation of experimentally identified glycosites (334) and glycoproteins (340) of prokaryotes that could serve as an information resource for research and technology applications in glycobiology.

Bhat, Aadil H.; Mondal, Homchoru; Chauhan, Jagat S.; Raghava, Gajendra P. S.; Methi, Amrish; Rao, Alka

2012-01-01

32

49 CFR Appendix D to Part 26 - Mentor-Protégé Program Guidelines  

Code of Federal Regulations, 2011 CFR

...Guidelines D Appendix D to Part 26 Transportation...PARTICIPATION BY DISADVANTAGED BUSINESS ENTERPRISES IN DEPARTMENT...App. D Appendix D to Part 26Mentor-Protégé...must be independent business entities which meet...the recipient chooses to recognize...

2011-10-01

33

Infrastructure for the life sciences: design and implementation of the UniProt website  

PubMed Central

Background The UniProt consortium was formed in 2002 by groups from the Swiss Institute of Bioinformatics (SIB), the European Bioinformatics Institute (EBI) and the Protein Information Resource (PIR) at Georgetown University, and soon afterwards the website was set up as a central entry point to UniProt resources. Requests to this address were redirected to one of the three organisations' websites. While these sites shared a set of static pages with general information about UniProt, their pages for searching and viewing data were different. To provide users with a consistent view and to cut the cost of maintaining three separate sites, the consortium decided to develop a common website for UniProt. Following several years of intense development and a year of public beta testing, the domain was switched to the newly developed site described in this paper in July 2008. Description The UniProt consortium is the main provider of protein sequence and annotation data for much of the life sciences community. The website is the primary access point to this data and to documentation and basic tools for the data. These tools include full text and field-based text search, similarity search, multiple sequence alignment, batch retrieval and database identifier mapping. This paper discusses the design and implementation of the new website, which was released in July 2008, and shows how it improves data access for users with different levels of experience, as well as to machines for programmatic access. is open for both academic and commercial use. The site was built with open source tools and libraries. Feedback is very welcome and should be sent to help@uniprot.org. Conclusion The new UniProt website makes accessing and understanding UniProt easier than ever. The two main lessons learned are that getting the basics right for such a data provider website has huge benefits, but is not trivial and easy to underestimate, and that there is no substitute for using empirical data throughout the development process to decide on what is and what is not working for your users.

Jain, Eric; Bairoch, Amos; Duvaud, Severine; Phan, Isabelle; Redaschi, Nicole; Suzek, Baris E; Martin, Maria J; McGarvey, Peter; Gasteiger, Elisabeth

2009-01-01

34

MultiProtIdent: Identifying Proteins Using Database Search and Protein?Protein Interactions  

Microsoft Academic Search

Protein identification is important in proteomics. Proteomic analyses based on mass spectra (MS) constitute innovative ways to identify the components of protein complexes. Instruments can obtain the mass spectrum to an accuracy of 0.01 Da or better, but identification errors are inevitable. This study shows a novel tool, MultiProtIdent, which can identify proteins using additional information about protein-protein interactions and

Hsien-Da Huang; Tzong-Yi Lee; Li-Cheng Wu; Feng-Mao Lin; Hsueh-Fen Juan; Jorng-Tzong Horng; Ann-Ping Tsou

2005-01-01

35

Genes and proteins of Escherichia coli K-12 (GenProtEC)  

Microsoft Academic Search

GenProtEC is a database of Escherichia coli genes and their gene products, classified by type of function and physiological role and with citations to the literature for each. Also p resent a re d ata on sequence s imilarities among E.coli proteins, r epresenting g roups o f p ara- logous genes, w ith P AM v alues, p ercent

Monica Riley

1997-01-01

36

GPS-Prot: A web-based visualization platform for integrating host-pathogen interaction data  

PubMed Central

Background The increasing availability of HIV-host interaction datasets, including both physical and genetic interactions, has created a need for software tools to integrate and visualize the data. Because these host-pathogen interactions are extensive and interactions between human proteins are found within many different databases, it is difficult to generate integrated HIV-human interaction networks. Results We have developed a web-based platform, termed GPS-Prot http://www.gpsprot.org, that allows for facile integration of different HIV interaction data types as well as inclusion of interactions between human proteins derived from publicly-available databases, including MINT, BioGRID and HPRD. The software has the ability to group proteins into functional modules or protein complexes, generating more intuitive network representations and also allows for the uploading of user-generated data. Conclusions GPS-Prot is a software tool that allows users to easily create comprehensive and integrated HIV-host networks. A major advantage of this platform compared to other visualization tools is its web-based format, which requires no software installation or data downloads. GPS-Prot allows novice users to quickly generate networks that combine both genetic and protein-protein interactions between HIV and its human host into a single representation. Ultimately, the platform is extendable to other host-pathogen systems.

2011-01-01

37

The Significance of the ProtDeform Score for Structure Prediction and Alignment  

PubMed Central

Background When a researcher uses a program to align two proteins and gets a score, one of her main concerns is how often the program gives a similar score to pairs that are or are not in the same fold. This issue was analysed in detail recently for the program TM-align with its associated TM-score. It was shown that because the TM-score is length independent, it allows a P-value and a hit probability to be defined depending only on the score. Also, it was found that the TM-scores of gapless alignments closely follow an Extreme Value Distribution (EVD). The program ProtDeform for structural protein alignment was developed recently and is characterised by the ability to propose different transformations of different protein regions. Our goal is to analyse its associated score to allow a researcher to have objective reasons to prefer one aligner over another, and carry out a better interpretation of the output. Results The study on the ProtDeform score reveals that it is length independent in a wider score range than TM-scores and that PD-scores of gapless (random) alignments also approximately follow an EVD. On the CASP8 predictions, PD-scores and TM-scores, with respect to native structures, are highly correlated (0.95), and show that around a fifth of the predictions have a quality as low as 99.5% of the random scores. Using the Gold Standard benchmark, ProtDeform has lower probabilities of error than TM-align both at a similar speed. The analysis is extended to homology discrimination showing that, again, ProtDeform offers higher hit probabilities than TM-align. Finally, we suggest using three different P-values according to the three different contexts: Gapless alignments, optimised alignments for fold discrimination and that for superfamily discrimination. In conclusion, PD-scores are at the very least as valuable for prediction scoring as TM-scores, and on the protein classification problem, even more reliable.

Rocha, Jairo; Alberich, Ricardo

2011-01-01

38

ProtEx(TM) technology for the generation of novel therapeutic cancer vaccines  

PubMed Central

Therapeutic vaccines present an attractive alternative to conventional treatments for cancer. However, tumors have evolved various immune evasion mechanisms to modulate innate, adaptive, and regulatory immunity for survival. Therefore, successful vaccine formulations may require a non-toxic immunomodulator or adjuvant that not only induces/stimulates innate and adaptive tumor-specific immune responses, but also overcome immune evasion mechanisms. Given the paramount role costimulation plays in modulating innate, adaptive, and regulatory immune responses, costimulatory ligands may serve as effective immunomodulating components of therapeutic cancer vaccines. Our laboratory has developed a novel technology designated as ProtEx that allows for the generation of recombinant costimulatory ligands with potent immunomodulatory activities and the display of these molecules on the cell surface in a rapid and efficient manner as a practical and safe alternative to gene therapy for immunomodulation. Importantly, the costimulatory ligands not only function when displayed on tumor cells, but also as soluble proteins that can be used as immunomodulatory components of conventional vaccine formulations containing tumor-associated antigens (TAAs). We herein discuss the application of the ProtEx technology to the development of effective cell-based as well as cell-free conventional therapeutic cancer vaccines.

Schabowsky, Rich-Henry; Sharma, Rajesh K.; Madireddi, Shravan; Srivastava, Abhishek; Yolcu, Esma S.; Shirwan, Haval

2010-01-01

39

SubCellProt: predicting protein subcellular localization using machine learning approaches.  

PubMed

High-throughput genome sequencing projects continue to churn out enormous amounts of raw sequence data. However, most of this raw sequence data is unannotated and, hence, not very useful. Among the various approaches to decipher the function of a protein, one is to determine its localization. Experimental approaches for proteome annotation including determination of a protein's subcellular localizations are very costly and labor intensive. Besides the available experimental methods, in silico methods present alternative approaches to accomplish this task. Here, we present two machine learning approaches for prediction of the subcellular localization of a protein from the primary sequence information. Two machine learning algorithms, k Nearest Neighbor (k-NN) and Probabilistic Neural Network (PNN) were used to classify an unknown protein into one of the 11 subcellular localizations. The final prediction is made on the basis of a consensus of the predictions made by two algorithms and a probability is assigned to it. The results indicate that the primary sequence derived features like amino acid composition, sequence order and physicochemical properties can be used to assign subcellular localization with a fair degree of accuracy. Moreover, with the enhanced accuracy of our approach and the definition of a prediction domain, this method can be used for proteome annotation in a high throughput manner. SubCellProt is available at www.databases.niper.ac.in/SubCellProt. PMID:19537160

Garg, Prabha; Sharma, Virag; Chaudhari, Pradeep; Roy, Nilanjan

2009-01-01

40

ProtNA-ASA: Protein-nucleic acid structural database with information on accessible surface area  

NASA Astrophysics Data System (ADS)

The article describes a new database (ProtNA-ASA), which combines the data on conformational parameters of nucleic acids and calculations of the accessible surface area (ASA) of nucleic acid atoms in protein-DNA/RNA complexes. As for October 2008, the database contains 214 DNA-protein and 28 RNA-protein non-homologous complexes. The database provides structural parameters that describe local geometry of base pairs and base-pair steps as well as backbone torsion angles. Additionally, total ASA of DNA/RNA atoms and the accessible area of atoms in the minor and major grooves are calculated. ProtNA-ASA database facilitates studying the relationship between the DNA/RNA conformation and availability of atoms for contact with proteins either in major or in minor groove for different nucleotides. Such an analysis is important for understanding the principles of molecular recognition including indirect sequence readout. The database is publicly available for use at http://www.protna.bio-page.org.

Tkachenko, M. Y.; Boryskina, O. P.; Shestopalova, A. V.; Tolstorukov, M. Y.

41

SynProt: A Database for Proteins of Detergent-Resistant Synaptic Protein Preparations  

PubMed Central

Chemical synapses are highly specialized cellcell contacts for communication between neurons in the CNS characterized by complex and dynamic protein networks at both synaptic membranes. The cytomatrix at the active zone (CAZ) organizes the apparatus for the regulated release of transmitters from the presynapse. At the postsynaptic side, the postsynaptic density constitutes the machinery for detection, integration, and transduction of the transmitter signal. Both pre- and postsynaptic protein networks represent the molecular substrates for synaptic plasticity. Their function can be altered both by regulating their composition and by post-translational modification of their components. For a comprehensive understanding of synaptic networks the entire ensemble of synaptic proteins has to be considered. To support this, we established a comprehensive database for synaptic junction proteins (SynProt database) primarily based on proteomics data obtained from biochemical preparations of detergent-resistant synaptic junctions. The database currently contains 2,788 non-redundant entries of rat, mouse, and some human proteins, which mainly have been manually extracted from 12 proteomic studies and annotated for synaptic subcellular localization. Each dataset is completed with manually added information including protein classifiers as well as automatically retrieved and updated information from public databases (UniProt and PubMed). We intend that the database will be used to support modeling of synaptic protein networks and rational experimental design.

Pielot, Rainer; Smalla, Karl-Heinz; Muller, Anke; Landgraf, Peter; Lehmann, Anne-Christin; Eisenschmidt, Elke; Haus, Utz-Uwe; Weismantel, Robert; Gundelfinger, Eckart D.; Dieterich, Daniela C.

2012-01-01

42

Application of text-mining for updating protein post-translational modification annotation in UniProtKB  

PubMed Central

Background The annotation of protein post-translational modifications (PTMs) is an important task of UniProtKB curators and, with continuing improvements in experimental methodology, an ever greater number of articles are being published on this topic. To help curators cope with this growing body of information we have developed a system which extracts information from the scientific literature for the most frequently annotated PTMs in UniProtKB. Results The procedure uses a pattern-matching and rule-based approach to extract sentences with information on the type and site of modification. A ranked list of protein candidates for the modification is also provided. For PTM extraction, precision varies from 57% to 94%, and recall from 75% to 95%, according to the type of modification. The procedure was used to track new publications on PTMs and to recover potential supporting evidence for phosphorylation sites annotated based on the results of large scale proteomics experiments. Conclusions The information retrieval and extraction method we have developed in this study forms the basis of a simple tool for the manual curation of protein post-translational modifications in UniProtKB/Swiss-Prot. Our work demonstrates that even simple text-mining tools can be effectively adapted for database curation tasks, providing that a thorough understanding of the working process and requirements are first obtained. This system can be accessed at http://eagl.unige.ch/PTM/.

2013-01-01

43

Can Inferred Provenance and Its Visualisation Be Used to Detect Erroneous Annotation? A Case Study Using UniProtKB.  

PubMed

A constant influx of new data poses a challenge in keeping the annotation in biological databases current. Most biological databases contain significant quantities of textual annotation, which often contains the richest source of knowledge. Many databases reuse existing knowledge; during the curation process annotations are often propagated between entries. However, this is often not made explicit. Therefore, it can be hard, potentially impossible, for a reader to identify where an annotation originated from. Within this work we attempt to identify annotation provenance and track its subsequent propagation. Specifically, we exploit annotation reuse within the UniProt Knowledgebase (UniProtKB), at the level of individual sentences. We describe a visualisation approach for the provenance and propagation of sentences in UniProtKB which enables a large-scale statistical analysis. Initially levels of sentence reuse within UniProtKB were analysed, showing that reuse is heavily prevalent, which enables the tracking of provenance and propagation. By analysing sentences throughout UniProtKB, a number of interesting propagation patterns were identified, covering over [Formula: see text] sentences. Over [Formula: see text] sentences remain in the database after they have been removed from the entries where they originally occurred. Analysing a subset of these sentences suggest that approximately [Formula: see text] are erroneous, whilst [Formula: see text] appear to be inconsistent. These results suggest that being able to visualise sentence propagation and provenance can aid in the determination of the accuracy and quality of textual annotation. Source code and supplementary data are available from the authors website at http://homepages.cs.ncl.ac.uk/m.j.bell1/sentence_analysis/. PMID:24143170

Bell, Michael J; Collison, Matthew; Lord, Phillip

2013-10-15

44

Can Inferred Provenance and Its Visualisation Be Used to Detect Erroneous Annotation? A Case Study Using UniProtKB  

PubMed Central

A constant influx of new data poses a challenge in keeping the annotation in biological databases current. Most biological databases contain significant quantities of textual annotation, which often contains the richest source of knowledge. Many databases reuse existing knowledge; during the curation process annotations are often propagated between entries. However, this is often not made explicit. Therefore, it can be hard, potentially impossible, for a reader to identify where an annotation originated from. Within this work we attempt to identify annotation provenance and track its subsequent propagation. Specifically, we exploit annotation reuse within the UniProt Knowledgebase (UniProtKB), at the level of individual sentences. We describe a visualisation approach for the provenance and propagation of sentences in UniProtKB which enables a large-scale statistical analysis. Initially levels of sentence reuse within UniProtKB were analysed, showing that reuse is heavily prevalent, which enables the tracking of provenance and propagation. By analysing sentences throughout UniProtKB, a number of interesting propagation patterns were identified, covering over sentences. Over sentences remain in the database after they have been removed from the entries where they originally occurred. Analysing a subset of these sentences suggest that approximately are erroneous, whilst appear to be inconsistent. These results suggest that being able to visualise sentence propagation and provenance can aid in the determination of the accuracy and quality of textual annotation. Source code and supplementary data are available from the authors website at http://homepages.cs.ncl.ac.uk/m.j.bell1/sentence_analysis/.

Bell, Michael J.; Collison, Matthew; Lord, Phillip

2013-01-01

45

ProtSweep, 2Dsweep and DomainSweep: protein analysis suite at DKFZ.  

PubMed

The wealth of transcript information that has been made publicly available in recent years has led to large pools of individual web sites offering access to bioinformatics software. However, finding out which services exist, what they can or cannot do, how to use them and how to feed results from one service to the next one in the right format can be very time and resource consuming, especially for non-experts. Automating this task, we present a suite of protein annotation pipelines (tasks) developed at the German Cancer Research Centre (DKFZ) oriented to protein annotation by homology (ProtSweep), by domain analysis (DomainSweep), and by secondary structure elements (2Dsweep). The aim of these tasks is to perform an exhaustive structural and functional analysis employing a wide variety of methods in combination with the most updated public databases. The three servers are available for academic users at the HUSAR open server http://genius.embnet.dkfz-heidelberg.de/menu/biounit/open-husar/ PMID:17526514

del Val, C; Ernst, P; Falkenhahn, M; Fladerer, C; Glatting, K H; Suhai, S; Hotz-Wagenblatt, A

2007-05-25

46

48 CFR 3052.219-72 - Evaluation of prime contractor participation in the DHS mentor-protégé program.  

Code of Federal Regulations, 2011 CFR

...offeror shall provide a signed letter of mentor-protégé agreement approval from the DHS Office...before initial evaluation of proposals. The contracting officer...after initial evaluation of proposals, but before final...

2011-10-01

47

48 CFR 3052.219-72 - Evaluation of prime contractor participation in the DHS mentor-protégé program.  

Code of Federal Regulations, 2012 CFR

...offeror shall provide a signed letter of mentor-protégé agreement approval from the DHS Office...before initial evaluation of proposals. The contracting officer...after initial evaluation of proposals, but before final...

2012-10-01

48

48 CFR 719.273 - The U.S. Agency for International Development (USAID) Mentor-Protégé Program.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 false The U.S. Agency for International Development (USAID) Mentor-Prot...Acquisition Regulations System AGENCY FOR INTERNATIONAL DEVELOPMENT SOCIOECONOMIC PROGRAMS...BUSINESS PROGRAMS The U.S. Agency for International Development (USAID)...

2011-10-01

49

An approach to describing and analysing bulk biological annotation quality: a case study using UniProtKB  

PubMed Central

Motivation: Annotations are a key feature of many biological databases, used to convey our knowledge of a sequence to the reader. Ideally, annotations are curated manually, however manual curation is costly, time consuming and requires expert knowledge and training. Given these issues and the exponential increase of data, many databases implement automated annotation pipelines in an attempt to avoid un-annotated entries. Both manual and automated annotations vary in quality between databases and annotators, making assessment of annotation reliability problematic for users. The community lacks a generic measure for determining annotation quality and correctness, which we look at addressing within this article. Specifically we investigate word reuse within bulk textual annotations and relate this to Zipf's Principle of Least Effort. We use the UniProt Knowledgebase (UniProtKB) as a case study to demonstrate this approach since it allows us to compare annotation change, both over time and between automated and manually curated annotations. Results: By applying power-law distributions to word reuse in annotation, we show clear trends in UniProtKB over time, which are consistent with existing studies of quality on free text English. Further, we show a clear distinction between manual and automated analysis and investigate cohorts of protein records as they mature. These results suggest that this approach holds distinct promise as a mechanism for judging annotation quality. Availability: Source code is available at the authors website: http://homepages.cs.ncl.ac.uk/m.j.bell1/annotation. Contact: phillip.lord@newcastle.ac.uk

Bell, Michael J.; Gillespie, Colin S.; Swan, Daniel; Lord, Phillip

2012-01-01

50

GATA-3 promotes T-cell specification by repressing B-cell potential in pro-T cells in mice.  

PubMed

Transcription factors orchestrate T-lineage differentiation in the thymus. One critical checkpoint involves Notch1 signaling that instructs T-cell commitment at the expense of the B-lineage program. While GATA-3 is required for T-cell specification, its mechanism of action is poorly understood. We show that GATA-3 works in concert with Notch1 to commit thymic progenitors to the T-cell lineage via 2 distinct pathways. First, GATA-3 orchestrates a transcriptional repertoire that is required for thymocyte maturation up to and beyond the pro-T-cell stage. Second, GATA-3 critically suppresses a latent B-cell potential in proT cells. As such, GATA-3 is essential to sealing in Notch-induced T-cell fate in early thymocyte precursors by promoting T-cell identity through the repression of alternative developmental options. PMID:23287858

Garca-Ojeda, Marcos E; Klein Wolterink, Roel G J; Lematre, Fabrice; Richard-Le Goff, Odile; Hasan, Milena; Hendriks, Rudolf W; Cumano, Ana; Di Santo, James P

2013-01-03

51

Using ProtMAX to create high-mass-accuracy precursor alignments from label-free quantitative mass spectrometry data generated in shotgun proteomics experiments.  

PubMed

Recently, new software tools have been developed for improved protein quantification using mass spectrometry (MS) data. However, there are still limitations especially in high-sample-throughput quantification methods, and most of these relate to extensive computational calculations. The mass accuracy precursor alignment (MAPA) strategy has been shown to be a robust method for relative protein quantification. Its major advantages are high resolution, sensitivity and sample throughput. Its accuracy is data dependent and thus best suited for precursor mass-to-charge precision of ?1 p.p.m. This protocol describes how to use a software tool (ProtMAX) that allows for the automated alignment of precursors from up to several hundred MS runs within minutes without computational restrictions. It comprises features for 'ion intensity count' and 'target search' of a distinct set of peptides. This procedure also includes the recommended MS settings for complex quantitative MAPA analysis using ProtMAX (http://www.univie.ac.at/mosys/software.html). PMID:23449253

Egelhofer, Volker; Hoehenwarter, Wolfgang; Lyon, David; Weckwerth, Wolfram; Wienkoop, Stefanie

2013-02-28

52

LiF:Mg,Ti TLD response as a function of photon energy for moderately filtered x-ray spectra in the range of 20-250 kVp relative to {sup 60}Co  

SciTech Connect

The response of LiF:Mg,Ti thermoluminescent dosimeters (TLDs) as a function of photon energy was determined using irradiations with moderately filtered x-ray beams in the energy range of 20-250 kVp relative to the response to irradiations with {sup 60}Co photons. To determine if the relative light output from LiF:Mg,Ti TLDs per unit air kerma as a function of photon energy can be predicted using calculations such as Monte Carlo (MC) simulations, measurements from the x-ray beam irradiations were compared with MC calculated results, similar to the methodology used by Davis et al. [Radiat. Prot. Dosim. 106, 33-43 (2003)]. TLDs were irradiated in photon beams with well-known air kerma rates using the National Institute of Standards and Technology traceable M-series x-ray beams in the range of 20-250 kVp. For each x-ray beam, several sets of TLDs were irradiated for times corresponding to different air kerma levels to take into account any dose nonlinearity. TLD light output was then compared to that from several sets of TLDs irradiated at similar corresponding air kerma levels using a {sup 60}Co irradiator. The MC code MCNP5 was used to account for photon scatter and attenuation in the holder and TLDs and was used to calculate the predicted relative TLD light output per unit air kerma for irradiations with each of the experimentally used photon beams. The measured relative TLD response as a function of photon energy differed by up to 13% from the MC calculations. We conclude that MC calculations do not accurately predict the relative response of TLDs as a function of photon energy, consistent with the conclusions of Davis et al. [Radiat. Prot. Dosim. 106, 33-43 (2003)]. This is likely due to complications in the solid state physics of the thermoluminescence process that are not incorporated into the simulation.

Nunn, A. A.; Davis, S. D.; Micka, J. A.; DeWerd, L. A. [Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States) and Anchorage Radiation Therapy Center, Anchorage, Alaska 99508 (United States); Department of Medical Physics, University of Wisconsin, Madison, Wisconsin 53706 (United States)

2008-05-15

53

Evidence-based recommendations for optimal dietary protein intake in older people: a position paper from the PROT-AGE Study Group.  

PubMed

New evidence shows that older adults need more dietary protein than do younger adults to support good health, promote recovery from illness, and maintain functionality. Older people need to make up for age-related changes in protein metabolism, such as high splanchnic extraction and declining anabolic responses to ingested protein. They also need more protein to offset inflammatory and catabolic conditions associated with chronic and acute diseases that occur commonly with aging. With the goal of developing updated, evidence-based recommendations for optimal protein intake by older people, the European Union Geriatric Medicine Society (EUGMS), in cooperation with other scientific organizations, appointed an international study group to review dietary protein needs with aging (PROT-AGE Study Group). To help older people (>65 years) maintain and regain lean body mass and function, the PROT-AGE study group recommends average daily intake at least in the range of 1.0 to 1.2 g protein per kilogram of body weight per day. Both endurance- and resistance-type exercises are recommended at individualized levels that are safe and tolerated, and higher protein intake (ie, ? 1.2 g/kg body weight/d) is advised for those who are exercising and otherwise active. Most older adults who have acute or chronic diseases need even more dietary protein (ie, 1.2-1.5 g/kg body weight/d). Older people with severe kidney disease (ie, estimated GFR <30 mL/min/1.73 m(2)), but who are not on dialysis, are an exception to this rule; these individuals may need to limit protein intake. Protein quality, timing of ingestion, and intake of other nutritional supplements may be relevant, but evidence is not yet sufficient to support specific recommendations. Older people are vulnerable to losses in physical function capacity, and such losses predict loss of independence, falls, and even mortality. Thus, future studies aimed at pinpointing optimal protein intake in specific populations of older people need to include measures of physical function. PMID:23867520

Bauer, Jrgen; Biolo, Gianni; Cederholm, Tommy; Cesari, Matteo; Cruz-Jentoft, Alfonso J; Morley, John E; Phillips, Stuart; Sieber, Cornel; Stehle, Peter; Teta, Daniel; Visvanathan, Renuka; Volpi, Elena; Boirie, Yves

2013-07-16

54

Radioactivity in food and the environment: calculations of UK radiation doses using integrated methods  

Microsoft Academic Search

Dear SirI read with interest the paper by W C Camplin, G P Brownless, G D Round, K Winpenny and G J Hunt from the Centre for Environment, Fisheries and Aquaculture Science (CEFAS) on `Radioactivity in food and the environment: calculations of UK radiation doses using integrated methods' in the December 2002 issue of this journal (J. Radiol. Prot.22 371-88).

Rob Allott

2003-01-01

55

DOSim: An R package for similarity between diseases based on Disease Ontology  

Microsoft Academic Search

BackgroundThe construction of the Disease Ontology (DO) has helped promote the investigation of diseases and disease risk factors. DO\\u000a enables researchers to analyse disease similarity by adopting semantic similarity measures, and has expanded our understanding\\u000a of the relationships between different diseases and to classify them. Simultaneously, similarities between genes can also\\u000a be analysed by their associations with similar diseases. As

Jiang Li; Binsheng Gong; Xi Chen; Tao Liu; Chao Wu; Fan Zhang; Chunquan Li; Xiang Li; Shaoqi Rao; Xia Li

2011-01-01

56

Spherical polar co-ordinate calculations of induced fields in the retina and head for applied magnetic fields at 50 Hz.  

PubMed

This paper sets out to explore the effects of voxel resolution, from 2 mm down to 0.1 mm for Cartesian co-ordinates and the differences between Cartesian and spherical polar co-ordinates for a standardized test-bed model of the eye. This model was taken from the work of Yoriyaz et al (2005 Radiat. Prot. Dosim. 115 316-9) who have developed a detailed geometric description of the eye including choroid, retina, sclera, lens, cornea, anterior chamber, vitreous humour and optic nerve for ophthalmic brachytherapy. The spherical co-ordinate model has radial and angular steplengths of 0.1 mm and 0.25, respectively. The current density averaged over 1 cm(2) and the 99th percentile value of the induced electric field have been calculated in the retina and central nervous system for uniform magnetic fields. The Cartesian co-ordinate calculations proceed in a sequence of grids at 2, 1, 0.5, 0.2 and 0.1 mm resolution with the potentials from the previous calculation at a coarser grid providing the boundary conditions on the finer grid. The 0.2 mm grid provides the boundary conditions for the spherical polar calculations. Comparisons are made with the International Commission on Non-Ionizing Radiation Protection reference levels. PMID:21725142

Dimbylow, Peter

2011-07-01

57

Spherical polar co-ordinate calculations of induced fields in the retina and head for applied magnetic fields at 50 Hz  

NASA Astrophysics Data System (ADS)

This paper sets out to explore the effects of voxel resolution, from 2 mm down to 0.1 mm for Cartesian co-ordinates and the differences between Cartesian and spherical polar co-ordinates for a standardized test-bed model of the eye. This model was taken from the work of Yoriyaz et al (2005 Radiat. Prot. Dosim. 115 316-9) who have developed a detailed geometric description of the eye including choroid, retina, sclera, lens, cornea, anterior chamber, vitreous humour and optic nerve for ophthalmic brachytherapy. The spherical co-ordinate model has radial and angular steplengths of 0.1 mm and 0.25, respectively. The current density averaged over 1 cm2 and the 99th percentile value of the induced electric field have been calculated in the retina and central nervous system for uniform magnetic fields. The Cartesian co-ordinate calculations proceed in a sequence of grids at 2, 1, 0.5, 0.2 and 0.1 mm resolution with the potentials from the previous calculation at a coarser grid providing the boundary conditions on the finer grid. The 0.2 mm grid provides the boundary conditions for the spherical polar calculations. Comparisons are made with the International Commission on Non-Ionizing Radiation Protection reference levels.

Dimbylow, Peter

2011-07-01

58

Preliminary modeling of BNCT beam tube on IRT in Sofia.  

PubMed

The technical design of the research reactor IRT in Sofia is in progress. It includes an arrangement for a BNCT facility for tumor treatment. Modeling of geometry and material composition of filter/collimator for the BNCT beam tube on IRT has been carried out following the beam tube configuration of the Massachusetts Institute of Technology Reactor [Harling et al., 2002. The fission converter-based epithermal neutron irradiation facility at the Massachusetts Institute of Technology Reactor. Nucl. Sci. Eng. 140, 223-240.] and taking into account an ability to include the tube into the IRT reactor geometry. The results of neutron and gamma transport calculations performed for the model have shown that the facility will be able to supply an epithermal neutron flux of about 5 x 10(9) n cm(-2)s(-1), with low contamination from fast neutrons and gamma rays that would be among the best facilities currently available. An optimiziation study has been performed for the beam collimator, following similar studies for the TAPIRO research reactor in Italy. [Nava et al., 2005. Monte Carlo optimization of a BNCT facility for treating brain gliomas at the TAPIRO reactor. Radiat. Prot. Dosim. 116 (1-4), 475-481.]. PMID:19410473

Belousov, S; Ilieva, K

2009-04-07

59

Simulations of the MATROSHKA experiment at the international space station using PHITS.  

PubMed

Concerns about the biological effects of space radiation are increasing rapidly due to the perspective of long-duration manned missions, both in relation to the International Space Station (ISS) and to manned interplanetary missions to Moon and Mars in the future. As a preparation for these long-duration space missions, it is important to ensure an excellent capability to evaluate the impact of space radiation on human health, in order to secure the safety of the astronauts/cosmonauts and minimize their risks. It is therefore necessary to measure the radiation load on the personnel both inside and outside the space vehicles and certify that organ- and tissue-equivalent doses can be simulated as accurate as possible. In this paper, simulations are presented using the three-dimensional Monte Carlo Particle and Heavy-Ion Transport code System (PHITS) (Iwase et al. in J Nucl Sci Tech 39(11):1142-1151, 2002) of long-term dose measurements performed with the European Space Agency-supported MATROSHKA (MTR) experiment (Reitz and Berger in Radiat Prot Dosim 120:442-445, 2006). MATROSHKA is an anthropomorphic phantom containing over 6,000 radiation detectors, mimicking a human head and torso. The MTR experiment, led by the German Aerospace Center (DLR), was launched in January 2004 and has measured the absorbed doses from space radiation both inside and outside the ISS. Comparisons of simulations with measurements outside the ISS are presented. The results indicate that PHITS is a suitable tool for estimation of doses received from cosmic radiation and for study of the shielding of spacecraft against cosmic radiation. PMID:20496176

Sihver, L; Sato, T; Puchalska, M; Reitz, G

2010-05-25

60

Radiation Biochemistry.  

National Technical Information Service (NTIS)

Contents: physical characteristics of ionizing radiation and its interaction with matter; effect of ionizing radiation on water; formation of peroxides by ionizing radiation; effects of ionizing radiation on simple proteins and their decomposi tion produc...

A. M. Kuzin

1964-01-01

61

Radiation enteritis  

MedlinePLUS

Radiation enteropathy; Radiation-induced small bowel injury; Post-radiation enteritis ... Radiation therapy uses high-powered x-rays, particles, or radioactive seeds to kill cancer cells. Along with ...

62

Radiation Therapy  

MedlinePLUS

... how to cope with side effects. What Is Radiation Therapy? Cancer is a disease that causes cells ... when they're giving radiation treatments. How Is Radiation Given? Doctors can give people with cancer radiation ...

63

Radiation Therapy  

MedlinePLUS

... person can start feeling well again. How Is Radiation Given? Cancer can be treated with radiation therapy ... of cancer kids get. Continue What Happens During Radiation Therapy? Because the radiation treatment needs to be ...

64

Radiation dosimetry  

Microsoft Academic Search

This article summarized the basic facts about the measurement of ionizing radiation, usually referred to as radiation dosimetry. The article defines the common radiation quantities and units; gives typical levels of natural radiation and medical exposures; and describes the most important biological effects of radiation and the methods used to measure radiation. Finally, a proposal is made for a new

1991-01-01

65

Professions in Radiation Therapy  

MedlinePLUS

Professions in: Radiation Therapy Radiation Oncologist Medical Radiation Physicist Radiation Therapist Dosimetrist Radiation Oncology Nurse Social Worker Dietitian Radiation Oncologist Radiation oncologists ...

66

Response of LiF:Mg,Ti thermoluminescent dosimeters at photon energies relevant to the dosimetry of brachytherapy (<1 MeV)  

SciTech Connect

Purpose: High energy photon beams are used in calibrating dosimeters for use in brachytherapy since absorbed dose to water can be determined accurately and with traceability to primary standards in such beams, using calibrated ion chambers and standard dosimetry protocols. For use in brachytherapy, beam quality correction factors are needed, which include corrections for differences in mass energy absorption properties between water and detector as well as variations in detector response (intrinsic efficiency) with radiation quality, caused by variations in the density of ionization (linear energy transfer (LET) -distributions) along the secondary electron tracks. The aim of this work was to investigate experimentally the detector response of LiF:Mg,Ti thermoluminescent dosimeters (TLD) for photon energies below 1 MeV relative to {sup 60}Co and to address discrepancies between the results found in recent publications of detector response. Methods: LiF:Mg,Ti dosimeters of formulation MTS-N Poland were irradiated to known values of air kerma free-in-air in x-ray beams at tube voltages 25-250 kV, in {sup 137}Cs- and {sup 60}Co-beams at the Swedish Secondary Standards Dosimetry Laboratory. Conversions from air kerma free-in-air into values of mean absorbed dose in the dosimeters in the actual irradiation geometries were made using EGSnrc Monte Carlo simulations. X-ray energy spectra were measured or calculated for the actual beams. Detector response relative to that for {sup 60}Co was determined at each beam quality. Results: An increase in relative response was seen for all beam qualities ranging from 8% at tube voltage 25 kV (effective energy 13 keV) to 3%-4% at 250 kV (122 keV effective energy) and {sup 137}Cs with a minimum at 80 keV effective energy (tube voltage 180 kV). The variation with effective energy was similar to that reported by Davis et al.[Radiat. Prot. Dosim. 106, 33-43 (2003)] with our values being systematically lower by 2%-4%. Compared to the results by Nunn et al.[Med. Phys. 35, 1861-1869 (2008)], the relative detector response as a function of effective energy differed in both shape and magnitude. This could be explained by the higher maximum read-out temperature (350 deg. C) used by Nunn et al.[Med. Phys. 35, 1861-1869 (2008)], allowing light emitted from high-temperature peaks with a strong LET dependence to be registered. Use of TLD-100 by Davis et al.[Radiat. Prot. Dosim. 106, 33-43 (2003)] with a stronger super-linear dose response compared to MTS-N was identified as causing the lower relative detector response in this work. Conclusions: Both careful dosimetry and strict protocols for handling the TLDs are required to reach solid experimental data on relative detector response. This work confirms older findings that an over-response relative to {sup 60}Co exists for photon energies below 200-300 keV. Comparison with the results from the literature indicates that using similar protocols for annealing and read-out, dosimeters of different makes (TLD-100, MTS-N) differ in relative detector response. Though universality of the results has not been proven and further investigation is needed, it is anticipated that with the use of strict protocols for annealing and read-out, it will be possible to determine correction factors that can be used to reduce uncertainties in dose measurements around brachytherapy sources at photon energies where primary standards for absorbed dose to water are not available.

Tedgren, Aasa Carlsson; Hedman, Angelica; Grindborg, Jan-Erik; Carlsson, Gudrun Alm [Radiation Physics, Department of Medical and Health Sciences (IMH), Faculty of Health Sciences, Linkoeping University, SE 581 85 Linkoeping, Sweden and Swedish Radiation Safety Authority, SE 171 16 Stockholm (Sweden); Radiation Physics, Department of Medical and Health Sciences (IMH), Faculty of Health Sciences, Linkoeping University, SE 581 85 Linkoeping, Sweden and Department of Radiation Physics UHL, County Council of Oestergoetland, SE 581 85 Linkoeping (Sweden); Swedish Radiation Safety Authority, SE 171 16 Stockholm (Sweden); Radiation Physics, Department of Medical and Health Sciences (IMH), Faculty of Health Sciences, Linkoeping University, SE 581 85 Linkoeping (Sweden)

2011-10-15

67

Radiation Therapy  

MedlinePLUS

... weeks. New Techniques Newer radiation techniques such as proton beam radiotherapy, which uses a different form of ... requiring many more beams than conventional radiation therapy. Proton Beam Therapy compared to traditional photon beam radiation, ...

68

Radiation Therapy  

MedlinePLUS

Radiation therapy is a cancer treatment. It uses high doses of radiation to kill cancer cells and stop them from ... half of all cancer patients receive it. The radiation may be external, from special machines, or internal, ...

69

UV Radiation  

MedlinePLUS

... you see, infrared radiation that you feel as heat, and ultraviolet (UV) radiation that you cant see or feel. UV radiation has a shorter wavelength and higher energy than visible light. It affects human health both ...

70

Atmospheric radiation  

SciTech Connect

Studies of atmospheric radiative processes are summarized for the period 1987-1990. Topics discussed include radiation modeling; clouds and radiation; radiative effects in dynamics and climate; radiation budget and aerosol effects; and gaseous absorption, particulate scattering and surface reflection. It is concluded that the key developments of the period are a defining of the radiative forcing to the climate system by trace gases and clouds, the recognition that cloud microphysics and morphology need to be incorporated not only into radiation models but also climate models, and the isolation of a few important unsolved theoretical problems in atmospheric radiation.

Harshvardhan, M.R. (USAF, Geophysics Laboratory, Hanscom AFB, MA (United States))

1991-01-01

71

Radiation Laws  

NSDL National Science Digital Library

This site lists physical laws that describe radiation. Topics covered include the Plank Radiation Law, and the Wien and Stefan-Boltzmann Laws. The site also features a table summarizing the blackbody temperatures necessary to give a peak for emitted radiation in various regions of the spectrum, and three Java applets illustrating important properties of blackbody radiation.

Astronomy, Department O.; Knoxville, University O.

72

Radiation Enterocolitis  

Microsoft Academic Search

\\u000a This chapter is focused on review of the diagnostic tests and management of radiation enterocolitis. Radiation enterocolitis\\u000a can occur after radiation therapy for urological, gynecological, and gastrointestinal cancer. Diarrhea, which is often a dominant\\u000a symptom, can develop from a few weeks to many years after radiation treatment depending on the severity and the extent of\\u000a the injury. Radiation enterocolitis can

Einar G. Lurix; Jorge A. Zapatier; Andrew Ukleja

73

Fabric radiators  

NASA Astrophysics Data System (ADS)

The design of large, high-temperature space radiators is still an evolving discipline. Researchers expanded the data base available to a designer by studying a novel class of radiators constructed of ceramic fabrics and/or composite materials. It appears that fabric radiators have features not available in more conventional radiator types, while offering the light weight and stowability of advanced radiators such as liquid droplet types. Experiments show that fabrics can be treated to become impermeable to the working fluid while retaining flexibility. This feature of fabrics, when allied to their low density, provides a material well-adapted to radiator construction.

Antoniak, Zenen I.; Jacox, Michael G.

74

Radiation Monitoring.  

National Technical Information Service (NTIS)

This general discussion of radiation and radioactivity as they relate to mines, particularly uranium mines, includes the following topics: general radiation discussion; radioactive minerals and related health hazards in mining; lung cancer among uranium a...

1979-01-01

75

Radiation Therapy  

MedlinePLUS

... rays, but the power can also come from protons or other types of energy. The term "radiation ... Why it's done Mayo Clinic products and services Proton beam therapy at Mayo Clinic Radiation therapy at ...

76

Radiation Carcinogenesis.  

National Technical Information Service (NTIS)

The risk of iatrogenic tumors with radiation therapy is so outweighed by the benefit of cure that estimates of risk have not been considered necessary. However, with the introduction of chemotherapy, combined therapy, and particle radiation therapy, the c...

R. J. M. Fry

1976-01-01

77

Radiation Cataract  

NASA Astrophysics Data System (ADS)

These studies provide an opportunity to study the effects of low-dose radiation exposure and the influence(s) of genetic radiosensitivity in a rodent model that has great relevance and similarity to human response to radiation exposure and determination of appropriate human exposure guidelines. Futhermore, any extension of the presumed radiation cataract threshold in this animal model to lower doses is likely to be important to the development of appropriate guidelines for national space radiation risk policy.

Kleiman, Norman; Hall, Eric; Brenner, David; Lieberman, Howard; Smilenov, Lubomir

78

Radiation Exposure  

MedlinePLUS

Radiation is energy that travels in the form of waves or high-speed particles. It occurs naturally in sunlight. Man-made radiation is used in X-rays, nuclear weapons, nuclear power plants and cancer treatment. If you are exposed to small amounts of radiation over a long time, it raises ...

79

Radiation receiver  

Microsoft Academic Search

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said

Hunt; Arlon J

1983-01-01

80

(Radiation protection)  

Microsoft Academic Search

The traveler attended the Seventh Congress of the International Radiation Protection Association (IRPA) in Sydney, Australia, April 11--15, 1988. This conference consisted of a comprehensive technical program with oral and poster presentations in all areas of radiation protection including several topics which were of special interest to the traveler; e.g., neutron dosimetry, personnel dosimetry and instrumentation, radiobiology, and radiation accidents.

Swaja

1988-01-01

81

Recent Developments of the Local Effect Model (LEM) - Implications of clustered damage on cell transformation  

NASA Astrophysics Data System (ADS)

Exposure to radiation of high-energy and highly charged ions (HZE) causes a major risk to human beings, since in long term space explorations about 10 protons per month and about one HZE particle per month hit each cell nucleus (1). Despite the larger number of light ions, the high ionisation power of HZE particles and its corresponding more complex damage represents a major hazard for astronauts. Therefore, in order to get a reasonable risk estimate, it is necessary to take into account the entire mixed radiation field. Frequently, neoplastic cell transformation serves as an indicator for the oncogenic potential of radiation exposure. It can be measured for a small number of ion and energy combinations. However, due to the complexity of the radiation field it is necessary to know the contribution to the radiation damage of each ion species for the entire range of energies. Therefore, a model is required which transfers the few experimental data to other particles with different LETs. We use the Local Effect Model (LEM) (2) with its cluster extension (3) to calculate the relative biological effectiveness (RBE) of neoplastic transformation. It was originally developed in the framework of hadrontherapy and is applicable for a large range of ions and energies. The input parameters for the model include the linear-quadratic parameters for the induction of lethal events as well as for the induction of transformation events per surviving cell. Both processes of cell inactivation and neoplastic transformation per viable cell are combined to eventually yield the RBE for cell transformation. We show that the Local Effect Model is capable of predicting the RBE of neoplastic cell transformation for a broad range of ions and energies. The comparison of experimental data (4) with model calculations shows a reasonable agreement. We find that the cluster extension results in a better representation of the measured RBE values. With this model it should be possible to better predict the risk of the complex mixed radiation field occurring in deep space. 1. F. A. Cucinotta and M. Durante, Lancet Oncol. 7, 431-435 (2006). 2. M. Scholz and G. Kraft, Radiat. Prot. Dosim. 52, 29-33 (1994). 3. Th. Elssser and M. Scholz, Radiat. Res. 167, 319-329 (2007). a 4. R. C. Miller, S. A. Marino, D. J. Brenner, S. G. Martin, M. Richards, G. Randers-Pehrson, and E. J. Hall, Radiat. Res. 142, 54-60 (1995).

Elssser, Thilo

82

Radiation Protection  

NASA Astrophysics Data System (ADS)

Radiation protection is a very important aspect for the application of particle detectors in many different fields, like high energy physics, medicine, materials science, oil and mineral exploration, and arts, to name a few. The knowledge of radiation units, the experience with shielding, and information on biological effects of radiation are vital for scientists handling radioactive sources or operating accelerators or X-ray equipment. This article describes the modern radiation units and their conversions to older units which are still in use in many countries. Typical radiation sources and detectors used in the field of radiation protection are presented. The legal regulations in nearly all countries follow closely the recommendations of the International Commission on Radiological Protection (ICRP). Tables and diagrams with relevant information on the handling of radiation sources provide useful data for the researcher working in this field.

Grupen, Claus

83

Atoms, radiation, and radiation protection  

Microsoft Academic Search

This book describes basic atomic and nuclear structure, the physical processes that result in the emission of ionizing radiations, and external and internal radiation protection criteria, standards, and practices from the standpoint of their underlying physical and biological basis. The sources and properties of ionizing radiation-charged particles, photons, and neutrons-and their interactions with matter are discussed in detail. The underlying

1986-01-01

84

Radiating Charge  

NSDL National Science Digital Library

The electric field lines from a point charge evolve in time as the charge moves. Watch radiation propagate outward at the speed of light as you wiggle the charge. Stop a moving charge to see bremsstrahlung (braking) radiation. Explore the radiation patterns as the charge moves with sinusoidal, circular, or linear motion. You can move the charge any way you like, as long as you dont exceed the speed of light.

Simulations, Phet I.; Dubson, Michael; Paul, Ariel

2013-02-01

85

Hawking radiation  

NASA Astrophysics Data System (ADS)

Hawking radiation is the thermal radiation predicted to be spontaneously emitted by black holes. It arises from the steady conversion of quantum vacuum fluctuations into pairs of particles, one of which escaping at infinity while the other is trapped inside the black hole horizon. It is named after the physicist Stephen Hawking who derived its existence in 1974. This radiation reduces the mass of black holes and is therefore also known as black hole evaporation.

Parentani, Renaud; Spindel, Philippe

2011-12-01

86

Radiation protection.  

PubMed

One of radiologic technologists' most important professional obligations is protecting patients, other members of the health care team, the public and themselves from as much radiation-related harm as possible while also maximizing the screening, diagnostic and therapeutic potential of ionizing radiation. This article reviews the different types of radiation dose and how radiation affects the body. Patient shielding, personnel dosimeters and area monitors are discussed, along with beam collimation and filtration. The author also describes protocols to protect pregnant patients and pregnant technologists. PMID:17519374

Brusin, Joyce Helena

87

Radiation enteritis  

SciTech Connect

Acute radiation enteritis is almost inevitable in the curative treatment of malignant tumors of the abdomen and pelvic area. It is frequently a self-limiting disorder of intestinal function associated with reversible mucosal changes of the intestine. The prevalence of chronic radiation enteritis has been underestimated in most surgical series and the majority of patients with symptoms probably do not seek medical advice until a serious complication occurs. Although associated with specific histologic features, the mechanism of chronic radiation injury is poorly understood. The prevalence, pathogenesis, diagnosis and approaches to the treatment and prevention of acute and chronic radiation enteritis are discussed herein. Recent investigative techniques should lead to a better understanding of the physiopathologic characteristics of radiation enteritis and, thereby, provide a more rational basis for treatment which, at the present time, is unsatisfactory. Attempts to reduce the prevalence of radiation enteritis should be directed toward careful patient selection for radiation treatment of the pelvis and to minimize injury to the small intestine, by reducing the volume of small intestine in the radiation area and providing more individualized dosimetry. 71 references.

Yeoh, E.K.; Horowitz, M.

1987-10-01

88

COSMIC RADIATION  

Microsoft Academic Search

Observations made rn the universe concemrng cosmic radiatron are ; discussed. Cosmic radiation on its way to earth traverses an area which ; influences its rntensity. ln crossing the geomagnetic field part of the cosmic ; radiation is diverted. Intensity depends on latitude and partly on elevation of ; the observatron point. Cosmic radiatron is also influenced by changing air

Svoboda

1960-01-01

89

Hawking Radiation  

NSDL National Science Digital Library

This resource presents explanations and sample calculations of: the event horizon (or Schwarzschild radius) of a black hole mass; the lifetime of virtual photons; the frequency of Hawking radiation; and black hole temperature, luminosity, and lifetime. Background information is provided on the classical law of gravitation, gravitational potential energy, the quantization of energy, black body radiation, and the equivalence of mass and energy.

90

Radiation therapy  

MedlinePLUS

... can also damage or kill healthy cells. The death of healthy cells can lead to side effects. These side effects depend on the dose of radiation, and how often you have the therapy. External beam radiation may cause skin changes, such as hair loss, red or ...

91

Understanding Radiation.  

ERIC Educational Resources Information Center

|Radiation is a natural energy force that has been a part of the environment since the Earth was formed. It takes various forms, none of which can be smelled, tasted, seen, heard, or felt. Nevertheless, scientists know what it is, where it comes from, how to measure and detect it, and how it affects people. Cosmic radiation from outer space and

Department of Energy, Washington, DC. Nuclear Energy Office.

92

Radiation dosimetry  

Microsoft Academic Search

This book consists of five papers on the following topics: bioeffect dosimetry in radiation therapy; a comparison of national and international megavoltage calibration protocols; recent advances in electron and photon dosimetry; microdosimetry and its application to biological processes; and ultraviolet radiation dosimetry and measurement.

Orton

1985-01-01

93

RADIATION BALANCE  

Technology Transfer Automated Retrieval System (TEKTRAN)

The balance of energy on the earth's surface represents the difference between incoming and outgoing radiation. There are two components in both the incoming and ongoing fractions and are separated by wavelength as shortwave (less than 5 um) and longwave (greater than 5 um). Shortwave radiation or...

94

Radiation detector  

DOEpatents

Apparatus is provided for detecting radiation such as gamma rays and x-rays generated in backscatter Moessbauer effect spectroscopy and x-ray spectrometry, which has a large window for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.

Fultz, B.T.

1980-12-05

95

Radiation detector  

DOEpatents

Apparatus is provided for detecting radiation such as gamma rays and X-rays generated in backscatter Mossbauer effect spectroscopy and X-ray spectrometry, which has a large "window" for detecting radiation emanating over a wide solid angle from a specimen and which generates substantially the same output pulse height for monoenergetic radiation that passes through any portion of the detection chamber. The apparatus includes a substantially toroidal chamber with conductive walls forming a cathode, and a wire anode extending in a circle within the chamber with the anode lying closer to the inner side of the toroid which has the least diameter than to the outer side. The placement of the anode produces an electric field, in a region close to the anode, which has substantially the same gradient in all directions extending radially from the anode, so that the number of avalanche electrons generated by ionizing radiation is independent of the path of the radiation through the chamber.

Fultz, Brent T. (Berkeley, CA)

1983-01-01

96

Synchrotron Radiation  

SciTech Connect

This book covers the physical aspects of synchrotron radiation generation and is designed as a textbook and reference for graduate students, teachers and scientists utilizing synchrotron radiation. It is my hope that this text may help especially students and young researchers entering this exciting field to gain insight into the characteristics of synchrotron radiation. Discovered in 1945, synchrotron radiation has become the source of photons from the infrared to hard x-rays for a large community of researchers in basic and applied sciences. This process was particularly supported by the development of electron accelerators for basic research in high energy physics. Specifically, the development of the store ring and associated technologies resulted in the availability of high brightness photon beams far exceeding other sources. In this text, the physics of synchrotron radiation for a variety of magnets is derived from first principles resulting in useful formulas for the practitioner. Since the characteristics and quality of synchrotron radiation are intimately connected with the accelerator and electron beam producing this radiation, a short overview of relevant accelerator physics is included.

Wiedemann, Helmut

2003-08-11

97

Radiation Safety  

Center for Food Safety and Applied Nutrition (CFSAN)

... Safe and Unaffected by Radiation Contamination from Japanese Nuclear Power Plant Incident; US Monitoring Control Strategy Explained (PDF ... More results from www.fda.gov/food/recalls,%20outbreaks%20&%20emergencies/emergencies

98

Healthful radiation  

SciTech Connect

This title of this article sounds paradoxical to most people because the general public is not fully aware of the many benefits radiation has brought to people`s healthcare. Radiation has provided the most effective means of noninvasive diagnosis of many diseases, thus reducing the need for exploratory surgery, at significantly reduced risks. Furthermore, radiotherapy has been effective in treating many diseases without surgical removal of the diseased part. The breast is one excellent example of the benefits of radiation in both diagnosis and treatment with preservation. Yet the public still regards radiation as mysterious and dangerous, while trained experts regard it as beneficial with manageable risks. This article suggests ways of presenting this material to the public in a manner that is interesting and informative. 11 refs.

Agard, E.T. [Flowers Hospital, Sylvania, OH (United States)

1997-01-01

99

Blackbody Radiation  

NSDL National Science Digital Library

This website, from the University of Winnipeg, offers an explanation of blackbody radiation. The page also provides a brief history, describing its discovery and its implications in modern physics. Several graphs and images are included to aid in the explanation.

2008-09-10

100

Radiation Emergencies  

MedlinePLUS

... EMS Providers Related Links Natural Disasters & Severe Weather Earthquakes Extreme Heat Floods Hurricanes Preparedness Get Supplies Make ... see what you can do. CDC Responds to Earthquake, Tsunami, and Radiation Release in Japan Information on ...

101

RADIATION DETECTOR  

DOEpatents

A radiation detector of the type is described wherein a condenser is directly connected to the electrodes for the purpose of performing the dual function of a guard ring and to provide capacitance coupling for resetting the detector system.

Wilson, H.N.; Glass, F.M.

1960-05-10

102

Radiation Fog  

NSDL National Science Digital Library

This is the first instructional component to be published in the Physical Processes Professional Competency Unit of the Forecasting Low-Altitude Clouds and Fog for Aviation Operations Professional Development Series. The learning modules in this professional competency unit will help aviation forecasters gain more familiarity with the physical concepts and atmospheric conditions related to fog and low stratus life cycles. Such understanding, in turn, can help forecasters more efficiently and accurately evaluate the ability of a given atmospheric environment to generate and/or maintain radiation fog. Radiation Fog presents presents the physical processes and life cycle of radiation fog, including its preconditioning environment, initiation, growth, and dissipation. The processes include radiation (both solar and longwave), soil-atmosphere thermal interactions, turbulent mixing, the roles of condensation nuclei, and droplet settling. Each section includes a set of interactive questions based on the learning content presented.

Spangler, Tim

2000-12-01

103

Radiation Emergencies  

Center for Drug Evaluation (CDER)

... Safety (3/2011); Radiation Emergencies (Centers for Disease Control and Prevention). ... increase the rates of elimination of these substances from the ... More results from www.fda.gov/drugs/emergencypreparedness/bioterrorismanddrugpreparedness

104

Radiation enteritis  

SciTech Connect

As the population receiving radiation therapy grows, so does the incidence of chronic radiation enteritis. A review of the pathology of chronic radiation enteritis reveals fibrosis, endarteritis, edema, fragility, perforation, and partial obstruction. Conservative management of patients with this disease is common. Because the obstruction is only partial, decompression is easily achieved with nasogastric suction and parenteral support. The patient is then often discharged on a liquid-to-soft diet. This therapeutic strategy does nothing for the underlying pathology. The problem, sooner or later, will return with the patient further depleted by the chronic radiation enteritis. We think surgical intervention is appropriate when the diagnosis of chronic radiation enteritis is assumed. The surgery in relation to this disease is high risk with a 30% mortality and 100% expensive morbidity. Early intervention seems to decrease these figures. All anastomoses, if possible, should be outside the irradiated area. Trapped pelvic loops of intestine should be left in place and a bypass procedure with decompressing enterostomies accomplished. The surgery should be performed by a surgeon with extensive experience with all kinds of bowel obstruction as well as experience in performing surgery in radiated tissue.

O'Brien, P.H.; Jenrette, J.M. III; Garvin, A.J.

1987-09-01

105

Radiation Therapy (For Parents)  

MedlinePLUS

... have many questions and concerns about it. About Radiation Therapy In radiation therapy, high-energy radiation from ... to remove tumors or cancerous areas. Continue How Radiation Is Given Radiation therapy is administered two ways: ...

106

Radiation Doses in Perspective  

MedlinePLUS

... Health Effects Ionizing & Non-Ionizing Radiation Understanding Radiation: Radiation Doses in Perspective Health Effects Main Page Exposure ... Sources Doses from Common Radiation Sources Average U.S. Radiation Doses and Sources All of us are exposed ...

107

(Radiation protection)  

SciTech Connect

The traveler attended the Seventh Congress of the International Radiation Protection Association (IRPA) in Sydney, Australia, April 11--15, 1988. This conference consisted of a comprehensive technical program with oral and poster presentations in all areas of radiation protection including several topics which were of special interest to the traveler; e.g., neutron dosimetry, personnel dosimetry and instrumentation, radiobiology, and radiation accidents. Besides attending technical sessions, the traveler presented a paper on results and implications of neutron personnel dosimetry intercomparison studies conducted since 1974 at the Oak Ridge National Laboratory (ORNL). During the meeting, the traveler discussed possible future collaborative research efforts with scientists from several countries and obtained commitments for an ORNL-coordinated radiation protection conference planned for November of 1988. Through the conference attendance and discussions with dosimetry researchers, the traveler gained information concerning directions and philosophies in radiation protection and dosimetry and made preliminary plans for future cooperative efforts which will be directly related to Department of Energy (DOE) programs.

Swaja, R.E.

1988-05-06

108

RADIATION INTEGRATOR  

DOEpatents

Radiation detecting and measuring systems, particularly a compact, integrating, background monitor, are discussed. One of the principal features of the system is the use of an electrometer tube where the input of the tube is directly connected to an electrode of the radiation detector and a capacitor is coupled to the tube input. When a predetermined quantity of radiation has been integrated, a trigger signal is fed to a recorder and a charge is delivered to the capacitor to render the tube inoperative. The capacitor is then recharged for the next period of operation. With this arrangement there is a substantial reduction in lead lengths and the principal components may be enclosed and hermetically sealed to insure low leakage.

Glass, F.M.; Wilson, H.N.

1959-02-17

109

Radiation effects.  

PubMed

International Commission on Radiological Protection (ICRP) Committee 1 (C1) considers the risk of induction of cancer and heritable disease; the underlying mechanisms of radiation action; and the risks, severity, and mechanisms of induction of tissue reactions (formerly 'deterministic effects'). C1 relies upon the interpretation of current knowledge of radio-epidemiological studies; current information on the underlying mechanisms of diseases and radiation-induced disease; and current radiobiological studies at the whole animal, tissue, cell, and molecular levels. This overview will describe the activities of C1 in the context of the 2007 Recommendations of ICRP. In particular, the conclusions from the most recent C1 Task Group deliberations on radon and lung cancer, and tissue reactions will be discussed. Other activities are described in summary fashion to illustrate those areas that C1 judge to be likely to influence the development of the risk estimates and nominal risk coefficients used for radiation protection purposes. PMID:23088999

Preston, R J

2012-08-22

110

Radiation limits  

SciTech Connect

Recently several changes were made to the regulations governing the limits of allowable exposure to radiation for industrial radiographers and nuclear power plant workers. Even though these regulations effect people who have been trained and educated about radiation`s dangers, changes still bring up many common questions that may not be readily answered by the regulations themselves. This paper will attempt to answer some of the more common and relevant questions that are being asked in industry. Who is involved in setting the regulations and standards? (Who are ``They?``) What are the differences between the old and the new regulations? Why did the regulations change? How do ``They`` know what is safe? Have these standards been changed before? Will there be future changes?

Hassard, M. [Salt Lake Community Coll., Salt Lake City, UT (United States)

1997-09-01

111

Radiation receiver  

DOEpatents

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles. 5 figs.

Hunt, A.J.

1983-09-13

112

Radiation receiver  

DOEpatents

The apparatus for collecting radiant energy and converting same to alternate energy form includes a housing having an interior space and a radiation transparent window allowing, for example, solar radiation to be received in the interior space of the housing. Means are provided for passing a stream of fluid past said window and for injecting radiation absorbent particles in said fluid stream. The particles absorb the radiation and because of their very large surface area, quickly release the heat to the surrounding fluid stream. The fluid stream particle mixture is heated until the particles vaporize. The fluid stream is then allowed to expand in, for example, a gas turbine to produce mechanical energy. In an aspect of the present invention properly sized particles need not be vaporized prior to the entrance of the fluid stream into the turbine, as the particles will not damage the turbine blades. In yet another aspect of the invention, conventional fuel injectors are provided to inject fuel into the fluid stream to maintain the proper temperature and pressure of the fluid stream should the source of radiant energy be interrupted. In yet another aspect of the invention, an apparatus is provided which includes means for providing a hot fluid stream having hot particles disbursed therein which can radiate energy, means for providing a cooler fluid stream having cooler particles disbursed therein, which particles can absorb radiant energy and means for passing the hot fluid stream adjacent the cooler fluid stream to warm the cooler fluid and cooler particles by the radiation from the hot fluid and hot particles.

Hunt, Arlon J. (Oakland, CA)

1983-01-01

113

Radiation dermatitis  

SciTech Connect

Even in this era of modern radiotherapy, injuries associated with the medical and industrial use of radiation devices will continue to pose a difficult problem for the reconstructive surgeon. It must be borne in mind that the single most serious hazard to surgery in irradiated tissue is the lodgement of bacteria in tissue rendered avascular by the radiation and the secondary necrosis from the infection itself. The basic principles of wound management must be augmented by thorough knowledge of the use of well-vascularized muscle and musculocutaneous flap to provide adequate, blood-rich, soft-tissue coverage.

Shack, R.B.; Lynch, J.B.

1987-04-01

114

Counterbalanced radiation detection system  

SciTech Connect

A counterbalanced radiation detection system is described comprising: (a) a stand; (b) a first radiation detector; (c) a first radiation detector arm means for tiltably connecting the first radiation detector with the stand; (d) a second radiation detector; (e) a second radiation detector arm means for tiltably connecting the second radiation detector with the stand, whereby the tilting angles of the radiation detector arm means define a distance between the radiation detectors; and (f) a torque transforming means connected between the first and second radiation detector arm means for transforming the torque created by one of the radiation detectors in a sense opposed to the torque created by the other radiation detector.

Platz, W.

1987-03-24

115

Ionizing radiation  

Technology Transfer Automated Retrieval System (TEKTRAN)

This chapter gives a comprehensive review on ionizing irradiation of fresh fruits and vegetables. Topics include principles of ionizing radiation, its effects on pathogenic and spoilage microorganisms, shelf-life, sensory quality, nutritional and phytochemical composition, as well as physiologic and...

116

RADIATION DOSIMETER  

Microsoft Academic Search

An improvement was made in the determination of amounts of ionizing ; radiation, particularly low-energy beta particles of less than 1000 rad total ; dose by means of fluid-phase dosimeter employing a stabilized-- sensitized ; ferrous-ferric colorimetric system in a sulphuric acid medium. The improvement ; in the dosimeter consists of adding to the ferrous-ferric system in ; concentrations of

W. R. Jr. Balkwell; G. D. Jr. Adams

1960-01-01

117

Radiation accidents  

SciTech Connect

It is essential that emergency physicians understand ways to manage patients contaminated by radioactive materials and/or exposed to external radiation sources. Contamination accidents require careful surveys to identify the metabolic pathway of the radionuclides to guide prognosis and treatment. The level of treatment required will depend on careful surveys and meticulous decontamination. There is no specific therapy for the acute radiation syndrome. Prophylactic antibodies are desirable. For severely exposed patients treatment is similar to the supportive care given to patients undergoing organ transplantation. For high-dose extremity injury, no methods have been developed to reverse the fibrosing endarteritis that eventually leads to tissue death so frequently found with this type of injury. Although the Three Mile Island episode of March 1979 created tremendous public concern, there were no radiation injuries. The contamination outside the reactor building and the release of radioiodine were negligible. The accidental fuel element meltdown at Chernobyl, USSR, resulted in many cases of acute radiation syndrome. More than 100,000 people were exposed to high levels of radioactive fallout. The general principles outlined here are applicable to accidents of that degree of severity.

Saenger, E.L.

1986-09-01

118

Radiation Emergencies  

MedlinePLUS

... enough, it can cause premature aging or even death. Although there are no guarantees of safety during a radiation emergency, you can take actions to protect yourself. You should have a disaster plan. Being prepared can help reduce fear, anxiety and losses. Centers for Disease Control and ...

119

Radiation Belts  

NSDL National Science Digital Library

This article provides an outline of the motion of charged particles in the Earth's magnetic fields, and the Van Allen and outer radiation belts. It summarizes their discovery, their properties and their physics, as well as providing links to background materials and additional information. This is part of a large web site on the Exploration of the Earth's Magnetosphere. A Spanish translation is available.

Stern, David

2005-09-19

120

Radiation cataract.  

PubMed

Until very recently, ocular exposure guidelines were based on the assumption that radiation cataract is a deterministic event requiring threshold doses generally greater than 2 Gy. This view was, in part, based on older studies which generally had short follow-up periods, failed to take into account increasing latency as dose decreased, had relatively few subjects with doses below a few Gy, and were not designed to detect early lens changes. Newer findings, including those in populations exposed to much lower radiation doses and in subjects as diverse as astronauts, medical workers, atomic bomb survivors, accidentally exposed individuals, and those undergoing diagnostic or radiotherapeutic procedures, strongly suggest dose-related lens opacification at significantly lower doses. These observations resulted in a recent re-evaluation of current lens occupational exposure guidelines, and a proposed lowering of the presumptive radiation cataract threshold to 0.5 Gy/year and the occupational lens exposure limit to 20 mSv/year, regardless of whether received as an acute, protracted, or chronic exposure. Experimental animal studies support these conclusions and suggest a role for genotoxicity in the development of radiation cataract. Recent findings of a low or even zero threshold for radiation-induced lens opacification are likely to influence current research efforts and directions concerning the cellular and molecular mechanisms underlying this pathology. Furthermore, new guidelines are likely to have significant implications for occupational and/or accidental exposure, and the need for occupational eye protection (e.g. in fields such as interventional medicine). PMID:23089007

Kleiman, N J

2012-08-22

121

Radiation Therapy for Osteosarcoma  

MedlinePLUS

... for osteosarcoma Next Topic Clinical trials for osteosarcoma Radiation therapy for osteosarcoma Radiation therapy uses high-energy rays ... major role in treating this disease. External beam radiation therapy This is the type of radiation therapy most ...

122

Gallbladder Cancer: Radiation Therapy  

MedlinePLUS

... gallbladder cancer Next Topic Chemotherapy for gallbladder cancer Radiation therapy for gallbladder cancer Radiation therapy uses high- ... higher dose to the cancer areas. Uses of radiation therapy Radiation therapy may be used in several ...

123

Radiation Protection  

NSDL National Science Digital Library

Chemotherapy and radiation can be powerful weapons against cancer. But they harm healthy cells as well. Cells of the immune system and G.I. tract are especially vulnerable: instead of repairing the damage, they respond by committing cellular suicide. In contrast, tumor cells have mutations that make them resistant to cell death. Roswell Park Cancer Institute researcher Andrei Gudkov and his colleagues recently harnessed this property to create a new drug.

Science Update (AAAS;)

2008-05-01

124

Radiation protection in space.  

PubMed

Radiation environment, basic concepts of radiation protection, and specific aspects of the space radiation field are reviewed. The discussion of physico-chemical and subcellular radiation effects includes mechanisms of radiation action and cellular consequences. The discussion of radiobiological effects includes unique aspects of HZE particle effects, space flight findings, terrestrial findings, analysis of somatic radiation effects and effects on critical organs, and early and delayed effects. Other topics include the impact of the space flight environment, measurement of radiation exposure, establishing radiation protection limits, limitations in establishing space-based radiation exposure limits, radiation protection measures, and recommendations. PMID:11541474

Reitz, G; Facius, R; Sandler, H

125

Radiating gravastars  

NASA Astrophysics Data System (ADS)

Considering a Vaidya exterior spacetime, we study dynamical models of prototype gravastars, made of an infinitely thin spherical shell of a perfect fluid with the equation of state p = ?, enclosing an interior de Sitter spacetime. We show explicitly that the final output can be a black hole, an unstable gravastar, a stable gravastar or a "bounded excursion" gravastar, depending on how the mass of the shell evolves in time, the cosmological constant and the initial position of the dynamical shell. This work presents, for the first time in the literature, a gravastar that emits radiation.

Chan, R.; da Silva, M. F. A.; Villas da Rocha, Jaime F.; Wang, Anzhong

2011-10-01

126

Radiation dosimeters  

SciTech Connect

This patent describes a radiation dosimeter badge having at least a first part and a second part; at least one of the parts including a dosimeter holder for holding at least one luminescent dosimeter; the first and second parts being controllably detachable using a rotatable mechanical connection. It comprises a tamper-resistant means to controllably resist unauthorized detachment of the first and second parts of the dosimeter badge; the tamper-resistance means including a tamper ring which engages to resist movement of a rotatable locking ring which is movable to controllably restrain the second and first parts of the dosimeter badge.

Hoelsher, J.W.; Hegland, J.E.; Braunlich, P.F.; Tetzlaff, W.

1992-01-21

127

Handling of Radiation Accidents.  

National Technical Information Service (NTIS)

The book deals with one of the most important questions in the practice of radiation safety: the radiation hazards. Chapter I ''Radiation hazards - fundamental concepts, determination and examples'' gives the definition of the concept ''hazard'' and the c...

M. A. Mikhajlov G. Vasilev

1978-01-01

128

Solar radiation resource assessment  

SciTech Connect

The bulletin discusses the following: introduction; Why is solar radiation resource assessment important Understanding the basics; the solar radiation resource assessment project; and future activities.

Not Available

1990-11-01

129

Radiation and People  

ERIC Educational Resources Information Center

|Describes the development of radiation as a tool of medicine. Includes topics on history of radiation, electromagnetic spectrum, X-ray tubes, high energy machines, radioactive sources, artificial radioactivity, radioactive scanning, units, present radiation background, and effect of radiation on living tissue. (DS)|

Freilich, Florence G.

1970-01-01

130

Radiation detection and measurement  

Microsoft Academic Search

Introductory material covers radiation sources, radiation interactions, general properties of radiation detectors, and counting statistics and error prediction. This is followed by detailed sections on gas-filled detectors, scintillation counters, semiconductor detectors, neutron detectors and spectroscopy, detector electronics and pulse processing, and miscellaneous radiation detectors and applications.

Glenn F. Knoll

1979-01-01

131

Radiation and People  

ERIC Educational Resources Information Center

Describes the development of radiation as a tool of medicine. Includes topics on history of radiation, electromagnetic spectrum, X-ray tubes, high energy machines, radioactive sources, artificial radioactivity, radioactive scanning, units, present radiation background, and effect of radiation on living tissue. (DS)

Freilich, Florence G.

1970-01-01

132

Why "Radiation Oncology"  

PubMed Central

Radiotherapy continues to be a major treatment for solid tumours and is a cornerstone of modern oncology. The term 'radiation oncology' describes the integration of radiation therapy into the complexity of multi-modal therapy. Over the last ten years the crucial role of radiation therapy as part of multi-modality protocols in cancer care has been documented in numerous Phase III trials. Advances in treatment technology as well as the underlying biology of tumour resistance mechanisms will further strengthen the role of radiation oncology. The scientific role of radiation oncology is reflected by the increase in the number of papers related to radiation oncology in resources like Medline. In order to reflect the growing scientific importance of radiation oncology, radiation physics and radiation biology, we have initiated Radiation Oncology as the first open access journal in the field. Open access allows for a rapid and transparent publication process together with an unequalled opportunity to reach the widest reader spectrum possible.

Belka, Claus; Camphausen, Kevin A

2006-01-01

133

Radiation transport calculations for cosmic radiation.  

PubMed

The radiation environment inside and near spacecraft consists of various components of primary radiation in space and secondary radiation produced by the interaction of the primary radiation with the walls and equipment of the spacecraft. Radiation fields inside astronauts are different from those outside them, because of the body's self-shielding as well as the nuclear fragmentation reactions occurring in the human body. Several computer codes have been developed to simulate the physical processes of the coupled transport of protons, high-charge and high-energy nuclei, and the secondary radiation produced in atomic and nuclear collision processes in matter. These computer codes have been used in various space radiation protection applications: shielding design for spacecraft and planetary habitats, simulation of instrument and detector responses, analysis of absorbed doses and quality factors in organs and tissues, and study of biological effects. This paper focuses on the methods and computer codes used for radiation transport calculations on cosmic radiation, and their application to the analysis of radiation fields inside spacecraft, evaluation of organ doses in the human body, and calculation of dose conversion coefficients using the reference phantoms defined in ICRP Publication 110. PMID:23089013

Endo, A; Sato, T

2012-08-22

134

Radiation applications: An overview  

SciTech Connect

Radiation has been successfully utilized for medical, industrial, and research applications since Roentgen first discovered X rays in the late 19th century. Today, intense fields of electron, photon, and neutron radiation are used for defense applications, and industrial processing, and both radiation sources and focused beams of radiation are routinely used in medicine for therapy and imaging. These advances in radiation technology have been coupled with the development of high-power reactors and high-power accelerators as well as continued improvements in the dosimetry of the delivered radiation. Radiation also can be a problem that must be dealt with. Aside from the obvious need to shield people and critical apparatus from the harmful effects of ionizing radiation, there are cases where the system must be designed to operate successfully in a radiation field. Reactor components such as fuel, internals, and pressure vessels must operate in neutron fields; fusion systems must operate in intense high-energy neutron fields; microelectronics used in space must operate in electron, proton, and cosmic ray fields; and accelerator components must operate in proton, neutron, and photon fields. Frequently, these components cannot be tested directly in the radiation fields to which they will be subjected, so simulation of the radiation fields with reactors, accelerators, or radiation sources has been developed to cope with this problem. This paper focuses on current applications of radiation processing, radiation effects in electronics, and radiation imaging.

Block, R.C. (Rensselaer Polytechnic Institute, Troy, NY (United States))

1993-01-01

135

Influence of Extraterrestrial Radiation on Radiation Portal Monitors  

Microsoft Academic Search

Cosmic radiation and solar flares can be a major source of background radiation at the Earth's surface. This paper examines the relationship between extraterrestrial radiation and the detectable background in radiation portal monitors used for homeland security applications. Background radiation data from 13 radiation portal monitor facilities are examined and compared against external sources of data related to extraterrestrial radiation,

Paul E. Keller; Richard T. Kouzes

2009-01-01

136

Radiation protection guidelines for radiation emergencies  

SciTech Connect

The system of dose limitation and present guidance for emergency workers and guidance for intervention on behalf of the public are discussed. There are three elements for the system of dose limitation: justification, optimization and dose limits. The first element is basically a political process in this country. Justification is based on a risk-benefit analysis, and justification of the use of radioactive materials or radiation is generally not within the authority of radiation protection managers. Radiation protection managers typically assess detriments or harm caused by radiation exposure and have very little expertise in assessing the benefits of a particular practice involving nuclear material.

Lessard, E.T.; Meinhold, C.B.

1986-01-01

137

Introduction to radiation transport  

SciTech Connect

This lecture will present time-dependent radiation transport where the radiation is coupled to a static medium, i.e., the material is not in motion. In reality, radiation exerts a pressure on the materials it propagates through and will accelerate the material in the direction of the radiation flow. This fully coupled problem with radiation transport and materials in motion is referred to as radiation-hydrodynamics (or in a shorthand notation: rad-hydro) and is beyond the scope of this lecture.

Olson, G.L.

1998-12-31

138

Low Dose Radiation Research  

NSDL National Science Digital Library

The US Department of Energy's Low Dose Radiation Research Program supports research that investigates the health risks from exposure to radiation at low levels. This Web site provides an overview of radiation biology, up-to-date information and archived results from program-related research, and other resources for the benefit of researchers and the general public alike. Some research projects include comparing low dose radiation to endogenous oxidative damage, determining thresholds for radiation exposure, determining genetics factors that make some individuals more susceptible to radiation-induced damage, and more.

139

Radiation Safety or Radiation Hazard in Norway.  

National Technical Information Service (NTIS)

The report gives a survey of radiation dose (to the whole body or to certain organs) to the Norwegian population, caused by various radiation sources. It also estimates the probable number and category of injuries caused by these doses. Comparative evalua...

E. E. Pochin

1985-01-01

140

Radiation from hard objects  

SciTech Connect

The inference of the diameter of hard objects is insensitive to radiation efficiency. Deductions of radiation efficiency from observations are very sensitive - possibly overly so. Inferences of the initial velocity and trajectory vary similarly, and hence are comparably sensitive.

Canavan, G.H.

1997-02-01

141

Calculate Your Radiation Dose  

NSDL National Science Digital Library

This calculator by the Environmental Protection Agency allows you to estimate your annual radiation dose. The calculator is easy to use and the bottom of the page includes links to more information about radiation dosage.

2011-05-12

142

Automated Personnel Radiation Monitor.  

National Technical Information Service (NTIS)

An automated Personnel Low-Level Radiation Portal Monitor has been developed by UNC Nuclear Industries, Inc. It is micro-computer controlled and uses nineteen large gas flow radiation detectors. By employing a micro-computer, sophisticated mathematical an...

S. G. Sterling

1981-01-01

143

Radio Frequency Radiation Hazards.  

National Technical Information Service (NTIS)

Explains the biological (personnel) and non-biological (feed and fuel) effects of RF radiation. The frequency spectrum is explained and the difference between ionizing and non-ionizing radiation is illustrated.

1994-01-01

144

Fundamentals of Radiation Physics.  

National Technical Information Service (NTIS)

The Scientific Medical Effects of Ionizing Radiation Course, conducted once a year, focuses on the latest research about the medical effects of ionizing radiation to help clinicians, health physicists, and medical planners preserve troop health in the fac...

M. S. Smyczynski

2008-01-01

145

Nonionizing Radiation 583.  

National Technical Information Service (NTIS)

This document presents an introductory course on nonionizing radiation intended for industrial hygienists, health physicists, and other professional health personnel. Topics covered in the course include nonionizing radiation sources, the attendant hazard...

1977-01-01

146

Radiative Augmented Combustion.  

National Technical Information Service (NTIS)

Radiative Augmented Combustion has been identified as a potential technique for extending aircraft operating limits associated with combustion processes. This technique is based on the fact that radiation of selected wavelengths is capable of photodissoci...

M. Lavid

1984-01-01

147

Solar Cell Radiation Handbook.  

National Technical Information Service (NTIS)

A method is presented for predicting the degradation of a solar array in a space radiation environment. Solar cell technology which emphasizes the cell parameters that degrade in a radiation environment, is discussed along with the experimental techniques...

J. R. Carter H. Y. Tada

1973-01-01

148

Prostate Cancer (Radiation Therapy)  

MedlinePLUS

... control the cancer. If I choose surgery, will radiation treatment still be required? If your surgery is ... option with your physician team. If I choose radiation therapy, will surgical treatment still be an option? ...

149

Radiation effects in space  

SciTech Connect

The paper discusses the radiation environment in space that astronauts are likely to be exposed to. Emphasis is on proton and HZE particle effects. Recommendations for radiation protection guidelines are presented. (ACR)

Fry, R.J.M.

1986-01-01

150

Prostate radiation - discharge  

MedlinePLUS

... these side effects: Skin problems during or after prostate radiation treatment is rare. Your skin over the ... keeping or getting an erection may occur after prostate radiation therapy but may not be noticed for ...

151

Radiation and the Energy Balance: The Role of Radiation.  

National Technical Information Service (NTIS)

The role of radiation, cloud radiation interactions in the climate, and radiation processes in climate change are discussed. The geometrical constraints, calibration issues, and time sampling issues of measuring radiation fluxes, done from space, are cons...

R. Kandel

1991-01-01

152

Synchrotron-radiation research  

SciTech Connect

The use of radiation from synchrotron sources has started a renaissance in materials, physics, chemistry, and biology. Synchrotron radiation has advantages over conventional x rays in that its source brightness is a thousand times greater throughout a continuous energy spectrum, and resonances are produced with specific electron energy levels. Two major synchrotron radiation sources are operated by DOE: the Stanford Synchrotron Radiation Laboratory at SLAC, and the National Synchrotron Light Source at Brookhaven. (DLC)

Cunningham, J.E.

1982-01-01

153

Daily Radiation Balance  

NSDL National Science Digital Library

This lesson is designed to provide students an understanding of the extent to which radiative energy heats and cools the surface of Earth on a daily basis. Students will learn to calculate the total amount of incoming and outgoing radiation over a day. They will learn to determine how balanced the radiative system is over a particular location and try to determine whether the surface is in radiative equilibrium.

154

Planetary Radiation Budgets  

Microsoft Academic Search

The energy state of a planet depends fundamentally on its radiation budget. Measurements made from space over past decades have led to significant revisions of ground-based estimates, both of the reflected fraction (the Bond albedo) of solar radiative flux and of the emitted thermal infrared radiation flux, for the Earth as well as for the other planets. After a brief

Robert Kandel; Michel Viollier

2005-01-01

155

Packet Personal Radiation Monitor.  

National Technical Information Service (NTIS)

A personal radiation monitor of the chirper type is provided for detecting ionizing radiation. A battery powered high voltage power supply is used to generate and apply a high voltage bias to a G-M tube radiation sensor. The high voltage is monitored by a...

J. E. Phelps

1988-01-01

156

RADIATION SITES TECHNICAL WORKGROUP  

EPA Science Inventory

Much of the radiation expertise in EPA is located in the Region Offices. The EPA Radiation Sites Technical Workgroup is an interoffice technical workgroup within EPA which provides a focal point for radiation expertise. The Workgroup has members from each region, as well as the...

157

Hand held radiation detector  

Microsoft Academic Search

A hand-held radiation detector is described for measuring localized radiation at extremely low levels, the detector comprising: a housing including two peripherally engaged, axially extending, tubular members, one of the members being entirely insulative, the other of the members being metallic; a radiation window at one end of the metallic tubular member, the window including a metallic portion in electrical

Wijangco

1984-01-01

158

Radiation Monitoring by Minicomputer.  

National Technical Information Service (NTIS)

Radiation monitoring at the Los Alamos Scientific Laboratory (LASL) ranges from measuring the potential build-up of alpha particle radiation in the offices and laboratories of LASL to the detection of radiation leakage from nuclear tests at the Nevada Tes...

M. Seamons

1977-01-01

159

Radiation degradation of polymethacrylamide  

Microsoft Academic Search

The effects of radiation on polymers have been studied for many years. When polymers are subjected to ultraviolet light or ionizing radiation, chain scission and crosslinking are possible. The radiation degradations of several methacrylate type polymers were investigated. The primary polymer studied was polymethacrylamide (PMAAm). Ultraviolet irradiated PMAAm yielded a five line ESR spectrum with 22 gauss splitting which is

OConnor

1984-01-01

160

Radiation Oncology Annual  

Microsoft Academic Search

Radiation Oncology Annual presents analyses of the latest clinical, technical, and biological advances in the field. Review articles cover new single and combined modality treatments for specific tumors; emerging techniques and uses of radiotherapy; advances in radiation physics; dosimetry; and treatment planning; clinical applications of imaging in radiation oncology clinically relevant radiobiology and experimental radiotherapy findings. Special attention is devoted

T. L. Phillips; W. Wara; D. A. Pistenmaa

1983-01-01

161

Radiation port dermatophytosis  

SciTech Connect

We report two cases in which dermatophytic infection developed almost entirely within a radiation field mimicking an acute radiation effect. Radiotherapists and dermatologists should be aware of this possibility and be able to differentiate it from radiation dermatitis. Topical antifungal agents are the recommended treatment after diagnosis is established.

Rosen, T.; Dupuy, J.; Maor, M.; Altman, A.

1988-12-01

162

Radiation Research: Chemistry and Physics.  

National Technical Information Service (NTIS)

Papers in this Proceedings are grouped under the following headings: (1) primary processes in radiation physics and chemistry; (2) radiation chemistry - general chemistry; (3) radiation chemistry - DNA and model systems; (4) radiation chemistry - other mo...

J. J. Broerse G. W. Barendsen H. B. Kal A. J. van der Kogel

1983-01-01

163

Nonionizing Radiation Laboratory Manual (583).  

National Technical Information Service (NTIS)

A laboratory manual for the study of nonionizing radiation, designed for industrial hygienists, health physicists and other health personnel, is presented. Topics include nonionizing radiation sources, radiation hazards, and basic principles of radiation ...

1977-01-01

164

Radiation Therapy for Bone Cancer  

MedlinePLUS

... bone cancer Next Topic Chemotherapy for bone cancer Radiation therapy for bone cancer Radiation therapy uses high- ... control symptoms like pain and swelling. Intensity-modulated radiation therapy Intensity-modulated radiation therapy (IMRT) is an ...

165

Radiation Therapy for Malignant Mesothelioma  

MedlinePLUS

... malignant mesothelioma Next Topic Chemotherapy for malignant mesothelioma Radiation therapy for malignant mesothelioma Radiation therapy uses high- ... this form of treatment more useful. Uses of radiation therapy Radiation therapy may be used in different ...

166

Radiation protection for radiologic technologists.  

PubMed

This article provides a review and update on radiation protection principles. Major topics include the effects of radiation on the body, natural and artificial sources of radiation, the basic principles of radiation protection and recommended dose limits. PMID:10665051

Newman, J

167

Radiation detection system  

DOEpatents

A radiation detection system which utilizes the generation of Cerenkov light in and the transmission of that light longitudinally through fiber optic wave guides in order to transmit intelligence relating to the radiation to a remote location. The wave guides are aligned with respect to charged particle radiation so that the Cerenkov light, which is generated at an angle to the radiation, is accepted by the fiber for transmission therethrough. The Cerenkov radiation is detected, recorded, and analyzed at the other end of the fiber.

Nelson, Melvin A. (Santa Barbara, CA); Davies, Terence J. (Santa Barbara, CA); Morton, III, John R. (Livermore, CA)

1976-01-01

168

RADIATION WAVE DETECTOR  

DOEpatents

The detection of the shape and amplitude of a radiation wave is discussed, particularly an apparatus for automatically indicating at spaced lntervals of time the radiation intensity at a flxed point as a measure of a radiation wave passing the point. The apparatus utilizes a number of photomultiplier tubes surrounding a scintillation type detector, For obtainlng time spaced signals proportional to radiation at predetermined intervals the photolnultiplier tubes are actuated ln sequence following detector incidence of a predetermined radiation level by electronic means. The time spaced signals so produced are then separately amplified and relayed to recording means.

Wouters, L.F.

1958-10-28

169

Nuclear Energy: Radiation Exposure  

NSDL National Science Digital Library

This lesson provides an overview of the sources and potential effects of radiation exposure. Topics include the history of the United States' domestic nuclear power program, the concept of ionizing radiation, and how radiation dosage is measured. There is also discussion of what constitutes a lethal dose of radiation and potential sources of exposure. The lesson includes an activity in which students measure their individual yearly exposures to radiation by making an inventory of lifestyle factors that affect their potential dosage and using an online calculator to sum up the contributions from the various sources.

Pratte, John

170

Synchrotron radiation from protons  

SciTech Connect

Synchrotron radiation from protons, though described by the same equations as the radiation from electrons, exhibits a number of interesting features on account of the parameters reached in praxis. In this presentation, we shall point out some of the features relating to (i) normal synchrotron radiation from dipoles in proton machines such as the High Energy Booster and the Superconducting Super Collider; (ii) synchrotron radiation from short dipoles, and its application to light monitors for proton machines, and (iii) synchrotron radiation from undulators in the limit when, the deflection parameter is much smaller than unity. The material for this presentation is taken largely from the work of Hofmann, Coisson, Bossart, and their collaborators, and from a paper by Kim. We shall emphasize the qualitative aspects of synchrotron radiation in the cases mentioned above, making, when possible, simple arguments for estimating the spectral and angular properties of the radiation. Detailed analyses can be found in the literature.

Dutt, S.K.

1992-12-01

171

Americans' Average Radiation Exposure  

SciTech Connect

We live with radiation every day. We receive radiation exposures from cosmic rays, from outer space, from radon gas, and from other naturally radioactive elements in the earth. This is called natural background radiation. It includes the radiation we get from plants, animals, and from our own bodies. We also are exposed to man-made sources of radiation, including medical and dental treatments, television sets and emission from coal-fired power plants. Generally, radiation exposures from man-made sources are only a fraction of those received from natural sources. One exception is high exposures used by doctors to treat cancer patients. Each year in the United States, the average dose to people from natural and man-made radiation sources is about 360 millirem. A millirem is an extremely tiny amount of energy absorbed by tissues in the body.

NA

2000-08-11

172

Radiation Damage Effects  

NASA Astrophysics Data System (ADS)

Radiation damage is an important issue for the particle detectors operated in a hostile environment where radiations from various sources are expected. This is particularly important for high energy physics detectors designed for the energy and intensity frontiers. This chapter describes the radiation damage effects in scintillating crystals, including the scintillation-mechanism damage, the radiation-induced phosphorescence, and the radiation-induced absorption. The radiation damage mechanism in crystal scintillators is also discussed. While the damage in halides is attributed to the oxygen/hydroxyl contamination, it is the structure defects, such as the oxygen vacancies, which cause the damage in oxides. Various material analysis methods used in investigations of the radiation damage effects as well as the improvement of crystal quality through systematic R&D are also presented.

Zhu, R.-Y.

173

Acute radiation syndrome and chronic radiation syndrome.  

PubMed

Acute radiation syndrome (ARS) or sickness or poisoning or toxicity is induced after a whole body exposure of men to high doses of radiation between 1-12Gy. First symptoms are from the gastrointestinal system, which together with bone marrow are the most sensitive parts of our body. Chronic radiation syndrome (CRS) may be induced by smaller than 1Gy radiation doses or after a mild form of ARS. Prophylaxis and treatment suggestions are described. In cases of ARS, a large part of the exposed population after proper medical care may survive, while without medical care this part of the population will be lost. Prophylaxis may also save another part of the population. PMID:23570025

Grammaticos, Philip; Giannoula, Evanthia; Fountos, George P

174

The Radiation Transport Conundrum in Radiation Hydrodynamics  

SciTech Connect

The summary of this paper is: (1) The conundrum in the title is whether to treat radiation in the lab frame or the comoving frame in a radiation-hydrodynamic problem; (2) Several of the difficulties are associated with combining a somewhat relativistic treatment of radiation with a non-relativistic treatment of hydrodynamics; (3) The principal problem is a tradeoff between easily obtaining the correct diffusion limit and describing free-streaming radiation with the correct wave speed; (4) The computational problems of the comoving-frame formulation in more than one dimension, and the difficulty of obtaining both exact conservation and full u/c accuracy argue against this method; (5) As the interest in multi-D increases, as well as the power of computers, the lab-frame method is becoming more attractive; and (6) The Monte Carlo method combines the advantages of both lab-frame and comoving-frame approaches, its only disadvantage being cost.

Castor, J I

2005-03-18

175

Complications of radiation therapy  

SciTech Connect

The skeletal effects of radiation are dependent upon many variables, but the pathologic features are consistent. Radiation may cause immediate or delayed cell death, cellular injury with recovery, arrest of cellular division, or abnormal repair with neoplasia. Radiation necrosis and radiation-induced neoplasm still occur despite the use of supervoltage therapy. Complications of radiotherapy are well known and have led to more judicious use of this therapeutic modality. With few exceptions, benign bone tumors are no longer treated with irradiation. Radiation necrosis may be difficult to differentiate from sarcoma arising in irradiated bone. They both occur within the field of irradiation. Radiation necrosis often has a long latent period which is, of course, the rule in radiation-induced neoplasia. A soft tissue mass favors the diagnosis of neoplasia, while its absence suggests radiation necrosis. Lack of pain favors necrosis. Calcification may occur in radiation necrosis and does not indicate neoplasia. A lack of progression on serial roentgenograms also favors radiation necrosis. 76 references.

Dalinka, M.K.; Mazzeo, V.P. Jr.

1985-01-01

176

Radiation physics, biophysics, and radiation biology  

SciTech Connect

Research at the Center for Radiological Research is a multidisciplenary blend of physics, chemistry and biology aimed at understanding the mechanisms involved in the health problems resulting from human exposure to ionizing radiations. The focus is increased on biochemistry and the application of the techniques of molecular biology to the problems of radiation biology. Research highlights of the program from the past year are described. A mathematical model describing the production of single-strand and double-strand breaks in DNA as a function radiation quality has been completed. For the first time Monte Carlo techniques have been used to obtain directly the spatial distribution of DNA moieties altered by radiation. This information was obtained by including the transport codes a realistic description of the electronic structure of DNA. We have investigated structure activity relationships for the potential oncogenicity of a new generation of bioreductive drugs that function as hypoxic cytotoxins. Experimental and theoretical investigation of the inverse dose rate effect, whereby medium LET radiations actually produce an c effect when the dose is protracted, is now at a point where the basic mechanisms are reasonably understood and the complex interplay between dose, dose rate and radiation quality which is necessary for the effect to be present can now be predicted at least in vitro. In terms of early radiobiological damage, a quantitative link has been established between basic energy deposition and locally multiply damaged sites, the radiochemical precursor of DNA double strand breaks; specifically, the spatial and energy deposition requirements necessary to form LMDs have been evaluated. For the first time, a mechanically understood biological fingerprint'' of high-LET radiation has been established. Specifically measurement of the ratio of inter-to intra-chromosomal aberrations produces a unique signature from alpha-particles or neutrons.

Hall, E.J.; Zaider, M.

1993-05-01

177

Neutron radiative capture  

SciTech Connect

This book presents a description of radiative capture processes at both low and high neutron energies; explains how calculations of the cross sections and spectra can be made and illustrates the techniques of capture measurements to form a coherent picture of the theory and applications of neutron capture. Contents include: Theory of Slow Neutron Radiative Capture: Introduction. Statistical theory of radiative capture. Neutron capture reaction mechanisms. Systematic properties of radiative neutron capture. Applications to stellar nucleosynthesis. Fast Neutron Radiative Capture: Direct and semidirect capture reactions. The compound nucleus model. Experimental results. Methods for calculating Neutron Cross Sections and Gamma-Ray Energy Spectra: Scope. Statistical model calculations. Expressions for El photon strengths. Giant dipole resonance systematics. Summary. Measurement Techniques for Radiative Neutron Capture: Introduction. Capture event detection. Analysis of measuarements. Neutron capture processes in fission reactors: Introduction. Capture in fertile and fissile nuclei. Capture in structural, coolout and shielding materials. Capture in fission product nuclei. The production of higher actinides.

Chrien, R.E.

1983-01-01

178

The flying radiation case  

SciTech Connect

The Los Alamos foil implosion program has the goal of producing an intense, high-energy density x-ray source by converting the energy of a magnetically imploded plasma into radiation and material energy. One of the methods for converting the plasma energy into thermal energy and radiation and utilizing it for experiments is called the flying radiation case (FRC). In this paper the authors shall model the FRC and provide a physical description of the processes involved. An analytic model of a planar FRC in the hydrodynamic approximation is used to describe the assembly and shock heating of a central cushion by a conducting liner driver. The results are also used to benchmark a hydrodynamics code for modeling an FRC. They then use a radiation-hydrodynamics computational model to explore the effects of radiation production and transport when a gold plasma assembles on a CH cushion. Results are presented for the structure and evolution of the radiation hohlraum.

Brownell, J.H.; Bowers, R.L. [Los Alamos National Lab., NM (United States). Applied Theoretical and Computational Physics Div.

1997-04-01

179

RHOBOT: Radiation hardened robotics  

SciTech Connect

A survey of robotic applications in radioactive environments has been conducted, and analysis of robotic system components and their response to the varying types and strengths of radiation has been completed. Two specific robotic systems for accident recovery and nuclear fuel movement have been analyzed in detail for radiation hardness. Finally, a general design approach for radiation-hardened robotics systems has been developed and is presented. This report completes this project which was funded under the Laboratory Directed Research and Development program.

Bennett, P.C.; Posey, L.D. [Sandia National Labs., Albuquerque, NM (United States)

1997-10-01

180

Spatially depolarised laser radiation  

SciTech Connect

The properties of polarisation-inhomogeneous laser radiation are considered taking into account its partial polarisation. It is shown that this radiation can be represented by a set of Hermite-Gaussian modes with different intensities and polarisations, and different coherence degrees. Devices having inhomogeneous depolarisation and polarisation are analysed. It is shown that the polarisation structure of polarisation-inhomogeneous radiation is not preserved during its propagation. (laser applications and other topics in quantum electronics)

Ishchenko, E F; Sokolov, A L [Moscow Power Engineering Institute, Moscow (Russian Federation)

2004-01-31

181

MULTIPOINT RADIATION MONITOR  

Microsoft Academic Search

A unique radiation monitor has been developed for performing wide-area field surveys for radiation sources. This device integrates the real-time output of multiple radiation detectors into a hand-held personal computer (e.g., a PDA) containing an intuitive graphical user interface. An independent hardware module supplies high voltage to the detectors and contains a rapid sampling system for transferring the detector count

K Hofstetter; D Donna Beals; K Ken Odell; R Robert Eakle; R Russell Huffman; L Larry Harpring

2006-01-01

182

Stereotactic Body Radiation Therapy  

Microsoft Academic Search

\\u000a Technological advancements in imaging and radiation planning and delivery have made it possible for cranial stereotactic radiosurgery\\u000a techniques to be applied to tumors outside of the brain. Although high-dose radiation therapy may be delivered in a single\\u000a fraction, referred to as extracranial stereotactic radiosurgery (SRS), more often, high-precision radiation is delivered in\\u000a more than one fraction, leading to the field

Laura A. Dawson

183

Radiation chemical synthesis  

SciTech Connect

The authors consider processes in radiation chemical synthesis which are being developed in various scientific-research organizations. The important advantages of radiation chlorination, viz. the lower temperature compared with the thermal method and the absence of dehydrochlorination products are discussed. The authors examine the liquid-phase chlorination of trifluorochloroethyltrichloromethyl ether to obtain the pentachloro-contining ether, trifluorodichloroethyltrichloromethyl ether. The authors discuss radiation synthesis processes that have be used formulated kinetic equations on which models have been based. It is concluded that the possibilities of preparative (micro- and low-tonnage) radiation synthesis are promising.

Zagoretz, P.A.; Poluetkov, V.A.; Shostenko, A.G.

1986-03-01

184

Solar radiation on Mars  

SciTech Connect

Detailed information on solar radiation characteristics on Mars are necessary for effective design of future planned solar energy systems operating on the surface of Mars. Presented here is a procedure and solar radiation related data from which the diurnally, hourly and daily variation of the global, direct beam and diffuse insolation on Mars are calculated. The radiation data are based on measured optical depth of the Martian atmosphere derived from images taken of the sun with a special diode on the Viking cameras; and computation based on multiple wavelength and multiple scattering of the solar radiation.

Appelbaum, J.; Flood, D.J.

1989-08-01

185

Radiation image inspection apparatus  

SciTech Connect

A radiation image inspection apparatus is described comprising: means for generating and directing radiation toward an article to be inspected; a screen for converting a radiation pattern of the article into a first visible light image; lens means for maintaining the intensity of a first visible light image produced on the screen; camera means having an image tube target and producing an electrical output system corresponding to the incident image on the image tube target from the lens means; and control means for controlling the operation of a camera means and the radiation generating means.

Velasquez, J.F.

1988-04-05

186

Radiation coloration resistant glass  

DOEpatents

A radiation coloration resistant glass is disclosed which is used in a radiation environment sufficient to cause coloration in most forms of glass. The coloration resistant glass includes higher proportions by weight of water and has been found to be extremely resistant to color change when exposed to such radiation levels. The coloration resistant glass is free of cerium oxide and has more than about 0.5% by weight water content. Even when exposed to gamma radiation of more than 10[sup 7] rad, the coloration resistant glass does not lose transparency. 3 figs.

Tomozawa, M.; Watson, E.B.; Acocella, J.

1986-11-04

187

Radiation physics, biophysics, and radiation biology  

SciTech Connect

The following research programs from the Center for Radiological Research of Columbia University are described: Design and development of a new wall-less ultra miniature proportional counter for nanodosimetry; some recent measurements of ionization distributions for heavy ions at nanometer site sizes with a wall-less proportional counter; a calculation of exciton energies in periodic systems with helical symmetry: application to a hydrogen fluoride chain; electron energy-loss function in polynucleotide and the question of plasmon excitation; a non-parametric, microdosimetric-based approach to the evaluation of the biological effects of low doses of ionizing radiation; high-LET radiation risk assessment at medium doses; high-LET radiobiological effects: increased lesion severity or increased lesion proximity; photoneutrons generated by high energy medical linacs; the biological effectiveness of neutrons; implications for radiation protection; molecular characterization of oncogenes induced by neutrons; and the inverse dose-rate effect for oncogenic transformation by charged particles is LET dependent.

Hall, E.J.

1992-05-01

188

Coherent synchrotron radiation and radiative electron polarization  

NASA Astrophysics Data System (ADS)

The process of radiative electron polarization through the mechanism of coherent synchrotron radiation (CSR) has been considered in the semi-classical approach. The CSR process is characterized by increasing photon emission probability from each electron proportional to number of electrons in a bunch if the wavelength of the emitted photon is greater than the bunch length. Estimations for built-up polarization of the electron beam Pcoh and the self-polarization time Tcoh caused by CSR mechanism were obtained and the comparison with ones for incoherent synchrotron radiation was performed. Despite the low probability of spin-flip transitions a significant particle polarization can be achieved for comparatively low values of the Lorentz factor (? <= 100) due to the huge number of photons emitted by each electron.

Potylitsyn, A. P.

2010-11-01

189

Radiation Therapy for Vaginal Cancer  

MedlinePLUS

... internal radiation with or without low doses of chemotherapy. Side effects of radiation therapy Radiation can destroy nearby healthy ... occur, but can be treated with medicines. These side effects tend to be worse when chemotherapy is given with radiation. Pelvic radiation can lead ...

190

Office of Radiation Programs Training Manual. Management of Radiation Accidents.  

National Technical Information Service (NTIS)

Contents: Radiation fundamentals; Radiation detection; Radiation protection; Sources of radioactivity; (Sealed sources, Sealed sources in medicine, Sealed sources in industry, Basin principles of nuclear reactors, Nuclear detonations and fallout); Radiati...

1970-01-01

191

Relativistic collapsing radiating stars  

NASA Astrophysics Data System (ADS)

A new class of exact solutions of Einstein's equations is proposed for a collapsing radiating spherically symmetric shear-free isotropic fluid undergoing radial heat flow. In remote past the solutions are static perfect fluid which then gradually starts evolving into radiating collapse. The interior solutions are matched with Vaidya exterior metric over the boundary.

Tewari, B. C.

2012-11-01

192

Earth radiation budgets  

Microsoft Academic Search

The annual and seasonal averaged earth atmosphere radiation budgets, derived from the most complete set of satellite observations available in late 1979, are presented. The budgets are derived using a composite of 48 monthly mean radiation budget maps. The annual, global average emitted infrared flux is 234 W\\/sq m, the planetary albedo is 0.30, and the net flux is zero

G. L. Stephens; G. G. Campbell; T. H. Vonder Haar

1981-01-01

193

The Planck Radiation Functions.  

ERIC Educational Resources Information Center

Blackbody radiation is used as an example to illustrate that oversimplification in teaching quantum ideas can result in later misunderstanding. Although textbooks give Planck's distribution function in terms of wavelength, there are actually 12 different radiation functions. Some of the more interesting ones are given and discussed. (JN)

Larsen, Russell D.

1985-01-01

194

On Blackbody Radiation.  

ERIC Educational Resources Information Center

The interrelationship between the various forms of the Planck radiation equation is discussed. A differential equation that gives intensity or energy density of radiation per unit wavelength or per unit frequency is emphasized. The Stefan-Boltzmann Law and the change in the glow of a hot body with temperature are also discussed. (KR)

Jain, Pushpendra K.

1991-01-01

195

The Pressure of Radiation  

Microsoft Academic Search

IN his letter of January 1 Prof. Callendar gives his reasons for doubting the formula for the pressure of radiation as it is usually accepted. He makes use of Boltzmann's proof of the fourth power law for the complete radiation, extends it to each separate frequency, and deduces that the energy in every frequency aught to be proportional to the

C. G. Darwin

1914-01-01

196

Radiation Exposure Compensation Program  

NSDL National Science Digital Library

This is the Justice Department's Radiation Exposure Compensation Program homepage. This site features information about the Radiation Exposure Compensation Act, including claimant categories, claim forms, and the Energy Employees Occupational Illness Compensation Program Act. This site also provides a table illustrating a summary of all claims received and compensation paid to date.

Program, U. S.

197

Forecasting Radiation Fog  

NSDL National Science Digital Library

The goal of this training module is to help you increase your understanding of how radiation fog forms, grows, and dissipates. Such understanding, in turn, can help you more efficiently and accurately evaluate the ability of a given atmospheric environment to generate and/or maintain radiation fog.

Spangler, Tim

1999-04-08

198

Impulse radiating antennas  

Microsoft Academic Search

A number of applications require radiation of a short pulse of electromagnetic energy out to large distances. These applications include target discrimination in a cluttered environment (e.g., looking over the ocean), aircraft identification by taking a 'TDR' of its major scattering centers, and target location through foliage. The Impulse Radiating Antenna (IRA) has generated widespread interest for its ability to

Carl E. Baum; Everett G. Farr

1993-01-01

199

Plastic plasticizer and radiation  

Microsoft Academic Search

Examination concerning the possibilities of decomposition of ; plasticizers such as phthalic acid esters and phosphoric acid esters or toxicity ; reduction thereof by the radiation has been made. (1) Radiation effects: Sham ; polluted solution having various kinds of concentrations of said ester was ; irradiated with ⁶°Co gamma -ray to 0.3 Mrad\\/hr. The results show that ; with

Sunada

1973-01-01

200

Chronic Radiation Enteritis  

Microsoft Academic Search

Chronic radiation enteritis is an increasing problem, as more patients receive radiotherapy as part of their cancer therapy and as the long-term survival of these patients improves. This review addresses the causes, investigation, treatment and prevention of this disease. A review of published studies was carried out using a variety of search terms, including radiation enteritis, investigation, treatment and prevention.

V. S. Theis; R. Sripadam; V. Ramani; S. Lal

2010-01-01

201

Synchrotron Radiation II.  

ERIC Educational Resources Information Center

Synchrotron radiation is a unique form of radiation that spans the electro-magnetic spectrum from X-rays through the ultraviolet and visible into the infrared. Tunable monochromators enable scientists to select a narrow band of wavelengths at any point in the spectrum. (Author/BB)

MOSAIC, 1978

1978-01-01

202

Electromagnetic radiation detector  

DOEpatents

An electromagnetic radiation detector including a collimating window, a cathode member having a photoelectric emissive material surface angularly disposed to said window whereby radiation is impinged thereon at acute angles, an anode, separated from the cathode member by an evacuated space, for collecting photoelectrons emitted from the emissive cathode surface, and a negatively biased, high transmissive grid disposed between the cathode member and anode.

Benson, Jay L. (Albuquerque, NM); Hansen, Gordon J. (Albuquerque, NM)

1976-01-01

203

Physics for Radiation Protection  

NASA Astrophysics Data System (ADS)

A practical guide to the basic physics that radiation protection professionals need A much-needed working resource for health physicists and other radiation protection professionals, this volume presents clear, thorough, up-to-date explanations of the basic physics necessary to address real-world problems in radiation protection. Designed for readers with limited as well as basic science backgrounds, Physics for Radiation Protection emphasizes applied concepts and carefully illustrates all topics through examples as well as practice problems. Physics for Radiation Protection draws substantially on current resource data available for health physics use, providing decay schemes and emission energies for approximately 100 of the most common radionuclides encountered by practitioners. Excerpts of the Chart of the Nuclides, activation cross sections, fission yields, fission-product chains, photon attenuation coefficients, and nuclear masses are also provided. Coverage includes: * The atom as an energy system * An overview of the major discoveries in radiation physics * Extensive discussion of radioactivity, including sources and materials * Nuclear interactions and processes of radiation dose * Calculational methods for radiation exposure, dose, and shielding * Nuclear fission and production of activation and fission products * Specialty topics ranging from nuclear criticality and applied statistics to X rays * Extensive and current resource data cross-referenced to standard compendiums * Extensive appendices and more than 400 figures

Martin, James E.

2000-06-01

204

Continuum radiation at Uranus  

Microsoft Academic Search

One Uranian radio emission which has thus far escaped attention is an analog of continuum radiation at earth, Jupiter, and Saturn. The emission is found to be propagating in the ordinary mode in the range of one to a few kHz on the inbound leg of the Voyager 2 encounter, shortly after the magnetopause crossing. The Uranian continuum radiation is

W. S. Kurth; D. A. Gurnett; M. D. Desch

1990-01-01

205

Radiation biology of mosquitoes  

Microsoft Academic Search

There is currently renewed interest in assessing the feasibility of the sterile insect technique (SIT) to control African malaria vectors in designated areas. The SIT relies on the sterilization of males before mass release, with sterilization currently being achieved through the use of ionizing radiation. This paper reviews previous work on radiation sterilization of Anopheles mosquitoes. In general, the pupal

Michelle EH Helinski; Andrew G Parker; Bart GJ Knols

2009-01-01

206

RADIATION POLYMERIZATION DOSIMETRY  

Microsoft Academic Search

Quantitative studies of the high energy radiation photo sensitivity of ; certain liquid monomer-polymers have indicated a possible solution to the problem ; of high level dosimetry. Investigations of the relation between absorbed dose ; and factors which influence sensitivity have led to the development of a ; dependable system of radiation polymerization dosimetry. Changes in the ; composition of

F. E. Hoecker; I. W. Watkins; J. T. Han

1958-01-01

207

Personal radiation dosimeter  

Microsoft Academic Search

A radiation dosimeter is described comprising: at least a first capacitive ionization chamber adapted to gradually discharge in the presence of incident radiation; a voltage source; a load resistor coupled to the voltage source; a first switch means coupled to the load resistor and the voltage source to form a first in-series circuit comprising the voltage source, the load resistor

Terhune

1986-01-01

208

Enhanced-Radiation Weapons  

Microsoft Academic Search

The enhanced-radiation warhead is a particularly dangerous weapon insofar as it might mislead anyone into believing that its deployment would make it possible for nuclear warfare to be safely limited and tightly controlled; in this sense its very deployment could lower the threshold separating conventional warfare from nuclear warfare. Enhanced-radiation weapons are no more (and perhaps they are less) ''humane''

Fred M. Kaplan

1978-01-01

209

Radiofrequency and microwave radiation  

Microsoft Academic Search

This paper deals with the controversy and disagreement surrounding the issue of harm from radiofrequency (RF) and microwaves. The radiation standards adopted by different countries are quite divergent with the least strict standard for microwave exposure differing from the most strict by a factor of 100. Among the most powerful sources of RF and microwave radiation are radar systems used

Hileman

1982-01-01

210

Radiation Damage Workshop  

SciTech Connect

The availability of data regarding the radiation behavior of GaAs and silicon solar cells is discussed as well as efforts to provide sufficient information. Other materials are considered too immature for reasonable radiation evaluation. The lack of concern over the possible catastrophic radiation degradation in cascade cells is a potentially serious problem. Lithium counterdoping shows potential for removing damage in irradiated P-type material, although initial efficiencies are not comparable to current state of the art. The possibility of refining the lithium doping method to maintain high initial efficiencies and combining it with radiation tolerant structures such as thin BSF cells or vertical junction cells could provide a substantial improvement in EOL efficiencies. Laser annealing of junctions, either those formed ion implantation or diffusion, may not only improve initial cell performance but might also reduce the radiation degradation rate.

Stella, P.M.

1984-01-01

211

Solar radiation in Jamaica  

SciTech Connect

Average monthly global radiation in Jamaica was calculated for the years between 1978 and 1987 from values measured at 12 stations and from Angstrom-coefficient derived values. From these values daily global radiation was estimated for various periods at grid points separated by approximately 10 km on a square. Three dimensional plots and contour maps for the various periods were produced. The interpolation was based on kriging adopted by Hay. A relationship between global and diffuse radiation based on the Liu and Jordan relationship was obtained. The errors in the interpolated annual values were less than 10%. The maps were made available to the public with suggested usages of solar energy. Diffuse radiation formed less than 50% of the total radiation.

Chen, A.A.; Chin, P.N.; Forrest, W.; McLean, P. (Univ. of the West Indies, Kingston (Jamaica)); Grey, C. (Meteorological Office, Kingston (Jamaica))

1994-11-01

212

Radiation Protection in Canada  

PubMed Central

The current status of radiation protection in Canada has been summarized in the present paper, the first of a three-part series. Particular emphasis has been placed on the role of the Radiation Protection Division of the Department of National Health and Welfare. Somatic and hereditary effects of radiation exposure are briefly discussed as a basis for an understanding of the radiation protection standards which have been developed at national and international levels. The rapid increase in use of radioactive materials and x-ray apparatus in medicine, industry and research, and the extensive atmosphere testing of nuclear weapons have led to the development of comprehensive radiation protection activities in Canada, especially in the Department of National Health and Welfare. Well-established lines of communication and liaison exist among the various agencies responsible for these activities. ImagesFig. 1

Bird, P. M.

1964-01-01

213

Fundamentals of Radiation Dosimetry  

SciTech Connect

The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

Bos, Adrie J. J. [Delft University of Technology, Faculty of Applied Sciences, Mekelweg 15, 2629JB Delft (Netherlands)

2011-05-05

214

Fundamentals of Radiation Dosimetry  

NASA Astrophysics Data System (ADS)

The basic concepts of radiation dosimetry are reviewed on basis of ICRU reports and text books. The radiation field is described with, among others, the particle fluence. Cross sections for indirectly ionizing radiation are defined and indicated is how they are related to the mass energy transfer and mass energy absorption coefficients. Definitions of total and restricted mass stopping powers of directly ionizing radiation are given. The dosimetric quantities, kerma, absorbed dose and exposure together with the relations between them are discussed in depth. Finally it is indicated how the absorbed dose can be measured with a calorimeter by measuring the temperature increase and with an ionisation chamber measuring the charge produced by the ionizing radiation and making use of the Bragg-Gray relation.

Bos, Adrie J. J.

2011-05-01

215

Dangers of Radiation Exposure  

NSDL National Science Digital Library

In the first part of the lesson, students calculate their yearly exposure rate to harmful high-energy radiation and cumulative effects over time. They then use the information to evaluate the various sources of radiation that are of greatest concern for them. In the second part of the lesson, students learn that spacecraft and other objects in space must be concerned with the same kinds of radiation to which humans are exposed. The MESSENGER spacecraft will orbit Mercury and be subjected to much more intense solar radiation than it would near Earth. Students discuss the notion that even though some of the radiation is needed to study the properties of the planet, too much of it can be quite damaging.

American Association for the Advancement of Science (AAAS;)

2005-03-15

216

Radiation and health*  

PubMed Central

Radiation has been a source of fascination and concern ever since Wilhelm Konrad Rntgen discovered X-rays on 8 November 1895. Over the years, health workers as well as the public have been concerned about medical uses of X-rays, the presence of radon in buildings, radioactive waste from nuclear power stations, fallout from nuclear test explosions, radioactive consumer products, microwave ovens, and many other sources of radiation. Most recently, the tragic accident at the Chernobyl nuclear power station in the USSR, and the subsequent contamination over most of Europe, has again wakened interest and concern and also reminded us about a number of misconceptions about radiation. This article describes the essentials about radiation (especially ionizing radiation) and its health effects.

Lindell, B.

1987-01-01

217

Chitosan and radiation chemistry  

NASA Astrophysics Data System (ADS)

Chitosan as a raw material with special properties has drawn attention of scientists working in the field of radiation processing and natural polymer products development, and also of specialists working in the field of radiation protection and oncologists. Especially the applications concern reduced molecular weight chitosan which still retain its chemical structure; such form of the compound is fostering biological, physical and chemical reactivity of the product. Chitosan degrades into fragments under ?-ray or electron beam irradiation. Antibacterial properties of the product are applied in manufacturing hydrogel for wound dressing and additional healing properties can be achieved by incorporating in the hydrogel matrix chitosan bonded silver clusters. Another possible application of chitosan is in reducing radiation damage to the radiation workers or radiation cured patients. In the case of radioisotopes oral or respiratory chitosan-based materials can be applied as chelators. Applications of chitosan in oncology are also reported.

Chmielewski, Andrzej G.

2010-03-01

218

Radiation heat loss detector  

SciTech Connect

In a radiation heat loss detector, radiation from an extended surface area is detected with a sensor having a wide field of view closely matching that of an associated camera. By simultaneously photographing the surface area of interest and detecting the radiation from that same area, a clear record is provided for future use. A wide band radiation sensor is used. Compensation for environmental radiation is made by first viewing the environment with the sensor and holding the sensed signal and then subtracting that signal from the flux detected when the sensor faces the extended surface area. The date and time are also recorded on the photograph. A sonar device positioned on the camera provides a distance indication which, with a known field of view, allows for a determination of the total flux from the surface area, a determination of convective heat losses from the surface and a correction for atmospheric absorption of the radiant energy.

Pompei, F.

1982-08-10

219

Radiation resistance of radiation shield rubber.  

National Technical Information Service (NTIS)

The radiation shield rubber of ethylene-propylene copolymer (EPDM) and of chlorinated polyethylene (CM) mixed with a large amount of powder or foil lead were irradiated under vacuum or in oxygen atmosphere by Co-60 gamma rays for an evaluation of the radi...

A. Kasai N. Yamaguchi T. Watanabe T. Seguchi M. Nishii

1990-01-01

220

RADIATION BIOLOGY: CONCEPTS FOR RADIATION PROTECTION  

Microsoft Academic Search

The opportunity to write a historical review of the field of radiation biology allows for the viewing of the devel- opment and maturity of a field of study, thereby being able to provide the appropriate context for the earlier years of re- search and its findings. The pioneering work of Muller, Sax, and McClintock, and many others, has stood the

R. Julian Preston

2004-01-01

221

Radiation Therapy for Lung Cancer  

MedlinePLUS

... visit: National Cancer Institute www.cancer.gov/clinicaltrials Radiation Therapy Answers www.rtanswers.org STRO AMERICAN SOCIETY FOR ... of the lung cancer and your overall health. Radiation Therapy Radiation is a high-energy X-ray that ...

222

Radiation Therapy: Additional Treatment Options  

MedlinePLUS

... Prostate Skin Upper GI Latest Research Find a Radiation Oncologist Last Name: Facility: City: State: Zip Code: ... infections. This is refered to as immunotherapy . Intraoperative Radiation Therapy Radiation therapy given during surgery is called ...

223

Synchrotron radiation sources and research  

SciTech Connect

This is an introduction and a review of Synchrotron Radiation sources and the research performed using synchrotron radiation. I will begin with a brief discussion of the two principal uses of particle storage rings: for colliding beams (Collider) and for synchrotron radiation (Radiator). Then I will concentrate on discussions of synchrotron radiation topics, starting with a historical account, followed by descriptions of the features of the storage ring and the features of the radiation from the simplest source -- the bending magnet. I will then discuss the special insertion device sources -- wigglers and undulators -- and their radiations, and end with a brief general account of the research and other applications of synchrotron radiation.

Teng, L.C.

1995-12-31

224

Modifying Radiation Damage  

PubMed Central

Radiation leaves a fairly characteristic footprint in biological materials, but this is rapidly all but obliterated by the canonical biological responses to the radiation damage. The innate immune recognition systems that sense danger through direct radiation damage and through associated collateral damage set in motion a chain of events that, in a tissue compromised by radiation, often unwittingly result in oscillating waves of molecular and cellular responses as tissues attempt to heal. Understanding natures whispers that inform on these processes will lead to novel forms of intervention targeted more precisely towards modifying them in an appropriate and timely fashion so as to improve the healing process and prevent or mitigate the development of acute and late effects of normal tissue radiation damage, whether it be accidental, as a result of a terrorist incident, or of therapeutic treatment of cancer. Here we attempt to discuss some of the non-free radical scavenging mechanisms that modify radiation responses and comment on where we see them within a conceptual framework of an evolving radiation-induced lesion.

Kim, Kwanghee; McBride, William H.

2011-01-01

225

Microenvironment and Radiation Therapy  

PubMed Central

Dependency on tumor oxygenation is one of the major features of radiation therapy and this has led many radiation biologists and oncologists to focus on tumor hypoxia. The first approach to overcome tumor hypoxia was to improve tumor oxygenation by increasing oxygen delivery and a subsequent approach was the use of radiosensitizers in combination with radiation therapy. Clinical use of some of these approaches was promising, but they are not widely used due to several limitations. Hypoxia-inducible factor 1 (HIF-1) is a transcription factor that is activated by hypoxia and induces the expression of various genes related to the adaptation of cellular metabolism to hypoxia, invasion and metastasis of cancer cells and angiogenesis, and so forth. HIF-1 is a potent target to enhance the therapeutic effects of radiation therapy. Another approach is antiangiogenic therapy. The combination with radiation therapy is promising, but several factors including surrogate markers, timing and duration, and so forth have to be optimized before introducing it into clinics. In this review, we examined how the tumor microenvironment influences the effects of radiation and how we can enhance the antitumor effects of radiation therapy by modifying the tumor microenvironment.

Yoshimura, Michio; Itasaka, Satoshi; Harada, Hiroshi; Hiraoka, Masahiro

2013-01-01

226

Beneficial uses of radiation  

SciTech Connect

An overall decline in technical literacy within the American public has come at a time when technological advances are accelerating in the United States and around the world. This had led to a large communication gulf between the general public and the technologists. Nowhere is this more evident then with the topic of radiation. Regrettably, too few people know about sources of radiation, the pervasiveness, amounts, and variabilities, and do not have a true understanding of the environment in which we live. Nor do many people know that radiation has been used in beneficial ways for decades around the world. While the general public does not know of the scientific applications to which radiation has been deployed, it nevertheless had benefited tremendously from these efforts. Thanks to the well know properties of radiation, scientific ingenuity has found many uses of radiation in chemical and agricultural research, biomedical research, in the diagnoses and treatment of hundreds of types of diseases, in industrial applications, food irradiation, and many others. This paper provides a sample of the types of uses to which radiation has been used to help advance the betterment of humankind.

Fox, M.R.

1991-10-01

227

Modifying radiation damage.  

PubMed

Radiation leaves a fairly characteristic footprint in biological materials, but this is rapidly all but obliterated by the canonical biological responses to the radiation damage. The innate immune recognition systems that sense "danger" through direct radiation damage and through associated collateral damage set in motion a chain of events that, in a tissue compromised by radiation, often unwittingly result in oscillating waves of molecular and cellular responses as tissues attempt to heal. Understanding "nature's whispers" that inform on these processes will lead to novel forms of intervention targeted more precisely towards modifying them in an appropriate and timely fashion so as to improve the healing process and prevent or mitigate the development of acute and late effects of normal tissue radiation damage, whether it be accidental, as a result of a terrorist incident, or of therapeutic treatment of cancer. Here we attempt to discuss some of the non-free radical scavenging mechanisms that modify radiation responses and comment on where we see them within a conceptual framework of an evolving radiation-induced lesion. PMID:20583981

Kim, Kwanghee; McBride, William H

2010-11-01

228

SYNCHROTRON RADIATION SOURCES  

SciTech Connect

Synchrotron radiation is a very bright, broadband, polarized, pulsed source of light extending from the infrared to the x-ray region. It is an extremely important source of Vacuum Ultraviolet radiation. Brightness is defined as flux per unit area per unit solid angle and is normally a more important quantity than flux alone particularly in throughput limited applications which include those in which monochromators are used. It is well known from classical theory of electricity and magnetism that accelerating charges emit electromagnetic radiation. In the case of synchrotron radiation, relativistic electrons are accelerated in a circular orbit and emit electromagnetic radiation in a broad spectral range. The visible portion of this spectrum was first observed on April 24, 1947 at General Electric's Schenectady facility by Floyd Haber, a machinist working with the synchrotron team, although the first theoretical predictions were by Lienard in the latter part of the 1800's. An excellent early history with references was presented by Blewett and a history covering the development of the utilization of synchrotron radiation was presented by Hartman. Synchrotron radiation covers the entire electromagnetic spectrum from the infrared region through the visible, ultraviolet, and into the x-ray region up to energies of many 10's of kilovolts. If the charged particles are of low mass, such as electrons, and if they are traveling relativistically, the emitted radiation is very intense and highly collimated, with opening angles of the order of 1 milliradian. In electron storage rings there are three possible sources of synchrotron radiation; dipole (bending) magnets; wigglers, which act like a sequence of bending magnets with alternating polarities; and undulators, which are also multi-period alternating magnet systems but in which the beam deflections are small resulting in coherent interference of the emitted light.

HULBERT,S.L.; WILLIAMS,G.P.

1998-07-01

229

Radiation Damage Theory  

SciTech Connect

This chapter presents an overview of basic radiation damage theory, including older and more recent models, to provide framework, within which radiation effects, such as void swelling, can be rationalized. A complete review of the literature is not attempted, but sufficient references are given to provide a decent introduction to a quite large number of publications in the field. Many derivations are different from and, in our view, more elegant than in the original publications. The work is directed to both theoreticians and experimentalists, and, especially, to those passionate individuals who are going to take the radiation damage theory (RDT) to the future.

Golubov, Stanislav I [ORNL; Barashev, Aleksandr [University of Liverpool; Stoller, Roger E [ORNL

2012-01-01

230

METHOD FOR MEASURING RADIATION  

DOEpatents

A method for measuring an unknown integrated quantity of radiation with a condenser ionization chamber is described. The chamber is initially charged to a predetermined voltage by a voltage source. The chamber is then removed from the source and exposed to an unknown quantity of radiation for a period of time. The quantity of radiation to which the chamber was exposed is then measured by detecting the magnitude of the pulse of current necessary to recharge the chamber of its initial value through a suitable impedance. The current pulse is amplified and measured directly by a suitable pulse height analyzing system. (AEC)

Roesch, W.C.; McCall, R.C.

1961-11-21

231

Galactic Positron Annihilation Radiation  

NASA Astrophysics Data System (ADS)

Nine years of observations with the CGRO/OSSE instrument have allowed the first maps of positron annihilation radiation. The extraction of annihilation radiation from a complex spectrum composed of both compact and diffuse sources depends upon the unique spectral signatures of 511 keV line and positronium continuum emissions. We report here results of a re-analysis of OSSE obtained spectra of the galactic center region. We show updated maps of annihilation radiation, and discuss how these maps influence the interpretation of suggested sources of galactic positrons.

Milne, P. A.; Kurfess, J. D.; Strickman, M. S.; Leising, M. D.

2002-05-01

232

Absolute radiation detector  

NASA Astrophysics Data System (ADS)

An absolute radiation detector (a cryogenic radiometer) is being developed to replace the existing UK primary national standard cryogenic radiometer with an improved uncertainty. The cryogenic radiometer will be capable of measuring black body radiation and laser radiation with an uncertainty approaching 10 ppm. From these measurements it will be possible to determine the fundamental constant, the Stefan Boltzmann constant, confirming the radiometer as an absolute detector, and link this determination to the SI unit of luminous intensity, the candela. Thus detector and source based scales/standards will be tied to an invariant physical quantity ensuring their long-term stability.

Martin, John E.

1996-11-01

233

Composition for radiation shielding  

DOEpatents

A composition for use as a radiation shield. The shield has a depleted urum core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container.

Kronberg, James W. (Aiken, SC)

1994-01-01

234

Radiation degradation of polymethacrylamide  

SciTech Connect

The effects of radiation on polymers have been studied for many years. When polymers are subjected to ultraviolet light or ionizing radiation, chain scission and crosslinking are possible. The radiation degradations of several methacrylate type polymers were investigated. The primary polymer studied was polymethacrylamide (PMAAm). Ultraviolet irradiated PMAAm yielded a five line ESR spectrum with 22 gauss splitting which is believed to arise from a polymeric radical ending with a methacrylamide unit. The results obtained indicate that polymethacrylamide is a polymer which undergoes main chain cleavage upon irradiation. As such this polymer may have potential applicability as a positive resist for fabrication of microelectronic devices.

O'Connor, D.J.

1984-01-01

235

Fast multilevel radiative transfer  

NASA Astrophysics Data System (ADS)

The vast majority of recent advances in the field of numerical radiative transfer relies on approximate operator methods better known in astrophysics as Accelerated Lambda-Iteration (ALI). A superior class of iterative schemes, in term of rates of convergence, such as Gauss-Seidel and Successive Overrelaxation methods were therefore quite naturally introduced in the field of radiative transfer by Trujillo Bueno & Fabiani Bendicho (1995); it was thoroughly described for the non-LTE two-level atom case. We describe hereafter in details how such methods can be generalized when dealing with non-LTE unpolarised radiation transfer with multilevel atomic models, in monodimensional geometry.

Paletou, Frdric; Lger, Ludovick

2007-01-01

236

Clouds and Solar Radiation  

NSDL National Science Digital Library

Most people are aware that clouds impact the amount of solar energy that is received at the ground. This lesson examines qualitative and quantitative aspects of how clouds affect incoming solar radiation. Students will be given a visible satellite image, and asked to describe where clouds are located in the state. Given a map of Mesonet solar radiation measurements, the students will be asked to determine regions of relatively high and low values of solar radiation. This lesson also enables students to practice analyzing different types of data sets and compare patterns between two types of data.

237

Blackbody Radiation Spectrum Model  

NSDL National Science Digital Library

The Blackbody Radiation Spectrum model shows six fixed-temperature curves between Tmin and Tmax and a red variable-temperature curve that can be adjusted using a slider. The wavelength is measured in nm (nanometer) and the intensity is measured in W.e-5 / (m2.nm). Users can adjust Tmin and Tmax to change the temperature range that is displayed. The Blackbody Radiation Spectrum was created using the Easy Java Simulations (Ejs) modeling tool. It is distributed as a ready-to-run (compiled) Java archive. Double click the ejs_ntnu_BlackbodyRadiationSpectrum.jar file to run the program if Java is installed.

Hwang, Fu-Kwun

2009-08-22

238

Radiation Safety System  

SciTech Connect

The goal of this work is to provide an overview of a Radiation safety system (RSS) designed for protection from prompt radiation hazard at accelerator facilities. RSS design parameters, functional requirements and constraints are derived from hazard analysis and risk assessment undertaken in the design phase of the facility. The two main subsystems of a RSS are access control system (ACS) and radiation control system (RCS). In this text, a common approach to risk assessment, typical components of ACS and RCS, desirable features and general design principles applied to RSS are described.

Vylet, Vaclav; /Jefferson Lab; Liu, James C.; /SLAC; Walker, Lawrence S.; /Los Alamos

2012-04-04

239

Radiation and Health  

NASA Astrophysics Data System (ADS)

This is a shortened version of the Science Teachers' Workshop offered free of charge to primary and secondary teachers at a location of their choice, covering fundamentals of nuclear radiation, natural and man-made sources of radiation, biological effects and risks to health, radioactive waste management, and radiation safety management and regulation. The course includes a hands-on demonstration of use of Geiger Counters, which are given without cost to participants for use in their classes. A CD and notebook of class material are issued to each student. Lunch will be provided. Limited to 20 participants.

Evans, Albert E.

2008-03-01

240

Radiation and Health  

NASA Astrophysics Data System (ADS)

This is a shortened version of the Science Teachers' Workshop offered free of charge to primary and secondary teachers at a location of their choice, covering fundamentals of nuclear radiation, natural and man-made sources of radiation, biological effects and risks to health, radioactive waste management, and radiation safety management and regulation. The course includes a hands-on demonstration of use of Geiger Counters, which are given without cost to participants for use in their classes. A CD and notebook of class material are issued to each student. Lunch will be provided.

Evans, Albert; Blanchard, Karen

2007-10-01

241

Method of enhancing radiation response of radiation detection materials  

DOEpatents

The present invention is a method of increasing radiation response of a radiation detection material for a given radiation signal by first pressurizing the radiation detection material. Pressurization may be accomplished by any means including mechanical and/or hydraulic. In this application, the term "pressure" includes fluid pressure and/or mechanical stress.

Miller, Steven D. (Richland, WA)

1997-01-01

242

Effect of radiation dose on radiation creep of polymers  

Microsoft Academic Search

In investigations of radiation creep and service life of polymers the question arises: Are these radiation effects not determined by increasing doses of ionizing radiation? The effect of a radiation dose may be manifested, in particular, in rupture of the chemical bonds responsible for the strength of the polymer, as loading might cause supplemental deformation; and, when irradiation takes place

V. F. Stepanov; S. . Vaisberg; V. L. Karpov

1974-01-01

243

Ultraviolet radiation in the rhne river lenses of low salinity and in marine waters of the northwestern mediterranean sea: attenuation and effects on bacterial activities and net community production.  

PubMed

The high content in nutrients of freshwater outflows induces highly productive and buoyant plumes spreading over marine waters (MW). As a consequence, the growth of organisms developing in these low-salinity waters (LSW) might be potentially affected by UV-R (280-400 nm). This study investigated the penetration of UV-R and its impact on net community production (NCP) and bacterial protein (B(PROT)S) and DNA (B(DNA)S) synthesis in mesotrophic-LSW formed from the Rhne River and in oligotrophic MW of the Northwestern Mediterranean Sea (Gulf of Lions) in May 2006. High concentrations of chlorophyll a (up to 8 microg L(-1)) measured in the LSW (<37.8 psu, 0-10 m) were the main factor influencing the diffuse attenuation coefficients (K(d)) of both UV-R and photosynthetically active radiation (PAR). The mean ratio of the K(d) measured between the LSW and the MW increased with wavelength from 2.4 at 305 nm to 2.9 at 380 nm and 3.1 for PAR indicating more similarity in the UV region. NCP was severely inhibited by UV-R at the surface of the LSW, whereas no effect was measured in the surrounding MW. In contrast, B(PROT)S and B(DNA)S were affected deeper by UV-R in the MW (up to 8 m depth) compared to the LSW where inhibition was only observed at the surface. Differences in response of bacteria in LSW and MW are largely explained by differences in UV-R transparency; however, transplant experiments indicate that bacterial assemblages from the MW were also more sensitive to UV-R than those present in the LSW. We also observed that higher activity of bacteria after nutrient additions increased their sensitivity to UV-R during the day, but favored their recovery during the night incubation period for both LSW and MW. Results suggest that riverine and nutrient inputs may alter the effects of UV-R on microbial activity by attenuating the UV-R penetration and by modifying the physiology of bacteria. PMID:19067946

Joux, Fabien; Jeffrey, Wade H; Abboudi, Maher; Neveux, Jacques; Pujo-Pay, Mireille; Oriol, Louise; Naudin, Jean-Jacques

2008-11-19

244

Radiation Exposure and Cancer  

MedlinePLUS

... such actions are warranted, according to the NIEHS. Television and computer screens Modern television and computer screens give off several kinds of ... waves) Radiofrequency radiation is emitted from radio and television broadcast transmitters, citizen band radios, and electric heaters. ...

245

External Radiation Therapy  

MedlinePLUS Videos and Cool Tools

... mark where the differences between success rates with radical prostatectomy and radiation therapy become evident,and if you' ... to put you through a major operation like radical prostatectomy, and in those situations, I do refer patients ...

246

Amorphous silicon radiation detectors  

DOEpatents

Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification. 13 figs.

Street, R.A.; Perez-Mendez, V.; Kaplan, S.N.

1992-11-17

247

Management of radiation wounds  

SciTech Connect

Radiation wounds caused by newer high-voltage radiotherapy techniques are very difficult to manage. Recent developments in flap design and transfer aid the surgeon in successfully treating these difficult problems.

Reinisch, J.F.; Puckett, C.L.

1984-08-01

248

Hyperphysics: Blackbody Radiation  

NSDL National Science Digital Library

This Hyperphysics site gives a thorough explanation of "Blackbody" or "cavity" radiation, offering examples on both the classical and quantum level. A number of diagrams and example plots are used to aid in the description.

Nave, Carl R.

2008-07-18

249

Radiation Hardened Field Oxide.  

National Technical Information Service (NTIS)

This paper describes the development of a radiation-tolerant field oxide compatible with both MOS and bipolar technologies. Data is presented which illustrates that nonguardbanded devices utilizing conventional field oxide structures cannot be expected to...

J. R. Adams W. R. Dawes T. J. Sanders

1977-01-01

250

Radiation Technology, Issue 6.  

National Technical Information Service (NTIS)

The publication deals with theoretical and experimental works on the nuclear-physical basis of radiation technology, isotope thermoelectric generators, equipment irradiation, pulse proton generator, nuclear methods of analysis, gamma flaw detection, radio...

1971-01-01

251

Synchrotron Radiation Sources  

ScienceCinema

The fundamental basis of synchrotron radiation will be presented in an easy to follow historically based perspective. The development of modern high brightness sources will be illustrated and a view given of the potential for coherent sources in the future.

252

[Genetic effects of radiation].  

PubMed

This paper is a short review of genetic effect of radiation. This includes methods and results of a large-scale genetic study on specific loci in mice and of various studies in the offspring of atomic-bomb survivors. As for the latter, there is no results obtained which suggest the effect of parental exposure to radiation. Further, in recent years, studies are conducted to the offspring born to parents who were survivors of childhood cancers. In several reports, the mean gonad dose is quite large whereas in most instances, the results do not indicate genetic effect following parental exposure to radiation. Possible reasons for the difficulties in detecting genetic effect of radiation are discussed. PMID:22514926

Nakamura, Nori

2012-03-01

253

IMPULSE RADIATING ANTENNAS  

Microsoft Academic Search

A number of applications require radiation of a short pulse of electromagnetic energy out to large distances. These applications include target discrimination in a cluttered environment (e.g., looking over the ocean), aircraft identification by taking a \\

Carl E. Baum; Everett G. Farr; Kirtland AFB

254

Radiation risks in pregnancy  

SciTech Connect

A major contraindication of radiodiagnostic procedures is pregnancy. Approximately 1% of all pregnant women are given abdominal x-rays during the first trimester of pregnancy. Evaluation of radiation exposure should involve consideration of the types of examinations performed and when performed, as well as radiation dose and risk estimation. This information is then weighed against other possible risks of the pregnancy as well as personal factors. In the authors' experiences, radiation exposures usually result in doses to the embryo of less than 5 cGy (rad); the resulting radiation risks are usually small compared with other risks of pregnancy. Procedures to minimize diagnostic x-ray exposure of the fetus are also discussed.

Mossman, K.L.; Hill, L.T.

1982-08-01

255

John Tyndall's Radiation Experiment  

Microsoft Academic Search

IN the recently published ``Life and Work of John Tyndall'' no alteration has been made in his explanation of his experiment on radiation through a solution of iodine in carbon disulphide, rendering platinized platinum foil white hot.

T. H. Muras

1946-01-01

256

Calculate Your Radiation Dose  

MedlinePLUS

... Do you live within 50 miles of a nuclear power plant? Do you live within 50 miles of a coal fired power plant? TOTAL YEARLY DOSE (in mrem) ... the American Nuclear Society's brochure, "Personal Radiation Dose Chart". The primary ...

257

Radiation and Society  

ERIC Educational Resources Information Center

Presents a discussion of the risks, to society, from radiation-associated technologies and urges that science teachers help the public understand the decision-making process relative to nuclear power as well as the problems and alternatives. (PEB)

Shaw, Edward I.

1974-01-01

258

Tin Can Radiation Detector.  

ERIC Educational Resources Information Center

Provides instructions for making tin can radiation detectors from empty aluminum cans, aluminum foil, clear plastic, copper wire, silica gel, and fine, unwaxed dental floss put together with tape or glue. Also provides suggestions for activities using the detectors. (JN)

Crull, John L.

1986-01-01

259

Amorphous silicon radiation detectors  

DOEpatents

Hydrogenated amorphous silicon radiation detector devices having enhanced signal are disclosed. Specifically provided are transversely oriented electrode layers and layered detector configurations of amorphous silicon, the structure of which allow high electric fields upon application of a bias thereby beneficially resulting in a reduction in noise from contact injection and an increase in signal including avalanche multiplication and gain of the signal produced by incoming high energy radiation. These enhanced radiation sensitive devices can be used as measuring and detection means for visible light, low energy photons and high energy ionizing particles such as electrons, x-rays, alpha particles, beta particles and gamma radiation. Particular utility of the device is disclosed for precision powder crystallography and biological identification.

Street, Robert A. (Palo Alto, CA); Perez-Mendez, Victor (Berkeley, CA); Kaplan, Selig N. (El Cerrito, CA)

1992-01-01

260

Solar Cell Radiation Handbook.  

National Technical Information Service (NTIS)

The handbook to predict the degradation of solar cell electrical performance in any given space radiation environment is presented. Solar cell theory, cell manufacturing and how they are modeled mathematically are described. The interaction of energetic c...

B. E. Anspaugh H. Y. Tada J. R. Carter R. G. Downing

1982-01-01

261

Isotopes and radiation  

SciTech Connect

Subjects covered in this section are: (1) Food industry groups petition for expanded use of irradiation; (2) First meeting of BEIR VII committee with new members held; and (3) DOE undertaking 10-yr study of radiation health effects.

NONE

1999-10-01

262

Stellar Blackbody Radiation Curves  

NSDL National Science Digital Library

Stellar Blackbody Radiation Curves model simulates the blackbody radiation curve of stars and how this leads to the observed color and luminosity of the star. If a star can be treated as a blackbody, the blackbody radiation curve of the star, the power density per area (or intensity) per wavelength (energy/time/volume) vs wavelength, is dependent on the star's temperature (spectral class). In the simulation, the star is shown along with its luminosity and spectral class. In separate graph, the blackbody radiation curve, the visible part of the spectrum, and the integrated stellar surface intensity (integrating the blackbody curve over all wavelengths) are shown. In another window the HR diagram can be shown indicating the current star's parameters. The radius of the star (in Rsun) and the temperature of the star in Kelvin (5780 K is Tsun) can be changed.

Belloni, Mario

2010-11-11

263

Ionizing radiation detector  

DOEpatents

An ionizing radiation detector is provided which is based on the principal of analog electronic integration of radiation sensor currents in the sub-pico to nano ampere range between fixed voltage switching thresholds with automatic voltage reversal each time the appropriate threshold is reached. The thresholds are provided by a first NAND gate Schmitt trigger which is coupled with a second NAND gate Schmitt trigger operating in an alternate switching state from the first gate to turn either a visible or audible indicating device on and off in response to the gate switching rate which is indicative of the level of radiation being sensed. The detector can be configured as a small, personal radiation dosimeter which is simple to operate and responsive over a dynamic range of at least 0.01 to 1000 R/hr.

Thacker, L.H.

1989-06-08

264

SOLAR RADIATION, VA  

EPA Science Inventory

Sterling, Virginia Integrated Surface Irradiance Study (ISIS) solar radiation data files from National Oceanic and Atmospheric Administration (NOAA), zipped from ftp://ftp.atdd.noaa.gov/pub/projects/isis/ste/monthly...

265

Acute radiation syndrome caused by accidental radiation exposure - therapeutic principles  

PubMed Central

Fortunately radiation accidents are infrequent occurrences, but since they have the potential of large scale events like the nuclear accidents of Chernobyl and Fukushima, preparatory planning of the medical management of radiation accident victims is very important. Radiation accidents can result in different types of radiation exposure for which the diagnostic and therapeutic measures, as well as the outcomes, differ. The clinical course of acute radiation syndrome depends on the absorbed radiation dose and its distribution. Multi-organ-involvement and multi-organ-failure need be taken into account. The most vulnerable organ system to radiation exposure is the hematopoietic system. In addition to hematopoietic syndrome, radiation induced damage to the skin plays an important role in diagnostics and the treatment of radiation accident victims. The most important therapeutic principles with special reference to hematopoietic syndrome and cutaneous radiation syndrome are reviewed.

2011-01-01

266

Radiation hard fiber optics  

Microsoft Academic Search

A study of radiation-inducted absorption in low-loss optical waveguides is reported. Step-index optical fibers were prepared from preforms fabricated by the CVD method. The germanium silicate core glass in the fibers was doped with varying amounts of antimony, cerium, boron, phosphorus and hydroxyl groups. The effects of such variations in the glass chemistry on the radiation inducted attenuation of the

R. E. Jaeger; M. Aslami

1981-01-01

267

Pelvic Radiation in Women  

Microsoft Academic Search

\\u000a Pelvic radiation represents a major therapeutic strategy, either as adjuvant or primary treatment in the management of cancer\\u000a in women. This mainly concerns women with gynaecological malignancies: endometrial, cervical, vaginal, and vulva cancer; intestinal\\u000a malignancies: rectal and anal cancer, and bladder cancer. Further, long-term breast cancer survivors may experience similar\\u000a adverse effects after ovarian ablation accomplished by pelvic radiation. Finally,

Pernille T. Jensen

268

Radiative Transitions in Charmonium  

SciTech Connect

The form factors for the radiative transitions between charmonium mesons are investigated. We employ an anisotropic lattice using a Wilson gauge action, and domain-wall fermion action. We extrapolate the form factors to Q{sup 2} = 0, corresponding to a real photon, using quark-model-inspired functions. Finally, comparison is made with photocouplings extracted from the measured radiative widths, where known. Our preliminary results find photocouplings commensurate with these experimentally extracted values.

Jozef Dudek; Robert Edwards; David Richards

2005-10-01

269

Nanocomposites for radiation sensing  

NASA Astrophysics Data System (ADS)

The use of light emitting nanoparticles in polymer and glass matrices was studied for the detection of radiation. These nanocomposite scintillators were produced by various approaches including quantum dot/polymer, fluoride nanophosphor/epoxy and halide nanophosphor containing glass-ceramic composites. The synthesis and characterization of these nanoparticles as well as their incorporation into composites is discussed. Further, the application of these composites for radiation detection and spectroscopy is described.

Wagner, Brent K.; Kang, Zhitao; Nadler, Jason; Rosson, Robert; Kahn, Bernd

2012-05-01

270

Radiation Color Plot  

NSDL National Science Digital Library

Energy from the sun reaches the Earth and some is absorbed by the air, land, and water. Some of the energy is reflected back into space, meaning it does not heat the land, air, or water. In this lesson students will read a color plot of Earth's absorption of the sun's radiation. They will evaluate causes for difference in absorption rates at different points around the world and draw conclusions about factors effecting absorption of sun's radiation.

271

Net Radiation and Temperature  

NSDL National Science Digital Library

In this activity, students analyze actual net radiation data from their professor's field site in Northern Manitoba, Canada. They use this data to assess when the site has a radiation surplus and when it has a deficit. They use this data to estimate the time of the temperature minimum. They then think about what they've learned about seasonal cycles in insolation to predict how these patterns would shift at a different time of year.

Dunn, Allison

272

Smart radiation sensor management  

Microsoft Academic Search

We developed two radiation mapping algorithms that can handle different situations based on prior information of the search area. The algorithms were developed in the framework of model-driven measurement, where a world model was used to drive measurement collection, and measurements were used to update the world model.We developed and experimentally tested a robotic implementation of two Bayesian-based radiation mapping

R. ANDRES CORTEZ; Xanthi Papageorgiou; HERBERT G. TANNER; ALEXEI V. KLIMENKO; KONSTANTIN N. BOROZDIN; Ron Lumia; WILLIAM C. PRIEDHORSKY

2008-01-01

273

Automated personnel radiation monitor  

Microsoft Academic Search

An automated Personnel Low-Level Radiation Portal Monitor has been developed by UNC Nuclear Industries, Inc. It is micro-computer controlled and uses nineteen large gas flow radiation detectors. By employing a micro-computer, sophisticated mathematical analysis is used on the detector informational data base to determine the statistical probability of contamination. This system provides for: (1) Increased sensitivity to point source contamination;

1981-01-01

274

Gene Therapy and Radiation  

Microsoft Academic Search

\\u000a Owing to a low efficiency of gene transfer when delivered systemically, gene therapy may find its greatest utility in the\\u000a clinic when combined with loco-regional cancer treatment such as radiation therapy. Although a variety of gene therapy strategies\\u000a have been combined with radiation in preclinical models, only a handful have been translated into the clinic. Overall, combining\\u000a gene therapy with

Svend O. Freytag; Kenneth N. Barton; Farzan Siddiqui; Mohamed Elshaikh; Hans Stricker; Benjamin Movsas

275

ISO radiation sterilization standards  

NASA Astrophysics Data System (ADS)

This presentation provides an overview of the current status of the ISO radiation sterilization standards. The ISO standards are voluntary standards which detail both the validation and routine control of the sterilization process. ISO 11137 was approved in 1994 and published in 1995. When reviewing the standard you will note that less than 20% of the standard is devoted to requirements and the remainder is guidance on how to comply with the requirements. Future standards developments in radiation sterilization are being focused on providing additional guidance. The guidance that is currently provided in informative annexes of ISO 11137 includes: device/packaging materials, dose setting methods, and dosimeters and dose measurement, currently, there are four Technical Reports being developed to provide additional guidance: 1. AAMI Draft TIR, ``Radiation Sterilization Material Qualification'' 2. ISO TR 13409-1996, ``Sterilization of health care products - Radiation sterilization - Substantiation of 25 kGy as a sterilization dose for small or infrequent production batches'' 3. ISO Draft TR, ``Sterilization of health care products - Radiation sterilization Selection of a sterilization dose for a single production batch'' 4. ISO Draft TR, ``Sterilization of health care products - Radiation sterilization-Product Families, Plans for Sampling and Frequency of Dose Audits.''

Lambert, Byron J.; Hansen, Joyce M.

1998-06-01

276

Radiation disasters and children.  

PubMed

The special medical needs of children make it essential that pediatricians be prepared for radiation disasters, including 1) the detonation of a nuclear weapon; 2) a nuclear power plant event that unleashes a radioactive cloud; and 3) the dispersal of radionuclides by conventional explosive or the crash of a transport vehicle. Any of these events could occur unintentionally or as an act of terrorism. Nuclear facilities (eg, power plants, fuel processing centers, and food irradiation facilities) are often located in highly populated areas, and as they age, the risk of mechanical failure increases. The short- and long-term consequences of a radiation disaster are significantly greater in children for several reasons. First, children have a disproportionately higher minute ventilation, leading to greater internal exposure to radioactive gases. Children have a significantly greater risk of developing cancer even when they are exposed to radiation in utero. Finally, children and the parents of young children are more likely than are adults to develop enduring psychologic injury after a radiation disaster. The pediatrician has a critical role in planning for radiation disasters. For example, potassium iodide is of proven value for thyroid protection but must be given before or soon after exposure to radioiodines, requiring its placement in homes, schools, and child care centers. Pediatricians should work with public health authorities to ensure that children receive full consideration in local planning for a radiation disaster. PMID:12777572

2003-06-01

277

Fabric space radiators  

SciTech Connect

Future Air Force space missions will require thermal radiators that both survive in the hostile space environment and stow away for minimal bulk during launch. Advances in all aspects of radiator design, construction, and analysis will be necessary to enable such future missions. Currently, the best means for obtaining high strength along with flexibility is through structures known as fabrics. The development of new materials and bonding techniques has extended the application range of fabrics into areas traditionally dominated by monolithic and/or metallic structures. Given that even current spacecraft heat rejection considerations tend to dominate spacecraft design and mass, the larger and more complex designs of the future face daunting challenges in thermal control. Ceramic fabrics bonded to ultra-thin metal liners (foils) have the potential of achieving radiator performance levels heretofore unattainable, and of readily matching the advances made in other branches of spacecraft design. The research effort documented here indicates that both pumped loops and heat pipes constructed in ceramic fabrics stand to benefit in multiple ways. Flexibility and low mass are the main advantages exhibited by fabric radiators over conventional metal ones. We feel that fabric radiators have intrinsic merits not possessed by any other radiator design and need to be researched further. 26 refs., 16 figs., 17 tabs.

Antoniak, Z.I.; Krotiuk, W.J.; Webb, B.J.; Prater, J.T.; Bates, J.M.

1988-01-01

278

DNA fragmentation pattern in human fibroblasts after irradiation with iron ions  

NASA Astrophysics Data System (ADS)

In this work we studied the fragmentation pattern produced by the double stand breaks (DSB) induced in AG1522 primary human fibroblasts by two different iron beams, one of energy 414 MeV/u, and the other of energy 115 MeV/u (with dose-average LET in water equal to 202 keV/m and 442 keV/m, respectively). Irradiation with several doses up to 200 Gy was performed at the HIMAC facility of the National Institute of Radiological Sciences, Chiba, Japan. Experimental data, first obtained for fragments belonging to the size ranges 23-1000 kbp and 1000-5700 kbp (Belli et al., 2006), have successively been obtained also for fragments belonging to the size ranges 1-9 kbp and 9-23 kbp; the experimental analysis was performed with pulsed and constant field electrophoresis. The RBE for DSB production was evaluated in two different fragment size ranges (i.e., 23-5700 kbp and 1-5700 kbp), and it was found larger for the wider size range, especially for the beam with the higher LET. The experimental results have been compared to those computed on the basis of the Monte Carlo PARTRAC simulation code, following the line of research started in Campa et al. (2005), and exploiting the recent update of the PARTRAC code to ions heavier than helium (Friedland et al., 2006). Because the agreement has been found satisfactory for both radiation qualities, the spectra outside the experimentally observable fragment size range were also computed in order to evaluate the overall fragmentation pattern. The marked increases of the RBEs for DSB production, obtained when also the very small fragments (< 1 kbp) are included, makes them closer to the RBE values observed for the late cellular effects. This finding is a further indication for the biological significance of the spatial correlation of DSB at short distances. This work was partially supported by ASI (Italian Space Agency, "Mo-Ma/COUNT" project). References M. Belli, A. Campa, V. Dini, G. Esposito, Y. Furusawa, G. Simone, E. Sorrentino and M. A. Tabocchini. DNA fragmentation induced in human fibroblasts by accelerated 56 Fe ions of differing energies. Radiat. Res. 165, 713-720 (2006). A. Campa, F. Ballarini, M. Belli, R. Cherubini, V. Dini, G. Esposito, W. Friedland, S. Gerardi, S. Molinelli, A. Ottolenghi, H. G. Paretzke, G. Simone and M. A. Tabocchini. DNA DSB induced in human cells by charged particles and gamma rays: experimental results and theoretical approaches. Int. J. Radiat. Biol. 81, 841-854 (2005). W. Friedland, P. Jacob, H. G. Paretzke, A. Ottolenghi, F. Ballarini and M. Liotta. Simulation of light ion induced DNA damge patterns. Radiat. Prot. Dosim. 122, 116-120 (2006).

Campa, Alessandro

279

Bile Duct (Cholangiocarcinoma) Cancer: Radiation Therapy  

MedlinePLUS

... cancer Next Topic Chemotherapy for bile duct cancer Radiation therapy for bile duct cancer Radiation therapy is ... are different kinds of radiation therapy. External beam radiation therapy (EBRT) This type of radiation therapy uses ...

280

Unintentional radiation from shielded transformers  

Microsoft Academic Search

It is shown experimentally that a typical shielded broadband transformer intended for bulk current injection measurements radiates far-field electromagnetic energy. This radiation occurs in spite of the shield and is distinct from any radiation due to common mode currents on the exterior of the coaxial feed transmission line. The radiation patterns presented here taken together with previous results which showed

James McLean; Robert Sutton

2010-01-01

281

Radiation Therapy for Skin Cancer  

MedlinePLUS

... melanoma.org Skin Cancer Foundation www.skincancer.org Radiation Therapy Answers www.rtanswers.org AMERICAN SOCIETY FOR RADIATION ... visit: National Cancer Institute www.cancer.gov/clinicaltrials Radiation Therapy Answers www.rtanswers.org Radiation Therapy Oncology Group ...

282

Health effects of ionizing radiation  

SciTech Connect

Although humans have evolved in an environment of ionizing radiation, it was not until man-made sources were developed that the effects of ionizing radiation started to become known. Detection and measurement of radiation is not only sophisticated but widely applied. This article deals with exposure to this kind of radiation and the risk it may cause.

Fry, R.J.; Fry, S.A. (Oak Ridge National Laboratory, TN (USA))

1990-03-01

283

Interaction of Radiation with Matter  

SciTech Connect

A flash introductory course in the interaction of ionizing radiation with matter is presented for students starting out in nuclear physics, medical applications of radiation, materials modification, radiation damage, detectors, materials analysis, radiation protection, and other applications. Emphasis is on defining basic concepts and on a simple visualization of ideas for practical applications, rather than on completeness or rigor.

Rickards, J. [Instituto de Fisica, Universidad Nacional Autonoma de Mexico, Apartado Postal 20-364, Mexico, D.F., 01000 (Mexico)

2010-09-10

284

Radiation Sensitization in Cancer Therapy.  

ERIC Educational Resources Information Center

|Discusses various aspects of radiation damage to biological material, including free radical mechanisms, radiation sensitization and protection, tumor hypoxia, mechanism of hypoxic cell radiosensitization, redox model for radiation modification, sensitizer probes of cellular radiation targets, pulse radiolysis studies of free radical kinetics,

Greenstock, Clive L.

1981-01-01

285

The Radiation Chemistry Data Center  

NSDL National Science Digital Library

The Radiation Chemistry Data Center is an information resource provided by the Notre Dame Radiation Laboratory that is "dedicated to the collection, evaluation, and dissemination of data characterizing the reactions of transient intermediates produced by radiation chemical and photochemical methods." The main page offers links to Compilations of Chemical Property Data, Kinetics Databases, a Bibliographic Database, and Recent Papers in Radiation Chemistry and Photochemistry.

2002-01-01

286

The Radiation Chemistry Data Center  

NSDL National Science Digital Library

The Radiation Chemistry Data Center is an information resource provided by the Notre Dame Radiation Laboratory that is "dedicated to the collection, evaluation, and dissemination of data characterizing the reactions of transient intermediates produced by radiation chemical and photochemical methods." The main page offers links to Compilations of Chemical Property Data, Kinetics Databases, a Bibliographic Database, and Recent Papers in Radiation Chemistry and Photochemistry.

Madden, K. P.

2007-05-15

287

Radiation by relativistic dipoles. III  

Microsoft Academic Search

The classical radiation of a point magnetic moment (a magneton) moving at a constant velocity in an arbitrary direction with respect to the field lines of a uniform magnetic field is analyzed. All characteristics of the radiation agree with the Ternov-Bagrov-Khapaev relativistic quantum thoery of the radiation by a neutron. It is thus demonstrated that the classical model of radiation

V. A. Bordovitsyn; V. S. Gushchina

1994-01-01

288

Radiation nephritis causing nephrotic syndrome  

SciTech Connect

Clinical symptoms of acute radiation nephritis with nephrotic syndrome developed in a fifty-six-year-old woman after abdominal radiation therapy for an astrocytoma of the spinal cord. The diagnosis of radiation nephritis was confirmed by renal biopsy. To our knowledge, this is the first documented case of radiation nephritis associated with nephrotic syndrome.

Jennette, J.C.; Ordonez, N.G.

1983-12-01

289

Radiation in Particle Simulations  

SciTech Connect

Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of megabars to thousands of gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present four methods that attempt a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The first method applies the Lienard-Weichert solution of Maxwell's equations for a classical particle whose motion is assumed to be known. The second method expands the electromagnetic field in normal modes (planewaves in a box with periodic boundary-conditions) and solves the equation for wave amplitudes coupled to the particle motion. The third method is a hybrid molecular dynamics/Monte Carlo (MD/MC) method which calculates radiation emitted or absorbed by electron-ion pairs during close collisions. The fourth method is a generalization of the third method to include small clusters of particles emitting radiation during close encounters: one electron simultaneously hitting two ions, two electrons simultaneously hitting one ion, etc. This approach is inspired by the virial expansion method of equilibrium statistical mechanics. Using a combination of these methods we believe it is possible to do atomic-scale particle simulations of fusion ignition plasmas including the important effects of radiation emission and absorption.

More, R; Graziani, F; Glosli, J; Surh, M

2010-11-19

290

Radiation Protection in Canada  

PubMed Central

The current status of radiation protection in Canada is discussed in the last of a three-part series. Particular emphasis has been placed on the role of the Radiation Protection Division of the Department of National Health and Welfare. A radioactive fallout study program has been established involving the systematic collection of air and precipitation samples from 24 locations, soil samples from 23 locations, fresh-milk samples from 16 locations, wheat samples from nine areas and human-bone specimens from various hospitals throughout Canada. A whole-body-counting facility and a special study of fallout in Northern areas have also been initiated. For any age group, the highest average strontium-90 concentration in human bone so far reported has been less than four picocuries per gram of calcium compared with the maximum permissible level of 67 derived from the International Committee on Radiation Protection (ICRP) recommendations. By the end of 1963 a general downward trend of levels of radioactivity detected in other parts of the program has been observed. Programs to assess the contribution to the radiation exposure of members of the population from medical x-rays, nuclear reactor operations and natural background-radiation sources have also been described. The annual genetically significant dose from diagnostic x-ray examinations in Canadian public hospitals has been estimated to be 25.8 mrem. Results from the reactor-environment monitoring programs have not suggested the presence of radioactivity beyond that contributed from fallout.

Bird, P. M.

1964-01-01

291

Reducing Radiation Damage  

ScienceCinema

This talk describes the use of a modified treatment sequence, i.e., radiation dose, geometry, dwell time, etc., to mitigate some of the deleterious effects of cancer radiotherapy by utilizing natural cell repair processes. If bad side effects can be reduced, a more aggressive therapy can be put into place. Cells contain many mechanisms that repair damage of various types. If the damage can not be repaired, cells will undergo apoptosis (cell death). Data will be reviewed that support the fact that a small dose of radiation will activate damage repair genes within a cell. Once the mechanisms are fully active, they will efficiently repair the severe damage from a much larger radiation dose. The data ranges from experiments on specific cell cultures using microarray (gene chip) techniques to experiments on complete organisms. The suggested effect and treatment is consistent with the assumption that all radiation is harmful, no matter how small the dose. Nevertheless, the harm can be reduced. These mechanisms need to be further studied and characterized. In particular, their time dependence needs to be understood before the proposed treatment can be optimized. Under certain situations it is also possible that the deleterious effects of chemotherapy can be mitigated and the damage to radiation workers can be reduced.

292

Reducing Radiation Damage  

SciTech Connect

This talk describes the use of a modified treatment sequence, i.e., radiation dose, geometry, dwell time, etc., to mitigate some of the deleterious effects of cancer radiotherapy by utilizing natural cell repair processes. If bad side effects can be reduced, a more aggressive therapy can be put into place. Cells contain many mechanisms that repair damage of various types. If the damage can not be repaired, cells will undergo apoptosis (cell death). Data will be reviewed that support the fact that a small dose of radiation will activate damage repair genes within a cell. Once the mechanisms are fully active, they will efficiently repair the severe damage from a much larger radiation dose. The data ranges from experiments on specific cell cultures using microarray (gene chip) techniques to experiments on complete organisms. The suggested effect and treatment is consistent with the assumption that all radiation is harmful, no matter how small the dose. Nevertheless, the harm can be reduced. These mechanisms need to be further studied and characterized. In particular, their time dependence needs to be understood before the proposed treatment can be optimized. Under certain situations it is also possible that the deleterious effects of chemotherapy can be mitigated and the damage to radiation workers can be reduced.

Blankenbecler, Richard

2006-06-05

293

AREA RADIATION MONITOR  

DOEpatents

S>An improved area radiation dose monitor is designed which is adapted to compensate continuously for background radiation below a threshold dose rate and to give warning when the dose integral of the dose rate of an above-threshold radiation excursion exceeds a selected value. This is accomplished by providing means for continuously charging an ionization chamber. The chamber provides a first current proportional to the incident radiation dose rate. Means are provided for generating a second current including means for nulling out the first current with the second current at all values of the first current corresponding to dose rates below a selected threshold dose rate value. The second current has a maximum value corresponding to that of the first current at the threshold dose rate. The excess of the first current over the second current, which occurs above the threshold, is integrated and an alarm is given at a selected integrated value of the excess corresponding to a selected radiation dose. (AEC)

Manning, F.W.; Groothuis, S.E.; Lykins, J.H.; Papke, D.M.

1962-06-12

294

Stereotactic body radiation therapy.  

PubMed

Stereotactic body radiation therapy constitutes an emerging therapeutic paradigm. These treatments are unique relative to the large body of experience with conventional fractionated radiotherapy. On the basis of the treatment principles of intracranial stereotactic radiation combined with enhancements associated with immobilization and imaging, the role of extracranial treatment continues to evolve. However, most clinical reports on extracranial treatments suffer from short or incomplete follow-up, making final assessments of benefit and toxicity, particularly late toxicity, problematic. These techniques are centered on a very basic understanding of the use of ionizing radiation for the treatment of cancer. Nonetheless, they do require a unique and special understanding of radiobiologic and physics principles. It is hoped that using high-dose, single-fraction treatment or a few fractions of treatment, the therapeutic ratio is improved, thus potentially changing the way some cancers are treated. Ideally, all patients receiving such treatments would be enrolled in formal protocols. As data accrue and understanding of these techniques improve, it will be possible to better define the indications for stereotactic body radiation therapy. At that time, appropriate applications can be submitted for permanent billing codes that will describe a process of care that embraces this technology without vendor favoritism. This review summarizes the state of stereotactic body radiation in 2005. PMID:17411904

Potters, Louis; Timmerman, Robert; Larson, David

2005-08-01

295

Uses of synchrotron radiation  

SciTech Connect

X-ray fluorescence has long been used as a technique for elemental analysis. X-ray fluorescence techniques have a number of features that make them attractive for application to biomedical samples. In the past few years synchrotron radiation x-ray sources have been developed and, because of their properties, their use can improve the sensitivity for trace element analysis by two to three orders of magnitude. Also, synchrotron radiation will make possible an x-ray microprobe with resolution in the micrometer range. The National Synchrotron Light Source (NSLS), a dedicated synchrotron radiation source recently built at Brookhaven National Laboratory, will have a facility for trace element analysis by x-ray fluorescence and will be available to all interested users.

Gordon, B.M.

1982-01-01

296

Semiconductor radiation detector  

SciTech Connect

A semiconductor detector for ionizing electromagnetic radiation, neutrons, and energetic charged particles. The detecting element is comprised of a compound having the composition I-III-VI.sub.2 or II-IV-V.sub.2 where the "I" component is from column 1A or 1B of the periodic table, the "II" component is from column 2B, the "III" component is from column 3A, the "IV" component is from column 4A, the "V" component is from column 5A, and the "VI" component is from column 6A. The detecting element detects ionizing radiation by generating a signal proportional to the energy deposited in the element, and detects neutrons by virtue of the ionizing radiation emitted by one or more of the constituent materials subsequent to capture. The detector may contain more than one neutron-sensitive component.

Bell, Zane W. (Oak Ridge, TN); Burger, Arnold (Knoxville, TN)

2010-03-30

297

Space radiation protection issues.  

PubMed

The complex charged particle environments in space pose considerable challenges with regard to potential health consequences that can impact mission design and crew selection. The lack of knowledge of the biological effects of different ions in isolation and in combination is a particular concern because the risk uncertainties are very high for both cancer and non-cancer late effects. Reducing the uncertainties is of high priority. Two principal components of space radiation each raise different concerns. Solar particle events (SPE) occur sporadically and are comprised primarily of low- to moderate-energy protons. Galactic cosmic radiation (GCR) is isotropic and relatively invariant in dose rate. GCR is also dominated by protons, but the energy range is wider than in SPE. In addition, the contribution of other light and heavy ions to the health risks from GCR must be addressed. This paper will introduce the principal issues under consideration for space radiation protection. PMID:23032885

Kronenberg, Amy; Cucinotta, Francis A

2012-11-01

298

Properties of undulator radiation  

SciTech Connect

Properties of the radiation emitted by a plane sinusoidal undulator are calculated in the far field approximation. Software has been developed to calculate the spectral distribution and polarization of the radiated intensity I(E) at a point on (or integrated over) a cross sectional observation plane of the photon beam. Spatial distribution of monochromatic radiation and power density contours are also calculated. Spectral broadening caused by an electron beam of finite spatial distribution is considered. Dispersive properties of the photon beam, including the dependence on deflection parameter, are analyzed. It is shown that reasonably constant intensity distribution I(E) can be obtained by properly shaping the beam acceptance aperture. 5 refs., 11 figs.

Veal, B.W.

1985-11-01

299

Composition for radiation shielding  

DOEpatents

A composition for use as a radiation shield is disclosed. The shield has a depleted uranium core for absorbing gamma rays and a bismuth coating for preventing chemical corrosion and absorbing gamma rays. Alternatively, a sheet of gadolinium may be positioned between the uranium core and the bismuth coating for absorbing neutrons. The composition is preferably in the form of a container for storing materials that emit radiation such as gamma rays and neutrons. The container is preferably formed by casting bismuth around a pre-formed uranium container having a gadolinium sheeting, and allowing the bismuth to cool. The resulting container is a structurally sound, corrosion-resistant, radiation-absorbing container. 2 figs.

Kronberg, J.W.

1994-08-02

300

Audible radiation monitor  

DOEpatents

A method and apparatus for monitoring ionizing radiation comprising radiation detectors in electrical connection with an isotopic analyzer and a device for producing chords to which each isotope is mapped so that the device produces a unique chord for each isotope. Preferably the chords are pleasing to the ear, except for chords representing unexpected isotopes, and are louder or softer depending on the level of radioactivity produced by each isotope, and musical instrument voices may be simulated in producing the chords as an aid to distinguishing similar-sounding chords. Because of the representation by chords, information regarding the level and composition of the radiation in an area can be conveyed to workers in that area more effectively and yet without distracting them.

Odell, Daniel M. C. (11 Russellwood Ct., Aiken, SC 29803)

1993-01-01

301

Continuum radiation at Uranus  

NASA Astrophysics Data System (ADS)

One Uranian radio emission which has thus far escaped attention is an analog of continuum radiation at earth, Jupiter, and Saturn. The emission is found to be propagating in the ordinary mode in the range of one to a few kHz on the inbound leg of the Voyager 2 encounter, shortly after the magnetopause crossing. The Uranian continuum radiation is notably weak, making it more like that detected at Saturn than the extremely intense Jovian continuum radiation. The Uranian emission shows some evidence for narrow-band components lying in the same frequency regime as the continuum, completing the analogy with the other planets, which also show narrow-band components superimposed on the continuum spectrum. It is argued that the low intensity of the Uranian continuum is most likely related to the lack of a density cavity within the Uranian magnetosphere that is deep relative to the solar wind plasma density.

Kurth, W. S.; Gurnett, D. A.; Desch, M. D.

1990-02-01

302

Extragalactic Background Radiation  

NASA Astrophysics Data System (ADS)

Contents; Preface; List of participants; 1. Introduction P. J. E. Peebles; 2. Extragalactic gamma-ray background N. Gehrels and C. Cheung; 3. The X-ray background (observations) G. Zamorani; 4. Extragalactic ultraviolet background radiation R. C. Henry and J. Murthy; 5. Ultraviolet background (theory) P. Jakobsen; 6. The optical extragalactic background radiation J. A. Tyson; 7. Infrared background (observations) M. G. Hauser; 8. The infrared background (theory) C. J. Lonsdale; 9. Microwave background radiation (observations) J. C. Mather; 10. Detection of degree scale anisotropy P. M. Lubin; 11. Cosmic microwave background anisotropies and structure formation in the universe N. Vittorio; The radio background emission - the long and short of it M. S. Longair; 13. The radio background: radio-loud galaxies at high and low redshifts J. A. Peacock; 14. Conference summary M. J. Rees.

Calzetti, Daniela; Livio, Mario; Madau, Piero

1995-01-01

303

SODA: Solar Radiation Database  

NSDL National Science Digital Library

The Solar Database, or SoDa, is described as an integration and exploitation of networked Solar radiation Databases for environment monitoring and as a project that aims to integrate European-wide solar radiation resources (i.e. databases, processing chains and educational resources) into one, thematically organized, Web site. The search tool allows users to search for data from a variety of sources including Long Term Time Series Data, Climatological Data, Simulation of Radiation Under Clear Skies Data, Solar Energy Systems Data, and much more. Once a particular set is located, the user can view a description of the source and contents of the data, as well as click on the provided links to access them.

304

String radiative backreaction  

SciTech Connect

We discuss radiative backreaction for global strings described by the Kalb-Ramond action with an analogous derivation to that for the point electron in classical electrodynamics. We show how local corrections to the equations of motion allow one to separate the self-field of the string from that of the radiation field. Modifications to this {open_quote}{open_quote}local backreaction approximation{close_quote}{close_quote} circumvent the runaway solutions, allowing these corrections to be used to evolve string trajectories numerically. Comparisons are made with analytic and numerical radiation calculations from previous work and the merits and limitations of this approach are discussed. {copyright} {ital 1995 The American Physical Society.}

Battye, R.A.; Shellard, E.P. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge, CB3 9EW (United Kingdom)]|[Isaac Newton Institute for Mathematical Sciences, Clarkson Road, Cambridge CB3 0EH (United Kingdom)

1995-12-01

305

Radiation oncology (Vol. 2)  

SciTech Connect

This volume of the Radiation Oncology series features update reports on the current status of primary therapy for lung cancer and the role of radiation therapy in the treatment of hepatomas. Other articles describe the use of stereotaxic interstitial implantation in the treatment of malignant brain tumors and discuss the indications for and results of radiation as the primary or adjuvant treatment of large bowel cancer. Reports on new technological developments examine the biological basis and clinical potential of local-regional hyperthermia and photodynamic therapy. Included are reviews of the role of magnetic resonance imaging in the diagnostic evaluation of cancer and of three-dimensional treatment planning for high energy external beam radiotherapy.

Phillips, T.L.; Wara, W.

1987-01-01

306

Radiation techniques for acromegaly  

PubMed Central

Radiotherapy (RT) remains an effective treatment in patients with acromegaly refractory to medical and/or surgical interventions, with durable tumor control and biochemical remission; however, there are still concerns about delayed biochemical effect and potential late toxicity of radiation treatment, especially high rates of hypopituitarism. Stereotactic radiotherapy has been developed as a more accurate technique of irradiation with more precise tumour localization and consequently a reduction in the volume of normal tissue, particularly the brain, irradiated to high radiation doses. Radiation can be delivered in a single fraction by stereotactic radiosurgery (SRS) or as fractionated stereotactic radiotherapy (FSRT) in which smaller doses are delivered over 5-6 weeks in 25-30 treatments. A review of the recent literature suggests that pituitary irradiation is an effective treatment for acromegaly. Stereotactic techniques for GH-secreting pituitary tumors are discussed with the aim to define the efficacy and potential adverse effects of each of these techniques.

2011-01-01

307

New radiative shocks experiment  

NASA Astrophysics Data System (ADS)

An experimental study of shocks with astrophysical relevance is performed with the high energy density laser of the LULI, at the Ecole Polytechnique. The peculiarity of these shocks is the strong coupling between radiation and hydrodynamics which leads to a structure governed by a radiative precursor. A new experiment has been performed this year where we have observed shocks identified as radiative shocks. We study them in various experimental configurations (several speeds and geometries of the medium where the shock propagates, allowing a quasi-planar or a quasi-spherical expansion). From the measurements it is possible to infer several features of the shock such as the speed, the electronic density, the geometrical shape and spectroscopic informations. The results will be studied with numerical simulations.

Leygnac, S.; Bouquet, S.; Stehl, C.; Benuzzi, A.; Boireau, J.-P.; Chize, J.-P.; Grandjouan, N.; Huser, G.; Koenig, M.; Malka, V.; Merdji, H.; Michaut, C.; Thais, F.; Vinci, T.

2002-06-01

308

Personal radiation dosimeter  

SciTech Connect

A radiation dosimeter is described comprising: at least a first capacitive ionization chamber adapted to gradually discharge in the presence of incident radiation; a voltage source; a load resistor coupled to the voltage source; a first switch means coupled to the load resistor and the voltage source to form a first in-series circuit comprising the voltage source, the load resistor and the first switch means; a second switch means coupled to the load resistor and the voltage source to form a second in-series circuit comprising the voltage source, the load resistor, the second switch means and at least first capacitive ionization chamber; peak voltage sensing means coupled across the load resistor for providing a peak voltage signal; and calculating means responsive to peak voltage measurements taken across the load resistor as the first and second switch means are sequentially actuated for calculating the amount of radiation incident on the dosimeter from the peak voltage measurements.

Terhune, J.H.

1986-08-12

309

Solar radiation modelling  

NASA Astrophysics Data System (ADS)

The Sun is the main energy source of the life on the Earth. Thus, solar radiation energy data and models are important for many areas of research and applications. Many parameters influence the amount of solar energy at a particular standing point of the Earth's surface; therefore, many solar radiation models were produced in the last few years. Solar radiation energy depends mostly on incidence angle, which is defined by astronomical and surface parameters. Our solar radiation model is based on defining incidence angle by computing normal-to-the-surface tangent plane and direction of the Sun. If a part of the surface is in the shadow, it receives lesser energy than sunny areas. That is why shadow determination is an important part of the model. The sky is usually not completely clear, so meteorological parameters had to be integrated into the model. Meteorological model distinguishes among direct and diffuse Sun radiation. The model was tested and implemented for the whole Slovenia and it was also compared with previous studies. Case study surface data were calculated from the DEM with a 25 m resolution. The astronomical data, which were required for virtual Sun motion simulation around the Earth, were derived from the astronomical almanac. Meteorological data were acquired from observed mean values on 24 meteorological stations between 1961 and 1990. All calculations were made for hours and decades and finally, the annual quasiglobal radiation energy, which is the energy received by inclined plane from the Sun in one year, was calculated from the sum of all the energies of all the decades.

Zakek, Klemen; Podobnikar, Toma; Otir, Kritof

2005-03-01

310

Radiation in Particle Simulations  

SciTech Connect

Hot dense radiative (HDR) plasmas common to Inertial Confinement Fusion (ICF) and stellar interiors have high temperature (a few hundred eV to tens of keV), high density (tens to hundreds of g/cc) and high pressure (hundreds of Megabars to thousands of Gigabars). Typically, such plasmas undergo collisional, radiative, atomic and possibly thermonuclear processes. In order to describe HDR plasmas, computational physicists in ICF and astrophysics use atomic-scale microphysical models implemented in various simulation codes. Experimental validation of the models used to describe HDR plasmas are difficult to perform. Direct Numerical Simulation (DNS) of the many-body interactions of plasmas is a promising approach to model validation but, previous work either relies on the collisionless approximation or ignores radiation. We present four methods that attempt a new numerical simulation technique to address a currently unsolved problem: the extension of molecular dynamics to collisional plasmas including emission and absorption of radiation. The first method applies the Lienard-Weichert solution of Maxwell's equations for a classical particle whose motion is assumed to be known (section 3). The second method expands the electromagnetic field in normal modes (plane-waves in a box with periodic boundary-conditions) and solves the equation for wave amplitudes coupled to the particle motion (section 4). The third method is a hybrid MD/MC (molecular dynamics/Monte Carlo) method which calculates radiation emitted or absorbed by electron-ion pairs during close collisions (section 5). The fourth method is a generalization of the third method to include small clusters of particles emitting radiation during close encounters: one electron simultaneously hitting two ions, two electrons simultaneously hitting one ion, etc.(section 6). This approach is inspired by the Virial expansion method of equilibrium statistical mechanics.

More, R M; Graziani, F R; Glosli, J; Surh, M

2009-06-15

311

Radiation monitor for liquids  

DOEpatents

A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans.

Koster, James E. (Los Alamos, NM); Bolton, Richard D. (Los Alamos, NM)

1999-01-01

312

Radiation monitor for liquids  

DOEpatents

A radiation monitor for use with liquids that utilizes air ions created by alpha radiation emitted by the liquids as its detectable element. A signal plane, held at an electrical potential with respect to ground, collects these air ions. A guard plane or guard rings is used to limit leakage currents. In one embodiment, the monitor is used for monitoring liquids retained in a tank. Other embodiments monitor liquids flowing through a tank, and bodies of liquids, such as ponds, lakes, rivers and oceans. 4 figs.

Koster, J.E.; Bolton, R.D.

1999-03-02

313

The radiative Reynolds number  

NASA Astrophysics Data System (ADS)

The radiative Reynolds number (RRN) is defined as a parameter characterizing the stability of low-temperature current-carrying plasma in high-current radiating discharges (such as are used for the pumping of high-power lasers). The RRN approach is used to examine the stability of plasmas and other objects in fields of intrinsic thermal emission; processes in MHD converters, gas lasers, and the cosmic plasma are examined. It is shown that in all cases where the RRN is sufficiently large the overheating instability (such as occurs in the solar photosphere) arises and the plasma becomes turbulent.

Rozanov, V. B.; Rukhadze, A. A.

314

Diffraction radiation generators  

NASA Astrophysics Data System (ADS)

Research in the field of diffraction radiation generators (DRG) conducted at the Radio Physics and electronics Institute of the Ukranian Academy of Sciences over the past 25 years is reviewed. The effect of diffraction radiation is analyzed in detail, and various operating regimes of DRGs are discussed. The discussion then focuses on the principal requirements for the design of packaged DRGs and their principal parameters. Finally, applications of DRGs in various fields of science and technology are reviewed, including such applications as DRG spectroscopy, diagnostics of plasma, biological specimens, and vibration, and DRG radar systems.

Shestopalov, Viktor P.; Vertii, Aleksei A.; Ermak, Gennadii P.; Skrynnik, Boris K.; Khlopov, Grigorii I.; Tsvyk, Aleksei I.

315

Radiation Detectors and Art  

NASA Astrophysics Data System (ADS)

The use of radiation detectors in the analysis of art objects represents a very special application in a true interdisciplinary field. Radiation detectors employed in this field detect, e.g., x-rays, ?-rays, ? particles, and protons. Analyzed materials range from stones, metals, over porcelain to paintings. The available nondestructive and noninvasive analytical methods cover a broad range of techniques. Hence, for the sake of brevity, this chapter will concentrate on few techniques: Proton Induced X-ray Emission (PIXE) and Proton Induced ?-ray Emission (PIGE).

Denker, Andrea

316

Weak radiative hyperon decays  

NASA Astrophysics Data System (ADS)

The problem of weak radiative hyperon decays (WRHD) is reviewed. With the rcent measurement of the ?0 -> ?? asymmetry confirming Hara's theorem, implications from its violation in low-energy theoretical approaches are discussed. It is shown how an underlying symmetry link should be formulated for a successful description of both nonleptonic and radiative weak hyperon decays. The sign of the ?0 -> ?? asymmetry and the overall size of parity-violating WRHD amplitudes together lead to the resolution of the old S:P problem in nonleptonic decays.

?enczykowski, P.

2003-02-01

317

Control of radiation injury  

US Patent & Trademark Office Database

Methods of treating radiation injury of a subject in need thereof comprising administering to the subject a peptide consisting of an amino acid molecule selected from the group consisting of VVC, LAG, AQG, LQGV, QVVC, MTRV, LAGV, LQAV, PGCP, VGQL, RVLQ, EMFQ, AVAL, FVLS, NMWD, LCFL, FSYA, FWVD, AFTV, LGTL, QLLG, YAIT, APSL, ITTL, QALG, GVLC, NLIN, SPIE, LNTI, LHNL, CPVQ, EVVR, MTEV, EALE, EPPE, LGTL, VGGI, RLPG, LQGA, LCFL, TLAVE, VEGNL, LNEAL, CPRGVNP, MGGTWA, LTCDDP, VCNYRDV, QPLAPLVG, and DINGFLPAL. The invention provides for administration of the peptide prior to and following exposure of the subject to a source of radiation.

Benner; Robbert (Barendrecht, NL); Khan; Nisar Ahmed (Rotterdam, NL); Carlton; Richard Michael (Washington, NY)

2012-10-16

318

Modification of radiation response  

SciTech Connect

There has been a substantial and intense interest by laboratory and clinical investigators in the development of agents which modify the response of tissue to radiation differentially so as to increase the effect on tumor relative to normal tissue. These have included efforts to increase the response of tumor or to decrease response of normal tissue. The plan of this presentation is to: define radiation response modifiers; consider the impact of response modifiers on dose response curves; comment on problems inherent in assessment of results of clinical trials of response modifiers; and review briefly results of several trials of: sensitizers of hypoxic cells (hyperbaric oxygen, chemical sensitizer), pyrimidine analogs, and protectors.

Suit, H.D.

1984-01-01

319

RADIATION MEASURING DEVICES  

DOEpatents

A radiation-measuring device is described having an a-c output. The apparatus has a high-energy particle source responsive to radiation flux disposed within a housing having a pair of collector plates. A potential gradient between the source and collector plates causes ions to flow to the plates. By means of electrostatic or magnetic deflection elements connected to an alternating potential, the ions are caused to flow alternately to each of the collector plates causing an a-c signal thereon.

Bouricius, G.M.B.; Rusch, G.K.

1960-03-22

320

Radiation Imaging and Attenuation  

NASA Astrophysics Data System (ADS)

X-ray and neutron images are used to demonstrate materials' different radiation attenuation properties. This leads to discussion of applications in medicine, industry and research. The Penn State Radiation Science and Engineering Center (RSEC) uses neutron radioscopy to image the inside of a working hydrogen fuel cell. This is one of the many educational activities that are conducted when students visit the RSEC. To encourage pre-college students to apply these principles and learn more about nuclear technology, we are sponsoring a design competition. For more information visit www.rsec.psu.edu

Davison, Candace; Yocum, Douglas

2008-03-01

321

THz radiation sensors  

NASA Astrophysics Data System (ADS)

In the paper, issues associated with the development and exploitation of terahertz (THz) radiation detectors are discussed. The paper is written for those readers who desire an analysis of the latest developments in different type of THz radiation sensors (detectors), which play an increasing role in different areas of human activity (e.g., security, biological, drugs and explosions detection, imaging, astronomy applications, etc.). The basic physical phenomena and the recent progress in both direct and heterodyne detectors are discussed. More details concern Schottky barrier diodes, pair braking detectors, hot electron mixers, and field-effect transistor detectors. Also the operational conditions of THz detectors and their upper performance limits are discussed.

Sizov, F.

2010-03-01

322

Problems in astrophysical radiation hydrodynamics  

SciTech Connect

The basic equations of radiation hydrodynamics are discussed in the regime that the radiation is dynamically as well as thermally important. Particular attention is paid to the question of what constitutes an acceptable approximate non-relativistic system of dynamical equations for matter and radiation in this regime. Further discussion is devoted to two classes of application of these ideas. The first class consists of problems dominated by line radiation, which is sensitive to the velocity field through the Doppler effect. The second class is of problems in which the advection of radiation by moving matter dominates radiation diffusion.

Castor, J.I.

1983-09-14

323

Radiation Hard Fiber Optics.  

National Technical Information Service (NTIS)

A study of radiation-inducted absorption in low-loss optical waveguides is reported. Step-index optical fibers were prepared from preforms fabricated by the CVD method. The germanium silicate core glass in the fibers was doped with varying amounts of anti...

R. E. Jaeger M. Aslami

1981-01-01

324

Radiation Source Replacement Workshop  

SciTech Connect

This report summarizes a Radiation Source Replacement Workshop in Houston Texas on October 27-28, 2010, which provided a forum for industry and researchers to exchange information and to discuss the issues relating to replacement of AmBe, and potentially other isotope sources used in well logging.

Griffin, Jeffrey W.; Moran, Traci L.; Bond, Leonard J.

2010-12-01

325

The radiation design handbook  

NASA Astrophysics Data System (ADS)

A handbook which provides general engineering guidelines suitable for project groups engaged in the design of spacecraft required to operate in regions of space where they will be exposed to significant doses of radiation is presented. The charged particle environment in geomagnetospheric space, and the physics of radiation effects on solid state devices and materials (including ionization effects, single event upsets and bulk displacement damage) in all the designs of devices likely to be used in spacecraft are discussed. Methods of assessing the impact of these effects are given, including procedures for calculating the orbital radiation environment, dose depth curves within electronic enclosures, and the end of life degradation of devices and circuits. While no rigid procedures for handling these problems can be set out, special attention is given to methods of alleviating the problems presented. These methods cover tradeoff studies of orbit versus shield weight, layout rules for spacecraft, the use of redundancy and housekeeping dosimetry, device selection, device verification, and the design of radiation tolerant circuits.

1993-05-01

326

Continuum radiation at Uranus  

SciTech Connect

Uranus has proven to be a radio source of remarkable complexity with as many as six distinctly different types of emission. One Uranian radio emission which has thus far escaped attention is an analog of continuum radiation at Earth, Jupiter, and Saturn. The emission is found to be propagating in the ordinary mode in the range of one to a few kHz on the inbound leg of the Voyager 2 encounter, shortly after the magnetopause crossing. The continuum radiation spectrum at Uranus also includes bands with frequencies as high as 12 kHz or greater on both the inbound and outbound legs. The Uranian continuum radiation is notably weak, making it more like that detected at Saturn than the extremely intense Jovian continuum radiation. The Uranian emission shows some evidence for narrow-band components lying in the same frequency regime as the continuum, completing the analogy with the other planets, which also show narrow-band components superimposed on the continuum spectrum. The authors argue that the low intensity of the Uranian continuum is most likely related to the lack of a density cavity within the Uranian magnetosphere that is deep relative to the solar wind plasma density.

Kurth, W.S.; Gurnett, D.A. (Univ. of Iowa, Iowa City (United States)); Desch, M.D. (NASA Goddard Space Flight Center, Greenbelt, MD (United States))

1990-02-01

327

Radiative Capacity of Pyrographite.  

National Technical Information Service (NTIS)

Pyrographite possesses a highly-oriented structure which conditions the anisotropy of its properties. An investigation was made of the radiative capacity of pyrographite at a wavelength of 0.55 microns which was obtained by the vacuum method at various de...

A. N. Romanov B. M. Barykin E. G. Spiridonov

1972-01-01

328

Dosimetry of pulsed radiation  

SciTech Connect

International Commission on Radiation Units and Measurements (ICRU) Report 34 provides guidance on the special procedures to be followed in measuring the radiation dose from sources such as linear accelerators, betatrons, synchrotrons, or field-emission impulse generators. These sources deliver their output impulses within the range 10/sup -9/ to 10/sup -6/ seconds, spaced at least a few milliseconds apart. Condenser discharge machines with field-emission cathodes deliver much larger pulses, usually singly or at very low frequency, and with a pulse duration much less than a microsecond. The report provides information on certain precautions and the selection of calibration constants needed to permit the use of methods of dosimetry employed for measuring continuous radiation from constant potential x-ray sources or from gamma-ray sources. Treated are measurements using ionization chambers, chemical dosimeters, calorimeters and solid state devices. The aim of the report is to guide those who have to measure pulsed radiation to the most convenient and accurate system for their particular problem.

Not Available

1983-01-01

329

Measurement of solar radiation  

SciTech Connect

There is provided a device for indicating the level of solar radiation intensity, and especially that region of the spectrum in the ultraviolet region which causes sunburn. The device may be provided with an output subdivided into a plurality of discrete levels of intensity indicated as numerals and figures. It may be provided with means of adjustment to the physiology of the user.

Braunstein, A.; Levite, T.; Sohar, E.

1984-11-27

330

Underwater Radiation Detector.  

National Technical Information Service (NTIS)

A detector apparatus for differentiating between gamma and neutron radiation is provided. The detector includes a pair of differentially shielded Geiger-Mueller tubes. The first tube is wrapped in silver foil and the second tube is wrapped in lead foil. B...

L. W. Kruse R. P. McKnight

1984-01-01

331

Photovoltaic radiation detector element  

DOEpatents

A radiation detector element is formed of a body of semiconductor material, a coating on the body which forms a photovoltaic junction therewith, and a current collector consisting of narrow metallic strips, the aforesaid coating having an opening therein the edge of which closely approaches but is spaced from the current collector strips.

Agouridis, Dimitrios C. (Oak Ridge, TN)

1983-01-01

332

SHIELDING AGAINST SPACE RADIATION  

Microsoft Academic Search

A discussion of the problems in space radiation shielding is presented. ; The problem of penetrating protons is considered in an attempt to iliustrate the ; physical shieiding requirements for manned vehicles and to illuminate some of the ; gaps in present knowledge. Material and magnetic shielding are considered. ; (C.E.S.);

Madey

1963-01-01

333

Nuclear Radiation Damages Minds!  

ERIC Educational Resources Information Center

|Professors Ernest Sternglass (University of Pittsburgh) and Steven Bell (Berry College) have assembled cogent, conclusive evidence indicating that nuclear radiation is associated with impaired cognition. They suggest that Scholastic Aptitude Scores (SATs), which have declined steadily for 19 years, will begin to rise. Their prediction is based on

Blai, Boris, Jr.

334

An Inexpensive Radiation Counter.  

ERIC Educational Resources Information Center

|Describes a radiation counter comparable to commercial units which costs less than $100. It consists of six sections: Geiger-Mueller tube and holder; high voltage supply; low voltage supply; pulse shaping circuit; "start/stop counts" gating circuit; and counter/display. List of materials needed and schematic diagrams are included. (JN)|

Holton, Brian; Balla, Zsolt

1985-01-01

335

Chronic Radiation Enteritis  

Microsoft Academic Search

LEARNING OUTCOME: To identify foods that commonly affect bowel activity after abdominal radiotherapy.Chronic Radiation Enteritis (CRE) can occur in patients who receive abdominal radiotherapy (ART). The literature suggests low residue, low fat, and low lactose diets in the management of CRE symptoms but does not provide definitive guidelines. Twenty-six women with documented CRE and 21 with no documentation of CRE

S. K. Sekhon

1997-01-01

336

Thermodynamics of Radiation Modes  

ERIC Educational Resources Information Center

|We study the equilibrium thermodynamics of the electromagnetic radiation in a cavity of a given volume and temperature. We found three levels of description, the thermodynamics of one mode, the thermodynamics of the distribution of frequencies in a band by summing over the frequencies in it and the global thermodynamics by summing over all the

Pina, Eduardo; de la Selva, Sara Maria Teresa

2010-01-01

337

IONIZING RADIATION OF EGGS  

Technology Transfer Automated Retrieval System (TEKTRAN)

Contamination of eggs and egg products by Salmonella is associated with a significant number of illnesses in the U.S. each year. Ionizing radiation can inactivate Salmonella on the egg surface, in the egg white, and in the yolk of shell eggs, and has been approved by the U.S. FDA at doses up to 3.0...

338

Hawking Radiation As Tunneling  

Microsoft Academic Search

We present a short and direct derivation of Hawking radiation as a tunneling process, based on particles in a dynamical geometry. The imaginary part of the action for the classically forbidden process is related to the Boltzmann factor for emission at the Hawking temperature. Because the derivation respects conservation laws, the exact spectrum is not precisely thermal. We compare and

Maulik K. Parikh; Frank Wilczek

2000-01-01

339

EXPERIMENTAL PERSONNEL RADIATION DOSIMETERS  

Microsoft Academic Search

Two experimental pocket-size radiation dosimeters were developed to ; provide either an indicated measurement of accumulated dose or suitable alarming ; for preselected dose levels. One audibly alarms after a predetermined dose is ; accumulated. The second provides digital indication of the received dose on a ; miniature register. Both are adaptable to radiotelemetry methods of information ; transfer. The

D. P. Brown; M. O. Rankin

1962-01-01

340

Radiation Patterns of Lightning  

Microsoft Academic Search

New Mexico Tech's Lightning Mapping Array (LMA) uses time-of-arrival measurements at a network of stations to accurately locate VHF radiation sources in three spatial dimensions and time. The peak power values are also measured at each station but have not been fully utilized. Currently the source power calculations assume an isotropic source and an isotropic receiver gain pattern. The event

J. D. Harlin; P. R. Krehbiel; X. Shao; R. J. Thomas

2007-01-01

341

Distributed Robotic Radiation Mapping  

Microsoft Academic Search

We develop a control scheme to coordinate a group of mobile sensors for radiation mapping of a given planar polygon region. The control algorithm is based on the concept of information surfing, where navigation is done by means of following information gradients, taking into account sensing perfor- mance as well as dynamics of the observed process. The control scheme steers

R. Andres Cortez; Herbert G. Tanner; Ron Lumia

2008-01-01

342

Paradoxes of Thermal Radiation  

ERIC Educational Resources Information Center

|This paper presents an analysis of the thermal behaviour of objects exposed to a solar-type flux of thermal radiation. It aims to clarify certain apparent inconsistencies between theory and observation, and to give a detailed exposition of some critical points that physics textbooks usually treat in an insufficient or incorrect way. In

Besson, U.

2009-01-01

343

TRANSISTORIZED RADIATION MONITORS  

Microsoft Academic Search

Paper presented at I.R.E. Professional Group on Nuclear Science ; Meeting, New York, Oct. 3l, l957. The advantages of transistors over vacuum ; tubes in radiation instruments have long been realized but a somewhat different ; approach to circuit design must be followed in developing transistor instruments, ; as compared with that used in vacuum tube circuits, and this seems

Goulding

1957-01-01

344

Transistorized Radiation Monitors  

Microsoft Academic Search

The advantages of transistors over vacuum tubes in radiation instruments have long been realized but a somewhat different approach to circuit design must be followed in developing transistor instruments, as compared with that used in vacuum tube circuits, and this seems to have discouraged many from developing such circuits. The purpose of this paper is to describe in some detail

F. S. Goulding

1958-01-01

345

VDT Emissions Radiate Debate.  

ERIC Educational Resources Information Center

|Discusses the possible health effects of electromagnetic fields of radiation that are emitted from video display terminals (VDTs). Responses from vendors in the computer industry are related, steps to reduce possible risks are suggested, and additional sources of information on VDTs are listed. (LRW)|

Morgan, Bill

1990-01-01

346

Psoriasis and ultraviolet radiation  

SciTech Connect

Prevention and detection screening programs as a public health service in curtailing the ever-increasing incidence of all forms of skin cancer are reviewed. The effect of solar and artificial ultraviolet radiation on the general population and persons with psoriasis is examined. 54 refs.

Farber, E.M.; Nall, L. (Psoriasis Research Institute, Palo Alto, CA (United States))

1993-09-01

347

ATMOSPHERIC RADIATION MEASUREMENT PROGRAM  

EPA Science Inventory

The Atmospheric Radiation Measurement Program (ARM) is the largest global change research program supported by the U.S. Department of Energy (DOE). ARM scientists focus on obtaining field measurements and developing models to better understand the processes that control solar and...

348

Radiation: Balancing the Record  

Microsoft Academic Search

This article reviews the radioactivity experiments performed on humans during the cold war, and examines the ethics of the experiments. The radiation experiments can be broadly classified into three groups: researchers knowingly inflicted potential harm, using methods questionable even by the then-current standards; the investigations involved good work by any standards with appropriate safeguards taken; and a third group which

Charles C. Mann

1994-01-01

349

Radiation Therapy Oncology Group  

MedlinePLUS

... to be Showcased at ASTRO 2013 RTOG Investigator William Small, Jr, MD, Named Gynecologic Cancer Intergroup Chair-Elect and Radiation Oncology Dept. Chair at Loyola University Remembrances of RTOG Investigator Kian Ang, MD, PhD Copyright (c) 2013 RTOG | Privacy Statement | Login RTOG is funded ...

350

Upwelling Terrestrial Radiation  

NSDL National Science Digital Library

The Stefan-Boltzmann Law is a fundamental law of physics. In this lesson, students will use this law and the near-ground air temperature to compute the hourly irradiance emitted by the surface of Earth. Then comparisons will be made with actual observations of this variable, called upwelling terrestrial radiation.

351

Thermodynamics of Radiation Modes  

ERIC Educational Resources Information Center

We study the equilibrium thermodynamics of the electromagnetic radiation in a cavity of a given volume and temperature. We found three levels of description, the thermodynamics of one mode, the thermodynamics of the distribution of frequencies in a band by summing over the frequencies in it and the global thermodynamics by summing over all the

Pina, Eduardo; de la Selva, Sara Maria Teresa

2010-01-01

352

VDT Emissions Radiate Debate.  

ERIC Educational Resources Information Center

Discusses the possible health effects of electromagnetic fields of radiation that are emitted from video display terminals (VDTs). Responses from vendors in the computer industry are related, steps to reduce possible risks are suggested, and additional sources of information on VDTs are listed. (LRW)

Morgan, Bill

1990-01-01

353

Radiation and immunotherapy  

PubMed Central

Anticancer immunotherapy holds great promises, as long-term responses to interleukin-2 have been observed in metastatic melanoma and renal cell carcinoma patients. However, improving the relative low rates of such responses has constituted a great challenge. In our experience, high-dose radiation combined with interleukin-2 provided encouraging results that are worth exploring further.

Seung, Steven K.; Curti, Brendan; Crittenden, Marka; Urba, Walter

2012-01-01

354

Radiation therapy for gliomas  

Microsoft Academic Search

Radiotherapy remains one of the cornerstones of treatment of patients with gliomas. Radiation- induced damage to DNA can result in the loss of proliferative capacity of neoplastic cells. In addition to mitotic cell death, it has recently been found that other cellular events can lead to reproductive failure. Apoptosis, or programmed cell death, has been described as a response to

Edward G. Soltesz; Abel Jaramillo; Frederick A. Tibayan; Peter M. Black

1999-01-01

355

Acute Radiation Nephritis.  

National Technical Information Service (NTIS)

Three cases of acute radiation nephritis have been reported. All 3 patients died within 8 months after radiotherapy to the kidney area, 2 with symptoms of renal failure and the third from other causes. All 3 showed similar renal lesions at autopsy. Pathol...

F. K. Mostofi

1964-01-01

356

Continuum radiation at Uranus  

Microsoft Academic Search

Uranus has proven to be a radio source of remarkable complexity with as many as six distinctly different types of emission. One Uranian radio emission which has thus far escaped attention is an analog of continuum radiation at Earth, Jupiter, and Saturn. The emission is found to be propagating in the ordinary mode in the range of one to a

W. S. Kurth; D. A. Gurnett; M. D. Desch

1990-01-01

357

Manifolds and Radiation Protection  

NASA Astrophysics Data System (ADS)

During the past 40 years humans have travelled beyond Earth's atmosphere, orbiting the planets for extended periods of time and landing on the Moon. Humans have survived this overwhelming challenge but to assure future exploration of space further expertise in the long term survival in space must be obtained. The International Space Station (ISS) provides this opportunity and allows space scientist to fine-tune their knowledge and prepare for even bolder human space missions. In this work we focus on the aspect of radiation, perhaps the most complex one from a physical and physiological perspective. Travel beyond the Earth's atmosphere and especially to Moon and Mars requires a precise consideration of the radiation environment as radiation exposure could be a show-stopper. At the moment scientists have not yet developed complete and reliable systems for radiation protection. Most likely an adequate level of protection will be reached through an integrated countermeasure system which could include: shields, monitoring of the environment, drugs to protect from damage, etc.

Rossitto, Franco; Petrov, Vladislav M.; Ongaro, Filippo

358

Infrared radiation: Herschel revisited  

Microsoft Academic Search

The year 2000 marks the 200th anniversary of Herschel's discovery of infrared radiation. Using a car light in place of the Sun and a liquid crystal sheet instead of thermometers, the experiment is an effective classroom demonstration of invisible light.

Erin E. Pursell; Richard Kozlowski

2000-01-01

359

Solar radiative energy  

NASA Astrophysics Data System (ADS)

Solar radiation conversion into heat, and electrical and chemical energy is discussed. The theoretical limits of energy conservation along these conversion paths are considered. Thermal conversion is improved by use of optically selective absorbers. There are fundamental analogies between photovoltaics, photochemical and (optically selective) photothermal processes. Natural photosynthesis is taken as an example for a balance of energy yield from solar irradiance.

Sizmann, R.

1985-11-01

360

Justification in Radiation Protection  

Microsoft Academic Search

In recent years the concept of Justification has increasingly come to the fore of the minds of legislators, users of radioactive materials and radiation protection specialists alike. Perhaps the most well known manifestation of this was the lengthy debate, ending in judicial review, about the Justification for the operation of the Thermal Oxide Reprocessing Plant (Thorp) at Sellafield and, more

David Owen

1999-01-01

361

Ionizing radiation from tobacco  

SciTech Connect

Accidents at nuclear power facilities seem inevitably to bring in their wake a great deal of concern on the part of both the lay and medical communities. Relatively little attention, however, is given to what may be the largest single worldwide source of effectively carcinogenic ionizing radiation: tobacco. The risk of cancer deaths from the Chernobyl disaster are tobacco smoke is discussed.

Westin, J.B.

1987-04-24

362

Note on the radiation between two coaxial radiating cylinders  

Microsoft Academic Search

The paper discusses the problem of the radiation transfer from an electrically heated inner cylinder to a surrounding coaxial cylinder. Expressions are derived for the total radiation, emitted and reflected, from unit area of each of the cylindrical surfaces between which multiple reflection of radiation occurs. It is then shown how, from these expressions, the relation of the true temperatures

H. Buckley

1937-01-01

363

SSC environmental radiation shielding  

SciTech Connect

The environmental radiation shielding requirements of the SSC have been evaluated using currently available computational tools that incorporate the well known processes of energy loss and degradation of high energy particles into Monte Carlo computer codes. These tools permit determination of isodose contours in the matter surrounding a source point and therefore the specification of minimum thicknesses or extents of shielding in order to assure annual dose equivalents less than some specified design amount. For the general public the annual dose equivalent specified in the design is 10 millirem, small compared to the dose from naturally occurring radiation. The types of radiation fall into two classes for the purposes of shielding determinations-hadrons and muons. The sources of radiation at the SSC of concern for the surrounding environment are the interaction regions, the specially designed beam dumps into which the beams are dumped from time to time, and beam clean-up regions where stops remove the beam halo in order to reduce experimental backgrounds. A final, unlikely source of radiation considered is the accidental loss of the full beam at some point around the ring. Conservative choices of a luminosity of 10{sup 34} cm{sup {minus}2}s{sup {minus}1} and a beam current three times design have been made in calculating the required shielding and boundaries of the facility. In addition to determination of minimum distances for the annual dose equivalents, the question of possible radioactivity produced in nearby wells or in municipal water supplies is addressed. The designed shielding distances and beam dumps are such that the induced radioactivity in ground water is safely smaller than the levels permitted by EPA and international agencies.

Jackson, J.D. [ed.

1987-07-01

364

Radiation resistance of integrated microcircuits  

NASA Astrophysics Data System (ADS)

The effects of ionizing radiation on bipolar and MOS integrated circuits are investigated. Various models of typical integrated structures are examined, and the maximum radiation resistance of different classes of integrated microcircuits is calculated.

Agakhanian, T. M.; Astvatsaturian, E. R.; Skorobogatov, P. K.; Chumakov, A. I.

1980-06-01

365

Chemical Protection Against Ionizing Radiation.  

National Technical Information Service (NTIS)

The scientific literature on radiation-protective drugs is reviewed. Emphasis is placed on the mechanisms involved in determining the sensitivity of biological material to ionizing radiation and mechanisms of chemical radioprotection. In Section I, the ty...

J. C. Livesey D. J. Reed L. F. Adamson

1984-01-01

366

Radiation of a perforated cylinder  

Microsoft Academic Search

The generalized zonal method is used to find the energy radiated by a perforated cylinder. The existence of a range of geometric optical parameters is established, where in the perforated cylinder radiates more energy than a continuous cylinder.

A. V. Rumyantsev; O. N. Bryukhanov; V. E. Fedyanin

1978-01-01

367

Radiation Risk From Medical Imaging  

PubMed Central

This review provides a practical overview of the excess cancer risks related to radiation from medical imaging. Primary care physicians should have a basic understanding of these risks. Because of recent attention to this issue, patients are more likely to express concerns over radiation risk. In addition, physicians can play a role in reducing radiation risk to their patients by considering these risks when making imaging referrals. This review provides a brief overview of the evidence pertaining to low-level radiation and excess cancer risks and addresses the radiation doses and risks from common medical imaging studies. Specific subsets of patients may be at greater risk from radiation exposure, and radiation risk should be considered carefully in these patients. Recent technical innovations have contributed to lowering the radiation dose from computed tomography, and the referring physician should be aware of these innovations in making imaging referrals.

Lin, Eugene C.

2010-01-01

368

RADIATION ENVIRONMENT OF GROWTH CHAMBERS  

EPA Science Inventory

Radiation measurements with different types of meters in several controlled environment facilities have been compiled to demonstrate the problems associated with insuring uniform radiation levels in separate facilities. Data are provided for a quantum meter, three photometers, a ...

369

Gamma radiation field intensity meter  

DOEpatents

A gamma radiation intensity meter measures dose rate of a radiation field. The gamma radiation intensity meter includes a tritium battery emitting beta rays generating a current which is essentially constant. Dose rate is correlated to an amount of movement of an electroscope element charged by the tritium battery. Ionizing radiation decreases the voltage at the element and causes movement. A bleed resistor is coupled between the electroscope support element or electrode and the ionization chamber wall electrode. 4 figs.

Thacker, L.H.

1995-10-17

370

Common Features of Killer Apps: A Comparison with Prot' eg' e  

Microsoft Academic Search

Abstract. Killer apps are highly transformative technologies that create new markets and widespread pat-terns of behaviour. IT generally, and the Web in particular, has benefited from killer apps creating new networks of users. The Semantic Web community on the other hand, is still unsure whether any of their applications could become a killer app. This paper sheds some light on

Harith Alani; Kieron O'hara; Nigel Shadbolt

371

WebProt?g?: A Collaborative Ontology Editor and Knowledge Acquisition Tool for the Web  

PubMed Central

In this paper, we present WebProtga lightweight ontology editor and knowledge acquisition tool for the Web. With the wide adoption of Web 2.0 platforms and the gradual adoption of ontologies and Semantic Web technologies in the real world, we need ontology-development tools that are better suited for the novel ways of interacting, constructing and consuming knowledge. Users today take Web-based content creation and online collaboration for granted. WebProtg integrates these features as part of the ontology development process itself. We tried to lower the entry barrier to ontology development by providing a tool that is accessible from any Web browser, has extensive support for collaboration, and a highly customizable and pluggable user interface that can be adapted to any level of user expertise. The declarative user interface enabled us to create custom knowledge-acquisition forms tailored for domain experts. We built WebProtg using the existing Protg infrastructure, which supports collaboration on the back end side, and the Google Web Toolkit for the front end. The generic and extensible infrastructure allowed us to easily deploy WebProtg in production settings for several projects. We present the main features of WebProtg and its architecture and describe briefly some of its uses for real-world projects. WebProtg is free and open source. An online demo is available at http://webprotege.stanford.edu.

Tudorache, Tania; Nyulas, Csongor; Noy, Natalya F.; Musen, Mark A.

2012-01-01

372

Carcinoma of the anal canal: radiation or radiation plus chemotherapy  

SciTech Connect

An editorial is presented which discusses the treatment of carcinoma of the anal canal. Following the initial report of the successful preoperative use of combined chemotherapy and radiation by Nigro in 1974, several centers have confirmed the effectiveness of such combinations either as preoperative or as definitive treatment of anal carcinomas, and many patients are now being referred for radiation therapy. The article by Cantril in this issue describe the successful treatment of anal carcinomas by radiation alone, and raises the important issue of whether radiation plus chemotherapy is more effective treatment than radiation alone for squamous or cloacogenic carcinomas arising in the anal canal or perianal area. Several studies are cited.

Cummings, B.J.

1983-09-01

373

UV Radiation Climatology and Trends  

Microsoft Academic Search

The global distribution of erythemally weighted UV radiation and its seasonal changes are compared with the corresponding trends due to changing atmospheric composition. Because of the success of the Montreal Protocol, the trends in UV radiation have been relatively small outside the regions directly affected by the Antarctic ozone Hole. We do not expect further large increases in UV radiation

Richard L. McKenzie

374

Radiation effect on implanted pacemakers  

SciTech Connect

It was previously thought that diagnostic or therapeutic ionizing radiation did not have an adverse effect on the function of cardiac pacemakers. Recently, however, some authors have reported damaging effect of therapeutic radiation on cardiac pulse generators. An analysis of a recently-extracted pacemaker documented the effect of radiation on the pacemaker pulse generator.

Pourhamidi, A.H.

1983-10-01

375

Future status of radiation breeding  

Microsoft Academic Search

The induction of artifical mutations by radiation and its utilization ; for radiation breeding are discussed. There are external and internal ; irradiation methods to induce mutations by radiation. The former method has the ; advantage of good reproducibility and occupies the main current. In the latter ; method, the rate of mutation per rate of dose unit is high

Tanaka

1973-01-01

376

SPS transmitting antenna radiation pattern  

Microsoft Academic Search

It is essential that the power densities produced on earth by the solar powered satellite (SPS) radiated beam be calculated exactly. The radiation pattern corresponding to the idealized illumination law is not sufficiently accurate. A method for computing the actual pattern of the radiation beam is described. Further work is necessary and provisions must be made for random disturbances and

Combes

1981-01-01

377

Solar radiation statistics for Iran  

Microsoft Academic Search

Various prediction methods for calculating the mean monthly solar radiation parameters are examined. A suitable method is proposed for predicting the mean monthly values of direct, diffuse, and total solar radiation at different locations in Iran. This method is based on the assumption that the direct and diffuse components of solar radiation are primarily functions of solar zenith angle and

M DANESHYAR

1978-01-01

378

Meson Production and Space Radiation  

Microsoft Academic Search

Protecting astronauts from the harmful effects of space radiation is an important priority for long duration space flight. The National Council on Radiation Protection (NCRP) has recently recommended that pion and other mesons should be included in space radiation transport codes, especially in connection with the Martian atmosphere. In an interesting accident of nature, the galactic cosmic ray spectrum has

John Norbury; Steve Blattnig; Ryan Norman; Sukesh Aghara

2010-01-01

379

Martian Radiation Environment Experiment (MARIE)  

Microsoft Academic Search

Space radiation presents a very serious hazard to crews of interplanetary human missions. The two sources of this radiation are the galactic cosmic rays (GCR) and solar energetic particle (SEP) events. The GCR provides a steady source of low dose rate radiation that is primarily responsible for stochastic effects, such as cancer, and can effect the response of the central

Gautam D. Badhwar

1999-01-01

380

Radiation effects on integrated microcircuits  

NASA Astrophysics Data System (ADS)

A theory describing the effects of ionizing radiation on integrated microcircuits is developed. The features of secondary ionization effects (e.g., radiation-induced secondary breakdown) are examined along with residual and transient ionization effects on the characteristics of standard components of digital and analog ICs. The radiation characteristics of LSI systems are also considered, with emphasis on microdosimetric and functional effects.

Agakhanian, Tatevos M.; Astvatsatur'ian, Evgenii R.; Skorobogatov, Petr K.

381

Video Display Terminals: Radiation Issues.  

ERIC Educational Resources Information Center

|Discusses information gathered in past few years related to health effects of video display terminals (VDTs) with particular emphasis given to issues raised by VDT users. Topics covered include radiation emissions, health concerns, radiation surveys, occupational radiation exposure standards, and long-term risks. (17 references) (EJS)|

Murray, William E.

1985-01-01

382

Scientific balloon effective radiative properties  

Microsoft Academic Search

Prediction of the flight performance of a scientific balloon is dependent on the radiative properties of the balloon. To determine its optical properties for use in performance calculations, the balloon must be viewed as a composite structure. Determination of the balloon's effective radiative properties takes into account the shape, the orientation to radiative sources, and the construction of the balloon

H. M. Cathey

1998-01-01

383

Self Indicating Radiation Alert Dosimeter.  

National Technical Information Service (NTIS)

Described as a self-indicating instant radiation dosimeter for monitoring high energy radiations, such as X-ray. The dosimeter contains a radiation sensitive, color changing, indicating composition, e.g., a diacetylene (R--C=C--C=C--R', where R and R' are...

G. N. Patel

2004-01-01

384

Cataracts and personal communication radiation  

Microsoft Academic Search

The induction of cataracts or formation of lens opacity in the human eye has often been incriminated as a possible hazard of human exposure to personal communication radiation and microwave radiation in general. In the case of cell phones, some concerns have been expressed when the user holds the cell-phone handset, or the microwave radiating device, directly in front of

L. C. Lin

2003-01-01

385

Synchrotron radiation - 1873 to 1947  

Microsoft Academic Search

In 1873 Maxwell's treatise ``Electricity and Magnetism'' made it clear that a changing electric current will emit electromagnetic radiation. By the turn of the century, J.J. Thomson was showing that currents in space could be carried by electrons; accordingly, it was reasonable to believe that electrons, when accelerated, would radiate. By 1912, the theory of radiation from accelerated electrons was

John P. Blewett

1988-01-01

386

Angular momentum of synchrotron radiation  

NASA Astrophysics Data System (ADS)

Exact methods of the theory of relativistic radiation of an arbitrarily moving charge provide the basis for the theory of radiation of the angular momentum of an electromagnetic field stated here. As an application, properties of orbital and spin angular momenta of synchrotron radiation are considered.

Bordovitsyn, V. A.; Konstantinova, O. A.; Nemchenko, E. A.

2012-06-01

387

Pregnancy and Radiation Protection  

SciTech Connect

Several modalities are currently utilized for diagnosis and therapy, by appropriate application of x-rays. In diagnostic radiology, interventional radiology, radiotherapy, interventional cardiology, nuclear medicine and other specialties radiation protection of a pregnant woman as a patient, as well as a member of the operating personnel, is of outmost importance. Based on radiation risk, the termination of pregnancy is not justified if foetal doses are below 100 mGy. For foetal doses between 100 and 500 mGy, a decision is reached on a case by case basis. In Diagnostic Radiology, when a pregnant patient takes an abdomen CT, then an estimation of the foetus' dose is necessary. However, it is extremely rare for the dose to be high enough to justify an abortion. Radiographs of the chest and extremities can be done at any period of pregnancy, provided that the equipment is functioning properly. Usually, the radiation risk is lower than the risk of not undergoing a radiological examination. Radiation exposure in uterus from diagnostic radiological examinations is unlikely to result in any deleterious effect on the child, but the possibility of a radiation-induced effect can not be entirely ruled out. The effects of exposure to radiation on the foetus depend on the time of exposure, the date of conception and the absorbed dose. Finally, a pregnant worker can continue working in an x-ray department, as long as there is reasonable assurance that the foetal dose can be kept below 1 mGy during the pregnancy. Nuclear Medicine diagnostic examinations using short-lived radionuclides can be used for pregnant patient. Irradiation of the foetus results from placental transfer and distribution of radiopharmaceuticals in the foetal tissues, as well as from external irradiation from radioactivity in the mother's organ and tissues. As a rule, a pregnant patient should not undergo therapy with radionuclide, unless it is crucial for her life. In Radiotherapy, the patient, treating oncologist, other team and family members should carefully discuss for the decision of abortion. Important factors must be considered such as the stage and aggressiveness of the tumour, the location of the tumour, the stage of pregnancy, various therapies etc.

Gerogiannis, J. [Nicosia General Hospital, Nicosia (Cyprus); Stefanoyiannis, A. P. [University General Hospital of Athens 'Attikon', Athens (Greece)

2010-01-21

388

The Fukushima radiation accident: consequences for radiation accident medical management.  

PubMed

The March 2011 radiation accident in Fukushima, Japan, is a textbook example of a radiation accident of global significance. In view of the global dimensions of the accident, it is important to consider the lessons learned. In this context, emphasis must be placed on consequences for planning appropriate medical management for radiation accidents including, for example, estimates of necessary human and material resources. The specific characteristics of the radiation accident in Fukushima are thematically divided into five groups: the exceptional environmental influences on the Fukushima radiation accident, particular circumstances of the accident, differences in risk perception, changed psychosocial factors in the age of the Internet and globalization, and the ignorance of the effects of ionizing radiation both among the general public and health care professionals. Conclusions like the need for reviewing international communication, interfacing, and interface definitions will be drawn from the Fukushima radiation accident. PMID:22951483

Meineke, Viktor; Drr, Harald

2012-08-01

389

10 CFR 39.67 - Radiation surveys.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Radiation surveys. 39.67 Section 39.67...COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Radiation Safety Requirements § 39.67 Radiation surveys. (a) The licensee shall...

2010-01-01

390

10 CFR 34.49 - Radiation surveys.  

Code of Federal Regulations, 2010 CFR

...2010-01-01 false Radiation surveys. 34.49 Section 34...INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL...RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.49 Radiation surveys. The licensee shall:...

2010-01-01

391

10 CFR 34.49 - Radiation surveys.  

Code of Federal Regulations, 2010 CFR

...2009-01-01 false Radiation surveys. 34.49 Section 34...INDUSTRIAL RADIOGRAPHY AND RADIATION SAFETY REQUIREMENTS FOR INDUSTRIAL...RADIOGRAPHIC OPERATIONS Radiation Safety Requirements § 34.49 Radiation surveys. The licensee shall:...

2009-01-01

392

10 CFR 39.67 - Radiation surveys.  

Code of Federal Regulations, 2010 CFR

...2009-01-01 false Radiation surveys. 39.67 Section 39.67...COMMISSION LICENSES AND RADIATION SAFETY REQUIREMENTS FOR WELL LOGGING Radiation Safety Requirements § 39.67 Radiation surveys. (a) The licensee shall...

2009-01-01

393

29 CFR 1910.97 - Nonionizing radiation.  

Code of Federal Regulations, 2010 CFR

...Nonionizing radiation. (a) Electromagnetic radiation (1) Definitions...paragraph. (i) The term electromagnetic radiation is restricted to...other possible sources of electromagnetic radiation such as used for...

2009-07-01

394

29 CFR 1910.97 - Nonionizing radiation.  

Code of Federal Regulations, 2010 CFR

...Nonionizing radiation. (a) Electromagnetic radiation (1) Definitions...paragraph. (i) The term electromagnetic radiation is restricted to...other possible sources of electromagnetic radiation such as used for...

2010-07-01

395

Sarcoma - Adult Soft Tissue Cancer: Radiation Therapy  

MedlinePLUS

... sarcomas Next Topic Chemotherapy for soft tissue sarcomas Radiation therapy for soft tissue sarcomas Radiation therapy uses ... spread. This is called palliative treatment. Types of radiation therapy External beam radiation therapy: For this treatment, ...

396

Mullichannel radiography employing scattered radiation  

SciTech Connect

A diagnostic imaging system and process permits construction of an image of an area of an interfacial surface within the body of a subject, such as the heart-lung interface. The imaging system includes radiation source means for generating a shaped beam of penetrating radiation for illuminating the interfacial surface. Radiation scattered from tissue at the interface is detected by a plurality of directional radiation detectors which can be automatically positioned and oriented so that their fields of view intersect the beam of radiation and the interfacial surface.

Jacobs, A. M.; Kenney, E. S.; McInerney, J. J.

1985-01-22

397

Relativistic coherent curvature radiation  

NASA Astrophysics Data System (ADS)

The objections raised by Kirk (1980) to the formalism describing the coherent curvature radiation of charged particles proposed by Benford and Buschauer (1977) are examined. It is shown that Kirk's results arise from qualitative calculations of boundary effects. Exact calculations are presented which show that the non-curvature radiation comes from the body of the plasma due to the longitudinal acceleration it is experiencing. In general, it is found that the introduction of moving plasma waves into relativistic systems will increase the emitted power and broaden the spectrum. These results are applicable to the coherent radio pulsar emission which may come from plasma columns moving along the curved magnetic fields lines of pulsar magnetospheres.

Benford, G.; Buschauer, R.

1983-02-01

398

Biochemistry of ionizing radiation  

SciTech Connect

This volume examines the biochemical changes occurring in normal tissue after irradiation. A review of radiation chemistry is followed by an analysis of factors affecting biochemical responses and a timely discussion of radiobiology in space flight. The authors then describe the effects of radiation on lipid peroxidation, amino acids, peptides, proteins, polysaccharides, DNA, thiols, and body fluids. Close attention is given to alterations in biological mediators such as eicosanoids, cyclic nucleotides, angiotensin, histamine, polyamines, catecholamines, and serotonin and in hormones such as adrenocorticotropic hormone, testosterone, estrogens, follicle-stimulating hormone, luteinizing hormone, thyroid hormones, insulin and glucagon, gastrin, and melatonin. Other chapters focus on changes in carbohydrate metabolism, oxidative phosphorylation, protein synthesis, and serum proteins. A chapter on biological dosimeters discusses prodromal syndrome, hematological dosimeters, serum composition, urine, chromosomal aberrations, and fluorometric and immunoassays.

Walden, T.L.; Nushin, F.K.

1990-01-01

399

Accepting space radiation risks.  

PubMed

The human exploration of space inevitably involves exposure to radiation. Associated with this exposure are multiple risks, i.e., probabilities that certain aspects of an astronaut's health or performance will be degraded. The management of these risks requires that such probabilities be accurately predicted, that the actual exposures be verified, and that comprehensive records be maintained. Implicit in these actions is the fact that, at some point, a decision has been made to accept a certain level of risk. This paper examines ethical and practical considerations involved in arriving at a determination that risks are acceptable, roles that the parties involved may play, and obligations arising out of reliance on the informed consent paradigm seen as the basis for ethical radiation risk acceptance in space. PMID:20414667

Schimmerling, Walter

2010-04-23

400

First infrared radiation detector  

SciTech Connect

The first in the world noncooled photon detector designed for the detection of infrared radiation of wave length 8-12 micrometers (optimized wave length 10.6 micrometers) has been manufactured in the Plasma Physics and Laser Microsynthesis Institute, in close cooperation with the Technical Military Academy. The father of the technology is Professor Piotrowski from the Technical Military Academy while the construction and idea of utilization of the new instrument stem from the Plasma Physics and Laser Microsynthesis Institute in Warsaw. The elaboration of a new and really sensational technology was the logical outcome of research work carried out in Poland on cadmium-mercury telluride. And it was just on the basis of that new semiconductor that the noncooled infrared radiation detector has been constructed.

Not Available

1984-03-01

401

TOPEX orbital radiation study  

SciTech Connect

The space radiation environment of the TOPEX spacecraft is investigated. A single trajectory was considered. The external (surface incident) charged particle radiation, predicted for the satellite, is determined by orbital flux integration for the specified trajectory. The latest standard models of the environment are used in the calculations. The evaluation is performed for solar maximum conditions. The spacecraft exposure to cosmic rays of galactic origin is evaluated over its flight path through the magnetosphere in terms of geomagnetic shielding effects, both for surface incident heavy ions and for particles emerging behind different material thickness. Limited shielding and dose evaluations are performed for simple infinite slab and spherical geometries. Results, given in graphical and tabular form, are analyzed, explained, and discussed. Conclusions are presented and commented on.

Stassinopoulos, E.G.; Barth, J.M.

1984-04-01

402

Quality in radiation oncology  

SciTech Connect

A modern approach to quality was developed in the United States at Bell Telephone Laboratories during the first part of the 20th century. Over the years, those quality techniques have been adopted and extended by almost every industry. Medicine in general and radiation oncology in particular have been slow to adopt modern quality techniques. This work contains a brief description of the history of research on quality that led to the development of organization-wide quality programs such as Six Sigma. The aim is to discuss the current approach to quality in radiation oncology as well as where quality should be in the future. A strategy is suggested with the goal to provide a threshold improvement in quality over the next 10 years.

Pawlicki, Todd; Mundt, Arno J. [Department of Radiation Oncology, University of California, San Diego, La Jolla, California 92093 (United States)

2007-05-15

403

Radiation optic neuropathy  

SciTech Connect

Following surgery for pituitary adenoma, radiation therapy is an accepted treatment in reducing tumor recurrence. However, a potential therapeutic complication is delayed radionecrosis of perisellar neural structures, including the optic nerves and chiasm. This particular cause of visual loss, radiation optic neuropathy (RON), has not been emphasized in the ophthalmologic literature. Four cases of RON seen in the past five years are reported. Diagnostic criteria include: (1) acute visual loss (monocular or binocular), (2) visual field defects indicating optic nerve or chiasmal dysfunction, (3) absence of optic disc edema, (4) onset usually within three years of therapy (peak: 1-1 1/2 years), and (5) no computed tomographic evidence of visual pathway compression. Pathologic findings, differential diagnosis and therapy will be discussed in outlining the clinical profile of RON.

Kline, L.B.; Kim, J.Y.; Ceballos, R.

1985-08-01

404

Sector 30 collimator radiation  

SciTech Connect

The collimators at Sector 30 of the SLAC accelerator are designed to scrape off a significant fraction (e.g., {approximately}20%) of the SLC beam. The electromagnetic cascade shower that develops in the collimator, and in the scraper and waveguide downbeam, leads to very high radiation exposures of TV cameras (and other devices) located nearby. The collimator (point) source accounts for one-third of the dose and is best shielded by extending the radius of the copper scraper. Radiation from the waveguide accounts for the remaining two-thirds of the dose, and is difficult to shield since it is a line source. However, the spectrum from the waveguide is expected to be softer than that from the collimator. This paper discusses shielding of these sources.

Namito, Y. (Ship Research Inst., Tokyo (Japan)); Nelson, W.R.; Benson, E.

1990-02-22

405

Electromagnetic Radiation: On Trial  

NSDL National Science Digital Library

This activity introduces students to the properties of electromagnetic radiation in a variety of ways. For example, they put the different types of the electromagnetic radiation on trial, selecting the judge, prosecutor, defense counsel, and jury, and learning about electromagnetic energy by arguing the pros and cons of each wavelength. During this activity, students are introduced to the general properties of electromagnetic waves, learn to analyze the relation between the specific properties of waves and their position in the electromagnetic spectrum, and discuss methods used to detect and analyze different waves. Students also learn about scientists whose work contributed to our understanding of electromagnetic energy. Students are encouraged to use an electronic bulletin board to communicate with each other, posting insights, ideas, evidence and questions on electromagnetic energy.

2007-05-16

406

Multilayer radiation shield  

DOEpatents

A power generation system including: a generator including a rotor including a superconductive rotor coil coupled to a rotatable shaft; a first prime mover drivingly coupled to the rotatable shaft; and a thermal radiation shield, partially surrounding the rotor coil, including at least a first sheet and a second sheet spaced apart from the first sheet by centripetal force produced by the rotatable shaft. A thermal radiation shield for a generator including a rotor including a super-conductive rotor coil including: a first sheet having at least one surface formed from a low emissivity material; and at least one additional sheet having at least one surface formed from a low emissivity material spaced apart from the first sheet by centripetal force produced by the rotatable shaft, wherein each successive sheet is an incrementally greater circumferential arc length and wherein the centripetal force shapes the sheets into a substantially catenary shape.

Urbahn, John Arthur (Saratoga Springs, NY); Laskaris, Evangelos Trifon (Niskayuna, NY)

2009-06-16

407

Radiation shielding composition  

DOEpatents

A composition for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm.sup.3 and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile.

Quapp, William J. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

1998-01-01

408

Radiation shielding composition  

DOEpatents

A composition is disclosed for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm{sup 3} and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile. 5 figs.

Quapp, W.J.; Lessing, P.A.

1998-07-28

409

Radiation shielding composition  

DOEpatents

A composition for use as a radiation shield. The shield is a concrete product containing a stable uranium aggregate for attenuating gamma rays and a neutron absorbing component, the uranium aggregate and neutron absorbing component being present in the concrete product in sufficient amounts to provide a concrete having a density between about 4 and about 15 grams/cm.sup.3 and which will at a predetermined thickness, attenuate gamma rays and absorb neutrons from a radioactive material of projected gamma ray and neutron emissions over a determined time period. The composition is preferably in the form of a container for storing radioactive materials that emit gamma rays and neutrons. The concrete container preferably comprises a metal liner and/or a metal outer shell. The resulting radiation shielding container has the potential of being structurally sound, stable over a long period of time, and, if desired, readily mobile.

Quapp, William J. (Idaho Falls, ID); Lessing, Paul A. (Idaho Falls, ID)

2000-12-26

410

Radiation Effects in Zircon  

SciTech Connect

The widespread distribution of zircon in the continental crust, its tendency to concentrate trace elements, particularly lanthanides and actinides, its use in age-dating, and its resistance to chemical and physical degradation have made zircon the most important accessory mineral in geologic studies. Because zircon is highly refractory, it also has important industrial applications, including its use as a lining material in high-temperature furnaces. However, during the past decade, zircon has also been proposed for advanced technology applications, such as a durable material for the immobilization of plutonium or, when modified by ion-beam irradiation, as an optic waveguide material. In all of these applications, the change in properties as a function of increasing radiation dose is of critical importance. In this chapter, we summarize the state-of-knowledge on the radiation damage accumulation process in zircon.

Ewing, Rodney C.; Meldrum, Alkiviathes; Wang, L. M.; Weber, William J.; Corrales, Louis R.

2003-12-11

411

Radiofrequency and microwave radiation  

SciTech Connect

This paper deals with the controversy and disagreement surrounding the issue of harm from radiofrequency (RF) and microwaves. The radiation standards adopted by different countries are quite divergent with the least strict standard for microwave exposure differing from the most strict by a factor of 100. Among the most powerful sources of RF and microwave radiation are radar systems used for tracking and guidance purposes, as well as transmiters used in satellite communication systems. RF and microwaves are nonionizing because the energy of each photon is relatively low. Biological systems exposed to RF and microwaves acquire induced electric and magnetic fields which can be focused by a combination of high refractive index within an animal and convex body contours. The effects on animals and humans are summarized. (KRM)

Hileman, B.

1982-08-01

412

National Ambient Radiation Database  

SciTech Connect

The U.S. Environmental Protection Agency (EPA) recently developed a searchable database and website for the Environmental Radiation Ambient Monitoring System (ERAMS) data. This site contains nationwide radiation monitoring data for air particulates, precipitation, drinking water, surface water and pasteurized milk. This site provides location-specific as well as national information on environmental radioactivity across several media. It provides high quality data for assessing public exposure and environmental impacts resulting from nuclear emergencies and provides baseline data during routine conditions. The database and website are accessible at www.epa.gov/enviro/. This site contains (1) a query for the general public which is easy to use--limits the amount of information provided, but includes the ability to graph the data with risk benchmarks and (2) a query for a more technical user which allows access to all of the data in the database, (3) background information on ER AMS.

Dziuban, J.; Sears, R.

2003-02-25

413

Radiation resistance of Salmonella  

Microsoft Academic Search

Summary The ionizing radiation resistances of sixSalmonella species were examined. The experimental variables were the suspending medium, the presence or absence of air, and the temperature during the irradiation process.S. typhimurium ATCC 14028,S. enteritidis ATCC 9186,S. newport ATCC 6962,S. dublin ATCC 15480,S. anatum ATCC 9270, andS. arizonae ATCC 29933 were suspended in phosphate buffer (0.1 M, pH 7.0), brain heart

Donald W. Thayer; Glenn Boyd; Wayne S. Muller; Carol A. Lipson; Walter C. Hayne; Steven H. Baer

1990-01-01

414

The radiative cooling resource  

NASA Astrophysics Data System (ADS)

Results of an experimental infrared sky emissivity measurement program were combined with a method for estimating thermal radiation from clouds to develop an algorithm for calculating the effective sky temperature based on commonly recorded meteorological parameters. This algorithm is used with hourly weather data from 193 Typical Meteorological Year sites in the continental United States to produce contour maps and histograms for the sky temperature depression, and related resource information.

Martin, M.; Berdahl, P.

1983-11-01

415

Structure in Radiative Shocks  

NASA Astrophysics Data System (ADS)

Radiative shocks are shock waves fast enough that radiation from the shock-heated matter alters the structure of the shock. They are of fundamental interest to high-energy-density physics and also have applications throughout astrophysics. This poster will review the dimensionless parameters that determine structure in these shocks and will discuss recent experiments to measure such structure for strongly radiative shocks that are optically thin upstream and optically thick downstream. The shock transition itself heats mainly the ions. Immediately downstream of the shock, the ions heat the electrons and the electrons radiate, producing an optically thin cooling layer, followed by the downstream layer of warm, shocked material. The axial structure of these systems is of interest, because the transition from precursor through the cooling layer to the final state is complex and difficult to calculate. Their lateral structure is also of interest, as they seem likely to be subject to some variation on the Vishniac instability of thin layers. In our experiments to produce such shocks, laser ablation launches a Be plasma into a tube of Xe or Ar gas, at a velocity above 100 km/s. This drives a shock down the tube. Radiography provides fundamental information about the structure and evolution of the shocked material in Xe. Thomson scattering and pyrometry have provided data in Ar. We will summarize the available evidence regarding the properties of these shocks, and will discuss their connections to astrophysical cases. This research was sponsored by the National Nuclear Security Administration under the Stewardship Science Academic Alliances program through DOE Research Grants DE-FG52-07NA28058, DE-FG52-04NA00064, and other grants and contracts.

Drake, R. Paul; Visco, A.; Doss, F.; Reighard, A.; Froula, D.; Glenzer, S.; Knauer, J.

2008-05-01

416

Radiation-induced proctosigmoiditis  

Microsoft Academic Search

In a prospective study, 37 consecutive patients with radiation-induced proctosigmoiditis were randomized to receive a four-week course of either 3.0 g oral sulfasalazine plus 20 mg twice daily rectal prednisolone enemas (group I,N=18) or 2.0 g twice daily rectal sucralfate enemas plus oral placebo (group II,N=19). The two groups were comparable with respect to demographic features, duration of symptoms, and

R. Kochhar; F. Patel; S. C. Sharma; S. Ayyagari; R. Aggarwal; M. K. Goenka; B. D. Gupta; S. K. Mehta

1991-01-01

417

Solar Radiation Resource Information  

NSDL National Science Digital Library

This is the Solar Radiation Resource Information page for the RReDC which provides information on several types of renewable energy resources in the United States, in the form of publications, data, and maps. An extensive dictionary of renewable energy related terms is also provided. This page has links to: -Archived Data -NREL Data Collection Activities -Solar Spectra -Solar Codes & Algorithms -Solar Models -Solar Calculators -Publications. Keyword: Photovoltaic, cell, PV.

2012-10-15

418

RADIATION SHIELDING DEVICE  

DOEpatents

ABS>A radiation shield that is suitable for the protection of personnel from both gamma rays and nentrons is described. The shield is comprised of a hollow wall and an aggregate consisting of iron and water in approximately equal amounts by volume substantially filling the wall. A means is provided to circulate the water through the wall to cool the shield when in use.

Wigner, E.P.; Young, G.J.

1958-09-23

419

Recombination Radiation from Diamond  

Microsoft Academic Search

The spectrum of the recombination radiation from diamond has been measured over the photon energy range 4.9-5.5 eV at 90, 160, 207, and 320K. At 90K, recombination emission has been detected from ten samples out of a batch of fifteen single crystals, the majority of which were known to be relatively defect free. The persistent and usually dominant spectral features

P. J. Dean; I. H. Jones

1964-01-01

420

Optical radiation and visual health  

SciTech Connect

This book provides a focus on the parameters of ultraviolet light, visible, and infrared radiation s which could cause long-term visual health problems in humans. It reviews early research on radiation effects on the eye, and gives detailed attention to the hazardous effects of optical radiation on the retinal pigment epithelium and the photoreceptors. These data are further analyzed with regard to five potential long-term visual health problems; retinal degeneration, visual aging, disorder of visual development, ocular drug phototoxicity, and cataracts. Finally, epidemiologic principles for studying the relationships between optical radiation and long-term visual health problems are reviewed, concluding with the implications for future research and radiation protection. The contents include: historical perspectives; optical radiation and cataracts; the involvement of the retinal pigment epithelium (RPE); optical radiation damage to the ocular photoreceptors; possible role of optical radiation in retinal degenerations; optical radiation and the aged eye; optical radiation effects on aging and visual perception; optical radiation effects on visual development; and index.

Waxler, M.; Hitchins, V.M.

1986-01-01

421

Quantum radiation of oscillons  

SciTech Connect

Many classical scalar field theories possess remarkable solutions: coherently oscillating, localized clumps, known as oscillons. In many cases, the decay rate of classical small amplitude oscillons is known to be exponentially suppressed and so they are extremely long lived. In this work we compute the decay rate of quantized oscillons. We find it to be a power law in the amplitude and couplings of the theory. Therefore, the quantum decay rate is very different to the classical decay rate and is often dominant. We show that essentially all oscillons eventually decay by producing outgoing radiation. In single field theories the outgoing radiation has typically linear growth, while if the oscillon is coupled to other bosons the outgoing radiation can have exponential growth. The latter is a form of parametric resonance: explosive energy transfer from a localized clump into daughter fields. This may lead to interesting phenomenology in the early universe. Our results are obtained from a perturbative analysis, a nonperturbative Floquet analysis, and numerics.

Hertzberg, Mark P. [Center for Theoretical Physics, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States)

2010-08-15

422

Radiation Protection in Canada  

PubMed Central

The current status of radiation protection in Canada is discussed in the second of a three-part series and particular emphasis is placed on the role of the Radiation Protection Division of the Department of National Health and Welfare. Administrative and operational control procedures have been developed, involving prior approval of health safeguards in the radioisotope user's facilities and techniques, and systematic monitoring and inspection. Where necessary, a medical follow-up of accidents and excessive radiation exposures is carried out. In 1963 more than 1600 radioisotope licences were issued. Filmmonitoring service was provided to about 15,500 isotope and x-ray workers. Semiautomatic handling procedures have been developed to meet the increasing demand for film-monitoring services. Monitoring and inspection services have been provided for x-ray workers, and a committee has been formed to develop administrative procedures for health and safety control in x-ray work. Committees have also been set up to review the health and safety aspects of the operation of nuclear reactors and particle accelerators.

Bird, P. M.

1964-01-01

423

Fundamentals of Atmospheric Radiation  

NASA Astrophysics Data System (ADS)

This textbook fills a gap in the literature for teaching material suitable for students of atmospheric science and courses on atmospheric radiation. It covers the fundamentals of emission, absorption, and scattering of electromagnetic radiation from ultraviolet to infrared and beyond. Much of the book applies to planetary atmosphere. The authors are physicists and teach at the largest meteorology department of the US at Penn State. Craig T. Bohren has taught the atmospheric radiation course there for the past 20 years with no book. Eugene Clothiaux has taken over and added to the course notes. Problems given in the text come from students, colleagues, and correspondents. The design of the figures especially for this book is meant to ease comprehension. Discussions have a graded approach with a thorough treatment of subjects, such as single scattering by particles, at different levels of complexity. The discussion of the multiple scattering theory begins with piles of plates. This simple theory introduces concepts in more advanced theories, i.e. optical thickness, single-scattering albedo, asymmetry parameter. The more complicated theory, the two-stream theory, then takes the reader beyond the pile-of-plates theory. Ideal for advanced undergraduate and graduate students of atmospheric science.

Bohren, Craig F.; Clothiaux, Eugene E.

2006-02-01

424

Method for microbeam radiation therapy  

DOEpatents

A method of performing radiation therapy on a patient, involving exposing a target, usually a tumor, to a therapeutic dose of high energy electromagnetic radiation, preferably X-ray radiation, in the form of at least two non-overlapping microbeams of radiation, each microbeam having a width of less than about 1 millimeter. Target tissue exposed to the microbeams receives a radiation dose during the exposure that exceeds the maximum dose that such tissue can survive. Non-target tissue between the microbeams receives a dose of radiation below the threshold amount of radiation that can be survived by the tissue, and thereby permits the non-target tissue to regenerate. The microbeams may be directed at the target from one direction, or from more than one direction in which case the microbeams overlap within the target tissue enhancing the lethal effect of the irradiation while sparing the surrounding healthy tissue.

Slatkin, Daniel N. (Sound Beach, NY); Dilmanian, F. Avraham (Yaphank, NY); Spanne, Per O. (Shoreham, NY)

1994-01-01

425

Influence of Extraterrestrial Radiation on Radiation Portal Monitors  

SciTech Connect

Cosmic radiation and solar flares can be a major source of background radiation at the Earths surface. This paper examines the relationship between extraterrestrial radiation and the detectable background in radiation portal monitors used for homeland security applications. Background radiation data from 13 radiation portal monitor facilities are examined and compared against external sources of data related to extraterrestrial radiation, including measurements at neutron monitors located at 53 cosmic-ray observatories around the Earth, four polar orbiting satellites, three geostationary satellites, ground-based geomagnetic field data from observatories around the Earth, a solar magnetic index, solar radio flux data, and sunspot activity data. Four-years (January 2003 through December 2006) of data are used in this study, which include the latter part of Solar Cycle 23 as solar activity was on the decline. The analysis shows a significant relationship between some extraterrestrial radiation and the background detected in the radiation portal monitors. A demonstrable decline is shown in the average gamma ray and neutron background at the radiation portal monitors as solar activity declined over the period of the study.

Keller, Paul E.; Kouzes, Richard T.

2009-06-01

426

Non-LTE Radiation Transport in High Radiation Plasmas  

SciTech Connect

A primary goal of numerical radiation transport is obtaining a self-consistent solution for both the radiation field and plasma properties. Obtaining such a solution requires consideration of the coupling between the radiation and the plasma. The different characteristics of this coupling for continuum and line radiation have resulted in two separate sub-disciplines of radiation transport with distinct emphases and computational techniques. LTE radiation transfer focuses on energy transport and exchange through broadband radiation, primarily affecting temperature and ionization balance. Non-LTE line transfer focuses on narrowband radiation and the response of individual level populations, primarily affecting spectral properties. Many high energy density applications, particularly those with high-Z materials, incorporate characteristics of both these regimes. Applications with large radiation fields including strong line components require a non-LTE broadband treatment of energy transport and exchange. We discuss these issues and present a radiation transport treatment which combines features of both types of approaches by explicitly incorporating the dependence of material properties on both temperature and radiation fields. The additional terms generated by the radiation dependence do not change the character of the system of equations and can easily be added to a numerical transport implementation. A numerical example from a Z-pinch application demonstrates that this method improves both the stability and convergence of the calculations. The information needed to characterize the material response to radiation is closely related to that used by the Linear Response Matrix (LRM) approach to near-LTE simulation, and we investigate the use of the LRM for these calculations.

Scott, H A

2005-01-07

427

Utrecht Radiative Transfer Courses  

NASA Astrophysics Data System (ADS)

The Utrecht course ``The Generation and Transport of Radiation'' teaches basic radiative transfer to second-year students. It is a much-expanded version of the first chapter of Rybicki & Lightman's ``Radiative Processes in Astrophysics''. After this course, students understand why intensity is measured per steradian, have an Eddington-Barbier feel for optically thick line formation, and know that scattering upsets LTE. The text is a computer-aided translation by Ruth Peterson of my 1992 Dutch-language course. My aim is to rewrite this course in non-computer English and make it web-available at some time. In the meantime, copies of the Peterson translation are made yearly at Uppsala -- ask them, not me. Eventually it should become a textbook. The Utrecht course ``Radiative Transfer in Stellar Atmospheres'' is a 30-hour course for third-year students. It treats NLTE line formation in plane-parallel stellar atmospheres at a level intermediate between the books by Novotny and Boehm-Vitense, and Mihalas' ``Stellar Atmospheres''. After this course, students appreciate that epsilon is small, that radiation can heat or cool, and that computers have changed the field. This course is web-available since 1995 and is regularly improved -- but remains incomplete. Eventually it should become a textbook. The three Utrecht exercise sets ``Stellar Spectra A: Basic Line Formation'', ``Stellar Spectra B: LTE Line Formation'', and ``Stellar Spectra C: NLTE Line Formation'' are IDL-based computer exercises for first-year, second-year, and third-year students, respectively. They treat spectral classification, Saha-Boltzmann population statistics, the curve of growth, the FAL-C solar atmosphere model, the role of H-minus in the solar continuum, LTE formation of Fraunhofer lines, inversion tactics, the Feautrier method, classical lambda iteration, and ALI computation. The first two sets are web-available since 1998; the third will follow. Acknowledgement. Both courses owe much to previous Utrecht courses taught by the late Kees Zwaan. The third exercise set was developed by Phil Judge, Mandy Hagenaar, and Thijs Krijger. Reverse acknowledgement. If you are a user of this free material you might refer to this summary and so boost my citation standing. Corrections are also welcome.

Rutten, R. J.

2003-01-01

428

Angular radiation pattern of Smith-Purcell radiation  

SciTech Connect

The power radiation pattern of Smith-Purcell radiation is measured at various latitudes and azimuth angles relative to the electron beam. The experimental data are used to evaluate the various models and the physical mechanisms previously suggested to describe Smith-Purcell radiation. Good agreement is observed between the experimental data and the theoretical curves derive from Van den Berg's analysis (J. Opt. Soc. Am. 63, 1588 (1973)). The radiation mechanism proposed by Salisbury (J. Opt. Soc. Am. 60, 1279 (1970)) was analyzed an shown to be too small to account for the measured radiation. The experimantal and Van den Berg's theory predict stronger emission at azimuthal angles off the plane perpendicular to the gratings. This observation leads to conclusions regarding the design of optical cavities for Smith-Purcell free-electron lasers and orotron millimeter-wavelength-radiation tube devices.

Gover, A.; Dvorkis, P.; Elisha, U.

1984-10-01

429

Dose response of various radiation detectors to synchrotron radiation  

Microsoft Academic Search

Accurate dosimetry is particularly difficult for low- to medium-energy x-rays as various interaction processes with different dependences on material properties determine the dose distribution in tissue and radiation detectors. Monoenergetic x-rays from synchrotron radiation offer the unique opportunity to study the dose response variation with photon energy of radiation detectors without the compounding effect of the spectral distribution of x-rays

Tomas Kron; Lisa Duggan; Tony Smith; Anatoly Rosenfeld; Martin Butson; Greg Kaplan; Steve Howlett; Kazuyuki Hyodo

1998-01-01

430

Analysis of Contribution from Edge Radiation to Optical Diffraction Radiation  

SciTech Connect

Beam size measurement with near-field optical diffraction radiation (ODR) has been carried out successfully at CEBAF. The ODR station is installed on the Hall-A beam line after eight bending magnets. The ODR images were affected by an unexpected radiation. Some calculations for analyzing the source of the radiation will be presented. Furthermore, two schemes will be proposed to alleviate the contamination.

C. Liu, P. Evtushenko, A. Freyberger, C. Liu, A.H. Lumpkin

2009-05-01

431

Radiation Safety: Radiation Dosimetry and CT Dose Reduction Techniques  

Microsoft Academic Search

\\u000a The ability of modern multidetector CT scanners with submillimeter resolution, subsecond rotation time, and large volume imaging\\u000a has resulted in widespread utilization of cardiovascular computed tomographic angiography (CCTA) [1]. However, the widespread\\u000a use of CCTA has also raised concerns about the radiation dose to the patients. The National Council on Radiation Protection,\\u000a NCRP Report No. 160, reported that the radiation

Kai H. Lee

432

Miniature radiation dosimeter for in vivo radiation measurements  

NASA Astrophysics Data System (ADS)

The use of ionizing radiation from various sources for the treatment of tumors is widespread. There are no commercial devices for in vivo, real time, dosimetry of patients. The dose to be given a patient is determined from computer modelling and the calibration of the radiation sources. A miniature dosimeter which was mounted in a 1 mm catheter is described. The active device is a radiation sensing field effect transistor (RADFET) which can be used in either an active or passive mode. The RADFET in a catheter is designed to be used during implant radiation therapy of the breast, prostrate, cervix, among other modalities. Its use and operation is described.

Hughes, R. C.; Huffman, D.; Snelling, J. V.; Zipperian, T. E.; Ricco, A. J.; Kelsey, C. A.

433

Virtual Gamma Ray Radiation Sources through Neutron Radiative Capture  

SciTech Connect

The countrate response of a gamma spectrometry system from a neutron radiation source behind a plane of moderating material doped with a nuclide of a large radiative neutron capture cross-section exhibits a countrate response analogous to a gamma radiation source at the same position from the detector. Using a planar, surface area of the neutron moderating material exposed to the neutron radiation produces a larger area under the prompt gamma ray peak in the detector than a smaller area of dimensions relative to the active volume of the gamma detection system.

Scott Wilde, Raymond Keegan

2008-07-01

434

Radiation shielding quality assurance  

NASA Astrophysics Data System (ADS)

For the radiation shielding quality assurance, the validity and reliability of the neutron transport code MCNP, which is now one of the most widely used radiation shielding analysis codes, were checked with lot of benchmark experiments. And also as a practical example, follows were performed in this thesis. One integral neutron transport experiment to measure the effect of neutron streaming in iron and void was performed with Dog-Legged Void Assembly in Knolls Atomic Power Laboratory in 1991. Neutron flux was measured six different places with the methane detectors and a BF-3 detector. The main purpose of the measurements was to provide benchmark against which various neutron transport calculation tools could be compared. Those data were used in verification of Monte Carlo Neutron & Photon Transport Code, MCNP, with the modeling for that. Experimental results and calculation results were compared in both ways, as the total integrated value of neutron fluxes along neutron energy range from 10 KeV to 2 MeV and as the neutron spectrum along with neutron energy range. Both results are well matched with the statistical error +/-20%. MCNP results were also compared with those of TORT, a three dimensional discrete ordinates code which was developed by Oak Ridge National Laboratory. MCNP results are superior to the TORT results at all detector places except one. This means that MCNP is proved as a very powerful tool for the analysis of neutron transport through iron & air and further it could be used as a powerful tool for the radiation shielding analysis. For one application of the analysis of variance (ANOVA) to neutron and gamma transport problems, uncertainties for the calculated values of critical K were evaluated as in the ANOVA on statistical data.

Um, Dallsun

435

Structure in Radiating Shocks  

NASA Astrophysics Data System (ADS)

The basic radiative shock experiment is a shock launched into a gas of high-atomic-number material at high velocities, which fulfills the conditions for radiative losses to collapse the post-shock material to over 20 times the initial gas density. This has been accomplished using the OMEGA Laser Facility by illuminating a Be ablator for 1 ns with a total of 4 kJ, launching the requisite shock, faster than 100 km/sec, into a polyimide shock tube filled with Xe. The experiments have lateral dimensions of 600 ?m and axial dimensions of 2-3 mm, and are diagnosed by x-ray backlighting. Repeatable structure beyond the one-dimensional picture of a shock as a planar discontinuity was discovered in the experimental data. One form this took was that of radial boundary effects near the tube walls, extended approximately seventy microns into the system. The cause of this effect - low density wall material which is heated by radiation transport ahead of the shock, launching a new converging shock ahead of the main shock - is apparently unique to high-energy-density experiments. Another form of structure is the appearance of small-scale perturbations in the post-shock layer, modulating the shock and material interfaces and creating regions of enhanced and diminished aerial density within the layer. The authors have applied an instability theory, a variation of the Vishniac instability of decelerating shocks, to describe the growth of these perturbations. We have also applied Bayesian statistical methods to better understand the uncertainties associated with measuring shocked layer thickness in the presence of tilt. Collaborators: R. P. Drake, H. F. Robey, C. C. Kuranz, C. M. Huntington, M. J. Grosskopf, D. C. Marion.

Doss, Forrest

2010-11-01

436

Primary Radiation Damage Formation  

SciTech Connect

The physical processes that give rise to changes in the microstructure, and the physical and mechanical properties of materials exposed to energetic particles are initiated by essentially elastic collisions between atoms in what has been called an atomic displacement cascade. The formation and evolution of this primary radiation damage mechanism are described to provide an overview of how stable defects are formed by displacement cascades, as well as the nature and morphology of the defects themselves. The impact of the primary variables cascade energy and irradiation temperature are discussed, along with a range of secondary factors that can influence damage formation.

Stoller, Roger E [ORNL

2012-01-01

437

Radiation imaging apparatus  

DOEpatents

A radiation imaging system using a charge multiplier and a position sensitive anode in the form of periodically arranged sets of interconnected anode regions for detecting the position of the centroid of a charge cloud arriving thereat from the charge multiplier. Various forms of improved position sensitive anodes having single plane electrode connections are disclosed. Various analog and digital signal processing systems are disclosed, including systems which use the fast response of microchannel plates, anodes and preamps to perform scintillation pulse height analysis digitally.

Anger, Hal O. (Berkeley, CA); Martin, Donn C. (Berkeley, CA); Lampton, Michael L. (Berkeley, CA)

1983-01-01

438

Radiation imaging apparatus  

DOEpatents

A radiation imaging system using a charge multiplier and a position sensitive anode in the form of periodically arranged sets of interconnected anode regions for detecting the position of the centroid of a charge cloud arriving thereat from the charge multiplier. Various forms of improved position sensitive anodes having single plane electrode connections are disclosed. Various analog and digital signal processing systems are disclosed, including systems which use the fast response of microchannel plates, anodes and preamps to perform scintillation pulse height analysis digitally. 15 figs.

Anger, H.O.; Martin, D.C.; Lampton, M.L.

1983-07-26

439

Management of radiation wounds  

PubMed Central

Radiotherapy forms an integral part in cancer treatment today. It is used alone or in combination with surgery and chemotherapy. Although radiotherapy is useful to effect tumour death, it also exerts a deleterious effect on surrounding normal tissues. These effects are either acute or can manifest months or years after the treatment. The chronic wounds are a result of impaired wound healing. This impairment results in fibrosis, nonhealing ulcers, lymphoedema and radionecrosis amongst others. This article will discuss the pathophysiology in brief, along with the manifestations of radiation-induced injury and the treatment available currently

Iyer, Subramania; Balasubramanian, Deepak

2012-01-01

440

Iron, radiation, and cancer.  

PubMed Central

Increased iron content of cells and tissue may increase the risk of cancer. In particular, high available iron status may increase the risk of a radiation-induced cancer. There are two possible mechanisms for this effect: iron can catalyze the production of oxygen radicals, and it may be a limiting nutrient to the growth and development of a transformed cell in vivo. Given the high available iron content of the western diet and the fact that the world is changing to the western model, it is important to determine if high iron increases the risk of cancer.

Stevens, R G; Kalkwarf, D R

1990-01-01

441

Radiation: Balancing the record  

SciTech Connect

This article reviews the radioactivity experiments performed on humans during the cold war, and examines the ethics of the experiments. The radiation experiments can be broadly classified into three groups: researchers knowingly inflicted potential harm, using methods questionable even by the then-current standards; the investigations involved good work by any standards with appropriate safeguards taken; and a third group which falls between the other two, the experiments provided useful information but had ethical flaws. The article also examines the experiments in the light of changing knowledge and moral standards.

Mann, C.C.

1994-01-28

442

RADIATION SHIELDING COMPOSITION  

DOEpatents

A light weight radiation shielding composition is described whose mechanical and radiological properties can be varied within wide limits. The composition of this shielding material consists of four basic ingredients: powder of either Pb or W, a plastic resin, a resin plasticizer, and a polymerization catalyst to promote an interaction of the plasticizer with the plastic resin. Air may be mixed into the above ingredients in order to control the density of the final composition. For equivalent gamma attenuation, the shielding composition weighs one-third to one-half as much as conventional Pb shielding. (AEC)

Dunegan, H.L.

1963-01-29

443

Occupational radiation exposure: population studies.  

PubMed

Occupational exposure to ionizing radiation in the medical setting differs from the acute exposure received by survivors of atomic bomb blasts. Yet, atomic bomb survivors' disease and mortality outcomes have been the standard data source on the effects of ionizing radiation on humans. Therefore, the prevailing estimated risks of ionizing radiation may not apply to radiologic technologists and other medical radiation workers. Carefully designed epidemiological trials provide evidence that helps determine the strength of association between exposure and onset of disease in selected populations. This article reviews radiation effects, explains some basic design concepts of epidemiologic trials and surveys the epidemiology literature related to radiation exposure to humans, with special attention to radiology staff. PMID:15732889

Schleipman, A Robert

444

RADIATIVE RAYLEIGH-TAYLOR INSTABILITIES  

SciTech Connect

We perform analytic linear stability analyses of an interface separating two stratified media threaded by a radiation flux, a configuration relevant in several astrophysical contexts. We develop a general framework for analyzing such systems and obtain exact stability conditions in several limiting cases. In the optically thin, isothermal regime, where the discontinuity is chemical in nature (e.g., at the boundary of a radiation pressure-driven H II region), radiation acts as part of an effective gravitational field, and instability arises if the effective gravity per unit volume toward the interface overcomes that away from it. In the optically thick 'adiabatic' regime where the total (gas plus radiation) specific entropy of a Lagrangian fluid element is conserved, for example at the edge of radiation pressure-driven bubble around a young massive star, we show that radiation acts like a modified equation of state and derive a generalized version of the classical Rayleigh-Taylor stability condition.

Jacquet, Emmanuel [Laboratoire de Mineralogie et Cosmochimie de Museum (LMCM), CNRS and Museum National d'Histoire Naturelle, UMR 7202, 57 rue Cuvier, 75005 Paris (France); Krumholz, Mark R., E-mail: ejacquet@mnhn.fr, E-mail: krumholz@ucolick.org [Department of Astronomy, University of California, Santa Cruz, CA 95064 (United States)

2011-04-01

445

Future perspectives of radiation chemistry  

NASA Astrophysics Data System (ADS)

Future perspectives of radiation chemistry are discussed by the analysis of the related information in detail as obtained from our recent surveys of publications and scientific meetings in radiation chemistry and its neighboring research fields, giving some examples, and are summarized as follows. (1) Traditionally important core-parts of radiation chemistry should be activated more. The corresponding research programs are listed in detail. (2) Research fields of physics, chemistry, biology, medicine, and technology in radiation research should interact more among them with each other. (3) Basic research of radiation chemistry should interact more with its applied research. (4) Interface research fields with radiation chemistry should be produced more with mutually common viewpoints and research interests between the two. Interfaces are not only applied research but also basic one.

Hatano, Yoshihiko

2009-12-01

446

Radiation-induced thyroid disease  

SciTech Connect

Ionizing radiation has been demonstrated to result in a number of changes in the human thyroid gland. At lower radiation dose levels (between 10 and 1500 rads), benign and malignant neoplasms appear to be the dominant effect, whereas at higher dose levels functional changes and thyroiditis become more prevalent. In all instances, the likelihood of the effect is related to the amount and type of radiation exposure, time since exposure, and host factors such as age, sex, and heredity. The author's current approach to the evaluation of patients with past external radiation therapy to the thyroid is discussed. The use of prophylactic thyroxine (T4) therapy is controversial. While T4 therapy may not be useful in preventing carcinogenesis when instituted many years after radiation exposure, theoretically T4 may block TSH secretion and stimulation of damaged cells to undergo malignant transformation when instituted soon after radiation exposure.

Maxon, H.R.

1985-09-01

447

Nonionizing Radiation Around Linear Accelerators  

Microsoft Academic Search

The World Health Organization, the International Radiation Protection Association (IRPA), and the American Conference of Governmental Industrial Hygienists have recommended using time-weighted and time-dependent standards for nonionizing radiation exposure assessment. Such hygienic norms have been developed on the basis of the electromagnetic energy evaluation. Two Varian linear accelerators, Clinac 1800 and Clinac 6X, were examined for different nonionizing radiation hazards.

Michel S. Israel; Yona Mahler; Dan Blau; Ezra Levinger

1995-01-01

448

Deterministic methods in radiation transport  

SciTech Connect

The Seminar on Deterministic Methods in Radiation Transport was held February 4--5, 1992, in Oak Ridge, Tennessee. Eleven presentations were made and the full papers are published in this report, along with three that were submitted but not given orally. These papers represent a good overview of the state of the art in the deterministic solution of radiation transport problems for a variety of applications of current interest to the Radiation Shielding Information Center user community.

Rice, A.F.; Roussin, R.W. (eds.)

1992-06-01

449

The Nature of Electromagnetic Radiation  

NSDL National Science Digital Library

This web site is a reference page on electromagnetic radiation. It discusses the spectrum of light and both the wave and quantum nature of radiation. Also included are descriptions of the physics and applications of the different frequency bands, from gamma rays through radio waves, plus links to interactive Java simulations on the topic. See Related Materials on this page for a simpler student tutorial by the same authors on the topic of electromagnetic radiation.

Davidson, Michael; Abramowitz, Mortimer; Fellers, Thomas J.

2008-08-21

450

Radiation Oncology Advances: An Introduction  

Microsoft Academic Search

Radiation therapy remains a mainstay of cancer treatment: it is estimated that around half of all cancer patients in Europe,\\u000a in the US probably close to two-thirds, receive radiation therapy as part of their initial therapy, for salvage or for palliation.\\u000a There are good reasons to expect the role of radiation therapy in the management of cancer to expand in

Sren M. Bentzen; Paul M. Harari; Wolfgang A. Tom; Minesh P. Mehta

451

Space Radiation and Bone Loss.  

PubMed

Exposure to ionizing radiation may negatively impact skeletal integrity during extended spaceflight missions to the moon, Mars, or near-Earth asteroids. However, our understanding of the effects of radiation on bone is limited when compared to the effects of weightlessness. In addition to microgravity, astronauts will be exposed to space radiation from solar and cosmic sources. Historically, radiation exposure has been shown to damage both osteoblast precursors and local vasculature within the irradiated volume. The resulting suppression of bone formation and a general state of low bone-turnover is thought to be the primary contributor to bone loss and eventual fracture. Recent investigations using mouse models have identified a rapid, but transient, increase in osteoclast activity immediately after irradiation with both spaceflight and clinically-relevant radiation qualities and doses. Together with a chronic suppression of bone formation after radiation exposure, this acute skeletal damage may contribute to long-term deterioration of bone quality, potentially increasing fracture risk. Direct evidence for the damaging effects of radiation on human bone are primarily demonstrated by the increased incidence of fractures at sites that absorb high doses of radiation during cancer therapy: exposures are considerably higher than what could be expected during spaceflight. However, both the rapidity of bone damage and the chronic nature of the changes appear similar between exposure scenarios. This review will outline our current knowledge of space and clinical exploration exposure to ionizing radiation on skeletal health. PMID:22826632

Willey, Jeffrey S; Lloyd, Shane A J; Nelson, Gregory A; Bateman, Ted A

2011-01-01

452

Radiative Transfer: Methods and Applications  

NASA Astrophysics Data System (ADS)

Solar and terrestrial radiation is the driver of atmospheric dynamics and chemistry and can be exploited by remote sensing algorithms to determine atmospheric composition. For this purpose, accurate radiative transfer models are needed. Here, a modern radiative transfer tool developed over many years at the Institute of Atmospheric Physics is explained. As an application, the remote sensing of cloud microphysics using the angular distribution of reflected solar radiance in the rainbow and backscatter glory is shown, with special emphasis on the polarization of radiation.

Mayer, Bernhard; Emde, Claudia; Buras, Robert; Kylling, Arve

453

Laser-driven undulator radiation  

SciTech Connect

An electromagnetic wake of infra-red radiation can be generated by an intense laser pulse, propagating through an underdense plasma in the presence of a magnetostatic undulator. As opposed to undulator radiation from a charged bunch propagating in a periodic magnetic field, here radiation comes from almost stationary plasma electrons, ponderomotively pushed by the laser pulse. Such laser-driven undulator radiation can be produced by either a single ultra-short pulse, or by two frequency-detuned long pulses. In the latter case the difference frequency is efficiently produced by quasi phase-matched optical heterodyning.

Shvets, G.; Fisch, N. J.; Pukhov, A. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Max Plank Institute for Quantum Optics, Garching-bei-Munchen (Germany)

1999-07-12

454

Laser-driven undulator radiation  

SciTech Connect

An electromagnetic wake of infra-red radiation can be generated by an intense laser pulse, propagating through an underdense plasma in the presence of a magnetostatic undulator. As opposed to undulator radiation from a charged bunch propagating in a periodic magnetic field, here radiation comes from almost stationary plasma electrons, ponderomotively pushed by the laser pulse. Such laser-driven undulator radiation can be produced by either a single ultra-short pulse, or by two frequency-detuned long pulses. In the latter case the difference frequency is efficiently produced by quasi phase-matched optical heterodyning. {copyright} {ital 1999 American Institute of Physics.}

Shvets, G.; Fisch, N.J. [Princeton Plasma Physics Laboratory, Princeton University, Princeton, New Jersey 08543 (United States); Pukhov, A. [Max Plank Institute for Quantum Optics, Garching-bei-Munchen (Germany)

1999-07-01

455

Development of radiation detection materials  

NASA Astrophysics Data System (ADS)

Electric current output or scintillation light from solid-state inorganic materials under ionizing radiation is very useful for nuclear and radiation detection. Direct electric current measurements in semiconductors or ionic crystals provide high resolution spectroscopy and imaging capability even though there are scalability and cost issues. In contrast, inorganic scintillation materials utilizing photons generated by incident radiation have been developed for many decades and provide better scalability and lower cost. Ceramic materials offer compelling advantages including large size, mechanical strength, and homogeneity. In this work, we review current status of advanced radiation detection materials and introduce our efforts in the development of ceramic scintillator materials, mainly for gamma ray detection.

Lee, Chae-Deok; Hartnett, Thomas; Tustison, Randy

2012-05-01

456

Lunar radiators with specular reflectors  

NASA Astrophysics Data System (ADS)

A unique radiator, suitable for use in relatively hot thermal environments such as the moon, has been devised and analyzed. The radiator uses a parabolic specular reflector to deflect the solar rays and to shield the radiator from the hot lunar soil. It can provide sink temperatures on the order of 147 K and effective emittances approximately equal to the emittance of the surface of the radiator. Similar performance can be obtained on sun-oriented spacecraft that have a limited view of space.

Costello, Frederick A.; Swanson, T. D.

1990-01-01

457

Sources of ionizing radiation exposure  

SciTech Connect

Until recently, the radiations to which people were exposed were limited to those that exist naturally. But beginning about a century ago a number of advances in science and engineering altered our radiation environment. The use of X rays, radioactive substances, artificial illumination, and radio communication; the high voltage transmission of electric energy; and even the introduction of high-flying aircraft have all affected the kinds and amounts of radiation to which people are exposed. This article will discuss only the ionizing radiations, which are those produced by X-ray machines and radionuclides. 22 references

Eisenbud, M.

1984-12-01

458

Radiation Belts and Trapped Particles  

NSDL National Science Digital Library

This tutorial introduces students to Earth's radiation belts, also known as the Van Allen Belts after their discoverer. Topics include the structure of the radiation belts and the currents of particles trapped in Earth's magnetic fields, their properties, and where they come from. There is also a set of classroom activities for exploring radiation belts and solar storms and a set of illustrations and movies of the belts. Other materials include news items related to the radiation belts, recordings of 'space sounds' related to the influence of lightning on Earth's magnetic field, and a frequently-asked-questions feature.

459

Inverse problem for Bremsstrahlung radiation  

SciTech Connect

For certain predominantly one-dimensional distribution functions, an analytic inversion has been found which yields the velocity distribution of superthermal electrons given their Bremsstrahlung radiation. 5 refs.

Voss, K.E.; Fisch, N.J.

1991-10-01

460

Radiation safety for radiologic technologists.  

PubMed

Radiologic technologists and ancillary staff who work with or near ionizing radiation face possible short- and long-term effects of occupational radiation exposure. Further, radiologic technologists must minimize unnecessary exposure that risks the patient's safety, while achieving the best possible image or outcome. This article reviews occupational dose limits, dose calculation, devices used to measure exposure, and safety best practices that can help technologists keep radiation exposure "as low as reasonably achievable" for them and their patients. The article also discusses the appropriate use of mounted and mobile equipment, personal protective equipment, and safety features on imaging equipment to minimize unnecessary radiation exposure. PMID:22596024

Bradley, Lee A

461

Scintillator Waveguide For Sensing Radiation  

DOEpatents

The present invention is an apparatus for detecting ionizing radiation, having: a waveguide having a first end and a second end, the waveguide formed of a scintillator material wherein the therapeutic ionizing radiation isotropically generates scintillation light signals within the waveguide. This apparatus provides a measure of radiation dose. The apparatus may be modified to permit making a measure of location of radiation dose. Specifically, the scintillation material is segmented into a plurality of segments; and a connecting cable for each of the plurality of segments is used for conducting scintillation signals to a scintillation detector.

Bliss, Mary (West Richland, WA); Craig, Richard A. (West Richland, WA); Reeder; Paul L. (Richland, WA)

2003-04-22

462

Ionizing radiation promotes protozoan reproduction  

SciTech Connect

This experiment was performed to determine whether ionizing radiation is essential for maximum growth rate in a ciliated protozoan. When extraneous ionizing radiation was reduced to 0.15 mrad/day, the reproduction rate of Tetrahymena pyriformis was significantly less (P less than 0.01) than it was at near ambient levels, 0.5 or 1.8 mrad/day. Significantly higher growth rates (P less than 0.01) were obtained when chronic radiation was increased. The data suggest that ionizing radiation is essential for optimum reproduction rate in this organism.

Luckey, T.D.

1986-11-01

463

Space radiation studies  

NASA Astrophysics Data System (ADS)

Two Active Radiation Dosimeters (ARD's) flown on Spacelab 1, performed without fault and were returned to Space Science Laboratory, MSFC for recalibration. During the flight, performance was monitored at the Huntsville Operations Center (HOSC). Despite some problems with the Shuttle data system handling the verification flight instrumentation (VFI), it was established that the ARD's were operating normally. Postflight calibrations of both units determined that sensitivities were essentially unchanged from preflight values. Flight tapes were received for approx. 60 percent of the flight and it appears that this is the total available. The data was analyzed in collaboration with Space Science Laboratory, MSFC. Also, the Nuclear Radiation Monitor (NRM) was assembled and tested at MSFC. Support was rendered in the areas of materials control and parts were supplied for the supplementary heaters, dome gas-venting device and photomultiplier tube housing. Performance characteristics of some flight-space photomultipliers were measured. The NRM was flown on a balloon-borne test flight and subsequently performed without fault on Spacelab-2. This data was analyzed and published.

464

Solar Radiation Storm  

NSDL National Science Digital Library

This past week has offered much excitement for space weather scientists and enthusiasts, alike. On Friday July 14, a major flare shot off the surface of the sun, pummeling Earth with a massive solar-radiation storm that interfered with satellite and radio communications and delayed a Russian space launch. The flare was one of the most powerful of the current eleven-year solar cycle (and the biggest solar radiation event since 1989) and was followed by a coronal mass ejection -- "a blast of billions of tons of electrically charged atomic particles and magnetic energy hurled in the Earth's direction at 3 million miles an hour" (1). When a very powerful coronal mass ejection hits the Earth's magnetosphere, a shock wave can compress the magnetosphere and unleash a geomagnetic storm -- causing interference with electric power transmission and triggering beautiful aurorae. Friday's flare was one of three storms last week, and the biggest since a small solar storm made the news in June (see the June 9, 2000 Scout Report for additional resources). Although this weekend's storms have diminished, more activity is anticipated as the sunspot group that is producing flares (region 9077) will continue to face the earth for another week.

Payne, Laura X.

465

Management of radiation ulcers  

SciTech Connect

Despite more efficient and safer technics of radiation therapy, the problem of radiation-induced injury to the skin and soft tissue persists. The problem of adequate coverage of these painful, ischemic, and fibrotic ulcers remains challenging. Split-thickness skin grafts are seldom sufficient coverage, as the graft almost always has areas that do not take. Although these areas may eventually heal by epithelialization, the result is never ideal. Most often flap coverage is required, but elevation of local flaps is jeopardized because the tissue surrounding the ulcer crater frequently has been sufficiently compromised to cause loss of at least part of the flap. In the past, this necessitated use of pedicled flaps, tubed and transposed from a distance. With the development of axial-pattern musculocutaneous and muscle flaps, as well as microvascular free flaps, the difficulty in dealing with these ulcers has been decreased. Surgeons can now recommend earlier use of adequate debridement, many times of the entire irradiated area, and immediate coverage with a well vascularized axial-pattern musculocutaneous flap or revascularized free flap.

Shack, R.B.

1982-12-01

466

Imaging with terahertz radiation  

NASA Astrophysics Data System (ADS)

Within the last several years, the field of terahertz science and technology has changed dramatically. Many new advances in the technology for generation, manipulation, and detection of terahertz radiation have revolutionized the field. Much of this interest has been inspired by the promise of valuable new applications for terahertz imaging and sensing. Among a long list of proposed uses, one finds compelling needs such as security screening and quality control, as well as whimsical notions such as counting the almonds in a bar of chocolate. This list has grown in parallel with the development of new technologies and new paradigms for imaging and sensing. Many of these proposed applications exploit the unique capabilities of terahertz radiation to penetrate common packaging materials and provide spectroscopic information about the materials within. Several of the techniques used for terahertz imaging have been borrowed from other, more well established fields such as x-ray computed tomography and synthetic aperture radar. Others have been developed exclusively for the terahertz field, and have no analogies in other portions of the spectrum. This review provides a comprehensive description of the various techniques which have been employed for terahertz image formation, as well as discussing numerous examples which illustrate the many exciting potential uses for these emerging technologies.

Chan, Wai Lam; Deibel, Jason; Mittleman, Daniel M.

2007-08-01

467

Radiative divertor modeling studies  

SciTech Connect

A two-dimensional fluid code called UEDGE is used to simulate the edge plasma in tokamak divertors and to evaluate methods for reducing the heat load on divertor plates by radiating some of the power before it reaches the plates. UEDGE is a fully-implicit code being developed jointly by us, D. A. Knoll and R. B. Campbell. For these studies, UEDGE uses a banded matrix solver and a fixed-fraction impurity model. Work is presently underway with Knoll and Campbell to include a memory-efficient iterative solver and a model of impurity transport. Simulations of the proposed TPX device show that a few percent nitrogen concentration in the scrape-off layer can radiate up to 80% of the divertor power, thus reducing the peak heat flux and electron temperature at the divertor plate to acceptable values. A comparison of the neutral gas distribution from UEDGE with results from the DEGAS Monte Carlo neutrals code confirms the validity of our fluid neutrals model.

Rensink, M.E.; Allen, S.L.; Hill, D.N.; Kaiser, T.B.; Rognlien, T.D.

1993-05-05

468

Using radiation risk for assessment of space radiation hazard  

NASA Astrophysics Data System (ADS)

Radiation hazard caused by exposure during a spaceflight is characterized by radiobiological consequences at all levels of organism. These consequences have a stochastic nature. Even deterministic effects are basically random quantity having all attributes of such mathematical values. The radiation risk is defined in this case as an additional probability of health damage or as a death probability in extreme case. For the manned spaceflight additional peculiarity of a human's exposure is added. A natural space radiation environment has a stochastic character because solar particle events and crew of a spacecraft can be exposed to dose from background level up to lethal one. The report presents a procedure of radiation risk assessment for quantitative expression of radiation hazard level during a flight and using this value for developing protection recommendations. It is emphasized that the risk value is connected specifically with the time interval of possible hazard's existent. The form of risk representation must be chosen depending on a time scale of radiobiological processes induced by the exposure (expressing in fact the radiation hazard model). Surviving function specified for the crewmember mortality rate changed by the professional exposure must be used for risk calculation. Solar particle events determine a stochastic character of radiation environment in space that must be taken into account for a risk assessment. The reliability of radiation risk assessment can be used for this goal.

Petrov, V. M.

2011-05-01

469

Radiation defect clustering in graphite studied by synchrotron radiation scattering  

Microsoft Academic Search

The formation of radiation defect clusters as interstitial dislocation loops in pyrographite irradiated by 20-MeV carbon ions in a cyclotron has been studied by means of synchrotron radiation scattering. The experimental data are interpreted in terms of the Krivoglaz model and the model of deformation domain formation by dislocation loops. Parameters of the pyrographite crystal lattice in the deformed state

A. I. Ryazanov; M. V. Koval'Chuk; E. Kh. Mukhamedzhanov; V. N. Peregudov; S. T. Latushkin; A. N. Morkovin; M. M. Borisov; V. N. Unezhev

2008-01-01

470

Hypopharyngeal carcinoma after radiation for tuberculosis: radiation-induced carcinoma.  

PubMed

Radiation may cause radiation-induced cancers after a long latency period. In a group of 111 patients surgically treated for hypopharyngeal carcinoma, patients previously treated with radiotherapy for tuberculosis in the neck were compared to patients without previous radiotherapy. Seven patients (7.4%) underwent radiotherapy (median age 15 years) and developed a hypopharyngeal carcinoma (median age 70 years, median latency period 54.4 year). Considering this long latency period and the localisation in the previous radiation field these tumours can be classified as potentially radiation-induced carcinomas. Patients with potentially radiation-induced carcinomas were significantly older when the hypopharyngeal carcinoma was diagnosed (p=0.048), were more frequently females (p=0.05) and had a worse 5-year regional control rate (p=0.048). When radiotherapy is considered in young patients the risk of induction of tumours has to be kept in mind. PMID:20656544

van der Putten, Lisa; de Bree, Remco; Kuik, Dirk J; Rietveld, Derek H F; Langendijk, Johannes A; Leemans, C Ren

2010-07-24

471

[Radiation therapy in thyroid cancer].  

PubMed

Anaplastic thyroid cancers represent 1-2% of all thyroid tumours and are of very poor prognosis even with multimodality treatment including external beam radiation therapy. Conversely, differentiated thyroid carcinomas (at least 80% of thyroid cancers) hamper good prognosis with surgery with or without radioiodine and there is hardly any room for external beam radiation therapy. Insular and medullar carcinomas have intermediary prognosis and are rarely irradiated. We aimed to update recommendations for external beam irradiation in these different clinical situations and put in light the benefits of new irradiations techniques. A search of the French and English literature was performed using the following keywords: thyroid carcinoma, anaplastic, chemoradiation, radiation therapy, surgery, histology and prognostic. Non-mutilating surgery (often limited to debulking) followed by systematic external beam radiation therapy is the standard of care in anaplastic thyroid cancers (hyperfractionated-accelerated radiation therapy with low-dose weekly doxorubicin with or without cisplatin if possible). Given anaplastic thyroid cancers' median survival of 10 months or less, neoadjuvant and adjuvant chemotherapy may also be discussed. Ten-year survival rates for patients with papillary, follicular and Hrthle-cell carcinomas are 93%, 85%, and 76%, respectively. Massive primary incompletely resected iodine-negative disease indicates external beam radiation therapy. Older age (45 or 60-year-old), poor-prognosis histological variants (including tall cell cancers) and insular cancers are increasingly reported as criteria for external beam radiation therapy. Massive extracapsular incompletely resected nodal medullary disease suggests external beam radiation therapy. Radiation therapy morbidity has been an important limitation. However, intensity modulated radiation therapy (IMRT) offers clear dosimetric advantages on tumour coverage and organ sparing, reducing late toxicities to less than 5%. The role of radiation therapy is evolving for anaplastic thyroid cancers using multimodal strategies and new chemotherapy molecules, and for differentiated cancers using minor criteria, such as histological variants, with IMRT becoming a standard of care. PMID:23763764

Sun, X S; Guevara, N; Fakhry, N; Sun, S-R; Marcy, P-Y; Santini, J; Bosset, J-F; Thariat, J

2013-02-08

472

Coherent radiation experiments at Tohoku University  

SciTech Connect

Experimental activities at Tohoku University using a short bunch from the electron linac are presented. Studies on coherent synchrotron radiation, coherent transition radiation, coherent Cherenkov radiation, Smith-Purcell radiation and diffraction radiation are being carried out. {copyright} {ital 1996 American Institute of Physics.}

Nakazato, T. [Laboratory of Nuclear Science, Tohoku University, 1-2-1 Mikamine, Taihaku-ku Sendai, 982 (JAPAN)

1996-04-01

473

Stationary radiation of objects with scattering media  

Microsoft Academic Search

The radiation observed inside or outside a stationary radiator with a scattering medium is a sum of components, each being determined by, first, the primary radiation from some part of the radiator and, second, the probability of this radiation reaching the region where it is observed. In this review, general and rather simple relations between these components are discussed. These

Inna A Vasileva

2001-01-01

474

Fan casing noise radiation  

NASA Astrophysics Data System (ADS)

The extent of the fan-casing noise radiation of a centrifugal fan, relative to the aeroacoustic sources associated with the inlet box of the fan was investigated using a boundary element program for computing the acoustic pressures on the surfaces of the fan casing in terms of its experimentally measured surface vibration. As the starting point for the study, data were obtained from the experiments of Neise and Koopmann (1984) on the sound pressure measurements near and away from the inlet box of the fan and on vibration measurements over the casing of the fan. A comparison of the relative contributions of the fan casing and the inlet box to the sound level measured at 80 cm above the inlet box showed that, at 300 Hz, the noise was dominated by the aeroacoustic sources at the inlet box. However, at 150 Hz, the contributions from the fan casing and the inlet box were nearly the same.

Koopmann, G. H.; Cunefare, K. A.; Neise, W.

1991-01-01

475

Clinical radiation nephropathy  

SciTech Connect

An analysis of the normal tissue effects of irradiation of the kidney is presented. Various clinical syndromes resulting from treatment are described as well as the potential cellular basis for these findings. Effects of concurrent and/or sequential treatment with irradiation and various chemotherapeutic agents are discussed and the impact of these agents on toxicity presented. Adverse consequences of renal treatment in the child is described and possible radiation effects on so-called compensatory hypertrophy following nephrectomy presented. Renal consequences described to date of bone marrow transplantation programs utilizing irradiation are also presented. The necessity of a dose-volume histogram analysis approach to analyzing renal toxic effects in patients followed for long (>10 year) periods is essential in developing accurate guidelines of renal tolerance. 53 refs., 6 figs., 5 tabs.

Cassady, J.R. [Univ. of Arizona Health Sciences Center, Tucson, AZ (United States)

1995-03-30

476

Linked Gravitational Radiation  

NASA Astrophysics Data System (ADS)

The electromagnetic knot is a topologically nontrivial solution to the vacuum Maxwell equations with the property that any two field lines belonging to either the electric, magnetic, or Poynting vector fields are closed and linked exactly once [1]. The relationship between the vacuum Maxwell and linearized Einstein equations, as expressed in the form of the spin-N massless field equations, suggests that gravitational radiation possesses analogous topologically nontrivial field configurations. Using twistor methods we find the analogous spin-2 solutions of Petrov types N, D, and III. Aided by the concept of tendex and vortex lines as recently developed for the physical interpretation of solutions in general relativity [2], we investigate the physical properties of these knotted gravitational fields by characterizing the topology of their associated tendex and vortex lines.[4pt] [1] Ranada, A. F. and Trueba, J. L., Mod. Nonlinear Opt. III, 119, 197 (2002).[2] Nichols, D. A., et al., Phys. Rev. D, 84 (2011).

Thompson, Amy; Swearngin, Joseph; Wickes, Alexander; Willem Dalhuisen, Jan; Bouwmeester, Dirk

2013-04-01

477

Has ionizing radiation biopositive effects  

Microsoft Academic Search

The question of whether ionizing radiation has a positive effect on ; living matter is critically examined. In doing this the author closely ; investigates the application of radioactivity for curing purposes, as well as the ; use of ionizing radiation for therapeutical purposes, as long as it's not being ; used for the therapy of cancer. Reports on the

Broda

1973-01-01

478

RADIATION DETECTION AT BATTALION LEVEL  

Microsoft Academic Search

The purpose and scope of radiation detection is outlined, illustrating ; how and by whom such detection should be carried out at battalion level. judging ; by the results of radiation detection, the battalion commander decides how his ; troops will cross through the contamirated area and works out plans for ; eliminating the after-effects of radioactive contamination. When an

Manets

1960-01-01

479

BIOLOGICAL EFFECTS OF RADIOFREQUENCY RADIATION  

EPA Science Inventory

The document presents a critical review of the available literature on the biological effects of radiofrequency (RF) radiation. The objective was to summarize and evaluate the existing database for use in developing RF-radiation exposure guidance for the general public. The frequ...

480

An introduction to radiation chemistry  

Microsoft Academic Search

This book covers developments in the field of radiation chemistry. This text provides a point of entry into the field. The authors promote understanding of the fundamental principles underlying the action of radiation on matter. Both the methodology and the industrial applications are stated.

J. W. T. Spinks; R. J. Woods

1990-01-01

481

Radiation-induced optic neuropathy  

Microsoft Academic Search

Radiation-induced optic neuropathy (RION) is a devastating late complication of radiotherapy to the anterior visual pathway resulting in acute, profound, irreversible visual loss. It is thought to be a result of radiation necrosis of the anterior visual pathway. Visual loss may be unilateral or bilateral; simultaneous or sequential. RION occurs commonly between 10-20 months, with an average of 18 months

Helen V. Danesh-Meyer

2008-01-01

482

Radiation carcinogenesis: radioprotectors and photosensitizers  

SciTech Connect

This paper outlines 1) some of the salient features of radiation carcinogenesis that are pertinent to the questions of how the carcinogenic effects might be influenced, 2) the effects of radioprotectors on ionizing radiation-induced cancer, and 3) the effect of photosensitizers on UVR-induced skin cancer.

Fry, R.J.M.

1982-01-01

483

Public Health Aspects of Radiation.  

National Technical Information Service (NTIS)

The sources and levels of natural and manmade radiation are discussed in this report, and the resulting risks of radiation-induced cancer and hereditary diseases are estimated. The medical uses of X-rays currently increase the average population exposure ...

H. B. Newcombe

1978-01-01

484

Protective prostheses during radiation therapy  

SciTech Connect

Current applications and complications in the use of radiotherapy for the treatment of oral malignancy are reviewed. Prostheses are used for decreasing radiation to vital structures not involved with the lesion but located in the field of radiation. With a program of oral hygiene and proper dental care, protective prostheses can help decrease greatly the morbidity seen with existing radiotherapy regimens.

Poole, T.S.; Flaxman, N.A.

1986-04-01

485

Radiation response of cell organelles  

Microsoft Academic Search

The cellular responses to various form of radiation, including ionizing- and UV-irradiation or exposure to electromagnetic fields is manifested as irreversible and reversible structural and functional changes to cells and cell organelles. Moreover, beside the morphological signs related to cell death, there are several reversible alterations in the structure of different cell organelles. The radiation-induced changes in the supramolecular organization

Z. Somosy

2000-01-01

486

Radiation Protection in Interventional Radiology (*)  

Microsoft Academic Search

Interventional procedures are used by a significant number of medical specialities. Radiation protection (RP) for patients and staff is one of the main issues in Interventional Radiology (IR). UNSCEAR, ICRP and IAEA have devoted significant time over the last years to improve radiation safety in IR. Several combined factors: prolonged localized fluoroscopy, multiple radiographic exposures, and repeated procedures can cause

Eliseo Vano

487

Quantum effects in channeling radiation  

Microsoft Academic Search

The quantum effects on the total radiation intensity in channeling have been considered. It is shown that the problem can be considered in the frame of the magnetic bremsstrahlung limit. In the region where quantum effects are weak, the general formulae have been obtained for quantum corrections to the total intensity of the channeling radiation. While in diamond and silicon

V. N. Baier; V. M. Katkov; V. M. Strakhovenko

1992-01-01

488

Radiation Tolerance of Complex Oxides  

Microsoft Academic Search

The radiation performance of a variety of complex oxides is predicted on the basis of a material's propensity to accommodate lattice point defects. The calculations indicate that a particular class of oxides possessing the fluorite crystal structure should accept radiation-induced defects into their lattices far more readily than a structurally similar class of oxides based on the pyrochlore crystal structure.

K. E. Sickafus; L. Minervini; R. W. Grimes; J. A. Valdez; M. Ishimaru; F. Li; K. J. McClellan; T. Hartmann

2000-01-01

489

Design experience: CRBRP radiation shielding  

Microsoft Academic Search

The Clinch River Breeder Reactor Plant (CRBRP) is being designed as a fast breeder demonstration project in the U.S. Liquid Metal Fast Breeder Reactor (LMFBR) program. Radiation shielding design of the facility consists of a comprehensive design approach to assure compliance with design and government regulatory requirements. Studies conducted during the CRBRP design process involved the aspects of radiation shielding

R. K. Disney; T. C. Chan; F. G. Gallo; L. R. Hedgecock; C. A. McGinnis; G. N. Wrights

1978-01-01

490

Radiative Regime over Arctic Tundra.  

National Technical Information Service (NTIS)

Incoming short wave, total incoming, and net total radiation were measured continuously near Point Barrow, Alaska (71 degrees N), in 1964 using Kipp and Zonen solarimeters and C.S.I.R.O. radiometers. The incoming short wave radiation reached a maximum mon...

B. J. Lieske L. A. Stroschein

1968-01-01

491

Models of diffuse solar radiation  

Microsoft Academic Search

For some locations both global and diffuse solar radiation are measured. However, for many locations, only global is measured, or inferred from satellite data. For modelling solar energy applications, the amount of radiation on a tilted surface is needed. Since only the direct component on a tilted surface can be calculated from trigonometry, we need to have diffuse on the

John Boland; Barbara Ridley; Bruce Brown

2008-01-01

492

Solar radiation on inclined surfaces  

Microsoft Academic Search

Measured solar radiation data for one location in Lesotho is used to test the applicability of two theoretical models for computing total solar radiation on inclined surfaces. The models selected for discussion are the isotropic model suggested by Liu and Jordan and the anisotropic model by Hay. The models are compared and tested for their applicability to locations in Lesotho

K Gopinathan

1990-01-01

493

The cancer epidemiology of radiation  

Microsoft Academic Search

Ionizing radiation has been the subject of intense epidemiological investigation. Studies have demonstrated that exposure to moderate-to-high levels can cause most forms of cancer, leukaemia and cancers of the breast, lung and thyroid being particularly sensitive to induction by radiation, especially at young ages at exposure. Predominant among these studies is the Life Span Study of the cohort of survivors

Richard Wakeford

2004-01-01

494

Saturian kilometric radiation: Source locations  

Microsoft Academic Search

Using Voyager 1 and 2 Planetary Radio Astronomy data and reasonable assumptions about radiation beam geometry, we deduce the source locations of both polarization components of the Saturn kilometer-wavelength radiation. The resulting radio source footprints are at high latitudes north and south, and near the noon meridian. These footprints are compared with the surface locations of Saturn's UV aurorae, polar

M. L. Kaiser; M. D. Desch

1982-01-01

495

An introduction to solar radiation  

Microsoft Academic Search

This book was written for energy analysts, designers of thermal devices, photovoltaic engineers, architects, agronomists, and hydrologists who must calculate an amount of solar radiation incident on a surface. Includes reading lists, diagrams, a subject index and tables with useful data. Contents, abridged: Sun-earth astronomical relationship. The solar constant and its spectral distribution. Extraterrestrial solar irradiation. Solar spectral radiation under

M. Iqbal

1983-01-01

496

Previously Undetected Radiation Belt Revealed  

NASA Video Gallery

Since their discovery over 50 years ago, the Earths Van Allen radiation belts have been considered to consist of two distinct zones of trapped, highly energetic charged particles. Observations from NASAs Van Allen Probes reveal an isolated third ring in the outer radiation belt.

gsfcvideo

2013-02-27

497

The Radiation Belt Storm Probes  

NASA Video Gallery

The Radiation Belt Storm Probe mission (RBSP) will explore the Van Allen Radiation Belts in the Earth's magnetosphere. The charge particles in these regions can be hazardous to both spacecraft and astronauts. The mission will explore space weather -- changes in Earth's space environment caused by the sun -- which can affect our technology.

gsfcvideo

2012-08-09

498

RADIATION INJURIES BY NUCLEAR WEAPONS  

Microsoft Academic Search

Various types of injury of humans from thermonuclear detonations are ; discussed, including those resulting from blast, heat, and radiation. The ; characteristics of early fallout are described, and the symptoms, pathology, and ; treatment of the acute radiation syndrome occurring in response to exposure to ; fallout are outlined and discussed. Skin injuries from fallout are considered, ; especially

F. C. Pace; W. R. Waters

1961-01-01

499

Radiation cooling with. pi. pulses  

SciTech Connect

The concept of radiation cooling with ..pi.. pulses is presented and quantified with a theoretical analysis. Numerical analysis of ..pi.. pulse cooling on the hydrogen Lyman-..cap alpha.. transition is presented as an example. The cooling rate and limiting temperature are discussed and compared with steady-state radiation cooling.

Palmer, A.J.; Lam, J.F.

1986-05-01

500

The program RADLST (Radiation Listing)  

SciTech Connect

The program RADLST (Radiation Listing) is designed to calculate the nuclear and atomic radiations associated with the radioactive decay of nuclei. It uses as its primary input nuclear decay data in the Evaluated Nuclear Structure Data File (ENSDF) format. The code is written in FORTRAN 77 and, with a few exceptions, is consistent with the ANSI standard. 65 refs.

Burrows, T.W.

1988-02-29