Sample records for radiat prot dosim

  1. SWISS-PROT

    NSDL National Science Digital Library

    SWISS-PROT, provided by the Swiss Institute of Bioinformatics, is a "curated protein sequence database" that provides, with minimal redundancy and "a high level of integration with other databases," descriptions of "the function of a protein, its domains structure, post-translational modifications" and variants, as well as a host of other information. Access to the SWISS-PROT database is available via "description or identification (any word in the DE, OS, OG, GN and ID lines)," by accession number (AC line), author (RA line), citation (RL line), or full text search. Lengthy returns offer information in several dozen fields, including taxonomic hierarchy, journal references, and sequence information.

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

    PubMed

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

    2012-09-15

    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. PMID:22465017

  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. Tox-Prot, the toxin protein annotation program of the Swiss-Prot protein knowledgebase.

    PubMed

    Jungo, Florence; Bairoch, Amos

    2005-03-01

    The Tox-Prot program was initiated in order to provide the scientific community a summary of the current knowledge on animal protein toxins. The aim of this program is to systematically annotate all proteins which act as toxins and are produced by venomous and poisonous animals. Venomous animals such as snakes, scorpions, spiders, jellyfish, insects, cone snails, sea anemones, lizards, some fish, and platypus are equipped with a specialized organ to inject venom in their prey. In contrast, poisonous animals such as some fish or worms, lack such organs. Each toxin is annotated according to the quality standards of Swiss-Prot. This means providing a wealth of information that includes the description of the function, domain structure, subcellular location, tissue specificity, variants, similarities to other proteins, keywords, etc. In the framework of this program, particular care has been made to capture what is known on the function and mode of action, posttranslational modifications and 3D structural data which are all relatively abundant in the field of protein toxins. Researchers are welcome to contribute their knowledge to the scientific community by submitting relevant findings to Swiss-Prot concerning toxins at Tox-Prot@isb-sib.ch. More information on Tox-Prot can be found at http://www.expasy.org/sprot/tox-prot. PMID:15683867

  5. Automatically extracting functionally equivalent proteins from SwissProt

    PubMed Central

    McMillan, Lisa EM; Martin, Andrew CR

    2008-01-01

    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. PMID:18838004

  6. UniProt Knowledgebase: a hub of integrated protein data

    PubMed Central

    Magrane, Michele; Consortium, UniProt

    2011-01-01

    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/ PMID:21447597

  7. Activities at the Universal Protein Resource (UniProt)

    PubMed Central

    2014-01-01

    The mission of the Universal Protein Resource (UniProt) (http://www.uniprot.org) is to provide the scientific community with a comprehensive, high-quality and freely accessible resource of protein sequences and functional annotation. It integrates, interprets and standardizes data from literature and numerous resources to achieve the most comprehensive catalog possible of protein information. The central activities are the biocuration of the UniProt Knowledgebase and the dissemination of these data through our Web site and web services. 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:24253303

  8. Tox-Prot, the toxin protein annotation program of the Swiss-Prot protein knowledgebase

    Microsoft Academic Search

    Florence Jungo; Amos Bairoch

    2005-01-01

    The Tox-Prot program was initiated in order to provide the scientific community a summary of the current knowledge on animal protein toxins. The aim of this program is to systematically annotate all proteins which act as toxins and are produced by venomous and poisonous animals. Venomous animals such as snakes, scorpions, spiders, jellyfish, insects, cone snails, sea anemones, lizards, some

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

    Microsoft Academic Search

    Fabrice P. A. David; Yum Lina Yip

    2008-01-01

    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

  10. Mapping PDB chains to UniProtKB entries

    Microsoft Academic Search

    Andrew C. R. Martin

    2005-01-01

    Motivation: UniProtKB\\/SwissProt is the main resource for detailed annotations of protein sequences. This database provides a jumping- off point to many other resources through the links it provides. Among others, these include other primary databases, secondary databases, the Gene Ontology and OMIM. While a large number of links are pro- vided to PDB files, obtaining a regularly updated mapping between

  11. Radiation

    Cancer.gov

    DCEG researchers carry out a broad-based research program designed to identify, understand, and quantify the risk of cancer in populations exposed to medical, occupational, or environmental radiation. They study ionizing radiation exposures (e.g., x-rays,

  12. GraphProt: modeling binding preferences of RNA-binding proteins

    PubMed Central

    2014-01-01

    We present GraphProt, a computational framework for learning sequence- and structure-binding preferences of RNA-binding proteins (RBPs) from high-throughput experimental data. We benchmark GraphProt, demonstrating that the modeled binding preferences conform to the literature, and showcase the biological relevance and two applications of GraphProt models. First, estimated binding affinities correlate with experimental measurements. Second, predicted Ago2 targets display higher levels of expression upon Ago2 knockdown, whereas control targets do not. Computational binding models, such as those provided by GraphProt, are essential for predicting RBP binding sites and affinities in all tissues. GraphProt is freely available at http://www.bioinf.uni-freiburg.de/Software/GraphProt. PMID:24451197

  13. PROTS: A fragment based protein thermo-stability potential

    PubMed Central

    Li, Yunqi; Zhang, Jian; Tai, David; Middaugh, C. Russell; Zhang, Yang; Fang, Jianwen

    2012-01-01

    Designing proteins with enhanced thermo-stability has been a main focus of protein engineering because of its theoretical and practical significance. Despite extensive studies in the past years, a general strategy for stabilizing proteins still remains elusive. Thus effective and robust computational algorithms for designing thermo-stable proteins are in critical demand. Here we report PROTS, a sequential and structural four-residue fragment based protein thermo-stability potential. PROTS is derived from a non-redundant representative collection of thousands of thermophilic and mesophilic protein structures and a large set of point mutations with experimentally determined changes of melting temperatures. To the best of our knowledge, PROTS is the first protein stability predictor based on integrated analysis and mining of these two types of data. Besides conventional cross validation and blind testing, we introduce hypothetical reverse mutations as a means of testing the robustness of protein thermo-stability predictors. In all tests, PROTS demonstrates the ability to reliably predict mutation induced thermostability changes as well as classify thermophilic and mesophilic proteins. In addition, this white-box predictor allows easy interpretation of the factors that influence mutation induced protein stability changes at the residue level. PMID:21976375

  14. UniProt: a hub for protein information

    PubMed Central

    2015-01-01

    UniProt is an important collection of protein sequences and their annotations, which has doubled in size to 80 million sequences during the past year. This growth in sequences has prompted an extension of UniProt accession number space from 6 to 10 characters. An increasing fraction of new sequences are identical to a sequence that already exists in the database with the majority of sequences coming from genome sequencing projects. We have created a new proteome identifier that uniquely identifies a particular assembly of a species and strain or subspecies to help users track the provenance of sequences. We present a new website that has been designed using a user-experience design process. We have introduced an annotation score for all entries in UniProt to represent the relative amount of knowledge known about each protein. These scores will be helpful in identifying which proteins are the best characterized and most informative for comparative analysis. All UniProt data is provided freely and is available on the web at http://www.uniprot.org/. PMID:25348405

  15. Purification and biochemical characterization of stable alkaline protease Prot-2 from Botrytis cinerea

    Microsoft Academic Search

    Ferid Abidi; Jean-Marc Chobert; Thomas Haertlé; Mohamed Nejib Marzouki

    2011-01-01

    An extracellular alkaline protease (Prot-2) selectively secreted by Botrytis cinerea growing in medium containing Spirulina algae as inducer was purified to homogeneity by a combination of ammonium sulfate precipitation, gel filtration and ion-exchange chromatography, followed by size-exclusion chromatography. Prot-2 presented a single 30-kDa band on SDS-PAGE, which showed proteolytic activity following renaturation. Prot-2 has a monomeric structure, is active in

  16. Analysis of the tryptic search space in UniProt databases.

    PubMed

    Alpi, Emanuele; Griss, Johannes; da Silva, Alan Wilter Sousa; Bely, Benoit; Antunes, Ricardo; Zellner, Hermann; Ríos, Daniel; O'Donovan, Claire; Vizcaíno, Juan Antonio; Martin, Maria J

    2015-01-01

    In this article, we provide a comprehensive study of the content of the Universal Protein Resource (UniProt) protein data sets for human and mouse. The tryptic search spaces of the UniProtKB (UniProt knowledgebase) complete proteome sets were compared with other data sets from UniProtKB and with the corresponding International Protein Index, reference sequence, Ensembl, and UniRef100 (where UniRef is UniProt reference clusters) organism-specific data sets. All protein forms annotated in UniProtKB (both the canonical sequences and isoforms) were evaluated in this study. In addition, natural and disease-associated amino acid variants annotated in UniProtKB were included in the evaluation. The peptide unicity was also evaluated for each data set. Furthermore, the peptide information in the UniProtKB data sets was also compared against the available peptide-level identifications in the main MS-based proteomics repositories. Identifying the peptides observed in these repositories is an important resource of information for protein databases as they provide supporting evidence for the existence of otherwise predicted proteins. Likewise, the repositories could use the information available in UniProtKB to direct reprocessing efforts on specific sets of peptides/proteins of interest. In summary, we provide comprehensive information about the different organism-specific sequence data sets available from UniProt, together with the pros and cons for each, in terms of search space for MS-based bottom-up proteomics workflows. The aim of the analysis is to provide a clear view of the tryptic search space of UniProt and other protein databases to enable scientists to select those most appropriate for their purposes. PMID:25307260

  17. MultitaskProtDB: a database of multitasking proteins.

    PubMed

    Hernández, Sergio; Ferragut, Gabriela; Amela, Isaac; Perez-Pons, JosepAntoni; Piñol, Jaume; Mozo-Villarias, Angel; Cedano, Juan; Querol, Enrique

    2014-01-01

    We have compiled MultitaskProtDB, available online at http://wallace.uab.es/multitask, to provide a repository where the many multitasking proteins found in the literature can be stored. Multitasking or moonlighting is the capability of some proteins to execute two or more biological functions. Usually, multitasking proteins are experimentally revealed by serendipity. This ability of proteins to perform multitasking functions helps us to understand one of the ways used by cells to perform many complex functions with a limited number of genes. Even so, the study of this phenomenon is complex because, among other things, there is no database of moonlighting proteins. The existence of such a tool facilitates the collection and dissemination of these important data. This work reports the database, MultitaskProtDB, which is designed as a friendly user web page containing >288 multitasking proteins with their NCBI and UniProt accession numbers, canonical and additional biological functions, monomeric/oligomeric states, PDB codes when available and bibliographic references. This database also serves to gain insight into some characteristics of multitasking proteins such as frequencies of the different pairs of functions, phylogenetic conservation and so forth. PMID:24253302

  18. MultitaskProtDB: a database of multitasking proteins

    PubMed Central

    Hernández, Sergio; Ferragut, Gabriela; Amela, Isaac; Perez-Pons, JosepAntoni; Piñol, Jaume; Mozo-Villarias, Angel; Cedano, Juan; Querol, Enrique

    2014-01-01

    We have compiled MultitaskProtDB, available online at http://wallace.uab.es/multitask, to provide a repository where the many multitasking proteins found in the literature can be stored. Multitasking or moonlighting is the capability of some proteins to execute two or more biological functions. Usually, multitasking proteins are experimentally revealed by serendipity. This ability of proteins to perform multitasking functions helps us to understand one of the ways used by cells to perform many complex functions with a limited number of genes. Even so, the study of this phenomenon is complex because, among other things, there is no database of moonlighting proteins. The existence of such a tool facilitates the collection and dissemination of these important data. This work reports the database, MultitaskProtDB, which is designed as a friendly user web page containing >288 multitasking proteins with their NCBI and UniProt accession numbers, canonical and additional biological functions, monomeric/oligomeric states, PDB codes when available and bibliographic references. This database also serves to gain insight into some characteristics of multitasking proteins such as frequencies of the different pairs of functions, phylogenetic conservation and so forth. PMID:24253302

  19. enDNA-Prot: identification of DNA-binding proteins by applying ensemble learning.

    PubMed

    Xu, Ruifeng; Zhou, Jiyun; Liu, Bin; Yao, Lin; He, Yulan; Zou, Quan; Wang, Xiaolong

    2014-01-01

    DNA-binding proteins are crucial for various cellular processes, such as recognition of specific nucleotide, regulation of transcription, and regulation of gene expression. Developing an effective model for identifying DNA-binding proteins is an urgent research problem. Up to now, many methods have been proposed, but most of them focus on only one classifier and cannot make full use of the large number of negative samples to improve predicting performance. This study proposed a predictor called enDNA-Prot for DNA-binding protein identification by employing the ensemble learning technique. Experiential results showed that enDNA-Prot was comparable with DNA-Prot and outperformed DNAbinder and iDNA-Prot with performance improvement in the range of 3.97-9.52% in ACC and 0.08-0.19 in MCC. Furthermore, when the benchmark dataset was expanded with negative samples, the performance of enDNA-Prot outperformed the three existing methods by 2.83-16.63% in terms of ACC and 0.02-0.16 in terms of MCC. It indicated that enDNA-Prot is an effective method for DNA-binding protein identification and expanding training dataset with negative samples can improve its performance. For the convenience of the vast majority of experimental scientists, we developed a user-friendly web-server for enDNA-Prot which is freely accessible to the public. PMID:24977146

  20. enDNA-Prot: Identification of DNA-Binding Proteins by Applying Ensemble Learning

    PubMed Central

    Xu, Ruifeng; Zhou, Jiyun; Liu, Bin; Yao, Lin; He, Yulan; Zou, Quan; Wang, Xiaolong

    2014-01-01

    DNA-binding proteins are crucial for various cellular processes, such as recognition of specific nucleotide, regulation of transcription, and regulation of gene expression. Developing an effective model for identifying DNA-binding proteins is an urgent research problem. Up to now, many methods have been proposed, but most of them focus on only one classifier and cannot make full use of the large number of negative samples to improve predicting performance. This study proposed a predictor called enDNA-Prot for DNA-binding protein identification by employing the ensemble learning technique. Experiential results showed that enDNA-Prot was comparable with DNA-Prot and outperformed DNAbinder and iDNA-Prot with performance improvement in the range of 3.97–9.52% in ACC and 0.08–0.19 in MCC. Furthermore, when the benchmark dataset was expanded with negative samples, the performance of enDNA-Prot outperformed the three existing methods by 2.83–16.63% in terms of ACC and 0.02–0.16 in terms of MCC. It indicated that enDNA-Prot is an effective method for DNA-binding protein identification and expanding training dataset with negative samples can improve its performance. For the convenience of the vast majority of experimental scientists, we developed a user-friendly web-server for enDNA-Prot which is freely accessible to the public. PMID:24977146

  1. MS analysis and molecular characterization of Botrytis cinerea protease Prot-2. Use in bioactive peptides production.

    PubMed

    Abidi, Ferid; Aissaoui, Nayssene; Gaudin, Jean-Charles; Chobert, Jean-Marc; Haertlé, Thomas; Marzouki, Mohamed Nejib

    2013-05-01

    Prot-2 protease previously purified to homogeneity from Botrytis cinerea showed potentiality to be used in detergency and for production of bioactive peptides. To extend the characterization of Prot-2 protease, antifungal and antibacterial assays were performed in vitro using protein hydrolysates prepared from muscle of mackerel (Scomber scomborus) treated with this enzyme. The most active hydrolysate (degree of hydrolysis of 8 %) exhibited inhibition effect towards bacteria and phytopathogenic fungi, demonstrating that Prot-2 proteolysis generated bioactive peptides. Biochemical and molecular characterization of the purified Prot-2, by SDS-PAGE/Tryptic in gel-digestion and LC-MS/MS analysis, was investigated. The peptide amino acid sequence alignment search in database revealed a moderate homology between the determined amino acid sequence of Prot-2 protease and the known fungal trypsin/chymotrypsin in particular from Glomerella, Metarhizium and Streptomyces. From peptide sequence data obtained by mass spectrometry and sequences homologies, primers were defined and a cDNA fragment of 786 bp was amplified by RT-PCR. The cDNA nucleotide sequence analysis revealed an open reading frame coding for 262 amino acid residues. The deduced amino acid sequence of Prot-2 showed moderate identity with trypsin of Glomerella graminicola (74 %) and with chymotrypsin from Metarhizium anisopliae (71 %). Prot-2 exhibited a Ser protease homology and showed in addition the specific His motif of trypsin/chymotrypsin family. PMID:23494220

  2. newDNA-Prot: Prediction of DNA-binding proteins by employing support vector machine and a comprehensive sequence representation.

    PubMed

    Zhang, Yanping; Xu, Jun; Zheng, Wei; Zhang, Chen; Qiu, Xingye; Chen, Ke; Ruan, Jishou

    2014-10-01

    Identification of DNA-binding proteins is essential in studying cellular activities as the DNA-binding proteins play a pivotal role in gene regulation. In this study, we propose newDNA-Prot, a DNA-binding protein predictor that employs support vector machine classifier and a comprehensive feature representation. The sequence representation are categorized into 6 groups: primary sequence based, evolutionary profile based, predicted secondary structure based, predicted relative solvent accessibility based, physicochemical property based and biological function based features. The mRMR, wrapper and two-stage feature selection methods are employed for removing irrelevant features and reducing redundant features. Experiments demonstrate that the two-stage method performs better than the mRMR and wrapper methods. We also perform a statistical analysis on the selected features and results show that more than 95% of the selected features are statistically significant and they cover all 6 feature groups. The newDNA-Prot method is compared with several state of the art algorithms, including iDNA-Prot, DNAbinder and DNA-Prot. The results demonstrate that newDNA-Prot method outperforms the iDNA-Prot, DNAbinder and DNA-Prot methods. More specific, newDNA-Prot improves the runner-up method, DNA-Prot for around 10% on several evaluation measures. The proposed newDNA-Prot method is available at http://sourceforge.net/projects/newdnaprot/ PMID:25240115

  3. Dosimetric properties and stability of thermoluminescent foils made from LiF:Mg,Cu,P or CaSO4:Dy during long-term use

    NASA Astrophysics Data System (ADS)

    K?osowski, M.; Liszka, M.; Kope?, R.; Bilski, P.; K?dzierska, D.

    2014-11-01

    A few dosimetric systems based on thermoluminescence [TL] foils were developed in recent years (Nariyama et al. 2006, Radiat. Prot. Dosim. 120, 213-218; Olko et al. 2006 Radiat. Prot. Dosim. 118, 213-218) (Czopyk et al. 2008, Radiat. Meas., 43, 977-980; K?osowski et al. 2010, Radiat. Meas., 45, 719-721; Kope? et al. 2013, Radiat.Meas., 56, 380-383). Major application of these systems is mapping of 2D dose distribution for medical treatment plan verification, similarly to photochromic or radiochromic films. The advantage of TL foils compared to other films is their re-usability. In this work we present dosimetric properties as dose linearity and fadding of the foils made from LiF:Mg,Cu,P or CaSO4:Dy phosphors and high temperature polymers. Both types of the foils have good linearity in the range 1-20 Gy for LiF:Mg,Cu,P and 0.1-2 Gy for CaSO4:Dy. Their long term fading does not exceed 3.7% and 9% respectively. We additionally investigated effects of sensitivity loss and emission spectra for both types of the foils. One shortcoming of TL foils is that every heat process may have negative influence on their properties, causing changes of their sensitivity. Register signal of the foils after 15 readouts may be reduced by 16% of the initial. We consider that the main reason of these changes is oxidation of organic contamination on the surface and degradation of a polymer which is one of the components of the foils. Effect of sensitivity decreasing may be slowed down by proper use and cleaning detectors by solvent.

  4. The neXtProt knowledgebase on human proteins: current status.

    PubMed

    Gaudet, Pascale; Michel, Pierre-André; Zahn-Zabal, Monique; Cusin, Isabelle; Duek, Paula D; Evalet, Olivier; Gateau, Alain; Gleizes, Anne; Pereira, Mario; Teixeira, Daniel; Zhang, Ying; Lane, Lydie; Bairoch, Amos

    2015-01-01

    neXtProt (http://www.nextprot.org) is a human protein-centric knowledgebase developed at the SIB Swiss Institute of Bioinformatics. Focused solely on human proteins, neXtProt aims to provide a state of the art resource for the representation of human biology by capturing a wide range of data, precise annotations, fully traceable data provenance and a web interface which enables researchers to find and view information in a comprehensive manner. Since the introductory neXtProt publication, significant advances have been made on three main aspects: the representation of proteomics data, an extended representation of human variants and the development of an advanced search capability built around semantic technologies. These changes are presented in the current neXtProt update. PMID:25593349

  5. The SWISS-PROT protein knowledgebase and its supplement TrEMBL in 2003

    Microsoft Academic Search

    Brigitte Boeckmann; Amos Bairoch; Rolf Apweiler; Marie-claude Blatter; Anne Estreicher; Elisabeth Gasteiger; Maria Jesus Martin; Karine Michoud; Claire O'donovan; Isabelle Phan; Sandrine Pilbout; Michel Schneider

    2003-01-01

    The SWISS-PROT protein knowledgebase (http:\\/\\/ www.expasy.org\\/sprot\\/ and http:\\/\\/www.ebi.ac.uk\\/ swissprot\\/) connects amino acid sequences with the current knowledge in the Life Sciences. Each protein entry provides an interdisciplinary overview of relevant information by bringing together experi- mental results, computed features and sometimes even contradictory conclusions. Detailed expertise that goes beyond the scope of SWISS-PROT is made available via direct links to

  6. RaftProt: mammalian lipid raft proteome database

    PubMed Central

    Shah, Anup; Chen, David; Boda, Akash R.; Foster, Leonard J.; Davis, Melissa J.; Hill, Michelle M.

    2015-01-01

    RaftProt (http://lipid-raft-database.di.uq.edu.au/) is a database of mammalian lipid raft-associated proteins as reported in high-throughput mass spectrometry studies. Lipid rafts are specialized membrane microdomains enriched in cholesterol and sphingolipids thought to act as dynamic signalling and sorting platforms. Given their fundamental roles in cellular regulation, there is a plethora of information on the size, composition and regulation of these membrane microdomains, including a large number of proteomics studies. To facilitate the mining and analysis of published lipid raft proteomics studies, we have developed a searchable database RaftProt. In addition to browsing the studies, performing basic queries by protein and gene names, searching experiments by cell, tissue and organisms; we have implemented several advanced features to facilitate data mining. To address the issue of potential bias due to biochemical preparation procedures used, we have captured the lipid raft preparation methods and implemented advanced search option for methodology and sample treatment conditions, such as cholesterol depletion. Furthermore, we have identified a list of high confidence proteins, and enabled searching only from this list of likely bona fide lipid raft proteins. Given the apparent biological importance of lipid raft and their associated proteins, this database would constitute a key resource for the scientific community. PMID:25392410

  7. Combining NLP and probabilistic categorisation for document and term selection for Swiss-Prot medical annotation

    Microsoft Academic Search

    Pavel B. Dobrokhotov; Cyril Goutte; Anne-lise Veuthey; Éric Gaussier

    2003-01-01

    Motivation: Searching relevant publications for manual database annotation is a tedious task. In this paper, we apply a combination of Natural Language Processing (NLP) and probabilistic classification to re-rank documents returned by PubMed according to their relevance to Swiss- Prot annotation, and to identify significant terms in the documents. Results: With a Probabilistic Latent Categoriser (PLC) we obtained 69% recall

  8. High-quality Protein Knowledge Resource: SWISS-PROT and TrEMBL

    Microsoft Academic Search

    Claire O'donovan; Maria Jesus Martin; Alexandre Gattiker; Elisabeth Gasteiger; Amos Bairoch; Rolf Apweiler

    2002-01-01

    SWISS-PROT is a curated protein sequence database which strives to provide a high level of annotation (such as the description of the function of a protein, its domain structure, post- translational modifications, variants, etc.), a minimal level of redundancy and a high level of integration with other databases. Together with its automatically annotated supplement TrEMBL, it provides a comprehensive and

  9. Roma, 10.07.2014 Prot.n. 174/P/IV^

    E-print Network

    Di Pillo, Gianni

    Roma, 10.07.2014 Prot.n. 174/P/IV^ DIPARTIMENTO DI STUDI GIURIDICI, FILOSOFICI ED ECONOMICI IL DIRETTORE PROF.CESARE IMBRIANI VISTA la legge n.240/2010; VISTO Lo Statuto della Sapienza Università di Roma) 27.05.1981 Andrea MIGLIONICO Roma (RM) 04.04.1981 Ciro PALUMBO Roma (RM) 08.01.1978 Leonardo SURACI

  10. proteinsSTRUCTURE O FUNCTION O BIOINFORMATICS PROTS: A fragment based protein

    E-print Network

    Zhang, Yang

    online 30 August 2011 in Wiley Online Library (wileyonlinelibrary.com). DOI: 10.1002/prot.23163 ABSTRACT Applied Bioinformatics Laboratory, the University of Kansas, Lawrence, Kansas 66047 2 Center for Computational Medicine and Bioinformatics, the University of Michigan Medical School, Ann Arbor, Michigan 48109

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

    PubMed Central

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

    2009-01-01

    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. PMID:19426475

  12. Prot-Prop: J-tool to predict the subcellular location of proteins based on physiochemical characterization.

    PubMed

    Senthilkumar, Brindha; Sailo, Sangzuala; Guruswami, Gurusubramanian; Nachimuthu, Senthilkumar

    2012-12-01

    PROT-PROP is a computational tool to characterize 27 physicochemical properties of a protein along with its subcellular location (intra or extra) in a single-window application. Other significant features of this software include calculation of numerical values for hydrophobicity, hydrophilicity; composition of small and large amino acids; net hydrophobic content in terms of low/high; and Navie's algorithm to calculate theoretical pI. PROT-PROP is an easy-to-install platform independent implementation of JAVA under a user-friendly interface. It is a standalone version as a virtual appliance and source code for platforms supporting Java 1.5.0 and higher versions, and downloadable from the web http://www.mzu.edu.in/schools/biotechnology.html . PROT-PROP can run under Windows and Macintosh Operating Systems. PROT-PROP is distributed with its source code so that it may be adapted or customized, if desired. PMID:23354819

  13. The SWISS-PROT protein sequence database and its supplement TrEMBL in 2000

    Microsoft Academic Search

    Amos Bairoch; Rolf Apweiler

    2000-01-01

    SWISS-PROT is a curated protein sequence database which strives to provide a high level of annotation (such as the description of the function of a protein, its domains structure, post-translational modifications, variants, etc.), a minimal level of redundancy and high level of integration with other databases. Recent developments of the database include format and content enhancements, cross-references to additional databases,

  14. Radiation Symbols

    MedlinePLUS

    Radiation Protection Basics Health Effects Ionizing & Non-Ionizing Radiation Understanding Radiation: Radiation Symbols Radiation Protection Basics Main Page History of Radiation Protection Radiation Warning Symbols Radiation Warning Sign Gallery ...

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

    PubMed Central

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

    2013-01-01

    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/. PMID:24143170

  16. KnotProt: a database of proteins with knots and slipknots

    PubMed Central

    Jamroz, Michal; Niemyska, Wanda; Rawdon, Eric J.; Stasiak, Andrzej; Millett, Kenneth C.; Su?kowski, Piotr; Sulkowska, Joanna I.

    2015-01-01

    The protein topology database KnotProt, http://knotprot.cent.uw.edu.pl/, collects information about protein structures with open polypeptide chains forming knots or slipknots. The knotting complexity of the cataloged proteins is presented in the form of a matrix diagram that shows users the knot type of the entire polypeptide chain and of each of its subchains. The pattern visible in the matrix gives the knotting fingerprint of a given protein and permits users to determine, for example, the minimal length of the knotted regions (knot's core size) or the depth of a knot, i.e. how many amino acids can be removed from either end of the cataloged protein structure before converting it from a knot to a different type of knot. In addition, the database presents extensive information about the biological functions, families and fold types of proteins with non-trivial knotting. As an additional feature, the KnotProt database enables users to submit protein or polymer chains and generate their knotting fingerprints. PMID:25361973

  17. Characterisation of OSL and OSLN droplets for dosimetry.

    PubMed

    Nascimento, L F; D'Agostino, E; Vaniqui, A C S; Saldarriaga, C; Vanhavere, F; De Deene, Y

    2014-10-01

    In spite of considerable progress in neutron dosimetry, there is no dosemeter that is capable of measuring neutron doses independently of the neutron spectrum with good accuracy. Carbon-doped aluminium oxide (Al2O3:C) is a sensitive material for ionising radiation (beta-ray, X ray and electron) and has been used for applications in personal and medical dosimetry as an optically stimulated luminescence (OSL) dosemeter. Al2O3:C has a low sensitivity to neutron radiation; this prevents its application to neutron fields, representing a disadvantage of Al2O3:C-OSL when compared with LiF, which is used as a thermoluminescent detector. Recently an improvement for neutron dosimetry (Passmore and Kirr. Neutron response characterisation of an OSL neutron dosemeter. Radiat. Prot. Dosim. 2011; 144: 155-60) uses Al2O3:C coated with (6)Li2CO3 (OSLN),which gives the high-sensitive response as known for Al2O3:C with the advantage of being also sensitive to thermal neutrons. In this article, the authors compare small-size detectors (droplets) of Al2O3:C (OSL) and of Al2O3:C+(6)Li2CO3 (OSLN) and discuss the advantages and drawbacks of both materials, regarding size vs. response. PMID:24381203

  18. Measurement of dose equivalent distribution on-board commercial jet aircraft.

    PubMed

    Kuban?ák, J; Ambrožová, I; Ploc, O; Pachnerová Brabcová, K; Št?pán, V; Uchihori, Y

    2014-12-01

    The annual effective doses of aircrew members often exceed the limit of 1 mSv for the public due to the increased level of cosmic radiation at the flight altitudes, and thus, it is recommended to monitor them [International Commission on Radiation Protection. 1990 Recommendations of the International Commission on Radiological Protection. ICRP Publication 60. Ann. ICRP 21: (1-3), (1991)]. According to the Monte Carlo simulations [Battistoni, G., Ferrari, A., Pelliccioni, M. and Villari, R. Evaluation of the doses to aircrew members taking into consideration the aircraft structures. Adv. Space Res. 36: , 1645-1652 (2005) and Ferrari, A., Pelliccioni, M. and Villari, R. Evaluation of the influence of aircraft shielding on the aircrew exposure through an aircraft mathematical model. Radiat. Prot. Dosim. 108: (2), 91-105 (2004)], the ambient dose equivalent rate H?*(10) depends on the location in the aircraft. The aim of this article is to experimentally evaluate H?*(10) on-board selected types of aircraft. The authors found that H?*(10) values are higher in the front and the back of the cabin and lesser in the middle of the cabin. Moreover, total dosimetry characteristics obtained in this way are in a reasonable agreement with other data, in particular with the above-mentioned simulations. PMID:24344348

  19. MAPS BANDING Sheet Location Band Size Year 2012 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS BANDING Sheet Location Band Size Year 2012 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP New Band N Local 4 Skull NUMBER SPECIES ALPHA CODE AGE HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR

  20. MAPS RECAPTURES Sheet Location Band Size R Year 2012 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS RECAPTURES Sheet Location Band Size R Year 2012 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Recapture R Local 4 Skull ALPHA CODE AGE HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR JUV.PL. PRI

  1. MAPS UNBANDED Sheet Location Band Size U Year 2013 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS UNBANDED Sheet Location Band Size U Year 2013 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Only use 'U' for Local 4 Skull HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR JUV.PL. PRI.COVS SEC

  2. MAPS UNBANDED Sheet Location Band Size U Year 2012 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS UNBANDED Sheet Location Band Size U Year 2012 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Only use 'U' for Local 4 Skull HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR JUV.PL. PRI.COVS SEC

  3. MAPS RECAPTURES Sheet Location Band Size R Year Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS RECAPTURES Sheet Location Band Size R Year Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Recapture R Local 4 Skull ALPHA CODE AGE HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR JUV.PL. PRI

  4. MAPS UNBANDED Sheet Location Band Size U Year 2011 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS UNBANDED Sheet Location Band Size U Year 2011 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Only use 'U' for Local 4 Skull BAND NUMBER SPECIES ALPHA CODE AGE HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT

  5. MAPS RECAPTURES Sheet Location Band Size R Year 2013 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS RECAPTURES Sheet Location Band Size R Year 2013 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Recapture R Local 4 Skull ALPHA CODE AGE HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR JUV.PL. PRI

  6. MAPS BANDING Sheet Location Band Size Year 2013 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS BANDING Sheet Location Band Size Year 2013 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP New Band N Local 4 Skull NUMBER SPECIES ALPHA CODE AGE HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR

  7. MAPS BANDING Sheet Location Band Size Year Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS BANDING Sheet Location Band Size Year Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP New Band N Local 4 Skull S Feather NUMBER SPECIES ALPHA CODE AGE HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR

  8. MAPS UNBANDED Sheet Location Band Size U Year 2014 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS UNBANDED Sheet Location Band Size U Year 2014 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Only use 'U' for Local 4 Skull HOW AGED SEX HOW SEXED SKULL CL.PROT. BR.PATCH FAT BODYMLT FFMOLT FFWEAR JUV.PL. PRI.COVS SEC

  9. MAPS RECAPTURES Sheet Location Band Size R Year 2011 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MAPS RECAPTURES Sheet Location Band Size R Year 2011 Page # CODE AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Recapture R Local 4 Skull BANDER'S INITIALS CODE BAND NUMBER SPECIES ALPHA CODE AGE HOW AGED SEX HOW SEXED SKULL CL.PROT. BR

  10. Determination of thermoluminescence kinetic parameters of terbium-doped zirconium oxide

    NASA Astrophysics Data System (ADS)

    Rivera, T.; Azorín, J.; Falcony, C.; Martínez, E.; García, M.

    2001-06-01

    In recent years considerable importance has been attached to zirconium oxide doped with rare earth (ZrO 2 : RE) thin films due to their desirable characteristics for use in UV dosimetry. In our laboratories we have developed a method to prepare ZrO 2 : RE thin films. Dosimetric characteristics of these materials have been reported previously (Azorin et al., Radiat. Meas. 29 (1998) 315; Radiat. Prot. Dosim. 85 (1999) 317) and results of these have stimulated continued development and analysis of the thermoluminescence mechanism. Two important parameters to be determined in TL studies are the activation energy ( E) and the frequency factor ( s). This paper presents the results of determining kinetic parameters of terbium-doped zirconium oxide (ZrO 2 : Tb) thin films, exposed to 260 nm UV light, using the Lushchik (Sov. Phys. JETF 3 (1956) 390) and Chen (J. Appl. Phys. 40 (1969) 570; J. Electrochem. Soc. 166 (1969) 1254) methods. Kinetic analysis of the glow curve shows second order kinetics for both the first and second glow peaks.

  11. Unique composite hematolymphoid tumor consisting of a pro-T lymphoblastic lymphoma and an indeterminate dendritic cell tumor: evidence for divergent common progenitor cell differentiation.

    PubMed

    Buser, Lorenz; Bihl, Michel; Rufle, Alex; Mickys, Ugnius; Tavoriene, Ilma; Griskevicius, Laimonas; Tzankov, Alexandar

    2014-01-01

    Until recently, hematopoietic neoplasms were considered monoclonal proliferations belonging to one cell lineage. In the last years, evidence for transdifferentiation from one cell lineage to another or divergent common progenitor cell differentiation has accumulated, mainly based on composite hematolymphoid tumors, sharing common genetic abnormalities. We report the case of a 59-year-old woman with a composite pro-T lymphoblastic lymphoma (LBL) and indeterminate dendritic cell tumor infiltrating the lymph nodes, bone marrow and stomach. Genetic analyses revealed that both cell populations bore +21, while a G13D mutation of the NRAS gene and monosomy 18 were detected only in the pro-T LBL. The synchronous appearance of two distinct uncommon hematolymphoid tumors in the same patient, recurrent at three different anatomic locations, with an identifiable common genetic denominator, namely +21, but also with unique genetic anomalies in the pro-T LBL raises the hypothesis of a divergent common progenitor cell differentiation. PMID:25228298

  12. Preliminary modeling of BNCT beam tube on IRT in Sofia.

    PubMed

    Belousov, S; Ilieva, K

    2009-07-01

    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

  13. 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. The therapy ...

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

    PubMed

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

    2010-08-01

    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

  15. Radiation dosimetry.

    PubMed Central

    Cameron, J

    1991-01-01

    This article summarizes 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 radiation risk unit to make radiation risks more understandable to nonspecialists. PMID:2040250

  16. Radiative cooler. [spacecraft radiators

    NASA Technical Reports Server (NTRS)

    Petrick, S. W.; Garcia, R. D. (inventors)

    1984-01-01

    A method and radiative cooling device for use in passively cooling spaces is described. It is applicable to any level of thermal radiation in vacuum and to high-intensity thermal radiation in non-vacuum environments. The device includes an enclosure nested in a multiplicity of thin, low-emittance, highly-reflective shields. The shields are suspended in a casing in mutual angular relation and having V-shaped spaces defined therebetween for redirecting, by reflection, toward the large openings of the V-shaped spaces, thermal radiation entering the sides of the shields, and emitted to the spaces, whereby successively reduced quantities of thermal radiation are reflected by the surfaces along substantially parallel paths extended through the V-shaped spaces to a common heat sink such as the cold thermal background of space.

  17. Radiation detector

    SciTech Connect

    Rifu, T.

    1984-10-16

    A radiation detector adapted to be used with a computerized tomographic apparatus, wherein filters prepared from a radiation-absorbing material are provided on the outside of a radiation-permeable window in the positions facing radiation-detecting cells. The filters compensate for differences between the radiation-detecting properties of the detection cells, thereby equalizing said radiation-detecting properties.

  18. PROTS-RF: A Robust Model for Predicting Mutation-Induced Protein Stability Changes

    PubMed Central

    Li, Yunqi; Fang, Jianwen

    2012-01-01

    The ability to improve protein thermostability via protein engineering is of great scientific interest and also has significant practical value. In this report we present PROTS-RF, a robust model based on the Random Forest algorithm capable of predicting thermostability changes induced by not only single-, but also double- or multiple-point mutations. The model is built using 41 features including evolutionary information, secondary structure, solvent accessibility and a set of fragment-based features. It achieves accuracies of 0.799,0.782, 0.787, and areas under receiver operating characteristic (ROC) curves of 0.873, 0.868 and 0.862 for single-, double- and multiple- point mutation datasets, respectively. Contrary to previous suggestions, our results clearly demonstrate that a robust predictive model trained for predicting single point mutation induced thermostability changes can be capable of predicting double and multiple point mutations. It also shows high levels of robustness in the tests using hypothetical reverse mutations. We demonstrate that testing datasets created based on physical principles can be highly useful for testing the robustness of predictive models. PMID:23077576

  19. MoonProt: a database for proteins that are known to moonlight

    PubMed Central

    Mani, Mathew; Chen, Chang; Amblee, Vaishak; Liu, Haipeng; Mathur, Tanu; Zwicke, Grant; Zabad, Shadi; Patel, Bansi; Thakkar, Jagravi; Jeffery, Constance J.

    2015-01-01

    Moonlighting proteins comprise a class of multifunctional proteins in which a single polypeptide chain performs multiple biochemical functions that are not due to gene fusions, multiple RNA splice variants or pleiotropic effects. The known moonlighting proteins perform a variety of diverse functions in many different cell types and species, and information about their structures and functions is scattered in many publications. We have constructed the manually curated, searchable, internet-based MoonProt Database (http://www.moonlightingproteins.org) with information about the over 200 proteins that have been experimentally verified to be moonlighting proteins. The availability of this organized information provides a more complete picture of what is currently known about moonlighting proteins. The database will also aid researchers in other fields, including determining the functions of genes identified in genome sequencing projects, interpreting data from proteomics projects and annotating protein sequence and structural databases. In addition, information about the structures and functions of moonlighting proteins can be helpful in understanding how novel protein functional sites evolved on an ancient protein scaffold, which can also help in the design of proteins with novel functions. PMID:25324305

  20. Annotation of protein residues based on a literature analysis: cross-validation against UniProtKb

    PubMed Central

    Nagel, Kevin; Jimeno-Yepes, Antonio; Rebholz-Schuhmann, Dietrich

    2009-01-01

    Background A protein annotation database, such as the Universal Protein Resource knowledge base (UniProtKb), is a valuable resource for the validation and interpretation of predicted 3D structure patterns in proteins. Existing studies have focussed on point mutation extraction methods from biomedical literature which can be used to support the time consuming work of manual database curation. However, these methods were limited to point mutation extraction and do not extract features for the annotation of proteins at the residue level. Results This work introduces a system that identifies protein residues in MEDLINE abstracts and annotates them with features extracted from the context written in the surrounding text. MEDLINE abstract texts have been processed to identify protein mentions in combination with taxonomic species and protein residues (F1-measure 0.52). The identified protein-species-residue triplets have been validated and benchmarked against reference data resources (UniProtKb, average F1-measure of 0.54). Then, contextual features were extracted through shallow and deep parsing and the features have been classified into predefined categories (F1-measure ranges from 0.15 to 0.67). Furthermore, the feature sets have been aligned with annotation types in UniProtKb to assess the relevance of the annotations for ongoing curation projects. Altogether, the annotations have been assessed automatically and manually against reference data resources. Conclusion This work proposes a solution for the automatic extraction of functional annotation for protein residues from biomedical articles. The presented approach is an extension to other existing systems in that a wider range of residue entities are considered and that features of residues are extracted as annotations. PMID:19758468

  1. Radiation therapy

    MedlinePLUS

    ... Because radiation is most harmful to quickly growing cells, radiation therapy damages cancer cells more than normal cells. This ... cells from growing and dividing, and leads to cell death. Radiation therapy is used to fight many types of cancer . ...

  2. Radiation sickness

    MedlinePLUS

    ... to determine the amount of radiation exposure from nuclear accidents, the best signs of the severity of the ... to high doses of radiation such as a nuclear power plant accidents Exposure to excessive radiation for medical treatments

  3. 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, ...

  4. Radiation Emergencies

    MedlinePLUS

    ... Simulation Tools CDC Response, Japan 2011 Specific Hazards Radiation Emergencies Language: English Español (Spanish) Recommend on Facebook ... loved ones, and your pets. Learn More » Radiation and Your Health Radiation can affect the body ...

  5. Radiation Laws

    NSDL National Science Digital Library

    Department of Physics and Astronomy

    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.

  6. Space Radiation

    NASA Technical Reports Server (NTRS)

    Wu, Honglu

    2006-01-01

    Astronauts receive the highest occupational radiation exposure. Effective protections are needed to ensure the safety of astronauts on long duration space missions. Increased cancer morbidity or mortality risk in astronauts may be caused by occupational radiation exposure. Acute and late radiation damage to the central nervous system (CNS) may lead to changes in motor function and behavior, or neurological disorders. Radiation exposure may result in degenerative tissue diseases (non-cancer or non-CNS) such as cardiac, circulatory, or digestive diseases, as well as cataracts. Acute radiation syndromes may occur due to occupational radiation exposure.

  7. Radiation Therapy

    MedlinePLUS

    ... or hospital). Then a large machine called a simulator will deliver the exact amount of radiation necessary ... receive the daily dose of radiation. While the simulator is on, you'll have to lie very ...

  8. Radiation Therapy

    MedlinePLUS

    ... benign (not cancerous) or malignant (cancerous). Radiation therapy kills cancer cells and keeps them from growing and ... deliver the exact amount of radiation necessary to kill the cells. It usually takes only a few ...

  9. Radiation Therapy

    MedlinePLUS

    ... for e-updates Please leave this field empty Radiation Therapy SHARE Share on Facebook Preview your comments ... Treatment and Care > Treatments Listen The goal of radiation therapy is to destroy or stop brain tumor ...

  10. Radiation Protection

    NASA Astrophysics Data System (ADS)

    Grupen, Claus

    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.

  11. Radiation Chemistry

    NASA Astrophysics Data System (ADS)

    Wojnárovits, L.

    Ionizing radiation causes chemical changes in the molecules of the interacting medium. The initial molecules change to new molecules, resulting in changes of the physical, chemical, and eventually biological properties of the material. For instance, water decomposes to its elements H2 and O2. In polymers, degradation and crosslinking take place. In biopolymers, e.g., DNS strand breaks and other alterations occur. Such changes are to be avoided in some cases (radiation protection), however, in other cases they are used for technological purposes (radiation processing). This chapter introduces radiation chemistry by discussing the sources of ionizing radiation (radionuclide sources, machine sources), absorption of radiation energy, techniques used in radiation chemistry research, and methods of absorbed energy (absorbed dose) measurements. Radiation chemistry of different classes of inorganic (water and aqueous solutions, inorganic solids, ionic liquids (ILs)) and organic substances (hydrocarbons, halogenated compounds, polymers, and biomolecules) is discussed in concise form together with theoretical and experimental backgrounds. An essential part of the chapter is the introduction of radiation processing technologies in the fields of polymer chemistry, food processing, and sterilization. The application of radiation chemistry to nuclear technology and to protection of environment (flue gas treatment, wastewater treatment) is also discussed.

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

    SciTech Connect

    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

    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.

  13. Hawking radiation

    NASA Astrophysics Data System (ADS)

    Parentani, Renaud; Spindel, Philippe

    2011-12-01

    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.

  14. Radiator technology

    NASA Technical Reports Server (NTRS)

    Juhasz, Albert J.

    1993-01-01

    Radiator technology is discussed in the context of the Civilian Space Technology Initiative's (CSTI's) high capacity power-thermal management project. The CSTI project is a subset of a project to develop a piloted Mars nuclear electric propulsion (NEP) vehicle. The following topics are presented in vugraph form: advanced radiator concepts; heat pipe codes and testing; composite materials; radiator design and integration; and surface morphology.

  15. RADIATION PROTECTION

    Microsoft Academic Search

    1958-01-01

    The basis of radiation protection is the limitation of the dose received. ; In specifying permissible levels of irradiation the factors to be considered are ; (1) the source of the radiation, external or internal, (2) exposure to total or ; partial irradiation, and (3) the biological effects involved, somatic or genetic. ; The basic principles of rsdiation protection bassd

  16. Understanding Radiation.

    ERIC Educational Resources Information Center

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

    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…

  17. Radiation Exposure

    MedlinePLUS

    ... 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 your risk ...

  18. Diffuse radiation

    NASA Technical Reports Server (NTRS)

    1981-01-01

    A diffuse celestial radiation which is isotropic at least on a course scale were measured from the soft X-ray region to about 150 MeV, at which energy the intensity falls below that of the galactic emission for most galactic latitudes. The spectral shape, the intensity, and the established degree of isotropy of this diffuse radiation already place severe constraints on the possible explanations for this radiation. Among the extragalactic theories, the more promising explanations of the isotropic diffuse emission appear to be radiation from exceptional galaxies from matter antimatter annihilation at the boundaries of superclusters of galaxies of matter and antimatter in baryon symmetric big bang models. Other possible sources for extragalactic diffuse gamma radiation are discussed and include normal galaxies, clusters of galaxies, primordial cosmic rays interacting with intergalactic matter, primordial black holes, and cosmic ray leakage from galaxies.

  19. Understanding how and why the Gene Ontology and its annotations evolve: the GO within UniProt

    PubMed Central

    2014-01-01

    The Gene Ontology Consortium (GOC) is a major bioinformatics project that provides structured controlled vocabularies to classify gene product function and location. GOC members create annotations to gene products using the Gene Ontology (GO) vocabularies, thus providing an extensive, publicly available resource. The GO and its annotations to gene products are now an integral part of functional analysis, and statistical tests using GO data are becoming routine for researchers to include when publishing functional information. While many helpful articles about the GOC are available, there are certain updates to the ontology and annotation sets that sometimes go unobserved. Here we describe some of the ways in which GO can change that should be carefully considered by all users of GO as they may have a significant impact on the resulting gene product annotations, and therefore the functional description of the gene product, or the interpretation of analyses performed on GO datasets. GO annotations for gene products change for many reasons, and while these changes generally improve the accuracy of the representation of the underlying biology, they do not necessarily imply that previous annotations were incorrect. We additionally describe the quality assurance mechanisms we employ to improve the accuracy of annotations, which necessarily changes the composition of the annotation sets we provide. We use the Universal Protein Resource (UniProt) for illustrative purposes of how the GO Consortium, as a whole, manages these changes. PMID:24641996

  20. Synchrotron Radiation

    SciTech Connect

    Wiedemann, Helmut

    2003-08-11

    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.

  1. Radiation Balance

    NSDL National Science Digital Library

    Radiation Balance challenges students to "become a meteorologist" and make predictions about the relationships among ground cover, time of day, altitude and temperature. It is a simulation of radiation processes in the earth's atmosphere caused by solar, terrestrial, and atmospheric radiation transfer. Students analyze temperature data measured by a balloon (radiosonde) that they "launch" both in the morning and evening over four types of terrain (sand, plowed field, grass or fresh snow). As the balloon is dragged and dropped to various heights in the simulated atmosphere, the temperatures at these altitudes are automatically plotted on a graph. Several temperature profiles may be plotted concurrently to compare differences before clearing the graph.

  2. UV Radiation

    NSDL National Science Digital Library

    U.S. Environmental Protection Agency (; )

    2008-04-25

    The sun radiates energy over a broad spectrum of wavelengths. Ultraviolet (UV) radiation, which has a shorter wavelength than either visible blue or violet light, is responsible for sunburn and other adverse health effects. Fortunately for life on Earth, our atmospheres stratospheric ozone layer shields us from most UV radiation. What gets through the ozone layer, however, can cause the following problems, particularly for people who spend substantial time outdoors: Skin cancer, Suppression of the immune system, Cataracts, and Premature aging of the skin.Because of these serious health effects, you should limit your exposure to UVradiation and protect yourself when outdoors.

  3. A Solid-Phase Immunostaining Protocol for High-Resolution Imagi... http://www.cshprotocols.org/cgi/content/full/2007/12/pdb.prot4771?... 1 of 8 6/6/07 12:25 PM

    E-print Network

    Condron, Barry

    Hypodermic needle Image editing software (e.g., Adobe Photoshop) Kimwipes Petri dishes (35 x 10 mm) Petroleum.prot4771 Protocol A Solid-Phase Immunostaining Protocol for High-Resolution Imaging of Delicate Structures in preparation for high-resolution fluorescent imaging of fine structures in the central nervous system (CNS

  4. MoSI BANDING Sheet Location Band Size Season (e.g. 2009-10) Page # CODE SEX AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MoSI BANDING Sheet Location Band Size Season (e.g. 2009-10) Page # CODE SEX AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP New Band N Male L Leave blank if you didn't look Predation P Dead D at that feather tract. DATE BANDER'S INITIALS

  5. Healthful radiation

    SciTech Connect

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

    1997-01-01

    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.

  6. Radiation Therapy

    MedlinePLUS

    ... energy to the tumor, while sparing nearby normal tissue. In this way, the risk of the common side effects of radiation to the liver, such as nausea, ulcers in the stomach or intestines, are minimized. In general, smaller liver ...

  7. RADIATION SAFETY TRAINING MANUAL Radiation Safety Office

    E-print Network

    Sibille, Etienne

    RADIATION SAFETY TRAINING MANUAL Radiation Safety Office 130 DeSoto Street G-7 Parran with sources of ionizing radiation are required to be instructed in the basic principles of radiation protection and the potential risks of ionizing radiation. Radiation Safety Office personnel provide

  8. Hoja para Aves sin Anillar MoSI Localidad Tamao de anillo U Temporada (p.ej. 2009-10) Pgina # CDIGO SEXO EDAD COMO DETERMINAR LA EDAD Y EL SEXO CRNEO PROT. CLOAC. PARCH. DE INC. GRASA MUDA CUERP. MUDA PL. VUEL. DESGAS. VUEL. LIM. DE MUDA Y PL. TENDENCIA

    E-print Network

    DeSante, David F.

    # C�DIGO SEXO EDAD COMO DETERMINAR LA EDAD Y EL SEXO CRÁNEO PROT. CLOAC. PARCH. DE INC. GRASA MUDA CUERP SEXO ALFA DELA ESPECIE ANILLOS DE COLORES Lesión vieja, cicatrizad. Herida o enfermedad INICIALESDEL

  9. Radiation Therapy (For Parents)

    MedlinePLUS

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

  10. Synchrotron radiation

    SciTech Connect

    Knotek, M.L.

    1987-01-01

    Synchrotron radiation has had a revolutionary effect on a broad range of scientific studies, from physics, chemistry and metallurgy to biology, medicine and geoscience. The situation during the last decade has been one of very rapid growth, there is a great vitality to the field and a capability has been given to a very broad range of scientific disciplines which was undreamed of just a decade or so ago. Here we will discuss some of the properties of synchrotron radiation that makes it so interesting and something of the sources in existence today including the National Synchrotron Light Source (NSLS). The NSLS is one of the new facilities built specifically for synchrotron radiation research and the model that was developed there for involvement of the scientific community is a good one which provides some good lessons for these facilities and others.

  11. Radiation receiver

    DOEpatents

    Hunt, Arlon J. (Oakland, CA)

    1983-01-01

    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.

  12. Radiation receiver

    DOEpatents

    Hunt, A.J.

    1983-09-13

    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.

  13. Radiation Fog

    NSDL National Science Digital Library

    2014-09-14

    This module 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. Tom Dulong of the National Weather Service Center Weather Service Unit (CWSU) in Longmont, Colorado is the Principal Science Advisor for this module, and Dr. Paul Croft, Meteorology Program Coordinator for Jackson State University, provided additional scientific review and guidance. The module's format was updated and republished on May 20, 2009.

  14. Appendix G. Radiation Appendix G. Radiation

    E-print Network

    Pennycook, Steve

    Appendix G. Radiation #12;#12;Appendix G. Radiation This appendix presents basic facts about radiation. The information is intended to be a basis for un- derstanding the potential doses associated of radiation and its effects on the environment and biological systems. Radiation comes from natural and human

  15. Radiation acoustics

    Microsoft Academic Search

    L M Lyamshev

    1992-01-01

    A review is given of results of research on the excitation of sound in a condensed medium by penetrating radiation (beams of protons, electrons, photons, etc.) that is both modulated in intensity and pulsed. The thermoradiation (thermoelastic) mechanism is examined in detail when the volume density of the energy released in the medium is not great and no phase changes

  16. Radiation retinopathy

    SciTech Connect

    Parker, R.G.; Withers, H.R.

    1988-01-01

    A letter to the editor discusses the effectiveness and risk of radiation treatment of Grave's ophthalmopathy. The authors are unable to document a single instance in which retinopathy can be attributed to therapy with a total dose of 2000 cGy when delivered in daily increments of 180 to 200 cGy.

  17. Sound Radiation from Cylindrical Radiators

    NSDL National Science Digital Library

    Dr. Dan Russell

    The following animations illustrate the radiation of sound waves from a vibrating source in 2-D. The source is a long cylinder which is oscillating in the radial direction only (all vibrations along the length of the cylinder are ignored). In particular, the animations show the vibration of the cylinder in its various modes and the resulting particle displacements of the surrounding fluid.

  18. Acute Radiation Syndrome

    MedlinePLUS

    ... Tools CDC Response, Japan 2011 Specific Hazards Acute Radiation Syndrome (ARS): A Fact Sheet for the Public ... is called the radiation dose. People exposed to radiation will get ARS only if: The radiation dose ...

  19. Calculate Your Radiation Dose

    MedlinePLUS

    ... Ionizing & Non-Ionizing Radiation Understanding Radiation: Calculate Your Radiation Dose Health Effects Main Page Exposure Pathways Calculate ... of the US do you live in? Internal radiation (in your body): From food and water, (e. ...

  20. 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 can be used in several ...

  1. Radiation Oncology Treatment Team

    MedlinePLUS

    ... Prostate Skin Upper GI Latest Research Find a Radiation Oncologist Last Name: Facility: City: State: Zip Code: ... who specializes in using radiation to treat cancer . Radiation Oncologists Radiation oncologists are the doctors who will ...

  2. Radiation Protection

    NSDL National Science Digital Library

    Science Update (AAAS; )

    2008-05-01

    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.

  3. Fundamental Radiation Concepts

    E-print Network

    Slatton, Clint

    Fundamental Radiation Concepts Alyson Cieply University of Florida Environmental Health and Safety Radiation Control #12;What is radiation? Radiation is energy that travels through space or matter in the form of a particle or wave The effect radiation has on matter depends on the type of radiation and how

  4. CutProtFam-Pred: detection and classification of putative structural cuticular proteins from sequence alone, based on profile hidden Markov models.

    PubMed

    Ioannidou, Zoi S; Theodoropoulou, Margarita C; Papandreou, Nikos C; Willis, Judith H; Hamodrakas, Stavros J

    2014-09-01

    The arthropod cuticle is a composite, bipartite system, made of chitin ?laments embedded in a proteinaceous matrix. The physical properties of cuticle are determined by the structure and the interactions of its two major components, cuticular proteins (CPs) and chitin. The proteinaceous matrix consists mainly of structural cuticular proteins. The majority of the structural proteins that have been described to date belong to the CPR family, and they are identified by the conserved R&R region (Rebers and Riddiford Consensus). Two major subfamilies of the CPR family RR-1 and RR-2, have also been identified from conservation at sequence level and some correlation with the cuticle type. Recently, several novel families, also containing characteristic conserved regions, have been described. The package HMMER v3.0 (http://hmmer.janelia.org/) was used to build characteristic pro?le Hidden Markov Models based on the characteristic regions for 8 of these families, (CPF, CPAP3, CPAP1, CPCFC, CPLCA, CPLCG, CPLCW, Tweedle). In brief, these families can be described as having: CPF (a conserved region with 44 amino acids); CPAP1 and CPAP-3 (analogous to peritrophins, with 1 and 3 chitin-binding domains, respectively); CPCFC (2 or 3 C-x(5)-C repeats); and four of five low complexity (LC) families, each with characteristic domains. Using these models, as well as the models previously created for the two major subfamilies of the CPR family, RR-1 and RR-2 (Karouzou et al., 2007), we developed CutProtFam-Pred, an on-line tool (http://bioinformatics.biol.uoa.gr/CutProtFam-Pred) that allows one to query sequences from proteomes or translated transcriptomes, for the accurate detection and classification of putative structural cuticular proteins. The tool has been applied successfully to diverse arthropod proteomes including a crustacean (Daphnia pulex) and a chelicerate (Tetranychus urticae), but at this taxonomic distance only CPRs and CPAPs were recovered. PMID:24978609

  5. Radiation protection in space.

    PubMed

    Reitz, G; Facius, R; Sandler, H

    1995-01-01

    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

  6. Shortwave Radiation

    NASA Technical Reports Server (NTRS)

    Klassen, Steve; Bugbee, Bruce

    2005-01-01

    Accurate shortwave radiation data is critical to evapotranspiration (ET) models used for developing irrigation schedules to optimize crop production while saving water, minimizing fertilizer, herbicide, and pesticide applications, reducing soil erosion, and protecting surface and ground water quality. Low cost silicon cell pyranometers have proven to be sufficiently accurate and robust for widespread use in agricultural applications under unobstructed daylight conditions. More expensive thermopile pyranometers are required for use as calibration standards and measurements under light with unique spectral properties (electric lights, under vegetation, in greenhouses and growth chambers). Routine cleaning, leveling, and annual calibration checks will help to ensure the integrity of long-term data.

  7. Radiating gravastars

    SciTech Connect

    Chan, R. [Coordenação de Astronomia e Astrofísica, Observatório Nacional, Rua General José Cristino, 77, São Cristóvão 20921-400, Rio de Janeiro, RJ (Brazil); Silva, M.F.A. da [Departamento de Física Teórica, Instituto de Física, Universidade do Estado do Rio de Janeiro, Rua São Francisco Xavier 524, Maracanã 20550-900, Rio de Janeiro - RJ (Brazil); Rocha, Jaime F. Villas da [Instituto de Biociências, Departamento de Ciências Naturais, Universidade Federal do Estado do Rio de Janeiro, Av. Pasteur 458, Urca, CEP 22290-240, Rio de Janeiro, RJ (Brazil); Wang, Anzhong, E-mail: chan@on.br, E-mail: mfasnic@gmail.com, E-mail: jfvroch@pq.cnpq.br, E-mail: anzhong_wang@baylor.edu [GCAP-CASPER, Department of Physics, Baylor University, Waco, TX 76798 (United States)

    2011-10-01

    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.

  8. Adaptors for radiation detectors

    SciTech Connect

    Livesay, Ronald Jason

    2014-04-22

    Described herein are adaptors and other devices for radiation detectors that can be used to make accurate spectral measurements of both small and large bulk sources of radioactivity, such as building structures, soils, vessels, large equipment, and liquid bodies. Some exemplary devices comprise an adaptor for a radiation detector, wherein the adaptor can be configured to collimate radiation passing through the adapter from an external radiation source to the radiation detector and the adaptor can be configured to enclose a radiation source within the adapter to allow the radiation detector to measure radiation emitted from the enclosed radiation source.

  9. Radiation dosimeters

    DOEpatents

    Hoelsher, James W. (Pullman, WA); Hegland, Joel E. (Pullman, WA); Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA)

    1992-01-01

    Radiation dosimeters and dosimeter badges. The dosimeter badges include first and second parts which are connected to join using a securement to produce a sealed area in which at least one dosimeter is held and protected. The badge parts are separated to expose the dosimeters to a stimulating laser beam used to read dose exposure information therefrom. The badge is constructed to allow automated disassembly and reassembly in a uniquely fitting relationship. An electronic memory is included to provide calibration and identification information used during reading of the dosimeter. Dosimeter mounts which reduce thermal heating requirements are shown. Dosimeter constructions and production methods using thin substrates and phosphor binder-layers applied thereto are also taught.

  10. Radiation Insulation

    NASA Technical Reports Server (NTRS)

    1995-01-01

    The Apollo and subsequent spacecraft have had highly effective radiation barriers; made of aluminized polymer film, they bar or let in heat to maintain consistent temperatures inside. Tech 2000, formerly Quantum International Corporation used the NASA technology in its insulating materials, Super "Q" Radiant Barrier, for home, industry and mobile applications. The insulation combines industrial aluminum foil overlaid around a core of another material, usually propylene or mylar. The outer layer reflects up to 97 percent of heat; the central layer creates a thermal break in the structure and thus allows low radiant energy emission. The Quantum Cool Wall, used in cars and trucks, takes up little space while providing superior insulation, thus reducing spoilage and costs. The panels can also dampen sound and engine, exhaust and solar heat.

  11. Radiation Insulation

    NASA Technical Reports Server (NTRS)

    1993-01-01

    An aluminized polymer film is a highly effective radiation barrier for both manned and unmanned spacecraft. Variations of this space-devised material are also used as an energy conservation technique for homes and offices. One commercial company, Tech 2000 (formerly Buckeye Radiant Barrier), markets 'Super R' Radiant Barrier, which finds its origins in the Apollo Mission programs. The material is placed between wall studs and exterior facing before siding or in new roof installation, between roof support and roof sheathing. Successful retrofit installations have included schools and shrink wrap ovens. The radiant barrier blocks 95 percent of radiant energy, thus retaining summer heat and blocking winter cold. Suppliers claim utility bill reductions of 20 percent or more.

  12. Radiation Safety September 2013

    E-print Network

    California at Irvine, University of

    Radiation Safety Manual September 2013 Office of Environment, Health & Safety #12;RADIATION SAFETY of ionizing radiation as a valuable tool to extend fundamental knowledge. These activities are an important of radiation-producing machines and radioactive materials attests to the success of its radiation safety

  13. Radiation Contamination Versus Exposure

    MedlinePLUS

    RADIATION CONTAMINATION VERSUS EXPOSURE EXTERNAL CONTAMINATION External contamination occurs when radioactive material comes into contact with a ... radioactive materials can accumulate in different body organs. RADIATION EXPOSURE Another word for radiation exposure is irradiation. ...

  14. [Neurotoxicity of radiation].

    PubMed

    Suzuki, Keiji

    2015-01-01

    It is well-known that the central nervous system is thoroughly resistant to ionizing radiation as high-dose radiation exposure is required for causing neuronal death. In contrast, recent studies have revealed that the hippocampus, which could be the main organ involved in disorder of higher brain functions after radiation therapy, contains radiation-sensitive cell fractions. In this paper, the basics of radiation effects and the molecular mechanism of neurotoxicity of radiation have been reviewed and discussed. PMID:25585436

  15. Solar radiation resource assessment

    SciTech Connect

    Not Available

    1990-11-01

    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.

  16. Advanced radiator concepts

    NASA Technical Reports Server (NTRS)

    Diem-Kirsop, P. S.

    1985-01-01

    The liquid droplet radiator and the liquid belt radiator currently under study by the NASA LeRC are discussed. These advanced concepts offer benefits in reduced mass, compact stowage, and ease of deployment. Operation and components of the radiators are described, heat transfer characteristics are discussed, and critical technologies are identified. The impact of the radiators on large power systems is also assessed.

  17. Radiation detection and measurement

    Microsoft Academic Search

    Glenn F. Knoll

    1979-01-01

    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.

  18. Radiation and People

    ERIC Educational Resources Information Center

    Freilich, Florence G.

    1970-01-01

    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)

  19. Radiation Protection Concepts

    Microsoft Academic Search

    D. Harder; V. Klener; W. Atwell; M. Beno; E. W. Breitbart; C. Cremer; R. J. M. Fry; R. Greinert; D.-P. Häder; P. Knuschke; G. Obe; G. Reitz; P. Rettberg; F. Spurny; H. Tanooka; L. Tomášek; B. Volkmer

    \\u000a Environmental radiation exposure is here understood to be the exposure to natural or man-made sources of ionizing or non-ionizing radiation due to private\\u000a or professional activities, including radiation exposure incurred by medical examinations and treat­ments. Ultraviolet light\\u000a (UV) will be treated here as the main source of risk for non-ionizing radiation. Radiation protection concepts are the main strategies devised to

  20. Plutonium radiation surrogate

    DOEpatents

    Frank, Michael I. (Dublin, CA)

    2010-02-02

    A self-contained source of gamma-ray and neutron radiation suitable for use as a radiation surrogate for weapons-grade plutonium is described. The source generates a radiation spectrum similar to that of weapons-grade plutonium at 5% energy resolution between 59 and 2614 keV, but contains no special nuclear material and emits little .alpha.-particle radiation. The weapons-grade plutonium radiation surrogate also emits neutrons having fluxes commensurate with the gamma-radiation intensities employed.

  1. 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.

  2. Introduction to radiation transport

    SciTech Connect

    Olson, G.L.

    1998-12-31

    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.

  3. MoSI RECAPTURES Sheet Location Band Size R Season (e.g. 2009-10) Page # CODE SEX AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MoSI RECAPTURES Sheet Location Band Size R Season (e.g. 2009-10) Page # CODE SEX AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Recapture if you didn't look Predation P Dead D at that feather tract. DATE BANDER'S INITIALS CODE BAND NUMBER

  4. MoSI UNBANDED Sheet Location Band Size U Season (e.g. 2009-10) Page # CODE SEX AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP

    E-print Network

    DeSante, David F.

    MoSI UNBANDED Sheet Location Band Size U Season (e.g. 2009-10) Page # CODE SEX AGE HOW AGED AND HOW SEXED SKULL CL. PROT. BR. PATCH FAT BODY MLT FF MOLT FF WEAR MOLT LIMITS & PLUMAGE DISP Only use 'U P Dead D at that feather tract. DATE BANDER'S INITIALS CODE BAND NUMBER SPECIES NAME SPECIES ALPHA

  5. Radiation protection at synchrotron radiation facilities.

    PubMed

    Liu, J C; Vylet, V

    2001-01-01

    A synchrotron radiation (SR) facility typically consists of an injector, a storage ring, and SR beamlines. The latter two features are unique to SR facilities, when compared to other types of accelerator facilities. The SR facilities have the characteristics of low injection beam power, but high stored beam power. The storage ring is generally above ground with people occupying the experimental floor around a normally thin concrete ring wall. This paper addresses the radiation issues, in particular the shielding design, associated with the storage ring and SR beamlines. Normal and abnormal beam losses for injection and stored beams, as well as typical storage ring operation, are described. Ring shielding design for photons and neutrons from beam losses in the ring is discussed. Radiation safety issues and shielding design for SR beamlines, considering gas bremsstrahlung and synchrotron radiation, are reviewed. Radiation source terms and the methodologies for shielding calculations are presented. PMID:11843084

  6. Radiation Protection in Canada

    PubMed Central

    Williams, N.

    1965-01-01

    The main emphasis of a provincial radiation protection program is on ionizing radiation produced by machines, although assistance is given to the Federal Radiation Protection Division in its program relating to radioactive substances. The basis for the Saskatchewan program of radiation protection is the Radiological Health Act 1961. An important provision of the Act is annual registration of radiation equipment. The design of the registration form encourages a “do-it-yourself” radiation and electrical safety inspection. Installations are inspected every two years by a radiation health officer. Two hundred and twenty-one deficiencies were found during inspection of 224 items of radiation equipment, the commonest being failure to use personal film badges. Insufficient filtration of the beam, inadequate limitation of the beam, and unnecessary exposure of operators were other common faults. Physicians have a responsibility to weigh the potential advantages against the hazards when requesting radiographic or fluoroscopic procedures. PMID:14282164

  7. Radiation Protection Handbook

    NASA Technical Reports Server (NTRS)

    1972-01-01

    A handbook which sets forth the Kennedy Space Center radiation protection policy is presented. The book also covers administrative direction and guidance on organizational and procedural requirements of the program. Only ionizing radiation is covered.

  8. Radiation effects in space

    SciTech Connect

    Fry, R.J.M.

    1986-01-01

    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)

  9. Understanding Radiation: Overview

    MedlinePLUS

    ... Radiation Radiation that has enough energy to move atoms in a molecule around or cause them to ... enough energy to remove tightly bound electrons from atoms, thus creating ions. Health Effects Health effects are ...

  10. Radiation and Your Health

    MedlinePLUS

    ... air, airline travel, some medical procedures, computers, and nuclear weapons test fallout. Â Understanding Radiation Radiation, which exists ... Risk Assessment Project Fernald Dosimetry Reconstruction Project Hanford Nuclear Weapons Facility The Hanford Thyroid Disease Study HTDS Guide ...

  11. Environmental Radiation Exposures

    Cancer.gov

    DCEG is investigating cancer risks among populations exposed to radiation from environmental sources, such as nuclear reactor accidents and fallout from weapons testing.   Atomic Bomb Survivors Childhood Leukemia and Background Radiation Semipalatinsk

  12. 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 ...

  13. Cell Radiation Experiment System

    NASA Technical Reports Server (NTRS)

    Morrison, Dennis R.

    2010-01-01

    The cell radiation experiment system (CRES) is a perfused-cell culture apparatus, within which cells from humans or other animals can (1) be maintained in homeostasis while (2) being exposed to ionizing radiation during controlled intervals and (3) being monitored to determine the effects of radiation and the repair of radiation damage. The CRES can be used, for example, to determine effects of drug, radiation, and combined drug and radiation treatments on both normal and tumor cells. The CRES can also be used to analyze the effects of radiosensitive or radioprotectant drugs on cells subjected to radiation. The knowledge gained by use of the CRES is expected to contribute to the development of better cancer treatments and of better protection for astronauts, medical-equipment operators, and nuclear-power-plant workers, and others exposed frequently to ionizing radiation.

  14. Radiation-induced tumorigenesis.

    PubMed

    Kim, In-Gyu; Lee, Yun-Sil Lee

    2003-01-31

    During the past 2 decades, radiation tumorigenesis researchers have focused on cellular and molecular mechanisms. We reviewed some of these research fields, since they may specifically relate to the induction of cancer by ionizing radiation. First, radiation-mediated mutation was discussed. Then the initiating event in radiation carcinogenesis, as well as other genetic events that may be involved, is discussed in terms of the possible role of the activation of genes and the loss of cell-cycle checkpoints. PMID:12542985

  15. Dangers of Radiation Exposure

    NSDL National Science Digital Library

    2012-08-03

    This is a lesson about radiation and the various sources of radiation that a spacecraft may encounter in its journey. Learners will calculate their annual exposure to high-energy radiation, identify sources of high-energy radiation, and explain why the near-Mercury environment is a concern for the Mercury MESSENGER mission. This is lesson 2 of 4 in the high school track of a module, titled Staying Cool. Note: the student guide starts on p. 17 of the PDF.

  16. Spacecraft radiator systems

    NASA Technical Reports Server (NTRS)

    Anderson, Grant A. (Inventor)

    2012-01-01

    A spacecraft radiator system designed to provide structural support to the spacecraft. Structural support is provided by the geometric "crescent" form of the panels of the spacecraft radiator. This integration of radiator and structural support provides spacecraft with a semi-monocoque design.

  17. Radiation Research Program (RRP)

    Cancer.gov

    The RRP is responsible for NCI’s clinically-related extramural radiation research program. The RRP establishes priorities, allocates resources, and evaluates the effectiveness of such radiation research being conducted by NCI grantees. RRP staff represent the program at NCI management and scientific meetings and provide scientific support to leadership on matters related to radiation research.

  18. Radiation Exposure and Pregnancy

    MedlinePLUS

    ... based on extensive studies of women exposed to atomic-bomb radiation at Hiroshima and Nagasaki and those pregnant women who received x-ray studies, radionuclide medical tests, and other medical radiation ... International Atomic Energy Agency. Pregnancy and radiation protection in diagnostic ...

  19. JPL Radiation Effects Facilities

    NASA Technical Reports Server (NTRS)

    Thorbourn, Dennis

    2013-01-01

    Radiation Effects Group investigates the effects of space radiation on present and future microelectronic and optoelectronic technologies, evaluate the risk of using them in specific space missions, and recommend component and design techniques for JPL and NASA programs to reduce reliability risk from space radiation.

  20. Radiation Processing -an overview

    E-print Network

    1 Radiation Processing - an overview Arne Miller Risø High Dose Reference Laboratory Risø DTU DK of radiation · Facilities ­ Gamma ­ electrons ­ X-ray ­ Safety · Sterilisation of medical devices · Food ­ radiation hardness testing ­ semiconductors ­ microlitography ­ gem stones · Dosimetry · Quality assurance

  1. Radiation Damping with Inhomogeneous

    E-print Network

    Augustine, Mathew P.

    Radiation Damping with Inhomogeneous Broadening: Limitations of the Single Bloch Vector Model of inhomoge- neous broadening on radiation damping of free precession signals have been described using 13: 1 7, 2001 KEY WORDS: radiation damping; FID shape; inhomogeneous broadening The phenomenon

  2. astroph/9507030 Gravitational Radiation

    E-print Network

    Fygenson, Deborah Kuchnir

    astro­ph/9507030 10 Jul 95 Gravitational Radiation and Very Long Baseline Interferometry Ted Pyne of gravitational radiation on astrometric observations. We derive an equation for the time delay measured by two antennae observing the same source in an Einstein­de Sitter spacetime containing gravitational radiation

  3. Appendix G. Radiation Appendix G. Radiation G-3

    E-print Network

    Pennycook, Steve

    Appendix G. Radiation #12;#12;Appendix G. Radiation G-3 Appendix G. Radiation This appendix presents basic facts about radiation. The information is intended to be a basis for un- derstanding), not as a comprehensive discussion of radiation and its effects on the environment and biological systems. Radiation comes

  4. Appendix F. Radiation Appendix F. Radiation F-3

    E-print Network

    Pennycook, Steve

    Appendix F. Radiation #12;#12;Appendix F. Radiation F-3 Appendix F. Radiation This appendix presents basic facts about radiation. The information is intended to be a basis for un- derstanding), not as a comprehensive discussion of radiation and its effects on the environment and biological systems. Radiation comes

  5. Cumulative radiation damage and cumulative radiation effect.

    PubMed

    Väyrynen, T

    1983-01-01

    Different mathematical formulas capable of replacing CRE have been analyzed. The purpose was to develop an expression which would yield a value identical with CRE for regular treatment schedules, but would represent more clearly and more truthfully the radiation damage of tissue. This quantity has been called cumulative radiation damage (CRD). Its unit is adequately called CRD unit. CRD does not require a separate gap correction, as does CRE, it is easy to use, explicit and unambiguous. CRE, CRD and some other formulas have been compared in different types of radiation therapy. PMID:6316749

  6. Radiation Shielding and Radiological Protection

    E-print Network

    Shultis, J. Kenneth

    Radiation Shielding and Radiological Protection J. Kenneth Shultis Richard E. Faw Department@triad.rr.com Radiation Fields and Sources ................................................ . Radiation Field Variables........................................................... .. Direction and Solid Angle Conventions ......................................... .. Radiation Fluence

  7. Radiation Safety Program Annual Review

    E-print Network

    Lyubomirsky, Ilya

    .................................................................................................3 MANAGEMENT OVERSIGHT OF THE RADIATION SAFETY/LASER SAFETY PROGRAMS .............3 LICENSE RENEWAL SAFETY/LASER SAFETY PROGRAM OVERVIEW.......................................................4 RADIATION for Radiation Producing Machines (RPM) Expires 8/31/2011 MANAGEMENT OVERSIGHT OF THE RADIATION SAFETY/LASER

  8. Biomedical Uses of Radiation

    NASA Astrophysics Data System (ADS)

    Hendee, William R.

    1999-06-01

    The types of radiation routinely used for medical diagnosis and treatment ranges from different kinds of electromagnetic radiation (radio, infrared, ultraviolet, X-ray) to ultrasound. Keeping pace with all the different methods, their specific advantages and their hidden dangers is almost impossible. Written by experienced experts mainly from the US, this handbook provides a comprehensive overview over the principles, advantages and potential risks of all radiation-based methods commonly used. Volume A describes the acting mechanisms for different types of radiation, volume B focuses on their clinical applications, the information collected by each method and their potential risks. An indispensable reference work for (radiation) physicians, biophysicists and medical engineers.

  9. Nuclear Energy: Radiation Exposure

    NSDL National Science Digital Library

    John Pratte

    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.

  10. Mossbauer spectrometer radiation detector

    NASA Technical Reports Server (NTRS)

    Singh, J. J. (inventor)

    1973-01-01

    A Mossbauer spectrometer with high efficiencies in both transmission and backscattering techniques is described. The device contains a sodium iodide crystal for detecting radiation caused by the Mossbauer effect, and two photomultipliers to collect the radiation detected by the crystal. When used in the transmission technique, the sample or scatterer is placed between the incident radiation source and the detector. When used in a backscattering technique, the detector is placed between the incident radiation source and the sample of scatterer such that the incident radiation will pass through a hole in the crystal and strike the sample. Diagrams of the instrument are provided.

  11. Solar cell radiation handbook

    NASA Technical Reports Server (NTRS)

    Carter, J. R., Jr.; Tada, H. Y.

    1973-01-01

    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 used in the evaluation of radiation effects. Other topics discussed include: theoretical aspects of radiation damage, methods for developing relative damage coefficients, nature of the space radiation environment, method of calculating equivalent fluence from electron and proton energy spectrums and relative damage coefficients, and comparison of flight data with estimated degradation.

  12. Radiation protection in space

    SciTech Connect

    Blakely, E.A. [Lawrence Berkeley Lab., CA (United States); Fry, R.J.M. [Oak Ridge National Lab., TN (United States)

    1995-02-01

    The challenge for planning radiation protection in space is to estimate the risk of events of low probability after low levels of irradiation. This work has revealed many gaps in the present state of knowledge that require further study. Despite investigations of several irradiated populations, the atomic-bomb survivors remain the primary basis for estimating the risk of ionizing radiation. Compared to previous estimates, two new independent evaluations of available information indicate a significantly greater risk of stochastic effects of radiation (cancer and genetic effects) by about a factor of three for radiation workers. This paper presents a brief historical perspective of the international effort to assure radiation protection in space.

  13. Gas particle radiator

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L.

    1987-01-01

    The performance of a new space radiator concept, the gas particle radiator (GPR), is studied. The GPR uses a gas containing submicron particles as the radiating medium contained between the radiator's emitting surface and a transparent window. For a modest volume fraction of submicron particles and gas thickness, it is found that the emissivity is determined by the window transmittance. The window must have a high transmittance in the infrared and be structurally strong enough to contain the gas-particle mixture. When the GPR is compared to a proposed titanium wall, potassium heat pipe radiator, with both radiators operating at a power level of 1.01 MW at 775 K, it is found that the GPR mass is 31 percent lower than that of the heat pipe radiator.

  14. RF radiation from lightning

    NASA Technical Reports Server (NTRS)

    Levine, D. M.

    1978-01-01

    Radiation from lightning in the RF band from 3-300 MHz were monitored. Radiation in this frequency range is of interest as a potential vehicle for monitoring severe storms and for studying the lightning itself. Simultaneous measurements were made of RF radiation and fast and slow field changes. Continuous analogue recordings with a system having 300 kHz of bandwidth were made together with digital records of selected events (principally return strokes) at greater temporal resolution. The data reveal patterns in the RF radiation for the entire flash which are characteristic of flash type and independent of the frequency of observation. Individual events within the flash also have characteristic RF patterns. Strong radiation occurs during the first return strokes, but delayed about 20 micron sec with respect to the begining of the return stroke; whereas, RF radiation from subsequent return strokes tends to be associated with cloud processes preceding the flash with comparatively little radiation occurring during the return stroke itself.

  15. Americans' Average Radiation Exposure

    SciTech Connect

    NA

    2000-08-11

    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.

  16. High-power radiating plasma

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    The physical principles underlying the use of radiating plasmas for the optical pumping of lasers are described. Particular consideration is given to the properties of radiating plasmas; radiation selectivity; the dynamics, equilibrium, and stability of radiating plasmas; the radiative Reynolds number; and experimental results on radiating discharges.

  17. Radiation physics, biophysics, and radiation biology

    SciTech Connect

    Hall, E.J.; Zaider, M.

    1993-05-01

    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.

  18. Radiation exposure and pregnancy.

    PubMed

    Labant, Amy; Silva, Christina

    2014-01-01

    Radiological exposure from nuclear power reactor accidents, transportation of nuclear waste accidents, industrial accidents, or terrorist activity may be a remote possibility, but it could happen. Nurses must be prepared to evaluate and treat pregnant women and infants who have been exposed to radiation, and to have an understanding of the health consequences of a nuclear or radiological incident. Pregnant women and infants are a special group of patients who need consideration when exposed to radiation. Initial care requires thorough assessment and decisions regarding immediate care needs. Ongoing care is based on type and extent of radiation exposure. With accurate, comprehensive information and education, nurses will be better prepared to help mitigate the effects of radiation exposure to pregnant women and infants following a radiological incident. Information about radiation, health effects of prenatal radiation exposure, assessment, patient care, and treatment of pregnant women and infants are presented. PMID:25333800

  19. Jet radiation radius

    NASA Astrophysics Data System (ADS)

    Han, Zhenyu

    2014-10-01

    Jet radiation patterns are indispensable for the purpose of discriminating partons with different quantum numbers. However, they are also vulnerable to various contaminations from the underlying event, pileup, and radiation of adjacent jets. In order to maximize the discrimination power, it is essential to optimize the jet radius used when analyzing the radiation patterns. We introduce the concept of jet radiation radius, which quantifies how the jet radiation is distributed around the jet axis. We study the color and momentum dependence of the jet radiation radius and discuss two applications: quark-gluon discrimination and W -jet tagging. In both cases, smaller (sub)jet radii are preferred for jets with higher pT's, albeit due to different mechanisms: the running of the QCD coupling constant and the boost to a color-singlet system. A shrinking cone W -jet tagging algorithm is proposed to achieve better discrimination than previous methods.

  20. The flying radiation case

    SciTech Connect

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

    1997-04-01

    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.

  1. MULTIPOINT RADIATION MONITOR

    Microsoft Academic Search

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

    2006-01-01

    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

  2. Multipoint radiation monitor

    Microsoft Academic Search

    K. J. Hofstetter; D. M. Beals; D. M. Odell; R. F. Eakle; R. K. Huffman; L. J. Harpring

    2008-01-01

    A simple, inexpensive instrument for measuring radiation fields in otherwise inaccessible locations has been developed. The\\u000a RadRope consists of a series of radiation detectors inside a flexible sheath and connected to a data readout device to alert\\u000a the operator to unexpected radiation fields at a remote location. The instrument is designed for use in a maritime environment\\u000a and will assist

  3. Intracranial interstitial radiation

    SciTech Connect

    Willis, D.; Rittenmeyer, H.; Hitchon, P.

    1986-06-01

    Primary malignant brain tumors are fatal, with 90% of patients having these tumors dying within two years following diagnosis. Cranial interstitial radiation therapy, a technique under investigation to control these tumors, involves implantation of radioactive iodine 125 seeds into the tumor bed by stereotaxic technique. The interstitial radiation technique, monitoring of radiation, and nursing care of patients are discussed. Case histories are presented, along with discussion of results attained using this therapy, and its future.

  4. Radiation-induced ignition

    SciTech Connect

    Park, S.

    1989-01-01

    The effects of gas-phase radiation absorption on radiative ignition of various combustible materials under gravity conditions are studied. The physical models in this study range from a simple gas layer to a complex porous structure. Methyl methacrylate (MMA: C{sub 5}H{sub 8}O{sub 2}) vapor has been selected as a representative of participating gases in gas-phase radiation interactions. Its infrared radiation properties were measured using low-resolution spectral apparatus and then correlated in simple usable forms. As expected from its complex molecular structure, the infrared absorption capabilities of MMA vapor is much stronger than those of simpler hydrocarbon gases as well as water vapor and carbon dioxide. Radiation induced ignition was analyzed on the basis of simple theoretical models. Using Semenov's theory, results indicate a decrease in the critical surrounding temperature for a low Biot number system. For a high Biot number system, ignitability is defined through the use of Frank-Kamenetskii's critical parameter delta. One-dimensional transient models were developed for the analyses of radiation induced ignition of solid and porous solid fuels. The models include gas-phase radiation absorption, in-depth radiation interaction by the solid phase, Arrhenius-type chemical reaction, and natural convection. Predicted transmittance during ignition processes confirms the attenuation of incident radiation by pyrolyzed gases which has been already observed experimentally. An ignition process with gas-phase radiation absorption results in a quite different and widened ignition domain compared to that without gas-phase radiation absorption. Moreover, ignition is totally dependent on gas-phase radiation absorption under unfavorable conditions for a thermal runaway.

  5. RHOBOT: Radiation hardened robotics

    SciTech Connect

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

    1997-10-01

    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.

  6. Rotating bubble membrane radiator

    DOEpatents

    Webb, Brent J. (West Richland, WA); Coomes, Edmund P. (West Richland, WA)

    1988-12-06

    A heat radiator useful for expelling waste heat from a power generating system aboard a space vehicle is disclosed. Liquid to be cooled is passed to the interior of a rotating bubble membrane radiator, where it is sprayed into the interior of the bubble. Liquid impacting upon the interior surface of the bubble is cooled and the heat radiated from the outer surface of the membrane. Cooled liquid is collected by the action of centrifical force about the equator of the rotating membrane and returned to the power system. Details regarding a complete space power system employing the radiator are given.

  7. Radiation coloration resistant glass

    DOEpatents

    Tomozawa, Minoru (Troy, NY); Watson, E. Bruce (Troy, NY); Acocella, John (Troy, NY)

    1986-01-01

    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.

  8. Radiation view factor program

    NASA Technical Reports Server (NTRS)

    Lovin, J. K.; Lubkowitz, A. W.

    1971-01-01

    Computer program, RAVFAC, calculates diffuse radiation view factors, using contour integrals. Technique is combined with finite difference /double summation/ technique to compose total program package.

  9. Radiation coloration resistant glass

    DOEpatents

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

    1986-11-04

    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.

  10. Charms of radiation research.

    SciTech Connect

    Inokuti, M.; Physics

    2005-01-01

    Most of my professional efforts over nearly five decades have been devoted to radiation research, that is, studies of the physical, chemical, and biological actions of high-energy radiation on matter. (By the term 'high-energy radiation' I mean here x rays, .GAMMA. rays, neutrons, and charged particles of high enough energies to produce ionization in matter. I exclude visible light, infrared waves, microwaves, and sound waves.) Charms of radiation research lie in its interdisciplinary character; although my training was in basic physics, the scope of my interest has gradually increased to cover many other areas, to my deep satisfaction. High-energy radiation is an important component of the universe, and of our environment. It often provides an effective avenue for characterizing matter and understanding its behavior. Near Earth's surface this radiation is normally present in exceptionally low quantity, and yet it plays a significant role in some atmospheric phenomena such as auroras, and also in the evolution of life. The recent advent of various devices for producing high-energy radiation has opened up the possibility of many applications, including medical and industrial uses. I have worked on some aspects of those uses. At every opportunity to address a broad audience I try to convey a sense of intellectual fun, together with some of the elements of the basic science involved. A goal of radiation education might be to make the word 'radiation' as common and familiar as words such as 'fire' and 'electricity' through increased usage.

  11. Potential theory of radiation

    NASA Technical Reports Server (NTRS)

    Chiu, Huei-Huang

    1989-01-01

    A theoretical method is being developed by which the structure of a radiation field can be predicted by a radiation potential theory, similar to a classical potential theory. The introduction of a scalar potential is justified on the grounds that the spectral intensity vector is irrotational. The vector is also solenoidal in the limits of a radiation field in complete radiative equilibrium or in a vacuum. This method provides an exact, elliptic type equation that will upgrade the accuracy and the efficiency of the current CFD programs required for the prediction of radiation and flow fields. A number of interesting results emerge from the present study. First, a steady state radiation field exhibits an optically modulated inverse square law distribution character. Secondly, the unsteady radiation field is structured with two conjugate scalar potentials. Each is governed by a Klein-Gordon equation with a frictional force and a restoring force. This steady potential field structure and the propagation of radiation potentials are consistent with the well known results of classical electromagnetic theory. The extension of the radiation potential theory for spray combustion and hypersonic flow is also recommended.

  12. An Introduction to Radiation General Definition of Radiation

    E-print Network

    Massey, Thomas N.

    Module 1 An Introduction to Radiation #12;General Definition of Radiation · Ionizing radiation, for example, X-rays, gamma-rays, particles · Ionizing radiation is capable of removing an electron from the atom with which it interacts (ionization). · Non-ionizing radiation, for example, visible light

  13. Radiation physics, biophysics, and radiation biology

    SciTech Connect

    Hall, E.J.

    1992-05-01

    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.

  14. RADIATION ONCOLOGY TARGET YOUR FUTURE

    E-print Network

    Tobar, Michael

    RADIATION ONCOLOGY TARGET YOUR FUTURE #12;A Career in Radiation Oncology YOUR CHOICE SAVE LIVES Take the first step towards a career in Radiation Oncology Visit www.acareerinradiationoncology.com.au 2 What is Radiation Oncology? Radiation Oncology is made up of three unique medical specialties

  15. Microcircuit radiation effects databank

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Radiation test data submitted by many testers is collated to serve as a reference for engineers who are concerned with and have some knowledge of the effects of the natural radiation environment on microcircuits. Total dose damage information and single event upset cross sections, i.e., the probability of a soft error (bit flip) or of a hard error (latchup) are presented.

  16. Forecasting Radiation Fog

    NSDL National Science Digital Library

    2014-09-14

    This is the second module in the Mesoscale Meteorology Primer series. This module starts with a forecast scenario that occurs during a winter radiation fog event in the Central Valley of California. After that, a conceptual section covers the physical processes of radiation fog through its life cycle. Operational sections addressing fog detection and forecasting conclude the module

  17. Ultraviolet radiation changes

    NASA Technical Reports Server (NTRS)

    Mckenzie, Richard L.; Frederick, John E.; Ilyas, Mohammad; Filyushkin, V.; Wahner, Andreas; Stamnes, K.; Muthusubramanian, P.; Blumthaler, M.; Roy, Colin E.; Madronich, Sasha

    1991-01-01

    A major consequence of ozone depletion is an increase in solar ultraviolet (UV) radiation received at the Earth's surface. This chapter discusses advances that were made since the previous assessment (World Meteorological Organization (WMO)) to our understanding of UV radiation. The impacts of these changes in UV on the biosphere are not included, because they are discussed in the effects assessment.

  18. Radiation effects in space

    SciTech Connect

    Fry, R.J.M.

    1987-07-01

    As more people spend more time in space, and the return to the moon and exploratory missions are considered, the risks require continuing examination. The effects of microgravity and radiation are two potential risks in space. These risks increase with increasing mission duration. This document considers the risk of radiation effects in space workers and explorers. 17 refs., 1 fig., 4 tabs.

  19. RADIATION CHEMISTRY OF GASES

    Microsoft Academic Search

    1962-01-01

    Discussions are presented concerning the advantages and limitations of ; gas phase studies in radiation chemistry, observed effects of phase in radiation, ; hot reactions, reactions of thermal I atoms, HCl catalyzed chain isomerizations, ; molecular Hâ detachment, fragmentation of charged species, role of excited ; states, and dissociative electron attachment. (J.R.D.);

  20. Radiation-resistant microorganism

    DOEpatents

    Fliermans, Carl B.

    2010-06-15

    An isolated and purified bacterium is provided which was isolated from a high-level radioactive waste site of mixed waste. The isolate has the ability to degrade a wide variety of organic contaminants while demonstrating high tolerance to ionizing radiation. The organism is uniquely suited to bioremediation of a variety or organic contaminants while in the presence of ionizing radiation.

  1. Radiation detection system

    DOEpatents

    Franks, Larry A. (Santa Barbara, CA); Lutz, Stephen S. (Santa Barbara, CA); Lyons, Peter B. (Los Alamos, NM)

    1981-01-01

    A radiation detection system including a radiation-to-light converter and fiber optic wave guides to transmit the light to a remote location for processing. The system utilizes fluors particularly developed for use with optical fibers emitting at wavelengths greater than about 500 nm and having decay times less than about 10 ns.

  2. Treatment of Radiation Injury

    PubMed Central

    Akita, Sadanori

    2014-01-01

    Significance: Radiation exposure as a result of radiation treatment, accident, or terrorism may cause serious problems such as deficiency due to necrosis or loss of function, fibrosis, or intractable ulcers in the tissues and organs. When the skin, bone, oral mucous membrane, guts, or salivary glands are damaged by ionizing radiation, the management and treatment are very lengthy and difficult. Critical Issues: In severe and irreversible injuries, surgery remains the mainstay of treatment. Several surgical procedures, such as debridement, skin grafting, and local and free-vascularized flaps, are widely used. Recent Advances: In specific cases of major morbidity or in high-risk patients, a newly developed therapy using a patient's own stem cells is safe and effective. Adipose tissue, normally a rich source of mesenchymal stem cells, which are similar to those from the bone marrow, can be harvested, since the procedure is easy, and abundant tissue can be obtained with minimal invasiveness. Future Directions: Based on the molecular basis of radiation injuries, several prospective treatments are under development. Single-nucleotide polymorphisms focus on an individual's sensitivity to radiation in radiogenomics, and the pathology of radiation fibrosis or the effect of radiation on wound healing is being studied and will lead to new insight into the treatment of radiation injuries. Protectors and mitigators are being actively investigated in terms of the timing of administration or dose. PMID:24761339

  3. Radiation Exposure Compensation Program

    NSDL National Science Digital Library

    U.S. Department of Justice Radiation Exposure Compensation Program

    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.

  4. Radiation in the universe

    NASA Technical Reports Server (NTRS)

    Stuhlinger, Ernst; Truemper, Joachim; Weisskopf, Martin

    1992-01-01

    When Wilhelm Conrad Roentgen discovered radiation one hundred years ago, it seemed that what was discovered was one of the rarest and most volatile members of the family of the basic modules of our natural world. Today cosmologists report that a substantial part of the universe's radiation energy consists of X-rays, which travel through cosmic space with the speed of light.

  5. Synchrotron Radiation II.

    ERIC Educational Resources Information Center

    MOSAIC, 1978

    1978-01-01

    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)

  6. Thallium bromide radiation detectors

    Microsoft Academic Search

    K. S. Shah; J. C. Lund; F. Olschner; L. Moy; M. R. Squillante

    1989-01-01

    Radiation detectors have been fabricated from crystals of the semiconductor material thallium bromide (TlBr) and the performance of these detectors as room temperature photon spectrometers has been measured. These detectors exhibit improved energy resolution over previously reported TlBr detectors. These results indicate that TlBr is a very promising radiation detector material.

  7. Radiation based Marco Salerno

    E-print Network

    Sandini, Giulio

    , biology (cells, bacteria, virus, colloidal particles, ...) · geology (crystals, ...) · material science coherent oscillators (radiating antennas)(radiating antennas) Abbe eq.Abbe eq. 91 Airy function profile s #12;Why higher resolution? i.e. electrons ­ vs ­ photons "softer" diffraction limit DeBroglie = h / p

  8. GEWEX Radiative Flux Assessment

    Atmospheric Science Data Center

    2013-06-27

    GEWEX Radiative Flux Assessment The ultimate goal of the Global Energy and Water Cycle Experiment ( GEWEX ) global data analysis projects is to obtain observations of the ... (atmosphere, ocean, land, cryosphere, biosphere). The GEWEX Radiative Flux Assessment (RFA) project will provide a forum for ...

  9. Global radiation oncology waybill

    PubMed Central

    Muñoz-Garzón, Victor; Rovirosa, Ángeles; Ramos, Alfredo

    2013-01-01

    Background/aim Radiation oncology covers many different fields of knowledge and skills. Indeed, this medical specialty links physics, biology, research, and formation as well as surgical and clinical procedures and even rehabilitation and aesthetics. The current socio-economic situation and professional competences affect the development and future or this specialty. The aim of this article was to analyze and highlight the underlying pillars and foundations of radiation oncology, indicating the steps implicated in the future developments or competences of each. Methods This study has collected data from the literature and includes highlights from discussions carried out during the XVII Congress of the Spanish Society of Radiation Oncology (SEOR) held in Vigo in June, 2013. Most of the aspects and domains of radiation oncology were analyzed, achieving recommendations for the many skills and knowledge related to physics, biology, research, and formation as well as surgical and clinical procedures and even supportive care and management. Results Considering the data from the literature and the discussions of the XVII SEOR Meeting, the “waybill” for the forthcoming years has been described in this article including all the aspects related to the needs of radiation oncology. Conclusions Professional competences affect the development and future of this specialty. All the types of radio-modulation are competences of radiation oncologists. On the other hand, the pillars of Radiation Oncology are based on experience and research in every area of Radiation Oncology. PMID:24416572

  10. Physics for Radiation Protection

    NASA Astrophysics Data System (ADS)

    Martin, James E.

    2000-06-01

    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

  11. Radiation-resistant microorganism

    DOEpatents

    Fliermans, Carl B.

    2007-01-09

    An isolated and purified bacterium is provided which was isolated from a high-level radioactive waste site of mixed waste. The isolate has the ability to degrade a wide variety of organic contaminants while demonstrating high tolerance to ionizing radiation. The organism is uniquely suited to bioremediation of a variety or organic contaminants while in the presence of ionizing radiation.

  12. Chronic Radiation Enteritis

    Microsoft Academic Search

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

    2010-01-01

    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.

  13. RADIATION-CURABLE COATINGS

    EPA Science Inventory

    The report gives results of an evaluation of radiation-curable coatings as a technology for reducing volatile organic compound (VOC) emissions from surface coating operations. urvey of the literature was conducted to assess the state of the technology and emissions from radiation...

  14. Radiative Flux Analysis

    SciTech Connect

    Long, Chuck [NOAA

    2008-05-14

    The Radiative Flux Analysis is a technique for using surface broadband radiation measurements for detecting periods of clear (i.e. cloudless) skies, and using the detected clear-sky data to fit functions which are then used to produce continuous clear-sky estimates. The clear-sky estimates and measurements are then used in various ways to infer cloud macrophysical properties.

  15. Radiation-induced pneumothorax

    SciTech Connect

    Epstein, D.M.; Littman, P.; Gefter, W.B.; Miller, W.T.; Raney, R.B. Jr.

    1983-01-01

    Pneumothorax is an uncommon complication of radiation therapy to the chest. The proposed pathogenesis is radiation-induced fibrosis promoting subpleural bleb formation that ruptures resulting in pneumothorax. We report on two young patients with primary sarcomas without pulmonary metastases who developed spontaneous pneumothorax after irradiation. Neither patient had antecedent radiographic evidence of pulmonary fibrosis.

  16. Enhanced-Radiation Weapons

    Microsoft Academic Search

    Fred M. Kaplan

    1978-01-01

    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''

  17. Fundamentals of Radiation Dosimetry

    SciTech Connect

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

    2011-05-05

    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.

  18. Underwater radiation detector

    DOEpatents

    Kruse, Lyle W. (Albuquerque, NM); McKnight, Richard P. (Albuquerque, NM)

    1986-01-01

    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. Both the silver and lead foils allow the passage of gamma rays at a constant rate in a gamma ray only field. When neutrons are present, however, the silver activates and emits beta radiation that is also detected by the silver wrapped Geiger-Mueller tube while the radiation detected by the lead wrapped Geiger-Mueller tube remains constant. The amount of radiation impinging on the separate Geiger-Mueller tubes is then correlated in order to distinguish between the neutron and gamma radiations.

  19. Nuclear radiation actuated valve

    DOEpatents

    Christiansen, David W. (Kennewick, WA); Schively, Dixon P. (Richland, WA)

    1985-01-01

    A nuclear radiation actuated valve for a nuclear reactor. The valve has a valve first part (such as a valve rod with piston) and a valve second part (such as a valve tube surrounding the valve rod, with the valve tube having side slots surrounding the piston). Both valve parts have known nuclear radiation swelling characteristics. The valve's first part is positioned to receive nuclear radiation from the nuclear reactor's fuel region. The valve's second part is positioned so that its nuclear radiation induced swelling is different from that of the valve's first part. The valve's second part also is positioned so that the valve's first and second parts create a valve orifice which changes in size due to the different nuclear radiation caused swelling of the valve's first part compared to the valve's second part. The valve may be used in a nuclear reactor's core coolant system.

  20. Redirecting concentrated radiation

    NASA Astrophysics Data System (ADS)

    Collares-Pereira, Manuel; Mendes, Joao F.; Rabl, Ari; Ries, Harald

    1995-08-01

    Often the direction of radiation is important for technological reasons. Melting substances may drip down, or for air receivers, convection may cause instabilities. One obvious solution is to reorient the radiation before concentration with a planar mirror. This is only practical, if the angular spread is considerably less than 45 degrees. Here we propose a section of a torus with reflecting walls to reorient the radiation. The torus, by virtue of its rotational symmetry will not reject any radiation, even if the incoming radiation is close to the thermodynamic limit and thus completely diffuse. A toroid reflector can be easily manufactured from massive material and cooled. It seams a compact and practical device. We calculate the number of reflections and discuss applications of such a device in solar furnaces.

  1. Dangers of Radiation Exposure

    NSDL National Science Digital Library

    American Association for the Advancement of Science (AAAS; )

    2005-03-15

    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.

  2. Gravitational diffraction radiation

    E-print Network

    Vitor Cardoso; Marco Cavaglia; Mario Pimenta

    2006-10-04

    We show that if the visible universe is a membrane embedded in a higher-dimensional space, particles in uniform motion radiate gravitational waves because of spacetime lumpiness. This phenomenon is analogous to the electromagnetic diffraction radiation of a charge moving near to a metallic grating. In the gravitational case, the role of the metallic grating is played by the inhomogeneities of the extra-dimensional space, such as a hidden brane. We derive a general formula for gravitational diffraction radiation and apply it to a higher-dimensional scenario with flat compact extra dimensions. Gravitational diffraction radiation may carry away a significant portion of the particle's initial energy. This allows to set stringent limits on the scale of brane perturbations. Physical effects of gravitational diffraction radiation are briefly discussed.

  3. Broadband optical radiation detector

    NASA Technical Reports Server (NTRS)

    Gupta, A.; Hong, S. D.; Moacanin, J. (inventors)

    1981-01-01

    A method and apparatus for detecting optical radiation by optically monitoring temperature changes in a microvolume caused by absorption of the optical radiation to be detected is described. More specifically, a thermal lens forming material is provided which has first and second opposite, substantially parallel surfaces. A reflective coating is formed on the first surface, and a radiation absorbing coating is formed on the reflective coating. Chopped, incoming optical radiation to be detected is directed to irradiate a small portion of the radiation absorbing coating. Heat generated in this small area is conducted to the lens forming material through the reflective coating, thereby raising the temperature of a small portion of the lens forming material and causing a thermal lens to be formed therein.

  4. Solar radiation in Jamaica

    SciTech Connect

    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

    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.

  5. Deployable Heat Pipe Radiator

    NASA Technical Reports Server (NTRS)

    Edelstein, F.

    1975-01-01

    A 1.2- by 1.8-m variable conductance heat pipe radiator was designed, built, and tested. The radiator has deployment capability and can passively control Freon-21 fluid loop temperatures under varying loads and environments. It consists of six grooved variable conductance heat pipes attached to a 0.032-in. aluminum panel. Heat is supplied to the radiator via a fluid header or a single-fluid flexible heat pipe header. The heat pipe header is an artery design that has a flexible section capable of bending up to 90 degrees. Radiator loads as high as 850 watts were successfully tested. Over a load variation of 200 watts, the outlet temperature of the Freon-21 fluid varied by 7 F. An alternate control system was also investigated which used a variable conductance heat pipe header attached to the heat pipe radiator panel.

  6. Radiation Effects In Space

    SciTech Connect

    Tripathi, Ram K. [NASA Langley Research Center, MS - 188 E, Hampton VA 23681 (United States)

    2011-06-01

    Protecting space missions from severe exposures from radiation, in general, and long duration/deep space human missions, in particular, is a critical design driver, and could be a limiting factor. The space radiation environment consists of galactic cosmic rays (GCR), solar particle events (SPE), trapped radiation, and includes ions of all the known elements over a very broad energy range. These ions penetrate spacecraft materials producing nuclear fragments and secondary particles that damage biological tissues and microelectronic devices. One is required to know how every element (and all isotopes of each element) in the periodic table interacts and fragments on every other element in the same table as a function of kinetic energy ranging over many decades. In addition, the accuracy of the input information and database, in general and nuclear data in particular, impacts radiation exposure health assessments and payload penalty. After a brief review of effects of space radiation on materials and electronics, human space missions to Mars is discussed.

  7. Coherent curvature radiation

    NASA Astrophysics Data System (ADS)

    Kirk, J. G.

    1980-02-01

    With regard to coherent curvature radiation (CCR), calculations of the exact nature of the coherence requirements and the properties of the resulting radiation are reexamined. It is found that the general theory of CCR from plasma waves, as developed by Buscauer and Benford (1976), is correct only in the limit in which the plasma particles are stationary in the wave frame. In addition, features of their calculations, namely radiated energy which exceeds the product of the square of the number of particles times single particle radiation, as well as the feature of radiation at frequencies higher than the cutoff frequency for single particle emission, can be understood as spurious contributions originating in the boundary conditions.

  8. RADIATION BIOLOGY: CONCEPTS FOR RADIATION PROTECTION

    EPA Science Inventory

    ABSTRACT The opportunity to write a historical review of the field of radiation biology allows for the viewing of the development and maturity of a field of study, thereby being able to provide the appropriate context for the earlier years of research and its findings. The...

  9. Radiation therapy imaging apparatus

    SciTech Connect

    Chou, T.J.; Shoenfeld, H.; Greenway, W.C.

    1991-02-19

    This patent describes a radiation therapy imaging apparatus for providing images in a patient being treated on a radiation therapy apparatus for verification and monitoring of patient positioning and verification of alignment and shaping of the radiation field of the radiation therapy apparatus. It comprises: a high-energy treatment head for applying a radiation dose to a patient positioned on a treatment table, and a gantry rotatable about an isocentric axis and carrying the treatment head for permitting the radiation dose to be applied to the patient from any of a range of angles about the isocentric axis; the radiation therapy imaging apparatus including a radiation therapy image detector which comprises a video camera mounted on the gantry diametrically opposite the treat head, an elongated light-excluding enclosure enveloping the camera to exclude ambient light from the camera, a fluoroscopic plate positioned on a distal end of the enclosure remote from the camera and aligned with the head to produce a fluoroscopic image in response to radiation applied from the head through the patient, mirror means in the enclosure and oriented for reflecting the image to the camera to permit monitoring on a viewing screen of the position of the radiation field in respect to the patient, and means for retracting at least the distal end of the enclosure from a position in which the fluoroscopic plate is disposed opposite the treatment head without disturbing the position of the camera on the gantry, so that the enclosure can be collapsed and kept from projecting under the treatment table when the patient is being positioned on the treatment table.

  10. RADIATION SAFETY MANUAL POLICIES AND PROCEDURES

    E-print Network

    Zhang, Yuanlin

    RADIATION SAFETY MANUAL POLICIES AND PROCEDURES FOR RADIATION PROTECTION AT TEXAS TECH UNIVERSITY................................................................................................................I-1 B. Radiation Protection Program...............................................................................I-3 D. Radiation Safety Management

  11. COLUMBIA UNIVERSITY Radiation Safety Program

    E-print Network

    Jia, Songtao

    COLUMBIA UNIVERSITY Radiation Safety Program Medical Center - T: 212-305-0303 F: 212 Health & Safety www.ehs.columbia.edu Revised May 2011 Please Submit in Duplicate to: The Radiation Safety: ______________________________________________ Date: ______________ Radiation Safety Officer at Receiving Institution

  12. Radiation Therapy for Lung Cancer

    MedlinePLUS

    ... health. Radiation Therapy Radiation is a high-energy X-ray that can be used to treat lung cancer noninvasively. Radiation therapy works within cancer cells by damaging their ability to multiply. When these ...

  13. [Remote radiation planning support system].

    PubMed

    Atsumi, Kazushige; Nakamura, Katsumasa; Yoshidome, Satoshi; Shioyama, Yoshiyuki; Sasaki, Tomonari; Ohga, Saiji; Yoshitake, Tadamasa; Shinoto, Makoto; Asai, Kaori; Sakamoto, Katsumi; Hirakawa, Masakazu; Honda, Hiroshi

    2012-08-01

    We constructed a remote radiation planning support system between Kyushu University Hospital (KUH) in Fukuoka and Kyushu University Beppu Hospital (KBH) in Oita. Between two institutions, radiology information system for radiotherapy division (RT-RIS) and radiation planning system (RTPS) were connected by virtual private network (VPN). This system enables the radiation oncologists at KUH to perform radiotherapy planning for the patients at KBH. The detail of the remote radiation planning support system in our institutions is as follows: The radiation oncologist at KBH performs radiotherapy planning and the data of the patients are sent anonymously to the radiation oncologists at KUH. The radiation oncologists at KUH receive the patient's data, access to RTPS at KBH, verify or change the radiation planning at KBH: Radiation therapy is performed at KBH according to the confirmed plan by the radiation oncologists at KUH. Our remote radiation planning system is useful for providing radiation therapy with safety and accuracy. PMID:23157128

  14. Radiation for Students and Teachers

    MedlinePLUS

    ... Technical Information Understanding Radiation Learn about why some atoms give off radiation, the different kinds of radiation, ... same name. The guide includes units on: Modeling Atoms, Making Atoms Visible, Personal Dose, Irradiation and Benefits, ...

  15. Radiation Therapy for Testicular Cancer

    MedlinePLUS

    ... chemo and stem cell transplant for testicular cancer Radiation therapy for testicular cancer Radiation therapy uses high-energy rays or particles to ... cells or slow their growth. In testicular cancer, radiation is mainly used to kill cancer cells that ...

  16. 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 ...

  17. Radiation Safety (Revised March 2010)

    E-print Network

    Kay, Mark A.

    Radiation Safety Manual (Revised March 2010) Updated December 2012 Stanford University, Stanford California #12; #12; Radiation Safety Manual (Revised March 2010) Updated Environmental Health and Safety, Stanford University, Stanford California #12; CREDITS This Radiation Safety

  18. [Basis of radiation protection].

    PubMed

    Roth, J; Schweizer, P; Gückel, C

    1996-06-29

    After an introduction, three selected contributions to the 10th Course on Radiation Protection held at the University Hospital of Basel are presented. The principles of radiation protection and new Swiss legislation are discussed as the basis for radiological protection. Ways are proposed of reducing radiation exposure while optimizing the X-ray picture with a minimum dose to patient and personnel. Radiation effects from low doses. From the beginning, life on this planet has been exposed to ionizing radiation from natural sources. For about one century additional irradiation has reached us from man-made sources as well. In Switzerland the overall annual radiation exposure from ambient and man-made sources amounts to about 4 mSv. The terrestrial and cosmic radiation and natural radionuclids in the body cause about 1.17 mSv (29%). As much as 1.6 mSv (40%) results from exposure to radon and its progenies, primarily inside homes. Medical applications contribute approximately 1 mSv (26%) to the annual radiation exposure and releases from atomic weapons, nuclear facilities and miscellaneous industrial operations yield less than 0.12 mSv (< 5%) to the annual dose. Observations of detrimental radiation effects from intermediate to high doses are challenged by observations of biopositive adaptive responses and hormesis following low dose exposure. The important question, whether cellular adaptive response or hormesis could cause beneficial effects to the human organism that would outweigh the detrimental effects attributed to low radiation doses, remains to be resolved. Whether radiation exerts a detrimental, inhibitory, modifying or even beneficial effect is likely to result from identical molecular lesions but to depend upon their quantity, localization and time scale of initiation, as well as the specific responsiveness of the cellular systems involved. For matters of radiation protection the bionegative radiation effects are classified as deterministic effects or stochastic effects respectively. The various histopathological reactions of tissues and organs following localized tissue irradiation, and the radiation syndromes following total body irradiation, constitute the deterministic effects. There will be a threshold below which deterministic effects do not appear and spontaneous incidences are not known. For low dose risk considerations deterministic effects are of no significance. Genetic effects and carcinogenesis are said to be stochastic effects. Characteristically the probability of stochastic effects increases with dose but the severity of the effects is independent of the dose. The shape of the dose-response relationship at intermediate to high dose levels is linear-quadratic. For exposure to low doses the response becomes linear, as is to be expected for a linear-quadratic function at low dose. No threshold is assumed for stochastic effects. The estimate of probability of fatal cancer by the ICRP is 4 x 10(-2) per Sv for the working population and 5 x 10(-2) per Sv for the total population. Their estimate of probability of serious hereditary disorders within the first two generations is 1 x 10(-2) per Sv. The highest probability coefficient is attributed to mental retardation following exposure in utero. Within the sensitive period at 8-15 weeks of gestation, a risk probability of 40 x 10(-2) per Sv is assumed but a threshold at 0.1 Sv is not excluded. Conclusions drawn from experiments, clinical observations and epidemiological studies following intermediate to high radiation exposures attribute a mutagenic and carcinogenic competence to all radiation doses. Microdosimetric considerations support this assumption. This conclusion cannot be confirmed experimentally nor by epidemiological studies of populations living under different conditions from natural sources of radiation. Nevertheless, a change in the present restrictive radiation protection policy does not yet appear appropriate. PMID:8711464

  19. Modifying Radiation Damage

    PubMed Central

    Kim, Kwanghee; McBride, William H.

    2011-01-01

    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

  20. Radiation-induced enteropathy

    SciTech Connect

    Sher, M.E.; Bauer, J. (Mount Sinai Hospital, New York, NY (USA))

    1990-02-01

    The incidence of chronic radiation enteritis appears to have risen in recent years due to the increasing utilization of radiotherapy for abdominal and pelvic malignancies. The etiology, pathogenesis, and management of radiation enteritis are discussed. Two case reports exemplify the progressive nature of the disease. Case 1 demonstrates the classical picture of multiple exacerbations and remissions of partial small bowel obstruction and the eventual need for surgical management ten years after radiation therapy. Case 2 presents the more severe sequelae of an acute perforation with a 14-yr latency period. Predisposing factors in the progression of radiation injury include excessive radiation, underlying cardiovascular disease, fixation of the bowel, and an asthenic habitus. In both cases, radiation injury was localized to a discrete segment of bowel; therefore, resection with a primary end-to-end anastomosis was performed. In addition, diseased bowel was eliminated and, therefore, would not cause further complications such as intractable bleeding or fistula formation. The review focuses on current knowledge which may be applied to the treatment and prevention of radiation enteritis.

  1. Beneficial uses of radiation

    SciTech Connect

    Fox, M.R.

    1991-10-01

    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.

  2. Hoja de Recapturas MoSI Localidad Tamao de anillo R Temporada (p.ej 2009-10) Pgina # CODE SEXO EDAD COMO DETERMINAR LA EDAD Y EL SEXO CRNEO PROT. CLOAC. PARCH. DE INC. GRASA MUDA CUERP. MUDA PL. VUEL. DESGAS. VUEL. LIM. DE MUDA Y PL. TENDENCIA

    E-print Network

    DeSante, David F.

    Hoja de Recapturas MoSI Localidad Tamaño de anillo R Temporada (p.ej 2009-10) Página # CODE SEXO EDAD COMO DETERMINAR LA EDAD Y EL SEXO CRÁNEO PROT. CLOAC. PARCH. DE INC. GRASA MUDA CUERP. MUDA PL SEXO Lesión vieja, cicatrizad. Herida o enfermedad PARCH.DEINC. GRASA MUDACUERPO MUDAPL.VUEL. ANILLOS

  3. Hoja de Anillamiento MoSI Localidad Tamao de anillo Temporada (p.ej. 2009-10) Pgina # CDIGO SEXO EDAD COMO DETERMINAR LA EDAD Y EL SEXO CRNEO PROT. CLOAC. PARCH. DE INC. GRASA MUDA CUERP. MUDA PL. VUEL. DESGAS. VUEL. LIM. DE MUDA Y PL. TENDENCIA

    E-print Network

    DeSante, David F.

    Hoja de Anillamiento MoSI Localidad Tamaño de anillo Temporada (p.ej. 2009-10) Página # C�DIGO SEXO EDAD COMO DETERMINAR LA EDAD Y EL SEXO CRÁNEO PROT. CLOAC. PARCH. DE INC. GRASA MUDA CUERP. MUDA PL SEXO COMODET. ELSEXO Lesión vieja, cicatrizad. Herida o enfermedad MUDAPL.VUEL. DESGAS.VUEL. PLUMAJEJUV

  4. Stimulated coherent transition radiation

    SciTech Connect

    Hung-chi Lihn

    1996-03-01

    Coherent radiation emitted from a relativistic electron bunch consists of wavelengths longer than or comparable to the bunch length. The intensity of this radiation out-numbers that of its incoherent counterpart, which extends to wavelengths shorter than the bunch length, by a factor equal to the number of electrons in the bunch. In typical accelerators, this factor is about 8 to 11 orders of magnitude. The spectrum of the coherent radiation is determined by the Fourier transform of the electron bunch distribution and, therefore, contains information of the bunch distribution. Coherent transition radiation emitted from subpicosecond electron bunches at the Stanford SUNSHINE facility is observed in the far-infrared regime through a room-temperature pyroelectric bolometer and characterized through the electron bunch-length study. To measure the bunch length, a new frequency-resolved subpicosecond bunch-length measuring system is developed. This system uses a far-infrared Michelson interferometer to measure the spectrum of coherent transition radiation through optical autocorrelation with resolution far better than existing time-resolved methods. Hence, the radiation spectrum and the bunch length are deduced from the autocorrelation measurement. To study the stimulation of coherent transition radiation, a special cavity named BRAICER is invented. Far-infrared light pulses of coherent transition radiation emitted from electron bunches are delayed and circulated in the cavity to coincide with subsequent incoming electron bunches. This coincidence of light pulses with electron bunches enables the light to do work on electrons, and thus stimulates more radiated energy. The possibilities of extending the bunch-length measuring system to measure the three-dimensional bunch distribution and making the BRAICER cavity a broadband, high-intensity, coherent, far-infrared light source are also discussed.

  5. SYNCHROTRON RADIATION SOURCES

    SciTech Connect

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

    1998-07-01

    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.

  6. Synchrotron radiation sources and research

    SciTech Connect

    Teng, L.C.

    1995-12-31

    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.

  7. Microcircuit radiation effects databank

    NASA Technical Reports Server (NTRS)

    1983-01-01

    This databank is the collation of radiation test data submitted by many testers and serves as a reference for engineers who are concerned with and have some knowledge of the effects of the natural radiation environment on microcircuits. It contains radiation sensitivity results from ground tests and is divided into two sections. Section A lists total dose damage information, and section B lists single event upset cross sections, I.E., the probability of a soft error (bit flip) or of a hard error (latchup).

  8. Atmospheric Radiative Transfer

    Microsoft Academic Search

    Bruno Sportisse

    The interaction between atmospheric matter and solar and terrestrial radiation plays a leading role for life conditions at\\u000a the Earth’s surface: \\u000a \\u000a \\u000a \\u000a • \\u000a \\u000a stratospheric ozone filters the solar ultraviolet radiation;\\u000a \\u000a \\u000a • \\u000a \\u000a the absorption by a few gas-phase species (e.g. water, methane or carbon dioxide) of the terrestrial radiation defines the\\u000a so-called greenhouse effect, which results in a surface temperature greater than

  9. Radiation and Health

    NASA Astrophysics Data System (ADS)

    Evans, Albert; Blanchard, Karen

    2007-10-01

    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.

  10. Radiation and Health

    NASA Astrophysics Data System (ADS)

    Evans, Albert E.

    2008-03-01

    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.

  11. Radiation Safety System

    SciTech Connect

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

    2012-04-04

    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.

  12. Radiation safety system.

    PubMed

    Vylet, Vaclav; Liu, James C; Walker, Lawrence S

    2009-11-01

    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. PMID:19783555

  13. Composition for radiation shielding

    DOEpatents

    Kronberg, James W. (Aiken, SC)

    1994-01-01

    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.

  14. Synchrotron-radiation laser

    NASA Astrophysics Data System (ADS)

    Hirshfield, J. L.

    1992-02-01

    A formulation to characterize stimulated emission of synchrotron radiation is presented, based on simplification of a theory developed by Sokolov and Ternov. It is shown that optical gain may be obtained up to gyration harmonics of the order of the critical harmonic number for spontaneous radiation, 3 gamma-cubed, where gamma is the relativistic energy factor. Synchrotron-radiation lasers (SRLs) in the infrared and visible portions of the spectrum are shown to be feasible, provided beams with high energy definition are used. SRL gain can exceed free-electron-laser gain for similar beams.

  15. Space radiation studies

    NASA Technical Reports Server (NTRS)

    Gregory, J. C.

    1986-01-01

    Instrument design and data analysis expertise was provided in support of several space radiation monitoring programs. The Verification of Flight Instrumentation (VFI) program at NASA included both the Active Radiation Detector (ARD) and the Nuclear Radiation Monitor (NRM). Design, partial fabrication, calibration and partial data analysis capability to the ARD program was provided, as well as detector head design and fabrication, software development and partial data analysis capability to the NRM program. The ARD flew on Spacelab-1 in 1983, performed flawlessly and was returned to MSFC after flight with unchanged calibration factors. The NRM, flown on Spacelab-2 in 1985, also performed without fault, not only recording the ambient gamma ray background on the Spacelab, but also recording radiation events of astrophysical significance.

  16. Microwave Radiation Detector

    NASA Technical Reports Server (NTRS)

    Lesh, J. R.

    1984-01-01

    Direct photon detector responds to microwave frequencies. Method based on trapped-ion frequency-generation standards proposed to detect radio-frequency (RF) radiation at 40.5 GHz. Technique used for directdetection (RF) communication, radar, and radio astronomy.

  17. Amorphous silicon radiation detectors

    DOEpatents

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

    1992-11-17

    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.

  18. Amorphous silicon radiation detectors

    DOEpatents

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

    1992-01-01

    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.

  19. Management of radiation wounds

    SciTech Connect

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

    1984-08-01

    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.

  20. Portal radiation monitor

    DOEpatents

    Kruse, Lyle W. (Albuquerque, NM)

    1985-01-01

    A portal radiation monitor combines 0.1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.

  1. 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...

  2. Radiation in Microgravity

    NASA Technical Reports Server (NTRS)

    Nelson, G. A.

    1994-01-01

    Spaceflight results in unavoidable exposure of astronauts or experimental organisms to the complex space radiation environment while simultaneously subjecting the individuals to gravity unloading and other stresses such as vibroacoustic stimuli.

  3. Radiation-Induced Bioradicals

    NASA Astrophysics Data System (ADS)

    Lahorte, Philippe; Mondelaers, Wim

    This chapter represents the second part of a review in which the production and application of radiation-induced radicals in biological matter are discussed. In part one the general aspects of the four stages (physical, physicochemical, chemical and biological) of interaction of radiation with matter in general and biological matter in particular, were discussed. Here an overview is presented of modem technologies and theoretical methods available for studying these radiation effects. The relevance is highlighted of electron paramagnetic resonance spectroscopy and quantum chemical calculations with respect to obtaining structural information on bioradicals, and a survey is given of the research studies in this field. We also discuss some basic aspects of modem accelerator technologies which can be used for creating radicals and we conclude with an overview of applications of radiation processing in biology and related fields such as biomedical and environmental engineering, food technology, medicine and pharmacy.

  4. The Space Radiation Environment

    NASA Technical Reports Server (NTRS)

    Bourdarie, Sebastien; Xapsos, Michael A.

    2008-01-01

    The effects of the space radiation environment on spacecraft systems and instruments are significant design considerations for space missions. Astronaut exposure is a serious concern for manned missions. In order to meet these challenges and have reliable, cost-effective designs, the radiation environment must be understood and accurately modeled. The nature of the environment varies greatly between low earth orbits, higher earth orbits and interplanetary space. There are both short-term and long-term variations with the phase of the solar cycle. In this paper we concentrate mainly on charged particle radiations. Descriptions of the radiation belts and particles of solar and cosmic origin are reviewed. An overview of the traditional models is presented accompanied by their application areas and limitations. This is followed by discussion of some recent model developments.

  5. [Genetic effects of radiation].

    PubMed

    Nakamura, Nori

    2012-03-01

    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

  6. Radiation Therapy for Cancer

    MedlinePLUS

    ... including physicists and dosimetrists ) use sophisticated computers to design the details of the exact radiation plan that ... to travel. The patient’s general health and medical history. Whether the patient will have other types of ...

  7. Rhabdomyosarcoma: Radiation Therapy

    MedlinePLUS

    ... techniques, such as stereotactic radiotherapy and proton beam radiotherapy, are discussed briefly in the section “ What’s new in rhabdomyosarcoma research and treatment? ” Possible side effects The side effects of radiation therapy depend on ...

  8. Portal radiation monitor

    DOEpatents

    Kruse, L.W.

    1982-03-23

    A portal radiation monitor combines .1% FAR with high sensitivity to special nuclear material. The monitor utilizes pulse shape discrimination, dynamic compression of the photomultiplier output and scintillators sized to maintain efficiency over the entire portal area.

  9. Nuclear radiation detectors

    Microsoft Academic Search

    Luiz Alexandre Schuch; Daniel Jean Roger Nordemann

    1990-01-01

    Detectors of nuclear radiation, such as gaseous detectors, scintillators, and semiconductors, are presented through their general properties and with their operating systems. The semiconductor detectors are studied with more details.

  10. STANFORD SYNCHROTRON RADIATION LIGHTSOURCE

    E-print Network

    Kay, Mark A.

    in energy production, environmental remediation, nanotechnology, new materials and medicine. SSRL also, new types of solar cells, more powerful electronics, catalysts that speed chemical reactions, and novel computing technologies. The Stanford Synchrotron Radiation Lightsource is an Office of Science

  11. Tin Can Radiation Detector.

    ERIC Educational Resources Information Center

    Crull, John L.

    1986-01-01

    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)

  12. Radiation Tolerant Antifuse FPGA

    NASA Technical Reports Server (NTRS)

    Wang, Jih-Jong; Cronquist, Brian; McCollum, John; Parker, Wanida; Katz, Rich; Kleyner, Igor; Day, John H. (Technical Monitor)

    2002-01-01

    The total dose performance of the antifuse FPGA for space applications is summarized. Optimization of the radiation tolerance in the fabless model is the main theme. Mechanisms to explain the variation in different products are discussed.

  13. External Radiation Therapy

    MedlinePLUS Videos and Cool Tools

    Narrator: When the cancer is not completely contained in the prostate or when the patient is older the treatment that is frequently used ... There are different forms of radiation for prostate cancer. They really boil down to two different types. ...

  14. Ionizing radiation detector

    DOEpatents

    Thacker, Louis H. (Knoxville, TN)

    1990-01-01

    An ionizing radiation detector is provided which is based on the principle 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.

  15. Radiation Dose Chart

    NSDL National Science Digital Library

    Randall Munroe

    This is an illustration of the ionizing radiation dose a person can absorb from various sources. It provides a visual comparison of doses ranging from 0.1 microsieverts (from eating a banana) to a fatal dose of 8 sieverts.

  16. Occupational Radiation Exposures

    Cancer.gov

    DCEG researchers are studying cancer risks among populations who are occupationally exposed to radiation. Chernobyl Clean-up Workers Mayak Nuclear Facility Workers U.S. Radiologic Technologists Interventional Fluoroscopists Print This Page Occupational

  17. Method of enhancing radiation response of radiation detection materials

    DOEpatents

    Miller, Steven D. (Richland, WA)

    1997-01-01

    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.

  18. Method of enhancing radiation response of radiation detection materials

    Microsoft Academic Search

    Steven D

    1997-01-01

    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 \\

  19. Radiation Safety Manual Dec 2012 Page 1 RADIATION SAFETY

    E-print Network

    Grishok, Alla

    Radiation Safety Manual ­ Dec 2012 Page 1 RADIATION SAFETY MANUAL For Columbia University NewYork-Presbyterian Hospital New York State Psychiatric Institute Barnard College December 2012 #12;Radiation Safety Manual ­ Dec 2012 Page 1 Table of Contents Introduction Chapter I: Radiation Safety Program A. Program

  20. Radiation Safety Training Basic Radiation Safety Training for

    E-print Network

    Dai, Pengcheng

    Radiation Safety Training Basic Radiation Safety Training for X-ray Users for Physics 461 & 462 Modern Physics Laboratory Spring 2007 #12;#12;Radiation Safety Department, University of Tennessee Protocol Title: Basic Radiation Safety Training for X-ray Users Drafted By: Chris Millsaps, RSS Reviewers

  1. The NCI Radiation Research Program: Grant portfolio and radiation

    E-print Network

    The NCI Radiation Research Program: Grant portfolio and radiation dosimetry as applied and R37s). Of those that utilize radiation: · 6 use tissue culture models only · 110 utilize animal radiation (excepting those with human subjects or physics grants) mention dosimetry in the proposals (4

  2. Radiation Safety Training Basic Radiation Safety Training for

    E-print Network

    Dai, Pengcheng

    Radiation Safety Training Basic Radiation Safety Training for Sealed Source Users for Physics 461 & 462 Modern Physics Laboratory Spring 2007 #12;Radiation Safety Department, University of Tennessee Purpose: To provide basic radiation safety training to the users of sealed sources located

  3. Auditing radiation sterilization facilities

    NASA Astrophysics Data System (ADS)

    Beck, Jeffrey A.

    The diversity of radiation sterilization systems available today places renewed emphasis on the need for thorough Quality Assurance audits of these facilities. Evaluating compliance with Good Manufacturing Practices is an obvious requirement, but an effective audit must also evaluate installation and performance qualification programs (validation_, and process control and monitoring procedures in detail. The present paper describes general standards that radiation sterilization operations should meet in each of these key areas, and provides basic guidance for conducting QA audits of these facilities.

  4. Liquid sheet radiator apparatus

    NASA Technical Reports Server (NTRS)

    Chubb, Donald L. (inventor)

    1990-01-01

    An external flow, liquid sheet radiator apparatus adapted for space applications has as its radiating surface a thin stable liquid sheet formed by fluid flow through a very narrow slit affixed to the sheet generator. As a result of surface tension forces, the sheet has a triangular shape and is collected into a simply designed collector positioned at the apex of the triangle. The specific power for the liquid sheet is virtually the same as the droplet sheet specific power.

  5. Radiation-induced sarcoma

    Microsoft Academic Search

    Shreyaskumar R. Patel

    2000-01-01

    Opinion statement  Radiation-induced sarcomas can originate in either the irradiated bone or soft tissues. Most of these tumors are high-grade.\\u000a The most common histologic subtypes are malignant fibrous histiocytoma (MFH) and osteosarcoma, although other histologies\\u000a (eg, angiosarcoma, rhabdomyosarcoma) can occur. Tumor size and grade are the two most important prognostic factors for soft tissue\\u000a sarcomas, including those associated with radiation therapy.

  6. [Radiation protection in radiation oncology. Yesterday, today, and tomorrow].

    PubMed

    Herrmann, Th; Müller, R

    2012-11-01

    Publications about radiation protection issues are not very frequent in the 100-year-old history of Strahlentherapie und Onkologie. While at the beginning of the last century the problems of radiation protection were determined by the technical development of radiation therapy, the importance of radiation protection measures and knowledge about radiation protection by the persons involved has clearly increased. A new challenge is treating patients according to radiation safety issues to avoid the risk of stochastic late effects, such as radiation-induced secondary tumors. PMID:22907582

  7. ISO radiation sterilization standards

    NASA Astrophysics Data System (ADS)

    Lambert, Byron J.; Hansen, Joyce M.

    1998-06-01

    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" li]4. ISO Draft TR, "Sterilization of health care products — Radiation sterilization-Product Families, Plans for Sampling and Frequency of Dose Audits."

  8. Packet personal radiation monitor

    DOEpatents

    Phelps, James E. (Knoxville, TN)

    1989-01-01

    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 low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiation events, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible "chirp". The rate of the "chirps" is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field.

  9. Fabric space radiators

    SciTech Connect

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

    1988-01-01

    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.

  10. Gravitational Tunneling Radiation

    E-print Network

    Mario Rabinowitz

    2002-12-11

    The isolated black hole radiation of both Hawking and Zel'dovich are idealized abstractions as there is always another body to distort the potential. This is considered with respect to both gravitational tunneling, and black hole "no-hair" theorems. The effects of a second body are to lower the gravitational barrier of a black hole and to give the barrier a finite rather than infinite width so tha a particle can escape by tunneling (as in field emission) or over the top of the lowered barrier (as in Schottky emission). Thus radiation may be emitted from black holes in a process differing from that of Hawking radiation, P SH, which has been undetected for over 24 years. The radiated power from a black hole derived here is PR e ^2__ PSH, where e ^2__ is he ransmission probability for radiation through the barrier. This is similar to electric field emission of electrons from a metal in that the emission can in principle be modulated and beamed. The temperature and entropy of black holes are reexamined. Miniscule black holes herein may help explain the missing mass of the universe, accelerated expansion of the universe, and anomalous rotation of spiral galaxies. A gravitational interference effect for black hole radiation similar to the Aharonov-Bohm effect is also examined.

  11. Radiation analysis devices, radiation analysis methods, and articles of manufacture

    DOEpatents

    Roybal, Lyle Gene

    2010-06-08

    Radiation analysis devices include circuitry configured to determine respective radiation count data for a plurality of sections of an area of interest and combine the radiation count data of individual of sections to determine whether a selected radioactive material is present in the area of interest. An amount of the radiation count data for an individual section is insufficient to determine whether the selected radioactive material is present in the individual section. An article of manufacture includes media comprising programming configured to cause processing circuitry to perform processing comprising determining one or more correction factors based on a calibration of a radiation analysis device, measuring radiation received by the radiation analysis device using the one or more correction factors, and presenting information relating to an amount of radiation measured by the radiation analysis device having one of a plurality of specified radiation energy levels of a range of interest.

  12. Radiation Sensitization in Cancer Therapy.

    ERIC Educational Resources Information Center

    Greenstock, Clive L.

    1981-01-01

    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,…

  13. The Radiation Chemistry Data Center

    NSDL National Science Digital Library

    Madden, K.P.

    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.

  14. The Gilbert Beebe Radiation Fellowship

    Cancer.gov

    Description of the Gilbert Beebe Radiation Fellowship for mid- to senior-level epidemiologists or biostatisticians. Recipients work in the Radiation Epidemiology Branch of the National Cancer Institute and the Radiation Effects Research Foundation (RERF) in Hiroshima, Japan on research related to the atomic bomb survivors and other radiation topics.

  15. ADAPTIVE RADIATION ROSEMARY G. GILLESPIE

    E-print Network

    Gillespie, Rosemary

    1 A ADAPTIVE RADIATION ROSEMARY G. GILLESPIE University of California, Berkeley Adaptive radiation- tions and convergence of species groups on different land masses. Since then, adaptive radiation has diversity within a rapidly multiplying lineage." There are radiations that are not adaptive

  16. Bile Duct (Cholangiocarcinoma) Cancer: Radiation Therapy

    MedlinePLUS

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

  17. Radiation health research, 1986 - 1990

    NASA Technical Reports Server (NTRS)

    1991-01-01

    A collection of 225 abstracts of radiation research sponsored by NASA during the period 1986 through 1990 is reported. Each abstract was categorized within one of four discipline areas: physics, biology, risk assessment, and microgravity. Topic areas within each discipline were assigned as follows: Physics - atomic physics, nuclear science, space radiation, radiation transport and shielding, and instrumentation; Biology - molecular biology, cellular radiation biology, tissue, organs and organisms, radioprotectants, and plants; Risk assessment - radiation health and epidemiology, space flight radiation health physics, inter- and intraspecies extrapolation, and radiation limits and standards; and Microgravity. When applicable subareas were assigned for selected topic areas. Keywords and author indices are provided.

  18. Radiation in Particle Simulations

    SciTech Connect

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

    2010-11-19

    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.

  19. Radiation delivery system and method

    DOEpatents

    Sorensen, Scott A. (Overland Park, KS); Robison, Thomas W. (Los Alamos, NM); Taylor, Craig M. V. (Jemez Springs, NM)

    2002-01-01

    A radiation delivery system and method are described. The system includes a treatment configuration such as a stent, balloon catheter, wire, ribbon, or the like, a portion of which is covered with a gold layer. Chemisorbed to the gold layer is a radiation-emitting self-assembled monolayer or a radiation-emitting polymer. The radiation delivery system is compatible with medical catheter-based technologies to provide a therapeutic dose of radiation to a lesion following an angioplasty procedure.

  20. Remote radiation dosimetry

    DOEpatents

    Braunlich, Peter F. (Pullman, WA); Tetzlaff, Wolfgang (Pullman, WA); Hegland, Joel E. (Pullman, WA); Jones, Scott C. (Pullman, WA)

    1991-01-01

    Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission.

  1. Remote radiation dosimetry

    DOEpatents

    Braunlich, P.F.; Tetzlaff, W.; Hegland, J.E.; Jones, S.C.

    1991-03-12

    Disclosed are methods and apparatus for remotely measuring radiation levels. Such are particularly useful for measuring relatively high levels or dosages of radiation being administered in radiation therapy. They are also useful for more general radiation level measurements where remote sensing from the remaining portions of the apparatus is desirable. The apparatus uses a beam generator, such as a laser beam, to provide a stimulating beam. The stimulating beam is preferably of wavelengths shorter than 6 microns, or more advantageously less than 2 microns. The stimulating beam is used to stimulate a remote luminescent sensor mounted in a probe which emits stored luminescent energy resulting from exposure of the sensor to ionizing radiation. The stimulating beam is communicated to the remote luminescent sensor via a transmissive fiber which also preferably serves to return the emission from the luminescent sensor. The stimulating beam is advantageously split by a beam splitter to create a detector beam which is measured for power during a reading period during which the luminescent phosphor is read. The detected power is preferably used to control the beam generator to thus produce desired beam power during the reading period. The luminescent emission from the remote sensor is communicated to a suitable emission detector, preferably after filtering or other selective treatment to better isolate the luminescent emission. 8 figures.

  2. Reducing Radiation Damage

    SciTech Connect

    Blankenbecler, Richard

    2006-06-05

    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.

  3. Lunar radiator shade

    NASA Technical Reports Server (NTRS)

    Ewert, Michael K. (inventor)

    1992-01-01

    An apparatus for rejecting waste heat from a system located on or near the lunar equator is presented. The system utilizes a reflective catenary shaped trough deployed about a vertical radiator to shade the radiator from heat emitted by the hot lunar surface. The catenary shaped trough is constructed from a film material and is aligned relative to the sun so that incoming solar energy is focused to a line just above the vertical radiator and can thereby isolate the radiator from the effects of direct sunlight. The film is in a collapsed position between side by side support rods, all of which are in a transport case. To deploy the film and support rods, a set of parallel tracks running perpendicular to length of the support rods are extended out from the transport case. After the support tracks are deployed, the support rods are positioned equidistant from each other along the length of the support tracks so that the flexible film shade between adjacent support rods is unfolded and hangs in a catenary shaped trough. A heat radiator is supported between each pair of support rods above each hanging reflective trough.

  4. Ionizing radiation and life.

    PubMed

    Dartnell, Lewis R

    2011-01-01

    Ionizing radiation is a ubiquitous feature of the Cosmos, from exogenous cosmic rays (CR) to the intrinsic mineral radioactivity of a habitable world, and its influences on the emergence and persistence of life are wide-ranging and profound. Much attention has already been focused on the deleterious effects of ionizing radiation on organisms and the complex molecules of life, but ionizing radiation also performs many crucial functions in the generation of habitable planetary environments and the origins of life. This review surveys the role of CR and mineral radioactivity in star formation, generation of biogenic elements, and the synthesis of organic molecules and driving of prebiotic chemistry. Another major theme is the multiple layers of shielding of planetary surfaces from the flux of cosmic radiation and the various effects on a biosphere of violent but rare astrophysical events such as supernovae and gamma-ray bursts. The influences of CR can also be duplicitous, such as limiting the survival of surface life on Mars while potentially supporting a subsurface biosphere in the ocean of Europa. This review highlights the common thread that ionizing radiation forms between the disparate component disciplines of astrobiology. PMID:21774684

  5. Radiation from Relativistic Jets

    NASA Technical Reports Server (NTRS)

    Nishikawa, K.-I.; Mizuno, Y.; Hardee, P.; Sol, H.; Medvedev, M.; Zhang, B.; Nordlund, A.; Frederiksen, J. T.; Fishman, G. J.; Preece, R.

    2008-01-01

    Nonthermal radiation observed from astrophysical systems containing relativistic jets and shocks, e.g., gamma-ray bursts (GRBs), active galactic nuclei (AGNs), and Galactic microquasar systems usually have power-law emission spectra. Recent PIC simulations of relativistic electron-ion (electron-positron) jets injected into a stationary medium show that particle acceleration occurs within the downstream jet. In the presence of relativistic jets, instabilities such as the Buneman instability, other two-streaming instability, and the Weibel (filamentation) instability create collisionless shocks, which are responsible for particle (electron, positron, and ion) acceleration. The simulation results show that the Weibel instability is responsible for generating and amplifying highly nonuniform, small-scale magnetic fields. These magnetic fields contribute to the electron's transverse deflection behind the jet head. The 'jitter' radiation from deflected electrons in small-scale magnetic fields has different properties than synchrotron radiation which is calculated in a uniform magnetic field. This jitter radiation, a case of diffusive synchrotron radiation, may be important to understand the complex time evolution and/or spectral structure in gamma-ray bursts, relativistic jets, and supernova remnants.

  6. Packet personal radiation monitor

    DOEpatents

    Phelps, J.E.

    1988-03-31

    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 low-loss sensing network which generates a feedback signal to control the high voltage power supply such that the high voltage bias is recharged to +500 VDC when the current pulses of the sensor, generated by the detection of ionizing radiatonevents, discharges the high voltage bias to +450 VDC. During the high voltage recharge period an audio transducer is activated to produce an audible ''chirp''. The rate of the ''chirps'' is controlled by the rate at which the high voltage bias is recharged, which is proportional to the radiation field intensity to which the sensor is exposed. The chirp rate sensitivity is set to be approximately 1.5 (chirps/min/MR/hr.). The G-M tube sensor is used in a current sensing mode so that the device does not paralyze in a high radiation field. 2 figs.

  7. Characteristics of synchrotron radiation

    SciTech Connect

    Thomlinson, W.

    1984-01-01

    Synchrotron radiation is having a very significant impact on the many disciplines that make use of the radiation in the x-ray, vacuum ultraviolet, and infra-red regions of the spectrum. The rapidly increasing demand for beam time at existing facilities, the construction and commissioning of new facilities, and the world wide planning for future sources is clear testimony to the unique, interdisciplinary nature of the research applications. The nature of synchrotron radiation research continues to change and expand. This conference on the application of synchrotron radiation (SR) to polymer research illustrates that point. In this introductory paper it is impossible to cover in depth any of the applications. The intent, instead, is to give a brief, condensed summary of the properties of SR which have brought it to the fore as a research tool. No single source can provide the proper radiation for all applications. This paper should provide enough information and references to allow anyone contemplating a particular experiment to understand the widely varying parameters from different facilities, and thereby make some initial decisions concerning feasibility, and proper source. The NSLS will, in general, be used for illustration purposes since the conference is being held at Brookhaven where the attendees can get first hand familiarity with the facility.

  8. Audible radiation monitor

    SciTech Connect

    Odell, D.M.C.

    1992-12-31

    This invention consists of 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.

  9. Composition for radiation shielding

    DOEpatents

    Kronberg, J.W.

    1994-08-02

    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.

  10. Aerothermodynamic radiation studies

    NASA Technical Reports Server (NTRS)

    Donohue, K.; Reinecke, W. G.; Rossi, D.; Marinelli, W. J.; Krech, R. H.; Caledonia, G. E.

    1991-01-01

    We have built and made operational a 6 in. electric arc driven shock tube which alloys us to study the non-equilibrium radiation and kinetics of low pressure (0.1 to 1 torr) gases processed by 6 to 12 km/s shock waves. The diagnostic system allows simultaneous monitoring of shock radiation temporal histories by a bank of up to six radiometers, and spectral histories with two optical multi-channel analyzers. A data set of eight shots was assembled, comprising shocks in N2 and air at pressures between 0.1 and 1 torr and velocities of 6 to 12 km/s. Spectrally resolved data was taken in both the non-equilibrium and equilibrium shock regions on all shots. The present data appear to be the first spectrally resolved shock radiation measurements in N2 performed at 12 km/s. The data base was partially analyzed with salient features identified.

  11. Internal radiation attenuation system

    SciTech Connect

    Jacobson, E.B.

    1988-03-22

    This patent describes an internal radiation attenuation system for a radioactive environment having a substantially enclosed radioactive workspace having an internal configuration with at least one entrance portal. The workspace internal configuration has an upper wall or ceiling, side walls and a bottom wall, comprising: means for forming a frame for supporting radiation attenuation means to substantially conform to at least a portion of the inside of the workspace internal configuration. The frame means include interlocking segments, including means for assembling the segments into the frame means. The interlocking segments form a skeleton spaced around the periphery of the internal workspace, interlocked with one another. The frame means further include means for supporting the radiation attenuation means around at least a portion of the periphery of the internal workspace. The frame means skeleton form a free standing support structure standing and supported primarily by the bottom wall without vertical support from the ceiling.

  12. Solar cell radiation handbook

    NASA Technical Reports Server (NTRS)

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

    1982-01-01

    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 charged particles radiation with solar cells is discussed and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence are presented.

  13. Radiation induced oral mucositis.

    PubMed

    Ps, Satheesh Kumar; Balan, Anita; Sankar, Arun; Bose, Tinky

    2009-07-01

    PATIENTS RECEIVING RADIOTHERAPY OR CHEMOTHERAPY WILL RECEIVE SOME DEGREE OF ORAL MUCOSITIS THE INCIDENCE OF ORAL MUCOSITIS WAS ESPECIALLY HIGH IN PATIENTS: (i) With primary tumors in the oral cavity, oropharynx, or nasopharynx; (ii) who also received concomitant chemotherapy; (iii) who received a total dose over 5,000 cGy; and (iv) who were treated with altered fractionation radiation schedules. Radiation-induced oral mucositis affects the quality of life of the patients and the family concerned. The present day management of oral mucositis is mostly palliative and or supportive care. The newer guidelines are suggesting Palifermin, which is the first active mucositis drug as well as Amifostine, for radiation protection and cryotherapy. The current management should focus more on palliative measures, such as pain management, nutritional support, and maintenance, of good oral hygiene. PMID:20668585

  14. Uses of synchrotron radiation

    SciTech Connect

    Gordon, B.M.

    1982-01-01

    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.

  15. String radiative backreaction

    SciTech Connect

    Battye, R.A.; Shellard, E.P. [Department of Applied Mathematics and Theoretical Physics, University of Cambridge, Silver Street, Cambridge, CB3 9EW (United Kingdom)] [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

    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.}

  16. 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.

  17. LDEF Satellite Radiation Analyses

    NASA Technical Reports Server (NTRS)

    Armstrong, T. W.; Colborn, B. L.

    1996-01-01

    This report covers work performed by Science Applications International Corporation (SAIC) under contract NAS8-39386 from the NASA Marshall Space Flight Center entitled LDEF Satellite Radiation Analyses. The basic objective of the study was to evaluate the accuracy of present models and computational methods for defining the ionizing radiation environment for spacecraft in Low Earth Orbit (LEO) by making comparisons with radiation measurements made on the Long Duration Exposure Facility (LDEF) satellite, which was recovered after almost six years in space. The emphasis of the work here is on predictions and comparisons with LDEF measurements of induced radioactivity and Linear Energy Transfer (LET) measurements. These model/data comparisons have been used to evaluate the accuracy of current models for predicting the flux and directionality of trapped protons for LEO missions.

  18. Audible radiation monitor

    DOEpatents

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

    1993-01-01

    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.

  19. Semiconductor radiation detector

    DOEpatents

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

    2010-03-30

    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.

  20. Pediatric radiation oncology

    SciTech Connect

    Halperin, E.C.; Kun, L.E.; Constine, L.S.; Tarbell, N.J.

    1989-01-01

    This text covers all aspects of radiation therapy for treatment of pediatric cancer. The book describes the proper use of irradiation in each of the malignancies of childhood, including tumors that are rarely encountered in adult practice. These include acute leukemia; supratentorial brain tumors; tumors of the posterior fossa of the brain and spinal canal; retinoblastoma and optic nerve glioma; neuroblastoma; Hodgkin's disease; malignant lymphoma; Ewing's sarcoma; osteosarcoma; rhabdomyosarcoma; Desmoid tumor; Wilms' tumor; liver and biliary tumors; germ cell and stromal cell tumors of the gonads; endocrine, aerodigestive tract, and breast tumors; Langerhans' cell histiocytosis; and skin cancer and hemangiomas. For each type of malignancy, the authors describe the epidemiology, common presenting signs and symptoms, staging, and proper diagnostic workup. Particular attention is given to the indications for radiation therapy and the planning of a course of radiotherapy, including the optimal radiation dose, field size, and technique.

  1. Radiation in Particle Simulations

    SciTech Connect

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

    2009-06-15

    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.

  2. Saturn Radiation (SATRAD) Model

    NASA Technical Reports Server (NTRS)

    Garrett, H. B.; Ratliff, J. M.; Evans, R. W.

    2005-01-01

    The Saturnian radiation belts have not received as much attention as the Jovian radiation belts because they are not nearly as intense-the famous Saturnian particle rings tend to deplete the belts near where their peak would occur. As a result, there has not been a systematic development of engineering models of the Saturnian radiation environment for mission design. A primary exception is that of Divine (1990). That study used published data from several charged particle experiments aboard the Pioneer 1 1, Voyager 1, and Voyager 2 spacecraft during their flybys at Saturn to generate numerical models for the electron and proton radiation belts between 2.3 and 13 Saturn radii. The Divine Saturn radiation model described the electron distributions at energies between 0.04 and 10 MeV and the proton distributions at energies between 0.14 and 80 MeV. The model was intended to predict particle intensity, flux, and fluence for the Cassini orbiter. Divine carried out hand calculations using the model but never formally developed a computer program that could be used for general mission analyses. This report seeks to fill that void by formally developing a FORTRAN version of the model that can be used as a computer design tool for missions to Saturn that require estimates of the radiation environment around the planet. The results of that effort and the program listings are presented here along with comparisons with the original estimates carried out by Divine. In addition, Pioneer and Voyager data were scanned in from the original references and compared with the FORTRAN model s predictions. The results were statistically analyzed in a manner consistent with Divine s approach to provide estimates of the ability of the model to reproduce the original data. Results of a formal review of the model by a panel of experts are also presented. Their recommendations for further tests, analyses, and extensions to the model are discussed.

  3. Radiation Hazard Detector

    NASA Technical Reports Server (NTRS)

    1978-01-01

    NASA technology has made commercially available a new, inexpensive, conveniently-carried device for protection, of people exposed to potentially dangerous levels of microwave radiation. Microwaves are radio emissions of extremely high frequency. They can be hazardous but the degree of hazard is not yet well understood. Generally, it is believed that low intensity radiation of short duration is not harmful but that exposure to high levels can induce deep internal burns, affecting the circulatory and nervous systems, and particularly the eyes. The Department of Labor's Occupational Safety and Health Administration (OSHA) has established an allowable safe threshold of exposure. However, people working near high intensity sources of microwave energy-for example, radar antennas and television transmitters-may be unknowingly exposed to radiation levels beyond the safe limit. This poses not only a personal safety problem but also a problem for employers in terms of productivity loss, workman's compensation claims and possible liability litigation. Earlier-developed monitoring devices which warn personnel of dangerous radiation levels have their shortcomings. They can be cumbersome and awkward to use while working. They also require continual visual monitoring to determine if a person is in a dangerous area of radiation, and they are relatively expensive, another deterrent to their widespread adoption. In response to the need for a cheaper and more effective warning system, Jet Propulsion Laboratory developed, under NASA auspices, a new, battery-powered Microwave Radiation Hazard Detector. To bring the product to the commercial market, California Institute Research Foundation, the patent holder, granted an exclusive license to Cicoil Corporation, Chatsworth, California, an electronic components manufacturer.

  4. Small Active Radiation Monitor

    NASA Technical Reports Server (NTRS)

    Badhwar, Gautam D.

    2004-01-01

    A device, named small active radiation monitor, allows on-orbit evaluations during periods of increased radiation, after extravehicular activities, or at predesignated times for crews on such long-duration space missions as on the International Space Station. It also permits direct evaluation of biological doses, a task now performed using a combination of measurements and potentially inaccurate simulations. Indeed the new monitor can measure a full array of radiation levels, from soft x-rays to hard galactic cosmic-ray particles. With refinement, it will benefit commercial (nuclear power-plant workers, airline pilots, medical technicians, physicians/dentists, and others) and military personnel as well as the astronauts for whom thermoluminescent dosimeters are inadequate. Civilian and military personnel have long since graduated from film badges to thermoluminescent dosimeters. Once used, most dosimeters must be returned to a central facility for processing, a step that can take days or even weeks. While this suffices for radiation workers for whom exposure levels are typically very low and of brief duration, it does not work for astronauts. Even in emergencies and using express mail, the results can often be delayed by as much as 24 hours. Electronic dosimeters, which are the size of electronic oral thermometers, and tattlers, small electronic dosimeters that sound an alarm when the dose/dose rate exceeds preset values, are also used but suffer disadvantages similar to those of thermoluminescent dosimeters. None of these devices fully answers the need of rapid monitoring during the space missions. Instead, radiation is monitored by passive detectors, which are read out after the missions. Unfortunately, these detectors measure only the absorbed dose and not the biologically relevant dose equivalent. The new monitor provides a real-time readout, a time history of radiation exposures (both absorbed dose and biologically relevant dose equivalent), and a count of the number of particles passing through a unit area. Better still, the monitor can be used anywhere.

  5. Radiation Hydrodynamics in Supernovae

    NASA Astrophysics Data System (ADS)

    Höflich, Peter

    2005-07-01

    We discuss the current status of our hydrodynamical radiation (HYDRA) code for rapidly expanding, low-density envelopes commonly found in core collapse and thermonuclear supernovae. In supernovae, one of the main issues is the coupling between a radiation field and properties of the matter. Due to the low densities, nonthermal excitation by high-energy photons from radioactive decays and the time dependence of the problem, significant departures from local thermodynamical equilibrium (LTE) are common throughout the envelope even at large optical depths. This effect must be taken into account to simulate the evolution of spectra and light curves which are the basic tools to link between explosion physics and observations.

  6. Radiation monitor for liquids

    DOEpatents

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

    1999-01-01

    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.

  7. Radiation monitor for liquids

    DOEpatents

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

    1999-03-02

    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.

  8. Tunable terahertz radiation source

    DOEpatents

    Boulaevskii, Lev; Feldmann, David M; Jia, Quanxi; Koshelev, Alexei; Moody, Nathan A

    2014-01-21

    Terahertz radiation source and method of producing terahertz radiation, said source comprising a junction stack, said junction stack comprising a crystalline material comprising a plurality of self-synchronized intrinsic Josephson junctions; an electrically conductive material in contact with two opposing sides of said crystalline material; and a substrate layer disposed upon at least a portion of both the crystalline material and the electrically-conductive material, wherein the crystalline material has a c-axis which is parallel to the substrate layer, and wherein the source emits at least 1 mW of power.

  9. Radiation Detectors and Art

    NASA Astrophysics Data System (ADS)

    Denker, Andrea

    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).

  10. Solar cell radiation handbook

    NASA Technical Reports Server (NTRS)

    Tada, H. Y.; Carter, J. R., Jr.

    1977-01-01

    Solar cell theory cells are manufactured, and how they are modeled mathematically is reviewed. The interaction of energetic charged particle radiation with solar cells is discussed in detail and the concept of 1 MeV equivalent electron fluence is introduced. The space radiation environment is described and methods of calculating equivalent fluences for the space environment are developed. A computer program was written to perform the equivalent fluence calculations and a FORTRAN listing of the program is included. Finally, an extensive body of data detailing the degradation of solar cell electrical parameters as a function of 1 MeV electron fluence is presented.

  11. LDEF Satellite Radiation Analyses

    NASA Technical Reports Server (NTRS)

    Armstrong, T. W.; Colborn, B. L.

    1996-01-01

    Model calculations and analyses have been carried out to compare with several sets of data (dose, induced radioactivity in various experiment samples and spacecraft components, fission foil measurements, and LET spectra) from passive radiation dosimetry on the Long Duration Exposure Facility (LDEF) satellite, which was recovered after almost six years in space. The calculations and data comparisons are used to estimate the accuracy of current models and methods for predicting the ionizing radiation environment in low earth orbit. The emphasis is on checking the accuracy of trapped proton flux and anisotropy models.

  12. Unruh radiation and Interference effect

    E-print Network

    Satoshi Iso; Yasuhiro Yamamoto; Sen Zhang

    2011-02-23

    A uniformly accelerated charged particle feels the vacuum as thermally excited and fluctuates around the classical trajectory. Then we may expect additional radiation besides the Larmor radiation. It is called Unruh radiation. In this report, we review the calculation of the Unruh radiation with an emphasis on the interference effect between the vacuum fluctuation and the radiation from the fluctuating motion. Our calculation is based on a stochastic treatment of the particle under a uniform acceleration. The basics of the stochastic equation are reviewed in another report in the same proceeding. In this report, we mainly discuss the radiation and the interference effect.

  13. Thermostatic Radiator Valve Evaluation

    SciTech Connect

    Dentz, Jordan [Advanced Residential Integrated Energy Solutions Collaborative, New York, NY (United States); Ansanelli, Eric [Advanced Residential Integrated Energy Solutions Collaborative, New York, NY (United States)

    2015-01-01

    A large stock of multifamily buildings in the Northeast and Midwest are heated by steam distribution systems. Losses from these systems are typically high and a significant number of apartments are overheated much of the time. Thermostatically controlled radiator valves (TRVs) are one potential strategy to combat this problem, but have not been widely accepted by the residential retrofit market.

  14. RADIATION ALERT User Manual

    E-print Network

    Haller, Gary L.

    ." The Inspector counts ionizing events and displays the results on the liquid crystal display (LCD). You control Introduction 4 How the Inspector Detects Radiation 4 Precautions 4 2 Features 5 The Display 6 The Switches 7 Up 10 Display Update 10 Maximum Level 10 Response Time (Autoaveraging) 11 Operating in Dose Rate

  15. Radiation belts of Jupiter

    Microsoft Academic Search

    R. W. Fillius; C. E. McIlwain

    1974-01-01

    Pioneer 10 courted relativistic electrons throughout the magnetosphere ; of Jupiter, with the greatest fluxes being inside 20 Jupiter radii. The peak ; flux of electrons with energy greater than 50 MeV was 1.3 x 107 per square ; centimeter per second at the innermost penetration of the radiation belts. ; (auth);

  16. Radiation detector spectrum simulator

    DOEpatents

    Wolf, M.A.; Crowell, J.M.

    1985-04-09

    A small battery operated nuclear spectrum simulator having a noise source generates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith to generate several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  17. RADIATION CHEMISTRY OF GASES

    Microsoft Academic Search

    P. Harteck; S. Dondes

    1958-01-01

    The kinetic radiation equilibrium has only been obtained with two ; systems, nitrogen-oxygen, and carbon dioxide. In the case of the nitrogen--; oxygen system, the end results are nitrogen oxygen, nitrogen dioxide, and nitrous ; oxide, regardless of the initial material. Thus. if nitrous oxide or a 86.33 ; mixture of nitrogen to oxygen is the starting material, the concentrations

  18. 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...

  19. Local microwave background radiation

    E-print Network

    Domingos Soares

    2014-11-13

    An inquiry on a possible local origin for the Microwave Background Radiation is made. Thermal MBR photons are contained in a system called {\\it magnetic bottle} which is due to Earth magnetic field and solar wind particles, mostly electrons. Observational tests are anticipated.

  20. Ionizing radiation from tobacco

    SciTech Connect

    Westin, J.B.

    1987-04-24

    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.

  1. Surface Radiation Budget

    NASA Technical Reports Server (NTRS)

    Stackhouse, Paul W. (Principal Investigator)

    The Surface Radiation Budget (SRB) data sets contain global 3-hourly, daily and monthly averages of surface longwave and shortwave radiative properties, cloud amount, and meteorological properties computed using models. The main input data for these models include cloud information, top-of-atmosphere radiances and profiles of atmospheric water vapor and temperature. Some of the input data include Earth Radiation Budget Energy (ERBE) top-of-atmosphere clear-sky albedo and International Satellite Cloud Climatology Project (ISCCP) radiances and cloud amount. SRB parameters derived for the renewable energy community are also available from the Surface meteorology and Solar Energy (SSE) data set. Other SRB data are available from Clouds and the Earth's Radiant Energy System (CERES) and Multi-angle Imaging SpectroRadiometer (MISR). [Mission Objectives] The objective of the SRB Project is to produce and archive a global data set of shortwave (SW) and longwave (LW) surface and top of the atmosphere parameters. The data generated in the SRB project may be used in conjunction with other data sets to facilitate the development of renewable energy resources and increase understanding of radiative properties within the meteorological community. [Temporal_Coverage: Start_Date=1983-07-01; Stop_Date=2005-06-30] [Spatial_Coverage: Southernmost_Latitude=-90; Northernmost_Latitude=90; Westernmost_Longitude=-180; Easternmost_Longitude=180].

  2. Radiation detector spectrum simulator

    DOEpatents

    Wolf, Michael A. (Los Alamos, NM); Crowell, John M. (Los Alamos, NM)

    1987-01-01

    A small battery operated nuclear spectrum simulator having a noise source nerates pulses with a Gaussian distribution of amplitudes. A switched dc bias circuit cooperating therewith generates several nominal amplitudes of such pulses and a spectral distribution of pulses that closely simulates the spectrum produced by a radiation source such as Americium 241.

  3. Radiation Protection Basics

    MedlinePLUS

    ... have been contaminated or used for disposal of radioactive material. We also account for the shielding provided by buildings for a person working or living at a site that has been cleaned up. Health Effects This page describes the effects of radiation exposure.

  4. Photothermal solar radiation collectors

    Microsoft Academic Search

    M. M. Koltun; V. P. Matveev; I. P. Gavrilova

    1980-01-01

    The optical and energy characteristics of several types of photothermal combined solar radiation collectors are compared. Both steady-state and transient regimes are considered. The models evaluated are a flat collector and two types of evacuated tube collectors. Values are also derived for the heat-loss coefficient of each model. Computational and experimental results are compared. The most effective construction is found

  5. Radiations from hot nuclei

    NASA Technical Reports Server (NTRS)

    Malik, F. Bary

    1993-01-01

    The investigation indicates that nuclei with excitation energy of a few hundred MeV to BeV are more likely to radiate hot nuclear clusters than neutrons. These daughter clusters could, furthermore, de-excite emitting other hot nuclei, and the chain continues until these nuclei cool off sufficiently to evaporate primarily neutrons. A few GeV excited nuclei could radiate elementary particles preferentially over neutrons. Impact of space radiation with materials (for example, spacecraft) produces highly excited nuclei which cool down emitting electromagnetic and particle radiations. At a few MeV excitation energy, neutron emission becomes more dominant than gamma-ray emission and one often attributes the cooling to take place by successive neutron decay. However, a recent experiment studying the cooling process of 396 MeV excited Hg-190 casts some doubt on this thinking, and the purpose of this investigation is to explore the possibility of other types of nuclear emission which might out-compete with neutron evaporation.

  6. VDT Emissions Radiate Debate.

    ERIC Educational Resources Information Center

    Morgan, Bill

    1990-01-01

    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)

  7. Transition radiation detectors

    Microsoft Academic Search

    Boris Dolgoshein

    1993-01-01

    The use of transition radiation (TR) as a means of identifying high energy particles has now become a subject of intensive experimental investigations and applications. Our intention is first to study the physics of these phenomena and to describe ways of building detectors which can efficiently identify particles.

  8. Photovoltaic radiation detector element

    DOEpatents

    Agouridis, D.C.

    1980-12-17

    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 in the edge of which closely approaches but is spaced from the current collector strips.

  9. Compound semiconductor radiation detectors

    Microsoft Academic Search

    Alan Owens; A. Peacock

    2004-01-01

    We discuss the potential benefits of using compound semiconductors for the detection of X- and ?-ray radiation. While Si and Ge have become detection standards for energy dispersive spectroscopy in the laboratory, their use for an increasing range of applications is becoming marginalized by one or more of their physical limitations; namely the need for ancillary cooling systems or bulky

  10. Nuclear Radiation Detectors

    Microsoft Academic Search

    G. A. Morton

    1962-01-01

    Nuclear radiation detectors are required in all the major fields of nuclear science and technology. They fall into two principal categories, single element detectors and imaging detectors. Single element detectors can be classified into four types, based upon their physical mode of operation. These are 1) Scintillation counters, 2) Gas ionization detectors, a) Ionization chambers, b) Proportional counters, c) Geiger-Mueller

  11. Radiation penetration test

    Microsoft Academic Search

    Kannoo

    1973-01-01

    Radiation penetration tests are one of the nondestructive testing ; methods which are employed as a method of detecting internal defects with ; ultrasonic flaw detection. Of these, radiography is the most widely used method ; for defect detection, which produces two dimensional images of defects on x-ray ; films. Experimental investigations have been carried out for the defects to

  12. Acute radiation risk models

    NASA Astrophysics Data System (ADS)

    Smirnova, Olga

    Biologically motivated mathematical models, which describe the dynamics of the major hematopoietic lineages (the thrombocytopoietic, lymphocytopoietic, granulocytopoietic, and erythropoietic systems) in acutely/chronically irradiated humans are developed. These models are implemented as systems of nonlinear differential equations, which variables and constant parameters have clear biological meaning. It is shown that the developed models are capable of reproducing clinical data on the dynamics of these systems in humans exposed to acute radiation in the result of incidents and accidents, as well as in humans exposed to low-level chronic radiation. Moreover, the averaged value of the "lethal" dose rates of chronic irradiation evaluated within models of these four major hematopoietic lineages coincides with the real minimal dose rate of lethal chronic irradiation. The demonstrated ability of the models of the human thrombocytopoietic, lymphocytopoietic, granulocytopoietic, and erythropoietic systems to predict the dynamical response of these systems to acute/chronic irradiation in wide ranges of doses and dose rates implies that these mathematical models form an universal tool for the investigation and prediction of the dynamics of the major human hematopoietic lineages for a vast pattern of irradiation scenarios. In particular, these models could be applied for the radiation risk assessment for health of astronauts exposed to space radiation during long-term space missions, such as voyages to Mars or Lunar colonies, as well as for health of people exposed to acute/chronic irradiation due to environmental radiological events.

  13. Radiation Source Replacement Workshop

    SciTech Connect

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

    2010-12-01

    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.

  14. Nuclear Radiation Damages Minds!

    ERIC Educational Resources Information Center

    Blai, Boris, Jr.

    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…

  15. Psoriasis and ultraviolet radiation

    SciTech Connect

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

    1993-09-01

    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.

  16. Paradoxes of Thermal Radiation

    ERIC Educational Resources Information Center

    Besson, U.

    2009-01-01

    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 particular,…

  17. Continuum radiation at Uranus

    SciTech Connect

    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

    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.

  18. Dynamics of radiating fluids

    SciTech Connect

    Mihalas, D.; Weaver, R.

    1982-01-01

    The purpose of this paper is to give an overview of the role of radiation in the transport of energy and momentum in a combined matter-radiation fluid. The transport equation for a moving radiating fluid is presented in both a fully Eulerian and a fully Lagrangian formulation, along with conservation equations describing the dynamics of the fluid. Special attention is paid to the problem of deriving equations that are mutually consistent in each frame, and between frames, to 0(v/c). A detailed analysis is made to show that in situations of broad interest, terms that are formally of 0(v/c) actually dominate the solution, demonstrating that it is essential (1) to pay scrupulous attention to the question of the frame dependence in formulating the equations, and (2) to solve the equations to 0(v/c) in quite general circumstances. These points are illustrated in the context of the nonequilibrium radiation diffusion limit, and a sketch of how the Lagrangian equations are to be solved is presented.

  19. Foundations of radiation hydrodynamics

    Microsoft Academic Search

    D. Mihalas; B. W. Mihalas

    1984-01-01

    This book is the result of an attempt, over the past few years, to gather the basic tools required to do research on radiating flows in astrophysics. The microphysics of gases is discussed, taking into account the equation of state of a perfect gas, the first and second law of thermodynamics, the thermal properties of a perfect gas, the distribution

  20. Thermodynamics of Radiation Modes

    ERIC Educational Resources Information Center

    Pina, Eduardo; de la Selva, Sara Maria Teresa

    2010-01-01

    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…

  1. Gravitational radiation and relativity

    SciTech Connect

    Weber, J.; Karade, T.M.

    1986-01-01

    This book presents papers on general relativity and the theory of gravitational fields. Topics considered include gravitational antennas, the structure of the terrestrial planets and tidal friction theory, physical symmetry groups, gravitational collapse, rotation, the Hubble diagram, the problems of cosmology, electromagnetic radiation, and coordinate transformations.

  2. Cosmic microwave background radiation

    Microsoft Academic Search

    Lyman Page; David Wilkinson

    1999-01-01

    The cosmic microwave background radiation (CMBR) is widely interpreted as the thermal afterglow of a hot big bang. Measurements of the CMBR intensity as a function of frequency constrain the history of cosmic energetics. Measurements of the anisotropy in the CMBR temperature provide a snapshot of the distribution of fluctuations in the gravitational potential at the earliest stages of cosmic

  3. Shield against radiations

    SciTech Connect

    Grifoni, S.

    1988-02-23

    This patent describes a shield against ionizing radiations that comprises at least one layer of an aggregate-containing cement-based conglomerate or an aggregate-containing cement-based mortar wherein the aggregate consists essentially of floated galena or mixtures thereof which at least one boron mineral.

  4. Radiation injury of bone

    SciTech Connect

    Shimanovskaya, K.; Shiman, A.D.

    1983-01-01

    This monograph is devoted to the characteristics of radiation injuries arising in hitherto unaffected parts of the skeleton during the treatment of neoplasms by radiotherapy. These changes frequently accompany the beneficial effects of radiotherapy, and can easily be misunderstood in the absence of any clear idea of their character. An understanding of the mechanism and conditions of appearance of radiation injuries of the skeleton and a knowledge of their clinical and radiological features are essential for physicians and surgeons caring for patients who have been treated by using radiotherapy and for experimental scientists whose work involves such methods. The effect of irradiation is determined by the topographical relations within the irradiated object, the character of distribution of the dose, and the size of the dose. The radiation injuries of the skeleton described in the book were observed during the treatment of carcinoma of the breast, lung, esophagus, and uterus, of malignant tumors in the mouth, certain pituitary tumors, and hemangiomas of the skin in children, by means of ionizing radiation obtained from various sources. A few observations relate to patients treated for certain other diseases. The text is illustrated by roentgenograms on the basis of which the diagnoses were made and the course of the lesion was subsequently confirmed, and also by operative and histological specimens. The book also contains many schemes drawn from roentgenograms.

  5. Radiation therapy: posterior segment complications.

    PubMed

    Seregard, Stefan; Pelayes, David E; Singh, Arun D

    2013-01-01

    Therapeutic radiation to the posterior segment of the eye is a common option for posterior segment tumors. Such tumors are often malignant, but sometimes, benign neoplasms are treated with ionizing radiation. Also, non-neoplastic intraocular lesions like wet age-related macular degeneration may be treated with radiotherapy. Orbital disease, both neoplastic lesions like optic nerve sheath meningioma and non-neoplastic entities like Graves' ophthalmopathy may be treated with radiotherapy and this may include radiation of the optic nerve and posterior segment of the eye. Occasionally, radiotherapy of extraocular malignant disease, involving, e.g. the paranasal sinuses, may cause significant radiation damage to the eye. Complications after radiation to the posterior segment of the eye are largely related to the radiation dose to the posterior segment. The amount of irradiated volume of normal tissue and fractionation are also important for the development of radiation complications to the posterior segment. Radiation retinopathy is the most common complication of the posterior segment, but radiation optic neuropathy also occurs frequently. Radiation scleral necrosis is less frequent probably due to the radioresistance of the scleral collagen. These complications have the potential to cause blindness (radiation retinopathy and optic neuropathy) or enucleation of the eye (scleral necrosis). Although numerous treatments have been advocated, management of radiation-induced damage remains controversial. Efficacy for any treatment still needs to be proven and, if possible, the best option by far is to minimize radiation changes to normal tissue. PMID:23989132

  6. Radiation proteomics: a brief overview.

    PubMed

    Leszczynski, Dariusz

    2014-03-01

    Acute biological effects caused by the exposure to high doses of radiation, either ionizing or nonionizing, are relatively well-known but the delayed effects, occurring decades after exposure, are difficult to predict. The knowledge of the acute and delayed effects of the low doses of ionizing radiation (e.g. bystander effect) or nonionizing radiation (e.g. radiation emitted by wireless communication devices) is not yet reliably established. Often the acute effects of low doses are small and difficult to discover and replicate in scientific studies. Chronic effects of prolonged exposures to low-dose radiation for decades are virtually unknown and often not possible to predict on the basis of the knowledge gained from acute exposures to high doses of radiation. Physiological significance of the biological effects induced by low doses of radiation is not known. The same lack of predictability of outcomes applies to the delayed effects of high-dose radiation exposures. Proteomics, supplemented with other "omics" techniques, might be the best way forward to find out the target molecules of radiation, the biomarkers of radiation exposure and the physiological and health significance of the acute and delayed biological effects caused by the exposures to high- and low-dose radiation. However, the currently available database of radiation effects on proteomes is far too small to be useful in formulation of new hypotheses concerning health consequences of radiation exposures. PMID:24376023

  7. Multidimensional radiative transfer in stratified atmospheres - Gray radiative equilibrium

    Microsoft Academic Search

    F. Kneer; J. N. Heasley

    1979-01-01

    This paper tests the validity of the multidimensional Eddington, or diffusion, approximation in radiative transfer in a gray radiative-equilibrium atmosphere with opacity increasing exponentially toward the stellar interior. The diffusion approximation is unacceptable at small optical depths. The height dependence of intensity fluctuations is studied systematically by adopting the above simplified model atmosphere for the solar photosphere. Lateral radiative exchange

  8. DCTD — Radiation Research Program (RRP)

    Cancer.gov

    Of the many successful programs within the RRP grant and contract portfolio, several scientific advances are presented below, representing significant advances in treatment development, molecular radiation therapy, quality assurance for high-technology radiation therapy, and international networking.

  9. 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 ...

  10. Radiation Therapy for Gynecologic Cancers

    MedlinePLUS

    ... Typically, radiation therapy is done with high energy X-rays, or photons, for the bulk of the treatment. Diff erent techniques can be used for treatment. Three- dimensional conformal radiotherapy (3-D CRT) combines multi- ple radiation treatment ...

  11. Acceleration and Classical Electromagnetic Radiation

    E-print Network

    E. N. Glass

    2008-01-09

    Classical radiation from an accelerated charge is reviewed along with the reciprocal topic of accelerated observers detecting radiation from a static charge. This review commemerates Bahram Mashhoon's 60th birthday.

  12. Conical electromagnetic radiation flux concentrator

    NASA Technical Reports Server (NTRS)

    Miller, E. R.

    1972-01-01

    Concentrator provides method of concentrating a beam of electromagnetic radiation into a smaller beam, presenting a higher flux density. Smaller beam may be made larger by sending radiation through the device in the reverse direction.

  13. RADIATION SAFETY OFFICE UNIVERSITYOF MARYLAND

    E-print Network

    Rubloff, Gary W.

    RADIATION SAFETY OFFICE UNIVERSITYOF MARYLAND RADIATION SAFETY MANUAL UNIVERSITY OF MARYLAND College Park, Maryland Revised May 2001 #12;TABLE OF CONTENTS FORWARD . . . . . . . . . . . . . . . . . . . . . . . . 11 2.3.4.2. University of Maryland Personnel Visiting Other Facilities . . . . . . . . . . . . . 11 2

  14. Simple device measures solar radiation

    NASA Technical Reports Server (NTRS)

    Humphries, W. R.

    1977-01-01

    Simple inexpensive thermometer, insolated from surroundings by transparent glass or plastic encasement, measures intensities of solar radiation, or radiation from other sources such as furnaces or ovens. Unit can be further modified to accomplish readings from remote locations.

  15. Doses from Medical Radiation Sources

    MedlinePLUS

    ... settings of the machine used to produce the radiation, in nuclear medicine on the amount of activity administered and ... and magnitude of occupational and public exposures from nuclear medicine ... Radiation Protection and Measurements; NCRP Report 124; 1996. United ...

  16. Gamma radiation field intensity meter

    DOEpatents

    Thacker, Louis H. (Knoxville, TN)

    1995-01-01

    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.

  17. Gamma radiation field intensity meter

    DOEpatents

    Thacker, L.H.

    1995-10-17

    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.

  18. Gamma radiation field intensity meter

    DOEpatents

    Thacker, Louis H. (Knoxville, TN)

    1994-01-01

    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.

  19. Gamma radiation field intensity meter

    DOEpatents

    Thacker, L.H.

    1994-08-16

    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.

  20. Multiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation Response Effects of Radiation Quality and HypoxiaEffects of Radiation Quality and Hypoxia

    E-print Network

    Stewart, Robert D.

    Multiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation ResponseMultiscale Modeling of Radiation Response Effects of Radiation Quality and HypoxiaEffects of Radiation Quality and Hypoxia Robert D. Stewart, Ph.D.Robert D. Stewart, Ph

  1. Radiation effect on implanted pacemakers

    SciTech Connect

    Pourhamidi, A.H.

    1983-10-01

    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.

  2. Prevention of pelvic radiation disease.

    PubMed

    Fuccio, Lorenzo; Frazzoni, Leonardo; Guido, Alessandra

    2015-02-01

    Pelvic cancers are among the most frequently diagnosed cancers worldwide. Treatment of patients requires a multidisciplinary approach that frequently includes radiotherapy. Gastrointestinal (GI) radiation-induced toxicity is a major complication and the transient or long-term problems, ranging from mild to very severe, arising in non-cancerous tissues resulting from radiation treatment to a tumor of pelvic origin, are actually called as pelvic radiation disease. The incidence of pelvic radiation disease changes according to the radiation technique, the length of follow up, the assessment method, the type and stage of cancer and several other variables. Notably, even with the most recent radiation techniques, i.e., intensity-modulated radiotherapy, the incidence of radiation-induced GI side effects is overall reduced but still not negligible. In addition, radiation-induced GI side effects can develop even after several decades; therefore, the improvement of patient life expectancy will unavoidably increase the risk of developing radiation-induced complications. Once developed, the management of pelvic radiation disease may be challenging. Therefore, the prevention of radiation-induced toxicity represents a reasonable way to avoid a dramatic drop of the quality of life of these patients. In the current manuscript we provide an updated and practical review on the best available evidences in the field of the prevention of pelvic radiation disease. PMID:25664197

  3. Future status of radiation breeding

    Microsoft Academic Search

    Tanaka

    1973-01-01

    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

  4. Spectroscopy Interaction of electromagnetic radiation

    E-print Network

    Gerwert, Klaus

    Spectroscopy 691 Interaction of electromagnetic radiation with atoms or molecules #12;Bacteriorhodopsin: a light-driven proton pump 486 #12;Electromagnetic Radiation 692 harmonic wave (Maxwell): y;Spectroscopy 691 Interaction of electromagnetic radiation with atoms or molecules two processes: emission

  5. Prevention of pelvic radiation disease

    PubMed Central

    Fuccio, Lorenzo; Frazzoni, Leonardo; Guido, Alessandra

    2015-01-01

    Pelvic cancers are among the most frequently diagnosed cancers worldwide. Treatment of patients requires a multidisciplinary approach that frequently includes radiotherapy. Gastrointestinal (GI) radiation-induced toxicity is a major complication and the transient or long-term problems, ranging from mild to very severe, arising in non-cancerous tissues resulting from radiation treatment to a tumor of pelvic origin, are actually called as pelvic radiation disease. The incidence of pelvic radiation disease changes according to the radiation technique, the length of follow up, the assessment method, the type and stage of cancer and several other variables. Notably, even with the most recent radiation techniques, i.e., intensity-modulated radiotherapy, the incidence of radiation-induced GI side effects is overall reduced but still not negligible. In addition, radiation-induced GI side effects can develop even after several decades; therefore, the improvement of patient life expectancy will unavoidably increase the risk of developing radiation-induced complications. Once developed, the management of pelvic radiation disease may be challenging. Therefore, the prevention of radiation-induced toxicity represents a reasonable way to avoid a dramatic drop of the quality of life of these patients. In the current manuscript we provide an updated and practical review on the best available evidences in the field of the prevention of pelvic radiation disease. PMID:25664197

  6. Radiation and Health Thormod Henriksen

    E-print Network

    Johansen, Tom Henning

    Radiation and Health by Thormod Henriksen and Biophysics group at UiO #12;Preface The present book. The address is: http://www.mn.uio.no/fysikk/tjenester/kunnskap/straling/ III. Radiation and Health Written of ionizing radiation. Efforts were made to describe the background ra- diation as well as the release

  7. Radiation Therapy Technology Professional Curriculum

    E-print Network

    Berdichevsky, Victor

    Radiation Therapy Technology Professional Curriculum Fall Semester RT 3000 Concepts of Clinical Care RT 3010 Introductory Radiation Physics RT 3310 Clinical Practicum I RT 3110 Clinical Aspects of Radiation Therapy Semester Total Credits 12 Winter Semester RT 5650 Pathophysiology for Health Sciences RT

  8. Radiation Protection Guidance Hospital Staff

    E-print Network

    Kay, Mark A.

    Page 1 Radiation Protection Guidance For Hospital Staff Prepared for Stanford The privilege to use ionizing radiation at Stanford University, Stanford Hospital and Clinics, Lucile Packard with radioactive materials or radiation devices are responsible for knowing and adhering to applicable requirements

  9. Modelling radiative mean absorption coefficients

    Microsoft Academic Search

    J.-F. Ripoll; B. Dubroca; G. Duffa

    2001-01-01

    We define and compute mean absorption coefficients for the macroscopic models of radiative transfer. These coefficients take into account the anisotropic form of the photon emission and lead to a better computation of a photonic flow far from the radiative equilibrium. They are deduced by averaging a specific radiative intensity on the space of frequency and are generalized versions of

  10. Pregnancy and Radiation Protection

    NASA Astrophysics Data System (ADS)

    Gerogiannis, J.; Stefanoyiannis, A. P.

    2010-01-01

    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.

  11. Space Radiation Cancer Risks

    NASA Technical Reports Server (NTRS)

    Cucinotta, Francis A.

    2007-01-01

    Space radiation presents major challenges to astronauts on the International Space Station and for future missions to the Earth s moon or Mars. Methods used to project risks on Earth need to be modified because of the large uncertainties in projecting cancer risks from space radiation, and thus impact safety factors. We describe NASA s unique approach to radiation safety that applies uncertainty based criteria within the occupational health program for astronauts: The two terrestrial criteria of a point estimate of maximum acceptable level of risk and application of the principle of As Low As Reasonably Achievable (ALARA) are supplemented by a third requirement that protects against risk projection uncertainties using the upper 95% confidence level (CL) in the radiation cancer projection model. NASA s acceptable level of risk for ISS and their new lunar program have been set at the point-estimate of a 3-percent risk of exposure induced death (REID). Tissue-averaged organ dose-equivalents are combined with age at exposure and gender-dependent risk coefficients to project the cumulative occupational radiation risks incurred by astronauts. The 95% CL criteria in practice is a stronger criterion than ALARA, but not an absolute cut-off as is applied to a point projection of a 3% REID. We describe the most recent astronaut dose limits, and present a historical review of astronaut organ doses estimates from the Mercury through the current ISS program, and future projections for lunar and Mars missions. NASA s 95% CL criteria is linked to a vibrant ground based radiobiology program investigating the radiobiology of high-energy protons and heavy ions. The near-term goal of research is new knowledge leading to the reduction of uncertainties in projection models. Risk projections involve a product of many biological and physical factors, each of which has a differential range of uncertainty due to lack of data and knowledge. The current model for projecting space radiation cancer risk relies on the three assumptions of linearity, additivity, and scaling along with the use of population averages. We describe uncertainty estimates for this model, and new experimental data that sheds light on the accuracy of the underlying assumptions. These methods make it possible to express risk management objectives in terms of quantitative metrics, i.e., the number of days in space without exceeding a given risk level within well defined confidence limits. The resulting methodology is applied to several human space exploration mission scenarios including lunar station, deep space outpost, and a Mars mission. Factors that dominate risk projection uncertainties and application of this approach to assess candidate mitigation approaches are described.

  12. Pregnancy and Radiation Protection

    SciTech Connect

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

    2010-01-21

    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.

  13. Acute Cerebrovascular Radiation Syndrome: Radiation Neurotoxicity , mechanisms of CNS radiation injury, advanced countermeasures for Radiation Protection of Central Nervous System.

    NASA Astrophysics Data System (ADS)

    Popov, Dmitri; Jones, Jeffrey; Maliev, Slava

    Key words: Cerebrovascular Acute Radiation Syndrome (Cv ARS), Radiation Neurotoxins (RNT), Neurotransmitters, Radiation Countermeasures, Antiradiation Vaccine (ArV), Antiradiation Blocking Antibodies, Antiradiation Antidote. Psychoneuroimmunology, Neurotoxicity. ABSTRACT: To review the role of Radiation Neurotoxins in triggering, developing of radiation induced central nervous system injury. Radiation Neurotoxins - rapidly acting blood toxic lethal agent, which activated after irradiation and concentrated, circulated in interstitial fluid, lymph, blood with interactions with cell membranes, receptors and cell compartments. Radiation Neurotoxins - biological molecules with high enzymatic activity and/or specific lipids and activated or modified after irradiation. The Radiation Neurotoxins induce increased permeability of blood vessels, disruption of the blood-brain barrier, blood-cerebrospinal fluid (CSF) barrier and developing severe disorder of blood macro- and micro-circulation. Principles of Radiation Psychoneuro-immunology and Psychoneuro-allergology were applied for determination of pathological processes developed after irradiation or selective administration of Radiation Neurotoxins to radiation naïve mammals. Effects of radiation and exposure to radiation can develop severe irreversible abnormalities of Central Nervous System, brain structures and functions. Antiradiation Vaccine - most effective, advanced methods of protection, prevention, mitigation and treatment and was used for of Acute Radiation Syndromes and elaboration of new technology for immune-prophylaxis and immune-protection against ?, Heavy Ion, Neutron irradiation. Results of experiments suggested that blocking, antitoxic, antiradiation antibodies can significantly reduce toxicity of Radiation Toxins. New advanced technology include active immune-prophylaxis with Antiradiation Vaccine and Antiradiation therapy that included specific blocking antibodies to Radiation Neurotoxins. Antiradiation Vaccine and Antiradiation IgG preparations - prospective effective antidote/countermeasure for ?-irradiation, heavy ions irradiation, neutron irradiation. Recommendations for treatment and immune-prophylaxis of CNS injury, induced by radiation, were proposed. Specific immune therapy and specific immune prophylaxis reduce symptoms of ACvRS. This manuscript summarizes the results of experiments and considering possibility for blocking toxicological mechanisms of action of Radiation and Radiation Neurotoxins and prevention or diminishing clinical signs of injury of CNS. Experimental data suggest that Antiradiation vaccine and Antiradiation IgG with specific antibodies to Radiation Neurotoxins, Cytotoxins protect CNS against high doses of radiation.

  14. Radiation Induced Genomic Instability

    SciTech Connect

    Morgan, William F.

    2011-03-01

    Radiation induced genomic instability can be observed in the progeny of irradiated cells multiple generations after irradiation of parental cells. The phenotype is well established both in vivo (Morgan 2003) and in vitro (Morgan 2003), and may be critical in radiation carcinogenesis (Little 2000, Huang et al. 2003). Instability can be induced by both the deposition of energy in irradiated cells as well as by signals transmitted by irradiated (targeted) cells to non-irradiated (non-targeted) cells (Kadhim et al. 1992, Lorimore et al. 1998). Thus both targeted and non-targeted cells can pass on the legacy of radiation to their progeny. However the radiation induced events and cellular processes that respond to both targeted and non-targeted radiation effects that lead to the unstable phenotype remain elusive. The cell system we have used to study radiation induced genomic instability utilizes human hamster GM10115 cells. These cells have a single copy of human chromosome 4 in a background of hamster chromosomes. Instability is evaluated in the clonal progeny of irradiated cells and a clone is considered unstable if it contains three or more metaphase sub-populations involving unique rearrangements of the human chromosome (Marder and Morgan 1993). Many of these unstable clones have been maintained in culture for many years and have been extensively characterized. As initially described by Clutton et al., (Clutton et al. 1996) many of our unstable clones exhibit persistently elevated levels of reactive oxygen species (Limoli et al. 2003), which appear to be due dysfunctional mitochondria (Kim et al. 2006, Kim et al. 2006). Interestingly, but perhaps not surprisingly, our unstable clones do not demonstrate a “mutator phenotype” (Limoli et al. 1997), but they do continue to rearrange their genomes for many years. The limiting factor with this system is the target – the human chromosome. While some clones demonstrate amplification of this chromosome and thus lend themselves to prolonged study, many tend to eliminate or rearrange the target chromosome until it is too small for further rearrangement. The observed frequency of induced instability by low and high linear-energy-transfer radiations greatly exceeds that observed for nuclear gene mutations at similar doses; hence, mutation of a gene or gene family is unlikely to be the initiating mechanism. Once initiated however, there is evidence in the GM10115 model system that it can be perpetuated over time by dicentric chromosome formation followed by bridge breakage fusion cycles (Marder and Morgan 1993), as well as recombinational events involving interstitial telomere like repeat sequences (Day et al. 1998). There is also increasing evidence that inflammatory type reactions (Lorimore et al. 2001, Lorimore and Wright 2003), presumably involving reactive oxygen and nitrogen species as well as cytokines and chemokines might be involved in driving the ustable phenotype (Liaikis et al. 2007, Hei et al. 2008). To this end there is very convincing evidence for such reactions being involved in another non-targeted effect associated with ionizing radiation, the bystander effect (Hei et al. 2008). Clearly the link between induced instability and bystander effects suggests common processes and inflammatory type reactions will likely be the subject of future investigation.

  15. Aharonov-Bohm Radiation

    E-print Network

    Katherine Jones-Smith; Harsh Mathur; Tanmay Vachaspati

    2010-01-25

    A solenoid oscillating in vacuum will pair produce charged particles due to the Aharonov-Bohm (AB) interaction. We calculate the radiation pattern and power emitted for charged scalar particles. We extend the solenoid analysis to cosmic strings, and find enhanced radiation from cusps and kinks on loops. We argue by analogy with the electromagnetic AB interaction that cosmic strings should emit photons due to the gravitational AB interaction of fields in the conical spacetime of a cosmic string. We calculate the emission from a kink and find that it is of similar order as emission from a cusp, but kinks are vastly more numerous than cusps and may provide a more interesting observational signature.

  16. Genetic susceptibility to radiation

    NASA Astrophysics Data System (ADS)

    Hall, E. J.; Brenner, D. J.; Worgul, B.; Smilenov, L.

    In the context of space radiation, it is important to know whether the human population includes genetically predisposed radiosensitive subsets. One possibility is that haploinsufficiency for ATM confers radiosensitivity, and this defect involves 1-3% of the population. Using knock-out mice we chose to study cataractogenesis in the lens and oncogenic transformation in mouse embryo fibroblasts to assay for effects of ATM deficiency. Radiation induced cataracts appeared earlier in the heterozygous versus wild-type animals following exposure to either gamma rays or 1 GeV/nucleon iron ions. In addition, it was found that embryo fibroblasts of Atm heterozygotes showed an increased incidence of oncogenic transformation compared with their normal litter-matched counterparts. From these data we suggest that Ataxia Telangiectasia heterozygotes could indeed represent a societally-significant radiosensitive subpopulation.

  17. Semiconductor radiation detector

    DOEpatents

    Patt, Bradley E. (Sherman Oaks, CA); Iwanczyk, Jan S. (Los Angeles, CA); Tull, Carolyn R. (Orinda, CA); Vilkelis, Gintas (Westlake Village, CA)

    2002-01-01

    A semiconductor radiation detector is provided to detect x-ray and light photons. The entrance electrode is segmented by using variable doping concentrations. Further, the entrance electrode is physically segmented by inserting n+ regions between p+ regions. The p+ regions and the n+ regions are individually biased. The detector elements can be used in an array, and the p+ regions and the n+ regions can be biased by applying potential at a single point. The back side of the semiconductor radiation detector has an n+ anode for collecting created charges and a number of p+ cathodes. Biased n+ inserts can be placed between the p+ cathodes, and an internal resistor divider can be used to bias the n+ inserts as well as the p+ cathodes. A polysilicon spiral guard can be implemented surrounding the active area of the entrance electrode or surrounding an array of entrance electrodes.

  18. Radiative B Decays

    SciTech Connect

    Bard, D.; /Imperial Coll., London

    2011-11-23

    I discuss recent results in radiative B decays from the Belle and BaBar collaborations. I report new measurements of the decay rate and CP asymmetries in b {yields} s{gamma} and b {yields} d{gamma} decays, and measurements of the photon spectrum in b {yields} s{gamma}. Radiative penguin decays are flavour changing neutral currents which do not occur at tree level in the standard model (SM), but must proceed via one loop or higher order diagrams. These transitions are therefore suppressed in the SM, but offer access to poorlyknown SM parameters and are also a sensitive probe of new physics. In the SM, the rate is dominated by the top quark contribution to the loop, but non-SM particles could also contribute with a size comparable to leading SM contributions. The new physics effects are potentially large which makes them theoretically very interesting, but due to their small branching fractions they are typically experimentally challenging.

  19. National Ambient Radiation Database

    SciTech Connect

    Dziuban, J.; Sears, R.

    2003-02-25

    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.

  20. The Radiative Stress Tensor

    E-print Network

    Xinzhong Chen; Edward A. Spiegel

    2000-03-31

    We use the transfer equation in relativistic form to develop an expansion of the one-photon distribution for a medium with constant photon mean free path, $\\epsilon$. The resulting radiative viscosity tensor may be expressed either as a simple integral operator acting on the Thomas stress tensor or as the solution of an inhomogenous, linear partial differential equation. The expression obtained for the radiative viscosity tensor applies for media with long, as well as short, photon mean free paths. We also develop results applicable for relatively smooth flows by using the form of the Thomas stress tensor with generalized transport coefficients derived by the application of a suitable operator to the bare Thomas coefficients.

  1. Radiative Bulk Viscosity

    E-print Network

    X. Chen; E. A. Spiegel

    2001-02-01

    Viscous resistance to changes in the volume of a gas arises when different degrees of freedom have different relaxation times. Collisions tend to oppose the resulting departures from equilibrium and, in so doing, generate entropy. Even for a classical gas of hard spheres, when the mean free paths or mean flight times of constituent particles are long, we find a nonvanishing bulk viscosity. Here we apply a method recently used to uncover this result for a classical rarefied gas to radiative transfer theory and derive an expression for the radiative stress tensor for a gray medium with absorption and Thomson scattering. We determine the transport coefficients through the calculation of the comoving entropy generation. When scattering dominates absorption, the bulk viscosity becomes much larger than either the shear viscosity or the thermal conductivity.

  2. Radiation shielding composition

    DOEpatents

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

    2000-12-26

    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.

  3. Radiation shielding composition

    DOEpatents

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

    1998-01-01

    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.

  4. Terahertz radiation mixer

    DOEpatents

    Wanke, Michael C. (Albuquerque, NM); Allen, S. James (Santa Barbara, CA); Lee, Mark (Albuquerque, NM)

    2008-05-20

    A terahertz radiation mixer comprises a heterodyned field-effect transistor (FET) having a high electron mobility heterostructure that provides a gatable two-dimensional electron gas in the channel region of the FET. The mixer can operate in either a broadband pinch-off mode or a narrowband resonant plasmon mode by changing a grating gate bias of the FET. The mixer can beat an RF signal frequency against a local oscillator frequency to generate an intermediate frequency difference signal in the microwave region. The mixer can have a low local oscillator power requirement and a large intermediate frequency bandwidth. The terahertz radiation mixer is particularly useful for terahertz applications requiring high resolution.

  5. Time encoded radiation imaging

    SciTech Connect

    Marleau, Peter; Brubaker, Erik; Kiff, Scott

    2014-10-21

    The various technologies presented herein relate to detecting nuclear material at a large stand-off distance. An imaging system is presented which can detect nuclear material by utilizing time encoded imaging relating to maximum and minimum radiation particle counts rates. The imaging system is integrated with a data acquisition system that can utilize variations in photon pulse shape to discriminate between neutron and gamma-ray interactions. Modulation in the detected neutron count rates as a function of the angular orientation of the detector due to attenuation of neighboring detectors is utilized to reconstruct the neutron source distribution over 360 degrees around the imaging system. Neutrons (e.g., fast neutrons) and/or gamma-rays are incident upon scintillation material in the imager, the photons generated by the scintillation material are converted to electrical energy from which the respective neutrons/gamma rays can be determined and, accordingly, a direction to, and the location of, a radiation source identified.

  6. Radiation optic neuropathy

    SciTech Connect

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

    1985-08-01

    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.

  7. Radiation-Induced Cardiomyopathy

    PubMed Central

    Khan, M. Yusuf

    1973-01-01

    This investigation demonstrates sequential ultrastructural lesions of cardiac myocytes in rabbits exposed locally to a single dose (1008 and 1300 rads) of x-irradiation. A wide spectrum of lesions were observed as early as 24 hours postirradiation and were followed for as long as 4 months after x-irradiation. Myofibrillar degeneration and dissociation of intercalated discs seen at 24 and 48 hours postirradiation were followed by gradual progression of myofibrillolysis and myofiber degeneration to myofiber atrophy, myofiber collapse and eventual progressive pericellular interstitial myocardial fibrosis. The possible role of dissociation of intercalated disca in the pathogenesis of well-known postirradiation electrocardiographic changes is suggested. Myofibrillar degeneration appears to be the characteristic (although non-specific) lesion of radiation having a multifactorial etiology: direct radiation effect, vascular compromise and endogenous (cardiac) catecholamine liberation. ImagesFig 1Fig 2Fig 9Fig 10Fig 11Fig 12Fig 3Fig 4Fig 5Fig 6Fig 7Fig 8 PMID:4749211

  8. Radiation degradation of cellulose

    NASA Astrophysics Data System (ADS)

    Leonhardt, J.; Arnold, G.; Baer, M.; Langguth, H.; Gey, M.; Hübert, S.

    The application of straw and other cellulose polymers as feedstuff for ruminants is limited by its low digestibility. During recent decades it was attempted to increase the digestibility of straw by several chemical and physical methods. In this work some results of the degradation of gamma and electron treated wheat straw are reported. Complex methods of treatment (e.g. radiation influence and influence of lyes) are taken into consideration. In vitro-experiments with radiation treated straw show that the digestibility can be increased from 20 % up to about 80 %. A high pressure liquid chromatography method was used to analyze the hydrolysates. The contents of certain species of carbohydrates in the hydrolysates in dependence on the applied dose are given.

  9. Radiation therapy: orbital tumors.

    PubMed

    Marwaha, Gaurav; Macklis, Roger; Singh, Arun D

    2013-01-01

    Orbital tumors are rare overall, comprising 0.1% of all tumors and less than 20% of all orbital diseases. Tumors may be benign, locally aggressive, or malignant. Of the malignant tumors, lymphomas and metastases are the most common and are primarily seen in the elderly population. While surgery and chemotherapeutic agents are often employed in the management of these lesions, not all patients are candidates for these therapies. Radiation therapy offers a noninvasive, well-tolerated primary treatment modality, whereby vision-sparing is feasible in many cases. In this chapter, we review an array of non-neoplastic entities and orbital tumors, for which there exists a role for radiation, and the radiotherapeutic techniques and applications in their management. PMID:23989130

  10. Quality in radiation oncology

    SciTech Connect

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

    2007-05-15

    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.

  11. Radiation shielding composition

    DOEpatents

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

    1998-07-28

    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.

  12. TOPEX orbital radiation study

    NASA Technical Reports Server (NTRS)

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

    1984-01-01

    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.

  13. Handheld CZT radiation detector

    DOEpatents

    Murray, William S.; Butterfield, Kenneth B.; Baird, William

    2004-08-24

    A handheld CZT radiation detector having a CZT gamma-ray sensor, a multichannel analyzer, a fuzzy-logic component, and a display component is disclosed. The CZT gamma-ray sensor may be a coplanar grid CZT gamma-ray sensor, which provides high-quality gamma-ray analysis at a wide range of operating temperatures. The multichannel analyzer categorizes pulses produce by the CZT gamma-ray sensor into channels (discrete energy levels), resulting in pulse height data. The fuzzy-logic component analyzes the pulse height data and produces a ranked listing of radioisotopes. The fuzzy-logic component is flexible and well-suited to in-field analysis of radioisotopes. The display component may be a personal data assistant, which provides a user-friendly method of interacting with the detector. In addition, the radiation detector may be equipped with a neutron sensor to provide an enhanced mechanism of sensing radioactive materials.

  14. Relativistic coherent curvature radiation

    NASA Astrophysics Data System (ADS)

    Benford, G.; Buschauer, R.

    1983-02-01

    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.

  15. Radiation Environment Inside Spacecraft

    NASA Technical Reports Server (NTRS)

    O'Neill, Patrick

    2015-01-01

    Dr. Patrick O'Neill, NASA Johnson Space Center, will present a detailed description of the radiation environment inside spacecraft. The free space (outside) solar and galactic cosmic ray and trapped Van Allen belt proton spectra are significantly modified as these ions propagate through various thicknesses of spacecraft structure and shielding material. In addition to energy loss, secondary ions are created as the ions interact with the structure materials. Nuclear interaction codes (FLUKA, GEANT4, HZTRAN, MCNPX, CEM03, and PHITS) transport free space spectra through different thicknesses of various materials. These "inside" energy spectra are then converted to Linear Energy Transfer (LET) spectra and dose rate - that's what's needed by electronics systems designers. Model predictions are compared to radiation measurements made by instruments such as the Intra-Vehicular Charged Particle Directional Spectrometer (IV-CPDS) used inside the Space Station, Orion, and Space Shuttle.

  16. Biochemistry of ionizing radiation

    SciTech Connect

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

    1990-01-01

    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.

  17. Provisional standards of radiation safety during flights

    NASA Technical Reports Server (NTRS)

    1977-01-01

    Radiation effects during space flights are discussed in the context of the sources and dangers of such radiation and the radiobiological prerequisites for establishing safe levels of radiation dosage. Standard safe levels of radiation during space flight are established.

  18. The radiation hazard during space flights

    NASA Technical Reports Server (NTRS)

    Kovalev, Y. Y.; Kolomenskiy, A. V.; Smirennyy, L. N.; Petrov, V. M.

    1973-01-01

    Galactic cosmic radiation is described. Distinctive features of radiation effects in space flights are discussed and space radiation hazards are estimated. Measures to provide radiation safety during space flights are given. The need for safety standards is emphasized.

  19. RADIATION PERMIT APPLICATION Western Human Resources

    E-print Network

    Sinnamon, Gordon J.

    1 RADIATION PERMIT APPLICATION Western Human Resources Occupational Health & Safety Please complete the information and send to: Hoa Ly Radiation Safety Coordinator Occupational Health and Safety Room 4190, Support: ________________________ Fax: ___________________________________ Radiation Safety Training and Radiation Work Experience 1

  20. Questions to Ask about Radiation Safety

    MedlinePLUS

    ... Prostate Skin Upper GI Latest Research Find a Radiation Oncologist Last Name: Facility: City: State: Zip Code: ... ask about radiation safety Questions to ask about radiation safety Radiation is a safe, highly effective cancer ...

  1. Radiation in Yolo County

    NASA Astrophysics Data System (ADS)

    Dickie, H.; Colwell, K.

    2013-12-01

    In today's post-nuclear age, there are many man-made sources of radioactivity, in addition to the natural background we expect from cosmic and terrestrial origins. While all atoms possess unstable isotopes, there are few that are abundant enough, energetic enough, and have long enough half-lives to pose a signicant risk of ionizing radiation exposure. We hypothesize a decreasing relative radiation measurement (in detected counts per minute [CPM]) at nine locations that might pose occupational or environmental hazard: 1. A supermarket produce aisle (living tissue has high concentration of 40K) 2. A hospital (medical imaging uses X-rays and radioactive dyes) 3. The electronics section of a superstore (high voltage electronics have the potential to produce ionizing radiation) 4. An electrical transformer (similar reasons) 5. An antique store (some ceramics and glazes use radioisotopes that are now outlawed) 6. A gasoline pump (processing and terrestrial isotope contamination might leave a radioactive residue) 7. A fertilized eld (phosphate rock contains uranium and thorium, in addition to potassium) 8. A house (hopefully mild background, but potential radon contamination) 9. A school (should be radiologically neutral) We tested the hypothesis by measuring 100 minutes of counts on a self-assembled MightyOhmTM Geiger counter at each location. Our results show that contrary to the hypothesized ordering, the house was the most radiologically active. We present possible explanations for the observed radiation levels, as well as possible sources of measurement error, possible consequences of prolonged exposure to the measured levels, and suggestions for decreasing exposure and environmental impact.

  2. Radiation biology of mosquitoes

    PubMed Central

    Helinski, Michelle EH; Parker, Andrew G; Knols, Bart GJ

    2009-01-01

    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 stage was irradiated due to ease of handling compared to the adult stage. The dose-response curve between the induced sterility and log (dose) was shown to be sigmoid, and there was a marked species difference in radiation sensitivity. Mating competitiveness studies have generally been performed under laboratory conditions. The competitiveness of males irradiated at high doses was relatively poor, but with increasing ratios of sterile males, egg hatch could be lowered effectively. Males irradiated as pupae had a lower competitiveness compared to males irradiated as adults, but the use of partially-sterilizing doses has not been studied extensively. Methods to reduce somatic damage during the irradiation process as well as the use of other agents or techniques to induce sterility are discussed. It is concluded that the optimal radiation dose chosen for insects that are to be released during an SIT programme should ensure a balance between induced sterility of males and their field competitiveness, with competitiveness being determined under (semi-) field conditions. Self-contained 60Co research irradiators remain the most practical irradiators but these are likely to be replaced in the future by a new generation of high output X ray irradiators. PMID:19917076

  3. Supersymmetrization of radiation damping

    NASA Astrophysics Data System (ADS)

    Mendes, A. C. R.; Neves, C.; Oliveira, W.; Takakura, F. I.

    2005-10-01

    We construct a supersymmetrized version of the model to the radiation damping introduced by the present authors (Mendes, Neves, Oliveira and Takakura 2005 Preprint hep-th/0503135). We discuss its symmetries and the corresponding conserved Noether charges. It is shown that this supersymmetric version provides a supersymmetric generalization of the Galilei algebra of the model. We have shown that the supersymmetric action can be split into dynamically independent external and internal sectors.

  4. Ionizing radiation during pregnancy.

    PubMed Central

    Ratnapalan, Savithiri; Bona, Nicole; Koren, Gideon

    2003-01-01

    QUESTION: One of my patients had a computed tomography scan of her abdomen a week ago and has just found out she is 7 weeks pregnant. What should I tell her about the pregnancy and the risk to her fetus? ANSWER: Your patient is not at increased risk of miscarriage or major congenital fetal malformations due to radiation exposure. Her risk is similar to that of the general population (ie, 1% to 3%). PMID:12901480

  5. 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.

  6. Josephson-vortex Cherenkov radiation

    SciTech Connect

    Mints, R.G.; Snapiro, I.B. [School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel)] [School of Physics and Astronomy, Raymond and Beverly Sackler Faculty of Exact Sciences, Tel Aviv University, Tel Aviv 69978 (Israel)

    1995-10-01

    We predict the Josephson-vortex Cherenkov radiation of an electromagnetic wave. We treat a long one-dimensional Josephson junction. We consider the wavelength of the radiated electromagnetic wave to be much less than the Josephson penetration depth. We use for calculations the nonlocal Josephson electrodynamics. We find the expression for the radiated power and for the radiation friction force acting on a Josephson vortex and arising due to the Cherenkov radiation. We calculate the relation between the density of the bias current and the Josephson vortex velocity.

  7. Photon Clusters in Thermal Radiation

    E-print Network

    Aleksey Ilyin

    2014-10-30

    Within the framework of Bose-Einstein statistics, it is shown that the blackbody radiation, in addition to single photons, contains photon clusters, or coalescent photons. The probability to find a k-photon cluster versus radiation frequency and temperature is found, as well as the statistics of clusters. Spectra of photon-cluster radiation are calculated as functions of blackbody temperature. The Planck's radiation law is derived based on the existence of photon clusters. The possibility of experimental observation of photon clusters in thermal radiation is discussed.

  8. Radiation Protection in Canada

    PubMed Central

    Bird, P. M.

    1964-01-01

    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. PMID:14146856

  9. Fundamentals of Atmospheric Radiation

    NASA Astrophysics Data System (ADS)

    Bohren, Craig F.; Clothiaux, Eugene E.

    2006-02-01

    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.

  10. Intraocular radiation blocking

    SciTech Connect

    Finger, P.T.; Ho, T.K.; Fastenberg, D.M.; Hyman, R.A.; Stroh, E.M.; Packer, S.; Perry, H.D. (North Shore Univ. Hospital, Manhasset, NY (USA))

    1990-09-01

    Iodine-based liquid radiographic contrast agents were placed in normal and tumor-bearing (Greene strain) rabbit eyes to evaluate their ability to block iodine-125 radiation. This experiment required the procedures of tumor implantation, vitrectomy, air-fluid exchange, and 125I plaque and thermoluminescent dosimetry (TLD) chip implantation. The authors quantified the amount of radiation attenuation provided by intraocularly placed contrast agents with in vivo dosimetry. After intraocular insertion of a blocking agent or sham blocker (saline) insertion, episcleral 125I plaques were placed across the eye from episcleral TLD dosimeters. This showed that radiation attenuation occurred after blocker insertion compared with the saline controls. Then computed tomographic imaging techniques were used to describe the relatively rapid transit time of the aqueous-based iohexol compared with the slow transit time of the oil-like iophendylate. Lastly, seven nontumor-bearing eyes were primarily examined for blocking agent-related ocular toxicity. Although it was noted that iophendylate induced intraocular inflammation and retinal degeneration, all iohexol-treated eyes were similar to the control eyes at 7 and 31 days of follow-up. Although our study suggests that intraocular radiopaque materials can be used to shield normal ocular structures during 125I plaque irradiation, a mechanism to keep these materials from exiting the eye must be devised before clinical application.

  11. Radiation hardening of diagnostics

    SciTech Connect

    Siemon, R.E.

    1991-01-01

    The world fusion program has advanced to the stage where it is appropriate to construct a number of devices for the purpose of burning DT fuel. In these next-generation experiments, the expected flux and fluence of 14 MeV neutrons and associated gamma rays will pose a significant challenge to the operation and diagnostics of the fusion device. Radiation effects include structural damage to materials such as vacuum windows and seals, modifications to electrical properties such as electrical conductivity and dielectric strength and impaired optical properties such as reduced transparency and luminescence of windows and fiber optics during irradiation. In preparation for construction and operation of these new facilities, the fusion diagnostics community needs to work with materials scientists to develop a better understanding of radiation effects, and to undertake a testing program aimed at developing workable solutions for this multi-faceted problem. A unique facility to help in this regard is the Los Alamos Spallation Radiation Effects Facility, a neutron source located at the beam stop of the world's most powerful accelerator, the Los Alamos Meson Physics Facility (LAMPF). The LAMPF proton beam generates 10{sup 16} neutrons per second because of spallation'' reactions when the protons collide with the copper nuclei in the beam stop.

  12. Optical radiation and visual health

    SciTech Connect

    Waxler, M.; Hitchins, V.M.

    1986-01-01

    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.

  13. New Approaches to Radiation Protection

    PubMed Central

    Rosen, Eliot M.; Day, Regina; Singh, Vijay K.

    2015-01-01

    Radioprotectors are compounds that protect against radiation injury when given prior to radiation exposure. Mitigators can protect against radiation injury when given after exposure but before symptoms appear. Radioprotectors and mitigators can potentially improve the outcomes of radiotherapy for cancer treatment by allowing higher doses of radiation and/or reduced damage to normal tissues. Such compounds can also potentially counteract the effects of accidental exposure to radiation or deliberate exposure (e.g., nuclear reactor meltdown, dirty bomb, or nuclear bomb explosion); hence they are called radiation countermeasures. Here, we will review the general principles of radiation injury and protection and describe selected examples of radioprotectors/mitigators ranging from small-molecules to proteins to cell-based treatments. We will emphasize agents that are in more advanced stages of development. PMID:25653923

  14. Method for microbeam radiation therapy

    DOEpatents

    Slatkin, D.N.; Dilmanian, F.A.; Spanne, P.O.

    1994-08-16

    A method is disclosed 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. The dose is 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. No Drawings

  15. Method for microbeam radiation therapy

    DOEpatents

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

    1994-01-01

    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.

  16. Global aspects of radiation memory

    E-print Network

    J. Winicour

    2014-10-11

    Gravitational radiation has a memory effect represented by a net change in the relative positions of test particles. Both the linear and nonlinear sources proposed for this radiation memory are of the "electric" type, or E mode, as characterized by the even parity of the polarization pattern. Although "magnetic" type, or B mode, radiation memory is mathematically possible, no physically realistic source has been identified. There is an electromagnetic counterpart to radiation memory in which the velocity of charged particles obtain a net "kick". Again, the physically realistic sources of electromagnetic radiation memory that have been identified are of the electric type. In this paper, a global null cone description of the electromagnetic field is applied to establish the non-existence of B mode radiation memory and the non-existence of E mode radiation memory due to a bound charge distribution.

  17. Utrecht Radiative Transfer Courses

    NASA Astrophysics Data System (ADS)

    Rutten, R. J.

    2003-01-01

    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.

  18. Radiation Safety System for Stanford Synchrotron Radiation Laboratory

    SciTech Connect

    Liu, J

    2004-03-12

    Radiation Safety System (RSS) at the Stanford Synchrotron Radiation Laboratory is summarized and reviewed. The RSS, which is designed to protect people from prompt radiation hazards from accelerator operation, consists of the Access Control System (ACS) and the Beam Containment System (BCS). The ACS prevents people from being exposed to the lethal radiation level inside the shielding housing (called a PPS area at SLAC). The ACS for a PPS area consists of the shielding housing, beam inhibiting devices, and a standard entry module at each entrance. The BCS protects people from the prompt radiation hazards outside a PPS area under both normal and abnormal beam loss situations. The BCS consists of the active power (current/energy) limiting devices, beam stoppers, shielding, and an active radiation monitor system. The policies and practices in setting up the RSS at SLAC are illustrated.

  19. Structure in Radiating Shocks

    NASA Astrophysics Data System (ADS)

    Doss, Forrest

    2010-11-01

    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.

  20. Baryogenesis from Hawking Radiation

    E-print Network

    Anson Hook

    2015-01-05

    We show that in the presence of a chemical potential, black hole evaporation generates baryon number. If the inflaton or Ricci scalar is derivatively coupled to the B-L current, the expansion of the universe acts as a chemical potential and splits the energy levels of particles and their anti-particles. The asymmetric Hawking radiation of primordial black holes can thus be used to generate a B-L asymmetry. If dark matter is produced by the same mechanism, the coincidence between the mass density of visible and dark matter can be naturally explained.

  1. Protection from Space Radiation

    NASA Technical Reports Server (NTRS)

    Tripathi, R. K.; Wilson, J. W.; Shinn, J. L.; Singleterry, R. C.; Clowdsley, M. S.; Cucinotta, F. A.; Badhwar, G. D.; Kim, M. Y.; Badavi, F. F.; Heinbockel, J. H.

    2000-01-01

    The exposures anticipated for our astronauts in the anticipated Human Exploration and Development of Space (HEDS) will be significantly higher (both annual and carrier) than any other occupational group. In addition, the exposures in deep space result largely from the Galactic Cosmic Rays (GCR) for which there is as yet little experience. Some evidence exists indicating that conventional linear energy transfer (LET) defined protection quantities (quality factors) may not be appropriate [1,2]. The purpose of this presentation is to evaluate our current understanding of radiation protection with laboratory and flight experimental data and to discuss recent improvements in interaction models and transport methods.

  2. Radiation Field on Superspace

    E-print Network

    P. F. Gonzalez-Diaz

    1994-03-18

    We study the dynamics of multiwormhole configurations within the framework of the Euclidean Polyakov approach to string theory, incorporating a modification to the Hamiltonian which makes it impossible to interpret the Coleman Alpha parameters of the effective interactions as a quantum field on superspace, reducible to an infinite tower of fields on space-time. We obtain a Planckian probability measure for the Alphas that allows $\\frac{1}{2}\\alpha^{2}$ to be interpreted as the energy of the quanta of a radiation field on superspace whose values may still fix the coupling constants.

  3. Radiation imaging apparatus

    DOEpatents

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

    1983-01-01

    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.

  4. Radiation imaging apparatus

    DOEpatents

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

    1983-07-26

    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.

  5. Radiative lifetimes of Tb

    SciTech Connect

    Den Hartog, E. A.; Fedchak, J. A.; Lawler, J. E.

    2001-06-01

    Radiative lifetimes measured by time-resolved laser-induced fluorescence are reported for 40 odd-parity levels and 36 even-parity levels of singly ionized terbium. The odd-parity levels range in energy from 29000 to 40000 cm{minus}1 and those of even-parity from 21000 to 37000 cm{minus}1. These lifetimes, with one exception, are accurate to {+-}5%. They will provide an absolute scale for accurate atomic-transition probabilities in Tb II (the second spectrum of terbium). {copyright} 2001 Optical Society of America

  6. LDEF satellite radiation study

    NASA Technical Reports Server (NTRS)

    Armstrong, T. W.; Colborn, B. L.

    1994-01-01

    Some early results are summarized from a program under way to utilize LDEF satellite data for evaluating and improving current models of the space radiation environment in low earth orbit. Reported here are predictions and comparisons with some of the LDEF dose and induced radioactivity data, which are used to check the accuracy of current models describing the magnitude and directionality of the trapped proton environment. Preliminary findings are that the environment models underestimate both dose and activation from trapped protons by a factor of about two, and the observed anisotropy is higher than predicted.

  7. Standard climate models radiation codes underestimate black carbon radiative forcing

    NASA Astrophysics Data System (ADS)

    Myhre, G.; Samset, B. H.

    2015-03-01

    Radiative forcing (RF) of black carbon (BC) in the atmosphere is estimated using radiative transfer codes of various complexities. Here we show that the two-stream radiative transfer codes used most in climate models give too strong forward scattering, leading to enhanced absorption at the surface and too weak absorption by BC in the atmosphere. Such calculations are found to underestimate the positive RF of BC by 10% for global mean, all sky conditions, relative to the more sophisticated multi-stream models. The underestimation occurs primarily for low surface albedo, even though BC is more efficient for absorption of solar radiation over high surface albedo.

  8. Standard climate models radiation codes underestimate black carbon radiative forcing

    NASA Astrophysics Data System (ADS)

    Myhre, G.; Samset, B. H.

    2014-10-01

    Radiative forcing (RF) of black carbon (BC) in the atmosphere is estimated using radiative transfer codes of various complexities. Here we show that the 2-stream radiative transfer codes used most in climate models give too strong forward scattering, leading to enhanced absorption at the surface and too weak absorption by BC. Such calculations are found to underestimate RF by 10% for global mean, all sky conditions, relative to the more sophisticated multi-stream models. The underestimation occurs primarily for low surface albedo, even though BC is more efficient for absorption of solar radiation at high surface albedo.

  9. Effect of lateral radiative losses on radiative shock propagation

    NASA Astrophysics Data System (ADS)

    Busquet, M.; Audit, E.; González, M.; Stehlé, C.; Thais, F.; Acef, O.; Bauduin, D.; Barroso, P.; Rus, B.; Kozlova, M.; Polan, J.; Mocek, T.

    2007-05-01

    Experimental and numerical studies of radiative shocks, of interest as scaled astrophysical objects, have been performed. Experiments were conducted at the PALS facility in Prague with a xenon filled mini-shock tube using a laser accelerated plastic pusher. Numerical simulations of the hydrodynamics including radiation effects have been performed with the 3D code HERACLES. Measurements have been made of the electronic density of the shocked gas and of the time history of the position of the radiative precursor. Simulations and experimental results show good agreement when lateral radiative losses are taken into account, including a wall albedo of 40%.

  10. Children, CT Scan and Radiation.

    PubMed

    Bajoghli, Morteza; Bajoghli, Farshad; Tayari, Nazila; Rouzbahani, Reza

    2010-01-01

    Children are more sensitive to radiation than adults. Computerized tomography (CT) consists of 25 % of all medical imaging. It was estimated that more than 2% of all carcinomas in the USA are due to CT scans. There is an ongoing focus on the reduction of CT scan radiation dose. Awareness about risk-benefits of CT has increased. Reduction of radiological exam is an important issue because the accumulation effects of radiation can be hazardous. In addition, proper protocol should be followed for diagnostic procedures of ionization radiation and computerized tomography. Effective radiation dose should range from 0.8 to 10.5 millisievert. The same protocol should be followed in different hospitals as well. Basic principles of radiation protection should be monitored. As much as possible, both technician and radiologist must be present during computerized tomography for children, and MRI and ultrasound should be replaced if possible. PMID:21566776

  11. Gravitational scattering of electromagnetic radiation

    NASA Technical Reports Server (NTRS)

    Brooker, J. T.; Janis, A. I.

    1980-01-01

    The scattering of electromagnetic radiation by linearized gravitational fields is studied to second order in a perturbation expansion. The incoming electromagnetic radiation can be of arbitrary multipole structure, and the gravitational fields are also taken to be advanced fields of arbitrary multipole structure. All electromagnetic multipole radiation is found to be scattered by gravitational monopole and time-varying dipole fields. No case has been found, however, in which any electromagnetic multipole radiation is scattered by gravitational fields of quadrupole or higher-order multipole structure. This lack of scattering is established for infinite classes of special cases, and is conjectured to hold in general. The results of the scattering analysis are applied to the case of electromagnetic radiation scattered by a moving mass. It is shown how the mass and velocity may be determined by a knowledge of the incident and scattered radiation.

  12. RADIATIVE RAYLEIGH-TAYLOR INSTABILITIES

    SciTech Connect

    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

    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.

  13. Genetic susceptibility to radiation

    NASA Astrophysics Data System (ADS)

    Hall, E. J.; Brenner, D. J.; Worgul, B.; Smilenov, L.

    In the context of space radiation, it is important to know whether the human population includes genetically predisposed radiosensitive subsets. One possibility is that haploinsufficiency for ATM confers radiosensitivity, and this defect involves 1 3% of the population. Using knock-out mice we chose to study cataractogenesis in the lens and oncogenic transformation in mouse embryo fibroblasts to assay for effects of ATM deficiency. Radiation induced cataracts appeared earlier in the heterozygous versus wild-type animals following exposure to either gamma rays or 1 GeV/nucleon iron ions. In addition, it was found that embryo fibroblasts of Atm heterozygotes showed an increased incidence of oncogenic transformation compared with their normal litter-matched counterparts. From these data we suggest that Ataxia Telangiectasia heterozygotes could indeed represent a societally significant radiosensitive subpopulation. Knock-out mice are now available for other genes including BRCA1 and 2, and Mrad9. An exciting possibility is the creation of double heterozygotes for pairs of mutated genes that function in the same signal transduction pathway, and consequently confer even greater radiosensitivity.

  14. Split supersymmetry radiates flavor

    NASA Astrophysics Data System (ADS)

    Baumgart, Matthew; Stolarski, Daniel; Zorawski, Thomas

    2014-09-01

    Radiative flavor models where the hierarchies of Standard Model (SM) fermion masses and mixings are explained via loop corrections are elegant ways to solve the SM flavor puzzle. Here we build such a model in the context of mini-split supersymmetry (SUSY) where both flavor and SUSY breaking occur at a scale of 1000 TeV. This model is consistent with the observed Higgs mass, unification, and dark matter as a weakly interacting massive particle. The high scale allows large flavor mixing among the sfermions, which provides part of the mechanism for radiative flavor generation. In the deep UV, all flavors are treated democratically, but at the SUSY-breaking scale, the third, second, and first generation Yukawa couplings are generated at tree level, one loop, and two loops, respectively. Save for one, all the dimensionless parameters in the theory are O(1), with the exception being a modest and technically natural tuning that explains both the smallness of the bottom Yukawa coupling and the largeness of the Cabibbo angle.

  15. Biologically efficient solar radiation

    PubMed Central

    Grigalavicius, Mantas; Juzeniene, Asta; Baturaite, Zivile; Dahlback, Arne; Moan, Johan

    2013-01-01

    Solar ultraviolet (UV) radiation is the main source of vitamin D production and is also the most important environmental risk factor for cutaneous malignant melanoma (CMM) development. In the present study the relationships between daily or seasonal UV radiation doses and vitamin D status, dietary vitamin D intake and CMM incidence rates at different geographical latitudes were investigated. North-South gradients of 25-hydroxyvitamin D (25(OH)D) generation and CMM induction were calculated, based on known action spectra, and compared with measured vitamin D levels and incidence rates of CMM. The relative roles of UVA and UVB in CMM induction are discussed. Latitudinal dependencies of serum 25(OH)D levels and CMM incidence rates can only partly be explained by ambient UV doses. The UV sensitivity is different among populations with different skin color. This is well known for CMM, but seems also to be true for vitamin D status. The fact that UV-induced vitamin D may reduce the risk of CMM complicates the discussion. To some extent high dietary vitamin D intake seems to compensate low UV doses. PMID:24494048

  16. Ultraviolet radiation and cyanobacteria.

    PubMed

    Rastogi, Rajesh Prasad; Sinha, Rajeshwar P; Moh, Sang Hyun; Lee, Taek Kyun; Kottuparambil, Sreejith; Kim, Youn-Jung; Rhee, Jae-Sung; Choi, Eun-Mi; Brown, Murray T; Häder, Donat-Peter; Han, Taejun

    2014-12-01

    Cyanobacteria are the dominant photosynthetic prokaryotes from an ecological, economical, or evolutionary perspective, and depend on solar energy to conduct their normal life processes. However, the marked increase in solar ultraviolet radiation (UVR) caused by the continuous depletion of the stratospheric ozone shield has fueled serious concerns about the ecological consequences for all living organisms, including cyanobacteria. UV-B radiation can damage cellular DNA and several physiological and biochemical processes in cyanobacterial cells, either directly, through its interaction with certain biomolecules that absorb in the UV range, or indirectly, with the oxidative stress exerted by reactive oxygen species. However, cyanobacteria have a long history of survival on Earth, and they predate the existence of the present ozone shield. To withstand the detrimental effects of solar UVR, these prokaryotes have evolved several lines of defense and various tolerance mechanisms, including avoidance, antioxidant production, DNA repair, protein resynthesis, programmed cell death, and the synthesis of UV-absorbing/screening compounds, such as mycosporine-like amino acids (MAAs) and scytonemin. This study critically reviews the current information on the effects of UVR on several physiological and biochemical processes of cyanobacteria and the various tolerance mechanisms they have developed. Genomic insights into the biosynthesis of MAAs and scytonemin and recent advances in our understanding of the roles of exopolysaccharides and heat shock proteins in photoprotection are also discussed. PMID:25463663

  17. Diffuse gamma radiation

    NASA Technical Reports Server (NTRS)

    Fichtel, C. E.; Simpson, G. A.; Thompson, D. J.

    1977-01-01

    An examination of the intensity, energy spectrum, and spatial distribution of the diffuse gamma-radiation observed by SAS-2 satellite away from the galactic plane in the energy range above 35 MeV has shown that it consists of two components. One component is generally correlated with galactic latitudes, the atomic hydrogen column density was deduced from 21 cm measurements, and the continuum radio emission, believed to be synchrotron emission. It has an energy spectrum similar to that in the plane and joins smoothly to the intense radiation from the plane. It is therefore presumed to be of galactic origin. The other component is apparently isotropic, at least on a coarse scale, and has a steep energy spectrum. No evidence is found for a cosmic ray halo surrounding the galaxy in the shape of a sphere or oblate spheroid with galactic dimensions. Constraints for a halo model with significantly larger dimensions are set on the basis of an upper limit to the gamma-ray anisotropy.

  18. Space radiation studies

    NASA Technical Reports Server (NTRS)

    1989-01-01

    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.

  19. Imaging with terahertz radiation

    NASA Astrophysics Data System (ADS)

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

    2007-08-01

    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.

  20. Chandra Radiation Environment Modeling

    NASA Technical Reports Server (NTRS)

    Minow, Joseph I.; Blackwell, W. C.

    2003-01-01

    CRMFLX (Chandra Radiation Model of ion FluX) is a radiation environment risk mitigation tool for use as a decision aid in planning the operations times for Chandra's Advanced CCD Imaging Spectrometer (ACIS) detector. The accurate prediction of the proton flux environment with energies of 100 - 200 keV is needed in order to protect the ACIS detector against proton degradation. Unfortunately, protons of this energy are abundant in the region of space Chandra must operate, and on-board particle detectors do not measure proton flux levels of the required energy range. This presentation will describe the plasma environment data analysis and modeling basis of the CRMFLX engineering environment model developed to predict the proton flux in the solar wind, magnetosheath, and magnetosphere phenomenological regions of geospace. The recently released CRMFLX Version 2 implementation includes an algorithm that propagates flux from an observation location to other regions of the magnetosphere based on convective ExB and VB-curvature particle drift motions. This technique has the advantage of more completely filling out the database and makes maximum use of limited data obtained during high Kp periods or in areas of the magnetosphere with poor satellite flux measurement coverage.

  1. Solar Radiation Storm

    NSDL National Science Digital Library

    Payne, Laura X.

    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.

  2. Management of radiation ulcers

    SciTech Connect

    Shack, R.B.

    1982-12-01

    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.

  3. Radiation Embrittlement Archive Project

    SciTech Connect

    Klasky, Hilda B [ORNL] [ORNL; Bass, Bennett Richard [ORNL] [ORNL; Williams, Paul T [ORNL] [ORNL; Phillips, Rick [ORNL] [ORNL; Erickson, Marjorie A [ORNL] [ORNL; Kirk, Mark T [ORNL] [ORNL; Stevens, Gary L [ORNL] [ORNL

    2013-01-01

    The Radiation Embrittlement Archive Project (REAP), which is being conducted by the Probabilistic Integrity Safety Assessment (PISA) Program at Oak Ridge National Laboratory under funding from the U.S. Nuclear Regulatory Commission s (NRC) Office of Nuclear Regulatory Research, aims to provide an archival source of information about the effect of neutron radiation on the properties of reactor pressure vessel (RPV) steels. Specifically, this project is an effort to create an Internet-accessible RPV steel embrittlement database. The project s website, https://reap.ornl.gov, provides information in two forms: (1) a document archive with surveillance capsule(s) reports and related technical reports, in PDF format, for the 104 commercial nuclear power plants (NPPs) in the United States, with similar reports from other countries; and (2) a relational database archive with detailed information extracted from the reports. The REAP project focuses on data collected from surveillance capsule programs for light-water moderated, nuclear power reactor vessels operated in the United States, including data on Charpy V-notch energy testing results, tensile properties, composition, exposure temperatures, neutron flux (rate of irradiation damage), and fluence, (Fast Neutron Fluence a cumulative measure of irradiation for E>1 MeV). Additionally, REAP contains data from surveillance programs conducted in other countries. REAP is presently being extended to focus on embrittlement data analysis, as well. This paper summarizes the current status of the REAP database and highlights opportunities to access the data and to participate in the project.

  4. Deterministic methods in radiation transport

    SciTech Connect

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

    1992-06-01

    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.

  5. Radiation efficiency of damped plates.

    PubMed

    Kou, Yiwei; Liu, Bilong; Tian, Jing

    2015-02-01

    The radiation efficiency of damped plates is discussed in this letter. Below the critical frequency of a plate, numerical results show that the radiation efficiency is much influenced by damping. Some modifications of the classical formulas given by Cremer for an infinite plate and Leppington for a finite rectangular plate are proposed to include the influence of the damping on the radiation efficiency. PMID:25698034

  6. RSSC RADIATION DETECTORS & SURVEY INSTRUMENTS 8/99 4-1 RADIATION DETECTORS AND SURVEY INSTRUMENTS

    E-print Network

    Slatton, Clint

    RSSC RADIATION DETECTORS & SURVEY INSTRUMENTS 8/99 4-1 CHAPTER 4 RADIATION DETECTORS AND SURVEY........................................................................................................... 4-3 II. Use of Radiation Survey Instruments

  7. DNA fragmentation pattern in human fibroblasts after irradiation with iron ions

    NASA Astrophysics Data System (ADS)

    Campa, Alessandro

    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/µm and 442 keV/µm, 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).

  8. 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.

  9. Therapeutic Applications of Ionizing Radiations

    NASA Astrophysics Data System (ADS)

    Sánchez-Santos, María Elena

    The aim of radiation therapy is to deliver a precisely measured dose of radiation to a defined tumour volume with minimal damage to the surrounding healthy tissue, resulting in the eradication of the tumour, a higher quality of life with palliation of symptoms of the disease, and the prolongation of survival at competitive cost. Together with surgery and pharmacology, radiotherapy is presently one of the most important therapeutical weapons against cancer. This chapter provides an overview of the clinical use of radiation, with emphasis on the optimisation of treatment planning and delivery, and a top level summary of state-of-the-art techniques in radiation therapy.

  10. Ionizing radiation promotes protozoan reproduction

    SciTech Connect

    Luckey, T.D.

    1986-11-01

    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.

  11. Enhanced radiation resistant fiber optics

    DOEpatents

    Lyons, P.B.; Looney, L.D.

    1993-11-30

    A process for producing an optical fiber having enhanced radiation resistance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation. 4 figures.

  12. Enhanced radiation resistant fiber optics

    DOEpatents

    Lyons, Peter B. (Los Alamos, NM); Looney, Larry D. (Los Alamos, NM)

    1993-01-01

    A process for producing an optical fiber having enhanced radiation resitance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation.

  13. Electromagnetic radiation by gravitating bodies

    E-print Network

    Iwo Bialynicki-Birula; Zofia Bialynicka-Birula

    2008-05-06

    Gravitating bodies in motion, regardless of their constitution, always produce electromagnetic radiation in the form of photon pairs. This phenomenon is an analog of the radiation caused by the motion of dielectric (or magnetic) bodies. It is a member of a wide class of phenomena named dynamical Casimir effects, and it may be viewed as the squeezing of the electromagnetic vacuum. Production of photon pairs is a purely quantum-mechanical effect. Unfortunately, as we show, the emitted radiation is extremely weak as compared to radiation produced by other mechanisms.

  14. ANALYSISOFA MAGNETICALLYTUNABLE PATCH RADIATOR INCLUDING

    E-print Network

    Bornemann, Jens

    mono- lithic integrationof such substrates [l], microstripradiators on ferrite substrates [2], [3 and substrate losses in the analysis of magnetically tunable patch radiators on ferrite substrates. A modified

  15. Inverse problem for Bremsstrahlung radiation

    SciTech Connect

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

    1991-10-01

    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.

  16. Radiation thermometry: The measurement problem

    NASA Technical Reports Server (NTRS)

    Nutter, G. D.

    1988-01-01

    An overview of the theory and techniques of radiometric thermometry is presented. The characteristics of thermal radiators (targets) are discussed along with surface roughness and oxidation effects, fresnel reflection and subsurface effects in dielectrics. The effects of the optical medium between the radiating target and the radiation thermometer are characterized including atmospheric effects, ambient temperature and dust environment effects and the influence of measurement windows. The optical and photodetection components of radiation thermometers are described and techniques for the correction of emissivity effects are addressed.

  17. Space Radiation and Bone Loss

    PubMed Central

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

    2011-01-01

    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

  18. Epidemiology of accidental radiation exposures.

    PubMed Central

    Cardis, E

    1996-01-01

    Much of the information on the health effects of radiation exposure available to date comes from long-term studies of the atomic bombings in Hiroshima and Nagasaki. Accidental exposures, such as those resulting from the Chernobyl and Kyshtym accidents, have as yet provided little information concerning health effects of ionizing radiation. This paper will present the current state of our knowledge concerning radiation effects, review major large-scale accidental radiation exposures, and discuss information that could be obtained from studies of accidental exposures and the types of studies that are needed. PMID:8781398

  19. THERMAL RADIATION The type of electromagnetic radiation that is pertinentThe type of electromagnetic radiation that is pertinent

    E-print Network

    Kostic, Milivoje M.

    THERMAL RADIATION The type of electromagnetic radiation that is pertinentThe type of electromagnetic radiation that is pertinent to heat transfer is the thermal radiation emitted as a result of the strength of these activities at the microscopic level, and the rate of thermal radiation emission increases

  20. RADIATION SAFETY COMMITTEE The Radiation Safety Committee shall advise the Provost on all policy matters relating to radiation safety;

    E-print Network

    Sze, Lawrence

    RADIATION SAFETY COMMITTEE Functions The Radiation Safety Committee shall advise the Provost on all policy matters relating to radiation safety; formulate campus radiation safety policies in compliance the Risk Manager) monitor the performance of the Radiation Safety Officer as it relates to implementation

  1. Theoretical studies of sonoluminescence radiation: Radiative transfer and parametric dependence

    Microsoft Academic Search

    L. Kondic; Joel I. Gersten; Chi Yuan

    1995-01-01

    We present results for sonoluminescent (SL) radiation from a strongly modulated air bubble in water. The SL pulse is due to high temperatures in the bubble that are produced by the collapse of a shock wave. The dependence of SL radiation on acoustic pressure and initial bubble size is discussed, as well as the inclusion of various mechanical energy loss

  2. Efficacy of radiation countermeasures depends on radiation quality.

    PubMed

    Cary, Lynnette H; Ngudiankama, Barbara F; Salber, Rudolph E; Ledney, G David; Whitnall, Mark H

    2012-05-01

    The detonation of a nuclear weapon or a nuclear accident represent possible events with significant exposure to mixed neutron/?-radiation fields. Although radiation countermeasures generally have been studied in subjects exposed to pure photons (? or X rays), the mechanisms of injury of these low linear energy transfer (LET) radiations are different from those of high-LET radiation such as neutrons, and these differences may affect countermeasure efficacy. We compared 30-day survival in mice after varying doses of pure ? and mixed neutron/? (mixed field) radiation (MF, Dn/Dt = 0.65), and also examined peripheral blood cells, bone marrow cell reconstitution, and cytokine expression. Mixed-field-irradiated mice displayed prolonged defects in T-cell populations compared to mice irradiated with pure ? photons. In mouse survival assays, the growth factor granulocyte colony-stimulating factor (G-CSF) was effective as a (post-irradiation) mitigator against both ?-photons and mixed-field radiation, while the thrombopoietin (TPO) mimetic ALXN4100TPO was effective only against ? irradiation. The results indicate that radiation countermeasures should be tested against radiation qualities appropriate for specific scenarios before inclusion in response plans. PMID:22468705

  3. Slope effects on shortwave radiation components and net radiation

    NASA Technical Reports Server (NTRS)

    Walter-Shea, Elizabeth A.; Blad, Blaine L.; Hays, Cynthia J.; Mesarch, Mark A.

    1992-01-01

    The main objective of the International Satellite Land Surface Climatology Project (ISLSCP) has been stated as 'the development of techniques that may be applied to satellite observations of the radiation reflected and emitted from the Earth to yield quantitative information concerning land surface climatological conditions.' The major field study, FIFE (the First ISLSCP Field Experiment), was conducted in 1978-89 to accomplish this objective. Four intensive field campaigns (IFC's) were carried out in 1987 and one in 1989. Factors contributing to observed reflected radiation from the FIFE site must be understood before the radiation observed by satellites can be used to quantify surface processes. Analysis since our last report has focused on slope effects on incoming and outgoing shortwave radiation and net radiation from data collected in 1989.

  4. RADIATION ASSOCIATED BRAINSTEM INJURY

    PubMed Central

    Mayo, Charles; Yorke, Ellen; Merchant, Thomas E.

    2010-01-01

    Publications relating brainstem radiation toxicity to quantitative dose and dose–volume measures derived from three-dimensional treatment planning were reviewed. Despite the clinical importance of brainstem toxicity, most studies reporting brainstem effects after irradiation have fewer than 100 patients. There is limited evidence relating toxicity to small volumes receiving doses above 60–64 Gy using conventional fractionation and no definitive criteria regarding more subtle dose–volume effects or effects after hypofractionated treatment. On the basis of the available data, the entire brainstem may be treated to 54 Gy using conventional fractionation using photons with limited risk of severe or permanent neurological effects. Smaller volumes of the brainstem (1–10 mL) may be irradiated to maximum doses of 59 Gy for dose fractions ?2 Gy; however, the risk appears to increase markedly at doses >64 Gy. PMID:20171516

  5. The IRAS radiation environment

    NASA Technical Reports Server (NTRS)

    Stassinopoulos, E. G.

    1978-01-01

    Orbital flux integration for three selected mission altitudes and geographic instantaneous flux-mapping for nominal flight-path altitude were used to determine the external charged particle radiation predicted for the Infrared Astronomy Satellite. A current field model was used for magnetic field definitions for three nominal circular trajectories and for the geographic mapping positions. Innovative analysis features introduced include (1) positional fluxes as a function of time and energy for the most severe pass through the South Atlantic Anomaly; (2) total positional doses as a function of time and shield thickness; (3) comparison mapping fluxes for ratios of positional intensities to orbit integrated averages; and (4) statistical exposure-time history of a trajectory as a function of energy indicating, in percent of total mission duration, the time intervals over which the instantaneous fluxes would exceed the orbit integrated averages. Results are presented in tables and graphs.

  6. Martian atmospheric radiation budget

    NASA Technical Reports Server (NTRS)

    Lindner, Bernhard Lee

    1994-01-01

    A computer model is used to study the radiative transfer of the martian winter-polar atmosphere. Solar heating at winter-polar latitudes is provided predominately by dust. For normal, low-dust conditions, CO2 provides almost as much heating as dust. Most heating by CO2 in the winter polar atmosphere is provided by the 2.7 micron band between 10 km and 30 km altitude, and by the 2.0 micron band below 10 km. The weak 1.3 micron band provides some significant heating near the surface. The minor CO2 bands at 1.4, 1.6, 4.8 and 5.2 micron are all optically thin, and produce negligible heating. O3 provides less than 10 percent of the total heating. Atmospheric cooling is predominantly thermal emission by dust, although CO2 15 micron band emission is important above 20 km altitude.

  7. Radiation and photochemistry section

    SciTech Connect

    Not Available

    1991-01-01

    The highlights of this past year in the Radiation and Photochemistry Section at Argonne include: (1) picosecond optical studies of radical cations and excited states produced in hydrocarbon radiolysis provided the first kinetic measurements of ion transformation and production of triplet and singlet excited states by ion recombination. (2) studies of radical cations of alkyl-substituted amines and sulfides provided insights into ion-molecule reactions of radical cations in the condensed phase. (3) studies of the behavior of strained alkane radical cations, such as cubane {sup +}{center dot}, revealed new rearrangements and remarkable, medium-dependent differences in their structures. (4) H{center dot}atom reactions yielding e{sub aq}{sup {minus}} provided the first reliable measurements of hydrated-electron enthalpy and entropy and forced the revision of some previous thinking about the driving force in {sub aq}{sup {minus}} reactions.

  8. Radiations from Radioactive Substances

    NASA Astrophysics Data System (ADS)

    Rutherford, Ernest; Chadwick, James; Drummond Ellis, Charles

    2010-06-01

    Preface; 1. Radioactive transformations; 2. The alpha rays; 3. Absorption of the alpha rays; 4. Some properties of the alpha particle; 5. Theories of absorption of alpha rays; 6. Secondary effects produced by alpha rays; 7. General properties of the radiations; 8. The scattering of alpha and beta particles; 9. The collisions of alpha particles with light atoms; 10. The artificial disintegration of the light elements; 11. The radioactive nuclei; 12. Beta ray and gamma ray spectra; 13. The disintegration electrons; 14. The passage of beta particles through matter; 15. The scattering and absorption of gamma rays; 16. Intensity problems connected with the emission of gamma rays; 17. Atomic nuclei; 18. Miscellaneous; Appendix; Indexes.

  9. [Radiation Tolerant Electronics

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Research work in the providing radiation tolerant electronics to NASA and the commercial sector is reported herein. There are four major sections to this report: (1) Special purpose VLSI technology section discusses the status of the VLSI projects as well as the new background technologies that have been developed; (2) Lossless data compression results provide the background and direction of new data compression pursued under this grant; (3) Commercial technology transfer presents an itemization of the commercial technology transfer; and (4) Delivery of VLSI to the Government is a solution and progress report that shows how the Government and Government contractors are gaining access to the technology that has been developed by the MRC.

  10. Sonoluminescence and Vacuum Radiation

    NASA Astrophysics Data System (ADS)

    Melunis, Justin; Flores, Eduardo

    2012-02-01

    Sonoluminescence is the generation of light from sound. Our goal is to understand why a bubble trapped in water could generate light from sound. In our work we investigate the contribution of the dynamical Casimir effect to this phenomenon. In previous work researchers have approach this problem as a semi static Casimir effect and have not been able to show a significant contribution of the Casimir effect to sonoluminescence. In our approach, we treat the surface of the bubble as a highly reflecting surface, thus, the electric field of the zero-point modes at the surface is zero. Thus, when the bubble collapses the zero-point modes inside and outside are disturbed. Since the dynamics of zero-point mode fields obey Maxwell equations we can simulate their dynamics using programs like Mathematica. We study the radiation of the excited zero-point mode field.

  11. Atmospheric Processes: Radiation

    NSDL National Science Digital Library

    In this activity, students investigate how different surfaces absorb heat and apply their experience with the surfaces to interpret real-world situations. From this information, they come to understand that the physical characteristics of a surface have a powerful effect on the way that surface absorbs and releases heat from the sun and that radiation of heat occurs without the involvement of a physical object. The student guide provides an overall description of the activity, a list of materials, the procedure, and observations and questions. The instructor guide contains detailed background material, learning goals, alignment to national standards, grade level/time, details on materials and preparation, procedure, assessment ideas, and modifications for alternative learners.

  12. Clinical radiation nephropathy

    SciTech Connect

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

    1995-03-30

    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.

  13. Microanalysis using synchrotron radiation

    NASA Astrophysics Data System (ADS)

    Kwiatek, Wojciech M.; Cichocki, Tadeusz; Galka, Marek; Paluszkiewicz, Czeslawa

    1992-05-01

    The SRIXE (synchrotron radiation induced X-ray emission) technique has been applied for several years in different fields of science. Since it has a number of useful advantages [1] it has been applied to microanalysis of thin tissue sections in order to investigate the trace element distribution in normal and cancerous kidneys. All the samples were surgically obtained in the Clinic of Urology at the Academy of Medicine in Cracow, Poland and were investigated in Hasylab at DESY, Hamburg, Germany with the synchrotron beam of 70 ?m × 100 ?m. Although only a few samples were measured so far, the results obtained seem to be promising. Enhanced trace element concentrations in cancerous parts of kidneys have been observed.

  14. Nanoscintillators for radiation detection

    NASA Astrophysics Data System (ADS)

    Hall, Ryan Gregory

    In the search for faster, more effective methods for detection of and protection against radiological weapons, advances in materials for radiation detection are a critical component of any successful strategy. This work focuses on producing inexpensive, but highly sensitive, nanoparticle alternatives to existing single-crystal installations. Attention is given to particular types of promising inorganic scintillators: LaF3, yttrium-aluminum-garnet (YAG), and SrF2, each one an inorganic host doped with additional elements that encourage luminescent decay and increase effective Z-value. I examine the possible routes to synthesize these compounds, and the difficulties and benefits of each method. After synthesizing these materials, testing was performed to determine comparative performance against each other and commercial solutions, identify structural and compositional characteristics, and explore routes for fixing the scintillators into a detector assembly. The unifying goal is to develop a scintillating material suitable for consistent dosimetry and radio-isotope identification applications.

  15. Conduction, Convection and Radiation

    NSDL National Science Digital Library

    Engineering K-PhD Program,

    With the help of simple, teacher-led demonstration activities, students learn the basic concepts of heat transfer by means of conduction, convection, and radiation. Students then apply these concepts as they work in teams to solve two problems. One problem requires that they maintain the warm temperature of one soda can filled with water at approximately body temperature, and the other problem is to cause an identical soda can of warm water to cool as much as possible during the same thirty-minute time interval. Students design their solutions using only common, everyday materials. They record the water temperatures in their two soda cans every five minutes, and prepare line graphs in order to visually compare their results to the temperature of an unaltered control can of water.

  16. Earth Radiation Budget Science, 1978. [conferences

    NASA Technical Reports Server (NTRS)

    1978-01-01

    An earth radiation budget satellite system planned in order to understand climate on various temporal and spatial scales is considered. Topics discussed include: climate modeling, climate diagnostics, radiation modeling, radiation variability and correlation studies, cloudiness and the radiation budget, and radiation budget and related measurements in 1985 and beyond.

  17. Radiation Safety Edward O'Connell

    E-print Network

    Radiation Safety Edward O'Connell Radiation Safety Officer Stony Brook University New York #12;STONY BROOK UNIVERSITY & U. HOSPITAL MEDICAL CENTER #12;Why Radiation Safety · Working with radioactive/Bureau of Environmental Radiation Protection (BERP) · Regulatory Compliance ­ State Sanitary 16 · Required Radiation

  18. Biology relevant to space radiation

    SciTech Connect

    Fry, R.J.M.

    1996-08-01

    The biological effects of the radiations to which mankind on earth are exposed are becoming known with an increasing degree of detail. This knowledge is the basis of the estimates of risk that, in turn, fosters a comprehensive and evolving radiation protection system. The substantial body of information has been, and is being, applied to questions about the biological effects of radiation is space and the associated risk estimates. The purpose of this paper is not to recount all the biological effect of radiation but to concentrate on those that may occur as a result from exposure to the radiations encountered in space. In general, the biological effects of radiation in space are the same as those on earth. However, the evidence that the effects on certain tissues by the heaviest-charged particles can be interpreted on the basis of our knowledge about other high-LET radiation is equivocal. This specific question will be discussed in greater detail later. It is important to point out the that there are only limited data about the effects on humans of two components of the radiations in space, namely protons and heavy ions. Thus predictions of effects on space crews are based on experimental systems exposed on earth at rates and fluences that are higher than those in space and one the effects of gamma or x rays with estimates of the equivalent doses using quality factors.

  19. Piezo and pyroelectric radiation dosimetry

    Microsoft Academic Search

    S. Mascarenhas; A. A. d. Carvalho

    1991-01-01

    The use of photoacoustic, piezoelectric, and pyroelectric radiation dosimeters is presented. New results with photoacoustic, pulsed photoacoustic, piezoelectric, and pyroelectric systems are discussed. The characteristics of the new dosimeters developed are compared. A theoretical model to explain the results obtained with the pulsed pyroelectric radiation dosimeter is presented and compared with experimental results. The use of such dosimeters as calorimeters

  20. RADIOFREQUENCY RADIATION: ACTIVITIES AND ISSUES

    EPA Science Inventory

    The question of human safety relative to exposure to RF radiation obviously predates the first ANSI guideline established in 1966, but no enforceable Federal standards or guidelines exist for RF radiation exposure; the ANSI guideline which was revised in 1982 is voluntary or advi...

  1. 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...

  2. Effects Of Radiation On Insulators

    NASA Technical Reports Server (NTRS)

    Bouquet, Frank L.

    1988-01-01

    Report presents data on responses of electrically insulating thermosetting and thermoplastic polymers to radiation. Lowest-threshold-dose (LTD) levels and 25-percent-change levels presented for such properties as tensile strength and electrical resistivity. Data on radiation-induced outgassing also given.

  3. The program RADLST (Radiation Listing)

    SciTech Connect

    Burrows, T.W.

    1988-02-29

    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.

  4. Cardiovascular complications of radiation exposure.

    PubMed

    Finch, William; Shamsa, Kamran; Lee, Michael S

    2014-01-01

    The cardiovascular sequelae of radiation exposure are an important cause of morbidity and mortality following radiation therapy for cancer, as well as after exposure to radiation after atomic bombs or nuclear accidents. In the United States, most of the data on radiation-induced heart disease (RIHD) come from patients treated with radiation therapy for Hodgkin disease and breast cancer. Additionally, people exposed to radiation from the atomic bombs in Hiroshima and Nagasaki, Japan, and the Chernobyl, Ukraine, nuclear accident have an increased risk of cardiovascular disease. The total dose of radiation, as well as the fractionation of the dose, plays an important role in the development of RIHD. All parts of the heart are affected, including the pericardium, vasculature, myocardium, valves, and conduction system. The mechanism of injury is complex, but one major mechanism is injury to endothelium in both the microvasculature and coronary arteries. This likely also contributes to damage and fibrosis within the myocardium. Additionally, various inflammatory and profibrotic cytokines contribute to injury. Diagnosis and treatment are not significantly different from those for conventional cardiovascular disease; however, screening for heart disease and lifelong cardiology follow-up is essential in patients with past radiation exposure. PMID:25290729

  5. Review Article RADIATION SHIELDING TECHNOLOGY

    E-print Network

    Shultis, J. Kenneth

    Review Article RADIATION SHIELDING TECHNOLOGY J. Kenneth Shultis and Richard E. Faw* Abstract Physics Society INTRODUCTION THIS IS a review of the technology of shielding against the effects to the review. The first treats the evolution of radiation-shielding technology from the beginning of the 20th

  6. Cancer risks after radiation exposures

    SciTech Connect

    Voelz, G.L.

    1980-01-01

    A general overview of the effects of ionizing radiation on cancer induction is presented. The relationship between the degree of risk and absorbed dose is examined. Mortality from radiation-induced cancer in the US is estimated and percentages attributable to various sources are given. (ACR)

  7. DCTD — Radiation Research Program (RRP)

    Cancer.gov

    Based in large measure on the CDRP grantees and their mentors, the Radiation Therapy Oncology Group (RTOG) now has a robust Cancer Disparities Committee, and the American Society for Therapeutic Radiology and Oncology (ASTRO) has incorporated a symposium on health disparities into its annual meeting so that addressing health disparities is a strong focus of radiation oncology.

  8. 46: Principles of Radiative Transfer

    Microsoft Academic Search

    MATTHIAS DRUSCH; SUSANNE CREWELL

    The article gives an introduction to classical vector radiative transfer theory (RTT). It comprises a brief summary of the fundamental quantities in RTT and the corresponding definitions. Based on these quantities, the transfer equation for radiation will be introduced in its basic form for a plane-parallel, horizontally homogeneous atmosphere. Polarization and the Stokes vector are introduced, which extend the scalar

  9. Freezing by radiation and convection

    NSDL National Science Digital Library

    Powell, Adam C., IV

    2003-11-20

    Use radiation and a heat transfer coefficient to estimate the initial rate of solidification of the solid shell at the top of a casting while the temperature in the shell can be considered uniform, then set up the equation for mixed conduction/convection-radiation limited cooling.

  10. An introduction to solar radiation

    Microsoft Academic Search

    M. Iqbal

    1983-01-01

    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

  11. Surgical Reconstruction of Radiation Injuries

    PubMed Central

    Fujioka, Masaki

    2014-01-01

    Significance: Patients with cancer receive benefits from radiation therapy; however, it may have adverse effects on normal tissue such as causing radiation-induced ulcer and osteoradionecrosis. The most reliable method to treat a radiation ulcer is wide excision of the affected tissue, followed by coverage with well-vascularized tissue. As usual, radiation-induced skin ulcers are due to therapeutic irradiation for residual cancer or lymph nodes; the locations of radiation ulcers are relatively limited, including the head, neck, chest wall, lumbar, groin, and sacral areas. Thus, suitable reconstructive methods vary according to functional and aesthetic conditions. I reviewed the practices and surgical results for radiation ulcers over the past 30 years, and present the recommended surgical methods for these hard-to-heal ulcers. Recent Advances: At a minimum, flaps are required to treat radiation ulcers. Surgeons can recommend earlier debridement, followed by immediate coverage with axial-pattern musculocutaneous and fasciocutaneous flaps. Free flaps are also a useful soft tissue coverage option. The choice of flap varies with the location and size of the wounds. Critical Issues: The most crucial procedure is the complete resection of the radiation-affected area, followed by coverage with well-vascularized tissue. Future Directions: Recent developments in perforator flap techniques, which are defined as flaps with a blood supply from isolated perforating vessels of a stem artery, have allowed the surgeons to successfully resurface these difficult wounds with reduced morbidity. PMID:24761342

  12. Hawking radiation and Quasinormal modes

    E-print Network

    SangChul Yoon

    2005-10-05

    The spectrum of Hawking radiation by quantum fields in the curved spacetime is continuous, so the explanation of Hawking radiation using quasinormal modes can be suspected to be impossible. We find that quasinormal modes do not explain the relation between the state observed in a region far away from a black hole and the short distance behavior of the state on the horizon.

  13. An introduction to radiation chemistry

    Microsoft Academic Search

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

    1990-01-01

    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.

  14. Radiation damping, noncommutativity and duality

    E-print Network

    E. M. C. Abreu; A. C. R. Mendes; C. Neves; W. Oliveira

    2008-10-15

    In this work, our main objective is to construct a N=2 supersymmetric extension of the nonrelativistic $(2+1)$-dimensional model describing the radiation damping on the noncommutative plane with scalar (electric) and vector (magnetic) interactions by the N=2 superfield technique. We also introduce a dual equivalent action to the radiation damping one using the Noether procedure.

  15. The radiation chemistry of fluoropolymers

    Microsoft Academic Search

    J. S Forsythe; D. J. T Hill

    2000-01-01

    This review covers some of the pioneering work of the radiolysis of fluoropolymers, which started in the mid 1950s and has continued up to the present day. In recent years, there has been renewed interest in the radiolysis of fluoropolymers—extending from the standpoint of radiation degradation in, for example, space environments and nuclear facilities, to the deliberate use of radiation

  16. Quantitative assessment of radiation hormesis

    SciTech Connect

    Rogers, V.C.; Wilde, T.S. [Rogers & Associates, Salt Lake City, UT (United States); Sandquist, G.M. [Univ. of Utah, Salt Lake City, UT (United States)

    1997-12-01

    A mathematical model for radiation hormesis has been developed and is graphically and quantitatively evaluated here. The model incorporates both cancer induction based on the linear dose model and cancer suppression by hormesis. The hormesis model is assessed for its ability to predict observed cancer incidence for arbitrary radiation release distribution.

  17. The cosmic microwave background radiation

    Microsoft Academic Search

    R. W. Wilson

    1979-01-01

    The discovery of the cosmic microwave background radiation is discussed beginning with radio astronomical measuring techniques, followed by the history of the detection of background radiation, and a summary of some of its properties. Attention is given to the design and operation of a radiotelescope, its antenna and radiometer, exhibiting its advantages, including the ability to measure a collecting area

  18. The cosmic microwave background radiation

    Microsoft Academic Search

    Joseph Silk

    1981-01-01

    Because angular anisotropies and spectral distortions of the cosmic microwave background radiation are judged to be inevitable at some level, in a realistic cosmological model, the evidence for spectral distortions and its theoretical implications are described. The evidence for anisotropy is then discussed, and theoretical predictions of radiation anisotropy are summarized and compared with the data available. It is found

  19. Applications of the Radiation Pressure

    E-print Network

    Palffy-Muhoray, Peter

    Applications of the Radiation Pressure Prepared: Volodymyr Borshch Course: LC Optics and Photonics in 1871 · The predicted value of the light pressure 4.7 x 10-6 Pa · And also Adolfo Bartoli in 1876 #12 and 10-6 torr (maximum effect 10-2 torr) · DOES NOT demonstrate radiation pressure #12;8 Nichols

  20. Teaching about Natural Background Radiation

    ERIC Educational Resources Information Center

    Al-Azmi, Darwish; Karunakara, N.; Mustapha, Amidu O.

    2013-01-01

    Ambient gamma dose rates in air were measured at different locations (indoors and outdoors) to demonstrate the ubiquitous nature of natural background radiation in the environment and to show that levels vary from one location to another, depending on the underlying geology. The effect of a lead shield on a gamma radiation field was also…