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Sample records for biologischen dosimetrie bei

  1. Dosimetry for SIRT; Dosimetrie bei der SIRT

    Energy Technology Data Exchange (ETDEWEB)

    Mueller, S.P. [Universitatesklinikum Essen (Germany). Klinik fuer Nuklearmedizin

    2011-09-15

    Dosimetry is only one aspect of treatment planning for 'Selective internal radiotherapy' (SIRT) or 'transarterial radioembolization' (TARE) with Yttrium-90 Microspheres is an emerging palliative therapy for malignant hepatoma. Dosimetric considerations, together with interventional, oncological and hepatological aspects need to be considered for optimal treatment stratification. The product-specific dosimetric calculations for 2 commercially available microsphere products are compared and set in relation to the average doses to liver and tumor. Ostensible discrepancies between the dose-response of Y-90-microspheres and external beam radiation therapy are discussed in the context of radiobiological concepts. (orig.)

  2. Nutrient removal at the waste water treatment plant at Wathlingen. Special aspects of the enhanced biological phosphorus removal; Naehrstoffelemination auf der Klaeranlage Wathlingen. Besonderheiten bei der erhoehten biologischen Phosphatelimination

    Energy Technology Data Exchange (ETDEWEB)

    Meyer, D. [Fachhochschule Suderburg (Germany); Fladerer, F. [Fachhochschule Suderburg (Germany)

    1996-01-01

    The article describes the problem of the nutrient removal in communal wastewater treatment plants. As an example the investigations about the optimisation of the denitrification and the enhanced biological phosphorus removal on the Wathlingen Wastewater Treatment Plant are explained. In this case the most important subjects are the anaerobic P-release despite a high amount of nitrate in the return sludge entering the anerobic tank, followed by an anoxic P-uptake in the denitrification zone before entering the aerobic tank for nitrification. Furthermore there is a short description of improvement measures carried out. The obtained effluent values show the success of these improvements. The specific P-dynamic in the treatment system requires conclusions supporting the optimisation of the nutrient removal in treatment plants using enhanced biological P-elimination and denitrification before nitrification. (orig.) [Deutsch] Der Artikel befasst sich mit der Problematik der Naehrstoffelimination auf kommunalen Klaeranlagen. Am Beispiel der Untersuchungen zur Optimierung der Dentrifikation und erhoehten biologischen Phosphorelimination auf der Klaeranlage Wathlingen werden Besonderheiten der biologischen P-Elimination dargestellt. Dabei geht es vor allem um eine anaerobe P-Freisetzung bei intermittierender Schlammumwaelzung im anaeroben Becken und gleichzeitigen hohen Nitrateintraegen ueber den Ruecklaufschlamm. Ebenso erfolgt die Darstellung der sich anschliessenden anoxischen P-Aufnahme im vorgeschalteten Denitrifikationsbecken. Des weiteren werden die druchgefuehrten Optimierungen kurz beschrieben und die damit erzielten Ablaufwerte aufgefuehrt. Schlussfolgerungen fuer die Prozessfuehrung bei Anlagenkonfigurationen mit biologischer P-Elimination und vorgeschalteter Denitrifikation ergeben sich aus dem Phaenomen der anoxischen Phosphataufnahme. (orig.)

  3. The relevance of biological dosimetry in controversial judgements about low level effects in populations; Die Aussagekraft der biologischen Dosimetrie bei Kontroversen ueber Strahlenfolgen im Niederdosisbereich

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz-Feuerhake, Inge

    2009-07-01

    Radiation-specific structural chromosome aberrations include dicentric chromosomes which are most sensitive to prove exposures in individuals and cohorts of persons. The reasons are their very low spontaneous rate and their instability which leads to a kind of equilibrium because no relevant accumulation occurs during lifetime by natural or civil exposures. The doubling dose in case of an acute homogenous whole body exposure is about 10 mSv. For example, a review about findings in populations exposed by Chernobyl fallout is presented which shows, that the dose estimates of UNSCEAR and WHO are not reliable. While these result even for highly contaminated regions in values in the range of a few mSv, the aberration rates in many and numerous samples of the population showed a multifold elevation compared to normal background rates. An underestimation of the true exposure by the physical calculation in the range of 1-2 orders of magnitude must be considered. Similar conclusions can be drawn for the accident of Three Mile Island in 1979, the effects near nuclear establishments in regular conditions and for air craft personnel. (orig.)

  4. Dosimetry in radioiodine therapy of benign thyroid diseases. Background and practice; Dosimetrie bei Radioiodtherapie benigner Schilddruesenerkrankungen. Hintergrund und Durchfuehrung

    Energy Technology Data Exchange (ETDEWEB)

    Bockisch, A.; Sonnenschein, W.; Jentzen, W.; Hartung, V.; Goerges, R. [Universitaetsklinikum Essen (Germany). Klinik fuer Nuklearmedizin

    2008-09-15

    Radioiodine therapy of benign thyroid diseases (focal = [toxic adenoma], multifocal, disseminated autonomy, Grave's disease or clinical relevant goitre) needs to be and can be performed individually for each patient. Most frequently a radioiodine test is performed applying a small activity of iodine-131 ({sup 131}I). The paper discusses some protocols for pre- or posttherapeutic dosimetry and discusses their advantages and disadvantages. All are based on the volumetry of the target tissue as well as the radioiodine kinetics in the target volume what may be represented by maximum uptake and half life of iodine retention in the thyroid. Possible disturbances and measuring uncertainties of these parameters are presented and discussed. In spite of the discussed uncertainties in dosimetry, due to its high therapeutic width radioiodine therapy is a very successful procedure to cure hyperthyroidism or to reduce goitre volume with only little side effects. (orig.)

  5. Practical experiences with the acidification of primary sludges and the influence on the economy of the advanced biological phosphorus removal; Praktische Erfahrungen mit der Schlammversaeuerung und deren Einfluss auf die Wirtschaftlichkeit bei der vermehrten biologischen Phosphoreliminierung

    Energy Technology Data Exchange (ETDEWEB)

    Pokorny, U. [Zivilingenieurbuerot, Innsbruck (Austria); Buchauer, K.

    1999-07-01

    At 2 wastewater treatment plants in Tyrolia, Austria, large-scale experiences with the acidification of primary sludge were made. The operational results are presented and analysed critically with special focus on nutrient removal. The economical calculations derived thereof show that in case of a newly constructed wastewater treatment plant total costs including investment and operation can be reduced by approximately 5%. In case of an existing plant which is adapted to new demands the financial benefits can be even higher, because of the frequent possibility to use existing units for acidification. (orig.) [German] Auf 2 Klaeranlagen in Tirol, Oesterreich, wurden grosstechnische Erfahrungen mit dem gezielten Einsatz von versaeuertem Primaerschlamm gesammelt. Die Betriebsergebnisse werden vorgestellt und kritisch analysiert, wobei insbesondere auf die Auswirkungen bezueglich Naehrstoffelimination naeher eingegangen wird. Die daraus abgeleiteten Wirtschaftlichkeitsberechnungen zeigen, dass sich bei einem Klaeranlagen-Neubau die Gesamtkosten aus Investitionen und Betrieb auf einfache Weise um ca. 5% vermindern lassen. Bei Umbauten von Klaeranlagen ist die Wirtschaftlichkeit oft noch wesentlich hoeher, da haeufig bestehende Anlagenteile zur Versaeuerung genutzt werden koennen.

  6. Intensifying enhanced biological phosphorus removal by calciumdolomitehydrate; Intensivierung der vermehrten biologischen Phosphatelimination durch Dolomitkalkhydrat

    Energy Technology Data Exchange (ETDEWEB)

    Soelter, M. [AKDOLIT GmbH, Wuelfrath (Germany)

    1999-02-01

    Utilization of enhanced biological phosphorus removal is increasingly considered an essential part in designing wastewater treatment plant due to ecological and economical advantages. Effects of Akdophos (=special dolime-hydrate) were investigated and monitored in operational tests at the industrial effluent clarification plant of Gerolsteiner Brunnen and the municipal plant Dremmen. Results of a full year cyclus demonstrate the efficiency of Akdophos in stabilizing and intensifying the enhanced Bio-P removal. Cost-analysis shows a considerable cost cutting potential regarding precipitants as well as improvement of sludge volume index with only low increase of excess sludge. Dry product dosage of Akdophos to the aeration tank has been proved a reliable and cost-effective process method. (orig.) [Deutsch] Oekokogische und oekonomische Vorteile bestaetigen zunehmend die Nutzung der erweiterten biologischen Phosphatelimination als wesentlichen Bestandteil der Konzeption von Abwasserreinigungsanlagen. Anhand grosstechnischer Versuche auf der Klaeranlage des Gerolsteiner Brunnen und auf der Klaeranlage Dremmen (Stadt Heinsberg) wurde die Wirkung von Akdorphos (=speziell hergestelltes Dolomitkalkhydrat) auf die biologischen Vorgaenge von Klaeranlagen untersucht. Im Betrieb ueber einen vollstaendigen Jahreszyklus konnte nachgewiesen werden, dass die biologische Phosphatelimination durch eine geringfuegige Dosierung von Akdophos intensiviert und stabilisiert wird. Die Kostenanalyse in beiden betrachteten Faellen zeigt neben einer Kostenreduktion bei den Faellmitteln weitere Einsparungen durch deutlich verbesserte Schlammabsetzeigenschaften bei sehr geringem Schlammehranfall. Die Dosierung von Akdophos erfolgt vorzugsweise trocken und unmittelbar in die Belebung. Die entsprechende Anlagentechnik hat sich als betriebssicher und kostenguenstig erwiesen. (orig.)

  7. DOSIMETRY

    CERN Multimedia

    Service de dosimétrie individuelle

    2000-01-01

    From the distribution Novembre/Decembre 2000 (film colour green), the people who worked in LEP experiments and who have not announced their participation to LEP dismantling or new activities in another experiment or group will be taken out from the regular distribution list of the Individual Dosimetry Service. Please contact Individual Dosimetry Service, tel. 72155 or e-mail to Jeannine.Fraisse@cern.ch We inform all staff and users under regular dosimetric control that the dosimeters for the monitoring period SEPTEMBER/OCTOBER will be available from their usual dispatchers on the 1st of September 2000. Please have your films changed before the 12th of September. The colour of the dosimeter valid in SEPTEMBER/OCTOBER is RED. The service will be closed exceptionally on Friday 8 September.

  8. DOSIMETRY

    CERN Multimedia

    2001-01-01

    From the month of May on, the neutron dosimeter will be worn in an extra package distinct from the usual film-badge. We will give you more ample information in Weekly Bulletin No. 18/2001 of April 30, 2001. In the week following Easter (17 - 20. 4. 2001) the Individual Dosimetry Service will be opened in the mornings from 8:30 to 11:30 h only. The Service will be closed on April 30.

  9. Low-dose testicular irradiation in seminoma patients. In-vivo dosimetry; Gonadenbelastung bei Lymphabflussbestrahlung operierter Seminome. In-vivo-Dosimetrie

    Energy Technology Data Exchange (ETDEWEB)

    Gruber, G.; Schwegler, N. [Kantonsspital Aarau (Switzerland). Abt. Strahlentherapie

    1999-04-01

    measurements. (orig.) [Deutsch] Hintergrund: Dieser Beitrag soll die Problematik bezueglich Gonadenbelastung bei der Lymphabflussbestrahlung operierter Seminome, eigene Ergebnisse von Schutzmassnahmen sowie moegliche Konsequenzen fuer Therapie und Patientenberatung aufzeigen. Patienten und Methode: Seit November 1993 wurde im Rahmen der `Hockey-stick`-Bestrahlung bei 43 Patienten im Stadium I/II nach Royal Marsden die Gonadendosis mit Hilfe zweier Ionisationskammern in insgesamt 80 Messungen bestimmt, bei sechs Patienten im Direktvergleich mit und ohne Schutz. Die Bestrahlung erfolgte anterior-posterior/posterior-anterior (ap/pa) an einem 6-MV-Linearbeschleuniger bis zu einer Gesamtdosis von 34,2 (n=13), spaeter 30,6 Gy (n=30). Eine Abschirmung, anfaenglich selbst kreiert (n=6), spaeter in Form einer industriell gefertigten Hodenkapsel von ap, wurde 33mal verwendet. Zehn Patienten mit abgeschlossenem Kinderwunsch erhielten keinen Gonadenschutz. Bei sechs konnte ein Direktvergleich mit und ohne Schutz vorgenommen werden. Mit der Anfertigung eines Spermiogramms kurz vor Radiotherapiebeginn erklaerten sich 25 Patienten einverstanden. Ergebnisse: Bei 56% der untersuchten Patienten liess sich eine Oligo- oder Azoospermie vor Radiotherapiebeginn feststellen. Die mittlere Gonadendosis betrug bei Patienten ohne Hodenschutz (n-Patienten=10, m-Messungen=15) rund 2,4% der Referenzdosis (RD) (4,8 cGy), bei Patienten mit dem Eigenbau (n=6, m=7) 1,8% RD (3,2 cGy) und zusaetzlich angelegter Hodenkapsel (n=33, m=58) lediglich 1,0% RD (1,8 cGy) pro Fraktion. Die korrespondierenden Medianwerte betrugen 2,1% (SD 1,07), 1,7% (SD 0,28) und 1,0% (SD 0,41) RD. Aufgrund des Direktvergleichs bei sechs Patienten laesst sich im Normalfall eine Reduktion auf rund die Haelfte erwarten. Individuelle Dosisschwankungen von 11,6% im Mittel (median 10%) muessen dabei beruecksichtigt werden. Schlussfolgerung: Schutzmassnahmen stellen neben einer Abstandserhoehung eine ausgezeichnete Moeglichkeit dar, die

  10. Knochenstoffwechsel bei malignen Erkrankungen

    Directory of Open Access Journals (Sweden)

    Keck A-V

    2003-01-01

    Full Text Available Bei malignen Erkrankungen, wie dem Mammakarzinom, dem Prostatakarzinom, dem Bronchialkarzinom oder dem multiplen Myelom ist der Knochen eines der am häufigsten von Metastasen betroffenen Organe. Das klinische Beschwerdebild ist durch das Auftreten pathologischer Frakturen, Schmerzen und Hyperkalzämien gekennzeichnet. Eine erhöhte Knochenresorptionsrate und Verlust an Knochenmasse im Sinne von osteoporoseartigen Veränderungen bedingt durch eine inadäquat überschießende Osteoklastendifferenzierung und -aktivierung sind ursächlich dafür verantwortlich. Durch jüngst publizierte Ergebnisse diverser Studien und Untersuchungen konnten die genauen Mechanismen der Rekrutierung und Aktivierung von Osteoklasten weiter aufgeklärt werden. Receptor activator of nuclear factor-kappa-B ligand (RANKL, ein Mitglied der Tumor necrosis factor (TNF Superfamilie konnte als entscheidender Faktor in der Osteoklastengenese identifiziert werden. Die Interaktion von RANKL mit seinem Rezeptor RANK (receptor activator of nuclear factor-kappa-B induziert die Entwicklung der osteoklastären Reihe aus dem hämatopoetischen Kompartment und fördert weiters die Differenzierung zu Osteoklastenvorstufen und die Aktivierung reifer Osteoklasten, ebenso wird eine verzögert einsetzende Apoptose bewirkt. Neben RANK und RANKL ist Osteoprotegerin (OPG als dritte Komponente in der Regulation der Knochenresorption involviert. Als Mitglied der TNF-Superfamilie bindet OPG an RANKL und blockiert somit alle stimulierenden Effekte von RANK auf die Osteoklastenentwicklung und neutralisiert so alle biologischen Effekte von RANKL. Diverse Hormone und Zytokine üben durch die Modifikation der Ratio von RANKL zu OPG einen regulatorischen Effekt auf die Knochenresorption aus. Diese ist bei osteolytischen Knochenmetastasen, beim multiplen Myelom und bei der malignen Hyperkalzämie erhöht. Das Gleichgewicht knochenaufbauender wie -abbauender Mechanismen scheint somit durch die Ratio von

  11. Endokrinologische Behandlung der Geschlechtsdysphorie bei Menschen mit Geschlechtsinkongruenz

    Directory of Open Access Journals (Sweden)

    Flütsch N

    2015-01-01

    Full Text Available Es gibt Menschen, die die innere Gewissheit besitzen, dass ihre Geschlechtsidentität nicht zu ihrem biologischen Ursprungsgeschlecht passt. Durch die Entwicklungen in der Medizin in den letzten hundert Jahren ist es möglich geworden, die körperlichen Geschlechtsmerkmale an das innerlich erlebte Geschlecht anzupassen. Die Zahl der Hilfesuchenden in den ärztlichen Ambulanzen und Privatpraxen hat in den vergangenen Jahren deutlich zugenommen. Das Vorgehen bei der Diagnostik und Therapieeinleitung erlebt zurzeit eine deutliche Veränderung hin zu mehr Patientenzentriertheit und Individualisierung des Transitionsprozesses. Dabei bildet die geschlechtsangleichende Hormontherapie ein wesentliches Standbein in der körperlichen Angleichung an das Gegengeschlecht. Unter Beachtung von bestimmten Sicherheitsaspekten ist eine Hormontherapie mit Sexualhormonen sicher und einfach durchzuführen. Regelmäßige Verlaufskontrollen sowie der offene und affirmative Umgang mit den Betroffenen tragen zudem wesentlich zur Sicherheit in der Behandlung bei.

  12. Influence of enhanced biological phosphate removal on feedback of phosphorus from sludge treatment; Einfluss der erhoehten biologischen Phosphorelimination auf die Phosphorrueckbelastung aus der Schlammbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Jardin, N. [Inst. WAR, TH Darmstadt (Germany); Poepel, H.J. [Inst. WAR, TH Darmstadt (Germany)

    1995-06-01

    Phosphate release and phosphate fixation during sludge treatment of excess sludge was investigated with a pilot plant for enhanced biological phosphorus removal. The major part of the eliminated phosphorus in the pilot plant was due to the storage of polyphosphate in the excess sludge and was accompanied by an uptake of magnesium and potassium. Using separate thickening systems only a small P-feedback was observed, whereas with gravity thickeners a part of the polyphosphate was hydrolysed and phosphate was released into solution. Due to only a small transfer of the released phosphate from the sludge layer into the supernatant, the P-feedback was relatively low. As a result of a complete polyphosphate hydrolysis in stabilising systems, phosphate is released, but only a small part of the released phosphate remains in solution whereas the major fraction of the released phosphate was fixed by physico-chemical fixation mechanisms. (orig.) [Deutsch] Es wird ueber systematische Untersuchungen im halbtechnischen Massstab zum Einfluss der erhoehten biologischen Phosphorelimination auf die Phosphatrueckloesung und Phosphatrueckbelastung bei der Schlammbehandlung berichtet. Die durchgefuehrten Untersuchungen zeigten, dass der groesste Teil des im erhoehten Umfang gespeicherten Phosphors auf die Einlagerung von Polyphosphat zurueckzufuehren ist, wobei gleichzeitig auch Kalium- und Magnesiumionen aufgenommen werden. Die maschinellen Verfahren zur getrennten Ueberschussschlammeindickung verursachen nur eine geringe P-Rueckbelastung, waehrend bei der Schwerkrafteindickung das Polyphosphat teilweise hydrolysiert und als Phosphat rueckgeloest wird. Allerdings wurde nur ein geringer Transfer in den Ueberstand beobachtet, so dass die P-Rueckbelastung auch bei der Schwerkrafteindickung vergleichsweise gering war. Bei der Faulung und der aerob-thermophilen Stabilisierung wird das Polyphosphat vollstaendig hydrolisiert, aber nur ein kleiner Teil des freigesetzten Phosphats verbleibt in

  13. Airborne microbial emissions and immissions on aerogic mechanical-biological waste treatment plants; Luftgetragene mikrobielle Emissionen und Immissionen an aeroben mechanisch-biologischen Abfallbehandlungsanlagen

    Energy Technology Data Exchange (ETDEWEB)

    Luft, C.

    2002-07-01

    kommt. Darum ist es wichtig, die von biologischen Abfallbehandlungsanlagen ausgehenden Keimemissionen und Keimimmissionen zu bestimmen. Im Rahmen der vorliegenden Arbeit wurden diesbezuegliche Untersuchungen vorgenommen. Es wurden unter kritischer Beurteilung der eingesetzten Messverfahren Keimkonzentrationen verschiedener Mikroorganismen und Endotoxine an unterschiedlichen mechanisch-biologischen Anlagentypen ermittelt. Es wurden sowohl geschlossene wie auch offene Anlagen untersucht. Darueber hinaus wurden neben Bioabfallkompositierungsanlagen auch eine Restabfallbehandlungsanlage getestet. Es zeigt sich, dass anlagenabhaengig sehr unterschiedliche Keimkonzentrationen auftraten. In Abhaengigkeit von Anlagengroesse, verarbeitetem Material und dem Grad der Einhausung traten unterschiedliche Konzentrationen auf. So waren bei einer kleinen offenen Anlage (6 500 Mg/a) die geringsten Belastungen in den Arbeitsbereichen festzustellen, waehrend bei der geschlossenen Anlage (12 000 Mg/a) doch erhebliche Keimkonzentrationen an den Arbeitsplaetzen festzustellen waren. Jahreszeitliche Schwankungen bei einer offenen Anlage konnten fuer Keimzahlbestimmungen nicht festgestellt werden, Endotoxinmessungen zeigten hingegen eine jahreszeitliche Abhaengigkeit. Immissionsseitig wurde anhand von Simulationsversuchen mit den Modellen nach TA-Luft sowie nach VDI 3783 prognostiziert, dass bei einer mittelgrossen (12 000 Mg/a), eingehausten Anlage mit Biofilter Keimkonzentrationen auftreten, die nur geringen Einfluss auf die Umgebung nehmen. (orig.)

  14. Dosimetry; La dosimetrie

    Energy Technology Data Exchange (ETDEWEB)

    Le Couteulx, I.; Apretna, D.; Beaugerie, M.F. [Electricite de France (EDF), 75 - Paris (France)] [and others

    2003-07-01

    Eight articles treat the dosimetry. Two articles evaluate the radiation doses in specific cases, dosimetry of patients in radiodiagnosis, three articles are devoted to detectors (neutrons and x and gamma radiations) and a computer code to build up the dosimetry of an accident due to an external exposure. (N.C.)

  15. Radiation dosimetry

    CERN Document Server

    Hine, Gerald J; Hine, Gerald J

    1956-01-01

    Radiation Dosimetry focuses on the advancements, processes, technologies, techniques, and principles involved in radiation dosimetry, including counters and calibration and standardization techniques. The selection first offers information on radiation units and the theory of ionization dosimetry and interaction of radiation with matter. Topics include quantities derivable from roentgens, determination of dose in roentgens, ionization dosimetry of high-energy photons and corpuscular radiations, and heavy charged particles. The text then examines the biological and medical effects of radiation,

  16. Hematological dosimetry. Dosimetrie hematologique

    Energy Technology Data Exchange (ETDEWEB)

    Fluery-Herard, A. (CEA Centre d' Etudes de Fontenay-aux-Roses, 92 (FR). Direction des Sciences du Vivant)

    1991-01-01

    The principles of hematological dosimetry after acute or protracted whole-body irradiation are reviewed. In both cases, over-exposure is never homogeneous and the clinical consequences, viz medullary aplasia, are directly associated with the mean absorbed dose and the seriousness and location of the overexposure. The main hematological data required to assess the seriousness of exposure are the following: repeated blood analysis, blood precursor cultures, as indicators of whole-body exposure; bone marrow puncture, medullary precursor cultures and medullary scintigraphy as indicators of the importance of a local over-exposure and capacity for spontaneous repair. These paraclinical investigations, which are essential for diagnosis and dosimetry, are also used for surveillance and for the main therapeutic issues.

  17. Dosimetry Service

    CERN Multimedia

    2006-01-01

    Cern Staff and Users can now consult their dose records for an individual or an organizational unit with HRT. Please see more information on our web page: http://cern.ch/rp-dosimetry Dosimetry Service is open every morning from 8.30 - 12.00. Closed in the afternoons. We would like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCT's) must always be returned to the Service after the use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel. 7 2155 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  18. {sup 177}Lutetium-DOTATATE peptide radio-receptor therapy for patients with endocrine neoplasm and the individualized semi-automatic dosimetry. A retrospective analysis; {sup 177}Lutetium-DOTATATE-Peptid-Radio-Rezeptor-Therapie bei Patienten mit neuroendokrinen Neoplasien und die individualisierte, semi-automatische-Dosimetrie. Eine retrospektive Analyse

    Energy Technology Data Exchange (ETDEWEB)

    Loeser, Anastassia

    2016-09-28

    The {sup 177}lutetium-DOTATATE peptide radio-receptor therapy is a promising approach for the palliative treatment of patients with inoperable endocrine neoplasm. The individually variable biological dispersion and the tumor uptake including the protection of critical organs require a precise and reliable organ and tumor dosimetry. The HERMES Hybrid dosimetry module has appeared as reliable and user-friendly tool for clinical application. The next step is supposed to by the complete integration of 3D SPECT imaging.

  19. Die Psychosen bei Epilepsie

    Directory of Open Access Journals (Sweden)

    Glauninger G

    2001-01-01

    Full Text Available In einer Übersicht werden die verschiedenen Formen psychotischer Zustandsbilder bei Epilepsiepatienten, deren Ätiopathogenese und Möglichkeiten der Behandlung dieser Störungen beschrieben. Risikofaktoren finden sich durch neurobiologische Gegebenheiten - besonders bei Mitbeteiligung des Temporallappens, durch psychosoziale Einflüsse und manchmal auch durch medikamentöse Behandlung. Anhand von Fallbeispielen sollen dem Leser typische Krankheitsverläufe von psychotischen Episoden bei Epilepsiepatienten, die zumeist erst bei einer schon länger dauernden Epilepsie auftreten, nähergebracht werden. Es wird deutlich, daß sich die Beschwerden von Patienten mit Epilepsie nicht auf iktale Phänomene beschränken. Bei der Behandlung dieser Patienten kommt einer guten interdisziplinären Zusammenarbeit besondere Bedeutung zu.

  20. Strahlungsmessung und Dosimetrie

    CERN Document Server

    Krieger, Hanno

    2013-01-01

    „Strahlungsquellen und Dosimetrie“ ist Teil einer Lehrbuchreihe zur Strahlungsphysik und zum Strahlenschutz. Der erste Teil befasst sich mit den physikalischen Grundlagen der Strahlungsdetektoren und der Strahlungsmessung. Im zweiten Teil werden die Konzepte und Verfahren der klinischen Dosimetrie dargestellt. Der dritte Abschnitt erläutert ausführlich die Dosisverteilungen der klinisch angewendeten Strahlungsarten. Im vierten Teil werden weitere Messaufgaben der Strahlungsphysik einschließlich der Messsysteme für die Bildgebung mit Röntgenstrahlung dargestellt. Neben den grundlegenden Ausführungen enthält dieser Band im laufenden Text zahlreiche Tabellen und Grafiken zur technischen und medizinischen Radiologie, die bei der praktischen Arbeit sehr hilfreich sein können und 199 Übungsaufgaben mit Lösungen zur Vertiefung der Inhalte. Für die zweite Auflage wurden die Darstellungen der Elektronen- und der Protonendosimetrie sowie der bildgebenden Verfahren mit Computertomografen deutlich erweit...

  1. Computational dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Siebert, B.R.L.; Thomas, R.H.

    1996-01-01

    The paper presents a definition of the term ``Computational Dosimetry`` that is interpreted as the sub-discipline of computational physics which is devoted to radiation metrology. It is shown that computational dosimetry is more than a mere collection of computational methods. Computational simulations directed at basic understanding and modelling are important tools provided by computational dosimetry, while another very important application is the support that it can give to the design, optimization and analysis of experiments. However, the primary task of computational dosimetry is to reduce the variance in the determination of absorbed dose (and its related quantities), for example in the disciplines of radiological protection and radiation therapy. In this paper emphasis is given to the discussion of potential pitfalls in the applications of computational dosimetry and recommendations are given for their avoidance. The need for comparison of calculated and experimental data whenever possible is strongly stressed.

  2. BEI Resource Repository

    Data.gov (United States)

    U.S. Department of Health & Human Services — BEI Resources provides reagents, tools and information for studying Category A, B, and C priority pathogens, emerging infectious disease agents, non-pathogenic...

  3. Neues bei Kopfschmerzen

    Directory of Open Access Journals (Sweden)

    Diener HC

    2010-01-01

    Full Text Available Neue epidemiologische Studien waren in der Lage, Faktoren zu identifizieren, die den Übergang von episodischer zur chronischen Migräne voraussagen. Zu diesen gehören die häufige Einnahme von Migräne- oder Schmerzmitteln, psychiatrische Begleitmorbidität und niedrige soziale Schicht. In der Migräneprophylaxe zeigte sich Botulinumtoxin bei chronischer Migräne wirksam. Valproinsäure ist bei der Migräne bei Jugendlichen zur Prophylaxe nicht wirksam. Eine neue Option zur Behandlung des chronischen therapieresistenten Clusterkopfschmerzes ist die bilaterale chronische Stimulation des Nervus occipitalis major. Beim Pseudotumor cerebri muss nicht zwangsläufig eine Stauungspapille nachweisbar sein. Bei klinischem Verdacht muss daher zum sicheren Ausschluss eine Liquorpunktion mit Druckmessung erfolgen.

  4. Stammzelltherapie bei PAVK

    Directory of Open Access Journals (Sweden)

    Kopp CW

    2005-01-01

    Full Text Available Die autologe Stammzelltransplantation zur Induktion therapeutischer Angiogenese stellt eine potentiell beinerhaltende Therapieoption bei chronisch kritischer Extremitätenischämie bei Patienten ohne chirurgische oder interventionelle Revaskularisationsmöglichkeit dar. Die folgende Übersicht soll das zugrundeliegende Konzept dieses Therapieansatzes und klinische Richtlinien für die Ausschöpfung des angiogenetischen Potentials von Knochenmarksstammzellen vorstellen. Im Ausblick werden die "Stammzell-Mobilisation" und das gezielte "Homing" als Alternative zur Stammzelltransplantation umrissen.

  5. Osteoporose bei polyzystischem Ovarsyndrom

    Directory of Open Access Journals (Sweden)

    Lerchbaum E

    2015-01-01

    Full Text Available Das polyzystische Ovarsyndrom (PCOS ist die häufigste Endokrinopathie bei Frauen im gebärfähigen Alter und geht mit Oligo- oder Anovulation, klinischem oder biochemischem Hyperandrogenismus und polyzystischen Ovarien einher. Während die Hyperandrogenämie einen potenziell protektiven Faktor hinsichtlich der Osteoporose darstellt, könnte das im Rahmen der gestörten Ovulation häufig vorhandene Östrogendefizit den Knochenstoffwechsel und das Osteoporoserisiko ungünstig beeinflussen. Weiters treten beim PCOS gehäuft metabolische Probleme wie Adipositas, Insulinresistenz, Glukosestoffwechselstörungen und das metabolische Syndrom auf, die ebenfalls Einfluss auf den Knochen nehmen können. Auch die medikamentöse Therapie des PCOS wie hormonelle Kontrazeptiva, Antiandrogene und Insulinsensitizer können das Osteoporoserisiko modifizieren. Die bisherige Datenlage zur Knochendichte (BMD beim PCOS ist unklar, die Ergebnisse reichen von ähnlichen Werten bei PCOS und gesunden Frauen, über bessere BMD-Werte bei PCOS-Frauen bis hin zu schlechteren BMD-Werten vor allem bei amenorrhoischen Frauen mit PCOS. Die bislang einzige Studie zum Frakturrisiko bei postmenopausalen Frauen mit PCOS ergab keinen Unterschied zwischen PCOS-Frauen und gesunden Kontrollen. Somit kann anhand der derzeitigen Datenlage nicht zufriedenstellend beurteilt werden, ob das PCOS einen möglichen Risikofaktor für die Osteoporose darstellt oder, im Gegenteil, ein eher protektiver Faktor ist. Es besteht ein großer Bedarf an prospektiven Studien mit adäquater Fallzahl auch bei postmenopausalen Frauen mit PCOS, um diese Frage beantworten zu können. Derzeit muss jede Frau mit PCOS, das ein sehr heterogenes Krankheitsbild darstellt, individuell hinsichtlich des möglichen Osteoporoserisikos beurteilt werden. Der Zusammenhang zwischen PCOS und Osteoporose sollte in Zukunft sowohl in der klinischen Routine als auch bei künftigen Studien vermehrt Beachtung finden.

  6. Dosimetry methods

    DEFF Research Database (Denmark)

    McLaughlin, W.L.; Miller, A.; Kovacs, A.;

    2003-01-01

    Chemical and physical radiation dosimetry methods, used for the measurement of absorbed dose mainly during the practical use of ionizing radiation, are discussed with respect to their characteristics and fields of application.......Chemical and physical radiation dosimetry methods, used for the measurement of absorbed dose mainly during the practical use of ionizing radiation, are discussed with respect to their characteristics and fields of application....

  7. Dosimetry Service

    CERN Multimedia

    Dosimetry Service

    2005-01-01

    Please remember to read your dosimeter at least once every month. A regular read-out is indispensable to ensure periodic monitoring of your personal dose. You must read your dosimeter even if you have not visited the controlled areas. Film badges are no longer valid at CERN and holders of film badges are no longer allowed to enter the controlled radiation areas or work with a source. Dosimetry Service Tel. 72155 http://cern.ch/rp-dosimetry

  8. Epid Dosimetry

    Science.gov (United States)

    Greer, Peter B.; Vial, Philip

    2011-05-01

    Electronic portal imaging devices (EPIDs) were introduced originally for patient position verification. The idea of using EPIDs for dosimetry was realised in the 1980s. Little was published on the topic until the mid 1990's, when the interest in EPIDs for dosimetry increased rapidly and continues to grow. The increasing research on EPID dosimetry coincided with the introduction of intensity modulated radiation therapy (IMRT). EPIDs are well suited to IMRT dosimetry because they are high resolution, two-dimensional (2D) digital detectors. They are also pre-existing on almost all modern linear accelerators. They generally show a linear response to increasing dose. Different types of EPIDs have been clinically implemented, and these have been described in several review papers. The current generation of commercially available EPIDs are indirect detection active matrix flat panel imagers, also known as amorphous silicon (a-Si) EPIDs. Disadvantages of a-Si EPIDs for dosimetry include non-water equivalent construction materials, and the energy sensitivity and optical scatter of the phosphor scintillators used to create optical signal from the megavoltage beam. This report discusses current knowledge regarding a-Si EPIDs for dosimetry.

  9. Development of a test system for the determination of biodegradability in surface waters; Entwicklung eines Testsystems fuer die Pruefung des biologischen Abbaus in Oberflaechengewaessern

    Energy Technology Data Exchange (ETDEWEB)

    Kalsch, W.; Knacker, T.; Robertz, M.; Schallnass, H.J.

    1997-04-01

    kontrollierten Bedingungen bis zu 92 Tage lang inkubiert. Die Ergebnisse zeigten, dass die Wasser/Sediment-Systeme auch ueber diesen langen Zeitraum ohne Zufuetterung biologisch stabil waren und nichtreduzierende Bedingungen auch im Sediment erhalten blieben. Die Mineralisierung von 4-Nitrophenol wurde vom Sedimenttyp, der Belueftungsart und der Temperatur beeinflusst, die von Lindan von der Applikationsart und ebenfalls vom Sedimenttyp und der Temperatur. Wesentliche Anteile der Radioaktivitaet wurden ans Sediment gebunden und waren zum grossen Teil nicht extrahierbar. Es wird schliesslich diskutiert, dass das Potential eines Sediments, Stoffe zu minimalisieren, nicht mit den gewaehlten biologischen Kenngroessen klassifiziert werden kann. Daraus koennen Probleme bei der Uebertragbarkeit der Ergebnisse auf neue Standorte erwachsen. (orig.)

  10. Herzbeteiligung bei Myopathien

    Directory of Open Access Journals (Sweden)

    Finsterer J

    2001-01-01

    Full Text Available Herzbeteiligung bei Patienten mit Myopathien wird zunehmend häufiger diagnostiziert. Sie manifestiert sich bei diesen Patienten als Störung der Erregungsbildung und -ausbreitung, Wandverdickung, abnorme Textur des Myokards, linksventrikuläre Hypertrabekulierung, Dilatation der Herzhöhlen mit/ohne sekundärer Klappeninsuffizienz, Reduktion der Koronarreserve, intrakardiale Thrombusbildung, Endo-/Myokardfibrose, regionale Wandbewegungsstörung und systolische und/oder diastolische Funktionsstörung mit/ohne Herzinsuffizienz. Herzbeteiligung wurde bisher bei Dystrophinopathien, Emery-Dreifuss-Muskeldystrophie, fazioskapulohumeraler Muskeldystrophie, Sarcoglycanopathien, kongenitaler Muskeldystrophie Fukuyama, myotoner Dystrophie Typ 1 und 2, Glykogenose Typ II, III, IV, VII und IX, Carnitinmangel, Myoadenylat-Deaminase-Mangel, Acyl-CoA-Dehydrogenase-Mangel, lysosomaler Glykogen-Speicherkrankheit, Mitochondriopathien, Desmin-Myopathie, Nemalin-Myopathie, Central Core-Krankheit, kongenitaler Fasertypen-Dysproportion, Barth-Syndrom, McLeod-Syndrom und Bethlem-Myopathie beschrieben. Herzbeteiligung bei Myopathien kann über Monate oder Jahre progredient verlaufen oder auch akut auftreten bzw. sich bis hin zum kardialen Notfall verschlechtern. Die Therapie der Herzbeteiligung richtet sich nach den spezifischen kardialen Abnormitäten und umfaßt Digitalis, Diuretika, ACE-Hemmer, Kalziumantagonisten, Amiodaron, Betablocker, L-Carnitin, Antikoagulation, Kardioversion, Schrittmacher, Defibrillator, Hochfrequenz-Katheter-Ablation und die Herztransplantation. Generell sollten Myopathie-Patienten kardiologisch untersucht werden, sobald die neurologische Diagnose feststeht, da eine suffiziente kardiale Therapie die Herzbeteiligung bei Myopathien positiv beeinflußt. Ein kardiologisches Follow-up ist angezeigt, wenn die Herzbeteiligung klinisch manifest wird bzw. bei rascher Progredienz.

  11. Herzbeteiligung bei Myopathien

    Directory of Open Access Journals (Sweden)

    Finsterer J

    2001-01-01

    Full Text Available Herzbeteiligung bei Patienten mit Myopathien wird zunehmend häufiger diagnostiziert. Sie manifestiert sich bei diesen Patienten als Störung der Erregungsbildung und -ausbreitung, Wandverdickung, abnorme Textur des Myokards, linksventrikuläre Hypertrabekulierung, Dilatation der Herzhöhlen mit/ohne sekundärer Klappeninsuffizienz, Reduktion der Koronarreserve, intrakardiale Thrombusbildung, Endo-/Myokardfibrose, regionale Wandbewegungsstörung und systolische und/oder diastolische Funktionsstörung mit/ohne Herzinsuffizienz. Herzbeteiligung wurde bisher bei Dystrophinopathien, Emery-Dreifuss-Muskeldystrophie, fazioskapulohumeraler Muskeldystrophie, Sarcoglycanopathien, kongenitaler Muskeldystrophie Fukuyama, myotoner Dystrophie Typ 1 und 2, proximal myotoner Myopathie, Glykogenose Typ II, III, IV, VII und IX, Carnitinmangel, Myoadenylat-Deaminase-Mangel, Acyl-CoA-Dehydrogenase-Mangel, lysosomaler Glykogen-Speicherkrankheit, Mitochondriopathien, Desmin-Myopathie, Nemalin-Myopathie, Central Core-Krankheit, kongenitaler Fasertypen-Dysproportion, Barth-Syndrom, McLeod-Syndrom und Bethlem-Myopathie beschrieben. Herzbeteiligung bei Myopathien kann über Monate oder Jahre progredient verlaufen oder auch akut auftreten bzw. sich bis hin zum kardialen Notfall verschlechtern. Die Therapie der Herzbeteiligung richtet sich nach den spezifischen kardialen Abnormitäten und umfaßt Digitalis, Diuretika, ACE-Hemmer, Kalziumantagonisten, Amiodaron, Betablocker, L-Carnitin, Antikoagulation, Kardioversion, Schrittmacher, Defibrillator, Hochfrequenz-Katheter-Ablation und die Herztransplantation. Generell sollten Myopathie-Patienten kardiologisch untersucht werden, sobald die neurologische Diagnose feststeht, da eine suffiziente kardiale Therapie die Herzbeteiligung bei Myopathien positiv beeinflußt. Ein kardiologisches Follow-up ist angezeigt, wenn die Herzbeteiligung klinisch manifest wird bzw. bei rascher Progredienz.

  12. Acidification of primary sludge to improve enhanced biological phosphate removal and denitrification; Versaeuerung von Primaerschlamm zur Unterstuetzung der vermehrten biologischen Phosphorelimination und der Denitrifikation

    Energy Technology Data Exchange (ETDEWEB)

    Teichgraeber, B. [Emschergenossenschaft und Lippeverband, Essen (Germany); Becker, A.E. [Emschergenossenschaft und Lippeverband, Essen (Germany); Frei, L. [Emschergenossenschaft und Lippeverband, Essen (Germany)

    1995-06-01

    Hydrolysing primary sludge is an important tool to enhance the denitrification and biological phosphorus removal process in wastewater treatment. In laboratory scale and full scale tests the influenct COD of the biological treatment step could be enlarged by 10-15%. Additional COD mostly consisted of VFA`s. (orig.) [Deutsch] Die Versaeuerung von Primaerschlamm ist eine wichtige Massnahme zur Unterstuetzung der Denitrifikation und der vermehrten biologischen P-Elimination auf Klaeranlagen. In Laborversuchen und auf grosstechnischen Anlagen wurde gezeigt, dass der CSB im Zulauf zur biologischen Reinigungsstufe um 10-15% in Form von leicht abbaubaren Carbonsaeuren erhoeht werden kann. (orig.)

  13. (Biological dosimetry)

    Energy Technology Data Exchange (ETDEWEB)

    Preston, R.J.

    1990-12-17

    The traveler attended the 1st International Conference on Biological Dosimetry in Madrid, Spain. This conference was organized to provide information to a general audience of biologists, physicists, radiotherapists, industrial hygiene personnel and individuals from related fields on the current ability of cytogenetic analysis to provide estimates of radiation dose in cases of occupational or environmental exposure. There is a growing interest in Spain in biological dosimetry because of the increased use of radiation sources for medical and occupational uses, and with this the anticipated and actual increase in numbers of overexposure. The traveler delivered the introductory lecture on Biological Dosimetry: Mechanistic Concepts'' that was intended to provide a framework by which the more applied lectures could be interpreted in a mechanistic way. A second component of the trip was to provide advice with regard to several recent cases of overexposure that had been or were being assessed by the Radiopathology and Radiotherapy Department of the Hospital General Gregorio Maranon'' in Madrid. The traveler had provided information on several of these, and had analyzed cells from some exposed or purportedly exposed individuals. The members of the biological dosimetry group were referred to individuals at REACTS at Oak Ridge Associated Universities for advice on follow-up treatment.

  14. THERMOLUMINESCENT DOSIMETRY

    African Journals Online (AJOL)

    2005-10-20

    Oct 20, 2005 ... abo area of the city has the least radiation dose rate while Obantoku area has the upper limit. aking this as ... 'n Abeokuta. eywords: Environmental radiation, thermoluminescent dosimetry, Abeokuta, outdoor ... Both 238U and 232Th have long decay series with ... effects of radiation exposure (Hanson and.

  15. THERMOLUMINESCENT DOSIMETRY

    African Journals Online (AJOL)

    2005-10-20

    Oct 20, 2005 ... abo area of the city has the least radiation dose rate while Obantoku area has the upper limit. aking this as ... “n Abeokuta. eywords: Environmental radiation, thermoluminescent dosimetry, Abeokuta, outdoor ... Both 238U and 232Th have long decay series with ... effects of radiation exposure (Hanson and.

  16. Neuroimaging bei Schlaganfall

    Directory of Open Access Journals (Sweden)

    Nasel Ch

    2013-01-01

    Full Text Available Während zunächst die Differenzialdiagnosen des Schlaganfalls erfasst werden sollten, wurde sehr bald das Neuroimaging in den Dienst der Behandlung der akuten Ischämie gestellt. Hier kommt der neuroradiologischen Bildgebung eine besondere Rolle zu, da zunehmend die Auswahl von Patienten für eine bestimmte Therapie von der Bildgebung abhängt. Der Verlauf von zerebralen Ischämien ist, bedingt durch stark variierende Faktoren wie Kollateralisation, frühe Rekanalisation etc., sehr unterschiedlich. Die multimodale MR- und CTBildgebung, welche eine Kombination aus konventioneller Bildgebung des Gehirns, angiographischen Verfahren und funktionellen Messungen, wie z. B. Perfusionsmessungen, darstellt, kann jede Ischämie sehr genau charakterisieren. Wichtig ist dabei ein klares Interpretationskonzept. Bei Patienten, deren Symptombeginn eindeutig innerhalb der letzten 3–4,5 h liegt, kann die Nativ- CT, am besten in Kombination mit der CTA, als ausreichend zur Durchführung der anerkannten systemischen i.v.-Lyse sowie zur Feststellung eines Gefäßverschlusses, der einer weiteren Behandlung bedarf, angesehen werden. Im Zeitfenster 4,5 h, bei unklarem Zeitfenster oder nach frustraner i.v.-Lyse, ist, insbesondere bei einem im Weiteren geplanten endovaskulären Eingriff, die multimodale MRI mit Anwendung des „Mismatch-match“-Konzepts zwischen diffusionsgewichtetem MRI und Perfusions-MRI jedenfalls die Methode der ersten Wahl. Steht diese nicht zur Verfügung, kann alternativ das multimodale CT eingesetzt werden.

  17. Dosimetry Service

    CERN Multimedia

    Dosimetry Service

    2005-01-01

    Please remember to read your dosimeter every month at least once and preferably during the first week. A regular read-out is indispensable in order to ensure a periodic monitoring of the personal dose. You should read your dosimeter even if you have not visited the controlled areas. If you still have the old dosimeter (film badge), please send it immediately for evaluation to us (Bdg 24 E-011). After January 2005 there will be no developing process for the old film system. Information for Contractors: Please remember also to bring the form ‘Confirm Reception of a CERN Dosimeter' signed with ‘Feuille d'enregistrement du CERN'. Without these forms the dosimeter cannot be assigned. Thank you for your cooperation. Dosimetry Service Tel 767 2155 http://cern.ch/rp-dosimetry

  18. Radiation dosimetry.

    OpenAIRE

    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.

  19. Topics in radiation dosimetry radiation dosimetry

    CERN Document Server

    1972-01-01

    Radiation Dosimetry, Supplement 1: Topics in Radiation Dosimetry covers instruments and techniques in dealing with special dosimetry problems. The book discusses thermoluminescence dosimetry in archeological dating; dosimetric applications of track etching; vacuum chambers of radiation measurement. The text also describes wall-less detectors in microdosimetry; dosimetry of low-energy X-rays; and the theory and general applicability of the gamma-ray theory of track effects to various systems. Dose equivalent determinations in neutron fields by means of moderator techniques; as well as developm

  20. Operative Revaskularisation bei Diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Hausmann H

    2003-01-01

    Full Text Available Patienten mit KHK und Diabetes mellitus haben sowohl bei interventioneller als auch bei chirurgischer Koronarrevaskularisation ein erhöhtes Mortalitätsrisiko. Allerdings ist nach chirurgischer Revaskularisation vor allem die Rate an notwendigen Reinterventionen wesentlich geringer als nach PTCA. Gegenwärtig liegen keine Ergebnisse über den Langzeitverlauf nach Stentimplantation vor. Außerdem ist das Risiko für einen Diabetiker mit KHK, nach einer Bypassoperation an einem Myokardinfarkt zu versterben, deutlich geringer als nach PTCA. Die Bypassoperation mit Sternotomie trägt allerdings bei Diabetikern ein erhöhtes Risiko für die Entwicklung einer postoperativen Mediastinitis, vor allem dann, wenn bei "totaler arterieller" Revaskularisation beide Aa. mammariae verwendet werden. Deshalb sollte bei Diabetikern zur chirurgischen Revaskularisation die A. mammaria nur einseitig genutzt werden. Prä- und perioperativ ist auf eine besonders sorgfältige Blutzuckereinstellung zu achten. Verkalkungen der herznahen Gefäße, wie z. B. der Aorta ascendens und der Karotiden, müssen präoperativ abgeklärt werden. Die Operation ist möglichst schonend durchzuführen, die Wundfläche sollte minimiert werden. Reexplorationen sind unbedingt zu vermeiden. Bei Beachtung dieser Richtlinien sind auch bei Patienten mit KHK und Diabetes mellitus sehr gute chirurgische Revaskularisationsergebnisse zu erreichen.

  1. Possibilities under the `Kreislaufwirtschaft- und Abfallgesetz` for the recycling or for energy generation from waste with a high calorific value having undergone mechanical-biological conditioning; Moeglichkeiten der energetischen und stofflichen Verwertung von heizwertreichen Reststoffen aus der mechanisch-biologischen Restabfallbehandlung im Rahmen des Kreislaufwirtschafts- und Abfallgesetzes

    Energy Technology Data Exchange (ETDEWEB)

    Franke, J.; Fricke, K. [Ingenieurgemeinschaft Witzenhausen Fricke und Turk GmbH, Witzenhausen (Germany)

    1998-12-31

    This (partial) project has the following aims: to describe comprehensively the possibilities for the recycling, or generation of energy from, waste with a high calorific value having undergone mechanical-biological conditioning; further, to formulate demands regarding the quality of the separated partial fractions. This basic study takes all relevant, commercial thermal processes into account (power plants, cement works, blast furnaces, etc.). Furthermore, the question is investigated of whether the thermal waste processing plants in the area of the Suedhessische Arbeitsgemeinschaft Abfall (SAGA) are suitable for waste utilization. An environmental compatibility statement is made, and the economic and legal boundary conditions are studied. (orig.) [Deutsch] Ziel des (Teil-)Forschungsvorhabens soll es sein, die Moeglichkeiten der energetischen und stofflichen Verwertung heizwertreicher Abfaelle aus der mechanisch-biologischen Restabfallbehandlung umfassend darzustellen und die Anforderungen an die Qualitaet der abgretrennten Teilfraktionen zu formulieren. Bei der Grundlagenermittlung sollen alle relevanten auf dem Markt angebotenen thermischen Verfahren (Kraftwerke, Zementwerke, Hochoefen usw.) mit einbezogen werden. Weiterhin sollen die im SAGA-Gebiet (Suedhessische Arbeitsgemeinschaft Abfall) vorhandenen thermsichen Anlagen auf ihre Eignung zur energetischen bzw. stofflichen Verwertung hin ueberprueft werden. Neben der Bewertung der Umweltvertraeglichkeit werden die oekonomischen und rechtlichen Rahmenbedingungen untersucht. (orig.)

  2. Risikostratifizierung bei akuten Koronarsysdromen

    Directory of Open Access Journals (Sweden)

    Traindl O

    2000-01-01

    Full Text Available Unter dem Begriff der akuten Koronarsyndrome werden die instabile Angina pectoris, nichttransmurale (non-Q-wave Infarkte und transmurale Myokardinfarkte sowie der plötzliche Herztod (Sudden cardiac death zusammengefaßt. Zur Diagnose und Riskoabschätzung werden neben der Klinik des Patienten das EKG und biochemische Marker herangezogen. Die Einteilung nach Braunwald erlaubt heute eine bessere Quantifizierung der individuellen klinischen Beschwerden. Das EKG dient nicht nur zur Diagnostik bei Aufnahme, sondern erlaubt auch Rückschlüsse auf die Langzeitprognose der Patienten. Biochemische Marker ergänzen das nicht immer eindeutige EKG. Die bekannten Enzyme CK und CKMB werden durch die Troponine T und I ergänzt. Diese erfassen bereits wesentlich kleinere myokardiale Läsionen. Die Rolle des Akutphasenproteins CRP als Marker wird derzeit ausführlich untersucht.

  3. Thrombolyse bei Pulmonalembolie

    Directory of Open Access Journals (Sweden)

    Kasper W

    2003-01-01

    Full Text Available Die Lungenembolie ist eine gutartige Erkrankung, wenn sie rechtzeitig entdeckt und effektiv mit Antikoagulanzien behandelt wird. Das Rechtsherzversagen ist die Todesursache bei Lungenembolie. Die Rechtsherzinsuffizienz ist abhängig vom Ausmaß der embolischen Obstruktion der Lungenstrombahn, vom Grad der kardiopulmonalen Vorschädigung und vom Ausmaß der Restthromben in der periphervenösen Zirkulation als Risikofaktor für eine Rezidivembolie. Das Auftreten einer rechtsventrikulären Dysfunktion oder einer Troponin T/I-Erhöhung ist von prognostischer Bedeutung. Für gewöhnlich ist die Prognose während des Krankenhausaufenthaltes gut, wenn keiner der beiden Parameter beobachtet wird. Die thrombolytische Therapie der Lungenembolie ist den Patienten mit hämodynamischer Instabilität vorbehalten. Die klinische Unsicherheit, ob auch Patienten mit submassiver Lungenembolie von einer Thrombolyse profitieren, erklärt sich aus der einzigartigen Beziehung zwischen der embolischen Obstruktion der Lungenstrombahn und der daraus resultierenden Nachlasterhöhung für den rechten Ventrikel. Innerhalb eines engen Bereichs (Miller-Index 17 geht die rechtsventrikuläre Dysfunktion in ein Rechtsherzversagen über. Diese Übergangsphase kann schon durch eine geringe Zunahme der embolischen Obstruktion ausgelöst werden und ist intraindividuell nicht vorhersagbar. Kürzlich wurde eine randomisierte Therapiestudie bei Patienten mit submassiver Lungenembolie durchgeführt, die eine thrombolytische Behandlung gegen eine alleinige Heparintherapie verglich. Die Studie läßt den Schluß zu, daß Patienten mit einer rechtsventrikulären Dysfunktion und einem niedrigen Blutungsrisiko ebenfalls von einer Thrombolyse im Krankheitsverlauf profitieren, obwohl sich kein Unterschied hinsichtlich der Mortalität ergab.

  4. Die Bandscheibenprothese bei schmerzhafter Diskusdegeneration

    Directory of Open Access Journals (Sweden)

    Ogon M

    2004-01-01

    Full Text Available Bandscheibenprothesen sind indiziert bei Patienten mit einer schmerzhaften Bandscheibendegeneration, einer sogenannten DDD (degenerative disc disease, bei gut erhaltenen Facettengelenken. Kontraindikationen stellen eine Instabilität, eine Spondylarthrose, eine spinale Stenose und eine Osteoporose dar. Bei 19 Patienten mit einem Follow-up von mindestens 12 Monaten fand sich eine durchschnittliche Verbesserung des Oswestry Disability Index von präoperativ 50,8 auf 19,8. Der SF-36 Score zur Erfassung der Lebensqualität besserte sich von 31,5 auf 48,8 (Physical Component Summary Score bzw. von 37,8 auf 44,5 (Mental Component Summary Score im 1-Jahres-Follow-up. Nachhaltige Komplikationen traten nicht auf. Bandscheibenprothesen können heute bei Patienten mit therapieresistenten Kreuzschmerzen als gute Alternative zu einer Wirbelfusion angesehen werden.

  5. Dosimetry for radiation processing

    DEFF Research Database (Denmark)

    Miller, Arne

    1986-01-01

    During the past few years significant advances have taken place in the different areas of dosimetry for radiation processing, mainly stimulated by the increased interest in radiation for food preservation, plastic processing and sterilization of medical products. Reference services both...... and sterilization dosimetry, optichromic dosimeters in the shape of small tubes for food processing, and ESR spectroscopy of alanine for reference dosimetry. In this paper the special features of radiation processing dosimetry are discussed, several commonly used dosimeters are reviewed, and factors leading...

  6. Schrittmachertherapie bei Vorhofflimmern

    Directory of Open Access Journals (Sweden)

    Zweng A

    2006-01-01

    Full Text Available Vorhofflimmern ist die häufigste kardiale Rhythmusstörung, die aufgrund unserer alternden Gesellschaft eine steigende Inzidenz zeigt und zunehmend Ursache für Hospitalisierung und Mortalität ist. Herzschrittmacher werden beim Vorhofflimmern einerseits zur Überbrückung bradykarder Phasen eingesetzt (VVI-Modus, andererseits wurde nachgewiesen, daß durch sogenanntes physiologisches Pacing (Vorhofstimulation – AAI-Modus oder häufiger Zweikammersysteme – DDD-Modus im Vergleich zur Einkammerstimulation (VVI-Modus das Auftreten von Vorhofflimmern signifikant reduziert werden kann. In den letzten Jahren wurden Schrittmacher zunehmend aktiv zur Reduktion der Vorhofflimmerlast bei paroxysmalem Vorhofflimmern eingesetzt. Aufgrund der Ergebnisse der bisher durchgeführten Studien ist noch nicht geklärt, welcher Algorithmus (permanente oder intermittierende atriale Überstimulation, antitachykardes Pacing den größten Vorteil zeigt. Weiters wurden alternative Sondenpositionen im Vorhof, Multi-Site-Pacing bzw. biatriales Vorhofpacing zur Reduktion der Vorhofflimmerlast untersucht. Auch hier fehlen noch konsistente Daten großer randomisierter Studien, sodaß heute noch keine Indikation zum routinemäßigen Einsatz dieser Techniken besteht.

  7. Interventionelle Therapiestrategien bei Aortenerkrankungen

    Directory of Open Access Journals (Sweden)

    Divchev D

    2015-01-01

    Full Text Available Endovaskuläre Therapiestrategien (EVAR mit Implantation von Stentgrafts im Bereich der Aorta thoracalis descendens und der thorakoabdominellen Aorta stellen eine alternative und etablierte Therapieoption bei verschiedenen Krankheitsbildern der Aorta dar. Hierzu zählte primär die Korrektur von Aneurysmata der Aorta thoracalis descendens (TEVAR und die Behandlung der Aortenisthmusstenose, mit nunmehr auch Ausweitung der Einsatzgebiete auf die komplizierte Typ-B-Dissektion, Pseudoaneurysmata der Aorta, das penetrierende Aortenulkus, die traumatische Aortendissektion und auf Pathologien mit Einbezug des Aortenbogens. Entscheidende Vorteile der interventionellen Therapie gegenüber dem offen-chirurgischen Vorgehen sind die Vermeidung von ausgedehnten invasiven Thorakotomien bis hin zu Zwei- Höhlen-Eingriffen, kürzeren postprozeduralen Erho lungszeiten sowie weniger Blutungs komplikationen und geringerer Rate an ischämischen Kom plikationen von Viszera, Niere und Rückenmark [1]. Die vorliegende Übersichtsarbeit bezieht sich vorwiegend auf den Einsatz des Aortenstentings für die Pathologien des thorakalen Aortenaneurysmas und der Varianten der Aortendissektion als thorakales endovaskuläres Aortenreparaturverfahren (TEVAR.

  8. Off-air treatment in waste treatment systems and landfills - consequences for practical operation. 62. information meeting of ANS e.V.; Abluftbehandlung bei MBA und Deponiebetrieb - Konsequenzen fuer die Praxis. 62. Informationsgespraech des ANS e.V.

    Energy Technology Data Exchange (ETDEWEB)

    Fricke, K.; Burth, M.; Dichtl, N.; Wallmann, R. (eds.)

    2001-07-01

    The new German Landfill Ordinance of 1 March 2001 specifies the requirements on construction and operation of mechanical-biological waste treatment plants and landfills as well as the continued operation of existing landfills. The conference provided current information of R + D projects as well as practical experience in Austria and Germany, with particular regard to the issues of off-air emissions and landfilling. [German] Seit dem 1. Maerz 2001 ist die Artikelverordnung rechtswirksam. Sie enthaelt Anforderungen an den Bau und Betrieb von mechanisch-biologischen Restabfallbehandlungsanlagen und Deponien. Die Abfallablagerungsverordnung hat darueber hinaus weitreichende Konsequenzen fuer die Betriebsdauer bestehender Deponien. Ziel der Tagung ist es, aktuelle Informationen aus laufenden Forschungs- und Entwicklungsvorhaben sowie Erfahrungen bei der praktischen Umsetzung zu praesentieren, die insbesondere zu den Themenkomplexen Abluftemissionen und Deponierung zur Zeit in Oesterreich und Deutschland vorliegen. (orig.)

  9. Syntaktische Störungen bei Aphasie

    OpenAIRE

    Penke, Martina

    2013-01-01

    1 Einleitung 2 Syntaktische Beeinträchtigung bei Broca-Aphasie 3 Syntaktische Beeinträchtigung bei Wernicke-Aphasie 4 Eine Charakterisierung der syntaktischen Beeinträchtigung bei Broca- und Wernicke-Aphasie 5 Resümee 6 Literatur

  10. Monitoring bei Vorhofflimmern

    Directory of Open Access Journals (Sweden)

    Martinek M

    2011-01-01

    Full Text Available Einleitung: Obwohl Vorhofflimmern (VHF die absolut häufigste Arrhythmie im höheren Lebensalter darstellt, unterschätzen epidemiologische Daten immer noch die Prävalenz der Erkrankung, da adäquate Monitordaten aus größeren Populationen fehlen. Symptomatisches VHF ist nur die Spitze des Eisbergs, da VHF-Episoden in bis zu 90 % asymptomatisch verlaufen. Um dieser großen Anzahl asymptomatischer Episoden und der resultierenden Morbidität (Insult, Herzinsuffizienz und Mortalität Herr zu werden, ist der Einsatz verbesserter Monitoringtechnologien in einer größeren Patientengruppe mit erhöhtem Risiko zu fordern. Nicht-invasives Monitoring: Hier stehen für das Monitoring von VHF-Standard-EKG, Holter- EKGs, Eventrecorder oder transtelefonisches Monitoring zur Verfügung. Ein Großteil der Diagnostik wird aktuell mit einzelnen EKGs oder kurzen Monitoringperioden (24–48-Stunden-Langzeit- EKG durchgeführt, da die Kapazität an längeren Holter-Methoden über 7–30 Tage sehr beschränkt ist. Neuere Methoden könnten hier die Kapazitäten durch automatische Detektionsalgorithmen und „Outsourcing“ aus dem Krankenhaus erhöhen. Invasives Monitoring: Als Goldstandard für das Monitoring von VHF sind sicherlich implantierte Schrittmacher- oder ICDAggregate mit entsprechender Möglichkeit zur Vorhofarrhythmiedetektion anzusehen. Über die Daten dieser Geräte konnten wertvolle, neue Erkenntnisse über Symptomatik, Akut- und Langzeitverlauf sowie Effizienz verschiedener Therapien gewonnen werden. Für Patienten ohne Indikation zur Device-Therapie stehen seit Kürzerem implantierbare Loop-Recordersysteme mit speziellen Softwarealgorithmen zur atrialen Arrhythmiedetektion als permanente Überwachungsmöglichkeit zur Verfügung. Erste Studiendaten ergaben eine durchaus beachtliche Sensitivität von 96,1 % bei einer Spezifität von 85,4 % für die Vorhofflimmerdetektion. Zusammenfassung und Zukunftsperspektiven: Für eine korrekte Diagnostik und

  11. Effects of platinum in biological systems - toxicology and pharmaceutical applications; Wirkungen von Platin in biologischen Systemen - Toxikologie und pharmazeutische Anwendung

    Energy Technology Data Exchange (ETDEWEB)

    Nachtigall, D. [Fraunhofer-Institut fuer Toxikologie und Aerosolforschung, Hannover (Germany)

    1997-12-31

    The title of this lecture has intentionally been worded rather vaguely with ``biological systems`` to do justice to the fact that there are meanwhile extensive data available on diverse levels of the toxicology and structure-effect relationships of some platinum compounds. These range from epidemiological descriptions over toxicity studies to molecular biological reaction mechanisms. Any discussion on the toxicity of a substance implies that the substance poses a direct or indirect hazard to humans. In the case of platinum and its compounds there are three main categories of exposure: platinum production including workplaces in the platinum processing industries; clinical treatment with antineoplastic platinum-containing agents; and, finally, the environment, where platinum levels are known to be rising since some years. The association between these exposures becomes clear when one considers the platinum pollution caused by automobile catalytic converters, hospital effluents, and by platinum-containing industrial products in the widest sense. [Deutsch] Der Titel des Vortrages ist mit `biologischen Systemen` sehr allgemein gehalten, da ueber die Toxikologie und die Struktur-Wirkungsbeziehungen einiger Platinverbindungen auf den verschiedensten Ebenen umfangreiche Daten vorliegen. Diese reichen von epidemiologischen Beschreibungen ueber Toxizitaetsstudien bis hin zu molekularbiologischen Reaktionsmechanismen. Die Diskussion um die Toxizitaet von Substanzen impliziert immer die direkte oder indirekte Gefaehrdung des Menschen. Im Falle des Platins und seiner Verbindungen existieren drei wesentliche Expositionsbereiche: Die Platingewinnung sowie die Arbeitsplaetze in der Platin verarbeitenden Industrie, die klinische Behandlung mit antineoplastischen Platinwirkstoffen und schliesslich die Umwelt, in der seit einigen Jahren ansteigende Platinkonzentrationen verzeichnet werden. Die Verbindung zwischen diesen Bereichen wird deutlich, wenn man die Platinimmissionen durch

  12. Dosimetry service removal

    CERN Multimedia

    Safety Commission

    2010-01-01

    Dear personal dosimeter user, Please note that the Dosimetry service has moved in building 55, the service is now located in the main floor: 55-R-004. Main floor instead of second floor. On your right hand when accessing in the building. Thank you Dosimetry Service

  13. Androgenmangel bei Frauen: Wann klinisch relevant?

    Directory of Open Access Journals (Sweden)

    Jaursch-Hancke C

    2011-01-01

    Full Text Available Androgene haben bei Männern und Frauen Einfluss auf Muskulatur, Fettverteilung sowie Sexualität, allgemeine Leistungsfähigkeit und Wohlbefinden. Bei Frauen sind im Unterschied zu Männern Symptome des Hypogonadismus weniger klar definiert und es gibt derzeit keine Messparameter, die eine Androgenmangelsituation bei Frauen sicher erfassen. Der Begriff "Hypoactive Sexual Desire Disorder" (HSDD hat sich für die klinische Symptomatik durchgesetzt. Zu gesicherten Androgenmangelzuständen gehören die chirurgische Menopause, der Panhypopituitarismus, der Morbus Addison, die natürliche Menopause und verschiedene Medikamente, die zu einer Androgensupprimierung führen. Eine Testosteronsubstitution ist nur sinnvoll bei klinischer Symptomatik (HSDD. Die Patientinnen müssen darauf hingewiesen werden, dass es sich um eine noch nicht etablierte Therapie handelt und Langzeitdaten somit fehlen. Bei richtiger Indikationsstellung ist der Erfolg der Therapie aber oftmals überzeugend.

  14. Leberversagen bei Sepsis und Multiorganversagen

    Directory of Open Access Journals (Sweden)

    Kapral C

    2005-01-01

    Full Text Available Eine Störung der Leberfunktion wird bei etwa 20–25% der Patienten mit Organversagen im Rahmen einer schweren Entzündungsreaktion beobachtet. Obwohl der klinische Parameter hierfür – der Anstieg des Bilirubins – in der Regel erst nach Funktionsstörungen anderer Organe auftritt, zeigen sehr sensitive Nachweismethoden einer hepatalen Dysfunktion wie die Indozyangrünclearance, daß die Leberbeteiligung ein sehr frühes Ereignis darstellt. Ursache für die Funktionseinschränkung der Leber sind vor allem Zytokine, die großteils direkt in der Leber selbst auf die verschiedenen Stimuli (Endotoxine, Hypoxie usw. freigesetzt werden. Spezifische Therapiemaßnahmen zur Verbesserung der Leberfunktion stehen dem Kliniker derzeit nicht zur Verfügung. Es gilt auch hier der Grundsatz, daß durch eine frühzeitige Herdsanierung und effektive Kreislauftherapie die Zytokinaktivierung möglichst gering gehalten werden soll, um damit auch Organtoxizitäten zu vermindern. Die zur Verfügung stehenden, kreislaufaktiven Substanzen zeigen eine individuell nur schwer voraussagbare, sehr unterschiedliche Wirkung auf Kreislauf und Funktion der Leber. Einzig Adrenalin dürfte aufgrund der vorliegenden Untersuchungen eine eher ungünstige Wirkung haben und sollte daher nicht zur Anwendung kommen. In der letzten Zeit konnten jedoch durch neue Maßnahmen erste klinische Erfolge nachgewiesen werden, bzw. im Tierexperiment eine Verbesserung der Leberfunktion beobachtet werden. So konnte durch Normalisierung der Blutzuckerkonzentration bei Patienten mit Sepsis eine Verbesserung der Mortalität und auch Verbesserung der mitochondrialen Funktion von Leberzellen beobachtet werden. Durch die Gabe von N-Acetylcystein wurde in Studien an kleinen Fallzahlen eine günstige Wirkung beobachtet, größere Studien werden hier Klarheit schaffen. Ebenfalls in klinischer Erprobung ist die orale Gabe von Gallensäuren, die den Gallensäuregehalt des Darmes erhöhen und damit die

  15. Die Dankesrede bei der Preisverleihung

    Directory of Open Access Journals (Sweden)

    Elenmari Pletikos Olof

    2012-12-01

    Full Text Available Festliche Preisverleihungen sind Gelegenheiten, bei denen von den Preisträgerneine kurze Rede erwartet wird. Obwohl die Dankesrede eine kleinere Randgattung innerhalb des epideiktischen Genres ist, steht sie im Mittelpunkt des Ereignisses. Rhetorikhandbücher geben zahlreiche Ratschläge, wie eine gute Festrede vorbereitet werden soll, um zu unterhalten, zu bewegen und zu belehren. Ziel dieser Untersuchung ist es festzustellen, welche Eigenschaften der Dankesrede die Zuhörer als erwünscht oder unerwünscht wahrnehmen und welche Charakteristika am meisten zur Qualität festlicher Dankesreden beitragen. Das Korpus der gesprochenen Texte bilden 30 Dankesreden anlässlich kroatischer Preisverleihungen in den Bereichen Schauspiel, Sport, Musik, Fernsehen, Literatur und Wirtschaft. Die Audio-Aufnahmen der Dankesreden wurden einer Gruppe von Hörern zur Bewertung in folgenden Kategorien vorgelegt: interessant, geistreich, hoher Sprachstil, feierlich, emotiv, persönlich, originell, bescheiden, vorbereitet und spontan. Zusätzlich wurde zu jeder Rede die offene Frage gestellt, was dem Zuhörer an der Rede gefallen oder nicht gefallen habe. Die Resultate der Perzeptionsanalye lassen erkennen, dass die Interessantheit einer Rede mit der Eigenschaft des Geistreichen, des Originellen, des Emotionalen und des Persönlichen in Verbindung gebracht wird und die Eigenschaft des Festlichen im Wesentlichen nur mit dem hohen Sprachstil und der Vorbereitetheit des Textes korreliert. Einige Eigenschaften können sowohl erwünscht als auch unerwünscht sein, z. B. Dialekt, Persönliches und Kürze. Die besten Dankesreden haben Eigenschaften, die im Grunde schwer miteinander zu verbinden sind: Einerseits soll der Text vorbereitet sein (hoher Stil, Wortwahl, Figuren, Originalität der Geschichte, Humor, andererseits wird bei der Ausführung Spontaneität (Aufrichtigkeit, Emotionalität, Persönlichkeit erwartet.

  16. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    2000-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact their dispatchers to explain their activities for the future, after LEP dismantling in order to be maintained on the regular distribution list at Individual DosimetryWe inform all staff and users under regular dosimetric control that the dosimeters for the monitoring period MAY/JUNE will be available from their usual dispatchers on Tuesday 2 May.Please have your films changed before the 12 May.The colour of the dosimeter valid in is MAY/JUNE is YELLOW.Individual Dosimetry Service will be closed on Friday 28 April.

  17. Nuclear medicine radiation dosimetry

    CERN Document Server

    McParland, Brian J

    2010-01-01

    Complexities of the requirements for accurate radiation dosimetry evaluation in both diagnostic and therapeutic nuclear medicine (including PET) have grown over the past decade. This is due primarily to four factors: growing consideration of accurate patient-specific treatment planning for radionuclide therapy as a means of improving the therapeutic benefit, development of more realistic anthropomorphic phantoms and their use in estimating radiation transport and dosimetry in patients, design and use of advanced Monte Carlo algorithms in calculating the above-mentioned radiation transport and

  18. Status of radiation processing dosimetry

    DEFF Research Database (Denmark)

    Miller, A.

    1993-01-01

    Several milestones have marked the field of radiation processing dosimetry since IMRP 7. Among them are the IAEA symposium on High Dose Dosimetry for Radiation Processing and the international Workshops on Dosimetry for Radiation Processing organized by the ASTM. Several standards have been...... or are being published by the ASTM in this field, both on dosimetry procedures and on the proper use of specific dosimeter systems. Several individuals are involved in this international cooperation which contribute significantly to the broader understanding of the role of dosimetry in radiation processing....... The importance of dosimetry is emphasized in the standards on radiation sterilization which are currently drafted by the European standards organization CEN and by the international standards organization ISO. In both standards, dosimetry plays key roles in characterization of the facility, in qualification...

  19. High frequency electromagnetic dosimetry

    CERN Document Server

    Sánchez-Hernández, David A

    2009-01-01

    Along with the growth of RF and microwave technology applications, there is a mounting concern about the possible adverse effects over human health from electromagnetic radiation. Addressing this issue and putting it into perspective, this groundbreaking resource provides critical details on the latest advances in high frequency electromagnetic dosimetry.

  20. Individual dosimetry service

    CERN Document Server

    2004-01-01

    We inform all staff and users under regular dosimetry control that the dosimeters for the monitoring period JULY-AUGUST 2004 are available from their usual dispatchers. Please have your films changed before the 15 JULY 2004. The color of the dosimeter valid in July-August 2004 is PINK.

  1. Menopausale Hormontherapie (MHT bei internistischen Erkrankungen

    Directory of Open Access Journals (Sweden)

    Birkhäuser M

    2014-01-01

    Full Text Available Postmenopausale Frauen leiden zusätzlich zu klimakterischen Beschwerden oft an internistischen Grundkrankheiten. Daher ist es wichtig zu wissen, wann eine Hormonsubstitution (Menopausale Hormontherapie [MHT] in welcher Form verordnet werden darf, wenn mit nichthormonalen Alternativen keine genügende Besserung erzielt werden kann, und wo eine MHT kontraindiziert ist. Zur Verminderung des Risikos einer MHT bei internistischen Grundkrankheiten gelten folgende Grundregeln: – Beginn der MHT innerhalb des „günstigen Fensters“ ( 60 Jahren resp. innert 10 Jahre ab Menopause, außer bei den Kontraindikationen Angiopathie, Koronaropathie und bei anderen vaskulären Pathologien. – Verwenden der niedrigsten wirksamen Dosis, wenn möglich = 50 μg Östradiol/Tag transdermal resp. = 2 mg Östradiol/Tag peroral. Praktisch alle bekannten Nebenwirkungen der MHT sind dosisabhängig. – Bei alleinigen urogenitalen Symptomen nur vaginal-lokale Östrogengabe einsetzen. – Zahlreiche internistische Krankheiten werden durch Leberfaktoren beeinflusst oder induzieren selbst Veränderungen bestimmter Leberparameter (z. B. Gerinnungsfaktoren, Renin-Angiotensin-Aldosteron-System. Deshalb ist zur Vermeidung eines unerwünschten First-Pass-Effektes eine transdermale Östradiolgabe (Pflaster oder Gel vorzuziehen. – Bei kombinierter MHT soll außer bei speziellen Indikationen ein metabolisch neutrales Gestagen wie Progesteron, Dydrogesteron oder Dienogest gewählt oder Norethisteronacetat transdermal verabreicht werden. Gestagene mit glukokortikoider Partialwirkung wie Medroxyprogesteronacetat sind außer als Kurzzeitgabe zu vermeiden, v. a. bei erhöhtem Thromboserisiko. – Drospirenon besitzt eine antimineralokortikoide Wirkung, die bei erhöhtem Blutdruck gezielt eingesetzt werden kann. – Zyklische Schwankungen der Serumspiegel sind zu vermeiden und deshalb statt einer sequenziellen eine kontinuierlich-kombinierte MHT durchzuführen. Dabei kann das Gestagen auch

  2. The dosimetry of ionizing radiation

    CERN Document Server

    1990-01-01

    A continuation of the treatise The Dosimetry of Ionizing Radiation, Volume III builds upon the foundations of Volumes I and II and the tradition of the preceeding treatise Radiation Dosimetry. Volume III contains three comprehensive chapters on the applications of radiation dosimetry in particular research and medical settings, a chapter on unique and useful detectors, and two chapters on Monte Carlo techniques and their applications.

  3. Therapie bei CED: Aminosalizylate, Steroide und Probiotika

    Directory of Open Access Journals (Sweden)

    Eigner W

    2014-01-01

    Full Text Available Morbus Crohn (MC und Colitis ulcerosa (CU sind die Hauptformen der chronisch entzündlichen Darmerkrankungen (CED. Trotz neuer Therapieansätze in den vergangenen 15 Jahren spielen sowohl Glukokortikosteroide als auch 5-Aminosalizylat- (5-ASA- Präparate weiterhin eine große Rolle in der Behandlung von CED. Beide Wirkstoffgruppen können bei CED entweder topisch oder systemisch appliziert werden. Bei den Steroiden stehen systemisch wirksame Formen und das topisch wirksame Budesonid zur Verfügung. Welches Präparat und in welcher Applikation eingesetzt wird, entscheidet sich durch die Art der Erkrankung, den Befall und die Krankheitsaktivität. Das Probiotikum E. coli Nissle ist eine Alternative zu 5-ASA-Präparaten für die Erhaltung der Remission bei der mild verlaufenden CU.

  4. Neurochirurgische OP-Indikation bei malignen Mediainfarkten

    Directory of Open Access Journals (Sweden)

    Gruber A

    2011-01-01

    Full Text Available Bei Patienten mit malignen Mediainfarkten kann durch dekompressive Hemikraniektomie (DHC die unter konservativem Management bei 80 % liegende Mortalität auf 30 % gesenkt werden. Überleben und gutes neurologisches Outcome nach Mediainfarkt und DHC sind vor allem dann zu erwarten, wenn jüngere Patienten ( 60 Jahre früh ( 48 Stunden nach Symptombeginn zur Operation gelangen. Für 60-jährige Patienten sowie für den Zeitraum 48 Stunden nach Symptombeginn gibt es derzeit keine sicheren Daten und die Entscheidung über eine mögliche Operation muss einzelfallabhängig erfolgen. Die diesen Überlegungen zugrunde liegenden Metaanalysen weisen methodische Probleme, konkret Post-hoc- Subgruppenanalysen (2009 und eine Modifikation des primären Studienendpunkts (2007 auf. Die Grundaussage der Studien und damit die Rationale für DHC bei malignem Mediainfarkt bleiben davon jedoch unberührt.

  5. Quantitative imaging for clinical dosimetry

    Science.gov (United States)

    Bardiès, Manuel; Flux, Glenn; Lassmann, Michael; Monsieurs, Myriam; Savolainen, Sauli; Strand, Sven-Erik

    2006-12-01

    Patient-specific dosimetry in nuclear medicine is now a legal requirement in many countries throughout the EU for targeted radionuclide therapy (TRT) applications. In order to achieve that goal, an increased level of accuracy in dosimetry procedures is needed. Current research in nuclear medicine dosimetry should not only aim at developing new methods to assess the delivered radiation absorbed dose at the patient level, but also to ensure that the proposed methods can be put into practice in a sufficient number of institutions. A unified dosimetry methodology is required for making clinical outcome comparisons possible.

  6. Neutron beam measurement dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Amaro, C.R. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1995-11-01

    This report describes animal dosimetry studies and phantom measurements. During 1994, 12 dogs were irradiated at BMRR as part of a 4 fraction dose tolerance study. The animals were first infused with BSH and irradiated daily for 4 consecutive days. BNL irradiated 2 beagles as part of their dose tolerance study using BPA fructose. In addition, a dog at WSU was irradiated at BMRR after an infusion of BPA fructose. During 1994, the INEL BNCT dosimetry team measured neutron flux and gamma dose profiles in two phantoms exposed to the epithermal neutron beam at the BMRR. These measurements were performed as a preparatory step to the commencement of human clinical trials in progress at the BMRR.

  7. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    2000-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact the Individual Dosimetry Service.We inform all staff and users under regular dosimetric control that the dosimeters for the monitoring period MARCH/APRIL will be available from their usual dispatchers on the third of March 2000.Please have your films changed before the 13th of March.The colour of the dosimeter valid in MARCH/APRIL is BLUE.

  8. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    1999-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact the Individual Dosimetry ServiceWe inform all staff and users under regular dosimetric control that the dosimeters for the monitoring period JANUARY/FEBRUARY will be available from their usual dispatchers on Monday the third of January 2000.Please have your films changed:before the 12 January.The colour of the dosimeter valid in JANUARY/FEBRUARY is WHITE.

  9. Entwicklungstrends bei landwirtschaftlichen Applikationen - ein Zwischenfazit

    Directory of Open Access Journals (Sweden)

    Christa Hoffmann

    2014-10-01

    Full Text Available Globalisierung, volatile Märkte und der vermehrte Rückzug der Agrarpolitik aus der Marktregulierung sorgen dafür, dass die Entscheidungsfindungsprozesse auf landwirtschaftlichen Betrieben an Komplexität zunehmen. Applikationen bieten durch ihre Mobilität und individuellen Ausgestaltungsmöglichkeiten Optionen, um den Landwirt bei seiner täglichen Arbeit zu unterstützen. In diesem Kontext nimmt diese Arbeit eine Bestandsaufnahme und Kategorisierung nativer Applikationen mit landwirtschaftlichem Bezug vor. Die Ergebnisse zeigen unter anderem einen Angebotsschwerpunkt im Produktionszweig Pflanzenbau und bei den Funktionen bestimmte häufig auftretende bedarfsbedingte Kombinationen (z. B. Planung und Analyse.

  10. Vibrant Soundbridge bei Kindern - erste Ergebnisse

    OpenAIRE

    Hey, C; Ernst, B; Leinung, M; Stöver, T

    2012-01-01

    Einleitung: Das Mittelohr-Implantatsystem VIBRANT SOUNDBRIDGE (VSB), Fa. MED-EL GmbH wurde seit 1996 bei erwachsenen Patienten mit konduktiver Hörstörung vielfach erfolgreich implantiert. Seit 2009 ist die VSB auch für Kinder in Europa zugelassen, weltweit jedoch bislang erst bei ca. 100 Kindern eingesetzt, davon nur wenige unter dem 5. Lebensjahr.Material und Methodik: Seit 11/2011 wurden in domo 4 Jungen mit unilateraler Gehörgangsatresie bzw. 1 Mädchen mit bilateraler Gehörgangsatresie (...

  11. Dosimetry: an ARDENT topic

    CERN Multimedia

    CERN Bulletin

    2012-01-01

    The first annual ARDENT workshop took place in Vienna from 20 to 23 November. The workshop gathered together the Early-Stage Researchers (ESR) and their supervisors, plus other people involved from all the participating institutions.   “The meeting, which was organised with the local support of the Austrian Institute of Technology, was a nice opportunity for the ESRs to get together, meet each other, and present their research plans and some preliminary results of their work,” says Marco Silari, a member of CERN Radiation Protection Group and the scientist in charge of the programme. Two full days were devoted to a training course on radiation dosimetry, delivered by renowned experts. The workshop closed with a half-day visit to the MedAustron facility in Wiener Neustadt. ARDENT (Advanced Radiation Dosimetry European Network Training) is a Marie Curie ITN project funded under EU FP7 with €4 million. The project focuses on radiation dosimetry exploiting se...

  12. Radioembolization dosimetry : the road ahead

    NARCIS (Netherlands)

    Smits, Maarten L J; Elschot, Mattijs; Sze, Daniel Y; Kao, Yung H; Nijsen, JFW; Iagaru, Andre H; de Jong, Hugo W A M; van den Bosch, Maurice A A J; Lam, Marnix G E H

    2015-01-01

    Methods for calculating the activity to be administered during yttrium-90 radioembolization (RE) are largely based on empirical toxicity and efficacy analyses, rather than dosimetry. At the same time, it is recognized that treatment planning based on proper dosimetry is of vital importance for the o

  13. Pilzinfektionen des Zentralnervensystems bei immunkompetentem Wirt

    NARCIS (Netherlands)

    K. Tintelnot; G.S. de Hoog; G. Haase

    2014-01-01

    Die Mehrzahl von Pilzinfektionen, die zu mykotischen Tumoren führen und bei Patienten ohne jegliche prädisponierende Vorerkrankung auftreten, wird durch Cryptococcus gattii bzw. C. neoformans oder durch Schwärzepilze, insbesondere durch Cladophialophora bantiana, Ramichloridium mackenziei, Exophiala

  14. Diagnostische Besonderheiten bei der Inkontinenz des Mannes

    Directory of Open Access Journals (Sweden)

    Fischer M

    2004-01-01

    Full Text Available Es gibt 3 Ursachen für die männliche Harninkontinenz: die Detrusorfehlfunktion (drangbedingter Harnverlust bei Blasenreizung; die Obstruktion, meistens durch die Prostata bedingt, welche zur Überlaufinkontinenz führen kann; die (postoperative oder posttraumatische Sphinkterinkompetenz (Schließmuskelläsion mit Stressinkontinenz. Die Aufgabe der Diagnostik ist es, die Ursache(n herauszufinden, teilweise mit therapeutischen Mitteln. In der Stufendiagnostik erfolgt die erste Abklärung beim Facharzt mit Harnanalyse, Restharnbestimmung, Uroflow und je nach Symptomatik sofortiger Endoskopie. Eine alleinige Drangsymptomatik kann medikamentös anbehandelt werden. Die Beseitigung einer Obstruktion muß meist operativ erfolgen, da die medikamentöse Therapie kaum ausreicht. Bei unklaren Befunden bezüglich einer Obstruktion, Therapieresistenz bei Dranginkontinenz, Postprostatektomie-Inkontinenz und bei Verdacht auf neurogene Ursache der Inkontinenz sollte die weitere Abklärung über eine Spezialambulanz großteils inkl. Urodynamik erfolgen (mit Blasendruckmessung, Flow/EMG, Urethradruckmessung und Harnröhrenröntgen. Je nach Ergebnis kann dann eine gezielte Therapie eingeleitet werden.

  15. Schmerz: Symptom, Folge, Behandlung bei Multipler Sklerose

    Directory of Open Access Journals (Sweden)

    Schmidegg S

    2006-01-01

    Full Text Available Schmerz ist ein viel häufigeres Symptom bei Patienten mit Multipler Sklerose als angenommen. In 5,5 % der Patienten ist Schmerz ein vorherrschendes Symptom, entweder alleine oder in Kombination mit anderen Symptomen, z. B. der Spastizität. Häufigste Symptome sind ein zentral neuropathischer Schmerz, die Allodynie und Hyperalgesie sowie Trigeminusneuralgien.

  16. Relocation of Dosimetry Service

    CERN Multimedia

    2007-01-01

    The Dosimetry Service is moving from Building 24 to Building 55 and will therefore be closed on Friday, March 30. From Monday, April 2 onwards you will find us in building 55/1-001. Please note that during that day we might still have some problems with the internet connections and cannot fully guarantee normal service procedures. The service's opening hours and telephone number will not change as a result of the move 8.30 - 12.00, afternoons closed Tel. 72155

  17. INDIVIDUAL DOSIMETRY SERVICE

    CERN Multimedia

    2000-01-01

    Personnel in the distribution groups Aleph, Delphi, L3, Opal who also work for other experiments than at LEP, should contact their dispatchers to explain their activities for the future, after LEP dismantling in order to be maintained on the regular distribution list at Individual Dosimetry ServiceWe inform all staffs and users under regular dosimetric control that the dosimeters for the monitoring period JULY/AUGUST are available from their usual dispatchers.Please have your films changed before the 10th of July.The colour of the dosimeter valid in JULY/AUGUST is PINK.

  18. Effects of temperature, plant configuration and loading on the effluent concentration of biological sewage treatment plants; Einfluss von Temperatur, Anlagenkonfiguration und Auslastung auf die Ablaufkonzentration bei der biologischen Abwasserreinigung

    Energy Technology Data Exchange (ETDEWEB)

    Durth, A.

    2000-07-01

    The design of wastewater treatment plants is generally based on the maximum growth rate of the nitrifiers, which is smaller and shows a stronger dependency on temperature than the growth rate of heterotrophic bacteria. This 'kinetic temperature influence' is usually described by exponential equations with a temperature coefficient {theta}. Using these equations for the design of treatment plants results in large volumes of the aeration basin, followed by high investment cost and consumption of large space. On the other hand, long-term effluent data from various plants reveal a small or even no temperature influence on the effluent concentrations. This effect has to be attributed to other influences, which can only be taken into account by modelling the process as a whole. Therefore, the aim of this thesis is to quantify the temperature influence on the effluent concentration of biological treatment by modelling the entire treatment process. (orig.)

  19. Development of a process for a better biological degradation of dangerous substance by using tensid in the wastewater treatment. Final report; Tensideinsatz - Entwicklung eines Verfahrens zum verbesserten biologischen Abbau gefaehrlicher Stoffe bei der Abwasserreinigung durch Tensideinsatz. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Raebiger, N.; Fischer, U.; Leibfritz, D.

    2001-07-01

    In this Project in an interdisciplinary cooperation the influence of tensides on the performance improvement of biochemical decomposition of persistent substances has been investigated. During the first part of the project (Prof. Raebiger) two continously supplied experimental plants were built. These two plants, using activated sludge from a municipal wastewater treatment plant, were run simultaneously with and without tensides respectively. The investigations show, that the results in regard to the decomposition rate are better from the plant operated with tenside. Also, the decomposition rate in relation to the total solids content has shown to be better in the plant run with tenside in comparison to the plant without tenside. This was especially relevant during simulated malfunctions. In project part II (Prof. Dr. U. Fischer) further investigations into the influence of tensids on the microbial decomposition of pollutants have been conducted using the adapted microorganism cultures taken from the experimental reactors. Investigations using activated sludge flakes and a monoculture in a batchprocess have shown an increased growth in the presence of the investigated tensids. A variation in the pollutant concentration as well as the addition of the tensid Bioversal to the nutrient medias yielded hints for the optimization of the culture conditions. In Part III of the project (Prof. Leibfritz) an extraction process was optimized in order to meet the requirements of the bacteria cultures and the objective of the project. Among other things, the influence of the tensids on the decomposition speed of the pollutants has been demonstrated in the course of this examinations. The findings gathered from this joint project regarding the use of tensids for improved decomposition of persistent substances, particularly during malfunctions and strong changes in the concentration, can be transposed into technical application in the future. (orig.)

  20. Echokardiographie aktuell: Herzinsuffizienz bei mechanischer Aortenklappenprothese

    Directory of Open Access Journals (Sweden)

    Glaser F

    2007-01-01

    Full Text Available bVorgeschichte/bbr Bei einem 75jährigen Patienten wurde vor 10 Jahren eine 4fach-Bypassoperation und ein mechanischer Aortenklappenersatz (Tecna 21 mm bei koronarer Dreigefäßerkrankung und schwerer Aortenstenose durchgeführt. Seit damals ist eine mäßig reduzierte linksventrikuläre Pumpfunktion bekannt, mit einer Auswurffraktion von 40 % und ausgedehnter posterolateraler und lateraler Akinesie (Abb. 1, 2. Als kardiovaskuläre Risikofaktoren liegen ein inzwischen insulinpflichtiger Diabetes, eine Hypertonie und stattgehabter Nikotinabusus vor. Im Jahr 2004 wurde wegen mäßiger Angina pectoris-Beschwerden eine Koronarangiographie durchgeführt, wobei ein Verschluß des LIMA-Bypasses zum LAD und ein Verschluß eines Venenbypasses zu einem marginalen Ast des Ramus circumflexus nachgewiesen wurde. Der LIMA-Verschluß war allerdings nicht sehr bedeutend, da ein gut funktionierender Venenbypass zum Diagonalast auch den peripheren LAD gut mitversorgt. Die therapeutische Konsequenz war konservativ. Die laufenden kardiologischen Kontrollen, einschließlich regelmäßiger Echokardiographie, wurden vom niedergelassenen Internisten durchgeführt. Der echokardiographische Befund hatte sich über die Jahre nicht verändert. Das Management der Risikofaktoren und die Herzinsuffizienztherapie wurden von seiten des Internisten vorbildlich durchgeführt, bis vor kurzem war der Patient mit seiner mäßig eingeschränkten Leistungsfähigkeit zufrieden.br bDas aktuelle kardiale Problem/bbr In den vergangenen Monaten kam es zu zunehmender Herzinsuffizienzsymptomatik mit Müdigkeit und Leistungslimitierung durch Dyspnoe ohne wesentliche Angina pectoris, entsprechend NYHA III–IV. Echokardiographisch fanden wir bezüglich der Linksventrikelfunktion den oben beschriebenen Befund. Von seiten der diastolischen Parameter fand sich ein nach allen Kriterien „restriktives“ Muster entsprechend einem erhöhten linksventrikulären Füllungsdruck (Abb. 3, 4 und dazu

  1. Information from the Dosimetry Service

    CERN Multimedia

    2006-01-01

    Please note the following opening hours of the Service: From 31st July onwards: Every morning from 8:30 to 12:00 The Service is closed in the afternoons. We should like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCTs) must always be returned to the Service after use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel 72155 Bldg. 24 E 011 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  2. Influence of phosphorus elimination on sludge treatment and sludge usage at municipal wastewater treatment plants; Einfluss von P-Eliminierungsverfahren auf Schlammbehandlung und -verwertung bei der kommunalen Abwasserreinigung

    Energy Technology Data Exchange (ETDEWEB)

    Poepel, H.J.; Jardin, N.

    1995-01-01

    .) [Deutsch] Im ersten Teil der Arbeit wird der Einfluss der erhoehten biologischen Phosphorelimination auf den Ueberschussschlammanfall, die Phosphorrueckloesung waehrend der Schlammbehandlung und die daraus resultierende P-Rueckbelastung untersucht. Dazu wurden umfangreiche Versuche im halbtechnischen Massstab mit verschiedenen Eindickungssystemen (Zentrifuge, Siebtrommel und Schwerkrafteindickung) und Stabilisierungsverfahren (anaerob-mesophile und aerob-thermophile Stabilisation) durchgefuehrt. Bei der erhoehten biologischen Phosphorelimination wurde, bedingt durch die Einlagerung von Phosphor in Form von Polyphosphat, ein zusaetzlicher Schlammanfall von etwa 3 g TS/g P gefunden. Alle untersuchten Verfahren der getrennten Ueberschussschlammeindickung verursachten nur eine geringe P-Rueckbelastung. Bei beiden Stabilisierungsverfahren wurde das Polyphosphat vollstaendig hydrolysiert und Phosphat freigesetzt. Durch Ausfaelle von Struvit (Magnesium-Ammonium-Phosphat) und Adsorptionsreaktionen wurde jedoch ein grosser Teil des freigesetzten Phosphats refixiert, so dass die resultierende P-Rueckbelastung meist unter 20% der P-Zulauffracht lag. Auf Basis der durchgefuehrten Versuche wurde ein kinetisches Modell zur Beschreibung von Phosphatrueckloesung und -fixierung entwickelt. Im zweiten Teil der Arbeit wird der Einfluss der chemisch-physikalischen Phosphorelemination auf Schlammanfall und P-Rueckloesung waehrend der Schlammbehandlung untersucht. Dazu wurden Untersuchungen an zwei halbtechnischen Versuchsanlagen durchgefuehrt, von denen eine ohne und die andere mit P-Faellung betrieben wurde. Der Ueberschussschlamm beider Anlagen wurde mit Hilfe der anaerob-mesophilen Stabilisierung anschliessend getrennt ausgefault. Variiert wurden die relativen Faellmittelmenge ({beta}=0,7 bis 2), die P-Konzentration im Zulauf (15 bis 20 mg/l P{sub ges}) und das Schlammalter (4 bis 8 Tage). Die Verwendung von AVR zur Phosphatfaellung fuehrte zu einem zusaetzlichen...

  3. Lipidsenker bei Hypertonie - Was besagt die Evidenz?

    Directory of Open Access Journals (Sweden)

    Marte T

    2004-01-01

    Full Text Available Die Koexistenz von Risikofaktoren für atherosklerotische Prozesse, wie Hypertonie und Hypercholesterinämie, hat einen multiplikativen Effekt auf das Risiko kardiovaskulärer Ereignisse. Bislang wurden relativ wenige spezifische Daten zur Frage der Lipidintervention bei Hypertoniepatienten veröffentlicht. Post-hoc-Subgruppenanalysen der großen randomisierten kontrollierten Studien mit Statinen in der Primär- und Sekundärprävention lassen schließen, daß der relative kardiovaskuläre Benefit einer lipidsenkenden Behandlung bei normotensiven und hypertensiven Patientenpopulationen ähnlich ist. Dem Antihypertensive and Lipid-Lowering Treatment to Prevent Heart Attack Trial (ALLHAT-LLT war es nicht möglich, einen Einfluß einer Statintherapie auf die Gesamtmortalität einer hypertensiven Kohorte zu zeigen. Die schlechte Compliance im Statin-Arm und eine hohe Rate an Statin-Einnahme in der "Kontrollgruppe" waren für dieses negative Ergebnis verantwortlich. Das Anglo-Scandinavian Cardiac Outcomes Trial – Lipid Lowering Arm (ASCOT-LLA untersuchte den Effekt der cholesterinreduzierenden Therapie in der Prävention atherosklerotischer Ereignisse bei Hypertonikern mit Gesamtcholesterinkonzentrationen von 250 mg/dl. Hier war ein Benefit ersichtlich, die absolute Risikoreduktion für diese Patientenpopulation war jedoch gering. Bezüglich der Frage, ob Antihypertensiva einen klinisch signifikanten Effekt auf die Blutfette haben, sind einige Studien durchgeführt worden. Die verfügbaren Daten zeigen aber nur einen marginalen Effekt. Zusammengefaßt sollte die Statintherapie bei gleichzeitig vorhandener Hypertonie vornehmlich in der Sekundärprävention ein integraler Bestandteil der Behandlung sein. In der Primärprävention hingegen sollte die Entscheidung bezüglich Statintherapie vom individuellen Gesamtrisiko abhängig gemacht werden.

  4. Orale Kontrazeptiva und Langzyklus bei Endometriose

    Directory of Open Access Journals (Sweden)

    Göretzlehner G

    2008-01-01

    Full Text Available Die Hormontherapie der Endometriose ist mit GnRH-Analoga, oralen hormonalen Kontrazeptiva (Mikropillen mit einer Ethinylestradiol-Dosis ≤30 µg und einem Gestagen und Gestagenen möglich. Unmittelbar nach der histologischen Sicherung der Diagnose Endometriose sollte mit der Hormontherapie begonnenen werden. Mikropillen können sowohl zyklisch (21/7 Tage, im Langzyklus (84/7– 189/7 Tage oder in kontinuierlicher Langzeiteinnahme angewendet werden. Die klassische zyklische Einnahme der Mikropillen im Rhythmus 21/7 Tage mit 13 Hormonentzugsblutungen pro Jahr und diversen Zusatzblutungen in Form von Spottings und Durchbruchblutungen führt zyklisch immer wieder zur Aktivierung der Gonadotropin-abhängigen Ovarialfunktion mit endogener Steroidbiosynthese. Durch das endogen gebildete Estradiol und die Blutungen werden bei der zyklischen Einnahme der Mikropillen die Endometrioseherde immer wieder stimuliert. Bei der kontinuierlichen Langzeiteinnahme und im Langzyklus wird diese Möglichkeit der Stimulation der Endometriose reduziert oder entfällt gänzlich. Aus diesem Grund wird bei Frauen mit einer Endometriose die kontinuierliche Langzeiteinnahme oder der Langzyklus empfohlen.

  5. Experimentelle erzeugung der immun. Insulitis bei mausen

    Directory of Open Access Journals (Sweden)

    Okada,Soji

    1976-04-01

    Full Text Available Experimentelle Produktion der Immun-Insu1itis wurde aufgrund der aktiven Immunisierung der Mause vom dd-Stamm durch wiederholte Gabe vom rekristallisierten Rinderinsulin im Abstand von 4 Wochen unternommen. Wahrend der Zeitdauer vom 3. Tag bis zur 28. Woche nach der ersten Sensibilisierung wurden serologische sowie histo1ogische Untersuchungen an diesen Tieren vorgenommen. Dabei ergaben sich fo1gende Befunde: (1 Die Immunlnsulitis kam bei allen von 58 Fallen bis zu 16 Wochen nach dem Sensibilisierungsbeginn nicht zur Erscheinung, und trat bei 2 von 8 Fallen erst in der 20. Woche und dann bei 3 von 8 Fallen in der 28. Woche in die Erscheinung. (2 Kein signifikanter Unterschied bestand in Hinsicht des insulinverbindenden Antikorpertiters im Blut zwischen den Fallen mit und ohne Immun-Insulitis in der 20. Woche sowie in der 28. Woche. (3 1m Zeitlauf gab es aber eine gute Koinzidenz zwischen der Entstehung der Immun-Insulitis und der Herabsetzung des Antikorpertiters im Blut. (4 Untersuchungen des Pankreas mit Hi1fe der direkten Fluoreszenz-Antikorpermethode ergaben keine erkennbare spezifische Fluoreszenz innerhalb der Langerhansschen Inseln. Diese Untersuchungsergebnisse liefern der Ansicht einen Beweis, da~ die Insulitis, die fUr den mensch1ichen Diabetes mellitus spezifisch ist, mindestens zum Teil durch einen immuno1ogischen Mechanismus entstehen konnte.

  6. Internal dosimetry technical basis manual

    Energy Technology Data Exchange (ETDEWEB)

    1990-12-20

    The internal dosimetry program at the Savannah River Site (SRS) consists of radiation protection programs and activities used to detect and evaluate intakes of radioactive material by radiation workers. Examples of such programs are: air monitoring; surface contamination monitoring; personal contamination surveys; radiobioassay; and dose assessment. The objectives of the internal dosimetry program are to demonstrate that the workplace is under control and that workers are not being exposed to radioactive material, and to detect and assess inadvertent intakes in the workplace. The Savannah River Site Internal Dosimetry Technical Basis Manual (TBM) is intended to provide a technical and philosophical discussion of the radiobioassay and dose assessment aspects of the internal dosimetry program. Detailed information on air, surface, and personal contamination surveillance programs is not given in this manual except for how these programs interface with routine and special bioassay programs.

  7. Radioembolization Dosimetry: The Road Ahead

    Energy Technology Data Exchange (ETDEWEB)

    Smits, Maarten L. J., E-mail: m.l.j.smits-3@umcutrecht.nl; Elschot, Mattijs [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine (Netherlands); Sze, Daniel Y. [Stanford University School of Medicine, Division of Interventional Radiology (United States); Kao, Yung H. [Austin Hospital, Department of Nuclear Medicine (Australia); Nijsen, Johannes F. W. [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine (Netherlands); Iagaru, Andre H. [Stanford University School of Medicine, Division of Nuclear Medicine and Molecular Imaging (United States); Jong, Hugo W. A. M. de; Bosch, Maurice A. A. J. van den; Lam, Marnix G. E. H. [University Medical Center Utrecht, Department of Radiology and Nuclear Medicine (Netherlands)

    2015-04-15

    Methods for calculating the activity to be administered during yttrium-90 radioembolization (RE) are largely based on empirical toxicity and efficacy analyses, rather than dosimetry. At the same time, it is recognized that treatment planning based on proper dosimetry is of vital importance for the optimization of the results of RE. The heterogeneous and often clustered intrahepatic biodistribution of millions of point-source radioactive particles poses a challenge for dosimetry. Several studies found a relationship between absorbed doses and treatment outcome, with regard to both toxicity and efficacy. This should ultimately lead to improved patient selection and individualized treatment planning. New calculation methods and imaging techniques and a new generation of microspheres for image-guided RE will all contribute to these improvements. The aim of this review is to give insight into the latest and most important developments in RE dosimetry and to suggest future directions on patient selection, individualized treatment planning, and study designs.

  8. Radioembolization dosimetry: the road ahead.

    Science.gov (United States)

    Smits, Maarten L J; Elschot, Mattijs; Sze, Daniel Y; Kao, Yung H; Nijsen, Johannes F W; Iagaru, Andre H; de Jong, Hugo W A M; van den Bosch, Maurice A A J; Lam, Marnix G E H

    2015-04-01

    Methods for calculating the activity to be administered during yttrium-90 radioembolization (RE) are largely based on empirical toxicity and efficacy analyses, rather than dosimetry. At the same time, it is recognized that treatment planning based on proper dosimetry is of vital importance for the optimization of the results of RE. The heterogeneous and often clustered intrahepatic biodistribution of millions of point-source radioactive particles poses a challenge for dosimetry. Several studies found a relationship between absorbed doses and treatment outcome, with regard to both toxicity and efficacy. This should ultimately lead to improved patient selection and individualized treatment planning. New calculation methods and imaging techniques and a new generation of microspheres for image-guided RE will all contribute to these improvements. The aim of this review is to give insight into the latest and most important developments in RE dosimetry and to suggest future directions on patient selection, individualized treatment planning, and study designs.

  9. Hanford internal dosimetry program manual

    Energy Technology Data Exchange (ETDEWEB)

    Carbaugh, E.H.; Sula, M.J.; Bihl, D.E.; Aldridge, T.L.

    1989-10-01

    This document describes the Hanford Internal Dosimetry program. Program Services include administrating the bioassay monitoring program, evaluating and documenting assessments of internal exposure and dose, ensuring that analytical laboratories conform to requirements, selecting and applying appropriate models and procedures for evaluating internal radionuclide deposition and the resulting dose, and technically guiding and supporting Hanford contractors in matters regarding internal dosimetry. 13 refs., 16 figs., 42 tabs.

  10. Dosimetry of iodoantipyrine.

    Science.gov (United States)

    Chu, R Y; Ekeh, S; Basmadjian, G

    1989-01-01

    Dosimetry of iodoantipyrine labeled with radioactive iodine was determined by measuring the biodistribution of 131I-iodoantipyrine in 41 female rabbits. Following administration of the radiopharmaceutical, subjects were killed at 0.5, 6, 12, 17, 24, 36, and 48 h. Organs and samples of tissues and body fluids were assayed. Results were corrected for physical decay. Exponential functions were employed to describe the time-concentration curves; representative value would be the biological half life of 9.96 +/- 0.55 h for blood. Cumulated activity estimates for 123I, 125I and 131I were then computed. Extrapolation to absorbed dose in humans followed the formulation of the Medical International Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. The whole body absorbed doses are 7 mu Gray, 5 mu Gray and 29 mu Gray per MBq of 123I, 125I, and 131I administered respectively.

  11. Medical dosimetry in Hungary

    Science.gov (United States)

    Turák, O.; Osvay, M.; Ballay, L.

    2012-09-01

    Radiation exposure of medical staff during cardiological and radiological procedures was investigated. The exposure of medical staff is directly connected to patient exposure. The aim of this study was to determine the distribution of doses on uncovered part of body of medical staff using LiF thermoluminescent (TL) dosimeters in seven locations. Individual Kodak film dosimeters (as authorized dosimetry system) were used for the assessment of medical staff's effective dose. Results achieved on dose distribution measurements confirm that wearing only one film badge under the lead apron does not provide enough information on the personal dose. The value of estimated annual doses on eye lens and extremities (fingers) were in good correlation with international publications.

  12. Fundamentals of Radiation Dosimetry

    Science.gov (United States)

    Bos, Adrie J. J.

    2011-05-01

    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.

  13. Dosimetry considerations in phototherapy

    Energy Technology Data Exchange (ETDEWEB)

    Profio, A.E.; Doiron, D.R.

    Dosimetry in phototherapy involves a determination of the energy absorbed per unit mass of tissue, corrected for the quantum yield in a photochemical reaction. The dose rate in photochemotherapy of cancer with hematoporphyrin derivative and visible light is related to the extinction coefficient, quantum yield for singlet oxygen production, concentration of sensitizer and energy flux density at depth. Data or methods of determining these quantities are presented. Calculations have been performed for the energy flux density at depth, as a function of the total attenuation coefficient and ratio of scattering coefficient to total attenuation coefficient, for isotropic scattering in slab geometry. For small absorption, these depth dose curves exhibit a maximum within the tissue followed by an exponential decrease.

  14. Dosimetry considerations in phototherapy

    Energy Technology Data Exchange (ETDEWEB)

    Profio, A.E.; Doiron, D.R.

    1981-03-01

    Dosimetry in phototherapy involves a determination of the energy absorbed per unit mass of tissue, corrected for the quantum yield in a photochemical reaction. The dose rate in photochemotherapy of cancer with hematoporphyrin derivative and visible light is related to the extinction coefficient, quantum yield for singlet oxygen production, concentration of sensitizer and energy flux density at depth. Data or methods of determining these quantities are presented. Calculations have been performed for the energy flux density at depth, as a function of the total attenuation coefficient and ratio of scattering coefficient to total attenuation coefficient, for isotropic scattering in slab geometry. For small absorption, these depth dose curves exhibit a maximum within the tissue followed by an exponential decrease.

  15. Diagnose und Therapie der Depression bei Morbus Parkinson

    Directory of Open Access Journals (Sweden)

    Klein N

    2004-01-01

    Full Text Available Depressive Episoden sind die häufigsten psychiatrischen Komplikationen bei MP, erschweren oft wesentlich dessen Verlauf und setzen die Lebensqualität der Patienten weiter herab. Als mögliche Risikofaktoren für die Entstehung einer depressiven Symptomatik bei MP gelten: junges Lebensalter und jugendlicher Ausbruch des MP, weibliches Geschlecht, rechtsseitiger Hemiparkinsonismus, zunehmender Schweregrad der körperlichen Beeinträchtigung, Akinesie, Angst und psychotische Symptomatik. Durch die große Überschneidung von Symptomen des MP und der Depression kann es schwierig sein, die Diagnose "Depression bei MP" zu stellen. Der Neuropsychiater sollte diese Komplikation bei MP erwarten bzw. suchen. Pathophysiologisch korreliert die Depression bei Patienten mit MP sowohl mit dem Mangel an Dopamin als auch mit der Beeinträchtigung serotonerger und noradrenerger Neurotransmission. Eine nicht unwesentliche Ursache der Depression bei MP ist auch der Streß, den eine behindernde, chronische und unheilbare Erkrankung subjektiv im Patienten erzeugt. Obwohl die Depression einen entscheidenden Einfluß auf die Lebensqualität der Patienten und ihrer Angehörigen hat und der Behandlung daher ein wichtiger Stellenwert zukommt, wurden bis zum heutigen Tag nur unzureichende Untersuchungen zur Therapie der Depression bei MP durchgeführt. Für die Zukunft gilt es, anhand der Ergebnisse von randomisierten, doppelblinden Studien, Behandlungsalgorithmen für die Therapie der Depression bei Patienten mit MP zu entwickeln.

  16. Upgrading the dosimetry at Ontario Hydro

    Energy Technology Data Exchange (ETDEWEB)

    Hirning, C.R. [Ontario Hydro, Whitby, ON (Canada). Health Physics Dept.

    1996-12-01

    Ontario Hydro has embarked upon a major programme to replace and upgrade its external dosimetry systems. In two year`s time, the utility expects to have two state-of-the-art dosimetry systems in place: a new TLD dosimetry of legal record that was designed nearly 30 years ago; and an electronic dosimetry system which could eventually replace the TLD as the primary system. (Author).

  17. Characterising an aluminium oxide dosimetry system.

    Science.gov (United States)

    Conheady, Clement F; Gagliardi, Frank M; Ackerly, Trevor

    2015-09-01

    In vivo dosimetry is recommended as a defence-in-depth strategy in radiotherapy treatments and is currently employed by clinics around the world. The characteristics of a new optically stimulated luminescence dosimetry system were investigated for the purpose of replacing an aging thermoluminescence dosimetry system for in vivo dosimetry. The stability of the system was not sufficient to satisfy commissioning requirements and therefore it has not been released into clinical service at this time.

  18. MRI for myocarditis; MRT bei Myokarditis

    Energy Technology Data Exchange (ETDEWEB)

    Gutberlet, M.; Luecke, C.; Krieghoff, C.; Hildebrand, L.; Steiner, J.; Adam, J.; Grotthoff, M.; Lehmkuhl, L. [Herzzentrum, Universitaet Leipzig, Abteilung fuer Diagnostische und Interventionelle Radiologie, Leipzig (Germany); Lurz, P.; Eitel, I.; Thiele, H. [Herzzentrum, Universitaet Leipzig, Abteilung Kardiologie, Leipzig (Germany)

    2013-01-15

    Cardiovascular magnetic resonance imaging (CMRI) has become the primary tool for the non-invasive assessment in patients with suspected myocarditis, especially after exclusion of acute coronary syndrome (ACS) for the differential diagnosis. Various MRI parameters are available which have different accuracies. Volumetric and functional ventricular assessment and the occurrence of pericardial effusion alone demonstrate only a poor sensitivity and specificity. The calculation of the T2-ratio (edema assessment), the early or global relative myocardial enhancement (gRE) and the late gadolinium enhancement (LGE), which represents irreversibly injured myocardium, are more specific parameters. All MRI parameters demonstrate the best accuracy in infarct-like acute myocarditis, whereas in chronic myocarditis sensitivity and specificity are less accurate. Therefore, a multisequential (at least two out of three parameters are positive) approach is recommended. The assessment of the value of newer, more quantitative MRI sequences, such as T1 and T2-mapping is still under investigation. (orig.) [German] Die kardiale MRT stellt die primaere nichtinvasive bildgebende Modalitaet bei Verdacht auf Myokarditis dar, insbesondere auch nach Ausschluss eines akuten Koronarsyndroms (ACS) zur Differenzialdiagnose. Verschiedene MR-Parameter mit unterschiedlicher Wertigkeit stehen zur Verfuegung. Die Beurteilung der Volumetrie und Ventrikelfunktion weisen ebenso wie der Nachweis eines Perikardergusses alleine nur eine geringe Sensitivitaet und Spezifitaet auf. Die spezifischeren MRT-Inflammationsparameter stellen die T2-Ratio (Oedemnachweis), die fruehe Kontrastmittelanreicherung bzw. das globale relative Enhancement (gRE) und die spaete Kontrastmittelanreicherung, das so genannte Late-Gadolinium-Enhancement (LGE) als Zeichen eines irreversiblen Myokardschadens dar. Alle MR-Parameter zeigen die beste diagnostische Genauigkeit bei einer ''infarktaehnlichen'' akuten

  19. Neue Therapieoptionen bei Neuroendokrinen Tumoren des Gastrointestinaltraktes

    Directory of Open Access Journals (Sweden)

    Lipp RW

    2016-01-01

    Full Text Available Neuroendokrine Tumoren (NET des Gastrointestinaltraktes und des Pankreas (GEP-NET werden zu den seltenen Tumoren gezählt. Auch wenn die jährliche Inzidenz dieser Erkrankung gering erscheint, weist diese Tumorentität die zweithöchste Prävalenz des Gastrointestinaltraktes auf. In den letzten beiden Jahrzehnten bewährten sich Somatostatinanaloga zur Behandlung symptomatischer NET-Patienten mit niedrigen Proliferationsindex Ki67 ≤ 10 % und zeigten zuletzt auch einen antiproliferativen Effekt unabhängig von der Hormonsynthese. In den letzten Jahren konnte das antiproliferative Potential von Everolimus (Afinitor® – ein m-Tor-Inhibitor – und Suntinib (Sutent® – ein Multikinase-Inhibitor – in der Behandlung von symptomatischen und asymptomatischen pankreatischen NET-Patienten gezeigt werden.br Im letzten Jahr wurden zwei Phase-III-Studien veröffentlicht bzw. präsentiert. Die Radiant- 4-Studie zeigte eine Verbesserung des progressionsfreien Überlebens bei asymptomatischen Patienten mit NETs des Gastrointestinaltraktes, der Lunge und bei NET-Patien ten mit „cancer of unknown primary“ (CUP, mit radiologisch gesicherter Tumorprogression zum Studien eintritt. Die NETTER-1-Studie ist die erste randomisierte kontrollierte Multicenter-Studie, die den Effekt der Radioligandentherapie auf das progressionsfreie Überleben bei Patienten mit progredientem Dünndarm-NET untersucht. Diese Übersicht fasst nun die Ergebnisse beider Studien zusammen und gibt einen möglichen Ausblick für die tägliche Praxis.

  20. Nuclear accident dosimetry intercomparison studies.

    Science.gov (United States)

    Sims, C S

    1989-09-01

    Twenty-two nuclear accident dosimetry intercomparison studies utilizing the fast-pulse Health Physics Research Reactor at the Oak Ridge National Laboratory have been conducted since 1965. These studies have provided a total of 62 different organizations a forum for discussion of criticality accident dosimetry, an opportunity to test their neutron and gamma-ray dosimetry systems under a variety of simulated criticality accident conditions, and the experience of comparing results with reference dose values as well as with the measured results obtained by others making measurements under identical conditions. Sixty-nine nuclear accidents (27 with unmoderated neutron energy spectra and 42 with eight different shielded spectra) have been simulated in the studies. Neutron doses were in the 0.2-8.5 Gy range and gamma doses in the 0.1-2.0 Gy range. A total of 2,289 dose measurements (1,311 neutron, 978 gamma) were made during the intercomparisons. The primary methods of neutron dosimetry were activation foils, thermoluminescent dosimeters, and blood sodium activation. The main methods of gamma dose measurement were thermoluminescent dosimeters, radiophotoluminescent glass, and film. About 68% of the neutron measurements met the accuracy guidelines (+/- 25%) and about 52% of the gamma measurements met the accuracy criterion (+/- 20%) for accident dosimetry.

  1. Rezidivierende Endometriose bei Kinderwunsch: Operieren oder stimulieren?

    Directory of Open Access Journals (Sweden)

    Brunbauer M

    2012-01-01

    Full Text Available Kurzfassung: Endometriose ist neben dem Tubenverschluss und dem PCO-Syndrom eine der Hauptursachen für reduzierte Fertilität bei der Frau. Zur eindeutigen Diagnosesicherung ist die operative Diagnostik Standard. Eine Sanierung ist in vielen Fällen in der gleichen Sitzung möglich. Um nichts unnötig zu (zer- stören, sei die Maxime: eher weniger als mehr. Ein Rezidiv bedeutet eine weitere Reduktion der Schwangerschaftsrate. Eine Zweitoperation kann zwar Beschwerden lindern, verbessert aber die Spontan-Schwangerschaftsrate nur gering. Der Zweiteingriff ist also bezüglich der reinen Schwangerschaftsrate einer modernen IVF-Behandlung eindeutig unterlegen.

  2. Genetische Regulation der Oxacillinresistenz bei Staphylococcus epidermidis

    OpenAIRE

    Huck, Jörn Christian

    2015-01-01

    Für S. epidermidis hängt die Expression der Oxacillinresistenz wesentlich von der Aktivität des alternativen sigma-Faktors sB ab. Durch Ausschaltung des Anti-sigma Faktors rsbW lässt sich mit dieser Arbeit erstmalig eine homogene Expression der Oxacillin Resistenz herbeiführen. Somit wurde ein Gen für S. epidermidis identifiziert, welches bei Inaktivierung in der Lage ist, einen Wechsel von heterogener zu homogener Oxacillinresistenz zu verursachen. Außerdem konnte gezeigt werden, dass dieser...

  3. Dosimetry of iodoantipyrine

    Energy Technology Data Exchange (ETDEWEB)

    Chu, R.Y.L.; Ekeh, S. (Oklahoma Univ., Oklahoma City, OK (USA). Dept. of Radiological Sciences; Veterans Administration Medical Center, Oklahoma City, OK (USA)); Basmadjian, G. (Oklahoma Univ., Oklahoma City, OK (USA). Dept. of Pharmaceutical Sciences)

    1989-12-01

    Dosimetry of iodoantipyrine labeled with radioactive iodine was determined by measuring the biodistribution of {sup 131}I-iodoantipyrine in 41 female rabbits. Following administration of the radiopharmaceutical, subjects were killed at 0.5, 6, 12, 17, 24, 36, and 48 h. Organs and samples of tissues and body fluids were assayed. Results were corrected for physical decay. Exponential functions were employed to describe the time-concentration curves; representative value would be the biological half life of 9.96+-0.55 h for blood. Cumulated activity estimates for {sup 123}I, {sup 125}I and {sup 131}I were then computed. Extrapolation to absorbed dose in humans followed the formulation of the Medical International Radiation Dose (MIRD) Committee of the Society of Nuclear Medicine. The whole body absorbed doses are 0.7 {mu}Gray, 0.5 {mu}Gray and 2.9 {mu}Gray per MBq of {sup 123}I, {sup 123}I, and {sup 131}I administered respectively. (orig.).

  4. Information from the Dosimetry Service

    CERN Multimedia

    2006-01-01

    Please note the following opening hours of the Service: In June: Every morning from 8:30 to 12:00 In July: Mondays, Wednesdays and Fridays from 8:30 to 11:30 Closed all day on Tuesdays and Thursdays From 31st July onwards: Every morning from 8:30 to 12:00 The Service is closed in the afternoons. We should like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCTs) must always be returned to the Service after use and must not be left on the racks in the experimental areas or in the secretariats. Dosimetry Service Tel 72155 Bldg. 24 E 011 Dosimetry.service@cern.ch http://cern.ch/rp-dosimetry

  5. For information: Individual dosimetry service

    CERN Multimedia

    2004-01-01

    The service has noticed that there are dosimeter holders who have changed their activities and thus have no longer need of dosimeter as a permanent basis in their work (persons who go rarely to the controlled areas). The reduction of persons in the regular distribution list of dosimeters will lighten the work of the service (distribution, evaluation and consolidation of doses) as well as the work of the distributors, needless to say the economical input this would have for CERN. For the persons who only need a dosimeter temporarily we would like to remind that there is a quick and simple procedure to have one immediately from the Individual Dosimetry Service. Please contact the service (dosimetry.service@cern.ch) if you do not need a dosimeter regularly. Thank you for your cooperation. http://cern.ch/rp-dosimetry

  6. Information from the Dosimetry Service

    CERN Multimedia

    2006-01-01

    CERN Staff and Users can now consult their dose records for an individual or an organizational unit with HRT. Please see more information on our web page http://cern.ch/rp-dosimetry. The Dosimetry Service is open every morning from 8.30 - 12.00, and closed in the afternoons. We would like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCT's) must always be returned to the Service after use and must not be left on the racks in the experimental areas or in the secretariats.

  7. Information from the Dosimetry Service

    CERN Multimedia

    2006-01-01

    CERN Staff and Users can now consult their dose records for an individual or an organizational unit with HRT. Please see more information on our web page: http://cern.ch/rp-dosimetry. The Dosimetry Service is open every morning from 8.30 to 12.00 and is closed in the afternoons. We would like to remind you that dosimeters cannot be sent to customers by internal mail. Short-term dosimeters (VCT's) must always be returned to the Service after use and must not be left on the racks in the experimental areas or in the secretariats.

  8. Antikoagulation bei Vorhofflimmern: Wie und mit welchem Medikament?

    Directory of Open Access Journals (Sweden)

    Gary T

    2015-01-01

    Full Text Available Direkte orale Antikoagulantien (DOAKs sind Alternativen zu Vitamin-K-Antagonisten (VKA bei Vorhofflimmerarrhythmie- (VHFA- Patienten und werden diese in dieser Indikation zu weiten Teilen ersetzen. Bei VHFA-Patienten mit Dialyse oder mechanischen Herzklappen sind VKA nach wie vor die einzige Option. Bei der Gabe von DOAKs sollte vor Therapieeinleitung auf das Vorhandensein von Begleiterkrankungen (z. B. Niereninsuffizienz, stattgehabte gastrointestinale Blutungen etc. sowie auf die Begleittherapie der Patienten (z. B. Amiodaron etc. geachtet werden, um die passende Substanz in der richtigen Dosierung zu wählen.

  9. Wirksamkeit von Aromatherapie bei postoperativer Nausea und Vomiting bei Erwachsenen: Systematische Literaturreview

    OpenAIRE

    Schnyder, Samira; Z‘Brun Schnyder, Silvia

    2015-01-01

    Problembeschreibung: Postoperative Nausea und Vomiting (PONV) stellt neben Schmerz eine der häufigsten postoperativen Komplikationen dar. Die Inzidenz beträgt bei gynäkologischen Patientinnen 80%. Symptome und Folgen von PONV können physische, psychische, emotionale und finanzielle Auswirkungen für die Patienten und das Personal haben. Postoperative Nausea und Vomiting wird meistens medikamentös mit Antiemetika behandelt. Diese Medikamente können jedoch viele Nebenwirkungen aufweisen. D...

  10. Dosimetry for Electron Beam Applications

    DEFF Research Database (Denmark)

    Miller, Arne

    1983-01-01

    This report describes two aspects of electron bean dosimetry, on one hand developaent of thin fil« dosimeters and measurements of their properties, and on the other hand developaent of calorimeters for calibration of routine dosimeters, e.g. thin films. Two types of radiochromic thin film...

  11. In aqua vivo EPID dosimetry

    NARCIS (Netherlands)

    Wendling, M.; McDermott, L.N.; Mans, A.; Olaciregui-Ruiz, I.; Pecharroman-Gallego, R.; Sonke, J.J.; Stroom, J.; Herk, M. van; Mijnheer, B.J.

    2012-01-01

    PURPOSE: At the Netherlands Cancer Institute--Antoni van Leeuwenhoek Hospital in vivo dosimetry using an electronic portal imaging device (EPID) has been implemented for almost all high-energy photon treatments of cancer with curative intent. Lung cancer treatments were initially excluded, because t

  12. In vivo dosimetry in brachytherapy

    DEFF Research Database (Denmark)

    Tanderup, Kari; Beddar, Sam; Andersen, Claus Erik;

    2013-01-01

    In vivo dosimetry (IVD) has been used in brachytherapy (BT) for decades with a number of different detectors and measurement technologies. However, IVD in BT has been subject to certain difficulties and complexities, in particular due to challenges of the high-gradient BT dose distribution and th...

  13. Portal dosimetry in wedged beams

    NARCIS (Netherlands)

    Spreeuw, H.; Rozendaal, R.; Camargo, P.; Mans, A.; Wendling, M.; Olaciregui-Ruiz, I.; Sonke, J.J.; Herk, M. van; Mijnheer, B.

    2015-01-01

    Portal dosimetry using electronic portal imaging devices (EPIDs) is often applied to verify high-energy photon beam treatments. Due to the change in photon energy spectrum, the resulting dose values are, however, not very accurate in the case of wedged beams if the pixel-to-dose conversion for the s

  14. Finding out synergy effects in the combination of composting and fermentation methods to recycle biological wastes, taking into consideration the local infrastructures; Ermittlung von Synergieeffekten bei der Kombination von Kompostierungs- und Vergaerungsverfahren zur Verwertung von Bioabfaellen unter Beruecksichtigung der lokalen Infrastruktur

    Energy Technology Data Exchange (ETDEWEB)

    Krumm, W.; Schoenenberg, T.

    2001-12-01

    In a combined composting and fermentation unit, a large number of components of mechanical, biological and thermal technical procedures are connected with each other. Due to the high degree of complexity, empirical methods are not suitable for the theoretical investigation of a whole system at a location. Therefore, it is more difficult to deal with environmental questions in a scientific way. The project of this research project is to quantify energy and cost-relevant synergy effects for different system configurations dependent on variable frame conditions. The coherences are described using the method of mathematical modelling and simulation. A combined composting and fermentation unit is discussed as an example. [German] Bei einer kombinierten Kompostierungs- und Vergaerungsanlage sind eine grosse Anzahl von Komponenten der mechanischen, biologischen und thermischen Verfahrenstechnik miteinander verknuepft. Wegen der hohen Komplexitaet sind empirische Methoden fuer die theoretische Untersuchung eines gesamten Anlagenstandortes ungeeignet. Die wissenschaftliche Bearbeitung umweltrelevanter Fragestellungen wird deshalb erschwert. Das Ziel dieses Forschungsprojekts ist die Quantifizierung umwelt- und kostenrelevanter Synergieeffekte fuer unterschiedliche Systemkonfigurationen in Abhaengigkeit von veraenderlichen Randbedingungen. Die Zusammenhaenge werden mit Hilfe der Methode der mathematischen Modellbildung und Simulation beschrieben. Es wird beispielhaft ein kombiniertes Kompostierungs- und Vergaerungsverfahren betrachtet. (orig.)

  15. Plutonium worker dosimetry.

    Science.gov (United States)

    Birchall, Alan; Puncher, M; Harrison, J; Riddell, A; Bailey, M R; Khokryakov, V; Romanov, S

    2010-05-01

    Epidemiological studies of the relationship between risk and internal exposure to plutonium are clearly reliant on the dose estimates used. The International Commission on Radiological Protection (ICRP) is currently reviewing the latest scientific information available on biokinetic models and dosimetry, and it is likely that a number of changes to the existing models will be recommended. The effect of certain changes, particularly to the ICRP model of the respiratory tract, has been investigated for inhaled forms of (239)Pu and uncertainties have also been assessed. Notable effects of possible changes to respiratory tract model assumptions are (1) a reduction in the absorbed dose to target cells in the airways, if changes under consideration are made to the slow clearing fraction and (2) a doubling of absorbed dose to the alveolar region for insoluble forms, if evidence of longer retention times is taken into account. An important factor influencing doses for moderately soluble forms of (239)Pu is the extent of binding of dissolved plutonium to lung tissues and assumptions regarding the extent of binding in the airways. Uncertainty analyses have been performed with prior distributions chosen for application in epidemiological studies. The resulting distributions for dose per unit intake were lognormal with geometric standard deviations of 2.3 and 2.6 for nitrates and oxides, respectively. The wide ranges were due largely to consideration of results for a range of experimental data for the solubility of different forms of nitrate and oxides. The medians of these distributions were a factor of three times higher than calculated using current default ICRP parameter values. For nitrates, this was due to the assumption of a bound fraction, and for oxides due mainly to the assumption of slower alveolar clearance. This study highlights areas where more research is needed to reduce biokinetic uncertainties, including more accurate determination of particle transport rates

  16. ESR dosimetry: achievements and challenges

    Energy Technology Data Exchange (ETDEWEB)

    Baffa, O., E-mail: baffa@usp.br [Universidade de Sao Paulo, Departamento de Fisica, Av. Bandeirantes 3900, 14040-901 Ribeirao Preto, Sao Paulo (Brazil)

    2015-10-15

    Full text: Electron Spin Resonance (ESR), also known as Electron Paramagnetic Resonance (EPR) and more recently as Electron Magnetic Resonance (Emr), is a spectroscopy technique able to detect unpaired electrons such as those created by the interaction ionizing radiation with matter. When the unpaired electrons created by ionizing radiation are stable over some reasonable time, ESR can be used to measure the radiation dose deposited in the material under study. In principle, any insulating material that satisfies this requisite can be used as a dosimeter. ESR has been used in retrospective dosimetry in case of radiological accidents using natural constituents of human body such as teeth, bones and nails as well as fortuitous materials as sugar, sweeteners and plastics. When using teeth the typical detected dose is 0.5 Gy for, for X-Band spectrometers (9 GHz) and even lower doses if higher frequency spectrometers are used. Clinical dosimetry is another area of potential use of this dosimetric modality. In this application the amino acid alanine has been proposed and being used. Alanine dosimeters are very easy to prepare and require no complicated treatments for use. Alanine/ESR dosimetry satisfies many of the required properties for clinical applications such as water equivalent composition, independence of response for the energy range used in therapy and high precision. Other organic materials such as ammonium tartrate are being investigated to increase the sensitivity of ESR for clinical applications. Finally, industrial applications can also benefit from this dosimetry. The challenges to expand applications, the number of users and research groups of ESR dosimetry will be discussed. (Author)

  17. Suspension membrane reactor for biological elimination of non-degradable materials from mixed effluents. Final report; Suspensionsmembranreaktor zur biologischen Eliminierung schwer abbaubarer Stoffe aus Abwassergemischen. Abschlussbericht

    Energy Technology Data Exchange (ETDEWEB)

    Raebiger, N.; Schierenbeck, A.

    2002-07-01

    An earlier research project had shown that a combined process involving membrane filtration and a bioreactor ensure substrate-specific times of residue inside the reactor, i.e. high selective conversation at low discharge rates. The second project aimed at higher flexibility. For this purpose, a two-stage suspension membrane reactor was developed in which the filtration stage and the bioreactor were decoupled. The liquid effluents are concentrated first in a nanofiltration stage, and the permeate, which should be free of non-degradable materials, is discharged. The concentrate is treated in the biological reaction stage and recirculated into the nanofiltration stage in order to ensure complete degradation during a substrate-specific time of residue. An intermediate microfiltration stage serves to retain biomass and prevent the growth of a biofilm in the nanofiltration stage. The method was tested with the practically relevant model pollutant 4-chlorophenol and a real industrial effluent from the antifelting stage of a Bremen woollen mill (Bremer Wollkaemmerei), with a high AOX concentration. [German] Im vorhergehenden Teil des Forschungsvorhabens konnte gezeigt werden, dass durch eine kombinierte Anwendung der Membranfiltration mit einem Bioreaktor eine substratspezifische Verweilzeitverteilung im Reaktor und damit eine hohe selektive Umsatzleistung bei gleichzeitig niedrigen Ablaufwerten realisierbar ist. Um eine groessere Flexibilitaet bei dem Einsatz verschiedener Membranmodule zu realisieren, wurde in dem zweiten Abschnitt des Forschungsvorhabens eine zweistufige Anlage vom Typ des Suspensions-Membranreaktors entwickelt, bei der Filtration und Bioreaktor entkoppelt werden. Das zu reinigende Abwasser wird zunaechst in einer Nanofiltrationsstufe aufkonzentriert, das moeglichst an schwer abbaubaren Stoffen freie Permeat bildet den Ablauf der Anlage. Der Konzentratstrom wird in der nachfolgenden Reaktionsstufe biologisch behandelt und in die Nanofiltrationsstufe

  18. SPECT in epilepsies; SPECT bei Epilepsien

    Energy Technology Data Exchange (ETDEWEB)

    Stefan, H. [Neurologische Klinik, Univ. Erlangen-Nuernberg, Zentrum Epilepsie Erlangen (Germany)

    1997-06-01

    Registration of regional cerebral blood flow provides important new data for the investigation of pathophysiological processes in epilepsies. Further to the registration of perfusions, receptor studies are employed for the differentiation of localisation in focal epilepsies. For ultimative issues interictal registrations are supplemented by ictal recordings during the epileptic seizure. The combination of SPECT and electrophysiological registration can contribute to analysis of propagation of focal epileptic activity. (orig.) [Deutsch] Die Messung der regionalen Hirndurchblutung liefert wichtige neue Erkenntnis zur Untersuchung pathophysiologischer Ablaeufe bei Epilepsien. Ergaenzend zur Registrierung der Perfusion koennen Rezeptor-Studien zur Differenzierung der Lokalisation fokaler Epilepsien beitragen. Interiktale Registrierungen werden fuer letztere Fragestellung durch iktuale Messungen waehrend des epileptischen Anfalls ergaenzt. Die Kombination von SPECT und elektrophysiologischen Registrierungen kann zur Analyse der Propagation fokaler epileptischer Aktivitaet beitragen. (orig.)

  19. Neue orale immunmodulierende Therapien bei Multipler Sklerose

    Directory of Open Access Journals (Sweden)

    Berger T

    2014-01-01

    Full Text Available Seit 20 Jahren sind nun krankheitsmodifizierende Therapien zur Behandlung von Patienten mit insbesondere schubförmiger Multipler Sklerose (MS verfügbar. Ungeachtet der therapeutischen Errungenschaften der aktuellen Basis- und Eskalationstherapien bestehen Limitationen hinsichtlich Nutzen einerseits und Risiken andererseits. Die Konsequenz daraus, gemeinsam mit neuen Konzepten zur Immunopathogenese von MS, ist die Weiterentwicklung neuer und innovativer MS-Therapien. Die vorliegende Übersicht beschreibt im Detail 3 neue orale Immunmodulatoren zur Behandlung der schubförmigen MS. Darüber hinaus werden die Ergebnisse und die erfolgte/anstehende/eingereichte EU-Marktzulassung dieser 3 Therapien in den Kontext der Erwartungshaltungen an neue immunmodulierende Therapien bei MS gesetzt.

  20. Pathomechanismen der Atherosklerose bei Diabetes mellitus

    Directory of Open Access Journals (Sweden)

    Mulac K

    2005-01-01

    Full Text Available Die epidemiologischen Daten weisen darauf hin, daß die Prävalenz des Diabetes mellitus in den nächsten Jahrzehnten ansteigen wird, und damit im Zusammenhang auch die vaskulären Komplikationen zunehmen werden. Die akzelerierte Atherosklerose bei Diabetikern ist durch die über weite Strecken des Tages vorliegende Hyperglykämie, die Dyslipidämie, das Auftreten von erhöhten Werten von asymmetrischem Dimethylarginin und "advanced glycation end products" mitbestimmt. All diese Mechanismen induzieren die Bildung und Freisetzung von Zytokinen, Chemokinen, Adhäsionsmolekülen, freien Sauerstoffradikalen und aktivierten Gerinnungsfaktoren, die über die zu Beginn vorliegende endotheliale Dysfunktion in eine akzelerierte und progrediente Atherosklerose mit allen vaskulären Problemen münden.

  1. Imaging of hip arthroplasty; Bildgebung bei Hueftprothesen

    Energy Technology Data Exchange (ETDEWEB)

    Breitenseher, M.J. [Abteilung fuer Osteologie, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Klinische Abteilung fuer Radiodiagnostik chirurgischer Faecher, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Ludwig-Boltzmann-Institut fuer Radiologische Tumordiagnostik, Wien (Austria); Mayerhoefer, M. [Klinische Abteilung fuer Radiodiagnostik chirurgischer Faecher, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Gottsauner-Wolf, F. [Universitaetsklinik fuer Orthopaedie, Wien (Austria); Abteilung fuer Orthopaedie, Allgemeines oeffentliches KH, Krems (Austria); Krestan, C.; Imhof, H. [Abteilung fuer Osteologie, Universitaetsklinik fuer Radiodiagnostik, Wien (Austria); Toma, C.D. [Universitaetsklinik fuer Orthopaedie, Wien (Austria)

    2002-06-01

    Hip arthroplasty has become a common and still increasing procedure for the treatment of osteoarthritis, advanced head necrosis, post-inflammatory arthritis or rheumatoid arthritis.Radiography is the most important imaging modality for monitoring the normal, asymptomatic hip arthroplasty. Radiographs are obtained at the end of a surgical treatment, to exclude complications like fracture or component misplacement. In the follow-up radiographs are used for the diagnosis of loosening and infection of the hip arthroplasty as well as soft tissue ossification. Together with the history and clinical information, the analysis of morphological findings allows to find the grade of loosening. MRI has been advocated in the diagnosis of infection, in particular in the localisation of soft tissue involvement.Imaging, especially by radiographs, is used for the evaluation of the normal and complicated follow-up of hip arthroplasty. (orig.) [German] Die Implantation einer Hueftgelenkprothese ist eine immer haeufiger verwendete medizinische Massnahme bei Erkrankungen des Hueftgelenks wie Koxarthrose, Hueftkopfnekrose, postentzuendliche Arthrose oder rheumatoide Arthritis.Von den bildgebenden Methoden ist das konventionelle Roentgen die wichtigste Untersuchung, um den normalen Behandlungsverlauf einer Hueftprothese zu monitieren. Das Roentgen kann fruehzeitige Komplikationen wie Fraktur oder Fehlposition intraoperativ oder eine Luxation postoperativ erfassen. Im laengerfristigen Verlauf ist das Roentgen zur Diagnose von Infektion, Prothesenlockerung und Weichteilverknoecherung geeignet. In Zusammenschau mit der Klinik ermoeglicht die Analyse morphologisch-radiologischer Details, die Wahrscheinlichkeit einer Lockerung abzuschaetzen. Bei Protheseninfektionen ermoeglicht die MRT die Lokalisation von Weichteilentzuendungen.Die Methoden der Bildgebung, besonders das Roentgen, haben in der Beurteilung des normalen und in der Diagnose des komplizierten Verlaufes einen hohen Stellenwert

  2. Das Verhalten von Mastputen bei unterschiedlicher Besatzdichte und Einstreuart

    OpenAIRE

    Günthner, Pia

    2013-01-01

    Die Europäische Union bereitet eine Haltungsverordnung für Puten vor, die in Deutschland die freiwillige Vereinbarung ersetzen soll. Die vorliegende Untersuchung soll wissenschaftliche Grundlagen zum Verhalten der Puten bei unterschiedlichen Besatzdichten liefern, um somit die bevorstehende Revision der Vereinbarung zu unterstützen. In der vorliegenden Arbeit wurden in 2 Mast-Durchgängen (Winter und Sommer) das Verhalten von Puten der Linie B.U.T. Big 6 bei unterschiedlichen Besatzdichten und...

  3. Physostigmin und postoperatives Delir bei Vorschulkindern: eine randomisierte Doppelblindstudie

    OpenAIRE

    Häusler, Julia Maria

    2013-01-01

    Einleitung Ein Teil der Vorschulkinder erwacht nach Narkosen verzögert, schwer agitiert und desorientiert. Bei ähnlichen Zuständen Erwachsener wird Physostigmin unter der Annahme, dass es sich bei diesem postoperativen Delir meist um ein „zentrales anticholinerges Syndrom“ handelt, erfolgreich eingesetzt. Die vorgestellte Studie soll diesen Ansatz auch für Kleinkinder überprüfen. Materialien und Methoden Insgesamt wurden 211 Kinder nach standardisierter Narkose in drei Prüfzentren re...

  4. Osteoporose bei Spondylitis ankylosans - Einfluß von Lebensgewohnheiten

    Directory of Open Access Journals (Sweden)

    Aglas F

    2004-01-01

    Full Text Available Krankheitsbedingte Artefakte können bei der SpA (Spondylitis ankylosans; Mb. Bechterew die Sensitivität einer Knochendichtemessung im Lumbalbereich beeinträchtigen. Das bei dieser rheumatischen Erkrankung bekannte Osteoporoserisiko ist neben genetischen Faktoren und Entzündungsmechanismen auch von verschiedenen exogenen Einflüssen abhängig. An 47 SpA-Patienten wurde mittels DEXA eine vergleichende Knochendichtemessung (BMD an der Hüfte (Schenkelhals und Ward'sches Dreieck sowie im Bereich der Wirbelsäule (L1-L4 vorgenommen. Zusätzlich erfolgte eine Erhebung der Lebens-Ernährungsgewohnheiten der SpA-Patienten in bezug auf die BMD, um exogene Einflüsse erfassen zu können. Die Knochendichtemessungen ergaben an der LWS wesentlich häufiger eine BMD im Normbereich als am proximalen Femur. Besonders deutliche Unterschiede traten im höheren Lebensalter auf, bei dem aufgrund von Kalzifizierungsvorgängen und Syndesmophyten an der LWS fälschlicherweise eine Dichtezunahme vorgetäuscht wird. Es kann daher bei SpA empfohlen werden, die wesentlich sensitivere Dichtemessung am Schenkelhals durchzuführen. Die über einen Zeitraum von 3 Jahren beobachteten, signifikant erhöhten, medianen CRP-Spiegel zeigen, daß eine permanente Aktivierung von Entzündungsprozessen bei SpA auch einen negativen Faktor betreffend des Knochenmasseverlustes darstellt. Die Analyse der Lebensgewohnheiten ergab, daß SpA-Patienten mit normaler BMD ausnahmslos regelmäßig kalziumreiche Nahrungsmittel zu sich nehmen; bei verminderter BMD wurde in der Mehrheit ein fehlender Konsum an Milchprodukten beobachtet. Leider war auch mit abnehmender BMD eine Verminderung der bei SpA empfohlenen Bewegungsübungen festzustellen. Aufgrund der Resultate ergibt sich eine generelle Empfehlung zu regelmäßigen Bewegungsübungen plus Osteoporosediät bei allen Bechterew-Patienten.

  5. Overcoming the Challenges of BeiDou Receiver Implementation

    Directory of Open Access Journals (Sweden)

    Mohammad Zahidul H. Bhuiyan

    2014-11-01

    Full Text Available Global Navigation Satellite System (GNSS-based positioning is experiencing rapid changes. The existing GPS and the GLONASS systems are being modernized to better serve the current challenging applications under harsh signal conditions. These modernizations include increasing the number of transmission frequencies and changes to the signal components. In addition, the Chinese BeiDou Navigation Satellite system (BDS and the European Galileo are currently under development for global operation. Therefore, in view of these new upcoming systems the research and development of GNSS receivers has been experiencing a new upsurge. In this article, the authors discuss the main functionalities of a GNSS receiver in view of BDS. While describing the main functionalities of a software-defined BeiDou receiver, the authors also highlight the similarities and differences between the signal characteristics of the BeiDou B1 open service signal and the legacy GPS L1 C/A signal, as in general they both exhibit similar characteristics. In addition, the authors implement a novel acquisition technique for long coherent integration in the presence of NH code modulation in BeiDou D1 signal. Furthermore, a simple phase-preserved coherent integration based acquisition scheme is implemented for BeiDou GEO satellite acquisition. Apart from the above BeiDou-specific implementations, a novel Carrier-to-Noise-density ratio estimation technique is also implemented in the software receiver, which does not necessarily require bit synchronization prior to estimation. Finally, the authors present a BeiDou-only position fix with the implemented software-defined BeiDou receiver considering all three satellite constellations from BDS. In addition, a true multi-GNSS position fix with GPS and BDS systems is also presented while comparing their performances for a static stand-alone code phase-based positioning.

  6. Overcoming the challenges of BeiDou receiver implementation.

    Science.gov (United States)

    Bhuiyan, Mohammad Zahidul H; Söderholm, Stefan; Thombre, Sarang; Ruotsalainen, Laura; Kuusniemi, Heidi

    2014-11-21

    Global Navigation Satellite System (GNSS)-based positioning is experiencing rapid changes. The existing GPS and the GLONASS systems are being modernized to better serve the current challenging applications under harsh signal conditions. These modernizations include increasing the number of transmission frequencies and changes to the signal components. In addition, the Chinese BeiDou Navigation Satellite system (BDS) and the European Galileo are currently under development for global operation. Therefore, in view of these new upcoming systems the research and development of GNSS receivers has been experiencing a new upsurge. In this article, the authors discuss the main functionalities of a GNSS receiver in view of BDS. While describing the main functionalities of a software-defined BeiDou receiver, the authors also highlight the similarities and differences between the signal characteristics of the BeiDou B1 open service signal and the legacy GPS L1 C/A signal, as in general they both exhibit similar characteristics. In addition, the authors implement a novel acquisition technique for long coherent integration in the presence of NH code modulation in BeiDou D1 signal. Furthermore, a simple phase-preserved coherent integration based acquisition scheme is implemented for BeiDou GEO satellite acquisition. Apart from the above BeiDou-specific implementations, a novel Carrier-to-Noise-density ratio estimation technique is also implemented in the software receiver, which does not necessarily require bit synchronization prior to estimation. Finally, the authors present a BeiDou-only position fix with the implemented software-defined BeiDou receiver considering all three satellite constellations from BDS. In addition, a true multi-GNSS position fix with GPS and BDS systems is also presented while comparing their performances for a static stand-alone code phase-based positioning.

  7. Results from 2010 Caliban Criticality Dosimetry Intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    Veinot, K. G.

    2011-10-12

    The external dosimetry program participated in a criticality dosimetry intercomparison conducted at the Caliban facility in Valduc, France in 2010. Representatives from the dosimetry and instrumentation groups were present during testing which included irradiations of whole-body beta/gamma (HBGT) and neutron thermoluminescent dosimeters (TLDs), a fixed nuclear accident dosimeter (FNAD), electronic alarming dosimeters, and a humanoid phantom filled with reference man concentrations of sodium. This report reviews the testing procedures, preparations, irradiations, and presents results of the tests.

  8. MISTI Shielding and Dosimetry Experiment Project

    Data.gov (United States)

    National Aeronautics and Space Administration — Reliable on-orbit dosimetry is necessary for understanding effects of space radiation environments on spacecraft microelectronics performance and comparison of...

  9. Fifth personnel dosimetry intercomparison study

    Energy Technology Data Exchange (ETDEWEB)

    Sims, C.S.

    1980-02-01

    The fifth Personnel Dosimetry Intercomparison Study (PDIS) was conducted at the Oak Ridge National Laboratory's (ORNL) Dosimetry Applications Research (DOSAR) facility on March 20-22, 1979. This study is the latest PDIS in the continuing series started at the DOSAR facility in 1974. The PDIS is a three day study, typically in March, where personnel dosimeters are mailed to the DOSAR facility, exposed to a range of low-level neutron radiation doses (1 to 15 mSv or equivalently, 100 to 1500 mrem) and neutron-to-gamma ratios (1:1-10:1) using the Health Physics Research Reactor (HPRR) as the radiation source, and returned to the participants for evaluation. This report is a summary and analysis of the results reported by the various participants. The participants are able to intercompare their results with those of others who made dose measurements under identical experimental conditions.

  10. Gel dosimetry for conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G. [Department of Physics of the University and INFN, Milan (Italy)]. e-mail: grazia.gambarini@mi.infn.it

    2005-07-01

    With the continuum development of conformal radio therapies, aimed at delivering high dose to tumor tissue and low dose to the healthy tissue around, the necessities has appeared of suitable improvement of dosimetry techniques giving the possibility of obtaining dose images to be compared with diagnostic images. Also if wide software has been developed for calculating dose distributions in the fields of various radiotherapy units, experimental verifications are necessary, in particular in the case of complex geometries in conformal radiotherapy. Gel dosimetry is a promising method for imaging the absorbed dose in tissue-equivalent phantoms, with the possibility of 3D reconstruction of the spatial dose distribution, with milli metric resolution. Optical imaging of gel dosimeters, based on visible light absorbance analysis, has shown to be a reliable technique for achieving dose distributions. (Author)

  11. NOTE FROM THE DOSIMETRY SERVICE

    CERN Multimedia

    2002-01-01

    During March, the Dosimetry Service will be opened from 8h30 to 12h in the morning and closed every afternoon.   We have established that many people, who are provided regularly with a personal dosimeter (film badge), have changed their activity and do not need it anymore, because they do not, or only exceptionally, enter controlled areas. If you are one of these persons, please contact the Personal Dosimeter Service (tel: 72155). There is a simplified procedure for obtaining a dosimeter if you have an immediate need for short-term visits in controlled areas. A reduction of the number of persons on the regular distribution list of dosimeters would decrease our and the distributors workload. It would also contribute to significant savings in the dosimetry, and thus CERN, budget. We thank you in advance for your understanding and for your collaboration.

  12. Über die Bedeutung von Magnesium bei der Tumorgenese

    Directory of Open Access Journals (Sweden)

    Golf SW

    2001-01-01

    Full Text Available Magnesium (Mg und die Tumorgenese sind in funktioneller wie in struktureller Hinsicht vielseitig miteinander verknüpft. Die Tumorzelle ist befähigt, Mg zu Lasten der Mg-Pools des Organismus in überhöhter Konzentration zu speichern, auch wenn für den Organismus eine negative Mg-Bilanz vorliegt. Durch diese Veränderung der Mg-Verteilung wird die Zelle in die Lage versetzt, den erhöhten Enegiebedarf bei Zellwachstum, z.B. durch eine induzierte Proteinbiosynthese und RNA-/DNA-Biosynthese, sowie gesteigerte Transportvorgänge zu decken. Andererseits verlaufen zahlreiche Vorgänge bei der Protein-, RNA-/DNA-Synthese, bei der Signalentstehung und -Propagation, bei Teilen der Mitose (Umbau der nukleären Struktur, Meta- und Anaphase sowie bei der Metastase in einem akzelerierten Modus kalziumabhängig, was diese Reaktionen stark Mg-abhängig gestaltet. Ca verbleibt nur wenige Sekunden funktional und wird durch Influx in das endoplasmatische Retikulum (ER aus dem Zytosol eliminiert, wodurch die Prozesse gebremst oder sogar unterbrochen werden. Für den Rücktransport von Ca in die intrazellulären Speicher wird Mg benötigt; somit kann Mg auch als Inhibitor dieser Vorgänge betrachtet werden. Auch die biologische Zytostase z. B. durch alpha-Tumornekrosefaktor (alphaTNF verläuft Mg-abhängig, da eine gesteigerte Resistenz der Tumorzelle gegenüber alphaTNF bei Mg-Mangel besteht. In struktureller Hinsicht kommen Mg bedeutende Wirkungen bei der Tumorgenese zu. Klassisch sind die schützenden Effekte von Mg bei der durch kanzerogene Metalle, z.B. Arsen, Beryllium, Chrom, Blei, Quecksilber und Nickel, ausgelösten Tumorgenese. Eine Schutzwirkung tritt vor allem bei einem Ungleichgewicht zwischen dem kanzerogenen Metall und dem Mg-Status des Organismus ein. In analoger Weise sind auch die Stabilität von DNA und RNA sowie Reparaturmechanismen von DNA-Schäden nur in ausreichender Gegenwart von funktionellem Mg optimiert. Hinsichtlich der Immunkompetenz

  13. Dosimetry for the external radiation therapy. Dosimetry with alanine; Dosimetrie fuer die externe Strahlentherapie. Dosimetrie mit Alanin

    Energy Technology Data Exchange (ETDEWEB)

    Anton, Mathias [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Arbeitsgruppe ' Alanin-Dosimetrie'

    2013-06-15

    The alanine-ESR dosimetry in the PTB is described. The response power of alanine related to the water energy dose for X-rays with average energy of 10-1000 keV is presented. Furthermore the application of alanine for the quality assurance in the radiation therapy is described by means of the prostate irradiation and the therapy of a tumor in the neck region as examples. (HSI)

  14. EPR Dosimetry - Present and Future

    Energy Technology Data Exchange (ETDEWEB)

    Regulla, D.F. [GSF - National Research Centre for Environment and Health, Institute of Radiation Protection, 85764 Neuherberg (Germany)

    1999-07-01

    In the past, IAEA has played a central role in stipulating research and development in EPR high-dose standardisation as well as in coordinating and organising international dose intercomparison programs, within the Member States of the United Nations from the mid-seventies till today. The future tasks of EPR dosimetry seem to tend towards different subjects such as bio markers, biological radiation effects, post-accident dose reconstruction in the environment, and retrospective human dosimetry. The latter may be considered a promising tool for epidemiology on the way to re-define radiation risk of man for chronicle radiation exposures, based on e.g. South Ural civil population and radiation workers. There are on-going international activities in the field of standardising high-level dosimetry by the American Standards on Testing and Materials (Astm), and by the International Organisation of Standards (ISO). The International Commission on Radiation Units and Measurements (ICRU) is considering the establishment of relevant recommendations concerning industrial radiation processing, but also human dose reconstruction. (Author)

  15. I-124 Imaging and Dosimetry

    Directory of Open Access Journals (Sweden)

    Russ Kuker

    2017-02-01

    Full Text Available Although radioactive iodine imaging and therapy are one of the earliest applications of theranostics, there still remain a number of unresolved clinical questions as to the optimization of diagnostic techniques and dosimetry protocols. I-124 as a positron emission tomography (PET radiotracer has the potential to improve the current clinical practice in the diagnosis and treatment of differentiated thyroid cancer. The higher sensitivity and spatial resolution of PET/computed tomography (CT compared to standard gamma scintigraphy can aid in the detection of recurrent or metastatic disease and provide more accurate measurements of metabolic tumor volumes. However the complex decay schema of I-124 poses challenges to quantitative PET imaging. More prospective studies are needed to define optimal dosimetry protocols and to improve patient-specific treatment planning strategies, taking into account not only the absorbed dose to tumors but also methods to avoid toxicity to normal organs. A historical perspective of I-124 imaging and dosimetry as well as future concepts are discussed.

  16. Dosimetry studies in Zaborie village.

    Science.gov (United States)

    Takada, J; Hoshi, M; Endo, S; Stepanenko, V F; Kondrashov, A E; Petin, D; Skvortsov, V; Ivannikov, A; Tikounov, D; Gavrilin, Y; Snykov, V P

    2000-05-01

    Dosimetry studies in Zaborie, a territory in Russia highly contaminated by the Chernobyl accident, were carried out in July, 1997. Studies on dosimetry for people are important not only for epidemiology but also for recovery of local social activity. The local contamination of the soil was measured to be 1.5-6.3 MBq/m2 of Cs-137 with 0.7-4 microSv/h of dose rate. A case study for a villager presently 40 years old indicates estimations of 72 and 269 mSv as the expected internal and external doses during 50 years starting in 1997 based on data of a whole-body measurement of Cs-137 and environmental dose rates. Mean values of accumulated external and internal doses for the period from the year 1986 till 1996 are also estimated to be 130 mSv and 16 mSv for Zaborie. The estimation of the 1986-1996 accumulated dose on the basis of large scale ESR teeth enamel dosimetry provides for this village, the value of 180 mSv. For a short term visitor from Japan to this area, external and internal dose are estimated to be 0.13 mSv/9d (during visit in 1997) and 0.024 mSv/50y (during 50 years starting from 1997), respectively.

  17. Einsparungspotential bei Antihypertensiva durch integriertes, ambulantes Hypertonikertraining

    Directory of Open Access Journals (Sweden)

    Kurz RW

    2001-01-01

    Full Text Available Die arterielle Hypertonie stellt unverändert einen der wichtigsten Risikofaktoren für Herzkreislauferkrankungen dar. Aufgrund der hohen Prävalenz und der zumeist lebenslangen Therapieindikation verursacht die antihypertensive Behandlung hohe Kosten für das Gesundheitswesen. Für verschiedene nicht-pharmakologische Maßnahmen konnte ein blutdrucksenkender Effekt nachgewiesen werden. In einem Versuch, einige dieser Therapiemodalitäten zu kombinieren, wurde am Zentrum für Ambulante Rehabilitation ein integriertes, ambulantes Trainingsprogramm erstellt und wird hypertensiven Patienten angeboten. Dieses Programm kombiniert Bewegungstherapie, Patientenschulung, Entspannungstechniken und Streßmanagement. Bei Bedarf wird individuell eine Psychotherapie angeboten. Die Effektivität des vorgestellten Programms kann durch eine gesteigerte körperliche Leistungsfähigkeit und eine verbesserte Blutdruckregulation trotz signifikanter Reduktion des Medikamentenbedarfs unter Beweis gestellt werden. Gegenwärtig stellen die stark steigenden Medikamentenkosten für die Allgemeinheit Anlaß zur Sorge dar und haben eine teilweise emotional geführte Diskussion um die zukünftige Entwicklung des Gesundheitssystems entfacht. In einer Kosten-Nutzen-Analyse haben wir im weiteren versucht, die Kosten für das beschriebene Trainingsprogramm zu erfassen und haben diese den potentiellen Einsparungen durch reduzierten Medikamentenverbrauch gegenübergestellt. Die vorliegende Arbeit präsentiert eine Zwischenauswertung einer derzeit laufenden Untersuchung und gibt eine Übersicht über die relevante Literatur zum Thema der nicht-phamakologischen Therapie der Hypertonie.

  18. Innovative Therapieoptionen bei therapieresistenter arterieller Hypertonie

    Directory of Open Access Journals (Sweden)

    Linnenweber-Held S

    2012-01-01

    Full Text Available Zwei neue innovative Entwicklungen nicht-medikamentöser Therapieoptionen stehen seit einigen Jahren für die therapieresistente arterielle Hypertonie zur Verfügung: Zum einen kann seit 2003 über die elektrische Stimulierung der Barorezeptoren im Sinus caroticus durch die operative Implantation von Elektroden und einen programmierbaren Pulsgenerator der Blutdruck gesenkt werden. Zum anderen ist seit 2007 die minimalinvasive, kathetergestützte renale Denervierung zur Ablation der sympathischen Nervenfasern in den Nierenarterien möglich. Beide Verfahren reduzieren bei 70–90 % der behandelten Patienten den systolischen Blutdruck um mindestens 10 mmHg. 12 Monate nach Karotisschrittmacherimplantation wird der Blutdruck im Durchschnitt um 30–35/15–20 mmHg gesenkt. Die Ergebnisse für die renale Denervierung liegen im gleichen Bereich, tendenziell aber etwas niedriger. Kontraindikationen für die Barorezeptorstimulation sind eine 50%ige Karotisstenose oder ausgeprägte Plaques. Kontraindikationen für eine renale Denervierung sind eine Nierenarterienstenose oder Z. n. Stenting der Nierenarterie sowie eine Nierenfunktionseinschränkung mit einer geschätzten glomerulären Filtrationsrate (eGFR 45 ml/Min.

  19. Perioperatives Management bei Antiplättchentherapie

    Directory of Open Access Journals (Sweden)

    Mahla E

    2013-01-01

    Full Text Available 10–15 % der Patienten mit akutem Koronarsyndrom müssen sich zeitnah einer aorto-koronaren Bypassoperation unterziehen, 5–25 % der Patienten brauchen eine nichtkardiochirurgische Operation während der ersten 1–5 Jahre nach Stentimplantation. Um Blutungskomplikationen und Transfusionen zu minimieren, wird von europäischen Fachgesellschaften empfohlen, elektive nicht-kardiochirurgische Operationen erst nach vollständiger Dauer der empfohlenen P2Y12-Rezeptorblockertherapie und, sofern vertretbar, unter laufender Therapie mit Aspirin durchzuführen. Bei dringlicher Operationsindikation sollten Clopidogrel und Ticagrelor 5 Tage und Prasugrel 7 Tage präoperativ abgesetzt werden, sofern nicht hohes Ischämierisiko oder Zeichen einer „low clopidogrel responsiveness“ für einen früheren Operationszeitpunkt sprechen. Demgegenüber empfehlen amerikanische Richtlinien, die präoperative Wartezeit an der gemessenen Thrombozytenfunktionshemmung zu orientieren. Die Definition eines „idealen“ Testsystems und eines „Blutungs-Cut-off“ bleiben beide Richtlinien schuldig.

  20. Dosimetry requirements derived from the sterilization standards

    DEFF Research Database (Denmark)

    Miller, A.

    1998-01-01

    The main standards for radiation sterilization, ISO 11137 and EN 552, rest the documentation for the properly executed sterilization process on dosimetry. Both standards describe general requirements to the dosimetry system: The dose measurements must be traceable to national standards, the uncer...

  1. Approaches to the dimensioning of enhanced biological phosphorus elimination systems, taking dynamic simulation into account; Bemessungshinweise zur vermehrten biologischen Phosphorelimination unter Beruecksichtigung der dynamischen Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Scheer, H.

    1997-12-31

    With so many projects either planned or under construction, the question of the dimensioning of sewage treatment plants with enhanced biological phosphorus elimination (BIO-P) is becoming more and more important. A detailed search of literature established in how far dimensioning approaches or models were already available in the spring of 1994. These modelling approaches were critically examined and compared as to their practical applicability by means of parameter and sensitivity studies. For this purpose, they were programmed and the relevance of certain dimensioning parameters to biological phosphorus elimination was studied by means of a pilot plant. (orig./SR) [Deutsch] Der Auslegung von Klaeranlagen mit vermehrter biologischer Phosphorelimination (BIO-P) kommt bei der Vielzahl von Planungs- und Baumassnahmen eine immer wichtigere Bedeutung zu. Inwieweit fuer die Bemessung von Klaeranlagen mit BIO-P im Fruehjahr 1994 bereits auf vorhandene Bemessungsansaetze und -modelle zurueckgegriffen werden konnte, wurde mittels einer detaillierten Literaturstudie, untersucht. Diese Modellansaetze wurden im Hinblick auf ihre praxisorietierte Anwendbarkeit durch Parameter- und Sensitivitaetsstudien kritisch untersucht und verglichen. Hierzu wurden die verschiedenen, zum damaligen Zeitpunkt vorhandenen Ansaetze programmiert und die Auswirkungen wichtiger bemessungsrelevanter Parameter auf die BIO-P anhand einer Modellklaeranlage abgeschaetzt. (orig./SR)

  2. Das Low-T3-Syndrom bei Patienten mit akuter Pankreatitis

    OpenAIRE

    Kömpf, Vera Carolin

    2014-01-01

    Die akute Pankreatitis weist bei einem schweren Verlauf nach wie vor eine hohe Letalität auf. Vor allem bei der akuten nekrotisierenden Pankreatitis kommt es zu Komplikationen wie infizierten Nekrosen und Multiorganversagen. Hinzu kommen weitere Phänomene, die auch bei anderen schweren Erkrankungen auftreten und zu einem ungünstigen Verlauf der Grunderkrankung führen. Das Non-Thyroidal-Illness-Syndrom, das bei vielen intensivpflichtigen Erkrankungen auftritt, ist eines davon. In der vorlie...

  3. Über die Rückbildung der Kiemenbogen bei den Selachii

    NARCIS (Netherlands)

    Versluys, J.

    1922-01-01

    Das Vorkommen von sieben Kiemenbogen bei Heptanchus, sechs bei Hexanchus, Chlamydoselachus und Pliotrema (REGAN, 1908), und von nur fünf bei den übrigen Selachii weist auf Rückbildung der Zahl der Kiemenbogen innerhalb der Selachii hin. Dadurch entsteht die Frage wie diese Verringerung der Zahl der

  4. Nichterkennen von Vorhofflimmern bei Patienten mit kardialer Resynchronisationstherapie

    Directory of Open Access Journals (Sweden)

    Strohmer B

    2005-01-01

    Full Text Available Obwohl eine Intoleranz der kardialen Resynchronisationstherapie (CRT unüblich ist, sollten entsprechende Symptome auf ihre Ursache hin genau abgeklärt werden. Atriale Tachyarrhythmien (AT werden bei Patienten mit chronischer Herzinsuffizienz relativ häufig beobachtet. Dieser Bericht beschreibt ein rhythmologisches Problem, welches oft unerkannt bleibt und in unserem CRTKollektiv bei knapp 8 % der Patienten aufgetreten ist. Paroxysmales Vorhofflattern wurde durch den CRT-Schrittmacher nicht erkannt, da jede zweite Flatterwelle exakt mit der atrialen Ausblendzeit (PVAB = postventrikuläres atriales Blanking zusammenfiel. Dies führte zu einem Versagen der Mode-Switch-Funktion durch Nichterkennung von stabilem Vorhofflattern, welches mit sehr stabiler Zykluslänge auftrat. Dieses sog. "2:1-lock-in"-Phänomen resultierte in rascher und anhaltender biventrikulärer Stimulation, welche sich bei den betroffenen Patienten klinisch als unangenehmes Herzklopfen mit zunehmender Atemnot bemerkbar machte.

  5. Head injuries in children; Schaedel-Hirn-Trauma bei Kindern

    Energy Technology Data Exchange (ETDEWEB)

    Zimmer, A.; Reith, W. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany)

    2009-10-15

    Trauma is the reason for 40-60% of emergency callouts concerning children. Approximately half of the children have head injuries. As for adults early recognition of findings indicating an intervention are decisive for the prognosis. In children head injury can be divided into three categories: birth trauma, accidental and non-accidental trauma. This article concentrates on accidental trauma with respect to characteristics of causes, epidemiology, mechanisms of accidents and illustrated morphological findings. (orig.) [German] In 40-60% der Faelle ist ein Trauma die Ursache fuer Noteinsaetze bei Kindern. Dabei weist ca. die Haelfte der Verletzten ein Schaedel-Hirn-Trauma (SHT) auf. Wie bei Erwachsenen ist das fruehzeitige Erkennen interventionspflichtiger Befunde entscheidend fuer die Prognose. Man unterscheidet bei Kindern 3 Formen des SHT: das Geburtstrauma, das akzidentelle und das nichtakzidentelle Trauma. Der folgende Artikel befasst sich mit dem akzidentellen Trauma, wobei Besonderheiten hinsichtlich der Ursachen, der Epidemiologie, des Unfallmechanismus und der bildmorphlogischen Befunde herausgearbeitet werden. (orig.)

  6. Spect in epilepsy; SPECT bei Anfallsleiden

    Energy Technology Data Exchange (ETDEWEB)

    Feistel, H. [Nuklearmedizinische Klinik mit Poliklinik und Neurologische Klinik, Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany); Weis, M. [Nuklearmedizinische Klinik mit Poliklinik und Neurologische Klinik, Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany); Michalik, K. [Nuklearmedizinische Klinik mit Poliklinik und Neurologische Klinik, Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany); Schueler, P. [Nuklearmedizinische Klinik mit Poliklinik und Neurologische Klinik, Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany); Platsch, G. [Nuklearmedizinische Klinik mit Poliklinik und Neurologische Klinik, Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany); Stefan, H. [Nuklearmedizinische Klinik mit Poliklinik und Neurologische Klinik, Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany); Wolf, F. [Nuklearmedizinische Klinik mit Poliklinik und Neurologische Klinik, Friedrich-Alexander-Univ. Erlangen-Nuernberg, Erlangen (Germany)

    1997-06-01

    Fokuslokalisation genutzt werden. In diesem Zusammenhang wird nach dem `Erlanger Modell` auch das periiktuale SPECT eingesetzt, d.h. die Injektion des Tracers geschieht im Anfall (iktuales SPECT), unmittelbar nach Sistieren des Anfalls (postiktual) oder im anfallsfreien Intervall (interiktual). Die iktuale oder postiktuale Applikation des Tracers setzt eine eingespielte Zusammenarbeit zwischen neurologischer und nuklearmedizinischer Abteilung voraus, die unter Beachtung der Strahlenschutzvorschriften im Monitoringzentrum entstehen muss. Im Fall der Temporallappenepilepsie laesst sich durch Serienaufnahmen zeigen, dass zu Anfallsbeginn der Schlaefenlappen grossflaechig hyperperfundiert sein kann bei parietaler Minderdurchblutung, dass der Herd in den ersten beiden Minuten nach Anfallsende am engsten markiert abgebildet wird und bei spaeterer Injektion nur noch minderperfundiert erscheint. Im Fall der Frontallappenepilepsien ist eine fruehe Injektion moeglichst innerhalb von 40 Sekunden anzustreben, andernfalls kann eine Anfallspropagation in distante Hirnareale, auch nach kontralateral, stattfinden. Extraemporale Epilepsien sind haeufig mit Missbildung oder Trauma vergesellschaftet und schwer kategorisierbar. In schwierigen Faellen kann durch die Rezeptorszintigraphie mit z.B. Iomazenil der Fokus in Form einer kalten Gewebslaesion als Ausdruck der gestoerten neuronalen Integritaet lokalisiert werden. (orig.)

  7. Dimensioning of municipal sewage treatment plants. Fundamentals, specifications and examples of the dimensioning of biological and further sewage treatment plants; Bemessung von kommunalen Klaeranlagen. Grundlagen, Bemessungsansaetze und -beispiele der biologischen und weitergehenden Abwasserbehandlung

    Energy Technology Data Exchange (ETDEWEB)

    Guenthert, F.W.; Teichmann, H. [Universitaet der Bundeswehr Muenchen, Neubiberg (Germany); Baumann, P.; Dorias, B. [Stuttgart Univ. (Germany); Bever, J. [Durchschlag und Bever Ingenieurgesellschaft, Oberhausen (Germany); Gschloessl, T.; Schleypen, P. [Bayerisches Landesamt fuer Wasserwirtschaft, Muenchen (Germany); Kapp, H. [Fachhochschule Biberach an der Riss (Germany); Maier, W. [iat.-Ingenieurberatung fuer Abwassertechnik, Stuttgart (Germany); Matsche, N. [Technische Univ., Vienna (Austria); Stein, A.; Teichgraeber, B. [Emschergenossenschaft und Lippeverband, Essen (Germany); Steinle, E.; Strohmeier, A. [Fachhochschule Aachen (Germany)

    1998-12-31

    On the basis of process-engineering knowledge and scientific fact, criteria for the dimensioning and planning of biological and further sewage treatment are pointed out. Legal aspects as well as factors relevant to construction, operation and economy are extensively considered. The book informs on the following: Fundamentals, methods, dimensioning and simulation of activated sludge processes; trickling filter techniques with nitrogen elimination and immersed-packed-bed techniques; chemical and biological phosphorus elimination; sedimentation tanks and filters.- Dimensioning and planning examples permit readers to deepen their knowledge and gain more competence. Reference is made in each section to the corresponding instruction sheets of the Abwassertechnische Vereinigung, EU recommendations, and EN as well as DIN standards. (orig.) [Deutsch] Es werden, ausgehend von den verfahrenstechnischen und naturwissenschaftlichen Grundlagen, die Bemessungs- und Planungskriterien der biologischen und weitergehenden Abwasserbehandlung dargelegt. Der rechtliche Bezug sowie konstruktive, betriebliche und wirtschaftliche Aspekte werden dabei ausfuehrlich mit beruecksichtigt. Das Buch informiert ueber: - Grundlagen, Verfahren, Bemessungen und Simulation von Belebungsanlagen - Tropfkoerperverfahren mit Stickstoffelimination sowie getauchte Festbettverfahren - chemische und biologische Phosphorelimination - Nachklaerbecken und Filtrationsanlagen. Anhand von Bemessungs- und Planungsbeispielen kann der Leser vertiefte Kenntnisse fuer seine Taetigkeit erwerben. In den jeweiligen Abschnitten werden die entsprechenden Arbeitsblaetter der Abwassertechnischen Vereinigung, EG-Richtlinien, EN und DIN-Normen beruecksichtigt. (orig.)

  8. ESR dosimetry using eggshells and tooth enamel for accidental dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Oka, Toshihide; Yamanaka, Chihiro; Ikeya, Motoji [Department of Earth and Space Science, Faculty of Science, Osaka Univ., Toyonaka, Osaka (Japan)

    1997-07-01

    The CO{sub 2}{sup -} signal of eggshells showed a good dose linearity and was appropriate in the wide dose range from 1 to 10 kGy, while ESR signal of CO{sub 2}{sup -} in sea and fresh water shells were saturated at a dose od below 10 kGy. The minimum detectable dose and G-value of CO{sub 2}{sup -} in eggshells were estimated 0.3 Gy and 0.28, respectively. The lifetime of CO{sub 2}{sup -} in eggshells could not be determined exactly because of overlapping organic signals, however it is still sufficiently long for practical use as ESR dosimeter materials. Various bird`s or reptile`s eggshells would be available as natural retrospective ESR dosimeter materials after nuclear accidents. Eggshells will be useful for the food irradiation dosimetry in the dose range of about a few kGy. Tooth enamel is one of the most useful dosimeter materials in public at a accident because of its high sensitivity. ESR dosimetry will replace TLD in near future if the cost of an ESR reader is further reduced . (author)

  9. Radiation dosimetry by potassium feldspar

    Indian Academy of Sciences (India)

    Arun Pandya; S G Vaijapurkar; P K Bhatnagar

    2000-04-01

    The thermoluminescence (TL) properties of raw and annealed feldspar have been studied for their use in gamma dosimetry. The raw gamma exposed feldspar shows glow peaks at 120°C and 319°C. Gamma dose beyond 500 cGy can be measured without any significant fading even after 40 days of termination of exposure. The annealed feldspar shows a glow peak at 120°C after gamma exposure. This peak can be used to measure gamma doses beyond 25 cGy when the TL is measured after 24 h from termination of exposure.

  10. Relocation of the Dosimetry Service

    CERN Multimedia

    2007-01-01

    The Dosimetry Service is moving from Building 24 to Building 55 and will therefore be closed on Friday, 30 March. From Monday, 2 April onwards you will find us in Building 55/1-001. Please note that we cannot exclude problems with Internet connections on that day and are therefore unable to guarantee normal service. The Service's opening hours and telephone number will not change as a result of the move: Open from 8.30 - 12.00. Closed in the afternoons. Tel. 7 2155

  11. Neuropsychologische und psychiatrische Komorbiditäten bei Epilepsien

    Directory of Open Access Journals (Sweden)

    Lehner-Baumgartner E

    2009-01-01

    Full Text Available Neuropsychologische Beeinträchtigungen stellen ein gravierendes Problem für viele Epilepsiepatienten dar und werden im Wesentlichen durch die 3 folgenden Faktoren verursacht und beeinflusst: (1 Morphologische Faktoren – Lokalisation und Art der epileptogenen Läsion. Zudem können umschriebene Läsionen auch zu funktionellen Beeinträchtigungen in von der Läsion entfernten Hirnregionen führen, was durch eine Störung von funktionellen Netzwerken erklärt werden kann. (2 Klinische und demographische Faktoren (Alter zu Erkrankungsbeginn, Erkrankungsdauer, Anfallsfrequenz und -schwere, Geschlecht. (3 Funktionelle Faktoren (antikonvulsive Medikation, allfällige psychiatrische Komorbiditäten, Effekte von Anfällen und interiktale epileptiforme Entladungen. Psychiatrische Erkrankungen (Depressionen, Psychosen und Angststörungen treten bei Epilepsiepatienten signifikant häufiger auf als in der Allgemeinbevölkerung und als bei anderen chronischen Erkrankungen. Psychiatrische Störungen können entweder in einer fixen zeitlichen Beziehung zu den Anfällen auftreten (präiktale, iktale und postiktale psychiatrische Störungen oder sich unabhängig vom Auftreten der Anfälle manifestieren (interiktale psychiatrische Störung. Die Depression stellt die häufigste psychiatrische Begleiterkrankung bei Epilepsie dar, zudem ist eine Depression ein Risikofaktor für das Neu- Auftreten einer Epilepsie. Diese bidirektionale Beziehung könnte durch gemeinsame Pathomechanismen beider Erkrankungen erklärt werden. Obwohl das Vorliegen und der Schweregrad einer Depression die wichtigsten Prädiktoren für die Lebensqualität bei Epilepsiepatienten darstellen, werden Depressionen bei Epilepsiepatienten unterdiagnostiziert und unterbehandelt. Eine psychopharmakologische Behandlung sollte bei Vorliegen einer Begleitdepression unverzüglich initiiert werden, das epileptogene Potenzial von Antidepressiva stellt dabei ein vernachlässigbares Risiko dar.

  12. Die Chirurgie der abdominellen Aorta bei Dissektionen, Aneurysmen und Ruptur

    Directory of Open Access Journals (Sweden)

    Veit FH

    2001-01-01

    Full Text Available Das chirurgische Standardverfahren in der Behandlung geschlossener oder rupturierter abdomineller Aneurysmen ist die "offene" Dissektionsresektion. Mit diesem invasiven konventionellen Verfahren sind alle Formen abdomineller Aneurysmen behandelbar. Bei Patienten mit niedrigem Risikoprofil ist die perioperative Mortalität gering und das Langzeitergebnis ausgezeichnet. Die transfemorale minimal invasive Implantation von Endoprothesen ist bei ausgewählten Patienten mit geeigneter Anatomie eine befriedigende Alternative. Die perioperative Mortalität ist auch beim Hochrisikopatienten gering. Der ungewisse Langzeitverlauf erfordert eine lebenslange Observanz des Aneurysmas.

  13. An Automated Biological Dosimetry System

    Science.gov (United States)

    Lorch, T.; Bille, J.; Frieben, M.; Stephan, G.

    1986-04-01

    The scoring of structural chromosome aberrations in peripheral human blood lymphocytes can be used in biological dosimetry to estimate the radiation dose which an individual has received. Especially the dicentric chromosome is a rather specific indicator for an exposure to ionizing radiation. For statistical reasons, in the low dose range a great number of cells must be analysed, which is a very tedious task. The resulting high cost of a biological dose estimation limits the application of this method to cases of suspected irradiation for which physical dosimetry is not possible or not sufficient. Therefore an automated system has been designed to do the major part of the routine work. It uses a standard light microscope with motorized scanning stage, a Plumbicon TV-camera, a real-time hardware preprocessor, a binary and a grey level image buffer system. All computations are performed by a very powerful multi-microprocessor-system (POLYP) based on a MIMD-architecture. The task of the automated system can be split in finding the metaphases (see Figure 1) at low microscope magnification and scoring dicentrics at high magnification. The metaphase finding part has been completed and is now in routine use giving good results. The dicentric scoring part is still under development.

  14. Path forward for dosimetry cross sections

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, P.J. [Sandia National Laboratories, Albuquerque, NM 87185-1146 (United States); Peters, C.D. [Sandia Staffing Alliance, Albuquerque, NM 87110 (United States)

    2011-07-01

    In the 1980's the dosimetry community embraced the need for a high fidelity quantification of uncertainty in nuclear data used for dosimetry applications. This led to the adoption of energy-dependent covariance matrices as the accepted manner of quantifying the uncertainty data. The trend for the dosimetry community to require high fidelity treatment of uncertainty estimates has continued to the current time where requirements on nuclear data are codified in standards such as ASTM E 1018. This paper surveys the current state of the dosimetry cross sections and investigates the quality of the current dosimetry cross section evaluations by examining calculated-to-experimental ratios in neutron benchmark fields. In recent years more nuclear-related technical areas are placing an emphasis on uncertainty quantification. With the availability of model-based cross sections and covariance matrices produced by nuclear data codes, some nuclear-related communities are considering the role these covariance matrices should play. While funding within the dosimetry community for cross section evaluations has been very meager, other areas, such as the solar-related astrophysics community and the US Nuclear Criticality Safety Program, have been supporting research in the area of neutron cross sections. The Cross Section Evaluation Working Group (CSEWG) is responsible for the creation and maintenance of the ENDF/B library which has been the mainstay for the reactor dosimetry community. Given the new trends in cross section evaluations, this paper explores the path forward for the US nuclear reactor dosimetry community and its use of the ENDF/B cross-sections. The major concern is maintenance of the sufficiency and accuracy of the uncertainty estimate when used for dosimetry applications. The two major areas of deficiency in the proposed ENDF/B approach are: 1) the use of unrelated covariance matrices in ENDF/B evaluations and 2) the lack of 'due consideration' of

  15. Introduction to radiological physics and radiation dosimetry

    CERN Document Server

    Attix, Frank Herbert

    2004-01-01

    A straightforward presentation of the broad concepts underlying radiological physics and radiation dosimetry for the graduate-level student. Covers photon and neutron attenuation, radiation and charged particle equilibrium, interactions of photons and charged particles with matter, radiotherapy dosimetry, as well as photographic, calorimetric, chemical, and thermoluminescence dosimetry. Includes many new derivations, such as Kramers X-ray spectrum, as well as topics that have not been thoroughly analyzed in other texts, such as broad-beam attenuation and geometrics, and the reciprocity theorem

  16. Sportmedizinische Aspekte des Judo bei Kindern und Jugendlichen : Auswertung von Sportverletzungen mit Konsequenzen für Trainings- und Wettkampfbetreuung

    OpenAIRE

    Erdmann, Ute

    2000-01-01

    In einer aktuell erhobenen Studie wurde das Auftreten von Sportverletzungen bei Kindern und Jugendlichen im Judo auf Breitensportebene ausgewertet. Bei Wettkampf, Lehrgang und Training wurden 129 Verletzungen bei 107 Verletzten erfasst. Es ergab sich eine Verletzungsinzidenz von 9,6 % bei Wettkämpfen und 37,5 % bei Lehrgängen. Nur 4,7 % der 129 Verletzungen waren schwer, darunter keine Lehrgangsverletzung. In der Gesamtstatistik dominierten Verletzungen an den unteren Extremitäten mi...

  17. Fertilitätsprotektion bei onkologischen Erkrankungen der Frau

    Directory of Open Access Journals (Sweden)

    von Wolff M

    2009-01-01

    Full Text Available Die steigenden Überlebensraten und die zunehmende Bedeutung der Lebensqualität nach einer Krebserkrankung haben den Fertilitätserhalt bei zytotoxischen Therapien in den Fokus der Aufmerksamkeit gerückt. Fortschritte in der Reproduktionsmedizin und die Bildung von regionalen, nationalen und internationalen interdisziplinären Netzwerkstrukturen ermöglichen inzwischen auch bei Frauen die effektive Durchführung von fertilitätsprotektiven Techniken. Angeboten werden einzeln oder in Kombination die ovarielle Stimulation und Kryokonservierung von unfertilisierten und fertilisierten Oozyten, die Entnahme und Kryokonservierung von Ovargewebe und die Gabe von GnRH-Analoga. Die Wahl der Methode muss jedoch insbesondere bei Frauen interdisziplinär und ausschließlich auf dem Boden einer großen reproduktionsmedizinischen Erfahrung gestellt werden. Das Netzwerk FertiPROTEKT (http://www.fertiprotekt.de umfasst spezialisierte Zentren und bietet Unterstützung bei der Beratung der Patienten, der Auswahl, Evaluation und Optimierung der z. T. noch nicht voll etablierten Techniken

  18. Grundlagen und Zahlen zur genetischen Beratung bei komplexen Epilepsien

    Directory of Open Access Journals (Sweden)

    Zimprich F

    2009-01-01

    Full Text Available Aufgrund der erhöhten genetischen Belastung bei komplexen Epilepsieformen suchen Angehörige oder Patienten oft Rat zur Ermittlung des Erkrankungsrisikos für weitere Familienmitglieder. Im vorliegenden Artikel wird versucht, Grundlagen sowie Fakten aus der Literatur zur Beantwortung dieser Frage bereitzustellen.

  19. Anticholinergika bei überaktiver Blase und benignem Prostatasyndrom

    Directory of Open Access Journals (Sweden)

    Gabuev A

    2007-01-01

    Full Text Available Das klinische Bild des benignen Prostatasyndroms (BPS ist vielfältig. Standardmäßig werden die Patienten mit benigner prostatischer Obstruktion operativ behandelt. Ein wesentlicher Anteil der betroffenen Männer leidet vorwiegend unter Drangsymptomen wie Pollakisurie und gehäuftem imperativen Harndrang mit oder ohne Harninkontinenz. Nach dem Versagen der primären konservativen Behandlung mit selektiven Alpha-1- Adrenoblockern und/oder 5-alpha-Reduktasehemmern in dieser Patientengruppe (Non-Responder wird häufig die Indikation zu weniger akzeptablen invasiven Therapieoptionen gestellt. Die Ergebnisse von internationalen multizentrischen Studien zur Wirkung von Anticholinergika bei Patienten mit dem Syndrom „überaktive Blase“ zeigten deren Effizienz und günstiges Nebenwirkungsprofil. Dies führte zur kritischen Betrachtung des Problems der Anwendung von Anticholinergika bei benigner Hyperplasie der Prostata als „klassische“ Kontraindikation und zu einer breiteren Indikationsstellung zur konservativen Therapie bei Non-Respondern. Die vorliegende Analyse der aktuellen Publikationen zur Anwendung von Anticholinergika zeigt, daß ein selektioniertes Patientenkollektiv mit irritativen Beschwerden bei BPS von dieser Therapie profitieren kann. Eine Tendenz zur Entwicklung des akuten Harnverhaltes konnte nicht eindeutig nachgewiesen werden. Eine kontrollierte Anwendung von Anticholinergika in Kombination mit selektiven Alpha-1-Blockern scheint möglich zu sein. Weitere Studien auf diesem Gebiet müssen noch nicht geklärte Fragen beantworten und die Wirkung von neuen anticholinergen Substanzen wie M3-selektiven Antimuskarinika oder Fesoterodin prüfen.

  20. Nagelbefall kann bei Patienten mit Psoriasis auf eine Enthesiopathie hinweisen.

    Science.gov (United States)

    Castellanos-González, Maria; Joven, Beatriz Esther; Sánchez, Julio; Andrés-Esteban, Eva María; Vanaclocha-Sebastián, Francisco; Romero, Pablo Ortiz; Díaz, Raquel Rivera

    2016-11-01

    Obwohl subklinische Enthesiopathie ein gut etabliertes diagnostisches Merkmal der Psoriasisarthritis (PsA) ist, wird sie häufig übersehen, da viele Patienten asymptomatisch sind. Gäbe es klinische Hinweise auf das Vorliegen einer Enthesiopathie, würde dies den Klinikern die Möglichkeit eröffnen, eine PsA frühzeitig zu diagnostizieren. Es wurde eine monozentrische prospektive Studie mit insgesamt 90 Psoriasis-Patienten durchgeführt, um mittels Ultraschall das Vorliegen von Enthesenanomalien zu untersuchen und eine Korrelation mit dem Befall der Nägel festzustellen. Enthesenanomalien wurden bei 23 Patienten (25,5 %) gefunden, von denen 19 (82,6 %) Nagelbefall aufwiesen. Bei 4 Patienten waren die Nägel nicht betroffen. Enthesiopathie lag bei 31,1 % (19/61) der Patienten mit Onychopathie vor, von den Patienten ohne Nagelbefall litten nur 13,8 % (4/29) an Enthesiopathie (p = 0,07). Zwischen dem Target-NAPSI-Score und dem Vorliegen einer Enthesiopathie bestand eine signifikante Korrelation. Eine signifikante Korrelation bestand darüber hinaus auch zwischen dem Vorliegen einer Enthesiopathie und der Anzahl der betroffenen Nägel (p = 0,035). Klinische Belege für eine Onychopathie können der Schlüssel für die frühe Diagnose einer Enthesiopathie bei Psoriasis-Patienten sein. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  1. Teaching Pablo Neruda and Bei Dao: The Lens of Leaving.

    Science.gov (United States)

    Lichtenstein, Amanda Leigh

    2003-01-01

    Explains how the author invites young poets to tromp through the landscape of their minds in search of all things broken by using two of her favorite poems: Pablo Neruda's "Ode to Broken Things" and Bei Dao's "Comet." Outlines how the students write their own poems dealing with loss. Notes that for poets, a heap of broken images becomes an immense…

  2. Radiological diagnosis in epilepsy; Radiologische Diagnostik bei Epilepsie

    Energy Technology Data Exchange (ETDEWEB)

    Ostertun, B. [Radiologische Universitaetsklinik, Bonn (Germany). Magnetresonanztomographie

    1999-03-01

    Results: Hippocampal sclerosis, the most frequent cause of focal epilepsy, can be detected with 90-98% sensitivity by visual analysis and quantitative signal and volume measurement of the hippocampi in high-resolution coronal T{sub 2}-weighted MR images. Benign tumors, such as gangliogliomas and dysembryoplastic neuoepithelial tumors (DNT), as well as cortical dysplasias are frequently composed of cystic and solid parts, which may show calcification, but never edema. Bloodbrain-barrier disruption as seen in approximately 40% of the benign tumors are the only feature that allows to differentiate them from non-neoplastic dysplasias. In rare cases of totally calcified lesions, CT may be the only diagnostic imaging modality. Proton-density-weighted or FLAIR imaging is essential for the detection of small solid cortical lesion components, because they provide sufficient contrast with adjacent CSF. T{sub 1}-weighted inversion recovery images are most sensitive for the detection of migration and gyration abnormalities. The depiction of calcified lesions and hemosiderin deposits after trauma is most efficient with T{sub 2}* weighted gradient echo sequences. Conclusions: With further rapid improvent of high resolution MRI techniques, the near future will probably show that nearly 100% of focal epilepsies are caused by structural brain abnormalities. With refined imaging techniques applied, the sensitivity of neuroradiological evaluation is 90% at present. Therefore presurgical MRI plays a key role in epilespy surgery. (orig.) [Deutsch] Ergebnisse: Ammonshornsklerosen, die haeufigste Ursache fokaler Epilepsien, werden bei Anwendung hochaufloesender koronarer T{sub 2}-gewichteter Sequenzen durch visuelle Beurteilung und quantitative Messungen von Signal und Volumen der Hippocampi mit 90-98% Sensitivitaet nachgewiesen. Gutartige Tumoren wie Gangliogliome und dysembryoplastische neuroepitheliale Tumoren (DNT) sowie glioneuronale Hamartien weisen gehaeuft zystische Komponenten

  3. Differenzielle pharmakologische Rückfallprophylaxe bei Alkoholabhängigkeit

    Directory of Open Access Journals (Sweden)

    Mutschler J

    2011-01-01

    Full Text Available Alkoholismus stellt weltweit ein großes medizinisches Problem mit weitreichenden ökonomischen und sozialen Folgen dar. Neben psychotherapeutischen Verfahren stehen seit Kurzem auch effektive medikamentöse Behandlungsmöglichkeiten zur Verfügung. Aktuelle Studienergebnisse geben Hinweise darauf, dass Symptome wie Angst, Depression und vor allem der starke Wunsch bzw. Zwang, Alkohol zu konsumieren („Craving“ die Wirksamkeit einer pharmakologischen Rückfallprophylaxe beeinflussen. Weiterhin könnten typologische Differenzierung und Genotypisierung hilfreiche Prädiktoren für eine medikamentöse Rückfallprophylaxe bei der Alkoholabhängigkeit sein. Suchtdruck („Craving“ stellt einen der Hauptgründe für Rückfälle im Rahmen der Alkoholabhängigkeit dar. Es können aktuell drei unterschiedliche Formen von Suchtdruck unterschieden werden: Reward Craving (Belohnung, Relief Craving (Erleichterung/Entspannung und Obsessive Craving (zwanghaft. Für jede Form von Craving werden differenzierbare zentralnervöse pathophysiologische Merkmale vermutet; somit existieren mehrere potenzielle pharmakodynamische Angriffspunkte für Anti-Craving-Substanzen. Die seit über 10 Jahren für die Behandlung von Craving bei der Alkoholabhängigkeit verfügbaren Substanzen sind Acamprosat und Naltrexon. Diese Substanzen sind allerdings nicht bei allen Patienten gleichermaßen wirksam. Allgemein scheint die pharmakotherapeutische Rückfallprophylaxe wirksamer bei Patienten mit einem frühen Beginn der Alkoholabhängigkeit. Bei Patienten mit im Vordergrund stehendem Relief Craving scheint Acamprosat besser zu wirken, bei Patienten mit überwiegendem Reward Craving zeigt sich eine bessere Wirksamkeit für Naltrexon. Disulfiram, die neben Acamprosat und Naltrexon dritte und am längsten zugelassene rückfallprophylaktische Substanz, zeigt Vorteile bei Patienten mit impulsivem Trinkverhalten und ausgeprägtem Kontrollverlust. Weitere klinische Studien unter

  4. Vom Fang bis zum Datensatz - hilfreiche Anmerkungen für ein erfolgreiches Sammeln : Bericht über den COLEO-Workshop am 15. März 2003 in der Biologischen Station Urdenbacher Kämpe

    OpenAIRE

    Stöcker, Michael

    2009-01-01

    Wie schon in den vergangenen Jahren fand auch in diesem Jahr wieder ein praxisorientierter Workshop im Anschluss an die COLEO‑ Jahreshauptversammlung in der Urdenbacher Kämpe bei Monheim statt. Im Mittelpunkt des diesjährigen Workshops standen Fragen, Tipps und Hilfestellungen aus der praktischen Coleopterologie. Intention und Ziel war es, jungen Kollegen und Neueinsteigern Hilfen in diesen allgemeinen und grundlegenden Fragen geben.

  5. Pneumonia in immunosuppressed patients; Pneumonien bei immunsupprimierten Patienten

    Energy Technology Data Exchange (ETDEWEB)

    Solyanik, O.; Gaass, T.; Hellbach, K. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer klinische Radiologie, Muenchen (Germany); Dinkel, J. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer klinische Radiologie, Muenchen (Germany); Comprehensive Pneumology Center Munich (CPC-M), Muenchen (Germany)

    2017-01-15

    Pulmonary infections are a common complication in immunosuppressed patients with a frequently fatal prognosis despite modern prophylactic therapy. An early and correct diagnosis is important for initiation of the appropriate therapy. Chest radiography is the preferred initial imaging examination but is not accurate enough for the detection of pulmonary infections in immunosuppressed patients. Pneumonia is caused by a broad spectrum of pathogens in immunocompromised patients. In addition to imaging, the clinical history and epidemiology also play an important role in the diagnostics. Using epidemiological and anamnestic information, computed tomography (CT) shows a significantly better sensitivity and specificity particularly for the diagnosis of atypical forms of pneumonia. Due to the exact imaging of the different infiltration patterns CT provides an increased sensitivity with respect to the etiological classification of pulmonary infections. This article reviews in particular the radiological findings of commonly occurring pulmonary infections in immunosuppressed patients. (orig.) [German] Pneumonien bei immunsupprimierten Patienten sind haeufige Komplikationen, die trotzt moderner Prophylaxe toedlich verlaufen koennen. Eine korrekte Diagnose ist daher von entscheidender Bedeutung, um die richtige Therapie einleiten zu koennen. Die Roentgenthoraxaufnahme ist selten spezifisch genug fuer die genaue Einordnung atypischer Pneumonien in Folge einer Immunsuppression. Pneumonien unter Immunsuppression werden durch ein sehr breites Erregerspektrum verursacht. Eine wichtige Rolle bei der Diagnosefindung spielen neben der Bildgebung auch die klinische Anamnese und Epidemiologie. Mithilfe der klinischen Anamnese und Epidemiologie bietet die Computertomographie (CT) bei immunsupprimierten Patienten zum einen eine erhoehte Sensitivitaet bei der Detektion insbesondere atypischer Pneumonien. Zum anderen weist die CT durch die exakte Abbildung unterschiedlicher Infiltratmuster

  6. Protocol for emergency EPR dosimetry in fingernails

    OpenAIRE

    Trompier, F; Kornak, L.; Calas, C.; Romanyukha, A.; LeBlanc, B.; Mitchell, C. A.; Swartz, H M; Clairand, I.

    2007-01-01

    There is an increased need for after-the-fact dosimetry because of the high risk of radiation exposures due to terrorism or accidents. In case of such an event, a method is needed to make measurements of dose in a large number of individuals rapidly and with sufficient accuracy to facilitate effective medical triage. Dosimetry based on EPR measurements of fingernails potentially could be an effective tool for this purpose. This paper presents the first operational protocols for EPR fingernail...

  7. Development of radiation biological dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Chul Koo; Kim, Tae Hwan; Lee, Yun Sil; Son, Young Sook; Kim, Soo Kwan; Jang, Won Suk; Le, Sun Joo; Jee, Young Heun; Jung, Woo Jung

    1999-04-01

    Up until now, only a few methods have been developed for radiation biological dosimetry such as conventional chromosome aberration and micronucleus in peripheral blood cell. However, because these methods not only can be estimated by the expert, but also have a little limitation due to need high technique and many times in the case of radiation accident, it is very difficult to evaluate the absorbed dose of victims. Therefore, we should develop effective, easy, simple and rapid biodosimetry and its guideline (triage) to be able to be treated the victims as fast as possible. We established the premature chromosome condensation assay and apoptotic fragment assay which was the significant relationship between dose and cell damages to evaluate the irradiation dose as correct and rapid as possible using lymphocytes and crypt cells, and compared with conventional chromosome aberration assay and micronuclei assay.

  8. Advanced materials in radiation dosimetry

    CERN Document Server

    Bruzzi, M; Nava, F; Pini, S; Russo, S

    2002-01-01

    High band-gap semiconductor materials can represent good alternatives to silicon in relative dosimetry. Schottky diodes made with epitaxial n-type 4 H SiC and Chemical Vapor Deposited diamond films with ohmic contacts have been exposed to a sup 6 sup 0 Co gamma-source, 20 MeV electrons and 6 MV X photons from a linear accelerator to test the current response in on-line configuration in the dose range 0.1-10 Gy. The released charge as a function of the dose and the radiation-induced current as a function of the dose-rate are found to be linear. No priming effects have been observed using epitaxial SiC, due to the low density of lattice defects present in this material.

  9. Hormonimplantate zur Kontrazeption bei der Frau

    Directory of Open Access Journals (Sweden)

    Rabe T

    2013-01-01

    Full Text Available Hormonimplantate sind Kontrazeptiva, die, subdermal implantiert, über einen längeren Zeitraum eine zuverlässige Kontrazeption bieten. Als Träger werden inerte oder biologisch abbaubare Stäbchen oder Kapseln verwendet, die das jeweilige Steroid kontinuierlich über einen längeren Zeitraum freisetzen. Seit 1966 forscht das Population Council in New York an der Langzeitkontrazeption mit subdermalen Hormonimplantaten. Diese bestehen aus einem oder mehreren kleinen, flexiblen Stäbchen oder aus einer Kapsel, die unter die Haut des Oberarmes eingesetzt werden. Sie setzen dort je nach Produkt die Gestagene Megestrolazetat, Norethindron, Norgestrinon oder Etonogestrel über einen Zeitraum von 1–5 Jahren frei. Norplant® bestand aus 6 Stäbchen. Jedes dieser Stäbchen enthält 36 mg Levonorgestrel. Die Wirkdauer dieser 6 Stäbchen betrug insgesamt 5 Jahre; seit 2008 wird es nicht mehr vermarktet. Norplant II® (Jadelle®, das Nachfolgeprodukt von Norplant®, besteht aus 2 flexiblen Silikonstäbchen (43 mm × 2,5 mm mit jeweils 75 mg Levonorgestrel und hat ebenfalls eine Wirkdauer von 5 Jahren. In China ist das gleiche Produkt unter dem Namen Sinoplant im Handel. Implanon® ist ein etonogestrelfreisetzendes Hormonimplantat, das im Jahr 2000 von Organon (jetzt MSD zugelassen wurde. Das Stäbchen von 4 cm Länge und 2 mm Durchmesser besteht aus 40 % Ethylenvinylacetat (EVA und 60 % 68-mg-Etonogestrel (3-Keto-Desogestrel. Die Wirkdauer beträgt nach subdermaler Implantation 3 Jahre. Der Pearl-Index liegt nach Herstellerangaben unter 0,1. Insofern zählt es zu den sicheren Verhütungsmethoden. Der Wirkspiegel sinkt in Abhängigkeit vom Körpergewicht mit der Zeit ab. Klinische Erfahrungen mit Implanon® bei adipösen Frauen im 3. Jahr der Anwendung sind beschränkt. Eine Voraussetzung für die Zuverlässigkeit ist die korrekte Einlage. Unter Implanon® gibt es Fälle, in denen das Stäbchen nicht korrekt eingelegt wurde. Dies kann dazu führen, dass

  10. Uncertainty in 3D gel dosimetry

    Science.gov (United States)

    De Deene, Yves; Jirasek, Andrew

    2015-01-01

    Three-dimensional (3D) gel dosimetry has a unique role to play in safeguarding conformal radiotherapy treatments as the technique can cover the full treatment chain and provides the radiation oncologist with the integrated dose distribution in 3D. It can also be applied to benchmark new treatment strategies such as image guided and tracking radiotherapy techniques. A major obstacle that has hindered the wider dissemination of gel dosimetry in radiotherapy centres is a lack of confidence in the reliability of the measured dose distribution. Uncertainties in 3D dosimeters are attributed to both dosimeter properties and scanning performance. In polymer gel dosimetry with MRI readout, discrepancies in dose response of large polymer gel dosimeters versus small calibration phantoms have been reported which can lead to significant inaccuracies in the dose maps. The sources of error in polymer gel dosimetry with MRI readout are well understood and it has been demonstrated that with a carefully designed scanning protocol, the overall uncertainty in absolute dose that can currently be obtained falls within 5% on an individual voxel basis, for a minimum voxel size of 5 mm3. However, several research groups have chosen to use polymer gel dosimetry in a relative manner by normalizing the dose distribution towards an internal reference dose within the gel dosimeter phantom. 3D dosimetry with optical scanning has also been mostly applied in a relative way, although in principle absolute calibration is possible. As the optical absorption in 3D dosimeters is less dependent on temperature it can be expected that the achievable accuracy is higher with optical CT. The precision in optical scanning of 3D dosimeters depends to a large extend on the performance of the detector. 3D dosimetry with X-ray CT readout is a low contrast imaging modality for polymer gel dosimetry. Sources of error in x-ray CT polymer gel dosimetry (XCT) are currently under investigation and include inherent

  11. PET in cerebrovascular disease; PET bei zerebrovaskulaeren Erkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Herholz, K. [Neurologische Universitaetsklinik der Univ. Koeln (Germany)]|[Max-Planck-Institut fuer Neurologische Forschung, Koeln (Germany)

    1997-03-01

    Tissue viability is of particular interest in acute cerebral ischemia because it may be preserved if reperfusion can be achieved rapidly, e.g. by acute thrombolysis. Measurements of regional cerebral blood flow (CBF) and oxygen consumption by PET can assess tissue viability, and they have substantially increased our knowledge of th pathophysiology of ischemic stroke and the associated penumbra. Widerspread clinical application in acute stroke, however, is unlikely because of the large logistic and personnel resources required. In chronic cerebrovascular disease, measurement of regional CBF and glucose metabolism, which is usually coupled, provide detailed insights in disturbance of cortical function, e.g. due to deafferentiation, and contribute to differentiation of dementia types. Chronic misery perfusion, i.e. reduced perfusion that does not match the metabolic demand of the tissue, can be demonstrated by PET. It may be found in some patients with high-grade arterial stenoses. Less severe impairment of brain perfusion can be demonstrated by measurement of the cerebrovascular reserve capacity. The most frequent clinical situations can be assessed by less demanding procedures, e.g. by SPECT. In conclusion, PET has its role in cerebrovascular disease primarily within scientific studies, where high resolution and absolute quantitation of physiological variables are essential. (orig.). 65 refs. [Deutsch] Beim akuten ischaemischen Insult ist die Vitalitaet des Gewebes von besonderem Interesse, da sie durch rasche Reperfusion, z.B. durch Thrombolyse, erhalten bleiben kann. Messungen der zerebralen Durchblutung und des Sauerstoffumsatzes mittels PET geben darueber wesentliche Aufschluesse, und sie sind wichtig fuer das Verstaendnis der Pathophysiologie ischaemischer Infarkte und der Penumbra mit kritischer Perfusion beim Menschen. Ihre breitere Anwendung in der klinischen Patientenversorgung kommt allerdings wegen des hohen Aufwandes derzeit kaum in Betracht. Bei

  12. In aqua vivo EPID dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Wendling, Markus; McDermott, Leah N.; Mans, Anton; Olaciregui-Ruiz, Igor; Pecharroman-Gallego, Raul; Sonke, Jan-Jakob; Stroom, Joep; Herk, Marcel J.; Mijnheer, Ben van [Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Plesmanlaan 121, 1066 CX Amsterdam (Netherlands)

    2012-01-15

    Purpose: At the Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital in vivo dosimetry using an electronic portal imaging device (EPID) has been implemented for almost all high-energy photon treatments of cancer with curative intent. Lung cancer treatments were initially excluded, because the original back-projection dose-reconstruction algorithm uses water-based scatter-correction kernels and therefore does not account for tissue inhomogeneities accurately. The aim of this study was to test a new method, in aqua vivo EPID dosimetry, for fast dose verification of lung cancer irradiations during actual patient treatment. Methods: The key feature of our method is the dose reconstruction in the patient from EPID images, obtained during the actual treatment, whereby the images have been converted to a situation as if the patient consisted entirely of water; hence, the method is termed in aqua vivo. This is done by multiplying the measured in vivo EPID image with the ratio of two digitally reconstructed transmission images for the unit-density and inhomogeneous tissue situation. For dose verification, a comparison is made with the calculated dose distribution with the inhomogeneity correction switched off. IMRT treatment verification is performed for each beam in 2D using a 2D {gamma} evaluation, while for the verification of volumetric-modulated arc therapy (VMAT) treatments in 3D a 3D {gamma} evaluation is applied using the same parameters (3%, 3 mm). The method was tested using two inhomogeneous phantoms simulating a tumor in lung and measuring its sensitivity for patient positioning errors. Subsequently five IMRT and five VMAT clinical lung cancer treatments were investigated, using both the conventional back-projection algorithm and the in aqua vivo method. The verification results of the in aqua vivo method were statistically analyzed for 751 lung cancer patients treated with IMRT and 50 lung cancer patients treated with VMAT. Results: The improvements by

  13. Ambiguity resolution performance with GPS and BeiDou for LEO formation flying

    Science.gov (United States)

    Verhagen, Sandra; Teunissen, Peter J. G.

    2014-09-01

    The evolving BeiDou Navigation Satellite System constellation brings new opportunities for high-precision applications. In this contribution the focus will be on one such application, namely precise and instantaneous relative navigation of a formation of LEO satellites. The aim is to assess the ambiguity resolution performance with the future GPS and BeiDou constellations depending on system choice (GPS, BeiDou, or GPS+BeiDou), single- or dual-frequency observations, receiver noise, and uncertainties in ionosphere modelling. In addition, for the GPS+BeiDou constellation it will be shown how the growing BeiDou constellation in the years to come can already bring an important performance improvement compared to the GPS-only case. The performance will be assessed based on the percentage of time that the required precision can be obtained with a partial ambiguity resolution strategy.

  14. Technical Basis Document for PFP Area Monitoring Dosimetry Program

    CERN Document Server

    Cooper, J R

    2000-01-01

    This document describes the phantom dosimetry used for the PFP Area Monitoring program and establishes the basis for the Plutonium Finishing Plant's (PFP) area monitoring dosimetry program in accordance with the following requirements: Title 10, Code of Federal Regulations (CFR), part 835, ''Occupational Radiation Protection'' Part 835.403; Hanford Site Radiological Control Manual (HSRCM-1), Part 514; HNF-PRO-382, Area Dosimetry Program; and PNL-MA-842, Hanford External Dosimetry Technical Basis Manual.

  15. Dosimetry at a 400 keV accelerator

    DEFF Research Database (Denmark)

    Miller, A.

    1992-01-01

    Absolute calorimetric dosimetry and relative dose mapping methods are described for a 400 keV electron accelerator used for polymer curing and crosslinking experiments. These methods of dosimetry are also useful at accelerators used in gas cleaning processes.......Absolute calorimetric dosimetry and relative dose mapping methods are described for a 400 keV electron accelerator used for polymer curing and crosslinking experiments. These methods of dosimetry are also useful at accelerators used in gas cleaning processes....

  16. Personnel neutron dosimetry at Department of Energy facilities

    Energy Technology Data Exchange (ETDEWEB)

    Brackenbush, L.W.; Endres, G.W.R.; Selby, J.M.; Vallario, E.J.

    1980-08-01

    This study assesses the state of personnel neutron dosimetry at DOE facilities. A survey of the personnel dosimetry systems in use at major DOE facilities was conducted, a literature search was made to determine recent advances in neutron dosimetry, and several dosimetry experts were interviewed. It was concluded that personnel neutron dosimeters do not meet current needs and that serious problems exist now and will increase in the future if neutron quality factors are increased and/or dose limits are lowered.

  17. Kulturspezifische Elemente und ihre Problematik bei der Filmsynchronisierung

    Directory of Open Access Journals (Sweden)

    Prof. Dr. Carmen Cuéllar Lázaro

    2013-07-01

    Full Text Available Bei der Untersuchung der Übersetzungsproblematik von kulturspezifischen Elementen geht es darum, diese Konzepte begrifflich abzugrenzen, inhaltlich und sprachlich zu klassifizieren sowie die Problematik ihrer Übersetzung zu beschreiben. Bei der Filmsynchronisierung sind außerdem die Merkmale und besonderen Bedingungen des Mediums und des audiovisuellen Textes zu berücksichtigen. Die Zielsetzung dieser Studie ist, die Übersetzung von kulturspezifischen Elementen der Filmsynchronisierung (Deutsch-Spanisch zu analysieren. Wir schlagen ein Zwei-Ebenen-Modell vor: Die erste Ebene berücksichtigt die Art der erfahrenen sprachlichen Bearbeitung. Auf der zweiten Ebene wird die kulturelle Orientierung der Ergebnisse untersucht. Danach werden einige Schlussfolgerungen aus der spanischen Synchronfassung gezogen.

  18. Kulturspezifische Elemente und ihre Problematik bei der Filmsynchronisierung

    Directory of Open Access Journals (Sweden)

    Prof. Dr. Carmen Cuéllar Lázaro

    2013-07-01

    Full Text Available Bei der Untersuchung der Übersetzungsproblematik von kulturspezifischen Elementen geht es darum, diese Konzepte begrifflich abzugrenzen, inhaltlich und sprachlich zu klassifizieren sowie die Problematik ihrer Übersetzung zu beschreiben. Bei der Filmsynchronisierung sind außerdem die Merkmale und besonderen Bedingungen des Mediums und des audiovisuellen Textes zu berücksichtigen.   Die Zielsetzung dieser Studie ist, die Übersetzung von kulturspezifischen Elementen der Filmsynchronisierung (Deutsch-Spanisch zu analysieren. Wir schlagen ein Zwei-Ebenen-Modell vor: Die erste Ebene berücksichtigt die Art der erfahrenen sprachlichen Bearbeitung. Auf der zweiten Ebene wird die kulturelle Orientierung der Ergebnisse untersucht. Danach werden einige Schlussfolgerungen aus der spanischen Synchronfassung gezogen.

  19. Extraintestinale Manifestationen bei chronisch-entzündlichen Darmerkrankungen

    Directory of Open Access Journals (Sweden)

    Krones E

    2013-01-01

    Full Text Available Extraintestinale Manifestationen umfassen Krankheitsbilder, die außerhalb des Gastrointestinaltrakts bei Morbus Crohn und Colitis ulcerosa auftreten und eine gemeinsame Pathogenese vermuten lassen. Zu den häufigsten extraintestinalen Manifestationen zählen Gelenksbeschwerden sowie Hautmanifestationen, wie das Erythema nodosum oder das Pyoderma gangraenosum, Augenbeteiligungen im Sinne einer Episkleritis oder anterioren Uveitis und die primär sklerosierende Cholangitis. Diese Erkrankungen treten zum Teil schubassoziiert und zum Teil unabhängig von der Aktivität der begleitenden chronisch-entzündlichen Darmerkrankung (CED auf. Das therapeutische Management der schubassoziierten extraintestinalen Manifestationen besteht im Wesentlichen in der Therapie der CED. Neben extraintestinalen Manifestationen im engeren Sinn gilt es bei CED eine Vielzahl an extraintestinalen Komplikationen und assoziierten Autoimmunerkrankungen zu beachten.

  20. Therapie-Adhärenz bei arterieller Hypertonie

    Directory of Open Access Journals (Sweden)

    Gaul G

    2001-01-01

    Full Text Available Therapieadhärenz ist bei allen chronischen Erkrankungen mit einer über Jahre gehenden, oft lebenslangen Therapie ein zentrales Problem. Hypertonie ist eine Volkserkrankung, die bei einem Viertel der erwachsenen Bevölkerung auftritt. Aufgrund der Auswirkungen auf die Gefäße des gesamten arteriellen Schenkels des Kreislaufsystems und im speziellen auf das Gefäßsystem der Zielorgane Herz, Hirn und Niere ist die Hypertonie - besonders die insuffizient behandelte - eine Hauptursache für das hohe Ausmaß an tödlichen Herz-Kreislauferkrankungen. In der vorliegenden Übersicht wird der Begriff der Therapieadhärenz definiert und die Ursachen einer schlechten und guten Befolgung der therapeutischen Ratschläge diskutiert. Schließlich werden Empfehlungen zur Besserung der Therapieadhärenz aufgezeigt.

  1. Aussprachliche Interferenzen der Studenten bei der DaF-Lehrerausbildung

    Directory of Open Access Journals (Sweden)

    Ayhan BAYRAK

    2013-12-01

    Full Text Available Ziel dieser Untersuchung ist es, die Aussprachefehler der türkischen Studenten, die an der Anadolu Universität Deutsch als Fremdsprache studieren, zu bestimmen und näher auf die wirkenden Einflussfaktoren einzugehen. Dazu wurde von den StudentInnen verlangt, 15 deutsche Sätze und 20 deutsche Wörter vorzulesen, wobei Tonbandaufnahmen gemacht wurden. Danach wurde diese Tonbandaufnahmen analysiert. Im segmentalen Bereich haben sie Schwierigkeiten der kurzen und langen Vokale (% 38. Der zweithäufigste Fehler entstand beim Schwa-Laut [∂] (% 15,9. Bei den Konsonanten wurden folgende Abweichungen festgestellt; [Ik] statt [Iç] (% 8,4; Artikulation des [h] an medialer und finaler Stelle (% 7,3; [s] statt [z] (% 4,2; [z] statt [ts] (% 4,2. Im suprasegmentalen Bereich wurden die Abweichungen von Normen bei der Akzentuierung festgestellt (% 33, 1.

  2. Neurostimulation bei refraktärer Angina pectoris

    Directory of Open Access Journals (Sweden)

    Theres H

    2005-01-01

    Full Text Available Trotz großer Fortschritte der katheterinterventionellen und operativen Versorgung der koronaren Herzkrankheit (KHK verbleiben Patienten, bei denen eine Revaskularisierung nicht möglich ist. Besteht eine ausgeprägte Angina pectoris (CCS III–IV, so sprechen wir von einer "refraktären Angina pectoris". Eine Arbeitsgruppe der Europäischen Gesellschaft für Kardiologie führt die Neurostimulation an erster Stelle der alternativen Therapiemöglichkeiten für diese Patienten an. Zahlreiche Studien belegen, daß es sich dabei um eine effiziente und sichere adjuvante Therapie handelt. Sie führt zu einer Abnahme der Angina pectoris-Symptomatik mit konsekutiver Zunahme der körperlichen Leistungsfähigkeit. Ingesamt wird eine entscheidende Verbesserung der Lebensqualität erzielt, die Angina pectoris als Warnsymptom bei Myokardinfarkt wird jedoch nicht maskiert.

  3. Laktoseintoleranz bei Morbus Crohn und Colitis ulcerosa unter Berücksichtigung der ethnischen Herkunft

    OpenAIRE

    Demirci, Ilknur

    2007-01-01

    Die Frage der Inzidenz einer Laktosemalabsorption bei Morbus Crohn und Colitis ulcerosa wurde retrospektiv unter Berücksichtigung der ethnischen Herkunft untersucht. Bei 243 Patienten wurden zur Diagnose einer Laktosemalabsorption der Laktosetoleranztest und der H2-Atemtest durchgeführt. Dabei fand sich bei 23 (14,3%) von 161 Morbus Crohn Patienten eine Laktosemalabsorption. Nach ethnischer Differenzierung, zeigte sich in der mitteleuropäischen Population eine Häufigkeit von 13,2%...

  4. Mutationsanalyse im KCNAB1-Gen bei Rolando-Epilepsie

    OpenAIRE

    2012-01-01

    Epilepsien gehören zu den häufigsten neurologischen Erkrankungen. Ätiologisch unterscheidet man symptomatische Epilepsien, bei denen das Anfallsgeschehen Ausdruck einer Läsion oder Vorerkrankung des Zentralnervensystems ist, von den idiopathischen (genetischen) Epilepsien, denen eine polygene genetische Disposition zugrunde liegt. In exemplarischen Großfamilien konnten vielfach Defekte in Ionenkanalgenen gefunden werden. Die klinische Charakteristik epileptischer Anfälle und der elektroenzep...

  5. MRI in mucoviscidosis (cystic fibrosis); MRT bei Mukoviszidose

    Energy Technology Data Exchange (ETDEWEB)

    Eichinger, M.; Puderbach, M.; Kauczor, H.-U. [Deutsches Krebsforschungszentrum (DKFZ), Abteilung Radiologie, Heidelberg (Germany); Heussel, C.-P. [Universitaetsklinikum Mainz (Germany). Klinik und Poliklinik fuer Radiologie

    2006-04-15

    Cystic fibrosis (CF) is a multi-systemic disease with major impact on the lungs. Pulmonary manifestation is crucial for the prognosis and life expectancy of patients. Imaging modalities and lung function tests reflect the pulmonary status in these patients. The standard imaging modality for diagnosis and follow-up of pulmonary changes is chest x-ray. The gold standard for the detection of parenchymal lung changes remains high resolution computed tomography (HRCT), but this is not used routinely for CF-patients due to radiation exposure. Magnetic resonance imaging (MRI) used to be of no importance in monitoring cystic fibrosis lung disease, as shown in studies from the 1980s and early 1990s. The continuing improvement of MRI techniques, however, has allowed for an adequate application of this non-radiation method in diagnosing the major pulmonary findings in CF, in addition to the assessment of lung function. (orig.) [German] Die Lunge ist Hauptmanifestationsort der Mukoviszidose (zystischen Fibrose, CF) und entscheidend fuer Prognose und Lebenserwartung der Betroffenen. Bildgebende Verfahren spielen in der Diagnostik und Verlaufsbeurteilung der Lungenveraenderungen sowie dem Monitoring pulmonaler Komplikationen bei zystischer Fibrose eine wichtige Rolle. Obwohl die hochaufloesende Computertomographie (HRCT) als Goldstandard zur Beurteilung morphologischer Lungenveraenderungen bei zystischer Fibrose gilt, ist die Roentgenthoraxaufnahme aufgrund der geringeren Strahlenbelastung bei den meist jungen Patienten das derzeit eingesetzte Standardverfahren zur Diagnostik und Verlaufsbeurteilung. Die Magnetresonanztomographie (MRT) spielte bislang in der Diagnostik und Verlaufsbeobachtung der zystischen Fibrose keine Rolle, da Arbeiten aus den 80er und fruehen 90er Jahren keinen sinnvollen Beitrag der MRT zeigen konnten. Durch die kontinuierliche Verbesserung der Technik ist es seit neuestem erstmals moeglich, die MRT als Alternative fuer die Lungenbildgebung bei zystischer

  6. Sicherheitskriterien bei der Auswahl von ERP-Systemen

    OpenAIRE

    Wollersheim, Jan;Konstantinidis, Christos;Krcmar, Helmut

    2014-01-01

    Bei Auswahl und Anpassung von Software as a Service (SaaS) basierten ERP-Systemen (SaaS-ERP) kann auf bew?hrte und erprobte Kriterien zur?ckgegriffen werden. Dieser Beitrag strukturiert exemplarisch ausgew?hlte Sicherheits- und Risiko-Kriterien (S&R-Kriterien) anhand von f?nf Perspektiven. Dabei wird zuerst die Auswahl und im Folgenden die Anpassung von SaaS basierten ERP-Systemen betrachtet.

  7. Potenziale der Produktionsplanung und -steuerung bei IT-Dienstleistern

    OpenAIRE

    Ebert, Nico; Vogedes, Alexander; Hau, Thorsten; Uebernickel, Falk; Brenner, Walter

    2008-01-01

    Aufgrund von steigendem Kostendruck und zunehmender Kundenorientierung nutzen IT-Dienstleister bestehende Konzepte aus der Realgüterfertigung um sich zu professionalisieren. Im Rahmen des Artikels wird untersucht, welche Potenziale in der Übertragung von Ansätzen der Produktionsplanung und -steuerung in die Domäne der Produktion von IT-Dienstleistungen liegen. Dabei wird ein Fallbeispiel bei der Swisscom IT Services herangezogen, um einen ersten Lösungsansatz zu präsentieren.

  8. Ergebnisse der mikrobiologischen und histopathologischen Revisionsdiagnostik bei unklarem Endoprothesenversagen

    OpenAIRE

    Riemann, Johannes; Kienapfel, Heino

    2016-01-01

    Die Endoprothetik ist eine der erfolgreichsten operativen Behandlungs-methoden der modernen Medizin und bietet Patienten mit fortgeschrittener Arthrose eine etablierte Therapiemöglichkeit. In Deutschland gehört der künst-liche Gelenkersatz im Bereich des Hüft- und Kniegelenkes zu den häufigsten durchgeführten Operationen. Bei hohen Implantationszahlen und steigender Lebenserwartung kam es in den letzten Jahren auch zu einem Anstie...

  9. MR spectroscopy in dementia; MR-Spektroskopie bei Demenz

    Energy Technology Data Exchange (ETDEWEB)

    Hauser, T.; Gerigk, L.; Giesel, F.; Schuster, L.; Essig, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung E010, Radiologie, Heidelberg (Germany)

    2010-09-15

    With an increasingly aging population we are faced with the problem of an increasing number of dementia patients. In addition to clinical, neuropsychological and laboratory procedures, MRI plays an important role in the early diagnosis of dementia. In addition to various morphological changes functional changes can also help in the diagnosis and differential diagnosis of dementia. Overall the diagnosis of dementia can be improved by using parameters from MR spectroscopy. This article focuses on MR spectroscopic changes in the physiological aging process as well as on changes in mild cognitive impairment a precursor of Alzheimer's dementia, in Alzheimer's dementia, frontotemporal dementia, vascular dementia and Lewy body dementia. (orig.) [German] Angesichts einer immer aelter werdenden Bevoelkerung sind wir mit dem Problem einer zunehmenden Zahl an Demenzerkrankungen konfrontiert. Neben klinischen, neuropsychologischen und laborchemischen Verfahren spielt die MRT zur Fruehdiagnostik einer Demenz eine wichtige Rolle. Morphologische Veraenderungen wie auch verschiedene funktionelle Verfahren helfen bei der Diagnostik und Differenzialdiagnostik einer Demenz. Insgesamt kann mittels MR-spektroskopischer Parameter die Diagnostik einer Demenz verbessert werden. In diesem Artikel soll auf MR-spektroskopische Veraenderungen im Rahmen des physiologischen Alterungsprozesses eingegangen werden. Ferner werden speziell Veraenderungen bei leichter kognitiver Beeintraechtigung, einer Vorform der Alzheimer-Demenz, bei Alzheimer-, frontotemporaler, vaskulaerer und Lewy-Koerper-Demenz eroertert. (orig.)

  10. Advances in nuclear particle dosimetry for radiation protection and medicine - Ninth Symposium on Neutron Dosimetry (Editorial Material, English)

    Energy Technology Data Exchange (ETDEWEB)

    Zoetelief, J; Bos, A J.; Schuhmacher, H; McDonald, Joseph C.; Schultz, F W.; Pihet, P

    2004-12-15

    The Ninth Symposium on Neutron Dosimetry has been expanded to cover not only neutron radiation but heavy charged particle dosimetry as well. The applications are found in such fields as radiation protection, aircrew dosimetry, medicine, nuclear power and accelerator health physics. Scientists from many countries from around the world presented their work, and described the latest developments in techniques and instrumentation.

  11. Instrumentation for the individual dosimetry of workers

    CERN Document Server

    Thévenin, J C

    2003-01-01

    The control of the radiation dose exposure of workers and personnel exposed to ionizing radiations (nuclear industry, nuclear medicine, army, university laboratories etc..) is ensured by individual dosemeters. This dosimetry is mandatory for all workers susceptible to be exposed to more than 30% of the regulatory dose limit. dosemeters are worn on the chest and in some particular cases, on the finger (dosemeter rings) or on the wrist. Passive dosemeters allow to measure the dose a posteriori, while electronic dosemeters allow a direct reading and recording of the dose. This article presents successively: 1 - the general principles of individual dosimetry: situations of exposure, radiation detection, operational data, standardization, calibration and quality assurance, measurement uncertainties; 2 - goals and regulatory framework of individual dosimetry: regulation and recommendations, optimization, respect of dose limits, accidental situations; 3 - passive dosemeters: film, thermoluminescent, radio-photolumin...

  12. Model selection for radiochromic film dosimetry

    CERN Document Server

    Méndez, Ignasi

    2015-01-01

    The purpose of this study was to find the most accurate model for radiochromic film dosimetry by comparing different channel independent perturbation models. A model selection approach based on (algorithmic) information theory was followed, and the results were validated using gamma-index analysis on a set of benchmark test cases. Several questions were addressed: (a) whether incorporating the information of the non-irradiated film, by scanning prior to irradiation, improves the results; (b) whether lateral corrections are necessary when using multichannel models; (c) whether multichannel dosimetry produces better results than single-channel dosimetry; (d) which multichannel perturbation model provides more accurate film doses. It was found that scanning prior to irradiation and applying lateral corrections improved the accuracy of the results. For some perturbation models, increasing the number of color channels did not result in more accurate film doses. Employing Truncated Normal perturbations was found to...

  13. Performance testing of UK personal dosimetry laboratories

    CERN Document Server

    Marshall, T O

    1985-01-01

    The proposed Ionising Radiations Regulations will require all UK personal dosimetry laboratories that monitor classified personnel to be approved for personal dosimetry by the Health and Safety Executive. It is suggested that these approvals should be based on general and supplementary criteria published by the British Calibration Service (BCS) for laboratory approval for the provision of personal dosimetry services. These criteria specify certain qualitative requirements and also indicate the need for regular tests of performance to be carried out to ensure constancy of dosimetric standards. This report concerns the latter. The status of the BCS criteria is discussed and the need for additional documents to cover new techniques and some modifications to existing documents is indicated. A means is described by which the technical performance of laboratories, concerned with personal monitoring for external radiations, can be assessed, both initially and ongoing. The costs to establish the scheme and operate it...

  14. Bayesian Methods for Radiation Detection and Dosimetry

    CERN Document Server

    Groer, Peter G

    2002-01-01

    We performed work in three areas: radiation detection, external and internal radiation dosimetry. In radiation detection we developed Bayesian techniques to estimate the net activity of high and low activity radioactive samples. These techniques have the advantage that the remaining uncertainty about the net activity is described by probability densities. Graphs of the densities show the uncertainty in pictorial form. Figure 1 below demonstrates this point. We applied stochastic processes for a method to obtain Bayesian estimates of 222Rn-daughter products from observed counting rates. In external radiation dosimetry we studied and developed Bayesian methods to estimate radiation doses to an individual with radiation induced chromosome aberrations. We analyzed chromosome aberrations after exposure to gammas and neutrons and developed a method for dose-estimation after criticality accidents. The research in internal radiation dosimetry focused on parameter estimation for compartmental models from observed comp...

  15. Dosimetry procedures for an industrial irradiation plant

    Science.gov (United States)

    Grahn, Ch.

    Accurate and reliable dosimetry procedures constitute a very important part of process control and quality assurance at a radiation processing plant. γ-Dose measurements were made on the GBS 84 irradiator for food and other products on pallets or in containers. Chemical dosimeters wre exposed in the facility under conditions of the typical plant operation. The choice of the dosimeter systems employed was based on the experience in chemical dosimetry gained over several years. Dose uniformity information was obtained in air, spices, bulbs, feeds, cosmetics, plastics and surgical goods. Most products currently irradiated require dose uniformity which can be efficiently provided by pallet or box irradiators like GBS 84. The radiation performance characteristics and some dosimetry procedures are discussed.

  16. Protocol for emergency EPR dosimetry in fingernails.

    Science.gov (United States)

    Trompier, F; Kornak, L; Calas, C; Romanyukha, A; Leblanc, B; Mitchell, C A; Swartz, H M; Clairand, I

    2007-08-01

    There is an increased need for after-the-fact dosimetry because of the high risk of radiation exposures due to terrorism or accidents. In case of such an event, a method is needed to make measurements of dose in a large number of individuals rapidly and with sufficient accuracy to facilitate effective medical triage. Dosimetry based on EPR measurements of fingernails potentially could be an effective tool for this purpose. This paper presents the first operational protocols for EPR fingernail dosimetry, including guidelines for collection and storage of samples, parameters for EPR measurements, and the method of dose assessment. In a blinded test of this protocol application was carried out on nails freshly sampled and irradiated to 4 and 20 Gy; this protocol gave dose estimates with an error of less than 30%.

  17. Pulmonary manifestations in collagen vascular diseases; Pulmonale Manifestationen bei Kollagenosen

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, M.N.A. [Thoraxklinik, Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Translational Lung Research Center (TLRC), Heidelberg (Germany); Kreuter, M. [Thoraxklinik, Universitaetsklinikum Heidelberg, Zentrum fuer interstitielle und seltene Lungenerkrankungen, Pneumologie und Beatmungsmedizin, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Translational Lung Research Center (TLRC), Heidelberg (Germany); Kauczor, H.U. [Radiologische Klinik, Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Translational Lung Research Center (TLRC), Heidelberg (Germany); Heussel, C.P. [Thoraxklinik, Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie mit Nuklearmedizin, Heidelberg (Germany); Radiologische Klinik, Universitaetsklinikum Heidelberg, Abteilung fuer Diagnostische und Interventionelle Radiologie, Heidelberg (Germany); Universitaetsklinikum Heidelberg, Translational Lung Research Center (TLRC), Heidelberg (Germany)

    2016-10-15

    Pulmonary complications are frequent in patients with collagen vascular diseases (CVD). Frequent causes are a direct manifestation of the underlying disease, side effects of specific medications and lung infections. The standard radiological procedure for the work-up of pulmonary pathologies in patients with CVD is multidetector computed tomography (MDCT) with thin-slice high-resolution reconstruction. The accuracy of thin-slice CT for the identification of particular disease patterns is very high. The pattern of usual interstitial pneumonia (UIP) representing the direct pulmonary manifestation of rheumatoid arthritis (RA) can be identified with a sensitivity of 45 % and a specificity of 96 %. Both direct pulmonary manifestations, drug-induced toxicity and certain infections can have a similar appearance in thin-slice MDCT in various forms of CVD. Knowledge of the patterns and causes contributes to the diagnostic certainty. At first diagnosis of a CVD and associated pulmonary symptoms thin-slice MDCT is recommended. Clinical, lung function and imaging follow-up examinations should be performed every 6-12 months depending on the results of the MDCT. In every case the individual CT morphological patterns of pulmonary involvement must be identified. The combination of information on the anamnesis, clinical and imaging results is a prerequisite for an appropriate disease management. (orig.) [German] Pulmonale Komplikationen sind bei Patienten mit Kollagenosen keine Seltenheit. Haeufig sind eine direkte Manifestation der Grunderkrankung, eine Nebenwirkung der medikamentoesen Therapie oder eine Lungeninfektion die Ursachen. Das radiologische Standardverfahren zur Klaerung pulmonaler Pathologien bei Patienten mit Kollagenosen ist die Multidetektorcomputertomographie mit duennschichtigen Rekonstruktionen (Duennschicht-MDCT). Die Treffsicherheit der Duennschicht-MDCT ist fuer die Identifikation eines Erkrankungsmusters sehr hoch. So kann beispielsweise das Muster einer

  18. UMA PROSPOSTA DEDUTIVISTA PARA PRINCÍPIOS CONTÁBEIS

    Directory of Open Access Journals (Sweden)

    Paulo Schmidt

    2009-09-01

    Full Text Available A proposta deste estudo a apresentar um breve relato sobre a evolução do pensamento cientifico ocorrida na física com a substituição dos princípios contábeis e filosófico, desde a Antiguidade grega ate os dias de hoje, como forma de fundamentar o posicionamento contrario ao raciocínio indutivo para o estabelecimento de uma estrutura conceitual para a contabilidade e para o desenvolvimento dos princípios contábeis. Apos essa incursão pelo campo filosófico, será aduzido um dos trabalhos de D. R. Scott, ex-professor da Universidade de Michigan, que já na década de 1930 defendia o processo de raciocínio dedutivo e a necessidade de coerência e unidade para o estabelecimento dos princípios contábeis. Este estudo justifica-se, principalmente, porque ainda existem pesquisadores da área contábil que defendem o método indutivo com único procedimento cientifico capaz de levar a certeza, Como defendia Descartes. Alem disso, mesmo apos a revolução cientifica princípios teóricos de Newton, pelos princípios da teoria da relatividade de Einstein, alguns pesquisadores defendem a imutabilidade dos princípios contábeis, como sendo verdades indubitáveis, não aceitando o permanente desenvolvimento da teoria contábil e sua continua adaptabilidade a nova realidade ambiental. A contabilidade, assim como toda disciplina do conhecimento humano que postula um patamar cientifico, deve estruturar-se com base em um conjunto de princípios racionalmente dispostos. Diante desse panorama, faz-se mister inquirir se os princípios contábeis podem ser oniscientes e impassíveis as mudanças do mundo?

  19. Reactor Dosimetry State of the Art 2008

    Science.gov (United States)

    Voorbraak, Wim; Debarberis, Luigi; D'Hondt, Pierre; Wagemans, Jan

    2009-08-01

    Oral session 1: Retrospective dosimetry. Retrospective dosimetry of VVER 440 reactor pressure vessel at the 3rd unit of Dukovany NPP / M. Marek ... [et al.]. Retrospective dosimetry study at the RPV of NPP Greifswald unit 1 / J. Konheiser ... [et al.]. Test of prototype detector for retrospective neutron dosimetry of reactor internals and vessel / K. Hayashi ... [et al.]. Neutron doses to the concrete vessel and tendons of a magnox reactor using retrospective dosimetry / D. A. Allen ... [et al.]. A retrospective dosimetry feasibility study for Atucha I / J. Wagemans ... [et al.]. Retrospective reactor dosimetry with zirconium alloy samples in a PWR / L. R. Greenwood and J. P. Foster -- Oral session 2: Experimental techniques. Characterizing the Time-dependent components of reactor n/y environments / P. J. Griffin, S. M. Luker and A. J. Suo-Anttila. Measurements of the recoil-ion response of silicon carbide detectors to fast neutrons / F. H. Ruddy, J. G. Seidel and F. Franceschini. Measurement of the neutron spectrum of the HB-4 cold source at the high flux isotope reactor at Oak Ridge National Laboratory / J. L. Robertson and E. B. Iverson. Feasibility of cavity ring-down laser spectroscopy for dose rate monitoring on nuclear reactor / H. Tomita ... [et al.]. Measuring transistor damage factors in a non-stable defect environment / D. B. King ... [et al.]. Neutron-detection based monitoring of void effects in boiling water reactors / J. Loberg ... [et al.] -- Poster session 1: Power reactor surveillance, retrospective dosimetry, benchmarks and inter-comparisons, adjustment methods, experimental techniques, transport calculations. Improved diagnostics for analysis of a reactor pulse radiation environment / S. M. Luker ... [et al.]. Simulation of the response of silicon carbide fast neutron detectors / F. Franceschini, F. H. Ruddy and B. Petrović. NSV A-3: a computer code for least-squares adjustment of neutron spectra and measured dosimeter responses / J. G

  20. Beta-radiation exposure at the finger tips during the radionuclide synovectomy; Beta-Ortsdosimetrie der Fingerkuppen bei der Radiosynoviorthese

    Energy Technology Data Exchange (ETDEWEB)

    Liepe, K.; Andreeff, M.; Wunderlich, G.; Kropp, J.; Kotzerke, J. [Klinik und Poliklinik fuer Nuklearmedizin, TU Dresden (Germany); Mielcarek, J.; Barth, I. [Bundesamt fuer Strahlenschutz (Germany)

    2003-06-01

    Aim: The radiation synovectomy is a widespread therapeutic option in rheumatoid arthritis. However, data for the {beta}-radiation exposure are rare. The aim of this study was to determine the personal dose equivalent H{sub p}(0.07) of the skin of the hands. Methods: Thermoluminescence detectors (TLDs) were attached at all fingertips of the therapist, the radiochemist and the nurse. In summary, the measurement of {beta}-exposure occurred in 155 joints at 6 days with different radionuclides ({sup 169}Er, {sup 186}Re, {sup 90}Y). Results: The greatest beta exposure were show at the forefinger (L-Ff) and thumb (L-Th) of the left hand, with which the therapist (right hander) fixed the injection needle. In 52 treated finger-joints (1204 MBq {sup 169}Er), 29 treated large joints (2405 MBq {sup 186}Re) and 15 treated knees (3100 MBq {sup 90}Y) we found a cumulative beta exposure over all radionuclides of 190 mSv at L-Ff and 48 mSv at L-Th. The specific beta exposure for the individual radionuclides showed beta exposures of 0,56 {mu}Sv/MBq for {sup 169}Er and 1,52 {mu}Sv/MBq for {sup 186}Re-186 at the L-Ff. With using a manipulator the {beta}-exposure ({sup 90}Y) could reduced from 22,09 to 0,42 {mu}Sv/MBq at the L-Ff. The greatest beta exposures for the radiochemist was 119 mSv at the L-Ff for all radionuclides. Conclusion: In usual techniques of radiation synovectomy the {sup 90}Y produced the greatest part of radiation exposure. Especially at the L-Ff it might exceed the German limit for the official dosimetry service at the skin (paragraph 55 Strl-SchV). Using a holding forceps we can keep the legal rules and can reduce considerably the beta exposure. (orig.) [German] Ziel: Der Anstieg der Therapiezahlen bei der Radiosynoviorthese (RSO) und die neue Strahlenschutzverordnung (StrSchV) erfordern, die {beta}-Strahlenbelastung, H{sub p}(0,07), des Personals bei der RSO zu dokumentieren. Methode: Da die amtlichen Teilkoerperdosimeter (TLD-Fingerringdosimeter) die {beta

  1. Dosimetry of Low-Energy Beta Radiation

    DEFF Research Database (Denmark)

    Borg, Jette

    Useful techniques and procedures for derermination of absorbed doses from exposure in a low-energy beta radiation were studied and evaluated. The four techniques included were beta spectrometry, extrapolation chamber dosimetry, Monte Carlo (MC) calculations, and exoelectron dosimetry. As a typical...... low-energy beta radiation field a moderated spectrum from a carbon-14 source was used. The measured responce of a Si(Li) detector to photons (bremsstrahlung) showed fine agreemant with the MC calculated photon response, whereas the difference between measured and MC calculated response to electrons...

  2. Technical basis for internal dosimetry at Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

    1991-07-01

    The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products ({sup 58}Co, {sup 60}Co, {sup 54}Mn, and {sup 59}Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium,. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation and bioassay follow-up treatment. 78 refs., 35 figs., 115 tabs.

  3. Technical basis for internal dosimetry at Hanford

    Energy Technology Data Exchange (ETDEWEB)

    Sula, M.J.; Carbaugh, E.H.; Bihl, D.E.

    1989-04-01

    The Hanford Internal Dosimetry Program, administered by Pacific Northwest Laboratory for the US Department of Energy, provides routine bioassay monitoring for employees who are potentially exposed to radionuclides in the workplace. This report presents the technical basis for routine bioassay monitoring and the assessment of internal dose at Hanford. The radionuclides of concern include tritium, corrosion products (/sup 58/Co, /sup 60/Co, /sup 54/Mn, and /sup 59/Fe), strontium, cesium, iodine, europium, uranium, plutonium, and americium. Sections on each of these radionuclides discuss the sources and characteristics; dosimetry; bioassay measurements and monitoring; dose measurement, assessment, and mitigation; and bioassay follow-up treatment. 64 refs., 42 figs., 118 tabs.

  4. Optically stimulated luminescence in retrospective dosimetry

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Murray, A.S.

    2002-01-01

    Since the beginning of the 1990s the exploration of optically stimulated luminescence (OSL) in retrospective accident dosimetry has driven an intensive investigation and development programme at Riso into measurement facilities and techniques. This paper reviews some of the outcomes of this progr......Since the beginning of the 1990s the exploration of optically stimulated luminescence (OSL) in retrospective accident dosimetry has driven an intensive investigation and development programme at Riso into measurement facilities and techniques. This paper reviews some of the outcomes...

  5. SNL RML recommended dosimetry cross section compendium

    Energy Technology Data Exchange (ETDEWEB)

    Griffin, P.J.; Kelly, J.G.; Luera, T.F. [Sandia National Labs., Albuquerque, NM (United States); VanDenburg, J. [Science and Engineering Associates, Inc., Albuquerque, NM (United States)

    1993-11-01

    A compendium of dosimetry cross sections is presented for use in the characterization of fission reactor spectrum and fluence. The contents of this cross section library are based upon the ENDF/B-VI and IRDF-90 cross section libraries and are recommended as a replacement for the DOSCROS84 multigroup library that is widely used by the dosimetry community. Documentation is provided on the rationale for the choice of the cross sections selected for inclusion in this library and on the uncertainty and variation in cross sections presented by state-of-the-art evaluations.

  6. Dosimetry of Low-Energy Beta Radiation

    DEFF Research Database (Denmark)

    Borg, Jette

    Useful techniques and procedures for derermination of absorbed doses from exposure in a low-energy beta radiation were studied and evaluated. The four techniques included were beta spectrometry, extrapolation chamber dosimetry, Monte Carlo (MC) calculations, and exoelectron dosimetry. As a typical...... low-energy beta radiation field a moderated spectrum from a carbon-14 source was used. The measured responce of a Si(Li) detector to photons (bremsstrahlung) showed fine agreemant with the MC calculated photon response, whereas the difference between measured and MC calculated response to electrons...

  7. Framework for radiation pneumonitis risk stratification based on anatomic and perfused lung dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Dhami, Gurleen; Zeng, Jing; Patel, Shilpen A.; Rengan, Ramesh [University of Washington School of Medicine, Department of Radiation Oncology, Seattle, WA (United States); Vesselle, Hubert J.; Kinahan, Paul E.; Miyaoka, Robert S. [University of Washington School of Medicine, Department of Radiology, Seattle, WA (United States); Bowen, Stephen R. [University of Washington School of Medicine, Department of Radiation Oncology, Seattle, WA (United States); University of Washington School of Medicine, Department of Radiology, Seattle, WA (United States)

    2017-05-15

    To design and apply a framework for predicting symptomatic radiation pneumonitis in patients undergoing thoracic radiation, using both pretreatment anatomic and perfused lung dose-volume parameters. Radiation treatment planning CT scans were coregistered with pretreatment [{sup 99m}Tc]MAA perfusion SPECT/CT scans of 20 patients who underwent definitive thoracic radiation. Clinical radiation pneumonitis was defined as grade ≥ 2 (CTCAE v4 grading system). Anatomic lung dose-volume parameters were collected from the treatment planning scans. Perfusion dose-volume parameters were calculated from pretreatment SPECT/CT scans. Equivalent doses in 2 Gy per fraction were calculated in the lung to account for differences in treatment regimens and spatial variations in lung dose (EQD2{sub lung}). Anatomic lung dosimetric parameters (MLD) and functional lung dosimetric parameters (pMLD{sub 70%}) were identified as candidate predictors of grade ≥ 2 radiation pneumonitis (AUC > 0.93, p < 0.01). Pairing of an anatomic and functional dosimetric parameter (e.g., MLD and pMLD{sub 70%}) may further improve prediction accuracy. Not all individuals with high anatomic lung dose (MLD > 13.6 GyEQD2{sub lung}, 19.3 Gy for patients receiving 60 Gy in 30 fractions) developed radiation pneumonitis, but all individuals who also had high mean dose to perfused lung (pMLD{sub 70%} > 13.3 GyEQD2) developed radiation pneumonitis. The preliminary application of this framework revealed differences between anatomic and perfused lung dosimetry in this limited patient cohort. The addition of perfused lung parameters may help risk stratify patients for radiation pneumonitis, especially in treatment plans with high anatomic mean lung dose. Further investigations are warranted. (orig.) [German] Erstellung und Anwendung eines Rahmenwerks zur Vorhersage symptomatischer Strahlenpneumonitis bei Patienten mit einer Thorax-Bestrahlung anhand anatomischer und perfundierter Lungendosis-Volumen-Parameter in der

  8. Thermoluminescent dosimetry in computed tomography

    Energy Technology Data Exchange (ETDEWEB)

    Lara C, A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Unidad Legaria, Av. Legaria 694, Col. Irrigacion, 11500 Ciudad de Mexico (Mexico); Osorio V, M. [ISSSTE, Centro Medico Nacional 20 de Noviembre, Felix Cuevas 540, Col. del Valle, 03100 Ciudad de Mexico (Mexico); Hernandez O, O., E-mail: armando_lara_cam@yahoo.com.mx [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Ciudad de Mexico (Mexico)

    2016-10-15

    In this work we studied the dosimetry performed on CT scan in two different equipment, SOMATOM and Phillips, with 16 and 64 slice respectively. We used 51 pellets of lithium fluoride doped with magnesium and titanium (LiF: Mg, Ti) also knows as TLD-100 due to its physical properties and its easy of use, in this study, first analysis a batch of 56 pellets, but only 53 pellets were optimal for this study, cesium-137 was used as source irradiation, then proceeded to calibrate the batch with X-rays source, measuring the corresponding dose in a Farmers ionization chamber, then, we obtained a calibration curve, and we used as reference to calculation of the applied dose, finally designing ergonomic mesh, were it was deposited a TLD 100, placed in a regions of interest were made to each scan type. Once characterized our material proceeded to testing in 30 patients, which were irradiated with X-ray tube, whose operation was performed at 80, 120 kV with a current of 100, 300 and 400 m A according to scanning protocol. Overall we measured dose of 5 mGy to 53 mGy, these measurements reflect significant dose to can induced cancer, due previous reports published, that doses greater than 20 mGy there is a risk of developing cancer in the long term, but in practice when it assigned a medical diagnosis, there are no dose limits due to benefits patients, however, IAEA publish recommendations that allow us to carry out optimum handling of ionizing radiation, among these is the quality control of the tomography equipment that helps greatly reduce patient dose. (Author)

  9. Kinetics model for lutate dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Lima, M.F.; Mesquita, C.H., E-mail: mflima@ipen.br, E-mail: chmesqui@ipen.br [Instituto de Pesquisas Energeticas (IPEN/CNEN-SP), Sao Paulo, SP (Brazil)

    2013-11-01

    The use of compartmental analysis to predict the behavior of drugs in the organism is considered the better option among numerous methods employed in pharmacodynamics. A six compartments model was developed to determinate the kinetic constants of 177Lu-DOTATATO biodistribution using data from one published study with 67 patients treated by PRRT (Peptide receptor radionuclide therapy) and followed by CT during 68,25 hours. The compartmental analysis was made using the software AnaComp Registered-Sign . The influence of the time pos-injection over the dose assessment was studied taking into account the renal excretion management by aminoacid coinfusion, whose direct effects persist in the first day. The biodistribution curve was split in five sectors: 0-0.25h; 0-3.25h; 3.25-24.25h; 24.25-68.25h and 3.25-68.25h. After the examination of that influence, the study was concentrated in separate the biodistribution curve in two phases. Phase 1: governed by uptake from the blood, considering the time pos-injection until 3.25h and phase 2: governed by renal excretion, considering the time pos-injection from 3.25h to 68.25h. The model considered the organs and tissues superposition in the CT image acquisition by sampling parameters as the contribution of the the activity concentration in blood and relation between the sizes of the whole body and measured organs. The kinetic constants obtained from each phase (1 and 2) were used in dose assessment to patients in 26 organs and tissues described by MIRD. Dosimetry results were in agreement with the available results from literature, restrict to whole body, kidneys, bone marrow, spleen and liver. The advantage of the proposed model is the compartmental method quickness and power to estimate dose in organs and tissues, including tumor that, in the most part, were not discriminate by voxels of phantoms built using CT images. (author)

  10. A Method for Estimating BeiDou Inter-frequency Satellite Clock Bias

    Directory of Open Access Journals (Sweden)

    LI Haojun

    2016-02-01

    Full Text Available A new method for estimating the BeiDou inter-frequency satellite clock bias is proposed, considering the shortage of the current methods. The constant and variable parts of the inter-frequency satellite clock bias are considered in the new method. The data from 10 observation stations are processed to validate the new method. The characterizations of the BeiDou inter-frequency satellite clock bias are also analyzed using the computed results. The results of the BeiDou inter-frequency satellite clock bias indicate that it is stable in the short term. The estimated BeiDou inter-frequency satellite clock bias results are molded. The model results show that the 10 parameters of model for each satellite can express the BeiDou inter-frequency satellite clock bias well and the accuracy reaches cm level. When the model parameters of the first day are used to compute the BeiDou inter-frequency satellite clock bias of the second day, the accuracy also reaches cm level. Based on the stability and modeling, a strategy for the BeiDou satellite clock service is presented to provide the reference of our BeiDou.

  11. Abducensparese bei metastasiertem Prostatakarzinom: kleinvolumige Bestrahlung der Schädelbasis

    Directory of Open Access Journals (Sweden)

    Mayer R

    2001-01-01

    Full Text Available Wir berichten über drei Patienten mit Prostatakarzinom, bei denen eine Metastase im Bereich der Schädelbasis zu einer Abducensparese geführt hatte. Die Patienten klagten über Doppelbilder, die sie bei Verrichtungen des täglichen Lebens behinderten und zu Schwindel beim Gehen bis hin zur Übelkeit führten. Die Bestrahlung mit hochenergetischen Photonen (23 MeV und einer Dosis von 40-50 Gy/2 Gy erfolgte bei zwei Patienten über opponierende Gegenfelder und bei einem Patienten in Drei-Feld-Technik. Zwei Patienten waren bereits vorher wegen eines Adenokarzinoms der Prostata perkutan lokal im Beckenbereich bestrahlt worden, bei einem Patienten stellte die Abducensparese das Erstsymptom dar und das Prostatakarzinom wurde erst im Laufe der weiteren Exploration diagnostiziert. Durch die Bestrahlung der Schädelbasismetastase konnte bei allen drei Patienten ein guter palliativer Effekt erreicht werden, der bis zu ihrem Ableben anhielt. Bei einem Patienten kam es zu einem vollständigen Verschwinden der Doppelbilder, obwohl die Tumorausdehnung bei der Kontrolluntersuchung unverändert war; die beiden anderen Patienten gaben eine deutliche Besserung der Beschwerden und damit verbundene Hebung der Lebensqualität an. Zusammenfassend ist zu sagen, daß durch den Einsatz moderner Planungs- und Bestrahlungsmethoden die externe Strahlentherapie im Bereich der Schädelbasis nebenwirkungsarm und effizient durchgeführt werden kann.

  12. "Updates to Model Algorithms & Inputs for the Biogenic Emissions Inventory System (BEIS) Model"

    Science.gov (United States)

    We have developed new canopy emission algorithms and land use data for BEIS. Simulations with BEIS v3.4 and these updates in CMAQ v5.0.2 are compared these changes to the Model of Emissions of Gases and Aerosols from Nature (MEGAN) and evaluated the simulations against observatio...

  13. In vivo dosimetry in intraoperative electron radiotherapy. microMOSFETs, radiochromic films and a general-purpose linac

    Energy Technology Data Exchange (ETDEWEB)

    Lopez-Tarjuelo, Juan; Marco-Blancas, Noelia de; Santos-Serra, Agustin; Quiros-Higueras, Juan David [Consorcio Hospitalario Provincial de Castellon, Servicio de Radiofisica y Proteccion Radiologica, Castellon de la Plana (Spain); Bouche-Babiloni, Ana; Morillo-Macias, Virginia; Ferrer-Albiach, Carlos [Consorcio Hospitalario Provincial de Castellon, Servicio de Oncologia Radioterapica, Castellon de la Plana (Spain)

    2014-11-15

    Gebrauch von MOSFETs und Radiochromfilmen bei den Patienten, die sich einer IOERT-Behandlung mit einem Allzweck-Linac unterzogen. Es wurden in sterile Bronchialkatheter eingefuehrte MOSFETs sowie zerschnittene und digitalisierte Radiochromfilme, die durch Gasplasma sterilisiert wurden, verwendet. Insgesamt wurden 59 Messungen bei 27 Patienten durchgefuehrt. Dazu zaehlten 15 Primaertumore (7 Brust- und 8 anderweitige Tumore) und 12 erneut aufgetretene Tumore. Die Daten wurden einer Analyse mit atypischen Werten unterzogen und entsprechend ihrer Kompatibilitaet mit den relevanten Dosen klassifiziert. Gesucht wurden Assoziationen bezueglich der Art des Detektors, Brust- und Nichtbrustbestrahlung und der Bewertung durch den Radioonkologen hinsichtlich des Schwierigkeitsgrads der Detektorplatzierung. Ausserdem wurden 19 Messungen im Tumorbett mit beiden Detektoren durchgefuehrt. Es ergaben sich keine bedeutenden Unterschiede bei den Messergebnissen mit MOSFET (D = 93,5 %, s{sub D} = 6,5 %) und den Messergebnissen mit Radiochromfilmen (D = 96,0 %, s{sub D} = 5,5 %; p = 0,109). Assoziationen wurden nicht gefunden (p = 0,526; p = 0,295; p = 0,501). Auch die im Tumorbett durchgefuehrten Messungen mit den beiden Detektoren ergaben, dass die Messergebnisse mit MOSFET (D = 95,0 %, s{sub D} = 5,4 %) nicht wesentlich von den Messergebnissen mit Radiochromfilmen abwichen (D = 96,4 %, s{sub D} = 5,0 %; p = 0,363). Die In-vivo-Dosimetrie mit einem Allzweck-Linac kann an jeder untersuchten Stelle zu zufriedenstellenden Ergebnissen fuehren. Ausschlaggebend fuer die Wahl des Detektors sollten Benutzerfaktoren und nicht das Verhalten des Detektors selbst sein. Die Zusammenarbeit mit dem chirurgischen Team ist entscheidend fuer den Erfolg. (orig.)

  14. Dosimetry implant for treating restenosis and hyperplasia

    Science.gov (United States)

    Srivastava, Suresh; Gonzales, Gilbert R; Howell, Roger W; Bolch, Wesley E; Adzic, Radoslav

    2014-09-16

    The present invention discloses a method of selectively providing radiation dosimetry to a subject in need of such treatment. The radiation is applied by an implant comprising a body member and .sup.117mSn electroplated at selected locations of the body member, emitting conversion electrons absorbed immediately adjacent selected locations while not affecting surrounding tissue outside of the immediately adjacent area.

  15. Optically stimulated luminescence techniques in retrospective dosimetry

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; Murray, A.S.

    2001-01-01

    Optically stimulated luminescence signals from natural quartz and feldspar are now used routinely in dating geological and archaeological materials. More recently they have also been employed in accident dosimetry, i.e. the retrospective assessment of doses received as a result of a nuclear...

  16. Development of A-bomb survivor dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Kerr, G.D.

    1995-12-31

    An all important datum in risk assessment is the radiation dose to individual survivors of the bombings in Hiroshima and Nagasaki. The first set of dose estimates for survivors was based on a dosimetry system developed in 1957 by the Oak Ridge National Laboratory (ORNL). These Tentative 1957 Doses (T57D) were later replaced by a more extensive and refined set of Tentative 1965 Doses (T65D). The T65D system of dose estimation for survivors was also developed at ORNL and served as a basis for risk assessment throughout the 1970s. In the late 1970s, it was suggested that there were serious inadequacies with the T65D system, and these inadequacies were the topic of discussion at two symposia held in 1981. In early 1983, joint US- Japan research programs were established to conduct a thorough review of all aspects of the radiation dosimetry for the Hiroshima and Nagasaki A-bomb survivors. A number of important contributions to this review were made by ORNL staff members. The review was completed in 1986 and a new Dosimetry System 1986 (DS86) was adopted for use. This paper discusses the development of the various systems of A-bomb survivor dosimetry, and the status of the current DS86 system as it is being applied in the medical follow-up studies of the A-bomb survivors and their offspring.

  17. Computational Techniques of Electromagnetic Dosimetry for Humans

    Science.gov (United States)

    Hirata, Akimasa; Fujiwara, Osamu

    There has been increasing public concern about the adverse health effects of human exposure to electromagnetic fields. This paper reviews the rationale of international safety guidelines for human protection against electromagnetic fields. Then, this paper also presents computational techniques to conduct dosimetry in anatomically-based human body models. Computational examples and remaining problems are also described briefly.

  18. Thermoluminescence Dosimetry Applied to Radiation Protection

    DEFF Research Database (Denmark)

    Christensen, Poul; Bøtter-Jensen, Lars; Majborn, Benny

    1982-01-01

    This is a general review of the present state of the development and application of thermoluminescence dosimetry (TLD) for radiation protection purposes. A description is given of commonly used thermoluminescent dosimeters and their main dosimetric properties, e.g. energy response, dose range...

  19. Dosimetry implant for treating restenosis and hyperplasia

    Energy Technology Data Exchange (ETDEWEB)

    Srivastava, Suresh; Gonzales, Gilbert R; Howell, Roger W; Bolch, Wesley E; Adzic, Radoslav

    2014-09-16

    The present invention discloses a method of selectively providing radiation dosimetry to a subject in need of such treatment. The radiation is applied by an implant comprising a body member and .sup.117mSn electroplated at selected locations of the body member, emitting conversion electrons absorbed immediately adjacent selected locations while not affecting surrounding tissue outside of the immediately adjacent area.

  20. Intra-Operative Dosimetry in Prostate Brachytherapy

    Science.gov (United States)

    2007-11-01

    CT-based post-implant dosimetry. Figure 1: System concept for TRUS and C-arm fusion B BODY B.1 Brief System Concept The system concept for...C-arm calibration - is it really necessary?,” MICCAI, pp. 639–646, 2005. 10. Brainlab, Inc., Heimstetten, Germany, Vector Vision. 11. Medtronic

  1. Advances in reference and transfer dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Desrosiers, M.F. [Ionizing Radiation Division, Physics Laboratory, National Institute of Standards and Technology, Gaithersburg, Maryland 20899 (United States)

    1999-07-01

    All prerequisites are now in place to create a fundamentally and radically different type of calibration service for the radiation processing industry. Advancements in dosimetry and information technology can be combined to provide industry with on-line calibrations, on demand at a low cost. The remote calibration service will serve as a basis for other areas of metrology. (Author)

  2. Personnel radiation dosimetry symposium: program and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    1984-10-01

    The purpose was to provide applied and research dosimetrists with sufficient information to evaluate the status and direction of their programs relative to the latest guidelines and techniques. A technical program was presented concerning experience, requirements, and advances in gamma, beta, and neutron personnel dosimetry.

  3. MRCP in primary sclerosing cholangitis; MRCP bei primaerer sklerosierender Cholangitis

    Energy Technology Data Exchange (ETDEWEB)

    Weber, C.; Krupski, G.; Lorenzen, J.; Adam, G. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik und Poliklinik fuer Diagnostische und Interventionelle Radiologie; Grotelueschen, R.; Rogiers, X. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Abt. fuer Hepatobilaere Chirurgie; Seitz, U. [Universitaetsklinikum Hamburg-Eppendorf (Germany). Klinik fuer Interdisziplinaere Endoskopie

    2003-02-01

    Purpose: Evaluation of MR-cholangiopancreaticography (MRCP) for the diagnosis of primary sclerosing cholangitis (PSC) in correlation with endoscopic retrograde cholangiopancreaticography (ERCP) and in comparison to the diagnostic accuracy of various T2-weighted sequences. Methods and Materials: Fifty-five patients (34 males, 21 females: mean age 40 years, range 16 to 65 years) with suspected PSC were examined in a 1.5 T MR unit (Magnetom Vision, Siemens, Erlangen), using breath-hold transverse and coronal HASTE, paracoronal RARE and thin-sliced HASTE (TS-HASTE) sequences. Applying a five-point-scale, two blinded investigators assessed the image quality for ROC analysis. Morphologic criteria of PSC were documented and correlated with ERCP, which served as the gold standard, and sensitivity, specificity and diagnostic accuracy were calculated. Results: PSC was confirmed in 40 of 55 patients (ERCP 55 of 55, liver biopsy 37 of 55), with concomitant chronic ulcerative colitis in 27 and Crohn's disease in 6 of the 40 patients. Qualitative analysis of the image quality showed no significant difference between RARE, HASTE and thin-sliced HASTE sequences (3.4/3.5/3.2). The RARE sequence had the highest sensitivity (97%), specificity (64%) and accuracy (84%) for the detection of PSC. The difference between HASTE and thin-sliced HASTE was statistically significant (p<0.01). Of the 40 patients with confirmed PSC, 29 were followed by MRI and 3 underwent a liver transplantation within the follow-up period. A Klatskin tumor, which was misdiagnosed by MRCP, was diagnosed by brush biopsy in 1 of the 40 patients. Interobserver variability was adequate to good (kappa 0.4 to 0.7), depending on the chosen sequence. (orig.) [German] Ziel: Wertigkeit der MRCP bei der Diagnostik der primaeren sklerosierenden Cholangitis (PSC) in Korrelation zur endoskopischen retrograden Cholangiopankreatikographie (ERCP) und Vergleich der diagnostischen Treffsicherheit verschiedener T{sub 2

  4. Magnetic resonance tomography in eclampsia; Magetresonanztomographie bei Eklampsie

    Energy Technology Data Exchange (ETDEWEB)

    Uhlig, U. [St.-Vincentius-Krankenhaeuser, Karlsruhe (Germany). Radiologische Klinik

    1995-05-01

    Eclampsia is a rare but severe complication during the course of a pregnancy. The CT-findings at the brain are well known. Reports on MRT-findings are limited, however, especially in German literature. We describe the MRT picture of the cerebral changes caused by eclampsia and discuss the advantages of MRT in comparison with CT. The use of contrast agents with MRT shows breakdown of blood-brain barrier but does not provide any information of therapeutical consequences and should be avoided during pregnancy. An early and targeted use of MRT in any case of unclear or suspicious neurological symptoms during pregnancy is recommended. MRT supports differential diagnosis regarding non pregnancy-related cerebral disease and can be helpful for therapy planning in cases of preeclampsia. Additionally, MRT offers the possibility to control the effect of therapy with regard to brain damage. (orig.) [Deutsch] Die Eklampsie ist eine seltene aber erhebliche Komplikation im Verlauf einer Schwangerschaft. Die computertomographischen Veraenderungen im Gehirn sind bekannt. Mitteilungen von kernspintomographischen Befunden finden sich vor allem in der deutschen Literatur noch selten. Wir beschreiben das kernspintomographische Bild der zerebralen Veraenderungen bei Eklampsie und diskutieren die Vorteile der MRT im Vergleich zur CT. Die Gabe von Kontrastmittel bei der MRT weist zwar die Blut-Hirn-Schrankenstoerung nach, bringt aber keine therapeutisch relevanten Informationen. Sie sollte waehrend der Schwangerschaft vermieden werden. Ein frueher und gezielter Einsatz der MRT bei unklaren oder verdaechtigen neurologischen Symptomen waehrend der Schwangerschaft ist sinnvoll. Die MRT unterstuetzt die Differentialdiagnose in bezug auf nicht schwangerschaftsbezogene zerebrale Leiden und kann fuer die Therapie richtungweisend sein, wenn die Gestose noch nicht ausgepraegt ist. (orig.)

  5. Shoulder injuries in overhead sports; Schultergelenkverletzungen bei Ueberkopfsportarten

    Energy Technology Data Exchange (ETDEWEB)

    Woertler, K. [Technische Universitaet Muenchen (Germany). Institut fuer Roentgendiagnostik

    2010-05-15

    Overhead sport places great demands on the shoulder joint. Shoulder pain in overhead athletes and throwers can in the majority of cases be attributed to lesions resulting from chronic overuse of tendons and capsuloligamentous structures or to sequels of microinstability and secondary impingement. Due to its great impact on therapeutic decisions, imaging in athletes with unclear shoulder pain is a challenge. In this connection, magnetic resonance (MR) arthrography represents the cross-sectional imaging modality of first choice, as it allows depiction and exclusion of pathologic alterations of all relevant joint structures with sufficient confidence. This article reviews the biomechanical and clinical aspects and MR arthrographic features of the most common shoulder pathologies in overhead athletes, including biceps tendinopathy, superior labral anterior-posterior (SLAP) lesions, rotator cuff lesions, as well as extrinsic and intrinsic impingement syndromes. (orig.) [German] Ueberkopfsportarten stellen grosse Anforderungen an das Schultergelenk. Schulterbeschwerden bei Ueberkopf- und Wurfsportlern koennen in der Mehrzahl der Faelle auf eine chronische Ueberlastung von Sehnen und Kapsel-Band-Strukturen oder auf die Folgen einer Mikroinstabilitaet und sekundaerer Impingementsyndrome zurueckgefuehrt werden. Wegen ihres grossen Einflusses auf die Therapieentscheidung stellt die Bildgebung bei Athleten mit unklaren Schulterbeschwerden eine Herausforderung dar. Die MR-Arthrographie ist in diesem Zusammenhang als Schnittbildverfahren der ersten Wahl anzusehen, da sie den Nachweis bzw. Ausschluss pathologischer Veraenderungen aller relevanten Gelenkstrukturen mit ausreichender Sicherheit ermoeglicht. Dieser Artikel gibt eine Uebersicht ueber biomechanische und klinische Aspekte sowie MR-arthrographische Befunde der haeufigsten Schultergelenkpathologien bei Ueberkopfsportlern, wie Bizepstendinopathie, Superior-labral-anterior-posterior- (SLAP-)Laesionen, Laesionen der

  6. Imaging strategies for knee injuries; Bildgebungsstrategie bei Kniegelenkverletzungen

    Energy Technology Data Exchange (ETDEWEB)

    Hegenscheid, K.; Puls, R.; Rosenberg, C. [Ernst-Moritz-Arndt-Universitaet Greifswald, Institut fuer Diagnostische Radiologie und Neuroradiologie, Greifswald (Germany)

    2012-11-15

    Injuries of the knees are common. The Ottawa knee rule provides decisional support to determine whether radiographs are indicated or not. With the use of ultrasound it is possible to detect defects of the extensor ligaments and the anterior cruciate ligament. Furthermore, it is possible to detect indirect signs of an intra-articular fracture, e.g. lipohemarthrosis. In complex fractures, e.g. tibial plateau fractures, further diagnostic procedures with multislice computed tomography (CT) are needed for accurate classification and preoperative planning. Multislice CT with CT angiography enables three-dimensional reconstruction of the knee and non-invasive vascular imaging for detection of vascular injury. Magnetic resonance imaging (MRI) is the gold standard for detection of occult fractures and injuries of the ligaments and menisci. Higher field strengths can be used to improve the diagnostics of cartilage lesions. Virtual MR arthrography is superior to conventional MRI for detection of cartilage lesions especially after meniscus surgery. (orig.) [German] Verletzungen des Kniegelenks sind haeufig. Die Ottawa Knee Rule bietet eine Entscheidungshilfe dahingehend, ob Roentgenaufnahmen indiziert sind. Mittels Sonographie koennen Verletzungen des Streckapparats und vorderen Kreuzbandes erkannt werden. Ebenso gelingt der Nachweis eines Lipohaemarthros als indirektes Zeichen einer intraartikulaeren Fraktur. Bei komplexen Frakturen, z. B. Tibiaplateaufrakturen, ist eine weiterfuehrende Diagnostik mittels Multislice-CT zur Klassifizierung und praeoperativen Planung notwendig. Die Multislice-CT mit gleichzeitiger CT-Angiographie ermoeglicht die Anfertigung dreidimensionaler Rekonstruktionen und die nichtinvasive Gefaessdarstellung. Die Magnetresonanztomographie (MRT) ist der Goldstandard zum Nachweis okkulter Frakturen und Verletzungen an Baendern und Menisken. Bei hoeheren Feldstaerken verbessert sich die Diagnostik von Knorpellaesionen. Die virtuelle MR-Arthrographie ist

  7. Film dosimetry in conformal radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Danciu, C.; Proimos, B.S. [Patras Univ. (Greece). Dept. of Medical Physics

    1995-12-01

    Dosimetry, through a film sandwiched in a transverse cross-section of a solid phantom, is a method of choice in Conformal Radiotherapy because: (a) the blackness (density) of the film at each point offers a measure of the total dose received at that point, and (b) the film is easily calibrated by exposing a film strip in the same cross-section, through a stationary field. The film must therefore have the following properties: (a) it must be slow, in order not to be overexposed, even at a therapeutic dose of 200 cGy, and (b) the response of the film (density versus dose curve) must be independent of the photon energy spectrum. A few slow films were compared. It was found that the Kodak X-Omat V for therapy verification was the best choice. To investigate whether the film response was independent of the photon energy, response curves for six depths, starting from the depth of maximum dose to the depth of 25 cm, in solid phantom were derived. The vertical beam was perpendicular to the anterior surface of the phantom, which was at the distance of 100 cm from the source and the field was 15x15 cm at that distance. This procedure was repeated for photon beams emitted by a Cobalt-60 unit, two 6 MV and 15 MV Linear Accelerators, as well as a 45 MV Betatron. For each of those four different beams the film response was the same for all six depths. The results, as shown in the diagrams, are very satisfactory. The response curve under a geometry similar to that actually applied, when the film is irradiated in a transverse cross-section of the phantom, was derived. The horizontal beam was almost parallel (angle of 85) to the plane of the film. The same was repeated with the central ray parallel to the film (angle 90) and at a distance of 1.5 cm from the horizontal film. The field size was again 15x15 at the lateral entrance surface of the beam. The response curves remained the same, as when the beam was perpendicular to the films.

  8. Neutron dosimetry; Dosimetria de neutrons

    Energy Technology Data Exchange (ETDEWEB)

    Fratin, Luciano

    1993-12-31

    A neutron irradiation facility was designed and built in order to establish a procedure for calibrating neutron monitors and dosemeters. A 185 GBq {sup 241} Am Be source of known is used as a reference source. The irradiation facility using this source in the air provides neutron dose rates between 9 nSv s{sup -1} and 0,5 {sup {mu}}Sv s{sup -1}. A calibrated 50 nSv s{sup -1} thermal neutron field is obtained by using a specially designed paraffin block in conjunction with the {sup 241} Am Be source. A Bonner multisphere spectrometer was calibrated, using a procedure based on three methods proposed by international standards. The unfold {sup 241} Am Be neutron spectrum was determined from the Bonner spheres data and resulted in a good agreement with expected values for fluence rate, dose rate and mean energy. A dosimetric system based on the electrochemical etching of CR-39 was developed for personal dosimetry. The dosemeter badge using a (n,{alpha}) converter, the etching chamber and high frequency power supply were designed and built specially for this project. The electrochemical etching (ECE) parameters used were: a 6N KOH solution, 59 deg C, 20 kV{sub pp} cm{sup -1}, 2,0 kHz, 3 hours of ECE for thermal and intermediate neutrons and 6 hours for fast neutrons. The calibration factors for thermal, intermediate and fast neutrons were determined for this personal dosemeter. The sensitivities determined for the developed dosimetric system were (1,46{+-} 0,09) 10{sup 4} tracks cm{sup -2} mSv{sup -1} for thermal neutrons, (9{+-}3) 10{sup 2} tracks cm{sup -2} mSV{sup -1} for intermediate neutrons and (26{+-}4) tracks cm{sup -2} mSv{sup -1} for fast neutrons. The lower and upper limits of detection were respectively 0,002 mSv and 0,6 mSv for thermal neutrons, 0,04 mSv and 8 mSv for intermediate neutrons and 1 mSv and 12 mSv for fast neutrons. In view of the 1990`s ICRP recommendations, it is possible to conclude that the personal dosemeter described in this work is

  9. Chemoembolisation bei hepatozellulärem Karzinom (HCC

    Directory of Open Access Journals (Sweden)

    Cejna M

    2006-01-01

    Full Text Available Die transarterielle Chemoembolisation (TACE hat ihren Platz im multimodalen Therapieansatz des hepatozellulären Karzinoms (HCC. Zumeist erfolgt die Applikation von Doxorubicin, Mitomycin und Cisplatin mit Lipiodol, gefolgt von der Okklusion der versorgenden Arterie mit Partikeln zur Behandlung von nicht-resektablen HCC bei noch gut erhaltener Leberfunktion. Die Behandlungen erfolgen bis zum Nachweis eines Perfusionsstops des HCC. Verlaufskontrollen (Ultraschall, CT oder MRT sind unerläßlicher Bestandteil der Nachsorge. Mit superselektivem Zugang sind Komplikationen selten. Ähnliche Therapiekonzepte wie Permanentembolisation, Embolisation mit Chemotherapeutika-beladenen Partikeln oder Embolisation mit radioaktiven Partikeln sind derzeit in klinischer Erprobung.

  10. Diagnostic evaluation of deep vein thrombosis; Diagnostik bei tiefer Venenthrombose

    Energy Technology Data Exchange (ETDEWEB)

    Fuerst, G.; Saleh, A. [Universitaetsklinikum Duesseldorf (Germany). Inst. fuer Diagnostische Radiologie

    2001-12-01

    CT and MRI are efficient modalities for the imaging of venous thrombi. Their application currently is restricted to complementary use, in cases when results of US and/or phlebography leave open questions (as e.g. central extension of thrombi, assessment of causes, post-surgery follow-up). (orig./CB) [German] CT und MRT sind effiziente Techniken zur Venendarstellung bei Thrombose. Ihr Einsatz ist derzeit Fragestellungen vorbehalten, die sich sonographisch und/oder phlebographisch nicht ausreichend klaeren lassen (z. B. Thromboseausdehnung nach zentral, Ursachenabklaerung, postoperative Kontrollen). (orig.)

  11. Demenz und Depression bei Patienten mit idiopathischem Parkinson-Syndrom

    Directory of Open Access Journals (Sweden)

    Herting B

    2007-01-01

    Full Text Available Das idiopathische Parkinson-Syndrom (IPS ist eine progressive neurodegenerative Erkrankung mit motorischen und nicht-motorischen Symptomen. Bei Patienten mit IPS sind kognitive Defizite und Demenzen mit einer Prävalenz von 20–40 % nachgewiesen worden. Risikofaktoren für das Auftreten einer Parkinson-Demenz (PDe sind hohes Alter bei Krankheitsbeginn, schwere und/oder beidseitige motorische Symptomatik, Verwirrtheitszustände unter Levodopa-Medikation, aber auch Demenzerkrankungen in der Familie und niedriges Bildungsniveau. Patienten mit PDe weisen eine erhöhte Morbidität und Mortalität im Vergleich zu Patienten mit IPS ohne Demenz und der altersgleichen Normalbevölkerung auf, die unabhängig von der Schwere der motorischen Einbußen zweifach erhöht ist. Die Depression ist das häufigste psychiatrische Symptom beim IPS (die Angaben zur Prävalenz schwanken zwischen 4 % und 70 % und beeinflußt neben den Aktivitäten des täglichen Lebens wesentlich die Lebensqualität der Betroffenen. Darin liegt auch die Herausforderung, kognitive und affektive Symptome effizient zu behandeln.

  12. Thermoluminescence in medical dosimetry; Termoluminiscencia en dosimetria medica

    Energy Technology Data Exchange (ETDEWEB)

    Rivera, T., E-mail: trivera@ipn.mx [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, Col. Irrigacion, 11500 Mexico D. F. (Mexico)

    2011-10-15

    The dosimetry by thermoluminescence (Tl) is applied in the entire world for the dosimetry of ionizing radiations specially to personal and medical dosimetry. This dosimetry method has been very interesting for measures in vivo because the Tl dosimeters have the advantage of being very sensitive in a very small volume and they are also equivalent to tissue and they do not need additional accessories (for example, cable, electrometer, etc.) The main characteristics of the diverse Tl materials to be used in the radiation measures and practical applications are: the Tl curve, the share homogeneity, the signal stability after the irradiation, precision and exactitude, the response in function with the dose and the energy influence. In this work a brief summary of the advances of the radiations dosimetry is presented by means of the thermally stimulated luminescence and its application to the dosimetry in radiotherapy. (Author)

  13. Diagnostic evaluatuin of gastrointestinal tumors; Diagnostik bei Tumoren im Gastrointestinaltrakt

    Energy Technology Data Exchange (ETDEWEB)

    Linke, R.; Tatsch, K. [Ludwig-Maximilians-Univ. Muenchen (Germany). Klinik und Poliklinik fuer Nuklearmedizin

    1998-07-01

    difficult to distinguish between chronic pancreatitis and pancreatic carcinoma. In such cases a PET scan may be helpful. For planning of surgery and for preoperative staging morphological imaging is essential, but in nearly 40% of the patients nonresectable tumors were detected intraoperatively, which were not diagnosed by preoperative CT or MRI. PET seems to be more accurate in this respect, too. (orig.) [Deutsch] Hauptaufgaben der radiologischen und nuklearmedizinischen Diagnostik bei gastrointestinalen Tumoren sind Diagnosesicherung sowie praeoperatives Staging. Die Hohlorgane des oberen und unteren GI-Traktes (Oesophagus, Magen, Duodenum, Kolon, Rektum) werden primaer endoskopisch und endosonographisch abgeklaert. CT oder MRT liefern Informationen ueber Ausdehnung des Tumors, eine Infiltration in umgebende Strukturen und das Vorliegen pathologischer Lymphknoten. Das sensitivste Verfahren zum Nachweis von Lymphknoten- oder Fernmetastasen ist die PET. Auch die Differenzierung eines Lokalrezidivs von postoperativer Narbenbildung, z.B. beim kolorektalen Karzinom, gelingt mit der PET fruehzeitiger als mit den konventionellen morphologischen Verfahren. Lebertumoren sollten primaer sonographisch und bei fraglicher Dignitaet anschliessend mittels MRT untersucht werden. In der Differentialdiagnostik von unklaren Leberherden ist die nuklearmedizinische Rezeptorszintigraphie wegweisend. Benigne Leberlaesionen koennen mit der Neogalaktoalbumin-(NGA-)Szintigraphie sicher von malignen Tumoren (Metastasen, hepatozellulaeres Karzinom [HCC]) abgegrenzt werden, da NGA-Rezeptoren nur auf funktionstuechtigen Hepatozyten experimentiert werden. Die Unterscheidung von Lebermetastasen und dem HCC gelingt mit der Insulinszintigraphie, da sich Insulin aufgrund einer Ueberexpression von Insulinrezeptoren mit HCC vermehrt anreichert. Ergeben die vorgeschalteten Untersuchungen den Verdacht auf einen malignen Prozess, sollte zusaetzlich eine CT-Arterioportographie durchgefuehrt werden, da dieses

  14. TU-F-201-00: Radiochromic Film Dosimetry Update

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-06-15

    Since the introduction of radiochromic films (RCF) for radiation dosimetry, the scope of RCF dosimetry has expanded steadily to include many medical applications, such as radiation therapy and diagnostic radiology. The AAPM Task Group (TG) 55 published a report on the recommendations for RCF dosimetry in 1998. As the technology is advancing rapidly, and its routine clinical use is expanding, TG 235 has been formed to provide an update to TG-55 on radiochromic film dosimetry. RCF dosimetry applications in clinical radiotherapy have become even more widespread, expanding from primarily brachytherapy and radiosurgery applications, and gravitating towards (but not limited to) external beam therapy (photon, electron and protons), such as quality assurance for IMRT, VMAT, Tomotherapy, SRS/SRT, and SBRT. In addition, RCF applications now extend to measurements of radiation dose in particle beams and patients undergoing medical exams, especially fluoroscopically guided interventional procedures and CT. The densitometers/scanners used for RCF dosimetry have also evolved from the He-Ne laser scanner to CCD-based scanners, including roller-based scanner, light box-based digital camera, and flatbed color scanner. More recently, multichannel RCF dosimetry introduced a new paradigm for external beam dose QA for its high accuracy and efficiency. This course covers in detail the recent advancements in RCF dosimetry. Learning Objectives: Introduce the paradigm shift on multichannel film dosimetry Outline the procedures to achieve accurate dosimetry with a RCF dosimetry system Provide comprehensive guidelines on RCF dosimetry for various clinical applications One of the speakers has a research agreement from Ashland Inc., the manufacturer of Gafchromic film.

  15. Seed loss in prostate brachytherapy. Operator dependency and impact on dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    El-Bared, Nancy; Sebbag, Natanel; Beliveau-Nadeau, Dominic; Hervieux, Yannick; Larouche, Renee; Taussky, Daniel; Delouya, Guila [Centre hospitalier de l' Universite de Montreal - Hopital Notre-Dame, Departement de Radio-Oncologie, Montreal, QC (Canada)

    2016-05-15

    The aim of our study was to review seed loss and its impact on dosimetry as well as the influence of the treating physician on seed loss and dosimetry in patients treated with prostate brachytherapy using permanent loose {sup 125}I implant. We analyzed 1087 consecutive patients treated by two physicians between July 2005 and April 2015 at a single institution. Pelvic fluoroscopic imaging was done 30 days post implant and a chest X-ray when seed loss was observed. Seed loss occurred in 19.4 % of patients: in 20.0 % of implants done by the most experienced physician and in 17.2 % by the less experienced physician (p = 0.4) and migration to the thorax occurred in 5.9 % (6.9 vs. 2.2 %, p = 0.004). The mean seed loss rate was 0.57 % [standard deviation (SD) 1.39] and the mean rate of seeds in the thorax was 0.14 % (SD 0.65). The most experienced physician had a higher mean number of seeds lost: 0.36 versus 0.25 (p = 0.055), and a higher mean number of seed migration to the thorax: 0.1 versus 0.02 (p < 0.001). When at least one seed was lost, a decrease of 4.2 Gy (p < 0.001) in the D90 and a decrease of 3.5 % (p = 0.002) in the V150 was observed. We found a significant decrease in V150 and D90 with the occurrence of seed loss. Furthermore, we found a difference in seed migration among the physicians demonstrating that seed loss is operator dependant. (orig.) [German] Wir analysierten den Prozentsatz des Seed-Verlusts sowie den Einfluss von Arzterfahrung und Seed-Abgang auf die Dosimetrie bei Patienten, die mit einer Prostata-Brachytherapie mit permanent beweglichen {sup 125}I-Implantaten behandelt wurden. Eingeschlossen in diese Studie wurden alle zwischen Juli 2005 und April 2015 an unserem Krankenhaus von zwei Aerzten konsekutiv behandelten 1087 Patienten. Anhand fluoroskopischer Bilder wurden noch vorhandene Seeds 30 Tage nach dem Eingriff gezaehlt. Bei unvollstaendiger Seed-Anzahl wurde ein Thorax-Roentgenbild angefertigt. In 19% der Patienten ging mindestens ein

  16. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2005-02-25

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. Rev. 0 marks the first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database.

  17. Absolute and relative dosimetry for ELIMED

    Science.gov (United States)

    Cirrone, G. A. P.; Cuttone, G.; Candiano, G.; Carpinelli, M.; Leonora, E.; Lo Presti, D.; Musumarra, A.; Pisciotta, P.; Raffaele, L.; Randazzo, N.; Romano, F.; Schillaci, F.; Scuderi, V.; Tramontana, A.; Cirio, R.; Marchetto, F.; Sacchi, R.; Giordanengo, S.; Monaco, V.

    2013-07-01

    The definition of detectors, methods and procedures for the absolute and relative dosimetry of laser-driven proton beams is a crucial step toward the clinical use of this new kind of beams. Hence, one of the ELIMED task, will be the definition of procedures aiming to obtain an absolute dose measure at the end of the transport beamline with an accuracy as close as possible to the one required for clinical applications (i.e. of the order of 5% or less). Relative dosimetry procedures must be established, as well: they are necessary in order to determine and verify the beam dose distributions and to monitor the beam fluence and the energetic spectra during irradiations. Radiochromic films, CR39, Faraday Cup, Secondary Emission Monitor (SEM) and transmission ionization chamber will be considered, designed and studied in order to perform a fully dosimetric characterization of the ELIMED proton beam.

  18. Trigeminal neuralgia treatment dosimetry of the Cyberknife

    Energy Technology Data Exchange (ETDEWEB)

    Ho, Anthony [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Lo, Anthony T., E-mail: tonyho22003@yahoo.com [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Dieterich, Sonja; Soltys, Scott G.; Gibbs, Iris C. [Department of Radiation Oncology, Stanford University, Stanford, CA (United States); Chang, Steve G.; Adler, John R. [Department of Neurosurgery, Stanford University, Stanford, CA (United States)

    2012-04-01

    There are 2 Cyberknife units at Stanford University. The robot of 1 Cyberknife is positioned on the patient's right, whereas the second is on the patient's left. The present study examines whether there is any difference in dosimetry when we are treating patients with trigeminal neuralgia when the target is on the right side or the left side of the patient. In addition, we also study whether Monte Carlo dose calculation has any effect on the dosimetry. We concluded that the clinical and dosimetric outcomes of CyberKnife treatment for trigeminal neuralgia are independent of the robot position. Monte Carlo calculation algorithm may be useful in deriving the dose necessary for trigeminal neuralgia treatments.

  19. Absolute and relative dosimetry for ELIMED

    Energy Technology Data Exchange (ETDEWEB)

    Cirrone, G. A. P.; Schillaci, F.; Scuderi, V. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Institute of Physics Czech Academy of Science, ELI-Beamlines project, Na Slovance 2, Prague (Czech Republic); Cuttone, G.; Candiano, G.; Musumarra, A.; Pisciotta, P.; Romano, F. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania (Italy); Carpinelli, M. [INFN Sezione di Cagliari, c/o Dipartimento di Fisica, Università di Cagliari, Cagliari (Italy); Leonora, E.; Randazzo, N. [INFN-Sezione di Catania, Via Santa Sofia 64, Catania (Italy); Presti, D. Lo [INFN-Sezione di Catania, Via Santa Sofia 64, Catania, Italy and Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Raffaele, L. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and INFN-Sezione di Catania, Via Santa Sofia 64, Catania (Italy); Tramontana, A. [INFN, Laboratori Nazionali del Sud, Via Santa Sofia 62, Catania, Italy and Università di Catania, Dipartimento di Fisica e Astronomia, Via S. Sofia 64, Catania (Italy); Cirio, R.; Sacchi, R.; Monaco, V. [INFN, Sezione di Torino, Via P.Giuria, 1 10125 Torino, Italy and Università di Torino, Dipartimento di Fisica, Via P.Giuria, 1 10125 Torino (Italy); Marchetto, F.; Giordanengo, S. [INFN, Sezione di Torino, Via P.Giuria, 1 10125 Torino (Italy)

    2013-07-26

    The definition of detectors, methods and procedures for the absolute and relative dosimetry of laser-driven proton beams is a crucial step toward the clinical use of this new kind of beams. Hence, one of the ELIMED task, will be the definition of procedures aiming to obtain an absolute dose measure at the end of the transport beamline with an accuracy as close as possible to the one required for clinical applications (i.e. of the order of 5% or less). Relative dosimetry procedures must be established, as well: they are necessary in order to determine and verify the beam dose distributions and to monitor the beam fluence and the energetic spectra during irradiations. Radiochromic films, CR39, Faraday Cup, Secondary Emission Monitor (SEM) and transmission ionization chamber will be considered, designed and studied in order to perform a fully dosimetric characterization of the ELIMED proton beam.

  20. Technical basis document for internal dosimetry

    CERN Document Server

    Hickman, D P

    1991-01-01

    This document provides the technical basis for the Chem-Nuclear Geotech (Geotech) internal dosimetry program. Geotech policy describes the intentions of the company in complying with radiation protection standards and the as low as reasonably achievable (ALARA) program. It uses this policy and applicable protection standards to derive acceptable methods and levels of bioassay to assure compliance. The models and computational methods used are described in detail within this document. FR-om these models, dose- conversion factors and derived limits are computed. These computations are then verified using existing documentation and verification information or by demonstration of the calculations used to obtain the dose-conversion factors and derived limits. Recommendations for methods of optimizing the internal dosimetry program to provide effective monitoring and dose assessment for workers are provided in the last section of this document. This document is intended to be used in establishing an accredited dosi...

  1. Criticality accident dosimetry with ESR spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    D`Errico, F. [DCMN, Universita degli Studi di Pisa (Italy); Fattibene, P.; Onori, S.; Pantaloni, M. [Istituto Superiore di Sanita, Rome (Italy). Lab. di Fisica

    1997-01-01

    The suitability of the ESR alanine and sugar detectors for criticality accident dosimetry was experimentally investigated during an intercomparison of dosimetry techniques. Tests were performed irradiating detectors both free-in-air and on-phantom during controlled criticality excursions at the SILENE reactor in Valduc, France. Several grays of absorbed dose were imparted in neutron gamma-ray fields of various relative intensities and spectral distributions. Analysed results confirmed the potential of these systems which can immediately provide an acute dose assessment with an average underestimate of 30% in the various fields. This performance allows for the screening of severely exposed individuals and meets the IAEA recommendations on the early estimate of accident absorbed doses. (Author).

  2. Thermocurrent dosimetry with high purity aluminum oxide

    Energy Technology Data Exchange (ETDEWEB)

    Fullerton, G.D.; Cameron, J.R.; Moran, P.R.

    1976-01-01

    The application of thermocurrent (TC) to ionizing radiation dosimetry was studied. It was shown that TC in alumina (Al/sub 2/O/sub 3/) has properties that are suited to personnel dosimetry and environmental monitoring. TC dosimeters were made from thin disks of alumina. Aluminum electrodes were evaporated on each side: on one face a high voltage electrode and on the opposite face a measuring electrode encircled by a guard ring. Exposure to ionizing radiation resulted in stored electrons and holes in metastable trapping sites. The signal was read-out by heating the dosimeter with a voltage source and picnometer connected in series between the opposite electrodes. The thermally remobilized charge caused a transient TC. The thermogram, TC versus time or temperature, is similar to a TL glow curve. Either the peak current or the integrated current is a measure of absorbed dose. Six grades of alumina were studied from a total of four commercial suppliers. All six materials displayed radiation induced TC signals. Sapphire of uv-grade quality from the Adolf Meller Co. (AM) had the best dosimetry properties of those investigated. Sources of interference were studied. Thermal fading, residual signal and radiation damage do not limit TC dosimetry. Ultraviolet light can induce a TC response but it is readily excluded with uv-opaque cladding. Improper surface preparation prior to electrode evaporation was shown to cause interference. A spurious TC signal resulted from polarization of surface contaminants. Spurious TC was reduced by improved cleaning prior to electrode application. Polished surfaces resulted in blocking electrodes and caused a sensitivity shift due to radiation induced thermally activated polarization. This was not observed with rough cut surfaces.

  3. Report: dosimetry of diagnostic exams in nuclear medicine; Rapport: dosimetrie des explorations diagnostiques en medecine nucleaire

    Energy Technology Data Exchange (ETDEWEB)

    Touzery, C. [Centre Regional de Lutte Contre le Cancer de Bourgogne, Centre Georges-Francois Leclerc, 21 - Dijon (France); Aubert, B. [Institut Gustave Roussy, 94 - Villejuif (France); Caselles, O. [Centre Claudius-Regaud, 31 - Toulouse (France); Gardin, I. [Centre Henri Becquerel, 76 - Rouen (France); Guilhem, M.Th. [Centre Hospitalier Regional de la Source, 45 - Orleans (France); Laffont, S. [Centre Eugene-Marquis, 35 - Rennes (France); Lisbona, A. [Centre Regional de Lutte Contre le Cancer Rene-Gauducheau, 44 - Nantes (France)

    2002-07-01

    A compilation about dosimetry of diagnosis explorations in nuclear medicine is presented in this issue. Dosimetry tables of the different radiopharmaceuticals used in nuclear medicine give indications on absorbed and efficient doses according the patients age from one year to adult age. The doses received by a fetus during a lung scintigraphy realized for the pregnant woman susceptible to suffer of pulmonary emboli is presented. A table of efficient doses for the infants until the age of six months for the principal scintigraphy explorations realized in nuclear medicine are given. A chapter of theoretical headlines is devoted to dosimetry and the calculations methods of absorbed and efficient doses in function of patients age. A short chapter concerns the recommendations to explore nursing mothers by scintigraphy. A last chapter treats the efficient doses received during explorations using ionizing radiations in radiology and their place in annual natural irradiation scale. (N.C.)

  4. Reconstructive dosimetry for cutaneous radiation syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Lima, C.M.A.; Lima, A.R.; Degenhardt, Ä.L.; Da Silva, F.C.A., E-mail: dasilva@ird.gov.br [Instituto de Radioprotecao e Dosimetria (IRD/CNEN-RJ), Rio de Janeiro, RJ (Brazil); Valverde, N.J. [Fundacao Eletronuclear de Assistencia Medica, Rio de Janeiro, RJ (Brazil)

    2015-10-15

    According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry. (author)

  5. Hanford Internal Dosimetry Project manual. Revision 1

    Energy Technology Data Exchange (ETDEWEB)

    Carbaugh, E.H.; Bihl, D.E.; MacLellan, J.A.; Long, M.P.

    1994-07-01

    This document describes the Hanford Internal Dosimetry Project, as it is administered by Pacific Northwest Laboratory (PNL) in support of the US Department of Energy and its Hanford contractors. Project services include administrating the bioassay monitoring program, evaluating and documenting assessment of potential intakes and internal dose, ensuring that analytical laboratories conform to requirements, selecting and applying appropriate models and procedures for evaluating radionuclide deposition and the resulting dose, and technically guiding and supporting Hanford contractors in matters regarding internal dosimetry. Specific chapters deal with the following subjects: practices of the project, including interpretation of applicable DOE Orders, regulations, and guidance into criteria for assessment, documentation, and reporting of doses; assessment of internal dose, including summary explanations of when and how assessments are performed; recording and reporting practices for internal dose; selection of workers for bioassay monitoring and establishment of type and frequency of bioassay measurements; capability and scheduling of bioassay monitoring services; recommended dosimetry response to potential internal exposure incidents; quality control and quality assurance provisions of the program.

  6. Electron paramagnetic resonance dosimetry using synthetic hydroxyapatite

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Kwon; Kim, Hwi Young; Ye, Sung Joon [Seoul National University, Seoul (Korea, Republic of); Hirata, Hiroshi [Hokkaido University, Sapporo (Japan); Park, Jong Min [Seoul National University Hospital, Seoul (Korea, Republic of)

    2014-11-15

    The victims exposed doses under 3.5-4.0 Gy have chance to survive if treated urgently. To determine the priority of treatment among a large number of victims, the triage – distinguishing patients who need an urgent treatment from who may not be urgent – is necessary based on radiation biodosimetry. A current gold standard for radiation biodosimetry is the chromosomal assay using human lymphocytes. But this method requires too much time and skilled labors to cover the mass victims in radiation emergencies. Electron paramagnetic resonance (EPR) has been known for its capability of quantifying radicals in matters. EPR dosimetry is based on the measurement of stable radiation-induced radicals in tooth enamel. Hydroxyapatite (HAP) (Ca10(PO4)6(OH)2) contained in tooth enamel is a major probe for radiation dose reconstruction. This HAP dosimetry study was performed using a novel EPR spectrometer in Hokkaido University, Japan. The EPR dose-response curve was made using HAP samples. The blind test using 250 cGy samples showed the feasibility of EPR dosimetry for the triage purpose.

  7. Reconstructive dosimetry for cutaneous radiation syndrome.

    Science.gov (United States)

    Lima, C M A; Lima, A R; Degenhardt, Ä L; Valverde, N J; Silva, F C A da

    2015-10-01

    According to the International Atomic Energy Agency (IAEA), a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS) in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry.

  8. Reconstructive dosimetry for cutaneous radiation syndrome

    Directory of Open Access Journals (Sweden)

    C.M.A. Lima

    2015-01-01

    Full Text Available According to the International Atomic Energy Agency (IAEA, a relatively significant number of radiological accidents have occurred in recent years mainly because of the practices referred to as potentially high-risk activities, such as radiotherapy, large irradiators and industrial radiography, especially in gammagraphy assays. In some instances, severe injuries have occurred in exposed persons due to high radiation doses. In industrial radiography, 80 cases involving a total of 120 radiation workers, 110 members of the public including 12 deaths have been recorded up to 2014. Radiological accidents in industrial practices in Brazil have mainly resulted in development of cutaneous radiation syndrome (CRS in hands and fingers. Brazilian data include 5 serious cases related to industrial gammagraphy, affecting 7 radiation workers and 19 members of the public; however, none of them were fatal. Some methods of reconstructive dosimetry have been used to estimate the radiation dose to assist in prescribing medical treatment. The type and development of cutaneous manifestations in the exposed areas of a person is the first achievable gross dose estimation. This review article presents the state-of-the-art reconstructive dosimetry methods enabling estimation of local radiation doses and provides guidelines for medical handling of the exposed individuals. The review also presents the Chilean and Brazilian radiological accident cases to highlight the importance of reconstructive dosimetry.

  9. Software tool for portal dosimetry research.

    Science.gov (United States)

    Vial, P; Hunt, P; Greer, P B; Oliver, L; Baldock, C

    2008-09-01

    This paper describes a software tool developed for research into the use of an electronic portal imaging device (EPID) to verify dose for intensity modulated radiation therapy (IMRT) beams. A portal dose image prediction (PDIP) model that predicts the EPID response to IMRT beams has been implemented into a commercially available treatment planning system (TPS). The software tool described in this work was developed to modify the TPS PDIP model by incorporating correction factors into the predicted EPID image to account for the difference in EPID response to open beam radiation and multileaf collimator (MLC) transmitted radiation. The processes performed by the software tool include; i) read the MLC file and the PDIP from the TPS, ii) calculate the fraction of beam-on time that each point in the IMRT beam is shielded by MLC leaves, iii) interpolate correction factors from look-up tables, iv) create a corrected PDIP image from the product of the original PDIP and the correction factors and write the corrected image to file, v) display, analyse, and export various image datasets. The software tool was developed using the Microsoft Visual Studio.NET framework with the C# compiler. The operation of the software tool was validated. This software provided useful tools for EPID dosimetry research, and it is being utilised and further developed in ongoing EPID dosimetry and IMRT dosimetry projects.

  10. Diagnostic radiology dosimetry: status and trends

    Energy Technology Data Exchange (ETDEWEB)

    Rivera M, T., E-mail: trivera@ipn.mx [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, 11500 Mexico D. F. (Mexico)

    2015-10-15

    Full text: Medical radiation is by far the largest man-made source of public exposure to ionizing radiation. Since 1970 the expression of protection standards shifted from a dose- to a risk-based approach, with dose limits established to yield risks to radiation workers comparable with those for workers in other safe industries. Another hand, worldwide interest in patient dose measurement was stimulated by the publication of Patient Dose Reduction in Diagnostic Radiology by the UK National Radiological Protection Board (NRPB). In response to heightened awareness of the importance of patient dose contributed by radiology procedures, there has been a general trend to effect control of patient doses by applying the principles of optimization coupled with an increase in regulatory enforcement. In this sense, thermoluminescent dosimetry (TLD) has been actively proposed in the last 3 decades thanks to their successful applications in diagnostic radiology. At the same time, it is emerged as the best radiation dosimetry method. The present work presents advantages of thermoluminescent dosimetry for X-ray beams measurements and its optimization. (Author)

  11. Methodological aspects of EPR dosimetry with teeth

    Energy Technology Data Exchange (ETDEWEB)

    Sholom, S.; Chumak, V. [Scientific Center for Radiation Medicine, Kiev (Ukraine)

    2001-07-01

    EPR dosimetry with tooth enamel is known today as one of the most reliable and accurate methods of retrospective dosimetry. In the present study a comprehensive analysis of influence of the major confounding factors (solar UV exposure and dental X-ray diagnostic procedures) on the accuracy of accidental dose reconstruction is given. In this analysis, the facts known from literature as well as own authors' results were considered. Among the latter it is worth to mention study of doses in enamel caused by X-ray diagnostic procedures as well as investigation of dose profiles in front teeth, which are most affected to solar radiation. As a main result, the variant of dosimetric technique is proposed. It comprises the optimal combination of strongest sides of existing techniques which allows to conduct routine reconstruction of accidental doses as low as few tens of mGy with errors of the same order of magnitude. The proposed technique is primarily destined for dosimetry of Chernobyl liquidators, but could be used for reconstruction of doses of other over-exposed categories. (orig.)

  12. In vivo dosimetry in external beam radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Mijnheer, Ben [Department of Radiation Oncology, Netherlands Cancer Institute-Antoni van Leeuwenhoek Hospital, Amsterdam 1066 CX (Netherlands); Beddar, Sam [Department of Radiation Physics, University of Texas MD Anderson Cancer Center, Houston, Texas 77030 (United States); Izewska, Joanna [Division of Human Health, International Atomic Energy Agency, Vienna 1400 (Austria); Reft, Chester [Department of Radiation and Cellular Oncology, University of Chicago Medical Center, Chicago, Illinois 60637 (United States)

    2013-07-15

    In vivo dosimetry (IVD) is in use in external beam radiotherapy (EBRT) to detect major errors, to assess clinically relevant differences between planned and delivered dose, to record dose received by individual patients, and to fulfill legal requirements. After discussing briefly the main characteristics of the most commonly applied IVD systems, the clinical experience of IVD during EBRT will be summarized. Advancement of the traditional aspects of in vivo dosimetry as well as the development of currently available and newly emerging noninterventional technologies are required for large-scale implementation of IVD in EBRT. These new technologies include the development of electronic portal imaging devices for 2D and 3D patient dosimetry during advanced treatment techniques, such as IMRT and VMAT, and the use of IVD in proton and ion radiotherapy by measuring the decay of radiation-induced radionuclides. In the final analysis, we will show in this Vision 20/20 paper that in addition to regulatory compliance and reimbursement issues, the rationale for in vivo measurements is to provide an accurate and independent verification of the overall treatment procedure. It will enable the identification of potential errors in dose calculation, data transfer, dose delivery, patient setup, and changes in patient anatomy. It is the authors' opinion that all treatments with curative intent should be verified through in vivo dose measurements in combination with pretreatment checks.

  13. Sensitivity studies associated with dosimetry experiment interpretation

    Energy Technology Data Exchange (ETDEWEB)

    Bourganel, S.; Soldevila, M. [CEA/DANS/DM2S/SERMA, CEA Saclay, 91191, Gif sur Yvette (France); Ferrer, A.; Gregoire, G.; Destouches, C.; Beretz, D. [CEA/DEN-CAD/DER/SPEX, CEA Cadarache, F13108, Saint Paul lez Durance (France)

    2011-07-01

    Document available in abstract form only, full text of document follows: Interpretation of reactor dosimetry experiments with C/E comparison requires precise knowledge of parameters involved in modeling. Some parameters have more weight than others on the calculated values. So, sensitivity studies should be conducted to verify the importance of these parameters. The conclusions of these studies are used to refine the experiment modeling, or to correct uncertainty calculations. The results of these sensitivity studies allow a post-irradiation analysis, which can justify the discarding of some atypical C/M values. Derived uncertainties may be improved by the sensitivity analyses. Beyond classical parameters as geometry or composition, this paper describes some specific sensitivity studies conducted for dosimetry irradiation in reactor, and presents conclusions. These studies are based on dosimeters irradiated in the EOLE reactor facility at Cadarache CEA center. Conclusions drawn from these studies are generic and can be applied to any dosimetry study. Calculations performed for these studies were realized using TRIPOLI-4 Monte Carlo code. (authors)

  14. Patient dosimetry in classical radiology;Dosimetrie patient en radiologie classique

    Energy Technology Data Exchange (ETDEWEB)

    Valero, M. [Autorite de Surete Nucleaire, 75 Paris (France); Sirinelli, D. [Tours Univ., 37 (France); Chateil, J.F. [CHU Bordeaux, 33 (France)

    2009-10-15

    The objective is to give to the participants the means to determine, by simple methods, the dose delivered to skin during a radiological examination (conventional or numerical). The message to remember is: the use of a numerical detector does not lead systematically to reduce the dose at the patient. The dose.length product is a risk indicator. It is important to compare our practices to the procedures written in the guide of procedures and to note and to send to I.R.S.N. the dosimetry data relative to the dosimetry reference levels. (N.C.)

  15. Dosimetry tools and techniques for IMRT.

    Science.gov (United States)

    Low, Daniel A; Moran, Jean M; Dempsey, James F; Dong, Lei; Oldham, Mark

    2011-03-01

    Intensity modulated radiation therapy (IMRT) poses a number of challenges for properly measuring commissioning data and quality assurance (QA) radiation dose distributions. This report provides a comprehensive overview of how dosimeters, phantoms, and dose distribution analysis techniques should be used to support the commissioning and quality assurance requirements of an IMRT program. The proper applications of each dosimeter are described along with the limitations of each system. Point detectors, arrays, film, and electronic portal imagers are discussed with respect to their proper use, along with potential applications of 3D dosimetry. Regardless of the IMRT technique utilized, some situations require the use of multiple detectors for the acquisition of accurate commissioning data. The overall goal of this task group report is to provide a document that aids the physicist in the proper selection and use of the dosimetry tools available for IMRT QA and to provide a resource for physicists that describes dosimetry measurement techniques for purposes of IMRT commissioning and measurement-based characterization or verification of IMRT treatment plans. This report is not intended to provide a comprehensive review of commissioning and QA procedures for IMRT. Instead, this report focuses on the aspects of metrology, particularly the practical aspects of measurements that are unique to IMRT. The metrology of IMRT concerns the application of measurement instruments and their suitability, calibration, and quality control of measurements. Each of the dosimetry measurement tools has limitations that need to be considered when incorporating them into a commissioning process or a comprehensive QA program. For example, routine quality assurance procedures require the use of robust field dosimetry systems. These often exhibit limitations with respect to spatial resolution or energy response and need to themselves be commissioned against more established dosimeters. A chain of

  16. Cryotherapy in rheumatic disorders; Kryotherapie bei rheumatischen Erkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Soerensen, H. [Rheumaklinik Immanuel-Krankenhaus, Berlin (Germany). Innere Rheumatologische Abt.

    1994-12-31

    When applied locally, cold therapy (cryotherapy) has the effect of inhibiting inflammation, occluding blood vessels, and stopping bleeding. Active rheumatic inflammation, activated arthrosis, and swelling after injury can be alleviated by local cold application, while heat application would worsen the situation. In whole-body cryotherapy the whole patient, wearing only a bathing suit, is exposed to a temperature of -100 C. The present paper descrcribes the cold room of the Immanuel Hospital in Berlin-Wannsee. (BWI) [Deutsch] Kaeltetherapie (Kryotherapie) wirkt lokal angewendet entzuendungshemmend, blutgefaessabdichtend und blutstillend. Eine aktive rheumatische Entzuendung, aktivierte Arthrose und Schwellungsreaktionen bei Verletzungen werden durch lokale Kaelteanwendungen gedaempft, wogegen Waerme den akuten Zustand verschlimmern wuerde. In der Ganzkoerperkaeltetherapie wird der ganze Mensch in Badebekleidung einer realen Temperatur von -100 C ausgesetzt. Der vorliegende Beitrag beschreibt die Kaeltekammer des Immanuel Krankenhauses in Berlin Wannsee. (BWI)

  17. Quantifizierung neurodegenerativer Veränderungen bei der Alzheimer Krankheit

    Science.gov (United States)

    Fritzsche, Klaus H.; Giesel, Frederik L.; Thomann, Philipp A.; Hahn, Horst K.; Essig, Marco; Meinzer, Hans-Peter

    Die objektive Bewertung neurodegenerativer Prozesse stellt für die Diagnose und Therapiebegutachtung neuropsychiatrischer Krankheiten eine wichtige Grundlage dar. Computerbasierte radiodiagnostische Verfahren können pathologische Veränderungen in verschiedenen Hirnarealen quantifizieren und hierbei die rein visuelle Beurteilung der Bilddaten ergänzen. Inhalt dieser Studie ist die Evaluation einer voll automatischen Methode zur voxelbasierten Messung atrophischer Veränderungen im Gehirn, wie sie bei der Alzheimer-Demenz (AD) oder der leichten kognitiven Störung (LKS) auftreten. Es wurde eine signifikante Korrelation mit den semiautomatisch extrahierten Volumina der Temporalhörner festgestellt. Die Präzision, Benutzerfreundlichkeit, Beobachterunabh ängigkeit sowie die kurze Rechenzeit des automatischen Verfahrens sind wichtige Voraussetzungen für den routinemäßigen klinischen Einsatz.

  18. Aktuelle Therapieansätze bei der alkoholischen Lebererkrankung

    Directory of Open Access Journals (Sweden)

    Renner F

    2006-01-01

    Full Text Available Alkohol ist einer der wichtigsten Auslöser oder aggravierenden Faktoren für chronische und akute Lebererkrankungen. Pathophysiologisch sind neben nutritiven Defiziten vor allem eine direkte Alkoholtoxizität mit vermehrter Bildung freier Radikale, konsekutiver Störungen des Intermediärstoffwechsels und schließlich eine inadäquate Zytokinaktivierung von Bedeutung. Dementsprechend sind Abstinenz, Ausgleich kalorischer Defizite, sowie bei der schweren Alkoholhepatitis die Gabe von Steroiden und der Einsatz von Pentoxifyllin zur Vermeidung des hepatorenalen Syndroms von gesicherter therapeutischer Effizienz. Die Lebertransplantation hat sich insbesonders in Kombination mit Abstinenz als effizienteste Therapie der alkoholischen Leberzirrhose erwiesen. Leberschutzpräparate und gezielte Nahrungsmittelergänzungen sind von nicht gesichertem Nutzen, über Tumornekrosefaktor- (TNF- alpha Antikörper und Insulinsensitizer liegen erste Ergebnisse vor.

  19. Konservative und operative Therapie bei Harninkontinenz, Deszensus und Urogenitalbschwerden

    Directory of Open Access Journals (Sweden)

    Eberhard J

    2000-01-01

    Full Text Available Urogynäkologische Beschwerden wie Harninkontinenz, Infektionen, vulvo-vaginale und vesikale Reizzustände, Juckreiz, Dyspareunie, Beckenbodenschwäche, Deszensusbeschwerden werden in irgendeiner Form bei fast jeder Frau im Laufe ihres Lebens zur behandlungsbedürftigen Krankheit. Die Ursachen dieser häufigsten Frauenleiden sind vielfältig. Eine erfolgreiche Therapie sollte auf der Polyätiologie urogynäkologischer Krankheiten aufbauen und die verschiedenen Therapiemöglichkeiten zu einem patienten- und krankheitsadaptierten Behandlungskonzept zusammenfügen. Die Bausteine der konservativen Therapie sind: Trink- und Miktionstraining, Physiotherapie mit den Hilfsmitteln Kugeln, Kegel, Elektrostimulation und Biofeedbackmethoden; Östrogene, Pessare, Infekttherapie, Intimpflege, blasenrelaxierende und andere urogynäkologische Medikamente. Der Einsatz dieser Therapiebausteine wird ausführlich besprochen. Auch wird gezeigt, wann und wie operiert werden soll, wenn die konservative Therapie nicht zum Ziel führt.

  20. Pathophysiologie des Kollagenstoffwechsels bei Patienten mit Induratio penis plastica (IPP

    Directory of Open Access Journals (Sweden)

    Lahme S

    2000-01-01

    Full Text Available Die Pathogenese der IPP ist bis heute nicht geklärt. Histopathologische Untersuchungen zeigen, daß der Kollagenstoffwechsel eine Rolle spielt. Dies veranlaßte uns zur genauen Analyse der Kollagenstoffwechselparameter bei IPP. Bei 11 Patienten mit IPP und 11 Kontrollpersonen wurden Kollagenstoffwechselparameter (Prokollagen III [PIIIP], PMN-Elastase [PMN-E], Fibronektin [FN], Fibronektinrezeptor [FN-R] und alpha1-Proteinase-Inhibitor [alpha1-PI] im cavernösen und peripheren Blut bestimmt. PMN-E, PIIIP, FN und FN-R waren in den beiden Untersuchungsgruppen nicht unterschiedlich. Die peripher venösen unterschieden sich nicht von den cavernösen Blutproben. Sowohl im peripher venös (158,55 mg/dl als auch im cavernös entnommenen Blut (168,29 mg/dl war die Konzentration des a1-PI signifikant niedriger als in der Kontrollgruppe (214,82 mg/dl. An einem zweiten Kollektiv von 23 Patienten wurden Analysen des Phänotyps für alpha1-PI im Hinblick auf das Vorliegen von genetisch determinierten Mangelallelen vorgenommen. Hier zeigte sich kein signifikanter Unterschied zu einem Kontrollkollektiv von 19 gesunden Probanden. Die alpha1-PI Erniedrigung der IPP-Patienten ist signifikant und liegt unterhalb des Normalwertbereichs für die gesunde Population. Ein Mangel an alpha1-PI kann zur Aktivitätserhöhung der Proteasen und zum Umbau des Kollagengewebes führen. Möglicherweise kommt es zusammen mit einem lokal wirksamen Einflußfaktor schließlich zur dystrophen Kalzifikation. Die humangenetischen Untersuchungen sprechen nicht für eine genetische Determinierung des alpha1-PI-Mangels, sondern legen eine erworbene hepatische Störung nahe.

  1. MRI in dementia-type diseases; MRT bei demenziellen Erkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Bodea, S.V.; Muehl-Benninghaus, R. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg (Germany)

    2015-05-01

    Dementia-inducing conditions represent a leading cause of disability and are a major health concern in industrialized countries. The burden these conditions put on society is certain to rise in the context of an ever-increasing elderly population. As these conditions feature an insidious onset and overlapping clinical features, imaging is a powerful tool in refining the diagnosis and assessing the progression of dementing conditions. The radiologist needs to be aware of and be able to detect underlying pathologies which could be reversible. Furthermore, imaging is important not only in excluding other pathologies but also in improving diagnostic accuracy. This article presents the typical clinical presentations as well as magnetic resonance imaging (MRI) features of the degenerative and the non-degenerative causes of dementia. The focus is on the core knowledge for MRI diagnostics in dementing conditions and a brief presentation of the latest MRI techniques which may become a part of standard imaging protocols in the future. (orig.) [German] Demenzielle Erkrankungen gehoeren in den Industrielaendern zu den haeufigsten Ursachen fuer Beeintraechtigungen im Alltag. Durch eine stetig alternde Population nimmt auch die Belastung fuer die Gesellschaft immer weiter zu. Bei haeufig schleichendem Symptombeginn sowie sich ueberlappender Klinik mit anderen Krankeitsbildern kann die Bildgebung ein gutes Werkzeug zur Praezisierung der Diagnose und Beurteilung eines Progresses sein. Der Radiologe sollte andere und reversible Pathologien erkennen und von demenztypischen Veraenderungen abgrenzen koennen. Dieser Artikel beschreibt typische klinische Symptome und auch bildmorphologische Veraenderungen verschiedener Demenzformen, die durch neurodegenerative und nichtdegenerative Ursachen bedingt sein koennen. Ausserdem werden aktuellste MRT-Techniken vorgestellt. Diese koennten kuenftig im Standartprotokoll zur Bildgebung bei der Abklaerung demenzieller Syndrome verankert sein. (orig.)

  2. Molecular imaging in neurological diseases; Molekulare Bildgebung bei neurologischen Erkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Reimold, M.; Fougere, C. la [Universitaetsklinikum Tuebingen, Abteilung Nuklearmedizin und Klinische Molekulare Bildgebung, Department Radiologie, Tuebingen (Germany)

    2016-07-15

    In neurodegeneration and in neuro-oncology, the standard imaging procedure, magnetic resonance imaging (MRI), shows limited sensitivity and specificity. Molecular imaging with specific positron-emission tomography (PET) and single-photon emission computed tomography (SPECT) tracers allows various molecular targets and metabolic processes to be assessed and is thus a valuable adjunct to MRI. Two important examples are referred to here: amino acid transport for neuro-oncological issues, and the recently approved PET tracers for detecting amyloid depositions during the preclinical stage of Alzheimer's disease. This review discusses the clinical relevance and indications for the following nuclear medicine imaging procedures: amyloid PET, {sup 18}F-fluorodeoxyglucose (FDG)-PET, and dopamine transporter (DaT)-SPECT for the diagnosis of dementia and the differential diagnosis of Parkinson's disease, in addition to amino acid PET for the diagnosis of brain tumors and somatostatin receptor imaging in meningioma. (orig.) [German] Die Magnetresonanztomographie (MRT) weist als Standardverfahren bei neurodegenerativen und neuroonkologischen Fragestellungen eine eingeschraenkte Sensitivitaet und Spezifitaet auf. Die nuklearmedizinische molekulare Bildgebung mit spezifischen Positronenemissionstomographie(PET)- und single-photon-emission-computed-tomography(SPECT)-Tracern ermoeglicht die Darstellung verschiedener molekularer Targets bzw. Stoffwechselprozesse und stellt damit eine wichtige Ergaenzung zur MRT dar. Hier sei exemplarisch auf die Darstellung des Aminosaeuretransports im Rahmen neuroonkologischer Fragestellungen verwiesen, sowie auf die bereits im praeklinischen Stadium der Alzheimer-Demenz nachweisbaren Amyloidablagerungen mit hierfuer seit Kurzem zugelassenen PET-Tracern. Dieser Uebersichtsbeitrag bespricht die klinische Bedeutung bzw. die Indikationen der folgenden nuklearmedizinischen Untersuchungsverfahren: der Amyloid-PET, der {sup 18}F

  3. Therapeutische Überlegungen bei sensomotorischer diabetischer Neuropathie

    Directory of Open Access Journals (Sweden)

    Bührlen M

    2013-01-01

    Full Text Available Der Begriff der sensomotorischen diabetischen Neuropathie beschreibt einen heterogenen Beschwerdekomplex, der auf einer diabetesbedingten Schädigung des peripheren Nervensystems beruht. Bis zu 50 % der Menschen mit Diabetes mellitus leiden im Verlauf ihrer Erkrankung an Symptomen einer sensomotorischen Neuropathie. Chronische Schmerzen, Dysund Parästhesien sowie die Komplikation des diabetischen Fußsyndroms stellen für die Betroffenen gravierende Folgen dar. Die Optimierung der metabolischen Kontrolle stellt eine wichtige Basismaßnahme dar. Andere, zweifelsfrei gesicherte Möglichkeiten der Prävention oder kausalen Therapie sind nicht bekannt. Bei Auftreten einer schmerzhaften Neuropathie sollte eine gezielte analgetische Therapie möglichst früh begonnen werden. Mit den trizyklischen Antidepressiva, Duloxetin, Gabapentin und Pregabalin stehen Wirkstoffe zur Verfügung, die eine spezifische Therapie neuropathischer Schmerzen ermöglichen. Dabei ist zu beachten, dass in der Regel keine Schmerzfreiheit erreicht werden kann. Entscheidend ist das Erreichen eines für den Patienten tolerablen Schmerzniveaus unter Minimierung medikamentenassoziierter Nebenwirkungen. Das individuelle Ansprechen auf ein Medikament und die optimale Dosis können nicht vorhergesagt, sondern müssen individuell erprobt werden. Bei leichten Schmerzen können die Nicht-Opioid- Analgetika Paracetamol und Metamizol eingesetzt werden. Fehlen Therapiealternativen, dann stellen Opioide eine weitere Möglichkeit der Therapie starker Schmerzen dar. Aufgrund einer zusätzlichen Monoamin-Wiederaufnahmehemmerwirkung nehmen Tramadol und Tapentadol in dieser Gruppe eine Sonderstellung ein. In der Risiko- Nutzen-Abwägung darf das Nebenwirkungs- und Abhängigkeitspotenzial der Opioide in der Langzeittherapie nicht unterschätzt werden. Für andere medikamentöse Therapien oder alternative Therapiemethoden liegt keine ausreichende wissenschaftliche Evidenz vor. Sie können aber im

  4. Dosimetry intercomparisons in European medical device sterilization plants

    DEFF Research Database (Denmark)

    Miller, A.; Sharpe, P.H.G.

    2000-01-01

    Dosimetry intercomparisons have been carried out involving two-thirds of all European radiation sterilization facilities. Dosimeters for the intercomparisons were supplied by two accredited calibration laboratories. The results show good agreement, and indicate overall dosimetry accuracy of the o...... of the order of +/-5% (1 sigma) for both Co-60 and electron beam plants. (C) 2000 Elsevier Science Ltd. All rights reserved....

  5. [Instrumental radiofrequency electromagnetic radiation dosimetry: general principals and modern methodology].

    Science.gov (United States)

    Perov, S Iu; Kudriashov, Iu B; Rubtsova, N B

    2012-01-01

    The modern experimental radiofrequency electromagnetic field dosimetry approach has been considered. The main principles of specific absorbed rate measurement are analyzed for electromagnetic field biological effect assessment. The general methodology of specific absorbed rate automated dosimetry system applied to establish the compliance of radiation sources with the safety standard requirements (maximum permissible levels and base restrictions) is described.

  6. Neutron dosimetry and radiation damage calculations for HFBR

    Energy Technology Data Exchange (ETDEWEB)

    Greenwood, L.R.; Ratner, R.T. [Pacific Northwest National Lab., TN (United States)

    1998-03-01

    Neutron dosimetry measurements have been conducted for various positions of the High Flux Beam Reactor (HFBR) at Brookhaven National Laboratory (BNL) in order to measure the neutron flux and energy spectra. Neutron dosimetry results and radiation damage calculations are presented for positions V10, V14, and V15.

  7. Use of the GATE Monte Carlo package for dosimetry applications

    Energy Technology Data Exchange (ETDEWEB)

    Visvikis, D. [INSERM U650, LaTIM, University Hospital Medical School, F 29609 Brest (France)]. E-mail: Visvikis.Dimitris@univ-brest.fr; Bardies, M. [INSERM U601, CHU Nantes, F 44093 Nantes (France); Chiavassa, S. [INSERM U601, CHU Nantes, F 44093 Nantes (France); Danford, C. [Department of Medical Physics, MSKCC, New York (United States); Kirov, A. [Department of Medical Physics, MSKCC, New York (United States); Lamare, F. [INSERM U650, LaTIM, University Hospital Medical School, F 29609 Brest (France); Maigne, L. [Departement de Curietherapie-Radiotherapie, Centre Jean Perrin, F 63000 Clemont-Ferrand (France); Staelens, S. [UGent-ELIS, St-Pietersnieuwstraat, 41, B 9000 Gent (Belgium); Taschereau, R. [CRUMP Institute for Molecular Imaging, UCLA, Los Angeles (United States)

    2006-12-20

    One of the roles for Monte Carlo (MC) simulation studies is in the area of dosimetry. A number of different codes dedicated to dosimetry applications are available and widely used today, such as MCNP, EGSnrc and PTRAN. However, such codes do not easily facilitate the description of complicated 3D sources or emission tomography systems and associated data flow, which may be useful in different dosimetry application domains. Such problems can be overcome by the use of specific MC codes such as GATE (GEANT4 Application to Tomographic Emission), which is based on Geant4 libraries, providing a scripting interface with a number of advantages for the simulation of SPECT and PET systems. Despite this potential, its major disadvantage is in terms of efficiency involving long execution times for applications such as dosimetry. The strong points and disadvantages of GATE in comparison to other dosimetry specific codes are discussed and illustrated in terms of accuracy, efficiency and flexibility. A number of features, such as the use of voxelised and moving sources, as well as developments such as advanced visualization tools and the development of dose estimation maps allowing GATE to be used for dosimetry applications are presented. In addition, different examples from dosimetry applications with GATE are given. Finally, future directions with respect to the use of GATE for dosimetry applications are outlined.

  8. Die Ferse schmerzt: Behandlung des M. triceps surae bei Patienten mit Fasciitis plantaris : Ein systematisches Literaturreview

    OpenAIRE

    Brunner, Melanie

    2015-01-01

    Darstellung des Themas: Die Dehnung des M. triceps surae bei Patienten mit Fasciitis plantaris wird in der Literatur als begleitende Intervention empfohlen. Dies lässt einen Zusammenhang zwischen den Plantarflexoren und den Fersenschmerzen vermuten, weshalb die Untersuchung von weiteren Behandlungsmethoden am M. triceps surae von Bedeutung ist. Ziel: Das Ziel dieser Arbeit war, eine Aussage über die Effektivität von verschiedenen Behandlungsmethoden des M. triceps surae bei Patienten mit F...

  9. Kognitive Funktionen bei adoleszenten Patienten mit Anorexia nervosa und unipolaren Affektiven Störungen

    OpenAIRE

    Sarrar, Lea

    2014-01-01

    Anorexia nervosa und unipolare Affektive Störungen stellen häufige und schwerwiegende kinder- und jugendpsychiatrische Störungsbilder dar, deren Pathogenese bislang nicht vollständig entschlüsselt ist. Verschiedene Studien zeigen bei erwachsenen Patienten gravierende Auffälligkeiten in den kognitiven Funktionen. Dahingegen scheinen bei adoleszenten Patienten lediglich leichtere Einschränkungen in den kognitiven Funktionen vorzuliegen. Die Prävalenz der Anorexia nervosa und unipolaren Affektiv...

  10. Sandia National Laboratories Internal Dosimetry Technical Basis Manual (Rev 4)

    Energy Technology Data Exchange (ETDEWEB)

    Goke, Sarah Hayes [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Elliott, Nathan Ryan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2014-09-01

    The Sandia National Laboratories’ Internal Dosimetry Technical Basis Manual is intended to provide extended technical discussion and justification of the internal dosimetry program at SNL. It serves to record the approach to evaluating internal doses from radiobioassay data, and where appropriate, from workplace monitoring data per the Department of Energy Internal Dosimetry Program Guide DOE G 441.1C. The discussion contained herein is directed primarily to current and future SNL internal dosimetrists. In an effort to conserve space in the TBM and avoid duplication, it contains numerous references providing an entry point into the internal dosimetry literature relevant to this program. The TBM is not intended to act as a policy or procedure statement, but will supplement the information normally found in procedures or policy documents. The internal dosimetry program outlined in this manual is intended to meet the requirements of Federal Rule 10CFR835 for monitoring the workplace and for assessing internal radiation doses to workers.

  11. Research Article. Improved Dual Frequency PPP Model Using GPS and BeiDou Observations

    Directory of Open Access Journals (Sweden)

    Afifi A.

    2017-02-01

    Full Text Available This paper introduces a new dual-frequency precise point positioning (PPP model, which combines GPS and BeiDou observations. Combining GPS and BeiDou observations in a PPP model offers more visible satellites to the user, which is expected to enhance the satellite geometry and the overall PPP solution in comparison with GPSonly PPP solution. However, combining different GNSS constellations introduces additional biases, which require rigorous modelling, including GNSS time offset and hardware delays. In this research, ionosphere-free linear combination PPP model is developed. The additional biases, which result from combining the GPS and BeiDou observables, are lumped into a new unknown parameter identified as the inter-system bias. Natural Resources Canada’s GPSPace PPP software is modified to enable a combined GPS/BeiDou PPP solution and to handle the newly introduced biases. A total of four data sets at four IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the IGS-MGEX network are used to correct both of the GPS and BeiDou measurements. It is shown that a sub-decimeter positioning accuracy level and 25% reduction in the solution convergence time can be achieved with combining GPS and Bei-Dou observables in a PPP model, in comparison with the GPS-only PPP solution.

  12. BeiDou Inter-Satellite-Type Bias Evaluation and Calibration for Mixed Receiver Attitude Determination

    Directory of Open Access Journals (Sweden)

    Noor Raziq

    2013-07-01

    Full Text Available The Chinese BeiDou system (BDS, having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS. It consists of Geostationary Earth Orbit (GEO satellites, Inclined Geosynchronous Satellite Orbit (IGSO satellites and Medium Earth Orbit (MEO satellites. This paper investigates the receiver-dependent bias between these satellite types, for which we coined the name “inter-satellite-type bias” (ISTB, and its impact on mixed receiver attitude determination. Assuming different receiver types may have different delays/biases for different satellite types, we model the differential ISTBs among three BeiDou satellite types and investigate their existence and their impact on mixed receiver attitude determination. Our analyses using the real data sets from Curtin’s GNSS array consisting of different types of BeiDou enabled receivers and series of zero-baseline experiments with BeiDou-enabled receivers reveal the existence of non-zero ISTBs between different BeiDou satellite types. We then analyse the impact of these biases on BeiDou-only attitude determination using the constrained (C-LAMBDA method, which exploits the knowledge of baseline length. Results demonstrate that these biases could seriously affect the integer ambiguity resolution for attitude determination using mixed receiver types and that a priori correction of these biases will dramatically improve the success rate.

  13. Estimation of Satellite PCO Offsets for BeiDou based on MGEX Net Solution

    Science.gov (United States)

    Yize, Zhang; Junping, Chen; Bin, Wu; Jiexian, Wang

    2015-04-01

    BeiDou Satellite Navigation System currently has a total 14 satellites including GEO/IGSO/MEO satellites and providing a regional PNT service. Due to a lack of publicly available antenna phase center offsets (PCO) for the BeiDou satellites, conventional values of (+0.6 m, 0.0 m, +1.1 m) are recommended for orbit and clock determination of the GEO/IGSO/MEO satellites, which needs to be further estimation and refinement. In this paper, we propose a multi-GNSS network solution for the estimation of BeiDou satellite PCO. More than 35 ground stations of International GNSS MGEX tracking network are used to determine the BeiDou satellite PCO. In this strategy, the GPS and BeiDou satellite orbits and clocks are derived from IGS final products, and GPS satellite PCO and PCV are fixed according to igs08.atx. The BeiDou satellites PCO are estimated together with the station clock, troposphere delay and LC combination ambiguity parameter. Result shows that the RMS of phase residuals for all stations is 1.8cm and is 1.6m for code residual, respectively. The estimated PCO is different for each satellite. Appling the new PCO for precise point positioning, we found that the positioning error improves from 6cm to 2cm in height.

  14. Research Article. Improved Dual Frequency PPP Model Using GPS and BeiDou Observations

    Science.gov (United States)

    Afifi, A.; El-Rabbany, A.

    2017-02-01

    This paper introduces a new dual-frequency precise point positioning (PPP) model, which combines GPS and BeiDou observations. Combining GPS and BeiDou observations in a PPP model offers more visible satellites to the user, which is expected to enhance the satellite geometry and the overall PPP solution in comparison with GPSonly PPP solution. However, combining different GNSS constellations introduces additional biases, which require rigorous modelling, including GNSS time offset and hardware delays. In this research, ionosphere-free linear combination PPP model is developed. The additional biases, which result from combining the GPS and BeiDou observables, are lumped into a new unknown parameter identified as the inter-system bias. Natural Resources Canada's GPSPace PPP software is modified to enable a combined GPS/BeiDou PPP solution and to handle the newly introduced biases. A total of four data sets at four IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the IGS-MGEX network are used to correct both of the GPS and BeiDou measurements. It is shown that a sub-decimeter positioning accuracy level and 25% reduction in the solution convergence time can be achieved with combining GPS and Bei-Dou observables in a PPP model, in comparison with the GPS-only PPP solution.

  15. Fondaparinux bei Herz-Kreislauf-Erkrankungen: Ein neues Antithrombin mit herausragenden Eigenschaften

    Directory of Open Access Journals (Sweden)

    Huber K

    2008-01-01

    Full Text Available Fondaparinux, ein synthetisches Pentasaccharid, führt zu einer indirekten Hemmung des Gerinnungsfaktors Xa und behindert in der Folge die Bildung von Thrombin. Fondaparinux wurde als Vergleichssubstanz gegenüber unfraktioniertem (Standard- Heparin oder dem niedermolekularen Heparin Enoxaparin in der Prophylaxe oder Therapie von venösen Thrombosen getestet. Zuletzt wurde Fondaparinux auch bei Patienten mit akuten Koronarsyndromen (ACS untersucht: bei Patienten mit ACS ohne ST-Hebung (NSTE-ACS waren sowohl die Blutungsrate als auch die Kurz- und Langzeitmortalität im Fondaparinuxarm (2,5 mg/Tag s. c. signifikant geringer als in den Enoxaparin-behandelten Patienten (1 mg/kg KG 2×/Tag s. c. (OASIS-5-Studie. Bei Patienten mit akutem ST-Strecken-Hebungsinfarkt (STEMI war Fondaparinux in den Subgruppen der konservativ behandelten Patienten (ohne Reperfusion und der Patienten, die eine pharmakologische Reperfusion erhielten (Thrombolyse von Vorteil gegenüber Placebo oder unfraktioniertem Heparin. Hingegen zeigte sich bei Patienten mit STEMI, die einer Akut-PCI unterzogen wurden, eine starke Tendenz zugunsten von unfraktioniertem Heparin gegenüber Fondaparinux (OASIS-6-Studie. Daher wird Fondaparinux in den internationalen Richtlinien als das Antithrombin mit der günstigsten Risiko/Nutzen-Ratio bei NSTEMI aber auch bei STEMI-Patienten mit Ausnahme jener Patienten, die sich einer Akut-PCI unterziehen, empfohlen. Fondaparinux könnte schon in der nahen Zukunft die Heparine in diesen Indikationen weitgehend ersetzen.

  16. Neutron dosimetry for low dose rate Cf-252 AT sources and adherence to recent clinical dosimetry protocol for brachytherapy

    Energy Technology Data Exchange (ETDEWEB)

    Rivard, M.J.; Wierzbicki, J.G.; Van den Heuvel, F. [Wayne State Univ., Detroit, MI (United States). Dept. of Radiation Oncology; Martin, R.C. [Oak Ridge National Lab., TN (United States). Chemical Technology Div.

    1997-12-01

    In 1995, the American Association of Physicists in Medicine Task Group 43 (AAPM TG-43) published a protocol obsoleting all mixed-field radiation dosimetry for Cf-252. Recommendations for a new brachytherapy dosimetry formalism made by this Task Group favor quantification of source strength in terms of air kerma rather than apparent Curies or other radiation units. Additionally, representation of this dosimetry data in terms of radial dose functions, anisotropy functions, geometric factors, and dose rate constants are in an angular and radial (spherical) coordinate system as recommended, rather than the along-away dosimetry data (Cartesian coordinate system) currently available. This paper presents the initial results of calculated neutron dosimetry in a water phantom for a Cf-252 applicator tube (AT) type medical source soon available from Oak Ridge National Laboratory (ORNL).

  17. Dosimetry applications in GATE Monte Carlo toolkit.

    Science.gov (United States)

    Papadimitroulas, Panagiotis

    2017-02-21

    Monte Carlo (MC) simulations are a well-established method for studying physical processes in medical physics. The purpose of this review is to present GATE dosimetry applications on diagnostic and therapeutic simulated protocols. There is a significant need for accurate quantification of the absorbed dose in several specific applications such as preclinical and pediatric studies. GATE is an open-source MC toolkit for simulating imaging, radiotherapy (RT) and dosimetry applications in a user-friendly environment, which is well validated and widely accepted by the scientific community. In RT applications, during treatment planning, it is essential to accurately assess the deposited energy and the absorbed dose per tissue/organ of interest, as well as the local statistical uncertainty. Several types of realistic dosimetric applications are described including: molecular imaging, radio-immunotherapy, radiotherapy and brachytherapy. GATE has been efficiently used in several applications, such as Dose Point Kernels, S-values, Brachytherapy parameters, and has been compared against various MC codes which are considered as standard tools for decades. Furthermore, the presented studies show reliable modeling of particle beams when comparing experimental with simulated data. Examples of different dosimetric protocols are reported for individualized dosimetry and simulations combining imaging and therapy dose monitoring, with the use of modern computational phantoms. Personalization of medical protocols can be achieved by combining GATE MC simulations with anthropomorphic computational models and clinical anatomical data. This is a review study, covering several dosimetric applications of GATE, and the different tools used for modeling realistic clinical acquisitions with accurate dose assessment. Copyright © 2017 Associazione Italiana di Fisica Medica. Published by Elsevier Ltd. All rights reserved.

  18. Retrospective accident dosimetry using trapped charges

    Energy Technology Data Exchange (ETDEWEB)

    Lee, J. I.; Kim, J. L.; Chang, I.; Kim, B. H. [Korea Atomic Energy Research Institute, Daejeon (Korea, Republic of)

    2015-10-15

    Dicentric chromosome aberrations technique scoring of aberrations in metaphases prepared from human lymphocytes is most commonly used. This is considered as a reliable technique because the sample is extracted from the individual human body itself. There are other techniques in biological dosimetry such as Fluorescence In Situ Hybridization (FISH) using translocations, premature chromosome condensation (PCC) and micronucleus assay. However the minimum detectable doses (MDD) are relatively high and sample preparation time is also relatively longer. Therefore, there is limitation in use of these techniques for the purpose of triage in a short time in case of emergency situation relating large number of persons. Electronic paramagnetic resonance (EPR) technique is based on the signal from unpaired electrons such as free radicals in irradiated materials especially tooth enamel, however it has also limitation for the purpose of triage because of difficulty of sample taking and its high MDD. Recently as physical methods, thermoluminescence (TL) and optically stimulated luminescence (OSL) technique have been attracted due to its lower MDD and simplicity of sample preparation. Density of the trapped charges is generally proportional to the radiation dose absorbed and the intensity of emitting light is also proportional to the density of trapped charges, thus it can be applied to measure radiation dose retrospectively. In this presentation, TL and OSL techniques are going to introduced and discussed as physical methods for retrospective accident dosimetry using trapped charges especially in electronic component materials. As a tool for dose reconstruction for emergency situation, thermoluminescece and optically stimulated luminescence techniques which are based on trapped charges during exposure of material are introduced. These techniques have several advantages such as high sensitivity, fast evaluation and ease to sample collection over common biological dosimetry and EPR

  19. In vivo light dosimetry for pleural PDT

    Science.gov (United States)

    Dimofte, Andreea; Zhu, Timothy C.; Finlay, Jarod C.; Culligan, Melissa; Edmonds, Christine E.; Friedberg, Joseph S.; Cengel, Keith; Hahn, Stephen M.

    2009-02-01

    In-vivo light Dosimetry for patients undergoing photodynamic therapy (PDT) is one of the important dosimetry quantities critical for predicting PDT outcome. This study examines the light fluence (rate) delivered to patients undergoing pleural PDT as a function of treatment time, treatment volume and surface area, and its accuracy as a function of the calibration accuracies of each isotropic detector and the calibration integrating sphere. The patients studied here were enrolled in Phase II clinical trial of Photofrin-mediated PDT for the treatment of non-small cell lung cancer with pleural effusion. The ages of the patients studied varied from 34 to 69 year old. All patients were administered 2mg per kg body weight Photoprin 24 hours before the surgery. Patients undergoing photodynamic therapy (PDT) are treated with laser light with a light fluence of 60 J/cm^2 at 630nm. Fluence rate (mW/cm^2) and cumulative fluence (J/cm^2) was monitored at 7 different sites during the entire light treatment delivery. Isotropic detectors were used for in-vivo light dosimetry. The anisotropy of each isotropic detector was found to be within 30%. The mean fluence rate delivery varied from 37.84 to 94.05 mW/cm^2 and treatment time varied from 1762 to 5232s. We have established a correlation between the treatment time and the treatment volume. The results are discussed using an integrating sphere theory and the measured tissue optical properties. The result can be used as a clinical guideline for future pleural PDT treatment.

  20. Kontrastmittelverstärkte Magnet-Resonanz-Urographie unter forcierter Diurese - Stellenwert in der Differentialdiagnostik bei Obstruktionen des oberen Harntraktes

    Directory of Open Access Journals (Sweden)

    Jung P

    2001-01-01

    Full Text Available Die Magnet-Resonanz-Urographie (MRU ist ein relativ neues Verfahren in der Diagnostik des oberen Harntraktes. Das Ziel dieser Studie war der Vergleich der Aussagefähigkeit der MRU unter Gabe von Gadolinium und Furosemid und dem konventionellen Urogramm (IVU in der Diagnostik der Ursache von Obstruktionen im Bereich des Harnleiters. 82 Patienten mit im IVU nachgewiesener Obstruktion des oberen Harntraktes oder urographisch stummer Niere bei sonographisch nachgewiesener Dilatation wurden der MRU zugeführt. Die Bilder beider Untersuchungsmethoden wurden von voneinander unabhängigen Untersuchern befundet. Zwei Urologen befundeten die IVU-Bilder, zwei Radiologen die MRU-Bilder, die Radiologen kannten die IVU-Diagnose nicht. Bei unklarer Diagnose wurden weitere Untersuchungen wie Computertomographie, retrograde Pyelographie oder Ureteroskopie durchgeführt. Die Diagnosen waren: Harnleitersteine bei 72 Patienten, Harnleitertumore bei 8 Patienten und extraureterale Tumore bei 2 Patienten. Eine richtige Diagnose bei den Steinpatienten wurde durch IVU bei 49 von 72 Patienten und durch MRU bei 64 von 72 Patienten gestellt. In dieser Patientengruppe wurden durch die MRU zwei falsche Diagnosen gestellt. Fehlende Kontrastmittelausscheidung war der Hauptgrund für Versagen der IVU. 3 der 8 Patienten mit Harnleitertumoren wurden durch die IVU richtig dignostiziert, bei dreien wurde eine falsche Diagnose gestellt. Durch die MRU konnten in dieser Gruppe 7 von 8 Patienten korrekt diagnostiziert werden, es wurde keine falsche Diagnose erhoben. IVU wird zunächst die Standarduntersuchungstechnik zur Darstellung des oberen Harntraktes bleiben, aber durch diese Studie konnte die Möglichkeit gezeigt werden, die in der MRU in Kombination mit Gadolinium und Furosemid liegt. Die größte Bedeutung dieser Untersuchung liegt in der urographisch stummen Niere, bei Untersuchungen in der Schwangerschaft, bei Kindern und bei Patienten mit Kontrastmittelunverträglichkeit.

  1. Neutron spectrometry and dosimetry with ANNs

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H. R.; Hernandez D, V. M. [Unidad Academica de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 10, Fracc. La Penuela, 98068 Zacatecas (Mexico); Gallego, E.; Lorente, A. [Departamento de Ingenieria Nuclear, Universidad Politecnica de Madrid, Jose Gutierrez Abascal 2, 28006 Madrid (Spain)], e-mail: fermineutron@yahoo.com

    2009-10-15

    Artificial neural networks technology has been applied to unfold the neutron spectra and to calculate the effective dose, the ambient equivalent dose, and the personal dose equivalent for {sup 252}Cf and {sup 241}AmBe neutron sources. A Bonner sphere spectrometry with a {sup 6}LiI(Eu) scintillator was utilized to measure the count rates of the spheres that were utilized as input in two artificial neural networks, one for spectrometry and another for dosimetry. Spectra and the ambient dose equivalent were also obtained with BUNKIUT code and the UTA4 response matrix. With both procedures spectra and ambient dose equivalent agrees in less than 10%. (author)

  2. Secondary standard dosimetry laboratory at INFLPR

    Energy Technology Data Exchange (ETDEWEB)

    Scarlat, F.; Minea, R.; Scarisoreanu, A.; Badita, E.; Sima, E.; Dumitrascu, M.; Stancu, E.; Vancea, C., E-mail: scarlat.f@gmail.com [National Institute for Laser, Plasma and Radiation Physics - INFLPR, Bucharest (Romania)

    2011-07-01

    National Institute for Laser, Plasma and Radiation Physics (INFLPR) has constructed a High Energy Secondary Standard Dosimetry Laboratory SSDL-STARDOOR - for performing dosimetric calibrations according to ISO IEC SR/EN 17025:2005 standards. This is outfitted with UNIDOS Secondary Standard Dosimeter from PTW (Freiburg Physikalisch-Technische Werksttaten) calibrated at the PTB-Braunschweig (German Federal Institute of Physics and Metrology). A radiation beam of the quality of Q used by our laboratory as calibration source are provided by INFLPR 7 MeV electron beam linear accelerator mounted in our facility. (author)

  3. Eurados trial performance test for photon dosimetry

    DEFF Research Database (Denmark)

    Stadtmann, H.; Bordy, J.M.; Ambrosi, P.

    2001-01-01

    Within the framework of the EURADOS Action entitled Harmonisation and Dosimetric Quality Assurance in Individual Monitoring for External Radiation, trial performance tests for whole-body and extremity personal dosemeters were carried out. Photon, beta and neutron dosemeters were considered....... This paper summarises the results of the whole-body photon dosemeter test. Twenty-six dosimetry services from all EU Member States and Switzerland participated. Twelve different radiation fields were used to simulate various workplace irradiation fields. Dose values from 0.4 mSv to 80 mSv were chosen. From...

  4. Proton minibeam radiation therapy: Experimental dosimetry evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Peucelle, C.; Martínez-Rovira, I.; Prezado, Y., E-mail: prezado@imnc.in2p3.fr [IMNC-UMR 8165, CNRS, Paris 7 and Paris 11 Universities, 15 rue Georges Clemenceau, Orsay Cedex 91406 (France); Nauraye, C.; Patriarca, A.; Hierso, E.; Fournier-Bidoz, N. [Institut Curie - Centre de Protonthérapie d’Orsay, Campus Universitaire, Bât. 101, Orsay 91898 (France)

    2015-12-15

    Purpose: Proton minibeam radiation therapy (pMBRT) is a new radiotherapy (RT) approach that allies the inherent physical advantages of protons with the normal tissue preservation observed when irradiated with submillimetric spatially fractionated beams. This dosimetry work aims at demonstrating the feasibility of the technical implementation of pMBRT. This has been performed at the Institut Curie - Proton Therapy Center in Orsay. Methods: Proton minibeams (400 and 700 μm-width) were generated by means of a brass multislit collimator. Center-to-center distances between consecutive beams of 3200 and 3500 μm, respectively, were employed. The (passive scattered) beam energy was 100 MeV corresponding to a range of 7.7 cm water equivalent. Absolute dosimetry was performed with a thimble ionization chamber (IBA CC13) in a water tank. Relative dosimetry was carried out irradiating radiochromic films interspersed in a IBA RW3 slab phantom. Depth dose curves and lateral profiles at different depths were evaluated. Peak-to-valley dose ratios (PVDR), beam widths, and output factors were also assessed as a function of depth. Results: A pattern of peaks and valleys was maintained in the transverse direction with PVDR values decreasing as a function of depth until 6.7 cm. From that depth, the transverse dose profiles became homogeneous due to multiple Coulomb scattering. Peak-to-valley dose ratio values extended from 8.2 ± 0.5 at the phantom surface to 1.08 ± 0.06 at the Bragg peak. This was the first time that dosimetry in such small proton field sizes was performed. Despite the challenge, a complete set of dosimetric data needed to guide the first biological experiments was achieved. Conclusions: pMBRT is a novel strategy in order to reduce the side effects of RT. This works provides the experimental proof of concept of this new RT method: clinical proton beams might allow depositing a (high) uniform dose in a brain tumor located in the center of the brain (7.5 cm depth

  5. Characterization of brazilian wollastonite for radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Souza, D.N. [Departamento de Fisica, Universidade Federal de Sergipe, Sao Cristovao/SE (Brazil); Melo, A.P.; Gazano, V.S.O.; Caldas, L.V.E. [Instituto de Pesquisas Energeticas e Nucleares, Comissao Nacional de Energia Nuclear, Sao Paulo (Brazil)]. e-mail: dnsouza@fisca.ufs.br

    2006-07-01

    In these work preliminary results of the characterization analyses of Brazilian Wollastonite for radiation dosimetry are presented. Wollastonite is a silicate of calcium, Ca(SiO{sub 3}), and it was acquired in the form of rude mineral with Andradite inclusions. The sample was cleaned and prepared for obtained selected grains of Wollastonite. The analyses of chemical and mineralogical compositions were obtained using the neutron activation and X-ray powder diffraction techniques. The thermoluminescent (TL) glow curve of the material shows a prominent peak at about 200 C. TL emission spectra, and photoinduced emission spectra were also obtained. (Author)

  6. Calculation and Analysis of Differential Corrections for BeiDou

    Science.gov (United States)

    Yang, Sainan; Chen, Junping; Zhang, Yize

    2015-04-01

    BeiDou Satellite Navigation System has been providing service forAsia-Pacific area. BeiDou uses observations of regional monitoring network to determine satellite orbit, which limits the satellite orbit accuracy. And the satellite clock error is produced by time synchronization system. The time synchronization delay of antenna device is general obtained through prior Calibration, and the residual calibration error is included in the satellite clock, which affects the prediction accuracy of satellite clock error. In this paper, we study the algorithms of Beidou differential corrections to improve the accuracy of satellite signals to improve the user positioning accuracy. In this algorithm, both pseudo-range and phase observations are used to calculate differential corrections. We process pseudo-range observations to obtain equivalent satellite clock error, which include satellite clock errors and orbit radial errors, as well as the average projection of orbit tangential and normal errors in combination. And the epoch-difference of phase observations are processed to eliminate the ambiguity which simplifies algorithms and ensure the relative accuracy (corrections variety between the epochs). Observations more than 10 stations in China are processed, and the equivalent clock error calculation results are analyzed, which shows that the satellite UDRE are significantly reduced and user location accuracy improves when the equivalent clock error corrections are applied. The residuals deducting equivalent satellite clock error contains the projection difference of satellite orbit error in all station (tangential and normal errors are main). We utilize the residuals to solve the tangential and normal orbit errors which cause the projection difference. The same observation data is processed. The results show that after calculating three-dimensional corrections, the satellite UDRE doesn't improve significantly compared to equivalent satellite clock error corrections and user

  7. Dosimetry of ionising radiation in modern radiation oncology

    Science.gov (United States)

    Kron, Tomas; Lehmann, Joerg; Greer, Peter B.

    2016-07-01

    Dosimetry of ionising radiation is a well-established and mature branch of physical sciences with many applications in medicine and biology. In particular radiotherapy relies on dosimetry for optimisation of cancer treatment and avoidance of severe toxicity for patients. Several novel developments in radiotherapy have introduced new challenges for dosimetry with small and dynamically changing radiation fields being central to many of these applications such as stereotactic ablative body radiotherapy and intensity modulated radiation therapy. There is also an increasing awareness of low doses given to structures not in the target region and the associated risk of secondary cancer induction. Here accurate dosimetry is important not only for treatment optimisation but also for the generation of data that can inform radiation protection approaches in the future. The article introduces some of the challenges and highlights the interdependence of dosimetric calculations and measurements. Dosimetric concepts are explored in the context of six application fields: reference dosimetry, small fields, low dose out of field, in vivo dosimetry, brachytherapy and auditing of radiotherapy practice. Recent developments of dosimeters that can be used for these purposes are discussed using spatial resolution and number of dimensions for measurement as sorting criteria. While dosimetry is ever evolving to address the needs of advancing applications of radiation in medicine two fundamental issues remain: the accuracy of the measurement from a scientific perspective and the importance to link the measurement to a clinically relevant question. This review aims to provide an update on both of these.

  8. Monte Carlo simulations for heavy ion dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Geithner, O.

    2006-07-26

    Water-to-air stopping power ratio (s{sub w,air}) calculations for the ionization chamber dosimetry of clinically relevant ion beams with initial energies from 50 to 450 MeV/u have been performed using the Monte Carlo technique. To simulate the transport of a particle in water the computer code SHIELD-HIT v2 was used which is a substantially modified version of its predecessor SHIELD-HIT v1. The code was partially rewritten, replacing formerly used single precision variables with double precision variables. The lowest particle transport specific energy was decreased from 1 MeV/u down to 10 keV/u by modifying the Bethe- Bloch formula, thus widening its range for medical dosimetry applications. Optional MSTAR and ICRU-73 stopping power data were included. The fragmentation model was verified using all available experimental data and some parameters were adjusted. The present code version shows excellent agreement with experimental data. Additional to the calculations of stopping power ratios, s{sub w,air}, the influence of fragments and I-values on s{sub w,air} for carbon ion beams was investigated. The value of s{sub w,air} deviates as much as 2.3% at the Bragg peak from the recommended by TRS-398 constant value of 1.130 for an energy of 50 MeV/u. (orig.)

  9. Dosimetry of radium-223 and progeny

    Energy Technology Data Exchange (ETDEWEB)

    Fisher, D.R. [Pacific Northwest National Lab., Richland, WA (United States); Sgouros, G. [Memorial Sloan-Kettering Cancer Center, New York, NY (United States)

    1999-01-01

    Radium-223 is a short-lived (11.4 d) alpha emitter with potential applications in radioimmunotherapy of cancer. Radium-223 can be complexed and linked to protein delivery molecules for specific tumor-cell targeting. It decays through a cascade of short-lived alpha- and beta-emitting daughters with emission of about 28 MeV of energy through complete decay. The first three alpha particles are essentially instantaneous. Photons associated with Ra-223 and progeny provide the means for tumor and normal-organ imaging and dosimetry. Two beta particles provide additional therapeutic value. Radium-223 may be produced economically and in sufficient amounts for widescale application. Many aspects of the chemistry of carrier-free isotope preparation, complexation, and linkage to the antibody have been developed and are being tested. The radiation dosimetry of a Ra-223-labeled antibody shows favorable tumor to normal tissue dose ratios for therapy. The 11.4-d half-life of Ra-223 allows sufficient time for immunoconjugate preparation, administration, and tumor localization by carrier antibodies before significant radiological decay takes place. If 0.01 percent of a 37 MBq (1 mCi) injection deposits in a one gram tumor mass, and if the activity is retained with a typical effective half-time (75 h), the absorbed dose will be 163 mGy MBq{sup {minus}1} (600 rad mCi{sup {minus}1}) administered. 49 refs., 5 figs., 2 tabs.

  10. Eleventh DOE workshop on personnel neutron dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    1991-12-31

    Since its formation, the Office of Health (EH-40) has stressed the importance of the exchange of information related to and improvements in neutron dosimetry. This Workshop was the eleventh in the series sponsored by the Department of Energy (DOE). It provided a forum for operational personnel at DOE facilities to discuss current issues related to neutron dosimetry and for leading investigators in the field to discuss promising approaches for future research. A total of 26 papers were presented including the keynote address by Dr. Warren K. Sinclair, who spoke on, ``The 1990 Recommendations of the ICRP and their Biological Background.`` The first several papers discussed difficulties in measuring neutrons of different energies and ways of compensating or deriving correction factors at individual facilities. Presentations were also given by the US Navy and Air Force. Current research in neutron dosimeter development was the subject of the largest number of papers. These included a number on the development of neutron spectrometers. Selected papers were processed separately for inclusion in the Energy Science and Technology Database.

  11. DRDC Ottawa working standard for biological dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Segura, T.M.; Prud' homme-Lalonde, L. [Defence Research and Development Canada, Ottawa, Ontario (Canada); Thorleifson, E. [Health Canada, Gatineau, Quebec (Canada); Lachapelle, S.; Mullins, D. [JERA Consulting (Canada); Qutob, S. [Health Canada, Gatineau, Quebec (Canada); Wilkinson, D.

    2005-07-15

    This Standard provides quality assurance, quality control, and evaluation of the performance criteria for the purpose of accreditation of the Radiation Biology laboratory at Defence Research and Development Canada - Ottawa (DRDC Ottawa) using biological dosimetry to predict radiation exposure doses. The International Standard (ISO 19238) and the International Atomic Energy Association (IAEA) Technical Report Series No. 405 are used as guiding documents in preparation of this working document specific to the DRDC Ottawa Radiation Biology Laboratory. This Standard addresses: 1. The confidentiality of personal information, for the customer and the service laboratory; 2. The laboratory safety requirements; 3. The calibration sources and calibration dose ranges useful for establishing the reference dose-effect curves allowing the dose estimation from chromosome aberration frequency, and the minimum detection levels; 4. Transportation criteria for shipping of test samples to the laboratory; 5. Preparation of samples for analysis; 6. The scoring procedure for unstable chromosome aberrations used for biological dosimetry; 7. The criteria for converting a measured aberration frequency into an estimate of absorbed dose; 8. The reporting of results; 9. The quality assurance and quality control plan for the laboratory; and 10. Informative annexes containing examples of a questionnaire, instructions for customers, a data sheet for recording aberrations, a sample report and other supportive documents. (author)

  12. Dosimetry methods in boron neutron capture therapy

    Energy Technology Data Exchange (ETDEWEB)

    Gambarini, G.; Artuso, E.; Felisi, M.; Regazzoni, V.; Giove, D. [Universita degli Studi di Milano, Department of Physics, Via Festa del Patrono 7, 20122 Milano (Italy); Agosteo, S.; Barcaglioni, L. [Istituto Nazionale di Fisica Nucleare, Milano (Italy); Campi, F.; Garlati, L. [Politecnico di Milano, Energy Department, Piazza Leonardo Da Vinci 32, 20133 Milano (Italy); De Errico, F. [Universita degli Studi di Pisa, Department of Civil and Industrial Engineering, Lungamo Pacinotti 43, 56126 Pisa (Italy); Borroni, M.; Carrara, M. [Fondazione IRCCS Istituto Nazionale Tumori, Medical Physics Unit, Via Venezian 1, 20133 Milano (Italy); Burian, J.; Klupak, V.; Viererbl, L.; Marek, M. [Research Centre Rez, Department of Neutron Physics, 250-68 Husinec-Rez (Czech Republic)

    2014-08-15

    Dosimetry studies have been carried out at thermal and epithermal columns of Lvr-15 research reactor for investigating the spatial distribution of gamma dose, fast neutron dose and thermal neutron fluence. Two different dosimetry methods, both based on solid state detectors, have been studied and applied and the accuracy and consistency of the results have been inspected. One method is based on Fricke gel dosimeters that are dilute water solutions and have good tissue equivalence for neutrons and also for all the secondary radiations produced by neutron interactions in tissue or water phantoms. Fricke gel dosimeters give the possibility of separating the various dose contributions, i.e. the gamma dose, the fast neutron dose and the dose due to charged particles generated during thermal neutron reactions by isotopes having high cross section, like 10-B. From this last dose, thermal neutron fluence can be obtained by means of the kerma factor. The second method is based on thermoluminescence dosimeters. In particular, the developed method draw advantage from the different heights of the peaks of the glow curve of such phosphors when irradiated with photons or with thermal neutrons. The results show that satisfactory results can be obtained with simple methods, in spite of the complexity of the subject. However, the more suitable dosimeters and principally their utilization and analysis modalities are different for the various neutron beams, mainly depending on the relative intensities of the three components of the neutron field, in particular are different for thermal and epithermal columns. (Author)

  13. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2009-08-28

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program (HEDP) which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee (HPDAC) which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving changes to all chapters in the document. Revision numbers that include a decimal fraction reflect minor revisions, usually restricted to selected chapters or selected pages in the document.

  14. Radiation Dosimetry for Quality Control of Food Preservation and Disinfestation

    DEFF Research Database (Denmark)

    McLaughlin, W.L.; Miller, Arne; Uribe, R.M.

    1983-01-01

    In the use of x and gamma rays and scanned electron beams to extend the shelf life of food by delay of sprouting and ripening, killing of microbes, and control of insect population, quality assurance is provided by standardized radiation dosimetry. By strategic placement of calibrated dosimeters...... speed) to meet changes that occur in product and source parameters (e.g. bulk density and radiation spectrum). Routine dosimetry methods and certain corrections of dosimetry data may be selected for the radiations used in typical food processes....

  15. Dosimetry of Auger emitters: Physical and phenomenological approaches

    Energy Technology Data Exchange (ETDEWEB)

    Sastry, K.S.R.; Howell, R.W.; Rao, D.V.; Mylavarapu, V.B.; Kassis, A.I.; Adelstein, S.J.; Wright, H.A.; Hamm, R.N.; Turner, J.E.

    1987-01-01

    Recent radiobiological studies have demonstrated that Auger cascades can cause severe biological damage contrary to expectations based on conventional dosimetry. Several determinants govern these effects, including the nature of the Auger electron spectrum; localized energy deposition; cellular geometry; chemical form of the carrier; cellular localization, concentration, and subcellular distribution of the radionuclide. Conventional dosimetry is inadequate in that these considerations are ignored. Our results provide the basis for biophysical approaches toward subcellular dosimetry of Auger emitters in vitro and in vivo. 12 refs., 7 figs., 2 tabs.

  16. Dosimetry in clinical static magnetic fields using plastic scintillation detectors

    DEFF Research Database (Denmark)

    Stefanowicz, S.; Latzel, H.; Lindvold, Lars René

    2013-01-01

    , however, not clear yet how dosimetry will be conducted as standard methods and might not be easily transferred to systems with clinical magnetic fields. For dosimetry in MRI accelerators, we have tested plastic scintillation detectors (PSD) coupled to optical fibers. They are suitable for real-time and in......-vivo dosimetry in radiation treatments and diagnostics and could be, being all-optical, promising candidates for this application. To study the basic feasibility of using PSDs with organic scintillators in magnetic fields, we measured the response of these dosimeters in presence of magnetic fields up to 1 T...

  17. Adipositas bei Kindern: Elterliche Rechte, Paternalismus und Gerechtigkeit

    Directory of Open Access Journals (Sweden)

    Giesinger Johannes

    2015-07-01

    Full Text Available Am Beispiel von Adipositas (Fettleibigkeit werden in diesem Beitrag die Konflikte diskutiert, die zwischen elterlichen Rechten und den aus Gerechtigkeitserwägungen erwachsenden Ansprüchen von Kindern entstehen können. Es wird angenommen, dass Kinder Anspruch auf Gesundheit haben, und dass Adipositas sie in ihrer Gesundheit gefährdet. Die Frage lautet, was zu tun ist, wenn das Handeln der Eltern die Entstehung von Adipositas begünstigt. Es werden drei verschiedene Konzeptionen elterlicher Rechte diskutiert. Nach der ersten Konzeption sind elterliche Rechte in den Interessen oder Freiheiten der Eltern fundiert. Gemäß der zweiten Auffassung ergeben sich elterliche Rechte aus elterlichen Pflichten, während der dritte Ansatz die Bedeutung sogenannter Beziehungsgüter hervorhebt. Vor diesem Hintergrund werden zwei Thesen vertreten: Die erste lautet, dass Eltern nicht berechtigt sind, ihre Kinder in einer Weise aufzuziehen, die zu Adipositas führt. Die zweite These ist, dass es trotzdem gute Gründe für Zurückhaltung bei Eingriffen in die Familie gibt.

  18. A vendor`s cost management; Kostenmanagement bei einem Hersteller

    Energy Technology Data Exchange (ETDEWEB)

    Schomer, E. [Siemens AG, Erlangen (Germany). Energieerzeugung (KWU)

    1997-12-01

    The cost base of a company, its ability to innovate, and its customer orientedness are important, distinctive competencies and capabilities in the competition for tomorrow`s markets and contracts. The `top` program implemented throughout the Siemens company serves to strengthen competitiveness and generate a considerable increase in profits. In order to achieve these objectives, the program addresses productivity, innovation, and growth as strategic elements. A thorough, multifaceted change in corporate culture is considered a precondition. This concept encompasses both purely technical and scientific improvements and the increasingly more important non-technical regeneration of business processes. Only a quantum leap in productivity will allow the company to continue to exist in the future. (orig.) [Deutsch] Im Wettbewerb um die Maerkte und Geschaefte von morgen sind die Kostenbasis des Unternehmens, seine Innovationsfaehigkeit und Kundenorientierung wesentliche differenzierende Kompetenzen und Faehigkeiten. Ziele des im gesamten Hause Siemens laufenden Programmes unter dem Titel `top` sind die Staerkung der Wettbewerbskraft sowie eine nachhaltige Ertragssteigerung. Um diese zu erreichen, setzt das Programm bei den strategischen Elementen Produktivitaet, Innovation und Wachstum an, wobei eine umfassende und vielfaeltige Veraenderung der Unternehmenskultur Voraussetzung ist. Dabei werden unter diesem Begriff sowie die rein technisch-wissenschaftlichen Verbesserungen als auch die immer wichtiger gewordenen nicht-technischen Erneuerungen in den Geschaeftsprozessen verstanden. Nur durch einen Quantensprung in der Produktivitaet kann das Unternehmen in der Zukunft bestehen. (orig.)

  19. Gas hydrates in gas storage caverns; Gashydrate bei der Gaskavernenspeicherung

    Energy Technology Data Exchange (ETDEWEB)

    Groenefeld, P. [Kavernen Bau- und Betriebs-GmbH, Hannover (Germany)

    1997-12-31

    Given appropriate pressure and temperature conditions the storage of natural gas in salt caverns can lead to the formation of gas hydrates in the producing well or aboveground operating facilities. This is attributable to the stored gas becoming more or less saturated with water vapour. The present contribution describes the humidity, pressure, and temperature conditions conducive to gas hydrate formation. It also deals with the reduction of the gas removal capacity resulting from gas hydrate formation, and possible measures for preventing hydrate formation such as injection of glycol, the reduction of water vapour absorption from the cavern sump, and dewatering of the cavern sump. (MSK) [Deutsch] Bei der Speicherung von Erdgas in Salzkavernen kann es unter entsprechenden Druck- und Temperaturverhaeltnissen zur Gashydratbildung in den Foerdersonden oder obertaegigen Betriebseinrichtungen kommen, weil sich das eingelagerte Gas mehr oder weniger mit Wasserdampf aufsaettigt. Im Folgenden werden die Feuchtigkeits-, Druck- und Temperaturbedingungen, die zur Hydratbildung fuehren erlaeutert. Ebenso werden die Verringerung der Auslagerungskapazitaet durch die Hydratbildung, Massnahmen zur Verhinderung der Hydratbildung wie die Injektion von Glykol, die Verringerung der Wasserdampfaufnahme aus dem Kavernensumpf und die Entwaesserung der Kavernensumpfs selbst beschrieben.

  20. Ecological valuation of mechanic-biological waste treatment and waste combustion on the basis of energy balances and air pollutant balances; Oekologische Bewertung der mechanisch-biologischen Restabfallbehandlung und der Muellverbrennung auf Basis von Energie- und Schadgasbilanzen

    Energy Technology Data Exchange (ETDEWEB)

    Wallmann, R.

    1999-04-01

    The work aims at an ecological valuation of air pollutant emissions and energy consumption as particularly relevant aspects of waste treatment and waste combustion plants, based on new scientific results, in order to draw up ecological budgets and make system comparisons in waste treatment. The target set is particularly effectively achieved by the following: documentation and scientific derivation of relevant boundary conditions, careful surveying and data processing for the purpose of making up an ecological budget, and objective valuation and interpretation of results. The high transparency of the methodics should be emphasized. They make the results obtained conclusive and verifiable. (orig.) [Deutsch] Ziel der vorliegenden Arbeit ist die oekologische Bewertung der besonders relevanten Aspekte Abluftemissionen und Energieverbrauch von MBA und MVA auf Basis aktueller Forschungsergebnisse als Grundlage fuer Oekobilanzen und Systemvergleiche zur Restabfallbehandlung. Diese Zielvorgabe wird durch die Dokumentation und wissenschaftliche Herleitung relevanter Rahmenbedingungen, sorgfaeltige Erhebung und Aufbereitung der Daten unter Gesichtspunkten der Erstellung einer Oekobilanz und letztendlich aufgrund der objektiven Bewertung und Interpretation der Ergebnisse im besonderen Masse erreicht. Besonders hervorzuheben hierbei ist die hohe Transparenz bei der methodischen Vorgehensweise. Die ermittelten Ergebnisse sind somit nachvollziehbar und ueberpruefbar. (orig.)

  1. Soil Moisture Retrieval Using Reflected Signals of BeiDou GEO Satellites

    Directory of Open Access Journals (Sweden)

    ZOU Wenbo

    2016-02-01

    Full Text Available This paper proposes a method of continuous long-term soil moisture measurement using signals from BeiDou GEO satellites. It also presents the soil moisture inversion model as well as the relevant signal processing steps. Moreover, a land-based experiment is carried out to verify its validity. This method adopts the dual-antenna Global Navigation Satellite System Reflection (GNSS-R mode to receive and process direct signal from BeiDou GEO satellites and reflected signal from soil. Based on signal synchronization, the reflectivity of soil can be calculated according to the extracted signal power values. And then, the soil moisture can be obtained in light of the inversion model. By taking singals from BeiDou GEO satellites, not only the positioning calculation step of general GNSS-R data processing can be ignored, but also a continuous long-term observation of soil moisture for fixed area can be realized. Experiment results based on the method above show a good continuity in both time and magnitude. They are also highly consistent with reference values and the root mean square error equals to 0.049. Compared with BeiDou IGSO and GPS MEO satellites, BeiDou GEO satellites can present a better performance in soil moisture retrieval.

  2. One click film (OCF) dosimetry system for routine QA

    Energy Technology Data Exchange (ETDEWEB)

    Kim, So Young; Yi, Byong Yong; Kim, Jong Hoon; Ahn, Seung Do; Lee, Sang Wook; Choi, Eun Kyoung [Asan Medical Center, College of Medicine, University of Ulsan, Seoul (Korea, Republic of); Joo, Kwan Sik [MyongJi University, Yongin (Korea, Republic of)

    2002-12-15

    To develop a practical film dosimetry system for routine Quality Assurance (QA). An One Click Film (OCF) Dosimetry system was designed to perform swift routine QA with functions including automatic fog value elimination, angle adjustment, automatic symmetry calculation, and realtime profile generation with the ability to display realtime three-dimensional dose distributions. The most frequently used functions for routine QA, such as the elimination of the fog value, conversion into an H and D curve, symmetry, and isodose distribution, can be achieved with only one click. Reliable results were achieved with the OCF dosimetry with simpler steps than other commercially available film dosimetry systems for routine QA. More research on the refined user interface will make this system be clinically useful.

  3. Software for evaluation of EPR-dosimetry performance.

    Science.gov (United States)

    Shishkina, E A; Timofeev, Yu S; Ivanov, D V

    2014-06-01

    Electron paramagnetic resonance (EPR) with tooth enamel is a method extensively used for retrospective external dosimetry. Different research groups apply different equipment, sample preparation procedures and spectrum processing algorithms for EPR dosimetry. A uniform algorithm for description and comparison of performances was designed and implemented in a new computer code. The aim of the paper is to introduce the new software 'EPR-dosimetry performance'. The computer code is a user-friendly tool for providing a full description of method-specific capabilities of EPR tooth dosimetry, from metrological characteristics to practical limitations in applications. The software designed for scientists and engineers has several applications, including support of method calibration by evaluation of calibration parameters, evaluation of critical value and detection limit for registration of radiation-induced signal amplitude, estimation of critical value and detection limit for dose evaluation, estimation of minimal detectable value for anthropogenic dose assessment and description of method uncertainty.

  4. Retrospective dosimetry analyses of reactor vessel cladding samples

    Energy Technology Data Exchange (ETDEWEB)

    Greenwood, L. R.; Soderquist, C. Z. [Battelle Pacific Northwest National Laboratory, Richland, WA 99352 (United States); Fero, A. H. [Westinghouse Electric Company, Cranberry Twp., PA 16066 (United States)

    2011-07-01

    Reactor pressure vessel cladding samples for Ringhals Units 3 and 4 in Sweden were analyzed using retrospective reactor dosimetry techniques. The objective was to provide the best estimates of the neutron fluence for comparison with neutron transport calculations. A total of 51 stainless steel samples consisting of chips weighing approximately 100 to 200 mg were removed from selected locations around the pressure vessel and were sent to Pacific Northwest National Laboratory for analysis. The samples were fully characterized and analyzed for radioactive isotopes, with special interest in the presence of Nb-93m. The RPV cladding retrospective dosimetry results will be combined with a re-evaluation of the surveillance capsule dosimetry and with ex-vessel neutron dosimetry results to form a comprehensive 3D comparison of measurements to calculations performed with 3D deterministic transport code. (authors)

  5. Proceedings of the third conference on radiation protection and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Swaja, R.E.; Sims, C.S.; Casson, W.H. [eds.

    1991-10-01

    The Third Conference on Radiation Protection and Dosimetry was held during October 21--24, 1991, at the Sheraton Plaza Hotel in Orlando, Florida. This meeting was designed with the objectives of promoting communication among applied, research, regulatory, and standards personnel involved in radiation protection, and providing them with sufficient information to evaluate their programs. To meet these objectives, a technical program consisting of more than 75 invited and contributed oral presentations encompassing all aspects of radiation protection was prepared. General topics considered in the technical session included external dosimetry, internal dosimetry, instruments, accident dosimetry, regulations and standards, research advances, and applied program experience. In addition, special sessions were held to afford attendees the opportunity to make short presentations of recent work or to discuss topics of general interest. Individual reports are processed separately on the database.

  6. Geschlechtsunterschiede in der genetischen Übertragung bei Suchterkrankungen - eine Übersicht, basierend auf Familien-, Zwillings- und Adoptionsstudien

    Directory of Open Access Journals (Sweden)

    Franke P

    2003-01-01

    Full Text Available In der hier vorliegenden Übersicht sollen Geschlechtsunterschiede in der genetischen Übertragung von Suchterkrankungen anhand der bislang vorliegenden Daten aus Zwillings-, Adoptions- und Familienstudien dargestellt werden. Trotz der geringeren Prävalenz von substanzgebundener Abhängigkeit und Mißbrauch bei Frauen im Vergleich zu Männern in der Allgemeinbevölkerung, erscheint in Anbetracht der bislang vorliegenden Adoptions- und Zwillingsstudien die These, wonach Abhängigkeitserkrankungen bei Frauen weniger durch genetische Faktoren bedingt seien als bei Männern, nicht länger haltbar und bedarf einer Modifikation: Das Ausmaß der genetischen Einflüsse scheint demnach bei Männern und Frauen substanzspezifisch zu variieren. So deuten insbesondere die Daten aus Zwillingsstudien darauf hin, daß genetischen Faktoren bei Cannabis- und Kokainabhängigkeit unter Frauen sogar eine stärkere Bedeutung als bei Männern zukommt. Neuere Zwillingsstudien zeigen, daß bei der Opiatabhängigkeit genetische Faktoren auch bei Frauen eine Rolle spielen. Insgesamt besteht weiterer Forschungsbedarf hinsichtlich einer geschlechtsspezifischen Übertragung von Suchterkrankungen, da die bisherigen Ergebnisse und Schlußfolgerungen auf der Basis von Familien-, Zwillings- und Adoptionsstudien teilweise widersprüchlich und somit insgesamt als vorläufig zu betrachten sind.

  7. Dosimetry in Thermal Neutron Irradiation Facility at BMRR

    OpenAIRE

    2016-01-01

    Radiation dosimetry for Neutron Capture Therapy (NCT) has been performed since 1959 at Thermal Neutron Irradiation Facility (TNIF) of the three-megawatt light-water cooled Brookhaven Medical Research Reactor (BMRR). In the early 1990s when more effective drug carriers were developed for NCT, in which the eye melanoma and brain tumors in rats were irradiated in situ, extensive clinical trials of small animals began using a focused thermal neutron beam. To improve the dosimetry at irradiation f...

  8. Why is a high accuracy needed in dosimetry. [Radiotherapy

    Energy Technology Data Exchange (ETDEWEB)

    Lanzl, L.H.

    1976-01-01

    Dose and exposure intercomparisons on a national or international basis have become an important component of quality assurance in the practice of good radiotherapy. A high degree of accuracy of ..gamma.. and x radiation dosimetry is essential in our international society, where medical information is so readily exchanged and used. The value of accurate dosimetry lies mainly in the avoidance of complications in normal tissue and an optimal degree of tumor control.

  9. EPID dosimetry for pretreatment quality assurance with two commercial systems.

    Science.gov (United States)

    Bailey, Daniel W; Kumaraswamy, Lalith; Bakhtiari, Mohammad; Malhotra, Harish K; Podgorsak, Matthew B

    2012-07-05

    This study compares the EPID dosimetry algorithms of two commercial systems for pretreatment QA, and analyzes dosimetric measurements made with each system alongside the results obtained with a standard diode array. 126 IMRT fields are examined with both EPID dosimetry systems (EPIDose by Sun Nuclear Corporation, Melbourne FL, and Portal Dosimetry by Varian Medical Systems, Palo Alto CA) and the diode array, MapCHECK (also by Sun Nuclear Corporation). Twenty-six VMAT arcs of varying modulation complexity are examined with the EPIDose and MapCHECK systems. Optimization and commissioning testing of the EPIDose physics model is detailed. Each EPID IMRT QA system is tested for sensitivity to critical TPS beam model errors. Absolute dose gamma evaluation (3%, 3 mm, 10% threshold, global normalization to the maximum measured dose) yields similar results (within 1%-2%) for all three dosimetry modalities, except in the case of off-axis breast tangents. For these off-axis fields, the Portal Dosimetry system does not adequately model EPID response, though a previously-published correction algorithm improves performance. Both MapCHECK and EPIDose are found to yield good results for VMAT QA, though limitations are discussed. Both the Portal Dosimetry and EPIDose algorithms, though distinctly different, yield similar results for the majority of clinical IMRT cases, in close agreement with a standard diode array. Portal dose image prediction may overlook errors in beam modeling beyond the calculation of the actual fluence, while MapCHECK and EPIDose include verification of the dose calculation algorithm, albeit in simplified phantom conditions (and with limited data density in the case of the MapCHECK detector). Unlike the commercial Portal Dosimetry package, the EPIDose algorithm (when sufficiently optimized) allows accurate analysis of EPID response for off-axis, asymmetric fields, and for orthogonal VMAT QA. Other forms of QA are necessary to supplement the limitations of the

  10. Basic principles in the radiation dosimetry of nuclear medicine.

    Science.gov (United States)

    Stabin, Michael; Xu, Xie George

    2014-05-01

    The basic principles of the use of radiation dosimetry in nuclear medicine are reviewed. The basic structure of the main mathematical equations are given and formal dosimetry systems are discussed. An extensive overview of the history and current status of anthropomorphic models (phantoms) is given. The sources and magnitudes of uncertainties in calculated internal dose estimates are reviewed. Copyright © 2014 Elsevier Inc. All rights reserved.

  11. A practical three-dimensional dosimetry system for radiation therapy

    OpenAIRE

    Guo, Pengyi; Adamovics, John; Oldham, Mark

    2006-01-01

    There is a pressing need for a practical three-dimensional (3D) dosimetry system, convenient for clinical use, and with the accuracy and resolution to enable comprehensive verification of the complex dose distributions typical of modern radiation therapy. Here we introduce a dosimetry system that can achieve this challenge, consisting of a radiochromic dosimeter (PRESAGE™) and a commercial optical computed tomography (CT) scanning system (OCTOPUS™). PRESAGE™ is a transparent material with com...

  12. Individual dosimetry of workers and patients: implementation and perspectives; La dosimetrie individuelle des travailleurs et de patients: mise en oeuvre et perspectives

    Energy Technology Data Exchange (ETDEWEB)

    Rannou, A.; Aubert, B.; Lahaye, Th.; Scaff, P.; Casanova, Ph.; Van Bladel, L.; Queinnec, F.; Valendru, N.; Jehanno, J.; Grude, E.; Berard, Ph.; Desbree, A.; Kafrouni, H.; Paquet, F.; Vanhavere, F.; Bridier, A.; Ginestet, Ch.; Magne, S.; Donadille, L.; Bordy, J.M.; Bottollier-Depois, J.F.; Barrere, J.L.; Ferragut, A.; Metivier, H.; Gaillard-Lecanu, E

    2008-07-01

    These days organised by the section of the technical protection of the S.F.R.P. review the different techniques of dosimetry used in France and Europe, and present the future orientations.The different interventions are as follow: Individual exposures of the workers: historic assessment and perspectives; medical exposure: where are the doses; legal obligations in individual dosimetry: which are the objective and the need on the subject; the dosimetry follow-up of workers by the S.I.S.E.R.I. system: assessment and perspectives; impact of the norm ISO 20553 on the follow-up of internal exposure; the implementation of the patient dose measurement in Belgium; techniques of passive dosimetry used in Europe; Supervision radiation protection at EDF: long term and short term approach; Comparison active and passive dosimetry at Melox; methodology for the choice of new neutron dosemeters; the working group M.E.D.O.R.: guide of internal dosimetry for the use of practitioners; O.E.D.I.P.E.: tool of modeling for the personalized internal dosimetry; the use of the Monte-Carlo method for the planning of the cancer treatment by radiotherapy becomes a reality; the works of the committee 2 of the ICRP; passive dosimetry versus operational dosimetry: situation in Europe; Implementation of the in vivo dosimetry in a radiotherapy department: experience of the Gustave Roussy institute; experience feedback on the in vivo measures in radiotherapy, based on the use of O.S.L. pellets; multi points O.S.L. instrumentation for the radiation dose monitoring in radiotherapy; dosimetry for extremities for medical applications: principle results of the European contract C.O.N.R.A.D.; references and perspectives in dosimetry; what perspectives for numerical dosimetry, an example: Sievert; system of dose management: how to answer to needs; the last technical evolutions in terms of electronic dosimetry in nuclear power plant; the fourth generation type reactors: what dosimetry. (N.C.)

  13. The radiation dosimetry of intrathecally administered radionuclides

    Energy Technology Data Exchange (ETDEWEB)

    Stabin, M.G. [Oak Ridge Inst. for Science and Education, TN (United States); Evans, J.F. [Ohio State Univ., Columbus, OH (United States)

    1999-01-01

    The radiation dose to the spine, spinal cord, marrow, and other organs of the body from intrathecal administration of several radiopharmaceuticals was studied. Anatomic models were developed for the spine, spinal cerebrospinal fluid (CSF), spinal cord, spinal skeleton, cranial skeleton, and cranial CSF. A kinetic model for the transport of CSF was used to determine residence times in the CSF; material leaving the CSF was thereafter assumed to enter the bloodstream and follow the kinetics of the radiopharmaceutical as if intravenously administered. The radiation transport codes MCNP and ALGAMP were used to model the electron and photon transport and energy deposition. The dosimetry of Tc-99m DTPA and HSA, In-111 DTPA, I-131 HSA, and Yb-169 DTPA was studied. Radiation dose profiles for the spinal cord and marrow in the spine were developed and average doses to all other organs were estimated, including dose distributions within the bone and marrow.

  14. Accidental neutron dosimetry with human hair

    Science.gov (United States)

    Ekendahl, Daniela; Bečková, Věra; Zdychová, Vlasta; Bulánek, Boris; Prouza, Zdeněk; Štefánik, Milan

    2014-11-01

    Human hair contains sulfur, which can be activated by fast neutrons. The 32S(n,p)32P reaction with a threshold of 2.5 MeV was used for fast neutron dose estimation. It is a very important parameter for individual dose reconstruction with regards to the heterogeneity of the neutron transfer to the human body. Samples of human hair were irradiated in a radial channel of a training reactor VR-1. 32P activity in hair was measured both, directly by means of a proportional counter, and as ash dispersed in a liquid scintillator. Based on neutron spectrum estimation, a relationship between the neutron dose and induced activity was derived. The experiment verified the practical feasibility of this dosimetry method in cases of criticality accidents or malevolent acts with nuclear materials.

  15. EPR tooth dosimetry of SNTS area inhabitants

    Energy Technology Data Exchange (ETDEWEB)

    Sholom, Sergey [Scientific Center for Radiation Medicine, Melnikova str., 53, Kiev (Ukraine); Desrosiers, Marc [Ionizing Radiation Division, National Institute of Standards and Technology, Gaithersburg, MD (United States); Bouville, Andre; Luckyanov, Nicholas [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 6120 Executive Boulevard, Bethesda, MD (United States); Chumak, Vadim [Scientific Center for Radiation Medicine, Melnikova str., 53, Kiev (Ukraine); Simon, Steven L. [Division of Cancer Epidemiology and Genetics, National Cancer Institute, National Institutes of Health, 6120 Executive Boulevard, Bethesda, MD (United States)], E-mail: ssimon@mail.nih.gov

    2007-07-15

    The determination of external dose to teeth of inhabitants of settlements near the Semipalatinsk Nuclear Test Site (SNTS) was conducted using the EPR dosimetry technique to assess radiation doses associated with exposure to radioactive fallout from the test site. In this study, tooth doses have been reconstructed for 103 persons with all studied teeth having been formed before the first nuclear test in 1949. Doses above those received from natural background radiation, termed 'accident doses', were found to lie in the range from zero to approximately 2 Gy, with one exception, a dose for one person from Semipalatinsk city was approximately 9 Gy. The variability of reconstructed doses within each of the settlements demonstrated heterogeneity of the deposited fallout as well as variations in lifestyle. The village mean external gamma doses for residents of nine settlements were in the range from a few tens of mGy to approximately 100 mGy.

  16. Dosimetry for radiocolloid therapy of cystic craniopharyngiomas

    CERN Document Server

    Rojas, E L; Lallena, A M; Bodineau, C; Galan, P; Al-Dweri, Feras M.O.; Lallena, Antonio M.; Bodineau, Coral; Galan, Pedro

    2003-01-01

    The dosimetry for radiocolloid therapy of cystic craniopharyngiomas is investigated. Analytical calculations based on the Loevinger and the Berger formulae for electrons and photons, respectively, are compared with Monte Carlo simulations. The role of the material of which the colloid introduced inside the craniopharyngioma is made of as well as that forming the cyst wall is analyzed. It is found that the analytical approaches provide a very good description of the simulated data in the conditions where they can be applied (i.e., in the case of a uniform and infinite homogeneous medium). However, the consideration of the different materials and interfaces produces a strong reduction of the dose delivered to the cyst wall in relation to that predicted by the Loevinger and the Berger formulae.

  17. EPR-dosimetry with carious teeth

    Energy Technology Data Exchange (ETDEWEB)

    Sholom, S.V. E-mail: sholom@leed1.kiev.ua; Haskell, E.H.; Hayes, R.B.; Chumak, V.V.; Kenner, G.H

    2000-12-15

    The effect of caries in EPR dosimetry of tooth enamel (in the dose range of 0-1 Gy) was investigated. The enamel of each tooth was divided into carious, non-carious and intermediate portions. The EPR signals of enamel at g=2.0018 (dosimetric) and g=2.0045 (native) were examined. The intensity of the dosimetric signal was the same for all three portions, while that of the native signal was higher for carious portions than for non-carious and intermediate portions. Reconstruction of the laboratory applied doses was done using all portions. Reasonable correlation between nominal and reconstructed doses was found in most cases. The effect of alkali treatment on the native and dosimetric signals of enamel was also tested. Reduction of the native signal intensity, particularly in the carious portions, was found to be the only significant effect. This resulted in a slight improvement in the accuracy of the reconstructed doses.

  18. In vivo dosimetry during tangential breast treatment

    Energy Technology Data Exchange (ETDEWEB)

    Heukelom, S.; Lanson, J.H.; Tienhoven, G. van; Mijnheer, B.J. (Nederlands Kanker Inst. ' Antoni van Leeuwenhoekhuis' , Amsterdam (Netherlands))

    1991-12-01

    Three-dimensional (3-D) dose distribution as calculated in clinical practice for tangential breast treatment was verified through in vivo dosimetry. Clinical practice at Netherlands Cancer Institute implies use of 8MV X-ray beams, 2-D treatment planning system, collimator rotation and a limited set of patient data for dose calculations. By positioning diodes at the central beam axes as well as in the periphery of the breast the magnitude of dose values at the isocentre and in points situated in high-dose regions behind the lung could be assessed. The position of diodes was verified by means of an on-line portal imaging device. Reproducibility of these in vivo dose measurements was better than 2% (1SD). This study shows that on the average dose delivery at the isocentre is 2% less at the points behind the lung, 5.7% higher with respect to the calculated dose values. Detailed analysis of these in vivo dosimetry results, based on dose measurements performed with a breast shaped phantom, yielded the magnitudes of errors in predicted dose due to several limitations in dose calculation algorithms and dose calculation procedure. These limitations are each introducing an error of several percent but are compensating each other for the dose calculation at the isocentre. It is concluded that dose distribution in patient for this treatment technique and dose calculation procedure can be predicted with a 2-D treatment planning system in an acceptable way. A more accurate prediction of dose distribution can be performed but requires an estimation of the lack of scatter due to missing tissue, the change in the dose distribution due to oblique incident beams and incorporation of the actual output of the treatment machine in the assessment of the number of monitor units. (author). 28 refs.; 3 figs.; 4 tabs.

  19. Fast neutron activation dosimetry with TLDS

    Energy Technology Data Exchange (ETDEWEB)

    Pearson, D.W.; Moran, P.R.

    1975-01-01

    Fast neutron activation using threshold reactions is the only neutron dosimetry method which offers complete discrimination against gamma-rays and preserves some information about the neutron energy. Conventional activation foil technique requires sensitive radiation detectors to count the decay of the neutron induced activity. For extensive measurements at low neutron fluences, vast outlays of counting equipment are required. TL dosimeters are inexpensive, extremely sensitive radiation detectors. The work of Mayhugh et al. (Proc. Third Int. Conf. on Luminescence Dosimetry, Riso Report 249, 1040, (1971)) showed that CaSO/sub 4/: DyTLDs could be used to measure the integrated dose from the decay of the radioactivity produced in the dosimeters by exposure to thermal neutrons. This neatly combines the activation detector and counter functions in one solid state device. This work has been expanded to fast neutron exposures and other TL phosphors. The reactions /sup 19/F(n, 2n)/sup 18/F, /sup 32/S(n,p)/sup 32/P, /sup 24/Mg(n,p)/sup 24/, and /sup 64/Zn(n,p)/sup 64/Cu were found useful for fast neutron activation in commercial TLDs. As each TLD is its own integrating decay particle counter, many activation measurements can be made at the same time. The subsequent readings of the TL signals can be done serially after the induced radioactivity has decayed, using only one TL reader. The neutron detection sensitivity is limited mainly by the number statistics of the neutron activations. The precision of the neutron measurement is within a factor of two of conventional foil activation for comparable mass detectors. Commercially available TLDs can measure neutron fluences of 10/sup 9/n/cm/sup 2/ with 10 percent precision.

  20. High sensitive radiation detector for radiology dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Valente, M.; Malano, F. [Instituto de Fisica Enrique Gaviola, Oficina 102 FaMAF - UNC, Av. Luis Medina Allende, Ciudad Universitaria, 5000 Cordoba (Argentina); Molina, W.; Vedelago, J., E-mail: valente@famac.unc.edu.ar [Laboratorio de Investigaciones e Instrumentacion en Fisica Aplicada a la Medicina e Imagenes por Rayos X, Laboratorio 448 FaMAF - UNC, Ciudad Universitaria, 5000 Cordoba (Argentina)

    2014-08-15

    Fricke solution has a wide range of applications as radiation detector and dosimetry. It is particularly appreciated in terms of relevant comparative advantages, like tissue equivalence when prepared in aqueous media like gel matrix, continuous mapping capability, dose rate recorded and incident direction independence as well as linear dose response. This work presents the development and characterization of a novel Fricke gel system, based on modified chemical compositions making possible its application in clinical radiology. Properties of standard Fricke gel dosimeter for high dose levels are used as starting point and suitable chemical modifications are introduced and carefully investigated in order to attain high resolution for low dose ranges, like those corresponding to radiology interventions. The developed Fricke gel radiation dosimeter system achieves the expected typical dose dependency, actually showing linear response in the dose range from 20 up to 4000 mGy. Systematic investigations including several chemical compositions are carried out in order to obtain a good enough dosimeter response for low dose levels. A suitable composition among those studied is selected as a good candidate for low dose level radiation dosimetry consisting on a modified Fricke solution fixed to a gel matrix containing benzoic acid along with sulfuric acid, ferrous sulfate, xylenol orange and ultra-pure reactive grade water. Dosimeter samples are prepared in standard vials for its in phantom irradiation and further characterization by spectrophotometry measuring visible light transmission and absorbance before and after irradiation. Samples are irradiated by typical kV X-ray tubes and calibrated Farmer type ionization chamber is used as reference to measure dose rates inside phantoms in at vials locations. Once sensitive material composition is already optimized, dose-response curves show significant improvement regarding overall sensitivity for low dose levels. According to

  1. Personal Dosimetry Enhancement for Underground Workplaces

    Directory of Open Access Journals (Sweden)

    L. Thinová

    2005-01-01

    Full Text Available Personal dosimetry for underground workers mainly concerns measurement of the concentration of radon (and its daughters and the correct application of the data in dose calculation, using a biokinetic model for lung dosimetry. A conservative approach for estimating the potential dose in caves (or underground is based on solid state alpha track detector measurements. The obtained dataset is converted into an annual effective dose in agreement with the ICRP recommendations using the “cave factor”, the value of which depends on the spectrum of aerosol particles, or on the proportional representation of the unattached and the attached fraction and on the equilibrium factor. The main difference between apartments and caves is the absence of aerosol sources, high humidity, low ventilation rate and the uneven surface in caves. A more precisely determined dose value would have a significant impact on radon remedies or on restricting the time workers stay underground. In order to determine  how the effective dose is calculated, it is necessary to divide these areas into distinct categories by the following measuring procedures: continual radon measurement (to capture the differences in EERC between working hours and night-time, and also between daily and seasonal radon concentration variations; regular measurements of radon and its daughters to estimate the equilibrium factor and the presence of 218Po; regular indoor air flow measurements to study the location of the radon supply and its transfer among individual areas of the cave; natural radioactive element content evaluation in subsoils and in water inside/outside, a study of the radon sources in the cave; aerosol particle-size spectrum measurements to determine the free fraction; monitoring the behaviour of guides and workers to record the actual time spent in the cave, in relation to the continuously monitored levels of Rn concentration. 

  2. Latest developments in silica fibre luminescence dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Bradley, D. A.; Abdul S, S. F.; Jafari, S. M.; Alanazi, A. [University of Surrey, Department of Physics, GU2 7XH Guildford, Surrey (United Kingdom); Amouzad M, G. [University of Malaya, Faculty of Engineering, Department of Electrical Engineering, Integrated Lightwave Research Group, 50603 Kuala Lumpur (Malaysia); Addul R, H. A.; Mizanur R, A. K. M.; Zubair, H. T.; Begum, M.; Yusoff, Z.; Omar, N. Y. M. [Multimedia University, Faculty of Engineering, 2010 Cyberjaya, Selangor (Malaysia); Maah, M. J. [University of Malaya, Department of Chemistry, 50603 Kuala Lumpur (Malaysia); Collin, S. [National Physical Laboratory, Hampton Road, Teddington, TW11 OLW Middlesex (United Kingdom); Mat-Sharif, K. A.; Muhd-Yassin, S. Z.; Zulkifli, M. I., E-mail: d.a.bradley@surrey.ac.uk [Telekom Malaysia Research and Development Sdn Bhd., 63000 Cyberjaya, Selangor (Malaysia)

    2015-10-15

    Full text: Using tailor made sub-mm diameter doped-silica fibres, we are carrying out luminescence dosimetry studies for a range of situations, including thermoluminescence (Tl)investigations on a liquid alpha source formed of {sup 223}RaCl (the basis of the Bayer Health care product Xofigo), the Tl response to a 62 MeV proton source and Tl response to irradiation from an {sup 241}Am-Be neutron source. In regard to the former, in accord with the intrinsic high linear energy transfer (Let) and short path length (<100 um) of the α-particles in calcified tissue, the product is in part intended as a bone-seeking radionuclide for treatment of metastatic cancer, offering high specificity and efficacy. The Tl yield of Ge-doped SiO{sub 2} fibres has been investigated including for photonic crystal fibre un collapsed, flat fibres and single mode fibres, these systems offering many advantages over conventional passive dosimetry types. In particular, one can mention comparable and even superior sensitivity, an effective atomic number Z{sub eff} of the silica dosimetric material close to that of bone, and the glassy nature of the fibres offering the additional advantage of being able to place such dosimeters directly into liquid environments. Finally we review the use of our tailor made fibres for on-line radioluminescence measurements of radiotherapy beams. The outcome from these various lines of research is expected to inform development of doped fiber radiation dosimeters of versatile utility, ranging from clinical applications through to industrial studies and environmental evaluations. (Author)

  3. Dosimetry of low-energy beta radiation

    Energy Technology Data Exchange (ETDEWEB)

    Borg, J.

    1996-08-01

    Useful techniques and procedures for determination of absorbed doses from exposure in a low-energy {beta} radiation field were studied and evaluated in this project. The four different techniques included were {beta} spectrometry, extrapolation chamber dosimetry, Monte Carlo (MC) calculations, and exoelectron dosimetry. As a typical low-energy {beta} radiation field a moderated spectrum from a {sup 14}C source (E{sub {beta}},{sub max} =156 keV) was chosen for the study. The measured response of a Si(Li) detector to photons (bremsstrahlung) showed fine agreement with the MC calculated photon response, whereas the difference between measured and MC calculated responses to electrons indicates an additional dead layer thickness of about 12 {mu}m in the Si(Li) detector. The depth-dose profiles measured with extrapolation chambers at two laboratories agreed very well, and it was confirmed that the fitting procedure previously reported for {sup 147}Pm depth-dose profiles is also suitable for {beta} radiation from {sup 14}C. An increasing difference between measured and MC calculated dose rates for increasing absorber thickness was found, which is explained by limitations of the EGS4 code for transport of very low-energy electrons (below 10-20 keV). Finally a study of the thermally stimulated exoelectron emission (TSEE) response of BeO thin film dosemeters to {beta} radiation for radiation fields with maximum {beta} energies ranging from 67 keV to 2.27 MeV is reported. For maximum {beta} energies below approximately 500 keV, a decrease in the response amounting to about 20% was observed. It is thus concluded that a {beta} dose higher than about 10 {mu}Gy can be measured with these dosemeters to within 0 to -20% independently of the {beta}energy for E{sub {beta}},{sub max} values down to 67 keV. (au) 12 tabs., 38 ills., 71 refs.

  4. Radiotherapy for treatment of induratio penis plastica; Strahlentherapie bei Induratio penis plastica

    Energy Technology Data Exchange (ETDEWEB)

    Bruns, F.; Kardels, B.; Schaefer, U.; Schoenekaes, K.; Willich, N. [Westfaelische Wilhelms-Univ., Muenster (Germany). Klinik und Poliklinik fuer Strahlentherapie-Radioonkologie

    1999-06-01

    Radiotherapy is shown to be an effective, low-cost and non-invasive modality for treatment of induratio penis plastica. Its efficiency could be proven especially for inflammatory stages of the disease, or as an alternative after failure of conventional treatment. A total dose of no more than 20-25 Gy was found to achieve clear improvements in two thirds of the patients treated, while avoiding at the same time cosmetically disadvantageous late effects. (orig./CB) [Deutsch] Die Strahlentherapie ist eine wirksame, kostenguenstige und nicht-invasive Behandlungsmoeglichkeit bei Induratio penis plastica. Ihren Stellenwert konnte sie insbesondere im inflammatorischen Stadium und nach Versagen anderer konservativer Therapieansaetze zeigen. Eine Gesamteinstrahldosis von 20-25 Gy reicht aus, um bei 2/3 der Patienten eine deutliche Besserung der Symptomatik zu erzielen bei gleichzeitiger Vermeidung kosmetisch relevanter Spaetnebenwirkungen. (orig.)

  5. Review of the near-earth space radiation dosimetry

    Science.gov (United States)

    Guo, Jianming; Chen, Xiaoqian; Li, Shiyou

    2016-07-01

    The near-earth space radiation environment has a great effect to the spacecraft and maybe do harm to the astronaut's health. Thus, how to measure the radiation has become a serious challenge. In order to provide sufficient protection both for astronauts and for instruments on-board, dose equivalent and linear energy transfer should be measured instead of merely measuring total radiation dose. This paper reviews the methods of radiation measurement and presents a brief introduction of dosimetry instruments. The method can be divided into two different kinds, i.e., positive dosimetry and passive dosimetry. The former usually includes electronic devices which can be used for data storage and can offer simultaneous monitoring on space radiation. The passive dosimetry has a much simple structure, and need extra operation after on-orbit missions for measuring. To get more reliable data of radiation dosimetry, various instruments and methods had been applied in the spacecrafts and the manned spacecrafts in particular. The outlook of the development in the space radiation dosimetry measurement is also presented.

  6. Magnetic resonance imaging of dilated cardiomyopathy; MRT bei dilatativen Kardiomyopathien

    Energy Technology Data Exchange (ETDEWEB)

    D' Anastasi, M. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Greif, M. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Medizinische Klinik und Poliklinik I, Muenchen (Germany); Reiser, M.F.; Theisen, D. [Klinikum der Ludwig-Maximilians-Universitaet Muenchen, Campus Grosshadern, Institut fuer Klinische Radiologie, Muenchen (Germany); Deutsches Zentrum fuer Herzkreislaufforschung (DZHK), Muenchen (Germany)

    2013-01-15

    Dilated cardiomyopathy (DCM) is the most common type of cardiomyopathy with a prevalence of 1 out of 2,500 in adults. Due to mild clinical symptoms in the early phase of the disease, the true prevalence is probably even much higher. Patients present with variable clinical symptoms ranging from mild systolic impairment of left ventricular function to congestive heart failure. Even sudden cardiac death may be the first clinical symptom of DCM. The severity of the disease is defined by the degree of impairment of global left ventricular function. Arrhythmias, such as ventricular or supraventricular tachycardia, atrioventricular (AV) block, ventricular extrasystole and atrial fibrillation are common cardiac manifestations of DCM. Magnetic resonance imaging (MRI) plays an important role in the exact quantification of functional impairment of both ventricles and in the evaluation of regional wall motion abnormalities. With its excellent ability for the assessment of myocardial structure, it is becoming increasingly more important for risk stratification and therapy guidance. (orig.) [German] Die dilatative Kardiomyopathie (DCM) ist die haeufigste Form der Kardiomyopathie mit einer Praevalenz von 1/2500 Erwachsenen. Aufgrund der zunaechst milden klinischen Symptomatik ist jedoch von einer relativ hohen Dunkelziffer auszugehen. Die klinische Praesentation ist variabel, die Schwere der Erkrankung wird vom Ausmass der systolischen Funktionseinschraenkung bestimmt. Herzrhythmusstoerungen, wie ventrikulaere oder supraventrikulaere Tachykardien, AV-Blockierungen, ventrikulaere Extrasystolen und Vorhofflimmern sind moegliche klinische Manifestationen. Bei manchen Patienten ist der ploetzliche Herztod die erste klinische Manifestation der Erkrankung. Die kardiale MRT spielt eine bedeutende Rolle fuer die Beurteilung des Ausmasses der ventrikulaeren Dilatation, Dysfunktion und fuer die Beurteilung regionaler Wandbewegungsstoerungen. Darueber hinaus kann sie zur Anwendung kommen

  7. Diätetische Maßnahmen bei Prostatakarzinom

    Directory of Open Access Journals (Sweden)

    Hübner W

    2001-01-01

    Full Text Available Der Einfluß diätetischer Gewohnheiten und Maßnahmen auf Krebserkrankungen und im speziellen auf das Entstehen eines Prostatakarzinoms haben im vergangenen Jahr auch in Europa große Publizität gewonnen. Es ist unsere Aufgabe als Urologen, auch auf diesem Gebiet kompetente Hilfestellung für unsere Patienten zu bieten. In der Folge möchte ich kurz auf Möglichkeiten, Grenzen und Indikationen diätetischer Maßnahmen beim Prostatakarzinom eingehen. Der Zusammenhang zwischen diätetischen Maßnahmen und klinischem Entstehen eines Prostatakarzinoms ist uns aus den sogenannten Emigrantenstudien bekannt. So konnte festgestellt werden, daß das Verhältnis der Prostatakrebsentstehung zwischen Japanern und weißen Amerikanern 1:5 beträgt, sich aber bei Japanern, die in 2. Generation in Amerika leben, gegenüber den weißen Amerikanern auf 1:1 verändert. Von den verschiedenen Umweltfaktoren und Lebensgewohnheiten werden in erster Linie Änderungen der Eßgewohnheiten nach der Emigration dafür verantwortlich gemacht. Der Einfluß verschiedener Eßgewohnheiten auf die Karzinomentstehung wurde in der Vergangenheit nicht nur von Naturheilern und Komplementärmedizinern angesprochen, in mehr als 1500 Artikeln zum Thema "Krebs und Diät" wurde diese Thematik in den vergangenen 2 Jahren auch in den Standard- und Topjournals der medizinischen Fachliteratur behandelt. Informationen zu den wichtigsten Diätinhaltsstoffen möchte ich hier zusammenfassen.

  8. Erhöhter oxidativer Streß bei Patienten mit instabiler Angina pectoris

    Directory of Open Access Journals (Sweden)

    Bodlaj G

    1998-01-01

    Full Text Available Die instabile Angina pectoris führt oft zum akuten Myokardinfarkt. Da die Lipid-Peroxidation im Verdacht steht, chronische und akute Ereignisse der Atherosklerose und der koronaren Herzkrankheit zu fördern, untersuchten wir die Lipid-Peroxidations-Parameter und alpha-Toco-pherol-Spiegel bei 100 KHK-Patienten und verglichen sie mit denen einer entprechenden Kontrollgruppe. 50 konsekutive Patienten mit stabiler Angina pectoris (SAP und 50 konsekutive Patienten mit instabiler Angina pectoris (IAP wurden untersucht und mit 100 klinisch gesunden Personen verglichen. Zusätzlich zur herkömmlichen Lipid- und Lipoprotein-Analyse wurden die Lipid-Peroxidations-Produkte als Hydroperoxide und Thiobarbituric acid reactive substances (TBARS gemessen. Die konjugierten Diene wurden nur bei den Patienten bestimmt. Da alpha-Tocopherol eines der wichtigsten Antioxidantien ist, wurde es ebenfalls quantifiziert. Wie erwartet hatten die Patienten wesentlich höhere Cholesterin-, Triglyzerid-, LDL-C- und Lp(a-Spiegel und niedrigere HDL-C-Spiegel als die Kontrollgruppe. Als die Patienten in Gruppen mit stabiler und instabiler Angina pectoris geteilt wurden, waren Peroxide und TBARS in der letzteren Gruppe wesentlich höher als bei den anderen Patienten und der Kontrollgruppe. Auch konjugierte Diene waren eindeutig höher bei den Patienten mit instabiler Angina pectoris. Der alpha-Tocopherol-Gesamtspiegel war in allen 3 Gruppen vergleichbar, aber der alpha-Tocopherol-Gehalt pro LDL-Partikel war bei den Patienten mit IAP am niedrigsten, gefolgt von denen mit SAP und der Kontrollgruppe. Wir schließen daraus, daß die Lipid-Peroxidations-Parameter bei Patienten mit IAP erhöht sind und SAP-Patienten von IAP-Patienten unterscheiden.

  9. Harnableitung bei Kindern und Jugendlichen mit neurogener Blasenfunktionsstörung: auch langfristig eine sichere Therapieoption?

    Directory of Open Access Journals (Sweden)

    Stein R

    2002-01-01

    Full Text Available Einleitung: Pharmakotherapie, der saubere Einmalkatheterismus (clean intermittent catheterization = CIC und die Infektionsprophylaxe sind die drei Säulen der konservativen Therapie bei Patienten mit neurogener Blasenfunktionsstörung. Während der Pubertät werden die Patienten zunehmend unabhängiger vom Elternhaus. Gleichzeitig nimmt jedoch die Compliance der Medikamenteneinnahme und der Durchführung des regelmäßigen CIC ab. Der orthopädische und/oder neurologische Status kann sich ebenfalls verändern. Dies kann letztlich zum Fehlschlagen der konservativen Therapie (Inkontinenz, Restharn, Verschlechterung der Funktion des oberen Harntraktes führen. In einem multidisziplinären Team wird diese Problematik der Kinder und Jugendlichen unter Berücksichtigung der Wünsche des Patienten als auch der medizinischen Ziele (z. B. Schutz der Nierenfunktion in unserer Klinik diskutiert. Die Harnableitung wurde hierbei in einigen Fällen als notwendige Kompromißlösung angesehen. In der vorliegenden retrospektiven Studie untersuchten wir, ob die Harnableitung auch langfristig ein sicheres Verfahren darstellt. Material und Methode: Zwischen 1967 und 1997 erfolgte bei 149 Kindern und Heranwachsenden die Anlage einer Harnableitung. 129 Patienten konnten durchschnittlich 11,8 Jahre (0,8-28,5 nachbeobachtet werden. Das durchschnittliche Alter bei der Operation betrug 12,1 Jahre (0,8-20. Ein Colon-Conduit wurde bei 59 Patienten (in der Mehrzahl der Fälle vor der Ära des CIC und der kontinenten Harnableitung angelegt, eine orthotope Blasensubstitution erfolgte bei 12, eine kontinente kutane Harnableitung bei 58 Patienten (50 % Rollstuhlfahrer. Ergebnisse: Der obere Harntrakt blieb bei 95-97 % der renoureteralen Einheiten (RUE stabil, bzw. verbesserte sich. Alle Patienten mit einer orthotopen Blasensubstitution sind tagsüber kontinent; eine Patientin benötigt zur Sicherheit zeitweise eine Vorlage während der Nacht. 7 der 12 Patienten führen einen

  10. Percutaneous abscess drainage in Crohn`s disease; Perkutane Abszessdrainage bei Morbus Crohn

    Energy Technology Data Exchange (ETDEWEB)

    Strotzer, M.; Manke, C.; Feuerbach, S. [Klinikum der Univ. Regensburg (Germany). Inst. fuer Roentgendiagnostik; Lock, G.; Bregenzer, N.; Schoelmerich, J. [Klinikum der Univ. Regensburg (Germany). Klinik und Poliklinik fuer Innere Medizin I

    1998-11-01

    Purpose: To evaluate the success of percutaneous, CT-guided abscess drainage (PAD) in patients with Crohn`s disease. Methods: Within the last 5 years 8 patients with Crohn`s disease were treated by PAD for intra-abdominal abscesses. A fistula was determined to be the cause in 4 patients. The abscesses arose spontaneously in 7 patients while one patient had a postperative abscess. We used single lumen 10F- and double lumen 12F- and 14F-catheters for drainage (duration of drainage 8-20 days). Results: In all cases the abscess was successfully drained by PAD. However, an operation-free interval of at least three months was achieved in only two patients. A healing of the fistula was not attained in any of the 4 patients with a proven fistula. No enterocutaneous fistulas arose within the course of PAD. Conclusions: PAD is also useful for patients with Crohn`s disease since it improves the starting situation for the necessary operative interventions. In most cases (especially with enterogenic fistulas), however, a long-lasting therapeutic result cannot be expected. (orig.) [Deutsch] Ziel: Bewertung des Erfolges der perkutanen CT-gezielten Abszessdrainage (PAD) bei Patienten mit Morbus Crohn. Methoden: 8 Patienten mit Morbus Crohn wurden innerhalb der letzten 5 Jahre wegen intraabdomineller Abszesse mittels PAD behandelt. Als Ursache wurde bei 4 Patienten eine Fistel nachgewiesen. Bei 7 Patienten waren die Abszesse spontan entstanden, bei einem Patienten handelte es sich um einen postoperativen Abszess. Zum Einsatz kamen einlumige 10F- und doppellumige 12F- und 14F-Drainagekatheter (Drainagedauer 8-20 Tage). Ergebnisse: In allen Faellen konnte durch die PAD eine Entlastung der Abszesse erzielt werden. Ein operationsfreies Intervall von mindestens drei Monaten wurde nur bei zwei Patienten erreicht. Bei keinem der 4 Patienten mit Fistelnachweis wurde eine Ausheilung der Fistel erreicht. Es kam im Rahmen der PAD zu keiner Bildung von enterokutanen Fisteln. Schlussfolgerungen

  11. Radiation protection dosimetry in medicine - Report of the working group n.9 of the European radiation dosimetry group (EURADOS) - coordinated network for radiation dosimetry (CONRAD - contract EC N) fp6-12684; Dosimetrie pour la radioprotection en milieu medical - rapport du groupe de travail n. 9 du European radiation dosimetry group (EURADOS) - coordinated netword for radiation dosimetry (CONRAD - contrat CE fp6-12684)

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2009-07-01

    This report present the results achieved within the frame of the work the WP 7 (Radiation Protection Dosimetry of Medical Staff) of the coordination action CONRAD (Coordinated Network for Radiation Dosimetry) funded through the 6. EU Framework Program. This action was coordinated by EURADOS (European Radiation Dosimetry Group). EURADOS is an organization founded in 1981 to advance the scientific understanding and the technical development of the dosimetry of ionising radiation in the fields of radiation protection, radiobiology, radiation therapy and medical diagnosis by promoting collaboration between European laboratories. WP7 coordinates and promotes European research for the assessment of occupational exposures to staff in therapeutic and diagnostic radiology workplaces. Research is coordinated through sub-groups covering three specific areas: 1. Extremity dosimetry in nuclear medicine and interventional radiology: this sub-group coordinates investigations in the specific fields of the hospitals and studies of doses to different parts of the hands, arms, legs and feet; 2. Practice of double dosimetry: this sub-group reviews and evaluates the different methods and algorithms for the use of dosemeters placed above and below lead aprons in large exposure during interventional radiology procedures, especially to determine effective doses to cardiologists during cardiac catheterization; and 3. Use of electronic personal dosemeters in interventional radiology: this sub-group coordinates investigations in laboratories and hospitals, and intercomparisons with passive dosemeters with the aim to enable the formulation of standards. (authors)

  12. Working memory in volunteers and schizophrenics using BOLD fMRI; Das Arbeitsgedaechtnis bei Gesunden und bei Schizophrenen: Untersuchungen mit BOLD-fMRT

    Energy Technology Data Exchange (ETDEWEB)

    Giesel, F.L. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (Germany); Deutsches Krebsforschungszentrum (DKFZ), Abteilung Radiologie, Heidelberg (Germany); Hohmann, N. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (Germany); Psychiatrische Universitaetsklinik Heidelberg, Sektion Gerontopsychiatrie (Germany); Seidl, U.; Kress, K.R.; Schoenknecht, P.; Schroeder, J. [Psychiatrische Universitaetsklinik Heidelberg, Sektion Gerontopsychiatrie (Germany); Kauczor, H.-U.; Essig, M. [Deutsches Krebsforschungszentrum (DKFZ) Heidelberg, Abteilung Radiologie (Germany)

    2005-02-01

    Functional magnetic resonance imaging uses the blood oxygen level-dependent effect (BOLD MRI) for noninvasive display of cerebral correlatives of cognitive function. The importance for the understanding of physiological and pathological processes is demonstrated by investigations of working memory in schizophrenics and healthy controls. Working memory is involved in processing rather than storage of information and therefore is linked to complex processes such as learning and problem solving. In schizophrenic psychosis, these functions are clearly restricted. Training effects in the working memory task follow an inverse U-shape function, suggesting that cerebral activation reaches a peak before economics of the brain find a more efficient method and activation decreases. (orig.) [German] Die funktionelle Magnetresonanztomographie (fMRT) nutzt den ''blood oxygen level dependent effect'' (BOLD-Effekt) zur nichtinvasiven Darstellung zerebraler Korrelate kognitiver Funktionen. Die Bedeutung dieses Verfahrens fuer das Verstaendnis physiologischer und pathologischer Prozesse wird anhand von Untersuchungen zum Arbeitsgedaechtnis bei Schizophrenen und gesunden Kontrollpersonen verdeutlicht. Das Arbeitsgedaechtnis dient weniger der Speicherung, sondern vielmehr der Verarbeitung von Informationen und ist deshalb in komplexe Prozesse wie Lernen und Problemloesen eingebunden. Im Rahmen schizophrener Psychosen kommt es zu einer deutlichen Einschraenkung dieser Funktionen. Erwartungsgemaess zeigen sich unter Durchfuehrung eines Arbeitsgedaechtnisparadigmas Unterschiede in der zerebralen Aktivitaet, die jedoch bei den Erkrankten unter Therapie prinzipiell reversibel sind. Von Interesse sind auch Trainingseffekte bei Gesunden, wobei eine verminderte Aktivierung nach Training auf eine ''Oekonomisierung'' schliessen laesst. (orig.)

  13. SIXTH ERDA WORKSHOP ON PERSONNEL NEUTRON DOSIMETRY

    Energy Technology Data Exchange (ETDEWEB)

    Vallario, E. J.; Hankins, D. E.; Bramson, P. E.

    1977-07-11

    This workshop was the sixth of a series and was held on July 11 and 12, 1977, at the Oak Ridge National Laboratory in Oak Ridge, Tennessee. Those presenting papers at the Sixth Workshop prepared summary reports of their recent work for inclusion in this document. The reports are reproduced here as submitted by the participants, with only minor editing. This year's Workshop took a decidedly international flavor, with participants from seven countries in addition to the United States. The significance of this group's contributions has raised the possibility that the next Neutron Dosimetry Workshop may be held in Europe. Of particular interest at the Workshop was the keynote address by Dr. Harald Rossi. He commented that there is evidence that 1) accepted values of RBE for low absorbed doses of neutrons may be low by an order of magnitude or more and 2) the risk of leukemia is significant at 0.5 rad to the bone narrow. A reduction of the limit for permissible neutron exposure, which could result from consideration of this information, would necessitate major improvements in our "middle ages" neutron dosimetry. A number of participants reported conversions to thermoluminescent dosimeter (TLD) systems. This move has not been unanimous, however, as there were several reports of apparently satisfactory fission fragment, activation foil, and NTA film dosimeters. While thementionof NTA film resulted in the usual discussion of energy cut off and humidity effects, it seems the use of NTA in accelerator environments still has some merit. Discussion of fission fragment dosimeters centered around track etching techniques, which have shown some improvement. Of particular interest was Tommasino's report on the use of polycarbonate centrifuge tubes as the sensitive element. Thermally stimulated exoelectron emission (TSEE), never very popular for personnel dosimetry, has lost additional ground with the report that the neutron/gamma response ratio is much less than

  14. A probabilistic gastrointestinal tract dosimetry model

    Science.gov (United States)

    Huh, Chulhaeng

    In internal dosimetry, the tissues of the gastrointestinal (GI) tract represent one of the most radiosensitive organs of the body with the hematopoietic bone marrow. Endoscopic ultrasound is a unique tool to acquire in-vivo data on GI tract wall thicknesses of sufficient resolution needed in radiation dosimetry studies. Through their different echo texture and intensity, five layers of differing echo patterns for superficial mucosa, deep mucosa, submucosa, muscularis propria and serosa exist within the walls of organs composing the alimentary tract. Thicknesses for stomach mucosa ranged from 620 +/- 150 mum to 1320 +/- 80 mum (total stomach wall thicknesses from 2.56 +/- 0.12 to 4.12 +/- 0.11 mm). Measurements made for the rectal images revealed rectal mucosal thicknesses from 150 +/- 90 mum to 670 +/- 110 mum (total rectal wall thicknesses from 2.01 +/- 0.06 to 3.35 +/- 0.46 mm). The mucosa thus accounted for 28 +/- 3% and 16 +/- 6% of the total thickness of the stomach and rectal wall, respectively. Radiation transport simulations were then performed using the Monte Carlo N-particle transport code (MCNP) 4C transport code to calculate S values (Gy/Bq-s) for penetrating and nonpenetrating radiations such as photons, beta particles, conversion electrons and auger electrons of selected nuclides, I123, I131, Tc 99m and Y90 under two source conditions: content and mucosa sources, respectively. The results of this study demonstrate generally good agreement with published data for the stomach mucosa wall. The rectal mucosa data are consistently higher than published data compared with the large intestine due to different radiosensitive cell thicknesses (350 mum vs. a range spanning from 149 mum to 729 mum) and different geometry when a rectal content source is considered. Generally, the ICRP models have been designed to predict the amount of radiation dose in the human body from a "typical" or "reference" individual in a given population. The study has been performed to

  15. Cooling rate effects in thermoluminescence dosimetry grade lithium flouride. Implications for practical dosimetry.

    Science.gov (United States)

    Mason, E W; McKinlay, A F; Clark, I

    1976-01-01

    A systematic investigation of the effects of cooling rates in the range of 10(-1) to 2 X 10(5) degrees C min-1 applied to TLD-700, LiF thermoluminescence dosemeters has shown that the 'transfer sensitivity' effect observed by Booth, Johnson and Attix (1972) is only of importance for cooling rates greater than 10(3) degrees C min-1. Although it is concluded that for practical dosimetry purposes the effect may be ignored it is not clear why Booth et al. observed such large changes and until this discrepancy is explained it is recommended that a low temperature pre-irradiation anneal should be used.

  16. Analgesic interventions for spinal diseases; Schmerztherapeutische Ansaetze bei Wirbelsaeulenerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Reith, W.; Yilmaz, U. [Universitaetsklinikum des Saarlandes, Klinik fuer Diagnostische und Interventionelle Neuroradiologie, Homburg/Saar (Germany)

    2011-09-15

    Zuordnung kann durch spezielle Nervenblockaden erfolgen. Voraussetzung zur Durchfuehrung einer diagnostischen Nervenblockade sind eine ausfuehrliche Schmerzanamnese und Untersuchung des Patienten vor der Blockade. Bei ca. 15-45% der Patienten sind die Facettengelenke Ursache der Rueckenschmerzen. Eine Anaesthesie der Facettengelenke kann durch direkte intraartikulaere Applikation des Lokalanaesthetikums oder durch Blockade des Ramus medialis des hinteren Asts von jeweils 2 Spinalnerven erfolgen. Am einfachsten ist eine computertomographisch gesteuerte Facettenblockade. (orig.)

  17. Ciencias contábeis, novos rumos , novas diretrizes curriculares

    Directory of Open Access Journals (Sweden)

    Patricia Dantas Trajano

    2009-09-01

    Full Text Available A nova Lei de Diretrizes e Bases da Educação Nacional, Lei n"9.394, de 20 de dezembro de 1996, em seu artigo 43, enfatiza que a educação superior tem por finalidade precípua a formação de profissionais aptos para inserção no mercado de trabalho e em condições de participarem ativamente do desenvolvimento da sociedade brasileira. Prevê, ainda, o incentivo a pesquisa, a educação continuada, assim como a promoção da divulgação de conhecimentos culturais, científicos e técnicos que constituam patrimônio da humanidade. O inciso II do artigo 53 da mesma Lei concede autonomia as Instituições de Ensino Superior (IES para "fixar os currículos dos seus cursos e programas, observadas as diretrizes gerais pertinentes", o que oferece as IES uma maior flexibilidade na elaboração de seu currículo pleno. A Resolução n2 03/92, do Conselho Federal de Educação, fixa, ate o momento, os mínimos de conteúdo e de duração do curso de graduação em Ciências Contábeis vigentes no pals. Estabelece que o currículo pleno das IES deva definir o perfil profissional a ser formado, em função das atribuições legais que lhe serão conferidas, das peculiaridades e necessidades da região em que as IES se encontram, de suas naturezas e características próprias. O currículo pleno deve ser dividido por disciplinas ou outras atividades curriculares obrigatórias eletivas, nas seguintes categorias de conhecimentos: Categoria I - Conhecimentos de Formação Geral de natureza humanística e social; Categoria II - Conhecimentos de Formação Profissional; Categoria III - Conhecimentos ou Atividades de Formação.

  18. Wer liest schon das "Kleingedruckte"? Urheberrecht bei Audioproduktion im Unterricht

    Directory of Open Access Journals (Sweden)

    Christian Berger

    2015-03-01

    Full Text Available Gesetze gelten, ob mensch diese kennt oder auch nicht kennt. Dieser Beitrag ist keine juristische Abhandlung sondern bietet praxisbezogene Wegweiser für LehrerInnen durch den juristischen Dschungel des Urheberrechtes und die Schaffung einer Basis für eine Verbreitung der schulischen Medienproduktionen ... Aus dem Alltag der SchülerInnen und LehrerInnen ist die Nutzung des Internets nicht mehr wegzudenken. Es ist also nicht überraschend, dass zahlreiche Audioproduktionen aus dem Unterricht im Internet zu finden sind. Weniger bekannt sind die rechtlichen Rahmenbedingungen, die hier zu beachten sind. Auf Webseiten findet man Nutzungsbedingungen für die Inhalte oftmals nur nach längerem Suchen – wenn überhaupt. Wenn aber da nicht zu lesen ist, in welcher Art die Inhalte der Webseite zu nutzen sind, dann ist außer dem Lesen, Ansehen, Anhören und Speichern auf dem eigenen Rechner nichts ohne Rückfrage bei den InhaberInnen der Seiten gestattet. Das Urheberrecht soll die Werke der kreativ Schaffenden vor unerlaubter Nutzung schützen und ihnen die Möglichkeit offen lassen, ihre Werke oder auch nur die Nutzung derselben zu verkaufen. Nun werden Sie sagen, dass es doch ganz normal sei in unserer kapitalistischen Gesellschaft, dass Werke zu Waren und am Marktplatz gehandelt werden. Aber ganz so klar und einfach ist das nicht, denn im Markt spielen noch mehr Beteiligte mit, die ebenfalls verdienen wollen. Nun werden Sie einwenden, dass die Schule eben kein Marktplatz sei und der Unterricht doch ganz andere Ziele verfolge. Richtig. Allerdings beinhaltet das derzeitige Urheberrecht hier keine Ausnahmeregelungen. Es gibt allerdings auch keine einfachen allgemeinen Regelungen, sondern viele Einzelfälle, die ihre Besonderheiten haben und unterschiedlich abzuhandeln sind. Konkret geht es um drei Bereiche der Gesetzgebung: das Urheberrecht, das Medienrecht und Schutzbestimmungen im "Persönlichkeitsrecht". Hier ist gleich einmal anzumerken, dass ein

  19. Verarbeitung negativer Rückmeldung mit unterschiedlich affektiver Wertigkeit bei Kindern : eine fMRT-Studie

    OpenAIRE

    Pelz, Sabrina

    2009-01-01

    Verarbeitung von negativem Feedback (Rückmeldung) mit unterschiedlich affektiver (emotionaler) Wertigkeit bei Kindern (10 bis 13 Jahre alt). FMRT-Studie und neuronale Korrelate. Paradigma: Pseudo-Chemie-Aufgabe. Feedback: zweiteilig; individuelles Feedback und verzögert Feedback einer Peergroup. Kontraste: negatives Feedback > positivem Feedback, hoch affektives negatives Feedback > niedrig affektives negatives Feedback und niedrig affektives negatives Feedback > hoch affektives nega...

  20. Behandlung von Herzrhythmusstörungen mit Magnesium bei Patienten mit Herzinsuffizienz

    Directory of Open Access Journals (Sweden)

    Wink K

    2002-01-01

    Full Text Available Die medikamentöse Behandlung von Herzrhythmusstörungen ist unbefriedigend, da bei guter Wirksamkeit durch die Proarrhythmie eine Verbesserung der Prognose gefährdet und nicht gesichert ist. Man kann davon ausgehen, daß Magnesiumsalze keine arrhythmogene Effekte aufweisen. Bei Patienten mit einer Herzinsuffizienz besteht häufig ein Mg-Mangel, der durch gastrointestinale Störungen, neurohormonale Regulationen, aber auch durch die Therapie (Diuretika,Digitalisbedingt ist. An Patienten mit einer Herzinsuffizienz müßte sich demnach zeigen lassen, ob die Mg-Substitution einen antiarrhythmischen Effekt aufweist. In fünf placebokontrollierten Studien konnte gezeigt werden, daß sich teil weise signifikant und mit ausreichen der Aussagekraft (PowerArrhythmien bei Patienten mit Herzinsuffizienz durch orale und parenterale Gabe von Mg-Salzen reduzieren lassen. Trotz Einschränkungen wie z.B. inadäquates Design, fehlende Vermeidung von Bias, ungenügende Vergleichbarkeit der Behandlungsgruppen, inadäquate Auswertung und ungenügende Berücksichtigung der Spontanvariation läßt sich aufgrund der Ergebnisse der Studien die Hypothese aufstellen, daß Magnesiumsalze bei Patienten mit Herzinsuffizienz Herzrhythmusstörungen günstig beeinflussen können. Prospektive, randomisierte,verblindete und kontrollierte konfirmatorische Studien mit ausreichenden Fallzahlen sind jedoch notwendig, um diese Hypothese zu bestätigen.

  1. Wirksamkeit und Verträglichkeit von Cyclophosphamid bei Multipler Sklerose: Eine retrospektive Analyse

    OpenAIRE

    2008-01-01

    Cyclophosphamid (Endoxan) ist ein zytostatisches Medikament, welches wegen seiner immunsuppressiven Wirkung eine breite Anwendung in der Therapie systemischer Autoimmunerkrankungen findet. Es wird als Medikation bei schwerer chronisch-progressiver Multipler Sklerose empfohlen, um die weitere Progredienz einzuschränken oder zu verhindern. Bisherige klinische Studien über den Wert dieses therapeutischen Einsatzes liefern aber kontroverse Ergebnisse. Aus diesem Grund erschien es sinnvoll...

  2. The 10th BeiDou 2 Navigation Satellite Flew into Space

    Institute of Scientific and Technical Information of China (English)

    2011-01-01

    LM launch vehicles established a new record by successfully performing the 16th successful flight this year.A LM-3A launched the 10th BeiDou 2 satellite into its predetermined transfer orbit on December 2 from the XSLC in Sichuan Province.

  3. Mitbestimmung von Studierenden bei der Qualitätssicherung und Hochschulentwicklung

    DEFF Research Database (Denmark)

    Lippert, Ingmar

    2005-01-01

    Hochschule hat bestimmte Aufgaben. Sie soll durch Forschung und Lehre Wissen und Methoden in die Gesellschaft tragen. Sie soll auch direkt andere gesellschaftliche Institutionen beraten. Bei diesen Interaktionen soll aber – und das ist so spezifisch für Hochschulen – die gesellschaftliche Praxis ...

  4. Der Satz des Nichtzuunterscheidenden : eine entwicklungsgeschichtliche Untersuchung eines philosophischen Prinzips bei Leibniz, Kant und Hegel

    OpenAIRE

    2005-01-01

    Die Aufgabe der vorliegenden Untersuchung bestand darin, den Leibnizschen Grundsatz des Nichtzuunterscheidenden in seiner philosophiegeschichtlichen Entwicklung darzustellen. Dies geschieht dadurch, dass die unterschiedlichen Auffassungen des Grundsatzes bei Leibniz, Kant und Hegel erläutert, sie miteinander verglichen und die Beziehungen dieser Auffassungen verdeutlicht werden. Die Gesichtspunkte, unter denen diese Aufgabe ausgeführt wurde, sind der Bedeutungswandel und der Wahrheits- bzw. G...

  5. BeiDou inter-satellite-type bias evaluation and calibration for mixed receiver attitude determination

    NARCIS (Netherlands)

    Nadarajah, N.; Teunissen, P.J.G.; Raziq, N.

    2013-01-01

    The Chinese BeiDou system (BDS), having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS). It consists of Geostationary Earth Orbit (GEO) satellites, Inclined Geosynchronous Satellite Orbit (IGSO) satellites and Medium

  6. BeiDou inter-satellite-type bias evaluation and calibration for mixed receiver attitude determination

    NARCIS (Netherlands)

    Nadarajah, N.; Teunissen, P.J.G.; Raziq, N.

    2013-01-01

    The Chinese BeiDou system (BDS), having different types of satellites, is an important addition to the ever growing system of Global Navigation Satellite Systems (GNSS). It consists of Geostationary Earth Orbit (GEO) satellites, Inclined Geosynchronous Satellite Orbit (IGSO) satellites and Medium Ea

  7. Über die Beziehung der Chorda zur Basalplatte bei Säugern

    NARCIS (Netherlands)

    Bolk, L.

    1922-01-01

    Es liegt in der Literatur schon eine stattliche Zahl von Veröffentlichungen vor, welche sich mit dem vorderen Abschnitt der Chorda dorsalis, oder kurzhin der Kopfchorda, bei Säugern, beschäftigen. Die auf diesen Gegenstand bezug habenden Publicationen lassen sich etwas gezwungen in zwei Gruppen

  8. Neurologisches Outcome nach CPR bei schockresistentem Kammerflimmern unter Gabe von Sedacoron(R

    Directory of Open Access Journals (Sweden)

    Müller R

    2003-01-01

    Full Text Available Bei einer protrahierten CPR mit schockresistentem Kammerflimmern kann unter Gabe von Sedacoron(R ein zufriedenstellender internistischer Zustand erreicht werden. Neurologisch bleiben nach 6 Wochen geringe Defizite des Kurzzeitgedächtnisses. Der Autor regt mit dieser Kasuistik eine Fortsetzung der ARREST- und der ALIVE-Studie an, wobei das neurologische Outcome Beachtung finden sollte.

  9. Der Zusammenhang zwischen medialem Multitasking, Aufmerksamkeitsfähigkeit und Hyperaktivität bei Jugendlichen

    NARCIS (Netherlands)

    Baumgartner, S.E.; Weeda, W.D.; Huizinga, M.; Kleinen von Königslöw, K.; Förster, K.

    2014-01-01

    Mediales Multitasking ist eine immer häufiger vorkommende Form der Mediennutzung, besonders bei Jugendlichen. Die wachsende Bedeutung dieser Form der Mediennutzung hat zu Bedenken über mögliche Auswirkungen geführt. So wird zum Beispiel angenommen, dass durch die ständige Stimulation mit verschieden

  10. Gezielte Rho-Kinase-Hemmung in Hepatischen Sternzellen als Therapie der portalen Hypertension bei der Leberzirrhose

    NARCIS (Netherlands)

    Klein, S.; Granzow, M.; Schierwagen, R.; Kilic, S.; Heidari, Iren; Huss, S.; van Beuge, Marike; Sauerbruch, T.; Poelstra, Klaas; Trebicka, J.

    2012-01-01

    Hintergund: Bei der Leberzirrhose ist die Rho-Kinase-Expression und Aktivität erhöht und verantwortlich für die vermehrte Kontraktion der aktivierten hepatischen Sternzellen (HSC). Dies führt zur portalen Hypertension. Die Hemmung der Rho-Kinase senkt über die Phosphorylierung der Myosinleichtketten

  11. ANALISIS FAKTOR-FAKTOR YANG MEMPENGARUHI AUDITOR SWITCHING PADA PERUSAHAAN MANUFAKTUR YANG TERDAFTAR DI BEI

    OpenAIRE

    -, OLIVIA

    2014-01-01

    2014 Penelitian ini bertujuan untuk menguji secara empiris opini going concern, reputasi KAP, financial distress, audit tenure, dan pergantian menajemen terhadap auditor switching. Auditor switching merupakan perilaku perpindahan auditor yang dilakukan oleh perusahaan akibat adanya kewajiban rotasi auditor. Pengumpulan data menggunakan purposive sampling terhadap perusahaan manufaktur yang terdaftar di Bursa Efek Indonesia (BEI) tahun 2008 sampai tahun 2012. Sebanyak 40 p...

  12. Perfusion computed tomography for diffuse liver diseases; Perfusions-CT bei diffusen Lebererkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, S.A.; Juchems, M.S. [Universitaetsklinikum Ulm, Klinik fuer Diagnostische und Interventionelle Radiologie, Ulm (Germany)

    2012-08-15

    Perfusion computed tomography (CT) has its main application in the clinical routine diagnosis of neuroradiological problems. Polyphase multi-detector spiral computed tomography is primarily used in liver diagnostics. The use of perfusion CT is also possible for the diagnostics and differentiation of diffuse hepatic diseases. The differentiation between cirrhosis and cirrhosis-like parenchymal changes is possible. It also helps to detect early stages of malignant tumors. However, there are some negative aspects, particularly that of radiation exposure. This paper summarizes the technical basics and possible applications of perfusion CT in cases of diffuse liver disease and weighs up the advantages and disadvantages of the examinations. (orig.) [German] Die Perfusions-CT hat ihren hauptsaechlichen Stellenwert bislang in der klinischen Routinediagnostik bei neuroradiologische Fragestellungen. In der Leberdiagnostik kommt v. a. die mehrphasige Multidetektor-Spiral-CT-Untersuchung zum Einsatz. Die Anwendung der Perfusions-CT ist auch bei der Diagnostik und Differenzierung diffuser Lebererkrankungen moeglich. Die Unterscheidung zwischen einer Leberzirrhose und zirrhoseaehnlichen Parenchymveraenderungen ist mit der Perfusions-CT moeglich. Ebenso liefert sie einen wertvollen Beitrag zur Diagnostik bei der Frueherkennung entstehender maligner Herdbefunde. Diesen Vorteilen stehen jedoch auch einige negative Aspekte gegenueber, insbesondere die relativ hohe Strahlenexposition. Die vorliegende Arbeit soll einen Ueberblick ueber die technischen Grundlagen und die Anwendungsmoeglichkeiten der Perfusions-CT bei diffusen Lebererkrankungen geben sowie die Vor- und Nachteile der Untersuchung gegeneinander abwaegen. (orig.)

  13. Precise orbit determination and point positioning using GPS, Glonass, Galileo and BeiDou

    Directory of Open Access Journals (Sweden)

    Tegedor J.

    2014-04-01

    Full Text Available State of the art Precise Point Positioning (PPP is currently based on dual-frequency processing of GPS and Glonass navigation systems. The International GNSS Service (IGS is routinely providing the most accurate orbit and clock products for these constellations, allowing point positioning at centimeter-level accuracy. At the same time, the GNSS landscape is evolving rapidly, with the deployment of new constellations, such as Galileo and BeiDou. The BeiDou constellation currently consists of 14 operational satellites, and the 4 Galileo In-Orbit Validation (IOV satellites are transmitting initial Galileo signals. This paper focuses on the integration of Galileo and BeiDou in PPP, together with GPS and Glonass. Satellite orbits and clocks for all constellations are generated using a network adjustment with observation data collected by the IGS Multi-GNSS Experiment (MGEX, as well as from Fugro proprietary reference station network. The orbit processing strategy is described, and orbit accuracy for Galileo and BeiDou is assessed via orbit overlaps, for different arc lengths. Kinematic post-processed multi-GNSS positioning results are presented. The benefits of multiconstellation PPP are discussed in terms of enhanced availability and positioning accuracy.

  14. Immunregulation bei aggressiver Parodontitis im Vergleich mit moderater chronischer Parodontitis und gesundem Parodontium

    OpenAIRE

    Schmidt, Jana

    2013-01-01

    Es ist davon auszugehen, dass Fehlfunktionen im Immunsystem mit der Ausprä-gung des Krankheitsbildes der aggressiven Parodontitis im Zusammenhang ste-hen. In dieser Arbeit sollen anhand klinischer, immunologischer und mikrobiologischer Untersuchungen ein immunologisches Risikoprofil bei Patienten mit aggressiver Parodontitis erschlossen, gegebenenfalls Unterschiede zur moderaten chronischen Parodontitis beleuchtet und explorativ Zusammenhänge zwischen immunologischen und mikrobiologischen Bef...

  15. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2010-04-01

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at the U.S. Department of Energy (DOE) Hanford site. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with requirements of 10 CFR 835, the DOE Laboratory Accreditation Program, the DOE Richland Operations Office, DOE Office of River Protection, DOE Pacific Northwest Office of Science, and Hanford’s DOE contractors. The dosimetry system is operated by the Pacific Northwest National Laboratory (PNNL) Hanford External Dosimetry Program which provides dosimetry services to PNNL and all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since its inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving significant changes to all chapters in the document. Revision

  16. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2011-04-04

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at the U.S. Department of Energy (DOE) Hanford site. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with requirements of 10 CFR 835, the DOE Laboratory Accreditation Program, the DOE Richland Operations Office, DOE Office of River Protection, DOE Pacific Northwest Office of Science, and Hanford’s DOE contractors. The dosimetry system is operated by the Pacific Northwest National Laboratory (PNNL) Hanford External Dosimetry Program which provides dosimetry services to PNNL and all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since its inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving significant changes to all chapters in the document. Revision

  17. Dosimetry in nuclear power plants; Dosimetria en centrales nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Lastra B, J. A. [CFE, Central Laguna Verde, Km. 42.5 Carretera Cardel-Nautla, Veracruz (Mexico)

    2008-12-15

    To control the occupationally exposed personnel dose working at the Laguna Verde nuclear power plant, two types of dosemeters are used, the thermoluminescent (TLD) which is processed monthly, and the direct reading dosemeter that is electronic and works as daily control of personal dose. In the case of the electronic dosemeters of direct reading conventional, the readings and dose automatic registers and the user identity to which he was assigned to each dosemeter was to carry out the restricted area exit. In activities where the ionizing radiation sources are not fully characterized, it is necessary to relocate the personal dosemeter or assigned auxiliary dosemeters (TLDs and electronics) to determine the dose received by the user to both whole body and in any specific area of it. In jobs more complicated are used a tele dosimetry system where the radiation protection technician can be monitoring the user dose to remote control, the data transmission is by radio. The dosimetry activities are documented in procedures that include dosemeter inventories realization, the equipment and dosemeters calibration, the dosimetry quality control and the discrepancies investigation between the direct reading and TLD systems. TLD dosimetry to have technical expertise in direct and indirect dosimetry and two technicians in TLD dosimetry; electronic dosimetry to have 4 calibration technicians. For the electronic dosemeters are based on a calibrator source of Cesium-137. TLD dosemeters to have an automatic radiator, an automatic reader which can read up to 100 TLD dosemeters per hour and a semiautomatic reader. To keep the equipment under a quality process was development a process of initial entry into service and carried out a periodic verification of the heating cycles. It also has a maintenance contract for the equipment directly with the manufacturer to ensure their proper functioning. The vision in perspective of the dosimetry services of Laguna Verde nuclear power plant

  18. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2007-03-12

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program (HEDP) which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee (HPDAC) which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. Rev. 0 marks the first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database. Revision numbers that are whole numbers reflect major revisions typically involving changes to all chapters in the document. Revision numbers that include a decimal fraction reflect minor revisions, usually restricted to selected chapters or selected pages in the document. Revision Log: Rev. 0 (2/25/2005) Major revision and expansion. Rev. 0.1 (3/12/2007) Minor

  19. Macroscopic to Microscopic Scales of Particulate Dosimetry: From Source to Fate in the Body

    Science.gov (United States)

    Additional perspective with regards to particle dosimetry is achieved by exploring dosimetry across a range of scales from macroscopic to microscopic in scope. Typically, one thinks of dosimetry as what happens when a particle is inhaled, where it is deposited, and how it is clea...

  20. Zeitlicher Verlauf der avaskulären Nekrose des Hüftkopfes bei Patienten mit Pemphigus vulgaris.

    Science.gov (United States)

    Balighi, Kamran; Daneshpazhooh, Maryam; Aghazadeh, Nessa; Saeidi, Vahide; Shahpouri, Farzam; Hejazi, Pardis; Chams-Davatchi, Cheyda

    2016-10-01

    Pemphigus vulgaris (PV) wird in der Regel mit systemischen Corticosteroiden und Immunsuppressiva behandelt. Avaskuläre Nekrose (AVN) des Hüftkopfes ist eine gut bekannte schwerere Komplikation einer Corticosteroid-Therapie. Die Charakteristika dieser schweren Komplikation bei PV sind nach wie vor unbekannt. Nicht kontrollierte, retrospektive Untersuchung aller PV-bedingten AVN-Fälle, die in einer iranischen Klinik für bullöse Autoimmunerkrankungen zwischen 1985 und 2013 diagnostiziert wurden. Anhand der Krankenakten von 2321 untersuchten PV-Patienten wurden 45 Fälle (1,93 %) von femoraler AVN identifiziert. Dreißig davon waren Männer. Das mittlere Alter bei der Diagnose der AVN betrug 47,4 ± 14,2 Jahre. Der mittlere Zeitraum zwischen der Diagnose des PV und dem Einsetzen der AVN lag bei 25,3 ± 18,3 Monaten. Mit Ausnahme von acht Fällen (17,8 %) setzte die AVN bei der Mehrheit der Patienten innerhalb von drei Jahren nach Diagnose des PV ein. Die mittlere kumulative Dosis von Prednisolon bei Patienten mit AVN betrug 13.115,8 ± 7041,1 mg. Zwischen der Prednisolon-Gesamtdosis und dem Zeitraum bis zum Einsetzen der AVN bestand eine starke Korrelation (p = 0,001). Bei Patienten mit Alendronateinnahme in der Vorgeschichte war dieser Zeitraum signifikant kürzer (p = 0,01). Die AVN ist eine schwere Komplikation einer Corticosteroid-Behandlung bei Patienten mit PV. Sie wird bei 2 % der Patienten beobachtet und tritt vor allem in den ersten drei Behandlungsjahren auf. Bei Patienten, die höhere Dosen von Prednisolon erhalten, setzt die AVN tendenziell früher ein. © 2016 Deutsche Dermatologische Gesellschaft (DDG). Published by John Wiley & Sons Ltd.

  1. Cardiac MRI in suspected myocarditis; MRT des Herzens bei Verdacht auf Myokarditis

    Energy Technology Data Exchange (ETDEWEB)

    Rieker, O.; Oberholzer, K.; Kreitner, K.F.; Thelen, M. [Klinik fuer Radiologie der Johannes Gutenberg-Univ. Mainz (Germany); Mohrs, O. [Klinik fuer Radiologie der Johannes Gutenberg-Univ. Mainz (Germany); Cardioangiologisches Centrum Bethanien, Frankfurt (Germany)

    2002-12-01

    Purpose: To evaluate the potential of ECG-gated breath-hold MRI in diagnosing acute myocardidits. Material and methods: Cardiac MRI was performed on 21 consecutive patients with suspected myocarditis. ECG-gated breath-hold T2-weighted images with fat suppression were acquired in 3 standard views. T1-weighted imaging (FLASH) was performed 10 min after IV administration of Gd-DTPA. Laboratory data included creatine kinase, troponin T and serological tests, ECG findings and echocardiography. Imaging findings were retrospectively compared to the discharge diagnoses. Signal alterations were semiquantitatively classified. Results: Acute myocarditis was diagnosed in 9 patients and cardiac sarcoidosis in 2 patients. Late enhancement was observed in 4 patients with acute myocarditis and in both patients with cardiac sarcoidosis. Semiquantitative evaluation revealed 9 true positive, 9 true negative, 1 false positive and 2 false negative results. Conclusion: Cardiac MRI has the potential to detect acute myocarditis and to diagnose cardiac sarcoidosis. Late enhancement of Gd-DTPA can be found in both viral myocarditis and cardiac sarcoidosis. (orig.) [German] Ziel: Beurteilung des diagnostischen Potenzials der MRT des Herzens bei Verdacht auf akute Myokarditis. Material und Methoden: 21 konsekutive Patienten mit Verdacht auf Myokarditis wurden mit einem standardisierten Protokoll untersucht. Zunaechst wurden T{sub 2}-gewichtete, EKG-getriggerte fettsupprimierte Sequenzen in den 3 Standardebenen angefertigt. 10 Minuten nach intravenoeser Injektion von GD-DTPA wurden T{sub 1}-gewichtete TurboFLASH-Sequenzen angefertigt. Von allen Patienten wurden EKG, Echokardiographie und die Laborbefunde einschliesslich Creatinin-Kinase, Troponin T und der Infektionsserologie protokolliert. Das Ausmass der Signalveraenderungen im MRT wurde semiquantitativ klassifiziert. Die Ergebnisse der MRT wurden retrospektiv mit den Entlassungsdiagnosen korreliert. Ergebnisse: Bei 9 Patienten lag nach

  2. PET in diagnosing exocrine pancreatic cancer; PET bei Tumoren des exokrinen Pankreas

    Energy Technology Data Exchange (ETDEWEB)

    Bares, R.; Besenfelder, H.; Dohmen, B.M. [Abt. Nuklearmedizin, Radiologische Klinik des Universitaetsklinikums Tuebingen (Germany)

    2003-06-01

    Despite dramatic improvements in diagnostic imaging (ultrasonography, in particular endoscopic ultrasound, CT, MRI) treatment results of pancreatic cancer are still poor. Due to the lack of early symptoms, most tumors are diagnosed at an advanced stage of disease which excludes curative surgical treatment. FDG-PET has been shown to be effective in detecting pancreatic cancer as well as differentiating benign from malignant pancreatic tumors. Results might be further improved by applying quantitative analyses, in particular kinetic modelling of FDG metabolism. Nevertheless false negative as well as false positive findings may occur. Small lesions (lymphnode or liver metastases < 1 cm) might be missed, furthermore hyperglycemia often present in patients with pancreatic disease might reduce tumor uptake and subsequently tumor detectability by PET. False positive findings were reported in active pancreatitis and some benign tumors. Although PET proved to be superior to CT or ERCP in detecting cancer, clinical relevance of PET is limited due to the absence of therapeutic consequences to be derived from PET. As a consequence PET should only be used in patients with equivocal findings of morphological imaging (CT, ERCP) who are potential candidates for surgical treatment. (orig.) [German] Trotz verbesserter diagnostischer Moeglichkeiten (endoskopischer Ultraschall, Spiral-CT, MRT) sind die Behandlungsergebnisse bei Tumoren des exokrinen Pankreas nach wie vor unbefriedigend. Aufgrund der spaet einsetzenden klinischen Symptomatik wird die Diagnose meist erst bei lokaler Inoperabilitaet gestellt. Die FDG-PET has sich sowohl im Nachweis von Pankreaskarzinomen als auch bei der Differenzialdiagnose pankreatischer Raumforderungen bewaehrt und den etablierten bildgebenden Verfahren (Ultraschall, CT) als ueberlegen erwiesen. Weitere Verbesserungen erscheinen durch absolute Quantifizierung der FDG-Kinetik moeglich. Dennoch koennen falsch negative wie auch falsch positive Ergebnisse

  3. Trends of personal dosimetry at atomic power plants

    Energy Technology Data Exchange (ETDEWEB)

    Yamamura, Seini [Fuji Electric Co. Ltd., Tokyo Factory, Radiation Equipment Department, Tokyo (Japan)

    1998-12-31

    The individual dosimetry at the atomic power station is sorted for monthly dosimetry, daily dosimetry and special job dosimetry in high dose circumstance. Film badge (passive dosimeter) can measure gamma dose, beta dose and neutron dose respectively lower than about 0.1 mSv. While workers are in the radiation controlled area, they have to wear the dosimeters and the individual dose is accumulated for every one month. Recently the Silicon semiconductors detecting beta ray and neutron have been developed. With microcircuit technology and these new sensors, new multiple function dosimeter of the card size had been put to practical use. The result of dose measurement obtained by the electronic dosimeter is consistent well with the measurement of usual film badge and new dosimeter can determine the dose as low as 0.01 mSv. The result is stored in the non-volatile memory in the electronic personal dosimeter and held for more than one year without the power supply. The function to read data directly from the memory improves the reliability of the data protection. The realization of the unified radiation control system that uses the electronic personal dosimeter for monthly dosimetry is expected. (J.P.N.)

  4. Millimeter wave dosimetry of human skin.

    Science.gov (United States)

    Alekseev, S I; Radzievsky, A A; Logani, M K; Ziskin, M C

    2008-01-01

    To identify the mechanisms of biological effects of mm waves it is important to develop accurate methods for evaluating absorption and penetration depth of mm waves in the epidermis and dermis. The main characteristics of mm wave skin dosimetry were calculated using a homogeneous unilayer model and two multilayer models of skin. These characteristics included reflection, power density (PD), penetration depth (delta), and specific absorption rate (SAR). The parameters of the models were found from fitting the models to the experimental data obtained from measurements of mm wave reflection from human skin. The forearm and palm data were used to model the skin with thin and thick stratum corneum (SC), respectively. The thin SC produced little influence on the interaction of mm waves with skin. On the contrary, the thick SC in the palm played the role of a matching layer and significantly reduced reflection. In addition, the palmar skin manifested a broad peak in reflection within the 83-277 GHz range. The viable epidermis plus dermis, containing a large amount of free water, greatly attenuated mm wave energy. Therefore, the deeper fat layer had little effect on the PD and SAR profiles. We observed the appearance of a moderate SAR peak in the therapeutic frequency range (42-62 GHz) within the skin at a depth of 0.3-0.4 mm. Millimeter waves penetrate into the human skin deep enough (delta = 0.65 mm at 42 GHz) to affect most skin structures located in the epidermis and dermis.

  5. Artificial neural networks in neutron dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Vega C, H.R.; Hernandez D, V.M.; Manzanares A, E.; Mercado, G.A.; Perales M, W.A.; Robles R, J.A. [Unidades Academicas de Estudios Nucleares, UAZ, A.P. 336, 98000 Zacatecas (Mexico); Gallego, E.; Lorente, A. [Depto. de Ingenieria Nuclear, Universidad Politecnica de Madrid, (Spain)

    2005-07-01

    An artificial neural network has been designed to obtain the neutron doses using only the Bonner spheres spectrometer's count rates. Ambient, personal and effective neutron doses were included. 187 neutron spectra were utilized to calculate the Bonner count rates and the neutron doses. The spectra were transformed from lethargy to energy distribution and were re-binned to 31 energy groups using the MCNP 4C code. Re-binned spectra, UTA4 response matrix and fluence-to-dose coefficients were used to calculate the count rates in Bonner spheres spectrometer and the doses. Count rates were used as input and the respective doses were used as output during neural network training. Training and testing was carried out in Mat lab environment. The artificial neural network performance was evaluated using the {chi}{sup 2}- test, where the original and calculated doses were compared. The use of Artificial Neural Networks in neutron dosimetry is an alternative procedure that overcomes the drawbacks associated in this ill-conditioned problem. (Author)

  6. IMBA Expert: internal dosimetry made simple.

    Science.gov (United States)

    Birchall, A; Puncher, M; James, A C; Marsh, J W; Jarvis, N S; Peace, M S; Davis, K; King, D J

    2003-01-01

    In 1997, a collaboration between British Nuclear Fuels plc (BNFL), Westlakes Research Institute and NRPB started, with the aim of producing IMBA (Integrated Modules for Bioassay Analysis), a suite of software modules that implement the new ICRP models for estimation of intakes and doses. This was partly in response to new UK regulations, and partly due to the requirement for a unified approach in estimating intakes and doses from bioassay measurements within the UK. Over the past 5 years, the IMBA modules have been developed further, have gone through extensive quality assurance, and are now used for routine dose assessment by approved dosimetry services throughout the UK. More recently, interest in the IMBA methodology has been shown by the United States Department of Energy (USDOE), and in 2001 an ambitious project to develop a software package (IMBA Expert USDOE Edition) which would meet the requirements of all of the major USDOE sites began. Interest in IMBA Expert is now being expressed in many other countries. The aim of this paper is to outline the origin and evolution of the IMBA modules (the past); to describe the full capabilities of the current IMBA Expert system (the present) and to indicate possible future directions in terms of capabilities and availability (the future).

  7. Calibration facility for environment dosimetry instruments

    Energy Technology Data Exchange (ETDEWEB)

    Bercea, Sorin; Celarel, Aurelia; Cenusa, Constantin [Horia Hulubei National Institute for Physics and Nuclear Engineering, 30 Reactorului St, Magurele, Jud Ilfov, P.O.B. MG-6, RO-077125 (Romania)

    2013-12-16

    In the last ten years, the nuclear activities, as well as the major nuclear events (see Fukushima accident) had an increasing impact on the environment, merely by contamination with radioactive materials. The most conferment way to quickly identify the presence of some radioactive elements in the environment, is to measure the dose-equivalent rate H. In this situation, information concerning the values of H due only to the natural radiation background must exist. Usually, the values of H due to the natural radiation background, are very low (∼10{sup −9} - 10{sup −8} Sv/h). A correct measurement of H in this range involve a performing calibration of the measuring instruments in the measuring range corresponding to the natural radiation background lead to important problems due to the presence of the natural background itself the best way to overlap this difficulty is to set up the calibration stand in an area with very low natural radiation background. In Romania, we identified an area with such special conditions at 200 m dept, in a salt mine. This paper deals with the necessary requirements for such a calibration facility, as well as with the calibration stand itself. The paper includes also, a description of the calibration stand (and images) as well as the radiological and metrological parameters. This calibration facilities for environment dosimetry is one of the few laboratories in this field in Europe.

  8. Beta-particle dosimetry in radiation synovectomy

    Energy Technology Data Exchange (ETDEWEB)

    Johnson, L.S. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Nuclear Engineering; Yanch, J.C. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Nuclear Engineering; Shortkroff, S. [Department of Orthopedic Surgery, Brigham and Women`s Hospital, Boston, MA (United States); Barnes, C.L. [Department of Orthopedic Surgery, Brigham and Women`s Hospital, Boston, MA (United States); Spitzer, A.I. [Department of Orthopedic Surgery, Brigham and Women`s Hospital, Boston, MA (United States); Sledge, C.B. [Department of Orthopedic Surgery, Brigham and Women`s Hospital, Boston, MA (United States)

    1995-09-01

    Beta-particle dosimetry of various radionuclides used in the treatment of rheumatoid arthritis was estimated using Monte Carlo radiation transport simulation coupled with experiments using reactor-produced radionuclides and radiachromic film dosimeters inserted into joint phantoms and the knees of cadavers. Results are presented as absorbed dose factors (cGy-cm{sup 2}/MBq-s) versus depth in a mathematical model of the rheumatoid joint which includes regions of bone, articular cartilage, joint capsule, and tissue (synovium) found in all synovial joints. The factors can be used to estimate absorbed dose and dose rate distributions in treated joints. In particular, guidance is provided for those interested in (a) a given radionuclide`s therapeutic range, (b) the amount of radioactivity to administer on a case-by-case basis, (c) the expected therapeutic dose to synovium, and (d) the radiation dose imparted to other, nontarget components in the joint, including bone and articular cartilage. (orig.). With 6 figs., 6 tabs.

  9. Dosimetry of radioiodine for embryo and fetus

    Energy Technology Data Exchange (ETDEWEB)

    Berkovski, V.; Eckerman, K.F.; Phipps, A.W.; Nosske, D

    2003-07-01

    This paper discusses the biokinetic and dosimetric models adopted in ICRP Publication 88 for the evaluation of fetal doses resulting from maternal intakes of radioiodine. The biokinetic model is used to simulate the behaviour of iodine in both the mother and the fetus. Such simulations provide the basis for the estimation of the dose to the embryo and determine the distribution of maternal iodine at the beginning of the fetal period. The model considers iodine to accumulate in the fetal thyroid from the 11th week. The dose to the fetus delivered following birth is evaluated with the biokinetic and dosimetric models described in ICRP Publication 67. Although a substantial fraction of the emitted energy of electrons and photons is less than 10 keV, conventionally assumed to be non-penetrating radiation, these emissions can escape the small fetal thyroid. Absorbed fractions for both self-dose and crossfire were evaluated for the requirements of radioiodine dosimetry in ICRP Publication 88. (author)

  10. Oxygen measurements to improve singlet oxygen dosimetry

    Science.gov (United States)

    Kim, Michele M.; Penjweini, Rozhin; Ong, Yi Hong; Finlay, Jarod C.; Zhu, Timothy C.

    2017-02-01

    Photodynamic therapy (PDT) involves interactions between the three main components of light fluence, photosensitizer concentration, and oxygenation. Currently, singlet oxygen explicit dosimetry (SOED) has focused on the first two of these components. The macroscopic model to calculate reacted singlet oxygen has previously involved a fixed initial ground state oxygen concentration. A phosphorescence-based oxygen probe was used to measure ground state oxygen concentration throughout treatments for mice bearing radioactively induced fibroscarcoma tumors. Photofrin-, BPD-, and HPPH-mediated PDT was performed on mice. Model-calculated oxygen and measured oxygen was compared to evaluate the macroscopic model as well as the photochemical parameters involved. Oxygen measurements at various depths were compared to calculated values. Furthermore, we explored the use of noninvasive diffuse correlation spectroscopy (DCS) to measure tumor blood flow changes in response to PDT to improve the model calculation of reacted singlet oxygen. Mice were monitored after treatment to see the effect of oxygenation on long-term recurrence-free survival as well as the efficacy of using reacted singlet oxygen as a predictive measure of outcome. Measurement of oxygenation during treatment helps to improve SOED as well as confirm the photochemical parameters involved in the macroscopic model. Use of DCS in predicting oxygenation changes was also investigated.

  11. Reactor dosimetry and RPV life management

    Energy Technology Data Exchange (ETDEWEB)

    Belousov, S.; Ilieva, K.; Mitev, M. [Inst. for Nuclear Research and Nuclear Energy, Bulgarian Academy of Sciences, Tsarigradsko 72, 1784 Sofia (Bulgaria)

    2011-07-01

    Reactor dosimetry (RD) is a tool that provides data for neutron fluence accumulated over the reactor pressure vessel (RPV) during the reactor operation. This information, however, is not sufficient for RPV lifetime assessment. The life management of RPV is a multidisciplinary task. To assess whether the RPV steel properties at the current stage (for actual accumulated neutron fluence) of reactor operation are still 'safe enough,' the dependence of material properties on the fluence must be known; this is a task for material science (MS). Moreover, the mechanical loading over the RPV during normal operation and accidence have to be known, as well, for evaluation, if the RPV material integrity in this loading condition and existing cracks is provided. The crack loading path in terms of stress intensity factor is carried out by structural analyses (SA). Pressure and temperature distribution over RPV used in these analyses are obtained from a thermal hydraulic (TH) calculation. The conjunction of RD and other disciplines in RPV integrity assessment is analyzed in accordance with the FFP (fitness for purpose) approach. It could help to improve the efficiency in multi-disciplinary tasks solutions. (authors)

  12. Calibration facility for environment dosimetry instruments

    Science.gov (United States)

    Bercea, Sorin; Celarel, Aurelia; Cenusa, Constantin

    2013-12-01

    In the last ten years, the nuclear activities, as well as the major nuclear events (see Fukushima accident) had an increasing impact on the environment, merely by contamination with radioactive materials. The most conferment way to quickly identify the presence of some radioactive elements in the environment, is to measure the dose-equivalent rate H. In this situation, information concerning the values of H due only to the natural radiation background must exist. Usually, the values of H due to the natural radiation background, are very low (˜10-9 - 10-8 Sv/h). A correct measurement of H in this range involve a performing calibration of the measuring instruments in the measuring range corresponding to the natural radiation background lead to important problems due to the presence of the natural background itself the best way to overlap this difficulty is to set up the calibration stand in an area with very low natural radiation background. In Romania, we identified an area with such special conditions at 200 m dept, in a salt mine. This paper deals with the necessary requirements for such a calibration facility, as well as with the calibration stand itself. The paper includes also, a description of the calibration stand (and images) as well as the radiological and metrological parameters. This calibration facilities for environment dosimetry is one of the few laboratories in this field in Europe.

  13. Implementation of IMRT and VMAT using Delta4 phantom and portal dosimetry as dosimetry verification tools

    Energy Technology Data Exchange (ETDEWEB)

    Daci, Lulzime, E-mail: lulzime.daci@nodlandssykehuset.no [Nordland Hospital Trust, Bodø (Norway); Malkaj, Partizan, E-mail: malkaj-p@hotmail.com [Faculty of Mathematics Engineering and Physics Engineering, Polytechnic University of Tirana (Albania)

    2016-03-25

    In this study we analyzed and compared the dose distribution of different IMRT and VMAT plans with the intent to provide pre-treatment quality assurance using two different tools. Materials/Methods: We have used the electronic portal imaging device EPID after calibration to dose and correction for the background offset signal and also the Delta4 phantom after en evaluation of angular sensitivity. The Delta4 phantom has a two-dimensional array with ionization chambers. We analyzed three plans for each anatomical site calculated by Eclipse treatment planning system. The measurements were analyzed using γ-evaluation method with passing criteria 3% absolute dose and 3 mm distance to agreement (DTA). For all the plans the range of score has been from 97% to 99% for gantry fixed at 0° while for rotational planes there was a slightly decreased pass rates and above 95%. Point measurement with a ionization chamber were done in additional to see the accuracy of portal dosimetry and to evaluate the Delta4 device to various dose rates. Conclusions: Both Delt4 and Portal dosimetry shows good results between the measured and calculated doses. While Delta4 is more accurate in measurements EPID is more time efficient. We have decided to use both methods in the first steps of IMRT and VMAT implementation and later on to decide which of the tools to use depending on the complexity of plans, how much accurate we want to be and the time we have on the machine.

  14. Implementation of IMRT and VMAT using Delta4 phantom and portal dosimetry as dosimetry verification tools

    Science.gov (United States)

    Daci, Lulzime; Malkaj, Partizan

    2016-03-01

    In this study we analyzed and compared the dose distribution of different IMRT and VMAT plans with the intent to provide pre-treatment quality assurance using two different tools. Materials/Methods: We have used the electronic portal imaging device EPID after calibration to dose and correction for the background offset signal and also the Delta4 phantom after en evaluation of angular sensitivity. The Delta4 phantom has a two-dimensional array with ionization chambers. We analyzed three plans for each anatomical site calculated by Eclipse treatment planning system. The measurements were analyzed using γ-evaluation method with passing criteria 3% absolute dose and 3 mm distance to agreement (DTA). For all the plans the range of score has been from 97% to 99% for gantry fixed at 0° while for rotational planes there was a slightly decreased pass rates and above 95%. Point measurement with a ionization chamber were done in additional to see the accuracy of portal dosimetry and to evaluate the Delta4 device to various dose rates. Conclusions: Both Delt4 and Portal dosimetry shows good results between the measured and calculated doses. While Delta4 is more accurate in measurements EPID is more time efficient. We have decided to use both methods in the first steps of IMRT and VMAT implementation and later on to decide which of the tools to use depending on the complexity of plans, how much accurate we want to be and the time we have on the machine.

  15. Einfluss einer kohlenhydratarmen Fütterung auf den Stickstoff-Stoffwechsel und die Kalziumverfügbarkeit bei Ratten

    OpenAIRE

    Frommelt, Lena

    2015-01-01

    Kohlenhydratarme Diäten werden in der Humanmedizin zur Gewichtsreduktion bei Adipositas eingesetzt. Als ketogene Diät (KD) wird eine kohlenhydratarme Diät mit hohem Fettgehalt (low-carbohydrate, high-fat; LCHF-Diät) bei verschiedenen Erkrankungen, wie der Epilepsie bei Kindern oder einem Pyruvatdehydrogenase-Mangel, eingesetzt. LCHF-Diäten, die sicher eine Ketose erzeugen, haben zusätzlich zum hohen Fettgehalt und geringen Kohlenhydratgehalt einen sehr niedrigen Proteingehalt. Als eine der Ne...

  16. Laterale 10-fach-Biopsie der Prostata liefert bei Karzinomverdacht überlegene Detektionsraten

    Directory of Open Access Journals (Sweden)

    von Knobloch R

    2012-01-01

    Full Text Available Einleitung:Die Sextantenbiopsie der Prostata ist für eine verlässliche Karzinomdiagnostik nicht ausreichend. Vielerorts werden bereits bei der Erstbiopsie 12 Stanzen entnommen. In einer großen Serie von 10-fach-Biopsien unter bilateraler lokaler Leitungsanästhesie, wie bereits 2002 publiziert [1], überprüften wir die Qualität unserer Technik als Standard für die Erstbiopsie. Methode:Zwischen April 2005 und Dezember 2007 führten wir bei 736 Männern (Durchschnittsalter 67,5 ± 8,39 Jahre die Erstbiopsie der Prostata durch. Indikation für die Biopsie war entweder ein erhöhter PSA-Wert oder ein auffälliger Tastbefund. Bei allen Männern erfolgte die Biopsie der Prostata unter bilateraler lokaler Leitungsanästhesie. Es wurden nur Proben aus der peripheren Zone der Prostata unter transrektaler Ultraschallkontrolle entnommen. Ergebnisse:Durch die Biopsie wurde in 372 von 736 Fällen (50,5 % ein Karzinom identifiziert. Die Karzinomdetektionsrate war proportional zum PSA-Wert und indirekt proportional zum Organvolumen. Es zeigte sich eine eindeutige Korrelation zwischen der Anzahl positiver Stanzen bei der Biopsie mit dem pathologischen Stadium des Prostatektomiepräparates. 12 Männer (1,6 % mussten wegen akuter Prostatitis und 5 (0,7 % wegen rektaler Blutung wieder ins Krankenhaus eingewiesen werden. Von den 182 Patienten des Untersuchers R. v. K. wurde der durchschnittliche Schmerz der Biopsie mit 1,69 von maximal 10 angegeben. Die Detektions- und Komplikationsraten dieser Biopsietechnik unterschieden sich nicht nach Durchführung von Assistenz- oder Fachärzten. Schlussfolgerung: Die präsentierte Biopsietechnik liefert mit nur 10 Stanzen eine überlegene Detektionsrate und eine geringe Rate an Komplikationen. Sie sollte als Basis für die Definition eines Standards für die Erstbiopsie der Prostata bei Karzinomverdacht dienen.

  17. Stochastic modeling of triple-frequency BeiDou signals: estimation, assessment and impact analysis

    Science.gov (United States)

    Li, Bofeng

    2016-07-01

    Stochastic models are important in global navigation satellite systems (GNSS) estimation problems. One can achieve reliable ambiguity resolution and precise positioning only by use of a suitable stochastic model. The BeiDou system has received increased research focus, but based only on empirical stochastic models from the knowledge of GPS. In this paper, we will systematically study the estimation, assessment and impacts of a triple-frequency BeiDou stochastic model. In our estimation problem, a single-difference, geometry-free functional model is used to extract pure random noise. A very sophisticated structure of unknown variance matrix is designed to allow the estimation of satellite-specific variances, cross correlations between two arbitrary frequencies, as well as the time correlations for phase and code observations per frequency. In assessing the stochastic models, six data sets with four brands of BeiDou receivers on short and zero-length baselines are processed, and the results are compared. In impact analysis of stochastic model, the performance of integer ambiguity resolution and positioning are numerically demonstrated using a realistic stochastic model. The results from ultrashort (shorter than 10 m) and zero-length baselines indicate that BeiDou stochastic models are affected by both observation and receiver brands. The observation variances have been modeled by an elevation-dependent function, but the modeling errors for geostationary earth orbit (GEO) satellites are larger than for inclined geosynchronous satellite orbit (IGSO) and medium earth orbit (MEO) satellites. The stochastic model is governed by both the internal errors of the receiver and external errors at the site. Different receivers have different capabilities for resisting external errors. A realistic stochastic model is very important for achieving ambiguity resolution with a high success rate and small false alarm and for determining realistic variances for position estimates. To

  18. Kinematic MRI of the cervical spine in patients with degenerative disease; Kinematische MRT bei degenerativen Halswirbelsaeulenveraenderungen

    Energy Technology Data Exchange (ETDEWEB)

    Muhle, C. [Klinik fuer Radiologische Diagnostik, Christian-Albrechts-Universitaet, Kiel (Germany); Wiskirchen, J. [Klinik fuer Radiologische Diagnostik, Christian-Albrechts-Universitaet, Kiel (Germany); Brinkmann, G. [Klinik fuer Radiologische Diagnostik, Christian-Albrechts-Universitaet, Kiel (Germany); Falliner, A. [Klinik fuer Orthopaedie, Christian-Albrechts-Universitaet, Kiel (Germany); Weinert, D. [Klinik fuer Neurochirurgie, Christian-Albrechts-Universitaet, Kiel (Germany); Reuter, M. [Klinik fuer Radiologische Diagnostik, Christian-Albrechts-Universitaet, Kiel (Germany); Heller, M. [Klinik fuer Radiologische Diagnostik, Christian-Albrechts-Universitaet, Kiel (Germany)

    1995-08-01

    Kinematic MRI of the cervical spine was done from 50 of inclination to 30 of reclination. Depending on the maximum inclination and reclination the range of motion was divided into 9 equal angle positions. At each angle position sagittal T{sub 2}{sup `} weighted gradient echo sequences were performed. In relation to the neutral position a physiological narrowing of the ventral epidural space was seen in healthy volunteers at inclination (50 ) in up to 50% and respectively widening at reclination (30 ) in up to 10%. An increase of spinal canal stenosis or even spinal cord compression was seen at inclination in 5 patients (22%) and in 15 patients (65%) at reclination. No change of spinal canal stenosis was found in three patients (13%). (orig./MG) [Deutsch] Bei 23 Probanden und 23 Patienten mit degenerativen Veraenderungen der Halswirbelsaeule erfolgte nach Abschluss der statischen MRT-Untersuchung die Funktionsuntersuchung der Halswirbelsaeule von maximal 50 Anteflexion bis maximal 30 Retroflexion in bis zu 9 unterschiedlichen Flexionsstellungen. In jeder Flexionsstellung wurden sagittale Aufnahmen in T{sub 2}{sup `}-gewichteten Gradienten-Echo-Sequenzen angefertigt. In der Probandengruppe konnten bei max. Anteflexion (50 ) eine physiologische Verschmaelerung des ventralen Subarachnoidalraumes von ca. 50% gegenueber der horizontalen Ausgangstellung (0 ) und eine Erweiterung des ventralen Subarachnoidalraumes von ca. 10% waehrend max. Retroflexion (30 ) festgestellt werden. Die Funktionsuntersuchungen zeigten bei 5 Patienten (22%) in Anteflexion und bei 15 Patienten (65%) in Retroflexion eine zunehmende Spinalkanalstenose bzw. Myelonkompression durch dorsale osteophytaere Randanbauten. Gegenueber der Ausgangsstellung war bei nur 3 Patienten (13%) eine Befundkonstanz zu beobachten. (orig./MG)

  19. Applied physics of external radiation exposure dosimetry and radiation protection

    CERN Document Server

    Antoni, Rodolphe

    2017-01-01

    This book describes the interaction of living matter with photons, neutrons, charged particles, electrons and ions. The authors are specialists in the field of radiation protection. The book synthesizes many years of experiments with external radiation exposure in the fields of dosimetry and radiation shielding in medical, industrial and research fields. It presents the basic physical concepts including dosimetry and offers a number of tools to be used by students, engineers and technicians to assess the radiological risk and the means to avoid them by calculating the appropriate shields. The theory of radiation interaction in matter is presented together with empirical formulas and abacus. Numerous numerical applications are treated to illustrate the different topics. The state of the art in radiation protection and dosimetry is presented in detail, especially in the field of simulation codes for external exposure to radiation, medical projects and advanced research. Moreover, important data spread in differ...

  20. RCT: Module 2.04, Dosimetry, Course 8769

    Energy Technology Data Exchange (ETDEWEB)

    Hillmer, Kurt T. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-08-11

    This course will introduce the types of instruments used to measure external and internal radiation to people. Dosimetry is the quantitative assessment of radiation received by the human body. Several types of dosimeters are used worldwide. This information is valuable to all radiological control personnel because dosimeters are the only direct method to measure and document personnel radiation exposure and ensure regulatory compliance with applicable limits. This course will cover dosimetry terms, Department of Energy (DOE) limits, Los Alamos National Laboratory (LANL) administrative guidelines, thermoluminescent dosimeters (TLDs), LANL dosimetry, and bioassay assessment methods. This course will prepare the student with the skills necessary for radiological control technician (RCT) qualification by passing quizzes, tests, and the RCT Comprehensive Phase 1, Unit 2 Examination (TEST 27566) and providing in-thefield skills.

  1. Development of 3D Slicer based film dosimetry analysis

    Science.gov (United States)

    Alexander, K. M.; Robinson, A.; Pinter, C.; Fichtinger, G.; Schreiner, L. J.

    2017-05-01

    Radiochromic film dosimetry has been widely adopted in the clinic as it is a convenient option for dose measurement and verification. Film dosimetry analysis is typically performed using expensive commercial software, or custom made scripts in Matlab. However, common clinical film analysis software is not transparent regarding what corrections/optimizations are running behind the scenes. In this work, an extension to the open-source medical imaging platform 3D Slicer was developed and implemented in our centre for film dosimetry analysis. This extension streamlines importing treatment planning system dose and film imaging data, film calibration, registration, and comparison of 2D dose distributions, enabling greater accessibility to film analysis and higher reliability.

  2. A practical three-dimensional dosimetry system for radiation therapy.

    Science.gov (United States)

    Guo, Pengyi; Adamovics, John; Oldham, Mark

    2006-10-01

    There is a pressing need for a practical three-dimensional (3D) dosimetry system, convenient for clinical use, and with the accuracy and resolution to enable comprehensive verification of the complex dose distributions typical of modern radiation therapy. Here we introduce a dosimetry system that can achieve this challenge, consisting of a radiochromic dosimeter (PRESAGE) and a commercial optical computed tomography (CT) scanning system (OCTOPUS). PRESAGE is a transparent material with compelling properties for dosimetry, including insensitivity of the dose response to atmospheric exposure, a solid texture negating the need for an external container (reducing edge effects), and amenability to accurate optical CT scanning due to radiochromic optical contrast as opposed to light-scattering contrast. An evaluation of the performance and viability of the PRESAGE/OCTOPUS, combination for routine clinical 3D dosimetry is presented. The performance of the two components (scanner and dosimeter) was investigated separately prior to full system test. The optical CT scanner has a spatial resolution of OCTOPUS system was evaluated with respect to a simple known 3D dose distribution, by comparison with GAFCHROMIC EBT film and the calculated dose from a commissioned planning system. The "measured" dose distribution in a cylindrical PRESAGE dosimeter (16 cm diameter and 11 cm height) was determined by optical-CT, using a filtered backprojection reconstruction algorithm. A three-way Gamma map comparison (4% dose difference and 4 mm distance to agreement), between the PRESAGE, EBT and calculated dose distributions, showed full agreement in measurable region of PRESAGE dosimeter (approximately 90% of radius). The EBT and PRESAGE distributions agreed more closely with each other than with the calculated plan, consistent with penumbral blurring in the planning data which was acquired with an ion chamber. In summary, our results support the conclusion that the PRESAGE optical

  3. Accuracy of helium accumulation fluence monitor for fast reactor dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Chikara; Aoyama, Takafumi [Power Reactor and Nuclear Fuel Development Corp., Oarai, Ibaraki (Japan). Oarai Engineering Center

    1998-03-01

    A helium (He) accumulation fluence monitor (HAFM) has been developed for fast reactor dosimetry. In order to evaluate the measurement accuracy of neutron fluence by the HAFM method, the HAFMs of enriched boron (B) and beryllium (Be) were irradiated in the Fast Neutron Source Reactor `YAYOI`. The number of He atoms produced in the HAFMs were measured and compared with the calculated values. As a result of this study, it was confirmed that the neutron fluence could be measured within 5 % by the HAFM method, and that met the required accuracy for fast reactor dosimetry. (author)

  4. Current state of the art brachytherapy treatment planning dosimetry algorithms.

    Science.gov (United States)

    Papagiannis, P; Pantelis, E; Karaiskos, P

    2014-09-01

    Following literature contributions delineating the deficiencies introduced by the approximations of conventional brachytherapy dosimetry, different model-based dosimetry algorithms have been incorporated into commercial systems for (192)Ir brachytherapy treatment planning. The calculation settings of these algorithms are pre-configured according to criteria established by their developers for optimizing computation speed vs accuracy. Their clinical use is hence straightforward. A basic understanding of these algorithms and their limitations is essential, however, for commissioning; detecting differences from conventional algorithms; explaining their origin; assessing their impact; and maintaining global uniformity of clinical practice.

  5. Thermoluminescence dosimetry of rare earth doped calcium aluminate phosphors

    Indian Academy of Sciences (India)

    K Madhukumar; K Rajendra Babu; K C Ajith Prasad; J James; T S Elias; V Padmanabhan; C M K Nair

    2006-04-01

    The thermoluminescence (TL) properties of calcium aluminate (CaAl2O4) doped with different rare earth ions have been studied and their suitability for radiation dosimetry applications is discussed. It is observed that monocalcium aluminate doped with cerium is a good dosimeter having linear response up to about 4 kGy of radiation doses. Dopant concentration of 0.25 mol% cerium gives maximum TL emission. The well-defined single peak observed at 295°C can be advantageously used for high temperature dosimetry applications.

  6. Hanford Internal Dosimetry Program Manual, PNL-MA-552

    Energy Technology Data Exchange (ETDEWEB)

    Carbaugh, Eugene H.; Bihl, Donald E.; Maclellan, Jay A.

    2009-09-24

    This manual is a guide to the services provided by the Hanford Internal Dosimetry Program (IDP), which is operated by the Pacific Northwest National Laboratory.( ) for the U.S. Department of Energy Richland Operations Office, Office of River Protection and their Hanford Site contractors. The manual describes the roles of and relationships between the IDP and the radiation protection programs of the Hanford Site contractors. Recommendations and guidance are also provided for consideration in implementing bioassay monitoring and internal dosimetry elements of radiation protection programs.

  7. Dosimetry of the mixed field irradiation facility CALIBAN

    Energy Technology Data Exchange (ETDEWEB)

    Trompier, F. [Institute for Radiological Protection and Nuclear Safety, 92265 Fontenay-aux-roses (France)], E-mail: francois.trompier@irsn.fr; Huet, C.; Medioni, R.; Robbes, I. [Institute for Radiological Protection and Nuclear Safety, 92265 Fontenay-aux-roses (France); Asselineau, B. [Institute of Radioprotection and Nuclear Safety, 13115 St Paul-Lez-Durance (France)

    2008-02-15

    The dosimetry of the experimental reactor CALIBAN was established for photon and neutron components, and the kerma variations were evaluated according to position (distance from the core, height, angle with the median room axis). Dosimetry was performed with TLD (Al{sub 2}O{sub 3}) for the photon component, and with passive silicon diodes, activation detectors (Au, In, Ni, Mg, Cu) and alanine pellets measured by EPR spectrometry for the neutron component. The neutron energy distribution was experimentally evaluated at various distances based on the activities measured at the activated foil using the SNAC2 software. It was then compared with those calculated with the Monte Carlo code MCNPX.

  8. Third conference on radiation protection and dosimetry. Program and abstracts

    Energy Technology Data Exchange (ETDEWEB)

    None

    1991-01-01

    This conference has been designed with the objectives of promoting communication among applied, research, regulatory, and standards personnel involved in radiation protection and providing them with sufficient information to evaluate their programs. To partly fulfill these objectives, a technical program consisting of more than 75 invited and contributed oral presentations encompassing all aspects of radiation protection has been prepared. General topics include external dosimetry, internal dosimetry, instruments, regulations and standards, accreditation and test programs, research advances, and applied program experience. This publication provides a summary of the technical program and a collection of abstracts of the oral presentations.

  9. Applicability of superheated drop (bubble) detectors to reactor dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    d`Errico, F.; Curzio, G. [Univ. degli Studi di Pisa (Italy). Dipt. di Costruzioni Meccaniche e Nucleari; Alberts, W.G. [Physikalisch-Technische Bundesanstalt, Braunschweig (Germany); Apfel, R.E.; Guldbakke, S. [Yale Univ., New Haven, CT (United States). Dept. of Mechanical Engineering

    1994-12-31

    The characteristics of superheated drop (bubble) detectors (SDD`s) have been reviewed with respect to the possible application of these devices in reactor dosimetry. In particular, their ability to measure neutrons in the presence of a high noise level, elevated temperatures and intense {gamma} background has been investigated. Based on these studies, the use of SDD`s is proposed for the monitoring and analysis of neutron emission from spent fuel assemblies. Finally, the possibility to employ these detectors in radiation protection dosimetry around power plants is discussed.

  10. 4D dosimetry and its applications to pre-treatment quality control and real-time in vivo dosimetry of VMAT treatments

    Science.gov (United States)

    Nordström, F.; Wetterstedt, S. af; Bäck, S. Å. J.

    2013-06-01

    In this study, a 4D dosimetry concept was developed. This concept included a method for calculation of 3D reference absorbed dose matrices at every control point of the delivery using a clinical treatment planning system (TPS). Further, the gamma evaluation method was extended to incorporate the 4th dimension of the TPS calculated dose distributions. The applications of the 4D dosimetry concept on pre-treatment quality control and real-time in vivo dosimetry were investigated.

  11. Subwavelength films for standoff radiation dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Alvine, Kyle J.; Bernacki, Bruce E.; Bennett, Wendy D.; Schemer-Kohrn, Alan L.; Suter, Jonathan D.

    2015-05-22

    We present optical subwavelength nanostructure architecture suitable for standoff radiation dosimetry with remote optical readout in the visible or infrared spectral regions. To achieve this, films of subwavelength structures are fabricated over several square inches via the creation of a 2D non-close packed (NCP) array template of radiation-sensitive polymeric nanoparticles, followed by magnetron sputtering of a metallic coating to form a 2D array of separated hemispherical nanoscale metallic shells. The nanoshells are highly reflective at resonance in the visible or infrared depending on design. These structures and their behavior are based on the open ring resonator (ORR) architecture and have their analog in resonant inductive-capacitive (LC) circuits, which display a resonance wavelength that is inversely proportional to the square root of the product of the inductance and capacitance. Therefore, any modification of the nanostructure material properties due to radiation alters the inductive or capacitive behavior of the subwavelength features, which in turn changes their optical properties resulting in a shift in the optical resonance. This shift in resonance may be remotely interrogated actively using either laser illumination or passively by hyperspectral or multispectral sensing with broadband illumination. These structures may be designed to be either anisotropic or isotropic, which can also offer polarization-sensitive interrogation. We present experimental measurements of a radiation induced shift in the optical resonance of a subwavelength film after exposure to an absorbed dose of gamma radiation from 2 Mrad up to 62 Mrad demonstrating the effect. Interestingly the resonance shift is non-monotonic for this material system and possible radiation damage mechanisms to the nanoparticles are discussed.

  12. Tenth ORNL Personnel Dosimetry Intercomparison Study

    Energy Technology Data Exchange (ETDEWEB)

    Swaja, R.E.; Chou, T.L.; Sims, C.S.; Greene, R.T.

    1985-03-01

    The Tenth Personnel Dosimetry Intercomparison Study was conducted at the Oak Ridge National Laboratory during April 9-11, 1984. Dosemeter badges from 31 participating organizations were mounted on 40cm Lucite phantoms and exposed to a range of dose equivalents which could be encountered during routine personnel monitoring in mixed radiation fields. The Health Physics Research Reactor served as the only source of radiation for eight of the ten irradiations which included a low (approx. 0.50 mSv) and high (approx. 10.00 mSv) neutron dose equivalent run for each of four shield conditions. Two irradiations were also conducted for which concrete- and Lucite-shield reactor irradiations were gamma-enhanced using a /sup 137/Cs source. Results indicated that some participants had difficulty obtaining measurable indication of neutron and gamma exposures at dose equivalents less than about 0.50 mSv and 0.20 mSv, respectively. Albedo dosemeters provided the best overall accuracy and precision for the neutron measurements. Direct interaction TLD systems showed significant variation in accuracy with incident spectrum, and threshold neutron dosemeters (film and recoil track) underestimated reference values by more than 50%. Gamma dose equivalents estimated in the mixed fields were higher than reference values with TL gamma dosemeters generally yielding more accurate results than film. Under the conditions of this study in which participants had information concerning exposure conditions and radiation field characteristics prior to dosemeter evaluation, only slightly more than half of all reported results met regulatory standards for neutron and gamma accuracy. 19 refs., 2 figs., 29 tabs.

  13. Subwavelength films for standoff radiation dosimetry

    Science.gov (United States)

    Alvine, Kyle J.; Bernacki, Bruce E.; Bennett, Wendy D.; Schemer-Kohrn, Alan; Suter, Jonathan D.

    2015-05-01

    We present optical subwavelength nanostructure architecture suitable for standoff radiation dosimetry with remote optical readout in the visible or infrared spectral regions. To achieve this, films of subwavelength structures are fabricated over several square inches via the creation of a 2D non-close packed (NCP) array template of radiationsensitive polymeric nanoparticles, followed by magnetron sputtering of a metallic coating to form a 2D array of separated hemispherical nanoscale metallic shells. The nanoshells are highly reflective at resonance in the visible or infrared depending on design. These structures and their behavior are based on the open ring resonator (ORR) architecture and have their analog in resonant inductive-capacitive (LC) circuits, which display a resonance wavelength that is inversely proportional to the square root of the product of the inductance and capacitance. Therefore, any modification of the nanostructure material properties due to radiation alters the inductive or capacitive behavior of the subwavelength features, which in turn changes their optical properties resulting in a shift in the optical resonance. This shift in resonance may be remotely interrogated actively using either laser illumination or passively by hyperspectral or multispectral sensing with broadband illumination. These structures may be designed to be either anisotropic or isotropic, which can also offer polarization-sensitive interrogation. We present experimental measurements of a radiation induced shift in the optical resonance of a subwavelength film after exposure to an absorbed dose of gamma radiation from 2 Mrad up to 62 Mrad demonstrating the effect. Interestingly the resonance shift is non-monotonic for this material system and possible radiation damage mechanisms to the nanoparticles are discussed.

  14. How flatbed scanners upset accurate film dosimetry.

    Science.gov (United States)

    van Battum, L J; Huizenga, H; Verdaasdonk, R M; Heukelom, S

    2016-01-21

    Film is an excellent dosimeter for verification of dose distributions due to its high spatial resolution. Irradiated film can be digitized with low-cost, transmission, flatbed scanners. However, a disadvantage is their lateral scan effect (LSE): a scanner readout change over its lateral scan axis. Although anisotropic light scattering was presented as the origin of the LSE, this paper presents an alternative cause. Hereto, LSE for two flatbed scanners (Epson 1680 Expression Pro and Epson 10000XL), and Gafchromic film (EBT, EBT2, EBT3) was investigated, focused on three effects: cross talk, optical path length and polarization. Cross talk was examined using triangular sheets of various optical densities. The optical path length effect was studied using absorptive and reflective neutral density filters with well-defined optical characteristics (OD range 0.2-2.0). Linear polarizer sheets were used to investigate light polarization on the CCD signal in absence and presence of (un)irradiated Gafchromic film. Film dose values ranged between 0.2 to 9 Gy, i.e. an optical density range between 0.25 to 1.1. Measurements were performed in the scanner's transmission mode, with red-green-blue channels. LSE was found to depend on scanner construction and film type. Its magnitude depends on dose: for 9 Gy increasing up to 14% at maximum lateral position. Cross talk was only significant in high contrast regions, up to 2% for very small fields. The optical path length effect introduced by film on the scanner causes 3% for pixels in the extreme lateral position. Light polarization due to film and the scanner's optical mirror system is the main contributor, different in magnitude for the red, green and blue channel. We concluded that any Gafchromic EBT type film scanned with a flatbed scanner will face these optical effects. Accurate dosimetry requires correction of LSE, therefore, determination of the LSE per color channel and dose delivered to the film.

  15. Standard Guide for Performance Characterization of Dosimeters and Dosimetry Systems for Use in Radiation Processing

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2009-01-01

    1.1 This guide provides guidance on determining the performance characteristics of dosimeters and dosimetry systems used in radiation processing. 1.2 This guide describes the influence quantities that might affect the performance of dosimeters and dosimetry systems and that should be considered during dosimeter/dosimetry system characterization. 1.3 Users of this guide are directed to existing standards and literature for procedures to determine the effects from individual influence quantities and from combinations of more than one influence quantity. 1.4 Guidance is provided regarding the roles of the manufacturers, suppliers, and users in the characterization of dosimeters and dosimetry systems. 1.5 This guide does not address how the dosimeter/dosimetry system characterization information is to be used in radiation processing applications or in the calibration of dosimetry systems. Note 1—For guidance on the use of dosimeter/dosimetry system characterization information for the selection and use o...

  16. Interest of numerical dosimetry in radiation protection: mean of substitution or measurements consolidation?; Interet de la dosimetrie numerique en radioprotection: moyen de substitution ou de consolidation des mesures?

    Energy Technology Data Exchange (ETDEWEB)

    Lahaye, T.; Chau, Q. [Institut de Radioprotection et de Surete Nucleaire (IRSN/DPHD/SDOS), Service Dosimetrie, 92 - Fontenay-aux-Roses (France); Ferragut, A.; Gillot, J.Y. [SAPHYMO, 91 - Massy (France)

    2003-07-01

    The use of calculation codes allows to reduce the costs and the time limits. These codes brings to operators elements to reinforce their projected dosimetry. In the cases of accidental overexposure, the numerical dosimetry comes in complement of clinical and biological investigations to give an estimation as precise as possible of the received dose. For particular situations where it does not exist an adapted instrumentation, the numerical dosimetry can substitute to conventional techniques used by regulatory dosimetry (project for aviation personnel). (N.C.)

  17. Hanford External Dosimetry Technical Basis Manual PNL-MA-842

    Energy Technology Data Exchange (ETDEWEB)

    Rathbone, Bruce A.

    2010-01-01

    The Hanford External Dosimetry Technical Basis Manual PNL-MA-842 documents the design and implementation of the external dosimetry system used at Hanford. The manual describes the dosimeter design, processing protocols, dose calculation methodology, radiation fields encountered, dosimeter response characteristics, limitations of dosimeter design under field conditions, and makes recommendations for effective use of the dosimeters in the field. The manual describes the technical basis for the dosimetry system in a manner intended to help ensure defensibility of the dose of record at Hanford and to demonstrate compliance with 10 CFR 835, DOELAP, DOE-RL, ORP, PNSO, and Hanford contractor requirements. The dosimetry system is operated by PNNL’s Hanford External Dosimetry Program (HEDP) which provides dosimetry services to all Hanford contractors. The primary users of this manual are DOE and DOE contractors at Hanford using the dosimetry services of PNNL. Development and maintenance of this manual is funded directly by DOE and DOE contractors. Its contents have been reviewed and approved by DOE and DOE contractors at Hanford through the Hanford Personnel Dosimetry Advisory Committee (HPDAC) which is chartered and chaired by DOE-RL and serves as means of coordinating dosimetry practices across contractors at Hanford. This manual was established in 1996. Since its inception, it has been revised many times and maintained by PNNL as a controlled document with controlled distribution. The first revision to be released through PNNL’s Electronic Records & Information Capture Architecture (ERICA) database was designated Revision 0. Revision numbers that are whole numbers reflect major revisions typically involving significant changes to all chapters in the document. Revision numbers that include a decimal fraction reflect minor revisions, usually restricted to selected chapters or selected pages in the document. Maintenance and distribution of controlled hard copies of the

  18. Bioverfügbarkeit verschiedener Darreichungsformen von clathriertem Dehydroepiandrosteron (DHEA) gegenüber nativem DHEA bei Frauen mit Nebennierenrindeninsuffizienz

    OpenAIRE

    Günther, Susann Margot Louise

    2006-01-01

    Bei Patientinnen mit chronischer Nebennierenrindeninsuffizienz liegt - neben dem Mangel an Glukokortikoiden und Mineralokortikoiden - ein Defizit an adrenalen Androgenen, nämlich Dehydroepiandrosteron (DHEA) und seinem Sulfatester DHEA-S vor. Obwohl DHEA und DHEA-S mengenmäßig die bedeutendsten Hormone der menschlichen Nebennierenrinde sind, gehören sie noch nicht zur standardisierten Substitutionstherapie bei Ausfall der Nebennierenrinde. In Untersuchungen der letzten Jahre konnte jedoch wie...

  19. Malignome der Prostata bei Patienten mit invasivem Harnblasenkarzinom: Onkologische Auswirkungen auf mögliche apexerhaltende Zystektomieverfahren

    Directory of Open Access Journals (Sweden)

    Gakis G

    2010-01-01

    Full Text Available Einleitung: Aktuelle Studien legen nahe, dass Zystektomien mit Erhalt des Prostataapex bei Patienten mit invasivem Harnblasenkarzinom die postoperative Kontinenz und erektile Funktion verbessern können. Jedoch existieren Bedenken hinsichtlich des postoperativen onkologischen Ergebnisses. Material und Methoden: Zwischen 2004 und 2007 wurden die klinischen und histologischen Parameter von 95 konsekutiven, radikal zystektomierten Patienten mit invasivem Harnblasenkarzinom hinsichtlich eines im Prostataapex lokalisierten Malignoms sowie der prä- und postoperativen PSA-Werte untersucht. Ergebnisse: Ein inzidentelles Prostatakarzinom (PCa wurde histologisch bei 26 von 95 Patienten (27,4 % nachgewiesen, wobei 7 hiervon im Prostataapex lokalisiert waren (mittleres Alter: 69 Jahre. Der mittlere präoperative PSA-Wert lag bei 3,3 ± 0,8 ng/ml (0,2–14 und war postoperativ unterhalb der Nachweisgrenze bei allen Patienten (mittleres Follow-up: 14,3 Monate; 3–32. Der präoperative Gesamt-PSAWert lag bei im Prostataapex lokalisierten PCa bei 5,7 ± 2,0 ng/ml (0,22–14 im Vergleich zu 2,0 ± 0,6 ng/ml (0,2–9 beim außerhalb des Prostataapex lokalisierten PCa (p 0,04. Weitere 7 der 95 (7,4 % Patienten wiesen ein Urothelkarzinom im Prostataapex ohne weitere pathologische Hinweise in der präoperativen transurethralen Resektion auf. Schlussfolgerungen: Basierend auf unseren Daten trägt ein apexerhaltendes Zystektomieverfahren bei Patienten mit invasivem Harnblasenkarzinom ein Gesamtrisiko von 14,8 % für einen Verbleib von Malignomgewebe in situ und ist deshalb nicht zu empfehlen. Weiterhin waren die PSA-Werte bei im Prostataapex lokalisierten PCa signifikant erhöht. Keiner der präoperativen Parameter konnte ein Malignom im Prostataapex sicher ausschließen.

  20. Uma pesquisa sobre o Gerenciamento de Resultados Contábeis: causas e conseqüências

    Directory of Open Access Journals (Sweden)

    Alberto Shigueru Matsumoto

    2009-10-01

    Full Text Available O gerenciamento de resultados contábeis nas empresas é um problema real, sobretudo por encontrar refúgio na flexibilidade das normas e regulamentos contábeis, que permitem alternativas distintas para a contabilização de um mesmo evento contábil. E mesmo, onde há regras, estas facultam ao gerente escolhas distintas sobre a aplicação dessas regras. Assim, o objetivo deste trabalho é identificar as principais causas e as conseqüências da prática do gerenciamento de resultados contábeis nas empresas, tendo em vista os diversos usuários, internos e externos, das demonstrações e relatórios contábeis, considerando, dentre outros, os conceitos de transparência, de subjetividade, de flexibilidade das normas contábeis e o fato de o tema ter despertado o interesse das autoridades reguladoras e da imprensa especializada. Pode-se concluir que dentre as principais causas que levam os gestores e as empresas a gerenciarem os seus resultados contábeis estão o fato de que os Princípios Contábeis Geralmente Aceitos não alcançam todas as situações possíveis e os incentivos econômico-financeiros, que as empresas e os gestores podem obter. Quanto às conseqüências, destaca-se o comprometimento das informações contidas nos demonstrativos contábeis publicados, bem como o impacto que podem ter os informes divulgados sobre as decisões dos investidores nas Bolsas de Valores.

  1. Precise Point Positioning Model Using Triple GNSS Constellations: GPS, Galileo and BeiDou

    Science.gov (United States)

    Afifi, Akram; El-Rabbany, Ahmed

    2016-12-01

    This paper introduces a comparison between dual-frequency precise point positioning (PPP) post-processing model, which combines the observations of three different GNSS constellations, namely GPS, Galileo, and BeiDou and real-time PPP model. A drawback of a single GNSS system such as GPS, however, is the availability of sufficient number of visible satellites in urban areas. Combining GNSS observations offers more visible satellites to users, which in turn is expected to enhance the satellite geometry and the overall positioning solution. However, combining several GNSS observables introduces additional biases, which require rigorous modelling, including the GNSS time offsets and hardware delays. In this paper, a GNSS post-processing PPPP model is developed using ionosphere-free linear combination. The additional biases of the GPS, Galileo, and BeiDou combination are accounted for through the introduction of a new unknown parameter, which is identified as the inter-system bias, in the PPP mathematical model. Natural Resources Canada's GPSPace PPP software is modified to enable a combined GPS / Galileo / BeiDou PPP solution and to handle the newly inter-system bias. A total of four data sets at four IGS stations are processed to verify the developed PPP model. Precise satellite orbit and clock products from the IGS-MGEX network are used to correct of the GPS, Galileo and BeiDou measurements. For the real-time PPP model the corrections of the satellites orbit and clock are obtained through the international GNSS service (IGS) real-time service (RTS). GPS and Galileo Observations are used for the GNSS RTS-IGS PPP model as the RTS-IGS satellite products are not available for BeiDou satellites. This paper provides the GNSS RTS-IGS PPP model using different satellite clock corrections namely: IGS01, IGC01, IGS01, and IGS03. All PPP models results of convergence time and positioning precision are compared to the traditional GPS-only PPP model. It is shown that combining

  2. MRA in inflammatory disorders of the central nervous system; Magnetresonanz-Angiographie bei entzuendlichen Hirnerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Felber, S. [Universitaetsklinik Innsbruck (Austria). Klinische Abt. fuer Radiologie II; Auer, A. [Universitaetsklinik Innsbruck (Austria). Inst. fuer Magnetresonanztomographie und Spektroskopie; Schmutzhard, E. [Universitaetsklinik fuer Neurologie, Innsbruck (Austria)

    2000-11-01

    In this review, we discuss the diagnostic potential of time of flight (TOF) MRA and contrast enhanced (CE) MRA in inflammatory disorders of the meninges and the brain. Cerebrovascular complications are frequently observed during infectious meningoencepalitis. 3D TOF-MRA and CE-MRA are complementary for the detection of basal intracranial artery stenosis and septic cerebral vein and sinus thrombosis due to secondary vasculitis. MRA reveals stenosis and occlusion as indirect signs of vasculitis, whereas MRI shows the inflammation of the brain and meninges and occasionally the vessel wall, together with the ischemic or hemorrhagic complication. In case of septic emboli MRA can detect peripheral occlusions and 'mycotic' aneurysms. For the diagnosis of noninfectious vasculitides of the intracranial vessels, high resolution 3D TOF-MRA is superior to CE-MRA for the detection of multiloculated segmental stenoses. However, there are presently no prospective studies on the sensitivity and specificity of MRA for these indications. Therefore, only positive MRA results can directly influence clinical management. In case of normal MRA, confirmation by catheder angiography may still be required. (orig.) [German] Diese Uebersicht behandelt die Moeglichkeiten der Time of flight MRA (TOF-MRA) und der kontrastmittelunterstuetzten MRA (KM-MRA) bei zerebral entzuendlichen Erkrankungen. Vaskulaere Komplikationen bei entzuendlichen Erkrankungen des Gehirns und der Meningen sind haeufig. Bei der infektioesen Meningitis kann die MRA eine sekundaere Vaskulitis des Circulus arteriosus Willisii und seiner Aeste, aber auch eine septische Hirnvenen- und Sinusthrombose nachweisen. Die TOF-MRA und KM-MRA liefern dabei komplementaere Informationen. In der gleichen Untersuchung kann eine entzuendliche Infiltration der Meningen bildgebend diagnostiziert werden. Bei der haematogen Herdenzephalitis im Rahmen einer Sepsis oder Endokarditis ist die MRA zur diagnose embolischer

  3. Magnetic resonance spectroscopy in schizophrenia. Possibilities and limitations; Magnetresonanzspektroskopie bei Schizophrenie. Moeglichkeiten und Grenzen

    Energy Technology Data Exchange (ETDEWEB)

    Wobrock, T. [Universitaetsklinikum des Saarlandes, Homburg/Saar (Germany). Klinik fuer Psychiatrie und Psychotherapie; Universitaetsklinikum des Saarlandes, Klinik fuer Psychiatrie und Psychotherapie, Homburg/Saar (Germany); Scherk, H.; Falkai, P. [Universitaetsklinikum des Saarlandes, Homburg/Saar (Germany). Klinik fuer Psychiatrie und Psychotherapie

    2005-02-01

    Magnetic resonance spectroscopy is a noninvasive investigative technique for in vivo detection of biochemical changes in neuropsychiatric disorders for which especially proton ({sup 1}H-MRS) and phosphorus ({sup 31}P-MRS) magnetic resonance spectroscopy have been used. In this review we explain the principles of MRS and summarize the studies in schizophrenia. A systematic literature review was carried out for {sup 1}H-MRS studies investigating schizophrenic patients compared to controls. The inconsistent results in the cited studies may be due to different study population, specific neuroimaging technique, and selected brain regions. Frequent findings are decreased PME and increased PDE concentrations ({sup 31}P-MRS) linked to altered metabolism of membrane phospholipids and decreased N-acetylaspartate (NAA) or NAA/choline ratio ({sup 1}H-MRS) linked to neuronal damage in frontal (DLPFC) or temporal regions in patients with schizophrenia. These results contribute to the disturbed frontotemporal-thalamic network assumed in schizophrenia and are supported by additional functional neuroimaging, MRI morphometry, and neuropsychological evaluation. The combination of the described investigative techniques with MRS in follow-up studies may provide more specific clues for understanding the pathogenesis and disease course in schizophrenia. (orig.) [German] Die Magnetresonanzspektroskopie (MRS) stellt ein nichtinvasives Verfahren dar, mit dem in vivo biochemische Veraenderungen spezifischer Hirnregionen bei verschiedenen psychiatrischen Erkrankungen untersucht werden koennen. Dabei werden insbesondere die Protonenmagnetresonanzspektroskopie ({sup 1}H-MRS) sowie die Phosphormagnetresonanzspektroskopie ({sup 31}P-MRS) verwendet. In der vorliegenden Uebersichtsarbeit werden die methodischen Grundlagen erlaeutert sowie die Befundlage bei der Schizophrenie referiert. Fuer die Darstellung der Studien zur {sup 1}H-MRS bei schizophrenen Patienten im Vergleich zu einer Kontrollgruppe

  4. Anwendung der extrakorporalen Stoßwellentherapie bei kalzifizierender Periathropathia humeroscapularis, Fersensporn und Epicondylitis humeri - Erfahrungsbericht aus dem Wilhelminenspital

    Directory of Open Access Journals (Sweden)

    Feyertag J

    2004-01-01

    Full Text Available Die Stoßwellentherapie wird bei verschiedenen Indikationen, die unter konservativen Therapien schwer zu schwer zu behandeln sind, eingesetzt. Dazu zählen die kalzifizierenden Schultererkrankungen (Tendinitis calcarea, Epicondylitis humeri (EHR und die plantare Fasciitis mit/ohne plantarem Fersensporn (FSP. Berichtet werden die Ergebnisse von 147 Patienten (102 Frauen/45 Männer, mittleres Alter betrug 57,8 Jahre, die mittels einer einmaligen extrakorporalen Stoßwellentherapie (ESWT (Tend. calc. 82 %, FSP 11 % oder EHR 7 % mittels eines HMT-ReflecTron therapiert wurden. Verabreicht wurden im Mittel 1.800 Stoßwellen. Untersucht wurde die subjektive Verbesserung der Schmerzen anhand einer visuellen Analogskala vor und 6 Wochen nach der Therapie bei allen Patienten. Bei Patienten mit Tendinitis calcarea wurde auch eine Verbesserung der Funktion sowie Veränderungen der Kalzifizierungen untersucht. Bei allen Patienten konnte eine statistisch signifikante Verbesserung der Schmerzen sowie des Bewegungsumfanges beobachtet werden (p 0,0001. Röntgenaufnahmen ergaben eine partielle Verkleinerung der Kalkdepots bei ca. 80 % der Patienten. Aufgrund der geringen Zahl der Patienten fand sich für die EHR keine signifikante Verbesserung der Schmerzsymptomatik. Eine einmalige ESWT kann zu einer deutlichen Verbesserung der Schmerzsymptomatik und zu einer Verbesserung des Bewegungsumfanges führen. Bei 80 % der Patienten mit einer Tendinitis calcarea findet sich weiter eine partielle Verkleinerung der Kalkdepots 6 Wochen nach Therapie.

  5. Antikoagulantientherapie bei venösen Thromboembolien in Abhängigkeit von der Grunderkrankung des Patienten

    Directory of Open Access Journals (Sweden)

    Seinost G

    2009-01-01

    Full Text Available Die therapeutische Basismaßnahme bei Patienten mit venösen Thromboembolien ist die Antikoagulation – initial in erster Linie mit einem niedermolekularen Heparin in therapeutischer Dosierung, weiterführend mit oraler Antikoagulation. Bei Tumorpatienten ist eine Verlängerung der Antikoagulation mit einem niedermolekularen Heparin für die ersten 3–6 Monate indiziert, danach sollte die weitere Antikoagulation individuell entschieden werden. Bei Patienten mit zerebraler oder peripherer AVK oder KHK, die eine venöse Thromboembolie erleiden, ist es zulässig, die Thrombozytenfunktionshemmung für die Dauer der Antikoagulation zu pausieren. Die Antikoagulation von Patienten mit chronischer Niereninsuffizienz kann ebenfalls mit niedermolekularem Heparin erfolgen. Bei Patienten mir höhergradiger Einschränkung der Kreatininclearance sollte jedoch eine entsprechende Reduktion der therapeutischen Dosis des niedermolekularen Heparins – idealerweise optimiert durch eine Kontrolle des Anti-Xa-Spiegels – oder die Antikoagulation mit unfraktioniertem Heparin durchgeführt werden. Patienten mit Antiphospholipid-Antikörper und venöser Thromboembolie werden in der Regel mit oraler Antikoagulation bei einer INR von 2–3 behandelt. Nur bei einem thromboembolischen Rezidivereignis unter suffizienter Antikoagulation ist eine Intensivierung bzw. Erweiterung des antithrombotischen Managements sinnvoll.

  6. Sensitivity Enhancement of Bead-based Electrochemical Impedance Spectroscopy (BEIS) biosensor by electric field-focusing in microwells.

    Science.gov (United States)

    Shin, Kyeong-Sik; Ji, Jae Hoon; Hwang, Kyo Seon; Jun, Seong Chan; Kang, Ji Yoon

    2016-11-15

    This paper reports a novel electrochemical impedance spectroscopy (EIS) biosensors that uses magnetic beads trapped in a microwell array to improve the sensitivity of conventional bead-based EIS (BEIS) biosensors. Unloading the previously measured beads by removing the magnetic bar enables the BEIS sensor to be used repeatedly by reloading it with new beads. Despite its recyclability, the sensitivity of conventional BEIS biosensors is so low that it has not attracted much attentions from the biosensor industry. We significantly improved the sensitivity of the BEIS system by introducing of a microwell array that contains two electrodes (a working electrode and a counter electrode) to concentrate the electric field on the surfaces of the beads. We confirmed that the performance of the BEIS sensor in a microwell array using an immunoassay of prostate specific antigen (PSA) in PBS buffer and human plasma. The experimental results showed that a low concentration of PSA (a few tens or hundreds of fg/mL) were detectable as a ratio of the changes in the impedance of the PBS buffer or in human plasma. Therefore, our BEIS sensor with a microwell array could be a promising platform for low cost, high-performance biosensors for applications that require high sensitivity and recyclability.

  7. In vivo dosimetry: trends and prospects for brachytherapy

    DEFF Research Database (Denmark)

    Kertzscher, Gustavo; Rosenfeld, A.; Beddar, S.

    2014-01-01

    The error types during brachytherapy (BT) treatments and their occurrence rates are not well known. The limited knowledge is partly attributed to the lack of independent verification systems of the treatment progression in the clinical workflow routine. Within the field of in vivo dosimetry (IVD)...

  8. Radiation dosimetry onboard the International Space Station ISS.

    Science.gov (United States)

    Berger, Thomas

    2008-01-01

    Besides the effects of the microgravity environment, and the psychological and psychosocial problems encountered in confined spaces, radiation is the main health detriment for long duration human space missions. The radiation environment encountered in space differs in nature from that on earth, consisting mostly of high energetic ions from protons up to iron, resulting in radiation levels far exceeding the ones encountered on earth for occupational radiation workers. Therefore the determination and the control of the radiation load on astronauts is a moral obligation of the space faring nations. The requirements for radiation detectors in space are very different to that on earth. Limitations in mass, power consumption and the complex nature of the space radiation environment define and limit the overall construction of radiation detectors. Radiation dosimetry onboard the International Space Station (ISS) is onboard the International Space Station (ISS) is accomplished to one part as "operational" dosimetry accomplished to one part as "operational" dosimetry aiming for area monitoring of the radiation environment as well as astronaut surveillance. Another part focuses on "scientific" dosimetry aiming for a better understanding of the radiation environment and its constitutes. Various research activities for a more detailed quantification of the radiation environment as well as its distribution in and outside the space station have been accomplished in the last years onboard the ISS. The paper will focus on the current radiation detectors onboard the ISS, their results, as well as on future planned activities.

  9. In vivo dosimetry with silicon diodes in total body irradiation

    Science.gov (United States)

    Oliveira, F. F.; Amaral, L. L.; Costa, A. M.; Netto, T. G.

    2014-02-01

    The aim of this work is the characterization and application of silicon diode detectors for in vivo dosimetry in total body irradiation (TBI) treatments. It was evaluated the diode response with temperature, dose rate, gantry angulations and field size. A maximum response variation of 2.2% was obtained for temperature dependence. The response variation for dose rate and angular was within 1.2%. For field size dependence, the detector response increased with field until reach a saturation region, where no more primary radiation beam contributes for dose. The calibration was performed in a TBI setup. Different lateral thicknesses from one patient were simulated and then the calibration factors were determined by means of maximum depth dose readings. Subsequent to calibration, in vivo dosimetry measurements were performed. The response difference between diode readings and the prescribed dose for all treatments was below 4%. This difference is in agreement as recommended by the International Commission on Radiation Units and Measurements (ICRU), which is ±5%. The present work to test the applicability of a silicon diode dosimetry system for performing in vivo dose measurements in TBI techniques presented good results. These measurements demonstrated the value of diode dosimetry as a treatment verification method and its applicability as a part of a quality assurance program in TBI treatments.

  10. Fiber-coupled Luminescence Dosimetry in Therapeutic and Diagnostic Radiology

    DEFF Research Database (Denmark)

    Andersen, Claus Erik

    2011-01-01

    Fiber-coupled luminescence dosimetry is an emerging technology with several potentially attractive features of relevance for uses in therapeutic and diagnostic radiology: direct water equivalence (i.e. no significant perturbation of the radiation field in a water phantom or a patient), sub...

  11. Retrospective dosimetry using unheated quartz: A feasibility study

    DEFF Research Database (Denmark)

    Thomsen, Kristina Jørkov; Bøtter-Jensen, L.; Murray, A.S.

    2002-01-01

    Most attempts to apply retrospective dosimetry to building materials have made use of heated (sensitised) items such as brick or tile ceramic. Unfired materials, such as concrete, are far more widespread in the industrial environment, but unfortunately these cannot be assumed to contain a negligi...

  12. Dosimetry studies on prototype 241Am sources for brachytherapy.

    Science.gov (United States)

    Nath, R; Gray, L

    1987-06-01

    Sealed sources of 241Am emit primarily 60 keV photons which, because of multiple Compton scattering, produce dose distributions in water that are comparable to those from 226Ra or 137Cs. However, americium gamma rays can be shielded by thin layers of high atomic number materials since the half value layer thickness is only 1/8th of a mm of lead for americium gamma rays as compared to a value of 12 mm for 226Ra gamma rays. This may allow effective in vivo shielding of critical organs, for example; the bladder can be partially shielded by hypaque solution, and the rectum and sigmoid colon by barium sulfate. In addition, the exposure to medical personnel involved in intracavitary application and patient care may be reduced substantially by the use of relatively thin lead aprons and light weight, portable shields. To investigate the feasibility of 241Am sources for intracavitary irradiation, dosimetry studies on prototype 241Am sources have been performed and a computer model for the determination of dose distributions around encapsulated cylindrical sources of 241Am has been developed and tested. Results of dosimetry measurements using ionization chambers, lithium fluoride thermoluminescent dosimeters, a scanning scintillation probe, and film dosimetry, confirm theoretical predictions that these sources can deliver dose rates adequate for intracavitary irradiation. Further dosimetry measurements in simulated clinical situations using lead foils and test tubes filled with hypaque or barium sulfate, confirm the predicted effectiveness of in vivo shielding which can be readily achieved with 241Am sources.

  13. Carbon beam dosimetry using VIP polymer gel and MRI

    DEFF Research Database (Denmark)

    Kantemiris, I; Petrokokkinos, L; Angelopoulos, A

    2009-01-01

    VIP polymer gel dosimeter was used for Carbon ion beam dosimetry using a 150 MeV/n beam with 10 Gy plateau dose and a SOBP irradiation scheme with 5 Gy Bragg peak dose. The results show a decrease by 8 mm in the expected from Monte Carlo simulation range in water, suggesting that the dosimeter...

  14. Advances in kilovoltage x-ray beam dosimetry

    Science.gov (United States)

    Hill, Robin; Healy, Brendan; Holloway, Lois; Kuncic, Zdenka; Thwaites, David; Baldock, Clive

    2014-03-01

    This topical review provides an up-to-date overview of the theoretical and practical aspects of therapeutic kilovoltage x-ray beam dosimetry. Kilovoltage x-ray beams have the property that the maximum dose occurs very close to the surface and thus, they are predominantly used in the treatment of skin cancers but also have applications for the treatment of other cancers. In addition, kilovoltage x-ray beams are used in intra operative units, within animal irradiators and in on-board imagers on linear accelerators and kilovoltage dosimetry is important in these applications as well. This review covers both reference and relative dosimetry of kilovoltage x-ray beams and provides recommendations for clinical measurements based on the literature to date. In particular, practical aspects for the selection of dosimeter and phantom material are reviewed to provide suitable advice for medical physicists. An overview is also presented of dosimeters other than ionization chambers which can be used for both relative and in vivo dosimetry. Finally, issues related to the treatment planning and the use of Monte Carlo codes for solving radiation transport problems in kilovoltage x-ray beams are presented.

  15. Eurados trial performance test for neutron personal dosimetry

    DEFF Research Database (Denmark)

    Bordy, J.M.; Stadtmann, H.; Ambrosi, P.;

    2001-01-01

    measured, but particular problems were noted in the determination of intermediate energy fields and large incident angles, demonstrating the difficulties of neutron personal dosimetry. Of particular concern from a radiological protection point of view was the large number of results underestimating...... personal dose equivalent. A considerable over-response was noted in a few cases....

  16. Application of spherical micro diodes for brachytherapy dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Broisman, Andrey, E-mail: andreybr@ariel.ac.i [Medical Physics, Ariel University Center, Ariel 40700 (Israel); Shani, Gad [Biomedical Engineering, Ben Gurion University, P.O. Box 653, Beer Sheva 84105 (Israel)

    2011-03-15

    The research presented in this paper demonstrates the feasibility and the advantages of using spherical micro diodes for radiation dosimetry. The spherical symmetry of the diode response is demonstrated, compared to that of planar diodes. The application of the spherical diode described here is for radiotherapy dosimetry, particularly brachytherapy. Measurements were done in PMMA phantoms. The advantage of the spherical diode is that it can be used for radiation measurement in a 4{pi} geometry, it was demonstrated by measurements in both axial and azimuthal planes. The diodes were found to respond equally to radiation coming from all directions, directly from the source or due to scattered radiation within the medium. In the present work 1.8 mm diameter silicone diodes were used. The small size of these spherical diodes provides local dose measurement and can be used for in situ dosimetry while treatment takes place. Treatment planning correction can be made accordingly. Commercially available seeds of the isotopes I{sup 125} and Pd{sup 103} were used as radiation sources. The spherical diodes response was compared with that of planar diodes XRB generally used for UV and X-ray dosimetry, and with TLD measurements. We have also compared the measured results with Monte Carlo simulation, applying the MCNP code and with calculations shown in the TG-43 report.

  17. Optically stimulated luminescence dosimetry using natural and synthetic materials

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; McKeever, S.W.S.

    1996-01-01

    The application of optically stimulated luminescence (OSL) for use in radiation dosimetry is reviewed. A broad description is given of OSL techniques developed at Riso National Laboratory and at Oklahoma State University, and recent collaborative investigations on the properties of a variety...

  18. Graphite mixed magnesium borate TL dosemeters for beta ray dosimetry

    DEFF Research Database (Denmark)

    Prokic, M; Christensen, Poul

    1984-01-01

    Sintered MgB4O7:Dy dosemeters with graphite contents from 1 to 10% were investigated for application for personnel dosimetry. Data are given on dose response, dose threshold, reproducibility, beta energy response and fading. Furthermore, results from practical field experiments are presented...

  19. Fast 2D phantom dosimetry for scanning proton beams

    NARCIS (Netherlands)

    Boon, SN; van Luijk, P; Schippers, JM; Meertens, H; Denis, JM; Vynckier, S; Medin, J; Grusell, E

    1998-01-01

    A quality control system especially designed for dosimetry in scanning proton beams has been designed and tested. The system consists of a scintillating screen (Gd2O2S:Tb), mounted at the beam-exit side of a phantom, and observed by a low noise CCD camera with a long integration time. The purpose of

  20. Preclinical animal research on therapy dosimetry with dual isotopes

    NARCIS (Netherlands)

    M.W. Konijnenberg (Mark); M. de Jong (Marion)

    2011-01-01

    textabstractPreclinical research into radionuclide therapies based on radiation dosimetry will enable the use of any LET-equivalent radionuclide. Radiation dose and dose rate have significant influence on dose effects in the tumour depending on its radiation sensitivity, possibilities for repair of

  1. Workshop on dosimetry for radon and radon daughters

    Energy Technology Data Exchange (ETDEWEB)

    Turner, J.E.; Holoway, C.F.; Loebl, A.S. (eds.)

    1978-05-01

    Emphasis is placed on the dosimetry for radon and daughters, rather than on monitoring and instrumentation. The objectives of the meeting were to exchange scientific information, to identify problem areas in radon-daughter dosimetry, and to make any observations or recommendations by the participants through issuance of this report. The discussion topics included the history of dosimetry for radon and daughters, human data, aerosols, deposition and movement in the respiratory tract, dose calculations, dose-to-working-level-month (WLM) conversion factors, animal experiments, and the development of regulations and remedial criteria for reducing population exposures to radon daughters. This report contains a summary of Workshop discussions plus individual statements contributed by several of the participants. The outstanding problem areas from the standpoint of dosimetry appear to involve the appropriate lung organ mass to be used (average lung-tissue dose vs. high-level local dose); recognition of the discrete, rather than continuous, structure of the mucus; lack of knowledge about lung clearance; the variability of dose with the degree of disequilibrium and the unattached fraction of radon daughters for a given WLM; and questions about the character of uranium mine atmospheres actually breathed in the older mines from which much of the epidemiological information originates. The development of criteria for taking remedial action to reduce exposures involves additional concerns of basing long-term risk assessment on short-term sampling and applying WLM data for miners to general populations.

  2. Optically stimulated luminescence dosimetry using natural and synthetic materials

    DEFF Research Database (Denmark)

    Bøtter-Jensen, L.; McKeever, S.W.S.

    1996-01-01

    The application of optically stimulated luminescence (OSL) for use in radiation dosimetry is reviewed. A broad description is given of OSL techniques developed at Riso National Laboratory and at Oklahoma State University, and recent collaborative investigations on the properties of a variety of n......, and unseparated materials such as bricks and porcelain items....

  3. Quality control for X-ray dosimetry with Fricke dosimeter

    Energy Technology Data Exchange (ETDEWEB)

    Souza, Vivianne Lucia Bormann de [Centro Regional de Cincias Nucleares (CRCN-NE/CNEN-PE), Recife, PE (Brazil)]. E-mail: lsouza@cnen.gov.br; Austerlitz, C. [East Carolina University, NC (United States)]. E-mail: camposc@ecu.edu

    2007-07-01

    It is a well-established fact that the success of radiation therapy is dependent on the accurate dosimetry of the radiation beam used. This dosimetry must include equipment performance as well. A system for Fricke dosimetry was used for this purpose. The Fricke solution and a parallel ionization chamber (used for comparison) were irradiated with an X-ray beam from a Pantak X-ray equipment. The ionization chamber was positioned at a distance of 500 mm of the focal point, in the central axis of the X-ray field which is defined as 100x100 mm{sup 2} at the calibration distance. A plexiglas phantom appropriate to hold the polypropylene tube was used to irradiate the vials with the Fricke solution. The irradiated solutions were transferred directly from the polypropylene vials to 10 mm length cuvettes and the optical densities were measured in 304 nm using a Beckman Counter Model DU 640 spectrophotometer. Three institutions were visited to verify their procedures and two were in accordance with the lAEA recommended procedures for soft X-ray dosimetry. The results of the measurements performed in the institutions visited show that the Fricke dosimeter system developed can be used for quality control for soft X-ray equipment. (author)

  4. Chemical dosimetry techniques for various applications under different geometries

    CERN Document Server

    Gupta, B L; Narayan, G R; Nilekani, S R

    2000-01-01

    This paper gives the results of dosimetry for various applications under different geometrical arrangements. These applications include: gamma chambers, blood irradiators, radiotherapy using both sup 6 sup 0 Co and accelerators, animal irradiations with different types of radiation sources, fluid irradiators for sludge and rubber latex and industrial electron irradiators. The dosimeters used were Fricke, FBX and alanine/glutamine (spectrophotometric readout).

  5. Precision dosimetry system suited for low temperature radiation damage experiments

    DEFF Research Database (Denmark)

    Andersen, H.H.; Hanke, C.C.; Sørensen, H.

    1967-01-01

    A calorimetric system for dosimetry on a beam of charged particles is described. The calorimeter works at liquid helium temperature. The total dose may be measured with an accuracy of 0.3%, and the dose per area with 0.4%. No theoretical corrections are needed. © 1967 The American Institute...

  6. Preclinical animal research on therapy dosimetry with dual isotopes

    NARCIS (Netherlands)

    M.W. Konijnenberg (Mark); M. de Jong (Marion)

    2011-01-01

    textabstractPreclinical research into radionuclide therapies based on radiation dosimetry will enable the use of any LET-equivalent radionuclide. Radiation dose and dose rate have significant influence on dose effects in the tumour depending on its radiation sensitivity, possibilities for repair of

  7. The Design of Compass/BeiDou Navigation Satellite Terminal for Migrant Bird Research

    Directory of Open Access Journals (Sweden)

    Yaohui Li

    2014-01-01

    Full Text Available A terminal of Compass Navigation Satellite System (CNSS, which can not only support BeiDou-1 and BeiDou-2 but also support Global Positioning System (GPS, is designed to research the activities of the migrant birds, with our novel design of a multiband antenna. By a high-density integration, this terminal is designed with a compact size and light weight. When the terminal is assembled to a whooper swan, its flying trace is recorded by the CNSS, which is in agreement with that of GPS. The flying route map based on the CNSS is useful to check the situation and habit of the migrant bird, which is important for animal protection and bird flu outbreak prediction.

  8. Auswirkungen des Urin-pH auf das Ballonvolumen bei Dauerkathetern

    Directory of Open Access Journals (Sweden)

    Pannek J

    2007-01-01

    Full Text Available Einleitung: Eine häufige Komplikation der transurethralen oder suprapubischen Dauerkatheterversorgung ist die Dislokation durch eine insuffiziente Katheterblockung. Die Auswirkungen des Urin-pH auf das Ballonvolumen sind dabei bisher nicht untersucht. Methodik: In einer In-vitro-Studie wurden Dauerkatheter aus Silikon und Latex mit entweder 10%iger Glyzerinlösung oder mit 0,9%iger NaCl-Lösung geblockt und 14 Tage bei verschiedenen pH-Werten in künstlichem Urin gelagert. Nach diesem Zeitraum wurde die rückgewonnene Flüssigkeit aus dem Katheterballon gemessen. Ergebnisse: Bei allen Katheterballons wurde eine Reduktion des Ballonvolumens von maximal 20 % festgestellt. Weder das verwendete Füllmedium noch das Kathetermaterial hatte signifikante Auswirkungen auf das Ausmaß der Volumenänderung. Schlußfolgerung: Die Änderung des Urin-pH führt nicht zu Volumenverschiebungen im Katheterballon.

  9. The personal dosimetry in Mexico; La dosimetria personal en Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Salazar, M.A. [Proxtronics/ Asesoria Integral en Dosimetria Termoluminiscente S.A. de C.V., Canal de Miramontes 2030-14, Col. Educacion, 04400 Mexico D.F. (Mexico)]. e-mail: aidtsa@avantel.net

    2006-07-01

    The Personal Dosimetry in Mexico, has an approximately 30 year-old history; and it had been and it is at the moment, one of the more important resources with which the personnel that works with ionizing radiation sources counts for its protection. The Personal Dosimetry begins with the film dosimetry, technique that even continues being used at the present time by some users, and the main reason of its use is for economic reasons. At the moment this technique, it has been surpassed, by the Thermoluminescent dosimetry, which has taken a lot of peak, mainly by the technological development with which it is counted at the present time; what has given as a result that this technique becomes tip technology; that supported in the characteristic of the used materials, as the handling and processing of the information associated with the new PC, digitizer cards, software etc, what has allowed increases it potential. In this work the current necessities of the market are presented as well as an analysis of the future real necessities in Mexico, at national level, the companies that provide this service and that they spread to satisfy this necessity of the market, including the different used technologies are also mentioned. The application ranges, at the same time, of the advantages and disadvantages of the different systems of Personal Dosimetry in the market. The companies that at the moment provide the service of Personal Dosimetry, its use materials and equipment in indistinct form, for the monitoring of gamma radiation, beta particles, different qualities of x-ray radiation, and sometimes neutrons. The monitoring of the exposed personnel at the diverse sources of ionizing radiation mentioned is carried out in many occasions without having with the materials (detectors), neither the appropriate infrastructure and therefore without the quality control that guarantees a correct evaluation of the dose equivalent, as a result of the exposure to the ionizing radiations; it

  10. Development of probabilistic internal dosimetry computer code

    Science.gov (United States)

    Noh, Siwan; Kwon, Tae-Eun; Lee, Jai-Ki

    2017-02-01

    Internal radiation dose assessment involves biokinetic models, the corresponding parameters, measured data, and many assumptions. Every component considered in the internal dose assessment has its own uncertainty, which is propagated in the intake activity and internal dose estimates. For research or scientific purposes, and for retrospective dose reconstruction for accident scenarios occurring in workplaces having a large quantity of unsealed radionuclides, such as nuclear power plants, nuclear fuel cycle facilities, and facilities in which nuclear medicine is practiced, a quantitative uncertainty assessment of the internal dose is often required. However, no calculation tools or computer codes that incorporate all the relevant processes and their corresponding uncertainties, i.e., from the measured data to the committed dose, are available. Thus, the objective of the present study is to develop an integrated probabilistic internal-dose-assessment computer code. First, the uncertainty components in internal dosimetry are identified, and quantitative uncertainty data are collected. Then, an uncertainty database is established for each component. In order to propagate these uncertainties in an internal dose assessment, a probabilistic internal-dose-assessment system that employs the Bayesian and Monte Carlo methods. Based on the developed system, we developed a probabilistic internal-dose-assessment code by using MATLAB so as to estimate the dose distributions from the measured data with uncertainty. Using the developed code, we calculated the internal dose distribution and statistical values ( e.g. the 2.5th, 5th, median, 95th, and 97.5th percentiles) for three sample scenarios. On the basis of the distributions, we performed a sensitivity analysis to determine the influence of each component on the resulting dose in order to identify the major component of the uncertainty in a bioassay. The results of this study can be applied to various situations. In cases of

  11. SEVENTH DOE WORKSHOP ON PERSONNEL NEUTRON DOSIMETRY

    Energy Technology Data Exchange (ETDEWEB)

    Vallario, E J

    1978-10-24

    This workshop was the seventh of a series and was held on October 23-24. 1978, at the Central Electricity Generating Board, HQ, London, England. Typically~ attendees at the Workshop were concerned with one of three activities: studying and refining existing techniques in an attempt to quantify already-known parameters with greater precision, looking for ways to apply existing neutron dosirr:etry techniques to a specific local problem, identifying the needs and weaknesses of existing systems, with the goal of improving and passibly simplifying field measurements. The types of neutron dosimetry techniques discussed by participants included albedo dosimeters, track etch, and TLD. One speaker reported on NTA film, noting that fading could be eliminated by drying the emulsion in dry nitrogen before field use. There were no reports on tissue equivalent proportional counters or activation analysis. One participant discussed a metal oxide silicon dosimeter. The need to develop a consistent standard terminology, as well as calibration sources and techniques, on both the national and international level was evident. The need for standardization is particularly acute in the U.S. Techniques for evaluating dosimeter response in the field should he standardized, since several different instruments with widely different response characteristics are currently being used. The choice of instruments is often parochial. Also. the type and use of phantoms should be standardized. Neutron dose assignment is significantly affected by the position of the dosimeter on the body. for example, a typical albedo dosimeter may give differences of up to 20% depending on whether it is worn on the belt or chest. Larger errors are encountered with front-to-back (angular} orientation. 1n an attempt to minimize such errors~ at least two European facilities are using neutron dosimeter belts, which provide dosimeters both in front and in back of the wearer. The gamma-to-neutron ratio around nuclear power

  12. Functional MR urography in patients with renal transplants; Funktionelle MR-Urographie bei Patienten mit Nierentransplantaten

    Energy Technology Data Exchange (ETDEWEB)

    Knopp, M.V. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Doersam, J. [Heidelberg Univ. (Germany). Abt. Urologie und Poliklinik; Oesingmann, N. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Piesche, S. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Hawighorst, H. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Wiesel, M. [Heidelberg Univ. (Germany). Abt. Urologie und Poliklinik; Schad, L.R. [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie; Kaick, G. van [Deutsches Krebsforschungszentrum, Heidelberg (Germany). Forschungsschwerpunkt Radiologische Diagnostik und Therapie

    1997-03-01

    Purpose: To assess the value of functional magnetic resonance urography for the noninvasive postoperative evaluation of renal transplants. Methods: A saturation inversion projection sequence allows the selective imaging of strongly T1 weighted signal from the MR contrast agent. A coronal slab leads to images comparable to conventional urography which can be acquired as a sequence with four images per minute. Results: 15 patients with urologic questionable findings after renal transplantation were studied. FMRU revealed in 6 patients normal findings, in 6 moderate dilatation of the renal pelvis without any urodynamic relevant obstruction. 3 pathologic findings, ureteral leak, ureteropelvic-junction obstruction and ureteral stenosis were diagnosed and consequently surgically treated. The imaging quality in all studies was diagnostic and urologically relevant. Conclusion: FMRU can be used as a noninvasive technique for the assessment of renal transplant in cases with suspicion of complication in the excretory system. (orig.) [Deutsch] Fragestellung: Laesst sich die funktionelle Magnetresonanzurographie (FMRU) zur nichtinvasiven Diagnostik im postoperativen Verlauf von Nierentransplantaten einsetzen? Methodik: Mit Hilfe einer Saturation-Inversion-Projektionstechnik kann eine selektive Darstellung der durch das Kontrastmittel stark verkuerzten T1-gewichteten Signalanteile erreicht werden. Durch koronare Schichtfuehrung entstehen Bilder vergleichbar mit einer konventionellen Urographie, die als Sequenz von 4 Bildern pro Minute aufgenommen werden. Ergebnisse: 15 Patienten mit urologisch abklaerungsbeduerftigen Befunden nach Nierentransplantation wurden untersucht. Mit der FMRU konnte bei 6 Patienten ein unauffaelliger Befund, bei 6 eine diskrete Dilatation des Nierenbeckenkelchsystems ohne urodynamisch relevante Abflussbehinderung nachgewiesen werden, jeweils eine Harnleiterleckage, eine Harnleitermuendungsstenose und eine Harnleiterabgangsenge wurden diagnostiziert und

  13. Diagnostic value of SPECT in bone scintigraphy; Bedeutung der SPECT bei der Knochenszintigraphie

    Energy Technology Data Exchange (ETDEWEB)

    Gratz, S.; Becker, W. [Goettingen Univ. (Germany). Abt. fuer Nuklearmedizin

    2000-05-01

    Single Photon Emission Computed Tomography (SPECT) reflects the realization of its ability to remove unwanted activity from bone structures with greater contrast. Especially in the spine SPECT improves the diagnostic accuracy compared with planar bone scintigraphy, because smaller structures of single vertebral bodies can be diagnosed with better anatomic resolution due to SPECT with consequently higher sensitivities and specificities. With SPECT, alterations of the lateral part of the vertebral body, pars interacticularis and smaller facet joints can be correctly diagnosed as spondylarthrotic degenerative alterations. In patients with suspected spine malignancies SPECT did not demonstrate to be a reliable instrument for diagnosing malignancy. We recommend to perform SPECT in case of patients with back pain and suspected spine pathologies seen on planar bone scans, since a correct diagnosis of especially benign spondylarthrotic spine lesions is possible with SPECT. With SPECT, a reduction of radiological examinations of 23% should be possible. (orig.) [German] Die Single-Photonenemissionscomputertomographie (SPECT) erlaubt bei der Knochenszintigraphie eine ueberlagerungsfreie Darstellung von Knochenstrukturen mit hoher Kontrastgenauigkeit. Insbesondere bei Wirbelsaeulenerkrankungen ermoeglicht SPECT einen deutlichen diagnostischen Zugewinn gegenueber planaren Aufnahmen, da kleinere Strukturen einzelner Wirbelkoerper aufgrund des hohen anatomischen Aufloesungsvermoegens mit SPECT sehr sensitiv und spezifisch dargestellt werden. Veraenderungen, die sich auf den lateralen Anteil des Wirbelkoerpers, die Pars interarticularis und die kleinen Facettengelenke projizieren, koennen mit SPECT als spondylarthrotisch degenerative Laesionen eingestuft werden. Zwingende SPECT-szintigraphische Kriterien, die eine Laesion als eindeutig maligne nachweisen, gibt es dagegen nicht. Wir denken, dass SPECT bei allen Patienten mit Rueckenschmerzen und planarszintigraphisch suspekten

  14. Untersuchungen zum dynamischen Verhalten von topologisch optimierten Pressverbänden bei Umlaufbiegung

    OpenAIRE

    Heydt, Jürgen Friedrich

    2012-01-01

    Die Lebensdauer von Pressverbindungen wird infolge der Reibdauerbeanspruchung begrenzt. Die Reibdauerbeanspruchung entsteht aufgrund einer dynamischen Beanspruchung, die zu einer oszillierenden Gleitbewegung unter Einfluss des Fugendrucks zwischen Welle und Nabe führt. Eine Gleitbewegung zwischen Welle und Nabe, auch Schlupf genannt, ist bei einer zweckmäßigen Beanspruchung der Pressverbände unvermeidbar. In dieser Arbeit konnten drei grundsätzliche Aspekte für die Auslegung von Querpress...

  15. HRCT of the lung in collagen vascular diseases; HRCT der Lunge bei Kollagenosen

    Energy Technology Data Exchange (ETDEWEB)

    Diederich, S. [Inst. fuer Klinische Radiologie, Westfaelische Wilhelms-Univ., Muenster (Germany); Roos, N. [Inst. fuer Klinische Radiologie, Westfaelische Wilhelms-Univ., Muenster (Germany); Schmitz-Linneweber, B. [Medizinische Klinik B, Westfaelische Wilhelms-Univ., Muenster (Germany); Gaubitz, M. [Medizinische Klinik B, Westfaelische Wilhelms-Univ., Muenster (Germany); Peters, P.E. [Inst. fuer Klinische Radiologie, Westfaelische Wilhelms-Univ., Muenster (Germany)

    1996-07-01

    bei progressiver Systemsklerose (PSS, Sklerodermie), systemischem Lupus erythematodes (SLE), `mixed connective tissue disease` (MCTD, Sharp-Syndrom), Sjoegren-Syndrom, Mischkollagenose (`Overlap`syndrom) und rheumatoider Arthritis (RA) werden dargestellt. Ausserdem werden fuer die einzelnen Krankheitsbilder jeweils spezifische Phaenomene erlaeutert wie die Oesophagusbeteiligung bei PSS, akute Pneumonitis oder pulmonale Haemorrhagie bei SLE, lymphoproliferative Erkrankungen beim Sjoegren-Syndrom und nekrobiotische Rundherde bei RA. (orig.)

  16. Früherkennung und Frühintervention bei Psychosen

    Directory of Open Access Journals (Sweden)

    Mossaheb N

    2011-01-01

    Full Text Available In den vergangenen 20 Jahren wurden vermehrt Möglichkeiten der Frühintervention bei psychotischen Störungen erforscht. Ausgangspunkt war einerseits die seit Langem bekannte Beobachtung eines Prodromalstadiums der Erkrankung. Andererseits trug die Erkenntnis um die negativen Effekte einer langen Dauer unbehandelter psychotischer Symptome dazu bei, präventive Maßnahmen zu entwickeln. Maßgeblich für die adäquate Früherkennung war letztlich die Entwicklung operationalisierter Kriterien spezifischer Risikosyndrome: die „Ultrahigh- risk“-Kriterien eines „at-risk mental state“. In Anbetracht dessen wird derzeit ein klinisches Stadienmodell zur stadiengerechten Behandlung der Erkrankung diskutiert. Die Ergebnisse neurobiologischer Studien weisen ebenfalls auf einen stadienhaften Verlauf bereits im Vorfeld der klinischen Manifestation psychotischer Störungen hin. Mittels indizierter Prävention können Menschen mit „at-risk mental state“ einer frühzeitigen Intervention zugeführt werden. Die ersten präventiven Frühinterventionsstudien bei Personen mit erhöhtem Risiko beinhalten die Adaptierung von Therapiekonzepten, die bei manifesten Psychosen wirksam sind, u. a. mit Antipsychotika und kognitiver Verhaltenstherapie. Diese Studien waren während der Behandlung, aber nicht darüber hinaus wirksam. In weiterer Folge wurden auch auf neueren Konzepten basierende – wie der Neuroprotektion – Interventionen untersucht. Eine placebokontrollierte Studie, an der 81 Personen teilnahmen, konnte vor Kurzem eine nachhaltige Wirksamkeit von Omega-3- Fettsäuren (Fischöl zur Reduktion des Psychoserisikos zeigen. Eine 3-monatige Intervention senkte dabei über den Zeitraum eines Jahres die Psychoserate um 23 %. Eine Replikation dieses Ergebnisses wird derzeit in 8 Zentren weltweit durchgeführt.

  17. Untersuchungen zur Bedeutung anthelminthischer Behandlungen bei der Auslösung von Symptomen einer larvalen Cyathostominose

    OpenAIRE

    Steinbach, Tanja

    2003-01-01

    Im Rahmen dieser Arbeit wird untersucht, ob bei Pferden durch die Gabe von Anthelminthika Symptome einer larvalen Cyathostominose ausgelöst werden können. Im Zentrum des Interesses stehen dabei die Anthelminthika Moxidectin und Fenbendazol, die aufgrund ihrer larviziden Wirksamkeit als Mittel der ersten Wahl für die kausale Therapie und Metaphylaxe der larvalen Cyathostominose angesehen werden. Der Versuch wird an 24 Ponyfohlen durchgeführt, die in die folgenden Gruppen unterteilt werden...

  18. Occupational radiation exposure of the personnel due to interventional radiology; Strahlenexposition des Personals bei interventionellen Massnahmen

    Energy Technology Data Exchange (ETDEWEB)

    Wucherer, M. [Klinikum der Stadt Nuernberg (Germany). Inst. fuer Medizinische Physik; Schmidt, T.; Loose, R. [Klinikum Nuernberg-Nord (Germany). Inst. fuer Diagnostische und Interventionelle Radiologie

    2000-07-01

    Applications of interventional radiology continue to be on an upward trend, some countries reporting a 100% increase within 2-4 years, so that the resulting radiation exposure of both patients and personnel is an issue of increasing importance. Whereas those applications in general are of advantage for the patients, they mean just a further health hazard for the medical personnel. It is therefore necessary to exploit all available means to reduce the occupational doses. Modern interventional radiology systems offer a range of measures for this purpose, as e.g. last-image-hold, or pulsed modes. Special attention has to be given to the exposure of hand and head. Particularly the hand is closest to the useful beam, and it should be a mandatory requirement to wear film rings. (orig./CB) [German] Interventionelle Massnahmen weisen immer noch eine Steigerungstendenz auf, teilweise wird in manchen Laendern von einer Verdopplungsrate von 2-4 Jahren berichtet. Eventuelle Folgen der interventionellen Massnahmen, naemlich die damit verbundene Strahlenexposition fuer Patient und Personal, werden zunehmend problematisiert. Waehrend der Patient einen unmittelbaren Nutzen von dem meist miminal invasiven Eingriff hat, ist dies beim Personal nicht der Fall. Es muessen deswegen, besonders beim Untersuchungspersonal, alle Moeglichkeiten ausgeschoepft werden, die Exposition zu reduzieren. Neben den ueblichen bekannten Methoden sind bei modernen Anlagen weitere Massnahmen moeglich. Hierzu zaehlen z.B. Speicherung des letzten Bildes, strahlungslose Einblendung, gepulste Durchleuchtung usw. In Einzelfaellen hat die Exposition des Personals die Jahresgrenzwerte erreicht. Besonderer Aufmerksamkeit ist bei interventionellen Massnahmen der Exposition von Hand und Kopf zu widmen. Die Hand ist, vor allem bei der Punktion und Kathetermanipulation, nahe dem Nutzstrahlenbuendel. Es ist deswegen zu fordern, dass bei den interventionellen Massnahmen Fingerringdosimeter getragen werden. (orig.)

  19. Delir, postoperative kognitive Verschlechterung und Charles Bonnet-Syndrom bei Patienten mit Kataraktoperationen

    OpenAIRE

    Hämmerl, Thomas

    2005-01-01

    In der Klinik für Augenheilkunde an der TU München wurden 92 Patienten mit Kataraktoperationen zu Delir, postoperativer kognitiver Verschlechterung und Charles Bonnet-Syndrom untersucht. Ein Patient hatte ein Delir bei Aufnahme, keiner entwickelte ein postoperatives Delir. Eine Risikogruppe für einen komplizierten postoperativen Verlauf stellten die Patienten mit präoperativer kognitiver Beeinträchtigung (n=11) und die Patienten mit postoperativer kognitiver Verschlechterung (n=8) dar. Risiko...

  20. Funktionsanalyse der rechten Herzkammer bei Kindern mit angeborenen Herzfehlern mithilfe der Conductance-Technik

    Directory of Open Access Journals (Sweden)

    Apitz C

    2009-01-01

    Full Text Available Hintergrund: Die komplexe Anatomie und die Abhängigkeit von Vor- und Nachlast machen die Bestimmung der rechtsventrikulären Funktion zu einer diagnostischen Herausforderung. Die sogenannte Conductance-Katheter-Technik erlaubt die zuverlässige Bestimmung der Funktion der linken Herzkammer. Ziel unserer Studie war die Evaluation der Conductance-Technik für die Funktionsanalyse des rechten Ventrikels. Patienten und Methode: Bei 13 pädiatrischen Patienten wurden nach Operation einer rechtsventrikulären Ausflussbahnobstruktion im Säuglings- bzw. Kleinkindalter Druck-Volumen-Kurven des rechten Ventrikels im Lebensalter von im Mittel 12,7 Jahren (7,5–17,9 Jahre mithilfe von Conductance-Kathetern aufgezeichnet. Als Maß für die myokardiale Kontraktilität des rechten Ventrikels wurde die endsystolische Druck- Volumen-Beziehung (Elastance unter Reduktion der Vorlast durch kurzzeitige Inflation eines Ballonkatheters in der unteren Hohlvene bestimmt. Zur Untersuchung der kontraktilen Reserve diente die Steigerung der Elastance während intravenöser Applikation von Dobutamin. Ergebnisse: Mithilfe der Conductance-Technik konnten bei allen Patienten reproduzierbare Druckvolumenkurven des rechten Ventrikels erhoben werden. Ernsthafte Nebenwirkungen traten während der Untersuchung nicht auf. Dobutamin führte im Vergleich zu den Ruhebedingungen zu einem signifikanten Anstieg der systolischen Funktionsparameter dP/dt max und der endsystolischen Elastance. Schlussfolgerung: Die Conductance-Technik ermöglicht auch bei der rechten Herzkammer die lastunabhängige Quantifizierung der myokardialen Kontraktilität und der kontraktilen Reserve und liefert damit bei Patienten mit angeborenen Herzfehlern zusätzliche Informationen zur verbesserten Beurteilung der Funktion des rechten Ventrikels.

  1. Scintigraphic assessment of renal function in a case of renal dystopia; Szintigraphische Funktionsberechnung bei renaler Lageanomalie

    Energy Technology Data Exchange (ETDEWEB)

    Pilgrim, S. [Gemeinschaftspraxis fuer Nuklearmedizin, Luebeck (Germany)

    1998-06-01

    In patients with renal dystopia radionuclide urography in commonly used technique may yield inaccurate results concerning split renal function. In a case of unilateral pelvic kidney a simple strategy to avoid this methodical error is demonstrated. (orig.) [Deutsch] Am Fallbeispiel eines Patienten mit einseitiger Beckenniere wird dargestellt, dass bei einer Lageanomalie und Anwendung der renalen Funktionsszintigraphie in ueblicher Technik eine deutliche Fehleinschaetzung der seitengetrennten Funktionsanteile resultieren kann. Ein einfaches Verfahren zur Vermeidung dieses Bestimmungsfehlers wird aufgezeigt. (orig.)

  2. Dimensionsgenauigkeit von Abformmaterialien bei der offenen und geschlossenen Implantatabformung zweier unterschiedlicher Implantatsysteme

    OpenAIRE

    Weskott, Katharina

    2011-01-01

    In der vorliegenden Studie wurde die Dimensionsgenauigkeit von Abformmaterialien bei der offenen und geschlossenen Implantatabformung in Zusammenhang mit den beiden Implantatsystemen Straumann (Freiburg) und BEGO (Bremen) untersucht. Die Besonderheit dieser Studie bestand zum einen in der Gegenüberstellung der beiden Implantatsysteme, da bislang noch kein direkter Vergleich unterschiedlicher Implantatsysteme in der Literatur beschrieben wurde. Zum anderen aber auch wurden in dieser Studie zus...

  3. Erfassung und Trainierbarkeit der posturalen Kontrolle und Modulation des Gangbildes bei Patienten mit Morbus Parkinson

    OpenAIRE

    2015-01-01

    Die vorliegende Arbeit gliedert sich in drei Teile. Zunächst geht es um die Erfassung der posturalen Instabilität bei Patienten mit Morbus Parkinson. Es wurde ein klinischer Gleichgewichtstest (Fullerton Advanced Balance (FAB) Scale) zur Erhebung der posturalen Kontrolle validiert und mit der Berg Balance Scale und dem Mini-Balance Evaluation System Test (Mini-BESTest) verglichen. Hierfür wurden 85 Parkinsonpatienten eingeschlossen und untersucht. Es konnte gezeigt werden, dass die FAB Sc...

  4. Wirksamkeit der Aromatherapie auf Angst bei Krebspatienten: systematische Literaturübersicht

    OpenAIRE

    Kryeziu, Ardijana; Jossen, Renata

    2016-01-01

    Problembeschreibung: Weltweit stellt Krebs ein weit verbreitetes Problem und eine häufige Todesursache dar. Bei einer Krebserkrankung treten körperliche und psychische Symptome auf. Eine Hauptbelastung der Betroffenen stellt die Angst dar. Ängste können medikamentös mit Anxiolytika behandelt werden. Trotzdem muss beachtet werden, dass Anxiolytika mit Nebenwirkungen oder einer Abhängigkeitsentwicklung verbunden sind. Deshalb ist es wichtig, zusätzliche nichtmedikamentöse Pflegeinterventi...

  5. Identifikation kognitiver Subgruppen bei der bipolaren Störung und Evaluation eines kognitiven Remediationsprogramms

    OpenAIRE

    Volkert, Julia

    2015-01-01

    Die bipolare Störung ist eine psychische Erkrankung, die sich durch wiederkehrende depressive und (hypo-) manische Phasen auszeichnet. Neben Stimmungsschwankungen leiden viele Patienten unter kognitiven Beeinträchtigungen, die nicht nur während akuter Episoden, sondern auch in der Remission, d.h. in euthymer Stimmungslage persistieren. Die vorliegende Arbeit beschäftigte sich mit den klinischen Korrelaten von kognitiven Defiziten und der Effektivität eines kognitiven Trainings bei bipolaren P...

  6. Mg++-Stoffwechselkorrelationen als Diagnose und Prognose beim Sport und bei Hypertonikern

    Directory of Open Access Journals (Sweden)

    Porta S

    2012-01-01

    Full Text Available Anhand eines Vergleichs der Daten dreier verschiedener Untersuchungen konnten wir demonstrieren, dass Veränderungen von ionisiertem Magnesium im Blut sowohl mit metabolischen Veränderungen als auch mit diastolischen und systolischen Blutdruckveränderungen korrelieren. Zuerst gelang es darzulegen, dass man imstande ist, durch die Bestimmung von Mg++ zusammen mit pH, Laktat und Leistungspunkten bei einem sportlichen Wettbewerb schon vor dem Bewerb anhand einer Mg++/pH-Korrelation die Chancen für anschließendes erfolgreiches Abschneiden vorherzusagen [1, 2]. Untersuchungen dieser Werte nach dem Bewerb gestatteten durch korrelative Analysen von Mg++-Veränderungen, Leistungspunkten und Laktatveränderungen einen tieferen Einblick in das Anstrengungs- Erfolgs-Verhältnis der Teilnehmer. Ähnlich den Resultaten beim Sport konnten durch Korrelation von Mg++ und diastolischem RR nach dem Test die signifikant-prognostischen Wirkungen der Mg++-Bestimmung gezeigt werden. Ähnlich wie beim Verhältnis zwischen Mg++ und Leistungspunkten zeigten auch hier diejenigen Patienten mit den geringsten Mg++-Abweichungen nach Provokation [1–3] auch die geringsten erregungsbedingten Veränderungen von diastolischem RR und Herzfrequenz durch den Test. Schließlich konnten wir bei 300 hypertonen Diabetikern zeigen, dass Blutzuckerveränderungen im Rahmen eines Glukoseprofils abhängig vom systolischen Blutdruck sind und eng mit Mg++-Veränderungen einhergehen, was einige neue Gedanken über den Mechanismus des Elektrolytverlusts bei Typ-2-Diabetikern und die Rolle des Blutdrucks bei Blutzuckerschwankungen zulässt [4–6].

  7. Mg++-Stoffwechselkorrelationen als Diagnose und Prognose beim Sport und bei Hypertonikern

    OpenAIRE

    2012-01-01

    Anhand eines Vergleichs der Daten dreier verschiedener Untersuchungen konnten wir demonstrieren, dass Veränderungen von ionisiertem Magnesium im Blut sowohl mit metabolischen Veränderungen als auch mit diastolischen und systolischen Blutdruckveränderungen korrelieren. Zuerst gelang es darzulegen, dass man imstande ist, durch die Bestimmung von Mg++ zusammen mit pH, Laktat und Leistungspunkten bei einem sportlichen Wettbewerb schon vor dem Bewerb anhand einer Mg++/pH-Korrelation di...

  8. Ergebnisse der dorsalen Spondylodese bei Frakturen des dorsolumbalen Übergangs

    OpenAIRE

    Ramzy, Magdy

    2002-01-01

    Ziel der vorliegenden Arbeit ist es, die Technik der dorsalen Spondylodese bei Frakturen des dorsolumbalen Überganges anhand von Komplikationen und Behandlungsergebnissen zu beurteilen. Es wurden in dieser retrospektiven Untersuchung 161 Patienten (60% männlich, 40% weiblich) eingeschlossen, die in den Jahren 1985 bis 1994 an der Unfallchirurgie Bergmannsheil Bochum behandelt wurden. 142 dieser Patienten wurden in standardisierter Technik durch dorsale Spondylodes mit internem Fix...

  9. Entwicklung und Evaluation eines intersektoralen und multidimensionalen Programms zur Adhärenzverbesserung bei psychiatrischen Patienten

    OpenAIRE

    2016-01-01

    Die psychiatrische Pharmakotherapie weist Risikofaktoren für Non-Adhärenz, wie langfristige Rezidivprophylaxen und unvermeidbare Nebenwirkungen, auf. Zusammen mit einer oft ungenügenden Therapie- und Krankheitseinsicht sowie einer individuellen Wahrnehmung von Risiken der Psychopharmaka durch den Patienten führt dies bei 20% bis 70% zu einem frühzeitigen Therapieabbruch. Die Folgen umfassen nicht nur Rückfälle, Krankenhauseinweisungen und höheren Kosten im Gesundheitssystem, sondern sogar ein...

  10. Fragmentbefestigung bei zervikalen Wurzelfrakturen - Eine In-vitro-Untersuchung zur Verbundfestigkeit verschiedener Dentinadhäsivsysteme -

    OpenAIRE

    Heuchemer, Elmar

    2008-01-01

    Traumatische Verletzungen der Frontzähne treten bei Kindern und Jugendlichen zunehmend häufiger auf. Im jugendlichen Gebiss ist die prothetische Versorgung eines zervikal frakturierten Zahnes aufgrund des nicht abgeschlossenen Kiefer- und Wurzelwachstums nicht möglich. Kompositaufbau oder Fragmentwiederbefestigung sind Möglichkeiten den Zahn mit einer guten Ästhetik zu erhalten. Ziel dieser Arbeit war es herauszufinden, ob verschiedene Adhäsivsysteme signifikante Unterschiede in der Bruchfest...

  11. Generalized EPID calibration for in vivo transit dosimetry.

    Science.gov (United States)

    Fidanzio, Andrea; Cilla, Savino; Greco, Francesca; Gargiulo, Laura; Azario, Luigi; Sabatino, Domenico; Piermattei, Angelo

    2011-01-01

    Many researchers are studying new in vivo dosimetry methods based on the use of Elelctronic portal imaging devices (EPIDs) that are simple and efficient in their daily use. However the need of time consuming implementation measurements with solid water phantoms for the in vivo dosimetry implementation can discourage someone in their use. In this paper a procedure has been proposed to calibrate aSi EPIDs for in vivo transit dosimetry. The dosimetric equivalence of three aSi Varian EPIDs has been investigated in terms of signal reproducibility and long term stability, signal linearity with MU and dose per pulse and signal dependence on the field dimensions. The signal reproducibility was within ± 0.5% (2SD), while the long term signal stability has been maintained well within ± 2%. The signal linearity with the monitor units (MU) was within ± 2% and within ± 0.5% for the EPIDs controlled by the IAS 2, and IAS 3 respectively. In particular it was verified that the correction factor for the signal linearity with the monitor units, k(lin), is independent of the beam quality, and the dose per pulse absorbed by the EPID. For 6, 10 and 15 MV photon beams, a generalized set of correlation functions F(TPR,w,L) and empirical factors f(TPR,d,L) as a function of the Tissue Phantom Ratio (TPR), the phantom thickness, w, the square field side, L, and the distance, d, between the phantom mid-plane and the isocentre were determined to reconstruct the isocenter dose. The tolerance levels of the present in vivo dosimetry method ranged between ± 5% and ± 6% depending on the tumor body location. In conclusion, the procedure proposed, that use generalized correlation functions, reduces the effort for the in vivo dosimetry method implementation for those photon beams with TPR within ± 0.3% as respect those here used.

  12. Vitex-agnus-castus-Extrakt (Ze 440 zur Symptombehandlung bei Frauen mit menstruellen Zyklusstörungen

    Directory of Open Access Journals (Sweden)

    Eltbogen R

    2015-01-01

    Full Text Available Ziel: Diese nichtinterventionelle Beobachtungsstudie (NIS wurde von Schweizer Gynäkologen und Allgemeinmedizinern im Rahmen der üblichen ärztlichen Grundversorgung durchgeführt. Das Ziel der NIS war es, die Wirksamkeit und Sicherheit von Vitex-agnus-castus-(VAC Extrakt (Ze 440: premens, Zeller Medical AG, Romanshorn, Schweiz bei Frauen, die unter menstruellen Zyklusstörungen wie Polymenorrhö, Oligomenorrhö oder Amenorrhö litten, zu untersuchen. Methode: Insgesamt 211 Patientinnen nahmen an dieser NIS teil. Symptome, die mit menstruellen Zyklusstörungen („menstrual cycle irregularities“ [MCIs] und der Menstruationsblutung in Verbindung stehen, wurden bei einer Erstuntersuchung („baseline visit“ [BV] und einer Kontrolluntersuchung („follow-up visit“ [FV] nach Behandlung mit VAC-Extrakt über einen Zeitraum von 3 aufeinanderfolgenden Menstruationszyklen beurteilt. Ergebnisse: Der Anteil der Patientinnen, bei denen eine Beschwerdefreiheit oder eine Besserung der MCIs (insgesamt und spezifischer Beschwerdebilder wie Polymenorrhö, Oligomenorrhö und Amenorrhö erzielt werden konnte, lag bei der FV bei 79–85 %. Bei Symptomen im Zusammenhang mit der Menstruationsblutung wie Dysmenorrhö, Zwischenblutungen, Hypermenorrhö, Menometrorrhagie, Ovulationsblutung, präoder postmenstrueller Blutung betrug der Anteil der Patientinnen, bei denen ein Rückgang oder eine Besserung festgestellt wurde, bei der FV zwischen 60 und 88 %. Von 53 Patientinnen, die bei der BV von einem unerfüllten Kinderwunsch berichteten, wurden 12 Frauen (23 % während der Behandlung mit VAC-Extrakt schwanger. Bei der FV waren 91 % der Ärzte und 92 % der Patientinnen mit den erzielten Behandlungsergebnissen „zufrieden“ oder „sehr zufrieden“ und 80 % der Patientinnen bestätigten, dass sie gerne mit der Behandlung mit VAC-Extrakt fortfahren wollen. Fazit: Diese Beobachtungsstudie im Bereich der ärztlichen Grundversorgung ergab, dass die Behandlung mit VAC

  13. Experimental Study on the Precise Orbit Determination of the BeiDou Navigation Satellite System

    Directory of Open Access Journals (Sweden)

    Jens Wickert

    2013-03-01

    Full Text Available The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO, five Inclined Geosynchronous Orbit (IGSO satellites and four Medium Earth Orbit (MEO satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better.

  14. Neuere Untersuchungen zur Prädiktion von EEG-Signalen bei Epilepsie

    Science.gov (United States)

    Niederhöfer, C.; Tetzlaff, R.

    2007-06-01

    Seit einigen Jahren ist die Analyse von EEG-Signalen bei Epilepsie Gegenstand zahlreicher wissenschaftlicher Arbeiten; Zielvorstellung ist dabei die Entwicklung von Verfahren zur Erkennung eines möglichen Voranfallszustandes. Im Vordergrund steht beispielsweise die Approximation einer so genannten effektiven Korrelationsdimension, die Bestimmung der maximalen Lyapunov-Exponenten, Detektionsverfahren für Muster bei Zellularen Nichtlinearen Netzwerken, die Bestimmung der mittleren Phasenkohärenz und Verfahren zur nichtlinearen Prädiktion von EEG-Signalen. Trotz umfangreicher Bemühungen kann bis heute eine Erkennung von Anfallsvorboten mit einer Sensitivität und Spezifität, die eine automatisierte Anfallsvorhersage ermöglichen würde, noch nicht durchgeführt werden. In diesem Beitrag werden neue Ergebnisse zur Prädiktion von EEG-Signalen bei Epilepsie vorgestellt. Dabei werden Signale, welche mittels intrakranieller electrocorticographischer (ECoG) und stereoelectroencephalographischer (SEEG) Ableitungen registriert wurden, segmentweise analysiert. Unter der Annahme, dass sich Änderungen des Systems ,,Gehirn" als Änderungen im Prädiktor, d.h. in seinen Systemparametern widerspiegeln, könnte eine nähere Betrachtung der Prädiktoreigenschaften zu einer Erkennung von Anfallsvorboten führen.

  15. Neuere Untersuchungen zur Prädiktion von EEG-Signalen bei Epilepsie

    Directory of Open Access Journals (Sweden)

    C. Niederhöfer

    2007-06-01

    Full Text Available Seit einigen Jahren ist die Analyse von EEG-Signalen bei Epilepsie Gegenstand zahlreicher wissenschaftlicher Arbeiten; Zielvorstellung ist dabei die Entwicklung von Verfahren zur Erkennung eines möglichen Voranfallszustandes. Im Vordergrund steht beispielsweise die Approximation einer so genannten effektiven Korrelationsdimension, die Bestimmung der maximalen Lyapunov-Exponenten, Detektionsverfahren für Muster bei Zellularen Nichtlinearen Netzwerken, die Bestimmung der mittleren Phasenkohärenz und Verfahren zur nichtlinearen Prädiktion von EEG-Signalen. Trotz umfangreicher Bemühungen kann bis heute eine Erkennung von Anfallsvorboten mit einer Sensitivität und Spezifität, die eine automatisierte Anfallsvorhersage ermöglichen würde, noch nicht durchgeführt werden. In diesem Beitrag werden neue Ergebnisse zur Prädiktion von EEG-Signalen bei Epilepsie vorgestellt. Dabei werden Signale, welche mittels intrakranieller electrocorticographischer (ECoG und stereoelectroencephalographischer (SEEG Ableitungen registriert wurden, segmentweise analysiert. Unter der Annahme, dass sich Änderungen des Systems ,,Gehirn" als Änderungen im Prädiktor, d.h. in seinen Systemparametern widerspiegeln, könnte eine nähere Betrachtung der Prädiktoreigenschaften zu einer Erkennung von Anfallsvorboten führen.

  16. White matter alterations in neurodegenerative and vascular dementia; Marklagerveraenderungen bei neurodegenerativen und vaskulaeren Demenzerkrankungen

    Energy Technology Data Exchange (ETDEWEB)

    Supprian, T. [Arbeitsgruppe Gerontopsychiatrie, Universitaets-Nervenklinik Homburg (Germany); Arbeitsgruppe Gerontopsychiatrie, Universitaets-Nervenklinik, Psychiatrie und Psychotherapie, 66421, Homburg (Germany); Kessler, H.; Falkai, P. [Arbeitsgruppe Gerontopsychiatrie, Universitaets-Nervenklinik Homburg (Germany); Retz, W.; Roesler, M. [Arbeitsgruppe Gerontopsychiatrie, Universitaets-Nervenklinik Homburg (Germany); Institut fuer gerichtliche Psychologie und Psychiatrie, Universitaet des Saarlandes, Homburg (Germany); Grunwald, I.; Reith, W. [Abteilung fuer Neuroradiologie, Universitaetskliniken des Saarlandes, Homburg (Germany)

    2003-07-01

    Due to a significant overlap of the two syndromes, differentiation of degenerative dementia of the Alzheimer-type from vascular dementia may be difficult even when imaging studies are available. White matter changes occur in many patients suffering from Alzheimer's disease. Little is known about the impact of white matter changes on the course and clinical presentation of Alzheimer's disease. High sensitivity of MRI in the detection of white matter alterations may account for over-diagnosing vascular dementia. The clinical significance of white matter alterations in dementia is still a matter of debate. The article reviews current concepts about the role of white matter alterations in dementia. (orig.) [German] Die Zuordnung einer Demenzerkrankung zu einem neurodegenerativen Pathomechanismus, wie der Demenz vom Alzheimer-Typ (DAT) oder einem vaskulaeren Pathomechanismus, kann trotz der Verfuegbarkeit bildgebender Verfahren Probleme bereiten. Ueberlappungen neurodegenerativer und vaskulaerer Mechanismen sind haeufig. Mikroangiopathische Veraenderungen des Marklagers finden sich bei einem hohen Anteil von Patienten mit der klinischen Verlaufsform einer Demenz vom Alzheimer-Typ. Es ist unklar, ob es sich um eine Koinzidenz zweier Pathomechanismen handelt oder ob eine wechselseitige Beeinflussung stattfindet. Die hohe Sensitivitaet der Magnetresonanztomographie bei der Erfassung mikroangiopathischer Veraenderungen des Marklagers koennte dazu fuehren, dass zu vaskulaere Demenzerkrankungen haeufig diagnostiziert werden. Der Einfluss mikroangiopathischer Veraenderungen des Marklagers auf den Demenzverlauf wird kontrovers diskutiert. Die vorgelegte Arbeit gibt eine Uebersicht ueber die aktuellen Konzepte zum Stellenwert von Marklagerveraenderungen bei Demenzerkrankungen. (orig.)

  17. Butterfly valves and other valves under strong cavitation conditions; Drosselklappen und andere Absperrorgane bei starker Kavitation

    Energy Technology Data Exchange (ETDEWEB)

    Logar, R. [TU Graz (Austria). Inst. fuer Hydraulische Stroemungsmaschinen

    2008-06-15

    This article was written to commemorate my doctoral thesis supervisor, Univ.Prof. Dr. Gerhard Ziegler, on whose ideas this work is based. Cavitation is a well-known phenomenon in waterpower and other hydraulic flow applications. In analogy to the behaviour of ''chocked flow'' in a venturi tube - the flow characteristic of valves under strong cavitation conditions is analytically expressed. This analytical law agrees very well with our experimental results. (orig.) [German] Bei der Modellmessung fuer eine grosse Drosselklappe ist die Frage aufgetaucht, wie sich die Durchfluss-, Momenten- und Kraftbeiwerte bei sehr starker Kavitation verhalten. Univ. Prof. Dr. G. Ziegler, damaliger Vorstand des Institutes fuer Hydraulische Stroemungsmaschinen an der Technischen Universitaet Graz, hatte die Idee zu einem analytischen Ansatz und legte in einem nicht veroeffentlichtem Bericht [24] seine Vorstellungen dar. Dieser Bericht entstand im Gedenken an meinen Doktorvater Prof. Ziegler. Kavitation ist ein bekanntes Phaenomen auf dem Gebiet der Wasserkraft und bei vielen anderen Anwendungen mit Fluessigkeitsstroemungen. In Analogie zum Verhalten der ''blockierten Stroemung'' eines Venturirohres wird das Durchflussverhalten von Drosselklappen analytisch beschrieben. Dieser analytische Ansatz stimmt mit unseren experimentellen Ergebnissen sehr gut ueberein. (orig.)

  18. GENII (Generation II): The Hanford Environmental Radiation Dosimetry Software System: Volume 3, Code maintenance manual: Hanford Environmental Dosimetry Upgrade Project

    Energy Technology Data Exchange (ETDEWEB)

    Napier, B.A.; Peloquin, R.A.; Strenge, D.L.; Ramsdell, J.V.

    1988-09-01

    The Hanford Environmental Dosimetry Upgrade Project was undertaken to incorporate the internal dosimetry models recommended by the International Commission on Radiological Protection (ICRP) in updated versions of the environmental pathway analysis models used at Hanford. The resulting second generation of Hanford environmental dosimetry computer codes is compiled in the Hanford Environmental Dosimetry System (Generation II, or GENII). This coupled system of computer codes is intended for analysis of environmental contamination resulting from acute or chronic releases to, or initial contamination of, air, water, or soil, on through the calculation of radiation doses to individuals or populations. GENII is described in three volumes of documentation. This volume is a Code Maintenance Manual for the serious user, including code logic diagrams, global dictionary, worksheets to assist with hand calculations, and listings of the code and its associated data libraries. The first volume describes the theoretical considerations of the system. The second volume is a Users' Manual, providing code structure, users' instructions, required system configurations, and QA-related topics. 7 figs., 5 tabs.

  19. Performance of the CEDS Accident Dosimetry System at the 1995 Los Alamos National Laboratory Nuclear Accident Dosimetry Intercomparison

    Energy Technology Data Exchange (ETDEWEB)

    McMahan, K.L.; Schwanke, L.J.

    1996-12-01

    In July 1995, LANL hosted an accident dosimetry intercomparison. When all reactors on the Oak Ridge Reservation were idled in 1988, the Health Physics Research Reactor (HPRR), which had been used for 22 previous intercomparisons dating from 1965, was shut down for an indefinite period. The LANL group began characterization of two critical assemblies for dosimetry purposes. As a result, NAD-23 was conceived and 10 DOE facilities accepted invitations to participate in the intercomparison. This report is a summary of the performance of one of the participants, the Centralized External Dosimetry System (CEDS). The CEDS is a cooperative personnel dosimetry arrangement between three DOE sites in Oak Ridge, Tennessee. Many successes and failures are reported herein. Generally, the TL dosimeters performed poorly and always over-reported the delivered dose. The TLD processing procedures contain efforts that would lead to large biases in the reported absorbed dose, and omit several key steps in the TLD reading process. The supralinear behavior of lithium fluoride (LiF) has not been characterized for this particular dosimeter and application (i.e., in high-dose mixed neutron/gamma fields). The use of TLD materials may also be precluded given the limitations of the LiF material itself, the TLD reading system, and the upper dose level to which accident dosimetry systems are required to perform as set forth in DOE regulations. The indium foil results confirm the expected inability of that material to predict the magnitude of the wearer`s dose reliably, although it is quite suitable as a quick-sort material. Biological sample (hair) results were above the minimum detectable activity (MDA) for only one of the tests. Several questions as to the best methods for sample handling and processing remain.

  20. Effects of spin-orbit coupling on laser cooling of BeI and MgI

    Energy Technology Data Exchange (ETDEWEB)

    Wan, Mingjie, E-mail: wanmingjie1983@sina.com; Huang, Duohui; Shao, Juxiang; Li, Yuanyuan [Computational Physics Key Laboratory of Sichuan Province, Yibin University, Yibin 644007 (China); Yu, You [College of Optoelectronic Technology, Chengdu University of Information Technology, Chengdu 610225 (China); Li, Song [College of Physical Science and Technology, Yangtze University, Jingzhou 434023 (China)

    2015-10-28

    We present the ab initio study of spin-orbit coupling effects on laser cooling of BeI and MgI molecules. Potential energy curves for the X{sup 2}Σ{sup +}{sub 1/2}, A{sup 2}Π{sub 1/2,3/2}, and 2{sup 2}Π{sub 3/2,1/2} states are calculated using multi-reference configuration interaction method plus Davidson corrections. Spectroscopic parameters of BeI and MgI are in excellent agreement with available experimental and theoretical values. The A{sup 2}Π{sub 3/2} state of MgI is a repulsive state. It is an unsuitable scheme for the A{sup 2}Π{sub 3/2}(υ′)← X{sup 2}Σ{sup +}{sub 1/2} (υ″) transition for laser cooling of MgI. Highly diagonally distributed Franck-Condon factors f{sub 00} for the A{sup 2}Π{sub 1/2,3/2} (υ′ = 0) ← X{sup 2}Σ{sup +}{sub 1/2} (υ″ = 0) transitions and suitable radiative lifetimes τ for the A{sup 2}Π{sub 1/2,3/2} (υ′ = 0) of BeI and MgI are obtained. Three laser wavelength drives are required for the A{sup 2}Π{sub 1/2,3/2}(υ′)←X{sup 2}Σ{sup +}{sub 1/2} (υ″) transitions of BeI and MgI. The proposed cooling wavelengths of BeI and MgI are both in the violet region. The results imply the feasibility of laser cooling of BeI and MgI, and that laser cooling of BeI is more possible.

  1. Effects of spin-orbit coupling on laser cooling of BeI and MgI.

    Science.gov (United States)

    Wan, Mingjie; Huang, Duohui; Shao, Juxiang; Yu, You; Li, Song; Li, Yuanyuan

    2015-10-28

    We present the ab initio study of spin-orbit coupling effects on laser cooling of BeI and MgI molecules. Potential energy curves for the X(2)Σ(+)(1/2), A(2)Π(1/2,3/2), and 2(2)Π(3/2,1/2) states are calculated using multi-reference configuration interaction method plus Davidson corrections. Spectroscopic parameters of BeI and MgI are in excellent agreement with available experimental and theoretical values. The A(2)Π(3/2) state of MgI is a repulsive state. It is an unsuitable scheme for the A(2)Π(3/2)(υ')← X(2)Σ(+)(1/2) (υ″) transition for laser cooling of MgI. Highly diagonally distributed Franck-Condon factors f00 for the A(2)Π(1/2,3/2) (υ' = 0) ← X(2)Σ(+)(1/2) (υ″ = 0) transitions and suitable radiative lifetimes τ for the A(2)Π(1/2,3/2) (υ' = 0) of BeI and MgI are obtained. Three laser wavelength drives are required for the A(2)Π(1/2,3/2)(υ')←X(2)Σ(+)(1/2) (υ″) transitions of BeI and MgI. The proposed cooling wavelengths of BeI and MgI are both in the violet region. The results imply the feasibility of laser cooling of BeI and MgI, and that laser cooling of BeI is more possible.

  2. Multimodale Diagnostik von Gallenwegsstenosen: Welche bildgebenden Verfahren brauchen wir bei Gallenwegsstenosen unklarer Ätiologie?

    Directory of Open Access Journals (Sweden)

    Meister T

    2011-01-01

    Full Text Available Die Diagnostik von Gallenwegserkrankungen ist aufgrund der Vielfalt der potenziellen Entitäten und der diagnostischen (und therapeutischen Optionen ein schwieriges Feld. Neben der eigentlichen Erkrankung spielen weitere Faktoren wie das Alter der Patienten, Begleiterkrankungen oder zu erwartende Interventionspflichtigkeit bei der Auswahl des diagnostischen Verfahrens eine wesentliche Rolle. Während beispielsweise bei potenzieller Interventionspflichtigkeit (Cholestase, Verdacht auf eine biliäre Candidiasis die Indikation zur ERCP relativ großzügig gestellt wird, sollte bei jungen Patienten mit erhöhten Cholestaseparametern zunächst eine weniger invasive Diagnostik (EUS, MRCP erfolgen. Auch im Zeitalter der „High-end“-Bildgebung bleibt die unklare Gallenwegsstenose eine immense Herausforderung. Neben der präoperativen histologischen/zytologischen Diagnosesicherung ist eine multimodale Bildgebung erforderlich. Gerade die Bestimmung der Tumorausdehnung eines Klatskin-Tumors bleibt mit sämtlichen derzeit verfügbaren bildgebenden Verfahren herausfordernd. Wo liegen die Perspektiven in der Diagnostik von Erkrankungen des pankreatobiliären Systems in der Zukunft? Wie oben dargestellt, sind vor allem die unklaren Gallenwegsstenosen auch weiterhin das Hauptproblem der Diagnostik. Ähnlich wie bereits beim transabdominellen Ultraschall realisiert, könnte in der Endosonographie eine weitere Verbesserung durch den Einsatz von Kontrastmitteln erzielt werden – gerade bei der immer noch sehr schwierigen Differenzierung zwischen malignen und benignen Pankreasläsionen [1–3]. Die Arbeitsgruppe um Dietrich konnte in einer Pilotstudie zeigen, dass Sensitivität und Spezifität von 73 % bzw. 83 % (konventionelle EUS durch den Einsatz von Kontrastmitteln auf 91 % bzw. 93 % gesteigert werden können [2]. Auf dem Gebiet der radiologischen (nuklearmedizinischen Fusionsbildgebung bleibt abzuwarten, inwiefern die Kombination aus PET und

  3. Furosemide urogram in patients with neobladder; Das Diureseurogramm bei Patienten mit Harnblasenersatz

    Energy Technology Data Exchange (ETDEWEB)

    Merkle, E.M. [Univ. Ulm (Germany). Abt. Radiologie; Aschoff, A.J. [Univ. Ulm (Germany). Abt. Radiologie; Bachor, R. [Univ. Ulm (Germany). Abt. fuer Urologie; Vogel, J. [Univ. Ulm (Germany). Abt. Radiologie; Merk, J. [Univ. Ulm (Germany). Abt. Radiologie; Brambs, H.J. [Univ. Ulm (Germany). Abt. Radiologie

    1996-11-01

    Purpose: To differentiate between urodynamically relevant obstruction and functionally unimportant dilation of the upper urinary tract in patients with neobladder using a modified furosemide urogram. Method: An excretory urogram with furosemide loading was carried out in 19 patients with neobladder and sonographically and urographically confirmed dilation of the upper urinary tract. Once strong contrasting of the renal pelves and calyces has been achieved, 20 mg of furosemide were applied and late radiographs were obtained at 15 min and 30 min, respectively. An obstruction was defined as increasing dilation of the renal pelves and calices during forced diuresis and lack of washout effect of the contrast medium. Results: In 32 cases, the renoureteral unit (RUU) was dilated on ultrasound. Of these, 25 RUU`s showed good emptyness of contrast medium upon stimulation of diuresis, six RUU`s returned a borderline findings, while one RUU was found to exhibit a decompensated anastomotic stenosis, which was dilated. Two further patients with bordeline findings were later treated surgically due to their pain symptoms. No patient required further preoperative diagnostic procedures. Conclusions: The modified furosemide urogram represents a cost-effective diagnostic orientation strategy in patients with neobladder and dilated renal pelves and calyses and is both well-tolerated by patients and meets with broad acceptance from the urologic staff. (orig.) [Deutsch] Ziel: Differenzierung zwischen urodynamisch relevanter Obstruktion und funktionell bedeutungsloser Dilatation des oberen Harntraktes bei Patienten mit Harnblasenersatz durch ein modifiziertes Diureseurogramm. Methodik: Bei 19 Patienten mit Harnableitung und sonographisch sowie urographisch nachgewiesener Erweiterung des oberen Harntraktes wurde ein Ausscheidungsurogramm mit Furosemidbelastung durchgefuehrt. Bei kraeftiger Kontrastierung des erweiterten Nierenbeckenkelchsystems (NBKS) wurden 20 mg Furosemid appliziert und

  4. EPR/PTFE dosimetry for test reactor environments

    Energy Technology Data Exchange (ETDEWEB)

    Vehar, D.W.; Griffin, P.J.; Quirk, T.J. [Sandia National Laboratories, Albuquerque, NM 87185-1146 (United States)

    2011-07-01

    The use of Electron Paramagnetic Resonance (EPR) spectroscopy with materials such as alanine is well established as a technique for measurement of ionizing radiation absorbed dose in photon and electron fields such as Co-60, high-energy bremsstrahlung and electron-beam fields [1]. In fact, EPR/Alanine dosimetry has become a routine transfer standard for national standards bodies such as NIST and NPL. In 1992 the Radiation Metrology Laboratory (RML) at Sandia National Laboratories implemented EPR/Alanine capabilities for use in routine and calibration activities at its Co-60 and pulsed-power facilities. At that time it also investigated the usefulness of the system for measurement of absorbed dose in the mixed neutron/photon environments of reactors such as the Sandia Pulsed Reactor and the Annular Core Research Reactor used for hardness testing of electronics. The RML concluded that the neutron response of alanine was a sufficiently high fraction of the overall dosimeter response that the resulting uncertainties in the photon dose would be unacceptably large for silicon-device testing. However, it also suggested that non-hydrogenous materials such as polytetrafluoroethylene (PTFE) would exhibit smaller neutron response and might be useful in mixed environments. Preliminary research with PTFE in photon environments indicated considerable promise, but further development was not pursued at that time. Because of renewed interest in absorbed dose measurements that could better define the individual contributions of photon and neutron components to the overall dose delivered to a test object, the RML has re-initiated the development of an EPR/PTFE dosimetry system. This effort consists of three stages: 1) Identification of PTFE materials that may be suitable for dosimetry applications. It was speculated that the inconsistency of EPR signatures in the earlier samples may have been due to variability in PTFE manufacturing processes. 2) Characterization of dosimetry in

  5. TU-F-201-01: General Aspects of Radiochromic Film Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Niroomand-Rad, A.

    2015-06-15

    Since the introduction of radiochromic films (RCF) for radiation dosimetry, the scope of RCF dosimetry has expanded steadily to include many medical applications, such as radiation therapy and diagnostic radiology. The AAPM Task Group (TG) 55 published a report on the recommendations for RCF dosimetry in 1998. As the technology is advancing rapidly, and its routine clinical use is expanding, TG 235 has been formed to provide an update to TG-55 on radiochromic film dosimetry. RCF dosimetry applications in clinical radiotherapy have become even more widespread, expanding from primarily brachytherapy and radiosurgery applications, and gravitating towards (but not limited to) external beam therapy (photon, electron and protons), such as quality assurance for IMRT, VMAT, Tomotherapy, SRS/SRT, and SBRT. In addition, RCF applications now extend to measurements of radiation dose in particle beams and patients undergoing medical exams, especially fluoroscopically guided interventional procedures and CT. The densitometers/scanners used for RCF dosimetry have also evolved from the He-Ne laser scanner to CCD-based scanners, including roller-based scanner, light box-based digital camera, and flatbed color scanner. More recently, multichannel RCF dosimetry introduced a new paradigm for external beam dose QA for its high accuracy and efficiency. This course covers in detail the recent advancements in RCF dosimetry. Learning Objectives: Introduce the paradigm shift on multichannel film dosimetry Outline the procedures to achieve accurate dosimetry with a RCF dosimetry system Provide comprehensive guidelines on RCF dosimetry for various clinical applications One of the speakers has a research agreement from Ashland Inc., the manufacturer of Gafchromic film.

  6. Dosimetry using HS GafChromic films the influence of readout light on sensitivity of dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Secerov, Bojana [Vinca Institute of Nuclear Sciences, Mike Alasa BB, Belgrade 11000 (Serbia); Dakovic, Marko [University of Belgrade, Faculty of Physical Chemistry, Studentski trg 12-16, Belgrade 11000 (Serbia); Borojevic, Nenad [National Cancer Research Center of Serbia, Pasterova 14, Belgrade 11000 (Serbia); Bacic, Goran, E-mail: ggbacic@ffh.bg.ac.r [University of Belgrade, Faculty of Physical Chemistry, Studentski trg 12-16, Belgrade 11000 (Serbia)

    2011-03-21

    Various forms of Gafchromic films that are increasingly used for dosimetry in radiotherapy offer the prospect of reproducible and accurate high-resolution two-dimensional dose measurements, but there are many unresolved issues regarding the optimal choice of densitometric procedure used for the film's optical density (OD) readout. There are conflicting requirements for scanners (sensitivity, availability, price) and commercial document scanners appears to be a reasonable option, hence we analyzed the measured sublinear dose response of these scanners. Using measured film absorption spectra we were able to make quantitative distinction between various factors affecting the sublinearity and to demonstrate that the dose response curve can be predicted for any selected light source used for scanning. We also used the commercial narrow bandpass filters in conjunction with document scanners to investigate whether such an inexpensive option can improve their sensitivity, but results were not encouraging. Finally, we analyzed the suitability of proposed fitting equations for the calibration of the dose response and found that their reliability largely depends on the dose range used for the calibration.

  7. Three-dimensional dosimetry using magnetic resonance imaging of polymer gel

    Energy Technology Data Exchange (ETDEWEB)

    Oh, Young Taek; Kang, Hae Jin; Kim, Mi Wha; Chun, Mi Son; Kang, Seung Hee [Ajou University School of Medicine, Suwon (Korea, Republic of); Suh, Chang Ok; Chu, Seong Sil; Seong, Jin Sil; Kim, Gwi Eon [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2002-09-15

    Three-dimensional radiation dosimetry using magnetic resonance imaging of polymer gel was recently introduced. This dosimetry system is based on radiation induced chain polymerization of acrylic monomers in a muscle equivalent gel and provide accurate 3 dimensional dose distribution. We planned this study to evaluate the clinical value of this 3-dimensional dosimetry. The polymer gel poured into a cylindrical glass flask and a spherical glass flask. The cylindrical test tubes were for dose response evaluation and the spherical flasks, which is comparable to the human head, were for isodose curves. T2 maps from MR images were calculated using software, IDL. Dose distributions have been displayed for dosimetry. The same spherical flask of gel and the same irradiation technique was used for film and TLD dosimetry and compared with each other. The R2 of the gel respond linearly with radiation doses in the range of 2 to 15 Gy. The repeated dosimetry of spherical gel showed the same isodose curves. The isodose curves were identical to dose distributions from treatment planning system especially high dose range. In addition, the gel dosimetry system showed comparable or superior results with the film and TLD dosimetry. The 3-dimensional dosimetry for conformal radiation therapy using MRI of polymer gel showed stable and accurate results. Although more studies are needed for convenient clinical application, it appears to be a useful tool for conformal radiation therapy.

  8. Phantom positioning variation in the Gamma Knife® Perfexion dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Nathalia Almeida; Potiens, Maria da Penha Albuquerque [Instituto de Pesquisas Energeticas e Nucleres (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Saraiva, Crystian [Hospital do Coracao, Sao Paulo, SP (Brazil)

    2015-07-01

    The use of small volume ionization chamber has become required for the dosimetry of equipment that use small radiation fields. A pinpoint ionization chamber is ideal for the dosimetry of a Gamma Knife® Perfexion (GKP) unit. In this work, this chamber was inserted into the phantom, and measurements were performed with the phantom in different positions, in order to verify if the change in the phantom positioning affects the dosimetry of the GKP. Three different phantom positions were performed. The variation in the result is within the range allowed for the dosimetry of a GKP equipment. (author)

  9. Application of biological dosimetry in accidental radiation exposure

    Energy Technology Data Exchange (ETDEWEB)

    Nosal, M.; Batora, I.; Kolesar, D.; Stojkovic, J. (Komenskeho Univ., Bratislava (Czechoslovakia). Lekarska Fakulta); Gaal, P.; Sklovsky, A. (Krajska Hygienicka Stanica, Bratislava (Czechoslovakia)); Cizova, O. (Sexuologicka Ambulancia KUNZ, Bratislava (Czechoslovakia))

    1982-03-01

    The case is described of accidental irradiation of a male person with /sup 137/Cs of an activity of 24.71 GBq. The first estimate induced a reasonable suspicion that the absorbed dose could be very high and life-threatening. On the other hand the clinical picture, usual laboratory examinations, findings in the fluorescent blood count, the analysis of chromosomal count of lymphocytes in the peripheral blood, the spermiogram, and the negative post-irradiation porphyrinuria suggested that the absorbed dose could be much lower than the original estimate. The results of dosimetry obtained after the reconstruction of the accident by measuring on a phantom revealed that the actual dose was very close to that presumed from the results of biological dosimetry during the first days of examination of the patient.

  10. Relative dosimetry by Ebt-3; Dosimetria relativa por EBT3

    Energy Technology Data Exchange (ETDEWEB)

    De Leon A, M. A.; Rivera M, T. [IPN, Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada, Av. Legaria 694, 11500 Mexico D. F. (Mexico); Hernandez O, J. O., E-mail: madla16@hotmail.com [Hospital General de Mexico, Dr. Balmis 148, Col. Doctores, 06726 Mexico D. F. (Mexico)

    2015-10-15

    In the present work relative dosimetry in two linear accelerator for radiation therapy was studied. Both Varian Oncology systems named Varian Clinac 2100-Cd and MLC Varian Clinac i X were used. Gaf Chromic Ebt-3 film was used. Measurements have been performed in a water equivalent phantom, using 6 MV and 18 MV photon beams on both Linacs. Both calibration and Electron irradiations were carried out with the ionization chamber placed at the isocenter, below a stack of solid water slabs, at the depth of dose maximum (D max), with a Source-to-Surface Distance (SSD) of 100 cm and a field size of 10 cm x 10 cm. Calibration and dosimetric measurements photons were carried out under IAEA-TRS 398 protocol. Results of relative dosimetry in the present work are discussed. (Author)

  11. ACS Algorithm in Discrete Ordinates for Pressure Vessel Dosimetry

    Directory of Open Access Journals (Sweden)

    Walters William

    2016-01-01

    Full Text Available The Adaptive Collision Source (ACS method can solve the Linear Boltzmann Equation (LBE more efficiently by adaptation of the angular quadrature order. This is similar to, and essentially an extension of, the first collision source method. Previously, the ACS methodology has been implemented into the TITAN discrete ordinates code, and has shown speedups of 2–4 on a simple test problem, with very little loss of accuracy (within a provided adaptive tolerance. This work examines the use of the ACS method for a more realistic problem: pressure vessel dosimetry with the VENUS-2 MOX-fuelled reactor dosimetry benchmark. The ACS method proved to be able to obtain accurate results while being approximately twice as efficient as using a constant quadrature in a standard source iteration scheme.

  12. Alternative statistical methods for cytogenetic radiation biological dosimetry

    CERN Document Server

    Fornalski, Krzysztof Wojciech

    2014-01-01

    The paper presents alternative statistical methods for biological dosimetry, such as the Bayesian and Monte Carlo method. The classical Gaussian and robust Bayesian fit algorithms for the linear, linear-quadratic as well as saturated and critical calibration curves are described. The Bayesian model selection algorithm for those curves is also presented. In addition, five methods of dose estimation for a mixed neutron and gamma irradiation field were described: two classical methods, two Bayesian methods and one Monte Carlo method. Bayesian methods were also enhanced and generalized for situations with many types of mixed radiation. All algorithms were presented in easy-to-use form, which can be applied to any computational programming language. The presented algorithm is universal, although it was originally dedicated to cytogenetic biological dosimetry of victims of a nuclear reactor accident.

  13. On multichannel film dosimetry with channel-independent perturbations

    CERN Document Server

    Méndez, Ignasi; Hudej, Rihard; Strojnik, Andrej; Casar, Božidar

    2014-01-01

    Purpose: Different multichannel methods for film dosimetry have been proposed in the literature. Two of them are the weighted mean method and the method put forth by Micke et al and Mayer et al. The purpose of this work was to compare their results and to develop a generalized channel-independent perturbations framework in which both methods enter as special cases. Methods: Four models of channel-independent perturbations were compared: weighted mean, Micke-Mayer method, uniform distribution and truncated normal distribution. A closed-form formula to calculate film doses and the associated Type B uncertainty for all four models was deduced. To evaluate the models, film dose distributions were compared with planned and measured dose distributions. At the same time, several elements of the dosimetry process were compared: film type EBT2 versus EBT3, different waiting-time windows, reflection mode versus transmission mode scanning, and planned versus measured dose distribution for film calibration and for gamma-...

  14. Medical radiation dosimetry theory of charged particle collision energy loss

    CERN Document Server

    McParland, Brian J

    2014-01-01

    Accurate radiation dosimetry is a requirement of radiation oncology, diagnostic radiology and nuclear medicine. It is necessary so as to satisfy the needs of patient safety, therapeutic and diagnostic optimisation, and retrospective epidemiological studies of the biological effects resulting from low absorbed doses of ionising radiation. The radiation absorbed dose received by the patient is the ultimate consequence of the transfer of kinetic energy through collisions between energetic charged particles and atoms of the tissue being traversed. Thus, the ability of the medical physicist to both measure and calculate accurately patient dosimetry demands a deep understanding of the physics of charged particle interactions with matter. Interestingly, the physics of charged particle energy loss has an almost exclusively theoretical basis, thus necessitating an advanced theoretical understanding of the subject in order to apply it appropriately to the clinical regime. ​ Each year, about one-third of the worl...

  15. Identification and dosimetry of irradiated walnuts (Juglans regia) using EPR

    Science.gov (United States)

    Maghraby, A.; Salama, E.; Sami, A.; Mansour, A.; El-Sayed, M.

    2012-03-01

    Electron paramagnetic resonance (EPR) is an easy, fast, and reliable tool for identification of irradiated food. Untreated nuts may encounter hazards of carrying several pathogens or microbial contamination; walnuts are of specific importance due to their nutritional and medicinal values, and hence walnut processing via gamma irradiation is a necessary step. EPR was employed for the identification and dosimetry of Cs-137 gamma-irradiated walnuts (shells and kernels). Several important parameters were studied, such as spectral features, microwave power dependence of signal intensities, and short- and long-term time dependences. Responses of walnut shells and kernels to different radiation doses in the range 0-10 kGy were investigated. Results confirmed that EPR is a suitable tool for the identification and dosimetry of irradiated walnuts using either their shells or only kernels.

  16. The specifics of dosimetry for food irradiation applications

    Science.gov (United States)

    Kuntz, Florent; Strasser, Alain

    2016-12-01

    Dose measurement applied to food irradiation is obviously a very important and critical aspect of this process. It is described in many standards and guides. The application of appropriate dosimetry tools is explained. This helps to ensure traceability of this measurement and number of dosimeters available on the market are well studied even though theirs response should be characterized while used in routine processing conditions. When employed in low energy radiation fields, these dosimeters may exhibit specific response compared to the usual Cobalt 60 source irradiation. Traceable calibration or correction factor assessment of this energy dependency is mandatory. It is to mention that the absorbed dose is measured in the dosimeter itself and unfortunately not in/on the food product. However, existing dosimetry systems fulfill all relevant requirements.

  17. Dosimetry using environmental and biological materials. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Haskell, E.; Kenner, G.; Hayes, R.

    1998-02-01

    This report summarizes a five year effort to improve the sensitivity and reliability of retrospective dosimetry methods, to collaborate with laboratories engaged in related research and to share the technology with startup laboratories seeking similar capabilities. This research program has focused on validation of electron paramagnetic resonance (EPR) as a dosimetry tool and on optimization of the technique by reducing the lower limits of detection, simplifying the process of sample preparation and analysis and speeding analysis to allow greater throughput in routine measurement situations. The authors have investigated the dosimetric signal of hard tissues in enamel, deorganified dentin, synthetic carbonated apatites and synthetic hydroxyapatite. This research has resulted in a total of 27 manuscripts which have been published, are in press, or have been submitted for publication. Of these manuscripts, 14 are included in this report and were indexed separately for inclusion in the data base.

  18. Radiation Protection and Dosimetry An Introduction to Health Physics

    CERN Document Server

    Stabin, Michael G

    2007-01-01

    This comprehensive text provides an overview of all relevant topics in the field of radiation protection (health physics). Radiation Protection and Dosimetry serves as an essential handbook for practicing health physics professionals, and is also ideal as a teaching text for courses at the university level. The book is organized to introduce the reader to basic principles of radiation decay and interactions, to review current knowledge and historical aspects of the biological effects of radiation, and to cover important operational topics such as radiation shielding and dosimetry. In addition to presenting the most up to date treatment of the topics and references to the literature, most chapters contain numerical problems with their solutions for use in teaching or self assessment. One chapter is devoted to Environmental Health Physics, which was written in collaboration with leading professionals in the area.

  19. Computer simulations for internal dosimetry using voxel models.

    Science.gov (United States)

    Kinase, Sakae; Mohammadi, Akram; Takahashi, Masa; Saito, Kimiaki; Zankl, Maria; Kramer, Richard

    2011-07-01

    In the Japan Atomic Energy Agency, several studies have been conducted on the use of voxel models for internal dosimetry. Absorbed fractions (AFs) and S values have been evaluated for preclinical assessments of radiopharmaceuticals using human voxel models and a mouse voxel model. Computational calibration of in vivo measurement system has been also made using Japanese and Caucasian voxel models. In addition, for radiation protection of the environment, AFs have been evaluated using a frog voxel model. Each study was performed by using Monte Carlo simulations. Consequently, it was concluded that these data of Monte Carlo simulations and voxel models could adequately reproduce measurement results. Voxel models were found to be a significant tool for internal dosimetry since the models are anatomically realistic. This fact indicates that several studies on correction of the in vivo measurement efficiency for the variability of human subjects and interspecies scaling of organ doses will succeed.

  20. A new technique for dosimetry reaction cross-section evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Badikov, S.A. [JSC Energy and Industry Analytica, 127287, Moscow (Russian Federation)

    2011-07-01

    Document available in abstract form only, full text of document follows: An objective of this paper is a unification of the procedure for dosimetry reaction cross-section evaluation. A set of requirements for the unified evaluation procedure is presented. A new code (ORTHO) was developed in order to meet these requirements. A statistical model, an algorithm, and the basic formulae employed in the code are described. The code was used for Ti48(n,p) reaction cross-section evaluation. The results of the evaluation are compared to International Reactor Dosimetry File (IRDF)-2002 data. The evaluated cross-sections and their correlations from this work are in good agreement with the IRDF-2002 evaluated data, whereas the uncertainties of the evaluated cross-sections are inconsistent. (authors)

  1. Development of CVD diamond detectors for clinical dosimetry

    Science.gov (United States)

    Piliero, M. A.; Hugtenburg, R. P.; Ryde, S. J. S.; Oliver, K.

    2014-11-01

    The use of chemical vapour deposition (CVD) methods for the manufacture of diamonds could lead to detectors for high-resolution radiotherapy dosimetry that are cheaper and more reproducible than detectors based on natural diamonds. In this work two prototype designs (Diamond Detectors Ltd, Poole) of CVD diamond detectors were considered. The detectors were encapsulated in a water-proof housing in a form-factor that would be suitable for dosimetry measurements in water, as well as solid material phantoms. Stability of the dosimeter over time, the dose-response, dose-rate response and angular-response were examined. The study demonstrated that the detector behaviour conformed with theory in terms of the dose-rate response and had acceptable properties for use in the clinic.

  2. High-dose dosimetry using natural silicate minerals

    Energy Technology Data Exchange (ETDEWEB)

    Carmo, Lucas S. do; Mendes, Leticia, E-mail: isatiro@usp.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Watanabe, Shigueo; Rao, Gundu; Lucas, Natasha; Sato, Karina, E-mail: lacifid@if.usp.br [Universidade de Sao Paulo (USP), Sao Paulo, SP (Brazil). Instituto de Fisica. Departamento de Fisica Nuclear; Barbosa, Renata F., E-mail: profcelta@hotmail.com [Universidade Federal de Sao Paulo (UNIFESP), Santos, SP (Brazil). Departamento de Ciencias do Mar

    2015-07-01

    In the present study, certain natural silicate minerals such as aquamarine (AB), morganite (PB), goshenite (WB), white jadeite (JW), green jadeite (JG), pink tourmaline (PT) and two varieties of jadeite-like quartz, denoted here by JQ1 and JQ2, were investigated using the thermoluminescence technique to evaluate their potential for use as very-high- and high-dose dosimeters. These minerals respond to high doses of γ-rays of up to 1000 kGy and often to very high doses of up to 3000 kGy. The TL response of these minerals may be considered to be satisfactory for applications in high-dose dosimetry. Investigations of electron paramagnetic resonance and optically stimulated luminescence dosimetry are in progress. (author)

  3. Dosimetry of {beta} extensive sources; Dosimetria de fuentes {beta} extensas

    Energy Technology Data Exchange (ETDEWEB)

    Rojas C, E.L.; Lallena R, A.M. [Departamento de Fisica Moderna, Universidad de Granada, E-18071 Granada (Spain)

    2002-07-01

    In this work, we have been studied, making use of the Penelope Monte Carlo simulation code, the dosimetry of {beta} extensive sources in situations of spherical geometry including interfaces. These configurations are of interest in the treatment of the called cranealfaringyomes of some synovia leisure of knee and other problems of interest in medical physics. Therefore, its application can be extended toward problems of another areas with similar geometric situation and beta sources. (Author)

  4. Feasibility of portal dosimetry for flattening filter-free radiotherapy.

    Science.gov (United States)

    Chuter, Robert W; Rixham, Philip A; Weston, Steve J; Cosgrove, Vivian P

    2016-01-08

    The feasibility of using portal dosimetry (PD) to verify 6 MV flattening filter-free (FFF) IMRT treatments was investigated. An Elekta Synergy linear accelerator with an Agility collimator capable of delivering FFF beams and a standard iViewGT amorphous silicon (aSi) EPID panel (RID 1640 AL5P) at a fixed SSD of 160 cm were used. Dose rates for FFF beams are up to four times higher than for conventional flattened beams, meaning images taken at maximum FFF dose rate can saturate the EPID. A dose rate of 800 MU/min was found not to saturate the EPID for open fields. This dose rate was subsequently used to characterize the EPID for FFF portal dosimetry. A range of open and phantom fields were measured with both an ion chamber and the EPID, to allow comparison between the two. The measured data were then used to create a model within The Nederlands Kanker Instituut's (NKI's) portal dosimetry software. The model was verified using simple square fields with a range of field sizes and phantom thicknesses. These were compared to calculations performed with the Monaco treatment planning system (TPS) and isocentric ion chamber measurements. It was found that the results for the FFF verification were similar to those for flattened beams with testing on square fields, indicating a difference in dose between the TPS and portal dosimetry of approximately 1%. Two FFF IMRT plans (prostate and lung SABR) were delivered to a homogeneous phantom and showed an overall dose difference at isocenter of ~0.5% and good agreement between the TPS and PD dose distributions. The feasibility of using the NKI software without any modifications for high-dose-rate FFF beams and using a standard EPID detector has been investigated and some initial limitations highlighted.

  5. Report on the Personnel Dosimetry at AB Atomenergi during 1965

    Energy Technology Data Exchange (ETDEWEB)

    Edvardsson, K.A.

    1966-10-15

    This report presents the results of the personnel dosimetry at AB Atomenergi during 1965. No doses exceeding the recommendations of ICRP were reported. For AB Atomenergi the average external total body dose during the year was 60 mrem which corresponds to 89.4 manrem. 31200 gamma films and 5850 neutron films were evaluated. 2067 urine analyses and 692 measurements of body activity were made.

  6. JENDL dosimetry file 99 (JENDL/D-99)

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Katsuhei [Kyoto Univ., Kumatori, Osaka (Japan). Research Reactor Institute; Iguchi, Tetsuo [Nagoya Univ., Faculty of Engineering, Nagoya, Aichi (Japan); Iwasaki, Shin [Tohoku Univ., Faculty of Engineering, Sendai, Miyagi (JP)] [and others

    2002-01-01

    The JENDL Dosimetry File 99 (JENDL/D-99), which is a revised version of the JENDL Dosimetry File 91 (JENDL/D-91), has been compiled and released for the determination of neutron flux and energy spectra. This work was undertaken to remove the inconsistency between the cross sections and their covariances in JENDL/D-91 since the covariances were mainly taken from IRDF-85 although the cross sections were based on JENDL-3. Dosimetry cross sections have been evaluated for 67 reactions on 47 nuclides together with covariances. The cross sections for 34 major reactions and their covariances were simultaneously generated, and the remaining 33 reaction data were mainly taken from JENDL/D-91. Latest measurements were taken into account in the evaluation. The resultant evaluated data are given in the neutron energy region below 20 MeV in both of point-wise and group-wise files in the ENDF-6 format. In order to confirm the reliability of the evaluated data, several integral tests have been carried out: comparisons with average cross sections measured in fission neutron fields, fast/thermal reactor spectra, DT neutron fields and Li(d,n) neutron fields. It was found from the comparisons that the cross sections calculated from JENDL/D-99 are generally in good agreement with the measured data. The contents of JENDL/D-99 and the results of the integral tests are described in this report. All of the dosimetry cross sections are shown in a graphical form in the Appendix. (author)

  7. Monte Carlo physical dosimetry for small photon beams

    Energy Technology Data Exchange (ETDEWEB)

    Perucha, M.; Rincon, M.; Leal, A.; Carrasco, E. [Sevilla Univ. (Spain). Dept. Fisiologia Medica y Biofisica; Sanchez-Doblado, F. [Sevilla Univ. (Spain). Dept. Fisiologia Medica y Biofisica]|[Hospital Univ. Virgen Macarena, Sevilla (Spain). Servicio de Oncologia Radioterapica; Nunez, L. [Clinica Puerta de Hierro, Madrid (Spain). Servicio de Radiofisica; Arrans, R.; Sanchez-Calzado, J.A.; Errazquin, L. [Hospital Univ. Virgen Macarena, Sevilla (Spain). Servicio de Oncologia Radioterapica

    2001-07-01

    Small field dosimetry is complicated due to the lack of electronic equilibrium and to the high steep dose gradients. This works compares PDD curves, profiles and output factors measured with conventional detectors (film, diode, TLD and ionisation chamber) and calculated with Monte Carlo. The 6 MV nominal energy from a Philips SL-18 linac has been simulated by using the OMEGA code. MC calculation reveals itself as a convenient method to validate OF and profiles in special conditions, such as small fields. (orig.)

  8. Monte Carlo simulations to replace film dosimetry in IMRT verification

    OpenAIRE

    Goetzfried, Thomas; Rickhey, Mark; Treutwein, Marius; Koelbl, Oliver; Bogner, Ludwig

    2011-01-01

    Patient-specific verification of intensity-modulated radiation therapy (IMRT) plans can be done by dosimetric measurements or by independent dose or monitor unit calculations. The aim of this study was the clinical evaluation of IMRT verification based on a fast Monte Carlo (MC) program with regard to possible benefits compared to commonly used film dosimetry. 25 head-and-neck IMRT plans were recalculated by a pencil beam based treatment planning system (TPS) using an appropriate quality assu...

  9. Luminescence dosimetry: recent developments in theory and applications

    Energy Technology Data Exchange (ETDEWEB)

    McKeever, S.W.S. [Department of Physics, Oklahoma State University, Stillwater, OK 74078-3072 (United States)

    2000-07-01

    Thermally and optically stimulated luminescence have been used in applications in solid state physics, radiation dosimetry and geological dating for several decades. This paper gives a generalized description of these methods in terms of non-equilibrium thermodynamics and in doing so highlights similarities and differences between the methods. Recent advances in both the theory and application of the techniques are highlighted with numerous specific examples. (Author)

  10. Padrões Contábeis internacionais do IASB: Um estudo comparativo com as normas contábeis brasileiras e sua aplicação

    Directory of Open Access Journals (Sweden)

    L. Nelson Carvalho

    2009-10-01

    Full Text Available Atribui-se a Jonh Kennteh Galbraith a afirmativa de que os economistas deveriam se preocupar em medir "Felicidade Nacional Bruta" do que "Produto Nacional Bruto" e que "Felicidade", objetivamente considerada , é o pai da família ou jovem em idade de trabalho a encontratem emprego e oportunidades. Isso se dá, em grande parte, por um setor empresarial empreendedor, e este mostra sua vitalidade por meio de mecanismos de comunicação que espelhem suas virtudes. O melhor, o mais clássico e universal - conquanto não é o único- mecanismo de comunicação de desempenho empresarial com credores , investidores, governo, fornecedores é o conjunto das demonstrações contábeis.

  11. In Vitro Exposure Systems and Dosimetry Assessment Tools ...

    Science.gov (United States)

    In 2009, the passing of The Family Smoking Prevention and Tobacco Control Act facilitated the establishment of the FDA Center for Tobacco Products (CTP) and gave it regulatory authority over the marketing, manufacture and distribution of tobacco products, including those termed “modified risk”. On 4-6 April 2016, the Institute for In Vitro Sciences, Inc. (IIVS) convened a workshop conference titled “In Vitro Exposure Systems and Dosimetry Assessment Tools for Inhaled Tobacco Products” to bring together stakeholders representing regulatory agencies, academia, and industry to address the research priorities articulated by the FDA CTP. Specific topics were covered to assess the status of current in vitro smoke and aerosol/vapor exposure systems, as well as the various approaches and challenges to quantifying the complex exposures, in in vitro pulmonary models developed for evaluating adverse pulmonary events resulting from tobacco product exposures. The four core topics covered were, 1) Tobacco Smoke And E-Cigarette Aerosols, 2) Air-Liquid Interface-In Vitro Exposure Systems, 3) Dosimetry Approaches For Particles And Vapors; In Vitro Dosimetry Determinations and 4) Exposure Microenvironment/Physiology Of Cells. The two and a half day workshop included presentations from 20 expert speakers, poster sessions, networking discussions, and breakout sessions which identified key findings and provided recommendations to advance these technologies. Here, we will re

  12. Advanced Corneal Cross-Linking System with Fluorescence Dosimetry

    Directory of Open Access Journals (Sweden)

    Marc D. Friedman

    2012-01-01

    Full Text Available Purpose. This paper describes an advanced system that combines corneal cross-linking with riboflavin with fluorescence dosimetry, the ability to measure riboflavin diffusion within the cornea both before and during UVA treatment. Methods and Results. A corneal cross-linking system utilizing a digital micromirror device (DMD was assembled and used to measure diffusion coefficients of 0.1% riboflavin in 20% dextran in porcine eyes. A value of (3.3±0.2×10−7 cm2/s was obtained for the stroma. Diffusion coefficients for the transepithelial formulation of 0.1% riboflavin in 0.44% saline and 0.02% BAK were also measured to be 4.7±0.3×10−8 cm2/s for epithelium only and (4.6±0.4×10−7 cm2/s for stroma only. Riboflavin consumption during a UVA treatment was also demonstrated. Conclusion. A new advanced corneal cross-linking system with fluorescence dosimetry of riboflavin has been demonstrated. It is hoped that this method may play a significant role in determining the underlying mechanisms of corneal cross-linking and assist with the development of additional riboflavin formulations. Moreover, dosimetry may prove valuable in providing a method to account for the biological differences between individuals, potentially informing cornea-specific UVA treatment doses in real time.

  13. Characterisation of OSL and OSLN droplets for dosimetry.

    Science.gov (United States)

    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.

  14. The Chernobyl experience in the area of retrospective dosimetry.

    Science.gov (United States)

    Chumak, Vadim V

    2012-03-01

    The Chernobyl accident, which occurred on 26 April 1986 at a nuclear power plant located less than 150 km north of Kiev, was the largest nuclear accident to date. The unprecedented scale of the accident was determined not only by the amount of released activity, but also by the number of workers and of the general public involved, and therefore exposed to increased doses of ionising radiation. Due to the unexpected and large scale of the accident, dosimetry techniques and practices were far from the optimum; personal dosimetry of cleanup workers (liquidators) was not complete, and there were no direct measurements of the exposures of members of the public. As a result, an acute need for retrospective dose assessment was dictated by radiation protection and research considerations. In response, substantial efforts have been made to reconstruct doses for the main exposed cohorts, using a broad variety of newly developed methods: analytical, biological and physical (electron paramagnetic resonance spectroscopy of teeth, thermoluminescence of quartz) and modelling. This paper reviews the extensive experience gained by the National Research Center for Radiation Medicine, Academy of Medical Sciences, Ukraine in the field of retrospective dosimetry of large cohorts of exposed population and professionals. These dose reconstruction projects were implemented, in particular, in the framework of epidemiological studies, designed to follow-up the medical consequences of the Chernobyl accident and study health effects of ionizing radiation, particularly Ukrainian-American studies of cataracts and leukaemia among liquidators.

  15. Proceedings of the second conference on radiation protection and dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Swaja, R. E.; Sims, C. S. [eds.

    1988-11-01

    The Second Conference on Radiation Protection and Dosimetry was held during October 31--November 3, 1988, at the Holiday Inn, Crowne Plaza Hotel in Orlando, Florida. This meeting was designed with the objectives of promoting communication among applied, research, regulatory, and standards personnel involved in radiation protection and providing them with sufficient information to evaluate their programs. To facilitate meeting these objectives, a technical program consisting of more than 75 invited and contributed oral presentations encompassing all aspects of radiation protection was prepared. General topics considered in the technical sessions included external dosimetry, internal dosimetry, calibration, standards and regulations, instrumentation, accreditation and test programs, research advances, and applied program experience. In addition, special sessions were held to afford attendees the opportunity to make short presentations of recent work or to discuss topics of general interest. This document provides a summary of the conference technical program and a partial collection of full papers for the oral presentations in order of delivery. Individual papers were processed separately for the data base.

  16. Dosimetry with phantom for total body irradiation (TBI)

    Energy Technology Data Exchange (ETDEWEB)

    Tezuka, Takako; Sakakura, Noriyuki; Obata, Yasunori; Tabushi, Katuyoshi; Kondou, Satoru [Nagoya Univ. (Japan). School of Health Sciences; Koyama, Syuuji; Aoyama, Yuuichi; Shimohira, Akiyo [Nagoya Univ. (Japan). Hospital

    2002-04-01

    Total body irradiation (TBI) is being used as a method of preparation for bone marrow transplantation (BMT). In TBI, the dose calculation is based on dosimetry using a phantom. We measured the basic dose with a phantom using a 10 MV X-rays. We confirmed the accuracy of the dose calculation performed in our facilities and investigated a method of more accurate dosimetry. We measured the variation in dose according to the size of the phantom and the depth using a tough water phantom, and examined the difference in TMR according to SCD, field size, and size of the phantom. Consequently, the dose has been changed regardless of the size of the phantom at larger than 80 x 30 x 30 cm{sup 3}, and it is about 1% larger than 30 x 30 x 30 cm{sup 3}. Also TMR has changed according to various conditions, including the size of the phantom, field size, and SCD. Therefore, it was found that dosimetry using the 30 x 30 x 30 cm{sup 3} phantom leads to underestimation in dose calculation, and there is no difference in dose between the field size of 151.5 x 160 cm{sup 2} and 151.5 x 80 cm{sup 2}. It is also necessary to consider the effect of the vertical size of the phantom. (author)

  17. Dosimetry using radiosensitive gels in radiotherapy: significance and methods; Dosimetrie par gels radiosensibles en radiotherapie. Interet et methodes

    Energy Technology Data Exchange (ETDEWEB)

    Gibon, D. [Dept. de Radiotherapie, Centre Oscar Lambret, Lille Cedex (France); Bourel, P. [Lab. de Biophysique, Inst. de Technologie Medicale, Centre Hospitalier Universitaire, Lille (France); Castelain, B. [Dept. de Radiotherapie, Centre Oscar Lambret, Lille Cedex (France); Marchandise, X.; Rousseau, J. [Lab. de Biophysique, Inst. de Technologie Medicale, Centre Hospitalier Universitaire, Lille (France)

    2001-02-01

    The goal of conformal radiotherapy is to concentrate the dose in a well-defined volume by avoiding the neighbouring healthy structures. This technique requires powerful treatment planning software and a rigorous control of estimated dosimetry. The usual dosimetric tools are not adapted to visualize and validate complex 3D treatment. Dosimetry by radiosensitive gel permits visualization and measurement of the three-dimensional dose distribution. The objective of this work is to report on current work in this field and, based on our results and our experience, to draw prospects for an optimal use of this technique. Further developments will relate to the realization of new radiosensitive gels satisfying, as well as possible, cost requirements, easy realization and use, magnetic resonance imagery (MRI) sensitivity, tissue equivalence, and stability. Other developments focus on scanning methods, especially in MRI to measure T1 and T2. (author)

  18. Enhanced biological phosphorus removal - results of a full scale pilot plant; Erhoehte biologische Phosphatelimination - Betriebsergebnisse einer grosstechnischen Versuchsanlage

    Energy Technology Data Exchange (ETDEWEB)

    Wolf, P. [Kassel Univ. (Gesamthochschule) (Germany). Fachbereich 14 - Siedlungswasserwirtschaft; Bendzuck, C. [Kassel Univ. (Gesamthochschule) (Germany). Fachbereich 14 - Siedlungswasserwirtschaft

    1996-01-01

    Within a research project one line of Kassel`s wastewater treatment plant has been rebuilt to a large scale pilot plant run with the MUCT process configuration. Different investigations with variation of inflow size, trend of inflow over time and wastewater temperature have been done. The relation between the efficiency of enhanced biological phosphorus removal (EBPR) and the hydraulic loading is shown in some examples. Over all, the EBPR increases with the wastewater temperature, with the available organic carbon in the inflow and with decreasing fluctuation in the trend of inflow over time. (orig.) [Deutsch] Im Rahmen eines Forschungsvorhabens wurde ein Teil der biologischen Stufe der Kasseler Klaeranlage zur erhoehten biologischen Phosphatelimination nach dem MUCT-Verfahren umgebaut. Es wurden Versuche bei konstanter und periodisch schwankender hydraulischer Belastung sowie bei unterschiedlichen Abwassertemperaturen durchgefuehrt. Untersucht wurde die Abhaengigkeit der biologischen Phosphatelimination von verschiedenen Belastungssituationen und die Phosphorumsaetze innerhalb der Belebung sowohl in zeitlicher als auch in oertlicher Abhaengigkeit. Die Wiederholung bestimmter Versuchsphasen bei verschiedenen Abwassertemperaturen liess Rueckschluesse auf die Temperaturabhaengigkeit der biologischen Phosphatelimination zu. Der Wirkungsgrad der biologischen Phosphatelimination steigt mit der Temperatur, dem Angebot an organischem Kohlenstoff in der anaeroben Zone und mit zunehmender Vergleichmaessigung der hydraulischen Belastung. (orig.)

  19. Metrological aspects of the dosimetry in X-ray diagnostics; Metrologische Aspekte der Dosimetrie in der Roentgendiagnostik

    Energy Technology Data Exchange (ETDEWEB)

    Bueermann, Ludwig [Physikalisch-Technische Bundesanstalt (PTB), Braunschweig (Germany). Arbeitsgruppe ' Dosimetrie fuer die Roentgendiagnostik'

    2013-06-15

    The author describes the evaluation methods in dosimetry with special regards to the air kerma. Furthermore application-specific quantities in radiography, mammography, and computer tomography are described. Then quality assurance in X-ray diagnostics and the determination of the organ dosis and the effective patient dosis are described. Finally the requirements on the uncertainties of dose measurements in X-ray diagnostics are considered. (HSI)

  20. Estimativas contábeis e qualidade do lucro: análise setorial no Brasil

    Directory of Open Access Journals (Sweden)

    Paulo Roberto Barbosa Lustosa

    2010-08-01

    Full Text Available Diversos estudos vêm sendo realizados no exterior e mais recentemente, no Brasil, no sentido de se compreender melhor o comportamento e as relações existentes entre accruals, lucro líquido, fluxos de caixa e a qualidade dos lucros contábeis. Devido a sua utilidade para os mais diversos fins, o lucro e sua qualidade como parâmetro de mensuração de desempenho têm recebido cada vez mais atenção por parte dos usuários das informações contábeis. Assim, o presente estudo tem como finalidade analisar os accruals, como proxy para a qualidade do lucro, dos diversos setores da economia brasileira e verificar o impacto causado pelos accruals setoriais na percepção do mercado. Para tanto, foram formuladas e testadas, por meio de estudo empírico-análitico, duas hipóteses de pesquisas. A amostra foi constituída de séries históricas de variáveis contábeis e preços das ações, no período de 2003 a 2006, de 133 empresas listadas na Bovespa, de oito setores. Os resultados obtidos mostram que os níveis de accruals são diferentes para alguns setores da economia brasileira e que o mercado reage negativamente às variações nos níveis de accruals para a maior parte dos setores analisados. Contudo, não foi encontrada significância estatística nessa relação.