Twenty-year follow-up of a Pu/Am inhalation case

In 1983 a technician inhaled a mixture of Pu/Am aerosols in an accidental situation in the hotlab of Paul Scherrer Institute (PSI). This case is of interest for long-term follow-up since the technician was relatively young (26 y) at the time of intake, no chelating agent was used to alter retention and excretion and the inhaled activity was rather high (≈20 kBq of alpha emitters). The results obtained from periodic lung counts, urinary and faecal excretions as well as from some bone and liver measurements up to the year 2003 are presented. The measurements were mainly made at PSI but also at FZK Karlsruhe, Germany, and PNNL Hanford, USA. The evaluation and dose estimation of this case was done by several institutions, such as FZK, PNNL and NRPB in addition to PSI. Elements of the case were used in international biokinetic model validation programs by EURADOS/EULEP and IAEA and the 241Am data are given as example in Annex E of the ICRP ‘Guide for the Practical Application of the ICRP Human Respiratory Tract Model'. An overview is given on the various results obtained by the different institutions using their models and methods for interpretation of the measured data. While estimation of intake varies by more than an order of magnitude, final estimation of effective committed dose varies only in the range of 0.5-1.5 S

Low temperature transport on surface conducting diamond

Magneto-transport measurements were performed on surface conducting hydrogen-terminated diamond (100) hall bars at temperatures between 0.1-5 K in magnetic fields up to 8T.Comment: 2 pages Optoelectronic and Microelectronic Materials & Devices (COMMAD), 2012 Conferenc

30-y follow-up of a Pu/Am inhalation case

In 1983, a young man inhaled accidentally a large amount of plutonium and americium. This case was carefully followed until 2013. Since no decorporation measures had been taken, the undisturbed metabolism of Pu and Am can be derived from the data. First objective was to determine the amount of inhaled radionuclides and to estimate committed effective dose. In vivo and excretion measurements started immediately after the inhalation, and for quality assurance, all types of measurements were performed by different labs in Europe and the USA. After dose assessment by various international groups were completed, the measurements were continued to produce scientific data for model validation. The data have been analysed here to estimate lung absorption parameter values for the inhaled plutonium and americium oxide using the proposed new ICRP Human Respiratory Tract Model. As supplement to the biokinetic modelling, biological data from three different cytogenetic markers have been added. The estimated committed effective dose is in the order of 1 Sv. The subject is 30 y after the inhalation, of good health, according to a recent medical check-u

Linking of flow field, bed geometry and fish trajectories on unstructured block ramps

Naturnahe unstrukturierte Sohlengleiten kommen als naturbasierte Wasserbauwerke bei der Herstellung der ökologischen Durchgängigkeit und Revitalisierung von Fließgewässern zum Einsatz. Da eine universelle Beschreibung des Strömungsfeldes über rauen Sohlen bisher nicht möglich ist, muss auf empirische Berechnungsansätze zurückgegriffen werden, so dass bei der hydraulischen Dimensionierung lediglich Mittelwerte der für den Fischaufstieg relevanten Größen Wassertiefe und Fließgeschwindigkeit angesetzt werden können. Dies bedeutet wiederum, dass ein Nachweis passierbarer Wanderkorridore für aufsteigende Fische nicht möglich ist. Um grundsätzliche Aussagen über die Fischbewegungen auf naturnahen unstrukturierten Sohlengleiten zu erhalten, wurden im Rahmen dieser Arbeit erstmals kombinierte fischökologische und hydraulische Untersuchungen an einer geeigneten Sohlengleite im Feld sowie an einem unskalierten Modell des Bauwerks in Laborexperimenten durchgeführt. Ziel der Untersuchungen war es, die Schwimmpfade von Fischen mit dem lokalen Strömungsfeld und der Sohlengeometrie zu verknüpfen. Eine bestehende Sohlengleite in der Ilme in Südniedersachsen wurde dafür als best-practice-Beispiel ausgewählt und detailliert vermessen. Der daraus erhaltene digitale Zwilling diente als Basis für die Herstellung des unskalierten Labormodells der für den Fischaufstieg relevanten Bereiche der Sohlengleite. Umfangreiche Laboruntersuchungen fanden unter kontrollierten Bedingungen im Laxeleratorn im Vattenfall-Wasserbaulabor in Älvkarleby, Schweden, statt. Kamerabasierte Fischbeobachtungen sowie hydraulische Messungen wurden unter verschiedenen Randbedingungen durchgeführt. Auf Grundlage der Erfahrungen in den Laboruntersuchungen konnte das Versuchsprogramm schließlich in Felduntersuchungen an der Ilme wiederholt und der Datensatz vervollständigt werden. Sowohl Fischtrajektorien verschiedener Arten und Größen- bzw. Leistungsklassen als auch lokale und globale Strömungsbedingungen wurden im Labor wie in der Natur in Abhängigkeit des Abflusses und der Sohlentopgraphie dokumentiert, was wiederum die Identifizierung und Quantifizierung von Wanderkorridoren von aufsteigenden Fischen ermöglichte. Die Arbeit erlaubt erstmals einen direkten Vergleich von Labor- und Naturuntersuchungen auf einer naturnahen Sohlengleite. Die Ergebnisse zeigen, dass es grundsätzlich möglich ist, großskalige Strukturen wie die hier betrachtete Sohlengleite in ethohydraulischen Experimenten einzusetzen, da die Schwimmpfade bei beiden Umgebungen in ähnlichen Bereichen verlaufen, was wiederum die Qualität der Laborergebnisse bestätigt. Ebenso wird deutlich, dass insbesondere die Fließgeschwindigkeiten sowie die Turbulenz der Strömung bei der Bewertung der Passierbarkeit eine größere Rolle spielen als die Wassertiefen. Die reine Berücksichtigung von integraler bzw. mittlerer Geschwindigkeiten im Prozess der Dimensionierung ist zumindest kritisch zu sehen.Nature-like unstructured block ramps are used as nature-based hydraulic structures to establish the ecological continuity and revitalization of river systems. As a universal description of the flow field over rough beds is not yet possible, empirical approaches must be used, so that only mean values of the water depth and flow velocity relevant for fish migration can be used for hydraulic design. This in turn means that it is not possible to provide evidence of passable migration corridors for ascending fish. In order to obtain basic information on fish movements on nature-like unstructured block ramps, this work was the first to carry out combined fish ecological and hydraulic investigations on a suitable ramp structure in the field and on a full-scale model of the structure in laboratory experiments. The aim of the investigations was to link the swimming paths of different fish species and performance classes with the local flow field and the bed geometry. An existing block ramp in the river Ilme in southern Lower Saxony (Germany) was chosen as a best-practice example and measured by a detailed survey . The resulting digital twin served as the basis for the production of a full-scale laboratory model of the ramp areas relevant for fish migration. Extensive laboratory tests were carried out under controlled conditions in the Laxeleratorn at the Vattenfall hydraulic engineering laboratory in Älvkarleby, Sweden. Camera-based fish observations and hydraulic measurements were performed under various boundary conditions. Based on the experience gained in the laboratory studies, the experimental program was repeated in field observations and measurements on the Ilme. Both fish trajectories of different species and size classes as well as local and global flow conditions were documented in the laboratory and in the field as a function of discharge and bed topography, which in turn enabled the identification and quantification of migration corridors of ascending fish. For the first time, this work allows a direct comparison of laboratory and field investigations on a nature-like unstructured block ramp. The results show that it is fundamentally possible to use large-scale structures such as the block ramp considered here in ethohydraulic experiments, as the swimming paths in both environments run in similar ranges, which in turn confirms the quality of the laboratory results. It is also clear that the flow velocities and the turbulence of the current play a greater role in the assessment of passability than the water depths. The mere consideration of integral or mean velocities in the dimensioning process must be viewed critically

An excess Ra-226 chronology for deep-sea sediments from Saanich Inlet, British Columbia

To further explore the efficacy of 226Ra(excess) dating for deep-sea sediments, previously dated varve sediments from Saanich Inlet were investigated. Ages obtained using 226Ra(excess) are comparable to the varve ages in the upper 20-25 m of the sedimentary record, but radiometric ages for those sediments older than c. 4000 yr BP are significant underestimates. This results from major changes in sedimentation within Saanich Inlet around 4000 yr BP linked to rising sea levels, with younger sediments characterised by a higher biogenic contribution resulting from the establishment of an anoxic fjord environment. The older sediments were deposited in a shallow water inlet characterised by variable Ra mass balance and non-radiogenic losses. Therefore, while 226Ra(excess) can produce reliable dates, its application may be limited where the relative significance of authigenic and allogenic input and bottom water anoxia have been variable and where closed-system behaviour is compromised

Innovationsmanagement in der IT Beratung und Systemintegration

In der Dienstleistungsdomäne der IT-Beratung und Systemintegration wird das Innovationsmanagement nur unzureichend zur Sicherung zukünftiger Erfolgspotenziale eingesetzt. Mit meiner interpretativ-kritischen Forschungsarbeit möchte ich den aktuellen Stand zu diesem Thema auf Grundlage meines ethnographischen Hintergrunds sowie ausgewählter qualitativer Fallstudien aufzeigen. Ziel meiner Forschung ist, diesen Status Quo überwinden zu helfen. Im Rahmen von Aktionsforschung habe ich bei einem IT-Dienstleister einen Ansatz des Innovationsmanagements für ein Unternehmen der IT-Beratung und der Systemintegration entwickelt. Ein deduktiv hergeleitetes Domänenmodell hilft mir die Grundlagen zu Innovation und Innovationsmanagement spezifisch für die IT-Beratung und Systemintegration zu definieren. Ich zeige, dass die Industrie vornehmlich ein am Technologie- und Produkteinsatz orientiertes Innovationsmanagement ("Technology-Push") einsetzt und leiste einen Beitrag zum Verständnis der Gestaltung und Wirkung des heute üblichen Innovationsmanagements in IT-Unternehmen. Aus meiner Sicht muss dieses mit einem am fachlichen Kundennutzen orientierten Innovationsmanagement ("Market-Pull") ergänzt werden, für das ich mögliche Managementinstrumente einführe. Abschließend schlage ich Wege zum erfolgreichen Zusammenspiel dieser beiden Formen des Innovationsmanagement vor und diskutiere die noch offenen Forschungsfragen

Examining Possible Challenges in the Recruitment and Retention of Female Police Officers in the Southeast Texas Region

Despite progress in other career fields, women remain underrepresented in law enforcement by a large margin, and recent numbers have been stable. Issues for women in law enforcement have been well researched; however, few recent studies have detailed female police officers’ personal experiences. The study problem concerned the challenges and barriers faced by women who choose law enforcement as a career and their underrepresentation. The purpose of this phenomenological study was to explore the lived experiences of female police officers, recruits, and applicants living in southeastern Texas and their perceptions of challenges and barriers for women in the field. Data were collected to understand women’s experiences using in-depth interviews and a qualitative questionnaire. The research questions concerned the participants’ perceptions of factors contributing to low representation, the barriers that they faced during the academy and hiring process, as officers, and while remaining in policing. The theoretical framework used to interpret results included labeling and conflict theories. A purposeful sample of seven full-time women police officers from three law enforcement agencies participated. The data analysis consisted of coding and theming, followed by describing the findings in a narrative form. Four themes emerged from the analysis: gender discrimination, sexual harassment and assault, family and personal factors, and leadership. The results may contribute to positive social change by raising awareness of women officers’ employment, discrimination and harassment concerns, and accomplishments in law enforcement. Additionally, findings may assist police administrators and legislators in creating policies and procedures that reflect awareness of female officers’ needs