Observations and modelling of the global distribution and long-term trend of atmospheric 14CO2

Global high-precision atmospheric Δ14CO2 records covering the last two decades are presented, and evaluated in terms of changing (radio)carbon sources and sinks, using the coarse-grid carbon cycle model GRACE. Dedicated simulations of global trends and interhemispheric differences with respect to atmospheric CO2 as well as δ13CO2 and Δ14CO2, are shown to be in good agreement with the available observations (1940–2008). While until the 1990s the decreasing trend of Δ14CO2 was governed by equilibration of the atmospheric bomb 14C perturbation with the oceans and terrestrial biosphere, the largest perturbation today are emissions of 14C-free fossil fuel CO2. This source presently depletes global atmospheric Δ14CO2 by 12–14‰ yr−1, which is partially compensated by 14CO2 release from the biosphere, industrial 14C emissions and natural 14C production. Fossil fuel emissions also drive the changing north–south gradient, showing lower Δ14C in the northern hemisphere only since 2002. The fossil fuel-induced north–south (and also troposphere–stratosphere) Δ14CO2 gradient today also drives the tropospheric Δ14CO2 seasonality through variations of air mass exchange between these atmospheric compartments. Neither the observed temporal trend nor the Δ14CO2 north–south gradient may constrain global fossil fuel CO2 emissions to better than 25%, due to large uncertainties in other components of the (radio)carbon cycle

Thermo-Katalytische Vergasung als neuartiges Verfahren zur vollstaendigen Beseitigung organischer Schad- und Reststoffe (Vorprojekt) Abschlussbericht

Available from TIB Hannover: F99B449 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEBundesministerium fuer Bildung, Wissenschaft, Forschung und Technologie, Bonn (Germany)DEGerman

Fachkräfte sichern: Wie Krankenhäuser sich für die Zukunft rüsten können

Für Kliniken wird es zunehmend schwieriger, sich in dem unübersichtlichen und hart umkämpften Mediziner-Markt klar zu positionieren. Aktives Personalmarketing liegt im Trend – der Fachkräftemangel ist zu einer konkreten Herausforderung für das Personalmanagement in Kliniken geworden. Kliniken müssen ihre Personalmarketingaktivitäten, um Ärzte zu gewinnen und zu binden, schon jetzt neu skizzieren und für ihre Human-Ressource-Abteilung die Strukturen moderner Unternehmensführung übernehmen. Die Kliniken werden sich zukünftig einem verschärften Wettbewerb um die „besten medizinischen Köpfe“ stellen müssen. Im Rahmen einer qualitativen Untersuchung wurden Repräsentanten von Krankenhäusern, regionalen Gesundheitsnetzwerken und Hochschulen zu den Auswirkungen des Fachkräftemangels, zu Stellenwert, Ansätzen sowie den internen und externen Strategien des Personalmarketings interviewt. Im Spannungsfeld der derzeitigen Rekrutierungsmaßnahmen und den internen begrenzten klinischen Möglichkeiten der langfristigen Beschäftigung von Medizinern und Sicherstellung der Patientenversorgung werden die Kliniken den Blick über den besagten Tellerrand vornehmen müssen – Pioniere sind gefragt

Dose-intensified stereotactic body radiotherapy for painful vertebral metastases : a randomized phase 3 trial

Abstract: BackgroundThe purpose of this randomised study was to determine whether dose-intensified stereotactic body radiotherapy (SBRT) for painful vertebral metastases results in increased rates of pain improvement compared with conventional external beam radiotherapy (cEBRT) (control) 6 months after treatment.MethodsThis randomized, controlled phase 3 trial was conducted between November 2016 and January 2023, when it was stopped early. Patients were eligible if they were aged 18 years or older; had one or two painful, stable, or potentially unstable vertebral metastases; and had a life expectancy of 1 year or longer according to the investigator's estimates. Patients received 48.5 grays (Gy) in 10 fractions (with epidural involvement) or 40 Gy in five fractions (without epidural involvement) in the SBRT group and 30 Gy in 10 fractions or 20 Gy in five fractions in the cEBRT group, respectively. The primary end point was an improvement in the pain score at the treated site by at least 2 points (on a visual analog scale from 0 to 10 points) at 6-month follow-up. Data were analyzed on an intention-to-treat and per-protocol basis.ResultsOf 214 patients who were screened for eligibility, 63 were randomized 1:1 between SBRT (33 patients with 36 metastases) and cEBRT (30 patients with 31 metastases). The median age of all patients was 66 years, and 40 patients were men (63.5%). In the intention-to-treat analysis, the 6-month proportion of patients who had metastases with pain reduction by 2 or more points was significantly higher in the SBRT group versus the control group (69.4% vs. 41.9%, respectively; two-sided p = .02). Changes in opioid medication intake relative to baseline were nonsignificant between the groups. No differences were observed in vertebral compression fracture or adverse event rates between the groups.ConclusionsDose-intensified SBRT improved pain score more effectively than cEBRT at 6 months. In this randomized clinical trial that included 63 patients with 67 painful vertebral metastases, the proportion of those who had metastases with pain improvement at 6-month follow-up was 69% in the stereotactic body radiotherapy group versus 42% in the conventional external beam radiotherapy group: a significant difference. Changes in opioid medication intake relative to baseline between the groups were not significant, and dose-intensified stereotactic body radiotherapy was not associated with increased risks of adverse events

Robust optimization for resource-constrained project scheduling with uncertain activity durations

The purpose of this paper is to propose models for project scheduling when there is considerable uncertainty in the activity durations, to the extent that the decision maker cannot with confidence associate probabilities with the possible scenarios. Our modeling techniques stem from robust optimization, which is a theoretical framework that enables the decision maker to produce solutions that will have a reasonably good objective value under any likely input data scenario. We develop and implement a scenario-relaxation algorithm and a scenario-relaxationbased heuristic. The first algorithm produces optimal solutions but requires excessive running times even for medium-sized instances; the second algorithm produces high-quality solutions for medium-sized instances and outperforms two benchmark heuristics