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Many studies have estimated the social cost of carbon (SCC). We critically evaluate SCC estimates, focusing on omitted cost categories, discounting, uncertainties about damage costs and risk aversion. This allows for the calculation of a lower bound to the SCC. Dominant SCC values turn out to be gross underestimates, notably, but not only, for a low discount rate. The validity of this lower bound is supported by a precautionary approach to reflect risk aversion against extreme climate change. The results justify a more stringent climate policy than is suggested by most influential past studies.

Abstract: Climate change is projected to increase the frequency and severity of extreme weather events. As a consequence, economic losses caused by natural catastrophes could increase significantly. This will have considerable consequences for the insurance sector. On the one hand, increased risk from weather extremes requires assessing expected changes in damage and including adequate climate change projections in risk management. On the other hand, climate change can also bring new business opportunities for insurers. This paper gives an overview of the consequences of climate change for the insurance sector and discusses several strategies to cope with and adapt to increased risks. The particular focus is on the Dutch insurance sector, as the Netherlands is extremely vulnerable to climate change, especially with regard to extreme precipitation and flooding. Current risk sharing arrangements for weather risks are examined while potential new business opportunities, adaptation strategies, and public–private partnerships are identified.

No abstract.

Wetlands provide many important goods and services to human societies, and generate nonuse values as well. Wetlands are also very sensitive ecosystems that are subject to much stress from human activities. Reducing the stress on wetlands requires a spatial matching between physical planning, hydrological and ecological processes, and economic activities. Spatially integrated modelling and evaluation can support this. The present study has developed a triple layer model that integrates information and concepts from social and natural sciences to address the analysis and evaluation of land-use scenarios for a wetlands area in the Netherlands, the Vecht area. This is the floodplain of river Vecht, located in the centre of the Netherlands. The study has resulted in a set of linked spatial hydrological, ecological and economic models, formulated at the level of grids and polders. The main activities incorporated in the system of models are housing, infrastructure, agriculture, recreation and nature conservation. The formulation of alternative development scenarios is dominated by land use and land cover options that are consistent with the stimulation of agriculture, nature or recreation. Two aggregate performance indicators have been constructed from model output, namely net present value of changes and environmental quality. The spatial characteristics of these indicators are retained in a spatial evaluation that ranks scenarios.

Osteoporosis commonly is assessed by bone quantity, using bone mineral density (BMD) measurements from dual‐energy X‐ray absorptiometry (DXA). However, such a measure gives neither information about the integrity of the trabecular architecture nor about the mechanical properties of the constituting trabeculae. We investigated the feasibility of deriving the elastic modulus of the trabeculae (the tissue modulus) from computer simulation of mechanical testing by microfinite element analysis (μFEA) in combination with measurements of ultrasound speed of sound (SOS) and BMD measurements. This approach was tested on 15 postmortem bovine bone cubes. The apparent elastic modulus of the specimens was estimated from SOS measurements in combination with BMD. Then the trabecular morphology was reconstructed using microcomputed tomography (μCT). From the reconstruction a mesh for μFEA was derived, used to simulate mechanical testing. The tissue modulus was found by correlating the apparent moduli of the specimens as assessed by ultrasound with the ones as determined with μFEA. A mean tissue modulus of 4.5 GPa (SD, 0.69) was found. When adjusting the μFEA‐determined elastic moduli of the entire specimens with their calculated tissue modulus, an overall correlation of R2= 96% with ultrasound‐predicted values was obtained. We conclude that the apparent elastic stiffness characteristics as determined from ultrasound correlate linearly with those from μFEA. From both methods in combination, the elastic stiffness of the mineralized tissue can be determined as an estimator for mechanical tissue quality. This method can already be used for biopsy specimens, and potentially could be applicable in vivo as well, when clinical CT or magnetic resonance imaging (MRI) tools with adequate resolution reach the market. In this way, mechanical bone quality could be estimated more accurately in clinical practice.

Osteoporosis commonly is assessed by bone quantity, using bone mineral density (BMD) measurements from dual‐energy X‐ray absorptiometry (DXA). However, such a measure gives neither information about the integrity of the trabecular architecture nor about the mechanical properties of the constituting trabeculae. We investigated the feasibility of deriving the elastic modulus of the trabeculae (the tissue modulus) from computer simulation of mechanical testing by microfinite element analysis (μFEA) in combination with measurements of ultrasound speed of sound (SOS) and BMD measurements. This approach was tested on 15 postmortem bovine bone cubes. The apparent elastic modulus of the specimens was estimated from SOS measurements in combination with BMD. Then the trabecular morphology was reconstructed using microcomputed tomography (μCT). From the reconstruction a mesh for μFEA was derived, used to simulate mechanical testing. The tissue modulus was found by correlating the apparent moduli of the specimens as assessed by ultrasound with the ones as determined with μFEA. A mean tissue modulus of 4.5 GPa (SD, 0.69) was found. When adjusting the μFEA‐determined elastic moduli of the entire specimens with their calculated tissue modulus, an overall correlation of R2= 96% with ultrasound‐predicted values was obtained. We conclude that the apparent elastic stiffness characteristics as determined from ultrasound correlate linearly with those from μFEA. From both methods in combination, the elastic stiffness of the mineralized tissue can be determined as an estimator for mechanical tissue quality. This method can already be used for biopsy specimens, and potentially could be applicable in vivo as well, when clinical CT or magnetic resonance imaging (MRI) tools with adequate resolution reach the market. In this way, mechanical bone quality could be estimated more accurately in clinical practice.

Abstract: The leak-rate of Ar through seals of liquid sodium pumps for sodium-cooled fast reactors is measured by thermal neutron activation analysis of oil and air samples taken from the cooling and lubrication systems of the seals. A method to calculate the leak-rate through a triple seal from the increase of the Ar concentrations is given.

Summary 1 or 2 g doses of cefodizime i.m. were studied in 287 patients admitted to hospital with acute purulent exacerbations of chronic bronchitis, mostly associated withHaemophilus influenzae, Streptococcus pneumoniae orMoraxella catarrhalis. Pharmacokinetic studies in serum and sputum on the first treatment day yielded mean peak serum concentrations of 50 to 100 mg/l, with corresponding sputum concentrations of 1.4 and 2.7 mg/l, after the two respective doses. No great differences were found between the clinical and microbiological results in the various dosage groups, and no corresponding improvement was noted with the highest dosages studied. In general, infection was eliminated in 90 to 95% of patients at the end of treatment, and in approximately 70 to 80% after a follow-up week. Some infections associated with ß-lactamase producingM. catarrhalis persisted or relapsed after treatment. Unwanted drug effects were recorded in five patients, leading to discontinuation in two. It is concluded that a single daily intramuscular dose of 1 g cefodizime for seven days produces satisfactory results in most patients.

A case of symptomatic Actinobacillus actinomycetemcomitans bacteremia in a patient with an implanted pacemaker is presented. Attacks of fever occurred for at least 1 year. Oral examination revealed a mild form of periodontitis. A. actinomycetemcomitans was isolated from several oral sites. DNA fingerprinting of strains from the blood and the oral cavity showed identical profiles. This finding strongly suggests that the oral cavity was the primary source of A. actinomycetemcomitans bacteremia in this case. The patient was treated with the combination of metronidazole plus amoxicillin for 7 days, which resulted in a rapid cure and elimination of A. actinomycetemcomitans from the blood and the oral cavity.