<I>Background:</I> The inhalation of aerosols during electrosurgery is part of daily surgical life. This study analyses the toxic and cancerogenic components of the aerosols.<BR/><I>Methods:</I> Electrocautery, harmonic scalpel and argon beaming were utilised in a pig model. The collected aerosols were analysed by gas chromatography coupled with mass spectrometry for acrylamide, aldehydes and ketones, volatile and semivolatile organic compounds, and polycyclic aromatic hydrocarbons.<BR/><I>Results:</I> Surgical plume of all instruments comprehends toxic components including e.g. acrylamide, acetaldehyde, formaldehyde, and benzene. Composition and toxicity varies from applied technique, energy, and processed tissue. High temperature induces more toxic aerosols. Offtake devices reduce toxic inhalations.<BR/><I>Conclusions:</I> Surgical smoke contains toxic, partly cancerogenic compounds. Concentrations estimated for daily routine are probably below relevant health risk. Nevertheless, the exposition to surgical "smog" should be minimised at any time using offtake devices. Further examinations during clinical practice are necessary.

Strong genetic change over short spatial scales is surprising among marine species with high dispersal potential. Concordant breaks among several species signals a role for geographic barriers to dispersal. Along the coast of California, such breaks have not been seen across the biogeographic barrier of Point Conception, but other potential geographic boundaries have been surveyed less often. We tested for strong-population structure in 11 species of <I>Sebastes</I> sampled across two regions containing potential dispersal barriers, and conducted a meta-analysis including four additional species. We show two strong breaks north of Monterey Bay, spanning an oceanographic gradient and an upwelling jet. Moderate genetic structure is just as common in the north as it is in the south, across the biogeographic break at Point Conception. Gene flow is generally higher among deep-water species, but these conclusions are confounded by phylogeny. Species in the subgenus <I>Sebastosomus</I> have higher structure than those in the subgenus <I>Pteropodus</I>, despite having larvae with longer pelagic phases. Differences in settlement behavior in the face of ocean currents might help explain these differences. Across similar species across the same coastal environment, we document a wide variety of patterns in gene flow, suggesting that interaction of individual species traits such as settlement behavior with environmental factors such as oceanography can strongly impact population structure.

In the present study, we aim at relating Forbes' remarkable paper on "The lake as a microcosm", published 125 years ago, to the present status of knowledge in our own research group. Hence, we relate the observations Forbes made to our own microcosm, Lake Krankesjön in southern Sweden, that has been intensively studied by several research groups for more than three decades. Specifically, we focus on the question: Have we made any significant progress or did Forbes and colleagues blaze the trail through the unknown wilderness and we are mainly paving that intellectual road? We conclude that lakes are more isolated than many other biomes, but have, indeed, many extensions, for example, input from the catchment, fishing and fish migration. We also conclude that irrespective of whether lakes should be viewed as microcosms or not, the paper by Forbes has been exceptionally influential and still is, especially since it touches upon almost all aspects of the lake ecosystem, from individual behaviour to food web interactions and environmental issues. Therefore, there is no doubt that even if 125 years have passed, Forbes' paper still is a source of inspiration and deserves to be read. Hence, although aquatic ecology has made considerable progress over the latest century, Forbes might be viewed as one of the major pioneers and visionary scientists of limnology.

Zusammenfassend kann gesagt werden, daß die Empfindlichkeit gegen CuSO₄ der meisten niedern Wassertiere bedeutend größer ist, als allgemein angenommen wurde. Wenn also die biologische Selbstreinigung eines Gewässers gewünscht wird, darf es nicht durch Vitriol verunreinigt werden.<br/> Das Gift wirkt unabhängig von ökologischen Faktoren. Beim Litoral, bei rheophilen und planktonischen Tieren gibt es empfindlichere und weniger empfindliche Arten. Die jungen Individuen sterben bei geringerer Dosis als die alten der gleichen Spezies. Unterschiede in der Empfindlichkeit und in der Schnelligkeit der Wirkung besonders der starken Lösungen, beruhen einzig auf Unterschieden in der Körperbedeckung. Je schneller das Gift das lebendige Plasma durch Osmose erreichen kann, um so schneller tritt der Tod ein. Histologische Untersuchungen konnten noch nicht unternommen werden.

The evolutionary process of interspecific hybridization in cladocerans is reviewed based on ecological and population genetic data. The evolutionary consequences of hybridization, biogeographic patterns and fitness comparisons are analyzed within the conceptual framework of theories on hybridization. Among species of the <I>D. longispina</I> complex no interpopulational transition zones (hybrid zones) have been detected, but rather patchy distributions of hybrids and parentals have been found. Hybrids occur across broad geographic ranges and can be more abundant than parental species. Due to asexual reproduction (ameiotic parthenogenesis), hybrid breakdown can be avoided, and hybrids can even (temporarily) combine advantageous traits of both parental species. Evolutionary consequences may arise from repeated backcrossing, which in some cases results in introgression and patterns of reticulate evolution.

The biotransformation of toluene, benzene and naphthalene was examined in anaerobic sediment columns. Five columns filled with a mixture of sediments were operated in the presence of bicarbonate, sulfate, iron, manganese, or nitrate as electron acceptor. The columns were continuously percolated with a mixture of the three organic compounds (individual concentrations 25–200 μM) at 20°C.<br/> Toluene was transformed readily (within 1 to 2 months) under all redox conditions tested. Benzene was recalcitrant over the test period of 375–525 days in all five columns. Naphthalene was partly transformed in the column with nitrate or manganese as electron acceptor present; the addition of benzoate had a positive effect in the column with nitrate. In the column with sulfate, the majority of the added naphthalene disappeared. No effect was observed after adding and omitting an easier degradable substrate. [¹⁴C]naphthalene was used to confirm this disappearance to be the result of degradation; two third of the naphthalene was converted to CO₂.

During one year, concentration profiles of sulfate and methane were measured in sediment cores of eutrophic Lake Loosdrecht. Sulfate concentrations decreased exponentially with depth towards a constant threshold value of 7.6 ± 6.1 μM. Concentration profiles were used to calculate fluxes of sulfate and methane and to estimate the anaerobic mineralization rate. Anaerobic mineralization was highest in autumn which was probably due to an increased sedimentation of easily degradable organic carbon. At high rates (>600 μ mol organic carbon.m^-2.h^-1), sulfate reduction appeared to be limited by sulfate and methanogenesis accounted for over 80% of the anaerobic mineralization. At low anaerobic mineralization rates, measured in winter and spring, sulfate reduction was predominant.<br/> There was little methanogenesis below 5 cm depth in the sediment which indicated a rapid decrease of degradable organic matter with depth. There was a remarkable difference, especially in winter, between methane fluxes which were measured in batch experiments and those calculated from the concentration profiles in the sediment. These differences may be due to methane diffusing upward from deep layers.

The study of human dimensions of global climatic change is still in the initial stage of development. Several attempts have been undertaken to define sensible research strategies in the field but until now relatively little empirical work has been undertaken and there is a lack of sound theoretical arguments. The present paper presents a theory-based empirical study of determinants influencing the probability that somebody takes climate-relevant environmental action. Important methodological differences between current models of climate dynamics and models of human reality are discussed in order to build three models of climate-related environmental action. A model focussed on the information transfer from science to the public at large is compared with a model focussed on sociodemographic characteristics and with a model focussed on socio-cultural variables like interpersonal rules and social networks. The hypothesis that the latter model is strongly superior to the former ones is tested and confirmed. Some implications for interdisciplinary cooperation and for policy making are discussed.

As potential to adapt to environmental stress can be essential for population persistence, knowledge on the genetic architecture of local adaptation is important for conservation genetics. We investigated the relative importance of additive genetic, dominance and maternal effects contributions to acid stress tolerance in two moor frog (<I>Rana arvalis</I>) populations originating from low and neutral pH habitats. Experiments with crosses obtained from artificial matings revealed that embryos from the acid origin population were more tolerant to low pH than embryos from the neutral origin population in embryonic survival rates, but not in terms of developmental stability, developmental and growth rates. Strong maternal effect and small additive genetic contributions to variation were detected in all traits in both populations. In general, dominance contributions to variance in different traits were of similar magnitude to the additive genetic effects, but dominance effects outweighed the additive genetic and maternal effects contributions to early growth in both populations. Furthermore, the expression of additive genetic variance was independent of pH treatment, suggesting little additive genetic variation in acid stress tolerance. The results suggest that although local genetic adaptation to acid stress has taken place, the current variation in acid stress tolerance in acidified populations may owe largely to non-genetic effects. However, low but significant heritabilities (h<SUP>2</SUP> ≈ 0.07-0.22) in all traits – including viability itself – under a wide range of pH conditions suggests that environmental stress created by low pH is unlikely to lower moor frog populations' ability to respond to selection in the traits studied. Nevertheless, acid conditions could lower populations' ability to respond to selection in the long run through reduction in effective population size.

To date, evidence for the degradation of benzene under anaerobic conditions has been established only in few studies under field and laboratory conditions. Recently, we demonstrated the mineralization of benzene under sulfate-reducing conditions in a large-scale column experiment at a field site by balancing electrons (Vogt et al. in Biodegradation, 2007, in press). Here, from a modelling approach, kinetic Monod parameters are estimated for the degradation of benzene in the columns, Monod kinetics proved useful to simulate benzene concentrations at the column outflow. The uncertainty of the obtained parameters is determined in a sensitivity analysis. A total mass of degraded benzene of 23 g or 80% of the total influx over a period of three months was calculated. The estimated maximum utilization rate was calculated to be around 70 times lower than from aerobic benzene degradation experiments.

Reactive tracer tests are performed to derive flow, transport and in situ biodegradation parameters. This paper describes the 3D simulation of a reactive tracer test using the transition probability geostatistical approach. Fifty different equally probable aquifer realizations were generated based on the geological information of 107 boreholes in an area of 62,500 m<SUP>2</SUP>. One realization was chosen for the reactive transport simulation based on the results of groundwater flow modeling and on particle tracking calculations for the site. Field velocities at the site vary between 0.4 and 3 m/d. The transport of the reactive tracers deuterium ring labeled toluene-d<SUB>5</SUB> and fully deuterated toluene-d<SUB>8</SUB> was simulated and first-order biodegradation rates of 0.017 d<SUP>−1</SUP> for toluene-d<SUB>5</SUB> and 0.012 d<SUP>−1</SUP> for toluene-d<SUB>8</SUB> were determined.

The degree to which genetic variation in a given trait varies among different populations of the same species and across different environments has seldom been quantified in wild vertebrate species. We investigated the expression of genetic variability and maternal effects in three larval life-history traits of the amphibian <I>Rana temporaria</I>. In a factorial laboratory experiment, five widely separated populations (max. 1600 km) were subjected to two different environmental treatments. Animal model analyses revealed that all traits were heritable (<I>h</I><SUP>2</SUP>≈0·20) in all populations and under most treatment combinations. Although the cross-food treatment genetic correlations were close to unity, heritabilities under a restricted food regime tended to be lower than those under an <I>ad libitum</I> food regime. Likewise, maternal effects (<I>m</I><SUP>2</SUP>≈0·05) were detected in most traits, and they tended to be most pronounced under restricted food conditions. We detected several cross-temperature genetic and maternal effects correlations that were lower than unity, suggesting that genotype–environment interactions and maternal effect–environment interactions are a significant source of phenotypic variation. The results reinforce the perspective that although the expression of genetic and maternal effects may be relatively homogeneous across different populations of the same species, local variation in environmental conditions can lead to significant variation in phenotypic expression of quantitative traits through genotype–environment and maternal effect–environment interactions.

In a choice experiment, households in Vietnam are offered flood insurance to mitigate increasing catastrophic flood risks due to climate change. Participants are asked to choose their most preferred insurance policy given expected future flood and mortality risks, insurance cover and associated insurance premiums. Although not affordable to everyone, there exists substantial demand for flood insurance. Insurance demand is spatially differentiated, non-linear in flood probabilities and mortality risks, and subject to significant preference heterogeneity. Since respondents are unfamiliar with the concept of flood insurance and education levels are low, choice consistency tests were conducted. These show that choice consistency depends on a combination of respondent characteristics, such as gender and education level, and experimental design characteristics.