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Field experiments that expose terrestrial ecosystems to climate change factors by manipulations are expensive to maintain, and typically only last a few years. Plant biomass is commonly used to assess responses to climate treatments and to predict climate change impacts. However, response to the treatments might be considerably different between the early years and a decade later. The aim of this data analysis was to develop and apply a method for evaluating changes in plant biomass responses through time, in order to provide a firm basis for discussing how the 'short-term' response might differ from the 'long-term' response. Across 22 sites situated in the northern hemisphere, which covered three continents, and multiple ecosystems (grasslands, shrublands, moorlands, forests, and deserts), we evaluated biomass datasets from long-term experiments with exposure to elevated CO2 (eCO2), warming, or drought. We developed methods for assessing biomass response patterns to the manipulations using polynomial and linear (piecewise) model analysis and linked the responses to site-specific variables such as temperature and rainfall. Polynomial patterns across sites indicated changes in response direction over time under eCO2, warming, and drought. In addition, five distinct pattern types were confirmed within sites: 'no response', 'delayed response', 'directional response', 'dampening response', and 'altered response' patterns. We found that biomass response direction was as likely to change over time as it was to be consistent, and therefore suggest that climate manipulation experiments should be carried out over timescales covering both short- and long-term responses, in order to realistically assess future impacts of climate change.

Establishing and maintaining protected areas (PAs) are key tools for biodiversity conservation. However, this approach is insufficient for many species, particularly those that are wide-ranging and sparse. The cheetah Acinonyx jubatus exemplifies such a species and faces extreme challenges to its survival. Here, we show that the global population is estimated at ∼7,100 individuals and confined to 9% of its historical distributional range. However, the majority of current range (77%) occurs outside of PAs, where the species faces multiple threats. Scenario modeling shows that, where growth rates are suppressed outside PAs, extinction rates increase rapidly as the proportion of population protected declines. Sensitivity analysis shows that growth rates within PAs have to be high if they are to compensate for declines outside. Susceptibility of cheetah to rapid decline is evidenced by recent rapid contraction in range, supporting an uplisting of the International Union for the Conservation of Nature (IUCN) Red List threat assessment to endangered. Our results are applicable to other protection-reliant species, which may be subject to systematic underestimation of threat when there is insufficient information outside PAs. Ultimately, conserving many of these species necessitates a paradigm shift in conservation toward a holistic approach that incentivizes protection and promotes sustainable human–wildlife coexistence across large multiple-use landscapes.

In this paper some of the technological platforms developed in our group for biological cell analysis will be highlighted. The paper first presents a short introduction pinpointing the advantages of using micro and nano technology in cellular studies. The issues of requiring transient analysis while working in a biological environment maintaining the cells viability and adding analyte are addressed and discussed. An example of a cell culturing chamber useful for both adherent and non-adherent cells, with the capability of adding analyte is given, a small discussion of in vitro cellular studies mimicking the in vivo situation is presented and an example of surface modification for cellular growth is described. Then novel electronic sensor platforms are discussed and an example of a nanosensor with electronic readout is given utilizing both micro- and nanotechnology. Finally an example of sorting cells using dielectrophoresis will be given, aiming at early cancer detection.

Klimaændringerne vil ændre basale faktorer i terrestriske økosystemer som vandforhold og temperatur. Disse faktorer har direkte og indirekte indflydelse på alle processer i økosystemet. Klimaændringer vil derfor påvirke levevilkårene for planter og dyr gennem en kaskade af effekter, som vil ændre økosystemernes artssammensætning, struktur og funktion. Klimaændringers påvirkning af økosystemets processer, og planter og dyrs respons på de ændrede vilkår, er undersøgt i større klimaforsøg og studier langs klimatiske gradienter gennem de seneste år. Resultater fra danske klimaforsøg på heder viser, at de komplekse sammenhænge mellem økosystemets processer og samspillet med de klimatiske vilkår medfører, at klimaets effekter på økosystemerne er svære at forudsige.

Pigs in 2 herds with persistent problems with post weaning edema disease caused by infection with verotoxin-2e (VT2e)-producing Escherichia coli O139 were treated with a VT2e-toxoid vaccine. Treatment was performed as a randomized blind field trial with parallel treatment and non-vaccinated control groups. In 1 herd, a group of pigs was injected with adjuvant alone. Pigs were vaccinated at 1 and 3 wk of age and weaned at 4 wk of age. The effect of vaccination was measured by average daily weight gain (ADG), mortality due to edema disease within the 1st 4 wk after weaning, and weight at 3-6 mo of age. Pathological and microbiological examinations were performed on all pigs that died during the 1st 4 wk post weaning. Only pigs from which VT2e+, F18+ E. coli O139 was isolated were categorized as "death due to edema disease." The serological response to vaccination was evaluated by an indirect ELISA. Vaccination had a statistically significant effect on the level of antibodies specific for VT2e in both herds. Vaccination resulted in a statistically significant increase in ADG in the nursery period but not in the grower-finishing period. Vaccination had a statistically significant effect on mortality due to edema disease with an odds ratio of 0.039, indicating that there was almost total elimination of mortality due to the disease in the vaccine groups.