No abstract

Abstract.  Climate change affects many ecosystems on earth. If not dying out or migrating, the species affected have to survive the altered conditions, including changes in community structure. It is, however, usually difficult to distinguish changes caused by a changing climate from other factors. Forestry is considered to be the major disturbance factor in Swedish forests. Here, we use forest lake data sets from 1996 and 2006 which include species abundance data for dragonfly larvae, water plant structure, forest age and forestry measures during a period of 25 years: from 1980 to 2005. Hence, we were able to discriminate between forestry effects and changes in species composition driven by recent climate change. We explored effects on regional species composition, species abundance and ecosystem functions, such as changes in niche use, utilising dragonflies (Odonata) as model organisms. Our results show that dragonflies react rapidly to climate change, showing strong responses over such a short time span as 10 years. We observed changes in both species composition and abundance; former rare species have become more frequent and now occur in lakes of a wider quality range, while former widespread species have become more selective in their choice of waters. The new communities harbour about the same number of species as before, but seen from a regional perspective, diversity is reduced. We predict that the altered species composition and abundance might raise new demands in conservation planning as well as altering the ecological functions of the aquatic systems.

We conclude that cells in benign prostate tissue and cells in well-differentiated prostate carcinoma show great similarities in synthesis, storage, and release of prostasomes. However, this does not exclude the presence of other changes, for instance biochemical ones, in the prostasomes.

Since the three prostasome types were isolated from different environments, our data support the view that the common characteristics were prostasome-genuine.

No abstract

Among terrestrial arthropods, the dragonfly species Pantala flavescens is remarkable due to their nearly global distribution and extensive migratory ranges; the largest of any known insect. Capable of migrating across oceans, the potential for high rates of gene flow among geographically distant populations is significant. It has been hypothesized that P. flavescens may be a global panmictic population but no sufficient genetic evidence has been collected thus far. Through a population genetic analysis of P. flavescens samples from North America, South America, and Asia, the current study aimed to examine the extent at which gene flow is occurring on a global scale and discusses the implications of the genetic patterns we uncovered on population structure and genetic diversity of the species. This was accomplished using PCR-amplified cytochrome oxidase one (CO1) mitochondrial DNA data to reconstruct phylogenetic trees, a haplotype network, and perform molecular variance analyses. Our results suggested high rates of gene flow are occurring among all included geographic regions; providing the first significant evidence that Pantala flavescens should be considered a global panmictic population.

life history traits in temporary and perennial waters: comparisons among three pairs of sibling dragonfly species. Á/ Oikos 108: 609 Á/617.Identifying and examining traits that influence the distribution of species is crucial to the understanding of community structure. Theory predicts that traits should differ between species that live in temporary and permanent waters because of differing major environmental variables; viz drying out and predator presence, respectively. Species, however, will also be influenced by their evolutionary history, i.e. by the traits of their common ancestors. We studied differences in life history and behaviour traits in a series of laboratory experiments using pairs of dragonfly species out of three genera of Namibian Libellulidae (Odonata) with one species from each type of habitat. As predicted, growth rates were significantly higher in the temporary water species compared to the permanent water species. Activity and foraging, in contrast, differed between the genera, but did not differ between the habitat types. Hence, our study implies that the behavioural traits are influenced by phylogenetic inertia rather than by the habitat variables, while growth rate is adapted to the habitat. We argue that in all three genera one species has diverged recently from a sister species that lives in the original habitat of the genus, which may be temporary waters in Crocothemis Brauer and in Orthetrum Newman, and permanent waters in Trithemis Brauer. The behavioural traits may therefore be less well adapted. Rapid growth may be the more relevant trait because it is crucial to survival in temporary waters.

We conclude that prostasomes produced by the cells of vertebral metastases of prostate cancer are distributed both intracellularly and extracellularly in the interstitial spaces of the tissue. Thus, prostasomes of metastases could perhaps be exploited as targets for immunodiagnosis and/or immunotherapy.