• Energy Research
• health sciences close
• 13. Climate action close
• 3. Good health close
• RU close
• EC close

AbstractMarine encrusting communities play vital roles in benthic ecosystems and have major economic implications with regards to biofouling. However, their ability to persist under projected warming scenarios remains poorly understood and is difficult to study under realistic conditions. Here, using heated settlement panel technologies, we show that after 18 months Antarctic encrusting communities do not acclimate to either +1 °C or +2 °C above ambient temperatures. There is significant up-regulation of the cellular stress response in warmed animals, their upper lethal temperatures decline with increasing ambient temperature and population genetic analyses show little evidence of differential survival of genotypes with treatment. By contrast, biofilm bacterial communities show no significant differences in community structure with temperature. Thus, metazoan and bacterial responses differ dramatically, suggesting that ecosystem responses to future climate change are likely to be far more complex than previously anticipated.

Vector-borne transmitted helminthic zoonosis affects the health and economy of both developing and developed countries. The concept of episystem includes the set of biological, environmental, and epidemiological elements of these diseases in defined geographic and temporal scales. Dirofilariasis caused by different species of the genusDirofilariais a disease affecting domestic and wild canines and felines and man, transmitted by different species of culicid mosquitoes. This complexity is increased becauseDirofilariaspecies harbor intracellular symbiontWolbachiabacteriae, which play a key role in the embryogenesis and development of dirofilariae and in the inflammatory pathology of the disease. In addition, the vector transmission makes the dirofilariasis susceptible to the influence of the climate and its variations. The present review addresses the analysis of dirofilariasis from the point of view of the episystem, analyzing the complex network of interactions established between biological components, climate, and factors related to human activity, as well as the different problems they pose. The progress of knowledge on human and animal dirofilariasis is largely due to the multidisciplinary approach. Nevertheless, different aspects of the disease need to continue being investigated and cooperation between countries and specialists involved should be intensified.

About 10,000 years ago, when the million-year-long Pleistocene epoch gave way to the ongoing Holocene epoch, much of the world's ecosystems changed. In what is now northern Siberia, vast numbers of large animals, among them mammoths, woolly rhinoceroses, and yaks, both thrived on and nurtured the steppes that, compared to other northern regions of the world, remained relatively unscathed from the repeated advances and retreats of ice sheets. Even so, the steppes there gave way to silt, dust, and ice-based tundra landscapes dominated in some places by forests and in others by mosses. The large animals disappeared. [Sergey Zimov][1], director of the Northeast Science Station in Cherskii in the Republic of Sakha (Yakutia), argues that climate change may not have been the primary reason behind the demise of this Pleistocene ecosystem. Instead, he says changing hunting practices wiped out the large animals whose absence led to the ecosystem shifts. He and his colleagues now are reintroducing bison, Yakutian horses, and other animals, eventually even tigers, in an attempt to reconstitute the Pleistocene ecosystem. The experiment will test the hypothesis that humans, rather than climate change, caused the ecosystem shift at the beginning of the Holocene. The stabilization of the northern tundra soils that this reconstitution could bring also could prevent the release of vast amount of carbon now sequestered in the Siberian soils but in danger of being released in the warmer times projected for the future. All essays appearing in this series can be found online at [www.sciencemag.org/sciext/globalvoices/][2] * * * [1]: http://www.sciencemag.org/cgi/content/full/308/5723/796 [2]: http://www.sciencemag.org/sciext/globalvoices/

The intensity of climatic changes and human activities is increasing every year. The general consequence of these processes for freshwater ecosystems can be a dissolved oxygen decrease. There is also a possibility of a reduction in geomagnetic field intensity due to a reversal of the Earth’s magnetic poles. It is assumed that the magnetic poles’ reversal may proceed relatively quickly and coincide with global climatic changes. To evaluate the influence of these processes on aquatic organisms, we studied the effects of different dissolved oxygen levels (2 mg/L, 5 mg/L, and 8 mg/L) under the geomagnetic field (51.7 ± 0.2 μT) and hypomagnetic field (0 ± 0.2 μT) on the model freshwater crustacean Daphnia magna Straus. It was found that reduced oxygen levels and the hypomagnetic field led to a decrease in the sizes of parental females, a reduction in the number of produced offspring, and an increase in the period between broods. The newborns from the first brood in the hypomagnetic field were larger than that from the geomagnetic field. The dissolved oxygen level and magnetic environment affected the age of the first brood release and caudal spine length. The results imply that the probable coincidence of the geomagnetic pole reversal and the decrease in the dissolved oxygen level due to global climatic and geophysical processes will have a more negative impact on freshwater crustaceans than the occurrence of these processes at different times.

Addition of ethanol and some other primary alcohols, except methanol, to cells and protoplasts (but not membrane particles) considerably stimulated the rate of oxygen consumption. This additional respiration was strongly inhibited by 0.1 mM KCN. The cyanide inhibition curve of endogenous substrate oxidation was slightly biphasic while in the presence of ethanol it became clearly biphasic having Ki values of approx. 0.1 and 0.5 mM. Based on the steady-state cytochrome spectra in the presence of 0.1 mM KCN, we attributed the lower Ki to cytochrome a602. Proteolysis of protoplasts external membrane proteins did not change the rate of endogeneous substrate oxidation but prevented the inhibition of this respiration by low concentrations of KCN and stimulation of oxygen consumption by ethanol. The activity of NAD(+)-dependent ethanol dehydrogenase in the cytoplasm was found to be 520 nmol NADH- x min-1 x mg-1 protein. Proteolysis of external membrane proteins apparently inhibits the operation of the cytochrome a602-containing electron transport branch inducing the suppression of electron flow from NADH to oxygen.

Chronic ethanol consumption in high doses is associated with constitutively elevated activity of the serum alcohol dehydrogenase I (ADH I) isoform, which demonstrates a high affinity not only for ethanol but also for a number of bioamine metabolites. Such excessive ADH activity is probably associated with disruptions in the metabolism of neurotransmitters (dopamine, serotonin, and norepinephrine) and subsequent long-term changes in the activity of their receptors. Ultimately, a stable depressive-like condition contributes to the development of patients' craving for ethanol intake, frequent disruptions during therapy, and low efficacy of treatment. We applied active immunization against ADH to investigate its efficacy in the reduction of excessive serum ADH activity and regulation of ethanol consumption by chronically ethanol-fed Wistar rats (15% ethanol, 4 months, free-choice method), and we analyzed its ability to influence the levels of bioamines in the brain. Immunization (2 injections, 2-week intervals) was performed using a combination of recombinant horse ADH isozyme as an antigen and 2% aluminum hydroxide-based adjuvant. The efficacy of immunization was demonstrated by the production of high titers of ADH-specific antibodies, which was consistent with the significantly reduced ADH activity in the serum of chronically ethanol-fed rats. On the 26th day after the first vaccine injection, we registered significantly lower levels of alcohol consumption compared to ethanol-fed control animals, and the difference reached 16% on the 49th day of the experiment. These observations were accompanied by data that showed reduced levels of ethanol preference in immunized rats. Chronic alcohol drinking led to a decrease in dopamine and DOPAL (a direct dopamine metabolite and a high-affinity ADH substrate) levels in the striatum,while immunization neutralized this effect. Additionally, we observed that inhibition of serum ADH activity caused a decrease in peak dopamine levels during acute alcohol intake in chronically ethanol-fed rats during ethanol withdrawal that was associated with reduced tyrosine hydroxylase activity in the striatum. The obtained data suggest a significant contribution of ADH to the changes in neurotransmitter systems during chronic alcohol consumption and make available new prospects for developing innovative strategies for treatment of excessive alcohol intake.

Although sediments of small boreal humic lakes are important carbon stores and greenhouse gas sources, the composition and structuring mechanisms of their microbial communities have remained understudied. We analyzed the vertical profiles of microbial biomass indicators (PLFAs, DNA and RNA) and the bacterial and archaeal community composition (sequencing of 16S rRNA gene amplicons and qPCR of mcrA) in sediment cores collected from a typical small boreal lake. While microbial biomass decreased with sediment depth, viable microbes (RNA and PLFA) were present all through the profiles. The vertical stratification patterns of the bacterial and archaeal communities resembled those in marine sediments with well-characterized groups (e.g. Methanomicrobia, Proteobacteria, Cyanobacteria, Bacteroidetes) dominating in the surface sediment and being replaced by poorly-known groups (e.g. Bathyarchaeota, Aminicenantes and Caldiserica) in the deeper layers. The results also suggested that, similar to marine systems, the deep bacterial and archaeal communities were predominantly assembled by selective survival of taxa able to persist in the low energy conditions. Methanotrophs were rare, further corroborating the role of these methanogen-rich sediments as important methane emitters. Based on their taxonomy, the deep-dwelling groups were putatively organo-heterotrophic, organo-autotrophic and/or acetogenic and thus may contribute to changes in the lake sediment carbon storage.