Evaluating the Connectivity of a Protected Areas' Network under the Prism of Global Change: The Efficiency of the European Natura 2000 Network for Four Birds of Prey

Climate and land use changes are major threats to biodiversity. To preserve biodiversity, networks of protected areas have been established worldwide, like the Natura 2000 network across the European Union (EU). Currently, this reserve network consists of more than 26000 sites covering more than 17% of EU terrestrial territory. Its efficiency to mitigate the detrimental effects of land use and climate change remains an open research question. Here, we examined the potential current and future geographical ranges of four birds of prey under scenarios of both land use and climate changes. By using graph theory, we examined how the current Natura 2000 network will perform in regard to the conservation of these species. This approach determines the importance of a site in regard to the total network and its connectivity. We found that sites becoming unsuitable due to climate change are not a random sample of the network, but are less connected and contribute less to the overall connectivity than the average site and thus their loss does not disrupt the full network. Hence, the connectivity of the remaining network changed only slightly from present day conditions. Our findings highlight the need to establish species-specific management plans with flexible conservation strategies ensuring protection under potential future range expansions. Aquila pomarina is predicted to disappear from the southern part of its range and to become restricted to northeastern Europe. Gyps fulvus, Aquila chrysaetos, and Neophron percnopterus are predicted to locally lose some suitable sites; hence, some isolated small populations may become extinct. However, their geographical range and metapopulation structure will remain relatively unaffected throughout Europe. These species would benefit more from an improved habitat quality and management of the existing network of protected areas than from increased connectivity or assisted migration.     

Developmental stage on day-5 and fragmentation rate on day-3 can influence the implantation potential of top-quality blastocysts in IVF cycles with single embryo transfer

Background  

In IVF-ICSI cycles with single embryo transfer (SET), embryo selection for transfer is of crucial importance. The present study aimed to define which embryo parameters might be related to the implantation potential of advanced blastocysts.     

Enhancement of Tight Junctional Barrier Function by Micronutrients: Compound-Specific Effects on Permeability and Claudin Composition

Amid an increasing number of reports in the literature concerning epithelial barrier enhancement by various nutrient compounds, there has never been a study performing side-by-side comparisons of these agents in a single epithelial model. We compare five nutrient compounds (previously reported in various epithelial models to enhance barrier function) regarding their ability to increase transepithelial electrical resistance (R_t) and decrease transepithelial mannitol permeability (J_m) across LLC-PK₁ renal epithelial cell layers. The effects of these nutrients on the abundance of various tight junctional proteins are also compared. In the overall group of nutrients tested - zinc, indole, quercetin, butyrate and nicotine - only nicotine failed to improve barrier function by either parameter. Nicotine also was without effect on tight junctional proteins. Quercetin simultaneously increased R_t and decreased J_m. Zinc, butyrate and indole only exhibited statistically significant enhancement of R_t. Each of these four effective nutrient compounds had unique patterns of effects on the panel of tight junctional proteins studied. No two compounds produced the same pattern of effects. This unique pattern of effects on tight junctional complex composition by each compound establishes the chance for additive or even synergistic improvement of barrier function by combinations of compounds. A synergistic effect of the combination of quercetin and zinc on R_t is shown.     

Grazing effects on plant functional group diversity in Mediterranean shrublands

Grazing is one of the prevalent human activities that even today are taking place inside protected areas with direct or indirect effects on ecosystems. In this study we analyzed the effects of grazing on plant species diversity, plant functional group (PFG) diversity and community composition of shrublands. We analyzed plant diversity data from 582 sampling plots located in 66 protected areas of the Greek Natura 2000 network, containing in total 1102 plant species and subspecies. We also classified a priori all plant species in seven PFGs: annual forbs, annual grasses/sedges, legumes, perennial forbs, perennial grasses/sedges, small shrubs and tall shrubs. For each site, grazing intensity was estimated in four classes (no grazing, low, medium and high grazing intensity). We found that, at the spatial and temporal scale of this study, as grazing intensity increased, so did total species richness. However, each PFG displayed a different response to grazing. Short-lived species (annual grasses or forbs and legumes) benefited from grazing and their species richness and proportion in the community increased with grazing. Perennial grasses and forbs species richness increased with grazing intensity, but their dominance decreased, since their proportion in the community declined. Short shrub species richness remained unaffected by grazing, while tall shrub diversity decreased. Finally, in sites without grazing the spatial pattern of species richness of the different PFGs was not congruent with each other, while in grazed sites they were significantly positively correlated (with the exception of tall shrubs). This finding may imply that grazing is a selective pressure organizing the community structure, and imposing a certain contribution of each PFG. So, in Mediterranean shrublands in protected areas with a long historical record of grazing, it seems that grazing promotes species diversity and its continuation on a portion of the landscape may be a necessary part of an effective management plan.     

Biotechnological production of ethanol: Biochemistry,processes and technologies

The majority of environmental problems arise from the use of conventional energy sources. The liability of such problems along with the reduction of fossil energy resources has led to the global need for alternative renewable energy sources. Using renewable biofuels as energy sources is of remarkable and continuously growing importance. Producing bioethanol through conversion of waste and residual biomass can be a viable and important perspective. In the first part of this review, general concepts, approaches and considerations concerning the utilization of the most important liquid biofuels, namely biodiesel and bioethanol, are presented. Unlike biodiesel (specifically first generation biodiesel), the production of bioethanol is exclusively based on the utilization of microbial technology and fermentation engineering. In the second part of this review, the biochemistry of ethanol production, with regards to the use of hexoses, pentoses or glycerol as carbon sources, is presented and critically discussed. Differences in the glycolytic pathways between the major ethanol‐producing strains (Saccharomyces cerevisiae and Zymomonas mobilis) are presented. Regulation between respiration and fermentation in ethanol‐producing yeasts, viz. effects “Pasteur”, “Crabtree”, “Kluyver” and “Custers”, is discussed. Xylose and glycerol catabolism related with bioethanol production is also depicted and commented. The technology of the fermentation is presented along with a detailed illustration of the substrates used in the process and in pretreatment of lignocellulosic biomass, and the various fermentation configurations employed (separate hydrolysis and fermentation, simultaneous saccharification and fermentation, simultaneous saccharification and co‐fermentation and consolidated bioprocessing). Finally, the production of bioethanol under non‐aseptic conditions is presented and discussed.     

Inhibition of intestinal ischemia/repurfusion induced apoptosis and necrosis via down-regulation of the NF-kB, c-Jun and caspace-3 expression by epigallocatechin-3-gallate administration

Intestinal ischemia/reperfusion (I/R) produces reactive oxygen species (ROS) activating signal transduction and apoptosis. The aim of this study was to evaluate the effect of (-)-epigallocatechin-3-gallate (EGCG) administration in inhibition of apoptosis by attenuating the expression of NF-kB, c-Jun and caspace-3 in intestinal I/R. Thirty male wistar rats were used. Group A sham operation, B I/R, C I/R-EGCG 50 mg/kg ip. Intestinal ischemia was induced for 60 min by clamping the superior mesenteric artery. Malondialdehyde (MDA), myeloperoxidase (MPO), light histology, Fragment End Labelling of DNA (TUNEL), immunocytochemistry for NF-kB, c-Jun and caspace-3 analysis in intestinal specimens were performed 120 min after reperfusion. Apoptosis as indicated by TUNEL and Caspace-3, NF-kB and c-Jun was widely expressed in I/R group but only slightly expressed in EGCG treated groups. MDA and MPO showed a marked increase in the I/R group and a significant decrease in the EGCG treated group. Light histology showed preservation of architecture in the EGCG treated group. In conclusion, EGCG pre-treatment is likely to inhibit intestinal I/R-induced apoptosis by down-regulating the expression of NF-kB, c-Jun and caspase-3.     

Modeling Lipid Accumulation and Degradation in Yarrowia lipolytica Cultivated on Industrial Fats

A modeling approach was used to quantify the kinetic behavior of a Yarrowia lipolytica strain capable of producing significant lipid amounts when cultivated on industrial fats. Biomass and cellular lipid evolution were successfully simulated, while the optimized parameter values were similar to those experimentally measured. The maximum specific formation rate of fat-free biomass seemed unaffected by the substrate fatty acid composition. On the contrary, the maximum concentration of lipid accumulated inside the yeast cell, as well as the maximum specific accumulation rate of cellular lipids, was favored in high stearic acid content media. The microorganism presented the tendency to degrade its accumulated lipids, although remarkable substrate fat amounts remained unconsummated in the culture medium. This degradation slowly occurred in the yeast cell as the specific rate of the intracellular carbon pool (storage lipid consumption) was significantly lower compared with that of the extracellular carbon pool (substrate fat). However, the fat-free biomass yield on storage lipids (g of fat-free biomass formed per g of storage lipids consumed) was higher than the one on the substrate (g of fat-free biomass formed per g of medium fat consumed). Received: 26 June 2002 / Accepted: 22 July 2002