Can wild ungulate carcasses provide enough biomass to maintain avian scavenger populations? An empirical assessment using a bio-inspired computational model

Background: The reduction in the amount of food available for European avian scavengers as a consequence of restrictive public health policies is a concern for managers and conservationists. Since 2002, the application of several sanitary regulations has limited the availability of feeding resources provided by domestic carcasses, but theoretical studies assessing whether the availability of food resources provided by wild ungulates are enough to cover energetic requirements are lacking. Methodology/Findings: We assessed food provided by a wild ungulate population in two areas of NE Spain inhabited by three vulture species and developed a P System computational model to assess the effects of the carrion resources provided on their population dynamics. We compared the real population trend with to a hypothetical scenario in which only food provided by wild ungulates was available. Simulation testing of the model suggests that wild ungulates constitute an important food resource in the Pyrenees and the vulture population inhabiting this area could grow if only the food provided by wild ungulates would be available. On the contrary, in the Pre-Pyrenees there is insufficient food to cover the energy requirements of avian scavenger guilds, declining sharply if biomass from domestic animals would not be available. Conclusions/Significance: Our results suggest that public health legislation can modify scavenger population trends if a large number of domestic ungulate carcasses disappear from the mountains. In this case, food provided by wild ungulates could be not enough and supplementary feeding could be necessary if other alternative food resources are not available (i.e. the reintroduction of wild ungulates), preferably in European Mediterranean scenarios sharing similar and socio-economic conditions where there are low densities of wild ungulates. Managers should anticipate the conservation actions required by assessing food availability and the possible scenarios in order to make the most suitable decisions.

Engineered Trx2p industrial yeast strain protects glycolysis and fermentation proteins from oxidative carbonylation during biomass propagation

Background: In the yeast biomass production process, protein carbonylation has severe adverse effects since it diminishes biomass yield and profitability of industrial production plants. However, this significant detriment of yeast performance can be alleviated by increasing thioredoxins levels. Thioredoxins are important antioxidant defenses implicated in many functions in cells, and their primordial functions include scavenging of reactive oxygen species that produce dramatic and irreversible alterations such as protein carbonylation. Results: In this work we have found several proteins specifically protected by yeast Thioredoxin 2 (Trx2p). Bidimensional electrophoresis and carbonylated protein identification from TRX-deficient and TRX-overexpressing cells revealed that glycolysis and fermentation-related proteins are specific targets of Trx2p protection. Indeed, the TRX2 overexpressing strain presented increased activity of the central carbon metabolism enzymes. Interestingly, Trx2p specifically preserved alcohol dehydrogenase I (Adh1p) from carbonylation, decreased oligomer aggregates and increased its enzymatic activity. Conclusions: The identified proteins suggest that the fermentative capacity detriment observed under industrial conditions in T73 wine commercial strain results from the oxidative carbonylation of specific glycolytic and fermentation enzymes. Indeed, increased thioredoxin levels enhance the performance of key fermentation enzymes such as Adh1p, which consequently increases fermentative capacity.

Cherenkov mesons as in-medium quark energy loss

We recently showed that a heavy quark moving sufficiently fast through a quark-gluon plasma may lose energy by Cherenkov-radiating mesons [1]. Here we review our previous holographic calculation of the energy loss in N=4 Super Yang-Mills and extend it to longitudinal vector mesons and scalar mesons. We also discuss phenomenological implications for heavy-ion collision experiments. Although the Cherenkov energy loss is an O(1/Nc) effect, a ballpark estimate yields a value of dE/dx for Nc=3 which is comparable to that of other mechanisms.

Cherenkov mesons as in-medium quark energy loss

We recently showed that a heavy quark moving sufficiently fast through a quark-gluon plasma may lose energy by Cherenkov-radiating mesons [1]. Here we review our previous holographic calculation of the energy loss in N=4 Super Yang-Mills and extend it to longitudinal vector mesons and scalar mesons. We also discuss phenomenological implications for heavy-ion collision experiments. Although the Cherenkov energy loss is an O(1/Nc) effect, a ballpark estimate yields a value of dE/dx for Nc=3 which is comparable to that of other mechanisms.

A New Mechanism of Quark Energy Loss

We show that a heavy quark moving sufficiently fast through a quark-gluon plasma may lose energy by Cherenkov-radiating mesons. We demonstrate that this takes place in all strongly coupled, large-Nc plasmas with a gravity dual. The energy loss is exactly calculable in these models despite being an O(1/Nc)-effect. We discuss phenomenological implications for heavy-ion collision experiments.

Does ear C sink strength contributes to the overcoming of photosynthetic acclimation of wheat plants exposed to elevated CO2?

Wheat plants (Triticum durum Desf., cv. Regallo) were grown in the field to study the effects of contrasting [CO2] conditions (700 versus 370 μmol mol−1) on growth, photosynthetic performance, and C management during the post-anthesis period. The aim was to test whether a restricted capacity of sink organs to utilize photosynthates drives a loss of photosynthetic capacity in elevated CO2. The ambient 13C/12C isotopic composition (δ13C) of air CO2 was changed from-10.2 in ambient [CO2] to-23.6 under elevated [CO2] between the 7th and the 14th days after anthesis in order to study C assimilation and partitioning between leaves and ears. Elevated [CO2] had no significant effect on biomass production and grain filling, and caused an accumulation of C compounds in leaves. This was accompanied by up-regulation of phosphoglycerate mutase and ATP synthase protein content, together with down-regulation of adenosine diphosphate glucose pyrophosphatase protein. Growth in elevated [CO2] negatively affected Rubisco and Rubisco activase protein content and induced photosynthetic down-regulation. CO2 enrichment caused a specific decrease in Rubisco content, together with decreases in the amino acid and total N content of leaves. The C labelling revealed that in flag leaves, part of the C fixed during grain filling was stored as starch and structural C compounds whereas the rest of the labelled C (mainly in the form of soluble sugars) was completely respired 48 h after the end of labelling. Although labelled C was not detected in the δ13C of ear total organic matter and respired CO2, soluble sugar δ13C revealed that a small amount of labelled C reached the ear. The 12CO2 labelling suggests that during the beginning of post-anthesis the ear did not contribute towards overcoming flag leaf carbohydrate accumulation, and this had a consequent effect on protein expression and photosynthetic acclimation.

Establishing the Stages and Processes of Change for Weight Loss by Consensus of Experts

The present study aimed to establish, by a consensus of experts, the stages and processes of change for weight management in overweight and obese people. The first step involved developing two questionnaires aimed at assessing stages and processes of change for weight loss in overweight and obese people. The processes-ofchange questionnaire consisted of 12 subscales, and contained 107 items. A three-round Delphi study was carried out through a website, where participants were asked to give their opinion about the representativeness and clarity of the scale items. The stages-of-change questionnaire consisted of five items and was presented in the final round of the study. A team of 66 experts in the obesity field from 29 countries participated in the study. They were selected either because they belonged to the organizing committee of international associations related to obesity, or because of their research career. The required changes in the questionnaire were made according to the opinions of the participants. Some of these were the result of the group statistical response, whereas others were due to the suggestions made by the participants. A final version of the questionnaire consisting of 63 items was eventually obtained. The present study produced two questionnaires to assess stages and processes of change for weight management. The strength of the study lies in the consensus reached by the panel of experts in order to establish the required content of the questionnaires. The two measures provide useful tools for practitioners who wish to tailor weight-management interventions according to transtheoretical model constructs.

Moths behaving like butterflies. Evolutionary loss of long range attractant pheromones in Castniid Moths: A Paysandisia archon model

Background: In the course of evolution butterflies and moths developed two different reproductive behaviors. Whereas butterflies rely on visual stimuli for mate location, moths use the"female calling plus male seduction" system, in which females release long-range sex pheromones to attract conspecific males. There are few exceptions from this pattern but in all cases known female moths possess sex pheromone glands which apparently have been lost in female butterflies. In the day-flying moth family Castniidae ("butterfly-moths"), which includes some important crop pests, no pheromones have been found so far. Methodology/Principal Findings: Using a multidisciplinary approach we described the steps involved in the courtship of P. archon, showing that visual cues are the only ones used for mate location; showed that the morphology and fine structure of the antennae of this moth are strikingly similar to those of butterflies, with male sensilla apparently not suited to detect female-released long range pheromones; showed that its females lack pheromone-producing glands, and identified three compounds as putative male sex pheromone (MSP) components of P. archon, released from the proximal halves of male forewings and hindwings. Conclusions/Significance: This study provides evidence for the first time in Lepidoptera that females of a moth do not produce any pheromone to attract males, and that mate location is achieved only visually by patrolling males, which may release a pheromone at short distance, putatively a mixture of Z,E-farnesal, E,E-farnesal, and (E,Z)-2,13-octadecadienol. The outlined behavior, long thought to be unique to butterflies, is likely to be widespread in Castniidae implying a novel, unparalleled butterfly-like reproductive behavior in moths. This will also have practical implications in applied entomology since it signifies that the monitoring/control of castniid pests should not be based on the use of female-produced pheromones, as it is usually done in many moths.

Consequences of lineage-specific gene loss on functional evolution of surviving paralogs: ALDH1A and retinoic acid signaling in vertebrate genomes

Genome duplications increase genetic diversity and may facilitate the evolution of gene subfunctions. Little attention, however, has focused on the evolutionary impact of lineage-specific gene loss. Here, we show that identifying lineage-specific gene loss after genome duplication is important for understanding the evolution of gene subfunctions in surviving paralogs and for improving functional connectivity among human and model organism genomes. We examine the general principles of gene loss following duplication, coupled with expression analysis of the retinaldehyde dehydrogenase Aldh1a gene family during retinoic acid signaling in eye development as a case study. Humans have three ALDH1A genes, but teleosts have just one or two. We used comparative genomics and conserved syntenies to identify loss of ohnologs (paralogs derived from genome duplication) and to clarify uncertain phylogenies. Analysis showed that Aldh1a1 and Aldh1a2 form a clade that is sister to Aldh1a3-related genes. Genome comparisons showed secondarily loss of aldh1a1 in teleosts, revealing that Aldh1a1 is not a tetrapod innovation and that aldh1a3 was recently lost in medaka, making it the first known vertebrate with a single aldh1a gene. Interestingly, results revealed asymmetric distribution of surviving ohnologs between co-orthologous teleost chromosome segments, suggesting that local genome architecture can influence ohnolog survival. We propose a model that reconstructs the chromosomal history of the Aldh1a family in the ancestral vertebrate genome, coupled with the evolution of gene functions in surviving Aldh1a ohnologs after R1, R2, and R3 genome duplications. Results provide evidence for early subfunctionalization and late subfunction-partitioning and suggest a mechanistic model based on altered regulation leading to heterochronic gene expression to explain the acquisition or modification of subfunctions by surviving ohnologs that preserve unaltered ancestral developmental programs in the face of gene loss.

Job loss among immigrant and native workers: evidence from Spain's economic downturn

The profound crisis that has affected the Spanish economy since mid - 2008 has been characterized by significant job losses and a marked rise in the country´s unemployment rate. However, unemployment has had a differential impact on different population groups. Compared to native, immigrant workers have experienced higher rates of job loss. Against this backdrop, this paper examines the differences between immigrants and natives (distinguished by gender) in terms of their probability of suffering job loss in the downturn of late 2008 and 2009. Our results indicate that the higher rate of job loss among female immigrant workers can be fully explained by their lower endowment of human capital. By contrast, human capital endowment and over-representation in certain occupations, sectors and regions in which the crisis had greatest impact do not appear to be the only reason for the penalty suffered by immigrant males in terms of their chances of losing their job in the downturn.

Population connectivity buffers genetic diversity loss in a seabird

Background Ancient DNA has revolutionized conservation genetic studies as it allows monitoring of the genetic variability of species through time and predicting the impact of ecosystems" threats on future population dynamics and viability. Meanwhile, the consequences of anthropogenic activities and climate change to island faunas, particularly seabirds, remain largely unknown. In this study, we examined temporal changes in the genetic diversity of a threatened seabird, the Cory"s shearwater (Calonectris borealis). Findings We analysed the mitochondrial DNA control region of ancient bone samples from the late-Holocene retrieved from the Canary archipelago (NE Atlantic) together with modern DNA sequences representative of the entire breeding range of the species. Our results show high levels of ancient genetic diversity in the Canaries comparable to that of the extant population. The temporal haplotype network further revealed rare but recurrent long-distance dispersal between ocean basins. The Bayesian demographic analyses reveal both regional and local population size expansion events, and this is in spite of the demographic decline experienced by the species over the last millennia. Conclusions Our findings suggest that population connectivity of the species has acted as a buffer of genetic losses and illustrate the use of ancient DNA to uncover such cryptic genetic events.

Loss of intestinal epithelial barrier function in Salmonella Enteritidis infection

Intestinal infection with Salmonella enterica serotype Enteritidis, a food-borne infection spread to humans especially through contaminated eggs and egg-products as well as undercooked contaminated fresh meat, is the most common cause of intestinal inflammation in the European Union. Enteritis caused by Salmonella Enteritidis is characterized by fever, diarrhoea and abdominal pain. The disruption of the intestinal epithelial barrier function contributes to diarrhoea and is responsible for the perpetuation of the inflammatory process. In this sense, oxidative stress and the proinflammatory cytokines TNF-α, IFN-γ and IL-1β are described to induce the disorganization of the tight junctions (TJ), the most apical epithelial intercellular junctions and responsible for the paracellular permeability. The interest of this chapter relies not only in the investigation dealing with the mechanisms of TJ regulation but also in the contribution to the development of new tools for the prevention of epithelial barrier disruption in enteritis caused by Salmonella Enteritidis.

Green tea catechin inhibits fatty acid synthase without stimulating carnitine Palmitoyltransferase-1 or inducing weight loss in experimental animals

Background: The enzyme fatty acid synthase (FASN) is highly expressed in many human carcinomas and its inhibition is cytotoxic to human cancer cells. The use of FASN inhibitors has been limited until now by anorexia and weight loss, which is associated with the stimulation of fatty acid oxidation. Materials and Methods: The in vitro effect of (-)-epigallocatechin-3-gallate (EGCG) on fatty acid metabolism enzymes, on apoptosis and on cell signalling was evaluated. In vivo, the effect of EGCG on animal body weight was addressed. Results: EGCG inhibited FASN activity, induced apoptosis and caused a marked decrease of human epidermal growth factor receptor 2 (HER2), phosphatidylinositol 3-kinase (PI3K)/AKT and extracellular (signal)-regulated kinase (ERK) 1/2 proteins, in breast cancer cells. EGCG did not induce a stimulatory effect on CPT-1 activity in vitro (84% of control), or on animal body weight in vivo (99% of control). Conclusion: EGCG is a FASN inhibitor with anticancer activity which does not exhibit cross-activation of fatty acid oxidation and does not induce weight loss, suggesting its potential use as an anticancer drug.

Functional diversity of macrophyte communities within and between Pyrenean lakes

Submersed vegetation is a common feature in about 70% Pyrene an high mountain (>1500 m a.s.l.) lakes. Isoetids and soft-water elodeids are common elements of this underw ater flora and can form distinct vegetation units (i.e. patches of vegetation dominated by different species) within complex mosaics of vegetation in shallow waters (<7 m). Since is oetids exert a strong influence on sediment biogeochemistry due to high radial oxygen loss, we examined the small scale characteristics of the lake environment (water and sediment) associated to vegetation patches in order to ascertain potential functional differences among them. To do so, we characterised the species composition and biomass of the main vegetation units from 11 lakes, defined plant communities based on biomass data, and then related each community with sediment properties (redox and dissolved nutrient concentration in the pore water) and water nutrient concentration within plant canopy. We also characterised lake water and sediment in areas without vegetation as a reference. A total of twenty-one vegetation units were identified, ranging from one to five per lake. A cluster analysis on biomass species composition suggested seven different macrophyte communities that were named after the most dominant species:Nitella sp.,Potamogeton praelongus, Myriophyllum alterniflorum, Sparganium angustifolium , Isoetes echinospora,Isoetes lacustris and Carex rostrata . Coupling between macrophyte communities and their immediate environment (overlying water and sediment) was manifested mainly as variation in sediment redox conditions and the dominant form of inorganic nitrogen in pore-water. These effects depended on the specific compositi on of the community, and on the allocation between above- and belowground biomass, and could be predicted with a model relating the average and standard deviation of sediment redox potential from 0 down to -20 cm, across macrophyte communities. Differences in pore-water total dissolved phosphorus were related to the trophic state of the lakes. There was no correlation between sediment and water column dissolved nutrients. However, nitrate concentrations tended to be lower in the water overlaying isoetid communities, in apparent contradiction to the patterns of dissolved nitrates in the pore-water. These tendencies were robust even when comparing the water over laying communities within the same lake, thus pointing towards a potential effect of isoetids in reducing dissolved nitrogen in the lakes.

Fish colonization of artificial reefs in a large Neotropical reservoir: material type and successional changes

Artificial reefs have barely been used in Neotropical reservoirs (about five studies in three reservoirs), despite their potential as a fishery management tool to create new habitats and also to understand fish ecology. We experimentally assessed how reef material (ceramic, concrete, and PVC) and time modulated fish colonization of artificial reefs deployed in Itaipu Reservoir, a large reservoir of the mainstem Parana´ River, Brazil. Fish richness, abundance, and biomass were significantly greater in the reef treatments than at control sites. Among the experimental reefs, ceramic followed by the concrete treatments were the materials most effectively colonized, harboring the majority of the 13 fish species recorded. Although dependent on material type, many of the regularities of ecological successions were also observed in the artificial reefs, including decelerating increases in species richness, abundance, mean individual size, and species loss rates with time and decelerating decreases of species gain and turnover rates. Species composition also varied with material type and time, together with suites of life history traits: more equilibrium species (i.e., fishes of intermediate size that often exhibit parental care and produce fewer but larger offspring) of the Winemiller-Rose model of fish life histories prevailed in later successional stages. Overall, our study suggests that experimental reefs are a promising tool to understand ecological succession of fish assemblages, particularly in tropical ecosystems given their high species richness and low seasonality