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.

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.

Architectural characterization of a delta-front reservoir analogue combining ground penetrating radar and electrical resistivity tomography: Roda Sandstone (Lower Eocene, Graus-Tremp basin, Spain)

Three-dimensional reconstruction of reservoir analogues can be improved combining data from different geophysical methods. Ground Penetrating Radar (GPR) and Electrical Resistivity Tomography (ERT) data are valuable tools, since they provide subsurface information from internal architecture and facies distribution of sedimentary rock bodies, enabling the upgrading of depositional models and heterogeneity reconstruction. The Lower Eocene Roda Sandstone is a well-known deltaic complex widely studied as a reservoir analogue that displays a series of sandstone wedges with a general NE to SW progradational trend. To provide a better understanding of internal heterogeneity of a 10m-thick progradational delta-front sandstone unit, 3D GPR data were acquired. In addition, common midpoints (CMP) to measure the sandstone subsoil velocity, test profiles with different frequency antennas (25, 50 and 100MHz) and topographic data for subsequent correction in the geophysical data were also obtained. Three ERT profiles were also acquired to further constrain GPR analysis. These geophysical results illustrate the geometry of reservoir analogue heterogeneities both depositional and diagenetic in nature, improving and complementing previous outcrop-derived data. GPR interpretation using radar stratigraphy principles and attributes analysis provided: 1)tridimensional geometry of major stratigraphic surfaces that define four units in the GPR Prism, 2) image the internal architecture of the units and their statistical study of azimuth and dips, useful for a quick determination of paleocurrent directions. These results were used to define the depositional architecture of the progradational sandbody that shows an arrangement in very-high-frequency sequences characterized by clockwise paleocurrent variations and decrease of the sedimentary flow, similar to those observed at a greater scale in the same system. This high-frequency sequential arrangement has been attributed to the autocyclic dynamics of a supply-dominated delta- front where fluvial and tidal currents are in competition. The resistivity models enhanced the viewing of reservoir quality associated with cement distribution caused by depositional and early diagenetic processes related to the development of transgressive and regressive systems tracts in igh-frequency sequences.

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.

Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy

Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.

Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy

Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.

Design concepts for the Cherenkov Telescope Array CTA: an advanced facility for ground-based high-energy gamma-ray astronomy

Ground-based gamma-ray astronomy has had a major breakthrough with the impressive results obtained using systems of imaging atmospheric Cherenkov telescopes. Ground-based gamma-ray astronomy has a huge potential in astrophysics, particle physics and cosmology. CTA is an international initiative to build the next generation instrument, with a factor of 5-10 improvement in sensitivity in the 100 GeV-10 TeV range and the extension to energies well below 100 GeV and above 100 TeV. CTA will consist of two arrays (one in the north, one in the south) for full sky coverage and will be operated as open observatory. The design of CTA is based on currently available technology. This document reports on the status and presents the major design concepts of CTA.

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.

Invasive species and habitat degradation in Iberian streams: an analysis of their role in freshwater fish diversity loss

Mediterranean endemic freshwater fish are among the most threatened biota in the world. Distinguishing the role of different extinction drivers and their potential interactions is crucial for achieving conservation goals. While some authors argue that invasive species are a main driver of native species declines, others see their proliferation as a co-occurring process to biodiversity loss driven by habitat degradation. It is difficult to discern between the two potential causes given that few invaded ecosystems are free from habitat degradation, and that both factors may interact in different ways. Here we analyze the relative importance of habitat degradation and invasive species in the decline of native fish assemblages in the Guadiana River basin (southwestern Iberian Peninsula) using an information theoretic approach to evaluate interaction pathways between invasive species and habitat degradation (structural equation modeling, SEM). We also tested the possible changes in the functional relationships between invasive and native species, measured as the per capita effect of invasive species, using ANCOVA. We found that the abundance of invasive species was the best single predictor of natives’ decline and had the highest Akaike weight among the set of predictor variables examined. Habitat degradation neither played an active role nor influenced the per capita effect of invasive species on natives. Our analyses indicated that downstream reaches and areas close to reservoirs had the most invaded fish assemblages, independently of their habitat degradation status. The proliferation of invasive species poses a strong threat to the persistence of native assemblages in highly fluctuating environments. Therefore, conservation efforts to reduce native freshwater fish diversity loss in Mediterranean rivers should focus on mitigating the effect of invasive species and preventing future invasions

A Method for Sky-Condition Classification from Ground-Based Solar Radiation Measurements

Identification of clouds from satellite images is now a routine task. Observation of clouds from the ground, however, is still needed to acquire a complete description of cloud conditions. Among the standard meteorologicalvariables, solar radiation is the most affected by cloud cover. In this note, a method for using global and diffuse solar radiation data to classify sky conditions into several classes is suggested. A classical maximum-likelihood method is applied for clustering data. The method is applied to a series of four years of solar radiation data and human cloud observations at a site in Catalonia, Spain. With these data, the accuracy of the solar radiation method as compared with human observations is 45% when nine classes of sky conditions are to be distinguished, and it grows significantly to almost 60% when samples are classified in only five different classes. Most errors are explained by limitations in the database; therefore, further work is under way with a more suitable database