Liouville field theory coupled to a critical Ising model: Non-perturbative analysis, duality and applications

Two different kinds of interactions between a ${Z}_{n}$-parafermionic and a Liouville field theory are considered. For generic values of $n$, the effective central charges describing the UV behavior of both models are calculated in the Neveu-Schwarz sector. For $n=2$ exact vacuum expectation values of primary fields of the Liouville field theory, as well as the first descendent fields are proposed. For $n=1$, known results for Sinh-Gordon and Bullough-Dodd models are recovered whereas for $n=2$, exact results for these two integrable coupled Ising-Liouville models are shown to exchange under a weak-strong coupling duality relation. In particular, exact relations between the parameters in the actions and the mass of the particles are obtained. At specific imaginary values of the coupling and $n=2$, we use previous results to obtain exact information about: (a) Integrable coupled models like Ising-${\cal M}_{p/p'}$, homogeneous sine-Gordon model $SU(3)_2$ or the Ising-XY model; (b) Neveu-Schwarz sector of the $\Phi_{13}$ integrable perturbation of N=1 supersymmetric minimal models. Several non-perturbative checks are done, which support the exact results.Comment: 29 pages, 1 fig., LaTeX file with epsfig, amssymb, 3 references added. To appear in Nucl. Phys.

Variation in the ontogenetic allometry of horn length in bovids along a body mass continuum

Allometric relationships describe the proportional covariation between morphological, physiological, or life-history traits and the size of the organisms. Evolutionary allometries estimated among species are expected to result from species differences in ontogenetic allometry, but it remains uncertain whether ontogenetic allometric parameters and particularly the ontogenetic slope can evolve. In bovids, the nonlinear evolutionary allometry between horn length and body mass in males suggests systematic changes in ontogenetic allometry with increasing species body mass. To test this hypothesis, we estimated ontogenetic allometry between horn length and body mass in males and females of 19 bovid species ranging from ca. 5 to 700 kg. Ontogenetic allometry changed systematically with species body mass from steep ontogenetic allometries over a short period of horn growth in small species to shallow allometry with the growth period of horns matching the period of body mass increase in the largest species. Intermediate species displayed steep allometry over long period of horn growth. Females tended to display shallower ontogenetic allometry with longer horn growth compared to males, but these differences were weak and highly variable. These findings show that ontogenetic allometric slope evolved across species possibly as a response to size-related changes in the selection pressures acting on horn length and body mass.publishedVersio

Population genetics and forensic DNA for conservation management of the Cypriot mouflon (Ovis orientalis ophion)

The mouflon (Ovis orientalis ophion) is the largest wild terrestrial mammal of Cyprus. Considered as the flagship species of the island, its population (c. 3000 head) has a distribution range limited to the mountainous Paphos Forest and adjacent areas including parts of Troodos National Forest (> 700 Km2). The species is protected by a rigorous national legislation supported since 1996 by management plans carried out by the Game and Fauna Service, and, together with its habitat, by the National Law 152 (I)/2003 for the Protection & Management of Wild Birds and Game Species. The species is listed in the Annexes II and IV of 92/43 Habitats Directive, in the Appendix I of CITES, and classified as “vulnerable” by the IUCN. Poaching, habitat loss, road network building and livestock intrusion (i.e., increased risk of pathogen infection) represent the main threatening factors. We aimed at elucidating the systematic placement of the Cypriot mouflon to enforce its protection within an adaptive conservation framework. Therefore, we attempted to determine its genetic structure and relationships with either historically preserved (Corsica, Sardinia) or recently introduced (central Italy) populations including also GenBank entries from the historical range of the species (Near East). The Game and Fauna Service in collaboration with the Cyprus Veterinary Service collected 63 blood samples: 53 were from mouflons captured in the Paphos forest, eight from captive individuals and two of unknown origin. We also sampled 20 mouflons in Sardinia either in the wild (16) or in captivity (4), and collected scats of both Corsican (19) and central Italy (23: Tuscan Archipelago National Park, 13; Tuscan-Emilian Apennines National Park, 6; Apuan Alps Regional Park, 4) mouflon populations in order to increase geographical scope. We genotyped each sample at the entire mitochondrial DNA Cytochrome-b codifying gene (Cyt-b, 1140 bp) and up to 12 microsatellite DNA markers (Short Tandem Repeats, STR) isolated from goat, sheep and cattle genomes. We found that the Cypriot mouflon strongly diverged from western Mediterranean conspecifics, while North West Iran appeared as the most credited geographic region as the source for its ancient introduction to Cyprus. Although we disclosed much lower mitochondrial and nuclear DNA diversity in the Cypriot than in other island populations, neither evidence of genetic bottleneck nor significant low level of both average pairwise relatedness and inbreeding coefficient was detected. Overall, present mitochondrial and STR dataset worked reliably as crime-fighting tool to tackle illegal mouflon killing in Cyprus. Between 2008 and 2013, the Police and the Game and Fauna Service, in collaboration with the Cyprus Veterinary Services, confiscated 29 samples (meat, hairs, bloodstains) dealing with nine episodes of supposed poaching against the Cypriot mouflon. In all cases, we identified the species in point by sequencing the mtDNA Cyt-b gene. In one case, we were specifically requested to establish if there was a link between three dead mouflons recovered at a roadside and 12 bloodstains collected in the car of suspected poachers at the crime scene. With reference to this case, we were able to match nine bloodstains to two out of the three carcasses (seven with very strong support: Likelihood Ratio >3000 and Random Match Probability <10-3), overall assigning 22 out of 29 samples to the Cypriot mouflon and the remaining ones to wild boar, cow, domestic goat, horse and hare. These results included the first genetic reference for the Cypriot mouflon and the first published material of forensic wildlife investigations in Cyprus

Steep slopes, shallow angles; mountain ungulates create their own topography through movements

Travel is considered to account for a substantial proportion of endothermic species energy expenditure. However, transport costs depend on speed of the animal and slope angle of the terrain. We used biologging data from six ungulate species within the French mountains, combined with mapping data, to examine how these different species reacted to slopes by varying travel speed, and chosen ascent and descent angles, in relation to vectoral dynamic body acceleration (VeDBA; as a proxy for energy expenditure). As predicted by theory and as seen in pumas, animals travelled obliquely so that the angle that any individual experienced was lower than that of the topography. Travel speed affected the VeDBA-based proxy for Cost Of Transport (COT) even though most species moved slower on steeper inclines. Models that considered speed, COT, slope and habitat type showed clear relationships between COT and slope with variation across habitat types and according to species. Species-specific choice of travel speeds and ACS underpins fundamental differences in species physiology and ecology via links in heat production and time spent per altitude. Understanding these interrelations points to the complexity of factors affecting space use by mountain ungulates and is crucial for conservation efforts, especially in fast-changing environments where energy expenditure, temperature changes and resource accessibility impact population wellbeing.The presentation of the authors' names and (or) special characters in the title of the pdf file of the accepted manuscript may differ slightly from what is displayed on the item page. The information in the pdf file of the accepted manuscript reflects the original submission by the author

Near infrared reflectance spectroscopy analysis to predict diet composition of a mountain ungulate species

The diet composition of ungulates is important to understand not only their impact on vegetation, but also to understand the consequences of natural and human-driven environmental changes on the foraging behavior of these mammals. In this work, we evaluated the use of near infrared reflectance spectroscopy analysis (NIRS), a quick, economic and non-destructive method, to assess the diet composition of the Pyrenean chamois Rupicapra pyrenaica pyrenaica. Fecal samples (n = 192) were collected from two chamois populations in the French and Spanish Pyrenees. Diet composition was initially assessed by fecal cuticle microhistological analysis (CMA) and categorized into four functional groups, namely: woody, herbaceous, graminoid and Fabaceae plants. Regressions of modified partial least squares and several combinations of scattering correction and derivative treatments were tested. The results showed that models based on the second derivative processing obtained the higher determination coefficient for woody, herbaceous and graminoid plants (RCAL, coefficient of determination in calibration, ranged from 0.86 to 0.91). The Fabaceae group, however, was predicted with lower accuracy (RCAL = 0.71). Even though an agreement between NIRS and CMA methods was confirmed by a Bland-Altman analysis, confidence limits of agreement differed by up to 25%. Our results support the viability of fecal NIRS analysis to study spatial and temporal variations of the Pyrenean chamois' diets in summer and winter when differences in the consumption of woody and annual plants are the greatest. This new use for the NIRS technique would be useful to assess the consequences of global change on the feeding behavior of this mountain ungulate and also in other ungulate counterparts

Variation in the ontogenetic allometry of horn length in bovids along a body mass continuum

International audienceAllometric relationships describe patterns of proportional covariation between morphological, physiological, or life-history traits and the size of the organisms among populations or species (evolutionary allometry), or within population, among individuals measured at similar (static allometry), or different (ontogenetic allometry) age or developmental stages. When expressed on a log-log scale, allometric relationships are often described by a linear regression: log(y) = a + b log(x) where y is the trait size; x the body size; and a and b the allometric intercept and slope, respectively (Huxley, 1932). Because population and species mean trait size and body size used to estimate evolutionary allometry result from the proportional growth of both traits, patterns of evolutionary allometry emerge from variation in ontogenetic allom

Predicting LyC emission of galaxies using their physical and Lyα\alpha emission properties

The primary difficulty in understanding the sources and processes that powered cosmic reionization is that it is not possible to directly probe the ionizing Lyman Continuum (LyC) radiation at that epoch as those photons have been absorbed by the intervening neutral hydrogen in the IGM on their way to us. It is therefore imperative to build a model to accurately predict LyC emission using other properties of galaxies in the reionization era. In recent years, studies have shown that the LyC emission from galaxies may be correlated to their Lya emission. Here, we study this correlation by analyzing thousands of galaxies at high-z in the SPHINX cosmological simulation. We post-process these galaxies with the Lya radiative transfer code RASCAS and analyze the Lya - LyC connection. We find that the Lya and LyC luminosities are strongly correlated with each other, although with dispersion. There is a positive correlation between Lya and LyC escape fractions in the brightest Lya emitters (>$10^{41}$ erg/s), similar to the recent observational studies. However, when we also include fainter Lya emitters (LAEs), the correlation disappears, which suggests that the observed relationship may be driven by selection effects. We also find that bright LAEs are dominant contributors to reionization ($> 10^{40}$ erg/s galaxies contribute $> 90\%$ of LyC emission). Finally, we build predictive models using multivariate linear regression where we use the physical and the Lya properties of simulated galaxies to predict their intrinsic and escaping LyC luminosities with a high degree of accuracy. We find that the most important galaxy properties to predict the escaping LyC luminosity of a galaxy are its escaping Lya luminosity, gas mass, gas metallicity, and SFR. These models can be very useful to predict LyC emissions from galaxies and can help us identify the sources of reionization.Comment: Accepted to Astronomy and Astrophysics (A&A) Journal. 27 pages, 21 Figure

Predicting fiber content in herbivore fecal samples using a multispecies NIRS model

Fiber is essential for rumen health, microbial fermentation, and the energy supply of herbivores. Even though the study of fecal fiber contents (neutral detergent fiber NDF, acid detergent fiber ADF, and acid detergent lignin ADL) using near-infrared reflectance spectroscopy (NIRS) has allowed investigating nutritional ecology of different herbivore species, NIRS calibrations are species-specific and require a large number of samples for predictions. A multispecies calibration would be an advantage since samples from different herbivores could be used to calibrate a model capable of predicting the fecal fiber content of other herbivores. To date, however, multispecies models have not been developed to predict fiber contents in the feces of herbivores. Here, we fill this gap by calibrating three fiber multispecies models (NDF, ADF and ADL) using fecal samples from domestic and wild herbivore species. We also evaluated the effect of incorporating sodium sulfite in fiber determination protocol. The initial dataset consisting of 445 samples of six herbivore species was used to calibrate (80% of the samples) and validate (20% of the samples) the models. Subsequently, 63 samples of five herbivores not included in the calibration set were used for the external validation of the model. Since sodium sulfite did not significantly improve fecal fiber prediction, our model was developed without this compound. The multispecies models obtained were highly accurate determining NDF, ADF and ADL (R2CAL, coefficient of determination in calibration, ≥ 0.93, R2VAL, coefficient of determination in validation, ≥ 0.91) and independent of external confounders. For external validation, the accuracy in predicting fecal samples in other herbivore species was also satisfactory, with consistently better values for NDF (R2VAL, 0.86–0.94) and ADF (R2VAL, 0.80–0.95) than for ADL (R2VAL, 0.66–0.89). We show that multispecies NIRS calibrations can be used with high accuracy to assess fecal fiber contents across diverse herbivore species. This finding represents a significant advance in the study of the nutritional ecology of herbivores with contrasting foraging patterns. In the future, widening the data range (e.g., species and locations) of the initial dataset could further improve the accuracy of these models