Numerical study of barriers and valleys in the free-energy landscape of spin glasses

We study the problem of glassy relaxations in the presence of an external field in the highly controlled context of a spin-glass simulation. We consider a small spin glass in three dimensions (specifically, a lattice of size L=8, small enough to be equilibrated through a Parallel Tempering simulations at low temperatures, deep in the spin glass phase). After equilibrating the sample, an external field is switched on, and the subsequent dynamics is studied. The field turns out to reduce the relaxation time, but huge statistical fluctuations are found when different samples are compared. After taking care of these fluctuations we find that the expected linear regime is very narrow. Nevertheless, when regarded as a purely numerical method, we find that the external field is extremely effective in reducing the relaxation times.Comment: 22 pages, 10 figures; Published versio

¿Son el bajo nivel de condición física y la obesidad dos características del adolescente con síndrome de Down?

Introduction: “Obesity” is considered a feature of youth with DS but whether “low physical fitness” is also a feature is unknown. Objective: The aim of this case-control study was to compare the levels of fatness and fitness in adolescents with and without DS. Methods: Participants included 17 (5 girls) adolescents with DS aged 12-18 years and a control group of 94 (45 girls) adolescents without DS aged 12-16 years. The ALPHA health-related fitness test battery for children and adolescents was selected to assess fatness and fitness in both groups. Results: There were no differences in levels of fatness between groups (all P > 0.27). Adolescents with DS had lower levels of fitness in all the tests than adolescents without DS (all P < 0.001). Conclusion: Adolescents with DS have similar levels of fatness and lower levels of fitness than their peers without DSIntroducción: La obesidad es considerada una característica de los jóvenes con SD, sin embargo se desconoce si la “baja condición física” también lo es. Objetivo: Comparar los niveles de obesidad y condición física en adolescentes con y sin SD. Métodos: Participaron 17 adolescentes (5 niñas) con SD de 12 a 18 años y un grupo control de 94 (45 niñas) adolescentes sin SD de 12-16 años de edad. La batería de condición física ALPHA relacionada con la salud para niños y adolescentes fue seleccionada para evaluar la obesidad y la condición física en ambos grupos. Resultados: No se encontraron diferencias en los niveles de obesidad entre grupos (P > 0,27). Los adolescentes con SD tuvieron niveles más bajos de condición física en todos los test en comparación con los adolescentes sin SD (P < 0,001). Conclusión: Los adolescentes con SD tienen niveles similares de obesidad y menores de condición física que sus compañeros sin SD.The UP&DOWN study was supported by the Spanish Ministry of Economy and Competitiveness (DEP 2010-21662-C04). JRR was supported by a contract from the Spanish Ministry of Science and Innovation (RYC-2010-05957

Early Science with the Large Millimeter Telescope: an energy-driven wind revealed by massive molecular and fast X-ray outflows in the Seyfert Galaxy IRAS 17020+4544

We report on the coexistence of powerful gas outflows observed in millimeter and X-ray data of the Radio-Loud Narrow Line Seyfert 1 Galaxy IRAS 17020+4544. Thanks to the large collecting power of the Large Millimeter Telescope, a prominent line arising from the 12CO(1-0) transition was revealed in recent observations of this source. The complex profile is composed by a narrow double-peak line and a broad wing. While the double-peak structure may be arising in a disk of molecular material, the broad wing is interpreted as the signature of a massive outflow of molecular gas with an approximate bulk velocity of -660 km/s. This molecular wind is likely associated to a multi-component X-ray Ultra-Fast Outflow with velocities reaching up to ~0.1c and column densities in the range 10^{21-23.9} cm^-2 that was reported in the source prior to the LMT observations. The momentum load estimated in the two gas phases indicates that within the observational uncertainties the outflow is consistent with being propagating through the galaxy and sweeping up the gas while conserving its energy. This scenario, which has been often postulated as a viable mechanism of how AGN feedback takes place, has so far been observed only in ULIRGs sources. IRAS 17020+4544 with bolometric and infrared luminosity respectively of 5X10^{44} erg/s and 1.05X10^{11} L_sun appears to be an example of AGN feedback in a NLSy1 Galaxy (a low power AGN). New proprietary multi-wavelength data recently obtained on this source will allow us to corroborate the proposed hypothesis.Comment: Accepted for publication on ApJ Letters, 9 pages, 4 figure

NICMOS Imaging of Molecular Hydrogen Emission in Seyfert Galaxies

We present NICMOS imaging of broad band and molecular hydrogen emission in Seyfert galaxies. In 6 of 10 Seyferts we detect resolved or extended emission in the 1-0 S(1) 2.121 or 1-0 S(3) 1.9570 micron molecular hydrogen lines. We did not detect emission in the most distant galaxy or in the 2 Seyfert 1 galaxies in our sample because of the luminosity of the nuclear point sources. In NGC 5643, NGC 2110 and MKN 1066, molecular hydrogen emission is detected in the extended narrow line region on scales of a few hundred pc from the nucleus. Emission is coincident with [OIII] and H alpha+[NII] line emission. This emission is also near dust lanes observed in the visible to near-infrared color maps suggesting that a multiphase medium exists near the ionization cones and that the morphology of the line emission is dependent on the density of the ambient media. The high 1-0 S(1) or S(3) H2 to H alpha flux ratio suggests that shock excitation of molecular hydrogen (rather than UV fluorescence) is the dominant excitation process in these extended features. In NGC 2992 and NGC 3227 the molecular hydrogen emission is from 800 and 100 pc diameter `disks' (respectively) which are not directly associated with [OIII] emission and are near high levels of extinction (AV > 10). In NGC 4945 the molecular hydrogen emission appears to be from the edge of a 100 pc superbubble. In these 3 galaxies the molecular gas could be excited by processes associated with local star formation. We confirm previous spectroscopic studies finding that no single mechanism is likely to be responsible for the molecular hydrogen excitation in Seyfert galaxies.Comment: submitted to Ap

The influence of road networks on brown bear spatial distribution and habitat suitability in a human-modified landscape

Roads are human infrastructure that heavily affect wildlife, often with marked impacts on carnivores, including brown bears Ursus arctos. Here, we assessed the potential impact of road networks on the distribution of brown bears in the small, isolated and endangered Cantabrian population of north-western Spain. To ascertain whether local road networks affect brown bear spatial distribution, we first assessed potential influences on the distance of bear locations to roads using candidate models which included topographic variables, landcover types, bear age and reproductive status, traffic volume and road visibility. Then, we built two sets of habitat suitability models, both with and without roads, to discern the possible loss of habitat suitability caused by roads. The mean distance of bear locations to the nearest road was 968 804 m and the closest road was a low traffic road in 72.5% of cases. Candidate models showed little influence of our variables on bear distance to the nearest road, with the exception of elevation. Habitat suitability models revealed that road networks in our study area seem to have almost no effect on brown bear habitat suitability, except for females with yearlings during the denning season. However, this result may also be a consequence of the fact that only a small proportion (16.5%) of the cells classified as suitable bear habitats were crossed by roads, that is, most of the roads are primarily located in unsuitable bear habitats in the Cantabrian Mountains. Compared to previous studies conducted in other populations, mainly North American ones, our findings might suggest a different response of Eurasian brown bears to roads due to a longer bear-human coexistence in Europe versus North America. However, the indirect approach used in our study does not exclude other detrimental effects, for example, road mortality, increased stress and movement pattern disruption, only detectable by more direct approaches such as telemetry

Monounsaturated fatty acids, olive oil and blood pressure: epidemiological, clinical and experimental evidence

Diet has an important role in the prevention and treatment of hypertension. In early epidemiological studies, conducted mainly in the USA, monounsaturated fatty acids showed a deleterious association with blood pressure or no relationship at all. However, more recent studies, conducted in Mediterranean countries, have shed new light on this issue. In the present review we summarise the main results of epidemiological studies and feeding trials, and explain the possible mechanisms through which monounsaturated fatty acids, and specifically olive oil as the major dietary source of this type of fat in Mediterranean countries, could exert a favourable effect on blood pressure

Novel Graphical Analyses of Runs of Homozygosity among Species and Livestock Breeds

peer-reviewedRuns of homozygosity (ROH), uninterrupted stretches of homozygous genotypes resulting from parents transmitting identical haplotypes to their offspring, have emerged as informative genome-wide estimates of autozygosity (inbreeding). We used genomic profiles based on 698 K single nucleotide polymorphisms (SNPs) from nine breeds of domestic cattle (Bos taurus) and the European bison (Bison bonasus) to investigate how ROH distributions can be compared within and among species. We focused on two length classes: 0.5–15 Mb to investigate ancient events and >15 Mb to address recent events (approximately three generations). For each length class, we chose a few chromosomes with a high number of ROH, calculated the percentage of times a SNP appeared in a ROH, and plotted the results. We selected areas with distinct patterns including regions where (1) all groups revealed an increase or decrease of ROH, (2) bison differed from cattle, (3) one cattle breed or groups of breeds differed (e.g., dairy versus meat cattle). Examination of these regions in the cattle genome showed genes potentially important for natural and human-induced selection, concerning, for example, meat and milk quality, metabolism, growth, and immune function. The comparative methodology presented here permits visual identification of regions of interest for selection, breeding programs, and conservation.Cino Pertoldi was supported by a grant from Danish Natural Science Research Council (Grant nos. 11-103926, 09-065999, and 95095995), the Carlsberg Foundation (Grant no. 2011- 01-0059), and the Aalborg Zoo Conservation Foundation (AZCF). Laura Iacolina has received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie Action (Grant Agreement no. 656697). Astrid V. Stronen received funding from the Danish Natural Science Research Council (Postdoctoral Grant 1337-00007)

Correlates of ideal cardiovascular health in European adolescents: The HELENA study

Background and aims: The ideal cardiovascular health (iCVH) construct consists of 4 health behaviors (smoking status, body mass index, physical activity and diet) and 3 health factors (total cholesterol, blood pressure and fasting glucose). A greater number of iCVH components in adolescence are related to better cardiovascular health, but little is known about the correlates of iCVH in adolescents. Thus, the aim of the study was to examine correlates of iCVH in European adolescents. Methods and results: The study comprised 637 European adolescents with complete iCVH data. Participants were part of the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study, a cross-sectional, multicenter study conducted in 9 different European countries. Correlates investigated were sex and age, family affluence scale, maternal education, geographic location, sleep time, television viewing, duration of pregnancy, birth weight and breastfeeding. Younger adolescents, those whose mothers had medium/high education or those whowatched television less than 2 h per day had a greater number of iCVH components compared to those who were older, had a mother with low education or watched television 2 h or more daily (P <= 0.01). Conclusion: Since in our study older adolescents had worse iCVH than younger adolescents, early promotion of cardiovascular health may be important. Future studies mayalso investigate the usefulness of limiting television viewing to promote iCVH. Finally, since adolescents of mothers with low education had poorer iCVH, it may be of special interest to tailor public health promotion to adolescents from families with low socioeconomic status