The B1 shock in the L1157 outflow as seen at high spatial resolution

We present high spatial resolution (750 AU at 250 pc) maps of the B1 shock in the blue lobe of the L1157 outflow in four lines: CS (3-2), CH3OH (3_K-2_K), HC3N (16-15) and p-H2CO (2_02-3_01). The combined analysis of the morphology and spectral profiles has shown that the highest velocity gas is confined in a few compact (~ 5 arcsec) bullets while the lowest velocity gas traces the wall of the gas cavity excavated by the shock expansion. A large velocity gradient model applied to the CS (3-2) and (2-1) lines provides an upper limit of 10^6 cm^-3 to the averaged gas density in B1 and a range of 5x10^3< n(H2)< 5x10^5 cm^-3 for the density of the high velocity bullets. The origin of the bullets is still uncertain: they could be the result of local instabilities produced by the interaction of the jet with the ambient medium or could be clump already present in the ambient medium that are excited and accelerated by the expanding outflow. The column densities of the observed species can be reproduced qualitatively by the presence in B1 of a C-type shock and only models where the gas reaches temperatures of at least 4000 K can reproduce the observed HC3N column density.Comment: 13 pages, 12 figure

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

Fluorescent and Electroactive Monoalkyl BTD-Based Liquid Crystals with Tunable Self-Assembling and Electronic Properties

We report here on a series of redox active benzothiadiazole-based luminophores ffinctionalized on one edge with a phenyl-nonyl substituent, which confers these molecules a rodlike shape and a tendency to self-assemble into layered superstructures. On the other edge, the molecules are endowed with different p-substituted phenyl rings, which allows the modulation of their redox and optical properties on the basis of the electronic nature of the terminal substituents. We have found that just one lateral alkyl chain is sufficient to induce mesomorphism in these molecules, which present nematic or smectic mesophases upon therinal treatment. Single-crystal analysis allows us to get an insight into the nature of the forces responsible for different supramolecular assemblies in these derivatives, and point to a strong contribution of the terminal groups in the different arrangements observed. The interesting redox and optical properties together with their self-assembling tendencies render these new materials interesting candidates for optoelectromcs

Observation of a topologically protected state in a magnetic domain wall stabilized by a ferromagnetic chemical barrier

The precise control and stabilization of magnetic domain walls is key for the development of the next generation magnetic nano-devices. Among the multitude of magnetic configurations of a magnetic domain wall, topologically protected states are of particular interest due to their intrinsic stability. In this work, using XMCD-PEEM, we have observed a topologically protected magnetic domain wall in a ferromagnetic cylindrical nanowire. Its structure is stabilized by periodic sharp alterations of the chemical composition in the nanowire. The large stability of this topologically protected domain wall contrasts with the mobility of other non-protected and non-chiral states also present in the same nanowire. The micromagnetic simulations show the structure and the conditions required to find the topologically protected state. These results are relevant for the design of future spintronic devices such as domain wall based RF oscillators or magnetic memories

Quantum Loops in the Resonance Chiral Theory: The Vector Form Factor

We present a calculation of the Vector Form Factor at the next-to-leading order in the 1/N_C expansion, within the framework of Resonance Chiral Theory. The calculation is performed in the chiral limit, and with two dynamical quark flavours. The ultraviolet behaviour of quantum loops involving virtual resonance propagators is analyzed, together with the kind of counterterms needed in the renormalization procedure. Using the lowest-order equations of motion, we show that only a few combinations of local couplings appear in the final result. The low-energy limit of our calculation reproduces the standard Chiral Perturbation Theory formula, allowing us to determine the resonance contribution to the chiral low-energy couplings, at the next-to-leading order in 1/N_C, keeping a full control of their renormalization scale dependence.Comment: 27+1 pages, 9 figure

Pyridinethiolate titanocene metalloligands and their self-assembly reactions to yield early-late metallamacrocycles

New titanocene pyridinethiolate compounds [(RCp)(2)Ti(4-Spy)(2)] (R = H (1), Me (2); Cp = cyclo-pentadienyl; 4-Spy = pyridine-4-thiolate) and [Cp2Ti(2-Spy)(2)] (3; 2-Spy = pyridine-2-thiolate) have been prepared by reaction of the corresponding Li(Spy) salt with the appropriate compound [(RCp)(2)TiCl2]. Compounds 1 and 2 have been used as metalloligands in self-assembly reactions with the acceptor late-transition-metal compounds [M(H2O)(2)(dppp)]-(OTf)(2) (M = Pd (a) Pt (b); dppp = 1,3-bis-(diphenylphosphino)propane), and the series of early-late tetranuclear metallamacrocycles [{(RCp)(2)Ti(4-Spy)(2)}{M-(dppp)}](2)(OTf)(4) (R = H, M = Pd (1(2)a(2)); R = H, M = Pt (1(2)b(2)); R = Me, M = Pd (2(2)a(2)); R = Me, M = Pt (2(2)b(2))) arising from the anti isomer of the titanocene metalloligands have been obtained. Only ligand transfer reactions from Ti to either Pd or Pt atoms have been observed when the pyridine-2-thiolate derivative 3 has been assayed in self-assembly processes. The obtained species have been characterized by NMR spectroscopy and ESI(+) mass spectrometry. The supramolecular assemblies have shown to be nonrigid in solution, and their fluxional behavior has been studied by VT H-1 NMR spectroscopy. A DFT study including ab initio molecular dynamics in order to elucidate the structures and the relative stability of the isomers has been performed

Physical activity attenuates the effect of low birth weight on insulin resistance in adolescents: findings from two observational studies

OBJECTIVE: To examine whether physical activity influences the association between birth weight and insulin resistance in adolescents. RESEARCH DESIGN AND METHODS: The study comprised adolescents who participated in two cross-sectional studies: the Healthy Lifestyle in Europe by Nutrition in Adolescence (HELENA) study (n = 520, mean age = 14.6 years) and the Swedish part of the European Youth Heart Study (EYHS) (n = 269, mean age = 15.6 years). Participants had valid data on birth weight (parental recall), BMI, sexual maturation, maternal education, breastfeeding, physical activity (accelerometry, counts/minute), fasting glucose, and insulin. Insulin resistance was assessed by homeostasis model assessment-insulin resistance (HOMA-IR). Maternal education level and breastfeeding duration were reported by the mothers. RESULTS: There was a significant interaction of physical activity in the association between birth weight and HOMA-IR (logarithmically transformed) in both the HELENA study and the EYHS (P = 0.05 and P = 0.03, respectively), after adjusting for sex, age, sexual maturation, BMI, maternal education level, and breastfeeding duration. Stratified analyses by physical activity levels (below/above median) showed a borderline inverse association between birth weight and HOMA-IR in the low-active group (standardized β = -0.094, P = 0.09, and standardized β = -0.156, P = 0.06, for HELENA and EYHS, respectively), whereas no evidence of association was found in the high-active group (standardized β = -0.031, P = 0.62, and standardized β = 0.053, P = 0.55, for HELENA and EYHS, respectively). CONCLUSIONS: Higher levels of physical activity may attenuate the adverse effects of low birth weight on insulin sensitivity in adolescents. More observational data, from larger and more powerful studies, are required to test these findings.This work was mainly supported by the European Community Sixth RTD Framework Programme (Contract FOOD-CT-2005-007034) and by grants from the Stockholm County Council. This study was also supported by grants from the Spanish Ministry of Education (EX-2008-0641, AP2006-02464), the Swedish Heart-Lung Foundation (20090635), the Swedish Council for Working Life and Social Research (Forskningsrådet för arbetsliv och socialvetenskap [FAS]), the Spanish Ministry of Health: Maternal, Child Health and Development Network (Number RD08/0072), and the Spanish Ministry of Science and Innovation (RYC-2010-05957)

Associations between cardiorespiratory fitness, physical activity and clustered cardiometabolic risk in children and adolescents: the HAPPY study

Clustering of cardiometabolic risk factors can occur during childhood and predisposes individuals to cardiometabolic disease. This study calculated clustered cardiometabolic risk in 100 children and adolescents aged 10-14 years (59 girls) and explored differences according to cardiorespiratory fitness (CRF) levels and time spent at different physical activity (PA) intensities. CRF was determined using a maximal cycle ergometer test, and PA was assessed using accelerometry. A cardiometabolic risk score was computed as the sum of the standardised scores for waist circumference, blood pressure, total cholesterol/high-density lipoprotein ratio, triglycerides and glucose. Differences in clustered cardiometabolic risk between fit and unfit participants, according to previously proposed health-related threshold values, and between tertiles for PA subcomponents were assessed using ANCOVA. Clustered risk was significantly lower (p < 0.001) in the fit group (mean 1.21 ± 3.42) compared to the unfit group (mean -0.74 ± 2.22), while no differences existed between tertiles for any subcomponent of PA. Conclusion These findings suggest that CRF may have an important cardioprotective role in children and adolescents and highlights the importance of promoting CRF in youth

Coarse graining ππ scattering

We carry out an analysis of ππ scattering in the I J = 00, 11 and 20 channels in configuration space up to a maximal center-of-mass energy √ s = 1.4 GeV. We separate the interaction into two regions marked by an elementarity radius of the system; namely, a long distance region above which pions can be assumed to interact as elementary particles and a short distance region where many physical effects cannot be disentangled. The long distance interaction is described by chiral dynamics, where a two-pionexchange potential is identified, computed and compared to lattice calculations. The short distance piece corresponds to a coarse grained description exemplified by a superposition of delta-shell potentials sampling the interaction with the minimal wavelength. We show how the so constructed nonperturbative scattering amplitude complies with the proper analytic structure, allowing for an explicit N/D type decomposition in terms of the corresponding Jost functions and fulfilling dispersion relations without subtractions. We also address renormalization issues in coordinate space and investigate the role of crossing when fitting the scattering amplitudes above and below threshold to Roy-equation results. At higher energies, we show how inelasticities can be described by one single complex and energy dependent parameter. A successful description of the data can be achieved with a minimal number of fitting parameters, suggesting that coarse graining is a viable approach to analyze hadronic processes.Work partially supported by Spanish MINEICO and European FEDER funds (grants FIS2014-59386-P, FIS2017-85053-C2-1-P and FPA2015- 64041-C2-1-P), Junta de Andalucía (grant FQM-225) and the Swiss National Science Foundation