Evidence of ongoing radial migration in NGC 6754: Azimuthal variations of the gas properties

Understanding the nature of spiral structure in disk galaxies is one of the main, and still unsolved questions in galactic astronomy. However, theoretical works are proposing new testable predictions whose detection is becoming feasible with recent development in instrumentation. In particular, streaming motions along spiral arms are expected to induce azimuthal variations in the chemical composition of a galaxy at a given galactic radius. In this letter we analyse the gas content in NGC 6754 with VLT/MUSE data to characterise its 2D chemical composition and H$\alpha$ line-of-sight velocity distribution. We find that the trailing (leading) edge of the NGC 6754 spiral arms show signatures of tangentially-slower, radially-outward (tangentially-faster, radially-inward) streaming motions of metal-rich (poor) gas over a large range of radii. These results show direct evidence of gas radial migration for the first time. We compare our results with the gas behaviour in a $N$-body disk simulation showing spiral morphological features rotating with a similar speed as the gas at every radius, in good agreement with the observed trend. This indicates that the spiral arm features in NGC 6754 may be transient and rotate similarly as the gas does at a large range of radii.Comment: 8 pages, 4 figures, accepted for publication in ApJL 2016 September 2

Differences in the leaf functional traits of six beech (Fagus sylvatica L.) populations are reflected in their response to water limitation

Patterns of intraspecific variation in functional traits have been widely studied across plant species to find out what general suites of traits provide functional advantage under specific environmental conditions. Much less is known about this variation within tree species and, in particular, about its relationship with performance variables such as photosynthetic rates under water deficit. Nevertheless, this knowledge is fundamental to understand the adaptive potential of drought sensitive tree species to increased aridity as predicted in the context of climate change. Intraspecific variation in photosynthetic performance and other leaf functional traits in response to water availability were examined in a glasshouse experiment using seedlings of six European beech populations. The physiological response of seedlings to a “water stress” treatment was compared to a “control” treatment along an experimental cycle of progressive soil water deficit and recovery. We found evidence of intraspecific variation in beech's photosynthetic performance and other leaf functional traits in response to water availability. We also detected intraspecific variation in leaf-level tolerance of water deficit and phenotypic plasticity to water availability suggesting a pattern shaped by both regional and local scale effects. The Swedish population was particularly sensitive to water deficit, being the only population showing impaired photochemical efficiency under the experimental water deficit. Leaf-level tolerance of water deficit was related to PNUE, but not to other functional traits, such as WUE, SLA or leaf nitrogen content, that have been described to vary across species in adaptation to drought tolerance. Our results support the idea that general trends for variation in functional traits across species do not necessarily reflect a similar pattern when observed at the intraspecific level. The observed functional variation between beech populations reaffirms the importance of local adaptation to water deficit in the context of climate changePeer ReviewedClimate changeGas exchangeIntraspecific variabilityNitrogen contentPhotochemical efficiencyPhotosynthesisSpecific leaf areaStomatal conductanceWater-use efficiencyWater stressPublishe

Virtual reality training platform for flexible ureterorenoscopy interventions with a minimally invasive surgical robot

The total number of ureteroscopy (URS) interventions during the past years has dramatically increased due to the ongoing technological advances and the benefits associated with these techniques. However, the current URS procedure presents some drawbacks to urologic surgeons. The LITHOS project was created with the main objective of developing a surgical robotic system for flexible ureterorenoscopic lithotripsy interventions, offering a technological solution that meets the real needs of both patients and surgeons in this type of procedures. In this paper, a virtual reality environment for flexible ureterorenoscopy interventions is presented. The proposed environment provides a suitable training platform for surgeons manipulating the surgical robotic system

Analog CMOS Readout Channel for Time and Amplitude Measurements With Radiation Sensitivity Analysis for Gain-Boosting Amplifiers

The front-end readout channel consists of a charge sensitive amplifier (CSA) and two different unipolar-shaping circuits to generate pulses suitable for time and energy measurement. The signal processing chain of the single channel is built of two different parallel processing paths: a fast path with a peaking time of 30 ns to obtain the time of arrival for each particle impinging the detector; and a slow path with a peaking time of 400 ns dedicated for low noise amplitude measurements, which is formed by a pole-zero cancellation circuit and a 4th order complex shaper based on a bridged-T architecture. The tunability of the system is accomplished by the discharge time constant of the CSA in order to accommodate various event rates. The readout system has been implemented in a 180 nm CMOS technology with the size of 525 μm x 290 μm . The building blocks use compact gain-boosting techniques based on quasi-floating gate (QFG) transistors achieving accurate energy measurement with good resolution. The high impedance nodes of QFG transistors require a detailed study of sensitivity to single-effect transients (SET). After carrying out this study, this paper proposes a method to select the value of the QFG capacitors, minimizing the area occupancy while maintaining robustness to radiation. The nonlinearity of the CSA-slow-shaper has been found to be less than 1% over a 10–70 fC input charge. The power dissipation of the readout channel is 4.1 mW with a supply voltage of 1.8 V.Ministerio de Ciencia, Innovación y Universidades PGC2018-095640-B-I00Consejería de Transformación Económica, Industria, Conocimiento y Universidades P18-FR-3852 y P18-FR-431

Utilizing volatile organic compounds for early detection of Fusarium circinatum

Acknowledgements This study was financially supported by The Swedish Research Council Formas, Grant #2018-00966, Crafoordska stiftelsen Grant #20200631, Carl Tryggers Stiftelse för Vetenskaplig Forskning Grant 18:67, The Royal Swedish Academy of Agriculture and Forestry, Stiftelsen fonden för skogsvetenskaplig forskning, Erasmus+ Staff mobility grant, Anna-Britta & Vadim Söderströms resestipendium and NordGen Forest SNS scholarships. J.N.S. was supported by The European Union’s Horizon Europe research and innovation programme under the MSCA agreement No 101068728. Thanks to dr. R.R. Vetukuri for providing F. graminearum, to the staff of Laboratorio de Técnicas Instrumentales, Universidad de Valladolid, for providing access to lab facilities and to J-E. Englund for assistance in making the experimental design. Funding Open access funding provided by Swedish University of Agricultural Sciences.Peer reviewedPublisher PD

Static behavior of CFRPs at low temperatures

8 pages, 11 figures.This paper summarizes the results of the tests to determine the effect of the low temperature on the mechanical behavior of carbon fiber reinforced epoxy laminates. Tensile and bending static tests were carried out on two laminate lay-ups (quasi-isotropic and cross-ply laminates), determining properties such as the mechanical strength, stiffness and strain to failure. The results show the changes in the mechanical behavior of this material at different test temperatures (20, −60 and −150 °C).The authors are indebted to the Spanish Comisión Interministerial de Ciencia y Tecnología (Project MAT 98/0273) for the financial support of this work.Publicad

Metric competencies for biomedical librarians: results of a survey developed by the EAHIL Evaluation and Metrics group

The library profession continues to evolve and respond to user demands with both tools and services that support instruction and research. These changes typically lead to a need for increased librarian understanding and training. One such example is seen in the growing interest surrounding bibliometrics, altmetrics, and personal identifiers. Each of these serve as indicators of impact, and are becoming increasingly important in research. To more clearly identify and measure the current prevalence of each in the librarian profession, the EAHIL Metrics Group developed and disseminated a survey designed to capture current demand, and identify potential knowledge gaps where training would be beneficial. This publication presents the results of the survey and discusses pathways to attaining and providing increased expertise

Characterization of EEG patterns in brain-injured subjects and controls after a Snoezelen® intervention

Producción CientíficaBackground and objective. The aim of this study was to assess the changes induced in electroencephalographic (EEG) activity by a Snoezelen® intervention on individuals with brain-injury and control subjects. Methods: EEG activity was recorded preceding and following a Snoezelen® session in 18 people with cerebral palsy (CP), 18 subjects who have sustained traumatic brain-injury (TBI) and 18 controls. EEG data were analyzed by means of spectral and nonlinear measures: median frequency (MF), individual alpha frequency (IAF), sample entropy (SampEn) and Lempel-Ziv complexity (LZC). Results: Our results showed decreased values for MF, IAF, SampEn and LZC as a consequence of the therapy. The main changes between pre-stimulation and post-stimulation conditions were found in occipital and parietal brain areas. Additionally, these changes are more widespread in controls than in brain-injured subjects, which can be due to cognitive deficits in TBI and CP groups. Conclusions: Our findings support the notion that Snoezelen® therapy affects central nervous system, inducing a slowing of oscillatory activity, as well as a decrease of EEG complexity and irregularity. These alterations seem to be related with higher levels of relaxation of the participants.Ministerio de Economía y Competitividad (TEC2014-53196-R)Junta de Castilla y León (VA059U13 y BIO/VA08/15

The local and global relations between Σ⋆\Sigma_\star , ΣSFR\Sigma_{\rm SFR} and Σmol\Sigma_{\rm mol} that regulate star-formation

Star-formation is one of the main processes that shape galaxies, defining its stellar population and metallicity production and enrichment. It is nowadays known that this process is ruled by a set of relations that connect three parameters: the molecular gas mass, the stellar mass and the star-formation rate itself. These relations are fulfilled at a wide range of scales in galaxies, from galaxy wide to kpc-scales. At which scales they are broken, and how universal they are (i.e., if they change at different scales or for different galaxy types) it is still an open question. We explore here how those relations compare at different scales using as proxy the new analysis done using Integral Field Spectroscopy data and CO observations data from the EDGE-CALIFA survey and the AMUSSING++ compilation.Comment: 8 pages, 3 figures, 1 table, proceedings of the IAU Symposium 373: Resolving the Rise and Fall of Star Formation in Galaxie