bluuebunny/crossref_metadata_2025_split huggingface dataset:
Plasticity in host utilization by two host-associated populations ofAphis gossypiiGlover
Authors: Barman A.K. , Gadhave K.R. , Dutta B. , Srinivasan R. 
Published: September 2017

AbstractBiological and morphological plasticity in polyphagous insect herbivores allow them to exploit diverse host plant species. Geographical differences in resource availability can lead to preferential host exploitation and result in inconsistent host specialization. Biological and molecular data provide insights into specialization and plasticity of such herbivore populations. In agricultural landscapes,Aphis gossypiiencounters several crop and non-crop hosts, which exist in temporal and spatial proximity. We investigated the host-specialization of twoA. gossypiihost-associated populations (HAPs), which were field collected from cotton and squash (cotton-associated population and melon-associated population), and later maintained separately in the greenhouse. The two aphid populations were exposed to seven plant species (cotton, okra, watermelon, squash, cucumber, pigweed, and morning glory), and evaluated for their host utilization plasticity by estimating aphid's fitness parameters (nymphal period, adult period, fecundity, and intrinsic rate of increase). Four phenotypical characters (body length, head capsule width, hind tibia length and cornicle length) were also measured from the resulting 14 different HAP × host plant combinations. Phylogenetic analysis of mitochondrial COI sequences showed no genetic variation between the two HAPs. Fitness parameters indicated a significant variation between the two aphid populations, and the variation was influenced by host plants. The performance of melon-aphids was poor (up to 89% reduction in fecundity) on malvaceous hosts, cotton and okra. However, cotton-aphids performed better on cucurbitaceous hosts, squash and watermelon (up to 66% increased fecundity) compared with the natal host, cotton. Both HAPs were able to reproduce on two weed hosts. Cotton-aphids were smaller than melon-aphids irrespective of their host plants. Results from this study suggest that the two HAPs in the study area do not have strict host specialization; rather they exhibit plasticity in utilizing several hosts. In this scenario, it is unlikely that host-associatedA. gossypiipopulations would evolve into host-specific biotypes.
First Impressions: Henry George Ward'sMexico in 1827
Authors: FOWLER WILL 
Published: September 2017

AbstractHenry George Ward'sMexico in 1827(published in 1828) is one of the most exhaustive accounts of Mexico and its mining activities in the years following its independence from Spain. Written with a meticulous attention to detail, it provided a unique first-hand interpretation both of Mexico's early governments’ achievements and of the not insignificant problems they had as yet to overcome. It highlighted the risks and opportunities Mexico presented to potential British investors and emphasised the benefits of free trade, the need for patience, and how important it was to become meaningfully acquainted with the country before investing in one or several ventures there. This study provides for the first time an analysis of Ward's two-volume survey-cum-travelogue. It shows how Ward's cautiously optimistic appraisal faithfully reflected the short-lived hopes of Guadalupe Victoria's 1824–9 government and provides a sympathetic account of the young republic that would prove anything but common in subsequent British representations of Mexico, as the country's inability to service the London debt and its ensuing instability went on to hinder British–Mexican relations for the greater part of the nineteenth century.
New perspectives on language and gender: Linguistic prescription and compliance in call centres
Authors: Hultgren Anna Kristina 
Published: September 2017

AbstractDespite a shift to service-based economies, male-dominated, high-status workplaces have been the predominant focus of research into language and gender in the workplace. This study redresses this shortcoming by considering one female-dominated, low-status, highly regimented workplace that is emblematic of the globalized service economy: call centres. Drawing on 187 call centre service interactions, institutional documents, interviews, and observations from call centres in two national contexts, the study employs an innovative combination of quantitative and qualitative discourse-analytic techniques to compare rule compliance of male and female workers. Female agents in both national contexts are found to comply more with the linguistic prescriptions despite managers and agents emphatically denying the relevance of gender. The study offers a new perspective on language and gender, pointing to the need to expand the methodologies and theories currently favoured to understand how language perpetuates occupational segregation in twenty-first-century workplaces. (Call centres, language and gender, new perspectives, male/female differences, globalized service economy)*
Granular cells in the presence of magnetic field
Authors: Jurčák J. , Lemmerer B. , van Noort M. 
Published: September 2017

AbstractWe present a statistical study of the dependencies of the shapes and sizes of the photospheric convective cells on the magnetic field properties. This analysis is based on a 2.5 hour long SST observations of active region NOAA 11768. We have blue continuum images taken with a cadence of 5.6 sec that are used for segmentation of individual granules and 270 maps of spectropolarimetric CRISP data allowing us to determine the properties of the magnetic field along with the line-of-sight velocities. The sizes and shapes of the granular cells are dependent on the the magnetic field strength, where the granules tend to be smaller in regions with stronger magnetic field. In the presence of highly inclined magnetic fields, the eccentricity of granules is high and we do not observe symmetric granules in these regions. The mean up-flow velocities in granules as well as the granules intensities decrease with increasing magnetic field strength.
A long-duration active region: Evolution and quadrature observations of ejective events
Authors: Cremades H. , Mandrini C. H. , Fuentes M. C. López , Merenda L. , Cabello I. , López F. M. , Poisson M. 
Published: September 2017

AbstractUnknown aspects of the initiation, evolution, and associated phenomena of coronal mass ejections (CMEs), together with their capability of perturbing the fragile technological equilibrium on which nowadays society depends, turn them a compelling subject of study. While space weather forecasts are thus far not able to predict when and where in the Sun will the next CME take place, various CME triggering mechanisms have been proposed, without reaching consensus on which is the predominant one. To improve our knowledge in these respects, we investigate a long-duration active region throughout its life, from birth until decay along five solar rotations, in connection with its production of ejective events. We benefit from the wealth of solar remote-sensing data with improved temporal, spatial, and spectral resolution provided by the ground-breaking space missions STEREO, SDO, and SOHO. During the investigated time interval, which covers the months July – November 2010, the STEREO spacecraft were nearly 180 degrees apart, allowing for the uninterrupted tracking of the active region and its ensuing CMEs. The ejective aspect is examined from multi-viewpoint coronagraphic images, while the dynamics of the active region photospheric magnetic field are inspected by means of SDO/HMI data for specific subintervals of interest. The ultimate goal of this work in progress is to identify common patterns in the ejective aspect that can be connected with the active region characteristics.
A Python-based interface to examine motions in time series of solar images
Authors: Campos-Rozo J. I. , Domínguez S. Vargas 
Published: September 2017

AbstractPython is considered to be a mature programming language, besides of being widely accepted as an engaging option for scientific analysis in multiple areas, as will be presented in this work for the particular case of solar physics research. SunPy is an open-source library based on Python that has been recently developed to furnish software tools to solar data analysis and visualization. In this work we present a graphical user interface (GUI) based on Python and Qt to effectively compute proper motions for the analysis of time series of solar data. This user-friendly computing interface, that is intended to be incorporated to the Sunpy library, uses a local correlation tracking technique and some extra tools that allows the selection of different parameters to calculate, vizualize and analyze vector velocity fields of solar data, i.e. time series of solar filtergrams and magnetograms.
A study on Electron Oscillations in the Magnetosheath of Mars with Mars Express observations
Authors: de Souza Adriane M. , Echer Ezequiel , Bolzam Mauricio J. A. , Fränz Markus 
Published: September 2017

AbstractWavelet analysis was employed to identify the major frequencies of low-frequency waves present in the Martian magnetosheath. The Morlet wavelet transform was selected and applied to the electron density data, obtained from the Analyzer of Space Plasmas and Energetic Atoms experiment (ASPERA-3), onboard the Mars Express (MEX) spacecraft. We have selected magnetosheath crossings and analyzed electron density data. From a preliminary study of 502 magnetosheath crossings (observed during the year of 2005), we have found 1409 periods between 0.005 and 0.06Hz. The major frequencies observed were in the range 0.005-0.02 Hz with 58.5% of the 1409 frequencies identified.
Atmospheric Parameters and Luminosities of Nearby M Dwarfs – Estimating Habitable Exoplanet Detectability with the E-ELT
Authors: Porto de Mello Gustavo F. , Giribaldi Riano E. , Lorenzo-Oliveira Diego , Leme Nathália M. Paes 
Published: September 2017

AbstractWe derive Teff and [Fe/H] for a sample of 72 nearby M-dwarfs with Hipparcos parallaxes and δ < +30. Spectra, acquired at the Observatório do Pico dos Dias, Brazil, have R = 10,000 and S/N ≳ 100 for nearly all targets in the λλ8380-8880 range. Atmospheric parameters were derived from VJHK colors and a system of spectral line indices calibrated against sample stars with interferometric Teff and [Fe/H] from detailed analysis of FGK binary companions. A PCA method of calibration yields internal errors within 70 K and 0.1 dex for Teff and [Fe/H]. For 18 stars we present the first Teff or [Fe/H] derivation in the literature. We compute the star's luminosities, calculate the position of their habitable zones and estimate that, were all of they to harbour rocky planets inside their HZ, 15–20 of these would be detectable by the E-ELT Planetary Camera and Spectrograph.
Deriving the solar activity cycle modulation on cosmic ray intensity observed by Nagoya muon detector from October 1970 until December 2012
Authors: de Mendonça Rafael R. S. , Braga Carlos. R. , Echer Ezequiel , Lago Alisson Dal , Rockenbach Marlos , Schuch Nelson J. , Munakata Kazuoki 
Published: September 2017

AbstractIt is well known that the cosmic ray intensity observed at the Earth's surface presents an 11 and 22-yr variations associated with the solar activity cycle. However, the observation and analysis of this modulation through ground muon detectors datahave been difficult due to the temperature effect. Furthermore, instrumental changes or temporary problems may difficult the analysis of these variations. In this work, we analyze the cosmic ray intensity observed since October 1970 until December 2012 by the Nagoya muon detector. We show the results obtained after analyzing all discontinuities and gaps present in this data and removing changes not related to natural phenomena. We also show the results found using the mass weighted method for eliminate the influence of atmospheric temperature changes on muon intensity observed at ground. As a preliminary result of our analyses, we show the solar cycle modulation in the muon intensity observed for more than 40 years.
Exploring shallow sunspot formation by using Implicit Large-eddy simulations
Authors: Camacho F. J. , Guerrero G. , Smolarkiewicz P. K. , Kosovichev A. G. , Mansour N. N. 
Published: September 2017

AbstractThe mechanism by which sunspots are generated at the surface of the sun remains unclear. In the current literature two types of explanations can be found. The first one is related to the buoyant emergence of toroidal magnetic fields generated at the tachocline. The second one states that active regions are formed, from initially diffused magnetic flux, by MHD instabilities that develop in the near-surface layers of the Sun. Using the anelastic MHD code EULAG we address the problem of sunspot formation by performing implicit large-eddy simulations of stratified magneto-convection in a domain that resembles the near-surface layers of the Sun. The development of magnetic structures is explored as well as their effect on the convection dynamics. By applying a homogeneous magnetic field over an initially stationary hydrodynamic convective state, we investigate the formation of self-organized magnetic structures in the range of the initial magnetic field strength, 0.01 < B0/Beq < 0.5, where Beq is the characteristic equipartition field strength.
Hunting for Stellar Coronal Mass Ejections
Authors: Korhonen Heidi , Vida Krisztián , Leitzinger Martin , Odert Petra , Kovács Orsolya Eszter 
Published: September 2017

AbstractCoronal mass ejections (CMEs) are explosive events that occur basically daily on the Sun. It is thought that these events play a crucial role in the angular momentum and mass loss of late-type stars, and also shape the environment in which planets form and live. Stellar CMEs can be detected in optical spectra in the Balmer lines, especially in Hα, as blue-shifted extra emission/absorption. To increase the detection probability one can monitor young open clusters, in which the stars are due to their youth still rapid rotators, and thus magnetically active and likely to exhibit a large number of CMEs. Using ESO facilities and the Nordic Optical Telescope we have obtained time series of multi-object spectroscopic observations of late-type stars in six open clusters with ages ranging from 15 Myrs to 300 Myrs. Additionally, we have studied archival data of numerous active stars. These observations will allow us to obtain information on the occurrence rate of CMEs in late-type stars with different ages and spectral types. Here we report on the preliminary outcome of our studies.
Magnetic field generation in PMS stars with and without radiative core
Authors: Zaire B. , Guerrero G. , Kosovichev A. G. , Smolarkiewicz P. K. , Landin N. R. 
Published: September 2017

AbstractRecent observations of the magnetic field in pre-main sequence stars suggest that the magnetic field topology changes as a function of age. The presence of a tachocline could be an important factor in the development of magnetic field with higher multipolar modes. In this work we performed MHD simulations using the EULAG-MHD code to study the magnetic field generation and evolution in models that mimic stars at two evolutionary stages. The stratification for both stellar phases was computed by fitting stellar structure profiles obtained with the ATON stellar evolution code. The first stage is at 1.1Myr, when the star is completely convective. The second stage is at 14Myrs, when the star is partly convective, with a radiative core developed up to 30% of the stellar radius. In this proceedings we present a preliminary analysis of the resulting mean-flows and magnetic field. The mean-flow analysis shown that the star rotate almost rigidly on the fully convective phase, whereas at the partially convective phase there is differential rotation with conical contours of iso-rotation. As for the mean magnetic field both simulations show similarities with respect to the field evolution. However, the topology of the magnetic field is different.
Initiation and chromospheric effects of a M1.0 class solar flare from high-resolution multi-wavelength observations
Authors: Sadykov V. M. , Kosovichev A. G. , Sharykin I. N. , Zimovets I. V. , Dominguez S. Vargas 
Published: September 2017

AbstractInitiation and development of a M 1.0 class flare of June 12, 2014, was observed by space and ground-based telescopes, including EUV and X-ray imaging spectroscopy by IRIS and RHESSI, and high-resolution optical imaging by 1.6 m New Solar Telescope (NST). Analyzing the NST data, we found small-scale loop-like structures in the region of the magnetic field Polarity Inversion Line (PIL), the emergence and interaction of which caused photospheric brightenings temporarily coinciding with hard X-ray impulses. Detailed studies of the PIL region reveal signatures of photospheric plasma downflows and dissipation of electric currents. The reconstructed magnetic field topology shows a bundle of lines connecting the PIL region with the flare ribbons which were places of chromospheric evaporation observed by IRIS. The observations suggest a scenario with the primary energy release processes located in the low atmospheric layers of the PIL, energizing the overlying large-scale magnetic structure and causing “gentle” chromospheric evaporation.
P-mode induced convective collapse in vertical expanding magnetic flux tubes?
Authors: Utz D. , Van Doorsselaere T. , Magyar N. , Bárta M. , Campos Rozo J. I. 
Published: September 2017

AbstractSmall-scale kG strong magnetic field elements in the solar photosphere are often identified as so-called magnetic bright points (MBPs). In principle these MBPs represent the cross-section of a vertical, strong, magnetic flux tube which is expanding with height in the solar atmosphere. As these magnetic elements represent possible MHD wave guides, a significant interest has been already paid to them from the viewpoint of observations and simulations. In this work we would like to shed more light on a possible scenario for the creation of such strong magnetic field concentrations. The accepted standard scenario involves the convective collapse process. In this ongoing work we will show indications that this convective collapse process may become triggered by sufficiently strong pressure disturbances. However, it is highly unlikely that p-mode waves can be of such a strength.
Common variants in MMP20 at 11q22.2 predispose to 11q deletion and neuroblastoma risk
Authors: Chang Xiao , Zhao Yan , Hou Cuiping , Glessner Joseph , McDaniel Lee , Diamond Maura A. , Thomas Kelly , Li Jin , Wei Zhi , Liu Yichuan , Guo Yiran , Mentch Frank D. , Qiu Haijun , Kim Cecilia , Evans Perry , Vaksman Zalman , Diskin Sharon J. , Attiyeh Edward F. , Sleiman Patrick , Maris John M. , Hakonarson Hakon 
Published: September 2017

AbstractMYCN amplification and 11q deletion are two inversely correlated prognostic factors of poor outcome in neuroblastoma. Here we identify common variants at 11q22.2 within MMP20 that associate with neuroblastoma cases harboring 11q deletion (rs10895322), using GWAS in 113 European-American cases and 5109 ancestry-matched controls. The association is replicated in 44 independent cases and 1902 controls. Our study yields novel insights into the genetic underpinnings of neuroblastoma, demonstrating that the inherited common variants reported contribute to the origin of intra-tumor genetic heterogeneity in neuroblastoma.
SRpHi ratiometric pH biosensors for super-resolution microscopy
Authors: Richardson Douglas S. , Gregor Carola , Winter Franziska R. , Urban Nicolai T. , Sahl Steffen J. , Willig Katrin I. , Hell Stefan W. 
Published: September 2017

AbstractFluorescence-based biosensors have become essential tools for modern biology, allowing real-time monitoring of biological processes within living cells. Intracellular fluorescent pH probes comprise one of the most widely used families of biosensors in microscopy. One key application of pH probes has been to monitor the acidification of vesicles during endocytosis, an essential function that aids in cargo sorting and degradation. Prior to the development of super-resolution fluorescence microscopy (nanoscopy), investigation of endosomal dynamics in live cells remained difficult as these structures lie at or below the ~250 nm diffraction limit of light microscopy. Therefore, to aid in investigations of pH dynamics during endocytosis at the nanoscale, we have specifically designed a family of ratiometric endosomal pH probes for use in live-cell STED nanoscopy.
Novel ecto-tagged integrins reveal their trafficking in live cells
Authors: Huet-Calderwood Clotilde , Rivera-Molina Felix , Iwamoto Daniel V. , Kromann Emil B. , Toomre Derek , Calderwood David A. 
Published: September 2017

AbstractIntegrins are abundant heterodimeric cell-surface adhesion receptors essential in multicellular organisms. Integrin function is dynamically modulated by endo-exocytic trafficking, however, major mysteries remain about where, when, and how this occurs in living cells. To address this, here we report the generation of functional recombinant β1 integrins with traceable tags inserted in an extracellular loop. We demonstrate that these ‘ecto-tagged’ integrins are cell-surface expressed, localize to adhesions, exhibit normal integrin activation, and restore adhesion in β1 integrin knockout fibroblasts. Importantly, β1 integrins containing an extracellular pH-sensitive pHluorin tag allow direct visualization of integrin exocytosis in live cells and revealed targeted delivery of integrin vesicles to focal adhesions. Further, using β1 integrins containing a HaloTag in combination with membrane-permeant and -impermeant Halo dyes allows imaging of integrin endocytosis and recycling. Thus, ecto-tagged integrins provide novel powerful tools to characterize integrin function and trafficking.
Rational development of catalytic Au(I)/Au(III) arylation involving mild oxidative addition of aryl halides
Authors: Zeineddine Abdallah , Estévez Laura , Mallet-Ladeira Sonia , Miqueu Karinne , Amgoune Abderrahmane , Bourissou Didier 
Published: September 2017

AbstractThe reluctance of gold to achieve oxidative addition reaction is considered as an intrinsic limitation for the development of gold-catalyzed cross-coupling reactions with simple and ubiquitous aryl halide electrophiles. Here, we report the rational construction of a Au(I)/Au(III) catalytic cycle involving a sequence of Csp2–X oxidative addition, Csp2–H auration and reductive elimination, allowing a gold-catalyzed direct arylation of arenes with aryl halides. Key to this discovery is the use of Me-Dalphos, a simple ancillary (P,N) ligand, that allows the bottleneck oxidative addition of aryl iodides and bromides to readily proceed under mild conditions. The hemilabile character of the amino group plays a crucial role in this transformation, as substantiated by density functional theory calculations.