bluuebunny/crossref_metadata_2025_split huggingface dataset:
Emergence of Magnetic Flux Generated in a Solar Convective Dynamo. I. The Formation of Sunspots and Active Regions, and The Origin of Their Asymmetries
Authors: Chen Feng , Rempel Matthias , Fan Yuhong 
Published: September 2017

Abstract
We present a realistic numerical model of sunspot and active region formation based on the emergence of flux bundles generated in a solar convective dynamo. To this end, we use the magnetic and velocity fields in a horizontal layer near the top boundary of the solar convective dynamo simulation to drive realistic radiative-magnetohydrodynamic simulations of the uppermost layers of the convection zone. The main results are as follows. (1) The emerging flux bundles rise with the mean speed of convective upflows and fragment into small-scale magnetic elements that further rise to the photosphere, where bipolar sunspot pairs are formed through the coalescence of the small-scale magnetic elements. (2) Filamentary penumbral structures form when the sunspot is still growing through ongoing flux emergence. In contrast to the classical Evershed effect, the inflow seems to prevail over the outflow in a large part of the penumbra. (3) A well-formed sunspot is a mostly monolithic magnetic structure that is anchored in a persistent deep-seated downdraft lane. The flow field outside the spot shows a giant vortex ring that comprises an inflow below 15 Mm depth and an outflow above 15 Mm depth. (4) The sunspots successfully reproduce the fundamental properties of the observed solar active regions, including the more coherent leading spots with a stronger field strength, and the correct tilts of bipolar sunspot pairs. These asymmetries can be linked to the intrinsic asymmetries in the magnetic and flow fields adapted from the convective dynamo simulation.
« Nous avons la responsabilité de nous engager ! »
Authors: Brac de La Perrière Louis 
Published: September 2017

Louis Brac de La Perrière est étudiant en 4 ème année à la Faculté de Lyon Est et membre du Centre Laennec Lyon. En 2012, avec un petit groupe d’amis, il a lancé une association humanitaire « Terre Solidaire », qui fédère jusqu’à ce jour des projets dans son lycée d’origine, Notre-Dame de Bellegarde, comme au Centre Laennec Lyon. Tous les ans, des étudiants du Centre et d’ailleurs partent au Togo avec cette association pour mener des projets humanitaires. Dans cette interview, il partage son aventure et élargit son regard à l’engagement humanitaire et sur les liens qu’il fait avec sa vie d’externe. Propos recueillis et mis en forme par Gonzague Lalanne-Berdouticq, sj, formateur au Centre Laennec Lyon.
Loss of Circulating Mucosal-Associated Invariant T Cells in Common Variable Immunodeficiency Is Associated with Immune Activation and Loss of Eomes and PLZF
Authors: Paquin-Proulx Dominic , Santos Bianca A N , Barsotti Nathália Silveira , Marinho Ana Karolina B B , Kokron Cristina M , Carvalho Karina I , Barros Myrthes T , Kalil Jorge , Elmacken Mona , Sandberg Johan K , Kallas Esper G , Nixon Douglas F 
Published: September 2017

Abstract
Common variable immunodeficiency (CVID) is characterized by low levels of Igs leading to increased risk of infections. Mucosal-associated invariant T (MAIT) cells are a recently identified population of innate T cells with potent antibacterial activity. We hypothesized that CVID is associated with alterations in MAIT cells. Cryopreserved PBMC from CVID patients and healthy controls were used to study the frequency, phenotype, and response to Escherichia coli stimulation of MAIT cells by flow cytometry. MAIT cell frequency and absolute counts were depressed in CVID. Residual MAIT presented elevated coexpression of CD38 and HLA-DR, and reduced expression of CCR6, whereas levels of CD127 (IL-7 receptor) were unchanged. CVID patients also had an accumulation of MAIT cells lacking the critical transcription factors eomesodermin and promyelocytic leukemia zinc finger protein. MAIT cell frequency was inversely associated with levels of soluble CD14, with coexpression of CD38 and HLA-DR, and accumulation of MAIT cells lacking eomesodermin or promyelocytic leukemia zinc finger protein expression. None of these changes were normalized by IgG replacement therapy. Finally, MAIT cells from CVID patients displayed poor IFN-γ responses to E. coli stimulation, in part due to defective Ag presentation, and these responses were increased by pretreatment with IL-7. Defective MAIT cell response may contribute to the increased incidence of microbial infections seen in CVID patients on IgG replacement therapy.
IL-4/IL-13 Signaling Inhibits the Potential of Early Thymic Progenitors To Commit to the T Cell Lineage
Authors: Barik Subhasis , Miller Mindy M. , Cattin-Roy Alexis N. , Ukah Tobechukwu K. , Chen Weirong , Zaghouani Habib 
Published: September 2017

Abstract
Early thymic progenitors (ETPs) are endowed with diverse potencies and can give rise to myeloid and lymphoid lineage progenitors. How the thymic environment guides ETP commitment and maturation toward a specific lineage remains obscure. We have previously shown that ETPs expressing the heteroreceptor (HR) comprising IL-4Rα and IL-13Rα1 give rise to myeloid cells but not T cells. In this article, we show that signaling through the HR inhibits ETP maturation to the T cell lineage but enacts commitment toward the myeloid cells. Indeed, HR+ ETPs, but not HR− ETPs, exhibit activated STAT6 transcription factor, which parallels with downregulation of Notch1, a critical factor for T cell development. Meanwhile, the myeloid-specific transcription factor C/EBPα, usually under the control of Notch1, is upregulated. Furthermore, in vivo inhibition of STAT6 phosphorylation restores Notch1 expression in HR+ ETPs, which regain T lineage potential. In addition, upon stimulation with IL-4 or IL-13, HR− ETPs expressing virally transduced HR also exhibit STAT6 phosphorylation and downregulation of Notch1, leading to inhibition of lymphoid, but not myeloid, lineage potential. These observations indicate that environmental cytokines play a role in conditioning ETP lineage choice, which would impact T cell development.
Evaluation Algorithm of PHT-Spline Surfaces
Authors: Wang Zhihua , Chen Falai , Deng Jiansong 
Published: September 2017

AbstractPHT-splines are a type of polynomial splines over hierarchical T-meshes which posses perfect local refinement property. This property makes PHT-splines useful in geometric modeling and iso-geometric analysis. Current implementation of PHT-splines stores the basis functions in Bézier forms, which saves some computational costs but consumes a lot of memories. In this paper, we propose a de Boor like algorithm to evaluate PHT-splines provided that only the information about the control coefficients and the hierarchical mesh structure is given. The basic idea is to represent a PHT-spline locally in a tensor product B-spline, and then apply the de-Boor algorithm to evaluate the PHT-spline at a certain parameter pair. We perform analysis about computational complexity and memory costs. The results show that our algorithm takes about the same order of computational costs while requires much less amount of memory compared with the Bézier representations. We give an example to illustrate the effectiveness of our algorithm.
Anisotropic Mesh Adaptation for 3D Anisotropic Diffusion Problems with Application to Fractured Reservoir Simulation
Authors: Li Xianping , Huang Weizhang 
Published: September 2017

AbstractAnisotropic mesh adaptation is studied for linear finite element solution of 3D anisotropic diffusion problems. The 𝕄-uniform mesh approach is used, where an anisotropic adaptive mesh is generated as a uniform one in the metric specified by a tensor. In addition to mesh adaptation, preservation of the maximum principle is also studied. Some new sufficient conditions for maximum principle preservation are developed, and a mesh quality measure is defined to server as a good indicator. Four different metric tensors are investigated: one is the identity matrix, one focuses on minimizing an error bound, another one on preservation of the maximum principle, while the fourth combines both. Numerical examples show that these metric tensors serve their purposes. Particularly, the fourth leads to meshes that improve the satisfaction of the maximum principle by the finite element solution while concentrating elements in regions where the error is large. Application of the anisotropic mesh adaptation to fractured reservoir simulation in petroleum engineering is also investigated, where unphysical solutions can occur and mesh adaptation can help improving the satisfaction of the maximum principle.
In My Nicaraguan High School: Giving Excluded Women and Men a Second Chance
Authors: Gullette Margaret Morganroth 
Published: September 2017

When I went to Nicaragua for the first time during the Contra war, I had no idea that I would soon wind up helping a Nica friend start two literacy programs and then a Free High School for Adults. It opened in 2002, and now, only 15 years later, we have 1001 graduates, 54% women, 45% rural (mainly from subsistence farm families)--all of them excluded from the regular high schools for one reason or another: being pregnant, being a woman, turning eighteen, working five days a week, or living too far from town without the ability to pay bus fare. My real education came with theirs and is still going on, with no end in sight. What I wanted to know was how the teachers--all college graduates who were teaching in the high prestige regular high schools--figured out how to teach these people, many of whom had been out of school for decades and were unused to learning or scholastic discipline; many accustomed to being heads of households; some pregnant or carrying a baby to School for lack of child care or need to nurse; some drunk or exhausted early on Saturday mornings when classes began. The teachers told me their own stories, of overcoming prejudice and learning how to create a welcoming atmosphere. And the graduates told me THEIR stories, of what it took to succeed in those conditions, and how education--especially learning how to speak better-- transformed them, and they, in turn, transformed the entire culture and economy of the region.
DO WE NEED VERY STIFF FILLERS?
Authors: Jiang Bing 
Published: September 2017

ABSTRACT
The influence of reinforcing fillers on the stretching of a rubber matrix is analyzed. It is shown that a filler stiffness higher than a critical stiffness does not further enhance the stiffness of the reinforced elastomer. The stiffer filler induces a higher stress–strain concentration and causes filler–rubber dissociation or chain scission at a lower macroscopic strain. Reducing filler stiffness can reduce the stress–strain concentration and therefore delay rubber chain scission or dissociation from the filler surface. Accordingly, the toughness of the reinforced elastomer could be improved. A simple material model is developed to predict the maximum macroscopic strain without bond scission in a reinforced elastomer. It is shown that reduced filler stiffness is beneficial for cases with (i) reduced bond strength, (ii) increased rubber matrix stiffness, and (iii) increased application strain of the reinforced elastomer. The model can be used to design the appropriate filler stiffness to balance trade-offs of stiffness and toughness of reinforced elastomers.
Evaluation of Safety in Exceeding Maximum Adult Doses of Commonly Used Second-Generation Antiepileptic Drugs in Pediatric Patients
Authors: Messinger Mindl M. , Misra Sunita N. , Clark Gary D. , DiCarlo Shannon M. 
Published: September 2017

OBJECTIVEPediatric patients often require larger doses of antiepileptic drug (AED) than adults in order to attain therapeutic serum concentrations and/or achieve seizure control. Safety and efficacy data are often extrapolated from adult literature; hence, optimal dosage may only be determined anecdotally or based on expert opinion. With limited pediatric dosing guidelines, milligrams per day that are based on weight may exceed the maximum adult dose. The primary objective of this study is to evaluate the safety of exceeding maximum doses as specified by the US Food and Drug Administration or manufacturers of commonly used AEDs in pediatric patients.METHODSThis study is a single-center, retrospective analysis of all pediatric patients seen in the outpatient clinic between October 2010 and October 2014 who were prescribed a dose that exceeds the maximum approved dose of oxcarbazepine, zonisamide, topiramate, levetiracetam, lamotrigine, or clobazam. Baseline demographics (ie, sex, age, race/ethnicity, weight, height, diagnosis), serum drug concentrations, and appropriate laboratory tests were collected. Side effects were reviewed.RESULTSDuring the 4-year study period, 41,137 prescriptions were included. A total of 2% of prescriptions exceeded the maximum dose of 1 of the included AEDs. The most common AED prescribed above the maximum dose was levetiracetam (53%), whereas lamotrigine was the least common (6%). The largest doses prescribed exceeded the maximum by 3-fold (i.e., levetiracetam dose of 9000 mg/day).CONCLUSIONIt appears safe to use doses exceeding the maximum approved dose of the evaluated AEDs in pediatric patients, with appropriate counseling and monitoring for adverse effects.
The Effect of Authentic Problem-Based Vocabulary Tasks on Vocabulary Learning of EFL Learners
Authors: Mohammadi Fateme Shir 
Published: September 2017

Language learners’ cognitive engagement with the content in language classes has been advocated in the last few decades (Laufer & Hulstjin, 2001). To this end, the researcher designed authentic problem-based tasks which make use of learners’ cognitive and metacognitive skills to solve real-life vocabulary tasks. Nelson vocabulary test was administered to 64 Iranian EFL learners studying at a language institute in Tehran. By considering 1 standard deviation above and below the mean score, two cohorts of participants were selected for this study, i.e., the experimental group (n=24) and the control group (n=23). Conventional vocabulary learning tasks were implemented in the control group classes for 10 sessions while authentic problem-based vocabulary learning tasks were implemented in experimental group classes. The results of data analysis revealed that the experimental group participants outperformed the control group learners in both tests of vocabulary recall and vocabulary retention (administered after a two-week interval). Pedagogical Implications are discussed.
Latitude Dependence of Low‐Altitude O+ Ion Upflow: Statistical Results From FAST Observations
Authors: Zhao K. , Chen K. W. , Jiang Y. , Chen W. J. , Huang L. F. , Fu S. 
Published: September 2017

AbstractWe introduce a statistical model to explain the latitudinal dependence of the occurrence rate and energy flux of the ionospheric escaping ions, taking advantage of advances in the spatial coverage and accuracy of FAST observations. We use a weighted piecewise Gaussian function to fit the dependence, because two probability peaks are located in the dayside polar cusp source region and the nightside auroral oval zone source region. The statistical results show that (1) the Gaussian Mixture Model suitably describes the dayside polar cusp upflows, and the dayside and the nightside auroral oval zone upflows. (2) The magnetic latitudes of the ionospheric upflow source regions expand toward the magnetic equator as Kp increases, from 81° magnetic latitude (MLAT) (cusp upflows) and 63° MLAT (auroral oval upflows) during quiet times to 76° MLAT and 61° MLAT, respectively. (3) The dayside polar cusp region provides only 3–5% O+ upflows among all the source regions, which include the dayside auroral oval zone, dayside polar cusp, nightside auroral oval zone, and even the polar cap. However, observations show that more than 70% of upflows occur in the auroral oval zone and that the occurrence probability increases at the altitudes of 3500–4200 km, which is considered to be the lower altitude boundary of ion beams. This observed result suggests that soft electron precipitation and transverse wave heating are the most efficient ion energization/acceleration mechanisms at the altitudes of FAST orbit, and that the parallel acceleration caused by field‐aligned potential drops becomes effective above that altitude.
A Simulation Study of the Equatorial Ionospheric Response to the October 2013 Geomagnetic Storm
Authors: Ren Dexin , Lei Jiuhou 
Published: September 2017

AbstractThe ionospheric observation from ionosonde at Sao Luis (2.5°S, 44.2°W; 6.68°S dip latitude) around the magnetic equator showed that the nighttime ionospheric F2 layer was uplifted by more than 150 km during the October 2013 geomagnetic storm. The changes of the F2 peak height (hmF2) at the magnetic equator were generally attributed to the variations of vertical drift associated with zonal electric fields. In this paper, the Thermosphere Ionosphere Electrodynamics General Circulation Model (TIEGCM) simulation results are utilized to explore the possible physical mechanisms responsible for the observed increase of hmF2 at Sao Luis. The TIEGCM generally reproduced the changes of F2 peak electron density (NmF2) and its height (hmF2) during the main and recovery phases of the October 2013 storm. A series of controlled simulations revealed that storm time hmF2 changes at the magnetic equator are not purely associated with the changes of electric fields; horizontal plasma transport due to meridional winds and thermospheric expansion also contributed significantly to the profound increase of nighttime hmF2 observed at Sao Luis on 2 October. Moreover, the changes of meridional winds and neutral temperature in the equatorial region are associated with storm time traveling atmospheric disturbances originating from high latitudes.
Impact of Sudden Stratospheric Warming of 2009 on the Equatorial and Low‐Latitude Ionosphere of the Indian Longitudes: A Case Study
Authors: Yadav Sneha , Pant Tarun K. , Choudhary R. K. , Vineeth C. , Sunda Surendra , Kumar K. K. , Shreedevi P. R. , Mukherjee S. 
Published: September 2017

AbstractUsing the equatorial electrojet (EEJ)‐induced surface magnetic field and total electron content (TEC) measurements, we investigated the impact of the sudden stratospheric warming (SSW) of January 2009 on the equatorial electrodynamics and low‐latitude ionosphere over the Indian longitudes. Results indicate that the intensity of EEJ and the TEC over low latitudes (extending up to 30°N) exhibit significant perturbations during and after the SSW peak. One of the interesting features is the deviation of EEJ and TEC from the normal quiet time behavior well before the onset of the SSW. This is found to coincide with the beginning of enhanced planetary wave (PW) activity over high latitudes. The substantial amplification of the semidiurnal perturbation after the SSW peak is seen to be coinciding with the onset of new and full moons. The response of TEC to SSW is found to be latitude dependent as the near‐equatorial (NE) stations show the semidiurnal perturbation only after the SSW peak. Another notable feature is the presence of reduced ionization in the night sector over the NE and low‐latitude regions, appearing as an “ionization hole,” well after the SSW peak. The investigation revealed the existence of a quasi 16 day wave in the TEC over low latitudes similar to the one present in the EEJ strength. These results have been discussed in the light of changes in the dynamical background because of enhanced PW activity during SSW, which creates favorable conditions for the amplification of lunar tides, and their subsequent interaction with the lower thermospheric tidal fields.
Polar Thermospheric Winds and Temperature Observed by Fabry‐Perot Interferometer at Jang Bogo Station, Antarctica
Authors: Lee Changsup , Jee Geonhwa , Wu Qian , Shim Ja Soon , Murphy Damian , Song In‐Sun , Kwon Hyuck‐Jin , Kim Jeong‐Han , Kim Yong Ha 
Published: September 2017

AbstractUpper atmospheric neutral winds and temperature have been observed by the Fabry‐Perot interferometer (FPI) which was installed at Jang Bogo Station (JBS), Antarctica, in 2014. Since JBS is mostly located within the polar cap region, the observed thermospheric winds at 250 km show strong diurnal variations with notable antisunward motions due to the effects of plasma convection. The winds at 87 km, on the other hand, show semidiurnal variations due to the lower atmospheric tidal effects. We found that the winds from green line emission show largely diurnal variations, unlike the other independent observations, which might be due to the auroral contamination. The horizontal wind model 2014 winds at 250 km show reasonable agreement with FPI winds, while large discrepancies exist at 87 km in terms of seasonal variations. There is a distinctive asymmetric seasonal variation of the thermospheric zonal wind in the dusk and dawn sectors. FPI temperatures at 250 km show a fairly close correlation with Kp index, especially in 2015 when the geomagnetic activity is stronger. However, the temperatures at 87 km are mostly independent on Kp index. Finally, during the intense geomagnetic storm, thermospheric winds and temperature are significantly disturbed and Thermosphere Ionosphere Electrodynamics General Circulation Model simulations are in surprisingly good agreement with observation for winds but the temperatures are significantly underestimated during the whole storm period.
The Martian Photoelectron Boundary as Seen by MAVEN
Authors: Garnier P. , Steckiewicz M. , Mazelle C. , Xu S. , Mitchell D. , Holmberg M. K. G. , Halekas J. S. , Andersson L. , Brain D. A. , Connerney J. E. P. , Espley J. R. , Lillis R. J. , Luhmann J. G. , Sauvaud J.‐A. , Jakosky B. M. 
Published: September 2017

AbstractPhotoelectron peaks in the 20–30 eV energy range are commonly observed in the planetary atmospheres, produced by the intense photoionization from solar 30.4 nm photons. At Mars, these photoelectrons are known to escape the planet down its tail, making them tracers for the atmospheric escape. Furthermore, their presence or absence allow to define the so‐called photoelectron boundary (PEB), which separates the photoelectron dominated ionosphere from the external environment. We provide here a detailed statistical analysis of the location and properties of the PEB based on the Mars Atmosphere and Volatile EvolutioN (MAVEN) electron and magnetic field data obtained from September 2014 to May 2016 (including 1696 PEB crossings). The PEB appears as mostly sensitive to the solar wind dynamic and crustal fields pressures. Its variable altitude thus leads to a variable wake cross section for escape (up to ∼+50%), which is important for deriving escape rates. The PEB is not always sharp and is characterized on average by the following: a magnetic field topology typical for the end of magnetic pileup region above it, more field‐aligned fluxes above than below, and a clear change of the altitude slopes of both electron fluxes and total density (that appears different from the ionopause). The PEB thus appears as a transition region between two plasma and fields configurations determined by the draping topology of the interplanetary magnetic field around Mars and much influenced by the crustal field sources below, whose dynamics also impacts the estimated escape rate of ionospheric plasma.