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Dust Polarization toward Embedded Protostars in Ophiuchus with ALMA. I. VLA 1623
Sadavoy, Sarah I.,Myers, Philip C.,Stephens, Ian W.,Tobin, John,Commerç,on, Benoî,t,Henning, Thomas,Looney, Leslie,Kwon, Woojin,Segura-Cox, Dominique,Harris, Robert American Astronomical Society 2018 The Astrophysical journal Vol.859 No.2
<P>We present high-resolution (similar to 30 au) ALMA Band 6 dust polarization observations of VLA 1623. The VLA 1623 data resolve compact similar to 40 au inner disks around the two protobinary sources, VLA 1623-A and VLA 1623-B, and also an extended similar to 180 au ring of dust around VLA 1623-A. This dust ring was previously identified as a large disk in lower-resolution observations. We detect highly structured dust polarization toward the inner disks and the extended ring with typical polarization fractions similar to 1.7% and similar to 2.4%, respectively. The two components also show distinct polarization morphologies. The inner disks have uniform polarization angles aligned with their minor axes. This morphology is consistent with expectations from dust scattering. By contrast, the extended dust ring has an azimuthal polarization morphology not previously seen in lower-resolution observations. We find that our observations are well-fit by a static, oblate spheroid model with a flux-frozen, poloidal magnetic field. We propose that the polarization traces magnetic grain alignment likely from flux freezing on large scales and magnetic diffusion on small scales. Alternatively, the azimuthal polarization may be attributed to grain alignment by the anisotropic radiation field. If the grains are radiatively aligned, then our observations indicate that large (similar to 100 mu m) dust grains grow quickly at large angular extents. Finally, we identify significant proper motion of VLA 1623 using our observations and those in the literature. This result indicates that the proper motion of nearby systems must be corrected for when combining ALMA data from different epochs.</P>
Evans, D. F.,Southworth, J.,Smalley, B.,Jørgensen, U. G.,Dominik, M.,Andersen, M. I.,Bozza, V.,Bramich, D. M.,Burgdorf, M. J.,Ciceri, S.,D’Ago, G.,Figuera Jaimes, R.,Gu, S.-H.,Hinse, T. C.,Henning, Th Springer-Verlag 2018 Astronomy and astrophysics Vol.610 No.-
<P><I>Context.</I> The formation and dynamical history of hot Jupiters is currently debated, with wide stellar binaries having been suggested as a potential formation pathway. Additionally, contaminating light from both binary companions and unassociated stars can significantly bias the results of planet characterisation studies, but can be corrected for if the properties of the contaminating star are known.</P><P><I>Aim.</I> We search for binary companions to known transiting exoplanet host stars, in order to determine the multiplicity properties of hot Jupiter host stars. We also search for and characterise unassociated stars along the line of sight, allowing photometric and spectroscopic observations of the planetary system to be corrected for contaminating light.</P><P><I>Methods.</I> We analyse lucky imaging observations of 97 Southern hemisphere exoplanet host stars, using the Two Colour Instrument on the Danish 1.54 m telescope. For each detected companion star, we determine flux ratios relative to the planet host star in two passbands, and measure the relative position of the companion. The probability of each companion being physically associated was determined using our two-colour photometry.</P><P><I>Results.</I> A catalogue of close companion stars is presented, including flux ratios, position measurements, and estimated companion star temperature. For companions that are potential binary companions, we review archival and catalogue data for further evidence. For WASP-77AB and WASP-85AB, we combine our data with historical measurements to determine the binary orbits, showing them to be moderately eccentric and inclined to the line of sight (and hence planetary orbital axis). Combining our survey with the similar Friends of Hot Jupiters survey, we conclude that known hot Jupiter host stars show a deficit of high mass stellar companions compared to the field star population; however, this may be a result of the biases in detection and target selection by ground-based surveys.</P>
Prospects of Nanoscience with Nanocrystals
Kovalenko, Maksym V.,Manna, Liberato,Cabot, Andreu,Hens, Zeger,Talapin, Dmitri V.,Kagan, Cherie R.,Klimov, Victor I.,Rogach, Andrey L.,Reiss, Peter,Milliron, Delia J.,Guyot-Sionnnest, Philippe,Konstan American Chemical Society 2015 ACS NANO Vol.9 No.2
<P>Colloidal nanocrystals (NCs, <I>i.e.</I>, crystalline nanoparticles) have become an important class of materials with great potential for applications ranging from medicine to electronic and optoelectronic devices. Today’s strong research focus on NCs has been prompted by the tremendous progress in their synthesis. Impressively narrow size distributions of just a few percent, rational shape-engineering, compositional modulation, electronic doping, and tailored surface chemistries are now feasible for a broad range of inorganic compounds. The performance of inorganic NC-based photovoltaic and light-emitting devices has become competitive to other state-of-the-art materials. Semiconductor NCs hold unique promise for near- and mid-infrared technologies, where very few semiconductor materials are available. On a purely fundamental side, new insights into NC growth, chemical transformations, and self-organization can be gained from rapidly progressing <I>in situ</I> characterization and direct imaging techniques. New phenomena are constantly being discovered in the photophysics of NCs and in the electronic properties of NC solids. In this Nano Focus, we review the state of the art in research on colloidal NCs focusing on the most recent works published in the last 2 years.</P><P><B>Graphic Abstract</B> <IMG SRC='http://pubs.acs.org/appl/literatum/publisher/achs/journals/content/ancac3/2015/ancac3.2015.9.issue-2/nn506223h/production/images/medium/nn-2014-06223h_0020.gif'></P>
Kosmas I. Paraskevas,Dimitri P. Mikhailidis,Hediyeh Baradaran,Alun H. Davies,Hans-Henning Eckstein,Gianluca Faggioli,Jose Fernandes e Fernandes,Ajay Gupta,Mateja K. Jezovnik,Stavros K. Kakkos,Niki Kat 대한뇌졸중학회 2021 Journal of stroke Vol.23 No.2
The optimal management of patients with asymptomatic carotid stenosis (ACS) is the subject of extensive debate. According to the 2017 European Society for Vascular Surgery guidelines, carotid endarterectomy should (Class IIa; Level of Evidence: B) or carotid artery stenting may be considered (Class IIb; Level of Evidence: B) in the presence of one or more clinical/imaging characteristics that may be associated with an increased risk of late ipsilateral stroke (e.g., silent embolic infarcts on brain computed tomography/magnetic resonance imaging, progression in the severity of ACS, a history of contralateral transient ischemic attack/stroke, microemboli detection on transcranial Doppler, etc.), provided documented perioperative stroke/death rates are <3% and the patient’s life expectancy is >5 years. Besides these clinical/imaging characteristics, there are additional individual, ethnic/racial or social factors that should probably be evaluated in the decision process regarding the optimal management of these patients, such as individual patient needs/patient choice, patient compliance with best medical treatment, patient sex, culture, race/ethnicity, age and comorbidities, as well as improvements in imaging/operative techniques/outcomes. The present multispecialty position paper will present the rationale why the management of patients with ACS may need to be individualized.
Dust Polarization toward Embedded Protostars in Ophiuchus with ALMA. II. IRAS 16293-2422
Sadavoy, Sarah I.,Myers, Philip C.,Stephens, Ian W.,Tobin, John,Kwon, Woojin,Segura-Cox, Dominique,Henning, Thomas,Commerç,on, Benoî,t,Looney, Leslie American Astronomical Society 2018 The Astrophysical journal Vol.869 No.2
Shinyoung Lim,Lawrence Chung,Sumi Helal,Hen-I Yang 한국지능시스템학회 2009 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.9 No.3
In this paper, design of framework architecture of pervasive computing system providing seamless inter space interactions between private and public smart spaces is presented. The seamless inter space interaction issues are related to establishing user's service environment by allocating relevant resources in a new location where there are no prior settings for the user or where there are current users already being served in the new location. In the realm of pervasive computing, we can have different types of smart spaces, offering proactive and intelligent services, which are islands of smart spaces independent from each other. As users move about, they will have to roam from private smart space to public smart space and vice versa. When they enter a new island of smart space, they will have to setup their devices and service manually to get the same or different services they had at the previous location. Users might be living in a non-pervasive computing environment because this manual operation is inappropriate to its generic features of proactive and intelligent services of pervasive computing. The framework architecture will provide seamless inter space interactions initiated by changes in users' location to acquire negotiations of resources for new and current residents regarding service provision with limited available networked devices.
Physical properties of the HAT-P-23 and WASP-48 planetary systems from multi-colour photometry
Ciceri, S.,Mancini, L.,Southworth, J.,Bruni, I.,Nikolov, N.,D’Ago, G.,Schrö,der, T.,Bozza, V.,Tregloan-Reed, J.,Henning, Th. Springer-Verlag 2015 Astronomy and astrophysics Vol.577 No.-
<P>Context. Accurate and repeated photometric follow-up observations of planetary transit events are important to precisely characterize the physical properties of exoplanets. A good knowledge of the main characteristics of the exoplanets is fundamental in order to trace their origin and evolution. Multi-band photometric observations play an important role in this process. Aims. By using new photometric data, we computed precise estimates of the physical properties of two transiting planetary systems at equilibrium temperatures of ~2000 K. Methods. We present new broadband, multi-colour photometric observations obtained using three small class telescopes and the telescope-defocussing technique. In particular we obtained 11 and 10 light curves covering 8 and 7 transits of HAT-P-23 and WASP48, respectively. For each of the two targets, one transit event was simultaneously observed through four optical filters. One transit of WASP-48b was monitored with two telescopes from the same observatory. The physical parameters of the systems were obtained by fitting the transit light curves with JKTEBOP and from published spectroscopic measurements. Results. We have revised the physical parameters of the two planetary systems, finding a smaller radius for both HAT-P-23?b and WASP48?b, Rb = 1.224 ± 0.037 RJup and Rb = 1.396 ±0.051 RJup, respectively, than those measured in the discovery papers (Rb = 1.368 ± 0.090 RJup and Rb = 1.67 ±0.10 RJup). The density of the two planets are higher than those previously published (ρb ~ 1.1 and ~0.3 ρjup for HAT-P-23 and WASP48, respectively) hence the two hot Jupiters are no longer located in a parameter space region of highly inflated planets. An analysis of the variation of the planet’s measured radius as a function of optical wavelength reveals flat transmission spectra within the experimental uncertainties. We also confirm the presence of the eclipsing contact binary NSVS3071474 in the same field of view of WASP48, for which we refine the value of the period to be 0.459?d.</P>
Dust properties across the CO snowline in the HD 163296 disk from ALMA and VLA observations
Guidi, G.,Tazzari, M.,Testi, L.,de Gregorio-Monsalvo, I.,Chandler, C. J.,Pé,rez, L.,Isella, A.,Natta, A.,Ortolani, S.,Henning, Th.,Corder, S.,Linz, H.,Andrews, S.,Wilner, D.,Ricci, L.,Carpenter, Springer-Verlag 2016 Astronomy and astrophysics Vol.588 No.-
Lim, Shin-Young,Chung, Lawrence,Helal, Sumi,Yang, Hen-I Korean Institute of Intelligent Systems 2009 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.9 No.3
In this paper, design of framework architecture of pervasive computing system providing seamless inter space interactions between private and public smart spaces is presented. The seamless inter space interaction issues are related to establishing user's service environment by allocating relevant resources in a new location where there are no prior settings for the user or where there are current users already being served in the new location. In the realm of pervasive computing, we can have different types of smart spaces, offering proactive and intelligent services, which are islands of smart spaces independent from each other. As users move about, they will have to roam from private smart space to public smart space and vice versa. When they enter a new island of smart space, they will have to setup their devices and service manually to get the same or different services they had at the previous location. Users might be living in a non-pervasive computing environment because this manual operation is inappropriate to its generic features of proactive and intelligent services of pervasive computing. The framework architecture will provide seamless inter space interactions initiated by changes in users' location to acquire negotiations of resources for new and current residents regarding service provision with limited available networked devices.