A Systematic Characterization of the HR8799 System with GRAVITY

2021 ◽  
Author(s):  
Evert Nasedkin ◽  
Paul Molliere ◽  
Keyword(s):  
Data Processing ◽  
Wavelength Range ◽  
Planet Formation ◽  
State Of The Art ◽  
Planetary Atmospheres ◽  
Formation History ◽  
History Of ◽  
Molecular Abundances ◽  
Insight Into

<p>The four planets of the HR8799 system provide a benchmark for directly imaged exoplanets. As these planets share a formation history, variations between the planet’s atmospheric properties - likely tracing their individual formation pathways - could provide insight into the details of the process of planet formation. In order explore these atmospheres and their evolution, we use new data obtained with the GRAVITY instrument at the VLTI as part of the ExoGRAVITY campaign, combined with data from SPHERE, GPI, CHARIS, ALES and OSIRIS in order to provide the best picture of the planetary atmospheres across a broad wavelength range. Using petitRADTRANS in a Bayesian retrieval framework, we compare a suite of state-of-the-art models applied to each of the targets in order to measure atmospheric properties such as metallicity, molecular abundances, and the C/O ratio, which is a well known tracer of the formation history. In this talk I will describe the data processing and modelling efforts which allow us to peer into the atmospheres of the HR8799 planets, and will outline the steps needed to tie the newly retrieved planetary properties to the formation history of the system.</p>

Neither Eyewitnesses, Nor Windows to the Past, but Valuable Testimony in its Own Right: Remarks on Iconography, Source Criticism and Ancient Data-processing

2007 ◽  
Author(s):  
CHRISTOPH UEHLINGER
Keyword(s):  
Data Processing ◽  
Conceptual Framework ◽  
Visual Art ◽  
State Of The Art ◽  
Case Examples ◽  
The Past ◽  
Ancient Israel ◽  
History Of ◽  
Alternative Approaches ◽  
Potential Use

This chapter explores the potential use of visual sources, together with the methods employed for studying them, such as iconography or iconology, for the history of ‘ancient Israel’. It describes the theoretical and conceptual framework, particularly the notion of ‘eyewitnessing’, and considers the method, particularly iconography. The chapter also presents case examples chosen from monuments which are so well known to historians of ancient Israel that they are well suited to illustrate both the pitfalls of more conventional interpretations and the potential of alternative approaches. Before turning to the sources – namely visual evidence that may be related to the history of ancient Israel and Judah – the chapter discusses the state of the art among fellow historians in neighbouring disciplines, including those belonging to the so-called ‘humanities’ (or arts and letters). It also considers visual art and history, the metaphor of legal investigation, the balancing of testimony, and the particular status of an eyewitness.

The amphibamiform Nanobamus macrorhinus from the early Permian of Texas

2019 ◽  
Vol 94 (2) ◽  
pp. 366-377 ◽  
Author(s):  
Bryan M. Gee ◽  
Robert R. Reisz
Keyword(s):  
Phylogenetic Analysis ◽  
Evolutionary History ◽  
Phylogenetic Position ◽  
Early Permian ◽  
Larval Form ◽  
Terrestrial Environments ◽  
History Of ◽  
Insight Into

AbstractNanobamus macrorhinus Schoch and Milner, 2014 is a small amphibamiform temnospondyl from the early Permian Arroyo Formation of Texas. It is most readily characterized by an elongate and partially subdivided naris. This condition is superficially reminiscent of that seen in the coeval trematopids, the group to which N. macrorhinus was originally referred to under an interpretation of the holotype as a larval form. This was discounted by later workers, but the amphibamiform affinities of the specimen were not formalized until recently. The specimen has never been described in the context of its amphibamiform affinities and remains poorly characterized, never having been sampled in a phylogenetic analysis. Here we present a complete, updated osteological description of N. macrorhinus, including an improved characterization of its unique mosaic of plesiomorphic and apomorphic features and clarification of the taxon's autapomorphies. Our analysis of the taxon's phylogenetic position within Amphibamiformes shows that N. macrorhinus was recovered as diverging after basal amphibamiforms, e.g., the micropholids, and before derived amphibamiforms, e.g., the amphibamids. This is supported by the unique mixture of retained plesiomorphies, e.g., nonforeshortened postparietals and an oval choana, and apomorphies, e.g., a narrow interorbital region and slender palatal rami of the pterygoid. These results reflect the complexity of terrestrial amphibamiform diversity and provide further insight into the evolutionary history of the lissamphibian stem in terrestrial environments.

The Strel’tsovka uranium district: Isotopic geochronological (U-Pb, Rb-Sr, Sm-Nd) characterization of granitoids and their place in the formation history of uranium deposits

2010 ◽  
Vol 52 (6) ◽  
pp. 496-513 ◽  
Author(s):  
V. N. Golubev ◽  
I. V. Chernyshev ◽  
A. B. Kotov ◽  
E. B. Sal’nikova ◽  
Yu. V. Golzman ◽  
...  
Keyword(s):  
Uranium Deposits ◽  
Formation History ◽  
History Of

scholarly journals Connecting planet formation and astrochemistry

2019 ◽  
Vol 632 ◽  
pp. A63 ◽  
Author(s):  
Alex J. Cridland ◽  
Ewine F. van Dishoeck ◽  
Matthew Alessi ◽  
Ralph E. Pudritz
Keyword(s):  
Solar System ◽  
Planet Formation ◽  
Water Ice ◽  
Hot Jupiters ◽  
Formation History ◽  
General Mass ◽  
Exoplanetary Atmospheres ◽  
Molecular Abundances ◽  
Gas Accretion ◽  
Oxygen Ratio

To understand the role that planet formation history has on the observable atmospheric carbon-to-oxygen ratio (C/O) we have produced a population of astrochemically evolving protoplanetary disks. Based on the parameters used in a pre-computed population of growing planets, their combination allows us to trace the molecular abundances of the gas that is being collected into planetary atmospheres. We include atmospheric pollution of incoming (icy) planetesimals as well as the effect of refractory carbon erosion noted to exist in our own solar system. We find that the carbon and oxygen content of Neptune-mass planets are determined primarily through solid accretion and result in more oxygen-rich (by roughly two orders of magnitude) atmospheres than hot Jupiters, whose C/O are primarily determined by gas accretion. Generally we find a “main sequence” between the fraction of planetary mass accreted through solid accretion and the resulting atmospheric C/O; planets of higher solid accretion fraction have lower C/O. Hot Jupiters whose atmospheres have been chemically characterized agree well with our population of planets, and our results suggest that hot-Jupiter formation typically begins near the water ice line. Lower mass hot Neptunes are observed to be much more carbon rich (with 0.33 ≲ C/O ≲ 1) than is found in our models (C/O ~ 10−2), and suggest that some form of chemical processing may affect their observed C/O over the few billion years between formation and observation. Our population reproduces the general mass-metallicity trend of the solar system and qualitatively reproduces the C/O metallicity anti-correlation that has been inferred for the population of characterized exoplanetary atmospheres.

THE LEGAL CHARACTERIZATION OF THE INSURANCE CONTRACT

2017 ◽  
pp. 204
Author(s):  
Olīvija Tuvi ◽  
Līga Mazure
Keyword(s):  
National Economy ◽  
Basic Needs ◽  
Modern Society ◽  
Insurance Contract ◽  
Sense Of Security ◽  
Compulsory Insurance ◽  
History Of ◽  
Ancient Times ◽  
Insight Into

Human feeling of security is one of the basic needs, so the idea of insurance is already perceived in ancient times. Nowadays the importance of insurance increases, because it is an essential part of national economy, as well as one of the modern society level determinants, because it even provides compulsory insurance to protect important interests. Insurance creates a sense of security in the increasing number of spheres of life, which continues to expand, providing more and more new insurance objects. This work provides insight into history of the idea of insurance contract and summarizes different ideas and problems about the insurance contract and its types.

Natural History of Disseminated Coccidioidomycosis: Examination of the Veterans Affairs–Armed Forces Database

2020 ◽  
Author(s):  
Derek J Bays ◽  
George R Thompson ◽  
Susan Reef ◽  
Linda Snyder ◽  
Alana J Freifeld ◽  
...  
Keyword(s):  
Natural History ◽  
Pulmonary Nodules ◽  
Armed Forces ◽  
Veterans Affairs ◽  
Initial Infection ◽  
All Cause Mortality ◽  
History Of ◽  
Insight Into

Abstract Background The natural history of non–central nervous system (non-CNS) disseminated coccidioidomycosis (DCM) has not been previously characterized. The historical Veterans Affairs (VA)–Armed Forces coccidioidomycosis patient group provides a unique cohort of patients not treated with standard antifungal therapy, allowing for characterization of the natural history of coccidioidomycosis. Methods We conducted a retrospective study of 531 VA–Armed Forces coccidioidomycosis patients diagnosed between 1955–1958 and followed to 1966. Groups were identified as non-DCM (462 patients), DCM (44 patients), and CNS (25 patients). The duration of the initial infection, fate of the primary infection, all-cause mortality, and mortality secondary to coccidioidomycosis were assessed and compared between groups. Results Mortality due to coccidioidomycosis at the last known follow-up was significantly different across the groups: 0.65% in the non-DCM group, 25% in the DCM group, and 88% in the CNS group (P < .001). The primary fate of pulmonary infection demonstrated key differences, with pulmonary nodules observed in 39.61% of the non-DCM group, 13.64% of the DCM group, and 20% of the CNS group (P < .001). There were differences in cavity formation, with 34.20% in the non-DCM group, 9.09% in the DCM group, and 8% in the CNS group (P < .001). Dissemination was the presenting manifestation or was concurrent with the initial infection in 41% and 56% of patients in the non-CNS DCM and CNS groups, respectively. Conclusions This large, retrospective cohort study helps characterize the natural history of DCM, provides insight into the host immunologic response, and has direct clinical implications for the management and follow-up of patients.

scholarly journals Studies of Speech Disorders in Schizophrenia. History and State-of-the-art

2015 ◽  
Vol 20 (2) ◽  
pp. 78-93 ◽  
Author(s):  
E.F. Shvedovskiy ◽  
N.V. Zvereva
Keyword(s):  
Multidisciplinary Approach ◽  
State Of The Art ◽  
Biological Psychiatry ◽  
Speech Disorders ◽  
Speech Pathology ◽  
Integrated Research ◽  
History Of ◽  
Perspective Analysis ◽  
Genetic Trends

The article reviews studies of speech disorders in schizophrenia. The authors paid attention to a historical course and characterization of studies of areas: the actual psychopathological (speech disorders as a psychopathological symptoms, their description and taxonomy), psychological (isolated neurons and pathopsychological perspective analysis) separately analyzed some modern foreign works, covering a variety of approaches to the study of speech disorders in the endogenous mental disorders. Disorders and features of speech are among the most striking manifestations of schizophrenia along with impaired thinking (Savitskaya A. V., Mikirtumov B. E.). With all the variety of symptoms, speech disorders in schizophrenia could be classified and organized. The few clinical psychological studies of speech activity in schizophrenia presented work on the study of generation and standard speech utterance; features verbal associative process, speed parameters of speech utterances. Special attention is given to integrated research in the mainstream of biological psychiatry and genetic trends. It is shown that the topic for more than a half-century history of originality of speech pathology in schizophrenia has received some coverage in the psychiatric and psychological literature and continues to generate interest in the modern integrated multidisciplinary approach.

scholarly journals Mapping young stellar populations towards Orion with Gaia DR1

2017 ◽  
Vol 12 (S330) ◽  
pp. 197-200
Author(s):  
Eleonora Zari ◽  
Anthony G. A. Brown
Keyword(s):  
Star Formation ◽  
Interstellar Medium ◽  
Stellar Population ◽  
Star Formation History ◽  
Population Spread ◽  
Formation History ◽  
History Of ◽  
Ob Associations ◽  
Insight Into ◽  
Age Estimates

AbstractOB associations are prime sites for the study of star formation processes and of the interaction between young massive stars with the interstellar medium. Furthermore, the kinematics and structure of the nearest OB associations provide detailed insight into the properties and origin of the Gould Belt. In this context, the Orion complex has been extensively studied. However, the spatial distribution of the stellar population is still uncertain: in particular, the distances and ages of the various sub-groups composing the Orion OB association, and their connection to the surrounding interstellar medium, are not well determined. We used the first Gaia data release to characterize the stellar population in Orion, with the goal to obtain new distance and age estimates of the numerous stellar groups composing the Orion OB association. We found evidence of the existence of a young and rich population spread over the entire region, loosely clustered around some known groups. This newly discovered population of young stars provides a fresh view of the star formation history of the Orion region.

scholarly journals Topical problems in the theory of planet formation: formation of planetesimals

2019 ◽  
pp. 104-121
Author(s):  
A. B. Makalkin ◽  
I. N. Ziglina ◽  
M. E. Artyushkova
Keyword(s):  
Planet Formation ◽  
State Of The Art ◽  
The State ◽  
Special Focus ◽  
Formation Theory ◽  
History Of Development ◽  
The Earth ◽  
History Of ◽  
Academy Of Sciences ◽  
Schmidt Institute

The development of the Earth’s and planets formation theory over 70 years is considered with a special focus on the history of development of this theory at the Schmidt Institute of Physics of the Earth of the Russian Academy of Sciences (IPE RAS) where this direction of research was founded by Otto Schmidt. The state of the art of the theory is outlined. In particular, the planetesimals formation problem currently belonging to the key unsolved issues in the theory of planet formation is discussed. Recent results of the studies aimed at solving this problem at IPE RAS are presented.

40Ar/39Ar Dating and Characterization of Hornblende from the Nelson Plutonic Suite, Southern Kootenay Arc, SE B.C.

2018 ◽  
Author(s):  
Jessica Pickett
Keyword(s):  
Thermal History ◽  
Microprobe Analysis ◽  
The West ◽  
Wide Range ◽  
Dating Methods ◽  
History Of ◽  
Higher Temperature ◽  
Insight Into ◽  
Scanning Electron

The Kootenay Arc located in SE B.C. has experienced more than one episode of tectonism, metamorphism and plutonism. The Mid-Jurassic to Eocene thermal history of the area has been investigated using K-Ar and 40/39 dating methods of biotite and muscovite; however there are no reliable hornblende dates from this area. This study will investigate two easterly stocks of the Nelson Plutonic Suite, the Mine and Wall stocks. Both of these have U-Pb zircon ages between 171 and 168 Ma but record a wide range of mica cooling and overprinting dates between 166 Ma in the west and 67 Ma in the east. 40Ar/39Ar age spectra for hornblende from 11 rocks in these stocks comprising a transect of the area, will aid in defining the higher temperature part of the thermal history. Previous attempts to prepare bulk hornblende separates were unsuccessful due to overgrowths and intergrowths of biotite, chlorite, plagioclase and K-feldspar. Part of this study involves testing the efficiency of SELFRAG disaggregation, which uses pulses of electrostatic power to break apart the biotite-hornblende-epidote granodiorite along mineral cleavage planes and grain boundaries. This should lead to higher purity mineral separates and better dates. Scanning Electron Microscopy (SEM) and Microprobe analysis analyse the separates looking for K-rich inclusions and the hornblendes variation in chemistry. Ca/K ratios are typical of igneous amphibole. Combined with previous K-Ar and 40/39 results for micas these hornblende dates should provide some insight into the history of the Next Creek fault and the thermotectonic history of the area.

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