scholarly journals HDO and SO2 thermal mapping on Venus

2019 ◽  
Vol 623 ◽  
pp. A70 ◽  
Author(s):  
T. Encrenaz ◽  
T. K. Greathouse ◽  
E. Marcq ◽  
H. Sagawa ◽  
T. Widemann ◽  
...  
Keyword(s):  
Local Time ◽  
Mixing Ratio ◽  
Echelle Spectrograph ◽  
Imaging Spectrometer ◽  
Infrared Telescope ◽  
Telescope Facility ◽  
The Individual ◽  
Line Depth ◽  
Uv Range

Since January 2012 we have been monitoring the behavior of sulfur dioxide and water on Venus, using the Texas Echelon Cross-Echelle Spectrograph (TEXES) imaging spectrometer at the NASA InfraRed Telescope Facility (IRTF, Mauna Kea Observatory). We present here the observations obtained between January 2016 and September 2018. As in the case of our previous runs, data were recorded around 1345 cm−1 (7.4 μm). The molecules SO2, CO2, and HDO (used as a proxy for H2O) were observed, and the cloudtop of Venus was probed at an altitude of about 64 km. The volume mixing ratio of SO2 was estimated using the SO2/CO2 line depth ratios of weak transitions; the H2O volume mixing ratio was derived from the HDO/CO2 line depth ratio, assuming a D/H ratio of 200 times the Vienna Standard Mean Ocean Water (VSMOW). As reported in our previous analyses, the SO2 mixing ratio shows strong variations with time and also over the disk, showing evidence of the formation of SO2 plumes with a lifetime of a few hours; in contrast, the H2O abundance is remarkably uniform over the disk and shows moderate variations as a function of time. We performed a statistical analysis of the behavior of the SO2 plumes, using all TEXES data between 2012 and 2018. They appear mostly located around the equator. Their distribution as a function of local time seems to show a depletion around noon; we do not have enough data to confirm this feature definitely. The distribution of SO2 plumes as a function of longitude shows no clear feature, apart from a possible depletion around 100E–150E and around 300E–360E. There seems to be a tendency for the H2O volume mixing ratio to decrease after 2016, and for the SO2 mixing ratio to increase after 2014. However, we see no clear anti-correlation between the SO2 and H2O abundances at the cloudtop, neither on the individual maps nor over the long term. Finally, there is a good agreement between the TEXES results and those obtained in the UV range (SPICAV/Venus Express and UVI/Akatsuki) at a slightly higher altitude. This agreement shows that SO2 observations obtained in the thermal infrared can be used to extend the local time coverage of the SO2 measurements obtained in the UV range.

scholarly journals HDO and SO2 thermal mapping on Venus

2020 ◽  
Vol 639 ◽  
pp. A69 ◽  
Author(s):  
T. Encrenaz ◽  
T. K. Greathouse ◽  
E. Marcq ◽  
H. Sagawa ◽  
T. Widemann ◽  
...  
Keyword(s):  
Local Time ◽  
Mixing Ratio ◽  
Echelle Spectrograph ◽  
Imaging Spectrometer ◽  
Infrared Telescope ◽  
Depth Ratio ◽  
Time Period ◽  
Telescope Facility ◽  
Line Depth

Since January 2012, we have been monitoring the behavior of sulfur dioxide and water on Venus, using the Texas Echelon Cross-Echelle Spectrograph imaging spectrometer at the NASA InfraRed Telescope Facility (IRTF, Mauna Kea Observatory). Here, we present new data recorded in February and April 2019 in the 1345 cm−1 (7.4 μm) spectral range, where SO2, CO2, and HDO (used as a proxy for H2O) transitions were observed. The cloud top of Venus was probed at an altitude of about 64 km. As in our previous studies, the volume mixing ratio (vmr) of SO2 was estimated using the SO2/CO2 line depth ratio of weak transitions; the H2O volume mixing ratio was derived from the HDO/CO2 line depth ratio, assuming a D/H ratio of 200 times the Vienna standard mean ocean water. As reported in our previous analyses, the SO2 mixing ratio shows strong variations with time and also over the disk, showing evidence for the formation of SO2 plumes with a lifetime of a few hours; in contrast, the H2O abundance is remarkably uniform over the disk and shows moderate variations as a function of time. We have used the 2019 data in addition to our previous dataset to study the long-term variations of SO2 and H2O. The data reveal a long-term anti-correlation with a correlation coefficient of −0.80; this coefficient becomes −0.90 if the analysis is restricted to the 2014–2019 time period. The statistical analysis of the SO2 plumes as a function of local time confirms our previous result with a minimum around 10:00 and two maxima near the terminators. The dependence of the SO2 vmr with respect to local time shows a higher abundance at the evening terminator with respect to the morning. The dependence of the SO2 vmr with respect to longitude exhibits a broad maximum at 120–200° east longitudes, near the region of Aphrodite Terra. However, this trend has not been observed by other measurements and has yet to be confirmed.

scholarly journals Binary energy source of the HH 250 outflow and its circumstellar environment

2018 ◽  
Vol 612 ◽  
pp. A73 ◽  
Author(s):  
Fernando Comerón ◽  
Bo Reipurth ◽  
Hsi-Wei Yen ◽  
Michael S. Connelley
Keyword(s):  
Adaptive Optics ◽  
Dust Emission ◽  
Circumstellar Disks ◽  
Spectral Energy ◽  
Multiple Systems ◽  
Infrared Telescope ◽  
Very Large Telescope ◽  
Telescope Facility ◽  
The Individual ◽  
Circumstellar Environment

Aims. Herbig-Haro flows are signposts of recent major accretion and outflow episodes. We aim to determine the nature and properties of the little-known outflow source HH 250-IRS, which is embedded in the Aquila clouds. Methods. We have obtained adaptive optics-assisted L-band images with the NACO instrument on the Very Large Telescope (VLT), together with N- and Q-band imaging with VISIR also on the VLT. Using the SINFONI instrument on the VLT we carried out H- and K-band integral field spectroscopy of HH 250-IRS, complemented with spectra obtained with the SpeX instrument at the InfraRed Telescope Facility (IRTF) in the JHKL bands. Finally, the SubMillimeter Array (SMA) interferometer was used to study the circumstellar environment of HH 250-IRS at 225 and 351 GHz with CO (2–1) and CO (3–2) maps and 0.9 mm and 1.3 mm continuum images. Results. The HH 250-IRS source is resolved into a binary with 0.′′53 separation, corresponding to 120 AU at the adopted distance of 225 pc. The individual components show heavily veiled spectra with weak CO absorption indicative of late-type stars. Both are Class I sources, but their spectral energy distributions between 1.5 μm and 19 μm differ markedly and suggest the existence of a large cavity around one of the components. The millimeter interferometric observations indicate that the gas mainly traces a circumbinary envelope or disk, while the dust emission is dominated by one of the circumstellar envelopes. Conclusions. HH 250-IRS is a new addition to the handful of multiple systems where the individual stellar components, the circumstellar disks and a circumbinary disk can be studied in detail, and a rare case among those systems in which a Herbig-Haro flow is present.

scholarly journals Precise Near-Infrared Radial Velocities

2015 ◽  
Vol 10 (S314) ◽  
pp. 286-287
Author(s):  
Peter Plavchan ◽  
Peter Gao ◽  
Jonathan Gagne ◽  
Elise Furlan ◽  
Carolyn Brinkworth ◽  
...  
Keyword(s):  
Radial Velocity ◽  
Near Infrared ◽  
M Dwarfs ◽  
Gas Cell ◽  
Methane Absorption ◽  
Infrared Telescope ◽  
Telescope Facility ◽  
Nasa Infrared Telescope Facility ◽  
Modeling Code

AbstractWe present the results of two 2.3 μm near-infrared (NIR) radial velocity (RV) surveys to detect exoplanets around 36 nearby and young M dwarfs. We use the CSHELL spectrograph (R ~ 46,000) at the NASA InfraRed Telescope Facility (IRTF), combined with an isotopic methane absorption gas cell for common optical path relative wavelength calibration. We have developed a sophisticated RV forward modeling code that accounts for fringing and other instrumental artifacts present in the spectra. With a spectral grasp of only 5 nm, we are able to reach long-term radial velocity dispersions of ~20–30 m s−1 on our survey targets.

scholarly journals The H 3 + ionosphere of Uranus: decades-long cooling and local-time morphology

2019 ◽  
Vol 377 (2154) ◽  
pp. 20180408 ◽  
Author(s):  
Henrik Melin ◽  
L. N. Fletcher ◽  
T. S. Stallard ◽  
S. Miller ◽  
L. M. Trafton ◽  
...  
Keyword(s):  
Local Time ◽  
Near Infrared ◽  
Molecular Ions ◽  
Upper Atmosphere ◽  
Infrared Observations ◽  
Infrared Telescope ◽  
Telescope Facility ◽  
Nasa Infrared Telescope Facility ◽  
Cooling Trend

The upper atmosphere of Uranus has been observed to be slowly cooling between 1993 and 2011. New analysis of near-infrared observations of emission from H 3 + obtained between 2012 and 2018 reveals that this cooling trend has continued, showing that the upper atmosphere has cooled for 27 years, longer than the length of a nominal season of 21 years. The new observations have offered greater spatial resolution and higher sensitivity than previous ones, enabling the characterization of the H 3 + intensity as a function of local time. These profiles peak between 13 and 15 h local time, later than models suggest. The NASA Infrared Telescope Facility iSHELL instrument also provides the detection of a bright H 3 + signal on 16 October 2016, rotating into view from the dawn sector. This feature is consistent with an auroral signal, but is the only of its kind present in this comprehensive dataset. This article is part of a discussion meeting issue ‘Advances in hydrogen molecular ions: H 3 + , H 5 + and beyond’.

The Acceptance of Party Unity in Parliamentary Democracies

2017 ◽  
Author(s):  
David M. Willumsen
Keyword(s):  
Political Parties ◽  
Costs And Benefits ◽  
Parliamentary Democracies ◽  
Survey Questions ◽  
Ideal Policy ◽  
Central Argument ◽  
The Individual ◽  
Policy Incentives

The central argument of this book is that voting unity in European legislatures is not primarily the result of the ‘disciplining’ power of the leadership of parliamentary parties, but rather the result of a combination of ideological homogeneity through self-selection into political parties and the calculations of individual legislators about their own long-term benefits. Despite the central role of policy preferences in the subsequent behaviour of legislators, preferences at the level of the individual legislator have been almost entirely neglected in the study of parliaments and legislative behaviour. The book measures these using an until now under-utilized resource: parliamentary surveys. Building on these, the book develops measures of policy incentives of legislators to dissent from their parliamentary parties, and show that preference similarity amongst legislators explains a very substantial proportion of party unity, yet alone cannot explain all of it. Analysing the attitudes of legislators to the demands of party unity, and what drives these attitudes, the book argues that what explains the observed unity (beyond what preference similarity would explain) is the conscious acceptance by MPs that the long-term benefits of belonging to a united party (such as increased influence on legislation, lower transaction costs, and better chances of gaining office) outweigh the short-terms benefits of always voting for their ideal policy outcome. The book buttresses this argument through the analysis of both open-ended survey questions as well as survey questions on the costs and benefits of belonging to a political party in a legislature.

scholarly journals Title I: Modernizing Definitions and Programs Under the Administration on Aging

2020 ◽  
Vol 4 (Supplement_1) ◽  
pp. 714-715
Author(s):  
Marie Gualtieri
Keyword(s):  
Title I ◽  
Adult Population ◽  
Term Care ◽  
Older Americans ◽  
Aging Society ◽  
Program Adaptation ◽  
Older Americans Act ◽  
The Individual ◽  
Older Adult Population

Abstract The recent reauthorization of the Older Americans Act adds language and definitions to current issues facing the aging population. Specifically, Title I includes definitions related to program adaptation and coordination, workforce and long-term care issues, nutrition and social isolation, as well as family caregivers. Different from the last authorization, these definitions span beyond the individual experience to include other entities impacted by an aging society, such as the workforce and families. Overall, the Title I reauthorization seeks to modernize policy to reflect the current influx of the older adult population and its consequences.

scholarly journals Housing adaptations and housing accessibility problems among older adults with long-standing spinal cord injury

2020 ◽  
pp. 030802262097951
Author(s):  
Lizette Norin ◽  
Björn Slaug ◽  
Maria Haak ◽  
Susanne Iwarsson
Keyword(s):  
Older Adults ◽  
Spinal Cord ◽  
Spinal Cord Injuries ◽  
Occupational Performance ◽  
Environmental Barriers ◽  
Cord Injury ◽  
Long Term Follow Up ◽  
Societal Level ◽  
The Individual

Introduction Adults with spinal cord injuries are living longer than previously, and a majority are living in ordinary housing in the community. Housing accessibility is important for maintaining independent occupational performance for this population, but knowledge in this area is insufficient. We investigated housing adaptations and current accessibility problems among older adults with long-standing (>10 years) spinal cord injuries. Method Data from home visits among 122 older adults with spinal cord injuries in Sweden were used. Housing adaptations and environmental barriers were descriptively analysed. Findings Kitchens, entrances, and hygiene areas were common locations for housing adaptations and environmental barriers that generated accessibility problems. The most common adaptations were ramps, wheelchair-accessible stovetops, and ceiling-lifts. Wall-mounted cupboards and high shelves (kitchen), inaccessible storage areas (outside the dwelling), and a lack of grab bars (hygiene area) generated the most accessibility problems. Conclusion Despite housing adaptations, there are considerable accessibility problems in the dwellings of older adults with long-standing spinal cord injuries in Sweden, indicating that long-term follow-up of the housing situation of this population is necessary. Focusing on accessible housing as a prerequisite for occupational performance is at the core of occupational therapy, deserving attention on the individual as well as the societal level.

scholarly journals Genetic Susceptibility to Periodontal Disease in Down Syndrome: A Case-Control Study

2021 ◽  
Vol 22 (12) ◽  
pp. 6274
Author(s):  
María Fernández ◽  
Alicia de de Coo ◽  
Inés Quintela ◽  
Eliane García ◽  
Márcio Diniz-Freitas ◽  
...  
Keyword(s):  
Down Syndrome ◽  
Metabolic Pathways ◽  
Nominal Significance ◽  
Severe Periodontitis ◽  
Gene Level ◽  
Individual Marker ◽  
The Individual ◽  
Control Study ◽  
Marker Level

Severe periodontitis is prevalent in Down syndrome (DS). This study aimed to identify genetic variations associated with periodontitis in individuals with DS. The study group was distributed into DS patients with periodontitis (n = 50) and DS patients with healthy periodontium (n = 36). All samples were genotyped with the “Axiom Spanish Biobank” array, which contains 757,836 markers. An association analysis at the individual marker level using logistic regression, as well as at the gene level applying the sequence kernel association test (SKAT) was performed. The most significant genes were included in a pathway analysis using the free DAVID software. C12orf74 (rs4315121, p = 9.85 × 10−05, OR = 8.84), LOC101930064 (rs4814890, p = 9.61 × 10−05, OR = 0.13), KBTBD12 (rs1549874, p = 8.27 × 10−05, OR = 0.08), PIWIL1 (rs11060842, p = 7.82 × 10−05, OR = 9.05) and C16orf82 (rs62030877, p = 8.92 × 10−05, OR = 0.14) showed a higher probability in the individual analysis. The analysis at the gene level highlighted PIWIL, MIR9-2, LHCGR, TPR and BCR. At the signaling pathway level, PI3K-Akt, long-term depression and FoxO achieved nominal significance (p = 1.3 × 10−02, p = 5.1 × 10−03, p = 1.2 × 10−02, respectively). In summary, various metabolic pathways are involved in the pathogenesis of periodontitis in DS, including PI3K-Akt, which regulates cell proliferation and inflammatory response.

scholarly journals Corruption, Taxation and the Impact on the Shadow Economy

Economies ◽  
2021 ◽  
Vol 9 (1) ◽  
pp. 18 ◽  
Author(s):  
Daniel Němec ◽  
Eva Kotlánová ◽  
Igor Kotlán ◽  
Zuzana Machová
Keyword(s):  
Tax Evasion ◽  
Capital Accumulation ◽  
Shadow Economy ◽  
Labour Force ◽  
Destructive Effect ◽  
Eu Member States ◽  
Initial Assumption ◽  
The Individual ◽  
The Impact

While assessing the economic impacts of corruption, the corruption-related transmission channels which influence taxation as such have to be duly considered. Taking the example of the Czech Republic, this article aims to evaluate the impacts corruption has on the size of the shadow economy as well as on the individual sources of long-term economic growth, making use of a transmission channel through which corruption affects the tax burden components. Using the method of an extended DSGE model, it confirms the initial assumption that an increase in perceived corruption supports the shadow economy’s growth, but at the same time, it demonstrates that corruption and especially its perception has a significantly different effect on two key areas—the capital accumulation and the labour force size. It further identifies another sector of the economy representing taxes which are prone to tax evasion while asserting that corruption has a much more destructive effect on this sector of the economy, offering generalized implications for other post-communist EU member states in a similar situation.

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