scholarly journals Short-term variations in Be stars observed by the CoRoT and Kepler space missions

2010 ◽  
Vol 6 (S272) ◽  
pp. 451-456 ◽  
Author(s):  
Juan Gutiérrez-Soto ◽  
Coralie Neiner ◽  
Juan Fabregat ◽  
Antonino Francesco Lanza ◽  
Thierry Semaan ◽  
...  
Keyword(s):  
Active Regions ◽  
Space Missions ◽  
Be Stars ◽  
Short Term ◽  
Long Duration ◽  
Term Variation ◽  
Be Star ◽  
Preliminary Study ◽  
Very High

AbstractThe corot and kepler space missions are collecting very high-precision long-duration photometric data of many Be stars, allowing us to better understand the origin of their short-term variability and the link between these variations and the Be phenomenon. In this paper, we present a brief summary of the results obtained in the analysis of several Be stars observed with corot in terms of pulsations. In addition, we show that variations of the Be star HD 175869 can be explained as two active regions separated by 150 degrees or as unstable pulsating modes in a star with an extensive mixing in radiative layers corresponding to a core overshooting of 0.35Hp. A preliminary study of the photometric and spectroscopic variability seen in the B1.5IVe star HD 51193 is performed. Currently the kepler satellite is observing the only confirmed Be star in its field of view, namely KIC 6954726. From low-resolution spectra we derived a spectral type of B2.5Ve for this star and we studied the long-term variation of the emission in the Hα line. The 3.5-year kepler light curve will allow us to detect even more close frequencies than with corot and to perform a detailed analysis of the amplitude variations in a Be star.

scholarly journals Chinese and Japanese Participation in B/Be Star Campaigns

2000 ◽  
Vol 175 ◽  
pp. 364-371
Author(s):  
J. Hao
Keyword(s):  
Astronomical Observatory ◽  
Be Stars ◽  
Short Term ◽  
Be Star ◽  
Short Term Variability

AbstractIn the early 1980’s, astronomers at the Beijing Astronomical Observatory (BAO) entered a collaboration in a long term photometric observing project on Be stars which included about 30 stars. For example, in 1983 the group at BAO organized a multi-site campaign to measure the short term variability of EW Lac, KX And, KY And, o And, and LQ And. In 1989, 48 Per was selected to be one of the targets of MuSiCoS campaign in which many stellar astronomers at the BAO participated. In 1991, the Be group at the BAO joined a campaign on the prototypical nonradially pulsating B star, 53 Per. In 1992, French & Chinese astronomers proposed a joint campaign on o And and EW Lac. Astronomers in Japan are also active in Be star campaigns and in 1993-5 they organized several campaigns on few well known Be stars (ζ Oph, EW Lac, ϒ Cas, λ Eri and 28 Cyg).

CHANGES IN BLOOD PROTEOME OF COSMONAUTS WITH MICRO- AND MACROVASCULAR INJURIES DUE TO G-LOADS AT THE FINAL STAGE OF LONG-DURATION SPACE MISSIONS

2020 ◽  
Vol 54 (5) ◽  
pp. 5-14
Author(s):  
L.Kh. Pastushkova ◽  
◽  
K.S. Kireev ◽  
I.M. Larina ◽  
◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Soft Tissues ◽  
Blood Rheology ◽  
Landing Site ◽  
Space Missions ◽  
Vascular Injuries ◽  
New Approach ◽  
Long Duration ◽  
Integrated Response

The integrated response of the human proteome to re-entry g-loads following long-term space missions was studied in 13 male cosmonauts at the age of 44 ± 6 years. Examination at the landing site discovered local petechial hemorrhages into soft tissues of the back and lower legs. The paper presents a new approach to evaluation of petechia and soft tissue hemorrhages in cosmonauts on return to Earth. Proteomic analysis was performed with the use of LC-MS. Bioinformation analysis was made using Perseus, PubMed, Uniprot and ANDSystem software. Nine out of 19 significantly different (p < 0.05) proteins were related to vascular injuries directly. We described proteins with a primarily protecting effect against endothelial cells apoptosis and augmentation of vascular permeability, proteins that are responsible for blood rheology and proteins antagonistic to the main triggers of ischeamia-reperfusion injuries of the lungs, liver and other parenchymal organs.

Positive Emotions

2009 ◽  
pp. 12-24 ◽  
Author(s):  
Michael A. Cohn ◽  
Barbara L. Fredrickson
Keyword(s):  
Positive Emotions ◽  
Well Being ◽  
Life Outcomes ◽  
Short Term ◽  
Future Success ◽  
Broaden And Build Theory ◽  
Mental And Physical Health ◽  
Very High ◽  
Future Growth

Positive emotions include pleasant or desirable situational responses, ranging from interest and contentment to love and joy, but are distinct from pleasurable sensation and undifferentiated positive affect. These emotions are markers of people's overall well-being or happiness, but they also enhance future growth and success. This has been demonstrated in work, school, relationships, mental and physical health, and longevity. The broaden-and-build theory of positive emotions suggests that all positive emotions lead to broadened repertoires of thoughts and actions and that broadening helps build resources that contribute to future success. Unlike negative emotions, which are adapted to provide a rapid response to a focal threat, positive emotions occur in safe or controllable situations and lead more diffusely to seeking new resources or consolidating gains. These resources outlast the temporary emotional state and contribute to later success and survival. This chapter discusses the nature of positive emotions both as evolutionary adaptations to build resources and as appraisals of a situation as desirable or rich in resources. We discuss the methodological challenges of evoking positive emotions for study both in the lab and in the field and issues in observing both short-term (“broaden”) and long-term (“build”) effects. We then review the evidence that positive emotions broaden perception, attention, motivation, reasoning, and social cognition and ways in which these may be linked to positive emotions' effects on important life outcomes. We also discuss and contextualize evidence that positive emotions may be detrimental at very high levels or in certain situations. We close by discussing ways in which positive emotions theory can be harnessed by both basic and applied positive psychology research.

scholarly journals Long-Term Microgravity Effects on Isometric Handgrip and Precision Pinch Force with Visual and Proprioceptive Feedback

2018 ◽  
Vol 2018 ◽  
pp. 1-11
Author(s):  
Ilario Puglia ◽  
Michele Balsamo ◽  
Marco Vukich ◽  
Valfredo Zolesi
Keyword(s):  
Maximum Voluntary Contraction ◽  
Space Station ◽  
Voluntary Contraction ◽  
Force Output ◽  
Isometric Handgrip ◽  
Short Term ◽  
Space Flights ◽  
Pinch Force ◽  
Long Duration

The study and analysis of human physiology during short- and long-duration space flights are the most valuable approach in order to evaluate the effect of microgravity on the human body and to develop possible countermeasures in prevision of future exploratory missions and Mars expeditions. Hand performances such as force output and manipulation capacity are fundamental for astronauts’ intra- and extravehicular activities. Previous studies on upper limb conducted on astronauts during short-term missions (10 days) indicated a temporary partial reduction in the handgrip maximum voluntary contraction (MVC) followed by a prompt recovery and adaptation to weightlessness during the last days of the mission. In the present study, we report on the “Crew’s Health: Investigation on Reduced Operability” (CHIRO) protocol, developed for handgrip and pinch force investigations, performed during the six months increment 7 and increment 8 (2003-2004) onboard International Space Station (ISS). We found that handgrip and pinch force performance are reduced during long-term increments in space and are not followed by adaptation during the mission, as conversely reported during short-term increment experiments. The application of protocols developed in space will be eligible to astronauts during long-term space missions and to patients affected by muscle atrophy diseases or nervous system injury on Earth.

scholarly journals Long- and Short-Term Changes of the Structure of Macrophytes in Lake Piaseczno in Relation to Land Use in the Łęczna-Włodawa Lakeland (Poland)

2013 ◽  
Vol 15 (2) ◽  
pp. 101-110
Author(s):  
Joana Sender ◽  
Weronika Maślanko
Keyword(s):  
Land Use ◽  
Aquatic Plants ◽  
Short Term ◽  
Main Interest ◽  
Central European ◽  
Macrophyte Communities ◽  
Long Term Changes ◽  
Very High ◽  
Macrophyte Structure

ABSTRACT The Łęczna-Włodawa Plain, known also as the Łęczna-Wlodawa Lakeland, lies within the territory of the largest subregion of the Polesie region, covering over 1,300 km2. The main interest of the Łęczna-Włodawa Lakeland is that it is the oldest in the Central European Lowlands group of about 68 lakes. Among such a large number of lakes there exist all trophic types. However, since the late 1950’s, enormous dynamics of change associated with the disappearance of oligo- and mesotrophic lakes and their transformation into eutrophic, even hypertrophic, lakes have been observed. One of the biocenotic elements of the lakes, which are indicators of these changes, is aquatic plants. The aim of this study was to determine the macrophyte structure of Piaseczno Lake and changes of land use in its surroundings. Piaseczno Lake still represents very high natural values. A reduction in the number of macrophyte communities, which occurred especially in 2008, was a consequence of the fast-growing recreation infrastructure. From 1976 until 2010 an area of recreation infrastructure in the studied area increased more than 3.5 times, and in the built-up area more than five times, as well as a doubling of the total length of the roads. Meanwhile the surface area of wetlands and peatbogs significantly decreased - more than 11 times. Long-term changes in the structure of the macrophyte communities show that the number of communities has varied in each year, probably as a consequence of changes in landuse. Analysis showed changes to the surfaces inhabited by macrophytes, which have decreased significantly over only four years, by more than 25%. However, the proportion of rush communities has increased.

scholarly journals Satellites, Self-reports, and Submersion: Exposure to Floods in Bangladesh

2015 ◽  
Vol 105 (5) ◽  
pp. 232-236 ◽  
Author(s):  
Raymond Guiteras ◽  
Amir Jina ◽  
A. Mushfiq Mobarak
Keyword(s):  
Climate Change ◽  
Economic Activity ◽  
Climate Change Impacts ◽  
Objective Data ◽  
Short Term ◽  
Temperature And Precipitation ◽  
Flood Exposure ◽  
Self Reports ◽  
Term Variation

A burgeoning “Climate-Economy” literature has uncovered many effects of changes in temperature and precipitation on economic activity, but has made considerably less progress in modeling the effects of other associated phenomena, like natural disasters. We develop new, objective data on floods, focusing on Bangladesh. We show that rainfall and self-reported exposure are weak proxies for true flood exposure. These data allow us to study adaptation, giving accurate measures of both long-term averages and short term variation in exposure. This is important in studying climate change impacts, as people will not only experience new exposures, but also experience them differently.

Radial Velocity Variability of K Giants

1991 ◽  
Vol 130 ◽  
pp. 386-388
Author(s):  
Artie P. Hatzes ◽  
William D. Cochran
Keyword(s):  
Radial Velocity ◽  
Active Regions ◽  
Peak Amplitude ◽  
Short Term ◽  
Rotational Modulation ◽  
Surface Active ◽  
Radial Velocity Data ◽  
Long Term Variations ◽  
K Giants

AbstractAt McDonald Observatory we have been monitoring the relative radial velocities of a sample of K giants. The technique employed uses the telluric O2 lines near 6300 Å as a reference for measuring the stellar line shifts. We demonstrate that precisions of 10 m s−1 are possible with this technique. We present radial velocity data covering a 2 year time span for α Boo, α Tau, and β Gem. All of these stars show both long term variations (~ several hundred days) with a peak-to-peak amplitude of about 400 m s−1 and short term variations (~ few days) with a peak-to-peak amplitude of about 100 m s−1. The long term variations may be due to the rotational modulation of surface active regions whereas the short term variations may be indicative of pulsations.

scholarly journals The Long-term Variation in the RV Tauri Star U Mon

1995 ◽  
Vol 155 ◽  
pp. 409-410 ◽  
Author(s):  
Karen R. Pollard ◽  
P. L. Cottrell
Keyword(s):  
High Resolution ◽  
Light Curve ◽  
Radial Velocity ◽  
Tauri Star ◽  
Short Term ◽  
Instability Strip ◽  
Term Variation ◽  
Velocity Variations

The RV Tauri stars are semiregular pulsating variables located in the brightest part of the Cepheid II instability strip. They have a characteristic light curve of alternating deep and shallow minima. A subset of the RV Tauri stars (the RVb subclass) exhibit long-term (500 to 2600 day) light and radial velocity variations. Although it is well established that the short-term variations are due to pulsations, the long-term behaviour is not well understood.BVRI photometry and high-resolution spectra of U Mon (the brightest member of the RVb subclass) were obtained at the Mt John University Observatory (MJUO) between 1990 Aug and 1994 May. The light and colour curves obtained clearly show the long-term variation in U Mon (Fig. 1(a) and (b)). The reddest colours occur slightly later than the long-term minimum in the light curve. The short-term light and colour variations are ‘damped’ at the long-term minimum.

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