scholarly journals Solar rotational cycle in lightning activity in Japan during the 18–19th centuries

2018 ◽  
Vol 36 (2) ◽  
pp. 633-640 ◽  
Author(s):  
Hiroko Miyahara ◽  
Ryuho Kataoka ◽  
Takehiko Mikami ◽  
Masumi Zaiki ◽  
Junpei Hirano ◽  
...  
Keyword(s):  
Solar Activity ◽  
Solar Rotation ◽  
Galactic Cosmic Rays ◽  
Activity Level ◽  
Lightning Activity ◽  
Activity Levels ◽  
Rotational Period ◽  
Solar Activity Level ◽  
The Impact

Abstract. Thunderstorm and cloud activities sometimes show a 27-day period, and this has long been studied to uncover a possible important link to solar rotation. Because the 27-day variations in the solar forcing parameters such as solar ultraviolet and galactic cosmic rays become more prominent when the solar activity is high, it is expected that the signal of the 27-day period in meteorological phenomena may wax and wane according to the changes in the solar activity level. In this study, we examine in detail the intensity variations in the signal of the 27-day solar rotational period in thunder and lightning activity from the 18th to the 19th centuries based on 150-year-long records found in old diaries kept in Japan and discuss their relation with the solar activity levels. Such long records enable us to examine the signals of solar rotation at both high and low solar activity levels. We found that the signal of the solar rotational period in the thunder and lightning activity increases as the solar activity increases. In this study, we also discuss the possibility of the impact of the long-term climatological conditions on the signals of the 27-day period in thunder/lightning activities. Keywords. Meteorology and atmospheric dynamics (lightning)

The Drugs and Natural Antioxidants as the Components of Anti-radiation Countermeasures during Cosmic Flights

2017 ◽  
pp. 66-73 ◽  
Author(s):  
И. Ушаков ◽  
I. Ushakov ◽  
М. Васин ◽  
M. Vasin
Keyword(s):  
Solar Activity ◽  
Cosmic Rays ◽  
Radiation Effects ◽  
High Energy ◽  
Galactic Cosmic Rays ◽  
Stress Factors ◽  
Solar Cosmic Rays ◽  
Post Radiation ◽  
The Impact

Radiation situation for cosmonauts over long-term cosmic flights is caused by low-rate radiation of galactic cosmic rays and solar cosmic rays consisting of high-energy proton as well as heavy particles (Z>10) within 1-2 % that is exclusively a threat of stochastic radiation effects (small increase of cancer risk and decrease of mean life span) for men. During interplanetary expedition periods the small probability of raised solar activity there is a threat of exposure to astronauts at doses that cause deterministic radiation effects leading to the development of the disease as a clinical manifestation of radiation injuries,. In a similar scenario it is necessary to have available to cosmic ship anti-radiation countermeasures for cosmonaut protection. Among radioprotective equipment can be provided with radiation protective agents and partial shielding of body separate section providing the best condition for post-radiation repair of radiosensitive body tissues. Preparation B-190 (indralin) is the most perspective from a small numbers of other radioprotectors permitting for men administration. Besides high radioprotective efficacy and large broadness of protective action B-190 is well tolerated including the impact of extrem flight factors. Antiemetic agent latran (ondansetron) is most interesting among preparation for prophylaxis and reduction of prodromal radiation reaction. To accelerate post-radiation hematopoietic recovery after raised solar activity an administration of radiomitigators (riboxin et al.) is substantiated. Neupomax (neupogen) is recommended as a preparation for pathogenesis therapy of acute radiation syndrome. Possible consequences of long-term cosmic voyages for oxidative stress development are taken into consideration. On their basis of nNatural antioxidants, preparations and nutrients radiomodulators, fully qualitative nutrition including vegetable food enriched flavonoids, vitamins C, E and carotene potentially prevent a shorten of cosmonaut biological age induced by solar cosmic rays and galactic cosmic rays and stress factors of long-term cosmic voyages. Radiomodulators are low and non-toxic and have not side effects in recommended doses. Their radioprotective effect is directly induced by adaption reaction on cellular and organismic levels through gene expression modulation and in that way the increase of non-specific body tolerance. The implementation of radiomodulator action is possible through hormesis mechanism.

scholarly journals Dusk-to-nighttime enhancement of mid-latitude <i>Nm</i>F2 in local summer: inter-hemispheric asymmetry and solar activity dependence

2015 ◽  
Vol 33 (6) ◽  
pp. 711-718 ◽  
Author(s):  
Y. Chen ◽  
L. Liu ◽  
H. Le ◽  
W. Wan ◽  
H. Zhang
Keyword(s):  
Solar Activity ◽  
Southern Hemisphere ◽  
Northern Hemisphere ◽  
Peak Height ◽  
Activity Level ◽  
High Solar Activity ◽  
Activity Levels ◽  
Solar Activity Level ◽  
Latitudinal Dependence ◽  
The Difference

Abstract. In this paper ionosonde observations in the East Asia–Australia sector were collected to investigate dusk-to-nighttime enhancement of mid-latitude summer NmF2 (maximum electron density of the F2 layer) within the framework of NmF2 diurnal variation. NmF2 were normalized to two solar activity levels to investigate the dependence of the dusk-to-nighttime enhancement on solar activity. The dusk-to-nighttime enhancement of NmF2 is more evident at Northern Hemisphere stations than at Southern Hemisphere stations, with a remarkable latitudinal dependence. The dusk-to-nighttime enhancement shows both increasing and declining trends with solar activity increasing, which is somewhat different from previous conclusions. The difference in the dusk-to-nighttime enhancement between Southern Hemisphere and Northern Hemisphere stations is possibly related to the offset of the geomagnetic axis from the geographic axis. hmF2 (peak height of the F2 layer) diurnal variations show that daytime hmF2 begins to increase much earlier at low solar activity level than at high solar activity level at northern Akita and Wakkanai stations where the dusk-to-nighttime enhancement is more prominent at low solar activity level than at high solar activity level. That implies neutral wind phase is possibly also important for nighttime enhancement.

scholarly journals Monthly median f0F2 and M(3000)F2 ionospheric model over Europe

1996 ◽  
Vol 39 (4) ◽  
Author(s):  
A. V. Mikhailov ◽  
V. V. Mikhailov ◽  
M. G. Skoblin
Keyword(s):  
Solar Activity ◽  
Prediction Accuracy ◽  
Spatial Interpolation ◽  
Activity Level ◽  
Ionospheric Model ◽  
Local Models ◽  
Solar Activity Level ◽  
Model Derivation ◽  
Set Of Points

Monthly median f0F2 and M(3000)F2 ionospheric model, MQMF2, based on the multiquadric (MQ) method of spatial interpolation and a new ionospheric index MF2 describes the monthly median f0F2 and M(3000)F2 over Europe for any UT moment, month and level of solar activity. The multiquadric method allows a surface to be drawn strictly over a given set of points unlike many other currently used ionosphere mapping methods. A non-linear dependence of f0F2 and M(3000)F2 on solar activity level (expressed by MF2 index) is used to establish local models for each ionosonde station. Observations on 28 ionosondes for f0F2 and 19 for M(3000)F2 over 10-30 years were used for model derivation. The MQMF provides better accuracy than the CCIR model in retrospective mode over Europe. Long-term f0F2 prediction with the help of MF2 index for the rising part of solar cycle 22 is shown to provide better prediction accuracy than the CCIR model based on sunspot number R12. MQMF2 is implemented as a code for PC AT-386/387 or compatible, providing tables, plots and maps.

scholarly journals 82 The impact of feeding treats containing cannabidiol (CBD) on the daily activity level of dogs

2020 ◽  
Vol 98 (Supplement_4) ◽  
pp. 60-61
Author(s):  
Elizabeth M Morris ◽  
Susanna E Kitts-Morgan ◽  
Dawn M Spangler ◽  
Kyle R McLeod ◽  
David L Harmon
Keyword(s):  
Daily Activity ◽  
Block Design ◽  
Companion Animals ◽  
Total Activity ◽  
Time Of Day ◽  
Activity Level ◽  
Activity Levels ◽  
Quiet Time ◽  
Activity Duration ◽  
The Impact

Abstract Growing public interest in and use of Cannabidiol (CBD) in companion animals has amplified the need to elucidate potential impacts. The purpose of this investigation was to determine the impact of CBD on daily activity of adult dogs. Twenty-four dogs (18.0 ± 3.4 kg) were utilized in a randomized complete block design with treatments consisting of control, 2 mg CBD/kg BW/d, and 4 mg CBD/kg BW/d split between two treats administered after twice-daily exercise (7:00-9:00 and 17:00-19:00). Four hours each day (10:00-12:00, AM and 13:30-15:30, PM), were designated as time when no persons entered the kennels, with 2 h designated as Quiet Time and the other 2 h as Music Time, where calming music played over speakers. Quiet and Music sessions were randomly allotted to daily AM or PM times. Activity monitors were fitted to dogs’ collars for continuous collection of activity parameters. Data were collected over a 2-wk baseline period to block dogs by activity level (high or low) before randomly assigning dogs within each block to treatments. After 1 wk of treatment adaptation, activity parameters were collected for 2 wk. Data were tested for normality using the UNIVARIATE procedure in SAS before examining differences using the MIXED procedure in SAS, including effects of treatment, day, session (Quiet or Music), time of day (AM or PM), and accompanying interactions. CBD did not alter total activity points (P = 0.9971) or activity duration (P = 0.8776). CBD tended (P = 0.0692) to reduce scratching compared to control. Irrespective of treatment, dogs were more active in PM than AM (P &lt; 0.0001). Regardless of session, dogs receiving 4 mg/kg/d tended (P = 0.0914) to be less active in the PM than control. CBD did not affect activity duration during exercise periods (P = 0.1425), but dogs receiving CBD ran more than control (P = 0.0339). These results indicate that when supplemented up to 4 mg/kg/d, CBD does not negatively impact daily activity levels of dogs.

scholarly journals Topside Ionosphere and Plasmasphere Modelling Using GNSS Radio Occultation and POD Data

2021 ◽  
Vol 13 (8) ◽  
pp. 1559
Author(s):  
Fabricio S. Prol ◽  
M. Mainul Hoque
Keyword(s):  
Solar Activity ◽  
Electron Density ◽  
Radio Occultation ◽  
Geomagnetic Latitude ◽  
Low Earth Orbit ◽  
Activity Level ◽  
Topside Ionosphere ◽  
Electron Content ◽  
Total Electron ◽  
Solar Activity Level

A 3D-model approach has been developed to describe the electron density of the topside ionosphere and plasmasphere based on Global Navigation Satellite System (GNSS) measurements onboard low Earth orbit satellites. Electron density profiles derived from ionospheric Radio Occultation (RO) data are extrapolated to the upper ionosphere and plasmasphere based on a linear Vary-Chap function and Total Electron Content (TEC) measurements. A final update is then obtained by applying tomographic algorithms to the slant TEC measurements. Since the background specification is created with RO data, the proposed approach does not require using any external ionospheric/plasmaspheric model to adapt to the most recent data distributions. We assessed the model accuracy in 2013 and 2018 using independent TEC data, in situ electron density measurements, and ionosondes. A systematic better specification was obtained in comparison to NeQuick, with improvements around 15% in terms of electron density at 800 km, 26% at the top-most region (above 10,000 km) and 26% to 55% in terms of TEC, depending on the solar activity level. Our investigation shows that the developed model follows a known variation of electron density with respect to geographic/geomagnetic latitude, altitude, solar activity level, season, and local time, revealing the approach as a practical and useful tool for describing topside ionosphere and plasmasphere using satellite-based GNSS data.

scholarly journals The Solar Twin Planet Search

2018 ◽  
Vol 619 ◽  
pp. A73 ◽  
Author(s):  
Diego Lorenzo-Oliveira ◽  
Fabrício C. Freitas ◽  
Jorge Meléndez ◽  
Megan Bedell ◽  
Iván Ramírez ◽  
...  
Keyword(s):  
Solar Activity ◽  
Activity Index ◽  
Open Clusters ◽  
Activity Level ◽  
Age Dating ◽  
Physical Parameters ◽  
Activity Levels ◽  
Sharp Drop ◽  
Activity Diagram ◽  
Activity Indices

Context. It is well known that the magnetic activity of solar-type stars decreases with age, but it is widely debated in the literature whether there is a smooth decline or if there is an early sharp drop until 1–2 Gyr that is followed by a relatively inactive constant phase. Aims. We revisited the activity-age relation using time-series observations of a large sample of solar twins whose precise isochronal ages and other important physical parameters have been determined. Methods. We measured the Ca II H and K activity indices using ≈9000 HARPS spectra of 82 solar twins. In addition, the average solar activity was calculated through asteroids and Moon reflection spectra using the same instrumentation. Thus, we transformed our activity indices into the S Mount Wilson scale (SMW), recalibrated the Mount Wilson absolute flux and photospheric correction equations as a function of Teff, and then computed an improved bolometric flux normalized activity index log R′HK (Teff) for the entire sample. Results. New relations between activity and the age of solar twins were derived by assessing the chromospheric age-dating limits using log R′HK (Teff). We measured an average solar activity of SMW = 0.1712 ± 0.0017 during solar magnetic cycles 23–24 covered by HARPS observations, and we also inferred an average of SMW = 0.1694 ± 0.0025 for cycles 10–24, anchored on a sunspot number correlation of S index versus. We also found a simple relation between the average and the dispersion of the activity levels of solar twins. This enabled us to predict the stellar variability effects on the age-activity diagram, and consequently, to estimate the chromospheric age uncertainties that are due to the same phenomena. The age-activity relation is still statistically significant up to ages around 6–7 Gyr, in agreement with previous works using open clusters and field stars with precise ages. Conclusions. Our research confirms that Ca II H & K lines remain a useful chromospheric evolution tracer until stars reach ages of at least 6–7 Gyr. We found evidence that for the most homogenous set of old stars, the chromospheric activity indices seem to continue to decrease after the solar age toward the end of the main sequence. Our results indicate that a significant part of the scatter observed in the age-activity relation of solar twins can be attributed to stellar cycle modulations effects. The Sun seems to have a normal activity level and variability for its age.

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