scholarly journals On the Distribution of Angular Velocity in the Sun

1976 ◽  
Vol 71 ◽  
pp. 415-415
Author(s):  
Jaakko Tuominen

The angular velocity distribution as a function of heliographic latitude is directly observed at the solar surface. Also the dependence of the angular velocity on the distance from the solar centre can be studied observationally for the outermost layers of the Sun. But within the Sun the study of angular velocity depends very much on assumptions. One possibility to study the problem is given by the fact that in a bipolar magnetic group the leader is compact while the follower is dispersed over a large area. In Leighton's theory, following Babcock, this phenomenon is explained, in principle, in the following way: Slide 1. When a magnetic rope, as a result of magnetic buoyancy, rises to the surface, it is twisted by differential rotation. Dashed lines in the figure represent isotachial surfaces. When the rope has risen to the surface, the two ends are twisted in opposite directions. The surface differential rotation continues to twist one of the now free ends of the rope, while it untwists the other free end. Both twisting and untwisting are, in fact, very slow. They are fastest at the latitude of 35°, where the magnetic rope is rotated once in 26 days. We understand that the distribution of angular velocity within the Sun is involved in this picture. The twisting in the interior can be written equal to the untwisting of the follower spot produced by the surface differential rotation. Of course there are many solutions. Slide 2 gives two of them. The lines represent calculated isotachial surfaces and the numbers give the observed angular velocities in radians per day. In the left-hand side distribution the velocity decreases inwards, while in the right-hand side distribution it increases inwards. The right-hand side distribution is also consistent with the conclusion derived from observations that the tilt of sunspot axes from the vertical is relatively small, and with the observation that at the equatorial plane, near the surface, the rotational velocity does not vary with depth.

1991 ◽  
Vol 130 ◽  
pp. 297-308
Author(s):  
Steven S. Vogt ◽  
Artie P. Hatzes

AbstractWe present a sequence of three Doppler images of the spotted RS CVn star UX Arietis obtained over a 5-month interval from August 1986 through January 1987. The spot distribution was quite complex and consisted of a large stable polar spot, a spot near the equator, and several other spots at intermediate positive and negative latitudes. The time intervals between successive images were small enough that we were able to reliably track the evolution of the spot distribution, measuring accurate longitudes, latitudes, and areas of the major spots, as well as their drift rates in longitude and latitude. The longitudinal drifts of spot features at equatorial, intermediate, and high latitudes yielded an accurate measurement of differential rotation. We find that the spotted primary of UX Arietis is indeed rotating differentially and in the sense opposite to that of the Sun, i.e. the poles rotate faster than the equator. The equator is synchronized to the orbital angular velocity, and the angular velocity increases towards either pole. The angular velocity distribution can be expressed as Ω(°/day) = −55.91 + 1.09(±0.09) sin2∅, where ∅ is the latitude. The amount of differential rotation, parameterized as the ratio of the difference between the equatorial and polar angular velocities to the equatorial angular velocity, is then α = −0.020(±0.002), as compared to a value of α = +0.2 for the Sun.


1970 ◽  
Vol 4 ◽  
pp. 321-328
Author(s):  
W.C. Livingston

AbstractThe problem of determining the spectroscopic rotation of the sun is not one of instrumental sensitivity, which can be about 10 m/sec, but rather of abstracting the rotational component from the hierarchy of long-lived surface currents. Required are continued daily observations over long periods of time and this task is not presently feasible at most observatories. Past observations have indicated a height gradient of rotational angular velocities. We have determined the photosphere and chromosphere angular velocity gradient from observations across the disk of C 5380 Å(h≃ -250 km), CN 3882 Â (h ≃ 0 km), Ca+K3(h≃+ 5000 km), together with other Fraunhofer lines of intermediate origin while K-line spectra of prominences are used to sense the chromosphere-corona interface.


1946 ◽  
Vol 11 (1) ◽  
pp. 2-2

In the article “Infant Speech Sounds and Intelligence” by Orvis C. Irwin and Han Piao Chen, in the December 1945 issue of the Journal, the paragraph which begins at the bottom of the left hand column on page 295 should have been placed immediately below the first paragraph at the top of the right hand column on page 296. To the authors we express our sincere apologies.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Velarie Ansu ◽  
Stephanie Dickinson ◽  
Alyce Fly

Abstract Objectives To determine which digit and hand have the highest and lowest skin carotenoid scores, to compare inter-and-intra-hand variability of digits, and to determine if results are consistent with another subject. Methods Two subjects’ first(F1), second(F2), third(F3) and fifth(F5) digits on both hands were measured for skin carotenoids with a Veggie Meter, for 3 times on each of 18 days over a 37-day period. Data were subjected to ANOVA in a factorial treatment design to determine main effects for hand (2 levels), digits (4), and days (18) along with interactions. Differences between digits were determined by Tukey's post hoc test. Results There were significant hand x digit, hand x day, digit x day, and hand x digit x day interactions and significant simple main effects for hand, digit, and day (all P < 0.001). Mean square errors were 143.67 and 195.62 for subject A and B, respectively, which were smaller than mean squares for all main effects and interactions. The mean scores ± SD for F1, F2, F3, and F5 digits for the right vs left hands for subject A were F1:357.13 ± 45.97 vs 363.74 ± 46.94, F2:403.17 ± 44.77 vs. 353.20 ± 44.13, F3:406.76 ± 43.10 vs. 357.11 ± 45.13, and F5:374.95 ± 53.00 vs. 377.90 ± 47.38. For subject B, the mean scores ± SD for digits for the right vs left hands were F1:294.72 ± 61.63 vs 280.71 ± 52.48, F2:285.85 ± 66.92 vs 252.67 ± 67.56, F3:268.56 ± 57.03 vs 283.22 ± 45.87, and F5:288.18 ± 34.46 vs 307.54 ± 40.04. The digits on the right hand of both subjects had higher carotenoid scores than those on the left hands, even though subjects had different dominant hands. Subject A had higher skin carotenoid scores on the F3 and F2 digits for the right hand and F5 on the left hand. Subject B had higher skin carotenoid scores on F5 (right) and F1 (left) digits. Conclusions The variability due to hand, digit, and day were all greater than that of the 3 replicates within the digit-day for both volunteers. This indicates that data were not completely random across the readings when remeasuring the same finger. Different fingers displayed higher carotenoid scores for each volunteer. There is a need to conduct a larger study with more subjects and a range of skin tones to determine whether the reliability of measurements among digits of both hands is similar across the population. Funding Sources Indiana University.


Südosteuropa ◽  
2019 ◽  
Vol 67 (2) ◽  
pp. 175-195
Author(s):  
Petru Negură

Abstract The Centre for the Homeless in Chișinău embodies on a small scale the recent evolution of state policies towards the homeless in Moldova (a post-Soviet state). This institution applies the binary approach of the state, namely the ‘left hand’ and the ‘right hand’, towards marginalised people. On the one hand, the institution provides accommodation, food, and primary social, legal assistance and medical care. On the other hand, the Shelter personnel impose a series of disciplinary constraints over the users. The Shelter also operates a differentiation of the users according to two categories: the ‘recoverable’ and those deemed ‘irrecoverable’ (persons with severe disabilities, people with addictions). The personnel representing the ‘left hand’ (or ‘soft-line’) regularly negotiate with the employees representing the ‘right hand’ (‘hard-line’) of the institution to promote a milder and a more humanistic approach towards the users. This article relies on multi-method research including descriptive statistical analysis with biographical records of 810 subjects, a thematic analysis of in-depth interviews with homeless people (N = 65), people at risk of homelessness (N = 5), professionals (N = 20) and one ethnography of the Shelter.


Cell Reports ◽  
2016 ◽  
Vol 17 (11) ◽  
pp. 2809-2810
Author(s):  
Jody C. Culham
Keyword(s):  

1987 ◽  
Vol 101 (2) ◽  
pp. 89-94
Author(s):  
J. Bruyn

AbstractOf the nine interpretations proposed for Rembraradt's history Painting of 1626 now at Leiden, none is really convincing. Il seems attractive to think of palamedes Condemned by Agamemncm as the subject because of its political significance in the year after the publication of Voredel's tragecty Palamedcs or Innocence Murdered, which denounced the execution of the Remonstrant leader Johan van Oldenbarnevelt in 1619. γet the scene depicted does not fit any episode frorn the Palamedes story. It appears rather to represent three young men appearing before a crowned figure who makes a pronouncement, probably one of magnanimity or clemency. It is conceivable that the subject was taken from Q. Curtius Rufus's Historiae Alexandri Magni Macedonis, ofwhich several editions, including translations into the vernacular, were published in Holland in the first decades of the 17th century. The episode in question was known to the young Rubens, but does not seem to have been illustrated by any other artist. At the beginning of the seventh book it is described how Alexander summoned before. him in the presence of the army two oj three brothers, who had been close friends of Philotas, a former, friend of his who had been executed for plotting against his life. The youngest brother, Poleinon, had panicked and fled but was caught and brought back at the very moment when Alexander had accused the brothers and the eldest, Amyntas, after having been released from his bonds and given a spear which he held in his left hand, had embarked on his szzccess ful defence. The appearance of Polemon infuriated the soldiers, but when he took the blame on himself and prrifessed his brothers' innocence, they were moved to tears. So too was Alexander who, prompted by their cries, absolved the brothers. This anecdote does at least explain some of the features of Rembrandt's scene. The young man standing on the right with his right hand raised as if swearing an oath would be the eloquent Amyntas with a spear in his left hand. Hidden behind him kneels the second brother, Simias, while Polemon, 'a young man just come to maturity and in the first bloom of his youth', has fallen on one knee in the foreground, underlining his emotional words with his right hand bressed to his heart. Alexander raises his sceptre in token of his absolution and some men in the background wave and shout from a socle they have climbed. Interpreted in this way, the scene coralains not a topical political allegory but, as would seem usual with history paintings, a message of a more general nature: the magnanimity of Alexander as an 'exemblum virtutis'.


2011 ◽  
Vol 2011 ◽  
pp. 1-13 ◽  
Author(s):  
Iva Franjić ◽  
Sadia Khalid ◽  
Josip Pečarić

The lower bounds of the functional defined as the difference of the right-hand and the left-hand side of the Jensen inequality are studied. Refinements of some previously known results are given by applying results from the theory of majorization. Furthermore, some interesting special cases are considered.


2007 ◽  
Vol 22 (1) ◽  
pp. 24-25
Author(s):  
Naotaka Sakai

Among 703 professional pianists with medical problems in their hands seen by the author between 1981 and 2000, there were 27 patients who had interosseous muscle pain (23 women, 4 men; mean age, 30 yrs). The main symptom was dorsal hand pain during piano performance, especially when striking the keys with each finger rounded, mainly in the scale technique. Tenderness was noted in the deep part of the dorsal hand in the interosseous muscles, but not along or around the finger extensors. Patients sometimes complained of muscle weakness on abduction of the index, ring, and/or little fingers when performing octaves or chords on the piano keyboard. Resisted abduction and adduction testing of the fingers reproduced the pain which they experienced during or after performance. Pain occurred in the right hand in 10, left hand in 5, and bilaterally in 12. The pain was localized in the 4th and 5th interossei in 15 patients, in the 3rd and 4th in 14 patients; in the 2nd and 3rd in 11 patients; and in the 1st and 2nd in 1 patient.


2008 ◽  
Vol 24 (3) ◽  
pp. 280-287 ◽  
Author(s):  
Yong “Tai” Wang ◽  
Konstantinos Dino Vrongistinos ◽  
Dali Xu

The purposes of this study were to examine the consistency of wheelchair athletes’ upper-limb kinematics in consecutive propulsive cycles and to investigate the relationship between the maximum angular velocities of the upper arm and forearm and the consistency of the upper-limb kinematical pattern. Eleven elite international wheelchair racers propelled their own chairs on a roller while performing maximum speeds during wheelchair propulsion. A Qualisys motion analysis system was used to film the wheelchair propulsive cycles. Six reflective markers placed on the right shoulder, elbow, wrist joints, metacarpal, wheel axis, and wheel were automatically digitized. The deviations in cycle time, upper-arm and forearm angles, and angular velocities among these propulsive cycles were analyzed. The results demonstrated that in the consecutive cycles of wheelchair propulsion the increased maximum angular velocity may lead to increased variability in the upper-limb angular kinematics. It is speculated that this increased variability may be important for the distribution of load on different upper-extremity muscles to avoid the fatigue during wheelchair racing.


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