scholarly journals WALKING THE NARROW RIDGE: When Performing Neutrality Isn’t an Option in the Vocation of the Christian Professor

Author(s):  
Jessica Clements
Keyword(s):  
2009 ◽  
Vol 1202 ◽  
Author(s):  
Wen Feng ◽  
Vladimir Kuryatkov ◽  
Dana Rosenbladt ◽  
Nenad Stojanovic ◽  
Mahesh Pandikunta ◽  
...  

AbstractWe report selective area epitaxy of InGaN/GaN micron-scale stripes and rings on patterned (0001) AlN/sapphire. The objective is to elevate indium incorporation for achieving blue and green emission on semi-polar crystal facets. In each case, GaN structures were first produced, and the InGaN quantum wells (QWs) were subsequently grown. The pyramidal InGaN/GaN stripe along the <11-20> direction has uniform CL emission at 500 nm on the smooth {1-101} sidewall and at 550 nm on the narrow ridge. In InGaN/GaN triangular rings, the structures reveal smooth inner and outer sidewall facets falling into a single type of {1-101} planes. All these {1-101} sidewall facets demonstrate similar CL spectra which appear to be the superposition of two peaks at positions 500 nm and 460 nm. Spatially matched striations are observed in the CL intensity images and surface morphologies of the {1-101} sidewall facets. InGaN/GaN hexagonal rings are comprised of {11-22} and {21-33} facets on inner sidewalls, and {1-101} facets on outer sidewalls. Distinct CL spectra with peak wavelengths as long as 500 nm are observed for these diverse sidewall facets of the hexagonal rings.


1999 ◽  
Vol 354 (1385) ◽  
pp. 869-875 ◽  
Author(s):  
E. Otten

The balance of standing humans is usually explained by the inverted pendulum model. The subject invokes a horizontal ground–reaction force in this model and controls it by changing the location of the centre of pressure under the foot or feet. In experiments I showed that humans are able to stand on a ridge of only a few millimetres wide on one foot for a few minutes. In the present paper I investigate whether the inverted pendulum model is able to explain this achievement. I found that the centre of mass of the subjects sways beyond the surface of support, rendering the inverted pendulum model inadequate. Using inverse simulations of the dynamics of the human body, I found that hip–joint moments of the stance leg are used to vary the horizontal component of the ground–reaction force. This force brings the centre of mass back over the surface of support. The subjects generate moments of force at the hip–joint of the swing leg, at the shoulder–joints and at the neck. These moments work in conjunction with a hip strategy of the stance leg to limit the angular acceleration of the head–arm–trunk complex. The synchrony of the variation in moments suggests that subjects use a motor programme rather than long latency reflexes.


2017 ◽  
Vol 53 (1) ◽  
pp. 40-42
Author(s):  
M. Wang ◽  
T. Hosoda ◽  
L. Shterengas ◽  
G. Kipshidze ◽  
D.J. Hwang ◽  
...  

1987 ◽  
Vol 115 ◽  
pp. 352-354 ◽  
Author(s):  
R. Kawabe ◽  
N. Kaifu ◽  
S. S. Hayashi ◽  
T. Hasegawa

We have made HCO+ (J = 1-0), HCN (J = 1-0) and CS (J = 2-1) observations of a bipolar flow source GL490 (Lada and Harvey 1981; Snell et al. 1984) using the Nobeyama 45-m telescope with 20″ resolution. A HCO+ spectrum obtained toward a central infrared source (Harvey et al. 1979) has prominent line wings extending up to 15-25 km s−1 from the line center (Figure 1). Figure 2 shows a map of HCO+ high velocity emission more than 8 km s−1 off the line center. The emission has “head-tail”-structures in both the blue- and the red-shifted sides; a “head” with stronger emission and a “tail” with weaker narrow ridge emission extending to the opposite side of the “head” through the center. The “head” emission has the same bipolar structure as the CO flow. Intermediate velocity emission at 38 km s−1 from the line center shows (1) a narrow ridge elongated in the NE-SW direction, at the blue-shifted side, and (2) a pair of shell-like structures symmetrically placed SW and NE of the center of the high velocity emission, at the red-shifted side (Figure 3).


1883 ◽  
Vol 35 (224-226) ◽  
pp. 155-161 ◽  

The specimens to which the following note refers were dredged in the Faroë Channel in the autumn of last year, during the cruise of H. M. S. “Triton,” and were sent to me for examination by Mr. John Murray, F. R. S. E., under whose direction the scientific observations of the expedition were carried out. It is now a well-known fact that the region lying between the north coast of Scotland and the Faroë Islands possesses certain features of unusual interest owing to the existence, side by side, of two sharply defined areas, of which the bottom temperature differs to the extent of 16° or 17° Fahr. The depth of the two areas is very similar, ranging from 450 to 640 fathom s, and they are separated by a narrow ridge having an average depth of about 250 fathoms. The physical aspects of this phenomenon have been the subject of much discussion, and the biological conditions attendant thereupon are of almost equal importance; indeed, so far as the Rhizopoda are concerned, there are few areas of the same extent that have so well repaid the labour of investigation. On the 44 "Lightning” Expedition of 1868, supei-intended by Dr. Carpenter and Sir Wyville Thomson, the cold area furnished amongst other interesting organisms, the large Lituoline Foraminifer Reophax sabulosa , a form which has since been obtained near the same point on the cruise of the "Knight Errant," but has never been met with elsewhere. The warm area yielded at the same time Astrorhiza arenaria , a large sandy species previously unknown to British naturalists. On the "Porcupine” Expedition of 1869, another modification of the latter genus, Astrorhiza crassatina was obtained in the cold area; and near the boundary line an entirely new arenaceous type was dredged, to which the generic named Botellina has been assigned by Dr. Carpenter. From the fact that all the specimens of the form appeared more or less broken, it has been inferred that the tests were adherent when living; but the fragments were abundant and consisted of stout tubes, many of them upwards of an inch in length, the interior being subdivided by a labyrinth of irregular sandy partitions. More recently, in 1880, on the cruise of the “K night Errant,” the rare genus Storthosphœra was found in the warm region and in the cold area specimens of Cornusjpira which measured more than an inch in diameter, rivalling in size the finest of the tropical Orbitolites, and therefore amongst the largest known Porcellanoug Foraminifera.


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