Intraoperative Identification of the Central Sulcus: a Practical Method

1988 ◽  
pp. 22-26 ◽  
Author(s):  
T. Aiba ◽  
Yojiro Seki
Keyword(s):  
Practical Method ◽  
Central Sulcus

The role of differential phase contrast in electron microscopy

1978 ◽  
Vol 36 (1) ◽  
pp. 176-177
Author(s):  
E.M. Waddell ◽  
J.N. Chapman ◽  
R.P. Ferrier
Keyword(s):  
Phase Contrast ◽  
Practical Method ◽  
Position Vector ◽  
Differential Phase ◽  
Pure Phase ◽  
Differential Phase Contrast ◽  
The Difference ◽  
Image Position ◽  
First Moment

Dekkers and de Lang (1977) have discussed a practical method of realising differential phase contrast in a STEM. The method involves taking the difference signal from two semi-circular detectors placed symmetrically about the optic axis and subtending the same angle (2α) at the specimen as that of the cone of illumination. Such a system, or an obvious generalisation of it, namely a quadrant detector, has the characteristic of responding to the gradient of the phase of the specimen transmittance. In this paper we shall compare the performance of this type of system with that of a first moment detector (Waddell et al.1977).For a first moment detector the response function R(k) is of the form R(k) = ck where c is a constant, k is a position vector in the detector plane and the vector nature of R(k)indicates that two signals are produced. This type of system would produce an image signal given bywhere the specimen transmittance is given by a (r) exp (iϕ (r), r is a position vector in object space, ro the position of the probe, ⊛ represents a convolution integral and it has been assumed that we have a coherent probe, with a complex disturbance of the form b(r-ro) exp (iζ (r-ro)). Thus the image signal for a pure phase object imaged in a STEM using a first moment detector is b2 ⊛ ▽ø. Note that this puts no restrictions on the magnitude of the variation of the phase function, but does assume an infinite detector.

Scoring concepts maps: Can a practical method of scoring concept maps be used to assess trainee's knowledge structures?

2004 ◽  
Author(s):  
Michelle E. Harper ◽  
Raegan M. Hoeft ◽  
A. W. Evans ◽  
Florian G. Jentsch
Keyword(s):  
Concept Maps ◽  
Practical Method ◽  
Knowledge Structures

Practical Method for Transient Stability with Unbalanced Condition based on Symmetric Coordinates

2011 ◽  
Vol 131 (7) ◽  
pp. 550-556
Author(s):  
Shuhei Fujiwara ◽  
Yoshiyuki Kono ◽  
Masashi Kitayama ◽  
Tadahiro Goda
Keyword(s):  
Transient Stability ◽  
Practical Method

Total Synthesis of the Antitumor Depsipeptide FE399 and its S-Benzyl Derivative: A Macrolactamization Approach

2020 ◽  
Author(s):  
Takayuki Tonoi ◽  
Miyuki Ikeda ◽  
Teruyuki Sato ◽  
Ryo Kawahara ◽  
Takatsugu Murata ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Total Synthesis ◽  
Natural Product ◽  
Condensation Reaction ◽  
Practical Method ◽  
Equilibrium Mixture ◽  
Conformational Isomers ◽  
Single Isomer

<div>An efficient and practical method for the synthesis of (9R,14R,17R)-FE399, a novel antitumor bicyclic depsipeptide, was developed. A 2-methyl-6-nitrobenzoic anhydride (MNBA)-mediated dehydration condensation reaction was effectively employed for the formation of the 16-membered macrocyclic depsipeptide moiety of FE399. FE399 was found to exist as an inseparable equilibrium mixture of conformational isomers; the mixture was quantitatively transformed into the corresponding S-benzyl product and isolated as a single isomer. Thus, we could confirm that the molecular structure of FE399 obtained by this method is identical to that of the natural product.</div>

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