Modeling the Forward-Scatter Cross Section of 3-Dimensional Objects by Means of the Shadow Contour Theorem: An Assessment

2018 ◽  
Author(s):  
Davide Comite ◽  
Marta Tecla Falconi ◽  
Alessandro Galli ◽  
Frank Silvio Marzano ◽  
Pierfrancesco Lombardo
Keyword(s):  
Cross Section ◽  
Scatter Cross Section ◽  
Forward Scatter ◽  
3 Dimensional

A model for the topology of the chloroplast thylakoid membrane

1999 ◽  
Vol 26 (7) ◽  
pp. 687 ◽  
Author(s):  
Per-Ola Arvidsson ◽  
Cecilia Sundby
Keyword(s):  
Cross Section ◽  
Electron Micrographs ◽  
Thylakoid Membrane ◽  
Dimensional Structure ◽  
Cross Sectional ◽  
3 Dimensional ◽  
Topological Organization

A model for the topological organization of the chloroplast thylakoid membrane is presented. A series of illustrations is provided, which outline a suggested 3-dimensional structure in cross-section and in full shape, which accounts both for the folding of one continuous membrane into multiple grana stacks as seen in cross-sectional electron micrographs and for the rapid reversible unfolding (destacking) of the grana stacks into lamellar sheets.

Transthoracic 3-dimensional echocardiography in the assessment of subaortic stenosis due to a restrictive ventricular septal defect in double inlet left ventricle with discordant ventriculoarterial connections

1999 ◽  
Vol 9 (6) ◽  
pp. 549-555 ◽  
Author(s):  
Michael Vogel ◽  
S. Yen Ho ◽  
Robert H. Anderson ◽  
Andrew N. Redingtont
Keyword(s):  
Aortic Valve ◽  
Left Ventricle ◽  
Ventricular Septal Defect ◽  
Cross Section ◽  
Septal Defect ◽  
Subaortic Stenosis ◽  
3 Dimensional ◽  
En Face ◽  
Dimensional Echocardiography ◽  
Double Inlet Left Ventricle

AbstractTo evaluate the accuracy and clinical utility of three-dimensional echocardiography in the assessment of the size and shape of the ventricular septal defect in double inlet left ventricle.MethodsWe validated the technique in an autopsy study, and then performed a clinical investigation. Six autopsied hearts were immersed in a waterbath and examined with 3-dimensional echocardiography. We identified the cross-section within the dataset which optimally displayed the ventricular septal defect “en face”, and compared its smallest and largest diameters, as well as its area. The ventricular septal defect was then filled with a silicone sealant and a section prepared for direct measurement. In patients, we measured the diameters and area of the ventricular septal defect in endsystole nad computed the aortic valvar area in endsystole from the cross-section showing the aortic valve “en face”. Ten patients with double inlet left ventricle, aged between 2 and 15 years, were studied using rotational or parallel scanning. All patients had undergone banding of the pulmonary trunk at a mean age of 7 (3–36) days, usually at the time of repair of the coarctation. Two patients had undergone surgical enlargement of the ventricular septal defect prior to echocardiographic examination.ResultsThe correlation between the areas of the ventricular septal defect in the specimens measured directly and by 3-dimensional echocardiography was r=0.98, with limits of agreement between −0.1– 0.08 cm2. In the patients, the area of the defect was measured as 3.9±2 cm2, whereas the aortic valvar area was 2.6±0.9 cm2. The ratio between the areas was 1.5 (0.5–2.3). Three patients with areas of the ventricular septal defect smaller than those of the aortic valve had resting Doppler gradients between double inlet left ventricle and the aorta of 16, 20 and 30 mm Hgs, respectively.Conclusions3-dimensional echocardiography provides accurate assessment of the area of the ventricular septal defect in double inlet left ventricle, and is helpful in identifying patients with subaortic stenosis caused by restrictive defects.

Imaging of the angular-dependent coherent-scatter cross section with analyzer crystal: a Monte Carlo simulation

2011 ◽  
Vol 36 (15) ◽  
pp. 2785
Author(s):  
Sergei Gasilov ◽  
Paul Claude Diemoz ◽  
Emmanuel Brun ◽  
Paola Coan
Keyword(s):  
Monte Carlo Simulation ◽  
Monte Carlo ◽  
Cross Section ◽  
Scatter Cross Section ◽  
Coherent Scatter ◽  
Analyzer Crystal

The Vascular System of the Wheat Spikelet

1985 ◽  
Vol 12 (5) ◽  
pp. 487 ◽  
Author(s):  
T.P O'Brien ◽  
M.E Sammut ◽  
J.W Lee ◽  
M.G Smart
Keyword(s):  
Cross Section ◽  
Vascular Tissue ◽  
Vascular System ◽  
Histological Study ◽  
Cell Types ◽  
Dimensional Model ◽  
3 Dimensional ◽  
Attachment Region ◽  
Important Pathway ◽  
Different Cell Types

The attachment region of a mid-spike spikelet was sectioned serially. These sections were used to construct an accurate 3-dimensional model of the course of the vascular system that supplies the organs of the a and b florets, and the rachilla of the c and d florets. All organs are interconnected by vascular tissue, but certain parts of the system are phloem-only. In particular, the supply to the groove bundle of the pericarp, widely held to be the most important pathway to the grain, is made via an annulus of phloem to which lemma, palea and lodicules have phloem-only connections. The vascular system is sufficiently different from the pattern encountered in vegetative nodes to warrant treatment sui generis. The relationships between different cell types need greater histological study, especially in the complex composite bundles. This analysis shows that bundle shape in cross-section and the arrangement of xylem and phloem vary sharply over very short distances (100 ~ m ) .T he distribution of xylem and phloem transfer cells agrees with the proposal that significant solute relocation takes place in the regions where the vascular supplies to different organs meet. The area in the ovary neck that encompasses the fusion zone of the supplies to lemma, palea and pericarp emerges as a zone in need of detailed study, both in spikelet positions within a cultivar of known, but different, grain performance, and as a region to analyse for inter-cultivar comparisons.

Tomographic imaging of the angular-dependent coherent-scatter cross section

1997 ◽  
Vol 24 (1) ◽  
pp. 3-10 ◽  
Author(s):  
M. S. Westmore ◽  
A. Fenster ◽  
I. A. Cunningham
Keyword(s):  
Cross Section ◽  
Scatter Cross Section ◽  
Tomographic Imaging ◽  
Coherent Scatter

A New Method to Determine Crack Shape and Size in Solder Joints

1995 ◽  
Vol 117 (4) ◽  
pp. 266-269
Author(s):  
T. Reinikainen ◽  
F. W. Wulff ◽  
W. Kolbe ◽  
T. Ahrens
Keyword(s):  
Cross Section ◽  
Fatigue Cracks ◽  
Temperature Cycling ◽  
3 Dimensional ◽  
Black And White ◽  
Ceramic Capacitor ◽  
Processing Program ◽  
Scanned Images ◽  
Dimensional Picture ◽  
Shape And Size

In this paper, a method based on image analysis is introduced to produce a 3-dimensional picture of a solder joint. This 3-D image gives a detailed view of the solder contour and the fatigue cracks inside the solder. The practical example is a surface mount 1206 ceramic capacitor which has been soldered on a FR4 board with Sn62Pb36Bi2 solder. The assembly has been through severe temperature cycling. The 3-D image is created by first making several (≈15) micrographs of the cross-section of the joint until the whole joint has been examined. The photopositives are then scanned with a black and white scanner. To each of the scanned micrographs the contours of component metallisation, copper pad and solder are marked manually using an image processing program. Another program has been developed to extract the marked contours from the scanned images and to place them on a CAD-file with the correct distance between them. With CAD the 3-D image of the contours can be viewed from different view points and also the fatigue crack inside the joint can be seen and measured.

scholarly journals Spectral characteristics and scatter cross-section of low latitude mesospheric echoes measured by the Indian MST radar at Gadanki

2012 ◽  
Vol 30 (6) ◽  
pp. 983-990 ◽  
Author(s):  
E. Belova ◽  
S. Kirkwood ◽  
T. Narayana Rao ◽  
S. Satheesh Kumar ◽  
T. Sergienko
Keyword(s):  
Energy Dissipation ◽  
Cross Section ◽  
Scatter Cross Section ◽  
Spectral Characteristics ◽  
Turbulent Energy ◽  
Scattering Mechanism ◽  
Low Latitude ◽  
Special Experiment ◽  
Mst Radar ◽  
First Time

Abstract. In November 2008 and in March and April 2009 the Indian MST radar (53 MHz) at Gadanki was operated during the daytime in a special experiment, with 600 m altitude resolution, for understanding the characteristics of low-latitude mesospheric echoes (LLME). The data of three days when the echoes were strongest have been analysed in terms of spectral widths and radar volume reflectivities. Spectral widths of LLME show some decrease with altitude, with median values of 4–6 m s−1 at 69–72 km and of 2–4 m s−1 at 73–78 km. This corresponds to 20–200 mW kg−1 turbulent energy dissipation rates. It has been shown that stronger echoes have broader spectra consistent with a turbulent scattering mechanism. For the first time, the volume reflectivities for the strong LLME for Gadanki have also been calculated. They are in the range of 10−17–10−15 m−1, so LLME at Gadanki are somewhat stronger than those reported so far from Jicamarca, Peru (Lehmacher et al., 2009).

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