Design and Marker-Based Validation of a Biplane Fluoroscopy System for Studying the Foot and Ankle

2012 ◽  
Author(s):  
Joseph M. Iaquinto ◽  
Richard Tsai ◽  
Michael J. Fassbind ◽  
David R. Haynor ◽  
Bruce J. Sangeorzan ◽  
...  
Keyword(s):  
Precise Measurement ◽  
Three Dimensional ◽  
The Body ◽  
Initial Evaluation ◽  
Foot And Ankle ◽  
Research Groups ◽  
The Past ◽  
Model Based ◽  
Biplane Fluoroscopy ◽  
Model Based Analysis

The ability to accurately measure three dimensional (3D) bone kinematics is key to understanding the motion of the joints of the body, and how such motion is altered by injury, disease, and treatment. Precise measurement of such kinematics is technically challenging. Biplane fluoroscopy is ideally suited to measure bone motion. Such systems have been developed in the past for both radiographic stereo-photogrammetric analysis (RSA) [1] and the more challenging model-based analysis [2]. Research groups have studied the knee [3,4], shoulder [5] and ankle [6] motion with similar techniques. The work presented here is an initial evaluation of the performance of our system, i.e., a validation that this in-house system can detect magnitudes of motion on-par with other existing systems.

scholarly journals An Automated Three-Dimensional Bone Pose Tracking Method Using Clinical Interleaved Biplane Fluoroscopy Systems: Application to the Knee

2020 ◽  
Vol 10 (23) ◽  
pp. 8426
Author(s):  
Cheng-Chung Lin ◽  
Tung-Wu Lu ◽  
Jia-Da Li ◽  
Mei-Ying Kuo ◽  
Chien-Chun Kuo ◽  
...  
Keyword(s):  
Imaging System ◽  
Three Dimensional ◽  
Pose Tracking ◽  
Model Based ◽  
X Ray Imaging ◽  
Custom Made ◽  
Optical Motion ◽  
Optical Motion Capture ◽  
Tibiofemoral Kinematics ◽  
Biplane Fluoroscopy

Model-based tracking of the movement of the tibiofemoral joint via a biplane X-ray imaging system has been commonly used to reproduce its accurate, three-dimensional kinematics. To accommodate the approaches to existing clinical asynchronous biplane fluoroscopy systems and achieve comparable accuracy, this study proposed an automated model-based interleaved biplane fluoroscopy image tracking scheme (MIBFT) by incorporating information of adjacent image frames. The MIBFT was evaluated with a cadaveric study conducted on a knee specimen. The MIBFT reproduced skeletal poses and tibiofemoral kinematics that were in good agreement with the standard reference kinematics provided by an optical motion capture system, in which the root-mean-squared (Rms) errors of the skeletal pose parameters ranged from 0.11 to 0.35 mm in translation and 0.18 to 0.49° in rotation. The influences of rotation speed on the pose errors were below 0.23 mm and 0.26°. The MIBFT-determined bias, precision, and Rms error were comparable to those of the reported model-based tracking techniques using custom-made synchronous biplane fluoroscopy. The results suggested that the further use of the clinical imaging system is feasible for the noninvasive and precise examination of dynamic joint functions and kinematics in clinical practice and biomechanical research.

scholarly journals THREE-DIMENSIONAL BILLIARDS WITH TIME MACHINE

1996 ◽  
Vol 05 (02) ◽  
pp. 179-192 ◽  
Author(s):  
MICHAEL B. MENSKY ◽  
IGOR D. NOVIKOV
Keyword(s):  
World Line ◽  
Identical Particle ◽  
Three Dimensional ◽  
The Body ◽  
Closed Trajectory ◽  
Time Machine ◽  
Billiard Ball ◽  
The Past ◽  
Small Ideal ◽  
Classical Point

Self-collision of a nonrelativistic classical point-like body, or particle, in the spacetime containing closed time-like curves (time-machine spacetime) is considered. A point-like body (particle) is an idealization of a small ideal elastic billiard ball. The known model of a time machine is used containing a wormhole leading to the past. If the body enters one of the mouths of the wormhole, it emerges from another mouth in an earlier time so that both the particle and its “incarnation” coexist during some time and may collide. Such self-collisions are considered in the case when the size of the body is much less than the radius of the mouth, and the latter is much less than the distance between the mouths. Three-dimensional configurations of trajectories with a self-collision are presented. Their dynamics is investigated in detail. Configurations corresponding to multiple wormhole traversals are discussed. It is shown that, for each world line describing self-collision of a particle, dynamically equivalent configurations exist in which the particle collides not with itself but with an identical particle having a closed trajectory (Jinnee of Time Machine).

scholarly journals MACPET: model-based analysis for ChIA-PET

Biostatistics ◽  
2019 ◽  
Vol 21 (3) ◽  
pp. 625-639
Author(s):  
Ioannis Vardaxis ◽  
Finn Drabløs ◽  
Morten B Rye ◽  
Bo Henry Lindqvist
Keyword(s):  
Binding Sites ◽  
Present Model ◽  
Dimensional Space ◽  
Three Dimensional ◽  
Model Based Clustering ◽  
Model Based ◽  
Motif Occurrence ◽  
Calling Algorithm ◽  
Genomic Regions ◽  
Model Based Analysis

Summary We present model-based analysis for ChIA-PET (MACPET), which analyzes paired-end read sequences provided by ChIA-PET for finding binding sites of a protein of interest. MACPET uses information from both tags of each PET and searches for binding sites in a two-dimensional space, while taking into account different noise levels in different genomic regions. MACPET shows favorable results compared with MACS in terms of motif occurrence and spatial resolution. Furthermore, significant binding sites discovered by MACPET are involved in a higher number of significant three-dimensional interactions than those discovered by MACS. MACPET is freely available on Bioconductor. ChIA-PET; MACPET; Model-based clustering; Paired-end tags; Peak-calling algorithm.

Scanning electron microscopy of freeze-fractured prescapular lymph node of caprine

1984 ◽  
Vol 42 ◽  
pp. 244-245
Author(s):  
O. Faroon ◽  
F. Al-Bagdadi ◽  
T. G. Snider ◽  
C. Titkemeyer
Keyword(s):  
Lymph Node ◽  
Lymph Nodes ◽  
Lymphatic System ◽  
Three Dimensional ◽  
Meat Products ◽  
The Body ◽  
Morphological Data ◽  
The World ◽  
Cellular Constituent ◽  
Scanning Electron

The lymphatic system is very important in the immunological activities of the body. Clinicians confirm the diagnosis of infectious diseases by palpating the involved cutaneous lymph node for changes in size, heat, and consistency. Clinical pathologists diagnose systemic diseases through biopsies of superficial lymph nodes. In many parts of the world the goat is considered as an important source of milk and meat products.The lymphatic system has been studied extensively. These studies lack precise information on the natural morphology of the lymph nodes and their vascular and cellular constituent. This is due to using improper technique for such studies. A few studies used the SEM, conducted by cutting the lymph node with a blade. The morphological data collected by this method are artificial and do not reflect the normal three dimensional surface of the examined area of the lymph node. SEM has been used to study the lymph vessels and lymph nodes of different animals. No information on the cutaneous lymph nodes of the goat has ever been collected using the scanning electron microscope.

Mitochondrial Reconstructions Based on Serial Thick Sections and HVEM

1975 ◽  
Vol 33 ◽  
pp. 286-287
Author(s):  
Jerome J. Paulin
Keyword(s):  
Imaging Techniques ◽  
Three Dimensional ◽  
Posterior Pole ◽  
Dimensional Structure ◽  
Stereo Imaging ◽  
Thin Sections ◽  
Anatomical Features ◽  
The Past ◽  
Cellular Components ◽  
Mitochondrial Reticulum

Within the past decade it has become apparent that HVEM offers the biologist a means to explore the three-dimensional structure of cells and/or organelles. Stereo-imaging of thick sections (e.g. 0.25-10 μm) not only reveals anatomical features of cellular components, but also reduces errors of interpretation associated with overlap of structures seen in thick sections. Concomitant with stereo-imaging techniques conventional serial Sectioning methods developed with thin sections have been adopted to serial thick sections (≥ 0.25 μm). Three-dimensional reconstructions of the chondriome of several species of trypanosomatid flagellates have been made from tracings of mitochondrial profiles on cellulose acetate sheets. The sheets are flooded with acetone, gluing them together, and the model sawed from the composite and redrawn.The extensive mitochondrial reticulum can be seen in consecutive thick sections of (0.25 μm thick) Crithidia fasciculata (Figs. 1-2). Profiles of the mitochondrion are distinguishable from the anterior apex of the cell (small arrow, Fig. 1) to the posterior pole (small arrow, Fig. 2).

Derrida on Pornography: Putting (It) Up for Sale

Derrida Today ◽  
2013 ◽  
Vol 6 (1) ◽  
pp. 97-114 ◽  
Author(s):  
Christopher Morris
Keyword(s):  
Cultural Studies ◽  
English Translation ◽  
The Body ◽  
The Past ◽  
French Original ◽  
Definition Of ◽  
Critical Discourses ◽  
Academic Debate

Over the past thirty years, academic debate over pornography in the discourses of feminism and cultural studies has foundered on questions of the performative and of the word's definition. In the polylogue of Droit de regards, pornography is defined as la mise en vente that is taking place in the act of exegesis in progress. (Wills's idiomatic English translation includes an ‘it’ that is absent in the French original). The definition in Droit de regards alludes to the word's etymology (writing by or about prostitutes) but leaves the referent of the ‘sale’ suspended. Pornography as la mise en vente boldly restates the necessary iterability of the sign and anticipates two of Derrida's late arguments: that there is no ‘the’ body and that performatives may be powerless. Deriving a definition of pornography from a truncated etymology exemplifies the prosthesis of origin and challenges other critical discourses to explain how pornography can be understood as anything more than ‘putting (it) up for sale’.

A Qualified Assertion Database for the History of Places

2019 ◽  
Vol 13 (1-2) ◽  
pp. 95-115
Author(s):  
Brandon Plewe
Keyword(s):  
Data Model ◽  
Temporal Change ◽  
Religious Congregations ◽  
Historical Gis ◽  
The Past ◽  
Model Based ◽  
Complex Information ◽  
Invaluable Tool ◽  
History Of ◽  
The Rich

Historical place databases can be an invaluable tool for capturing the rich meaning of past places. However, this richness presents obstacles to success: the daunting need to simultaneously represent complex information such as temporal change, uncertainty, relationships, and thorough sourcing has been an obstacle to historical GIS in the past. The Qualified Assertion Model developed in this paper can represent a variety of historical complexities using a single, simple, flexible data model based on a) documenting assertions of the past world rather than claiming to know the exact truth, and b) qualifying the scope, provenance, quality, and syntactics of those assertions. This model was successfully implemented in a production-strength historical gazetteer of religious congregations, demonstrating its effectiveness and some challenges.

Receptions of the Past: Commemoration, Racism, Desire

Somatechnics ◽  
2017 ◽  
Vol 7 (2) ◽  
pp. 288-303
Author(s):  
Michael Connors Jackman
Keyword(s):  
Critical Point ◽  
Social Relations ◽  
White Privilege ◽  
Body Politic ◽  
The Body ◽  
Race And Racism ◽  
Lesbian And Gay ◽  
The Past ◽  
History Of

This article investigates the ways in which the work of The Body Politic (TBP), the first major lesbian and gay newspaper in Canada, comes to be commemorated in queer publics and how it figures in the memories of those who were involved in producing the paper. In revisiting a critical point in the history of TBP from 1985 when controversy erupted over race and racism within the editorial collective, this discussion considers the role of memory in the reproduction of whiteness and in the rupture of standard narratives about the past. As the controversy continues to haunt contemporary queer activism in Canada, the productive work of memory must be considered an essential aspect of how, when and for what reasons the work of TBP comes to be commemorated. By revisiting the events of 1985 and by sifting through interviews with individuals who contributed to the work of TBP, this article complicates the narrative of TBP as a bluntly racist endeavour whilst questioning the white privilege and racially-charged demands that undergird its commemoration. The work of producing and preserving queer history is a vital means of challenging the intentional and strategic erasure of queer existence, but those who engage in such efforts must remain attentive to the unequal terrain of social relations within which remembering forms its objects.

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