**Moire fringe topography
setup**

(1970-1979)

**C46: 3-D-Optical
Imaging and Image Processing (Biomedical Applications)**

*Work done at: **UNIVERSITY OF KARACHI, University Road, Karachi 75270,
Pakistan**
*

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This paper covered biomedical applications of 3-D optical imaging techniques - moiré fringe topography and rasterstereography - in the studies of posture and gait of children. Techniques were developed to project simultaneously moiré and raster grids and analyze the height and the curvature information, separately, using selective optical filtering for applications in gait analysis. 3-D static and dynamic models of the human spinal column were developed capable to display movements during the four phases of gait cycle, linking each phase with the subsequent one through edge-based algorithm. Edge-based algorithm, combined with moiré contours, allowed study of motion in the sagittal plane. 3-D structure of macromolecules significant in biology may be studied by making their metallic replica and applying these techniques. Preliminary work was done on the flagella of salmonella typhus at the Albert Einstein College of Medicine (New York). Full Text PDF

**C45: Planetary-Orbit Modeling
Based on Astrodynamical Coördinates**

*Work done at: **UNIVERSITY OF KARACHI, University Road, Karachi 75270,
Pakistan**
*

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The planetary orbits are, in general, the elliptical orbits with sun at one of the foci. The problem is, traditionally, formulated using the plane-polar coördinates, not a natural choice for such type of trajectories. The two-body problem has 12 degrees-of-freedom (3 translational, 3 rotational for each of the two bodies), which were reduced to 6 by neglecting structures. Further, setting up the problem in the center-of-mass (CM) frame-of-reference, separated the lagrangian into 2 terms, the first one representing motion of CM and the second motion about CM. Realizing that CM was either at rest or moving with a uniform velocity in the absence of external forces, the first term was constant and, hence, played no role in the lagrangian equations, which, only, involved derivatives. Hence, the problem was reduced to 3 degrees-of-freedom. In the absence of external torques, angular momentum (a vector quantity having both magnitude and direction) was conserved. A fixed direction of angular momentum in space forced two-body orbits to lie in a plane, making the problem 2 dimensional. The orbital equation of motion was formulated using the elliptic-astrodynamical-coördinate mesh, evolved from the elliptic-cylindrical-coördinate mesh. This further reduced the degrees-of-freedom and the problem became a true one-parameter problem. Kepler’s equation was shown to be a particular solution of this equation. This formulation generated 3 (instead of the customary 2) constants of motion.

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Science is an intellectual activity that extends the process of consciousness to the most abstract and the most fundamental levels. The existing five paradigms have changed the fundamental concepts physicists have about the relationship of space, time and matter. In order to interpret the data and develop satisfactory theories to explain them, a sixth paradigm of physics needs to be introduced. This paper suggests the mathematical struc-ture of this new paradigm.

**C43: Physics of Screening Procedures to Detect Trunk
Deformities**

*Work done at: **UNIVERSITY OF
KARACHI, University Road, Karachi 75270, Pakistan**
*

sentation)

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An Integrated-Trunk-Deformities-Screening System was described, which would involve multiple-level screening

of school-going children. The checks located at the top level were designed to be highly sensitive and could be performed in a semi-private setting. The checks located at the bottom level were chosen to be highly specific. These involve moiré fringe topography of back in the anatomical position, footprint molds in the anatomical position and shoe soles as well as footprint analysis during walking on sand. These were compared with the standard forward-bending test. The goal was to minimize X-ray exposure to children while identifying at risk children for the orthopedic referral.

**C42: 3-D-Dynamic Modeling of the Human Spinal Column**

*Work done at: **UNIVERSITY OF
KARACHI, University Road, Karachi 75270, Pakistan**
*

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This model, a generalization of 3-D static model developed earlier, included movement of the human spinal

column during a gait cycle. The human spinal column in three dimensions was generated from moiré topographs

of back in the anatomical position as well as during the first, the second, the third and the fourth phases of gait cycle. Spinal column in the anatomical position was subsequently linked to position during the first phase of gait cycle through the edge-based algorithm. Similarly, position in the second phase was linked to the first phase through the edge-based algorithm and so on. Apart from the medical sciences where this model could be utilized in the study of the human gait one may apply this model in space medicine where physiology of the human spine could be studied in subdued gravity,

**C41: Computer-Based Analysis of Human Gait using Moiré Fringe Topography**

*Work done at: **THE SIR SYED UNIVERSITY OF ENGINEERING AND TECHNOLOGY,
University Road, Karachi 75300, Pakistan
*Yosufzai
MAK,

and Parallel Processing

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In this communication moiré technique was employed to analyze the human gait in four phases of the steps for healthy-school-going children of ages 3-8 years. The patterns generated indicated the spinal deformities and their relative difference. It, also, imparted clinically-relevant information, which offered diagnostic clues to the orthopedic surgeons, without facing difficulty to interpret the results.

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Working of the brain presents one of the most challenging problems of neurosciences. It is an extremely complex structure containing something of the order of 10

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Acoustic properties of heart were modeled by applying the concepts of wave theory. Heart was considered as a system of standing waves. The nature and the origin of various frequencies were investigated. Experimental suggestions were, briefly, mentioned. Full Text PDF

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Wave-theory concepts were applied to develop a model of acoustic properties of the human heart. Theoretical predictions were compared with data obtained from normal children. Heart sounds were recorded and subsequently converted into electrical signals. These signals were Fourier analyzed to determine the amplitudes and the frequencies of various harmonics.

Siddiqui KA,

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Global-electrocortical activity of the human brain was modeled as a system of damped-coupled-harmonic oscillators. The equations were written in a covariant form using tensorial notations. Generalized coupling dependent on both the electrical potentials and their rates of change was introduced in the covariant model. Perturbation effects and physiological implications were discussed.

Akram M,

couver, Canada, 1991 (poster presentation) — corresponding author

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Skeletal examination of school athlete is a significant part of the general physical examination because it may uncover many underlying problems, which could effect the performance in athletics and sports. For example, in pubertal children an undetected curvature of spinal column may lead to a deformity effecting cosmetic appearance. The early detection of scoliosis, kyphosis and lordosis, therefore, is a major concern of school health services. In addition, the basic goal of an athletic program should be to develop better body image of an athlete. Studies of posture and gait of athletes are, therefore, of interest to researchers in sports medicine. Moiré fringe topography is a stereophotogrammetric technique, which provides a three-dimensional map of the object (or subject) under study. This paper described the applications of moiré techniques in the study of posture and gait of children as well as detection and documentation of curvatures of spinal column.

Siddiqui KA,

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Brain is a complex system and the brain theory is developing into a central focus among many disciplines. The function of brain has long been prominent among topics of fundamental interest to biologists and physicists, alike. After an introduction of brain and the physics involved, a spacetime representation of global electrocortical activity was given. The concept of analyzing EEG signals by mathematical modeling was, also, touched upon. Full Text PDF

C34: Reproducibility of Moiré Topographs

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This paper examined the issues regarding the reproducibility of moiré topographs and outlined the need for an objective criterion of reproducibility. A criterion was proposed to obtain reproducible moiré pictures. An experiment was designed to test this criterion. Full Text PDF

C33: A Comparison of Back Moiré Topographs of Children in Sitting and Standing Positions

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This was the report on a study being conducted to compare the moiré topographs of children in the sitting and the standing positions to determine if there was a significant difference in the two positions. Full Text PDF

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Moiré topography is being increasingly used in the study of scoliosis. For a child suffering from scoliosis moiré topographs on the two halves of the back are not similar. Since scoliosis is a lateral curvature of the spinal column it should, also, affect moiré topograph of the side. The effect is expected to be more prominent when the child is examined in the forward-bending position. This paper reported an ongoing study, which included side moiré topographs of 100 normal, healthy 8-10-year old boys studying in a local school in Hyderabad, Sindh.

Full Text PDF

Richard E. Lindesth, M. D. Professor of Orthopedic Surgery Head, Section of Pediatric Orthopedics Indiana University School of Medicine Indianapolis, United StatesFebruary 24, 1982 |

Abstracts of Conference Papers (1970-1979) (1980-1989) (2010-2013) (2014-)

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