Hand dominance and scoliosis in Duchenne muscular dystrophy

Twenty-three patients with Duchenne muscular dystrophy and scoliosis were studied. In all but one patient the major convexity was to the side of the dominant hand. The unsupported growing spine is easily unbalanced by asymmetrical forces imposed on it. From our observations we believe major use of a single upper extremity will result in scoliosis with the major convexity toward the side of the dominant hand. Management should include counterbalancing the postural abnormality imposed by hand dominance as well as unloading the spine frequently during the patient's waking hours.     

Control of divergence in Kalman filters

Techniques for control of divergence of the Kalman filter are considered. The application in practice of three decision-directed methods for divergence prevention is investigated. A critical study of the measures of filter quality and the control actions which these methods employ is presented and a new method is suggested for control of divergence in the standard filter.     

Echocardiographic oscillating flap in aortic root dissecting aneurysm

A patient had a history, physical findings, and chest x-ray film suggesting type I aortic dissection. This diagnosis could not be confirmed angiographically. Echocardiographic studies predicted both the presence of dissection and the anatomic findings at surgery. A regularly oscillating echo corresponding to the intimal flap was found in the false lumen. This is suggested as a new echocardiographic finding in dissecting aneurysm.     

Effects of Measurement Devices on Conducted Interference Levels

Measurements of power line conducted interference voltages are commonly made throughout the 150 kHz to 30 MHz frequency range on military, industrial, and consumer equipment using line impedance stabilization networks (LISN) and, more recently, current probe techniques. This paper presents some brief background information concerning power line conducted interference measurements and the results of a study to assess the effects of LISN and current probe measurement devices on the level of measured conducted interference. A model is defined which facilitates prediction of the effects. The model concept allows the procedures described in this paper to be extended to equipment of other impedance definitions. A comparison of the calculated and empirical differences is made and suggests an analytical approach in sizing the effects upon the conducted interference levels.     

Transformations of linear-graph theory in multivariable-system problems

A correspondence is established between the multimachine power system, the multivariable control system and the classical least-squares problem incorporating a priori information. A transformation diagram is developed to illustrate the relationships between the system variables, which are similar to those associated with a linear graph or electrical network.     

Histomorphological and histochemical studies on systemic and pulmonary arteries of goat with advancing age. I. Occurrence of physiological intimal cushions in different arteries of goat

Thirty three goats, ranging from twenty days to over five years, were included in present investigation which revealed calcification of the different layers of seventeen different collateral arterial branches as well as various aortic segments. The initial appearance of calcium deposition and its progression with advancing age in goats was noted. The calcium deposition in the elastic elements, smooth muscle cells of tunica media, and constituents of tunica adventitia was observed and discussed in light of the available literature in domestic animals.