Color-coded measures of myocardial velocity throughout the cardiac cycle by tissue Doppler imaging to quantify regional left ventricular function

TDI is a new echocardiographic technique that calculates and displays color-coded myocardial velocity on-line. To determine the feasibility of endocardial velocity throughout the cardiac cycle as a means to quantify regional function, 20 normal subjects aged 30 +/- 5 years and 12 patients with heart disease aged 62 +/- 17 years were studied with a prototype TDI system. TDI M-mode images were acquired by using a multicolored velocity map (display range, -30 to 30 mm/sec; temporal resolution, 90 Hz). Color-coded velocity data were then converted to numeric values off-line at 50 msec intervals. Posterior wall velocities throughout the cardiac cycle by TDI were closely correlated with velocity calculations from the first derivative of routine digitized M-mode tracings (group mean r = 0.88 +/- 0.03, SEE = 7.0 +/- 1.1 mm/sec). Anteroseptal TDI color-coded systolic velocity occurred 164 +/- 84 msec from the onset of the electrocardiographic QRS compared with 203 +/- 33 msec in the posterior wall (P < 0.05) in normal subjects, consistent with normal electrical activation. Significant differences in systolic and diastolic posterior wall TDI velocity data were observed in patients with hypokinetic or akinetic segments assessed by independent routine study when compared with normal controls. Calculated systolic and early diastolic posterior wall TDI indexes correlated significantly with percentage of wall thickening. Of abnormal anteroseptal segments, TDI systolic time velocity integrals were significantly different than normal and correlated with percentage of wall thickening. TDI has potential to quantitatively assess regional left ventricular function.     

Immunocytochemical studies on Schistosoma mansoni. II. Soluble cercarial antigens in cercarial and schistosomules

The localization of soluble, cercarial antigen preparation (CAP) in cercariae and schistosomules of Schistosoma mansoni was performed at the light and electron microscope levels using the unlabeled antibody method. Reaction produce was observed associated with the contents of the pre- and postacetabular glands and with the filamentous coat of mature cercariae. No reaction product was observed associated with the glycoacalyx of schistosomules. However, several schistosomules did retain remnants of their filamentous coats and reaction product was observed associated with those remains. CAP components were also observed in the area surrounding the intrasporocyst cercariae.     

On the pop-in mode of fracture

Experimental observations concerning the pop-in mode of fracture obtained during an investigation of the fracture toughness of glassy plastics are related. Comments on the mechanics of the pop-in mode are presented.     

A comparison of estimators of output multipliers from incomplete input-output data

This paper presents derivations and empirical tests of three formulas for estimating output multipliers with only limited input-output type data. The first formula assumes only knowledge of the proportion of the value of output of the firm or industry in question which is respent within the region, as well as an estimate of the average of this value over all industries. The second formula assumes this value as well as the relative values of the I-O row totals. The third equation assumes data equivalent to a column in the I-O matrix is known for the specific firm or industry in question. The data requirements for all three formulas are modest but are more for (2) than for (1) and are more for (3) than for (2). All three formulas are shown to be quite reliable but the third gives especially close estimates of the actual multipliers for the several models tested. It is concluded that fairly rough estimates of the average interindustry proportion can be safely used but it is important to obtain the firm or industry expenditure (direct effects) data as accurately as possible.     

Solid-phase immune electron microscopy (SPIEM) for rapid viral diagnosis

Immune electron microscopy (IEM) is one of the fastest and most sensitive methods for the detection and diagnosis of viruses. This technique is based on formation of immune complexes of the virus with its corresponding antibody. In IEM optimal precipitation depends on a correct ratio, and there is a prozone effect. These problems can be overcome by using the solid-phase immune electron microscopic (SPIEM) technique. In this technique the antibody is attached to a particle which is used for 'fishing' the virus to be examined out of the suspension. After low speed centrifugation the preparation is treated either for observation in the transmission electron microscope or in the scanning electron microscope. In 'positive' samples the virus is seen attached to the surface of the particle. We report here results with S. aureus as the solid phase for the detection of Sindbis virus. The anti-Sindbis gamma globulins are attached to the bacteria by means of protein A present on their surface.     

On the least time control problem with interior output constraints

A variational problem arising in the study of least time controls is formulated in terms of norms of functionals on suitable Banach spaces. The existence of a solution is demonstrated by an appeal to the Hahn-Banach theorem, and the form of solution is developed from the equality conditions for Hölder's inequality. The systems being controlled are linear, but not necessarily time invariant, and the results may accordingly find application in the control of batch processing systems.