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Six children enrolled in a 'Kindergarten for Children with Special Needs' were the subject of a 3-month study of behavioral techniques applied to children's problem behavior through the training of parents. The children were rated as hyperactive and immature with various emotional, social, and physical problems. The study worked with the children in their natural environment (homes) and attempted to bring about change in their behavior through parental involvement. The improvement shown by the children suggested the advantage and need of early intervention in families of deviant children. (Author)

Rules were established, improved behavior was rewarded, and undesirable behavior was ignored to change disruptive classroom behavior of 25 slow learning 10-year-olds and 13 controls in a classroom setting. Experimental teachers were instructed in application of behavior modification principles. Burk's Behaviour Rating Scale (included) was used to pinpoint target behavior of Ss, and parents were surveyed to obtain information on behavior of slow learners during the experimental period. Four rules established with student participation included putting up hands to talk, staying at desks to work quietly, refraining from interrupting the teacher, and refraining from interrupting the class. Reinforcement was in the form of free time during the last period of the school day. Data showed a significant decline in the recorded means of unacceptable behaviors for both groups during the experimental period, but the control group mean was significantly lower according to both pretest and posttest data. (Author/MC)

Eighteen children (12- to 15-years-old) with learning disabilities and behavioral problems were assessed to determine the effect of desk calculators on student achievement, attitude, and behavior. The Ss, whose IQs ranged from 68 to 116, used four calculators in a mathematics class to check answers of mathematics problems for 6 months. Comparison of pretest and posttest data showed significant increases in student interest and positive attitudes towards mathematics, and reduction in disruptive behavior. (Author/MC)

A simplified structural characterization of the human skull-brain system is formulated. The model is represented by a linear elastic shell containing a linear elastic core incorporating experimentally determined properties. The model dynamic response for axisymmetric translational impact loading is sought by obtaining the shell-core static, free vibration, and time function solution. Structural validation of the human head model is demonstrated by comparing the model static stiffness coefficient, fundamental eigenfrequency, radial dynamic displacement, brain pressure, and shear response with corresponding experimental results.

The synthesis and characterization of a series of new phosphinic acids and the zinc polymers prepared from them are reported. These compositions are characterized by the presence of short polyphenylene and poly(phenylene oxide) chains as side groups. Some of the zinc derivatives were found to be tractable polymers with good thermal stability.

This paper describes a tilted plate interferometer suitable for studies in natural convection. The basic element consists of a pair of highly reflecting plates; these plates are separated by about 15 cm. Collimated light from a He–Ne laser is normally incident on the first plate; Fizeau fringes appear at the second plate. The plates are highly reflecting, resulting in sharp fringes. Despite the complicated nature of fringe formation, due to multiple reflection, fringe displacement is simply proportional to the change in index of refraction of the medium between the plates if terms of order (Δμ/gm∞)2 are neglected. Thus the form of the fringe shift vs temperature relationship is the same as for the Mach‐Zehnder interferometer. An experimental program of calibration has been conducted, and the fringe shift vs temperature relationship is confirmed.

The investigation of α - and β -aminoketones derived from thiophene isosteres of 1-indanone and 1-tetralone is described. Preliminary pharmacological data are provided.

Depolymerization of amorphous polyacetaldehyde has been studied by measurements of weight loss versus time for thin films of the polymer in vacuum. Temperatures ranged from 40 to 80°C. The samples were prepared by freezing or melting the monomer in contact with treated glass surfaces. Light scattering, osmometry, and intrinsic viscosity measurements were used to characterize the polymers. Depolymerization rates were between second and third order with respect to the unvolatilized fraction, and the activation energy was 26.3 kcal. Much of the evidence points toward a slow unzipping reaction at the chain ends, but the analysis seems to be complicated by structural variations among the samples.

An experimental investigation of the effects of heating and cooling the tool or workpiece when cutting SAE 1040 steel reveals that cooling the tool and either heating or cooling the workpiece reduces the cutting energy. Changes in cutting energy are attributed to changes in tool-chip friction and to changes in mechanical properties of the workpiece material. Caution in the prescription of hot machining is urged.

An exact solution is obtained for non-linear, flexural, asymmetric waves in a spinning membrane or a thin disk. This solution, in the form of harmonic waves, corresponds to a membrane spinning with no nodal circles and two nodal diameters. The results of the classical linear theory are deduced from this solution as wave amplitude becomes small. Examination of the flexural wave velocity-amplitude relation indicates the possibility of stationary waves for a fixed ratio of wave amplitude and membrane angular velocity. For stationary waves, the radial displacements of particles in the membrane are inward everywhere except at the axis where this vanishes.

An uncoupled representation of the equations governing free, axisymmetric, large-amplitude, transverse vibrations of spinning membrane disks is derived. Exact expressions for transverse displacement, stress resultants, and frequency of non-linear oscillations are obtained for a special case of disk vibration. The technique for uncoupling the governing field equations is applied to the study of axisymmetric vibrations of non-spinning membrane disks.

Mathematical models of the human left ventricle are presented to determine the physiological response-oriented mechanical parameters of the LV, which have diagnostic significance. These parameters are (i) the rheological parameters of the left ventricular muscle, namely the instantaneous values of stiffness of series elasticity, parallel elasticity, and the stress-strain rate relationship for the contractile unit that characterizes the deviatric stress-strain response of a left ventricular muscle element, (ii) the effective modulus of the LV, and (iii) the state of stress in the LV. The rheological parameters are obtained from a continuum model of the LV whose stress state equilibrates the chamber pressure and whose strain state equals the instantaneous strains in the actual LV, obtained from instantaneous changes in the geometry of the LV (as noted from cineangiocardiography); the constitutive equations for the model incorporate the known existing rheological models for the isolated cardiac muscle. The effective moduli of the LV are obtained by correlating the fundamental frequency of vibration of a spherical model of the LV with the corresponding frequencies of the second component of the first heart sound and the third heart sound; thus the values of representative moduli (and hence indices of the left ventricular stiffnesses) at systole and diastole are obtained. The stress state in the LV is obtained by utilizing single plane cineangiocardiographic information of the irregular geometry of the LV in anteroposterior projection. Plane stress finite element analysis of this planor irregular geometry of the LV is done and the resulting stresses are reduced by a factor, heuristically determined to make allowance for the actual 3-dimensional geometry of the LV; the stresses obtained thus bring out effects of irregular boundary of varying (and at times high) curvature.

Several methods of computing critical depth in trapezoidal channels are described; various equations are expressed in terms of suitable nondimensional parameters in order to make them universal in application.