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Tabletop versus microcomputer-assisted speech management: stabilization phase.

Few controlled data are available on the efficacy of microcomputers for speech management with children. The focus of this second report in a study series using microcomputers with speech-delayed children (Shriberg, Kwiatkowski, & Snyder, 1986) is on the response stabilization stage of speech management. Two repeated-measures designs were conducted with two samples of preschool children (n = 18) to compare tabletop management with comparable computer-assisted activities. Findings indicate that response stabilization tasks in the two intervention modes were equally effective, efficient, and engaging. Additional analyses suggest that the two modes engage the children in different ways, however, and that children may have individual needs for mode-specific features.

Age Factors

A microcomputer-based real-time system for measurement and analysis of umbilical flow velocity waveforms obtained by Doppler ultrasound.

A microcomputer-based system for real-time acquisition and analysis of umbilical arterial blood flow velocity waveforms is described. The spatial peak umbilical flow velocity is transduced by a pulsed Doppler flowmeter and digitized by the microcomputer. The computer allows for coherent averaging of flow velocity over several heart cycles in order to minimize noise that is uncorrelated with the fetal heart beats. In addition, it can compute flow velocity indices that do not require knowledge of the angle of beam incidence or umbilical arterial cross-sectional area. The averaged waveform as well as the computed indices may be displayed in real time. Further, these results may be saved on disk along with other relevant clinical information to be subsequently merged into a relational data base covering all patients monitored. Not only does the system facilitate accurate measurement of umbilical flow velocity waveforms, but the relational data base may also be used to evaluate the clinical significance of these measurements in a patient population.

Blood Flow Velocity

A microcomputer-based system for the management of vascular surgical references.

As the number and diversity of contributions to the medical literature continue to grow at an astronomic rate, vascular surgeons are feeling increasingly frustrated in their efforts to remain current with the latest developments in their specialty. The introduction of powerful, inexpensive microcomputers and "user-friendly" programs for data base management has made it possible to organize large amounts of information for subsequent review. Using such a microcomputer-based system, we developed a practical approach to the storage and retrieval of vascular surgical references, which permits virtually unlimited numbers of articles to be catalogued and quickly retrieved with multiple search parameters. This system has been operational in our Division of Vascular Surgery for nearly a year and currently contains more than 3000 journal articles that are readily available for resident teaching, patient care, and research.

Information Systems

Microcomputer-aided measurement of puff parameters during smoking of low- and medium-tar cigarettes.

A portable microcomputer-assisted flow transducer was developed for analysing puff parameters during smoking of low- and medium-tar cigarettes. Smoke flow was determined by measuring pressure difference between two sites within an orifice flowmeter. According to the Bernoulli equation, the pressure difference is proportional to the square of flow. For calibration of the method, various sizes of air volumes were puffed through the flowmeter by a piston syringe. The calibration curve, which consisted of the flow as a function of the square root of pressure difference, was linear (r = 0.98). The automatic microcomputer analysis consists of the following variables: mean flow and mean volume of inhaled smoke gas, puff duration, time interval between two puffs, number of puffs and total volume inhaled. Eight volunteers smoked 10 low- and 10 medium-tar cigarettes during the cross-over experiments. The investigation indicated that the total inhalation volume of smokers in the case of low-tar cigarettes is twice as large as in the case of medium-tar cigarettes.

Humans

Computerized spirometry using a portable microcomputer.

The reliable conduct of pulmonary function studies, while in the field, is increasingly important as various standards mandate this activity. Versatile, portable and accurate equipment is required. A lightweight and computerized portable spirometer system is discussed, PSPIRO, which uses a standard volumetric spirometer and a briefcase-sized microcomputer. The system, compact enough to be easily moveable by one person, performs tests for FVC, FEV(1), FEV(3), the percentage of predicted pulmonary function for each, and the ratio of FEV(1)/FVC. Back extrapolation is used to establish the start of each forced expiratory maneuver, reproducibility checks are performed, and accuracy is within acceptable epidemiologic standards. A small, portable analog to digital interface (PLAD) was developed for performing A/D conversions through the RS-232C port of the portable microcomputer.

Humans

Collection and analysis of complex ELISA data using a microcomputer.

A system for automatic Enzyme-Linked Immunosorbent Assay (ELISA) data collection and processing is described. Hardware for the system consists of a Dynatech microplate reader and Apple II series microcomputer. Software developed by the authors allows automatic configuration of the reader and direct data input from the microplate reader to the microcomputer. After optical density data is input through the interface, it can be printed out as either optical density values, or as scaled values (from 0 to 9) in a color-coded matrix. Data can be stored and later recalled in either format, allowing several sets of data to be merged into one large, color-coded chart. Results from several different microplates can be combined and sorted in a single printout to expedite interpretation of data.

Computers

Optimised microcomputer-guided quantitative microradiography on dental mineralised tissue slices.

It is well realised that the contact microradiographic method is the most direct method that gives position-dependent information on the mineral content of calcified tissue and its loss. We developed a microcomputer-guided microradiographic system which features fast operation by the experimenter with a low appearance of errors. Tooth tissue slices of 75 micron thickness are cut with a sawing machine. Images (Cu K alpha radiation) of the tooth slice and an aluminium step wedge (exposure 10-15 s) are made on film (Kodak SO-253). The images of step wedge and tooth slice are scanned in a densitometer (1 micron X 30 microns slit), which is fitted with an XY table (0.5 micron steps). A microcomputer (Apple IIe) is programmed to control the XY table and to record the optical film transmission. Scans of the images are plotted on the computer screen. The calibration step optical film transmission values are determined by the operator by adjusting a computer-generated bar onto the individual steps shown on the screen. The dose-density relation of the film is approximated by the program by a fourth-degree polynomial using the step-wedge data. The resulting curve is used to convert the tooth-slice data into a mineral volume percentage. To enable the calculation of total mineral loss (in kg m-2) (loss integrated over depth), the operator adds the assumed diagram for sound enamel onto the display. This is done by adjusting computer-generated bars to the scan of the tooth slice shown on the screen. The resolving power in the image made by the microradiographic system is 3 microns X 30 microns. On the basis of the analysis of random errors and a comparison with chemical analysis of tooth slices we claim that the error in mineral volume percentage amounts to 4% of its value. Starting with a microradiographic image of a tooth slice 5 min are required to obtain a microradiographic curve on paper and to obtain a value for mineral loss.

Humans

Nonlinear regression on a microcomputer: which program?

Eleven published programs for performing nonlinear regression using a microcomputer have been reviewed. They have been assessed according to many criteria, especially: application, program language, algorithm used, method for calculating partial differentials, facility for weighting, desirable input and output features, robustness during execution, memory requirements, accessability, ease of implementation and evaluation and testing. No one program contains all the desirable characteristics discussed, but guidance is given as to which might be the most suitable for a particular purpose or for a given microcomputer system.

Algorithms

Optimal alignments of biological sequences on a microcomputer.

An algorithm and a program have been developed which enable optimal alignments of biological sequences on an 8-bit microcomputer. The compiled program can process sequences up to 1000 residues on a Commodore 64. Since this program was written originally in the BASIC language, it may readily be adapted to other microcomputers with small changes.

Algorithms

A microcomputer program for the identification of tRNA genes.

A microcomputer program which locates tRNA genes within long DNA sequences is described. The search is performed either by identifying tRNA-like secondary structures or by locating eukaryotic RNA polymerase III promoter consensus sequences. The program is also useful in finding inverted repeats allowing the formation of stem-loop secondary structures in tRNA. The program has been developed in BASIC and 6502 Assembler and runs on the Apple II plus and IIe microcomputers. The execution is quite fast; all the operations are carried out in 1-90 s, depending on the required task and on the sequence length.

Base Sequence

ANTHEPROT: a package for protein sequence analysis using a microcomputer.

A simple microcomputer package is described to make the theoretical analysis of protein sequences. Several methods designed to compare two sequences, to model proteolytic reactions and to predict the secondary structure, the hydrophobic/hydrophilic regions and the potential antigenic sites of proteins have been included in an Apple II microcomputer software. The package comprises 21 programs as well as the secondary structure database of Kabsch and Sander (1983).

Algorithms

Portable microcomputer software for nucleotide sequence analysis.

The most common types of nucleotide sequence data analyses and handling can be done more conveniently and inexpensively on microcomputers than on large time-sharing systems. We present a package of computer programs for the analysis of DNA and RNA sequence data which overcomes many of the limitations imposed by microcomputers, while offering most of the features of programs commonly available on large computers, including sequence numbering and translation, restriction site and homology searches with dot-matrix plots, nucleotide distribution analysis, and graphic display of data. Most of the programs were written in Standard Pascal (on an Apple II computer) to facilitate portability to other micro-, mini-, and and mainframe computers.

Base Sequence

Applications of microcomputer spreadsheet packages as adjuncts to multiple logistic regression analysis.

This paper illustrates how a microcomputer spreadsheet package can be used by epidemiologists to facilitate the computation of multiple logistic regression (MLR) probabilities, as well as odds ratios and associated confidence intervals, given the coefficients of the MLR model. By formatting a spreadsheet, data entry is greatly simplified, and computations are accomplished without any arithmetic manipulations on the part of the user. This approach makes it feasible for clerical support staff to assist in the computation of seemingly complex expressions. The increasing availability of microcomputers in clinical and research settings suggests that numerous analytic applications are amenable to this approach, thereby decreasing reliance on mainframe computers and desk-top calculators.

Computers

Forensic diagnosis coding and retrieval by microcomputer.

A system is described for coding of anatomic--including forensic--pathologic diagnoses from necropsy cases using a microcomputer. The SNOMED software from the College of American Pathologists is utilized. RAM-disk software is employed to enhance the speed of operation of the system. The microcomputer can be operated by clerical staff versed in medical terminology. Speed of entry and retrieval, with minimal manual interaction, is an important aspect of operation. Equipment and storage costs are minimal.

Forensic Medicine

Measuring the problem-solving ability of students and residents by microcomputer.

Potential uses for microcomputers in medical education include evaluation of students and residents. A computer program developed at the University of Pennsylvania School of Medicine and the Children's Hospital of Philadelphia presents simulated patient cases and then scores participants' clinical problem-solving in the cases by comparing their performances with those of five faculty members. In the study reported here, the authors investigated the validity and reliability of this evaluation system. Total scores were significantly different among faculty members, residents, and third-year students on only the most difficult of the three cases included in the study. Performance was not related to the user's general analytic ability or to locus of control. This result suggested there is not a "type" of person who is better at medical problem-solving on a microcomputer. A prophecy formula was used to determine that nine cases would be needed to achieve an adequate level of reliability in measuring the ability of a student or a resident. Implications of selecting a battery of cases for the system are discussed.

Clinical Competence

A model of a microcomputer database system to assist medical schools in recruiting and retaining students.

A model for a microcomputer database to aid a school's efforts to recruit and retain students is presented. The model is based upon a working system developed by the author at the University of Colorado Health Sciences Center. The article discusses data needs for adequate records of the recruitment and retention efforts, especially those concerning minority students, and how these records can be used to administer and evaluate programs. The model provides a framework for microcomputer data files, record fields, relationships, and system development and maintenance considerations.

Colorado

A microcomputer algorithm for solving compartmental models involving radionuclide transformations.

An algorithm for solving first-order non-recycling compartment models is described. Given the initial amounts of a radioactive material in each compartment and the fundamental transfer rate constants between each compartment, the algorithm gives both the amount of material remaining at any time t and the integrated number of transformations that would occur up to time t. The method is analytical, and consequently, is ideally suited for implementation on a microcomputer. For a typical microcomputer with 64 kilobytes of random access memory, a model containing up to 100 compartments, with any number of interconnecting translocation routes, can be solved in a few seconds; providing that no recycling occurs. An example computer program, written in 30 lines of Microsoft BASIC, is included in an appendix to demonstrate the use of the algorithm. A detailed description is included to show how the algorithm is modified to satisfy the requirements commonly encountered in compartment modelling, for example, continuous intake, partitioning of activity, and transformations from radioactive progeny. Although the algorithm does not solve models involving recycling, it is often possible to represent such cases by a non-recycling model which is mathematically equivalent.

Computers

A microcomputer algorithm for solving first-order compartmental models involving recycling.

A general algorithm for solving first-order compartmental models including recycling systems has been developed and its implementation on a microcomputer is described. Matrix algebra is used to obtain for any compartmental model an analytical solution, which is expressed as the exponential of a matrix of rate constants. A special technique is used in the algorithm to enable this exponential to be evaluated with a rapidly converging series. Truncation errors incurred in this process are estimated automatically. Thus, in an extreme case, where these errors may be significant, the appropriate action can be taken. Given a particular model, the user enters the model parameters into a rate matrix according to a simple rule. The algorithm then uses this matrix to solve the model, and thus no specialized mathematical knowledge is needed. The algorithm is given in a short BASIC program (60 lines) listed in an appendix. No additional software is required. By running this program on a standard microcomputer, the user can solve models of any complexity: those up to 15 compartments in seconds and those up to 30 compartments within a minute. The algorithm is thus ideally suited to solve kinetic models describing the transport of radionuclides in the environment or the translocation of elements in biological systems such as the metabolic models recommended by the International Commission on Radiological Protection (ICRP). Given the initial amount of material in each compartment at time t = 0, together with its radioactive decay constant, the algorithm gives both the amount in each compartment at any future time t and the number of disintegrations that will have occurred in each compartment up to time t. The computer program, shown in an appendix, could easily be used to calculate disintegrations over any time interval of interest, or to predict the quantities or fractions of an intake expected to be present in any in vivo or excretion compartments of interest. Thus, the algorithm can be useful in both the design and conduct of bioassay and internal dose assessment procedures.

Algorithms