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Biomedical subjects

S E Palmer

Publications and source records attributed to S E Palmer.

At least 19 recordsLinked to original sources
PubMed1992

Common region: a new principle of perceptual grouping.

A new principle of grouping is proposed that is based on elements being located within a common region of space. Demonstrations analogous to Wertheimer's original displays show that this factor strongly influences perceived grouping and is capable of overcoming the effects of other powerful grouping factors such as proximity and similarity. Grouping by common region is further shown to depend on perceived depth relations, indicating that it is influenced by processes that occur after at least some depth perception has been achieved. Further demonstrations suggest that it is dominated by the smallest background area and that it can follow a hierarchical embedding scheme. It is argued that common region cannot be reduced to the effects of proximity, closure, or any other previously known factor and therefore constitutes a genuinely new principle of grouping.

Depth Perception↗
PubMed1992

Group treatment program for abusive husbands: long-term evaluation.

Long-term outcomes of a short-term group treatment program for abuse husbands were investigated in a controlled study. Recidivism rates, based on police reports, were found to be lower than those for a control group of untreated abusive husbands; they were also found to be lower for those men initially exhibiting greater depression. Implications for further research are discussed.

Adult↗
PubMed1992

Rapid fetal lung maturity testing: commercial versus NBD-phosphatidylcholine assay.

We compared the TDx Fetal Lung Maturity test and the fluorescence polarization method using 1-palmitoyl-2(6-[(7-nitro-2,1,3-benzoxadiazol-4- yl)amino]caproyl)phosphatidylcholine (NBD-phosphatidylcholine). Using 76 paired human amniotic fluid samples, the fluorescence polarization values of the two methods were found to have a strong nonlinear correlation (r2 = 0.946). Both assays can be completed in less than 1 hour, have excellent precision (between-day variation less than 2%), and indicate the amount of surfactant phospholipid relative to albumin. The FLM assay is calibrated with surfactant/albumin standards; therefore, the reported results (in mg/g) correlate inversely with polarization of NBD-phosphatidylcholine. Strong correlations were seen for both assays with the lecithin-sphingomyelin ratio and phosphatidylglycerol. The correlations indicate that the recommended reference range for FLM will have more false predictions of immaturity than the NBD-phosphatidylcholine assay.

Albumins↗
PubMed1991

Standing laser surgery of the head and neck.

The use of carbon dioxide and Nd:YAG lasers has expanded the capabilities of equine surgeons. These lasers are used to incise, vaporize, and coagulate tissue with minimal hemorrhage and reduced morbidity to the patient. In this article, practical fundamentals of laser surgery are briefly reviewed, and selected standing laser procedures of the head and neck are discussed.

Anesthesia, Conduction↗
PubMed1990

Lameness diagnosis and treatment in the Standardbred racehorse.

Lameness of the Standardbred racehorse is a function of rigorous training programs, year-round racing schedules, hard racetrack surfaces, and the draft load. In this article, principles of lameness diagnosis and treatment are reviewed, with emphasis upon common or unique problems of the trotter and pacer. The role of physical therapy as an adjunct to medical and surgical treatment of lameness is described. Options for management of chronic pain are discussed, and a limited glossary of descriptive terms that are unique to harness racing is provided.

Animals↗
PubMed1990

Measuring the number of lamellar body particles in amniotic fluid.

We describe a method for determining the number and size distribution of lamellar bodies and compare the results prospectively with other tests for fetal lung maturity: lecithin-sphingomyelin ratio (L/S), phosphatidylglycerol, and fluorescence polarization. The technique uses an electronic particle counter calibrated for a size range of 1.7-7.3 fL. The number of lamellar bodies in amniotic fluid samples varied from 3800-166,000 particles per microliter and correlated strongly with L/S ratio (r = 0.75; N = 144) and fluorescence polarization (r = -0.78; N = 165). Amniotic fluid samples stored for up to 10 days at 4C had stable lamellar body counts (within +/- 11%). Longer storage tended to decrease the counts. Addition of more than 1% (v/v) whole blood significantly decreased the lamellar body counts. This technique shows promise for the rapid assessment of fetal lung maturity.

Amniotic Fluid↗
PubMed1989

Carbon dioxide laser removal of a verrucous sarcoid from the ear of a horse.

A verrucous sarcoid was removed from the ear of a horse, using a carbon dioxide laser. The use of carbon dioxide laser excision and ablation enabled complete removal of tumor cells, with minimal damage to underlying normal cartilage. Cosmetic healing was observed with minimal disfigurement. Recurrence of the tumor was not observed after 11 months.

Animals↗
PubMed1987

Midline scrotal ablation technique for unilateral cryptorchid castration in horses.

Thirty-nine unilateral cryptorchid horses were castrated, using a midline scrotal ablation technique. This approach was satisfactory to access both inguinal rings, to eliminate the need for 2 incisions, and to allow for completion of the surgery by primary closure. These horses recovered from surgery with few complications, returned to work promptly, and had excellent cosmetic results.

Animals↗
PubMed1987

Reference frames in mental rotation.

Four experiments are reported that investigate whether images or reference frames are transformed during a mental rotation task. In all experiments a display of four identical letters (P1) was presented at either +90 degrees or -90 degrees from upright, and subjects had to decide whether the letters were normal or mirror-image reflections. A single letter (P2) was then presented 100 ms later in a variable orientation with the same task instructions. Reaction times to P2 were assessed to determine whether an image of P2 was rotated to upright or whether an internal reference frame was rotated into congruence with P2 from the orientation of P1. The results as a whole suggest that transformations of P2 can be initiated either relative to upright or relative to the orientation of P1. They further indicate that the probability of using each reference orientation can be changed by procedural variations. The findings are most parsimoniously interpreted as suggesting that mental rotation involves the transformation of reference frames rather than the transformation of template-like representations.

Attention↗
PubMed1986

Prevalence of carpal fractures in thoroughbred and standardbred racehorses.

The prevalence of carpal fractures was determined for 211 thoroughbred and 75 standardbred racehorses. Statistically significant differences were found in the location of fractures between the 2 breeds. In the thoroughbred and standardbred groups, total fractures (460) were distributed nearly equally between the left (224) and right (236) carpi. The most common site of fracture in the thoroughbred group was the distal aspect of the radiocarpal bone (112), whereas the most common site of fracture in standardbred horses was the proximal surface of the third carpal bone (61). Slab fractures were more common in the right carpus of thoroughbred horses (29 right/11 left), but were distributed equally between the left (11) and right (11) carpi of the standardbred group. Fractures of the distal border of the radius and intermediate carpal bone were more common in the left carpi of the thoroughbred group and were relatively uncommon among standardbred horses. Fractures within the intercarpal joints (313) were more common than those within the radiocarpal joints (147) in thoroughbred and standardbred horses.

Animals↗
PubMed1985

Separability and integrality of global and local levels of hierarchical patterns.

We used a constrained classification task to examine the perceptual relations between global and local levels in hierarchical patterns composed of many, relatively small elements and those composed of few, relatively large elements. In Experiments 1 and 3 subjects were asked to make classifications based on "form" or "texture." In Experiments 2 and 4 they were asked to classify according to the "shape" of the configuration or the elements. The results indicate that configural and elemental levels are perceptually separable for many-element patterns when processed as form and texture: Subjects could attend to either level without being affected by variation along the irrelevant dimension. However, when the same many-element patterns were processed for global and local shape, subjects could not selectively attend to either level. For few-element patterns, global configuration and local elements appeared to be perceptually integral dimensions. These results are relevant to two issues: the global precedence hypothesis and the explanations of integral and separable dimensions.

Adolescent↗
PubMed1978

Organizational factors in perceived dimensionality.

The hypothesis that perceived dimensionality of projection drawings is influenced by perceived organization was tested in two experiments. Organization was biased by coloration: The drawings were (a) uncolored, (b) colored in ways that emphasized plausible three-dimensional parts of the represented objects, or (c) colored in ways that emphasized two-dimensional (2D) parts of the drawings themselves. In Experiment 1, subjective ratings of three-dimensionality (3D) were greater for the 3D-biased stimuli than for the unbiased stimuli, and ratings for the 2D-biased stimuli were lower than for the unbiased stimuli. Similar results were obtained in Experiment 2 in which latencies to perceive the drawings three-dimensionally were measured. The 3D-biased stimuli were seen in depth more quickly than the unbiased stimuli, and the 2D-biased stimuli were seen in depth more slowly than the unbiased stimuli. Additional results on the relation between ratings and latencies suggest that latencies are affected more strongly by object complexity than are ratings.

Color Perception↗
PubMed1978

Orientation and symmetry: effects of multiple, rotational, and near symmetries.

Time to detect bilateral symmetry in different orientations was studied for closed polygons with single, double, quadruple, rotational, and near symmetry. In Experiment 1, the orientation of the axis of symmetry was varied. Detection was fastest for vertical symmetry, next fastest for horizontal, and slowest for left- and right-diagonal symmetries. For corresponding orientations, responses were faster to quadruple than double symmetries, and faster to double than single symmetries. Negative responses to nearly symmetric figures produced an orientation effect similar to that for single symmetries. Rotational symmetries showed no orientation effect and took longer to reject than near symmetries. In Experiment 2, subjects looked only for vertical symmetry. Responses were twice as fast as in comparable conditions of Experiment 1. The effect of multiple symmetries was still present, but rotational symmetries were rejected faster than near symmetries. The results are interpreted as supporting a dual process model for detecting symmetry in multiple orientation channels: Observers first select potential axes of symmetry defined by mirror-similar parts and then evaluate specific axes sequentially in a detailed comparison for mirror-identity.

Form Perception↗
PubMedDate not supplied

Arthroscopic removal of apical and abaxial sesamoid fracture fragments in five horses.

Five horses with apical and abaxial fractures of the proximal sesamoid bones were treated arthroscopically. Ipsilateral and contralateral triangulation were used to remove abaxial fragments; apical fragments were removed by ipsilateral triangulation. Excellent visibility of the fracture fragments was obtained with each method. Dissection and removal of fragments was accomplished with standard arthroscopic instruments, tendon-splitting knives, and curved scissors. Excellent functional and cosmetic results were achieved in all cases.

Animals↗