PubMed Health⌕ Search

Biomedical subjects

B Edelman

Publications and source records attributed to B Edelman.

At least 19 recordsLinked to original sources
PubMed1999

From rotation to disfiguration: testing a dual-strategy model for recognition of faces across view angles.

A study is reported of the effect of distinctive marks on the recognition of unfamiliar faces across view angles. Subjects were asked to memorize a set of target faces, half of which had distinctive marks. Recognition was assessed by presenting the target faces, either in the same orientation, or after 90 degrees rotation, mixed with an equal number of distractors. Results show that the effect of distinctive marks depends on the view presented during learning. When a frontal view was learned, as predicted by the dual-strategy model [Valentin et al, in press, in Computational, Geometric, and Process Perspectives on Facial Cognition: Context and Challenges Eds T Wenger, J Townsend (Hillsdale, NJ: Lawrence Erlbaum Associates)], distinctive marks improve recognition performance in the 90 degrees condition but not in the 0 degree condition. However, when a profile view was learned, distinctive marks have no effect on recognition performance, even in the 90 degrees condition where a frontal view is tested.

Face↗
PubMed1998

Circumflex coronary artery dissection following waterskiing.

A previously healthy 35-year-old woman experienced chest discomfort following mild blunt chest trauma while waterskiing. During the following 48 h, she underwent evaluation in two separate emergency departments (EDs) where she was found to have normal ECGs and cardiac enzyme values. She was subsequently discharged from both EDs. Twelve hours after the second ED visit, she was discovered unconscious at home and was resuscitated from ventricular fibrillation. Emergency cardiac catheterization demonstrated moderate circumflex disease without angiographic evidence of a false lumen or intimal flap. Left ventriculography demonstrated posterolateral wall hypokinesis. Eight days after remaining ventilator-dependent and unconscious, the patient was declared brain-dead. At autopsy, the patient was found to have a dissection of the circumflex artery. Waterskiing is an unusual source of cardiac trauma; however, we believe this to be the first reported case of dissection in the circumflex artery following blunt chest trauma.

Adult↗
PubMed1997

Principal Component and Neural Network Analyses of Face Images: What Can Be Generalized in Gender Classification?

We present an overview of the major findings of the principal component analysis (pca) approach to facial analysis. In a neural network or connectionist framework, this approach is known as the linear autoassociator approach. Faces are represented as a weighted sum of macrofeatures (eigenvectors or eigenfaces) extracted from a cross-product matrix of face images. Using gender categorization as an illustration, we analyze the robustness of this type of facial representation. We show that eigenvectors representing general categorical information can be estimated using a very small set of faces and that the information they convey is generalizable to new faces of the same population and to a lesser extent to new faces of a different population. Copyright 1997 Academic Press. Copyright 1997 Academic Press

Journal Article↗
PubMed1997

What represents a face? A computational approach for the integration of physiological and psychological data.

Empirical studies of face recognition suggest that faces might be stored in memory by means of a few canonical representations. The nature of these canonical representations is, however, unclear. Although psychological data show a three-quarter-view advantage, physiological studies suggest profile and frontal views are stored in memory. A computational approach to reconcile these findings is proposed. The pattern of results obtained when different views, or combinations of views, are used as the internal representation of a two-stage identification network consisting of an autoassociative memory followed by a radial-basis-function network are compared. Results show that (i) a frontal and a profile view are sufficient to reach the optimal network performance; and (ii) all the different representations produce a three-quarter view advantage, similar to that generally described for human subjects. These results indicate that although three-quarter views yield better recognition than other views, they need not be stored in memory to show this advantage.

Computer Simulation↗
PubMed1996

Ninety-six-hour paclitaxel infusion after progression during short taxane exposure: a phase II pharmacokinetic and pharmacodynamic study in metastatic breast cancer.

PURPOSE: A phase II trial of paclitaxel infused over 96 hours in patients with metastatic breast cancer with demonstrated disease progression (PD) during short-infusion taxane treatment was performed to evaluate schedule-dependent activity with prolonged drug exposure. The tolerability of this strategy and its pharmacokinetic profile and pharmacodynamic correlates were also investigated. PATIENTS AND METHODS: Paclitaxel was administered to 26 patients with metastatic breast cancer at 120 to 140 mg/m2 intravenously over 96 hours. Twenty-three patients had demonstrated PD while receiving prior 3-hour paclitaxel, two during 1-hour docetaxel, and one during infusions of docetaxel and then paclitaxel. Twenty-one patients (81%) had no prior response to the short taxane infusion (primary resistance) and five (19%) had prior partial responses (PRs) of brief duration before PD (secondary resistance). Plasma paclitaxel concentrations were assessed at 24, 48, 72, and 96 hours. RESULTS: After delivery of 195 cycles, seven of 26 assessable patients (26.9%; 95% confidence interval, 11.6% to 47.8%) had major objective responses, with a median response duration of 6 months (range, 1 to 13). The predominant toxicities were neutropenia (76% grade > or = 3) and stomatitis (15% grade > or = 3). Despite omission of premedications, no significant hypersensitivity reactions occurred. The median steady-state paclitaxel concentration (Css) in 23 assessable patients was 0.047 mumol/L (range, .023 to .176). Patients who experienced grade 4 neutropenia had significantly decreased paclitaxel clearance and higher Css than those with grade 1 to 3 neutropenia (P < .05). Pretreatment elevation of hepatic transaminases was associated with delayed clearance (P < .01) and increased myelo-suppression and mucosal toxicity. CONCLUSION: Paclitaxel demonstrates activity against metastatic breast cancer when administered over 96 hours to patients with disease that recently had progressed during short taxane exposure. Delayed paclitaxel clearance and consequent increased toxicity occurred in patients with hepatic dysfunction. The activity observed supports preclinical data that suggest variability in efficacy and resistance patterns to paclitaxel based on duration of exposure.

Adult↗
PubMed1995

More about the difference between men and women: evidence from linear neural networks and the principal-component approach.

The ability of a statistical/neural network to classify faces by sex by means of a pixel-based representation has not been fully investigated. Simulations with pixel-based codes have provided sex-classification results that are less impressive than those reported for measurement-based codes. In no case, however, have the reported pixel-based simulations been optimized for the task of classifying faces by sex. A series of simulations is described in which four network models were applied to the same pixel-based face code. These simulations involved either a radial basis function network or a perceptron as a classifier, preceded or not by a preprocessing step of eigendecomposition. It is shown that performance comparable to that of the measurement-based models can be achieved with pixel-based input (90%) when the data are preprocessed. The effect of the eigendecomposition preprocessing of the faces is then compared with spatial-frequency analysis of face images and analyzed in terms of the perceptual information it captures. It is shown that such an examination may offer insight into the facial aspects important to the sex-classification process. Finally, the contribution of hair information to the performance of the model is evaluated. It is shown that, although the hair contributes to the sex-classification process, it is not the only important contributor.

Algorithms↗
PubMed1993

Sequential measurement of anti-platelet antibodies in a patient who developed EDTA-dependent pseudothrombocytopenia.

Ethylenediaminetetraacetic acid (EDTA)-dependent pseudothrombocytopenia is the occurrence of a falsely low platelet count caused by antibodies that agglutinate platelets in the presence of EDTA. If unrecognized, it may result in the erroneous diagnosis of thrombocytopenia and possible inappropriate therapy. It has been noted that this phenomenon tends to appear in hospitalized patients after an initially normal platelet count, but sequential measurements of anti-platelet antibody have not been reported. The case of a patient who developed EDTA-dependent pseudothrombocytopenia approximately 1 week after being hospitalized for severe trauma is described. Anti-platelet antibodies were not detected on admission by a radiolabeled antiglobulin technique but were shown to increase in titer concurrent with the appearance of EDTA-dependent pseudothrombocytopenia.

Autoantibodies↗
PubMed1986

Environmental effects on the intake of overweight and normal-weight men.

The effects of changes in portion size and social condition on food intake were compared for overweight and normal-weight men. Subjects believed they were participating in a luncheon test of the acceptability of lasagna. In Study 1, under conditions designed to mimic social dining in a cafeteria, subjects were given either 255 or 426 g of lasagna. All subjects at a particular session received the same size portion and could ask for as many helpings as they wished. While overweight subjects ate more than normal-weight subjects, changes in portion size had no significant effects on intake. In Study 2, the effects of social vs. isolated dining were compared. Overweight subjects ate more than normal-weight subjects, and both overweight and normal-weight subjects eating socially ate more than subjects eating alone. In both studies there was a significant relationship between preference rating and intake for overweight subjects but not for normal-weight subjects. The results support the existence of differences in intake between overweight and normal-weight individuals and also indicate the potential importance of environmental factors in the intake of both groups.

Adult↗
PubMed1986

Effect of spironolactone on acute mountain sickness.

This study examined the effectiveness of spironolactone as a prophylactic agent for the prevention of acute mountain sickness (AMS). Spironolactone, 25 mg PO QID, or placebo was administered to nine subjects in a double-blind, placebo-controlled, crossover design. Medication was given for 48 h prior to and during a 46-h exposure to 427 mm Hg (4570 m) in a hypobaric chamber. Six subjects demonstrated prevention of either the cerebral or respiratory symptoms of AMS during at least one segment of the altitude sojourn.

Acute Disease↗
PubMed1985

Changes in fibronectin synthesis and binding distribution in SV40-transformed human keratinocytes.

We have studied the synthesis and distribution of fibronectin in human epidermal keratinocytes infected by SV40, a system in which the acquisition of transformed properties occurs in a sequential and progressive manner. Immunofluorescence studies showed that cultured uninfected keratinocytes do not exhibit fibronectin on the superficial cell surface, but that virus-infected cells come to display superficial fibronectin-containing cables in a density-dependent manner after a certain point in the transformation process. In contrast, organized arrays of fibronectin-containing fibrils associated with the cell-substrate attachment complex were seen in uninfected keratinocytes and in virus-infected cells at all stages of the transformation process. Studies of fibronectin synthesis using metabolic labelling of cell proteins with 35S methionine showed that viral infection caused a striking increase in overall fibronectin synthesis, although with a much higher proportion of newly synthesized fibronectin being secreted into the cell culture medium than in the case of the uninfected cells.

Cell Line↗
PubMed1982

Facts and fictions about infantile obesity.

This review assesses the present state of knowledge on the etiology of infantile obesity. Current controversies such as bottle vs. breast feeding, the importance of differences in early feeding and activity patterns, and the role of early adipose cell development are discussed. There is continuing debate on the relationship of early obesity to later body weight. The major limitation of current research is the lack of adequate consideration of social and environmental factors particularly how eating and activity behaviors develop and are maintained. The emphasis of this paper is on highlighting the opportunities for different learning experiences inherent in different feeding environments during early life. Implications for research particularly the need for longitudinal studies on the establishment of characteristic eating and activity patterns are discussed.

Adipose Tissue↗
PubMed1982

Development differences in the conceptualization of obesity.

Development differences in the conceptualization of obesity were investigated in children ranging in age from 5 to 11 years. Perceived causes, cures, and attitudes about obesity were assessed through individual interviews. Answers differed in content as well a complexity. A preliminary category system was developed to describe these differences. Responses showed certain consistencies, particularly the emphasis on certain foods as the cause of overweight and the negative perception of obesity. The implications of these findings for nutrition education programs are discussed.

Age Factors↗
PubMed1981

Evaluation of the new Beckman electrophoretic method for CK-MB: comparison with ion exchange chromatography and investigation of a reference outpatient population.

We evaluated the performance of a CK isoenzyme kit utilizing agarose electrophoresis with fluorescence scanning of an overlay paper rather than the gel. We compared this method to ion exchange chromatography with mini-columns of DEAE Sephadex using samples from hospitalized patients and from a reference population of ambulatory outpatients with common, chronic medical conditions. The detection limit, precision and linearity of the electrophoretic method were acceptable, but the method overestimated CK-MB, requiring a different reference range for clinical application. There were inter-racial differences within the reference population for total CK and for the percent of CK-MB using either method. We discuss the significance of our findings with respect to clinical decision limits for CK-MB.

Adult↗
PubMed1981

Multifocal malignant pheochromocytoma presenting as a lung tumor.

An unusual case of pheochromocytoma, which presented as a primary lung tumor, is described. The tumor was multifocal, arising in both the adrenal glands and in the chromaffin tissue around the thoracic aorta; it had invaded the lung and metastasized to the brain. Histologically the tumor had an unusual sarcomatous appearance, and the final diagnosis depended on the ultrastructural finding of scanty amounts of neurosecretory granules, typical of epinephrine and norepinephrine. This is the first reported case of pheochromocytoma presenting clinically as a lung tumor.

Adrenal Gland Neoplasms↗