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S A Rose

Publications and source records attributed to S A Rose.

At least 37 records · Page 2Linked to original sources
PubMed1991

Strategies for the assessment of pediatric gait in the clinical setting.

Clinical gait analysis is a term that can be applied to numerous methods of evaluating a subject's walking pattern. These methods may include observation, videotaping, electromyography, kinematics, kinetics, and energetics. Modern gait analysis is based on the integration of these component methods of measurement to derive a complete analysis of gait. The data may then be used to help determine the treatment course of a patient with ambulatory problems or to document the effects of treatment. The purpose of this article is to provide an overview of the individual components of gait analysis. Emphasis will be placed on the type of information that can be derived from each component and how the information may be used clinically. Normal pediatric kinematics and kinetics are provided with literature references for phasic electromyography and temporal and stride variables. Two case examples illustrate the clinical utility of gait analysis information applied to cerebral palsy in surgical decision making and orthotic assessment. Guidelines are also provided for the referral of patients to a gait analysis laboratory.

Adolescent↗
PubMed1991

Asymmetries in infant cross-modal transfer.

3 groups of 12-month-olds were tested for cross-modal and intramodal transfer of information about shape. Infants were given either visual (V) or tactual (T) familiarization and then tested for visual recognition (V-V, T-V) or tactual recognition (T-T, V-T). Transfer was tested after either 15, 30, or 60 sec familiarization. Overall, intramodal transfer was superior to cross-modal transfer. Whereas the V-V condition was easiest of all, the T-T condition proved easier than V-T cross-modal transfer, although it was no more difficult than T-V transfer; cross-modal asymmetries appeared, with T-V easier than V-T. The asymmetry in cross-modal transfer could not be explained by intramodal factors. Possible bases for cross-modal asymmetries were discussed.

Female↗
PubMed1990

The effects of irradiation and temperature on the immunological activity of staphylococcal enterotoxin A.

The effects of irradiation and temperature on purified staphylococcal enterotoxin A were investigated using sensitive ELISA systems. Thermal inactivation of staphylococcal enterotoxin A in phosphate-buffered saline was considerably faster at temperatures of 60, 70, 115 and 121 degrees C than at 90 and 100 degrees C. In gelatin phosphate buffer, staphylococcal enterotoxin A was completely inactivated by irradiation at 8.0 kGy; in a 15% mince slurry, however, 27-37% of staphylococcal enterotoxin A remained at this level of irradiation. Even at a dose of 23.7 kGy, 16-26% residual staphylococcal enterotoxin A could still be detected. Generally, increasing the mince concentration increased the protection against the effect of irradiation on staphylococcal enterotoxin A. However, the protective effect of mince at a concentration of 50% was less than at a mince concentration of 30%. Both irradiation and heat processing of food should only be used in conjunction with good manufacturing practices to prevent proliferation of microorganisms and toxin productions.

Animals↗
PubMed1989

Characterization of cDNA clones encoding the extrinsic 23 kDa polypeptide of the oxygen-evolving complex of photosystem II in pea.

The 23 kDa polypeptide of the oxygen-evolving complex of photosystem II has been extracted from pea photosystem II particles by washing with 1 M NaCl and purified by anion-exchange chromatography. The N-terminal amino acid sequence has been determined and specific antisera have been raised in rabbits and used to screen a pea-leaf cDNA library in lambda gt11. Determination of the nucleotide sequence of two clones provided the nucleotide sequence for the full 23 kDa polypeptide. The deduced amino acid sequence showed it to code for a mature protein of 186 amino acid residues with an N-terminal presequence of 73 amino acid residues showing a high degree of conservation with previously reported 23 kDa sequences from spinach and Chlamydomonas. Southern blots of genomic DNA from pea probed with the labelled cDNA gave rise to only one band suggesting that the protein is encoded by a single gene. Northern blots of RNA extracted from various organs indicated a message of approximately 1.1 kb, in good agreement with the size of the cDNA, in all chlorophyll-containing tissues. Western blots of protein extracted from the same organs indicated that the 23 kDa polypeptide was present in all major organs of the plant except the roots.

Amino Acid Sequence↗
PubMed1989

Detection of staphylococcal enterotoxins in dairy products by the reversed passive latex agglutination (SET-RPLA) kit.

The SET-RPLA is a commercially available kit for the detection of staphyloccal enterotoxins in foods. Previous reports have shown that non-specific reactions occur on use of the kit with cheeses and thereby restrict its use. In this study a variety of dairy products were tested and non-specific reactions were found to be associated with those products rennetted during manufacture. These reactions can be obviated by addition of 10 mM sodium hexametaphosphate to the diluent provided in the kit, without affecting the ability to detect staphyloccal enterotoxins in dairy products. The sensitivity of the SET-RPLA was demonstrated to be 0.25 ng/ml.

Animals↗
PubMed1988

Studies on the irradiation of toxins of Clostridium botulinum and Staphylococcus aureus.

The effects of irradiation of Clostridium botulinum neurotoxin type A (BNTA) and staphylococcal enterotoxin A (SEA) in gelatin phosphate buffer and cooked mince beef slurries were investigated. Estimation of toxins by immunoassays showed that in buffer, toxins were destroyed by irradiation at 8.0 kGy; in mince slurries however, 45% of BTNA and 27-34% of SEA remained after this level of irradiation. At 23.7 kGy, over twice the dose of irradiation proposed for legal acceptance in the UK, 15% of BNTA and 16-26% of SEA still remained. Increasing concentrations of mince conferred increased protection against the effect of irradiation on both toxins. The biological activity of BNTA was more sensitive to irradiation than the immunological activity. Staphylococcal enterotoxin was more resistant to irradiation than BNTA. Irradiation should therefore only be used in conjunction with good manufacturing practices to prevent microbial proliferation and toxin production prior to irradiation.

Animals↗
PubMed1988

Shape recognition in infancy: visual integration of sequential information.

To investigate the integration of visual information across space and time, infants watched the contour of a shape being traced out by a moving point source of light and then viewed 2 objects: 1 with the shape they had just seen traced and 1 with a novel shape. In the first study, which varied the number of tracings (velocity about 16.7 cm/sec), 12-month-olds looked longer at the novel object in all conditions, indicating that they recognized the similarity between the alternative object and tracing of like contour. Study 2, which varied velocity (14.7 and 7.4 cm/sec), stimuli, and the number of tracings, provided evidence for the generalizability of these results but indicated that performance suffered at the slower speed. Studies 3 and 4 held velocity constant (14.7 cm/sec) while varying the size of the tracings and age of the infant: 12-month-olds, but not 6-month-olds, recognized figures in instances where it took up to 10 sec to complete a single tracing. Because it took so long to complete many of the tracings, central rather than purely retinal mechanisms appear to be involved in integrating shape in these situations.

Age Factors↗
PubMed1988

Individual differences in infants' information processing: reliability, stability, and prediction.

A group of 46 full-term and 54 high-risk preterm (less than 1,500 grams birthweight) infants were tested at 6, 7, and/or 8 months of age (corrected age for preterms) on a battery of problems assessing visual recognition memory and tactual-visual cross-modal transfer. At all 3 ages, scores obtained on aggregates of 6-11 problems in the battery significantly predicted 3-year Stanford-Binet IQ: correlations ranged from r = .37 to r = .63, and clustered between r = .50 and r = .60. When aggregates from 2 or 3 ages were used as predictors, multiple correlations were as high as R = .60 and R = .70. Cutoffs for predicting children at risk for mental retardation (IQ less than 70) or cognitive delay (IQ less than 85) showed reasonable sensitivity and specificity, although low scores were poor at detecting IQs less than 70. The internal consistency of composites, indexed by alpha coefficients, was unexpectedly low, primarily because the problems shared little variance. However, stability coefficients between assessments as much as 1 and 2 months apart were moderate in magnitude, ranging from r = .30 to r = .50. Considering the high degree of predictive validity, the stability figures appear to be better estimates of reliability for these measures than are indices of internal consistency. The relations reported here were similar for both full-terms and preterms.

Age Factors↗
PubMed1988

Information processing in seven-month-old infants as a function of risk status.

7-month-old full-terms and high-risk preterms (less than 1,500 grams at birth) were compared on problems of visual recognition memory and tactual-to-visual cross-modal transfer. On the visual problems, preterm infants showed significantly less differential attentiveness to novelty than full-terms. They also required longer exposure times during visual familiarization, primarily because of longer pauses between fixations. Preterms and full-terms exhibited different patterns of looking, as indicated by the duration of fixation and the frequency in shifts of gaze. On the cross-modal problems, preterms and full-terms both exhibited similar and significant preferences for familiar rather than novel stimuli, a direction of preference which suggests that these problems were relatively difficult for both groups. For the preterms, novelty and exposure-time scores were found to be related to several medical risk factors. Novelty preferences were compromised in preterms who had suffered RDS postnatally, particularly those who had required prolonged mechanical ventilation. In general, high-risk preterms exhibited deficits in visual recognition memory and in the ability to recruit, sustain, and shift attention.

Attention↗
PubMed1985

Visual recognition memory: a predictor of later cognitive functioning in preterms.

A number of preterms who had participated in a study of visual recognition memory when they were 6 months of age were seen at older ages to assess the predictive validity of the early visual measures for cognitive outcome. The Bayley scales were administered at 6, 12, and 24 months, the Stanford-Binet at 34 and 40 months, and the WISC-R at 6 years. Novelty scores, which reflect the relative amount of time infants look at new compared to familiar stimuli, constituted the measure of infant visual processing. These scores, obtained by averaging over performance on the 3 or 4 problems administered at 6 months of age, were consistently and significantly related to cognitive measures from 24 months to 6 years, with correlations ranging from r = .53 to r = .66. Parental education, which was unrelated to novelty scores, bore a strong relationship to outcome beginning at 24 months. Although both measures contributed uniquely to the variance in cognitive outcome at 24 months and 6 years, visual novelty scores made a stronger contribution than did parental education. Neither 6- nor 12-month Bayley scores, nor various perinatal variables, were related to outcome.

Child Development↗
PubMed1983

Differential rates of visual information processing in full-term and preterm infants.

This study investigated the effect of increasing familiarization time on the visual recognition memory of 6- and 12-month-old full-term and preterm infants. Infants were given trials in which they viewed a shape for either 10-, 15-, 20-, or 30-sec familiarization and were then tested for visual recognition memory using the paired comparison technique. While the older infants showed evidence of recognition memory after less familiarization time than the younger ones, at both ages preterms required considerably longer familiarization than full-terms. The pattern of performance replicates our earlier finding of developmental lags in the visual information processing of 6-month-old preterms and extends these findings to 12-month-olds. These results suggest that there are persistent differences between preterm and full-term infants throughout at least the first year of life in this very fundamental aspect of cognition.

Female↗
PubMed1983

Infants' cross-modal transfer from solid objects to their graphic representations.

12-month-old infants were familiarized either tactually or visually with objects and then tested for visual recognition memory using either (1) the familiar and a novel object, (2) colored pictures of the objects, or (3) outline drawings of them. In Study 1, infants showed recognition memory on all 3 visual intramodal problems but showed cross-modal transfer only when objects were used as test stimuli. With increased familiarization times in Study 2, transfer from tactually presented samples to both pictorial displays was achieved, indicating that after feeling an object the infants were able to recognize it visually solely on the basis of its contour. With reduced familiarization times in Study 3, there was no evidence for transfer from visually presented samples to the 2 pictorial displays, replicating the pattern of results observed cross-modally in Study 1 and suggesting that, at least in certain respects, cross-modal and intramodal perception follow similar principles.

Depth Perception↗
PubMed1981

Developmental changes in infants' retention of visual stimuli.

In the first of 2 studies of visual recognition memory, 6- and 9-month-old infants were tested for their ability to differentiate novel from familiar test stimuli immediately following brief amounts of familiarization. After all problems were given, the paired test stimuli were re-presented for a test of delayed recognition memory. The delay test thus occurred after a period during which the infant had been looking at a number of different intervening stimuli. The 6- and 9-month-olds both showed significant recognition memory on 3 of the problems immediately following familiarization. While the older infants continued to show recognition on each of these problems after a delay, the younger infants failed to show evidence of retention on 2 of the 3 problems they had been able to recognize initially. In a second study, 6-month-olds were tested for delayed recognition under conditions where the interval between the familiarization and test was free of any interpolated visual stimuli. Despite this effort to minimize interference, the pattern of responding remained virtually identical to that of the first study. Thus the 6-month-olds appeared to have difficulty recognizing the stimuli over short delays, even in the absence of intervening distractors. The greater capacity for delayed recognition memory among the 9-month-olds is discussed in terms of other memory changes that may be taking place at that age.

Age Factors↗
PubMed1980

Tactile recognition memory in infants.

This experiment was conducted to determine whether infants can recognize the shapes of objects by touch alone. 25 1-year-olds were administered 2 tasks, each of which consisted of a familiarization stage followed by a recognition test stage. The familiarization stage of both tasks was identical in that infants manipulated objects in the light. The test stages differed with respect to the lighting conditions. In the first task infants manipulated familiar and novel objects in the light, and in the second task, in darkness. Behavior in darkness was videotaped by infrared recording. Recognition memory was determined by infants' differential manipulatory responsiveness to novel and familiar objects. In both the lighted and darkness tests infants engaged in significantly more manipulation, exhibited more mouthing, and displayed more hand-to-hand transfers with novel compared to familiar objects. These data provide initial evidence that infants are capable of tactile recognition memory.

Discrimination Learning↗
PubMed1980

Effects of prematurity and early intervention on responsivity to tactual stimuli: a comparison of preterm and full-term infants.

Cardiac and behavioral responses to a tactual stimulus were evaluated during the first sleep cycle for 3 groups of infants: 30 full terms, 30 nonintervened preterms, and 30 intervened preterms. Prior to testing, the latter group had received a regimen of multimodal sensory stimulation, which emphasized the tactual and vestibular modalities. The results showed that the intervention altered the preterms' sensory functioning mainly during active sleep. In this state, the full terms and the intervened preterms exhibited a significant cardiac acceleration to the stimulus, while the nonintervened preterms failed to do so. Similarly, the behavioral response of the intervened preterm more closely approximated that of the full terms. During quiet sleep the intervention did not affect either the cardiac or the behavioral response. In this sleep state, the full terms' cardiac response was that of monophasic acceleration, whereas both groups of preterms exhibited a biphasic response with a smaller initial acceleration which was followed by a deceleration below baseline. Behaviorally, the preterms responded less frequently and gave smaller responses than the full terms. Thus there were marked differences between preterms and full terms, and the intervention seemed to narrow this gap to some extent.

Female↗