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Biomedical subjects

L M Herman

Publications and source records attributed to L M Herman.

18 recordsLinked to original sources
PubMed1990

Bottlenosed dolphin and human recognition of veridical and degraded video displays of an artificial gestural language.

2 bottlenosed dolphins proficient in interpreting gesture language signs viewed veridical and degraded gestures via TV without explicit training. In Exp. 1, dolphins immediately understood most gestures: Performance was high throughout degradations successively obscuring the head, torso, arms, and fingers, though deficits occurred for gestures degraded to a point-light display (PLD) of the signer's hands. In Exp. 2, humans of varying gestural fluency saw the PLD and veridical gestures from Exp. 1. Again, performance declined in the PLD condition. Though the dolphin recognized gestures as accurately as fluent humans, effects of the gesture's formational properties were not identical for humans and dolphin. Results suggest that the dolphin uses a network of semantic and gestural representations, that bottom-up processing predominates when the dolphin's short-term memory is taxed, and that recognition is affected by variables germane to grammatical category, short-term memory, and visual perception.

Animal Communication↗
PubMed1989

Different 3' end regions strongly influence the level of gene expression in plant cells.

We have investigated the functional role of a 3' end region on the expression of a reporter gene in plant cells. In stably transformed plants, expression of the reporter gene without a plant gene 3' end is variable and depends on the fortuitous presence of polyadenylation signals in the downstream sequences. When the reporter gene is flanked by pBR322 DNA, 3'-processing and polyadenylation occurs at (a) cryptic site(s) within these vector sequences. Using a transient gene expression system, we present a deletion analysis of the 3' end of the octopine synthase gene showing that the most proximal polyadenylation signal per se is not sufficient to ensure expression but that a downstream (G)T-rich sequence is also required. Optimal expression of the fusion gene requires more than 98 base pairs and at most 142 base pairs downstream from the most distal polyadenylation site. We analyzed the expression of chimeric genes with 3' end sequences originating from different plant genes. In the transient expression assay, all constructs direct similar neomycin phosphotransferase II activities. However, in stably transformed tissue, the gene constructs displayed characteristic expression levels which varied as much as 60-fold. This result suggests a role for 3' end sequences in post-transcriptional processes such as efficiency of 3'-processing and/or mRNA stability.

Amino Acid Oxidoreductases↗
PubMed1987

Immunohistochemical localization of substance P and enkephalin in the nucleus tractus solitarii of the rhesus monkey, Macaca mulatta.

The nucleus tractus solitarii in the monkey Macaca mulatta was found to have several subdivisions based upon cytoarchitectonics and immunohistochemistry. Subdivisions that could be identified included commissural, medial, parvicellular, dorsolateral, ventrolateral, intermediate, and interstitial. Substance P and enkephalin immunoreactivity was localized within discrete regions of the nucleus tractus solitarii, by means of the peroxidase-antiperoxidase technique. Substance P immunoreactivity occurred most frequently in the interstitial subdivision of the nucleus tractus solitarii. Moderate accumulations of substance P immunoreactivity were present in the commissural, medial, parvicellular, dorsolateral, and intermediate subdivisions, but very little was present in the ventrolateral subdivision. Enkephalin immunoreactivity followed the staining patterns of substance P; however, the amounts of enkephalin immunoreactivity were less than amounts for substance P. Following colchicine treatment, large numbers of enkephalin-immunoreactive neurons were distributed throughout all subdivisions, many being located in the parvicellular and medial subdivisions. The few substance P-immunoreactive neurons found were restricted to the parvicellular subdivision. The distribution of substance P and enkephalin immunoreactivity in M. mulatta is very similar to that described in the cat and rat. In addition, the extensive overlap of the distribution of these two putative neurotransmitters provides morphological evidence for their possible participation in the autonomic regulation within the nucleus tractus solitarii.

Animals↗
PubMed1986

Status of stroke patients: a community assessment.

The identification of norms relating to the status of stroke patients is significant to community plans to provide contemporary health services for stroke patients. This two-phase research study assessed the status of stroke patients for a large metropolitan area. The first phase of research was a retrospective hospital record review conducted on 1,665 subjects admitted to 13 Cincinnati hospitals with the primary diagnosis of stroke. This study showed that the Cincinnati outcomes were consistent with the outcomes demonstrated in the literature. The most typical stroke patient was a 71-year-old woman with right hemiplegia, who was living at home with another adult after spending 17.5 days in the acute care hospital. The behavioral functional levels of 105 disabled stroke patients were assessed in the second phase, using the Level of Rehabilitation Scale. Subjects were analyzed in five functional areas to determine their level of independent living. Demographic data were used to analyze the findings in comparisons. In general, stroke patients function higher in activities of daily living than they do in social interactions. Stroke patients living with another adult demonstrated a lower degree of functioning in activities of daily living than those who lived alone, but scored higher in social interactions.

Activities of Daily Living↗
PubMed1986

Isolation of tobacco DNA segments with plant promoter activity.

We constructed a promoter probe vector, pGVL120, to isolate plant DNA segments with promoter activity in tobacco. Plant nuclear DNA Sau3A fragments were inserted in front of the npt-II sequence, and a mixture of recombinant plasmids was mobilized to Agrobacterium sp. and used to transform tobacco protoplasts. By kanamycin selection, transformed plant cell lines containing NPT-II T-DNAs were isolated. Eight of these cell lines were regenerated and analyzed for the levels of NPT-II activity in stem, root, midrib, and leaf. These levels demonstrated novel regulation patterns in each isolate. One cell line, T20, was analyzed in detail and found to contain four different T-DNAs. One of the recloned T-DNAs, T20-2, contains an insert of 401 base pairs in front of the NPT-II sequence, and by reintroducing this T-DNA into plant cells we could demonstrate that this insert provides a promoter sequence. The NPT-II enzyme activity under the control of the P20 promoter is especially high in stem and root, but low in leaf and callus, both in the originally isolated T20 plant and in independently isolated transformants with the T20-2 T-DNA.

Base Sequence↗
PubMed1985

Reporting presence or absence of named objects by a language-trained dolphin.

Referential "reporting" was defined as the transmission of information about the presence or absence of symbolically-referenced real-world objects. In Experiment 1 two bottlenosed dolphins (Tursiops truncatus), trained in earlier studies to carry out instructions conveyed by imperative sentences expressed in artificial gestural or acoustic languages, each gave spontaneous indications that an object referenced in an imperative was absent from their tank. In Experiment 2 the dolphin tutored in the gestural language was taught to make explicit reports of object absence by pressing a "No" paddle in response to imperatives referencing an absent object. Absence was reported correctly on 84% of 97 missing-object probes inserted at random intervals among 598 sentences referring to objects that were present. Reports were typically made after active search of the tank for an average of 15.0 sec. False reports, that objects present were absent, were few (7.5%). In Experiment 3, the dolphin was taught an interrogative sentence form that enabled us to ask direct questions about the presence or absence of specific objects. Responses by the dolphin on the No paddle indicated absence, while responses on a "Yes" paddle indicated presence. From one to three objects were shown the dolphin and then placed in the tank in a discrete-trial procedure. In response to the interrogative, reports or object presence or absence were better than 91% correct with a single object in the tank and either that object or some other object referenced; accuracy declined to 72-78% correct with three objects present, but was still well above chance. Several lines of evidence suggested that the dolphin was attempting to remember which objects it had been shown, rather than conducting an active environmental search as in Experiment 2. The memory strategy became less efficient as the number of objects to be remembered increased. Overall, the results evidenced the language-trained dolphin's understanding of references to present or absent objects, its ability to inventory its environment to seek information about those objects, and its ability to report its obtained knowledge to others.

Animal Communication↗
PubMed1984

Vocal mimicry of computer-generated sounds and vocal labeling of objects by a bottlenosed dolphin, Tursiops truncatus.

A bottlenosed dolphin (Tursiops truncatus) was trained to mimic computer-generated "model" sounds, using a whistle mode of vocalization. Prior to training, the whistle sounds of this dolphin were limited to a few stereotyped forms, none of which resembled the model sounds. After training, high-fidelity imitations were obtained of model sounds having (a) moderately or widely swept, slow-rate frequency modulation (1-2 Hz), (b) narrowly or moderately swept frequency modulation at moderate to rapid rates (3-11 Hz), (c) square-wave frequency transitions, and (d) unmodulated (pure-tone) waveforms. New models, not heard previously, could be mimicked immediately, often with good fidelity, including mimicry of amplitude variation that had not been explicitly reinforced during training. Subsets of familiar models were mimicked with high reliability in repeated tests. In additional training, control of the mimic response was transferred from the acoustic model to objects shown the dolphin (e.g., a ball or a hoop) so that, in effect, the dolphin gave unique vocal labels to those objects. In a test of accuracy and reliability of labeling, correct vocal labels were given on 91% of 167 trials comprised of five different objects presented in random order. The dolphin's ability for vocal mimicry compared favorably with that of the more versatile mimic birds, and it contrasted sharply with the apparent lack of vocal mimicry ability in terrestrial mammals other than humans. The ability to label objects vocally was similar to abilities shown for some birds and similar, in principle, to abilities of great apes trained in visual languages to label objects through gestures or other visual symbols.

Animals↗
PubMed1977

Memory for lists of sounds by the bottle-nosed dolphin: convergence of memory processes with humans?

After listening to a list of as many as six discriminably different 2-second sounds, a bottle-nosed dolphin classified a subsequent probe sound as either "old" (from the list) or "new." The probability of recognizing an old probe was close to 1.0 if it matched the most recent sound in the list and decreased sigmoidally for successively earlier list sounds. Memory span was estimated to be at least four sounds. Overall probabilities of correctly classifying old and new probes corresponded closely, as if recognition decisions were made according to an optimum maximum likelihood criterion. The data bore many similarities to data obtained from humans tested on probe recognition tasks.

Animals↗
PubMed1975

Bottle-nosed dolphin: double-slit pupil yields equivalent aerial and underwater diurnal acuity.

In bright daylight, and at best viewing distances, the bottlenosed dolphin resolves visual gratings approximately equally well in air and in water. Aerial resolution improves with increased viewing distance, while underwater resolution improves with decreased viewing distance. The double-slit pipil overcomes the gross myopia in air measured by ophthalmoscope and produces the indicated effects of viewing distance.

Air↗
PubMed1974

Auditory delayed matching in the bottlenose dolphin.

A bottlenose dolphin, already highly proficient in two-choice auditory discriminations, was trained over a nine-day period on auditory delayed matching-to-sample and then tested on 346 unique matching problems, as a function of the delay between the sample and test sounds. Each problem used new sounds and was from five to 10 trials long, with the same sound used as the sample for all trials of a problem. At each trial, the sample was projected underwater for 2.5 sec, followed by a delay and then by a sequence of two 2.5-sec duration test sounds. One of the test sounds matched the sample and was randomly first or second in the sequence, and randomly appeared at either a left or right speaker. Responses to the locus of the matching test sound were reinforced. Over nine, varying-sized blocks of problems, the longest delay of a set of delays in a block was progressively increased from 15 sec initially to a final value of 120 sec. There was a progressive increase across the early blocks in the percentage of correct Trial 1 responses. A ceiling-level of 100% correct responses was then attained over the final six blocks, during which there were 169 successive Trial 1 responses bracketed by two Trial 1 errors (at 24- and 120-sec delays). Performance on trials beyond the first followed a similar trend. Finally, when the sample duration was decreased to 0.2 sec or less, matching performance on Trial 1 of new problems dropped to chance levels.

Acoustic Stimulation↗