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PubMed1998

Effectiveness of redundant color coding in multidimensional identification.

This study investigated the effectiveness of redundant color coding in multidimensional identification. Statistical analysis showed that redundant color in multidimensional identification did not necessarily improve performance and response speed might even deteriorate if subjects were not informed of the use of redundant color. Merely informing subjects of the use of redundant color might not benefit identification speed either; subjects had to actually use color in responding to facilitate response speed. Further, redundant color might be more appropriate to associate with the less-salient or the less-familiar stimulus attribute. Implications of the results for the design of multidimensional display and for human information processing were discussed.

Adult↗

PubMed2001

Locus of the redundant-signals effect in bimodal divided attention: a neurophysiological analysis.

We reanalyzed the data from the study of Lamarre, Busby, and Spidalieri (1983). In that study, the activity of single neurons in area 4 of the motor cortex was recorded during a bimodal detection task in which a monkey (Macaca mulatta) had to respond as quickly as possible to a visual or an auditory signal or to both (redundant trials). Manual responses on redundant trials were speeded by the presence of both signals, as is typically found. The times between signal onsets and the first changes in neuronal activity were also speeded by redundant signals, but there was no difference between redundant-signals and single-signal trials in the time between the change in neuronal activity and movement onset. These results suggest that late motor processes are not speeded by redundant signals in bimodal detection tasks.

Animals↗

PubMed2004

Effects of redundant visual stimuli on temporal order judgments.

Four experiments were conducted in order to compare the effects of stimulus redundancy on temporal order judgments (TOJs) and reaction times (RTs). In Experiments 1 and 2, participants were presented in each trial with a tone and either a single visual stimulus or two redundant visual stimuli. They were asked to judge whether the tone or the visual display was presented first. Judgments of the relative onset times of the visual and the auditory stimuli were virtually unaffected by the presentation of redundant, rather than single, visual stimuli. Experiments 3 and 4 used simple RT tasks with the same stimuli, and responses were much faster to redundant than to single visual stimuli. It appears that the traditional speedup of RT associated with redundant visual stimuli arises after the stimulus detection processes to which TOJs are sensitive.

Adult↗

PubMed1992

What makes targets redundant?

Two letter-classification experiments that investigated target-redundancy effects on reaction time (RT) were conducted. Both experiments were replicated with choice reaction time (CRT) and go/no-go (GNG) procedures. In each experiment, there were two single-target conditions, one with a noise letter and one without. In one experiment, the letter classes were two letters that could be of either case. In the second experiment, each class consisted of two different capital letters. In both experiments, there were two redundant-targets conditions, one with identical targets and one with the different members of a class. In both of the GNG experiments, redundancy gains were obtained comparing the different-targets condition with the no-noise, single-target condition. Redundant stimuli are ones that lead to the same response. Visually different stimuli may be processed in parallel and jointly activate a response. GNG procedures are more sensitive than CRT in the investigation of redundancy effects.

Adult↗

PubMed1987

[The health of industrial employees four years after compulsory redundancy].

A controlled, longitudinal study of the health of workers made redundant when a meat products factory closed has been performed using morbidity data extracted from the records of a group general practice. Increases in consultation rates and the number of visits to hospital outpatient departments in the group made redundant are contrasted with opposite trends in a control group who remained securely employed. As in earlier findings, the increases in morbidity in the study group began when they learned that their jobs were in jeopardy.The subsequent employment history of those made redundant was obtained by questionnaire. In the four years after redundancy, 50 of the 76 men in-the study group found new full-time jobs. The other 26 men remained out of work for most of this time or were made redundant once again. This 'jobless' group consulted their general practitioners 57% more often about 13% more illnesses, were referred to hospital outpatient departments 63% more often and visited hospital 208% more frequently than when enjoying secure employment. During an intervening two-year period of job insecurity, there were increases of 45%, 9%, 25% and 28% respectively, for this jobless group.The implications of these findings for primary care, for the National Health Service and for future research are discussed in the present context of high levels of unemployment.

England↗

PubMed1993

[Comparative redundancy of genes of various organisms and viruses].

This paper is devoted to the comparative study of redundancy of genetic texts of various organisms and viruses. To determine the redundance of a gene, we have introduced the strict measure for that latter. The measure for a text's redundance is the length of restriction of Frequency/Correlation Dictionary of a given genetic text. Frequency/Correlation Dictionary is the ser of all subsequences belong to a given genetic text, accompanied by the frequencies of their occurrence. The restriction length is defined as that one, for which all the subsequences (of that length) are unique. We have found, that genes of human viruses are less redundant, in comparison to those of human genes. Other aspects of a comparative redundance investigations of the genes are discussed. The problem of the determination of "truet" intron could be treated by this methodology, as well, as the evolution of genome.

Amino Acid Sequence↗

PubMed1995

[Introns differ from exons by their redundancy].

This paper is devoted to an analysis of the intrinsic structure of the gene from the point of view of the redundancy of different structural units--exons and introns. Human genes for which the exon-intron structure has been clearly established were studied. The redundancy of each exon and intron in the gene was determined. It was shown that, in human genes, introns are more redundant than exons. Redundancy is determined as the smallest length of a word (oligonucleotide) beginning with which all words in the studied nucleotide sequence are found exactly once. Mechanisms leading to the disruption of the general pattern of ratios of redundancy of exons and introns are studied.

Base Sequence↗

PubMed1984

Redundancy and complexity of information in cognitive performances of schizophrenic and normal individuals.

Examined cognitive performance of schizophrenic and normal Ss matched on age, education, and intelligence (N = 120). Complexity of information and redundant cues were manipulated systematically in a concept identification (CI) task. Schizophrenics were not impaired compared to normals in solution of problems with low redundancy. Whereas normals' performance was facilitated by redundant information, schizophrenics demonstrated marked deficit in CI as a function of that information. Results were interpreted in terms of schizophrenics' inability to filter out irrelevant information, in addition to their deficit in channel capacity for utilizing relevant-redundant cues, which have been shown to reliably facilitate normals' CI.

Adult↗

PubMed2006

The "pull-push" technique to deal with a redundant eustachian valve interfering with placement of a PFO occluder.

OBJECTIVES: To evaluate the role of a new technique to deal with a redundant Eustachian valve (EV) interfering with placement of a patent foramen ovale (PFO) occluder. BACKGROUND: The EV is a remnant of the embryonic valve of the sinus venosus. In rare occasions, it is large and redundant and it may interfere with catheters and devices used in cardiac catheterization. METHODS: We have developed a new technique to control the EV in order to avoid interferences with the device for closure of atrial septal defects and PFO's. This technique is called "pull-push" technique and consists in pulling down on the inferior vena cava the redundant EV by using a 6 Fr pigtail catheter while a second operator pushes the right atrial disc out of the long sheath. RESULTS: Here, we report on two patients with a patent foramen ovale, in whom the EV prevented the right atrial disc of an Amplatzer PFO occluder to be completely flat against the interatrial septum. Finally, we used this technique in one more patient to avoid any interference of a very redundant EV during placement of a Starflex device. CONCLUSIONS: In conclusion. the so called "pull-push" technique is an alternative and easy technique to control the EV in order to avoid interferences with the device for closure of atrial septal defects and PFO's

Adult↗

PubMed2002

Intersensory redundancy facilitates discrimination of tempo in 3-month-old infants.

L. Bahrick and R. Lickliter (2000) proposed an intersensory redundancy hypothesis that states that information presented redundantly and in temporal synchrony across two or more sensory modalities selectively recruits infant attention and facilitates perceptual learning more effectively than does the same information presented unimodally. In support of this view, they found that 5-month-old infants were able to differentiate between two complex rhythms when they were presented bimodally, but not unimodally. The present study extended our test of the intersensory redundancy hypothesis to younger infants and to a different amodal property. Three-month-olds' sensitivity to the amodal property of tempo was investigated. Results replicated and extended those of Bahrick and Lickliter, demonstrating that infants could discriminate a change in tempo following bimodal, but not unimodal, habituation. It appears that when infants are first learning to differentiate an amodal stimulus property, discrimination is facilitated by intersensory redundancy and attenuated under conditions of unimodal stimulation.

Acoustic Stimulation↗

PubMed1999

Redundant enhancers mediate transcriptional repression of AGAMOUS by APETALA2.

The floral homeotic gene AGAMOUS specifies stamen and carpel fate in the central whorls of Arabidopsis flowers. Transcription of AGAMOUS RNA is restricted to the center of developing flowers by several, partially redundant negative regulators, one of which is the homeotic gene APETALA2. We have identified regulatory elements that mediate transcriptional repression of AGAMOUS by APETALA2 and found that several redundant elements respond independently to loss of APETALA2 activity. Thus, redundancy at the level of cis-regulatory sequences is independent of redundancy at the level of trans-regulators. We have also found that only the early, but not the late, effects of APETALA2 on AGAMOUS require the meristem-identity protein LEAFY, a positive regulator of AGAMOUS.

AGAMOUS Protein, Arabidopsis↗

PubMed1999

Evolutionary preservation of redundant duplicated genes.

Gene duplication events produce both perfect and imperfect copies of genes. Perfect copies are said to be functionally redundant when knockout of one gene produces no 'scoreable', phenotypic effects. Preserving identical, duplicate copies of genes is problematic as all copies are prone to accumulate neutral mutations as pseudogenes, or more rarely, evolve into new genes with novel functions. We summarise theoretical treatments for the invasion and subsequent evolutionary modification of functionally redundant genes. We then consider the preservation of functionally identical copies of a gene over evolutionary time. We present several models for conserving redundancy: asymmetric mutation, asymmetric efficacy, pleiotropy, developmental buffering, allelic competition and regulatory asymmetries. In all cases, some form of symmetry breaking is required to maintain functional redundancy indefinitely.

Animals↗

PubMed1994

The effects of location cuing on redundant-target processing.

The present study is concerned with the redundany gain: the observation that subjects respond faster to simultaneously presented redundant targets than to single targets. This finding is usually interpreted as evidence for parallel, self-terminating, unlimited-capacity processing. Alternatively, it has been claimed that the reaction-time advantage with redundant targets is simply due to spatial uncertainty under single-target conditions. The present study tested this hypothesis. In Experiment 1, subjects responded when one, two, or three letters E were presented, and refrained from responding when one, two, or three letters F were presented. In half of the trials, location uncertainty was eliminated by presentation of a line segment at one the locations of the subsequently appearing target letters. The results reject the alternative spatial-uncertainty explanation: even when the location of the impending target is cued in advance, there is no attenuation of the redundancy gain. Experiment 2 served as a control experiment and showed a clear redundancy gain, even in conditions in which it was ensured that, before display onset, attention was directed to a location of one of the impending targets.

Adolescent↗

PubMed1978

Redundant nerve roots of the cauda equina. A report of five cases.

Five personally examined cases of redundant nerve roots of the cauda equina are added to the 13 hitherto on record. Except for segmental neurological deficits, intermittent claudication-like symptoms of the cauda equina dominated the histories of four of our five cases. The diagnosis was confirmed at surgical exploration, which included laminal and dural decompression. At follow-up (two months--three years) the neurological deficit, or the intermittent claudication, or both, had improved in all our patients. The pathogenesis of root redundancy is obscure. It seems that the symptoms arise through the action of at least two factors viz compression of the spinal content and the existence of one or more redundant roots. Wider use of diagnostic aids and surgical exploration would probably show that redundant roots are more common than hitherto supposed.

Aged↗

PubMed2000

Redundant-signals effects on reaction time, response force, and movement-related potentials in Parkinson's disease.

Studies using transcranial magnetic stimulation have established that patients with Parkinson's disease have increased motor cortex excitability. Relying on current evidence that the redundant-signals effect has its source in the motor system, we investigated whether, as a result of cortical hyperexcitability, Parkinson's disease patients demonstrate an enhancement of this effect. Eight patients with moderately severe Parkinson's disease and nine healthy control subjects participated in a task requiring simple manual responses to visual, auditory, and combined auditory-visual signals. During the task, motor cortex activation was recorded by means of movement-related EEG potentials, while responses were measured via isometric force recordings. The movement-related potentials and the force measures both yielded support for the view that the redundant-signals effect is partially caused in the motor system. However, the facilitatory effect of bimodal as compared to unimodal stimulation (i.e. the redundant-signals effect) was of the same size in Parkinson's disease patients and control subjects, as expressed in latency measures of the movement-related potentials and the force signals. We conclude that the redundant-signals effect is not enhanced in Parkinson's disease and that the mechanisms underlying this effect are probably not influenced by the increased motor cortex excitability found in this disease.

Acoustic Stimulation↗

PubMed1999

ENVIRONMENTAL AUDITING: Measuring Redundancy in Data from Pollution Impact Studies.

/ Time and money could be saved and better invested on environmental monitoring and assessment programs if redundant elements in biological communities were identified. Either aggregation of species into higher taxonomic groupings or selection of indicator taxa are known procedures to eliminate redundancy in large faunal data sets. One further step, the analysis of data without reference to a taxonomic scale, is proposed here. A nondestructive method to just count burrows on sediment surfaces proved adequately suitable to relate faunal responses to water dissolved-oxygen deficiencies along a severely polluted estuary. Consequently, not only taxonomic activities but also the classical destructive approaches separating biota from sediments could be deemed redundant when applied to this case study. Finally, we obtained an extensive benchmark of the situation before the impact is mitigated through the implementation of a sewerage plan promoted by the local water authority. This will serve to: (1) measure the potential recovery of defaunated sediments and (2) evaluate the efficacy of the vast engineering civil work in abating pollution in the near future.KEY WORDS: Redundancy; Faunal surveys; Burrow counts; Hypoxia; Cost effectivenesshttp://link.springer-ny.com/link/service/journals/00267/bibs/24n3p415.html

Journal Article↗

PubMed1987

The effect of redundant cues on comprehension of spoken messages by aphasic adults.

Aphasic adults with severe auditory comprehension impairment responded to redundant and nonredundant spoken and/or gestured messages by pointing to pictures. Messages of two types (pantomime and emblem) were presented under four conditions (spoken message alone, spoken message repeated, gestured message alone, and spoken message plus redundant gesture). Though spoken messages repeated and spoken messages with gestures were comprehended significantly more often than gestures alone, neither of these stimulus conditions was reliably superior to spoken messages alone. This finding casts doubt on the clinical strategy of supplementing spoken messages with redundant gestures when auditory comprehension is severely impaired, and raises questions about the ability of severely aphasic individuals to utilize semantically redundant message content. Pantomimes were consistently comprehended more frequently than emblems, regardless of stimulus condition. This finding was attributed to a depictability factor: the pictures associated with pantomimes were relatively direct representations of item content, while those associated with emblems were necessarily less direct representations. For this group of subjects, whose range of comprehension deficit was deliberately restricted, neither auditory nor reading comprehension at the single-word level was found to correlate with comprehension of symbolic gestures.

Aged↗

PubMed1977

Avian myeloblastosis virus RNA is terminally redundant: implications for the mechanism of retrovirus replication.

We have determined the terminal heteropolymeric sequences of AMV RNA by the following procedures: first, RNA sequence determination on the 5' terminal and the poly(A)-linked 3' terminal T1 oligonucleotides, and second, analysis by the Maxam and Gilbert (1977) method of AMV strong stop DNA and of DNA complementary to the poly(A)-linked T1 oligonucleotide, synthesized with reverse transcriptase and (pdT)13 as primer. The structure deduced for the 5' terminal region is (5')7mGpppGmCCAUUCUACCUCUCACCACAUUGGUGUGCACCUGGGUUGAUGGCCGGACCGUCGAUUCCCUGACGACUACGAGCACCUGCAUGAAGCAGAAGGCUUCAU... Two distinct 3' terminal sequences were deduced: GCCAUUCUACCUCUCAAA...AOH and GCCAUUCUACCUCUCACCAAA...AOH. The two termini, differing by a C-C-A sequence, may reflect genetic heterogeneity of the AMV stock or, more probably, may be generated at or after RNA transcription. These results demonstrate a terminal redundancy of the hetero polymeric sequence of 16 and 19 nucleotides, respectively. The terminal redundancy allows for mechanisms which involve transfer of the DNA segment synthesized on the 5' terminal redundant sequence to the 3' terminal redundant sequence.

Alpharetrovirus↗