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M Faust

Publications and source records attributed to M Faust.

At least 73 records · Page 4Linked to original sources
PubMed1995

Linguistic processes in the two cerebral hemispheres: implications for modularity vs interactionism.

Three experiments are reported on lexical decision to target stimuli presented to the right or left visual field (RVF, LVF) following a variety of priming stimuli, words, incomplete sentences, and scrambled sentences. Lexical decision performance is always superior for stimuli presented to the RVF. Primes always facilitate the discrimination of words from nonword target stimuli presented to either visual field. However, when the prime is a sentence which is completed syntactically and semantically by a target word (normal, congruent sentence), the facilitation for RVF presented targets is significantly greater than for LVF targets. When the prime is either: (1) a single word, (2) a nonstructured (scrambled) sentence, or (3) a noncongruent-related sentence, the difference in facilitation between RVF and LVF presented targets is much smaller. These data are discussed with respect to (1) the nature of priming by sentences versus words, (2) language processing by the two hemispheres, and (3) modularity versus interactionism in language processing.

Adult↗
PubMed1995

Converging evidence for domain-specific slowing from multiple nonlexical tasks and multiple analytic methods.

Older and young adults were tested on eight nonlexical tasks that overlapped extensively in complexity: disjunctive choice reaction time, line-length discrimination, letter classification, shape classification, mental rotation, visual search, abstract matching, and mental paper-folding. Performance on the first seven tasks was associated with equivalently low error rates in both groups, making it possible to directly compare their response times (RTs) on these tasks. Consistent with domain-specific slowing, the relationship between the RTs of the older adults and the RTs of the young adults was well described by a task-independent mathematical (Brinley) function. Evidence from this analysis and from analyses based on task-specific information-processing models leads to similar conclusions and provides converging support for general cognitive slowing in the nonlexical domain.

Adult↗
PubMed1994

Genome analysis of the moss Physcomitrella patens (Hedw.) B.S.G.

A wild-type (WT) strain of the moss Physcomitrella patens (Hedw.) B.S.G., two mutants derived from it (PC22 and P24), and a somatic hybrid, PC22(+)P24, were analysed. Staining of metaphases revealed 54 +/- 2 chromosomes in the somatic hybrid and 27 chromosomes in the wild type and the two mutants. Using flow cytometry (FCM), DNA contents were calculated to be 0.6 pg (WT, PC22), 1.2 pg (P24), and 1.6 pg (PC22(+)P24) per nucleus, respectively. Southern hybridization provided evidence for at least one family of highly repetitive DNA and, furthermore, revealed different amounts of repetitive DNA in the four genotypes. However, these sequences cannot account for the 100% increase in the nuclear DNA amount in mutant P24, relative to wild type. In FCM analyses every moss genotype generated just one single peak of fluorescence, indicating an arrest in the cell cycle during the daytime. Thermal denaturation of wild-type DNA revealed a G+C content of 34.6% for total DNA and 38.6% for plastid DNA. A cDNA library of 1.2 x 10(6) independent clones was established, from which sequences homologous to cab and rbcS, respectively, were isolated. These genes show significant homologies to those of higher plants, and, likewise, comprise multigene families. No restriction fragment length polymorphisms could be detected between the four moss genotypes using these cDNA probes.

Base Composition↗
PubMed1993

Hemisphericity and top-down processing of language.

This study investigated the impact of contextual prompts (priming words and sentences) on the classical finding of superior performance with right visual field stimulation in a lexical decision task. Subjects were presented with prompts of varying lengths (one, three, or six words). The prompts were followed by a target stimulus (word/nonword) to the right or the left visual field. Subjects were required to respond whether the target was a word or a nonword. The major purpose of the study was to determine the extent of right visual field (RVF) superiority, reflecting left hemisphere superiority, in language processing when target stimuli are preceded by semantically meaningful prompts. The results showed that increasing the number of priming words congruent with the target (creating a meaningful context) increased the advantage of the RVF over the left visual field presentation in lexical decision. Thus, even with an available strategy provided by congruent priming stimuli, RVF superiority in lexical decision is retained and even increased.

Adult↗
PubMed1993

Hemispheric specialization or reading habits: evidence from lexical decision research with Hebrew words and sentences.

This paper reports the results of a lexical decision-visual hemifield protocol using Hebrew words and nonwords. The lexical decision task was combined with sentence priming to examine the impact of hemispheric specialization and sentence length. The data are relevant to the Kirsner and Schwartz (1986) hypothesis that reading habits can explain the oft-reported right visual field (RVF) superiority in linguistic tasks. Both the target stimuli and the sentence primes were in Hebrew and 26 male right-handed native Hebrew speakers served as subjects. Hebrew is written and read from right to left. Therefore, according to the favorable foveal viewing explanation (Kirsner & Schwartz, 1986), there should have been no RVF superiority. The results indicated, however, highly significant RVF superiority. Furthermore, priming sentences, written in Hebrew, should direct the attention of the subject to the left visual field in expectation of the appearance of a target word. Nevertheless, the RVF superiority was even more significant when target stimuli were preceded by priming sentences. Both results indicated that reading habits and directed reading attention cannot explain RVF superiority in lexical decision.

Adult↗
PubMed1993

The genomic structure of the human UFO receptor.

Using a DNA transfection-tumorigenicity assay we have recently identified the UFO oncogene. It encodes a tyrosine kinase receptor characterized by the juxtaposition of two immunoglobulin-like and two fibronectin type III repeats in its extracellular domain. Here we describe the genomic organization of the human UFO locus. The UFO receptor is encoded by 20 exons that are distributed over a region of 44 kb. Different isoforms of UFO mRNA are generated by alternative splicing of exon 10 and differential usage of two imperfect polyadenylation sites resulting in the presence or absence of 1.5-kb 3' untranslated sequences. Primer extension and S1 nuclease analyses revealed multiple transcriptional initiation sites including a major site 169 bp upstream of the translation start site. The promoter region is GC rich, lacks TATA and CAAT boxes, but contains potential recognition sites for a variety of trans-acting factors, including Sp1, AP-2 and the cyclic AMP response element-binding protein. Proto-UFO and its oncogenic counterpart exhibit identical cDNA and promoter regions sequences. Possible modes of UFO activation are discussed.

Amino Acid Sequence↗
PubMed1993

[Sleep-related respiratory disorders: early detection and follow-up by close patient contact].

Sleep apnoea (SA) ist a challenge to clinical research, since it occurs in up to 10% of the male professionally active population. It is indeed a challenge in respect of diagnosis, clinical aspects and therapy. SA is not only responsible for mental handicaps during daytime caused by disturbed sleep (increased tendency to doze or fall asleep, proneness to accidents), it will also enhance morbidity and mortality in aspect of cardiopulmonary and cardiovascular diseases (hypertension, cardiac insufficiency, disturbances of cardiac rhythm). All kinds of secondary and/or subsequent damage are reversible, provided diagnosis and rigidly introduced and maintained treatment have been performed well in time. SA can be diagnosed, treated and followed up by means of methods that can be flexibly employed outside the hospital, i.e. on an outpatient basis, such as questionnaires, MESAM IV, behavioural counselling, drug therapy). Within the framework of the current three-year project a stepwise concept was developed for diagnosis and treatment that also includes outpatient examination procedures. This system integrates anamnesis, outpatient monitoring, sleep laboratory, therapy and therapy control into a comprehensive feedback system of patient care. The following standardised procedural steps are included in the outpatient part of this system: baseline examination, treatment that can be performed on an outpatient basis, short-term, medium-term and long-term therapy follow-up. If these steps do not yield satisfactory results or if there is a high acute risk, the patient is subjected to in-patient treatment. At present, 683 first examinations and 420 follow-ups have been recorded.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

The murine ufo receptor: molecular cloning, chromosomal localization and in situ expression analysis.

We have cloned the mouse homologue of the ufo oncogene. It encodes a novel tyrosine kinase receptor characterized by a unique extracellular domain containing two immunoglobulin-like and two fibronectin type III repeats. Comparison of the predicted ufo amino acid sequences of mouse and man revealed an overall identity of 87.6%. The ufo locus maps to mouse chromosome 7A3-B1 and thereby extends the known conserved linkage group between mouse chromosome 7 and human chromosome 19. RNA in situ hybridization analysis established the onset of specific ufo expression in the late embryogenesis at day 12.5 post coitum (p.c.) and localized ufo transcription to distinct substructures of a broad spectrum of developing tissues (e.g. subepidermal cells of the skin, mesenchymal cells of the periosteum). In adult animals ufo is expressed in cells forming organ capsules as well as in connective tissue structures. ufo may function as a signal transducer between specific cell types of mesodermal origin.

Amino Acid Sequence↗
PubMed1991

[Sleep-related respiratory disorders: from syndromes to risk factors].

In the past, sleep related breathing disorders (SRBD) have been described rather heterogeneously in terms of complex diseases, syndromes. During the past ten years, the relevant pathogenetic mechanisms of most of the SRBD could be defined, and data concerning their epidemiology were collected. Epidemiology and dangerousness being relevant criteria, the obstructive sleep apnea syndrome must be regarded as the most considerable SRBD. According to ICSD, the prevalence of a manifest obstructive sleep apnea syndrome is estimated at 1% of the entire population at least. Our measurings have shown that more than 10% of the middle-aged (20 to 60 years) male population suffer from 10 and more mixed obstructive apneas per hour of sleep. In this group, also the other pathogenetic factors for the obstructive sleep apnea syndrome, namely hyperventilation and fragmentation of sleep due to central arousal reactions, are found. All these patients snore, and there is a broad transition from primary snoring, which has no effects on the cardiovascular system and the blood gases, via obstructive snoring up to inter-apneic snoring. With the help of today's technical equipment, it is possible to determine the role of subclinical SRBDs in terms of risk factors, e.g. for cardiovascular diseases. We expect a plain contribution to the clearing up of instances of arterial hypertonus, early invalidity, and mortality.

Adult↗
PubMed1990

[Sleep apnea].

Explore the source record for details and available documents.

Humans↗
PubMed1990

Occupational performance of a paced secondary task under conditions of sensory deprivation. I. Heart rate changes in train drivers as a result of monotony.

Twelve experienced train drivers were asked to operate the train function safety circuit (SIFA)--a paced secondary motor task which is expected to guarantee the driver's fitness for service on engines of the German Federal Railway--under laboratory conditions of extreme monotony. In spite of massive decreases in vigilance as shown by theta-activity in the EEG, all subjects were able to operate the device without major errors. A prerequisite for adequate performance is an EEG-defined arousal reaction, which is synchronized with the SIFA cycles. For 7 subjects the time-related cross-correlation coefficients between SIFA operation, alpha-activity (indicative of alertness), theta-activity (indicative of reduced vigilance), and heart rate were calculated. The central-nervous arousal found in the EEG corresponded to distinct increases in heart rate. The moments of SIFA operation after phases of light sleep correlated significantly and positively with increases in heart rate. These increases constituted a physiological overcompensation as far as the physical readiness was concerned which reached its peak after the task had been performed satisfactorily, constituting additional and superfluous occupational stress. The results of this study indicate clearly that monotony stress is not a result of occupational monotony itself, but the result of the physiological effort which is required in order to regain a level of alterness which allows adequate performance under monotonous conditions.

Electroencephalography↗
PubMed1990

Occupational performance of a paced secondary task under conditions of sensory deprivation. II. The influence of professional training.

Twelve truck drivers operated the train function safety circuit (SIFA), a paced secondary task used as a job monitor on German railways engines, under laboratory conditions of extreme monotony, in a comparison with 12 train drivers who were well acquainted with SIFA. Alertness was determined by means of EEG evaluations. Heart rate was monitored as the parameter for physical load, and the precoded SIFA tasks as the active response parameter. In spite of significantly more frequent and more distinct decreases in alterness, the SIFA-trained subjects (TS) performed better. Nine out of 12 TS reached the stage of light sleep at least once during the experimental run, as compared to 4 out of 12 untrained subjects (US). Nevertheless, the ratio acoustic warnings/occurrence of light sleep was significantly lower in TS (P less than 0.01), and there were three operational errors (equivalent to emergency braking) in US. Whereas US received fewer acoustic warnings in the stages of slightly reduced altertness, this trend was reversed as soon as low frequency theta-activity appeared in the EEG. A time-related calculation of the cross-correlation coefficients between SIFA operation, alpha-activity, theta-EEG-activity, and heart rate showed that timing of SIFA operation interrupting phases of light sleep correlated significantly and positively with increases in heart rate. The results suggest that a mechanism of rhythmic central nervous arousal interrupting phases of decreased alertness/drowsiness can be learned, whereas the physiological consequences of the effort to prevent the deterioration of performance under conditions of monotony are not reduced by professional adaptation.

Automobile Driving↗
PubMed1990

Evaluation of the isobologram method for the assessment of mixtures of chemicals. Combination effect studies with pesticides in algal biotests.

The aim of this paper is an evaluation of isobolograms, a method proposed for the assessment of combined effects of chemicals. In order to examine potentials and shortcomings of this approach for ecotoxicological purposes, algal biotests with selected pesticidal compounds were performed. Additivity, as defined by the model, is demonstrated for the combination of atrazine and metribuzin for different combination ratios, response levels, and parameters. Subadditivity is shown for amitrole and glufosinate-ammonium. The results and inherent biometrical features are discussed in terms of criteria considered suitable for comparative evaluation of biometrical models for the assessment of mixtures of chemicals.

Aminobutyrates↗