bluuebunny/crossref_metadata_2025_split huggingface dataset:
Duroplastische Formmassen für Gleitlager
Authors: Haase I. , Franke R. , Schimke M. 
Published: December 2004

AbstractTribologische Untersuchungen an duroplastischen Formmassen zeigten, daß diese Werkstoffe in Abhängigkeit von den verwendeten Füllstoffen und/oder von tribologischen Additiven für den Einsatz unter geschmierten Gleitreibungsbedingungen geeignet sind. Hochgraphithaltige Formmassen weisen auch unter Trockenreibungsbedingungen einen ausreichenden Verschleißwiderstand auf, wenn die Pressungen nicht zu hoch gewählt werden.
Mikrostruktur und Anlaßverhalten aufgedampfter bzw. thermisch gespritzter ZrO2‐Schichten auf metallischen Substraten
Authors: Wehner B. I. , Blennemann K. P. , Babiak Z. , Selvadurai‐Laßl U. , Köster U. 
Published: December 2004

AbstractDurch ihren Einsatz in Gasturbinen sind plasmagespritzte Wärmedämmschichten aus teilstabilisierten Zirkoniumdioxid auf metallischen Substraten ein Beispiel für einen in der Praxis eingesetzten Schichtverbundwerkstoff aus Keramik und Metall. Die damit verbundenen Probleme vor allem im Bereich der Grenzflächenhaftung sind immer noch teilweise unverstanden [1,2,3]. In der vorliegenden Arbeit werden verschiedene systeme elektronenmikroskopisch untersucht, bei denen eine keramische ZrO2‐Schicht auf ein metallisches Substrat aufgedampft bzw. thermisch gespritzt worden ist. Im Vordergrund steht die Gefügeanalyse des Verbundwerkstoffes, wobei der Versuch unternommen wird, mit Hilfe der durch TEM‐Querschliffe möglichen Zielpräparation auch die Grenzflächenmorphologie aufzuklären.
Mikromechanische Bewertung von mineralgefüllten Kunststoffen mit Hilfe dielektrischer Relaxationsspektroskopie und Mechano‐Dielektrometrie
Authors: Schreyer G. W. , Bartnig K. , Sander M. 
Published: December 2004

AbstractDieser Beitrag beschreibt die Möglichkeit der quantitativen Bestimmung von Rißbildungsgrenzen polarer, mineralmodifizierter Kunststoffe durch Kombination von mechanischem Experiment und dielektrischer Meßtechnik. Durch Ermittlung der dielektrischen Kennfunktion tan δ = f (ϵmech) während des Zugversuches nach DIN 53455 läßt sich ein Zusammenhang zwischen beanspruchungsbedingten Strukturänderungen und Versagensgrenzen herstellen. Für das dielektrische Relaxationsverhalten der Verbundwerkstoffe, in Verbindung mit den mechanisch induzierten Werkstoffschädigungen, wird eine mikromechanisch begründete Interpretation vorgeschlagen.
Die elektrische Emission beim Versagen von Faserverbundwerkstoffen und ihren Komponenten
Authors: Sklarczyk C. , Winkler S. , Thielicke B. 
Published: December 2004

AbstractVerformungen und Schädigungen können die Ursache von elektrischen Ladungsverschiebungen in Faserverbundwerkstoffen (FVW) sein, welche zu Änderungen des äußeren elektrischen Feldes führen. Diese können mit geeigneten Sonden berührungslos beobachtet und aufgezeichnet werden. Die Analyse dieser elektrische Emission (EE) genannten Signale kann individuell oder statistisch geschehen, wobei im letzteren Falle Schallemissionsgeräte verwendet werden können. Das Brechen von Carbon ‐oder Glasfasern erzeugt EE‐Signale großer Amplitude, das Brechen des Polykarbonat‐Matrixmaterials dagegen geringere. Das Zerreißen der Verbundwerkstoffe im Zugversuch ist zwar von größeren Signalen begleitet als das des reinen Matrixmaterials; jedoch erreichen diese Signale nicht die Amplituden des Fasermaterials. Die Analyse der Signalformen gestattet Rückschlüsse auf den Ablauf der elementaren Bruchprozesse und deren Dynamik. Diese Arbeit hat gezeigt, daß die elektrische Emission neben anderen Methoden – wie der Schallemission – ein brauchbares Werkzeug zur Beobachtung des Eintritts von Schädigungen in Verbundwerkstoffen ist. Da diese Methode kontaktlos arbeitet und keine Probenvorbereitung erfordert, ist sie nicht nur kostengünstig. Sie kann möglicherweise auch vorteilhaft über Laboratoriumsanwendungen hinaus benutzt werden.
Entwicklungen von verschleiß‐und korrosionsbeständigen Oberflächensystemen. Development of wear and corrosion resistant surface syatems
Authors: Ahn H. , Pfohl C. , Wöhle J. , Gebauer A. , Biemer S. , Bulak A. , Menthe E. , Cabeo E. Rodriguez , Stucky T. , Gebauer A. 
Published: December 2004

AbstractIn dieser Arbeit werden zwei Verfahren zur Realisierung verschleiß‐und korrosionsbeständiger Oberflächensysteme beschrieben: Plasmadiffusionsbehandlung (PDT) und Plasmagestütztes CVD (PACVD). Neben den Plasmanitrierverfahren werden auch Plasmanitrocarburieren und Plasmanborieren von unterschiedlichen Substratwerkstoffen behandelt. Die Fortschirtte beim PACVD und die Entwicklung zu den Niedertemperaturbeschichtungsverfahren werden erläutert und Anwendungen dieser Techniken in der Industrie beispielhaft erwähnt.
Einfaches partielles Aufkohlen für industrielle Anwendungen. Simple Partial Carburizing for Industrial Applications
Authors: Schnatbaum F. 
Published: December 2004

AbstractDas partielle Aufkohlen von Bauteilen mit Hilfe konventioneller Methoden ist ein relativ aufwendiger und kostenintensiver Prozeß. Als Möglichkeiten stehen derzeit im wesentlichen 2 Methoden zur Verfügung:das Abdecken der fraglichen Bereiche mit Pasten vor dem Aufkohlen oderdas Fertigen mit Übermaß und anschließendem Abschleifen aufgekohlter Bereiche.Anhand von Beispielen wird gezeigt, daß das Aufkohlen im Plasma durch einfaches Abdecken von Bauteilbereichen mit Masken oder Blechen erreicht wird und damit eine Möglichkeit gegeben ist, Bauteile einfach und kostengünstig partiell aufzukohlen.
Witterungsbeständige Kunststoffe und Textilien im Automobilbau – Korrelation zwischen Frei‐und Gerätrebewitterung – Teil I
Authors: Lampe Thomas , Schwarzer Peter , Ackermann Matthias , Kaiser Hans‐Georg , Roggenbach W. 
Published: December 2004

AbstractKunststoffe und Textilien sind im Automobilbau zum Teil extremen Witterungseinflüssen ausgesetzt. Diese bewirken eine Alterung der Materialien und Bauteile, die z. B. in Form von Rissen, Farbänderungen oder Verformungen sichtbar werden kann.Im ersten Teil dieses Beitrages werden die für die Alterung von Polymerwerkstoffen wesentlichen Klimagrößen und die hieraus resultierenden Beanspruchungen von Fahrzeugbauteilen beschrieben.Im zweiten Teil werden Methoden zur Prüfung der Witterungsbeständigkeit vorgestellt, zunächst die Freibewitterung, bei der die Prüfobjekte der natürlichen Witterung ausgesetzt sind, danach einige Kurzzeitprüfmethoden, die auf künstlich in Geräten erzeugten Klimata basieren. Anschließend wird die Korrelation zwischen Frei‐und Gerätebewitterung anhand ausgewählter Beispiele dargestellt.
Schädigungsentwicklung der Legierung IN 738 LC bei Hochtemperatur‐LCF‐Beanspruchung
Authors: Frenz Holger , Klingelhöffer Hellmuth 
Published: December 2004

AbstractIn einer Serie von unterbrochenen Low‐Cycle‐Fatigue Versuchen wurden diese Schädigungsentwicklungen der Legierung IN 738 LC bei 850°C untersucht. Intensive Nachuntersuchungen der Probenoberflächen mittels REM lieferten Aussagen zu der statischen Entwicklung von Rißentstehung und Rißwachstum. Anrisse an oxidierten Korngrenzen entstehen während des gesamten Experimentes. Dem Zusammenwachsen kleiner Risse zu einem Makroriß kommt einer dominierende Rolle bis zum Versagen der Proben zu.
Huntington's disease in venezuela: 7 years of follow‐up on symptomatic and asymptomatic individuals
Authors: Penney John B. , Young Anne B. , Shoulson Ira , Starosta‐Rubenstein Simon , Snodgrass S. Robert , Sanchez‐Ramos Juan , Ramos‐Arroyo Maria , Gomez Fidela , Penchaszadeh Graciela , Alvir Jose , Esteves Jesus , DeQuiroz Iris , Marsol Nelson , Moreno Humberto , Conneally P. Michael , Bonilla Ernesto , Wexler Nancy S. 
Published: December 2004

AbstractPersons symptomatic and at risk for Huntington's disease (HD) from a large extended family in the state of Zulia, Venezuela, have been followed prospectively for 7 years. Between 1981 and 1988, 593 people were examined, of whom 128 had symptomatic HD and 171 persons at risk had examination abnormalities that were insufficient to meet criteria for diagnosis. The remaining 294 had normal examinations. Abnormalities of saccadic eye movement and slowness of rapid alternating movements were the most common abnormalities found in at‐risk individuals. Thirty persons who did not meet criteria for diagnosis at their first examination have subsequently been diagnosed with symptomatic HD. Their average age at diagnosis was 33.5 ± 8.3 (SD) years. The likelihood of developing symptomatic HD within 3 years was 3% for those persons with normal first examinations, 23% for those with mildly abnormal first examinations, and 60% for those with highly abnormal first examinations. The rate of disease progression in early symptomatic cases were 1.4 ± 0.1 (SEM) points per year on the Shoulson‐Fahn functional capacity scale. Paternal or maternal inheritance did not appear to affect the rate of progression in this group of individuals. The data suggest that there is not a discrete age of onset but rather a prolonged period of time during which symptoms unfold.
Movement disorders in mitochondrial myopathies. A study of nine cases with two autopsy studies
Authors: Truong Daniel Dung , Harding A. E. , Scaravilli F. , Smith S. J. M. , Morgan‐Hughes J. A. , Marsden C. D. 
Published: December 2004

AbstractOf 85 consecutive patients with mitochondrial myopathy, 29 had clinically significant central nervous system involvement. Nine of these had movement disorders that included dystonia, chorea, parkinsonism, and myoclonus. Autopsy studies of one patient with ataxia, dementia, and parkinsonism followed by dystonia showed the features of olivopontocerebellar atrophy with additional degenerative changes in the basal ganglia. Postmortem in a further case with myoclonus, deafness, muscle weakness, retinopathy, and ataxia showed symmetrical mineralisation of the striatopallidodentatal system.
Primary writing tremor. A form of focal dystonia?
Authors: Elble Rodger J. , Moody Charles , Higgins Constance 
Published: December 2004

AbstractFive patients exhibited severe tremor in the upper extremity, primarily when attempting to write or draw. Electromyography was performed to determine the patterns of muscle activity that were responsible for this tremor. Tremor was measured with an accelerometer and with a digitizing tablet. Two patients had postural tremor that was indistinguishable from mild, high‐frequency essential tremor. All patients exhibited a severe 5–7‐Hz tremor during the acts of writing and drawing. Muscles throughout the affected extremity exhibited rhythmic 5–7‐Hz bursts of motor unit discharge, and the average level of motor unit activity was tonically increased in antagonistic muscles. This abnormal coactivation of antagonistic muscles produced subtle dystonic posturing of the affected limb that was overshadowed by severe tremor. Electromyography was useful in confirming the coexistence of tremor and dystonia in our patients. The nonspecificity of dystonia and postural tremor must be considered when discussing the nosology and pathophysiology of primary writing tremor.
Psychogenic dyskinesias in patients with organic movement disorders
Authors: Ranawaya Ranjit , Riley David , Lang Anthony 
Published: December 2004

AbstractThe association of psychogenic neurological features with organic neurological disease is commonly acknowledged. However, the occurrence of psychogenic dyskinesias in patients with underlying organic movement disorders is not well recognized. Six cases of psychogenic dyskinesias complicating preexisting organic movement disorders are described. This possibility must be carefully considered and excluded before an unusual movement disorder can be considered entirely psychogenic.
Dentatorubro‐pallidoluysian atrophy of the myoclonus epilepsy type with posterior column degeneration
Authors: Pfeiffer Ronald F. , McComb Rodney D. 
Published: December 2004

AbstractDentatorubro‐pallidoluysian atrophy (DRPLA) has a variable clinical presentation but the pathology is routinely confined to cerebellifugal and pallidofugal systems. We present a case of DRPLA of the myoclonus epilepsy type in which prominent posterior column degeneration was added to the pathological picture. This case illustrates the concept that the neurodegenerative diseases can be a continuum of both clinical and pathological presentations.
Gaze‐evoked involuntary movement
Authors: Sethi K. D. , Hess D. C. , Harbour R. C. , Holmes G. L. 
Published: December 2004

AbstractVoluntary gaze may evoke a number of neurological phenomena such as vertigo, tinnitus, blepharoclonus, eyelid nystagmus, “facial nystagmus,” involuntary laughter, and seizures. We report two patients in whom eccentric gaze evoked facial twitching and arm movement. Electroencephalograms remained unchanged during these movements. The pathogenesis of these movements is unclear but may involve ephaptic transmission.
Diffuse lewy body disease with dementia and oculomotor dysfunction
Authors: Lewis A. J. , Gawel M. J. 
Published: December 2004

AbstractThe case is presented of an elderly patient who had dementia, axial rigidity, and bradykinesia with limitation of horizontal and vertical gaze. Pathological examination disclosed Lewy and Lewy‐like bodies in the substantia nigra, locus ceruleus, and neocortex, leading to a final diagnosis of diffuse Lewy body disease. Similar inclusions were found in areas of the pons and midbrain believed to be associated with gaze control. Moderate numbers of neuritic plaques, but no neurofibrillary tangles, were present in limbic cortex and neocortex. Review of the literature has not shown previous association of diffuse Lewy body disease with both horizontal and vertical gaze anomalies.
Mood changes and “on‐off” phenomena in Parkinson's disease
Authors: Menza Matthew A. , Sage Jacob , Marshall Eric , Cody Ronald , Duvoisin Roger 
Published: December 2004

AbstractTen patients with idiopathic Parkinson's disease and motor fluctuations were rated for mood changes during discrete “off,” “on,” and “on with dyskinesia” periods. The Profile of Mood States and visual analogue scales were used. Significant changes in mood and anxiety were found to parallel changes in motor fluctuations. One patient rated his moods as consistently improving from the “off” state to the “on” state and finally to the “on with dyskinesia” state, a finding that is consistent with concomitant central dopaminergic changes. All other patients showed moods that improved significantly from the “off” state to the “on” state but then worsened significantly in the “on with dyskinesia” state, a finding that is consistent with the fact that patients feel worse when impaired by dyskinesias. It is suggested that these results argue for multiple etiologies of depression in Parkinson's disease. The literature on dopamine and depression in Parkinson's disease is briefly reviewed and the opportunity provided by “on‐off” phenomena to study the effect of dopamine on mood changes is discussed.
A pilot study of risk factors for dementia in Parkinson's disease
Authors: Marder Karen , Flood Pamela , Cote Lucien , Mayeux Richard 
Published: December 2004

AbstractTo determine whether the risk factors for dementia in idiopathic Parkinson's disease (IPD) are similar to the risk factors for Alzheimer's disease, we conducted a case‐control study of potential risk factors. A structured interview as was administered to surrogates of 17 demented subjects with IPD and 54 nondemented subjects. Two factors emerged as possible risks for dementia. Demented patients were older than nondemented patients, although the duration of symptoms was similar. A family history of dementia was present in 30% of the demented group and 5.6% of the nondemented group. Dementia was most often reported among siblings. No difference was seen in toxic and occupational exposure, personal habits, or medical or surgical illnesses. We conclude that dementia in IPD shares some common risk factors with Alzheimer's disease. Efforts to assess the contribution of genetic susceptibility or shared environmental influences may clarify the relationship between these two diseases.
Neuroleptic malignant syndrome treated with subcutaneous lisuride infusion
Authors: Rodriguez M. E. , Luquin M. R. , Lera G. , Delgado G. , Salazar J. M. , Obeso José A. 
Published: December 2004

AbstractA schizophrenic patient developed a characteristic clinical picture of neuroleptic malignant syndrome (NMS) while admitted to the hospital during an exacerbation of his psychiatric symptoms. Oral treatment of the NMS with bromocriptine (7.5 mg/day) or levodopa/carbidopa (125/12.5 mg) provoked intense vomiting in spite of domperidone (60 mg/day), which led to their discontinuation. In view of the deterioration of the symptoms, treatment was begun with lisuride (1–2 mg/24 h) subcutaneously. An obvious improvement was shown in 24 h, but levodopa/carbidopa (125/12.5 mg t.d.s. orally) had to be added later to achieve complete resolution of the NMS. During the recovery phase, while being treated with subcutaneous lisuride infusion and levodopa (p.o.), the patient presented with confusion, agitation, and hallucination. Lisuride infusion was stopped and levodopa was continued until complete resolution of the NMS. This case indicates that parenteral administration of lisuride or other dopamine agents such as levodopa (i.v.) or apomorphine (s.c.) may be considered an effective and practical way of treating NMS, particularly when the patient's condition makes it difficult or impossible to use other dopaminergic drugs by the oral route.
Hypoxic‐ischemic damage of the basal ganglia case reports and a review of the literature
Authors: Hawker Kathleen , Lang Anthony E. 
Published: December 2004

AbstractThree cases of movement disorders secondary to hypoxic‐ischemic encephalopathy are reported. Despite similarities among the clinical events, the neurological syndromes produced were dissimilar. Cerebral hypoxiaischemia typically produces lesions of the globus pallidus that may result in an akinetic rigid syndrome. Due to its unique blood supply, vascular insufficiency is found to be a major factor. Lesions in the putamen also occur, and these tend to be associated with dystonia. Recent evidence supports a specific neuronal sensitivity in the striatum, possibly due to afferent excitatory amino acid connections. These two components and changes in the levels of neurotransmitters during hypoxia‐ischemia may interact to produce varied clinical outcomes. These factors must also be considered when planning therapeutic interventions.
Clozapine‐responsive tremor in Parkinson's disease
Authors: Friedman J. H. , Lannon M. C. 
Published: December 2004

AbstractClozapine is an atypical neuroleptic medication that is free of parkinsonian side effects and that has been reported to ameliorate the tremor of Parkinson's disease. We report (with videotape illustration) the dramatic improvement of severe yet classic rest tremors in one elderly nonpsychotic patient with Parkinson's disease and significant improvement in four others. We believe that clozapine, in low doses, may be a useful medication for the treatment of rest tremor in Parkinson's disease, even in cases without mental abnormalities.
Paroxysmal kinesigenic dystonic choreoathetosis associated with a thalamic infarct
Authors: Camac Ann , Greene Paul , Khandji Alex 
Published: December 2004

AbstractWe describe a patient with the development of paroxysmal kinesigenic dystonic choreoathetosis (PKDC) after a thalamic infarct. PKDC consists of brief episodes of dystonia or choreoathetosis triggered by movement. PKDC improves with anticonvulsants, and in some cases, with L‐Dopa or anticholinergics. We review PKDC, and relate its salient features to idiopathic and secondary torsion dystonia. We postulate a similar underlying pathophysiology.
Clozapine for psychosis in Parkinson's disease
Authors: Pfeiffer Ronald F. , Kang Jasbir , Graber Benjamin , Hofman Ruth , Wilson James 
Published: December 2004

AbstractThe clinical efficacy of clozapine, an atypical antipsychotic, in treating levodopa‐induced hallucinations was investigated in five patients with Parkinson's disease under open label conditions. Two patients could not tolerate clozapine, even in doses as low as 12.5–25 mg daily, because of extreme sedation. Three patients could tolerate clozapine and experienced improvement or elimination of their hallucinations at doses below 100 mg daily. Despite a significant risk of adverse effects, cautious use of clozapine in low doses may be beneficial for patients with levodopa‐induced psychosis who do not respond to more conservative measures.
A case of senile chorea
Authors: Friedman Joseph H. , Ambler Mary 
Published: December 2004

AbstractSenile chorea, a late‐onset, slowly progressive disorder without mental changes, is a poorly characterized entity. It is often thought to represent late‐onset Huntington's disease in which the chorea precedes the mental changes and the family history is absent due to parental death before symptoms. The following case differs pathologically from Huntington's disease and from previous reports of senile chorea.
Antiparkinsonian activity of a non‐ergot dopamine agonist, CV 205‐502, in patients with fluctuating Parkinson's disease
Authors: Poewe W. , Luef G. , Kleedorfer B. , Emre M. 
Published: December 2004

AbstractSix patients with fluctuating Parkinson's disease received single rising oral doses of the nonergot dopamine agonist CV 205‐502 in an open experimental study. Doses of 0.5 mg produced antiparkinsonian effects of comparable intensity but longer duration than 200 mg of L‐DOPA. CV 205‐502, which combines structural features common to both ergolines and apomorphine, thus revealed interesting antiparkinsonian properties, but nausea and vomiting were dose‐limiting side effects in all patients tested.
Dopaminergic responsiveness to apomorphine after chronic treatment with subcutaneous lisuride infusion in Parkinson's disease
Authors: Vaamonde J. , Luquin M. R. , Obeso J. A. 
Published: December 2004

AbstractThe aim of this study was to assess whether or not continuous infusion of lisuride in combination with intermittent levodopa‐carbidopa administration was associated with tolerance. Intravenous apomorphine was given to four patients before initiation of chronic treatment with subcutaneous lisuride infusion and oral levodopa. The study was repeated under identical conditions after a mean of 18 months of treatment. In no case was the motor response induced by apomorphine infusion reduced as compared to baseline assessment. Choreic dyskinesias accompanying the “on” state were enhanced in all patients. These findings suggest that chronic continuous infusion of a dopamine agonist like lisuride, associated with oral levodopa, is not accompanied by tolerance or down‐regulation of striatal dopaminergic receptors.
Alcohol‐responsive myoclonic dystonia in a large family: Dominant inheritance and phenotypic variation
Authors: Kyllerman M. , Forsgren L. , Sanner G. , Holmgren G. , Wahlström J. , Drugge U. 
Published: December 2004

AbstractAlcohol‐responsive myoclonic dystonia is reported in 26 individuals in a six‐generation family, thus indicating autosomal dominant inheritance. Twenty affected family members aged between 3 and 56 years were examined on one occasion. Myoclonus in arms, shoulder, and neck distribution was seen in 17, with occasional generalized jerks in 14. Leg dystonia/hemidystonia was seen in two infant cases, writer's cramp in seven, torticollis/retrocollis in two, and finger tremor in three. The onset of myoclonus was regularly reported from 2 to 3 years of age, the onset of leg dystonia/hemidystonia from 6 to 18 months of age, writer's cramp from early school age, and neck dystonia from late teenage. The effect of alcohol had been noted in 10 individuals, and seven of them abused alcohol. Once established, the neurological signs did not progress significantly. Leg dystonia resolved in two juvenile members. Two adult members had recovered from myoclonus: one elderly man and one posthemorrhagic spastic hemiplegic man. Extensive family investigation is necessary to clarify the clinical variation of this autosomal dominant disorder of involuntary movements.