bluuebunny/crossref_metadata_2025_split huggingface dataset:
Röntgenographische Untersuchung von Spannungszuständen in Werkstoffen Teil IV. Fortsetzung von Matwiss. und Werkstofftechn. Heft 3/1995, S. 148–160, Heft 4/1995, S. 199–216 und Heft 9/1996, S. 426–437
Authors: Eigenmann B. , Macherauch E. 
Published: December 2004

X‐Ray Investigation of Stress States in MaterialsX‐ray stress analyses of crystalline or partially crystalline materials are based on the determination of elastic lattice strains which are converted to stresses by means of theory of elasticity. The development of the sin2Ψ‐method of X‐ray stress analysis and of diffractometers substituting film chambers during the 1960s initiated an enormous progress in X‐ray stress analysis during the following three decades both in respect of the knowledge of the underlying principles and in respect of the practical application.This report sketches the historical development of X‐ray stress analyses and describes the actual state of the art of this important tool for materials science and engineering. Besides some important elements of X‐ray physics and theory of elasticity, experimental aspects of practical applications are outlined. Standard measuring procedures and special measuring problems are described and hints for practical solutions are given. In particular, examples of destructive and non‐destructive depth profiling of residual stresses of residual stress analyses in thin coatings, in multilayer structures of thin coatings and in chemically graded coatings, of residual stress analyses in presence of textures, of residual and loading stress analyses in heterogeneous materials, in coarse grained, and in single crystalline materials are presented. The methods established up to now are explained and possible future developments are pointed out.
Modellierung des Einflusses von Temperatur und Verformungsgeschwindigkeit auf die Fließspannung von Ck 45 bei Temperaturen T ≲ 0,3 Ts
Authors: Burgahn F. , Schulze V. , Vöhringer O. , Macherauch E. 
Published: December 2004

AbstractAnschließend an die Darstellung der theoretischen Grundlagen der thermisch aktivierten Versetzungsbewegung wird ein Auswerteverfahren vorgestellt, das den Einfluß von Temperatur und Verformungsgeschwindigkeit auf die Fließspannung modellmäßig zu beschreiben erlaubt. Dazu ist es erforderlich, in Zugversuchen Fließspannungswerte und in Geschwindigkeitswechselversuchen thermische Fließspannungssprünge bei verschiedenen Temperaturen und Verformungsgeschwindigkeiten zu messen und die Temperaturabhängigkeit des Elastizitäts‐bzw. Schubmoduls zu kennen. Die Leistungsfähigkeit dieses Verfahrens wird anhand von Versuchsergebnissen gezeigt, die an Proben aus normalisiertem Ck 45 ermittelt wurden. Die konstitutive Gleichung gestattet die zuverlässige Extrapolation der Fließspannungswerte zu Verformungsgeschwindigkeiten bis 10+4 s−1. Der Einfluß der plastischen Dehnung auf die Kenngrößen der Modellgleichung wird diskutiert.
Effect of surfactants on the rate of diffusion‐controlled Cementation of copper from dilute solutions on a stationary zinc disc in stirred vessels
Authors: Zarraa Mahmoud A. 
Published: December 2004

AbstractThe effect of surfactants on the rate of diffusion‐controlled cementation of copper from dilute copper sulphate solutions on a stationary zinc disc in a stirred vessel was studied. Variables investigated were rotational speed of the impeller, concentration and type of surfactants and concentration of copper sulphate solution. These variables were studied for their effect on the mass transfer coefficient of copper cementation. The mass transfer coefficient was found to increase with increasing rotational speed of the impeller and concentration of copper sulphate solution. It was found that surfactants decrease the rate of mass transfer during cementation by an amount ranging from 9.5 to 25° depending on the rotational speed of the impeller and type of surfactant added. Increasing surfactant concentration was found to decrease the mass transfer coefficient. The ability of different surfactants to decrease the mass transfer coefficient increases in the order: CTMAB < SABS < NPPGE. Mass transfer data were correlated, in absence and in presence of surfactants, by the following equations respectively:

Where Sh is Sherwood number, Re is Reynolds number, and Sc is Schmidt number.
Zur Aussagefähigkeit der Almenintensität als Kennwert bei der gezielten Eigenspannungserzeugung durch Kugelstrahlen
Authors: Herzog R. , Zinn W. , Scholtes B. , Wohlfahrt H. 
Published: December 2004

AbstractIn der technischen Praxis werden Kugelstrahlbehandlungen üblicherweise durch die Angabe von Almenintensität, Überdeckung sowie von Art und Härte des Strahlmittels und Strahlgutes beschrieben. Dies ist jedoch im Hinblick auf die erzeugten randnahen Werkstoffeigenschaften nicht in allen Fällen eindeutig und ausreichend. Am Beispiel experimenteller Untersuchungen zum Einfluß der Almenintensität und des Strahlmitteldurchmessers auf die Eigenspannungsausbildung wird diese Problematik dargestellt und anhand energetischer Betrachtungen des Strahlprozesses erläutert und diskutiert.
Gilles de la tourette's syndrome in twins: Clinical and neurochemical data
Authors: Goetz Christopher G. , Tanner Caroline M. 
Published: December 2004

AbstractA pair of identical twins (probability of monozygosity by genetic marking = 99.99%) with Gilles de la Tourette's syndrome (GTS) were studied clinically and neurochemically. The two boys were distinguished within the family by dramatic differences in their behavior and tics. Twin 1 had severe motor tics, loud vocalizations, coprolalia, and school behavior problems, whereas twin 2 was only mildly affected. Neither boy had ever been treated with medication for his tic disorder. Lumbar puncture was performed on each after a night of bed rest. In spite of the marked clinical differences between the two boys, the major indices of dopamine and serotonin turnover in the cerebrospinal fluid were equivalent. Homovanillic acid levels were 65 and 60 ng/ml, respectively, and 5‐hydroxyindoleacetic acid levels were 36 and 39 ng/ml. Observation of these twins suggests that the phenotypic expression of GTS relates to more factors than inheritance. Neurochemical metabolites of dopamine and serotonin did not reflect the comparative clinical severity of GTS in these boys.
Twin studies and the genetics of Parkinson's disease—a reappraisal
Authors: Johnson William G. , Hodge Susan E. , Duvoisin Roger 
Published: December 2004

AbstractParkinson's disease (PD) has long been regarded as having a hereditary component. However, three recent twin studies have been interpreted as excluding any significant genetic component in the etiology of PD. In this article, we reexamine these twin studies and argue that such a conclusion is premature. We review statistical tests of twin concordance rates, including calculation of G, the coefficient of genetic determination. When variation in a trait is due entirely to genetic factors G = 1, and when variation in a trait is due entirely to nongenetic factors G = 0. We conclude that: (a) low monozygotic concordance rates can be compatible with substantial genetic contribution to etiology; (b) the PD twin study data give substantial optimal values of G (up to 0.78) but the very broad 95% confidence limits for G make it impossible for the twin study data to prove or disprove a substantial genetic component to the etiology of PD; and (c) changing clinical concepts of PD have undermined the assumptions underlying the methodology of the PD twin studies. We review three genetic models that are biologically plausible for PD and are compatible with the low twin concordance rates. Finally, we suggest that further family studies, including linkage studies, are needed to resolve this question.
The metabolic anatomy of Parkinson's disease: Complementary [18F]fluorodeoxyglucose and [18F]fluorodopa positron emission tomographic studies
Authors: Eidelberg D. , Moeller J. R. , Dhawan V. , Sidtis J. J. , Ginos J. Z. , Strother S. C. , Cedarbaum J. , Greene P. , Fahn S. , Rottenberg D. A. 
Published: December 2004

AbstractWe studied the metabolic anatomy of typical Parkinson's disease (PD) using [18F]fluorodeoxyglucose (FDG) and [18F]fluorodopa (FDOPA) and positron emission tomography (PET). Fourteen PD patients (mean age 49 years) had FDG/PET scans, of which 11 were scanned with both FDOPA and FDG. After the injection of FDOPA, brain uptake and arterial plasma radioactivity were monitored for 2 h. Striatal FDOPA uptake was analyzed with regard to a two‐compartment model, and target‐to‐background ratios (TBRs) and TBR‐versus‐time slopes were also calculated. Regional patterns of metabolic covariation were extracted from FDG/PET data using the Scaled Subprofile Model (SSM). SSM pattern weights, FDOPA uptake constants (Ki), TBRs, and TBR slopes were correlated with clinical measures for bradykinesia, rigidity, tremor, gait disturbance, left‐right asymmetry, dementia, and overall disease severity. In PD patients, rate constants for FDOPA uptake correlated with individual measures of bradykinesia (p = 0.001) and gait disability (p < 0.05). SSM analysis revealed a distinct pattern of regional metabolic asymmetries, which correlated with motor asymmetries (p < 0.001) and left‐right differences in Ki (p < 0.01). Our data suggest that in PD patients, FDG/PET and FDOPA/PET may provide unique and complementary information about underlying disease processes.
Central motor conduction to hand and leg muscles in Huntington's disease
Authors: Hömberg V. , Lange H. W. 
Published: December 2004

AbstractUsing electromagnetic stimulation of motor cortex and cervical or lumbar roots, central conduction times to the thenar and abductor hallucis muscles bilaterally were determined in a population of 32 patients with definite Huntington's disease (HD) and 14 subjects at risk. The HD patients showed a wide variety of different severity of choreatic movements, disease duration, and total disability. None of the stimulation parameters (latency after cortical stimulation, amplitude, threshold, or central conduction time) revealed statistically significant abnormalities compared with a normal control group as well as between patient subgroups. The data indicate that central motor conduction to upper and lower extremity muscles remains normal in Huntington's disease irrespective of the severity of the disorder.
A controlled trial of piracetam in intellectually impaired patients with Parkinson's disease
Authors: Sano Mary , Stern Yaakov , Marder Karen , Mayeux Richard 
Published: December 2004

AbstractTwenty patients with Parkinson's disease and marked intellectual impairment or dementia participated in a double‐blind placebo controlled trial of the nootropic, piracetam. A standardized neurological examination, a neuropsychological test battery, and a functional scale, The Sickness Impact Profile, were completed for all patients. They were then assigned by blind randomization to drug or placebo conditions receiving 3.2 g of piracetam or an identical amount of placebo for 12 weeks. The dose was increased to 4.8 g for an additional 12 weeks. Neurological, psychological, and functional measures were rated as improved, unchanged, or worsened in comparison to baseline performance. Twenty‐five percent of the patients did not complete the trial for reasons unrelated to the medication. Although there was a significant improvement on one subtest of the functional scale, no significant effects were demonstrated in cognitive or neurological measures.
Evaluation of a modified inverted walking stick as a treatment for Parkinsonian freezing episodes
Authors: Dietz Mark A. , Goetz Christopher G. , Stebbins Glenn T. 
Published: December 2004

AbstractWe evaluated a modified inverted walking stick [visual cue (VC) stick] in Parkinson's disease patients with freezing episodes. Patients underwent baseline trials on a 60‐ft track with four walking conditions: unassisted, with a straight walking stick, with the VC stick, and on the track with parallel lines spaced every 12 in. Patients completed three trials of each condition in a randomized order, with total course time and number of freezes recorded. Patients were given the VC stick to use at home until subjective maximum functional benefit was obtained and were then brought back for a follow‐up objective evaluation. Eight patients completed the study. The straight stick and VC stick worsened patient performance as a group, while the parallel lines significantly improved group performance. However, two of the eight patients showed benefit from the VC stick. Improvement with parallel lines did not predict improvement with the VC stick. On follow‐up trials, the two who initially showed improvement with the VC stick continued to show improvement, while none of the other patients showed additional benefit from a learning effect. We conclude that the VC stick will help a small subpopulation of Parkinson's disease patients with freezing, and this subpopulation can be identified with the initial office visit trial.
Adrenal to caudate transplantation—postmortem study
Authors: Waters C. H. , Itabashi H. H. , Apuzzo M. L. J. , Weiner L. P. 
Published: December 2004

AbstractA patient with Parkinson's disease who had undergone bilateral adrenal to caudate implantation by stereotactic technique came to autopsy. The implantation was shown to have produced minimal trauma and to have been well placed. Minimal surviving adrenal medullary tissue remained in the implanted coil, and no outgrowth of tissue into the striatum occurred.
Sleep disorders and sleep effect in Parkinson's disease
Authors: Factor Stewart A. , McAlarney Terence , Sanchez‐Ramos Juan R. , Weiner William J. 
Published: December 2004

AbstractIt has been suggested that sleep may have a positive effect on morning motor symptoms in Parkinson's disease (PD). We examined this possibility and also looked at common sleep disorders in PD. Seventy‐eight PD patients and 43 normal elderly subjects answered a questionnaire. Of the PD patients, 43.6% reported improved motor symptoms in the morning, 37.2% worse, and 19.2% unchanged compared to the rest of the day. No difference was found between morning‐better and ‐worse groups with respect to age, duration or stage of PD; antiparkinsonian medications utilized, and predominant motor symptoms. However, the morning‐same group had a shorter duration of PD and less severe disease and required fewer dopaminergic medications. Sleep disorders were seen with equal frequency in the morning‐better and ‐worse groups. Our results suggest that sleep does not have a direct effect on morning motor function. Alterations in morning motor symptomatology probably represent a manifestation of motor fluctuations. Sleep fragmentation and spontaneous daytime dozing occurred much more frequently in PD patients than controls. In addition, nocturnal vocalizations and daytime hallucinations occurred only in the PD group.
Mitochondrial DNA analysis in Parkinson's disease
Authors: Schapira A. H. V. , Holt I. J. , Sweeney M. , Harding A. E. , Jenner P. , Marsden C. D. 
Published: December 2004

AbstractThe reduced form of nicotinamide adenine dinucleotide coenzyme Q reductase (complex I) activity has recently been shown to be deficient in the substantia nigra of patients dying with Parkinson's disease. This biochemical defect is identical to that produced by the neurotoxin 1‐methyl‐4‐phenyl‐1,2,3,6‐tetrahydropyridine (MPTP), which also produces parkinsonism in humans. Complex I comprises 25 polypeptides, seven of which are encoded by mitochondrial DNA. Restriction fragment analysis of substantia nigra DNA from six patients with Parkinson's disease did not show any major deletion. In two cases, there were different novel polymorphisms that were not observed in control brain (n = 6) or blood (n = 34) samples.
Spontaneous orofacial dyskinesias in a captive cynomolgus monkey: Implications for tardive dyskinesia
Authors: Rupniak N. M. J. , Tye S. J. , Steventon M. J. , Boyce S. , Iversen S. D. 
Published: December 2004

AbstractWe describe a syndrome of spontaneous orofacial dyskinesias and cage stereotypies in a singly housed adult cynomolgus monkey never previously exposed to neuroleptic drugs. Abnormal movements were readily suppressed by acute treatment with haloperidol (0.03–0.24 mg/kg i.m.) or SCH23390 (0.05–0.2 mg/kg i.m.) but not by physostigmine (0.005–0.04 mg/kg i.m.) or scopolamine (0.0025–0.04 mg/kg i.m.). The symptomatology and response to pharmacological manipulations was indistinguishable from that previously attributed to chronic neuroleptic treatment in primates. Our findings indicate that neuroleptic‐induced tardive dyskinesias in most primate studies have not been clearly demonstrated.
Prevalence of dystonia in veterans on chronic antipsychotic therapy
Authors: Sethi Kapil D. , Hess David C. , Harp Rollie J. 
Published: December 2004

AbstractThe prevalence of dystonia was studied in 125 veterans on chronic antipsychotic therapy using a detailed and systematic examination. Twenty‐seven out of 125 had dystonic manifestations. The most common areas involved were hands and jaw. There was no relation between the presence or absence of dystonia, and duration of neuroleptic therapy. There was a tendency for tardive akathisia to occur more frequently in patients with dystonia than in those without it (Fisher's exact probability test, p = 0.0656). Tardive dystonia in its milder forms may be more common than currently believed.
Involvement of corticospinal tract in Wilson's disease. A study of three cases with transcranial stimulation
Authors: Berardelli A , Inghilleri M. , Priori A. , Thompson P. D. , Fabri S. , Fieschi C. , Manfredi M. 
Published: December 2004

AbstractMuscle responses evoked by transcranial stimulation were studied in three patients with Wilson's disease. Abnormalities indicating involvement of corticospinal tract were demonstrated in one patient. In keeping with recent evoked potential studies, this finding suggests that lesions in Wilson's disease may affect structures other than the extrapyramidal system.
Neuronal inclusions of Parkinson's disease
Authors: Gibb W. R. G. , Scott T. , Lees A. J. 
Published: December 2004

AbstractTwo distinct neuronal inclusions occur in Parkinson's disease. The Lewy body is the diagnostic hallmark and is recognized by its eosinophilic body and unstained halo. It can be found in specific regions of the nervous system, where its frequency, size, shape, and structure differ. Large neurons of the dorsal vagal nucleus and sympathetic ganglia often contain particularly large quantities of Lewy‐body‐like matter. It consists of filament in the outer part and electron dense material in the core, the outer part staining with silver and with antibodies to neurofilament and tubulin. The pale body is restricted to the substantia nigra and locus ceruleus. It does not react with conventional stains, silver, or neurofilament antibodies, and has a homogeneous structure with a granular and vesicular surface texture. It contains sparse granular matter, vacuoles, and filaments, surrounded by melanin. The Lewy body and pale body may be juxtaposed or contiguous in some cells, but their distinct appearances and structures indicate that they are separate inclusions.
Early‐onset Parkinson's disease
Authors: Giovannini P. , Piccolo I. , Genitrini S. , Soliveri P. , Girotti F. , Geminiani G. , Scigliano G. , Caraceni T. 
Published: December 2004

AbstractThe study was conducted on 120 patients (76 men and 44 women) affected by idiopathic Parkinson's disease (IPD) responsive to L‐dopa and observed for many years. Sixty had clinical onset between the ages of 20–40, representing 10.2% of our PD population; in the others the symptoms began after the 40th birthday. The two groups were matched for sex and length of illness. In all patients a diagnosis of IPD depended on history and clinical and neuroradiological findings. Clinical, pharmacological, evolutive, and epidemiological data were collected on all patients. Thirty‐six patients from each group performed motor dexterity tests (reaction time to expected and unexpected stimuli) and cognitive tests (Wechsler Adult Intelligence Scale, Benton, Short tale, and Zazzo's speed and accuracy test). To assess the prevalence of dementia and the severity of psychiatric side effects of L‐dopa administration, the 60 patients with early‐onset PD were compared with 134 consecutive unselected PD patients. Five percent of early‐onset PD patients had a family history of the disorder. Our study showed that early‐onset PD does not differ fundamentally from the late‐onset form except that the former is characterized by a more rapid establishment of the full‐blown parkinsonian clinical picture and deterioration of the therapeutic efficacy of L‐dopa, with an earlier appearance of side effects. The results of our neuropsychological investigation suggest that early‐onset PD may be a “pure” form of extrapyramidal compromise with exclusively motor manifestations.
Paroxysmal axial spasms of spinal origin
Authors: Brown P. , Thompson P. D. , Rothwell J. C. , Day B. L. , Marsden C. D. 
Published: December 2004

AbstractA 55‐year‐old man with a 4½‐year history of paroxysmal bouts of involuntary large‐amplitude flexion jerks of the trunk and a 1‐year history of persistent rhythmic small‐amplitude movements of the anterior abdominal wall is described. Clinical and electrophysiological evidence suggested that the paroxysmal myoclonus arose in propriospinal systems intrinsic to the spinal cord.
Motor and sensory evoked potentials in progressive supranuclear palsy
Authors: Abbruzzese G. , Tabaton M. , Morena M. , Dall'Agata D. , Favale E. 
Published: December 2004

AbstractMotor potentials evoked in the biceps, thenar, and tibialis anterior muscles by electrical stimulation of the scalp and of the spinal regions were recorded in 12 patients with progressive supranuclear palsy (PSP) and in a control group. Abnormalities of central motor conduction for at least one muscle were present in five patients (41.7%), characterized by a long illness duration. The central sensory conduction time of the median nerve was normal, but five patients showed a depressed frontal N30 wave. These findings support the possible occurrence of functional damage to the corticospinal tracts and to the supplementary motor area in PSP.
Writer's cramp: Treatment with botulinum toxin injections
Authors: Rivest J. , Lees A. J. , Marsden C. D. 
Published: December 2004

AbstractTwelve patients with writer's cramp were treated with injections of botulinum toxin. The overactive muscles were identified by clinical observation of the subjects while they were writing. Repeated injections were given at 2‐week intervals until the optimal response was obtained. Eleven patients reported some benefit, which was considered by seven to be significant. Eight of the 10 patients who had pain reported moderate to significant relief. Five patients had local complications, consisting of disabling weakness of target or neighbouring muscles. These preliminary results suggest that this treatment can be successfully applied to many patients with writer's cramp without performing complex electromyographic recordings while the patients are writing.