bluuebunny/crossref_metadata_2025 huggingface dataset:
Schwingungsrißkorrosion beschichteter Verdichterschaufel‐Werkstoffe
Authors: Hoffmann H. , Magin W. , Schemmer M. , Schmitz F.
Published: December 2004

Schäden an den Verdichterschaufeln von stationären Gasturbinen infolge von Schwingungsrißkorrosion stellen einen großen Teil der beobachteten Ausfallursachen dar. Zusätzlich sind diese Schaufeln je nach Umgebungsbedingungen mehr oder weniger starker Erosion ausgesetzt. Zum Schutz vor diesen Beanspruchungen werden seit Jahren Beschichtungen eingesetzt, wobei in letzter Zeit die zum Teil eingesetzten NiCd‐Schichten vermehrt durch anorganische Schichten aus Chromat/Phosphat‐Bindemitteln mit dispergierten Aluminiumpigmenten, z.B. der Firma SermeTel, ersetzt werden, die einen verbesserten Korrosionsschutz gewährleisten sollen. Im Rahmen eines gemeinsamen Forschungsprojektes der deutschen Gasturbinenhersteller AEG KANIS, BBC und KWU wurden einige dieser Schutzschichten in unterschiedlichen, betriebsnahen Korrosionsmedien auf ihre Schutzwirkung besonders gegen Schwingungsrißkorrosion hin untersucht.

Als Ergebnis kann festgehalten werden, daß die aluminiumpigmentierten Schichten in neutralem Medium bei Raumtemperatur einen guten Korrosionsschutz bieten. Eine der Schichten gewährleistet in stark saurem Medium nur einen zeitlich begrenzten Korrosionsschutz. Bei höheren Temperaturen und auch nach erosiver Vorschädigung werden die ertragbaren Wechselamplituden dagegen sehr stark herabgesetzt. Parallel dazu geprüfte galvanisch oder chemisch abgeschiedene Nickelschichten verbesserten die Korrosionsbeständigkeit nur unwesentlich gegenüber unbeschichteten Proben.
Gitterkonstantenbestimmung in kubischen dünnen Schichten unter thermischer Dehnung
Authors: Zendehroud J. , Thoma K. , Wieder Th.
Published: December 2004

Ein Verfahren zur röntgenographischen Bestimmung der Gitterkonstanten einer kubischen dünnen Schicht, die herstellungsbedingt unter thermischer Dehnung steht, wird angegeben. Das Verfahren liefert zudem die wirksame‐thermische Dehnung. Als Anwendungsbeispiele werden die Gitterkonstanten von ionenplattierten Aluminium‐ und Kupferschichten aus röntgenographischen Messungen mittels eines Seemann‐Bohlin Diffraktometers mit streifendem Strahleinfall ermittelt.
When adding a fuel efficient car increases an automaker's CAFE penalty
Authors: Tenn Steven , Yun John M.
Published: January 2005

We derive the conditions that cause an automaker's Corporate Average Fuel Economy (CAFE) fine to increase when it sells an additional, fuel efficient car. Raising the CAFE standards would broaden the range of fuel economies that produce this effect. Copyright © 2005 John Wiley & Sons, Ltd.
Neurosurgical treatment of severe obsessive‐compulsive disorder associated with Tourette's syndrome
Authors: Kurlan Roger , Kersun Jonathan , Ballantine H. Thomas , Caine Eric D.
Published: December 2004

We describe two patients with Gilles de la Tourette's syndrome (TS) and disabling obsessive‐compulsive and ritualistic behaviors who underwent bilateral radiofrequency anterior cingulotomy. Both achieved a limited but sustained improvement in behavioral symptoms and overall functional abilities. Our observations indicate involvement of limbic structures in this disorder. The procedure should be considered for patients with TS complicated by resistant obsessive‐compulsive disorder.
Exaggerated startle reflexes in an elderly woman
Authors: Colebatch J. G. , Barrett G. , Lees A. J.
Published: December 2004

A 76‐year‐old woman with a 5‐year history of excessive startle is reported. Electrophysiological recordings were made of muscle activation after acoustic and proprioceptive stimulation. The findings are discussed in relation to current knowledge of the startle reflex and classification of startle syndromes. It is concluded that this patient is best regarded as having a pathological exaggeration of the normal startle reflex rather than other causes of stimulus‐sensitive muscle jerks.
Tardive eating dystonia
Authors: Achiron Anal , Melamed Eldad
Published: December 2004

After cessation of long‐term treatment with haloperidol, a 77‐year‐old man developed severe dyskinetic‐dystonic movements involving mainly the tongue and associated also with oromandibular dystonia and blepharospasm that were manifested exclusively during the process of eating and that interfered with feeding. There were no spontaneous involuntary movements nor were they apparent during any other simple or complex activations of the orofacial musculature.
Oral levodopa dose‐response study in MPTP‐induced hemiparkinsonian monkeys: Assessment with a new rating scale for monkey parkinsonism
Authors: Kurlan Roger , Kim Michael H. , Gash Don M.
Published: December 2004

Quantitative measures for the severity of MPTP‐induced parkinsonism and response to antiparkinsonian interventions in monkeys have been lacking. We carried out an oral levodopa dose‐response study in two rhesus monkeys whose left hemiparkinsonism was induced by intracarotid administration of MPTP. A newly developed clinical rating scale of monkey parkinsonism showed a consistent dose‐response relationship for levodopa over the dosage range of 50–3, 500 mg/day. Antiparkinsonian effects appeared at 200 mg/day and were optimal at 1,000–2,000 mg/day. Levodopa also reversed rotational behavior, improved movement times for both the impaired and opposite upper limb, and produced dyskinesias at high dosages. Thus, MPTP‐induced hemiparkinsonism in monkeys closely resembles the human disease condition, is associated with sensitive response measures, and should prove valuable for assessing novel antiparkinsonian therapies.
Alleviation of parkinsonism by antagonism of excitatory amino acid transmission in the medial segment of the globus pallidus in rat and primate
Authors: Brotchie Jonathan M. , Mitchell Ian J. , Sambrook Michael A. , Crossman Alan R.
Published: December 2004

Recent experimental data has made possible the description of the pathophysiological circuitry that mediates parkinsonism. This work has shown that dopamine‐denervated striatal cells discharge abnormally and that this ultimately causes cells in the medial segment of the globus pallidus to become abnormally overactive. The main driving force behind the overactive cells in the medial pallidal segment appears to be excess activity in the afferent pathway to it from the subthalamic nucleus. This pathway is known to use an excitatory amino acid (EAA) as its transmitter. It was therefore hypothesized that local blockade of EAA transmission in the medial segment of the globus pallidus should reverse parkinsonism. This hypothesis was tested in rat and primate models of parkinsonism by the direct injection of the EAA antagonist, kynurenic acid, into the medial segment of the globus pallidus. The results demonstrate that this procedure can reverse parkinsonism in a dose‐dependent manner, and suggest that manipulation of EAA transmission in the medial segment of the globus pallidus may have therapeutic potential for treating parkinsonism.
Interobserver reliability between neurologists in training of Parkinson's disease rating scales. A multicenter study
Authors: Geminiani Giuliano , Cesana Bruno M. , Tamma Filippo , Contri Patrizia , Pacchetti Claudio , Carella Francesco , Piolti Roberto , Martignoni Emilia , Giovannini Paolo , Girotti Floriano , Caraceni Tommaso
Published: December 2004

A multicenter study has been conducted to determine the interobserver reproducibility of four of the most frequently used rating scales for Parkinson's disease: the Columbia University Rating Scale (CURS) and the Webster Rating Scale (WRS), both for assessing clinical signs; the Northwestern University Disability Scale (NUDS); and the Hoehn and Y ahr staging. Four resident neurologists, inexperienced in the use of the four scales, independently examined 48 parkinsonian patients. The extent to which their assessments agreed was determined by calculating the Cohen k index after the scores had been recodified. The physicians' scores agreed substantially for the CURS and the Hoehn and Y ahr scale, while those for the NUDS and the WRS agreed only moderately. Analysis of individual item scores within the scales suggests improvements that would offer greater interobserver consistency.
Effect of LY 171555 and CY 208‐243 on tremor suppression in the MPTP monkey model of parkinsonism
Authors: Gomez‐Mancilla Baltazar , Boucher René , Bédard Paul J.
Published: December 2004

The antitremor effect of the D2 agonist LY 171555 and of the D1 agonist CY 208‐243 alone and in combination was tested in a monkey previously rendered parkinsonian by MPTP and displaying exceptionally a rest termor in the limbs. The D2 agonist suppressed rest tremor in a dose‐dependent fashion. The D1 agonist by itself had no effect but it potentiated the effect of a small dose of LY 171555.
Milacemide therapy for Parkinson's disease
Authors: Giuffra M. E. , Sethy V. H. , Davis T. L. , Mouradian M. M. , Chase T. N.
Published: December 2004

The clinical effects of central glutamatergic stimulation by the glycine prodrug milacemide were studied in six patients with Parkinson's disease under double‐blind, placebo‐controlled conditions. When administered as monotherapy at a single oral dose of 1,200 mg, the drug increased overall parkinsonian severity transiently, mostly due to an effect on rigidity. Milacemide did not, however, alter levodopa‐induced dyskinesias. These results support the view that drugs acting on the glutamatergic system can influence motor function in patients with extrapyramidal movement disorders and that pharmaceutical agents that selectively block certain subtypes of glutamate receptors may ameliorate parkinsonian symptoms.
Asymmetric catalepsy after right hemisphere stroke
Authors: Saver Jeffrey L. , Greenstein Penny , Ronthal Michael , Mesulam M.‐Marsel
Published: December 2004

We describe the appearance of left hemineglect and striking cataleptic posturing, more prominent in left‐sided extremities, in a patient without psychiatric illness. Neuroimaging demonstrated a large posterior right hemisphere infarct involving the parietal, occipital, and temporal lobes, the insula, and caudate. Additional movement abnormalities that comprise the full catatonia syndrome were absent, including stereotypy, mannerisms, ambitendency, automatic obedience, mutism, negativism, and echopraxia. Catatonia has been reported to be produced by lesions of diverse etiology affecting the frontal lobe, limbic system, diencephalon, or basal ganglia. In these cases, catalepsy has been manifest only rarely, and motor signs that are present are generally bilateral. This case demonstrates that asymmetric catalepsy can be produced by right hemisphere stroke, and provides partial support for earlier clinical literature relating catelepsy and the parietal lobe.
Basal ganglia infarction as a possible cause of cervical dystonia
Authors: Molho Eric S. , Factor Stewart A.
Published: December 2004

Cervical dystonia (CD) is usually an idiopathic disorder that results in abnormal movements and painful postures of the neck. Although symptomatic CD caused by focal CNS lesions has been described in the literature, it is an exceedingly rare phenomenon. We report two women who had an abrupt onset of CD at the ages of 39 and 68 years. Each patient had rotation of the head to the right and was found to have a lacunar infarction in the left putamen on magnetic resonance imaging scan. The abrupt onset of symptoms and appropriate location and laterality of the cerebral lesions suggest an etiologic link between the infarctions and the patients' CD. These cases are the first reports of CD possibly caused by basal ganglia infarction.
Administration of the new COMT inhibitor OR‐611 increases striatal uptake of fluorodopa
Authors: Guttman M. , Léger G. , Reches A. , Evans A. , Kuwabara H. , Cedarbaum J. M. , Gjedde A.
Published: December 2004

L‐Dopa is metabolized to 3–O‐methyldopa (3OMD) by catechol‐O‐ methyltransferase (COMT). This reduces the amount of L‐dopa available for entry into brain. We studied the effect of OR‐611, a new COMT inhibitor, on plasma and brain 6‐[18F]‐fluoro‐L‐dopa (6FD) metabolism in cynomolgus monkeys with positron emission tomography (PET). OR‐611 pretreatment substantially reduced plasma 6FD metabolism to 3‐O‐methylfluorodopa (3OMFD). PET measurements of striatal 6FD concentrations showed an average 2.3‐fold increase following OR‐611 pretreatment, compared to the same animals in the control state. OR‐611 inhibits plasma metabolism of 6FD and increases brain uptake of this L‐dopa analog. OR‐611 appears to be a promising agent as an adjunct to L‐dopa for the treatment of patients with Parkinson's disease.
Rating impairment and disability in Parkinson's disease: Evaluation of the unified Parkinson's disease rating scale
Authors: van Hilten J. J. , van der Zwan A. D. , Zwinderman A. H. , Roos R. A. C.
Published: December 2004

Although the Unified Parkinson's Disease Rating Scale (UPDRS) is widely used to monitor disease progression and drug efficacy, no attempts have been made to evaluate its scientific and clinical quality. Poor clinical sensibility of items in the activities of daily living (ADL) section and redundancy of items in the motor examination (ME) section prompted us to determine if the number of items in these sections could be reduced to a smaller, equally sensitive set that would describe the data as relibly as did the original set of items. Therefore, we assessed 111 patients with idiopathic Parkinson's disease on the UPDRS and Hoehn and Yahr staging scales. Our results show that the ADL (13 items) and ME (14 items) sections can be reduced to 8 items each without loss of reliability or validity. Our report is preliminary and needs validation.
Severe evening dyskinesias in advanced Parkinson's disease: Clinical description, relation to plasma levodopa, and treatment
Authors: Zimmerman Thomas R. , Sage Jacob I. , Lang Anthony E. , Mark Margery H.
Published: December 2004

We report four patients with Parkinson's disease who had an unusual pattern of severe chorea and dystonia in the evenings only. The temporal pattern of abnormal movements and simultaneous monitoring of plasma levodopa and clinical state were consistent with dyskinesias associated with subtherapeutic (low dopa dyskinesias) rather than peak concentrations of levodopa (high dopa dyskinesias). In two patients, addition of a direct‐acting dopamine receptor agonist was helpful in ameliorating this complication of anitparkinson therapy.
Naltrexone, an opiate antagonist, fails to modify motor symptoms in patients with Parkinson's disease
Authors: Rascol Olivier , Fabre Nelly , Blin Olivier , Poulik Janet , Sabatini Umberto , Senard Jean‐Michel , Ané Michèle , Montastruc Jean‐Louis , Rascol André
Published: December 2004

One month of adjunct treatment with naltrexone (100 mg/day) was compared with placebo in a double‐blind, randomized, cross‐over design in two groups of patients with Parkinson's disease. The first group was composed of 10 patients with a moderate motor impairment insufficiently controlled by monotherapy with bromocriptine. The second group was composed of eight patients with L‐dopa‐induced peak‐dose dyskinesia. Naltrexone as compared with placebo did not demonstrate any significant change in motor function in either group. These negative clinical results do not support a significant role of endogenous opioid systems in the pathophysiology of motor impairment in Parkinson's disease.
Respiratory chain and mitochondrial deoxyribonucleic acid in blood cells from patients with focal and generalized dystonia
Authors: Reichmann Heinz , Naumann Markus , Hauck Sabine , Janetzky Bernd
Published: December 2004

An increaseing number of neurodegenerative diseases seem to be associated with or even due to disturbancs of cerebral energy metabolism. One generally accepted example is complex I deficiency in substantia nigra from patients with Parkinson's disease. Reports on a complex I defect in platelets from patients with dystonia led us to check for disturbances of the respiratory chain or of the mitochondrial genome in isolated mitochondria from patients with focal or generalized dystonia. We could not confirm the idea of mitochondrial disturbance in platelets from patients with dystonia because we did not find abnormal enzyme activities or any deletions of the mitochondrial genome. Thus, we do not think that blood cells such as platelets can serve as markers for neurodegenerative disorders such as dystonia.
Dystonia as the major manifestation of Leigh's syndrome
Authors: Lera Gabriel , Bhatia Kailash , Marsden C. David
Published: December 2004

We report eight patients who had a progressive illness dominated by generalised dystonia and who had clinical and imaging features suggestive of Leigh's syndrome (LS). Six of the eight cases were male. Early development was usually normal but three cases exhibited impaired mental and/or motor development, and three others had a history of an earlier unexplained encephalopathy or febrile illness. The onset of the dystonia occurred at a mean age of 3 years (range 2 months‐7 years). All had abnormalities in the basal ganglia on brain imaging; symmetrical bilateral lucencies or calcification were seen in the basal ganglia on computed tomography scan in five cases, and high signal lesions were evident in these regions on T2‐weighted magnetic resonance imaging sequences in seven cases. Other causes of such changes in the basal ganglia were excluded by appropriate investigations. Raised blood lactate levels were found in four of the eight patients. Muscle biopsies were done in seven patients but histology and histochemistry were normal. The common mitochondrial DNA mutations associated with LS in mitochondrial encephalopathies were not found in the six cases examined. LS presenting as a pure dystonic syndrome is uncommon, but should be considered in the differential diagnosis of symptomatic dystonia presenting in childhood.
Anorectal manometry in the assessment of anorectal function in Parkinson's disease: A comparison with chronic idiopathic constipation
Authors: Ashraf Waseem , Pfeiffer Ronald F. , Quigley Eamonn M. M.
Published: December 2004

We investigated the role of anorectal manometry in evaluating constipation and anorectal function in 15 patients with Parkinson's disease (PD) and compared results with those of 9 patients with idiopathic constipation (IC) and 8 control (C) subjects. Anal sphincter pressures on voluntary squeeze were lower in the PD patients. Sustained squeeze pressures (mm Hg C versus IC versus PD: 46.8 ± 5.2 versus 31.2 ± 3.6 versus 26.6 ± 3.9; p < 0.05 PD versus C), squeeze duration (seconds: 53.6 ± 2.5 versus 48.5 ± 4.1 versus 33.6 ± 9; p < 0.05 PD versus C) and squeeze index (area under the squeeze curve: 44.0 ± 2.9 versus 34.5 ± 3.3 versus 21.4 ± 2.9; p < 0.001 PD versus C) were significantly lower in the PD group in comparison to the control group. In contrast, none of the parameters of anorectal manometry differed between controls and patients with idiopathic constipation. Some Parkinson's disease patients demonstrated an abnormal, hypercontractile response on testing of the rectoanal inhibitory reflex. Anal sphincter length, basal sphincter pressures, maximal squeeze pressures, extent of relaxation on rectoanal inhibitory reflex and threshold volume for rectal sensation were similar in the three groups. We conclude that an impaired squeeze response is a specific feature of anorectal function in Parkinson's disease. This may indicate direct involvement of the pelvic floor musculature by the parkinsonian disease process.
Effects of tolcapone in Parkinson's patients taking L‐dihydroxyphenylalanine/carbidopa and selegiline
Authors: Davis T. L. , Roznoski M. , Burns R. S.
Published: December 2004

A double‐blind, placebo‐controlled, crossover trial of tolcapone (RO 407592), a potent reversible inhibitor of catechol‐O‐methyltransferase (COMT), was performed in 10 Parkinson's disease (PD) patients to determine single‐dose safety and efficacy. All subjects were chronically treated with stable doses of selegiline and L‐dihydroxyphenylalanine (L‐DOPA)/carbidopa. Tolcapone was administered in four single ascending doses (50‐800 mg) randomly paired with placebo. Motor ratings were performed every 30 min for 6 h. At higher doses (400 mg and 800 mg), tolcapone prolonged the antiparkinson response of L‐DOPA. Nausea was the most common adverse effect of the tolcapone—L‐DOPA/carbidopa—selegiline combination. Adverse cardiovascular effects were not seen. The acute inhibition of amino acid decarboxylase, monoamine oxidase‐B, and COMT is well tolerated and prolongs the L‐DOPA response in PD patients. Tolcapone may be a safe and useful adjunct to L‐DOPA/carbidopa in PD patients taking selegiline.
Dystonia in a patient with deletion of 18q
Authors: Gordon Mark Forrest , Bressman Susan , Brin Mitchell F. , de Leon Deborah , Warburton Dorothy , Yeboa Kwame , Fahn Stanley
Published: December 2004

This is the first reported case of dystonia with a partial deletion of the long arm (q) of chromosome 18. Neurologic findings in the 18q‐ syndrome include mental retardation, seizures, nystagmus, incoordination, tremor, and chorea. A 36‐year‐old woman with an 18q terminal deletion [Karyotype 46, XX, del (18)(q22.2)] had hypothyroidism, diabetes mellitus, borderline intelligence, short stature, short neck, sensorineural hearing loss, and sensorimotor axonal neuropathy. Parents' Karyotypes were normal. She had had incoordination and writing difficulty since childhood. Posturing and tremor of the head began at age 16, followed by arm tremors. She had jaw deviation and tremor, neck tremor with retrocollis, involuntary pronation of the right arm, coarse postural and severe action tremor, and tight pen grip with dystonic wrist extension on writing. The 18q‐ syndrome should be added to the list of genetic causes of secondary dystonia. A karyotype analysis should be considered in secondary dystonias, particularly when there are associated features such as short stature and endocrinopathies.
Effects of selective serotonergic ligands on posthypoxic audiogenic myoclonus
Authors: Matsumoto Rae R. , Hussong Matthew J. , Truong Daniel D.
Published: December 2004

Male Sprague‐Dawley rats underwent cardiac arrest and resuscitation, subsequently exhibiting posthypoxic myoclonus. The audiogenic posthypoxic myoclonus in these animals could be attenuated with the following drugs: 5‐hydroxytryptophan (5‐HTP, serotonin [5‐HT] precursor), N‐(3‐trifluoromethylphenyl) piperazine hydrochloride (TFMPP, 5‐HT1B/1C/2 agonist), (±)‐2,5‐dimethoxy‐4‐iodoamphetamine hydrobromide (DOI, 5‐HT2 agonist), and l‐(m‐chlorophenyl)‐biguanide hydrochloride (m‐CPBG, 5‐HT3 agonist). In contrast, the following drugs were ineffective: (±)‐8‐hydroxy‐dipropylaminottetralin hydrobromide (8‐OH‐DPAT, 5‐HT1A agonist), buspirone hydrochoride (5‐HT1A agonist), 7‐trifluoromethyl‐4(4‐methyl‐1‐piperazinyl)‐pyrrolo[1,2‐a]quinoxaline maleate (CGS 12066B, 5‐HT1B agonist), ketanserin tartrate (5‐HT2 antagonist), methysergide maleate (5‐HT2 antagonist), fluoxetine (5‐HT uptake blocker), and saline (vehicle). The data suggest that enhancement of serotonergic activity, particularly through 5‐HT2 and 5‐HT3 receptors, have therapeutic potential for the treatment of posthypoxic myoclonus.
Tardive tourettism after exposure to neuroleptic therapy
Authors: Bharucha Kersi J. , Sethi Kapil D.
Published: December 2004

A case of neuroleptic‐induced adult‐onset tardive tourettism is presented with video documentation. After prolonged neuroleptic therapy, the patient developed motor and vocal tics at 36 years of age. The tics were identical to those seen in childhood‐onset Tourette's syndrome. These cases are rare and have been consdered by some to represent tardive akathisia. Previous reports of tourettism after neuroleptic therapy are reviewed.
Partial reversal of increased preproenkephalin messenger ribonucleic acid (mRNA) and decreased preprotachykinin mRNA by foetal dopamine cells in unilateral 6‐Hydroxydopamine–Lesioned rat striatum parallels functional recovery
Authors: Zeng B.‐Y. , Jenner P. , Marsden C. D.
Published: December 2004

In situ hybridization histochemistry was used to investigate the expression of striatal preproenkephalin and preprotachykinin messenger ribonucleic acid (mRNA) in rats with 6‐hydroxydopamine lesions of the nigrostriatal pathway followed 4 weeks later by implantation of foetal dopamine cells into the denervated striatum. Striatal dopamine deafferentation caused an (+)‐amphetamine‐induced rotational asymmetry, an increase in striatal preproenkephalin mRNA message, and a decrease in striatal preprotachykinin mRNA message relative to control animals. Two months after grafting a foetal ventral mesencephalon suspension, there was reversal of the rotational asymmetry to (+)‐amphetamine. At this time the increase in striatal preproenkephalin mRNA was significantly attenuated and the decrease in preprotachykinin mRNA was partially reversed compared to animals with a 6‐hydroxydopamine lesion alone. Subregional analysis showed the attenuation of the increase in preproenkephalin mRNA to occur in dorsolateral, dorsomedial and ventromedial, but not ventrolateral, striatal subdivisions. The partial reversal of the decreased preprotachykinin mRNA density after grafting was only statistically significant in the DM and VM subdivisions. These results demonstrate graft‐induced partial recovery of striatal function, as judged by preproenkephalin and preprotachykinin mRNA levels, within 2 months of transplantation.
Sternomastoid function during hemispheric suppression by amytal: Insights into the inputs to the spinal accessory nerve nucleus
Authors: DeToledo John C. , Dow Robert
Published: December 2004

The debate as to whether the sternomastoids receive ipsilateral, contralateral, or bilateral cortical innervation is based largely on the observation of stroke patients and, to a lesser extent, on animal experimentation. The variability of vascular lesions, the lack of pathology correlation in the early reports, and the differences in posture between humans and laboratory animals contributed to the controversy. We studied the function of the sternomastoid (SM) muscles during transient, complete left hemiplegia in 18 right‐handed patients undergoing a Wada test. After injection in the right internal carotid artery (ICA), 14 patients were able to lift and turn their heads both to the right and to the left on command. Ten of the 14 patients who were able to follow commands after the injection had weakness of the right sternomastoid compared with the left. Our findings demonstrate that the left hemisphere can activate both the right and the left sternomastoid muscles during suppression of the right hemisphere. The sternomastoids receive bilateral hemispheric innervation and the maximal input comes from the ipsilateral hemisphere.
Polysomnographic sleep measures in patients with uremic and idiopathic restless legs syndrome
Authors: Wetter Thomas C. , Stiasny Karin , Kohnen Ralf , Oertel Wolfgang H. , Trenkwalder Claudia
Published: December 2004

In the present study, the nocturnal electroencephalographic sleep pattern, the number of periodic leg movements (PLM) during sleep and wakefulness, and the subjective sleep parameters of patients with uremic (n = 10) and idiopathic (n = 17) restless legs syndrome (RLS) were compared. The main finding was that the total number of PLM (p = 0.019), the PLM index (p = 0.018), and the PLM index while awake (p = 0.003) were significantly higher in patients with uremic RLS compared with patients who had idiopathic RLS. Additionally, both groups showed a distinct time‐of‐night pattern of PLM activity. Polysomnographic measures of sleep continuity (total sleep time, sleep efficiency, sleep onset latency, time awake) and sleep architecture (amount of nonrapid eye movement sleep stages 1, 2, 3, and 4 and the amount of rapid eye movement sleep) did not differ between uremic and idiopathic RLS patients. With regard to subjective paramaters, sleep quality was estimated to be worse in uremic RLS (p = 0.033), whereas other paramaters (for example, severity of RLS, quality of life) did not differ between the two groups. It is suggested that uremia itself worsens the motor symptoms of RLS, probably as a result of increased excitability.
Comparative chemical means of assessing polyethylene oxidizability
Authors: Meltzer Theodore H. , Goldey Richard N.
Published: December 2004

This paper compares results of four accelerated oxidation tests: the hot milling test, reaction with fuming nitric acid, absorption of oxygen gas at elevated temperature and the redox system—polyethylene—lead peroxide ignition test. The length of the induction period, is a product of antioxidant concentration but not of the inherent oxidizability of the resin. Discrepancies between induction periods as measured by oxygen absorption and hot milling differ because in the former the volume of pure oxygen absorbed is measured and in the latter the electrical consequences of air oxidation. In addition other polymeric degradation occur in milling. Nitric Acid treatment measures the effect of nitric acid upon the specific viscosity and is useful for chain scission comparisons. The ignition tests reflect both inherent oxidizability and presence of antioxidant. All four tests reflect oxidation parameters.
Novel phosphorus containing polymers
Authors: Kindley Lee M. , Podall Harold E. , Filipescu Nicolae
Published: December 2004

Tris‐hydroxymethylphosphine oxide (THPO) derived from commercially available tetrakishydroxy‐methylphosphonium chloride (THPC), was studied for its flame retardant properties in reactions with carboxylic acids, anhydrides, diisocyanates, urea, phenol, acyl and aroyl halides. Then the monobenzylated derivative of THPO referred to as BHPO was studied, which is more stable and more reactive with difunctional molecules.
Dynamic mechanical behavior during the thermosetting curing process
Authors: Lewis Armand F.
Published: December 2004

The application of a free vibration technique to the study of the cross‐linking of an epoxy resin by an amine is demonstrated. Curing curves are presented showing the changes in dynamic mechanical flexural modulus and damping during reaction. At room temperature, the glass transition point is reached after a conversion of about 65% of the epoxide groups. Comparisons of the dynamic mechanical and infrared curing curves indicate a lowering of the reaction rate after this point is reached. Finally, an activation energy for the epoxy‐amine cross‐linking reaction is calculated.
Impact behavior of a nitrile elastomer
Authors: Barkan P. , Sirkin M. F.
Published: December 2004

This investigation studies the behavior of several cylindrical specimens of a Buna‐N elastomer subjected to compression impact by a finite mass. Initial strain rates fall in the range between 40/sec and 400/sec, with maximum nominal strains up to 0.4. It is shown that values of nominal stress, true and nominal strain, energy dissipation and impact duration can be correlated with elastomer geometry and initial kinetic energy by means of two parameters derived from an analysis of a linear viscoelastic model. Other sources of variability of elastomer behavior are discussed.
Oxygen absorption studies on polypropylene
Authors: Bell G. W. , Heyd C. E.
Published: December 2004

An investigation of the effect of sample dimensions on the oxidation of polypropylene is described. The results are used to select testing conditions. Two examples of the utility of the method are presented. First, a control method for uninhibited polypropylene and, secondly, an investigation of the synergistic effect between 2,6‐di‐t‐butyl‐p‐cresol and dilaurylthiodipropionate.
Structure‐property modifications by fabrication operations
Authors: Maxwell B. , Gogos C. G. , Blyler L. L. , Mineo R. M.
Published: December 2004

Studies of polymer morphology under ideal conditions approaching equilibrium structures have been shown to be valuable in the development of an understanding of the relationship of properties to structure. Practical fabrication operations do not permit the achievement of equilibrium structures in commercial products and its is therefore necessary to study the effects of processing on the actual structures that result. In addition, an understanding of the effects of processing variables on properties permits the development of fabrication operations which can be directed toward the improvement of properties. Topics covered include the effects of hydrostatic pressure during processing, effects of combinations of pressure and thermal history, relationships between thermal history and crystallization rates in isotactic polymers and the kinetic and morphological effects of flow deformation on crystallizable plastics.
Mechanical and dielectric relaxation of crystalline polymers in relation to degree of crystallinity and morphology
Authors: Passaglia E.
Published: December 2004

Mechanical and dielectric relaxation as related to the morphology of crystalline polymers is reviewed. The behavior with temperature of the imaginary part of the complex dielectric constant and the mechanical loss factor, tan δ, at constant frequency is discussed in detail for two typical crystalline polymers: poly(chlorotrifluoroethylene) and polypropylene. Three relaxations are typically observed: a low temperature relaxation occurring at temperatures below the dilatometric glass transition temperature; a glass temperature relaxation occurring near the glass transition temperature; and a high temperature relaxation occurring between the glass temperature and the melting point. The activation parameters are given for these relaxations, and the influence of morphology on them is discussed along with possible molecular interpretations.
Melt viscosity—temperature dependence of some low density polyethylenes
Authors: Mendelson R. A.
Published: December 2004

The melt viscosities of three low density polyethylenes of widely varying melt indices were studied as a function of temperature over a broad range of shear rates and shear stresses. Apparent viscosities at constant shear stress could be fitted adequately to a simple Arrhenius equation over the entire temperature range studied. However, pronounced curvature of the log ηa–1/T curves was observed for apparent viscosities at constant shear rate. The apparent activation energies for viscous flow at constant shear stress were found to decrease slowly with increasing shear stress and also to decrease with decreasing molecular weight. A temperature‐shear rate superposition was demonstrated to hold, and the shift factor dependence on temperature was determined.
The oxyluminescence of polymers III. Effects of oxidation and structure; Mechanisms involved
Authors: Schard M. P.
Published: December 2004

Studies of polypropylene oxyluminescence show the luminous intensity to be dependent upon the degre of oxidation. The length of the low intensity level portion of the luninescence curve, or pseudo induction period, was found to be a measure of the useful stabilizer life, and the intensity of this portion indicative of the effectiveness of stabilization. The effect of peroxide decomposers was studied and results indicate that peroxide reactions are major producers of luminescence. Analysis of the accepted modes of polymer oxidation, in view of our luminescence findings, indicate that the rate of luminescence buildup should depend upon ease of R. formation and the luminous intensity should be dependent on peroxy radical concentration. The effect of tertiary‐carbon content on luminescence was also investigated, and luminous intensity was found to be dependent upon the amount of polymer branching. Model Compounds having slight structural variations were examined and were found to produce different intensity‐time curves during oxidation, which may be attributed to ease of formation of a reactive site and subsequent peroxy radical reactions.
Experimental investigations on fracture of polymers
Authors: Sharma M. G. , Lim C. K.
Published: December 2004

This article describes the experimental investigations on fracture of a polymeric material under various uniaxial and biaxial stress fields, at controlled rates of loading. The biaxial stress fields have been produced by subjecting tubular specimens to pure internal pressure, internal pressure combined with tension loading, pure torsion and torsion combined with tension loadings. The experimental arrangements developed for conducting the above tests have been described. Examination of fractured specimen subjected to various biaxial stress fields indicates that the fractured surface is mostly along the plane of maximum normal stress. However, the mode of fracture in the case of pure compression test resembles that of a brittle material. From the experimental fracture data, limiting failure curves for the material have been obtained corresponding to various maximum extension ratio rates. The experimental failure data were compared with various criteria of failure essentially developed for metals. It was found that none of the classical failure criteria applies to the material tested.
The effect of silane coupling agents in improving the properties of filled or reinforced thermoplastics
Authors: Sterman S. , Marsden J. G.
Published: December 2004

The application of silane coupling action produces significant improvements in physical properties in various thermpolastic resin systems. Both glass‐reinforced thermoplastics and the more conventional filled thermoplastic resin systems were studied. An order of specificity between resin and coupling agent exists for thermoplastic resins similar to that of thermosets. The interaction with thermosets is considered copolymerization, wereas that with thermoplastics is not yet clearly defined. The silanes are incorporated by pre‐treatment (best for glass reinforcement) or by addition during normal compounding. Fillers are added for a specific result, often with sacrifice of physical strength. Data presented show that silane addition upgrades filled thermoplastics to the level of clear resins and sometimes above. The effect of silanes on electrical properties of filled thermoplastics are also reported.
Fundamentals of plasticating extrusion. II. Experiments
Authors: Marshall D. I. , Klein I.
Published: December 2004

Experiments were performed to develop quantitative information for designing plasticating extruders for low density polyethylene. Screw design variables explored included feed section length, compression section taper, and minimum channel depth. Operating variables included were screw speed, barrel temperature, and back pressure. A moving picture film illustrates temperature action and cross‐channel temperature distribution for some typical experiments using a new type of extruder screw for 2.5 inch and 8 inch diameter extrusion. The information gathered was used to obtain relations between performance and screw dimensions and revealed an optimum combination of feed section length and compression taper.
Bisphenol‐A bimodal epoxy resins. Part I: The dynamic mechanical characterization of a 6300 (340/22,500) weight average molecular weight system
Authors: Holmes Gale A. , Letton Alan
Published: December 2004

By using an advanced epoxy resin of 22,500 weight average molecular weight two bimodal systems of 6300 weight average molecular weights were prepared. By altering the curing procedure normally used to cure epoxy resins and high molecular weight resins we have succeeded in minimizing the difficulty associated with preparing bimodal epoxy resin systems. The ultimate Tg of these bimodal systems is associated with the phase morphology and controlled by the curing conditions employed. For the completely phase separated bimodal system a Tg of 473 K is reported and for the partially phase separated system a Tg of 466 K is reported. Equations were developed for predicting the equilibrium shear modulus of these bimodal systems. Theoretical predictions based on these equations were found to be consistent with experimental results.
Organosoluble, low‐dielectric‐constant fluorinated polyimides based on 2,6‐bis(4‐amino‐2‐trifluoromethylphenoxy)naphthalene
Authors: Yang Chin‐Ping , Hsiao Sheng‐Huei , Chung Cheng‐Lin
Published: January 2005

A novel fluorinated bis(ether amine) monomer, 2,6‐bis(4‐amino‐2‐trifluoromethylphenoxy) naphthalene, was prepared through the nucleophilic aromatic substitution reaction of 2‐chloro‐5‐nitrobenzotrifluoride and 2,6‐dihydroxynaphthalene in the presence of potassium carbonate, followed by catalytic reduction with hydrazine and Pd/C in ethanol. A series of novel trifluoromethylated polyimides were synthesized from the diamine with various commercially available aromatic tetracarboxylic dianhydrides using a two‐stage process with thermal imidization of poly(amic acid) films. Most of the resulting polyimides were highly soluble in a variety of organic solvents and could afford transparent and tough films via solution casting. These polyimides exhibited moderately high glass transition temperatures (Tgs) of 249–311 °C, high thermal stability and good mechanical properties. Low moisture (0.19–0.85 %), low dielectric constants (2.49–3.59 at 10 kHz), and low color intensity were also observed. For a comparative study, a series of analogous polyimides based on 2,6‐bis(4‐aminophenoxy)naphthalene were also prepared and characterized. Copyright © 2005 Society of Chemical Industry
Versatile preparation of poly(1,4‐phenylenevinylene‐co‐1,4‐phenylene‐1,2‐ethanediyl) by CVD polymerization of p‐(methoxymethyl)benzyl chloride
Authors: Trinh Tung Ngo , Yu Young‐Jun , Kim Kyungkon , Joo Sung‐Hoon , Park Yongsup , Jin Jung‐Il
Published: January 2005

It was demonstrated that a series of copolymers consisting of 1,4‐phenylenevinylene (PV) and 1,4‐phenylene‐1,2‐ethanediyl (PE) units could be prepared from a single monomer, p‐(methoxymethyl)benzyl chloride, via the chemical vapor deposition polymerization (CVDP) method. The composition of the copolymers could be varied simply by altering the monomer activation temperature. The higher the temperature, the lower the content of the PV unit. The photo (PL)‐ and electroluminescence (EL) properties of the copolymers that revealed a blueshift when compared with PPV strongly depend on the amount of the PE units incorporated. The external quantum efficiencies of the electroluminescence devices having the configuration of ITO/PEDOT‐PSS/copolymer/Al‐Li were higher than that of PPV, which can be ascribed to the improved confinement of excitons. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 742–751, 2005
Analytical solutions to mathematical models of the surface and bulk erosion of solid polymers
Authors: Lyu Suping , Sparer Randall , Untereker Darrel
Published: January 2005

The process by which polymeric materials hydrolyze and disappear into their environments is often called erosion. Two types of erosion have been defined according to how the hydrolysis takes place. If hydrolysis occurs throughout the entire specimen at the same time, it is called bulk erosion. If the hydrolysis is mainly confined to a region near the surface of the specimen and the surface continuously degrades by moving inward, it is termed surface erosion. In this article, a kinetic relationship for bulk erosion is developed. This relationship provides a method for estimating the hydrolysis kinetic constants for bulk‐eroding polymers. This same relationship is also applicable to surface erosion at a microscopic level. Through its combination with a diffusion–reaction equation and the provision of moving boundary conditions, an analytical solution to the steady‐state surface‐erosion problem is obtained. The erosion rate, erosion front width, and induction time can all be expressed as simple functions of the rate of polymer bond hydrolysis, water diffusivity, and solubility, plus other parameters that can be experimentally determined. The erosion front width is the product of the induction time and the erosion rate. The ratio of the erosion front width to the polymer specimen thickness is a parameter that determines whether the specimen undergoes surface or bulk erosion. Theoretical results are compared with experimental observations from the literature, and agreement is found. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 383–397, 2005
Singularity of Crushing Behavior of Single Particles near Their Natural Period
Authors: Yashima Saburo , Hashimoto Hitoshi , Yashima Saburo
Published: December 2004

Within grinding machines the load acting on the particles and the loading rate are widely distributed. According to studies on the breakage mechanism of brittle materials, the mechanical properties which relate to breakage vary with the loading rate. In order to elucidate the grinding mechanism within the grinding machines, it is necessary to obtain the relationships between these properties and loading rate.

In this study, the variation of strength, fracture energy, new surface area produced by fracture and fracture energy with the loading rate (ranging from 10−1 to 109 N/s) was investigated by means of compression tests on a large number of spherical specimens. As a result, a singularity of crushing behavior was observed under an impact loading corresponding to a duration of time of loading the same as the natural period of the spherical specimen. The crushing efficiency is especially at its maximum.
Asbestos Particle Characteristics Important for the Filter Cake Formation
Authors: Hraste Marin , Vidović Krunoslav
Published: December 2004

Two types of asbestos fiber, chrysotile and amosite, form filter cakes of different permeabilities while having a similar degree of dispersion.

The filter cake resistance depends on the disperse phase characteristics and the conditions of cake formation. The main reason for the effects mentioned is different particle flexibility influenced by the specific structure of each type of asbestos particle.

The flexible chrysotile fibers in the cake form dense and rigid, amosite, porous deposits. An increase in the velocity of the suspended chrysotile particles, caused by pressure difference and agitation, results in significant differences in filter cake resistance.
Über einige höhere Benzolhomologe
Authors: Halse O. M.
Published: January 2005

Im ganzen sind in dieser Weise 14 tertiäre Benzolhomologe dargestellt worden. Dazu kommen noch die vier von Schreiner dargestellten. Es lassen sich noch weitere 14 voraussehen, deren Synthesen bald in Angriff genommen werden sollen. Es wird sich dann herausstellen, inwieweit Gesetzmäßigkeiten in bezug auf physikalische Konstanten und andere Eigenschaften beobachtet werden können. Mit dem bis jetzt vorliegenden Material lassen sich einstweilen solche nicht ermitteln.
Die Reduktionskatalyse ungesättigter Fette und Fettsäuren durch Nickeloxyde
Authors: Erdmann E.
Published: January 2005

1. Durch die von Bedford und mir veröffentlichte Untersuchung über die Nickeloxyde als Reduktionskatalysatoren ist zum ersten Mal die unwiderleglich richtige Tatsache festgestellt worden, daß Nickeloxyde in besonders glatter Weise Wasserstoff auf ungesättigte Fette und Fettsäuren unter Atmosphärendruck zu übertragen vermögen.
Die Reindarstellung des Propylens
Authors: Trautz Max , Winkler Karl
Published: January 2005

Eine Anordnung zur katalytischen Darstellung des Propylens aus Propylalkohol oder besser Isopropylalkohol mit Graphittiegelmasse als Katalysator (nach Sabatier‐Senderens) und eine Anordnung zur Reinigung des Gases wird angegeben. Sein Siedepunkt wird zu −47,8° bei 750 mm, seine Dichte bei −79° zu 0,647, sein Brechungsindex für die gelbe He‐Linie (5876) zu 1,00102 bestimmt und festgestellt, daß die spezifischen Volumina von Propylen‐Trimethylengemischen bei −79° sich innerhalb der Fehlergrenze von etwa 7 v. T. additiv verhalten.
Berlinerblau und Turnbullsblau. V
Authors: Müller Erich
Published: January 2005

Die potentiometrische Verfolgung der Bildung von Berlinerblau und Turnbullsblau bestätigt die Zusammensetzung, die ich früher auf Grund analytischer Daten über die Struktur dieser Körper geäußert habe, insonderheit lehrt sie, daß die bei den verschiedenen Mischungsverhältnissen gebildeten verschiedenen Verbindungen die Eigentümlichkeit besitzen, sich ineinander fest zu lösen.