bluuebunny/crossref_metadata_2025_split huggingface dataset:
Stripping Voltammetric Determination of Zirconium with Complexing Preconcentration of Zirconium(IV) at a Morin‐Modified Carbon Paste Electrode
Authors: Liu Shumei , Li Junan , Mao Xun 
Published: November 2003

AbstractA sensitive, selective and economic stripping voltammetry is described for the determination of trace amounts of zirconium at a morin‐modified carbon paste electrode (morin‐MCPE). Zirconium(IV) can be preconcentrated on the surface of the morin‐MCPE due to forming the Zr(IV)–morin complex. The complex produces two second‐order derivative anodic peaks at 0.69 V (vs. SCE) and 0.75 V when linear‐scanning from 0.0 to 1.0 V. The optimum analytical conditions are: 2.2 mol L−1 HCl, 0.0 V accummulation potential, 90 s accummulation time, 250 mV s−1 scan rate. A linear relationships between the peak currents at 0.75 V and the Zr(IV) concentration are in the range of 2.0×10−8 to 3.0×10−6 mol L−1. The detection limit is 1.0×10−8 mol L−1 (S/N=3) for 120 s accumulation. The RSD for determination of 4.0×10−7 mol L−1 Zr(IV) is 4.8% (n=8). The proposed method has been applied to determine zirconium in ore samples, unnecessarily extracted.
Enantioselective Artificial Receptors Formed by the Spreader‐Bar Technique
Authors: Prodromidis Mamas I. , Hirsch Thomas , Mirsky Vladimir M. , Wolfbeis Otto S. 
Published: November 2003

AbstractChiroselective binding sites have been created on thin gold films by application of the spreader‐bar approach. Impedometric techniques and surface plasmon resonance were applied to detect binding. (R)‐(+)‐1,1′‐Binaphthyl‐2,2′‐diol (R‐BNOH) and (S)‐(−)‐1,1′‐binaphthyl‐2,2′‐diol (S‐BNOH) were used as model analytes. The artificial receptors were prepared by co‐adsorption of 16‐mercaptohexadecane (matrix) with a thiol‐modified chiral selector (template). The conjugates of D,L‐thioctic acid and (R)‐(+)‐ or (S)‐(−)‐1,1′‐binaphthyl‐2,2′‐diamine were used as templates. Different concentration ratios of the matrix and template were tested. No chiral selectivity of surfaces formed by either the matrix or the template alone was observed. The use of alkylthiols shorter than 16‐mercaptohexadecane led to the formation of surfaces with no chiral selectivity. The gold electrodes coated by the spreader‐bar technique displayed an enantioselectivity of up to 4.76 or up to 2.55 as measured by the capacitive and SPR methods, respectively.
A comparative study of volatile constituents of two Helichrysum italicum (Roth) Guss. Don Fil subspecies growing in Corsica (France), Tuscany and Sardinia (Italy)
Authors: Bianchini Ange , Tomi Pierre , Bernardini Antoine Francois , Morelli Ivano , Flamini Guido , Cioni Pier Luigi , Usaï Marianna , Marchetti Mauro 
Published: November 2003

AbstractThe essential oils obtained by water distillation from the aerial parts of two Helichrysum italicum ssp. growing in Corsica (France), Tuscany and Sardinia (Italy) were analysed by GC–RI and GC–MS. The essential oils prepared from Corsican and Tuscan Helichrysum italicum subsp. italicum exhibited two different compositions. Corsican oils were characterized by the pre‐eminence of oxygenated compounds: neryl acetate (major compound), neryl propionate, nerol, acyclic ketones and β‐diketones. Conversely, Tuscan oils were found to exhibit higher contents of hydrocarbons (α‐pinene, β‐caryophyllene, α‐ and β‐selinenes). The comparison of essential oils hydrodistilled from Corsican and Sardinian Helichrysum italicum subsp. microphyllum showed almost similar chemical compositions. The main constituents were: neryl acetate, nerol, neryl propionate, linalool, eudesm‐5‐en‐11‐ol and γ‐curcumene. Copyright © 2003 John Wiley & Sons, Ltd.
Composition of the essential oil of Ballota undulata, B. nigra ssp. foetida and B. saxatilis
Authors: Bader Ammar , Caponi Chiara , Cioni Pier Luigi , Flamini Guido , Ivano Morelli  
Published: November 2003

AbstractThe essential oil composition of Ballota nigra ssp. foetida, B. undulata and B. saxatilis, collected during the ﬂowering phase in Amman (Jordan), Naur (Jordan) and Pisa (Italy) respectively, was investigated. The chemical composition of the essential oil of B. nigra and B. undulata shows some similarities: monoterpenes are little represented, while sesquiterpenes are present in large amounts. In both cases germacrene D is the main compound. B. saxatilis essential oil is quite different from B. nigra and B. undulata ones: sesquiterpenes are still the main class of compounds but monoterpenes are much more represented; moreover, in this case the main compound is the oxygenated monoterpene, linalool. Copyright © 2003 John Wiley & Sons, Ltd.
Characteristic odour components of Citrus sp. (Kiyookadaidai) cold‐pressed peel oil
Authors: Minh Tu N. T. , Onishi Y. , Choi H. S. , Kondo Y. , Ukeda H. , Sawamura M. 
Published: November 2003

AbstractThe volatile components of Citrus sp. (Kiyookadaidai) cold‐pressed peel oil were investigated by chemical and sensory analyses. Monoterpene hydrocarbons were abundant, accounting for more than 90.2% of the total content. Myrcene was determined to be the predominant monoterpene hydrocarbon (62.4%), rather than limonene, which is usually reported as most abundant in citrus cold‐pressed oils. The weight percentages of alcohols, aldehydes and esters were >1.0%, >0.8% and >0.8%, respectively. Forty‐seven aroma‐active compounds were detected in Kiyookadaidai oil using GC–O and AEDA. Myrcene, (Z)‐ocimene and α‐bergamotene were the odour‐characteristic compounds, creating a Kiyookadaidai‐like odour. A model solution prepared from one certain con‐centration of myrcene, limonene and (Z)‐ocimene yielded the refreshing and characteristically green aroma of Kiyookadaidai cold‐pressed oil. Copyright © 2003 John Wiley & Sons, Ltd.
Characterization of metabolites and disposition of tertiary amyl methyl ether in male F344 rats following inhalation exposure
Authors: Sumner Susan C. J. , Asgharian Bahman , Moore Timothy A. , Parkinson Horace D. , Bobbitt Carol M. , Fennell Timothy R. 
Published: November 2003

AbstractTertiary amyl methyl ether (TAME) is a fuel additive used to reduce carbon monoxide in automobile emissions. Because of the potential for human exposure, this study was conducted to develop methods for the characterization and quantitation of metabolites in expired air and excreta of rats exposed to a mixture of [13C]‐ and [14C]TAME ([2,3,4‐13C]‐ and [2‐14C]2‐methoxy‐2‐methylbutane). The distribution of TAME in rats was determined following inhalation exposure, and TAME‐derived metabolites were characterized in expired air and urine. Male rats were exposed for 6 h via nose‐only inhalation to 2500 ppm [14C/13C]TAME, and expired air, urine and feces were collected for up to 7 days. Over 95% of the total recovered radioactivity was excreted by 48 h after exposure. Recovered radioactivity was expired as organic volatiles (44%) and 14CO2 (3%) and excreted in urine (51%) and feces (1%). Both TAME and its metabolite tertiary amyl alcohol (TAA) accounted for ≥90% of the radiolabel in expired air 0–8 h following exposure termination. Three major urinary metabolites of TAME were identiﬁed: (1) a direct glucuronide conjugate of TAA; (2) a product of oxidation at the methylene carbon of TAA (2,3‐dihydroxy‐2‐methylbutane); (3) a glucuronide conjugate of metabolite 2. Metabolite 1 accounted for most of the TAME‐derived metabolites excreted 0–8 h following exposure termination. Further metabolic products of TAA (metabolites 2 and 3) accounted for most of the excreted TAME‐derived metabolites at later time points. Copyright © 2003 John Wiley & Sons, Ltd.
Radiosynthesis of [N‐methyl‐11C]methylene blue
Authors: Schweiger Lutz , Craib Stuart , Welch Andrew , Sharp Peter 
Published: November 2003

AbstractIn this paper we present the radiochemical synthesis of the novel compound [N‐methyl‐11C]methylene blue. The synthesis of [N‐methyl‐11C]methylene blue was accomplished by means of 11C‐methylation of commercially available Azure B using [11C]methyl trifluoromethanesulfonate ([11C]methyl triflate). Following purification [N‐methyl‐11C]methylene blue was obtained with a radiochemical purity greater than 97% in a 4–6% decay corrected radiochemical yield. The synthesis was completed in an average of 35 min following the end of bombardment. Copyright © 2003 John Wiley & Sons, Ltd.
Synthesis of NCA [carbonyl‐11C]amides by direct reaction of in situ generated [11C]carboxymagnesium halides with amines under microwave‐enhanced conditions
Authors: Lu Shui‐Yu , Hong Jinsoo , Pike Victor W. 
Published: November 2003

AbstractNo‐carrier‐added (NCA) aromatic and aliphatic [carbonyl‐11C]amides were rapidly (<5 min) synthesized in one pot in useful radiochemical yields (20–65%, decay‐corrected) by directly coupling amines with NCA [11C]carboxyhyphenmagnesium halides generated in situ from Grignard reagents and cyclotron‐produced [11C]carbon dioxide. In this system cyclohexylcarboxymagnesium chloride (1b) is more reactive than 4‐fluorophenylcarboxymagnesium bromide (2b) and primary amines (e.g. aniline, aminopyridines) far more reactive than secondary amines (e.g. 2‐(methylamino)pyridine). The scope of the reaction was widened considerably by the application of microwaves, which allowed reactions to be carried out at much higher temperature than the boiling point of the solvent (i.e. tetrahydrofuran, b.p. 67°C). Copyright © 2003 John Wiley & Sons, Ltd.
Precision of the CASL‐perfusion MRI technique for the measurement of cerebral blood flow in whole brain and vascular territories
Authors: Floyd Thomas F. , Ratcliffe Sarah J. , Wang Jiongjiong , Resch Brooke , Detre John A. 
Published: November 2003

AbstractPurposeTo analyze the precision of cerebral blood flow (CBF) measurements made with continuous arterial spin labeling(CASL) perfusion magnetic resonance imaging (MRI) over experimentally relevant intervals.Materials and MethodsCASL perfusion MRI measurements of CBF on a 1.5‐T GE Signa magnet were repeated in young healthy male and female subjects at one hour and one week. Precision of the measurement was evaluated at both time intervals.ResultsCASL perfusion MRI measurements of CBF yielded within‐subject coefficients of variation (wsCV) of 5.8% for global and 13% for individual vascular regions when measurements were repeated within one hour. Differences in these values represent the error in post‐processing. Global and regional CBF measurements over one week yielded wsCVs of 13% and 14%, respectively. At one week, error secondary to physiologic variability affected global and regional measurements to the same degree and masked the software post‐processing error seen at one hour. The magnitude of the difference in repeated measures correlated with the magnitude of the measurement.ConclusionCASL perfusion MRI CBF measurements are accurate and precise. Variability over longer periods of time appears attributable to physiologic factors. Repeatability of the CASL measurement is sensitive to the magnitude of the measurement. This should be taken into account when studies requiring repeated measures involve subjects with significant variability in CBF. J. Magn. Reson. Imaging 2003;18:649–655. © 2003 Wiley‐Liss, Inc.
MRI for the diagnosis of pulmonary embolism
Authors: van Beek Edwin J.R. , Wild Jim M. , Fink Christian , Moody Alan R. , Kauczor Hans‐Ulrich , Oudkerk Matthijs 
Published: November 2003

AbstractPulmonary embolism (PE) is one of the most frequently encountered clinical emergencies. The diagnosis often involves multiple diagnostic tests, which need to be carried out rapidly to assist in the safe management of the patient. Recent strides in computed tomography (CT) have made big improvements in patient management and efficiency of diagnostic imaging. This review article describes the developments in magnetic resonance (MR) techniques for the diagnosis of acute PE. Techniques include MR angiography (MRA) and thrombus imaging for direct clot visualization, perfusion MR, and combined perfusion‐ventilation MR. As will be demonstrated, some of these techniques are now entering the clinical arena, and it is anticipated that MR imaging (MRI) will have an increasing role in the initial diagnosis and follow‐up of patients with acute PE. J. Magn. Reson. Imaging 2003;18:627–640. © 2003 Wiley‐Liss, Inc.
A New Chemo‐Enzymatic Route to Side‐Chain Liquid‐Crystalline Polymers: The Synthesis and Polymerization of 6‐(4‐Methoxybiphenyl‐4′‐oxy)hexyl Vinyl Hexanedioate
Authors: Hao Xiaojuan , Albertin Luca , Foster L. John R. , Davis Thomas P. , Barner‐Kowollik Christopher 
Published: November 2003

AbstractA novel synthetic method combining chemo and enzymatic synthesis strategies was employed to prepare a vinyl acetate type monomer, 6‐(4‐methoxybiphenyl‐4′‐oxy)hexyl vinyl hexanedioate (VA‐LC). Homo‐ and copolymers of VA‐LC with maleic anhydride (MAn) were prepared by conventional free radical polymerization using 2,2′‐azobisisobutyronitrile (AIBN) and 1,1′‐azobis (cyclohexane carbonitrile) (AHCN) as an initiator at 95 and 60 °C, respectively. The thermal properties of the generated polymeric material were investigated by differential scanning calorimetry (DSC), and the optical texture was inspected by polarizing optical microscopy (POM). While the monomer VA‐LC does not exhibit liquid‐crystalline properties, poly(VA‐LC), and the alternating copolymer of VA‐LC with maleic anhydride both displayed such properties.
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Mellin transforms of p‐adic Whittaker functions
Authors: Deitmar Anton 
Published: November 2003

AbstractIt is shown that Mellin transforms of p‐adic Whittaker functions exist for generic characters. For good choices of vectors they are rational functions. For class one vectors they can be calculated explicitly. It turns out that they are automorphic L‐factors times normalization factors. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
The Strength of the Macromonomer Strategy for Complex Macromolecular Architecture: Molecular Characterization, Properties and Applications of Polymacromonomers
Authors: Hadjichristidis Nikos , Pitsikalis Marinos , Iatrou Hermis , Pispas Stergios 
Published: November 2003

AbstractThe efficiency of the macromonomer (MM) synthetic strategy for the creation of nonlinear complex macromolecular architectures (miktoarm stars, α,ω‐branched polymers, random/exact comb and graft copolymers, dendritic polymers, molecular brushes) is reviewed. In addition, the solution/bulk properties and the potential applications of polymacromonomers (PMM), as well as new synthetic ideas are presented. The synthesis of macromonomers and living polymacromonomers in situ leads to many novel linear and nonlinear structures, as for example PMM‐b‐PS‐b‐PMM, (PS)2PMM. The use of multichlorosilylstyrenes as monomer/linking agents opens new ways for structures with multichain macromonomeric building blocks.The use of multichlorosilylstyrenes as monomer/linking agents opens new ways for structures having multichain macromonomeric building blocks.magnified imageThe use of multichlorosilylstyrenes as monomer/linking agents opens new ways for structures having multichain macromonomeric building blocks.
Impaired heteronymous somatosensory motor cortical inhibition in dystonia
Authors: Bertolasi Laura , Romito Silvia , Tinazzi Michele , Rizzuto Niccoló , Priori Alberto 
Published: November 2003

AbstractA typical pathophysiological abnormality in dystonia is cocontraction of antagonist muscles, with impaired reciprocal inhibitory mechanisms in the spinal cord. Recent experimental data have shown that inhibitory interactions between antagonist muscles have also a parallel control at the level of the sensorimotor cortex. The aim of this work was to study heteronymous effects of a median nerve stimulus on the corticospinal projections to forearm muscles in dystonia. We used the technique of antagonist cortical inhibition, which assesses the conditioning effect of median nerve afferent input on motor evoked potentials (MEPs) elicited by transcranial magnetic stimulation (TMS) in ipsilateral forearm extensor muscles at rest. Nine healthy subjects and 10 patients with torsion dystonia participated in the study. MEPs and somatosensory evoked potentials were normal in patients. In healthy subjects, median nerve stimulation at 15‐ to 18‐msec intervals inhibited the test MEPs in forearm extensors. In dystonic patients, median nerve stimulation delivered at the same conditioning–test intervals elicited significantly less inhibition of the test MEP. On the whole, these data suggest an impaired sensory–motor integration in dystonia and, more specifically, the decreased antagonistic cortical inhibition could suggest that functional interactions between antagonist muscles are primarily impaired at the cortical level. © 2003 Movement Disorder Society
Subthalamic lesion and paroxysmal tonic spasms
Authors: Garcia‐Ruiz Pedro J. , Villanueva Vicente , Gutierrez‐Delicado Eva , Echeverría Amaia , Perez‐Higueras Antonio , Serratosa José M. 
Published: November 2003

AbstractParoxysmal dyskinesia due to a subthalamic lesion is a rare finding. We describe a patient with paroxysmal tonic spasms due to a well‐defined lesion in the subthalamic area. In this case, we confirm the nonepileptic nature of the episode and collect with detail the clinical features by means of a video‐electroencephalographic recording. We also report an excellent response to carbamazepine in subthalamic paroxysmal dyskinesias. © 2003 Movement Disorder Society
Periodic limb movement during sleep developed after pontine lesion
Authors: Kim Joong‐Seok , Lee Sang‐Bong , Park Soung‐Kyeong , Han Si‐Ryung , Kim Yeong‐In , Lee Kwang‐Soo 
Published: November 2003

AbstractWe describe 2 patients who suffered a pontine infarction and subsequently developed periodic leg movement (PLM). The temporal relationship between a stroke and subsequent PLM, as well as the absence of sleep‐related disorders in patients' histories, favors the argument of a cause‐and‐effect relationship, with the observed association providing evidence for an anatomic substrate for PLM. © 2003 Movement Disorder Society
Manic episode with psychotic symptoms induced by subthalamic nucleus stimulation in a patient with Parkinson's disease
Authors: Herzog Jan , Reiff Julia , Krack Paul , Witt Karsten , Schrader Bettina , Müller Dieter , Deuschl Günther 
Published: November 2003

AbstractDeep brain stimulation of the subthalamic nucleus (STN–DBS) is an established therapy for Parkinson's disease (PD). A manic episode with psychotic symptoms induced by STN–DBS occurred in a previously psychiatrically healthy patient, focusing on the role of STN–DBS in influencing not only motor but also emotional behaviour. © 2003 Movement Disorder Society
Adult onset Niemann‐Pick type C disease: A clinical, neuroimaging and molecular genetic study
Authors: Battisti Carla , Tarugi Patrizla , Dotti Maria Teresa , De Stefano Nicola , Vattimo Angelo , Chierichetti Francesea , Calandra Sebastiano , Federico Antonio 
Published: November 2003

AbstractWe report on a patient with adult‐onset Niemann‐Pick type C (NPC) disease, carrying the mutations P1007 and I1061T in the NPC1 gene, presenting with marked psychiatric changes followed by dystonia and cognitive impairment. Filipin staining, single photon emission computed tomography perfusional, positron emission tomography metabolic, conventional magnetic resonance imaging, and magnetic resonance spectroscopy findings suggested a pathophysiological correlation with phenotype expression. This case expands the clinical and genetic spectrum of the rare adult‐onset NPC disease phenotype. © 2003 Movement Disorder Society
Novel antiepileptic drug levetiracetam decreases dyskinesia elicited by L‐dopa and ropinirole in the MPTP‐lesioned marmoset
Authors: Hill Michael P. , Bezard Erwan , McGuire Steven G. , Crossman Alan R. , Brotchie Jonathan M. , Michel Ann , Grimée Renee , Klitgaard Henrik 
Published: November 2003

AbstractLong‐term dopamine replacement therapy of Parkinson's disease leads to the occurrence of dyskinesias. Altered firing patterns of neurons of the internal globus pallidus, involving a pathological synchronization/desynchronization process, may contribute significantly to the genesis of dyskinesia. Levetiracetam, an antiepileptic drug that counteracts neuronal (hyper)synchronization in animal models of epilepsy, was assessed in the MPTP–lesioned marmoset model of Parkinson's disease, after coadministration with (1) levodopa (L‐dopa) or (2) ropinirole/L‐dopa combination. Oral administration of levetiracetam (13–60 mg/kg) in combination with either L‐dopa (12 mg/kg) alone or L‐dopa (8 mg/kg)/ropinirole (1.25 mg/kg) treatments was associated with significantly less dyskinesia, in comparison to L‐dopa monotherapy during the first hour after administration. Thus, new nondopaminergic treatment strategies targeting normalization of abnormal firing patterns in basal ganglia structures may prove useful as an adjunct to reduce dyskinesia induced by dopamine replacement therapy without affecting its antiparkinsonian action. © 2003 Movement Disorder Society
Mesencephalic cryptococcal abscesses presenting with parkinsonism as an initial manifestation of AIDS
Authors: Bouffard John‐Paul , Mena Hernando , Ripple Mary , Troncoso Juan 
Published: November 2003

AbstractParkinsonism has been associated with HIV/AIDS and cerebral cryptococcal disease, but to date there has been no report of histological cryptococcal lesions in the substantia nigra (SN) in a patient with parkinsonism. We report on a case of a 63‐year‐old man who presented with tremor, gait disturbance, and mask‐like facies, and showed cryptococcal meningoencephalitis with cryptococcal abscesses in the SN at autopsy, without Lewy bodies or significant degeneration of the SN neurons. Parkinsonism also represented the first manifestation of AIDS in this previously undiagnosed patient. This case highlights the importance of considering infectious etiologies in patients presenting with parkinsonism, and underscores the need for autopsy in evaluation of patients with new or unexplained movement disorders. Movement disorders in association with AIDS and mesencephalic mass lesions are discussed. © 2003 Movement Disorder Society
Effect of ethanol on the central oscillator in essential tremor
Authors: Zeuner Kirsten E. , Molloy Fiona M. , Shoge Richard O. , Goldstein Susanne R. , Wesley Robert , Hallett Mark 
Published: November 2003

AbstractWe investigated the effects of ethanol and diazepam on the central, mechanical, and mechanical reflex components of tremor in patients with essential tremor (ET). A double‐blind crossover study (ethanol or diazepam) was conducted on 2 separate days. Dose of ethanol or diazepam was calculated in each individual according to height, weight, and age in 10 patients with ET. The postural tremor amplitude at the wrist was recorded using a three‐dimensional accelerometer placed on the dorsum of the hand. Electromyogram (EMG) was recorded with surface electrodes placed on the forearm extensors and flexors. To separate central and mechanical (reflex) components, a 500‐g weight was placed on the dorsum of the hand during a second tremor measurement. Tremor recordings were done at baseline and 30, 60, 90, and 120 minutes after drug ingestion. Ethanol and diazepam blood levels were measured at baseline and after 20, 40, 80, and 120 minutes. Blood ethanol and diazepam levels were highest after 40 and 80 minutes. The amplitude of the central component 60 minutes after ingestion of ethanol was decreased significantly (P = 0.029) compared with diazepam. Our findings suggest that the improvement in tremor after ethanol ingestion was due, at least in part, to an effect on a central oscillator. © 2003 Movement Disorder Society