bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reverse Atom Transfer Radical Polymerization of Methyl Methacrylate using a New Catalyst, Copper(II) N,N′‐Butyldithiocarbamate
Authors: Zhang Wei , Zhu Xiulin , Zhu Jian , Cheng Zhenping 
Published: April 2004

AbstractSummary: The homogeneous bulk reverse ATRP using AIBN/Cu(SC(S)N(C4H9)2)2/bpy as the initiating system has been successfully carried out for methyl methacrylate. Well‐controlled polymerizations with low polydispersities ($\overline M _{\rm w} /\overline M _{\rm n}$ = 1.10–1.30) have been achieved. The revised number‐average molecular weights ($\overline M _{{\rm n}({\rm rev})}$'s) increased linearly with monomer conversion and were close to the $\overline M _{{\rm n}({\rm th})}$ values. The polymerization rate followed the first‐order kinetics in monomer, while it is about 2.0 order in initiator concentration and 1.15 order in Cu(II) concentration. The k values for the homogeneous bulk reverse ATRP of MMA initiated by AIBN/Cu(SC(S)N(C4H9)2)2/bpy (1:2:6) at 80, 90, 100 and 110 °C were 0.402 × 10−4, 1.021 × 10−4, 2.952 × 10−4, and 3.687 × 10−4 (s−1), respectively. On the basis of the Arrhenius plot, the apparent activation energy was calculated to be ΔE = 87.1 kJ/mol. The obtained PMMA was functionalized with an ultraviolet light sensitive ω‐SC(S)N(C4H9)2 group characterized by means of 1H NMR spectroscopy, and which was also proved by its chain extension with fresh MMA under UV‐light irradiation at room temperature. A polymerization mechanism for this novel initiation system is proposed.Dependence of $\overline M _{{\rm n}({\rm rev})}$ and $\overline M _{\rm w} /\overline M _{\rm n}$ on the monomer conversion for the homogeneous bulk reverse ATRP of MMA at different concentration of catalyst.magnified imageDependence of $\overline M _{{\rm n}({\rm rev})}$ and $\overline M _{\rm w} /\overline M _{\rm n}$ on the monomer conversion for the homogeneous bulk reverse ATRP of MMA at different concentration of catalyst.
Novel Polyelectrolyte Carboxymethyl Konjac Glucomannan–Chitosan Nanoparticles for Drug Delivery
Authors: Du Jian , Sun Rui , Zhang Sheng , Govender Thirumala , Zhang Li‐Fang , Xiong Cheng‐Dong , Peng Yu‐Xing 
Published: April 2004

AbstractSummary: Carboxymethyl Konjac Glucomannan–Chitosan (CKGM‐CS) nanoparticles, which are well dispersed and stable in aqueous solution, were spontaneously prepared under very mild conditions by polyelectrolyte complexation. Investigations of the physicochemical properties of these nanoparticles were undertaken. This study showed that the nanoparticulate system driven by complex formation has potential as an advanced drug‐delivery system for water‐soluble drugs.Preparation mechanism of CS–CKGM nanoparticles.imagePreparation mechanism of CS–CKGM nanoparticles.
Thermosensitive PEGylated Polypeptides
Authors: Cho Jang Young , Sohn Youn Soo , Gutowska Anna , Jeong Byeongmoon 
Published: April 2004

AbstractSummary: We report a thermosensitive polypeptide consisting of hydrophilic poly(ethylene glycol)s and hydrophobic phenyl alanine ethyl esters. It is soluble in most solvents and undergoes a micelle (radius ≈ 10 nm) to nanoparticle (radius ≈ 100 nm) transition in water as the temperature increases. The transition temperature could be controlled to between 30 and 40 °C by varying the number of poly(ethylene glycol) grafts. This system might be promising for advanced drug delivery.Measurement of the lower critical solution temperatures of PEG‐PP aqueous solutions (1.0 wt.‐%).imageMeasurement of the lower critical solution temperatures of PEG‐PP aqueous solutions (1.0 wt.‐%).
Nanostructured Crosslinkable Micropatterns by Amphiphilic Dendrimer Stamping
Authors: Kohli Neeraj , Dvornic Petar R. , Kaganove Steven N. , Worden Robert M. , Lee Ilsoon 
Published: April 2004

AbstractSummary: Microcontact printing was used to deposit stable, nanostructured, amphiphilic and crosslinkable patterns of poly(amidoamine organosilicon) (PAMAMOS)‐dimethoxymethylsilyl (DMOMS) dendrimer multilayers onto silicon wafers, glass, and polyelectrolyte multilayers. The effects of dendrimer ink concentration, contact time, and inking method, on the thickness, uniformity, and stability of the resulting patterns were studied using optical microscopy, fluorescence microscopy, atomic force microscopy (AFM), and contact‐angle analysis. Microarrayed dendrimer film thickness was found to be controllable by conditions used during spin self‐assembly.Optical micrograph of the circular patterns, obtained from a 0.5% PAMAMOS dendrimer solution, on a glass substrate.imageOptical micrograph of the circular patterns, obtained from a 0.5% PAMAMOS dendrimer solution, on a glass substrate.
Transient blepharospasm secondary to unilateral striatal infarction
Authors: Grandas Francisco , López‐Manzanares Lydia , Traba Alfredo 
Published: April 2004

AbstractWe report on a patient who presented a transient eyelid motor disorder characterized by bilateral reflex blepharospasm as the main clinical manifestation of a right‐sided striatal infarction. This case emphasizes the role of the nondominant striatum in the pathophysiology of eyelid motor abnormalities. © 2004 Movement Disorder Society
Anxiety in musicians with focal dystonia and those with chronic pain
Authors: Jabusch Hans‐Christian , Müller Sandra V. , Altenmüller Eckart 
Published: April 2004

AbstractPsychological conditions were studied in 20 musicians with focal dystonia and compared with 20 musicians with chronic pain and 30 healthy musicians using the Freiburg Personality Inventory and the Questionnaire for Competence and Control Orientations. Additional questionnaires focused on perfectionism and anxiety particularly with regard to the dynamics of these psychological features. Musicians with focal dystonia and those with chronic pain more often displayed anxiety than controls. In both patient groups, anxiety was present before onset of the playing‐related disorder. Dystonic musicians additionally showed higher levels of perfectionism than controls, which was not observed in musicians with chronic pain. © 2004 Movement Disorder Society
Elucidation of the structures of 3‐alkylthio‐, 3‐benzylthio‐, 2‐arylthio‐ and 2‐heteroarylthio‐N1‐(1,3‐dimethylbutyl)‐N4‐phenyl‐1,4‐phenylenediamines by one‐ and two‐dimensional NMR spectroscopy
Authors: Katritzky Alan R. , Akhmedov Novruz G. , Abdel‐Fattah Ashraf A. A. , Wang Mingyi , Rostek Charles J. , Maender Otto W. 
Published: April 2004

AbstractNucleophilic addition of alkyl‐ and benzylthiols to benzoquinone diimine (1) gave the corresponding 3‐alkylthio‐ or 3‐benzylthio‐1,4‐phenylenediamines (2–5). However, addition of aryl‐ or heteroarylthiols to 1 formed 2‐arylthio‐ or 2‐heteroarylthio‐1,4‐phenylenediamines (6–14). The structures of 2–14, obtained in 55–91% yields, were confirmed in CDCl3 or DMSO‐d6 solution using 1D (NOE difference, coupled 13C NMR spectra, APT and DEPT) and 2D NMR techniques [DQCOSY, NOESY, HETCOR and heteronuclear multiple bond coherence (HMBC)] that resulted in unambiguous proton and carbon NMR resonance assignments. The substituent‐induced 13C NMR chemical shift differences were calculated in 2–14 relative to carbon atoms in the model compound N1‐(1,3‐dimethylbutyl)‐N4‐phenyl‐1,4‐phenylenediamine (DMBPPD) (15) (a reduced form of benzoquinone diimine). Copyright © 2004 John Wiley & Sons, Ltd.
NMR and x‐ray conformational study of artemisiifolin and three other related germacranolides
Authors: Jimeno María L. , Apreda‐Rojas María del Carmen , Cano Félix H. , Rodríguez Benjamín 
Published: April 2004

AbstractFrom an acetone extract of Staehelina dubia, large quantities of the previously known germacranolide artemisiifolin were isolated. The conformations of the 10‐membered germacra‐1(10)E,4Z‐diene ring system of this compound and those of its derivatives 11,13‐dihydroartemisiifolin, isabelin and 6α‐hydroxy‐15‐oxogermacra‐1(10)E,4Z,11(13)‐trien‐12,8α‐olide were studied by NMR spectroscopic methods. Low‐energy conformations were obtained by quantum mechanical calculations. An x‐ray diffraction analysis of artemisiifolin established that, in the crystalline state, it possesses a unique conformation that corresponds to the majority one existing in acetone‐d6 solution. Copyright © 2004 John Wiley & Sons, Ltd.
Combined ab initio computational and experimental multinuclear solid‐state magnetic resonance study of phenylphosphonic acid
Authors: Gervais Christel , Profeta Mickaël , Lafond Vincent , Bonhomme Christian , Azaïs Thierry , Mutin Hubert , Pickard Chris J. , Mauri Francesco , Babonneau Florence 
Published: April 2004

Abstract1H, 13C, 17O and 31P NMR parameters, including chemical shift tensors and quadrupolar parameters for 17O, were calculated for phenylphosphonic acid, C6H5PO(OH)2, under periodic boundary conditions. The results are in very good agreement with experimental data and permit the unambiguous assignment of all the sites present in the structure. In particular, the 17O NMR parameters of the PO and P—OH environments were precisely determined, which should help in the characterization of the bonding mode of phosphonate molecules in hybrid solids. Moreover, the effect of intermolecular interactions on the NMR parameters were investigated by comparing the results of the calculations in the crystal and in an isolated molecule of phenylphosphonic acid. Copyright © 2004 John Wiley & Sons, Ltd.
1H chemical shifts in NMR. Part 20 — Anisotropic and steric effects in halogen substituent chemical shifts (SCS), a modelling and ab initio investigation
Authors: Abraham Raymond J. , Mobli Mehdi , Smith Richard J. 
Published: April 2004

AbstractThe 1H NMR spectra of 1‐halonaphthalenes were recorded and assigned. These data together with the known 1H chemical shifts of the halobenzenes and of H‐5 in 4‐halophenanthrenes were used to investigate different models of halogen SCS using the CHARGE program. Good agreement was obtained with the observed shifts for the fluoro compounds, but a new model which included the anisotropy of the C—X bond (X = Cl, Br, I) and steric and electric field effects was required to give an accurate description of the observed chemical shifts for the other halogens. A previous observation of an anomalous 1H SCS on the meta protons in halobenzenes was further investigated using the 1‐halonaphthalenes plus the observed 1H shifts of a number of 2‐substituted bromobenzenes. The meta SCS of the bromo substituent in the bromobenzenes was only observed on H‐5. When a substituent was attached to C‐2, H‐3 showed no appreciable effect. This remarkable effect was investigated by CHARGE and GIAO calculations and shown to be due to the π‐electron system. It was reproduced in CHARGE as a γ effect from the C—X carbon atom. The observed 1H chemical shifts in the above compounds were compared with those calculated by CHARGE, the GIAO technique and by the ACD database program. The recommended ab initio basis set for the iodo compounds (Lan12DZ) gave very poor calculated shifts, which suggests that 1H chemical shifts of fourth‐row atoms when calculated with the GIAO technique should be viewed with caution. In contrast, the recommended 6–31G** basis set with the B3LYP technique in the Gaussian98 program gave calculated values in reasonable agreement with the observed data, as did the ACD package. These different prediction methods were compared by pie charts, scatter plots and r.m.s. errors and the CHARGE program was shown to be more accurate for the compounds considered here than the other two methods. The different philosophies of these programs are discussed together with the results obtained. Copyright © 2004 John Wiley & Sons, Ltd.
Softening, localization and stabilization: capture of discontinuous solutions in J2 plasticity
Authors: Cervera M. , Chiumenti M. , Agelet de Saracibar C. 
Published: April 2004

AbstractThis paper exploits the concept of stabilization techniques to improve the behaviour of mixed linear/linear simplicial elements (triangles and tetrahedra) in incompressible or nearly incompressible situations. Elasto‐J2‐plastic constitutive behaviour has been considered with linear and exponential softening. Two different stabilization methods are used to attain global stability of the corresponding discrete finite element formulation. Implementation and computational aspects are also discussed, showing that a robust application of the proposed formulation is feasible. Numerical examples show that the formulation derived is free of volumetric locking and spurious oscillations of the pressure. The results obtained do not suffer from spurious mesh‐size or mesh‐bias dependence, comparing very favourably with those obtained with the standard, non‐stabilized, approaches. Copyright © 2004 John Wiley & Sons, Ltd.
Differential responsiveness among “high risk” pediatric brain tumors in a pilot study of dose‐intensive induction chemotherapy
Authors: Jennings Mark T. , Cmelak Anthony , Johnson Mahlon D. , Moots Paul L. , Pais Ray , Shyr Yu 
Published: April 2004

AbstractBackgroundThese factors have been predictive for progressive disease on therapy (PDOT) among pediatric brain tumors: >1.5 cm2 unresectable tumor, glioblastoma, supratentorial primitive neuroectodermal tumor, and metastatic medulloblastoma (MBL). This pilot study sought to correlate cytoreductive response with progression free survival.ProceduresFour courses of cisplatinum, cyclophosphamide, etoposide, and vincristine preceded hyperfractionated radiotherapy (RT). Maintenance chemotherapy consisted of eight cycles of carboplatin, etoposide, and vincristine. Biopsy specimens were immunohistochemically studied for labeling index, hypoxia, and multidrug resistance proteins.ResultsTwenty newly diagnosed patients [nine primitive neuroectodermal tumors/MBL, one choroid plexus carcinoma, eight malignant gliomas, and two anaplastic ependymomas] were treated. Ten patients, who required neuraxis irradiation, constituted the “PNET” group. These demonstrated five complete and one partial response (PR), with an estimated median progression free survival of 44 months and median survival in excess of 53 months. Patients treated with involved field irradiation were designated the “Glioma” group. Induction chemotherapy produced partial and minor responses (MRs) among 5/10. Their estimated median progression free survival was 6.9 months (P = 0.035 relative to the PNET) with a median survival of 10.7 months (P = 0.04). Age, labeling index, the presence of hypoxia, and Pgp/MDR1 expression failed to discriminate between the two groups.ConclusionsThis induction regimen produced a cytoreductive response in 6/10 and achieved a significant improvement in progression free survival among 7/10 in the PNET group. Unfortunately, responses among Glioma patients did not translate into durable control. Expression of the biologic factors was similar between both groups and did not correlate with diagnosis or response. © 2004 Wiley‐Liss, Inc.
Congenital tuberculosis requiring extracorporeal membrane oxygenation
Authors: Weisoly David L. , Khan Amir M. , Elidemir Okan , Smith Kim Connelly 
Published: April 2004

AbstractWe describe a 6‐week‐old infant with congenital tuberculosis with cardiorespiratory failure. She was successfully treated with ECMO initiated after worsening hypoxemia despite mechanical ventilation. Pediatr Pulmonol. 2004; 37:470–473. © 2004 Wiely‐Liss, Inc.
Symptomatic spontaneous pneumothorax in term newborn infants
Authors: Al Tawil Khalil , Abu‐Ekteish Faisal M. , Tamimi Omar , Al Hathal Muneef M. , Al Hathlol Khalid , Abu Laimun Bdeir 
Published: April 2004

AbstractThe association between congenital major urinary tract anomalies (CMUTA) and spontaneous pneumothorax in term newborn infants (SPTNI) is controversial. We conducted a case‐control study to test the hypothesis that SPTNI is associated with CMUTA. We compared 80 term infants with spontaneous pneumothorax to 80 healthy control infants. We recorded risk factors, clinical course, therapy, and outcome. Only 1 infant of 60 infants (1.7%) had CMUTA with SPTNI, as revealed by renal ultrasound studies. This is comparable to the 1.4% rate reported for CMUTA in healthy newborn infants by Steinhart et al. ([1988] Pediatrics 82:609–614). SPTNI were significantly more likely in males with higher birth weights and with vacuum delivery. Sixty‐seven (84%) infants with SPTNI had follow‐up for a mean and median of 46.4 and 39 months, respectively (range, 1–126 months), without manifesting any renal or pulmonary complications. Pediatr Pulmonol. 2004; 37:443–446. © 2004 Wiely‐Liss, Inc.
Standardized procedure for measurement of nasal potential difference: An outcome measure in multicenter cystic fibrosis clinical trials
Authors: Standaert Thomas A. , Boitano Louis , Emerson Julia , Milgram Laura J.H. , Konstan Michael W. , Hunter Janice , Berclaz Pierre‐Yves , Brass Lois , Zeitlin Pamela L. , Hammond Keith , Davies Zoe , Foy Carla , Noone Peadar G. , Knowles Michael R. 
Published: April 2004

AbstractPatients with cystic fibrosis (CF) can be discriminated from healthy subjects by measurement of the nasal potential difference, which has become a useful outcome measure for therapies directed toward correcting defective electrolyte transport in CF. A standard operating procedure was developed by a CF Foundation clinical trials network, to be followed by all sites performing collaborative studies. Key variables in the measurement included type of voltmeter, exploring probe, reference electrodes, and solutions used to assess both sodium transport and chloride conductance. Eight sites submitted data on 3–8 normal and 4–5 CF subjects. Baseline voltage, an index of sodium transport, was −18.2 ± 8.3 mV (mean ± SD) for normals, and −45.3 ± 11.4 mV for CF patients. There was no CFTR‐mediated chloride secretion in CF subjects, as evidenced by the lack of response to perfusion with zero chloride + beta agonist solutions (+3.2 ± 3.5 mV) vs. that in normals (−23.7 ± 10.2 mV). The standardized nasal potential difference measurement minimizes variability between operators and study sites. Valid and consistent results can be attained with trained operators and attention to technical details. These data demonstrate the procedure to be sufficient for multicenter studies in the CF Foundation network. Pediatr Pulmonol. 2004; 37:385–392. © 2004 Wiely‐Liss, Inc.
Asthma prevalence in European, Maori, and Pacific children in New Zealand: ISAAC study
Authors: Pattemore Philip K. , Ellison‐Loschmann Lis , Asher M. Innes , Barry David M.J. , Clayton Tadd O. , Crane Julian , D'Souza Wendyl J. , Ellwood Philippa , Ford Rodney P.K. , Mackay Richard J. , Mitchell Edwin A. , Moyes Christoper , Pearce Neil , Stewart Alistair W. 
Published: April 2004

AbstractThe International Study of Asthma and Allergies in Childhood (ISAAC) demonstrated that the highest prevalence of asthma in the world is in English‐speaking countries, including New Zealand. In this paper, we compare asthma symptom prevalence in the three major ethnic groups (Maori, Pacific, and European) in the six participating centers in New Zealand. Hospital admission rates for asthma are higher among Maori and Pacific children compared to European children. The working hypothesis was that there were important differences in prevalence of asthma symptoms or diagnosis between ethnic groups which might explain these observed differences in asthma morbidity. In each center in 1992–1993, we sampled approximately 3,000 children at each of the age brackets 6–7 years and 13–14 years. There were 37,592 participants. Maori children had higher rates of diagnosed asthma and reported asthma symptoms than Pacific children in both age groups (diagnosed asthma in 6–7‐year‐olds: Maori, 31.7%; Pacific, 21.2%; 95% confidence interval on difference (CID), 7.2, 13.8; P < 0.001; 13–14‐year‐olds: Maori, 24.7%; Pacific, 19.2%; CID 2.5, 8.5; P < 0.001; recent wheeze in 6–7‐year‐olds: Maori, 27.6%; Pacific, 22.0%; CID, 2.6, 8.6; P < 0.001; 13–14‐year‐olds: Maori, 30.8%; Pacific, 21.1%; CID, 4.8, 14.5; P < 0.001;). European children had rates intermediate between those of Maori and Pacific children (6–7‐year‐olds) or similar to those of Maori children (13–14‐year‐olds), but had the lowest prevalence of night waking with wheeze in both age groups (e.g., 6–7‐year‐olds: European, 2.6%; Maori, 5.8%; Pacific, 5.7%; European‐Maori CID: −4.2, −2.2, P < 0.001; European‐Pacific CID: −4.7, −1.7, P < 0.001; Maori‐Pacific CID: −1.7, 1.8, P = 1.0). The pattern of differences closely resembled that in a 1985 Auckland study, despite a 1.5–1.7‐fold overall increase in prevalence. In conclusion, there are important differences in asthma prevalence among Maori, Pacific, and European children. These differences are small compared to worldwide variation, but their pattern is stable over time. The higher rate of severe asthma symptoms that Maori and Pacific children report may be one reason for the increased asthma morbidity in these groups. Further studies are needed to determine the reasons for these apparent differences in asthma severity. Pediatr Pulmonol. 2004; 37:433–442. © 2004 Wiely‐Liss, Inc.
Antibody response to Pseudomonas aeruginosa in cystic fibrosis patients: A marker of therapeutic success?—A 30‐year Cohort study of survival in Danish CF patients after onset of chronic P. aeruginosa lung infection
Authors: Johansen Helle Krogh , Nørregaard Lena , Gøtzsche Peter C. , Pressler Tacjana , Koch Christian , Høiby Niels 
Published: April 2004

AbstractWe studied the effects of increasingly intensive treatment regimens on anti‐pseudomonal antibody response and survival in five successive cohorts of a total of 157 Danish cystic fibrosis patients after they had acquired chronic P. aeruginosa lung infection. The time periods were 1971–1975 (N = 21), 1976–1980 (N = 64), 1981–1986 (N = 27), 1987–1993 (N = 26), and 1994–2000 (N = 19). During this 30‐year period, we introduced elective 2‐week courses of chemotherapy every third month in all chronically infected patients, early aggressive treatment with inhalation of colistin and oral ciprofloxacin for 3 months whenever P. aeruginosa was cultured in sputum from noncolonized patients, and inhalation of recombinant human dornase alfa. There was a significant correlation between the calendar year when chronic P. aeruginosa infection was acquired and the subsequent increase in the level of precipitins (P < 0.00001). The median number of precipitins increased by 5 per year in the oldest calendar year cohort, and 1 per year in the youngest. The median age of onset of chronic P. aeruginosa increased from 9.3 years from 1981–1986 to 13.8 years from 1987–2000. Survival after acquisition of chronic P. aeruginosa lung infection improved with time (P = 0.008). Our study shows that CF patients who are treated intensively have lower antibody responses and longer survival after acquisition of chronic P. aeruginosa lung infection. Pediatr Pulmonol. 2004; 37:427–432. © 2004 Wiely‐Liss, Inc.