bluuebunny/crossref_metadata_2025_split huggingface dataset:
Spreading depolarizations occur in human ischemic stroke with high incidence
Authors: Dohmen Christian , Sakowitz Oliver W. , Fabricius Martin , Bosche Bert , Reithmeier Thomas , Ernestus Ralf‐Ingo , Brinker Gerrit , Dreier Jens P. , Woitzik Johannes , Strong Anthony J. , Graf Rudolf 
Published: May 2008

AbstractObjectiveCortical spreading depression (CSD) and periinfarct depolarization (PID) have been shown in various experimental models of stroke to cause secondary neuronal damage and infarct expansion. For decades it has been questioned whether CSD or PID occur in human ischemic stroke. Here, we describe CSD and PID in patients with malignant middle cerebral artery infarction detected by subdural electrocorticography (ECoG).MethodsCentres of the Co‐operative Study of Brain Injury Depolarisations (COSBID) recruited 16 patients with large middle cerebral artery infarction. During surgery for decompressive hemicraniectomy, an electrode strip was placed on the periinfarct region, from which four ECoG channels were acquired.ResultsA total of 1,638 hours was recorded; mean monitoring time per patient was 109.2 hours. A total of 127 CSD and 42 PID events were observed. In CSD, a stereotyped slow potential change spreading between adjacent channels was accompanied by transient depression of ECoG activity. In PID, a slow potential change spread between neighboring channels despite already established suppression of ECoG activity. Most CSDs and PIDs appeared repetitively in clusters. CSD or PID was observed in all but two patients. In these two patients, the electrode strip had been placed over infarcted tissue, and accordingly, no local ECoG or recurrent transient depolarization activity occurred throughout the observation period.InterpretationCSD and PID occurred spontaneously with high frequency in this study of patients with malignant middle cerebral artery infarction. This suggests that the large volume of experimental studies of occlusive stroke that implicate spreading depolarizations in its pathophysiology can be translated, with appropriate caution, to patients and their treatment. Ann Neurol 2008
Treatment of childhood arterial ischemic stroke
Authors: Bernard Timothy J. , Goldenberg Neil A. , Armstrong‐Wells Jennifer , Amlie‐Lefond Catherine , Fullerton Heather J. 
Published: May 2008

AbstractTraditional risk factors associated with adult arterial ischemic stroke (AIS; ie, hypertension, hyperlipidemia, diabetes, smoking, and atherosclerosis) are relatively rare in children. Childhood AIS is instead associated with a variety of conditions including cerebral arteriopathies, congenital heart disease, infection, head and neck trauma, sickle cell anemia, and prothrombotic abnormalities. Although the pathophysiology and outcomes of adult AIS differ significantly from those in childhood AIS, therapeutic management remains similar, largely because of the paucity of evidence from devoted pediatric observational studies and clinical trials. The purpose of this article is to review the current guidelines and evidence in the treatment of childhood AIS, within the context of that which exists in adult AIS. Medical management of hypoxia, hyperglycemia, fever, blood pressure, and increased intracranial pressure has been insufficiently investigated in childhood stroke, resulting in a lack of guidance in these areas. Although acute antithrombotic management in childhood AIS has received relatively greater attention in published recommendations, it is based almost exclusively on consensus and expert opinion, and differs considerably among existing pediatric guidelines. Rehabilitation therapy in childhood AIS has great potential for meaningful improvements in long‐term outcomes, especially given the plasticity of the young brain; however, little guidance for rehabilitative measures is provided by published recommendations. Ongoing and future multicenter cohort study efforts, and ultimately devoted pediatric clinical trials, will be essential to establish comprehensive evidence‐based guidelines for the treatment of childhood AIS. Ann Neurol 2008
Influence of m‐isopropenyl‐α,α‐dimethylbenzyl isocyanate grafted polypropylene on the interfacial interaction of wood‐flour/polypropylene composites
Authors: Guo Chui Gen , Wang Qing Wen 
Published: May 2008

AbstractIn this article, the effects of m‐isopropenyl‐α,α‐dimethylbenzyl isocyanate grafted polypropylene (m‐TMI‐PP) on the interfacial interaction of wood‐flour/polypropylene (WF/PP) were investigated by means of scanning electron microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetry, dynamic rheological analysis, and mechanical properties tests. The experimental results demonstrated that m‐TMI‐PP greatly improved the interfacial interaction between WF and PP. According to the DSC results, m‐TMI‐PP made the crystallization temperature and the crystallization degree of PP in WF/m‐TMI‐PP/PP decrease when compared with WF/PP composite without m‐TMI‐PP, but it was still higher than pure PP. These results demonstrated that WF presented the nucleate effect for the crystallization of PP and m‐TMI‐PP improved the interfacial adhesive, which restrained the mobility of PP chain. The rheological analysis indicated that the complex viscosity, storage, and loss modular of WF/PP composite increased, and the tan δ decreased with the addition of m‐TMI‐PP. This was attributed to the strong improvement effects of m‐TMI‐PP on the interfacial interaction of the composites, and was further confirmed by the mechanical properties tests and SEM analysis of the composites. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Mechanical damage to estabragh fibers in the production of thermobonded layers
Authors: Gharehaghaji Ali Akbar , Davoodi Sara Hayat 
Published: May 2008

AbstractEstabragh (Asclepias procerais) fibers are natural, hollow fibers, and the mechanical behavior of these fibers plays a major role in mechanical processing. This work explores the mechanical behavior of estabragh fibers in three different areas—tensile failure, carding behavior, and the construction of nonwoven layers—and reports the main barriers in the spinning process of these fibers. In the first step, a typical stress–strain curve of estabragh fibers is plotted. Fractography of the broken ends by scanning electron microscopy shows the granular nature of the fracture. The likely mechanism of tensile failure is discussed and compared with the fracture of cotton fibers under tensile loading. In the second stage, the carding behavior and likely mechanism of fiber damage during the carding process of estabragh fibers are studied. Both qualitative and quantitative studies show that estabragh fibers experience serious damage during the carding process. The effect of the hollowness of the fibers on their mechanical properties is discussed as well. In the final approach, thermobonded layers of two different blends of estabragh fibers and bicomponent poly(ethylene terephthalate) fibers are produced. Some properties of the produced layers, including moisture absorption, ultraviolet absorption, and bending length, are reported. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Phase behavior and self‐assembly of poly[N‐vinylformamide‐co‐(acrylic acid)] copolymers under highly acidic conditions
Authors: Chen Qiang , Liu Xiaoguang , Xu Kun , Song Chunlei , Zhang Wende , Wang Pixin 
Published: May 2008

AbstractCopolymers of N‐vinylformamide and acrylic acid were synthesized by conventional aqueous free‐radical polymerization. The phase behavior of the copolymer solutions was investigated through the addition of hydrochloric acid and the variation of the temperature. With a moderate content of N‐vinylformamide, the copolymers showed complex phase behaviors. Under low‐acidity conditions, a suspending liquid was formed, whereas under high‐acidity conditions, the random copolymers could assemble into round nanoparticles with a broad particle size distribution. When the temperature was reduced, a much less cloudy solution that contained nanoparticles became a milk‐like suspending liquid, and this temperature‐responsive phenomenon was reversible. This indicated that the formamide group was protonated under highly acidic conditions; the repulsive electrostatic forces compelled the aggregates to disperse. The amount of salt and excess acid influenced the particle size as well as the temperature‐responsive behavior of the copolymers under highly acidic conditions. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Preparation and characterization of blends containing natural and some synthetic rubbers with synthesized aromatic polyester
Authors: El‐Sabbagh S. H. , Tawfik M. E. , Helaly F. M. 
Published: May 2008

AbstractThis work deals with the synthesis of aromatic polyester (AP) from polyarylate [Bisphenol A (BPA)/dimethyl terephalate (DMT)/ethylene glycol (EG)] and maleic anhydride (MA) in presence of dibutyl tin oxide (DBTO) as a catalyst. Blends were prepared from candidated AP (10–30 phr) with different types of rubber [natural rubber (NR), acrylonitrile butadiene rubber (NBR), styrene butadiene rubber (SBR) and ethylene‐propylene‐diene monomer (EPDM)]. The obtained blends were subjected to physicomechanical measurements to evaluate their properties as efficient blends for economic industrial applications. In case of AP blended with rubber, better properties were obtained than that of rubber vulcanizates. The fatigue life values decreases by increasing the AP contents for all types of the tested blends. The equilibrium swelling (%) for the prepared blends exhibits different behavior in solvents like toluene and motor oil. The addition of N‐isopropyl‐N′‐phenyl‐p‐phenylene diamine (IPPD), as antioxidant, affects the properties of all the prepared products. These properties were in consequent with the data of the initial shear modulus, which is calculated from the Mooney‐Rivlin equation and the percentage of the equilibrium swelling. Scanning electron microscope (SEM) was used to study the morphological structure; the SEM results show the changes in surface of the rubber before and after being blended with AP. The investigated blends are considered a new trend in giving products with variable physicomechanical characteristics. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Structural changes of regenerated cellulose dissolved in FeTNa, NaOH/thiourea, and NMMO systems
Authors: El‐Wakil Nahla A. , Hassan Mohammad L. 
Published: May 2008

AbstractRegenerated cellulose was prepared from microcrystalline cellulose (MCC) via dissolution in three well‐known nonderivatizing systems: ferric chloride/sodium tartarate/sodium hydroxide (FeTNa), sodium hydroxide/thiourea (NaOH/thiourea), and N‐methylmorpholine‐N‐oxide (NMMO) systems. The effect of regeneration using the different systems on the supramolecular structure of the regenerated celluloses was studied using X‐ray diffraction and Fourier transform infrared (FTIR). The effect of regeneration on supermolecular structure, morphology, and thermal stability of regenerated celluloses were studied using scanning electron microscopy (SEM) and thermogravimetric analysis (TGA). The effect of regeneration systems used on the chemical reactivity of cellulose toward carboxymethylation, acetylation, and cyanoethylation reactions was briefly studied. The results showed dependence of all the aforementioned properties on the dissolution reagent used in spite of that all studied reagents cause the same change in cellulose crystalline structure (from cellulose I to cellulose II). The degree of polymerization, crystallinity, and thermal stability of the regenerated cellulose (RC) samples were in the following order: NaOH/thiourea RC > FeTNa RC > NMMO RC. SEM micrograph showed unique surface for the NMMO RC sample. The reactivity of the different regenerated cellulose samples toward carboxymethylation, cyanoethylation, and acetylation depended mainly on the reaction system and conditions used rather than on crystallinity of regenerated cellulose. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Quercetin microspheres by solvent evaporation: Preparation, characterization and release behavior
Authors: Scarfato Paola , Avallone Elvira , Iannelli Pio , Aquino Rita P. , Lauro Maria Rosaria , Rossi Alessandra , Acierno Domenico 
Published: May 2008

AbstractQuercetin (Q) gastro‐resistant microspheres were successfully prepared by solvent evaporation method using cellulose acetate phthalate (C‐A‐P), cellulose acetate propionate (CAP), or their mixtures in different ratios as matrices. The formulation and preparation conditions (stirring speed, polymer concentration, drug‐to‐polymer ratio, temperature) were optimized to obtain high encapsulation efficiency and production yield. The prepared microspheres were submitted to several chemical–physical analyses (light scattering, fluorescence and scanning electron microscopy, X‐ray diffractometry, calorimetry, infrared spectroscopy), to obtain information about particle size distribution, drug loading, and morphology. Moreover, their release properties were investigated performing in vitro dissolution studies with a pH change method. The release tests evidenced that all samples exhibit a fairly gastro‐resistance with a typical biphasic drug release trend, due to the pH‐dependent solubility of the enteric polymers used as matrices. Moreover, the total amount of released quercetin strictly depends on the system composition, increasing with the C‐A‐P percentage in the formulation to such an extent that it is about complete (∼ 90%) in the case of C‐A‐P microspheres. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Synthesis and characterization of ferromagnetic polyaniline with conductivity in an applied magnetic field
Authors: Zhang Ya , Zhu Chunxia , Kan Jinqing 
Published: May 2008

AbstractFerromagnetic polyaniline (PANI) with conductivity was synthesized with peroxydisulfate as an oxidant and horseradish peroxidase as a catalyst in anN′‐a‐hydroxythylpiperazine‐N′‐ethanesulfanic acid buffer solution containing aniline, HCl, and NiCl2·6H2O in an applied magnetic field. The result of an electron paramagnetic resonance spectrum indicated that there were unpaired electrons in the resulting product, the spin density of which was 7.60 × 1019spins/g. The curve of the magnetization versus the magnetic field showed that PANI had soft ferromagnetic behavior at about 300 K. The saturation magnetization and coercive force of PANI were 0.033 emu/g and 5 Oe, respectively. Ultraviolet–visible and Fourier transform infrared spectra indicated that there was interaction between Ni2+and PANI chains but the structure of the backbone chains of PANI synthesized in the presence of a magnetic field hardly changed compared with that of PANI synthesized without NiCl2·6H2O. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008
Assessment of the ecological status of north‐eastern Adriatic coastal waters (Istria, Croatia) using macroalgal assemblages for the European Union Water Framework Directive
Authors: Iveša Ljiljana , Lyons Daniel Mark , Devescovi Massimo 
Published: May 2008

Abstract
Based on the inclusion of macroalgae in the European Union Water Framework Directive as quality elements for the evaluation of the ecological status of coastal waters, the suitability of one (Ecological Evaluation Index, EEI) of several previously proposed evaluation methods in the particular ecological conditions of the northern Adriatic Sea was tested.
The EEI was assessed for 10 locations (polluted and putatively pristine) scattered along 60 km of the western Istrian coast. The sampling was performed seasonally at 1 and 3 m depth by destructive (determination of species cover and biomass) and non‐destructive (determination of species coverage using digital photography) methods.
When assessed at 1 m depth the spatial scale weighted EEI for the west Istrian coast was 8.1, corresponding to an ecological status class (ESC) value of high. However, data for 3 m depth gave a spatial EEI of 6.72 which corresponds to an ESC value of good. Regressions of the ratio of ecological state group I (ESG I, i.e. thick leathery, calcareous and crustose species) over total algal abundance with the pollution gradient (obtained using principal components analysis (PCA) ordination of environmental variables) were significant at 3 m but not at 1 m depth. This was due to the high abundance of ESG I macroalgae Corallina elongata and Cystoseira compressa at 1 m depth at polluted stations. Similar regressions were obtained using cover, biomass and coverage.
It is concluded that the EEI method may be suitable for the classification of coastal waters in the northern Adriatic only in certain cases. A better assessment of ecological status using this method would require more realistic estimations based on the inclusion of data from several sampling depths. As all three abundance measures (cover, biomass, coverage) gave similar results, coverage (using digital photography) is suggested as being a preferred measure owing to the rapidity of sampling at several depths and less time‐consuming laboratory work.
Copyright © 2008 John Wiley & Sons, Ltd.
The influence of the broadness of a query of a topic on its h‐index: Models and examples of the h‐index of n‐grams
Authors: Egghe Leo , Ravichandra Rao I.K. 
Published: May 2008

AbstractThe article studies the influence of the query formulation of a topic on its h‐index. In order to generate pure random sets of documents, we used N‐grams (N variable) to measure this influence: strings of zeros, truncated at the end. The used databases are WoS and Scopus. The formula ${\rm{h = T}}^{{\textstyle{1 \over \alpha }}} $, proved in Egghe and Rousseau (2006) where T is the number of retrieved documents and α is Lotka's exponent, is confirmed being a concavely increasing function of T. We also give a formula for the relation between h and N the length of the N‐gram: ${\rm{h = D10}}^{ - {\textstyle{{\rm{N}} \over \alpha }}} $ where D is a constant, a convexly decreasing function, which is found in our experiments. Nonlinear regression on ${\rm{h = T}}^{{\textstyle{1 \over \alpha }}} $ gives an estimation of α, which can then be used to estimate the h‐index of the entire database (Web of Science [WoS] and Scopus): ${\rm{h = S}}^{{\textstyle{1 \over \alpha }}} $, where S is the total number of documents in the database.
Self‐citation as an impact‐reinforcing mechanism in the science system
Authors: van Raan Anthony F.J. 
Published: May 2008

AbstractPrevious research has demonstrated that lower performance groups have a larger size‐dependent cumulative advantage for receiving citations than do top‐performance groups. Furthermore, regardless of performance, larger groups have less not‐cited publications. Particularly for the lower performance groups, the fraction of not‐cited publications decreases considerably with size. These phenomena can be explained with a model in which self‐citation acts as a promotion mechanism for external citations. In this article, we show that for self‐citations, similar size‐dependent scaling rules apply as for citations, but generally the power law exponents are higher for self‐citations as compared to citations. We also find that the fraction of self‐citations is smaller for the higher performance groups, and this fraction decreases more rapidly with increasing journal impact than that for lower performance groups. An interesting novel finding is that the variance in the correlation of the number of self‐citations with size is considerably less than the variance for external citations. This is a clear indication that size is a stronger determinant for self‐citations than it is for external citations. Both higher and particularly lower performance groups have a size‐dependent cumulative advantage for self‐citations, but for the higher performance groups only in the lower impact journals and in fields with low citation density.
Pancreatic aplasia in a fetus with asplenia‐cardiovascular defect‐heterotaxy (Ivemark syndrome)
Authors: Konstantinidou Anastasia , Sifakis Stavros , Koukoura Ourania , Mantas Nikitas , Agrogiannis George , Patsouris Efstratios 
Published: May 2008

AbstractBACKGROUND: Asplenia or polysplenia and complex cardiovascular defects, in association with disturbed body symmetry and malposition of internal organs, constitute the main corpus of malformations in the heterogeneous group of heterotaxy disorders. In affected pregnancies, prenatal diagnosis is possible by ultrasonography, while prognosis and counseling largely depend upon the severity of the cardiac defect. CASE: We present a 25 week gestation fetus with typical findings of asplenia–cardiovascular defect–heterotaxy (Ivemark syndrome) and aplasia of the pancreas. CONCLUSIONS: Pancreatic aplasia emerges as an additional phenotypic feature in Ivemark syndrome and raises the possibility of total pancreatic insufficiency of the affected neonate as an additional, although rare, clinical consideration. Birth Defects Research (Part A) 2008. © 2008 Wiley‐Liss, Inc.
Computer‐Based De Novo Design, Synthesis, and Evaluation of Boronic Acid‐Based Artificial Receptors for Selective Recognition of Dopamine
Authors: Jin Shan , Li Minyong , Zhu Chunyuan , Tran ViLinh , Wang Binghe 
Published: May 2008

AbstractDopamine is an important neurotransmitter that plays important roles in various physiological and pathological processes, such as Parkinson's disease. Chemosensors for dopamine have a number of potential applications. On the basis both of the strong and reversible complexation between the boronic acid moiety and a diol functional group and computational chemistry studies, we have designed a series of four compounds for selective three‐point recognition of dopamine, which include boronic acid–diol complexation, aromatic–hydrophobic interactions, and ionic interactions between a carboxylate and a protonated amino group. These compounds were synthesized in seven or eight linear steps and showed dopamine selectivity of up to tenfold over epinephrine. NMR spectroscopy experiments were conducted to probe the structures of the receptor–dopamine complexes. These receptors are the first to show such significant selectivity for dopamine over epinephrine in aqueous solution under near physiological conditions.