bluuebunny/crossref_metadata_2025_split huggingface dataset:
Normal reference values of ratios of blood flow velocities in internal carotid artery to those in common carotid artery using Doppler sonography
Authors: Kochanowicz Jan , Turek Grzegorz , Rutkowski Robert , Mariak Zenon , Szydlik Piotr , Lyson Tomasz , Krejza Jaroslaw 
Published: June 2008

AbstractPurpose.The ratios of of blood flow velocities in the internal carotid artery (ICA) to those in the common carotid artery (CCA) (VICA/VCCA) are used to identify patients with critical ICA narrowing, but their normal reference values have not been established. We provide reference data for the VICA/VCCA ratios for the peak systolic velocity (PSV), mean velocity (MV), and end‐diastolic velocity (EDV) measured in a large group of healthy subjects.Methods.We examined 343 healthy subjects with color duplex sonography. They were divided into 3 age groups: group I, <40 years; group II, 40–60 years; group III, >60 years.Results.The values of VICA/VCCA ratio for the PSV were as follows [mean (upper and lower reference values)]. In women, group I: 0.81 (0.48–1.14), group II: 0.88 (0.36–1.40), group III: 0.9 (0.36–1.40). In men, group I: 0.65 (0.32–0.98), group II: 0.72 (0.39–1.05), group III: 0.91 (0.27–1.56). The VICA/VCCA ratio for PSV increased with age only in men and its values were significantly higher in women than in men in the group I and group II age groups.Conclusion.This study provides normal reference values for the VICA/VCCA ratios for PSV and shows that the ratio varies with age and sex. The upper reference limit for the ratio can serve as an aid in the more specific identification of patients with minor or mild ICA narrowing. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2009
Pulsatile tinnitus in a case of traumatic temporal extradural arteriovenous fistula: Carotid duplex sonography findings before and after embolization
Authors: Tan Teng‐Yeow , Lin Yun‐Yu , Schminke Ulf , Chen Ting‐Yao 
Published: June 2008

AbstractCarotid duplex sonography (CDS) is regarded as a screening tool for lateral dural arteriovenous fistulae (AVF). However, data on evaluating long‐term effects of endovascular treatment are limited. We report the CDS findings in the feeding arteries of a traumatic temporal extradural AVF before and after transarterial embolization. Volume flow of the left common carotid artery was greater than the right (433 ml/minute versus 294 ml/minute right) and the resistance index of the left external carotid artery was lower than the right (0.69 left versus 0.84 right). Both parameters returned to normal 4 months after embolization, thus confirming successful endovascular treatment. © 2008 Wiley Periodicals, Inc. J Clin Ultrasound, 2008
Hadwiger's conjecture for quasi‐line graphs
Authors: Chudnovsky Maria , Fradkin Alexandra Ovetsky 
Published: June 2008

AbstractA graph G is a quasi‐line graph if for every vertex v ∈ V(G), the set of neighbors of v in G can be expressed as the union of two cliques. The class of quasi‐line graphs is a proper superset of the class of line graphs. Hadwiger's conjecture states that if a graph G is not t‐colorable then it contains Kt + 1 as a minor. This conjecture has been proved for line graphs by Reed and Seymour. We extend their result to all quasi‐line graphs. © 2008 Wiley Periodicals, Inc. J Graph Theory 59: 17–33, 2008
Finite homomorphism‐homogeneous tournaments with loops
Authors: Ilić Andreja , Mašulović Dragan , Rajković Uroš 
Published: June 2008

AbstractA structure is called homogeneous if every isomorphism between finite substructures of the structure extends to an automorphism of the structure. Recently, Cameron and Nešetřil introduced a relaxed version of homogeneity: we say that a structure is homomorphism‐homogeneous if every homomorphism between finite substructures of the structure extends to an endomorphism of the structure. In this article we characterize homomorphism‐homogeneous finite tournaments where vertices are allowed to have loops. © 2008 Wiley Periodicals, Inc. J Graph Theory 59: 45–58, 2008
Generation of dopamine neurons from embryonic stem cells in the presence of the neuralizing activity of bone marrow stromal cells derived from adult mice
Authors: Shintani Aki , Nakao Naoyuki , Kakishita Koji , Itakura Toru 
Published: June 2008

AbstractStromal cell lines such as PA6 and MS5 have been employed for generating dopamine (DA) neurons from embryonic stem (ES) cells. The present study was designed to test whether bone marrow stromal cells (BMSC) derived from adult mice might be available as a feeder layer to produce DA cells efficiently from ES cells. When ES cells were grown on BMSC in the presence of fibroblast growth factor 8 (FGF8) and sonic hedgehog (SHH), about 40% of TuJ1‐positive neurons expressed tyrosine hydroxylase (TH). Because these cells labeled with TH were negative for dopamine‐β‐hydroxylasae (DBH), the marker for noradrenergic and adrenergic neurons, the TH‐positive cells were most likely DA neurons. They indeed expressed midbrain DA neuron markers such as Nurr 1, Ptx‐3, and c‐ret and were capable of synthesizing and releasing DA in vitro. Furthermore, DA neurons differentiated from ES cells in this differentiation protocol survived transplantation in rats with 6‐hydroxydopamine lesions and reversed the lesion‐induced circling behavior. The data indicate that BMSC can facilitate an efficient induction of DA neurons from ES cells and that the generated DA neurons are biologically functional both in vitro and in vivo. Insofar as BMSC have recently been employed in autologous cell therapy for ischemic heart and arteriosclerotic limb diseases, the present study raises the possibility that autologous BMSC can be applied in future cell transplantation therapy in Parkinson's disease. © 2008 Wiley‐Liss, Inc.
Expression of Foxp4 in the developing and adult rat forebrain
Authors: Takahashi Kaoru , Liu Fu‐Chin , Hirokawa Katsuiku , Takahashi Hiroshi 
Published: June 2008

AbstractMany members of the Fox family are transcription factors that regulate the morphogenesis of various organs. In the present study, we examined the expression pattern of Foxp4, a member of the Foxp subfamily, and compared its pattern with the patterns of Foxp2 and Foxp1 in the developing rat brain. In general, these three Foxp genes shared partially overlapping and yet differentially regulated expression patterns in the striatum, the cerebral cortex, and the thalamus during development. In the developing dorsal telencephalon, a mediolateral gradient of Foxp4 was present in the cortical primordium, with high levels in the ventricular zone of the medial cortex. By contrast, no gradient of Foxp2 and Foxp1 was detected in the dorsal telencephalon. At later stages, Foxp4 was expressed throughout all cortical layers as opposed to the layer‐specific expression of Foxp2 and Foxp1. In the developing striatum, the pattern of Foxp4 expression was distinct from the patterns of Foxp2 and Foxp1. The spatial expression pattern of Foxp4 was similar to that of Foxp2 during the early embryonic stage. However, from the late embryonic stage to postnatal day 4, Foxp4 was expressed in a mediolateral gradient and decreased in the striosomal compartment, in contrast to the striosomal expression of Foxp2 and homogeneous expression of Foxp1. Foxp4 was developmentally down‐regulated such that Foxp4 was undetectable in the forebrain after postnatal day 14, whereas Foxp2 and Foxp1 were persistently expressed in adulthood. Given that Foxp4, Foxp2, and Foxp1 are capable of heterodimerization for transcriptional regulation, the partially overlapping expression patterns of Foxp4, Foxp2, and Foxp1 in different domains of the developing forebrain suggest that each member and/or different combinatory actions of the Foxp subfamily may play a pivotal role in regulating forebrain development. © 2008 Wiley‐Liss, Inc.
Pressurized CEC of neutral and charged solutes using silica monolithic stationary phases functionalized with 3‐(2‐aminoethylamino)propyl ligands
Authors: Huang Guihua , Zeng Wencan , Lian Qiuyan , Xie Zenghong 
Published: June 2008

AbstractA novel silica monolithic stationary phase functionalized with 3‐(2‐aminoethylamino)propyl ligands for pressurized CEC has been presented. The monolithic capillary columns were prepared by a sol‐gel process in 75 μm id fused‐silica capillaries and followed by a chemical modification. The diamino groups on the surface of the stationary phase are meant to generate the chromatographic surface and a substantial anodic EOF as well as to provide electrostatic interaction sites for charged solutes. The electrochromatographic characterization and column performance were evaluated by a variety of neutral and charged solutes. It was observed that the anodic EOF for the diamine‐bonded monolith was greatly affected by the reaction time with 3‐(2‐aminoethylamino)propyltrimethoxysilane and the PEG amount in the sol‐gel reaction mixture in addition to the mobile phase conditions. The monolithic stationary phase exhibited hydrophilic interaction chromatographic behavior toward neutral solutes. Good separations of various solutes including phenols, nucleic acid bases, nucleosides and nucleotides were achieved under different experimental conditions. Fast and efficient separations were obtained with high plate counts reaching more than 130 000 plates/m.
Non‐destructive assessment of inhibition of demineralization in dental enamel irradiated by a λ = 9.3‐µm CO2 laser at ablative irradiation intensities with PS‐OCT
Authors: Can Anna M. , Darling Cynthia L. , Ho Chi , Fried Daniel 
Published: June 2008

AbstractBackground and ObjectivePolarization sensitive optical coherence tomography (PS‐OCT) has great promise for the non‐destructive assessment of the efficacy of anti‐caries agents such as fluoride and thermal laser treatments on enamel surfaces. The purpose of this study was to demonstrate that PS‐OCT can be used to measure demineralization in craters/incisions prepared in enamel by a CO2 laser operating at the high irradiation intensities required for cavity preparations.Materials and MethodsIncisions in bovine enamel surfaces were produced by a CO2 laser used with a water spray. The laser was operated at λ = 9.3 µm with a pulse duration of 15 µs and an incident fluence of 20 J/cm2. The laser treatments were also combined with topical fluoride treatments. A PS‐OCT system operating at 1,310 nm was used to acquire polarization resolved images of six areas including sound and laser‐ablated+topical fluoride treated zones on each sample. After imaging the teeth, they were sectioned and the thin sections were examined with polarized light microscopy (PLM) and transverse microradiography (TMR). The integrated reflectivity and lesion depth derived from the PS‐OCT scans, the integrated mineral loss and depth measured using TMR and the lesion depth measured with PLM were acquired for each area on the fifteen samples for comparison.ResultsThe integrated reflectivity and depth in the areas treated by the laser and fluoride were significantly lower (P<0.05) than for the untreated enamel. Similar results were observed for TMR and PLM.ConclusionsThese results suggest that PS‐OCT has great potential for the non‐destructive “in vivo” assessment of the inhibition of demineralization by lasers at ablative irradiation intensities with and without topical fluoride application. Lesers Surg. Med. 40:342–349, 2008. © 2008 Wiley‐Liss, Inc.
Investigation of Nanoparticle Coating by Fluorescence Correlation Spectroscopy
Authors: Jurkiewicz Piotr , Koňák Čestmír , Šubr Vladimír , Hof Martin , Štĕpánek Petr , Ulbrich Karel 
Published: June 2008

AbstractProtecting gene delivery vectors by hydrophilic copolymer coating is a promising approach in targeted gene therapy. Herein we demonstrate the usefulness of FCS in characterizing the coating process of a virus model – latex beads with coumarin‐labeledN‐(2‐hydroxypropyl)methacrylamide copolymer containing thiazolidine‐2‐thione groups. FCS gives an estimation of the average number of polymer chains coating the latex bead, which agrees with light scattering results, giving an evidence of quality of the vector surface modification. FCS is advantageous because it decreases the sample consumption by a factor of 1 000. The coumarin label showed advantages over the previously used fluorescein‐based one.magnified image
The Process of Functional Conjugated Organic Polymers Derived from Triple‐Bond Building Blocks
Authors: Li Cuihong , Li Yuliang 
Published: June 2008

AbstractPolyacetylenes, poly(p‐phenyleneethynylenes), and polydiacetylenes, as conjugated polymers derived from triple‐bond containing building blocks, attain considerable attention because of their electronic and photoconduction properties. In this review, recent studies on the design and synthesis of conjugated polymers derived from triple‐bond building blocks are summarized with an emphasis on the developments in our group in recent years. Our intense attention is focused on constructing different molecular systems with enhanced light‐harvesting efficiency, and determining the functional properties of conjugated organic polymers. The conjugated organic polymers that appear in this review are useful candidates for various potential applications because of their extraordinary optical and electronic properties. The potential applications of the conjugated polymer‐containing systems are explored.magnified image
Morphological Behavior of Polystyrene‐block‐Polylactide/Polystyrene‐block‐Poly(ethylene oxide) Blends
Authors: Mao Huiming , Hillmyer Marc A. 
Published: June 2008

AbstractThe morphological behavior of PS‐containing diblock copolymer blends is reported. Three sets of PS/PLA and PS/PEO blends are prepared and evaluated by SAXS, WAXS, DSC, and DMA. No macrophase separation is observed, and the formation of PLA/PEO composite cylinders is identified by SAXS for all compositions. The PLA and PEO segments in these blends have been found to be miscible and the crystallization of the confined PEO is suppressed in the ordered nanostructures. The domain spacing, diameter of composite cylinders, and order/disorder transition temperature could be tuned by varying the blend composition in the binary blends.magnified image
A Comparative Study of Nanosilica/Poly(propylene) Composites Prepared by Reactive Compatibilization
Authors: Chen Jing Hua , Rong Min Zhi , Ruan Wen Hong , Mai Yu Liang , Zhang Ming Qiu 
Published: June 2008

AbstractA comparative study of nano‐SiO2/PP composites prepared by reactive compatibilization was conducted. Nano‐SiO2 was first grafted with three polymers bearing specific reactive groups. The grafted particles were then melt‐compounded with functionalized and matrix PP. Due to the reaction between the grafted polymers and functionalized PP, nano‐SiO2 was covalently connected to the matrix and the mechanical properties of the nanocomposites were significantly improved. It was found that chain flexibility of the graft polymers is critical for inducing plastic deformation of the matrix, provided that interfacial chemical bonding has been built up.magnified image
Temperature‐ and pH‐Sensitive Nanocomposite Gels with Semi‐Interpenetrating Organic/Inorganic Networks
Authors: Song Liyuan , Zhu Meifang , Chen Yanmo , Haraguchi Kazutoshi 
Published: June 2008

AbstractAn intelligent nanocomposite hydrogel with a semi‐interpenetrating organic/inorganic network was synthesized through in situ free‐radical polymerization of NIPA in the presence of an inorganic clay and linear PAA. The resulting semi‐interpenetrating nanocomposite gels (sI‐NC gels) showed mechanical and swelling/deswelling properties greatly superior to those of other PNIPA/PAA hydrogels. The sI‐NC gels repeatedly changed their swelling behavior in response to both temperature and pH while retaining their remarkable mechanical properties. The structure and homogeneity of these networks were studied and related to the properties of sI‐NC gels and the hydrogen bonding interactions among the constituents.magnified image
Flow‐Induced Orientation in Miscible Crystalline Polymer Blends of Poly(vinylidene fluoride) and Poly[(3‐hydroxybutyrate)‐co‐(3‐hydroxyvalerate)]
Authors: Kaito Akira , Nakayama Kazuo , Shimizu Hiroshi 
Published: June 2008

AbstractOriented films of miscible polymer blends of poly(vinylidene fluoride) and poly[(3‐hydroxybutyrate)‐co‐(3‐hydroxyvalerate)] were prepared using a flow‐orientation technique. The lamellar structure and crystal orientation depended upon composition and flow temperature (Tflow). An interlamellar exclusion structure was induced in the blend flow‐oriented below 150 °C, whereas an interlamellar inclusion structure was developed above 150 °C. The crystal orientation of PHBHV was affected by the lamellar structures because the PHBHV chains crystallized in the pre‐existing crystalline morphology of PVDF. Crystallization of PHBHV was markedly restricted at lower PHBHV contents.magnified image
Alkyl Zinc Chlorides as New Initiators for the Polymerization and Copolymerization of Isobutene
Authors: Guerrero Antonio , Kulbaba Kevin , Bochmann Manfred 
Published: June 2008

AbstractMixtures of RZnCl and tBuCl (R = Et) initiate the polymerization of isobutene in the temperature range of (−35)—(+35) °C. The order of addition of the reagents is important for effective polymerization. Increasing the solubility of the zinc reagent (R = n‐octyl) and use of cumyl chloride as co‐initiator provides a system that is active from (−90)—(+35) °C. The molecular weights show a remarkably small temperature dependence, EDP = −3.3 kJ · mol−1, compared to EDP = −23 kJ · mol−1 in classical systems (AlCl3, EtAlCl2). The molecular weights increase with decrease in zinc concentration and are consistently higher for n‐octyl zinc chloride, as expected for a bulkier, less coordinating counteranion. The polymerizations are not retarded by isoprene addition; homopolymers and copolymers show essentially identical conversions and molecular weights.magnified image
Organometallic Polymer Light‐Emitting Diodes Derived from a Platinum(II) Polyyne Containing the Bithiazole Ring
Authors: Wong Wai‐Yeung , Zhou Gui‐Jiang , He Ze , Cheung Kai‐Yin , Ng Alan Man‐Ching , Djurišić Aleksandra B. , Chan Wai‐Kin 
Published: June 2008

AbstractThe synthesis, thermal, and photoluminescence properties of novel platinum metallopolyynes of bithiazole derivatives trans‐[Pt(PR3)2‐C≡C‐Ar‐C≡C]n (Ar = 4,4′‐dibutyl‐2,2′‐bithiazole‐5,5′‐diyl P1; 4,4′‐dinonyl‐2,2′‐bithiazole‐5,5′‐diyl P2) and their molecular model complexes are described. The structural properties of the dinuclear model compound for P1 have been examined by X‐ray crystallography. In view of the electron‐donating and electron‐withdrawing nature of the thiazole rings in the main chain, a strong π‐conjugated system that features unique donor–acceptor interactions is created, which results in optical bandgaps of 2.40 eV. The optical gap of the polymer is notably reduced as compared to that for the more electron‐rich bithienyl analogue. Multi‐layer polymer light‐emitting diodes have been fabricated with the metallopolymer as the emitting layer, which give a green light color with the Commission Internationale de L'Eclairage (CIE) chromaticity coordinates of (0.26, 0.58) at 8 V.magnified image
Atomic Force Microscopy Characterization and Interpretation of Thin‐Film Poly(butylene adipate) Spherulites with Ring Bands
Authors: Frömsdorf Andreas , Woo Eamor M. , Lee Li‐Ting , Chen Yu‐Fan , Förster Stephan 
Published: June 2008

AbstractAtomic force microscopy characterization has been conducted to reveal the morphological difference between single‐ring bands in poly(butylene adipate) (PBA). Furthermore, morphological features of the ring‐less Maltese‐cross spherulites are compared to the ring‐band spherulites. Periodic changes in height seem to be common for either the ring‐band or ring‐less (Maltese‐cross) crystal domains; however, the steepness in height change is greater for the ring‐band crystal, while height change in the ring‐less crystal exhibits a terrace‐like layer pattern. In the ring‐band crystal region, the lamellar stalks, which taper off to pointed needle‐like stalks, monotonously protrude out of the layers of softer materials, with no signs of twisting, bending, or turning. In contrast, all lamellae in the ring‐less (Maltese‐cross) crystal region are uniform platelets arranged like flower petals in a layered pattern.magnified image
G protein‐coupled receptors of the hypothalamic–pituitary–gonadal axis: A case for gnrh, LH, FSH, and GPR54 receptor ligands
Authors: Heitman Laura H. , IJzerman Adriaan P. 
Published: June 2008

AbstractThe hypothalamic–pituitary–gonadal (HPG) axis, important in reproduction and sex hormone‐dependent diseases, is regulated by a number of G protein‐coupled receptors. The recently “deorphanized” GPR54 receptor activated by the peptide metastin is thought to be the key regulator of the axis, mainly by releasing gonadotropin‐releasing hormone (GnRH) from the hypothalamus. The latter decapeptide, through the activation of the GnRH receptor in the anterior pituitary, causes the secretion of luteinizing hormone (LH) and follicle‐stimulating hormone (FSH), which subsequently activate their respective receptors on the gonadotrope cells. In this review we will discuss the small molecule agonists and antagonists that are currently being developed to intervene with the action of these four receptors. For GnRH receptors, 14 different chemical classes of non‐peptidic antagonists have been reported, while for the LH receptor three classes of agonists have been described. Both agonists and antagonists have been introduced for the FSH receptor. Recently, the first non‐peptidic agonist for GPR54 was reported. © 2008 Wiley Periodicals, Inc. Med Res Rev, 28, No. 6, 975–1011, 2008
Novel shaped‐beam microstrip slot array series FED by stepped‐impedance line
Authors: Hanqing M. A. , Chu Qing‐Xin , Qiuyi Zhang 
Published: June 2008

AbstractA series‐fed eight‐slot microstrip array antenna operating at 3.5 GHz with a cosecant‐squared shape beam is presented. The shaped radiation pattern is achieved by changing only the characteristic impedance of the series fed line between slots. The proposed antenna has a shaped‐beam with elevation coverage of 35°, a gain of 10.86 dBi, and side lobe levels less than −19 dB. Since the slots and fed strip are fabricated on a single substrate, the antenna is easy to manufacture and low cost. Experimental results demonstrate the validity of this design. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 50: 2434–2437, 2008; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23662