bluuebunny/crossref_metadata_2025_split huggingface dataset:
Structure‐Dependent Photophysics Studied in Single Molecules of Polythiophene Derivatives
Authors: Sugimoto Toshikazu , Ebihara Yohei , Ogino Kenji , Vacha Martin 
Published: June 2007

AbstractWe report on the photophysical characterization at the single‐molecule level of a graft copolymer consisting of a polythiophene backbone and long polystyrene branches. The presence of the branches prevents the polymer chain from forming a collapsed conformational state. The photophysical properties of the resulting solution‐like conformation are studied by measuring single‐molecule photobleaching dynamics, emission polarization anisotropy and emission spectra. The results are compared with those obtained on the same polythiophene derivative without the branches. It is found that the presence of the branches is a decisive factor in determining the photophysical properties of the polymers on the single‐molecule level.
Energy‐efficient target detection in sensor networks using line proxies
Authors: Lee Jangwon , Yu Wei , Fu Xinwen 
Published: June 2007

AbstractOne of the fundamental and important operations in sensor networks is sink–source matching, i.e. target detection. Target detection is about how a sink finds the location of source nodes observing the event of interest (i.e. target activity). This operation is very important in many sensor network applications such as military battlefield and environment habitats. The mobility of both targets and sinks brings significant challenge to target detection in sensor networks. Most existing approaches are either energy inefficient or lack of fault tolerance in the environment of mobile targets and mobile sinks. Motivated by these, we propose an energy‐efficient line proxy target detection (LPTD) approach in this paper.
The basic idea of LPTD is to use designated line proxies as rendezvous points (or agents) to coordinate mobile sinks and mobile targets. Instead of having rendezvous nodes for each target type as used by most existing approaches, we adopt the temporal‐based hash function to determine the line in the given time. Then the lines are alternated over time in the entire sensor network. This simple temporal‐based line rotation idea allows all sensor nodes in the network to serve as rendezvous points and achieves overall load balancing. Furthermore, instead of network‐wide flooding, interests from sinks will be flooded only to designated line proxies within limited area. The interest flooding can further decrease if the interest has geographical constraints. We have conducted extensive analysis and simulations to evaluate the performance of our proposed approach. Our results show that the proposed approach can significantly reduce overall energy consumption and target detection delay. Copyright © 2007 John Wiley & Sons, Ltd.
Crystalline bodies in Pap smear—A forgotten entity
Authors: Kapila Kusum , Al‐Juwaiser Ahlam , Haji Bahiyah E. 
Published: June 2007

AbstractCrystalline bodies were detected in the Pap smear of a 34‐wk pregnant woman who presented with postcoital bleeding. Diagn. Cytopathol. 2007;35:423. © 2007 Wiley‐Liss, Inc.
The fine needle aspiration biopsy diagnostic criteria of proliferative breast lesions: A retrospective statistical analysis of criteria for papillomas and radial scar lesions
Authors: Field Andrew , Mak Alison 
Published: June 2007

AbstractThis study aimed to analyze statistically the accuracy of fine needle aspiration biopsy cytological criteria in diagnosing epithelial hyperplasia with atypia (EHA), papillary lesions (PAP), and radial scar/complex sclerosing lesions (RS/CSL). The 42 criteria studied were extracted from a literature review and those developed and used in our department.Cytological cases with diagnoses of EHA, PAP, and RS/CSL for the period of 1997–2001 were correlated with relevant histological follow‐up and the positive predictive power of these diagnoses have been presented in an earlier publication. Some 77 cases with definite, specific histological diagnoses of atypia or a more severe lesion, PAP and RS/CSL, were reviewed and scored using 55 cytological criteria.As the group of EHA and RS/CSL yielded a smaller number of cases, these were grouped together in the statistical analysis and compared to PAP. The cytological features, which were most diagnostic for PAP, were stellate (Odds ratio 1.75) and meshwork (Odds ratio 3.29) tissue fragments, while the presence of tubular structures was inversely proportional to the histological outcome of PAP. True papillary fragments were uncommon and not statistically significant in diagnosing PAP of the breast. Diagn. Cytopathol. 2007;35:386–397. © 2007 Wiley‐Liss, Inc.
Ciliated foregut cyst of pancreas: Cytologic findings on endoscopic ultrasound‐guided fine‐needle aspiration
Authors: Woon Carolyn S. , Pambuccian Stefan E. , Lai Rebecca , Jessurun Jose , Gulbahce H. Evin 
Published: June 2007

AbstractThe cytologic findings of a ciliated foregut cyst of the pancreas diagnosed by endoscopic ultrasound‐guided fine‐needle aspiration (FNA) are described. Cytologic features of ciliated foregut cysts include the presence of ciliated columnar cells and detached ciliary tufts in a cystic fluid background with amorphous debris and rare macrophages. These cytologic findings are clearly distinct from those of cystic mucinous neoplasms and other pancreatic cysts with which the ciliated foregut cyst may be confused. To the best of our knowledge, this is the first case reporting the cytologic findings of a pancreatic ciliated foregut cyst sampled by endoscopic ultrasound‐guided FNA. We believe that the distinctive and characteristic cytologic features can allow a preoperative cytologic diagnosis of this highly unusual pancreatic cystic lesion. Diagn. Cytopathol. 2007;35:433–438. © 2007 Wiley‐Liss, Inc.
Cytological study of 20 cases of solid‐papillary carcinoma of the breast
Authors: Yamada Makoto , Otsuki Yoshiro , Shimizu Shin‐ichi , Tanioka Fumihiko , Ogawa Hiroshi , Kobayashi Hiroshi 
Published: June 2007

AbstractSolid‐papillary carcinoma (SPC) of the breast is a rare variant of low‐grade intraductal carcinoma but there are few cytological studies. We examined 20 cases of SPC of the breast, aged 31–80 (mean age 66.0 yr), to define the cytological features. In each of the cytological specimens, we could find both malignant and benign cytological features; the former were characterized by hypercellularity, highly discohesive clusters, numerous isolated cells, and severe overcrowding cells, while the latter were marked by small and bland nuclei, a low nuclear‐cytoplasmic ratio, and inconspicuous nucleoli. Neither abnormal naked nuclei of tumor cell origin nor oval naked nuclei of myoepithelial cell origin were seen.We also reviewed the cytological findings of SPC as well as neuroendocrine carcinomas with intraductal components that had been reported and we concluded that the coexistence of malignant and benign features was the most characteristic cytological feature of SPC. Diagn. Cytopathol. 2007;35:417–422. © 2007 Wiley‐Liss, Inc.
Anomeric Interactions in Pentafluoroethylimidosulfurous Dichloride, CF3CF2N=SCl2: Structural, Conformational and Configurational Properties in the Gaseous and Condensed Phases
Authors: Robles Norma L. , Álvarez Rosa M. S. , Cutin Edgardo H. , Della Védova Carlos O. , Erben Mauricio F. , Boese Roland , Willner Helge , Mews Rüdiger 
Published: June 2007

AbstractThe structural, conformational, and configurational properties of pentafluoroethylimidosulfurous dichloride (CF3CF2N=SCl2) have been studied by vibrational spectroscopy [IR (vapor) and Raman (liquid)] and quantum chemical calculations [HF, B3LYP and MP2 approximations using the 6‐311+G(d) and 6‐311+G(2df) basis sets]. CF3CF2N=SCl2 exists in the liquid phase as a single (Z) form (C–N bond synperiplanar with respect to the Cl–S–Cl plane; C1 symmetry). The structure was also determined by X‐ray diffraction analysis of a single crystal grown in situ at low temperature. The crystalline solid at 159 K (monoclinic, P21/c, a = 5.2466(10), b = 15.376(3), c = 18.730(3) Å, β = 96.391(3)°, Z = 8) consists of two crystallographically inequivalent (Z) forms. The results are discussed in terms of both hyperconjugative electronic effects and of natural bond orbital (NBO) calculations. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Chlorido‐Bridged MnII Schiff‐Base Complex with Ferromagnetic Exchange Interactions
Authors: Qi Chuan‐Min , Sun Xu‐Xia , Gao Song , Ma Shu‐Lan , Yuan Da‐Qiang , Fan Cui‐Hong , Huang Hai‐Bo , Zhu Wen‐Xiang 
Published: June 2007

AbstractThe preparation, crystal structure, and magnetic properties of the μ‐Cl‐bridged dinuclear complex [Mn(HL)(μ‐Cl)Cl]2 (1) with the Schiff‐base ligand HL, 2‐methyl‐6‐[(pyridine‐2‐ylmethylene)amino]phenol, is reported. Structural studies show that 1 is binuclear with a pair of chlorine atoms bridging the manganese atoms in a central Mn2Cl2 plane, the intramolecular Mn···Mn separation being 3.694 Å. Each manganese atom in 1 is six‐coordinate with two nitrogen atoms (one imine nitrogen and one pyridine nitrogen) and one phenolic oxygen from the neutral tridentate ligand, and three chlorine atoms (one terminal and two bridging) building an elongated octahedral environment. The two octahedra adopt the unique geometry sharing an equatorial‐to‐axial edge with parallel equatorial planes. The hydrogen bonds between the coordinated Cl– anions and hydroxy groups connect the dimeric coordinated units together forming a one‐dimensional chain. Variable temperature susceptibility measurements in the temperature range of 2.0–300 K reveal a ferromagnetic coupling (J = +0.94 cm–1) in the dimer via the double chlorido bridge, and a weak antiferromagnetic coupling (zJ′ = –0.036 cm–1) between the dimers through the intermolecular hydrogen bonding. A comparison of the magnetic coupling of 1 with other structurally similar Mn(μ‐Cl)2Mn compounds is discussed in detail. Complex 1 may provide useful information for the magneto‐structural correlations of this kind of compounds. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Advances in the Synthesis of Aryltetralin Lignan Lactones
Authors: Sellars Jonathan D. , Steel Patrick G. 
Published: June 2007

AbstractEtoposide and tenoposide, derivatives of the aryltetralin lignan lactone podophyllotoxin (5), are clinically important anticancer agents. The structure of podophyllotoxin includes four contiguous chiral centres contained within a stereochemically unstable trans‐fused tetrahydronaphthalene lactone skeleton. Reflecting this challenging structure and important biological role there has been long‐standing interest in developing efficient stereocontrolled syntheses of this class of natural product. This microreview summarises the key developments towards this end focussing on more recent developments both from within the authors group and elsewhere.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Novel Cyclic Phosphate‐Linked Oligosaccharides (CyPLOSs) Covalently Immobilized on Solid Supports for Potential Cation Scavenging
Authors: D'Onofrio Jennifer , Coppola Cinzia , Di Fabio Giovanni , De Napoli Lorenzo , Montesarchio Daniela 
Published: June 2007

AbstractFor potential cation scavenging both from water and from organic solvents, here we propose a synthetic procedure for functionalization of a Tentagel solid support with novel cyclic phosphate‐linked oligosaccharide (CyPLOS) analogues. To establish the feasibility of the synthetic strategy, the cyclic dimer was the model compound selected to be incorporated onto the solid support. This functionalization was achieved through a stepwise solid‐phase synthesis of the linear dimer, obtained by standard phosphoramidite protocols, followed by a synthesis of the cyclic molecule on the resin. The key intermediate in our synthetic strategy was a suitably derivatized sugar phosphoramidite building block, with the secondary hydroxy functions masked as TBDMS ethers. This proved to be an orthogonal protection with respect to the DMT ether, fully compatible with the phosphoramidite and the phosphotriester chemistry used for the oligomerization and the cyclization process onto the solid support, respectively. Conditions for the total unmasking of the hydroxy groups of the cyclic dimer, not affecting the integrity of the cyclic structure nor its linkage with the solid matrix, have been optimized. Gel‐phase31P NMR spectroscopy has been used extensively here to monitor the efficiency of the reactions carried out on the solid support.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Synthesis and Structure of an α,β‐D‐CNA Featuring a Noncanonical α/β Torsion Angle Combination within a Tetranucleotide
Authors: Le Clézio Ingrid , Dupouy Christelle , Lavedan Pierre , Escudier Jean‐Marc 
Published: June 2007

AbstractSynthesis and structural analysis of a (SC5′,RP)‐configured α,β‐D‐CNA TT within a tetranucleotide composed of four thymidine units showed that the solution structure determined at the dinucleotide level for the α,β‐D‐CNA with α and β torsional angles constrained to noncanonical values [gauche(+), trans] was unchanged and imposed a sharp turn in the single‐stranded tetranucleotide. The overall structure of the tetranucleotide T4 has a hairpin loop shape. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Multiplex PCR with minisequencing as an effective high‐throughput SNP typing method for formalin‐fixed tissue
Authors: Gilbert Marcus T. P. , Sanchez Juan J. , Haselkorn Tamara , Jewell Laurence D. , Lucas Sebastian B. , Van Marck Eric , Børsting Claus , Morling Niels , Worobey Michael 
Published: June 2007

AbstractExtensive collections of formalin‐fixed paraffin‐embedded (FFPE) tissues exist that could be exploited for genetic analyses in order to provide important insights into the genetic basis of disease or host/pathogen cointeractions. We report here an evaluation of a 44 SNP multiplex genotyping method, multiplex PCR with minisequencing (MPMS), on 92 DNA extractions performed on six archival FFPE samples of variable DNA quality, which date between 9 and 25 years old. On the three extracts with highest quality, we found the assay efficiency to be near 100%. However, the efficiency of the lowest quality extracts varied significantly. In this study, we demonstrate that although direct measures of DNA concentration in the extracts provide no useful information with regard to subsequent MPMS success, the success of the assay can be determined to some degree a priori, through initial screening of the DNA quality using a simple quantitative real‐time PCR (qPCR) assay for nuclear DNA, and/or an assay of the maximum PCR amplifiable size of nuclear DNA. MPMS promises to be of significant use in future genetic studies on FFPE material. It provides a streamlined approach for retrieving a large amount of genetic information using simple, single reactions and minute amounts of archival tissue/DNA. In the light of this evidence, we suggest that the systematic screening of FFPE collections may in the future provide valuable insights into the past.
A hybrid microdevice with a thin PDMS membrane on the detection window for UV absorbance detection
Authors: Ma Bo , Zhou Xiaomian , Wang Gang , Dai Zhongpeng , Qin Jianhua , Lin Bingcheng 
Published: June 2007

AbstractWe exploited a PDMS‐quartz hybrid microchip with a thin PDMS membrane on the concave detection window for UV absorbance detection. The thickness of the PDMS membrane is about 100 μm, with high UV transmittance. As compared to a PDMS‐quartz hybrid chip with a common detection window, the proposed one exhibited over an one order of magnitude sensitivity enhancement, and an about two orders of magnitude S/N increase for gastrodin (p‐hydroxymethylphenyl‐β‐D‐glucopyranoside). In addition, the limit of the detection wavelength has been extended from 240 to 210 nm, which is otherwise impossible for a traditional PDMS‐quartz hybrid microchip. This kind of microchip has the potential for a large range of applications in an integrated microfluidic system with UV detection.
Rapidly profiling blood–brain barrier penetration with liposome EKC
Authors: Wang Yongjun , Sun Jin , Liu Hongzhuo , He Zhonggui 
Published: June 2007

AbstractThis report intended to study the potential of liposome EKC (LEKC) as a convenient and high‐throughput screening tool to assess drug penetration across the blood–brain barrier (BBB). The retention factors (k) of 24 structurally diverse compounds were determined with LEKC and vesicle EKC (VEKC), respectively. Principal component analysis of the steady‐state concentrations ratio of compounds in the brain and in the blood expressed as log BB, log kLEKC, log kVEKC, and other lipophilic descriptors including octanol/water partition coefficient (Clog P), octanol/water distribution coefficients (log D7.4), and polar surface area (PSA), showed the maximum similarity of partitioning processes in LEKC to drug penetration across the BBB. Furthermore, the log BB were correlated with the above five lipophilic descriptors, and the results showed that log kLEKC gave the better correlation coefficient (r2 = 0.811, p <0.0001) than those of log D7.4, Clog P, PSA, and log kVEKC (r2 = 0.730, 0.672, 0.627, and 0.620, p <0.0001). This is the first report of the use of LEKC as a promising rapid tool to profile drug penetration across the BBB.
Isolation of smooth‐type lipopolysaccharides to electrophoretic homogeneity
Authors: Pupo Elder , Hardy Eugenio 
Published: June 2007

AbstractThe high structural heterogeneity of smooth‐type lipopolysaccharides (LPS) enormously complicates the isolation of their constituent molecular species. Proof of concept is given here on the feasibility of using preparative slab‐PAGE to isolate highly homogeneous smooth‐type LPS glycoforms. LPS species (from 3.6 to 14.2 kDa) from Escherichia coli K‐235 were separated by preparative slab‐PAGE and recovered by utilizing the combined on‐gel LPS reverse staining, extrusion, and passive elution techniques. As a result, 15 electrophoretically pure LPS fractions were obtained. The LPS content in the recovered fractions ranged from 280 ng (intermediate mobility glycoforms) to 411 μg (highest mobility glycoforms). The quantities of LPS fractions were sufficient to allow quantitation of the Limulus amebocyte lysate (LAL) activities of these distinct‐molecular‐mass LPS species, in the range from (1.1 ± 0.1)×103 to (8.7 ± 0.3)×105 endotoxin units (EU)/mL, by standard LAL assay. We have thus definitively demonstrated that slab‐PAGE may be a suitable platform to more selectively purify individual glycoform fractions from smooth‐type LPS.
Investigating nonlinear speculation in cattle, corn, and hog futures markets using logistic smooth transition regression models
Authors: Röthig Andreas , Chiarella Carl 
Published: June 2007

AbstractThis study explores nonlinearities in the response of speculators' trading activity to price changes in live cattle, corn, and lean hog futures markets. Analyzing weekly data from March 4, 1997 through December 27, 2005, the authors reject linearity in all of these markets. Using smooth transition regression models, the authors found a similar structure of nonlinearities with regard to the number of different regimes, the choice of the transition variable, and the value at which the transition occurs. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 28:719–737, 2007
Canonical valuation and hedging of index options
Authors: Gray Philip , Edwards Shane , Kalotay Egon 
Published: June 2007

AbstractCanonical valuation is a nonparametric method for valuing derivatives proposed by M. Stutzer (1996). Although the properties of canonical estimates of option price and hedge ratio have been studied in simulation settings, applications of the methodology to traded derivative data are rare. This study explores the practical usefulness of canonical valuation using a large sample of index options. The basic unconstrained canonical estimator fails to outperform the traditional Black–Scholes model; however, a constrained canonical estimator that incorporates a small amount of conditioning information produces dramatic reductions in mean pricing errors. Similarly, the canonical approach generates hedge ratios that result in superior hedging effectiveness compared to Black–Scholes‐based deltas. The results encourage further exploration and application of the canonical approach to pricing and hedging derivatives. © 2007 Wiley Periodicals, Inc. Jnl Fut Mark 27: 771–790, 2007
Richardson extrapolation techniques for the pricing of American‐style options
Authors: Chang Chuang‐Chang , Chung San‐Lin , Stapleton Richard C. 
Published: June 2007

AbstractIn this article, the authors reexamine the American‐style option pricing formula of R. Geske and H.E. Johnson (1984), and extend the analysis by deriving a modified formula that can overcome the possibility of nonuniform convergence (which is likely to occur for nonstandard American options whose exercise boundary is discontinuous) encountered in the original Geske–Johnson methodology. Furthermore, they propose a numerical method, the Repeated‐Richardson extrapolation, which allows the estimation of the interval of true option values and the determination of the number of options needed for an approximation to achieve a given desired accuracy. Using simulation results, our modified Geske–Johnson formula is shown to be more accurate than the original Geske–Johnson formula for pricing American options, especially for nonstandard American options. This study also illustrates that the Repeated‐Richardson extrapolation approach can estimate the interval of true American option values extremely well. Finally, the authors investigate the possibility of combining the binomial Black–Scholes method proposed by M. Broadie and J.B. Detemple (1996) with the Repeated‐Richardson extrapolation technique. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 27:791–817, 2007
Influence of the surface structure of a multiblock copolymer on the cellular behavior of primary cell cultures of the upper aerodigestive tract in vitro
Authors: Rickert Dorothee , Franke R.‐P. , Lendlein A. , Kelch S. , Moses M.A. 
Published: June 2007

AbstractThe influence of the surface topography of a biodegradable copolymer on adhesion, proliferation, and cellular activity of primary cell cultures of the upper aerodigestive tract (ADT) was investigated. On the basis of the important functions of matrix metalloproteinases (MMPs) and their endogenous inhibitors, tissue inhibitor of MMPs (TIMPs) in regulating extracellular matrix remodeling, cellular adhesion and growth, the appearance and kinetics of these enzymes were investigated in primary cells of the upper ADT seeded on different surfaces of a polymeric biomaterial. Primary cell cultures of the upper ADT of Sprague‐Dawley rats were seeded on different surfaces (smooth versus rough surface) of a biodegradable multiblock copolymer and on polystyrene surface as control. Conditioned media of the primary cells were analyzed for MMPs and TIMPs by both zymography and radiometric enzyme assay. Cell adhesion and proliferation as well as the kinetics of appearance and activity level of MMP‐1, MMP‐2, and TIMPs were significantly different depending on the cell type and the surface structure of the multiblock copolymer. In this study, the data obtained indicated that surface topography governed the biological response to biomaterials. Knowledge as to how cells interact with the interface of biomaterials will be necessary in order to eventually design the “ideal” surface of biomaterials, which will be both tissue and organ‐optimized in order to best provide clinicians with specific and viable novel therapeutical options in medicine. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007