bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrodeposition of Metals for Micro‐ and Nanostructuring at Interfaces Between Solid, Liquid and Gaseous Conductors: Dendrites, Whiskers and Nanoparticles
Authors: Peppler Klaus , Poelleth Manuel , Meiss Sebastian , Rohnke Marcus , Janek Juergen 
Published: August 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Confinement Effects on Chemical Reactions — Toward an Integrated Rational Catalyst Design
Authors: Santiso Erik E. , Kostov Milen K. , George Aaron M. , Nardelli Marco Buongiorno , Gubbins Keith E. 
Published: August 2007

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract, please click on HTML or PDF.
Tumor lymphangiogenesis correlates with lymph node metastasis and clinicopathologic parameters in oral squamous cell carcinoma
Authors: Miyahara Mayumi , Tanuma Jun‐ichi , Sugihara Kazumasa , Semba Ichiro 
Published: August 2007

AbstractBACKGROUND.Lymphatic vessel density (LVD) and microvessel density (MVD) are important parameters for assessing the malignant potential of tumors and patient survival. In this report, the authors defined LVD as the density of D2‐40‐positive lymphatic vessels and MVD as the density of CD105‐positive microvessels per unit area of tissue. It was reported previously that vascular endothelial growth factor C (VEGF‐C) is a major modulator of LVD and MVD. The objectives of this study were to clarify the clinical and prognostic significance of both LVD and MVD in oral squamous cell carcinoma (OSCC) and to elucidate the lymphangiogenic and angiogenic activities of VEGF‐C in cancer tissues.METHODS.In total, 110 OSCC tissue samples were evaluated for LVD, MVD, and expression of VEGF‐C using immunohistochemistry. Correlations among these parameters and clinicopathologic factors were examined.RESULTS.LVD was significantly higher in tumors that had very high expression of VEGF‐C compared with tumors that had no/weak expression of VEGF‐C. LVD correlated well with lymph node metastasis (P < .001). MVD was correlated significantly with positive lymph node metastasis (P < .001) but not with VEGF‐C expression. In contrast, high expression of VEGF‐C was correlated significantly with advanced tumor status (P = .041). Survival rates were lower in patients who had higher LVD (P < .001), higher MVD (P = .0028), and strong VEGF‐C expression (P = .048).CONCLUSIONS.Lymphangiogenesis predominantly influenced metastasis‐free survival. The current results suggested that LVD is a more useful tool than MVD and VEGF‐C for deciding on therapeutic strategies in patients with OSCC. Cancer 2007. © 2007 American Cancer Society.
The Th1 immune response against HIV‐1 Gag p24‐derived peptides in mice expressing HLA‐A02.01 and HLA‐DR1
Authors: Pajot Anthony , Schnuriger Aurélie , Moris Arnaud , Rodallec Audrey , Ojcius David M. , Autran Brigitte , Lemonnier François A. , Lone Yu‐Chun 
Published: August 2007

AbstractUsing HLA‐DR1‐transgenic H‐2 class II knockout mice, we identified two new HLA‐DR1‐restricted HIV‐1 Gag p24‐derived epitopes (Gag321–340 and Gag331–350) and confirmed the immunogenicity of seven that have been previously described. The human relevance was confirmed for the two new ones (Gag321–340 and Gag331–350) assaying peripheral blood mononuclear cells from HLA‐DR1+ HIV‐1‐infected long‐term asymptomatic subjects and showing that Gag331–350 could prime CD4+ T cells from two HLA‐DR1+ HIV‐1 seronegative donors in vitro. Seven of these epitopes, structurally conserved among HIV‐1 clade B isolates, were selected for a comparative evaluation of their Th1 helper potential by immunizing HLA‐A02.01/HLA‐DR1‐transgenic, H‐2 class I/class II knockout mice with recombinant mouse invariant chain constructs in which each helper epitope was inserted in association with two reporter HIV‐1‐derived HLA‐A02.01‐restricted CD8+ T cell epitopes. A T helper effect was demonstrated in all cases, and was particularly strong with epitopes Gag301–320, Gag321–340 and Gag271–290, which should, therefore, be considered in the design of new vaccines.
Synthesis and Reactivity of 23‐tert‐Butyl‐ and 23‐Phenyltetraarylazuliporphyrins: an Analysis of the Effect of Bulky Substituents on Oxidative Ring Contractions to Benzocarbaporphyrins (Eur. J. Org. Chem. 24/2007)
Authors: El‐Beck Jessica A. , Lash Timothy D. 
Published: August 2007

AbstractThe cover picture shows the oxidative ring contraction of tetraphenylazuliporphyrins to give benzocarbaporphyrins. Bulky substituents on the azulene moiety influence the regioselectivity but do not inhibit this unusual chemistry. Details are discussed in the article by J. A. El‐Beck and T. D. Lash on p. 3981 ff.
Prediction of the median IDA curve by employing a limited number of ground motion records
Authors: Azarbakht Alireza , Dolšek Matjaž 
Published: August 2007

AbstractA methodology has been proposed which can be used to reduce the number of ground motion records needed for the reliable prediction of the median seismic response of structures by means of incremental dynamic analysis (IDA). This methodology is presently limited to predictions of the median IDA curve only. The reduction in the number of ground motion records needed to predict the median IDA curve is achieved by introducing a precedence list of ground motion records. The determination of such a list is an optimization problem, which is solved in the paper by means of (1) a genetic algorithm and (2) a proposed simple procedure. The seismic response of a simple, computationally non‐demanding structural model has been used as input data for the optimization problem. The presented example is a three‐storey‐reinforced concrete building, subjected to two sets of ground motion records, one a free‐field set and the other a near‐field set. It is shown that the median IDA curves can be predicted with acceptable accuracy by employing only four ground motion records instead of the 24 or 30 records, which are the total number of ground motion records for the free‐field and near‐field sets, respectively. Copyright © 2007 John Wiley & Sons, Ltd.
Key factors in the regulation of fetal and postnatal leydig cell development
Authors: Wu Xiufeng , Wan Shengqin , Lee Mary M. 
Published: August 2007

AbstractThe primary function of testicular Leydig cells is the production of androgens to promote sexual differentiation in the fetus, secondary sexual maturation at puberty, and spermatogenesis in the adult. The fetal and postnatal (adult) populations of Leydig cells differ morphologically and have distinct profiles of gene expression. As postnatal Leydig cells differentiate, they transition through three discrete maturational stages characterized by decreasing proliferative rate and increasing testosterone biosynthetic capacity. In this review, we discuss the development of both fetal and postnatal Leydig cells and review the regulation of this process by some of the key hormones and growth factors. J. Cell. Physiol. 213: 429–433, 2007. © 2007 Wiley‐Liss, Inc.
Isotope tracer investigations of natural products biosynthesis: the discovery of novel metabolic pathways
Authors: Mahmud Taifo 
Published: August 2007

AbstractFeeding experiments using isotopically labeled precursors remain crucial elements in the study of natural product biosynthesis. Through careful isotope tracer studies, a number of previously unrecognized biosynthetic pathways have now become obvious. One of the remarkable examples is the discovery of the non‐mevalonate pathway in plants, bacteria, algae, and plasmodium, whereas others include the discovery of a new shunt pathway that connects the mevalonate pathway and branched‐chain fatty acids in myxobacteria and the involvement of an unusual HMG‐CoA synthase‐like mechanism in polyketide biosynthesis. Significant progress has also been made in the biosynthetic studies of aminocyclitol‐derived natural products and other bioactive secondary metabolites. This review highlights some of the more recent discoveries of novel mechanisms and metabolic pathways involved in natural product biosynthesis based on isotope tracer experiments. Copyright © 2007 John Wiley & Sons, Ltd.
Effecting change in colleges and universities
Authors: Bruns Jeff W. , Bruns Diana L. 
Published: August 2007

AbstractInstitutional leaders often try to use theories to rethink or resolve organizational challenges. Bolman and Deal (2003) describe four organizational frames (structural, human resource, political, and symbolic) to understand and diagnose problems within any organization. A classic organizational challenge in higher education is the status quo or conservatism relating to change of faculty involvement in institutional decision making. Leaders in higher education recognize the need for change but are often uncertain how to facilitate it or lack an understanding of how to implement it. The use of multiple theoretical frameworks can assist leaders in diagnosing dilemmas and instigating change.
Separation of three water‐soluble vitamins by poly(dimethylsiloxane) microchannel electrophoresis with electrochemical detection
Authors: Li Xiang‐Yun , Zhang Qian‐Li , Lian Hong‐Zhen , Xu Jing‐Juan , Chen Hong‐Yuan 
Published: August 2007

AbstractA method for rapid separation and sensitive determination of three water‐soluble vitamins, pyridoxine, ascorbic acid (VC), and p‐aminobenzoic acid (PABA) has been developed by PDMS microchannel electrophoresis integrated with amperometric detection. After treatment of the microchip with oxygen plasma, the peak shapes of the three analytes were essentially improved. Pyridoxine, VC, and PABA were well separated within only 80 s in a running buffer of 20 mM borate solution (pH 8.5). Good linearity was obtained within the concentration range of 2–200 μM for the three water‐soluble vitamins. The detection limits were 1.0 μM for pyridoxine and VC, and 1.5 μM for PABA. The proposed method has been successfully applied to real human urine sample, without solid phase extraction, with recoveries of 80–122% for the three water‐soluble vitamins.
Double‐Grafted Cylindrical Brushes: Synthesis and Characterization of Poly(lauryl methacrylate) Brushes
Authors: Xu Youyong , Becker Harald , Yuan Jiayin , Burkhardt Markus , Zhang Yong , Walther Andreas , Bolisetty Sreenath , Ballauff Matthias , Müller Axel H. E. 
Published: August 2007

AbstractDouble‐grafted cylindrical brushes with poly(lauryl methacrylate) (PLMA) as the side chains were synthesized using the grafting‐from strategy via atom transfer radical polymerization (ATRP). The polyinitiator poly[2‐(2‐bromoisobutyryloxy)ethyl methacrylate] (PBIEM) with $\overline {DP} _{\rm n}$ = 240 and 1 500 served as the backbone. The PLMA side chains of the brushes carry long alkyl chains. GPC and 1H NMR measurements confirmed the successful formation of the PLMA cylindrical brushes. The side chains were cleaved from the cylindrical brushes by transesterification. GPC and 1H NMR results indicate that the initiating efficiency of the bromoester groups on the backbone for the bulky monomer was in the range of 0.34 ≤ f ≤ 0.67. Static and dynamic light scattering show that the ratio of the radius of gyration to the hydrodynamic radius, Rg/Rh, is in the range of 1.2–1.3, indicating that the LMA cylindrical brushes are semiflexible in solution. Atomic force microscopy (AFM) measurements show that short PLMA brushes exhibit a spherical morphology while the long brushes exhibit a worm‐like structure. DSC displayed melting peaks at around −30 °C, indicating the alkyl side chains of the PLMA chains in the double‐grafted cylindrical brushes are crystallizable.magnified image
Effects of Acceptors on the Electronic and Optoelectronic Properties of Fluorene‐Based Donor–Acceptor–Donor Copolymers
Authors: Lee Wen‐Ya , Cheng Kai‐Fang , Wang Then‐Fu , Chueh Chu‐Chen , Chen Wen‐Chang , Tuan Chih‐Shen , Lin Jen‐Lien 
Published: August 2007

AbstractIn this study, four fluorene‐based conjugated copolymers were synthesized to explore the acceptor effects on the electronic and optoelectronic properties. The studied polymers were poly{[2,7‐(9,9‐dihexylfluorene)]‐alt‐[2,2′:5,2″‐terthiophene]} (PFTT) and its derivatives of poly{[2,7‐(9,9′‐dihexylfluorene)]‐alt‐[2,3‐dimethyl‐5,7‐dithien‐2‐yl‐quinoxaline]} (PFDDTQ), poly{[2,7‐(9,9′‐dihexylfluorene)]‐alt‐[4,7‐dithien‐2‐yl‐2,1,3‐benzothiadiazole]} (PFDTBT), and poly{[2,7‐(9,9′‐dihexylfluorene)]‐alt‐[2,3‐dimethyl‐5,7‐dithien‐2‐yl‐thieno[3,4‐b]pyrazine]} (PFDDTTP) with the acceptors of quinoxaline (Q), 2,1,3‐benzothiadiazole (BT), and thieno[3,4‐b]pyrazine (TP), respectively. The order of the band gap was PFDTTP < PFDTBT < PFDDTQ < PFTT, which was on the reverse trend of emission maximum and field‐effect transistor (FET) mobility. The strong acceptor strength of the TP moiety and coplanar backbone in PFDTTP resulted in the highest intramolecular charge transfer (ICT) among the four polymers. The FET mobility of PFDTTP could be varied by two orders of magnitude through the solvent quality. The present study suggested the importance of the acceptor structure on the electronic and optoelectronic properties of semiconducting polymers.magnified image
Inclusion Complex Formation of Cellulose in NaOH–Thiourea Aqueous System at Low Temperature
Authors: Lue Ang , Zhang Lina , Ruan Dong 
Published: August 2007

AbstractIt is puzzling that cellulose could be dissolved rapidly in 9.5 wt.‐% NaOH/4.5 wt.‐% thiourea aqueous solution pre‐cooled to −5 °C, but it could not be dissolved in the same solvent mixture without prior cooling. To understand this phenomenon, changes in the structure and properties of NaOH and thiourea in water as well as solution behaviors of cellulose in the solvent at low temperatures were investigated by means of 13C NMR, Fourier transform infrared spectroscopy, wide‐angle X‐ray diffraction, transmission electron microscopy (TEM), and viscometry. The results indicated that an association of NaOH and thiourea in water through the hydrogen bonding strengthened with a decrease in temperature. The low temperature created a new hydrogen‐bonded network structure associated with NaOH, thiourea, water cluster, and cellulose, leading to the cleaving of the close chain packing of cellulose. The results proved that a good dispersion of cellulose occurred at a low temperature as a result of the formation of an inclusion complex (IC) hosted by thiourea and NaOH, in which cellulose chain associated with NaOH hydrates as guest was encaged. IC could aggregate to form a sphere having a mean size of 60–160 nm. TEM observations, for the first time, revealed the shape and size of IC and its aggregate. The stability of the cellulose solution could be related to the thiourea IC.magnified image
Application of FT Rheology to Industrial Linear and Branched Polyethylene Blends
Authors: Vittorias Iakovos , Wilhelm Manfred 
Published: August 2007

AbstractNumerous analytical techniques are used to quantify branching topologies in polyethylene. One of these methods, FT rheology, studies the higher harmonic contributions of the stress response to large amplitude oscillatory shear deformation. The sensitivity of FT rheology in the presence of sparse long‐chain branched chains blended with linear ones is addressed. FT rheology is sensitive even for small concentrations of a partly long‐chain branched component blended with a linear melt (1.5–5 wt.‐%). The non‐linear parameters present a strong dependence on the fraction of long‐chain branched species in a polydisperse melt, the miscibility of which is confirmed via rheological techniques.magnified image
A hyperbolic reaction–diffusion model for the hantavirus infection
Authors: Barbera E. , Currò C. , Valenti G. 
Published: August 2007

AbstractA hyperbolic reaction–diffusion model for the hantavirus infection, generalizing the parabolic set of equations recently derived by Abramson and Kenkre, is proposed within the context of Extended Thermodynamics. The model, as in the parabolic case, captures some of the realistic features of the dynamics of hantavirus in mice population, while it avoids the unphysical features concerning the instantaneous diffusive effects typical of parabolic equations. Traveling wave solutions, related to the spread of the infection in the landscape, are investigated. Both analytical and numerical results obtained herein are discussed and validated from the behavior of the biological system. Copyright © 2007 John Wiley & Sons, Ltd.
A study on the lumped preconditioner and memory requirements of FETI and related primal domain decomposition methods
Authors: Fragakis Yannis 
Published: August 2007

AbstractIn recent years, domain decomposition methods (DDMs) have emerged as advanced solvers in several areas of computational mechanics. In particular, during the last decade, in the area of solid and structural mechanics, they reached a considerable level of advancement and were shown to be more efficient than popular solvers, like advanced sparse direct solvers. The present contribution follows the lines of a series of recent publications on the relationship between primal and dual formulations of DDMs. In some of these papers, the effort to unify primal and dual methods led to a family of DDMs that was shown to be more efficient than the previous methods. The present paper extends this work, presenting a new family of related DDMs, thus enriching the theory of the relations between primal and dual methods, with the primal methods, which correspond to the dual DDM that uses the lumped preconditioner. The paper also compares the numerical performance of the new methods with that of the previous ones and focuses particularly on memory requirement issues related to the use of the lumped preconditioner, suggesting a particularly memory‐efficient formulation. Copyright © 2007 John Wiley & Sons, Ltd.
Rotational molding cycle time reduction through surface‐enhanced molds, Part B: Experimental study
Authors: Abdullah M.Z. , Bickerton S. , Bhattacharyya D. 
Published: August 2007

AbstractRotational molding is a process used to manufacture hollow plastic products, and has been heralded as a molding method with great potential. Because of long production cycle times, which are limited by the time required to heat‐up and cool‐down the mold and the product, its productivity is hampered. To address this issue, exterior mold modification techniques (i.e. the application of extended and rough surfaces) have been employed to enhance heat transfer to and from molds, ultimately reducing cycle times. Extended surfaces have the potential to enhance heat transfer by increasing the surface area. Roughness elements are utilized in conjunction with turbulent flows, also producing significant increases in heat transfer rates. Experimental results presented here demonstrate very significant cycle time reductions through the use of surface‐enhanced molds. The experimental savings are in the order of 18 and 28%, whereas the predicted cycle time reductions are around of 21 and 32% for roughness‐enhanced and pin‐enhanced molds, respectively. Although the prediction methods have been unable to forecast the exact experimental cycle times very accurately, they have proved to be useful for predicting the approximate cycle time reductions and the relative rankings of the plain and the surface‐enhanced molds. POLYM. ENG. SCI., 47:1420–1429, 2007. © 2007 Society of Plastics Engineers
Cis/trans configurations of the peptide CN bonds: isomerization and photoswitching
Authors: Micheau Jean‐Claude , Zhao Jianzhang 
Published: August 2007

AbstractCis/trans isomerization of peptide CN bonds is involved in the configurational changes and are definitive for the bioactivity of peptides and proteins. The basic molecular character and origin of the restricted rotation of the peptide CN bonds are briefly introduced, as well as the methods used for study of the cis/trans isomerization, such as the chymotrypsin‐coupled assay, pH‐mediated solvent jump, and UV‐resonance Raman spectroscopy, etc. The control of the peptide bond configuration with photoresponsive (photochromic) groups such as azobenzene or thioamide bonds is also reviewed. Copyright © 2007 John Wiley & Sons, Ltd.
Primary 1H/2H isotope effect in the NMR chemical shift of HClO4 salts of 1,8‐bis(dimethylamino)naphthalene derivatives
Authors: Chmielewski Piotr , Ozeryanskii Valery A. , Sobczyk Lucjan , Pozharskii Alexander F. 
Published: August 2007

AbstractThe primary 1H/2H isotope effect for a number of protonated naphthalene proton sponges (DMAN‐s) was measured and correlated with the δ(1H) value and IR spectroscopic characteristics of the [NHN]+ hydrogen bonds. A particular role of the unusual anharmonicity expressed in the isotopic ratio ISR ≫$\sqrt 2 $ is discussed when the fundamental vibrational levels are close to the barrier top for proton/deuteron motion. Copyright © 2007 John Wiley & Sons, Ltd.
Synthesis and structural study of 2′‐ and 2′,6′‐positioned methyl‐ and nitro‐substituted 3‐(arylhydrazono)pentane‐2,4‐diones
Authors: Marten Jan , Seichter Wilhelm , Weber Edwin , Böhme Uwe 
Published: August 2007

AbstractA systematic series of ortho‐methyl‐ and nitro‐substituted arylhydrazones 2–6 formed by Japp–Klingemann reaction between pentane‐2,4‐dione and the respective aryldiazonium salts have been synthesized and studied by X‐ray crystal structure analysis, with added quantum chemical calculations. The optimized molecular geometries based on DFT calculations, enabling determination of relevant rotational barriers, and the calculated bond and ring critical points, using the method of ‘atoms in molecules’, were found to correspond with the experimental data, involving specific molecular conformations and hydrogen‐bonded ring structure dependent on the ortho‐substitution, thus making possible reliable structural prediction of this compound class. Copyright © 2007 John Wiley & Sons, Ltd.
Transparent conducting antimony‐doped tin oxide films containing functionalized multi‐walled carbon nanotubes
Authors: Castro M. R. S. , Schmidt H. K. 
Published: August 2007

AbstractIn order to improve the conductivity of Sb:SnO2 (ATO) films, very thin multi‐walled carbon nanotubes (MWNTs) functionalized with –NH2 and –COOH groups have been investigated. The new nanocomposites were prepared by the addition of such MWNTs pre‐dispersed in a cationic surfactant (Hexadecyl‐trimethyl ammonium chloride) in the ATO sol at concentrations of 0.05 and 0.1 wt%. Coatings of pure ATO and nanocomposites were prepared by spin coating on borofloat glass substrates. Experiments show‐ ed that all coatings containing nanotubes present resistivities of the order of 10–1 to 10–2 Ω cm while pure ATO films prepared under the same conditions show resistivities which are about 16 times higher. Optical transmission in the visible range of all systems studied was about 90%. The results indicate the suitability of MWNTs as additives for enhancing electrical properties of transparent conductive coatings. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Landau–Zener theory for avoided crossings applied to the gallium–silane reactions
Authors: Pacheco‐Sánchez J. H. , Castillo S. , Luna‐García H. , Novaro O. 
Published: August 2007

AbstractLandau–Zener Theory for avoided crossings is applied here to obtain the transition probabilities (TPs) for the lowest Gallium–Silane excited states. Considering that silane orbits the gallium atom when the insertion angle θ is used as the reaction parameter, the translational energy is for this purpose irrelevant. The nonadiabatic TP depends on the angular velocity; hence, the inertia moment is more pertinent than the mass. Avoided crossings of the two lower A′ potential energy surfaces of Ga(2P,2S) + SiH4 interactions have to be taken into account. The TP of the excited system HGaSiH3 leading from one potential energy surface to another through an avoided crossing is then calculated. TPs for gallium–silane interaction are predicted using this novel approach. © 2007 Wiley Periodicals, Inc. Int J Quantum Chem, 2007