bluuebunny/crossref_metadata_2025_split huggingface dataset:
Toughening of nylon‐6 with epoxy‐functionalized acrylonitrile‐butadiene‐styrene copolymer
Authors: Sun S. L. , Tan Z. Y. , Xu X. F. , Zhou C. , Ao Y. H. , Zhang H. X. 
Published: June 2005

AbstractGlycidyl methacrylate (GMA) functionalized acrylonitrile‐butadiene‐styrene (ABS) copolymers have been prepared via an emulsion polymerization process. The epoxy‐functionalized ABS (e‐ABS) particles were used to toughen nylon‐6. Molau tests and FTIR results showed the reactions between nylon‐6 and e‐ABS have taken place. Scanning electron microscopy (SEM) displayed the compatibilization reaction between epoxy groups of e‐ABS and nylon‐6 chain ends (amine or carboxyl groups), which improve disperse morphology of e‐ABS in the nylon‐6 matrix. The presence of only a small amount of GMA (1 wt %) within the e‐ABS copolymer was sufficient to induce a pronounced improvement of the impact strength of nylon‐6 blends; whereas further increase of the GMA contents in e‐ABS resulted in lower impact strength because of the crosslinking reaction between nylon‐6 and e‐ABS, resulting in agglomeration of the ABS particles. SEM results showed shear yielding of the nylon‐6 matrix and cavitation of rubber particles were the major toughening mechanisms. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2170–2180, 2005
Study on correlation of morphology of electrospun products of polyacrylamide with ultrahigh molecular weight
Authors: Zhao Y. Y. , Yang Q. B. , Lu X. F. , Wang C. , Wei Y. 
Published: June 2005

AbstractPolyacrylamide (PAAm) with ultrahigh molecular weight of 9 × 106 g/mol has been processed by means of electrospinning, to afford products with a variety of morphologies, including polymer colloids, beaded fibers, smooth fibers, and ribbons. These morphologies can be controlled by a minute change of solution concentration in a small concentration range (0.3–3.0 wt %), because of the high molecular weight of the polymer. Under our experimental conditions, no electrospun product was obtained at the concentrations below 0.3 wt %. Beaded fibers and smooth fibers formed at the concentrations between 0.3 and 0.7 wt %. At concentrations between 0.7 and 2.0 wt %, smooth fibers and ribbons coexisted. At concentrations above 2.0 wt %, ribbons were the only product. Special morphologies such as triangular beads, helical fibers, and zigzag ribbons were also observed. With a lower molecular weight PAAm, branched fibers were found in the product. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2190–2195, 2005
Self‐organization and luminescent properties of nanostructured europium (III)–block copolymer complex thin films
Authors: Cong Yang , Fu Jun , Cheng Ziyong , Li Jian , Han Yanchun , Lin Jun 
Published: June 2005

AbstractWe introduce a simple method to create nanosized, ordered, and highly luminescent thin film of Eu (III)–block copolymer complex. Micelles of polystyrene–block‐poly(4‐vinylpyridine) (PS‐b‐P4VP) in P4VP‐selective solvents (ethanol/N,N‐dimethylformamide (DMF) mixture) serve as nanoreactors for the synthesis of Eu(III)–block copolymer complex with the presence of 1,10‐phenanthroline (Phen) as cooperative ligand. The resulted quaternary complexes were characterized by FT‐IR spectra,15N NMR spectra, and elemental analysis, indicative of a composition of Eu(III)–(PS‐b‐P4VP)–Phen–5DMF. Atomic force microscopy and transmission electron microscopy investigations reveal that the Eu(III)–(PS‐b‐P4VP)–Phen–5DMF complex can self‐organize into hexagonally ordered thin films when dip‐coated from the solution onto silicon or silica glass substrates. Such ordered thin films can emit red fluorescence of Eu3+with strong intensity and long lifetime. This method can be easily extended to prepare other ordered luminescent rare earth–polymer complexes thin films. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 2181–2189, 2005
Selected Effect of the Ions and the Neutrals in the Plasma Treatment of PTFE Surfaces: An OES‐AFM‐Contact Angle and XPS Study
Authors: Vandencasteele Nicolas , Fairbrother Howard , Reniers François 
Published: June 2005

AbstractSummary: Polytetrafluoroethylene (PTFE) surfaces were treated by oxygen and nitrogen species generated either in a remote (filtered) RF plasma or in an ion gun. In the first case, the majority of the species reaching the surface are neutral molecules, whereas in the second case, ions are the reactive agent. In this paper, we show that ions alone do not lead to a significant grafting of new functions on the PTFE surface. The XPS analysis of the treated surface show identical behaviour with oxygen and nitrogen ion treatment, and the evolution of the C1s peak shape suggest a progressive sputtering, leading to defluorination of the surface. The nitrogen plasma treatment lead to a subsequent grafting that is attributed mostly to the “excited neutrals”, but we suggest here that the ions could play a significant role in the activation process of the surface. The exposure of PTFE to an oxygen plasma lead to chemical etching of the surface, different from the physical sputtering induced by the ion treatment, that lead to a super‐hydrophobic behavior of the surface attributed to an increase in the surface roughness.
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Higher spins and stringy AdS5 × S5
Authors: Bianchi M. 
Published: June 2005

AbstractIn this lecture I review recent work done in collaboration with Beisert et al. [1‐3] (For a concise summary see [4].). After a notational flash on the AdS/CFT correspondence, I will discuss higher spin (HS) symmetry enhancement at small radius and how this is holographically captured by free N = 4 SYM theory. I will then derive the spectrum of perturbative superstring excitations on AdS in this particular limit and successfully compare it with the spectrum of single‐trace operators in free 𝒩 = 4 SYM at large N, obtained by means of Polya(kov)'s counting. Decomposing the spectrum into HS multiplets allows one to precisely identify the 'massless' HS doubleton and the lower spin Goldstone multiplets which participate in the pantagruelic Higgs mechanism, termed “La Grande Bouffe”. After recalling some basic features of Vasiliev's formulation of HS gauge theories, I will eventually sketch how to describe mass generation in the AdS bulk à la Sückelberg and its holographic implications such as the emergence of anomalous dimensions in the boundary 𝒩 = 4 SYM theory.
The SU(2) sector in AdS/CFT
Authors: Minahan J.A. 
Published: June 2005

AbstractIn the large N limit of 𝒩 = 4 Super Yang‐Mills,
the mixing under dilatations of the SU(2) sector, single trace
operators composed
of L complex scalar fields of two types,
is closed to all orders in perturbation theory.
By relying on the AdS/CFT correspondence, and by examining the currents for semiclassical strings,
we present evidence which implies that
there are small mixings that contradict the closure
of the SU(2) sector in the strong coupling limit.
These mixings first appear to second
order in the
λ/L2 expansion.
New aspects of 𝒩 = 2 theories
Authors: Gheerardyn J. 
Published: June 2005

AbstractWe review some recent observations in theories with eight supercharges. We point out that such theories can be generalized by starting from the equations of motion rather than from an action. We show that vector multiplets constructed in such a way can have more general Fayet‐Iliopoulos terms and that the scalar fields of hypermultiplets can be coordinate functions on more general target spaces. Although our discussion holds in five dimensions, the results can easily be extended to other dimensions.
New phases of thermal SYM and LST from Kaluza‐Klein black holes
Authors: Harmark T. , Obers N.A. 
Published: June 2005

AbstractWe review the recently found map that takes any static and neutral Kaluza‐Klein black hole, i.e. any static and neutral black hole on Minkowski‐space times a circle ℳ︁d × S1, and maps it to a corresponding solution for a non‐ and near‐extremal brane on a circle. This gives a precise connection between phases of Kaluza‐Klein black holes and the thermodynamic behavior of the non‐gravitational theories dual to near‐extremal branes on a circle. In particular, for the thermodynamics of strongly‐coupled supersymmetric Yang‐Mills theories on a circle we predict the existence of a new non‐uniform phase and find new information about the localized phase. We also find evidence for the existence of a new stable phase of (2,0) Little String Theory in the canonical ensemble for temperatures above its Hagedorn temperature.
Strings and D‐branes in holographic backgrounds
Authors: Israël D. 
Published: June 2005

AbstractWe review recent progress in the study of non‐rational (boundary) conformal field theories and their applications to describe exact holographic backgrounds in superstring theory. We focus mainly on the example of the supersymmetric coset SL(2, ℝ)/U(1), corresponding to the two‐dimensional black hole, and its dual N = 2 Liouville. In particular we discuss the modular properties of their characters, their partition function as well as the exact boundary states for their various D‐branes. Then these results are used to construct the corresponding quantities in the CFT of the NS5‐brane background, with applications to Little String Theories.
Non‐extremal instantons and wormholes in string theory
Authors: Bergshoeff E. , Collinucci A. , Gran U. , Roest D. , Vandoren S. 
Published: June 2005

AbstractWe construct the most general non‐extremal spherically symmetric
instanton solution of a gravity‐dilaton‐axion system with SL(2, R) symmetry,
for arbitrary euclidean spacetime dimension D≥ 3. A subclass of these
solutions
describe completely regular wormhole geometries, whose size is
determined by an invariant combination of the SL(2, R) charges.Our results can be applied to four‐dimensional effective actions of type II
strings compactified on a Calabi‐Yau manifold, and in particular to the
universal
hypermultiplet coupled to gravity. We show that these models contain
regular wormhole solutions, supported by regular
dilaton and RR scalar fields of the universal hypermultiplet.
On the thermodynamics of Gödel black holes
Authors: Klemm D. , Vanzo L. 
Published: June 2005

AbstractAfter a brief review of Gödel‐type universes in string theory, we discuss some intriguing properties of black holes immersed in such backgrounds. Among these are the upper bound on the entropy that points towards a finite‐dimensional Hilbert space of a holographically dual theory, and the minimum black hole temperature that is reminiscent of the Hawking‐Page transition. Furthermore, we discuss several difficulties that are encountered when one tries to formulate a consistent thermodynamics of Gödel black holes, and point out how they may be circumvented.
An extremal black hole from matrices
Authors: Toumbas N. 
Published: June 2005

AbstractWe study extremal charged black hole solutions in two dimensional type 0A string theory using the low energy effective gravity theory, and then attempt to identify them in the exact matrix model description of the theory. In particular, we identify a static Fermi sea configuration of matrix eigenvalues corresponding to a charged black hole, and derive some asymptotic properties of the black hole space‐time from the matrix model. We argue that the horizon of the black hole is replaced by the endpoint of th e Fermi surface.
Supergravity with Fayet‐Iliopoulos terms and R‐symmetry
Authors: Proeyen A. 
Published: June 2005

AbstractThe simplest examples of gauged supergravities are N = 1 or N = 2 theories with Fayet‐Iliopoulos (FI) terms. FI terms in supergravity imply that the R‐symmetry is gauged. Also the U(1) or SU(2) local symmetries of Kähler and quaternionic‐Kähler manifolds contribute to R‐symmetry gauge fields. This short review clarifies the relations.
Telomeres, cell senescence and human ageing
Authors: von Zglinicki Thomas , Martin‐Ruiz Carmen M. , Saretzki Gabriele 
Published: June 2005

AbstractTelomeres in most human cell types shorten during DNA replication in vitro because of various factors including the inability of DNA polymerases to fully copy the lagging strand, DNA end processing and random damage, often caused by oxidative stress. Short, uncapped telomeres activate replicative senescence, an irreversible cell cycle arrest and are thus a major cause of cell ageing in vitro. We will review how uncapped telomeres initiate a signalling cascade toward senescence, and why oxidative stress is a major cause of telomere shortening. Telomeres in most human cells shorten during ageing in vivo as well, suggesting two distinct possibilities. (1) Telomere shortening could be among the causes for ageing in vivo: Short telomeres might lead to senescence of (stem) cells in a tissue‐specific fashion, and this might contribute to age‐related functional attenuation in this tissue and even to systemic effects. Evidence for this is mostly indirect. (2) Telomere length could be a biomarker of ageing and age‐related morbidity: Short telomeres might indicate a history of high stress and damage in the individual and could thus act as risk markers for age‐related disease residing in a completely different tissue. There is evidence to support this possibility, although it is mostly correlative and is often derived from underpowered studies.
Prenatal diagnosis of echogenic lung: evolution and outcome
Authors: Illanes S. , Hunter A. , Evans M. , Cusick E. , Soothill P. 
Published: June 2005

AbstractObjectivesDespite the feasibility of detecting lung lesions by antenatal ultrasound, there are problems in correlating the prenatal diagnosis with the final histology and in predicting the outcome. In order to better describe these factors, we reviewed the outcome of fetuses that had been diagnosed with echogenic lung in a referral fetal medicine unit.MethodsWe searched the database of a tertiary fetal medicine unit for all cases of fetal echogenic lung seen since 1994 and studied the maternal and neonatal records found.ResultsThere were 48 cases of echogenic lung diagnosed at a median gestational age of 21 (range, 19–29) weeks, including 43 (90%) cases of congenital cystic adenomatoid malformation (CCAM) and 5 (10%) of pulmonary sequestration (PS). The evolution of the fetal abnormality after diagnosis was: in 22 (45.8%) cases the lesion disappeared; in 17 (35.5%) cases the lesion remained stable and six (12.5%) cases became severe. Three (6%) women underwent termination of pregnancy. The lesions were equally distributed between the two sides of the thorax. Mediastinal shift was associated with a threefold increase in the possibility of clinical deterioration (17% vs. 5%), and the disappearance of the lesion was twice as likely to occur when the lesion was classified as microcystic as when it was macrocystic (67% vs. 36%). Features of hydrops were found in 9 (21%) fetuses and in six (13%) cases progressed and resulted in intrauterine or neonatal death. Sixty‐four percent of cases with lesions that disappeared during the pregnancy had an abnormal computed tomography (CT) scan, and the prenatal diagnosis correlated with histology in 36% of these cases. Of the cases in which the lesions remained stable, 70.5% had an abnormal CT scan and the prenatal diagnosis correlated with the histology in 67% of the cases.ConclusionsPrenatally diagnosed echogenic lung has a good prognosis in the absence of hydrops. The ability to correctly assess echogenic lung lesions and the need for surgery by prenatal ultrasound is limited. Copyright © 2005 ISUOG. Published by John Wiley & Sons, Ltd.
Coordinate‐free kinematic analysis of overconstrained mechanisms with mobility one
Authors: Lerbet J. 
Published: June 2005

AbstractWe propose to analyse some classical overconstrained mechanisms by using explicitely the relations of singularity and not only the closure equation A1ˆ...ˆAn = e. Using the fact that their configuration space manifold is such that the constraint jacobian is permanently not of full rank, we apply our earlier developed analysis strategy for singularities to analyse overconstrained mechanisms. By theorem 1, the holonomic constraints A1ˆ...ˆAn = e are linearized and formulated in an appropriate form on the Lie algebra ... This gives a redundant set of linear equations which is solved. The used method is coordinate‐free and the solution of the Bennett and Bricard mechanisms is given as illustration of the method.
The transient response of a crack in a functionally graded strip under an in‐plane impact load
Authors: Li‐Cheng Guo , Lin‐Zhi Wu , Yu‐Guo Sun , Tao Zeng , Li‐Chen Wang 
Published: June 2005

AbstractThe transient response of a functionally graded strip with an embedded or edge crack perpendicular to the boundary is studied under an in‐plane impact load. By means of integral transform methods, the present problem is changed into a singular integral equation which can be solved numerically in the Laplace domain. It is found that the singular terms for the edge crack are different from those for the embedded crack. The influences of parameters such as the nonhomogeneity constant and the geometry parameters on the dynamic stress intensity factors (DSIFs) are studied.
U-series isochron dating of immature and mature calcretes as a basis for constructing Quaternary landform chronologies for the Sorbas basin, southeast Spain
Authors: Candy Ian , Black Stuart , Sellwood Bruce W. 
Published: June 2005

AbstractImmature and mature calcretes from an alluvial terrace sequence in the Sorbas basin, southeast Spain, were dated by the U-series isochron technique. The immature horizons consistently produced statistically reliable ages of high precision. The mature horizons typically produced statistically unreliable ages but, because of linear trends in the dataset and low errors associated with each data point, it was still possible to place a best-fit isochron through the dataset to produce an age with low associated uncertainties. It is, however, only possible to prove that these statistically unreliable ages have geochronological significance if multiple isochron ages are produced for a single site, and if these multiple ages are stratigraphically consistent. The geochronological significance of such ages can be further proven if at least one of the multiple ages is statistically reliable. By using this technique to date calcretes that have formed during terrace aggradation and at the terrace surface after terrace abandonment it is possible not only to date the timing of terrace aggradation but also to constrain the age at which the river switched from aggradation to incision. This approach, therefore, constrains the timing of changes in fluvial processes more reliably than any currently used geochronological procedure and is appropriate for dating terrace sequences in dryland regions worldwide, wherever calcrete horizons are present.
Investigating the potential spread of infectious diseases of sheep via agricultural shows in Great Britain
Authors: WEBB C. R. 
Published: June 2005

SUMMARYThe rate at which infectious diseases spread through farm animal populations depends both on individual disease characteristics and the opportunity for transmission via close contact. Data on the relationships affecting the contact structure of farm animal populations are, therefore, required to improve mathematical models for the spatial spread of farm animal diseases. This paper presents data on the contact network for agricultural shows in Great Britain, whereby a link between two shows occurs if they share common competitors in the sheep class. Using the network, the potential for disease spread through agricultural shows is investigated varying both the initial show infected and the infectious period of the disease. The analysis reveals a highly connected network such that diseases introduced early in the show season could present a risk to sheep at the majority of subsequent shows. This data emphasizes the importance of maintaining rigorous showground and farm-level bio-security.
Crohn's disease in people exposed to clinical cases of bovine paratuberculosis
Authors: JONES P. H. , FARVER T. B. , BEAMAN B. , ÇETINKAYA B. , MORGAN K. L. 
Published: June 2005

SUMMARYMycobacterium aviumsubspeciesparatuberculosis(Map), the cause of ruminant paratuberculosis, has been proposed as the causative agent of Crohn's disease. The objective of this study was to determine whether exposure to clinical cases of bovine paratuberculosis was a risk factor for Crohn's disease. A questionnaire was sent to dairy farmers living on premises where the occurrence or absence of clinical cases of bovine paratuberculosis had previously been determined. The prevalence of Crohn's disease was found to be similar to that reported in other studies in the United Kingdom and showed no association with bovine paratuberculosis. There was, however, a univariate association with geographical region. Ulcerative colitis showed univariate associations with age, frequency of contact with cattle and with smoking. The results do not support the hypothesis thatMapplays a causative role in the aetiology of Crohn's disease.
Contact rates and exposure to inter-species disease transmission in mountain ungulates
Authors: RICHOMME C. , GAUTHIER D. , FROMONT E. 
Published: June 2005

SUMMARYThe risk for a pathogen to cross the species barrier depends on the rate of efficient contacts between the species. However, contact rates between species have rarely been estimated from observations. Here we estimate contact rates and exposure of chamoisRupicapra rupicapraand Alpine ibexCapra ibexexposed to domestic pasteurellosis and brucellosis carried by sheep or cattle herds summering in mountain pastures. We use field observation data on animal positions treated in a geographic information system (GIS). Comparing 10 pastures, we show that the management of domestic herds influences the risk of inter-species transmission. Exposure to direct transmission of pasteurellosis is high when herds are not guarded nor enclosed, whereas exposure to indirect transmission of brucellosis is increased on epidemiological dangerous points such as salt deposits. Our preliminary results need further investigation, but they underline the importance of both herd management and pathogen transmission mode when the aim is to reduce the risk of contamination of wild populations by a pathogen associated with domestic pathogens.
Molecular epidemiology and diversity ofSalmonellaserovar Typhimurium in pigs using phenotypic and genotypic approaches
Authors: GEBREYES W. A. , ALTIER C. , THAKUR S. 
Published: June 2005

SUMMARYFor epidemiological investigations of the most common and non-host-adaptedSalmonellaserotypes, such as Typhimurium, highly discriminatory approaches are essential. In the present study, we evaluated three genotyping methods; amplified fragment length polymorphism (AFLP), pulsed-field gel electrophoresis (PFGE) and repetitive palindromic extragenic–PCR (Rep–PCR) using 40 isolates. AFLP showed the highest discriminatory index (0·939), resolution and throughput. To determine clonality ofSalmonellaTyphimurium isolates and epidemiological relatedness in different commercial pig production units, we employed AFLP in combination with antimicrobial resistance pattern and phage typing.Salmonellaserovar Typhimurium isolates (n=196) obtained from a longitudinal study of 18 pig farms over a 3-year period were studied. Using this approach, 16 distinct clonal types were identified. We found two common multidrug- resistant patterns including AmCmStSuTe and AmKmStSuTe. Two commonly multidrug- resistant phage types that are of known public health importance, DT104 and DT193, were also common. AFLP differentiated distinct clones within DT104, a phage type previously reported to be clonal. Fourteen of the clonal types were unique to one of the two production systems, showing diversity between independent commercial pig production systems located in the same geographical area. Clonal types obtained from nursery farms and corresponding finishing units were, however, similar.