bluuebunny/crossref_metadata_2025_split huggingface dataset:
Detecting low‐quality markers using map expanders
Authors: Ekstrøm Claus Thorn 
Published: October 2003

AbstractGenetic marker data play a crucial role in gene mapping, and genotyping errors may have substantial influence on the power to detect and the precision to locate disease loci. Statistical methods can identify individuals, markers, or pedigrees with a high likelihood of containing genotyping errors, and the putative erroneous genotypes can then be rechecked and either verified, removed, or corrected to reduce the loss of power introduced by errors. We present a method to identify genetic markers with a high genotyping error rate. Genotyping errors are likely to appear as double recombinations which expand the genetic map around the marker. Markers flagged as map expanders (i.e., having an excessive number of double recombinations) can then be reread or regenotyped, or a replacement marker of higher quality can be used instead. The proposed method can be applied to any type of pedigree. Simulation studies of nuclear pedigrees and sib‐pairs show that the proposed method generally has high power to identify map expanders when the set of markers is reasonably dense (average intermarker distance of 5 cM), even when the nominal genotyping error rate is low (2%). Not surprisingly, the power to detect map expanders increases with marker heterozygosity and genotyping error rate, and is reduced with increasing intermarker distance. When the method was applied to a real dataset consisting of 56 nuclear pedigrees genotyped for 20 microsatellite markers on chromosome 4, the method diagnosed three markers as map expanders. Subsequent examination of these markers proved that they all had high genotyping error frequencies. Genet Epidemiol 25:214–224, 2003. © 2003 Wiley‐Liss, Inc.
Surface Texture Design to Generate Specific Sizes and Shapes of UHMWPE Wear Particles
Authors: Fang H. W. , Hsu S. M. , Sengers J. V. 
Published: October 2003

AbstractOsteolysis induced by UHMWPE wear particles has emerged as the critical failure mechanism of artificial joints. However, the detailed mechanism of osteolysis and bone resoprtion induced by wear particles leading to the loosening of the total joint replacement is still not clear. To investigate the effects of size and shape of particles on biological response, particles with controlled size and shape are needed. The paper describes a novel technique where controlled size and shape of UHMWPE wear particles can be generated through rubbing against a textured surface. The basic principles of surface texturing to generate different size and shape of wear particles through rubbing have been developed. The surface features are fabricated through conventional semiconductor microfabrication techniques. Various designs were attempted and the results suggested that micro‐cutting mechanisms of a visco‐elastic material are complex but can be controlled through three dimensional surface features. Specific length of UHMWPE particles can be generated by controlling the cutting‐edge length of a surface wedge. The particle width can be controlled by the cutting‐edge height, normal load, and the sliding speed. With appropriate surface‐texture design, UHMWPE particles can be generated with desired sizes and shapes.
Scratch Resistance and Localised Damage Characteristics of Polymer Surfaces – a Review
Authors: Briscoe B. J. , Sinha S. K. 
Published: October 2003

AbstractThe “Scratch Test” is, arguably, the earliest and amongst the now most widely used techniques for evaluating a wide range of surface mechanical properties. Some of the areas where this test has been successfully used in the engineering field, both by research and industry, include the determination of the relative hardness of materials, characterizations of coatings, paints and thin‐films, modeling of the wear of materials and the estimation of different material deformation characteristics when subjected to hard asperity damage. In this paper we have reviewed the “state‐of‐the‐art” in the scratch method for polymeric materials. The paper provides some important theoretical models that have been developed in the field of scratching for material property characterizations. Results from different types of scratch tests (macro, micro and nano scales) on a range of polymeric materials are presented with critical discussion on the usefulness of each result. Finally, various areas for further research in scratching of polymer surfaces have been identified.
Reibungs‐ und Verschleißverhalten von randschichtmodifizierter HfO2‐verstärkter Al2O3‐Keramik im ungeschmierten Gleitkontakt
Authors: Schneider J. 
Published: October 2003

AbstractEine handelsübliche Aluminiumoxidkeramik wurde durch CO2‐lasergestütztes Umschmelzen und Einlegieren von Hafniumoxid mit unterschiedlichen Anteilen an Yttriumoxid gezielt oberflächenmodifiziert. In Folge der Laserbehandlung entstanden bis zu 400 μm dicke Randschichten mit einem mehrphasigen Gefüge, das durch eine Al2O3‐Matrix und eine feinlamellare, eutektische Reaktionsphase aus HfO2 und Al2O3 entlang der Kristallitgrenzen der Al2O3‐Matrix gekennzeichnet war. Das tribologische Verhalten der legierten Keramik wurde im ungeschmierten, reversierenden Gleitkontakt in Paarung mit Al2O3‐Kugeln bei Raumtemperatur und einer relativen Luftfeuchte von 50 % charakterisiert. Das Abrasivverschleißverhalten wurde unter furchender Beanspruchung durch SiC‐Abrasivpartikel untersucht. Das Reibungs‐ und Verschleißverhalten der lasermodifizierten Keramik wurde sowohl durch den Anteil als auch die Zusammensetzung des Legierungszusatzes beeinflusst. Die Untersuchungen zeigten für die randschichtmodifizierte Keramik im Vergleich zu einer kommerziell erhältlichen Al2O3‐Keramik bzw. Al2O3‐ZrO2‐Mischkeramik (ZTA) deutlich verbesserte tribologische Eigenschaften. Die Reibungszahl konnte verringert und der Verschleißwiderstand erhöht werden.
Effect of conversion from cyclosporine A to mizoribine on transplant arteriosclerosis in rat aortic allograft models
Authors: Shimizu Hisashi , Takahashi Masafumi , Takeda Shinichi , Tahara Kazunori , Inoue Seiichiro , Hakamata Yoji , Kaneko Takashi , Takeyoshi Izumi , Morishita Yasuo , Kobayashi Eiji 
Published: October 2003

AbstractRecent studies suggested that conversion from cyclosporine A (CsA) to antimetabolic agents protects allograft vasculopathy. However, the mechanism of this beneficial effect by the conversion therapy is not fully understood. In the present study, we investigated the effects of conversion from CsA to antimetabolic agent mizoribine (MZR) on the formation of transplant arteriosclerosis in rat aortic allografts. Conversion from CsA to MZR significantly prevented intimal hyperplasia and perivascular inflammatory cell infiltration at 28 days after aortic transplantation. These findings suggest that conversion therapy from CsA to antimetabolic agents might have therapeutic potential in transplant patients with chronic vascular rejection. © 2003 Wiley‐Liss, Inc. MICROSURGERY 23:454–457 2003
Light‐emitting diodes and lasers based on polymer films doped with small organic molecules and rare‐earth complexes
Authors: Díaz‐García María A. 
Published: October 2003

AbstractWe investigated the lasing properties of optically pumped polymer films. Amplified spontaneous emission (ASE) around 400 nm was observed in polymer films of polystyrene (PS) and poly(N‐vinylcarbazole) (PVK) doped up to 20% with the hole‐transporting organic molecule N,N′‐bis(3‐methylphenyl)‐N,N′‐diphenylbenzidine (TPD). Thus, TPD‐based films are candidates for blue‐emitting organic diode lasers. Films containing several semiconducting organic molecules and polymers and rare‐earth complexes were also investigated. Energy transfer was observed in PVK films doped with various europium and samarium complexes. PS films containing the electron‐transporting organic molecule 2‐(4‐biphenylyl)‐5‐(4‐tert‐butylphenyl)‐1,3,4‐oxadiazole and small amounts of TPD also showed energy transfer to the europium complexes, but not to the samarium ones. None of these films demonstrated ASE; therefore, they are not appropriate for lasing purposes. However, because rare‐earth ions have very sharp emission spectra, these materials are candidates for very monochromatic light‐emitting diodes. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2706–2714, 2003
Organic light‐emitting diodes with multiple photocrosslinkable hole‐transport layers
Authors: Domercq Benoit , Hreha Richard D. , Zhang Ya‐Dong , Haldi Andreas , Barlow Stephen , Marder Seth R. , Kippelen Bernard 
Published: October 2003

AbstractWe report on photocrosslinkable hole‐transport polymers and their use as photodefinable hole‐transport layers in organic light‐emitting diodes. The polymers were obtained by copolymerization of bis(diarylamino)biphenyl‐based acrylate monomers with cinnamate‐functionalized acrylate moieties. Polymers with a range of redox potentials were obtained by varying the substitution patterns of the bis(diarylamino)biphenyl units. The 2 + 2 cycloaddition of the cinnamate moieties following UV irradiation renders the material insoluble. This allows for patterning of the polymer and simultaneously enables the fabrication of multilayer structures from solution. Hole mobilities were measured in these copolymers with the time‐of‐flight technique. Their performance as hole‐transport layers in light‐emitting diodes, with tris(8‐hydroxyquinolinato)aluminum as the emitter and electron‐transport layer, is evaluated. Electroluminescent devices with multiple hole‐transport layers having different ionization potentials were fabricated from solution, and the quantum efficiency of these devices was greater than that for devices based on a single hole‐transport layer. © 2003 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 41: 2726–2732, 2003
Temperature dependence of19F NMR and ion transport parameters of fluoride ion conductors SnF2—PbF2and 2SnF2—NH4F prepared by mechanical milling
Authors: Kumar M. , Yamada K. , Okuda T. , Sekhon S. S. 
Published: October 2003

Abstract19F NMR studies have been carried out on mixed metal fluorides composed of SnF2—PbF2and 2SnF2—NH4F and prepared by mechanical milling. Motional narrowing observed in the variation of19F NMR linewidth as a function of temperature for both the systems suggests the occurrence of F−ion diffusion. The variation of different ion transport parameters calculated from NMR results like jump frequency, diffusion coefficient, and conductivity with temperature has been found to be closely related with experimentally measured conductivity results.
Cation distribution and magnetic properties of natural chromites
Authors: Rais A. , Yousif A. A. , Al‐shihi M. H. , Al‐rawas A. D. , Gismelseed A. M. , El‐zain M. E. 
Published: October 2003

AbstractTen specimens of chromites from Oman ophiolites have been studied using magnetic susceptibility χ measurements, Mössbauer spectroscopy (MS), Scanning electron microscopy (SEM), and X‐ray diffraction (XRD). XRD shows that all samples have a face‐centered cubic spinel structure. MS analysis and SEM data at room temperature enabled to derive the chemical formula and the cations distribution among tetrahedral (A1 and A2) and octahedral (B) sites. For all specimens, paramagnetic variations of 1/χ with the temperature T show a systematic curve bending at a critical temperature T0, which indicates a change of the effective paramagnetic moment μeff. This deviation from Curie–Weiss law is interpreted as due to spin inversion of a fraction δ of Cr3+ cations located in the octahedral sites of the spinel structure. This interpretation is supported by a decrease in the Mössbauer peak areas of Fe2+ located in A1 sites from 300 to 80 K at the expense of Fe2+ located in A2 sites. The values of δ and μeff for each specimen are calculated by fitting this model separately to the experimental 1/χ versus T above and below T0.
The effect of a nonmagnetic cap layer on the spin‐polarized tunneling and magnetoresistance in double‐barrier planar junctions
Authors: Xie Zheng‐wei , Li Bo‐zang , Li Yu‐xian 
Published: October 2003

AbstractWithin the framework of the free‐electron model, the tunneling magnetoresistance (TMR) and tunneling conductance (TC) in double magnetic tunnel junctions (DMTJ) with nonmagnetic cap layer, i.e. the NM/FM/I/NM/(FM)/I/FM/NM junction is investigated. FM, NM and I represent the ferromagnetic metal, nonmagnetic metal and insulator, respectively, NM(FM) indicates that the middle layer can be NM or FM. Our results show that, due to the spin‐dependent interfacial potential barriers, the influences of the thickness of the FM layer on TC and TMR in DMTJ are large, and when the thicknesses of these two FM layers are suitable a large TMR can be obtained. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Prospects for carrier‐mediated ferromagnetism in GaN
Authors: Graf Tobias , Goennenwein Sebastian T. B. , Brandt Martin S. 
Published: October 2003

AbstractTheoretical predictions of room‐temperature ferromagnetism in Mn‐doped GaN and other wide band gap semiconductors suggest that these materials might be useful for spintronic applications. In this short review, we summarize recent observations on the gap states of GaN:Mn, which make it impossible that the two main prerequisites of these predictions can be fulfilled at the same time, which are (1) a large concentration of localized Mn2+ spins coexisting with (2) a high density of free holes in the valence band. Such conditions have been observed in only a few materials like e.g. GaAs:Mn. More typically, transition‐metal impurities act as traps for free carriers, thus pinning the Fermi level in the semiconductor band gap far from the valence or conduction band. Alternatively to ferromagnetism mediated by free carriers, the interactions between bound magnetic polarons and the double‐exchange mechanism have been suggested to possibly lead to ferromagnetism in GaN:Mn. Because of the energy position and the character of its gap states, Mn seems to be rather unsuitable for these two mechanisms. Better candidates would be GaN:Fe:Mg for a system of magnetic polarons, and GaN:Cr for a double‐exchange ferromagnet. Because of its short‐range nature, the double‐exchange interaction requires rather concentrated alloys and does not offer significant advantages of GaN:Mn over the established ferromagnetic materials. However, microscopic ferromagnetic inclusions observed in many SQUID measurements of GaN:Mn could possibly help to achieve spin injection in nitride semiconductors. (© 2003 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Convergence of biological and psychological perspectives on cognitive coordination in schizophrenia
Authors: Phillips William A. , Silverstein Steven M. 
Published: October 2003

AbstractThe concept of locally specialized functions dominates research on higher brain function and its disorders. Locally specialized functions must be complemented by processes that coordinate those functions, however, and impairment of coordinating processes may be central to some psychotic conditions. Evidence for processes that coordinate activity is provided by neurobiological and psychological studies of contextual disambiguation and dynamic grouping. Mechanisms by which this important class of cognitive functions could be achieved include those long-range connections within and between cortical regions that activate synaptic channels via NMDA-receptors, and which control gain through their voltage-dependent mode of operation. An impairment of these mechanisms is central to PCP-psychosis, and the cognitive capabilities that they could provide are impaired in some forms of schizophrenia. We conclude that impaired cognitive coordination due to reduced ion flow through NMDA-channels is involved in schizophrenia, and we suggest that it may also be involved in other disorders. This perspective suggests several ways in which further research could enhance our understanding of cognitive coordination, its neural basis, and its relevance to psychopathology.
Perceptual objects may have nonphysical properties
Authors: Ben-Ze’ev Aaron 
Published: October 2003

AbstractByrne & Hilbert defend color realism, which assumes that: (a) colors are properties of objects; (b) these objects are physical; hence, (c) colors are physical properties. I accept (a), agree that in a certain sense (b) can be defended, but reject (c). Colors are properties of perceptual objects – which also have underlying physical properties – but they are not physical properties.
Perceptual variation, realism, and relativization, or: How I learned to stop worrying and love variations in color vision
Authors: Cohen Jonathan 
Published: October 2003

AbstractIn many cases of variation in color vision, there is no nonarbitrary way of choosing between variants. Byrne & Hilbert insist that there is an unknown standard for choosing, whereas eliminativists claim that all the variants are erroneous. A better response relativizes colors to perceivers, thereby providing a color realism that avoids the need to choose between variants.
Schizophrenic cognition: Taken out of context?
Authors: Hemsley David R. 
Published: October 2003

AbstractThis commentary addresses: (a) the problems of definition which have been prominent in the use of the term context in schizophrenia research; (b) potentially useful distinctions and links with other theories of schizophrenic cognition; and (c) possible pathways to schizophrenic symptoms. It is suggested that at least two major aspects of the operation of context may be distinguished and that both may be impaired in schizophrenia.
Why not color physicalism without color absolutism?
Authors: Jakab Zoltán , McLaughlin Brian P. 
Published: October 2003

AbstractWe make three points. First, the concept of productance value that the authors propose in their defense of color physicalism fails to do the work for which it is intended. Second, the authors fail to offer an adequate physicalist account of what they call the hue-magnitudes. Third, their answer to the problem of individual differences faces serious difficulties.
Context, connection, and coordination: The need to switch
Authors: Oades Robert D. , Röpcke Bernd , Oknina Ljubov 
Published: October 2003

AbstractContext, connection, and coordination (CCC) describe well where the problems that apply to thought-disordered patients with schizophrenia lie. But they may be part of the experience of those with other symptom constellations. Switching is an important mechanism to allow context to be applied appropriately to changing circumstances. In some cases, NMDA-voltage modulations may be central, but gain and shift are also functions that monoaminergic systems express in CCC.
Clarifying the problem of color realism
Authors: Maund Barry 
Published: October 2003

Abstract“The problem of color realism” as defined in the first section of the target article, is crucial to the argument laid out by Byrne & Hilbert. They claim that the problem of color realism “does not concern, at least in the first instance, color language or color concepts” (sect. 1.1). I argue that this claim is misconceived and that a different characterisation of the problem, and some of their preliminary assumptions makes their positive proposal less appealing.
Can a physicalist notion of color provide any insight into the nature of color perception?
Authors: Mausfeld Rainer , Niederée Reinhard 
Published: October 2003

AbstractByrne & Hilbert (B&H) conceive of color perception as the representation of a physical property “out there.” In our view, their approach does not only have various internal problems, but is also apt to becloud both the intricate and still poorly understood role that “color” plays within perceptual architecture, and the complex coupling to the “external world” of the perceptual system as an entirety. We propose an alternative perspective, which avoids B&H's misleading dichotomy between a purely subjective and a realist conception of “color.”
Color realism and color illusions
Authors: Todorovic Dejan 
Published: October 2003

AbstractAs demonstrated by several example displays, color illusions challenge color realism, because they involve a one-to-many reflectance-to-color mapping. Solving this problem by differentiating between veridical and illusory colors corresponding to the same reflectance is hampered because of the lack of an appropriate criterion. However, the difference between veridical and illusory color perception can still be maintained.
A QUEUE WITH POSITIVE AND NEGATIVE ARRIVALS GOVERNED BY A
MARKOV CHAIN
Authors: Shin Yang Woo , Choi Bong Dae 
Published: October 2003

We consider a single-server queue with exponential service
time and two types of arrivals: positive and negative. Positive
customers are regular ones who form a queue and a negative arrival
has the effect of removing a positive customer in the system.
In many applications, it might be more appropriate to assume
the dependence between positive arrival and negative arrival.
In order to reflect the dependence, we assume that the positive
arrivals and negative arrivals are governed by a finite-state
Markov chain with two absorbing states, say 0 and 0′. The
epoch of absorption to the states 0 and 0′ corresponds to
an arrival of positive and negative customers, respectively. The
Markov chain is then instantly restarted in a transient state,
where the selection of the new state is allowed to depend on the
state from which absorption occurred.The Laplace–Stieltjes transforms (LSTs) of the sojourn
time distribution of a customer, jointly with the probability
that the customer completes his service without being removed,
are derived under the combinations of service disciplines FCFS
and LCFS and the removal strategies RCE and RCH. The service
distribution of phase type is also considered.
Neural mechanisms of sexual imprinting
Authors: Bischof Hans-Joachim 
Published: October 2003

AbstractSexual imprinting is an early learning process by which a young animal acquires information which will help in choosing a sexual partner. It consists of two separate phases, an acquisition phase where features of the social environment are learnt, and a stabilisation phase in which, guided by the previously acquired social information, a preference for a sexual partner is established and stabilised, such that it cannot be altered subsequently. The stabilisation process is short and can be controlled experimentally. This review summarises research on the neural events accompanying consolidation in those brain areas which have previously been identified as important for imprinting. It shows that the period during which consolidation can occur can be shifted only within a certain time window, and demonstrates the fast adjustment of spine densities within the imprinting areas after consolidation has started. It further suggests that long term potentiation (LTP) and long term depression (LTD)-like mechanisms may be involved in this learning process, and that the immediate early genes ZENK and c-fos are expressed within the relevant imprinting areas in the course of consolidation. Evidence is presented for a prominent role of the lateral neostriatum in the imprinting process, and also for the involvement of the hippocampus in this type of early learning.