bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laser Processing of Advanced Bioceramics
Authors: Narayan R. J. , Jin C. , Doraiswamy A. , Mihailescu I. N. , Jelinek M. , Ovsianikov A. , Chichkov B. , Chrisey D. B. 
Published: January 2006

AbstractIn this article, laser processing of diamondlike carbon‐metal nanocomposite films, hydroxyapatite‐osteoblast composites, and Ormocer® microdevices for medical applications is described. Pulsed laser deposition has been used to process diamondlike carbon‐silver‐platinum nanocomposite films that provide hardness, wear resistance, corrosion resistance, and antimicrobial functionalities to cardiovascular, orthopaedic, biosensor, and MEMS devices. Laser direct writing has been used for fabricating integrated cell‐scaffold structures. Two photon induced polymerization has been used to create Ormocer® tissue engineering scaffolds and microneedles with unique geometries. Pulsed laser deposition, laser direct write, and two photon induced polymerization techniques may provide medical engineers with advanced biomaterials that possess unique structures and functionalities.
Mechanical Behavior of Multilayered Nanoscale Metal‐Ceramic Composites
Authors: Deng X. , Chawla N. , Chawla K. K. , Koopman M. , Chu J. P. 
Published: January 2006

AbstractSingle and multilayered structures at nano‐length scale are very attractive materials due to their high strength, toughness, and wear resistance relative to conventional laminated composites. In this study, single layered Al, SiC, and multilayered Al/SiC composites were synthesized by DC/RF magnetron sputtering. The microstructure of the multilayered structures was characterized by scanning electron microscopy (SEM). The elastic and plastic behavior of single and multilayered materials was investigated by nanoindentation and tensile testing. For nanoindentation, an analytical model was employed to subtract the contribution of the Si substrate, in order to extract the true modulus of the films. Finite element simulations were employed to confirm the analytical predictions and to investigate the anisotropic elastic behavior of the multilayered composite. It was concluded that while indentation provides reasonable Young's modulus and hardness values in monolithic layers, it does not provide the true modulus of the multilayered materials because of their inherent anisotropy.
Cover Picture: Laser Processing of Advanced Bioceramics (Adv. Eng. Mater. 12/2005)
Authors: Narayan R. J. , Jin C. , Doraiswamy A. , Mihailescu I. N. , Jelinek M. , Ovsianikov A. , Chichkov B. , Chrisey D. B. 
Published: January 2006

AbstractIn this article, laser processing of diamondlike carbon‐metal nanocomposite films, hydroxyapatite‐osteoblast composites, and Ormocer® microdevices for medical applications is described. Pulsed laser deposition has been used to process diamondlike carbon‐silver‐platinum nanocomposite films that provide hardness, wear resistance, corrosion resistance, and antimicrobial functionalities to cardiovascular, orthopaedic, biosensor, and MEMS devices. Laser direct writing has been used for fabricating integrated cell‐scaffold structures. Two photon induced polymerization has been used to create Ormocer® tissue engineering scaffolds and microneedles with unique geometries. Pulsed laser deposition, laser direct write, and two photon induced polymerization techniques may provide medical engineers with advanced biomaterials that possess unique structures and functionalities.
General friction theory viscosity model for the PC‐SAFT equation of state
Authors: Quiñones‐Cisneros Sergio E. , Zéberg‐Mikkelsen Claus K. , Fernández Josefa , García Josefa 
Published: January 2006

AbstractIn this work, a general f‐theory viscosity model based on the perturbed‐chain statistical associating fluid theory (PC‐SAFT) equation of state (EoS) has been developed for the description of the viscosity behavior of the normal alkanes family (from methane to n‐octadecane). This general f‐theory model has been shown to provide satisfactory results for the modeling of the viscosity of the normal alkanes as well as carbon dioxide and nitrogen over wide ranges of temperatures and up to 100 MPa. In addition, using simple mixing rules, an evaluation of the model performance has been carried out for several n‐alkane and carbon dioxide + n‐alkane mixtures over wide ranges of temperature and pressure. The chosen mixing rules provide good mixture viscosity prediction, close to or within experimental uncertainty, which is satisfactory for most applications (industrial and research). Further, the combination of the PC‐SAFT EoS with the f‐theory adds one more thermophysical property to the list of properties for which this model already delivers an improved representation, making the application potential for the PC‐SAFT EoS even wider. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Real‐time estimation of food defrosting by software sensors
Authors: Akkari E. , Chevallier S. , Boillereaux L. 
Published: January 2006

AbstractSoftware sensors (or observers) are especially useful when the state vector of a system cannot be measured. Widely employed for bioprocesses, they estimate the state variables from available measurements, which are functions of one or several state variables, provided that the observability property is checked. In food defrosting, an important challenge is to know the spread of the melting front inside the product, without any invasive measurement. The solution proposed in this paper is based on the design of software sensors able to estimate, from a superficial temperature measurement, the temperature distribution in the product, in real time, and consequently making it possible to determine the melting zone. The proposed solutions are, first, an extended Kalman Filter and, second, switched reduced Luenberger observers. The results are illustrated during the experimental thawing of a block of tylose in forced convection. © 2006 American Institute of Chemical Engineers AIChE J, 2006
Cortical network for representing the teeth and tongue in primates
Authors: Kaas Jon H. , Qi Hui‐Xin , Iyengar Soumya 
Published: January 2006

AbstractSensory information from the tongue and teeth is used to evaluate and distinguish food and nonfood items in the mouth, reject some and masticate and swallow others. While it is known that primates have a complex array of 10 or more somatosensory areas that contribute to the analysis of sensory information from the hand, less is known about what cortical areas are involved in processing information from receptors of the tongue and teeth. The tongue contains taste receptors, as well as mechanoreceptors. Afferents from taste receptors and mechanoreceptors of the tongue access different ascending systems in the brainstem. However, it is uncertain how these two sources of information are processed in cortex. Here the parts of somatosensory areas 3b, 3a, and presumptive 1 that represent the mechanoreceptors of the teeth and tongue are identified, and evidence is presented that the representations of the tongue also get information from the taste nucleus of the thalamus, VPMpc. As areas 3b, 3a, and 1 project to other areas of somatosensory cortex, and those areas to additional areas, some or all of the currently defined somatosensory areas of cortex may be involved in processing gustatory, as well as tactile, information from the tongue and thus have a role in the biologically important function of evaluating food in the mouth. © 2006 Wiley‐Liss, Inc.
Imaging, anatomical, and molecular analysis of callosal formation in the developing human fetal brain
Authors: Ren Tianbo , Anderson Aurora , Shen Wei‐Bin , Huang Hao , Plachez Celine , Zhang Jiangyang , Mori Susumu , Kinsman Stephen L. , Richards Linda J. 
Published: January 2006

AbstractA complex set of axonal guidance mechanisms are utilized by axons to locate and innervate their targets. In the developing mouse forebrain, we previously described several midline glial populations as well as various guidance molecules that regulate the formation of the corpus callosum. Since agenesis of the corpus callosum is associated with over 50 different human congenital syndromes, we wanted to investigate whether these same mechanisms also operate during human callosal development. Here we analyze midline glial and commissural development in human fetal brains ranging from 13 to 20 weeks of gestation using both diffusion tensor magnetic resonance imaging and immunohistochemistry. Through our combined radiological and histological studies, we demonstrate the morphological development of multiple forebrain commissures/decussations, including the corpus callosum, anterior commissure, hippocampal commissure, and the optic chiasm. Histological analyses demonstrated that all the midline glial populations previously described in mouse, as well as structures analogous to the subcallosal sling and cingulate pioneering axons, that mediate callosal axon guidance in mouse, are also present during human brain development. Finally, by Northern blot analysis, we have identified that molecules involved in mouse callosal development, including Slit, Robo, Netrin1, DCC, Nfia, Emx1, and GAP‐43, are all expressed in human fetal brain. These data suggest that similar mechanisms and molecules required for midline commissure formation operate during both mouse and human brain development. Thus, the mouse is an excellent model system for studying normal and pathological commissural formation in human brain development. © 2006 Wiley‐Liss, Inc.
Whisker maps in marsupials: Nerve lesions and critical periods
Authors: Waite Phil M.E. , Gorrie Catherine A. , Herath Nimali P. , Marotte Lauren R. 
Published: January 2006

AbstractIn the wallaby, whisker‐related patterns develop over a protracted period of postnatal maturation in the pouch. Afferents arrive simultaneously in the thalamus and cortex from postnatal day (P) 15. Whisker‐related patterns are first seen in the thalamus at P50 and are well formed by P73, before cortical patterns first appear (P75) or are well developed (P85). This study used the slow developmental sequence and accessibility of the pouch young to investigate the effect of nerve lesions before afferent arrival, or at times when thalamic patterns are obvious but cortical patterns not yet formed. The left infraorbital nerve supplying the whiskers was cut at P0–93 and animals were perfused at P112–123. Sections through the thalamus (horizontal plane) and cortex (tangential) were reacted for cytochrome oxidase to visualize whisker‐related patterns. Lesions of the nerve at P2–5, before innervation of the thalamus or cortex, resulted in an absence of patterns at both levels. Lesions from P66–77 also disrupted thalamic and cortical patterns, despite the fact that thalamic patterns are normally well established by P73. Lesions from P82–93 resulted in normal thalamic and cortical patterns. Thus, despite the wallaby having clearly separated times for the development of patterns at different levels of the pathway, these results suggest a single critical period for the thalamus and cortex, coincident with the maturation of the cortical pattern. Possible mechanisms underpinning this critical period could include dependence of the thalamic pattern on corticothalamic activity or peripheral signals to allow consolidation of thalamic barreloids. © 2006 Wiley‐Liss, Inc.
Connecting thalamus and cortex: The role of ephrins
Authors: Uziel Daniela , Garcez Patricia , Lent Roberto , Peuckert Christiane , Niehage Ronny , Weth Franco , Bolz Jürgen 
Published: January 2006

AbstractThe complex task of wiring up the brain during embryonic development is achieved by a multitude of guidance signals acting in complex combinations to drive growing axons to their proper targets. The somatosensory system provides an extensively studied model system featuring many universal mechanisms of neural development. In rodents, it constitutes an important model to study how precise topographic connections are achieved. Recent evidence suggests that the Eph/ephrin family of guidance molecules is of pivotal importance for the development of the somatosensory system. Members of Eph/ephrin family are thought to be involved in the global presorting of thalamic axons projecting to the cortex, in labeling specific cortical areas for innervation, in providing topographic cues within the target area, and in distinguishing cortical layers for intracortical wiring. The Eph/ephrin system also seems to contribute to the formation of specific corticothalamic feedback projections. So far, the functions of only a few members of the Eph/ephrin family have been examined, but expression analysis indicates complex combinatorial effects of these signaling molecules. Understanding the Eph/ephrin wiring code is expected to yield new insights into the development and plasticity of brain circuits involved in higher functions. © 2006 Wiley‐Liss, Inc.
Evaluating China's university library Web sites using correspondence analysis
Authors: Shen Xiangxing , Li Dongmin , Shen Chong 
Published: January 2006

AbstractIn recent years, many evaluations of Web sites have been conducted, and relevant researches have also been carried out in academic circles. Correspondence analysis is introduced in this paper to evaluate university library Web sites through building a correspondence analysis model. This paper gives suggestions as to how to construct university library Web sites based on analysis and summary of evaluation results, in a bid to strengthen the construction of university library Web sites.
Understanding consumer trust in Internet shopping: A multidisciplinary approach
Authors: Cheung Christy M.K. , Lee Matthew K.O. 
Published: January 2006

AbstractThe importance of trust in building and maintaining consumer relationships in the online environment is widely accepted in the Information Systems literature. A key challenge for researchers is to identify antecedent variables that engender consumer trust in Internet shopping. This paper adopts a multidisciplinary approach and develops an integrative model of consumer trust in Internet shopping through synthesizing the three diverse trust literatures. The social psychological perspective guides us to include perceived trustworthiness of Internet merchants as the key determinant of consumer trust in Internet shopping. The sociological viewpoint suggests the inclusion of legal framework and third‐party recognition in the research model. The views of personality theorists postulate a direct effect of propensity to trust on consumer trust in Internet shopping. The results of this study provide strong support for the research model and research hypotheses, and the high explanatory power illustrates the complementarity of the three streams of research on trust. This paper contributes to the conceptual and empirical understanding of consumer trust in Internet shopping. Implications of this study are noteworthy for both researchers and practitioners.
How much of it is real? Analysis of paid placement in Web search engine results
Authors: Nicholson Scott , Sierra Tito , Eseryel U. Yeliz , Park Ji‐Hong , Barkow Philip , Pozo Erika J. , Ward Jane 
Published: January 2006

AbstractMost Web search tools integrate sponsored results with results from their internal editorial database in providing results to users. The goal of this research is to get a better idea of how much of the screen real estate displays “real” editorial results as compared to sponsored results. The overall average results are that 40% of all results presented on the first screen are “real” results, and when the entire first Web page is considered, 67% of the results are nonsponsored results. For general search tools such as Google, 56% of the first screen and 82% of the first Web page contain nonsponsored results. Other results include that query structure makes a significant difference in the percentage of nonsponsored results returned by a search. Similarly, the topic of the query also can have a significant effect on the percentage of sponsored results displayed by most Web search tools.
Query expansion behavior within a thesaurus‐enhanced search environment: A user‐centered evaluation
Authors: Shiri Ali , Revie Crawford 
Published: January 2006

AbstractThe study reported here investigated the query expansion behavior of end‐users interacting with a thesaurus‐enhanced search system on the Web. Two groups, namely academic staff and postgraduate students, were recruited into this study. Data were collected from 90 searches performed by 30 users using the OVID interface to the CAB abstracts database. Data‐gathering techniques included questionnaires, screen capturing software, and interviews. The results presented here relate to issues of search‐topic and search‐term characteristics, number and types of expanded queries, usefulness of thesaurus terms, and behavioral differences between academic staff and postgraduate students in their interaction. The key conclusions drawn were that (a) academic staff chose more narrow and synonymous terms than did postgraduate students, who generally selected broader and related terms; (b) topic complexity affected users' interaction with the thesaurus in that complex topics required more query expansion and search term selection; (c) users' prior topic‐search experience appeared to have a significant effect on their selection and evaluation of thesaurus terms; (d) in 50% of the searches where additional terms were suggested from the thesaurus, users stated that they had not been aware of the terms at the beginning of the search; this observation was particularly noticeable in the case of postgraduate students.
Categorization‐driven cross‐language retrieval of medical information
Authors: Freitas‐Junior Hermes R. , Ribeiro‐Neto Berthier , Vale Rodrigo F. , Laender Alberto H. F. , Lima Luciano R. S. 
Published: January 2006

AbstractThe Web has become a large repository of documents (or pages) written in many different languages. In this context, traditional information retrieval (IR) techniques cannot be used whenever the user query and the documents being retrieved are in different languages. To address this problem, new cross‐language information retrieval (CLIR) techniques have been proposed. In this work, we describe a method for cross‐language retrieval of medical information. This method combines query terms and related medical concepts obtained automatically through a categorization procedure. The medical concepts are used to create a linguistic abstraction that allows retrieval of information in a language‐independent way, minimizing linguistic problems such as polysemy. To evaluate our method, we carried out experiments using the OHSUMED test collection, whose documents are written in English, with queries expressed in Portuguese, Spanish, and French. The results indicate that our cross‐language retrieval method is as effective as a standard vector space model algorithm operating on queries and documents in the same language. Further, our results are better than previous results in the literature.
Stabilization of unusual structures in peptides using α,β‐dehydrophenylalanine: Crystal and solution structures of Boc–Pro–ΔPhe–Val–ΔPhe–Ala–OMe and Boc–Pro–ΔPhe–Gly–ΔPhe–Ala–OMe
Authors: Mathur Puniti , Ramagopal U. A. , Ramakumar S. , Jagannathan N. R. , Chauhan V. S. 
Published: January 2006

AbstractThe structures of two dehydropentapeptides, Boc–Pro–ΔPhe–Val–ΔPhe–Ala–OMe (I) and Boc–Pro–ΔPhe–Gly–ΔPhe–Ala–OMe (II) (Boc: t‐butoxycarbonyl), have been determined by nuclear magnetic resonance (NMR), circular dichroism (CD), and X‐ray crystallographic studies. The peptide I assumes a S‐shaped flat β‐bend structure, characterized by two partially overlapping type II β‐bends and absence of a second 1 ← 4 (N4H · · · O1′) intramolecular hydrogen bond. This is in contrast to the generally observed 310‐helical conformation in peptides with ΔPhe at alternate positions. This report describes the novel conformation assumed by peptide I and compares it with that of the conserved tip of the V3 loop of the HIV‐1 envelope glycoprotein gp120 (sequence, G:P319 to F:P324, PDB code 1ACY). The tip of the V3 loop also assumes a S‐shaped conformation with Arg:P322, making an intramolecular side‐chain–backbone interaction with the carbonyl oxygen of Gly:P319. Interestingly, in peptide I, CγHVal3 makes a similar side‐chain–backbone CH · · · O hydrogen bond with the carbonyl oxygen of the Boc group. The observed overall similarity indicates the possible use of the peptide as a viral antagonist or synthetic antigen. Peptide II adopts a unique turn followed by a 310‐helix. Both peptides I and II are classical examples of stabilization of unusual structures in oligopeptides. © 2006 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 84: 298–309, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com
Characterization of β‐turn and Asx‐turns mimicry in a model peptide: Stabilization via CH · · · O interaction
Authors: Thakur A. K. , Kishore R. 
Published: January 2006

AbstractThe chemical synthesis and single‐crystal X‐ray diffraction analysis of a model peptide, Boc–Thr–Thr–NH2 (1) comprised of proteinogenic residues bearing an amphiphilic Cβ‐stereogenic center, has been described. Interestingly, the analysis of its molecular structure revealed the existence of a distinct conformation that mimics a typical β‐turn and Asx‐turns, i.e., the two Thr residues occupy the left‐ and right‐corner positions. The main‐chain torsion angles of the N‐ and C‐terminal residues i.e., semiextended: ϕ = −68.9°, ψ = 128.6°; semifolded: ϕ = −138.1°, ψ = 2.5° conformations, respectively, in conjunction with a gauche− disposition of the obligatory C‐terminus Thr CγH3 group, characterize the occurrence of the newly described β‐turn‐ and Asx‐turns‐like topology. The preferred molecular structure is suggested to be stabilized by an effective nonconventional main‐chain to side‐chain CiO · · · HC‐type intraturn hydrogen bond. Noteworthy, the observed topology of the resulting 10‐membered hydrogen‐bonded ring is essentially similar to the one perceived for a classical β‐turn and the Asx‐turns, stabilized by a conventional intraturn hydrogen bond. Considering the signs as well as magnitudes of the backbone torsion angles and the orientation of the central peptide bond, the overall mimicked topology resembles the type II β‐turn or type II Asx‐turns. An analysis of Xaa–Thr sequences in high‐resolution X‐ray elucidated protein structures revealed the novel topology prevalence in functional proteins (unpublished). In view of indubitable structural as well as functional importance of nonconventional interactions in bioorganic and biomacromolecules, we intend to highlight the participation of Thr CγH in the creation of a short‐range CO · · · HCγ‐type interaction in peptides and proteins. © 2006 Wiley Periodicals, Inc. Biopolymers 81: 440–449, 2006This article was originally published online as an accepted preprint. The “Published Online” date corresponds to the preprint version. You can request a copy of the preprint by emailing the Biopolymers editorial office at biopolymers@wiley.com