bluuebunny/crossref_metadata_2025_split huggingface dataset:
Regioselective Acylation of Ginsenosides by Novozyme 435 to Generate Molecular Diversity
Authors: Teng Rongwei , Ang Chingseng , McManus David , Armstrong David , Mau Shaiolim , Bacic Antony 
Published: July 2004

AbstractGinsenosides are major bioactive constituents of ginseng (Panax spp.; Araliaceae), a traditional Chinese medicinal herb. In order to increase the molecular diversity and broaden the potential usage of ginsenosides, ginsenosides Rd (1), Rg3 (2), (20R)‐Rg3 (3), Rh2 (4), Re (5), Rh1 (8), Rg2 (9), gypenoside XVII (6), and pseudoginsenoside F11 (7) were regioselectively acylated with vinyl acetate, catalyzed by Novozyme 435 (lipase B from Candida antarctica), in organic solvents to afford different mono‐acetyl ginsenosides. Ginsenoside Rd (1) was also acylated with vinyl decanoate or vinyl cinnamate to generate 1b and 1c, respectively. Acylation of glucosylated ginsenosides (1–4, 6, 8) occurred at the primary 6‐OH function of the terminal glucose (Glc) moiety of the sugar at C(3) or C(20) of the dammarane‐type aglycone. In contrast, ginsenosides 5, 7, and 9, containing mixed sugar moieties, resulted in acylation of both the rhamnose (Rha) and the glucose (Glc) moieties. In the case of ginsenoside Re (5) and pseudoginsenoside F11 (7), acylation at the secondary 4‐OH function of the terminal Rha moiety, attached at C(3) of the aglycone, is preferred. The structures of all acylated products were determined by extensive MALDI‐TOF‐MS and NMR analyses.
Molecular‐Sieve Honeycomb for Air Separation from Picea abies
Authors: Onyestyák György , Rees Lovat V. C. , László Krisztina 
Published: July 2004

AbstractThe cellular structure of Norway spruce (Picea abies) was transformed via a simple, single‐step carbonization process into a carbon monolith with molecular‐sieve properties. The monolith exhibited a genuine honeycomb structure derived from the original intrinsic H2O channels of the wood. The micropores formed during carbonization from the walls of the channels were shown to have a high adsorption capacity. The honeycomb monolith was tested for air separation. Micropore diffusion of N2 and O2 was found by the frequency‐response (FR) technique to be the rate‐controlling process of mass transport.
Crystal Structure of Melaminium Orthophosphate from High‐Resolution Synchrotron Powder‐Diffraction Data
Authors: De Ridder Dirk J. A. , Goubitz Kees , Brodski Vladimir , Peschar René , Schenk Henk 
Published: July 2004

AbstractThe crystal structure of melaminium orthophosphate (MP) has been determined from high‐resolution synchrotron powder‐diffraction data. The crystal packing consists of melaminium layers and pairs of orthophosphate chains connected by H‐bonds almost perpendicular to the layers. The distance between melaminium layers is 3.62 Å. Neighboring melaminium molecules do not lie in the same plane, but in two parallel planes at close distance (0.79 Å), and are shifted with respect to each other. The orthophosphate chains are connected by both intra‐chain and inter‐chain H‐bonds. The melamine is singly protonated at an endocyclic N‐atom. The powder‐diffraction data were corroborated by solid‐state NMR experiments.
Vibratilicin: a Novel Compound from the Basidiomycete Cortinarius vibratilis
Authors: Wang Fei , Tan Jian‐Wen , Liu Ji‐Kai 
Published: July 2004

AbstractA novel N‐containing compound, vibratilicin (=3‐[3‐(dimethylamino)‐4‐(hydroxyamino)‐4‐oxobutoxy]‐2‐(palmitoyloxy)propyl (9E,12E)‐octadeca‐9,12‐dienoate; 1), was isolated from the fruiting bodies of the basidiomycete Cortinarius vibratilis Fr. Compound 1 is a representative of the rare natural products containing hydroxamic acid moieties, and can be viewed as a derivative of neoengleromycin (2). Also isolated from the same fungus were five known compounds: ergosta‐5,7,22‐trien‐3β‐ol, 5α,8α‐epidioxyergosta‐6,22‐dien‐3β‐ol, p‐anisic acid, N‐(2‐hydroxyhexadecanoyl)‐4‐sphingenine, and (4E,8E)‐2‐N‐(2′‐hydroxypalmitoyl)‐1‐O‐(β‐D‐glucopyranosyl)‐9‐methyl‐4,8‐sphingadienine. Their structures were determined mainly spectroscopically, including 2D‐NMR techniques (HMBC, HMQC, 1H,1H‐COSY).
Alumina hip joints characterized by run‐in wear and steady‐state wear to 14 million cycles in hip‐simulator model
Authors: Oonishi Hironobu , Clarke Ian C. , Good Victoria , Amino Hirokazu , Ueno Masuru 
Published: July 2004

AbstractThe biphasic wear performance (run‐in; steady‐state phase) of 28‐mm alumina‐alumina hip implants was studied by hip simulator methods using bovine serum as the lubricant. The Biolox™ implants were run to 5.7 million cycles and Bioceram™ implants to 14.4 million cycles (Mc). Wear with all‐alumina total hip replacements (THR) first showed a high wear rate of the order 1.2 mm3/Mc, lasting approximately 0.17 Mc. Overall to 0.7 Mc, the run‐in phase appeared curvilinear but could be described by a linear phase averaging 0.3 mm3/Mc. From 0.7 to 1 Mc duration, the wear trend transitioned into a steady‐state phase. Wear rates from 1 to 14 Mc were of the order 0.02 mm3/Mc. Surface contamination from the serum lubricant resulted in cyclic weight fluctuations of the order 0.2 mg. The transition from average run‐in to steady‐state phase represented a wear reduction of 13‐fold. Comparing the steady‐state wear value to that in standard 28‐mm UHMWPE CUPS approaching 75 mm3/year, there was clearly a three‐orders‐of‐magnitude wear superiority in favor of ceramic cups. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 523–532, 2004
Effects of adsorbed proteins and surface chemistry on foreign body giant cell formation, tumor necrosis factor alpha release and procoagulant activity of monocytes
Authors: Shen Mingchao , Garcia Iris , Maier Ronald V. , Horbett Thomas A. 
Published: July 2004

AbstractThe adhesion and activation of monocytes and macrophages are thought to affect the foreign body response to implanted medical devices. However, these cells interact with devices indirectly, because of the prior adsorption of proteins. Therefore, we preadsorbed several “model” biomaterial surfaces with proteins and then measured foreign body giant cell (FBGC) formation, tumor necrosis factor alpha (TNFα) release, and procoagulant activity. The model surfaces were tissue culture polystyrene (TCPS), untreated polystyrene (PS), and Primaria, whereas the proteins used were albumin, fibronectin, fibrinogen, and immunoglobulin. FBGC formation, TNFα release, and procoagulant activity of monocytes were the highest for surfaces preadsorbed with IgG. FBGC formation was lower on surfaces with adsorbed fibrinogen and fibronectin than on uncoated surfaces. TNFα release and procoagulant activity of monocytes were similar on surface adsorbed with fibrinogen, fibronectin, or albumin. Monocyte activation was also affected by the surface chemistry of the substrates, because FBGC formation was the highest on PS and the lowest on TCPS. Monocyte procoagulant activity was the highest on Primaria. Adsorbed proteins and surface chemistry were found to have strong effects on FBGC formation, monocyte TNFα release, and procoagulant activityin vitro, providing support for the idea that these same variables could affect macrophage‐mediated foreign body response to biomaterialsin vivo. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 533–541, 2004
Three‐month, zero‐order piroxicam release from monodispersed double‐walled microspheres of controlled shell thickness
Authors: Berkland Cory , Cox Amanda , Kim Kyekyoon (Kevin) , Pack Daniel W. 
Published: July 2004

AbstractDouble‐walled microspheres represent an increasingly important class of drug delivery devices that provide enhanced control of drug delivery schedules. Clearly, the overall particle size and shell thickness are important parameters in modulating the drug release rates. Precision particle fabrication technology has been used to fabricate double‐walled microspheres of predefined uniform diameters of 40–60 μm exhibiting a poly(D,L‐lactide‐co‐glycolide) (PLG) core and poly(L‐lactide) (PL) shell of controllable thickness from ∼2 to 10 μm. The release of a model small‐molecule drug, piroxicam, from uniform microspheres of pure PLG and PL is compared to the release from double‐walled microspheres exhibiting different PL shell thicknesses. The presence of the PL shell enveloping a PLG core essentially eliminated the initial “burst” of piroxicam that was observed when the drug was released from pure PLG microspheres. In addition, increasing the PL shell thickness shifted the release profile from a biphasic shape for pure PLG microspheres to zero‐order piroxicam release over 3 months for the thickest (∼10 μm) PL shell. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 576–584, 2004
In vitro response of osteoblast‐like and odontoblast‐like cells to unsubstituted and substituted apatites
Authors: Inoue Miho , LeGeros Racquel Z. , Inoue Masahisa , Tsujigiwa Hidetsugu , Nagatsuka Hitoshi , Yamamoto Toshio , Nagai Noriyuki 
Published: July 2004

AbstractDifferent types of calcium phosphate compounds [calcium‐deficient apatite (CDA); beta‐tricalcium phosphate (β‐TCP); biphasic calcium phosphate (BCP)] are commercially available for medical and dental applications as bone substitute materials. Most of the reported in vitro studies on cell‐material interactions have used osteoblast‐like cells. The purpose of this study was to investigate the in vitro response of osteoblast‐like (MC3T3‐E1) and odontoblast‐like (MDPC23) cells on unsubstituted (HA) and substituted (F‐substituted) apatites. MC3T3‐E1 and MDPC23 were cultured in alpha‐modified medium containing 10% fetal bovine serum, ascorbic acid (50 μg/mL) and β‐glycerophosphate (2 mM). The cells were seeded on pellets made from HA, and FAp (with low, medium, and high F concentrations). Cell morphology was observed after 7 and 14 days using scanning electron microscopy (SEM). Cell attachment and differentiation were determined from the DNA content, alkaline phosphatase (ALP) activity, and total collagen content. Pellet surface composition was characterized by using Fourier Transform infrared spectroscopy. MC3T3‐E1 and MDPC23 cells on HA were normal in shape and in fusion but not on FAp. Results of this study showed that the pattern of cell proliferation of osteoblast‐like cells was different from that of the odontoblast‐like cells. This study suggests that cell morphology, fusion, and proliferation on biomaterial surfaces depend on cell type (osteoblast‐like vs odontoblast‐like cell) and biomaterial composition (unsubstituted vs substituted F‐apatites). © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 585–593, 2004
Restoration of function after spinal cord transection using a collagen bridge
Authors: Yoshii Satoru , Oka Masanori , Shima Mitsuhiro , Taniguchi Ataru , Taki Yoshiro , Akagi Masao 
Published: July 2004

AbstractThe restoration of function of transected adult mammalian spinal cord without living tissue has not been reported previously. We report the first success of functional restoration of transected spinal cord without living tissue. We grafted collagen filaments parallel or transverse to the axis of the spinal cord to bridge 5‐mm defects of 47 adult rat spinal cords. Twenty‐five rats were used as a control. Of the 72 rats, 42 rats survived the experimental period. At 4 weeks postoperatively, regenerated axons crossed the proximal and distal spinal cord‐implant interfaces in all 5 rats of the parallel‐grafted group. At 12 weeks postoperatively, the rats in the parallel‐grafted group (8 rats) could walk, run, and climb with hind‐forelimb coordination. The somatosensory‐evoked potentials were seen. Results suggest that the collagen filaments support the axonal regeneration of the transected spinal cord and the restoration of function when grafted parallel to the axis of the spinal cord. The functional restoration appeared to be permanent, raising the possibility of therapeutic application in humans. © 2004 Wiley Periodicals, Inc. J Biomed Mater Res 70A: 569–575, 2004
Cover Picture: Macromol. Rapid Commun. 15/2004
Authors: Hiroi Ryoichi , Ray Suprakas Sinha , Okamoto Masami , Shiroi Takashi 
Published: July 2004

Cover: The structure of pristine protonated layered titanate (HTO) (left) and the bright‐field transmission electron microscopy image of a photodegradable nanocomposite (right) prepared by melt extrusion of polylactide and organically modified HTO are shown on the cover.Further details can be found in the Communication by R. Hiroi, S. S. Ray, M. Okamoto,* and T. Shiroi on page 1359.
Association of a mutation in the ryanodine receptor 1 gene with equine malignant hyperthermia
Authors: Aleman Monica , Riehl Joyce , Aldridge Brian M. , Lecouteur Richard A. , Stott Jeffrey L. , Pessah Isaac N. 
Published: July 2004

AbstractEquine malignant hyperthermia (MH) has been suspected but never genetically confirmed. In this study, we investigated whether mutations in a candidate gene,RyR1, were associated with MH in two clinically affected horses.RyR1gene sequences revealed polymorphisms in exons 15, 17, and 46 inWTRyR1 andMHRyR1 horses with one derived amino acid change inMHRyR1 exon 46, R2454G. TheMHRyR1 horses were genetically heterozygous for this mutation, but presented an MH phenotype with halothane challenge. Skeletal sarcoplasmic reticulum from a R2454G heterozygote collected during a fulminant MH episode showed significantly higher affinity and density of [3H]ryanodine‐binding sites compared toWTRyR1, but no differences in Ca2+, Mg2+, and caffeine modulation. In conclusion, an autosomal missense mutation inRyR1is associated with MH in the horse, providing a screening test for susceptible individuals. [3H]ryanodine‐binding analysis suggests that long‐lasting changes in RyR1 conformation persists in vitro after the triggering event. Muscle Nerve 30: 356–365, 2004
Cardinality constrained path covering problems in grid graphs
Authors: Apollonio N. , Caccetta L. , Simeone B. 
Published: July 2004

AbstractIn this article we continue our study on the complexity of Path Covering Problems started in 2. Here, taking one further step, we investigate the complexity of the problem on grids. For special classes of grids (general grids, grids with a fixed number of rows, ladders), and several special unweighted path collections (general paths, paths of length 2, L‐shaped paths, pipes, hooks, staples) we either give polynomial‐time algorithms or prove NP‐completeness results. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(2), 120–131 2004
A competitive scheduling problem and its relevance to UMTS channel assignment
Authors: Arbib Claudio , Smriglio Stefano , Servilio Mara 
Published: July 2004

AbstractThis article investigates a two‐user competitive scheduling problem. The problem arises in a Universal Mobile Telecommunication System (UMTS) developed within the European IST project FUTURE: given two mobile terminals, one wants to maximize the on‐time data packets transmitted to one user, while guaranteeing a certain amount of on‐time data packets to the other. We show that the problem is NP‐hard, despite peculiar properties of data and solutions. We propose a fast lagrangian heuristic able to cope with a severe real‐time requirement, and compare it to a greedy‐like heuristic on a set of practical instances. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(2), 132–141 2004
Decomposition techniques for the minimum toll revenue problem
Authors: Bai Lihui , Hearn Donald W. , Lawphongpanich Siriphong 
Published: July 2004

AbstractThe objective of the minimum toll revenue (MINREV) problem is to find tolls that simultaneously cause users to use the transportation network efficiently and minimize the total toll revenues that must be collected. This article investigates the Dantzig‐Wolfe (DW) decomposition as an approach for solving the MINREV problem and establishes its relationships with a cutting plane algorithm and other proposed approaches. The article also identifies the variant of DW decomposition most suitable for implementation. Numerical experiments with real transportation networks suggest that DW decomposition is robust and should be used when the problems are too large for standard linear programming software. Although transportation planning is the application emphasized in this article, it should be noted that the MINREV problem also has applications in telecommunication network design and control. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(2), 142–150 2004
An implicit enumeration scheme for the batch selection problem
Authors: Agnetis A. , Rossi F. , Smriglio S. 
Published: July 2004

AbstractAn important problem arising in the management of logistic networks is the following: given a set of activities to be performed, each requiring a set of resources, select the optimal set of resources compatible with the system capacity constraints. This problem is called Batch Selection Problem (BSP) from traditional applications to flexible manufacturing. BSP is known to be NP‐hard, and is also considered a difficult integer programming problem. In fact, polyhedral approaches to BSP suffer from the poor quality of the bound provided by the linear relaxation, even after strengthening. We devise an implicit enumeration scheme that attempts to overcome this difficulty. It is based on a formulation of BSP, which is equivalent to a stable set problem with one side constraint. This allows to exploit the upper bound, not only for pruning subproblems, but also for controlling the number and the quality of the subproblems generated. We show the effectiveness of the approach by an extensive computational experience on real‐sized randomly generated instances. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(2), 151–159 2004
A neighborhood search algorithm for the combined through and fleet assignment model with time windows
Authors: Ahuja Ravindra K. , Liu Jian , Orlin James B. , Goodstein Jon , Mukherjee Amit 
Published: July 2004

AbstractThe fleet assignment model (FAM) for an airline assigns fleet types to a set of flight legs that satisfies a variety of constraints and minimizes the cost of the assignment. The through assignment model matches inbound flight legs into a city with the outbound flight legs at the same city that are flown by the same plane types and creates through connections (that is, flight connections with one stopover). The combined through and fleet assignment model (ctFAM) integrates both the models into a single model and obtains optimal fleet and through assignments by varying both sets of decision variables simultaneously. In a recent article, Ahuja et al. (2001) proposed a very large‐scale neighborhood (VLSN) search algorithm for the ctFAM. In this article, we generalize this approach to incorporate time windows. In the model considered in this article, each flight leg has a time window associated with its departure time. The objective is to determine fleet assignment, departure time of all flight legs, and through connections between flights to minimize the total cost of fleet assignment and through connections. We call this model ctFAM with time windows or ctFAM‐TW. Allowing flexibility in the flight departure time creates greater opportunities for fleet assignment and through connections, and can reduce costs substantially. We describe the details of a VLSN search algorithm for ctFAM‐TW and also present computational results of our algorithm on the data provided by a large U.S. airline. © 2004 Wiley Periodicals, Inc. NETWORKS, Vol. 44(2), 160–171 2004
Desirable features in mold filling simulations for Liquid Composite Molding processes
Authors: Šimáček Pavel , Advani Suresh G. 
Published: July 2004

AbstractNumerical simulations of the mold filling process in various Liquid Composite Molding (LCM) techniques, in which the fiber reinforcements represent the porous media and the polymeric resin is the impregnating fluid, have been successfully utilized for over a decade now, but they continue to be under dynamic development. Some of the recent applications are the increased emphasis on design optimization, control of the impregnation process and the rapid introduction of new LCM techniques such as the Vacuum Assisted Resin Transfer Molding (VARTM). This paper describes the requirements that these new applications demand on the implementation of such numerical simulation for modeling mold filling in LCM processes, namely Resin Transfer molding (RTM) and VARTM. Liquid Injection Molding Simulation (LIMS) developed at the University of Delaware, which can simulate the flow in such processes, has been modified to encompass these features. It addresses practical issues concerning modeling the part geometry, such as the proper choice of one‐, two‐ and three‐dimensional elements and their effective combinations. It also describes the simulation of non‐trivial boundary conditions, placement of sensors and allowing for resin injection control using the functions built into the simulation program and the embedded scripting language. Several examples are presented to highlight the importance of its flexibility. The paper also addresses some VARTM specific issues, such as the modeling of distribution media, dimensional change during filling and fiber tow saturation. Polym. Compos. 25:355–367, 2004. © 2004 Society of Plastics Engineers.
Effect of reinforcing glass fibers on morphology and properties of thermoplastic modified epoxy‐aromatic diamine matrix
Authors: Bonnaud L. , Pascault J. P. , Sautereau H. , Zhao J. Q. , Jia D. M. 
Published: July 2004

AbstractA usual way to improve the fracture toughness of thermosetting polymers consists of using an initially miscible thermoplastic that phase separates at a particular conversion, depending on composition and reaction temperature. This work deals with the effect of glass reinforcing fibers on the morphologies of polyetherimide and aminografted polyetherimide toughened epoxy‐diamine systems. The presence of fibers in these systems does not affect the phase separation process, but the final morphology changes in the case where polyetherimide (PEI) is used as an additive. Furthermore, the use of aminografted PEI does not change the previously observed morphology. In terms of mechanical properties, the use of fibers leads to a great improvement in the fracture energy, indicating that good adhesion between fiber and matrix is also achieved. Polym. Compos. 25:368–374, 2004. © 2004 Society of Plastics Engineers.
Non‐isothermal flow of a polymeric liquid through rounded rectangular ducts
Authors: Wu G. H. 
Published: July 2004

AbstractThe 3D non‐isothermal creeping flow of nylon‐6 in a bent rectangular duct is studied numerically. A differential‐type non‐isothermal White‐Metzner constitutive equation is used for this flow simulation. Computational results are obtained by the elastic‐viscous split‐stress (EVSS) finite element method, incorporating the streamline‐upwind Petrov‐Galerkin (SUPG) scheme. The generated thermal field is entirely due to viscous heating. Essential flow characteristics, including temperature distribution in the flow field, are predicted. The resulting average Nusselt numbers along the walls and dimensionless bulk temperatures along the channel are obtained. Subsequently, the effects of flow‐rate and geometry are investigated. Polym. Compos. 25:375–383, 2004. © 2004 Society of Plastics Engineers.