bluuebunny/crossref_metadata_2025_split huggingface dataset:
The floating population's household strategies and the role of migration in China's regional development and integration
Authors: Zhu Yu 
Published: December 2003

AbstractThis paper examines the floating population, one of the most important products of China's reform and open‐door policies since the 1980s, from the perspectives of household strategies in migration, regional development and regional integration. Based on various data sources, including government statistics, questionnaire surveys, literature research and case studies, the paper suggests that the emergence and development of the floating population has been one response to widening regional gaps, one of the major issues arising from China's recent development. One cause of this common, non‐permanent form of migration is China's household registration system, but the household strategies of migrants must also be recognised as an important element underpinning this process. Further analysis shows that the attraction of the prosperous areas to the floating population has been closely related to the involvement of China's coastal areas in the process of globalisation. One special group of migrants and their descendants, that is the Chinese overseas and Chinese in Hong Kong, Macao and Taiwan, have played important roles in this process and have contributed greatly to the prosperity of the coastal areas. It is argued that the new generation of migrants, the floating population who have also played an important role in the prosperity of the coastal areas, may also be instrumental in the development of their hometowns, helping to reduce the problem of regional disparity in China. Thus an important implication of this study is that although migrants often move because of unbalanced regional development, eventually they could be a driving force for regional integration; this should be given more attention in both academic research and policy making. Copyright © 2003 John Wiley & Sons, Ltd.
The effect of phosphorylcholine‐coated materials on the inflammatory response and fibrous capsule formation: In vitro and in vivo observations
Authors: Goreish Hind H. , Lewis Andrew L. , Rose Susanna , Lloyd Andrew W. 
Published: December 2003

AbstractSeveral experiments were performed to compare the in vitro adhesion of human macrophage and granulocyte inflammatory cells to polyethylene terephthalate substrate and the same coated with a phosphorylcholine (PC)‐based polymer. The inclusion of various types of serum at different stages in the assay indicated that protein adsorption and passivation of the surface may be responsible for reducing the number of inflammatory cells adhering to the uncoated polyethylene terephthalate controls. In all of the assays performed there was a statistically significant reduction (p < 0.05; analysis of variance) of the number of inflammatory cells adhering to the PC‐coated samples, linked to the ability of these surfaces to resist protein adhesion. Implantations of PC‐coated stainless steel and high‐density polyethylene USP control samples were made in a rabbit intramuscular model. Histological examination of the number of inflammatory cells present around the implant sites 4 weeks postimplantation showed there were 40% less cells associated with the PC‐coated samples compared with control, but this was not statistically significant. Fibrous capsule thickness, however, whereas marginally less at 4 weeks, had almost completely regressed for the PC‐coated sample at 13 weeks postimplantation and was statistically thinner (p < 0.01; Mann‐Whitney U test) than the high‐density polyethylene USP control. These findings support the view that low biointeractions observed for PC‐based technology in vitro can result in reduced inflammation and foreign body reaction in vivo. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 1–9, 2004
Disulfide‐crosslinked hyaluronan–gelatin sponge: Growth of fibrous tissue in vivo
Authors: Liu Yanchun , Shu Xiao Zheng , Gray Steven D. , Prestwich Glenn D. 
Published: December 2003

AbstractThe modification of hyaluronan (HA) and gelatin using dithiobis(propanoic dihydrazide) (DTP) has provided two thiolated macromolecular components of the extracellular matrix (ECM), specifically HA–DTPH and gelatin–DTPH. Blends of these thiolated ECM components were crosslinked in air to form hydrogels that were interpenetrating disulfide‐crosslinked networks. Lyophilization of the hydrogels afforded sponge‐like macroporous scaffolds suitable for cell attachment and proliferation. Increasing percentages of gelatin–DTPH (0, 25, 50, and 75%) were blended with HA–DTPH, and the resulting sponges were evaluated in vitro and in vivo as scaffolds for tissue engineering by seeding with human tracheal scar (HTS) fibroblasts. While cells failed to attach and grow in HA‐only sponges, the gelatin‐modified HA sponges promoted cell adhesion, proliferation, and spreading in vitro. Optimal attachment and growth was observed with 50% gelatin–HA sponges. Cell attachment to the gelatin–HA sponge could be blocked by preincubation of cells with a soluble fibronectin peptide Gly‐Arg‐Gly‐Asp (GRGD). Finally, HTS fibroblast‐seeded gelatin–HA sponges were implanted into the flanks of nude mice and evaluated at 2 and 8 weeks postimplantation. The sponges were fully biocompatible and new fibrous tissue formed, gradually replacing the sponge‐like scaffold. The gelatin–HA sponges act as synthetic, macroporous, covalent mimics of the ECM and constitute novel scaffolds for cell growth and tissue augmentation. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 142–149, 2004
Attachment of hyaluronan to metallic surfaces
Authors: Pitt William G. , Morris Robert N. , Mason Mitchell L. , Hall Matthew W. , Luo Yi , Prestwich Glenn D. 
Published: December 2003

AbstractMetal implants are in general not compatible with the tissues of the human body, and in particular, blood exhibits a severe hemostatic response. Herein we present results of a technique to mask the surface of metals with a natural biopolymer, hyaluronan (HA). HA has minimal adverse interactions with blood and other tissues, but attachment of bioactive peptides can promote specific biological interactions. In this study, stainless steel was cleaned and then surface‐modified by covalent attachment of an epoxy silane. The epoxy was subsequently converted to an aldehyde functional group and reacted with hyaluronan through an adipic dihydrazide linkage, thus covalently immobilizing the HA onto the steel surface. Fluorescent labeling of the HA showed that the surface had a fairly uniform covering of HA. When human platelet rich plasma was placed on the HA‐coated surface, there was no observable adhesion of platelets. HA derivatized with a peptide containing the RGD peptide sequence was also bound to the stainless steel. The RGD‐containing peptide was bioactive as exemplified by the attachment and spreading of platelets on this surface. Furthermore, when the RGD peptide was replaced with the nonsense RDG sequence, minimal adhesion of platelets was observed. This type of controlled biological activity on a metal surface has potential for modulating cell growth and cellular interactions with metallic implants, such as vascular stents, orthopedic implants, heart valve cages, and more. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 95–106, 2004
Matrix metalloproteinases MMP‐2, ‐9 and tissue inhibitors TIMP‐1, ‐2 expression and secretion by primary human osteoblast cells in response to titanium, zirconia, and alumina ceramics
Authors: Oum'hamed Z. , Garnotel R. , Josset Y. , Trenteseaux C. , Laurent‐Maquin D. 
Published: December 2003

AbstractOsteogenic properties of bone cells are a key parameter governing osseointegration of implant devices. In this context, osteoblasts have a central role via extracellular matrix synthesis and remodeling that they regulate through different protease activity. In this study, we have analyzed the expression of two matrix metalloproteinases (MMPs): MMP‐2 (72 kDa) and MMP‐9 (92 kDa) and their specific tissue inhibitors TIMP‐1 and TIMP‐2 in primary human osteoblastic cells. The effect of titanium, zirconia, and alumina ceramics on the synthesis of these proteases was assessed using reverse transcriptase‐polymerase chain reaction, enzyme‐linked immunosorbent assay, and zymographic analysis. Our results showed that osteoblasts express MMP‐2 and ‐9 mRNA. Furthermore, MMP‐2 mRNA expression was decreased by titanium and increased by alumina whereas zirconia did not have any significant effect. Conversely, MMP‐9 mRNA expression was stimulated by titanium but decreased with zirconia, whereas alumina induced no significant changes. Zymographic analysis has evidenced pro‐MMP‐2 gelatinolytic activity in all cell populations with time‐dependent increase profile; pro‐MMP‐9, however, was not detected. Enzyme‐linked immunosorbent assay data confirmed the production of MMP‐2 and very low levels of MMP‐9. In addition, TIMP‐1 was secreted in 24‐h‐cultured cells and increased to maximal level at 48–72 h whereas TIMP‐2 levels were very low. The interactions between human osteoblasts and the studied biomaterials altered both MMP‐2, ‐9 and TIMP‐1expression indicating that biomaterials may influence osseointegration and bone remodeling. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 114–122, 2004
Peripheral blood cell separation through surface‐modified polyurethane membranes
Authors: Higuchi Akon , Yamamiya Shin‐ichi , Yoon Boo Ok , Sakurai Masaru , Hara Mariko 
Published: December 2003

AbstractCell separation from peripheral blood was investigated using surface‐modified polyurethane (PU) membranes with different functional groups. Both red blood cells and platelets could pass through unmodified PU and PU‐SO3H membranes, whereas the red blood cells preferentially passed through PU‐N(C2H5)2 and PU‐NHC2H4OH membranes. The permeation ratio of T and B cells was <25% for the surface‐modified and unmodified PU membranes. CD34+ cells have been recognized as various kinds of stem cells including hematopoietic and mesenchymal stem cells. The adhesiveness of CD34+ cells on the PU membranes was found to be higher than that of red blood cells, platelets, T cells, or B cells. Overall, the adhesiveness of blood cells on the PU membranes increased in the following order: red blood cells ≤ platelets < T cells ≤ B cells < CD34+ cells. Treatment of PU‐COOH membranes with a human albumin solution to detach adhered blood cells, allowed recovery of mainly CD34+ cells in the permeate, whereas both red blood cells and platelets could be isolated in the permeate using unmodified PU membranes. The PU membranes showed different permeation and recovery ratios of specific cells depending on the functional groups attached to the membranes. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 34–42, 2004
Microstructural disassembly of calcium phosphates
Authors: Wang Haibo , Lee Jong‐Kook , Moursi Amr M. , Anderson David , Winnard Phillip , Powell Heather , Lannutti John 
Published: December 2003

AbstractMicrostructural factors may play a role in the osseointegration of calcium phosphates. In this paper, direct microstructural interactions between crystalline calcium phosphates and the biological milieu are reported. Degradation via exposure to osteoblast culture closely resembles in vivo interactions with subcutaneous tissues in a bovine model at early time periods. That these interactions were common to both experiments constitutes one of the few known examples of in vitro–in vivo correspondence. Interestingly, the degradation of phase pure hydroxyapatite (HA) in vitro was more rapid than that of biphasic HA in vivo. In both cases, grain extraction/pullout was frequently observed. This suggests a connection to smaller‐scale observations of epitaxial CHA nucleation and growth on pre‐existing HA grains. A microstructure in which the grain boundary is dissolving/corroding can apparently be disassembled by forces transmitted through biological structures. These observations are distinct from those of simple non‐biological solutions and prove that biological environments can interact with the material beneath the ceramic‐cell/ceramic‐tissue interface. Many often ignored microstructural factors—grain size, shape, grain boundary strength and the presence of impurity phases—may in fact control degradation. We also suggest that even relatively modest initial grain sizes will, in combination with the mild/absent foreign body response to calcium phosphates, result in lengthy in vivo particle resistence. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 61–70, 2004
Numerical failure analysis of glass‐fiber‐reinforced composites
Authors: Tanimoto Yasuhiro , Nishiwaki Tsuyoshi , Nemoto Kimiya 
Published: December 2003

AbstractThe purpose of this work was to propose a new numerical model for glass‐fiber‐reinforced composites. The proposed numerical model was constructed with orthotropic shell, isotropic shell, and beam elements representing glass fiber cloth, silica filler, and the remaining matrix resin, respectively. The proposed model was applied to failure analysis under three‐point bending conditions. The validity of the numerical model was checked through comparisons with experimental results. Four types of specimens were used: composite resin, and composite resin with neutral, upper, and lower glass‐fiber cloth reinforcement insertions. For all types, close agreement between the analytical and experimental results was confirmed. This indicates that the proposed numerical model is effective for evaluating the mechanical behaviors of glass‐fiber‐reinforced composites. © 2003 Wiley Periodicals, Inc. J Biomed Mater Res 68A: 107–113, 2004
Is re‐feeding efficiency compromised by prolonged starvation during aestivation in the green striped burrowing frog, Cyclorana alboguttata?
Authors: Cramp Rebecca L. , Franklin Craig E. 
Published: December 2003

AbstractWe examined several morphological parameters of the gastrointestinal tract, digesta passage rates, and nutrient assimilation efficiencies of Green‐striped Burrowing frogs (Cyclorana alboguttata) following prolonged fasting during three months of aestivation and compared these with frogs that had been continuously fed. Whole animal digesta passage rates were significantly reduced following three months aestivation as a result of a decreased digesta evacuation rate from the stomach. Furthermore, food was selectively retained in the small intestine for an increased time following three months of aestivation. Overall digestibility of food and nitrogen, carbon, and energy extraction efficiencies were not significantly different from control values following three months of aestivation. These findings suggest that C. alboguttata employs reduced digesta passage rates so as to maximize nutrient assimilation efficiency following prolonged food deprivation during aestivation. J. Exp. Zool. 300A:126–132, 2003. © 2003 Wiley‐Liss, Inc.
Ultrastructural localization of spicule matrix proteins in normal and metalloproteinase inhibitor‐treated sea urchin primary mesenchyme cells
Authors: Ingersoll Eric P. , Mcdonald Kent L. , Wilt Fred H. 
Published: December 2003

AbstractStudies of the sea urchin larval skeleton have contributed greatly to our understanding of the process of biomineralization. In this study we have undertaken an investigation of the morphology of skeleton formation and the localization of proteins involved in the process of spicule formation at the electron microscope level. Sea urchin primary mesenchyme cells undergo a number of morphological changes as they synthesize the larval skeleton. They form a large spicule compartment that surrounds the growing spicule and, as spicule formation comes to an end, the density of the cytoplasm decreases. Inhibition of spicule formation by specific matrix metalloproteinase inhibitors or serum deprivation has some subtle effects on the morphology of cells and causes the accumulation of specific classes of vesicles. We have localized proteins of the organic matrix of the spicule and found that one protein, SM30, is localized to the Golgi apparatus and transport vesicles in the cytoplasm as well as throughout the occluded protein matrix of the spicule itself. This localization suggests that SM30 is an important structural protein in the spicule. Another spicule matrix protein, SM50, has a similar cytoplasmic localization, but in the spicule much of it is localized at the periphery of the spicule compartment, and consequently it may play a role in the assembly of new material onto the growing spicule or in the maintenance of the integrity of the matrix surrounding the spicule. J. Exp. Zool. 300A:101–112, 2003. © 2003 Wiley‐Liss, Inc.
Muscle enzyme activities in a deep‐sea squaloid shark, Centroscyllium fabricii, compared with its shallow‐living relative, Squalus acanthias
Authors: Treberg Jason R. , Martin R. Aidan , Driedzic William R. 
Published: December 2003

AbstractThe activities of several enzymes of energy metabolism were measured in the heart, red muscle, and white muscle of a deep and a shallow living squaloid shark, Centroscyllium fabricii and Squalus acanthias, respectively. The phylogenetic closeness of these species, combined with their active predatory nature, similar body form, and size makes them well matched for comparison. This is the first time such a comparison has been made involving a deep‐sea elasmobranch. Enzyme activities were similar in the heart, but generally lower in the red muscle of C. fabricii. Paralleling the trend seen in deep‐sea teleosts, the white muscle of C. fabricii had substantially lower activities of key glycolytic enzymes, pyruvate kinase and lactate dehydrogenase, relative to S. acanthias or other shallow living elasmobranchs. Unexpectedly, between the squaloid sharks examined, creatine phosphokinase activity was higher in all tissues of the deep living C. fabricii. Low white muscle glycolytic enzyme activities in the deep‐sea species coupled with high creatine phosphokinase activity suggests that the capacity for short burst swimming is likely limited once creatine phosphate supplies have been exhausted. J. Exp. Zool. 300A:133–139, 2003. © 2003 Wiley‐Liss, Inc.
Estimate and production of milk energy in two subspecies of red deer: Cervus elaphus hispanicus and C. e. scoticus
Authors: Landete‐Castillejos Tomás , Molina Pilar , Garcia Andrés , Gomez Jose Angel , Gallego Laureano 
Published: December 2003

AbstractThis study estimates the caloric value of red deer milk as assessed relating bomb calorimetry data with the main milk nutrients. The study also examines milk energy estimates and lactation variables to compare Iberian red deer hinds (Cervus elaphus hispanicus) and the most studied Scottish red deer (C. e. scoticus). The final model predicted energy value (Ecal) in kcal/g of fresh milk from fat (F) and protein (P) content of milk, but not lactose: Ecal = 0.345 + 8.332 F + 5.403 P. Energy content per gram of milk increased with lactation stage but there was no difference between subspecies. However, subspecies differed in the daily and total energy production. Although milk energy values appeared to differ with estimates following the most used model developed from livestock, milk energy of deer estimated by both methods showed a very high correlation with each other, and both yielded also similar correlation coefficients with the remaining lactation variables. Calf gains showed a greater correlation with mean protein content and total protein yield, than with total energy yield or other milk nutrients. Milk protein appears to be more relevant to calf growth than gross energy yield. J. Exp. Zool. 300A:152–157, 2003 © 2003 Wiley‐Liss, Inc.
How many disjoint 2‐edge paths must a cubic graph have?
Authors: Kelmans Alexander , Mubayi Dhruv 
Published: December 2003

AbstractIn this paper we show that every simple cubic graph on n vertices has a set of at least ⌈ n/4 ⌉ disjoint 2‐edge paths and that this bound is sharp. Our proof provides a polynomial time algorithm for finding such a set in a simple cubic graph. © 2003 Wiley Periodicals, Inc. J Graph Theory 45: 57–79, 2003
Detoxification of 4‐hydroxynonenal (HNE) in keratinocytes: characterization of conjugated metabolites by liquid chromatography/electrospray ionization tandem mass spectrometry
Authors: Aldini Giancarlo , Granata Paola , Orioli Marica , Santaniello Enzo , Carini Marina 
Published: December 2003

AbstractKeratinocytes are potential targets of lipid peroxidation products (α,β‐unsaturated aldehydes) generated in the skin following UV exposure, among which the most abundant and toxic product is 4‐hydroxy‐trans‐2,3‐nonenal (HNE). The aim of this study was to investigate the ability of keratinocytes (NCTC2544 cell lines) to detoxify HNE, through characterization of metabolites, until now never demonstrated, using a combined analytical approach (liquid chromatography (LC) and liquid chromatography/mass spectrometry (LC/MS)). Incubation of cells with HNE (up to 200 µM) was performed in order to evaluate the ability of the cells to detoxify this toxic aldehyde, and indicated that the cell viability was maintained under these conditions. LC analysis of the extracellular media from keratinocytes incubated with 100 µM HNE shows a time‐dependent decrease of HNE, disappearance from the medium within 2 h and concomitant formation of two unconjugated (phase I) metabolites, 4‐hydroxy‐2‐nonenoic acid (HNA) and 1,4‐dihydroxy‐2‐nonene (DHN), which were both identified and quantified by LC and accounted for 48.8 ± 4.6% of the HNE dose. Four additional metabolites were identified in the extracellular medium by reversed‐phase LC coupled with electrospray ionization tandem mass spectrometry (LC/ESI‐MS/MS) with positive and negative ion detection as Michael adducts (phase II metabolites), arising by the addition of the nucleophilic sulfur of glutathione (GSH) to the electrophilic C‐3 of HNE, followed by oxidation–reduction enzymatic processes. The GSH–HNE conjugates were (a) S‐(4‐hydroxynonanal‐3‐yl)glutathione, (b) S‐(1,4‐dihydroxy‐nonane‐3‐yl)glutathione, (c) S‐(4‐oxononanal‐3‐yl)glutathione and (d) S‐(4‐oxo‐nonan‐1‐ol‐3‐yl)glutathione, and accounted for 52.3 ± 5.8% of the HNE dose (35 nmol mg−1 protein), as estimated indirectly by measuring the extent of cellular GSH consumption (18.7 ± 1.8 nmol mg−1 protein). The time course of HNE biotransformation was then determined by monitoring the formation of metabolites inside and outside the cell at different times after HNE addition (5–120 min). A time‐dependent and almost linear formation inside the cell was observed for all the metabolites (plateau after 15 min of incubation), followed by a rapid decay and a concomitant increase in the extracellular medium (plateau of formation after 60 min). This confirms that HNE diffuses into the cell where is totally metabolized through phase I and phase II reactions to unreactive products, which are then exported outside the cell. This is the first demonstration that skin epidermal cells are able to detoxify the cytotoxic products of lipid peroxidation. Copyright © 2003 John Wiley & Sons, Ltd.