bluuebunny/crossref_metadata_2025_split huggingface dataset:
Effects of in Vitro Glycation on Fe3+ Binding and Fe3+ Isoforms of Transferrin
Authors: Van Campenhout Ann , Van Campenhout Christel , Lagrou Albert René , Manuel-y-Keenoy Begoña 
Published: July 2004

AbstractBackground: In diabetes, protein function is altered by glycation, but the impact on the Fe3+ binding and antioxidant functions of transferrin (Tf) is largely unknown. The aim of the present study was to investigate the effects of glycation on the distribution of Fe3+ on the two Fe3+-binding sites of Tf.Methods: In vitro glycation of Tf was accomplished by preincubation with glucose for 14 days. Tf was loaded with Fe3+ compounds to achieve theoretical Tf Fe3+ saturations of 32%, 64%, and 96% (monitored by spectrophotometry). Fe3+-Tf isoforms were separated by isoelectric focusing.Results: Fe3+ binding was highest when Tf was incubated with Fe:nitrilotriacetic acid and reached a steady state overnight. Increasing the Fe3+ load led to a shift of isoform profile toward the diferric form (Fe2-Tf): in freshly prepared Tf, Fe2-Tf represented 6%, 30%, and 66% of all isoforms at 32%, 64%, and 96% theoretical Fe3+ saturation, respectively. Fe3+ was equally distributed to the monoferric Tf forms with Fe3+ bound to the amino (Fe1N-Tf) and carboxy termini (Fe1C-Tf). Glycation decreased binding of Fe3+ to Tf (monitored at 450 nm). At low theoretical Fe3+ saturation (32%), glycation increased the mean (SD) proportion of Fe2-Tf: 18 (3)% in the presence of 33.3 mmol/L glucose vs 12 (4)% with 0 mmol/L glucose (P = 0.01). In contrast, at 96% theoretical Fe3+ saturation, Fe2-Tf decreased linearly with increasing glycation (r = 0.97; P = 0.008). Preincubation, independent of glycation, favored the Fe1N-Tf isoform at 64% theoretical Fe3+ saturation [27 (0.7)% vs 23 (1.1)% of the Fe1C-Tf isoform; P = 0.009].Conclusions: Glycation impairs Fe3+ binding and affects Fe3+-Tf isoform distribution depending on concentration. The diagnostic implications of these results need further elucidation in clinical studies.
Effect of Ceramic Particle Additions on Foam Expansion and Stability in Compacted Al‐TiH2 Powder Precursors
Authors: Kennedy A.R. , Asavavisithchai S. 
Published: July 2004

AbstractAl2O3, SiC and TiB2 particles have been added to Al‐0.6 wt.% TiH2 powder mixtures. The resulting precursors were foamed and it was found that by adding as little as 3 vol. % of particles, the maximum foam expansion was increased from 350 % to 450 %. Microstructural investigations revealed that particles enhance foam expansion through a reduction in the critical cell wall thickness before rupture. The presence of oxide in the molten powder system tends to prevent good wetting, the ceramic phase is usually located at the cell walls, protruding into the cells and does not prevent drainage of liquid through the cell structure. An exception to this case was observed in the Al‐SiC system where wetting is good and enhanced by reaction between the two phases. In this system the ceramic does not protrude into the cells and the rate of drainage is significantly reduced, giving improved foam stability.
Endogenous Particle Stabilization During Magnesium Integral Foam Production
Authors: Körner C. , Hirschmann M. , Bräutigam V. , Singer R.F. 
Published: July 2004

AbstractThe production of magnesium integral foam components with a dense shell and a porous core is investigated. High pressure casting methods are used where liquid magnesium mixed with a blowing agent is injected into a permanent steel mould. A compact shell develops due to fast cooling at the walls. Larger cooling times in the core allow the decomposition of the blowing agent and the evolution of a foam structure. The resulting integral foams show a high weight‐specific stiffness combined with high energy absorption capability. For the first time, foam stabilizing without additives is realized. Stabilization is by foaming during solidification with the primary α‐phase particles acting as obstacles slowing down cell wall thinning.
Gasar—A new Class of Porous Materials
Authors: Shapovalov V. , Boyko L. 
Published: July 2004

AbstractThe paper summarizes published data and also deals with technology, structure, applications, and properties of gasars – new porous materials based on original findings obtained by authors. The method consists of melting a material in a gas atmosphere to saturate it with hydrogen and directional solidifying under strictly controlled thermodynamic and kinetic conditions. The materials produced by this method, have a monolithic matrix and pores of proper geometric shapes, providing to gasars higher strength, plasticity, thermal and electrical conductivities as compared with those of other porous materials. Gasar is recommended for prospective application as filters, bearings, metal‐matrix composites.
Fabrication of Lotus‐type Porous Metals and their Physical Properties
Authors: Nakajima H. , Ikeda T. , Hyun S.K. 
Published: July 2004

AbstractLotus‐type porous metals whose long cylindrical pores are aligned in one direction were fabricated by unidirectional solidification in a pressurized gas atmosphere. The pores are formed as a result of precipitation of supersaturated gas when liquid metal is solidified. The lotus‐type porous metals with homogeneous size and porosity of the evolved pores produced by a mould casting technique are limited to the metals with high thermal conductivity. On the other hand, the pores with inhomogeneous pore size and porosity are evolved for metals and alloys with low thermal conductivity such as stainless steel. In order to obtain uniform pore size and porosity, a new “continuous zone melting technique” was developed to fabricate long rod‐ and plate‐shape porous metals and alloys even with low thermal conductivity. Mechanical properties of tensile and compressive strength of lotus‐type porous metals and alloys are described together with internal friction, elasticity, thermal conductivity and sound absorption characteristics. All the physical properties exhibit significant anisotropy. Lotus‐type porous iron fabricated using a pressurized nitrogen gas instead of hydrogen exhibits superior strength.
Fracture of Metal Foams: In‐situ Testing and Numerical Modeling
Authors: Onck P.R. , van Merkerk R. , De Hosson J.Th.M. , Schmidt I. 
Published: July 2004

AbstractThis paper is on a combined experimental/modeling study on the tensile fracture of open‐cell foams. In‐situ tensile tests show that individual struts can fail in a brittle or ductile mode, presumably depending on the presence of casting defects. In‐situ single strut tests were performed, enabling observation of deformation and fracture behavior and, in addition, serving as calibration for the proposed single‐strut model. The single strut model consists of beam elements to account for elasticity and plasticity, and of special‐purpose fracture elements to account for failure. The model is demonstrated for a characteristic loading configuration, combining stretching and bending.
Processing of Titanium Foams
Authors: Dunand D. C. 
Published: July 2004

AbstractBecause of their excellent mechanical properties, low density and biocompatibility, titanium foams are attractive for structural and biomedical applications. This paper reviews current techniques for titanium foam processing, which are all based on powder‐metallurgy because of the extreme reactivity of liquid titanium. A first group of processes is based on powder sintering with or without place‐holder or scaffolds. A second group relies on expansion of pressurized pores created during prior powder densification.
Tuning and control of dimensional consistency in molded products
Authors: Kazmer David , Lotti Cybele , Bretas Rosario E. S. , Zhu Liang 
Published: July 2004

AbstractDesign and manufacturing of molded products are subject to uncontrolled variation (noise) and unknown performance behavior and/or requirements (uncertainty). The validity of current Six Sigma approaches for tolerancing and process optimization for multiple part dimensions is explored. Response surfaces for part weight and two part dimensions are developed as a function of multiple process variables for a rectangular part molded of isotactic polypropylene, i‐PP. The process capabilities with respect to dimensional consistency and part weight are assessed using standard practices and Monte Carlo analysis. With respect to tuning of manufacturing processes, multicriteria optimization is necessary to ensure the selection of process set‐points resulting in an acceptable likelihood of satisfying multiple dimensional specifications. The Extensive Simplex Method is shown to provide reasonable decision support for process optimization based on a linear process model derived from a main effects design of experiments. With respect to on‐line quality control of dimensional consistency, part weight was validated as a good estimator of part dimensions, though requiring validation on an application by application basis. © 2004 Wiley Periodicals, Inc. Adv Polym Techn 23: 163–175, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20007
High temperature copolymerization of styrene/ethyl acrylate: Reactivity ratio estimation in bulk and solution
Authors: Sahloul Nahla , Penlidis Alexander 
Published: July 2004

AbstractStyrene/ethyl acrylate (Sty/EA) free‐radical copolymerizations have been conducted in bulk with and without initiator and in solution using p‐xylene and m‐xylene (30 wt% and 60 wt% solvent level) at 100°C and 130°C. The monomer reactivity ratio values and their temperature dependence have been determined from low conversion copolymer composition data using the computer software package RREVM, which is based on the error in variables model (EVM) method. Copolymer composition data at low conversion confirmed the Mayo–Lewis model at both temperatures. The reactivity ratio values of the Sty/EA system do not seem to change with dilution by nonpolar solvents at low concentration from the reactivity ratio values obtained in bulk with and without initiator. However, xylene isomers were found to have a slight effect on the reactivity ratio value of ethyl acrylate when high solvent concentration was utilized. © 2004 Wiley Periodicals, Inc. Adv Polym Techn 23: 186–195, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20009
Submicron structured polymethyl methacrylate/acrylonitrile–butadiene rubber blends obtained via gamma radiation induced “in situ” polymerization
Authors: Spadaro G. , Dispenza C. , Mc Grail P. T. , Valenza A. , Cangialosi D. 
Published: July 2004

AbstractThe morphology and properties of PMMA/rubber blends, obtained through gamma radiation induced “in situ” polymerization of methyl methacrylate (MMA) in the presence of small quantities of an acrylonitrile–butadiene based rubber (ABN), are presented. Different systems have been obtained by irradiating at a fixed irradiation dose rate and temperature, varying the integrated dose. All the blends obtained were characterized with respect to their melt state and solid state dynamic‐mechanical response and mechanical tensile properties. In particular, the effect on the blend properties of prolonging the irradiation time was investigated. Furthermore, a morphological characterization through atomic force microscopy (AFM) was performed in order to determine how the irradiation conditions affect the ABN rubber particle size and distribution. Finally, the stability of the obtained morphologies was investigated by performing post‐irradiation thermal treatments at a temperature close to the glass transition of pure PMMA. © 2004 Wiley Periodicals, Inc. Adv Polym Techn 23: 211–221, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20010
Temperature dependence of electrical conductivity in poly(maleic anhydride‐alt‐acrylic acid) and its transition metal complexes
Authors: Kavlak Serap , Kodolbaş Alp Osman , Can Hatice Kaplan , Güner Ali , Rzaev Zakir M. O. 
Published: July 2004

AbstractPoly(maleic anhydride‐alt‐acrylic acid) and its transition‐metal complexes with Ni(II), Cu(II), and Cd(II) were synthesized. Poly(maleic anhydride‐alt‐acrylic acid) was characterized using Fourier transform infrared (FTIR), titration, viscometry, differential scanning calorimetry (DSC), and thermogravimetric (TGA) analysis. The temperature dependence of the conductivity of the copolymer and polychelates of transition metals was investigated between 300 and 453 K. The polychelates and copolymers were also analyzed by using FTIR spectroscopy before and after transition point. The observed conductivity followed by a semiconductor behavior with increasing temperature is discussed in relation to the presence of transition‐metal ions. © 2004 Wiley Periodicals, Inc. Adv Polym Techn 23: 222–229, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20012
Effect of calcite and calcite/zeolite hybrid fillers on LLDPE and PP composites
Authors: Kundu Patit P. , Biswas Jagnnath , Kim Hyun , Shim Sang Eun , Choe Soonja , Lee Dai Soo 
Published: July 2004

AbstractThe comparative tensile and impact properties and fracture morphologies between calcite and calcite/zeolite (hybrid) filled linear low‐density polyethylene (LLDPE) and polypropylene (PP) composites have been studied. The incorporation of fillers into LLDPE, whether calcite or calcite/zeolite hybrid fillers, does not alter the Tm of LLDPE, but slightly reduces the Tm of PP. The melting peak area representing the heat of fusion of the crystal decreases with fillers; the effect of the calcite and the hybrid filler would be the same. The impact strength, Young's modulus, and yield stress of the calcite and the hybrid filled LLDPE increased, indicating a reinforcing effect of the fillers. In addition, the filled LLDPE decreases in elongation at break (EB) and ultimate tensile strength. However, the hybrid LLDPE composite exhibits slightly higher Young's modulus and ultimate tensile strength than the calcite one, while the same values of impact strength and yield stress were observed. In the PP system, the Young's modulus is enhanced, whereas the rest of the mechanical properties were reduced. From SEM photomicrographs of the hybrid filled composites, the tensile fractured surface of LLDPE dumbbell bar exhibits tearing surfaces while the composite shows formation of air holes and cracks in the LLDPE and PP system, respectively. Because of improved Young's modulus, yield strength, impact strength, and morphological observation along with substantial extension, the filled LLDPE composite with calcite/zeolite hybrid fillers is worth using for micro‐porous film applications. © 2004 Wiley Periodicals, Inc. Adv Polym Techn 23: 230–238, 2004; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/adv.20013
Sampling Fauna in Stream Sediments as well as Groundwater Using One Net Sampler
Authors: Schmidt Susanne I. , Hahn Hans J. , Watson Gerald D. , Woodbury Robert J. , Hatton Thomas J. 
Published: July 2004

AbstractGroundwater bores act as traps. Net samplers are regularly used for sampling this type of trap for fauna. To enable direct comparisons of faunal communities in groundwater bores and stream sediments, stream sediment tubes were built similar to groundwater bores and were sampled with net samplers for fauna. These stream sediment tubes consisted of a tube anchored in the stream sediment, also called interstitial space.To test the efficacy of this trap method in stream sediments, it was compared to another type of trap, Hahn's trap. Faunal communities sampled by a net in the stream sediment tubes did not differ hugely from fauna in Hahn's trap samples. Physical and chemical factors of sampled water in both the stream sediment tubes, the surrounding interstitial sediments and the second type of traps, Hahn's traps, showed that water in both the tubes and Hahn's traps was closely related to interstitial water.The net sampler is inexpensive and easy to handle. It is suggested that sampling stream tubes with nets may be an appropriate method for long‐term monitoring studies.
Impinging jet cooling on concave surfaces
Authors: Souris N. , Liakos H. , Founti M. 
Published: July 2004

AbstractThe numerical modeling of jet impingement cooling onto a semicircular concave surface is reported. The performance of two‐equation turbulence models (such as the k–ε model) is evaluated vs. the Reynolds stress model proposed. The Reynolds‐averaged momentum and energy equations are solved together with equations for the turbulence models, using a fully unstructured control volume method and a second‐order high‐resolution differencing scheme. Variations of jet Reynolds numbers of the spacing between the nozzle and the concave surface, as well as of the distance from the stagnation point in the circumferential direction, are considered. The predicted results are validated against experimental data. The developed approach yields low‐cost and accurate predictions of processes where jet impingement cooling is involved. It can assist the design of relevant applications, with relative ease, especially in view of the enhanced heat transfer encountered in the concave surface jet impingement. © 2004 American Institute of Chemical Engineers AIChE J, 50: 1672–1683, 2004
Genomic imprinting and environment in hereditary paraganglioma
Authors: Baysal Bora E. 
Published: July 2004

AbstractHereditary paraganglioma (PGL) is characterized by the development of slow‐growing and vascularized tumors in the paraganglionic system. PGL is caused by germ line heterozygous inactivating mutations in the SDHB (PGL4), SDHC (PGL3), or SDHD (PGL1) genes, which encode three of the four subunits of mitochondrial complex II (succinate dehydrogenase; SDH). Common tumor sites include the carotid body in the neck and paraganglia in the abdomen. The risk of tumor development associated with SDHD mutations is determined by the sex of the transmitting parent, because only a paternal transmission leads to tumorigenesis in the progeny. This transmission pattern suggests operation of genomic imprinting on the SDHD gene. There is also evidence that the risk of tumor development increases at higher altitudes among SDHD mutation carriers. Accordingly, the increased prevalence of SDHD mutations in the Netherlands, attributable to multiple founder mutations, has been explained in part by the low altitudes in this country, which presumably reduce gene penetrance and relax the natural selection. Thus, PGL caused by SDHD mutations represents an unusual example of an inherited monogenic tumor syndrome because the risk of tumorigenesis shows an absolute dependence on the sex of the transmitting parent and may be modified by a ubiquitous environmental factor. © 2004 Wiley‐Liss, Inc.
Loss of DNA mismatch repair function and cancer predisposition in the mouse: Animal models for human hereditary nonpolyposis colorectal cancer
Authors: Edelmann Lisa , Edelmann Winfried 
Published: July 2004

AbstractGermline mutations in DNA mismatch repair genes underlie one of the most common hereditary cancer predisposition syndromes known in humans, hereditary nonpolyposis colorectal cancer (HNPCC). Defects of the DNA mismatch repair system are also prevalent in sporadic colorectal cancers. The generation of mice with targeted inactivating mutations in the mismatch repair genes has facilitated the in vivo study of how these genes function and how their individual loss contributes to tumorigenesis. Although there are notable limitations when using murine models to study the molecular basis of human cancer, there is remarkable similarity between the two species with respect to the contribution of individual members of the mismatch repair system to cancer susceptibility, and mouse mutants have greatly enhanced our understanding of the normal role of these genes in mutation avoidance and suppression of tumorigenesis. © 2004 Wiley‐Liss, Inc.
Retinoblastoma: Revisiting the model prototype of inherited cancer
Authors: Lohmann Dietmar R. , Gallie Brenda L. 
Published: July 2004

AbstractHereditary retinoblastoma is an autosomal dominant disorder caused by mutations in the RB1 gene. Analysis of this rare condition has helped to elucidate the mechanisms underlying hereditary cancer predisposition in general. As identification of RB1 gene mutations has become a part of clinical management of patients with retinoblastoma, there is now a wealth of data. In this article, we summarize the current knowledge on the relations between the genotype and phenotypic expression. Moreover, detailed analysis of genotype–phenotype relations shows that hereditary retinoblastoma has features of a complex trait. © 2004 Wiley‐Liss, Inc.
Familial Wilms tumor
Authors: Ruteshouser E. Cristy , Huff Vicki 
Published: July 2004

AbstractWilms tumor (WT), an embryonic tumor arising from undifferentiated renal mesenchyme, has been a productive model for understanding the role of genes in both tumorigenesis and normal organogenesis. Approximately 2% of WT patients have a family history of WT, and even sporadic WT is thought to have a strong genetic component to its etiology. Familial WT cases generally have an earlier age of onset and an increased frequency of bilateral disease, although there is variability among WT families, with some families displaying later than average ages at diagnosis. One WT gene, WT1 at 11p13, has been cloned, but only a minority of tumors carry detectable mutations at that locus, and it can be excluded as the predisposition gene in most WT families. Two familial WT genes have been localized, FWT1 at 17q12–q21 and FWT2 at 19q13.4; lack of linkage in some WT families to either of these loci implies the existence of at least one additional familial WT gene. Originally modeled as the inheritance of a mutation in a tumor suppressor gene, molecular analysis of familial tumors not linked to 11p13 have provided data suggesting that this model may be overly simplistic and/or not applicable to all WT families. Identification of the FWT1 and FWT2 genes will help clarify this and will also likely aid in our understanding in general of the roles of the various WT genes and their genetic interactions in the development of WT. © 2004 Wiley‐Liss, Inc.