bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ethylene Polymerization Kinetics with a Heterogeneous Metallocene Catalyst – Comparison of Gas and Slurry Phases
Authors: Bergstra Michiel F. , Weickert Günter 
Published: June 2005

AbstractSummary: Ethylene homopolymerizations were executed with a supported Ind2ZrCl2/MAO catalyst using the so‐called Reactive Bed Preparation method. This RBP method combined a slurry polymerization with a gas phase polymerization with the same polymerizing particles, i.e., a reactive bed. Polymerization kinetics were measured with high accuracy and reproducibility. Slurry and gas phase polymerization rates showed the same dependency on monomer bulk concentration. A complexation model has been proposed to describe the non‐first order polymerization rate‐monomer concentration dependence observed. This model also explains the non‐Arrhenius temperature dependence and the observed pressure dependence of the activation energy of the commonly used polymerization rate model: Rp = kp · C* · M.
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Gas assisted injection molding of a handle: Three‐dimensional simulation and experimental verification
Authors: Polynkin A. , Pittman J.F.T. , Sienz J. 
Published: June 2005

AbstractMethods implemented in a three‐dimensional finite element code for the simulation of gas assisted injection molding are described, and predictions compared with the results of molding trials. The emphasis is on prediction of primary gas penetration and plastic wall thickness, including the effects of cooling during a delay before gas injection. For the latter, time dependent heat transfer coefficients at the cavity surface are used, determined in a separate analysis of transient heat conduction through the plastic and the mold tool to the circulating coolant. This shows how the initial value of 25,000 W/m2K falls by about an order of magnitude during the first few seconds of cooling, and also how values vary from cycle to cycle as steady periodic conditions are approached. For a tubular handle molded in polystyrene, with melt flow modeled by a Cross WLF model, comparisons of simulations with sectioned parts show excellent prediction of wall thickness and its variation circumferentially and in bends. The increase in wall thickness due to cooling during a gas delay is accurately modeled, as is the occurrence of a blow out. POLYM. ENG. SCI. 45:1049–1058, 2005. © 2005 Society of Plastics Engineers
Influence of interactions on the mechanical, morphological and thermal properties of in situ ternary composites based on fluorocarbon elastomer, acrylic elastomer and liquid crystalline polymer blends
Authors: Shivakumar E , Pandey KN , Alam S , Das CK 
Published: June 2005

AbstractThe mechanical, morphological and thermal properties of the binary and ternary blends of a fluorocarbon elastomer (FKM), an acrylic elastomer (ACM) and a liquid crystalline polymer (LCP) were investigated. The ternary blends were prepared by varying the amount of the LCP but fixing the ratio of the FKM and ACM. Addition of a third component, a polyacrylic rubber which interacted with the LCP, facilitated the structural development of the LCP phase by acting at the interface. The mechanical properties of the ternary blends were substantially improved because of both the fibril generation and adhesion of rubber particles on the LCP fibrils, which were attributed to the ACM interaction. Morphological investigations suggest that the fine fibrillation of the LCP domains is more apparent in the ternary blends than in the binary blends of FKM and LCP prepared under the same processing conditions. Thermogravimetric analysis (TGA) revealed an improved thermal stability of the FKM in the presence of the LCP for the binary blends, but a lower thermal stability for the ternary blends. Copyright © 2005 Society of Chemical Industry
Influence of molecular weight on liquid crystalline behavior of linear and star mesogen‐jacketed liquid crystal polymers
Authors: Wang Xingzhu , Zhang Hailiang , Chen Erqiang , Wang Xiayu , Zhou Qifeng 
Published: June 2005

AbstractA series of novel multi‐armed (di‐, tri‐ and tetra‐armed) mesogen‐jacketed liquid crystal polymers (MJLCPs) were synthesized by atom transfer radical polymerization (ATRP) of {2,5‐bis[(4‐methoxyphenyl)oxycarbonyl]styrene}(MPCS) using di‐, tri‐ and tetrafunctional initiator, respectively. The results show that the number average molecular weight (Mn,GPC) was increased versus monomer conversion, and the polydispersities were quite narrow (<1.19), which is the characteristic of controlled polymerization. The chemical structures of these multi‐armed mesogen‐jacketed liquid crystal polymers were confirmed by 1H NMR. The liquid crystalline behavior of these multi‐armed MJLCPs with arms ranging from two to four was studied by differential scanning calorimetry (DSC), polarized optical microscopy (POM) and wide‐angle X‐ray diffraction (WAXD). It was found that liquid crystalline phases appeared simply when the number molecular weights (Mn,GPC) of these multi‐armed MJLCPs was higher than a certain critical values, that is, Mn,GPC > 1.87 × 104 g/mol, 1.84 × 104 g/mol, 2.69 × 104 and 3.68 × 104 g/mol, which were initiated by coil difunctional initiator, hard difunctional initiator, trifunctional initiator and tetrafunctional initiator, respectively. All the liquid crystalline phase was found to be stable up to the decomposition temperature of these multi‐armed MJLCPs. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3232–3244, 2005
Effect of aniline formaldehyde resin on the conjugation length and structure of doped polyaniline: Spectral studies
Authors: Ho Ko‐Shan , Hsieh Tar‐Hwa , Kuo Chung‐Wen , Lee Swu‐Wen , Lin Jong‐Jing , Huang Ying‐Jie 
Published: June 2005

AbstractA DBSA (n‐dodecylbenzene sulfate)‐complexed aniline formaldehyde [AF(DBSA)1.0] was successfully synthesized with excess aniline (compared with formaldehyde) in the presence of n‐dodecylbenzene sulfonic acid (HDBSA), which was complexed with aniline monomer before polymerization. The resin was carefully characterized with 1H and 13C NMR, electron spectroscopy for chemical analysis, and Fourier transform infrared and was demonstrated to be a polymer in which anilines were all complexed with HDBSA and became anilinium salts. A drastic decrease of the maximum absorption wavelength (ultraviolet–visible spectra) of DBSA‐doped polyaniline [PANI(DBSA)0.5] was found when AF(DBSA)1.0 was mixed, and this resulted from the reduced conjugation length. A similar effect on PANI(DBSA)0.5 was found when free HDBSAs were mixed with PANI(DBSA)0.5. Visual inspection with an optical microscope revealed that PANI(DBSA)0.5/AF(DBSA)1.0 gave uniform morphologies in various compositions, showing possible miscibility for this system. X‐ray diffraction patterns of PANI(DBSA)0.5/AF(DBSA)1.0 showed that the layered structure of PANI(DBSA)0.5 was still present but became shorter in the polyblend because of the presence of AF(DBSA)1.0. Solid‐state 13C NMR spectra revealed that the reduced conjugation length was derived from the interaction of alkyl groups between HDBSA, complexed DBSA, and dopant DBSAs. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 3116–3125, 2005
Complementary medicine use by Australian women with gynaecological cancer
Authors: Markovic Milica , Manderson Lenore , Wray Natalie , Quinn Michael 
Published: June 2005

AbstractAims and objectives: Social and cultural factors are identified that impact on complementary therapy use among Australia‐born and immigrant women diagnosed with gynaecological cancer.Methods: A qualitative study design including in‐depth interviews with women diagnosed with gynaecological cancer (N=53) and participant observation was conducted.Results: Approximately one‐third of women utilized complementary and alternative medicine, with this being determined by current health concerns and health beliefs related to the efficacy of different modalities. Four types of complementary therapy users emerged: consequential, therapeutic, informed and exploratory.Conclusion: There was a relatively low uptake of complementary treatments. Choice was influenced by women's socio‐demographic background, clinical and personal history, lack of personal experiences of gynaecological cancer among study participants' kin and friends, and lack of popular alternative literature on such cancer. Copyright © 2005 John Wiley & Sons, Ltd.
Persistent tachypnea of infancy is associated with neuroendocrine cell hyperplasia
Authors: Deterding Robin R. , Pye Catherine , Fan Leland L. , Langston Claire 
Published: June 2005

AbstractWe sought to determine the clinical course and histologic findings in lung biopsies from a group of children who presented with signs and symptoms of interstitial lung disease (ILD) without identified etiology. Patients were identified from the pathology files at the Texas Children's Hospital who presented below age 2 years with persistent tachypnea, hypoxia, retractions, or respiratory crackles, and with nonspecific and nondiagnostic lung biopsy findings. Age‐matched lung biopsy controls were also identified. Their clinical courses were retrospectively reviewed. Biopsies were reviewed, and immunostaining with antibodies to neuroendocrine cells was done. Fifteen pediatric ILD patients and four control patients were identified for inclusion in the study. Clinically, the mean onset of symptoms was 3.8 months (range, 0–11 months). Radiographs demonstrated hyperinflation, interstitial markings, and ground‐glass densities. Oxygen was initially required for prolonged periods, and medication trials did not eliminate symptoms. After a mean of 5 years, no deaths had occurred, and patients had improved. On review of the lung biopsies, all had a similar appearance, with few abnormalities noted. Immunostaining with antibodies to neuroendocrine cell products showed consistently increased bombesin staining. Subsequent morphometric analysis showed that immunoreactivity for bombesin and serotonin was significantly increased over age‐matched controls. In conclusion, we believe this may represent a distinct group of pediatric patients defined by the absence of known lung diseases, clinical signs and symptoms of ILD, and idiopathic neuroendocrine cell hyperplasia of infancy. These findings may be important for the evaluation of ILD in young children. Pediatr Pulmonol. 2005; 40:157–165. © 2005 Wiley‐Liss, Inc.
Self‐assembly of GaAs holed nanostructures by droplet epitaxy
Authors: Wang Zhiming M. , Holmes Kyland , Shultz John L. , Salamo Gregory J. 
Published: June 2005

AbstractThe cover picture refers to the Rapid Research Letter by Zhiming M. Wang et al. [1] and displays the nanostructure evolution during GaAs growth by droplet epitaxy. The two colored AFM images of 2 µm × 2 µm show the formation of GaAs nano‐crystals shaped like lighted candles and square‐holed round coins.The first author, Zhiming M. Wang, is a research professor at the University of Arkansas, USA, and a member of the Molecular‐Beam Epitaxial group of Distinguished Professor Gregory J. Salamo. His current research interests include low‐dimensional semiconductor nanostructures, ferroelectronic and ferromagnetic nanostructures, and manipulation of single molecules.This issue of physica status solidi (a) also contains contributions from the 4th International Conference “Porous Semiconductors – Science and Technology”, held 14–19 March 2004 in Cullera (Valencia), Spain. Further papers from PSST‐2004 are published in phys. stat. sol. (c) 2, No. 9 (2005).
The Saccharomyces cerevisiae Sub2 protein suppresses heterochromatic silencing at telomeres and subtelomeric genes
Authors: Lahue Elaine , Heckathorn John , Meyer Zachary , Smith Jennie , Wolfe Christopher 
Published: June 2005

AbstractWe show that overexpression of Sub2p, a multifunctional Saccharomyces cerevisiae helicase family member that is involved in mRNA elongation and transport, also suppresses heterochromatic silencing at telomeres. Genetic assays show cells that overexpress SUB2 from a high copy plasmid exhibit increased survival rates when selecting for a telomere‐silenced URA3 reporter. Two temperature‐sensitive sub2 mutations that affect different helicase domains were also examined at the permissive temperature; these mutants also overcome silencing of the URA3 reporter. The degree to which silencing is suppressed correlates with SUB2 RNA and protein levels. Additionally, we find that Sub2p localizes to the telomeres, as determined by chromatin immunoprecipitation assays, suggesting that Sub2p has a direct effect at telomeres. Genome‐wide analysis of transcripts was used to assess whether Sub2p overproduction affects only the silenced URA3 reporter gene, or whether other subtelomeric genes are also affected. Of the 70 RNA transcripts elevated in the Sub2p overexpressing cells, 28% are encoded by subtelomeric genes that are located within 5 Kbp of a core X or Y′ repeat. The remainder of the transcripts clustered into several functional groups, including the iron homeostasis pathway, purine nucleotide metabolism, and miscellaneous transport genes, among others. These results suggest a targeted effect of Sub2p on transcription. Our results also confirm that Sub2p affects heterochromatic gene expression, similar to that observed with the Drosophila Hel25E homologue. The above observations imply that Sub2p affects chromatin structure in addition to, or in parallel with, its functions in transcription elongation, splicing and mRNA transport. Copyright © 2005 John Wiley & Sons, Ltd.
The ubiquitin ligase SCFGrr1 is necessary for pheromone sensitivity in Saccharomyces cerevisiae
Authors: Schweitzer Kelly , Cocklin Ross , Garrett Lisa , Desai Falguni , Goebl Mark 
Published: June 2005

AbstractThe presence of the appropriate pheromone induces α and a cells of the yeast Saccharomyces cerevisiae to activate both changes in transcriptional expression and cell polarity that eventually lead to the mating of α and a cells to form a/α diploid cells. A third response after exposure to mating pheromone is a transient cell cycle arrest, allowing synchronization of the two cell types in G1 prior to cell fusion. At least in part, this cell cycle arrest requires the inactivation of Cln‐kinase activity through transcriptional inactivation of the CLN1 and CLN2 genes, degradation of the Cln proteins and direct inhibition of Cln‐kinase complexes. Here we report that GRR1, which encodes a substrate recognition subunit of SCF complexes, is critical for pheromone sensitivity and likely for this arrest. Loss of SCFGrr1 function by deletion of the GRR1 gene causes pheromone resistance. However, deletion of CLN1 and CLN2 restores pheromone sensitivity to grr1Δ cells. Thus, rapid loss of Cln‐kinase activity during mating may require coordinated inactivation of the Cln‐kinase complexes, inactivation of CLN transcription and SCFGrr1‐dependent Cln degradation. Copyright © 2005 John Wiley & Sons, Ltd.
Riparian vegetation loss, stream channelization, and web‐weaving spiders in northern Japan
Authors: Laeser Scott R. , Baxter Colden V. , Fausch Kurt D. 
Published: June 2005

AbstractRemoval of riparian vegetation and straightening of stream channels (channelization) are the most prevalent forms of habitat degradation in streams and their riparian zones. Both have direct effects on organisms in the habitats where they occur, but also have potential to cause indirect effects by interrupting the flux of invertebrate prey between the two adjacent ecosystems. We measured abundance of web‐building riparian spiders along four types of streams in Hokkaido, Japan: relatively undisturbed streams, streams where riparian vegetation had been removed, previously channelized streams where the banks had revegetated, and streams that had been both channelized and had the vegetation removed. Spider abundance was reduced by 70% or more by either habitat disturbance alone, or both combined, and the number of spider families was also reduced. Spiders of the family Tetragnathidae, which specialize in capturing adult insects emerging from streams, were strongly reduced by either form of habitat degradation alone, or in combination. In contrast, abundance of spiders in other families that capture prey from both terrestrial and aquatic sources was reduced more strongly by vegetation loss than channelization. These results indicate that riparian vegetation loss has strong direct effects on spiders by reducing habitat for web sites. They also suggest that channelization can have strong indirect effects on riparian‐specialist tetragnathid spiders, probably by reducing the flux of adult aquatic insects from the stream to the riparian zone.
Patterns of Hand Fractures and Dislocations in A District General Hospital
Authors: PACKER G. J. , SHAHEEN M. A. 
Published: June 2005

In a retrospective survey of patients with fractures and dislocations attending the Accident department of a District General hospital, comparison was made between patients with fractures and dislocations in the hand and fractures and dislocations of other sites. Patients with hand injuries accounted for 28% of the total patients seen. They were more likely than other fracture patients to be male and between the ages of 10 and 40 years. Almost a quarter of hand injuries attended on Monday. Leisure activities outside the home formed the commonest aetiological factor. Only 66% of patients with hand injuries attended the Accident department within 24 hours of injury. The little finger was the commonest site of injury. This survey emphasizes the differences between hand injuries and injuries of other sites, identifies the risk factors for hand injuries and has implications for the management of hand injuries in a District General Hospital.
JAK—STAT signaling pathway in pulmonary arterial smooth muscle cells is activated by hypoxia
Authors: Wang Guan‐Song , Qian Gui‐Sheng , Zhou De‐Shan , Zhao Ji‐Qing 
Published: June 2005

AbstractPulmonary arterial smooth muscle cells (PASMC) were divided into a normoxic group (N), 2, 8 and 12 h hypoxic groups (H2, H8 and H12) and an AG490 plus 8 h hypoxic group (AG490). The expression of JAK1, JAK2, JAK3 and TYK2 mRNA was analyzed by reverse transcription‐polymerase chain reaction (RT‐PCR). STAT1 and STAT3 protein expressions were determined by Western blotting. The results showed that the levels of JAK1, JAK2 and JAK3 mRNA did not change significantly in the N group but were increased after 2 h exposure to hypoxia. JAK1, JAK2 and JAK3 mRNA expressions peaked at 8 h. It decreased at 12 h but remained above those in the N group. TYK2 mRNA was not found in either hypoxic or normal PASMC. The phospho‐STAT1 and ‐STAT3 protein levels increased after 2 h exposure to hypoxia. They were about 2.8 and 4.1 times the N group, respectively, after 8 h. They decreased at 12 h but remained above those in the N group. AG490 inhibited phospho‐STAT3 protein expression by about 25.5% at 8 h but did not block the expression of phospho‐STAT1 protein. These findings suggest that hypoxia induces the expression of JAK1, JAK2, JAK3 and phospho‐STAT1 and ‐STAT3 in PASMC. Hypoxia activates the JAKs—STATs signaling pathway, which may participate in the pathogenesis of hypoxic PASMC injury.
Pathways to caspase activation
Authors: Wang Zi‐Bing , Liu Yu‐Qing , Cui Yu‐Fang 
Published: June 2005

AbstractApoptosis or programmed cell death is an active form of cell death which is essential for tissue homeostasis. Many proteins are involved in the molecular signal transduction of apoptosis. The caspase enzymes, a family of specific cysteine proteases, play a central role in cell death machinery. In this review, we mainly discuss the current understanding of several pathways to activate caspases and some key proteins related to these pathways.
Analysis of prey size preference of North Sea whiting, saithe, and grey gurnard
Authors: Floeter Jens , Temming Axel 
Published: June 2005

Abstract
Size preference for prey fish of North Sea whiting, saithe, and grey gurnard was analysed. The analysis combined size-specific prey abundance estimates derived from bottom-trawl surveys with size frequencies of prey in predator stomachs from the International North Sea Stomach Database. To estimate the abundance of all potential prey fish in the sea, predator-specific length-based number spectra were calculated. Prey spectra were weighted by local predator abundance to take the spatial–temporal overlap between predator and their prey into consideration. Species-specific prey size preference models are presented. Contrary to former results, the preferred predator–prey weight ratio of whiting and grey gurnard is an exponentially increasing function of predator size and an exponentially decreasing function of the slope of the number spectrum. When predators grow, they prefer larger prey in absolute units. However, from a species-specific body size onwards they increasingly shift their prey preference towards relatively smaller prey sizes. From a bioenergetic point of view, this behaviour most likely maximizes the predator's foraging efficiency by reducing the expenditure of costly, anaerobically generated energy expended during burst swimming.
Seasonal cycles in weight and condition in Atlantic cod (Gadus morhua L.) in relation to fisheries
Authors: Mello L.G.S. , Rose G.A. 
Published: June 2005

Abstract
Seasonal cycle in weight and physiological condition of Atlantic cod (Gadus morhua) influenced productivity and economic impacts of the cod fishery in Placentia Bay, Newfoundland. Condition indices (Fulton's K condition factor and hepatosomatic index – HSI) were lowest during the spawning season (spring) and increased rapidly during the postspawning period, reaching maximum values by fall (K and HSI increased on average 24% and 82% between spring and fall, respectively). Somatic weight and condition indices varied seasonally. Condition indices were correlated with an industry index of product yield. Historically, cod fisheries have been prosecuted during all seasons, but simulations of 1997–1999 fisheries indicate that a fall fishery (period of peak physiological condition) resulted in a 8–17% decrease in the number of cod removed from the stock while maintaining the same weight-based quotas, and profiting from maximum yield and better product quality. Spring and summer fisheries resulted in lower yield (6%) and quality (5–26%) of fish products by weight. Seasonal biological cycles could be used as templates for management strategies that promote fisheries conservation and economic benefits by harvesting fish during periods when biological impacts are minimal and economic returns maximal.