bluuebunny/crossref_metadata_2025_split huggingface dataset:
Application of a second‐order Runge–Kutta discontinuous Galerkin scheme for the shallow water equations with source terms
Authors: Kesserwani G. , Ghostine R. , Vazquez J. , Ghenaim A. , Mosé R. 
Published: June 2007

AbstractThe present work addresses the numerical prediction of discontinuous shallow water flows by the application of a second‐order Runge–Kutta discontinuous Galerkin scheme (RKDG2). The unsteady flow of water in a one‐dimensional approach is described by the Saint Venant's model which incorporates source terms in practical applications. Therefore, the RKDG2 scheme is reformulated with a simple way to integrate source terms. Further, an adequate boundary conditions handling, by the theory of characteristics, was overviewed to be adapted to the external points of the mesh, as well as to some points of local invalidity of the Saint Venant's model. To validate the proposed technique, steady and transient test problems (all having a reference solution) were considered and computed by means of the overall method. The results were illustrated jointly with the reference solution and the results carried out by a traditional second‐order finite volume (FV2) scheme implemented with the same techniques as the RKDG2. The proposed method has proven its practical consideration when solving discontinuous shallow water flow involving: non‐prismatic channels, various cross‐sections, smoothly varying bed topography and internal boundary conditions. Copyright © 2007 John Wiley & Sons, Ltd.
Numerical simulation of minimum B‐jumps at abrupt drops
Authors: Tokyay Nuray Denli , Altan‐Sakarya A. Burcu , Eski Elvan 
Published: June 2007

AbstractA numerical simulation of minimum B‐jumps in horizontal rectangular channels having an abrupt drop is given. Gradually varied, steady, supercritical flow is assumed as the initial condition. An unsteady flow is created by increasing the downstream depth. One‐dimensional, unsteady Saint‐Venant equations are solved by using the MacCormack and the dissipative two–four explicit finite difference schemes. The steady flow solution is obtained by treating the time variable as an iteration parameter and letting the solution converge to the steady state. The abrupt drop is treated as an interior boundary and solved by the method of characteristics. The results are compared with experimental and analytical studies. Copyright © 2007 John Wiley & Sons, Ltd.
AN examination of short QQQ option trades
Authors: Simon David P. 
Published: June 2007

AbstractThis study shows that unconditional QQQ option selling strategies from January 2001 through November 2004 are generally significantly profitable after transactions costs. However, when straddle and strangle sales are combined with purchases of out of the money puts, few of the strategies are significantly profitable. Profits improve when the QQQ Volatility Index is high relative to time series volatility forecasts, but only when actual volatility is forecast to be moderate. Active delta‐hedging reduces profitability, whereas stop loss/take profit orders enhance profitability. Overall, QQQ short volatility trades appear to be less compelling than what others have found with S&P options. © 2007 Wiley Periodicals, Inc. Jrl Fut Mark 27:739–770, 2007
Mild cognitive impairment: coping with an uncertain label
Authors: Joosten‐Weyn Banningh Liesbeth , Vernooij‐Dassen Myrra , Rikkert Marcel Olde , Teunisse Jan‐Pieter 
Published: June 2007

AbstractBackgroundThe recently introduced diagnostic label of Mild Cognitive Impairment (MCI) identifies patients with a cognitive decline that is more pronounced than is usual for a person's age and educational level but does not notably interfere with activities of daily living (ADL). The natural course of the syndrome is uncertain although MCI sufferers have a higher risk of developing dementia.ObjectivesTo investigate how patients fulfilling MCI criteria experience and cope with their cognitive decline with the secondary aim to derive key themes for a prospective MCI support‐group programme.MethodsThe grounded theory approach.ResultsAnalysis of guided interviews with eight MCI patients revealed four common themes. Changes related to cognitive abilities, mobility, affect, vitality and somatic complaints. Attributions were numerous and concerned aetiologies such as personality traits and overload of information. Consequences were all negative and concerned the patients themselves such as anxiety and loss of self‐confidence, others such as feelings of irritation and anger towards others or activities like abandoning leisure activities. Patients applied emotion‐oriented, problem‐focused and avoidant coping strategies.ConclusionMCI patients encounter stress‐inducing practical, social and psychological difficulties. Based on the current preliminary findings, the key themes for an MCI support‐group programme should include the provision of information about the syndrome's causes, course, concomitant symptoms, attributions, social consequences, and available treatments. The impact of receiving an MCI label warrants further investigation. Copyright © 2007 John Wiley & Sons, Ltd.
Surface properties and implantation site affect the capsular fibrotic overgrowth
Authors: Bakeine G.J. , Bertolotti A. , Latina M. , Congiu T. , Prati U. , Roveda L. , Trotta F. , Tormen M. , Fabrizio E. Di , Carlini G. , Facoetti A. , Nano R. 
Published: June 2007

AbstractTransplantation of encapsulated pancreatic islets is a promising approach for the treatment of type 1 diabetes. Large‐scale application of this technique, however, is hampered by insufficient biocompatibility of the capsules. In this study, we have evaluated the biocompatibility of a new synthetic material with six different chemical groups on their surface (amino, carboxy‐sulfate, carboxylate, hydroxylate, sulfate, and PMMA) used for the fabrication of the microcapsules. Eight Lewis rats were inoculated with a suspension of empty capsules made for each candidate material in the retroperitoneal ileopsoas muscle and renal subcapsular space. Four weeks later kidney and muscle containing the capsules were explanted, paraffin embedded, sectioned and stained with Sirius Red and Masson's Trichrome for histological analysis. The amount of fibrosis was also ultrastructurally evaluated with scanning electron microscopy. The samples were then subjected to digitalized quantitative analysis using specific software to determine the degree of fibrotic overgrowth. The quantification of collagen deposition, calculated in proximity of the microcapsules, was expressed as a percentage of the total area and can be considered a good index for the biocompatibility, an essential prerequisite for functional pancreatic islet transplantation. The results show that subcapsular renal space is the best implantation site and the positive surface charge induces a more intense collagen synthesis. © 2007 Wiley Periodicals, Inc. J Biomed Mater Res, 2007
Parabiosis and transplantation models show no evidence of circulating dermal fibroblast progenitors in bleomycin‐induced skin fibrosis
Authors: Boban Ivana , Barisic‐Dujmovic Tatjana , Clark Stephen H. 
Published: June 2007

AbstractTo test the hypothesis of an extra‐dermal origin of dermal fibroblasts, parabiosis, and transplantation models were developed utilizing a collagen promoter green fluorescent protein (GFP) reporter transgene expressed in dermal fibroblasts. Parabiotic pairs were treated with bleomycin to induce the skin fibrosis that was evaluated for a dense deposition of collagen and inflammatory cell infiltrates in the thickened dermis in comparison with parabiotic pairs treated with saline. Although, in all cases, repeated injection of bleomycin for 4 weeks induced skin fibrosis, only a few GFP positive cells were detected in skin samples from some of the treated non‐transgenic mice. Unexpectedly, similar results were observed in saline treated controls. Furthermore, bone marrow chimeras were created in which non‐transgenic recipient mice received injections of bone marrow cell preparations isolated from pOBCol3.6GFP transgenic mice. After bone marrow chimerism had been successfully established, fibrotic lesions in the skin were induced by local bleomycin injections. Donor GFP expressing cells were observed in the skin from all recipient mice. However, no difference in the presence of GFP expressing cells was observed between non‐treated mice or mice treated with bleomycin or saline. A large number of GFP expressing cells were observed in the lung preparations from all chimeric mice. Mac‐3 antibody immunostaining confirmed a macrophage phenotype for these GFP expressing cells suggesting the expression of the pOBCol3.6GFP transgene in a non‐collagen producing cell. Based on these observations, we found no evidence of circulating dermal fibroblast progenitors that participate in the development of bleomycin‐induced skin fibrosis. J. Cell. Physiol. 214:230–237, 2008. © 2007 Wiley‐Liss, Inc.
Syndecan‐1 interaction with the LG4/5 domain in laminin‐332 is essential for keratinocyte migration
Authors: Bachy Sophie , Letourneur François , Rousselle Patricia 
Published: June 2007

AbstractLaminin 5/laminin 332 (LN332) is an adhesion substrate for epithelial cells. After secretion of LN332, a regulated cleavage occurs at the carboxy‐terminus of its alpha3 subunit, which releases a tandem of two globular modules named LG4/5. We show that the presence of the LG4/5 domain in precursor LN332 decreases its integrin‐mediated cell adhesion properties in comparison with mature LN332. Whereas cell adhesion to the recombinant LG4/5 fragment relies solely on the heparan sulfate proteoglycan (HSPG) receptor syndecan‐1, we reveal that both syndecan‐1 and the alpha3beta1 integrin bind to precursor LN332. We further demonstrate that syndecan‐1 mediated cell adhesion to the LG4/5 fragment and pre‐LN332 allows the formation of fascin‐containing protrusions, depending on the GTPases Rac and Cdc42 activation. Reducing syndecan‐1 expression in normal keratinocytes prevents cell protrusions on pre‐LN332 with subsequent failure of the peripheral localization of the alpha3beta1 integrin. We finally show that cell migration on pre‐LN332 requires syndecan‐1. Therefore, the LG4/5 domain in precursor LN332 appears to trigger intracellular signaling events, which participate in keratinocyte motility. J. Cell. Physiol. 214:238–249, 2008. © 2007 Wiley‐Liss, Inc.
PI3‐K/Akt‐dependent activation of cAMP‐response element‐binding (CREB) protein in Jurkat T leukemia cells treated with TRAIL
Authors: Caravatta Luciana , Sancilio Silvia , di Giacomo Viviana , Rana Rosalba , Cataldi Amelia , Di Pietro Roberta 
Published: June 2007

AbstractWe recently demonstrated the activation of phosphatidylinositol 3‐kinase (PI3‐K/Akt) survival pathway in Jurkat T leukemia cells known for their sensitivity to the tumor necrosis factor (TNF)‐related apoptosis‐inducing ligand (TRAIL)/Apo2L cytotoxic action. The present investigation was done to elucidate the role of cAMP‐response element‐binding (CREB) protein in this system. Jurkat T cells were treated with 100–1,000 ng/ml TRAIL for time intervals up to 24 h in the presence or absence of selective pharmacologic inhibitors of PI3‐K/Akt (LY294002) or p38 MAPK (SB253580) pathways. Upon TRAIL treatment, a dose‐dependent increase in the percentage of apoptotic cells as well as in caspase‐3 activity was observed. A further enhancement of apoptotic cell death was obtained with the use of CREB1 siRNA technology, as demonstrated by flow cytometry. Western blot analysis showed a high constitutive level of CREB phosphorylation at Ser133 in Jurkat T cells under normal serum culture conditions. Under low serum culture conditions, an early (within 1 h) and transient increase in CREB phosphorylation was detected in response to both TRAIL doses and reduced upon pre‐treatment with LY294002 or SB253580, demonstrating the PI3‐K/Akt‐ and p38 MAPK‐dependency of this effect. The parallel analysis in immune fluorescence demonstrated the nuclear translocation of the phosphorylated form upon treatment with 100 ng/ml TRAIL, whereas the immune labeling was mainly detectable in the cytoplasm compartment upon the higher more cytotoxic dose. These results let us hypothesize that CREB activation can be an important player in the complex cross‐talk among pro‐ and anti‐apoptotic pathways in this peculiar cell model. J. Cell. Physiol. 214:192–200, 2008. © 2007 Wiley‐Liss, Inc.
Transcriptional regulation of pyruvate kinase and phosphoenolpyruvate carboxykinase in the adductor muscle of the oyster Crassostrea gigas during prolonged hypoxia
Authors: Le Moullac Gilles , Bacca Hélène , Huvet Arnaud , Moal Jeanne , Pouvreau Stéphane , Van Wormhoudt Alain 
Published: June 2007

AbstractThe response of Crassostrea gigas to prolonged hypoxia was investigated for the first time by analyzing the metabolic branch point formed by pyruvate kinase (PK) and hosphoenolpyruvate carboxykinase (PEPCK). PK and PEPCK cDNAs were cloned and sequenced. The main functional domains of the PK sequence, such as the binding sites for ADP/ATP and phosphoenolpyruvate (PEP), were identified whereas the PEPCK sequence showed the specific domain to bind PEP in addition to the kinase‐1 and kinase‐2 motifs to bind guanosine triphosphate (GTP) and Mg2+, specific for all PEPCKs. A C‐terminal extension was detected for the first time in eukaryota PK. Separation of mitochondrial and cytosolic fraction showed that more than 92% of the PEPCK enzyme activity was cytosolic in gills, digestive gland, mantle and muscle. PK and PEPCK mRNAs and enzyme activities have been measured in muscle during prolonged hypoxia for 20 days. Adaptation of PK in hypoxic muscle at transcriptional level occurred lately by decreasing significantly the PK mRNA level at day 20 while PK enzyme activity was inhibited by the high content of alanine. The PEPCK mRNA ratio in hypoxic muscle significantly increased at day 10 simultaneously to the PEPCK enzyme activity. Succinate accumulation observed at day 10 and day 20 confirmed the anaerobic pathway of muscle metabolism in oyster subjected to hypoxia. Regulation of C. gigas PEPCK in muscle occurred at gene transcription level while PK was first regulated at enzyme level with alanine as allosteric inhibitor, and then at molecular level under a fast effect of hypoxia. J. Exp. Zool. 307A:371–382, 2007. © 2007 Wiley‐Liss, Inc.
Are babies better in autumn or spring? The consequences of extending gestation in a biennially reproducing viviparous lizard
Authors: Atkins Natalia , Swain Roy , Jones Susan M. 
Published: June 2007

AbstractNiveoscincus microlepidotus, the southern snow skink, is a biennially reproducing alpine viviparous lizard with an extremely protracted gestation period: embryos are fully developed in autumn, but held over winter so that offspring are born in spring. The obvious benefits for offspring survival of delaying birth until spring have been demonstrated previously. To examine the consequences of deferred parturition for offspring characteristics, we compared neonates obtained in autumn by dissection with neonates born naturally in the spring. Our results demonstrate that deferral of parturition until spring represents a trade‐off between key offspring characteristics (spring neonates exhibit lower growth rates, reduced sprint speed after birth, reduced condition and decreased energy reserves) and offspring size [spring neonates are heavier (wet mass) and longer (snout‐vent length)]. Furthermore, when females are placed into cold experimental conditions in spring around the time of natural parturition, this species is able to defer parturition for an additional 4 weeks with no significant effect on offspring characteristics. Our results provide further evidence that flexibility in birth date provides a significant advantage to viviparous lizards living in cold climates. J. Exp. Zool. 307A:397–405, 2007. © 2007 Wiley‐Liss, Inc.
A stereophotographic study of ankle joint contact area
Authors: Millington Stephen , Grabner Markus , Wozelka Ralph , Hurwitz Shepard , Crandall Jeff 
Published: June 2007

AbstractThe purpose of this study was to measure the ankle joint contact area under physiological load magnitudes using a stereophotography technique that allows accurate analysis of the entire joint surface without disrupting the joint during loading. Ten cadaveric foot and ankle specimens were loaded to 1000 N in neutral, and 20° dorsiflexion, supination, pronation, and plantarflexion. Photo targets rigidly fixed to each of the bones were imaged in the loaded joint position using a high‐resolution stereophotography system. After testing, each ankle was disarticulated and the joint surfaces imaged relative to the photo targets. The photo targets were then used to spatially register the joint surfaces into the loaded joint position; the overlap of the surfaces was used to determine the joint contact area. The mean talo–tibia contact area was greatest in dorsiflexion 7.34 ± 1.69 cm2 and was significantly larger than in plantar flexion (p < 0.05), which showed the smallest joint contact area 4.39 ± 1.41 cm2. Considering talo–fibula, the maximum contact area was measured in dorsiflexion, 2.02 ± 0.78 cm2, and the minimum contact area occurred in pronation, 0.77 ± 0.49 cm2, respectively (p < 0.05). The reported stereophotography technique allows measurement of the joint contact area without disrupting the joint during loading. The contact area is larger than previously reported, as the entire joint surface was analyzed. Joint contact extends over both the talar dome and the talar shoulders where osteochondritis dissecans lesions commonly occur. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1465–1473, 2007
Microtopography of metal surfaces influence fibroblast growth by modifying cell shape, cytoskeleton, and adhesion
Authors: Meredith David O. , Eschbach Lukas , Riehle Mathis O. , Curtis Adam S. G. , Richards Robert G. 
Published: June 2007

AbstractStainless Steel (SS), titanium (cpTi), and Ti‐6Al‐7Nb (TAN) are frequently used metals in fracture fixation, which contact not only bone, but also soft tissue. In previous soft tissue cytocompatibility studies, TAN was demonstrated to inhibit cell growth in its “standard” micro‐roughened state. To elucidate a possible mechanism for this inhibition, cell area, shape, adhesion, and cytoskeletal integrity was studied. Only minor changes in spreading were observed for cells on electropolished SS, cpTi, and TAN. Cells on “standard” cpTi were similarly spread in comparison with electropolished cpTi and TAN, although the topography influenced the cell periphery and also resulted in lower numbers and shorter length of focal adhesions. On “standard” microrough TAN, cell spreading was significantly lower than all other surfaces, and cell morphology differed by being more elongated. In addition, focal adhesion numbers and mean length were significantly lower on standard TAN than on all other surfaces, with 80% of the measured adhesions below a 2‐µm threshold. Focal adhesion site location and maturation and microtubule integrity were compromised by the presence of protruding β‐phase microspikes found solely on the surface of standard TAN. This led us to propose that the impairment of focal adhesion numbers, maturation (length), and cell spreading to a possibly sufficient threshold observed on standard TAN blocks cell cycle progress and eventually cell growth on the surface. We believe, as demonstrated with standard cpTi and TAN, that a difference in surface morphology is influential for controlling cell behavior on implant surfaces. © 2007 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 25:1523–1533, 2007
Functional Star‐Like Polystyrenes as Organic Supports of MeDIP(2,6‐iPrPh)2FeCl2 Catalyst Toward Ethylene Polymerization
Authors: Bouilhac Cécile , Cloutet Eric , Deffieux Alain , Taton Daniel , Cramail Henri 
Published: June 2007

AbstractStar‐like polystyrenes composed of a microgel core with functionalized arms have been designed and used as organic supports for a tridentate bis(imino)pyridinyl iron catalyst toward ethylene polymerization. In a first approach, star‐like polystyrenes bearing a few number of ethylene oxide units at the periphery of each arm have been prepared to immobilize, through nucleophilic interactions, common aluminum‐based activators [methylaluminoxane or trimethylaluminum (TMA)]. A second strategy is based on the synthesis of star‐like PS with arms ended either by a benzophenone or a benzoic acid function. Indeed, the reaction of TMA with these functional microgels leads to the in situ formation of alkoxide aluminum‐based species at the periphery of the star‐like microgels. All these functional PS microgels have been used as supports to immobilize and activate the MeDIP(2,6‐iPrPh)2FeCl2 catalyst toward ethylene polymerization. High catalytic activities and polyethylene beads of spherical morphology, constituted of polyethylene chains of monomodal molar mass distribution have been obtained, thanks to the organic support.magnified image
A Feasible Synthetic Route for Linear PTHF‐Hyperbranched Poly(phenyl sulfide) Block Copolymers
Authors: Zhu Zhichen , Pan Caiyuan 
Published: June 2007

AbstractThe linear‐hyperbranched block copolymers, in which the linear polytetrahydrofuran (PTHF) is linked to the apex of hyperbranched poly(phenylene sulfide) (HPPS‐SH), have been synthesized, and the synthesis includes condensation polymerization of 2,4‐dichlorobenzenethiol, subsequent transformation of the resultant HPPS‐SH to HPPS‐OH, and then the cationic ring‐opening polymerization of tetrahydrofuran (THF) using HPPS‐OH as a macrotransfer agent and BF3 · OEt2 as a catalyst. The resultant HPPSs have excellent thermal stability, the PTHF and HPPS chains were decomposed at 361 and 402 °C, respectively. HPPS can be dissolved in THF in the form of aggregates with Rh = 90 nm, which is larger than that (Rh = 55 nm) formed from the corresponding linear PTHF‐HPPS block copolymer.magnified image
Effect of Polymer Architecture of Amphiphilic Poly(2‐oxazoline) Copolymers on the Aggregation and Aggregate Structure
Authors: Bonné Tune B. , Lüdtke Karin , Jordan Rainer , Papadakis Christine M. 
Published: June 2007

AbstractThe micelle formation of five poly(2‐oxazoline) diblock, triblock and gradient copolymers in water was investigated using fluorescence correlation spectroscopy. The polymers were synthesized by consecutive or simultaneous living cationic polymerization of 2‐methyl‐2‐oxazoline for the hydrophilic and 2‐nonyl‐2‐oxazoline for the hydrophobic polymer segments. Fractions of the polymers were fluorescence‐labeled at the polymer termini with TRITC for the FCS measurements. The hydrodynamic radii of solubilized polymer unimers and of the aggregates (micelles) were determined in a concentration range of 10−8–10−3 M and were found to depend in a characteristic way on the polymer architecture.magnified image
“Never eat in that restaurant, I did!”: Exploring why people engage in negative word‐of‐mouth communication
Authors: Wetzer Inge M. , Zeelenberg Marcel , Pieters Rik 
Published: June 2007

AbstractWhat do consumers want to achieve when they engage in negative word‐of‐mouth communication (N‐WOM)? Two studies explore this question and reveal that consumers pursue specific goals when engaging in N‐WOM and that these goals systematically differ between the specific negative emotions that are experienced. For example, the results reveal that consumers who experience anger engage in N‐WOM to vent feelings or to take revenge. However, disappointed consumers engage in N‐WOM to warn others, and consumers who experience regret communicate with others to strengthen social bonds or to warn them. This reveals the functionality of specific emotions to N‐WOM, and how goals for N‐WOM are associated with these emotions. This demonstrates that rather than being uniform, the content and implications of N‐WOM are contingent on the specific emotions that consumers experience. © 2007 Wiley Periodicals, Inc.