bluuebunny/crossref_metadata_2025_split huggingface dataset:
Experimental and numerical analysis of flow behavior in the FASTRAC liquid composite manufacturing process
Authors: Allende Melquiades , Mohan Ram V. , Walsh Shawn M. 
Published: July 2004

AbstractThe success of resin infusion during liquid composite processing depends on several factors; including the complete impregnation of the dry performs, the processing conditions, and the tooling used during processing. New process developments based on the Fast Remotely Actuated Channels (FASTRAC) process aid the infusion with the creation of preferential resin flow paths using a non‐contact tooling. Experiments to understand and study the infusion behavior with the presence of the FASTRAC non‐contacting tooling have been performed, and compared with vacuum‐assisted processes without such tooling. Experimental studies indicate that the infusion time with FASTRAC channel configurations is significantly less despite the additional volume regions to be infused during processing. The use of a non‐contacting interchangeable tool, the improved infusion behavior, and the significant reduction in the infusion time provide significant advantages for processing advanced composite systems, including the potential to use high viscosity resin systems, and process automation. The process simulation models of the experimental configurations based on the thin shell model configurations have been compared with experimental observations. Studies indicate that the process simulation models and approaches employed clearly emulate the infusion behavior seen when the channels are present, validating the modeling strategies employed. Similar simulation approaches will thus be effective to study and understand various FASTRAC tooling configurations while processing complex composite structures. Polym. Compos. 25:384–396, 2004. © 2004 Society of Plastics Engineers.
Shielding effectiveness of carbon‐filled nylon 6,6
Authors: Heiser Jessica A. , King Julia A. , Konell Jeremiah P. , Sutter Lawrence L. 
Published: July 2004

AbstractElectrically conductive resins can be made by adding electrically conductive fillers to typically insulating polymers. Resins with an electrical resistivity of approximately 100 ohm‐cm or less can be used for electromagnetic and radio frequency interference shielding applications. This research focused on performing compounding runs followed by injection molding and shielding effectiveness testing of carbon filled nylon 6,6 based resins. The three carbon fillers investigated included an electrically conductive carbon black, synthetic graphite particles, and a surface‐treated polyacrylonitrile (PAN)‐based carbon fiber. Conductive resins were produced and tested that contained varying amounts of these single carbon fillers. In addition, combinations of fillers were investigated by conducting a full 23 factorial design and a complete replicate. The objective of this paper was to determine the effects and interactions of each filler on the shielding effectiveness properties of the conductive resins. Carbon fiber caused the largest increase in shielding effectiveness. Also, all the single fillers and combinations of fillers were statistically significant at the 95% confidence level, except the composite containing carbon black and synthetic graphite particles tested at 800 MHz. Polym. Compos. 25:407–416, 2004. © 2004 Society of Plastics Engineers.
Void transport in resin transfer molding
Authors: Kang Kai , Koelling Kurt 
Published: July 2004

AbstractThe transport of single drops through a hexagonal cylinder array is used to study the void movement and deformation in a resin transfer molding process. A transparent flow cell is used to visualize the transport of voids through a porous media model. Experiments are conducted with nearly inviscid water drops and viscous glycerol drops with drop sizes ranging from 0.4 to 80 μl, and with both a Newtonian fluid and Boger fluid with average resin velocities ranging from 0.011 to 0.140 cm/s. Two critical capillary numbers, which determine the breakup (Cab) and mobilization (Ca*) of drops, are measured to better understand the flow dynamics of voids. As demonstrated by the experiments, there is a critical drop size, below or above which a quite different flow behavior is observed. Such a transition is analyzed with consideration of the geometry characters in the flow field. Results expand the former studies in this area to a significantly larger range of drop sizes and capillary numbers. Particle Tracking Velocimetry is also used to quantify the local velocity, shear stress, extensional stress and energy dissipation in the flow field. Polym. Compos. 25:417–432, 2004. © 2004 Society of Plastics Engineers.
Parallel isoelectric focusing chip
Authors: Zilberstein Gleb , Korol Leonid , Bukshpan Shmuel , Baskin Emanuil 
Published: July 2004

AbstractFast isoelectric focusing (IEF) is becoming a key method in modern protein analysis. We report here the theory and experimental results of new parallel isoelectric devices (PID) for fast IEF. The main separation tool of any PID is a dielectric membrane with conducting channels filled by immobiline gels of varying pH. The pH value of the surrounding aqueous solution is not equal to the pH of any of the channels. The membrane is held perpendicular to the applied electric field. Proteins are collected (trapped) in the channels whose pH values are equal to the pI of the proteins. The fast particle transport between different channels takes place due to convection in the aqueous solution. We developed a mathematical model for PID. Experiment duration is shown to be proportional to the number of different bands N (the peak capacity in standard IEF) in contrast with N2 for usual IEF devices. This model was validated with experimental results. Parallel IEF accelerates the fractionation of proteins by their pI values (down to several minutes) allowing a more desirable collection efficiency to be achieved. The main theoretical limitation of PID resolution is the sensitivity of proteins to pH change due to the Coulomb blockade effect. The existence of a minimal pH change δpHmin for each type of protein is shown: δpHmin ∼ r−1 for globular molecules with radius r.
Homology‐based functional proteomics by mass spectrometry: Application to the Xenopus microtubule‐associated proteome
Authors: Liska Adam J. , Popov Andrei V. , Sunyaev Shamil , Coughlin Peg , Habermann Bianca , Shevchenko Anna , Bork Peer , Karsenti Eric , Shevchenko Andrej 
Published: July 2004

AbstractThe application of functional proteomics to important model organisms with unsequenced genomes is restricted because of the limited ability to identify proteins by conventional mass spectrometry (MS) methods. Here we applied MS and sequence‐similarity database searching strategies to characterize the Xenopus laevis microtubule‐associated proteome. We identified over 40 unique, and many novel, microtubule‐bound proteins, as well as two macromolecular protein complexes involved in protein translation. This finding was corroborated by electron microscopy showing the presence of ribosomes on spindles assembled from frog egg extracts. Taken together, these results suggest that protein translation occurs on the spindle during meiosis in the Xenopus oocyte. These findings were made possible due to the application of sequence‐similarity methods, which extended mass spectrometric protein identification capabilities by 2‐fold compared to conventional methods.
The principle of nonperfect synchronization: how does it apply to aromatic systems?
Authors: Bernasconi C. F. 
Published: July 2004

AbstractAccording to the Principle of Nonperfect Synchronization (PNS), a product‐stabilizing factor, the development of which at the transition state lags behind bond changes, increases the intrinsic barrier of a reaction, but lowers it if it develops ahead of bond changes. Because of the generality of this principle, details of transition state structures can be deduced from comparisons of intrinsic barriers within classes of reactions. A major conclusion that has emerged from such comparisons is that reactions that lead to charge delocalization/resonance stabilized products have transition states in which the development of charge delocalization/resonance stabilization lags behind bond changes and, hence, have relatively high intrinsic barriers. This paper deals with reactions that lead to aromatic molecules or ions. The question we are asking is whether or not aromaticity follows the pattern of common resonance effects and lags behind bond changes at the transition state. Evidence based on experimentally determined intrinsic barriers of proton transfers from rhenium carbene complexes in solution, as well as that based on ab initio calculations of proton transfers in the gas phase, suggests that aromaticity development at the transition state may actually be ahead of bond changes. Copyright © 2004 John Wiley & Sons, Ltd.
Role of cyclic dithiocarbonate as a promoter in the reaction of epoxide and imine in the presence of water
Authors: Suzuki Kentarou , Horii Hisakazu , Sugita Yuko , Sanda Fumio , Endo Takeshi 
Published: July 2004

AbstractIt was demonstrated that the reaction of epoxide and imine as a latent initiator under highly humid conditions was accelerated by addition of 5‐phenoxymethyl‐1,3‐oxathiolane‐2‐thione (1). When 1 was added to a mixture of glycidyl phenyl ether and an imine, the reaction of the epoxide with an amine released from the imine became faster than was the case without 1, that is, 1 worked as a promoter of the reaction. The curing rate and initial adhesive strength of epoxy resin increased compared with that without 1. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4276–4283, 2004
Konjac glucomannan‐graft‐acrylic acid hydrogels containing azo crosslinker for colon‐specific delivery
Authors: Liu Zhi‐Lan , Hu Han , Zhuo Ren‐Xi 
Published: July 2004

AbstractIn this article, the synthesis and characterization of novel hydrogel systems designed for colon‐targeting drug delivery are reported. The gels were composed of konjac glucomannan, copolymerized with acrylic acid, and crosslinked by the aromatic azo agent bis(methacryloylamino)‐azobenzene. The influence of various parameters on the dynamic and equilibrium swelling ratios (SRs) of the hydrogels was investigated. It is shown that the SR was inversely proportional to the grafting degree of acrylic acid and the content of bis(methacryloylamino)‐azobenzene. The dependence of SR on the pH indicates that obtained hydrogels are potential for drug delivery to colon. It was possible to modulate the degree of swelling and the pH sensitivity of the gels by changing crosslinking density of the polymer. The main chain of hydrogels can be degraded by β‐glycosidase which is abundant in colon. They can be in vitro degraded for 73% in a month by Cereflo® and 86% in 20 days by Mannaway25L. We have also prepared the hydrogels that loaded with bovine serum albumin about 1.5%, 3%, 9%, and 20% by weight. In vitro release of model drug bovine serum albumin was studied in the presence of Mannaway25L or Fungamyl®800L in pH 7.4 phosphate buffer at 37 °C. The drug release can be controlled by the biodegradation of the hydrogels. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4370–4378, 2004
Gel‐like aspect of a miscible polymer mixture studied by small‐angle neutron scattering
Authors: Koizumi Satoshi 
Published: July 2004

AbstractBy employing small‐angle neutron scattering (SANS), we have investigated a miscible mixture of polystyrene (PS) and poly(vinyl methyl ether) (PVME) to answer the question of what a gel state is. The large difference in the glass‐transition temperatures (Tg's) of PS and PVME uniquely enhances dynamic asymmetry by a temperature change. In an intermediate temperature range between the two Tg's, SANS reveals two interesting findings: (1) the anomalous suppression of small‐angle scattering in a quiescent state and (2) an abnormal butterfly scattering pattern due to shear‐induced phase separation. In this temperature region, we have further confirmed experimentally that the mixture behaves in a gel‐like limit at which concentration fluctuations relax more quickly than rheological relaxation. With the gel‐like limit and enhanced dynamic asymmetry, which is required for the gel state, our two SANS findings can be interpreted within the theoretical framework of dynamical coupling between stress and diffusion. For comparison, we have studied a swollen real chemical gel of poly(N‐isopropyl acrylamide), in which covalent bonds crosslink chains heterogeneously. A combined method of SANS and neutron spin echo has been used to quantitatively determine the static inhomogeneity, which gives rise to a structure factor of a squared Lorentzian shape. The static inhomogeneity is closely related to the nonergodic feature of excess scattering when the gel is subjected to swelling or nondecaying abnormal butterfly scattering under deformation. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3148–3164, 2004
Time‐resolved small‐angle neutron scattering study of polyethylene crystallization from solution
Authors: Wang Howard 
Published: July 2004

AbstractWith time‐resolved small‐angle neutron scattering (TR‐SANS), the crystallization kinetics of polyethylene from deuterated o‐xylene solutions upon a temperature jump have been investigated. On the basis of a morphological model of coexisting lamellar stacks and coil chains in solution, experimental data have been quantitatively analyzed to provide structural information, such as the lamellar long period, the lamellar crystal thickness, the thickness of the amorphous layers between lamellae, the degree of crystallinity, and the crystal growth rate at various degrees of undercooling. The viability of TR‐SANS for studying polymer crystallization is demonstrated through the consistency of these measurements and well‐established knowledge of polyethylene crystallization from xylene solutions. One unique feature of this experimentation is that both the growth of lamellar crystals and the condensation of coil chains from solution are monitored simultaneously. The ratio of the crystal growth to the chain consumption rate decreases rapidly with a decreasing degree of undercooling. The Avrami analysis suggests that the growth mechanism approaches two‐dimensional behavior at higher temperatures, and this is consistent with the observation of an increasing ratio of the sharp‐surface area to the bulk crystal growth rate with temperature. The limitations, possible remedies, and potentials of TR‐SANS for studying polymer crystallization are discussed. © 2004 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 42: 3133–3147, 2004
Quality of life and psychological adaptation in siblings of paediatric cancer patients, 2 years after diagnosis
Authors: Houtzager B.A. , Grootenhuis M.A. , Caron H.N. , Last B.F. 
Published: July 2004

AbstractSeveral studies have been conducted on sibling psychosocial adaptation to cancer in a brother or sister, but little is known on how the long‐term adaptation of siblings to the illness develops. The concept quality of life has primarily been applied in research on the effects of chronic illness on the affected patient, but has not yet been studied in siblings. Aims: To investigate the prevalence of self‐reported psychosocial problems in siblings of pediatric cancer patients, 2 years after the onset of the illness. Measurements: Two Dutch quality of life questionnaires, the TACQOL and the DUCATQOL are used, as well as generic non‐health‐related measures of emotional and behaviour problems (CBCL‐YSR) and anxiety (STAI‐C). Participants: Participants were 103 siblings aged 7–18 years old. Fifty seven Siblings participated in a prospective and 46 in a retrospective study group. Results: Siblings aged 7–11 report lower overall quality of life than children in the norm group. No differences in mean scores were found on any of the other domains that were investigated. When the prevalence of problems was investigated, however, relatively more siblings compared to normative data had scores in the impaired group based on the 20th percentile norm. A relatively high number of siblings aged 7–11 reported impaired emotional (42%), social (34%) and total quality of life (47%) (DUCATQOL) and physical problems (26%) (TACQOL). Relatively many adolescent siblings (26%) reported significant internalising problems on the CBCL‐YSR. Conclusions: Although acute emotional distress reactions seem to have normalised in most siblings as has been suggested in the literature, emotional distress of having a brother or sister with cancer may continue beyond diagnosis for a subgroup of children. Young siblings seem to be affected in their quality of life, whereas a subgroup of adolescent siblings experience clinically relevant internalising problems. The results support the use of quality of life measures for siblings. Predictors of long‐term adaptation in siblings need to be investigated. Copyright © 2003 John Wiley & Sons, Ltd.
Parent‐reported environmental tobacco smoke exposure among preadolescents and adolescents treated for cancer
Authors: Tyc Vida L. , Klosky James , Throckmorton‐Belzer Leslee , Lensing Shelly , Rai Shesh N. 
Published: July 2004

AbstractExposure to environmental tobacco smoke (ETS) poses serious health risks for children with cancer. Parental smoke is a primary source of exposure for these children. Parent smoking behaviors and parent‐reported ETS exposure among children treated for cancer were examined in this study. In addition, reports of ETS exposure among children with cancer who currently smoked or who had smoked in the past were compared to those of children with cancer who never smoked. Written questionnaires about smoking behaviors and ETS exposure were administered to 47 smoking parents of youngsters diagnosed with cancer, 10–18 years of age (57.4% male, 78.7% Caucasian). Child reports of smoking status were also obtained. Results indicated that children with cancer are exposed to ETS from a number of sources and settings, as reported by their parents. Current or previous child smokers had greater ETS exposure than non‐smoking children. Older children and Caucasian children also had greater ETS exposure. Level of ETS exposure did not differ based on the child's treatment status. Interventions that teach parents to protect their youngster from ETS exposure have potential for reducing adverse health outcomes in this vulnerable population. Copyright © 2003 John Wiley & Sons, Ltd.
The psychological impact of a cancer diagnosis on families: The influence of family functioning and patients' illness characteristics on depression and anxiety
Authors: Edwards Ben , Clarke Valerie 
Published: July 2004

AbstractA diagnosis of cancer is a very stressful event for the patients and their families. Patients, partners and other family members can suffer from clinical levels of depression and severe levels of anxiety and stress reactions. The similarity in levels of distress between patients and partners and patients and offspring suggests that there are common factors that impact on families' distress levels. The current study examined levels of depression and anxiety in newly diagnosed adult patients (n=48) and their adult relatives (n=99). Family functioning and patients' illness characteristics were identified as factors that might impact on families' depression and anxiety. Results from multilevel models indicated that family functioning was important. Families that were able to act openly, express feelings directly, and solve problems effectively had lower levels of depression. Direct communication of information within the family was associated with lower levels of anxiety. Aside from differences anxiety due to cancer type, patients' illness characteristics appear to be risk factors in patients' but not relatives' depression and anxiety. The results from the current study suggest that researchers and clinicians need to be family‐focused as cancer affects the whole family, not just the patient. Copyright © 2003 John Wiley & Sons, Ltd.
Ranking the risk of pesticide dietary intake
Authors: Low Felicia , Lin Hui‐Ming , Gerrard Juliet A , Cressey Peter J , Shaw Ian C 
Published: July 2004

AbstractPesticide residues in various foods were assessed for the relative risk to the consumer. The analysis took into account criteria such as a pesticide's toxicity, usage, frequency of occurrence in foods, frequency of Maximum Residue Level (MRL) exceedances, and the overall risks of specific pesticide/food combinations. Examination of the top ten ranked pesticides for each criterion showed that there are no trends of commonality. Thus, no single pesticide is of particular concern from a consumer's point of view. This suggests that the consumer's risk perception is likely to be higher than justified. Copyright © 2004 Society of Chemical Industry
Nonlinear Seebeck and Peltier effects in quantum point contacts
Authors: Çipiloğlu M. A. , Turgut S. , Tomak M. 
Published: July 2004

AbstractThe charge and entropy currents across a quantum point contact are expanded as a series in powers of the applied bias voltage and the temperature difference. After that, the expansions of the Seebeck voltage in temperature difference and the Peltier heat in current are obtained. With a suitable choice of the average temperature and chemical potential, the lowest order nonlinear term in both cases appear to be of third order. The behavior of the third‐order coefficients in both cases are then investigated for different contact parameters. (© 2004 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Stereospeciﬁc effects of catechin isomers on insulin induced lipogenesis in 3T3‐L1 cells
Authors: Mochizuki Miyako , Hasegawa Noboru 
Published: July 2004

AbstractWe studied the inﬂuence of (+)‐ and (−)‐catechin contained in green tea on insulin induced lipogenesis in 3T3‐L1 cells. In 14 days of culture with insulin, the intracellular triglyceride concentration and the activities of glycerophosphate dehydrogenase, a marker of adipose conversion, increased. The addition of 0.02 mg/ml (+)‐isomer stimulated the accumulation of triglyceride induced by insulin, but the addition of the same concentration of (−)‐isomer inhibited lipogenesis. The activities of glycerophosphate dehydrogenase were changed by (+)‐ and (−)‐catechin in the same direction as the corresponding changes in triglyceride accumulation. These data suggest a biological signiﬁcance of catechins, with opposite effects on lipid metabolism depending on the isomer. Copyright © 2004 John Wiley & Sons, Ltd.
Inhibitory effects of leaf extracts of Stachytarpheta jamaicensis (Verbenaceae) on the respiratory burst of rat macrophages
Authors: Álvarez Ezequiel , Leiro José Manuel , Rodríguez Melita , Orallo Francisco 
Published: July 2004

AbstractThe anti‐oxidant effects of ethyl acetate (EAcE) and n‐hexane extracts (nHE) of dried leaves of Stachytarpheta jamaicensis Vahl. (Verbenaceae) on the reactive oxygen species (ROS) generating during the respiratory burst of rat peritoneal macrophages were investigated. Only EAcE, at concentrations between 0.4 and 40 µg/ml, inhibited the extracellular release of oxygen radicals by resident peritoneal macrophages stimulated with phorbol‐12‐myristate 13‐acetate (PMA). At concentrations above 40 µg/ml, EAcE inhibited the production of nitric oxide (NO) in macrophages stimulated in vivo with sodium thioglycollate then in vitro with lipopolysaccharide (LPS) and gamma‐interferon (IFN‐γ). nHE extracts at concentrations between 0.4 and 40 µg/ml did not scavenge O−2 generated enzymatically by hypoxanthine/xanthine oxidase (HX/XO) system, but EAcE at the same concentrations showed potent O−2‐scavenging activity. At 40 µg/ml, EAcE also inhibited XO activity. These results suggest that the EAcE extract of S. jamaicensis may be a potential pharmaceutical value in treatment of immunopathological diseases related to oxidative stress. Copyright © 2004 John Wiley & Sons, Ltd.