bluuebunny/crossref_metadata_2025_split huggingface dataset:
Localization of white matter volume increase in autism and developmental language disorder
Authors: Herbert Martha R. , Ziegler David A. , Makris Nikos , Filipek Pauline A. , Kemper Thomas L. , Normandin Joseph J. , Sanders Heather A. , Kennedy David N. , Caviness Verne S. 
Published: March 2004

AbstractIncreased brain volume in autism appears to be driven mainly by an unexplained white matter enlargement, and we have reported a similar phenomenon in developmental language disorder (DLD). Localization of this enlargement would strongly guide research into its cause, tissue basis, and functional implications. We utilized a white matter parcellation technique that divides cerebral white matter into an outer zone containing the radiate compartment and an inner zone containing sagittal and bridging system compartments. In both high‐functioning autism and DLD, enlargement localized to the radiate white matter (all lobes in autism, all but parietal in DLD), whereas inner zone white matter compartments showed no volume differences from controls. Furthermore, in both autism and DLD, later or longer‐myelinating regions showed greater volume increases over controls. Neither group showed cerebral cortex, corpus callosum, or internal capsule volume differences from control. Radiate white matter myelinates later than deep white matter; this pattern of enlargement thus is consistent with striking postnatal head circumference percentile increases reported in autism. These findings suggest an ongoing postnatal process in both autism and DLD that is probably intrinsic to white matter, that primarily affects intrahemispheric and corticocortical connections, and that places these two disorders on the same spectrum.
Glutamate receptor antagonists protect from virus‐induced neural degeneration
Authors: Nargi‐Aizenman Jennifer L. , Havert Michael B. , Zhang Ming , Irani David N. , Rothstein Jeffrey D. , Griffin Diane E. 
Published: March 2004

AbstractNeuronal damage during acute viral encephalomyelitis can result directly from virus infection or indirectly from the host immune response to infection. In neurodegenerative diseases and stroke, neuronal death also can result from excess release of excitatory amino acid neurotransmitters, such as glutamate. To determine the role of glutamate excitotoxicity in fatal alphavirus‐induced paralytic encephalomyelitis, we treated mice infected with neuroadapted Sindbis virus (NSV) with antagonists of N‐methyl‐D‐aspartate (NMDA) and α‐amino‐3‐hydroxy‐5‐methyl‐4‐isoxazole propionic acid (AMPA) subtypes of glutamate receptors. Both apoptotic and necrotic neurons in the hippocampus were decreased in animals treated with MK‐801, an NMDA receptor antagonist, or GYKI‐52466, an AMPA receptor antagonist. However, only AMPA receptor blockade prevented damage to spinal cord motor neurons and protected mice from paralysis and death due to NSV infection. Protection was not caused by altered virus replication because treatment did not affect virus distribution and actually delayed virus clearance. These results provide evidence that NSV infection activates neurotoxic pathways that result in aberrant glutamate receptor stimulation and neuronal damage. Furthermore, AMPA receptor–mediated motor neuron death is an important contributor to paralysis and mortality in acute alphavirus‐induced encephalomyelitis.
Paroxetine retards disease onset and progression in Huntingtin mutant mice
Authors: Duan Wenzhen , Guo Zhihong , Jiang Haiyang , Ladenheim Bruce , Xu Xiangru , Cadet Jean Lud , Mattson Mark P. 
Published: March 2004

AbstractWe report that administration of paroxetine, a widely prescribed antidepressant drug that acts by inhibiting reuptake of the neurotransmitter serotonin, suppresses the neurodegenerative process and increases the survival of huntingtin mutant mice, an animal model of Huntington's disease (HD). Paroxetine attenuated motor dysfunction and body weight loss and improved glucose metabolism in the HD mice. Paroxetine was beneficial when treatment was initiated before or after the onset of motor dysfunction, suggesting a potential for such antidepressant drugs in the treatment of presymptomatic and symptomatic HD patients.
Study of cationic ring‐opening photopolymerizations using optical pyrometry
Authors: Crivello J. V. , Falk B. , Zonca M. R. 
Published: March 2004

AbstractStudies of the photoinitiated cationic ring‐opening polymerizations of epoxide and oxetane monomers were conducted using optical pyrometry. Using this technique, the temperature of these photopolymerizations was monitored as a function of time. The effects of photoinitiator type and monomer structure on the rates of photopolymerization were investigated. Optical pyrometry was also used to investigate the acceleration of the photopolymerizations of various epoxide and oxetane monomers. Certain mixtures of monomers displayed synergistic effects that markedly increased their overall rates of polymerizations. In all cases in which acceleration of polymerization rate was noted, it could be attributed to an increase in the speed of ring opening of the initially formed protonated cyclic ether. The effects of relative humidity on the rate of cationic ring‐opening photopolymerizations of cyclic ether monomers were also investigated. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3303–3319, 2004
Modeling the curing kinetics for a modified bismaleimide resin using isothermal DSC
Authors: Guo Zhan‐Sheng , Du Shan‐Yi , Zhang Bo‐Ming , Wu Zhan‐Jun 
Published: March 2004

AbstractThe kinetics of curing for a modified bismaleimide (BMI) resin was investigated to ascertain a suitable cure model for the material. The resin system used in this study was composed of 4,4′‐bismaleimidodiphenylmethane (BMIM) and 0,0′‐diallyl bisphenol A (DABPA, DABA). The BMIM was the base monomer and the DABPA was the modified agent. A series of isothermal DSC runs provided information about the kinetics of cure in the temperature range 170–220°C. Regardless of the different temperatures, the shape of the conversion curves was similar, and this modified BMI resin system underwent an nth‐order cure reaction. Kinetic parameters of this BMI resin system, including the reaction model, activation energy, and frequency factor, were calculated. From the experimental data, it was found that the cure kinetics of this resin system can be characterized by a first‐order kinetic model. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3338–3342, 2004
Effect of an obstacle during processing on the weld line of injection‐molded glassy polystyrene: Microhardness study
Authors: Nguyen‐Chung T. , Mennig G. , Boyanova M. , Fakirov S. , Baltá Calleja F. J. 
Published: March 2004

AbstractThe microhardness (H) technique is used to characterize the quality of the weld line in injection‐molded glassy polystyrene by means of a cylindrical obstacle. In particular, the effect of the indentation location (closer or further from the obstacle edge parallel to the injection direction and across the weld line), both on the surface and in the bulk, was examined. Only for surface measurements close to the obstacle (up to 10 mm) a well‐pronounced decrease in H (∼30%), followed by a sharp increase in a narrow distance (0.20–0.25 mm), was observed. For the bulk measurements on the same location a slight decrease in H was detected. Additional H measurements made up to 60 mm from the obstacle for both cases showed that the weld line remains undetectable. The results obtained reveal that the presence of a cylindrical obstacle causes the formation of a weld line on and near the surface only at distances not exceeding the obstacle diameter. At larger distances, because of the effective mutual interdiffusion of polymer chains, the two parallel fronts coming from the two sides of the obstacle developed a homogeneous material without any weld line according to the microhardness test. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3362–3367, 2004
Dynamic mechanical and Raman spectroscopy studies on interaction between single‐walled carbon nanotubes and natural rubber
Authors: López‐Manchado M. A. , Biagiotti J. , Valentini L. , Kenny J. M. 
Published: March 2004

AbstractThe effects of the incorporation of single‐walled carbon nanotubes (SWNTs) on the physical and mechanical properties of natural rubber (NR) are described. Characterization of these new materials has been performed by dynamic mechanical analysis, differential scanning calorimetry, and Raman spectroscopy to obtain information about of the possible interactions between both materials as well as the dispersion of SWNTs on elastomer matrix. The results are then compared with those obtained for NR–carbon black composites. Dynamic mechanical analysis indicates a stronger filler–matrix interaction in the case of SWNTs incorporation, showing a noticeable decrease of the height of tan δ peak, as well as a marked shift of Tg towards higher temperatures. In particular, the increase of the storage modulus indicates a beneficial effect of SWNTs incorporation with respect to NR filled with carbon black and the pristine polymer matrix. In addition, calorimetric analysis indicates that both fillers accelerate the NR vulcanization reaction, this effect being more evident when SWNTs are added into the matrix. Raman spectroscopy indicates that SWNTs dispersion into the elastomer matrix creates residual strain on the nanotubes bundle. We demonstrate that the Raman microprobe technique provides a means for load transfer effectiveness of SWNTs. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3394–3400, 2004
Eucalyptus bark lignin substituted phenol formaldehyde adhesives: A study on optimization of reaction parameters and characterization
Authors: Khan Mozaffar Alam , Ashraf Sayed Marghoob , Malhotra Ved Prakash 
Published: March 2004

AbstractThe major adhesive resin worldwide used in the manufacture of plywood is phenol formaldehyde resole (PF) resin. The raw material for this kind of adhesive is derived from petroleum oil. Because of rising prices of crude oil and the scarcity of petroleum products, their replacement by natural resource–based raw material has become a necessity. In the present work, the possibility of replacing phenol in PF resin with lignin was explored. The parameters for preparation of bark lignin substituted PF (LPF) adhesive, such as lignin concentration, formaldehyde to phenol molar ratio, catalyst concentration, reaction time, and reaction temperature, were optimized. It was found that up to 50 wt % of phenol can be substituted by lignin to give an LPF adhesive with better bonding strength compared to that of control PF resin. Prepared resins were characterized using IR, DSC, and TGA. IR spectra of LPF adhesive showed structural similarity with that of PF adhesives. Thermal stability of LPF adhesive was found to be lower compared to that of control PF (CPF) adhesive. DSC studies revealed a lower curing temperature for LPF resin than that for CPF resin. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3514–3523, 2004
Recovery in spider silk fibers
Authors: Elices M. , Pérez‐Rigueiro J. , Plaza G. , Guinea G. V. 
Published: March 2004

AbstractThe extreme toughness of spider silk is dependent on the silk's ability to dissipate most of the mechanical energy imparted to the fiber during loading processes through irreversible deformations. This basic property makes the tensile behavior of spider silk fibers depend on the silk's previous deformation history in a largely unpredictable way. The resulting variability often represents an insurmountable difficulty for both the characterization of the material and its practical usage. In this study, it was shown that spider silk is endowed with a property that allows to circumvent these problems: supercontraction, the large shrinkage of the longitudinal dimension of spider silk fibers in wet environments, recovers the tensile properties of deformed spider silk fibers in a repetitive and reproducible way. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3537–3541, 2004
Effects of aluminum alkyls on ethylene/1‐hexene polymerization with supported metallocene/MAO catalysts in the gas phase
Authors: Hammawa H. , Mannan T. M. , Lynch D. T. , Wanke S. E. 
Published: March 2004

AbstractThe effects of aluminum alkyls on the gas‐phase ethylene homopolymerization and ethylene/1‐hexene copolymerization over polymer‐supported metallocene/methylaluminoxane [(n‐BuCp)2ZrCl2/MAO] catalysts were investigated. Results with triisobutyl aluminum (TIBA), triethyl aluminum (TEA), and tri‐n‐octyl aluminum (TNOA) showed that both the type and the amount of aluminum alkyl influenced the polymerization activity profiles and to a lesser extent the polymer molar masses. The response to aluminum alkyls depended on the morphology and the Al : Zr ratio of the catalyst. Addition of TIBA and TEA to supported catalysts with Al : Zr >200 reduced the initial activity but at times resulted in higher average activities due to broadening of the kinetic profiles, i.e., alkyls can be used to control the shape of the activity profiles. A catalyst with Al : Zr = 110 exhibited relatively low activity when the amount of TIBA added was <0.4 mmol, but the activity increased fivefold by increasing the TIBA amount to 0.6 mmol. The effectiveness of the aluminum alkyls in inhibiting the initial polymerization activity is in the following order: TEA > TIBA >> TNOA. A 2‐L semibatch reactor, typically run at 80°C and 1.4 MPa ethylene pressure for 1 to 5 h was used for the gas‐phase polymerization. © 2004 Wiley Periodicals, Inc. J Appl Polym Sci 92: 3549–3560, 2004
Query association surrogates for Web search
Authors: Scholer Falk , Williams Hugh E. , Turpin Andrew 
Published: March 2004

AbstractCollection sizes, query rates, and the number of users of Web search engines are increasing. Therefore, there is continued demand for innovation in providing search services that meet user information needs. In this article, we propose new techniques to add additional terms to documents with the goal of providing more accurate searches. Our techniques are based on query association, where queries are stored with documents that are highly similar statistically. We show that adding query associations to documents improves the accuracy of Web topic finding searches by up to 7%, and provides an excellent complement to existing supplement techniques for site finding. We conclude that using document surrogates derived from query association is a valuable new technique for accurate Web searching.
Toward wellness: Women seeking health information
Authors: Warner Dorothy , Procaccino J. Drew 
Published: March 2004

AbstractAs health information seekers pursue their “right to know” when investigating medical options, the question of reliable health information resources becomes paramount. Previous research has not addressed widely the connection between women as the health information seeker and quality health information, nor has women's awareness of specific health and medical resources been adequately evaluated. A study with a convenience sample of 119 women assessed the process of seeking health information (women's health information needs, the search strategies they employed for filling the information need, and the use of the health information found), and their awareness of specific health and medical information resources. Our survey instrument was based on Kuhlthau's Information Search Process (ISP) model. Results appeared to address the uncertainty stage of the ISP model, as there were conflicting responses regarding the facility of locating information, the usefulness of the information found, and whether or not the subjects' health questions were answered. The study also identified a low awareness by our respondents of specific health and medical information resources. There is an opportunity for health information providers to play a role in mediating at this uncertainty stage to connect health information seekers with reliable information.
Use of the World Wide Web for international travel: Integrating the construct of uncertainty in information seeking and the task‐technology fit (TTF) model
Authors: D'Ambra John , Wilson Concepción S. 
Published: March 2004

AbstractIn this study, we attempt to evaluate the performance of the World Wide Web as an information resource in the domain of international travel. The theoretical framework underpinning our approach recognizes the contribution of models of information seeking behavior and of information systems in explaining World Wide Web usage as an information resource. Specifically, a model integrating the construct of uncertainty in information seeking and the task‐technology fit model is presented. To test the integrated model, 217 travelers participated in a questionnaire‐based empirical study. Our results confirm that richer (or enhanced) models are required to evaluate the broad context of World Wide Web (the Web) usage as an information resource. Use of the Web for travel tasks, for uncertainty reduction, as an information resource, and for mediation all have a significant impact on users' perception of performance, explaining 46% of the variance. Additionally, our study contributes to the testing and validation of metrics for use of the Web as an information resource in a specific domain.
Modeling cognitive processes in information seeking: From Popper to Pask
Authors: Ford Nigel 
Published: March 2004

AbstractThis report explores the intellectual processes entailed during information seeking, as information needs are generated and information is sought and evaluated for relevance. It focuses on the details of cognitive processing, reviewing a number of models. In particular, Popper's model of the communication process between an individual and new information is explored and elaborated from the perspective of Pask'sConversation Theory. The implications of this theory are discussed in relation to the development of what Cole has termed “enabling” information retrieval systems.
Seeking information in order to produce information: An empirical study at Hewlett Packard Labs
Authors: Hirsh Sandra , Dinkelacker Jamie 
Published: March 2004

AbstractThe essential characteristic of knowledge workers is that they use information to produce information subsequently. Hence, information seeking is a knowledge worker's central aspect of work life. In a corporate research laboratory environment, this is even more pronounced because the results produced are often in the form of more information, such as publications, tech reports, patent applications, or the embodiment of these into prototypes. The practices and expectations regarding information seeking and collaboration are fundamental to productive research in a corporate setting. To this end, a survey research project sampled researchers from selected labs of Hewlett Packard and Compaq Computer shortly after their merger. This survey examined researchers' usage of information sources, their preferred means of information seeking, and the types of information assets they produced. Findings indicated that participants relied heavily on the Internet and other Web‐based resources, more so than on their colleagues inside the company. Participants chose which information resources to use based on the time it took them to track down the information as well as the authoritativeness of the sources. Most information assets were generated collaboratively by teams rather then by individuals. Findings suggested that behavior was affected by the unstable environment resulting from the merger and the process of integrating the two research organizations.
Pharmacokinetic changes of DA‐8159, a new erectogenic, after intravenous and oral administration to rats with acute renal failure induced by uranyl nitrate
Authors: Shim Hyun J. , Kim Yu C. , Kim Eun J. , Kim Dong G. , Kwon Jong W. , Kim Won B. , Lee Myung G. 
Published: March 2004

AbstractThe pharmacokinetic parameters of DA‐8159, a new erectogenic, were compared after intravenous and oral administration of the drug at a dose of 30 mg/kg to control rats and rats with acute renal failure induced by uranyl nitrate (U‐ARF). After intravenous administration to rats with U‐ARF, the plasma concentrations of DA‐8159 were higher than those in control rats. This resulted in a significantly greater area under the plasma concentration–time curve from time zero to time infinity (AUC) of DA‐8159 in rats with U‐ARF (304 compared with 365 μg min/ml for control rats and rats with U‐ARF). The significantly greater AUC in rats with U‐ARF was due to significantly slower total body clearance (Cl) of DA‐8159 (98.6 compared with 82.2 ml/min/kg). The significantly slower Cl in rats with U‐ARF was due to slower renal clearance (1.07 ml/min/kg compared with not calculable, due to impaired kidney function) and nonrenal clearance (97.5 compared with 82.2 ml/min/kg due to slower metabolism) than those in control rats. After oral administration of DA‐8159 to rats with U‐ARF, the AUC (122 compared with 172 μg min/ml) was significantly greater and ClR was slower (3.47 ml/min/kg compared with not calculable) than those in control rats. The significantly greater AUC in rats with U‐ARF could be due to slower Cl of DA‐8159 in the rats. Copyright © 2004 John Wiley & Sons, Ltd.
Dose‐dependent pharmacokinetics of KR‐31378, a new neuroprotective agent for ischaemia‐reperfusion damage in dogs
Authors: Kim Sun‐O. , Kwak Sang‐H. , Lee Byung H. , Lee Dong‐H. , Lim Hong , Yoo Sung‐E. , Chung Hye J. , Lee Myung G. 
Published: March 2004

AbstractDose‐dependent pharmacokinetic parameters of KR‐31378, a new neuroprotective agent for ischaemia‐reperfusion damage, were evaluated after intravenous and oral administration of the drug at doses of 5, 10 and 25 mg/kg to male beagle dogs. After intravenous administration, the dose‐normalized (based on 5 mg/kg) areas under the plasma concentration−time curve from time zero to time infinity (AUC values, 725, 1450 and 2300 µg min/ml for 5, 10 and 25 mg/kg, respectively) were significantly different among the three dose ranges studied; the value increased more proportionally as the dose increased. This could be due to slower total body clearance (Cl) with increasing doses (6.90, 3.46 and 2.17 ml/min/kg). The slower Cl value with increasing doses may be due to saturable metabolism of KR‐31378 in dogs. After oral administration, the dose‐normalized (based on 5 mg/kg) AUC values (833, 1450 and 1920 µg min/ml) at 5 mg/kg were significantly smaller than those at 10 and 25 mg/kg. Note that the AUC values were comparable (not significantly different) between intravenous and oral administration at all doses studied, indicating that the absorption of KR‐31378 from the gastrointestinal tract was essentially complete and the first‐pass (gastric, intestinal and/or hepatic first‐pass) effects were almost negligible in dogs. Copyright © 2004 John Wiley & Sons, Ltd.