bluuebunny/crossref_metadata_2025_split huggingface dataset:
Two‐sided comb poly(amic ester)–poly(propylene oxide) graft copolymers as porous polyimide precursors
Authors: Lebedeva Elena , Kesler Brenda S. , Carter Kenneth R. 
Published: April 2005

AbstractNew step‐growth graft block copolymers were synthesized. These two‐sided comb copolymers consisted of a poly(amic ester) (PAE) backbone and pendant poly(propylene oxide) (PPO) grafts. The copolymers were made via a macromonomer approach, in which the 4,6‐bischlorocarbonyl isophthalic acid bis[poly(propylene oxide)] ester macromonomer was synthesized through the reaction of hydroxyl‐terminated PPO oligomers with pyromellitic dianhydride and oxalyl chloride. This macromonomer was subsequently used in step‐growth polymerization with comonomers 4,6‐bischlorocarbonyl isophthalic acid diethyl ester, 2,5‐bischlorocarbonyl terephthalic acid diethyl ester, and 2,2‐bis[4‐ (4‐aminophenoxy)phenyl] hexafluoropropane, and this yielded PPO‐co‐PAE graft copolymers. Accordingly, we report the synthesis and characterization of the PPO oligomer, the PPO macromonomer, and their corresponding PPO‐co‐PAE graft copolymers. Graft copolymers with PPO concentrations of 3–26 wt % were synthesized. These polymers were thermally cured to produce polyimide/PPO composites. The thermolysis of these polyimide/PPO composites yielded porous polyimide films with porosities ranging of 4–22.5%. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2266–2275, 2005
Multiple morphologies from a novel diblock copolymer containing dendronized polymethacrylate and linear poly(ethylene oxide)
Authors: Cheng Cai‐Xia , Tang Ru‐Pei , Xi Fu 
Published: April 2005

AbstractA novel amphiphilic diblock copolymer, consisting of dendronized polymethacrylate‐b‐poly(ethylene oxide), was synthesized via atom transfer radical polymerization; from it, micellelike aggregates of various morphologies, prepared under near‐equilibrium conditions, were studied with transmission electron microscopy and scanning electron microscopy. The effects of various factors on the aggregate morphologies of the amphiphilic copolymer, such as the water content, the copolymer concentration, and the type of common solvent, were investigated systematically. The unique architecture of the block copolymer led to morphological variety and peculiarities such as dendritic and shuttle‐shaped aggregates, which could be attributed to the effective packing of the bulky side chains, that is, another driving force for the aggregates. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2291–2297, 2005
Kinetic behavior of ethylene/1‐hexene copolymerization in slurry and solution reactors
Authors: Wu Long , Bu Naiyu , Wanke Sieghard E. 
Published: April 2005

AbstractThe copolymerization of ethylene and 1‐hexene over a spherical polymer/MgCl2‐supported TiCl4 catalyst was studied as a function of the polymerization temperature from 40 to 100 °C in a slurry reactor and from 120 to 200 °C in a solution reactor with triethylaluminum (TEA) as a cocatalyst (1.0–6.8 mmol). The activities increased from 40 to 80 °C and then declined monotonically with increases in the temperature during the slurry and solution polymerizations. The kinetic behavior in the slurry and solution operations was described by the same rate expression. The modeling results indicated that the catalyst had at least two different types of catalytic sites; one site was responsible for the acceleration–decay nature of the activity profiles, whereas the second site resulted in long‐term activity. The apparent activation energy for site activation in the slurry operation was 69.9 kJ/mol; no activation energies for site activation could be estimated for the solution operation because the activation process was essentially instantaneous at the higher temperatures. The activation energies for deactivation were 100.3 kJ/mol for the slurry operation and 31.2 kJ/mol for the solution operation. The responses to TEA were similar for the slurry and solution operations; the rates increased with increasing amounts of TEA between 1.0 and 3.4 mmol and then decreased with larger amounts of TEA. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2248–2257, 2005
Synthesis and curing of poly(glycidyl methacrylate) nanoparticles
Authors: Jang Jyongsik , Bae Joonwon , Ko Sungrok 
Published: April 2005

AbstractGlycidyl‐functional polymer nanoparticles [poly(glycidyl methacrylate) (PGMA)] were fabricated with microemulsion polymerization. The successful fabrication of PGMA nanoparticles was confirmed by Fourier transform infrared spectroscopy and transmission electron microscopy (TEM). A TEM image showed that the average diameter of the PGMA nanoparticles was approximately 10–28 nm and was fairly monodisperse. As the surfactant concentration increased, the average size of the nanoparticles decreased and approached an asymptotic value. A significant reduction of the nanoparticle size to the nanometer scale led to an enhanced number of surface functionalities, which played an important role in the curing reaction. The PGMA nanoparticles were cured with a low‐temperature curing agent, diethylene triamine, to produce ultrafine thermoset nanoparticles. The low‐temperature curing process was performed below the glass‐transition temperature of PGMA to prevent the coagulation and deformation of the nanoparticles. A TEM image indicated that the cured PGMA nanoparticles did not exhibit interparticle aggregation and morphological transformation during curing. The average size of the cured PGMA nanoparticles was consistent with that of the pristine PGMA nanoparticles © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2258–2265, 2005
Calculated infrared spectra of hydrogen‐bonded methanol–water, water–methanol, and methanol–methanol complexes
Authors: Fileti Eudes E. , Canuto Sylvio 
Published: April 2005

AbstractAb initio calculations at the B3LYP/aug‐cc‐pVDZ, B3PW91/aug‐cc‐pVDZ, MP2/aug‐cc‐pVDZ, B3LYP/6‐311++G(2d,2p), B3PW91/6‐311++G(2d,2p), and MP2/6‐311++G(2d,2p) levels are performed for the IR spectra of isolated water and methanol molecules and hydrogen‐bonded water–methanol, methanol–water, and methanol–methanol complexes. Frequency shifts and changes in intensities are obtained for the proton donor molecule and the results are compared with available experimental and theoretical results. Characteristic changes are discussed in all cases. For methanol we obtained considerable shifts in the OH group. The COH wag is calculated to blue shift and the OH stretch is calculated to red shift and increase in intensity is compared to the isolated methanol molecule. The magnitude of these shifts are obtained and discussed. For the methanol dimer the COH wag increases the frequency by ∼400 cm−1and the OH stretch decreases the frequency by ∼170 cm−1, with an increase in intensity of nearly 15 times. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Asymmetric structure for the excited S1 state of 2,2′‐bipyridine evidenced by picosecond time‐resolved resonance raman experiments and ab initio calculation
Authors: De Waele V. , Buntinx G. , Flament J‐P. , Poizat O. 
Published: April 2005

AbstractThe combination of ab initio calculation using the CIS method and experimental vibrational data from picosecond time‐resolved Raman measurements leads to a confident picture of the structure of the lowest excited singlet state S1 (nπ*) of 2,2′‐bipyridine. The calculated structure is asymmetric with two dissimilar pyridyl moieties. It can be understood as resulting from a confinement of the excitation in one of the pyridyl rings, breaking the initial ground‐state symmetry. The reliability of this structure is attested by good agreement between the derived theoretical vibrational data and the experimental Raman spectra. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Ab initio calculation of vibrational Raman optical activity
Authors: Pecul Magdalena , Ruud Kenneth 
Published: April 2005

AbstractWe review recent developments in the ab initio calculation of Raman optical activity (ROA) and discuss the applications of modern ab initio methods to the calculation of these properties, giving some examples of the kind of molecules and questions that can now be addressed using ab initio methodology. We also give some perspectives on future developments and applications of theoretical methods as an aid in understanding and analyzing ROA spectra. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005
Isotope ratio mass spectrometry: δ13C and δ15 N analysis for tracing the origin of illicit drugs
Authors: Galimov E. M. , Sevastyanov V. S. , Kulbachevskaya E. V. , Golyavin A. A. 
Published: April 2005

AbstractGas chromatography/combustion/mass spectrometry (GC‐C‐MS) and elemental analysis/mass spectrometry (EA‐MS) techniques are proposed to estimate δ13C and δ15N values in heroin, morphine, cocaine and hemp leaves, for the purposes of tracing the geographical origins of seized drugs. The values of isotope ratios for pure drugs and drugs with impurities were compared. It was demonstrated that large samples (up to 3 × 10−6 g C) were combusted completely, so that the results obtained were valid. The data are considered to be an essential supplement to a wide‐scale database designed specifically for the δ13C and δ15N values of drugs. The potential forensic and academic significance of the results is discussed. Copyright © 2005 John Wiley & Sons, Ltd.
The detection of modafinil and its major metabolite in equine urine by liquid chromatography/mass spectrometry
Authors: McKinney Andrew R. , Suann Craig J. , Stenhouse Allen M. 
Published: April 2005

AbstractA method has been developed for the detection of modafinil and its major metabolite, modafinil acid, in equine urine by solid‐phase extraction and positive ion electrospray ionisation liquid chromatography/mass spectrometry. The method has been applied to the analysis of equine urine samples obtained after the oral administration of modafinil. Modafinil acid was the major component in the urine, and was detected up to 4 days post‐administration. Unchanged modafinil was present at substantially lower concentrations, and was detected for only 24 hours. Copyright © 2005 John Wiley & Sons, Ltd.
Scenarios and simulations for planning Dresdner Bank's E‐day
Authors: Strohhecker Jürgen 
Published: April 2005

AbstractConfronted with the approaching introduction of euro coins and notes, Dresdner Bank's branch managers had to consider that cash‐related transactions between 17 December 2001 and 28 February 2002 would rise much above the normal level. On top of the regular business, the branches had to cope with an unknown amount of exchange transactions of DM into euro. To avoid chaotic situations in the branches and high extra costs, the branches had to prepare themselves. It was, however, unclear what would happen and which measure would be appropriate for which scenario. The branch manager's uncertainty was high. This article shows that the system dynamics method can be successfully applied even to such non‐typical, short‐term, event‐driven problems. Using a feedback perspective, defining the problem dynamically, creating scenarios, developing models and using simulation experiments does not only help to find better strategies but also improves decision making in unique situations with a short‐term focus such as the introduction of the euro coins and notes. Copyright © 2005 John Wiley & Sons, Ltd.
A systems thinking approach to the new administrative capital in Korea: balanced development or not?
Authors: Lee Man‐Hyung , Choi Nam‐Hee , Park Moonseo 
Published: April 2005

AbstractPolitical, economic, and social concentration into the Capital Region, and the resulting problems, have persisted for almost four decades in Korea. To check or reverse the existing trends, the construction of a new administrative capital is being actively discussed. Without due policy designs and application processes, however, the current discussions are not fully adequate in explaining why a new administrative capital is necessary and how it could benefit more balanced regional development. In an effort to address the issue, analytical logics for the proposed new administrative capital are developed using qualitative system dynamics models. To provide policy guidelines, urban dynamics caused by the construction are also analyzed, which include the expected growth and maturity of the new administrative capital city. The research findings indicate that policy intentionally geared towards more balanced regional development through the construction of the new administrative capital city depends on the government's supporting policies that can address and accommodate changes in the regional development system. It is concluded that the system approaches presented here could assist the government in developing robust and responsive policy initiatives given current uncertainties. Copyright © 2005 John Wiley & Sons, Ltd.
Seasonal variation in stomatal conductance and physiological factors observed in a secondary warm‐temperate forest
Authors: Hiyama Tetsuya , Kochi Kiyotaka , Kobayashi Nakako , Sirisampan Satiraporn 
Published: April 2005

AbstractThis study quantified stomatal conductance in a CO2‐fertilized warm‐temperate forest. The study considered five items: (1) the characteristics of the diurnal and seasonal variation, (2) simultaneous measurements of canopy‐scale fluxes of heat and CO2 and the normalized difference vegetation index (NDVI), (3) the stomatal conductance of sunlit and shaded leaves, (4) a stomatal conductance model, and (5) the effects of leaf age on stomatal conductance. Sampled plants included evergreen and deciduous species. Stomatal conductance, SPAD, and leaf nitrogen content were measured between March and December 2001. Sunlit leaves had the largest diurnal and seasonal variation in conductance in terms of both magnitude and variability. In contrast, shaded leaves had only low conductance and slight variation. Stomatal conductance increased sharply in new shooting leaves of Quercus serrata until reaching a maximum 2 months after full leaf expansion. The seasonal changes in the canopy‐scale heat and CO2 fluxes were similar to the change in the canopy‐scale NDVI of the upper‐canopy plants. These seasonal changes were correlated with the leaf‐level H2O/CO2 exchanges of upper‐canopy plants, although these did not represent the stomatal conductance in fall completely. Seasonal variations in the leaf nitrogen content and SPAD were similar, except leaf foliation, until day 130 of the year, when the behaviors were completely the opposite. A Jarvis‐type model was used to estimate the stomatal conductance. We modified it to include SPAD as a measure of leaf age. The seasonal variation in stomatal conductance was not as sensitive to SPAD, although estimates for evergreen species showed improvements.
Incipient offending among schizophrenia patients after first contact to the psychiatric hospital system
Authors: Munkner Runa , Haastrup Soeren , Joergensen Torben , Kramp Peter 
Published: April 2005

AbstractThe study examines how age, sex and substance use disorder are associated with the risk of committing a criminal offence. The study explicitly examines the risk after the first contact to the psychiatric hospital system and after the diagnosis of schizophrenia for those with no previous criminal record; the association between previous non-violent criminality and later violent criminality is also analysed. The study sample comprised 4619 individuals ever diagnosed with schizophrenia. All solved offences were accessible. Data were analysed using Cox's regression. Schizophrenic men had twice the risk of schizophrenic women of committing both violent and non-violent offences. A registered substance use disorder increased the risk 1.9- to 3.7-fold, depending on the starting point for the analyses, while increasing age on first contact or when diagnosed with schizophrenia diminished the risk. Previous non-violent criminality increased the risk for later violent criminality 2.5- to 2.7-fold, depending on the starting point for the analyses. The results suggest that the psychiatric treatment system can play an active role in preventing criminality among individuals with schizophrenia. The preventive measures should be based on a thorough assessment including criminal history at intake and alertness toward young psychotic men with substance use disorders and especially if they also have a criminal history.
Spontaneous appetence for wheel-running: a model of dependency on physical activity in rat
Authors: Ferreira Anthony , Lamarque Stéphanie , Boyer Patrice , Perez-Diaz Fernando , Jouvent Roland , Cohen-Salmon Charles 
Published: April 2005

AbstractAccording to human observations of a syndrome of physical activity dependence and its consequences, we tried to examine if running activity in a free activity paradigm, where rats had a free access to activity wheel, may present a valuable animal model for physical activity dependence and most generally to behavioral dependence. The pertinence of reactivity to novelty, a well-known pharmacological dependence predictor was also tested. Given the close linkage observed in human between physical activity and drugs use and abuse, the influence of free activity in activity wheels on reactivity to amphetamine injection and reactivity to novelty were also assessed. It appeared that (1) free access to wheel may be used as a valuable model for physical activity addiction, (2) two populations differing in activity amount also differed in dependence to wheel-running. (3) Reactivity to novelty did not appeared as a predictive factor for physical activity dependence (4) activity modified novelty reactivity and (5) subjects who exhibited a high appetence to wheel-running, presented a strong reactivity to amphetamine. These results propose a model of dependency on physical activity without any pharmacological intervention, and demonstrate the existence of individual differences in the development of this addiction. In addition, these data highlight the development of a likely vulnerability to pharmacological addiction after intense and sustained physical activity, as also described in man. This model could therefore prove pertinent for studying behavioral dependencies and the underlying neurobiological mechanisms. These results may influence the way psychiatrists view behavioral dependencies and phenomena such as doping in sport or addiction to sport itself.
Patient outcomes in schizophrenia II: the impact of cognition
Authors: Hofer Alex , Baumgartner Susanne , Bodner Thomas , Edlinger Monika , Hummer Martina , Kemmler Georg , Rettenbacher Maria A. , Fleischhacker W. Wolfgang 
Published: April 2005

AbstractBackgroundCognitive dysfunction is increasingly considered to be the strongest clinical predictor of poor long-term outcome in schizophrenia. Associations have been found between the severity of cognitive deficits and social dysfunction, impairments in independent living, occupational limitations, and disturbances in quality of life (QOL).MethodsIn this cross-sectional study, the relationships of cognitive deficits and treatment outcomes in terms of QOL, needs, and psychosocial functioning were examined in 60 outpatients with schizophrenia who had a duration of illness over 2 years and had been treated with either clozapine or olanzapine for at least 6 months.ResultsThe present study suggests that cognitive functioning might be a predictor of work functioning/independent living outcome in stabilized patients with schizophrenia: deficits of visual memory and working memory were negatively associated with occupational functioning, and older patients lived independently and/or in a stable partnership more often. The patients' assessments of QOL and needs for care did not show any significant associations with cognitive functioning.DiscussionThese findings suggest that cognitive functioning is a key determinant of work functioning/independent living for stable outpatients with schizophrenia.
Outreach and support in south London (OASIS): implementation of a clinical service for prodromal psychosis and the at risk mental state
Authors: Broome Matthew R. , Woolley James B. , Johns Louise C. , Valmaggia Lucia R. , Tabraham Paul , Gafoor Rafael , Bramon Elvira , McGuire Philip K. 
Published: April 2005

AbstractBackgroundWhile recent research points to the potential benefits of clinical intervention before the first episode of psychosis, the logistical feasibility of this is unclear.AimsTo assess the feasibility of providing a clinical service for people with prodromal symptoms in an inner city area where engagement with mental health services is generally poor.MethodsFollowing a period of liaison with local agencies to promote the service, referrals were assessed and managed in a primary care setting. Activity of the service was audited over 30 months.ResultsPeople with prodromal symptoms were referred by a range of community agencies and seen at their local primary care physician practice. Over 30 months, 180 clients were referred; 58 (32.2%) met criteria for an at risk mental state, most of whom (67.2%) had attenuated psychotic symptoms. Almost 30% were excluded due to current or previous psychotic illness, of which two-thirds were in the first episode of psychosis. The socio-demographic composition of the 'at risk' group reflected that of the local population, with an over-representation of clients from an ethnic minority. Over 90% of suitable clients remained engaged with the service after 1 year.ConclusionIt is feasible to provide a clinical service for people with prodromal symptoms in a deprived inner city area with a large ethnic minority population.
Growth factors and fibrochondrocytes in scaffolds
Authors: Pangborn Christine A. , Athanasiou Kyriacos A. 
Published: April 2005

AbstractFour growth factors, transforming growth factor‐β1 (TGF‐β1), platelet‐derived growth factor‐AB (PDGF‐AB), insulin‐like growth factor I (IGF‐I), and basic fibroblastic growth factor (bFGF), were tested at different concentrations for their effects on extracellular matrix (ECM) production in three‐dimensional cultures of meniscal fibrochondrocytes. Cells from New Zealand white rabbits were seeded on poly‐glycolic acid (PGA) scaffolds and were stimulated with growth factors for three weeks. 3H‐proline and 35S‐sulfate labels were used to measure uptake of collagen and glycosaminoglycan (GAG) components, respectively. Biochemical assays were performed to measure the total collagen, GAG, and DNA present in the scaffolds at the end of the study. TGF‐β1 (10 and 100 ng/ml) stimulated both 3H‐proline and 35S‐sulfate uptake, showing a dose‐dependent response for both and a temporal response for 35S‐sulfate uptake. IGF‐I (5 ng/ml) and bFGF (25 and 100 ng/ml) showed increases in 3H‐proline uptake by the third week of growth factor addition. PDGF‐AB did not show notable increases in uptake. Because TGF‐β1 (10 and 100 ng/ml) had visibly denser scaffolds, as evidenced by gross microscopy, at 100x, and the strongest uptake responses to both 35S‐sulfate and 3H‐proline, it appears to be the most effective growth factor for use in scaffold‐based approaches to tissue engineer the knee meniscus. © 2005 Orthopaedic Research Society. Published by Elsevier Ltd. All rights reserved.