bluuebunny/crossref_metadata_2025 huggingface dataset:
Determinants of physical activity among Taiwanese adolescents: An application of the health promotion model‡
Authors: Wu Tsu‐Yin , Pender Nola
Published: August 2002

The purpose of this study was to examine the relationships among interpersonal influences (i.e., social support, norms, modeling), behavior‐specific cognitions (i.e., self‐efficacy, perceived benefits/barriers), competing demands, and physical activity among Taiwanese adolescents (N = 832). The results from structural equation modeling indicated that perceived self‐efficacy was the most important predictor of physical activity. Interpersonal influences, when considered in total, had a weak and nonsignificant direct effect on physical activity but had indirect effects on physical activity thorough perceived benefits and perceived self‐efficacy. When sources of interpersonal influences were considered separately, parental influences did not have direct effects on physical activity. In contrast, peers did have a significant direct effect on physical activity and also indirect influences on physical activity through perceived self‐efficacy. All variables accounted for 30% of the variance in physical activity. Results of this study identify important influences useful to health professionals for promoting physical activity in this population. © 2002 John Wiley & Sons, Res Nurs Health 25:25–36, 2002.
A note on the robust control of Markov jump linear uncertain systems
Authors: de Farias D. P. , Geromel J. C. , do Val J. B. R.
Published: August 2002

This note addresses a robust control problem of continuous‐time jump linear Markovian systems subject to norm‐bounded parametric uncertainties. The problem is expressed in terms of a H∞ control problem as in the purely deterministic case. The present formulation is simpler and it contains previous results in the literature as particular cases. Robust state feedback controllers are parameterized by means of a set of linear matrix inequalities. The result is illustrated by solving some examples numerically. Copyright © 2002 John Wiley & Sons, Ltd.
Grafting of hyperbranched poly(amidoamine) onto carbon black surfaces using dendrimer synthesis methodology
Authors: Tsubokawa Norio , Satoh Toshiya , Murota Masamichi , Sato Shimpei , Shimizu Hiroshi
Published: August 2002

To modify carbon black surface, the surface grafting of hyperbranched poly(amidoamine) onto the surface by using dendrimer synthesis methodology was investigated. Carbon black having amino groups (initiator sites) was prepared by the reduction of surface nitro groups introduced by nitration of aromatic rings. It was found that hyperbranched poly(amidoamine) was propagated from carbon black surface by repeating two processes: (1) Michael addition of methyl acrylate (MA) to surface amino groups and (2) amidation of the resulting esters with ethylenediamine: the percentage of poly(amidoamine) grafting reached to 96.2% after 10th‐generation. The grafting of hyperbranched poly(amidoamine) onto polystyrene‐bead as a model compound of carbon black was also achieved by the above procedures. However, the theoretical propagation of poly(amidoamine) dendrimer was not achieved, because of steric hindrance of grafted polymer. Hyperbranched poly(amidoamine)‐grafted carbon black gave a stable dispersion in a good solvent for poly(amidoamine). Copyright © 2001 John Wiley & Sons, Ltd.
The first trimester ‘combined test’ for the detection of Down syndrome pregnancies in 4939 unselected pregnancies
Authors: Schuchter K. , Hafner E. , Stangl G. , Metzenbauer M. , Höfinger D. , Philipp K.
Published: August 2002

The high detection rate (DR) for Down syndrome (DS) pregnancies which can be achieved by measuring fetal nuchal translucency (NT) early in pregnancy can be improved by combining it with placental hormones [pregnancy‐associated plasma protein A (PAPP‐A) and free β‐human chorionic gonadotrophin (fβ‐hCG)] and maternal age (‘combined test’). In this study we wanted to assess the DR using the ‘combined test’ in an unselected population of self‐referred pregnant women at a false‐positive rate (FPR) of about 5%. NT, PAPP‐A, fβ‐hCG and maternal age were measured in all women with singleton pregnancies who booked for delivery in our hospital from 1 December 1997 to 31 April 2000 and who were between 10 and 13 completed weeks of gestation [crown–rump length (CRL) 35–70 mm]. The specific DS risk was calculated using the computer program Alpha Version 5aa (Logical Medical Systems, London, UK). A total of 4939 women were tested. Out of 14 DS pregnancies that occurred during this period of time, 12 were detected with the test. A total of 246 women had a false‐positive test result in a non‐DS pregnancy (FPR 5.0%). This makes the ‘combined test’ by far the best test for the detection of DS pregnancies in a low‐risk population. The constant increase in maternal age at the time of delivery can also lead to an improved DR if a simple age‐dependant protocol for DS detection is used, but only at the price of a much higher number of amniocenteses and subsequent abortions. The DR for DS can be increased much more markedly using the ‘combined test’ with a FPR that still remains at the level as it was in the early 1970s. Copyright © 2002 John Wiley & Sons, Ltd.
Prenatal diagnosis of partial monosomy 18p(18p11.2→pter) and trisomy 21q(21q22.3→qter) with alobar holoprosencephaly and premaxillary agenesis
Authors: Chen Chih‐Ping , Chern Schu‐Rern , Wang Wayseen , Lee Chen‐Chi , Chen Wen‐Lin , Chen Li‐Feng , Chang Tung‐Yao , Tzen Chin‐Yuan
Published: August 2002

A prenatal diagnosis of partial monosomy 18p(18p11.2→pter) and trisomy 21q(21q22.3→qter) in a fetus with alobar holoprosencephaly (HPE) and premaxillary agenesis (PMA) but without the classical Down syndrome phenotype is reported. A 27‐year‐old primigravida woman was referred for genetic counselling at 21 weeks' gestation due to sonographic findings of craniofacial abnormalities. Level II ultrasonograms manifested alobar HPE and median orofacial cleft. Cytogenetic analysis and fluorescence in situ hybridization (FISH) on cells obtained from amniocentesis revealed partial monosomy 18p and a cryptic duplication of 21q,46,XY,der(18)t(18;21)(p11.2;q22.3), resulting from a maternal t(18;21) reciprocal translocation. The breakpoints were ascertained by molecular genetic analysis. The pregnancy was terminated. Autopsy showed alobar HPE with PMA, pituitary dysplasia, clinodactyly and classical 18p deletion phenotype but without the presence of major typical phenotypic features of Down syndrome. The phenotype of this antenatally diagnosed case is compared with those observed in six previously reported cases with monosomy 18p due to 18;21 translocation. The present study is the first report of concomitant deletion of HPE critical region of chromosome 18p11.3 and cryptic duplication of a small segment of distal chromosome 21q22.3 outside Down syndrome critical region. The present study shows that cytogenetic analyses are important in detecting chromosomal aberrations in pregnancies with prenatally detected craniofacial abnormalities, and adjunctive molecular investigations are useful in elucidating the genetic pathogenesis of dysmorphism. Copyright © 2001 John Wiley & Sons, Ltd.
Troglitazone (Rezulin) and hepatic injury
Authors: Faich Gerald A. , Moseley Richard H.
Published: August 2002

Purpose

Analyze US rates of reported severe liver disease for the oral hypoglycemic agent troglitazone from March 1997 through February 2000 and the possible effects of publicity on reporting.

Methods

The number of troglitazone reports with liver failure and or hospitalization with jaundice or hyperbilirubinemia, made to the FDA and/or Parke‐Davis are used as numerators. The denominators are numbers of patients and person‐time estimates of exposure. Additionally, the amount of publicity about troglitazone during its marketing is quantified.

Results

Approximately 1.92 million patients were treated with troglitazone from March 1997 through the end of February 2000 resulting in 1.6 million person‐years of exposure. Reports of 83 cases of liver failure associated with troglitazone were received (1 in 23 000 patients or 1 in 20 000 person‐years). Of the 83 cases, only 49 (59%) were classified by a hepatologist to be ‘possibly’ or ‘probably’ attributed to troglitazone. For the first, second, and third years of marketing, rates of reported hepatic failure per 100 000 person years exposure to troglitazone were 8.3, 5.3, and 2.7 respectively. Rates of reported liver disease involving hospitalizations with mention of jaundice and hyperbilirubinemia per 100 000 person‐years were 16.0, 6.1, and 3.6 respectively for these years. During the 3‐year marketing history of troglitazone, there were 470 lay press and 158 medical literature articles with mentions of hepatotoxicity for the drug.

Conclusions

Rates of reported severe liver disease declined substantially during the second and third years of marketing of troglitazone. The decline followed increasingly stringent requirements for liver function test monitoring and may have been due to improved patient selection and management as a result of the widely publicized association between troglitazone and hepatotoxicity. Copyright © 2001 John Wiley & Sons, Ltd.
Electrochemically stimulated 2‐ethylhexyl phosphate (EHP) release through redox switching of conducting polypyrrole film and polypyrrole/poly (N‐methylpyrrole) or self‐doped polyaniline bilayers
Authors: Massoumi Bakhshali , Entezami Ali Akbar
Published: August 2002

2‐Ethylhexyl phosphate (EHP) released from poly(pyrrole 2‐ethylhexyl phosphate) (PP‐EHP) was investigated at open circuit and compared with electrochemically stimulated release during potential cycling. It was found that the fast EHP release from the PP‐EHP single layer is substantially retarded and that amounts of spontaneously and electrochemically released EHP can be reduced by constructing bilayers, consisting of a PP‐EHP inner layer and a poly(N‐methylpyrrole)‐poly(styrene sulfonate) (PNMP‐PSS) or self‐doped poly(aniline) sulfonate (SPANI) as the outer films. The presence of outer film over the PP‐EHP allowed surface‐property modification, as well as the control of the rate of EHP release, while electrochemically stimulated EHP release from inner films was not substantially hampered by the outer layer. The quantity of the EHP released was investigated using UV‐vis spectrophotometery and an electrochemical quartz‐crystal microbalance (EQCM) during reduction of PP‐EHP from single layer and bilayers through electrochemical stimulation. EHP was reincorporated to the inner film by applying an anodic potential and then the release of EHP was performed again. The results showed that the outer film could act as a barrier to ion‐and solvent‐transport between the inner film and electrolyte, yielding a more balanced counter‐directional movement of anions.

© 2002 Society of Chemical Industry
Observing collaborative problem‐solving processes and outcomes
Authors: Wilczenski Felicia L. , Bontrager Terry , Ventrone Paula , Correia Margaret
Published: August 2002

This study examined the problem of assessing group process in a collaborative problem‐solving situation. Students in seven collaborative groups worked on a two‐part math and logic problem—first individually, then in groups, and finally, individually again. Groups engaging in behaviors that facilitated collaboration obtained higher group and individual accuracy scores on a challenging problem set. High‐achieving students were influential in group problem‐solving outcomes. Group scores did not reflect the individual achievement of low‐achieving students. Examining collaborative group process and outcomes offers a new direction in functional and contextualized assessment for school psychologists. © 2001 John Wiley & Sons, Inc.
Probing the influence of stereoelectronic effects on lithium affinity in 1,3‐ and 1,4‐dioxa systems
Authors: Ganguly Bishwajit , Fuchs Benzion
Published: August 2002

A combined computational and structural study of the lithium affinity (LA) of O—C—O systems exhibiting the anomeric effect and of O— C—C—O systems exhibiting the gauche effect is presented. QM ab initio calculations using the MP2/6–31G* basis set were carried out on the gas‐phase lithium affinities of dimethoxymethane (DMOM), dimethoxyethane (DMOE), 1,3‐dioxane (DOX) and cis‐ and trans‐tetraoxadecalin (TOD), along with that of dimethyl ether and of its dimer as reference compounds. Structural parameters were retrieved from the Cambridge Structural Database (CSD) for diethyl ether dimer and O—C—C—O lithium complexes and these agreed well with the calculated data. The computed lithium affinities of dimethoxymethane and dimethoxyethane were found to be conformationally dependent. The LAs are conformationally dependent (wherever applicable) and decrease in the order: (Me2O)2 > DMOE > DMOM > DOD > DOX > trans‐TOD, but cis‐TOD restores the high LA (better than DMOE) by virtue of multiple coordination. Copyright © 2001 John Wiley & Sons, Ltd.
Preparation and properties of novel polyimides derived from 4‐aryl‐2,6 bis(4‐amino phenyl)pyridine
Authors: Tamami Bahman , Yeganeh Hamid
Published: August 2002

To prepare novel polyimides with enhanced thermal stability and high solubility in common organic solvents, diamine monomers, 4‐aryl‐2,6 bis‐(4‐amino phenyl)pyridine, were introduced. The diamines were reacted with three different conventional aromatic dianhydrides including pyromellitic dianhydride, benzophenone tetracarboxylic dianhydride, and hexafluoroisopropylidene‐2,2‐bis(phthalic‐dianhydride) (6FDA) in dimethylacetamide solvent to obtain the corresponding polyimides via the polyamic acid precursors and chemical imidization. The monomers and polymers were characterized by Fourier transform infrared spectroscopy, 1H NMR, mass spectroscopy, and elemental analysis; and the best condition of polymerization and imidization were obtained via the study of model compound. The polyimides showed little or no weight loss by thermogravimetric analysis up to 500 °C, and those derived from 6FDA exhibited good solubility in various polar solvents. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3826–3831, 2001
Free‐radical copolymerization of 3‐phthalimido‐2‐hydroxypropyl methacrylate with styrene: The determination of monomer reactivity ratios and thermal analysis studies
Authors: Coşkun M. Fatih , Demirelli Kadir , Güzel Dilek , Coşkun Mehmet
Published: August 2002

Free‐radical copolymerizations of styrene and phthalimido‐2‐hydroxypropyl methacrylate (PHPMA) were carried out at 60 °C in a 1,4‐dioxane solution in the presence of 2,2′‐azobisisobutyronitrile at low conversions (<15%). The copolymer compositions were established by elemental analysis. The monomer reactivity ratios r1 (PHPMA) and r2 (styrene) were determined with the linearized copolymerization equations of the Kelen–Tüdös and inverted Fineman–Ross methods and with the nonlinear relationship of the Mayo–Lewis method to be r1 = 1.41 and r2 = 0.24, r1 = 1.52 and r2 = 0.26, and r1 = 1.15 and r2 = 0.16, respectively. The monomer reactivity ratios and glass‐transition temperatures of the copolymers as functions of the copolymer composition are discussed. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 650–658, 2002; DOI 10.1002/pola.10140
Effect of the structure of amphiphilic poly(ethylene glycol)‐containing graft copolymers on styrene emulsion polymerization
Authors: Chern Chorng‐Shyan , Lee Cheng
Published: August 2002

Amphiphilic graft copolymers consisting of monomeric units of poly(ethylene glycol) monomethyl ether acrylate, lauryl or stearyl methacrylate, and 2‐hydroxyethyl methacrylate were synthesized and characterized. The effectiveness of these poly(ethylene glycol)‐containing graft copolymers in stabilizing styrene emulsion polymerization was evaluated. The polymerization rate (Rp) increases with increasing graft copolymer concentration, initiator concentration, or temperature. At a constant graft copolymer concentration, Rp increases, and the amount of coagulum decreases with the increasing hydrophilicity of graft copolymers. The polymerization system does not follow Smith–Ewart case II kinetics. The desorption of free radicals out of latex particles plays an important role in the polymerization kinetics. The overall activation energy and the activation energy for the radical desorption process are 85.4 and 34.3 kJ/mol, respectively. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1608–1624, 2002
Radical and cationic polymerizations of 3‐ethyl‐3‐methacryloyloxymethyloxetane
Authors: Sato Tsuneyuki , Oki Takayuki , Seno Makiko , Hirano Tomohiro
Published: August 2002

3‐Ethyl‐3‐methacryloyloxymethyloxetane (EMO) was easily polymerized by dimethyl 2,2′‐azobisisobutyrate (MAIB) as the radical initiator through the opening of the vinyl group. The initial polymerization rate (Rp) at 50 °C in benzene was given by Rp = k[MAIB]0.55 [EMO]1.2. The overall activation energy of the polymerization was estimated to be 87 kJ/mol. The number‐average molecular weight (M̄n) of the resulting poly(EMO)s was in the range of 1–3.3 × 105. The polymerization system was found to involve electron spin resonance (ESR) observable propagating poly(EMO) radicals under practical polymerization conditions. ESR‐determined rate constants of propagation (kp) and termination (kt) at 60 °C are 120 and 2.41 × 105 L/mol s, respectively—much lower than those of the usual methacrylate esters such as methyl methacrylate and glycidyl methacrylate. The radical copolymerization of EMO (M1) with styrene (M2) at 60 °C gave the following copolymerization parameters: r1 = 0.53, r2 = 0.43, Q1 = 0.87, and e1 = +0.42. EMO was also observed to be polymerized by BF3OEt2 as the cationic initiator through the opening of the oxetane ring. The M̄n of the resulting polymer was in the range of 650–3100. The cationic polymerization of radically formed poly(EMO) provided a crosslinked polymer showing distinguishably different thermal behaviors from those of the radical and cationic poly(EMO)s. © 2001 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 39: 1269–1279, 2001
Synthesis of new photoresponsive polyesters containing norbornadiene residues by the polyaddition of donor–acceptor norbornadiene dicarboxylic acid diglycidyl ester with dicarboxylic acids and their photochemical properties
Authors: Konno Yousuke , Kameyama Atsushi , Nishikubo Tadatomi , Nagai Takabumi
Published: August 2002

A donor–acceptor norbornadiene derivative, 5‐(4‐methoxyphenyl)‐1,4,6,7,7‐pentamethyl‐2,5‐norbornadiene‐2,3‐dicarboxylic acid diglycidyl ester (D–A NDGE), was synthesized by the reaction of the cesium salt of 5‐(4‐methoxyphenyl)‐1,4,6,7,7‐pentamethyl‐2,5‐norbornadiene‐2,3‐dicarboxylic acid with epibromohydrin in N‐methyl‐ pyrrolidone (NMP). The polyaddition reactions of D–A NDGE with certain dicarboxylic acids were carried out with tetrabutylammonium bromide as a catalyst in NMP, producing corresponding polyesters containing D–A norbornadiene (NBD) residues in the main chain in fair to good yields. The photoisomerization of the D–A NBD residues in the polyesters proceeded very smoothly, forming the corresponding quadricyclane groups. The photoreactivities of the D–A NBD residues in the polymer were 50 times higher than those of the NBD residues in the film state and 60 times higher than those in a tetrahydrofuran solution. The stored energy in the quadricyclane groups of the polymers was about 45–55 kJ/mol according to differential scanning calorimetry analysis of the irradiated polymer films. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 2683–2690, 2001
Morphology and crystallization kinetics of dilute binary blends of two monodisperse n‐alkanes with a length ratio of two
Authors: Hosier I. L. , Bassett D. C.
Published: August 2002

The crystallization kinetics and morphologies of dilute binary blends of the monodisperse alkane n‐C122H246 in n‐C246H494 and vice versa have been investigated. With a molecular length ratio close to two, this pair of n‐alkanes does not produce permanent cilia when once‐folded C246H494 molecules cocrystallize with extended chains of C122H246. In this condition, the supplementary splaying of adjacent dominant lamellae and the consequently more spherulitic textures, which are present in previous blends for which a longer guest molecule gives permanent cilia, are absent, although other features of blend crystallization remain. Specifically, the isothermal radial growth rate is constant for cocrystallizing blends, although less than for their pure hosts, but becomes nonlinear with cellulation when C122H246 forms a segregated population within extended‐chain C246H494. Increased nucleation in the blends give smaller scale textures than for the host materials, but the presence of a second component reduces splaying and thereby disfavors spherulitic growth. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2874–2887, 2001
Rubbing‐induced molecular alignment and its relaxation in polystyrene thin films
Authors: Tsang O. C. , Xie Fengchao , Tsui O. K. C. , Yang Z. , Zhang Jianmin , Shen Deyan , Yang Xiaozhen
Published: August 2002

Rubbing‐induced molecular alignment and its relaxation in polystyrene (PS) thin films are studied with optical birefringence. A novel relaxation of the alignment is observed that is distinctly different from the known relaxation processes of PS. First, it is not the Kohlrausch–Williams–Watts type but instead is characterized by two single exponentials plus a temperature‐dependent constant. At temperatures several degrees or more below the glass‐transition temperature (Tg), the relaxation time falls between that of the α and β relaxations. Second, the decay time constants are the same within 40% for PS with weight‐average molecular weights (Mw's) of 13,700–550,000 Da at temperatures well below the sample Tg's, indicating that the molecular relaxations involved are mostly local within the entanglement distance. Nonetheless, the temperature at which the rubbing‐induced molecular alignment disappears (T0) exhibits a strong Mw dependence and closely approximates the Tg of the sample. Furthermore, T0 depends notably on the thickness of the polymer in much the same way as previously found for the Tg of supported PS films. This suggests that the α process becomes dominant near Tg. Preliminary spectroscopic studies in the mid‐infrared range show a significant degree of bending of the phenyl ring toward the sample surface, with the CC bond connecting the phenyl ring and the main chain tends to lie along the rubbing direction, which indicates that the relaxation is connected with the reorientation of this CC bond. We exclude the observed relaxation, as predominantly a near‐surface one, because detailed studies on the effects of rubbing conditions on the degree of molecular alignment indicate that the alignment is not local to the polymer–air surface. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2906–2914, 2001
Predictors of affective responses of mothers and fathers of children with cancer
Authors: Frank Natalie C. , Brown Ronald T. , Blount Ronald L. , Bunke Victoria
Published: August 2002

We investigated predictors of affective responses for 125 parents (77 mothers, 48 fathers) of children with various types of cancer who varied in time of diagnosis from newly diagnosed to 13 years following cancer treatment. The primary rationale of the investigation was to determine whether cognitive appraisals, perceived social supports, and caregivers' perceptions of children's behavior would predict affective responses differentially for mothers and fathers. We defined affectivity as self‐reported depressive symptoms, and state and trait anxiety symptoms. Parents did not differ on any of the variables, including affective responses, although differential predictors of affective responses were revealed for mothers and fathers. Affiliation‐related attributions were associated with affective responses for mothers, and achievement‐related attributions and perceived social support were associated with affective responses for fathers. Copyright © 2001 John Wiley & Sons, Ltd.
Stratified scree in the Central Spanish Pyrenees: palaeoenvironmental implications
Authors: García‐Ruiz J. M. , Valero‐Garcés B. , González‐Sampériz P. , Lorente A. , Martí‐Bono C. , Beguería S. , Edwards L.
Published: August 2002

Sedimentological, geomorphological and palynological study of three stratified screes from two environments in the central Spanish Pyrenees allows reconstruction of climate and vegetational change since the last glacial maximum. In both localities (at 700 and 1000 m a.s.l.) the deposits show a similar stratigraphy: (i) a basal stratified scree, in one case fossilized by speleothems; (ii) a palaeosol, with abundant charcoal and evidence of human activity; and (iii) a massive coarse scree. The stratified scree developed during the glacial maximum and late glacial. A humid period during the early Holocene was characterized by speleothem formation and carbonate cementation in some screes. Forest fires around 3300 BP were widespread in the Pyrenees and were probably related to human impact. Recent scree reactivation due to an increase in clast supply is limited to cold stages during the late Holocene. Copyright © 2001 John Wiley & Sons, Ltd.
Bronchodilatory effects of salbutamol, ipratropium bromide, and their combination: Double‐blind, placebo‐controlled crossover study in cystic fibrosis
Authors: Ziebach Rita , Pietsch‐Breitfeld Barbara , Bichler Matthias , Busch Andreas , Riethmüller Joachim , Stern Martin
Published: August 2002

The efficacy of inhaled sympathomimetic and anticholinergic agents on airway obstruction in cystic fibrosis (CF) has been proven in several studies. However, studies comparing combined therapy with monotherapy led to divergent results, probably due to different study designs, different dosages, and the small numbers of patients investigated. Therefore, we wanted to answer the question which inhalation has the best short term effect: a sympathomimetic or an anticholinergic agent, or the combination of both. We investigated 17 patients with CF on 4 successive days in the morning, using pulmonary function testing before and 30 min after inhalation. Each patient received aerosolized salbutamol (SB, maximum dose (max.) 2.5 mg), ipratropium bromide (IB, max. 0.5 mg), the combination of both, or placebo (normal saline) in a randomized, double‐blind crossover design.

The mean forced expiratory volume in the first second improved significantly (adjusted P‐value < 0.017) after each treatment compared to placebo. Analysis of variance showed that SB and combination therapy with SB and IB were superior to IB alone, without significant difference between SB and combination therapy. Response of a patient to combined therapy was usually associated with response to SB. Long‐term efficacy and side effects of treatment with bronchodilators still remain to be investigated after this short term study.

We conclude that in CF patients bronchodilator therapy with sympathomimetic agents is usually sufficient. Only in cases with proven additional benefit from inhalation by anticholinergics should combination therapy be recommended. Pediatr Pulmonol. 2001; 31:431–435. © 2001 Wiley‐Liss, Inc.
Fluctuations in ion pairs and their stabilities in proteins
Authors: Kumar Sandeep , Nussinov Ruth
Published: August 2002

This report investigates the effect of systemic protein conformational flexibility on the contribution of ion pairs to protein stability. Toward this goal, we use all NMR conformer ensembles in the Protein Data Bank (1) that contain at least 40 conformers, (2) whose functional form is monomeric, (3) that are nonredundant, and (4) that are large enough. We find 11 proteins adhering to these criteria. Within these proteins, we identify 22 ion pairs that are close enough to be classified as salt bridges. These are identified in the high‐resolution crystal structures of the respective proteins or in the minimized average structures (if the crystal structures are unavailable) or, if both are unavailable, in the “most representative” conformer of each of the ensembles. We next calculate the electrostatic contribution of each such ion pair in each of the conformers in the ensembles. This results in a comprehensive study of 1,201 ion pairs, which allows us to look for consistent trends in their electrostatic contributions to protein stability in large sets of conformers. We find that the contributions of ion pairs vary considerably among the conformers of each protein. The vast majority of the ion pairs interconvert between being stabilizing and destabilizing to the structure at least once in the ensembles. These fluctuations reflect the variabilities in the location of the ion pairing residues and in the geometric orientation of these residues, both with respect to each other, and with respect to other charged groups in the remainder of the protein. The higher crystallographic B‐factors for the respective side‐chains are consistent with these fluctuations. The major conclusion from this study is that salt bridges observed in crystal structure may break, and new salt bridges may be formed. Hence, the overall stabilizing (or, destabilizing) contribution of an ion pair is conformer population dependent. Proteins 2001;43:433–454. © 2001 Wiley‐Liss, Inc.
Anabaena apoflavodoxin hydrogen exchange: On the stable exchange core of the α/β(21345) flavodoxin‐like family
Authors: Langdon Grant M. , Jiménez M. Angeles , Genzor Carlos G. , Maldonado Susana , Sancho Javier , Rico Manuel
Published: August 2002

An important issue in modern protein biophysics is whether structurally homologous proteins share common stability and/or folding features. Flavodoxin is an archetypal α/β protein organized in three layers: a central β‐sheet (strand order 21345) flanked by helices 1 and 5 on one side and helices 2, 3, and 4 on the opposite side. The backbone internal dynamics of the apoflavodoxin from Anabaena is analyzed here by the hydrogen exchange method. The hydrogen exchange rates indicate that 46 amide protons, distributed throughout the structure of apoflavodoxin, exchange relatively slowly at pH 7.0 (kex < 10−1 min−1). According to their distribution in the structure, protein stability is highest on the β‐sheet, helix 4, and on the layer formed by helices 1 and 5. The exchange kinetics of Anabaena apoflavodoxin was compared with those of the apoflavodoxin from Azotobacter, with which it shares a 48% sequence identity, and with Che Y and cutinase, two other α/β (21345) proteins with no significant sequence homology with flavodoxins. Both similarities and differences are observed in the cores of these proteins. It is of interest that a cluster of a few structurally equivalent residues in the central β‐strands and in helix 5 is common to the cores. Proteins 2001;43:476–488. © 2001 Wiley‐Liss, Inc.
Uptake and translocation of carpropamid in rice (Oryza sativa L)
Authors: Rohilla Rashmi , Singh Uma S , Singh R L
Published: August 2002

Translocation of the antiblast compound, carpropamid, was investigated in rice using [14C]carpropamid. When applied to the seed, carpropamid was not only readily absorbed but was translocated to different parts of the seedlings emerging from treated seeds. A substantial portion of fungicide appeared to be exuded onto the leaf surface. In 21‐day‐old plants grown from [14C]carpropamid‐treated seeds, 27.2% of the radioactivity isolated from leaves was present on the surface of lamina. This exuded fraction is probably responsible for its action as a fungal anti‐penetrant compound. Following 30‐min root dipping of 14‐day‐old seedlings, carpropamid was rapidly absorbed and translocated throughout the seedling. Its intra‐laminar distribution was uniform as determined by autoradiography. Only a small fraction (<2%) of fungicide applied to the foliage was translocated beyond the site of application within the treated leaf. Translocation was primarily apoplastic. Approximately 54% of the radioactivity recovered from leaves was in the form of carpropamid. At least seven radiolabelled metabolic products were observed by TLC. Only 8.3% of radioactivity applied through the seeds could be recovered from 21‐day‐old seedlings.

© 2001 Society of Chemical Industry
Modern structural wood products
Authors: Lam Frank
Published: August 2002

A Correction has been published for this article in Progress in Structural Engineering and Materials 3(4) 2001, 361.

Engineered wood products are structural composites that have been gaining successes in the construction industry. The mechanical and physical properties of these products depend on the interacting relationships between the quality of the resource, the manufacturing process, and the applications. In general their mechanical properties are more uniform compared with solid sawn material; hence, higher allowable properties are available in engineering design. This paper reviews the manufacturing processes, structural properties, physical attributes, and common applications of some of the major engineered wood products including: glued‐laminated timber, parallel strand lumber, laminated strand lumber, laminated veneer lumber, and thick oriented strand board/rimboard.
Chemoprotective potentials of homoisoflavonoids and chalcones of Dracaena cinnabari: modulations of drug‐metabolizing enzymes and antioxidant activity
Authors: Machala Miroslav , Kubínová Renata , Hořavová Pavla , Suchý Václav
Published: August 2002

A series of homoisoflavonoids and chalcones, isolated from the endemic tropical plant Dracaena cinnabari Balf. (Agavaceae), were tested for their potential to inhibit cytochrome P4501A (CYP1A) enzymes and Fe‐enhanced in vitro peroxidation of microsomal lipids in C57B1/6 mouse liver. The effects of the polyphenolic compounds were compared with those of prototypal flavonoid modulators of CYP1A and the well‐known antioxidant, butylated hydroxytoluene. 2‐Hydroxychalcone and partly 4,6‐dihydroxychalcone were found to be strong inhibitors of CYP1A‐dependent 7‐ethoxyresorufin O‐deethylase (EROD) activity in vitro comparable to the effects of quercetin and chrysin. The first screening of flavonoids and chalcones of Dracaena cinnabari for antioxidant activity was done in an in vitro microsomal peroxidation assay. While chalcones were shown to be poor antioxidants, 7,8‐methylenedioxy‐3(4‐hydroxybenzyl) chromane, as one of the tested homoisoflavonoids, exhibited a strong antioxidant activity comparable to that of the strongest flavonol antioxidant, quercetin. Copyright © 2001 John Wiley & Sons, Ltd.
Hepatoprotective action of an oleanolic acid‐enriched extract of Ligustrum lucidum fruits is mediated through an enhancement on hepatic glutathione regeneration capacity in mice
Authors: Yim T. K. , Wu W. K. , Pak W. F. , Ko K. M.
Published: August 2002

The fruits of Ligustrum lucidum Ait. (FLL) were fractionated into petroleum ether (FLL‐Pe), chloroform (FLL‐Ch), butanol (FLL‐Bu) and aqueous (FLL‐Aq) fractions, of which FLL‐Ch and FLL‐Bu were found to be enriched with oleanolic acid (OLA). The in vivo antioxidant activities of various FLL fractions and OLA were assessed by examining the effect on carbon tetrachloride (CCl4)‐induced hepatotoxicity in mice. Pretreatment of animals with various FLL fractions could protect against CCl4‐induced hepatotoxicity to a varying degree, with OLA‐enriched FLL‐Bu and FLL‐Ch being more potent. However, a mortality rate of 60% was observed in the FLL‐Ch pretreated and CCl4‐intoxicated mice. OLA pretreatment also produced a dose‐dependent protection against CCl4 hepatotoxicity. The hepatoprotection afforded by FLL‐Bu or OLA pretreatment was associated with an enhancement of hepatic­glutathione regeneration capacity (GRC). In contrast, the inability of FLL‐Aq pretreatment to enhance hepatic GRC resulted in a failure to prevent CCl4‐induced hepatic injury. The results suggest that the hepatoprotective action afforded by OLA‐enriched FLL‐Bu or OLA pretreatment may be mainly mediated by the enhancement of hepatic GRC, particularly under conditions of CCl4‐induced oxidative stress. Copyright © 2001 John Wiley & Sons, Ltd.
Pycnogenol® efficacy in the treatment of systemic lupus erythematosus patients
Authors: Stefanescu M. , Matache C. , Onu A. , Tanaseanu S. , Dragomir C. , Constantinescu I. , Schönlau F. , Rohdewald P. , Szegli G.
Published: August 2002

A pilot study was performed to evaluate the efficacy of Pycnogenol® treatment in systemic lupus erythematosus (SLE) patients. Eleven SLE patients were treated with first line medication according to disease activity and in addition, six of them received Pycnogenol® and five a placebo. The SLE disease activity index (SLEDAI), serum anti‐dsDNA antibodies, fibrinogen, C‐reactive protein levels, erythrocyte sedimentation rate, production of reactive oxygen species (ROS) by neutrophils, spontaneous apoptosis and p56lckspecific activity in peripheral blood lymphocytes were evaluated. Pycnogenol® treatment determined a significant reduction of ROS production, apoptosis, p56lckspecific activity and erythrocyte sedimentation rate. In addition, the decrease of SLEDAI was significant in the Pycnogenol® treated group compared with the placebo group (p= 0.018). The results obtained suggest that Pycnogenol® could be useful for second line therapy to reduce the inflammatory feature of SLE. Copyright © 2001 John WIley & Sons, Ltd.
Semiempirical INDO/S study on the solvatochromism of merocyanine dyes
Authors: Bicca de Alencastro Ricardo , Da Motta Neto Joaquim Delphino
Published: August 2002

We report results of semiempirical intermediate neglect of differential overlap (INDO/S) calculations on the spectroscopy of 4′‐hydroxy‐1‐methylstilbazolium betaine (HMSBB). Solvent effects were included using both the continuum and supermolecule approaches. The calculated spectra are compared with experimental ultraviolet‐visible spectra for several solvents. The odd bathochromic shift of the low energy band (for nonpolar solvents) is tentatively discussed in terms of the contributions of different solvation mechanisms, and an assignment based on INDO/S calculated spectra is presented. We start from the assumption that in solution, conformations other than the completely planar structure (A) are possible. For protic solvents, in which hydrogen bonding constitutes the main contribution to solvation, calculations using the planar, fully optimized AM1 geometry reproduce fairly well the observed spectra. The intense, π→π* band is calculated close to 20,000 cm−1, in good agreement with the experimental values in water and methanol. For the very polar formamide, the INDO/S+SCRF result is also very accurate, suggesting that formamide's strong polarity induces HMSBB to adopt the planar structure A. For polar solvents with nonspecific interactions such as acetonitrile or dimethylformamide, the situation is not as clear. We speculate that the experimental numbers can be reproduced only by a very large supermolecule. Finally, for nonpolar solvents such as cyclohexane, benzene and CCl4, the experimental number of 16,141 cm−1 (previously obtained from extrapolation of solvent mixtures by Jacques and coworkers) is reproduced by the INDO/S method only considering structures B and C. These results can be considered a confirmation of Jacques' suggestion that the solvatochromism of HMSBB can be explained by the solvents inducing a geometry change in HMSBB. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Excited states of Na and Al iso‐electronic ions: Symmetry adapted cluster–configuration interaction study
Authors: Das A. K. , Ehara M. , Nakatsuji H.
Published: August 2002

The Rydberg excited levels of s, p, d, and f symmetries are studied up to principal quantum number n=5 for the first eight members of the Na iso‐electronic sequence (Na to Ar7+) and for the first six members of the Al iso‐electronic sequence (Al to Ar5+) by the symmetry adapted cluster–configuration interaction (SAC–CI) method. The valence Slater‐type orbital (STO) basis sets of Clementi et al. and the optimized Rydberg STO functions are used by the STO‐6G expansion method. The calculated transition energies agree well with the experimental values wherever available. The results for the 4f level of S3+ and for the 5s, 4p, 5p, and 4f levels of Cl4+ and Ar5+ are predicted for the first time. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Solvable quartic potentials and their isospectral partners
Authors: Peña J. J. , Ovando G. , Morales‐Guzmán D. , Morales J.
Published: August 2002

In this work, we present an operational method based on the use of supersymmetry applied to quantum mechanics, shape invariance, and intertwining techniques to determine certain classes of solvable potentials. Our proposal uses an ansatz which matches the Witten superpotential, allowing us to identify, through a particular Ricatti relationship, the potentials that are solvable as well as to obtain straightforwardly the corresponding ground state eigenvalues, energy, and wave function. As a useful application of the proposed method, we obtain some examples of solvable quartic potentials as well as, with the aid of the standard and generalized Darboux transform, the partner isospectral potentials that are associated with the models under consideration. The method can be easily extended and used to find new solvable potentials which could be useful in the modeling of specific quantum interactions. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Density functional study of the structural, electronic, and magnetic properties of neutral and charged rhodium clusters up to tetramer
Authors: Lacaze‐Dufour Corinne , Mineva Tzonka , Russo Nino
Published: August 2002

Model core potential computations were performed for Rh2, Rh3, and Rh4 clusters and their respective cations and anions using the linear combination of Gaussian‐type orbital, nonlocal spin density method. The optimized geometries, electronic and magnetic structures, binding and fragmentation energies, adiabatic ionization potentials, and electron affinities were determined. Results show that the ionization potentials, electron affinities, binding energies, and magnetic moments decrease with the cluster size. For Rh2 and Rh3 the most stable structures exhibit ferromagnetic properties, while Rh4 in its ground state is found to be paramagnetic. The structures of minimum energy for the charged species often differs from the corresponding neutral one. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Generalized spin density functional theory for noncollinear molecular magnetism II—Influence of gradient correction and self‐interaction correction
Authors: Yamanaka S. , Yamaki D. , Kiribayashi S. , Yamaguchi K.
Published: August 2002

We have implemented generalized spin orbital (GSO) based localized spin density approximation (LSDA) and general gradient approximation (GGA) calculations for noncollinear magnetic systems. Further self‐interaction correction (SIC) within a perturbational scheme is applied for the GSO solutions of LSDA and GGA. The Boys localization is employed to obtain appropriate SIC orbitals. The calculational results are compared with those of generalized Hartree–Fock (GHF) methods and full configuration interaction (FCI). From our calculations of equilateral and isosceles triangular H3 molecule, it was found that SIC improves significantly the feature of potential surface as well as the total energy values. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Optical spectroscopy of (C2H5NH3)2CdCl4:Cu2+ under pressure: Study of Cu2+ local structure from theoretical calculations
Authors: Valiente R. , Rodríguez F. , Aramburu J. A. , Moreno M. , Barriuso M. T. , Sousa C. , de Graaf C.
Published: August 2002

The variations experienced by the energy Eu(π) of the eu(π)→b1g (∼x2–y2) charge‐transfer transition of (C2H5NH3)2CdCl4:Cu2+ upon pressure in the 0‐ to 40‐kbar range have been measured at room temperature by means of a sapphire anvil cell. These data reveal that Eu(π) undergoes a red shift of 1400 cm−1 on passing from ambient pressure to 40 kbars. To understand this puzzling result theoretical calculations of ∂Eu(π)/∂Req and ∂Eu(π)/∂Rax have been performed where Req and Rax mean the equatorial and axial Cu2+–Cl− distances of the elongated CuCl64− complex, respectively. All results indicate that ∂Eu(π)/∂Req and ∂Eu(π)/∂Rax for Req=228 pm and Rax=297 pm are indeed negative. Moreover ab initio complete active space self‐consistent field (CASSCF/CASPT2) and density functional calculations lead to ∂Eu(π)/∂Rax values, which are about 10 times smaller than those of ∂Eu(π)/∂Req. From the ensemble of experimental and theoretical results, it is concluded that a pressure of 40 kbars gives rise to a decrement of ≈25 pm of the axial distance and at the same time to an increase of ≈7 pm of the equatorial one. It is stressed that the present study on a diluted Jahn–Teller impurity lies far beyond the current possibilities of X‐ray absorption structure techniques. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Ab initio calculation and quasi‐classical dynamics study of the two lowest potential energy surfaces of the O(1D)+HBr system*
Authors: Hernández María Luz , Alvariño José María , Laganà Antonio , Rosi Marzio , Sgamellotti Antonio
Published: August 2002

The lowest singlet 11A′ and 11A″ potential energy surfaces (PES) of the O(1D)+HBr system have been ab initio computed. The complete active space self‐consistent field (CASSCF) method was used in most of the calculations, considering all the valence orbitals as active. The calculations were complemented with both analytical gradient calculations to characterize the stationary points and multireference configuration interaction (MRCI) calculations at selected nuclear geometries to improve the determination of the barrier heights and of the energetics. Electronic energy values for both PESs were then independently fitted by polynomial expansions in bond order coordinates. On the fitted surfaces quasi‐classical trajectories were separately run. Single‐surface calculations behave qualitatively different for the ground and the excited PES at low collision energies. A satisfactory agreement with existing experimental data was obtained by using the ground PES while calculations performed on the excited 11A″ PES worsened the agreement. However, when collision energy is increased, detailed experimental distributions are less well reproduced by calculations on the ground PES. This may imply the participation via nonadiabatic transitions of the 21A′ PES at higher energies while the adiabatic ground singlet PES well describes reactive scattering at low collision energy. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
High‐level ab initio study of the N+(3P)+SH2reactions in the gas phase: Role of spin‐forbidden pathways
Authors: Ijjaali Fatima , Alcamí Manuel , Mó Otilia , Yáñez Manuel
Published: August 2002

The singlet and triplet potential energy surfaces involved in N++SH2reactions have been explored using high‐level ab initio techniques. The geometries of the stationary points were optimized at the QCISD/6‐311G(df,p) level. The final energies were obtained in CCSD(T)/6‐311+G(3df,2p) single‐point calculations. The results obtained show that, although the N+(1D)+SH2entrance channel is higher in energy than the N+(3P)+SH2one, most of the [H2, S, N]+singlet state cations are lower in energy than the corresponding triplets, due to their different bonding characteristics. Both singlet and triplet potential energy surfaces are quite close each other, and crossover between them can occur. The minimum energy crossing points were located by means of CASSCF(6,5) calculations. The spin‐orbit couplings show that the transition probability from the triplet to the singlet potential energy surface is significantly large. One of the most important consequences is that some of the products of the reaction, such as SH+, can be formed in typical spin‐forbidden processes. Since all the relevant structures along these pathways are much lower in energy than the reactants, this mechanism should be accessible even at low impact energies and therefore could be important in processes taking place in interstellar media. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001