bluuebunny/crossref_metadata_2025 huggingface dataset:
Gallium Contacts onp‐type silicon substrates
Authors: Stuckings M. F. , Fischer B. , Giroult G. , Cuevas A. , Stocks M. J. , Blakers A. W.
Published: August 2002

A significant reduction in contact resistance of palladium/silicon contacts was realised by the use of a thin intermediate gallium layer. The contact resistance of the palladium/gallium/silicon contact was found to be similar to aluminium/silicon contacts on 0.5 Ω cm silicon. Solar cells processed on 1 Ω cm substrates with this structure demonstrated better contact properties than conventional aluminium/silicon contacts. The improved characteristics are believed to be a result of gallium/silicon alloying at low temperature (400°C). The palladium layer is critical as aluminium/gallium/silicon layers show dramatically increased contact resistance. The palladium silicide may interact with the aluminium layer to form a stable ternary compound, preventing aluminium from penetrating deeper into the silicon. Copyright © 2001 John Wiley & Sons, Ltd.
Manufacturing technology for terrestrial PV systems: high efficiency crystalline Si through amorphous Si
Authors: Kaneiwa Minoru , Nomoto Katsuhiko
Published: August 2002

In order to meet the rapidly growing demands for solar power photovoltaic systems, grounded on public consciousness of global environmental issues, Sharp has increased the production of solar cells and modules 50‐fold in last 7 years. Efforts to establish manufacturing technologies of solar cells for terrestial use and approaches toward high light‐to‐electricity conversion efficiency using silicon material (crystalline to amorphous ) are described. Copyright © 2002 John Wiley & Sons, Ltd.
Manufacturing technology for ribbon silicon (EFG) wafers and solar cells
Authors: Schmidt W. , Woesten B. , Kalejs J.P.
Published: August 2002

Manufacturing of wafers and solar cells based on edge‐defined film‐fed growth (EFG) ribbon technology has been scaled up to 20 MW in the ASE group. Highly automated manufacturing lines for wafers and solar cells have been constructed and solar cell efficiencies optimized to above the 14% level. The technology developed for these production lines incorporates new low‐cost processes with minimal environmental impact and waste materials production. Copyright © 2002 John Wiley & Sons, Ltd.
Photophysical characteristics of soluble oligo(p‐phenylenevinylene)–fullerene dyad
Authors: Yang Junlin , Lin Hongzhen , Wang Shu , Li Yuliang , Bai Fenglian , Zhu Daoben
Published: August 2002

The fact that C60 is a good acceptor has stimulated interest in covalently linked complexes, including polymers and oligomers. Photoinduced charge transfer in these systems has great potential for use in photovoltaic devices. In this study, an alternating conjugated oligomer of alkylated carbazole and dialkoxyl‐substituted phenylene, with pendant C60 moieties, (PPV‐AFCAR) was prepared and characterized. The excited‐state properties of PPV–AFCAR were investigated with steady‐state spectroscopy and lifetime measurements. After photoexcitation, photoinduced energy transfer from the oligomer chain to the pendant moiety occurred in great proportion, but a charge‐separation process did not. Whether the energy‐transfer process was measurable or not depended on the system temperature. At 77 K, a quantum yield of more than 50% for energy transfer was found by the fitting of a linear combination of the excitation spectra of the precursor oligomer, the alternating conjugated oligomer of alkylated carbazole and dialkoxyl‐substituted phenylene PPV–ACAR, and the absorption spectra of C60. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3981–3988, 2001
Determination of the equilibrium constant for the reaction between bisphenol A and diphenyl carbonate
Authors: Gross Stephen M. , Bunyard W. Clayton , Erford Karen , Roberts George W. , Kiserow Douglas J. , DeSimone Joseph M.
Published: August 2002

Despite the industrial significance of poly(bisphenol A carbonate), there is a scarcity of open literature on the equilibrium of the melt‐phase process. In fact, the equilibrium constant (Keq) for this reaction has never been measured directly. This article describes a process on the basis of NMR for the measurement of Keq for the reaction between bisphenol A and diphenyl carbonate in the presence and absence of a catalyst. The apparent enthalpy and entropy were calculated using a van't Hoff plot. Decomposition of bisphenol A is a common side reaction in the melt‐phase reaction performed at high temperatures in the presence of catalyst. The effect of these side reactions on the Keq in the presence of catalyst is determined. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 40: 171–178, 2002
Synthesis and properties of aromatic polyamides based on a benzonorbornane bis(ether carboxylic acid)
Authors: Hsiao Sheng‐Huei , Huang Tai‐Lin
Published: August 2002

A set of new aromatic polyamides containing ether and benzonorbornane units were synthesized by the direct phosphorylation polycondensation of 3,6‐bis(4‐carboxyphenoxy)benzonorbornane with various aromatic diamines. The polymers were produced in high yields and moderate to high inherent viscosities (0.64–1.70 dL/g). The polyamides derived from rigid diamines such as p‐phenylenediamine and benzidine were semicrystalline and insoluble in organic solvents. The other polyamides were amorphous and organosoluble and afforded flexible and tough films via solution casting. These films exhibited good mechanical properties, with tensile strengths of 95–101 MPa, elongations at break of 13–25%, and initial moduli of 1.97–2.33 GPa. The amorphous polyamides showed glass‐transition temperatures between 176 and 212 °C (by differential scanning calorimetry) and softening temperatures between 194 and 213 °C (by thermomechanical analysis). Most of the polymers did not show significant weight loss before 450 °C in nitrogen or in air. Some properties of these polyamides were also compared with those of homologous counterparts without the pendent norbornane groups. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 947–957, 2002
Photochemical modification of polymer surface by the pendant photobase generator containing oxime‐urethane groups and its application to an image‐recording material
Authors: Chae Kyu Ho , Jang Hee Jung
Published: August 2002

Copolymers containing oxime‐urethane groups were prepared by the copolymerization of methyl methacrylate and benzophenoneoximinocarbonylaminoethyl methacrylate (BCM), and their photochemical properties were examined from the UV and IR absorption spectral changes. The decomposed fraction of oxime‐urethane groups in the copolymer increased with irradiation time, but it decreased with the content of BCM units in the copolymer. Changes of the surface properties of the copolymer film on irradiation were studied by measurements of the contact angle and dyeing with an acid dye. The surface of the copolymer film changed to become more hydrophilic upon irradiation with 254 nm of UV light. After the irradiated copolymer films were treated with HCl or methanol, changes of the contact angle of water on irradiation were compared. The copolymer film was dyed by acid dyes after treatment of the irradiated film with HCl. The degree of dyeing increased with irradiation time and BCM units in the copolymer, but it was unaffected by the film thickness. Various colors were developed on the irradiated area depending on the acid dye as the developer. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1200–1207, 2002
Synthesis of well‐defined second‐generation dendritic polymers of isoprene (I) and styrene (S): (S2I)3, (SI′I)3, (I″I′I)3, and (I′2I)4
Authors: Chalari Ioanna , Hadjichristidis Nikos
Published: August 2002

The synthesis of second‐generation (G‐2) dendritic polymers of isoprene (I) and styrene (S) was achieved with anionic polymerization high‐vacuum techniques and by performing the following steps: (1) selective reaction of a living chain with the chlorosilane group of 4‐(chlorodimethylsilyl)styrene (a dual‐functionality compound) to produce a macromonomer, (2) addition of a second living chain (same or different) to the double bond of the macromonomer, (3) polymerization of I with the anionic sites, and (4) reaction of the produced off‐center living species with trichloromethyl silane or tetrachlorosilane (CH3SiCl3 or SiCl4). The combined characterization results showed that the G‐2 dendritic macromolecules synthesized—(S2I)3, (SI′I)3, (I″I′I)3, (I′2I)4—have a high molecular and compositional homogeneity. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1519–1526, 2002
Synthesis of multihydroxyl branched polyethers by cationic copolymerization of 3,3‐bis(hydroxymethyl)oxetane and 3‐ethyl‐3‐(hydroxymethyl)oxetane
Authors: Chen Yu , Bednarek Melania , Kubisa Przemysław , Penczek Stanisław
Published: August 2002

The cationic ring‐opening polymerization of 3,3‐bis(hydroxymethyl)oxetane (BHMO) and the copolymerization of BHMO with 3‐ethyl‐3‐(hydroxymethyl)oxetane (EOX) were studied. Medium molecular weight polymers (number‐average molecular weight ≈ 2 × 103) were obtained in bulk polymerization. Poly[3,3‐bis(hydroxymethyl)oxetane], as highly insoluble, was only characterized by gel permeation chromatography and NMR methods in the esterified form. Copolymers of BHMO and EOX that were slightly soluble in organic solvents were characterized in more detail. In a copolymerization from a 1:1 mixture, the comonomers were consumed at equal rates. Matrix‐assisted laser desorption/ionization time‐of‐flight analysis confirmed that a random 1:1 copolymer was formed. 13C NMR analysis indicated that in contrast to previously described homopolymers of EOX in which the degree of branching was limited, the homopolymers of BHMO were highly branched. This pattern was preserved in the copolymers; EOX units were predominantly linear, whereas BHMO units were predominantly branched. The copolymerization of BHMO with EOX provides, therefore, a route to multihydroxyl branched‐polyethers with various degrees of branching containing OH groups exclusively as ≡CCH2OH units. © 2002 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 1991–2002, 2002
Reversible nonlinear conduction behavior for high‐density polyethylene/graphite powder composites near the percolation threshold
Authors: Zheng Qiang , Song Yihu , Wu Gang , Yi Xiaosu
Published: August 2002

The reversible nonlinear conduction (RNC) behavior of high‐density polyethylene/graphite powder composites with various graphite powder volume concentrations slightly above the threshold has been studied. The relationships between the current density (J) and electric field (E) of the composites, as shown in J(E) curves, can be well described by the scaling functions of J/Jc ∼ (E/Ec) when E < Ec and J/Jc ∼ (E/Ec) when E > Ec, where Jc is the crossover current density and Ec is the crossover electric field. The results indicate that Jc scales with the linear conductivity σ0 as Jc ∼ σ. It is believed that the macroscopic RNC is a combined result of the microscopic conduction processes, involving electronic transporting along carbon chains and tunneling or hopping across thin polymer bridges. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2833–2842, 2001
Hydrogels for colon‐specific drug delivery: Swelling kinetics and mechanism of degradation in vitro
Authors: Yin Yihua , Yang Yajiang , Xu Huibi
Published: August 2002

Hydrogels based on n‐alkyl methacrylate esters (n‐AMA) of various chain lengths, acrylic acid, and acrylamide crosslinked with 4,4′‐di(methacryloylmino)azobenzene were prepared. Swelling kinetics and the mechanism of degradation in vitro of the hydrogels as well as the mutual relations between both were studied by the immersion of slabs in buffered solutions at pH 7.4. The diffusion of water into the slabs was discussed on the stress‐relaxation model of polymer chains. The results obtained agreed well with Schott's second‐order diffusion kinetics. The gels are degradable by anaerobes in the colon. The results obtained showed that the degradation of networks proceeded via a pore mechanism. The factors influencing the swelling and degradation of the gels include the degree of crosslinking, the lengths of the n‐AMA side chains, and the composition. These hydrogels have the potential for colon‐specific drug delivery. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 3128–3137, 2001
Bonding of a viscoelastic periodic rough surface to a rigid layer
Authors: Hui C. Y. , Lin Y. Y. , Creton Costantino
Published: August 2002

A theoretical analysis is performed for the study of the bonding of a viscoelastic rough surface to a rigid substrate. The mechanics of contact and adhesion are studied with the Dugdale–Barenblatt model for surface interaction. Exact solutions are obtained for arbitrary surface profiles and loading histories. Detailed solutions are given for a power‐law viscoelastic material. This solution is used to determine the time for the self‐bonding of surfaces (solid sintering under zero load). The time to self‐bonding is shown to be extremely sensitive to the aspect ratio of the asperities. A closed form expression is derived for the time needed to achieve full contact when the surfaces are compressed with a load that increases linearly with time. © 2002 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 40: 545–561, 2002; DOI 10.1002/polb.10113
X‐ray studies on the double melting behavior of poly(butylene terephthalate)
Authors: Yasuniwa Munehisa , Tsubakihara Shinsuke , Ohoshita Kazuhito , Tokudome Shin'Ichi
Published: August 2002

The double melting behavior of poly(butylene terephthalate) (PBT) was studied with differential scanning calorimetry (DSC) and wide‐angle X‐ray analysis. DSC melting curves of melt‐crystallized PBT samples, which we prepared by cooling from the melt (250 °C) at various cooling rates, showed two endothermic peaks and an exothermic peak located between these melting peaks. The cooling rate effect on these peaks was investigated. The melt‐crystallized PBT sample cooled at 24 K min−1 was heated at a rate of 1 K min−1, and its diffraction patterns were obtained successively at a rate of one pattern per minute with an X‐ray measurement system equipped with a position‐sensitive proportional counter. The diffraction pattern did not change in the melting process, except for the change in its peak height. This suggests that the double melting behavior does not originate from a change in the crystal structure. The temperature dependence of the diffraction intensity was obtained from the diffraction patterns. With increasing temperature, the intensity decreased gradually in the low‐temperature region and then increased distinctly before a steep decrease due to the final melting. In other words, the temperature‐dependence curve of the diffraction intensity showed a peak that is interpreted as proof of the recrystallization in the melting process. The peak temperature was 216 °C. The temperature‐dependence curve of the enthalpy change obtained by the integration of the DSC curve almost coincided with that of the diffraction intensity. The double melting behavior in the heating process of PBT is concluded to originate from the increase of crystallinity, that is, recrystallization. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2005–2015, 2001
Young's modulus of polyethylene in the microstrain region
Authors: Rabinowitz Stephen , Brown Norman
Published: August 2002

The stress–strain behavior of various polyethylenes was measured with a strain sensitivity of 2 × 10−7. Young's modulus was measured as a function of the strain rate. The shapes of the stress–strain curves in the vicinity of room temperature were nonlinear down to the lowest measurable strain. The stress–strain behavior in the microstrain region was well described by the model of the standard linear solid. From the model, the relaxation time was determined along with the relaxed and unrelaxed moduli. © 2001 John Wiley & Sons, Inc. J Polym Sci Part B: Polym Phys 39: 2420–2429, 2001
From evidence to practice: Factors affecting the specialist breast nurse's detection of psychological morbidity in women with breast cancer
Authors: Parle Michael , Gallagher Jill , Gray Christine , Akers Gina , Liebert Barbara
Published: August 2002

Psychological morbidity is high for women with breast cancer and is often undetected and untreated. Encouragingly, there are well‐evaluated strategies to help improve psychological outcomes, but the challenge remains as to how to transfer these to routine care settings. The National Health and Medical Research Council (NHMRC) National Breast Cancer Centre used evidence‐based psychosocial clinical practice guidelines and breast cancer treatment guidelines to develop a comprehensive specialist breast nurse (SBN) model of care and conducted a feasibility study to observe its implementation in diverse clinical conditions. Seven SBNs at four Australian cancer treatment centres implemented the model of care to support 196 women with a new diagnosis of early or locally advanced breast cancer. The SBN role in detecting women's psychological difficulties is reported here. Two months after diagnosis, 36% of women had a likely psychological disorder on the General Health Questionnaire 12‐item (GHQ12) version. The SBNs detected as many as 85% and as few as 20% of high GHQ12 scorers, depending upon a woman's psychosocial risk factors and consultation factors. Few women were referred to psychological services, suggesting other barriers to care. More specific communication skills training, psychological symptom screening questionnaires and better access to psychological services may help the implementation of the model of care. Copyright © 2001 John Wiley & Sons, Ltd.
Daily assessment of coping in patients with gastrointestinal cancer
Authors: Wasteson Elisabet , Nordin Karin , Hoffman Katarina , Glimelius Bengt , Sjödén Per‐Olow
Published: August 2002

Ninety‐five patients with gastrointestinal (GI) cancer participated in a study concerning stressful events, coping and emotional well‐being. Participants were either potentially cured (n=62) after radical surgery or non‐cured (n=33). For a period of 1 week, close to being informed about their diagnosis, they performed daily recordings of stressful events, the distress occasioned by these events and their perception of control over them, coping, worry and happiness/sadness. Anxiety and depression were assessed by a single retrospective assessment at the end of the week (Hospital Anxiety and Depression (HAD) scale). The most commonly recorded stressful events were ‘Somatic aspects’ and ‘Everyday concerns’. ‘Somatic aspects’, ‘Social aspects’ and ‘Other consequences of the disease’ were rated as most bothersome. Patients perceived that they had the highest degree of control over ‘Returning home after hospital stay’, whereas ‘Contact with the medical services’ was assigned low control. The most commonly used coping strategies were ‘Acceptance’ and ‘Relaxation’, and the least used was ‘Religion’. Significant positive correlations between the occurrence of stressful events and the use of coping strategies were demonstrated between ‘Somatic Aspects’ and ‘Acceptance’/‘Direct Action’, and between ‘Social Aspects’ and ‘Seeking Social Support’. Daily assessment of stress‐coping relationships represents a promising approach to the understanding of adaptation among cancer patients. Copyright © 2002 John Wiley & Sons, Ltd.
The assessment of potential geotechnical hazards associated with mountain permafrost in a warming global climate
Authors: Harris Charles , Davies Michael C. R. , Etzelmüller Bernd
Published: August 2002

European mountain permafrost is generally only a few degrees below zero Celsius, and may therefore be highly sensitive to climate change. Permafrost degradation may lead to thaw settlement and reduction in the stability of mountain slopes. Engineering projects within the high mountain zone require careful investigations of potential permafrost‐related hazards. This paper summarizes a staged approach to such investigations. Phase 1 involves walkover site survey supported by a desk study to define potential permafrost hazard zones. Data from permafrost distribution maps, topographic and geological maps are integrated, preferably using GIS methodology. If permafrost is possible and is judged to pose a significant threat to the development, phase 2 investigations are recommended whereby field thermal measurements, drilling of exploratory boreholes, and geophysical surveys are undertaken to clarify permafrost characteristics. The resulting data set should form an important component in subsequent engineering design. On a larger scale, a similar approach should be adopted as part of land‐use planning within the mountain permafrost zone. Copyright © 2001 John Wiley & Sons, Ltd.

Généralement, le pergélisol européen de montagne est seulement quelques degrés en dessous du zéro Celsius et est, de ce fait, très sensible aux changements climatiques. La dégradation du pergélisol peut entraîner des affaissements du sol au dégel et une réduction de la stabilité des pentes de montagne. Des projets d'ingénierie dans la haute montagne exigent donc des recherches soigneuses concernant les risques potentiels liés à l'existence du pergélisol. Le présent article résume une approche en différentes étapes d'une telle recherche. La phase 1 consiste en un examen attentif du terrain, travail suivi par une étude en laboratoire afin de définir les zones potentielles où existerait un pergélisol dangereux. Des données provenant de cartes de la distribution du pergélisol ainsi que de cartes topographiques et géologiques doivent être intégrées en utilisant si possible un système d'information géographique. Si un pergélisol est possible et paraît constituer une menace, une deuxième phase de recherches est recommandée. Elle comprendra des mesures de température sur le terrain, la réalisation de forages d'exploration et des levés géophysiques pour définir les caractéristiques du pergélisol. Les données recueillies constitueront une partie importante du projet d'ingénierie. A une échelle plus grande, une approche semblable devrait être adoptée dans toute étude visant à modifier l'affectation de terrains dans la zone du pergélisol de montagne. Copyright © 2001 John Wiley & Sons, Ltd.
Strategies for improving transition to adult cystic fibrosis care, based on patient and parent views*
Authors: Boyle Michael P. , Farukhi Zareen , Nosky Michelle L.
Published: August 2002

Although general principles guiding the transition of individuals with chronic illness from pediatric to adult care have been established, guidelines specific for the transition of individuals with cystic fibrosis (CF) have not. To aid in the development of CF‐specific transition guidelines, an anonymous pretransition questionnaire and posttransition interview were used to assess the concerns and expectations of 60 CF patients and their parents as they went through the transition from pediatric to adult care. Along with demographic and clinical information, respondents were asked to rate on a scale of 1–5 their general attitude toward, or level of concern on 22 questions involving transition concerns, adult program expectations, and general view of transition.

The two most important concerns identified by patients prior to transition to adult care were potential exposure to infection (3.4 ± 1.3) and having to leave their previous caregivers (3.4 ± 1.0). Introduction to the adult CF team prior to transition was associated with significantly lower levels of concern in all areas, particularly about having to leave previous caregivers (3.9 ± 0.7 vs. 2.5 ± 0.6, P < 0.004). Age, gender, severity of lung disease, and age at diagnosis were not predictive of level of concern for any area. Parents' most significant concern was ability of their child to care for their CF independently, a concern their children did not share (4.0 ± 1.1 vs. 1.5 ± 0.5, P < 0.0001). As their most important expectations for the adult program, patients identified ready phone access to a nurse (4.9 ± 0.6) and education about adult CF issues (4.6 ± 0.7). The overall attitude toward the development of an adult CF program was overwhelmingly positive for both patients (4.9 ± 0.7) and parents (4.9 ± 0.3).

By allowing patients to interact with the adult team prior to transition and developing transition protocols which address CF‐specific issues like infection control and fertility, successful transition from pediatric to adult cystic fibrosis care can be accomplished. Pediatr Pulmonol. 2001; 32:428–436. © 2001 Wiley‐Liss, Inc.
Association of codon 72 polymorphism of p53 with lower prostate cancer risk
Authors: Henner Wm. David , Evans Adam J. , Hough Kristi M. , Harris Emily L. , Lowe Bruce A. , Beer Tomasz M.
Published: August 2002

Background

A common germline polymorphism of p53 produces a protein with an Arg to Pro change at codon 72. This Pro variant has altered biochemical properties suggesting altered cancer susceptibility.

Methods

A case control study with 115 men with prostate cancer and 181 community control male subjects was conducted. Demographics, family history of cancer, and blood were obtained. Codon 72 genotypes were determined using PCR.

Results

The Pro/Pro genotype was associated with a markedly lower risk of prostate cancer (OR = 0.23, CI = 0.07–0.79, P = 0.012). Similar reduction in risk was observed when the analysis was limited to Caucasian subjects (86% of total). Reduction in risk remained significant in a logistic regression model after correcting for age and family history of prostate cancer (OR = 0.14, CI = 0.03–0.71, P = 0.017).

Conclusions

Men with the p53 codon 72 Pro/Pro genotype appear to be at reduced risk of prostate cancer. Prostate 49:263–266, 2001. © 2001 Wiley‐Liss, Inc.
Predicting the disulfide bonding state of cysteines using protein descriptors
Authors: Mucchielli‐Giorgi M.H. , Hazout S. , Tufféry P.
Published: August 2002

Knowledge of the disulfide bonding state of the cysteines of proteins is of major interest in designing numerous molecular biology experiments, or in predicting their three‐dimensional structure. Previous methods using the information gained from aligned sets of sequences have reached up to 82% of success in predicting the oxidation state of cysteines. In the present study, we assess the relative efficiency of different descriptors in predicting the cysteine disulfide bonding states. Our results suggest that the information on the residues flanking the cysteines is less informative about the disulfide bonding state than about the amino acid content of the whole protein. Using a combination of logistic functions learned with subsets of proteins homogeneous in terms of their amino acid content, we propose a simple prediction approach, starting from a single sequence, that reaches success rates close to 84%. This score can be improved by avoiding predictions regarding cysteines for which the decision is not well marked. For example, we obtain a score close to 87% correct prediction when we exclude predicting 10% of the cysteines. Proteins 2002;46:243–249. © 2002 Wiley‐Liss, Inc.
New insights into the mechanism of protein–protein association
Authors: Selzer Tzvia , Schreiber Gideon
Published: August 2002

Association of a protein complex follows a two‐step mechanism, with the first step being the formation of an encounter complex that evolves into the final complex. Here, we analyze recent experimental data of the association of TEM1‐β‐lactamase with BLIP using theoretical calculations and simulation. We show that the calculated Debye–Hückel energy of interaction for a pair of proteins during association resembles an energy funnel, with the final complex at the minima. All attraction is lost at inter‐protein distances of 20 Å, or rotation angles of >60° from the orientation of the final complex. For faster‐associating protein complexes, the energy funnel deepens and its volume increases. Mutations with the largest impact on association (hotspots for association) have the largest effect on the size and depth of the energy funnel. Analyzing existing evidence, we suggest that the transition state along the association pathway is the formation of the final complex from the encounter complex. Consequently, pairs of proteins forming an encounter complex will tend to dissociate more readily than to evolve into the final complex. Increasing directional diffusion by increasing favorable electrostatic attraction results in a faster forming and slower dissociating encounter complex. The possible applicability of electrostatic calculations for protein–protein docking is discussed. Proteins 2001;45:190–198. © 2001 Wiley‐Liss, Inc.
Seed treatment with β‐aminobutyric acid protects Pennisetum glaucum systemically from Sclerospora graminicola
Authors: Shailasree S , Sarosh B R , Vasanthi N S , Shetty H S
Published: August 2002

β‐Aminobutyric acid (BABA) treatment of pearl millet [Pennisetum glaucum (L) R Br] seeds influenced seedling vigour and protected the seedlings from downy mildew disease caused by the oomycetous biotropic fungus Sclerospora graminicola (Sacc) Schroet. Of the different concentrations of BABA tested, viz 25, 50, 75 and 100 mM, seeds treated with 50 mM for 6 h resulted in the maximum of 1428 seedling vigour and showed 23% disease incidence in comparison with the control which recorded a seedling vigour of 1260 and 98% disease incidence ie 75% protection from disease. Seeds treated with BABA when challenged for downy mildew disease using zoospores of S graminicola required 48 h after inducer treatment to develop maximum resistance. Durability of induced resistance was also tested in plants raised from seeds treated with the inducer and identified as resistant, by second challenge inoculation with the downy mildew pathogen at tillers and inflorescence axes. Reduced disease incidence of only 10 and 12% in these plants, compared with 71 and 76% disease in control plants inoculated at the tillers and inflorescence axes, respectively, suggested that resistance induced in seeds with BABA remained operative through vegetative and reproductive growth of pearl millet plants. Induction of resistance by seed treatment with BABA enhanced vegetative growth, viz height, fresh weight, leaf area and tillering, and reproductive growth, viz early flowering, number of productive ear heads and 1000 seed weight. Studies on induction of resistance in different cultivars of pearl millet with varying resistance reaction to downy mildew indicated that the protection offered by BABA is independent of the nature of cultivars used and not dependent on their constitutive resistance.

© 2001 Society of Chemical Industry
Control of post‐harvest decay of apples by pre‐harvest and post‐harvest application of ammonium molybdate
Authors: Nunes Carla , Usall Josep , Teixidó Neus , Eribe Xavier Ochoa de , Viñas Immaculada
Published: August 2002

Ammonium molybdate was tested as a potential fungicide for use in apples (cv Golden Delicious) against blue and grey mould, important post‐harvest diseases of pome fruits. In tests in vivo at 20 °C, ammonium molybdate (15 mM) reduced lesion diameters of Penicillium expansum, Botrytis cinerea and Rhizopus stolonifer by 84%, 88% and 100% respectively. When apples treated with ammonium molybdate were stored at 1 °C for three months, a significant reduction in severity and incidence of P expansum and B cinerea was observed in both years of study (1998 and 1999). In the second year of the experiment the reduction in disease severity was greater than 88% for both pathogens, and the level of control was similar to, or greater than, that observed with the fungicide imazalil. When ammonium molybdate was applied as a pre‐harvest treatment, a significant reduction in blue mould decay was observed after three months in cold storage. In vitro, ammonium molybdate greatly inhibited spore germination of P expansum and B cinerea, although better inhibition was obtained against grey mould. Ammonium dimolybdate, sodium molybdate and potassium molybdate were also tested in vitro in comparison with ammonium molybdate as inhibitors of spore germination, but only ammonium molybdate inhibited spore germination by more than 50%.

© 2001 Society of Chemical Industry
Mode of action of acibenzolar‐S‐methyl against sheath blight of rice, caused by Rhizoctonia solani Kühn
Authors: Rohilla Rashmi , Singh U S , Singh R L
Published: August 2002

The mode of action of acibenzolar‐S‐methyl (BTH) was investigated against sheath blight of rice and its pathogen, Rhizoctonia solani. BTH exhibited limited fungitoxicity against R solani, in the form of reduced mycelial growth, hyphal browning and sclerotia formation. Parasite fitness of mycelia and sclerotia formed on BTH‐amended media was also reduced. When applied as soil drench or foliar spray, BTH inhibited both disease development on inoculated sheaths and its spread to the younger sheaths. The degree of protection against sheath blight increased with increase in duration between BTH application and inoculation. The curative effect of BTH was poor. When applied through roots a protective effect of BTH was visible even with only a 1‐h interval between application and inoculation. However, in the case of foliar application, protective effect was recorded only when the gap between application and inoculation was 24 h. BTH reduced the frequency of penetration by R solani, colonization of host tissue and spread of the hyphae from primary lesions to form secondary lesions. BTH induced swelling of hyphal tips on the sheath surface, formation of papillae, browning of penetrated epidermal cells and degeneration of intra‐cellular hyphae colonizing epidermal and mesophyll cells. Therefore, the protective effect of BTH against sheath blight was due to combination of its host defence‐inducing activity and its adverse effect on growth and vigour (parasite fitness) of the pathogen.

© 2001 Society of Chemical Industry
A new strategy for the synthesis of cyclopeptides containing diaminoglutaric acid
Authors: Bayer Tom , Riemer Christoph , Kessler Horst
Published: August 2002

A new synthesis of orthogonally protected diaminoglutaric acid containing peptides using the Ugi four component condensation is presented. To demonstrate that this method is useful to replace cystine by diaminoglutaric acid in biologically interesting peptides, we built up two cyclic somatostatin analogues deriving from Sandostatin and from TT‐232. A photolytically cleavable amine derivative of the nitroveratryl type is used for the Ugi four component condensation. Because of a racemic build up of the new stereocentre of the diaminoglutaric acid, and racemization of the isonitrile component, four diastereomeric peptides resulted that were separated by HPLC. The stereochemistry of the cyclopeptides could be easily and unambiguously assigned by chiral gas chromatography and a reference sample of enantiomerically pure (2S,4S)‐diaminoglutaric acid. Copyright © 2001 European Peptide Society and John Wiley & Sons, Ltd.
Connections in tubular structures
Authors: Kurobane Yoshiaki
Published: August 2002

Tubular structures can be subdivided into two large groups of truss‐type structure: braced multi‐storey frames, and multi‐storey moment resisting frames. Details of connections for trusses vary widely, ranging from two‐ and three‐dimensional tube‐to‐tube connections, reinforced and unreinforced, to variety of plate‐to‐tube connections, which are mainly used for site connections. Moment connections include both the semi‐rigid and fully restrained I‐section beam‐to‐hollow‐section column connections. Considerable effort to improve conventional connection designs has been made during the past 5 years to avoid premature tensile failures experienced during the 1995 Kobe Earthquake. This article reviews recent research developments in the design of these tubular connections. Because many intensive studies have been conducted, studies on connections under fatigue loading and those dealing with concrete‐filled tubes are excluded from this review for the sake of brevity.
Effect of Kava and Valerian on human physiological and psychological responses to mental stress assessed under laboratory conditions
Authors: Cropley M. , Cave Z. , Ellis J. , Middleton R. W.
Published: August 2002

This study investigated whether kava or valerian could moderate the effects of psychological stress induced under laboratory conditions in a group of healthy volunteers. Fifty‐four participants performed a standardized colour/word mental stress task on two occasions 1 week apart. Blood pressure (BP), heart rate (HR) and subjective ratings of pressure were assessed at rest and during the mental stress task. Following the first session (time 1 = T1), individuals took a standard dose of kava (n = 18), or valerian (n = 18) for 7 days, while the remainder acted as controls (n = 18). Differences in BP and HR from resting levels were calculated as reactions to the stress task at both time points. At the second session (time 2 = T2) there was a significant decrease in systolic BP responsivity in both the kava and valerian groups relative to T1, but there were no significant reductions in diastolic BP. Between T1 and T2, the HR reaction to mental stress was found to decline in the valerian group but not in the kava group. Individuals taking kava or valerian reported less pressure during the task at T2 relative to T1. There were no significant differences in BP, HR or subjective reports of pressure between T1 and T2 in the controls. Behavioural performance on the colour/word task did not change between the groups over the two time points. The results suggest that kava and valerian may be beneficial to health by reducing physiological reactivity during stressful situations. Copyright © 2002 John Wiley & Sons, Ltd.
Cytotoxic activity of Typhonium flagelliforme (Araceae)
Authors: Choo Chee‐Yan , Chan Kit‐Lam , Takeya Koichi , Itokawa Hideji
Published: August 2002

The plant Typhonium flagelliforme (Araceae), commonly known as the ‘rodent tuber’, is often included as an essential ingredient in various herbal remedies recommended for cancer therapies in Malaysia. Various extracts prepared from either the roots, tubers, stems or leaves were tested for cytotoxic activity on murine P388 leukaemia cells using the MTT assay method. Both the chloroform (IC50 = 6.0 µg/mL) and hexane (IC50 = 15.0 µg/mL) extract from the ‘roots and tubers’ exhibited weak cytotoxic activity. The hexane extract (IC50 = 65.0 µg/mL) from the ‘stems and leaves’ exhibited weaker cytotoxic activity than the chloroform extract (IC50 = 8.0 µg/mL). Although the juice extract from the ‘roots and tubers’ is frequently consumed for cancer treatment, it exhibited poor cytotoxic activity. Further analysis using an amino acid analyser revealed that the juice extract contained a high concentration of arginine (0.874%). A high tryptophan content (0.800%) was confirmed by NMR and HPLC analysis. Copyright © 2001 John Wiley & Sons, Ltd.
The synthesis of Rantes, G‐CSF, IL‐4, IL‐5, IL‐6, IL‐12 and IL‐13 in human whole‐blood cultures is modulated by an extract from Eleutherococcus senticosus L. roots
Authors: Schmolz M. W. , Sacher F. , Aicher B.
Published: August 2002

An ethanol extract derived from the roots of Eleutherococcus senticosus was found to influence markedly the cytokine synthesis of activated whole blood cultures of ten healthy volunteers. Whereas the synthesis of Rantes was increased over a wide range of concentrations, the release of IL‐4, IL‐5 and IL‐12 was significantly inhibited. An inhibition at higher concentrations, switching to a stimulation at lower doses of the extract was seen with G‐CSF, IL‐6 and IL‐13. From these particular immuno‐pharmacological effects of Eleutherococcus senticosus we suggest this herbal preparation possesses immuno‐modulatory potency, rather than just being immuno‐suppressive or ‐stimulating. Copyright © 2001 John Wiley & Sons, Ltd.
Wound healing activity of acylated iridoid glycosides from Scrophularia nodosa
Authors: Stevenson Philip C. , Simmonds Monique S. J. , Sampson Julia , Houghton Peter J. , Grice Peter
Published: August 2002

Three acylated iridoid glycosides (E)‐6‐O‐(2″, 4″‐diacetyl‐3″ ‐O‐p‐methoxycinnamoyl)‐α‐L‐rhamnopyranosyl catalpol (scopolioside A) (1), (E)‐6‐O‐(2″‐acetyl‐3″, 4″‐di‐O,O‐p‐methoxycinnamoyl)‐α‐L‐rhamnopyranosyl catalpol (scrophuloside A4) (2) and (E)‐6‐O‐(2″,3″‐diacetyl‐4″‐O‐p‐methoxycinnamoyl)‐α‐L‐rhamnopyranosyl catalpol (scrovalentinoside) (3) have been isolated from the dried seed pods of Scrophularia nodosa by HPLC. Their structures were determined by 1D and 2D NMR, UV/Vis and mass spectroscopy and by comparison with published data. All three compounds were shown in vitro to stimulate the growth of human dermal fibroblasts. The effect was negatively dose‐dependent for 2 and 3 for which fibroblast growth stimulation was highest at 0.78 μg/mL but was not significantly different from the control at 100 μg/mL. The presence of these compounds in the mature seed pods may explain the ethnobotanical use of this plant in Europe for healing wounds. Copyright © 2002 John Wiley & Sons, Ltd.
Anxiogenic properties of Ptychopetalum olacoides Benth. (Marapuama)
Authors: da Silva A. L. , Bardini S. , Nunes D. S. , Elisabetsky E.
Published: August 2002

Alcohol infusions of roots of Ptychopetalum olacoides Benth. (PO), known as Marapuama or Muirapuama, are used in the Brazilian Amazon as a ‘nerve tonic’. Over the years PO has been found increasingly in phytoformulations and regarded as a stimulant, claimed to enhance physical and mental performances. This study determined that a P. olacoides ethanol extract (30, 100 and 300mg/kg) decreased exploratory behaviour in the hole‐board test, without interfering with locomotion or motor coordination (rota‐rod test). The data are comparable to that obtained with pentylenetetrazol (40 mg/kg), suggesting an anxiogenic effect of P. olacoides. Copyright © 2002 John Wiley & Sons, Ltd.
Meeting the challenges of implementing good laboratory practices compliance in a university setting
Authors: Hancock Sandra
Published: August 2002

The number of university laboratories participating in good laboratory practices (GLP) studies is on the rise, as evidenced by the increase in university personnel that have joined the Society of Quality Assurance (SQA) during the past decade. However, the road to GLP compliance in the university setting has significant challenges. To evaluate how universities have implemented and managed GLP studies, a survey was conducted of SQA members with a university address. The results are described in this article. At Virginia‐Maryland Regional College of Veterinary Medicine (VMRCVM), we have been participating in GLP studies since 1989. Studies are conducted by research or clinical faculty members, with quality assurance (QA) provided by the College Quality Assurance Unit. Since the inception of our GLP Program, VMRCVM has made significant progress toward meeting the challenges of regulatory compliance. Copyright © 2002 John Wiley & Sons, Ltd.
Temperature effects on the UV–Vis electronic spectrum of trans‐stilbene
Authors: Kwasniewski S. P. , François J. P. , Deleuze M. S.
Published: August 2002

The ultraviolet (UV)–Visible absorption spectrum of trans‐stilbene (tS) is computed at different temperatures by coupling molecular dynamics (MD) simulations with the classical MM3 force field to ZINDO/S‐CIS calculations of vertical excitation energies and transition dipole moments. The selection of a large number of structures along the MD trajectories enables a consistent treatment of temperature effects in the vacuum, whereas the ZINDO/S‐CIS calculations permit a reliable treatment of electron correlation and relaxation, taking account of multistate interactions in the final state. Thermal motions are found to alter very differently the width and shape of bands. Structural alterations such as the stretching and the torsion of the vinyl single and double bonds very strongly influence the appearance of the first valence state, pertaining to the highest occupied and lowest unoccupied molecular orbital (HOMO–LUMO) transition. At temperatures less than 400 K, these are found to yield a merely Gaussian and very pronounced thermal broadening of the related band (A), up to nearly 30 nm, together with a minor blue shift of its maximum λmax. In contrast, a red shift by several nanometers occurs due to thermal motions for the remaining three valence bands. As can be expected, the broadening intensifies at higher temperatures, and for the A‐band, becomes markedly asymmetric when T exceeds 400 K. The combination of MD(MM3) and ZINDO/S‐CIS computations enables also consistent calculations of hot bands, which are forbidden by symmetry at 0 K. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001
Magnetoresistance effect, Runge–Lenz vector, and the torque vector due to anisotropy of electron orbits in cubic lattices submitted to the action of a constant magnetic field
Authors: Olszewski S. , Baszczak M.
Published: August 2002

Parameters due to an anisotropic character of the electron orbits in cubic metals submitted to the action of an external magnetic field are calculated. These parameters are, in the first step, a nonzero value of the metal magnetoresistance and—in the second step—the nonvanishing electron torque vector and the Runge–Lenz vector. Both these vectors depend on the electron angular momentum in the crystal lattices, which is also examined together with the radius of curvature of the electron orbits. The calculation of magnetoresistance is specified to the case of the body‐centered cubic lattice of metallic iron for which a comparison of the theory with the experimental data for magnetoresistance is also presented. © 2002 Wiley Periodicals, Inc. Int J Quantum Chem, 2002
Theoretical study of the internal rotational barriers in nitrobenzene, 2‐nitrotoluene, 2‐nitrophenol, and 2‐nitroaniline
Authors: Chen P. C. , Chen S. C.
Published: August 2002

The molecular geometries and internal rotational barriers of the nitro group of nitrobenzene (NB), 2‐nitrotoluene (2‐NT), 2‐nitroaniline (2‐NA), and 2‐nitrophenol (2‐NP) were calculated by five different types of density functional theory (DFT) methods with three different levels of basis sets. Analysis of the torsional angles of the nitro, methyl, amino, and hydroxyl groups indicate that NB, 2‐NA, and 2‐NP are planar molecules, but 2‐NT is not a planar molecule. Internal rotational barriers of the nitro group were calculated as V2 barriers, and the NO2 torsional potentials for each molecule were given. The values of the V2 barriers depend on the DFT methods and basis sets. The average values of the V2 barriers for NB, 2‐NT, 2‐NA, and 2‐NP are 6.47 kcal/mol, 3.00 kcal/mol, 10.20 kcal/mol, and 13.26 kcal/mol, respectively. © 2001 John Wiley & Sons, Inc. Int J Quant Chem 83: 332–337, 2001
Sum‐frequency generation first hyperpolarizability from time‐dependent Hartree–Fock method
Authors: Quinet Olivier , Champagne Benoît
Published: August 2002

A general time‐dependent Hartree–Fock scheme has been implemented using the 2n+1 rule in order to evaluate the sum frequency generation first hyperpolarizability. It has been applied to estimate the second‐order nonlinear optical response of p‐nitroaniline with one fixed frequency in the ultraviolet (UV) domain and one tunable infrared frequency. This scheme has also been employed to determine the antisymmetric isotropic component of the first hyperpolarizability of chiral molecules including helicenes. © 2001 John Wiley & Sons, Inc. Int J Quantum Chem, 2001