bluuebunny/crossref_metadata_2025 huggingface dataset:
Fruit-Localized Phytochromes Regulate Lycopene Accumulation Independently of Ethylene Production in Tomato
Authors: Alba Rob , Cordonnier-Pratt Marie-Michèle , Pratt Lee H.
Published: July 2002

We show that phytochromes modulate differentially various facets of light-induced ripening of tomato fruit (Solanum lycopersicum L.). Northern analysis demonstrated that phytochrome A mRNA in fruit accumulates 11.4-fold during ripening. Spectroradiometric measurement of pericarp tissues revealed that the red to far-red ratio increases 4-fold in pericarp tissues during ripening from the immature-green to the red-ripe stage. Brief red-light treatment of harvested mature-green fruit stimulated lycopene accumulation 2.3-fold during fruit development. This red-light-induced lycopene accumulation was reversed by subsequent treatment with far-red light, establishing that light-induced accumulation of lycopene in tomato is regulated by fruit-localized phytochromes. Red-light and red-light/far-red-light treatments during ripening did not influence ethylene production, indicating that the biosynthesis of this ripening hormone in these tissues is not regulated by fruit-localized phytochromes. Compression analysis of fruit treated with red light or red/far-red light indicated that phytochromes do not regulate the rate or extent of pericarp softening during ripening. Moreover, treatments with red or red/far-red light did not alter the concentrations of citrate, malate, fructose, glucose, or sucrose in fruit. These results are consistent with two conclusions: (a) fruit-localized phytochromes regulate light-induced lycopene accumulation independently of ethylene biosynthesis; and (b) fruit-localized phytochromes are not global regulators of ripening, but instead regulate one or more specific components of this developmental process.
Interaction between Gravitropism and Phototropism in Sporangiophores ofPhycomyces blakesleeanus
Authors: Grolig Franz , Eibel Peter , Schimek Christine , Schapat Tanja , Dennison David S. , Galland Paul A.
Published: July 2002

The interaction between gravitropism and phototropism was analyzed for sporangiophores of Phycomyces blakesleeanus. Fluence rate-response curves for phototropism were generated under three different conditions: (a) for stationary sporangiophores, which reached photogravitropic equilibrium; (b) for sporangiophores, which were clinostated head-over during phototropic stimulation; and (c) for sporangiophores, which were subjected to centrifugal accelerations of 2.3g to 8.4g. For blue light (454 nm), clinostating caused an increase of the slope of the fluence rate-response curves and an increase of the maximal bending angles at saturating fluence rates. The absolute threshold remained, however, practically unaffected. In contrast to the results obtained with blue light, no increase of the slope of the fluence rate-response curves was obtained with near-ultraviolet light at 369 nm. Bilateral irradiation with near-ultraviolet or blue light enhanced gravitropism, whereas symmetric gravitropic stimulation caused a partial suppression of phototropism. Gravitropism and phototropism appear to be tightly linked by a tonic feedback loop that allows the respective transduction chains a mutual influence over each other. The use of tropism mutants allowed conclusions to be drawn about the tonic feedback loop with the gravitropic and phototropic transduction chains. The results from clinostating mutants that lack octahedral crystals (implicated as statoliths) showed that these crystals are not involved in the tonic feedback loop. At elevated centrifugal accelerations, the fluence-rate-response curves for photogravitropic equilibrium were displaced to higher fluence rates and the slope decreased. The results indicate that light transduction possesses a logarithmic transducer, whereas gravi-transduction uses a linear one.
Changes in the Xanthophyll Cycle and Fluorescence Quenching Indicate Light-Dependent Early Events in the Action of Paraquat and the Mechanism of Resistance to Paraquat in Erigeron canadensis(L.) Cronq
Authors: Váradi Gyula , Darkó Éva , Lehoczki Endre
Published: July 2002

Violaxanthin de-epoxidation, chlorophyll fluorescence quenching, and photosynthetic O2 evolution in the presence of paraquat (Pq) were studied in intact attached leaves of Pq-susceptible, and Pq-resistant (PqR) biotypes of Erigeron canadensis under different light conditions. Initially, similar changes were induced in the two biotypes, but the effects relaxed only in the PqR plants, indicating a Pq elimination process. The penetration of Pq into the chloroplasts of PqR plants proved to be somewhat restricted and highly light-dependent, as revealed by both the light response curves of violaxanthin de-epoxidation and fluorescence quenching and the short-term high-light pre-illumination experiments. An irregular down-regulation of the non-photochemical fluorescence quenching processes was observed, reflected by lower steady-state zeaxanthin and non-photochemical fluorescence quenching levels as compared with the corresponding non-treated high-light controls. It is concluded that light is essential not only for the initiation of the mechanism of resistance to Pq, but also for the penetration of Pq into the chloroplasts in the PqR E. canadensis. Also, the Pq elimination process may cause a modification to the regulation of the non-radiative energy dissipation in PqR plants in the presence of Pq.
Trehalose Induces the ADP-Glucose Pyrophosphorylase Gene,ApL3, and Starch Synthesis in Arabidopsis
Authors: Wingler Astrid , Fritzius Thorsten , Wiemken Andres , Boller Thomas , Aeschbacher Roger A.
Published: July 2002

In Arabidopsis, genes encoding functional enzymes for the synthesis and degradation of trehalose have been detected recently. In this study we analyzed how trehalose affects the metabolism and development of Arabidopsis seedlings. Exogenously applied trehalose (25 mm) strongly reduced the elongation of the roots and, concomitantly, induced a strong accumulation of starch in the shoots, whereas the contents of soluble sugars were not increased. When Arabidopsis seedlings were grown on trehalose plus sucrose (Suc), root elongation was restored, but starch still accumulated to a much larger extent than during growth on Suc alone. The accumulation of starch in the shoots of trehalose-treated seedlings was accompanied by an increased activity of ADP-glucose pyrophosphorylase and an induction of the expression of the ADP-glucose pyrophosphorylase gene,ApL3. Even in the presence of 50 mm Suc, which itself also slightly induced ApL3, trehalose (5 mm) led to a further increase in ApL3expression. These results suggest that trehalose interferes with carbon allocation to the sink tissues by inducing starch synthesis in the source tissues. Furthermore, trehalose induced the expression of the β-amylase gene, AT-β-Amy, in combination with Suc but not when trehalose was supplied alone, indicating that trehalose can modulate sugar-mediated gene expression.
Metabolic Modeling Identifies Key Constraints on an Engineered Glycine Betaine Synthesis Pathway in Tobacco
Authors: McNeil Scott D. , Rhodes David , Russell Brenda L. , Nuccio Michael L. , Shachar-Hill Yair , Hanson Andrew D.
Published: July 2002

Previous work has shown that tobacco (Nicotiana tabacum) plants engineered to express spinach choline monooxygenase in the chloroplast accumulate very little glycine betaine (GlyBet) unless supplied with choline (Cho). We therefore used metabolic modeling in conjunction with [14C]Cho labeling experiments and in vivo 31P NMR analyses to define the constraints on GlyBet synthesis, and hence the processes likely to require further engineering. The [14C]Cho doses used were large enough to markedly perturb Cho and phosphocholine pool sizes, which enabled development and testing of models with rates dynamically responsive to pool sizes, permitting estimation of the kinetic properties of Cho metabolism enzymes and transport systems in vivo. This revealed that import of Cho into the chloroplast is a major constraint on GlyBet synthesis, the import rate being approximately 100-fold lower than the rates of Cho phosphorylation and transport into the vacuole, with which import competes. Simulation studies suggested that, were the chloroplast transport limitation corrected, additional engineering interventions would still be needed to achieve levels of GlyBet as high as those in plants that accumulate GlyBet naturally. This study reveals the rigidity of the Cho metabolism network and illustrates how computer modeling can help guide rational metabolic engineering design.
Characterization of the 9-Cis-Epoxycarotenoid Dioxygenase Gene Family and the Regulation of Abscisic Acid Biosynthesis in Avocado
Authors: Chernys Jacqueline T. , Zeevaart Jan A.D.
Published: July 2002

Avocado (Persea americana Mill. cv Lula) is a climacteric fruit that exhibits a rise in ethylene as the fruit ripens. This rise in ethylene is followed by an increase in abscisic acid (ABA), with the highest level occurring just after the peak in ethylene production. ABA is synthesized from the cleavage of carotenoid precursors. The cleavage of carotenoid precursors produces xanthoxin, which can subsequently be converted into ABA via ABA-aldehyde. Indirect evidence indicates that the cleavage reaction, catalyzed by 9-cis-epoxycarotenoid dioxygenase (NCED), is the regulatory step in ABA synthesis. Three genes encoding NCED cleavage-like enzymes were cloned from avocado fruit. Two genes, PaNCED1 andPaNCED3, were strongly induced as the fruit ripened. The other gene, PaNCED2, was constitutively expressed during fruit ripening, as well as in leaves. This gene lacks a predicted chloroplast transit peptide. It is therefore unlikely to be involved in ABA biosynthesis. PaNCED1 was induced by water stress, but expression of PaNCED3 was not detectable in dehydrated leaves. Recombinant PaNCED1 and PaNCED3 were capable of in vitro cleavage of 9-cis-xanthophylls into xanthoxin and C25-apocarotenoids, but PaNCED2 was not. Taken together, the results indicate that ABA biosynthesis in avocado is regulated at the level of carotenoid cleavage.
Impact of Post-Anoxia Stress on Membrane Lipids of Anoxia-Pretreated Potato Cells. A Re-Appraisal
Authors: Pavelic Danijela , Arpagaus Silvio , Rawyler André , Brändle Roland
Published: July 2002

The importance of lipid peroxidation and its contributing pathways (via reactive oxygen species and lipoxygenase) during post-anoxia was evaluated with respect to the biphasic behavior of membrane lipids under anoxia (A. Rawyler, D. Pavelic, C. Gianinazzi, J. Oberson, R. Brändle [1999] Plant Physiol 120: 293–300), using potato (Solanum tuberosum cv Bintje) cell cultures. When anoxic cells in the pre-lytic phase were re-oxygenated for 2 h, superoxide anion was not detectable, the hydrogen peroxide (H2O2) level remained small and similar to that of controls, and cell viability was preserved. Lipids were intact and no lipid hydroperoxides were detected. However, small amounts of lipid hydroperoxides accumulated upon feeding anoxic cells with H2O2 and incubation for an additional 2 h under anoxia. When cells that entered the lytic phase of anoxia were re-oxygenated for 2 h, the H2O2 and superoxide anion levels were essentially unchanged. However, cell respiration decreased, reflecting the extensive lipid hydrolysis that had already started under anoxia and continued during post-anoxia. Simultaneous with the massive release of free polyunsaturated fatty acids, small amounts of lipid hydroperoxides were formed, reaching 1% to 2% of total fatty acids. Catalase and superoxide dismutase activities were not greatly affected, whereas the amount and activity of lipoxygenase tended to increase during anoxia. Lipid peroxidation in potato cells is therefore low during post-anoxia. It is mainly due to lipoxygenase, whereas the contribution of reactive oxygen species is negligible. But above all, it is a late event that occurs only when irreversible damage is already caused by the anoxia-triggered lipid hydrolysis.
The rib1 Mutant Is Resistant to Indole-3-Butyric Acid, an Endogenous Auxin in Arabidopsis
Authors: Poupart Julie , Waddell Candace S.
Published: July 2002

The presence of indole-3-butyric acid (IBA) as an endogenous auxin in Arabidopsis has been recently demonstrated. However, the in vivo role of IBA remains to be elucidated. We present the characterization of a semi-dominant mutant that is affected in its response to IBA, but shows a wild-type response to indole-3-acetic acid (IAA), the predominant and most studied form of auxin. We have named this mutantrib1 for resistant to IBA. Root elongation assays show that rib1 is specifically resistant to IBA, to the synthetic auxin 2,4-dichlorophenoxyacetic acid, and to auxin transport inhibitors. rib1 does not display increased resistance to IAA, to the synthetic auxin naphthalene acetic acid, or to other classes of plant hormones. rib1individuals also have other root specific phenotypes including a shortened primary root, an increased number of lateral roots, and a more variable response than wild type to a change in gravitational vector. Adult rib1 plants are morphologically indistinguishable from wild-type plants. These phenotypes suggest thatrib1 alters IBA activity in the root, thereby affecting root development and response to environmental stimuli. We propose models in which RIB1 has a function in either IBA transport or response. Our experiments also suggest that IBA does not use the same mechanism to exit cells as does IAA and we propose a model for IBA transport.
Analysis of Phosphate Acquisition Efficiency in Different Arabidopsis Accessions
Authors: Narang Ram A. , Bruene Asja , Altmann Thomas
Published: July 2002

The morphological and physiological characteristics of Arabidopsis accessions differing in their phosphate acquisition efficiencies (PAEs) when grown on a sparingly soluble phosphate source (hydroxylapatite) were analyzed. A set of 36 accessions was subjected to an initial PAE evaluation following cultivation on synthetic, agarose-solidified media containing potassium phosphate (soluble) or hydroxylapatite (sparingly soluble). From the five most divergent accessions identified in this way, C24, Co, and Calexhibited high PAEs, whereas Col-0 and Teexhibited low PAEs. These five accessions were analyzed in detail. Significant differences were found in root morphology, phosphate uptake kinetics, organic acid release, rhizosphere acidification, and the ability of roots to penetrate substrates. Long root hairs at high densities, high uptake per unit root length, and high substrate penetration ability in the efficient accessions C24 andCo mediate their high PAEs. The third accession with high PAE, Cal, exhibits a high shoot-to-root ratio, long roots with long root hairs, and rhizosphere acidification. These results are consistent with previous observations and highlight the suitability of using Arabidopsis accessions to identify and isolate genes determining the PAE in plants.
Evidence for the Involvement of an Oxidative Stress in the Initiation of Infection of Pear by Erwinia amylovora
Authors: Venisse Jean-Stéphane , Gullner Gabor , Brisset Marie-Noëlle
Published: July 2002

Involvement of an oxidative burst, usually related to incompatible plant/pathogen interactions leading to hypersensitive reactions, was investigated with Erwinia amylovora, the causal agent of fire blight of Maloideae subfamily of Rosaceae, in interaction with pear (Pyrus communis; compatible situation) and tobacco (Nicotiana tabacum; incompatible situation). As expected, this necrogenic bacterium induced in tobacco a sustained production of superoxide anion, lipid peroxidation, electrolyte leakage, and concomitant increases of several antioxidative enzymes (ascorbate peroxidases, glutathion reductases, glutathion-S-transferases, and peroxidases), in contrast to the compatible pathogen Pseudomonas syringae pvtabaci, which did not cause such reactions. In pear leaves, however, inoculations with both the disease- and the hypersensitive reaction-inducing bacteria (E. amylovoraand P. syringae pv tabaci, respectively) resulted in superoxide accumulation, lipid peroxidation, electrolyte leakage, and enzyme induction at similar rates and according to equivalent time courses. The unexpected ability of E. amylovora to generate an oxidative stress even in compatible situation was linked to its functional hrp (for hypersensitive reaction and pathogenicity) cluster because an Hrp secretion mutant of the bacteria did not induce any plant response. It is suggested that E. amylovora uses the production of reactive oxygen species as a tool to provoke host cell death during pathogenesis to invade plant tissues. The bacterial exopolysaccharide could protect this pathogen against the toxic effects of oxygen species since a non-capsular mutant of E. amylovora induced locally the same responses than the wild type but was unable to further colonize the plant.
Molecular Interactions between the Specialist HerbivoreManduca sexta (Lepidoptera, Sphingidae) and Its Natural Host Nicotiana attenuata. IV. Insect-Induced Ethylene Reduces Jasmonate-Induced Nicotine Accumulation by Regulating Putrescine N-Methyltransferase Transcripts,
Authors: Winz Robert A. , Baldwin Ian T.
Published: July 2002

Attack by the specialist herbivore, Manduca sexta, on its native host Nicotiana attenuata Torr. ex Wats. produces a dramatic ethylene release, a jasmonate burst, and a suppression of the nicotine accumulation that results from careful simulations of the herbivore's damage. Methyl-jasmonate (MeJA) treatment induces nicotine biosynthesis. However, this induction can be suppressed by ethylene as pretreatment of plants with 1-methylcyclopropene (1-MCP), a competitive inhibitor of ethylene receptors, restores the full MeJA-induced nicotine response in herbivore attacked plants (J. Kahl, D.H. Siemens, R.J. Aerts, R. Gäbler, F. Kühnemann, C.A. Preston, I.T. Baldwin [2000] Planta 210: 336–342). To understand whether this herbivore-induced signal cross-talk occurs at the level of transcript accumulation, we cloned the putrescine methyltransferase genes (NaPMT1 and NaPMT2) ofN. attenuata, which are thought to represent the rate limiting step in nicotine biosynthesis, and measured transcript accumulations by northern analysis after various jasmonate, 1-MCP, ethephon, and herbivory treatments. Transcripts of both root putrescineN-methyltransferase (PMT) genes and nicotine accumulation increased dramatically within 10 h of shoot MeJA treatment and immediately after root treatments. Root ethephon treatments suppressed this response, which could be reversed by 1-MCP pretreatment. Moreover, 1-MCP pretreatment dramatically amplified the transcript accumulation resulting from both wounding and M. sexta herbivory. We conclude that attack from this nicotine-tolerant specialist insect causes N. attenuatato produce ethylene, which directly suppresses the nitrogen-intensive biosynthesis of nicotine.
Phytochrome-Mediated Photoperiod Perception, Shoot Growth, Glutamine, Calcium, and Protein Phosphorylation Influence the Activity of the Poplar Bark Storage Protein Gene Promoter (bspA)
Authors: Zhu Baolong , Coleman Gary D.
Published: July 2002

In poplars (Populus), bspA encodes a 32-kD bark storage protein that accumulates in the inner bark of plants exposed to either short-day (SD) photoperiods or elevated levels of nitrogen. In this study, poplars transformed with a chimeric gene consisting of the bspA promoter fused to β-glucuronidase (uidA) were used to investigate the transcriptional regulation of the bspA promoter. Photoperiodic activation of the bspA promoter was shown to involve perception by phytochrome and likely involves both a low fluence response and a parallel very low fluence response pathway. Activity of the bspA promoter was also influenced by shoot growth. High levels of bspA expression usually occur in the bark of plants during SD but not long day orSD with a night break. When growth was inhibited under growth permissive photoperiods (SD with night break) levels of bark β-glucuronidase (GUS) activity increased. Stimulating shoot growth in plants treated with SD inhibited SD-induced increases in bark GUS activity. Because changes in photoperiod and growth also alter carbon and nitrogen partitioning, the role of carbon and nitrogen metabolites in modulating the activity of thebspA promoter were investigated by treating excised stems with amino acids or NH4NO3 with or without sucrose. Treatment with either glutamine or NH4NO3 resulted in increased stem GUS activity. The addition of sucrose with either glutamine or NH4NO3 resulted in synergistic induction of GUS, whereas sucrose alone had no effect. Glutamine plus sucrose induction of GUS activity was inhibited by EGTA, okadaic acid, or K-252A. Inhibition by EGTA was partially relieved by the addition of Ca2+. The Ca2+ ionophore, ionomycin, also induced GUS activity in excised shoots. These results indicate that transcriptional activation of bspA is complex. It is likely that SD activation of bspA involves perception by phytochrome coupled to changes in growth. These growth changes may then alter carbon and nitrogen partitioning that somehow signals bspA induction by a yet undefined mechanism that involves carbon and nitrogen metabolites, Ca2+, and protein phosphorylation/dephosphorylation.
Fatty Acid Synthesis in Pea Root Plastids Is Inhibited by the Action of Long-Chain Acyl- Coenzyme As on Metabolite Transporters
Authors: Fox Simon R. , Rawsthorne Stephen , Hills Matthew J.
Published: July 2002

The uptake in vitro of glucose (Glc)-6-phosphate (Glc-6-P) into plastids from the roots of 10- to 14-d-old pea (Pisum sativum L. cv Puget) plants was inhibited by oleoyl-coenzyme A (CoA) concentrations in the low micromolar range (1–2 μm). The IC50 (the concentration of inhibitor that reduces enzyme activity by 50%) for the inhibition of Glc-6-P uptake was approximately 750 nm; inhibition was reversed by recombinant rapeseed (Brassica napus) acyl-CoA binding protein. In the presence of ATP (3 mm) and CoASH (coenzyme A; 0.3 mm), Glc-6-P uptake was inhibited by 60%, due to long-chain acyl-CoA synthesis, presumably from endogenous sources of fatty acids present in the preparations. Addition of oleoyl-CoA (1 μm) decreased carbon flux from Glc-6-P into the synthesis of starch and through the oxidative pentose phosphate (OPP) pathway by up to 73% and 40%, respectively. The incorporation of carbon from Glc-6-P into fatty acids was not detected under any conditions. Oleoyl-CoA inhibited the incorporation of acetate into fatty acids by 67%, a decrease similar to that when ATP was excluded from incubations. The oleoyl-CoA-dependent inhibition of fatty acid synthesis was attributable to a direct inhibition of the adenine nucleotide translocator by oleoyl-CoA, which indirectly reduced fatty acid synthesis by ATP deprivation. The Glc-6-P-dependent stimulation of acetate incorporation into fatty acids was reversed by the addition of oleoyl-CoA.
Convenience food: space and timing
Authors: Warde Alan
Published: July 2002

This paper argues that the emergence of convenience food reflects the re‐ordering of the time‐space relations of everyday life in contemporary society. It is suggested that the notion of convenience food is highly contested. Britons are ambivalent about serving and eating convenience food. However, many people are constrained to eat what they call convenience foods as a provisional response to intransigent problems of scheduling everyday life. A distinction is drawn between modern and hypermodern forms of convenience, the first directed towards labour‐saving or time compression, the second to time‐shifting. It is maintained that convenience food is as much a hypermodern response to de‐routinisation as it is a modern search for the reduction of toil. Convenience food is required because people are too often in the wrong place; the impulse to time‐shifting arises from the compulsion to plan ever more complex time‐space paths in everyday life. The problem of timing supersedes the problem of shortage of time. Some of the more general social implications of such a claim are explored.
Success factors in learning organizations: an empirical study
Authors: Gardiner Penny , Whiting Peter
Published: July 2002

The learning organization may be the key to future success for organizations. There is no blueprint for success, but companies need to recognize and utilize the experience and expertise of their employees. In return, they must provide appropriate rewards and generate an environment of mutual trust and openness. A significant factor in this is the sharing of information. Attempts to assess learning organization characteristics in an engineering company using a specially developed questionnaire. Presents findings using eight conceptual groups. The company could not claim to have become a learning organization, though it had moved in this direction. Empowerment and employees’ self‐development were the areas where the company had developed most. Progress appeared to have been impeded by lack of change in other departments and by failure to share information throughout the company. This, in turn, had precluded the growth of trust between management and other employees.
Conventional two‐stroke engine lubrication
Authors: Wilson Bill
Published: July 2002

Gives the results of trials conducted in China which show the use of top‐grade, low smoke, part synthetic two‐stroke oil gives better performance and four times longer engine life than the four‐stroke engine oils generally used to lubricate two‐stroke engines in China. Sets out existing and proposed international standards for two‐stroke engine oils.
Testing bench for laser triangulation sensors
Authors: Keferstein Claus P. , Marxer Michael
Published: July 2002

Laser triangulation is a very efficient non‐contact point‐measurement procedure, very similar to a mechanical gauge, but much faster. However, the special characteristics of the laser triangulation sensor (LTS) must be taken into account for its use. The correct selection of sensor and test‐equipment verification, complying with norm ISO 9001, can be facilitated or implemented with the test‐bench for LTS, developed in the quality and production measurement technology laboratory of the Neu‐Technikum Buchs, Switzerland. A wide range of LTSs has been collated in a market analysis; differences of performance have been determined in a widespread comparison.
Numerical simulation of multi‐blow forging processes using the explicit time integration finite element method
Authors: Yoo Y.H. , Yang D.Y. , Chung D.T.
Published: July 2002

Describes simulations of impact forging processes. Uses the explicit time integration finite element method, which is based on direct time integration of equation of motion, to compute the deformation of the workpiece and the dies. Uses the program developed to simulate the copper blow test performed on a 350,000J counter‐blow hammer. The calculated result reveals a good agreement in the final deformed configurations between the experiment and the explicit simulation. In order to compare this with the explicit method, the implicit time integration rigid‐plastic finite element program considering the inertia effect is also applied to the copper blow test simulation. As a result of the copper blow test simulation using the explicit program and the implicit program, finds that the calculated results have good agreements in available plastic deformation energy, forging load and equivalent plastic strain distribution. Finally, applies the developed program to simulations of multi‐blow forging processes. Presents three major findings from the multi‐blow forging simulations: (1) the continuous analysis technique used for the multi‐blow forging simulations works well; (2) the blow efficiency and the forging load generated by blow operations can be analysed efficiently and simulated results coincide with previous experimental and analytical ones; (3) the geometrical configuration of the workpiece is closely related to blow efficiency.
Congruence of domestic and export marketing strategies ‐ An empirical investigation of its performance implications
Authors: Stewart David B. , McAuley Andrew
Published: July 2002

Discusses the concept of strategic composites, based upon the linkage of domestic and export marketing strategies of small, medium sized manufacturing firms. Four distinct composites are derived empirically for each of two national groups of exporters (Canadian and UK firms). With some minor variations, three particular composites are shown to be common to both Canadian and UK exporters. Concludes by examining the association between the export environment and the selected composite, and the effect that this has upon export performance.
Level 4 N/SVQs in Training and Development 1992‐1994
Authors: Canning Roy
Published: July 2002

The take‐up and completion rates for the level 4 N/SVQs in training and development over the period 1992‐1994 have been extremely disappointing. If these figures are representative of other higher level N/SVQs, then this gives major cause for concern over the proposed extension of the NVQ framework at higher levels. Argues that there is an urgent need for research into the take‐up and completion rates for other level 4 and 5 awards. Finally, a major obstacle to improving the quality of N/SVQ provision is the lack of data available at award level in England and Wales to determine the success or otherwise of particular NVQs . In Scotland the position is even more serious as no data are published on the performance of SVQs at framework or award level.
The Japanese distribution system
Authors: Martin Drew , Howard Carol , Herbig Paul
Published: July 2002

We review the Japanese distribution system, its positives and negatives, its cultural heritage, and discuss the implications for the future for it.
How do students spend their time?
Authors: Innis Karen , Shaw Malcolm
Published: July 2002

Describes the development, management and organization of a major cross‐university project designed to discover how students spend their study‐related time. Identifies critical strategic decisions both in diary instrumentation design and implementation and points out matters of general principle that might usefully inform similar ventures in other contexts and settings. Outlines a range of important results and gives some indication of the major implications that these findings have in the broader university context.
Government financial strategy in UK higher education: the relationships between quality, quantity and efficiency
Authors: Ghosh Deb , Rodgers Timothy
Published: July 2002

The reformers of the UK higher education system hoped that radical reform would simultaneously result in: improvements in the quality of education provided, increases in cost efficiency and a significant expansion in student numbers. This paper takes a close look at the reforms by undertaking both a time‐series and a cross‐section econometric analysis of the data to examine the relationships between quality, quantity and efficiency. Claims that the evidence shows that there have been genuine efficiency improvements and that these can be explained by the mechanics of the principal‐agent relationship which exists between the taxpayer and the higher education sector. However, it is also found that educational quality is costly, for example it is likely to cost the taxpayer £1,200 per academic per year to gain one percentage point in the production of first‐class graduates.
A breakthrough thinking organization
Authors: Chandon William , Nadler Gerald
Published: July 2002

In this article, the authors provide a practical framework for the development and implementation of successful organizational change programs. To date the focus of much writing in this area has been on “external” elements of organization but the authors argue that what is needed is more dialog in the “internal” elements (what goes on inside people’s heads). We suggest a framework, which guides change agent practitioners in the implementation of change in complex and dynamic business environments. We also discuss a framework for leaders and change practitioners to use to help build change agent capability. We argue that if you want to make change happen in an organization, you need to first change the questions you are asking yourself and the organization. Different questions lead to different actions and different results.
Assessing the cost‐effectiveness of integrated passives
Authors: Scheffler Michael , Tröster Gerhard , Lopez Contreras Joaquin , Hartung Jürgen , Menard Michel
Published: July 2002

Passive components integrated into a high‐density substrate can be a tolerable way to overcome the size and manufacturing limits of SMD passives mounted on to the system board. Still, this technology is perceived as being “too risky” and not cost‐effective. In this paper we propose a “passive optimized” solution combining the advantages from both SMD and integrated technology and avoiding the respective drawbacks. Exemplified by a GPS receiver front end, we present a methodology to assess the possible benefits when using the mixed technology.
Globalization, integration and commercial property. Evidence from the UK
Authors: McAllister Patrick
Published: July 2002

This paper analyses trends in direct international property investment by British investing institutions in the 1980s and 1990s. Although it is well established that there is home country bias in all investment sectors, evidence is presented which suggests that it is more pronounced in the direct property sector. The main focus is on barriers to international property investment and, therefore, potential sources of segmentation in the property sector. The research addresses a number of issues relating to levels of international property investment, the linkages between the nature of the core business and investment strategies and the relative importance of high diversification costs. This is carried out by an analysis of the most recent data on British institutional investment trends and by a survey questionnaire of British property professionals involved in asset allocation decisions for the investing institutions. The results indicate that: information costs are the most important barrier to international direct property investment, the high cost of executing a global diversification strategy inhibits international property investment, and institutions who have clients and see business opportunities in international centres are more likely to be interested in international property investment opportunities. The data on asset allocation trends support the view that the property market is significantly less integrated than the other securities markets.
BetaCore, a designed water soluble four‐stranded antiparallel β‐sheet protein
Authors: Carulla Natàlia , Woodward Clare , Barany George
Published: July 2002

BetaCore is a designed ∼50‐residue protein in which two BPTI‐derived core modules, CMIand CMII, are connected by a 22‐atom cross‐link. At low temperature and pH 3, homo‐ and heteronuclear NMR data report a dominant folded (′f') conformation with well‐dispersed chemical shifts,i, i+1 periodicity, numerous long‐range NOEs, and slowed amide hydrogen isotope exchange patterns that is a four‐stranded antiparallel β‐sheet with nonsymmetrical and specific association of CMIand CMII. BetaCore 'f' conformations undergo reversible, global, moderately cooperative, non‐two‐state thermal transitions to an equilibrium ensemble of unfolded 'u' conformations. There is a significant energy barrier between 'f' and 'u' conformations. This is the first designed four‐stranded antiparallel β‐sheet that folds in water.
Steady-State Limit of Elastoplastic Trusses for the Plastic Shakedown Region
Authors: Uetani K. , Araki Y.
Published: July 2002

For elastoplastic trusses under quasi-static cyclic loading, a method is presented for finding the steady-state limit that bounds the plastic shakedown and ratchetting regions. In the plastic shakedown region, an assumption employed in the previous approaches for finding the steady-state limit can be invalid in many circumstances. Although strain reversals were assumed to occur only at load reversals, yielding of an element exhibiting plastic shakedown may cause strain reversals in other elements. This difficulty is overcome by relaxing this assumption so that the strain reversals due to yielding are taken into account. Numerical examples showed that the present method can find the steady-state limit even when strong effects of geometrical nonlinearity exist. [S0021-8936(00)01201-0]
Finding Minimum Cost Tool Grouping Schemes on Machining Systems
Authors: Yip-Hoi Derek , Dutta Debasish
Published: July 2002

Changing worn tools is a major concern in planning operations on machining systems. Strategies for replacing tools range from changing each tool as it reaches its projected tool life, to changing all tools when the tool with the shortest life on the machining system is expended. Intermediate strategies involve changing tools in groups. Each of these strategies has two cost components associated with it: (1) the cost of lost production due to machine tool stoppage, and (2) the cost of unused tool life. The best tool grouping strategy minimizes the combined cost of lost production. In this paper we present an approach for finding good tool grouping strategies from inputs that include the tool utilization for a given machining application, and the tooling and machining system costs. A genetic algorithm is used as the underlying optimization paradigm for finding the minimum cost strategy. An example is presented for a part produced on a machining center. [S1087-1357(00)00303-8]
Hemolytic Potential of Hydrodynamic Cavitation
Authors: Chambers Sean D. , Bartlett Robert H. , Ceccio Steven L.
Published: July 2002

The purpose of this study was to determine the hemolytic potentials of discrete bubble cavitation and attached cavitation. To generate controlled cavitation events, a venturi-geometry hydrodynamic device, called a Cavitation Susceptibility Meter (CSM), was constructed. A comparison between the hemolytic potential of discrete bubble cavitation and attached cavitation was investigated with a single-pass flow apparatus and a recirculating flow apparatus, both utilizing the CSM. An analytical model, based on spherical bubble dynamics, was developed for predicting the hemolysis caused by discrete bubble cavitation. Experimentally, discrete bubble cavitation did not correlate with a measurable increase in plasma-free hemoglobin (PFHb), as predicted by the analytical model. However, attached cavitation did result in significant PFHb generation. The rate of PFHb generation scaled inversely with the Cavitation number at a constant flow rate, suggesting that the size of the attached cavity was the dominant hemolytic factor. [S0148-0731(00)00404-0]
Development of a Fuzzy-Neuro System for Parameter Resetting of Injection Molding
Authors: He W. , Zhang Y. F. , Lee K. S. , Liu T. I.
Published: July 2002

An intelligent system has been used for injection molding. Five molded part defects, two mold parameters and the part weight are used as system inputs which are described by fuzzy terms. Twenty process parameter adjusters on an injection molding machine are used as the outputs. A neural network has been trained using the data obtained from test-runs of injection molding. The intelligent system can predict the amount to be adjusted for each parameter towards reducing or eliminating the observed defects. Using this system for the parameter resetting, production time and efforts can be saved drastically. Feasibility studies showed that this intelligent system is capable of reducing the test run time by at least 80 percent.
Falling Film and Spray Evaporation Enhancement Using an Applied Electric Field
Authors: Darabi J. , Ohadi M. M. , Desiatoun S. V.
Published: July 2002

The effect of an electric field on the falling-film evaporation of refrigerant R-134a on a vertical plate and three commercially available tubes was investigated experimentally. The plate test section was 25.4 mm wide and 76.2 mm long, and each tube test section was 19 mm in diameter and 140 mm long. Experiments were conducted in both falling film and spray evaporation modes. The effects of various parameters such as heat flux, refrigerant flow rate, electrode gap, and applied voltage were investigated. It was found that in the presence of an applied electric field, the maximum enhancement in the heat transfer coefficient for both falling film and spray evaporation modes on a plate was nearly the same. A maximum enhancement of fourfold in the heat transfer coefficient with the plate, 90 percent with the smooth tube, 110 percent with the Turbo BIII, and 30 percent with 19 fpi tube were obtained. The electrohydrodynamic power consumption in all cases was less than 0.12 percent of the total energy exchange rate in the test section. [S0022-1481(00)03003-6]
On the Optimal Damping of a Vibrating Shape Memory Alloy Rod
Authors: Oberaigner Eduard R. , Fischer Franz D. , Tanaka Kikuaki
Published: July 2002

Vibration damping through phase transformation is one major area of application of shape memory alloys in smart systems and structures. The authors of this study have shown in earlier publications, how damping of vibrating rods can be accomplished. This paper is an extension and generalization. On the one side it uses the proper description of the stress-wave phenomenon instead of a quasi-static approximation, on the other side it describes, how the damping could be optimized. The basic equations of the underlying mathematical model are the stress-wave equation, the heat conduction equation, a kinetic and a constitutive law as well as a condition to ensure maximal damping. The major results are the heating history, which governs the phase transformation, and the domain splitting along the rod into elastic and inelastic regions.
Heat Transfer and Flow on the Squealer Tip of a Gas Turbine Blade
Authors: Azad Gm. S. , Han Je-Chin , Boyle Robert J.
Published: July 2002

Experimental investigations are performed to measure the detailed heat transfer coefficient and static pressure distributions on the squealer tip of a gas turbine blade in a five-bladed stationary linear cascade. The blade is a two-dimensional model of a modern first-stage gas turbine rotor blade with a blade tip profile of a GE-E3 aircraft gas turbine engine rotor blade. A squealer (recessed) tip with a 3.77 percent recess is considered here. The data on the squealer tip are also compared with a flat tip case. All measurements are made at three different tip gap clearances of about 1, 1.5, and 2.5 percent of the blade span. Two different turbulence intensities of 6.1 and 9.7 percent at the cascade inlet are also considered for heat transfer measurements. Static pressure measurements are made in the midspan and near-tip regions, as well as on the shroud surface opposite to the blade tip surface. The flow condition in the test cascade corresponds to an overall pressure ratio of 1.32 and an exit Reynolds number based on the axial chord of 1.1×106. A transient liquid crystal technique is used to measure the heat transfer coefficients. Results show that the heat transfer coefficient on the cavity surface and rim increases with an increase in tip clearance. The heat transfer coefficient on the rim is higher than the cavity surface. The cavity surface has a higher heat transfer coefficient near the leading edge region than the trailing edge region. The heat transfer coefficient on the pressure side rim and trailing edge region is higher at a higher turbulence intensity level of 9.7 over 6.1 percent case. However, no significant difference in local heat transfer coefficient is observed inside the cavity and the suction side rim for the two turbulence intensities. The squealer tip blade provides a lower overall heat transfer coefficient when compared to the flat tip blade. [S0889-504X(00)00504-3]
Thermal Diffusivity Mapping of Friction Surface Using Photo-Thermal Technique
Authors: Teo Kia-Moh , Lafdi Khalid
Published: July 2002

In this paper, both theory and experimental setup of the photo-thermal technique are presented. Based on this technique, two measurement methodologies are available: phase shift method and temperature change method. However, only the experimental results from the phase shift method are presented in this paper. The measurements can be performed at any radial direction on a sample’s surface. This technique appears to be a successful method for measuring the variation of surface thermal diffusivity of various materials. An automated platform has also been developed and integrated into the technique to measure and map the variation of surface thermal diffusivity of a material. This technique can be used to detect any surface’s thermal defects of a material. It is also useful in studying the surface temperature distribution of a heat application material. One of its applications is on the study of friction. The temperature increase of a friction material subjected to a sliding process is influenced by its thermal property at the sliding interface. The thermal diffusivity mapping of a rubbing surface may help in predicting its surface temperature distribution and in studying the thermal behavior of a friction interface.
Influence of Imperfections in Working Media on Diesel Engine Indicator Process
Authors: Danov S. N. , Gupta A. K.
Published: July 2002

Several improvements to the mathematical model for the indicator process in a diesel engine cylinder are proposed. The thermodynamic behavior of working media is described by the equation of state valid for real gases. Analytical mathematical dependencies between thermal parameters (pressure, temperature, volume) and caloric parameters (internal energy, enthalpy, specific heat capacities) have been obtained. These equations have been applied to the various products encountered during the burning of fuel and the gas mixture as a whole in the engine cylinder under conditions of high pressures. An improved mathematical model, based on the first law of thermodynamics, has been developed by taking into account imperfections in the working media that appear under high pressures. The numerical solution of the simultaneous differential equations is obtained by Runge–Kutta-type method. The mathematical model is then used to solve the desired practical problems in two different two-stroke turbo-charged engines: 8DKRN 74/160 and Sulzer-RLB66. Significant differences between the values calculated using ideal gas behavior and the real gas at high-pressure conditions have been found. The numerical experiments show that if the pressure is above 8 to 9 MPa, the imperfections in working medium must be taken into consideration. The results obtained from the mathematical dependencies of the caloric parameters can also be used to model energy conversion and combustion processes in other thermal machines such as advanced gas turbine engines with high-pressure ratios.
Experimental Investigation of 3-D Crack-Tip Deformation Using Moire´-Sagnac Interferometry
Authors: Kang B. S.-J. , Anderson S. M.
Published: July 2002

A combined moire´-Sagnac interferometry method was applied for in-plane and out-of- plane crack-tip surface deformation measurement. Based on 2-D and 3-D Jacobian derivative method (JDM), a stress intensity factor evaluation procedure is proposed. This procedure utilizes selected measured displacements around the crack-tip region as input nodal displacements to calculate the stress intensity factor and the results correlate well with the theoretical calculations. The extent of the 3-D crack-tip deformation zone is also discussed.