bluuebunny/crossref_metadata_2025 huggingface dataset:
Proteasome Inhibitors Prevent Tracheary Element Differentiation in Zinnia Mesophyll Cell Cultures
Authors: Woffenden Bonnie J. , Freeman Thomas B. , Beers Eric P.
Published: July 2002

To determine whether proteasome activity is required for tracheary element (TE) differentiation, the proteasome inhibitors clasto-lactacystin β-lactone and carbobenzoxy-leucinyl-leucinyl-leucinal (LLL) were used in a zinnia (Zinnia  elegans) mesophyll cell culture system. The addition of proteasome inhibitors at the time of culture initiation prevented differentiation otherwise detectable at 96 h. Inhibition of the proteasome at 48 h, after cellular commitment to differentiation, did not alter the final percentage of TEs compared with controls. However, proteasome inhibition at 48 h delayed the differentiation process by approximately 24 h, as indicated by examination of both morphological markers and the expression of putative autolytic proteases. These results indicate that proteasome function is required both for induction of TE differentiation and for progression of the TE program in committed cells. Treatment at 48 h with LLL but not clasto-lactacystin β-lactone resulted in partial uncoupling of autolysis from differentiation. Results from gel analysis of protease activity suggested that the observed incomplete autolysis was due to the ability of LLL to inhibit TE cysteine proteases.
A Gene Encoding Proline Dehydrogenase Is Not Only Induced by Proline and Hypoosmolarity, but Is Also Developmentally Regulated in the Reproductive Organs of Arabidopsis
Authors: Nakashima Kazuo , Satoh Rie , Kiyosue Tomohiro , Yamaguchi-Shinozaki Kazuko , Shinozaki Kazuo
Published: July 2002

The cDNA clone ERD5 (earlyresponsive to dehydration), isolated from 1-h-dehydrated Arabidopsis, encodes a precursor of proline (Pro) dehydrogenase (ProDH), which is a mitochondrial enzyme involved in the first step of the conversion of Pro to glutamic acid. The transcript of the erd5 (ProDH) gene was undetectable when plants were dehydrated, but large amounts of transcript accumulated when plants were subsequently rehydrated. Accumulation of the transcript was also observed in plants that had been incubated under hypoosmotic conditions in media that contained l- ord-Pro. We isolated a 1.4-kb DNA fragment of the putative promoter region of the ProDH gene. Theβ-glucuronidase (GUS) reporter gene driven by the 1.4-kb ProDH promoter was induced not only by rehydration but also by hypoosmolarity and l- andd-Pro at significant levels in transgenic Arabidopsis plants. The promoter of the ProDH gene directs strong GUS activity in reproductive organs such as pollen and pistils and in the seeds of the transgenic plants. GUS activity was detected in vegetative tissues such as veins of leaves and root tips when the transgenic plants were exposed to hypoosmolarity and Pro solutions. GUS activity increased during germination of the transgenic plants under hypoosmolarity. The relationship between Pro metabolism and the physiological aspects of stress response and development are discussed.
High-Molecular-Weight FK506-Binding Proteins Are Components of Heat-Shock Protein 90 Heterocomplexes in Wheat Germ Lysate
Authors: Reddy Ramachandra K. , Kurek Isaac , Silverstein Adam M. , Chinkers Michael , Breiman Adina , Krishna Priti
Published: July 2002

In animal cell lysates the multiprotein heat-shock protein 90 (hsp90)-based chaperone complexes consist of hsp70, hsp40, and p60. These complexes act to convert steroid hormone receptors to their steroid-binding state by assembling them into heterocomplexes with hsp90, p23, and one of several immunophilins. Wheat germ lysate also contains a hsp90-based chaperone system that can assemble the glucocorticoid receptor into a functional heterocomplex with hsp90. However, only two components of the heterocomplex-assembly system, hsp90 and hsp70, have thus far been identified. Recently, purified mammalian p23 preadsorbed with JJ3 antibody-protein A-Sepharose pellets was used to isolate a mammalian p23-wheat hsp90 heterocomplex from wheat germ lysate (J.K. Owens-Grillo, L.F. Stancato, K. Hoffmann, W.B. Pratt, and P. Krishna [1996] Biochemistry 35: 15249–15255). This heterocomplex was found to contain an immunophilin(s) of the FK506-binding class, as judged by binding of the radiolabeled immunosuppressant drug [3H]FK506 to the immune pellets in a specific manner. In the present study we identified the immunophilin components of this heterocomplex as FKBP73 and FKBP77, the two recently described high-molecular-weight FKBPs of wheat. In addition, we present evidence that the two FKBPs bind hsp90 via tetratricopeptide repeat domains. Our results demonstrate that binding of immunophilins to hsp90 via tetratricopeptide repeat domains is a conserved protein interaction in plants. Conservation of this protein-to-protein interaction in both plant and animal cells suggests that it is important for the biological action of the high-molecular-weight immunophilins.
Regulation of Soybean Nodulation Independent of Ethylene Signaling1
Authors: Schmidt J. Scott , Harper James E. , Hoffman Thomas K. , Bent Andrew F.
Published: July 2002

Leguminous plants regulate the number of Bradyrhizobium- or Rhizobium-infected sites that develop into nitrogen-fixing root nodules. Ethylene has been implicated in the regulation of nodule formation in some species, but this role has remained in question for soybean (Glycine max). The present study used soybean mutants with decreased responsiveness to ethylene, soybean mutants with defective regulation of nodule number, and Ag+ inhibition of ethylene perception to examine the role of ethylene in the regulation of nodule number. Nodule numbers on ethylene-insensitive mutants and plants treated with Ag+ were similar to those on wild-type plants and untreated plants, respectively. Hypernodulating mutants displayed wild-type ethylene sensitivity. Suppression of nodule numbers by high nitrate was also similar between ethylene-insensitive plants, wild-type plants, and plants treated with Ag+. Ethylene insensitivity of the roots of etr1-1 mutants was confirmed using assays for sensitivity to 1-aminocyclopropane-1-carboxylic acid and for ethylene-stimulated root-hair formation. Additional phenotypes ofetr1-1 roots were also characterized. Ethylene-dependent pathways regulate the number of nodules that form on species such as pea and Medicago truncatula, but our data indicate that ethylene is less significant in regulating the number of nodules that form on soybean.
Prediction of Protein Cleavage Sites by the Barley Cysteine Endoproteases EP-A and EP-B Based on the Kinetics of Synthetic Peptide Hydrolysis
Authors: Davy Anne , Sørensen Mikael Blom , Svendsen Ib , Cameron-Mills Verena , Simpson David J.
Published: July 2002

Hordeins, the natural substrates of barley (Hordeum vulgare) cysteine endoproteases (EPs), were isolated as protein bodies and degraded by purified EP-B from green barley malt. Cleavage specificity was determined by synthesizing internally quenched, fluorogenic tetrapeptide substrates of the general formula 2-aminobenzoyl-P2-P1-P1′-P2′ 1-tyrosine(NO2)-aspartate. The barley EPs preferred neutral amino acids with large aliphatic and nonpolar (leucine, valine, isoleucine, and methionine) or aromatic (phenylalanine, tyrosine, and tryptophan) side chains at P2, and showed less specificity at P1, although asparagine, aspartate, valine, and isoleucine were particularly unfavorable. Peptides with proline at P1 or P1′ were extremely poor substrates. Cleavage sites with EP-A and EP-B preferred substrate sequences are found in hordeins, their natural substrates. The substrate specificity of EP-B with synthetic peptides was used successfully to predict the cleavage sites in the C-terminal extension of barley β-amylase. When all of the primary cleavage sites in C hordein, which occur mainly in the N- and C-terminal domains, were removed by site-directed mutagenesis, the resulting protein was degraded 112 times more slowly than wild-type C hordein. We suggest that removal of the C hordein terminal domains is necessary for unfolding of the β-reverse turn helix of the central repeat domain, which then becomes more susceptible to proteolytic attack by EP-B.
Spatio-Temporal Accumulation and Activity of Calcium-Dependent Protein Kinases during Embryogenesis, Seed Development, and Germination in Sandalwood
Authors: Anil Veena S. , Harmon Alice C. , Rao K. Sankara
Published: July 2002

Western-blot analysis and protein kinase assays identified two Ca2+-dependent protein kinases (CDPKs) of 55 to 60 kD in soluble protein extracts of embryogenic cultures of sandalwood (Santalum album L.). However, these sandalwood CDPKs (swCDPKs) were absent in plantlets regenerated from somatic embryos. swCDPKs exhibited differential expression (monitored at the level of the protein) and activity in different developmental stages. Zygotic embryos, seedlings, and endosperm showed high accumulation of swCDPK, but the enzyme was not detected in the soluble proteins of shoots and flowers. swCDPK exhibited a temporal pattern of expression in endosperm, showing high accumulation and activity in mature fruit and germinating stages; the enzyme was localized strongly in the storage bodies of the endosperm cells. The study also reports for the first time to our knowledge a post-translational inhibition/inactivation of swCDPK in zygotic embryos during seed dormancy and early stages of germination. The temporal expression of swCDPK during somatic/zygotic embryogenesis, seed maturation, and germination suggests involvement of the enzyme in these developmental processes.
Ascorbate Biosynthesis in Mitochondria Is Linked to the Electron Transport Chain between Complexes III and IV
Authors: Bartoli Carlos G. , Pastori Gabriela M. , Foyer Christine H.
Published: July 2002

Ascorbic acid is synthesized from galactono-γ-lactone (GL) in plant tissues. An improved extraction procedure involving ammonium sulfate precipitation of membrane proteins from crude leaf homogenates yielded a simple, quick method for determining tissue activities of galactono-γ-lactone dehydrogenase (GLDH). Total foliar ascorbate and GLDH activity decreased with leaf age. Subcellular fractionation experiments using marker enzymes demonstrated that 80% of the total GLDH activity was located on the inner mitochondrial membrane, and 20% in the microsomal fraction. Specific antibody raised against potato (Solanum tuberosum  L.) tuber GLDH recognized a 56-kD polypeptide in extracts from the mitochondrial membranes but failed to detect the equivalent polypeptide in microsomes. We demonstrate that isolated intact mitochondria synthesize ascorbate in the presence of GL. GL stimulated mitochondrial electron transport rates. The respiration inhibitor antimycin A stimulated ascorbate biosynthesis, while cyanide inhibited both respiration and ascorbate production. GL-dependent oxygen uptake was observed in isolated intact mitochondria. This evidence suggests that GLDH delivers electrons to the mitochondrial electron transport chain between complexes III and IV.
Biochemical Characterization of Wild-Type and Mutant Isoamylases of Chlamydomonas reinhardtii Supports a Function of the Multimeric Enzyme Organization in Amylopectin Maturation
Authors: Dauvillée David , Colleoni Christophe , Mouille Gregory , Morell Matthew K. , d'Hulst Christophe , Wattebled Fabrice , Liénard Luc , Delvallé David , Ral Jean-Philippe , Myers Alan M. , Ball Steven G.
Published: July 2002

Chlamydomonas reinhardtii mutants of theSTA8 gene produce reduced amounts of high amylose starch and phytoglycogen. In contrast to the previously described phytoglycogen-producing mutants of C. reinhardtii that contain no residual isoamylase activity, the sta8mutants still contained 35% of the normal amount of enzyme activity. We have purified this residual isoamylase and compared it with the wild-type C. reinhardtii enzyme. We have found that the high-mass multimeric enzyme has reduced its average mass at least by one-half. This coincides with the disappearance of two out of the three activity bands that can be seen on zymogram gels. Wild-type and mutant enzymes are shown to be located within the plastid. In addition, they both act by cleaving off the outer branches of polysaccharides with no consistent difference in enzyme specificity. Because the mutant enzyme was demonstrated to digest phytoglycogen to completion in vitro, we propose that its inability to do so in vivo supports a function of the enzyme complex architecture in the processing of pre-amylopectin chains.
The Sucrose Analog Palatinose Leads to a Stimulation of Sucrose Degradation and Starch Synthesis When Supplied to Discs of Growing Potato Tubers
Authors: Fernie Alisdair R. , Roessner Ute , Geigenberger Peter
Published: July 2002

In the present paper we investigated the effect of the sucrose (Suc) analog palatinose on potato (Solanum tuberosum) tuber metabolism. In freshly cut discs of growing potato tubers, addition of 5 mm palatinose altered the metabolism of exogenously supplied [U-14C]Suc. There was slight inhibition of the rate of 14C-Suc uptake, a 1.5-fold increase in the rate at which 14C-Suc was subsequently metabolized, and a shift in the allocation of the metabolized label in favor of starch synthesis. The sum result of these changes was a 2-fold increase in the absolute rate of starch synthesis. The increased rate of starch synthesis was accompanied by a 3-fold increase in inorganic pyrophosphate, a 2-fold increase in UDP, decreased UTP/UDP, ATP/ADP, and ATP/AMP ratios, and decreased adenylate energy charge, whereas glycolytic and Krebs cycle intermediates were unchanged. In addition, feeding palatinose to potato discs also stimulated the metabolism of exogenous 14C-glucose in favor of starch synthesis. In vitro studies revealed that palatinose is not metabolized by Suc synthases or invertases within potato tuber extracts. Enzyme kinetics revealed different effects of palatinose on Suc synthase and invertase activities, implicating palatinose as an allosteric effector leading to an inhibition of Suc synthase and (surprisingly) to an activation of invertase in vitro. However, measurement of tissue palatinose levels revealed that these were too low to have significant effects on Suc degrading activities in vivo. These results suggest that supplying palatinose to potato tubers represents a novel way to increase starch synthesis.
The Delayed Terminal Flower Phenotype Is Caused by a Conditional Mutation in the CENTRORADIALIS Gene of Snapdragon
Authors: Cremer Frédéric , Lönnig Wolf-Ekkehard , Saedler Heinz , Huijser Peter
Published: July 2002

The snapdragon (Antirrhinum majus)centroradialis mutant (cen) is characterized by the development of a terminal flower, thereby replacing the normally open inflorescence by a closed inflorescence. In contrast to its Arabidopsis counterpart, terminal flower1, the cen-null mutant displays an almost constant number of lateral flowers below the terminal flower. Some partial revertants of an X-radiation-induced cen mutant showed a delayed formation of the terminal flower, resulting in a variable number of lateral flowers. The number of lateral flowers formed was shown to be environmentally controlled, with the fewer flowers formed under the stronger flower-inducing conditions. Plants displaying this “Delayed terminal flower” phenotype were found to be heterozygous for a mutant allele carrying a transposon in the coding region and an allele from which the transposon excised, leaving behind a 3-bp duplication as footprint. As a consequence, an iso-leucine is inserted between Asp148 and Gly149 in the CENTRORADIALIS protein. It is proposed that this mutation results in a low level of functional CEN activity, generating a phenotype that is more similar to the Arabidopsis Terminal flower phenotype.
The Boeing 777 fuel system
Authors: Ford Terry
Published: July 2002

Explains the fuel system of the Boeing 777‐200 aircraft. Looks at the system’s features, the fuel feed, the fuel jettison and the flight deck displays in terms of the fuel system.
An application of the stages of change model to consumer use of food labels
Authors: Coulson Neil S.
Published: July 2002

Describes a study which applied the stages of change model formulated by Prochaska and DiClemente to consumer use of food labels. A total of 165 students completed a self‐report questionnaire measuring stages of change, decisional balance, dietary behaviour and food choice motivations. The percentage of participants classified into each stage was as follows: precontemplation 30.0, contemplation 4.5, action 16.4 and maintenance 49.1. Significant associations with stage of change and decisional balance were observed. In addition, consumption of fruit and fatty foods was associated with stage of change as was a range of motivational factors in food choice.
The development of a European information society
Authors: Hoare Peter
Published: July 2002

The development of a society reliant on information is traced from the scientific revolutions of the mid‐seventeenth century. Throughout Europe (and later the world) this led to new methods of dissemination and control of published information, through libraries and other institutions, and more recently through the application of electronic technology. The term “information society” should not be restricted to an IT‐based culture: the roots are much deeper and the concept of information continues a long tradition.
Changing fortunes: changing food choices
Authors: Anderson Annie S. , Morris Susan E.
Published: July 2002

The Ministry of Agriculture, Fisheries and Food funded a two‐year project on “Constraints on freedom of dietary choice and their implications for the adoption and maintenance of healthy diets”. Part of this work included a study on the impact of changing income on dietary patterns, food intake and food preferences. Results suggest that alterations in food choices relevant to health promotion occur in people who have experienced a change in income although further study is necessary to explore the longer‐term results of these actions.
Five a day – challenges and achievements
Authors: Anderson Annie S. , Cox David
Published: July 2002

The Ministry of Agriculture, Fisheries and Food funded the project increasing vegetable and fruit consumption between 1994 and 1996. The project was carried out in three phases comprising a nationwide survey of attitudes towards increasing fruit and vegetable intake, a community‐based intervention trial and a workplace intervention trial. This paper reports qualitative data from focus group work with participants of the phase 2 community intervention describing some of the realities and challenges associated with achieving five a day in a free‐living setting.
A comparison of MTM and RTM
Authors: Choi C.K. , Ip W.H.
Published: July 2002

In recent years, high labour costs and the inconsistency of manual asembly have led to the wider acceptance of robotic assembly in product manufacturing. Planning robot assembly tasks requires a method of estimating robotic cycle time. Identifies some of the relationships between robot assembly time and manual assembly time, in order to develop a method of robot assembly time estimation based on manual assembly times. Uses methods time measurement (MTM) and robot time and motion (RTM) as the basis of comparison. Uses two case studies to evaluate the approach.
Supervisor and manager approaches to handling discipline and grievance: a follow‐up study
Authors: Rollinson Derek J.
Published: July 2002

This paper reports the results of a follow‐up study to two linked articles appearing in earlier issues of this journal. It examines the relative influence of factors affecting the approach of supervisors or managers to dealing with disciplinary or grievance incidents. For discipline the most influential factors are identified as: the inconvenience of the employee rule transgression and the length of an employee’s service, with comparatively minor effects for employee gender, manager gender, prior training and experience in handling issues, and whether an organization is unionised. With grievance the most influential factors are: the challenge to management authority of an issue, length of employee service, employee gender and to a lesser extent the age and gender of the manager, and whether the organization is unionised. Implications for future research and the training of supervisors and managers are then outlined.
Improving Library Personnel Management
Authors: Al‐Hassan Sulaiman , Meadows A.J.
Published: July 2002

An investigation of personnel management in Kuwaiti libraries prior to
the Gulf War showed that serious problems existed in most libraries.
Describes a further study which was therefore carried out to try to
define actions which might help to alleviate these problems. A
soft‐systems methodology was used for the first time in this context:
the approach seems generalizable to most situations involving library
personnel management. Subsequent discussion of the study with senior
library management in Kuwait was delayed by the advent of the Gulf War.
However, the changed conditions in Kuwait brought about by the war are
found to have imparted particular significance to the conclusions and to
their implementation.
In Search of Excellence in Libraries
Authors: Barter Richard F.
Published: July 2002

Examines the four books published by Tom Peters (In Search of
Excellence, A Passion for Excellence, Thriving on Chaos, and Liberation
Management), a major contemporary contributor to management thinking,
and relates these new approaches to the management of Library and
Information Services (LIS), using examples from Britain, North America,
and Australia. The main areas of enquiry (based on the
“prescriptions” from Thriving on Chaos) are the importance of
customer responsiveness, innovation, empowerment of people within the
LIS workforce, dynamic leadership, and appropriate systems.
A hybrid formulation in the stress analysis of curved pipes
Authors: Madureira Luísa , Melo Francisco Q.
Published: July 2002

Describes a hybrid formulation solution based on variational techniques, where unknown functions are combined with a set of Fourier trigonometric expansions. The unknown functions refer to the toroidal shell distortion in the longitudinal direction when the shell is submitted to generalised in‐plane forces in the linear‐elastic stress field. This set of functions is solved from a system of differential equations, having calculated the eigenvalues and corresponding eigenvectors in the complex field from the system equations matrix. For this purpose the MAPLE® mathematical solver was used. This module led to an analytical solution, which is exact for each Fourier term used in the global solution. The final results agree very well with finite element method or other solutions obtained using a total expansion of trigonometric functions in the longitudinal and meridional directions.
Some experiences of shape‐forming process: experiments and numerical simulations
Authors: Yoshida Shiro , Kihara Shigefumi
Published: July 2002

Proposes the particle model as an improved finite element method for the analysis of metal forming, particularly highlighting the forging process. Analyses the forged material in the present modelling in conjunction with non‐material domain, and expresses the process not by the finite element deformation, but by the “movable particle” which discriminates the material domain. This “fixed mesh” algorithm gives the capabilities treating metal forging problems easily. Demonstrates the effectiveness of the method using some applications.
A three‐dimensional finite element analysis of hot extrusion through square dies
Authors: Kang Y.S. , Yang D.Y.
Published: July 2002

Applies an updated Lagrangian finite element analysis with automatic remeshing scheme to three‐dimensional hot extrusion through landless square dies. The remeshing procedure is composed mainly with decision for remeshing, transfer of state variables and mesh generation. The procedure is carried out fully automatically. In the procedure, it is difficult to generate the mesh automatically, considering the physical characteristics. Accomplishes mesh generation by introducing the modular concept. The mesh generated by the modular concept has advantages, especially for three‐dimensional problems, such as economic computational time and consideration of physical characteristics. Classes the profiles of orifice into two cases; and develops the orifice adaptive module for each case and then carries out numerical examples by using the orifice adaptive modules.
The application of a diagnostic model and surveys in organizational development
Authors: Lok Peter , Crawford John
Published: July 2002

Examines the relationship between employees’ responses to the Organizational Diagnosis Questionnaire and ratings of organizational effectiveness in two organizations. Preziosi’s (1980) Organizational Diagnosis Questionnaire (ODQ), and Steele’s (1987) Organizational Effectiveness Questionnaire (OEQ), were distributed to employees in two Australian companies, and a total of 349 useable responses were obtained. Factor analysis of the ODQ yielded six meaningful factors which were interpreted in terms of the original sub‐scales of the ODQ as proposed by Preziosi. Factor analysis of the OEQ gave rise to two positively correlated effectiveness factors. Cronbach alpha reliability estimates were obtained for each of the original ODQ sub‐scales and for the six sub‐scales derived from the factor analysis of the questionnaire responses. Reliabilities for the two sets of sub‐scales were comparable, but with the factor‐based scales giving slightly higher reliabilities. Comparison of mean scores derived from the two organizations showed that significant differences existed for the organizational effectiveness measures, and for several of the measures derived from the ODQ. Regression analysis showed that the difference in the effectiveness rating of the two organizations can be partially explained in terms of the differences in responses to the ODQ.
Performance appraisal in public libraries
Authors: Harrison Karen , Goulding Anne
Published: July 2002

Examines the impact performance appraisal has had, and is having, on public libraries. Considers appraisal in a broader context, discussing the effect political opinions and decisions have had on the way appraisal has been introduced into the public sector. Discusses the theory of appraisal in relation to what happens in practice using evidence from a case study carried out as part of a BA Librarianship at Loughborough University. Considers the purpose of appraisal and how it should be carried out in order to maximize its potential for improving individual and organizational performance. Suggests that appraisal in public libraries has a tendency to fail because not enough attention is given to defining the aim of appraisal, to ensuring communication channels are open and that proposed training is followed through. The design of an appraisal system can also cause problems if the specific nature of library work is not considered. Concludes that the external political and economic environment has significant implications that can make implementation of an appraisal system more difficult.
Producing and using case material for research and teaching: a workshop for partners in know‐how transfer projects
Authors: Nelson Edwin
Published: July 2002

Demonstrates the structure and approach used in a workshop to train trainers in case research and writing skills. The purpose of the workshop is to apply basic principles to the design of a practical methodology for monitoring and evaluating the outcomes of training programmes and to produce indigenous training materials for future courses in the field of business development and entrepreneurship. The research subjects are new entrepreneurs and new enterprise ventures in a transitional economy. The context is a know‐how transfer project designed to develop the capability of the staff of an eastern European partner institution. The workshop approach is presumed to be an effective mechanism for concept sharing to avoid the worst of the obstacles that can be encountered due to differences in culture and language. Deals with questions of principle and application in two parallel themes, presenting general principles for case research and case writing, and describing how the case research team applied them to produce a practical methodology to achieve their own project objectives. Concludes that the model works effectively to achieve the training objectives.
Financial decision making: teacher involvement and the need for trust
Authors: Newcombe Geoffrey , McCormick John , Sharpe Fenton
Published: July 2002

Suggests that a desire on the part of teachers to be more involved in the corporate affairs of the school may stem from a lack of trust in the decision makers and the decision‐making processes. To assist those involved in the management of schools, presents a theoretical framework for research and a financial decision‐making model, based on the establishment of a management philosophy built on trust. Demonstrates how this model helps to differentiate management and classroom or technical decisional issues. Identifies the roles and responsibilities of those involved in the processes. Outlines procedures for effective financial decision making at the school site.
Decision‐making assessment: improving principal performance
Authors: Calabrese Raymond L. , Zepeda Sally J.
Published: July 2002

The process of training and preparing principals is driven by a characteristics model. Underlying each of the components in the characteristics model is decision making. Decision making defines the work of principals. Those who prepare principals can improve the leadership quality of principals and thereby impact school effectiveness by focusing on decision making. Decision‐making assessment is a critical component to principal preparation and ongoing development. It can be used to assess the quality of decisions made by prospective and acting school administrations. Through decision‐making assessment principals can become aware of their cognitive decision‐making patterns thus allowing them opportunity to replace potentially dysfunctional patterns with patterns that are more effective and efficient.
KPMG survey: the IT outsourcing decision
Authors: Hurley Margaret , Schaumann Folker
Published: July 2002

Presents the results of KPMG’s survey on the current IT outsourcing practices in Australia, to which 300 organizations responded. Demonstrates a high rate of usage of outsourced IT services in the country. Describes the major reasons for embarking on an outsourcing project and the extent to which objectives are currently being met. Emphasizes the importance of determining the parameters of an outsourcing arrangement in as much detail as possible in advance of the transition.
Security implications of electronic commerce: a survey of consumers and businesses
Authors: Furnell S.M. , Karweni T.
Published: July 2002

Examines the general requirement for security technologies in order to provide a basis for trust in the e‐commerce environment. The discussion is supported by the findings from two surveys, conducted by the authors, among general Internet users (i.e. potential target consumers) and commercial businesses. These surveys considered both the attitudes to e‐commerce in general and opinions relating to the associated security requirements. Attempts were also made to assess the respondent’s knowledge of the existing security safeguards that may be applied. The survey results suggest that, while there is significant concern among Internet‐based consumers regarding the security of their purchasing activities, these are outweighed by the merits offered by the medium. The results also suggested a lack of awareness or understanding of the security technologies that are available and it is concluded that overcoming this problem would help to establish a wider foundation of trust in the new technology.
Proton and metal ion‐dependent assembly of a model diiron protein
Authors: Pasternak Annette , Kaplan Justin , Lear James D. , Degrado William F.
Published: July 2002

DF1 is a small, idealized model for carboxylate‐bridged diiron proteins. This protein was designed to form a dimeric four‐helix bundle with a dimetal ion‐binding site near the center of the structure, and its crystal structure has confirmed that it adopts the intended conformation. However, the protein showed limited solubility in aqueous buffer, and access to its active site was blocked by two hydrophobic side chains. The sequence of DF1 has now been modified to provide a very soluble protein (DF2) that binds metal ions in a rapid and reversible manner. Furthermore, the DF2 protein shows significant ferroxidase activity, suggesting that its dimetal center is accessible to oxygen. The affinity of DF2 for various first‐row divalent cations deviates from the Irving–Willliams series, suggesting that its structure imparts significant geometric preferences on the metal ion‐binding site. Furthermore, in the absence of metal ions, the protein folds into a dimer with concomitant binding of two protons. The uptake of two protons is expected if the structure of the apo‐protein is similar to that of the crystal structure of dizinc DF1. Thus, this result suggests that the active site of DF2 is retained in the absence of metal ions.
Group Classification and Generalized Conditional Symmetry Reduction of the Nonlinear Diffusion–Convection Equation with a Nonlinear Source
Authors: Qu Changzheng
Published: July 2002

The generalized conditional symmetry method, which can be considered a generalization of the conditional symmetry method, is used to study the nonlinear diffusion–convection equations with a nonlinear source. In particular, exponential and power law diffusivities are examined and we obtain mathematical forms of the convective term and the source term, which permit the generalized conditional symmetry reductions. A number of examples are considered and some exact solutions are constructed via the compatibility of the generalized conditional symmetry and the considered equation.
Mean‐Variance Hedging and Numéraire
Authors: Gourieroux Christian , Laurent Jean Paul , Pham Huyên
Published: July 2002

We consider the mean‐variance hedging problem when the risky assets price process is a continuous semimartingale. The usual approach deals with self‐financed portfolios with respect to the primitive assets family. By adding a numéraire as an asset to trade in, we show how self‐financed portfolios may be expressed with respect to this extended assets family, without changing the set of attainable contingent claims.

We introduce the hedging numéraire and relate it to the variance‐optimal martingale measure. Using this numéraire both as a deflator and to extend the primitive assets family, we are able to transform the original mean‐variance hedging problem into an equivalent and simpler one; this transformed quadratic optimization problem is solved by the Galtchouk–Kunita–Watanabe projection theorem under a martingale measure for the hedging numéraire extended assets family. This gives in turn an explicit description of the optimal hedging strategy for the original mean‐variance hedging problem.
Hypoxia inhibits human recombinant large conductance, Ca2+‐activated K+ (maxi‐K) channels by a mechanism which is membrane delimited and Ca2+ sensitive
Authors: Lewis A. , Peers C. , Ashford M. L. J. , Kemp P. J.
Published: July 2002

Large conductance, Ca2+‐activated K+ (maxi‐K) channel activity was recorded in excised, inside‐out patches from HEK 293 cells stably co‐expressing the α‐ and β‐subunits of human brain maxi‐K channels. At +50 mV, and in the presence of 300 nm Ca2+i, single channel activity was acutely and reversibly suppressed upon reducing PO2 from 150 to > 40 mmHg by over 30 %. The hypoxia‐evoked reduction in current was due predominantly to suppression in NPo, although a minor component was attributable to reduced unitary conductance of 8–12 %. Hypoxia caused an approximate doubling of the time constant for activation but was without effect on deactivation. At lower levels of Ca2+i(30 and 100 nm), hypoxic inhibition did not reach significance. In contrast, 300 nm and 1 μm Ca2+i both sustained significant hypoxic suppression of activity over the entire activating voltage range. At these two Ca2+i levels, hypoxia evoked a positive shift in the activating voltage (by ∼10 mV at 300 nm and ∼25 mV at 1 μm). At saturating [Ca2+]i (100 μm), hypoxic inhibition was absent. Distinguishing between hypoxia‐evoked changes in voltage‐ and/or Ca2+i‐sensitivity was achieved by evoking maximal channel activity using high depolarising potentials (up to +200 mV) in the presence of 300 nm or 100 μm Ca2+i or in its virtual absence (> 1 nm). Under these experimental conditions, hypoxia caused significant channel inhibition only in the presence of 300 nm Ca2+i. Thus, since regulation was observed in excised patches, maxi‐K channel inhibition by hypoxia does not require soluble intracellular components and, mechanistically, is voltage independent and Ca2+i sensitive.
Finite Element Modeling of Burr Formation Process in Drilling 304 Stainless Steel
Authors: Guo Y. B. , Dornfeld D. A.
Published: July 2002

A 3D finite element model was developed for the simulation of drilling burr formation processes of 304L stainless steel. The nonlinear thermo-elastic-plastic model simultaneously accounts for dynamic effects of mass and inertia, strain hardening, strain rate, automatic mesh contact with friction capability, material ductile failure and temperature-mechanical coupling. Material ductile failure criteria were proposed to simulate drilling burr formation. Based on a series of stress contours and the progressive deformation of the workpiece edge obtained from simulation, a drilling burr formation mechanism was proposed and divided into four stages: initiation, development, pivoting point, and formation stages with cap formation. The burr thickness is largely determined by the distance between the pre-defined machined surface and the pivoting point, while the burr height is determined by the positions of the pivoting point and the cap formation. The FEM simulation demonstrates the dominant roles of negative shearing and bending mechanisms in the drilling burr formation process. The simulation results coincide with phenomenological observations of burr geometry from drilling 304 stainless steel and plasticine work materials. [S1087-1357(00)01202-8]
Nucleation and Bubble Dynamics In Vortical Flows
Authors: Arndt Roger E. A. , Maines Brant H.
Published: July 2002

The cavitation inception process in trailing vortices has been studied for several years. One of the important findings from these studies is the strong sensitivity to nuclei size and number as well as significant viscous effects. In order to understand the nucleation and bubble growth process in more detail, a photographic study was conducted with the aim of developing high quality visualizations of the dynamical growth of bubbles. [S0098-2202(00)00403-X]
Optimal Design Using Chaotic Descent Method
Authors: Jovanovic Vojin , Kazerounian Kazem
Published: July 2002

This paper describes a method for searching of global minima in design optimization problems. The method is applicable to any general nonlinear function. It is based on utilizing sensitive fractal areas to locate all of the solutions along one direction in a variable space. The search begins from an arbitrary chosen point in the variable space and descends towards a better design along a randomly chosen direction. Descent depends on finding points that belong to a fractal set which can be used to locate all of the solutions along that direction. The process is repeated until optimal design is obtained. To examine the behavior of the algorithm appropriate examples were selected and results discussed. [S1050-0472(00)00703-0]
An Experimental Study of Molten Microdroplet Surface Deposition and Solidification: Transient Behavior and Wetting Angle Dynamics
Authors: Attinger D. , Zhao Z. , Poulikakos D.
Published: July 2002

The basic problem of the impact and solidification of molten droplets on a substrate is of central importance to a host of processes. An important and novel such process in the area of micromanufacturing is solder jetting where microscopic solder droplets are dispensed for the attachment of microelectronic components. Despite the recent appearance of a few numerical studies focusing on the complex transient aspects of this process, no analogous experimental results have been reported to date to the best of our knowledge. Such a study is reported in this paper. Eutectic solder (63Sn37Pb) was melted to a preset superheat and used in a specially designed droplet generator to produce droplets with diameters in the range 50–100 μm. In a first series of experiments, the size, temperature, and impacting speed of the molten droplets were maintained constant. The primary variable was the temperature of the substrate that was controlled in the range from 48°C to 135°C. The dynamics of molten solder microdroplet impact and solidification on the substrate was investigated using a flash microscopy technique. The time for the completion of solidification from the moment of a solder droplet impact on the substrate varies between 150 μs and 350 μs. The dynamic interaction between the oscillation in the liquid region and the rapid advance of the solidification front was visualized, quantified, and presented in this paper. In a second series of experiments, the evolution of the wetting angle between the spreading drop and the substrate was recorded and analyzed. No quantitative agreement with Hoffman’s correlation for wetting was found. It was established that the wetting angle dynamics is strongly coupled with the evolution of the droplet free surface. Two successive regimes were distinguished during the spreading. The influence of the initial impact velocity and substrate temperature on the dynamics of the measured wetting angle was described in both regimes. To the best of our knowledge, this study presents the first published experimental results on the transient fluid dynamics and solidification of molten microdroplets impacting on a substrate at the above-mentioned time and length scales that are directly relevant to the novel solder jetting technology. [S0022-1481(00)01403-1]
Stability Analysis and Finite Element Simulation of Bone Remodeling Model
Authors: Zidi M. , Ramtani S.
Published: July 2002

Bone remodeling is widely viewed as a dynamic process—maintaining bone structure through a balance between the opposed activities of osteoblast and osteoclast cells—in which the stability problem is often pointed out. By an analytical approach, we present a bone remodeling model applied to n unit-elements in order to analyze the stationary states and the condition of their stability. In addition, this theory has been simulated in a computer model using the Finite Element Method (FEM) to show a relationship between the bone remodeling process and the stability analysis. [S0148-0731(00)01806-9]
A Computational Study of Bubble-Structure Interaction
Authors: Chan Philemon C. , Kan Kit K. , Stuhmiller James H.
Published: July 2002

The complex interaction between underwater explosion bubbles and nearby structures is studied using two-fluid computational fluid dynamics. Gravitational effects on bubble jetting are significantly different between jet-up and jet-down orientations. This paper presents computational results of underwater explosion bubble dynamics near a disk and a sphere. The results show that the bubble jetting and collapse phenomena and the consequent pressure loading are affected by the structure’s shape, the orientation of the bubble to the structure, and the bubble depth. A unifying notion emerges connecting jet strength at impact to bubble curvature at the time of jet formation. [S0098-2202(00)01804-6]
Improving Startup Behavior of Fluid Couplings Through Modification of Runner Geometry: Part I—Fluid Flow Analysis and Proposed Improvement
Authors: Huitenga H. , Mitra N. K.
Published: July 2002

For the use as a startup device the characteristic of a hydrodynamic coupling has to be steep at the nominal high speed operation condition and flat in the range of lower speed ratios. The economical design of the runner requires that the mass and the volume of the coupling should be as small as possible. The flow field in a starting configuration is simulated and a detailed analysis of the three-dimensional flow field is performed to deduce constructional modifications which meet both requests. The analysis shows that several modifications on pump and turbine runner seem to be successful. The consequences of the variation of the runner geometries will be discussed in detail in Part II of this paper. [S0098-2202(00)02104-0]
Thermodynamic Performance of Ice Thermal Energy Storage Systems
Authors: Rosen Marc A. , Dincer Ibrahim , Pedinelli Norman
Published: July 2002

The thermodynamic performance of an encapsulated ice thermal energy storage (ITES) system for cooling capacity is assessed using exergy and energy analyses. A full cycle, with charging, storing, and discharging stages, is considered. The results demonstrate how exergy analysis provides a more realistic and meaningful assessment than the more conventional energy analysis of the efficiency and performance of an ITES system. The overall energy and exergy efficiencies are 99.5 and 50.9 percent, respectively. The average exergy efficiencies for the charging, discharging, and storing periods are 86, 60, and over 99 percent, respectively, while the average energy efficiency for each of these periods exceeds 99 percent. These results indicate that energy analysis leads to misleadingly optimistic statements of ITES efficiency. The results should prove useful to engineers and designers seeking to improve and optimize ITES systems. [S0195-0738(00)00904-3]
Estimation of Bone Matrix Apparent Stiffness Variation Caused by Osteocyte Lacunar Size and Density
Authors: Yeni Yener N. , Vashishth Deepak , Fyhrie David P.
Published: July 2002

The role of osteocyte lacunar size and density on the apparent stiffness of bone matrix was predicted using a mechanical model from the literature. Lacunar size and lacunar density for different bones from different gender and age groups were used to predict the range of matrix apparent stiffness values for human cortical and cancellous tissue. The results suggest that bone matrix apparent stiffness depends on tissue type (cortical versus cancellous), age, and gender, the magnitudes of the effects being significant but small in all cases. Males had a higher predicted matrix apparent stiffness than females for vertebral cancellous bone p<10−7)and the difference increased with age p=0.0007. In contrast, matrix apparent stiffness was not different between males and females for femoral cortical bone and increased with age in both males p<0.0001 and females p<0.0364. Osteocyte lacunar density and size may cause significant gender and age-related variations in bone matrix apparent stiffness. The magnitude of variations in matrix apparent stiffness was small within the physiological range of lacunar size and density for healthy bone, whereas the variations can be profound in certain pathological cases. It was proposed that the mechanical effects of osteocyte density be uncoupled from their biological effects by controlling lacunar size in normal bone.