bluuebunny/crossref_metadata_2025 huggingface dataset:
Comparative regression analysis coupled with rational verification for forecasting night cooling
Authors: Michaelides Silas Chr.
Published: May 2007

A set of linear regression equations has been developed for forecasting night‐time minimum temperatures. The predictors used in each regression are the dry‐bulb and wet‐bulb temperatures recorded at various times during the day. This set of regression equations can be used to begin estimating the expected minimum temperature early in the day and then update the estimate in the course of the day. It is shown that these regression equations are quite insensitive to small deviations in the input data and some special cases are discussed. The usefulness of simple or multiple regression is also examined. Under certain conditions, linear regression on hygrometrically derived humidity parameters have been transformed into non‐linear expressions of dry and wet‐bulb temperatures. It is shown by an example that these non‐linear relationships may fit the data equally as well as the linear relationships. Comparative verification of the scheme has shown that successive updating of the predicted minimum temperature has certain advantages. Questions associated with the representativeness of the data base are also discussed. The effect of the turbulent mixing by the wind on the night cooling is incorporated in the scheme as a further upgrading of the method.
Estimating a reduced rank regression model for non‐normal variables
Authors: Bijleveld Catrien C. J. H. , Van Montfort Kees
Published: May 2007

A method using third order moments for estimating the regression coefficients as well as the latent state scores of the reduced‐rank regression model when the latent variable(s) are non‐normally distributed is presented in this paper. It is shown that the factor analysis type indeterminacy of the regression coefficient matrices is eliminated. A real life example of the proposed method is presented. Differences of this solution with the reduced‐rank regression eigen solution are discussed.
A note about the Gaussian property of the Brownian bridge
Authors: Gutiérrez Ramón , Valderrama Mariano J.
Published: May 2007

The Gaussian property of the Brownian bridge is characterized as an application of Ramachandran's theorem in terms of the independence of the random variables that appear in the Karhunen‐Loéve expansion of the process. A reference about the construction of the Brownian bridge by means of functional transformations is also included.
Linear‐quadratic efficient frontiers for portfolio optimization
Authors: King Alan J. , Jensen David L.
Published: May 2007

Finding portfolios with given mean return and minimal lower partial mean or variance, two risk criteria of interest in the theory of optimal portfolio selection, is a stochastic linear‐quadratic program that can be converted to a large‐scale linear or quadratic program when the asset returns are finitely distributed. These efficient frontiers can be computed on presently available platforms for problems of reasonable size; we discuss our experience with a problem involving one thousand assets. Asymptotic statistics for stochastic programs can be applied to justify sampling as a means to approximate continuous distributions by finite distributions.
Product forms for availability models
Authors: Smeitink Eric , van Dijk Nico M. , Haverkort Boudewijn R.
Published: May 2007

This paper shows and illustrates that product form expressions for the steady state distribution, as known for queueing networks, can also be extended to a class of availability models. This class allows breakdown and repair rates from one component to depend on the status of other components. Common resource capacities and repair priorities, for example, are included. Conditions for the models to have a product form are stated explicitly. This product form is shown to be insensitive to the distributions of the underlying random variables, i.e. to depend only on their means. Further it is briefly indicated how queueing for repair can be incorporated. Novel product form examples are presented of a simple series/parallel configuration, a fault tolerant database system and a multi‐stage interconnection network.
A modified candecomp algorithm for fitting the latent class model: Implementation and evaluation
Authors: Carroll J. Douglas , De Soete Geert , Kamensky Victor
Published: May 2007

In this paper an implementation is discussed of a modified CANDECOMP algorithm for fitting Lazarsfeld's latent class model. The CANDECOMP algorithm is modified such that the resulting parameter estimates are non‐negative and ‘best asymptotically normal’. In order to achieve this, the modified CANDECOMP algorithm minimizes a weighted least squares function instead of an unweighted least squares function as the traditional CANDECOMP algorithm does. To evaluate the new procedure, the modified CANDECOMP procedure with different weighting schemes is compared on five published data sets with the widely‐used iterative proportional fitting procedure for obtaining maximum likelihood estimates of the parameters in the latent class model. It is found that, with appropriate weights, the modified CANDECOMP algorithm yields solutions that are nearly identical with those obtained by means of the maximum likelihood procedure. While the modified CANDECOMP algorithm tends to be computationally more intensive than the maximum likelihood method, it is very flexible in that it easily allows one to try out different weighting schemes.
Fractional brownian motion modelling of pressure fluctuations in multiphase flow systems
Authors: Neogi D. , Nassar R. , Fan L. T.
Published: May 2007

Multiphase flow systems lend themselves to a stochastic description due to their random behaviour. Fluidized beds and bubble columns are notable examples of such systems wherein random generation and coalescence of bubbles lead to pressure and density fluctuations. Analyses of these systems utilizing short‐memory models based on Markovian assumptions have been widely reported. Nevertheless, a review of the available data and the results of preliminary experiments have indicated that the time series of pressure fluctuation signals from various multiphase flow systems exhibit a a long‐term correlation. These signals appear to be better described by a long‐memory model, specifically “fractional Brownian motion” (FBM) comprising fractional Gaussian noise (FGN). In the present work, pressure fluctuations in a gas‐solid fluidized bed and a bubble column have been analysed and modelled by resorting to the relatively new concept of FBM. The stochastic model developed visualizes the bubble motion in a multiphase flow system to be composed of a random movement, generating irregular signals, and a linear movement, generating wave‐like signals. Autocorrelation and spectral density functions have been derived from the model. Comparison between the model‐based and experimentally determined autocorrelation functions has indicated that FBM is indeed a viable model for pressure fluctuations in multiphase flow systems.
Analysis of a closed‐loop manufacturing system with finite buffers
Authors: Bouhchouch Abdellatif , Frein Yannick , Dallery Yves
Published: May 2007

In this paper, we are interested in the analysis of a closed loop manufacturing system with finite buffers. More precisely, the system we consider is a production line consisting of a series of machines separated by buffers of finite capacity. In addition, parts need to be mounted onto pallets during their processing through the production line. Our aim is to develop an analytical method for performance evaluation of this class of manufacturing systems. The main performance parameter of interest when designing such a system is the production capacity, i.e. the maximal production rate that can be obtained. It is a function of the processing times at the different machines, the buffer sizes, as well as the total number of pallets that are available. For this purpose, we model the system as a closed queuing network with finite capacity queues. We propose a new approximation method to calculate the performance of such queuing networks. The principle is to decompose the closed queuing network into a set of subsystems, each subsystem modelling the flow of material in one of the buffers of the network. The population constraint of the closed network is taken into account by ensuring that the sum of the average queue lengths of the different subsystems is equal to the number of the customers of the network. We present numerical results that show that the method has a fairly good qualitative as well as quantitative behaviour.
A language for numerical construction of applied stochastic models via redundant data
Authors: Samaratunga P. Chand
Published: May 2007

A language is described for rapid implementation of algebraic operations on random variables that can be used for numerical construction of stochastic models. A “data object” describing the probability distribution function of a random variable may consist of mutually redundant data‐sets such as: a sampling of its probability distribution function, coefficients of the moment generator function, fast Fourier transform of a sampling of the probability density function, a set of bilateral PHase (BPH) coefficients, fast Fourier transform of a set of BPH coefficients, a set of Laguerre transform coefficients, and other representations. We exploit this redundancy of data representations in implementing our language and in obtaining a computational speed‐up for random variable manipulations. If X and Y are two random variables, the operation of addition to evaluate X + Y is implemented in a simple high‐level language construct “+”. The language is also provided with the capability of easily supporting other user‐defined algebraic operations for random variables. This language (RANL) is a powerful computational tool that can be used to build complex and realistic numerical stochastic models rapidly. The operators used in RANL for manipulation of random variables are extensions of arithmetic operators for real numbers.
Assessing the predictive effectiveness of the variety seeking and reinforcement models
Authors: Sarigöllü Emine
Published: May 2007

Prediction of customer choice behaviour has been a big challenge for marketing researchers. They have adopted various models to represent customers purchase patterns. Some researchers considered simple zero–order models. Others proposed higher–order models to represent explicitly customers tendency to seek [variety] or [reinforcement] as they make repetitive choices. Nevertheless, the question [Which model has the highest probability of representing some future data?] still prevails. The objective of this paper is to address this question. We assess the predictive effectiveness of the well–known customer choice models. In particular, we compare the predictive ability of the [dynamic attribute satiation] (DAS) model due to McAlister (Journal of Consumer Research, 91, pp. 141–150, 1982) with that of the well–known stochastic variety seeking and reinforcement behaviour models. We found that the stochastic [beta binomial] model has the best predictive effectiveness on both simulated and real purchase data. Using simulations, we also assessed the effectiveness of the stochastic models in representing various complex choice processes generated by the DAS. The beta binomial model mimicked the DAS processes the best. In this research we also propose, for the first time, a stochastic choice rule for the DAS model.
Time series analysis for ground penetrating radar (GPR) asphalt thickness profile
Authors: Nii. Attoh‐Okine B.
Published: May 2007

Time series obtained from the waveform profiles of the ground penetrating radar (GPR) thickness of the asphaltic concrete layers of in–service pavement holds a key to the understanding of thickness variation and the presence of cavities within and below the pavement surface. In this paper, the fundamental techniques of time series modelling—(i) identification, (ii) estimation and (iii) diagnostics—are applied to the GPR thickness profile of three types of pavement—(a) fully–designed (b) partially–designed and (c) compositely designed pavement. Actual applications are made using data from in–service pavement in the state of Kansas. The main purpose of this study is to investigate the mechanism that drives the data and to compare the model errors and statistics of the thickness profiles of different types of flexible pavement. In the present study, the time series is replaced by a distance scale, but the name time series is retained.
Evaluating departures from fair representation
Authors: Bondarczuk Z. , Kowalczyk T. , Pleszczyńska E. , Szczesny W.
Published: May 2007

Computer–intensive estimates are introduced to evaluate departures from proportionality between the numbers of electors in a partition of a voting population and the numbers of representatives in the corresponding partition of the elected representation. At the first stage a pair of indices is proposed, one to evaluate the total strength of the departures and the other to indicate to what extent they are due to over–representation increasing (or decreasing) with the number of electors in a group. The properties of the indices are examined in suitably defined stochastic models which describe this type of over–representation. Since the values of the indices are strongly influenced by the distribution of electors in the given partition, a second stage of estimation is performed in order to get some [partition–free] information on the existence of a monotone size representation, and, if it exists, on its strength. The relevant transformation is based on intensive computer simulation in the introduced models. The methods proposed are applied to the results of the 1991 election of the Polish Scientific Research Council, which distributes funds among universities, scientific institutions and individual groups of researchers.
Examples of fitting structured phase–type distributions
Authors: Faddy M. J.
Published: May 2007

A sub–class of phase–type distributions is defined in terms of a Markov process with sequential transitions between transient states and transitions from these states to absorption. Such distributions form a very rich class; they can be fitted to data, and any structure revealed by the parameter estimates used to develop more parsimonious re–parametrizations. Several example data sets are used as illustrations.
Periodicity of equilibrium structures in a time dependent markov model under stochastic environment
Authors: Tsantas N. , Georgiou A. C.
Published: May 2007

The problem of periodicity for a non–homogeneous Markov model in a stochastic environment is studied. The stochastic concept is established through the notion of optional scenarios applied on the transition process. It is proved that the sequence of so–called aggregate structures follows a certain periodic pattern that can split into converging subsequences according to alternative policies. These limits are highly influenced by the different scenarios utilized in the model, but always lie on a convex region that also depends on the pool of alternatives.
Dynamic modelling of life table data
Authors: Janssen J. , Skiadas C. H.
Published: May 2007

In this paper we formulate a dynamic model expressing the human life table data by using the first‐passage‐time theory for a stochastic process. The model is derived analytically and then is applied to the mortality data in Belgium and France. A stochastic simulation is also performed for the ‘health state function’ proposed and the related stochastic paths. Furthermore the implications of the proposed model and the results derived for pension funds and option theory are discussed.
A periodic cointegration model of quarterly consumption
Authors: Franses Philip Hans , Kloek Teun
Published: May 2007

A periódic cointegration model is proposed to describe quarterly observed consumption. This model allows the cointegrating vectors and the adjustment parameters to vary with the seasons. Its links are discussed with an often considered standard economic theoretical model for macroeconomic variables like consumption. A simple empirical model specification strategy is given and applied to Austrian consumption and income data.
Textilbewehrter Beton: Tragverhalten, Bemessung und Anwendung
Authors: Hegger Josef , Horstmann Michael , Voss Stefan , Will Norbert
Published: June 2007

Gegenwärtig ist ein zunehmendes Interesse von Architekten und Planern am Einsatz von textilbewehrtem Beton als Konstruktionswerkstoff zu beobachten. Die Anwendung bei filigranen, selbsttragenden Vorhangfassaden stellt derzeit den Stand der Technik dar. In aktuellen Untersuchungen werden auch Potenziale für leichte Tragstrukturen bewertet. Die für eine zielsichere Bemessung der Bauteile erforderlichen Modelle sind Gegenstand der Forschungsarbeiten im Sonderforschungsbereich 532 an der RWTH Aachen. Eine Zusammenfassung wesentlicher Forschungsergebnisse und deren Umsetzung in ersten Anwendungsprojekten wird nachfolgend vorgestellt.
Intra-anal application of l-erythro methoxamine gel increases anal resting pressure in patients with incontinence
Authors: Nisar P J , Gruss H-J , Bush D , Acheson A G , Scholefield J H
Published: June 2007

Background

This study examined the effects of a single dose of intra-anal l-erythro methoxamine on mean anal resting pressure (MARP) and cardiovascular variables in patients with faecal incontinence.

Methods

Patients had anorectal physiology tests and ultrasonography before participating. Six patients received 0·3 and 1 per cent gels on separate days, two patients received 0·3 per cent gel, and two patients received 1 per cent gel. MARP, blood pressure, pulse rate and plasma drug concentrations were measured for 6 h after application.

Results

Intra-anal 0·3 per cent gel caused a rapid, significant rise in MARP lasting 2 h (P = 0·036). In four of these patients, the response was sufficient to increase MARP to within the normal range at 2 h. Application of 1 per cent gel caused a significant rise in MARP for 4 h after application (P = 0·028). There was a significant decrease in pulse at 2 and 1 h respectively after application of 0·3 and 1 per cent gels.

Conclusion

Intra-anal application of l-erythro methoxamine can be used to increase MARP in patients with faecal incontinence. Application of 1 per cent l-erythro methoxamine gel produced a rapid, sustained rise in MARP, which raises the possibility of therapeutic application.
Die Synthese von Mandelsäure‐Analogen, II. Mitteil.: Über Styrylglykolsäuren
Authors: Nerdel Friedrich , Rachel Hans
Published: June 2007

Es wird über die Darstellung und optische Spaltung von Styrylglykolsäure und [3‐Nitro‐styryl]‐glykolsäure berichtet. Die Rotationsdispersionen der Säuren und ihrer Derivate werden mitgeteilt. Der konfigurative Zusammenhang dieser Säuren mit der α‐Hydroxy‐γ‐phenyl‐buttersäure wird ermittelt und deren absolute Konfiguration wahrscheinlich gemacht.
Über das dritte racemische Cocain
Authors: Zeile Karl , Schulz Werner
Published: June 2007

Durch Methylierung und Benzoylierung des 3. (±) Ekgonins wurde das dritte (±) Cocain gewonnen, das sich im pharmakologischen Test auf Lokalanästhesie als unwirksam erwies.
Zur Kenntnis der Amadori‐Umlagerung
Authors: Micheel Fritz , Schleppinghoff Bernhard
Published: June 2007

Die Fähigkeit aromatischer N‐Glykoside, die Amadori‐Umlagerung einzugehen, wird durch o/p‐dirigierende Substituenten in der 2‐ oder 4‐Stellung zum N‐Atom begünstigt, durch m‐dirigierende in 2‐oder 4‐Stellung erschwert. Umgekehrt wirken o/p‐dirigierende in 3‐Stellung erschwerend, m‐dirigierende in 3‐Stellung jedoch fördernd. Chlor‐Substitution in 3‐ oder 4‐Stellung wirkt erschwerend. Die Amadori‐Produkte zeigen im IR‐Spektrum eine charakteristische Bande bei 3570 cm−1.
Über Einige Urankomplexe der Formazyl‐ und der Azomethin‐Reihe
Authors: Seyhan Muvaffak , Fernelius W. Conard
Published: June 2007

Es wird die Darstellung dreier Urankomplexe der Formazyl‐ und der Azomethin‐Reihe beschrieben. Die Konstitution der beiden Urankomplexe der Formazyl‐Reihe wird ermittelt.
Stereoselective Carbonyl Allylation by Umpolung of Allylpalladium(II) Complexes
Authors: Zanoni Giuseppe , Pontiroli Alessandro , Marchetti Alberto , Vidari Giovanni
Published: May 2007

The nucleophilic palladium‐mediated allylation of a carbonyl group requires the inversion of the reactivity (umpolung) of the η3‐allylpalladium moiety. If the reaction is performed with a metal more electropositive than palladium, the stereochemical outcome is influenced by the solvent and by the reagent used for the umpolung. The stereoselectivity is also determined by the rate of η3–η1–η3 equilibration of the η3‐allylpalladium system relative to that of the transmetallation and addition to the aldehyde. When the umpolung is carried out with η1‐ or bis(allylpalladium) complexes, the stereoselectivity mainly depends on the nature of the substituents on the allyl fragment. Asymmetric addition has been achieved by using chiral ligands that promote palladium‐mediated reactions with “hard” nucleophiles. Utilization of selected chiral monophosphanes/phosphoramidite as ligands induces enantioselectivity that depends on the nature of the aldehyde as well as of the umpolung agent. Modest enantiomeric excesses have been obtained by using preformed bis(allylpalladium) systems with one chiral allylic fragment.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Mimicking the Binding Motifs Found in the Crystal Structures of Protein–Carbohydrate Complexes: An Aromatic Analogue of Serine or Threonine Side Chain Hydroxyl/Main Chain Amide
Authors: Mazik Monika , König Alexander
Published: May 2007

An aromatic analogue of the side chain hydroxyl/main chain amide of Ser or Thr was used for the construction of artificial receptors forN‐acetylneuraminic acid (Neu5Ac), the most common occurring sialic acid. The acyclic receptors, incorporating only neutral recognition sites, are able to bind Neu5Ac with an overall binding constantβ2of 105M–2in a competitive solvent, such as water‐containing [D6]DMSO. Both receptors show remarkable selectivity for Neu5Ac overD‐glucuronic acid (GlcA).(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2007)
Cell cycle alteration and decreased cell proliferation in the hippocampal dentate gyrus and in the neocortical germinal matrix of fetuses with down syndrome and in Ts65Dn mice
Authors: Contestabile Andrea , Fila Tatiana , Ceccarelli Claudio , Bonasoni Paola , Bonapace Laura , Santini Donatella , Bartesaghi Renata , Ciani Elisabetta
Published: June 2007

Down syndrome (DS), the leading genetic cause of mental retardation, is characterized by reduced number of cortical neurons and brain size. The occurrence of these defects starting from early life stages points at altered developmental neurogenesis as their major determinant. The goal of our study was to obtain comparative evidence for impaired neurogenesis in the hippocampal dentate gyrus (DG) of DS fetuses and Ts65Dn mice, an animal model for DS. Cell proliferation in human fetuses was evaluated with Ki‐67 (a marker of cells in S + G2 + M phases of cell cycle) and cyclin A (a marker of cells in S phase) immunohistochemistry. We found that in the DG of DS fetuses the number of proliferating cells was notably reduced when compared with controls. A similar reduction was observed in the germinal matrix of the lateral ventricle. In both structures, DS fetuses showed a reduced ratio between cyclin A‐ and Ki‐67‐positive cells when compared with controls, indicating that they had a reduced number of cycling cells in S phase. In the DG of P2 Ts65Dn mice cell proliferation, assessed 2 h after an injection of bromodeoxyuridine (BrdU), was notably reduced, similarly to DS fetuses. After 28 days, Ts65Dn mice had still less BrdU‐positive cells than controls. Phenotypic analysis of the surviving cells showed that Ts65Dn mice had a percent number of cells with astrocytic phenotype larger than controls. Using phospho‐histone H3 immunohistochemistry we found that both DS fetuses and P2 Ts65Dn mice had a higher number of proliferating cells in G2 and a smaller number of cells in M phase of cell cycle. Results provide novel evidence for proliferation impairment in the hippocampal DG of the DS fetal brain, comparable to that of the P2 mouse model, and suggest that cell cycle alterations may be critical determinants of the reduced proliferation potency. © 2007 Wiley‐Liss, Inc.
A scheme to involve managers in training
Authors: Gitzendanner Charles
Published: June 2007

This is a plan to allow managers to develop a priority of training needs and the cost/result relationships of the programs planned to meet such needs.
Arbitrators and the seniority rights of foremen
Authors: Harris Philip
Published: June 2007

When arbitrators must decide the seniority rights of displaced foremen, how much do management's rights suffer?
Consequences of extended work hours: A comparison of moonlighters, overtimers, and modal employees
Authors: Jamal Muhammad , Crawford Ronald L.
Published: June 2007

Stringent corporate controls on employee moonlighting and/or overtime are not uncommon. But are they necessary? Even the concept of overtime may need to be rethought—what about the “normal working hours” of managers and professionals who work hours at home or on the road—hours typically uncompensated?
Gainsharing: A few questions, and fewer answers
Authors: Bullock R. J. , Lawler Edward E.
Published: June 2007

Gainsharing is an important organization development intervention, yet many of the basic questions have not been answered. This paper addresses these questions by developing a conceptual model and using the model to review the case study literature on gainsharing. The plans varied in terms of structural factors, implementation factors, and situational factors, and a majority were successful. Gainsharing impact was found in five key areas: organizational effectiveness, individual quality of work life, ideas and innovation, labormanagement cooperation, and pay. Relevant research is briefly reviewed and several unanswered questions are identified for future research.
Human resource management strategies in declining industries
Authors: Ferris Gerald R. , Schellenberg Deborah A. , Zammuto Raymond F.
Published: June 2007

The conceptualization presented in this article suggests that top management should take into account the role of the human resource function in formulating and implementing strategic responses to decline. Such responses must be formulated within the context of the skills and knowledge available to the organization and according to the type of environmental conditions encountered. These influences will force the human resource manager to focus on sharpening competencies existing within the organization, consolidating competencies so that only those currently required by the organization are retained, adding new competencies, or replacing existing competencies so that the organization can move to a new domain activity. The emphasis on human resource processes such as recruitment and termination, training and development, and evaluation, reward, and retention for purposes of development and maintenance of the competencies needed to implement strategic responses to decline will vary according to the nature of the environmental conditions encountered.
Subordinate appraisal: A valuable source of information about managers
Authors: Bernardin H. John
Published: June 2007

The use of subordinates for managerial performance appraisal is discussed and the advantages and disadvantages are presented. While the empirical data is limited, that which does exist supports the use of subordinates for both feedback purposes and personnel decisions. A set of prescriptions is provided for implementation.
Human resource management practice in China: A future perspective
Authors: Cyr Dianne J. , Frost Peter J.
Published: June 2007

In response to cultural and economic changes, human resource practitioners can potentially play a role of balancing tensions in the organization. A future perspective of new roles and structures for HRM is considered in the Chinese context. Possible directions for research are outlined.
An examination of the relationships among self‐perception accuracy, self‐awareness, gender, and leader effectiveness
Authors: Van Velsor Ellen , Taylor Sylvester , Leslie Jean B.
Published: June 2007

This article focuses on how membership in a self/rater agreement group (underraters, accurate raters, overraters) is related to self‐ratings and others' ratings of self‐awareness and leadership effectiveness. It also examines gender differences in the likelihood of self/rater agreement and in perceived self‐awareness. Finally, the article examines agreement group and gender differences in terms of two components of self‐awareness: knowledge of self and willingness to improve. Contrary to common belief, our research shows that women are not more likely to underrate their own skills on measures of leadership competency, and that gender differences do exist, both in rated self‐awareness and in one of its subcomponents, knowledge of self. In addition, this research found underraters were rated highest in self‐awareness by direct reports and highest in terms of overall leadership effectiveness. Managers who tend to overrate themselves compared to others' ratings were perceived as lowest of the three groups in both self‐awareness and effectiveness. © 1993 by John Wiley & Sons, Inc.
How deficiencies in motivation to manage contribute to the United States' competitiveness problem (and what can be done about it)
Authors: Miner John B. , Ebrahimi Bahman , Wachtel Jeffrey M.
Published: June 2007

Data are presented to support the argument that motivation to manage is a major cause of managerial effectiveness, that it declined sharply in the college population during the activism of the 1960s and early 1970s, and that it is now severely lacking in the United States relative to many other countries. Thus America's competitiveness problems appear to be largely motivational in nature. Possible solutions are discussed, including recruiting and selecting for managerial motivation, increasing motivation to manage using training and development techniques, and changing organizational designs (telescoping the scalar chain, moving managerial tasks into non‐managerial positions, resorting to professional forms, and expanding venture structures). © 1995 by John Wiley & Sons, Inc.
Human resource competencies: An empirical assessment
Authors: Ulrich Dave , Brockbank Wayne , Yeung Arthur K. , Lake Dale G.
Published: June 2007

With data from 12,689 associates of human resource (HR) professionals in 1500 businesses in 109 firms, this research represents an extensive assessment of HR competencies. It extends current HR theory and practice in two ways. First, it proposes specific competencies HR professionals may demonstrate to add value to a business. Second, it offers an empirical assessment of how these competencies affect the performance of HR professionals as perceived by their Associates. The results indicate that when HR professionals demonstrate competencies in business knowledge, delivery of HR, and management of change, then HR professionals are perceived by their associates as more effective. © 1995 by John Wiley & Sons, Inc.
Developing leadership capabilities of global corporations: A comparative study in eight nations
Authors: Yeung Arthur K. , Ready Douglas A.
Published: June 2007

Changing competitive dynamics are influencing the leadership capability requirements of global corporations. More than 1,200 managers from ten major global corporations in eight countries responded to an international survey on the core capabilities required for competitiveness. While the results highlighted six leadership capabilities that are globally valued, a comparative analysis of the data shows that culture affects the relative importance given to a leadership capability requirement. The article also investigates the most effective methods for developing each of the core leadership capabilities. Implications for HR professionals are suggested as they devise strategies for leadership development. © 1995 by John Wiley & Sons, Inc.
Strengthening the weak link in strategic executive development: Integrating individual development and global business strategy
Authors: Seibert Kent W. , Hall Douglas T. , Kram Kathy E.
Published: June 2007

The global business environment of the 1990s provides both challenge and opportunity to human resource development to become an integral player in helping implement business strategy. The results of two best practice studies suggest that some leading firms such as 3M and Motorola are doing just that. At these companies current strategic business issues are the drivers of flexible and opportunistic executive development activities. Naturally occurring on‐the‐job experiences are consciously utilized in such a way that helping executives to develop becomes an integral part of conducting business. The implications of linking executive development to business strategy for practice and for future research are discussed. © 1995 by John Wiley & Sons, Inc.
Neural network modelling for mean velocity and turbulence intensities of steep channel flows
Authors: Chang Fi‐John , Yang Han‐Chung , Lu Jau‐Yau , Hong Jian‐Hao
Published: May 2007

The main purpose of this study is to evaluate the potential of simulating the profiles of the mean velocity and turbulence intensities for the steep open channel flows over a smooth boundary using artificial neural networks. In a laboratory flume, turbulent flow conditions were measured using a fibre‐optic laser doppler velocimeter (FLDV). One thousand and sixty‐four data sets were collected for different slopes and aspect ratios at different locations. These data sets were randomly split into two subsets, i.e. training and validation sets. The multi‐layer functional link network (MFLN) was used to construct the simulation model based on the training data. The constructed MFLN models can almost perfectly simulate the velocity profile and turbulence intensity. The values of correlation coefficient (γ) are close to one and the values of root mean square error (RMSE) are close to zero in all conditions. The results demonstrate that the MFLN can precisely simulate the velocity profiles, while the log law and Reynolds stress model (RSM) are less effective when used to simulate the velocity profiles close to the side wall. The simulated longitudinal turbulence intensities yielded by the MFLN were also fairly consistent with the measured data, while the simulated vertical turbulence intensities by the RSM were not consistent with the measured data. Copyright © 2007 John Wiley & Sons, Ltd.
Applying multifractality and the self‐organized criticality theory to describe the temporal rainfall regimes in Andalusia (southern Spain)
Authors: García‐Marín A. P. , Jiménez‐Hornero F. J. , Ayuso J. L.
Published: May 2007

A multifractal analysis of hourly and daily rainfall data recorded at four locations of Andalusia (southern Spain) was carried out in order to study the temporal structure of rainfall and to find differences between both time resolutions. The results show that an algebraic tail is required to fit the probability distribution of the extreme rain events for all the cases. The presence of a multifractal phase transition associated with a critical moment in the empirical moments scaling exponent function was also detected. Both facts indicate that the rainfall process is a case of self‐organized criticality (SOC) dynamics, although the results differ for each place according to the time resolution and the nature of the rainfall, either convective or frontal. This SOC behaviour is related to a statistically steady state that implies the presence of clusterization in the time‐occurrence sequence of rain events. Such fluctuations have been shown by performing the analysis of the Fano and Allan factors and the count‐based periodogram. The values for the “synoptic maximum”, the typical lifetime of planetary scale atmospheric structures, have been obtained for each place and some important periodicities have been detected when dealing with extremes. Copyright © 2007 John Wiley & Sons, Ltd.
Epstein‐Barr virus latent membrane protein 1 promotes concentration in multivesicular bodies of fibroblast growth factor 2 and its release through exosomes
Authors: Ceccarelli Simona , Visco Vincenzo , Raffa Salvatore , Wakisaka Naohiro , Pagano Joseph S. , Torrisi Maria Rosaria
Published: June 2007

FGF‐2, a potent angiogenic factor that is involved in tumor invasion, is known to be released extracellularly by a nonclassical secretory pathway. Recently it has become clear that Epstein‐Barr virus, specifically its oncoprotein LMP1, can induce expression of angiogenic factors. Among these factors is FGF‐2. LMP1 not only promotes expression of FGF‐2, but also the release extracellularly of its 18‐kDa isoform. We analyzed the mechanism of FGF‐2 release induced by LMP1. Confocal immunofluorescence microscopy revealed colocalization of FGF‐2 with LMP1 in small dots also stained positively for CD63 and cathepsin D, markers of late endosomes or multivesicular bodies. Biochemical analysis and immunoelectron microscopy of purified exosomal fractions from cotransfected cells demonstrated increased release of exosomes and the concentration of LMP1 and FGF‐2 in these structures. Moreover, cotransfection appeared to induce partial redistribution of the Na+/K+‐ATPase, which participates in FGF‐2 release, from the plasma membrane to the intracellular LMP1/FGF‐2 positive dots. Treatment with ouabain, which inhibits Na+/K+‐ATPase activity, partially suppressed FGF‐2 secretion via exosomes in a dose‐dependent manner. The results suggest that exosomes may represent a previously unrecognized mechanism for FGF‐2 release mediated by LMP1, and that this pathway involves the activity of Na+/K+‐ATPase. © 2007 Wiley‐Liss, Inc.
Competing demands for irrigation water: golf and agriculture in Spain
Authors: Diaz J. A. Rodriguez , Knox J. W. , Weatherhead E. K.
Published: June 2007

In many countries where water resources are under stress, there is a perception that irrigating golf courses causes significant additional abstraction, and that this has major impacts on the environment and other abstractors, including irrigated agriculture. This paper provides a quantitative assessment of water use within the golf sector in Spain, and compares it with irrigated agriculture. It is based on literature review, a national survey of golf course irrigation practices, and a correlation of reported irrigation consumption against agroclimate. Using a geographical information system (GIS), the water consumption for all golf courses in Spain was modelled and mapped, and the total water consumption estimated.

The results show that the volume of water used for golf irrigation is extremely small compared to agricultural irrigation. Furthermore, a significant portion comes from wastewater reuse (41%) and desalination (7%), rather than direct abstraction, which competes with agriculture. However, it is concentrated in particular tourist areas and could cause local problems. The average economic productivity of the water used for golf, estimated at around 9 € m−3 in direct benefits (course fees) and 28 € m−3 if including the benefits to the tourist industry, is very much higher than for even high‐value agricultural crops. These results suggest that irrigating golf courses for tourism purposes is an economically rational water use in Spain, even though the transfer of resources from agriculture is controversial. Copyright © 2007 John Wiley & Sons, Ltd.
Cross‐talk between Wnt signaling pathways in human mesenchymal stem cells leads to functional antagonism during osteogenic differentiation
Authors: Baksh Dolores , Boland Genevieve M. , Tuan Rocky S.
Published: June 2007

Wnt signaling is involved in developmental processes and in adult stem cell homeostasis. This study analyzes the role(s) of key Wnt signaling mediators in the maintenance and osteogenesis of mesenchymal stem cells (MSCs). We focus specifically on the involvement of low‐density lipoprotein‐related protein 5 (LRP5), T‐cell factor 1 (TCF1), and Frizzled (Fz) receptors, in the presence or absence of exogenous, prototypical canonical (Wnt3a), and non‐canonical (Wnt5a) Wnts. In undifferentiated MSCs, LRP5 and TCF1 mediate canonical Wnt signal transduction, leading to increased proliferation, enhanced synergistically by Wnt3a. However, LRP5 overexpression inhibits osteogenic differentiation, further suppressed by Wnt3a. Wnt5a does not affect cell proliferation but enhances osteogenesis of MSCs. Interestingly, Wnt5a inhibits Wnt3a effects on MSCs, while Wnt3a suppresses Wnt5a‐mediated enhancement of osteogenesis. Flow cytometry revealed that LRP5 expression elicits differential changes in Fz receptor profiles in undifferentiated versus osteogenic MSCs. Taken together, these results suggest that Wnt signaling crosstalk and functional antagonism with the LRP5 co‐receptor are key signaling regulators of MSC maintenance and differentiation. J. Cell. Biochem. 101:1109–1124, 2007. © 2007 Wiley‐Liss, Inc.
Covering arrays and intersecting codes
Authors: Sloane N. J. A.
Published: June 2007

A t‐covering array is a set of k binary vectors of length n with the property that, in any t coordinate positions, all 2t possibilities occur at least once. Such arrays are used for example in circuit testing, and one wishes to minimize k for given values of n and t. The case t = 2 was solved by Rényi, Katona, and Kleitman and Spencer. The present article is concerned with the case t = 3, where important (but unpublished) contributions were made by Busschbach and Roux in the 1980s. One of the principal constructions makes use of intersecting codes (linear codes with the property that any two nonzero codewords meet). This article studies the properties of 3‐covering arrays and intersecting codes, and gives a table of the best 3‐covering arrays presently known. For large n the minimal k satisfies 3.21256 < k/log n < 7.56444. © 1993 John Wiley & Sons, Inc.
Protein disaggregation and refolding using high hydrostatic pressure
Authors: Phelps David J , Hesterberg Lyndal K
Published: May 2007

Production of recombinant proteins often leads to aggregate formation. These aggregates may make it impossible to solubilize the protein for downstream applications such as assay development or structural studies by X‐ray crystallography or nuclear magnetic resonance spectroscopy. High hydrostatic pressure technology has been developed which offers significant advantages over traditional methods of protein disaggregation and refolding. Pressure induced disruption of protein aggregates and subsequent refolding can take place at high concentrations in a single process step, without the need for high concentrations of chaotropic agents. Copyright © 2007 Society of Chemical Industry
Photocatalytic degradation of dyestuff wastewater under visible light irradiation using micron‐sized mixed crystal TiO2 powders
Authors: Wang Jun , Li Ronghe , Zhang Zhaohong , Zhang Xiangdong , Sun Wei , Wang Hao , Xu Rui , Xing Zhiqiang
Published: May 2007

A phase transformation of micron‐sized TiO2 powder from anatase to rutile was attempted by heat‐treatment in order to generate a new mixed crystal TiO2 with high associated photocatalytic activity. Heat‐treated micron‐sized TiO2 powders at different transition stages were characterized by X‐ray diffraction analysis (XRD), Fourier transform infrared spectroscopy (FT‐IR) and transmission electron microscopy (TEM) methods. The tests of photocatalytic activity of the heat‐treated micron‐sized TiO2 powders were conducted by the photocatalytic degradation of Rhodamine B and Acid Red B under visible light irradiation. The results indicate that mixed crystal TiO2 photocatalyst heat‐treated at 400 °C for 60 min shows the highest photocatalytic activity. It can effectively decompose the Rhodamine B and Acid Red B in aqueous solution after 6 h visible light irradiation. A remarkable improvement in photocatalytic activity of TiO2 is caused by the formation of combined rutile–anatase phases and separation of photogenerated electron–hole pairs. Copyright © 2007 Society of Chemical Industry
Mechanism of naked DNA clearance after intravenous injection
Authors: Liu Feng , Shollenberger Lisa M. , Conwell Christine C. , Yuan Xing , Huang Leaf
Published: May 2007

Background

Injection of naked DNA has been viewed as a safer alternative to current gene delivery systems; however, the rate of clearance from the circulation has been a constant barrier in developing these methods. Naked DNA after intravenous (i.v.) injection will be taken up by the liver and depredated by serum nucleases.

Materials and methods

Our study examines the mechanisms involved in clearance of naked DNA by each compartment, the blood and the liver, in anin vivomouse model. Confocal microscopy and transmission electron microscopy were employed to identify the type of cells taking up DNA and the barrier to DNA access to hepatocytes, respectively.

Results

Our data showed the liver could take up over 50% of 5 µg perfused pDNA, with a maximum 25 µg of pDNA during a single pass, and a slower clearance rate compared to that of liver uptake. It was demonstrated that naked DNA is primarily taken up by the liver endothelial cells and this endothelial barrier to transfection could be overcome by manually massaging the liver, which enlarges the fenestrae.

Conclusions

This study clarifies the mechanism by which naked DNA is eliminated from the circulation after i.v. injection, focusing on the role of both the liver and blood compartmentsin vivo(i.e. mouse). With this knowledge, we can more clearly understand the mechanism of naked DNA clearance and develop more efficient strategies for DNA transferin vivo. Copyright © 2007 John Wiley & Sons, Ltd.
A canonical representation of trivalent hamiltonian graphs
Authors: Frucht Roberto
Published: May 2007

A canonical representation of trivalent hamiltonian graphs in the form of “span lists” had been proposed by J. Lederberg. It is here presented in a modified form due to H. S. M. Coxeter and the author, and therefore called “LCF notation.” This notation has the advantage of being more concise than Lederberg's original span lists whenever the graph has a hamiltonian circuit with rotational symmetry. It is also useful as a method for a systematic classification of trivalent hamiltonian graphs and allows one to define for such graphs two interesting properties, called, respectively, “antipalindromic” and “quasiantipalindromic.”.
On induced subgraphs of a block
Authors: Nebeský Ladislav
Published: May 2007

If G is a block, then a vertex u of G is called critical if G ‐ u is not a block. In this article, relationships between the localization of critical vertices and the localization of vertices of relatively small degrees (especially, of degree two) are studied. A block is called semicritical if a) each edge is incident with at least one critical vertex and b) each vertex of degree two is critical. Let G be a semicritical block with at least six vertices. It is proved that A) there exist distinct vertices u2, v1, u2, and v2 of degree two in G such that u1v1 and u2v2 are edges of G, and u1v2, and u2v2 are edges of the complement of G, and B) the complement of G is a block with no critical vertex of degree two.
The biparticity of a graph
Authors: Harary Frank , Hsu Derbiau , Miller Zevi
Published: May 2007

The biparticity β(G) of a graph G is the minimum number of bipartite graphs required to cover G. It is proved that for any graph G, β(G) = {log2χ(G)}. In view of the recent announcement of the Four Color Theorem, it follows that the biparticity of every planar graph is 2.
Frequently cited publications in pure graph theory
Authors: Berman Gerald
Published: May 2007

This paper is a summary of data derived from a collection of books and papers in pure graph theory and related topics. Tables are included showing most frequently cited authors and publications.
A class of Hamiltonian polytopes
Authors: Goodey P. R.
Published: May 2007

It is shown that any simple 3‐polytope, all of whose faces are triangles or hexagons, admits a hamiltonian circuit.