bluuebunny/crossref_metadata_2025 huggingface dataset:
Slow Inactivation inShakerK Channels Is Delayed by Intracellular Tetraethylammonium
Authors: González-Pérez Vivian , Neely Alan , Tapia Christian , González-Gutiérrez Giovanni , Contreras Gustavo , Orio Patricio , Lagos Verónica , Rojas Guillermo , Estévez Tania , Stack Katherine , Naranjo David
Published: November 2008

After removal of the fast N-type inactivation gate, voltage-sensitive Shaker (Shaker IR) K channels are still able to inactivate, albeit slowly, upon sustained depolarization. The classical mechanism proposed for the slow inactivation observed in cell-free membrane patches—the so called C inactivation—is a constriction of the external mouth of the channel pore that prevents K+ ion conduction. This constriction is antagonized by the external application of the pore blocker tetraethylammonium (TEA). In contrast to C inactivation, here we show that, when recorded in whole Xenopus oocytes, slow inactivation kinetics in Shaker IR K channels is poorly dependent on external TEA but severely delayed by internal TEA. Based on the antagonism with internally or externally added TEA, we used a two-pulse protocol to show that half of the channels inactivate by way of a gate sensitive to internal TEA. Such gate had a recovery time course in the tens of milliseconds range when the interpulse voltage was −90 mV, whereas C-inactivated channels took several seconds to recover. Internal TEA also reduced gating charge conversion associated to slow inactivation, suggesting that the closing of the internal TEA-sensitive inactivation gate could be associated with a significant amount of charge exchange of this type. We interpreted our data assuming that binding of internal TEA antagonized with U-type inactivation (Klemic, K.G., G.E. Kirsch, and S.W. Jones. 2001. Biophys. J. 81:814–826). Our results are consistent with a direct steric interference of internal TEA with an internally located slow inactivation gate as a “foot in the door” mechanism, implying a significant functional overlap between the gate of the internal TEA-sensitive slow inactivation and the primary activation gate. But, because U-type inactivation is reduced by channel opening, trapping the channel in the open conformation by TEA would also yield to an allosteric delay of slow inactivation. These results provide a framework to explain why constitutively C-inactivated channels exhibit gating charge conversion, and why mutations at the internal exit of the pore, such as those associated to episodic ataxia type I in hKv1.1, cause severe changes in inactivation kinetics.
Molecular Template for a Voltage Sensor in a Novel K+ Channel. III. Functional Reconstitution of a Sensorless Pore Module from a Prokaryotic Kv Channel
Authors: Santos Jose S. , Grigoriev Sergey M. , Montal Mauricio
Published: November 2008

KvLm is a prokaryotic voltage-gated K+ (Kv) channel from Listeria monocytogenes. The sequence of the voltage-sensing module (transmembrane segments S1-S4) of KvLm is atypical in that it contains only three of the eight conserved charged residues known to be deterministic for voltage sensing in eukaryotic Kv's. In contrast, the pore module (PM), including the S4-S5 linker and cytoplasmic tail (linker-S5-P-S6-C-terminus) of KvLm, is highly conserved. Here, the full-length (FL)-KvLm and the KvLm-PM only proteins were expressed, purified, and reconstituted into giant liposomes. The properties of the reconstituted FL-KvLm mirror well the characteristics of the heterologously expressed channel in Escherichia coli spheroplasts: a right-shifted voltage of activation, micromolar tetrabutylammonium-blocking affinity, and a single-channel conductance comparable to that of eukaryotic Kv's. Conversely, ionic currents through the PM recapitulate both the conductance and blocking properties of the FL-KvLm, yet the KvLm-PM exhibits only rudimentary voltage dependence. Given that the KvLm-PM displays many of the conduction properties of FL-KvLm and of other eukaryotic Kv's, including strict ion selectivity, we conclude that self-assembly of the PM subunits in lipid bilayers, in the absence of the voltage-sensing module, generates a conductive oligomer akin to that of the native KvLm, and that the structural independence of voltage sensing and PMs observed in eukaryotic Kv channels was initially implemented by nature in the design of prokaryotic Kv channels. Collectively, the results indicate that this robust functional module will prove valuable as a molecular template for coupling new sensors and to elucidate PM residue–specific contributions to Kv conduction properties.
Voltage Dependence of ATP Secretion in Mammalian Taste Cells
Authors: Romanov Roman A. , Rogachevskaja Olga A. , Khokhlov Alexander A. , Kolesnikov Stanislav S.
Published: November 2008

Mammalian type II taste cells release the afferent neurotransmitter adenosine triphosphate (ATP) through ATP-permeable ion channels, most likely to be connexin (Cx) and/or pannexin hemichannels. Here, we show that ion channels responsible for voltage-gated (VG) outward currents in type II cells are ATP permeable and demonstrate a strong correlation between the magnitude of the VG current and the intensity of ATP release. These findings suggest that slowly deactivating ion channels transporting the VG outward currents can also mediate ATP secretion in type II cells. In line with this inference, we studied a dependence of ATP secretion on membrane voltage with a cellular ATP sensor using different pulse protocols. These were designed on the basis of predictions of a model of voltage-dependent transient ATP efflux. Consistently with curves that were simulated for ATP release mediated by ATP-permeable channels deactivating slowly, the bell-like and Langmuir isotherm–like potential dependencies were characteristic of ATP secretion obtained for prolonged and short electrical stimulations of taste cells, respectively. These observations strongly support the idea that ATP is primarily released via slowly deactivating channels. Depolarizing voltage pulses produced negligible Ca2+ transients in the cytoplasm of cells releasing ATP, suggesting that ATP secretion is mainly governed by membrane voltage under our recording conditions. With the proviso that natural connexons and pannexons are kinetically similar to exogenously expressed hemichannels, our findings suggest that VG ATP release in type II cells is primarily mediated by Cx hemichannels.
Modulation of the Local SR Ca2+ Release by Intracellular Mg2+ in Cardiac Myocytes
Authors: Gusev Konstantin , Niggli Ernst
Published: November 2008

In cardiac muscle, Ca2+-induced Ca2+ release (CICR) from the sarcoplasmic reticulum (SR) defines the amplitude and time course of the Ca2+ transient. The global elevation of the intracellular Ca2+ concentration arises from the spatial and temporal summation of elementary Ca2+ release events, Ca2+ sparks. Ca2+ sparks represent the concerted opening of a group of ryanodine receptors (RYRs), which are under the control of several modulatory proteins and diffusible cytoplasmic factors (e.g., Ca2+, Mg2+, and ATP). Here, we examined by which mechanism the free intracellular Mg2+ ([Mg2+]free) affects various Ca2+ spark parameters in permeabilized mouse ventricular myocytes, such as spark frequency, duration, rise time, and full width, at half magnitude and half maximal duration. Varying the levels of free ATP and Mg2+ in specifically designed solutions allowed us to separate the inhibition of RYRs by Mg2+ from the possible activation by ATP and Mg2+-ATP via the adenine binding site of the channel. Changes in [Mg2+]free generally led to biphasic alterations of the Ca2+ spark frequency. For example, lowering [Mg2+]free resulted in an abrupt increase of spark frequency, which slowly recovered toward the initial level, presumably as a result of SR Ca2+ depletion. Fitting the Ca2+ spark inhibition by [Mg2+]free with a Hill equation revealed a Ki of 0.1 mM. In conclusion, our results support the notion that local Ca2+ release and Ca2+ sparks are modulated by Mg2+ in the intracellular environment. This seems to occur predominantly by hindering Ca2+-dependent activation of the RYRs through competitive Mg2+ occupancy of the high-affinity activation site of the channels. These findings help to characterize CICR in cardiac muscle under normal and pathological conditions, where the levels of Mg2+ and ATP can change.
The Timing of Infarction Pain in Patients with Acute Myocardial Infarction after Previous Revascularization
Authors: Mitrovic Predrag M. , Stefanovic Branislav , Vasiljevic Zorana , Radovanovic Mina , Radovanovic Nebojsa , Krljanac Gordana , Rajic Dubravka , Erceg Predrag , Vukcevic Vladan , Nedeljkovic Ivana , Ostojic Miodrag
Published: November 2008

Circadian variation of onset of acute myocardial infarction (AMI) has been noted in many studies, but there are no data about subgroups of patients with previous coronary artery bypass grafting (CABG). Because of abnormalities in the circadian rhythm of autonomic tone after surgery, it was very interesting to analyze the circadian patterns in the onset of symptoms of AMI in various subgroups of 1784 patients with previous CABG. As in the other studies, a peak occurred in the morning hours with 26.3% of the patients, but there was a second nearly equal, but higher, peak (26.4%) in the evening hours. The subgroups with specific clinical characteristics exhibited different patterns that determined these peaks in all populations. In patients older than 70 years of age, in both sexes, in smokers, diabetics, in patients with hypertension, in those undergoing beta-blocker therapy, and in patients without previous angina, two nearly equal peaks were observed, with higher evening peaks, except in those patients with hypertension and without angina. Only one peak in the evening hours was observed in a subgroup of patients with previous congestive heart failure (CHF) and non-STEMI. The subgroup of patients with previous angina and previous AMI exhibited no discernible peaks. The distribution of time of onset within the four intervals was not uniform, and the difference was statistically significant only for patients undergoing beta-blocker therapy at time of onset (p= 0.0013), nonsmokers (p= 0.0283), and patients with non-STEMI (p= 0.0412). It is well known that patients with AMI have a dominant morning peak of circadian variation of onset. However, analyzing a different subgroup of patients with AMI after previous CABG, it was found that some subgroups had two peaks of onset, but a higher evening peak (patients older than 70 years of age, smokers, diabetics, and a group of patients who were taking beta-blocker therapy). This subgroup of patients, together with the subgroups of patients with a dominant evening peak (patients with CHF and those with non-STEMI) and with patients with no peak (patients with previous angina and previous AMI), probably appear to modify characteristic circadian variation of infarction onset, expressing a higher evening peak, respectively to the previous CABG, with adverse consequences for central nervous system functioning.
Decreased Mitochondrial Activities of Malate Dehydrogenase and Fumarase in Tomato Lead to Altered Root Growth and Architecture via Diverse Mechanisms
Authors: van der Merwe Margaretha J. , Osorio Sonia , Moritz Thomas , Nunes-Nesi Adriano , Fernie Alisdair R.
Published: November 2008

Transgenic tomato (Solanum lycopersicum) plants in which either mitochondrial malate dehydrogenase or fumarase was antisense inhibited have previously been characterized to exhibit altered photosynthetic metabolism. Here, we demonstrate that these manipulations also resulted in differences in root growth, with both transgenics being characterized by a dramatic reduction of root dry matter deposition and respiratory activity but opposite changes with respect to root area. A range of physiological, molecular, and biochemical experiments were carried out in order to determine whether changes in root morphology were due to altered metabolism within the root itself, alterations in the nature of the transformants' root exudation, consequences of alteration in the efficiency of photoassimilate delivery to the root, or a combination of these factors. Grafting experiments in which the transformants were reciprocally grafted to wild-type controls suggested that root length and area were determined by the aerial part of the plant but that biomass was not. Despite the transgenic roots displaying alteration in the expression of phytohormone-associated genes, evaluation of the levels of the hormones themselves revealed that, with the exception of gibberellins, they were largely unaltered. When taken together, these combined experiments suggest that root biomass and growth are retarded by root-specific alterations in metabolism and gibberellin contents. These data are discussed in the context of current models of root growth and biomass partitioning.
Kinesins Are Indispensable for Interdigitation of Phragmoplast Microtubules in the MossPhyscomitrella patens
Authors: Hiwatashi Yuji , Obara Mari , Sato Yoshikatsu , Fujita Tomomichi , Murata Takashi , Hasebe Mitsuyasu
Published: November 2008

Microtubules form arrays with parallel and antiparallel bundles and function in various cellular processes, including subcellular transport and cell division. The antiparallel bundles in phragmoplasts, plant-unique microtubule arrays, are mostly unexplored and potentially offer new cellular insights. Here, we report that the Physcomitrella patens kinesins KINID1a and KINID1b (for kinesin for interdigitated microtubules 1a and 1b), which are specific to land plants and orthologous to Arabidopsis thaliana PAKRP2, are novel factors indispensable for the generation of interdigitated antiparallel microtubules in the phragmoplasts of the moss P. patens. KINID1a and KINID1b are predominantly localized to the putative interdigitated parts of antiparallel microtubules. This interdigitation disappeared in double-deletion mutants of both genes, indicating that both KINID1a and 1b are indispensable for interdigitation of the antiparallel microtubule array. Furthermore, cell plates formed by these phragmoplasts did not reach the plasma membrane in ∼20% of the mutant cells examined. We observed that in the double-deletion mutant lines, chloroplasts remained between the plasma membrane and the expanding margins of the cell plate, while chloroplasts were absent from the margins of the cell plates in the wild type. This suggests that the kinesins, the antiparallel microtubule bundles with interdigitation, or both are necessary for proper progression of cell wall expansion.
Property in knowledge work: an appropriation‐learning perspective
Authors: Pinnington Ashly H. , Kamoche Ken , Suseno Yuliani
Published: November 2008

Purpose

The aim of this paper isto understand the competitive and collaborative relations existing between people practising in the same professional occupation, but working within different organisation contexts of employment.

Design/methodology/approach

An interview study of 42 in‐house and external lawyers is reported and set within contexts of the knowledge management and internationalisation of legal services. The data are analysed from an appropriation‐learning perspective and then discussed for the extent that these two groups make similar claims to property in work.

Findings

The in‐house lawyers give highest priority to the protection of resources and knowledge and aim to achieve it through trust in work relationships and by sharing, diffusing and controlling knowledge. By contrast, issues concerning individual reward and empowerment were seen as lower priority. External lawyers attach similar importance to knowledge sharing, its diffusion and control, but have slightly less concern for protecting knowledge and resources. They place less emphasis on trust and seem to value empowerment through legal innovation more so than do the in‐house lawyers.

Research limitations/implications

Future research should be conducted on occupational and sub‐groups of knowledge workers to understand more systematically the dynamics of knowledge management, and the opportunities and constraints it creates for employees' property in work.

Originality/value

The research contributes to the literature on employees' property claims in work. It reflects on the extent that individuals' work identities must systematically adapt to different organisation contexts and approaches to knowledge management.
“Fee earner vs fee burner”: internal divides in law firms
Authors: Forstenlechner Ingo , Lettice Fiona , Tschida Markus
Published: November 2008

Purpose

This article aims to explore and define the implications of the predominant divide in law firms between fee earners, i.e. lawyers contributing to law firm revenue, and support staff, i.e. employees in back office functions not directly contributing to revenue. To identify steps to improve retention rates among support staff.

Design/methodology/approach

A survey was delivered to support staff across four law firms among the top ten UK law firms, out of which 154 valid responses were collected. For the analysis, responses were clustered to identify emerging themes. Additional interviews were also conducted with the aim to clarify emerging themes and deepen understanding of the issues raised.

Findings

“You are either a fee earner or a fee burner” sums up the prevailing attitude support staff experiences in law firms. Throughout the responses – regardless of topic – the divide kept resurfacing again and again. In order to retain and motivate talented support staff, law firms will need to revisit their management of support staff and rethink the management of attitude towards them.

Research limitations

Law firms are just one professional services sector under increasing competitive pressure, other professional service firms with similar structures, such as consulting or accounting firms have not been included in this research.

Practical implications

While support staff ensures the delivery of business critical services in law firms, they are often seen as a disposable cost rather than a business relevant part of the organisation, which leads to frustration and low working morale. Several measures are suggested in this paper to address the management of support staff.

Originality/value

This paper addresses an important gap in our knowledge of law firms and legal profession more generally: The work and working conditions of non‐fee earning staff.
Usability study of digital institutional repositories
Authors: Hee Kim Hyun , Ho Kim Yong
Published: November 2008

Purpose

The purpose of this study is to provide suggestions that could be adapted to improve the usability of institutional repository systems, and to establish a usability evaluation framework, which could be used for heuristic evaluation or formal usability testing of institutional repositories. The study seeks to establishe a usability evaluation guideline based on a literature review.

Design/methodology/approach

Using the evaluation criteria and 30 subjects, the research team administered two usability experiments, laboratory and remote usability tests, and conducted a focus group interview with four experts. Based on the usability evaluation and focus group interview results, the paper proposes ways to improve system usability by showing selected screenshots of the dCollection interface.

Findings

The study shows that an effective provision of directions on how to register and search for documents, improving visual appearance, and clustering and displaying related materials based on the FRBR model is an important task to improve dCollection's usability.

Originality/value

The study establishes a usability evaluation framework for institutional repositories and evaluates the dCollection with the evaluation criteria.
Selective deposition of PEDOT/PSS on to flexible substrates and tailoring the electrical resistivity by post treatment
Authors: Sankir Nurdan D.
Published: November 2008

Purpose

This paper aims to describe two manufacturing techniques for selective patterning of Poly‐3‐4‐ethyleneoxythiophene/poly‐4‐sytrensulfonate (PEDOT/PSS) for flexible electronic applications. The paper also includes methods to tailor the electrical conductivity of the patterned polymeric films.

Design/methodology/approach

Line patterning and inkjet printing methods were used to pattern PEDOT/PSS onto mechanically flexible substrates including polyethylene terephthalate, polyimide and paper.

Findings

PEDOT/PSS thin films with controlled spatial resolution and strong adhesion passing a laboratory Scotch‐tape test were patterned onto flexible substrates using both line patterning and inkjet printing techniques. After annealing, the sheet resistivities of patterned PEDOT/PSS lines increased slightly. Treating the electrodes with ethylene glycol dramatically increased the electrical conductivity.

Research limitations/implications

There has been extensive work on selective deposition of solution processable active materials onto mechanically flexible substrates. Many techniques including line patterning and inkjet printing are currently being used to fabricate devices for flexible electronic applications. However, there is a need for tailoring the electrical conductivity of the patterned polymeric active materials.

Originality/value

In this study, two very cost effective methods for the selective deposition of the water soluble PEDOT/PSS onto flexible substrates with controlled spatial resolution and electrical conductivity are reported.
Educational value of the algebraic numerical methods in electromagnetism
Authors: Freschi Fabio , Giaccone Luca , Repetto Maurizio
Published: November 2008

Purpose

The aim of this paper is to highlight the educational value of algebraic numerical methods with respect to traditional numerical techniques based on differential formulation.

Design/methodology/approach

Algebraic formulations of electromagnetic fields are gaining a new interest in the research community. One common characteristic of these methods is that they impose field equations, for instance charge or mass conservation, directly in algebraic form as a sum of partial contributes, without using differential operators like the divergence one. This feature leads directly to a system of linear equations without requiring any intermediate differential formulation as in finite element method. In addition, these systems of linear equations can be efficiently expressed as a product of matrices related to problem topology and material characteristics.

Findings

Owing to these features, a MATLAB implementation of these theoretical frameworks is particularly efficient and simple and can be used by electrical engineering students which, even if with a basic mathematical background, have a good practice with network theory and its computer implementation. Following this way of thinking, a MATLAB based environment has been created and here it is presented and discussed.

Originality/value

The implementation of the algebraic formulation can be done by using very basic mathematical tools, therefore the algebraic method becomes also a good way to introduce the numerical field analysis to undergraduate students.
Matricial techniques in the analysis of DFB laser structures
Authors: Ferreira Fernandes Carlos Alberto
Published: November 2008

Purpose

The aim of this paper is to develop simulation tools for the analysis of modified structures of distributed feedback (DFB) laser diodes adequate for single longitudinal mode (SLM) operation.

Design/methodology/approach

The paper uses matricial techniques: the transfer matrix method (TMM). When compared to the eigenvalue approach, the matricial techniques are more general and flexible and hence are especially adequate to deal with the analysis and structural design of DFB laser diodes. In this work, the author makes a general description of the TMM, enhancing its importance with some applications by considering the threshold and above‐threshold analysis of a modified DFB laser structure.

Findings

The increasing demands on laser performance, mainly in the area of optical communication systems, have lead to the fabrication of more‐and‐more complex structures. In viewing the development of the associated technology, the importance of the simulation tools revealed of crucial importance.

Originality/value

The simulation model used in this work has been described in other works of the author. In the present analysis a general description of the TMM was implemented, summarizing the results of previous studies for the threshold and above‐threshold regimes of modified DFB laser structures specially designed to show SLM operation.
Nonlinear transformer model in the frequency domain and with symmetrical components
Authors: Degroote Lieven , Vandevelde Lieven , Renders Bert , Gyselinck Johan
Published: November 2008

Purpose

The aim is to develop a nonlinear transformer model to achieve an accurate model to obtain the frequency components of the magnetizing current based on the harmonic voltages at the primary and secondary side. So, it can easily be implemented in a harmonic load‐flow program.

Design/methodology/approach

The transformer model is based on the harmonic balance method. The electric and magnetic equations of the transformer are derived from the electric and magnetic equivalent circuits.

Findings

The transformer model can be easily implemented in a harmonic load‐flow program. The accuracy of the model has been shown by comparing it with a finite element simulation. The transformer model can be used with asymmetrical supply voltages, because different saturation levels of the phases can occur. There is a coupling between the phases which can be concluded out of the asymmetrical currents in the transformer under symmetrical supply voltages.

Research limitations/implications

The transformer model does not consider the iron losses and the interharmonics. In future work the transformer model will be used to study the harmonic losses in distribution networks, so the transformer losses due to these harmonics have to be considered. This can be achieved with a postcalculation process where the magnetic flux density is used to calculate the eddy current losses and the magnetic field intensity will be applied in a static Preisach model to quantify the hysteresis losses.

Practical implications

The model can be used in a harmonic load‐flow program in order to obtain more accurate simulations for the power system analysis and design.

Originality/value

The model presented in this paper is more detailed than similar papers found in literature (saturation of the yokes, coupling between the phases, interaction between different harmonics) and still it takes a brief simulation time.
A new world for virtual reference
Authors: Godfrey Krista
Published: November 2008

Purpose

This paper aims to examine the emerging field of reference in virtual worlds and attempts to determine its place among existing reference services. The virtual world of Second Life is the focus for these virtual world services. Advantages of virtual world reference are highlighted and drawbacks are discussed.

Design/methodology/approach

The paper examines two existing virtual world reference projects in an attempt to determine both the feasibility of virtual world reference and the level of need for such a service.

Findings

Both virtual world reference projects were successful and appear to indicate there is a need for reference within Second Life.

Research limitations/implications

Virtual worlds and reference within these realms are at the very early stages. There is room for detailed analysis of issues raised within the paper.

Practical implications

The paper outlines the steps of creating a collaborative and institutional virtual world reference service, including training and implications.

Originality/value

This paper examines the emerging field of research and practice in virtual worlds and will be of significant interest to reference librarians.
Enable web‐based tracking and guiding by integrating location‐awareness with the world wide web
Authors: Zhou Rui
Published: November 2008

Purpose

The aim of this research is to enable web‐based tracking and guiding by integrating location‐awareness with the Worldwide Web so that the users can use various location‐based applications without installing extra software.

Design/methodology/approach

The concept of web‐based tracking and guiding is introduced and the relevant issues are discussed regarding location‐aware web systems, location determination, location‐dependent content query and personalized presentation. The framework of the web‐based tracking and guiding system – the Web‐Based Guide is proposed, and its prototypical implementation is presented. The main design principles are making use of existing web technologies, making use of available and cheap devices, general‐purpose and lightweight client‐side, and good scalability.

Findings

The paper presents the general‐purpose and modular framework of the Web‐Based Guide, which consists of the Location Server, the Content Server, the Guiding Web Server and the clients which are standard web browsers extended with the Location Control. With such a framework, location‐based applications can offer the services on the web.

Research limitations/implications

The performance of the system should be evaluated and improved, such as the number of the concurrent sessions that the system can sustain, and the workload on the system when in the tracking mode.

Originality/value

The paper proposes a framework for personalized tracking and guiding systems on the web, which can be used in campuses, museums, national parks and so on.
Detection of malicious traffic on back‐bone links via packet header analysis
Authors: John Wolfgang , Olovsson Tomas
Published: November 2008

Purpose

This study seeks to investigate modern internet back‐bone traffic in order to study occurrences of malicious activities and potential security problems within internet packet headers.

Design/methodology/approach

Contemporary and highly aggregated back‐bone data have been analyzed regarding consistency of network and transport layer headers (i.e. IP, TCP, UDP and ICMP). Possible security implications of each anomaly observed are discussed.

Findings

A systematic listing of packet header anomalies, together with their frequencies as seen “in the wild”, is provided. Inconsistencies in protocol headers have been found within almost every aspect analyzed, including incorrect or incomplete series of IP fragments, IP address anomalies and other kinds of header fields not following internet standards. Internet traffic was shown to contain many erroneous packets; some are the result of software and hardware errors, others the result of intentional and malicious activities.

Practical implications

The study not only presents occurrences of header anomalies as observed in today's internet traffic, but also provides detailed discussions about possible causes for the inconsistencies and their security implications for networked devices.

Originality/value

The results are relevant for researchers as well as practitioners, and form a valuable input for intrusion detection systems, firewalls and the design of all kinds of networked applications exposed to network attacks.
The authentication and authorization infrastructure of perfSONAR MDM
Authors: Rodríguez Cándido , Molina Maurizio , Boote Jeff
Published: November 2008

Purpose

The purpose of this paper is to show the results of having a full authentication and authorization scenario in a web service‐oriented architecture. The Joint Research Activity 1 in the EU‐funded GEANT2 project, in cooperation with Internet2, the US Department of Energy's ESnet and the Brazilian National Research and Educational Network, has defined a general framework for a multi‐domain network measurement infrastructure. The implementation, called Performance‐focused Service Oriented Network Monitoring Architecture, contains a set of services delivering performance measurements in a multi‐domain environment. The main goal of this work is to provide a multi‐federation identity solution to perfSONAR.

Design/methodology/approach

This is a case study of applying authentication and authorization standards to a web service‐oriented architecture. The prototype is implemented thanks to eduGAIN.

Findings

A multi‐federation identity solution for highly distributed web services environment has been gained.

Originality/value

The paper shows that it is possible to have a multi‐federated environment for web and non‐web applications applying current technologies. This is useful for practitioners of distributed software, specially in national research and educational networks.
Tomorrow's workplace: a futures approach using prospective through scenarios
Authors: Saurin Ruth , Ratcliffe John , Puybaraud Marie
Published: November 2008

Purpose

The changes now being experienced in the workplace, driven by market pressures, changing demographics and new technologies, are real and accelerating. Since change remains the one constant when it comes to workplace planning, further transformations within the workplace over the next 20 or 30 years can be expected. Hence, this paper aims to demonstrate how to use a scenario planning futures approach in a changing, complex and uncertain workplace environment. As well as provoke thought and discussion about its long‐term future.

Design/methodology/approach

At the Futures Academy in Dublin Institute of Technology, a systematic methodology for exploring and shaping the future has been developed, called the “Prospective through scenario” process. Each stage of the process is discussed in detail throughout this paper, as well as how the process is applied in the Johnson Controls workplace of the future study.

Findings

The creative “futures studies” approach can deal effectively with change, uncertainty and complexity in the workplace environment, by allowing those concerned to think, plan and act proactively rather than reactively as well as provide effective facilities management and real estate strategies.

Practical implications

Real estate organisations need to take the long view, for the greatest risk of our time is being overtaken by inevitable surprises that could have been foreseen and for which we could have been prepared.

Originality/value

Discussion and debate about the future of the workplace is inevitable and futures tools and techniques can facilitate this process.
The Welcoming Workplace: designing for ageing knowledge workers
Authors: Erlich Alma , Bichard Jo‐Anne
Published: November 2008

Purpose

The aim of this paper is to assess the needs of older knowledge workers with implications to the planning and design of office environments for this growing workplace demographic.

Design/methodology/approach

Exploratory, user‐centred research focused on the design of the work environment was undertaken with older knowledge workers in the UK headquarters of a global organisation. A multi‐disciplinary group of designers, architects and applied social researchers utilised an integrated method approach, including interviews, group discussions and design interventions in the workplace.

Findings

Matching the needs of older knowledge workers with the open plan office space, it is found that the workplace provides well for collaboration and teamwork activities, but fails to provide an adequate environment for tasks requiring concentration, ways of working that are alternative to the computer, and rest and recuperation.

Research limitations/implications

The sample of the study is small and based on a “case study” of older workers in one large organisation, and does more to highlight questions and limits the certainty of generalisation. The study has intentionally chosen to limit its inquiry to the experience of older knowledge workers, and therefore can only assume that younger workers may have many of the same needs.

Originality/value

In the context of two major shifts within work, namely, the progressive aging workforce and the move towards a knowledge economy, the study tackles an urgent need to re‐evaluate current office workspace and suggests ways of accommodating it to the requirements of older knowledge workers.
Drilling the LibQUAL+® data for strategic planning
Authors: Stewart Saunders E.
Published: November 2008

Purpose

This paper aims to describe the development of reliable assessment data to support strategic planning among Purdue University Libraries.

Design/methodology/approach

A LibQUAL+® survey was designed to enable the data gathered to be drilled down into by subgroup. Radar charts demonstrated both consistent themes as well as differences in use patterns between the different colleges, and between undergraduates, graduates and faculty. Detailed analysis of the resultant data was then used to support the strategic planning process.

Findings

Subsequent enquiry among the Strategic Planning Group showed that the survey had had a major impact on the process, which led to scrapping of the first draft of the plan, and greatly informed the second draft.

Originality/value

This paper shows the practical applicability of LibQUAL+® data to support strategic planning, replacing hunches and intuitive knowledge about patron opinion with hard facts.
SEC holds round‐table on fair value accounting and auditing standards
Authors: Friedmann Thomas J. , Zacharski Anthony H. , Bancroft Margaret A. , Mulvihill Roger , Reading Susan A. , Williams Robert J. , Rosenblat Alan
Published: November 2008

Purpose

The purpose of this paper is to summarize and analyze the SEC's July 9, 2008 roundtable discussion regarding fair value accounting and auditing standards.

Design/methodology/approach

The paper discusses investor, auditor/accountant/actuary, and corporation views concerning the usefulness of fair value accounting, potential market behavior effects from fair value accounting, challenges in applying fair value standards, possible improvement to the current standards, and working with auditors who provide assurance for fair value accounting.

Findings

Some investor panelists said fair value provides investors with the most current and relevant information of any accounting method and some believe fair valuation is important for market integrity and trust because it is a transparent measure for valuation. Auditors are especially challenged in determining fair values in illiquid or frozen markets. Roundtable participants viewed disclosure as critical for implementation of fair valuation, particularly regarding key inputs and assumptions. Auditors and corporations would like more guidance on applying fair value accounting from the SEC and Public Company Accounting Oversight Board.

Originality/value

The paper provides expert guidance by experienced securities lawyers.
Pleading scienter after Tellabs in Section 10(b) cases generally and in the “subprime” context
Authors: Jacobs Caryn , Strauss Jeffrey M. , Tharp John J. , Agonis Katherine
Published: November 2008

Purpose

The purpose of this paper is to examine the impact the US Supreme Court's Tellabs decision has had on Section 10 (b) cases generally and on cases related to subprime mortgage‐backed securities.

Design/methodology/approach

The paper provides background including provisions of Section 10(b) of the Securities Exchange Act of 1934 and the Private Securities Litigation Reform Act (PSLRA) of 1995. Analyzes the decision in Tellabs, Inc. v. Makor Issue & Rights, Ltd, recent decisions since Tellabs by the the Second, Seventh, and Ninth Circuits, and decisions in two recent subprime securities cases in which defendants moved to dismiss pursuant to Tellabs; and draws preliminary conclusions from cases that have applied Tellabs so far.

Findings

The PSLRA raised the bar for pleading scienter by requiring a “strong inference”, but the courts of appeals have differed in applying the standard. The Tellabs decision asserted that the PSLRA requires consideration of competing inferences in determination of whether scienter is adequately pleaded. The Supreme Court's “prescription” said the inference of scienter must be more than merely “reasonable” or “permissible”; it must seem to a reasonable person to be at least as cogent and compelling as any opposing inference. One lesson of Tellabs and the Seventh Circuit's decision on remand is that the “plausibility” of scienter allegations requires a fact‐specific inquiry. The Ninth Circuit court found that “deliberate recklessness” is sufficient to allege scienter. In one of the subprime cases, In re 2007 Novastar Financial, Inc., a district court found that a deterioration of a company's business was not evidence of wrongdoing. It is difficult – and premature – to draw firm conclusions from cases that have applied Tellabs so far, but requiring courts to consider competing inferences, requiring the pleadings in question to satisfy more “adjectives”, and requiring the “weighing” of inferences at the pleadings stage would all appear to help defendants. However, Tellabs could help plaintiffs by reversing previous practice in which a “tie” between competing inferences automatically resulted in a victory for the defendant.

Originality/value

The paper offers practical guidance by experienced securities lawyers.
ANN and fuzzy logic controller design for hybrid wind/PV system connected to MV distribution grid
Authors: Skretas Sotirios B. , Papadopoulos Demetrios P. , Singh S.N.
Published: November 2008

Purpose

The purpose of this paper is to present a systematic design procedure along with modeling and simulation of a medium‐scale centralized dc‐bus grid connected hybrid (wind turbine (WT) and photovoltaic (PV)) power system (GCHWPPS) for supplying electric power to a three‐phase medium voltage distribution grid.

Design/methodology/approach

The design, modeling, simulation and control of the GCHWPPS are achieved by using Simulink/MATLAB environment.

Findings

The case study shows that the proposed system configuration along with the suggested control schemes achieve rapidly, accurately, stably and simultaneously four objectives, i.e. maximum power point tracking of WT and photovoltaic generator, dc voltage regulation/stabilization at the input of the inverter, and high electric power quality injected into the grid from the inverter, fulfilling all necessary practical interconnection requirements while providing additional load power factor correction.

Originality/value

An effective intelligent dynamic control method is used to a proposed GCHWPPS configuration to simultaneously achieve the four mentioned practical objectives while meeting the grid requirements.
A reflective analysis of the development of a regional workplace health strategy in the North West of England
Authors: Dooris M. , Sedgley L. , Dugdill L.
Published: November 2008

Purpose

This paper sets out to provide an overview of the development processes, key drivers and the impact of a workplace health strategy developed in the North West of England, between 2005 and 2007. The strategy is led by a Regional Workplace Health Co‐ordinator (funded for two years by regional‐level bodies), and is aimed at a broad range of stakeholders across every layer of influence.

Design/methodology/approach

The paper consists of narrative which was co‐constructed by the Guest Editor (third author of the paper) and the co‐authors of the original strategy (first and second authors of the paper). A reflective interview was conducted with the first and second authors, who were interviewed by the third author in the summer of 2008. This interview was transcribed verbatim and then used to co‐construct the paper that follows. The key questions that the narrative was designed to answer were: why and how was the strategy developed? What was the interplay between national and regional levels of the system? What was the value/impact of the strategy?

Findings

The strategy provided an important platform from which regional players could develop actions that would, in the long term, positively influence the health of workers in the region. The scope and breadth of the regional strategy further informed national developments, but its effective delivery within the North West region was seriously hampered by the lack of co‐ordination, governance and ownership. The long‐term impacts of the strategy are not being measured as no funding was available for its evaluation.

Originality/value

Although many workplace health strategies have been developed, few are ever critically evaluated.
The Greek construction sector: an overview of recent developments
Authors: Karousos Evaggelos , Vlamis Prodromos
Published: November 2008

Purpose

The aim of this paper is to present a review of the developments in the Greek construction sector since the year 2000.

Design/methodology/approach

The Greek construction sector – one of the most dynamic sectors of the Greek economy – grew quite strongly over the last decade. The paper follows a rather more descriptive approach to examine and analyse the factors that significantly boosted construction activity in Greece since the year 2000. It also studies and critically analyses the extent to which the Greek macro‐environment (legal‐political, economic, socio‐cultural, technological and demographic), as part of a broader nexus of domestic and global dynamics, affects construction companies.

Findings

The results indicate that the domestic and global macro‐environment have a substantial effect to the market participants in the Greek construction sector. The ability of the Greek construction companies to deal with, and in some cases take advantage of, the constantly changing domestic and global macro‐environment is expected to crucially affect their future viability and success.

Practical implications

This analysis of the Greek construction sector should be useful for industry professionals, policy‐makers and real estate lenders.

Originality/value

To the best of the authors’ knowledge, none of the existing studies in this area provides systematic treatment of the state of the macro‐environment as a contributory factor in explaining the performance of the Greek construction companies. The authors believe that this issue is an important one, especially in the case of industries such as construction, which is prone to cyclical activity.
An estimating method for IP traffic matrix based on generalized inverse matrix
Authors: Shang Fengjun
Published: November 2008

Purpose

The purpose of this paper is to present research in the area of the applications of the generalized inverse matrix in IP traffic matrix.

Design/methodology/approach

Traffic matrices are important for many network design, engineering, and management functions. However, they are often difficult to measure directly. Because networks are dynamic, analysis tools must be adaptive and computationally lightweight. In order to manage the whole network, a novel calculating model is proposed based on the generalized inverse matrix. In this model, a generalized inverse matrix is introduced to resolve the traffic matrix equation. But if so, the error is raised. In order to improve the method, an original traffic matrix is estimated according to the prior, for example, Poisson model. To acquire the optimized solutions, linear programming is introduced. Through both theoretical analysis and simulating results, it is shown that the proposed algorithm achieves better performance than the existing representative methods.

Findings

This paper illustrates the useful information that can be obtained using generalized inverse matrix for incomplete data estimation.

Research limitations/implications

The use of generalized inverse matrix was a very effective method to calculate IP traffic matrix.

Practical implications

The algorithms discussed in the paper can be used to estimate solutions of an ill‐posed linear inverse equation.

Originality/value

The paper is of value in proposing an estimation method for IP traffic matrix using generalized inverse matrix.