bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular mechanisms of experience-dependent plasticity in visual cortex
Authors: Tropea Daniela , Van Wart Audra , Sur Mriganka
Published: November 2008

A remarkable amount of our current knowledge of mechanisms underlying experience-dependent plasticity during cortical development comes from study of the mammalian visual cortex. Recent advances in high-resolution cellular imaging, combined with genetic manipulations in mice, novel fluorescent recombinant probes, and large-scale screens of gene expression, have revealed multiple molecular mechanisms that underlie structural and functional plasticity in visual cortex. We situate these mechanisms in the context of a new conceptual framework of feed-forward and feedback regulation for understanding how neurons of the visual cortex reorganize their connections in response to changes in sensory inputs. Such conceptual advances have important implications for understanding not only normal development but also pathological conditions that afflict the central nervous system.
Cortical mechanisms of sensory learning and object recognition
Authors: Hoffman K.L , Logothetis N.K
Published: November 2008

Learning about the world through our senses constrains our ability to recognise our surroundings. Experience shapes perception. What is the neural basis for object recognition and how are learning-induced changes in recognition manifested in neural populations? We consider first the location of neurons that appear to be critical for object recognition, before describing what is known about their function. Two complementary processes of object recognition are considered: discrimination among diagnostic object features and generalization across non-diagnostic features. Neural plasticity appears to underlie the development of discrimination and generalization for a given set of features, though tracking these changes directly over the course of learning has remained an elusive task.
Chlororespiration and Grana Hyperstacking: How an Arabidopsis Double Mutant Can Survive Despite Defects in Starch Biosynthesis and Daily Carbon Export from Chloroplasts
Authors: Häusler Rainer E. , Geimer Stefan , Kunz Hans Henning , Schmitz Jessica , Dörmann Peter , Bell Kirsten , Hetfeld Sonja , Guballa Andre , Flügge Ulf-Ingo
Published: November 2008

An Arabidopsis (Arabidopsis thaliana) double mutant impaired in starch biosynthesis and the triose phosphate/phosphate translocator (adg1-1/tpt-1) is characterized by a diminished utilization of photoassimilates and the concomitant consumption of reducing power and energy produced in the photosynthetic light reaction. In order to guarantee survival, the double mutant responds to this metabolic challenge with growth retardation, an 80% decline in photosynthetic electron transport, diminished chlorophyll contents, an enhanced reduction state of plastoquinone in the dark (up to 50%), a perturbation of the redox poise in leaves (increased NADPH/NADP ratios and decreased ascorbate/dehydroascorbate ratios), hyperstacking of grana thylakoids, and an increased number of plastoglobules. Enhanced oxygen consumption and applications of inhibitors of alternative mitochondrial and chloroplast oxidases (AOX and PTOX) suggest that chlororespiration as well as mitochondrial respiration are involved in the enhanced plastoquinone reduction state in the dark. Transcript amounts of PTOX and AOX were diminished and nucleus-encoded components related to plastidic NADH reductase (NDH1) were increased in adg1-1/tpt-1 compared with the wild type. Cytochrome b  559, proposed to be involved in the reoxidation of photosystem II, was not regulated at the transcriptional level. The hyperstacking of grana thylakoids mimics adaptation to low light, and increased plastoglobule numbers suggest a response to enhanced oxidative stress. Altered chloroplast organization combined with perturbations in the redox poise suggests that adg1-1/tpt-1 could be a tool for the in vivo study of retrograde signaling mechanisms controlling the coordinated expression of nucleus- and plastome-encoded photosynthetic genes.
Functional Characterization of a Higher Plant Sphingolipid Δ4-Desaturase: Defining the Role of Sphingosine and Sphingosine-1-Phosphate in Arabidopsis
Authors: Michaelson Louise V. , Zäuner Simone , Markham Jennifer E. , Haslam Richard P. , Desikan Radhika , Mugford Sarah , Albrecht Sandra , Warnecke Dirk , Sperling Petra , Heinz E. , Napier Johnathan A.
Published: November 2008

The role of Δ4-unsaturated sphingolipid long-chain bases such as sphingosine was investigated in Arabidopsis (Arabidopsis thaliana). Identification and functional characterization of the sole Arabidopsis ortholog of the sphingolipid Δ4-desaturase was achieved by heterologous expression in Pichia pastoris. A P. pastoris mutant disrupted in the endogenous sphingolipid Δ4-desaturase gene was unable to synthesize glucosylceramides. Synthesis of glucosylceramides was restored by the expression of Arabidopsis gene At4g04930, and these sphingolipids were shown to contain Δ4-unsaturated long-chain bases, confirming that this open reading frame encodes the sphingolipid Δ4-desaturase. At4g04930 has a very restricted expression pattern, transcripts only being detected in pollen and floral tissues. Arabidopsis insertion mutants disrupted in the sphingolipid Δ4-desaturase At4g04930 were isolated and found to be phenotypically normal. Sphingolipidomic profiling of a T-DNA insertion mutant indicated the absence of Δ4-unsaturated sphingolipids in floral tissue, also resulting in the reduced accumulation of glucosylceramides. No difference in the response to drought or water loss was observed between wild-type plants and insertion mutants disrupted in the sphingolipid Δ4-desaturase At4g04930, nor was any difference observed in stomatal closure after treatment with abscisic acid. No differences in pollen viability between wild-type plants and insertion mutants were detected. Based on these observations, it seems unlikely that Δ4-unsaturated sphingolipids and their metabolites such as sphingosine-1-phosphate play a significant role in Arabidopsis growth and development. However, Δ4-unsaturated ceramides may play a previously unrecognized role in the channeling of substrates for the synthesis of glucosylceramides.
Antiquity and Function ofCASTORandPOLLUX, the Twin Ion Channel-Encoding Genes Key to the Evolution of Root Symbioses in Plants
Authors: Chen Caiyan , Fan Cui , Gao Muqiang , Zhu Hongyan
Published: November 2008

Root symbioses with arbuscular mycorrhizal fungi and rhizobial bacteria share a common signaling pathway in legumes. Among the common symbiosis genes are CASTOR and POLLUX, the twin homologous genes in Lotus japonicus that encode putative ion channel proteins. Here, we show that the orthologs of CASTOR and POLLUX are ubiquitously present and highly conserved in both legumes and nonlegumes. Using rice (Oryza sativa) as a study system, we employ reverse genetic tools (knockout mutants and RNA interference) to demonstrate that Os-CASTOR and Os-POLLUX are indispensable for mycorrhizal symbiosis in rice. Furthermore, a cross-species complementation test indicates that Os-POLLUX can restore nodulation, but not rhizobial infection, to a Medicago truncatula dmi1 mutant.
TheArabidopsis onset of leaf death5Mutation of Quinolinate Synthase Affects Nicotinamide Adenine Dinucleotide Biosynthesis and Causes Early Ageing
Authors: Schippers Jos H.M. , Nunes-Nesi Adriano , Apetrei Roxana , Hille Jacques , Fernie Alisdair R. , Dijkwel Paul P.
Published: November 2008

Leaf senescence in Arabidopsis thaliana is a strict, genetically controlled nutrient recovery program, which typically progresses in an age-dependent manner. Leaves of the Arabidopsis onset of leaf death5 (old5) mutant exhibit early developmental senescence. Here, we show that OLD5 encodes quinolinate synthase (QS), a key enzyme in the de novo synthesis of NAD. The Arabidopsis QS was previously shown to carry a Cys desulfurase domain that stimulates reconstitution of the oxygen-sensitive Fe-S cluster that is required for QS activity. The old5 lesion in this enzyme does not affect QS activity but it decreases its Cys desulfurase activity and thereby the long-term catalytic competence of the enzyme. The old5 mutation causes increased NAD steady state levels that coincide with increased activity of enzymes in the NAD salvage pathway. NAD plays a key role in cellular redox reactions, including those of the tricarboxylic acid cycle. Broad-range metabolite profiling of the old5 mutant revealed that it contains higher levels of tricarboxylic acid cycle intermediates and nitrogen-containing amino acids. The mutant displays a higher respiration rate concomitant with increased expression of oxidative stress markers. We postulate that the alteration in the oxidative state is integrated into the plant developmental program, causing early ageing of the mutant.
EFD Is an ERF Transcription Factor Involved in the Control of Nodule Number and Differentiation inMedicago truncatula
Authors: Vernié Tatiana , Moreau Sandra , de Billy Françoise , Plet Julie , Combier Jean-Philippe , Rogers Christian , Oldroyd Giles , Frugier Florian , Niebel Andreas , Gamas Pascal
Published: November 2008

Mechanisms regulating legume root nodule development are still poorly understood, and very few regulatory genes have been cloned and characterized. Here, we describe EFD (for ethylene response factor required for nodule differentiation), a gene that is upregulated during nodulation in Medicago truncatula. The EFD transcription factor belongs to the ethylene response factor (ERF) group V, which contains ERN1, 2, and 3, three ERFs involved in Nod factor signaling. The role of EFD in the regulation of nodulation was examined through the characterization of a null deletion mutant (efd-1), RNA interference, and overexpression studies. These studies revealed that EFD is a negative regulator of root nodulation and infection by Rhizobium and that EFD is required for the formation of functional nitrogen-fixing nodules. EFD appears to be involved in the plant and bacteroid differentiation processes taking place beneath the nodule meristem. We also showed that EFD activated Mt RR4, a cytokinin primary response gene that encodes a type-A response regulator. We propose that EFD induction of Mt RR4 leads to the inhibition of cytokinin signaling, with two consequences: the suppression of new nodule initiation and the activation of differentiation as cells leave the nodule meristem. Our work thus reveals a key regulator linking early and late stages of nodulation and suggests that the regulation of the cytokinin pathway is important both for nodule initiation and development.
Safety risk assessment on communication system based on satellite constellations with the analytic hierarchy process
Authors: Yulong Li , Xiande Wu , Zhongfu Li
Published: November 2008

Purpose

The purpose of this paper is to develop an analytic hierarchy process (AHP) method in safety risk assessment on communication system based on satellite constellations through constructing safety risk index system.

Design/methodology/approach

An empirical study using the AHP was carried out to find the relative weights of those assessment criterion and sub‐objectives of subsystem. Then the risk scores of 15 sub‐objectives and four subsystems were calculated applying the AHP method according to the assessment result of experts.

Findings

According to the overall results from the estimation of experts the safety risk priority of net application is the highest and the safety risk priority of attack on physical equipment is the lowest. This explained that the possibility of a war in today's era, in which peace and development is the theme is very small, and risk prevention should focus more on the defense of network attacks from enemies.

Practical implications

This paper provides a positive analysis of safety risk for a communication system based on satellite constellations and gives an opinion in accordance with the assessment result.

Originality/value

An AHP method was applied in the security risk assessment of communications systems on satellite constellation and the estimation of facing risk situation of the satellite communication system was presented according to the opinion of experts.
Model predictive control approach to global air collision avoidance
Authors: Bousson K.
Published: November 2008

Purpose

Most of the existing approaches for flight collision avoidance are concerned with local traffic alone for which the separation is based on the pairwise analysis of aircraft trajectory trends, which is not efficient with regard to some flight path requirements along waypoints. The purpose of this paper is to deal with the global collision avoidance problem which aims at separating aircraft taking into consideration the global traffic in a given area instead of considering them pairwise. It aims to model the concept of global collision avoidance and propose a validated algorithm for the purpose in the framework of free‐flight.

Design/methodology/approach

The collision avoidance procedure computes online the appropriate speed and heading for each aircraft, at each sampling time‐instant, to generate a collision‐free flight trajectory along scheduled waypoints. The method accounts for automatic assignment of priority indexes that are updated from one control time horizon to the next. The paper considers here the case of aircraft flying at the same altitude, but the proposed method is easily extendable to the general 3D situation. Owing to the predictive features that are inherent to collision avoidance, the collision‐free trajectories are generated using model predictive control approach. A simulation example is presented in the end and its results show the suitability of the proposed approach.

Findings

Since the model predictive control approach is used, the collision avoidance procedure is anticipative; therefore, the avoidance capability depends only on the prediction horizon rather than on the control horizon.

Practical implications

The computation of the trajectory guidance information (speed and heading) at each time‐step is fast, therefore the proposed method is well suited for online processing requirements in real world applications.

Originality/value

The paper provides a flexible modelling framework and a computationally effective algorithm, both based on model predictive control concepts, to cope with global collision avoidance for flight safety enhancement in the framework of free‐flight.
A simulation environment for design and testing of aircraft adaptive fault‐tolerant control systems
Authors: Perhinschi M.G. , Napolitano M.R. , Campa G.
Published: November 2008

Purpose

The purpose of this paper is to present the development of a Matlab/Simulink‐based simulation environment for the design and testing of indirect and direct adaptive flight control laws with fault tolerant capabilities to deal with the occurrence of actuator and sensor failures.

Design/methodology/approach

The simulation environment features a modular architecture and a detailed graphical user interface for simulation scenario set‐up. Indirect adaptive flight control laws are implemented based on an optimal control design and frequency domain‐based online parameter estimation. Direct adaptive flight control laws consist of non‐linear dynamic inversion performed at a reference nominal flight condition augmented with artificial neural networks (NNs) to compensate for inversion errors and abnormal flight conditions following the occurrence of actuator or sensor failures. Failure detection, identification, and accommodation schemes relying on neural estimators are developed and implemented.

Findings

The simulation environment provides a valuable platform for the evaluation and validation of fault‐tolerant flight control laws.

Research limitations/implications

The modularity of the simulation package allows rapid reconfiguration of control laws, aircraft model, and detection schemes. This flexibility allows the investigation of various design issues such as: the selection of control laws architecture (including the type of the neural augmentation), the tuning of NN parameters, the selection of parameter identification techniques, the effects of anti‐control saturation techniques, the selection and the tuning of the control allocation scheme, as well as the selection and tuning of the failure detection and identification schemes.

Originality/value

The novelty of this research efforts resides in the development and the integration of a comprehensive simulation environment allowing a very detailed validation of a number of control laws for the purpose of verifying the performance of actuator and sensor failure detection, identification, and accommodation schemes.
A conception of voice guided general aviation aircraft
Authors: Rogalski Tomasz
Published: November 2008

Purpose

The purpose of this paper is to present the generic conception of the aircraft control system with the voice command interpretation interface. The paper's intention is also to present the first steps of work under control system for general aviation aircraft, which assists pilots using speech interpretation module.

Design/methodology/approach

The paper defines the main rules governing projecting and operating such systems, and defines and discusses the main functionality levels. The use of voice commands for the direct controlling of the flight of the plane is also presented and analyzed in detail.

Findings

The paper presents general rules, which could be applied for work under control systems with speech interpretation modules intended for general aviation aircraft.

Practical implications

The analyses and opinions included in this paper can be generic basis for future projects, which will try to use pilot's voice command to control the general aviation airplane.

Originality/value

This paper presets some conception of the control system with the speech recognition interface. There are main rules generally defining both the structure and the functionality the of such aircraft control system, included in this paper.
Linear and nonlinear simulations of aircraft dynamics using body axis system
Authors: Ozdemir Ugur , Kavsaoglu Mehmet S.
Published: November 2008

Purpose

The purpose of this paper is to present a comparison of nonlinear and linear simulations of aircraft dynamics to determine the divergence of the linear solution from the nonlinear solution.

Design/methodology/approach

The general equations of motion of a transport aircraft are presented both in nonlinear and linear form. The nonlinear equations are solved by using the Runge Kutta method. Linear equations are solved numerically by using the Runge Kutta method and they are also solved exactly by using the Laplace transformation method. All of these solutions are obtained by using the body axis system. The results of the simulations are plotted for different control deflections.

Findings

Solution of linear equations by both methods gave the same results as expected. There are important differences in amplitude and frequency of oscillations which are obtained by using nonlinear and linear equations. These differences increase with growing input control deflection. Therefore, it is appropriate to prefer nonlinear approach to obtain more satisfactory results.

Research limitations/implications

Accurate determination of the aerodynamic derivatives is important for the accuracy of the nonlinear solutions.

Originality/value

Many classical approaches use stability axis system for the solution of linear equations. However, in this paper transfer functions of the aircraft are redefined in the body axis system, because stability axes change with angle of attack and some of the stability derivatives need to be re‐evaluated for each angle of attack. Moreover, in addition to classical text book, linear equations are also solved by using the 4th order Runge Kutta medhod.
A knowledge‐based conflict resolution tool for en‐route air traffic controllers
Authors: Özgür Metin , Cavcar Aydan
Published: November 2008

Purpose

The purpose of this paper is to develop a knowledge‐based decision support tool used for assisting en‐route air traffic controllers by generating resolutions for dual aircraft conflicts after being integrated into a model‐based conflict detection and conflict resolution system.

Design/methodology/approach

Air traffic controller knowledge, which was obtained from the literature research, about solving aircraft conflicts is represented in a decision tree. Then it is written in Visual Basic programming language. With reference to several rules form the expert air traffic controller knowledge and some factors which affect controller conflict resolution process, the tool generates advisories consisting of eight kinds of separation strategies.

Findings

The paper finds that it is expected to increase the safety of air traffic system by supporting air traffic controller in conflict resolution process. Controller workload can be reduced by fast, reliable and acceptable resolution advisories of the tool.

Research limitations/implications

The accuracy of decision tree is limited with the adequacy and quality of knowledge obtained from references, several assumptions and interpretation. Because of the unavailability of a model‐based conflict detection and resolution tool, the tool could not be evaluated in simulations.

Originality/value

After being integrated into a model‐based decision support tool, it can reduce the deficiencies of the model‐based tool such as low degree of resolution acceptance by controllers and low‐resolution speed by providing expert air traffic controller knowledge to the tool.
Comparison of turbulence methods in CFD analysis of compressible flows in radial turbomachines
Authors: Aghaei tog R. , Tousi A.M. , Tourani A.
Published: November 2008

Purpose

The purpose of this paper is to show the superior turbulence method in CFD analysis of radial turbo machines and to introduce the best way to choose turbulence parameters whenever FLUENT user applies this software as a complementary design tool for high‐speed turbo machinery components.

Design/methodology/approach

One of the most important issues in CFD is analysis of flow field in turbo machines. Flow in high‐speed radial turbo machinery is a 3D, turbulent and unsteady behavior so needs suitable method for converging. It is clear that the turbulence model has an extraordinary effect on investigation of 3D flows in high‐speed turbo machinery. A centrifugal compressor of micro and radial turbines have been designed and simulated 3D using the commercial CFD‐code FLUENT 6. Three turbulence models k‐ε/standard, renormalization‐group (RNG) and RSM were considered and results of three models were compared with experimental and 1D design results.

Findings

The study showed numerical results are compatible with experimental performance data. It determined that RNG method in CFD analysis of radial turbo machines has provided better results than the standard k‐ε method. In addition, when using the RNG method, the phenomena of flow field were more visible than other methods.

Originality/value

This paper offers use of the RNG method as a superior turbulence method in CFD analysis of radial turbo machines.
The microbiological quality of stuffed mussels (Midye Dolma) sold in Istanbul
Authors: Baris Bingol Enver , Colak Hilal , Hampikyan Hamparsun , Muratoglu Karlo
Published: November 2008

Purpose

This study was performed to determine the microbial quality of stuffed mussels and to discuss the microbiological quality criteria of ready‐to‐eat (RTE) foods defined in the Turkish Food Codex (TFC).

Design/methodology/approach

Stuffed mussel (Midye Dolma), which can be classified as RTE foods, made from mussel and rice, cooked separately then put together in the shell, is commonly consumed in Turkey. This special food might be an important source of microorganisms especially pathogen bacteria because of preparation and serving process. During the period of March‐October 2006, a total of 168 stuffed mussel samples were collected randomly from restaurants, buffets and street sellers located in Istanbul and analysed some microbiological parameters.

Findings

Coliforms were detected in 130 (77.38 per cent), Escherichia coli in 37 (22.02 per cent), Staphylococcus aureus in 40 (23.80 per cent), Bacillus cereus in 65 (38.69 per cent), yeast and moulds in 147 (87.50 per cent) and sulphite‐reducing anaerob bacteria in 61 (36.30 per cent) stuffed mussel samples, respectively. Total aerobic bacteria count (TAB) was between 1.0 × 102 and 3.2 × 107 CFU/g. No Salmonella spp. was detected in analysed samples.

Originality/value

This is the first comprehensive study to provide information on the microbiological quality of stuffed mussels sold in Istanbul, Turkey. This information is important in the determination of measures that can be taken to control the safety of these cooked or prepared foods.
Farm assurance schemes: can they improve farming standards?
Authors: Anne Lewis Kathleen , Tzilivakis John , Green Andrew , Warner Douglas , Coles Adele
Published: November 2008

Purpose

The purpose of this paper is to consider the global activities, highlighting the UK, concerned with farm assurance schemes and associated food labelling seeking to identify their contribution towards improving primary production standards.

Design/methodology/approach

A desk study focusing on published literature and historical documentation.

Findings

The majority of primary production standards are based upon codes of good practice with only tenuous links between the standards and the required environmental outcomes. Owing to the difficulties of comparing like with like here is little conclusive evidence that such standards are producing environmental benefits.

Practical implications

If it depends on assurance schemes to improve farming practices then a European‐wide standard is required that is not compromised by variations in national laws and codes of practice.

Originality/value

This review is of academic value and of value to those working to improve primary production standards. It presents arguments for introducing environmental outcome based measures into the UK assurance schemes.
Consumer concerns about food and health
Authors: Worsley Anthony , Lea Emma
Published: November 2008

Purpose

Aims to investigate the relationships between consumers' food concerns and their personal values and demographic characteristics.

Design/methodology/approach

A questionnaire was administered in a cross sectional random population survey conducted among a sample of 1,000 adults in South Australia. The questionnaire elicited information about respondents' concerns about 20 food and health issues, the perceived importance of 23 values items derived from the Schwartz values inventory, and their demographic characteristics.

Findings

Principal components analyses derived four food concerns factors and six personal values factors. Respondents' safety concerns scores were positively associated with devout‐tradition, order‐discipline, and moderate‐independent values. Their disease concerns score was positively linked to beauty‐nature, devout‐tradition, and order‐discipline. Multiple regression and chi‐square automatic interaction detection (CHAID) analyses showed that individual values items were strong predictors of consumers; specific concerns such as food and heart disease, and, genetic modification of foods.

Research limitations/implications

The research was based on a cross sectional study. More refined indices of food concerns and personal values should be used in replications of this preliminary study.

Practical implications

The findings support the use of psychographic market segmentation approaches in communication programs about food and health issues.

Originality/value

The findings suggest that personal values, may be stronger predictors of consumers' concerns about food and health issues than demographics. They also show that measurement level of values and concerns influence the observed strength of their relationships.
A systematic review of the association between cardiovascular risk factors and regular consumption of oats
Authors: Ruxton C.H.S. , Derbyshire E.
Published: November 2008

Purpose

To review the evidence from high quality human intervention studies that reported links between oat consumption and cardiovascular disease (CVD) risk factors.

Design/methodology/approach

Using Medline, a search was made for all randomized controlled trials published between 1990 and 2008 that met defined inclusion criteria. Studies had a minimum duration of 14 days, used oat products rather than purified extracts, and included plasma lipid levels as outcome variables.

Findings

A total of 21 eligible studies were located 13 of which reported significant reductions in total cholesterol when oats were consumed, while 14 reported significant reductions in low‐density lipoprotein cholesterol. A few studies found increases in high‐density lipoprotein cholesterol and more favourable cholesterol ratios when oats were consumed.

Research limitations/implications

It was not possible to analyse differences in response between health and “at risk” subjects. A meta‐analysis would be a useful step forward, as would research on the long‐term impact of oats on body weight.

Practical implications

Intakes of oats in successful intervention studies were impractical for most consumers. However, expert bodies base approved health claims on an achievable 3 g β‐glucan per day. Additional research on portion sizes for commercially‐available foods would increase consumer awareness of how to access the cholesterol‐lowering benefits of oats. Effective portion sizes may differ by gender, age and CVD risk.

Originality/value

This review provides further evidence that regular oat consumption is an effective dietary strategy for helping to attenuate CVD risk and sets this within the context of claims for food stuffs.
Functional foods: a conceptual definition
Authors: Doyon Maurice , Labrecque JoAnne
Published: November 2008

Purpose

To draw the frontiers of the functional food universe, to identify concepts that should be included in a broadly accepted functional food definition and to propose a definition.

Design/methodology/approach

Based on a review of the literature and the Delphi technique with a group of North American and European experts.

Findings

Four concepts were identified: the nature of food, health benefits, functions and regular consumption. Two dimensions, physiological effects and functional intensity, were developed to define the frontiers of the functional food universe and a definition is suggested.

Practical implications

A large number of definitions as well as great variations within definitions make it difficult to provide industry partners with robust information on market trends and market potential, or to appropriately protect consumers through legislation. This paper should contribute to the debate surrounding the type of food that should be considered a functional food and surrounding the lack of a common definition for functional foods.

Originality/value

This paper is the first one, to our knowledge, that attempts to conceptually define the frontiers of the functional food universe and to provide a definition of functional food which is not sensitive to cultural differences, can accommodate temporal variations and rely on previous knowledge (definition) as well as experts' opinions.
Marketing olive oil in Greece
Authors: Blery Evangelia , Sfetsiou Eugenia
Published: November 2008

Purpose

The purpose of this paper is to examine the issues related to the promotion and marketing of olive oil, by the Greek company Minerva S.A. Thus, the product, its target market and competition are examined, a SWOT analysis is performed and the marketing mix is presented.

Design/methodology/approach

Since the aim of this study was to examine the marketing practices of the company Minerva S.A., the case study method was preferred because its fundamental characteristic is the “focus on a particular setting or event”.

Findings

The findings showed that the company offers high quality products in good prices and is a market leader. However, it faces severe competition. The company advertises its olive oil products and conducts intense promotional campaigns to promote them in the local market and abroad. Exports are a good opportunity to increase sales.

Originality/value

This paper is one of the few that have examined the promotion and marketing of olive oil worldwide and it is one of the very few that have examined such issues in the Greek market, where little research has taken place in this sector. Thus, it can give an important insight in the olive oil sector and become a useful tool for managers in this sector.
Work and work roles: a context of tasks
Authors: Huvila Isto
Published: November 2008

Purpose

Both task‐based and work‐oriented research approaches have proved their value in information science research. A task is a workable analytical unit of human activity, which brings the level of explication close enough to cater for individual actions and their consequences. Similarly, work and work roles have been effective concepts at explicating the broad patterns of professional information activity. Major issues of the existing approaches are the difficulty of conceptualising the contexts of tasks and the relatively high level of abstraction of a work level scrutiny. The purpose of this paper is to discuss how the concepts of “work”, “work role” and “task” might be integrated into a common research agenda. It is suggested that the explication of work and work roles might serve in providing additional understanding on the formation of the purposes, meanings and values, which guide the shaping of the activities conceptualised as tasks.

Design/methodology/approach

The issue is discussed in general with a reference to an empirical study of information work of archaeology professionals informed by the notion of work role.

Findings

It is suggested that the broader notions of work and work roles are useful concepts for explicating the context of more specific tasks.

Research limitations/implications

The suggested approach brings together task and work–work role‐based research and provides a basis for exploring human information activity from a broader perspective than before and thus improving the general understanding of why and how information is used as it is used.

Practical implications

The study provides an approach to conceptualise the ways how people work with information and lays the ground for improving information management and organisation practices.

Originality/value

There has been little prior discussion about integrating the task and work‐based approaches. The paper suggests that the explication of work and work roles might serve in providing additional understanding on the formation of the purposes, meanings and values, which guide the shaping of the activities conceptualised as tasks.
Comparison and evaluation of the user interfaces of e‐journals II: perceptions of the users
Authors: Vilar Polona , Žumer Maja
Published: November 2008

Purpose

The paper aims to present a part of a wider study, performed at the Department of LIS&BS at the University of Ljubljana (UL). The study investigated the perceptions of user friendliness of information retrieval (IR) systems.

Design/methodology/approach

An expert study and a user study were performed. The user study was based on the results of the previous expert study, which surveyed the interfaces of four e‐journal IR systems (Science Direct, Proquest Direct, Ebsco Host and Emerald) and has been published separately. In the user study three of these interfaces were used: Science Direct, Proquest Direct, and Ebsco Host. A pilot study with ten subjects and a main study with 61 subjects, all postgraduate students of the UL, was performed. Questionnaires and observation were used for data collection. The users' perceptions of user interfaces were investigated and compared to the findings of the expert study.

Findings

It was found that users do not show high appreciation of auxiliary functions (such as search history, indexes, etc.) and do not use them to a great extent. They also do not prefer to have available different full‐text formats. Perceptions of user friendliness of elements and functions were different in each interface. For each interface it was also established that different functions and elements were influential in the overall perceptions of the interface friendliness. In comparison of the findings of the expert and user study it was found that the expert study was in some cases too detailed and investigated aspects not perceived by the users. For this reason, certain findings of both studies were not appropriate for comparison.

Research limitations/implications

The methodology of data collection was rather demanding and lengthy, and influenced the type and size of sample. Because of that it may not be possible to generalise the result to all users of e‐journals. Also, large quantities of data were collected which could be studied further.

Practical implications

The results of the study are relevant for the design of the user interfaces of IR systems. They also have implications for other areas, e.g. user education and training.

Originality/value

The study investigates the users' own perceptions of user friendliness of the e‐journal interfaces and also compares them to the findings of the expert study. This gives a valuable insight and provides many different viewpoints in regard to user friendliness, which in itself is a demanding concept.
Using classification schemes and thesauri to build an organizational taxonomy for organizing content and aiding navigation
Authors: Wang Zhonghong , Sattar Chaudhry Abdus , Khoo Christopher S.G.
Published: November 2008

Purpose

Potential and benefits of classification schemes and thesauri in building organizational taxonomies cannot be fully utilized by organizations. Empirical data of building an organizational taxonomy by the top‐down approach of using classification schemes and thesauri appear to be lacking. The paper seeks to make a contribution in this regard.

Design/methodology/approach

A case study of building an organizational taxonomy was conducted in the information studies domain for the Division of Information Studies at Nanyang Technology University, Singapore. The taxonomy was built by using the Dewey Decimal Classification, the Information Science Taxonomy, two information systems taxonomies, and three thesauri (ASIS&T, LISA, and ERIC).

Findings

Classification schemes and thesauri were found to be helpful in creating the structure and categories related to the subject facet of the taxonomy, but organizational community sources had to be consulted and several methods had to be employed. The organizational activities and stakeholders' needs had to be identified to determine the objectives, facets, and the subject coverage of the taxonomy. Main categories were determined by identifying the stakeholders' interests and consulting organizational community sources and domain taxonomies. Category terms were selected from terminologies of classification schemes, domain taxonomies, and thesauri against the stakeholders' interests. Hierarchical structures of the main categories were constructed in line with the stakeholders' perspectives and the navigational role taking advantage of structures/term relationships from classification schemes and thesauri. Categories were determined in line with the concepts and the hierarchical levels. Format of categories were uniformed according to a commonly used standard. The consistency principle was employed to make the taxonomy structure and categories neater. Validation of the draft taxonomy through consultations with the stakeholders further refined the taxonomy.

Originality/value

No similar study could be traced in the literature. The steps and methods used in the taxonomy development, and the information studies taxonomy itself, will be helpful for library and information schools and other similar organizations in their effort to develop taxonomies for organizing content and aiding navigation on organizational sites.
Do libraries matter? Public libraries and the creation of social capital
Authors: Vårheim Andreas , Steinmo Sven , Ide Eisaku
Published: November 2008

Purpose

Librarians and the library profession keep repeating that libraries contribute greatly to generating social capital by “building community”. However, little evidence of this has been presented. This paper aims to be a first step towards correcting this situation by asking whether public libraries matter in the creation of generalized trust.

Design/methodology/approach

This study used quantitative data in analyzing macro‐level data on whether public library expenditure could explain social trust patterns in the OECD countries. Additionally, a few qualitative interviews with public library leaders in the USA and Norway were used to indicate by what mechanisms, or by which processes, libraries generate generalized trust.

Findings

The main finding is that public libraries seem the most important factor in creating generalized trust in the OECD area, even more so than efficient/impartial public institutions. However, there is the problem of causal direction. It might be the case that it is high trusting countries that prioritize public libraries. Therefore, times series data are needed as well as qualitative data on the process of trust creation in the library. Interviews with library leaders point towards the fact that they see outreach activities as creating trust and that people trust the library. Replication of these results, however, is crucial. Moreover, the findings appear to indicate that when the library's attention is directed at disadvantaged groups of non‐users it is the widespread trust in the public library institution that breeds trust among these groups too.

Originality/value

The paper contributes to the understanding/theory of the creation of generalized trust in general and to the role of the public library in this process.
A critical review of research on information behavior in assigned learning tasks
Authors: Tanni Mikko , Sormunen Eero
Published: November 2008

Purpose

This paper aims to give a critical review of the empirical information seeking and retrieval (IS&R) literature focusing on learning related information behavior. It also aims to propose the task‐based approach to link research on learning and information behavior in learning tasks and to organize and interpret the literature.

Design/methodology/approach

This paper takes the form of a critical literature review.

Findings

Researchers have identified patterns of information behavior and variations in the conceptions of seeking and using information for learning tasks. The results are fragmented and a framework should be developed to guide further research. Learners' information behavior in learning tasks may be attributable to various explanatory factors, which have not been taken into account in any single study. The concept of focus formulation appears to link information seeking and learning. The role of the writing process in learners' information behavior and the characteristics of the resulting documents have received least attention in the research field.

Research limitations/implications

The review emphasizes task‐based IS&R literature. Learning research may shed more light on specific questions.

Practical implications

The paper may help teachers in designing learning tasks.

Originality/value

The paper provides a synthesis of recent studies on information behavior in learning tasks and identifies new paths for further research.
The retrieval effectiveness of web search engines: considering results descriptions
Authors: Lewandowski Dirk
Published: November 2008

Purpose

The purpose of this paper is to compare five major web search engines (Google, Yahoo, MSN, Ask.com, and Seekport) for their retrieval effectiveness, taking into account not only the results, but also the results descriptions.

Design/methodology/approach

The study uses real‐life queries. Results are made anonymous and are randomized. Results are judged by the persons posing the original queries.

Findings

The two major search engines, Google and Yahoo, perform best, and there are no significant differences between them. Google delivers significantly more relevant result descriptions than any other search engine. This could be one reason for users perceiving this engine as superior.

Research limitations/implications

The study is based on a user model where the user takes into account a certain amount of results rather systematically. This may not be the case in real life.

Practical implications

The paper implies that search engines should focus on relevant descriptions. Searchers are advised to use other search engines in addition to Google.

Originality/value

This is the first major study comparing results and descriptions systematically and proposes new retrieval measures to take into account results descriptions.
Legal issues for information professionals IX
Authors: Oppenheim Charles
Published: November 2008

Purpose

This paper aims to provide an update to the last major review by Burrull and Oppenheim of legal aspects of information management in relation to the web.

Design/methodology/approach

The paper reports developments in the primary areas of law in relation to the internet since 2004. Topics covered include: copyright, domain names and trademarks, linking, framing, caching and spamdexing (the use of artificial means to enhance one's position in search engines' outputs), patents, censorship, defamation, liability, conflict of laws and jurisdiction and legal deposit.

Findings

The paper shows that legal issues surrounding the internet are likely to become increasingly difficult and that either a new system is needed to resolve disputes, or that a new body of law is needed. It also suggests that information professionals need to contribute more to the ongoing legal debate.

Originality/value

The paper systematically describes legal issues associated with the management of electronic information.
Investigation of dietary intake and obesity status in a pediatric population from Northern Greece
Authors: Papandreou Dimitrios , Malindretos Pavlos , Rousso Israel
Published: November 2008

Purpose

The aim of this study is to record the prevalence of overweight and obesity and to explore any relationship with nutritional status in Greek children aged 6‐15 years.

Design/methodology/approach

A total of 524 children participated in the study. Anthropometric and dietary characteristics were recorded for all subjects.

Findings

The prevalence of overweight and obesity was 21.1 per cent and 8.4 per cent for boys and 17.6 and 7.3 per cent for girls, respectively. Dietary intakes of energy, fat, protein, lipids and sugar were higher in overweight and obese children compared with the normal ones ( p < 0.001), while fibre intake was lower in the overweight and obese group ( p < 0.001) than in the normal group. The current study gives an estimation of overweight and obesity in children from Northern Greece. The composition of diet, especially low in fibre, vitamin D and high in energy and fat may play a role in the etiology of obesity.

Originality/value

The paper presents information on obesity prevalence in a Mediterranean country as well as integration of some nutrients in the etiology of obesity.