bluuebunny/crossref_metadata_2025 huggingface dataset:
Market value and depreciated replacement cost: contradictory or complementary?
Authors: French Nick , Gabrielli Laura
Published: August 2007

Purpose

In January 2005, the International Valuation Standards Committee (IVSC) published the International Valuation Guidance Note No. 8 entitled The Cost Approach for Financial Reporting – (DRC). This guidance note provides background to the use of depreciated replacement cost (DRC) in connection with International Valuation Application 1 (IVA 1), Valuation for Financial Reporting and suggests that the valuer reports the result of a DRC valuation as market value subject to the test of adequate profitability or service potential. This suggestion has caused a lot of debate and consternation in the UK where the DRC approach has always been considered as a method of last resort and not a market valuation. However, in continental Europe the cost approach (DRC) is often the principal method of valuation and has always been considered to produce market value. The purpose of this paper is to discuss the impact of this change to valuation practice in the UK.

Methodology/design/approach

In this paper, we discuss the concept of market value and its relationship to DRC in an attempt to identify the principal areas of concern in the UK and, through the use of an Italian case study, show how the DRC approach can be adopted as an appropriate method (not basis) for calculating Market Value.

Findings

It is probable that most valuers will still provide the DRC valuation using exactly the same calculation as they did before. They are likely to provide the same (relative to the valuation date) figure; the difference is that they will feel less easy about the robustness of that figure

Originality/value

It is argued that the UK market has, for too long, hidden behind DRC being a basis of value that UK valuers now feel uncomfortable in reporting DRC as market value. They are uncertain with the valuation figure. However, this uncertainty can be addressed in other ways and a suggested “solution” to help the valuer overcome their discomfort with the market valuation is proffered.
The dimensionality of customer privacy concern on the internet
Authors: Castañeda J. Alberto , Montoso Francisco J. , Luque Teodoro
Published: August 2007

Purpose

This study attempts to carry out an approximation both to the conceptual delimitation and to the measuring of customer concern for privacy on the electronic market.

Design/methodology/approach

To complete the objective of this research, an overview of the literature is made in an attempt to summarise the main proposals as regards dimensions of the construct analysed. Furthermore, two studies were carried out with the aim of evaluating the instruments to measure concern for privacy on the internet and which support the conclusion concerning the construct's dimensionality, reached following the aforementioned literature overview.

Findings

From the main results reached, we can highlight that the concern for privacy on the internet construct has a structure consisting of two dimensions, which are confirmed through the scales evaluated for different contexts of use of the internet. These dimensions are: concern for control over the collecting of personal information, and its use on the electronic market.

Originality/value

The paper's main contributions are threefold: a conceptual revision of the construct; a proposal of the dimensions for the construct; and an evaluation of two scales to measure the construct in different situations.
Multiple language supports in search engines
Authors: Zhang Jin , Lin Suyu
Published: August 2007

Purpose

This paper aims to investigate the multiple language support features in internet search engines. The diversity of the internet is reflected not only in its users, information formats and information content, but also in the languages used. As more and more information becomes available in different languages, multiple language support in a search engine becomes more important.

Design/methodology/approach

The first step of this study is to conduct a survey about existing search engines and to identify search engines with multiple language support features. The second step is to analyse, compare, and characterise the multiple language support features in the selected search engines against the proposed five basic evaluation criteria after they are classified into three categories. Finally, the strengths and weaknesses of the multiple language support features in the selected search engines are discussed in detail.

Findings

The findings reveal that Google, EZ2Find, and Onlinelink respectively are the search engines with the best multiple language support features in their categories. Although many search engines are equipped with multiple language support features, an indispensable translation feature is implemented in only a few search engines. Multiple language support features in search engines remain at the lexical level.

Originality/value

The findings of the study will facilitate understanding of the current status of multiple language support in search engines, help users to effectively utilise multiple language support features in a search engine, and provide useful advice and suggestions for search engine researchers, designers and developers.
Making organizational change stick: leadership reality checks
Authors: Longenecker Clinton O. , Rieman Melissa L.
Published: August 2007

Purpose

With organizations trying to compete on a global scale, they are constantly putting energy and resources into performance improvement and change initiatives. The purpose of this research is to make it clear that sustaining performance improvement and making change stick is a truly challenging component for most enterprises.

Design/methodology/approach

The paper identifies three key factors that have strong implications on development and learning in organizations dealing with this subject. This paper discusses how to make sure that improvement is real, avoiding declaring success prematurely and leading so as to make change stick.

Findings

The paper discusses the factors and from these are found some specific actions for business leaders serious about real change and improvement.

Originality/value

The paper provides useful information for business leaders who are serious about real change and improvement.
Experiential learning – its place in in‐house education and training
Authors: Valkanos Efthymios , Fragoulis Iosif
Published: August 2007

Purpose

Intense competition, rapid technological changes and modern aspects of management force any enterprise to put emphasis on their personnel and invest in their training and education. In terms of in‐house education and training, experiential learning is chosen to be analyzed in this particular paper. The paper aims to present experiential methods developed by trainers during the process of carrying out in‐house training programs with the aim of motivating trainees to learn through participative experiences and simultaneously adopt for their part another way of thought, action or behavior. It also seeks to examine the reasons why experiential learning is important and the conditions under which this kind of knowledge can be effective.

Design/methodology/approach

The paper presents a general review of a range of experiential learning methods.

Findings

The paper results in a useful checklist for developers and trainers to assess the level of experiential learning they are currently offering.

Originality/value

The paper provides definitions of the three types of experiential learning and identifies the key reasons for including these types of developmental activities in any trainers portfolio of approaches.
Longitudinal textual analysis: an innovative method for analysing how realised strategies evolve
Authors: Langley A. , Kakabadse N. , Swailes S.
Published: August 2007

Purpose

This paper aims to present an innovative methodological framework developed out of primary research that will lead to new understanding about patterns in the strategic actions realised by firms within an industry. The framework is to be applied to increase understanding of how realised strategies evolved in the pharmaceutical industry and overcomes some of the limitations of other methods.

Design/methodology/approach

A qualitative approach was developed adapting techniques from text, thematic and content analysis to identify and categorise strategic actions realised by pharmaceutical firms (referred to as grand strategies). Strategic actions were not pre‐selected but allowed to emerge during the data collection process from public announcements by firms in the industry's main journal,Scrip. Building upon the work of Pearce and Robinson grand strategies can be understood as the packages of strategic actions that firms had planned and/or realised in order to achieve long‐term objectives.

Findings

A framework of realised strategic actions and grand strategies in the pharmaceutical industry was developed with 23 mutually exclusive categories. The paper shows how the framework can be used as an analytical tool to explore patterns in strategic action and grand strategy evolution, temporal patterns in strategy development and strategic action coevolution.

Research limitations/implications

A limitation of the categorisation is that it is based on material collected from two years of empirical data fromScripin order to develop the methodological framework. The framework was applied to data collected over an 11 year period in order to explore how the strategic actions of individual firms had evolved and co‐evolved. Data sources were limited to published sources.

Originality/value

The qualitative approach presented here offers a level of depth that has not been achieved by methodological approaches previously used to explore and compare patterns in realised strategic actions by firms operating in the pharmaceutical industry. The innovative approach contributes to management research in two key ways: providing a methodological framework that overcomes the limitations of previous studies into strategy evolution; and providing a systematic approach to data collection and analysis that can contribute to theory building with regard to strategy evolution.
Liminal ethnography: understanding segregated organisations
Authors: Bargiela‐Chiappini Francesca
Published: August 2007

Purpose

The paper aims to discuss liminal ethnography as a new approach for conducting research in segregated organisations.

Design/methodology/approach

The paper proposes liminality as a conceptual key to understanding both the condition of the organisational ethnographer and that of her interlocutors.Conversatiois the novel hermeneutical method that is discussed in conjunction with liminal ethnography.

Findings

Liminal ethnography as outlined in the paper emerged as an approach from preliminary contact with the organisational reality of the monastery as a type of total institution. Similarly,conversatiosuggested itself as a method that maximises limited face to face contact with interlocutors whose access to the external world is restricted by a behavioural code enshrined in a Rule.

Research limitations/implications

Paradoxically, the restrictions imposed on the researcher provided inspiration for the analytical approach proposed by the paper therefore initial limitations such as restricted access eventually spurred conceptual development.

Originality/value

The original approach should be of interest to organisational researchers operating in total institutions or in organisations where severely restricted access renders extant methodologies only partly applicable, if at all. The paper also discusses ethical issues arising from collaboration with rule‐governed communities.
Working with blinders on
Authors: Marri Anand R.
Published: August 2007

Purpose

The purpose of this paper is to present a critical race theory content analysis of research on technology and social studies education.

Design/methodology/approach

This study, using a critical race theory (CRT) framework, investigates how social studies education scholars have critically addressed the intersection between technology and race/ethnicity through a content analysis of articles in the journalsTheory and Research in Social Education(TRSE) andContemporary Issues in Technology and Teacher Education(CITE) since 1990.

Findings

This paper contends that the interaction between technology and race/ethnicity is rarely critically examined in these two prominent social studies education research journals.

Originality/value

In light of this neglect, the paper discusses the need for an in‐depth analysis of the reification of low‐level pedagogical methods with racial/ethnic minority students, an unexplored area of research.
Multicultural e‐learning project and comparison of teachers', student teachers' and pupils' perceptions about e‐learning
Authors: Orly Michael
Published: August 2007

Purpose

The purpose of this paper is to describe a special multicultural project in e‐learning that was accompanied by a research. In this project, student teachers experience the planning, implementation and receiving of feedback on computerized teaching of children from diverse multicultural groups. The aim of the research was to examine what e‐learning is according to teachers, pupils and student teachers from diverse cultural backgrounds.

Design/methodology/approach

The research population in the sample included 130 respondents in three groups: teachers', student teachers' and pupils'.

Findings

The uniqueness of this research is the comparison of the three groups and the results that show that in most areas that were checked, significant differences were found between the perception of the teachers, pupils and student teachers.

Practical implications

Teachers and student teachers should know what their pupils think of e‐learning and should consider it in order to improve their performance in e‐learning. The study's findings have significant implications for education systems and teachers in the design and implementation of online projects.

Originality/value

The value of the research findings is that they illuminate similar and differing viewpoints concerning e‐learning in culturally as well as functionally diverse populations. Teachers and pupils perceive e‐learning differently, and this has a direct influence on teaching and learning.
A conceptual model for the internet's impact on marketing in Iran
Authors: Ghazisaeedi Mehdi , Pitt Leyland F. , Kamal Chaharsooghi S.
Published: August 2007

Purpose

The potential impact of the internet on marketing is a common topic of discussion in marketing literature. However, there is still much debate on exactly what impact it will have on developing countries. To perceive this impact world‐wide, it is essential to spread some light to the less investigated parts of the globe as well. This study aims to reach a better conceptual model for the internet's impact on marketing in Iran, by examining Iranian marketing managers' perceptions of the internet's impact on their key marketing activities and comparing the results with other parts of the world.

Design/methodology/approach

The paper employs a cross‐sectional research design involving self‐administered delivery and collection surveys to Iranian marketing decision makers.

Findings

The findings suggest that the impact of these new media will be to cause firms to redefine markets, marketing activity and value creation, although these changes are not dramatic.

Research limitations/implications

The findings reported here are snapshots in time. The internet's rapid evolution and growth demand that regular tracking with longitudinal designs be implemented.

Practical implications

Firms need to make changes in the marketing activities and market definitions and to try to reach the new ways that are created through the internet.

Originality/value

A modified model for the world wide web marketing that seems to be more realistic for developing countries is presented.
The whole truth and nothing but the truth? The role of data quality today
Authors: Scarisbrick‐Hauser AnneMarie , Rouse Christina
Published: August 2007

Purpose

Historically, firms have done very well in collecting a large volume of data. Unfortunately, the data are often collected and stored without proper consideration being given to how they will be used later. This paper aims to consider how firms can more effectively gather usable data.

Design/methodology/approach

The methodology used was a conceptual approach using real‐time examples.

Findings

The findings indicate that organizations do not lack for data – they lack high quality, analyzable data.

Research limitations/implications

This paper does not provide an empirical sample. Future research should focus more specifically on the type of data firms collect and the reasons for collecting those data.

Practical implications

The paper shows the difference between simply collecting data and collecting data, which can be used at a later date.

Originality/value

The paper provides a blueprint for firms to enable more effective data collection and use.
External cost of air pollution from thermal power plants: case of Greece
Authors: Georgakellos Dimitrios A.
Published: August 2007

Purpose

The purpose of the paper is to quantify the external cost of airborne pollutants (i.e. sulphur and nitrogen oxides, carbon dioxide, and particulate matters) generated during electricity production in the thermal power plants in Greece.

Design/methodology/approach

This paper applies the EcoSenseLE online tool to examine the external cost of air pollution generated in all thermal power stations of 50 MW or higher capacity in Greece. The external cost has been calculated for five damage categories and by fuel types. Data for 2004 has been used and projections up to 2030 have been made.

Findings

This research finds that the external cost of the natural gas power plants is €13.87 per MWh which is the lowest for the system while the cost is estimated at €43.89 per MWh for lignite plants. The external cost of air pollution from the power sector in 2004 has been estimated at €1.89 billion and is expected to increase to €2.48 billion in 2025. The marginal external cost at the plant level varies from €8.76 to 93.15 per MWh. This variation is due to the quality of fuel, and the technology of plants.

Research limitations/implications

The general limitation of the external cost methodology applies to this work as it uses the standard method developed for the ExternE project. Similarly, the data limitations as well as assumptions related to the costs and exclusions/omissions of cost elements affect the results.

Practical implications

The estimation of external costs is important for decision makers in the electricity sector to develop strategies for emission reduction and to develop environmental and energy policies.

Originality/value

The contribution of the paper lies in its use of recent data for the estimation and projection of the external costs until 2030. This allows an understanding of the changes in the external costs from power generation in the country.
Simultaneous effect of ursolic acid and oleanolic acid on epidermal permeability barrier function and epidermal keratinocyte differentiation via peroxisome proliferator‐activated receptor‐α
Authors: LIM Suk Won , HONG Seung Phil , JEONG Sung Won , KIM Bora , BAK Hana , RYOO Hee Chang , LEE Seung Hun , AHN Sung Ku
Published: August 2007

Ursolic acid (UA) and oleanolic acid (ONA) are pentacyclic triterpenoids, which naturally occur in many medicinal herbs and plants. Recent research revealed that several pharmacological effects could be attributed to UA and ONA, such as anti‐tumor, anti‐inflammatory and anti‐microbial activities. To evaluate the effects of UA and ONA on epidermal permeability barrier recovery and normal skin, both flanks of hairless mice were topically treated with either 0.01~0.1 mg/mL UA or 0.1~1.0 mg/mL ONA after tape stripping and transepidermal water loss (TEWL) were assessed, and then hydration and TEWL were measured for 3 weeks with application of UA and ONA (2 mg/mL). We also investigated the morphological changes using light (LM) and electron microscopic (EM) examination. Finally, we observed that UA and ONA stimulated epidermal keratinocyte differentiation via peroxisome proliferator‐activated receptor (PPAR)‐α using Western immunoblotting. The recovery rate of epidermal permeability barrier after tape stripping increased in the UA‐ and ONA‐treated groups (0.1 mg/mL UA and 0.5 mg/mL ONA) at 6 h to more than 20% when compared to the vehicle‐treated group (P < 0.05). In both groups, hydration was increased compared to the vehicle group from 1 week without TEWL alteration (P < 0.05). An LM finding showed that epidermal thickening was frequently observed (UA > ONA > vehicle). EM examination revealed an increase in secretion and in the number of lamellar bodies in treated groups and that complete formation of lipid bilayers was also prominent (ONA > UA > vehicle). Protein expression of PPAR‐α, involucrin, loricrin and filaggrin increased twofold and threefold in HaCaT cells treated for 24 h with either ONA (10 µmol/L) or UA (10 µmol/L), respectively, reflecting that the UA and ONA can improve the recovery of skin barrier function and induce epidermal keratinocyte differentiation via PPAR‐α. Taken together, these results suggest that UA and ONA will be pertinent candidates for the improvement of epidermal permeability barrier function.
Toll‐like receptor 2 –196 to 174del polymorphism influences the susceptibility of Japanese people to gastric cancer
Authors: Tahara Tomomitsu , Arisawa Tomiyasu , Wang Fangyu , Shibata Tomoyuki , Nakamura Masakatsu , Sakata Mikijyu , Hirata Ichiro , Nakano Hiroshi
Published: August 2007

Toll like receptors (TLR) play important roles in the signaling of many pathogen‐related molecules and endogenous proteins associated with immune activation. The –196 to –174del polymorphism affects the TLR2 gene and alters its promoter activity. We investigated the influence of the TLR2–196 to –174del polymorphism on the occurrence of non‐cardiac gastric cancer (NCGC) in a Japanese population. The study was carried out with 289 patients with NCGC, 309 non‐cancer patients with abdominal discomfort and 146 healthy controls. The –196 to –174del TLR2 polymorphism was investigated using the allele‐specific polymerase chain reaction method in all of the subjects. The –196 to –174del/del genotype of TLR2 showed a significantly higher frequency in NCGC patients than in healthy controls (adjusted odds ratio [OR] = 6.06; 95% confidence interval [CI] = 1.86–19.72). Similarly, the frequency of the –196 to –174del/del genotype was significantly higher among NCGC patients than in non‐cancer patients (adjusted OR = 2.02; 95% CI = 1.22–3.34). The same genotype was associated with an increased risk of both intestinal (OR = 2.00, 95% CI = 1.12–3.60) and diffuse‐type (OR = 2.05; 95% CI = 1.11–3.79) histopathology. There were no significant associations between TLR2 genotypes and tumor stage and anatomical location. Our data suggest that the –196 to –174del/del genotype of TLR2 may increase the risk of gastric cancer in the Japanese population. (Cancer Sci 2007; 98: 1790–1794)
Respiratory hospital admissions were associated with ambient airborne pollen in Darwin, Australia, 2004–2005
Authors: Hanigan I. C. , Johnston F. H.
Published: August 2007

Background
Although the role of pollen and fungus in specific allergic disorders has been well established, the public health impacts of ambient concentrations of airborne pollen and fungal spores; the shapes of concentration–response relationships; and the relative effects of different taxa are gaps in current knowledge.

Objective
To investigate associations between daily average ambient pollen and fungal spore concentrations with hospital admissions for total respiratory diseases; asthma; chronic obstructive pulmonary disease (COPD); and respiratory infections in Darwin, Australia, during the period from April 2004 to November 2005.

Methods
We assessed these relationships in a two‐stage modelling approach designed to quantify potential non‐linear relationships. First, generalized additive models determined the shapes of concentration–response relationships. Second, linear associations were examined using generalized linear models. Non‐linear relationships were analysed by categorizing pollen and fungal spore concentrations based on their distributions.

Results
Positive linear associations were found between total pollen concentrations and hospital admissions for total respiratory diseases and COPD. While our exploratory first‐stage analysis suggested non‐linear relationships for total pollen with asthma and respiratory infections, no convincing evidence for these relationships was found in the second‐stage analysis. When individual taxa were investigated, associations were the strongest in relation to Myrtaceae pollen (the dominant tree taxa in the region), while positive associations not attaining statistical significance were observed for Poaceae, Cyperaceae and Arecaceae. No associations were evident for any conditions with fungal spores.

Conclusions
Our finding of an association between pollen count and respiratory hospital admissions that could not be explained by asthma admissions suggests that ambient airborne pollens might have a wider public health impact than previously recognized.
Is the effect of the NAO on North‐east Arctic cod, Gadus morhua, recruitment stock‐dependent?
Authors: SOLOW ANDREW R. , BEET ANDREW R.
Published: August 2007

There is considerable interest in understanding the effect of the North Atlantic Oscillation (NAO) on recruitment to North Atlantic cod stocks. An earlier analysis of data for the North‐east Arctic cod stock showed that, while there is an empirical relationship between recruitment and the NAO over the period 1973–96, this relationship was absent over the period 1946–72. It has recently been suggested that the effect of the NAO on recruitment depends on the size of the spawning stock. Here, the possibility that this explains the earlier result for North‐east Arctic cod is tested and rejected.
The marine temperature and depth preferences of Arctic charr (Salvelinus alpinus) and sea trout (Salmo trutta), as recorded by data storage tags
Authors: RIKARDSEN AUDUN H. , DISERUD OLA H. , ELLIOTT J. MALCOLM , DEMPSON J. BRIAN , STURLAUGSSON JOHANNES , JENSEN ARNE J.
Published: August 2007

Eleven Arctic charr (Salvelinus alpinus) (370–512 mm) and eight sea trout (Salmo trutta) (370–585 mm in length) were tagged externally or internally with depth‐ and temperature‐measuring data‐storage tags (DST) before they were released into the sea in the Alta Fjord in north Norway in June 2002. All sea trout were recaptured after they spent 1–40 days at sea, while all Arctic charr were recaptured after 0.5–33 days at sea. On average, trout preferred water about 0.6 m deeper and 1.3°C warmer than Arctic charr. Arctic charr spent >50% of their time between 0 and 1 m depth, while trout spent >50% of their time between 1 and 2 m depth. Both species spent >90% of their time in water no deeper than 3 m from the water surface. However, sea trout dove more frequently and to greater depths (max. 28 m) than Arctic charr (max. 16 m), and these deep dives were most frequently performed at the end of the sea migration. Arctic charr demonstrated a diel diving pattern, staying on average about 0.5 m deeper between 08:00 hours and about 15:00 hours than during the rest of the 24 h, even though there was continuous daylight during the experiments. When comparing data obtained from the DSTs with temperature measurements within the fjord system, the two species were observed to select different feeding areas during their sea migration, the sea trout choosing the inner and warmer parts of the fjord, in contrast to the Arctic charr that preferred the outer, colder parts of the fjord. The observed differences in migration behaviour between the two species are discussed in relation to species preferences for prey and habitat selection, and their optimal temperatures for growth.
Striped marlin (Tetrapturus audax) movements and habitat utilization during a summer and autumn in the Southwest Pacific Ocean
Authors: SIPPEL TIM J. , DAVIE PETER S. , HOLDSWORTH JOHN C. , BLOCK BARBARA A.
Published: August 2007

Six striped marlin (Tetrapturus audax) were caught on hook and line from recreational fishing boats near northern New Zealand (34°S, 174°E) and tagged and released with pop‐off satellite archival tags. For periods ranging from 22 to 60 days over the geographical range 168°E–170°W and 13–34°S, five tags collected a total of 202 days (range of 21–60 days) of data. These data permit the investigation of striped marlin geographical and vertical movements and water temperatures occupied from February to June 2003. One hundred and one days of geoposition data showed a preliminary view of their movements in and around New Zealand waters. Transmitted temperature and depth data indicated striped marlin spent 80% (±2%) of their time in the mixed layer including 72% (±2%) of their time in the top 5 m. Temperature data indicated 75% (±10%) of the striped marlin’s time was spent in water temperatures between 20.1 and 24.0°C. Tagged striped marlin moved faster during periods of directed movement away from New Zealand versus periods of passive movements when the fish were proximal to New Zealand or not moving in any specific direction. These data support some existing hypotheses about striped marlin physiological ecology and allow preliminary suggestions about how striped marlin bycatch might be reduced.
Optimized biophysical model for Icelandic cod (Gadus morhua) larvae
Authors: BRICKMAN DAVID , TAYLOR LORNA , GUDMUNDSDÓTTIR ÁSTA , MARTEINSDÓTTIR GUDRUN
Published: August 2007

A characteristic of biophysical models (BPM) is that they contain a number of parameters that are poorly known or only known within a range of possible values. This paper describes an efficient optimized BPM developed to simulate the Icelandic cod pelagic 0‐group survey data. The method is based on presenting the results as a probability density function (PDF) that a particle released from a given spawning drifts downstream to a given grid location some time later. The model determines egg production model parameters (peak spawning time, spawning duration, number of eggs released) for each of 15 spawning grounds as the solution of a bound constrained optimization problem that minimizes model‐data misfits in abundance and age distributions. The model is applied to simulating the 2002 and 2003 summer survey data. The model does a reasonable job of simulating the observed inshore / offshore abundance gradient and spatial age gradient for each year. Problem areas are explained from the point of view of model limitations. We caution that the results from an optimized model should always be assessed with the model’s limitations in mind and with respect to whatever biological data are available.
Tissue nutrient concentrations in freshwater aquatic macrophytes: high inter‐taxon differences and low phenotypic response to nutrient supply
Authors: DEMARS BENOÎT O. L. , EDWARDS A. C.
Published: August 2007

1. The elemental composition and stoichiometry of aquatic plants has often been suggested to reflect the nutrient enrichment of aquatic habitats. However, the relationship is often weak. Moreover, uncertainties remain in the relevance of laboratory derived critical plant tissue nutrient concentrations to maximum yield or growth rates in the field.

2. Aquatic vascular plants and bryophytes, overlying water and sediment samples were collected to test whether freshwater aquatic macrophytes: (i) show tissue nutrient deficiencies when growing in oligotrophic freshwater habitats, and (ii) have strict homeostatic stoichiometry.

3. Plant nutrient concentrations were significantly related to total inorganic nitrogen (or nitrate), total dissolved phosphorus and sediment total phosphorus. However, these relationships were weak. Virtually all the variance in plant tissue nutrient concentrations, however, could be explained by species (taxon) identity.

4. Critical tissue nutrient concentrations for 95% maximum yield or 95% maximum growth rate in aquatic angiosperms, determined from laboratory bioassays, suggested that nutrients should not limit yield in wild aquatic macrophytes. However, there were a substantial number of samples where potential growth rate limitation was possible, particularly due to phosphorus.

5. Strict C : N : P stoichiometric ratios were found for both vascular plants and bryophytes, suggesting little scope for plants as indicators of nutrient enrichment, but provide robust stoichiometric data for studies on ecosystem metabolism and nutrient cycling.
Ecosystem input of nitrogen through biological fixation in feather mosses during ecosystem retrogression
Authors: LAGERSTRÖM A. , NILSSON M.‐C. , ZACKRISSON O. , WARDLE D. A.
Published: August 2007

Ecosystem retrogression occurs during the very long‐term absence of major disturbances, and it is characterized by decreases in productivity, decomposition rates and nutrient availability. Ratios of total soil nitrogen (N) to phosphorus (P) also characteristically increase during retrogression, but the nature of N inputs to ecosystems undergoing retrogression has seldom been explored.

We studied a 5000‐year‐old chronosequence involving 30 islands that differed greatly in history of disturbance (wildfire through lightning strike), with increasing time since disturbance leading to ecosystem retrogression. For each island, we quantified N inputs through biological fixation by cyanobacteria hosted by each of two feather moss species that dominate the ground layer vegetation (Pleurozium schreberi and Hylocomium splendens), and compared these with N inputs through atmospheric deposition.

Both N2 fixation per unit land area and fixation per unit moss mass increased significantly with increasing time since disturbance for both moss species. As retrogression progressed, the amount of total N input through biological fixation increased to levels comparable to that of input through atmospheric deposition.

Across the chronosequence, N has been accumulating in the humus layer at a rate of 1·8 kg ha−1 year−1 in the absence of fire during the past 5000 years. The added N input from biological fixation in this area of low atmospheric N deposition helps explain this relatively high rate of sequestration.

Our results show that, contrary to several claims in the literature, biological N2 fixation is not only important in early‐successional ecosystems but also in late‐successional systems that have undergone retrogression. This fixation can contribute both to the elevated N : P ratios that occur during retrogression and to accumulation of N capital in the soil. However, much of this N may exist in forms that are relatively unavailable to co‐existing plant species.
What is the required minimum landscape size for dispersal studies?
Authors: FRANZÉN MARKUS , NILSSON SVEN G.
Published: August 2007

Among small animals dispersal parameters are mainly obtained by traditional methods using population studies of marked individuals. Dispersal studies may underestimate the rate and distance of dispersal, and be biased because of aggregated habitat patches and a small study area. The probability of observing long distance dispersal events decreases with distance travelled by the organisms. In this study a new approach is presented to solve this methodological problem.

An extensive mark–release–recapture programme was performed in an area of 81 km2in southern Sweden. To estimate the required size of the study area for adequate dispersal measures we examined the effect of study area size on dispersal distance using empirical data and a repeated subsampling procedure. In 2003 and 2004, two species of diurnal burnet moths (Zygaenidae) were studied to explore dispersal patterns.

The longest confirmed dispersal distance was 5600 m and in total 100 dispersal events were found between habitat patches for the two species. The estimated dispersal distance was strongly affected by the size of the study area and the number of marked individuals. For areas less than 10 km2most of the dispersal events were undetected. Realistic estimates of dispersal distance require a study area of at least 50 km2.

To obtain adequate measures of dispersal, the marked population should be large, preferably over 500 recaptured individuals. This result was evident for the mean moved distance, mean dispersal distance and maximum dispersal distance.

In general, traditional dispersal studies are performed in small study areas and based on few individuals and should therefore be interpreted with care. Adequate dispersal measures for insects obtained by radio‐tracking and genetic estimates (gene flow) is still a challenge for the future.
Head posture and dental wear evaluation of bruxist children with primary teeth
Authors: VÉLEZ A. L. , RESTREPO C. C. , PELÁEZ‐VARGAS A. , GALLEGO G. J. , ALVAREZ E. , TAMAYO V. , TAMAYO M.
Published: August 2007

Summary  The aim of the present study was to compare the head position and dental wear of bruxist and non‐bruxist children with primary dentition.

Methods:  All the subjects had complete primary dentition, dental and skeletal class I occlusion and were classified as bruxist or non‐bruxist according to their anxiety level, bruxism described by their parents and signs of temporomandibular disorders. The dental wear was drawn in dental casts and processed in digital format. Physiotherapeutic evaluation and a cephalometric radiograph with natural head position were also performed for each child to evaluate the cranio‐cervical position for the bruxist group (n = 33) and the control group (n = 20). The variables of the two groups were compared, using the Student t‐test and Mann–Whitney U‐test.

Results:  A more anterior and downward head tilt was found in the bruxist group, with statistically significant differences compared with the controls. More significant dental wear was observed in the bruxist children.

Conclusions:  Bruxism seems to be related to altered natural head posture and more intense dental wear. Further studies are necessary to explore bruxism mechanisms.
Influence of altered occlusal guidance on masticatory muscle activity during clenching
Authors: OKANO N. , BABA K. , IGARASHI Y.
Published: August 2007

Summary  This study investigated the influence of experimentally altered occlusal guidance on masticatory muscle activity. Twenty healthy human subjects (15 males and five females with an average age of 26·5 years) volunteered to participate in this study. Metallic occlusal overlays were fabricated for the lower working side canine and overlaid on the second molar and the non‐working side second molar to simulate a canine‐protected occlusion, group function occlusion and bilateral balanced occlusion. Electromyography (EMG) activities in the bilateral masseter, anterior and posterior temporalis were recorded during maximal clenching. The experimental occlusal pattern revealed to have statistically significant effects on EMG activity. As the most characteristic change, EMG activity in the anterior temporalis significantly increased in the simulated group function occlusion and the simulated bilateral balanced occlusion compared with the simulated cuspid protected occlusion. The increased teeth contacts to the posterior region altered the unilateral pattern of the anterior temporalis activity to the bilateral pattern, while that of masseter activity remained unchanged.
Relation between cervical posture on lateral skull radiographs and electromyographic activity of masticatory muscles in caucasian adult women: a cross‐sectional study
Authors: TECCO S. , TETE S. , FESTA F.
Published: August 2007

Summary  The aim of this study was to evaluate the association between cervical posture on lateral skull radiographs and surface electromyographic recordings (sEMG) of head and neck muscles. The sample comprised 40 Caucasian adult females, average age 26·8 (20–48); lateral skull radiographs were obtained in natural head position (mirror position). sEMG activity was bilaterally investigated for the following muscles: masseter, anterior temporalis, digastric, posterior cervical, sternocleidomastoid and upper and lower trapezius. All muscles were monitored at rest and during maximal voluntary clenching (MVC). A Pearson’s correlation coefficient revealed significant correlations (P < 0·01) between cranio‐cervical angulations and sEMG activity of masseter, digastric, lower trapezius, during MVC and anterior temporalis at rest. Significant correlations (P < 0·01) were also found between cervical lordosis angle and sEMG activity of masseter (during MVC) and lower trapezius (at rest). In view of transversal method, no conclusion was possible about the mechanism concerning these results. Future longitudinal studies should be directed to understand the extent of environmental and genotype influences by masticatory muscle activity on cervical posture.
Improving actigraphic sleep estimates in insomnia and dementia: how many nights?
Authors: VAN SOMEREN EUS J. W.
Published: August 2007

In order to investigate how the duration of actigraphic recordings affects the reliability of actigraphic estimates of sleep and 24‐h activity rhythm variables, two to 3 weeks of actigraphy were recorded, from which pairs of variables derived from two periods of increasing length (1–10 days) were compared. Two groups were studied: (1) 10 subjects suffering from primary insomnia; and (2) 12 demented elderly subjects living semi‐independently in group care facilities of homes for the elderly. Actigraphic estimates of primary measures of sleep (duration and efficiency) and of the 24‐h activity pattern (interdaily stability, intradaily variability and amplitude) were calculated on variable lengths of the actigraphic recordings. The average absolute difference of two estimates decreased – and reliability increased – strongly with an increasing number of days analysed. An acceptable reliability of the interdaily stability estimate required more than 7 days of recording. It can be concluded that a valuable improvement in the reliability of actigraphic sleep estimates can be obtained by simply increasing the number of recording nights. The results support the importance of day‐to‐day variability in insomnia and dementia that has already been previously noted by others, and even suggest the presence of ’week‐to‐week’ variability. This variability may have been involved in the equivocal results of treatment studies in insomnia and dementia where outcome measures were based on a limited number of nights. Such studies could profit from extension of the recording duration to, e.g. 2 weeks, and from the inclusion of variability measures as measures of clinical interest.
Posturographic sleepiness monitoring
Authors: FORSMAN PIA , WALLIN ANDERS , TIETÄVÄINEN AINO , HÆGGSTRÖM EDWARD
Published: August 2007

Although reduced sleep often underlies traffic and occupational accidents, convenient sleepiness testing is lacking. We show that posturographic balance testing addresses this issue, because balance testing predicts hours of wakefulness, which could facilitate sleepiness testing. Here, we equate balance scores from separate trials, blinded to the experimenter, with those recorded as a function of known and increasing time awake (i.e. during sustained wakefulness); we show, that the time awake in separate trials is posturographically measurable: positive predictive value 69%, sensitivity 56%, and specificity 96%. These results encourage further work developing posturographic sleepiness monitoring.
Prevalence of papilloedema in patients with sleep apnoea syndrome: a prospective study
Authors: PETER LAURE , JACOB MAUD , KROLAK‐SALMON PIERRE , PETITJEAN THIERRY , BASTUJI HÉLÈNE , GRANGE JEAN‐DANIEL , VIGHETTO ALLAIN
Published: August 2007

The association of papilloedema (PO) with respiratory diseases and especially obstructive sleep apnoea (OSA) syndrome has been emphasised in many reports. The pathophysiology could rely on the episodic increase of intracranial pressure related to apnoeic episodes during night sleep. Nevertheless, prevalence of papilloedema in patient with OSA syndrome remains unknown. As this information could improve diagnosis and therapeutic strategies, the aim of the present study was to investigate the prevalence of PO in an OSA syndrome population. From 95 successive, recently diagnosed OSA patients, 35 answered a questionnaire about visual symptoms and underwent fundoscopic examination. Visual symptoms suggestive of PO were present in 40% of the patients, but none had PO. As a conclusion, PO does not seem to be frequently associated with OSA syndrome and systematic screening of PO in these patients does not seem to be warranted. Nevertheless, patients with visual complaints evocative of papilloedema should have their eye fundus checked since the association between OSA and PO exists. Further studies, including more patients, might be useful to establish which patients are at particular risk for this complication.
Periodic leg movements during sleep and wakefulness in narcolepsy
Authors: DAUVILLIERS YVES , PENNESTRI MARIE‐HÉLÈNE , PETIT DOMINIQUE , DANG‐VU THANH , LAVIGNE GILLES , MONTPLAISIR JACQUES
Published: August 2007

The objectives of the study were to measure the prevalence of periodic leg movements during NREM and REM sleep (PLMS) and while awake (PLMW) and to assess the impact of PLMS on nocturnal sleep and daytime functioning in patients with narcolepsy. One hundred and sixty‐nine patients with narcolepsy and 116 normal controls matched for age and gender were included. Narcoleptics with high and low PLMS indices were compared to assess the impact of PLMS on sleep and Multiple Sleep Latency Test (MSLT) variables. More narcoleptics than controls had a PLMS index greater than 5 per hour of sleep (67% versus 37%) and an index greater than 10 (53% versus 21%). PLMS indices were higher both in NREM and REM sleep in narcoleptic patients, but the between‐group difference was greater for REM sleep. A significant increase of PLMS index was also found with aging in both narcoleptic patients and controls. PLMW indices were also significantly higher in narcoleptic patients. Patients with an elevated index of PLMS had a higher percentage of stage 1 sleep, a lower percentage of REM sleep, a lower REM efficiency and a shorter MSLT latency. The present study demonstrates a high frequency of PLMS and PLMW in narcolepsy, an association between the presence of PLMS and measures of REM sleep and daytime functioning disruption. These results suggest that PLMS represent an intrinsic feature of narcolepsy.