bluuebunny/crossref_metadata_2025 huggingface dataset:
Free‐Form estimation of soil hydraulic properties using Wind’s method
Authors: Iden S. C. , Durner W.
Published: November 2008

Transient evaporation experiments offer the potential to determine simultaneously the soil hydraulic properties necessary to simulate water flow in unsaturated soils. We present a new algorithm for determining the retention and conductivity curve from evaporation experiments which uses Wind’s method with a free‐form soil water retention function. Our algorithm estimates nodal values of volumetric water content and derives a smooth and monotone retention curve by cubic Hermite interpolation. A multilevel routine increases the number of nodes and their adequate number is identified by a performance criterion which balances goodness of fit, the cross correlation between the estimated water contents and the number of degrees of freedom. We calculate point values of unsaturated hydraulic conductivity by the instantaneous profile method and discard unreliable conductivity estimates by a statistical filter criterion. Results for three synthetic data sets including an uncertainty analysis of the estimated retention curves show that the algorithm is suitable to identify, both correctly and precisely, the soil hydraulic properties. An application to a real data set confirms these results. In order to enable the free‐form functions to be used in numerical flow simulations, we extrapolate the retention function to the dry range and compute a coupled conductivity function based on the Mualem model. Major advantages of the proposed method are the enormous flexibility provided by the free‐form functions, the low level of parameter cross‐correlation in comparison with classic parametric functions, and the possibility of assessing the uncertainty of the retention curve individually in different ranges of pressure head.
The PESERA coarse scale erosion model for Europe. I. – Model rationale and implementation
Authors: Kirkby M. J. , Irvine B. J. , Jones R. J. A. , Govers G. ,   PESERA team
Published: November 2008

The principles and theoretical background are presented for a new process‐based model (PESERA) that is designed to estimate long‐term average erosion rates at 1 km resolution and has, to date, been applied to most of Europe. The model is built around a partition of precipitation into components for overland flow (infiltration excess, saturation excess and snowmelt), evapo‐transpiration and changes in soil moisture storage. Transpiration is used to drive a generic plant growth model for biomass, constrained as necessary by land use decisions, primarily on a monthly time step. Leaf fall, with corrections for cropping, grazing, etc., also drives a simple model for soil organic matter. The runoff threshold for infiltration excess overland flow depends dynamically on vegetation cover, organic matter and soil properties, varying over the year. The distribution of daily rainfall totals has been fitted to a Gamma distribution for each month, and drives overland flow and sediment transport (proportional to the sum of overland flow squared) by summing over this distribution. Total erosion is driven by erodibility, derived from soil properties, squared overland flow discharge and gradient; it is assessed at the slope base to estimate total loss from the land, and delivered to stream channels.
Modified technique to assess the wettability of soil aggregates: comparison with contact angles measured on crushed aggregates and bulk soil
Authors: Goebel M.‐O. , Bachmann J. , Woche S. K.
Published: November 2008

Wettability parameters determined for individual soils often show a considerable variation depending on the kind of sample (aggregated or homogeneous material) and the method used. To investigate the causes of this variation, we assessed wettability of both intact and crushed aggregates and bulk soil using different methods. Wettability of intact aggregates was characterized by a modified technique where the specific infiltration rates of water and a completely wetting liquid were used to define a repellency index. Contact angles were determined on crushed aggregates and bulk soil using the Wilhelmy plate and capillary rise methods. The repellency index was found to be sensitive to slight differences in wettability and was in good agreement with Wilhelmy plate contact angles. Contact angles measured with the capillary rise method showed a strong deviation from those determined with the Wilhelmy plate method. This can be ascribed to the underlying assumptions of the capillary rise method (i.e. cylindrical and parallel capillaries) resulting in an over‐estimation of contact angle, particularly for the small‐sized particle fraction because of the impact of inertia and pore structure. No significant differences were found between intact and crushed aggregates whereas the bulk soil was slightly more water‐repellent, probably because of a somewhat larger organic carbon content. We conclude that the contact angle determined by the Wilhelmy plate method and the repellency index are appropriate parameters for characterizing soil water repellency because they detected small changes in wettability over a wide range extending from subcritical water repellency to hydrophobicity.
Effect of organic amendment on amount and chemical characteristics of humic acids in upland field soils
Authors: Kawasaki S. , Maie N. , Kitamura S. , Watanabe A.
Published: November 2008

To assess the effect of continuous organic material (OM) application on soil humic acids, the amount and chemical characteristics of humic acids in various types of soils (n = 10) were compared between plots treated with farmyard manure (FYM) or rice straw compost (RSC) plus chemical fertilizer (CF) and plots treated with CF alone. The degree of humification (degree of darkening), molecular size distribution and 13C cross polarization/magic angle spinning nuclear magnetic resonance spectra of humic acids from CF‐treated soils showed wide variation among the soils. Humic acid content was generally larger in OM + CF soils than in corresponding CF soils, and the stable C isotopic ratio suggested partial replacement of indigenous humic acids with OM‐derived ones even where no apparent increase in humic acid content was observed. The rate of OM application and the indigenous humic acid content were related positively and negatively, respectively, to the apparent accumulation rate of humic acids among soils. The degree of humification of humic acids was generally smaller in OM + CF soils than in CF soils. Humic acids extracted from FYM and RSC exhibited chemical characteristics typical of humic acids having a smaller degree of humification, which suggested the contribution of OM‐derived humic acids to the differences between OM + CF and CF soil humic acids, such as larger average molecular sizes and smaller and larger proportions of aromatic C and O‐alkyl C, respectively, relative to total C in the OM + CF soil humic acids. Little change was observed in the chemical characteristics of humic acids when the degree of humification of indigenous humic acids was small. The effect of OM application on the chemical characteristics of humic acids was most conspicuous in soils containing humic acids having an intermediate degree of humification, possibly resulting from the combination of accelerated degradation of indigenous humic acids and the accumulation of OM‐derived humic acids.
The UV‐absorbance of dissolved organic matter predicts the fivefold variation in its affinity for mobilizing Cu in an agricultural soil horizon
Authors: Amery F. , Degryse F. , Cheyns K. , De Troyer I. , Mertens J. , Merckx R. , Smolders E.
Published: November 2008

It is well established that dissolved organic matter (DOM) mobilizes copper (Cu) in soils but it is unknown to what extent variable DOM quality affects this. During a 5 month period, 250 leachates of an uncontaminated agricultural soil were sampled at 45 cm depth using passive capillary wick samplers. The dissolved Cu and organic carbon (DOC) concentrations varied sevenfold and were weakly correlated (r = 0.56). The [Cu] : [DOC] ratio varied fivefold and exhibited a significant positive correlation (r = 0.77) with the specific UV‐absorbance of DOM at 254 nm (SUVA), indicating that the more aromatic DOM had higher Cu affinity. The dissolved Cu concentrations were predicted by an assemblage model in WHAM6 using the composition of the solid phase above the wick samplers and that of the solution, including DOC. The predicted [Cu] : [DOC] ratio was almost constant when assuming default DOM properties with 65% of all DOM active as fulvic acid (%AFA). The %AFA was subsequently varied proportionally to the SUVA of DOM and using the SUVA of pure FA (SUVAFA) as a fitting parameter. In that case, the variation in the predicted [Cu] : [DOC] ratio was much larger and the predicted Cu concentrations were within a factor of 1.4 of the measured values for 90% of the samples. The fitted SUVAFA was 38 l g−1 cm−1, in excellent agreement with that of Suwannee River FA (SUVAFA = 37 l g−1 cm−1). It is concluded that the DOM quality, e.g. the aromaticity, should be taken into account when estimating Cu mobility in soils.
Long‐term carbon loss and CO2‐C release of drained peatland soils in northeast Germany
Authors: Kluge B. , Wessolek G. , Facklam M. , Lorenz M. , Schwärzel K.
Published: November 2008

Peatlands are common in many parts of the world. Draining and other changes in the use of peatlands increase atmospheric CO2 concentration. If we are to make reliable quantitative predictions of that effect, we need good information on the CO2 emission rates from peatlands. The present study uses two different methods for predicting CO2‐C release of peatland soils: (i) a 40‐year field investigation of balancing organic carbon stocks and (ii) short‐term CO2‐C release rates from laboratory experiments. To estimate long‐term losses of peat, and its resulting C input to the atmosphere, we combined highly detailed maps of surface topography and its changes, and the organic C contents and bulk densities of a drained peatland from different years. Short‐term CO2‐C release rates were measured in the laboratory by incubating soil samples from several soil horizons at various temperatures and soil moistures. We then derived nonlinear CO2‐C production functions, which we incorporated into a numerical simulation model (HYDRUS). Using HYDRUS, we calculated daily soil water components and CO2‐release for (i) real‐climate data from 1950 to 2003 and (ii) a climate scenario extending to 2050, including an increase in temperature of 2°C and 20% less rainfall during the summer half year, i.e. from April to September inclusive. From our field measurements, we found a mean annual decrease of 0.7 cm in the thickness of the peat. Large losses (> 1.5 cm year−1) occurred only during periods when groundwater levels were low (i.e. a deep water‐table). The annual CO2‐C release results in a mean loss from the peat of about 700 g CO2‐C m−2, mostly as a direct contribution to the atmosphere. Both methods produced very similar results. The model scenarios demonstrated that CO2‐C loss is mainly controlled by the groundwater (i.e. water‐table) depth, which controls subsurface aeration. A local climate scenario estimated a c. 5% increase of CO2‐C losses within the next 50 years.
Fine‐scale genetic structure of Atlantic salmon (Salmo salar) using microsatellite markers: effects of restocking and natural recolonization
Authors: GRANDJEAN FRÉDÉRIC , VERNE SEBASTIEN , CHERBONNEL CORINNE , RICHARD ARNAUD
Published: November 2008

1. An important goal of conservation biology is to preserve the evolutionary potential of a species by maintaining natural levels of genetic diversity. Here, we assess the population differentiation in the Atlantic salmon, Salmo salar, listed in Annex II of the European Habitats Directive, to provide valuable information for its conservation in Normandy (France).

2. Samples collected from 10 natural sites revealed that 13 of 14 microsatellite loci were polymorphic. Significant differentiation among populations was detected (FST = 0.054, P < 0.001), and all FST pairwise comparisons except one were significant. A genetic split was observed between populations inhabiting streams with limestone geology compared to those inhabiting streams with siliceous geology, which could reflect adaptative differences.

3. Hatchery stocks used for the restocking of two rivers were genetically distinct from native stocks.

4. Analysis of three stream habitats restored in 1995 showed that all were recolonized naturally by wild salmon from geographically close populations and no founder effects were detected. Allelic richness was similar between recolonized and wild populations.

5. From a management perspective, our study revealed that restoration of habitat is very effective to recreate new populations in rivers from which salmon have disappeared and that natural recolonization can be fast and effective in terms of genetic diversity.
Trophic relationships in a tropical stream food web assessed by stable isotope analysis
Authors: COAT SOPHIE , MONTI DOMINIQUE , BOUCHON CLAUDE , LEPOINT GILLES
Published: November 2008

1. Stable isotope analysis, coupled with dietary data from the literature, was used to investigate trophic patterns of freshwater fauna in a tropical stream food web (Guadeloupe, French West Indies).

2. Primary producers (biofilm, algae and plant detritus of terrestrial origin) showed distinct δ13C signatures, which allowed for a powerful discrimination of carbon sources. Both autochthonous (13C‐enriched signatures) and allochthonous (13C‐depleted signatures) resources enter the food web. The migrating behaviour of fishes and shrimps between marine and freshwater during their life cycles can be followed by carbon isotopes. Here, shrimp δ13C signatures were shown to shift from −16‰ (for juveniles under marine influence) to −24.7‰ (for adults in freshwater habitats). For resident species, δ13C values partly reflected the species’ habitat preferences along the river continuum: species living in river mouths were 13C‐enriched in comparison with those collected upstream.

3. Nitrogen isotopic ratios were also discriminating and defined three main trophic guilds among consumers. The δ15N values of herbivores/detritivores were 5.0–8.4‰, omnivores 8.8–10.2‰ and carnivores 11–12.7‰.

4. Mixing model equations were employed to calculate the possible range of contribution made by respective food sources to the diet of each species. The results revealed the importance of omnivorous species and the dependence of riverine biota on terrestrial subsidies, such as leaf detritus and fruits. Finally, the abundance of shrimps and their feeding habits placed in relief their key role in tropical freshwater food webs. Isotopic analysis provides a useful tool for assessing animal feeding patterns.
Macrophytes as refuge or risky area for zooplankton: a balance set by littoral predacious macroinvertebrates
Authors: SAGRARIO GONZÁLEZ , De LosÁNGELES MARÍA , BALSEIRO ESTEBAN , ITUARTE ROMINA , SPIVAK EDUARDO
Published: November 2008

1. Zooplankton use macrophytes as day‐time refuge areas when trying to escape from pelagic predators. But macrophytes can also host a diverse and abundant macroinvertebrate assemblage and zooplankton are also likely to face predacious macroinvertebrates once they enter the littoral zone. This study aimed to elucidate the role of macroinvertebrates in determining the refuge capacity of macrophytes.

2. We conducted a field enclosure experiment using plastic bags and complementary laboratory feeding trials to test how macroinvertebrates counteract the benefits to zooplankton of the macrophyte refuge. The field experiment consisted of three treatments with different macroinvertebrate assemblages: without predators (WP), low abundance and diversity (LAD) and high abundance and diversity of predators (HAD – which represents lake conditions).

3. Populations of Diaphanosoma brachyurum, Bosmina huaronensis and Moina micrura (Cladocera) and of both male and female Notodiaptomus incompositus (Copepoda, Calanoida) declined (by nearly 80%) in the presence of HAD in comparison to WP and LAD treatments.

4. Feeding trials revealed that Buenoa sp. (backswimmer), adults of Palaemonetes argentinus (grass shrimp) and Cyanallagma interruptum (damselfly) had a significant negative impact on cladocerans (D. brachyurum, B. huaronensis) and the calanoid copepod population (males, females and copepodites). These predators showed a strong predation effect ranging from 75% to 100% reductions of zooplankton populations.

5. The refuge effect offered by macrophytes to zooplankton depends on and is balanced by the predacious macroinvertebrate assemblage that plants host. The risk of confronting littoral predators is high and macroinvertebrate presence can turn the macrophytes into risky areas for zooplankton.
Low impact of climate change on subalpine grasslands in the Swiss Northern Alps
Authors: VITTOZ PASCAL , RANDIN CHRISTOPHE , DUTOIT ANNELISE , BONNET FRANÇOIS , HEGG OTTO
Published: November 2008

While phenological shifts and migration of isolated species under climate change have already been observed on alpine summits, very few studies have focused on community composition changes in subalpine grasslands. Here we use permanent plots monitored since 1954 and precisely located phytosociological censuses from 1970 to study compositional changes of subalpine grasslands in two distinct regions of the Swiss Northern Alps. In both areas, warming trends during the monitoring period were associated with changes in land management (abandonment of goat and sheep pasturing or grazing replaced by mowing). Old and recent inventories were compared with correspondence analyses (CA). Ecological indicator values, community‐affinities and biological traits of the species were used to infer the factors responsible for triggering the observed changes. In both regions, subalpine grasslands were stable with smaller changes than have previously been observed in alpine environments. Only a few species appeared or disappeared and changes were generally limited to increasing or decreasing frequency and cover of certain taxa. At one site, grazing abandonment favored fallow species. Some of these species were located at their upper altitudinal distribution limits and may have spread because of rising temperatures. In both areas, declining species were predominantly alpine and low‐growing species; their decline was probably due to increased competition (e.g., shadow) with more vigorous subalpine taxa no longer limited by grazing. We conclude that vegetation communities can respond rapidly to warming as long as colonization is facilitated by available space or structural change. In the subalpine grasslands studies, changes were mainly driven by land management. These communities have a dense vegetation cover and newly arriving herbaceous species preferring warmer conditions may take some time to establish themselves. However, climate disturbances, such as exceptional drought, may accelerate community changes by opening gaps for new species.
Temperature controls ecosystem CO2 exchange of an alpine meadow on the northeastern Tibetan Plateau
Authors: SAITO MAKOTO , KATO TOMOMICHI , TANG YANHONG
Published: November 2008

Alpine ecosystems are extremely vulnerable to climate change. To address the potential variability of the responses of alpine ecosystems to climate change, we examined daily CO2 exchange in relation to major environmental variables. A dataset was obtained from an alpine meadow on the Qinghai‐Tibetan Plateau from eddy covariance measurements taken over 3 years (2002–2004). Path analysis showed that soil temperature at 5 cm depth (Ts5) had the greatest effect on daily variation in ecosystem CO2 exchange all year around, whereas photosynthetic photon flux density (PPFD) had a high direct effect on daily variation in CO2 flux during the growing season. The combined effects of temperature and light regimes on net ecosystem CO2 exchange (NEE) could be clearly categorized into three areas depending on the change in Ts5: (1) almost no NEE change irrespective of variations in light and temperature when Ts5 was below 0 °C; (2) an NEE increase (i.e. CO2 released from the ecosystem) with increasing Ts5, but little response to variation in light regime when 0 °C≤Ts5≤8 °C; and (3) an NEE decrease with increase in Ts5 and PPFD when Ts5 was approximately >8 °C. The highest daily net ecosystem CO2 uptake was observed under the conditions of daily mean Ts5 of about 15 °C and daily mean PPFD of about 50 mol m−2 day−1. The results suggested that temperature is the most critical determinant of CO2 exchange in this alpine meadow ecosystem and may play an important role in the ecosystem carbon budget under future global warming conditions.
Ectomycorrhizal fungi associated with Pinus sylvestris seedlings respond differently to increased carbon and nitrogen availability: implications for ecosystem responses to global change
Authors: ALBERTON ODAIR , KUYPER THOMAS W.
Published: November 2008

The ectomycorrhizal (ECM) symbiosis can cause both positive and negative feedback with trees under elevated CO2. Positive feedback arises if the additional carbon (C) increases both nutrient uptake by the fungus and nutrient transfer to the plant, whereas negative feedback results from increased nutrient uptake and immobilization by the fungus and reduced transfer to the plant. Because species of ECM fungi differ in their C and nitrogen (N) demand, understanding fungal species‐specific responses to variation in C and N supply is essential to predict impacts of global change. We investigated fungal species‐specific responses of ECM Scots pine (Pinus sylvestris) seedlings under ambient and elevated CO2 (350 or 700 μL L−1 CO2) and under low and high mineral N availability. Each seedling was associated with one of the following ECM species: Hebeloma cylindrosporum, Laccaria bicolor and Suillus bovinus. The experiment lasted 103 days. During the final 27 days, seedlings were labeled with 14CO2 and 15N. Most plant and fungal parameters were significantly affected by fungal species, CO2 level and N supply. Interactions between fungal species and CO2 were also regularly significant. At low N availability, elevated CO2 had the smallest impact on the photosynthetic performance of seedlings inoculated with H. cylindrosporum and the largest impact on seedlings with S. bovinus. At ambient CO2, increasing N supply had the smallest impact on seedlings inoculated with S. bovinus and the largest on seedlings inoculated with H. cylindrosporum. At low N availability, extraradical hyphal length increased after doubling CO2 level, but this was significant only for L. bicolor. At ambient CO2, increasing N levels reduced hyphal length for both H. cylindrosporum and S. bovinus, but not for L. bicolor. We discuss the potential interplay of two major elements of global change, elevated CO2 and increased N availability, and their effects on plant growth. We conclude that increased N supply potentially relieves mycorrhiza‐induced progressive N limitation under elevated CO2.
Quantities of mineral N in soil and concentrations of nitrate‐N in groundwater in four grassland‐based systems of dairy production on a clay‐loam soil in a moist temperate climate
Authors: Humphreys J. , Casey I. A. , Darmody P. , O’Connell K. , Fenton O. , Watson C. J.
Published: November 2008

This study examined the quantity of mineral N in soil and nitrate‐N losses to groundwater from grassland‐based dairy production in 2001 and 2002. There were four treatments with different inputs of N, through fertilizers, concentrates and biological fixation, and four associated stocking densities. Nitrogen inputs were 205, 230, 300 and 400 kg ha−1, respectively, and annual stocking densities were 1·75, 2·10, 2·50 and 2·50 cows ha−1. There were 18 cows per treatment. Grazed herbage accounted for 0·64, grass‐silage for 0·26 and concentrates 0·10 of annual DM consumed by the cows. Quantities of mineral N (nitrate‐N and ammonium‐N) in soil were measured, following extraction in 2 M KCl (1:2 w/v) shaken continuously for 2 h, on three occasions between late September and early February each winter. Concentrations of nitrate‐N in groundwater from wells inserted vertically to a depth of 1 m were determined throughout both winters. Quantities of mineral N in the soil increased (P < 0·001) with higher N inputs and declined (P < 0·001) with later sampling date. There were no relationships between nitrate‐N concentrations in groundwater and N inputs, N surpluses, deposition of excreta‐N at the soil surface and soil mineral N during both winters. Low losses of nitrate‐N to groundwater were primarily attributed to high rates of denitrification associated with a heavy soil texture, wet anaerobic soil conditions, relatively high organic carbon contents throughout the soil profile and mild soil temperatures throughout the year. Uptake of N by herbage made an important contribution to low N losses over the winter.
Growth of individual tillers and tillering rate of Lolium perenne and Bromus stamineus subjected to two defoliation frequencies in winter in Argentina
Authors: Berone G. D. , Lattanzi F. A. , Agnusdei M. G. , Bertolotti N.
Published: November 2008

The aims of the experiment were to (i) test whether the higher leaf elongation rate per tiller (LERT) of Bromus stamineus D. than Lolium perenne L. at moderately low temperatures was maintained at high defoliation frequencies and (ii) explore responses in tiller dynamics during the onset of the cool season in the south‐east of the humid Pampas region in Argentina. The following treatments were applied: defoliation frequency at the 3·0‐leaf stage (i.e. one‐leaf lifespan), which is considered optimal, and higher defoliation frequency at the 1·5‐leaf stage (i.e. half‐of‐a‐leaf lifespan). The higher defoliation frequency reduced leaf elongation rate in both the species but it did not affect the leaf appearance rate. This confirms previous studies on several C3 grasses, suggesting a similar pattern of response. Changes in tiller size are proposed as a possible mechanism to explain such long‐term defoliation effects on leaf elongation rates. Responses in tiller production depended on the species considered. The higher defoliation frequency caused a reduction in site‐filling which led to lower tiller production rates in L. perenne but not in B. stamineus. Thus, B. stamineus maintained the advantage in LERT over L. perenne and its tiller production was not affected when defoliated at frequencies higher than those considered optimal.
Sequence independent interferon‐α induction by multimerized phosphodiester DNA depends on spatial regulation of Toll‐like receptor‐9 activation in plasmacytoid dendritic cells
Authors: Haas Tobias , Schmitz Frank , Heit Antje , Wagner Hermann
Published: November 2008

Single‐stranded versus multimeric phosphorothioate‐modified CpG oligodeoxynucleotides (ODNs) undergo differential endosomal trafficking upon uptake into plasmacytoid dendritic cells (pDCs), correlating with Toll‐like receptor‐9‐dependent pDC maturation/activation (single‐stranded B‐type CpG ODN) or interferon‐α (IFN‐α) induction (multimeric A‐type CpG ODN), respectively. As was recently shown, IFN‐α production, other than by CpG ODNs, can also be induced in a sequence‐independent manner by phosphodiester (PD) ODNs multimerized by 3′ poly‐guanosine (poly‐G) tails. We investigate here the type of endosomal trafficking responsible for IFN‐α induction by natural PD ODN ligands. We show that 3′ extension with poly‐G tails leads to multimerization of single‐stranded PD ODNs and to enhanced cellular uptake into pDCs. While monomeric PD ODNs, which induce CpG‐dependent Toll‐like receptor‐9 stimulation and pDC maturation/activation, localized to late endosomal/lysosomal compartments, the poly‐G multimerized PD ODNs, which induce CpG‐independent IFN‐α production, located to vesicles with a distinct, ‘early’ endosomal phenotype. We conclude that poly‐G‐mediated multimerization of natural PD ODNs allows for sequence‐independent, Toll‐like receptor‐9‐dependent IFN‐α induction in pDCs by combining three distinct effects: relative protection of sensitive PD ODNs from extracellular and intracellular DNase degradation, enhanced cellular uptake and preferential early endosomal compartmentation.
The interaction of monocytes with rheumatoid synovial cells is a key step in LIGHT‐mediated inflammatory bone destruction
Authors: Ishida Satoru , Yamane Shoji , Nakano Saori , Yanagimoto Toru , Hanamoto Yukie , Maeda‐Tanimura Miki , Toyosaki‐Maeda Tomoko , Ishizaki Jun , Matsuo Yoshiyuki , Fukui Naoshi , Itoh Tsunetoshi , Ochi Takahiro , Suzuki Ryuji
Published: November 2008

Formation of osteoclasts and consequent joint destruction are hallmarks of rheumatoid arthritis (RA). Here we show that LIGHT, a member of the tumour necrosis factor (TNF) superfamily, induced the differentiation into tartrate‐resistant acid phosphatase (TRAP)‐positive multinucleated cells (MNCs) of CD14+ monocytes cocultured with nurse‐like cells isolated from RA synovium, but not of freshly isolated CD14+ monocytes. Receptor activator of nuclear factor‐κB ligand (RANKL) enhanced this LIGHT‐induced generation of TRAP‐positive MNCs. The MNCs showed the phenotypical and functional characteristics of osteoclasts; they showed the expression of osteoclast markers such as cathepsin K, actin‐ring formation, and the ability to resorb bone. Moreover, the MNCs expressed both matrix metalloproteinase 9 (MMP‐9) and MMP‐12, but the latter was not expressed in osteoclasts induced from CD14+ monocytes by RANKL. Immunohistochemical analysis showed that the MMP‐12‐producing MNCs were present in the erosive areas of joints in RA, but not in the affected joints of osteoarthritic patients. These findings suggested that LIGHT might be involved in the progression of inflammatory bone destruction in RA, and that osteoclast progenitors might become competent for LIGHT‐mediated osteoclastogenesis via interactions with synoviocyte‐like nurse‐like cells.
Critical thinking ability of new graduate and experienced nurses
Authors: Fero Laura J. , Witsberger Catherine M. , Wesmiller Susan W. , Zullo Thomas G. , Hoffman Leslie A.
Published: November 2008

Title.  Critical thinking ability of new graduate and experienced nurses.

Aim.  This paper is a report of a study to identify critical thinking learning needs of new and experienced nurses.

Background.  Concern for patient safety has grown worldwide as high rates of error and injury continue to be reported. In order to improve patient safety, nurses must be able to recognize changes in patient condition, perform independent nursing interventions, anticipate orders and prioritize.

Methods.  In 2004–2006, a consecutive sample of 2144 newly hired nurses in a university‐affiliated healthcare system completed the Performance Based Development System Assessment consisting of 10 videotaped vignettes depicting change in patient status. Results were reported as meeting or not meeting expectations. For nurses not meeting expectations, learning needs were identified in one of six subcategories.

Results.  Overall, 74·9% met assessment expectations. Learning needs identified for nurses not meeting expectations included initiating independent nursing interventions (97·2%), differentiation of urgency (67%), reporting essential clinical data (65·4%), anticipating relevant medical orders (62·8%), providing relevant rationale to support decisions (62·6%) and problem recognition (57·1%). Controlling for level of preparation, associate (P = 0·007) and baccalaureate (P < 0·0001) nurses were more likely to meet expectations as years of experience increased; a similar trend was not seen for diploma nurses (P = 0·10). Controlling for years of experience, new graduates were less likely to meet expectations compared with nurses with ≥10 years experience (P = 0·046).

Conclusion.  Patient safety may be compromised if a nurse cannot provide clinically competent care. Assessments such as the Performance Based Development System can provide information about learning needs and facilitate individualized orientation targeted to increase performance level.
Stages of Change – Continuous Measure (URICA‐E2): psychometrics of a Norwegian version
Authors: Lerdal Anners , Moe Britt , Digre Elin , Harding Thomas , Kristensen Frode , Grov Ellen K. , Bakken Linda N. , Eklund Marthe L. , Ruud Ireen , Rossi Joseph S.
Published: November 2008

Title.  Stages of Change – Continuous Measure (URICA‐E2): psychometrics of a Norwegian version.

Aim.  This paper is a report of research to translate the English version of the Stages of Change continuous measure questionnaire (URICA‐E2) into Norwegian and to test the validity of the questionnaire and its usefulness in predicting behavioural change.

Background.  While the psychometric properties of the Stages of Change categorical measure have been tested extensively, evaluation of the psychometric properties of the continuous questionnaire has not been described elsewhere in the literature.

Method.  Cross‐sectional data were collected with a convenience sample of 198 undergraduate nursing students in 2005 and 2006. The English version of URICA‐E2 was translated into Norwegian according to standardized procedures.

Findings.  Principal components analysis clearly confirmed five of the dimensions of readiness to change (Precontemplation Non‐Believers, Precontemplation Believers, Contemplation, Preparation and Maintenance), while the sixth dimension, Action, showed the lowest Eigenvalue (0·93). Findings from the cluster analysis indicate distinct profiles among the respondents in terms of readiness to change their exercise behaviour.

Conclusion.  The URICA‐E2 was for the most part replicated from Reed’s original work. The result of the cluster analysis of the items associated with the factor ‘Action’ suggests that these do not adequately measure the factor.
Patients’ opinions of acute chest pain care: a qualitative evaluation of Chest Pain Units
Authors: Johnson Maxine , Goodacre Steve , Tod Angela , Read Susan
Published: November 2008

Title. Patients’ opinions of acute chest pain care: a qualitative evaluation of Chest Pain Units.

Aim. This paper is a report of a study to explore the experiences of individuals receiving Chest Pain Unit care and routine Emergency Department care for acute chest pain.

Background. Chest Pain Units were established in the United States of America with the aim of reducing admissions and costs, whilst improving quality of life and care satisfaction. Trials showed these units to be safe and practical; however, there was a need to establish whether Chest Pain Units could be cost‐effective in the United Kingdom, and whether use of a nurse‐led protocol could be acceptable to patients.

Method. We carried out 26 semi‐structured interviews in 2005–2006 with patients across seven trial Chest Pain Units in the United Kingdom (14 in intervention sites and 12 in control sites) to explore issues that patients considered were important in their care experiences, and to develop possible explanations for the main trial outcomes. We analysed transcripts using the Framework approach to identify themes relating to care experiences.

Findings. Differences in care experiences were more distinct between individual sites than between control and intervention sites. Satisfaction with care was high overall. Interactions with healthcare professionals, in particular specialist nurses, were valued in terms of reassurance, calming effect and competence. Indications for care improvement concerned information‐giving about investigations, diagnosis, and self‐care advice. Patients with non‐cardiac causes needed to feel more supported after discharge.

Conclusion. Differences between modes of care may not coincide with identified trial outcomes. Qualitative methods can identify aspects of care that improve patient acceptability. The specialist nurse role appears particularly important in providing satisfactory individualized chest pain care.
Historical biogeography and phenotype‐phylogeny ofChroodiscus(lichenized Ascomycota: Ostropales: Graphidaceae)
Authors: Lücking Robert , Papong Khwanruan , Thammathaworn Achra , Boonpragob Kansri
Published: November 2008

Aim To analyse the historical biogeography of the lichen genusChroodiscususing a phenotype‐based phylogeny in the context of continental drift and evolution of tropical rain forest vegetation.

Location All tropical regions (Central and South America, Africa, India, Southeast Asia, north‐east Australia).

Methods We performed a phenotype‐based phylogenetic analysis and ancestral character state reconstruction of 14 species of the lichen genusChroodiscus, usingpaup* andmesquite; dispersal–vicariance analysis (DIVA) and dispersal–extinction–cladogenesis (DEC) modelling to trace the geographical origin of individual clades; and ordination and clustering by means ofpc‐ord, based on a novel similarity index, to visualize the biogeographical relationships of floristic regions in whichChroodiscusoccurs.

Results The 14 species ofChroodiscusshow distinctive distribution patterns, with one pantropical and one amphi‐Pacific taxon and 12 species each restricted to a single continent. The genus comprises four clades. DIVA and DEC modelling suggest a South American origin ofChroodiscusin the mid to late Cretaceous (120–100 Ma), with subsequent expansion through a South American–African–Indian–Southeast Asian–Australian dispersal route and late diversification of theargillaceusclade in Southeast Asia. Based on the abundance of extant taxa, the probability of speciation events inChroodiscusis shown to be extremely low. Slow dispersal of foliicolous rain forest understorey lichens is consistent with estimated phylogenetic ages of individual species and with average lengths of biological species intervals in fungi (10–20 Myr).

Main conclusions The present‐day distribution ofChroodiscuscan be explained by vicariance and mid‐distance dispersal through the interconnection or proximity of continental shelves, without the need for recent, trans‐oceanic long‐distance dispersal. Phylogenetic reconstruction and age estimation forChroodiscusare consistent with the ‘biotic ferry’ hypothesis: a South American origin and subsequent eastward expansion through Africa towards Southeast Asia and north‐eastern Australia via the Indian subcontinent. The present‐day pantropical distributions of many clades and species of foliicolous lichens might thus be explained by eastward expansion through continental drift, along with the evolution of modern rain forests starting 120 Ma, rather than by the existence of a hypothetical continuous area of pre‐modern rain forest spanning South America, Africa and Southeast Asia during the mid and late Cretaceous.
Landscape fluidity – a unifying perspective for understanding and adapting to global change
Authors: Manning Adrian D. , Fischer Joern , Felton Adam , Newell Barry , Steffen Will , Lindenmayer David B.
Published: November 2008

Rapid, human‐induced global change presents major challenges to researchers, policy‐makers and land managers. Addressing these challenges requires an appreciation of the dynamics of ecological systems. Here, we propose ‘landscape fluidity’ as a perspective and research agenda from which to consider landscapes in the process of changing rapidly through both time and space. We define landscape fluidity as the ebb and flow of different organisms within a landscape through time. A range of existing ideas, themes and practical approaches are relevant to landscape fluidity, and we use a case study of scattered tree landscapes in south‐eastern Australia to illustrate the benefits of a landscape fluidity perspective. We suggest that a focus on landscape fluidity can bring a renewed emphasis on change in landscapes and so help unify a range of currently separate research themes in biogeography, ecology, palaeoecology and conservation biology.
Searching for heat in a marine biodiversity hotspot
Authors: Bellwood David R. , Meyer Christopher P.
Published: November 2008

Coral reefs exhibit highly congruent patterns of biodiversity, with a prominent hotspot in the Indo‐Australian Archipelago (IAA). Unlike many terrestrial systems, the IAA hotspot exhibits extensive latitudinal and longitudinal biodiversity gradients. Conflicting hypotheses have highlighted the importance of the area as a centre of origin, overlap or accumulation, with the location of endemics being used as the primary criterion for testing these hypotheses, by identifying the presumed geographical origins of species. We evaluate the utility of marine endemics for resolving these hypotheses, and examine recent molecular phylogenetic evidence for coral reef species that has revealed the antiquity of the endemics and the other species that make up this hotspot. These analyses emphasize the importance of the IAA in the survival rather than the origins of species.
Prognostic role of the glucometabolic status assessed in a metabolically stable phase after a first acute myocardial infarction: the SHEEP study
Authors: Janszky I. , Hallqvist J. , Ljung R. , Ahlbom A. , Hammar N.
Published: November 2008

Objectives.  Our objective was to examine fasting glucose and insulin levels in patients surviving 3 months after a first AMI in relation to long‐term prognosis.

Design.  A total of 1167 consecutive patients between 45 and 70 years with a first nonfatal AMI underwent a standardized clinical examination and were followed for a mean of 8 years for total and cardiac mortality and hospitalization for nonfatal cardiovascular disease. Impaired fasting glucose (IFG) was defined as fasting glucose between 5.6 and 7 mmol L−1 and a level ≥7 mmol L−1 as newly detected diabetes. Patients with a fasting glucose level <5.6 mmol L−1 and without a history of diabetes were classified as normoglycemic (NG). An estimate of insulin resistance was calculated using the homeostasis model assessment (HOMA).

Results.  We recorded 219 deaths, 121 deaths from cardiac causes, during the follow‐up period. After adjustment for several potential confounders, hazard ratios for total mortality were 1.36 (95% confidence interval 0.93–1.99, P = 0.11), 2.27 (1.26–4.09, P = 0.006) and 2.15 (1.43–3.21, P < 0.001) for patients with IFG, newly detected diabetes and history of diabetes when compared to the NG group. Cardiac mortality, risk of hospitalization for recurrent nonfatal AMI, stroke or heart failure generally showed a similar pattern to that of total mortality. Insulin level and HOMA values were also associated with increased risk for recurrent events.

Conclusions.  We confirmed that both known and newly detected diabetes is a strong prognostic factor in AMI. In addition, our findings suggest that glucose levels below the diabetes cut off value might also predict poor long‐term prognosis when assessed in a metabolically stable phase.
Subjective food intake ability in relation to maximal bite force among Korean adults
Authors: KIM B. I. , JEONG S. H. , CHUNG K. H. , CHO Y. K. , KWON H. K. , CHOI C. H.
Published: November 2008

Summary  This study examined the relationship between the subjective food intake of 30 food types and their objective bite force to identify the key food items within the 30 food types to achieve a greater depth of masticatory function in Korean adults. A sample of 308 (112 males and 196 females) adults over the age of 20 (average age, 48·6) was selected among patients who visited four dental hospitals in Seoul, Korea. The subjective masticatory ability was evaluated through an interview with food intake ability questionnaires consisting of 30 food types ranging from hard to soft using a five‐step Likert scale. The objective maximal bite force was measured using pressure‐sensitive films. The relationship between the food intake ability and bite force was analysed and stratified according to age, gender, number of post‐canine teeth lost and several clinical oral health indicators. The key foods were selected using correlation and factor analysis. The subjective food intake ability between the 30 foods and key foods were tested by cluster and one‐way anova analysis. The Pearson’s correlation coefficient between food intake ability and bite force was 0·45 (P < 0·01). The five key food items selected were dried cuttlefish, raw carrot, dried peanut, cubed white radish kimchi and caramel. The correlation coefficient between the food intake ability and bite force of these items was 0·51 (P < 0·01). These results suggest that the subjective food intake ability using the 30 and five key foods can be used to evaluate the masticatory function in Korean adults.
Flies in the ointment: a morphological and molecular comparison of Lucilia cuprina and Lucilia sericata (Diptera: Calliphoridae) in South Africa
Authors: TOURLE R. , DOWNIE D. A. , VILLET M. H.
Published: November 2008

Abstract Complementary nuclear (28S rRNA) and mitochondrial (COI) genes were sequenced from blowflies that phenotypically resembled Lucilia cuprina (W.), Lucilia sericata (Meigen) or exhibited characters of both species. The aim was to test a long‐held hypothesis that these species hybridize under natural conditions in South Africa (Ullyett, 1945). Blowflies were obtained predominantly from the Cape Town metropolitan area, but reference samples were acquired for L. sericata from Pretoria. Several L. cuprina‐like flies were shown to possess a conflicting combination of nuclear and mitochondrial genes that has also been seen in Hawaiian specimens. Homoplasy, sampling of pseudogenes, hybridization and incomplete lineage sorting are discussed as possible hypotheses for the pattern and the latter is concluded to represent the most likely explanation.
Correlation of chromosomes 1p and 19q status and expressions of O6‐methylguanine DNA methyltransferase (MGMT), p53 and Ki‐67 in diffuse gliomas of World Health Organization (WHO) grades II and III: a clinicopathological study
Authors: Huang L. , Jiang T. , Yuan F. , Li G.‐L. , Cui Y. , Liu E.‐Z. , Wang Z.‐C.
Published: November 2008

Aims: The objective of the present study was to verify the correlation of chromosomes 1p and 19q status and expressions of O6‐methylguanine DNA methyltransferase (MGMT), p53 and Ki‐67 in diffuse gliomas of World Health Organization grades II and III. Methods: A series of 146 diffuse gliomas, including 45 oligodendrogliomas, 42 oligoastrocytomas and 59 astrocytomas, were analysed by denaturing high‐performance liquid chromatography for 1p and 19q status and by immunohistochemistry for MGMT, p53 and Ki‐67 expression patterns. The molecular alterations were then correlated with clinicopathological characteristics and with each other. Results: Loss of heterozygosity (LOH) on 1p, combined LOH on 1p and 19q, low MGMT expression and high Ki‐67 expression were associated with oligodendroglial tumours, whereas high p53 expression was associated with astrocytic and mixed tumours. LOH on 1p and low MGMT expression were associated with grade II oligodendroglial tumours, whereas high expressions of p53 and Ki‐67 were associated with grade III oligodendroglial tumours. In addition, high Ki‐67 expression was associated with grade III astrocytomas. LOH on 1p and LOH on 19q were associated with nontemporal oligodendroglial tumours. Nonrandom associations were found between LOH on 1p and LOH on 19q, MGMT expression and p53 expression, and MGMT expression and Ki‐67 expression, whereas mutual exclusions were found between LOH on 1p and 19q and p53 expression, and LOH on 1p and Ki‐67 expression. Conclusions: The present study revealed significant interrelationships of the investigated molecular alterations and clinicopathological characteristics in diffuse gliomas of World Health Organization grades II and III, which support a promising role of molecular markers in the diagnostic assessment of these neoplasms.