bluuebunny/crossref_metadata_2025_split huggingface dataset:
Invasibility of grassland and heath communities exposed to extreme weather events – additive effects of diversity resistance and fluctuating physical environment
Authors: Kreyling Juergen , Beierkuhnlein Carl , Ellis Laura , Jentsch Anke 
Published: August 2008

Understanding the resistance of plant communities to invasion is urgent in times of changes in the physical environment due to climate change and changes in the resident communities due to biodiversity loss. Here, we test the interaction between repeated drought or heavy rainfall events and functional diversity of grassland and heath communities on invasibility, measured as the number of plant individuals invading from the matrix vegetation.Invasibility of experimental plant communities was influenced by extreme weather events, although no change in above‐ground productivity of the resident communities was observed. Drought decreased invasibility while heavy rainfall increased invasibility, a pattern that is consistent with the fluctuating resource hypothesis. Higher community diversity generally decreased invasibility, which can be explained by a combination of the fluctuating resource hypothesis and niche theory. The effects of the physical environment (extreme weather events) and diversity resistance (community composition) were additive, as they were independent from each other.Differences in the composition of invading species sets were found, and Indicator Species Analysis revealed several invading species with significant affinity to one particular extreme weather event or community composition. This finding supports niche theory and contradicts neutral species assembly.Our data supports theories which predict decreased resistance of plant communities due to both increased climate variability and biodiversity loss. The effects of these two factors, however, appear to be independent from each other.
Measurement of testosterone in the diagnosis of hypogonadism in the ageing male
Authors: Wheeler M. J. , Barnes S. C. 
Published: August 2008

SummaryMany males in their old age demonstrate symptoms consistent with hypogonadism. With the introduction of new and more convenient methods of testosterone replacement treatment of these males is more practical. The diagnosis of hypogonadism in the older male has been controversial with some clinicians suggesting that symptoms should be treated without due reliance on testosterone concentrations. However, most professional bodies have proposed that a low testosterone concentration should be part of the diagnosis. This is, in turn, reliant on the testosterone measurement being reliable and read against an appropriate reference range. This review looks at the factors that can influence the interpretation of testosterone results for the ageing male.
Effects of aromatase inhibition in hypogonadal older men: a randomized, double‐blind, placebo‐controlled trial
Authors: Burnett‐Bowie Sherri‐Ann M. , Roupenian Kristen C. , Dere Melissa E. , Lee Hang , Leder Benjamin Z. 
Published: August 2008

SummaryObjective  To assess the effects of sustained aromatase inhibition in older hypogonadal men.Design and patients  In a 1‐year randomized, double‐blind, placebo‐controlled trial, 88 men, aged 60 years and older with testosterone levels between 5·2 and 10·4 nmol/l on a single measure or between 10·4 and 12·1 nmol/l on two consecutive measures, and with symptoms of hypogonadism were recruited. Subjects received either anastrozole 1 mg daily or placebo.Measurements  Changes in gonadal steroid hormone levels, body composition [by computerized tomography (CT) and dual X‐ray absorptiometry (DXA)], strength, prostate specific antigen (PSA), symptoms of benign prostatic hypertrophy (BPH), haematocrit and lipid levels were assessed.Results  Testosterone levels increased from 11·2 ± 3·3 nmol/l at baseline to 18·2 ± 4·8 nmol/l at month 3 (P < 0·0001 vs. placebo) while bioavailable testosterone levels increased from 2·7 ± 0·8 nmol/l at baseline to 5·4 ± 1·7 nmol/l at month 3 (P < 0·0001 vs. placebo). Testosterone and biotestosterone levels peaked at month 3 and then declined by month 12 (though they remained significantly higher than baseline and greater than placebo). E2 levels decreased from 55·8 ± 15·4 pmol/l at baseline to 42·2 ± 13·6 pmol/l at month 3 and then remained stable (P < 0·0001). Body composition and strength did not change, nor did PSA, BPH symptoms, haematocrit or lipid levels.Conclusions  Anastrozole administration normalized androgen production in older hypogonadal men and decreased E2 production modestly. These alterations did not improve body composition or strength.
Ion release characteristics, precipitate formation and sealing ability of a potential new root canal filling material
Authors: Alani A. , Knowles J. , Ng Y.‐L. , Gulabivala K. 
Published: August 2008

Aim  To test a new polycaprolactone (PCL)/bioactive glass (BAG) composite as a root filling material capable of producing a seal under moist conditions by precipitation.Methodology  Formulations of PCL/BAG composites were made using the solvent casting method and then modified into a form physically deliverable into root canals. Root canals of single‐rooted extracted human teeth were modified by de‐coronation and removal of the apical 2 mm of the root. Canal instrumentation was performed with gates glidden drills (1% NaOCl and 17% EDTA irrigation) to achieve a degree of standardization of shape. The canals were filled with the composites using warm vertical compaction (the composites are thermoplastic and behave like gutta‐percha) but without root canal sealer. A group of obturated teeth (n = 6 per composite formulation) was monitored for ion release (Na+, Ca2+, PO43‐, P2O74‐, P3O93‐ and P5O105‐) into solution from the apical portion using ion chromatography. Three composite formulations were used to fill 10 roots each and half (n = 5) exposed to saline, whilst others were sectioned immediately; both were examined by light and scanning electron microscopy to evaluate adaptation, precipitate and film formation. A further group of 30 roots was obturated to evaluate seal formation by dye penetration; a control group (n = 10) consisted of conventional gutta‐percha and Roth's sealer delivered in like manner to the test material; two test groups (n = 10 each) were obturated with a composite formulation producing the optimal precipitate, the apices of teeth in one group were immersed in saline for 7 days and the other not.Results  All samples released various amounts of ions which followed inversely to the concentration of iron oxide within the bioactive glass. Adaptation of the experimental material was better than the gutta‐percha control groups. The formation of precipitate was evident in some specimens; in others film formation and dentine tubule entry by the material was observed. The dye penetration test showed that composite root filling specimens immersed apically in saline for 7 days had significantly less leakage (almost none) than those not immersed in saline at all (P < 0.001) or the gutta‐percha control (P < 0.001).Conclusions  Polycaprolactone–bioactive glass composites may have potential as ‘sealer‐free’ root filling material because of their ion release, precipitate formation and short‐term seal.
Utility of the FISH technique in conjunction with confocal microscopy to study the intraradicular microflora of teeth associated with apical periodontitis
Authors: Iacovidou A. , Mordan N. , Figueiredo J. A. P. , Gulabivala K. 
Published: August 2008

Aim  To develop protocols to investigate the reliability of fluorescence in situ hybridization (FISH) using 16SrRNA probes to examine the composition and distribution of the biofilm along the length of the root canal using confocal laser scanning microscopy (CLSM).Methodology  Resin‐embedded mixed cultures of Porphymonas gingivalis and Fusobacterium. nucleatum (n = 108) and artificially infected dentine specimens (n = 6) were used to optimize the FISH protocol. The following hybridization variables were tested: hybridization temperature, incubation time, probe concentration, wash regime and buffer composition. Ten extracted human teeth (13 roots) associated with apical periodontitis were fixed, processed and embedded in resin for generating sections to be viewed under conventional light microscopy (LM) and CLSM (FISH). Roots were sectioned transversely into thirds and each third sectioned longitudinally to reveal the canal; semi‐thin sections were obtained. Universal EUB338 and specific (POGI) probes were used in an optimized protocol for bacterial detection and viewing of association between microbial flora and canal structures. Representative sections of each root segment were examined with each microscopy technique. Observations were recorded systematically.Results  After many trials and errors, a protocol for FISH was successfully refined for predictable application using the EUB338 probe but the specific probe (POGI) failed to give predictable and specific binding. Bacteria were detected in all 10 teeth by both microscopy techniques. A biofilm structure comprising of rods, cocci and filaments was observed in each sample. Overall, more bacterial cells were evident coronally than apically and penetration of the dentinal tubules was evident solely in the coronal and middle thirds. PMNs were found in some of the apical and middle root segments. An ‘amorphous substrate’ was consistently detected in the canal lumen using the CSLM but not using LM; it was contiguous with the visible cells and microorganism structures, implying that it formed an interface with these visible structures, possibly giving shape to their boundaries. Apparently loose‐lying bacteria may therefore be ’enclosed’ within a ‘structure’ unseen by LM, and therefore may correctly be termed biofilm rather than planktonic.Conclusions  A protocol for FISH was successfully developed for a universal 16SrRNA probe; its application to teeth with apical periodontitis gave interesting insights about the juxtaposition of bacteria and canal contents.
The effect of purmorphamine on murine osteoclast activity
Authors: Ypsilanti K. , Gulabivala K. , Buxton P. 
Published: August 2008

Aims  The aim of the study was (i) to establish and characterize a model to evaluate the effect of purmorphamine on murine osteoclastic activity; (ii) to test the hypothesis that purmorphamine‐stimulated osteoclasts would resorb test calcium phosphate surfaces more than controls. The alternative hypothesis was that purmorphamine‐stimulated osteoclasts would be associated with significantly less resorption than baseline controls.Methodology  In the characterization phase, cultured osteoclasts were able to resorb a calcium phosphate coating (CaP) allowing a simple but effective model to assay their activity. Bone marrow from 50 neonatal mice provided the source of osteoclasts that were seeded onto 100 CaP‐coated discs to evaluate the effect of purmorphamine on their activity. Culture medium was used as a baseline control and bisphosphonate as negative control.Results  The characterization phase of the study demonstrated that a suitable CaP coating could be reproducibly precipitated onto the discs and that resorption through the action of TRAP‐positive, multi‐nucleate cells was quantifiable. Bisphosphonate negative controls showed no resorption. From a starting sample of 100 CaP discs, attrition through development and infection problems left five experiment and control pairs, the analysis of which showed that purmorphamine‐stimulated osteoclasts were associated with significantly (P = 0.043) less resorption than baseline controls, indicating that it probably had an inhibitory effect on osteoclast function.Conclusions  Purmorphamine is an important bone agonist that could possibly be combined with grafting materials and induce bone regeneration. Within the limitations of the study, it can be concluded that purmorphamine does not induce differentiation of precursors into osteoclasts, supporting the alternative hypothesis. The next step would be to evaluate the properties of purmorphamine in conjunction with grafting materials (e.g. hydroxylapatite) by using implantation and usage tests in animals. In this way, the effect of purmorphamine on bone regeneration can be assessed and conclusions about its usefulness can be drawn.
Application of failure mode and effect analysis (FMEA) and cause and effect analysis for industrial processing of common octopus (Octopus vulgaris) – Part II
Authors: Arvanitoyannis Ioannis S. , Varzakas Theodoros H. 
Published: August 2008

SummaryFailure mode and effect analysis (FMEA) model was applied in conjunction with cause‐and‐effect analysis for the risk assessment of octopus processing (Octopus vulgaris). Critical control points were identified and implemented in the cause‐and‐effect diagram (also known as Ishikawa, tree diagram and fishbone diagram). The main emphasis was put on the quantification of risk assessment by determining the risk priority numbers (RPN) per identified processing hazard. Chemically contaminated product, decomposed raw materials, scombrotoxin presence in the final product, incorrectly labelled product, storage in cans (foreign matter) and defective products, were identified as those with the highest RPN (378, 294, 280, 252, 245 and 144 respectively) and corrective actions were undertaken. Following the application of corrective actions, a second calculation of RPN values was carried out, leading to considerably lower values (below the upper acceptable limit of 130). It is concluded that the incorporation of FMEA analysis within the ISO2200 system of an octopus‐processing industry is imperative.
Conflicts between biodiversity conservation and development in a biosphere reserve
Authors: Ma Zhijun , Li Bo , Li Wenjun , Han Nianyong , Chen Jiakuan , Watkinson Andrew R. 
Published: August 2008

Summary

Integrating biodiversity conservation and the development of local communities is a major challenge for biosphere reserves. Their zonation (core, buffer and transition) is intended to promote biodiversity conservation and sustainable development, although only the core zone is legally constituted to conserve biological diversity. Inevitably, and especially in developing countries, the management of biosphere reserves has to reconcile trade‐offs between conservation and development, and address the pressures placed by local communities on the biodiversity resources of the reserve.
We studied the effects of development in the three zones of Yancheng Biosphere Reserve (eastern China) on the endangered red‐crowned crane Grus japonensis, the waterbird communities and the economic benefits to local communities. We tested the hypothesis that allowing different developments within each zone can reduce conflict between biodiversity conservation and community development.
The number of cranes in the reserve increased from 361 to approximately 1100 between 1982 and 1999, but declined markedly to 612 in 2003. The cranes also became increasingly concentrated in the core zone and switched to feeding predominantly in artificial habitats. The proportion of cranes in the core, buffer and transition zones was largely associated with the proportion of developed land area and the total number of cranes in the reserve as a whole.
Developments in the transition zone have reduced and degraded the wetlands, and have disadvantaged cranes and waterbirds. In contrast, the transformation of natural wetlands into artificial ones in the core zone has, to date, continued to support cranes and waterbirds. This has brought economic benefits to the reserve and local communities, but at the cost of the integrity of the wetland ecosystem as a whole.
Synthesis and applications. Despite an increase in the number of red‐crowned cranes in Yancheng Biosphere Reserve, their range has collapsed into the core of the reserve where there is now a substantial artificial wetland complex. Allowing development in all three zones, together with a lack of resources for conservation, appears to have contributed to the reserve becoming overdeveloped. The loss of ecosystem integrity across the reserve as a whole highlights the need for an ecosystem‐based approach to future management combined with the restoration of natural wetlands.
Habitat fragmentation and adaptation: a reciprocal replant–transplant experiment among 15 populations ofLychnis flos‐cuculi
Authors: Bowman Gillianne , Perret Catherine , Hoehn Sophie , Galeuchet David J. , Fischer Markus 
Published: August 2008

SummaryHabitat fragmentation and variation in habitat quality can both affect plant performance, but their effects have rarely been studied in combination. We thus examined plant performance in response to differences in habitat quality for a species subject to habitat fragmentation, the common but declining perennial herbLychnis flos‐cuculi.We reciprocally transplanted plants between 15 fen grasslands in north‐east Switzerland and recorded plant performance for 4 years.Variation between the 15 target sites was the most important factor and affected all measures of plant performance in all years. This demonstrates the importance of plastic responses to habitat quality for plant performance.Plants from smaller populations produced fewer rosettes than plants from larger populations in the first year of the replant–transplant experiment.Plant performance decreased with increasing ecological difference between grassland of origin and target grassland, indicating adaptation to ecological conditions. In contrast, plant performance was not influenced by microsatellite distance and hardly by geographic distance between grassland of origin and target grassland.Plants originating from larger populations were better able to cope with larger ecological differences between transplantation site and site of origin.Synthesis: In addition to the direct effects of target grasslands, both habitat fragmentation, through reduced population size, and adaptation to habitats of different quality, contributed to the performance ofL. flos‐cuculi. This underlines that habitat fragmentation also affects species that are still common. Moreover, it suggests that restoration projects involvingL. flos‐cuculishould use plant material from large populations living in habitats similar to the restoration site. Finally, our results bring into question whether plants in small habitat remnants will be able to cope with future environmental change.
Testing the spatial phylogenetic structure of local communities: statistical performances of different null models and test statistics on a locally neutral community
Authors: Hardy Olivier J. 
Published: August 2008

Summary

Analyzing the phylogenetic structure of natural communities may illuminate the processes governing the assembly and coexistence of species. For instance, an association between species co‐occurrence in local communities and their phylogenetic proximity may reveal the action of habitat filtering, niche conservatism and/or competitive exclusion.
Different methods were recently proposed to test such community‐wide phylogenetic patterns, based on the phylogenetic clustering or overdispersion of the species in a local community. This provides a much needed framework for addressing long standing questions in community ecology as well as the recent debate on community neutrality. The testing procedures are based on (i) a metric measuring the association between phylogenetic distance and species co‐occurrence, and (ii) a data set randomization algorithm providing the distribution of the metric under a given ‘null model’. However, the statistical properties of these approaches are not well‐established and their reliability must be tested against simulated data sets.
This paper reviews metrics and null models used in previous studies. A ‘locally neutral’ subdivided community model is simulated to produce data sets devoid of phylogenetic structure in the spatial distribution of species. Using these data sets, the consistency of Type I error rates of tests based on 10 metrics combined with nine null models is examined.
This study shows that most tests can become liberal (i.e. tests rejecting too often the null hypothesis that only neutral processes structured spatially the local community) when the randomization algorithm breaks down a structure in the original data set unrelated to the null hypothesis to test. Hence, when overall species abundances are distributed non‐randomly across the phylogeny or when local abundances are spatially autocorrelated, better statistical performances were achieved by randomization algorithms preserving these structural features. The most reliable randomization algorithm consists of permuting species with similar abundances among the tips of the phylogenetic tree. One metric, RPD‐DO, also proved to be robust under most simulated conditions using a variety of null models.
Synthesis. Given the suboptimal performances of several tests, attention must be paid to the testing procedures used in future studies. Guidelines are provided to help choosing an adequate test.
Interpreting and estimating measures of community phylogenetic structuring
Authors: Hardy Olivier J. , Jost Lou 
Published: August 2008

Summary

To characterize the spatial phylogenetic structure of communities, Hardy & Senterre (2007) (J. Ecol., 95, 493–506) partition Gini–Simpson diversity and its generalization, Rao's entropy, defining IST and PST as the proportion of diversity expressed among sites.
Interpreting IST as a measure of ‘differentiation’ between sites is inadequate because low values are actually compatible with high differentiation (low species sharing) in species rich communities. To avoid an inadequate use of IST, for example in conservation biology, we offer a more literal interpretation: IST expresses the ‘local species identity excess’. Similarly, PST expresses the ‘local phylogenetic similarity excess’.
Villéger & Mouillot (2008) (J. Ecol., 96, 845–848, this issue) argue that the equations of Hardy & Senterre (2007) to compute diversity are inadequate when sites differ in size, and they provide new expressions weighting sites by their sizes. We argue that whether sites must be weighted equally or not depends on the question being asked. Moreover, actual size and sample size must be distinguished, the latter being important for defining estimators.
Synthesis. The formulations given by Hardy & Senterre (2007) and by Villéger & Mouillot (2008) are both correct in the specific contexts we detail.