bluuebunny/crossref_metadata_2025_split huggingface dataset:
Endemic species and ecosystem sensitivity to climate change in Namibia
Authors: THUILLER WILFRIED , MIDGLEY GUY F. , HUGHES GREG O. , BOMHARD BASTIAN , DREW GILL , RUTHERFORD MICHAEL C. , WOODWARD F. IAN 
Published: March 2006

AbstractWe present a first assessment of the potential impacts of anthropogenic climate change on the endemic flora of Namibia, and on its vegetation structure and function, for a projected climate in ∼2050 and ∼2080. We used both niche‐based models (NBM) to evaluate the sensitivity of 159 endemic species to climate change (of an original 1020 plant species modeled) and a dynamic global vegetation model (DGVM) to assess the impacts of climate change on vegetation structure and ecosystem functioning.Endemic species modeled by NBM are moderately sensitive to projected climate change. Fewer than 5% are predicted to experience complete range loss by 2080, although more than 47% of the species are expected to be vulnerable (range reduction >30%) by 2080 if they are assumed unable to migrate. Disaggregation of results by life‐form showed distinct patterns. Endemic species of perennial herb, geophyte and tree life‐formsare predicted to be negatively impacted in Namibia, whereas annual herb and succulent endemic species remain relatively stable by 2050 and 2080. Endemic annual herb species are even predicted to extend their range north‐eastward into the tree and shrub savanna with migration, and tolerance of novel substrates. The current protected area network is predicted to meet its mandate by protecting most of the current endemicity in Namibia into the future. Vegetation simulated by DGVM is projected to experience a reduction in cover, net primary productivity and leaf area index throughout much of the country by 2050, with important implications for the faunal component of Namibia's ecosystems, and the agricultural sector. The plant functional type (PFT) composition of the major biomes may be substantially affected by climate change and rising atmospheric CO2– currently widespread deciduous broad leaved trees and C4 PFTs decline, with the C4 PFT particularly negatively affected by rising atmospheric CO2 impacts by ∼2080 and deciduous broad leaved trees more likely directly impacted by drying and warming. The C3 PFT may increase in prominence in the northwestern quadrant of the country by ∼2080 as CO2 concentrations increase. These results suggest that substantial changes in species diversity, vegetation structure and ecosystem functioning can be expected in Namibia with anticipated climate change, although endemic plant richness may persist in the topographically diverse central escarpment region.
A study of Gleason score interpretation in different groups of UK pathologists; techniques for improving reproducibility
Authors: Griffiths D F R , Melia J , McWilliam L J , Ball R Y , Grigor K , Harnden P , Jarmulowicz M , Montironi R , Moseley R , Waller M , Moss S , Parkinson M C ,   in collaboration with the participating pathologists listed
Published: March 2006

Aims:  To test the effectiveness of a teaching resource (a decision tree with diagnostic criteria based on published literature) in improving the proficiency of Gleason grading of prostatic cancer by general pathologists.Methods:  A decision tree with diagnostic criteria was developed by a panel of urological pathologists during a reproducibility study. Twenty‐four general histopathologists tested this teaching resource. Twenty slides were selected to include a range of Gleason score groups 2–4, 5–6, 7 and 8–10. Interobserver agreement was studied before and after a presentation of the decision tree and criteria. The results were compared with those of the panel of urological pathologists.Results:  Before the teaching session, 83% of readings agreed within ± 1 of the panel's consensus scores. Interobserver agreement was low (κ = 0.33) compared with that for the panel (κ = 0.62). After the presentation, 90% of readings agreed within ± 1 of the panel's consensus scores and interobserver agreement amongst the pathologists increased to κ = 0.41. Most improvement in agreement was seen for the Gleason score group 5–6.Conclusions:  The lower level of agreement among general pathologists highlights the need to improve observer reproducibility. Improvement associated with a single training session is likely to be limited. Additional strategies include external quality assurance and second opinion within cancer networks.
The combination of millimetres of cancer and Gleason index in core biopsy is a predictor of extraprostatic disease
Authors: López J I , Etxezarraga C 
Published: March 2006

Aims:  The Gleason index (GI) is related to several pathological endpoints in radical prostatectomy (RP) specimens, including the risk of extraprostatic disease (ED). The amount of tumour (TM) in core biopsy (CB) specimens also correlates with staging. The aim was to determine whether the sum of the relative statistical weights of GI and TM in CBs strengthens the prediction of ED in RPs.Methods and results:  A series of 290 RPs and their previous respective CBs were reviewed. TM and the GI were blindly evaluated in CBs and statistically correlated with ED in RPs. A total of 60 (20.6%) RPs showed ED. The logistic regression model indicated that all cases with > 22 mm of cancer in CB showed ED in RP. All cases with a GI > 7 and > 12 mm of cancer in CB displayed ED. Finally, Pearson's χ2 revealed that 80% of cases with a GI > 7 and ≥ 5 mm of cancer in CB showed ED in RP.Conclusions:  The combined evaluation of GI and TM in CB is a useful method to strengthen the prediction of ED, is based on two simple morphological criteria and may be used as an additional tool to choose the best treatment modality.
Role of natural interferon‐producing cells and T lymphocytes in porcine monocyte‐derived dendritic cell maturation
Authors: Guzylack‐Piriou Laurence , Piersma Sytse , McCullough Kenneth , Summerfield Artur 
Published: March 2006

SummaryMaturation of dendritic cells (DC) is a key immunological process regulating immune responses to pathogens and vaccines, as well as tolerance and autoimmune processes. Consequently, the regulation of DC maturation should reflect these multifaceted immunological processes. In the present study, we have defined the role of particular cytokines, Toll‐like receptor (TLR) ligands and T lymphocytes in the porcine monocyte‐derived DC (MoDC). Interferon‐α (IFN‐α) alone was a poor inducer of MoDC maturation, but in association with tumour necrosis factor‐α (TNF‐α), or TLR ligands such as lipopolysaccharide and polyinosinic‐polycytidylic acid I:C, an up‐regulation of major histocompatibility complex II and CD80/86 expression was noted, along with reduced endocytic activity. In contrast, TNF‐α alone or in combination with the TLR ligands was a poor inducer of DC maturation, but co‐operated with T‐lymphocytes in the presence of antigen to induce DC maturation. Natural interferon producing cells (NIPC, or plasmacytoid DCs) represent a danger‐recognition system of the immune defences, and can respond to viruses not otherwise recognized as posing a danger. Indeed, MoDC did not respond to transmissible gastroenteritis virus (TGEV), whereas NIPC produced high levels of IFN‐α and TNF‐α after TGEV stimulation. Moreover, supernatants from the stimulated NIPC induced maturation in MoDCs. These matured MoDCs displayed an enhanced ability to present antigen to and thus stimulate T cells. Taken together, the present work demonstrates that maturation of MoDC not only results from TLR signalling, but can require co‐operation with various cell types – principally NIPC and activated T cells – which would reflect the particular immunological situation.
Extending point pattern analysis for objects of finite size and irregular shape
Authors: WIEGAND THORSTEN , KISSLING W. DANIEL , CIPRIOTTI PABLO A. , AGUIAR MARTÍN R. 
Published: March 2006

SummaryWe use a grid‐ and simulation‐based approach to extend point pattern analysis to deal with plants of finite size and irregular shape, and compare the results of our approach with that of the conventional point approximation. The plants are approximated by using an underlying grid and may occupy several adjacent grid cells depending on their size and shape. Null models correspond to that of point pattern analysis but need to be modified to account for the finite size and irregular shape of plants.We use a mapped area of a grass‐shrub steppe in semi‐arid Patagonia, Argentina, to show that the shrub community is essentially randomly structured, but that shrubs facilitate grasses in their immediate neighbourhood.The occurrence of this random spatial structure provides important new information on the biology of shrub populations. In general, previous data from semi‐arid and arid ecosystems have shown that adult shrubs tend to show over‐dispersed patterns, whereas juveniles are clumped.We find that the point approximation may produce misleading results (i) if plant size varies greatly, (ii) if the scale of interest is of the same order of magnitude as the size of the plants, and (iii) if the plants of a given pattern are constrained through competition for space by the presence of other plants. The point approximation worked well in all other cases, but usually depicted weaker significant effects than when the size and shape of plants were taken into account.Our approach to quantifying small‐scale spatial patterns in plant communities has broad applications, including the study of facilitation and competition. Ecologists will be able to use the software available to take advantage of these methods.
The evolution of rewards: seed dispersal, seed size and elaiosome size
Authors: EDWARDS WILL , DUNLOP MICHAEL , RODGERSON LOUISE 
Published: March 2006

SummaryWe examine the relationship between the reward offered to ants to disperse seeds (elaiosome size) and seed size, and the possible mechanisms that may generate this relationship in Australian plant species.We used seed and elaiosome sizes from our own data set containing 87Acaciaspecies, supplemented with 22 species from a previously published data set, and 98 ‘Other species’ from 51 genera in 25 families, also from published data.The relationship between ln(elaiosome size) and ln(seed size) was determined using standard major axis (SMA) regression for both data sets. For the Other data set we also determined the relationship among species independent of the differences between genera, among genera independent of the differences between families, among genera and among families. We used SMA to test for differences in slopes between groups.We found a significant common slope amongst all subsets of the larger data set. The estimated common slope and the 95% confidence interval for the relationship between ln(elaiosome size) and ln(seed size) across all data sets fell above one (1.24, 95%CI = 1.17–1.32), suggesting positive allometry. Slopes were also significantly positive and strikingly similar between theAcaciaspecies data set and the Other species data sets. Similar positive allometry was shown in the ‘other’ species data set among genera and families, and among species independent of genus means (‘species effects’).Significant and consistent relationships between taxonomic levels, independent of relationships at other levels, along with significant relationships at the species level, and similarity of slopes, suggest independent convergence towards an underlying functional relationship that has persisted over long evolutionary periods. Our results therefore suggest that ants have been agents of selection on seed traits.Such a functional relationship might result from a trade‐off in ant foraging behaviour between the benefit of the reward (elaiosome) and the cost of the dispersal (determined by seed size). Slopes > 1 would then suggest that ants need more than proportionally larger rewards to remove larger seeds.
Root competition: beyond resource depletion
Authors: SCHENK H. JOCHEN 
Published: March 2006

SummaryRoot competition is defined as a reduction in the availability of a soil resource to roots that is caused by other roots. Resource availability to competitors can be affected through resource depletion (scramble competition) and by mechanisms that inhibit access of other roots to resources (contest competition, such as allelopathy).It has been proposed that soil heterogeneity can cause size‐asymmetric root competition. Support for this hypothesis is limited and contradictory, possibly because resource uptake is affected more by the amount and spatial distribution of resource‐acquiring organs, relative to the spatial distribution of resources, than by root system sizeper se.Root competition intensity between individual plants generally decreases as resource availability (but not necessarily habitat productivity) increases, but the importance of root competition relative to other factors that structure communities may increase with resource availability.Soil organisms play important, and often species‐specific, roles in root interactions.The findings that some roots can detect other roots, or inert objects, before they are contacted and can distinguish between self and non‐self roots create experimental challenges for those attempting to untangle the effects of self/non‐self root recognition, self‐inhibition and root segregation or proliferation in response to competition. Recent studies suggesting that root competition may represent a ‘tragedy‐of‐the‐commons’ may have failed to account for this complexity.Theories about potential effects of root competition on plant diversity (and vice versa) appear to be ahead of the experimental evidence, with only one study documenting different effects of root competition on plant diversity under different levels of resource availability.Roots can interact with their biotic and abiotic environments using a large variety of often species‐specific mechanisms, far beyond the traditional view that plants interact mainly through resource depletion. Research on root interactions between exotic invasives and native species holds great promise for a better understanding of the way in which root competition may affect community structure and plant diversity, and may create new insights into coevolution of plants, their competitors and the soil community.
Seed predation, not seed dispersal, explains the landscape‐level abundance of an early‐successional plant
Authors: ORROCK JOHN L. , LEVEY DOUGLAS J. , DANIELSON BRENT J. , DAMSCHEN ELLEN I. 
Published: March 2006

Summary
Plants may not occur in a given area if there are no suitable sites for seeds to establish (microsite limitation), if seeds fail to arrive in suitable microsites (dispersal limitation) or if seeds in suitable microsites are destroyed by predators (predator limitation).
We conducted a large‐scale study to determine the importance of dispersal limitation and predator limitation in affecting the distribution of pokeweed, Phytolacca americana, in 401‐ha experimental patches arrayed in eight groups of five patches distributed across a 300‐km2 region.
Microsite limitation was minimized by clearcutting and burning existing vegetation, creating the type of disturbed habitat in which P. americana readily germinates and establishes. The role of dispersal limitation was examined by adding approximately 7000 seeds to each of eight patches in March 2000. The role of seed predation was examined in all 40 patches using experimental exclosures from June 2000 to July 2001.
The number of P. americana plants in September 2000 was unchanged by seed addition. However, fewer P. americana plants were found in patches where seed predators removed more P. americana seeds from experimental exclosures. These data suggest that P. americana is not limited by seed dispersal. Rather, in habitats where microsites are readily available, the abundance of P. americana among patches appears to be limited by the activities of seed predators.
When dispersal and microsites are not limiting, the role of local seed predators can be important for generating emergent, large‐scale patterns of plant abundance across landscapes. Moreover, because predators may generate large‐scale patterns that resemble other forms of limitation and predators may target specific species, predator impacts should be more frequently incorporated into experiments on the role of seed limitation and plant community composition.
Diurnal variation of prescribing pattern of primary care doctors in Bahrain
Authors: Damanhori Awatif H. H. , Al Khaja Khalid A. J. , Sequeira Reginald P. , Al‐Ansari Thuraya M. 
Published: March 2006

AbstractRationale, aims and objectives  To evaluate the variation in prescribing by primary care doctors during the morning and the evening clinics and to determine whether these prescribing patterns are influenced by doctors’ training background.Methods  A retrospective prescription‐based study was carried out in 17 out of 20 primary care health centres in Bahrain distributed across the Kingdom.Results  A total of 4472 prescriptions containing 10 588 drug‐items covering the prescribing practice of approximately 90% primary care doctors were analysed. Paracetamol was the most commonly prescribed drug in both clinics. Drugs such as diclofenac sodium, amoxycillin, ibuprofen, chlorpheniramine, hyoscine butylbromide, Actifed®, Benylin® and xylometazoline were the most commonly prescribed drugs to patients attending morning and evening clinics with a considerable variation in ordinal ranking of proportions. As regards morning clinic, chlorpheniramine and Fefol® were prescribed by the family doctors (FDs) more often than by the general practitioners (GPs) (P < 0.05), whereas, multivitamins were prescribed by the GPs more often than by the FDs (P = 0.001). During the evening clinic, however, ibuprofen, chlorpheniramine, bromhexine and xylometazoline were prescribed by the FDs in a rate significantly higher than that prescribed by the GPs (P < 0.05). The prevalence of acute and/or chronic morbidities in patient attending clinics was estimated based on the therapeutic indication for drugs used. The mean number of drugs per prescription was 2.41 ± 1.3. Prescriptions containing three or more drugs comprised 41.7% of all prescriptions. The GPs had a greater tendency to practice polypharmacy than the FDs.Conclusion  A significant diurnal variation in prescribing, and polypharmacy practice were related to the training background of the doctors. This quantitative study provides the baseline data for monitoring primary care prescribing practices in Bahrain. To further evaluate the underlying factors that influence drug use indicators, a qualitative study is needed.
Low testosterone levels are associated with carotid atherosclerosis in men
Authors: SVARTBERG J. , VON MÜHLEN D. , MATHIESEN E. , JOAKIMSEN O. , BØNAA K. H. , STENSLAND‐BUGGE E. 
Published: March 2006

Abstract.Objective.  To study the relationship between endogenous sex hormone levels and intima‐media thickness (IMT) of the carotid artery measured by ultrasonography.Design.  Population‐based cross‐sectional study.Methods.  Sex hormone levels measured by immunoassay, anthropometric measurements and IMT was studied in 1482 men aged 25–84 years participating in the 1994–1995 Tromsø study. The data were analysed with partial correlation, multiple linear regression and logistic regression analysis.Results.  Linear regression models showed that total testosterone and sex hormone‐binding globulin levels, but not calculated free testosterone, serum oestradiol or dehydroepiandrosterone sulphate levels were inversely associated with the age‐adjusted IMT (P = 0.008 and P < 0.001 respectively). These associations were independent of smoking, physical activity, blood pressure and lipid levels, but were not independent of body mass index (BMI). Excluding men with cardiovascular disease (CVD) did not materially change these results. In a logistic regression model adjusted for the confounding effect of CVD risk factors, men with testosterone levels in the lowest quintile (<9.0 nmol L−1) had an independent OR = 1.51 (P = 0.015) of being in the highest IMT quintile.Conclusions.  We found an inverse association between total testosterone levels and IMT of the carotid artery in men that was present also after excluding men with CVD, but was not independent of BMI. The clinical relevance of this, however, is uncertain and needs to be investigated in a clinical setting.
Diet and physical activity in relation to overall mortality amongst adult diabetics in a general population cohort
Authors: TRICHOPOULOU A. , PSALTOPOULOU T. , ORFANOS P. , TRICHOPOULOS D. 
Published: March 2006

Abstract.Objectives.  To evaluate the effect on overall and cardiovascular mortality of diet and physical activity amongst diabetic persons.Design.  Population‐based prospective investigation, from 1993 to mid‐2004, in the Greek arm of the European Prospective Investigation into Cancer and Nutrition.Setting.  Volunteers from the general adult Greek population.Subjects.  From an original sample of 28 572 volunteers, 1013 were taking at enrolment drugs for diabetes mellitus, had no missing information on the study variables and no comorbidity. Diet was assessed at baseline through a validated questionnaire. Proportional hazards regression was used to assess the relation of dietary factors and physical activity with mortality.Interventions.  None.Main outcome measures.  Mortality ratios overall and from cardiovascular causes.Results.  During 4579 person‐years, 80 deaths have occurred, 46 of which from cardiovascular causes. Physical activity was strongly inversely associated with mortality. Two nutritional variables were significantly associated with diabetic mortality, with hazard ratios for increases of daily intake by one standard deviation being 1.31 for eggs [95% confidence interval (95% CI) 1.07 to 1.60] and 1.82 for saturated lipids (95% CI, 1.14 to 2.90). These two associations were considerably stronger for cardiovascular mortality. Waist‐to‐height ratio was positively, whereas hip circumference inversely associated with mortality. No significant interactions with gender for any of the study variables were evident.Discussion.  Amongst confirmed diabetic persons, increased physical activity is associated with significant reduction of mortality, whereas increased consumption of eggs and saturated fats is associated with significant increase of mortality. Monounsaturated lipids are preferable for diabetic persons.
Radiographic measure of aorta calcification is a site‐specific predictor of bone loss and fracture risk at the hip
Authors: BAGGER Y. Z. , TANKÓ L. B. , ALEXANDERSEN P. , QIN G. , CHRISTIANSEN C. ,   THE PROSPECTIVE EPIDEMIOLOGICAL RISK FACTORS STUDY GROUP
Published: March 2006

Abstract.Objective.  To investigate whether aorta calcification (AC) – a surrogate marker of atherosclerosis – is an independent indicator of low bone mass density (BMD), accelerated bone loss, and risk of future fractures in postmenopausal women.Design.  A prospective epidemiological study. Follow‐up period was 7.5 years.Setting.  Community‐based sample followed by a research institute.Subjects.  A total of 2662 generally healthy postmenopausal women with a mean age of 65.0 ± 7.1 years at baseline.Main outcome measures.  Annual rate of changes in BMD (DEXA) and AC (X‐rays), vertebral fractures (X‐rays), hip fractures (questionnaire).Results.  Advanced AC at baseline was significantly associated with lower BMD and accelerated bone loss from the proximal femur. In a multivariate logistic regression model, age (OR 1.1, 95% CI 1.0–1.2, P = 0.02), body mass index (BMI; OR 0.9, 95% CI 0.8–1.0, P = 0.03) and the severity of AC (OR 2.3, 95% CI 1.1–4.8, P = 0.03) were independent predictors of hip fractures. Adjusted OR for vertebral fracture was 1.2 (95% CI 1.0–1.5, P = 0.12).Conclusions.  Aorta calcification seems to independently contribute to the development of osteoporosis in the proximal femur. Further studies are needed to clarify whether effective atherosclerosis prevention lowers hip fracture risk.