bluuebunny/crossref_metadata_2025_split huggingface dataset:
Invasive mutualisms and the structure of plant–pollinator interactions in the temperate forests of north‐west Patagonia, Argentina
Authors: MORALES CAROLINA L. , AIZEN MARCELO A. 
Published: November 2005

Summary

Alien species may form plant–animal mutualistic complexes that contribute to their invasive potential. Using multivariate techniques, we examined the structure of a plant–pollinator web comprising both alien and native plants and flower visitors in the temperate forests of north‐west Patagonia, Argentina. Our main objective was to assess whether plant species origin (alien or native) influences the composition of flower visitor assemblages. We also examined the influence of other potential confounding intrinsic factors such as flower symmetry and colour, and extrinsic factors such as flowering time, site and habitat disturbance.
Flowers of alien and native plant species were visited by a similar number of species and proportion of insects from different orders, but the composition of the assemblages of flower‐visiting species differed between alien and native plants.
The influence of plant species origin on the composition of flower visitor assemblages persisted after accounting for other significant factors such as flowering time, bearing red corollas, and habitat disturbance. This influence was at least in part determined by the fact that alien flower visitors were more closely associated with alien plants than with native plants. The main native flower visitors were, on average, equally associated with native and alien plant species.
In spite of representing a minor fraction of total species richness (3.6% of all species), alien flower visitors accounted for > 20% of all individuals recorded on flowers. Thus, their high abundance could have a significant impact in terms of pollination.
The mutualistic web of alien plants and flower‐visiting insects is well integrated into the overall community‐wide pollination web. However, in addition to their use of the native biota, invasive plants and flower visitors may benefit from differential interactions with their alien partners. The existence of these invader complexes could contribute to the spread of aliens into novel environments.
Experimental scale and precipitation modify effects of nitrogen addition on a plant pathogen
Authors: STRENGBOM JOACHIM , ENGLUND GÖRAN , ERICSON LARS 
Published: November 2005

Summary

We examined how the interaction between the parasitic fungus Valdensia heterodoxa and its host plant Vaccinium myrtillus was affected by nitrogen (N) additions over 5 years in a boreal forest in northern Sweden. To examine whether the N effect was scale‐dependent we fertilized different sized plots (1, 10, 100, 1000 and 5000 m2 in area) with N corresponding to 12.5 or 50 kg N ha−1 year−1. We also examined how the N effect varied with the amount of summer precipitation.
Disease incidence of the parasite increased following N addition and the effect was, on average, stronger in large than in small plots. The effect of plot size was significant for both N addition levels during the final year, but only marginally significant for the entire experimental period. Dispersal distances of ascospores and conidia were short, suggesting that high net emigration probabilities of propagules from small plots could explain the lower disease incidence in such plots and thereby the scale dependence of the disease.
Disease incidence was also positively correlated with precipitation. High summer precipitation enhanced the N effect, suggesting that precipitation may modify the effects of N deposition on plant–parasite interactions. This may complicate predictions of future effects of N deposition as precipitation patterns are expected to change as a result of climate change.
Our results suggest that small‐scale fertilization experiments may underestimate future large‐scale effects of N deposition, and indicate the need for increased awareness of the problems associated with scaling results from experiments using small‐scale manipulation of environmental variables.
Large‐scale spatial dynamics of a specialist plant pathogen in a fragmented landscape
Authors: LAINE ANNA‐LIISA , HANSKI ILKKA 
Published: November 2005

SummarySpatial population structure may have profound consequences for the stability and evolution of host–pathogen interactions. We used a large‐scale 4‐year dataset to study the spatial dynamics ofPodosphaera plantaginis, an obligate pathogen ofPlantago lanceolatain the Åland Islands in south‐west Finland, where the host populations are mostly very small and have a scattered spatial distribution.The fraction of host populations infected was low but highly variable among years, ranging from 1% to 4.7%, with frequent local extinction and colonization events. Demographic stochasticity associated with regular seasonal declines and severe drought was responsible for the high extinction rate. Frequent colonizations of host populations close to the pathogen source populations suggest that there is substantial gene flow in the pathogen at spatial scales up to 1 km.Occurrence of the pathogen was strongly and positively correlated with the logarithm of host population size, the proximity of a road to the host population (presumably facilitating dispersal) and the proximity of the coastline (presumably due to microclimatic conditions favouring pathogen development).The high turnover rate of the pathogen, distance‐dependent dispersal and regional variation in host–pathogen encounter rates have consequences for the coevolutionary dynamics betweenPlantago lanceolataandPodosphaera plantaginis.
Soil nutrients and beta diversity in the Bornean Dipterocarpaceae: evidence for niche partitioning by tropical rain forest trees
Authors: PAOLI GARY D. , CURRAN LISA M. , ZAK DONALD R. 
Published: November 2005

Summary

The relative importance of niche‐ and dispersal‐mediated processes in structuring diverse tropical plant communities remains poorly understood. Here, we link mesoscale beta diversity to soil variation throughout a lowland Bornean watershed underlain by alluvium, sedimentary and granite parent materials (c. 340 ha, 8–200 m a.s.l.). We test the hypothesis that species turnover across the habitat gradient reflects interspecific partitioning of soil resources.
Floristic inventories (≥ 1 cm d.b.h.) of the Dipterocarpaceae, the dominant Bornean canopy tree family, were combined with extensive soil analyses in 30 (0.16 ha) plots. Six samples per plot were analysed for total C, N, P, K, Ca and Mg, exchangeable K, Ca and Mg, extractable P, texture, and pH.
Extractable P, exchangeable K, and total C, N and P varied significantly among substrates and were highest on alluvium. Thirty‐one dipterocarp species (n = 2634 individuals, five genera) were recorded. Dipterocarp density was similar across substrates, but richness and diversity were highest on nutrient‐poor granite and lowest on nutrient‐rich alluvium.
Eighteen of 22 species were positively or negatively associated with parent material. In 8 of 16 abundant species, tree distribution (≥ 10 cm d.b.h.) was more strongly non‐random than juveniles (1–10 cm d.b.h.), suggesting higher juvenile mortality in unsuitable habitats. The dominant species Dipterocarpus sublamellatus (> 50% of stems) was indifferent to substrate, but nine of 11 ‘subdominant’ species (> 8 individuals ha−1) were substrate specialists.
Eighteen of 22 species were significantly associated with soil nutrients, especially P, Mg and Ca. Floristic variation was significantly correlated with edaphic and geographical distance for all stems ≥ 1 cm d.b.h. in Mantel analyses. However, juvenile variation (1–10 cm d.b.h.) was more strongly related to geographical distance than edaphic factors, while the converse held for established trees (≥ 10 cm d.b.h.), suggesting increased importance of niche processes with size class.
Pervasive dipterocarp associations with soil factors suggest that niche partitioning structures dipterocarp tree communities. Yet, much floristic variation unrelated to soil was correlated with geographical distance between plots, suggesting that dispersal and niche processes jointly determine mesoscale beta diversity in the Bornean Dipterocarpaceae.
Closing the gap: collaborative learning as a strategy to embed evidence within occupational therapy practice
Authors: Welch Amanda , Dawson Pamela 
Published: November 2005

AbstractRationale  The principles of clinical governance apply as guidelines for good practice to all practitioners. However, evidence‐based practice (EBP) is proving a challenge for practitioners who lack the confidence to consume published research. For therapists not wishing to undertake formal study there is a risk of becoming disempowered within a culture of EBP. Opportunities to develop skills in consuming research have focused on the information dissemination model that has limited effect. Mutual reflective learning processes are recommended to empower practitioners to bridge the theory‐practice gap.Aim  An action research approach investigated practice based collaborative learning as a catalyst to increase therapist's competence and confidence in consuming research and to explore the transition toward EB practitioner.Method and Results  A diagnostic survey reaffirmed therapist's lack of confidence in EBP. Formative interviews (n = 5) found an over reliance on professional craft and personal knowledge. Research knowledge was not included in participants’ construct of a good practitioner and engagement in higher order critical reflection was limited. Collaborative learning groups (n = 6) embedded in practice integrated research, theory, practice and critical reflection. Supported by the collegial learning environment, a learning package developed participants’ confidence and competence in consuming published research. Summative interviews (n = 5) evaluated the group and found that therapists were empowered to incorporate propositional knowledge into their clinical reasoning, engage in critical reflection and challenge their practice. They felt confident to incorporate EBP into their continuing professional development plans. Sustainability of these changes requires commitment from the therapists and the workplace.
Impact of cost containment measures on medical liability
Authors: Callens S. , Volbragt I. , Nys H. 
Published: November 2005

AbstractRationale  Owing to the growing health care expenditure and the need to improve efficiency, public authorities have since the 1980s changed their policy with respect to health care. Financial pressures encouraged them to investigate methods to control health care costs. One recent method is the enactment of cost containment measures based on clinical practice guidelines (CPGs) that provide financial or administrative sanctions.Aims and objectives  This article describes the legal value of CPGs, the evolution towards cost containment measures based on CPGs, and finally the legal value of these new cost containment measures. It questions whether these measures may have an impact on the medical liability rules and it wants to open the debate on the legal value of these measures based vis‐à‐vis the professional autonomy of the physician and patients’ rights on quality care.Methods  The research for this article is based on a comparative analysis of the legal literature and jurisprudence of a number of legal systems.Results and Conclusions  The article concludes that, as a result of the rising costs, it becomes increasingly difficult for a physician to balance his duty to take care on the one hand and his duty to control costs on the other. Maintaining a high standard of care towards patients becomes difficult. Consequently, one wonders whether the law should then allow the standard of care to be adjusted according to the available means. Until now, courts in a fault based system have not been willing to accept such an adjustment of the standard of care, but it might well be possible that this attitude will change in case of no‐fault compensation systems.
Quantifying the impact of survivor treatment bias in observational studies
Authors: Austin Peter C. , Mamdani Muhammad M. , Van Walraven Carl , Tu Jack V. 
Published: November 2005

AbstractRationale  Observational cohort studies are frequently used to measure the impact of therapies on the time to a particular outcome. Treatment often has a time‐variant nature since it is frequently initiated at varying times during a patient’s follow‐up. Studies in the medical literature frequently ignore the time‐dependent nature of treatment exposure. Survivor treatment bias can arise when the time dependent nature of treatment exposure is ignored since patients who survived to receive treatment may be healthier than patients who died prior to receipt of treatment.Aims and objectives  The objective of the current study was to explicitly quantify the magnitude of survivor‐treatment bias.Methods  Monte Carlo simulations using parameters obtained from an analysis of patients admitted to hospital with a diagnosis of acute myocardial infarction in Ontario, Canada.Results and conclusions  When the true treatment was null (hazard ratio of 1), estimated treatment effects varied from a 4% reduction in mortality to a reduction in mortality of 27% when the time varying nature of the treatment was ignored. Furthermore, survivor‐treatment bias increased as the time required foe exposed patients to receive treatment increased. Similarly, survivor treatment bias was amplified as exposure was defined to be exposure at any time prior to mortality compared to exposure within a fixed time interval starting at the time origin. Ignoring the time‐dependent nature of treatment results in overly optimistic estimates of treatment effects. Depending on the period required for patients to initiate therapy, treatments with no effect on survival can appear to be strongly associated with improved survival. The current study is the first to explicitly quantify the magnitude of bias that results from ignoring the time‐varying nature of treatment exposure in survival studies.
An educational programme for peer review groups to improve treatment of chronic heart failure and diabetes mellitus type 2 in general practice
Authors: Kasje Willeke N. , Denig Petra , Stewart Roy E. , De Graeff Pieter A. , Haaijer‐Ruskamp Flora M. 
Published: November 2005

AbstractRationale, aims and objectives  Peer review groups are considered helpful for quality improvement in primary care. An interactive educational programme for small peer groups was developed, focusing on the implementation of newly developed treatment guidelines. The aim is to evaluate the effect of the programme on adherence to treatment guidelines in general practice.Methods  A cluster randomized trial using a balanced incomplete block design was used; one arm received a programme on treatment of chronic heart failure (CHF), the other on hypertension treatment in diabetes mellitus type 2 (T2DM). A random sample of 10 CHF and 10 T2DM patients per GP was drawn, for whom data were extracted from electronic patient records 1 years before and 6 months after the intervention. The outcomes were prescribing of ACE inhibitors, and antihypertensive treatment in T2DM. The effect was analysed separately for both programmes using multilevel regression models.Results  All 27 peer review groups in one region in the Netherlands were randomized, of which 16 participated. No significant effects were observed in the CHF group or in the T2DM group. The opportunity for change was limited, as only 53% of the CHF patients and 60% of the T2DM patients had a contact with their GP between the intervention and follow‐up measurement.Conclusion  The peer review programme was not successful for changing the treatment of chronic patients, although the programme focused on dealing with barriers perceived by the participants. Not all problems perceived can be solved in a peer group discussion.
Impact of an educational intervention to promote condom use among the male partners of HIV positive women
Authors: Silveira Mariângela Freitas da , Santos Iná Silva dos 
Published: November 2005

AbstractRationale aims and objectives   Promoting the secondary prevention of HIV transmission is essential.Method  An intervention. aimed at increasing condom use by partners. was delivered to HIV positive women attending a Brazilian clinic. It included educational advice delivered by doctors. and unlimited access to free condoms. A pre‐post design was used: 170 control group women were recruited. the intervention was implemented. and 170 intervention group women were then enrolled. All were interviewed at baseline. 30 and 60 days.Results  After training. doctors were more likely to provide advice on condom use. Reported use increased by 8.8% points (a 14.2% increase) in the intervention group after 30 days. and by 5.7 points (9.5%) in the control group (P = 0.52).Conclusion  The reasons why the intervention failed to reach a significant effect are discussed. as are the possible Public Health impact of a 14.2% increase in condom use among HIV positive women.
Evaluation of a community mental health carepath for early psychosis
Authors: Hanson Laura A. , Grypma Martha , Tee Karen A. , MacEwan G. William 
Published: November 2005

AbstractPurpose  To implement a carepath for early psychosis across all community mental health centres through the Early Psychosis Intervention Programme in the Fraser South Area of British Columbia, Canada.Methods  Prior to developing the carepath, chart reviews and interviews were performed to assess for adherence to published guidelines for early psychosis intervention. This assessment revealed the inadequacies of narrative recording and that core psychosocial interventions were inconsistently provided. The carepath developed included prompts for interventions and standardized assessments and ultimately replaced the charting system used in the mental health centres for early psychosis clients.Results and conclusions One‐year evaluation revealed some improvements in clinical practice but also identified other areas that require further improvement. This project demonstrated that it is possible to successfully implement a carepath in community mental health and that doing so provides a standardized method for ongoing improvements in care.
Lessons from developing and running a clinical database for colorectal cancer
Authors: Sehgal Ashu , Davies Elizabeth 
Published: November 2005

AbstractBackground  Recent policy developments in the UK require the routine monitoring of the performance of cancer services. Developing and using clinical databases is one approach to meet this objective, but to date their implementation has been challenging.Objective  To describe the development of the Thames Cancer Registry clinical database for colorectal cancer, and to present the lessons learnt in the first five years since its establishment.Methods  Planning of this clinical database began in 1998. Detailed variables for the data set were derived by analysis of national standards and guidelines. Structured pro formas were designed to abstract data from clinical notes. A pilot study over 12 months collected 400 cases from seven hospital trusts in one cancer network. Data collection over the wider North Thames area began in 1999.Results  The number of new records entered each year into the database rose from 747 in 1999 to 1107 in 2002. By 2004, it held a total of 8500. However, participation and completeness of data collection varied between trusts. Currently only 18 of 26 trusts in the area submit data and only 12 have done so every year. Overall completeness for key demographic and treatment variables has been between 80 and 100% but less so for more detailed diagnostic and treatment variables (40–60%). Barriers to implementation in trusts could be grouped as organizational, professional and data‐related. Organizational barriers have included changes in the cancer networks, variability in trust commitment to different data sets and lack of personnel to enter data consistently. Professional barriers have included competing priorities and varying commitments within the multidisciplinary clinical teams. Data‐related barriers include the wide range of database formats that are used in trusts, and a tendency for data to be collected at the end of the year rather than continuously.Conclusions Creating and maintaining a clinical database is a time‐consuming and complex undertaking. Completeness of ascertainment and quality are major issues of concern. Key lessons from this project have been that the commitment of clinicians and the ability of trusts to provide consistent support for data collection are crucial.
Variations in the ability of general medical practitioners to apply two methods of clinical audit: a five‐year study of assessment by peer review
Authors: McKay John , Bowie Paul , Lough Murray 
Published: November 2005

AbstractIntroduction  Clinical audit has a central role in the NHS clinical governance agenda and the professional appraisal of medical practitioners in the UK. However, concerns have been raised about the poor design and impact of clinical audit studies and the ability of practitioners to apply audit methods. One method of making informed judgements on audit performance is by peer review. In the west of Scotland a voluntary peer review model has been open to general practitioners since 1999, while general practice trainees are compelled to participate as part of summative assessment. The study aimed to compare the outcomes of peer review for two methods of audit undertaken by different professional and academic groups of doctors.Methods  Participants submitted a criterion audit or significant event analysis in standard formats for review by two informed general practitioners (GPs) using appropriate instruments. Peer review outcome data and the professional status of doctors participating were generated by computer search. Differences in proportions of those gaining a satisfactory peer review for each group were calculated.Results  Of 1002 criterion audit submissions, 552 (55%) were judged to be satisfactory. GP registrars were significantly more likely than GP trainers (P < 0.001) and other established GP groups (P < 0.001) to gain a satisfactory peer review. GPs in non‐training practices were less likely to achieve a satisfactory review than registrars (P < 0.001) and colleagues in training practices (P < 0.001). Of 883 SEA submissions, 541 (65%) were judged as satisfactory, with all groups gaining a similar proportion of satisfactory assessments, although GP registrars may have outperformed non‐training practice GPs (P = 0.05).Conclusion  A significant proportion of GPs may be unable to adequately apply audit methods, potentially raising serious questions about the effectiveness of clinical audit as a health care improvement policy in general medical practice.