bluuebunny/crossref_metadata_2025 huggingface dataset:
Transgression narratives, dialogic voicing, and cultural change1
Authors: Menard‐Warwick Julia
Published: November 2005

The narrative discursively analyzed in this paper is taken from a larger study involving life history interviews with Latina/o immigrants in California. It exemplifies a type of narrative among these interviews in which tellers recount how they or their family members have broken with cultural expectations. In this story, the teller, a Nicaraguan woman, recounts how her uncle violated traditional values in her family by enlisting in the Sandinista army during wartime. Despite discursively distancing herself from this transgression, she ends by evaluating the transgressor and his recent accomplishments positively. Through an analysis of the appraisal strategies and interdiscursivity within this narrative, the paper contends that the narrators of such stories can go beyond managing deviations to dialogically position themselves among competing ‘social and historical voices’(Bakhtin 1981). Thus, the paper contends that transgression narratives represent the tellers’ efforts to come to terms with cultural changes in their communities.
Communities of practice:  Legitimacy not choice
Authors: Davies Bethan
Published: November 2005

Communities of practice has emerged as an alternative to other current sociolinguistic models such as speech communities and social networks, particularly in the area of language and gender. The valorization of non‐linguistic behaviours as adding further explanatory power to sociolinguistic models is timely: it has often been implicit in linguistic study (through ethnography) but rarely been given recognition. However, the types of self‐constituting communities of interest to sociolinguists are not the same as the communities of learning studied by Lave and Wenger (1991) and Wenger (1998). If this construct is to be useful to sociolinguists, then the mechanisms by which it models access, gate‐keeping and its internal hierarchy need development. Using Eckert's (2000) Belten High data, and other work on adolescent talk, it is argued that gaining legitimate peripheral participation is a matter of sanction from within the hierarchy. Individuals do not have open access to communities based solely on their desire to be part of that community and to take part in its practices. While practices may define the community, the community determines who has access to that practice.
Acquired C1‐inhibitor deficiency in a patient with systemic lupus erythematosus: a case report and review of the literature
Authors: Nettis E. , Colanardi M. C. , Loria M. P. , Vacca A.
Published: November 2005

The C1‐inhibitor (C1‐INH) is an important member of the serpin family which inhibits the first component of the human complement system and controls contact activation of the coagulation and kinin system. An acquired form of C1‐INH deficiency was recognized and classified as type I, which is characterized by accelerated catabolism of C1‐INH, whereas type II is defined by the presence of an autoantibody directed against the C1 inhibitor molecule. This study reports the case of a 32‐year‐old woman with systemic lupus erythematosus (SLE) who experienced recurrent angioedema because of an acquired C1‐INH deficiency. The relevant literature is reviewed.
Frailty predicts long‐term mortality in elderly subjects with chronic heart failure
Authors: Cacciatore F. , Abete P. , Mazzella F. , Viati L. , Della Morte D. , D’Ambrosio D. , Gargiulo G. , Testa G. , De Santis D. , Galizia G. , Ferrara N. , Rengo F.
Published: November 2005

Background  The elderly are characterized by a high prevalence of chronic heart failure (CHF) and frailty, which is a complex interaction of physical, psychological and social impairment. This study aimed to examine the predictive role of frailty on long‐term mortality in elderly subjects with CHF.

Materials and methods  The study assessed long‐term mortality after 12‐year follow up in 120 subjects with CHF and 1139 subjects without CHF, selected in 1992, from a random sample of the elderly population in the Campania region of Italy. Frailty was assessed according to a ‘Frailty Staging System’.

Results  Subjects with CHF were prevalently female (60%) and older than 75 years (mean 75·9 ± 6·7); subjects without CHF were prevalently female (56·4%) and younger than 75 years (mean 74·0 ± 6·3). In subjects with and without CHF stratified into classes of frailty there was a statistically significant increase in age, comorbidity, disability and low social support, and a decrease in MMSE score. Moreover, death progressively increased more with frailty in subjects (70·0% to 94·4%, P < 0·03) than in those without (43·8.% to 88·3%, P < 0·0001) CHF. The Kaplan–Meier analysis shows that at 9 years the probability of survival progressively decreased as frailty increased (45·5% to 0%) in subjects with CHF and from 62·8% to 25·9% in subjects without CHF. The Cox regression analysis indicated that frailty is predictive of mortality in the multivariate model adjusted for several variables including sex and age in subjects with and without CHF. Moreover, the analysis showed that frailty is more predictive of mortality in elderly subjects with CHF when it was analyzed either as continuous (1·48 vs. 1·36) or as a dummy (3 vs. 1 = 1·62 vs. 1·24) variable.

Conclusions  Thus mortality among elderly subjects with or without CHF increases with frailty. Moreover, frailty is more predictive of long‐term mortality in elderly subjects with than in those without CHF. Hence, frailty represents a new independent variable for predicting long‐term mortality in elderly subjects with CHF.
Strength and endurance training lead to different post exercise glucose profiles in diabetic participants using a continuous subcutaneous glucose monitoring system
Authors: Cauza E. , Hanusch‐Enserer U. , Strasser B. , Kostner K. , Dunky A. , Haber P.
Published: November 2005

Background  Although both strength training (ST) and endurance training (ET) seem to be beneficial in type 2 diabetes mellitus (T2D), little is known about post‐exercise glucose profiles. The objective of the study was to report changes in blood glucose (BG) values after a 4‐month ET and ST programme now that a device for continuous glucose monitoring has become available.

Materials and methods  Fifteen participants, comprising four men age 56·5 ± 0·9 years and 11 women age 57·4 ± 0·9 years with T2D, were monitored with the MiniMed (Northridge, CA, USA) continuous glucose monitoring system (CGMS) for 48 h before and after 4 months of ET or ST. The ST consisted of three sets at the beginning, increasing to six sets per week at the end of the training period, including all major muscle groups and ET performed with an intensity of maximal oxygen uptake of 60% and a volume beginning at 15 min and advancing to a maximum of 30 min three times a week.

Results  A total of 17 549 single BG measurements pretraining (619·7 ± 39·8) and post‐training (550·3 ± 30·1) were recorded, correlating to an average of 585 ± 25·3 potential measurements per participant at the beginning and at the end of the study. The change in BG‐value between the beginning (132 mg dL−1) and the end (118 mg dL−1) for all participants was significant (P = 0·028). The improvement in BG‐value for the ST programme was significant (P = 0·02) but for the ET no significant change was measured (P = 0·48). Glycaemic control improved in the ST group and the mean BG was reduced by 15·6% (Cl 3–25%).

Conclusion  In conclusion, the CGMS may be a useful tool in monitoring improvements in glycaemic control after different exercise programmes. Additionally, the CGMS may help to identify asymptomatic hypoglycaemia or hyperglycaemia after training programmes.
Gestational diabetes mellitus is associated with increased C‐reactive protein concentrations in the third but not second trimester
Authors: Leipold H. , Worda C. , Gruber C. J. , Prikoszovich T. , Wagner O. , Kautzky‐Willer A.
Published: November 2005

Objective Serum C‐reactive protein (CRP) concentrations were measured longitudinally throughout pregnancy to test the hypothesis that CRP could relate more closely to glucose tolerance than to adiposity.

Methods The CRP concentrations in pregnant women with normal glucose tolerance (NGT) and those with gestational diabetes mellitus (GDM) were measured at the same time as the oral glucose tolerance test (OGTT), at the 24th and 28th weeks of gestation and between the 37th and 38th weeks of gestation.

Results At the end of the third trimester, women with GDM had significantly higher CRP levels than women with NGT [median (interquartile range), 9·7 mg L−1 (5·4–16·0) and 5·7 mg L−1 (5·1–7·2); P < 0·001, respectively], but at the time of the diagnostic OGTT no significant difference between the two groups was observed. This was owing to a significant increase of CRP in women with GDM between the time of the OGTT and the 37th−38th gestational weeks [median (interquartile range), 1·9 mg L−1 (−2·2, 6·7); P = 0·01]; whereas, no change in CRP was found in women with NGT [median (interquartile range), −0·1 mg L−1 (−2·4, 3·1); P = 0·76]. Multiple linear regression analysis showed only a significant independent influence of GDM (P < 0·001) on maternal CRP concentrations in the 37th−38th gestational weeks and a significant influence of body mass index (P < 0·007), but no influence of GDM at the time of the OGTT.

Conclusion These data suggest that in women with gestational diabetes the CRP concentration is primarily related to the degree of adiposity until the second trimester and that thereafter impaired glucose metabolism appears to be the predominant predictor of changes in CRP.
Tumour necrosis factor alpha in fat redistribution syndromes associated with combination antiretroviral therapy in HIV‐1‐infected patients: potential role in subcutaneous adipocyte apoptosis
Authors: Domingo P. , Vidal F. , Domingo J. C. , Veloso S. , Sambeat M. A. , Torres F. , Sirvent J. J. , Vendrell J. , Matias‐Guiu X. , Richart C. ,   on behalf of the HIV‐FRS Study Group
Published: November 2005

Background  The pathogenesis of fat redistribution syndromes (FRS) observed in the setting of highly active antiretroviral therapy (HAART) for the treatment of HIV‐1‐infection remains elusive. A dysregulation of the tumour necrosis factor alpha (TNF‐α) system occurs in HIV‐infected patients with FRS.

Materials and methods  The study looked at both the in vivo and in vitro relationship between TNF‐α and the degree of subcutaneous adipocyte apoptosis in 60 HIV‐1‐infected patients on HAART with FRS, another 60 HIV‐1‐infected patients on HAART without FRS and 60 uninfected control patients. Apoptosis was assessed by the terminal deoxynucleotidyl transferase dUTP (deoxyuridine 5′‐triphosphate)‐digoxigenin Nick End Labelling (TUNEL) method. Soluble receptors of TNF‐α were determined by the sandwich enzyme immunoassay technique. The in vitro viability was assessed by staining with 3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5 diphenyltetrazolium bromide (MTT) and apoptosis by TUNEL.

Results  HIV‐1‐infected patients with FRS had significantly higher degrees of subcutaneous adipocyte apoptosis than those without FRS (P = 0·0001) and uninfected controls (P < 0·0001). There was a statistically significant association between serum levels of soluble TNF‐α receptors #1 and #2 and the degree of subcutaneous adipocyte apoptosis in patients with and without FRS (P < 0·0001 for both receptors). In vitro, the addition of TNF‐α (10 ng mL−1) to an adipocyte culture embedded with indinavir, either alone or in clinically relevant combinations with stavudine (d4T) and lamivudine (3TC), significantly decreased adipocyte viability (P = 0·0001) and increased adipocyte apoptosis (P < 0·0001) with respect to that observed with the addition of antiretrovirals alone.

Conclusions  TNF‐α plays a significant role in subcutaneous adipocyte apoptosis, which occurs in the setting of FRS in HIV‐1‐infected patients on highly active antiretroviral therapy.
Chorionic plate artery function and Doppler indices in normal pregnancy and intrauterine growth restriction
Authors: Mills T. A. , Wareing M. , Bugg G. J. , Greenwood S. L. , Baker P. N.
Published: November 2005

Background  In fetal growth restriction (FGR) abnormal umbilical artery (UA) Doppler waveform indices suggest increased vascular resistance and impaired placental blood flow. This study aimed to determine whether UA Doppler waveform indices were related to the vasoreactivity of placental chorionic plate small arteries in normal and FGR pregnancies.

Materials and methods  UA Doppler waveform analysis was performed 24 h before delivery in 23 normal term and 15 FGR pregnancies. Post‐delivery responses of chorionic plate arteries to vasoactive agents were examined using the technique of wire myography.

Results  Altered vascular reactivity to agonists was demonstrated in chorionic plate arteries in FGR pregnancy. Constriction to U46619 (thromboxane mimetic) and relaxation to sodium nitroprusside (nitric oxide donor) were significantly increased in the arteries of FGR pregnancies compared with normal pregnancies. No relationship existed between Doppler indices and chorionic plate responses in normal or FGR pregnancies.

Conclusions  Fetoplacental vascular reactivity is altered in FGR pregnancy independently of UA Doppler waveform indices. Altered function may be additive to the pathophysiology underlying abnormal Doppler waveforms and could contribute to the inappropriate control of vascular tone in FGR.
The effect of exercise on large artery haemodynamics in healthy young men
Authors: Sharman J. E. , McEniery C. M. , Campbell R. I. , Coombes J. S. , Wilkinson I. B. , Cockcroft J. R.
Published: November 2005

Background  Brachial blood pressure predicts cardiovascular outcome at rest and during exercise. However, because of pulse pressure amplification, there is a marked difference between brachial pressure and central (aortic) pressure. Although central pressure is likely to have greater clinical importance, very little data exist regarding the central haemodynamic response to exercise. The aim of the present study was to determine the central and peripheral haemodynamic response to incremental aerobic exercise.

Materials and methods  Twelve healthy men aged 31 ± 1 years (mean ± SEM) exercised at 50%, 60%, 70% and 80% of their maximal heart rate (HRmax) on a bicycle ergometer. Central blood pressure and estimated aortic pulse wave velocity, assessed by timing of the reflected wave (TR), were obtained noninvasively using pulse wave analysis. Pulse pressure amplification was defined as the ratio of peripheral to central pulse pressure and, to assess the influence of wave reflection on amplification, the ratio of peripheral pulse pressure to nonaugmented central pulse pressure (PPP : CDBP‐P1) was also calculated.

Results  During exercise, there was a significant, intensity‐related, increase in mean arterial pressure and heart rate (P < 0·001). There was also a significant increase in pulse pressure amplification and in PPP : CDBP‐P1 (P < 0·001), but both were independent of exercise intensity. Estimated aortic pulse wave velocity increased during exercise (P < 0·001), indicating increased aortic stiffness. There was also a positive association between aortic pulse wave velocity and mean arterial pressure (r = 0·54; P < 0·001).

Conclusions  Exercise significantly increases pulse pressure amplification and estimated aortic stiffness.
Modulatory effect of mannose‐binding lectin on cytokine responses: possible roles in HIV infection
Authors: Heggelund L. , Mollnes T. E. , Espevik T. , Müller F. , Kristiansen K. I. , Aukrust P. , Frøland S. S.
Published: November 2005

Background  Mannose‐binding lectin (MBL) is a soluble receptor of the innate immune system, probably contributing to antimicrobial defence. The possible role of MBL in HIV infection is unclear.

Materials and methods  Peripheral blood mononuclear cells (PBMCs) from 28 HIV‐infected patients and 13 healthy controls were stimulated with MBL and costimulated with HIV‐1 gp120 or mannan from Saccharomyces cerevisiae before inflammatory responses in PBMC cultures were examined by enzyme‐linked immunosorbent assay (ELISA) and flow cytometry. HIV‐1 RNA replication in vitro was assessed by quantitative reverse transcription polymerase chain reaction (RT‐PCR) in supernatants from patients with measurable HIV‐1 RNA levels.

Results  (i) Enhanced TNF‐α responses were observed when PBMCs from healthy controls and HIV‐infected patients were stimulated with MBL and costimulated with HIV‐1 gp120 or mannan. (ii) MBL stimulation induced increased HIV RNA replication in culture supernatants when costimulated with mannan.

Conclusions  The present study suggests a modulatory role of MBL on cytokine responses, and HIV replication after stimulation with microbial products. These effects of MBL on inflammatory responses and viral replication may be clinically relevant for HIV infection.
Haem oxygenase‐1 genotype and cardiovascular adverse events in patients with peripheral artery disease
Authors: Dick P. , Schillinger M. , Minar E. , Mlekusch W. , Amighi J. , Sabeti S. , Schlager O. , Raith M. , Endler G. , Mannhalter C. , Wagner O. , Exner M.
Published: November 2005

Background  A functional GT dinucleotide length polymorphism in the haem oxygenase‐1 (HO‐1) gene promoter is thought to be involved in the pathogenesis of cardiovascular disease. Short (< 25) (GT)n repeats are suggested to facilitate enhanced HO‐1 up‐regulation in response to injury and confer potent anti‐inflammatory and antioxidative effects.

Materials and methods  We investigated the association between the HO‐1 GT‐polymorphism and cardiovascular outcome in 472 patients with advanced peripheral artery disease. Cardiovascular risk profile and DNA samples for determination of the HO‐1 genotype (carrier vs. noncarrier of a short (GT)n repeat allele) were obtained at baseline, and patients were followed for median 21 months for the occurrence of coronary events (myocardial infarction, percutaneous coronary interventions and coronary artery bypass graft), cerebrovascular events (stroke or carotid revascularization) and all‐cause mortality.

Results  Coronary events occurred in 48 patients (9%), cerebrovascular events in 40 patients (9%) and 59 patients (13%) died. In total, 173 major adverse cardiovascular events (MACE) occurred in 133 patients (28%). Carriers of the short (GT)n repeat allele had a 0·46‐fold reduced adjusted hazard ratio for coronary events (P = 0·016) as compared to noncarriers. No significant difference was found for cerebrovascular events, mortality and overall MACE.

Conclusion  Apparently, the HO‐1 genotype exerts potentially protective effects against coronary adverse events in patients with peripheral artery disease. Homozygous and heterozygous carriers of < 25 (GT)n repeats had lower rates of myocardial infarction, percutaneous coronary interventions and coronary bypass operations compared to patients with longer (GT)n repeats.
Modelling the effect of soil water content and sorption on dye‐tracer fluorescence
Authors: Bänninger D. , Lehmann P. , Flühler H. , Guglielmetti M.
Published: November 2005

Fluorescent dye tracers are used to show concentration maps of tracer fronts, plumes and pathways on soil profiles and in monolith cross sections. The physical process of fluorescence from the exposed soil surfaces must be understood in order to retrieve accurately the concentration of such compounds. We found in a laboratory experiment that the fluorescence of quartz sand stained with Acid Yellow depends both on the tracer concentration and the soil water content. In this study, we investigate the dependence of fluorescence on the water content by using a radiative transfer model. The hypothesis of our modelling approach is that fluorescence depends on water content (1) because of the adsorption properties of the tracer and (2) because the microscopic distribution of the water phase changes the positioning and emission of the excited fluorescence molecules in the sample. Our model results show that both factors influence fluorescence to a similar extent, as observed in the Acid Yellow experiment. Because these results explain only part of the overall variation in the experiment, further factors, in addition to the postulated causes, have to be considered for determining concentration maps of fluorescent tracers from real soil profiles.
The Skaergaard intrusion: from icon to precious metal deposit
Authors: Brooks Kent
Published: November 2005

Ever since Wager and Deer's classic memoir in 1939 the Skaergaard intrusion has been (or should have been) a central part of every student's education in igneous petrology. Seventy years after the initial fieldwork it is still a major target for academic research, seeking to understand the processes of magmatic diversification. Consequently, a huge literature has accumulated on the subject. Recently, attention has turned to the Skaergaard as a precious metal exploration target.
Effects of experimental drought on soil respiration and radiocarbon efflux from a temperate forest soil
Authors: BORKEN WERNER , SAVAGE KATHLEEN , DAVIDSON ERIC A. , TRUMBORE SUSAN E.
Published: November 2005

Soil moisture affects microbial decay of SOM and rhizosphere respiration (RR) in temperate forest soils, but isolating the response of soil respiration (SR) to summer drought and subsequent wetting is difficult because moisture changes are often confounded with temperature variation. We distinguished between temperature and moisture effects by simulation of prolonged soil droughts in a mixed deciduous forest at the Harvard Forest, Massachusetts. Roofs constructed over triplicate 5 × 5 m2plots excluded throughfall water during the summers of 2001 (168 mm) and 2002 (344 mm), while adjacent control plots received ambient throughfall and the same natural temperature regime. In 2003, throughfall was not excluded to assess the response of SR under natural weather conditions after two prolonged summer droughts. Throughfall exclusion significantly decreased mean SR rate by 53 mg C m−2 h−1over 84 days in 2001, and by 68 mg C m−2 h−1over 126 days in 2002, representing 10–30% of annual SR in this forest and 35–75% of annual net ecosystem exchange (NEE) of C. The differences in SR were best explained by differences in gravimetric water content in the Oi horizon (r2=0.69) and the Oe/Oa horizon (r2=0.60). Volumetric water content of the A horizon was not significantly affected by throughfall exclusion. The radiocarbon signature of soil CO2efflux and of CO2respired during incubations of O horizon, A horizon and living roots allowed partitioning of SR into contributions from young C substrate (including RR) and from decomposition of older SOM. RR (root respiration and microbial respiration of young substrates in the rhizosphere) made up 43–71% of the total C respired in the control plots and 41–80% in the exclusion plots, and tended to increase with drought. An exception to this trend was an interesting increase in CO2efflux of radiocarbon‐rich substrates during a period of abundant growth of mushrooms.

Our results suggest that prolonged summer droughts decrease primarily heterotrophic respiration in the O horizon, which could cause increases in the storage of soil organic carbon in this forest. However, the C stored during two summers of simulated drought was only partly released as increased respiration during the following summer of natural throughfall. We do not know if this soil C sink during drought is transient or long lasting. In any case, differential decomposition of the O horizon caused by interannual variation of precipitation probably contributes significantly to observed interannual variation of NEE in temperate forests.
IS15  Developing vaccines in the era of genomics and toll receptors
Authors: Rappuoli R.
Published: November 2005

Vaccination is considered the most effective medical intervention. In the last century it eliminated or eradicated most of the infectious diseases responsible for much of human morbidity and mortality during recorded history. Most of the vaccines have been developed following the principles set by Pasteur to isolate, inactivate and inject the microorganism causing disease. While these technologies have been very successful in the past and will continue to dominate the short term future of vaccination, the progress in the understanding of the immune system and the availability of the genetic code of microorganisms provide new opportunities allowing to develop vaccines against diseases that have been difficult to tackle following Pasteur's principles. Today novel vaccines can be designed from the genome of microorganisms (reverse vaccinology) and can be made more potent by using novel adjuvants and immunostimulatory molecules targeting the innate immune system. In general, novel vaccines also have an excellent safety profile. The possibility to manipulate the immune system by powerful immunostimulatory molecules also opens the way to tackle by therapeutic vaccination chronic infectious diseases like HCV, HIV and cancer.
The effect of addition of calcium and processing temperature on the quality of guava in syrup
Authors: Sato Ana Carla K. , Sanjinéz‐Argandoña Eliana J. , Cunha Rosiane L.
Published: November 2005

The effect of process temperature and calcium concentration in the cooking syrup of guava in syrup were studied. A central composite rotatable design (CCRD) was used to optimize the quality indices of the final product, such as texture and colour. All of the processed guava quality parameters were compared with those of the fresh fruit and of a commercial sample to evaluate the effects of processing on the final product quality. Increase in the process temperature promoted changes in the final product colour, the fruit becoming darker. On the contrary, higher calcium concentrations in the cooking syrup produced lighter samples, with colour parameters closer to those of the fresh fruit. In general, the addition of calcium promoted better texture and minimized the negative effects of temperature on the mechanical properties. Processed guavas had higher rupture stress and strain than fresh fruit, indicating an increase in hardness and elasticity.
Wildfire effects on plant species richness at multiple spatial scales in forest communities of the southern Appalachians
Authors: REILLY MATTHEW J. , WIMBERLY MICHAEL C. , NEWELL CLAIRE L.
Published: November 2005

We fitted species‐area curves to the power function and examined changes in the parameters to quantify changes in species richness of all plants together, trees only and non‐trees over five scales of magnitude (0.01 m2 to 400 m2) after a wildfire in the Linville Gorge Wilderness Area, North Carolina, USA.

Increases in species richness of all plants together occurred after the fire at all scales and increased in magnitude as scale increased. However, a lack of change in the slopes (z‐values) of species‐area curves indicates that proportional changes were independent of scale of observation below 400 m2. Changes in species richness were predominantly driven by immigration, which was significantly related to fire severity. Survival of species present pre‐fire was greater than local extinction, but neither was related to severity.

Species richness of trees increased at all scales but proportional increases were smaller at larger scales and slopes of species‐area curves decreased after the fire. Local seedling recruitment increased species richness at small scales, but low rates of immigration due to dispersal limitation in most species limited increases at larger scales.

Directional changes in species richness of non‐trees were not always consistent at fine scales but both absolute and relative changes were positive at scales ≥ 1 m2 and increased with increasing scale. Slopes of species‐area curves increased post‐fire because localized patterns of immigration within plots resulted in little mixing of species at small scales but large changes in species richness at larger scales.

Fire in the southern Appalachians increases plant species richness within local communities, but rates of species turnover and patterns of beta diversity are maintained by local recruitment of tree seedlings at small scales and immigration of herb, shrub and vine species at larger scales.

Although decreased levels of competition after disturbance promote species coexistence at small scales, changes in species richness at larger scales are determined by the degree that the local community is linked to the species pool of the surrounding landscape through processes related to dispersal, particularly mass effects.
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

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

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

Spatial 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

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

Rationale  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

Rationale  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

Rationale  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

Rationale, 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

Rationale 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

Purpose  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.