bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of the spatial distribution of winter seed food resources on their use by farmland birds
Authors: SIRIWARDENA GAVIN M. , CALBRADE NEIL A. , VICKERY JULIET A. , SUTHERLAND WILLIAM J. 
Published: May 2006

Summary

Agri‐environment measures providing winter seed are central to current management activities aiming to reverse granivorous farmland bird declines. Previous research has considered the effectiveness of particular agri‐environment options, but the influence of their distribution in the landscape, an important factor in determining cost‐effectiveness, has received less attention. We used a large‐scale field experiment in eastern England, featuring 10 replicates of a spatial arrangement of seven artificial feeding stations separated by different distances, to investigate bird movements between discrete winter food resources.
Feeding sites were established and bird use monitored at least weekly over two winters (November–March). Habitat type in the areas surrounding the feeding sites was also recorded. Two measures of feeding site use were analysed as functions of the distance from the nearest alternative feeding site, controlling for ambient resource availability, for 11 passerines (including chaffinch Fringilla coelebs, reed bunting Emberiza schoeniclus and yellowhammer Emberiza citrinella and non‐granivores such as blue tit Parus caeruleus).
Feeding site use varied significantly with separation distance for nine species. For most, both maximum counts and bird minutes were higher at more isolated sites, but the opposite was true for yellowhammer and reed bunting. Most relationships incorporated significant thresholds at separations of around 500 m, with low site use below the threshold and high above it (or vice versa).
The results suggested that species such as chaffinch and blue tit made disproportionately more use of food at isolated sites than at clumped ones, but that reed buntings and yellowhammers used food in proportion to its availability, moving freely between more clumped patches. In both cases, birds tended to share resources separated by 500 m or less. At greater separations, resources tended to be used by discrete groups of birds. Radio‐tracking and colour‐ringing work produced corroborative evidence.
Synthesis and applications. The response of birds to the experimental food resource distribution implies that creating resource patches more than 1 km apart should be most cost‐effective, a recommendation that can inform agri‐environment scheme planning directly. This distance may represent a minimum, however, because birds might locate standing crops more readily than inconspicuous artificial food patches.
Prevalence of monodominant vigorous tree populations in the tropics: herbivory pressure on Tabebuia species in very different habitats
Authors: RIBEIRO SÉRVIO P. , BROWN VALERIE K. 
Published: May 2006

Summary

We have studied the reproductive performance, early establishment and insect herbivory in two Tabebuia species found in contrasting distant habitats. Tabebuia ochracea and T. aurea are sympatric in the cerrado (Brazilian savanna), whereas T. aurea also colonizes floodplains in the wetlands of the ‘Pantanal Matogrossense’ as large monodominant stands, but is sparsely distributed in the cerrado.
We test the hypothesis that T. aurea has a more vigorous genotype in the Pantanal than in the cerrado, which may be due to a lower negative selection caused by insect herbivory, positive selection for better soil conditions and an increased growth in the face of stochastic flooding. In addition, we predict that T. ochracea is better adapted to withstand higher herbivory rates than T. aurea, and is thus more successful in the cerrado.
Kruskal–Wallis analysis and Wilcoxon paired‐sample tests were used to compare adult tree reproductive traits. A reciprocal transplant experiment, combined with a glasshouse experiment, was used to investigate herbivory on half‐sib seed families found in each habitat.
Over a 2‐year period, T. ochracea had the higher investment in flower and seed production, which compensated for lower germination rates. However, in the Pantanal, T. aurea had the greatest conversion of flowers to fruit.
Fewer seeds of T. aurea survived and germinated in the cerrado than in the Pantanal, but seedlings from the Pantanal grew faster than those from the cerrado. The growth rate of T. ochracea was approximately four times lower than that of T. aurea.
Herbivory on seedlings was lower in the Pantanal than in the cerrado. Although seedlings of T. aurea from the Pantanal suffered the highest rates of herbivory in the cerrado, they survived equally to seedling genotypes from the cerrado. Tabebuia aurea had a higher mortality in both the cerrado and under controlled environmental conditions.
Faster growth rates may evolve when favourable abiotic conditions prevail. Although herbivores may promote habitat specialization by restricting colonization of poor soil environments by fast‐growing species, herbivory pressure may select for tree genotypes with conservative growth rates in newly colonized habitats with poor soil conditions and intense herbivory.
Abrupt population changes in treeline ecotones along smooth gradients
Authors: WIEGAND THORSTEN , CAMARERO J. JULIO , RÜGER NADJA , GUTIÉRREZ EMILIA 
Published: May 2006

Summary
We developed a spatially explicit and individual‐based simulation model describing the dynamics of tree populations across treeline ecotones. Our aims were to identify minimal factors and processes able to generate treeline types with abrupt vs. smooth transitions in different variables (tree height, age, density), to investigate the role of positive feedback in pattern generation, and to determine why krummholz appears at some but not all treelines. We hypothesized that a different balance between smooth growth and mortality gradients across the treeline ecotone could account for differences between commonly observed treeline types.
The model contained only processes and factors regarded as essential for producing a treeline ecotone and was parameterized with an extensive, individual‐based data set from Pinus uncinata treelines in the Spanish Pyrenees. However, parameters expected to influence treeline type were systematically varied.
The simple model was able to generate major treeline types differing in abruptness and krummholz abundance. The most important factors determining treeline types were the relative strength of growth and mortality gradients, followed by facilitation strength, whereas demographic parameters accounted for more subtle differences.
Only certain combinations of growth inhibition, mortality and facilitation allowed for the emergence of certain treeline types characterized by contrasting abruptness values and the presence or absence of krummholz. High krummholz densities emerged only under positive feedback and strongly increasing growth inhibition across the ecotone. Abruptness in adult tree density was positively correlated with facilitation strength and growth inhibition. By contrast, treelines with abrupt height transitions occurred only where both low growth inhibition and a strongly increasing mortality occurred across the ecotone.
Our analysis suggests that treeline features are not arbitrary but that there is a clear signal in the pattern which allows for inference of the underlying processes. Our approach of a systematic comparison of model predictions and various observed patterns can be widely applied for testing hypotheses on the functioning of ecological systems and for deriving specific questions for further investigations in the field.
Plant mass–density relationship along a moisture gradient in north‐west China
Authors: DENG JIAN‐MING , WANG GEN‐XUAN , MORRIS E. CHARLES , WEI XIAO‐PING , LI DONG‐XIU , CHEN BAO‐MING , ZHAO CHANG‐MING , LIU JING , WANG YUN 
Published: May 2006

Summary

Metabolic scaling theory predicts that the rate of resource use per unit area is independent of the average mass per individual and that the slope of the log mass–log density relationship should be −4/3.
Data were obtained from plant communities along a natural gradient of moisture and latitude in north‐west China to test the generality of this theory.
The allometric exponents (slopes of the log mass–log density relationship) for above‐ground biomass decreased with natural moisture levels and plant cover, deviating from the predictions of the energy equivalence theory. Allometric exponents for below‐ground and total biomass were similar among the three sites and were much closer to the predicted value of −4/3.
Metabolic scaling theory may be applicable under many growth conditions, but not when restricted to above‐ground biomass under drought stress. The rate of supply of the limiting resource per unit area determines which plant parts behave according to theory.
The effects of plant diversity and insect herbivory on performance of individual plant species in experimental grassland
Authors: SCHERBER CHRISTOPH , MILCU ALEXANDRU , PARTSCH STEPHAN , SCHEU STEFAN , WEISSER WOLFGANG W. 
Published: May 2006

SummaryThere is increasing evidence that components of biodiversity affect processes at the ecosystem level; yet, the effects of biodiversity on the performance of individual organisms or particular trophic interactions are largely unexplored.We transplanted 10 individuals ofRumex acetosainto 82 experimental grassland plots differing in plant species and functional group richness. Half of the plants received an insecticide treatment to manipulate insect herbivory.We measured the amount of herbivory, plant size, survival and reproductive parameters in 2003 and 2004.Insect herbivores removed on average 4.3% (2003) and 5.1% (2004) of leaf area in unsprayed plants. Spraying significantly reduced damage levels on average by approximately 50%. Herbivory significantly decreased plant weight, leaf size and number, and inflorescence length and size.Plant height and inflorescence size ofR. acetosasignificantly decreased with an increase in species diversity. Mortality was slightly higher in the species‐poor mixtures. Plant functional group diversity had little effect on plant performance. The presence of legumes generally increased, while the presence of grasses generally decreased, morphological parameters and fitness inR. acetosa.Overall, the presence of particular plant functional groups was more important than functional group or species richnessper se, and insect herbivores had additive effects of the same magnitude as the presence of particular plant functional groups.Insect herbivory and plant functional identity, rather than species richness, determine the performance of individual plant species in temperate grasslands.
Chloroplast DNA phylogeography of European ashes,Fraxinussp. (Oleaceae): roles of hybridization and life history traits
Authors: HEUERTZ M. , CARNEVALE S. , FINESCHI S. , SEBASTIANI F. , HAUSMAN J. F. , PAULE L. , VENDRAMIN G. G. 
Published: May 2006

AbstractWe investigated range‐wide phylogeographic variation in three European ash species (Fraxinussp., Oleaceae). Chloroplast DNA (cpDNA) microsatellites were typed in the thermophilousFraxinus angustifoliaandFraxinus ornusand the observed haplotypes and the geographic distribution of diversity were compared to cpDNA data previously obtained in the more cold‐tolerantFraxinus excelsior. We found wide‐ranging haplotype sharing between the phylogenetically closeF. angustifoliaandF. excelsior, suggesting hybridization (i) in common glacial refuges in the Iberian Peninsula, northern Italy, the eastern and/or Dinaric Alps and the Balkan Peninsula, and/or (ii) during postglacial recolonization. The data allowed us to propose additional glacial refuges forF. angustifoliain southern Italy and in Turkey, and populations from the latter region were particularly polymorphic. There was evidence for refuge areas in Italy, the Balkan Peninsula and Turkey forF. ornus, which did not share any single chloroplast haplotype with the other species. In bothF. angustifoliaandF. ornus, cpDNA diversity (hS = 0.027 andhS = 0.009, respectively) was lower and fixation levels (GST = 0.964 andGST = 0.983, respectively) higher than in sympatricF. excelsior(hS = 0.096,GST = 0.870). These diversity patterns could be due to temperature tolerance or the demographic history.
Cutaneous presentation on the eyelid of primary, systemic, CD30+, anaplastic lymphoma kinase (ALK)‐negative, anaplastic large‐cell lymphoma (ALCL)
Authors: Mencía‐Gutiérrez Enrique , Gutiérrez‐Díaz Esperanza , Salamanca Javier , Martínez‐González Miguel A. 
Published: May 2006

AbstractAim  To report an unusual case of cutaneous presentation on the eyelid of systemic (or nodal), CD30+, anaplastic large‐cell lymphoma (ALCL).Methods  A 39‐year‐old man presented with a rapidly growing exophytic mass on the left upper eyelid, with a protuberant, ulcerated aspect and with discharge. The patient showed lymph node involvement 3 months after the appearance of the lesion on the eyelid (the lesion itself appeared 1 week before examination).Results  The histopathologic and immunohistochemical diagnosis was ALCL, T‐cell phenotype, strongly positive for CD43 and CD30, and negative for CD3, anaplastic lymphoma kinase (ALK), and B‐cell antigens. Treatment was by radiotherapy and, later, chemotherapy (cyclophosphamide, adriamycin, vincristine, and prednisolone, CHOP) for skin recurrences and lymphadenopathies over 5 years. There has been no recurrence for more than 6 years.Conclusions  Primary, systemic, CD30+, ALK‐negative, ALCL presentations generally have a poor prognosis and tend to occur in older individuals, although the clinical outcome is highly variable and difficult to predict in individual cases. Only three cases of ALCL have been described in the ocular adnexae and none was ALK‐negative.
Quinine sulfate inhibits invasion of some bacterial skin pathogens
Authors: Wolf Ronni , Tufano Maria Antonietta , Ruocco Vincenzo , Grimaldi Elena , Ruocco Eleonora , Donnarumma Giovanna , Baroni Adone 
Published: May 2006

AbstractBackground  As some of the many patients who receive antimalarials for the treatment of noninfective inflammatory diseases (lupus erythematosus, collagen vascular diseases, rheumatoid arthritis, and others) are also immunosuppressed because of their disease and/or treatments, and may have concomitant bacterial infections, we investigated the effect of these drugs on the growth and invasion of several bacteria that are commonly associated with skin and soft tissue infections to determine whether they could protect against such conditions and obviate the need for an additional antibiotic drug.Methods  The effect of quinine sulfate (QS) at concentrations of 50 and 100 µm on the entry process of Enterobacter agglomerans, Staphylococcus aureus, Pseudomonas aeruginosa, and Klebsiella pneumoniae into Caco‐2 cells was studied during the infection period. The invasive efficiency was expressed as the number of viable internalized bacteria obtained by counting the colony‐forming units (CFUs).Results  The invasive ability of E. agglomerans and S. aureus was significantly inhibited by 50 and 100 µm QS in a dose‐dependent manner when the drug was added to Caco‐2 cell monolayers during the infection period; however, QS had no significant effect on the internalization of P. aeruginosa or K. pneumoniae.Discussion and conclusions  Antimalarial drugs are currently widely used to treat patients with autoimmune dermatologic and rheumatologic diseases, and have also been recently proposed as additional therapy for patients with human immunodeficiency virus (HIV) infection. These patients, who are often immunocompromised, may receive a secondary advantage from these antimalarials, which may provide some protection against staphylococci (amongst the most important human pathogens causing many superficial and systemic infections) and E. agglomerans.
Effect of indomethacin and selective cyclooxygenase‐2 inhibitors on proteinuria and renal function in patients with AA type renal amyloidosis
Authors: KAHVECIOGLU SERDAR , DILEK KAMIL , AKDAG IBRAHIM , GULLULU MUSTAFA , DEMIRCAN CELALETTIN , ERSOY ALPASLAN , YURTKURAN MUSTAFA 
Published: May 2006

SUMMARY:Aims:  Because the cardiovascular system (CVS) side‐effects of cyclooxygenase‐2 (COX‐2) selective inhibitors have recently been questioned, we aimed to compare the renal and haemodynamic effects of cyclooxygenase selective (celecoxib and rofecoxib) and non‐selective non‐steroidal anti‐inflammatory drugs (NSAIDs) (indomethacin) in patients with renal amyloidosis secondary to rheumatological diseases who required anti‐inflammatory agents and are taking maximum tolerable dose of angiotensin‐converting enzyme inhibitors.Methods:  The present study was performed on 11 patients with stable proteinuria who were diagnosed as AA amyloidosis secondary to rheumatological diseases confirmed by renal biopsies. The study had three consecutive stages (celecoxib 200 mg/day; indomethacin 100 mg/day; rofecoxib 25 mg/day.) Each was given for 4 weeks and a wash‐out phase of 3 weeks was allowed between consecutive stages.Results:  Although the decrease of proteinuria in the celecoxib period was higher than in the rofecoxib and indomethacin periods, the difference was not statistically significant. No statistically significant differences were found between serum urea, creatinine, creatinine clearance and urinary sodium excretion.Conclusion:  In this study, no differences were found between indomethacin and the two selective COX‐2 inhibitors in respect to proteinuria and renal functions in 11 patients with renal amyloidosis secondary to rheumatological diseases with varying degrees of proteinuria. Routine doses of NSAIDs brought no additional benefit to the ACE inhibitor use in terms of proteinuria and renal functions. The use of selective COX‐2 inhibitors should be limited to their anti‐inflammatory and analgesic effects in this population.
Macrophage accumulation in human progressive diabetic nephropathy
Authors: NGUYEN DUY , PING FU , MU WEI , HILL PRUDENCE , ATKINS ROBERT C , CHADBAN STEVEN J 
Published: May 2006

SUMMARY:Background:  Diabetic nephropathy is a major global health problem. Progression to renal failure is common; however, the mechanisms are unknown. Experimental models suggest a role for macrophages. Therefore, macrophage accumulation and its relationship to the subsequent clinical course were studied.Methods:  A retrospective study of baseline histology and the subsequent clinical course over at least 5 years involving 20 consecutive patients with a histological and clinical diagnosis of diabetic nephropathy was performed. The relationship between macrophage accumulation in renal biopsy tissue (KP‐1/anti‐CD68+ cells), baseline measures of known predictors of progression (proteinuria, tubulointerstitial damage, myofibroblast accumulation) and progression over 5 years (plot of reciprocal of serum creatinine) was quantified.Results:  Accumulation of macrophages was apparent in the glomeruli (2.8 + 0.7/gcs vs 1.0 + 0.2 for normals, P = not significant) and interstitium (296.9 + 63.3/mm2vs 19.0 + 1.3/mm2 for normals, P = 0.002) of patients with diabetic nephropathy. Glomerular macrophage number correlated with baseline serum creatinine (r = 0.548, P = 0.012) but not with progression of renal failure as glomerular macrophages were prevalent in early, but not advanced diabetic nephropathy. Interstitial macrophage accumulation correlated strongly with serum creatinine (r = 0.649, P = 0.002), proteinuria (r = 0.779, P < 0.0001), interstitial fibrosis (r = 0.774, P < 0.0001) and inversely with the slope of 1/serum creatinine (r = −0.531, P = 0.023).Conclusion:  Macrophages accumulate within glomeruli and the interstitium in diabetic nephropathy and the intensity of the interstitial infiltrate is proportional to the rate of subsequent decline in renal function. These human data support animal studies that suggest a pathogenic role for the macrophage in diabetic nephropathy.
The evolution of virulence and host specialization in malaria parasites of primates
Authors: Garamszegi László Zsolt 
Published: May 2006

AbstractParasite virulence, i.e. the damage done to the host, may be a by‐product of the parasite's effort to maximize its fitness. Accordingly, several life‐history trade‐offs may explain interspecific differences in virulence, but such constraints remain little tested in an evolutionary context. In this phylogenetic study of primate malarias, I investigated the relationship between virulence and other parasite life‐history traits. I used peak parasitaemia as a proxy for virulence, because it reflected parasite reproductive success and parasite‐induced mortality. Peak parasitaemia was higher in specialist than in generalist species, even when confounding life‐history traits were controlled. While there was a significant phylogenetic relationship between the number of competitors per host and host specialization, peak parasitaemia was unrelated to within‐host competition. Therefore, the key evolutionary factor that favours virulence is host specialization, and the evolutionary success of virulent parasites, such as Plasmodium falciparum, may be better understood when the trade‐off in virulence between different hosts is considered. Such phylogenetic results may help us design better protection programmes against malaria.
The leader sequence triggers and enhances several functions of clusterin and is instrumental in the progression of human prostate cancer in vivo and in vitro
Authors: ZHANG QIANG , ZHOU WEI , KUNDU SHILAJIT , JANG THOMAS L. , YANG XIMING , PINS MICHAEL , SMITH NORM , JOVANOVIC BORKO , XIN DIANQI , LIANG LILI , GUO YINGLU , LEE CHUNG 
Published: May 2006

OBJECTIVETo investigate the role of the leader sequence (which during clusterin biosynthesis facilitates its proper post‐translational processing and secretion) in the functional activities of clusterin, a ubiquitous secretory glycoprotein with many biological functions, reported to be pro‐apoptotic and anti‐apoptotic in target cells, but for which the dual mechanism remains unclear.MATERIALS AND METHODSWe designed an expression vector starting from the second in‐frame ATG on the full‐length human clusterin cDNA that was capable of driving the expression of both the full‐length and the truncated isoforms of clusterin. We established stable expression clones of the androgen‐dependent prostate cancer line LNCaP expressing clusterin with and without the leader sequence. This induced expression provided an opportunity to evaluate both the in vivo and in vitro actions of clusterin expression.RESULTSThe LNCaP cells expressing clusterin with the leader sequence resisted apoptosis induced by tumour necrosis factor (TNF)‐α, but clones with no leader sequence were highly susceptible to TNF‐α‐induced apoptosis. Furthermore, in the absence of the leader sequence, the expressed clusterin had a molecular weight consistent with that of the predicted holoprotein (40 kDa), suggesting a compromised post‐translational processing with diffuse distribution throughout the cytoplasm. However, cells transfected with the full‐length vector expressed clusterin of 60 and 35 kDa variants, and located exclusively in the Golgi apparatus. In vivo, only the overexpression of the full‐length clusterin is anti‐apoptotic and stimulates the proliferation of tumour.CONCLUSIONThe leader sequence is important in determining the functions of clusterin, which include anti‐apoptotic and anti‐necrotic properties. The lack of the leader sequence allowed the incompletely processed clusterin to induce apoptosis in target cells; without the leader sequence, clusterin functions differently. Thus, the leader sequence is a trigger for many functions of clusterin in the progression of human prostate cancer cells.