bluuebunny/crossref_metadata_2025_split huggingface dataset:
Are dingoes a trophic regulator in arid Australia? A comparison of mammal communities on either side of the dingo fence
Authors: LETNIC MIKE , KOCH FREYA 
Published: September 2009

AbstractThe direct and indirect interactions that large mammalian carnivores have with other species can have far‐reaching effects on ecosystems. In recent years there has been growing interest in the role that Australia's largest terrestrial predator, the dingo, may have in structuring ecosystems. In this study we investigate the effect of dingo exclusion on mammal communities, by comparing mammal assemblages where dingoes were present and absent. The study was replicated at three locations spanning 300 km in the Strzelecki Desert. We hypothesized that larger species of mammal subject to direct interactions with dingoes should increase in abundance in the absence of dingoes while smaller species subject to predation by mesopredators should decrease in abundance because of increased mesopredator impact. There were stark differences in mammal assemblages on either side of the dingo fence and the effect of dingoes appeared to scale with body size. Kangaroos and red foxes were more abundant in the absence of dingoes while Rabbits and the Dusky Hopping‐mouse Notomys fuscus were less abundant where dingoes were absent, suggesting that they may benefit from lower red fox numbers in the presence of dingoes. Feral cats and dunnarts (Sminthopsis spp.) did not respond to dingo exclusion. Our study provides evidence that dingoes do structure mammal communities in arid Australia; however, dingo exclusion is also associated with a suite of land use factors, including sheep grazing and kangaroo harvesting that may also be expected to influence kangaroo and red fox populations. Maintaining or restoring populations of dingoes may be useful strategies to mitigate the impacts of mesopredators and overgrazing by herbivores.
Circadian variation in resource quality: leaf water content and its relevance to eastern grey kangaroo Macropus giganteus and common wombat Vombatus ursinus
Authors: JARMAN PETER J. , EVANS MURRAY C. 
Published: September 2009

AbstractGreen leaves of six grass species in temperate Australia showed considerable circadian variation (especially in summer) in water content, which peaked late in the night and fell from sunrise to an afternoon minimum. In summer, water content of a set of ‘wetter’ species (Axonopus affinis, Pennisetum clandestinum and Paspalum dilatatum) was consistently higher and varied less profoundly through the 24 h than that of a ‘drier’ set (Imperata cylindrica, Poa labillardieri and Themeda triandra). Hour‐to‐hour and day‐to‐day variation in leaf water content of P. dilatatum in summer partly but imperfectly reflected ambient temperature. Recognizing the risks for herbivores of visiting water sources, we considered leaf water content as a source of free water for leaf‐grazing herbivores, eastern grey kangaroos Macropus giganteus and common wombats Vombatus ursinus. Using known field metabolic rates, energy requirements and digestive efficiencies, we calculated these two species' free‐water intakes when satisfying their energy needs with these grasses but distributing their grazing in different schedules. Both species would obtain more free water by their observed foraging schedules than by random or daytime‐only schedules. We calculated that the measured grasses could satisfy the water requirements of wombats but not always those of kangaroos, who would need to drink when forage water content was less than about 70%. Water content of grass leaf could rise above and fall below this value within a day, creating some scope for kangaroos to manage their need to visit water by adjusting foraging schedules or choice of grass species. In future studies, circadian variation in leaf water content should be considered as a factor (together with their thermal physiology) driving herbivores' activity scheduling, and affecting their dietary selection.
Latitudinal trends in foliar oils of eucalypts: Environmental correlates and diversity of chrysomelid leaf‐beetles
Authors: STEINBAUER MARTIN J. 
Published: September 2009

AbstractEucalypts are characterized by their oleaginous foliage, yet no one has considered the universality of oil expression or its ecological associations and implications for biodiversity. Published literature on the oils of 66 eucalypts was combined with geographic distribution information contained in the Australian National Herbarium (ANHSIR) database to investigate continent‐scale changes in oil yield and composition. The exposure to fire and rainfall of each eucalypt was considered in reference to Walker's data on fire frequency and Australian Bureau of Meteorology 97‐year records of rainfall variability. Host collection records for 69 species of chrysomelid leaf‐beetle were collated from entomologists to consider patterns of association with a subset of 16 eucalypts. Eucalypts endemic to the seasonally arid, sub‐tropical to tropical climates of northern Australia have less oleaginous and aromatic leaves than species endemic to the mesic, temperate climates of the southern parts of the continent. Maximum oil yield and the concentrations of cineole and pinene were positively correlated with minimum fire interval but not with rainfall variability. Low oil contents in more northerly distributed species may facilitate persistence in highly fire‐prone habitats. There were no patterns in the diversity of chrysomelid leaf‐beetles with either the oil yield or the concentrations of 1,8‐cineole or α‐pinene in their hosts. When taken in consideration with the apparent strategy of eucalypts to tolerate insect herbivory, current evidence augurs against high concentrations of cineole or pinene acting alone as antibiotic plant secondary metabolites.
Diplochory in two Jatropha (Euphorbiaceae) species of the Monte Desert of Argentina
Authors: RICKERT ADRIANA A. , FRACCHIA SEBASTIÁN 
Published: September 2009

AbstractThe potential explosive seed dispersal under controlled conditions and the dispersal by ants in natural populations are compared between two diplochoric species: Jatropha hieronymi Kuntze and J. excisa Griseb. The seeds of J. hieronymi are more than eightfold heavier than J. excisa seeds, and were explosively dispersed considerably further distances, reaching a maximum of almost 18 m. The differences in explosive dispersal distances between the two species seem to depend on both carpel wall thickness of the fruit and aerodynamic shape of the seed. Seed removal by ants was positively correlated with the presence of the elaiosome and was higher for J. excisa (83.6%) than for J. hieronymi (31.6%). Seed size was the major factor affecting the removal by ants, as only large bodied ants were able to transport the large seeds of J. hieronymi. The larger size and the higher oleic acid content of the elaiosomes of J. hieronymi seeds had no influence on the observed removal rates by ants. In contrast, ants transported the J. hieronymi seeds further distances than J. excisa seeds. Jatropha hieronymi distances achieved by both dispersal modes are in the range of the furthest distances described for a diplochorous species. Finally, the possible advantages of this dispersal mode in arid zones are discussed.
Accumulation of reelin‐positive plaques is accompanied by a decline in basal forebrain projection neurons during normal aging
Authors: Madhusudan Amrita , Sidler Corinne , Knuesel Irene 
Published: September 2009

AbstractBesides its critical role during neurodevelopment, the extracellular glycoprotein reelin is also a pivotal regulator of adult synaptic function and plasticity, and altered reelin‐mediated signalling has been suggested to contribute to neuronal dysfunction associated with Alzheimer’s disease. We have recently discovered, in aged rodents and non‐human primates, a pronounced decline in reelin‐positive interneurons and concomitant accumulation of reelin in extracellular amyloid‐like deposits, both being associated with episodic‐like memory impairments. Here, we report that these age‐related neuropathological changes in hippocampus, entorhinal and piriform cortices of aged wild‐type mice are accompanied by abnormal axonal varicosities and altered expression profiles of calcium‐binding proteins in plaque‐dense areas, as well as a significant reduction in the number of parvalbumin‐positive γ‐aminobutyric acid (GABA)ergic projection neurons in basal forebrain areas, including medial septum (MS), ventral and horizontal diagonal Band of Broca (VDB/HDB) and substantia innominata (SI), compared with young subjects. In addition, a significant reduction in the number of choline acetyltransferase‐positive cholinergic projection neurons was evident in the HDB/SI area but not in the MS of aged compared with young wild‐type mice. No reelin‐deposits were found in these basal forebrain regions. Our findings suggest that the elevated reelin plaque load in the projection areas of afferent subcortical GABAergic and cholinergic neurons including hippocampus, entorhinal and piriform cortices affects the axonal integrity and survival of these neurons, potentially contributing to the cognitive impairments observed in aged wild‐type mice.
Visual recalibration of auditory spatial perception: two separate neural circuits for perceptual learning
Authors: Passamonti Claudia , Frissen Ilja , Làdavas Elisabetta 
Published: September 2009

AbstractA remarkable example of rapid perceptual learning is the visual recalibration of auditory spatial perception, which can result in either a bias (ventriloquism after‐effect) or an improvement (multisensory enhancement) in auditory localization. Here, we examine the possibility that these after‐effects might depend on two distinct neural pathways (geniculostriate vs. collicular–extrastriate). To this end, patients with a lesion of the striate cortex (hemianopic patients) or temporoparietal cortex (neglect patients) were asked to localize weak sounds, before and after a brief exposure to repetitive auditory–visual stimulation which was given either in the normal or in the affected field. Adaptation comprised spatially disparate (Experiment 1) or spatially coincident (Experiment 2) auditory–visual stimuli. After exposure to spatially disparate stimuli in the normal field, all patients exhibited the usual shifts toward the visual attractor, at each sound location. In contrast, when the same kind of adaptation was given in the affected field, a consistent shift was still evident in neglect patients but not in patients with hemianopia. After adaptation to spatially coincident stimuli, and regardless of the adaptation hemifield, all patients exhibited a significant improvement in auditory localization, which was largest for sounds presented at the adapted location. The findings suggest the presence of two distinct recalibration mechanisms. Adapting to spatially conflicting stimuli invokes a corrective mechanism implemented within the geniculostriate circuit, which tries to reduce the registered discrepancy. Adapting to spatially aligned inputs invokes a mechanism implemented along a collicular–extrastriate circuit, which tries to reduce the localization error.
GABAergic interneurons targeting dendrites of pyramidal cells in the CA1 area of the hippocampus
Authors: Klausberger Thomas 
Published: September 2009

AbstractThe dendrites of pyramidal cells are active compartments capable of independent computations, input/output transformation and synaptic plasticity. Pyramidal cells in the CA1 area of the hippocampus receive 92% of their GABAergic input onto dendrites. How does this GABAergic input participate in dendritic computations of pyramidal cells? One key to understanding their contribution to dendritic computation lies in the timing of GABAergic input in relation to excitatory transmission, back‐propagating action potentials, Ca2+ spikes and subthreshold membrane dynamics. The issue is further complicated by the fact that dendritic GABAergic inputs originate from numerous distinct sources operating with different molecular machineries and innervating different subcellular domains of pyramidal cell dendrites. The GABAergic input from distinct sources is likely to contribute differentially to dendritic computations. In this review, I describe four groups of GABAergic interneuron according to their expression of parvalbumin, cholecystokinin, axonal arborization density and long‐range projections. These four interneuron groups contain at least 12 distinct cell types, which innervate mainly or exclusively the dendrites of CA1 pyramidal cells. Furthermore, I summarize the different spike timing of distinct interneuron types during gamma, theta and ripple oscillations in vivo, and I discuss some of the open questions on how GABAergic input modulates dendritic operations in CA1 pyramidal cells.
Neural encoding of cocaine‐seeking behavior is coincident with phasic dopamine release in the accumbens core and shell
Authors: Owesson‐White Catarina A. , Ariansen Jennifer , Stuber Garret D. , Cleaveland Nathan A. , Cheer Joseph F. , Mark Wightman R. , Carelli Regina M. 
Published: September 2009

AbstractMesolimbic dopamine neurons projecting from the ventral tegmental area to the nucleus accumbens (NAc) are part of a complex circuit mediating cocaine‐directed behaviors. However, the precise role of rapid (subsecond) dopamine release within the primary subregions of the NAc (the core and shell) and its relationship to NAc cell firing during this behavior remain unknown. Here, using fast‐scan cyclic voltammetry in rats we report rapid dopamine signaling in both the core and shell; however, significant differences were observed in the timing of dopamine release events within seconds of the cocaine‐reinforced response during self‐administration sessions. Importantly, simultaneous voltammetric and electrophysiological recordings from the same electrode reveal that, at certain sites within both subregions, neurons exhibiting patterned activation were observed at locations where rapid dopamine release was present; the greater the strength of the neural signal the larger the dopamine release event. In addition, it was at those locations that electrically‐evoked stimulated release was greatest. No changes in dopamine were observed where nonphasic neurons were recorded. Thus, although differences are evident in dopamine release dynamics relative to cocaine‐reinforced responding within the core and shell, dopamine release is heterogeneous within each structure and varies as a function of precise neuronal targets during cocaine‐seeking behavior.
Glucosylglycerate: a secondary compatible solute common to marine cyanobacteria from nitrogen‐poor environments
Authors: Klähn Stephan , Steglich Claudia , Hess Wolfgang R. , Hagemann Martin 
Published: September 2009

SummaryThe synthesis and accumulation of compatible solutes represent an essential part of the salt acclimation strategy of microorganisms. Glucosylglycerol is considered to be the typical compatible solute among marine cyanobacteria. However, genes that encode enzymes for the synthesis of glucosylglycerol were not detected in the genome sequences of marine picoplanktonic Prochlorococcus strains. Instead, we noticed the presence of genes that putatively encode for glucosylglycerate (GGA) synthesis among Prochlorococcus and most other closely related marine picocyanobacteria. Recombinant proteins from Prochlorococcus marinus SS120 and Synechococcus sp. PCC 7002 exhibited glucosyl‐phosphoglycerate synthase (GpgS) activity, and GpgS is a key enzyme of GGA synthesis. GGA accumulation was found to be salt‐ as well as nitrogen‐regulated in the coastal strain Synechococcus sp. PCC 7002. Moreover, GGA was also detected in all picoplanktonic Prochlorococcus and Synechococcus strains harbouring gpgS genes, especially under N‐limiting conditions. These results suggest that marine picocyanobacteria acquired the capacity to synthesize the negatively charged compound GGA during their evolution. Our results establish GGA as the fifth most widespread compatible solute among cyanobacteria. Additionally, GGA appears to replace glutamate as an anion to counter monovalent cations in marine picocyanobacteria from N‐poor environments.
Initial management of prostate cancer: first year experience with the Norwegian National Prostate Cancer Registry
Authors: Hernes Eivor , Kyrdalen Anne , Kvåle Rune , Hem Einar , Klepp Olbjørn , Axcrona Karol , Fosså Sophie D. 
Published: September 2009

Study Type – Therapy (individual cohort)  Level of Evidence 2bOBJECTIVEImproving a country’s management of cancer patients requires continuous evaluation, and requires the availability of population‐based prognostic and therapeutic variables. We aimed to document the national diagnostic and therapeutic tasks in Norwegian patients with prostate cancer diagnosed in 2004, with the 2003 European Association of Urology (EAU) guidelines representing the background.PATIENTS AND METHODSThe Norwegian Prostate Cancer Registry (NoPCR) was established in 2004, and data collected during this first year were reviewed. The Tumour‐Node‐Metastasis group, prostate‐specific antigen (PSA) level and Gleason score were recorded as basic diagnostic variables, with the initial treatment. Patients with nonmetastatic T1‐T3 tumours were separated from those with advanced disease (T4 and/or N+ and/or M+). Patients with T1‐T3 tumours, aged ≤75 years, and in good health were candidates for curative local treatment (‘CurCands’) and were allocated to risk groups.RESULTSThe compliance rate to the NoPCR was 96%; 2693 (72%) of 3744 eligible patients had T1‐T3 tumours and 833 (22%) had advanced disease (not classifiable in 218, 6%). Of 1650 CurCands (low‐risk 500; intermediate‐risk 453; high‐risk 697), 62% had radical prostatectomy or radiotherapy with or without hormone therapy, with the remaining 23% and 10% managed by, respectively, hormone therapy only or observation (other/unknown treatment, 6%).Only 64% of CurCands in the combined intermediate/high‐risk group had local treatment. In the low‐risk group local treatment was used in 57% of the patients, mainly in men with T2 tumours. In intermediate‐ and high‐risk CurCands, PSA was the strongest factor determining the performance of curative treatment. Adjuvant radiotherapy after radical prostatectomy was used in four of 142 patients with tumour‐involved margins.CONCLUSIONIn 2004 the initial management of prostate cancer in Norway was largely in accordance with the 2003 EAU guidelines, though there was some evidence of ‘over‐treatment’ of low‐risk patients and ‘under‐treatment’ of intermediate‐ and high‐risk patients. Some improvement of data collection by the NoPCR is warranted. National prostate cancer registries can contribute to improving the medical care of these patients.
Synergistic potentiation of interferon activity with maitake mushroom d‐fraction on bladder cancer cells
Authors: Louie Brandon , Rajamahanty Srinivas , Won John , Choudhury Muhammad , Konno Sensuke 
Published: September 2009

OBJECTIVETo examine whether the combination of interferon (IFN)‐α and maitake mushroom D‐fraction (PDF), a bioactive mushroom extract, might potentiate the anticancer activity of IFN‐α in bladder cancer T24 cells in vitro.MATERIALS AND METHODSEffects of recombinant IFN‐α2b (0–50 000 IU/mL), PDF (0–700 µg/mL), or their combinations were assessed on T24 cell growth at 72 h. Cell cycle analysis and assays for double‐stranded DNA‐dependent protein kinase (DNA‐PK) were performed to explore possible antiproliferative mechanism of these agents.RESULTSIFN‐α2b was able to induce a significant (≈50%) growth reduction at 20 000 IU/mL, which further declined to ≈66% at 50 000 IU/mL. PDF had no effects up to 200 µg/mL, but there was an ≈20% and ≈53% growth reduction at 400 and 700 µg/mL, respectively. When the varying concentrations of IFN‐α2b and PDF were combined, 10 000 IU/mL of IFN‐α2b combined with 200 µg/mL of PDF resulted in an ≈75% growth reduction. This was accompanied by a G1 cell cycle arrest, shown by cell cycle analysis. Concurrently, DNA‐PK activity in IFN‐α2b/PDF‐treated cells was almost three‐fold higher than controls.CONCLUSIONSThe combination of IFN‐α2b (10 000 IU/mL) and PDF (200 µg/mL) reduced growth by ≈75% in T24 cells. This appears to be due to a synergistic potentiation of these two agents, inducing a G1 arrest with DNA‐PK activation. Therefore, the IFN‐α2b/PDF combination could trigger DNA‐PK activation that may act on the cell cycle to cease cancer cell growth.
Self‐reported history of overweight and its relationship to disordered eating in adolescent girls with Type 1 diabetes
Authors: Markowitz J. T. , Lowe M. R. , Volkening L. K. , Laffel L. M. B. 
Published: September 2009

AbstractAims  Increased body weight and disordered eating attitudes/behaviours are common in adolescent girls with Type 1 diabetes (T1D). Disordered eating increases risks for diabetes‐related complications. This study aimed to identify a rapid screening approach for disordered eating attitudes and behaviours in adolescent girls with T1D and to examine the relationship between disordered eating and body weight in this population.Methods  Ninety adolescent girls, aged 12–19 years, provided a self‐assessment of weight status. Participants also completed questionnaires to assess attitudes/behaviours toward food and eating, appetitive responsiveness to the food environment, disinhibition in eating and weight history.Results  Forty‐three per cent of participants reported a history of overweight. Compared with participants who reported never being overweight, those who reported ever being overweight were significantly older, scored significantly higher on all measures of disordered eating attitudes/behaviours (P ≤ 0.009) and were 4.8 times more likely to be currently overweight or obese (P < 0.001). Glycated haemoglobin (HbA1c) was similar between those who did and did not report ever being overweight.Conclusions  Because of the ill‐health effects of disordered eating and the higher rate of overweight in adolescent girls with T1D, effective screening tools are warranted. The single question ‘Have you ever been overweight?’ may be sufficient as a first question to screen for those at high risk for disordered eating attitudes/behaviours and to provide early intervention and prevention.
Two‐step Prediction and Image Deflection for Exact Head Tracking in Virtual Environments
Authors: Mazuryk Tomasz , Gervautz Michael 
Published: September 2009

AbstractTime lag and image jittering are the main reasons for destroying the feeling of reality in most virtual environments. They cause motion sickness because human beings are simply not used to unrealistically generated feedback. This paper proposes advanced software methods that greatly reduce these unwanted effects: a new improved two‐step prediction method for better head tracking, an image deflection technique to reduce remaining error and a new software configuration that allows the full use of available hardware capabilities. Our improved prediction technique reduces prediction error by 50% in comparison to standard methods. The image deflection allows to extend the prediction distance by 100% while keeping the error below a tolerable level.
Syntax Channelling and Other Issues affecting Innovation in the Graphical User Interface
Authors: King Mike 
Published: September 2009

AbstractDoes the modern commercial Graphical User Interface constrain the developer of graphics applications into certain interaction styles? This paper looks at the Microsoft Windows environment as an example, with particular reference to the question of interaction modes, screen real‐estate and visual appearance. The concept of syntax channelling is introduced to help analyse the problem of modality, and the question of button‐down versus button‐up dragging is debated in the context of a range of commercial applications, and possible consequences for upper limb disorder. A Windows application developed by the author involving the implementation of a variety of innovative interfacing techniques is presented.