bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hull fouling as an invasion vector: can simple models explain a complex problem?
Authors: Sylvester Francisco , Kalaci Odion , Leung Brian , Lacoursière‐Roussel Anaïs , Murray Cathryn Clarke , Choi Francis M. , Bravo Monica A. , Therriault Thomas W. , MacIsaac Hugh J. 
Published: February 2011

Summary 1. The most effective way to manage nonindigenous species and their impacts is to prevent their introduction via vector regulation. While ships’ ballast water is very well studied and this vector is actively managed, hull fouling has received far less attention and regulations are only now being considered despite its importance for introductions to coastal, marine systems. 2. We conducted comprehensive in situ sampling and video recording of hulls of 40 transoceanic vessels to assess propagule and colonization pressure in Vancouver and Halifax, dominant coastal ports in Canada. Concomitant sampling was conducted of harbour fouling communities to compare hull and port communities as part of a vector risk assessment. 3. Although this vector has been operational for a long time, hull and harbour communities were highly divergent, with mean Sørensen’s similarity values of 0·03 in Halifax and 0·01 in Vancouver, suggesting invasion risk is high. Propagule pressure (up to 600 000 ind. ship−1) and colonization pressure (up to 156 species ship−1) were high and varied significantly between ports, with Vancouver receiving much higher abundances and diversity of potential invaders. The higher risk of fouling introductions in Vancouver is consistent with historical patterns of successful hull fouling invasions. 4. The extent of hull fouling was modelled using ship history predictors. Propagule pressure increased with time spent in previous ports‐of‐call and time since last application of antifouling paint, whereas colonization pressure increased with time since last painting and with the number of regions visited by the ship. Both propagule and colonization pressure were negatively related to the time spent at sea and the latitude of ports visited. 5. Synthesis and applications. A major challenge for applied invasion ecology is the effective management of introduction vectors. We found that hull fouling has a strong potential for introduction of many species to coastal marine habitats and that management should be considered. Simple variables related to the vessels’ hull husbandry, voyage, and sailing patterns may be used to predict and manage hull fouling intensity. The results presented here should interest policy makers and environmental managers who seek to reduce invasion risk, and ship owners seeking to optimize fuel efficiency.
A genomically tractable and ecologically relevant model herbivore for a model plant: new insights into the mechanisms of insect–plant interactions and evolution
Authors: GIRON DAVID , HUGUET ELISABETH 
Published: February 2011

AbstractThe availability of model microbial pathogens and plants has been key to characterizing resistance and virulence pathways and to shedding light on the mechanisms of host–parasite interactions and co‐evolution (e.g. Allen et al. 2004, Science306, 1957–1960; Bergelson et al. 2001, Science292, 2281–2285). However, the absence of genetically tractable arthropod parasites of model plants has impeded so far our ability to gain better insights into the mechanisms, evolution and ecological consequences of plant–herbivore interactions. In this issue of Molecular Ecology, Whiteman et al. (2011) highlight fascinating features of a drosophilid fly, Scaptomyza flava, that feeds on the model plant Arabidopsis thaliana. They explore the potential of this system for studying insect–plant interactions with a clever mix of phenotypic and genetic experiments providing a comprehensive and persuasive argument for the validity of this model system. This study sets the ground for key developments in the unravelling of mechanisms involved in (i) plant–insect interactions and co‐evolution, and (ii) transition to herbivory in arthropods and evolution of endophagous lifestyles.
Population structure of mycobionts and photobionts of the widespread lichen Cetraria aculeata
Authors: FERNÁNDEZ‐MENDOZA F. , DOMASCHKE S. , GARCÍA M. A. , JORDAN P. , MARTÍN M. P. , PRINTZEN C. 
Published: February 2011

AbstractLichens are symbioses between fungi (mycobionts) and photoautotrophic green algae or cyanobacteria (photobionts). Many lichens occupy large distributional ranges covering several climatic zones. So far, little is known about the large‐scale phylogeography of lichen photobionts and their role in shaping the distributional ranges of lichens. We studied south polar, temperate and north polar populations of the widely distributed fruticose lichen Cetraria aculeata. Based on the DNA sequences from three loci for each symbiont, we compared the genetic structure of mycobionts and photobionts. Phylogenetic reconstructions and Bayesian clustering methods divided the mycobiont and photobiont data sets into three groups. An amova shows that the genetic variance of the photobiont is best explained by differentiation between temperate and polar regions and that of the mycobiont by an interaction of climatic and geographical factors. By partialling out the relative contribution of climate, geography and codispersal, we found that the most relevant factors shaping the genetic structure of the photobiont are climate and a history of codispersal. Mycobionts in the temperate region are consistently associated with a specific photobiont lineage. We therefore conclude that a photobiont switch in the past enabled C. aculeata to colonize temperate as well as polar habitats. Rare photobiont switches may increase the geographical range and ecological niche of lichen mycobionts by associating them with locally adapted photobionts in climatically different regions and, together with isolation by distance, may lead to genetic isolation between populations and thus drive the evolution of lichens.
Plant systems biology: network matters
Authors: LUCAS MIKAËL , LAPLAZE LAURENT , BENNETT MALCOLM J. 
Published: February 2011

ABSTRACTSystems biology is all about networks. A recent trend has been to associate systems biology exclusively with the study of gene regulatory or protein‐interaction networks. However, systems biology approaches can be applied at many other scales, from the subatomic to the ecosystem scales. In this review, we describe studies at the sub‐cellular, tissue, whole plant and crop scales and highlight how these studies can be related to systems biology. We discuss the properties of system approaches at each scale as well as their current limits, and pinpoint in each case advances unique to the considered scale but representing potential for the other scales. We conclude by examining plant models bridging different scales and considering the future prospects of plant systems biology.
Role of PSBS and LHCSR in Physcomitrella patens acclimation to high light and low temperature
Authors: GEROTTO CATERINA , ALBORESI ALESSANDRO , GIACOMETTI GIORGIO M. , BASSI ROBERTO , MOROSINOTTO TOMAS 
Published: February 2011

ABSTRACTPhotosynthetic organisms respond to strong illumination by activating several photoprotection mechanisms. One of them, non‐photochemical quenching (NPQ), consists in the thermal dissipation of energy absorbed in excess. In vascular plants NPQ relies on the activity of PSBS, whereas in the green algae Chlamydomonas reinhardtii it requires a different protein, LHCSR. The moss Physcomitrella patens is the only known organism in which both proteins are present and active in triggering NPQ, making this organism particularly interesting for the characterization of this protection mechanism. We analysed the acclimation of Physcomitrella to high light and low temperature, finding that these conditions induce an increase in NPQ correlated to overexpression of both PSBS and LHCSR. Mutants depleted of PSBS and/or LHCSR showed that modulation of their accumulation indeed determines NPQ amplitude. All mutants with impaired NPQ also showed enhanced photosensitivity when exposed to high light or low temperature, indicating that in this moss the fast‐responding NPQ mechanism is also involved in long‐term acclimation.
Resistance to Rhizoctonia solani AG‐2‐2 (IIIB) in creeping bentgrass plants transformed with pepper esterase gene PepEST
Authors: Cho K.‐C. , Han Y.‐J. , Kim S.‐J. , Lee S.‐S. , Hwang O.‐J. , Song P.‐S. , Kim Y.‐S. , Kim J.‐I. 
Published: February 2011

A pepper esterase (PepEST) gene was introduced into creeping bentgrass (Agrostis stolonifera) by Agrobacterium‐mediated transformation. Purified recombinant PepEST proteins were sufficient to inhibit the growth of the fungal pathogens Rhizoctonia solani AG2‐2 (IIIB) (causing brown patch) and Sclerotinia homoeocarpa (dollar spot), but not the oomycete responsible for pythium blight, Pythium aphanidermatum. PepEST proteins were most effective against R. solani. After genetic transformation of creeping bentgrass with PepEST, the genomic integration of transgenes bar and PepEST was confirmed by Southern blot analysis, and their expression was also validated by northern blot and western blot analyses. Disease severity on R. solani‐inoculated leaves of transgenic plants was <10% compared to ca. 50% in non‐transgenic plants. Microscopic observation of infected leaves indicated that PepEST inhibited the growth of hyphae upon fungal infection.
Ghrelin receptor (GHS‐R1A) antagonism suppresses both operant alcohol self‐administration and high alcohol consumption in rats
Authors: Landgren Sara , Simms Jeffrey A. , Hyytiä Petri , Engel Jörgen A. , Bartlett Selena E. , Jerlhag Elisabet 
Published: February 2011

ABSTRACTThe mechanisms involved in alcohol use disorders are complex. It has been shown that ghrelin is an important signal for the control of body weight homeostasis, preferably by interacting with hypothalamic circuits, as well as for drug reward by activating the mesolimbic dopamine system. The ghrelin receptor (GHS‐R1A) has been shown to be required for alcohol‐induced reward. Additionally, ghrelin increases and GHR‐R1A antagonists reduce moderate alcohol consumption in mice, and a single nucleotide polymorphism in the GHS‐R1A gene has been associated with high alcohol consumption in humans. However, the role of central ghrelin signaling in high alcohol consumption is not known. Therefore, the role of GHS‐R1A in operant self‐administration of alcohol in rats as well as for high alcohol consumption in Long‐Evans rats and in alcohol preferring [Alko alcohol (AA)] rats was studied here. In the present study, the GHS‐R1A antagonist, JMV2959, was found to reduce the operant self‐administration of alcohol in rats and to decrease high alcohol intake in Long‐Evans rats as well as in AA rats. These results suggest that the ghrelin receptor signaling system, specifically GHS‐R1A, is required for operant self‐administration of alcohol and for high alcohol intake in rats. Therefore, the GHS‐R1A may be a therapeutic target for treatment of addictive behaviors, such as alcohol dependence.
Natural history of chronic hepatitis B REVEALed
Authors: Chen Chien‐Jen , Yang Hwai‐I 
Published: February 2011

AbstractChronic hepatitis B is a worldwide public health challenge. Knowledge of natural history of chronic hepatitis B is important for the management of the disease. A community‐based prospective cohort study was carried out to evaluate the risk predictors of progression of chronic hepatitis B in Taiwan. A total of 23 820 participants were enrolled in 1991–1992 from seven townships in Taiwan. Their serum samples were collected at study entry and tested for hepatitis B surface antigen (HBsAg) and e antigen (HBeAg), antibodies against hepatitis C virus (anti‐HCV), alanine aminotransferase (ALT), and α‐fetoprotein (AFP). A subcohort of 3653 male and female participants who were seropositive for HBsAg and seronegative for anti‐HCV was included in the Risk Evaluation of Viral Load Elevation and Associated Liver Disease/Cancer‐Hepatitis B Virus (REVEAL‐HBV) study. Newly developed cases of cirrhosis and hepatocellular carcinoma (HCC) were ascertained through follow‐up examination and data linkage with profiles of the National Cancer Registry, National Health Insurance Database and Death Certification System. The incidence of both HCC and cirrhosis were significantly associated with serum HBV DNA levels in a dose‐response relationship from < 300 (undetectable) to ≥ 1 000 000 copies/mL. The biological gradients remained significant (P < 0.001) after adjustment for age, sex, habits of cigarette smoking and alcohol drinking, HBeAg serostatus, and serum ALT level at cohort entry. A significant association with risk of cirrhosis and HCC was also observed for HBV genotype, precore G1896A mutant and basal core promoter A1762T/G1764A double mutant. Nomograms have been developed for the long‐term risk prediction of cirrhosis and HCC for patients with chronic hepatitis B. Inactive carriers of HBV have an increased HCC incidence and liver‐related mortality than HBsAg‐seronegative controls. Serum HBV DNA level at study entry is a major predictor of spontaneous seroclearance of HBeAg, HBV DNA and HBsAg. These findings may inform the effective and efficient management of chronic hepatitis B.
The placebo mystique: Implications for clinical trial methodology
Authors: Clifford Vanessa 
Published: February 2011

Aim:  The World Medical Association Declaration of Helsinki states that the use of a placebo in a clinical trial can only be justified ethically when no proven active treatment is available as a comparison. Despite this, placebos remain a popular choice as controls in clinical trials. Recent literature reviews have suggested that reliance on placebos may, in part, be because of methodological misconceptions about the need for placebos to control for the ‘placebo effect’. This study aimed to assess doctors' understanding of the requirements for placebo use in clinical trials.Methods:  Two hundred doctors working in tertiary hospitals in Melbourne, Australia were surveyed in regards to their understanding of the role of the placebo and placebo effects in clinical trials. There was a 72% response rate. Doctors were specifically asked if a placebo was required in a randomised clinical trial, in preference to another form of control, to control for the ‘placebo effect’.Results:  The majority of respondents (62%) incorrectly believed that placebos are essential to control for the ‘placebo effect’ in a randomised clinical trial.Conclusions:  Misconceptions about the methodological requirement for placebos in randomised controlled trials may influence researcher decisions to use placebo controls in unethical situations.
Non‐attendance to the paediatric clinics in a Malaysian tertiary hospital: A sizeable problem and identification of an efficacious intervention
Authors: Jamil Mohammad Tamim , Ismail Nik Zainal Abidin Nik , Zulkifli Azman Bin , Majid Noorizan Abdul , Van Rostenberghe Hans 
Published: February 2011

Aim:  To determine the rate, causes and risk factors of non‐attendance to the paediatric clinic in a tertiary hospital in Malaysia and to determine the efficacy of one telephone call to confirm a new appointment.Methods:  For all non‐attending patients, during a 2‐month period, a pro forma was filled up based on patients' records. During a phone call, additional questions were asked, and a new appointment was offered.Results:  Of 1563 patients who had an appointment, 497 (31.8%) were non‐attendees. Weather conditions, the sub‐specialty and timing (morning or afternoon) had a significant effect on non‐attendance. Forgetfulness was the main cause. Only 160 patients could be successfully contacted. Among the contactable patients, 55 already had an appointment, and 10 had reasons not to get a new appointment. Of the 95 remaining patients, 73 (76.8%) attended the new appointment.Conclusion:  The non‐attendance rate was high. One telephone call had a reasonable efficacy for the contactable patients, but because a high number of patients were not contactable, overall effectiveness was poor.
Shining D' light on chronic kidney disease: Mechanisms that may underpin the cardiovascular benefit of vitamin D
Authors: PETCHEY WILLIAM G , JOHNSON DAVID W , ISBEL NICOLE M 
Published: February 2011

ABSTRACTHypovitaminosis D is a significant health‐care burden worldwide, particularly in susceptible populations such as those with chronic kidney disease (CKD). Recent epidemiological studies have identified that both higher serum vitamin D concentrations and use of vitamin D supplements may confer a survival benefit both in terms of all‐cause and cardiovascular mortality. There is potential to investigate this inexpensive therapy for the CKD population, which suffers excessive cardiovascular events, although the mechanisms explaining this link have yet to be fully elucidated. This review discusses potential mechanisms identified in the basic science literature that may provide important insights into how vitamin D may orchestrate a change in cardiovascular risk profile through such diverse mechanisms as inflammation, atherogenesis, glucose homeostasis, vascular calcification, renin‐angiotensin regulation and alterations in cardiac physiology. Where available, the clinical translation of these concepts to intervention trials in the CKD population will be reviewed.
Interventional radiology of pleural diseases
Authors: MATIN TAHREEMA N. , GLEESON FERGUS V. 
Published: February 2011

ABSTRACTImage‐guided pleural procedures are important in both the diagnosis and management of pleural disease. Pleural aspiration, biopsy and drainage are all proven to be safer and more efficacious using image guidance. The aim of this article is to review common image‐guided pleural techniques and the evidence base for their application in clinical practice.
Virulence quenching with a prenylated isoflavanone renders the Malagasy legume Dalbergia pervillei resistant to Rhodococcus fascians
Authors: Rajaonson Sanda , Vandeputte Olivier M. , Vereecke Danny , Kiendrebeogo Martin , Ralambofetra Eliane , Stévigny Caroline , Duez Pierre , Rabemanantsoa Christian , Mol Adeline , Diallo Billo , Baucher Marie , El Jaziri Mondher 
Published: February 2011

SummaryThe phytopathogenic Actinomycete Rhodococcus fascians induces leafy galls on a wide range of hosts, causing major economical losses in the ornamentals industry. Although differences in the responsivity occur within species, no plant tested so far could be considered resistant to R. fascians strain D188 infection. Here, we observed that members of the genus Dalbergia, which belong to the Fabaceae, did not develop leafy galls when challenged with R. fascians and we set out to unravel the mechanism of this recalcitrance. Whereas organic extracts of Dalbergia tissues exhibited toxicity towards the bacteria, more importantly, dichloromethane bark extracts inhibited the induction of bacterial virulence gene expression without any apparent loss of viability, illustrating that resistance is likely multifactorial. The virulence quencher was identified as a new prenylated isoflavanone, termed perbergin, and specifically targeted the AttR regulon (a LysR‐type transcriptional regulator) which is imperative for the switch of R. fascians from an epiphytic to a pathogenic lifestyle. The mode of action of perbergin demonstrated that just like in Gram‐negative host–microbe interactions, also in Gram‐positive phytopathogens autoregulation is being targeted by the plant as an efficient means of defence. Moreover, the identification of perbergin opens the path to disease control in affected nurseries.
The Instructor Element of GIS Instruction at US Colleges and Universities
Authors: Fagin Todd D. , Wikle Thomas A. 
Published: February 2011

AbstractOver the last two decades, higher education has made substantial investments in GIS education through equipment and software purchases, upgrades to teaching facilities, and the creation of innovative academic programs such as certificates and degrees. However, comparatively less attention and fewer resources have been directed towards what might be called the “instructor element” of GIS instruction. In this article we look at the preparation and ongoing professional development of GIS educators through a survey of 270 individuals teaching GIS at US colleges and universities. Along with assessing the education and professional background of GIS instructors, we evaluate their perceptions concerning the importance of various GIS subject areas. Our findings demonstrate considerable breadth in the range of education and experience held by faculty members who are presently teaching GIS courses. In evaluating the importance placed on GIS teaching elements, we found little variation among individuals according to their institution type or educational attainment. However, significant differences in the perceived importance of GIS teaching areas were found across disciplinary areas.
Alternative Areal Decompositions: An Empirical Study
Authors: Lee Ickjai , Breitkreutz David 
Published: February 2011

AbstractThis article compares area data representation with several areal decomposition alternatives in order to determine any improvement to efficiency at the expense of accuracy. This article utilizes the Voronoi diagram as an underlying base data model, combines polygon partitioning and the Voronoi diagram to provide several alternative hybrid areal decompositions, and empirically examines the efficiency and effectiveness performance of these alternatives for popular GIS operations: geometrical, topological and reclassification operations. Experimental results reveal that most areal decomposition alternatives are likely to produce significant benefits in time efficiency while generating different levels of accuracy.
Automatic Representation of Geographical Data from a Semantic Point of View through a New Ontology and Classification Techniques
Authors: Fonseca Rainer Larin , Llano Eduardo Garea 
Published: February 2011

AbstractProviding Geographical Information Systems with mechanisms for processing geo‐data based on their semantics may help to solve problems like heterogeneity. This is because GIS could process geo‐data focusing on their meaning and not on their syntax and/or structure. An important aspect for achieving these objectives is the establishment of an automatic means of correspondence between geo‐data and their conceptualization in Higher Levels Ontologies (HLO). In this article, a new type of Ontology is proposed (Data‐Representation Ontology (DRO)). This Ontology describes the semantic embedded in geo‐data, which cannot be represented in current types of Ontologies. Across this Ontology, heterogeneous geographical data can be integrated in the semantic space contributing positively to the development of solutions for the problems of interoperability between heterogeneous systems. Likewise, we propose a new method for the automatic generation of the DRO and its interrelationships with HLO, based on pattern classification techniques. The experiments show that once the DRO is generated, the classifier can classify all data correctly. Thus, these data are semantically enriched. Moreover, this article shows how the topological relationships can enrich the semantics in the generated Ontology and increase the effectiveness of spatial analysis.
Optimal Routefinding with Unlimited Possible Directions of Movement
Authors: Dean Denis J. 
Published: February 2011

AbstractFinding optimal paths through raster databases is limited by the very nature of the raster data itself. This limitation restricts the possible directions of movement through the database from the infinite possibilities found in the real world to a finite number of possibilities defined by the cell‐to‐cell movement that characterizes raster databases. A Triangulated Irregular Network (TIN)‐based alternative optimization model that allows unlimited possible directions of movement is presented. While not without its own limitations, this new approach offers a viable alternative to raster‐based optimal routefinding.