bluuebunny/crossref_metadata_2025_split huggingface dataset:
Reliability of genetic bottleneck tests for detecting recent population declines
Authors: PEERY M. ZACHARIAH , KIRBY REBECCA , REID BRENDAN N. , STOELTING RICKA , DOUCET‐BËER ELENA , ROBINSON STACIE , VÁSQUEZ‐CARRILLO CATALINA , PAULI JONATHAN N. , PALSBØLL PER J. 
Published: May 2012

AbstractThe identification of population bottlenecks is critical in conservation because populations that have experienced significant reductions in abundance are subject to a variety of genetic and demographic processes that can hasten extinction. Genetic bottleneck tests constitute an appealing and popular approach for determining if a population decline has occurred because they only require sampling at a single point in time, yet reflect demographic history over multiple generations. However, a review of the published literature indicates that, as typically applied, microsatellite‐based bottleneck tests often do not detect bottlenecks in vertebrate populations known to have experienced declines. This observation was supported by simulations that revealed that bottleneck tests can have limited statistical power to detect bottlenecks largely as a result of limited sample sizes typically used in published studies. Moreover, commonly assumed values for mutation model parameters do not appear to encompass variation in microsatellite evolution observed in vertebrates and, on average, the proportion of multi‐step mutations is underestimated by a factor of approximately two. As a result, bottleneck tests can have a higher probability of ‘detecting’ bottlenecks in stable populations than expected based on the nominal significance level. We provide recommendations that could add rigor to inferences drawn from future bottleneck tests and highlight new directions for the characterization of demographic history.
Effects of vicariant barriers, habitat stability, population isolation and environmental features on species divergence in the south‐western Australian coastal reptile community
Authors: EDWARDS D. L. , KEOGH J. S. , KNOWLES L. L. 
Published: May 2012

AbstractIdentifying explicit hypotheses regarding the factors determining genetic structuring within species can be difficult, especially in species distributed in historically dynamic regions. To contend with these challenges, we use a framework that combines species distribution models, environmental data and multi‐locus genetic data to generate and explore phylogeographic hypotheses for reptile species occupying the coastal sand‐dune and sand‐plain habitats of the south‐western Australian biodiversity hotspot, a community which has both a high diversity of endemics and has varied dramatically in spatial extent over time. We use hierarchical amova, summary statistic and distance‐based analyses to explicitly test specific phylogeographic hypotheses. Namely, we test if biogeographic vicariance across barriers, habitat stability, population isolation along a linear habitat or fragmentation across different environments can explain genetic divergence within five co‐distributed squamate reptile species. Our results show that patterns of genetic variation reflect complex and species‐specific interactions related to the spatial distribution of habitats present currently and during repeated glacial minima, as opposed to being associated with historical factors such as habitat stability between glacial and inter‐glacial periods or vicariant barriers. We suggest that the large impact of habitat characteristics over time (i.e. relative levels of habitat connectivity, climatic gradients and spatial heterogeneity of soil types) reflects the ecological restrictions of the sand‐dune and sand‐plain reptile communities and may explain the lack of concordance across taxa. The study demonstrates the general utility of the approach for assemblage‐level, as well as single species, phylogeographic study, including its usefulness for exploring biologically informed hypotheses about what factors have influenced patterns of genetic variation.
Multiple lessons from the multiple functions of a regulator of type III secretion system assembly in the plant pathogen Pseudomonas syringae
Authors: Wei Hai‐Lei , Collmer Alan 
Published: May 2012

SummaryThe assembly of type III secretion systems (T3SSs), which inject bacterial effector proteins into the cytosol of animal and plant hosts, is a highly regulated process. Animal pathogens use a length‐control protein to produce T3SS needles of fixed length and then a second regulator, such as YopN in Yersinia spp, to mediate host contact‐dependent effector delivery. For Pseudomonas syringae and other plant pathogens, regulation of the assembly process differs because the T3SS pilus must grow through variably thick plant cell walls before contacting the host plasma membrane. In this issue of Molecular Microbiology, Crabill et al. (2012) report evidence that the YopN homologue HrpJ is a multifunctional regulator of T3SS assembly in DC3000. A hrpJ mutant hyper‐secretes pilus protein and no longer secretes four translocator proteins in culture, and it fails to inject effectors in planta. As with other proteins in this class, HrpJ is itself a T3SS substrate, but secretion‐incompetent forms retain regulatory function. However, HrpJ is unusual in suppressing innate immune responses within host cells, as demonstrated with transgenic plants. The multiple capabilities of HrpJ appear to couple host contact sensing with pilus length control and translocator secretion while also contributing to immunity suppression early in the interaction.
Short‐term effects of CO2 and O2 on citrate metabolism in illuminated leaves
Authors: TCHERKEZ GUILLAUME , MAHÉ ALINE , GUÉRARD FLORENCE , BOEX‐FONTVIEILLE EDOUARD R. A. , GOUT ELISABETH , LAMOTHE MARLÈNE , BARBOUR MARGARET M. , BLIGNY RICHARD 
Published: May 2012

ABSTRACTAlthough there is now a considerable literature on the inhibition of leaf respiration (CO2 evolution) by light, little is known about the effect of other environmental conditions on day respiratory metabolism. In particular, CO2 and O2 mole fractions are assumed to cause changes in the tricarboxylic acid pathway (TCAP) but the amplitude and even the direction of such changes are still a matter of debate. Here, we took advantage of isotopic techniques, new simple equations and instant freeze sampling to follow respiratory metabolism in illuminated cocklebur leaves (Xanthium strumarium L.) under different CO2/O2 conditions. Gas exchange coupled to online isotopic analysis showed that CO2 evolved by leaves in the light came from ‘old’ carbon skeletons and there was a slight decrease in 13C natural abundance when [CO2] increased. This suggested the involvement of enzymatic steps fractionating more strongly against 13C and thus increasingly limiting for the metabolic respiratory flux as [CO2] increased. Isotopic labelling with 13C2‐2,4‐citrate lead to 13C‐enriched Glu and 2‐oxoglutarate (2OG), clearly demonstrating poor metabolism of citrate by the TCAP. There was a clear relationship between the ribulose‐1,5‐bisphosphate oxygenation‐to‐carboxylation ratio (vo/vc) and the 13C commitment to 2OG, demonstrating that 2OG and Glu synthesis via the TCAP is positively influenced by photorespiration.
A review of training opportunities for ultrasonography in low and middle income countries
Authors: LaGrone Lacey N. , Sadasivam Vijay , Kushner Adam L. , Groen Reinou S. 
Published: May 2012

AbstractObjective  To review the current training opportunities for ultrasound use for health workers practising in low‐ and middle‐income countries (LMICs).Methods  A PubMed search using terms ultrasound, sonography, echocardiography, developing country/countries, developing world, low resource settings, low income country/countries, training and education was conducted. Articles from 2000 to 2011 that included data on ultrasonography training were eligible for inclusion.Results  This review shows that most ultrasound scans are performed by generalist and obstetric physicians and even non‐medical personnel with little to no formal training in ultrasonography. The spectrum of ultrasonography training described spanned from no formal training to formal certification and residency programmes. All courses included some component of didactics and hands‐on training. Follow‐up of trainee skills ranged from none, to telemedicine case review, to formal re‐evaluations and intensive refresher courses. Ultrasonographic training in LMICs often does not meet the WHO criteria such as the number of scans under supervision and length of training programme recommended by WHO. Nevertheless, some programmes manage to have excellent outcomes with regard to diagnostic accuracy and retention of knowledge by trained personnel.Conclusion  Regulation and quality control of training in ultrasound skills for those working in LMICs can be improved. Research on effective training and follow‐up should be encouraged.
Plasmodium vivax Duffy binding protein: baseline antibody responses and parasite polymorphisms in a well‐consolidated settlement of the Amazon Region
Authors: Kano Flora S. , Sanchez Bruno A. M. , Sousa Tais N. , Tang Michaelis L. , Saliba Jéssica , Oliveira Fernando M. , Nogueira Paulo A. , Gonçalves Alessandra Q. , Fontes Cor J. F. , Soares Irene S. , Brito Cristiana F. A. , Rocha Roberto S. , Carvalho Luzia H. 
Published: May 2012

AbstractObjective To investigate risk factors associated with the acquisition of antibodies against Plasmodium vivax Duffy binding protein (PvDBP) – a leading malaria vaccine candidate – in a well‐consolidated agricultural settlement of the Brazilian Amazon Region and to determine the sequence diversity of the PvDBP ligand domain (DBPII) within the local malaria parasite population.Methods Demographic, epidemiological and clinical data were collected from 541 volunteers using a structured questionnaire. Malaria parasites were detected by conventional microscopy and PCR, and blood collection was used for antibody assays and molecular characterisation of DBPII.Results The frequency of malaria infection was 7% (6% for P. vivax and 1% for P. falciparum), with malaria cases clustered near mosquito breeding sites. Nearly 50% of settlers had anti‐PvDBP IgG antibodies, as detected by enzyme‐linked immunosorbent assay (ELISA) with subject’s age being the only strong predictor of seropositivity to PvDBP. Unexpectedly, low levels of DBPII diversity were found within the local malaria parasites, suggesting the existence of low gene flow between P. vivax populations, probably due to the relative isolation of the studied settlement.Conclusion The recognition of PvDBP by a significant proportion of the community, associated with low levels of DBPII diversity among local P. vivax, reinforces the variety of malaria transmission patterns in communities from frontier settlements. Such studies should provide baseline information for antimalarial vaccines now in development.
Historical habitat connectivity affects current genetic structure in a grassland species
Authors: Münzbergová Z. , Cousins S. A. O. , Herben T. , Plačková I. , Mildén M. , Ehrlén J. 
Published: May 2012

AbstractMany recent studies have explored the effects of present and past landscape structure on species distribution and diversity. However, we know little about the effects of past landscape structure on distribution of genetic diversity within and between populations of a single species. Here we describe the relationship between present and past landscape structure (landscape connectivity and habitat size estimated from historical maps) and current genetic structure in a perennial herb, Succisa pratensis. We used allozymes as co‐dominant markers to estimate genetic diversity and deviation from Hardy–Weinberg equilibrium in 31 populations distributed within a 5 km2 agricultural landscape. The results showed that current genetic diversity of populations was related to habitat suitability, habitat age, habitat size and habitat connectivity in the past. The effects of habitat age and past connectivity on genetic diversity were in most cases also significant after taking the current landscape structure into account. Moreover, current genetic similarity between populations was affected by past connectivity after accounting for current landscape structure. In both cases, the oldest time layer (1850) was the most informative. Most populations showed heterozygote excess, indicating disequilibrium due to recent gene flow or selection against homozygotes. These results suggest that habitat age and past connectivity are important determinants of distribution of genetic diversity between populations at a scale of a few kilometres. Landscape history may significantly contribute to our understanding of distribution of current genetic structure within species and the genetic structure may be used to better understand landscape history, even at a small scale.
Meta‐analysis of amiodarone versus beta‐blocker as a prophylactic therapy against atrial fibrillation following cardiac surgery
Authors: Zhu J. , Wang C. , Gao D. , Zhang C. , Zhang Y. , Lu Y. , Gao Y. 
Published: May 2012

AbstractBackgroundCurrent guidelines recommend beta‐blocker as the first‐line preventive treatment of atrial fibrillation (AF) after cardiac surgery; if beta‐blocker therapy is contraindicated, then amiodarone is recommended. There is still lack of strong evidence of directly comparing the efficacy of amiodarone and beta‐blocker in preventing postoperative AF (POAF).AimThis meta‐analysis was to determine whether amiodarione and beta‐blocker are equally effective and safe, or one is superior in preventing POAF.MethodsWe searched the Medline, Web of Science, Cochrane Library databases and clinical trial databases for related articles published from January 1990 to October 2011. The primary outcome was development of AF after cardiac surgery. We used random‐effects model when there was significant heterogeneity between trials and fixed‐effects method when heterogeneity was negligible. Moreover, subgroup and sensitivity analyses were also performed.ResultsWe identified totally six trials, which involved 1033 patients. The amiodarone group did not significantly differ from the beta‐blocker group in AF occurrence (risk ratio 0.77, 95% confidence interval 0.55 to 1.06, P = 0.11) or the length of hospital stay (weighted mean difference −0.05 day, 95% confidence interval −0.64 to 0.54, P = 0.86). Subgroup analysis stratified by different beta‐blockers revealed that amiodarone significantly improved POAF as compared with propranolol. In addition, there was no difference in adverse events after operation.ConclusionThese data indicate that the occurrence of AF and length of hospital stay after surgery are similar in the amiodarone and beta‐blocker groups.
Motor endplate disease affects neuromuscular junction maturation
Authors: Caillol Ghislaine , Vacher Hélène , Musarella Magali , Bellouze Sarah , Dargent Bénédicte , Autillo‐Touati Amapola 
Published: May 2012

AbstractPostnatal formation of the neuromuscular synapse requires complex interactions among nerve terminal, muscle fibres and terminal Schwann cells. In motor endplate disease (med) mice, neuromuscular transmission is severely impaired without alteration of axonal conduction and a lethal paralytic phenotype occurs during the postnatal period. The med phenotype appears at a crucial stage of the neuromuscular junction development, corresponding to the increase in terminal Schwann cell number, the elimination of the multiple innervations and the pre‐ and postsynaptic maturation. Here we investigated the early cellular and molecular consequences of the med mutation on neuromuscular junction development. We observed that cellular defects preceded overt clinical phenotype. The first detectable cellular effect of the mutation at the onset of the clinical phenotype was a drastic reduction in the number of terminal Schwann cells, in part due to an increase in glial apoptosis, and a delayed maturation of motor endplates. We also showed that, in terminally ill animals, mono‐innervation was not achieved, synaptic vesicles had accumulated in the presynaptic compartment and, finally, the size of motor endplates was reduced. All together, our findings suggested that the clinical weakness in these mutant mice was likely to be related to postnatal structural abnormalities of the neuromuscular junction maturation.
When News Matters: Media Effects on Public Support for European Union Enlargement in 21 Countries
Authors: AZROUT RACHID , VAN SPANJE JOOST , DE VREESE CLAES 
Published: May 2012

AbstractFirst, this study tests for media effects on support for EU enlargement in a natural setting, while including actual media content in the analysis. Second, the moderation by anti‐immigrant attitudes of media effects is tested, as it is argued that perceptions of ‘others’ influences how new information on enlargement is received. The study draws on a two‐wave panel survey and a media content analysis in 21 countries. The results suggest there is a media effect, although not from individual exposure but from the information environment. In addition, individuals with stronger anti‐immigrant attitudes are more strongly affected by a negative information environment.
Whose Rule, Whose Law? Contested Statehood, External Leverage and the European Union's Rule of Law Mission in Kosovo*
Authors: PAPADIMITRIOU DIMITRIS , PETROV PETAR 
Published: May 2012

AbstractThe article discusses the projection of European Union (EU) power under conditions of contested statehood in its ‘near abroad’. Using the EU's mission in Kosovo (EULEX) as a case study, the article unpacks the various levers of external EU influence and explores the conditions under which European policy‐makers become entangled in the ‘existential discourse’ of highly polarized societies with competing statehood claims. The contestation of these claims (both domestically and internationally) produces significant challenges for EU actorness, affecting both self‐ascribed (internal to the EU) and external (amongst the EU's interlocutors) aspects of EU presence, which, in turn, shapes the EU's ability to deploy and co‐ordinate its capabilities on the ground. It is by reference to this ‘presence–capabilities’ nexus that this article seeks to conceptualize the limitations of the planning and early deployment of EULEX in Kosovo.
Habituation of rapid sympathetic response to aversive timbre eliminated by change in basal sympathovagal balance
Authors: Ooishi Yuuki , Kashino Makio 
Published: May 2012

AbstractWe studied the difference in the habituation of the rapid sympathetic response to slightly and highly aversive timbres in 68 males. We measured the decrease in the blood volume pulse amplitude (BVP response) as the rapid sympathetic response and the low‐ (0.04–0.15 Hz) to high‐ (0.15–0.40 Hz) frequency (LF/HF) ratio of heart rate variability as the sympathovagal balance. The BVP response was suppressed for slightly aversive timbres that had been presented once before, but not for a highly aversive timbre. In contrast, the prior presentation of a highly aversive timbre enhanced the BVP response to a slightly aversive timbre. Only a highly aversive timbre reduced the LF/HF ratio. We suggest that the lack of habituation of the rapid sympathetic response to an aversive timbre is the result of the balance between the effects of the increase caused by the change in sympathovagal balance to vagal dominance and the decrease caused by classical habituation.
Right frontal cortical asymmetry predicts empathic reactions: Support for a link between withdrawal motivation and empathy
Authors: Tullett Alexa M. , Harmon‐Jones Eddie , Inzlicht Michael 
Published: May 2012

AbstractDepression, diminished positive affect, and exaggerated negative affect have all been linked to right frontal cortical asymmetry as measured by electroencephalography (EEG). Emerging evidence, however, suggests that right frontal EEG asymmetry might be linked to empathic responding. EEG was used to assess baseline asymmetries in frontal brain activity. Participants viewed images associated with a charity and then rated their sadness, personal distress, perspective‐taking, and empathic concern towards the images. We found that baseline measures of right frontal asymmetry were a significant predictor of empathic concern, a relationship that was mediated by feelings of sadness. These results provide a more complex view of right frontal asymmetry and suggest that this pattern of brain activity might facilitate sensitivity towards the suffering of others.
In The Literature: Home Birth: Safe Enough, But Not for the First Baby
Authors: Buekens, Pierre , Keirse, Marc J.N.C. 
Published: May 2012

AbstractThe “Birthplace in England” study compared low‐risk pregnancies by planned place of birth at the onset of labor: home, midwifery unit, or obstetric unit. The study showed that childbirth interventions were less frequent in all nonobstetric settings than in obstetric units, confirming what has been noted elsewhere. For parous women, there was no difference in perinatal outcomes by place of birth. For nulliparous women, perinatal outcomes were similar in midwifery and obstetric units, but the frequency of poor outcomes with planned home births was higher. The major strengths of the study are its prospective design and large sample size. The results support providing choices to women, but suggest that women should not be encouraged to give birth at home for their first baby. (BIRTH 39:2 June 2012)
National Institute on Aging at Middle Age—Its Past, Present, and Future
Authors: Nagy Catherine L. , Bernard Marie A. , Hodes Richard J. 
Published: May 2012

The National Institute on Aging (NIA) at the National Institutes of Health (NIH) leads the federal effort conducting and supporting research on aging. It is also designated as the lead within NIH for research on Alzheimer's disease. Since NIA's establishment in 1974, it has grown to a billion dollar enterprise featuring a balanced program of basic, clinical, and behavioral and social science. Investigator‐initiated research and strategic investments have been critical to the NIA's success in bringing new insights and understandings to aging processes and diseases and conditions associated with advancing age. In recent years, constraints in the growth of resources have posed new challenges as the NIA and NIH leadership seek to maintain a robust and productive program. This article will review the history of the NIA, discuss current programs and priorities, and point to new directions in research, looking ahead.
Equity‐Based Incentives and Supply Chain Buy‐Back Contracts*
Authors: Dai Tinglong , Li Zhaolin , Sun Daewon 
Published: May 2012

ABSTRACTWe analyze the effect of equity‐based incentives in a supply chain with a downstream firm and an upstream supplier. By using the operational decision as a signal to influence external investors’ beliefs, the downstream firm's manager intends to maximize a convex combination of the interim share price and the terminal cash flows. We show that equity‐based incentives create a side effect. Specifically, with a universal buy‐back contract, the deadweight loss of signaling induced by equity‐based incentives could spread throughout the supply chain and cause chain‐wide damages. To mitigate such undesirable consequences, we propose a new mechanism to eliminate the inefficiency. We derive the optimal mechanism that maximizes the downstream firm's profits subject to the constraint that the supply chain efficiency is not undermined. In contrast to the full‐information benchmark, this mechanism gives positive surplus to the supplier. [Submitted: January 5, 2011. Revisions received: June 20, 2011; December 11, 2011. Accepted: December 22, 2011.]