bluuebunny/crossref_metadata_2025_split huggingface dataset:
Environment determines evolutionary trajectory in a constrained phenotypic space
Authors: Fraebel David T. , Mickalide Harry , Schnitkey Diane , Merritt Jason , Kuhlman Thomas E , Kuehn Seppe 
Published: December 2016

AbstractConstraints on phenotypic variation limit the capacity of organisms to adapt to the multiple selection pressures encountered in natural environments. To better understand evolutionary dynamics in this context, we selectEscherichia colifor faster migration through a porous environment, a process which depends on both motility and growth. We find that a trade-off between swimming speed and growth rate constrains the evolution of faster migration. Evolving faster migration in rich medium results in slow growth and fast swimming, while evolution in minimal medium results in fast growth and slow swimming. In each condition parallel genomic evolution drives adaptation through different mutations. We show that the trade-off is mediated by antagonistic pleiotropy through mutations that affect negative regulation. A model of the evolutionary process shows that the genetic capacity of an organism to vary traits can qualitatively alter the evolutionary trajectory when selection pressures are complex.
Canonical and cross-reactive binding of NK cell inhibitory receptors to HLA-C allotypes is dictated by peptides bound to HLA-C
Authors: Sim Malcolm J. W. , Malaker Stacy A. , Khan Ayesha , Stowell Janet M. , Shabanowitz Jeffrey , Peterson Mary E. , Rajagopalan Sumati , Hunt Donald F. , Altmann Daniel M. , Long Eric O. , Boyton Rosemary J. 
Published: December 2016

AbstractBackgroundHuman natural killer (NK) cell activity is regulated by a family of killer-cell Ig-like receptors (KIR) that bind human leucocyte antigen (HLA) class I. Combinations of KIR and HLA genotypes are associated with disease, including susceptibility to viral infection and disorders of pregnancy. KIR2DL1 binds HLA-C alleles of group C2 (Lys80) and KIR2DL2 and KIR2DL3 bind HLA-C alleles of group C1 (Asn80). However, this model does not capture allelic diversity in HLA-C or the impact of HLA-bound peptides. The goal of this study was to determine the extent to which the endogenous HLA-C peptide repertoire can influence the specific binding of inhibitory KIR to HLA-C allotypes.ResultsThe impact of HLA-C bound peptide on inhibitory KIR binding was investigated taking advantage of the fact that HLA-C*05:01 (HLA-C group 2, C2) and HLA-C*08:02 (HLA-C group 1, C1) have identical sequences apart from the key KIR specificity determining epitope at residues 77 and 80. Endogenous peptides were eluted from HLA-C*05:01 and used to test the peptide dependence of KIR2DL1 and KIR2DL2/3 binding to HLA-C*05:01 and HLA-C*08:02 and subsequent impact on NK cell function. Specific binding of KIR2DL1 to the C2 allotype occurred with the majority of peptides tested. In contrast, KIR2DL2/3 binding to the C1 allotype occurred with only a subset of peptides. Cross-reactive binding of KIR2DL2/3 with the C2 allotype was restricted to even fewer peptides. Unexpectedly, two peptides promoted binding of the C2 allotype-specific KIR2DL1 to the C1 allotype. We showed that presentation of endogenous peptides, or predicted HIV Gag peptides, by HLA-C can promote KIR cross-reactive binding.ConclusionsKIR2DL2/3 binding to C1 is more peptide selective than that of KIR2DL1 binding to C2, which provides an explanation for why KIR2DL3–C1 interactions appear weaker than KIR2DL1–C2. In addition, cross-reactive binding of KIR is characterized by even higher peptide selectivity. We demonstrate a hierarchy of functional peptide selectivity of KIR–HLA-C interactions with relevance to NK cell biology and human disease associations. This selective peptide sequence-driven binding of KIR provides a potential mechanism for pathogen as well as self-peptide to modulate NK cell activation through altering levels of inhibition.
Anisotropy parameter inversion in vertical axis of symmetry media using diffractions
Authors: bin Waheed Umair , Stovas Alexey , Alkhalifah Tariq 
Published: December 2016

ABSTRACTDiffractions play a vital role in seismic processing as they can be utilized for high‐resolution imaging applications and analysis of subsurface medium properties like velocity. They are particularly valuable for anisotropic media as they inherently possess a wide range of dips necessary to resolve the angular dependence of velocity. However, until recently, the focus of diffraction imaging or inversion algorithms have been only on the isotropic approximation of the subsurface. Using diffracted waves, we develop a framework to invert for the effective η model. This effective model is obtained through scanning over possible effective η values and selecting the one that best fits the observed moveout curve for each diffractor location. The obtained effective η model is then converted to an interval η model using a Dix‐type inversion formula. The inversion methodology holds the potential to reconstruct the true η model with sufficiently high accuracy and resolution properties. However, it relies on an accurate estimation of diffractor locations, which in turn requires good knowledge of the background velocity model. We test the effectiveness and applicability of our method on the vertical transverse isotropic Marmousi model. The inversion results yield a reasonable match even for the complex Marmousi model.
The first post‐injection seismic monitor survey at the Ketzin pilot CO2 storage site: results from time‐lapse analysis
Authors: Huang Fei , Bergmann Peter , Juhlin Christopher , Ivandic Monika , Lüth Stefan , Ivanova Alexandra , Kempka Thomas , Henninges Jan , Sopher Daniel , Zhang Fengjiao 
Published: December 2016

ABSTRACTThe injection of CO2 at the Ketzin pilot CO2 storage site started in June 2008 and ended in August 2013. During the 62 months of injection, a total amount of about 67 kt of CO2 was injected into a saline aquifer. A third repeat three‐dimensional seismic survey, serving as the first post‐injection survey, was acquired in 2015, aiming to investigate the recent movement of the injected CO2. Consistent with the previous two time‐lapse surveys, a predominantly west–northwest migration of the gaseous CO2 plume in the up‐dip direction within the reservoir is inferred in this first post‐injection survey. No systematic anomalies are detected through the reservoir overburden. The extent of the CO2 plume west of the injection site is almost identical to that found in the 2012 second repeat survey (after injection of 61 kt); however, there is a significant decrease in its size east of the injection site. Assessment of the CO2 plume distribution suggests that the decrease in the size of the anomaly may be due to multiple factors, such as limited vertical resolution, CO2 dissolution, and CO2 migration into thin layers, in addition to the effects of ambient noise. Four‐dimensional seismic modelling based on dynamic flow simulations indicates that a dynamic balance between the newly injected CO2 after the second repeat survey and the CO2 migrating into thin layers and being dissolved was reached by the time of the first post‐injection survey. In view of the significant uncertainties in CO2 mass estimation, both patchy and non‐patchy saturation models for the Ketzin site were taken into consideration.
Meta‐corridor solutions for climate‐vulnerable plant species groups in South Korea
Authors: Choe Hyeyeong , Thorne James H. , Hijmans Robert , Kim Jiyoen , Kwon Hyuksoo , Seo Changwan 
Published: December 2016

Summary

Vulnerability assessments can provide useful information for the establishment of climate change adaptation strategies. We performed spatial vulnerability assessments for multiple plant species that incorporate potential range shifts to areas of future suitable climate. We conducted the assessments at a national level for plant species organized into vulnerable species groups. We then identified a climate meta‐corridor for each vulnerable group that could potentially be a pathway for multiple species.

We estimated climate suitability for 2297 South Korean terrestrial plant species under current climate conditions and climate projections for 2050 using the Multivariate Adaptive Regression Splines multiresponse species distribution model. We classified the plants into five groups based on their current spatial distribution patterns: centrally located species, wide‐range species, coastal mountain species, montane species, and lowland species. Three vulnerability assessment components — exposure, spatial disruption, and dispersal pressure — were used to calculate the spatial vulnerability of each species. Vulnerability values were averaged by group. We identified climate meta‐corridors that would link current suitable areas to future climatically suitable areas, and tested the corridors for multi‐species accessibility.

The vulnerability assessment indicates that coastal mountain, montane, and lowland species groups, comprising 37% of all modelled species, are the most vulnerable to climate change. The climate meta‐corridor for each group overlaps at least some portion of 83% or more of its species' current modelled ranges. The current and future climate‐suitable areas for the lowland species group have very little spatial overlap, suggesting a high priority should be placed on the corridor identified for these species. We found that the destinations of the climate corridors converge, raising questions about large numbers of species moving to limited areas, and that transboundary corridor modelling is needed on the Korean Peninsula.

Policy implications. Each of the three meta‐corridors has unique policy implications: assisted migration for the highest elevation species for the montane; significant conservation and restoration work for the lowland; and perhaps no direct intervention but monitoring to evaluate effectiveness of the relatively intact habitats of the coastal mountain meta‐corridor. Overall, implementation policies for climate connectivity will be context‐dependent, requiring different approaches dependent on local and regional conditions and the species targeted.
Predicting the global incidence of seed desiccation sensitivity
Authors: Wyse Sarah V. , Dickie John B. 
Published: December 2016

Summary

The ability of seeds to tolerate desiccation plays an important role in plant regeneration ecology. Globally, the majority of species produce desiccation‐tolerant (orthodox) seeds, while comparatively few produce desiccation‐sensitive (recalcitrant) seeds that are unable to survive dehydration. The trait has important implications for species conservation, as desiccation‐sensitive species cannot be conserved using traditional seed banking techniques. In addition, these species may be less resilient to the increases in droughts predicted for some regions under climate change scenarios.

The best available resource on seed desiccation tolerance is the Royal Botanic Gardens, Kew's Seed Information Database. This database contains seed desiccation‐sensitivity data for over 18 000 taxa, approximately 3% of which have desiccation‐sensitive seeds. However, this database is likely biased towards desiccation‐tolerant species. Previous attempts to estimate the proportion of seed plants with desiccation‐sensitive seeds have ranged from 7% to 50%. Here, we aimed to overcome sampling bias to derive a best estimate for the proportion of seed plants with desiccation‐sensitive seeds, based on current data.

We used a recently developed method, based on taxonomic relatedness, to account for sampling bias and estimate the proportion of seed plants with desiccation‐sensitive seeds. As a comparison, given that seed desiccation sensitivity is strongly related to habitat, we repeated our analyses using habitat as a basis.

The predictions from our taxonomy‐based models ranged between estimates of 7·5% and 19·6% of the world's seed‐plant species with desiccation‐sensitive seeds, depending on model type, while the habitat‐based models suggested a value of approximately 8%. Our evidence suggests that, based on current data, the best estimate of the proportion of species with desiccation‐sensitive seeds is likely to be approximately 8%. Tropical and subtropical moist broadleaf forests had the highest incidence of seed desiccation sensitivity, where an estimated 18·5% of the seed‐plant flora possessed the trait.

Synthesis. Alongside our estimation of the numbers of species with desiccation‐sensitive seeds, we provide data on taxa and habitats where this trait may be most prevalent. These findings can be used to support conservation planning, particularly with respect to providing decision support for in and ex situ conservation techniques.
Contrasting mass‐ratio vs. niche complementarity effects on litter C and N loss during decomposition along a regional climatic gradient
Authors: García‐Palacios Pablo , Shaw E. Ashley , Wall Diana H. , Hättenschwiler Stephan 
Published: December 2016

Summary

The mass‐ratio and niche complementarity mechanisms drive the influence of litter trait diversity on decomposition. However, the implications of these mechanisms remain poorly understood, as few studies have evaluated their importance relative to environmental conditions and soil decomposers when assessing different processes during decomposition (e.g. C dynamics and N transformations).

We measured litter C and N losses during decomposition in 10 litter mixtures and calculated community‐weighted means (CWM) and dissimilarity (Rao's Q) of 13 litter traits as metrics of the mass‐ratio and niche complementarity mechanisms respectively. The 10 litter mixtures were incubated along a regional gradient (10 sites) in southern France over a year, where local environmental conditions (climate and soil parameters), and soil decomposers (microbes, nematodes, and macrofauna) were considered as drivers of decomposition.

Sites and litter mixtures represented a wide range of environmental conditions, decomposers, and litter diversity. Litter mixture was the major factor affecting litter C and N loss. N was immobilized during the early decomposition stages (up to c. 40% mass loss), especially in mixtures of low N concentrations. Litter CWM traits were the key drivers of litter C and N loss, but litter trait dissimilarity emerged as a major driver of litter N loss. Macrofauna played a significant role on C and N loss, but environmental conditions exerted a minor influence.

Our results highlight that distinct aspects of trait diversity in mixed species litter can play a more important role than environmental conditions and decomposers, which can affect the cycling of litter C and N at regional scales. Rather than opposing mass‐ratio and niche complementarity mechanisms, our study shows that both can play a critical role simultaneously in litter decomposition.

Synthesis. Our study emphasizes that, in the current context of global biodiversity decline, the mass‐ratio and niche complementarity mechanisms should be considered to assess litter decomposition dynamics under global change. As litter diversity mechanisms distinctly affected the cycling of C and N, we recommend taking into account such element‐specific effects to improve the prediction of the impacts of biodiversity change on biogeochemical cycles.
The microtubule end‐binding protein FgEB1 regulates polar growth and fungicide sensitivity via different interactors in Fusarium graminearum
Authors: Liu Zunyong , Wu Sisi , Chen Yun , Han Xinyue , Gu Qin , Yin Yanni , Ma Zhonghua 
Published: December 2016

SummaryIn yeasts, the end‐binding protein 1 (EB1) homologs regulate microtubule dynamics, cell polarization, and chromosome stability. However, functions of EB1 orthologs in plant pathogenic fungi have not been characterized yet. Here, we observed that the FgEB1 deletion mutant (ΔFgEB1) of Fusarium graminearum exhibits twisted hyphae, increased hyphal branching and curved conidia, indicating that FgEB1 is involved in the regulation of cellular polarity. Microscopic examination further showed that the microtubules of ΔFgEB1 exhibited less organized in comparison with those of the wild type. In addition, the lack of FgEB1 also altered the distribution of polarity‐related class I myosin via the interaction with the actin. On the other hand, we identified four core septins as FgEB1‐interacting proteins, and found that FgEB1 and septins regulated conidial polar growth in the opposite orientation. Interestingly, FgEB1 and FgKar9 constituted another complex that modulated the response to carbendazim, a microtubule‐damaging agent specifically. In addition, the deletion of FgEB1 led to dramatically decreased deoxynivalenol (DON) biosynthesis. Taken together, results of this study indicate that FgEB1 regulates cellular polarity, fungicide sensitivity and DON biosynthesis via different interactors in F. graminarum, which provides a novel insight into understanding of the biological functions of EB1 in filamentous fungi.
On‐site test to detect syphilis in pregnancy: a systematic review of test accuracy studies
Authors: Rogozińska E , Kara‐Newton L , Zamora JR , Khan KS 
Published: December 2016

BackgroundSyphilis in pregnancy can lead to fetal and neonatal death or congenital anomalies. Accurate on‐site tests are an essential part of effective prevention of mother‐to‐child transmission of the disease.ObjectiveThis systematic review assessed the accuracy of on‐site tests to detect infection with Treponema pallidum in pregnant women.Search strategyMajor databases were searched from inception to January 2016 using terms: ‘pregnancy’, ‘antenatal’, ‘syphilis’, ‘Treponema pallidum’ with their variations, and the search limit for the relevant study design.Selection criteriaWe included studies that used dual reference standard (non‐treponemal and treponemal tests) to detected syphilis in pregnancy.Data collection and analysisExtracted accuracy data were tabulated and pooled using hierarchical, bivariate random effects model.Main resultsSeven studies (combined sample 17 546) reporting the accuracy of four on‐site tests met the eligibility criteria. On average, Determine™ and SD BioLine Syphilis 3.0 had the highest sensitivity of all the evaluated tests: 0.83 (95% CI 0.58, 0.98) and 0.86 (95% CI 0.82, 0.89), respectively, with a high specificity 0.96 (95% CI 0.89, 1.00) and 0.99 (95% CI 0.94, 1.00), respectively. The Qualitative Rapid Plasma Reagin card commonly used in clinical practice had a pooled sensitivity of 0.70 (95% CI 0.54, 0.88) and specificity of 0.97 (95% CI 0.96, 0.99).ConclusionImmunochromatographic tests such as Determine™ and SD BioLine Syphilis 3.0 seem to be acceptable options in antenatal testing for syphilis, especially in resource‐limited settings. Future research should seek more evidence to strengthen this claim.Tweetable abstractOn‐site test to detect syphilis—options during antenatal care.
Employee development and voluntary turnover: testing the employability paradox
Authors: Nelissen Jill , Forrier Anneleen , Verbruggen Marijke 
Published: December 2016

AbstractThe employability paradox is a concern among employers. It states that development activities enhancing employees' employability also increase the risk for employee turnover. This study examined this paradox and probed the relationship between six development activities and voluntary turnover mediated by perceived employability. We tested both a turnover‐stimulating path via perceived external employability (i.e. perceived job alternatives with other employers) and a retention path via perceived internal employability (i.e. perceived job alternatives with the current employer) by using two‐wave longitudinal data from 588 employees. The results put the turnover risk into perspective: only upward job transition positively influenced turnover via perceived external employability. Also, the retention path via perceived internal employability was not supported: several development activities were positively related with perceived internal employability, but perceived internal employability did not influence turnover. We did, however, find a direct retention effect of skill utilisation. Overall, the results downplay the employability paradox.
A Randomized Trial Evaluating Whether Topiramate Aids Smoking Cessation and Prevents Alcohol Relapse in Recovering Alcohol‐Dependent Men
Authors: Anthenelli Robert M. , Heffner Jaimee L. , Wong Esther , Tibbs Jessie , Russell Katie , Isgro Melodie , Dinh Elizabeth , Wehrle Chris , Worley Matthew J. , Doran Neal 
Published: December 2016

BackgroundAlcohol and nicotine dependence frequently co‐occur, and quitting smoking might enhance long‐term alcohol abstinence. Topiramate appears to help non‐alcohol‐dependent individuals quit smoking, and our pilot work suggested efficacy only in men. It also prevents relapse to alcohol in recently detoxified alcoholics. We evaluated topiramate in abstinent alcohol‐dependent men to assess whether this medication (i) promotes smoking cessation and (ii) prevents alcohol and other drug relapse in the context of smoking cessation treatment.MethodsOne hundred and twenty‐nine alcohol‐abstinent (mean ~6 months) alcohol‐dependent male smokers (80% with other substance use disorders) participated in this 12‐week randomized, double blind, parallel group comparison of topiramate (up to 200 mg/d) and placebo with a 24‐week nontreatment follow‐up period. The study was carried out sequentially at 2 academic centers in the Midwest and Southern California between March 23, 2009 and November 20, 2014. All participants received manual‐guided smoking cessation counseling combined with medication‐focused compliance enhancement therapy. Randomization was block designed by the research pharmacist in a 1:1 ratio. Participants, investigators, and research personnel were masked to treatment assignment. The primary smoking end point was biochemically confirmed 4‐week continuous abstinence from smoking during weeks 9 to 12, while the secondary end point was relapse to any drinking or drug use during the entire 36‐week evaluation period. Logistic regression was used to determine the effects of topiramate on quitting smoking and alcohol relapse, controlling for relevant covariates. The trial is registered at ClinicalTrials.gov (number NCT00802412) and is now closed.ResultsOnly a small proportion (7.9%) of topiramate‐treated participants were able to quit smoking, and this cessation rate was similar to placebo (10.6%; odds ratio = 1.60; 95% confidence interval 0.4, 6.5; p = 0.51). Roughly 30% of the sample had a documented relapse to drinking or drug use during the study, and these rates were similar in the topiramate (20/63; 31.8%) and placebo groups (18/66; 27.3%; p = 0.58). Results of a longitudinal logistic regression model examining time to any alcohol relapse revealed no medication effect.ConclusionsTopiramate at a daily dosage of up to 200 mg per day, combined with smoking cessation and medication adherence counseling, had no effects on smoking cessation or the prevention of alcohol or drug relapse in male smokers who were in early or sustained full remission from alcohol and motivated to make a quit attempt. Alternative approaches for treating this high‐risk, dually dependent population are needed.