bluuebunny/crossref_metadata_2025_split huggingface dataset:
Land use legacy effects on woody vegetation in agricultural landscapes of south‐western Ethiopia
Authors: Shumi Girma , Schultner Jannik , Dorresteijn Ine , Rodrigues Patrícia , Hanspach Jan , Hylander Kristoffer , Senbeta Feyera , Fischer Joern 
Published: April 2018

AbstractAimPast land use legacy effects—extinction debts and immigration credits—might be particularly pronounced in regions characterized by complex and dynamic landscape change. The aim of this study was to evaluate how current woody plant species distribution, composition and richness related to historical and present land uses.LocationA smallholder farming landscape in south‐western Ethiopia.MethodsWe surveyed woody plants in 72 randomly selected 1‐ha sites in farmland and grouped them into forest specialist, generalist and pioneer species. First, we investigated woody plant composition and distribution using non‐metric multidimensional scaling. Second, we modelled species richness in response to historical and current distance from the forest edge. Third, we examined diameter class distributions of trees in recently converted vs. permanent farmland.ResultsHistorical distance was a primary driver of woody plant composition and distribution. Generalist and pioneer species richness increased with historical distance. Forest specialists, however, did not respond to historical distance. Only few old individuals of forest specialist species remained in both recently converted and permanent farmlands.Main conclusionsOur findings suggest that any possible extinction debt for forest specialist species in farmland at the landscape scale was rapidly paid off, possibly because farmers cleared large remnant trees. In contrast, we found substantial evidence of immigration credits in farmland for generalist and pioneer species. This suggests that long‐established farmland may have unrecognized conservation values, although apparently not for forest specialist species. We suggest that conservation policies in south‐western Ethiopia should recognize not only forests, but also the complementary value of the agricultural mosaic—similar to the case of European cultural landscapes. A possible future priority could be to better reintegrate forest species in the farmland mosaic.
Effect of metformin on plasma metabolite profile in the Copenhagen Insulin and Metformin Therapy (CIMT) trial
Authors: Safai N. , Suvitaival T. , Ali A. , Spégel P. , Al‐Majdoub M. , Carstensen B. , Vestergaard H. , Ridderstråle M. ,   the CIMT Trial Group
Published: April 2018

AbstractAimMetformin is the first‐line treatment for Type 2 diabetes. However, not all people benefit from this drug. Our aim was to investigate the effects of metformin on the plasma metabolome and whether the pretreatment metabolite profile can predict HbA1c outcome.MethodsPost hoc analysis of the Copenhagen Insulin and Metformin Therapy (CIMT) trial, a multicentre study from May 2008 to December 2012, was carried out. We used a non‐target method to analyse 87 plasma metabolites in participants with Type 2 diabetes (n = 370) who were randomized in a 1 : 1 ratio to 18 months of metformin or placebo treatment. Metabolites were measured by liquid chromatography–mass spectrometry at baseline and at 18‐month follow‐up and the data were analysed using a linear mixed‐effect model.ResultsAt baseline, participants who were on metformin before the trial (n = 312) had higher levels of leucine/isoleucine and five lysophosphatidylethanolamines (LPEs), and lower levels of carnitine and valine compared with metformin‐naïve participants (n = 58). At follow‐up, participants randomized to metformin (n = 188) had elevated levels of leucine/isoleucine and reduced carnitine, tyrosine and valine compared with placebo (n = 182). At baseline, participants on metformin treatment with the highest levels of carnitine C10:1 and leucine/isoleucine had the lowest HbA1c (P‐interaction = 0.02 and 0.03, respectively). This association was not significant with HbA1c at follow‐up.ConclusionsMetformin treatment is associated with decreased levels of valine, tyrosine and carnitine, and increased levels of leucine/isoleucine. None of the identified metabolites can predict the HbA1c‐lowering effect of metformin. Further studies of the association between metformin, carnitine and leucine/isoleucine are warranted.
Association between left atrial stiffness and aortic plaque thickness in hypertensive patients with stroke
Authors: Mahfouz Ragab A. , Galal Islam , Ghareb Mohamed S. , Abdelghafar Adel S. 
Published: April 2018

ObjectiveOur aim was to investigate the relation between left atrial stiffness (LASt) and thoracic aortic plaque thickness in hypertensive patients with stroke.MethodA total of 97 hypertensive patients were recruited (age: 59.2 ± 7.5 years), including 56 consecutive patients with undefined stroke and 41 age‐matched hypertensive patients without stroke. Left atrial strain and stiffness were measured using speckle tracking echo. Thoracic aortic plaque detection and evaluation was performed using transesophageal echocardiography.ResultsHypertensive patients with stroke, when compared with those without stroke, had a significantly higher LASt value (P < .001). The percentage of plaque 1–4 mm thickness were comparable in both groups (23.2% vs 21.9%; P > .05). While the percentage of plaque ≥4 mm thickness was much higher in hypertensive patients with stroke (71.4% vs 4.9%; P < .001). LASt was considerably increased in hypertensive group with paroxysmal atrial fibrillation (PAF) when compared to hypertensive group without PAF (P < .01). A significant positive correlation was found between the LASt and plaque thickness (P < .001). Multivariate analysis showed that LASt was the strongest independent predictor for ≥4 mm aortic plaque thickness (Hazard ratio = 6.153; P < .001). With receiver operating characteristic (ROC) curve analysis, LASt > 0.63 was the best cutoff value in predicting aortic plaque thickness ≥ 4 mm.ConclusionLeft atrial stiffness was significantly associated with aortic plaque thickness ≥ 4 mm, in hypertensive patients with stroke. These finding prevailed the importance of LASt in risk stratification of hypertension.
Co‐occurrence of defensive traits in the potato aphid Macrosiphum euphorbiae
Authors: Clarke Hannah V. , Foster Stephen P. , Oliphant Linda , Waters Ewan W. , Karley Alison J. 
Published: April 2018

1. Insecticide usage selects strongly for resistance in aphid populations, but this could entail fitness costs in other resistance traits. The potato aphid Macrosiphum euphorbiae Thomas exhibits intraspecific variation in susceptibility to parasitism by braconid wasps and provides a suitable species to study the relation between the defensive traits of parasitism and insecticide resistance.2. Clonal lines (23 in total) of M. euphorbiae were established from aphids collected in 2013 from geographically separate populations in the U.K. Clonal lines belonged to five aphid genotypes, but one genotype predominated (78% of samples), and the facultative endosymbiont Hamiltonella defensa was detected in c. 40% of lines.3. Total esterase activity in aphid tissues varied significantly between aphid genotypes and collection areas, but there was no clear pattern in relation to H. defensa infection or between collection sites likely to differ in insecticide pressures.4. Five clonal lines representing low to moderate levels of enzyme activity, which included different aphid genotypes and presence/absence of H. defensa infection, were assayed for their susceptibility to the parasitoid wasp Aphidius ervi Haliday. Aphid mummification varied significantly between aphid genotypes, with low values in one genotype of aphids irrespective of H. defensa presence.5. The results revealed that aphid lines belonging to the parasitism‐resistant genotype exhibited moderate levels of total esterase activity, indicating a competitve advantage for this genotype of M. euphorbiae when exposed to chemical and biological control factors in agroecosystems.
Big floods, big knowledge gap: Food web dynamics in a variable river system
Authors: Davis Aaron M. , Pusey Brad J. , Pearson Richard G. 
Published: April 2018

AbstractWhile flow regime is widely recognised as an over‐arching feature structuring aquatic ecosystems, the influence of flood events on feeding habits in fish assemblages inhabiting variable environments remains largely unknown. In this study, we investigated how diets of a fish assemblage changed in response to fluctuations in hydrology in a highly variable, wet‐dry tropical Australian river. We compared dietary habits, trophic guilds and intra‐ and interspecific dietary overlap and diet breadth across different seasons. Wet‐season floods acted as major geomorphic and ecological perturbations that exerted substantial effects on the trophic dynamics of the terapontid assemblage, particularly through the removal of in‐stream plant production and detritus. Forced by major shifts in food source availability due to seasonal flooding, fishes responded to these perturbations by marked changes in diet, with significant guild switching following wet‐season floods. Rather than the predictable, gradual, changes in consumer–resource interactions associated with the gentler seasonal flood pulse evident in other tropical river systems, study results instead emphasised rapid and profound changes to species' diets and trophic interactions following abrupt flood pulses. These sudden shifts in food sources may also explain some of the lack of clarity in discrimination of specific carbon sources or species' trophic levels evident in isotopic food web studies from the region. Results indicate that the effects of flood pulses on assemblage trophic interactions may differ among ecosystem types and across the broad potential scale of hydrological disturbance mediated by flood events.
Genomewide identification and development of microsatellite markers for Marssonina brunnea and their applications in two populations
Authors: Zhang Y. , He W. , Yan D.‐H. 
Published: April 2018

SummaryMarssonina brunnea is an important pathogen that causes Marssonina leaf spot disease of poplar (MLDP) in various poplar species. Resistance breeding is considered as the main method for preventing this disease and requires information on genetic diversity and population structure. However, molecular markers that may be utilized in the identification of this fungus are limited. This study investigated the distribution of microsatellites in the M. brunnea genome. A total of 15,356 microsatellite markers (excluding mononucleotide repeats) were isolated from 50.1 Mb of genomic sequence. Eight M. brunnea isolates were evaluated in terms of 102 loci, followed by the selection of markers that could be utilized in investigating the population structure of 47 M. brunnea isolates from two populations. Twenty‐four polymorphic microsatellite markers were developed for M. brunnea. The number of alleles per locus ranged from two to eight (average: 3.75). The polymorphism information content (PIC) of these loci ranged from 0.0408 to 0.6492. The average Shannon's information index of these loci in the two populations was 0.3819 and 0.5351, respectively. Using these markers, M. brunnea isolates were mainly divided into two distinct clusters based on the relatedness of the sampling sites. These results indicate that the selected markers could be effectively utilized in investigating the population genetic structure of M. brunnea. This is the first report on microsatellite markers in M. brunnea.
Nietzsche on guilt: Dependency, debt, and imperfection
Authors: Morrisson Iain 
Published: April 2018

AbstractIn this paper, I offer a new way of reading Nietzsche's second essay inOn the Genealogy of Morality. At the heart of my account is the claim that Nietzsche is primarily interested in a persistent or existential form of guilt in this essay and only concerned with locally reactive cases of guilt as a function of this deeper phenomenon. I argue that, for Nietzsche, this persistent form of guilt develops out of a deep feeling of indebtedness or owing that accompanies a fearful sense of dependency on the gods. When this sense of dependent indebtedness mixes with bad conscience, which arises through the shift from prehistoric tribes to state‐like communities, it becomes a moral problem; vast numbers of “slaves and serfs” (GM II.20) start to feel like they are not sufficiently honoring their dependent relationship with the gods. It is this feeling of persistent guilt that Nietzsche thinks metastasizes into Christian guilt.
Ictal connectivity in childhood absence epilepsy: Associations with outcome
Authors: Tenney Jeffrey R. , Kadis Darren S. , Agler William , Rozhkov Leonid , Altaye Mekibib , Xiang Jing , Vannest Jennifer , Glauser Tracy A. 
Published: April 2018

SummaryObjectiveThe understanding of childhood absence epilepsy (CAE) has been revolutionized over the past decade, but the biological mechanisms responsible for variable treatment outcomes are unknown. Our purpose in this prospective observational study was to determine how pretreatment ictal network pathways, defined using a combined electroencephalography (EEG)–functional magnetic resonance imaging (EEG‐fMRI) and magnetoencephalography (MEG) effective connectivity analysis, were related to treatment response.MethodsSixteen children with newly diagnosed and drug‐naive CAE had 31 typical absence seizures during EEG‐fMRI and 74 during MEG. The spatial extent of the pretreatment ictal network was defined using fMRI hemodynamic response with an event‐related independent component analysis (eICA). This spatially defined pretreatment ictal network supplied prior information for MEG‐effective connectivity analysis calculated using phase slope index (PSI). Treatment outcome was assessed 2 years following diagnosis and dichotomized to ethosuximide (ETX)–treatment responders (N = 11) or nonresponders (N = 5). Effective connectivity of the pretreatment ictal network was compared to the treatment response.ResultsPatterns of pretreatment connectivity demonstrated strongest connections in the thalamus and posterior brain regions (parietal, posterior cingulate, angular gyrus, precuneus, and occipital) at delta frequencies and the frontal cortices at gamma frequencies (P < .05). ETX treatment nonresponders had pretreatment connectivity, which was decreased in the precuneus region and increased in the frontal cortex compared to ETX responders (P < .05).SignificancePretreatment ictal connectivity differences in children with CAE were associated with response to antiepileptic treatment. This is a possible mechanism for the variable treatment response seen in patients sharing the same epilepsy syndrome.
Dawn singing of the Brownish‐flanked Bush Warbler influences dawn chorusing in a bird community
Authors: Xia Canwei , Lloyd Huw , Shi Jie , Wei Chentao , Zhang Yanyun 
Published: April 2018

AbstractDespite numerous studies on the function of the avian dawn chorus, few studies have examined whether dawn singing may influence the singing of other species. Here, we built on our previous study which found male Brownish‐flanked Bush Warblers (Horornis fortipes) increase their dawn singing intensity after conspecific playback on the previous day. We reanalyzed those recordings to quantify the start of dawn singing in other nine sympatric songbird species. Ranking‐scaling analyses identified a distinctive sequential pattern of dawn singing among these bird species between the first and the second dawn chorus, and meta‐analysis showed a significant trend to singing earlier in the bird community accompanied by the increase in dawn singing intensity in Brownish‐flanked Bush Warbler. Species with songs most similar to that of the Brownish‐flanked Bush Warbler and species that were phylogenetically distantly related to the Brownish‐flanked Bush Warbler showed a greater shift in the onset of dawn singing. Our study is one of the few studies showing how bird song influences heterospecific singing, and this may influence the temporal organization of song activity in the community, and result in synchronization in singing activities among different species, such as singing in dawn and dusk chorus.
Concentration‐dependent chemosensory responses towards pheromones are influenced by receiver attributes in Asian elephants
Authors: LaDue Chase A. , Goodwin Thomas E. , Schulte Bruce A. 
Published: April 2018

AbstractThe physical structure of a signal is not sufficient to determine its meaning. For chemical signals between conspecifics, this concept is termed “pheromonal parsimony.” The function of a compound depends not only on its molecular structure but also on its context, which can include signal concentration and various receiver attributes. We sought to investigate the contextual flexibility of chemosensory responses through bioassays with Asian elephant (Elephas maximus) sex pheromones of various concentrations (frontalin, from males, and (Z)‐7‐dodecenyl acetate [Z7‐12:Ac], from females). We hypothesized that elephants would respond stronger to higher concentrations, especially towards the opposite‐sex pheromone, and that receiver age and sexual experience would modify responses. We examined responses of 73 captive elephants to both compounds. Pheromone concentration impacted the rate of chemosensory response, which was further modified by the sex, age and/or sexual experience of the receiver. Response rates increased with concentration for each compound across both sexes. Experience shaped male responses with older, physiologically primed males responding more often. The interaction between experience and age affected female response to frontalin, but not toZ7‐12:Ac. Furthermore, response thresholds were modified by sexual experience in most cases: experienced animals generally had lower thresholds than inexperienced animals. Elephants responded to each solution according to its perceived relevance, including concentration. These results also indicate that receiver attributes (e.g., sex, age and sexual experience) may modify seemingly fixed chemosensory responses and further emphasize the flexibility of vertebrate communication systems.
Evaluating the effects of climate change in the southern Benguela upwelling system using the Atlantis modelling framework
Authors: Ortega‐Cisneros Kelly , Cochrane Kevern L. , Fulton Elizabeth A. , Gorton Rebecca , Popova Ekaterina 
Published: April 2018

AbstractThe ocean is affected by multiple anthropogenic stressors including climate change, the effects of which are already evident in many ocean ecosystems. The ABACuS v2 end‐to‐end model together with climate projections from the NEMO‐MEDUSA 2.0 model were used to evaluate the effects of fishing, warming and horizontal and vertical mixing on the southern Benguela upwelling system. Of the drivers examined in this study, warming had the greatest effect on species biomass, with mainly negative effects. The magnitude of the impacts of warming intensified from the RCP 2.6 to the 8.5 emission scenario. Fishing negatively affected demersal and large pelagic fish, which in turn resulted in a biomass increase of forage fish due to a decrease in predation pressure. Water mixing was found to have minor indirect effects on zooplankton biomass and fish. The responses of species and species groups to the combined effects of fishing and warming were approximately equally divided between additive, synergistic and antagonistic. Interpretation of our model results suggests that the southern Benguela system is likely to be affected by climate change, including substantial changes in the abundance of some species important to the region's fisheries. Future planning for fisheries needs to take this into account, including through management that strives to maintain the resilience of key species and the system as a whole. In line with previous studies on the southern Benguela, the results reinforce the importance of including consideration of the indirect and combined impacts of climate change and fishing in management and planning.
Mass coral bleaching causes biotic homogenization of reef fish assemblages
Authors: Richardson Laura E. , Graham Nicholas A. J. , Pratchett Morgan S. , Eurich Jacob G. , Hoey Andrew S. 
Published: April 2018

AbstractGlobal climate change is altering community composition across many ecosystems due to nonrandom species turnover, typically characterized by the loss of specialist species and increasing similarity of biological communities across spatial scales. As anthropogenic disturbances continue to alter species composition globally, there is a growing need to identify how species responses influence the establishment of distinct assemblages, such that management actions may be appropriately assigned. Here, we use trait‐based analyses to compare temporal changes in five complementary indices of reef fish assemblage structure among six taxonomically distinct coral reef habitats exposed to a system‐wide thermal stress event. Our results revealed increased taxonomic and functional similarity of previously distinct reef fish assemblages following mass coral bleaching, with changes characterized by subtle, but significant, shifts toward predominance of small‐bodied, algal‐farming habitat generalists. Furthermore, while the taxonomic or functional richness of fish assemblages did not change across all habitats, an increase in functional originality indicated an overall loss of functional redundancy. We also found that prebleaching coral composition better predicted changes in fish assemblage structure than the magnitude of coral loss. These results emphasize how measures of alpha diversity can mask important changes in the structure and functioning of ecosystems as assemblages reorganize. Our findings also highlight the role of coral species composition in structuring communities and influencing the diversity of responses of reef fishes to disturbance. As new coral species configurations emerge, their desirability will hinge upon the composition of associated species and their capacity to maintain key ecological processes in spite of ongoing disturbances.
High‐Q microwave ceramics of Li2TiO3 co‐doped with magnesium and niobium
Authors: Du Mingkun , Li Lingxia , Yu Shihui , Sun Zheng , Qiao Jianli 
Published: April 2018

AbstractIn order to solve the problems of acceptor/donor individual doping in Li2TiO3 system and clarify the superiority mechanism of co‐doping for improving the Q value, Mg + Nb co‐doped Li2TiO3 have been designed and sintered at a medium temperature of 1260°C. The effects of each Mg/Nb ion on structure, morphology, grain‐boundary resistance and microwave dielectric properties are investigated. The substitution of (Mg1/3Nb2/3)4+ inhibits not only the diffusion of Li+ and reduction in Ti4+, but also the formation of microcracks in ceramics, which promotes the enhancement of Q value. The experiments reveal that Q × f value of Li2TiO3 ceramics co‐doped with magnesium and niobium is 113 774 GHz (at 8.573 GHz), which is increased by 113% compared with the pure Li2TiO3 ceramics. And the co‐doped ceramics have an appropriate dielectric constant of 19.01 and a near‐zero resonance frequency temperature coefficient of 13.38 ppm/°C. These results offer a scientific basis for co‐doping in Li2TiO3 system, and the outstanding performance of (Mg + Nb) co‐doped ceramics provides a solid foundation for widespread applications of microwave substrates, resonators, filters and patch antennas in modern wireless communication equipments.