bluuebunny/crossref_metadata_2025_split huggingface dataset:
Nutrient stoichiometry and land use rather than species richness determine plant functional diversity
Authors: Busch Verena , Klaus Valentin H. , Penone Caterina , Schäfer Deborah , Boch Steffen , Prati Daniel , Müller Jörg , Socher Stephanie A. , Niinemets Ülo , Peñuelas Josep , Hölzel Norbert , Fischer Markus , Kleinebecker Till 
Published: December 2017

AbstractPlant functional traits reflect individual and community ecological strategies. They allow the detection of directional changes in community dynamics and ecosystemic processes, being an additional tool to assess biodiversity than species richness. Analysis of functional patterns in plant communities provides mechanistic insight into biodiversity alterations due to anthropogenic activity. Although studies have consi‐dered of either anthropogenic management or nutrient availability on functional traits in temperate grasslands, studies combining effects of both drivers are scarce. Here, we assessed the impacts of management intensity (fertilization, mowing, grazing), nutrient stoichiometry (C, N, P, K), and vegetation composition on community‐weighted means (CWMs) and functional diversity (Rao's Q) from seven plant traits in 150 grasslands in three regions in Germany, using data of 6 years. Land use and nutrient stoichiometry accounted for larger proportions of model variance of CWM and Rao's Q than species richness and productivity. Grazing affected all analyzed trait groups; fertilization and mowing only impacted generative traits. Grazing was clearly associated with nutrient retention strategies, that is, investing in durable structures and production of fewer, less variable seed. Phenological variability was increased. Fertilization and mowing decreased seed number/mass variability, indicating competition‐related effects. Impacts of nutrient stoichiometry on trait syndromes varied. Nutrient limitation (large N:P, C:N ratios) promoted species with conservative strategies, that is, investment in durable plant structures rather than fast growth, fewer seed, and delayed flowering onset. In contrast to seed mass, leaf‐economics variability was reduced under P shortage. Species diversity was positively associated with the variability of generative traits. Synthesis. Here, land use, nutrient availability, species richness, and plant functional strategies have been shown to interact complexly, driving community composition, and vegetation responses to management intensity. We suggest that deeper understanding of underlying mechanisms shaping community assembly and biodiversity will require analyzing all these parameters.
Sap flow characteristics and responses to summer rainfall for Pinus tabulaeformis and Hippophae rhamnoides in the Loess hilly region of China
Authors: Wu Xu , Tang Yakun , Chen Yunming , Wen Jie , Xie Yuli , Lu Senbao 
Published: December 2017

AbstractAs a major driving element of the structure and function of arid and semiarid ecosystems, rainfall is the essential factor limiting plant biological processes. To clarify the characteristics of transpiration and responses to summer rainfall, sap flow density (Fd) of Pinus tabulaeformis and Hippophae rhamnoides was monitored using thermal dissipation probes. In addition, midday leaf water potential (ψm) and leaf stomatal conductance (Gs) were also analyzed to determine water use strategies. The results indicated that the diurnal variation in the normalized Fd values exhibited a single‐peak curve for P. tabulaeformis, while H. rhamnoides showed multiple peaks. The normalized Fd for P. tabulaeformis remained relatively stable regardless of rainfall events. However, there was also a significant increase in the normalized Fd for H. rhamnoides in response to rainfall in June and August (p < .05), although no significant differences were observed in July. The normalized Fd values for P. tabulaeformis and H. rhamnoides fitted well with the derived variable of transpiration, an integrated index calculated from the vapor pressure deficit and solar radiation (Rs), using an exponential saturation function. The differences in fitting coefficients suggested that H. rhamnoides showed more sensitivity to summer rainfall (p < .01) than P. tabulaeformis. Furthermore, during the study period, P. tabulaeformis reduced Gs as soil water decreased, maintaining a relatively constant ψm; while H. rhamnoides allowed large fluctuations in ψm to maintain Gs. Therefore, P. tabulaeformis and H. rhamnoides should be considered isohydric and anisohydric species, respectively. And more consideration should be taken for H. rhamnoides in the afforestation activities and the local plantation management under the context of the frequently seasonal drought in the loess hilly region.
Silicon amendment to rice plants contributes to reduced feeding in a phloem‐sucking insect through modulation of callose deposition
Authors: Yang Lang , Li Pei , Li Fei , Ali Shahbaz , Sun Xiaoqin , Hou Maolin 
Published: December 2017

AbstractSilicon (Si) uptake by Poaceae plants has beneficial effects on herbivore defense. Increased plant physical barrier and altered herbivorous feeding behaviors are documented to reduce herbivorous arthropod feeding and contribute to enhanced plant defense. Here, we show that Si amendment to rice (Oryza sativa) plants contributes to reduced feeding in a phloem feeder, the brown planthopper (Nilaparvata lugens, BPH), through modulation of callose deposition. We associated the temporal dynamics of BPH feeding with callose deposition on sieve plates and further with callose synthase and hydrolase gene expression in plants amended with Si. Biological assays revealed that BPH feeding was lower in Si‐amended than in nonamended plants in the early stages post‐BPH infestation. Histological observation showed that BPH infestation triggered fast and strong callose deposition in Si‐amended plants compared with nonamended plants. Analysis using qRT‐PCR revealed that expression of the callose synthase gene OsGSL1 was up‐regulated more and that the callose hydrolase (β‐1,3‐glucanase) gene Gns5 was up‐regulated less in Si‐amended than in nonamended plants during the initial stages of BPH infestation. These dynamic expression levels of OsGSL1 and Gns5 in response to BPH infestation correspond to callose deposition patterns in Si‐amended versus nonamended plants. It is demonstrated here that BPH infestation triggers differential gene expression associated with callose synthesis and hydrolysis in Si‐amended and nonamended rice plants, which allows callose to be deposited more on sieve tubes and sieve tube occlusions to be maintained more thus contributing to reduced BPH feeding on Si‐amended plants.
Early phenology and growth trait variation in closely related European pine species
Authors: Wachowiak Witold , Perry Annika , Donnelly Kevin , Cavers Stephen 
Published: December 2017

AbstractClosely related taxa occupying different environments are valuable systems for studying evolution. In this study, we examined differences in early phenology (bud set, bud burst) and early growth in a common garden trial of closely related pine species: Pinus sylvestris, P. mugo, and P. uncinata. Seeds for the trial were sourced from populations across the ranges of each species in Europe. Over first 4 years of development, clear differences were observed between species, while the most significant intraspecific differentiation was observed among plants from P. sylvestris populations from continental European locations. Trait differences within P. sylvestris were highly correlated with altitude and latitude of the site of origin. Meanwhile, P. mugo populations from the Carpathians had the earliest bud set and bud flush compared to other populations of the species. Overall, populations from the P. mugo complex from heterogeneous mountain environments and P. sylvestris from the Scottish Highlands showed the highest within‐population variation for the focal traits. Although the three species have been shown to be genetically highly similar, this study reveals large differences in key adaptive traits both among and within species.
A Study for Sensitivity Improvement of 3‐D Lab‐on‐a‐CD‐Based Immunosensor
Authors: KATAOKA CHIWA , AZETA TSUKASA , SAWADAISHI KAZUYUKI , UKITA YOSHIAKI , YAMAGUCHI AKINOBU , UTSUMI YUICHI 
Published: December 2017

SUMMARYWe have developed a three‐dimensional (3D) Lab‐on‐a‐CD immunosensor based on a competitive/noncompetitive assay for small endocrine disruptors and biomolecules. To improve the sensitivity of the 3D Lab‐on‐a‐CD immunosensor, an immobilizing method of capturing‐type antibody on the sensor surface was investigated. The method is based on the introduction of a highly reactive amino group to a P(MMA/CEMA) copolymer surface having chlorine, and utilizing a biotin‐streptavidin system. The functionality of the 3D Lab‐on‐a‐CD immunosensor was evaluated by measuring mouse IgG. The detection limit was found to be 3 f g/assay (3 × 10‐12 g/assay). After further modification, the 3D Lab‐on‐a‐CD immunosensor, having some characteristics such as a substrate with highly integrated antibodies, is expected to be applicable for highly sensitive immunoassay.
Fitness consequences of occasional outcrossing in a functionally asexual plant (Oenothera biennis)
Authors: Maron John L. , Johnson Marc T. J. , Hastings Amy P. , Agrawal Anurag A. 
Published: December 2017

AbstractMany clonal organisms occasionally outcross, but the long‐term consequences of such infrequent events are often unknown. During five years, representing three to five plant generations, we followed 16 experimental field populations of the forb, Oenothera biennis, originally planted with the same 18 original genotypes. Oenothera biennis usually self fertilizes, which, due to its genetic system (permanent translocation heterozygosity), results in seeds that are clones of the maternal plant. However, rare outcrossing produces genetically novel offspring (but without recombination or increased heterozygosity). We sought to understand whether novel genotypes produced through natural outcrossing had greater fecundity or different multigenerational dynamics compared to our original genotypes. We further assessed whether any differences in fitness or abundances through time between original and novel genotypes were exaggerated in the presence vs. absence of insect herbivores. Over the course of the experiment, we genotyped >12,500 plants using microsatellite DNA markers to identify and track the frequency of specific genotypes and estimated fecundity on a subset (>3,000) of plants. The effective outcrossing rate was 7.3% in the first year and ultimately 50% of the plants were of outcrossed origin by the final year of the experiment. Lifetime fruit production per plant was on average 32% higher across all novel genotypes produced via outcrossing compared to the original genotypes, and this fecundity advantage was significantly enhanced in populations lacking herbivores. Among 43 novel genotypes that were abundant enough to phenotype with replication, plants produced nearly 30% more fruits than the average of their specific two parental genotypes, and marginally more fruits (8%) than their most fecund parent. Mean per capita fecundity of novel genotypes predicted their relative frequencies at the end of the experiment. Novel genotypes increased more dramatically in herbivore‐present compared to suppressed populations (45% vs. 27% of all plants), countering the increased competition from dandelions (Taraxacum officinale) that resulted from herbivore suppression. Increased interspecific competition likely also lead to the lower realized fitness of novel vs. original genotypes in herbivore‐suppressed populations. These results demonstrate that rare outcrossing and the generation of novel genotypes can create high‐fecundity progeny, with the biotic environment influencing the dynamical outcome of such advantages.
Growing competitive or tolerant? Significance of apical dominance in the overcompensating herb Gentianella campestris
Authors: Lennartsson Tommy , Ramula Satu , Tuomi Juha 
Published: December 2017

AbstractAs a compensatory response to herbivory, plants may branch vigorously when the growth of dormant meristems is triggered by shoot damage. Undamaged plants, on the other hand, often restrain branching, and this limitation on growth can be considered a cost of tolerance to herbivory. Restrained branching is caused by apical dominance and may, alternatively, be associated with fitness benefits in competitive environments that favor fast vertical growth. To test these hypotheses regarding selection for restrained branching, we compared the performance of two subspecies of the biennial grassland herb Gentianella campestris; the tall, apically dominant ssp. campestris and the short, multi‐stemmed ssp. islandica, which shows reduced apical dominance. For both subspecies, we manipulated the height of surrounding vegetation (competition) and damage intensity in grasslands of differing productivity (high, medium, low), and examined population growth rates using matrix population models combined with life table response experiments. In the absence of damage, ssp. campestris exhibited a higher population growth rate than ssp. islandica in the tallest vegetation, however with the growth rate still being below one. In the medium and low productivity environments where the vegetation was shorter, the population growth rate of ssp. islandica was considerably higher than that of ssp. campestris as long as no more than about 50% of the plants were damaged. When plants were damaged, the apically dominant ssp. campestris showed a positive population growth rate (λ > 1) and often overcompensatory seed production in all productivity levels, while ssp. islandica showed no compensation and therefore the population was predicted to decline (λ < 1). We conclude that restrained branching in Gentianella cannot be selected for by competition alone, but that episodes of apical damage are required to maintain the trait. Furthermore, because of the costs of restrained branching, apical dominance should be selected against in grasslands where competition and disturbance are low.
Permanent earthquake‐induced actions in buried pipelines: Numerical modeling and experimental verification
Authors: Sarvanis Gregory C. , Karamanos Spyros A. , Vazouras Polynikis , Mecozzi Elisabetta , Lucci Antonio , Dakoulas Panos 
Published: December 2017

SummaryBuried pipelines are often constructed in seismic and other geohazard areas, where severe ground deformations may induce severe strains in the pipeline. Calculation of those strains is essential for assessing pipeline integrity, and therefore, the development of efficient models accounting for soil‐pipe interaction is required. The present paper is aiming at developing efficient tools for calculating ground‐induced deformation on buried pipelines, often triggered by earthquake action, in the form of fault rupture, liquefaction‐induced lateral spreading, soil subsidence, or landslide. Soil‐pipe interaction is investigated by using advanced numerical tools, which employ solid elements for the soil, shell elements for the pipe, and account for soil‐pipe interaction, supported by large‐scale experiments. Soil‐pipe interaction in axial and transverse directions is evaluated first, using results from special‐purpose experiments and finite element simulations. The comparison between experimental and numerical results offers valuable information on key material parameters, necessary for accurate simulation of soil‐pipe interaction. Furthermore, reference is made to relevant provisions of design recommendations. Using the finite element models, calibrated from these experiments, pipeline performance at seismic‐fault crossings is analyzed, emphasizing on soil‐pipe interaction effects in the axial direction. The second part refers to full‐scale experiments, performed on a unique testing device. These experiments are modeled with the finite element tools to verify their efficiency in simulating soil‐pipe response under landslide or strike‐slip fault movement. The large‐scale experimental results compare very well with the numerical predictions, verifying the capability of the finite element models for accurate prediction of pipeline response under permanent earthquake‐induced ground deformations.
An Exploratory Study of Teaching Tasks in English as a Foreign Language Education
Authors: Turkan Sultan , Timpe-Laughlin Veronika , Papageorgiou Spiros 
Published: December 2017

AbstractDue to rising demand for qualified teachers of English as a foreign language (EFL), interest in issues pertaining to the language proficiency of these teachers has increased. However, research focusing on the teaching tasks that EFL teachers engage in for the purposes of EFL instruction is scant. The present study aims to address this gap in the literature by identifying the teaching tasks and exploring the teaching practices reported in logs kept by 5 EFL teachers over the course of a 2‐week period. Findings suggest that the majority of language teaching tasks observed in the teachers' logs were related to the instructional stages of (a) presenting subject material and communicating lesson content and (b) planning, developing, and organizing instruction.
Self‐perceptions of aging mediate the longitudinal relationship of hopelessness and depressive symptoms
Authors: Gum Amber M. , Ayalon Liat 
Published: December 2017

ObjectivesThe purpose of the current study was to examine the hypothesis that the prospective relationship between hopelessness and depressive symptoms is mediated by self‐perceptions of aging.MethodsData from 3 waves of the US Health and Retirement Study (2008, 2012, and 2014) were used (N = 4606; age M = 65.3, 55.5% female). In mediation analyses, hopelessness in 2008 was the independent variable, self‐perceptions of aging in 2012 were the mediator, and depressive symptoms in 2014 were the outcome variable.ResultsAfter controlling for covariates, hopelessness in 2008 was an independent predictor of self‐perceptions of aging in 2012 (β = −.10, P < .001), and self‐perceptions of aging in 2012 was an independent predictor of depressive symptoms in 2014 (β = −.41, P < .001). Hopelessness in 2008 showed both direct (β = .09, P < .001) and indirect (β = .03, P < .001) effects on depressive symptoms in 2014, indicating partial mediation by change in self‐perceptions of aging.ConclusionsAs hypothesized, change in self‐perceptions of aging partially mediated the relationship of hopelessness with depressive symptoms 6 years later. Findings are consistent with a conceptualization of hopelessness as broad negative expectations about the future that may contribute to negative self‐perceptions of aging and subsequent changes in depressive symptoms. Reducing hopelessness, increasing hope, and improving self‐perceptions of aging have potential to reduce and prevent depressive symptoms for older adults. Future research should examine the mechanisms of these interrelationships and other aging outcomes.
Factors affecting operative time in robotic thyroidectomy
Authors: Song Chang Myeon , Jang Youn Il , Ji Yong Bae , Park Jeong Seon , Kim Dong Sun , Tae Kyung 
Published: December 2017

AbstractBackgroundThe purpose of this study was to evaluate factors related to operative time in robotic thyroidectomy.MethodsWe retrospectively analyzed 240 patients who underwent robotic thyroidectomy. The total thyroidectomy cases and lobectomy cases were both categorized into those with long operative times (LOTs; upper 25% of cases) and those with short operative times (SOTs; lower 25%).ResultsAmong the total thyroidectomy cases, body mass index (BMI) ≥23 kg/m2 (hazard ratio [HR] 5.34; P = .008) and bilateral central neck dissection (CND; HR 14.92; P = .028) were more frequent in the LOT group in multivariate analysis. Among the lobectomy cases, BMI ≥23 kg/m2 (HR 12.92; P = .003) and unilateral CND (HR 21.38; P = .017) were the only independent risk factors for prolonged operative time.ConclusionBody habitus and clinical nodal status in the central compartment should be considered in deciding the indications for robotic thyroidectomy.
Numerical Evaluation of the Effects of Increasing Ratio of Cropped to Uncropped Width on Dry Drainage Efficiency in Salty Soils
Authors: Soltani Masoud , Rahimikhoob Ali , Sotoodehnia Abbas , Mendicino Giuseppe , Akram Mojtaba , Senatore Alfonso 
Published: December 2017

AbstractSustainable agriculture can contribute to food security in arid and semi‐arid regions if soil salinity in the root zone is kept under control. Recently, experts have been concentrating their research towrds alternative and environmentally friendly solutions. In this study, dry drainage was evaluated as a sustainable and cost‐effective alternative technique, by means of both field experiments and a numeric approach based on the HYDRUS‐2D modelling environment. Results showed that soil salinity in the cropped area increased from the soil surface to the bottom, and soil salinity movement (transport direction) was from the cropped to uncropped area. Increasing the ratio of cropped to uncropped width led to an increase in soil salinity of the cropped root zone and lack of stabilization of salinity concentration. Results of modelling showed that there are no significant differences between observed and modelled data, even though HYDRUS‐2D simulated soil water content better than soil salinity. Averages of performance indices for simulated soil water content (SE = 0.08, NRMSE = 0.133) were better in comparison with simulated soil salinity (SE = 0.28, NRMSE = 0.262). Soil surface salinity in the cropped area increased 2.7 times (from 2.1 to 5.7 dS m−1) during the experiment for equal cropped to uncropped width (1 (cropped): 1 (uncropped)), and by increasing cropped width (2 (cropped): 1 (uncropped)) it increased 7.5 times (from 2.3 to 17.3 dS m−1). Copyright © 2017 John Wiley & Sons, Ltd.
Aberrant methylation of mutL homolog 1 is associated with increased risk of non‐small cell lung cancer
Authors: Hu Haochang , Chen Xiaoying , Zhou Cong , Li Bin , Yang Yong , Ying Xiuru , Mao Yiyi , Zhang Yihan , Zhong Jie , Dai Jie , Yu Hang , Wu Boyi , Li Xiaodong , Wang Tiangong , Duan Shiwei 
Published: December 2017

BackgroundNon‐small cell lung cancer (NSCLC) is a common malignant tumor. DNA hypermethylation in the promoter region has been served as a potential molecular marker for several tumors. The goal of the current study was to assess the diagnostic ability of mutL homolog 1 (MLH1) promoter methylation in NSCLC.MethodsA total of 111 NSCLC patients’ paired tissue samples were obtained to explore the association between MLH1 promoter methylation and NSCLC by methylation‐specific polymerase chain reaction (MSP) method. Public databases including The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were used to verify our findings.ResultsOur results showed a significantly higher MLH1 methylation frequency in tumor tissue samples than their paired adjacent tissues (P = .008). ROC curve indicated that MLH1MSP assay was a sensitive but not a specific method in the diagnosis for NSCLC (sensitivity = 0.964, specificity = 0.135, AUC = 0.550). And the association between the methylation level and clinical characteristics has no statistical significance. TCGA cohort evinced a higher methylation probability in tumor group compared with nontumor group (the mean β value: −0.449 [−0.467, −0.437] vs −0.466 [−0.472, −0.437], P = .011), which was consistent with our results. Meanwhile, an inverse correlation between MLH1 methylation and MLH1 expression was detected in TCGA and GEO databases.ConclusionsThe MSP method for MLH1 methylation was a sensitive but not a specific diagnostic method for NSCLC.