bluuebunny/crossref_metadata_2025_split huggingface dataset:
Ecosystem nitrogen retention is regulated by plant community trait interactions with nutrient status in an alpine meadow
Authors: Wang Fangping , Shi Guoxi , Nicholas Ostle , Yao Buqing , Ji Mingfei , Wang Wenying , Ma Zhen , Zhou Huakun , Zhao Xinquan 
Published: December 2017

Abstract

Biotic nitrogen (N) retention is an important ecosystem function in the context of ongoing land‐use intensification, N deposition and global warming. However, a paucity of experimental evidence limits understanding of how different plant community components influence N retention in terrestrial ecosystems.

In this investigation, we conducted a 15N labelling experiment to test how plant community properties, including plant species richness/diversity, dominance and functional traits, influence plant N uptake and retention under different nutrient availabilities. A 3‐year experiment examined the effects of adding N (10 g N m−2 year−1) and phosphorus (P) (5 g P m−2 year−1) to an alpine meadow on the Qinghai‐Tibetan Plateau.

Results show that 15N retention increased with the addition of N and P; the addition of P produced the largest increase of 15N retention in plant and soil N pools. Changes in soil nutrient conditions also facilitated different plant community controls on ecosystem N retention. Ecosystem 15N retention was influenced by species richness and root biomass in the control plots; whereas the N addition treatment showed an important effect of community‐weighted means (CWM) of specific leaf area, and plots with additional P recorded lower CWM of root nitrogen content (root N) and larger CWM root:shoot ratios as important determinants.

Synthesis. Ecosystem N retention was influenced by conservative and exploitative plant species and/or their traits under N deficient and abundant conditions, respectively, whereas species richness and community plant biomass were most influential under middle condition. The discovery of an interaction between plant community traits and nutrient biogeochemistry as a mechanism for ecosystem N retention offers a means to predict how vegetation in alpine meadow ecosystems will respond to expected global change.
The roots of the drought: Hydrology and water uptake strategies mediate forest‐wide demographic response to precipitation
Authors: Chitra‐Tarak Rutuja , Ruiz Laurent , Dattaraja Handanakere S. , Mohan Kumar M. S. , Riotte Jean , Suresh Hebbalalu S. , McMahon Sean M. , Sukumar Raman 
Published: December 2017

Abstract

Drought‐induced tree mortality is expected to increase globally due to climate change, with profound implications for forest composition, function and global climate feedbacks. How drought is experienced by different species is thought to depend fundamentally on where they access water vertically below‐ground, but this remains untracked so far due to the difficulty of measuring water availability at depths at which plants access water (few to several tens of metres), the broad temporal scales at which droughts at those depths unfold (seasonal to decadal), and the difficulty in linking these patterns to forest‐wide species‐specific demographic responses.

We address this problem through a new eco‐hydrological framework: we used a hydrological model to estimate below‐ground water availability by depth over a period of two decades that included a multi‐year drought. Given this water availability scenario and 20 year long‐records of species‐specific growth patterns, we inversely estimated the relative depths at which 12 common species in the forest accessed water via a model of water stress. Finally, we tested whether our estimates of species relative uptake depths predicted mortality in the multi‐year drought.

The hydrological model revealed clear below‐ground niches as precipitation was decoupled from water availability by depth at multi‐annual scale. Species partitioned the hydrological niche by diverging in their uptake depths and so in the same forest stand, different species experienced very different drought patterns, resulting in clear differences in species‐specific growth. Finally, species relative water uptake depths predicted species mortality patterns after the multi‐year drought. Species that our method ranked as relying on deeper water were the ones that had suffered from greater mortality, as the zone from which they access water took longer to recharge after depletion.

Synthesis. This research changes our understanding of how hydrological niches operate for trees, with a trade‐off between realized growth potential and survival under drought with decadal scale return time. The eco‐hydrological framework highlights the importance of species‐specific below‐ground strategies in predicting forest response to drought. Applying this framework more broadly may help us better understand species coexistence in diverse forest communities and improve mechanistic predictions of forests productivity and compositional change under future climate.
Growing numbers, growing influence? A comparative study of policy congruence between parliaments and citizens of immigrant origin
Authors: KROEBER CORINNA 
Published: December 2017

AbstractA large set of research argues that policy responsiveness towards excluded societal factions such as minorities of immigrant origin improves through the presence of group members in parliaments because they bring forward different perspectives during parliamentary debates. This article challenges the straightforwardness of this relationship by demonstrating that the ability of legislators with immigrant backgrounds to shift the parliamentary agenda closer to the ideal points of citizens of foreign descent is conditional on two factors. First, representatives of immigrant origin need incentives to cultivate a personal vote, and second, their overall proportion of parliamentary seats has to remain rather marginal to influence the policy positions of the majority of representatives. The article's findings thus stress the importance of studying the contextual factors that moderate the relationship between group belonging and the capacity to promote group interests. Empirical evidence from nine European Democracies between 2002 and 2014 substantiates this argument – so that the analysis constitutes the first cross‐country comparison in a research field that has so far been dominated by single country studies. By using policy congruence as a measure for responsiveness, this article shifts the focal point from individual representatives’ attempts to promote the interests of citizens with immigrant backgrounds towards effectiveness of these endeavours.
Biological Activities of Camelina and Sophia Seeds Phenolics: Inhibition of LDL Oxidation, DNA Damage, and Pancreatic Lipase and α‐Glucosidase Activities
Authors: Rahman Md. Jiaur , Ambigaipalan Priyatharini , Shahidi Fereidoon 
Published: December 2017

AbstractThe free, esterified and insoluble‐bound phenolics of defatted meals of camelina and sophia seeds were extracted using an ultrasonic‐assisted procedure and alkaline hydrolysis. The antioxidant activities of the extracts were evaluated using DPPH and hydroxyl radical scavenging assays as well as inhibition of bleaching of β‐carotene in an oil‐in‐water system. Moreover, inhibition activity against pancreatic lipase, α‐glucosidase, low density lipoprotein (LDL) oxidation and DNA damage induced by peroxyl and hydroxyl radicals were examined for all seed extracts using in vitro systems. The seed extracts of camelina and sophia not only showed significant antioxidant activity but also inhibited pancreatic lipase and α‐glucosidase activities effectively. These enzymes in the digestive tract are associated with lipid and carbohydrate digestion, respectively, and control obesity and blood glucose level in the human body. The findings of this work may provide supporting information that camelina and sophia meals may inhibit human LDL oxidation and DNA nicking caused by free radicals and upon consumption may also exert anti‐obesity and antidiabetic effects. However, further research is required to confirm these biological activities in vivo.Practical ApplicationThe seed phenolic extracts of camelina and sophia not only showed significant antioxidant activity but also effectively inhibited the activities of pancreatic lipase and α‐glucosidase. Thus, camelina and sophia seed meals may serve as nutritional ingredients with bioactive phenolics that show in vitro antioxidant and biological effects. However, further research is required to confirm these health effects in vivo.
Calorimetric Methods for Measuring Stability and Reusability of Membrane Immobilized Enzymes
Authors: Mason Marco , Scampicchio Matteo , Quinn Colette F. , Transtrum Mark K. , Baker Nicholas , Hansen Lee D. , Kenealey Jason D. 
Published: December 2017

AbstractThe aim of this work is to develop calorimetric methods for characterizing the activity and stability of membrane immobilized enzymes. Invertase immobilized on a nylon‐6 nanofiber membrane is used as a test case. The stability of both immobilized and free invertase activity was measured by spectrophotometry and isothermal titration calorimetry (ITC). Differential scanning calorimetry was used to measure the thermal stability of the structure and areal concentration of invertase on the membrane. This is the 1st demonstration that ITC can be used to determine activity and stability of an enzyme immobilized on a membrane. ITC and spectrophotometry show maximum activity of free and immobilized invertase at pH 4.5 and 45 to 55 °C. ITC determination of the activity as a function of temperature over an 8‐h period shows a similar decline of activity of both free and immobilized invertase at 55 °C.Practical ApplicationEnzyme‐catalyzed reactions occur in mild and environmentally friendly conditions, but are usually too costly to use in food manufacturing. When free enzymes are used, they are used once and replaced for each reaction, but enzymes immobilized on a solid support can be reused and have the additional advantage of being removed from the product. In this study, new calorimetric methods that are universally applicable to characterizing immobilized enzymes are used to determine the activity, stability, and reusability of invertase immobilized on a nanofiber support.
Hyperspectral Imaging in Tandem with R Statistics and Image Processing for Detection and Visualization of pH in Japanese Big Sausages Under Different Storage Conditions
Authors: Feng Chao‐Hui , Makino Yoshio , Yoshimura Masatoshi , Thuyet Dang Quoc , García‐Martín Juan Francisco 
Published: December 2017

AbstractThe potential of hyperspectral imaging with wavelengths of 380 to 1000 nm was used to determine the pH of cooked sausages after different storage conditions (4 °C for 1 d, 35 °C for 1, 3, and 5 d). The mean spectra of the sausages were extracted from the hyperspectral images and partial least squares regression (PLSR) model was developed to relate spectral profiles with the pH of the cooked sausages. Eleven important wavelengths were selected based on the regression coefficient values. The PLSR model established using the optimal wavelengths showed good precision being the prediction coefficient of determination (Rp2) 0.909 and the root mean square error of prediction 0.035. The prediction map for illustrating pH indices in sausages was for the first time developed by R statistics. The overall results suggested that hyperspectral imaging combined with PLSR and R statistics are capable to quantify and visualize the sausages pH evolution under different storage conditions.Practical ApplicationIn this paper, hyperspectral imaging is for the first time used to detect pH in cooked sausages using R statistics, which provides another useful information for the researchers who do not have the access to Matlab. Eleven optimal wavelengths were successfully selected, which were used for simplifying the PLSR model established based on the full wavelengths. This simplified model achieved a high Rp2 (0.909) and a low root mean square error of prediction (0.035), which can be useful for the design of multispectral imaging systems.
HMMoce: An R package for improved geolocation of archival‐tagged fishes using a hidden Markov method
Authors: Braun Camrin D. , Galuardi Benjamin , Thorrold Simon R. 
Published: December 2017

Abstract

Electronic tagging of marine fishes is commonly achieved with archival tags that rely on light levels and sea surface temperatures to retrospectively estimate movements. However, methodological issues associated with light‐level geolocation have constrained meaningful inference to species where it is possible to accurately estimate time of sunrise and sunset. Most studies have largely ignored the oceanographic profiles collected by the tag as a potential way to refine light‐level geolocation estimates.

Open‐source oceanographic measurements and outputs from high‐resolution models are increasingly available and accessible. Temperature and depth profiles recorded by electronic tags can be integrated with these empirical data and model outputs to construct likelihoods and improve geolocation estimates.

The R package HMMoce leverages available tag and oceanographic data to improve position estimates derived from electronic tags using a hidden Markov approach. We illustrate the use of the model and test its performance using example blue and mako shark archival tag data. Model results were validated using independent, known tracks and compared to results from other geolocation approaches.

HMMoce exhibited as much as six‐fold improvement in pointwise error as compared to traditional light‐level geolocation approaches. The results demonstrated the general applicability of HMMoce to marine animals, particularly those that do not frequent surface waters during crepuscular periods.
Abundance, diet and prey selection of arboreal lizards in a grazed tropical woodland
Authors: Nordberg Eric J. , Murray Paul , Alford Ross , Schwarzkopf Lin 
Published: December 2017

AbstractThe diet of predators is a critical determinant of their ecological effects. Small vertebrate predators of invertebrates are often characterized as diet generalists based on diet descriptions, but few studies examine prey availability to determine whether prey choice occurs. We studied the prey availability in relation to the diet of two common and abundant, but understudied small vertebrates: Gehyra dubia, an arboreal nocturnal gecko, and Cryptoblepharus australis, an arboreal diurnal skink. We sampled lizards in two major woodland habitat types, Reid River box (Eucalyptus brownii) and Silver‐leaf ironbark (Eucalyptus melanophloia) and among four cattle grazing regimes (ranging from moderate – heavy stocking). Cryptoblepharus australis were more abundant in the Silver‐leaf ironbark habitat, but there was no effect of grazing regime on their abundance. In contrast, G. dubia did not differ significantly in abundance in relation to habitat type, but were more abundant in paddocks with heavier stocking rates. We quantified invertebrate prey available to lizards in these habitats using defined‐area searches and light trapping. Invertebrate community composition did not differ significantly between the habitat types or among the four grazing regimes. Although G. dubia and C. australis both occupied the same microhabitats, they were temporally segregated based on their activity times. While both species are apparently habitat generalists, we found that G. dubia and C. australis are selective in their diets. Only half of the invertebrate groups available in the environment occurred in the diets of either lizard species. Both species positively selected Coleoptera (beetles), Araneae (spiders), and Scorpiones (scorpions), and they exhibited high dietary niche overlap (O = 0.97). We suggest the increased availability of the top three preferred prey groups (beetles, spiders, and scorpions) may contribute to the high abundances of G. dubia in heavily grazed areas.
Metabolism of 14C‐labelled pentagalloylglucose by Epirrita autumnata and Agriopis aurantiaria (Lepidoptera: Geometridae) and implications for the nutrition of geometrid defoliators
Authors: Salminen Juha‐Pekka 
Published: December 2017

AbstractThe metabolism of pentagalloylglucose, the immediate biosynthetic precursor of both ellagitannins and gallotannins, was investigated in larvae of two geometrid species, autumnal moth Epirrita autumnata and scarce umber Agriopis aurantiaria. The aim was to determine yet unknown metabolic patterns of the widely distributed hydrolysable tannins in these model lepidopteran species. Pentagalloylglucose was applied in [U‐14C]‐labelled, leaf‐painted form in the larval diet. During the 24 h experiment, the radioactivity was distributed between all larval fractions studied, e.g. hemolymph, gut, the rest of the body, CO2 exhaled and frass excreted. Detailed chemical analyses and subfractionation of the larval fractions revealed that both species significantly modified the structure of pentagalloylglucose; it was the main 14C‐active component in none of the larval fractions. E. autumnata and A. aurantiaria were able to partially hydrolyse pentagalloylglucose as evidenced by the presence of 14C‐labelled gallic acid in the gut and in frass. The production of 14CO2 by these two species showed that they were either able to liberate CO2 from the COOH moiety of gallic acid or that they were able to use some parts of the pentagalloylglucose even as an energy source. Also newly formed, not yet characterised tannin metabolites were detected especially in the gut, hemolymph and body samples, in both soluble and insoluble forms. These findings emphasise that the hydrolysable tannin metabolism in insects is much more complex than earlier speculated and that there is a great variation within and between insect species in their ability to metabolise these polyphenolic plant metabolites. All this should be taken into account especially in attempts trying to explain insect performance on a leaf diet solely by correlations with the foliar tannin levels: the metabolic fate of tannins might be more important determinant of insect performance than the ingested amount of tannins per se.
Shifting Bordering and Rescue Practices in the Central Mediterranean Sea, October 2013–October 2015
Authors: Garelli Glenda , Heller Charles , Pezzani Lorenzo , Tazzioli Martina 
Published: December 2017

AbstractThis counter‐mapping project illustrates the areas of intervention of different operations geared toward rescue and enforcement between 2013 and 2015, including the Italian Navy's “Mare Nostrum” search and rescue mission, the EU border agency Frontex's “Triton” enforcement operation, the humanitarian interventions of commercial vessels, and the action of civil‐society rescue vessels such as those operated by Médecins Sans Frontières (MSF—Doctors Without Borders). The project offers a spatial understanding of the Mediterranean border‐scape, the practices of rescue and enforcement that occur within it, and the risk of sea‐crossing at this particular moment. Through these maps, the Central Mediterranean Sea emerges as a striking laboratory from which novel legal arrangements, surveillance technologies, and institutional assemblages converge.
Nonparametric estimation of the dynamic range of music signals
Authors: Coretto Pietro , Giordano Francesco 
Published: December 2017

SummaryThe dynamic range is an important parameter which measures the spread of sound power, and for music signals it is a measure of recording quality. There are various descriptive measures of sound power, none of which has strong statistical foundations. We start from a nonparametric model for sound waves where an additive stochastic term has the role of catching transient energy. This component is recovered by a simple rate‐optimal kernel estimator that requires a single data‐driven tuning parameter. The distribution of its variance is approximated by a consistent random subsampling method that is able to cope with the massive size of the typical dataset. Based on the latter, we propose a statistic, and an estimation method that is able to represent the dynamic range concept consistently. The behaviour of the statistic is assessed based on a large numerical experiment where we simulate dynamic compression on a selection of real‐world music signals. Application of the method to real data also shows how the proposed method can predict subjective experts' opinions about the hifi quality of a recording.
Mental rotation and the human body: Children's inflexible use of embodiment mirrors that of adults
Authors: Krüger Markus , Ebersbach Mirjam 
Published: December 2017

Adults’ mental rotation performance with body‐like stimuli is enhanced if these stimuli are anatomically compatible with a human body, but decreased by anatomically incompatible stimuli. In this study, we investigated these effects for kindergartners and first‐graders: When asked to mentally rotate cube configurations attached with human body parts in an anatomically compatible way, allowing for the projection of a human body, children performed better than with pure cube combinations. By contrast, when body parts were attached in an anatomically incompatible way, disallowing the projection of a human body, children performed worse than with pure combinations. This experiment is of specific interest against the background of two different theoretical approaches concerning imagery and the motor system in development: One approach assumes an increasing integration of motor processes and imagery over time that enables older children and adults to requisition motor resources for imagery processes, while the other postulates that imagery stems from early sensorimotor processes in the first place, and is disentangled from it over time. The finding that children of the two age groups tested show exactly the same effects as adults when mentally rotating anatomically compatible and incompatible stimuli is interpreted in favour of the latter approach.
Statement of contribution

What is already known on this subject?

In mental rotation, adults perform better when rotating anatomically possible stimuli as compared to rotating standard cube combinations.

Performance is worse when rotating anatomically impossible stimuli.

What does this study add?

The present study shows that children's mental transformations mirror those of adults in these respects.

In case of the anatomically impossible stimuli, this highlights an inflexible use of embodiment in both age groups.

This is in line with the Piagetian assumption of imagery being based on sensorimotor processes.
Paradox Lost: The Disappearing Female Job Satisfaction Premium
Authors: Green Colin P. , Heywood John S. , Kler Parvinder , Leeves Gareth 
Published: December 2017

AbstractUsing the original data source of Clark, we show that over the last two decades the female satisfaction gap he documented has vanished. This reflects a strong secular decline in female job satisfaction. This decline happened both because younger women became less satisfied as they aged, and because new female workers entered with lower job satisfaction than their early 1990s peers. Decompositions make clear that the decline does not reflect changing job characteristics for women but rather their increasingly less favourable evaluation of job characteristics. These findings fit with the suggestion that women in the early 1990s had a gap between their labour market expectations and actual experience that has since closed and that the gender satisfaction gap has vanished as a consequence.