bluuebunny/crossref_metadata_2025_split huggingface dataset:
Generation of ϵ,ϵ‐Difluorinated Metal‐Pentadienyl Species through Lanthanide‐Mediated C−F Activation
Authors: Kumar Tarun , Massicot Fabien , Harakat Dominique , Chevreux Sylviane , Martinez Agathe , Bordolinska Klaudia , Preethalayam Preethanuj , Kokkuvayil Vasu Radhakrishnan , Behr Jean‐Bernard , Vasse Jean‐Luc , Jaroschik Florian 
Published: October 2017

AbstractHeavy metal on Lewis acid: The combination of lanthanide metals and AlCl3 has been employed for selective single C−F activation in benzofulvenes comprising an exocyclic CF3 substituent. Intermediate ϵ,ϵ‐difluorinated metal‐dienyl species react with a large variety of aldehydes in a highly regio‐ and diastereoselective fashion to afford 1,1‐disubstituted indenes bearing a difluorovinyl group. These new building blocks have been further transformed through a hydrogenation–cyclization process into fluorinated heterocyclic spiro compounds.
Neural stem/progenitor cells are activated during tail regeneration in the leopard gecko (Eublepharis macularius)
Authors: Gilbert E.A.B. , Vickaryous M.K. 
Published: October 2017

AbstractAs for many lizards, the leopard gecko (Eublepharis macularius) can self‐detach its tail to avoid predation and then regenerate a replacement. The replacement tail includes a regenerated spinal cord with a simple morphology: an ependymal layer surrounded by nerve tracts. We hypothesized that cells within the ependymal layer of the original spinal cord include populations of neural stem/progenitor cells (NSPCs) that contribute to the regenerated spinal cord. Prior to tail loss, we performed a bromodeoxyuridine pulse‐chase experiment and found that a subset of ependymal layer cells (ELCs) were label‐retaining after a 140‐day chase period. Next, we conducted a detailed spatiotemporal characterization of these cells before, during, and after tail regeneration. Our findings show that SOX2, a hallmark protein of NSPCs, is constitutively expressed by virtually all ELCs before, during, and after regeneration. We also found that during regeneration, ELCs express an expanded panel of NSPC and lineage‐restricted progenitor cell markers, including MSI‐1, SOX9, and TUJ1. Using electron microscopy, we determined that multiciliated, uniciliated, and biciliated cells are present, although the latter was only observed in regenerated spinal cords. Our results demonstrate that cells within the ependymal layer of the original, regenerating and fully regenerate spinal cord represent a heterogeneous population. These include radial glia comparable to Type E and Type B cells, and a neuronal‐like population of cerebrospinal fluid‐contacting cells. We propose that spinal cord regeneration in geckos represents a truncation of the restorative trajectory observed in some urodeles and teleosts, resulting in the formation of a structurally distinct replacement.
Where Does Electron Correlation Lie? Some Answers from a Real Space Partition
Authors: Casalz‐Sainz José Luis , Guevara‐Vela José Manuel , Francisco Evelio , Rocha‐Rinza Tomás , Martín Pendás Ángel 
Published: October 2017

AbstractWe discuss an intra‐ and interatomic partition of the electron correlation energy (Ecorr) within the interacting quantum atoms (IQA) approach at the accurate coupled cluster level with single, double, and estimated triple excitations (CCSDT(T)). This division offers a privileged window into the spatial localization of this component of the molecular energy. We show that the total molecularEcorris dominated by the intra‐atomic or intra‐fragment terms and that interatomic contributions change smoothly from short‐ to long‐range correlation (dispersion). The sign of these interatomic correlation terms differentiate between (i) mainly covalent or (ii) mainly ionic or nonbonded interactions. We propose that this feature may be used to define and examine intramolecular dispersion terms.
The computation and analysis of energy‐efficient multirelay and multihop communication scheme in wireless sensor networks
Authors: Xie Zhibin , Shen Qin , Hu Ying , Su Yinjie , Wang Yajun 
Published: October 2017

SummaryWireless sensor network (WSN) has been one of the most important network technologies nowadays. However, the communication of wireless sensor nodes is often constrained by computation capability and energy efficiency, and direct transmission is hard to adapt to all communication environments. Cooperative transmission can achieve the low energy consumption requirements effectively. But most researches considered multirelay and singular‐hop scheme, and their energy efficiencies were not satisfactory in a longer transmission distance. To address this problem, we investigate the effect of the relay links and the relay node hops on the energy consumption in this paper. By deriving the outage probability of the multirelay and multihop transmission scheme, the minimum transmitting power of the source node is obtained. Then the existence of the minimum energy consumption is proved with respect to the number of relay links. Simultaneously, to reduce the computational complexity to ensure the effective implementation of the communication, the optimal number of relay links is calculated based on the minimum energy consumption. The simulation results show that the proposed multirelay and multihop transmission scheme has better transmission efficiency and can achieve satisfactory performance of communication and computation cooperation.
Comparative responses of early‐successional plants to charcoal soil amendments
Authors: Gale Nigel V. , Halim Md Abdul , Horsburgh Mark , Thomas Sean C. 
Published: October 2017

AbstractCharcoal used as a soil amendment, or “biochar,” has received considerable recent research attention as a means to increase plant productivity while mitigating climate change through enhanced carbon sequestration. Interest in biochar for use in the restoration of disturbed sites is growing; however, biochar effects on wild plant species of the early phase of post‐disturbance succession have received almost no prior research attention. Physiological adaptations that enable rapid growth in early‐successional pioneers (e.g., high rates of photosynthesis) should be advantageous in soils with fresh charcoal since plants with a capacity for expeditious resource capture can capitalize on resource pulses from leachable mineral elements. In a glasshouse study, we tested the effects of biochar applied at two doses (10 and 20 t/ha) to brunisol/juvenile podzol soils, collected from a managed temperate mixed‐wood forest, on the growth and physiology of 13 herbaceous old‐field pioneers. We measured leaf‐level physiology and nutrient supply rates throughout the experiment, and biomass and reproductive performance at experiment completion. Overall, biochar treatments resulted in 30–37% increases in final average aboveground biomass, 13–17% increases in photosynthesis, and an average ~44% increase in leaf‐level water‐use efficiency (at 10 t/ha), but with a high species‐specific variation that included negative responses. We detected weak negative relationships between intrinsic photosynthetic rates (of non‐biochar controls) and some biomass responses: Species with high photosynthetic capacities tended to have low or negative biomass responses to biochar. Plants in biochar treatments flowered earlier and on average had double the reproductive biomass overall. Pulses of PO4− and K+ were supplied by biochar in the first four weeks of the experiment, while NO3− was significantly immobilized by biochar. These results suggest that by providing a pulse of P and base cations, biochar can improve the restoration of disturbed landscapes by enhancing the physiological and reproductive performance of a subset of pioneers that have moderate photosynthetic rates and nitrogen demand. Biochar has important potential applications to restoration; however, biochar is likely to affect community composition strongly, and careful consideration of the physiological rates and nitrogen requirements of target species will be necessary to maximize the success of biochar‐based restoration projects.
Non‐linear thresholds characterize the relationship between reef fishes and mangrove habitat
Authors: Shideler Geoffrey S. , Araújo Rafael J. , Walker Brian K. , Blondeau Jeremiah , Serafy Joseph E. 
Published: October 2017

AbstractA significant obstacle to evaluating the importance of mangrove habitat to coral reef fishes has been the difficulty of disentangling its effects from other subtidal/nearshore habitats or human population pressures. Florida's seascape, unlike most others, has been extensively surveyed and mapped, and there are reliable estimates of human population density. Despite many studies that have correlated reef fish abundance with nearby mangrove habitat, some researchers continue to question the importance of mangroves to reef fishes. Previous studies that have investigated the mangrove–reef fish subsidy effect have applied methods that either compared averages or examined linear relationships; yet there is a body of literature that indicates that the effects of habitat are characterized by thresholds and limiting functions. Here, we employed a generalized additive model to investigate whether species richness of 106 mangrove‐associated reef fishes is related to thresholds in the extent of nearby mangrove forests along the Florida Keys Reef Tract. In addition, we used linear discriminant analyses (LDAs) to examine the relationships between the occurrence of 77 reef fish species and extent of Florida mangrove forests. We found that after accounting for confounding factors, at scales <20 km2, species richness declines with decreasing mangrove extent, whereas richness increases with increasing mangrove extent at scales >80 km2. Results of our LDA suggested that at least 49 reef fish species (64% of focal species) were associated with higher nearby mangrove forest extent. Our results indicate that of all habitat attributes considered, mangroves played the most substantial role in the diversity of nearby reef fish populations. These apparent thresholds (i.e., non‐linearities) in the extent of mangrove forests should be incorporated into fisheries critical habitat management and emphasize the need to consider non‐linear relationships between fishes and their habitat.
Linear and nonlinear effects of temperature and precipitation on ecosystem properties in tidal saline wetlands
Authors: Feher Laura C. , Osland Michael J. , Griffith Kereen T. , Grace James B. , Howard Rebecca J. , Stagg Camille L. , Enwright Nicholas M. , Krauss Ken W. , Gabler Christopher A. , Day Richard H. , Rogers Kerrylee 
Published: October 2017

AbstractClimate greatly influences the structure and functioning of tidal saline wetland ecosystems. However, there is a need to better quantify the effects of climatic drivers on ecosystem properties, particularly near climate‐sensitive ecological transition zones. Here, we used climate‐ and literature‐derived ecological data from tidal saline wetlands to test hypotheses regarding the influence of climatic drivers (i.e., temperature and precipitation regimes) on the following six ecosystem properties: canopy height, biomass, productivity, decomposition, soil carbon density, and soil carbon accumulation. Our analyses quantify and elucidate linear and nonlinear effects of climatic drivers. We quantified positive linear relationships between temperature and above‐ground productivity and strong positive nonlinear (sigmoidal) relationships between (1) temperature and above‐ground biomass and canopy height and (2) precipitation and canopy height. Near temperature‐controlled mangrove range limits, small changes in temperature are expected to trigger comparatively large changes in biomass and canopy height, as mangrove forests grow, expand, and, in some cases, replace salt marshes. However, within these same transition zones, temperature‐induced changes in productivity are expected to be comparatively small. Interestingly, despite the significant above‐ground height, biomass, and productivity relationships across the tropical–temperate mangrove–marsh transition zone, the relationships between temperature and soil carbon density or soil carbon accumulation were not significant. Our literature review identifies several ecosystem properties and many regions of the world for which there are insufficient data to fully evaluate the influence of climatic drivers, and the identified data gaps can be used by scientists to guide future research. Our analyses indicate that near precipitation‐controlled transition zones, small changes in precipitation are expected to trigger comparatively large changes in canopy height. However, there are scant data to evaluate the influence of precipitation on other ecosystem properties. There is a need for more decomposition data across climatic gradients, and to advance understanding of the influence of changes in precipitation and freshwater availability, additional ecological data are needed from tidal saline wetlands in arid climates. Collectively, our results can help scientists and managers better anticipate the linear and nonlinear ecological consequences of climate change for coastal wetlands.
Model parameters for representative wetland plant functional groups
Authors: Williams Amber S. , Kiniry James R. , Mushet David , Smith Loren M. , McMurry Scott , Attebury Kelly , Lang Megan , McCarty Gregory W. , Shaffer Jill A. , Effland William R. , Johnson Mari‐Vaughn V. 
Published: October 2017

AbstractWetlands provide a wide variety of ecosystem services including water quality remediation, biodiversity refugia, groundwater recharge, and floodwater storage. Realistic estimation of ecosystem service benefits associated with wetlands requires reasonable simulation of the hydrology of each site and realistic simulation of the upland and wetland plant growth cycles. Objectives of this study were to quantify leaf area index (LAI), light extinction coefficient (k), and plant nitrogen (N), phosphorus (P), and potassium (K) concentrations in natural stands of representative plant species for some major plant functional groups in the United States. Functional groups in this study were based on these parameters and plant growth types to enable process‐based modeling. We collected data at four locations representing some of the main wetland regions of the United States. At each site, we collected on‐the‐ground measurements of fraction of light intercepted, LAI, and dry matter within the 2013–2015 growing seasons. Maximum LAI and k variables showed noticeable variations among sites and years, while overall averages and functional group averages give useful estimates for multisite simulation modeling. Variation within each species gives an indication of what can be expected in such natural ecosystems. For P and K, the concentrations from highest to lowest were spikerush (Eleocharis macrostachya), reed canary grass (Phalaris arundinacea), smartweed (Polygonum spp.), cattail (Typha spp.), and hardstem bulrush (Schoenoplectus acutus). Spikerush had the highest N concentration, followed by smartweed, bulrush, reed canary grass, and then cattail. These parameters will be useful for the actual wetland species measured and for the wetland plant functional groups they represent. These parameters and the associated process‐based models offer promise as valuable tools for evaluating environmental benefits of wetlands and for evaluating impacts of various agronomic practices in adjacent areas as they affect wetlands.
Effects of grassland management on plant C:N:P stoichiometry: implications for soil element cycling and storage
Authors: Heyburn Jemma , McKenzie Paul , Crawley Michael J. , Fornara Dario A. 
Published: October 2017

AbstractThe functioning of human‐managed grassland ecosystems strongly depends on how common management practices (e.g., animal grazing and the chronic addition of fertilizing materials to soils) interact to influence plant and soil element stoichiometry. Here we use data from a 22‐yr‐long grassland experiment to address whether and how plant element stoichiometry (i.e., carbon [C], nitrogen [N], phosphorus [P] ratios) might respond to (1) animal grazing, (2) agricultural liming (i.e., CaCO3) applications, and (3) nutrient fertilization. We also ask whether plant C:N:P stoichiometry could predict changes in soil N and P availability and in soil C, N, and P stocks. We found that grassland management significantly affected plant C:N:P ratios as predicted by ecological stoichiometry theory. For example, plant aboveground and belowground C:N and C:P ratios decreased under chronic N and P fertilization, respectively. Plant C:N and C:P ratios were significantly greater in unfertilized (control) soils. Also plant C:N ratios were highest under P‐only additions, whereas plant C:P ratios were highest under N‐only additions. However, unpredictable changes in C:N:P ratios also occurred, suggesting that plant tissue chemistry may not be a simple reflection of soil nutrient availability. Changes in plant C:nutrient ratios well predicted variation in soil nutrient availability, but not in soil C, N, and P stocks. Contrary to expectations, soil C stocks significantly increased with decreasing plant C:N ratios in the nutrient‐fertilized grasslands and not with increasing plant C:N ratios in the unfertilized grasslands. We suggest that a better mechanistic understanding of the negative relationship between plant C:N stoichiometry and soil C accrual will greatly help in improving the sustainability of human‐managed grasslands.
Ly9 (SLAMF3) receptor differentially regulates iNKT cell development and activation in mice
Authors: Cuenca Marta , Puñet‐Ortiz Joan , Ruart Maria , Terhorst Cox , Engel Pablo 
Published: October 2017

AbstractInvariant natural killer T (iNKT) cells develop into three subsets (NKT1, NKT2, and NKT17) expressing a distinct transcription factor profile, which regulates cytokine secretion upon activation. iNKT cell development in the thymus is modulated by signaling lymphocytic activation molecule family (SLAMF) receptors. In contrast to other SLAMF members, Ly9 (SLAMF3) is a non‐redundant negative regulator of iNKT cell development. Here, we show that Ly9 influences iNKT cell lineage differentiation. Ly9‐deficient mice on a BALB/c background contained a significantly expanded population of thymic NKT2 cells, while NKT1 cells were nearly absent in BALB/c.Ly9−/− thymus. Conversely, the number of peripheral NKT1 cells in BALB/c.Ly9−/− mice was comparable to that in wild‐type mice, indicating that the homeostasis of the different iNKT cell subsets may have distinct requirements depending on their tissue localization. Importantly, Ly9 absence also promoted NKT2 cell differentiation in the NKT1‐skewed C57BL/6 background. Furthermore, treatment of wild‐type mice with an agonistic monoclonal antibody directed against Ly9 impaired IL‐4 and IFN‐γ production and reduced by half the number of spleen iNKT cells, with a significant decrease in the proportion of NKT2 cells. Thus, anti‐Ly9 targeting could represent a novel therapeutic approach to modulate iNKT cell numbers and activation.
Automation of the Storing‐In Part of a Hydrogen‐Storage System using Liquid Organic Hydrogen Carriers
Authors: Milella Vito‐Oronzo , Koelpin Alexander , Schluecker Eberhard 
Published: October 2017

AbstractAccumulating electrical energy in decentralized electrical grids is a demanding task. Preliminary work exists on the charging and discharging of liquid organic hydrogen carriers (LOHCs). These carriers allow the storage of hydrogen by reversible hydrogenation of an aromatic compound. A challenge is that the chemical process has to be conducted within the power‐generating infrastructure, and therefore, continuous and fully automated implementation is mandatory. In this work, the fundamentals of controlling and automating LOHC‐based energy‐storage systems are presented. For this purpose, the identification of the controlled variable is performed before its influence on the reaction dynamics is determined. This results in a fully automated hydrogenation process, whereby the conductibility of the reaction, the performance, and the necessity of applying pressure pulsations to get a stable operation mode are shown. Derived from these results, the investigations help to establish LOHCs as feasible hydrogen carriers, which will be a decisive step to mid‐ and long‐term energy‐storage systems suitable to a modern smart‐grid infrastructure.
Upgrading of a Norwegian pressurized sand trap combined with an open air surge tank
Authors: Richter Wolfgang , Vereide Kaspar , Zenz Gerald 
Published: October 2017

AbstractIn 1988 the Tonstad power plant (Norway) was upgraded from 640 to 960 MW. The headrace system to the reservoirs was not upgraded except for an additional pressure shaft, surge tank and an additional sand trap. Even with about 50 % higher discharge in the main tunnel, the sand traps worked adequately after the commissioning. However, in recent years, higher flexibility of demand is challenging the power plant and has resulted in events with flushing of sediments to the turbines. Higher flexibility demands also challenge the current surge tank design. During one event, free surface flow is believed to have occurred in the sand trap since severe damage to two of the turbines was observed. This contribution presents the background of the power system situation at the Tonstad power plant and the current flexibility demands of the power market and its challenges for the hydraulic system, as well as the proposals to solve the sand trap issues and the oscillation demands for the surge tank. The paper discusses the possibility of utilizing a model predictive controller with real‐time flow simulations to solve the challenges without structural reconstruction, and possible options should structural reconstruction be necessary. The contribution compares analysed options for improving the efficiency of sand traps. Finally, an outlook is offered to future demands for flexibility in hydropower plants with increasing supply of renewable power sources.
Challenges with regard to road tunnel structures – Assement management by Asfinag
Authors: Honeger Christian , Engelbogen Siegfried , Pucher Michael 
Published: October 2017

AbstractAsfinag (Autobahnen‐ und Schnellstraßen‐Finanzierungs AG) has the commission to oversee the entire Austrian high‐speed road network. Tunnel safety is an important focus. In the period between 2004, when the tunnel improvement programme started, and the first months of 2019, about EUR 5.7 billion will have been invested in the upgrading of tunnels as well as the optimisation of tunnel safety equipment. Along with these investments, there is also a focus on optimising the performance of lifecycles without risking non‐compliance with safety standards. Tunnel refurbishment measures are planned and carried out on the basis of regular checks and assessments, taking into consideration requirements with regard to both construction engineering and electrical equipment while at the same time pursuing the aim of optimising cost‐effectiveness. This paper also addresses the challenges resulting from the fact that the lifecycle of the tunnel structure differs from that of the tunnel equipment. Both the medium‐term and the long‐term planning of refurbishment measures should be prepared in detail to the greatest extent possible, so that the organisation can best guarantee both safety and cost‐effectiveness.