bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hollow Porous Carbon with in situ Generated Monodisperse Gold Nanoclusters for Efficient CO Oxidation
Authors: Qu Jiafu , Zhu Haiguang , Chen Dongyun , Li Najun , Xu Qingfeng , Xie Jianping , Li Hua , He Jinghui , Lu Jianmei 
Published: October 2017

AbstractPrecious metals (Au and Pt) loaded in a mesoporous substrate (carbon and silicon) are popular materials for catalytic CO oxidation. However, the preparation of noble metals and the metal particle size after deposition in the pore channels of the mesoporous materials are serious issues for environmentally friendly applications. Herein, a gold‐decorated hollow porous carbon nanospheres (Au/HPCN) catalyst, which is both durable and uniform, is synthesized by a facile in situ reduction route for continuous CO oxidation. In our approach, HPCNs were selected as the substrate because of their thermal stability, well‐defined nanostructure, and large surface area. Au nanoclusters were loaded in the pore channels of HPCN because of their stability and catalytic performance. The as‐synthesized nanocomposite possesses a uniform size and highly porous structure. Moreover, CO oxidation occurred both during the reduction of Au3+ ions and after the preparation of Au/HPCN.
A Quantification of the Soai Reaction
Authors: Noble‐Terán María E. , Cruz José‐Manuel , Micheau Jean‐Claude , Buhse Thomas 
Published: October 2017

AbstractA kinetic and thermodynamic model of the Soai reaction is presented. This allows the quantitative determination of five rates constants and one equilibrium constant. The model is realistic as it integrates the results of the most recently published XRD structural data and DFT calculations and selected experimental kinetic data. Equipped with the extracted parameters from the numerical fitting of the time evolution of both the substrate concentration and the enantiomeric excess, the model was able to mimic strong asymmetric amplification from extremely low initial enantiomeric excess and spontaneous mirror‐image symmetry breaking under “zero‐catalyst” conditions. It also reproduces the crystallization conditions by exhibiting the preferential accumulation of the corresponding oligomeric species in solution. An important point is also illustrated: the autocatalytic asymmetric amplification is not located on the expected easily detectable dimers but on the less concentrated tetrameric species.
The Applications of Metal−Organic Frameworks in Electrochemical Sensors
Authors: Liu Lantao , Zhou Yanli , Liu Shuang , Xu Maotian 
Published: October 2017

AbstractMetal−organic frameworks (MOFs), synthesized by assembling metal nods with organic linkers, are highly ordered crystalline materials. MOFs have attracted much attention for applications in electrochemical sensors, because of their unique chemical and physical properties including ultrahigh porosity, large surface area, tunable structure, and high thermal and chemical stability. In particular, redox and catalytic active sites introduced by use of active metal ions and/or ligands endow MOFs with the functions required in electrochemical sensing. Moreover, precise chemical modification of functional molecules and immobilization with metal nanoparticles, carbon nanostructures, and biomolecules could promote their electrochemical performances. In this Review, we focus on recent progress achieved in MOF research with respect to general sensing principles and analytical performances of electrochemical sensors. The evaluation and challenges governing the detection of the assays are also discussed.
Electrochemical and Reactivity Studies of N→Sn Coordinated Distannynes
Authors: Novák Miroslav , Mikysek Tomáš , Růžička Aleš , Dostál Libor , Jambor Roman 
Published: October 2017

AbstractStudies are focused on the redox potentials of N→Sn coordinated distannnynes {L1–3Sn}2 (L1=1, L2=2 and L3=3, in which L1 is [C6H3‐2,6‐(Me2NCH2)2]−, L2 is [C6H2‐2,4‐tBu2‐6‐(Et2NCH2)]− and L3 is [C6H2‐2,4‐tBu2‐6‐(DippN=CH)]−; Dipp=2,6‐diisopropylphenyl), containing the tin atom in oxidation state +I. Distannynes 1–3 were used as ligands for transition metals, and complexes [{L1Sn}2⋅Fe(CO)4] (4) and [{L2Sn}2⋅Fe(CO)4] (5) were prepared. The set of N→Sn coordinated distannynes 1–5 was studied by cyclic voltammetry measurements and the oxidation potentials of tin atoms in 1–5 were determined. The redox potentials are influenced by either ligands L1–3 or SnI→Fe coordination. Oxidation reactions of 1–3 were also studied. The reaction of 2 with (2,2,6,6‐tetramethylpiperidin‐1‐yl)oxyl (TEMPO) provided mixed organotin oxide {(L2SnO)(L2)Sn(μ‐O)}2 (6) as a consequence of the instability of the expected {L2Sn⋅TEMPO} complex. To support this proposed mechanism, the N→Ge coordinated digermyne {L2Ge}2 (7) was prepared. The reaction of 7 with TEMPO provided the expected complex {L2Ge⋅TEMPO} (8).
Phase Equilibrium of TiO2 Nanocrystals in Flame‐Assisted Chemical Vapor Deposition
Authors: Liu Changran , Camacho Joaquin , Wang Hai 
Published: October 2017

AbstractNano‐scale titanium oxide (TiO2) is a material useful for a wide range of applications. In a previous study, we showed that TiO2 nanoparticles of both rutile and anatase crystal phases could be synthesized over the size range of 5 to 20 nm in flame‐assisted chemical vapor deposition. Rutile was unexpectedly dominant in oxygen‐lean synthesis conditions, whereas anatase is the preferred phase in oxygen‐rich gases. The observation is in contrast to the 14 nm rutile–anatase crossover size derived from the existing crystal‐phase equilibrium model. In the present work, we made additional measurements over a wider range of synthesis conditions; the results confirm the earlier observations. We propose an improved model for the surface energy that considers the role of oxygen desorption at high temperatures. The model successfully explains the observations made in the current and previous work. The current results provide a useful path to designing flame‐assisted chemical vapor deposition of TiO2 nanocrystals with controllable crystal phases.
2D Spherulites of a Semi‐Fluorinated Alkane: Controlled Access to Either Radial Or Ring‐Banded Morphologies
Authors: Liu Xianhe , Mielke Salomé , Contal Christophe , Favier Damien , Yamamoto Akihisa , Tanaka Motomu , Krafft Marie Pierre 
Published: October 2017

AbstractThin films of a semi‐fluorinated alkane cast onto solid substrates consist of well‐formed two‐dimensional non‐birefringent ring‐banded and/or radial spherulites. Controlling the experimental conditions allows orientation of the crystallization toward either radial‐only or ring‐banded‐only morphologies. Intermediate states were also captured in which both radial and ring‐banded spherulites coexist. Monitoring of the formation of these intermediate states brought evidence for a first crystallization mode that sweeps radially outwards from a central nucleus until the propagating front edge experiences a second crystallization mode that proceeds through a diffusion‐controlled rhythmic crystallization mechanism that leads to high (≈2 μm) concentric ridges. These 2D spherulites were investigated by optical and atomic force microscopies, interferometric profilometry, and off‐specular neutron scattering.
Controlled Cortical Impact in the Rat
Authors: Dean Dana D. , Frank Joseph A. , Turtzo L. Christine 
Published: October 2017

AbstractTraumatic brain injury (TBI) is a major cause of death and disability world‐wide. Following initial injury, TBI patients can face long‐term disability in the form of cognitive, physical, and psychological deficits, depending on the severity and location of injury. This results in an economic burden in the United States estimated to be $60 billion due to health‐care costs and loss of productivity. TBI is a significant area of active research interest for both military and civilian medicine. Numerous pre‐clinical animal models of TBI are used to characterize the anatomical and physiological pathways involved and to evaluate therapeutic interventions. Due to its flexibility and scalability, controlled cortical impact (CCI) is one of the most commonly used preclinical TBI models. This unit provides a basic CCI protocol performed in the rat. © 2017 by John Wiley & Sons, Inc.
Formal verification of a radio network random access protocol
Authors: Roumane Ahmed , Kechar Bouabdellah , Kouninef Belkacem 
Published: October 2017

SummaryIn this paper, the random access procedure of Universal Mobile Telecommunications System network is investigated. We have proposed a model based on communicating timed automata that represents the main functions related to the random access procedure including the user equipment, the base station (node B or BTS), and the channel. Then, we have used computational tree logic formula to specify the proprieties to be verified. The model and the formulas serve as inputs to the model checker, which is used as a verification engine, ie, UPPAAL and SPIN. The formal verification approach shows that the protocol has several drawbacks that may not be detected by simulation.
Cumulative effects of wildfires on forest dynamics in the eastern Cascade Mountains, USA
Authors: Reilly Matthew J. , Elia Mario , Spies Thomas A. , Gregory Matthew J. , Sanesi Giovanni , Lafortezza Raffaele 
Published: October 2017

AbstractWildfires pose a unique challenge to conservation in fire‐prone regions, yet few studies quantify the cumulative effects of wildfires on forest dynamics (i.e., changes in structural conditions) across landscape and regional scales. We assessed the contribution of wildfire to forest dynamics in the eastern Cascade Mountains, USA from 1985 to 2010 using imputed maps of forest structure (i.e., tree size and canopy cover) and remotely sensed burn severity maps. We addressed three questions: (1) How do dynamics differ between the region as a whole and the unburned portion of the region? (2) How do dynamics vary among vegetation zones differing in biophysical setting and historical fire frequency? (3) How have forest structural conditions changed in a network of late successional reserves (LSRs)? Wildfires affected 10% of forests in the region, but the cumulative effects at this scale were primarily slight losses of closed‐canopy conditions and slight gains in open‐canopy conditions. In the unburned portion of the region (the remaining 90%), closed‐canopy conditions primarily increased despite other concurrent disturbances (e.g., harvest, insects). Although the effects of fire were largely dampened at the regional scale, landscape scale dynamics were far more variable. The warm ponderosa pine and cool mixed conifer zones experienced less fire than the region as a whole despite experiencing the most frequent fire historically. Open‐canopy conditions increased slightly in the mixed conifer zone, but declined across the ponderosa pine zone even with wildfires. Wildfires burned 30% of the cold subalpine zone, which experienced the greatest increase in open‐canopy conditions and losses of closed‐canopy conditions. LSRs were more prone to wildfire than the region as a whole, and experienced slight declines in late seral conditions. Despite losses of late seral conditions, wildfires contributed to some conservation objectives by creating open habitats (e.g., sparse early seral and woodland conditions) that otherwise generally decreased in unburned landscapes despite management efforts to increase landscape diversity. This study demonstrates the potential for wildfires to contribute to regional scale conservation objectives, but implications for management and biodiversity at landscape scales vary geographically among biophysical settings, and are contingent upon historical dynamics and individual species habitat preferences.
Body size variation in aquatic consumers causes pervasive community effects, independent of mean body size
Authors: Carlson Bradley E. , Langkilde Tracy 
Published: October 2017

AbstractIntraspecific phenotypic variation is a significant component of biodiversity. Body size, for example, is variable and critical for structuring communities. We need to understand how homogenous and variably sized populations differ in their ecological responses or effects if we are to have a robust understanding of communities. We manipulated body size variation in consumer (tadpole) populations in mesocosms (both with and without predators), keeping mean size and density of these consumers constant. Size‐variable consumer populations exhibited stronger antipredator responses (reduced activity), which had a cascading effect of increasing the biomass of the consumer's resources. Predators foraged less when consumers were variable in size, and this may have mediated the differential effects of predators on the community composition of alternative prey (zooplankton). All trophic levels responded to differences in consumer size variation, demonstrating that intrapopulation phenotypic variability can significantly alter interspecific ecological interactions. Furthermore, we identify a key mechanism (size thresholds for predation risk) that may mediate impacts of size variation in natural communities. Together, our results suggest that phenotypic variability plays a significant role in structuring ecological communities.
Strong positive effects of termites on savanna bird abundance and diversity are amplified by large herbivore exclusion
Authors: Moe Stein R. , Eldegard Katrine , Rannestad Ole Tobias , Okullo Paul , Lindtjørn Ommund , Støen Ole Gunnar , Dale Svein 
Published: October 2017

AbstractVast areas of the African savanna landscapes are characterized by tree‐covered Macrotermes termite mounds embedded within a relatively open savanna matrix. In concert with termites, large herbivores are important determinants of savanna woody vegetation cover. The relative cover of woody species has considerable effects on savanna function. Despite the potentially important ecological relationships between termite mounds, woody plants, large herbivores, and birds, these associations have previously received surprisingly little attention. We experimentally studied the effects of termites and large herbivores on the avian community in Lake Mburo National Park, Uganda, where woody vegetation is essentially limited to termite mounds. Our experiment comprised of four treatments in nine replicates; unfenced termite mounds, fenced mounds (excluding large mammals), unfenced adjacent savanna, and fenced savanna. We recorded species identity, abundance, and behavior of all birds observed on these plots over a two‐month period, from late dry until wet season. Birds used termite mounds almost exclusively, with only 3.5% of observations occurring in the treeless intermound savanna matrix. Mean abundance and species richness of birds doubled on fenced (large herbivores excluded) compared to unfenced mounds. Feeding behavior increased when large mammals were excluded from mounds, both in absolute number of observed individuals, and relative to other behaviors. This study documents the fundamental positive impact of Macrotermes termites on bird abundance and diversity in an African savanna. Birds play crucial functional roles in savanna ecosystems, for example, by dispersing fruits or regulating herbivorous insect populations. Thus, the role of birds in savanna dynamics depends on the distribution and abundance of termite mounds.
Seasonal genetic variation associated with population dynamics of a poecilogonous polychaete worm
Authors: Thonig Anne , Banta Gary Thomas , Hansen Benni Winding , Knott K. Emily 
Published: October 2017

AbstractPoecilogonous species show variation in developmental mode, with larvae that differ both morphologically and ecologically. The spionid polychaete Pygospio elegans shows variation in developmental mode not only between populations, but also seasonally within populations. We investigated the consequences of this developmental polymorphism on the spatial and seasonal genetic structure of P. elegans at four sites in the Danish Isefjord‐Roskilde‐Fjord estuary at six time points, from March 2014 until February 2015. We found genetic differentiation between our sampling sites as well as seasonal differentiation at two of the sites. The seasonal genetic shift correlated with the appearance of new size cohorts in the populations. Additionally, we found that the genetic composition of reproductive individuals did not always reflect the genetic composition of the entire sample, indicating that variance in reproductive success among individuals is a likely explanation for the patterns of chaotic genetic patchiness observed during this and previous studies. The heterogeneous, unpredictable character of the estuary might maintain poecilogony in P. elegans as a bet‐hedging strategy in the Isefjord‐Roskilde‐Fjord complex in comparison with other sites where P. elegans are expected to be fixed to a certain mode of development.
Conservation of social effects (Ψ) between two species of Drosophila despite reversal of sexual dimorphism
Authors: Signor Sarah A. , Abbasi Mohammad , Marjoram Paul , Nuzhdin Sergey V. 
Published: October 2017

AbstractIndirect genetic effects (IGEs) describe the effect of the genes of social partners on the phenotype of a focal individual. Here, we measure indirect genetic effects using the “coefficient of interaction” (Ψ) to test whether Ψ evolved between Drosophila melanogaster and D. simulans. We compare Ψ for locomotion between ethanol and nonethanol environments in both species, but only D. melanogaster utilizes ethanol ecologically. We find that while sexual dimorphism for locomotion has been reversed in D. simulans, there has been no evolution of social effects between these two species. What did evolve was the interaction between genotype‐specific Ψ and the environment, as D. melanogaster varies unpredictably between environments and D. simulans does not. In this system, this suggests evolutionary lability of sexual dimorphism but a conservation of social effects, which brings forth interesting questions about the role of the social environment in sexual selection.
A workflow of massive identification and application of intron markers using snakes as a model
Authors: Li Jiang‐Ni , He Chong , Guo Peng , Zhang Peng , Liang Dan 
Published: October 2017

AbstractRelative to the commonly used mitochondrial and nuclear protein‐coding genes, the noncoding intron sequences are a promising source of informative markers that have the potential to resolve difficult phylogenetic nodes such as rapid radiations and recent divergences. Yet many issues exist in the use of intron markers, which prevent their extensive application as conventional markers. We used the diverse group of snakes as an example to try paving the way for massive identification and application of intron markers. We performed a series of bioinformatics screenings which identified appropriate introns between single‐copy and conserved exons from two snake genomes, adding particular constraints on sequence length variability and sequence variability. A total of 1,273 candidate intron loci were retrieved. Primers for nested polymerase chain reaction (PCR) were designed for over a hundred candidates and tested in 16 snake representatives. 96 intron markers were developed that could be amplified across a broad range of snake taxa with high PCR successful rates. The markers were then applied to 49 snake samples. The large number of amplicons was subjected to next‐generation sequencing (NGS). An analytic strategy was developed to accurately recover the amplicon sequences, and approximately, 76% of the marker sequences were recovered. The average p‐distances of the intron markers at interfamily, intergenus, interspecies, and intraspecies levels were .168, .052, .015, and .004, respectively, suggesting that they were useful to study snake relationships of different evolutionary depths. A snake phylogeny was constructed with the intron markers, which produced concordant results with robust support at both interfamily and intragenus levels. The intron markers provide a convenient way to explore the signals in the noncoding regions to address the controversies on the snake tree. Our improved strategy of genome screening is effective and can be applied to other animal groups. NGS coupled with appropriate sequence processing can greatly facilitate the extensive application of molecular markers.
Body macronutrient composition is predicted by lipid and not protein content of the diet
Authors: Moatt Joshua P. , Hambly Catherine , Heap Elizabeth , Kramer Anna , Moon Fiona , Speakman John R. , Walling Craig A. 
Published: October 2017

AbstractDiet is an important determinant of fitness‐related traits including growth, reproduction, and survival. Recent work has suggested that variation in protein:lipid ratio and particularly the amount of protein in the diet is a key nutritional parameter. However, the traits that mediate the link between dietary macronutrient ratio and fitness‐related traits are less well understood. An obvious candidate is body composition, given its well‐known link to health. Here, we investigate the relationship between dietary and body macronutrient composition using a first‐generation laboratory population of a freshwater fish, the three‐spine stickleback (Gasterosteus aculeatus). Carbohydrate is relatively unimportant in the diet of predatory fish, facilitating the exploration of how dietary protein‐to‐lipid ratio affects their relative deposition in the body. We find a significant effect of lipid intake, rather than protein, on body protein:lipid ratio. Importantly, this was not a result of absorbing macronutrients in relation to their relative abundance in the diet, as the carcass protein:lipid ratios differed from those of the diets, with ratios usually lower in the body than in the diet. This indicates that individuals can moderate their utilization, or uptake, of ingested macronutrients to reach a target balance within the body. We found no effect of diet on swimming endurance, activity, or testes size. However, there was an effect of weight on testes size, with larger males having larger testes. Our results provide evidence for the adjustment of body protein:lipid ratio away from that of the diet. As dietary lipid intake was the key determinant of body composition, we suggest this occurs via metabolism of excess protein, which conflicts with the predictions of the protein leverage hypothesis. These results could imply that the conversion and excretion of protein is one of the causes of the survival costs associated with high‐protein diets.
A Novel Eutectic Mixture of Biphenyl and Diphenylmethane as a Potential Liquid Organic Hydrogen Carrier: Catalytic Hydrogenation
Authors: Han Da Jung , Jo Young Suk , Shin Byeong Soo , Jang Munjeong , Kang Jeong Won , Han Jong Hee , Nam Suk Woo , Yoon Chang Won 
Published: October 2017

AbstractA novel, liquid‐phase hydrogen storage material was produced by mixing biphenyl (C12H10, solid) and diphenylmethane (C13H12, liquid) with a mass ratio (wt %) of 35:65. The eutectic mixture was proved to be liquid at ambient temperature with a viscosity of 3.0 cP at 25 °C and a vapor pressure of 1.4 Pa at 25 °C, which potentially meets the requirements for an efficient hydrogen storage system. A theoretical study using COSMO‐RS method further confirms that an optimum composition of biphenyl and diphenylmethane for the formation of eutectic mixture is 37:63 by mass, which is very close to the composition found experimentally. The eutectic mixture exhibited a superior activity for hydrogenation reactions conducted at 120 °C under 50 bar of H2 pressure in the presence of a Ru (5 wt %)/Al2O3 catalyst. Hydrogen uptake of the eutectic mixture tested was close to full conversion, which corresponds to 6.9 wt % and 60.1 g L−1 of gravimetric and volumetric hydrogen storage capacities, respectively.