bluuebunny/crossref_metadata_2025_split huggingface dataset:
Homogeneous Gas‐Liquid Distribution for Monolithic Structures via a Needle Distributor
Authors: Meitzner Christine , Hilpmann Gerd , Schäfer Thomas , Haase Stefan , Lange Matthias , Hampel Uwe 
Published: July 2017

AbstractStructured catalysts are a widely discussed approach for process intensification of chemical multiphase reactors. But equal to common catalyst structures, homogeneous educt distribution along the catalytic surface is mandatory for high reactor performance. Especially monolithic structures require a homogeneous initial fluid distribution. A novel distribution concept for gas‐liquid flow through arbitrary channel matrices is presented. It is based on the injection principle where gas and liquid are inserted directly into the channels. A prototype for different cell densities was built and tested by various measurement techniques: gravimetry, X‐ray tomography, and an optical fiber sensor. Additionally, the flow regime per channel was detected as equal to single‐channel conditions.
An Eulerian‐Eulerian Computational Approach for Simulating Descending Gas‐Liquid Flows in Reactors with Solid Foam Internals
Authors: Subramanian Kumar , Zalucky Johannes , Schubert Markus , Lucas Dirk , Hampel Uwe 
Published: July 2017

AbstractChemical reactors with new types of packings, such as metallic and ceramic open‐pore foams, have become subjects of scientific and engineering interest in the past decades. For trickle bed reactors, the new packing types provide favorable conditions, such as high specific surface area and low pressure drop, which are believed to contribute to an intensification of mass and heat transfer. Here, an attempt was made to model and predict the flow pattern and liquid distribution in a trickle bed reactor with solid foams, using computational fluid dynamics. A three‐dimensional model based on the relative permeability approach was adopted, where gas and liquid phases flow co‐currently downwards through a reactor with SiSiC ceramic foams as internals. The influence of both mechanical and capillary dispersion was included and studied in detail for foams of two different pore densities and for different initial distribution patterns.
Urea Decomposition in Selective Catalytic Reduction on V2O5/WO3/TiO2 Catalyst in Diesel Exhaust
Authors: Goldbach Martin , Roppertz Andreas , Langenfeld Philipp , Wackerhagen Mandy , Füger Sven , Kureti Sven 
Published: July 2017

AbstractSelective catalytic reduction (SCR) of NOx by AdBlue and NH3 on monolithic V2O5/WO3/TiO2 catalyst was studied under flow conditions realistic for diesel exhaust. The tests provided same standard and fast SCR for AdBlue and NH3 from 150 to 350 °C. For standard urea‐SCR, axial concentration profiles were checked by monoliths with different lengths evidencing incomplete conversion of urea and isocyanic acid at low temperatures. But SCR was not clearly affected by under‐stoichiometric NH3 as substantiated by kinetic analysis. However, above 250 °C, SCR was limited by internal mass transport indicated by Weisz‐Prater criterion and lower activation barrier. Formation of deposits was investigated at 175 °C and below showing some urea around the nozzle, whereas cyanuric acid and biuret additionally formed around the catalyst.
Dioxygen Binding to Protonated Heme in the Gas Phase, an Intermediate Between Ferric and Ferrous Heme
Authors: Shafizadeh Niloufar , Soorkia Satchin , Grégoire Gilles , Broquier Michel , Crestoni Maria‐Elisa , Soep Benoît 
Published: July 2017

AbstractWith a view to characterizing the influence of the electronic structure of the Fe atom on the nature of its bond with dioxygen (O2) in heme compounds, a study of the UV/Vis action spectra and binding energies of heme‐O2 molecules has been undertaken in the gas phase. The binding reaction of protonated ferrous heme [FeII‐hemeH]+ with O2 has been studied in the gas phase by determining the equilibrium of complexed [FeII‐hemeH(O2)]+ with uncomplexed protonated heme in an ion trap at controlled temperatures. The binding energy of O2 to the Fe atom of protonated ferrous heme was obtained from a van't Hoff plot. Surprisingly, this energy (1540±170 cm−1, 18.4±2 kJ mol−1) is intermediate between those of ferric heme and ferrous heme. This result is interpreted in terms of a delocalization of the positive charge over the porphyrin cycle, such that the Fe atom bears a fractional positive charge. The resulting electron distribution on the Fe atom differs notably from that of a purely low‐spin ferrous heme [FeII‐heme(O2)] complex, as deduced from its absorption spectrum. It also differs from that of ferric heme [FeIII‐heme(O2)]+, as evidenced by the absorption spectra. Protonated heme creates a specific bond that cannot accommodate strong σ donation.
Synthesis‐oriented double‐loop feedback model
Authors: van Hartingsveldt Koen , Verhoeven Chris. J. M. , van Roermund Arthur H. M. 
Published: July 2017

SummaryThis paper presents a new feedback model that focuses on the synthesis rather than the analysis of feedback amplifiers. First, a single‐loop synthesis‐oriented feedback model is developed that enables the full synthesis of such amplifiers in a hierarchical and systematic way. This model is subsequently extended to a double‐loop synthesis model, so that also feedback amplifiers with a characteristic input or output impedance—employing two feedback loops—can be synthesized through the same systematic approach. That these new models are suitable for synthesis lies in the fact that they map directly to the circuit level, such that the intended, asymptotic behavior as well as the various individual contributors to the deviation from this intended behavior, like finite loop gain, non‐ideal input and output impedances of the forward gain block, direct feed‐through and attenuations outside the feedback loop(s), are clearly distinguished and can be assigned to the responsible sections of the network. For this purpose, the double‐loop synthesis model makes the transfers of the two feedback networks explicitly visible, so that it gives immediate insight in how to design these networks to get the required signal transfer and characteristic impedance. Copyright © 2017 John Wiley & Sons, Ltd.
A Three‐Year Longitudinal Study of Reading and Spelling Difficulty in Chinese Developmental Dyslexia: The Matter of Morphological Awareness
Authors: Tong Xiuhong , McBride Catherine , Lo Jason Chor Ming , Shu Hua 
Published: July 2017

In the present study, we used a three‐time point longitudinal design to investigate the associations of morphological awareness to word reading and spelling in a small group of those with and without dyslexia taken from a larger sample of 164 Hong Kong Chinese children who remained in a longitudinal study across ages 6, 7 and 8. Among those 164 children, 15 had been diagnosed as having dyslexia by professional psychologists, and 15 other children manifested average reading ability and had been randomly selected from the sample for comparison. All children were administered a battery of tasks including Chinese character recognition, word dictation, morphological awareness, phonological awareness and rapid automatized naming. Multivariate analysis of variance and predictive discriminate analysis were performed to examine whether the dyslexic children showed differences in the cognitive‐linguistic tasks in comparison with controls. Results suggested that the dyslexic groups had poorer performance in morphological awareness and RAN across all 3 years. However, phonological awareness was not stable in distinguishing the groups. Findings suggest that morphological awareness is a relatively strong correlate of spelling difficulties in Chinese, but phonological awareness is not. Copyright © 2017 John Wiley & Sons, Ltd.
Predicting life history parameters for all fishes worldwide
Authors: Thorson James T. , Munch Stephan B. , Cope Jason M. , Gao Jin 
Published: July 2017

AbstractScientists and resource managers need to know life history parameters (e.g., average mortality rate, individual growth rate, maximum length or mass, and timing of maturity) to understand and respond to risks to natural populations and ecosystems. For over 100 years, scientists have identified “life history invariants” (LHI) representing pairs of parameters whose ratio is theorized to be constant across species.LHIthen promise to allow prediction of many parameters from field measurements of a few important traits. UsingLHIin this way, however, neglects any residual patterns in parameters when making predictions. We therefore apply a multivariate model for eight variables (seven parameters and temperature) in over 32,000 fishes, and include taxonomic structure for residuals (with levels for class, order, family, genus, and species). We illustrate that this approach predicts variables probabilistically for taxa with many or few data. We then use this model to resolve three questions regarding life history parameters in fishes. Specifically we show that (1) on average there is a 1.24% decrease in the Brody growth coefficient for every 1% increase in maximum size; (2) the ratio of natural mortality rate and growth coefficient is not anLHIbut instead varies systematically based on the timing of maturation, where movement along this life history axis is predictably correlated with species taxonomy; and (3) three variables must be known per species to precisely predict remaining life history variables. We distribute our predictive model as an R package,FishLife, to allow future life history predictions for fishes to be conditioned on taxonomy and life history data for fishes worldwide. This package also contains predictions (and predictive intervals) for mortality, maturity, size, and growth parameters for all described fishes.
Division within the North American boreal forest: Ecological niche divergence between the Bicknell's Thrush (Catharus bicknelli) and Gray‐cheeked Thrush (C. minimus)
Authors: FitzGerald Alyssa M. 
Published: July 2017

AbstractSister species that diverged in allopatry in similar environments are expected to exhibit niche conservatism. Using ecological niche modeling and a multivariate analysis of climate and habitat data, I test the hypothesis that the Bicknell's Thrush (Catharus bicknelli) and Gray‐cheeked Thrush (C. mimimus), sister species that breed in the North American boreal forest, show niche conservatism. Three tree species that are important components of breeding territories of both thrush species were combined with climatic variables to create niche models consisting of abiotic and biotic components. Abiotic‐only, abiotic+biotic, and biotic‐only models were evaluated using the area under the curve (AUC) criterion. Abiotic+biotic models had higher AUC scores and did not over‐project thrush distributions compared to abiotic‐only or biotic‐only models. From the abiotic+biotic models, I tested for niche conservatism or divergence by accounting for the differences in the availability of niche components by calculating (1) niche overlap from ecological niche models and (2) mean niche differences of environmental values at occurrence points. Niche background similarity tests revealed significant niche divergence in 10 of 12 comparisons, and multivariate tests revealed niche divergence along 2 of 3 niche axes. The Bicknell's Thrush breeds in warmer and wetter regions with a high abundance of balsam fir (Abies balsamea), whereas Gray‐cheeked Thrush often co‐occurs with black spruce (Picea mariana). Niche divergence, rather than conservatism, was the predominant pattern for these species, suggesting that ecological divergence has played a role in the speciation of the Bicknell's Thrush and Gray‐cheeked Thrush. Furthermore, because niche models were improved by the incorporation of biotic variables, this study validates the inclusion of relevant biotic factors in ecological niche modeling to increase model accuracy.
Social dilemma in the external immune system of the red flour beetle? It is a matter of time
Authors: Gokhale Chaitanya S. , Traulsen Arne , Joop Gerrit 
Published: July 2017

AbstractSociobiology has revolutionized our understanding of interactions between organisms. Interactions may present a social dilemma where the interests of individual actors do not align with those of the group as a whole. Viewed through a sociobiological lens, nearly all interactions can be described regarding their costs and benefits, and a number of them then resemble a social dilemma. Numerous experimental systems, from bacteria to mammals, have been proposed as models for studying such dilemmas. Here, we make use of the external immune system of the red flour beetle, Tribolium castaneum, to investigate how the experimental duration can affect whether the external secretion comprises a social dilemma or not. Some beetles (secretors) produce a costly quinone‐rich external secretion that inhibits microbial growth in the surrounding environment, providing the secretors with direct personal benefits. However, as the antimicrobial secretion acts in the environment of the beetle, it is potentially also advantageous to other beetles (nonsecretors), who avoid the cost of producing the secretion. We test experimentally if the secretion qualifies as a public good. We find that in the short term, costly quinone secretion can be interpreted as a public good presenting a social dilemma where the presence of secretors increases the fitness of the group. In the long run, the benefit to the group of having more secretors vanishes and becomes detrimental to the group. Therefore, in such seminatural environmental conditions, it turns out that qualifying a trait as social can be a matter of timing.
Early‐life foraging: Behavioral responses of newly fledged albatrosses to environmental conditions
Authors: de Grissac Sophie , Bartumeus Frederic , Cox Sam L. , Weimerskirch Henri 
Published: July 2017

AbstractIn order to survive and later recruit into a population, juvenile animals need to acquire resources through the use of innate and/or learnt behaviors in an environment new to them. For far‐ranging marine species, such as the wandering albatross Diomedea exulans, this is particularly challenging as individuals need to be able to rapidly adapt and optimize their movement strategies in response to the highly dynamic and heterogeneous nature of their open‐ocean pelagic habitats. Critical to this is the development and flexibility of dispersal and exploratory behaviors. Here, we examine the movements of eight juvenile wandering albatrosses, tracked using GPS/Argos satellite transmitters for eight months following fledging, and compare these to the trajectories of 17 adults to assess differences and similarities in behavioral strategies through time. Behavioral clustering algorithms (Expectation Maximization binary Clustering) were combined with multinomial regression analyses to investigate changes in behavioral mode probabilities over time, and how these may be influenced by variations in day duration and in biophysical oceanographic conditions. We found that juveniles appeared to quickly acquire the same large‐scale behavioral strategies as those employed by adults, although generally more time was spent resting at night. Moreover, individuals were able to detect and exploit specific oceanographic features in a manner similar to that observed in adults. Together, the results of this study suggest that while shortly after fledging juvenile wandering albatrosses are able to employ similar foraging strategies to those observed in adults, additional skills need to be acquired during the immature period before the efficiency of these behaviors matches that of adults.
Maintaining genetic integrity of coexisting wild and domestic populations: Genetic differentiation between wild and domestic Rangifer with long traditions of intentional interbreeding
Authors: Anderson David G. , Kvie Kjersti S. , Davydov Vladimir N. , Røed Knut H. 
Published: July 2017

AbstractThis study investigates the genetic effect of an indigenous tradition of deliberate and controlled interbreeding between wild and domestic Rangifer. The results are interpreted in the context of conservation concerns and debates on the origin of domestic animals. The study is located in Northeastern Zabaĭkal'e, Russia at approximately 57 degrees North latitude. Blood and skin samples, collected from wild and domestic Rangifer, are analyzed for their mtDNA and microsatellite signatures. Local husbandry traditions are documented ethnographically. The genetic data are analyzed with special reference to indigenous understandings of the distinctions between local domestic types and wild Rangifer. The genetic results demonstrate a strong differentiation between wild and domestic populations. Notably low levels of mtDNA haplotype sharing between wild and domestic reindeer, suggest mainly male‐mediated gene flow between the two gene pools. The nuclear microsatellite results also point to distinct differences between regional domestic clusters. Our results indicate that the Evenki herders have an effective breeding technique which, while mixing pedigrees in the short term, guards against wholesale introgression between wild and domestic populations over the long term. They support a model of domestication where wild males and domestic females are selectively interbred, without hybridizing the two populations. Our conclusions inform a debate on the origins of domestication by documenting a situation where both wild and domestic types are in constant interaction. The study further informs a debate in conservation biology by demonstrating that certain types of controlled introgression between wild and domestic types need not reduce genetic diversity.
Too hot to die? The effects of vegetation shading on past, present, and future activity budgets of two diurnal skinks from arid Australia
Authors: Grimm‐Seyfarth Annegret , Mihoub Jean‐Baptiste , Henle Klaus 
Published: July 2017

AbstractBehavioral thermoregulation is an important mechanism allowing ectotherms to respond to thermal variations. Its efficiency might become imperative for securing activity budgets under future climate change. For diurnal lizards, thermal microhabitat variability appears to be of high importance, especially in hot deserts where vegetation is highly scattered and sensitive to climatic fluctuations. We investigated the effects of a shading gradient from vegetation on body temperatures and activity timing for two diurnal, terrestrial desert lizards, Ctenotus regius, and Morethia boulengeri, and analyzed their changes under past, present, and future climatic conditions. Both species’ body temperatures and activity timing strongly depended on the shading gradient provided by vegetation heterogeneity. At high temperatures, shaded locations provided cooling temperatures and increased diurnal activity. Conversely, bushes also buffered cold temperature by saving heat. According to future climate change scenarios, cooler microhabitats might become beneficial to warm‐adapted species, such as C. regius, by increasing the duration of daily activity. Contrarily, warmer microhabitats might become unsuitable for less warm‐adapted species such as M. boulengeri for which midsummers might result in a complete restriction of activity irrespective of vegetation. However, total annual activity would still increase provided that individuals would be able to shift their seasonal timing towards spring and autumn. Overall, we highlight the critical importance of thermoregulatory behavior to buffer temperatures and its dependence on vegetation heterogeneity. Whereas studies often neglect ecological processes when anticipating species’ responses to future climate change the strongest impact of a changing climate on terrestrial ectotherms in hot deserts is likely to be the loss of shaded microhabitats rather than the rise in temperature itself. We argue that conservation strategies aiming at addressing future climate changes should focus more on the cascading effects of vegetation rather than on shifts of species distributions predicted solely by climatic envelopes.
Influences of thermal environment on fish growth
Authors: Boltaña Sebastián , Sanhueza Nataly , Aguilar Andrea , Gallardo‐Escarate Cristian , Arriagada Gabriel , Valdes Juan Antonio , Soto Doris , Quiñones Renato A. 
Published: July 2017

AbstractThermoregulation in ectothermic animals is influenced by the ability to effectively respond to thermal variations. While it is known that ectotherms are affected by thermal changes, it remains unknown whether physiological and/or metabolic traits are impacted by modifications to the thermal environment. Our research provides key evidence that fish ectotherms are highly influenced by thermal variability during development, which leads to important modifications at several metabolic levels (e.g., growth trajectories, microstructural alterations, muscle injuries, and molecular mechanisms). In Atlantic salmon (Salmo salar), a wide thermal range (ΔT 6.4°C) during development (posthatch larvae to juveniles) was associated with increases in key thermal performance measures for survival and growth trajectory. Other metabolic traits were also significantly influenced, such as size, muscle cellularity, and molecular growth regulators possibly affected by adaptive processes. In contrast, a restricted thermal range (ΔT 1.4°C) was detrimental to growth, survival, and cellular microstructure as muscle growth could not keep pace with increased metabolic demands. These findings provide a possible basic explanation for the effects of thermal environment during growth. In conclusion, our results highlight the key role of thermal range amplitude on survival and on interactions with major metabolism‐regulating processes that have positive adaptive effects for organisms.