bluuebunny/crossref_metadata_2025_split huggingface dataset:
Oxygen Exchange Kinetics of SrTiO3 Single Crystals: A Non‐Destructive, Quantitative Method
Authors: Stöber Max , Cherkouk Charaf , Leisegang Tilmann , Schelter Matthias , Zosel Jens , Walter Juliane , Hanzig Juliane , Zschornak Matthias , Prucnal Slawomir , Böttger Roman , Meyer Dirk C. 
Published: March 2018

AbstractThe time‐resolved oxygen exchange rate of strontium titanate (SrTiO3) single crystals is studied by means of oxygen solid electrolyte coulometry (OSEC) and compared to model calculations. Experiments are performed on pure, ion implanted (Ni, Ag, O and N ions) and partially covered crystals with silver layer. In this work, a theoretical model is used, which is based on defect chemistry under equilibrium conditions. It is applied as a fit in order to determine the effective rate constants and activation energy of the oxygen exchange reaction on the crystal surface. OSEC is used for the first time to characterize kinetic parameters of oxygen exchange on single crystalline surfaces. Transmission electron microscopy and sputter X‐ray photoelectron spectroscopy are performed to determine structural and chemical changes after ion implantation.
Catching TFSI: A Computational–Experimental Approach to β‐Cyclodextrin‐Based Host–Guest Systems as electrolytes for Li‐Ion Batteries
Authors: Jeschke Steffen , Jankowski Piotr , Best Adam S. , Johansson Patrik 
Published: March 2018

AbstractCyclodextrins (CDs) are pyranoside‐based macromolecules with a hydrophobic cavity to encapsulate small molecules. They are used as molecular vehicles, for instance in pharmaceutical drug delivery or as solubility enhancer of monomers for their polymerization in aqueous solution. In this context, it was discovered about 10 years ago that the bis(trifluoromethylsulonyl)imide (TFSI) anion forms host–guest complexes with βCD in aqueous media. This sparked interest in using the TFSI anion in lithium‐based battery electrolytes open for its encapsulation by βCD as an attractive approach to increase the contribution of the cation to the total ion conductivity. By using semi‐empirical quantum mechanical (SQM) methods and the conductor‐like screening model for a real solvent (COSMO‐RS), a randomly methylated βCD (RMβCD) is here identified as a suitable host for TFSI when using organic solvents often used in battery technology. By combining molecular dynamics (MD) simulations with different NMR and FTIR experiments, the formation of the corresponding RMβCD–TFSI complex was investigated. Finally, the effects of the addition RMβCD to a set of electrolytes on the ion conductivity are measured and explained using three distinct scenarios.
Host species, and not environment, predicts variation in blood parasite prevalence, distribution, and diversity along a humidity gradient in northern South America
Authors: Pulgarín‐R Paulo C. , Gómez Juan P. , Robinson Scott , Ricklefs Robert E. , Cadena Carlos Daniel 
Published: March 2018

AbstractEnvironmental factors strongly influence the ecology and evolution of vector‐borne infectious diseases. However, our understanding of the influence of climatic variation on host–parasite interactions in tropical systems is rudimentary. We studied five species of birds and their haemosporidian parasites (Plasmodium and Haemoproteus) at 16 sampling sites to understand how environmental heterogeneity influences patterns of parasite prevalence, distribution, and diversity across a marked gradient in water availability in northern South America. We used molecular methods to screen for parasite infections and to identify parasite lineages. To characterize spatial heterogeneity in water availability, we used weather‐station and remotely sensed climate data. We estimated parasite prevalence while accounting for spatial autocorrelation, and used a model selection approach to determine the effect of variables related to water availability and host species on prevalence. The prevalence, distribution, and lineage diversity of haemosporidian parasites varied among localities and host species, but we found no support for the hypothesis that the prevalence and diversity of parasites increase with increasing water availability. Host species and host × climate interactions had stronger effects on infection prevalence, and parasite lineages were strongly associated with particular host species. Because climatic variables had little effect on the overall prevalence and lineage diversity of haemosporidian parasites across study sites, our results suggest that independent host–parasite dynamics may influence patterns in parasitism in environmentally heterogeneous landscapes.
Comparing the consequences of natural selection, adaptive phenotypic plasticity, and matching habitat choice for phenotype–environment matching, population genetic structure, and reproductive isolation in meta‐populations
Authors: Nicolaus Marion , Edelaar Pim 
Published: March 2018

AbstractOrganisms commonly experience significant spatiotemporal variation in their environments. In response to such heterogeneity, different mechanisms may act that enhance ecological performance locally. However, depending on the nature of the mechanism involved, the consequences for populations may differ greatly. Building on a previous model that investigated the conditions under which different adaptive mechanisms (co)evolve, this study compares the ecological and evolutionary population consequences of three very different responses to environmental heterogeneity: matching habitat choice (directed gene flow), adaptive plasticity (associated with random gene flow), and divergent natural selection. Using individual‐based simulations, we show that matching habitat choice can have a greater adaptive potential than plasticity or natural selection: it allows for local adaptation while protecting genetic polymorphism despite global mating or strong environmental changes. Our simulations further reveal that increasing environmental fluctuations and unpredictability generally favor the emergence of specialist genotypes but that matching habitat choice is better at preventing local maladaptation by individuals. This confirms that matching habitat choice can speed up the genetic divergence among populations, cause indirect assortative mating via spatial clustering, and hence even facilitate sympatric speciation. This study highlights the potential importance of directed dispersal in local adaptation and speciation, stresses the difficulty of deriving its operation from nonexperimental observational data alone, and helps define a set of ecological conditions which should favor its emergence and subsequent detection in nature.
The temperature‐size rule in Daphnia magna across different genetic lines and ontogenetic stages: Multiple patterns and mechanisms
Authors: Hoefnagel K. Natan , de Vries E. H. J. (Lisenka) , Jongejans Eelke , Verberk Wilco C. E. P. 
Published: March 2018

AbstractEctotherms tend to grow faster, but reach a smaller size when reared under warmer conditions. This temperature‐size rule (TSR) is a widespread phenomenon. Despite the generality of this pattern, no general explanation has been found. We therefore tested the relative importance of two proposed mechanisms for the TSR: (1) a stronger increase in development rate relative to growth rate at higher temperatures, which would cause a smaller size at maturity, and (2) resource limitation placing stronger constraints on growth in large individuals at higher temperatures, which would cause problems with attaining a large size in warm conditions. We raised Daphnia magna at eight temperatures to assess their size at maturity, asymptotic size, and size of their offspring. We used three clonal lines that differed in asymptotic size and growth rate. A resource allocation model was developed and fitted to our empirical data to explore the effect of both mechanisms for the TSR. The genetic lines of D. magna showed different temperature dependence of growth and development rates resulting in different responses for size at maturity. Also, at warm temperatures, growth was constrained in large, but not in small individuals. The resource allocation model could fit these empirical data well. Based on our empirical results and model explorations, the TSR of D. magna at maturity is best explained by a stronger increase in development rate relative to growth rate at high temperature, and the TSR at asymptotic size is best explained by a size‐dependent and temperature‐dependent constraint on growth, although resource limitation could also affect size at maturity. In conclusion, the TSR can take different forms for offspring size, size at maturity, and asymptotic size and each form can arise from its own mechanism, which could be an essential step toward finding a solution to this century‐old puzzle.
Distinct responses of soil respiration to experimental litter manipulation in temperate woodland and tropical forest
Authors: Bréchet Laëtitia M. , Lopez‐Sangil Luis , George Charles , Birkett Ali J. , Baxendale Catherine , Castro Trujillo Biancolini , Sayer Emma J. 
Published: March 2018

AbstractGlobal change is affecting primary productivity in forests worldwide, and this, in turn, will alter long‐term carbon (C) sequestration in wooded ecosystems. On one hand, increased primary productivity, for example, in response to elevated atmospheric carbon dioxide (CO2), can result in greater inputs of organic matter to the soil, which could increase C sequestration belowground. On other hand, many of the interactions between plants and microorganisms that determine soil C dynamics are poorly characterized, and additional inputs of plant material, such as leaf litter, can result in the mineralization of soil organic matter, and the release of soil C as CO2 during so‐called “priming effects”. Until now, very few studies made direct comparison of changes in soil C dynamics in response to altered plant inputs in different wooded ecosystems. We addressed this with a cross‐continental study with litter removal and addition treatments in a temperate woodland (Wytham Woods) and lowland tropical forest (Gigante forest) to compare the consequences of increased litterfall on soil respiration in two distinct wooded ecosystems. Mean soil respiration was almost twice as high at Gigante (5.0 μmol CO2 m−2 s−1) than at Wytham (2.7 μmol CO2 m−2 s−1) but surprisingly, litter manipulation treatments had a greater and more immediate effect on soil respiration at Wytham. We measured a 30% increase in soil respiration in response to litter addition treatments at Wytham, compared to a 10% increase at Gigante. Importantly, despite higher soil respiration rates at Gigante, priming effects were stronger and more consistent at Wytham. Our results suggest that in situ priming effects in wooded ecosystems track seasonality in litterfall and soil respiration but the amount of soil C released by priming is not proportional to rates of soil respiration. Instead, priming effects may be promoted by larger inputs of organic matter combined with slower turnover rates.
Coexistence of DC and CSMA in SRD channel access and resilience to LTE interference: A simulator‐based analysis
Authors: Bandeira Rita , Sousa Ivo , Queluz Maria Paula , Rodrigues António 
Published: March 2018

AbstractThe foreseen increased use of short‐range devices (SRDs) will boost the competition for radio channel access in license‐exempt frequency bands. Therefore, it is important to find out the most efficient SRD configurations in terms of their performance in high‐contention scenarios; moreover, it is crucial to ensure that SRD networks do not impair the radio systems that operate in neighboring licensed spectrum, and vice versa. This paper addresses the previous issues by simulating a building automation application scenario, where 2 channel access mechanisms, namely duty cycling (DC) and carrier sense multiple access (CSMA), are evaluated independently and in coexisting scenarios, and, also, in the presence of a Long‐Term Evolution (LTE) user equipment. The CSMA protocol analysis shows that very high or very low transmission powers decrease its performance, and thus, either this parameter has to be calibrated or the gateways location has to be adjusted; for the DC protocol, its performance is only affected by the number of gateways within the SRD network, which should be as high as possible. Regarding the coexistence of the DC and CSMA schemes, the results show that CSMA‐based SRDs can successfully operate in the presence of a significant number of DC‐based SRDs, whereas the contrary is not true. Lastly, it is proven that an LTE user equipment may harm the SRD network, although this effect can be mitigated by adjusting the SRDs transmission power; furthermore, the SRDs interference on LTE systems is found to be negligible.
Comparative analysis examining patterns of genomic differentiation across multiple episodes of population divergence in birds
Authors: Delmore Kira E. , Lugo Ramos Juan S. , van Doren Benjamin M. , Lundberg Max , Bensch Staffan , Irwin Darren E. , Liedvogel Miriam 
Published: March 2018

AbstractHeterogeneous patterns of genomic differentiation are commonly documented between closely related populations and there is considerable interest in identifying factors that contribute to their formation. These factors could include genomic features (e.g., areas of low recombination) that promote processes like linked selection (positive or purifying selection that affects linked neutral sites) at specific genomic regions. Examinations of repeatable patterns of differentiation across population pairs can provide insight into the role of these factors. Birds are well suited for this work, as genome structure is conserved across this group. Accordingly, we reestimated relative (FST) and absolute (dXY) differentiation between eight sister pairs of birds that span a broad taxonomic range using a common pipeline. Across pairs, there were modest but significant correlations in window-based estimates of differentiation (up to 3% of variation explained for FST and 26% for dXY), supporting a role for processes at conserved genomic features in generating heterogeneous patterns of differentiation; processes specific to each episode of population divergence likely explain the remaining variation. The role genomic features play was reinforced by linear models identifying several genomic variables (e.g., gene densities) as significant predictors of FST and dXY repeatability. FST repeatability was higher among pairs that were further along the speciation continuum (i.e., more reproductively isolated) providing further insight into how genomic differentiation changes with population divergence; early stages of speciation may be dominated by positive selection that is different between pairs but becomes integrated with processes acting according to shared genomic features as speciation proceeds.
Utilizing cocoyam (Xanthosoma sagittifolium) for food and nutrition security: A review
Authors: Boakye Abena A. , Wireko‐Manu Faustina Dufie , Oduro Ibok , Ellis William O. , Gudjónsdóttir María , Chronakis Ioannis S. 
Published: March 2018

AbstractThe critical role of indigenous crops in the socioeconomic growth of developing nations has necessitated calls for accelerated exploitation of staples. Cocoyam, Xanthosoma sagittifolium, is food for over 400 million people worldwide and is the most consumed aroid in West Africa. However, it remains an underexploited food resource. This study reviews existing literature and also makes use of primary data from interviews with indigenous cocoyam farmers, processors, consumers, and cocoyam scientists in the research Institutes of Ghana, to provide insight into existing nomenclature of the species, indigenous knowledge on food uses, nutritional value, and potential novel food applications of cocoyam. Adaptable technologies in conformity to new trends in food science that could be employed for in‐depth molecular studies and further exploitation of the crop are also discussed. It is envisaged that the provided information would contribute to global efforts aimed at exploiting the full potential of indigenous crops for sustainable food and nutrition security.
Hierarchical network modeling with multidimensional information for aquatic safety management in the cold chain
Authors: Liu Lu , Liu Xinlei , Li Wubin 
Published: March 2018

AbstractThe cold‐chain information has characterized by the loss and dispersion according to the different collecting methods. The description for the quality decay factors of aquatic products can be defined as the multidimensional information. A series of nodes with multidimensional information are assembled to be hierarchies aiming at describing the environment conditions and locations in the supply chain. Each of the single hierarchy levels constitutes a sequence of node information in a network, which is applied as internal information analysis. The cross‐layer information structure is defined as “bridge” information which is able to record the information transmissions among every hierarchy from the point of view of the whole chain. The study has established a novel structured modeling to describe the cold chain of aquatic products based on a network‐hierarchy framework. An organized and sustainable transmission process can be built and recorded by the multidimensional attributes for the whole course of cold chain of aquatic products. In addition, seamless connections among every hierarchy are attainable by the environmental information records continuously to monitor the quality of aquatic products. The quality assessments and shelf life predictions are estimated properly as the risk control in order to monitor and trace the safety of aquatic products under the supply chain perspective.
Green leafy vegetables from two Solanum spp. (Solanum nigrum L and Solanum macrocarpon L) ameliorate scopolamine‐induced cognitive and neurochemical impairments in rats
Authors: Ogunsuyi Opeyemi B. , Ademiluyi Adedayo O. , Oboh Ganiyu , Oyeleye Sunday I. , Dada Abayomi F. 
Published: March 2018

AbstractThis study examined the modulatory effect of Black nightshade (Solanum nigrum L) and African eggplant (Solanum macrocarpon L) leaves on cognitive function, antioxidant status, and activities of critical enzymes of monoaminergic and cholinergic systems of neurotransmission in scopolamine‐administered rats. Cognitive impairment was induced in albino rats pretreated with dietary inclusions of Black nightshade (BN) and African eggplant (AE) leaves by single administration (i.p.) of scopolamine (2 mg/kg body weight). Prior to termination of the experiment, the rats were subjected to spontaneous alternation (Y‐maze) test to assess their spatial working memory. Thereafter, activities of acetylcholinesterase (AChE), butyrylcholinesterase (BChE), monoamine oxidase (MAO), arginase, and antioxidant enzymes (catalase, SOD, and GST) of rat brain homogenate were determined. Also, the malondialdehyde (MDA), nitrite, and GSH contents of the homogenate were determined. The results showed that pretreatment with dietary inclusions of AE and BN significantly reversed the impairment in the rats’ spatial working memory induced by scopolamine. Similarly, elevations in activities of AChE, BChE, and MAO induced by scopolamine were significantly reversed in rats pretreated with dietary inclusions of AE and BN. In addition, impaired antioxidant status induced by scopolamine was reversed by pretreatment with dietary inclusions of AE and BN. This study has shown that dietary inclusions of AE and BN could protect against cognitive and neurochemical impairments induced by scopolamine, and hence, these vegetables could be used as a source of functional foods and nutraceuticals for the prevention and management of cognitive impairments associated diseases such as Alzheimer's disease.
Outdoor physical activity for older people—the senior exercise park: Current research, challenges and future directions
Authors: Levinger Pazit , Sales Myrla , Polman Remco , Haines Terry , Dow Briony , Biddle Stuart J. H. , Duque Gustavo , Hill Keith D. 
Published: March 2018

AbstractIssue addressedExercising outdoors provide beneficial effect on mental and physical health for all ages. However, few older people exercise outdoors other than walking. While outdoor gyms have become increasingly common in Australia, limited outdoor exercise equipment specifically designed for older people is available in public spaces. We have set up and evaluated a unique purpose‐built outdoor exercise park for older people in the community setting and demonstrated positive physical and wellbeing outcomes associated with the provision of this unique exercise mode and social program.MethodsThis study is a reflective narrative describing this innovative exercise approach and reports challenges associated with establishment of the exercise park, conducting the randomised trial, strategies adopted to address these challenges and recommendations for future implementation of this approach in the community.ResultsMany challenges were encountered, including securing appropriate land to locate the exercise park, control of environmental factors for safety (non‐slippery ground and equipment) as well as logistics in running the exercise program itself. Several adjustments in the equipment were also required to ensure safe use by older people.ConclusionThe inclusion of outdoor equipment for older people in public spaces or urban parks is important and careful consideration needs to be taken by local/public authorities to provide access, amenities and safety for all as well as activities to suit all ages.So what?Seniors’ exercise parks can be installed in public places and may provide an enjoyable and effective approach to engage older individuals in a more active and healthier lifestyle.
Decentralisation and health services delivery in Tanzania: Analysis of decision space in planning, allocation, and use of financial resources
Authors: Kigume Ramadhani , Maluka Stephen , Kamuzora Peter 
Published: March 2018

SummaryWhile decentralisation of health systems has been on the policy agenda in low‐income and middle‐income countries since the 1970s, many studies have focused on understanding who has more decision‐making powers but less attention is paid to understand what those powers encompass. Using the decision space approach, this study aimed to understand the amount of decision‐making space transferred from the central government to institutions at the periphery in the decentralised health system in Tanzania. The findings of this study indicated that the decentralisation process in Tanzania has provided authorities with a range of decision‐making space. In the areas of priority setting and planning, district health authorities had moderate decision space. However, in the financial resource allocation and expenditure of funds from the central government, the districts had narrow decision‐making space. The districts, nevertheless, had wider decision‐making space in mobilising and using locally generated financial resources. However, the ability of the districts to allocate and use locally generated resources was constrained by bureaucratic procedures of the central government. The study concludes that decentralisation by devolution which is being promoted in the policy documents in Tanzania is yet to be realised at the district and local levels. The study recommends that the central government should provide more space to the decentralised district health systems to incorporate locally defined priorities in the district health plans.