bluuebunny/crossref_metadata_2025_split huggingface dataset:
Förster Resonance Energy Transfer‐Activated Processes in Smart Nanotheranostics Fabricated in a Sustainable Manner
Authors: Wawrzyńczyk Dominika , Bazylińska Urszula , Lamch Łukasz , Kulbacka Julita , Szewczyk Anna , Bednarkiewicz Artur , Wilk Kazimiera A. , Samoć Marek 
Published: August 2018

AbstractMultilayer nanocarriers loaded with optically activated payloads are gaining increasing attention due to their anticipated crucial role for providing new mechanisms of energy transfers in the health‐oriented applications, as well as for energy storage and environmental protection. The combination of careful selection of optical components for efficient Förster resonance energy transfer, and surface engineering of the nanocarriers, allowed us to synthesize and characterize novel theranostic nanosystems for diagnosis and therapy of deep‐seated tumors. The cargo, constrained within the oil core of the nanocapsules, composed of NaYF4:Tm+3, Yb+3 up‐converting nanoparticles together with a second‐generation porphyrin‐based photosensitizing agent—Verteporfin, assured requisite diagnostic and therapeutic functions under near‐IR laser excitation. The outer polyaminoacid shell of the nanocapsules was functionalized with a ligand—poly(l‐glutamic acid) functionalized by PEG‐ylated folic acid—to ensure both a “stealth” effect and active targeting towards human breast cancer cells. The preparation criteria of all nanocarrier building blocks meet the requirements for sustainable and green chemistry practices. The multifunctionality of the proposed nanocarriers is a consequence of both the surface‐functionalized organic exterior part, which was accessible for selective accumulation in cancer cells, and the hydrophobic optically active interior, which shows phototoxicity upon irradiation within the first biological window.
Tuning Expanded Pores in Metal–Organic Frameworks for Selective Capture and Catalytic Conversion of Carbon Dioxide
Authors: Meng Wei , Zeng Yongfei , Liang Zibin , Guo Wenhan , Zhi Chenxu , Wu Yingxiao , Zhong Ruiqin , Qu Chong , Zou Ruqiang 
Published: August 2018

AbstractThree Co‐based isostructural MOF‐74‐III materials with expanded pores are synthesized, with varied extent of fused benzene rings onto sidechain of same‐length ligands to finely tune the pore sizes to 2.6, 2.4, and 2.2 nm. Gas sorption results for these highly mesoporous materials show that alternately arranged fused benzene rings on one side of the ligand could serve as extra anchoring sites for CO2 molecules with π–π interactions, conspicuously enhancing CO2 uptake and CO2/CH4 and CO2/N2 selectivity; while more steric hindrance effect towards open CoII sites were imposed by ligands flanked with fused benzene rings on both sides, compromising such extra‐sites enhancement. In the catalytic conversion of CO2 with propylene oxide to form propylene carbonate, the as‐synthesized MOF‐74‐III(Co) with desired properties of highly exposed and accessible open CoII centers, large mesopore apertures and multi‐interactive sites, demonstrated higher catalytic activity compared with other two MOFs, with benzene rings fused to ligands hampering the functionality of CoII centers as Lewis acid sites. Our results highlight the viability of finely tuning the expanded pores of MOF‐74 isostructure and the effect of fused benzene rings as functional groups onto selective CO2 capture and conversion.
Investigating the appearance of new psychoactive substances in South Australia using wastewater and forensic data
Authors: Bade Richard , Stockham Peter , Painter Ben , Celma Alberto , Bijlsma Lubertus , Hernandez Felix , White Jason M. , Gerber Cobus 
Published: August 2018

AbstractNew psychoactive substances (NPS) have increased in use and popularity worldwide. Wastewater analysis has been successfully applied to evaluate illicit drugs use within a population. However, for NPS, such an approach may be limited due to low doses of NPS combined with their ever‐changing composition and usage. The dynamic nature of the NPS market means use may be opportunistic, infrequent, and with few users. Hence, the use of complementary information sources is recommended to improve the knowledge on NPS consumption. The aim of this study was to investigate the changing landscape of NPS use on a community scale by combining wastewater analysis and forensic toxicology. Forensic analysis provided specific information on NPS prevalence in post‐mortem blood samples in Adelaide, South Australia over five years, while wastewater analysis showed community use over the same period. A qualitative liquid chromatography–‐high resolution mass spectrometry method was initially used to screen the wastewater samples. A total of 24 NPS were found: 6 in wastewater only, 13 in forensic post‐mortem toxicology samples only, and 5 in both. As these results showed the presence of NPS, a targeted method was subsequently employed to quantify levels of these NPS in wastewater. Temporal trends were found in wastewater with distinct tendencies for synthetic cathinones visible over the period studied.
Seasonal variation of secondary metabolites in nine different bryophytes
Authors: Peters Kristian , Gorzolka Karin , Bruelheide Helge , Neumann Steffen 
Published: August 2018

AbstractBryophytes occur in almost all land ecosystems and contribute to global biogeochemical cycles, ecosystem functioning, and influence vegetation dynamics. As growth and biochemistry of bryophytes are strongly dependent on the season, we analyzed metabolic variation across seasons with regard to ecological characteristics and phylogeny. Using bioinformatics methods, we present an integrative and reproducible approach to connect ecology with biochemistry. Nine different bryophyte species were collected in three composite samples in four seasons. Untargeted liquid chromatography coupled with mass spectrometry (LC/MS) was performed to obtain metabolite profiles. Redundancy analysis, Pearson's correlation, Shannon diversity, and hierarchical clustering were used to determine relationships among species, seasons, ecological characteristics, and hierarchical clustering. Metabolite profiles of Marchantia polymorpha and Fissidens taxifolius which are species with ruderal life strategy (R‐selected) showed low seasonal variability, while the profiles of the pleurocarpous mosses and Grimmia pulvinata which have characteristics of a competitive strategy (C‐selected) were more variable. Polytrichum strictum and Plagiomnium undulatum had intermediary life strategies. Our study revealed strong species‐specific differences in metabolite profiles between the seasons. Life strategies, growth forms, and indicator values for light and soil were among the most important ecological predictors. We demonstrate that untargeted Eco‐Metabolomics provide useful biochemical insight that improves our understanding of fundamental ecological strategies.
Detecting ecological regime shifts from transect data
Authors: Ward Delphi F. L. , Wotherspoon Simon , Melbourne‐Thomas Jessica , Haapkylä Jessica , Johnson Craig R. 
Published: August 2018

AbstractTimely detection of ecological regime shifts is a key problem for ecosystem managers, because changed ecosystem dynamics and function will usually necessitate a change in management strategies. However, currently available methods for detecting regime shifts depend on having multiple long time series data from both before and after the regime shift. This data requirement is prohibitive for many ecosystems. Here, we present a new approach for detecting regime shifts from one‐dimensional spatial (transect) data from just a single time step either side of the transition. Characteristic length scale (CLS) estimation is a method of attractor reconstruction combined with nonlinear prediction that enables identification of the emergent scale at which deterministic behavior of the system is best observed. Importantly, previous studies show that a fundamental change in ecosystem dynamics, from one domain of attraction to another, is reflected in a change in the CLS, i.e., the approach enables distinguishing regime shifts from variability in dynamics around a single attractor. Until now the method required highly resolved two‐dimensional spatial data, but here we adapted the approach so that the CLS can be estimated from one‐dimensional transect data. We demonstrate its successful application to both model and real ecosystem data. In our model test cases, we detected change in the CLS in cases where the shape (topology) of the interaction network had changed, leading to a shift in community composition. In an examination of benthic transect data from four Indonesian coral reefs, changes in the CLS for two of the reefs indicate a regime shift. This new development in estimating CLSs makes it possible to detect regime shifts in systems where data are limited, removing ambiguity in the interpretation of community change.
Managing fishery development in sensitive ecosystems: identifying penguin habitat use to direct management in Antarctica
Authors: Trathan P. N. , Warwick‐Evans V. , Hinke J. T. , Young E. F. , Murphy E. J. , Carneiro A. P. B. , Dias M. P. , Kovacs K. M. , Lowther A. D. , Godø O. R. , Kokubun N. , Kim J. H. , Takahashi A. , Santos M. 
Published: August 2018

AbstractIn the Southern Ocean, the at‐sea distributions of most predators of Antarctic krill are poorly known, primarily because tracking studies have only been undertaken on a restricted set of species, and then only at a limited number of sites. For chinstrap penguins, one of the most abundant krill predators breeding across the Antarctic Peninsula, we show that habitat models developed utilizing the distance from the colony and the bearing to the shelf‐edge, adjusting for the at‐sea density of Pygoscelis penguins from other colonies, can be used to predict, with a high level of confidence, the at‐sea distribution of chinstrap penguins from untracked colonies during the breeding season. Comparison of predicted penguin distributions with outputs from a high‐resolution oceanographic model shows that chinstrap penguins prefer nearshore habitats, over shallow bathymetry, with slow‐flowing waters, but that they sometimes also travel to areas beyond the edge of the continental shelf where the faster‐flowing waters of the Coastal Current or the fronts of the Antarctic Circumpolar Current occur. In the slow‐moving shelf waters, large penguin colonies may lead to krill depletion during incubation and chick‐rearing periods when penguins are acting as central place foragers. The habitats used by chinstrap penguins are also locations preferentially used by the commercial krill fishery, one of the last under‐developed marine capture fisheries anywhere on the planet. As it develops, this fishery has the potential to compete with chinstrap penguins and other natural krill predators. Scaling our habitat models by chinstrap penguin population data demonstrates where overlap with the fishery is likely to be most important. Our results suggest that a better understanding of krill retention and krill depletion in areas used by natural predators and by the krill fishery are needed, and that risk management strategies for the fishery should include assessment of how krill movement can satisfy the demands of both natural predators and the fishery across a range of spatial and temporal scales. Such information will help regional management authorities better understand how plausible ecosystem‐based management frameworks could be developed to ensure sustainable co‐existence of the fishery and competing natural predators.
STEPWAT2: an individual‐based model for exploring the impact of climate and disturbance on dryland plant communities
Authors: Palmquist Kyle A. , Bradford John B. , Martyn Trace E. , Schlaepfer Daniel R. , Lauenroth William K. 
Published: August 2018

AbstractThe combination of climate change and altered disturbance regimes is directly and indirectly affecting plant communities by mediating competitive interactions, resulting in shifts in species composition and abundance. Dryland plant communities, defined by low soil water availability and highly variable climatic regimes, are particularly vulnerable to climatic changes that exceed their historical range of variability. Individual‐based simulation models can be important tools to quantify the impacts of climate change, altered disturbance regimes, and their interaction on demographic and community‐level responses because they represent competitive interactions between individuals and individual responses to fluctuating environmental conditions. Here, we introduce STEPWAT2, an individual plant‐based simulation model for exploring the joint influence of climate change and disturbance regimes on dryland ecohydrology and plant community composition. STEPWAT2 utilizes a process‐based soil water model (SOILWAT2) to simulate available soil water in multiple soil layers, which plant individuals compete for based on the temporal matching of water and active root distributions with depth. This representation of resource utilization makes STEPWAT2 particularly useful for understanding how changes in soil moisture and altered disturbance regimes will concurrently impact demographic and community‐level responses in drylands. Our goals are threefold: (1) to describe the core modules and functions within STEPWAT2 (model description), (2) to validate STEPWAT2 model output using field data from big sagebrush plant communities (model validation), and (3) to highlight the usefulness of STEPWAT2 as a modeling framework for examining the impacts of climate change and disturbance regimes on dryland plant communities under future conditions (model application). To address goals 2 and 3, we focus on 15 sites that span the spatial extent of big sagebrush plant communities in the western United States. For goal 3, we quantify how climate change, fire, and grazing can interact to influence plant functional type biomass and composition. We use big sagebrush‐dominated plant communities to demonstrate the functionality of STEPWAT2, as these communities are among the most widespread dryland ecosystems in North America.
Fish farm effluents are suitable growth media for Nannochloropsis gaditana, a polyunsaturated fatty acid producing microalga
Authors: Dourou Marianna , Tsolcha Olga N. , Tekerlekopoulou Athanasia G. , Bokas Dimitrios , Aggelis George 
Published: August 2018

AbstractFish farm effluents may be used as culture media for marine microalgae, the cell mass of which constitute an excellent fish feed rich in bioactive compounds. In the current investigation different fish farm effluents were tested as culture media for Nannochloropsis strains. Among them, Nannochloropsis gaditana grew well on the effluent released from the sedimentation tank (EST), which is the final step of the wastewater treatment. Mono‐algal but non‐aseptic cultures were conducted in two types of photo‐bioreactors, namely stirred tank reactor (STR) and open pond simulating reactor (OPSR) working under various photoperiods. N. gaditana grew well under full illumination mode on phosphate rich EST in the STR, producing 847.0 mg/L of dry cell mass containing 7.8%, w/w lipids, while when cultivated on phosphate limited EST, cell mass production was slightly lower but lipid biosynthesis was favored, with the lipid content reaching 24.7%, w/w in dry cell mass. In all trials, Nannochloropsis cell mass contained significant quantities of proteins and polysaccharides. Neutral lipids were predominant over polar lipids. Both glycolipid and phospholipid fractions were rich in polyunsaturated fatty acids, especially in eicosapentaenoic acid. We conclude that fish farm wastewaters can be re‐used as microalgae growth media, which is of financial and environmental importance.
CO2—H2O Capture and Cyclability on Sodium Cobaltate at Low Temperatures (30–80 °C): Experimental and Theoretical Analysis
Authors: Vera Elizabeth , Duan Yuhua , Pfeiffer Heriberto 
Published: August 2018

Sodium cobaltate (NaCoO2) is analyzed for the CO2 cyclic carbonation–decarbonation process at low temperatures (30–80 °C) with relative humidity (RH) values between 0% and 80%, using water vapor as a catalytic intermediate. The presence of H2O clearly enhances the CO2 capture at T < 100 °C, compared with dry conditions, where the amount of CO2 captured increases as a function of RH. These improvements are attributed to the formation of NaHCO3 and Na2CO3 during carbonation. In the case of NaHCO3, water vapor becomes a part of carbonation, favoring reactivity. After the carbonation analysis, the decarbonation process is analyzed using a N2 flow, where results evidence that only NaHCO3 decomposition takes place at low temperatures, producing NaOH and CO2. This result indicates that NaCoO2 can be partially regenerated, suggesting a possible CO2 cyclic carbonation. CO2 carbonation–decarbonation tests are performed, confirming the cyclic capacity and stability. Moreover, the NaCoO2 sample is modified by adding different transition metals (Fe, Cu, and Ni) to improve CO2—H2O sorption under similar physicochemical conditions. Results indicate that Fe‐containing samples present the best properties. Finally, the effect of CO2 partial pressure on NaCoO2 and Fe‐containing samples is analyzed using similar RHs.
Spatiotemporal modeling of hydrological return levels: A quantile regression approach
Authors: Franco‐Villoria Maria , Scott Marian , Hoey Trevor 
Published: August 2018

AbstractExtreme river flows can lead to inundation of floodplains, with consequent impacts for society, the environment, and the economy. Extreme flows are inherently difficult to model, being infrequent, irregularly spaced, and affected by nonstationary climatic controls. To identify patterns in extreme flows, a quantile regression approach can be used. This paper introduces a new framework for spatiotemporal quantile regression modeling, where the regression model is built as an additive model that includes smooth functions of time and space, as well as space–time interaction effects. The model exploits the flexibility that P‐splines offer and can be easily extended to incorporate potential covariates. We propose to estimate model parameters using a penalized least squares regression approach as an alternative to linear programming methods, classically used in quantile parameter estimation. The model is illustrated on a data set of flows in 98 rivers across Scotland.
How many measurements are required to construct an accurate sand budget in a large river? Insights from analyses of signal and noise
Authors: Grams Paul E. , Buscombe Daniel , Topping David J. , Kaplinski Matt , Hazel Joseph E. 
Published: August 2018

AbstractMorphological change in river channels is frequently evaluated in the context of mass balance sediment budgets. In a closed sediment budget, measurements of sediment influx and efflux are coupled with measured changes in channel topography to provide both spatial and temporal resolution, and independent estimates of the mass balance. For sediment budgets constructed over long river segments (~102 channel widths or greater) and long periods (~2 years or longer), spatial and temporal accumulation of measurement uncertainty, compounded by inadequate sampling frequency or spatial coverage, may produce indeterminate results. The degree of indeterminacy may be evaluated in the context of a signal‐to‐noise ratio (SNR), which is a function of the magnitude of the mass balance and the magnitudes of potential systematic uncertainties associated with measurements and incomplete sampling. We report on a closed sand budget consisting of measurements of flux and two morphological surveys for a 50‐km segment of a large river over a 3‐year period. Accurate reporting of the magnitude and sign of the change in sand storage was only possible by using state‐of‐the‐art techniques with high temporal frequency and large spatial extent. Together, a sand flux and morphological mass balance revealed that sand evacuation was temporally concentrated (~100% of mass change occurred during 19% of the study period) and highly localized (70% of mass change occurred in 12% of the study segment). A SNR analysis revealed that uncertainty resulting from undersampling may approach or exceed that caused by measurement uncertainty and that daily sampling of suspended‐sand concentration or repeat mapping of at least 50% of the river segment was required to determine the sand budget with SNR > 1. The approach used here to analyze sand budget uncertainty is especially applicable to other river systems with large temporal variability in sediment transport and large spatial variability in erosion and deposition. © 2018 John Wiley & Sons, Ltd.
Temporal coding and rate remapping: Representation of nonspatial information in the hippocampus
Authors: Sanders Honi , Ji Daoyun , Sasaki Takuya , Leutgeb Jill K. , Wilson Matthew A. , Lisman John E. 
Published: August 2018

AbstractHippocampal place cells represent nonspatial information through a process called rate remapping, which involves a change in the firing rate of a place cell without changes in its spatial specificity. However, many hippocampal phenomena occur on very short time scales over which long‐term average firing rates are not an appropriate description of activity. To understand how rate remapping relates to fine‐scale temporal firing phenomena, we asked how rate remapping affected burst firing and trial‐to‐trial spike count variability. In addition, we looked at how rate remapping relates to the theta‐frequency oscillations of the hippocampus, which are thought to temporally organize firing on time scales faster than 100 ms. We found that theta phase coding was preserved through changes in firing rate due to rate remapping. Interestingly, rate remapping in CA1 in response to task demands preferentially occurred during the first half of the theta cycle. The other half of the theta cycle contained preferential expression of phase precession, a phenomenon associated with place cell sequences, in agreement with previous results. This difference of place cell coding during different halves of the theta cycle supports recent theoretical suggestions that different processes occur during the two halves of the theta cycle. The differentiation between the halves of the theta cycle was not clear in recordings from CA3 during rate remapping induced by task‐irrelevant sensory changes. These findings provide new insight into the way that temporal coding is utilized in the hippocampus and how rate remapping is expressed through that temporal code.