bluuebunny/crossref_metadata_2025_split huggingface dataset:
Unraveling the Multistimuli Responses of a Complex Dynamic System of Pseudopeptidic Macrocycles
Authors: Valdivielso Angel M. , Puig‐Castellví Francesc , Atcher Joan , Solà Jordi , Tauler Romà , Alfonso Ignacio 
Published: May 2017

AbstractDynamic combinatorial libraries (DCLs) are excellent benchmark models to study the stimuli‐responsiveness of chemical networks. However, increasingly complex systems are difficult to analyze with simple data analysis methods, because many variables and connections must be considered for their full understanding. Here we propose the use of multivariate data analysis methods to bisect the evolution of a complex synthetic dynamic library of pseudopeptidic macrocycles, containing side chains with charges of different sign. Several stimuli (ionic strength, pH and the presence of a biogenic polyamine) were applied to the same dynamic chemical mixture, and the adaptation of the whole system was characterized by HPLC and analyzed with principal component analysis (PCA) and multivariate curve resolution‐alternating least squares (MCR‐ALS) methods. Both multivariate data analysis chemometric approaches are an excellent combination to extract both qualitative and semi‐quantitative information about the adaptive process of the library upon the action of each stimulus. The resolution of the system with these chemometric tools proved to be especially useful when two inter‐connected stimuli were combined in the same dynamic system. Our results demonstrate the utility of these two approaches for the analysis of complex dynamic chemical systems and open the way toward the application of these powerful tools in the emergent field of systems chemistry.
Structural Dependence of Competitive Adsorption of Water and Methanol on TiO2 Surfaces
Authors: Wang Zhengming , Xiong Feng , Sun Guanghui , Jin Yuekang , Huang Weixin 
Published: May 2017

AbstractEmploying TiO2 anatase (001)‐(1 × 4), rutile (110) and rutile (011)‐(2 × 1) single crystal surfaces, we comprehensively studied the effects of TiO2 surface structures on the competitive adsorption of water and methanol by means of low energy electron diffraction, thermal desorption spectra and X‐ray photoelectron spectroscopy. The relative adsorption strengths of chemisorbed methanol and water vary with the TiO2 surface structures and the adsorption sites. This leads to TiO2 surface structure‐dependent competitive adsorption of water and methanol. The chemisorption of CH3OH on TiO2 anatase (001)‐(1 × 4) surface is seldom affected by pre‐covered water at low coverages but is affected by pre‐covered water at high coverages; the chemisorption of CH3OH on TiO2 rutile (110) surface is seldom affected by pre‐covered water; and the chemisorption of CH3OH on TiO2 rutile (011)‐(2 × 1) surface is affected by pre‐covered water even at low coverages. These results deepen the fundamental understandings of surface chemistry on TiO2 surfaces.
Effect of Sodium on the Structure‐Performance Relationship of Co/SiO2 for Fischer‐Tropsch Synthesis
Authors: Dai Yuanyuan , Yu Fei , Li Zhengjia , An Yunlei , Lin Tiejun , Yang Yanzhang , Zhong Liangshu , Wang Hui , Sun Yuhan 
Published: May 2017

AbstractA series of Co/SiO2 catalysts with different sodium (Na) loadings (0, 0.1, 0.2, 0.5 and 1 wt%) were prepared and evaluated for Fischer‐Tropsch reaction to study the effect of Na on the catalyst structure and catalytic performance. The addition of Na was found to decrease the catalytic activity and hydrocarbon selectivity, but increase CO2 selectivity due to the enhanced WGS activity. The addition of Na also resulted in higher selectivity to oxygenates (alcohols and aldehydes) and O/P ratio as well as the shift of hydrocarbons to lower carbon numbers. Structure characterization revealed a decrease in the surface area and particles size for the calcined samples with the addition of Na. Co2C was formed during the reaction process for the Na‐promoted catalysts. As a result, a new Co/Co2C bifunctional active sites were generated for oxygenates formation leading to increasing oxygenates selectivity. In addition, the Co2C nanoparticles alone may also act as dual active sites for oxygenate formation at high reaction pressure over the promoted catalysts with high Na loading.
Supramolecular Hydrogels of Indole‐Capped Short Peptides as Vaccine Adjuvants
Authors: Wang Zhongyan , Cai Yanbin , Yi Linan , Gao Jie , Yang Zhimou 
Published: May 2017

AbstractMany materials as immune adjuvant are researched to help raise immnogenicity of subunit vaccines. Among them, peptide‐based hydrogels are gradually coming into notice because of their application in drugs delivery, cancer cell inhibition, vaccine adjuvants and detection of important analytes. In this work, we introduced a novel aromatic capping group based on indole to construct short peptide‐based supramolecular hydrogelators Indol‐GFFY and Indol‐GDFDFDY and demonstrated their potential applications as vaccine adjuvants.
Impact of the environment on cancer: Seeing the forest for the trees
Authors: Gomez Scarlett Lin , Shariff‐Marco Salma , Cheng Iona , Reynolds Peggy 
Published: May 2017

The study by Jagai et al. is a valuable resource for researchers to focus on better understanding associations between environmental quality and cancer incidence, as well as for policy makers to target specific regions and environmental factors within those regions to reduce the burden of cancer in the United States. This study also demonstrates the value of environmental geospatial data, a key tool that provides the empirical scientific evidence base to allow scientists to identify disease‐contributing factors and identify vulnerable communities.See also pages 2901‐8.
Color loci placemaking: The urban color between needs of continuity and renewal
Authors: Boeri Cristina 
Published: May 2017

AbstractThe article presents the theoretical framework and the operational concepts of a research, finalized to explore and verify the prerequisites of an approach to urban color that, while recognizing to color the flexible as well as transient capacity to respond to the successive and multiple demands that characterize the urban space, sees a possible way of coexisting between the needs of continuity and renewal. Searching to understand the modalities and possibilities through which colour can intervene in the processes of transformation of the city to support both the needs of resignification and reappropriation and those of conservation and enhancement of the vital identity of each single place, the research looked on one side to the experiences gained within the colour plans and Lenclos' geography of colour and on the other side to the different and diversified experiences developed within the idea and practice of placemaking, aimed at the recognition and enhancement of the collective and plural creative dimension that colour seems effectively able to interpret. The term “color loci placemaking” was introduced to summarize this mode/possibility of understanding and approaching urban color, characterized especially by the attention for the specificity of each single place and the human factor underpinning place‐experience.
Influence of vehicle on historical pigments colour
Authors: Gueli Anna M. , Pasquale Stefania , Troja Sebastiano O. 
Published: May 2017

AbstractThe colour of a paint layer is determined by the pigments mixed with a vehicle and painted on a support. According to their chemical nature, the vehicles are substances that, after drying or hardening, produce an uniform and homogeneous layer. With the aim of quantifying the influence of the medium on the specification of the painting colour, we realized samples of paintings. We considered pigments and dyes of the artist's hues using the vehicles typical of ancient times: oils (especially linseed and poppy oils), casein and egg yolk, mixed according to old recipes. Measurements were performed by reflectance spectrophotometry observing the Spectral Reflectance Factor (%SRF) trend and calculating colour changes. The colorimetric study was carried out in the CIELAB colour space related to the CIE 1964 standard observer and with the D65 illuminant. The results were evaluated also on the basis of the distribution of pigment particles on paint layers observed by scanning electron microscopy.
Methyl Internal Rotation in the Microwave Spectrum of o‐Methyl Anisole
Authors: Ferres Lynn , Mouhib Halima , Stahl Wolfgang , Nguyen Ha Vinh Lam 
Published: May 2017

AbstractThe microwave spectrum of o‐methyl anisole (2‐methoxytoluene), CH3OC6H4CH3, has been measured by using a pulsed molecular jet Fourier transform microwave spectrometer operating in the frequency range 2–26.5 GHz. Conformational analysis using quantum chemical calculations at the MP2/6–311++G(d,p) level of theory yields only one stable conformer with a Cs structure, which was assigned in the experimental spectrum. A–E splittings due to the internal rotation of the ring methyl group could be resolved and the barrier to internal rotation was determined to be 444.05(41) cm−1. The experimentally deduced molecular parameters such as rotational and centrifugal distortion constants as well as the torsional barrier of the ring methyl group are in agreement with the calculated values.
Rational Design of Stable Dianions by Functionalizing Polycyclic Aromatic Hydrocarbons
Authors: Zhong Mingmin , Zhou Jian , Jena Puru 
Published: May 2017

AbstractUsing density functional theory, we have carried out a systematic study of the stability and electronic properties of neutral and multiply charged molecules BnC10‐nX8 (n=0, 1, 2; X=H, F, CN). Our main objective is to explore if the replacements of core C atoms and/or H atoms in naphthalene (C10H8) can enhance the stability of their dianions. Indeed, we find that the dianions of BnC10‐n(CN)8 are more stable than their monoanions with energies of 0.61 eV, 0.57 eV, and 1.97 eV for n=0, 1, 2, respectively. In addition, polycyclic aromatic hydrocarbons become stable as dianions only when H atoms are substituted by more electronegative species. Thus, a rational design approach by tailoring composition and ligands can lead to a new class of organic molecules that are capable of carrying multiple charges.
The Bound Structures of 17β‐Estradiol‐Binding Aptamers
Authors: Hilder Tamsyn A. , Hodgkiss Justin M. 
Published: May 2017

AbstractDNA aptamers can exhibit high affinity and selectivity towards their targets, but the aptamer–target complex structures are rarely available from crystallography and often difficult to elucidate. This is particularly true of small molecule targets, including 17β‐estradiol (E2), which is becoming one of the most widely encountered endocrine‐disrupting chemicals in the environment. Using molecular dynamics simulations, we demonstrate that E2 binds to a thymine loop region common to all E2‐specific aptamers in the literature. Analyzing these structures allows us to design new E2 binding sequences. As well as illuminating the essential sequence and structural factors for generating specificity for E2, we demonstrate the effectiveness of molecular dynamics simulations for aptamer science.
Pollution‐tolerant invertebrates enhance greenhouse gas flux in urban wetlands
Authors: Mehring Andrew S. , Cook Perran L. M. , Evrard Victor , Grant Stanley B. , Levin Lisa A. 
Published: May 2017

AbstractOne of the goals of urban ecology is to link community structure to ecosystem function in urban habitats. Pollution‐tolerant wetland invertebrates have been shown to enhance greenhouse gas (GHG) flux in controlled laboratory experiments, suggesting that they may influence urban wetland roles as sources or sinks of GHG. However, it is unclear if their effects can be detected in highly variable conditions in a field setting. Here we use an extensive data set on carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) flux in sediment cores (n = 103) collected from 10 urban wetlands in Melbourne, Australia during summer and winter in order to test for invertebrate enhancement of GHG flux. We detected significant multiplicative enhancement effects of temperature, sediment carbon content, and invertebrate density on CH4 and CO2 flux. Each doubling in density of oligochaete worms or large benthic invertebrates (oligochaete worms and midge larvae) corresponded to ~42% and ~15% increases in average CH4 and CO2 flux, respectively. However, despite exceptionally high densities, invertebrates did not appear to enhance N2O flux. This was likely due to fairly high organic carbon content in sediments (range 2.1–12.6%), and relatively low nitrate availability (median 1.96 μmol/L NO3−‐N), which highlights the context‐dependent nature of community structural effects on ecosystem function. The invertebrates enhancing GHG flux in this study are ubiquitous, and frequently dominate faunal communities in impaired aquatic ecosystems. Therefore, invertebrate effects on CO2 and CH4 flux may be common in wetlands impacted by urbanization, and urban wetlands may make greater contributions to the total GHG budgets of cities if the negative impacts of urbanization on wetlands are left unchecked.
Arbuscular mycorrhizal colonization has little consequence for plant heavy metal uptake in contaminated field soils
Authors: Dietterich Lee H. , Gonneau Cédric , Casper Brenda B. 
Published: May 2017

AbstractThe factors affecting plant uptake of heavy metals from metalliferous soils are deeply important to the remediation of polluted areas. Arbuscular mycorrhizal fungi (AMF), soil‐dwelling fungi that engage in an intimate exchange of nutrients with plant roots, are thought to be involved in plant metal uptake as well. Here, we used a novel field‐based approach to investigate the effects of AMF on plant metal uptake from soils in Palmerton, Pennsylvania, USA contaminated with heavy metals from a nearby zinc smelter. Previous studies often focus on one or two plant species or metals, tend to use highly artificial growing conditions and metal applications, and rarely consider metals’ effects on plants and AMF together. In contrast, we examined both direct and AMF‐mediated effects of soil concentrations on plant concentrations of 8–13 metals in five wild plant species sampled across a field site with continuous variation in Zn, Pb, Cd, and Cu contamination. Plant and soil metal concentration profiles were closely matched despite high variability in soil metal concentrations even at small spatial scales. However, we observed few effects of soil metals on AMF colonization, and no effects of AMF colonization on plant metal uptake. Manipulating soil chemistry or plant community composition directly may control landscape‐level plant metal uptake more effectively than altering AMF communities. Plant species identities may serve as highly local indicators of soil chemical characteristics.
Conservation of wildlife populations: factoring in incremental disturbance
Authors: Stewart Abbie , Komers Petr E. 
Published: May 2017

AbstractProgressive anthropogenic disturbance can alter ecosystem organization potentially causing shifts from one stable state to another. This potential for ecosystem shifts must be considered when establishing targets and objectives for conservation. We ask whether a predator–prey system response to incremental anthropogenic disturbance might shift along a disturbance gradient and, if it does, whether any disturbance thresholds are evident for this system. Development of linear corridors in forested areas increases wolf predation effectiveness, while high density of development provides a safe‐haven for their prey. If wolves limit moose population growth, then wolves and moose should respond inversely to land cover disturbance. Using general linear model analysis, we test how the rate of change in moose (Alces alces) density and wolf (Canis lupus) harvest density are influenced by the rate of change in land cover and proportion of land cover disturbed within a 300,000 km2area in the boreal forest of Alberta, Canada. Using logistic regression, we test how the direction of change in moose density is influenced by measures of land cover change. In response to incremental land cover disturbance, moose declines occurred where <43% of land cover was disturbed; in such landscapes, there were high rates of increase in linear disturbance and wolf density increased. By contrast, moose increases occurred where >43% of land cover was disturbed and wolf density declined. Wolves and moose appeared to respond inversely to incremental disturbance with the balance between moose decline and wolf increase shifting at about 43% of land cover disturbed. Conservation decisions require quantification of disturbance rates and their relationships to predator–prey systems because ecosystem responses to anthropogenic disturbance shift across disturbance gradients.
Truffle biogeography—A case study revealing ecological niche separation of different Tuber species
Authors: Gryndler Milan , Šmilauer Petr , Šťovíček Václav , Nováková Kristýna , Hršelová Hana , Jansa Jan 
Published: May 2017

AbstractEcology of hypogeic mycorrhizal fungi, such as truffles, remains largely unknown, both in terms of their geographical distribution and their environmental niches. Occurrence of true truffles (Tuber spp.) was therefore screened using specific polymerase chain reaction (PCR) assays and subsequent PCR amplicon sequencing in tree roots collected at 322 field sites across the Czech Republic. These sites spanned a wide range of climatic and soil conditions. The sampling was a priori restricted to areas thought to be suitable for Tuber spp. inasmuch as they were characterized by weakly acidic to alkaline soils, warmer climate, and with tree species previously known to host true truffles. Eight operational taxonomic units (OTUs) corresponding to Tuber aestivum, T. borchii, T. foetidum, T. rufum, T. indicum, T. huidongense, T. dryophilum, and T. oligospermum were detected. Among these, T. borchii was the OTU encountered most frequently. It was detected at nearly 19% of the sites. Soil pH was the most important predictor of Tuber spp. distribution. Tuber borchii preferred weakly acidic soils, T. foetidum and T. rufum were most abundant in neutral soils, and T. huidongense was restricted to alkaline soils. Distribution of T. aestivum was mainly dictated by climate, with its range restricted to the warmest sites. Host preferences of the individual Tuber spp. were weak compared to soil and climatic predictors, with the notable exception that T. foetidum appeared to avoid oak trees. Our results open the way to better understanding truffle ecology and, through this new knowledge, also to better‐informed trufficulture.
Using regional bird density distribution models to evaluate protected area networks and inform conservation planning
Authors: Alexander John D. , Stephens Jaime L. , Veloz Sam , Salas Leo , Rousseau Josée S. , Ralph C. John , Sarr Daniel A. 
Published: May 2017

AbstractAs data about populations of indicator species become available, proactive strategies that improve representation of biological diversity within protected area networks should consider finer‐scaled evaluations, especially in regions identified as important through course‐scale analyses. We use density distribution models derived from a robust regional bird abundance dataset, coupled with habitat conservation plans, to evaluate a network of protected areas and to inform conservation and biodiversity planning in the greater Klamath Siskiyou Bioregion, an area recognized globally as a region of outstanding biological diversity. Our novel modeling approach allowed for comparisons of abundance of conservation focal species on federal vs. non‐federal lands, federal lands that are protected to maintain natural habitats vs. federal lands managed for multiple uses, and seven protected areas of interest. Our comparisons highlight conservation opportunities for suites of species associated with coniferous forests, oak woodlands, and grasslands. Specifically, we found that species associated with oak woodland and grassland habitats, both habitats of conservation concern, were not well represented in the Bioregion's existing protected areas. These species would benefit from expanding the regional protected area network to include their associated at‐risk habitats. In contrast, our results suggest that coniferous forests birds are well represented in the Bioregion's protected areas. We identify management opportunities specifically associated with the restoration of fire‐adapted ecosystems that would benefit coniferous forest focal species on both federally protected areas and other multiple‐use lands. Our analysis provides an example of how a finer‐scaled evaluation of a regional protected area network adds value to course‐scale evaluations of protected areas and biological diversity. Data and results from this research were used to inform science‐based expansion of the Bioregion's network of protected areas.
Crystal Growth and Characterization of the Mixed‐Cation Rb+/[XeF5]+ and Cs+/[XeF5]+ Salts
Authors: Mazej Zoran , Goreshnik Evgeny 
Published: May 2017

AbstractInvited for the cover of this issue is research led by Zoran Mazej in collaboration with Evgeny Goreshnik, both from the Jožef Stefan Institute, Ljubljana, Slovenia. The cover image shows the formation of a new type of noble gas coordination compounds A[XeF5][MF6]2 (A = Rb, Cs; M = Sb, Bi) that crystallize in two modifications.
Membranes with a low loading of Metal–Organic Framework‐Supported Ionic Liquids for CO2/N2 separation in CO2 capture
Authors: Monteiro Bernardo , Nabais Ana Rita , Almeida Paz Filipe A. , Cabrita Luis , Branco Luis C. , Marrucho Isabel M. , Neves Luisa A. , Pereira Cláudia C. L. 
Published: May 2017

AbstractImmobilization of ionic liquids (ILs) into 3D metal–organic frameworks (MOFs) is reported. The incorporation of these composites in a polyimide‐based matrix (Matrimid® 5218) to yield [IL@MOF]@Matrimid® 5218 is an efficient strategy to improve the permeability and selectivity toward CO2/N2 mixtures, presenting also a remarkable improvement in membrane flexibility and mechanical resistance. Using MOF‐5, a crystalline phase different to its original phase is obtained after the incorporation of hydrated IL without loss of adsorptive properties.
Catalytic oxidative degradation of 4‐chlorophenol: Effect of operating parameters and prediction of intermediates/by‐products
Authors: Singh Swati , Garg Anurag 
Published: May 2017

The presence of chlorophenols (CP) in industrial wastewater is a major concern due to their microbial toxicity. The present study was performed to investigate the efficacy of advanced oxidation process (i.e., conventional and modified Fenton's process) for the degradation of 4‐chlorophenol (4‐CP) in an aqueous solution (concentration = 200 mg L−1) under varying reaction conditions. The decomposition of 4‐CP was confirmed by chemical oxygen demand (COD) reduction, total organic carbon (TOC) reduction, detection of low molecular weight carboxylic acids (such as oxalic, acetic, formic and malonic) and Cl‐ concentration in the treated 4‐CP aqueous solution. The maximum COD and TOC reductions were 74% and 42% after 30 min of Fenton reaction at an initial pH, Fe2+ concentration, and H2O2 to Fe2+ molar ratio of 3.0, 1.26 mM and 20, respectively which were found to increase to 79 and 55%, respectively when Cu2+ was also added with Fe2+ during modified Fenton process. © 2017 American Institute of Chemical Engineers Environ Prog, 36: 1734–1742, 2017