bluuebunny/crossref_metadata_2025_split huggingface dataset:
Cu/C‐catalyzed Hydrogenolysis of Sorbitol to Glycols–On the Influence of Particle Size and Base
Authors: Wang Xinde , Beine Anna Katharina , Hausoul Peter J. C. , Palkovits Regina 
Published: April 2019

AbstractHerein, a series of Cu catalysts supported on activated carbon with increasing particle size was tested for the conversion of sorbitol to glycols including 1,2‐propanediol and ethylene glycol in the presence of Ca(OH)2. Activity measurements reveal a distinct correlation between TOF and particle size, which increases until 14 nm (N2O chemisorption based) after which a plateau is reached. However, variation of the particle size has no apparent effect on the selectivity for C3/C3 and C2/C4 cleavage. In contrast, variation of the Ca(OH)2 equivalence has a profound impact on selectivity. The ratio of C3/(C2+C4) products reaches an optimum at 0.45 equiv. of Ca(OH)2. Notably, the time course of the reaction demonstrates that the by‐products lactic acid and glycerol are in‐situ converted to the desired product 1,2‐propanediol, contributing to the unprecedented combined glycol selectivity of 84.5 % at 513 K, 5 MPa H2 and 0.3 equiv. of Ca(OH)2. Furthermore, recycling tests reveal a rapid deactivation which is attributed to aggregation of Cu observed in TEM.
Experimental studies on joinability of zircaloy and SiC/SiC composite with titanium powder
Authors: Serizawa Hisashi , Nakazato Naofumi , Sato Yuji , Tsukamoto Masahiro , Park Joon‐Soo , Kishimoto Hirotatsu 
Published: April 2019

AbstractAs for the enhanced accident tolerant fuel cladding for the advanced light‐water reactor, silicon carbide fiber reinforced silicon carbide matrix composite (SiC/SiC composite) is expected as a potential replacement of the current Zircaloy fuel cladding due to its many superiorities, where it is a key issue to develop the endcap seal of SiC/SiC composite cladding. In this research, based on the calking method, the fiber laser irradiation method was employed for sealing the endcap of SiC/SiC composite tube by Zircaloy tube, where the titanium micro‐powder was packed in the slit manufactured on the outer surface of SiC/SiC composite tube. By applying the laser beam irradiation to the outer surface of Zircaloy tube circumferentially, the mechanical calking joint was successfully fabricated. In addition, it is revealed that the good adhesion between Zircaloy and SiC/SiC composite was partially produced as the result of the generation of all proportional solid solution between titanium and zirconium. Moreover, the examinations about the slit shape influences indicate that the narrow hook slit seems to be the best type of silt for holding the titanium powder during the laser irradiation, where the width of slit should be narrower than that of laser irradiation line.
Making Use of the Direct Process Residue: Synthesis of Bifunctional Monosilanes
Authors: Sturm Alexander G. , Santowski Tobias , Schweizer Julia I. , Meyer Lioba , Lewis Kenrick M. , Felder Thorsten , Auner Norbert , Holthausen Max C. 
Published: April 2019

AbstractThe industrial production of monosilanes MenSiCl4−n (n=1–3) through the Müller–Rochow Direct Process generates disilanes MenSi2Cl6−n (n=2–6) as unwanted byproducts (“Direct Process Residue”, DPR) by the thousands of tons annually, large quantities of which are usually disposed of by incineration. Herein we report a surprisingly facile and highly effective protocol for conversion of the DPR: hydrogenation with complex metal hydrides followed by Si−Si bond cleavage with HCl/ether solutions gives (mostly bifunctional) monosilanes in excellent yields. Competing side reactions are efficiently suppressed by the appropriate choice of reaction conditions.
Synergy of Anodic Oxidation and Cathodic Reduction Leads to Electrochemical C—H Halogenation
Authors: Zhou Zhilin , Yuan Yong , Cao Yangmin , Qiao Jin , Yao Anjin , Zhao Jing , Zuo Wanqing , Chen Wenjie , Lei Aiwen 
Published: April 2019

Summary of main observation and conclusionWe herein uncovered an electrochemical C—H halogenation protocol that synergistically combines anodic oxidation and cathodic reduction for C—X bond formation. The reaction was demonstrated under exogenous‐oxidant‐free conditions. Moreover, this is the first example of activating CBr4, CHBr3, and CCl3Br under electrochemical conditions.
Aging of polymeric materials by stray‐field NMR relaxometry with the NMR‐MOUSE
Authors: Blümich Bernhard 
Published: April 2019

AbstractThe sensitivity of NMR relaxation to molecular motion is explored to study the aging of polymer materials and paint binder in master paintings. Polymeric materials are formulated from macromolecules with a distribution of molecular weights and low molecular weight additives. Their physical and chemical properties change with time due to exposure to temperature, mechanical stress, and solvents. These conditions lead to physical and chemical aging, which can proceed naturally over longer times or accelerated under artificial conditions in shorter times. Either procedure bears a particular signature on the molecular mobility, which can be probed nondestructively by the NMR relaxation times T1 and T2. Natural aging and accelerated temperature‐ and solvent‐induced aging are summarized for synthetic polymer materials and compared to aging of binders in the paint layers of paintings aged naturally over hundreds of years and aged artificially by solvent‐cleaning procedures during restoration or at elevated temperature during forgery.
The past, present, and future of 1.26T2
Authors: Rovnyak David 
Published: April 2019

AbstractThis mini‐review considers the scientific and historical development of the constant 1.26T2, which represents the acquisition time for which the signal‐to‐noise ratio of a decaying exponential (with time constant T2) is a maximum in the presence of thermal noise. While first reported in 1977, interest in this result greatly increased after about the year 2000, when it began to influence thinking in nonuniform sampling, sensitivity, and pulse sequence design. Overall, 1.26T2 has become a lens through which to view the evolution of NMR data acquisition and processing. An enduring lesson of the 1.26T2 story is the value of describing and analyzing the properties of magnetic resonance signals in the time domain prior to any further spectral analysis and processing, a concept which is at the core of many modern analytic techniques.
Associations of visual forms with colors: The minor role of emotion as the mediator
Authors: Hanada Mitsuhiko 
Published: April 2019

AbstractAssociations of colors with a wide variety of visual forms were examined. Fifty visual forms were presented to Japanese participants, who were asked to report a color suitable to each visual form out of 15 colors. Correspondence analysis was applied to the responses, and four dimensions of configurations were obtained. The first and second dimensions were related to chromaticity or hue. In these dimensions, red and orange were associated with round symmetric shapes, yellow with shapes with sharp corners, violet and purple with irregular shapes with smooth curves, and cold colors such as blue and green with forms that consisted of simple geometrical elements such as triangles, squares, and circles. The third dimension was related to L* and b* in the CIELAB color space and to the stability of visual forms. Dimension 4 was not significantly related to any of L*, a*, and b*. In another experiment, participants rated the affective impressions of the colors and visual forms on semantic differential (SD) scales. The analyses of the SD data combined with the results of the color‐form associations suggest that the role of emotional meanings of colors and visual forms in mediating the associations was rather minor, and that world‐knowledge contributed considerably to the observed color‐form associations. Kandinsky's color‐form assignment was also examined, and except for the yellow‐triangle association, the assignment was not supported.
Particle Swarm Optimization (PSO) with fuzzy c means (PSO‐FCM)–based segmentation and machine learning classifier for leaf diseases prediction
Authors: S.K. Pravin Kumar , Sumithra M.G. , Saranya N. 
Published: April 2019

SummaryThis paper proposes an automatic classification technique that uses leaf images some medicinal plants. It is primarily the core reason that drives the research presented here, including the introduction of new innovative segmentation and classification techniques that are deployed to facilitate automatic detection. The major aim of the work is to introduce a new leaf disease prediction technique. The study conducted here a unique but effective image segmentation, feature extraction, as well as plant leaf disease classification. The proposed approach initially preprocesses leaf images of plants thereafter which the diseased sections of the plant are segmented by deploying Particle Swarm Optimization (PSO)–based fuzzy c means segmentation (PSO‐FCM), Gaussian Mixture Model (GMM)–based background subtraction. Vein and shape features, edge‐based feature extraction, and texture characteristics or texture features (TF) are computed. This methodology classifies the leaves of medicinal plants by deploying the Multiple Kernel Parallel Support Vector Machine (MK‐PSVM) classifier. The classifier is implemented via the use of MATLAB classifier. The results are measured using the accuracy, sensitivity, specificity, precision, and F‐measure metrics. Experimental results depict that the classifiers that have been proposed here achieve a higher classification accuracy enabling leaf detection.
Determination of Dermal Pharmacokinetics by Microdialysis Sampling in Rats
Authors: Voelkner Nivea M. F. , Voelkner Alexander , Derendorf Hartmut 
Published: April 2019

AbstractThe evaluation of absorption and availability at the site of action of a drug candidate is an important element of drug discovery and development, as clinical response is a function of the bioavailability of the active agent and its continued presence at the site of action. Evaluation of dermal pharmacokinetics facilitates the selection of new compounds or chemical structures for advancement as possible clinical candidates. An advantage of microdialysis is that it allows the measurement of compound concentrations at the site of action without disturbing the tissue milieu, making it possible to determine the relationship between this important variable and plasma concentrations of the agent. Described in this unit are laboratory protocols for performing dermal microdialysis experiments in rat for the purpose of defining the pharmacokinetics parameters of test agents. © 2019 by John Wiley & Sons, Inc.
A Semisynthetic Peptide−Metalloporphyrin Responsive Matrix for Artificial Photosynthesis
Authors: Sun Zhongwu , Diebolder Christoph A. , Renault Ludovic , de Groot Huub 
Published: April 2019

AbstractThe CsmA protein from the baseplate of theChlorobaculum tepidumis proposed as an attractive motif for the engineering of semisynthetic materials for artificial photosynthesis. We perform self‐assembly of zinc protoporphyrin IX (ZnPP) with a truncated CsmA (tCsmA) amphipathic peptide scaffold for the bottom‐up construction of a semisynthetic matrix for energy transfer. The resulting self‐assembly shows an extended periodic structure with 72helical symmetry. The complex is able to maintain a good photostability for at least 30 min when the concentration is more than 20 μM, and almost 100 % harvested energy can be transferred to the acceptor cation radical methyl viologen (MV+). The excitation‐energy transfer rate of the complex was increased from the ns−1scale to the ps−1scale that is comparable to natural light‐harvesting antenna systems. It contributes to converging evidence that chiral responsive matrix assemblies can be developed for efficient light energy harvesting in artificial photosynthesis.
Socially responsible investing and the performance of Eurozone corporate bond portfolios
Authors: Pereira Patrícia , Cortez Maria Céu , Silva Florinda 
Published: April 2019

AbstractThis paper investigates the performance of socially screened bond portfolios of 189 Eurozone companies between 2003 and 2016. Bond portfolios are formed on the basis of an aggregate measure of corporate social responsibility (CSR) and on specific dimensions of CSR, namely, Environment, Social, and Governance dimensions. Our results show that the performance of highly socially rated bonds is not significantly different from that of low‐rated bonds. We also observe that in an earlier stage, portfolios of high‐rated bonds outperformed portfolios of low‐rated bonds. Yet over time, this outperformance disappears. These results suggest that the errors‐in‐expectations and shunned‐security hypotheses are not only useful in explaining the performance of socially responsible equity portfolios but that they are also useful in explaining the performance of socially screened bond portfolios over time. Overall, our results indicate that investors can form bond portfolios based on sustainability criteria without compromising financial performance.
An enhanced whale optimization algorithm for vehicular communication networks
Authors: Valayapalayam Kittusamy Senthil Ragavan , Elhoseny Mohamed , Kathiresan Shankar 
Published: April 2019

SummaryIn the field of vehicle communication networks, vehicular ad hoc network (VANET) is established with the help of road side unit (RSU). Each vehicle in the traffic system is managed by RSU with certain mobility factor, but still, there are some issues in the mobility management. In order to avoid such expensive RSUs and to enhance the mobility management of VANET system, the paper proposes a novel algorithm for the process of organizing a cluster structure and cluster head (CH) election suitable for VANETs. The proposed adaptive weighted clustering protocol (AWCP) groups the random nodes, and then the optimal CH is attained by the optimization of network parameters. For the purpose of optimization, an innovative algorithm called the enhanced whale optimization algorithm (EWOA) is introduced. For each vehicle in a trusted clustering model, its movement is analyzed by vehicle network mobility routing protocol with identified speed and position. The distance between the trusted vehicle node and RSU is analyzed by the proposed AWCP‐EWOA model. The results demonstrate the proposed AWCP‐EWOA model outperforms compared with AWCP and AWCP‐Whale Algorithm (WA) protocols in terms of clustering efficiency and its mobility enhancement.
Identity of coral reef herbivores drives variation in ecological processes over multiple spatial scales
Authors: Ruttenberg Benjamin I. , Adam Thomas C. , Duran Alain , Burkepile Deron E. 
Published: April 2019

AbstractOverexploitation of key species can negatively impact ecosystem processes, so understanding the ecological roles of individual species is critical for improving ecosystem management. Here, we use coral reefs and the process of herbivory as a model to examine how species identity of consumers influence ecosystem processes to inform management of these consumers. Herbivorous fishes can facilitate the recruitment, growth, and recovery of corals by controlling the fast‐growing algae that can outcompete corals for space. However, herbivorous fish guilds are species rich with important differences among species in diet, movement, and habitat preferences. Yet, we lack a general understanding of (1) how these species‐specific differences in feeding and behavior scale up to reef‐wide rates of ecosystem processes and (2) how species identity and diversity impact these processes. To address these knowledge gaps, we used field observations to derive key species‐ and size‐specific foraging parameters for nine herbivorous parrotfish species on coral reefs in the Florida Keys, USA. We then combined these foraging parameters with fish survey data spanning multiple spatial scales to estimate the rates of three ecosystem processes: area of reef grazed, amount of macroalgae removed, and rate of bioerosion. We found that predicted rates of ecological processes varied dramatically among habitats and among reef zones within habitats, driven primarily by variation in abundance among species with different foraging behaviors. In some cases, assemblages with similar levels of total biomass had different rates of ecological processes, and in others, assemblages with different biomass had similar rates of ecological processes. Importantly, our models of herbivory using species‐specific parameters differed from those using genus‐level parameters by up to 300% in rates of ecological processes, highlighting the importance of herbivore identity in this system. Our results indicate that there may be little overlap in the roles species play, suggesting that some systems may be vulnerable to loss of ecological function with the reduction or loss of just a few species. This work provides a framework that can be applied across the region to predict how changes in management may affect the ecological impact of these important herbivores.
A population genetics perspective on the evolutionary histories of three clonal, endemic, and dominant grass species of the Qinghai–Tibet Plateau: Orinus (Poaceae)
Authors: Liu Yuping , Harris AJ , Gao Qingbo , Su Xu , Ren Zhumei 
Published: April 2019

AbstractWe performed analyses of amplified fragment length polymorphism (AFLP) in order to characterize the evolutionary history of Orinus according to its population genetic structure, as well as to investigate putative hybrid origins of O. intermedius and to provide additional insights into relationships among species. The genus Orinus comprises three clonal grasses that are dominant species within xeric alpine grasslands of the Qinghai–Tibet Plateau (QTP). Here, we used eight selectively obtained primer pairs of EcoRI/MseI to perform amplifications in 231 individuals of Orinus representing 48 populations and all three species. We compared our resulting data to genetic models of hybridization using a Bayesian algorithm within NewHybrids software. We determined that genetic variation in Orinus was 56.65% within populations while the among‐species component was 30.04% using standard population genetics statistics. Nevertheless, we detected that species of Orinus were clustered into three highly distinct genetic groups corresponding to classic species identities. Our results suggest that there is some introgression among species. Thus, we tested explicit models of hybridization using a Bayesian approach within NewHybrids software. However, O. intermedius likely derives from a common ancestor with O. kokonoricus and is probably not the result of hybrid speciation between O. kokonoricus and O. thoroldii. We suspect that recent isolation of species of Orinus in allopatry via vicariance may explain the patterns in diversity that we observed, and this is corroborated by a Mantel test that showed significant positive correlation between geographic and genetic distance (r = 0.05, p < 0.05). Recent isolation may explain why Orinus differs from many other clonal species by exhibiting the highest diversity within populations rather than among them.
Functional differences stabilize beetle communities by weakening interspecific temporal synchrony
Authors: van Klink Roel , Lepš Jan , Vermeulen Rikjan , de Bello Francesco 
Published: April 2019

AbstractThe temporal stability of communities is essential for the maintenance of ecosystem functioning across trophic levels. The stabilizing effect of biodiversity is, among other factors, modulated by the level of synchrony in population fluctuations among the species in the community. What drives community synchrony, however, remains largely unclear. Community synchrony can be affected by external drivers such as disturbances, but also by the properties of the community. Species with different ecological strategies should fluctuate less synchronously than more similar species; thus, an increase in diversity of ecological strategies should decrease synchrony, and increase the stability of the community. Here, using an exceptionally large data set of ground beetle trappings in Dutch heathlands (~370,000 individuals in 19 plots, each sampled between 9 and 36 yr), we assess the drivers of community stability and synchrony, and their relationship with disturbance, species richness, and functional diversity (FD). We found no effect of disturbance (fire and topsoil removal) on community stability or synchrony, probably because of unpredictable patterns of increase or decrease of the populations. Community synchrony was overall positive, giving more support for independent and positive correlation between species than for compensatory dynamics. Synchrony decreased with increasing FD, but not with species richness. Supporting this, we found that the more species pairs differ in their traits, the less synchronously their populations fluctuate, where 74% of all pairs showed no significant correlation. Significant positive synchrony (19% of species pairs) was concentrated among pairs with low trait dissimilarity, and the 7% of pairs with significant negative temporal correlation showed no relation with pairwise functional dissimilarity. The stabilizing effect of FD via decreased synchrony supports largely untested theoretical expectations that an increased diversity of functional strategies in a community will have a stabilizing effect on community abundance. We hypothesize that because competition is low in this community, the stabilizing effect of FD reflects interspecific variation in responses to environmental fluctuations rather than competition.
A G‐quadruplex/hemin DNAzyme‐based microchip electrophoresis chemiluminescence assay for highly sensitive detection of biotin in flour
Authors: Li Jian , Li Shuting , Zhao Jingjin , Huang Yong , Zhao Shulin 
Published: April 2019

AbstractQuantitative analysis of biotin in biological fluids, foods, and pharmaceutical is important for diagnosis and treatment of biotin‐related diseases and health maintenance. In this work, a novel G‐quadruplex/hemin DNAzyme‐based microchip electrophoresis chemiluminescence (CL) assay method was established for rapid and highly sensitive detection of biotin. This method is based on the specific binding between biotin and streptavidin, the catalytic CL characteristics of G‐quadruplex/hemin DNAzyme to the oxidation–reduction reaction of hydrogen peroxide with luminol, and the on‐line separation function of microchip electrophoresis. Under the optimal experimental conditions, on‐chip biotin analysis was achieved within 1 min. The CL intensity is linearly proportional to the concentration of biotin in the range of 13–630 nM with a detection limit of 6.4 nM. The proposed method has been applied for the detection of biotin in flour, biotin contents in three flour samples are found in the range of 199–223 ng/g with a mean value of 214 ng/g. The recoveries were in the range of 94–103%. With excellent sensitivity and good selectivity, the proposed method could be applied in a wide range of biological fluids, foods, and pharmaceutical analysis.