bluuebunny/crossref_metadata_2025_split huggingface dataset:
In Situ Industrial Bimetallic Catalyst Characterization using Scanning Transmission Electron Microscopy and X‐ray Absorption Spectroscopy at One Atmosphere and Elevated Temperature
Authors: Prestat Eric , Kulzick Matthew A. , Dietrich Paul J. , Smith Mr. Matthew , Tien Mr. Eu‐Pin , Burke M. Grace , Haigh Sarah J. , Zaluzec Nestor J. 
Published: June 2017

AbstractWe have developed a new experimental platform for in situ scanning transmission electron microscope (STEM) energy dispersive X‐ray spectroscopy (EDS) which allows real time, nanoscale, elemental and structural changes to be studied at elevated temperature (up to 1000 °C) and pressure (up to 1 atm). Here we demonstrate the first application of this approach to understand complex structural changes occurring during reduction of a bimetallic catalyst, PdCu supported on TiO2, synthesized by wet impregnation. We reveal a heterogeneous evolution of nanoparticle size, distribution, and composition with large differences in reduction behavior for the two metals. We show that the data obtained is complementary to in situ STEM electron energy loss spectroscopy (EELS) and when combined with in situ X‐ray absorption spectroscopy (XAS) allows correlation of bulk chemical state with nanoscale changes in elemental distribution during reduction, facilitating new understanding of the catalytic behavior for this important class of materials.
Electrospinning Hetero‐Nanofibers of Fe3C‐Mo2C/Nitrogen‐Doped‐Carbon as Efficient Electrocatalysts for Hydrogen Evolution
Authors: Lin Huanlei , Zhang Wenbiao , Shi Zhangping , Che Minwei , Yu Xiang , Tang Yi , Gao Qingsheng 
Published: June 2017

AbstractInvited for this month′s cover is the group of Qingsheng Gao at Jinan University. The image shows the synergistically improved kinetics on Fe3C‐Mo2C hetero‐interfaces for hydrogen evolution, as illustrated by the easily passed hurdles in hurdle race. The Full Paper itself is available at 10.1002/cssc.201700207.
Tropical soils degraded by slash‐and‐burn cultivation can be recultivated when amended with ashes and compost
Authors: Gay‐des‐Combes Justine Marie , Sanz Carrillo Clara , Robroek Bjorn Jozef Maria , Jassey Vincent Eric Jules , Mills Robert Thomas Edmund , Arif Muhammad Saleem , Falquet Leia , Frossard Emmanuel , Buttler Alexandre 
Published: June 2017

AbstractIn many tropical regions, slash‐and‐burn agriculture is considered as a driver of deforestation; the forest is converted into agricultural land by cutting and burning the trees. However, the fields are abandoned after few years because of yield decrease and weed invasion. Consequently, new surfaces are regularly cleared from the primary forest. We propose a reclamation strategy for abandoned fields allowing and sustaining re‐cultivation. In the dry region of south‐western Madagascar, we tested, according to a split‐plot design, an alternative selective slash‐and‐burn cultivation technique coupled with compost amendment on 30–year‐old abandoned fields. Corn plants (Zea mays L.) were grown on four different types of soil amendments: no amendment (control), compost, ashes (as in traditional slash‐and‐burn cultivation), and compost + ashes additions. Furthermore, two tree cover treatments were applied: 0% tree cover (as in traditional slash‐and‐burn cultivation) and 50% tree cover (selective slash‐and‐burn). Both corn growth and soil fertility parameters were monitored during the growing season 2015 up to final harvest. The amendment compost + ashes strongly increased corn yield, which was multiplied by 4–5 in comparison with ashes or compost alone, reaching 1.5 t/ha compared to 0.25 and 0.35 t/ha for ashes and compost, respectively. On control plots, yield was negligible as expected on these degraded soils. Structural equation modeling evidenced that compost and ashes were complementary fertilizing pathways promoting soil fertility through positive effects on soil moisture, pH, organic matter, and microbial activity. Concerning the tree cover treatment, yield was reduced on shaded plots (50% tree cover) compared to sunny plots (0% tree cover) for all soil amendments, except ashes. To conclude, our results provide empirical evidence on the potential of recultivating tropical degraded soils with compost and ashes. This would help mitigating deforestation of the primary forest by increasing lifespan of agricultural lands.
Post‐fire vegetation response at the woodland–shrubland interface is mediated by the pre‐fire community
Authors: Urza Alexandra K. , Weisberg Peter J. , Chambers Jeanne C. , Dhaemers Jessica M. , Board David 
Published: June 2017

AbstractUnderstanding the drivers of ecosystem responses to disturbance is essential for management aimed at maintaining or restoring ecosystem processes and services, especially where invasive species respond strongly to disturbance. In this study, we used repeat vegetation surveys from a network of prescribed fire treatments at the woodland–shrubland interface in the Shoshone Mountains, Nevada, USA, to investigate post‐fire responses of the understory plant community. First, we characterized post‐fire community trajectories for sites located along an elevational gradient, hypothesizing a positive relationship between elevation and resistance to invasion. Unburned understory communities and their responses to disturbance differed along the gradient. As hypothesized, lower elevations experienced greater species turnover and higher invasive annual grass (Bromus tectorum) cover after fire. Second, we characterized post‐fire plant community trajectories for sites with varying levels of pre‐fire pinyon and juniper cover, hypothesizing that pre‐fire tree dominance and associated reductions in perennial understory species lead to less predictable post‐fire trajectories. Among sites with low‐to‐moderate tree cover, burning largely eliminated differences in understory composition, suggesting that biotic legacies were sufficient to result in predictable trajectories. In contrast, sites with high pre‐fire tree cover transitioned into an annual forb‐dominated community with sparse vegetation cover, suggesting that the loss of the understory community initiated unpredictable and divergent post‐fire trajectories. Because plant communities were still changing four years after fire, it is unclear whether the alternate trajectories in sites with high tree cover will result in the formation of alternate states, or whether community composition will eventually converge with other sites at the same elevation. Results indicate that careful evaluation of site characteristics can be used to predict treatment outcomes at the woodland–shrubland interface, and to guide the appropriate use of prescribed fire or other management practices.
Nonstationary POT modelling of air pollution concentrations: Statistical analysis of the traffic and meteorological impact
Authors: Gyarmati‐Szabó János , Bogachev Leonid V. , Chen Haibo 
Published: June 2017

Predicting the occurrence, level, and duration of high air pollution concentrations exceeding a given critical level enables researchers to study the health impact of road traffic on local air quality and to inform public policy action. Precise estimates of the probabilities of occurrence and level of extreme concentrations are formidable due to the combination of complex physical and chemical processes involved. This underpins the need for developing sophisticated extreme value models, in particular allowing for nonstationarity of environmental time series. In this paper, extremes of nitrogen oxide (NO), nitrogen dioxide (NO2), and ozone (O3) concentrations are investigated using two models. Model I is based on an extended peaks‐over‐threshold (POT) approach developed by A. C. Davison and R. L. Smith, whereby the parameters of the underlying generalized Pareto distribution (GPD) are treated as functions of covariates (i.e., traffic and meteorological factors). The new Model II resolves the lack of threshold stability in the Davison–Smith model by constructing a special functional form for the GPD parameters. For each of the models, the effects of traffic and meteorological factors on the frequency and size of extreme values are estimated using Markov chain Monte Carlo methods. Finally, appropriate goodness‐of‐fit tests and model selection criteria confirm that Model II significantly outperforms Model I in estimation and forecasting of extremes.
Integrative gene set enrichment analysis utilizing isoform‐specific expression
Authors: Li Lie , Wang Xinlei , Xiao Guanghua , Gazdar Adi 
Published: June 2017

ABSTRACTGene set enrichment analysis (GSEA) aims at identifying essential pathways, or more generally, sets of biologically related genes that are involved in complex human diseases. In the past, many studies have shown that GSEA is a very useful bioinformatics tool that plays critical roles in the innovation of disease prevention and intervention strategies. Despite its tremendous success, it is striking that conclusions of GSEA drawn from isolated studies are often sparse, and different studies may lead to inconsistent and sometimes contradictory results. Further, in the wake of next generation sequencing technologies, it has been made possible to measure genome‐wide isoform‐specific expression levels, calling for innovations that can utilize the unprecedented resolution. Currently, enormous amounts of data have been created from various RNA‐seq experiments. All these give rise to a pressing need for developing integrative methods that allow for explicit utilization of isoform‐specific expression, to combine multiple enrichment studies, in order to enhance the power, reproducibility, and interpretability of the analysis. We develop and evaluate integrative GSEA methods, based on two‐stage procedures, which, for the first time, allow statistically efficient use of isoform‐specific expression from multiple RNA‐seq experiments. Through simulation and real data analysis, we show that our methods can greatly improve the performance in identifying essential gene sets compared to existing methods that can only use gene‐level expression.
AHNS Series – Do you know your guidelines? Lip cancer
Authors: Dougherty William , Givi Babak , Jameson Mark J. ,   Education Committee of the American Head and Neck Society
Published: June 2017

AbstractBackgroundLip cancer is one of the most curable primary head and neck malignancies, as the prominent location typically lends to an early diagnosis. The incidence of lip cancer varies by sex, ethnicity, and region, but is estimated to be up to 2.5/100 000 in the United States (squamous cell carcinoma [SCC]).MethodsThis article will review the current literature and National Comprehensive Cancer Network practice guidelines in the treatment of lip cancer.ResultsResection of lip cancer with negative margins remains the mainstay of therapy. Positive nodal disease should be treated with neck dissection and adjuvant radiotherapy.ConclusionLip cancer remains highly curable when diagnosed at an early stage. A multidisciplinary approach is crucial to treating patients with advanced‐stage lip cancer.
High purity fructose from inulin with heterogeneous catalysis – kinetics and modelling
Authors: Pérez Nebreda Andrea , Salmi Tapio , Murzin Dmitry Yu , Grénman Henrik 
Published: June 2017

AbstractBACKGROUNDInulin can be extracted from the non‐edible chicory root and high purity fructose can be obtained from hydrolysis of inulin and used as a valuable platform molecule for further valorization. Heterogeneous catalysts are sought as alternatives to mineral acids because of costly separation and severe corrosion problems. In this work, hydrolysis of inulin was performed in a batch reactor with an advanced sulfonic resin (Smopex‐101) employing HCl as a reference catalyst, at 75–95 °C and pH ranging from 1 to 2.RESULTSThe reaction was shown to proceed predominantly via an end‐biting mechanism. The activity of the heterogeneous catalyst was on par with the reference catalyst, with the special advantage that Smopex‐101 was more selective towards monomer formation at milder reaction conditions. Mathematical modelling of the kinetics was successfully performed with a recently developed model incorporating a reaction mechanism based on an autocatalytic effect.CONCLUSIONSThe current work demonstrates that high purity fructose can be obtained by hydrolysis of inulin employing a heterogeneous catalyst at ambient pressure. The results can be utilized directly for optimization and design purposes and they open up novel possibilities in production and process design, i.e. batch or possibly continuous operation without the need for costly separation and corrosion problems commonly encountered with homogeneous catalysts. © 2017 Society of Chemical Industry
Connexins and pannexins: At the junction of neuro‐glial homeostasis & disease
Authors: Lapato Andrew S. , Tiwari‐Woodruff Seema K. 
Published: June 2017

AbstractIn the central nervous system (CNS), connexin (Cx)s and pannexin (Panx)s are an integral component of homeostatic neuronal excitability and synaptic plasticity. Neuronal Cx gap junctions form electrical synapses across biochemically similar GABAergic networks, allowing rapid and extensive inhibition in response to principle neuron excitation. Glial Cx gap junctions link astrocytes and oligodendrocytes in the pan‐glial network that is responsible for removing excitotoxic ions and metabolites. In addition, glial gap junctions help constrain excessive excitatory activity in neurons and facilitate astrocyte Ca2+ slow wave propagation. Panxs do not form gap junctions in vivo, but Panx hemichannels participate in autocrine and paracrine gliotransmission, alongside Cx hemichannels. ATP and other gliotransmitters released by Cx and Panx hemichannels maintain physiologic glutamatergic tone by strengthening synapses and mitigating aberrant high frequency bursting. Under pathological depolarizing and inflammatory conditions, gap junctions and hemichannels become dysregulated, resulting in excessive neuronal firing and seizure. In this review, we present known contributions of Cxs and Panxs to physiologic neuronal excitation and explore how the disruption of gap junctions and hemichannels lead to abnormal glutamatergic transmission, purinergic signaling, and seizures.
Comparison of partial least squares and random forests for evaluating relationship between phenolics and bioactivities of Neptunia oleracea
Authors: Lee Soo Yee , Mediani Ahmed , Maulidiani Maulidiani , Khatib Alfi , Ismail Intan Safinar , Zawawi Norhasnida , Abas Faridah 
Published: June 2017

AbstractBACKGROUNDNeptunia oleracea is a plant consumed as a vegetable and which has been used as a folk remedy for several diseases. Herein, two regression models (partial least squares, PLS; and random forest, RF) in a metabolomics approach were compared and applied to the evaluation of the relationship between phenolics and bioactivities of N. oleracea. In addition, the effects of different extraction conditions on the phenolic constituents were assessed by pattern recognition analysis.RESULTSComparison of the PLS and RF showed that RF exhibited poorer generalization and hence poorer predictive performance. Both the regression coefficient of PLS and the variable importance of RF revealed that quercetin and kaempferol derivatives, caffeic acid and vitexin‐2‐O‐rhamnoside were significant towards the tested bioactivities. Furthermore, principal component analysis (PCA) and partial least squares–discriminant analysis (PLS‐DA) results showed that sonication and absolute ethanol are the preferable extraction method and ethanol ratio, respectively, to produce N. oleracea extracts with high phenolic levels and therefore high DPPH scavenging and α‐glucosidase inhibitory activities.CONCLUSIONBoth PLS and RF are useful regression models in metabolomics studies. This work provides insight into the performance of different multivariate data analysis tools and the effects of different extraction conditions on the extraction of desired phenolics from plants. © 2017 Society of Chemical Industry
Synthesis of Photocrosslinkable and Amine Containing Multifunctional Nanoparticles via Polymerization‐Induced Self‐Assembly
Authors: Huang Jianbing , Li Decai , Liang Hui , Lu Jiang 
Published: June 2017

Photo‐crosslinkable and amine‐containing block copolymer nanoparticles are synthesized via reversible addition–fragmentation chain transfer (RAFT) polymerization‐induced self‐assembly of a multifunctional core‐forming monomer, 2‐((3‐(4‐(diethylamino)phenyl)acryloyl)oxy)ethyl methacrylate (DEMA), using poly(2‐hydroxypropyl methacrylate) macromolecular chain transfer agent as a steric stabilizer in methanol at 65 °C. By tuning the chain length of PDEMA, a range of nanoparticle morphologies (sphere, worm, and vesicle) can be obtained. Since cinnamate groups can easily undergo a [2 + 2] cycloaddition of the carbon–carbon double bonds upon UV irradiation, the as‐prepared block copolymer nanoparticles are readily stabilized by photo‐crosslinking to produce anisotropic nanoparticles. The crosslinked block copolymer nanoparticles can be used as templates for in situ formation polymer/gold hybrid nanoparticles.
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Fabrication of pH‐ and Thermoresponsive Three‐Layered Micelles via Host–Guest Interactions
Authors: Zhang Jingyan , Zhou Haiou , Liu Hao , Hu Jinming , Liu Shiyong 
Published: June 2017

AbstractWell‐defined β‐cyclodextrin (β‐CD)‐terminated double hydrophilic diblock copolymers (DHBCs), β‐CD‐ poly(di(ethylene glycol) methyl ether methacrylate) (PMEO2MA)‐b‐poly(2‐(diethylamino)ethyl methacrylate) (PDEA) (BP1) and β‐CD‐PDEA‐b‐PMEO2MA (BP2), are synthesized via sequential atom transfer radical polymerizations of di(ethylene glycol) methyl ether methacrylate and 2‐(diethylamino)ethyl methacrylate using alkynyl‐functionalized initiator, followed by click reactions with an excess of mono‐azido‐substituted β‐cyclodextrin (β‐CD‐N3). The micellization behavior of these as‐prepared DHBCs in aqueous solutions suffers from insufficient colloidal stabilities at basic pH and high temperatures (e.g., pH 9 and 45 °C), resulting in the formation of macroscopic precipitations. However, the stabilities of colloidal nanoparticles can be remarkably enhanced as a result of the convenient formation of three‐layered micelles by taking advantage of host–guest interactions of BP1/BP2 and Ad‐terminated poly(ethylene glycol). The pH‐ and thermoresponsive three‐layered micelles with enhanced stability may augur promising applications in targeted drug delivery and controlled intelligent release.
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A random walk‐based segmentation framework for 3D ultrasound images of the prostate
Authors: Ma Ling , Guo Rongrong , Tian Zhiqiang , Fei Baowei 
Published: June 2017

PurposeAccurate segmentation of the prostate on ultrasound images has many applications in prostate cancer diagnosis and therapy. Transrectal ultrasound (TRUS) has been routinely used to guide prostate biopsy. This manuscript proposes a semiautomatic segmentation method for the prostate on three‐dimensional (3D) TRUS images.MethodsThe proposed segmentation method uses a context‐classification‐based random walk algorithm. Because context information reflects patient‐specific characteristics and prostate changes in the adjacent slices, and classification information reflects population‐based prior knowledge, we combine the context and classification information at the same time in order to define the applicable population and patient‐specific knowledge so as to more accurately determine the seed points for the random walk algorithm. The method is initialized with the user drawing the prostate and non‐prostate circles on the mid‐gland slice and then automatically segments the prostate on other slices. To achieve reliable classification, we use a new adaptive k‐means algorithm to cluster the training data and train multiple decision‐tree classifiers. According to the patient‐specific characteristics, the most suitable classifier is selected and combined with the context information in order to locate the seed points. By providing accuracy locations of the seed points, the random walk algorithm improves segmentation performance.ResultsWe evaluate the proposed segmentation approach on a set of 3D TRUS volumes of prostate patients. The experimental results show that our method achieved a Dice similarity coefficient of 91.0% ± 1.6% as compared to manual segmentation by clinically experienced radiologist.ConclusionsThe random walk‐based segmentation framework, which combines patient‐specific characteristics and population information, is effective for segmenting the prostate on ultrasound images. The segmentation method can have various applications in ultrasound‐guided prostate procedures.
Model‐based T1 mapping with sparsity constraints using single‐shot inversion‐recovery radial FLASH
Authors: Wang Xiaoqing , Roeloffs Volkert , Klosowski Jakob , Tan Zhengguo , Voit Dirk , Uecker Martin , Frahm Jens 
Published: June 2017

PurposeTo develop a model‐based reconstruction technique for single‐shot T1 mapping with high spatial resolution, accuracy, and precision using an inversion‐recovery (IR) fast low‐angle shot (FLASH) acquisition with radial encoding.MethodsThe proposed model‐based reconstruction jointly estimates all model parameters, that is, the equilibrium magnetization, steady‐state magnetization, 1/
, and all coil sensitivities from the data of a single‐shot IR FLASH acquisition with a small golden‐angle radial trajectory. Joint sparsity constraints on the parameter maps are exploited to improve the performance of the iteratively regularized Gauss‐Newton method chosen for solving the nonlinear inverse problem. Validations include both a numerical and experimental T1 phantom, as well as in vivo studies of the human brain and liver at 3 T.ResultsIn comparison to previous reconstruction methods for single‐shot T1 mapping, which are based on real‐time MRI with pixel‐wise fitting and a model‐based approach with a predetermination of coil sensitivities, the proposed method presents with improved robustness against phase errors and numerical precision in both phantom and in vivo studies.ConclusionThe comprehensive model‐based reconstruction with L1 regularization offers rapid and robust T1 mapping with high accuracy and precision. The method warrants accelerated computing and online implementation for extended clinical trials. Magn Reson Med 79:730–740, 2018. © 2017 International Society for Magnetic Resonance in Medicine.
Decoupling of a tight‐fit transceiver phased array for human brain imaging at 9.4T: Loop overlapping rediscovered
Authors: Avdievich Nikolai I. , Giapitzakis Ioannis‐Angelos , Pfrommer Andreas , Henning Anke 
Published: June 2017

PurposeTo improve the decoupling of a transceiver human head phased array at ultra‐high fields (UHF, ≥ 7T) and to optimize its transmit (Tx) and receive (Rx) performance, a single‐row eight‐element (1 × 8) tight‐fit transceiver overlapped loop array was developed and constructed. Overlapping the loops increases the RF field penetration depth but can compromise decoupling by generating substantial mutual resistance.MethodsBased on analytical modeling, we optimized the loop geometry and relative positioning to simultaneously minimize the resistive and inductive coupling and constructed a 9.4T eight‐loop transceiver head phased array decoupled entirely by overlapping loops.ResultsWe demonstrated that both the magnetic and electric coupling between adjacent loops is compensated at the same time by overlapping and nearly perfect decoupling (below ‐30 dB) can be obtained without additional decoupling strategies. Tx‐efficiency and SNR of the overlapped array outperformed that of a common UHF gapped array of similar dimensions. Parallel Rx‐performance was also not compromised due to overlapping the loops.ConclusionAs a proof of concept we developed and constructed a 9.4T (400 MHz) overlapped transceiver head array based on results of the analytical modeling. We demonstrated that at UHF overlapping loops not only provides excellent decoupling but also improves both Tx‐ and Rx‐performance. Magn Reson Med 79:1200–1211, 2018. © 2017 International Society for Magnetic Resonance in Medicine.