bluuebunny/crossref_metadata_2025_split huggingface dataset:
DEM investigations of internal erosion: Grain transport in the light of micromechanics
Authors: Wautier Antoine , Bonelli Stéphane , Nicot François 
Published: October 2018

SummaryInternal erosion by suffusion can change dramatically the constitutive behavior of granular materials by modifying the fabric of granular materials. In this study, the effect of an internal fluid flow on granular materials is investigated at the material point scale using the numerical coupling between a discrete element method (DEM) and a pore‐scale finite volume (PFV) coupling scheme. The influence of the stress state and the hydraulic loading (direction and intensity) on the occurrence of grain transport in dense widely graded granular samples is thus investigated and interpreted in terms of micromechanics. In particular, it is shown that grain transport is increased when the macroscopic flow direction is aligned with the privileged force chain orientation. The stress‐induced microstructure modifications are shown to influence the transport distances by controlling the number of rattlers.
Probabilistic learning for modeling and quantifying model‐form uncertainties in nonlinear computational mechanics
Authors: Soize C. , Farhat C. 
Published: October 2018

SummaryRecently, a novel nonparametric probabilistic method for modeling and quantifying model‐form uncertainties in nonlinear computational mechanics was proposed. Its potential was demonstrated through several uncertainty quantification (UQ) applications in vibration analysis and nonlinear computational structural dynamics. This method, which relies on projection‐based model order reduction to achieve computational feasibility, exhibits a vector‐valued hyperparameter in the probability model of the random reduced‐order basis and associated stochastic projection‐based reduced‐order model. It identifies this hyperparameter by formulating a statistical inverse problem, grounded in target quantities of interest, and solving the corresponding nonconvex optimization problem. For many practical applications, however, this identification approach is computationally intensive. For this reason, this paper presents a faster predictor‐corrector approach for determining the appropriate value of the vector‐valued hyperparameter that is based on a probabilistic learning on manifolds. It also demonstrates the computational advantages of this alternative identification approach through the UQ of two three‐dimensional nonlinear structural dynamics problems associated with two different configurations of a microelectromechanical systems device.
Hydrogeophysical characterization of shallow light non‐aqueous phase liquid contamination at a karst aquifer
Authors: Rajab Jafar Abu , El‐Naqa Ali , Al‐Qinna Mohammed 
Published: October 2018

ABSTRACTTwo wells at an industrial facility were recently removed from service due to signs of long‐term hydrocarbon contamination. Groundwater monitoring at the polluted wells documented the presence of a massive body of light non‐aqueous phase liquid materials that were accumulated at a depth of ∼50 m in the water table. We have used transient electromagnetic and electrical resistivity tomography to characterize the ground at the light non‐aqueous phase liquid contaminated wells. Additionally, analyses of hydrochemical samples and calculations of hydrogeological parameters have been implemented to interpret and describe the geophysical signatures of several anomalous hydrocarbon contaminations.Resistivity models, which are based on the three‐dimensional inversion of transient electromagnetic data and the two‐dimensional inversion of electrical resistivity tomography lines conducted at the source of leaks and contaminated wells, confirmed the presence of a hyper‐conductive zone (i.e. 0.5 Ω⋅m), 15 m deep and 20 m thick, that contained a mixture of light non‐aqueous phase liquid, hot water, and chemical acids. In addition, resistivity levels up to hundreds of ohm metre can be attributed to near‐surface cavernous structures. Furthermore, the resistivity models can resolve a 30‐m‐thick conductive layer underlying cavernous structures, yielding resistivity values ranging from 0.78 to 5 Ω⋅m. The ease of light non‐aqueous phase liquid migration is promoted due to zones of cavernous structures acting as preferential flow pathways down to the water table, where light non‐aqueous phase liquid materials follow the hydraulic gradient of the limestone aquifer, which has a calculated porosity of 20%. Chemical analysis of groundwater samples at contaminated well sites shows the depletion of sulphate and nitrate concentrations and an increase in bicarbonate at locations where the highest hydraulic conductivities are observed. These findings facilitates the construction of a conceptual model for contamination which is used to better understand the evolution of light non‐aqueous phase liquid pollution at the study area.
The elixir phase of chain molecules
Authors: Škrbić Tatjana , Hoang Trinh X. , Maritan Amos , Banavar Jayanth R. , Giacometti Achille 
Published: October 2018

AbstractA phase of matter is a familiar notion for inanimate physical matter. The nature of a phase of matter transcends the microscopic material properties. For example, materials in the liquid phase have certain common properties independent of the chemistry of the constituents: liquids take the shape of the container; they flow; and they can be poured—alcohol, oil, and water as well as a Lennard‐Jones computer model exhibit similar behavior when poised in the liquid phase. Here, we identify a hitherto unstudied “phase” of matter, the elixir phase, in a simple model of a polymeric chain whose backbone has the correct local cylindrical symmetry induced by the tangent to the chain. The elixir phase appears on breaking the cylindrical symmetry by adding side spheres along the negative normal direction, as in proteins. This phase, nestled between other phases, has multiple ground states made up of building blocks of helices and almost planar sheets akin to protein native folds. We discuss the similarities of this “phase” of a finite size system to the liquid crystal and spin glass phases. Our findings are relevant for understanding proteins; the creation of novel bioinspired nanomachines; and also may have implications for life elsewhere in the cosmos.
Preparation of cyflumetofen nanocapsules and study on the controlled release performance and its field efficacy
Authors: Peng Xinya , Hu Yue , Wang Yalan , Xue Fei , Shen Guangmao , Dong Yike , He Lin , Qian Kun 
Published: October 2018

AbstractBACKGROUNDIn this study, 5% cyflumetofen nanocapsules were prepared by interfacial polymerization with isophorone diisocyanate and polyethylene glycol as the reaction monomer, and tristyrylphenol polyoxyethylene ether (601‐P) as the emulsifier. The physical, chemical and sustained release properties of cyflumetofen nanocapsules were characterized using scanning electron microscopy, field emission scanning electron microscopy, laser particle size analysis, Fourier transform infrared spectroscopy, contact angles testing and high‐performance liquid chromatography.RESULTSThe results indicated that cyflumetofen nanocapsules were spherical, with an average particle size of 100 nm, and an encapsulation efficiency and loading rate of 86% and 32%, respectively. The thermal and cold storage stabilities of cyflumetofen nanocapsules were good. Under high temperature, lower pH or a high core–wall ratio, nanoparticle release is faster. The field efficacy experiment indicated that the efficacy of cyflumetofen nanocapsules against Panonychus citri reached 97%, 30 days after spraying, significantly greater than that of a 20% cyflumetofen suspension.CONCLUSIONIt is important to increase the stability, lengthen the release period and improve the efficacy of cyflumetofen in cyflumetofen nanocapsules. © 2018 Society of Chemical Industry
Controlling type 1 error rate for sequential, bioequivalence studies with crossover designs
Authors: Rasmussen Hans E. , Ma Rick , Wang Jessie J. 
Published: October 2018

SummarySample size reestimation in a crossover, bioequivalence study can be a useful adaptive design tool, particularly when the intrasubject variability of the drug formulation under investigation is not well understood. When sample size reestimation is done based on an interim estimate of the intrasubject variability and bioequivalence is tested using the pooled estimate of intrasubject variability, type 1 error inflation will occur. Type 1 error inflation is caused by the pooled estimate being a biased estimator of the intrasubject variability. The type 1 error inflation and bias of the pooled estimator of variability are well characterized in the setting of a two‐arm, parallel study. The purpose of this work is to extend this characterization to the setting of a crossover, bioequivalence study with sample size reestimation and to propose an estimator of the intrasubject variability that will prevent type 1 error inflation.
Contagious sets in a degree‐proportional bootstrap percolation process
Authors: Garbe Frederik , Mycroft Richard , McDowell Andrew 
Published: October 2018

We study the following bootstrap percolation process: given a connected graph G, a constant ρ ∈ [0,1] and an initial set A⊆V(G) of infected vertices, at each step a vertex v becomes infected if at least a ρ‐proportion of its neighbors are already infected (once infected, a vertex remains infected forever). Our focus is on the size hρ(G) of a smallest initial set which is contagious, meaning that this process results in the infection of every vertex of G. Our main result states that every connected graph G on n vertices has hρ(G) < 2ρn or hρ(G) = 1 (note that allowing the latter possibility is necessary because of the case , as every contagious set has size at least one). This is the best‐possible bound of this form, and improves on previous results of Chang and Lyuu and of Gentner and Rautenbach. We also provide a stronger bound for graphs of girth at least five and sufficiently small ρ, which is asymptotically best‐possible.
Some principles are more equal than others: Promotion‐ versus prevention‐focused effectuation principles and their disparate relationships with entrepreneurial orientation
Authors: Palmié Maximilian , Huerzeler Peter , Grichnik Dietmar , Keupp Marcus M. , Gassmann Oliver 
Published: October 2018

Research SummaryRecent research suggests that effectuation principles such as flexibility, precommitments, and affordable loss may differ substantially from one another. Responding to the call to clarify the effectuation concept, our study introduces the distinction between promotion‐ and prevention‐focused effectuation principles. It argues that promotion‐focused (prevention‐focused) principles are positively (negatively) associated with a firm's entrepreneurial orientation (EO). It further argues that causation is also promotion‐focused and positively associated with EO. An analysis of 151 Swiss energy small and medium‐sized enterprises supports this account. Thus, our study suggests that some effectuation principles are more similar to causation in their underlying regulatory focus and their relationship with EO than they are to other effectuation principles. We offer several paths for future research on effectuation, causation, and EO that emerge from these findings.Managerial SummaryPractitioner‐oriented presentations and texts on entrepreneurial decision making frequently portray the means‐driven effectuation approach as opposite to the goals‐driven causation approach. Our study challenges this portrayal by highlighting substantial differences between the individual effectuation principles. Specifically, our research suggests that these principles differ in the underlying psychological processes and consequently in their relationships with key organizational attributes such as the firm's entrepreneurial orientation. In these important regards, some effectuation principles are actually more similar to causation than they are to other effectuation principles. Our study has substantial implications for the adoption of effectuation and for the “mixing and matching” of effectuation and causation. It not only makes a difference whether decision makers pursue an effectuation or causation approach, but also which effectuation principles they choose.
Two‐Dimensional Layered Hydroxide Nanoporous Nanohybrids Pillared with Zero‐Dimensional Polyoxovanadate Nanoclusters for Enhanced Water Oxidation Catalysis
Authors: Gunjakar Jayavant L. , Hou Bo , Inamdar Akbar I. , Pawar Sambhaji M. , Ahmed Abu Talha Aqueel , Chavan Harish S. , Kim Jongmin , Cho Sangeun , Lee Seongwoo , Jo Yongcheol , Hwang Seong‐Ju , Kim Tae Geun , Cha SeungNam , Kim Hyungsang , Im Hyunsik 
Published: October 2018

AbstractThe oxygen‐evolution reaction (OER) is critical in electrochemical water splitting and requires an efficient, sustainable, and cheap catalyst for successful practical applications. A common development strategy for OER catalysts is to search for facile routes for the synthesis of new catalytic materials with optimized chemical compositions and structures. Here, nickel hydroxide Ni(OH)2 2D nanosheets pillared with 0D polyoxovanadate (POV) nanoclusters as an OER catalyst that can operate in alkaline media are reported. The intercalation of POV nanoclusters into Ni(OH)2 induces the formation of a nanoporous layer‐by‐layer stacking architecture of 2D Ni(OH)2 nanosheets and 0D POV with a tunable chemical composition. The nanohybrid catalysts remarkably enhance the OER activity of pristine Ni(OH)2. The present findings demonstrate that the intercalation of 0D POV nanoclusters into Ni(OH)2 is effective for improving water oxidation catalysis and represents a potential method to synthesize novel, porous hydroxide‐based nanohybrid materials with superior electrochemical activities.
RNA‐Based Immunostimulatory Liposomal Spherical Nucleic Acids as Potent TLR7/8 Modulators
Authors: Guan Chenxia , Chernyak Natalia , Dominguez Donye , Cole Lisa , Zhang Bin , Mirkin Chad A. 
Published: October 2018

AbstractImmunostimulatory spherical nucleic acids (IS‐LSNAs) comprised of RNA selective for toll‐like receptors (TLRs) 7/8 are synthesized and characterized. These structures consist of liposomal cores functionalized with a dense shell of RNA inserted into the wall of the lipid core via hydrophobic cholesterol moieties. IS‐LSNAs potently activate TLR7/8 via NF‐κΒ signaling in reporter cell lines and in primary immune cells as evidenced by cytokine production and the upregulation of costimulatory receptors. Importantly, they are preferentially taken up by plasmacytoid dendritic cells, an observation that makes them potentially useful for immunotherapy. In addition, these structures contain a core that can be loaded with antigens and used to prime T cells. In this regard, it is shown that dendritic cells treated with IS‐SNAs loaded with ovalbumin peptide can prime ova specific CD8+ T cells. In addition to introducing the first IS‐LSNAs consisting of RNA, these experiments show that one can facilitate an antigen‐specific T cell response greater than that of free or cationic lipid‐transfected RNA of the same sequence selective for TLR7/8. This work points toward the promise of using IS‐LSNAs comprised of RNA as potent and highly tunable TLR‐specific agents for the development of vaccines and other pharmaceuticals that require selective immunomodulation.
Tumor Starvation Induced Spatiotemporal Control over Chemotherapy for Synergistic Therapy
Authors: Zhang Ming‐Kang , Li Chu‐Xin , Wang Shi‐Bo , Liu Tao , Song Xian‐Lin , Yang Xiao‐Quan , Feng Jun , Zhang Xian‐Zheng 
Published: October 2018

AbstractBy integrating the characteristics of each therapy modality and material chemistry, a multitherapy modality is put forward: tumor starvation triggered synergism with sensitized chemotherapy. Following starvation‐induced amplification of pathological abnormalities in tumors, chemotherapy is arranged to be locally activated and accurately reinforced to perfect multitherapy synergism from spatial and temporal perspectives. To this end, glucose oxidase (GOD) and a hypoxic prodrug of tirapazamine (TPZ) are loaded in acidity‐decomposable calcium carbonate (CaCO3) nanoparticles concurrently tethered by hyaluronic acid. This hybrid nanotherapeutic shows a strong tendency to accumulate in tumors postinjection due to the cooperation between passive and active targeting mechanisms. The GOD‐driven oxidation reaction deprives tumors of glucose for starvation therapy and concomitantly induces tumorous abnormality amplifications including elevated acidity and exacerbated hypoxia. Programmatically, the acidity amplification causes CaCO3 decomposition, offering not only spatial control over the liberation of embedded TPZ just within tumors but also the temporal control over timely chemotherapy initiation to match the occurrence of hypoxia amplification and thus benefiting perfect synergism between starvation therapy and chemotherapy.
Gaining insight into transcriptome‐wide RNA population dynamics through the chemistry of 4‐thiouridine
Authors: Duffy Erin E. , Schofield Jeremy A. , Simon Matthew D. 
Published: October 2018

Cellular RNA levels are the result of a juggling act between RNA transcription, processing, and degradation. By tuning one or more of these parameters, cells can rapidly alter the available pool of transcripts in response to stimuli. While RNA sequencing (RNA‐seq) is a vital method to quantify RNA levels genome‐wide, it is unable to capture the dynamics of different RNA populations at steady‐state or distinguish between different mechanisms that induce changes to the steady‐state (i.e., altered rate of transcription vs. degradation). The dynamics of different RNA populations can be studied by targeted incorporation of noncanonical nucleosides. 4‐Thiouridine (s4U) is a commonly used and versatile RNA metabolic label that allows the study of many properties of RNA metabolism from synthesis to degradation. Numerous experimental strategies have been developed that leverage the power of s4U to label newly transcribed RNA in whole cells, followed by enrichment with activated disulfides or chemistry to induce C mutations at sites of s4U during sequencing. This review presents existing methods to study RNA population dynamics genome‐wide using s4U metabolic labeling, as well as a discussion of considerations and challenges when designing s4U metabolic labeling experiments.This article is categorized under:

RNA Methods > RNA Analyses in Cells
RNA Turnover and Surveillance > Regulation of RNA Stability
The Play of Breath: Chaucer’s Narratives of Feeling
Authors: Saunders Corinne 
Published: October 2018

AbstractThis essay explores the treatment of breath and breathlessness in the imaginative fiction of Geoffrey Chaucer. Chaucer draws on medieval medical theories, rooted in classical thought, to portray the ways that motions of the vital spirit—closely connected with breath—create powerful physical responses, which at their most extreme cause sighs and swoons. According to this pre-Cartesian world view, mind, body and affect are intimately connected. The movement of breath plays a key role in Chaucer’s depiction of the experiences of emotion, particularly love and grief, and in his treatment of gender. This physiological emphasis creates narratives of feeling that are deeply embodied. The essay focuses on Chaucer’s romance writing, in particular,The Book of the Duchess,Troilus and CriseydeandThe Legend of Good Women.
Experimental design and model reduction in systems biology
Authors: Jeong Jenny E. , Zhuang Qinwei , Transtrum Mark K. , Zhou Enlu , Qiu Peng 
Published: October 2018

BackgroundIn systems biology, the dynamics of biological networks are often modeled with ordinary differential equations (ODEs) that encode interacting components in the systems, resulting in highly complex models. In contrast, the amount of experimentally available data is almost always limited, and insufficient to constrain the parameters. In this situation, parameter estimation is a very challenging problem. To address this challenge, two intuitive approaches are to perform experimental design to generate more data, and to perform model reduction to simplify the model. Experimental design and model reduction have been traditionally viewed as two distinct areas, and an extensive literature and excellent reviews exist on each of the two areas. Intriguingly, however, the intrinsic connections between the two areas have not been recognized.ResultsExperimental design and model reduction are deeply related, and can be considered as one unified framework. There are two recent methods that can tackle both areas, one based on model manifold and the other based on profile likelihood. We use a simple sum‐of‐two‐exponentials example to discuss the concepts and algorithmic details of both methods, and provide Matlab‐based code and implementation which are useful resources for the dissemination and adoption of experimental design and model reduction in the biology community.ConclusionsFrom a geometric perspective, we consider the experimental data as a point in a high‐dimensional data space and the mathematical model as a manifold living in this space. Parameter estimation can be viewed as a projection of the data point onto the manifold. By examining the singularity around the projected point on the manifold, we can perform both experimental design and model reduction. Experimental design identifies new experiments that expand the manifold and remove the singularity, whereas model reduction identifies the nearest boundary, which is the nearest singularity that suggests an appropriate form of a reduced model. This geometric interpretation represents one step toward the convergence of experimental design and model reduction as a unified framework.
Neuronal variability of Resting State activity in Eating Disorders: increase and decoupling in Ventral Attention Network and relation with clinical symptoms
Authors: Spalatro Angela V. , Amianto Federico , Huang Zirui , D’Agata Federico , Bergui Mauro , Abbate Daga Giovanni , Fassino Secondo , Northoff Georg 
Published: October 2018

AbstractBackground:Despite the great number of resting state functional connectivity studies on Eating Disorders (ED), no biomarkers could be detected yet. Therefore, we here focus on a different measure of resting state activity that is neuronal variability. The objective of this study was to investigate neuronal variability in the resting state of women with ED and to correlate possible differences with clinical and psychopathological indices.Methods:58 women respectively 25 with Anorexia Nervosa (AN), 16 with Bulimia Nervosa (BN) and 17 matched healthy controls (CN) were enrolled for the study. All participants were tested with a battery of psychometric tests and underwent a functional Magnetic Resonance Imaging (fMRI) resting state scanning. We investigated topographical patterns of variability measured by the Standard Deviation (SD) of the Blood-Oxygen-Level-Dependent (BOLD) signal (as a measure of neuronal variability) in the resting-state and their relationship to clinical and psychopathological indices.Results:Neuronal variability was increased in both anorectic and bulimic subjects specifically in the Ventral Attention Network (VAN) compared to healthy controls. No significant differences were found in the other networks. Significant correlations were found between neuronal variability of VAN and various clinical and psychopathological indices.Conclusions:We here show increased neuronal variability of VAN in ED patients. As the VAN is relevant for switching between endogenous and exogenous stimuli, our results showing increased neuronal variability suggest unstable balance between body attention and attention to external world. These results offer new perspective on the neurobiological basis of ED. Clinical and therapeutic implication will be discussed.