bluuebunny/crossref_metadata_2025_split huggingface dataset:
Study of Wave‐Particle Interactions for Whistler Mode Waves at Oblique Angles by Utilizing the Gyroaveraging Method
Authors: Hsieh Yi‐Kai , Omura Yoshiharu 
Published: September 2017

AbstractWe investigate the properties of whistler mode wave‐particle interactions at oblique wave normal angles to the background magnetic field. We find that electromagnetic energy of waves at frequencies below half the electron cyclotron frequency can flow nearly parallel to the ambient magnetic field. We thereby confirm that the gyroaveraging method, which averages the cyclotron motion to the gyrocenter and reduces the simulation from two‐dimensional to one‐dimensional, is valid for oblique wave‐particle interaction. Multiple resonances appear for oblique propagation but not for parallel propagation. We calculate the possible range of resonances with the first‐order resonance condition as a function of electron kinetic energy and equatorial pitch angle. To reveal the physical process and the efficiency of electron acceleration by multiple resonances, we assume a simple uniform wave model with constant amplitude and frequency in space and time. We perform test particle simulations with electrons starting at specific equatorial pitch angles and kinetic energies. The simulation results show that multiple resonances contribute to acceleration and pitch angle scattering of energetic electrons. Especially, we find that electrons with energies of a few hundred keV can be accelerated efficiently to a few MeV through the n = 0 Landau resonance.
Dipole Approximation to Predict the Resonances of Dimers Composed of Dielectric Resonators for Directional Emission
Authors: Campione Salvatore , Warne Larry K. , Basilio Lorena I. 
Published: September 2017

AbstractIn this paper we develop a fully retarded, dipole approximation model to estimate the effective polarizabilities of a dimer made of dielectric resonators. They are computed from the polarizabilities of the two resonators composing the dimer. We analyze the situation of full cubes as well as split cubes, which have been shown to exhibit overlapping electric and magnetic resonances. We compare the effective dimer polarizabilities to ones retrieved via full‐wave simulations as well as ones computed via a quasi‐static, dipole approximation. We observe good agreement between the fully retarded solution and the full‐wave results, whereas the quasi‐static approximation is less accurate for the problem at hand. The developed model can be used to predict the electric and magnetic resonances of a dimer under parallel or orthogonal (to the dimer axis) excitation. This is particularly helpful when interested in locating frequencies at which the dimer will emit directional radiation.
Assessment of GPS Multifrequency Signal Characteristics During Periods of Ionospheric Scintillations from an Anomaly Crest Location
Authors: Goswami S. , Paul K. S. , Paul A. 
Published: September 2017

AbstractMultifrequency GPS transmissions have provided the opportunity for testing the applicability of the principle of frequency diversity for scintillation mitigation. Published results addressing this issue with quantified estimates are not available in literature, at least from the anomaly crest location of the Indian longitude sector. Multifrequency scattering within the same L band is often the attributed cause behind simultaneous decorrelated signal fluctuations. The present paper aims to provide proportion of time during scintillation patches that decorrelations are found across GPS L1, L2, and L5 frequencies associated with high S4, corresponding high values of scattering coefficients, and large receiver position deviations thereby seriously compromising the performance of satellite‐based navigation system. Results from the anomaly crest station at Calcutta indicate maximum 40% of scintillation time during February–April 2014 and 33% during August–October 2014 that the signals are decorrelated. It is important to note that it is only during these time intervals that the principle of frequency diversity could be applied for scintillation mitigation.
Analysis of Waveguide Devices Involving Lateral and Transverse Perfect Magnetic Wall Boundary Conditions by the Mode‐Matching Method
Authors: Polo‐López Lucas , Ruiz‐Cruz Jorge A. , Montejo‐Garai José R. , Rebollar Jesús M. 
Published: September 2017

AbstractThis contribution presents the analysis of waveguide problems involving general boundary conditions of perfect magnetic wall. This type of boundary condition is used in electromagnetic solvers very commonly when the device under analysis has physical symmetry, in order to speed up the computation time. This paper is focused on extending its use in problems having this type of boundary condition in the lateral and transverse walls of the waveguides involved in the problem. The presented formulation, based on the mode‐matching method, will be applied to classical waveguide devices, but also to address radiating problems with a novel formulation. Different applications will be targeted, and the simulation results will be compared with those obtained by other numerical techniques (based on different solvers), validating the presented approach as another suitable tool for computer‐aided design.
Stimulus–Response Model
Authors: Esser Frank 
Published: September 2017

The stimulus–response model is associated with the assumption that the mass media has powerful effects. Also referred to as the “hypodermic needle theory,” “transmission belt theory,” or “magic bullet theory,” it can be considered one of the first general conceptions describing mass media effects (→ Media Effects, History of). Lowery and DeFleur ([Lowery, S. A., 1995]) summarized the basic assumptions behind the stimulus–response or hypodermic needle theory as follows: (1) people in a mass society lead socially isolated lives, exerting very limited social control over each other because they have diverse origins and do not share a unifying set of norms, values, and beliefs; (2) similar to higher animals, human beings are endowed at birth with a uniform set of instincts that guide their ways of responding to the world around them; (3) because people's actions are not influenced by social ties and are guided by uniform instincts, individuals attend to events (such as media messages) in similar ways; and (4) people's inherited human nature and their isolated social condition lead them to receive and interpret media messages in a uniform way.
Desymmetrization of Cyclopentenediones via Organocatalytic Cross‐Dehydrogenative Coupling
Authors: Vetica Fabrizio , Bailey Stephen , Chauhan Pankaj , Turberg Mathias , Ghaur Adjmal , Raabe Gerhard , Enders Dieter 
Published: September 2017

AbstractAn enantioselective synthesis of cyclopentenediones bearing a pyrazole unit has been achieved through an organocatalytic Michael addition/oxidation process. This desymmetrization reaction led to the desired pyrazole‐cyclopentenediones with high yield and good enantioselectivities. The postulated cross‐dehydrogenative coupling‐mechanism has been investigated via preliminary control experiments.magnified image
Reversible DNA–Protein Cross‐Linking at Epigenetic DNA Marks
Authors: Ji Shaofei , Shao Hongzhao , Han Qiyuan , Seiler Christopher L. , Tretyakova Natalia Y. 
Published: September 2017

Abstract5‐Formylcytosine (5fC) is an endogenous DNA modification frequently found within regulatory elements of mammalian genes. Although 5fC is an oxidation product of 5‐methylcytosine (5mC), the two epigenetic marks show distinct genome‐wide distributions and protein affinities, suggesting that they perform different functions in epigenetic signaling. A unique feature of 5fC is the presence of a potentially reactive aldehyde group in its structure. Herein, we show that 5fC bases in DNA readily form Schiff‐base conjugates with Lys side chains of nuclear proteins in vitro and in vivo. These covalent protein–DNA complexes are reversible (t1/2=1.8 h), suggesting that they contribute to transcriptional regulation and chromatin remodeling. On the other hand, 5fC‐mediated DNA–protein cross‐links, if present at replication forks or actively transcribed regions, may interfere with DNA replication and transcription.
Construction and application of an electrochemical biosensor based on an endotoxin aptamer
Authors: Ying GuoQing , Wang MinJun , Yi Yu , Chen JianShu , Mei JianFeng , Zhang YanLu , Chen ShuQing 
Published: September 2017

AbstractAn electrochemical biosensor that used an aptamer as a biological element was constructed to detect endotoxin. Biolayer interferometry was used to obtain the affinity constant of an aptamer for lipopolysaccharide, which had an equilibrium dissociation constant of 22.9 nM. The amine‐terminated aptamer was then assembled on a gold electrode surface using 3‐mercaptopropionic acid as an intermediate linker. The modification of the gold electrode was confirmed by cyclic voltammetry and electrochemical impedance spectroscopy. In the range of 0.001–1 EU/mL, the increase in electron transfer resistance of the biosensor was linear with the logarithmic value of the endotoxin concentration. The constructed biosensor exhibits sensitivity and a low limit of detection.
Robust Multi‐Objective Global Optimization of Stochastic Processes With a Case Study in Gradient Elution Chromatography
Authors: Freier Lars , von Lieres Eric 
Published: September 2017

AbstractA novel algorithm for robust multi‐objective process optimization under stochastic variability of environmental variables is introduced and applied to a case study in gradient elution chromatography. Process variability is accounted for by simultaneously optimizing several scenarios with random but fixed values of the environmental variables. These iterative optimizations are synchronized by planning the same experiments for all scenarios. Experiments are designed by maximizing the cumulative expected hypervolume improvement as predicted by several Gaussian process regression models. A straightforward method is presented for estimating the expected Pareto front and its variability based on the resulting data that maintains traceability of the corresponding process parameters. This information is required for robust process optimization, that is, determination of Pareto optimal processes that fulfil specific minimal criteria with a certain confidence. The presented algorithm can generally be applied to both in silico and wet lab experiments but involves an increased experimental effort as compared to the deterministic case.
Anterior cingulate cortex involved in social food‐foraging decision‐making strategies of rats
Authors: Zhong Xiaolin , Deng Sihao , Ma Wenbo , Yang Yuchen , Lu Dahua , Cheng Na , Chen Dan , Wang Hui , Zhang Jianyi , Li Fang , Li Changqi , Huang Hua‐Lin , Li Zhiyuan 
Published: September 2017

AbstractIntroductionDecision making as a complex cognitive process involves assessing risk, reward, and costs. Typically, it has been studied in nonsocial contexts. We have developed a novel laboratory model used with rodents to detect food‐foraging decision‐making strategies in different social settings. However, the brain regions that mediate these behaviors are not well identified. Substantial evidence shows that the anterior cingulate cortex (ACC) participates in evaluation of social information and in decision making.MethodsIn this study, we investigated the effect of bilateral lesions in the ACC on established behaviors. Kainic acid (KA) was administered bilaterally to induce ACC lesions, and saline microinjection into the ACC was used in the sham group.ResultsIn contrast to the sham‐lesioned animals, when faced with the choice of foraging under a social context, rats with ACC lesions preferred foraging for the less desirable food. Moreover, in these situations, the total amount of food foraged by the ACC‐lesioned group was less than the amount foraged by the sham group. Notably, neither social interactions nor social agonistic behaviors were affected by ACC lesions.ConclusionsThese data suggest that the ACC is a key region underlying neural processing of social decision‐making, specifically tending to compete for foraging high predictive reward food.
Split high‐dose oral levothyroxine treatment as a successful therapy option in myxedema coma
Authors: Charoensri Suranut , Sriphrapradang Chutintorn , Nimitphong Hataikarn 
Published: September 2017

Key Clinical MessageHigh‐dose intravenous thyroxine (T4) is the preferable treatment for myxedema coma. We describe the clinical course of a 69‐year‐old man who presented with myxedema coma and received oral levothyroxine (LT4) therapy (1 mg) in a split dose. This suggests split high‐dose oral LT4 as a therapeutic option in myxedema coma.
Hydrogen Peroxide Assisted Selective Oxidation of 5‐Hydroxymethylfurfural in Water under Mild Conditions
Authors: Chen Ching‐Tien , Nguyen Chi Van , Wang Zheng‐Yen , Bando Yoshio , Yamauchi Yusuke , Bazziz Manar Tareq Saleh , Fatehmulla Amanullah , Farooq W. Aslam , Yoshikawa Takuya , Masuda Takao , Wu Kevin C.‐W. 
Published: September 2017

AbstractAn effective and selective method for the oxidation of 5‐hydroxymethylfurfural (HMF) by using hydrogen peroxide (H2O2) as the liquid oxygen source and activated‐carbon‐supported ruthenium (Ru/AC) as the catalyst was developed. This reaction system allowed HMF to be oxidized in water under mild reaction conditions efficiently, as it was shown to have lower mass‐transfer resistance than gaseous oxygen‐assisted oxidation systems. In addition, we could selectively control the components of the oxidation products by adjusting the reaction conditions. We optimized several reaction parameters such as the reaction temperature (75 °C), time (t=1 or 6 h), base additive (sodium carbonate), and the HMF/catalyst ratio (50 or 10) to attain the desired products in maximum yields. Thus, 5‐formyl‐2‐furoic acid was obtained in a high yield up to 92 % with a HMF/catalyst ratio of 50 and a reaction time of 1 h, whereas 2,5‐furandicarboxylic acid was obtained in a maximum yield of 91.3 % with a HMF/catalyst ratio of 10 and a reaction time of 6 h. A possible mechanism for the selective oxidation of HMF was also discussed. We envision that the H2O2‐mediated oxidation systems proposed in this study would be of great benefit to other organic oxidation systems.
Unidirectional growth of heavy meromyosin clusters along actin filaments revealed by real‐time fluorescence microscopy
Authors: Hirakawa Rika , Nishikawa Yusuke , Uyeda Taro Q.P. , Tokuraku Kiyotaka 
Published: September 2017

AbstractHeavy meromyosin (HMM) forms clusters along actin filaments under low ATP concentrations. Here, we observed the growth of HMM clusters under low concentrations of ATP in real time using fluorescence microscopy. When actin filaments were loosely immobilized on positively charged lipid bilayers, clusters of HMM‐GFP were readily formed. Time‐lapse observation revealed that the clusters grew unidirectionally. When we used a mixture of actin filaments and copolymers of actin and acto‐S1dC, a chimeric protein of actin and the myosin motor domain, HMM‐GFP preferentially formed clusters along the copolymers. We thus suggest that binding of myosin motors carrying ADP and Pi induces unidirectional conformational changes in actin filaments and allosterically recruits more myosin binding. In contrast, when actin filaments and copolymers were anchored to glass substrate via stable biotin‐avidin linkage, higher concentrations of HMM‐GFP were required to form clusters than on the lipid bilayer. Moreover, actin filaments and copolymers were not discriminated regarding preferential cluster formation. This is presumably because the myosin‐induced cooperative conformational changes in actin filaments involve changes in the helical twist. Consistent with this, cofilin clusters, which supertwist the helix, were readily formed along loosely immobilized actin filaments, but not along those anchored via biotin‐avidin linkage.
Fluorophore Release from a Polymethinic Photoremovable Protecting Group Through a Nonlinear Optical Process
Authors: Rodríguez‐Romero Jesús , Guarin Cesar A. , Arroyo‐Pieck Andres , Gutiérrez‐Arzaluz Luis , López‐Arteaga Rafael , Cortés‐Guzmán Fernando , Navarro Pedro , Peon Jorge 
Published: September 2017

AbstractThe front cover artwork is provided by members of the Instituto de Química at Universidad Nacional Autónoma de México (UNAM). The image represents a spatially localized photochemical cleavage induced by two‐photon absorption of NIR ultrashort laser pulses. A highly fluorescent species is formed in the process. Read the full text of the Article at 10.1002/cptc.201700076.
Atom‐Transfer Radical Addition to Unactivated Alkenes by using Heterogeneous Visible‐Light Photocatalysis
Authors: Mao Liang‐Liang , Cong Huan 
Published: September 2017

AbstractHeterogeneous visible‐light photocatalysis represents an important route toward the development of sustainable organic synthesis. In this study visible light‐induced, heavy metal‐free atom‐transfer radical addition to unactivated terminal olefins is carried out by using the combination of heterogeneous titanium dioxide as photocatalyst and a hypervalent iodine(III) reagent as co‐initiator. The reaction can be applied to a range of substrates with good functional‐group tolerance under very mild conditions. In addition to a number of commonly used atom‐transfer reagents, the relatively challenging chloroform is also suitable.
Glucocorticoid treatment earlier in childhood and adolescence show dose‐response associations with diurnal cortisol levels
Authors: Vestergaard Martin , Holm Sara K. , Uldall Peter , Siebner Hartwig R. , Paulson Olaf B. , Baaré William F.C. , Madsen Kathrine S. 
Published: September 2017

AbstractHeightened levels of glucocorticoids in children and adolescents have previously been linked to prolonged changes in the diurnal regulation of the stress‐hormone cortisol, a glucocorticoid regulated by the hypothalamic‐pituitary‐adrenal‐axis (HPA‐axis). To address this question, we examined the salivary cortisol awakening response (CAR) and daily cortisol output in 36 children and adolescents (25 girls/11 boys) aged 7–16 years previously treated with glucocorticoids for nephrotic syndrome or rheumatic disorder and 36 healthy controls. Patients and controls did not significantly differ in the CAR or diurnal cortisol output; however, sex‐dependent group differences were observed. Specifically, female patients had a higher CAR relative to female controls, while male patients had higher daily cortisol levels compared to male controls. Notably, CAR in female patients and daily cortisol levels in male patients showed a positive linear relationship with the mean daily glucocorticoid doses administered during treatment. The observed dose‐response associations suggest that glucocorticoid therapy during childhood and adolescence might trigger long‐term changes in HPA‐axis regulation, which may differ for males and females.
Toddler hand preference trajectories predict 3‐year language outcome
Authors: Nelson Eliza L. , Gonzalez Sandy L. , Coxe Stefany , Campbell Julie M. , Marcinowski Emily C. , Michel George F. 
Published: September 2017

AbstractA growing body of work suggests that early motor experience affects development in unexpected domains. In the current study, children's hand preference for role‐differentiated bimanual manipulation (RDBM) was measured at monthly intervals from 18 to 24 months of age (N = 90). At 3 years of age, children's language ability was assessed using the Preschool Language Scales 5th edition (PLS™‐5). Three distinct RDBM hand preference trajectories were identified using latent class growth analysis: (1) children with a left hand preference but a moderate amount of right hand use; (2) children with a right hand preference but a moderate amount of left hand use; and (3) children with a right hand preference and only a mild amount of left hand use. Stability over time within all three trajectories indicated that children did not change hand use patterns from 18 to 24 months. Children with the greatest amount of preferred (i.e., right) hand use demonstrated higher expressive language scores compared to children in both trajectories with moderate levels of non‐preferred hand use. Children with the greatest amount of right hand use also had higher scores for receptive language compared to children with a right hand preference but moderate left hand use. Results support that consistency in handedness as measured by the amount of preferred hand use is related to distal language outcomes in development.
Origins of the Greenland shark (Somniosus microcephalus): Impacts of ice‐olation and introgression
Authors: Walter Ryan P. , Roy Denis , Hussey Nigel E. , Stelbrink Björn , Kovacs Kit M. , Lydersen Christian , McMeans Bailey C. , Svavarsson Jörundur , Kessel Steven T. , Biton Porsmoguer Sebastián , Wildes Sharon , Tribuzio Cindy A. , Campana Steven E. , Petersen Stephen D. , Grubbs R. Dean , Heath Daniel D. , Hedges Kevin J. , Fisk Aaron T. 
Published: September 2017

AbstractHerein, we use genetic data from 277 sleeper sharks to perform coalescent‐based modeling to test the hypothesis of early Quaternary emergence of the Greenland shark (Somniosus microcephalus) from ancestral sleeper sharks in the Canadian Arctic‐Subarctic region. Our results show that morphologically cryptic somniosids S. microcephalus and Somniosus pacificus can be genetically distinguished using combined mitochondrial and nuclear DNA markers. Our data confirm the presence of genetically admixed individuals in the Canadian Arctic and sub‐Arctic, and temperate Eastern Atlantic regions, suggesting introgressive hybridization upon secondary contact following the initial species divergence. Conservative substitution rates fitted to an Isolation with Migration (IM) model indicate a likely species divergence time of 2.34 Ma, using the mitochondrial sequence DNA, which in conjunction with the geographic distribution of admixtures and Pacific signatures likely indicates speciation associated with processes other than the closing of the Isthmus of Panama. This time span coincides with further planetary cooling in the early Quaternary period followed by the onset of oscillating glacial‐interglacial cycles. We propose that the initial S. microcephalus–S. pacificus split, and subsequent hybridization events, were likely associated with the onset of Pleistocene glacial oscillations, whereby fluctuating sea levels constrained connectivity among Arctic oceanic basins, Arctic marginal seas, and the North Atlantic Ocean. Our data demonstrates support for the evolutionary consequences of oscillatory vicariance via transient oceanic isolation with subsequent secondary contact associated with fluctuating sea levels throughout the Quaternary period—which may serve as a model for the origins of Arctic marine fauna on a broad taxonomic scale.