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Background Transnasal endoscopy presents a technical difficulty when inserting the flexible endoscope. It is unclear whether a particular breathing method is useful for transnasal endoscopy. Therefore, we conducted a prospective randomized controlled trial to compare endoscopic operability and patient tolerance between patients assigned to nasal breathing or oral breathing groups. Methods 198 eligible patients were randomly assigned to undergo transnasal endoscopy with nasal breathing or with oral breathing. Endoscopists and patients answered questionnaires on the endoscopic operability and patient tolerance using a 100-mm visual analog scale ranging from 0 (non-existent) to 100 (most difficult/unbearable). The visibility of the upper-middle pharynx was recorded. Results Patient characteristics did not differ significantly between the groups. Nasal breathing showed a higher rate of good visibility of the upper-middle pharynx than oral breathing (91.9 % vs. 27.6 %; P Conclusions Nasal breathing is superior to oral breathing for those performing and undergoing transnasal endoscopy. Nasal breathing led to good visibility of the upper-middle pharynx, improved endoscopic operability, and better patient tolerance, and was safer owing to decreased pharyngeal bleeding.

Silicon oxide atomic layer deposition synthesis development over the last few years has open the route to its use as a dielectric within diamond electronics. Its great band-gap makes it a promising material for the fabrication of diamond-metal-oxide field effects transistor gates. Having a sufficiently high barrier both for holes and electrons is mandatory to work in accumulation and inversion regimes without leakage currents, and no other oxide can fulfil this requisite due to the wide diamond band-gap. In this work, the heterojunction of atomic-layer-deposited silicon oxide and (100)-oriented p-type oxygen-terminated diamond is studied using scanning transmission electron microscopy in its energy loss spectroscopy mode and X-ray photoelectron spectroscopy. The amorphous phase of silicon oxide was successfully synthesized with a homogeneous band-gap of 9.4 eV. The interface between the oxide and diamond consisted mainly of single- and double-carbon-oxygen bonds with a low density of interface states and a straddling band setting with a 2.0 eV valence band-offset and 1.9 eV conduction band-offset.

Unique morphologies were found in binary and ternary polymer blended particles, including Ashura-type phase separation, which has three different polymer components on the particle surface. The morphologies of phase-separated structures in the binary polymer blended particles are discussed in terms of the surface tensions of the blended polymers. Structural control of ternary polymer blended particles was achieved based on the combination of polymers by examining binary polymer blended particles. A theoretical approach based on the Cahn-Hilliard equations gives identical morphologies with the experimental results. This work opens the way to creating polymer particles with sophisticated nanostructures by controlling their morphologies as predicted by theoretical simulations.

We analyse pinned front and pulse solutions in a singularly perturbed three-component FitzHugh–Nagumo model with a small jump-type heterogeneity. We derive explicit conditions for the existence and stability of these type of pinned solutions by combining geometric singular perturbation techniques and an action functional approach. Most notably, in certain parameter regimes we can explicitly compute the pinning distance of a localised solution to the defect.

Annealing of block copolymers has become a tool of great importance for the reconfiguration of nanoparticles. Here, we present the experimental results of annealing block copolymer nanoparticles and a theoretical model to describe the morphological transformation of ellipsoids with striped lamellae into onionlike spheres. A good correspondence between the experimental findings and predictions of the model was observed. The model based on finding the steepest direction of descent of an appropriate free energy leads to a set of Cahn-Hilliard equations that correctly describe the dynamical transformation of striped ellipsoids into onionlike spheres and reverse onionlike particles, regardless of the nature of the annealing process. This universality makes it possible to describe a variety of experimental conditions involving nanoparticles underlying a heating process. A notable advantage of the proposed approach is that it enables selective control of the interaction between the confined block copolymer and the surrounding medium. This feature endows the model with a great versatility to enable the reproduction of several combined effects of surfactants in diverse conditions, including cases with reverse affinities for the block copolymer segments. A phase diagram to describe a variety of morphologies is presented. We employ the relationship between the temperature-dependent Flory-Huggins parameter and the width of the interfaces to account for changes in temperature due to the heating process. Simulation results correctly show how the transformation evolves as the temperature increases. This increment in temperature corresponds to progressively smaller values of the interfacial width. We anticipate that the proposed approach will facilitate the design and more precise control of experiments involving various kinds of annealing processes.

In this article, we use geometric singular perturbation techniques combined with an action functional approach to study pinned pulse solutions in a three-component FitzHugh–Nagumo model with a bump-type heterogeneity. We show that the model in the original activator-2 inhibitor framework only supports symmetric pinned pulse solutions that are located in the middle of the bump region. In contrast, asymmetric pinning is possible for parameters not in the activator-2 inhibitor framework.

International audience; Atomic layer etching (ALE) of Ga-polar GaN (0001) using a standard inductively coupled plasma-reactive ion etching system is achieved in this work. The sequential process is using Cl2 to modify the surface in the adsorption step. For the activation step, the authors compare two rare gas plasmas, namely, Ar and Kr, and show a much larger and well-defined ALE window for the latter. The ALE of GaN is demonstrated by etching mesa structures masked with a photoresist. A constant etching rate per cycle of two monolayers is obtained. The experimental conditions of this self-limited process are found by changing both the adsorption and activation times, together with the source power. This provides an atomic-scale process for nanofabrication, with significant improvements to the GaN surface.

The thermal atomic layer deposition (ThALD) of yttrium oxide (Y2O3) was developed using the newly designed, liquid precursor, Y(EtCp)2(iPr2-amd), as the yttrium source in combination with different oxygen sources, such as ozone, water and even molecular oxygen. Saturation was observed for the growth of the Y2O3 films within an ALD window of 300 to 450 °C and a growth per cycle (GPC) up to 1.1 Å. The resulting Y2O3 films possess a smooth and crystalline structure, while avoiding any carbon and nitrogen contamination, as observed by X-ray photoelectron spectroscopy (XPS). The films showed strong resistance to fluorine-containing plasma, outperforming other resistant materials, such as silicon oxide, silicon nitride and alumina. Interestingly, the hydrophilic character exhibited by the film could be switched to hydrophobic after exposure to air, with water contact angles exceeding 90°. After annealing under N2 flow at 600 °C for 4 min, the hydrophobicity was lost, but proved recoverable after prolonged air exposure or intentional hydrocarbon exposure. The origin of these changes in hydrophobicity was examined.

In this manuscript, we combine geometrical singular perturbation techniques and an action functional to revisit—and further study—the existence and stability of stationary localized structures in a singularly perturbed three-component FitzHugh–Nagumo model. In particular, the action functional replaces the Melnikov integral approach used in Doelman et al. (J Dyn Differ Equ 21:73–115, 2009) to explicitly derive existence conditions for stationary localized structures. In addition, the action functional also gives critical information on the stability of these stationary localized structures, thus circumventing a tedious Evans function computation. This highlights the strength of the action functional approach.

The ability to continue flowering after loss of inductive environmental cues that trigger flowering is termed floral commitment. Reversible transition involving a switch from floral development back to vegetative development has been found in Arabidopsis mutants and many plant species. Although the molecular basis for floral commitment remains unclear, recent studies suggest that the persistent activity of FLOWERING LOCUS T (FT) at inflorescences is required for floral commitment in Arabidopsis thaliana. Because FT encodes a mobile signal, florigen, which is generally transported from leaves to meristems through the phloem, understanding the transportation dynamics of FT is required to explore the role of FT on floral commitment. Here we developed a transportation model of leaf- and inflorescence-derived florigen and sucrose based on pressure-flow hypothesis. Depending on the demanded level of florigen supply for floral commitment of each floral meristem, the model predicted the change in inflorescence pattern from stable commitment to flower, transient flowering, and complete reversion. FT activity in inflorescence partly suppressed floral reversion, but complete suppression was achieved only when inflorescence became a source of sucrose. This finding highlights the importance of monitoring the spatio-temporal sucrose distribution and floral stimulus to understand inflorescence development mechanism.

In order to qualitatively and quantitatively analyze the effects of N source impurity species and concentrations on the properties of epitaxial GaN layers, we intentionally introduced the oxygen-containing species CO and CO2 into GaN layers during growth. Subsequently, we determined the impurities or elements that had a strong effect on the photoelectric properties of the GaN layers and investigated the doping mechanism. The results of this study show that changes in the carrier density are more sensitive to CO2 than to CO. Oxygen as the main donor was found to affect the carrier density and photoluminescence (PL) emission intensities of CO and CO2-doped GaN, and the carbon incorporation efficiency of these molecules was found to be lower than the oxygen incorporation efficiency. In order to obtain ideal epitaxial GaN layers with a reduced carrier density of 1013 cm−3, the CO and CO2 concentrations in the ammonia source should be less than 100 ppb (CO) and 10−1 ppb (CO2).

The dynamics of pulse solutions in a bistable reaction-diffusion system are studied analytically by reducing partial differential equations (PDEs) to finite-dimensional ordinary differential equations (ODEs). For the reduction, we apply the multiple-scales method to the mixed ODE-PDE system obtained by taking a singular limit of the PDEs. The reduced equations describe the interface motion of a pulse solution formed by two interacting front solutions. This motion is in qualitatively good agreement with that observed for the original PDE system. Furthermore, it is found that the reduction not only facilitates the analytical study of the pulse solution, especially the specification of the onset of local bifurcations, but also allows us to elucidate the global bifurcation structure behind the pulse behavior. As an application, the pulse dynamics in a heterogeneous bump-type medium are explored numerically and analytically. The reduced ODEs clarify the transition mechanisms between four pulse behaviors that occur at different parameter values., 60 pages, 8 figures

We consider the mixed ODE-PDE system called a hybrid system, in which the two interfaces interact with each other through a continuous medium and their equations of motion are derived in a weak interaction framework. We study the bifurcation property of the resulting hybrid system and construct an unstable standing pulse solution, which plays the role of a separator for dynamic transition from standing breather to annihilation behavior between two interfaces.

Heterogeneity is one of the most important and ubiquitous types of external perturbations. We study a spontaneous pulse-generating mechanism in an excitable medium with jump-type heterogeneity. Such a pulse generator (PG) has attracted considerable interest due to the computational potential of pulse waves in physiological signal processing. We first investigate the conditions for the onset of robust-type PGs, and then we show the global bifurcation structure of heterogeneity-induced patterns, including the complex ordered sequence of pulse-generating manners. We devise numerical frameworks to trace the long-term behavior of PGs as periodic solutions, and we detect the associated terminal homoclinic orbits that are homoclinic to a special type of heterogeneity-induced ordered pattern with a hyperbolic saddle. These numerical approaches assist us in identifying a candidate for the organizing center, and producing a variety of PGs as a codimension-two gluing bifurcation, in which two homoclinic trajectories...

Immunohistochemical data (IHC) plays an important role in clinical practice, and is typically gathered in a semi-quantitative fashion that relies on some degree of visual scoring. However, visual scoring by a pathologist is inherently subjective and manifests both intra-observer and inter-observer variability. In this study, we introduce a novel computer-aided quantification methodology for immunohistochemical scoring that uses the algebraic concept of persistent homology. Using 8 bit grayscale image data derived from 90 specimens of invasive ductal carcinoma of the breast, stained for the replicative marker Ki-67, we computed homology classes. These were then compared to nuclear grades and the Ki-67 labeling indices obtained by visual scoring. Three metrics for IHC staining were newly defined: Persistent Homology Index (PHI), center coordinates of positive and negative groups, and the sum of squares within groups (WSS). This study demonstrates that PHI, a novel index for immunohistochemical labeling using persistent homology, can produce highly similar data to that generated by a pathologist using visual evaluation. The potential benefits associated with our novel technology include both improved quantification and reproducibility. Since our method reflects cellularity and nuclear atypia, it carries a greater quantity of biologic data compared to conventional evaluation using Ki-67.

We consider the dynamics of two interfaces that interact through a continuous medium with spatial heterogeneity. The dynamics of interface positions is governed by ordinary differential equations (ODEs), whereas that of the continuous field by a partial differential equation. The resulting mixed ODE-PDE system, which we call a hybrid system (HS), is derived as a singular limit of a certain bistable reaction-diffusion system (PDE), describing the dynamics of traveling pulses of front-back type. First, the traveling pulse dynamics in the heterogeneous medium is numerically studied both for the bistable reaction-diffusion system and for the hybrid system. Then, the hybrid system is analyzed to clarify the underlying mechanisms for the pulse behavior observed. In particular, we carry out a center manifold reduction for the hybrid system, which reveals not only the supercriticality of Hopf bifurcations but also the mechanism for sliding motion of an oscillating pulse observed in the heterogeneous medium.

We numerically study a set of coupled Cahn-Hilliard equations as a means to find morphologies of diblock copolymers in three-dimensional spherical confinement. This approach allows us to find a variety of energy minimizers including rings, tennis balls, Janus balls and multipods among several others. Phase diagrams of confined morphologies are presented. We modify the size of the interface between microphases to control the number of holes in multipod morphologies. Comparison to experimental observation by transmission electron microtomography of multipods in polystyrene-polyisoprene diblock copolymers is also presented.

Spatially localized patterns form a representative class of patterns in dissipative systems. We study how the dynamics of traveling spots in two-dimensional space change when heterogeneities are introduced in the media. The simplest but fundamental one is a line heterogeneity of jump type. When spots encounter the jump, they display various outputs including penetration, rebound, and trapping depending on the incident angle and its height. The system loses translational symmetry by the heterogeneity, but at the same time, it causes the emergence of various types of heterogeneity-induced-ordered-patterns (HIOPs) replacing the homogeneous constant state. We study these issues by using a three-component reaction-diffusion system with one activator and two inhibitors. The above outputs can be obtained through the interaction between the HIOPs and the traveling spots. The global bifurcation and eigenvalue behavior of HISPs are the key to understand the underlying mechanisms for the transitions among those dynamics. A reduction to a finite dimensional system is presented here to extract the model-independent nature of the dynamics. Selected numerical techniques for the bifurcation analysis are also provided.

The article Pinned Solutions in a Heterogeneous Three-Component FitzHugh–Nagumo Model, written by Peter van Heijster, Chao-Nien Chen, Yasumasa Nishiura and Takashi Teramoto, was originally published electronically on the publisher’s internet portal (currently SpringerLink) on August 11, 2018, without open access.

Our subject is the diblock copolymer problem in a three-dimensional space. Using numerical simulations, the double gyroid and orthorhombic morphologies are obtained as energy minimizers. By investigating the geometric properties of these bicontinuous morphologies, we demonstrate the underlying mechanism affecting the triply periodic energy minimizers in terms of a balanced scaling law. We also apply computational homology to their characterization during the dynamics of morphology transition. Our topological approaches detect the morphology of transient perforated layers as they transition from layers to cylinders, and the t^[-1] law of the Betti number in the phase ordering process.

Prior research shows that in-store displays have a significant effect on product sales, but no study so far has measured this effect using a qualitative approach that considers the size of the in-store display or its general theme. In this study, a smartphone-based user generated contents (UGC) was used to encourage consumers to post about the in-store displays they liked. This study investigates the relationship between the qualitative content of in-store displays and the sales of the products featured in such displays, and the relationship between posts or likes and the sales of the products featured in the posted liked display. We examine the effects of the contents of in-store display on sales and the mediation effect of the POST or LIKE on these relationship. As the result, this study is the first to explicate the difference of the mediation effect of post on sales by the type of the content of the in-store display. Specifically, the following three aspects were elucidated: (1) “Seasonality” drives user posting on UGC and such posts contribute to increased sales, (2) “Mass” both directly contributes to increased sales and also promotes user postings on UGC, which contribute to increase sales, and (3) “Character” directly influences sales but does not contribute to sales through postings. This study also provides important managerial implications. The results highlight the role of the content of in-store displays in promoting sales. Specifically, if the goal is to simply increase sales, a character themed in-store display will suffice. If the goal is to induce postings to UGC, which will result in increased sales, then a seasonally themed in-store display will work. In this way, expanding consideration to the qualities of in-store displays makes it possible to develop a more strategic understanding of their effects rather than the simple on/off or numerical frequency approach of the past. It must be taken into account that the type of in-store display content that is called for will differ according to whether the objective is to simply increase sales or to also attempt to create WOM promotion.

In recent years, it appears that the process in which the consumer obtains information on a new product, recognizes the product and then puts it in his or her consideration set as a candidate for purchase is changing along with the popularity of Twitter, Facebook and other SNSs. The new flow is for the consumer to identify a given product as a candidate for purchase not only through recognition but also after talking about it with acquaintances and friends and realizing that: “The person I trust ‘likes’ the product,” “Everyone is talking about the product” and the like. It is also considered that information-leader types of consumers, who are good at creating topics of conversation, have a greater tendency to make a given product a candidate for purchase. Given the above, this study focused on the ability of the information-leader group to create topics of conversation and revealed how their recognition of a new product and their talk about it actually affected their purchase decision-making. Actual analysis found that a key to a given product being considered more as a candidate for purchase was for the product to be talked about, particularly among consumers who are like information leaders. For a company to introduce a new product and make consumers identify it as a candidate for purchase, it is necessary to implement a communication strategy that starts with the creation of topics of conversation by consumers who are like information leaders and considers how to make them talk about the product.

Scattering process between traveling breathers (TBs) is studied for the complex Ginzburg-Landau equations (CGLE) with a parametric forcing term. The phase-dependency of the input-output relation can be explained from the scattor's viewpoint. In this note, we especially focus on the issue for the asymmetric head-on collisions, i.e., the phases of two colliding TBs are different.

Scattering of particle-like patterns in dissipative systems is studied, especially we focus on the issue how the input–output relation is controlled at a head-on collision where traveling pulses or spots interact strongly. It remains an open problem due to the large deformation of patterns at a colliding point. We found that a special type of unstable steady or time-periodic solutions called scattors and their stable and unstable manifolds direct the traffic flow of orbits. Such scattors are in general highly unstable even in the one-dimensional case which causes a variety of input–output relations through the scattering process. We illustrate the ubiquity of scattors by using the complex Ginzburg–Landau equation, the Gray–Scott model, and a three-component reaction diffusion model arising in gas-discharge phenomena.

Addition of hydrophobic guest molecule (C12H26) into the nonionic surfactant/water system (C16E7/D2O) system modifies the phase behavior between the lamellar and column phases. The distribution of the added guest molecule in the microstructure and the interfacial structure is examined by using a small angle neutron scattering technique. The characteristic length and the interfacial thickness of the microstructure are deformed in order to optimize the distribution of the guest molecules. The obtained experimental results including the existence of the double gyroid and rhombohedral phases are in agreement with those of the simple model of diblock copolymers.

The richness of spatial structures of the diblock copolymer melts is demonstrated by the minimization of a free-energy functional of nonlocal type. The total chain length and the interface thickness are key factors in determining the morphology of the system, in addition to the constant mean curvature surface ansatz. We examine the transition between lamellar and double gyroid phases, in which the rhombohedral phase is also obtained in the weak segregation regime.

Application of the Saeki method [J. Phys. Soc. Jpn. 69 (2000) 679] to copolymer–homopolymer mixtures using the free energy proposed by Ohta and Ito [Phys. Rev. E 52 (1995) 5250] reveals the complicated three-dimensional morphologies, such as onion, helices and regular polyhedral structures.

The main purpose of this paper is to make it clear that the physical value obtained along the trajectory generated by the new numerical scheme [J. Phys. Soc. Jpn. 69 (2000) 679.] satisfies the canonical distribution. On the basis of our proof, the scattering form factors are evaluated from the time evolution of the spatial pattern that fluctuates around the equilibrium lamellar pattern. Beyond critical values of temperature, the transitions from a lamellar pattern to hexagonal and isotropic patterns occur in the vicinity of the morphological transition point.

The present study was performed to examine changes in the arrangement of D-periodic collagen fibrils in the synovium of the growing temporomandibular joint in mice. At 1 week of age, the mandibular condyle was undeveloped, and only a few collagen fibrils were recognizable in the subintimal layer of the synovium. At 8 weeks, the mandibular condyle was structurally developed with an increase of collagen fibrils in the synovium; a fully mature condyle was observed at 6 months of age. The close association of proteoglycans with collagen fibrils in the synovium of the growing joint was examined by both conventional and energy-filtering transmission electron microscopy of cupromeronic blue-stained specimens. Proteoglycans were associated with D-periodic collagen fibrils in the short filamentous form in random fashion at 1 week of age, but in a regular pattern with D-periodicity at 6 months. These associations in the synovium could be correlated with the mechanical character of the temporomandibular joint.

The purpose of this letter is to propose an efficient numerical scheme to obtain the equilibrium pattern in a block copolymer system. Using this scheme, one can obtain well-defined periodic patterns from numerical simulations with a small amount of computational effort. This method is extended to the control of the fluctuations around the equilibrium pattern by keeping the kinetic energy of the system at a constant value.

Heterogeneity is one of the most important and ubiquitous types of external perturbations. We study a spontaneous pulse generating mechanism caused by the heterogeneity of jump type. Such a pulse generator (PG) has attracted much interest in relation to potential computational abilities of pulse waves in physiological signal processing. Exploring the global bifurcation structure of PGs as periodic solutions, we find firstly the conditions under which they emerge, i.e., the onset of PGs, secondly a candidate for the organizing center producing a variety of PGs.