bluuebunny/crossref_metadata_2025_split huggingface dataset:
Electrogenic transport and K+ ion channel expression by the human endolymphatic sac epithelium
Authors: Kim Sung Huhn , Kim Bo Gyung , Kim Jin Young , Roh Kyung Jin , Suh Michelle J. , Jung JinSei , Moon In Seok , Moon Sung K. , Choi Jae Young 
Published: December 2015

AbstractThe endolymphatic sac (ES) is a cystic organ that is a part of the inner ear and is connected to the cochlea and vestibule. The ES is thought to be involved in inner ear ion homeostasis and fluid volume regulation for the maintenance of hearing and balance function. Many ion channels, transporters and exchangers have been identified in the ES luminal epithelium, mainly in animal studies, but there has been no functional study investigating ion transport using human ES tissue. We designed the first functional experiments on electrogenic transport in human ES and investigated the contribution of K+ channels in the electrogenic transport, which has been rarely identified, even in animal studies, using electrophysiological/pharmacological and molecular biological methods. As a result, we identified functional and molecular evidence for the essential participation of K+ channels in the electrogenic transport of human ES epithelium. The identified K+ channels involved in the electrogenic transport were KCNN2, KCNJ14, KCNK2 and KCNK6 and the K+ transports via those channels are thought to play an important role in the maintenance of the unique ionic milieu of the inner ear fluid.
Long-term xeno-free culture of human pluripotent stem cells on hydrogels with optimal elasticity
Authors: Higuchi Akon , Kao Shih-Hsuan , Ling Qing-Dong , Chen Yen-Ming , Li Hsing-Fen , Alarfaj Abdullah A. , Munusamy Murugan A. , Murugan Kadarkarai , Chang Shih-Chang , Lee Hsin-Chung , Hsu Shih-Tien , Kumar S. Suresh , Umezawa Akihiro 
Published: December 2015

AbstractThe tentative clinical application of human pluripotent stem cells (hPSCs), such as human embryonic stem cells and human induced pluripotent stem cells, is restricted by the possibility of xenogenic contamination resulting from the use of mouse embryonic fibroblasts (MEFs) as a feeder layer. Therefore, we investigated hPSC cultures on biomaterials with different elasticities that were grafted with different nanosegments. We prepared dishes coated with polyvinylalcohol-co-itaconic acid hydrogels grafted with an oligopeptide derived from vitronectin (KGGPQVTRGDVFTMP) with elasticities ranging from 10.3 to 30.4 kPa storage moduli by controlling the crosslinking time. The hPSCs cultured on the stiffest substrates (30.4 kPa) tended to differentiate after five days of culture, whereas the hPSCs cultured on the optimal elastic substrates (25 kPa) maintained their pluripotency for over 20 passages under xeno-free conditions. These results indicate that cell culture matrices with optimal elasticity can maintain the pluripotency of hPSCs in culture.
Encoding of frequency-modulation (FM) rates in human auditory cortex
Authors: Okamoto Hidehiko , Kakigi Ryusuke 
Published: December 2015

AbstractFrequency-modulated sounds play an important role in our daily social life. However, it currently remains unclear whether frequency modulation rates affect neural activity in the human auditory cortex. In the present study, using magnetoencephalography, we investigated the auditory evoked N1m and sustained field responses elicited by temporally repeated and superimposed frequency-modulated sweeps that were matched in the spectral domain, but differed in frequency modulation rates (1, 4, 16 and 64 octaves per sec). The results obtained demonstrated that the higher rate frequency-modulated sweeps elicited the smaller N1m and the larger sustained field responses. Frequency modulation rate had a significant impact on the human brain responses, thereby providing a key for disentangling a series of natural frequency-modulated sounds such as speech and music.
Direct and accurate measurement of size dependent wetting behaviors for sessile water droplets
Authors: Park Jimin , Han Hyung-Seop , Kim Yu-Chan , Ahn Jae-Pyeong , Ok Myoung-Ryul , Lee Kyung Eun , Lee Jee-Wook , Cha Pil-Ryung , Seok Hyun-Kwang , Jeon Hojeong 
Published: December 2015

AbstractThe size-dependent wettability of sessile water droplets is an important matter in wetting science. Although extensive studies have explored this problem, it has been difficult to obtain empirical data for microscale sessile droplets at a wide range of diameters because of the flaws resulting from evaporation and insufficient imaging resolution. Herein, we present the size-dependent quantitative change of wettability by directly visualizing the three phase interfaces of droplets using a cryogenic-focused ion beam milling and SEM-imaging technique. With the fundamental understanding of the formation pathway, evaporation, freezing and contact angle hysteresis for sessile droplets, microdroplets with diameters spanning more than three orders of magnitude on various metal substrates were examined. Wetting nature can gradually change from hydrophobic at the hundreds-of-microns scale to super-hydrophobic at the sub-μm scale and a nonlinear relationship between the cosine of the contact angle and contact line curvature in microscale water droplets was demonstrated. We also showed that the wettability could be further tuned in a size-dependent manner by introducing regular heterogeneities to the substrate.
Remarkably stable amorphous metal oxide grown on Zr-Cu-Be metallic glass
Authors: Lim Ka Ram , Kim Chang Eun , Yun Young Su , Kim Won Tae , Soon Aloysius , Kim Do Hyang 
Published: December 2015

AbstractIn the present study, we investigated the role of an aliovalent dopant upon stabilizing the amorphous oxide film. We added beryllium into the Zr50Cu50 metallic glass system and found that the amorphous oxide layer of Be-rich phase can be stabilized even at elevated temperature above Tg of the glass matrix. The thermal stability of the amorphous oxide layer is substantially enhanced due to Be addition. As confirmed by high-temperature cross-section HR-TEM, fully disordered Be-added amorphous layer is observed, while the rapid crystallization is observed without Be. To understand the role of Be, we employed ab-initio molecular dynamics to compare the mobility of ions with/without Be dopant and propose a disordered model where Be dopant occupies Zr vacancy and induces structural disorder to the amorphous phase. We find that the oxygen mobility is slightly suppressed due to Be dopant and Be mobility is unexpectedly lower than that of oxygen, which we attribute to the aliovalent nature of Be dopant whose diffusion always accompany multiple counter-diffusion of other ions. Here, we explain the origin of superior thermal stability of amorphous oxide film in terms of enhanced structural disorder and suppressed ionic mobility due to the aliovalent dopant.
PEGylated silica-enzyme nanoconjugates: a new frontier in large scale separation of α-amylase
Authors: Mohsen Dehnavi Seyed , Pazuki Gholamreza , Vossoughi Manouchehr 
Published: December 2015

AbstractHigh resolution is nearly lost at the expense of throughput in most conventional bioseparation methods. Nanoparticles, due to their high surface to volume ratio, are attractiveenzyme carriers, which can boost the performance of extraction manifold. Here, wereport design and application ofa method highly capable of improving the partitioning of α-amylase in aqueous two-phase system of polymer and salt. Silica nanoparticle introduced to the system acts as a bridge that connects the enzyme and polymer. Theconjugated nanoparticles form the major part of the upper phase and thus significantly enhance the protein recovery. A thorough investigation was performed on the structure of the nanoconjugatesas well as analyzing the conformational structure of the enzyme after conjugationto explore anypossible denaturation.
Applications of gradient index metamaterials in waveguides
Authors: Fu Yangyang , Xu Yadong , Chen Huanyang 
Published: December 2015

AbstractIn this letter, we find that gradient index metamaterials (GIMs) could be utilized to manipulate wave propagation in waveguides. Through manipulating the conversion between propagating wave and surface wave, we can design some interesting applications in waveguides, such as controlling transmission effect, realizing bending waveguide and achieving waveguide splitting effect. These devices not only work for both transverse electric and magnetic polarized waves, but also function for a broadband of spectra. Numerical simulations are performed to verify our findings.
Ultrafast degradation of azo dyes catalyzed by cobalt-based metallic glass
Authors: Qin X. D. , Zhu Z. W. , Liu G. , Fu H. M. , Zhang H. W. , Wang A. M. , Li H. , Zhang H. F. 
Published: December 2015

AbstractReactivity and mass loss are considered mutually exclusive in conventional zero-valent metal (ZVM) technology to treat environmental contaminants. Here, we report the outstanding performance of Co-based metallic glass (MG) in degrading an aqueous solution of azo dye, thus eliminating this trade-off. Ball-milled Co-based MG powders completely degrade Acid Orange II at an ultrafast rate. The surface-area-normalized rate constant of Co-based MG powders was one order of magnitude higher than that of Co-based crystalline counterparts and three orders of magnitude higher than that of the widely studied Fe0 powders. The coordinatively unsaturated local structure in Co-based MG responds to the catalysis for degradation, resulting in very low mass loss. Wide applicability and good reusability were also present. Co-based MG is the most efficient material for azo dye degradation reported thus far and will promote the practical application of MGs as functional materials.
Anomalous Dynamics of a Lipid Recognition Protein on a Membrane Surface
Authors: Yamamoto Eiji , Kalli Antreas C. , Akimoto Takuma , Yasuoka Kenji , Sansom Mark S. P. 
Published: December 2015

AbstractPleckstrin homology (PH) domains are lipid-binding modules present in peripheral membrane proteins which interact with phosphatidyl-inositol phosphates (PIPs) in cell membranes. We use multiscale molecular dynamics simulations to characterize the localization and anomalous dynamics of the DAPP1 PH domain on the surface of a PIP-containing lipid bilayer. Both translational and rotational diffusion of the PH domain on the lipid membrane surface exhibit transient subdiffusion, with an exponent α ≈ 0.5 for times of less than 10 ns. In addition to a PIP3 molecule at the canonical binding site of the PH domain, we observe additional PIP molecules in contact with the protein. Fluctuations in the number of PIPs associated with the PH domain exhibit 1/f noise. We suggest that the anomalous diffusion and long-term correlated interaction of the PH domain with the membrane may contribute to an enhanced probability of encounter with target complexes on cell membrane surfaces.
Condensation and dissolution of nematic droplets in dispersions of colloidal rods with thermo–sensitive depletants
Authors: Modlińska Anna , Alsayed Ahmed M. , Gibaud Thomas 
Published: December 2015

AbstractNematic droplets are droplets composed of elongated molecules that tend to point in the same direction but do not have any positional order. Such droplets are well known to adopt a spindle shape called tactoid. How such droplets condensate or melt and how the orientational symmetry is broken remains however unclear. Here we use a colloidal system composed of filamentous viruses as model rod–like colloids and pnipam microgel particles to induce thermo–sensitive depletion attraction between the rods. Microscopy experiments coupled to particle tracking reveal that the condensation of a nematic droplet is preceded by the formation of a new phase, an isotropic droplet. As the viruses constitute an excellent experimental realization of hard rods, it follows that the phenomenology we describe should be relevant to diverse micro- and nano-sized rods that interact through excluded volume interactions. This transition between isotropic and nematic droplets provides a new and reversible pathway to break the symmetry and order colloidal rods within a droplet with an external stimulus and could constitute a benchmark experiment for a variety of technologies relying on reconfigurable control of rods.
Titania modification with a ruthenium(ii) complex and gold nanoparticles for photocatalytic degradation of organic compounds
Authors: Zheng Shuaizhi , Wei Zhishun , Yoshiiri Kenta , Braumüller Markus , Ohtani Bunsho , Rau Sven , Kowalska Ewa 
Published: December 2015

Abstract
Titania of fine anatase nanoparticles (ST01) was modified successively with two components, i.e., a ruthenium(ii) complex with phosphonic anchoring groups [Ru(bpy)2(4,4′-(CH2PO3H2)2bpy)]2+ bpy = 2,2′-bipyridine (RuIICP) and gold nanoparticles (Au). Various compositions of two titania modifiers were investigated, i.e., Au, Au + RuIICP, Au + 0.5RuIICP, RuIICP, 0.5RuIICP and 0.25RuIICP, where Au and RuIICP correspond to 0.81 mol% and 0.34 mol% (with respect to titania), respectively. In the case of hybrid photocatalysts, the sequence of modification (ruthenium(ii) complex adsorption or gold deposition) was investigated to check its influence on the resultant properties and thus photocatalytic performance. Diffuse reflectance spectroscopy (DRS), X-ray photoelectron spectroscopy (XPS) and scanning transmission electron microscopy (STEM) were applied to characterize the structural properties of the prepared photocatalysts, which confirmed the successful introduction of modifiers of the ruthenium(ii) complex and/or gold NPs. Different distributions of gold particle sizes and chemical compositions were obtained for the hybrid photocatalysts prepared with an opposite sequence. It was found that photocatalytic activities depended on the range of used irradiation (UV/vis or vis) and the kind of modifier in different ways. Gold NPs improved the photocatalytic activities, while RuIICP inhibited the reactions under UV/vis irradiation, i.e., methanol dehydrogenation and acetic acid degradation. Oppositely, RuIICP greatly enhanced the photocatalytic activities for 2-propanol oxidation under visible light irradiation.
Operational experiences with inertial response provided by type 4 wind turbines
Authors: Fischer Markus , Engelken Soenke , Mihov Nikolay , Mendonca Angelo 
Published: December 2015

The need for inertial response provided by wind turbines (WTs) has been discussed in the industry for more than five years now. Yet, as of today only very few grid codes include specific requirements. Hence, the number of wind farms in commercial operation using such frequency control features is low, and knowledge of the real capabilities and limitations of inertial response from WTs is limited. The objective of this article was to summarise and to assess two years of operational experience with inertial response provided by type 4 WTs installed in a 138 MW wind farm in the Canadian province of Québec. In order to put the topic into context, existing and anticipated future grid code requirements in respect to inertial response as well as related performance criteria were summarised. Data from high‐frequency measurement devices recorded at various operating conditions and grid situations was downloaded and processed. The actual performance was compared with the expected characteristics for each of the measurements, which allowed identifying areas for further development. Results of dynamic simulations demonstrated that the methodology and the models used for frequency control studies need to be improved.
The Attentional Capacity of Visual Search under Flicker Conditions
Authors: Rensink R A 
Published: December 2015

High-level allocation of attention is required for detecting changes in images under ‘flicker’ conditions, ie when an original and a modified image are repetitively alternated, with a blank field between each display (R A Rensink, J K O'Regan, J J Clark, 1995 Perception24 Supplement, 26). But how many items can attention ‘grab’ and compare during each display? To determine this capacity, search experiments were carried out under flicker conditions, with displays formed of arrays of rectangles. In half the trials, displays differed by the position of one of the rectangles; in the other half, displays remained the same. Subjects were asked to determine if a change was occurring between the two displays. Performance was measured for several durations of displays and blank fields. In all cases, search showed a clear serial deployment of attention. Comparing the rate of this deployment against the rate of display alternation yielded the number of items compared at a time. Results indicate that, for display durations of less than 100 ms, average capacity is about 1.5 items. Capacity increases somewhat with longer display times, indicating that more items can be stored with increasing display time, or that more items are being grouped into each attentional ‘operand’.
Abrupt Transitions in the Perception of Illusory Contours Triggered by Specific Visual Stimuli
Authors: Rubin N , Grossetete A , Nakayama K , Shapley R 
Published: December 2015

Two forms of learning have been identified in previous studies. Gradual improvement is observed for many perceptual tasks; it is often stimulus-specific and is consequently thought to involve synaptic modifications in early visual cortical areas. In contrast, sudden transitions, either cognitive (‘insight’) or perceptual (eg in the Dalmatian dog picture) are generally thought to occur more centrally. Here we report that a sudden transition in the perception of illusory-contour stimuli can be triggered by specific visual stimuli, rather than by verbal instructions, leading to an abrupt improvement in psychophysical performance. Subjects discriminated between two classes of Kanizsa-like shapes where the (illusory) edges were slightly curved into ‘thin’ or ‘fat’ figures (D L Ringach, R Shapley, 1993 Perception22 Supplement, 51). In the first (‘test’) block, only small amounts of curvature (1° – 3°) were given; subjects performed poorly in that block. In the second (‘training’) block, stimuli with larger curvature (4° – 6°) were added to the set. Performance for the 1° – 3° stimuli improved abruptly—often within seconds—compared to the first block: the pooled responses of eight naive subjects showed a marked jump, followed by maintained elevation, of the fraction-correct responses as a function of time. Good performance was retained in a third (re-test) block, with a stimulus set identical to that of the first block. Control experiments verified that the subjects understood the task from the beginning. Furthermore, the learned performance did not transfer to a different (smaller) retinal size. Thus the jump in performance is a perceptual, stimulus-specific phenomenon (rather than a cognitive one), although it exhibits characteristics of ‘insightful’ understanding.
Mislocalisation of Chromatic and Achromatic Stimuli during Saccadic Eye Movements
Authors: Sato M , Uchikawa K 
Published: December 2015

It is well known that a brief flash of a small stationary target presented during saccades appears to be shifted from the actual position. The perceptual location of a visual target should be determined by the retinal information and the eye position signal. This mislocalisation seems to indicate that the change of the eye position signal is more sluggish than the actual eye movements. Delay of transmission of the retinal information may be a factor of mislocalisation. Here, we measured the perceptual location of chromatic stimuli which had different temporal characteristics from achromatic stimuli. The chromatic stimulus was a small red spot which replaced the green field for 10 ms. The green field subtended 5 deg × 24 deg and its luminance was 78.6 cd m−2. The luminance of the chromatic stimulus was adjusted to be the same as the green field by the minimum flicker method. The luminance of the achromatic stimulus was 234 cd m−2. Our results show that the chromatic and the achromatic stimuli presented at the beginning of saccades are mislocalised in the same direction as the saccades. We also found that the mislocalisation of the chromatic stimulus began slightly earlier than the achromatic stimulus. Also the chromatic stimulus presented during saccades was mislocalised in the opposite direction to the saccades whereas the achromatic stimulus was localised approximately at the actual position. These results suggest that the chromatic response is transmitted more slowly before saccades but faster during saccades than the achromatic response.
Control of Fixation Duration and Saccade Direction during Search
Authors: Hooge I T C , Erkelens C J 
Published: December 2015

To investigate the interaction between saccade preparation and foveal analysis on multi-fixation search, we designed an experiment in which the result of the foveal analysis is relevant for programming the direction of the next saccade. We examined whether fixation duration is adjusted to the duration of the analysis process or not. Subjects were asked to find a circle (diameter 2.1 deg) among 35 circles (gap size 0.3 deg, diameter 2.1 deg) that were placed on an invisible hexagonal grid (35 deg × 35 deg). Eye movements of the right eye were measured. The gaps of the circles indicated the direction in which the circle could be found. Subjects were instructed to make eye movements in the direction that was indicated by the gap of the fixated circle. The proportion of eye movements made in the indicated directions ranged from 0.54 to 0.72 (0.25 is chance level). Thus direction information is indeed, but improperly, used for the programming of eye movements. Durations of fixations preceding eye movements made in non-indicated directions were smaller than durations of fixations preceding eye movements made in indicated directions. From these results we conclude that saccade preparation only uses the result of the analysis if it is available in time and that there is no direct control of fixation duration by a mechanism that monitors the analysis process.
Colour Constancy in Goldfish—The Role of Surround Reflectance
Authors: Fritsch J , Neumeyer C 
Published: December 2015

Simultaneous colour contrast as well as colour constancy have been shown quantitatively for the goldfish. In behavioural experiments we investigated colour constancy in goldfish for green and purple colours. Two fish were trained with food rewards to select one of ten test-fields in hues ranging, in small steps of saturation, from deep green, through grey, to deep purple. In the training situation the whole disk was illuminated by white light, whereas in the test situation it was changed to green and purple light, respectively. The role of surround reflectance was investigated by presenting the test fields either on a black or on a white surround. With a black surround (low reflectance) in purple illumination the fish chose test fields that were more green than the training field indicating imperfect colour constancy. With a white surround (high reflectance), however, the fish chose testfields that were more purple. This ‘overcompensation’ indicates that a white surround induces a hue complementary to that of the illumination. A similar phenomenon is known as the Helson — Judd effect in human colour vision. For green illumination the phenomenon was similar. The effect could be decreased by reducing the white surround to small white annuli around the test fields. A decrease was also achieved by separating the white surround from the test fields by black annuli. Perfect colour constancy could thus be obtained with a certain size of a white surround as well as with a certain size of separation. We therefore assume that lateral interactions play an important role in colour constancy.