bluuebunny/crossref_metadata_2025_split huggingface dataset:
Laboratory experiments on counter-propagating collisions of solitary waves. Part 2. Flow field
Authors: Chen Yongshuai , Zhang Eugene , Yeh Harry 
Published: August 2014

AbstractIn the companion paper (Chen & Yeh, J. Fluid Mech., vol. 749, 2014, pp. 577–596), collisions of counter-propagating solitary waves were studied experimentally by analysing the measured water-surface variations. Here we study the flow fields associated with the collisions. With the resolved velocity data obtained in the laboratory, the flow fields are analysed in terms of acceleration, vorticity, and velocity-gradient tensors in addition to the velocity field. The data show that flow acceleration becomes maximum slightly before and after the collision peak, not in accord with the linear theory which predicts the maximum acceleration at the collision peak. Visualized velocity-gradient-tensor fields show that fluid parcels are stretched vertically prior to reaching the state of maximum wave amplitude. After the collision peak, fluid parcels are stretched in the horizontal direction. The boundary-layer evolution based on the vorticity generation and diffusion processes are discussed. It is shown that flow separation occurs at the bed during the collision. The collision creates small dispersive trailing waves. The formation of the trailing waves is captured by observing the transition behaviour of the velocity-gradient-tensor field: the direction of stretching of fluid parcels alternates during the generation of the trailing waves.
On the Richtmyer–Meshkov instability evolving from a deterministic multimode planar interface
Authors: Tritschler V. K. , Olson B. J. , Lele S. K. , Hickel S. , Hu X. Y. , Adams N. A. 
Published: August 2014

AbstractWe investigate the shock-induced turbulent mixing between a light and a heavy gas, where a Richtmyer–Meshkov instability (RMI) is initiated by a shock wave with Mach number $\def \xmlpi #1{}\def \mathsfbi #1{\boldsymbol {\mathsf {#1}}}\let \le =\leqslant \let \leq =\leqslant \let \ge =\geqslant \let \geq =\geqslant \def \Pr {\mathit {Pr}}\def \Fr {\mathit {Fr}}\def \Rey {\mathit {Re}}\mathit{Ma}= 1.5$. The prescribed initial conditions define a deterministic multimode interface perturbation between the gases, which can be imposed exactly for different simulation codes and resolutions to allow for quantitative comparison. Well-resolved large-eddy simulations are performed using two different and independently developed numerical methods with the objective of assessing turbulence structures, prediction uncertainties and convergence behaviour. The two numerical methods differ fundamentally with respect to the employed subgrid-scale regularisation, each representing state-of-the-art approaches to RMI. Unlike previous studies, the focus of the present investigation is to quantify the uncertainties introduced by the numerical method, as there is strong evidence that subgrid-scale regularisation and truncation errors may have a significant effect on the linear and nonlinear stages of the RMI evolution. Fourier diagnostics reveal that the larger energy-containing scales converge rapidly with increasing mesh resolution and thus are in excellent agreement for the two numerical methods. Spectra of gradient-dependent quantities, such as enstrophy and scalar dissipation rate, show stronger dependences on the small-scale flow field structures as a consequence of truncation error effects, which for one numerical method are dominantly dissipative and for the other dominantly dispersive. Additionally, the study reveals details of various stages of RMI, as the flow transitions from large-scale nonlinear entrainment to fully developed turbulent mixing. The growth rates of the mixing zone widths as obtained by the two numerical methods are ${\sim } t^{7/12}$ before re-shock and ${\sim } (t-t_0)^{2/7}$ long after re-shock. The decay rate of turbulence kinetic energy is consistently ${\sim } (t-t_0)^{-10/7}$ at late times, where the molecular mixing fraction approaches an asymptotic limit $\varTheta \approx 0.85$. The anisotropy measure $\langle a \rangle _{xyz}$ approaches an asymptotic limit of ${\approx }0.04$, implying that no full recovery of isotropy within the mixing zone is obtained, even after re-shock. Spectra of density, turbulence kinetic energy, scalar dissipation rate and enstrophy are presented and show excellent agreement for the resolved scales. The probability density function of the heavy-gas mass fraction and vorticity reveal that the light–heavy gas composition within the mixing zone is accurately predicted, whereas it is more difficult to capture the long-term behaviour of the vorticity.
Constitutional Projects for the Division of Powers in Mexico during Iturbide's Empire, 1821–1823
Authors: ANDREWS CATHERINE 
Published: August 2014

AbstractThis article examines the division of powers established in a number of constitutional projects presented during the First Mexican Empire (1821–3). The essay rejects the idea, present in much recent historiography, that constitutional debate in Mexico was exclusively shaped by the experience of Spanish government. Instead it argues that the empire's politicians drew on a wide range of theories, ideas and examples from other constitutional systems.
The future of bilingualism research: Insufferably optimistic and replete with new questions
Authors: TITONE DEBRA , BAUM SHARI 
Published: August 2014

The scientific process applied to any domain is a thing of power and beauty. It enables its practitioners to systematically and rigorously pursue questions of importance, in a manner that is, by necessity, adaptive and tenacious. As was his way with most matters of relevance to psychology, the words of William James (The Principles of Psychology, 1890) are illustrative here:
Romeo wants Juliet as the filings want the magnet; and if no obstacles intervene he moves towards her by as straight a line as they. But Romeo and Juliet, if a wall be built between them, do not remain idiotically pressing their faces against its opposite sides like the magnet and the filings with the card. Romeo soon finds a circuitous way, by scaling the wall or otherwise, of touching Juliet's lips directly. With the filings the path is fixed; whether it reaches the end depends on accidents. With the lover it is the end which is fixed, the path may be modified indefinitely. (p. 7)
Parental scaffolding as a bootstrapping mechanism for learning grasp affordances and imitation skills
Authors: Ugur Emre , Nagai Yukie , Celikkanat Hande , Oztop Erhan 
Published: August 2014

SUMMARYParental scaffolding is an important mechanism that speeds up infant sensorimotor development. Infants pay stronger attention to the features of the objects highlighted by parents, and their manipulation skills develop earlier than they would in isolation due to caregivers' support. Parents are known to make modifications in infant-directed actions, which are often called “motionese”7. The features that might be associated with motionese are amplification, repetition and simplification in caregivers' movements, which are often accompanied by increased social signalling. In this paper, we extend our previously developed affordances learning framework to enable our hand-arm robot equipped with a range camera to benefit from parental scaffolding and motionese. We first present our results on how parental scaffolding can be used to guide the robot learning and to modify its crude action execution to speed up the learning of complex skills. For this purpose, an interactive human caregiver-infant scenario was realized with our robotic setup. This setup allowed the caregiver's modification of the ongoing reach and grasp movement of the robot via physical interaction. This enabled the caregiver to make the robot grasp the target object, which in turn could be used by the robot to learn the grasping skill. In addition to this, we also show how parental scaffolding can be used in speeding up imitation learning. We present the details of our work that takes the robot beyond simple goal-level imitation, making it a better imitator with the help of motionese.
PATIENT PERSPECTIVE IN HEALTH TECHNOLOGY ASSESSMENT OF PHARMACEUTICALS IN FINLAND
Authors: Kleme Jenni , Pohjanoksa-Mäntylä Marika , Airaksinen Marja , Enlund Hannes , Kastarinen Helena , Peura Piia , Hämeen-Anttila Katri 
Published: August 2014

Objectives: The need to consider the patient perspective in health technology assessments (HTA) has been widely recognized. In July 2012, the Finnish Medicines Agency (Fimea) published a national recommendation for integrating the patient perspective into the HTAs of pharmaceuticals. The aim of this study is to describe the development of the recommendation for integrating the patient perspective into the HTA process of pharmaceuticals in Finland.Methods: The development of the recommendation was based on a review of international recommendations and experiences of patient and public involvement in HTA. The draft recommendation was tested in two focus group discussions (n = 7 patients) and three individual interviews among diabetes patients (type 1 or 2) using long-acting insulin treatment. The recommendation was open for public consultation in April 2012 and revised according to the comments received.Results: Patients will be involved in multiple stages of Fimea's HTA process. The recommendation includes step-by-step instructions on how to assess the patient perspective. The main focus is on qualitative interviews, which will be conducted at the beginning of the assessments to gain information, particularly on patient preferences and values, including positive and negative outcomes important to patients and ethical and social aspects of the medicine's use.Conclusions: The recommendation will act as a tool to integrate patients’ experiences, needs and preferences into Fimea's HTAs of pharmaceuticals.
Chromatic induction from surrounding stimuli under perceptual suppression
Authors: HORIUCHI KOJI , KURIKI ICHIRO , TOKUNAGA RUMI , MATSUMIYA KAZUMICHI , SHIOIRI SATOSHI 
Published: August 2014

AbstractThe appearance of colors can be affected by their spatiotemporal context. The shift in color appearance according to the surrounding colors is called color induction or chromatic induction; in particular, the shift in opponent color of the surround is called chromatic contrast. To investigate whether chromatic induction occurs even when the chromatic surround is imperceptible, we measured chromatic induction during interocular suppression. A multicolor or uniform color field was presented as the surround stimulus, and a colored continuous flash suppression (CFS) stimulus was presented to the dominant eye of each subject. The subjects were asked to report the appearance of the test field only when the stationary surround stimulus is invisible by interocular suppression with CFS. The resulting shifts in color appearance due to chromatic induction were significant even under the conditions of interocular suppression for all surround stimuli. The magnitude of chromatic induction differed with the surround conditions, and this difference was preserved regardless of the viewing conditions. The chromatic induction effect was reduced by CFS, in proportion to the magnitude of chromatic induction under natural (i.e., no-CFS) viewing conditions. According to an analysis with linear model fitting, we revealed the presence of at least two kinds of subprocesses for chromatic induction that reside at higher and lower levels than the site of interocular suppression. One mechanism yields different degrees of chromatic induction based on the complexity of the surround, which is unaffected by interocular suppression, while the other mechanism changes its output with interocular suppression acting as a gain control. Our results imply that the total chromatic induction effect is achieved via a linear summation of outputs from mechanisms that reside at different levels of visual processing.
Molecular characterisation of haemoparasites in forest birds from Robinson Crusoe Island: Is the Austral Thrush a potential threat to endemic birds?
Authors: MARTÍNEZ JAVIER , VÁSQUEZ RODRIGO A. , VENEGAS CRISTOBAL , MERINO SANTIAGO 
Published: August 2014

SummaryThe Juan Fernández FirecrownSephanoides fernandensisand Juan Fernández Tit-TyrantAnairetes fernandezianusare two endemic forest birds inhabiting Robinson Crusoe Island and are classified as ‘Critically Endangered’ and ‘Near Threatened’ respectively by IUCN. Previous research concluded that the two main factors involved in the decline of these birds were habitat degradation and the introduction of predator / competitor species. However, the potential role of parasitic diseases has not yet been explored. In order to explore hypothetical host-switching phenomena, we genetically identified the haemoparasites present in four bird species, the two endemic species mentioned above and two recent colonisers, Green-Backed FirecrownSephanoides sephaniodesand Austral ThrushTurdus falcklandii. We failed to find infections by different blood parasites (Plasmodium,Haemoproteus,Leucocytozoon,Trypanosoma,BabesiaandIsospora) in the endangered Juan Fernández Firecrown. However, the Juan Fernández Tit-Tyrant was infected with some parasites shared with the Austral Thrush. The latter species may function as a key-host species on the island as it showed both the higher hemoparaasitic diversity and prevalence. The role of Green-Backed Firecrowns is apparently of lower importance because only one individual was found parasitized. The Austral Thrush could be responsible of the introduction of some parasites also isolated from the Juan Fernández Tit-Tyrant and represent a potential threat to the endemic firecrown due to its role as a reservoir. The spread of Austral Thrushes could increase the contact between species, increasing the probability of a switching event.
Searching for Earth-mass planets around α Centauri: precise radial velocities from contaminated spectra
Authors: Bergmann Christoph , Endl Michael , Hearnshaw John B. , Wittenmyer Robert A. , Wright Duncan J. 
Published: August 2014

AbstractThis work is part of an ongoing project which aims to detect terrestrial planets in our neighbouring star system α Centauri using the Doppler method. Owing to the small angular separation between the two components of the α Cen AB binary system, the observations will to some extent be contaminated with light coming from the other star. We are accurately determining the amount of contamination for every observation by measuring the relative strengths of the H-α and NaD lines. Furthermore, we have developed a modified version of a well-established Doppler code that is modelling the observations using two stellar templates simultaneously. With this method we can significantly reduce the scatter of the radial velocity (RV) measurements due to spectral cross-contamination and hence increase our chances of detecting the tiny signature caused by potential Earth-mass planets. After correcting for the contamination we achieve RV precision of ~2.5 m s−1 for a given night of observations. We have also applied this new Doppler code to four southern double-lined spectroscopic binary systems (HR159, HR913, HR7578 and HD181958) and have successfully recovered radial velocities for both components simultaneously.
Trithorax complex component Menin controls differentiation and maintenance of T helper 17 cells
Authors: Watanabe Yukiko , Onodera Atsushi , Kanai Urara , Ichikawa Tomomi , Obata-Ninomiya Kazushige , Wada Tomoko , Kiuchi Masahiro , Iwamura Chiaki , Tumes Damon J. , Shinoda Kenta , Yagi Ryoji , Motohashi Shinichiro , Hirahara Kiyoshi , Nakayama Toshinori 
Published: August 2014

SignificanceEpigenetic modifications, including various histone modifications, play important roles in regulating gene expression. The Trithorax group (TrxG) complex induces permissive histone modifications to activate transcription. We herein investigate the role for Menin, a component of the TrxG complex, in T helper (Th) cell differentiation, and find a critical role for Menin in differentiation and maintenance of Th17 cells. Menin is required for Th17 cell differentiation in vitro through the direct regulation ofIl17aexpression. Menin controls IL-17–mediated pathology in vivo. Menin is also required to maintain expression ofRorc, the gene encoding RORγt, a key transcription factor for Th17 cell function. Thus, Menin orchestrates Th17 cell differentiation and function by regulating both induction and maintenance of target gene expression.
Submesoscale dispersion in the vicinity of the
Deepwater Horizon
spill
Authors: Poje Andrew C. , Özgökmen Tamay M. , Lipphardt Bruce L. , Haus Brian K. , Ryan Edward H. , Haza Angelique C. , Jacobs Gregg A. , Reniers A. J. H. M. , Olascoaga Maria Josefina , Novelli Guillaume , Griffa Annalisa , Beron-Vera Francisco J. , Chen Shuyi S. , Coelho Emanuel , Hogan Patrick J. , Kirwan Albert D. , Huntley Helga S. , Mariano Arthur J. 
Published: August 2014

Significance
We report here on results obtained from the largest upper-ocean dispersion field program conducted to date. The observations provided, for the first time to our knowledge, an accurate and nearly simultaneous description of the ocean surface velocity field on spatial scales ranging from 100 m to 100 km. We show conclusively that ocean flows contain significant energy at scales below 10 km and that their fluctuations dictate the initial spread of tracer/pollutant clouds. Neither state-of-the art operational models nor satellite altimeters capture the flows needed for accurately estimating the dispersion of surface particles.
Direct measurement of the dielectric polarization properties of DNA
Authors: Cuervo Ana , Dans Pablo D. , Carrascosa José L. , Orozco Modesto , Gomila Gabriel , Fumagalli Laura 
Published: August 2014

Significance
The strength of DNA–DNA and DNA–ligand electrostatic interactions crucially depends on the electric polarizability of DNA, represented by its dielectric constant. This has remained unknown owing to the lack of experimental techniques able to measure it. Here, we experimentally determined the dielectric constant of double-stranded DNA in a native condensed state inside a single bacteriophage as well as the dielectric constants of the protein shell and tail that compose the viral capsid using scanning force microscopy. We supported the experimental data by theoretically determining the DNA dielectric constant using atomistic simulations. Both approaches yield a dielectric constant of DNA around 8, sensibly higher than commonly assumed, thus revealing a DNA intrinsic property essential for realistic computational description of DNA.
Endothelial Akt1 mediates angiogenesis by phosphorylating multiple angiogenic substrates
Authors: Lee Monica Y. , Luciano Amelia K. , Ackah Eric , Rodriguez-Vita Juan , Bancroft Tara A. , Eichmann Anne , Simons Michael , Kyriakides Themis R. , Morales-Ruiz Manuel , Sessa William C. 
Published: August 2014

Significance
The expression of multiple isoforms of a protein kinase in cells raises the question of which substrates are preferentially phosphorylated by each isoform. Endothelial cells (ECs) that line all blood vessels express the protein kinases, Akt1 and Akt2, and we demonstrate here that endothelial nitric oxide synthase (eNOS) is a preferential Akt1 substrate and supraphysiological overexpression of Akt2 is needed to phosphorylate eNOS and promote NO release. In mice, the endothelial loss of Akt1, but not Akt2, retards vessel growth, and quantitative assessment of the phosphoproteomes in ECs isolated from these mice shows that Akt1 uniquely phosphorylates several important proteins regulating vascular function. Thus, despite the presence of both isoforms of Akt in the endothelium, substrate phosphorylation by Akt1 is nonredundant.
IL-6/STAT3 promotes regeneration of airway ciliated cells from basal stem cells
Authors: Tadokoro Tomomi , Wang Yang , Barak Larry S. , Bai Yushi , Randell Scott H. , Hogan Brigid L. M. 
Published: August 2014

Significance
The airways of the lungs are lined by ciliated and secretory epithelial cells important for mucociliary clearance. When these cells are damaged or lost, they are replaced by the differentiation of basal stem cells. Little is known about how this repair is orchestrated by signaling pathways in the epithelium and underlying stroma. We present evidence using cultured airway cells and genetic manipulation of a mouse model of airway repair that the cytokine IL-6 promotes the differentiation of ciliated vs. secretory cells. This process involves direct Stat3 regulation of genes controlling both cell fate (Notch1) and the differentiation of multiciliated cells (Multicilin and forkhead box protein J1). Moreover, the major producer of IL-6 appears to be mesenchymal cells in the stroma rather than immune cells.
Fluvial network organization imprints on microbial co-occurrence networks
Authors: Widder Stefanie , Besemer Katharina , Singer Gabriel A. , Ceola Serena , Bertuzzo Enrico , Quince Christopher , Sloan William T. , Rinaldo Andrea , Battin Tom J. 
Published: August 2014

SignificanceMicrobial communities orchestrate most biogeochemical processes on Earth. In streams and rivers, surface-attached and matrix-enclosed biofilms dominate microbial life. Despite the relevance of these biofilms for ecosystem processes (e.g., metabolism and nutrient cycling), it remains unclear how features inherent to stream and river networks affect the fundamental organization of biofilm communities in these ecosystems. We combined co-occurrence analyses of biofilms based on next-generation sequencing with a probabilistic hydrological model, and showed how fragementation of microbial co-occurrence networks change across stream networks. Our analyses offer potential insights into the response of microbial community organization and persistence to human pressures that increasingly change the hydrological regime and biodiversity dynamics in fluvial networks.
Test–retest reliability of second lactate turnpoint using two different criteria in competitive cyclists
Authors: Hoefelmann Camila Peter , Diefenthaeler Fernando , Costa Vitor Pereira , de Lucas Ricardo Dantas , Shambrook Philip , Guglielmo Luiz Guilherme Antonacci 
Published: August 2014

AbstractThe aim of this study was to determine the relative and absolute reliability of second lactate turnpoint using fixed and individual blood lactate method in competitive cyclists. Twenty‐eight male, well‐trained cyclists (30.2 ± 10.1 years, 72.0 ± 7.4 kg, 177.3 ± 4.7 cm) were recruited to participate in this study. Cyclists completed two incremental cycling tests to exhaustion over a period of 7 days to determine their peak power output, maximal oxygen uptake, maximal heart rate, maximal blood lactate concentration and two lactate turnpoint criteria. The fixed blood concentration criterion (3.5 mM) and an individual criterion were assessed by a lactate‐power curve, considering power output, heart rate and oxygen uptake. The main finding of this study was that both lactate turnpoint criteria showed identical low within‐subject variation for power output (2.8% coefficient of variation). High values for test–retest correlations ranging from r = 0.70 to r = 0.94 were found for all variables in both threshold criteria. In conclusion, the individual and fixed method to determine the second lactate turnpoint showed similar high absolute and relative reliability in competitive cyclists.