bluuebunny/crossref_metadata_2025 huggingface dataset:
Shear thinning behavior of linear polymer melts under shear flow via nonequilibrium molecular dynamics
Authors: Xu Xiaolei , Chen Jizhong , An Lijia
Published: May 2014

The properties of both untangled and entangled linear polymer melts under shear flow are studied by nonequilibrium molecular dynamics simulations. The results reveal that the dependence of shear viscosity η on shear rate \documentclass[12pt]{minimal}\begin{document}$\dot{\gamma }$\end{document}γ̇, expressed by \documentclass[12pt]{minimal}\begin{document}$\eta \sim \dot{\gamma }^{-n}$\end{document}η∼γ̇−n, exhibits three distinct regimes. The first is the well-known Newtonian regime, namely, η independent of shear rate at small shear rates \documentclass[12pt]{minimal}\begin{document}$\dot{\gamma }<\tau _{0}^{-1}$\end{document}γ̇<τ0−1 (where τ0 is the longest polymer relaxation time at equilibrium). In the non-Newtonian regime (\documentclass[12pt]{minimal}\begin{document}$\dot{\gamma }>\tau _{0}^{-1}$\end{document}γ̇>τ0−1), the shear dependence of viscosity exhibits a crossover at a critical shear rate \documentclass[12pt]{minimal}\begin{document}$\dot{\gamma }_{\mathrm{c}}$\end{document}γ̇c dividing this regime into two different regimes, shear thinning regime I (ST-I) and II (ST-II), respectively. In the ST-I regime (\documentclass[12pt]{minimal}\begin{document}$\tau ^{-1}_0<\dot{\gamma }<\dot{\gamma }_{\mathrm{c}}$\end{document}τ0−1<γ̇<γ̇c), the exponent n increases with increasing chain length N, while in the ST-II regime (\documentclass[12pt]{minimal}\begin{document}$\dot{\gamma }>\dot{\gamma }_{\mathrm{c}}$\end{document}γ̇>γ̇c) a universal power law \documentclass[12pt]{minimal}\begin{document}$\eta \sim \dot{\gamma }^{-0.37}$\end{document}η∼γ̇−0.37 is found for considered chain lengths. Furthermore, the longer the polymer chain is, the smaller the shear viscosity for a given shear rate in the ST-II regime. The simulation also shows that a characteristic chain length, below which \documentclass[12pt]{minimal}\begin{document}$\dot{\gamma }_{\mathrm{c}}$\end{document}γ̇c will be equal to \documentclass[12pt]{minimal}\begin{document}$\tau _{0}^{-1}$\end{document}τ0−1, lies in the interval 30 < N < 50. For all considered chain lengths in the ST-II regime, we also find that the first and second normal stress differences N1 and N2 follow power laws of \documentclass[12pt]{minimal}\begin{document}$N_{1} \sim \dot{\gamma }^{2/3}$\end{document}N1∼γ̇2/3 and \documentclass[12pt]{minimal}\begin{document}$N_{2} \sim \dot{\gamma }^{0.82}$\end{document}N2∼γ̇0.82, respectively; the orientation resistance parameter mG follows the relation \documentclass[12pt]{minimal}\begin{document}$m_{\mathrm{G}} \sim \dot{\gamma }^{0.75}$\end{document}mG∼γ̇0.75 and the tumbling frequency ftb follows \documentclass[12pt]{minimal}\begin{document}$f_{\mathrm{tb}} \sim \dot{\gamma }^{0.75}$\end{document}f tb ∼γ̇0.75. These results imply that the effects of entanglement on the shear dependences of these properties may be negligible in the ST-II regime. These findings may shed some light on the nature of shear thinning in flexible linear polymer melts.
Compressible generalized hybrid Monte Carlo
Authors: Fang Youhan , Sanz-Serna J. M. , Skeel Robert D.
Published: May 2014

One of the most demanding calculations is to generate random samples from a specified probability distribution (usually with an unknown normalizing prefactor) in a high-dimensional configuration space. One often has to resort to using a Markov chain Monte Carlo method, which converges only in the limit to the prescribed distribution. Such methods typically inch through configuration space step by step, with acceptance of a step based on a Metropolis(-Hastings) criterion. An acceptance rate of 100% is possible in principle by embedding configuration space in a higher dimensional phase space and using ordinary differential equations. In practice, numerical integrators must be used, lowering the acceptance rate. This is the essence of hybrid Monte Carlo methods. Presented is a general framework for constructing such methods under relaxed conditions: the only geometric property needed is (weakened) reversibility; volume preservation is not needed. The possibilities are illustrated by deriving a couple of explicit hybrid Monte Carlo methods, one based on barrier-lowering variable-metric dynamics and another based on isokinetic dynamics.
Nonexistence of the usual scattering states for the generalized Ostrovsky-Hunter equation
Authors: Hayashi Nakao , Naumkin Pavel I. , Niizato Tomoyuki
Published: May 2014

We consider the Cauchy problem for the generalized Ostrovsky-Hunter equation utx = u + (|u|ρ−1u)xx. We prove the nonexistence of the usual scattering states.
Stochastic dynamics of a delayed bistable system with multiplicative noise
Authors: Dung Nguyen Tien
Published: May 2014

In this paper we investigate the properties of a delayed bistable system under the effect of multiplicative noise. We first prove the existence and uniqueness of the positive solution and show that its moments are uniformly bounded. Then, we study stochastic dynamics of the solution in long time, the lower and upper bounds for the paths and an estimate for the average value are provided.
On the mechanism of operation of a cathode spot cell in a vacuum arc
Authors: Mesyats G. A. , Bochkarev M. B. , Petrov A. A. , Barengolts S. A.
Published: May 2014

The erosive structures formed on a tungsten cathode as a result of the motion of the cathode spot of a vacuum arc over the cathode surface have been examined. It has been found that the average mass of a cathode microprotrusion having the shape of a solidified jet is approximately equal to the mass of ions removed from the cathode within the lifetime of a cathode spot cell carrying a current of several amperes. The time of formation of a new liquid-metal jet under the action of the reactive force of the plasma ejected by the cathode spot is about 10 ns, which is comparable to the lifetime of a cell. The growth rate of a liquid-metal jet is ∼104 cm/s. The geometric shape and size of a solidified jet are such that a new explosive emission center (spot cell) can be initiated within several nanoseconds during the interaction of the jet with the dense cathode plasma. This is the underlying mechanism of the self-sustained operation of a vacuum arc.
Implications of diurnal and seasonal variations in renewable energy generation for large scale energy storage
Authors: Mulder F. M.
Published: May 2014

Large scale implementation of solar and wind powered renewable electricity generation will use up to continent sized connected electricity grids built to distribute the locally fluctuating power. Systematic power output variation will then become manifest since solar power has an evident diurnal period, but also surface winds—which are driven by surface temperatures—follow a diurnal periodic behavior lagging about 4 h in time. On an ordinary day a strong diurnal varying renewable electricity generation results when combining wind and solar power on such continent sized grid. Comparison with possible demand patterns indicates that coping with such systematically varying generation will require large scale renewable energy storage and conversion for timescales and storage capacities of at least up to half a day. Seasonal timescales for versatile, high quality, generally applicable, energy conversion and storage are equally essential since the continent wide insolation varies a factor ∼3, e.g., in Europe and Northern Africa together. A first order model for estimating required energy storage and conversion magnitudes is presented, taking into account potential diurnal and seasonal energy demand and generation patterns. A few scalable energy storage methods are briefly indicated.
Surface area and porosity in obliquely grown photocatalytic titanium dioxide for air purification
Authors: Riley Michael , Wu Viola , Liu Shizhao , Gill William , Lu Toh-Ming , Plawsky Joel
Published: May 2014

Process parameters affecting the photocatalytic performance of thin films of titanium dioxide were investigated. Nanorods of titanium dioxide were grown using the technique of oblique angle deposition to create porous films of high surface area. The surface area of the films was measured as a function of deposition angle using krypton gas adsorption and compared with the photocatalytic activity of the films. The maximum surface area achieved was 148 m2/g for films deposited at a 70° angle. A gas chamber outfitted with a volatile organic compound sensor was constructed to monitor the breakdown of isobutylene test gas. The reaction rate, normalized by the film thickness, increased with measured surface area, as expected. Annealing the deposited films was required for best performance, and annealing times of only 3 min were sufficient to maximize the reaction rate, with longer times resulting in a decrease in activity. The annealing environment was not a factor. Nitrogen worked as well as oxygen. The films were found to be oxygen rich at their immediate surface but oxygen deficient in their interior regardless of annealing environment. On a per mass basis, the nanorod film outperformed standard TiO2 nanoparticle films.
Semiconducting properties of amorphous GaZnSnO thin film based on combinatorial electronic structures
Authors: Kim B. K. , Park J. S. , Kim D. H. , Chung K. B.
Published: May 2014

Semiconducting properties and electronic structures of amorphous GaZnSnO (GZTO) thin films are investigated with respect to metal cationic composition. An increase of the cationic Sn ratio resulted in an increase of the carrier concentration and a decrease of the mobility of the films. Combinatorial analysis revealed that the electrical characteristics of GZTO films are strongly correlated to changes in electronic structure. The increase in carrier concentration is related to the generation of vacancies by the changes of oxygen coordination around the cationic metal and the shallow band edge state below the conduction band. On the other hand, the decrease of mobility can be explained by the deep band edge state, and the difference between the experimental conduction band and simulated conduction band by the combinatorial electronic structure based on the chemical composition.
Observation of Brillouin gain spectrum in tapered polymer optical fiber
Authors: Hayashi Neisei , Fukuda Hideyuki , Mizuno Yosuke , Nakamura Kentaro
Published: May 2014

We report on the first observation of the Brillouin gain spectrum in a perfluorinated graded-index polymer optical fiber (POF) tapered by a heat-and-pull technique. The Stokes power was slightly enhanced by tapering probably on account of higher optical power density in the core. In addition, the Brillouin frequency shift was decreased by ∼40 MHz, which was experimentally verified to be partially caused by high heating temperature applied to the POF during the taper fabrication process. We anticipate that our findings will provide a basic principle of temperature sensing with “memory” function.
A note on the relationship between turbulent coherent structures and phase correlation
Authors: Kang Yanfei , Belušić Danijel , Smith-Miles Kate
Published: May 2014

Various definitions of coherent structures exist in turbulence research, but a common assumption is that coherent structures have correlated spectral phases. As a result, randomization of phases is believed, generally, to remove coherent structures from the measured data. Here, we reexamine these assumptions using atmospheric turbulence measurements. Small-scale coherent structures are detected in the usual way using the wavelet transform. A considerable percentage of the detected structures are not phase correlated, although some of them are clearly organized in space and time. At larger scales, structures have even higher degree of spatiotemporal coherence but are also associated with weak phase correlation. A series of specific examples are shown to demonstrate this. These results warn about the vague terminology and assumptions around coherent structures, particularly for complex real-world turbulence.
Method to analyze the ability of bulk heterojunctions of organic and hybrid solar cells to dissociate photogenerated excitons and collect free carriers
Authors: Basta M. , Dusza M. , Palewicz M. , Nawrot U. , Granek F.
Published: May 2014

We have developed a model to predict and analyze the photocurrent generation and resulting charge carrier Dissociation and Collection Efficiency (DCE) through reflectivity and quantum efficiency spectra. The DCE is regarded as a function of the morphology and exciton transport properties of the bulk heterojunction and is therefore a way to investigate the final properties of photoactive layer in a solar cell. Method proposed allows determination of the efficiency at which photogenerated excitons are dissociated in a working device with respect to the position in the cell at which the generation occurs. The method is tested on our results as well as on a number of results already present in the literature.
Tailoring conductive filaments by electroforming polarity in memristive based TiO2 junctions
Authors: Ghenzi N. , Sánchez M. J. , Rubi D. , Rozenberg M. J. , Urdaniz C. , Weissman M. , Levy P.
Published: May 2014

We probe the resistive switching response of Au/TiO2/Cu junctions, on samples initialized using both polarities electroforming. A conductive path is formed in both cases: a copper metallic filament for negative electroforming and a titanium dioxide possibly Magneli phase based filament for the positive case. We measured the resistance response of formed samples and studied their remanent resistance states. Bi (tri) stable resistance states were obtained for negative (positive) electroformed samples. The temperature dependence of the resistance discloses the underlying different nature of the associated filaments. In addition, we performed ab initio calculations to estimate the observed electroforming threshold voltages.
Drawing Skill is Related to the Efficiency of Encoding Object Structure
Authors: Perdreau Florian , Cavanagh Patrick
Published: May 2014

Accurate drawing calls on many skills beyond simple motor coordination. A good internal representation of the target object's structure is necessary to capture its proportion and shape in the drawing. Here, we assess two aspects of the perception of object structure and relate them to participants' drawing accuracy. First, we assessed drawing accuracy by computing the geometrical dissimilarity of their drawing to the target object. We then used two tasks to evaluate the efficiency of encoding object structure. First, to examine the rate of temporal encoding, we varied presentation duration of a possible versus impossible test object in the fovea using two different test sizes (8° and 28°). More skilled participants were faster at encoding an object's structure, but this difference was not affected by image size. A control experiment showed that participants skilled in drawing did not have a general advantage that might have explained their faster processing for object structure. Second, to measure the critical image size for accurate classification in the periphery, we varied image size with possible versus impossible object tests centered at two different eccentricities (3° and 8°). More skilled participants were able to categorise object structure at smaller sizes, and this advantage did not change with eccentricity. A control experiment showed that the result could not be attributed to differences in visual acuity, leaving attentional resolution as a possible explanation. Overall, we conclude that drawing accuracy is related to faster encoding of object structure and better access to crowded details.
Root traits and cellular level tolerance hold the key in maintaining higher spikelet fertility of rice under water limited conditions
Authors: Raju Bheemanahalli R. , Narayanaswamy Beerasandra R. , Mohankumar Malagondanahalli V. , Sumanth Kambalimath K. , Rajanna Mavinahalli P. , Mohanraju Basavaiah , Udayakumar Makarla , Sheshshayee Madavalam S.
Published: May 2014

Reduced spikelet fertility appears to be one of the major factors responsible for the decreased rice grain yield when cultivated under semi irrigated aerobic condition. We demonstrate that genotypes with better root systems coupled with higher cellular level tolerance (CLT) can significantly improve spikelet fertility under semi-irrigated aerobic condition in the field. A set of 20 contrasting rice accessions differing in root traits and CLT with significant molecular diversity were subjected to specific soil moisture regimes during a period between five days before and 10 days after anthesis. Lowest spikelet fertility was observed among the plants grown under water limited (WL) conditions followed by the plants grown aerobically in field conditions (AF). Deep rooted genotypes generally maintained higher spikelet fertility under both WL and AF conditions. Furthermore, genotypes that had high roots biomass as well as high CLT recorded the lowest reduction in spikelet fertility under WL and AF compared with the low root and low CLT genotype. This study emphasised the relevance of combining water acquisition and CLT for improving field level tolerance of rice to water limitation. Such genotypes recorded significantly higher grain yield under stress as well as well watered conditions. The study led to the identification of promising trait donor genotypes which can be exploited in breeding to develop superior trait pyramided cultivars suitable for semi irrigated aerobic cultivation.
Lysogenic infection in sub-tropical freshwater cyanobacteria cultures and natural blooms
Authors: Steenhauer Lisa M. , Pollard Peter C. , Brussaard Corina P. D. , Säwström Christin
Published: May 2014

Lysogeny has been reported for a few freshwater cyanobacteria cultures, but it is unknown how prevalent it is in freshwater cyanobacteria in situ. Here we tested for lysogeny in (a) cultures of eight Australian species of subtropical freshwater cyanobacteria; (b) seven strains of one species: Cylindrospermopsis raciborskii; and (c) six cyanobacterial blooms in drinking water reservoirs in South East Queensland, Australia. Lysogenic infection in the cyanobacteria was induced through mitomycin C addition. By measuring the decline in host cell numbers and the concomitant increase in cyanophages over the course of the experiment, we observed lysogenic infection in five of the eight species of cyanobacteria (i.e. Nodularia spumigena, Anabaena circinalis, Anabaenopsis arnoldii, Aphanizomenon ovalisporum, Microcystis botrys, Microcystis aeruginosa, C. raciborskii and Anabaena spp., and in four of the seven strains of C. raciborskii) but only in two of the six natural cyanobacteria blooms. Lysogeny dominated laboratory culture strains whereas in natural blooms of cyanobacteria few species were lysogenic (i.e. not mitomycin C inducible). Thus, lysogenic laboratory cultures may not necessarily reflect the genetics nor the physiology of a natural cyanobacterial population, and more information on both forms is needed to understand better how cyanobacteria behave and exist in their natural habitat.
Investigating lethal and sublethal effects of the trace metals cadmium, cobalt, lead, nickel and zinc on the anemone Aiptasia pulchella, a cnidarian representative for ecotoxicology in tropical marine environments
Authors: Howe Pelli L. , Reichelt-Brushett Amanda J. , Clark Malcolm W.
Published: May 2014

The zooxanthellate sea anemone Aiptasia pulchella is found throughout the tropical and subtropical oceans of the Indo-Pacific and is easily maintained in aquaria, posing potential suitability as a standard tropical marine test organism for use in ecotoxicology. To gain an understanding of the sensitivity of A. pulchella to trace metals, 96-h static-renewal toxicity tests were conducted. Values of 96-h LC50 between 946 and 1196 µg L–1 were estimated for cadmium, between 595 and 1146 µg L–1 for zinc, 8060 and 12 352 µg L–1 for lead and 2209 and 5751 µg L–1 for nickel. In addition, preliminary assessment of rapid tentacle retraction was made. Six-hour EC50 values of 355 and 979 µg L–1 for cadmium, between 384 and 493 µg L–1 for zinc, between 2340 and 2584 µg L–1 for nickel, and 2610 µg L–1 for lead, were estimated for ‘severe’ tentacle retraction. Cobalt concentrations up to 1547 µg L–1 caused extreme zooxanthellae loss, but no more than 10% mortality and no rapid ‘severe’ tentacle retraction. The present study has provided important baseline information, enabling comparison of the acute sensitivity of A. pulchella to trace metals with other marine invertebrates, and guiding the development of sublethal endpoints.
Estimates of abundance and apparent survival of coastal dolphins in Port Essington harbour, Northern Territory, Australia
Authors: Palmer Carol , Brooks Lyndon , Parra Guido J. , Rogers Tracey , Glasgow Debra , Woinarski John C. Z.
Published: May 2014

Context Three dolphin species occur in coastal waters of monsoonal northern Australia: the Australian snubfin (Orcaella heinsohni), humpback (Sousa sp.) and the bottlenose (Tursiops sp.). Their overall population size and trends are poorly known, and their conservation status has been difficult to resolve, but can be expected to deteriorate with likely increased development pressures. Aims We sought to provide an estimate of abundance, and apparent survival, of the three dolphin species at the largely undeveloped harbour of Port Essington (325 km2), Northern Territory, with repeated sampling over a 2.9-year period. Given increasing obligations to undertake population assessments for impact studies at proposed development sites, we assess the strengths and limitations of a systematic sampling program. Methods We used photo-identification data collected during systematic boat-based transect surveys undertaken from 2008 to 2010 and Pollock’s robust capture–recapture design model. Key results Total abundance estimates for the three species were variable across different sampling periods. The estimated number of individuals in the sampled area varied per sampling episode from 136 (s.e. 62) to 222 (s.e. 48) for snubfin, from 48 (s.e. 7) to 207 (s.e. 14) for humpbacks and from 34 (s.e. 6) to 75 (s.e. 9) for bottlenose dolphins. Apparent survival was estimated for snubfin at 0.81 (s.e. 0.11), humpbacks at 0.59 (s.e. 0.12) and bottlenose at 0.51 (s.e. 0.17) per annum. Key conclusions (1) The values derived here provide some of the only estimates of local population size for these species across monsoonal northern Australia; (2) population-size estimates varied considerably among seasons or sampling episodes; (3) the low apparent survival probabilities indicated that many individuals may move at scales larger than the study area; (4) density of snubfin and humpback dolphins in the present study area exceeded the few other estimates available for these species elsewhere in Australia. Implications The present study provided the first baseline estimates of abundance and apparent survival for three coastal dolphin species in monsoonal northern Australia. Such information is becoming increasingly important as development pressures intensify in coastal areas. Sampling protocols for future monitoring and impact assessment need an enhanced consideration of seasonality and scale issues.
Leucophores are similar to xanthophores in their specification and differentiation processes in medaka
Authors: Kimura Tetsuaki , Nagao Yusuke , Hashimoto Hisashi , Yamamoto-Shiraishi Yo-ichi , Yamamoto Shiori , Yabe Taijiro , Takada Shinji , Kinoshita Masato , Kuroiwa Atsushi , Naruse Kiyoshi
Published: May 2014

Significance

Body color plays an important role in the diversity and speciation of vertebrates. In this paper, we revealed that three loci in medaka,
leucophore free
(
lf
),
lf-2
, and
white leucophore
, which affect leucophores and xanthophores, encoded solute carrier family 2, member 15b (
slc2a15b
), paired box gene 7a (
pax7a
), and solute carrier family 2 facilitated glucose transporter, member 11b (
slc2a11b
), respectively. The
pax7
is important transcriptional factor for xanthophore development in zebrafish. The function of the two solute carrier family (
SLC
) genes was unknown. We show that the presence of the
SLCs
was coupled with the presence of xanthophores in vertebrates. The results suggest that leucophores are similar to xanthophores in their specification and differentiation process, and
SLCs
contribute to the diversification of hues in the pigment cells in vertebrates.
Public argument in the new media ecology
Authors: Harsin Jayson
Published: May 2014

This article argues that argumentation studies need to engage contemporary theories of new media technologies and culture in order to understand how public argument is empirically embedded. The article discusses the new media ecology with regard to contemporary scholarship and theory around digital cultural subjectivity and cognition, affect, professional political communication, information overload, diffusion, cybernetics and biopower — all arguably essential to understanding public argument today. It then demonstrates one way of studying popular forms of public argument by analyzing rumor bombs. Finally, it proposes that contemporary public argument has a new spatiality and temporality and is thus fundamentally different that what was considered public argument in pre-Web 2.0 culture.
Yellow Rain
Authors: Eckstein Justin
Published: May 2014

The critically acclaimed WNYC program Radiolab found itself embroiled in a controversy for its recent podcast segment “Yellow Rain.” The intent of the segment was to indict the Reagan administration’s dubious pretenses for labeling yellow rain a chemical weapon. But Radiolab’s interview with survivor and historian Eng Yang took a harsh turn and concluded with one of Radiolab’s hosts, Robert Krulwich calling Yang’s experience hearsay. This essay uses the “Yellow Rain” controversy to highlight two important features of argumentation in the podcast context. First, podcasts feature what I call ‘the acoustics of strategic maneuvering,’ which describes the way sound itself acts as presentational force in the service of a standpoint. Second, podcasts ephemerality enables Radiolab to revise their arguments to incorporate audience expectations.
The U.S.Congressional Recordas a technology of representation
Authors: Keremidchieva Zornitsa
Published: May 2014

Focusing on the historical controversies surrounding the development of the print records of the U.S. congressional debates, this essay explores how human, technological, and discursive agencies come together to constitute institutional argumentative practice. Examining the U.S.Congressional Recordthrough the lens of Bruno Latour’s concept ofdingpolitikreveals that as a technology of representation print records work less as mediators and more as agents of institutional contextualization. Print records do more than translate arguments from oral to written form or transfer arguments from the public sphere to the state. Rather, they assemble the disparate elements that constitute the terrains of governance, the character of political issues, and the norms of congressional deliberation. Hence, the material dynamics of congressional deliberation prompt not only a reconsideration of what and who is being represented by Congress, but also a methodological reorientation from normative to constitutive perspectives on institutional argumentation.
What about Translation? Beyond “Persianization” as the Language Policy in Iran
Authors: Haddadian-Moghaddam Esmaeil , Meylaerts Reine
Published: May 2014

Against the background of language policy research on Iran, and drawing on insights from recent scholarship on the role of translation in language policy, this article calls into question the claim that “Persianization” of non-Persian peoples is the main element of language policy in Iran. In so doing, the article examines closely the role of translation as enacted in two legal instruments: the Constitution of the Islamic Republic of Iran and the Law of Parliamentary Elections. The study illustrates that although official communication between Iranian authorities and citizens is a prototypical example of monolingualism and non-translation, voluntary translation happens between Persian and non-Persian speaking individuals, acting as a viable and cost-effective bottom-up alternative for the inclusion of non-Persian speaking peoples, far more effective than an impractical, top-down language policy reform implicitly found in the “Persianization” claim.
Selective Endothelin‐A Receptor Blockade Attenuates Endotoxin‐Induced Pulmonary Hypertension and Pulmonary vascular dysfunction
Authors: Toney Brent M. , Fisher Amanda J. , Albrecht Marjorie , Lockett Angelia D. , Presson Robert G. , Petrache Irina , Lahm Tim
Published: May 2014

Endothelin‐1 is a potent mediator of sepsis‐induced pulmonary hypertension (PH). The pulmonary vascular effects of selective blockade of endothelin receptor subtype A (ETAR) during endotoxemia remain unknown. We hypothesized that selective ETAR antagonism attenuates endotoxin‐induced PH and improves pulmonary artery (PA) vasoreactivity. Adult male Sprague‐Dawley rats (250–450 g) received lipopolysaccharide (LPS; Salmonella typhimurium; 20 mg/kg intraperitoneally) or vehicle 6 hours before hemodynamic assessment and tissue harvest. The selective ETAR antagonist sitaxsentan (10 or 20 mg/kg) or vehicle was injected intravenously 3 hours after receipt of LPS. Right ventricular systolic pressure, mean arterial pressure (MAP), cardiac output (CO), oxygenation (P/F ratio), and serum bicarbonate were measured. Bronchoalveolar lavage (BAL) cell differential and lung wet‐to‐dry ratios were obtained. Endothelium‐dependent and endothelium‐independent vasorelaxations were determined in isolated PA rings. PA interleukin (IL)‐1β, IL‐6, tumor necrosis factor α (TNF‐α), and inducible nitric oxide synthase (iNOS) messenger RNA (mRNA) were measured. LPS caused PH, decreased MAP, CO, and serum bicarbonate, and increased PA IL‐1β, IL‐6, TNF‐α, and iNOS mRNA. Sitaxsentan attenuated sepsis‐induced PH and increased MAP. The P/F ratio, CO, serum bicarbonate, and BAL neutrophilia were not affected by sitaxsentan. In isolated PA rings, while not affecting phenylephrine‐induced vasocontraction or endothelium‐dependent relaxation, sitaxsentan dose‐dependently attenuated LPS‐induced alterations in endothelium‐independent relaxation. PA cytokine mRNA levels were not significantly attenuated by ETAR blockade. We conclude that ETAR blockade attenuates endotoxin‐induced alterations in systemic and PA pressures without negatively affecting oxygenation. This protective effect appears to be mediated not by attenuation of sepsis‐induced cardiac dysfunction, acidosis, or alveolar inflammation but rather by improved endothelium‐independent vasorelaxation.
On-Site Availability of Legionella Testing in Acute Care Hospitals, United States
Authors: Garrison Laurel E. , Shaw Kristin M. S. , McCollum Jeffrey T. , Dexter Carol , Vagnone Paula M. Snippes , Thompson Jamie H. , Giambrone Gregory , White Benjamin , Thomas Stepy , Carpenter L. Rand , Nichols Megin , Parker Erin , Petit Susan , Hicks Lauri A. , Langley Gayle E.
Published: May 2014

We surveyed 399 US acute care hospitals regarding availability of on-site Legionella testing; 300 (75.2%) did not offer Legionella testing on site. Availability varied according to hospital size and geographic location. On-site access to testing may improve detection of Legionnaires disease and inform patient management and prevention efforts.

Infect Control Hosp Epidemiol 2014;35(7):898–900
Eulerian relative equilibria of the curved 3-body problems in 𝐒²
Authors: Zhu Shuqiang
Published: May 2014

We consider the gravitational motion of

n
n

point particles with masses

m
1

m_1

,

m
2

m_2

,

…
\ldots

,

m
n

>
0

m_n>0

on surfaces of constant Gaussian curvature. Based on the work of Diacu and his co-authors, we derive the law of universal gravitation in spaces of constant curvature. Using the results, we examine all possible

3
3

-body configurations that can generate geodesic relative equilibria. We prove the existence of all acute triangle Eulerian relative equilibria and get a necessary and sufficient condition for the existence of obtuse triangle Eulerian relative equilibria. We also show that any three positive masses can generate Eulerian relative equilibria.
Computing the residue of the Dedekind zeta function
Authors: Belabas Karim , Friedman Eduardo
Published: May 2014

Assuming the Generalized Riemann Hypothesis, Bach has shown that one can calculate the residue of the Dedekind zeta function of a number field

K
K

by a clever use of the splitting of primes

p
>
X

p>X

, with an error asymptotically bounded by

8.33
log
⁡

Δ
K

/

(

X

log
⁡
X
)

8.33\log \Delta _K/(\sqrt {X}\log X)

, where

Δ
K

\Delta _K

is the absolute value of the discriminant of

K
K

. Guided by Weil’s explicit formula and still assuming GRH, we make a different use of the splitting of primes and thereby improve Bach’s constant to

2.33
2.33

. This results in substantial speeding of one part of Buchmann’s class group algorithm.
Julia sets on ℝℙ² and dianalytic dynamics
Authors: Goodman Sue , Hawkins Jane
Published: May 2014

We study analytic maps of the sphere that project to well-defined maps on the nonorientable real surface

R
P

2

\mathbb {RP}^2

. We parametrize all maps with two critical points on the Riemann sphere

C

∞

\mathbb {C}_\infty

, and study the moduli space associated to these maps. These maps are also called quasi-real maps and are characterized by being conformally conjugate to a complex conjugate version of themselves. We study dynamics and Julia sets on

R
P

2

\mathbb {RP}^2

of a subset of these maps coming from bicritical analytic maps of the sphere.
The association between cognitive functioning and health-related quality of life in low-grade glioma patients
Authors: Boele Florien W. , Zant Maaike , Heine Emma C.E. , Aaronson Neil K. , Taphoorn Martin J.B. , Reijneveld Jaap C. , Postma Tjeerd J. , Heimans Jan J. , Klein Martin
Published: May 2014

Background

Glioma patients are not only confronted with the diagnosis and treatment of a brain tumor, but also with changes in cognitive and neurological functioning that can profoundly affect their daily lives. At present, little is known about the relationship between cognitive functioning and health-related quality of life (HRQOL) during the disease trajectory. We studied this association in low-grade glioma (LGG) patients with stable disease at an average of 6 years after diagnosis.

Methods

Patients and healthy controls underwent neuropsychological testing and completed self-report measures of generic (MOS SF36) and disease-specific (EORTC BN20) HRQOL. Associations were determined with Pearson correlations, and corrections for multiple testing were made.

Results

We analyzed data gathered from 190 LGG patients. Performance in all cognitive domains was positively associated with physical health (SF36 Physical Component Summary). Executive functioning, processing speed, working memory, and information processing were positively associated with mental health (SF36 Mental Component Summary). We found negative associations between a wide range of cognitive domains and disease-specific HRQOL scales.

Conclusions

In stable LGG patients, poorer cognitive functioning is related to lower generic and disease-specific HRQOL. This confirms that cognitive assessment of LGG patients should not be done in isolation from assessment of its impact on HRQOL, both in clinical and in research settings.
Early Modern Portugal
Authors: Paiva José Pedro , Jesus Roger Lee
Published: May 2014

During the first decades of the Early Modern period, due to discoveries made by Portuguese explorers, Portugal acquired one of the earliest and most important European overseas empires. Over the course of three centuries, close links were established with Africa, America, and Asia in a dynamic move mediated by means of the sea. This was an epoch in which Portugal constituted a central player in great world transformations. Its dramatic opening to the wider world provoked deep changes at different levels inside the realm, from central political organization, in which the king and his court played a central role, to trade, society, and even the identity of Portugal and the self-perception of being Portuguese. Little affected by the religious break occasioned by Protestantism that shook central and northern Europe, though facing the challenge posed by the presence of a large group of Jewish descendants who were baptized forcibly in 1497, the kingdom embarked on its new course without cutting links with Europe, which some elites continued to view, until the late 18th century, as an inspiring intellectual, cultural, and artistic center. The leading role played by Portugal was marked by a hiatus between 1580 and 1640, a period during which, due to a dynastic crisis caused by the death of King Sebastian during a battle in North Africa, it was ruled by the Spanish Habsburg monarchy in an arrangement in which the country enjoyed a loose political autonomy. After 1640, with a new dynasty in charge, the kingdom faced severe difficulties, most especially until 1668. In the course of the 17th century when Portuguese overseas interests were attacked by the Dutch and the English, the center of the empire slowly moved from the Indian Ocean to the Atlantic. This shift in geographic emphasis together with the discovery of diamonds and gold mines in Brazil led, by the end of the 17th century, to a period of economic growth that lasted until the first half of the 18th century. During this period, the Crown profited by reinforcing its power both internally and externally. Influenced by Enlightenment doctrines that were accompanied, simultaneously and paradoxically, by use of repressive methods, the government, after the earthquake that destroyed Lisbon in 1755, instituted deep reforms, which were were set up under the leadership of Carvalho e Melo (Marquis of Pombal), who gained the favor of the king as chief minister until 1777. The historiography on early modern Portugal is rich, particularly in works published by Portuguese authors after the 1970s. The following entries are limited to the most representative essays in each of the different topics: political history, Portuguese empire, diplomatic history, economic history, social history and welfare, cultural history, religious history, art history, and local history.
Early Childhood Teacher Education
Authors: Nuttall Joce
Published: May 2014

Early childhood teacher education (ECTE) is focused on the preparation of educators who educate and care for our youngest citizens. The years from birth to eight years of age are generally considered early childhood, yet most programs of ECTE focus on the prior-to-school years and the periods variously known as infancy, toddlerhood, the young child, preschool, pre-K, kindergarten, and the early years (with the two last terms also applying to the beginning of formal schooling in some countries). Research in ECTE is also a subset of the wider teacher education research field, and ECTE researchers are engaged in many of the same debates. These debates include how best to prepare graduates to teach diverse and disadvantaged students in equitable ways, and the most appropriate forms of curriculum and pedagogy for the education of young children. For this reason, scholars of ECTE are advised to also study the related Oxford Bibliographies articles “Teacher Preparation” and “Teacher Training and Development.” Debates about ECTE are intensifying around the world at present as governments take increase their policy focus on early childhood education. Teacher qualifications are a recognized factor in the quality of early childhood programs, leading to an increased focus on the efficacy of ECTE and the capacity of teacher education institutions to attract and retain suitable candidates. Further challenges for scholars of ECTE include the wide diversity of services available for young children and their families in most countries, and the wide range of staff qualifications typically found in these services. The entries in this article attempt to navigate through this complex field but are principally drawn from descriptions of ECTE in university settings (since this environment is where most ECTE research occurs) and involving candidates who will work in the prior-to-school years. Two important themes thread through every section of this article. The first is the emphasis on describing personal and professional perspectives, particular of ECTE, within this literature. This emphasis is related to the second theme, which is the dominance of small-scale, single-cohort studies confined to individual institutions. There is a pressing need for more studies in ECTE that work with large data sets and that conduct research across institutions and across national borders, if scholars in ECTE are to respond effectively to global flows in policy, research, and practice.
The Social Construction of Parental Gender Preferences
Authors: Kane Emily W.
Published: May 2014

Parents play a critical role in shaping gender-related outcomes for their children, from the moment of birth or adoption and often even before. Parental beliefs, preferences, assumptions, and actions have been analyzed by social scientists and practitioners in a variety of disciplines, especially psychology, sociology, education, and communications, as well as interdisciplinary fields like gender and sexuality studies, childhood studies, and family studies. This multidisciplinary literature documents tendencies toward gender differentiated parenting from infancy through adolescence, with a wide range of specific topics such as vocalization to infants, the selection of toys and activities, the assignment of chores, the way emotional expression is managed, and the kinds of educational fields encouraged. The literature documents how parental preferences and actions in these arenas and many more can contribute to the social construction of gendered outcomes during childhood, encouraging boys and girls to develop different skills, interests, and capacities, with particularly limiting expectations sometimes evident for boys. Scholars and practitioners have also addressed the implications of parental gendering for children’s adult lives in terms of gender differentiation and gender inequalities. Within this broader general tendency toward parents preferring and crafting gender differentiated outcomes, the literature also reveals change over time in some aspects of parental preferences and actions, including recently increased attention to parental responses to transgender children, as well as variation across subgroups of parents and children. Particularly important subgroup variations are between mothers and fathers, and across groups defined by intersecting inequalities of race, class, sexuality, and nation. In addition, researchers have documented various factors that shape parental preferences, ranging from public policy and expert advice to everyday accountability to friends, relatives, and strangers. Even within the literature focused on the role of parents, attention is focused on the importance of many other sources of influence on gendered outcomes among children, ranging from biology to teachers, peers, siblings, media, government policies, and the active agency of children themselves. An intersecting but less centrally reviewed set of literatures within economics and demography also documents differential preference for and investment in sons and daughters; though not the central focus of this article, some sources that offer an overview of key patterns in those literatures are included throughout.
New Zealand Cinema
Authors: Fox Alistair
Published: May 2014

New Zealand cinema, despite the relatively small number of feature films produced, has received much international attention, acquiring a reputation as often punching above its weight. Since A Cinema of Unease: A Personal Journey by Sam Neill (directed by Sam Neill and Judy Rymer, 1995), it has frequently been viewed as distinguished by dark undertones; the representation of perturbed states of mind; the depiction of familial, social, and political dysfunction; and the privileging of a Gothic mode, and genres such as the psychodrama, crime film, and horror that undermine the myth of New Zealand as “God’s own country.” In this article, “New Zealand films” are defined as those made primarily by New Zealanders, in New Zealand, and on New Zealand subjects, rather than the runaway productions, funded from the United States but shot in New Zealand, that have become increasingly prominent in the film industry’s landscape since 2000, with the encouragement of the New Zealand government. While documentary filmmaking has been strongly represented since 1898, fiction films began to be made in significant numbers only after the late 1970s, in what has become known as the New Zealand New Wave, which saw the emergence of filmmakers such as Roger Donaldson, Geoff Murphy, and Vincent Ward, who would go on to have successful international careers. It also witnessed the appearance of a cycle of films about and for women, and of female filmmakers such as Alison Maclean and Gaylene Preston. This initial flowering was followed in the 1990s by a Second Wave, in which directors came to prominence who are now considered major filmmakers in the international stage: not only Peter Jackson, who, while remaining based in New Zealand, has brought Hollywood to “Wellywood” with The Lord of the Rings and subsequent films, but also Jane Campion, regarded as one of the world’s most significant woman filmmakers. The rise of fiction filmmaking also saw the emergence of Maori filmmakers such as Barry Barclay and Merata Mita, whose work constituted some of the earliest features anywhere to be made by members of an indigenous minority, from an indigenous perspective. Since the turn of the twenty-first century, New Zealand filmmaking has witnessed an expansion to address the presence of other significant ethnic minorities, reflecting New Zealand’s increasingly multicultural social composition. Critical writing on New Zealand cinema is still in its infancy, with many films and filmmakers having received, so far, little or no scholarly attention.
Football
Authors: Iber Jorge
Published: May 2014

From the start of the field of sports history as a recognized academic endeavor in the early 1970s, one of the major areas of the genre has been to document how racial and ethnic minorities have played, participated in, and utilized sports for various purposes. In regard to American football, the volume of research is prodigious and many works have focused upon the role of African Americans and Native Americans in this sport (both at the professional and collegiate level). In addition to these groups, Gerald Gems’s For Pride, Profit and Patriarchy demonstrates how the gridiron was utilized to transmit American cultural values to “white ethnics” who came to the United States in the early part of the 20th century (Gems 2000, cited under General Overviews). While much has been learned about the significance and history of football players of these backgrounds, Latinos and their contribution to the sport (at all levels) have generated far less academic interest.