bluuebunny/crossref_metadata_2025 huggingface dataset:
The excitation of geodesic acoustic mode flows by a resonant magnetic field and by resonant heating
Authors: Kleva Robert G. , Hassam A. B.
Published: March 2013

Toroidal magnetohydrodynamic (MHD) simulations demonstrate that sheared poloidal flows in tokamaks can be generated by the resonant excitation of the geodesic acoustic mode (GAM). Poloidal flows are generated by two resonant excitation methods: oscillating currents in an external coil and an oscillating heat source. The coil current and the heat source oscillate in time at the local GAM frequency. The sheared poloidal flow generated by the excitation of the GAM may be useful for the suppression of plasma instabilities.
Landau damping in a turbulent setting
Authors: Plunk G. G.
Published: March 2013

To address the problem of Landau damping in kinetic turbulence, we consider the forcing of the linearized Vlasov equation by a stationary random source. It is found that the time-asymptotic density response is dominated by resonant particle interactions that are synchronized with the source. The energy consumption of this response is calculated, implying an effective damping rate, which is the main result of this paper. Evaluating several cases, it is found that the effective damping rate can differ from the Landau damping rate in magnitude and also, remarkably, in sign. A limit is demonstrated in which the density and current become phase-locked, which causes the effective damping to be negligible; this result offers a fresh perspective from which to reconsider recent observations of kinetic turbulence satisfying critical balance.
Fabrication and optical properties of large-scale arrays of gold nanocavities based on rod-in-a-tube coaxials
Authors: Murphy A. , Sonnefraud Y. , Krasavin A. V. , Ginzburg P. , Morgan F. , McPhillips J. , Wurtz G. , Maier S. A. , Zayats A. V. , Pollard R.
Published: March 2013

Centimeter sized arrays of gold coaxial rod-in-a tube cavities have been fabricated using anodized aluminum oxide as a template. The etching process used to create the cavities enables the production of extremely small gaps between tube and rod, on the order of 5 nm, smaller than those created by standard fabrication techniques. Normal incidence spectroscopy reveals two extinction peaks in the visible and near infrared wavelength range associated with resonant plasmonic modes excited in the structure. Numerical simulations show that the modes are associated with in-phase and out-of-phase hybridization of transverse dipolar excitations in the nanorod and in the tube.
Determination of the inductance of imploding wire array Z-pinches using measurements of load voltage
Authors: Burdiak G. C. , Lebedev S. V. , Hall G. N. , Harvey-Thompson A. J. , Suzuki-Vidal F. , Swadling G. F. , Khoory E. , Pickworth L. , Bland S. N. , de Grouchy P. , Skidmore J.
Published: March 2013

The inductance of imploding cylindrical wire array z-pinches has been determined from measurements of load voltage and current. A thorough analysis method is presented that explains how the load voltage of interest is found from raw signals obtained using a resistive voltage divider. This method is applied to voltage data obtained during z-pinch experiments carried out on the MAGPIE facility (1.4 MA, 240 ns rise-time) in order to calculate the load inductance and thereafter the radial trajectory of the effective current sheath during the snowplough implosion. Voltage and current are monitored very close to the load, allowing these calculations to be carried out without the need for circuit modelling. Measurements give a convergence ratio for the current of between 3.1 and 5.7 at stagnation of the pinch.
Temporal coupled mode theory for thermal emission from a single thermal emitter supporting either a single mode or an orthogonal set of modes
Authors: Zhu Linxiao , Sandhu Sunil , Otey Clayton , Fan Shanhui , Sinclair Michael B. , Shan Luk Ting
Published: March 2013

We propose a temporal coupled mode theory for thermal emission from a single emitter supporting either a single mode or an orthogonal set of modes. This temporal coupled mode theory provides analytic insights into the general behaviors of resonant thermal emitters. We validate the coupled mode theory formalism by a direct numerical simulation of the emission properties of single emitters.
Focus group interviews with older Australians to explore their awareness of the national age-adjusted dietary recommendations and their suggestions for assisting them to meet these dietary targets
Authors: Brownie Sonya , Coutts Rosanne
Published: March 2013

Promoting a healthy, nutritious diet is central to the goal of assisting individuals to age well. This study used focus groups to explore older people’s awareness of the current age-adjusted nutrient recommendations and age-adjusted core food groups, and to capture their views about these dietary guidelines. Thematic analysis was applied to aggregate data into categories of frequently occurring responses. Data were collected from five focus groups: a total of 29 participants, aged 60–98 years of age. Analysis of responses revealed that participants were generally unaware of government-endorsed dietary guidelines or nutrient recommendations for older people. Their suggestions for assisting older people to meet these age-adjusted dietary targets included: targeted media campaigns to raise awareness about older people’s nutrient requirements; the need for practical meal plans that do meet their dietary needs; and the removal of barriers to supermarket food choices, such as problems with opening jars and excessive packaging.
Lateral root morphogenesis is dependent on the mechanical properties of the overlaying tissues
Authors: Lucas Mikaël , Kenobi Kim , von Wangenheim Daniel , Voβ Ute , Swarup Kamal , De Smet Ive , Van Damme Daniël , Lawrence Tara , Péret Benjamin , Moscardi Eric , Barbeau Daniel , Godin Christophe , Salt David , Guyomarc’h Soazig , Stelzer Ernst H. K. , Maizel Alexis , Laplaze Laurent , Bennett Malcolm J.
Published: March 2013

In
Arabidopsis
, lateral root primordia (LRPs) originate from pericycle cells located deep within the parental root and have to emerge through endodermal, cortical, and epidermal tissues. These overlaying tissues place biomechanical constraints on the LRPs that are likely to impact their morphogenesis. This study probes the interplay between the patterns of cell division, organ shape, and overlaying tissues on LRP morphogenesis by exploiting recent advances in live plant cell imaging and image analysis. Our 3D/4D image analysis revealed that early stage LRPs exhibit tangential divisions that create a ring of cells corralling a population of rapidly dividing cells at its center. The patterns of division in the latter population of cells during LRP morphogenesis are not stereotypical. In contrast, statistical analysis demonstrated that the shape of new LRPs is highly conserved. We tested the relative importance of cell division pattern versus overlaying tissues on LRP morphogenesis using mutant and transgenic approaches. The double mutant
aurora1
(
aur1
)
aur2
disrupts the pattern of LRP cell divisions and impacts its growth dynamics, yet the new organ’s dome shape remains normal. In contrast, manipulating the properties of overlaying tissues disrupted LRP morphogenesis. We conclude that the interaction with overlaying tissues, rather than the precise pattern of divisions, is most important for LRP morphogenesis and optimizes the process of lateral root emergence.
Orbital-scale climate forcing of grassland burning in southern Africa
Authors: Daniau Anne-Laure , Sánchez Goñi Maria Fernanda , Martinez Philippe , Urrego Dunia H. , Bout-Roumazeilles Viviane , Desprat Stéphanie , Marlon Jennifer R.
Published: March 2013

Although grassland and savanna occupy only a quarter of the world's vegetation, burning in these ecosystems accounts for roughly half the global carbon emissions from fire. However, the processes that govern changes in grassland burning are poorly understood, particularly on time scales beyond satellite records. We analyzed microcharcoal, sediments, and geochemistry in a high-resolution marine sediment core off Namibia to identify the processes that have controlled biomass burning in southern African grassland ecosystems under large, multimillennial-scale climate changes. Six fire cycles occurred during the past 170,000 y in southern Africa that correspond both in timing and magnitude to the precessional forcing of north–south shifts in the Intertropical Convergence Zone. Contrary to the conventional expectation that fire increases with higher temperatures and increased drought, we found that wetter and cooler climates cause increased burning in the study region, owing to a shift in rainfall amount and seasonality (and thus vegetation flammability). We also show that charcoal morphology (i.e., the particle's length-to-width ratio) can be used to reconstruct changes in fire activity as well as biome shifts over time. Our results provide essential context for understanding current and future grassland-fire dynamics and their associated carbon emissions.
Governance regime and location influence avoided deforestation success of protected areas in the Brazilian Amazon
Authors: Nolte Christoph , Agrawal Arun , Silvius Kirsten M. , Soares-Filho Britaldo S.
Published: March 2013

Protected areas in tropical countries are managed under different governance regimes, the relative effectiveness of which in avoiding deforestation has been the subject of recent debates. Participants in these debates answer appeals for more strict protection with the argument that sustainable use areas and indigenous lands can balance deforestation pressures by leveraging local support to create and enforce protective regulations. Which protection strategy is more effective can also depend on (i) the level of deforestation pressures to which an area is exposed and (ii) the intensity of government enforcement. We examine this relationship empirically, using data from 292 protected areas in the Brazilian Amazon. We show that, for any given level of deforestation pressure, strictly protected areas consistently avoided more deforestation than sustainable use areas. Indigenous lands were particularly effective at avoiding deforestation in locations with high deforestation pressure. Findings were stable across two time periods featuring major shifts in the intensity of government enforcement. We also observed shifting trends in the location of protected areas, documenting that between 2000 and 2005 strictly protected areas were more likely to be established in high-pressure locations than in sustainable use areas and indigenous lands. Our findings confirm that all protection regimes helped reduce deforestation in the Brazilian Amazon.
Evolution and stability of ring species
Authors: Martins Ayana B. , de Aguiar Marcus A. M. , Bar-Yam Yaneer
Published: March 2013

Neutral models, in which genetic change arises through random variation without fitness differences, have proven remarkably successful in describing observed patterns of biodiversity, despite the manifest role of selection in evolution. Here we investigate the effect of barriers on biodiversity by simulating the expansion of a population around a barrier to form a ring species, in which the two ends of the population are reproductively isolated despite ongoing gene flow around the ring. We compare the spatial and genetic properties of a neutral agent-based population model to the greenish warblers’ complex, a well-documented example of an actual ring species in nature. Our results match the distribution of subspecies, the principal components of genetic diversity, and the linear spatial–genetic correlation of the observed data, even though selection is expected to be important for traits of this species. We find that ring species are often unstable to speciation or mixing but can persist for extended times depending on species and landscape features. For the greenish warblers, our analysis implies that the expanded area near the point of secondary contact is important for extending the duration of the ring, and thus, for the opportunity to observe this ring species. Nevertheless it also suggests the ring will break up into multiple species in 10,000 to 50,000 y. These results imply that simulations can be used to accurately describe empirical data for complex spatial–genetic traits of an individual species.
Anti-inflammatory role of PGD
2
in acute lung inflammation and therapeutic application of its signal enhancement
Authors: Murata Takahisa , Aritake Kosuke , Tsubosaka Yoshiki , Maruyama Toshihiko , Nakagawa Takayuki , Hori Masatoshi , Hirai Hiroyuki , Nakamura Masataka , Narumiya Shuh , Urade Yoshihiro , Ozaki Hiroshi
Published: March 2013

We investigated the role of prostaglandin D
2
(PGD
2
) signaling in acute lung injury (ALI), focusing on its producer–effector interaction in vivo. Administration of endotoxin increased edema and neutrophil infiltration in the WT mouse lung. Gene disruption of hematopoietic PGD synthase (H-PGDS) aggravated all of the symptoms. Experiments involving bone marrow transplantation between WT and H-PGDS–deficient mice showed that PGD
2
derived from alveolar nonhematopoietic lineage cells (i.e., endothelial cells and epithelial cells) promotes vascular barrier function during the early phase (day 1), whereas neutrophil-derived PGD
2
attenuates its own infiltration and cytokine expression during the later phase (day 3) of ALI. Treatment with either an agonist to the PGD
2
receptor, DP, or a degradation product of PGD
2
, 15-deoxy-Δ
12,14
-PGJ
2
, exerted a therapeutic action against ALI. Data obtained from bone marrow transplantation between WT and DP-deficient mice suggest that the DP signal in alveolar endothelial cells is crucial for the anti-inflammatory reactions of PGD
2
. In vitro, DP agonism directly enhanced endothelial barrier formation, and 15-deoxy-Δ
12,14
-PGJ
2
attenuated both neutrophil migration and cytokine expression. These observations indicate that the PGD
2
signaling between alveolar endothelial/epithelial cells and infiltrating neutrophils provides anti-inflammatory effects in ALI, and suggest the therapeutic potential of these signaling enhancements.
Reversible epigenetic down-regulation of MHC molecules by devil facial tumour disease illustrates immune escape by a contagious cancer
Authors: Siddle Hannah V. , Kreiss Alexandre , Tovar Cesar , Yuen Chun Kit , Cheng Yuanyuan , Belov Katherine , Swift Kate , Pearse Anne-Maree , Hamede Rodrigo , Jones Menna E. , Skjødt Karsten , Woods Gregory M. , Kaufman Jim
Published: March 2013

Contagious cancers that pass between individuals as an infectious cell line are highly unusual pathogens. Devil facial tumor disease (DFTD) is one such contagious cancer that emerged 16 y ago and is driving the Tasmanian devil to extinction. As both a pathogen and an allograft, DFTD cells should be rejected by the host–immune response, yet DFTD causes 100% mortality among infected devils with no apparent rejection of tumor cells. Why DFTD cells are not rejected has been a question of considerable confusion. Here, we show that DFTD cells do not express cell surface MHC molecules in vitro or in vivo, due to down-regulation of genes essential to the antigen-processing pathway, such as β2-microglobulin and transporters associated with antigen processing. Loss of gene expression is not due to structural mutations, but to regulatory changes including epigenetic deacetylation of histones. Consequently, MHC class I molecules can be restored to the surface of DFTD cells in vitro by using recombinant devil IFN-γ, which is associated with up-regulation of the MHC class II transactivator, a key transcription factor with deacetylase activity. Further, expression of MHC class I molecules by DFTD cells can occur in vivo during lymphocyte infiltration. These results explain why T cells do not target DFTD cells. We propose that MHC-positive or epigenetically modified DFTD cells may provide a vaccine to DFTD. In addition, we suggest that down-regulation of MHC molecules using regulatory mechanisms allows evolvability of transmissible cancers and could affect the evolutionary trajectory of DFTD.
E3 ligase WWP2 negatively regulates TLR3-mediated innate immune response by targeting TRIF for ubiquitination and degradation
Authors: Yang Yan , Liao Bing , Wang Suyun , Yan Bingru , Jin Ying , Shu Hong-Bing , Wang Yan-Yi
Published: March 2013

Recognition of viral double-stranded RNA by Toll-like receptor 3 (TLR3) triggers activation of the transcription factors NF-κB and interferon regulated factor 3, leading to induction of type I interferons and proinflammatory cytokines. TIR-domain–containing adapter-inducing interferon-β (TRIF) is an adapter protein required for TLR3-mediated signaling. Here we identified the E3 ubiquitin ligase WW domain-containing protein 2 (WWP2) as a TRIF-associated protein by biochemical purification. WWP2 mediated K48-linked ubiquitination and degradation of TRIF upon TLR3 activation. Overexpression of WWP2 inhibited TLR3-mediated NF-κB and interferon regulated factor 3 activation, whereas knockdown of WWP2 had opposite effects. We generated
Wwp2
-deficient mice to further investigate the roles of Wwp2 in innate immune responses. Consistently, production of IFN-β, CCL5, TNFα, and IL-6 in response to the TLR3 ligand poly(I:C) was elevated in
Wwp2

−/−

macrophages and
Wwp2
-deficient mice exhibited increased susceptibility to poly(I:C)-induced death than the control littermates. Our findings suggest that WWP2 negatively regulates TLR3-mediated innate immune and inflammatory responses by targeting TRIF for ubiquitination and degradation.
Polar transmembrane interactions drive formation of ligand-specific and signal pathway-biased family B G protein-coupled receptor conformations
Authors: Wootten Denise , Simms John , Miller Laurence J. , Christopoulos Arthur , Sexton Patrick M.
Published: March 2013

Recently, the concept of ligand-directed signaling—the ability of different ligands of an individual receptor to promote distinct patterns of cellular response—has gained much traction in the field of drug discovery, with the potential to sculpt biological response to favor therapeutically beneficial signaling pathways over those leading to harmful effects. However, there is limited understanding of the mechanistic basis underlying biased signaling. The glucagon-like peptide-1 receptor is a major target for treatment of type-2 diabetes and is subject to ligand-directed signaling. Here, we demonstrate the importance of polar transmembrane residues conserved within family B G protein-coupled receptors, not only for protein folding and expression, but also in controlling activation transition, ligand-biased, and pathway-biased signaling. Distinct clusters of polar residues were important for receptor activation and signal preference, globally changing the profile of receptor response to distinct peptide ligands, including endogenous ligands glucagon-like peptide-1, oxyntomodulin, and the clinically used mimetic exendin-4.
147
Sm-
143
Nd systematics of Earth are inconsistent with a superchondritic Sm/Nd ratio
Authors: Huang Shichun , Jacobsen Stein B. , Mukhopadhyay Sujoy
Published: March 2013

The relationship between the compositions of the Earth and chondritic meteorites is at the center of many important debates. A basic assumption in most models for the Earth’s composition is that the refractory elements are present in chondritic proportions relative to each other. This assumption is now challenged by recent
142
Nd/
144
Nd ratio studies suggesting that the bulk silicate Earth (BSE) might have an Sm/Nd ratio 6% higher than chondrites (i.e., the BSE is superchondritic). This has led to the proposal that the present-day
143
Nd/
144
Nd ratio of BSE is similar to that of some deep mantle plumes rather than chondrites. Our reexamination of the long-lived
147
Sm-
143
Nd isotope systematics of the depleted mantle and the continental crust shows that the BSE, reconstructed using the depleted mantle and continental crust, has
143
Nd/
144
Nd and Sm/Nd ratios close to chondritic values. The small difference in the ratio of
142
Nd/
144
Nd between ordinary chondrites and the Earth must be due to a process different from mantle-crust differentiation, such as incomplete mixing of distinct nucleosynthetic components in the solar nebula.
Cell-free study of F plasmid partition provides evidence for cargo transport by a diffusion-ratchet mechanism
Authors: Vecchiarelli Anthony G. , Hwang Ling Chin , Mizuuchi Kiyoshi
Published: March 2013

Significance

ParA-type partition systems self-organize and pattern the bacterial nucleoid to organize plasmids, chromosomes, and protein machinery spatially. To study how protein patterns generate cargo movement, we reconstituted and visualized the partition system of F plasmid using a DNA-carpeted flowcell as an artificial nucleoid surface. We found that the partition proteins could bridge plasmid to the DNA carpet dynamically and mediate plasmid motion. Our data favor a diffusion-ratchet mechanism inherently different from classical motor protein or actin/microtubule filament-based transport. We expect surface-mediated patterning to become increasingly recognized as a means of intracellular transport in all kingdoms of life.
“Preferring Omission over Falsity”
Authors: Vedal Nathan
Published: March 2013

Neglected in the current scholarship on Qing dynasty court compilations, the dictionary commissioned by the Kangxi emperor in 1710 is an important source for understanding the nature of court-commissioned reference works in the early Qing. TheKangxi Classic of Characters, although typically believed to have improved on Ming and early Qing dictionaries by virtue of its greater inclusion of source materials, in fact had a more complicated relationship with its predecessors. In the process of delegitimizing earlier, privately compiled works, the editors of theKangxi Classic of Charactersactively promoted the exclusive authority of the court in their composition of dictionary definitions. Further, their manipulation of definitions in earlier dictionaries was not a straightforward process of greater inclusion and deletion of redundancy, but rather a reflection of contemporary intellectual developments. This can be seen in the compilers’ attempts to bring the definitions in line with a number of trends in Confucian thought, which were taking form at the court during this period.
Les premières grammaires françaises à l’usage des Persans
Authors: Bechraoui Mohamed-Fadhel
Published: March 2013

Après la tentative non aboutie d’Eugène Boré (1816–1891) en 1839, la première grammaire française à l’usage des Persans ne paraît qu’en 1882 sous le titre d’Orthographie française ou Règles de l’orthographe de la langue française simplifiée et rendues à leurs principes naturels. L’auteur, Jules Richard (1816–1891), n’y développe que la partie consacrée aux articulations et aux parties du discours et ne parvient jamais à publier l’intégralité de l’ouvrage qu’il avait rédigé à l’attention des élèves de l’école polytechnique de Téhéran et qui est censé contenir une partie propre à la syntaxe. Son fils Joseph Richard (1285 [1868/69] – 1354 [1935/36]) tentera de rectifier le tir en publiant laNouvelle méthode pratique et facile pour apprendre la langue française(21894), une sorte de ‘méthode Ahn’ où la grammaire ne figure qu’en abrégé sous forme de définitions ou d’applications. L’Orthographiese caractérise spécialement par le nombre des questions théoriques discutées en notes entièrement rédigées en français, par le recours à des termes grammaticaux peu communs, par la traduction originale, en persan, de certains termes français, ainsi que par la neutralisation de certaines oppositions verbales dans la traduction des paradigmes du français.
Die Pallas-Redaktion der PetersburgerVocabularia comparativaund ihre Bedeutung für die Entwicklung der slavischen Sprachwissenschaft
Authors: Keipert Helmut
Published: March 2013

Die 1787–1789 in St. Petersburg von Peter Simon Pallas (1741–1811) gedrucktenVocabularia comparativader Zarin Katharina II. enthalten zu 285 mehr oder weniger elementaren russischen Wörtern Entsprechungen in 200 Sprachen. Den auf den Zeilen 1–12 prominent platzierten slavischen Teil hat Josef Dobrovský (1753–1829) in seinerVergleichung der Russischen und Böhmischen Sprache(1796) recht kritisch besprochen. Vor allem hat er darin die unbefriedigende Dokumentation des Tschechischen und Slovakischen und deren merkwürdige und z.T. fehlerhafte kyrillische Transkription zu verbessern gesucht, manche bessere Äquivalente vorgeschlagen und in seinen Kommentaren häufig auf die unterschiedlichen Lautungen in den slavischen Wörtern ein und desselben Lemmas hingewiesen. Schon 1794 hat er erkannt, dass in mehreren Fällen die Verteilung dieser Unterschiede regelmäßig zu sein scheint und eine areale Aufteilung der slavischen Sprachen in eine südöstliche und eine nordwestliche Gruppe (Russisch und Serbisch vs. Polnisch und Tschechisch) anzunehmen nahelegt. Noch in den neunziger Jahren hat er eine verbesserte Ausgabe des Wörterbuchs zu planen begonnen, dafür u.a. 1815 die bei Pallas noch fehlende kajkavische Wortliste publiziert und mit seinerVergleichungals Vorbild 1822 Vuk Karadžić (1787–1864) zur Verbesserung der serbischen Liste und zur Erstellung einer bulgarischen angeregt. Überzeugend lässt sich zeigen, dass die von Aleksandr Vostokov (1781–1864) 1820 eingeführte und bis heute verbreitete Aufteilung der slavischen Sprachen in drei Gruppen (Ost-, West- und Südslavisch) direkt an Dobrovskýs Vorschlag anschließt und in mancher Hinsicht von dessen sorgfältiger Verbesserung der Mängel und Inkonsequenzen in den slavischen Einträgen derVocabularia comparativaprofitiert hat.
A Vygotskian sociocultural perspective on immersion education
Authors: Swain Merrill , Lapkin Sharon
Published: March 2013

An enduring issue in immersion education focuses on the appropriate use of the L1 in the one-way or two-way immersion classroom. In this article we discuss several key constructs (mediation, languaging, the cognition/emotion relationship, zone of proximal development) that are central to a Vygotskian sociocultural theory of mind perspective on second language learning and teaching. Each discussion of a theoretical construct is followed by a review of one or more key research studies from one-way or two-way immersion contexts whose findings we highlight or re-interpret in light of Vygotsky’s insights. The theory and research yield three important guiding principles with the goal of helping educators to make decisions about their language use choices in the immersion classroom.
“I’m sorry, flower”
Authors: Burdelski Matthew
Published: March 2013

Apologies have long been considered an important social action in many languages for dealing with frictions of everyday interaction and restoring interpersonal harmony in response to an offense. Although there has been an increasing amount of research on apologies in non-Western languages, little research involves children. Japan is an interesting case in which to examine apologies. In particular, Japan has been called a “culture of apology” in the sense that speakers often ‘apologize’ (ayamaru) in a wide range of communicative contexts. This article examines children’s socialization to a culture of apology as evidenced by a large corpus of audiovisual recordings made over the last decade in households, playgrounds, and a preschool in Japan. In particular, it examines ways Japanese caregivers (e.g. parents, preschool teachers) use the expressions Gomen ne and Gomen-nasai ([I’m/We’re] sorry) when addressing third parties, including not only other people (e.g. children’s peers) but also a range of entities in the surround (e.g. animals, supernatural objects, objects in the environment such as a stone), and ways they prompt children to say these expressions to such third parties. This analysis suggests that apology situations are an important site through which children are socialized to empathy and relationships in the social world. It also examines ways children use these expressions when addressing peers and inanimate objects, and ways they prompt others including peers and even on occasion adults to say them. These findings suggest that while children deploy strategies in ways that reflect the socialization process, they also deploy them in ways that construct this process in creative ways.
Orthographic cues to word stress in German
Authors: Beyermann Sandra
Published: March 2013

This paper reports a corpus study that addresses the question whether distributional patterns of certain letter strings are orthographic cues to stress in German word reading. For that purpose, the occurrence of stress patterns with a different number of final consonant letters as well as with specific word endings in disyllabic German noun lemmas were investigated. The findings indicate that distributional properties of word endings can serve as reliable orthographic cues to word stress in disyllabic nouns — irrespective of whether they are polymorphemic or simplex nouns. Likewise, the number of final consonant letters is a potential orthographic cue to word stress in disyllabic simplex nouns. Such orthographic cues to stress may be employed during phonological recoding of written words by skilled readers of German.
A note on Unger’s “What linguistic units do Chinese characters represent?”
Authors: Sproat Richard
Published: March 2013

Unger (2011) observes that Chinese characters do not observe a Zipfian distribution, and he uses this fact as evidence that Chinese characters do not represent words. He then goes on to suggest that they do not represent morphemes either. In this note I argue that Unger’s observation is neither new, nor is it necessary; and that, at least with respect to his claim about morphemes, it does not support the conclusion he wishes to make.
Fixating picture boundaries does not eliminate boundary extension: Implications for scene representation
Authors: Michod Gagnier Kristin , Dickinson Christopher A. , Intraub Helene
Published: March 2013

Observers frequently remember seeing more of a scene than was shown (boundary extension). Does this reflect a lack of eye fixations to the boundary region? Single-object photographs were presented for 14–15 s each. Main objects were either whole or slightly cropped by one boundary, creating a salient marker of boundary placement. All participants expected a memory test, but only half were informed that boundary memory would be tested. Participants in both conditions made multiple fixations to the boundary region and the cropped region during study. Demonstrating the importance of these regions, test-informed participants fixated them sooner, longer, and more frequently. Boundary ratings (Experiment 1) and border adjustment tasks (Experiments 2–4) revealed boundary extension in both conditions. The error was reduced, but not eliminated, in the test-informed condition. Surprisingly, test knowledge and multiple fixations to the salient cropped region, during study and at test, were insufficient to overcome boundary extension on the cropped side. Results are discussed within a traditional visual-centric framework versus a multisource model of scene perception.
O-acetylated N-acetylneuraminic acid as a novel target for therapy in human pre-B acute lymphoblastic leukemia
Authors: Parameswaran Reshmi , Lim Min , Arutyunyan Anna , Abdel-Azim Hisham , Hurtz Christian , Lau Kam , Müschen Markus , Yu Robert K. , von Itzstein Mark , Heisterkamp Nora , Groffen John
Published: March 2013

The development of resistance to chemotherapy is a major cause of relapse in acute lymphoblastic leukemia (ALL). Though several mechanisms associated with drug resistance have been studied in detail, the role of carbohydrate modification remains unexplored. Here, we investigated the contribution of 9-O-acetylated N-acetylneuraminic acid (Neu5Ac) to survival and drug resistance development in ALL cells. A strong induction of 9-O-acetylated Neu5Ac including 9-O-acetyl GD3 was detected in ALL cells that developed resistance against vincristine or nilotinib, drugs with distinct cytotoxic mechanisms. Removal of 9-O-acetyl residues from Neu5Ac on the cell surface by an O-acetylesterase made ALL cells more vulnerable to such drugs. Moreover, removal of intracellular and cell surface–resident 9-O-acetyl Neu5Ac by lentiviral transduction of the esterase was lethal to ALL cells in vitro even in the presence of stromal protection. Interestingly, expression of the esterase in normal fibroblasts or endothelial cells had no effect on their survival. Transplanted mice induced for expression of the O-acetylesterase in the ALL cells exhibited a reduction of leukemia to minimal cell numbers and significantly increased survival. This demonstrates that Neu5Ac 9-O-acetylation is essential for survival of these cells and suggests that Neu5Ac de-O-acetylation could be used as therapy to eradicate drug-resistant ALL cells.
Typical operators admit common cyclic vectors
Authors: Zorin-Kranich Pavel
Published: March 2013

Given a countable dense subset

D
D

of an infinite-dimensional separable Hilbert space

H
H

, the set of operators for which every vector in

D
D

except zero is hypercyclic (weakly supercyclic) is residual for the strong (resp. weak) operator topology in the unit ball of

L
(
H
)

L(H)

multiplied by

R
>
1

R>1

(resp.

R
>
0

R>0

).
Sp100A promotes chromatin decondensation at a cytomegalovirus-promoter–regulated transcription site
Authors: Newhart Alyshia , Negorev Dmitri G. , Rafalska-Metcalf Ilona U. , Yang Tian , Maul Gerd G. , Janicki Susan M.
Published: March 2013

Promyelocytic leukemia nuclear bodies (PML-NBs)/nuclear domain 10s (ND10s) are nuclear structures that contain many transcriptional and chromatin regulatory factors. One of these, Sp100, is expressed from a single-copy gene and spliced into four isoforms (A, B, C, and HMG), which differentially regulate transcription. Here we evaluate Sp100 function in single cells using an inducible cytomegalovirus-promoter–regulated transgene, visualized as a chromatinized transcription site. Sp100A is the isoform most strongly recruited to the transgene array, and it significantly increases chromatin decondensation. However, Sp100A cannot overcome Daxx- and α-thalassemia mental retardation, X-linked (ATRX)–mediated transcriptional repression, which indicates that PML-NB/ND10 factors function within a regulatory hierarchy. Sp100A increases and Sp100B, which contains a SAND domain, decreases acetyl-lysine regulatory factor levels at activated sites, suggesting that Sp100 isoforms differentially regulate transcription by modulating lysine acetylation. In contrast to Daxx, ATRX, and PML, Sp100 is recruited to activated arrays in cells expressing the herpes simplex virus type 1 E3 ubiquitin ligase, ICP0, which degrades all Sp100 isoforms except unsumoylated Sp100A. The recruitment Sp100A(K297R), which cannot be sumoylated, further suggests that sumoylation plays an important role in regulating Sp100 isoform levels at transcription sites. This study provides insight into the ways in which viruses may modulate Sp100 to promote their replication cycles.
Progesterone receptor isoforms PRA and PRB differentially contribute to breast cancer cell migration through interaction with focal adhesion kinase complexes
Authors: Bellance Catherine , Khan Junaid A. , Meduri Geri , Guiochon-Mantel Anne , Lombès Marc , Loosfelt Hugues
Published: March 2013

Progesterone receptor (PR) and progestins affect mammary tumorigenesis; however, the relative contributions of PR isoforms A and B (PRA and PRB, respectively) in cancer cell migration remains elusive. By using a bi-inducible MDA-MB-231 breast cancer cell line expressing PRA and/or PRB, we analyzed the effect of conditional PR isoform expression. Surprisingly, unliganded PRB but not PRA strongly enhanced cell migration as compared with PR(–) cells. 17,21-Dimethyl-19-norpregna-4,9-dien-3,20-dione (R5020) progestin limited this effect and was counteracted by the antagonist 11β-(4-dimethyl­amino)­phenyl-17β-hydroxy-17-(1-propynyl)­estra-4,9-dien-3-one (RU486). Of importance, PRA coexpression potentiated PRB-mediated migration, whereas PRA alone was ineffective. PR isoforms differentially regulated expressions of major players of cell migration, such as urokinase plasminogen activator (uPA), its inhibitor plasminogen activator inhibitor type 1, uPA receptor (uPAR), and β1-integrin, which affect focal adhesion kinase (FAK) signaling. Moreover, unliganded PRB but not PRA enhanced FAK Tyr397 phosphorylation and colocalized with activated FAK in cell protrusions. Because PRB, as well as PRA, coimmunoprecipitated with FAK, both isoforms can interact with FAK complexes, depending on their respective nucleocytoplasmic trafficking. In addition, FAK degradation was coupled to R5020-dependent turnovers of PRA and PRB. Such an effect of PRB/PRA expression on FAK signaling might thus affect adhesion/motility, underscoring the implication of PR isoforms in breast cancer invasiveness and metastatic evolution with underlying therapeutic outcomes.
Measurements of forces produced by the mitotic spindle using optical tweezers
Authors: Ferraro-Gideon Jessica , Sheykhani Rozhan , Zhu Qingyuan , Duquette Michelle L. , Berns Michael W. , Forer Arthur
Published: March 2013

We used a trapping laser to stop chromosome movements in Mesostoma and crane-fly spermatocytes and inward movements of spindle poles after laser cuts across Potorous tridactylus (rat kangaroo) kidney (PtK2) cell half-spindles. Mesostoma spermatocyte kinetochores execute oscillatory movements to and away from the spindle pole for 1–2 h, so we could trap kinetochores multiple times in the same spermatocyte. The trap was focused to a single point using a 63× oil immersion objective. Trap powers of 15–23 mW caused kinetochore oscillations to stop or decrease. Kinetochore oscillations resumed when the trap was released. In crane-fly spermatocytes trap powers of 56–85 mW stopped or slowed poleward chromosome movement. In PtK2 cells 8-mW trap power stopped the spindle pole from moving toward the equator. Forces in the traps were calculated using the equation F = Q′P/c, where P is the laser power and c is the speed of light. Use of appropriate Q′ coefficients gave the forces for stopping pole movements as 0.3–2.3 pN and for stopping chromosome movements in Mesostoma spermatocytes and crane-fly spermatocytes as 2–3 and 6–10 pN, respectively. These forces are close to theoretical calculations of forces causing chromosome movements but 100 times lower than the 700 pN measured previously in grasshopper spermatocytes.
First Report of Rice stripe virus in Vietnam
Authors: Ren C. M. , Cheng Z. B. , Miao Q. , Fan Y. J. , Zhou Y. J.
Published: March 2013

Rice stripe virus (RSV) is the type member of the genus Tenuivirus, and one of the prevalent viruses infecting rice. The disease was first recorded in central Japan in 1903, and is currently present in many Asian countries, including South Korea and China in the Far East (1,2). In May of 2012, a disease outbreak in Indica rice (Oryza satira L.) caused losses in a field in Huaifu, Hungyen, Vietnam (20°53′N, 106°02′E). Infected plants showed yellowing stripe symptoms on leaves. A survey indicated that disease incidence was about 10%. Six leaf samples were randomly collected and four were found positive in dot-ELISA using RSV-specific monoclonal antibodies (provided by Dr. X. Zhou, Institute of Biotechnology, Zhejiang University) (3). To confirm RSV infection, total RNA was extracted from dot-ELISA positive and asymptomatic control samples. RT-PCR was performed using RSV-specific primers (CP(+): 5′-GAGGATCCATGGGTACCAACAAGCCAG-3′, CP(-): 5′-TCGTCGACCTAGTCATCTGCACCTTCTG-3′; SP(+): 5′-TGGGATCCATGCAAGACGTACAAAGGAC-3′, SP(-): 5′-CTGTCGACCTATGTTTTATGAAGAAGAGGT-3′; NS2(+): 5′-GAGGATCCATGGGTACCAACAAGCCAG-3′, NS2(-): 5′-CCGTCGACTCATACATCTGAATTTG-3′; NS3(+): 5′-ACCGGATCCATGACTATCAAATACAAC-3′, NS3(-): 5′-CCGTCGACTCATACATTAGCTATTGTC-3′) that amplify the coat protein, disease-specific protein, and NS2 and NS3 genes of RSV, respectively. Amplicons of the expected size were obtained from the four symptomatic but not the asymptomatic plants. Amplicons obtained from one of the positive samples were cloned into the vector pMD18-T (TaKaRa, Dalian, China) and sequenced (GenBank Accession Nos. KC197055 to KC197058). Sequence comparisons indicated that the complete sequences of the CP, SP, NS2, and NS3 of the Vietnamese isolate shared 97.1%, 97.5%, 96.8%, and 97.3% sequence identity at the nucleotide level with the corresponding genes of RSV isolate T (NC_003776, NC_003753, and NC_003754, respectively). These results indicate that the virus associated with yellowing stripe disease of rice in Vietnam is an isolate of RSV. To our knowledge, this is the first report of RSV in Vietnam. This finding redefined the distribution of RSV in the world. Research on whole-genome sequencing of the Vietnamese isolate is continuing and is being expanded to compare the genetic diversity of the virus, assisting in the study of the evolution of the virus.

References: (1) S. Toriyama. Microbiol. Sci. 3:347, 1986. (2) Q. Y. Lin et al. J. Fujian. Agric. Univ. 20:24, 1991. (3) G. Z. Wang et al. Acta Phytopathol. Sinica 34:302, 2004.
First Report of a Chaetomella sp. Causing a Leaf Spot on Sansevieria trifasciata in China
Authors: Li Y. L. , Zhou Z. , Lu W. , Ye J. R.
Published: March 2013

Sansevieria trifasciata originates from tropical West Africa. It is widely planted as a potted ornamental in China for improving indoor air quality (1). In February 2011, leaves of S. trifasciata plants in an ornamental market of Anle, Luoyang City, China, were observed with sunken brown lesions up to 20 mm in diameter, and with black pycnidia present in the lesions. One hundred potted plants were examined, with disease incidence at 20%. The symptomatic leaves affected the ornamental value of the plants. A section of leaf tissue from the periphery of two lesions from a plant was cut into 1 cm2 pieces, soaked in 70% ethanol for 30 s, sterilized with 0.1% HgCl2 for 2 min, then washed five times in sterilized distilled water. The pieces were incubated at 28°C on potato dextrose agar (PDA). Colonies of two isolates were brown with submerged hyphae, and aerial mycelium was rare. Abundant and scattered pycnidia were reniform, dark brown, and 200 to 350 × 100 to 250 μm. There were two types of setae on the pycnidia: 1) dark brown setae with inward curved tops, and 2) straight, brown setae. Conidia were hyaline, unicellular, cylindrical, and 3.75 to 6.25 × 1.25 to 2.50 μm. Morphological characteristics suggested the two fungal isolates were a Chaetomella sp. To confirm pathogenicity, six mature leaves of a potted S. trifasciata plant were wounded with a sterile pin after wiping each leaf surface with 70% ethanol and washing each leaf with sterilized distilled water three times. A 0.5 cm mycelial disk cut from the margin of a 5-day-old colony on a PDA plate was placed on each pin-wounded leaf, ensuring that the mycelium was in contact with the wound. Non-colonized PDA discs were placed on pin-wounded leaves as the control treatment. Each of two fungal isolates was inoculated on two leaves, and the control treatment was done similarly on two leaves. The inoculated plant was placed in a growth chamber at 28°C with 80% relative humidity. After 7 days, inoculated leaves produced brown lesions with black pycnidia, but no symptoms developed on the control leaves. A Chaetomella sp. was reisolated from the lesions of inoculated leaves, but not from the control leaves. An additional two potted plants were inoculated using the same methods as replications of the experiment, with identical results. To confirm the fungal identification, the internal transcribed spacer (ITS) region of rDNA of the two isolates was amplified using primers ITS1 and ITS4 (2) and sequenced. The sequences were identical (GenBank Accession No. KC515097) and exhibited 99% nucleotide identity to the ITS sequence of an isolate of Chaetomella sp. in GenBank (AJ301961). To our knowledge, this is the first report of a leaf spot of S. trifasciata caused by Chaetomella sp. in China as well as anywhere in the world.

References: (1) X. Z. Guo et al. Subtropical Crops Commun. Zhejiang 27:9, 2005. (2) T. J. White et al. PCR Protocols: A Guide to Methods and Applications. M. A. Innis et al., eds. Academic Press, San Diego, CA, 1990.
A Study of Weeds as Potential Inoculum Sources for a Tomato-Infecting Begomovirus in Central Brazil
Authors: Barreto S. S. , Hallwass M. , Aquino O. M. , Inoue-Nagata A. K.
Published: March 2013

Tomato severe rugose virus (ToSRV) is the most important begomovirus species in Brazilian tomato production. Many weeds are associated with tomato, and some are hosts of begomoviruses. Only one species of weed, Nicandra physaloides, has been found to be infected with ToSRV. In this study, four weed species were investigated for their capacity to be infected by ToSRV and serve as a potential source of inoculum for tomato. Begomoviruses from naturally infected Crotalaria spp., Euphorbia heterophylla, N. physaloides, and Sida spp. were successfully transferred to tomato plants by biolistic inoculation. ToSRV was the major virus transferred to tomato. In contrast, other begomoviruses were transferred to weeds, such as Sida micrantha mosaic virus and Euphorbia yellow mosaic virus. Furthermore, a new strain of Sida micrantha mosaic virus is reported. We also confirmed that Crotalaria spp., E. heterophylla, and Sida spp. are infected with ToSRV but at low viral titers and in mixed infections with weed-infecting begomoviruses. Thus, it was demonstrated that weeds are potential sources of ToSRV for tomato in central Brazil.
The pentachlorophenol-dehalogenatingDesulfitobacterium hafniensestrain PCP-1
Authors: Villemur Richard
Published: March 2013

In this report, a complete description ofDesulfitobacterium hafniensestrain PCP-1 is presented. TheD. hafniensestrain PCP-1 was isolated from a methanogenic consortium for its capacity to dehalogenate pentachlorophenol (PCP) into 3-chlorophenol. This strain is also capable of dehalogenating several other chloroaromatic compounds and tetrachloroethene into trichloroethene. Four gene loci encoding putative chlorophenol-reductive dehalogenases (CprA2 to CprA5) were detected, and the products of two of these loci have been demonstrated to dechlorinate different chlorinated phenols. Strain PCP-1 was used in laboratory-scale bioprocesses to degrade PCP present in contaminated environments.Desulfitobacterium hafniensePCP-1 is an excellent candidate for the development of efficient bioprocesses to degrade organohalide compounds.