bluuebunny/crossref_metadata_2025 huggingface dataset:
Humanism of the Nigerian womanist: a cultural appraisal of Femi Osofisan’s Tegonni: an African Antigone
Authors: Odi Christine
Published: March 2018

The evolution of global societies in this age is taking alarmingly negative turns that seem to be catapulting the world into inevitable self-destruction. The incessant violence, terror, horror, disease and deprivation that have enveloped most societies in the world bear testimony to that. Within the Cultural context of the Nigerian worldview human life used to be greatly valued above all else. In contemporary times, human life is fast becoming worthless and cultural values meaningless. Against this bleak global reality, this essay attempts to examine Femi Osofisan’s portraiture of Tegoni and the humanist ideals that he endows her with. The essay investigated the motivational force behind the actions she takes, the consequences of her actions in the throes of the cultural clash prevalent in her society at the time, and her inordinately firm resolve to take full responsibility for her decisions and actions in the face of certain death. The essay’s conclusions revealed that the true Nigerian Womanist as exemplified by Tegoni and a host of other Womanist heroines, will against all odds, strive to nurture and preserve human life and accord it, at all times, the respect, esteem and dignity it deserves in a world where the worth of the human life has become inconsequential.
The Open Global Glacier Model (OGGM) v1.0
Authors: Maussion Fabien , Butenko Anton , Eis Julia , Fourteau Kévin , Jarosch Alexander H. , Landmann Johannes , Oesterle Felix , Recinos Beatriz , Rothenpieler Timo , Vlug Anouk , Wild Christian T. , Marzeion Ben
Published: March 2018

Abstract. Despite of their importance for sea-level rise, seasonal water availability, and as source of geohazards, mountain glaciers are one of the few remaining sub-systems of the global climate system for which no globally applicable, open source, community-driven model exists. Here we present the Open Global Glacier Model (OGGM, http://www.oggm.org), developed to provide a modular and open source numerical model framework for simulating past and future change of any glacier in the world. The modelling chain comprises data downloading tools (glacier outlines, topography, climate, validation data), a preprocessing module, a mass-balance model, a distributed ice thickness estimation model, and an ice flow model. The monthly mass-balance is obtained from gridded climate data and a temperature index melt model. To our knowledge, OGGM is the first global model explicitly simulating glacier dynamics: the model relies on the shallow ice approximation to compute the depth-integrated flux of ice along multiple connected flowlines. In this paper, we describe and illustrate each processing step by applying the model to a selection of glaciers before running global simulations under idealized climate forcings. Even without an in-depth calibration, the model shows a very realistic behaviour. We are able to reproduce earlier estimates of global glacier volume by varying the ice dynamical parameters within a range of plausible values. At the same time, the increased complexity of OGGM compared to other prevalent global glacier models comes at a reasonable computational cost: several dozens of glaciers can be simulated on a personal computer, while global simulations realized in a supercomputing environment take up to a few hours per century. Thanks to the modular framework, modules of various complexity can be added to the codebase, allowing to run new kinds of model intercomparisons in a controlled environment. Future developments will add new physical processes to the model as well as tools to calibrate the model in a more comprehensive way. OGGM spans a wide range of applications, from ice-climate interaction studies at millenial time scales to estimates of the contribution of glaciers to past and future sea-level change. It has the potential to become a self-sustained, community driven model for global and regional glacier evolution.
Improving soil moisture and runoff simulations over Europe using a
high-resolution data-assimilation modeling framework
Authors: Naz Bibi S. , Kurtz Wolfgang , Montzka Carsten , Sharples Wendy , Goergen Klaus , Keune Jessica , Gao Huilin , Springer Anne , Hendricks Franssen Harrie-Jan , Kollet Stefan
Published: March 2018

Abstract. Accurate and reliable hydrologic simulations are important for many applications such as water resources management, future water availability projections and predictions of extreme events. However, the accuracy of water balance estimates is limited by the lack of observations at large scales and the uncertainties of model simulations due to errors in model structure and inputs (e.g. hydrologic parameters and atmospheric forcings). In this study, we assimilated ESA CCI soil moisture (SM) information to improve the estimation of continental-scale soil moisture and runoff. The assimilation experiment was conducted over a time period from 2000 to 2006 with the Community Land Model, version 3.5 (CLM3.5) integrated with the Parallel Data Assimilation Framework (PDAF) at spatial resolution of 0.0275° (~ 3 km) over Europe. The model was forced with the high-resolution reanalysis COSMO-REA6 from the Hans-Ertel Centre for Weather Research (HErZ). Our results show that estimates of soil moisture have improved, particularly in the summer and autumn seasons when cross-validated with independent CCI-SM observations. On average, the mean bias in soil moisture was reduced from 0.1 mm3/mm3 in open-loop simulations to 0.004 mm3/mm3 with SM assimilation. The assimilation experiment also shows overall improvements in runoff, particularly during peak runoff. The results demonstrate the potential of assimilating satellite soil moisture observations to improve high-resolution soil moisture and runoff simulations at the continental scale, which is useful for water resources assessment and monitoring.
Application of ensemble transform data assimilation methods for
parameter estimation in nonlinear problems
Authors: Ruchi Sangeetika , Dubinkina Svetlana
Published: March 2018

Abstract. Over the years data assimilation methods have been developed to obtain estimations of uncertain model parameters by taking into account a few observations of a model state. However, most of these computationally affordable methods have assumptions of Gaussianity, e.g. an Ensemble Kalman Filter. Ensemble Transform Particle Filter does not have the assumption of Gaussianity and has proven to be highly beneficial for an initial condition estimation and a small number of parameter estimation in chaotic dynamical systems with non-Gaussian distributions. In this paper we employ Ensemble Transform Particle Smoother (ETPS) and Ensemble Transform Kalman Smoother (ETKS) for parameter estimation in nonlinear problems with 1, 5, and 2500 uncertain parameters and compare them to importance sampling (IS). We prove that the updated parameters obtained by ETPS lie within the range of an initial ensemble, which is not the case for ETKS. We examine the performance of ETPS and ETKS in a twin experiment setup, where observations of pressure are synthetically created based on the know values of parameters. The numerical experiments demonstrate that the ETKS provides good estimations of the mean parameters but not of the posterior distributions and as the ensemble size increases the posterior does not improve. ETPS provides good approximations of the posterior and as the ensemble size increases the posterior converges to the posterior obtained by IS with a large ensemble. ETKS is very robust while ETPS is very sensitive with respect to the initial ensemble. An issue of an increase in the root mean square error after data assimilation is performed in ETPS for a high-dimensional test problem is resolved by applying distance-based localization, which however deteriorated the posterior estimation.
Changes in Andes snow cover from MODIS data, 2000–2016
Authors: Saavedra Freddy A. , Kampf Stephanie K. , Fassnacht Steven R. , Sibold Jason S.
Published: March 2018

Abstract. The Andes span a length of 7000 km and are important for sustaining regional
water supplies. Snow variability across this region has not been studied in
detail due to sparse and unevenly distributed instrumental climate data. We
calculated snow persistence (SP) as the fraction of time with snow cover for
each year between 2000 and 2016 from Moderate Resolution Imaging
Spectroradiometer (MODIS) satellite sensors (500 m, 8-day maximum snow cover
extent). This analysis is conducted between 8 and 36∘ S due to high
frequency of cloud (> 30 % of the time) south and north of this range.
We ran Mann–Kendall and Theil–Sens analyses to identify areas with
significant changes in SP and snowline (the line at lower elevation where
SP = 20 %). We evaluated how these trends relate to temperature and
precipitation from Modern-Era Retrospective Analysis for Research and
Applications-2 (MERRA2) and University of Delaware datasets and climate
indices as El Niño–Southern Oscillation (ENSO), Southern Annular Mode
(SAM), and Pacific Decadal Oscillation (PDO). Areas north of 29∘ S
have limited snow cover, and few trends in snow persistence were detected. A
large area (34 370 km2) with persistent snow cover between 29 and
36∘ S experienced a significant loss of snow cover (2–5 fewer days
of snow year−1). Snow loss was more pronounced (62 % of the area
with significant trends) on the east side of the Andes. We also found a
significant increase in the elevation of the snowline at
10–30 m year−1 south of 29–30∘ S. Decreasing SP correlates
with decreasing precipitation and increasing temperature, and the magnitudes
of these correlations vary with latitude and elevation. ENSO climate indices
better predicted SP conditions north of 31∘ S, whereas the SAM
better predicted SP south of 31∘ S.
Cáncer parental: díptico de soporte para padres y madres recién diagnosticados
Authors: Fuentes Sanmartín Sònia , Barez Villoria Milagros , Caba Vela Lydia , De Cáceres Zurita María Luisa
Published: March 2018

Nota informativa.
Los demás días (Atención domiciliaria en cuidados paliativos)
Authors: Acinas Patricia
Published: March 2018

Los demás días. España. 2017. Director Carlos Agulló. Duración 95’. Pendiente de calificación por edades. Película documental sobre los profesionales de cuidados paliativos.
Nominal structure in a language without articles: The case of Estonian
Authors: Norris Mark
Published: March 2018

It is standardly assumed that nominals in the languages of the world are syntactically complex in the typical case, being made up of not just NP, but one or more functional projections, e.g., DP (Abney 1987). Recently, this assumption has been questioned, especially for languages without articles (Bošković 2005, et seq.). The alternative proposal holds that nominals in Serbo-Croatian (and more strongly, languages without articles in general) lack the DP projection, and that this difference has a variety of syntactic consequences. In this paper, I investigate the nominal extended projection of another language without articles, Estonian (Finno-Ugric). On the basis of a number of facts about Estonian’s system of adnominal genitives, I conclude that nominals in Estonian should not be given the same analysis as those in Serbo-Croatian. I propose instead that Estonian’s nominals are DPs. I then propose that indefinite pronouns and wh-determiners instantiate the category D0 in the language, arguing that DP does more cross-linguistically than host articles. I conclude that nominal structure in languages without articles can be just as complex as nominal structure in languages with articles.
Auditory disruption improves word segmentation: A functional basis for lenition phenomena
Authors: Katz Jonah , Fricke Melinda
Published: March 2018

This paper presents evidence that spirantization, a cross-linguistically common lenition process, affects English listeners’ ease of segmenting novel “words” in an artificial language. The cross-linguistically common spirantization pattern of initial stops and medial continuants (e.g. [ɡuβa]) results in improved word segmentation compared to the inverse “anti-lenition” pattern of initial continuants and medial stops (e.g. [ɣuba]). The study also tests the effect of obstruent voicing, another common lenition pattern, but finds no significant differences in segmentation performance. There are several points of broader interest in these studies. Most of the phonetic factors influencing word segmentation in past studies have been language-specific and/or prosodic in nature: stress, intonation, final lengthening, etc. Spirantization, while often prosodically conditioned, is different from all of these patterns in that it concerns a segmental alternation. Moreover, the effects reported here are for speakers of a language, American English, that only sporadically displays spirantization, and not in the phonological contexts used in the experiment. This suggests that the results may reflect more general properties of speech perception and word boundary detection, rather than a perceptual processing strategy transferred directly from English. As such, the studies offer partial support for theories of lenition rooted in notions of perceptual-acoustic continuity and disruption.
Cálculo da Probabilidade e Quantificação do Volume de Material Suscetível a Escorregamentos - Bacia do Rio Jacareí, Morretes - PR
Authors: Folador Rodrigo Marques , Silveira Claudinei Taborda , Fiori Alberto Pio
Published: March 2018

Em 2011, nos municípios de Morretes e Paranaguá, ocorreram grandes movimentos de massa que foram estudados para entender os processos e gerar os produtos que auxiliassem na prevenção de tais catástrofes. Este trabalho aplica uma metodologia para quantificar o volume de material suscetível a escorregamentos, através de um método que sirva de auxílio na prevenção de movimentos de massa. A quantificação do volume de massa movimentada é determinada a partir do cálculo da probabilidade de ocorrência dos escorregamentos. Foi gerado em ambiente SIG um modelo digital de elevação e a partir deste realizados os processamentos dos atributos topográficos, utilizados para atribuir valores a um mapa de solos por meio de álgebra de mapas. Deste mapa foram extraídos os parâmetros físicos do solo, através de ensaios de cisalhamento direto e de análises de trabalhos anteriores, aplicados no cálculo do Fator de Segurança realizado em ferramenta SIG, que possibilitou calcular equações aplicadas a grids espacializadas. Para o cálculo da probabilidade de escorregamentos, foi utilizado o desvio padrão do Fator de Segurança. O volume de solo desmoronado é dado pelo produto da área da cunha instável de solo, pelo comprimento linear da porção propensa ao desmoronamento, estimado pela probabilidade encontrada. Como resultados, foi possível observar os principais focos de risco na área da bacia, nos relevos mais acidentados. Calculado o desvio padrão do Fator de Segurança, foram obtidos os valores do coeficiente de segurança e reclassificados com base em uma tabela de distribuição normal, resultando na probabilidade. Os valores mostraram áreas com alta probabilidade principalmente ao Sul da bacia. A partir dos valores encontrados, as áreas mais suscetíveis foram separadas por classes referentes às probabilidades determinadas e posteriormente utilizadas para o cálculo do volume de material suscetível a escorregamentos.
The Right to Same-Sex Marriage: Assessing the European Court of Human Rights’ Consensus-Based Analysis in Recent Judgments Concerning Equal Marriage Rights
Authors: Shahid Masuma
Published: March 2018

The Right to Same-Sex Marriage: Assessing the European Court of Human Rights’ Consensus-Based Analysis in Recent Judgments Concerning Equal Marriage Rights

This contribution assesses the consensus-based analysis and reasoning of the European Court of Human Rights in recent judgments concerning equal marriage rights and compares it to the Court’s past jurisprudence on European consensus and the margin of appreciation awarded to Member States regarding the issue of equal marriage rights. The contribution aims to analyse whether there is a parallel to be seen between the rapid global trend of legalisation of same-sex marriage and the development or evolution of the case law of the ECtHR on the same topic. Furthermore, it demonstrates that the Court’s consensus-based analysis is problematic for several reasons and provides possible alternative approaches to the balancing of the Court between, on the one hand, protecting rights of minorities (in this case same-sex couples invoking equal marriage rights) under the European Convention on Human Rights and, on the other hand, maintaining its credibility, authority and legitimacy towards Member States that might disapprove of the evolving case law in the context of same-sex relationships. It also offers insights as to the future of European consensus in the context of equal marriage rights and ends with some concluding remarks.
Inf3switch
Authors: User Crossref
Published: March 2018

TEST
Désir, conditions et politiques de reconnaissance du chercheur en sciences sociales : réflexions sur la performance de terrain et d’écriture
Authors: Bétrisey Florence
Published: March 2018

Dans cet article, nous proposons d’analyser la démarche de recherche et le comportement des sujets-chercheurs au prisme de la notion de reconnaissance. Nous questionnons notre propre démarche et notre propre comportement de sujet-chercheuse dans le cadre de notre recherche doctorale en Bolivie. Plus particulièrement, nous analysons deux dimensions clés de la recherche en sciences sociales : la performance du travail de terrain et l’espace académique (eurocentriste) dans lequel s’inscrit le chercheur.

L’analyse du travail de terrain (compris comme une performance sociale) au prisme de la notion de reconnaissance nous permet d’abord d’éclairer les tensions entre conformisme stratégique du chercheur et reproduction de normes sociales locales. Dans un deuxième temps, nous mettons en évidence le désir du chercheur d’obtenir une reconnaissance académique et la façon dont ce désir l’enjoint à reproduire la grammaire dominante de reconnaissance académique. Nous éclairons notamment le fait que ce désir d’obtention d’une reconnaissance, sociale ou académique est étroitement lié aux relations de pouvoir qui structurent l’espace académique (lequel n’est, au demeurant, pas considéré comme un espace neutre).

Enfin, nous montrons que, si la promesse de reconnaissance rend la contestation des normes de reconnaissance difficile, elle n’empêche pas leur contournement, par exemple par l’adhésion à des récits alternatifs de la qualité de la recherche (« slow science »). Ces derniers peuvent en effet agir comme des canaux alternatifs de reconnaissance, producteurs de nouveaux récits et nouvelles grammaires de reconnaissance. Or ces mécanismes de conformisme, résistance ou contournement des normes de reconnaissance, autant en ce qui concerne la performance de terrain que l’espace académique, se déroulent souvent dans le domaine de l’inconscient et du non cognitif.
De la désaffiliation du chercheur pour l’élaboration des connaissances : comment se positionner en tant que chercheur et acteur dans une école ethno-religieuse?
Authors: Essid Souheil , Essid Hamas Yosra
Published: March 2018

Quand le chercheur s’investit dans son action de recherche, il entretient un rapport cognitif et affectif avec son objet d’étude. Dans cet article, nous souhaitons aborder comment la question de l’implication du chercheur est un enjeu de la recherche et en quoi l’analyse des processus à l’oeuvre pour le chercheur peut devenir un objet de réflexion qui permet aussi une compréhension de l’objet d’étude. Dans le cadre d’une recherche doctorale sur le rôle de la religion et de l’école dans la construction identitaire des jeunes, notre immersion dans une école primaire au Québec nous place au coeur d’un processus réflexif sur la posture du chercheur, sur sa réflexivité et sur son positionnement par rapport à soi-même, à ses sujets de recherche et à ses outils de collecte de données. Dans cette étude, l’observation ethnographique comme outil de collecte de données nous a placé au coeur d’un processus conversationnel continu avec les sujets, avec les données et avec soi-même. Le processus a conduit le chercheur à une désaffiliation religieuse et à une réflexion sur les aspects intersubjectifs de la recherche.
La encapsulación nominal en el discurso académico-científico oral y escrito: patrones de aparición
Authors: López Samaniego Anna
Published: March 2018

Este artículo analiza el funcionamiento de los encapsuladores nominales infieles en un corpus de discurso académico-científico en español formado por comunicaciones orales sobre lingüística presentadas en congresos y los artículos de investigación correspondientes publicados en revistas científicas o en actas de congreso (102 903 palabras). Se denomina encapsulador nominal infiel a aquel sustantivo que condensa el contenido de una o más predicaciones del discurso circundante y lo categoriza en tanto que entidad discursiva. Este mecanismo aparece habitualmente en patrones léxico-gramaticales como el patrón nominal especificativo (el hecho de que…), el patrón atributivo especificativo (el hecho es que…), o en patrones discursivos como el patrón atributivo anafórico, el patrón remático, el patrón temático y el patrón de marco interpretativo. Este trabajo se propone analizar las funciones y la frecuencia de aparición de estos patrones en dos modos de comunicación, oral y escrito. Los resultados del análisis muestran, de un lado, que la mayoría de estos patrones parecen ser más propios de alguna de estas dos modalidades y, además, que algunos encapsuladores presentan un grado considerable de atracción hacia ciertos patrones, lo cual constituye una prueba más de la estrecha relación existente entre léxico y gramática discursiva.
Los encapsuladores anafóricos: una propuesta de clasificación
Authors: Borreguero Zuloaga Margarita
Published: March 2018

En este trabajo se define desde un punto de vista formal, semántico e informativo un tipo de sintagmas nominales encapsuladores. Se trata de sintagmas nominales con un componente anafórico que reifican y recategorizan fragmentos discursivos para convertirlos en puntos de anclaje informativos (temas) a partir de los cuales poder desarrollar el discurso. Son los llamados encapsuladores anafóricos (temáticos). Se propone asimismo una clasificación de los tipos de sintagmas que pueden desempeñar esta función discursiva, atendiendo a 3 parámetros: (a) la naturaleza léxico-semántica del núcleo nominal; (b) la presencia o ausencia de componentes axiológicos en el sintagma, y (c) el elemento sintagmático portador de dicho componente. Se pretende de este modo sistematizar en una única taxonomía los distintos tipos de encapsuladores, que bajo distintas funciones, han sido analizados en la bibliografía, siempre y cuando presenten las características formales e informativas descritas.
Estructures encapsuladores amb valor metadiscursiu en el debat parlamentari
Authors: Marín i Jordà Maria Josep , Ribera i Condomina Josep E.
Published: March 2018

L’encapsulació per mitjà de noms abstractes i inespecífics (com ara conclusió, tema, realitat o problema) permet reïficar fragments discursius complexos de naturalesa predicativa i conceptualitzar-los semànticament. Així, els encapsuladors o shell nouns (Schmid 2000) constitueixen una classe funcional privilegiada per a delimitar l’estructura organitzativa de gèneres formals i mostren la vinculació entre encapsulació i metadiscurs. A partir d’un corpus de debat parlamentari en català, espanyol i anglès, i del marc teòric sobre el metadiscurs proporcionat per Hyland (2004) i Hyland & Tse (2005), aquest treball analitza la funció metadiscursiva de certes estructures amb encapsulador que reflecteixen com l’emissor organitza el discurs i interactua amb el potencial receptor. L’anàlisi d’aquestes estructures, amb graus de fixació diversos, permet establir cinc classes més o menys homogènies en les tres llengües: organitzadors textuals, adjunts oracionals, connectors lèxics (Cuenca 1998), locucions modals i dos patrons copulatius. Les classes es descriuen funcionalment, formalment i discursivament, mostrant com es vinculen al vessant textual o interpersonal del metadiscurs i sense obviar els límits difusos entre ambdues funcions.
Laure Sarda, Denis Vigier & Bernard Combettes (dir.), «Connexion et indexation. Ces liens qui tissen le texte», Lió, Ens Éditions, 2016, 224 pp.
Authors: Besa Camprubí Josep
Published: March 2018

Ressenya sobre el llibre de Laure Sarda, Denis Vigier & Bernard Combettes (dir.), «Connexion et indexation. Ces liens qui tissen le texte», Lió, Ens Éditions, 2016, 224 pp., ISBN: 978-2-84788-798-3.
Pere Ballart, Jordi Malé, Marcel Ortín, Joaquim Espinós & Gonçal López-Pampló, «Joan Fuster i la ironia», València, PUV, 2017, 162 pp.
Authors: Ferrando Mireia
Published: March 2018

Ressenya sobre el llibre de Pere Ballart, Jordi Malé, Marcel Ortín, Joaquim Espinós & Gonçal López-Pampló, «Joan Fuster i la ironia», València, Publicacions de la Universitat de València, 2017, 162 pp., ISBN: 978-84-9134-008-9.
Vicent Beltran Calvo & Carles Segura-Llopes, «Els parlars valencians», València, PUV, 2017, 400 pp.
Authors: Martí Mestre Joaquim
Published: March 2018

Ressenya sobre el llibre de Vicent Beltran Calvo & Carles Segura-Llopes, «Els parlars valencians», València, Publicacions de la Universitat de València («Biblioteca Lingüística Catalana», 34), 2017, 400 pp., ISBN: 978-84-9134-010-2.
The role of subnational governments in addressing ocean health and diversity in a time of global change
Authors: Zivian Anna M
Published: March 2018

Threats to marine biodiversity are increasing, from overfishing to seismic activity to nutrient pollution. The ocean is warming and acidifying, dissolved oxygen is decreasing, and global mean sea level is rising as sea ice melts. Even with a new global focus on the ocean and a goal of reducing emissions faster and sooner, there will be centuries of lag time in the ocean’s response to greenhouse gases. We are already seeing the effects of individual climate stressors, including accelerated loss of sea ice, changes in ocean currents, coral bleaching, and coastal erosion. We are thus faced with dual problems of mitigating and adapting to climate change, but political action remains difficult due to ongoing uncertainty and partisan conflict. As governance issues become more complex and more difficult, local government is proving to be a place where people are actively implementing solutions, and a place where citizenscan make their voices heard and effect change. Growing examples of this in the ocean realm include subnational creation of Marine Protected Areas, local policies to reduce marine debris, and leadership in climate fora from the International Alliance to Combat Ocean Acidification to C40 Cities. This presentation reviews subnational engagement and suggests paths forward for improved ocean governance.
PromoterPredict: sequence-based modelling of Escherichia coli σ70 promoter strength yields logarithmic dependence between promoter strength and sequence
Authors: Bharanikumar Ramit , R Premkumar Keshav Aditya , Palaniappan Ashok
Published: March 2018

We present PromoterPredict, a dynamic multiple regression approach to predict the strength of Escherichia coli promoters binding the σ70 factor of RNA polymerase. σ70 promoters are ubiquitously used in recombinant DNA technology, but characterizing their strength is demanding in terms of both time and money. Using a well-characterized set of promoters, we trained a multivariate linear regression model and found that the log of the promoter strength is significantly linearly associated with a weighted sum of the –10 and –35 sequence profile scores. It was found that the two regions contributed almost equally to the promoter strength. PromoterPredict accepts –10 and –35 hexamer sequences and returns the predicted promoter strength. It is capable of dynamic learning from user-supplied data to refine the model construction and yield more confident estimates of promoter strength.
Agronomical, biochemical and histological response of resistant and susceptible wheat and barley under BYDV stress
Authors: Choudhury Shormin , Hu Hongliang , Larkin Philip , Meinke Holger , Shabala Sergey , Ahmed Ibrahim , Zhou Meixue
Published: March 2018

Barley yellow dwarf virus-PAV (BYDV-PAV) is one of the major viruses causing a widespread and serious viral disease affecting cereal crops. To gain a better understanding of plant defence mechanisms of BYDV resistance genes ( Bdv2 and Yd2 ) against BYDV-PAV infection, the differences in agronomical, biochemical and histological changes between susceptible and resistant wheat and barley cultivars were investigated. We found that root growth and total dry matter of susceptible cultivars showed greater reduction than that of resistant ones after infection. BYDV infected leaves in susceptible wheat and barley cultivars showed a significant reduction in photosynthetic pigments, an increase in the concentration of reducing sugar. The protein levels were also low in infected leaves. There was a significant increase in total phenol contents in resistant cultivars, which might reflect a protective mechanism of plants against virus infection. In phloem tissue, sieve elements (SE) and companion cells (CC) were severely damaged in susceptible cultivars after infection. It is suggested that restriction of viral movement in the phloem tissue and increased production of phenolic compounds may play a role in the resistance and defensive mechanisms of both Bdv2 and Yd2 against virus infection.
Regional environmental conditions determine tolerance to future warming of a marine macroalgae forests
Authors: Verdura Jana , de Caralt Sonia , Santamaria Jorge , Vergés Alba , Mangialajo Luisa , Ivesa Ljiljana , Farina Simone , Cefalí Maria Elena , Fraschetti Simonetta , Ballesteros Enric , Cebrian Emma
Published: March 2018

Abstract: In the Mediterranean Sea, many species of Cystoseira, which are important habitat-forming species on shallow rocky bottoms, have gone missing from many coastal areas, impairing essential ecosystem services. Cystoseira crinita forests thrive in very shallow waters from sheltered environments and are currently regressing in several European shores. In the actual scenario of ocean warming it is essential to determine the vulnerability of these populations to thermal stress in order to design future conservation actions. Since the response of this macroalgae to thermal stress may be site-specific, here we compared the thermal tolerance of populations dwelling in the coldest and warmest areas of the Mediterranean Sea. We show that C. crinita populations from warmer areas (Eastern Mediterranean) had a temperature tolerance threshold 2ºC higher than Northwestern Mediterranean populations. There is a strong correlation between the observed differential phenotypic responses and the local temperature regimes experienced by each population. This is the first evidence for the role of thermal history in shaping the thermotolerance responses marine habitat-forming macroalgae under contrasting temperature environments. Financial support from EU2020 (R+I) under grant agreement No 689518 (MERCES) and MINECO (CGL2016-76341-R).
The NIH must reduce disparities in funding to maximize its return on investments from taxpayers
Authors: Wahls Wayne P
Published: March 2018

New data from the NIH reveal that the scientific return on its sponsored research reaches a maximum at around $400,000 of annual support per principal investigator. We discuss the implications of this 'sweet spot' for funding policy, and propose that the NIH should limit both the minimum and maximum amount of funding per researcher.
Secretory vesicles of immune cells contain only a limited number of interleukin 6 molecules
Authors: Verboogen Daniëlle R. J. , ter Beest Martin , Honigmann Alf , van den Bogaart Geert
Published: March 2018

Immune cells communicate by releasing large quantities of cytokines. Although the mechanisms of cytokine secretion are increasingly understood, quantitative knowledge of the number of cytokines per vesicle is still lacking. Here, we measured with quantitative microscopy the release rate of vesicles potentially carrying interleukin‐6 (IL‐6) in human dendritic cells. By comparing this to the total secreted IL‐6, we estimate that secretory vesicles contain about 0.5–3 IL‐6 molecules, but with a large spread among cells/donors. Moreover, IL‐6 did not accumulate within most cells, indicating that synthesis and not trafficking is the bottleneck for IL‐6 production. IL‐6 accumulated in the Golgi apparatus only in ~ 10% of the cells. Understanding how immune cells produce cytokines is important for designing new immunomodulatory drugs.
A Potential Link Between Waterfall Recession Rate and Bedrock Channel Concavity
Authors: Shelef Eitan , Haviv Itai , Goren Liran
Published: March 2018

The incision of bedrock channels is typically modeled through the stream power or the shear stress applied on the channel bed. However, this approach is not valid for quasi‐vertical knickpoints (hereafter waterfalls), where water and sediments do not apply direct force on the vertical face. As such, waterfall retreat rate is often modeled as a power function of drainage area (a surrogate for hydraulic processes, such as plunge‐pool drilling and groundwater seepage, although a variety of non‐hydraulic processes may also influence waterfall retreat). These different incision modes are associated with two measurable exponents: the channel concavity, θ, that is measured from the channel topography and is used to evaluate the exponents of drainage area and slope in the channel incision model, and p that is measured from the location of waterfalls within watersheds and evaluates the dependency of the waterfall recession rate on drainage area. To better understand the relations between channel incision and waterfall recession, we systematically compare between the exponents p and θ. These parameters were computed from digital elevation models (30‐m Shuttle Radar Topography Mission) of 12 river basins with easily detectable waterfalls. We show that p and θ are (1) similar within uncertainty, (2) come from a similar distribution, and (3) covary for networks with a large number of waterfalls (
). In the context of bedrock incision models this hints that the same processes govern waterfall retreat rate and the incision of nonvertical channel reaches in the analyzed basins and/or that downstream incision can dictate waterfall retreat rate.
Electron Physics in 3‐D Two‐Fluid 10‐Moment Modeling of Ganymede's Magnetosphere
Authors: Wang Liang , Germaschewski Kai , Hakim Ammar , Dong Chuanfei , Raeder Joachim , Bhattacharjee Amitava
Published: March 2018

We studied the role of electron physics in 3‐D two‐fluid 10‐moment simulation of Ganymede's magnetosphere. The model captures nonideal physics like the Hall effect, electron inertia, and anisotropic, nongyrotropic pressure effects. A series of analyses were carried out: (1) The resulting magnetic field topology and electron and ion convection patterns were investigated. The magnetic fields were shown to agree reasonably well with in situ measurements by the Galileo satellite. (2) The physics of collisionless magnetic reconnection were carefully examined in terms of the current sheet formation and decomposition of generalized Ohm's law. The importance of pressure anisotropy and nongyrotropy in supporting the reconnection electric field is confirmed. (3) We compared surface “brightness” morphology, represented by surface electron and ion pressure contours, with oxygen emission observed by the Hubble Space Telescope. The correlation between the observed emission morphology and spatial variability in electron/ion pressure was demonstrated. Potential extension to multi‐ion species in the context of Ganymede and other magnetospheric systems is also discussed.
Estimation of Mesospheric Densities at Low Latitudes Using the Kunming Meteor Radar Together With SABER Temperatures
Authors: Yi Wen , Xue Xianghui , Reid Iain M. , Younger Joel P. , Chen Jinsong , Chen Tingdi , Li Na
Published: March 2018

Neutral mesospheric densities at a low latitude have been derived during April 2011 to December 2014 using data from the Kunming meteor radar in China (25.6°N, 103.8°E). The daily mean density at 90 km was estimated using the ambipolar diffusion coefficients from the meteor radar and temperatures from the Sounding of the Atmosphere using Broadband Emission Radiometry (SABER) instrument. The seasonal variations of the meteor radar‐derived density are consistent with the density from the Mass Spectrometer and Incoherent Scatter (MSIS) model, show a dominant annual variation, with a maximum during winter, and a minimum during summer. A simple linear model was used to separate the effects of atmospheric density and the meteor velocity on the meteor radar peak detection height. We find that a 1 km/s difference in the vertical meteor velocity yields a change of approximately 0.42 km in peak height. The strong correlation between the meteor radar density and the velocity‐corrected peak height indicates that the meteor radar density estimates accurately reflect changes in neutral atmospheric density and that meteor peak detection heights, when adjusted for meteoroid velocity, can serve as a convenient tool for measuring density variations around the mesopause. A comparison of the ambipolar diffusion coefficient and peak height observed simultaneously by two co‐located meteor radars indicates that the relative errors of the daily mean ambipolar diffusion coefficient and peak height should be less than 5% and 6%, respectively, and that the absolute error of the peak height is less than 0.2 km.
Effects of the Non‐breaking Surface Wave‐induced Vertical Mixing on Winter Mixed Layer Depth in Subtropical Regions
Authors: Chen Siyu , Qiao Fangli , Huang Chuanjiang , Song Zhenya
Published: March 2018

Compared to observations, the simulated multi‐model mean surface oceanic mixed layer depth (MLD) during winter in the subtropical regions of both hemispheres shows deep bias from 45 CMIP5 climate models. Our results from two numerical experiments using one of CMIP5 models show that the non‐breaking surface wave‐induced vertical mixing can serve as a remedy. The enhanced vertical mixing increases the heat content of the upper ocean and reduces the oceanic potential density in winter which then stabilize the upper ocean and shallow the simulated winter MLD in subtropical regions. This heat content increase is not directly induced by air‐sea heat fluxes during winter, but is the legacy of temperature increase during summer, when the additional vertical mixing induces an enhanced surface heating. The simulation biases of the annually averaged water temperatures in the upper 400 m reduced by 43% and 28% in south and north latitude bands between 20°and 40°, respectively. The non‐breaking surface wave‐induced vertical mixing shallows both boreal and austral winter MLDs by 2–11 m (a change of 5–20%) in both northern and southern subtropical regions. These results indicate that the incorporation of vertical mixing induced by the non‐breaking surface waves in our experiments can improve the simulation of boreal and austral winter MLDs in northern and southern subtropical regions.
Generation and Propagation of Nonlinear Internal Waves in Sheared Currents Over the Washington Continental Shelf
Authors: Hamann Madeleine M. , Alford Matthew H. , Mickett John B.
Published: March 2018

The generation, propagation, and dissipation of nonlinear internal waves (NLIW) in sheared background currents is examined using 7 days of shipboard microstructure surveys and two moorings on the continental shelf offshore of Washington state. Surveys near the hypothesized generation region show semi‐diurnal (D2) energy flux is onshore and that the ratio of energy flux to group speed times energy (
) increases sharply at the shelf break, suggesting that the incident D2 internal tide is partially reflected and partially transmitted. NLIW appear at an inshore mooring at the leading edge of the onshore phase of the baroclinic tide, consistent with nonlinear transformation of the shoaling internal tide as their generation mechanism. Of the D2 energy flux observed at the eastern extent of the generation region (133 ± 18 Wm−1), approximately 30% goes into the NLIW observed inshore (36 ± 11 Wm−1). Inshore of the moorings, 7 waves are tracked into shallow (30‐40 m) water, where a vertically sheared, southward current becomes strong. As train‐like waves propagate onshore, wave amplitudes of 25‐30 m and energies of 5 MJ decrease to 12 m and 10 kJ, respectively. The observed direction of propagation rotates from
N of E to
S of E in the strongly sheared region. Linear ray tracing using the Taylor‐Goldstein equation to incorporate parallel shear effects accounts for only a small portion of the observed rotation, suggesting that three‐dimensionality of the wave crests and the background currents is important here.
Northward Pathway Across the Tropical North Pacific Ocean Revealed by Surface Salinity: How do El Niño Anomalies Reach Hawaii?
Authors: Hasson Audrey , Puy Martin , Boutin Jacqueline , Guilyardi Eric , Morrow Rosemary
Published: March 2018

Using the unprecedented 7 year monitoring of sea surface salinity (SSS) from the Soil Moisture Ocean Salinity (SMOS) satellite mission, an unexpected large‐scale anomaly at 20°N is studied in the tropical Pacific Ocean following the 2015‐2016 extreme El Niño event. This basin‐wide negative anomaly (below −0.3) is present in October 2015 between 15 and 25°N, reaching the Hawaiian archipelago. It has not been previously observed during El Niño events. It is accompanied by a negative equatorial SSS anomaly at the dateline (below −0.5) which has been previously described as an El Niño‐associated SSS anomaly. A wide range of observations (in situ and space‐borne) and a state‐of‐the‐art ocean model simulation are used together to characterize and understand the mechanisms leading to this singular SSS signal. The extra‐equatorial negative SSS anomaly is found to be a superposition of a persisting SSS anomaly due to the 2014 weak El Niño and of the larger 2015‐2016 El Niño SSS anomaly. Both were advected northward in the tropical current system by the mean Ekman currents and hypothetically by instabilities in the zonal currents patterns. An analysis of analogous structures in the past 20 years shows that this northward displacement of SSS anomalies is not El Niño specific, even if their advection is enhanced during El Niño events. This study shows that when surface freshwater fluxes are weak SSS, unlike sea surface temperature, can be used to trace water mass displacement for up to 20 months.
Mapping Dependence Between Extreme Rainfall and Storm Surge
Authors: Wu Wenyan , McInnes Kathleen , O'Grady Julian , Hoeke Ron , Leonard Michael , Westra Seth
Published: March 2018

Dependence between extreme storm surge and rainfall can have significant implications for flood risk in coastal and estuarine regions. To supplement limited observational records, we use reanalysis surge data from a hydrodynamic model as the basis for dependence mapping, providing information at a resolution of approximately 30 km along the Australian coastline. We evaluated this approach by comparing the dependence estimates from modeled surge to that calculated using historical surge records from 79 tide gauges around Australia. The results show reasonable agreement between the two sets of dependence values, with the exception of lower seasonal variation in the modeled dependence values compared to the observed data, especially at locations where there are multiple processes driving extreme storm surge. This is due to the combined impact of local bathymetry as well as the resolution of the hydrodynamic model and its meteorological inputs. Meteorological drivers were also investigated for different combinations of extreme rainfall and surge—namely rain‐only, surge‐only, and coincident extremes—finding that different synoptic patterns are responsible for each combination. The ability to supplement observational records with high‐resolution modeled surge data enables a much more precise quantification of dependence along the coastline, strengthening the physical basis for assessments of flood risk in coastal regions.
The Remobilization and Removal of Fe in Estuary—A Case Study in the Changjiang Estuary, China
Authors: Zhu Xunchi , Zhang Ruifeng , Wu Ying , Zhu Jianrong , Bao Daoyang , Zhang Jing
Published: March 2018

Dissolved iron (dFe) delivered by rivers plays a vital role in supporting primary productivity in coastal ecosystems. River‐borne Fe is generally removed in estuaries due to the salt‐induced flocculation. However, effects of the river mouth bar area on the variations of dFe concentration are frequently overlooked. Here we show the results of quasi‐synchronous observation conducted in three water channels in the mouth bar area of the Changjiang Estuary during both spring and neap tides in July 2014. dFe showed high spatial variation, from 2.63 to 690 nM, with higher values commonly found in the inner study area. An episode of significant Fe remobilization was observed in the inner mouth bar before the removal in the subsequent fresh‐saline water mixing process. Averaged dFe concentration increased from 45.2 ± 22.9 nM at Xuliujing to 188 ± 185 nM in the inner salinity (S) ≤ 1 water, then decreased to 10.3 ± 9.53 nM in the outer S > 1 water. Budget calculations revealed that the Changjiang input was the largest terrestrial source for dFe, while desorption from particles was the main reason for dFe enhancement in the study area. The entire mouth bar area was identified as a net sink for dFe, whereas, its S ≤ 1 and S > 1 zones were a source and a sink, respectively. We suggest that the mouth bar area diversifies the biogeochemical behavior of Fe in the estuary and enhances Fe output flux. Our study offers a new insight for better understanding the behavior of Fe and other particle‐reactive elements in large dynamic estuaries.
The Structure of Martian Magnetosphere at the Dayside Terminator Region as Observed on MAVEN Spacecraft
Authors: Vaisberg O. L. , Ermakov V. N. , Shuvalov S. D. , Zelenyi L. M. , Halekas J. , DiBraccio G. A. , McFadden J. , Dubinin E. M.
Published: March 2018

We analyzed 44 passes of the Mars Atmosphere and Volatile EvolutioN mission (MAVEN) spacecraft through the magnetosphere, arranged by the angle between electric field vector and the projection of spacecraft position radius vector in the plane perpendicular to the Mars‐Sun line (θE). All passes were divided into three angular sectors near 0°, 90°, and 180° θE angles in order to estimate the role of the interplanetary magnetic field direction in plasma and magnetic properties of dayside Martian magnetosphere. The time interval chosen was from 17 January to 4 February 2016 when MAVEN was crossing the dayside magnetosphere at solar zenith angle ~70°. Magnetosphere as the region with prevailing energetic planetary ions is always found between the magnetosheath and the ionosphere. The analysis of dayside interaction region showed that for each angular sector with different orientation of the solar wind electric field vector E = −1/c V × B one can find specific profiles of the magnetosheath, the magnetic barrier (Michel, 1971, https://doi.org/10.1029/RG009i002p00427; Zhang et al., 1991, https://doi.org/10.1029/91JA00088), and the magnetosphere. Magnetic barrier forms in front of the magnetosphere, and relative magnetic field magnitudes in these two domains vary. The average height of the boundary with ionosphere is ~530 km, and the average height of the magnetopause is ~730 km. We discuss the implications of the observed magnetosphere structure to the planetary ions loss mechanism.