bluuebunny/crossref_metadata_2025 huggingface dataset:
Quand manger des fruits et légumes difformes contribue au bien-être alimentaire : analyse d’un oxymore par les valeurs
Authors: Debucquet Gervaise , Lombart Cindy
Published: October 2017

Cette recherche s’interroge sur l’apport des valeurs culturelles et individuelles, mises en évidence par Schwartz (1999, 2006), à la compréhension du bien-être alimentaire en lien avec l’esthétique des aliments. Une étude qualitative menée auprès de 30 individus a identifié deux profils de consommateurs, les « terriens/enracinés » et les « pragmatiques/déracinés », opposés par leurs conceptions du bien-être individuel en lien avec les fruits et légumes difformes. Ceux-ci réactivent chez les premiers les valeurs positives associées à la singularité naturelle et humaine mais génèrent une dissonance chez les seconds, davantage conditionnés par le calibrage de l’offre. La contribution au bien-être social doit également être nuancée selon les profils.
Le canal de distribution est-il source de bien-être pour le consommateur ? Une application à l’expérience d’achat de fruits et légumes
Authors: Gonzalez Christine , Séré de Lanauze Gilles , Siadou-Martin Béatrice
Published: October 2017

Au travers de leur consommation, les individus aspirent à construire leur image et à trouver le bien-être. Sur la base d’une étude quantitative réalisée auprès de 455 consommateurs, cette recherche examine les liens entre le canal de distribution fréquenté pour l’achat de fruits et légumes et le bien-être ressenti. Les résultats montrent que les valeurs de magasinage utilitaire, ludique et sociale et l’identification au canal de distribution jouent un rôle déterminant dans l’explication du bien-être. Leurs poids respectifs varient selon les canaux (GMS ou Marché). En découlent des propositions d’actions spécifiques dans le but d’enrichir l’offre des entreprises et l’expérience de consommation, source de bien-être.
Formes du bien-être et expériences de consommation : une application au secteur touristique
Authors: Abbes Intissar , Touil Saloua
Published: October 2017

Cet article s’attache à explorer le concept de bien-être en identifiant une typologie d’expériences touristiques et les formes du bien-être associées. Les résultats d’une étude qualitative menée auprès de 28 touristes francophones révèlent différents types d’expériences touristiques (marchande/non marchande) et natures de participation (interaction/participation active) et nous permettent de distinguer plusieurs formes de bien-être. Des préconisations managériales sont fournies aux professionnels du tourisme sur la manière d’améliorer les expériences de leurs clients en fonction des formes du bien-être recherchées.
Le mythe de Venise au XVIIe siècle. Perspectives de recherche en littérature française
Authors: Van Hamme Clément
Published: October 2017

La République de Venise s’est efforcée, du XVe siècle jusqu’à sa chute, de charger sa puissance politique et commerciale d’une double justification, politique et religieuse. En se servant des légendes orales qui circulaient depuis sa fondation, et en mettant en place une interprétation officielle de sa propre histoire, elle a fabriqué un mythe théologico-politique dont elle est le héros. Au tournant des XVIe et XVIIe siècles, alors que ce mythe atteint l’apogée de son influence chez le plus grand nombre des penseurs politiques européens, des contestations apparaissent, encouragées par les mutations de la méthode historique. Est-ce à dire que le mythe de Venise vit ses dernières heures ? Cet article se propose d’interroger la présence de traces du mythe politique vénitien chez les intellectuels français du XVIIe siècle. Ceux-ci, certes acquis à la lutte de Venise contre les abus politiques de la papauté depuis l’affaire de l’Interdit vénitien de 1606, prirent néanmoins part à un certain renouvellement méthodologique de l’écriture de l’histoire.
Die Nibelungen de Fritz Lang (Allemagne, 1924) : histoire du mythe, histoire du film et mise en abyme
Authors: Marzloff Alice
Published: October 2017

Cet article a pour objet le film Die Nibelungen de Fritz Lang (Allemagne, 1924). Nous présenterons les sources artistiques et historiques utilisées par Fritz Lang et nous montrerons comment le mythe, la légende et l’histoire interagissent dans le film grâce au dispositif de mise en abyme. Nous analyserons ensuite les processus de dévoiement effectués sur le film par le pouvoir nazi et nous expliquerons comment cette version s'est inscrite dans l’Histoire. Nous conclurons notre propos en présentant les travaux des archivistes et des historiens qui, après avoir restauré et reconstitué le film dans sa version de 1924, ont réhabilité l’oeuvre de Fritz Lang et ouvert de nouvelles perspectives d'interprétation.
Acerca del alcance objetivo de las prescripciones metodológicas de la función regulativa de la razón teórica en la "Crítica de la razón pura" de Kant
Authors: Arias Albisu Martin
Published: October 2017

En el 'Apéndice a la dialéctica trascendental' de su "Crítica de la razón pura", Kant presenta prescripciones metodológicas para el conocimiento empírico. Expondré los dos conjuntos de prescripciones más importantes de esa metodología: 1) la necesidad de introducir conceptos 'teóricos'; 2) el uso hipotético de la razón y la exigencia de sistematicidad, que se refieren a leyes empíricas y a los conceptos teóricos y empíricos empleados por tales leyes. Mi objetivo es presentar las diferencias y relaciones mutuas entre las dimensiones objetivas de la función regulativa de la razón teórica que cada una de estas prescripciones exige como correlato suyo.
Modalidades de autoconciencia en la "Reflexión de Leningrado"
Authors: Oroño Matías
Published: October 2017

Nuestro objetivo principal es señalar que los aspectos novedosos del manuscrito conocido como “Reflexión de Leningrado” no se hallan en el tratamiento de la auto-afección ni en los argumentos contra el idealismo cartesiano, sino en la formulación explícita de ciertas modalidades de autoconciencia que están íntimamente ligadas a la conciencia de la propia corporalidad.
Entre Alemania y América. José Casares Gil y los viajes científicos en la construcción de la autoridad experta en la España contemporánea
Authors: Suay-Matallana Ignacio
Published: October 2017

This article shows how scientific travels contribute decisively to the construction of expert authority. An example of this can be observed in studying the work of the chemist José Casares Gil (1866-1961), who, together with other Spanish scientists, made several trips to European and Latin American countries. Some had formative and academic objectives, but others were related to diplomacy and cultural mediation in different spaces. Furthermore, he formed part of institutions that promoted scientific exchanges to modernize pedagogical practices in the teaching of chemistry in Spain and in America. But he was also a chemist who developed links and networks of contacts among a variety of different countries, which benefited both the institutions involved and the experts themselves who thereby strengthened their own scientific authority.
Listas negras y protesta obrera. El Ferrocarril Central Argentino y sus trabajadores durante la Primera Guerra Mundial
Authors: Badaloni Laura
Published: October 2017

The main objective of this article is to analyze the corporate policies of the Ferrocarril Central Argentino and the workers’ responses in the context of World War I. In this sense, the research question it poses is: What was the impact of World War I in labor relations within a British railroad company installed in Argentina? Based on the triangulation of diverse types of sources (company files, union newspapers, official government documents and Foreign Office correspondence) it shows, on the one hand, the company’s symbolic use of the war to justify wage cuts and layoffs and to involve segments of the working class in support of the British army. On the other hand, it also shows the limitations of the company’s patriotic discourse and how its co-optation strategies failed to block the workers’ participation in violent protests.
Construcción de memoria: la dictadura a través de la ficción televisiva en Chile (2011)
Authors: Barrios Lorena Antezana , Mateos-Pérez Javier
Published: October 2017

During the commemoration of the fortieth anniversary of the military coup d’état in Chile, several new fiction programs that appeared on TV had repercussions in the public sphere. One of them was the series Los archivos del Cardenal. The case study of said series, which was considered good quality fiction, makes it possible to address the relation between TV fiction, memory, and recent history. The series presents very select, simplified messages about history, but also makes it possible to illustrate real episodes in a captivating way and to visualize topics that had been silenced during the transition to democracy. Thus, this article shows that TV series are a format that complements the representation of the history of important events for a given society. Concretely, Los archivos del Cardenal constructs a story about the dictatorship from the viewpoint of the political opposition and proposes a collective memory in concordance with it.
daf-16/FoxO promotes gluconeogenesis and trehalose synthesis during starvation to support survival
Authors: Hibshman Jonathan D , Doan Alexander E , Moore Brad T , Kaplan Rebecca EW , Hung Anthony , Webster Amy K , Bhatt Dhaval P , Chitrakar Rojin , Hirschey Matthew D , Baugh L Ryan
Published: October 2017

daf-16/FoxO is required to survive starvation in Caenorhabditis elegans, but how daf-16IFoxO promotes starvation resistance is unclear. We show that daf-16/FoxO restructures carbohydrate metabolism by driving carbon flux through the glyoxylate shunt and gluconeogenesis and into synthesis of trehalose, a disaccharide of glucose. Trehalose is a well-known stress protectant, capable of preserving membrane organization and protein structure during abiotic stress. Metabolomic, genetic, and pharmacological analyses confirm increased trehalose synthesis and further show that trehalose not only supports survival as a stress protectant but also serves as a glycolytic input. Furthermore, we provide evidence that metabolic cycling between trehalose and glucose is necessary for this dual function of trehalose. This work demonstrates that daf-16/FoxO promotes starvation resistance by shifting carbon metabolism to drive trehalose synthesis, which in turn supports survival by providing an energy source and acting as a stress protectant.
Public space in the Soviet city: A spatial perspective on mass protests in Minsk
Authors: Hansen Arve
Published: October 2017

In many capitals, the central public square is the place where people go en masse when they wish to voice their discontent. The squares used for such collective actions are diverse. Each square has its unique combination of symbols and history; they are used in different ways by the public; and they often have distinct physical characteristics. Yet, in social sciences, when determining what makes collective actions successful, space is often overlooked.In this article, I present an approach for analysing public space in relation to mass protests. I then apply this approach to the Belarusian capital Minsk, where virtually no protests have been successful during the post-Soviet period. In what ways are mass protests in Minsk affected by the perceived (symbolic), social and physical elements of the city’s public spaces? I examine the centre of Minsk in general, and analyse two central squares in particular. The article is based mainly on qualitative, semi-structured interviews with protesters, observers and opposition leaders; research literature; and on my own fieldwork and experiences from living in Minsk.I conclude that space is contributing to the difficulties facing the Belarusian opposition in several ways. 1) The perceived elements of Minsk and the two main squares do not have a preferable symbolic value to the opposition. 2) The social elements of the city show that the political centre is avoided by the public, thus making protests less noticeable. 3) This latter point is important, given that the physical elements of the squares makes policing particularly easy and swift. The physical elements of the squares also limit the protesters’ communication, movement and flexibility. I argue that a spatial perspective should be included in research on collective actions.
Natural feeding of juveniles of Lutjanus peru (Nichols and Murphy, 1922) (Lutjanidae: Perciformes) off the coast of Jalisco and Colima, Mexico
Authors: Saucedo-Lozano M , González-Sansón G , Chiappa-Carraza X
Published: October 2017

Natural feeding of juveniles of Lutjanus peru off the coast of Jalisco and Colima, Mexico, is analyzed. A total of 915 organisms were caught; 696 stomachs were examined and 219 were discarded because they were empty. Items in the stomach content were identified to the lowest possible taxonomic level. Numeric percentage, gravimetric percentage, frequency of occurrence and the index of relative importance were calculated for each prey. The diet of the organisms studied comprises mainly fish and stomatopods, of which members of the family Congridae and organisms of Squilla hancocki are the most abundant in the stomach content. Feeding variations occurred during the year and the diet varied with respect to fish length. A significant positive correlation between the length of the crustaceans consumed and fish length was found. Differences between fish length and prey length were further verified with the Kruskal-Wallis test. Distribution of L. peru juveniles was mostly restricted to the 20- and 40-m isobaths. Low values of abundance were found at 60 m. Diet overlap between months is more frequent when prey number is considered.
Feeding habits of the spotted rose snapper Lutjanus guttatus (Pisces: Lutjanidae) in the coast of Guerrero, Mexico
Authors: Rojas-Herrera AA , Chiappa-Carrara X
Published: October 2017

Stomach contents analysis was used to describe quantitatively the feeding habits of Lutjanus guttatus. A total of 239 organisms with fork lengths between 12 and 55 cm were collected monthly from February 1993 to January 1995 in the coast of Guerrero. This species consumed a wide variety of prey organisms, mainly small fishes (index of relative importance, IIR = 67.46%) of the families Engraulidae, Clupeidae and Bregmacerotidae. Crustaceans, represented by Reptantia, Natantia and Stomatopoda, were consumed less (IIR = 30.94%). The composition of the diet varied as a function of the fish size. Seasonal and sexual differences in the diet were not significant.
Estrogen receptor mutations and splice variants determined in liquid biopsies from metastatic breast cancer patients
Authors: Beije Nick , Sieuwerts Anieta M. , Kraan Jaco , Van Ngoc M. , Onstenk Wendy , Vitale Silvia R. , van der Vlugt‐Daane Michelle , Dirix Luc Y. , Brouwer Anja , Hamberg Paul , de Jongh Felix E. , Jager Agnes , Seynaeve Caroline M. , Jansen Maurice P. H. M. , Foekens John A. , Martens John W. M. , Sleijfer Stefan
Published: October 2017

Mutations and splice variants in the estrogen receptor (ER) gene, ESR1, may yield endocrine resistance in metastatic breast cancer (MBC) patients. These putative endocrine resistance markers are likely to emerge during treatment, and therefore, its detection in liquid biopsies, such as circulating tumor cells (CTCs) and cell‐free DNA (cfDNA), is of great interest. This research aimed to determine whether ESR1 mutations and splice variants occur more frequently in CTCs of MBC patients progressing on endocrine treatment. In addition, the presence of ESR1 mutations was evaluated in matched cfDNA and compared to CTCs. CellSearch‐enriched CTC fractions (≥5/7.5 mL) of two MBC cohorts were evaluated, namely (a) patients starting first‐line endocrine therapy (n = 43, baseline cohort) and (b) patients progressing on any line of endocrine therapy (n = 40, progressing cohort). ESR1 hotspot mutations (D538G and Y537S/N/C) were evaluated in CTC‐enriched DNA using digital PCR and compared with matched cfDNA (n = 18 baseline cohort; n = 26 progressing cohort). Expression of ESR1 full‐length and 4 of its splice variants (∆5, ∆7, 36 kDa, and 46 kDa) was evaluated in CTC‐enriched mRNA. It was observed that in the CTCs, the ESR1 mutations were not enriched in the progressing cohort (8%), when compared with the baseline cohort (5%) (P = 0.66). In the cfDNA, however, ESR1 mutations were more prevalent in the progressing cohort (42%) than in the baseline cohort (11%) (P = 0.04). Three of the same mutations were observed in both CTCs and cfDNA, 1 mutation in CTCs only, and 11 in cfDNA only. Only the ∆5 ESR1 splice variant was CTC‐specific expressed, but was not enriched in the progressing cohort. In conclusion, sensitivity for detecting ESR1 mutations in CTC‐enriched fractions was lower than for cfDNA. ESR1 mutations detected in cfDNA, rarely present at the start of first‐line endocrine therapy, were enriched at progression, strongly suggesting a role in conferring endocrine resistance in MBC.
Oceanic Residual Topography Agrees With Mantle Flow Predictions at Long Wavelengths
Authors: Yang Ting , Moresi Louis , Müller R. Dietmar , Gurnis Michael
Published: October 2017

Dynamic topography, the surface deflection induced by sublithosheric mantle flow, is an important prediction made by geodynamic models, but there is an apparent disparity between geodynamic model predictions and estimates of residual topography (total topography minus lithospheric and crustal contributions). We generate synthetic global topography fields with different power spectral slopes and spatial patterns to investigate how well the long‐wavelength (spherical degrees 1 to 3) components can be recovered from a discrete set of samples where residual topography has been recently estimated. An analysis of synthetic topography, along with observed geoid and gravity anomalies, demonstrates the reliability of signal recovery. Appropriate damping factors, which depend on the maximum degree in the spherical harmonic expansion that is used to fit the samples, must be applied to recover the long‐wavelength topography correctly; large damping factors smooth the model excessively and suppress residual topography amplitude and power spectra unrealistically. Recovered long‐wavelength residual topographies based on recent oceanic point‐wise estimates with different spherical expansion degrees agree with each other and with the predicted dynamic topography from mantle flow models. The peak amplitude of the long‐wavelength residual topography from oceanic observations is about 1 km, suggesting an important influence of large‐scale deep mantle flow.
The Influence of IMF Clock Angle on Dayside Flux Transfer Events at Mercury
Authors: Leyser Roger P. , Imber Suzanne M. , Milan Stephen E. , Slavin James A.
Published: October 2017

Analysis of MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) data has shown for the first time that the orientation of the interplanetary magnetic field (IMF) in the magnetosheath of Mercury plays a crucial role in the formation of flux transfer events (FTEs) at the dayside magnetopause. During the first 4 Hermean years of MESSENGER's orbit around Mercury, we have identified 805 FTEs using magnetometer data. Under conditions of near‐southward IMF, at least one FTE was detected on nearly 70% of passes through the magnetopause but the observation rate during northward IMF was less than 20%. FTEs were also observed preferentially in the prenoon sector.
Measuring the Elastic Modulus of Snow
Authors: Gerling B. , Löwe H. , van Herwijnen A.
Published: October 2017

The elastic modulus is the most fundamental mechanical property of snow. However, literature values scatter by orders of magnitude and hitherto no cross‐validated measurements exists. To this end, we employ P wave propagation experiments under controlled laboratory conditions on decimeter‐sized snow specimen, prepared from artificial snow and subjected to isothermal sintering, to cover a considerable range of densities (170–370 kg m−3). The P wave modulus was estimated from wave propagation speeds in transverse isotropic media and compared to microstructure‐based finite element (FE) calculations from X‐ray tomography images. Heterogeneities and size differences between acoustic and FE sample volumes were characterized by SnowMicroPen measurements, yielding an elastic modulus as a by‐product. The moduli (10–340 MPa) from the acoustic and FE method are in very good agreement (R2=0.99) over the entire range of densities. A remaining bias (24 %) between both methods can be explained by layer heterogeneities which systematically reduce the estimates from the acoustic method.
Oxygen Minimum Zone Contrasts Between the Arabian Sea and the Bay of Bengal Implied by Differences in Remineralization Depth
Authors: Al Azhar Muchamad , Lachkar Zouhair , Lévy Marina , Smith Shafer
Published: October 2017

The combination of high primary productivity and weak ventilation in the Arabian Sea (AS) and Bay of Bengal (BoB) generates vast areas of depleted oxygen, known as oxygen minimum zones (OMZs). The AS OMZ is the world's thickest and hosts up to 40% of global denitrification. In contrast, the OMZ in the BoB is weaker and denitrification free. Using a series of model simulations, we show that the deeper remineralization depth (RD) in the BoB, potentially associated with organic matter aggregation with riverine mineral particles, contributes to weaken its OMZ. When the RD is set uniformly across both seas, the model fails to reproduce the observed contrast between the two OMZs, irrespective of the chosen RD. In contrast, when the RD is allowed to vary spatially, the contrasting distributions of oxygen and nitrate are correctly reproduced, and water column denitrification is simulated exclusively in the AS, in agreement with observations.
The 2016 Kaikōura Earthquake Revealed by Kinematic Source Inversion and Seismic Wavefield Simulations: Slow Rupture Propagation on a Geometrically Complex Crustal Fault Network
Authors: Holden C. , Kaneko Y. , D'Anastasio E. , Benites R. , Fry B. , Hamling I. J.
Published: October 2017

The 2016 Kaikōura (New Zealand) earthquake generated large ground motions and resulted in multiple onshore and offshore fault ruptures, a profusion of triggered landslides, and a regional tsunami. Here we examine the rupture evolution using two kinematic modeling techniques based on analysis of local strong‐motion and high‐rate GPS data. Our kinematic models capture a complex pattern of slowly (Vr < 2 km/s) propagating rupture from south to north, with over half of the moment release occurring in the northern source region, mostly on the Kekerengu fault, 60 s after the origin time. Both models indicate rupture reactivation on the Kekerengu fault with the time separation of ~11 s between the start of the original failure and start of the subsequent one. We further conclude that most near‐source waveforms can be explained by slip on the crustal faults, with little (<8%) or no contribution from the subduction interface.
The Case Against an Early Lunar Dynamo Powered by Core Convection
Authors: Evans Alexander J. , Tikoo Sonia M. , Andrews‐Hanna Jeffrey C.
Published: October 2017

Paleomagnetic analyses of lunar samples indicate that the Moon had a dynamo‐generated magnetic field with ~50 μT surface field intensities between 3.85 and 3.56 Ga followed by a period of much lower (≤ ~5 μT) intensities that persisted beyond 2.5 Ga. However, we determine herein that there is insufficient energy associated with core convection—the process commonly recognized to generate long‐lived magnetic fields in planetary bodies—to sustain a lunar dynamo for the duration and intensities indicated. We find that a lunar surface field of ≤1.9 μT could have persisted until 200 Ma, but the ~50 μT paleointensities recorded by lunar samples between 3.85 and 3.56 Ga could not have been sustained by a convective dynamo for more than 28 Myr. Thus, for a continuously operating, convective dynamo to be consistent with the early lunar paleomagnetic record, either an exotic mechanism or unknown energy source must be primarily responsible for the ancient lunar magnetic field.
Lower Ionosphere Sensitivity to Solar X‐ray Flares Over a Complete Solar Cycle Evaluated From VLF Signal Measurements
Authors: Macotela Edith L. , Raulin Jean‐Pierre , Manninen Jyrki , Correia Emília , Turunen Tauno , Magalhães Antonio
Published: October 2017

The daytime lower ionosphere behaves as a solar X‐ray flare detector, which can be monitored using very low frequency (VLF) radio waves that propagate inside the Earth‐ionosphere waveguide. In this paper, we infer the lower ionosphere sensitivity variation over a complete solar cycle by using the minimum X‐ray fluence (FXmin) necessary to produce a disturbance of the quiescent ionospheric conductivity. FXmin is the photon energy flux integrated over the time interval from the start of a solar X‐ray flare to the beginning of the ionospheric disturbance recorded as amplitude deviation of the VLF signal. FXmin is computed for ionospheric disturbances that occurred in the time interval of December–January from 2007 to 2016 (solar cycle 24). The computation of FXmin uses the X‐ray flux in the wavelength band below 0.2 nm and the amplitude of VLF signals transmitted from France (HWU), Turkey (TBB), and U.S. (NAA), which were recorded in Brazil, Finland, and Peru. The main result of this study is that the long‐term variation of FXmin is correlated with the level of solar activity, having FXmin values in the range (1 − 12) × 10−7 J/m2. Our result suggests that FXmin is anticorrelated with the lower ionosphere sensitivity, confirming that the long‐term variation of the ionospheric sensitivity is anticorrelated with the level of solar activity. This result is important to identify the minimum X‐ray fluence that an external source of ionization must overcome in order to produce a measurable ionospheric disturbance during daytime.
Remote Linkages to Anomalous Winter Atmospheric Ridging Over the Northeastern Pacific
Authors: Swain Daniel L. , Singh Deepti , Horton Daniel E. , Mankin Justin S. , Ballard Tristan C. , Diffenbaugh Noah S.
Published: October 2017

Severe drought in California between 2013 and 2016 has been linked to the multiyear persistence of anomalously high atmospheric pressure over the northeastern Pacific Ocean, which deflected the Pacific storm track northward and suppressed regional precipitation during California's winter “rainy season.” Multiple hypotheses have emerged regarding why this high pressure ridge near the west coast of North America was so resilient—including unusual sea surface temperature patterns in the Pacific Ocean, reductions in Arctic sea ice, random atmospheric variability, or some combination thereof. Here we explore relationships between previously documented atmospheric conditions over the North Pacific and several potential remote oceanic and cryospheric influences using both observational data and a large ensemble of climate model simulations. Our results suggest that persistent wintertime atmospheric ridging similar to that implicated in California's 2013–2016 drought can at least partially be linked to unusual Pacific sea surface temperatures and that Pacific Ocean conditions may offer some degree of cool‐season foresight in this region despite the presence of substantial internal variability.
Winds in the Middle Cloud Deck From the Near‐IR Imaging by the Venus Monitoring Camera Onboard Venus Express
Authors: Khatuntsev I. V. , Patsaeva M. V. , Titov D. V. , Ignatiev N. I. , Turin A. V. , Fedorova A. A. , Markiewicz W. J.
Published: October 2017

For more than 8 years the Venus Monitoring Camera (VMC) onboard the Venus Express orbiter performed continuous imaging of the Venus cloud layer in UV, visible and near‐IR filters. We applied the correlation approach to sequences of the near‐IR images at 965 nm to track cloud features and determine the wind field in the middle and lower cloud (49–57 km). From the VMC images that spanned from December of 2006 through August of 2013 we derived zonal and meridional components of the wind field. In low‐to‐middle latitudes (5–65°S) the velocity of the retrograde zonal wind was found to be 68–70 m/s. The meridional wind velocity slowly decreases from peak value of +5.8 ± 1.2 m/s at 15°S to 0 at 65–70°S. The mean meridional speed has a positive sign at 5–65°S suggesting equatorward flow. This result, together with the earlier measurements of the poleward flow at the cloud tops, indicates the presence of a closed Hadley cell in the altitude range 55–65 km. Long‐term variations of zonal and meridional velocity components were found during 1,200 Earth days of observation. At 20° ± 5°S the zonal wind speed increases from −67.18 ± 1.81 m/s to −77.30 ± 2.49 m/s. The meridional wind gradually increases from +1.30 ± 1.82 m/s to +8.53 ± 2.14 m/s. Following Bertaux et al. (2016) we attribute this long‐term trend to the influence from the surface topography on the dynamical process in the atmosphere via the upward propagation of gravity waves that became apparent in the VMC observations due to slow drift of the Venus Express orbit over Aphrodite Terra.
Observations of Coherent Flow Structures Over Subaqueous High‐ and Low‐ Angle Dunes
Authors: Kwoll E. , Venditti J. G. , Bradley R. W. , Winter C.
Published: October 2017

Large‐scale coherent flow structures (CFSs) above dunes are the dominant source of flow resistance and constitute the principal mechanism for sediment transport and mixing in sand bed river and estuarine systems. Based on laboratory observations, CFS formation has been previously linked to flow separation downstream of high‐angle dunes with lee slopes of ~30°. How CFSs form in natural, deep rivers and estuaries where dunes exhibit lower lee slopes and intermittent flow separation is not well understood. Here we present particle image velocimetry measurements from an experiment where dune lee slope was systematically varied (30°, 20°, and 10°), while other geometric and hydraulic parameters were held constant. We show that CFSs form downstream of all three dune geometries from shear layer vortices in the dune lee. The mode of CFS formation undergoes a low‐frequency oscillation with periods of intense vortex shedding interspersed with periods of rare vortex shedding. Streamwise alignment of several vortices during periods of intense shedding results in wedge‐shaped CFSs that are advected above the dune stoss side. Streamwise length scales of wedge‐shaped CFS correspond to large‐scale motions (LSMs). We hypothesize that the advection of LSM over the dune crest triggers the periods of intense shedding in the dune lee. LSMs are weaker and smaller above low‐angle dunes; however, the low‐frequency oscillation in CFS formation periods persists. The formation of smaller and weaker CFS results in a reduction of flow resistance over low‐angle dunes.
Gauging Through the Crowd: A Crowd‐Sourcing Approach to Urban Rainfall Measurement and Storm Water Modeling Implications
Authors: Yang Pan , Ng Tze Ling
Published: October 2017

Accurate rainfall measurement at high spatial and temporal resolutions is critical for the modeling and management of urban storm water. In this study, we conduct computer simulation experiments to test the potential of a crowd‐sourcing approach, where smartphones, surveillance cameras, and other devices act as precipitation sensors, as an alternative to the traditional approach of using rain gauges to monitor urban rainfall. The crowd‐sourcing approach is promising as it has the potential to provide high‐density measurements, albeit with relatively large individual errors. We explore the potential of this approach for urban rainfall monitoring and the subsequent implications for storm water modeling through a series of simulation experiments involving synthetically generated crowd‐sourced rainfall data and a storm water model. The results show that even under conservative assumptions, crowd‐sourced rainfall data lead to more accurate modeling of storm water flows as compared to rain gauge data. We observe the relative superiority of the crowd‐sourcing approach to vary depending on crowd participation rate, measurement accuracy, drainage area, choice of performance statistic, and crowd‐sourced observation type. A possible reason for our findings is the differences between the error structures of crowd‐sourced and rain gauge rainfall fields resulting from the differences between the errors and densities of the raw measurement data underlying the two field types.
Sensitivity of Catchment Transit Times to Rainfall Variability Under Present and Future Climates
Authors: Wilusz Daniel C. , Harman Ciaran J. , Ball William P.
Published: October 2017

Hydrologists have a relatively good understanding of how rainfall variability shapes the catchment hydrograph, a reflection of the celerity of hydraulic head propagation. Much less is known about the influence of rainfall variability on catchment transit times, a reflection of water velocities that control solute transport. This work uses catchment‐scale lumped parameter models to decompose the relationship between rainfall variability and an important metric of transit times, the time‐varying fraction of young water (<90 days old) in streams (FYW). A coupled rainfall‐runoff model and rank StorAge Selection (rSAS) transit time model were calibrated to extensive hydrometric and environmental tracer data from neighboring headwater catchments in Plynlimon, Wales from 1999 to 2008. At both sites, the mean annual FYW increased more than 13 percentage points from the driest to the wettest year. Yearly mean rainfall explained most between‐year variation, but certain signatures of rainfall pattern were also associated with higher FYW including: more clustered storms, more negatively skewed storms, and higher covariance between daily rainfall and discharge. We show that these signatures are symptomatic of an “inverse storage effect” that may be common among watersheds. Looking to the future, changes in rainfall due to projected climate change caused an up to 19 percentage point increase in simulated mean winter FYW and similarly large decreases in the mean summer FYW. Thus, climate change could seasonally alter the ages of water in streams at these sites, with concomitant impacts on water quality.
Inclusion of Topological Measurements into Analytic Estimates of Effective Permeability in Fractured Media
Authors: Sævik P. N. , Nixon C. W.
Published: October 2017

We demonstrate how topology‐based measures of connectivity can be used to improve analytical estimates of effective permeability in 2‐D fracture networks, which is one of the key parameters necessary for fluid flow simulations at the reservoir scale. Existing methods in this field usually compute fracture connectivity using the average fracture length. This approach is valid for ideally shaped, randomly distributed fractures, but is not immediately applicable to natural fracture networks. In particular, natural networks tend to be more connected than randomly positioned fractures of comparable lengths, since natural fractures often terminate in each other. The proposed topological connectivity measure is based on the number of intersections and fracture terminations per sampling area, which for statistically stationary networks can be obtained directly from limited outcrop exposures. To evaluate the method, numerical permeability upscaling was performed on a large number of synthetic and natural fracture networks, with varying topology and geometry. The proposed method was seen to provide much more reliable permeability estimates than the length‐based approach, across a wide range of fracture patterns. We summarize our results in a single, explicit formula for the effective permeability.
Hydropower Optimization Using Artificial Neural Network Surrogate Models of a High‐Fidelity Hydrodynamics and Water Quality Model
Authors: Shaw Amelia R. , Smith Sawyer Heather , LeBoeuf Eugene J. , McDonald Mark P. , Hadjerioua Boualem
Published: October 2017

Hydropower operations optimization subject to environmental constraints is limited by challenges associated with dimensionality and spatial and temporal resolution. The need for high‐fidelity hydrodynamic and water quality models within optimization schemes is driven by improved computational capabilities, increased requirements to meet specific points of compliance with greater resolution, and the need to optimize operations of not just single reservoirs but systems of reservoirs. This study describes an important advancement for computing hourly power generation schemes for a hydropower reservoir using high‐fidelity models, surrogate modeling techniques, and optimization methods. The predictive power of the high‐fidelity hydrodynamic and water quality model CE‐QUAL‐W2 is successfully emulated by an artificial neural network, then integrated into a genetic algorithm optimization approach to maximize hydropower generation subject to constraints on dam operations and water quality. This methodology is applied to a multipurpose reservoir near Nashville, Tennessee, USA. The model successfully reproduced high‐fidelity reservoir information while enabling 6.8% and 6.6% increases in hydropower production value relative to actual operations for dissolved oxygen (DO) limits of 5 and 6 mg/L, respectively, while witnessing an expected decrease in power generation at more restrictive DO constraints. Exploration of simultaneous temperature and DO constraints revealed capability to address multiple water quality constraints at specified locations. The reduced computational requirements of the new modeling approach demonstrated an ability to provide decision support for reservoir operations scheduling while maintaining high‐fidelity hydrodynamic and water quality information as part of the optimization decision support routines.
Disturbance Hydrology: Preparing for an Increasingly Disturbed Future
Authors: Mirus Benjamin B. , Ebel Brian A. , Mohr Christian H. , Zegre Nicolas
Published: October 2017

This special issue is the result of several fruitful conference sessions on disturbance hydrology, which started at the 2013 AGU Fall Meeting in San Francisco and have continued every year since. The stimulating presentations and discussions surrounding those sessions have focused on understanding both the disruption of hydrologic functioning following discrete disturbances, as well as the subsequent recovery or change within the affected watershed system. Whereas some hydrologic disturbances are directly linked to anthropogenic activities, such as resource extraction, the contributions to this special issue focus primarily on those with indirect or less pronounced human involvement, such as bark‐beetle infestation, wildfire, and other natural hazards. However, human activities are enhancing the severity and frequency of these seemingly natural disturbances, thereby contributing to acute hydrologic problems and hazards. Major research challenges for our increasingly disturbed planet include the lack of continuous pre and postdisturbance monitoring, hydrologic impacts that vary spatially and temporally based on environmental and hydroclimatic conditions, and the preponderance of overlapping or compounding disturbance sequences. In addition, a conceptual framework for characterizing commonalities and differences among hydrologic disturbances is still in its infancy. In this introduction to the special issue, we advance the fusion of concepts and terminology from ecology and hydrology to begin filling this gap. We briefly explore some preliminary approaches for comparing different disturbances and their hydrologic impacts, which provides a starting point for further dialogue and research progress.
genRE: A Method to Extend Gridded Precipitation Climatology Data Sets in Near Real‐Time for Hydrological Forecasting Purposes
Authors: van Osnabrugge B. , Weerts A. H. , Uijlenhoet R.
Published: October 2017

To enable operational flood forecasting and drought monitoring, reliable and consistent methods for precipitation interpolation are needed. Such methods need to deal with the deficiencies of sparse operational real‐time data compared to quality‐controlled offline data sources used in historical analyses. In particular, often only a fraction of the measurement network reports in near real‐time. For this purpose, we present an interpolation method, generalized REGNIE (genRE), which makes use of climatological monthly background grids derived from existing gridded precipitation climatology data sets. We show how genRE can be used to mimic and extend climatological precipitation data sets in near real‐time using (sparse) real‐time measurement networks in the Rhine basin upstream of the Netherlands (approximately 160,000 km2). In the process, we create a 1.2 × 1.2 km transnational gridded hourly precipitation data set for the Rhine basin. Precipitation gauge data are collected, spatially interpolated for the period 1996–2015 with genRE and inverse‐distance squared weighting (IDW), and then evaluated on the yearly and daily time scale against the HYRAS and EOBS climatological data sets. Hourly fields are compared qualitatively with RADOLAN radar‐based precipitation estimates. Two sources of uncertainty are evaluated: station density and the impact of different background grids (HYRAS versus EOBS). The results show that the genRE method successfully mimics climatological precipitation data sets (HYRAS/EOBS) over daily, monthly, and yearly time frames. We conclude that genRE is a good interpolation method of choice for real‐time operational use. genRE has the largest added value over IDW for cases with a low real‐time station density and a high‐resolution background grid.
Copula‐Based Modeling of Flood Control Reservoirs
Authors: Balistrocchi M. , Orlandini S. , Ranzi R. , Bacchi B.
Published: October 2017

Copulas are shown in this paper to provide an effective strategy to describe the statistical dependence between peak flow discharge and flood volume featuring hydrographs forcing a flood control reservoir. A 52 year time series of flow discharges observed in the Panaro River (Northern Italian Apennines) is used to fit an event‐based bivariate distribution and to support time‐continuous modeling of a flood control reservoir, located online along the river system. With regard to reservoir performances, a method aimed at estimating the bivariate return period is analytically developed, by exploiting the derived distribution theory and a simplified routing scheme. In this approach, the return period is that of the peak flow discharge released downstream from the reservoir. Therefore, in order to verify the reliability of the proposed method, a nonparametric version of its frequency distribution is assessed by means of continuous simulation statistics. Copula derived and nonparametric distributions of the downstream peak flow discharge are found to be in satisfactory agreement. Finally, a comparison of bivariate return period estimates carried out by using alternative approaches is illustrated.
Structural enzymology comparisons of multifunctional enzyme, type‐1 (MFE1): the flexibility of its dehydrogenase part
Authors: Kasaragod Prasad , Midekessa Getnet B. , Sridhar Shruthi , Schmitz Werner , Kiema Tiila‐Riikka , Hiltunen Jukka K. , Wierenga Rik K.
Published: October 2017

Multifunctional enzyme, type‐1 (MFE1) is a monomeric enzyme with a 2E‐enoyl‐CoA hydratase and a 3S‐hydroxyacyl‐CoA dehydrogenase (HAD) active site. Enzyme kinetic data of rat peroxisomal MFE1 show that the catalytic efficiencies for converting the short‐chain substrate 2E‐butenoyl‐CoA into acetoacetyl‐CoA are much lower when compared with those of the homologous monofunctional enzymes. The mode of binding of acetoacetyl‐CoA (to the hydratase active site) and the very similar mode of binding of NAD+ and NADH (to the HAD part) are described and compared with those of their monofunctional counterparts. Structural comparisons suggest that the conformational flexibility of the HAD and hydratase parts of MFE1 are correlated. The possible importance of the conformational flexibility of MFE1 for its biocatalytic properties is discussed.

Database

Structural data are available in PDB database under the accession number 5MGB.
Morphological Characterization of the Self‐Assembly of Virus Movement Proteins into Nanotubes in the Absence of Virus Particles
Authors: Schwan Stefan , Ludtka Christopher , Friedmann Andrea , Cismak Andreas , Berthold Lutz , Goehre Felix , Kiesow Andreas , Heilmann Andreas
Published: October 2017

One infection mechanism of plant viruses is the generation of nanotubes by viral movement proteins, allowing cell‐to‐cell virus particle transport. Previously, it was assumed that viral nanotubes extend directly from the host‐cell plasma membrane. In virus‐infected plants, these nanotubes reach an extraordinary diameter:length ratio (≈100 nm:µm or mm range). Here, viral nanotubes are produced in a transient protoplast system; the coding sequence for alfalfa mosaic virus movement protein is translationally fused to green fluorescent protein. The maximum extension of viral nanotubes into the culture medium is achieved 24–48 h posttransfection, with lengths in the micro‐ and millimeter ranges. Scanning electron microscopy and transmission electron microscopy show that strong inhomogeneous viral nanotubes are formed compared to particle‐filled systems. The nanotubes have similar length, but fluctuating wall thickness and diameter and are susceptible to entanglement and recombination. Indirect methods demonstrate that movement proteins assemble independently at the top of the nanotube. These viral nanotubes grow distinctly from previously known natural particle‐filled systems and are a unique biological tubular nanomaterial that has the potential for micro‐ or nanoapplications as a mechanically stable structural component.
Fabrication and Optical Properties of Periodic Ag Nano‐Pore and Nano‐Particle Arrays with Controlled Shape and Size over Macroscopic Length Scales
Authors: Mallon Colm T. , Kho Kiang W. , Gartite Houda , Forster Robert J. , Keyes Tia E.
Published: October 2017

A facile and economical route to preparation of highly ordered sliver pore or particle arrays with controlled pore‐shape and size extended over cm2 areas is described. The substrates are prepared at planar and curved surfaces via sphere‐imprinted polymer (PDMS) templating using polystyrene spheres with diameters of 820, 600, or 430 nm. Nano‐pore arrays are created by sputtering 80 nm of Ag directly onto the templates and nano‐particle arrays are prepared by electrode‐less deposition of Ag from Tollen's reagent. The shape of the nano‐pore or particles in the array conformed to that of the imprint of the sphere on the template. Stretching the flexible template enable creation of cuboid shaped nano‐voids and nano‐particles following Ag deposition. Diffuse reflectance from the spherical Ag nano‐cavity arrays showed absorbance maxima at wavelengths comparable similar to the diameter of the templating sphere, whereas reflectance from the cuboid arrays, showed little correlation with the sphere diameter. The cuboid nano‐particle arrays showed the most intense visible absorption which is red‐shifted compared to the spherical arrays. White light diffraction from the arrays, observed by rotating 1 cm2 substrates relative to a fixed light source, reflected exactly the symmetry axes of the periodic nano‐features in the arrays demonstrating the remarkable macroscopic order of the periodic structures. Raman spectra of 1‐benzenethiol adsorbed at the arrays indicated SERS enhancements from the substrates are attributed mainly to surface nano‐roughness with only moderate contributions from the periodically corrugated structures. Despite excitation at the major resonance dip in the reflectance spectrum, a weak, localized rim dipole mode is found to elicit a small increase in the SERS enhancement factor for the 430 nm diameter spherical arrays. FDTD studies of nano‐void arrays provided insights into various factors affecting the SERS experiment and confirmed the array's plasmonic spectra are dominated by propagating plasmon modes under microscope excitation/collection angles.