bluuebunny/crossref_metadata_2025 huggingface dataset:
Relationships between Interest, Current, and Future Participation in Activities: Japanese Interest Checklist for the Elderly
Authors: Nakamura-Thomas Hiromi , Kyougoku Makoto , Forsyth Kirsty
Published: February 2014

Introduction:

This study examined the relationship between interest, current participation, and desire for future participation in each activity listed in the Japanese Interest Checklist for the Elderly.

Method:

Data were collected from 375 community-dwelling older Japanese people through individual interviews using the revised Japanese Interest Checklist for the Elderly, which contains 25 activities. Responses in interest, current participation, and desire for future participation were analysed across activity and gender.

Findings:

Interest, current participation, and desire for future participation in activities correlated significantly and positively for both genders. Three different situations were identified: (1) participants could not currently participate in activities despite showing interest; (2) they were not currently engaged in activities but wished to participate them in the future; and (3) they preferred not to participate in the specific activities in the future, despite currently showing interest.

Conclusion:

There is a need for occupational therapists, therefore, to understand these findings in considering appropriate therapeutic options. Moreover, occupational therapists need to determine whether the person prefers not to participate in some activities, despite showing interest and/or participation in interests more generally.
Die rol van Nederland in die transnasionale beweging van enkele Afrikaanse skrywers
Authors: Viljoen Louise
Published: February 2014

This article explores the role that the Netherlands play in the transnational movement of Afrikaans authors. Because of the historical ties between the Netherlands and South Africa and the similarities between the languages Dutch and Afrikaans, Afrikaans authors and their texts often gain an audience in the Netherlands. This article posits the idea that the interaction between the Dutch and the Afrikaans literary systems form part of a ‘minor transnationalism’ (Lionnet & Shih 2005) of a specific kind: the ‘vertical movement’ of texts from a marginal literature (Afrikaans literature) to a literature placed in the European, metropolitan ‘centre’ that does not necessarily occupy an important place in that centre (Dutch literature). The article focuses on the literary careers of five Afrikaans authors who have a high profile both in the Netherlands and the larger, international world, namely André Brink, Breyten Breytenbach, Etienne van Heerden, Antjie Krog and Marlene van Niekerk. It attempts to discern whether exposure in the Netherlands led to exposure in the larger world. Several factors are taken into account: the position of Afrikaans literature in South Africa, the role of translation, the impact of genre, the influence of Western intellectual discourses and the importance of political acuity.
OH regeneration from methacrolein oxidation investigated in the atmosphere simulation chamber SAPHIR
Authors: Fuchs H. , Acir I.-H. , Bohn B. , Brauers T. , Dorn H.-P. , Häseler R. , Hofzumahaus A. , Holland F. , Kaminski M. , Li X. , Lu K. , Lutz A. , Nehr S. , Rohrer F. , Tillmann R. , Wegener R. , Wahner A.
Published: February 2014

Abstract. Hydroxyl radicals (OH) are the most important reagent for the oxidation of trace gases in the atmosphere. OH concentrations measured during recent field campaigns in isoprene rich environments were unexpectedly large. A number of studies showed that unimolecular reactions of organic peroxy radicals (RO2) formed in the initial reaction step of isoprene with OH play an important role for the OH budget in the atmosphere at low mixing ratios of nitrogen monoxide (NO) of less than 100 pptv. It has also been suggested that similar reactions potentially play an important role for RO2 from other compounds. Here, we investigate the oxidation of methacrolein (MACR), one major oxidation product of isoprene, by OH in experiments in the simulation chamber SAPHIR under controlled atmospheric conditions. The experiments show that measured OH concentrations are approximately 50% larger than calculated by current chemical models for conditions of the experiments (NO mixing ratio of 90 pptv). The analysis of the OH budget reveals a so far unaccounted OH source, which is correlated with the production rate of RO2 radicals from MACR. In order to balance the measured OH destruction rate, (0.77±0.3) OH radicals need to be additionally reformed from each OH that has reacted with MACR. The strong correlation of the missing OH source with the production of RO2 radicals is consistent with the concept of OH formation from unimolecular isomerization and decomposition reactions of RO2. The comparison of observations with model calculations gives a lower limit of 0.03 s−1 for the reaction rate constant, if the OH source is attributed to an isomerization reaction of one RO2 species formed in the MACR+OH reaction as suggested in literature. This fast isomerization reaction would be competitive to the reaction of this RO2 species with minimum 150 pptv NO.
Climate regime and soil storage capacity interact to effect evapotranspiration in western United States mountain catchments
Authors: Garcia E. S. , Tague C. L.
Published: February 2014

Abstract. In the winter-wet, summer-dry forests of the western United States (US), total annual evapotranspiration (ET) is largely a function of three separate but interacting properties: (1) climate, especially magnitude of precipitation, its partitioning into rain or snow, and snowmelt timing; (2) soil characteristics, including soil water holding capacity and rates of drainage; and (3) the total biomass where larger, more abundant vegetation is directly proportional to greater ET. Understanding how these controls influence ET in Mediterranean mountain environments is complicated by shifts between water and energy limitations both within the year and between years. We use a physically based process model to evaluate the strength of climate controls and soil properties in predicting ET in three snow-dominated, mountainous catchments in the western US. As we expect, statistical analysis shows that annual precipitation is a primary control of annual ET across all catchments. However, secondary climate controls vary across catchments. Further, the sensitivity of annual ET to precipitation and other climatic controls varies with soil characteristics. In the drier, more snow-dominated catchments ET is also controlled by spring temperature through its influence on the timing of snowmelt and the synchronicity between seasonal water availability and demand. In wetter catchments that receive a large fraction of winter precipitation as rainfall, the sensitivity to ET is also strongly influenced by soil water holding capacity. We show that in all catchments, soil characteristics affect the sensitivity of annual ET to climatic drivers. Estimates of annual ET become more sensitive to climatic drivers at low soil water holding capacities in the catchments with the stronger decoupling between precipitation and growing season demands.
Numerical simulations of tsunamis generated by underwater volcanic explosions at Karymskoye lake (Kamchatka, Russia) and Kolumbo volcano (Aegean Sea, Greece)
Authors: Ulvrová M. , Paris R. , Kelfoun K. , Nomikou P.
Published: February 2014

Abstract. Increasing human activities along the coasts of the world provoke the necessity to assess tsunami hazard from different sources (earthquakes, landslides, volcanic activity). In this paper, we simulate tsunamis generated by underwater volcanic explosions from (1) a submerged vent in a shallow water lake (Karymskoye Lake, Kamchatka), and (2) from Kolumbo submarine volcano (7 km NE of Santorini, Aegean Sea, Greece). The 1996 tsunami in Karymskoye lake is a well-documented example and thus serves as a case study for validating the calculations. The numerical model reproduces realistically the tsunami run-ups measured onshore. Systematic numerical study of tsunamis generated by explosions of the Kolumbo volcano is then conducted for a wide range of energies. Results show that in case of reawakening, the Kolumbo volcano might represent a significant tsunami hazard for the northern, eastern and southern coasts of Santorini, even for small-power explosions.
Permafrost-Affected Soils of the Russian Arctic and their Carbon Pools
Authors: Zubrzycki S. , Kutzbach L. , Pfeiffer E.-M.
Published: February 2014

Abstract. Permafrost-affected soils have accumulated enormous pools of organic matter during the Quaternary Period. The area occupied by these soils amounts to more than 8.6 million km2, which is about 27% of all land areas north of 50° N. Therefore, permafrost-affected soils are considered to be one of the most important cryosphere elements within the climate system. Due to the cryopedogenic processes that form these particular soils and the overlying vegetation that is adapted to the arctic climate, organic matter has accumulated to the present extent of up to 1024 Pg (1 Pg = 1015 g = 1 Gt) of soil organic carbon stored within the uppermost three meters of ground. Considering the observed progressive climate change and the projected polar amplification, permafrost-affected soils will undergo fundamental property changes. Higher turnover and mineralization rates of the organic matter are consequences of these changes, which are expected to result in an increased release of climate-relevant trace gases into the atmosphere. As a result, permafrost regions with their distinctive soils are likely to trigger an important tipping point within the global climate system, with additional political and social implications. The controversy of whether permafrost regions continue accumulating carbon or already function as a carbon source remains open until today. An increased focus on this subject matter, especially in underrepresented Siberian regions, could contribute to a more robust estimation of the soil organic carbon pool of permafrost regions and at the same time improve the understanding of the carbon sink and source functions of permafrost-affected soils.
Influence of regional precipitation patterns on stable isotopes in ice cores from the central Himalayas
Authors: Pang H. , Hou S. , Kaspari S. , Mayewski P. A.
Published: February 2014

Abstract. Several ice cores have been recovered from the Dasuopu (DSP) Glacier and the East Rongbuk (ER) Glacier in the central Himalayas since the 1990s. Although the distance between the DSP and the ER ice core drilling sites is only ~ 125 km, the stable isotopic record (δ18O or δD) of the DSP core is interpreted in previous studies as a temperature proxy, while the ER core is interpreted as a precipitation proxy. Thus, the climatological significance of the stable isotopic records of these Himalayan ice cores remains a subject of debate. Based on analysis of regional precipitation patterns over the region, we find that remarkable discrepancy in precipitation seasonality between the two sites may account for their disparate isotopic interpretations. At the ER core site, the Indian summer monsoon (ISM) precipitation is dominating due to topographic blocking of the moisture from westerlies by the high ridges of Mt. Qomolangma (Everest), which results in a negative correlation between the ER Δ18O or δD record and precipitation amount along the southern slope of the central Himalayas in response to the "amount effect". At the DSP core site, in comparison with the ISM precipitation, the wintertime precipitation associated with the westerlies is likely more important owing to its local favorable topographic conditions for interacting with the western disturbances. Therefore, the DSP stable isotopic record may be primarily controlled by the westerlies. Our results have important implications for interpreting the stable isotopic ice core records recovered from different climatological regimes of the Himalayas.
Seasonal changes of ice surface characteristics and productivity in the ablation zone of the Greenland Ice Sheet
Authors: Chandler D. M. , Alcock J. D. , Wadham J. L. , Mackie S. L. , Telling J.
Published: February 2014

Abstract. Field and remote sensing observations in the ablation zone of the Greenland Ice Sheet have revealed a diverse range of ice surface characteristics, primarily reflecting the variable distribution of fine debris (cryoconite). This debris reduces the surface albedo and is therefore an important control on melt rates and ice sheet mass balance. Meanwhile, studies of ice sheet surface biological processes have found active microbial communities associated with the cryoconite debris, which may themselves modify the cryoconite distribution. Due to the considerable difficulties involved with collecting ground-based observations of the ice surface, our knowledge of the physical and biological surface processes, and their links, remains very limited. Here we present data collected at a field camp established in the ice sheet ablation zone at 67° N, occupied for almost the entire melt season (26 May–10 August 2012), with the aim of gaining a much more detailed understanding of the physical and biological processes occurring on the ice surface. These data sets include quadrat surveys of surface type, measurements of ice surface ablation, and in-situ biological oxygen demand incubations to quantify microbial activity. In addition, albedo at the site was retrieved from AVHRR remote sensing data. Observations of the areal coverage of different surface types revealed a rapid change from complete snow cover to the "summer" ice surface of patchy debris ("dirty ice") and cryoconite holes. There was significant correlation between surface albedo, cryoconite hole coverage and cryoconite hole productivity during the main melt season, but microbial activity in "dirty ice" was not correlated with albedo and varied widely throughout the season. While this link suggests the potential for a remote-sensing approach to monitoring cryoconite hole biological processes, very wide seasonal and spatial variability in net surface productivity demonstrates the need for caution when extrapolating point measurements of biological processes to larger temporal or spatial scales.
Assemblages of Anarchists:
Authors: Ferguson Kathy E.
Published: February 2014

This article looks at the journal Mother Earth, a journal printed by Emma Goldman. Arguing that readers and viewers, as aesthetic subjects, are not pre-given individuals who then pick up a journal, this article maintains that audience members are themselves events, that they emerge from within the available opportunities to look and to read. Anarchist journals allowed aesthetic subjects to emerge, perhaps to thrive, through the process of self-creation and the making of a collective sensibility of resistance and hope.
Revolution Is Creativity:
Authors: Gurianova Nina
Published: February 2014

Interconnections between art, politics, aesthetics and ethics are a long-standing feature of Russian civil society, and this is particularly true during the tumultuous era of Russian revolution (1917–18). In this article I am examining the social and cultural politics of the two Moscow anarchist publications, the unique issue of a journal Revolutsionnoe Tvorchestvo (Revolutionary Creativity), and newspaper Anarkhiia (Anarchy) published by Moscow Federation of Anarchist Groups, and the role of the avant-garde artists in the paper. The cultural and political symbolism of creative activity was integral to the political philosophy of Anarkhiia. Contributions from avant-garde artists and poets in the “Creativity” section of Anarkhiia are very significant: these artists had never participated in such a controversial forum before. Their involvement indicates they not only perceived the Russian Revolution through the prism of anarchist aesthetics as a path “to the new limit” (Malevich's formulation), they openly associated these aesthetics with the movement's political agenda.
Pragmatic Naturalism and Social Cooperation
Authors: Schulkin Jay
Published: February 2014

A profound sense of biological explanations and the social nature of our species were appreciated by Chauncey Wright and American classical pragmatists. Inquiry was understood in the context of social cooperation. One achievement in the evolution of cephalic function is the development of social cooperative behaviors, the cornerstone of our cultural productivity. Classical pragmatism is linked to an expanding sense of human capability, tied to the deepening of human experience. While pragmatism is open-ended, the limits of human function put our advances into a perspective in which the evolution of function is just as apparent as the devolution of function.
Periodic fever, aphthous stomatitis, pharyngitis, and adenitis syndrome, Hodgkin's lymphoma,and the familial Mediterranean fever gene
Authors: Atamna Ala , Hershkovici Corina , Elis Avishay
Published: February 2014

The syndrome of periodic fever, aphthous stomatitis, pharyngitis, and adenopathy (PFAPA) is a benign, self-limited, auto-inflammatory disorder. The attacks usually start at age 2 to 5 years and cease before the age of 10 years. Affected children grow and develop normally and experience no long-term sequelae. The course of PFAPA syndrome is attenuated by the carrier state of the familial Mediterranean fever (FMF) gene, MEFV. A high rate of MEFV mutations has also been reported in various hemato-lymphoid neoplasms. We describe a 19-year-old woman with PFAPA syndrome in remission who was diagnosed with Hodgkin's lymphoma. Although mutations in the FMF gene were not found in this case, the association of PFAPA syndrome with FMF gene mutations and hematological malignancies is discussed.
The role of multidetector computed tomography for detecting aortic root pseudoanerysms complicating infective endocarditis
Authors: Hoey Edward Thomas Douglas , Rajoo Sangeetha
Published: February 2014

Echocardiography is the mainstay imaging technique for detecting infective endocarditis vegetations but may struggle to detect and characterise complicating features. There is increasing interest in the use of multidetector computed tomography (MDCT) as an adjunct to echocardiography, especially where there is concern for abscess or pseudoaneurysm formation. We present the case of a 70-year-old male with bio-prosthetic aortic valve endocarditis complicated by a large infected left ventricular outflow tract pseudoaneurysm which was diagnosed using MDCT angiography. Radiologists and clinicians should be aware of the emerging role of MDCT in this setting in order to advise and direct an appropriate imaging strategy.
Red Land/Black Land
Authors: Watrall Ethan
Published: February 2014

While digital games are used for health intervention, language training, and science learning, there are few instances of games being used to teach archaeology. This is a missed opportunity, as narratives of exploration and discovery make archaeology well suited to digital games. This article discusses Red Land/Black Land, a prototype Civilization V mod (modification of an existing game) that allows players to explore both the process of cultural change in ancient Egypt and the construction of archaeological knowledge about ancient Egypt. As a case study of scholarly game design, the article explores the project’s development. Included is a discussion of play mechanics, the merits and process of modding, and the resources required to build games in academic environments. The article also discusses preliminary efforts to test the game in an undergraduate classroom. Ultimately, the article argues that digital games are powerful tools for communicating archaeology. Instead of falling under the glamour of commercial games, however, scholars should adopt cost effective approaches to game design, looking to mobile play, alternate reality games, modding, and browser based games to realize their vision. The article also argues that the actual process of designing a game is an excellent tool to teach archaeology.
Fire Intensity Assessment through the Analysis of Artifacts and Building Materials
Authors: Inomata Takeshi
Published: February 2014

Different types of artifacts and building materials react in varying manners to heat exposure, and the analysis of their degrees and patterns of thermal alterations provide important clues to the intensity of fire to which they were subjected. Such data allow researchers to examine the presence or absence of a building fire, the quantity of fuel, and the intentional or accidental nature of the fire. This approach is particularly important in the tropical lowlands, where evidence of fire in the forms of charcoal and ash may not be well preserved. At the rapidly abandoned site of Aguateca, Guatemala, the amount of charcoal and ash was small, but the examination of numerous artifacts left in situ and of building materials identified clear evidence that many buildings were burned at the time of abandonment. Similar lines of evidence were also found in artifact-poor, gradually abandoned structures at Ceibal, Guatemala. These results suggest the possibility that the burning of structures at the time of abandonment may have been more common in the Maya Lowlands than generally thought.
Spanish History in The Fairy Country: Dealing with Social Trauma in 'Pan's Labyrinth'
Authors: Fernández Alvaro
Published: February 2014

Resumen: La celebrada El laberinto del fauno (Del Toro, 2006) pone en escena un cuento de hadas situado en los convulsos tiempos de la primera posguerra civil española. La crítica ha señalado las dificultades para evaluar la conflictiva relación entre historia y fantasía en el ambiguo final feliz de la película, y ha tratado de relacionar la moraleja final con el trauma de la Guerra Civil.En este trabajo, preferimos leer el film a la luz de otro trauma social, el que marca el momento de su producción. Si tenemos en cuenta que la Transición de una dictadura fascista a una monarquía parlamentaria no ha sido abierta ni pacíficamente debatida en las décadas siguientes y que cierto silencio sobre este tema persiste todavía hoy; es posible entender la película como una forma de abordar algunos asuntos pendientes de la cultura española contemporánea.Palabras Clave: Laberinto del Fauno, Del Toro, Trauma Social, Memoria Histórica, Transición Española, Cultura Española.Abstract: The successful film El laberinto del fauno (Del Toro, 2006) presents a fairy tale set in the convulsive times of the Spanish Civil War’s aftermath. The scholarship on this film already established the difficulties inherent in evaluating the conflictive relation between history and fantasy in the movie’s ambiguous happy ending and has tried to relate the film's moral with the social trauma of the Civil War. In this essay, we chose to read the film in the light of another social trauma, that which marked the moment of its production. Considering that the Transition from a fascist dictatorship to a parliamentary monarchy has not been openly and peacefully discussed in the subsequent decades, and that a tense silence in regards to this topic continues to this very day, it is possible to understand the movie as an attempt to address some unfinished business in contemporary Spanish culture.   Key Words: Pan’s Labyrinth, Del Toro, Social Trauma, Historical Memory, Spanish Transition, Spanish Culture.
De las experiencias y cruces en el discurso de la memoria: de la involuntaria en Proust a la del Polidor en '62/ Modelo para armar' de Cortázar
Authors: Dulou Jérôme
Published: February 2014

Resumen Este trabajo propone un análisis intertextual de las primeras páginas de la novela de Julio Cortázar, 62/Modelo para armar. Intenta poner en evidencia un diálogo con el autor francés Marcel Proust, cruzando el discurso proustiano sobre la memoria con el de la experiencia vivida por el personaje principal de la novela en el restaurante Polidor. Al describir con precisión como Juan vive la experiencia del Polidor y al compararla con las que vive el Narrador en Le Temps retrouvé, este trabajo intentará exponer el diálogo que se establece en estas páginas sobre temas literarios tan relevantes como los recuerdos, las asociaciones analógicas de imágenes, la inteligencia y las metáforas.   Palabras clave: Cortázar, Proust, discurso, experiencia, memoria   Abstract This work proposes an intertextual analysis of the first pages of the novel of Julio Cortázar, 62/Modelo para armar. It tries to bring to light a dialog with the French author Marcel Proust, crossing the proustian speech on the memory with that of the experience lived by the main character of the novel in the restaurant Polidor. By describing accurately as Juan lives the experience of the Polidor and by comparing it with those that the Narrator lives in Le Temps retrouvé, this work intends to expose the dialog which is established in these pages around literary topics so relevant as recollections, analogical associations of images, intelligence and metaphors.   Keywords: Cortázar, Proust, speech, experience, memory
'Nostalgia de la luz' de Patricio Guzmán: el cine como máquina del tiempo
Authors: Vitullo Julieta
Published: February 2014

Resumen: En su último documental, Nostalgia de la luz (2010), el cineasta chileno Patricio Guzmán va más allá de la concepción de filmes anteriores en los que utilizaba la  memoria como tema y motor de los relatos. Ya no se trata solamente de un uso de la memoria como mecanismo para revisitar el pasado, entender el presente y construir el  futuro. Ahora el cine como artificio que posibilita metáforas y abre caminos para un viaje por el tiempo se presenta como una máquina de indagación y sondeo, capaz de intervenir sobre los anclajes materiales de la memoria. En este documental, Guzmán incorpora toda la trayectoria de sus filmes anteriores y redobla la apuesta: el cine permite transitar diferentes temporalidades, y en lugar de utilizar los objetos o el paisaje solamente como  metáforas y disparadores de memoria, interviene sobre ellos y los pone en diálogo con esas temporalidades para darles un significado.   Palabras Clave: memoria, Nostalgia de la luz, cine, tiempo, objetos, paisaje, Patricio Guzmán. Abstract: In his last documentary, Nostalgia for the Light (2010), Chilean filmmaker Patricio Guzmán goes beyond the notions of some of his previous films in which he used memory both as a topic and a motor of his narratives. Memory is not just a mechanism that allows the film to revisit the past, understand the present and build the future. More than that, now cinema is an artifice that enables the use of metaphors, opens up paths that lead towards a travel through time and presents itself as a machine of inquiry and exploration, able to intervene on the material anchors of memory. In this documentary, Guzmán incorporates the trajectory of his previous films and doubles down his bet: his cinema is able to go through different temporalities and, instead of having the objects and landscapes be just metaphors or memory triggers, it intervenes on them and lets them engage in a dialogue with those temporalities in order to reach new meanings.   Key Words: memory, Nostalgia for the Light, cinema, time, objects, landscapes, Patricio Guzmán.
Un lugar que no existe: la poesía de Antonio Méndez Rubio (1995-2005)
Authors: Molina Gil Raúl
Published: February 2014

Resumen: En el presente trabajo se realiza un análisis de la poética de Antonio Méndez Rubio focalizado en cuatro de sus obras: El fin del mundo (1995), Un lugar que no existe (1998), Trasluz (2002) y Por más señas (2005). Tras un estudio del marco literario y socio-político en el que se ubican, planteamos: primero, una descripción del lenguaje poético que proviene de la aplicación de una metodología, de carácter pragmático, que nos permite analizar la modalización lírica y, con ello, los espacios de indeterminación que presenta; posteriormente, caracterizamos al sujeto lírico marcado por la falta partiendo de la vinculación que se da entre este y el mundo, y finalizando con la aplicación de las teorías de Jean Baudrillard sobre la hiperrealidad y los simulacros.     Palabras Clave: Antonio Méndez Rubio, poesía y sociedad, política, espacios de indeterminación, falta, simulacro
Atomic model of the F420-reducing [NiFe] hydrogenase by electron cryo-microscopy using a direct electron detector
Authors: Allegretti Matteo , Mills Deryck J , McMullan Greg , Kühlbrandt Werner , Vonck Janet
Published: February 2014

The introduction of direct electron detectors with higher detective quantum efficiency and fast read-out marks the beginning of a new era in electron cryo-microscopy. Using the FEI Falcon II direct electron detector in video mode, we have reconstructed a map at 3.36 Å resolution of the 1.2 MDa F420-reducing hydrogenase (Frh) from methanogenic archaea from only 320,000 asymmetric units. Videos frames were aligned by a combination of image and particle alignment procedures to overcome the effects of beam-induced motion. The reconstructed density map shows all secondary structure as well as clear side chain densities for most residues. The full coordination of all cofactors in the electron transfer chain (a [NiFe] center, four [4Fe4S] clusters and an FAD) is clearly visible along with a well-defined substrate access channel. From the rigidity of the complex we conclude that catalysis is diffusion-limited and does not depend on protein flexibility or conformational changes.
Influence of substrates on resistive switching behaviors of V-doped SrTiO3 thin films
Authors: Tang Zhenhua , Xiong Ying , Tang Minghua , Cheng Chuanpin , Xu Dinglin , Xiao Yongguang , Zhou Yichun
Published: February 2014

V-doped SrTiO3 (V:STO) thin films on Si and Pt/Ti/SiO2/Si substrates are synthesized by sol–gel method to form metal–insulator–metal (MIM) structures. Bipolar resistive switching (RS) characteristics were investigated in Pt/V:STO/Si and Pt/V:STO/Pt structures respectively. The enhancement of resistive switching behavior in Pt/V:STO/Pt/Ti/SiO2/Si structures were demonstrated in terms of the maximum operation voltage reduced from 20 to 2 V and the improved R
OFF/R
ON ratio increased from 102 to 103. The electrochemical migration of oxygen vacancies resulted from the metal–oxide interfaces was applied to explain the resistive switching behaviors. On the basis of current–voltage characteristics, the switching mechanisms for the low resistance state (LRS) and high resistance state (HRS) currents of V:STO films are considered as Ohmic and trap-controlled space charge-limited current (SCLC) behavior, respectively.
Space Weather Quarterly Is a Jewel in AGU's Crown
Authors: Crooker Nancy
Published: February 2014

Space Weather Quarterly (SWQ) is an attractive, glossy, hands‐on magazine unlike anything else AGU publishes. It is beginning to be recognized as a showcase publication for promoting the goals of one of the four pillars of AGU's strategic plan: science and society.
Science Is Important, but Politics Drives the Siting of Nuclear Waste Repositories
Authors: Shaw George H.
Published: February 2014

In 1982, I worked on the Nuclear Waste Policy Act as an AGU Congressional Science Fellow tasked with assisting a member of the House Energy and Commerce Committee. When I recently read the suggestion that clay‐rich strata (shales) could be a viable medium for high‐level nuclear waste (HLW) disposal [Neuzil, 2013], I could not help but remember the insights I gained more than 30 years ago from my time on the Hill.
Science Is the First Step to Siting Nuclear Waste Repositories
Authors: Neuzil C. E.
Published: February 2014

As Shaw [2014] notes, U.S. research on shale as a repository host was halted before expending anything close to the effort devoted to studying crystalline rock, salt, and—most notably—tuff at Yucca Mountain. The new political reality regarding Yucca Mountain may allow reconsideration of the decision to abandon research on shale as a repository host.
The Coastal Zone: A Mission Target for Satellite Altimeters
Authors: Cipollini Paolo , Vignudelli Stefano , Benveniste Jérôme
Published: February 2014

Synthetic aperture radar (SAR) altimetry is rapidly becoming the most efficient way to measure small‐scale changes in elevations of ice, land, and water surfaces as well as sea ice thickness. This new generation altimeter, first launched on board the CryoSat‐2 satellite, fires 10 times more radar pulses per second than the previous generation and exploits the motion of the spacecraft to achieve a 20‐fold increase in along‐track resolution and twofold improvement in its accuracy.
Celebrating the Power of Science
Authors: Finn Carol
Published: February 2014

Have you ever stopped to think about what AGU's more than 62,000 members represent? With a crowd that large, there's bound to be some variety, right?
Climate Scientists Build Relationships With Legislators
Authors: Hankin Erik
Published: February 2014

Forty climate scientists ventured to Washington, D. C., on 29 January 2014 for the fourth annual Climate Science Day on Capitol Hill. AGU, along with 13 other scientific societies, including the Geological Society of America and the American Chemical Society, invited members at the forefront of climate science, with communications expertise, to meet with their legislators. Through this event, the organizers facilitated more than 100 congressional meetings over the course of the day.
Bioactive Supramolecular Peptide Nanofibers for Regenerative Medicine
Authors: Arslan Elif , Garip I. Ceren , Gulseren Gulcihan , Tekinay Ayse B. , Guler Mustafa O.
Published: February 2014

Recent advances in understanding of cell–matrix interactions and the role of the extracellular matrix (ECM) in regulation of cellular behavior have created new perspectives for regenerative medicine. Supramolecular peptide nanofiber systems have been used as synthetic scaffolds in regenerative medicine applications due to their tailorable properties and ability to mimic ECM proteins. Through designed bioactive epitopes, peptide nanofiber systems provide biomolecular recognition sites that can trigger specific interactions with cell surface receptors. The present Review covers structural and biochemical properties of the self‐assembled peptide nanofibers for tissue regeneration, and highlights studies that investigate the ability of ECM mimetic peptides to alter cellular behavior including cell adhesion, proliferation, and/or differentiation.
Nanomechanical and Charge Transport Properties of Two‐Dimensional Atomic Sheets
Authors: Park Jeong Y. , Kwon Sangku , Kim Jong Hun
Published: February 2014

The materials properties of graphene and other two‐dimensional atomic sheets are influenced by atomic‐scale defects, mechanical deformation, and microstructures. Thus, for graphene‐based applications, it is essential to uncover the roles of atomic‐scale defects and domain structures of two‐dimensional layers in charge transport properties. This review highlights recent studies of nanomechanical and charge transport properties of two‐dimensional atomic sheets, including graphene, MoS2, and boron nitrides. Because of intrinsic structural differences, two‐dimensional atomic sheets give rise to unique nanomechanical properties, including a dependence on layer thickness and chemical modification that is in contrast to three‐dimensional continuum media. Mapping of local conductance and nanomechanical properties on a graphene layer can be used to image the domain and microstructures of two‐dimensional atomic layers. This paper also reviews recent experimental and theoretical findings on the role of bending, defects, and microstructures on nanomechanical and transport properties of graphene‐derived materials.
Preparation and performance evaluation of composite hollow fiber membrane for SO2 separation
Authors: Kim KeeHong , Hong SeongUk , Kim JongHak , Lee HyungKeun
Published: February 2014

Emission of sulfur dioxide (SO2) from coal power plants has to be controlled and minimized to reduce environmental risk. This study aimed to investigate the hollow fiber composite membrane was used for the removal of SO2 from a SO2/CO2/N2 mixed gas. Moreover, for the improvement of SO2 removal efficiency, the polyetherimide (PEI) membrane was coated with poly(vinyl chloride)‐graft‐poly(oxyethylene methacrylate) (PVC‐g‐POEM). The PVC‐g‐POEM/PEI composite hollow fiber membrane was extensively characterized by various techniques including scanning electron microscopy, Fourier transform infrared spectroscopy, and atomic force microscopy. Experiments with permeation of SO2, CO2, N2, and a ternary gas mixture were carried out to observe membrane behavior in response to different operating conditions. As a result, permeance of SO2 was 105–2705 GPU and selectivity of SO2/CO2 was 3.9–175.6. From the mixed gas separation experiment, the maximum SO2 removal efficiency reached up to 84.5%. © 2014 American Institute of Chemical Engineers AIChE J, 60: 2298–2306, 2014
Separation of acetic acid from dilute aqueous solution by nanofiltration membrane
Authors: Baruah Kundan , Hazarika Swapnali
Published: February 2014

NF membranes have been prepared from α, β, γ‐cyclodextrin (CD) composite with polysulfone and characterized by pore size, thickness, pure water permeability, contact angle measurement and membrane morphology study. The permeation performances of the prepared membranes have been tested for separation of acetic acid from dilute aqueous solution. Effect of concentration, pressure, flow rate on flux and rejection have been calculated and interpreted. Different permeation models have been tested for experimental values and validated by comparing the values with the experimental data. It has observed that in β‐CD membranes 99% recovery of acetic acid from aqueous solution has been obtained and found to be the best membrane for separation of acetic acid from dilute solution. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40537.
Distribution and environmental requirements of stream habitat with Ranunculion fluitantis and Callitricho‐Batrachion vegetation in lower Belgium (Flanders)
Authors: Leyssen An , Denys Luc , Schneiders Anik , Mouton Ans M.
Published: February 2014

Streams with Ranunculion fluitantis and Callitricho‐Batrachion vegetation – or habitat type 3260 according to the European Habitats Directive – require particular conservation at biogeographic level but Member States carry individual responsibility. Within this framework, the environmental requirements of this habitat type in lower Belgium (Flanders) were analysed.

Overall, current vegetation composition was not significantly related to adjacent land‐use but correlated mainly with physical–chemical conditions and to a lesser extent with distance to source and channel width. Even though sites with habitat 3260 generally showed lower levels of human impact, their abiotic features overlapped considerably with those of sites without habitat 3260 but still showing hydrophyte development.

Thresholds occurred in the distribution of responsive macrophyte taxa, including the more common characteristic species of the habitat type, along gradients of increasing solutes and nutrients. Comparison with water quality standards proposed so far to support good ecological status for the European Water Framework Directive in lowland rivers suggests that compliance would probably allow this habitat to persist in most cases, although some discrepancies occur. This implies that more stringent objectives may be required in some water bodies.

The present analysis focuses on the conditions delimiting occurrence of HT 3260, and therefore its range and area in lower Belgium. A comprehensive understanding of its favourable conservation status remains difficult in lowland regions where most rivers are subject to strong human impact and will require a more long‐term perspective that also considers management regime, physical habitat structure and connectivity.

Copyright © 2014 John Wiley & Sons, Ltd.
Students' group work strategies in source‐based writing assignments
Authors: Sormunen Eero , Tanni Mikko , Alamettälä Tuulikki , Heinström Jannica
Published: February 2014

Source‐based writing assignments conducted by groups of students are a common learning task used in information literacy instruction. The fundamental assumption in group assignments is that students' collaboration substantially enhances their learning. The present study focused on the group work strategies adopted by upper secondary school students in source‐based writing assignments. Seventeen groups authored Wikipedia or Wikipedia‐style articles and were interviewed during and after the assignment. Group work strategies were analyzed in 6 activities: planning, searching, assessing sources, reading, writing, and editing. The students used 2 cooperative strategies: delegation and division of work, and 2 collaborative strategies: pair and group collaboration. Division of work into independently conducted parts was the most popular group work strategy. Also group collaboration, where students worked together to complete an activity, was commonly applied. Division of work was justified by efficiency in completing the project and by ease of control in the fair division of contributions. The motivation behind collaboration was related to quality issues and shared responsibility. We suggest that the present designs of learning tasks lead students to avoid collaboration, increasing the risk of low learning outcomes in information literacy instruction.
Data, information, knowledge: An information science analysis
Authors: Badia Antonio
Published: February 2014

I analyze the text of an article that appeared in this journal in 2007 that published the results of a questionnaire in which a number of experts were asked to define the concepts of data, information, and knowledge. I apply standard information retrieval techniques to build a list of the most frequent terms in each set of definitions. I then apply information extraction techniques to analyze how the top terms are used in the definitions. As a result, I draw data‐driven conclusions about the aggregate opinion of the experts. I contrast this with the original analysis of the data to provide readers with an alternative viewpoint on what the data tell us.
Role of positions e and g in the fibrous assembly formation of an amphipathic α‐helix‐forming polypeptide
Authors: Takei Toshiaki , Tsumoto Kouhei , Yoshino Masakuni , Kojima Shuichi , Yazaki Kazumori , Ueda Takuya , Takei Tsunetomo , Arisaka Fumio , Miura Kin‐ichiro
Published: February 2014

We previously characterized α3, a polypeptide that has a three times repeated sequence of seven amino acids (abcdefg: LETLAKA) and forms fibrous assemblies composed of amphipathic α‐helices. Upon comparison of the amino acid sequences of α3 with other α‐helix forming polypeptides, we proposed that the fibrous assemblies were formed due to the alanine (Ala) residues at positions e and g. Here, we characterized seven α3 analog polypeptides with serine (Ser), glycine (Gly), or charged residues substituted for Ala at positions e and g. The α‐helix forming abilities of the substituted polypeptides were less than that of α3. The polypeptides with amino acid substitutions at position g and the polypeptide KEα3, in which Ala was substituted with charged amino acids, formed few fibrous assemblies. In contrast, polypeptides with Ala replaced by Ser at position e formed β‐sheets under several conditions. These results show that Ala residues at position e and particularly at position g are involved in the formation of fibrous assemblies. © 2014 Wiley Periodicals, Inc. Biopolymers (Pept Sci) 102: 260–272, 2014.
Synthesis and Conformational Analysis of Cyclic Homooligomers from Pyranoid ε‐Sugar Amino Acids
Authors: Feher‐Voelger Andrés , Borges‐González Jorge , Carrillo Romen , Morales Ezequiel Q. , González‐Platas Javier , Martín Tomás
Published: February 2014

New pyranoid ε‐sugar amino acids were designed as building blocks, in which the carboxylic acid and the amine groups were placed in positions C2 and C3 with respect to the tetrahydropyran oxygen atom. By using standard solution‐phase coupling procedures, cyclic homooligomers containing pyranoid ε‐sugar amino acids were synthesized. Conformation analysis was performed by using NMR spectroscopic experiments, FTIR spectroscopic studies, X‐ray analysis, and a theoretical conformation search. These studies reveal that the presence of a methoxy group in the position C4 of the pyran ring produces an important structural change in the cyclodipeptides. When the methoxy groups are present, the structure collapses through interresidue hydrogen bonds between the oxygen atoms of the pyran ring and the amide protons. However, when the cyclodipeptide lacks the methoxy groups, a U‐shape structure is adopted, in which there is a hydrophilic concave face with four oxygen atoms and two amide protons directed toward the center of the cavity. Additionally, we found important evidence of the key role played by weak electrostatic interactions, such as the five‐membered hydrogen‐bonded pseudocycles (C5) between the amide protons and the ether oxygen atoms, in the conformation equilibrium of the macrocycles and in the cyclization step of the cyclic tetrapeptides.
Synthesis and Structure of Tetraethynylsilane and Its Silylated Derivatives
Authors: Geyer Florian L. , Rominger Frank , Bunz Uwe H. F.
Published: February 2014

The known tetrakis((trimethylsilyl)ethynyl)silane was prepared and deprotected. By using trifluoromethanesulfonic acid, the smooth stepwise desilylation of the starting material was achieved, and all of the partially protected and the fully deprotected species were isolated by sublimation. Crystal structures of all of the partially and the fully deprotected species were obtained. None of the compounds is thermally sensitive. Attempts to explosively decompose these species upon heating failed.
New PN Cage Compounds Generated by Small‐Molecule Activation
Authors: Hinz Alexander , Schulz Axel , Villinger Alexander
Published: February 2014

The isolation of new small‐cage compounds consisting exclusively of Group 15 elements was achieved by exploiting the reactivity of diphosphadiazanediyls. These biradicaloids were used to activate small molecules containing double bonds, such as diazenes and in situ generated diphosphenes, leading to the formation of hexapnicta‐[2.1.1]bicyclohexanes.
Kinetics modelling of 2‐butene metathesis over tungsten oxide containing mesoporous silica catalyst
Authors: Bhuiyan Tazul I. , Arudra Palani , Hossain Mohammad M. , Akhtar Mohammad N. , Aitani Abdullah M. , Abudawoud Raed H. , Al‐Khattaf Sulaiman S.
Published: February 2014

This article reports the activity, reaction mechanism and reaction kinetics of 2‐butene metathesis over tungsten oxide containing mesoporous silica (SBA‐15) catalyst. Physicochemical characterisation of the catalyst indicates that the dispersion and nature of tungsten oxide species on the catalyst are mainly responsible for the metathesis activity. The ample availability of Brønsted acid sites created by tetrahedrally co‐ordinated tungsten species also enhances the metathesis reaction. The product analysis indicates that lower temperature favours the butene isomerisation, while higher temperature is required for metathesis. The high temperature is also responsible for cracking reactions. A kinetics model is developed based on the experimental observations and the possible reactions including isomerisation, metathesis and cracking. The model parameters are estimated by fitting the experimental data implemented in MATLAB. The estimated apparent activation energy of 2‐butene isomerisation reaction was found to be the lowest (39.4 kJ/mol) among the competing reactions. The activation energy of cross metathesis of 2‐butene and 1‐butene, self‐metathesis of 1‐butene and 2‐butene cracking are 71.3, 176.9 and 73.1 kJ/mol, respectively. These results are consistent to the product selectivity and the proposed reaction scheme, which suggests that the isomerisation of 2‐butene gives 1‐butene and it further reacts (cross metathesis) with 2‐butene to produce propylene.