bluuebunny/crossref_metadata_2025 huggingface dataset:
Sous quelles conditions construire, capitaliser et mobiliser des savoirs professionnels efficients en situation d’enseignement ? L’étude de cas d’un stagiaire
Authors: Baconnet Sophie
Published: September 2014

Cet article a pour visée de mieux comprendre comment se construit une expérience professionnelle efficiente pour un stagiaire professeur des écoles. Dans la présente publication, nous limitons notre étude à l’observation d’un stagiaire. La recherche a été menée au sein d’un dispositif de formation innovant actif durant trois ans de 2007 à 2009 à la FDE de Montpellier, appelé « atelier dirigé d’écriture ». Dispositif innovant car libérant le stagiaire du groupe-classe. L’autorisant à se focaliser sur un effectif réduit d’élèves dans le but de favoriser la prise en charge de leurs difficultés. Nous appuyons notre analyse sur le couplage de concepts clé comme la capacité à observer des élèves singuliers et le sentiment d’efficacité personnelle. Nous utilisons la méthode clinique de l’activité selon Clot et Faïta (2000) dans le but de repérer dans le discours post activité du stagiaire des indicateurs de professionnalisation suffisamment stabilisés dans la durée du dispositif (plusieurs mois de stage). Nous examinons sous quelles conditions ces savoirs d’expérience, qui se révèlent provisoires, se construisent dans le rejeu d’un dispositif jouant le rôle d’intégrateur de compétences professionnelles. Les résultats mettent en relief l’utilité de la conceptualisation dans l’action, concept clé en didactique professionnelle (Pastré, 1992). En effet, des règles d’action en cours d’élaboration chez le stagiaire et évolutives dans le temps renseignent sur le degré d’avancement des gestes de métier du formé. En dernier lieu, nous mettons ces résultats en débat, avant de conclure.
Agir et art de faire. Répercussions sur le développement identitaire des assistants sociaux
Authors: Glarner Thierry
Published: September 2014

L’assistant social forge son identité professionnelle dans son engagement à se mettre au service des populations exclues en vue d’améliorer leur sort. Cette identité professionnelle influence fortement son regard sur le monde et par conséquent, l’art de faire influence la construction identitaire. Lorsque les relations avec la hiérarchie, la population aidée ou l’environnement institutionnel défaillent, comment cette identité professionnelle est-elle perçue par l’assistant social et comment son identité personnelle se développe-t-elle avec le temps ? L’analyse de récits de pratiques d’assistants sociaux ayant vécu des situations de souffrances dans leur travail met en évidence les liens étroits entre assistant social, institution et population aidée. La nature affective des liens qui émerge de l’art de faire se démarque à travers les trois pôles et joue alors un rôle prépondérant sur le développement identitaire de l’intervenant.
L’abandon des études universitaires en formation à l’enseignement professionnel : un phénomène difficile à cerner
Authors: Tardif Marc , Deschenaux Frédéric
Published: September 2014

Au Québec, le phénomène de l’abandon des études universitaires a été peu étudié, particulièrement dans les baccalauréats en formation à l’enseignement professionnel de 120 crédits plus de dix ans après leur implantation. L’analyse secondaire des données issues de deux sources révèle que près d’une personne sur deux abandonne ses études dans ces programmes. Le contexte particulier dans lequel se retrouvent ces étudiants, une discussion des enjeux théoriques liés à l’abandon des études universitaires et un exposé des limites méthodologiques liées au calcul de ces indicateurs sont tour à tour abordés pour tenter de cerner ce phénomène aussi complexe que préoccupant.
En studentfest år 1777: om maktspel, vältalighet och förlustelser i Uppsala
Authors: Burman Lars
Published: September 2014

In 1777 new statutes were adopted at Östgöta nation, one of the mandatory student associations in Uppsala. In connection with this a lavish feast was arranged, which comprised both a dinner with invited university guests and an oration by one of the younger nation members. The orator was Carl Gustaf Leopold (1756-1829), who was later to become a member of the Swedish Academy. The article proposes that the festivities can be regarded as an attempt to further legitimize the nation organizations, and to make clear that the nations considered themselves as dependable and closely connected to the university. The consistory of the university hesitated to ratify the new statutes; the matter was not considered to be a question for the university. Östgöta nation, however, would later obtain a confirmation directly from the chancellor. The festivities were thus a symbolic manifestation and a method of persuasion. The goals and tactics can be inferred from the nation's memoranda books, but also from Leopold's oration. The article contains a rhetorical analysis of his argumentation. A facetious poem by the young docent Eric Michael Fant (1754-1817), who depicted the event and the ensuing revelries, throws light on the occasion. A complete transcription of the manuscript is included.
Columbia the Goddess of Liberty and Slave-Trade Abolition (1807–1820s)
Authors: Gibbs Jenna M.
Published: September 2014

Eighteenth-century American thespians, balladeers, and artists used performances of Columbia, an anthropomorphic metaphor for the body politic, to animate Enlightenment precepts of natural rights and liberty. Following the American Revolution, anti-slavery sympathizers staged Columbia as a symbol both of political liberty from Great Britain and of personal liberty in engravings, plays, and ballads that depicted her bequeathing freedom to Africans from the throne of her Temple. But in reaction to slave-trade abolition-Great Britain's 1807 legislation and the United States' ban in 1808-cultural producers began bifurcating constitutional from personal freedom in their iterations of Columbia. Anti-slavery advocates still used Columbia as an iconic syncretism of political and personal liberty to critique slavery. Others, however, threatened by the possibility of black freedom associated with slave-trade abolition, staged Columbia to represent political but not personal liberty. Thus, just as the slave-trade ban went into effect, Philadelphia's New Theater performed Columbia in dances, songs, and allegorical set pieces that fêted political independence, but in which slaves were absent, an erasure that reinforced whiteness as the defining qualification for American citizenship. Postabolition performances of Columbia in her Temple of Liberty, constructed on rigidifying edifices of racial codification, banished blacks from the civic polity-a far cry from Enlightenment precepts of liberty and rights.
En gruvkarls lott: om upplysningstendenser i 1720- och 1750-talens bröllopsdiktning
Authors: Hansson Stina
Published: September 2014

The article discusses new tendencies in eighteenth-century wedding poetry, tendencies which can briefly be described in terms of a backlash against fantastic storytelling and an orientation towards more realistic descriptions, often coupled with a deliberative rather than demonstrative rhetorical approach. The shift is demonstrated first through a broad survey of themes in Swedish wedding poetry from the seventeenth and eighteenth centuries, and then through analyses focusing on two poems of the new kind which thematize the groom's profession through descriptions of mining work astonishingly ‘realistic' for the time. The main explanation for this is that there were no venerated models to follow when writing about these themes, as well as the fact that the poems were not written for public but for private use. The poems are then compared with other poems from the same mining area, but with learned themes more typical of the wedding poetry of the time. It is then concluded that Swedish poets still had a long way to go to be able to incorporate such ‘realistic' features into the conception of what ‘poetry' was considered to look like.
Vaucanson’s Automata as Devices of Enlightenment
Authors: Landes Joan B.
Published: September 2014

Residing at the interstices of high and low culture, pleasure and utility, wonder and technique, Vaucanson's automata belonged to what historian Michael R. Lynn refers to as ‘a growing web of interconnections between Enlightenment, science, and commerce in Parisian urban culture'. While the wider public attraction to automata during the eighteenth-century has been noted, it is also necessary to address the nature of this appeal, which is derived from the automata's simulation of the workings of human and animal bodies. Vaucanson was one of a number of astonishingly brilliant eighteenth-century mechanicians, who attempted to design material bodies capable of artificially replicating life. Their ingenious machines were indeed devices of Enlightenment, that is, philosophically animated experimental objects. The aim of these devices was to approximate what contemporaries like Diderot referred to as a ‘sentient being' with a particular spatial and dynamic organization. Over time, then, automata makers were challenged to imitate not just the body's mechanics but also the workings of the senses, to capture emotion as well as motion.
En revolution i offentligheten: om lärda tidskrifter i Europa under tidigmodern tid och om hur svensk vetenskap representerades i dem
Authors: Oscarsson Ingemar
Published: September 2014

The birth and rapid progress of scientific periodicals during the closing decades of the seventeenth century was a process that entailed new challenges for scholars and had many implications for the relations between the republic of letters and society as a whole. From this point forward, stronger demands were placed upon scholars to publicly account for their findings, as well as to improve their ability to communicate their research to a general audience. Inherent in this process was the gradual development of a new genre, the modern scientific article, together with spin-off forms like reviews, summaries, and abstracts. In Sweden, the quarterly Acta literaria Sueciæ (Uppsala, 1720-1729) was pioneering in its ambition to give Swedish scholarship a more conspicuous place in the learned world than it had been bestowed in foreign journals. In this the Latin Acta did experience some success, but a more comprehensive breakthrough for Swedish learning in the European media came during the next few decades, reflecting the country's prosperity in the natural sciences. Of vital importance for this breakthrough was, beginning in 1739, the quarterly Handlingar (written in the vernacular) of the Royal Swedish Academy of Sciences, which was extensively translated and reviewed abroad. In the francophone sphere, however, its reception lagged in comparison to what was the case in the German area, and in the renowned Journal des savants, the Swedish journal was practically disregarded for many years. Then, in the 1770s and 1780s, it unexpectedly became the subject of a rather intense series of reviews composed by French intermediaries who took pains to learn Swedish. The article concludes with several examples of their techniques for transmitting the contents of Handlingar through the use of summaries, paraphrases, and translations.
Böckernas vägar: den svenska bokhandelns import av utländska böcker 1750–1800
Authors: Rimm Anna-Maria
Published: September 2014

This study focuses on the import of books to Sweden between 1750 and 1800. The Swedish book trade in the eighteenth century involved mainly foreign books. The publication of books in Swedish was still limited - despite increasing steadily during the century - and was in no way able to satisfy the needs of Swedish scholars for learned and diverting works in their original language. The import of foreign books to Sweden seems to have been undertaken in various ways: with the help of individuals who brought books home with them from abroad, through the universities' exchange of scholarly works with institutions overseas, and by means of the organized book trade. Several Swedish book sellers imported books from abroad during the latter part of the eighteenth century. In fact, Sweden had a substantial number of book shops compared with other European cities. In the 1781 European bookseller's directory, the Almanach de la librairie, Stockholm shared fifth place (with The Hague) in a ranking of European cities with the largest number of book shops, placing higher than cities such as Berlin, Amsterdam, Madrid, and Rome. Importing books to Sweden was, however, a financially risky business and some of the importers went bankrupt because of it. The conditions of the trade also underwent marked developments during the period studied: originally, for example, imports largely took the form of exchanges. In conclusion, the article shows that more basic research and comprehensive empirical studies need to be undertaken to provide a fair picture of this hitherto largely unresearched trade.
Mozarts musikaliska retorik: en studie av musikaliskt avbildande element i Mozarts operor
Authors: Tråvén Marianne
Published: September 2014

This article investigates and describes the components of Wolfgang Amadeus Mozart's musical rhetoric as they are visible in his operas from Zaide (1780) to Die Zauberflöte (1791). The relationship between verbal text and musical text is in these operas especially intimate, and Mozart used the musical text to illustrate, paint and comment the verbal text. Mozart's views on the compositional process, visible in his letters, rested on the notion that music should portray the characters, emotional content and action of the play, all within the harmonic laws of the time. To achieve that he used a combination of traditional musical rhetoric figures, conventions understood by his contemporaries, paralinguistic elements such as emotional prosody, and extralinguistic elements such as musical gesture, to portray actions and objects as well as concepts.
The Political Economy of Colonisation: Carl Bernhard Wadström’s Case for Abolition and Civilisation
Authors: Ahlskog Jonas
Published: September 2014

This article is an analysis of the Swedish abolitionist and Swedenborgian Carl Bernhard Wadström’s (1746–1799) writings in the British anti-slavery debate in the years between 1788 and 1795. Previous historical scholarship has seen Wadström primarily as a Swedenborgian visionary on a quest for religious fulfilment in Africa. An alternative perspective on Wadström’s writings is offered in this article by highlighting his comparatively overlooked polemical publications and Parliamentary testimonies in the British anti-slavery debate. Instead of treating Wadström’s writings and colonial plans as manifestations of his Swedenborgian dreams, they are reassessed as contributions to the contemporary anti-slavery debate. The focus is on how Wadström participated and argued in this debate in order to show the ideological tenets underlying his views. Wadström is linked to the Scottish Enlightenment discourse by showing how he uses the concepts of classical political economy in his argumentation for the abolition of the Atlantic slave trade. Through this alternative reading of Wadström’s writings, it is possible to gain another entry point into the complex and motley character of late eighteenth-century political thought in Northern Europe.
Voltaire’s Valet: The Career of Sebastian G. Longchamps from Servant to Map Publisher
Authors: Reitinger Franz
Published: September 2014

Sebastian G. Longchamps (1718–1793) is a well-established figure among the variety of minds who gathered around Voltaire. Longchamps’s recollections are the major surviving source of information for Voltaire’s Cirey period. Given the immense body of literature dedicated to Voltaire’s life and work, however, no serious attempt to enquire into the disappearance of his long-term ‘shadow’ has been made. This has led to the paradoxical situation that Longchamp’s, or more accurately, Longchamps’s personality has been split into two identities. Literary scholars have long been familiar with the Memoires of Voltaire’s servant Longchamp. Map historians, in turn, have come across numerous maps by a somewhat obscure publisher named Longchamps. The confusion was made complete by the uncertainties caused from the different versions of Longchamps’s first and last names. At the root of this confusion was a legal investigation instituted by Voltaire’s niece, Madame Denis, which, although only a short anecdote in Voltaire’s biography, had a significant impact on Longchamps’s life. This article attempts to take a closer look at the metamorphosis that Longchamps’s personality underwent in order to highlight some of his principal motives, incentives and constraints.

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Drømmen om Sydhavet: Biopolitik og seksualitet i Denis Diderots Supplément au voyage de Bougainville
Authors: Fastrup Anne , Eliassen Knut Ove
Published: September 2014

The Dream of the Pacific: Bio-Politics and Sexuality in Denis Diderot’s Supplément au voyage de Bougainville

An important issue in the economic debates of the eighteenth century was the concern that the advanced Europeans nations were facing a decline in population. It was assumed that this would have considerable consequences for the economic and military strength of countries like France and England. The idea that the decline was an effect of the European countries’ advanced state of civilisation was widespread; accordingly, explorers like James Cook and Louis Antoine de Bougainville were eager to examine the ways in which the societies and cultures they encountered organised sexual reproduction. Informed by the travelers’ accounts, and recognising the possible insights these offered for the challenges France was facing, Denis Diderot’s Supplément au voyage de Bougainville analyses and discusses the sexual mores of the inhabitants of Tahiti. Taking as its starting point the oblique and slightly idiosyncratic way in which the French philosopher addresses the issue — in the form of an apocryphal “supplement” to Bougainville’s account supposedly written by the explorer himself — this essay analyses the way in which Diderot transforms an ethnographic reflection on Polynesian culture into an analysis of the pathologies of his contemporary France from the double perspective of economy and ethics.
The Peace Treaty of Fredrikshamn and its Aftermath in Sweden and Finland
Authors: Karonen Petri
Published: September 2014

This article analyses the Peace Treaty of Fredrikshamn (Hamina in Finnish) and its consequences in Sweden and Finland. The Russians set strict preconditions for the commencement of peace negotiations with the Swedes in the summer of 1809. These conditions were realized almost in toto in the final peace treaty, which consisted of just twenty-one articles. In addition to regulations directly related to the ending of hostilities, the main provisions of the agreement entailed huge territorial losses for Sweden, strictly defining the regions it was to cede to Russia, the most important of which was Finland. Sweden was also enjoined to give up its alliance with Britain and to join the Continental Blockade. Furthermore, the peace treaty laid down provisions for securing the position of both Finns and Swedes as subjects in the new situation, defined measures to ensure the continued functioning of the economy, and stipulated strict provi- sions for the protection of private property. The latter were very significant, especially with regard to the legitimacy of the administration, the pacification of society, and the safeguarding of the infrastructures in both Finland and Sweden. The post-war resumption of peace was not easy for either the Finns or the Swedes. However, the problems caused by the peace treaty were very different on the two sides of the Gulf of Bothnia. The problems in Finland were easier to solve because they were more concrete. The Grand Duchy of Finland, which was born out of the treaty, was permitted to maintain the existing Swedish legislative, social and local administrative framework, and a new central governmental machinery was created on top of it. In Sweden, the most important problems attending the return to peace (which could also be described as a ‘crisis of peace’) included the difficult question of the succession along with serious internal and economic issues. However, the most serious worry concerned the re-establishment and maintenance of the legitimacy of the government in the new situation.
Tessinarna i Venedig
Authors: Olin Martin
Published: September 2014

The Tessins in Venice

Foreign royalty and other travelers visiting Venice in the early eighteenth century encountered a flourishing of the arts. This vibrant artistic life could be transposed to new settings, as a number of Venetian painters worked for courts north of the Alps. When the statesman and connoisseur Carl Gustaf Tessin, Swedish Ambassador to Vienna, visited Venice in 1736, it was with the intention of hiring a decorative painter for the new royal palace in Stockholm. His first choice was Giovanni Battista Tiepolo, but his services proved to be too costly for the Swedes. Tessin did, however, buy art works, among them easel paintings by Tiepolo, Giuseppe Nogari and Francesco Zuccarelli. Anton Maria Zanetti helped Tessin survey the artistic landscape of his city and later became his agent. Carl Gustaf Tessin was not the first Tessin in Venice. His father and grandfather had also visited and documented Venetian architecture in drawings and notes. Marble floors in Venetian buildings left such a lasting impression on Nicodemus Tessin the Elder that he incorporated their patterns in his floor designs for Drottningholm Palace. In his travel notes from 1688, Nicodemus Tessin the Younger is critical of Venetian architecture, but writes enthusiastically about the city’s theatre and civic life.
« Manuscrit de Mr Dangicourt » : système métaphysique néantiste d’un disciple de Leibniz
Authors: Kaitaro Timo
Published: September 2014

Dangicourt’s Manuscript: The metaphysical system of nothingness from a disciple of Leibniz

The collection of clandestine philosophical manuscripts at the Helsinki University Library contains, among other typical seventeenth and early eighteenth century texts, an exchange of letters between Pierre Dangicourt and Alphonse Des Vignoles (1725−1726). Both belong to the circle of thinkers close to the Academy of Sciences in Berlin. Starting from some mathematical conjectures concerning the incommensurability of the sides and the diagonal of a geometrical square, Dangicourt develops a metaphysical system according to which ‘original material’ (la matière originale) of the universe is ‘nothingness’ (néant) and criticises the view according to which the universe consists of extended and existing composite parts. Des Vignoles presents a criticism of Dangicourt’s ideas. In a letter to Dangicourt, Leibniz also presents criticisms of Dangcourt’s system by insisting on the fictional nature of mathematical abstractions.
The Rehabilitation of Myth: Enlightenment and Romanticism in Johann Gottfried Herder’s Vom Geist der Ebräischen Poesie
Authors: Steinby Liisa
Published: September 2014

In literary, cultural and historical study of mythology, Johann Gottfried Herder is often portrayed as the bridge between the Enlightenment and the Romantic age. Myths for Herder were not only material for poetry, but the essential content of religion. Herder’s new understanding of myth and religion did not, however, signify a rejection of the Enlightenment principle of rationality. On the contrary, this understanding expanded and transformed his understanding of rationality. Herder regarded man’s mythopoetic activity as a genuine and natural form of man’s cognitive appropriation of the world. The personification of natural forces in the cultural creation of gods did not denote a return to irrationalism, but an extended form of rationality. According to Herder, the Bible had to be read as a human mythopoetic creation. The Old Testament, which depicts the special relation of God to His people, was in Herder’s Vom Geist der ebräischen Poesie (1782–1783) the result of a poetic worldview characteristic of nomadic societies. Herder did question the validity of the Old Testament as a true source of religion and its usefulness even for modern man. Mythology did not have to be rejected as untrue imagination. Old Testament monotheism could be related to Spinoza’s pantheism and the Law of Moses could be seen as a precursor of the modern constitutional tradition.
Tacksägelser, troféer och en talmans död: politiska ceremonier och scener under krigsåren 1788–1790
Authors: Tandefelt Henrika
Published: September 2014

[no abstract]
Carl PeterThunbergs japanska resa i 1770- och 1780-talens medier
Authors: Skuncke Marie-Christine
Published: September 2014

[no abstract]
Känsla som kunskap: poesi och historia i Robert Lowths De sacra poesi Hebraeorum
Authors: Cullhed Anna
Published: September 2014

[no abstract]
Gate-on-germanium source tunnel field-effect transistor enabling sub-0.5-V operation
Authors: Mallik Abhijit , Chattopadhyay Avik , Omura Yasuhisa
Published: September 2014

In this paper, a novel device structure for a gate-on-germanium source (GoGeS) tunnel field-effect transistor (TFET) on a bulk silicon substrate is proposed for sub-0.5-V operation. Tunneling in line with the gate electric field, which increases the effective tunneling area and, hence, the ON-state current (I
ON) is achieved in this device by constructing its gate on the germanium source region. To improve the subthreshold swing (SS), lateral carrier tunneling is eliminated by carefully designing the device structure. The use of a small gate-to-channel overlap results in reduced fringing-induced barrier lowering at the gate edge that further improves the SS and I
ON of the device. The spreading of the fringing electric field is also reduced by employing a step in the silicon channel region, which again improves both SS and I
ON. As a result of all these, supersteep SS and high I
ON are achieved, enabling sub-0.5-V operation of the proposed GoGeS TFET.
Low‐mid latitude D region ionospheric perturbations associated with 22 July 2009 total solar eclipse: Wave‐like signatures inferred from VLF observations
Authors: Maurya Ajeet K. , Phanikumar D. V. , Singh Rajesh , Kumar Sushil , Veenadhari B. , Kwak Y.‐S. , Kumar Abhikesh , Singh Abhay K. , Niranjan Kumar K.
Published: September 2014

We present first report on the periodic wave‐like signatures (WLS) in the D region ionosphere during 22 July 2009 total solar eclipse using JJI, Japan, very low frequency (VLF) navigational transmitter signal (22.2 kHz) observations at stations, Allahabad, Varanasi and Nainital in Indian Sector, Busan in Korea, and Suva in Fiji. The signal amplitude increased on 22 July by about 6 and 7 dB at Allahabad and Varanasi and decreased by about 2.7, 3.5, and 0.5 dB at Nainital, Busan, and Suva, respectively, as compared to 24 July 2009 (normal day). The increase/decrease in the amplitude can be understood in terms of modal interference at the sites of modes converted at the discontinuity created by the eclipse intercepting the different transmitter‐receiver great circle paths. The wavelet analysis shows the presence of WLS of period ~16–40 min at stations under total eclipse and of period ~30–80 min at stations under partial eclipse (~85–54% totality) with delay times between ~50 and 100 min at different stations. The intensity of WLS was maximum for paths in the partially eclipsed region and minimum in the fully eclipsed region. The features of WLS on eclipse day seem almost similar to WLS observed in the nighttime of normal days (e.g., 24 July 2009). The WLS could be generated by sudden cutoff of the photo‐ionization creating nighttime like conditions in the D region ionosphere and solar eclipse induced gravity waves coming to ionosphere from below and above. The present observations shed additional light on the current understanding of gravity waves induced D region ionospheric perturbations.
Wave number determination of Pc 1–2 mantle waves considering He++ ions: A Cluster study
Authors: Grison B. , Escoubet C. P. , Santolík O. , Cornilleau‐Wehrlin N. , Khotyaintsev Y.
Published: September 2014

The present case study concerns narrowband electromagnetic emission detected in the distant cusp region simultaneously with upgoing plasma flows. The wave properties match the usual properties of the Pc 1–2 mantle waves: small angle between the wave vector and the magnetic field line, left‐hand polarization, and propagation toward the ionosphere. We report here the first direct wave vector measurement of these waves (about 1.2 × 10− 2 rad/km) through multi spacecraft analysis using the three magnetic components and, at the same time, through single spacecraft analysis based on the refractive index analysis using the three magnetic components and two electric components. The refractive index analysis offers a simple way to estimate wave numbers in this frequency range. Numerical calculations are performed under the observed plasma conditions. The obtained results show that the ion distribution functions are unstable to ion cyclotron instability at the observed wave vector value, due to the large ion temperature anisotropy. We thus show that these electromagnetic ion cyclotron (EMIC) waves are amplified in the distant cusp region. The Poynting flux of the waves is counterstreaming with respect to the plasma flow. This sense of propagation is consistent with the time necessary to amplify the emissions to the observed level. We point out the role of the wave damping at the He++ gyrofrequency to explain that such waves cannot be observed from the ground at the cusp foot print location.
On the threshold energization of radiation belt electrons by double layers
Authors: Osmane A. , Pulkkinen T. I.
Published: September 2014

Using a Hamiltonian approach, we quantify the energization threshold of electrons interacting with radiation belts' double layers discovered by Mozer et al. (2013). We find that double layers with electric field amplitude E0 ranging between 10 and 100 mV/m and spatial scales of the order of few Debye lengths are very efficient in energizing electrons with initial velocities v∥ ≤ vth to 1 keV levels but are unable to energize electrons with E ≥ 100 keV. Our results indicate that the localized electric field associated with the double layers are unlikely to generate a seed population of 100 keV necessary for a plethora of relativistic acceleration mechanisms and additional transport to higher energetic levels.
Influence of precipitating energetic ions caused by EMIC waves on the subauroral ionospheric E region during a geomagnetic storm
Authors: Yuan Zhigang , Xiong Ying , Li Haimeng , Huang Shiyong , Qiao Zheng , Wang Zhenzhen , Zhou Meng , Wang Dedong , Deng Xiaohua , Raita Tero , Wang Jingfang
Published: September 2014

In this paper, we have presented the influence of precipitating energetic ions caused by electromagnetic ion cyclotron (EMIC) waves on the subauroral ionospheric E region during a geomagnetic storm on 8 March 2008 with observations of the Meteorological Operational (METOP‐02) of the Polar Orbiting Environmental Satellites (POES), a GPS receiver in Vaasa of Finland and Finnish network of search coil magnetometers. Conjugate observations of the POES METOP‐02 satellite and Finnish network of search coil magnetometers have demonstrated that enhancements of the precipitating energetic ion flux within the proton anisotropic zone are attributed to the interaction between ring current (RC) ions and EMIC waves. With enhancements of the intensity of Pc1 waves observed by search coil magnetometers, the total electron content observed by the GPS receiver accordingly increased, meaning that the enhancement of the ionospheric electron density is attributed to the precipitation of RC ions caused by EMIC waves. The electron density profiles derived by the International Reference Ionosphere (IRI‐2007) model and with precipitating energetic protons observed by the POES METOP‐02 satellite show that the energetic proton precipitation can cause the E layer peak electron density to increase from 1.62 × 109 m−3 to 5.05 × 1011 m−3 by 2.49 orders of magnitude. In comparison with the height‐integrated conductivities derived by the IRI‐2007 model, the height‐integrated Pedersen and Hall conductivities derived with precipitating energetic protons increase by 2.4 and 2.34 orders of magnitude, respectively. Our result suggests that precipitating energetic ions caused by EMIC waves can lead to an obvious enhancement of the electron density and conductivities in the subauroral ionospheric E region during geomagnetic storms.
Circum‐Arctic mantle structure and long‐wavelength topography since the Jurassic
Authors: Shephard G. E. , Flament N. , Williams S. , Seton M. , Gurnis M. , Müller R. D.
Published: September 2014

The circum‐Arctic is one of the most tectonically complex regions of the world, shaped by a history of ocean basin opening and closure since the Early Jurassic. The region is characterized by contemporaneous large‐scale Cenozoic exhumation extending from Alaska to the Atlantic, but its driving force is unknown. We show that the mantle flow associated with subducted slabs of the South Anuyi, Mongol‐Okhotsk, and Panthalassa oceans have imparted long‐wavelength deflection on overriding plates. We identify the Jurassic‐Cretaceous South Anuyi slab under present‐day Greenland in seismic tomography and numerical mantle flow models. Under North America, we propose the “Farallon” slab results from Andean‐style ocean‐continent convergence around ~30°N and from a combination of ocean‐continent and intraoceanic subduction north of 50°N. We compute circum‐Arctic dynamic topography through time from subduction‐driven convection models and find that slabs have imparted on average <1–16 m/Myr of dynamic subsidence across the region from at least 170 Ma to ~50 Ma. With the exception of Siberia, the main phase of circum‐Arctic dynamic subsidence has been followed either by slowed subsidence or by uplift of <1–6 m/Myr on average to present day. Comparing these results to geological inferences suggest that subduction‐driven dynamic topography can account for rapid Middle to Late Jurassic subsidence in the Slave Craton and North Slope (respectively, <15 and 21 m/Myr, between 170 and 130 Ma) and for dynamic subsidence (<7 m/Myr, ~170–50 Ma) followed by dynamic uplift (<6 m/Myr since 50 Ma) of the Barents Sea region. Combining detailed kinematic reconstructions with geodynamic modeling and key geological observations constitutes a powerful tool to investigate the origin of vertical motion in remote regions.
Assimilation of point SWE data into a distributed snow cover model comparing two contrasting methods
Authors: Magnusson Jan , Gustafsson David , Hüsler Fabia , Jonas Tobias
Published: September 2014

In alpine and high‐latitude regions, water resource decision making often requires large‐scale estimates of snow amounts and melt rates. Such estimates are available through distributed snow models which in some situations can be improved by assimilation of remote sensing observations. However, in regions with frequent cloud cover, complex topography, or large snow amounts satellite observations may feature information of limited quality. In this study, we examine whether assimilation of snow water equivalent (SWE) data from ground observations can improve model simulations in a region largely lacking reliable remote sensing observations. We combine the model output with the point data using three‐dimensional sequential data assimilation methods, the ensemble Kalman filter, and statistical interpolation. The filter performance was assessed by comparing the simulation results against observed SWE and snow‐covered fraction. We find that a method which assimilates fluxes (snowfall and melt rates computed from SWE) showed higher model performance than a control simulation not utilizing the filter algorithms. However, an alternative approach for updating the model results using the SWE data directly did not show a significantly higher performance than the control simulation. The results show that three‐dimensional data assimilation methods can be useful for transferring information from point snow observations to the distributed snow model.
A new formulation for steady multiaquifer flow: An analytic element for piecewise constant infiltration
Authors: Strack O. D. L. , Namazi Taha
Published: September 2014

This paper contains a new formulation for infiltration inside domains bounded by polygons and its application to problems of steady multiaquifer flow, using the Dupuit‐Forchheimer approximation and assuming vertical flow in the separating layers. An alternative formulation is presented for leaky aquifer systems where infiltration or extraction is given. Existing formulations of multiaquifer flow involve a system of equations that must be solved for the heads in the aquifers. These formulations are abstract, and the relation between the parameters in the solution and physical quantities is hidden. The formulation in the paper aims at linking the system of equations to physical quantities; we have done this in two ways. First, we formulate the problem in terms of leakage potentials, related directly to the leakage through the leaky layers. Second, we introduce the concept of “equilibrated leakage,” leakage that is either the result of infiltration or of some disturbance in the flow pattern, such as that caused by a well. The leakage through the leaky layers tends to some constant value far from a disturbance, e.g., a well, or the boundary of an area of constant infiltration. This concept of equilibrated leakage is useful in practice and helps in understanding the distribution of leakage; we explain this in detail in the paper. The study of problems of steady flow in leaky aquifer systems is inspired by problems of groundwater sustainability, where the overall distribution of flow over long periods of time is important, rather than detailed information.
A Biocompatible “Split Luciferin” Reaction and Its Application for Non‐Invasive Bioluminescent Imaging of Protease Activity in Living Animals
Authors: Godinat Aurélien , Budin Ghyslain , Morales Alma R. , Park Hyo Min , Sanman Laura E. , Bogyo Matthew , Yu Allen , Stahl Andreas , Dubikovskaya Elena A.
Published: September 2014

The great complexity of many human pathologies, such as cancer, diabetes, and neurodegenerative diseases, requires new tools for studies of biological processes on the whole organism level. The discovery of novel biocompatible reactions has tremendously advanced our understanding of basic biology; however, no efficient tools exist for real‐time non‐invasive imaging of many human proteases that play very important roles in multiple human disorders. We recently reported that the “split luciferin” biocompatible reaction represents a valuable tool for evaluation of protease activity directly in living animals using bioluminescence imaging (BLI). Since BLI is the most sensitive in vivo imaging modality known to date, this method can be widely applied for the evaluation of the activity of multiple proteases, as well as identification of their new peptide‐specific substrates. In this unit, we describe several applications of this “split luciferin” reaction for quantification of protease activities in test tube assays and living animals. Curr. Protoc. Chem. Biol. 6:169‐189 © 2014 by John Wiley & Sons, Inc.
Evaluation of Compounds in Primary Human Islet Cell Culture
Authors: Walpita Deepika , Wagner Bridget K.
Published: September 2014

The identification of novel small molecules that promote pancreatic beta‐cell proliferation is an important approach to therapeutic discovery for diabetes. Because human islets are not easy to culture, and attach poorly to plates, it had not been feasible to run high‐throughput phenotypic assays in these cells. Therefore, most laboratories have turned to rodent islets for ease of culture and accessibility. However, rodent islets are not physiologically similar to human islets, either in terms of islet architecture or endocrine cell interactions within the islet, and data generated in rodent islets do not typically translate to human islet biology. To address this challenge, we developed a human islet culture system for high‐throughput screening using a thymidine analog, EdU, to detect beta‐cell replication during screening. Simultaneous monitoring of EdU incorporation and beta cell numbers provides a robust assay for beta‐cell replication, and is now becoming a standard protocol enabling screening in human islets. Curr. Protoc. Chem. Biol. 6:157‐168 © 2014 by John Wiley & Sons, Inc.
Three‐Dimensional Inkjet‐Printed Interconnects using Functional Metallic Nanoparticle Inks
Authors: Sadie Jacob A. , Subramanian Vivek
Published: September 2014

Inkjet‐printed gold nanoparticle pillars are investigated as a high‐performance alternative to conventional flip‐chip interconnects for electronic packages, with significant advantages in terms of mechanical/chemical robustness and conductivity. The process parameters critical to pillar fabrication are described and highly uniform pillar arrays are demonstrated. More generally, this work underscores the impact of sintering on the electrical, mechanical, structural, and compositional properties of three‐dimensional nanoparticle‐based structures. Using heat treatments as low as 200 °C, electrical and mechanical performance that outcompetes conventional lead‐tin eutectic solder materials is achieved. With sintering conditions reaching 300 °C it is possible to achieve pillars with properties comparable to bulk gold. This work demonstrates the immense potential for both inkjet printing and metal nanoparticles to become a viable and cost‐saving alternative to both conventional electronic packaging processes and application‐specific integration schemes.
Polyoxometalate‐coupled Graphene via Polymeric Ionic Liquid Linker for Supercapacitors
Authors: Yang MinHo , Choi Bong Gill , Jung Sung Chul , Han Young‐Kyu , Huh Yun Suk , Lee Sang Bok
Published: September 2014

The integration of electrical double‐layer capacitive and pseudocapacitive materials into novel hybrid materials is crucial to realize supercapacitors with high energy and power densities. Here, high levels of energy and power densities are demonstrated in supercapacitors based on a new type of nanohybrid electrode consisting of polyoxometalate (POM)‐coupled graphene in which a polymeric ionic liquid (henceforth simply PIL) serves as an interfacial linker. The adoption of PIL in the construction of nanohybrids enables a uniform distribution of discrete POM molecules along with a large surface area of graphene sheets. When testing electrochemical characteristics under a two‐electrode system, as‐prepared supercapacitors exhibit a high specific capacitance (408 F g−1 at 0.5 A g−1), rapid rate capability (92% retention at 10 A g−1), a long cycling life (98% retention during 2000 cycles), and high energy (56 Wh kg−1) and power (52 kW kg−1) densities. First‐principles calculations and impedance spectroscopy analysis reveal that the PILs enhance the redox reactions of POMs by providing efficient ion transfer channels and facilitating the charge transfer in the nanohybrids.
High‐Performance Flexible Broadband Photodetector Based on Organolead Halide Perovskite
Authors: Hu Xin , Zhang Xiaodong , Liang Lin , Bao Jian , Li Shuang , Yang Wenlong , Xie Yi
Published: September 2014

Organolead halide perovskites have attracted extensive attentions as light harvesting materials for solar cells recently, because of its high charge‐carrier mobilities, high photoconversion efficiencies, low energy cost, ease of deposition, and so on. Herein, with CH3NH3PbI3 film deposited on flexible ITO coated substrate, the first organolead halide perovskite based broadband photodetector is demonstrated. The organolead halide perovskite photodetector is sensitive to a broadband wavelength from the ultraviolet light to entire visible light, showing a photo‐responsivity of 3.49 A W−1, 0.0367 A W−1, an external quantum efficiency of 1.19×103%, 5.84% at 365 nm and 780 nm with a voltage bias of 3 V, respectively. Additionally, the as‐fabricated photodetector exhibit excellent flexibility and robustness with no obvious variation of photocurrent after bending for several times. The organolead halide perovskite photodetector with high sensitivity, high speed and broad spectrum photoresponse is promising for further practical applications. And this platform creates new opportunities for the development of low‐cost, solution‐processed and high‐efficiency photodetectors.
Bio‐Hybrid Tumor Cell‐Templated Capsules: A Generic Formulation Strategy for Tumor Associated Antigens in View of Immune Therapy
Authors: Lybaert Lien , De Vlieghere Elly , De Rycke Riet , Vanparijs Nane , De Wever Olivier , De Koker Stefaan , De Geest Bruno G.
Published: September 2014

For the development of effective anti‐cancer vaccines, tumor associated antigens need to be internalized by antigen presenting cells alongside specific co‐stimulatory signals. Interestingly, relative to soluble antigens, nano‐ and micro‐particulate antigens are much better presented to CD8 T cells, a crucial step in the induction of cytotoxic T cells that can eliminate malignant cells. In this regard, a generic strategy to encapsulate cancer cell derived proteins into a particulate delivery system would be of high interest. Here we present a versatile approach to incorporate cancer cell proteins into polymeric capsules using the cells themselves as templates for layer‐by‐layer assembly of complimentary interacting species. After coating, the cells are killed by hypo‐osmotic treatment leading to bio‐hybrid capsules loaded with cell lysate. Particular focus is devoted in this work on choosing the optimal coating components and conditions to maximize cell membrane integrity during the coating process, minimize pre‐mature protein release and achieve optimal encapsulation of cell lysate upon lysis of the cells. To further underline the generic nature of our approach, we demonstrate that heat shock proteins, important immune‐activators, can be induced and encapsulated into the bio‐hybrid capsules.
Evaluating Thiourea Architecture for Intramolecular [2+2] Photocycloaddition of 4‐Alkenylcoumarins
Authors: Vallavoju Nandini , Selvakumar Sermadurai , Jockusch Steffen , Prabhakaran Manoj Thathamkulam , Sibi Mukund P. , Sivaguru Jayaraman
Published: September 2014

The efficiency of [2+2] photocycloadditions of 4‐alkenylcoumarins was evaluated with various thiourea skeletons to develop thiourea‐based catalysts for promoting photochemical reactions. Our results indicate that the excited state chemistry is dependent on the nature of the thiourea catalyst employed to activate the photoactive substrate.

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