2,834 research outputs found

    Resonant backward scattering of light by a two-side-open subwavelength metallic slit

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    The backward scattering of TM-polarized light by a two-side-open subwavelength slit in a metal film is analyzed. We show that the reflection coefficient versus wavelength possesses a Fabry-Perot-like dependence that is similar to the anomalous behavior of transmission reported in the study [Y. Takakura, Phys. Rev. Lett. \textbf{86}, 5601 (2001)]. The open slit totally reflects the light at the near-to-resonance wavelengths. In addition, we show that the interference of incident and resonantly backward-scattered light produces in the near-field diffraction zone a spatially localized wave whose intensity is 10-103^3 times greater than the incident wave, but one order of magnitude smaller than the intra-cavity intensity. The amplitude and phase of the resonant wave at the slit entrance and exit are different from that of a Fabry-Perot cavity.Comment: 5 figure

    Multilingual higher education in European regions

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    Although English is often conceived as the dominant language of international and transnational communication in higher education, it is not the only medium of communication in the academic community. National, regional and local languages remain important, in some European countries more than in others. In Janssens, Mamadouh and Marácz (2011) we have argued that too little attention is paid to languages in the realm between the local and the global domain: what we called languages of regional communication, that can be used in multilingual and in border regions. Here we focus on multilingualism in higher education in regions where global and regional languages are in contact or compete with each other for hegemony. Will the languages - in the 20th century quite often national languages - of higher education be replaced by English or will there be developing a more balanced situation where next to English also national, regional and local languages play a role in higher education. We will conclude in this paper that the rise of English in the higher education in the context of national, regional and local languages is impressive but that the non-global languages have a robust position in higher education that is rooted in history and connected to the identity of its speakers. The case studies presents evidence from regions where multilingualism does not necessary mean Englishization. Flanders with the role of French, Dutch and English, Hungary and the Carpathian Basin with Hungarian as a national and minority language, and universities on the border between Romance and Germanic languages

    Systematics of heavy-ion fusion hindrance at extreme sub-barrier energies

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    The recent discovery of hindrance in heavy-ion induced fusion reactions at extreme sub-barrier energies represents a challenge for theoretical models. Previously, it has been shown that in medium-heavy systems, the onset of fusion hindrance depends strongly on the "stiffness" of the nuclei in the entrance channel. In this work, we explore its dependence on the total mass and the QQ-value of the fusing systems and find that the fusion hindrance depends in a systematic way on the entrance channel properties over a wide range of systems.Comment: Submitted to Phys. Rev. Lett., 5 pages, 3 figure

    The Last (Koy-Yukon) Interglaciation in the Northern Yukon: Evidence from Unit 4 at Ch’ijee’s Bluff, Bluefish Basin

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    The effects of predicted anthropogenic warming can be assessed in part by documenting responses to past warming events. One of the most pronounced warmings was the last interglaciation - stage 5 of the marine isotope record. A large multinational and multidisciplinary project (CELIA) was launched recently in order to gain detailed knowledge of the climate during stage 5. Several key exposures were identified by CELIA; one of them is Ch'ijee's Bluff on the Porcupine River, northern Yukon. Pollen, plant and insect macrofossils and stratigraphie evidence from Ch'ijee's Bluff show that the part of Ch'ijee's Unit 4 that is above and younger than Old Crow tephra (OCt) was deposited during an interval of climate warmer than present. When OCt was dated at 85 ka BP, the subsequent warming interval was presumed to be correlative with the early part of marine isotope stage 3. New dates on OCt show it to be 140-150 ka BP, and this means that the warm interval discussed here is more likely of stage 5 than stage 3 age. We apply the informal epithet, "Koy-Yukon interglaciation", to it and compare the Ch'ijee's Bluff Unit 4 sequence with other east Beringian sites that contain both Old Crow tephra and putative interglacial deposits.Les conséquences du réchauffement anthropique attendu pourraient en partie être évaluées à partir de nos connaissances sur les réchauffements climatiques antérieurs. Le réchauffement climatique le plus important s'est produit au cours du dernier interglaciaire (stade isotopique 5). Dans le but d'acquérir une meilleure connaissance du climat durant le stade 5, on a créé un important projet multidisciplinaire et multinational (CELIA). On a identifié plusieurs coupes clés dont celle de Ch'ijee's Bluff, de la Porcupine River, dans le nord du Yukon. Les indices fournis par le pollen, les végétaux, les macrofossiles d'insectes et la stratigraphie de Ch'ijee's Bluff démontrent que la partie de l'unité n 4 plus jeune que le tephra de Old Crow et située au-dessus a été déposée durant un intervalle plus chaud qu'aujourd'hui. Quand on a daté à 85 ka BP le tephra de Old Crow, on présumait que l'intervalle de réchauffement subséquent était corrélatif au stade isotopique 3, Les nouvelles dates le font maintenant remonter à 140-150 ka BP, ce qui signifie que le réchauffement climatique appartient plutôt au stade 5. On lui a attribué le nom informel de « interglaciaire de Koy-Yukon ». On a comparé la séquence de l'unité n 4 avec celle d'autres sites de Béringie qui renferment à la fois le tephra de Old Crow et des dépôts considérés comme étant interglaciaires.Die Auswirkungen einer erwarteten anthropogenen Erwàrmung kann man teilweise abschâtzen, indem man die Ergebnisse vergangener klimatischer Erwârmungen dokumentiert. Eine der herausragendsten klimatischen Erwârmungen war die letzte Interglazialzeit - Stadium 5 des marinen Isotop-Belegs. Kùrzlich hat man ein breitangelegtes multinationales und multidisziplinàres Projekt (CELIA) gestartet, um detaillierte Kenntnis ùber das Klima wàhrend des Stadium 5 zu erhalten. CELIA hat mehrere Schlussel-Schnitte identifiziert; einer davon ist Ch'ijee's Bluff am Porcupine River, nôrdliches Yukon. Die von Pollen, Pflanzen, Insektenmakrofossilen und Stratigraphie von Ch'ijee's Bluff gelieferten Anhaltspunkte zeigen, dass der Teil der Ch'ijee's-Einheit 4, der ùber Old Crow Tephra (OCt) liegt und jùnger ist, wâhrend eines klimatischen Intervalls. das warmer war als gengewârtig, abgelagert wurde. AIs man OCt auf 85 ka v. u. Z. datierte. nahm man an. dass das folgende Erwàrmungs-lntervall mit dem frùhen Teil des marinen Isotop-Stadiums 3 korrelierte. Neue Daten auf OCt zeigen, dass dieses 140-150 ka v. u. Z. ait ist, und das bedeutet, dass das warme Intervall, von dem hier die Rede ist. wohl eher dem Stadium 5 als dem Stadium 3 zugehôrt. Wir benutzen die informelle Bezeichnung "Koy-Yukon Interglazialzeit" und vergleichen die Ch'ijee's Bluff 4-Sequenz mit anderen Plâtzen von Ost-Bering, die sowohl Old Crow Tephra enthalten wie auch Ablagerungen, die man fur interglaziale Ablagerungen hait

    Lifetime measurements of Triaxial Strongly Deformed bands in 163^{163}Tm

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    With the Doppler Shift Attenuation Method, quadrupole transition moments, QtQ_t, were determined for the two recently proposed Triaxial Strongly Deformed (TSD) bands in 163^{163}Tm. The measured QtQ_t moments indicate that the deformation of these bands is larger than that of the yrast, signature partners. However, the measured values are smaller than those predicted by theory. This observation appears to be valid for TSD bands in several nuclei of the regionComment: 8 pages, 5 figures. Submitted to Physical Review

    Diversity in genomic organisation, developmental regulation and distribution of the murine PR72/B" subunits of protein phosphatase 2A

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    <p>Abstract</p> <p>Background</p> <p>Protein phosphatase 2A (PP2A) is a serine/threonine-specific phosphatase displaying vital functions in growth and development through its role in various signalling pathways. PP2A holoenzymes comprise a core dimer composed of a catalytic C and a structural A subunit, which can associate with a variable B-type subunit. The importance of the B-type subunits for PP2A regulation cannot be overestimated as they determine holoenzyme localisation, activity and substrate specificity. Three B-type subunit families have been identified: PR55/B, PR61/B' and PR72/B", of which the latter is currently the least characterised.</p> <p>Results</p> <p>We deduced the sequences and genomic organisation of the different murine PR72/B" isoforms: three genes encode nine isoforms, five of which are abundantly expressed and give rise to genuine PP2A subunits. Thereby, one novel subunit was identified. Using Northern blotting, we examined the tissue-specific and developmental expression of these subunits. All subunits are highly expressed in heart, suggesting an important cardiac function. Immunohistochemical analysis revealed a striated expression pattern of PR72 and PR130 in heart and skeletal muscle, but not in bladder smooth muscle. The subcellular localisation and cell cycle regulatory ability of several PR72/B" isoforms were determined, demonstrating differences as well as similarities.</p> <p>Conclusion</p> <p>In contrast to PR55/B and PR61/B', the PR72/B" family seems evolutionary more divergent, as only two of the murine genes have a human orthologue. We have integrated these results in a more consistent nomenclature of both human and murine PR72/B" genes and their transcripts/proteins. Our results provide a platform for the future generation of PR72/B" knockout mice.</p

    Enhanced transmission versus localization of a light pulse by a subwavelength metal slit: Can the pulse have both characteristics?

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    The existence of resonant enhanced transmission and collimation of light waves by subwavelength slits in metal films [for example, see T.W. Ebbesen et al., Nature (London) 391, 667 (1998) and H.J. Lezec et al., Science, 297, 820 (2002)] leads to the basic question: Can a light be enhanced and simultaneously localized in space and time by a subwavelength slit? To address this question, the spatial distribution of the energy flux of an ultrashort (femtosecond) wave-packet diffracted by a subwavelength (nanometer-size) slit was analyzed by using the conventional approach based on the Neerhoff and Mur solution of Maxwell's equations. The results show that a light can be enhanced by orders of magnitude and simultaneously localized in the near-field diffraction zone at the nm- and fs-scales. Possible applications in nanophotonics are discussed.Comment: 5 figure

    Rapport au Roi Souverain : rapport de la Commission d'Enquête ; A. M. le Secrétaire d'État de l'État Indépendant du Congo [31 octobre 1905]

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    Bakgrund: Den palliativa vården för hälso- och sjukvårdspersonal innebär att försöka uppnå den döende personens maximala livskvalitet och att lindra lidandet. Vården lutar sig mot det nationella vårdprogrammet för palliativ vård samt International Council of Nurses, ICN. Sjuksköterskans roll och uppgifter inom vården beskrivs där även de fyra hörnstenarna belyses. Syfte: Att belysa sjuksköterskornas upplevda svårigheter vid vård av patienter med palliativ diagnos. Metod: Examensarbetet är en litteraturöversikt baserad på Fribergs analysmetod. Denna litteraturöversikt inkluderar tio vetenskapliga artiklar som har sökts i databaserna CINAHL Complete och PubMed. Som en teoretisk utgångspunkt har Patricia Benners teori från novis till expert valts som en diskussion i resultatdiskussionen. Resultat: Sjuksköterskornas upplevda svårigheter av att vårda patienter med en palliativ diagnos resulterade i fyra huvudteman i litteraturöversikten; kommunikation, närstående och relation, vårdteamet samt kunskap och erfarenheter. Diskussion: Resultatet i litteraturöversikten har diskuterats utifrån Benners teori. Sjuksköterskornas upplevda svårigheter belystes genom fyra teman – kunskap och erfarenhet, närståendestöd, kommunikation mellan kollegor och gentemot patienten samt kultur som upplevd svårighet.Background: Palliative care for health professional means trying to achieve the maximum dying person's quality of life and ease suffering. The palliative care for health professionals means to try to achieve the dying person's maximum quality of life and alleviate suffering. The care inclined towards the Swedish national health care program for palliative care and the International Council of Nurses, ICN. The nurse's role and tasks in health care are described where even the four cornerstones elucidated. Aim: To elucidate the nurses perceived difficulties in nursing patients with palliative diagnosis. Method: The thesis is a literature review based on Friberg's analysis. This literature review includes ten scientific articles that have been searched in the databases CINAHL Complete and PubMed. As a theoretical base, Patricia Benner's theory from novice to expert was selected as a discussion of the results discussion. Results: The nurses perceived difficulties of caring for patients with a palliative diagnosis resulted in four main themes in the literature; communication, family and relationship, the health care team as well as knowledge and experience. Discussion: The results of the literature review are discussed based on Benner's theory. The nurses' perceived difficulties irradiated by four themes – knowledge and experience, family support, communication between colleagues and towards the patient as well the culture as perceived difficulties
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