Mathematical structure of the temporal gauge

The mathematical structure of the temporal gauge of QED is critically examined in both the alternative formulations characterized by either positivity or regularity of the Weyl algebra. The conflict between time translation invariance and Gauss law constraint is shown to lead to peculiar features. In the positive case only the correlations of exponentials of fields exist (non regularity), the space translations are not strongly continuous, so that their generators do not exist, a theta vacuum degeneracy occurs, associated to a spontaneous symmetry breaking. In the indefinite case the spectral condition only holds in terms of positivity of the energy, gauge invariant theta-vacua exist on the observables, with no extension to time translation invariant states on the field algebra, the vacuum is faithful on the longitudinal algebra and a KMS structure emerges. Functional integral representations are derived in both cases, with the alternative between ergodic measures on real random fields or complex Gaussian random fields.Comment: Late

Cross-talk between phosphatidic acid and ceramide during ethanol-induced apoptosis in astrocytes

BACKGROUND: Ethanol inhibits proliferation in astrocytes, an effect that was recently linked to the suppression of phosphatidic acid (PA) formation by phospholipase D (PLD). The present study investigates ethanol's effect on the induction of apoptosis in astrocytes and the formation of ceramide, an apoptotic signal. Evidence is presented that the formation of PA and ceramide may be reciprocally linked during ethanol exposure. RESULTS: In cultured rat cortical astrocytes, ethanol (0.3–1 %, v/v) induced nuclear fragmentation and DNA laddering indicative of apoptosis. Concomitantly, in cells prelabeled with [(3)H]-serine, ethanol caused a dose-dependent, biphasic increase of the [(3)H]-ceramide/ [(3)H]-sphingomyelin ratio after 1 and 18 hours of incubation. As primary alcohols such as ethanol and 1-butanol were shown to inhibit the phospholipase D (PLD)-mediated formation of PA, a mitogenic lipid messenger, we tested their effects on ceramide formation. In astrocytes prelabeled with [(3)H]-serine, ethanol and 1-butanol, in contrast to t-butanol, significantly increased the formation of [(3)H]-ceramide. Moreover, exogenous PA, added to transiently permeabilized astrocytes, suppressed ethanol-induced [(3)H]-ceramide formation. Vice versa, addition of C(2)-ceramide to astrocytes inhibited PLD activity induced by serum or phorbol ester. CONCLUSION: We propose that the formation of ceramide in ethanol-exposed astrocytes is secondary to the disruption of phospholipase D signaling. Ethanol reduces the PA:ceramide ratio in fetal astrocytes, a mechanism which likely participates in ethanol-induced glial apoptosis during brain development

The diversity of scholarship on journalism: how journalism journals reflect theories, methods, and topics of journalism research - a content analysis (2008-2009)

Over the course of time various changes in journalism created a diverse media landscape. Since generally journalism studies are closely linked to its object, this leads to the question whether the diversity of journalism is reflected by journalism studies. To answer this question, we conducted a content analysis of academic articles published in seven peer-reviewed English language journalism journals. In sum, the paper will lay open gaps and desiderata, draw conclusions and suggest possible improvements for future journalism studies in an emerging media landscape

¿Continuo ecléctico, disciplina distinta o subdominio de los estudios de comunicación?: Consideraciones teóricas y conclusiones empíricas a propósito de la disciplinariedad, multidisciplinariedad y transdisciplinariedad de los estudios de periodismo

ABSTRACT - Is journalism studies a sub-domain of communication studies, adistinct discipline, a multidisciplinary merger or a transdisciplinary endeavour? This question is discussed by analyzing the 2008 and2009 volumes of seven academic journals focusing on journalismresearch. The sample includes 349 articles published in BrazilianJournalism Research, Ecquid Novi, Journalism & CommunicationMonographs, Journalism & Mass Communication Quarterly, PacificJournalism Review, Journalism Studies, or Journalism: Theory,Practice and Criticism. Overall, the findings reveal that journalismresearch mainly applies theoretical approaches and empiricalmethods deriving from other disciplines, particularly sociology, psychology or cultural studies. In many countries, however, journalism studies has reached a comparatively high level of institutionalization indicated by the large number of specific schools, professorships, professional associations and respective academic journals. In conclusion, we argue that journalism studies is a sub-domain of communication studies, which integrates andtranscends various disciplines aiming to become one of the axialsubjects of the 21st century.RESUMO - Os estudos de jornalismo são um subdomínio dos estudos decomunicação, uma disciplina distinta, uma fusão multidisciplinar ou uma tentativa transdisciplinar? Discute-se esta questão, neste artigo, através da análise dos volumes de 2008 e 2009 de sete publicações acadêmicas que focalizam a pesquisa em jornalismo. A amostra inclui 349 artigos publicados na Brazilian Journalism Research, Ecquid Novi: African Journalism Studies, Journalism & Communication Monographs, Journalism & Mass Communication Quarterly, Pacific Journalism Review, Journalism Studies e Journalism: Theory, Practice and Criticism. De modo geral, as conclusões revelam que a pesquisa em jornalismo utiliza principalmente as abordagens teóricas e os métodos empíricos derivados de outras disciplinas, especialmente da sociologia, da psicologia e dos estudos culturais. Entretanto, em muitos países os estudos de jornalismo já alcançaram um nível comparativamente alto de institucionalização, indicado pelo grande número das escolas específicas, dos cargos de professor, das associações profissionais e das respectivas publicações acadêmicas. Concluímos por defender a tese de que os estudos de jornalismo são um subdomínio dos estudos de comunicação que integra e transcende várias disciplinas visando se tornar uma das matérias mais importantes do século XXI.RESUMEN - ¿Los estudios de periodismo son un subdominio de los estudios de comunicación, una disciplina distinta, una fusión multidisciplinaria o una tentativa transdisciplinaria? Se discute esta cuestión a través del análisis de los volúmenes de 2008 y 2009 de siete publicaciones académicas que focalizan la investigación en periodismo. La muestra incluye 349 artículos publicados en Brazilian Journalism Research, Ecquid Novi: African Journalism Studies, Journalism & Communication Monographs, Journalism & Mass Communication Quarterly, Pacific Journalism Review, Journalism Studies, y Journalism: Theory, Practice and Criticism. De manera general, las conclusiones revelan que la investigación en periodismo utiliza principalmente enfoques teóricos y métodos empíricos derivados de otras disciplinas, en especial de la sociología, la psicología y los estudios culturales. Sin embargo, en muchos países los estudios de periodismo ya han alcanzado un nivel comparativamente alto de institucionalización, indicado por el gran número de escuelas específicas, cargos de profesor, asociaciones profesionales y publicaciones académicas. Como conclusión, defendemos la tesis de que los estudios de periodismo son un subdominio de los estudios de comunicación que integra y trasciende varias disciplinas con vistas a convertirse en una de las materias más importantes del siglo XXI

Careful approach: the relations of the German Bundeswehr to the media from the end of the cold war until today

Seit den 1990er Jahren ist eine zunehmende Öffnung der Bundeswehr gegenüber den Medien zu beobachten, die sich maßgeblich auf die wachsende Beteiligung deutscher Streitkräfte an Auslandseinsätzen und damit einher gehenden neuen kommunikativen Ansprüchen zurückführen lässt. Wurde die Medienarbeit in der ersten Hälfte der Neunziger Jahre noch durchgängig reaktiv betrieben, kam es in den Folgejahren zu einer aktiveren Gestaltung der militärischen Medienbeziehungen. Wie offen oder restriktiv die Medienbeziehungen im Einzelnen gestaltet werden, hängt jedoch von einem komplexen Faktorenbündel ab. Beispielweise prägen die unterschiedlichen Systemlogiken von Militär und Medien, die komplexen Organisationsstrukturen innerhalb der Bundeswehr oder das verfügbare Personal und dessen Qualifikationen die militärischen Medienbeziehungen.Since the 1990s, the German Bundeswehr increasingly opened up to the media. This can be mainly traced back to the growing number of out of area missions in conjunction with new communication needs. In the beginning of the 1990s, military media relations were generally conducted in a reactive manner, whereas they were actively shaped in the subsequent years. How open or restrictive media relations were conducted in detail is dependent upon a complex combination of factors. As such, military media relations are shaped for example by the different systems logics of the military and the media, by the complex organizational structures of the German armed forces or by the available personnel and its qualifications

How battery calorimeters can help in advancing thermal management and safety of cells and packs

With increasing energy density the thermal management of Li-ion batteries is becoming more and more important, because the thermal runaway can cause an ignition or even explosion of the battery with simultaneous release of toxic gases. In the last five years we have established battery calorimetry as a powerful and versatile electrochemical-thermal characterization technique, which allows both advancements for the thermal management and the safety of batteries. With six adiabatic Accelerating Rate Calorimeters (ARC) of different sizes combined with cyclers the IAM-AWP now operates Europe’s largest battery calorimeter center, which enables the evaluation of thermodynamic, thermal and safety data on material, cell and pack level. Calorimetry is very important as it is fundamental to obtain quantitative data on the thermal behaviour – you need to know how many watts a cell or a pack will generate and dissipate under certain conditions. This information can then be used to define the requirements for cooling and thermal management and adapt them accordingly. It will be shown how sophisticated battery calorimetry combined with thermography for the spatial temperature variation allows finding new and quantitative correlations between different critical thermally and safety related parameters that will help to design safer systems. In addition it will be explained how calorimeters allow studying the thermal runaway propagation in order to develop and qualify suitable countermeasures, such as heat protection barriers, which is currently becoming a very hot topic. The top 3 learning \u27take aways\u27 are: • Delegates will get insights into the use of battery calorimetry to provide quantitative thermal and safety data for cell and packs. • Delegates will understand how these data help to improve the thermal management and can give guidelines for safer systems • Delegates will understand that these data combined with better BMS diagnostics provide a powerful tool for the thermal runaway prevention

Distribution of catecholamine fibers in the cochlear nucleus of horseshoe bats and mustache bats

The glyoxylic-acid-induced fluorescence technique was applied to demonstrate patterns of catecholaminergic innervation within the auditory brainstem of echolocating bats and the house mouse. In the cochlear nucleus of the rufous horseshoe bat (Rhinolophus rouxi) and the mustache bat (Pteronotus parnelli), species-specific catecholaminergic innervation patterns are found that contrast with the relatively homogeneous innervation in the rodent. In both bats the subnuclei of the cochlear nucleus receive a differentially dense supply of catecholaminergic fibers, and within the subnuclei, the catecholamine innervation densities can be correlated with the tonotopic frequency representation. The areas devoted to the high-frequency echolocation calls are less densely innervated than those regions which are responsive to lower frequencies. Apart from this common scheme, there are noteworthy distinctions between the two bats which correlate with specialized cytoarchitectural features of the cochlear nucleus. The marginal cell group, located medially to the anteroventral cochlear nucleus of Pteronotus, receives the densest supply of catecholaminergic fibers of all auditory nuclei. This plexus is formed by a morphologically distinct population of catecholaminergic fibers

How Calorimetry can help in Battery Research

With increasing energy density the safety and the thermal management of Li-ion batteries is becoming more and more important, because the thermal runaway can cause an ignition or even explosion of the battery with simultaneous release of toxic gases. In the last ten years, we have established battery calorimetry as a versatile characterization technique, which allows advancements for the thermal management and the safety of batteries. With six adiabatic Accelerating Rate Calorimeters of different sizes and two sensitive Tian-Calvet calorimeters combined with cyclers we operate Europe’s largest battery calorimeter center, which enables the evaluation of thermodynamic, thermal and safety data on material, cell and pack level under quasiadiabatic and isoperibolic environments for both normal and abuse conditions (thermal, electrical, mechanical). Calorimetry allows the collection of quantitative data required for optimum battery performance and safety. This information is applied to define the requirements for thermal management. It will be explained how calorimeters can be used for studies on heat generation and dissipation of Li-ion cells. It will be shown that by measuring the specific heat capacity and the heat transfer coefficient the measured temperature data during cycling can be converted into generated and dissipated heat data, which are needed for the adjustment of the thermal management systems. It will be presented how battery calorimeters provide thermodynamic and thermal stability data on materials level, e.g. of anodes, cathodes or electrolytes or there combinations and allow to perform safety tests on cell and pack level by applying thermal, mechanical or electrical abuse conditions. The studies on materials level are especially important for Post-Li cells, which make use of more abundant materials, such as sodium or magnesium instead of Li, nickel and cobalt, because these data help to develop safe cells from the beginning all along the value chain. For the advanced Li-ion technology, a holistic safety assessment is in the focus, because the thermal runaway can have multiple interacting causes and effects. A test in the calorimeter reveals the entire process of the thermal runaway with the different stages of exothermic reactions. As a result of the different tests quantitative and system relevant data for temperature, heat and pressure development of materials and cells are provided. In addition it will be explained how calorimeters allow studying the thermal runaway propagation in order to develop and qualify suitable countermeasures, such as heat protection barriers, which is currently becoming a very hot topic