Flavour and Spin of the Proton and the Meson Cloud

We present a complete set of formulas for longitudinal momentum distribution functions (splitting functions) of mesons in the nucleon. It can be applied in the framework of convolution formalism to the deep-inelastic structure functions (quark distributions) of the nucleon viewed as a system composed of virtual 'mesons' and 'baryons'. Pseudoscalar and vector mesons as well as octet and decuplet baryons are included. In contrast to many approaches in the literature the present approach ensures charge and momentum conservation by the construction. We present not only spin averaged splitting functions but also helicity dependent ones, which can be used to study the spin content of the nucleon. The cut-off parameters of the underlying form factors for different vertices are determined from high-energy particle production data. This information allows one to calculate the flavour and spin content of the nucleon. The value of the Gottfried Sum Rule obtained from our model (S_G = 0.224) nicely agrees with that obtained by the NMC. In addition, we calculate the x-dependence of the \bar d - \bar u asymmetry and get an impressive agreement with a recent fit of Martin-Stirling-Roberts. The calculated axial coupling constants for semileptonic decays of the octet baryons agree with the experimental data already with SU(6) wave function for the bare nucleon. Although we get improvements for the Ellis-Jaffe Sum Rules for the proton and neutron in comparison to the naive quark model, the MCM is not sufficient to reproduce the experimental data.Comment: written in ReVTex, 53 pages, 11 PS-figure

Iron Behaving Badly: Inappropriate Iron Chelation as a Major Contributor to the Aetiology of Vascular and Other Progressive Inflammatory and Degenerative Diseases

The production of peroxide and superoxide is an inevitable consequence of aerobic metabolism, and while these particular "reactive oxygen species" (ROSs) can exhibit a number of biological effects, they are not of themselves excessively reactive and thus they are not especially damaging at physiological concentrations. However, their reactions with poorly liganded iron species can lead to the catalytic production of the very reactive and dangerous hydroxyl radical, which is exceptionally damaging, and a major cause of chronic inflammation. We review the considerable and wide-ranging evidence for the involvement of this combination of (su)peroxide and poorly liganded iron in a large number of physiological and indeed pathological processes and inflammatory disorders, especially those involving the progressive degradation of cellular and organismal performance. These diseases share a great many similarities and thus might be considered to have a common cause (i.e. iron-catalysed free radical and especially hydroxyl radical generation). The studies reviewed include those focused on a series of cardiovascular, metabolic and neurological diseases, where iron can be found at the sites of plaques and lesions, as well as studies showing the significance of iron to aging and longevity. The effective chelation of iron by natural or synthetic ligands is thus of major physiological (and potentially therapeutic) importance. As systems properties, we need to recognise that physiological observables have multiple molecular causes, and studying them in isolation leads to inconsistent patterns of apparent causality when it is the simultaneous combination of multiple factors that is responsible. This explains, for instance, the decidedly mixed effects of antioxidants that have been observed, etc...Comment: 159 pages, including 9 Figs and 2184 reference

Nach dem Dankfeste, wegen des von Seiner Königl. Majestät von Grosbritannien, Georg dem Dritten, wieder hergestellten Friedens, suchte einer verehrungswürdigen Versammlung in dem Hörsaale der Zellischen Stadtschule die Größe dieser Wohlthat nebst den überstandenen Gefahren des Krieges durch nachstehende Rede zu schildern der Rector Joh. Heinr. Steffens : den 25ten Januar. 1763.

Fingerprint nach Ex. der NLB Hannover und der ULB Sachsen-AnhaltVorlageform des Erscheinungsvermerks: Zelle, gedruckt und verlegt von Johann Dietrich Schulze, Königl. Hofbuchdrucker

Geschlechts-Geschichte des hochadelichen Hauses von Campe auf Isenbüttel und Wettmarshagen : nebst dazu-gehörigen Stammtaf., Wapen, Siegeln und andern grösten-theils noch ungedr. Urkunden und Nachrichten

zusammengetr. von J. H. Steffen

Placidus oder Eustach : ein Trauerspiel in fünf Aufzügen verfertiget und durch einige seiner Untergebenen öffentlich aufgeführet

von Johann Heinrich Steffens, des Zellischen Lycei Con-Rector und der Königl. deutschen Gesellschaft zu Göttingen MitgliedeVorlageform der Veröffentlichungsangabe: "Zelle, Verlegts Joachim Andreas Deetz, 1749."Fraktu

Praxistransfer Schul- und Unterrichtsforschung. Eine Problemskizze (Teil I)

Steffens U, Heinrich M, Dobbelstein P. Praxistransfer Schul- und Unterrichtsforschung. Eine Problemskizze (Teil I). Schulverwaltung NRW. 2020;(5):145-147

Das Netzwerk „Empiriegestützte Schulentwicklung“ (EMSE) als Forum des Wissenstransfers für die Landesinstitute und Qualitätseinrichtungen der Länder

Steffens U, Heinrich M, Dobbelstein P. Das Netzwerk „Empiriegestützte Schulentwicklung“ (EMSE) als Forum des Wissenstransfers für die Landesinstitute und Qualitätseinrichtungen der Länder. Berufsbildung - Zeitschrift für Theorie-Praxis-Dialog. 2021;75 (188):11-13