192 research outputs found
33 years after the last felling: On the development of stand structure in the strict forest reserve "Grosser Freeden" (Teutoburg Forest, Germany)
No full textTitle of the paper: 33 years after the last felling: On the development of stand structure in the strict forest reserve "Grosser Freeden" (Teutoburg Forest, Germany). The forest district "Grosser Freeden" is situated in the northwestern Teutoburg Forest (Lower Saxony, northwest Germany) and became a strict forest reserve in 1972. We investigate how the deciduous forest stands in this reserve evolved after the cessation of timber harvesting and which biotic and abiotic factors led to the current status. In this context, forest history is considered as well. In former times, the investigation area was owned by the prince-bishopric of Osnabruck. Following owners were the Kingdom of Hanover, Prussia and since 1945 the federal state of Lower Saxony. Nowadays, one-storied Fagus sylvatica L. stands are growing on the southern slope that is covered with thick, loess-derived soils. The steep northern slope is dominated by two-storied Fagus sylvatica stands with several secondary tree species, the Rendzina soil is quite shallow (Tab. 1). Even 33 years after the last harvesting operations, it is still apparent how the stands had once been managed. However, tree species that are not site-adapted or less competitive (e.g. Picea abies (L.) Karst. or Ulmus glabra Huds.) are increasingly being replaced by the competitive Fagus sylvatica. Hence, during the observation period (1971-2004), tree-layer diversity decreased, while tree-layer Volume increased (Tab. 2, 4, 5, Fig. 2, 3). Besides high tree mortality due to competition, a considerable dieback of Ulmus glabra occurred, which can be explained by the Dutch elm disease temporary drought stress. Regarding Acer pseudoplatanus L., the analysis of a real time series reveals that this tree species grows faster than Fagus sylvatica in early stages (Fig. 4). The difference of rate of growth between these two tree species decreases with increasing age, until finally Fagus sylvatica overgrows Acer pseudoplatanus. In contrast, Fraxinus excelsior L. grows better than Fagus sylvatica. This trend increases during the last two decades of the observation period and can be explained by a combination of site factors and stand history (Tab. 3). The volume of decaying wood amounts in average to 34 m(3) per hectare (Tab. 6). Due to the protection of natural processes the abundance of decaying wood will increase in the future. Especially in homogeneous and one-storied Fagus sylvatica stands a considerable number of trees will die back in the next decades. In 2004, we found almost no tree regeneration due to Fagus sylvatica competition and very high Population density of fallow deer (Dama dama L.). Since 2005, fallow deer numbers have been reduced by intensified hunting. As a consequence, the forest can develop in a more natural way henceforth. For future stand structure and tree species composition, especially disturbances such as wind throw will be crucial
33 years after the last felling: On the development of stand structure in the strict forest reserve "Grosser Freeden" (Teutoburg Forest, Germany)
No full textTitle of the paper: 33 years after the last felling: On the development of stand structure in the strict forest reserve "Grosser Freeden" (Teutoburg Forest, Germany). The forest district "Grosser Freeden" is situated in the northwestern Teutoburg Forest (Lower Saxony, northwest Germany) and became a strict forest reserve in 1972. We investigate how the deciduous forest stands in this reserve evolved after the cessation of timber harvesting and which biotic and abiotic factors led to the current status. In this context, forest history is considered as well. In former times, the investigation area was owned by the prince-bishopric of Osnabruck. Following owners were the Kingdom of Hanover, Prussia and since 1945 the federal state of Lower Saxony. Nowadays, one-storied Fagus sylvatica L. stands are growing on the southern slope that is covered with thick, loess-derived soils. The steep northern slope is dominated by two-storied Fagus sylvatica stands with several secondary tree species, the Rendzina soil is quite shallow (Tab. 1). Even 33 years after the last harvesting operations, it is still apparent how the stands had once been managed. However, tree species that are not site-adapted or less competitive (e.g. Picea abies (L.) Karst. or Ulmus glabra Huds.) are increasingly being replaced by the competitive Fagus sylvatica. Hence, during the observation period (1971-2004), tree-layer diversity decreased, while tree-layer Volume increased (Tab. 2, 4, 5, Fig. 2, 3). Besides high tree mortality due to competition, a considerable dieback of Ulmus glabra occurred, which can be explained by the Dutch elm disease temporary drought stress. Regarding Acer pseudoplatanus L., the analysis of a real time series reveals that this tree species grows faster than Fagus sylvatica in early stages (Fig. 4). The difference of rate of growth between these two tree species decreases with increasing age, until finally Fagus sylvatica overgrows Acer pseudoplatanus. In contrast, Fraxinus excelsior L. grows better than Fagus sylvatica. This trend increases during the last two decades of the observation period and can be explained by a combination of site factors and stand history (Tab. 3). The volume of decaying wood amounts in average to 34 m(3) per hectare (Tab. 6). Due to the protection of natural processes the abundance of decaying wood will increase in the future. Especially in homogeneous and one-storied Fagus sylvatica stands a considerable number of trees will die back in the next decades. In 2004, we found almost no tree regeneration due to Fagus sylvatica competition and very high Population density of fallow deer (Dama dama L.). Since 2005, fallow deer numbers have been reduced by intensified hunting. As a consequence, the forest can develop in a more natural way henceforth. For future stand structure and tree species composition, especially disturbances such as wind throw will be crucial
A novel BCR-JAK2 fusion gene is the result of a translocation (9;22)(p24;q11) in a case of CML.
No full textTranslocation of C-13-labeled leaf or root litter carbon of beech (Fagus sylvatica L.) and ash (Fraxinus excelsior L.) during decomposition - A laboratory incubation experiment
No full textThe aim was to quantify medium term litter type and litter mixture effects on the translocation and transformation dynamics of root and leaf litter C during decomposition. Partitioning of C-13-labeled root or leaf litter C (beech - Fagus sylvatica L., ash - Fraxinus excelsior L.) to CO2, water-extractable organic C (WEOC), microbial biomass C (C-MB) and light (LF) and heavy soil fraction (HF) was determined in a laboratory decomposition experiment of 206 days. The proportions of C mineralized from ash leaf (34%) and root litter (29%) were higher than those from beech leaf (24%) and root litter (23%). In mixture with beech, the mineralization of ash leaf litter was enhanced. Mineralization was positively correlated with litter-derived WEOC until day 29. Water-extractable organic C declined with time, until <0.1% of litter C remained in this fraction. Litter-C recovery in C-MB was higher for ash (0.7-1.0%) than for beech (0.2-0.4%). The litter C recovery in HF (4-12%) was positively correlated with that in WEOC (days 9 and 29) and C-MB, but did not differ between treatments. Ash leaf litter mineralization showed different behavior in mixed treatments from pure treatments. Thus, the ability to transfer results from pure to mixed treatments is limited. The litter differed in chemical composition and in mineralization dynamics, but differences in partitioning to HF, WEOC and MB were finally of minor importance. (C) 2015 Elsevier Ltd. All rights reserved
SEQUENTIAL FISH-ANALYSES OF CIRCULATING CD34+-CELLS IN MDS - A SUITABLE METHOD FOR CYTOGENETIC MONITORING UNDER S-AZACYTIDINE OR LENALIDOMIDE
No full textThe new old era : a diagnosis of time and the present 1817 - 1821 in the works of Henrik Steffens
No full textHenrik (Hendrik, Henrich) Steffens, Naturwissenschaftler, Philosoph, Verfasser politischer Schriften und umfangreicher Novellen, wurde 1773 in Stavanger geboren. Seine Mutter war Dänin, sein Vater Deutscher. Steffens lehrte an den Universitäten Kiel, Kopenhagen, Halle, Breslau und Berlin, war mehrmals Rektor und gehörte zu den Universitätsreformern um Wilhelm von Humboldt. Schelling, Tieck und Schleiermacher waren die bekanntesten unter seinen vielen Freunden. Die rund 3000 Seiten umfassende Autobiographie, die Steffens in seinen letzten Lebensjahren schrieb, ist eine wichtige, auch heute noch lesenswerte, wenn auch hier und da durch großen zeitlichen Abstand zwischen Ereignis und Niederschrift etwas getrübte Quelle für die Zeit zwischen Französischer Revolution und 1840. Steffens starb 1845 in Berlin. Eine der Gedenkreden hielt Schelling.
Thema der vorliegenden, 1961 abgeschlossenen Dissertation ist Steffens als Diagnostiker seiner Zeit - Zeit verstanden als Epoche - und seiner unmittelbaren Gegenwart. Für ihn bedeutete dies, ausgehend von der Vorstellung, Geschichte sei ein in seinen Grundzügen festliegender, sich kontinuierlich offenbarender Prozess, den gegenwärtigen Stand und die Richtung dieses Prozesses sowie die Charakteristika des jeweils Erreichten zu bestimmen. Für Steffens war die Geschichte Deutschlands im Mittelalter und der Neuzeit vor allem durch drei große Gegensätze bestimmt: durch die kriegerischen Auseinandersetzungen zwischen Ost und West, durch das Ringen von Kaiser und Papst um die Vorherrschaft und durch die Feindschaft von Deutschen und Franzosen, die weit mehr sei als nur die gegenseitige Abneigung zweier Völker, nämlich Konfrontation zweier grundverschiedener, unvereinbarer Geisteshaltungen - eine Konfrontation, die auch mit den militärischen Siegen über Frankreich keineswegs ausgestanden war.
Im Zentrum der Dissertation steht das erste große zeitdiagnostische Werk Steffens': "Die gegenwärtige Zeit und wie sie geworden, mit besonderer Rücksicht auf Deutschland". Es erschien 1817. Der Zeitpunkt war günstig: Für wenige Jahre nach dem Wiener Kongress war der Griff der Zensoren gelockert, konnten auch Gedanken und Thesen publiziert werden, die nicht mit der Meinung der Herrschenden übereinstimmten. Bei den "Caricaturen des Heiligsten", die 1819 und 1821 in zwei Bänden erschienen, hatten sich die Voraussetzungen für eine derartige Publikation schon wieder geändert: die Karlsbader Beschlüsse griffen. Aber auch die politischen Ansichten des Autors waren nicht mehr die gleichen.
Um 1815 war Steffens fest überzeugt, mit dem Sieg in den Befreiungskriegen habe ein neues Zeitalter begonnen. Deutschland sei "wiedergeboren" worden und gebe nun Anlass zu den schönsten Hoffnungen. Nach dem vorangegangenen geistigen Aufbruch - für Steffens vor allem repräsentiert durch die Romantik und die Schellingsche Naturphilosophie - stehe nun auch auf politischem Gebiet ein epochaler Einschnitt unmittelbar bevor. Nach 1817 begann er, Diagnose und Prognose in Frage zu stellen. Er zweifelte zunehmend daran, dass wirklich eine neue Epoche begonnen habe für das politische Deutschland und sah in der Gegenwart mehr und mehr nur ein Vorspiel zu einer bedeutenden, sich aber erst ankündigenden Zukunft. Und 1822, in seiner "Anthropologie", sprach Steffens überhaupt nicht mehr von einer politischen Wende. Hier äußerte er nur noch vage Hoffnungen auf eine bedeutende Zukunft in den Natur- und Geisteswissenschaften wie auf religiösem Gebiet.
Parallel zu dieser Erosion der Gewissheiten, Überzeugungen und Hoffnungen in wenigen Jahren vollzog sich bei Steffens ein Wandel von überwiegend liberalen zu konservativen Ansichten. Am deutlichsten wird dies beim Vergleich der Spielräume, die er für individuelles Handeln sieht. 1817 noch gesteht er dem Einzelnen durchaus Möglichkeiten zu, innerhalb gewisser Grenzen und unter bestimmten Bedingungen Richtung und Tempo der geschichtlichen Entwicklung zu beeinflussen. Von 1819 an aber dominieren Prädetermination und Eigengesetzlichkeit der Zeit so sehr, dass individuelles Handeln kaum noch Chancen hat, auf den Lauf der Dinge einzuwirken. Auch an anderen Stellen sind erhebliche Akzentverschiebungen zu beobachten: Nicht mehr die Freiheit als Wert an sich ist anzustreben, sondern ein ausbalanciertes Verhältnis, ja die "Identität" von Freiheit und Notwendigkeit, und die Forderung nach allgemeiner Gleichheit ist ersetzt durch das Plädoyer für eine "organische" Gliederung des Volkes, in der die Einzelnen je nach ihren Gaben und den ihnen gestellten Aufgaben ihren Platz einzunehmen haben.
Henrik (Hendrik, Henrich) Steffens, natural scientist, philosopher, author of political writings and short novels, was born in 1773 at Stavanger, Norway. His mother was Danish, his father German. Steffens lectured at the Universities of Kiel, Copenhagen, Halle, Breslau and Berlin. He was a rector several times and joined the circle of university reformers headed by Wilhelm von Humboldt. Schelling, Tieck and Schleiermacher are the best known among his many friends. His extensive 3000- page autobiography written near the end of his life is an important testimony of the time between the French Revolution and 1840 and is still worthwhile reading, despite some errors caused by time intervals between the events and writings on them. Steffens died 1845 in Berlin. One of the commemorative adresses was held by Schelling.
The topic of this dissertation, which was completed in 1961, is Steffens as a diagnostician of his time - time understood as an epoch and its immediate presence. He was led by the idea that history was a process whose main structures are predetermined and continuously reveal themselves. For him the diagnosis of time therefore meant to discover the current stage of the historical process and the direction of its movement as well as the characteristics of what was already achieved. Steffens was convinced that Germany's past in medieval and modern times was primarily dominated by three fundamental contradictions: by the wars between East and West, by the struggle for hegemony between the Emperor and Pope, and by the antagonism between the Germans and French. According to Steffens, the latter was much more than a mutual antipathy between two peoples. In his view it was the confrontation between two fundamentally incompatible mentalities - a confrontation, which by no means was obsolete after the victories against France.
The dissertation mainly focuses on the first work by Steffens dealing with the diagnosis of time: "Die gegenwärtige Zeit und wie sie geworden, mit besonderer Rücksicht auf Deutschland" (The present time and how it emerged, with particular regard to Germany). The book was published at a favorable time in 1817. For a short time after the Congress of Vienna the power of censorship was reduced and it was possible to publish thoughts and ideas, which were not congruent with the opinions of the rulers. In 1819 and 1821, when the two volumes of the "Caricaturen des Heiligsten" (Caricaturies of the Holiest) were published, the condotions for such a publication had once again changed. The Resolutions of Carlsbad were taking effect, but the polotical views of the author had changed, too.
Around 1815 Steffens was deeply convinced that a new epoch had begun with the victories in the Wars of Liberation (Befreiungskriege). He believed that Germany was "born again" and that there were strong reasons for hope. Steffens expected a fundamental political shift in Germany to soon follow the spiritual awakening, which in his view was represented first of all by the (German) Romanticism and Schelling's philosophy of nature. After 1817 Steffens began to question the diagnosis and prognosis. He increasingly doubted whether a new epoch for political Germany had really begun and he increasingly recognized the present only as a prelude to a significant future, which had yet to come. In 1822, Steffens did not even mention a political shift in his "Anthropology". In that publication he only expressed vague hopes of an important future in natural sciences and arts as well as in religion.
Corresponding with the erosion of certainties, convictions and hopes, Steffens' views changed from primarily liberal to conservative in just a few years. This is most evident when comparing the scopes for individual action which he identified. In 1817 he granted individuals the possibility to influence the direction and speed of historical developments within certain limits and under certain circumstances. After 1819 however, predetermination and the entelechy of time became dominant to such an extent that individual action has almost no chance anymore to affect thecourse of events. Sigificant shifts in focus can be observed in other places as well: freedom as a value in itself is no longer strived for, rather a balance or, more precisely, the "identity" of freedom and necessity. And the demand for the universal equality of men is replaced by the plea for an "organic" structure of the people, in which individuals must assume their roles corresponding to their abilities and the tasks given to them by the authorities.
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Adequate cytogenetic examination in myelodysplastic syndromes: analysis of 529 patients
No full textIn myelodysplastic syndromes (MDS), the karyotype is one of the most significant prognostic markers with profound impact on differential diagnosis and therapeutic decisions. In a retrospective study, we examined karyotypes of bone marrow specimens of an oligocentric cohort comprising 529 patients with MDS to address the question how many metaphases need to be analyzed to detect even small cell clones with an appropriate expenditure. We found a statistically significant difference of the frequency of normal karyotypes in the patient group with 19 or less analyzed metaphases compared to the group with 20 or more metaphases analyzed (56% versus 47%, p=0.041). Furthermore, we demonstrate that the analysis of 25 or more metaphases can further improve the sensitivity of karyotype analysis and leads to the identification of additional clinically relevant abnormal clones or subclones in a substantial proportion of patients. In summary, our data suggest the examination of at least 20 metaphases in MDS. (c) 2005 Elsevier Ltd. All rights reserved
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