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Wie drückend waren die Zensurverhältnisse im 18. Jahrhundert? Für das territorial zersplitterte Deutschland jener Epoche wird man eine flächendeckend zutreffende Antwort nicht geben können; überraschend aber, wie klar sich der Buchhandel zu dieser Frage geäußert hat: Friedrich Perthes zufolge herrschte damals die "vollständigste Preßfreiheit, der Sache und der That nach". Das Rätsel dieser rückhaltlos positiven Bewertung löst sich im Blick auf die durchgehend glimpfliche Behandlung, die Buchhändler in Zensurangelegenheiten erfahren haben: Ihnen kam zugute, dass der Buchhandel inzwischen zu einem bedeutenden Wirtschaftsfaktor aufgestiegen war und jede Einschränkung seiner Tätigkeit durch obrigkeitliche Kommunikationskontrolle unter Gesichtspunkten des merkantilistischen Territorialinteresses unerwünscht sein musste. Dieser Antagonismus zwischen Ökonomie und Zensur spiegelt sich auch in den kameralistisch-gewerbepolitischen Argumentationsmustern, die für die Behörden handlungsleitend geworden waren und dem Buchhandel – jedenfalls bis zur Französischen Revolution – beträchtliche Freiräume verschafft haben. Der Beitrag gibt den Blick frei auf einen Problemzusammenhang, der in der (immer noch stark vorurteilsbehafteten) Zensurgeschichtsschreibung häufig übersehen wird.
Alkylglycerol monooxygenase (AGMO) is a tetrahydrobiopterin (BH4)-dependent enzyme with major expression in the liver and white adipose tissue that cleaves alkyl ether glycerolipids. The present study describes the disclosure and biological characterization of a candidate compound (Cp6), which inhibits AGMO with an IC50 of 30–100 µM and 5–20-fold preference of AGMO relative to other BH4-dependent enzymes, i.e., phenylalanine-hydroxylase and nitric oxide synthase. The viability and metabolic activity of mouse 3T3-L1 fibroblasts, HepG2 human hepatocytes and mouse RAW264.7 macrophages were not affected up to 10-fold of the IC50. However, Cp6 reversibly inhibited the differentiation of 3T3-L1 cells towards adipocytes, in which AGMO expression was upregulated upon differentiation. Cp6 reduced the accumulation of lipid droplets in adipocytes upon differentiation and in HepG2 cells exposed to free fatty acids. Cp6 also inhibited IL-4-driven differentiation of RAW264.7 macrophages towards M2-like macrophages, which serve as adipocyte progenitors in adipose tissue. Collectively, the data suggest that pharmacologic AGMO inhibition may affect lipid storage.
Objectives: A conometric concept was recently introduced in which conical implant abutments hold the matching crown copings by friction alone, eliminating the need for cement or screws. The aim of this in vitro study was to assess the presence of microgap formation and bacterial leakage at the Acuris conometric restorative interface of three different implant abutment systems. Material and methods: A total of 75 Acuris samples of three implant-abutment systems (Ankylos, Astra Tech EV, Xive) were subjected to microbiological (n = 60) and scanning electron microscopic (SEM) investigation (n = 15). Bacterial migration into and out of the conical coupling system were analyzed in an anaerobic workstation for 48, 96, 144, and 192 h. Bacterial DNA quantification using qrt-PCR was performed at each time point. The precision of the conometric coupling and internal fit of cemented CAD/CAM crowns on corresponding Acuris TiN copings were determined by means of SEM. Results: qrt-PCR results failed to demonstrate microbial leakage from or into the Acuris system. SEM analysis revealed minute punctate microgaps at the apical aspect of the conometric junction (2.04 to 2.64 µm), while mean cement gaps of 12 to 145 µm were observed at the crown-coping interface. Conclusions: The prosthetic morse taper connection of all systems examined does not allow bacterial passage. Marginal integrity and internal luting gap between the ceramic crown and the coping remained within the clinically acceptable limits. Clinical relevance: Conometrically seated single crowns provide sufficient sealing efficiency, relocating potential misfits from the crown-abutment interface to the crown-coping interface.
Cell fate clusters in ICM organoids arise from cell fate heredity and division: a modelling approach
(2020)
During the mammalian preimplantation phase, cells undergo two subsequent cell fate decisions. During the first decision, the trophectoderm and the inner cell mass are formed. Subsequently, the inner cell mass segregates into the epiblast and the primitive endoderm. Inner cell mass organoids represent an experimental model system, mimicking the second cell fate decision. It has been shown that cells of the same fate tend to cluster stronger than expected for random cell fate decisions. Three major processes are hypothesised to contribute to the cell fate arrangements: (1) chemical signalling; (2) cell sorting; and (3) cell proliferation. In order to quantify the influence of cell proliferation on the observed cell lineage type clustering, we developed an agent-based model accounting for mechanical cell–cell interaction, i.e. adhesion and repulsion, cell division, stochastic cell fate decision and cell fate heredity. The model supports the hypothesis that initial cell fate acquisition is a stochastically driven process, taking place in the early development of inner cell mass organoids. Further, we show that the observed neighbourhood structures can emerge solely due to cell fate heredity during cell division.
Die EU verabschiedete am 21. Mai 1992 die Richtlinie zur Erhaltung der natürlichen Lebensräume sowie der wildlebenden Tiere und Pflanzen, die sogenannte Fauna-Flora-Habitat-Richtlinie (FFH-Richtlinie). Die Mitgliedsstaaten sind seitdem verpflichtet, ein europaweites Netz von besonderen Schutzgebieten zur Erhaltung der biologischen Vielfalt und zur Förderung einer nachhaltigen Entwicklung aufzubauen. In dieses Natura 2000 genannte Netz sind auch die auf der Grundlage der seit 1979 geltenden EU-Vogelschutzrichtlinie gemeldeten Europäischen Vogelschutzgebiete (EU SPA) integriert. Die reichhaltige Naturausstattung Sachsen-Anhalts ermöglichte die Auswahl von 265 FFH-Gebieten und 32 Vogelschutzgebieten (EU SPA). Die Gebiete wurden als „Gebiete von gemeinschaftlicher Bedeutung der kontinentalen und der atlantischen biogeographischen Region“ im Amtsblatt der EU vom 15.01.2008 veröffentlicht. Nach den Vorgaben der FFH- und Vogelschutzrichtlinie sind die Natura 2000-Gebiete nun als besondere Schutzgebiete national zu sichern. Darüber hinaus sind in den besonderen Schutzgebieten geeignete Maßnahmen zu treffen, um die Verschlechterung der natürlichen Lebensräume und der Habitate der Arten, für die die Gebiete ausgewiesen worden sind, zu vermeiden (vgl. Art. 6, Abs. 2 FFH Richtlinie). Alle erforderlichen Maßnahmen sind an den Ansprüchen der in den jeweiligen Gebieten vorkommenden Lebensraumtypen und Arten auszurichten.
Mit dem vorliegenden Sonderheft wird beispielhaft der Verfahrensweg der Ausweisung des Naturschutzgebietes Aland-Elbe-Niederung zur Umsetzung von Natura 2000 im Land Sachsen-Anhalt dokumentiert. Neben der Darstellung der naturräumlichen Situation des Gebietes und seiner naturschutzfachlichen Bedeutung werden insbes. Inhalt und Ablauf des Verwaltungsverfahrens sowie die Lösung der vielfältigen Nutzungskonflikte dargestellt. Dem Heft liegt eine beidseitig bedruckte Schutzgebietskarte des Landes Sachsen-Anhalt im Maßstab 1:250.000 bei. Auf einer Seite sind Schutzgebiete nach internationalem Recht dargestellt. Die zweite Seite der Karte liefert eine aktuelle Zusammenstellung (Stand 31.12.2009) der nach Landesnaturschutzrecht geschützten Gebiete und Objekte. Ein Beiheft mit Namen, Bezeichnung und Größe aller Gebiete komplettiert die Ausgabe.
The directed and elliptic flow of protons and charged pions has been observed from the semi-central collisions of a 158 GeV/nucleon Pb beam with a Pb target. The rapidity and transverse momentum dependence of the flow has been measured. The directed flow of the pions is opposite to that of the protons but both exhibit negative flow at low pt. The elliptic flow of both is fairly independent of rapidity but rises with pt. PACS numbers: 25.75.-q, 25.75.Ld
Spheroids resemble features of tissues and serve as model systems to study cell–cell and cell–ECM interactions in non-adhesive three-dimensional environments. Although it is generally accepted that mature spheroids resemble tissue properties very well, no studies relate different phases in the spheroid formation processes that contribute to tissue integrity. Tissue integrity involves the cellular processes adhesion formation, adhesion reinforcement, rearrangement as well as proliferation. They maintain the structure and function of tissues and, upon dysregulation, contribute to malignancy. We investigated spheroid formation dynamics in cell lines of different metastatic potential. We dissected spheroid formation into phases of aggregation, compaction and growth to identify the respective contributions of E-cadherin, actin, microtubules and FAK. E-cadherin, actin and microtubules drive the first two phases. Microtubules and FAK are involved in the proliferation phase. FAK activity correlates with the metastatic potential of the cells. A robust computational model based on a very large number of experiments reveals the temporal resolution of cell adhesion. Our results provide novel hypotheses to unveil the general mechanisms that contribute to tissue integrity.
The transverse mass mt distributions for deuterons and protons are measured in Pb+Pb reactions near midrapidity and in the range 0<mt–m<1.0 (1.5) GeV/c2 for minimum bias collisions at 158A GeV and for central collisions at 40 and 80 A GeV beam energies. The rapidity density dn/dy, inverse slope parameter T and mean transverse mass <mt> derived from mt distributions as well as the coalescence parameter B2 are studied as a function of the incident energy and the collision centrality. The deuteron mt spectra are significantly harder than those of protons, especially in central collisions. The coalescence factor B2 shows three systematic trends. First, it decreases strongly with increasing centrality reflecting an enlargement of the deuteron coalescence volume in central Pb+Pb collisions. Second, it increases with mt. Finally, B2 shows an increase with decreasing incident beam energy even within the SPS energy range. The results are discussed and compared to the predictions of models that include the collective expansion of the source created in Pb+Pb collisions.
Rapidity distributions for Lambda and anti-Lambda hyperons in central Pb-Pb collisions at 40, 80 and 158 AGeV and for K 0 s mesons at 158 AGeV are presented. The lambda multiplicities are studied as a function of collision energy together with AGS and RHIC measurements and compared to model predictions. A different energy dependence of the Lambda/pi and anti-Lambda/pi is observed. The anti-Lambda/Lambda ratio shows a steep increase with collision energy. Evidence for a anti-Lambda/anti-p ratio greater than 1 is found at 40 AGeV.
We present the first measurement of fluctuations from event to event in the production of strange particles in collisions of heavy nuclei. The ratio of charged kaons to charged pions is determined for individual central Pb+Pb collisions. After accounting for the fluctuations due to detector resolution and finite number statistics we derive an upper limit on genuine non-statistical fluctuations, perhaps related to a first or second order QCD phase transition. Such fluctuations are shown to be very small.