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In der vorliegenden Studie untersuchten wir eine Auswilderung
von in einer Voliere gehaltenen Dohlen (Corvus monedula),
die in einer erfolgreichen Etablierung einer Wildkolonie
mündete. Die Auswilderung erfolgte in zwei Stufen in
den Jahren 2007 und 2009. Im ersten Projektjahr lag der
Fokus unserer Untersuchung auf der räumlichen Ausbreitung
der ausgewilderten Individuen, die zunächst nur allmählich,
dann jedoch fast sprunghaft erfolgte. Mit der
räumlichen Ausbreitung der Individuen auf andere als die
in unmittelbarer Nähe zur Voliere gelegenen Bereiche war
auch eine veränderte funktionelle Nutzung des Raumes
verbunden, in der vor allem das Zentrum der Aktivitäten
der Vögel verlagert wurde. Das zweite Projektjahr war der
Untersuchung gewidmet, wie sich eine neuerlich ausgewilderte
Dohlengruppe mit der bereits bestehenden Wildkolonie
zu einer sozialen Gruppe zusammenschließen würde. In
diesem Prozess benutzten die beiden Kolonien unterschiedliche
Strategien der Annäherung. Während Individuen der
Wildkolonie mit den hinzugekommenen Individuen häufiger
in aggressiver Weise Kontakt aufnahmen, zeigten umgekehrt
die neu ausgewilderten Individuen gegenüber Individuen
der Wildkolonie vor allem soziopositives Verhalten.
Obwohl die beiden Kolonien nach nur rund zwei Wochen
räumlich als eine Kolonie betrachtet werden durften, zeigen
unsere Ergebnisse, dass der soziale Zusammenschluss erst
nach etwa zwei Monaten erreicht war. Unsere Studie zeigt
auch Kontextfaktoren bzw. Faktoren der Biologie von Dohlen
auf, die für eine erfolgreiche Auswilderung von besonderer
Bedeutung sind: das visuelle Kennenlernen der neuen
Umgebung, die Dynamik von Dohlenkolonien als offene
Gruppen, in denen Abwanderungen und Neuzugänge ein
häufiges Phänomen sind und für Auswilderungszwecke
genutzt werden können und die Wichtigkeit einer etablierten
Dominanzhierarchie in der dominante Individuen Führungsrollen
übernehmen und Artgenossen diesen folgen
können.
Die Zippammer kommt in Mitteleuropa an ihrer nördlichsten
Verbreitungsgrenze in den klimatisch günstigen Gegenden
des Mittelrheins mit seinen Nebenflüssen und des Mains
vor. Diese sind gekennzeichnet durch felsige, nach S ausgerichtete
sonnenscheinreiche Gebiete und Terrassenweinbau
wie an Ahr, Mosel, Mittelrhein, Nahe und Main gegeben.
Dagegen ist die Art im Südschwarzwald und den Vogesen
überwiegend in Höhen von über 1.000 m, in der Schweiz
sogar über 2.300 m, verbreitet. Das dortige Habitat ist ebenfalls
von steiler, felsiger Struktur oder befindet sich auf
Kahlschlägen oder Windbruchflächen. Nach der Revierbesetzung
im März-April ist es dort häufig bis in den Juni hinein
kalt, stürmisch, wolkenverhangen und nass bis über die
erste Brutperiode hinaus. Die südliche Exposition und spezielle
Beschaffenheit aller Reviere, auch in großen Höhen,
kann in Zusammenhang gebracht werden mit der bevorzugten
Insektenentwicklung auf solchen Hängen, zum einen der
Lepidopteren-Larven für die Aufzucht der ersten Zippammer-
Brut und dann folgend der Heuschrecken als Nahrungsgrundlage
für die Aufzucht der zweiten Brut. Am klimatisch
günstigen Südschwarzwald-Hangfuß, wie auch am klimatisch
bevorzugten Hangfuß der Vogesen, den Weinbau-
Terrassen des Elsass, kommt die Zippammer nicht vor.
Aufgrund der zeitweisen Besiedlung von Fichtenkahlschlägen
am Ostabfall des Pfälzerwaldes und nicht der Weinberg-
Terrassen des klimatisch günstigen Hangfußes des Pfälzerwaldes
(Pfälzer Weinstrasse) wird geschlossen, dass die
Besiedlung des Pfälzerwaldes von dem gebirgsadaptierten
Zippammervorkommen der südlich gelegenen Vogesen
erfolgte (Entfernung 150 km) und nicht von dem wärmeadaptierten
nördlich liegenden mittelrheinischen Zippammervorkommen.
Es wird die Hypothese aufgestellt, dass die
nördlichen weinbergadaptierten Vorkommen zusammen
und die südlich gelegenen gebirgeadaptierten Vorkommen
der Zippammer je eine genetisch getrennte Metapopulation
bilden könnten und ihr unterschiedliches Verhalten nicht
nur ihre phänotypische Plastizität widerspiegelt.
We extend the recently developed strong coupling, dimensionally reduced Polyakov-loop effective theory from finite-temperature pure Yang-Mills to include heavy fermions and nonzero chemical
potential by means of a hopping parameter expansion. Numerical simulation is employed to investigate the weakening of the deconfinement transition as a function of the quark mass. The
tractability of the sign problem in this model is exploited to locate the critical surface in the (M/T,m/T,T) space over the whole range of chemical potentials from zero up to infinity.
LatticeQCD using OpenCL
(2011)
We analyze the universal critical behavior at the chiral critical point in QCD with three degenerate quark masses. We confirm that this critical point lies in the universality class of the three dimensional Ising model. The symmetry of the Ising model, which is Z(2), is not directly realized in the QCD Hamiltonian. After making an ansatz for the magnetization- and energy-like operators as linear admixtures of the chiral condensate and the gluonic action, we determine several non-universal mixing and normalization constants. These parameters determine an unambiguous mapping of the critical behavior in QCD to that of the 3d-Ising model. We verify its validity by showing that the thus obtained orderparameter scales in accordance with the magnetic equation of state of the 3d-Ising model.
Introduction: The triggering receptor expressed on myeloid cells-1 (TREM-1) is known to be expressed during bacterial infections. We investigated whether TREM-1 is also expressed in non-infectious inflammation following traumatic lung contusion.
Methods: In a study population of 45 adult patients with multiple trauma and lung contusion, we obtained bronchoalveolar lavage (BAL) (blind suctioning of 20 ml NaCl (0.9%) via jet catheter) and collected blood samples at two time points (16 hours and 40 hours) after trauma. Post hoc patients were assigned to one of four groups radiologically classified according to the severity of lung contusion based on the initial chest tomography. Concentration of soluble TREM-1 (sTREM-1) and bacterial growth were determined in the BAL. sTREM-1, IL-6, IL-10, lipopolysaccharide binding protein, procalcitonin, C-reactive protein and leukocyte count were assessed in blood samples. Pulmonary function was evaluated by the paO2/FiO2 ratio.
Results: Three patients were excluded due to positive bacterial growth in the initial BAL. In 42 patients the severity of lung contusion correlated with the levels of sTREM-1 16 hours and 40 hours after trauma. sTREM-1 levels were significantly (P < 0.01) elevated in patients with severe contusion (2,184 pg/ml (620 to 4,000 pg/ml)) in comparison with patients with mild (339 pg/ml (135 to 731 pg/ml)) or no (217 pg/ml (97 to 701 pg/ml)) contusion 40 hours following trauma. At both time points the paO2/FiO2 ratio correlated negatively with sTREM-1 levels (Spearman correlation coefficient = -0.446, P < 0.01).
Conclusions: sTREM-1 levels are elevated in the BAL of patients following pulmonary contusion. Furthermore, the levels of sTREM-1 in the BAL correlate well with both the severity of radiological pulmonary tissue damage and functional impairment of gas exchange (paO2/FiO2 ratio).
Since combinatorial chemistry and high throughput screening have become a common technique in the drug discovery phase the number of compounds being considered has increased frequently. These structures are often characterized by high molecular weight, high lipophilicity and low solubility in aqueous and physiological media. Due to the generally poor bioavailability, new in vitro techniques were needed for screening of pharmacokinetic properties. An important parameter for these screening methods is the implementation at an early state of drug discovery phase, to find potential lead structures, before investment costs become significant. The established in vitro methods for the prediction of membrane interaction are not reliable especially for poorly soluble compounds. A new method that is fast and easy to use, requires only small amounts of NCE and which can provide more reliable predictions is needed. In this study, a new screening technique based on surface activity profiling for the prediction of oral drug absorption was evaluated with special emphasis on the predictability of biological membrane interaction of poorly soluble drug compounds. It was demonstrated that drug absorption through a bilayer membrane can be modeled by the orientation of compounds at the air/water interface. Thus amphilicity of a drug is generally related to both oral absorption and blood brain barrier penetration. In turn, amphiphilicity is influenced by the lipophilicity, size and charge distribution of a drug. Surface activity profiling was determined by analysis of surface pressure profiles using the Gibbs adsorption isotherm. The surface activity measurements were carried out using a multichannel tensiometer Delta 8, which was developed by Kibron to be utilized in conjugation high throughput screening in early drug discovery processes. For this study two test sets were analyzed, one for the prediction of gastrointestinal wall interaction and the second for the prediction of the penetration behavior at the blood brain barrier. Both test sets consist of drug compounds with a wide range of absorption properties and consist mainly of compounds with poor water solubility. Since the drugs characteristics varied, they were classified according to water solubility and surface activity and a sample preparation method for each group was established. For the prediction of oral drug absorption, three different methods were established to model the interaction of compound and gastrointestinal wall. For drug compounds with solubility above 1mmol/L the traditional shake-flask method enabled the determination of the amphiphilic properties of drug compounds in pure aqueous media. Compounds with solubility below 1mmol/L tend to not to exhibit any increase in surface activity. Thus surface tension measurements of compounds, which exhibited a limited surface activity due to poor aqueous solubility, were conducted from stock solutions prepared with various organic solvents. Mainly polar organic solvents were used. A mixture of DMSO and DMF resulted in the best combination of properties: the intensive solubility enhancing effect of DMF and the lower intrinsic surface activity of DMSO. The polar solvent ruptured the water clusters, so that highly lipophilic structures had a higher affinity to the solvent and higher concentrations could be obtained. For these compounds higher maximum surface pressure were generated than was possible in pure aqueous media. The surface pressure data were correlated with the fraction absorbed values in vivo. However it was found that poor water solubility is not the only limiting step to exhibiting any surface activity. Some compounds were showed no surface activity in either solvent system. Therefore a micelle vehicle method was established using short chain phospholipids to mimic the gastrointestinal wall. It could be concluded from the results, that non surface active drugs can interact with the phospholipids micelle vehicle in a way analogous to their interaction with the membrane bilayer. The relative critical micelle concentration was correlated with the fraction absorbed of this test set. A sample preparation schema based on the three types of drugs was established. This schema enabled us to predict the absorbance of slightly soluble and poorly soluble drugs with acceptable reliability for early compound screening. For the prediction of blood brain barrier penetration using surface activity profiling as analyzing method, a test set with very poorly soluble characteristics was chosen. The sample preparation method was based on a strictly aqueous approach using the ‘shake flask’ method. The surface tension measurements enabled correlation of the amphiphilic properties of the very poorly soluble drug compounds with BBB uptake. From the aqueous surface pressure profiles and the determination of physicochemical parameters, it was found that blood brain barrier is more likely when a drug provides a small cross-sectional area, As, at the interface. The cross-sectional area is the only parameter which is independent from the maximal concentration in aqueous media and it is particularly suitable for lower solubility compounds. In summary, it was shown that amphilicity is related to biological membrane interaction in the human body and that surface activity profiling with appropriate sample preparation can be used as a reliable screening tool for the prediction of oral drug absorption of poorly soluble drugs. Furthermore an in vitro screening method of blood-brain-barrier penetration was established.