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Neu angelegte Kleingewässer werden oft durch Libellen rasch als Lebensräume in Anspruch genommen. Allerdings ist über die dauerhafte Bildung von Populationen, vor allem durch seltene und gefährdete Arten, noch wenig bekannt. Ziel dieser Studie war die Untersuchung des Besiedlungsprozesses von künstlich angelegten Gewässern durch Libellen mit besonderem Fokus auf moortypische Arten. In den Jahren 2015–2018 wurden in der Niederschlesischen Heide an sechs solchen Gewässern, drei neuen und drei alten, Exuvien von Großlibellen (Anisoptera) quantitativ aufgesammelt. Die Erfassung des Besiedlungserfolges durch Kleinlibellen (Zygoptera) erfolgte qualitativ als Zusatzinformation zur Artenvielfalt der Gewässer. Insgesamt waren 26 Libellenarten – 9 Zygoptera und 17 Anisoptera – bodenständig. Allerdings variierte der Artenreichtum deutlich sowohl zwischen den Gewässern als auch den Untersuchungsjahren, so dass sich keine klar definierten Unterschiede in der Artenvielfalt zwischen den neuen und alten Gewässern erkennen ließen. Unter der bodenständigen Arten wurden vier moortypische Großlibellen (Aeshna juncea, Leucorrhinia dubia, L. albifrons, L. pectoralis) nachgewiesen. Ununterbrochene Entwicklung ließ sich nur für A. juncea und L. dubia in einzelnen Gewässern bestätigen. Leucorrhinia albifrons kam nur sporadisch vor und wurde im letzten Untersuchungsjahr (2018) nicht mehr gefunden. Dagegen vollendete L. pectoralis ihre Entwicklung erst in den Jahren 2017–2018. Generell bevorzugten diese Arten Gewässer, in denen die Vegetation mäßig bis gut entwickelt war. Die Ergebnisse bestätigen, dass künstliche Gewässer durch ein breites Spektrum von Arten erfolgreich besiedelt werden können. Allerdings ließ sich die dauerhafte Reproduktion in den jeweiligen Gewässern nur für wenige Großlibellen nachweisen. Deshalb sind die Gewässer in der Niederschlesichen Heide nicht als langfristige Ersatzbiotope, sondern vielmehr als temporäre Fortpflanzungsbiotope von Individuen der Nebenpopulationen zu sehen.
Intestinal carriage of multidrug-resistant bacteria among healthcare professionals in Germany
(2017)
Healthcare professionals (HCP) might be at increased risk of acquisition of multidrug-resistant bacteria (MDRB), i.e., methillicin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), and multidrug-resistant gram-negative bacteria (MDRGN) and could be an unidentified source of MDRB transmission.
The aim of this study was to determine the prevalence as well as risk factors of MDRB colonization among HCP.
HCP (n=107) taking part in an antibiotic stewardship program, were voluntarily recruited to perform a rectal swab and to fill in a questionnaire to identify risk factors of MDRB carriage, i.e. being physician, gender, travel abroad within the previous 12 months, vegetarianism, regular consumption of raw meat, contact to domestic animals, household members with contact to livestock, work or fellowship abroad, as well as medical treatment abroad and antibiotic therapy within the previous 12 months.
Selective solid media were used to determine the colonization rate with MRSA, VRE and MDRGN. MDRGN were further characterized by molecular analysis of underlying β-lactamases.
None of the participants had an intestinal colonization with MRSA or VRE. 3.7% of the participants were colonized with extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae, predominantly blaCTX-M type. Neither additional flouroquinolone resistance nor carbapenem resistance was detected in any of these isolates. No risk factors were identified to have a significant impact of MDRB carriage among HCP.
A colonization rate of 3.7% with ESBL-producing Enterobacteriaceae is of interest, but comparing it to previously published data with similar colonization rates in the healthy population in the same geographic area, it is probably less an occupational risk.
The first cultural influences come out in Dobruja together with the appearance of the first German colonists, beginning from 1840 till 1891. The colonization process develops itself in three stages and colonies in places like Tulcea, Malcoci, Almagea, Ciucurova, Cogealac, Tariverde, M. Kogălniceanu and others set up as a result. The German population has created an original culture, an ethnic and spiritual communication being deeply set up, but at the same time a communication struck by the specific conditions imposed by the history of this south-eastern European area. On the other side, the Turkish invasion of Dobruja started earlier, in 1388, when it was actually defeated by Mircea cel Bătrân. In 1393 the Turks succeeded in taking Dobruja and Silistra, but in 1404 Micea cel Bătrân re-conquered the greatest part of these regions. Many Turkish and Tartars moved into Dobruja during the long period of Ottoman rule. The 19th century ethnographic maps show a mainly Turkish population in the area of modern day Dobruja, Tartars and Turks in the southern part of Dobruja and Romanians dominating the north of Dobruja. The paper aims at presenting aspects regarding these two different identities and cultures which are to be found in Dobruja, as well as their integration process within the Romanian Dobrujan modern society.
The demography of the alpine pioneer species Saxifraga aizoides was investigated along a successional gradient at the Rotmoos glacier foreland (2,330–2,450 m a.s.l., Obergurgl, Ötztal, Austria) from recently deglaciated areas to advanced successional stages. A basic hypothesis of our study was that fecundity might play an essential role for population growth rate on the youngest site and become of minor importance at advanced successional stages. A matrix modelling approach was performed to calculate the main demographic parameters on 6, 33, and 81 year old moraines. Our results partly confirmed the prediction of the larger role of fecundity on the youngest sites. Here, seedling mortality was lower compared to the older sites, and the reproductive success was significantly higher. All in all, Saxifraga aizoides mainly follows a "persistence strategy" from the beginning, characterized by the fact that large individuals did not undergo mortality at the recently deglaciated site. However, in the long term a population decline will occur due to plant age and changes of environmental conditions along the successional gradient.
The cattle egret (Bubulcus ibis) has recently colonized Brazil. This process offers an excellent opportunity for the study of colonization and dispersal patterns across extensive areas by non-native birds. The aims of the present investigation were a) to determine the genetic diversity of the cattle egret in Brazil and Africa, b) evaluate genetic differentiation between populations in different regions of Brazil and Africa, and c) detect genetic signs of demographic expansion in these two areas. Mitochondrial DNA (mtDNA) Control Region (CR) sequences were obtained from 112 cattle egrets in four Brazilian and four African (Kenya, Ghana and Nigeria) populations. Genetic diversity (H, h, θ) and population structure (AMOVA, Fst) were assessed and the populations were tested for signs of recent demographic expansion. A total of 35 haplotypes were found: 22 exclusive to Africa, 10 exclusive to Brazil and three shared by both samples. The degree of genetic diversity, determined by mtDNA analysis, was similar between Brazil and Africa, demonstrating that the successful colonization of the non-native area occurred with no significant loss of diversity. The pairwise Fst values among the Brazilian and African populations were all significantly different. The population in southern Brazilian exhibited the lowest degree of differentiation with respect to the African population, followed by the southeastern and northeastern populations of the country. The genetic differentiation data suggest that the colonization of Brazil by the cattle egret began in the southern region and expanded to the southeastern and northeastern regions of the country. This genetic differentiation pattern is in accordance with the higher number of cattle per grazing area in southern Brazil, which may have favored the onset of the successful establishment of the species. The findings indicate that mtDNA genetic diversity was retained during the colonization process and colonization began in the southern region of the country. Moreover, signs of demographic expansion were detected in the African sample.