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The present study was performed aiming to investigate a large number and a wide variety of mosquitoes from various regions of Germany for the presence of defined groups of parasites. Accordingly, during three successive years between 2010 and 2012, more than 140.000 mosquitoes, trapped at various sites in Germany, were characterized and analysed. The selected trapping sites, most of them located in southwest and northeast Germany, are known tor their abundant occurrence of mosquitoes, such as the foodplains of the river Isar. In addition, some of them represent important stepping stones for migrating birds, such as the Lake Chiemsee or the Lake Constance. The mosquitoes were characterized on the basis of morphological criteria. The results indicated, that the main autochthonous species generally present in Germany were trapped, in particular abundant species such as Aedes vexans and Culex pipiens s. l.. As morphological criteria do not allow the discrimination of members of the Culex pipiens complex or between females of Culex pipiens and Culex torrentium, a multiplex real-time PCR was developed for the rapid genetic differentiation of the various Culex species and biotypes. Using this method, hybrids of Cx. pipiens pipiens biotype pipiens and biotype molestus were detected in Germany for the first time. These hybrids are known as important bridge vectors for the transmission of West Nile virus from birds to humans. To fascilitate the detection of parasites in such a large number of mosquio samples within a reasoonable period of time, further multiplex real-time PCR assays were developed to allow analyses of respective microbial DNAs by high-throughput screening. The results indicated that a considerable number of German mosquitoes are carrying filariae. In this context, a new filarial species was detected, occuring primarily in southern Germany. The reservoir of this new filarial species is probably birds, as it was detected mainly in ornithophilic mosquitoes. Studies on Dirofilaria immitis, Dirofilaria repens as well as Onchocerca lupi, three zoonotic filarial species endemis in southern Europe and pathofenic for humans, revealed the detection of a focus of stable transmission of D. repens in the federal state of Brandenburg. This rilarial species was detected in several mosquito catches from 2011 and 2012, along the Oder Valley in the vincinity of the town of Eberswalde. As there were reports on cases of avian malaira in the zoo of Heidelberg in 2010 screening of mosquitoes was extended for the presence of Haemosporidia, such as Haemoproteus sp., Leukocytozoon sp. or Plasmodium sp.. A multiplex real-time PCR was developed able to detect nematodes as well as blood protozoans. Depending on the catchment area, more than 70 % of the mosquitoes were positive for at least one of the two groups of parasites.

Aim To examine associations of pre-diabetes and well-controlled diabetes with periodontitis. Materials and Methods The Study of Health in Pomerania (SHIP)-Trend is a cross-sectional survey in North-Eastern Germany including 3086 participants (49.4% men; age 20–82 years). Clinical attachment loss (CAL) and periodontal probing depth (PPD) were assessed applying a random half-mouth protocol. The number of teeth was determined. Pre-diabetes comprised impaired fasting glucose and impaired glucose tolerance. Previously known diabetes was defined as well controlled if glycated haemoglobin (HbA1c) was <7.0%. Participants were categorized as follows: normal glucose tolerance (NGT), pre-diabetes, newly detected type 2 diabetes (T2DM), known T2DM with HbA1c<7.0% and known T2DM with HbA1c≥7.0%. Results Pre-diabetes was neither associated with mean CAL and PPD in multivariable adjusted linear regression models nor with edentulism (OR = 1.09 (95%-CI: 0.69-1.71)) and number of teeth (OR = 0.96 (95%-CI: 0.75–1.22), lowest quartile versus higher quartiles) in logistic regression models. Associations with mean CAL and edentulism were stronger in poorly controlled previously known diabetes than in well-controlled previously known diabetes (for edentulism: OR = 2.19 (95%-CI: 1.18–4.05), and OR = 1.40 (95%-CI: 0.82–2.38), respectively, for comparison with NGT). Conclusions Periodontitis and edentulism were associated with poorly controlled T2DM, but not with pre-diabetes and well-controlled diabetes.

Unter den verschiedenen additiven Fertigungsverfahren stellt das selektive Laserschmelzen (SLM) eine optimale Technologie für die Herstellung von metallischen Bauteilen mit komplexen Geometrien und hervorragenden Eigenschaften dar. SLM-Bauteile werden Schicht für Schicht mit hochenergetischen Laserstrahlen hergestellt, was das SLM flexibler als konventionelle Produktionstechnologien wie das Gießen macht. Die beim SLM auftretenden schnellen Aufheiz-/Kühlraten können zu deutlich unterschiedlichen Gefügen im Vergleich zu herkömmlichen Herstellungsverfahren führen. Die beim SLM entstehenden Hochtemperaturgradienten können sich weiterhin positiv auf die Gefügeentstehung (Phasenbildung, Morphologie, …) und damit auf die mechanischen Eigenschaften der SLM-Bauteile auswirken. Darüber hinaus können die mit SLM gefertigten Teile mit der Notwendigkeit einer minimalen Nachbearbeitung in den Einsatz genommen werden. Bisher wurden mehrere Studien zu den Parametern: Optimierung oder Verarbeitung von Verbundwerkstoffen mit fehlerfreien Teilen durchgeführt Die Scanstrategie hat dabei einen besonders großen Einfluss bei der Materialbearbeitung durch die additive Fertigung. Die Optimierung der Scanstrategie ist daher von zentraler Bedeutung für die Synthese von Materialien mit verbesserten physikalischen und mechanischen Eigenschaften. Diese Arbeit untersucht die Wirkung von vier verschiedenen Scanning-Strategien auf das Gefüge und das mechanische Verhalten von 316L Edelstahl, synthetisiert durch selektives Laserschmelzen (SLM). Die Ergebnisse deuten darauf hin, dass die Scanstrategie einen vernachlässigbaren Einfluss auf die Phasenbildung und die Art des Gefüges hat, die während der SLM-Verarbeitung entsteht: Austenit ist die einzige Phase, die sich bildet, und alle Proben weisen eine zelluläre Morphologie auf. Die Scanstrategie beeinflusst jedoch erheblich die charakteristische Größe von Zellen und Körnern, die wiederum der Hauptfaktor für die Festigkeit unter Zugbelastung zu sein scheint. Andererseits haben Eigenspannungen offenbar keinen Einfluss auf die quasi-statischen mechanischen Eigenschaften der Proben. Das mit einem Streifenmuster mit Konturstrategie hergestellte Material weist das feinste Gefüge und die beste Kombination mechanischer Eigenschaften auf: Streckgrenze und Bruchdehnung liegen bei 550 MPa und 1010 MPa und die plastische Verformung bei über 50 %. Ein weiterer wichtiger Aspekt für die Anwendung des mittels SLM synthetisierten 316L-Stahls ist seine thermische Stabilität. Daher wurde der Einfluss des Glühens bei verschiedenen Temperaturen (573, 873, 1273, 1373 und 1673 K) auf die Stabilität der Phasen, der Zusammensetzung und des Gefüges des 316L-Edelstahls untersucht, der unter Verwendung des Streifenmuster mit Konturstrategie hergestellt wurde. Darüber hinaus wurden die durch die Wärmebehandlung induzierten Veränderungen genutzt, um die entsprechenden Variationen der mechanischen Eigenschaften der Proben unter Zugbelastung zu verstehen. Das Glühen hat keinen Einfluss auf die Phasenbildung: Bei allen hier untersuchten Proben wird ein einphasiger Austenit beobachtet. Darüber hinaus ändert das Glühen nicht die zufällige kristallographische Orientierung, die im Material nach der Synthese beobachtet wird. Das komplexe zelluläre Gefüge mit feinen Subkornstrukturen, die für die as-SLM-Proben im Ausgangszustand charakteristisch sind, ist bis zu 873 K stabil. Die Zellgröße nimmt mit steigender Glühtemperatur zu, bis das zelluläre Gefüge bei hohen Temperaturen nicht mehr beobachtet werden kann (T ≥ 1273 K). Die Festigkeit der Proben nimmt mit steigender Glühtemperatur durch die mikrostrukturelle Vergröberung ab. Die ausgezeichnete Kombination von Festigkeit und Duktilität des Materials im Ausgangszustand ist auf das komplexe zelluläre Gefüge und die Subkörner sowie die Fehlausrichtung zwischen Körnern, Zellen, Zellwänden und Subkörnern zurückzuführen. Mit dem Ziel, das mechanische Verhalten des 316L-Stahls weiter zu verbessern, wird der Einfluss harter Partikel einer zweiten Phase auf das Gefüge und die damit verbundenen mechanischen Eigenschaften untersucht. Dazu wurde mittels SLM ein Verbund aus einer 316L-Stahlmatrix und 5 Vol.% CeO2-Partikeln hergestellt. Die SLM-Parameter, die zu einer fehlerfreien 316L-Matrix führen, sind für die Herstellung von 316L/CeO2-Verbundproben nicht geeignet. Hochdichte Verbundproben können jedoch durch sorgfältige Einstellung der Laserscangeschwindigkeit unter Beibehaltung der anderen Parameter prozessiert werden. Die Zugabe der CeO2-Verstärkung verändert die Phasenbildung nicht, beeinflusst aber das Gefüge des Verbundwerkstoffs, welches im Vergleich zum partikelfreien 316L-Material deutlich verfeinert ist. Das verfeinerte Gefüge bewirkt eine signifikante Verstärkung im Verbund, ohne die plastische Verformung zu beeinträchtigen. Die Analyse des Einflusses einer zweiten Phase wird fortgesetzt, indem untersucht wird, wie TiB2-Partikel das Gefüge und die mechanischen Eigenschaften eines 316L-Edelstahls beeinflussen, der durch selektives Laserschmelzen hergestellt wird. Das für die unverstärkte 316L-Matrix charakteristische komplexe zelluläre Gefüge mit feinen Subkörnern ist in allen Proben zu finden. Die Zugabe der TiB2-Partikel reduziert die Größe der Körner und Zellen erheblich. Darüber hinaus sind die TiB2-Partikel in der 316L-Matrix homogen dispergiert und bilden kreisförmige Ausscheidungen mit einer Größe von etwa 50-100 nm entlang der Korngrenzen. Diese mikrostrukturellen Merkmale führen zu einer signifikanten Verfestigung im Vergleich zu den unverstärkten 316L-Proben. Diese Ergebnisse belegen, dass SLM erfolgreich zur Synthese von Verbundwerkstoffen aus dem Edelstahl 316L mit herausragenden mechanischen Eigenschaften im Vergleich zu einer unverstärkten 316L-Stahlmatrix eingesetzt werden kann. Dies könnte dazu beitragen, den Einsatz von SLM bei der Herstellung von Stahlmatrix-Verbundwerkstoffen für die Automobilindustrie, die Luft- und Raumfahrt und zahlreiche andere Anwendungen zu erweitern. Among the different additive manufacturing processes, selective laser melting (SLM) represents an optimal choice for the fabrication of metallic components with complex geometries and superior properties. SLM parts are built layer-by-layer using high-energy laser beams, making SLM more flexible than conventional processing techniques, like casting. The fast heating/cooling rates occurring during SLM can result in remarkably different microstructures compared with conventional manufacturing processes. The high-temperature gradients characterising SLM can also have a positive effect on the microstructures and, in turn, on the mechanical properties of the SLM parts. Additionally, the SLM parts can be put into use with the necessity of minimal post-processing treatments. To date, a number of studies have been devoted to the parameters optimization or processing of composite materials with defect-free parts. The scanning strategy is one of the most influential parameters in materials processing by additive manufacturing. Optimization of the scanning strategy is thus of primary importance for the synthesis of materials with enhanced physical and mechanical properties. Accordingly, this thesis examines the effect of four different scanning strategies on the microstructure and mechanical behaviour of 316L stainless steel synthesized by selective laser melting (SLM). The results indicate that the scanning strategy has negligible influence on phase formation and the type of microstructure established during SLM processing: austenite is the only phase formed and all specimens display a cellular morphology. The scanning strategy, however, considerably affects the characteristic size of cells and grains that, in turn, appears to be the main factor determining the strength under tensile loading. On the other hand, residual stresses apparently have no influence on the quasi-static mechanical properties of the samples. The material fabricated using a stripe with contour strategy displays the finest microstructure and the best combination of mechanical properties: yield strength and ultimate tensile strength are about 550 and 1010 MPa and plastic deformation exceeds 50 %. Another important aspect for the application of 316L steel synthesized by SLM is its thermal stability. Therefore, the influence of annealing at different temperatures (573, 873, 1273, 1373 and 1673 K) on the stability of phases, composition and microstructure of 316L stainless steel fabricated by using the stripe with contour strategy has been investigated. Moreover, the changes induced by the heat treatment have been used to understand the corresponding variations of the mechanical properties of the specimens under tensile loading. Annealing has no effect on phase formation: a single-phase austenite is observed in all specimens investigated here. In addition, annealing does not change the random crystallographic orientation observed in the as-synthesized material. The complex cellular microstructure with fine subgrain structures characteristic of the as-SLM specimens is stable up to 873 K. The cell size increases with increasing annealing temperature until the cellular microstructure can no longer be observed at high temperatures (T ≥ 1273 K). The strength of the specimens decreases with increasing annealing temperature as a result of the microstructural coarsening. The excellent combination of strength and ductility exhibited by the as-synthesized material can be ascribed to the complex cellular microstructure and subgrains along with the misorientation between grains, cells, cell walls and subgrains. With the aim of further improving the mechanical behaviour of 316L steel, this works examines the effect of hard second-phase particles on microstructure and related mechanical properties. For this, a composite consisting of a 316L steel matrix and 5 vol.% CeO2 particles was fabricated by SLM. The SLM parameters leading to a defect-free 316L matrix are not suitable for the production of 316L/CeO2 composite specimens. However, highly-dense composite samples can be synthesized by carefully adjusting the laser scanning speed, while keeping the other parameters constant. The addition of the CeO2 reinforcement does not alter phase formation, but it affects the microstructure of the composite, which is significantly refined compared with the unreinforced 316L material. The refined microstructure induces significant strengthening in the composite without deteriorating the plastic deformation. The analysis of the effect of a second phase is continued by investigating how TiB2 particles influence the microstructure and mechanical properties of a 316L stainless steel synthesized by selective laser melting. The complex cellular microstructure with fine subgrains characteristic of the unreinforced 316L matrix is found in all samples. The addition of the TiB2 particles reduces significantly the sizes of the grains and cells. Furthermore, the TiB2 particles are homogeneously dispersed in the 316L matrix and they form circular precipitates with sizes around 50-100 nm along the grain boundaries. These microstructural features induce significant strengthening compared with the unreinforced 316L specimens. These findings prove that SLM can be successfully used to synthesize 316L stainless steel matrix composites with overall superior mechanical properties in comparison with the unreinforced 316L steel matrix. This might help to extend the use of SLM to fabricate steel matrix composites for automotive, aerospace and numerous other applications.

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Background and ObjectiveTo evaluate phenotypic and genetic relationships between migraine and lipoprotein subfractions.MethodsWe evaluated phenotypic associations between migraine and 19 lipoprotein subfraction measures in the Women's Genome Health Study (n = 22,788). We then investigated genetic relationships between these traits using summary statistics from the International Headache Genetics Consortium for migraine (ncase = 54,552, ncontrol = 297,970) and combined summary data for lipoprotein subfractions (n up to 47,713).ResultsThere was a significant phenotypic association (odds ratio 1.27 [95% confidence interval 1.12–1.44]) and a significant genetic correlation at 0.18 (p = 0.001) between migraine and triglyceride-rich lipoproteins (TRLPs) concentration but not for low-density lipoprotein or high-density lipoprotein subfractions. Mendelian randomization (MR) estimates were largely null, implying that pleiotropy rather than causality underlies the genetic correlation between migraine and lipoprotein subfractions. Pleiotropy was further supported in cross-trait meta-analysis, revealing significant shared signals at 4 loci (chr2p21 harboring THADA, chr5q13.3 harboring HMGCR, chr6q22.31 harboring HEY2, and chr7q11.23 harboring MLXIPL) between migraine and lipoprotein subfractions. Three of these loci were replicated for migraine (p < 0.05) in a smaller sample from the UK Biobank. The shared signal at chr5q13.3 colocalized with expression of HMGCR, ANKDD1B, and COL4A3BP in multiple tissues.ConclusionsThe study supports the association between certain lipoprotein subfractions, especially for TRLP, and migraine in populations of European ancestry. The corresponding shared genetic components may help identify potential targets for future migraine therapeutics.Classification of EvidenceThis study provides Class I evidence that migraine is significantly associated with some lipoprotein subfractions.

AbstractInteractions between seabirds and commercial fishing activities have been well documented but little information is available regarding the impacts of more traditional fishing practices on seabird populations. We interviewed fishermen, administered questionnaires, and made field-based observations to determine the extent to which artisanal fisheries interact with and affect seabirds in the fjords and channels of the Chonos archipelago in southern Chile. Our surveys indicated a positive perception of seabirds as useful indicators of marine productivity and in their role scavenging fish waste and discards associated with fishing operations. However, the surveys also revealed that fishermen routinely establish seasonal camps for collecting seabird eggs and adults for food or bait and introduce feral predators to seabird breeding colonies on islands. Understanding the traditional practices of fishermen is critical for the future of community-based conservation of the region's marine resources and biodiversity.

Background Tumor biopsy is not essential for the diagnosis of hepatocellular carcinoma (HCC); however, grading remains important for the prognosis. Purpose To investigate whether combined Gd-EOB-DTPA and gadobutrol liver magnetic resonance imaging (MRI) can predict HCC grading. Material and Methods Thirty patients (66.6 ± 7.3 years) with histologically confirmed HCC (grade 1, n = 5; grade 1–2, n = 6; grade 2, n = 13; grade 2–3, n = 2; grade 3, n = 4) underwent two liver MRIs, one with gadobutrol and one with Gd-EOB-DTPA, on consecutive days. Blinded to grading, two radiologists reviewed the gadobutrol and Gd-EOB-DTPA images in consensus with respect to: (i) HCC hyper-/iso-/hypointensity in the arterial, portal-venous/delayed, and Gd-EOB-DTPA hepatocellular phase; and (ii) morphologic tumor features (encapsulated growth, vessel invasion, heterogeneity, liver capsule infiltration, satellite metastases). Results A significant correlation with grading was not found for either the combined dynamic information of all gadobutrol phases (r = −0.187, P = 0.331) or all the Gd-EOB-DTPA phases (r = 0.052, P = 0.802). No correlation with grading was found for a combination of arterial and hepatocellular phase in Gd-EOB-DTPA MRI (r = 0.209, P = 0.305), a combination of both arterial phases (gadobutrol and Gd-EOB-DTPA) with the Gd-EOB-DTPA hepatocellular phase (r = 0.240, P = 0.248), or a combination of all available gadobutrol and Gd-EOB-DTPA phases (r = 0.086, P = 0.691). For all gadobutrol information (dynamic phases and morphology; r = 0.049, P = 0.801) and for all Gd-EOB-DTPA information (r = 0.040, P = 0.845), no correlation with grading was found. Hepatocellular Gd-EOB-DTPA phase iso-/hyperintensity never occurred in grade 3 HCCs. Conclusion Histological HCC grading cannot be predicted by combined Gd-EOB-DTPA/gadobutrol MRI. However, Gd-EOB-DTPA hepatocellular phase iso-/hyperintensity was never detected in grade 3 HCCs.

Ultimately, the structure and functioning of marine ecosystems is defined by the transfer of autotrophic production to higher trophic levels and selective consumption of these autotrophs by predators. Hence, feeding regulation via modification of grazing and food incorporation by predators is critical for understanding and predicting the dynamics of ecosystems. In marine ecosystem and biogeochemical models, feeding regulation by consumers is assumed to be mainly dictated by food quality (Q), which is determined using food quality modules (FQMs) that mimic a consumers’ ability to anticipate fitness consequences for feeding on specific prey items. Current FQMs are based on frameworks that a priori identify specific food components, usually nitrogen (N), and/or phosphorus, as limiting. This negates the importance of consumer physiology, and ignores biochemical constrains on the limiting role of chemical elements in animal production. To help address these problems, we propose a new adaptive approach that bases Q on consumers’ capacity for food uptake and metabolic physiology. Uniquely, it (i) has separate pathways for the utilisation of carbon (C) associated with proteins, lipids and carbohydrates, (ii) considers stage-specific structural biochemical requirement of animals, and (iii) does not treat consumers’ structural demand for carbon as a “unitary requirement” but discriminates among the required biochemical forms of carbon. The approach is applicable to all heterotrophs. In the example given here the model has been configured to represent the calanoid copepod Acartia tonsa. Consistent with experimental observation, but unlike previous models, our model predicts the relationship between Q and food C:N to be unimodal with a maximum Q only at the threshold C:N for biomass production. Results suggest that prey C:N ratios may be irrelevant for food quality due to macromolecular biochemical constrains on the utilisation of chemical elements. This result emphasizes the importance of biochemical substances in animal nutrition and production as well as the necessity of developing food quality models able to adapt to the biochemical needs of the consumer.

The European Union (EU) is often hailed as one of the most successful peace projects in the history of humankind. Indeed, since its inception more than 70 years ago, the EU has made unparalleled contributions to the advancement of peace and reconciliation on the European continent. Despite these successes, the EU integration process faces increasing challenges, including the unprecedented departure of one of its members. Further, one of the greatest tests to European cohesion has proved to be the refugee and migrant crisis, which has revealed fault lines over not only migration but also broader issues of identity, norms, and values. In the wake of this crisis, the Visegrad Group— comprised of Hungary, Poland, Slovakia, and the Czech Republic—presented viewpoints that deviated from those held by most Western European states and EU institutions, thus prompting debates about the emergence of a new East–West divide within Europe. Intrigued by whether the notion of solidarity has a different meaning for those who were present at the birth of the EU as opposed to those who joined more than half a century later, this study strives to uncover the Visegrad countries’ understanding of and approach to European solidarity. Making the case that states’ behavior is a result of varying national characteristics deeply rooted within their national identities, it develops an analytical framework for investigating the nexus between identity and solidarity. Applying this framework to the Visegrad states’ responses to the refugee and migrant crisis and their positions and preferences regarding further enlargement of the EU yields three pivotal conclusions. First, the Visegrad states’ identification with the European project as well as their interpretation of the EU’s norms and values, such as that of solidarity, are contingent upon their respective national identities and historical experiences. Second, the particular composition and interaction of identity elements activated in political discourse can explain varying solidarity profiles among different states as well as possible variances in a single state’s behavior across multiple policy areas. And third, the Visegrad states share a great number of similar identity elements, yet often differ in their manifestation or degree of expression. By taking a more nuanced look at the Visegrad cooperation, this study challenges the widespread impression of the Visegrad Group as a homogeneous bloc. The findings make clear that even the same identity element with a slightly different manifestation can lead to different decisions. At the same time, geographical proximity, cultural similarities, and shared historical experience function as a “magnet” that draws the Visegrad states closer together, unites them in their policy preferences, and ensures the continuation of the Visegrad cooperation. In sum, the present study advances the understanding of the process of European integration and the Visegrad Group’s multifaceted role in it.