‘Finding Old Sikyon’, 2015: A preliminary report

The project “Ancient Sikyon” is a cooperation between the Ephorate of Antiquities of Corinth, the National Museum of Denmark, the Danish Institute at Athens and the Institute of Geoscience of the Christian-Albrechts University of Kiel. Conceived as a five-year project, its main aim is to identify the exact location, the major features and the urbanistic development of the city, prior to its relocation in 303 BC to a plateau nearby. This, however, is intended to serve the greater purpose of answering general questions of Archaic and Classical urbanism and the structure and organization of a famous centre of art and culture in comparison with other such centres like Corinth and Athens. The first year of research has already brought important information about the topography and material culture of Ancient Sikyon, which is presented in this preliminary report

Human monocytes subjected to ischaemia/reperfusion inhibit angiogenesis and wound healing in vitro

Objectives The sequence of initial tissue ischaemia and consecutive blood flow restoration leads to ischaemia/reperfusion (I/R) injury, which is typically characterized by a specific inflammatory response. Migrating monocytes seem to mediate the immune response in ischaemic tissues and influence detrimental as well as regenerative effects during I/R injury. Materials and methods To clarify the role of classical monocytes in I/R injury, isolated human monocytes were subjected to I/R in vitro (3 hours ischaemia followed by 24 hours of reperfusion). Cellular resilience, monocyte differentiation, cytokine secretion, as well as influence on endothelial tube formation, migration and cell recovery were investigated. Results We show that I/R supported an enhanced resilience of monocytes and induced intracellular phosphorylation of the prosurvival molecules Erk1/2 and Akt. FACS analysis showed no major alteration in monocyte subtype differentiation and surface marker expression under I/R. Further, our experiments revealed that I/R changes the cytokine secretion pattern, release of angiogenesis associated proteins and MMP-9 activity in supernatants of monocytes exposed to I/R. Supernatants from monocytes subjected to I/R attenuated endothelial tube formation as indicator for angiogenesis as well as endothelial cell migration and recovery. Conclusion In summary, monocytes showed no significant change in cellular integrity and monocyte subtype after I/R. Functionally, monocytes might have a rather detrimental influence during the initial phase of I/R, suppressing endothelial cell migration and neoangiogenesis

Large expert-curated database for benchmarking document similarity detection in biomedical literature search

Document recommendation systems for locating relevant literature have mostly relied on methods developed a decade ago. This is largely due to the lack of a large offline gold-standard benchmark of relevant documents that cover a variety of research fields such that newly developed literature search techniques can be compared, improved and translated into practice. To overcome this bottleneck, we have established the RElevant LIterature SearcH consortium consisting of more than 1500 scientists from 84 countries, who have collectively annotated the relevance of over 180 000 PubMed-listed articles with regard to their respective seed (input) article/s. The majority of annotations were contributed by highly experienced, original authors of the seed articles. The collected data cover 76% of all unique PubMed Medical Subject Headings descriptors. No systematic biases were observed across different experience levels, research fields or time spent on annotations. More importantly, annotations of the same document pairs contributed by different scientists were highly concordant. We further show that the three representative baseline methods used to generate recommended articles for evaluation (Okapi Best Matching 25, Term Frequency-Inverse Document Frequency and PubMed Related Articles) had similar overall performances. Additionally, we found that these methods each tend to produce distinct collections of recommended articles, suggesting that a hybrid method may be required to completely capture all relevant articles. The established database server located at https://relishdb.ict.griffith.edu.au is freely available for the downloading of annotation data and the blind testing of new methods. We expect that this benchmark will be useful for stimulating the development of new powerful techniques for title and title/abstract-based search engines for relevant articles in biomedical research.Peer reviewe

Geophysical Prospection of Archaeological Sites on the Northern Peloponnese, Greece: Geological and Urban Challenges

Despite 20 years of many developments, challenges remain for geophysical prospection of archaeological sites; two of these challenges are investigated in this thesis on case studies from the archaeological sites Aigeira and Sikyon; the geological setting and urban environments. These challenges can be overcome through various multi-method approaches depending on the region as shown on a series of case studies. However, this work also includes an extensive multi-method geophysical study focused on an enigmatic subsurface structure that could be interpreted as either prehistoric chamber tombs or complex, highly heterogeneous weathering patterns. This work demonstrates how shear-wave seismics and full-waveform inversion (FWI) can be used in archaeological prospecting to distinguish between different interpretive models. Since it is able to reveal a highly heterogeneous subsurface that is characterized by linear cracks on a decimeter scale. The second main case study highlights the challenge of a large-scale seismic prospection in an urban area. Even in the urban environment of modern Kiato, active seismic surveys in search of Sikyon's silted-up harbor basin have, in principle, been successfully conducted. Due to the too disturbing factors of the urban environment, passive ambient noise recording methods were tested. This thesis shows that the horizontal-to-vertical spectral ratio (HVSR) method can be used as a substitute of refraction seismics to map the depth of the first layer interface over large areas after establishing a relationship between the HVSR resonance frequency and refractor depth. The analysis of arrays (beamforming) of very small aperture arrays consisting of 9 stations proved capable to image the subsurface in similar resolution as does MASW. Hence, this method can be seen as a substitute to the Love-wave analysis for determining shear-wave velocities in an urban environment

IR spectroscopy : suitable method for determination of curing degree and crosslinking type in melamine-formaldehyde resins

Melamine–formaldehyde (MF) resins are widely used as adhesives and finishing materials in the wood industry. During resin cure, either methylene ether or methylene bridges are formed, leading to the formation of a three‐dimensional resin network. Not only the curing degree, but also the chemical species present in the cured resin determine the quality of the final product. Analytical methods allowing a detailed investigation of network formation are of great benefit to manufacturers. In the present work, resin cure of an MF precondensate is studied at different temperatures (100–200 °C) without considering the initial pH as a factor. Isoconversional kinetic analysis based on exothermal curing enthalpies enables calculation of the crosslinking degree at a given time/temperature regime. A semiquantitative determination of the chemical groups present is performed based on solid‐state nuclear magnetic resonance data. Fourier transform infrared spectroscopy has shown to be a fast and reliable analytical tool with high sensitivity toward functional groups and with great potential for at‐line process control

Self-healing of densely crosslinked thermoset polymers : a critical review

Structural and functional thermosetting composite materials are exposed to different kinds of stress which can damage the polymer matrix, thus impairing the intended properties. Therefore, self-healing materials have attracted the attention of many research groups over the last decades in order to provide satisfactory material properties and outstanding product durability. The present article provides a critical overview of promising self-healing strategies for crosslinked thermoset polymers. It is organized in two parts: an overview about the different approaches to self-healing is given in the first part, whereas the second part focuses on the specific chemistries of the main strategies to achieve self-healing through crosslinking. It is attempted to provide a comprehensive discussion of different approaches which are described in the scientific literature. By comparison of the advantages and disadvantages, the authors wish to provide helpful insights on the assessment of the potential to transfer the extensive present knowledge about self-healing materials and methods to surface varnishing thermoset coatings