Publications by authors named "Merz R"

To understand the complex interplay of topography and surface chemistry in wetting, fundamental studies investigating both parameters are needed. Due to the sensitivity of wetting to miniscule changes in one of the parameters it is imperative to precisely control the experimental approach. A profound understanding of their influence on wetting facilitates a tailored design of surfaces with unique functionality.

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Tuning of the wetting behavior of metallic surfaces by chemical and topographical modification has become popular in recent years. Still, there is a lack in the understanding of fundamental relations between intrinsic properties of the material and its resulting water contact angle. It is widely accepted in the literature that transitions from a hydrophilic to increasingly hydrophobic behavior upon exposure to ambient conditions happen due to the adsorption of adventitious hydrocarbons.

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The aim of the study was to longitudinally evaluate the association between MMP-2, MMP-9, TIMP-1 and chest radiological findings in COVID-19 patients. COVID-19 patients were evaluated based on their hospital admission (baseline) and three months after hospital discharge (T post) and were stratified into ARDS and non-ARDS groups. As a control group, healthy donors (HD) were enrolled.

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The EU Water Framework Directive (WFD) has emphasized that altered stream/river morphology and diffuse pollution are the two major pressures faced by European water bodies at catchment scales. Increasing efforts have been directed toward restoration to meet WFD standards for ecological health, but this work has achieved limited success. One challenge is that little is known about how morphological changes (i.

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Article Synopsis
  • Anomalies in river flood frequencies, either too many or too few floods, skew flood risk estimates and hinder effective climate adaptation efforts.
  • Observations from 1960-2010 indicate that changes in flood generation processes, rather than just extreme rainfall, significantly contribute to these anomalies across Europe.
  • A small shift in how rainfall interacts with soil (from dry to wet) has increased flood-rich periods in the Atlantic and resulted in flood-poor periods in the Mediterranean, indicating that these trends may worsen with climate change, affecting flood management strategies.
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Static contact angle measurements are one of the most popular methods to analyze the wetting behavior of materials of any kind. Although this method is readily applicable without the need of sophisticated machinery, the results obtained for the very same material may vary strongly. The sensitivity of the measurement against environmental conditions, sample preparation and measurement conduction is a main factor for inconsistent results.

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Successful osseointegration, i.e. the fully functional connection of patient's bone and artificial implant depends on the response of the cells to the direct contact with the surface of the implant.

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In the search for achieving ultra-low friction for applications in extreme environments, we evaluate the interfacial processes of diamond/tungsten sliding contacts using an on-line macro-tribometer and a micro-tribometer in an ultra-high vacuum. The coefficient of friction for the tests with the on-line tribometer remained considerably low for unlubricated sliding of tungsten, which correlated well with the relatively low wear rates and low roughness on the wear track throughout the sliding. Ex situ analysis was performed by means of XPS and SEM-FIB in order to better understand the underlying mechanisms of low friction and low-wear sliding.

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The development of quantum technologies is one of the big challenges in modern research. A crucial component for many applications is an efficient, coherent spin-photon interface, and coupling single-color centers in thin diamond membranes to a microcavity is a promising approach. To structure such micrometer thin single-crystal diamond (SCD) membranes with a good quality, it is important to minimize defects originating from polishing or etching procedures.

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The fossil record of the terminal Ediacaran Period is typified by the iconic index fossil Cloudina and its relatives. These tube-dwellers are presumed to be primitive metazoans, but resolving their phylogenetic identity has remained a point of contention. The root of the problem is a lack of diagnostic features; that is, phylogenetic interpretations have largely centered on the only available source of information-their external tubes.

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The infiltration of untreated wastewater into aquifers highly endangers the availability of fresh-water for human consumption in semi-arid areas. This growing problem of potable water scarcity urgently requires solutions for groundwater protection. Decision support systems for local wastewater treatments in settlements already exist.

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Climate change has led to concerns about increasing river floods resulting from the greater water-holding capacity of a warmer atmosphere. These concerns are reinforced by evidence of increasing economic losses associated with flooding in many parts of the world, including Europe. Any changes in river floods would have lasting implications for the design of flood protection measures and flood risk zoning.

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A wide variety of processes controls the time of occurrence, duration, extent, and severity of river floods. Classifying flood events by their causative processes may assist in enhancing the accuracy of local and regional flood frequency estimates and support the detection and interpretation of any changes in flood occurrence and magnitudes. This paper provides a critical review of existing causative classifications of instrumental and preinstrumental series of flood events, discusses their validity and applications, and identifies opportunities for moving toward more comprehensive approaches.

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Article Synopsis
  • Sustainable water basin management needs a clear understanding of river flow patterns affected by human activity.
  • Hydrological models are used to evaluate flow in ungauged areas, but developing these models can be resource-intensive, prompting decision-makers to use existing models.
  • This study found that while flow magnitude indicators are reliable at medium to high flows, other indicators like timing and duration face significant uncertainties, impacting ecological assessments, especially in areas with no prior flow data.
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Elevated nitrate concentrations are a thread for water supply and ecological integrity in surface water. Nitrate fluxes obtained by standard monitoring protocols at the catchment outlet strongly integrate spatially and temporally variable processes such as mobilization and turnover. Consequently, inference of dominant nitrate sources is often problematic and challenging in terms of effective river management and prioritization of measures.

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We apply new perspectives on how organisms burrow by examining the association of variation in sediment mechanical properties with burrowing ability and species distribution of two sympatric lugworms, and We quantified the sediment's resistance to penetration and its grain size distribution at sites inhabited by each species. individuals were found in significantly harder to penetrate, more heterogeneous sediments. We compared worm burrowing ability using reciprocal transplant experiments.

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This study analyses how indicators of water quality (thirteen physico-chemical variables) and drivers of change (i.e., monthly aggregated air temperature and streamflow, population density, and percentage of agricultural land use) coevolve in three large European river basins (i.

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A warming climate is expected to have an impact on the magnitude and timing of river floods; however, no consistent large-scale climate change signal in observed flood magnitudes has been identified so far. We analyzed the timing of river floods in Europe over the past five decades, using a pan-European database from 4262 observational hydrometric stations, and found clear patterns of change in flood timing. Warmer temperatures have led to earlier spring snowmelt floods throughout northeastern Europe; delayed winter storms associated with polar warming have led to later winter floods around the North Sea and some sectors of the Mediterranean coast; and earlier soil moisture maxima have led to earlier winter floods in western Europe.

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