Untersuchungen zur Induktion von Adhäsion bei Escherichia coli und Salmonella Typhimurium durch murines SPLUNC1 und LPLUNC1

Die überwiegend in den Atemwegen und im Nasenrachenraum exprimierten PLUNCs (palate, lung and nasal epithelium clone) gehören zur Familie der LT (lipid transfer)/LBP (Lipopolysaccharide binding protein)-Proteine und werden in long (L)- und short (S)-PLUNCs (LPLUNC bzw. SPLUNC) unterteilt (Bingle und Craven 2002, Bingle et al. 2004). SPLUNC1 und LPLUNC1 sind die beiden einzigen Mitglieder der PLUNC-Proteinfamilie, die in den oberen Atemwegen (Trachea und Bronchien) exprimiert sind (Bingle und Bingle 2000, Bingle et al. 2010). In dieser Arbeit wurde der Einfluss dieser beiden Proteine auf die Adhäsion verschiedener gramnegativer Bakterien untersucht. Hierzu wurden rekombinant in Insektenzellen exprimiertes murines SPLUNC1 und LPLUNC1 in einem Kristallviolett-Adhäsionstest eingesetzt. Es konnte gezeigt werden, dass die getesteten PLUNC-Proteine bei den meisten Klebsiella pneumoniae-Isolaten sowie bei Serratia marcescens Adhäsion inhibieren. Bei Salmonella Typhimurium und Escherichia coli kommt es dagegen in Anwesenheit von mSPLUNC1 oder mLPLUNC1 zu einer Induktion von Adhäsion über Typ 1 Pili. Ein möglicher Rezeptor für die PLUNC-Proteine auf der Oberfläche der Bakterien ist LPS, da eine Zugabe von exogenem LPS im Adhäsionstest die Induktion von Adhäsion inhibiert. Weiterhin wurde durch Verwendung verkürzter Proteinvarianten gezeigt, dass die Adhäsion-induzierende Domäne von mSPLUNC1 am C-Terminus des Proteins lokalisiert ist. Zur Identifikation von bakteriellen Genen, die an der Induktion von Adhäsion durch die PLUNC-Proteine beteiligt sind, wurde eine Sammlung von S. Typhimurium-Zufallsmutanten im Kristallviolett-Adhäsionstest anlaysiert. Die Ergebnisse dieses Screenings sprechen für eine wichtige Rolle der Sensorkinase ArcB bei der Ausbildung von Typ 1 Pili. Um in zukünftigen Studien mSPLUNC1 auf Proteinebene zu detektieren und zu quantifizieren, wurden ein monoklonaler α-mSPLUNC1-Antikörper und ein polyklonales α-mSPLUNC1-Antiserum erzeugt. Auf Grundlage dieser beiden Antikörper wurde dann ein Sandwich-ELISA etabliert, der eine Quantifizierung von mSPLUNC1 bis zu einer Nachweisgrenze von 500 pg/ml ermöglicht

Saltwater intrusion in Denmark

The studies investigating saltwater intrusion in Denmark have been reviewed to identify the main characteristics and features that have an impact on coastal aquifers interacting with the sea. Traditionally, in regions with wet climate, saltwater intrusion is not appointed as a frequent problem and it is more commonly linked to areas affected by water scarcity. Nevertheless, multiple factors that can induce the salinization of coastal aquifers have been found for Denmark such as the presence of coastal drained lowlands with the water table below the sea level or karstic features and buried valleys in carbonate and detrital systems respectively that can act as preferential flow paths for saline water. Eustatic changes have been also played an important role in the salinization of aquifers, in deep aquifers saline ancient connate water can be identified and in small islands, a delicate equilibrium of freshwater lenses is generated over saline water. As the water supply in this country depends almost exclusively on groundwater, saltwater intrusion can jeopardize fresh groundwater resources in coastal areas. An overview of the cases already studied, questions about the magnitude of these issues and the future perspectives with climate changes are discussed to put into context what is already known and what are the next challenges.Se han revisado los estudios que han investigado la intrusión marina en Dinamarca para identificar las principales características que afectan a los acuíferos costeros en su interacción con el mar. Tradicionalmente, en regiones con clima húmedo, la intrusión marina no es considerada como un problema frecuente ya que se suele asociar con áreas afectadas por la escasez de agua. Sin embargo, se han identificado múltiples factores que pueden generar la salinización de acuíferos costeros en Dinamarca como la presencia de tierras bajas drenadas a lo largo de la costa con niveles freáticos por debajo del nivel del mar o el flujo preferente a través de morfologías kársticas o paleovalles en acuíferos carbonatados o detríticos respectivamente. Los cambios eustáticos han jugado también un papel importante en la salinización de acuíferos, en acuíferos profundos se pueden llegar a identificar aguas connatas antiguas y en islas de reducido tamaño, se establece un delicado equilibrio con lentes de agua dulce sobre aguas salinas. Debido a que este país depende casi exclusivamente de las aguas subterráneas para el abastecimiento de la población, la intrusión marina podría poner en riesgo los recursos subterráneos de agua dulce en las zonas costeras. La revisión de casos estudiados plantea una serie de cuestiones acerca de la magnitud de los problemas existentes y las perspectivas futuras considerando cambios climáticos. Con esta revisión se ha puesto en contexto el estado actual de conocimiento acerca de la intrusión marina en el país y se han identificado los desafíos que podría ser necesario acometer en el futuroNext-Generation EU funding: Programa Maria Zambrano Senior MZSA0

DNAtools: Tools for Analysing Forensic Genetic DNA Data

Development version of the DNAtools R-packag

Magnetic prospection in the Eastern lower city of Artashat-Artaxata in the Ararat Plain of Armenia

In March of 2021, the Berlin-based company cmp continued geophysical prospection works at the ancient city of Artashat-Artaxata (Ararat Province, Armenia). The city was founded by Artashes-Artaxias I in the early 2nd century BC and served as his capital. First magnetic measurements were conducted by the Eastern Atlas company in September 2018. In 2021, during the 5-day survey a total surface of approximately 19.5 ha was investigated by use of the LEA MAX magnetic gradiometer array. This system was configured with seven fluxgate gradiometer probes, similar to the system used in the first survey of 2018. The investigated areas of the Eastern Lower City of Artaxata, located to the south of the investigated field of 2018, had good surface conditions with a moderate amount of sources causing disturbance. However, the general level of the magnetic gradient values measured was significantly lower compared to the 2018 data. Despite the lower magnetic field intensity, a continuation of linear structures towards the south was observed. These lines, most likely reflecting streets and pathways, criss-cross the central part of the Eastern Lower City in a NW–SE and NE–SW direction and exhibit partly positive, partly negative magnetic anomalies. Attached to them, some isolated spots with building remains were identified. The negative linear anomalies point to remains of limestone foundations, as detected in the northern part of the Lower City. The low magnetic intensity and fragmentation of the observed structures are most likely due to severe destruction of the ancient layers by 20th-century earthworks for agricultural purposes. Moreover, the southern part of the surveyed area was affected by major changes caused by modern quarries at Hills XI and XII. In general, the results of the two magnetic prospection campaigns greatly aid our understanding of the archaeological situation in the area of the Eastern Lower City of Artaxata, justifying further investigations that will surely contribute to greater contextualization of the identified archaeological structures. The full data sets are also published in open access on Zenodo

Optimal Design of District Heating Networks with Distributed Thermal Energy Storages – Method and Case Study

District heating systems have a great potential for supporting the energy transition towards a renewa-ble energy system, and could also be an option in less dense populated urban districts and rural communities with a medium heat density. In these cases, distributed thermal energy storages at each building could improve the overall system performance by enabling a leaner sizing of the piping sys-tems due to peak-shaving and reducing the heat losses of the distribution grid. But how can distribut-ed storages already be considered within the design of the district heating network itself? And what are the quantitative benefits with respect to the district heating piping system? This paper answers these questions and presents an open-source optimisation approach for designing the piping network of a district heating system. This includes the optimisation of the network topology, the dimensioning of the pipes, and the consideration of distributed storage options. A linear mixed-integer program-ming model with a high spatial resolution including heat storages at each customer has been imple-mented. Within the QUARREE100 project, the approach is demonstrated on a real world case of an existing district with 129 houses in the provincial town Heide in Northern Germany. In the scenario with 1 m³ heat storages, the thermal losses of the district heating network can be reduced by 10.2 % and the total costs by 13.1 %

Establishment of routine sample preparation protocols at the newly installed MICADAS 14C dating facility at AWI

In November 2016, the first Mini-Carbon-Dating-System (MICADAS) manufactured by Ionplus AG was delivered and installed at the Alfred-Wegener-Institute (AWI), Germany. The new facility includes a graphitization unit (AGE3) connected with an elementar analyser (EA), a carbonate handling system (CHS), and a gas inlet system (GIS). The main goal for the facility at AWI will be the precise and independent dating of carbonaceous materials in marine sediments, sea-ice, and water to address various processes of the global carbon cycling. A particular focus will be on sediments from the high latitude oceans, in which radiocarbon-based age models are often difficult to obtain due to the scarcity of carbonate microfossils. One advantage of the MICADAS is the potential to analyse samples, which contain only a small amount of carbon as CO2 gas. For example, it will be possible to determine 14C ages of samples of foraminifera from carbonate-lean sediments, allowing for paleoclimate reconstructions in key locations for Earth’s climate system such as the Southern ocean. Likewise, compound-specific 14C analyses receive growing attention in carbon cycle studies and require handling of small samples of typically <100µg carbon. The wide range of applications encompassing gas analyses of foraminifera and compound-specific analysis as well as analyses of graphite targets requires establishing routine protocols of various methods of sample preparation, as well as thorough assessment of the respective carbon blanks. We report on our standard procedures for samples of organic matter from sediments or water including carbonate removal, combustion and graphitization using the AGE3 coupled to the EA, as well as on the methodology applied for carbonate samples using the CHS system and the GIS. We have investigated different sample preparation protocols and present the initial results using materials of known age. Additionally, we present the first results of our assessment of process blanks

Gemeinsam forschen, lernen und umsetzen

Etwa ein Drittel des Energieverbrauchs und der CO2-Emissionen entfällt auf Wohn- und Nichtwohngebäude. Mit dem Projekt QUARREE100 wird in Heide (Holst.) eine klimaschonende und resiliente Energieversorgung im Quartier entwickelt und aufgezeigt, um auch in diesem Bereich die Klimaziele zu erreiche