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Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of small, mature CD5

Climate change and decreasing biodiversity are currently hot topics in the media. Freshwaters in the alpine region are good indicators of climate change and, hence, perfect examples for illustrating these threats. Here, we want to share our idea for a Geocaching path (similar to the popular treasure hunt game) that is used to educate the public about the biology of freshwaters. We want to educate the visitors about the natural environment and the consequences of climate change and decreasing biodiversity for our aquatic ecosystems and livelihoods. In particular, we want to show the approaches of scientists to understand and predict these threats and, furthermore, how our society can find solutions to protect aquatic ecosystems. Lake Lunz is a very popular place for tourists. Visitors enjoy walks around the lake as well as swimming. Close by is also one of the oldest lake research stations (WasserCluster Lunz - Biologische Station), where scientists from all over the world are currently conducting on aquatic ecosystems. The project received funding from the EGU Public Engagement Grant in 2019. The GPS coordinates for the Geocache (a small treasure box in an insect hotel) are hidden in the answers to several questions about freshwater biology that lead the participants around the lake, a search we termed "Biogeocaching". The answers can be found on different informational signs that are set up around the lake and at the experimental sites and research facilities of WasserCluster Lunz. After finishing the path, the participants will have learned about ecology of alpine lakes and the research activities at WasserCluster Lunz. We think that geocaching as a treasure hunt is a playful way for people of all ages to discover nature. The combination of an outdoor recreational activity with information about freshwaters, climate change, and decreasing biodiversity -Biogeocaching - will sensitize the public to and raise awareness of these hot topics in the field of Earth Sciences. We hope to encourage other researchers and research institutes to develop something similar on their topic and research.

Purpose: The underlying molecular mechanisms of thymic epithelial malignancies (TEMs) are poorly understood. Consequently, there is a lack of efficacious targeted therapies and patient prognosis remains dismal, particularly for advanced TEMs. We sought to investigate protumorigenic mechanism relevant to this understudied cancer.Experimental Design: Recently established cell lines derived from thymic epithelial tumors were used as a model system. The antitumor activity of specific heat shock protein 90 (Hsp90) inhibitors was investigated by an analysis of cell viability, cell cycle, and apoptosis using MTT-assays and flow cytometry. Western blotting was used to investigate the altered expression of Hsp90 clients. Pharmacological inhibitors against select Hsp90 clients, as well as RNAi, were employed to test the relevance of each client independently. Tissue microarray analysis was performed to match the in vitro findings with observations obtained from patient-derived samples.Results: Hsp90 inhibition significantly reduces cell viability of thymic carcinoma cells, induces cell cycle arrest and apoptosis, and blocks invasiveness. Hsp90 inhibition triggers the degradation of multiple oncogenic clients, for example insulin-like growth factor 1 receptor (IGF-1R), CDK4, and the inactivation of PI3K/Akt and RAF/Erk signaling. Mechanistically, the IGF/IGF-1R–signaling axis contributes to the establishment of the antiapoptotic phenotype of thymic cancer cells. Finally, IGF-1R is overexpressed in advanced TEMs.Conclusions: We have unraveled a novel protumorigenic mechanism in TEMs, namely Hsp90-capacitated overexpression of IGF-1R, which confers apoptosis evasion in malignant thymic epithelial cells. Our data indicate that Hsp90 inhibition, which simultaneously blocks multiple cancer hallmarks, represents a therapeutic strategy in TEMs that may merit evaluation in clinical trials. Clin Cancer Res; 17(8); 2237–49. ©2011 AACR.

Supplementary Figures S1-S8; Supplementary Methods; Supplementary Tables S1-S3.

Dissolved organic matter (DOM) in terrestrial groundwater is generally low in concentration compared to inland surface waters. However, the overall amount of groundwater DOM is huge, as there is 100 times more fresh groundwater than fresh surface water. To date, research on groundwater DOM has merely focused on specific threats to humans such as e.g. DOM and heavy metal complexations and DOM from hydrocarbon contamination. A comprehensive, large-scale study of groundwater is still missing. Here, we examine DOM properties in a large-scale approach with regards to surface characteristics such as land use and altitude, aquifer characteristics as well as microbial features. We analyzed 1600 water samples from 100 groundwater bodies all over Austria with regards to their DOM quantity, quality and bacterial abundance (BA). DOM quality was evaluated with self-organizing maps on fluorescence excitation-emission-matrices (EEMs) combined with Ward clustering and subsequent parallel factor analysis to describe DOM properties of each cluster. We evaluated how these clusters differed among each other, based on DOC and nitrate concentrations, BA and selected environmental characteristics. Our results show that fluorescence components in groundwater resemble components found in other groundwater studies, in studies from forest streams, the dark ocean, agricultural catchments and wastewater treatment plants. The latter fluorescence components were associated with a cluster that is characterized by agricultural and urban land use, as well as by high nitrate concentrations. Clusters with an increased abundance of high-molecular weight and humic components, commonly associated with vascular plant and soil origin, correlated with a higher bacterial abundance. This observation provides evidence that elevated numbers of suspended bacteria mainly originate from the surface. Our study shows that DOM fluorescence can be a fast monitoring tool to identify aquifers under anthropogenic stress and delineate sensitive recharge areas with high surface-groundwater interaction.

Understanding hydrological flow variability and quantification of groundwater recharge rates have been two of the cornerstones of sustainable water management for decades. The cause-and-effect relationship between flow variability and groundwater recharge is mainly dependent on climate type, for example Mediterranean climates vs tropical climates. Each climate type, has historically been predictable, for example mean annual temperature, temperature amplitude, mean annual precipitation and precipitation seasonality, implying that the system could be modelled so long as there were sufficient data records. However, two of the most commonly cited consequences of climate change are extreme weather events and hydroclimatic instability. Both processes break down the “predictable” component of hydro-climatic modelling and require a re-evaluation of both how models are set up for simulation of the hydrological system in any given location as well as the data needed to support these simulations. In short, are our current models ready for a dynamic climate and the associated hydrological system change? Adapting to this changed climate reality requires a multifaceted approach that integrates environmental parameters (temperature, evaporation, precipitation), hydrological tracers (e.g., water isotopes), hydro-climatic indices but also incorporates anthropogenic impacts (e.g., water impoundments). Often these parameters/tracers are governed by data constraints at the spatial (e.g., point data) and temporal scale (data continuity). In this contribution we examine the results of rainfall-runoff modelling in southern Africa where soil-moisture-deficit-index was used to show that headwater drought is a key indicator of severe oncoming dry conditions. In particular, changes in precipitation seasonality required the recalibration of model parameters for ‘wet’ and ‘dry’ periods in order to make the model adaptable to unpredictable climate variability. In spite of multiple calibration efforts, the temporal uncertainty remained significant due to anthropogenic changes in the system being modelled, for example water diversions into dams and abstractions for irrigation, changes that are likely to increase in the future. Stable water isotopes are sensitive tracers of the impact of climate change on hydrological flow because they are natural constitutes of water and their partitioning is strongly dependent on temperature. The integration of temperature sensitive hydrological tracers like water isotopes and along with other hydro-climatic indices within hydrological modelling systems can advance the development of flexible modelling tools that better accommodate climate variability. Doing so however, requires an assessment of what data records will be needed in the future, and taking steps to ensure that the collections of these datasets are prioritized.

Streams and rivers metabolize dissolved organic matter (DOM). Although most DOM compounds originate from natural sources, recreational use of rivers increasingly introduces chemically distinct anthropogenic DOM. So far, the ecological impact of this DOM source is not well understood. Here, we show that a large music festival held adjacent to the Traisen River in Austria increased the river’s dissolved organic carbon (DOC) concentration from 1.6 to 2.1 mg L–1 and stream ecosystem respiration from −3.2 to −4.5 mg L–1. The DOC increase was not detected by sensors continuously logging absorbance spectra, thereby challenging their applicability for monitoring. However, the fluorescence intensity doubled during the festival. Using parallel factor analysis, we were able to assign the increase in fluorescence intensity to the chemically stable UV-B filter phenylbenzimidazole sulfonic acid, indicating organic compounds in sunscreen and other personal care products as sources of elevated DOC. This observation was confirmed by liquid chromatography coupled with mass spectrometry. The elevated respiration is probably fueled by anthropogenic DOM contained in beer and/or urine. We conclude that intense recreational use of running waters transiently increases the anthropogenic DOM load into stream ecosystems and alters the fluvial metabolism. We further propose that chemically distinct, manmade DOM extends the natural range of DOM decomposition rates in fluvial ecosystems.

The abstract is available here: https://uscholar.univie.ac.at/o:1648326

Nitrate stable isotopes provide information about nitrate contamination and cycling by microbial processes. The Fischa-Dagnitz (Austria) spring and river system in the agricultural catchment of the Vienna basin shows minor annual variance in nitrate concentrations. We measured nitrate isotopes (δ15N, δ18O) in the source spring and river up to the confluence with the Danube River (2019–2020) with chemical and water isotopes to assess mixing and nitrate transformation processes. The Fischa-Dagnitz spring showed almost stable nitrate concentration (3.3 ± 1.0 mg/l as NO3–-N) year-round but surprisingly variable δ15N, δ18O-NO3– values ranging from +5.5 to +11.1‰ and from +0.5 to +8.1‰, respectively. The higher nitrate isotope values in summer were attributed to release of older denitrified water from the spring whose isotope signal was dampened downstream by mixing. A mixing model suggested denitrified groundwater contributed > 50 % of spring discharge at baseflow conditions. The isotopic composition of NO3– in the gaining streams was partly controlled by nitrification during autumn and winter months and assimilation during the growing season resulting in low and high δ15N-NO3– values, respectively. NO3– isotope variation helped disentangle denitrified groundwater inputs and biochemical cycling processes despite minor variation of NO3– concentration.

Hydrological events mobilize chemically diverse dissolved organic matter (DOM) from soils to streams. Further, such events can also cause an influx of soil microbial life into fluvial systems. Here we present results from the HYDRO-DIVERSITY project, which aims to investigate the dynamic transfer of DOM and microbial life from catchment soils to streams, as well as their downstream fate. We studied the microbial community composition and DOM quality using 16S Illumina sequencing and fluorescence and absorbance spectroscopy. Data from small streams showed strong changes in DOM composition and in the microbial community delivered from soils during hydrological events. Moreover, we performed a flume experiment, in which soil microbial inoculation and the processing of DOM across different biofilm ages were evaluated. As such, biofilm age did not directly affect the establishment of soil microbes in the stream ecosystem. However, in-stream processing of soil DOM appeared to be affected by the inoculation event. This poses the fundamental question, if the processing of DOM in streams and rivers depends on the transient presence of specific soil microbes in stream ecosystems. Overall our results show that soils provide a dynamic and relevant influx of microbes and DOM to first order streams and that this dynamic influx likely affects microbial community dynamics of downstream fluvial networks as well as in-stream DOM processing.

Climate change and decreasing biodiversity are currently hot topics in the media. Freshwaters in the alpine region are good indicators of climate change and, hence, perfect examples for illustrating these threats. Here, we want to share our idea for a Geocaching path (similar to the popular treasure hunt game) that is used to educate the public about the biology of freshwaters. We want to educate the visitors about the natural environment and the consequences of climate change and decreasing biodiversity for our aquatic ecosystems and livelihoods. In particular, we want to show the approaches of scientists to understand and predict these threats and, furthermore, how our society can find solutions to protect aquatic ecosystems.Lake Lunz is a very popular place for tourists. Visitors enjoy walks around the lake as well as swimming. Close by is also one of the oldest lake research stations (WasserCluster Lunz – Biologische Station), where scientists from all over the world are currently conducting on aquatic ecosystems. The project received funding from the EGU Public Engagement Grant in 2019. The GPS coordinates for the Geocache (a small treasure box) will be hidden in the answers to several questions about freshwater biology that will lead the participants around the lake, a search we termed “Biogeocaching”. The answers can be found on different informational signs that will be set up around the lake and at the experimental sites and research facilities of WasserCluster Lunz. After finishing the path, the participants will have learned about ecology of alpine lakes and the research activities at WasserCluster Lunz.We think that geocaching as a treasure hunt is a playful way for people of all ages to discover nature. The combination of an outdoor recreational activity with information about freshwaters, climate change, and decreasing biodiversity –Biogeocaching - will sensitize the public to and raise awareness of these hot topics in the field of Earth Sciences. We hope to encourage other researchers and research institutes to develop something similar on their topic and research.

The stream hyporheic zone (HZ) represents the interface between streams and groundwater. Due to the mixing of organic matter and nutrients from groundwater and surface waters it is a hot spot of microbial activities and carbon processing within a stream network. The magnitude of terrestrial carbon degradation by microorganisms in the HZ influences the quantity and biochemical quality of terrestrial carbon as well as greenhouse gas concentrations in streams. One of the factors controlling microbial activities and terrestrial carbon degradation in the HZ are nutrients. However, major knowledge gaps exist regarding the control of nutrients on terrestrial carbon processing in the HZ among different streams.We investigated the role of algal DOM (DOMalg) and phosphorus (P) on the degradation of soil DOM (DOMsoil) by hyporheic microorganisms in a lab- and a field-based experiment. In the lab-based experiment, we focused on the influence of different DOMsoil:DOMalg ratios on the DOM degradation at similar carbon concentrations in microcosms mimicking the HZ. One batch was incubated at ambient P concentrations and a second batch at increased P concentrations adapted to the highest levels found in the pure DOMalg. We assessed microbial respiration and changes in DOM optical properties to examine quantitative and qualitative changes of the DOM pool. In the field-based experiment, we determined microbial respiration rates of HZ-sediments from 20 streams in Austria with differing ambient nutrient and organic carbon concentrations. The sediments were incubated with DOMsoil, with and without additional P.Results from the lab-based experiment show that microbial respiration in the HZ decreased with increasing soil DOM fractions. When P levels were adapted to DOMalg concentrations, microbial respiration rates were comparable between the different DOM mixtures and DOMsoil was degraded. However, in the field-based experiment, P addition only stimulated microbial respiration rates in one out of 20 HZ-sediments, suggesting that microbial respiration rates are not solely controlled by P.In conclusion, nutrient pulses can stimulate microbial activities and thus terrestrial carbon degradation in the HZ. However, when using different stream HZ-sediments, it becomes evident that the nutrient stimulation is not a ubiquitous mechanism and terrestrial carbon degradation in the HZ is controlled by a multitude of factors.

Dissolved organic matter (DOM) in fresh groundwater is generally low in concentration compared to other fresh waters. However, the overall amount of groundwater DOM is huge, as there is 100 times more fresh groundwater than fresh surface water. To date, research on groundwater DOM has merely focused on specific threats to humans such as e.g. DOM and heavy metal complexations and DOM from hydrocarbon contamination. Only few studies targeted to understand DOM as energy source of groundwater food webs and the role of groundwater DOM in the global carbon cycle. While research on these two subjects in surface waters flourish, a comprehensive, large-scale study of groundwater is still missing. Since a major fraction of Earth’s microbial biomass is found in the subsurface, mainly in aquifers, this represents a major knowledge gap. Moreover, researchers found that groundwater DOM concentrations worldwide increase alarmingly. Here, for the first time, we examine DOM properties and heterogeneity in a large-scale approach with regards to aquifer characteristics and physical-chemical as well as microbial features. We hypothesize that groundwater DOM quality shows high diversity and plays an important, yet complex role in these ecosystems, where bioavailability is influenced by intrinsic molecular properties, as well as environmental conditions.We analyzed 1000 water samples from 100 groundwater bodies all over Austria with regards to their DOM quantity, quality and bacterial abundance (BA). From fluorescence excitation-emission-matrices (EEMs) we derived indices and components to describe DOM quality. Next, we explored this data with principal component analysis, where we used convex-hull areas to estimate the heterogeneity of DOM composition within the groundwater bodies. In parallel, the similarity of DOM quality was evaluated with self-organizing maps on EEMs to test if we captured the heterogeneity of the data set sufficiently with the previous analysis. DOM quantity and quality was then related to BA and physical-chemical parameters.Our results show that water from fractured and karstic aquifers exhibit significantly higher terrestrial DOM origin and less degraded DOM than porous aquifers. This result can be explained by abiotic factors such as adsorption of large, aromatic compounds, as well as biological factors, specifically, larger surface areas for biofilm development in porous aquifers. The latter is supported by our observation that porous aquifers showed higher BA values. Remarkably, we found that BA was related to different DOM quality in each aquifer type: In porous aquifers BA was related to large, aromatic DOM molecules indicating that these are important for bacterial growth, while in fractured and karstic aquifers BA was related to fulvics and highly degraded humic compounds. Bacterial growth and degradation of complex DOM might be limited by low retention times in some of these aquifers. Also, we found that groundwater bodies located in river valleys display high heterogeneity in DOM quality spanning across the whole DOM compositional diversity found in this study. This finding could either be explained by surface water infiltration in some parts and younger groundwater or the fact that river valleys are main settlement areas.

Ziel dieser Arbeit ist es, neue Erkenntnisse zur Bildung lyotroper SmC*-Phasen zu gewinnen und einen elektroklinen Effekt in chiral lamellaren Phasen nachzuweisen.

The recent discovery of a new lyotropic liquid crystal phase, the structure and properties of which are analogous to the chiral ferroelectric smectic C-phase (SmC*) in thermotropics, was based on a tailored amphiphile structure in which a tilt-promoting mesogenic core was linked to a chiral diol-headgroup via a hydrophilic ethylene glycol spacer [J. R. Bruckner et al., Angew. Chem., Int. Ed., 2013, 52, 8934–8937]. However, so far there is only one example of this general amphiphile structure known to form the new lyotropic SmC* phase in mixtures with water and with formamide. In an attempt to systematically elucidate the underlying structure–property relations we now report two new amphiphiles leading to lyotropic SmC* phases. These amphiphiles are derived from the parent amphiphile structure by (i) an elongation of the hydrophilic ethylene glycol spacer and (ii) an exchange of the original 2-phenylpyrimidine core by an even more tilt-promoting fluorenone core. Our investigations also reveal that the formation of the lyotropic SmC* phase is highly sensitive to exchanging or enlarging a building block of the primary material.

Hydrology is the main driver of dissolved organic matter (DOM) dynamics in intermittent rivers and ephemeral streams. However, it is still unclear how the timing and the spatial variation in flow connectivity affect the dynamics of DOM and inorganic solutes. This study focuses on the impact of flow cessation on the temporal and spatial heterogeneity of DOM quantity and quality along an intermittent stream. We monitored a headwater intermittent stream at high spatial and temporal frequencies during a summer drying episode and analysed dissolved organic carbon (DOC) and its spectroscopic properties, inorganic solutes and dissolved CO2. The drying period determined the disruption of the fluvial continuum with a recession of stream continuum at a rate of ~60 m/d and the gradual formation of a patched system of isolated pools of different sizes. Our results showed that the period of time that had elapsed since isolated pool formation (CI-days) was an essential factor for understanding how drying shaped the biogeochemistry of the fluvial system. Overall, drying caused a high DOC concentration and an increase in the humic-like fluorescence signal. Additionally, solutes showed contrasting responses to hydrological disconnection. Electrical conductivity, for instance, is a clear “sentinel” of the fragmentation process because it starts to increase before the hydrological disruption occurs. In contrast, DOC, most spectroscopic DOM descriptors and CO2 showed delayed responses of approximately 5–21 days after the formation of isolated pools. Furthermore, the spatial location and volume of each isolated pool seemed to exert a significant impact on most variables. In contrast, the temperature did not follow a clear pattern. These findings indicate that the fragmentation of longitudinal hydrological connectivity does not induce a single biogeochemical response but rather stimulates a set of solute-specific responses that generates a complex biogeochemical mosaic in a single fluvial unit.

This thesis attempts to clarify how the authors incorporated their theological beliefs in their writing to more clearly discover, although modern audiences often enjoy both authors, why Charlotte Bronte was unimpressed with Jane Austen. The thesis is an examination of the ways in which Jane Austen and Charlotte Bronte interact with the Evangelical Reformation within the Anglican Church in their novels Mansfield Park and Jane Eyre, respectively. Both authors, as daughters of Anglican clergymen, were aware of and influenced by the movement, but at varying degrees. This project begins with a brief explanation of the state of the Anglian Church and beginnings of the Evangelical Reformation. The thesis then examines George Austen's influence on his daughter and the characters and text of Mansfield Park to observe the ways in which traditional Anglicanism and tenets of Evangelicalism are discussed in the novel, revealing more clearly where Austen's personal beliefs aligned. Similarly, the project then analyzes Patrick Bronte's influence on Charlotte Bronte and evaluates the characters and text of Jane Eyre to mark the significance of the Evangelical movement on Charlotte Bronte. After studying these works and religious components of their lives, the thesis argues that Austen's traditionally Anglican subtlety with the subject of religion did not appeal to Bronte's passion for the subject, clearly inspired by the Evangelical Reformation. Master of Arts Charlotte Brontë was unimpressed with the writing of Jane Austen, which is surprising as the audience for one author usually also enjoys the other author as well. Although the specific reason for Brontë’s distaste for Austen is unknown, this thesis proposes that Brontë disagreed with how Austen portrayed Evangelicalism. Both Brontë and Austen were Anglican clergymen’s daughters, and they both grew up with an awareness of the Evangelical Reformation occurring in the Anglican Church. Brontë was influenced by the movement more, which this thesis shows after first outlining the Evangelical Reformation, exploring Austen’s relationship with it and how it appears in Mansfield Park, and then examining Brontë’s relationship with the Reformation and how it appears in Jane Eyre as well. This thesis contains brief historical and biographical sketches of the authors and their families, literary examinations of the novels Mansfield Park and Jane Eyre to study how the authors interacted with the Evangelical ideals, and an analysis that looks at faith in these two novels in a comparative way to explain why Brontë might have disagreed with and therefore disliked Austen’s writing.

1. Microbial heterotrophic activity is a major driver of nutrient and organic matter processing in the hyporheic zone of headwater streams. Additionally, the hypor‐ heic zone might provide refuge for microbes when surface flow ceases during drought events. 2. We investigated chemical (organic and inorganic nutrients) and microbiological parameters (bacterial cell concentration, live–dead ratios, and extracellular en‐ zyme activities) of surface and interstitial pore water in a period of progressive surface-hyporheic disconnection due to summer drying. The special situation of the chosen study reach, where groundwater mixing is impeded by the bedrock forming a natural channel filled with sediment, allowed as to study the transfor‐ mation of these parameters along hyporheic flow paths. 3. The chemical composition of the hyporheic pore water reflected the connectivity with the surface water, as expressed in the availability of nitrate and oxygen. Conversely, microbiological parameters in all hyporheic locations were different from the surface waters, suggesting that the microbial activity in the water changes rapidly once the water enters the hyporheic zone. This feature was prin‐ cipally manifested in higher live–dead ratios and lower leucine aminopeptidase (an activity related to nitrogen acquisition) in the hyporheic pore waters. 4. Overall, bacterial cell concentration and extracellular enzyme activities increased along hyporheic flow paths, with a congruent decrease in inorganic nutrients and dissolved organic matter quantity and apparent molecular size. 5. Our findings show two important functions of the hyporheic zone during drought: (1) deeper (−50 cm) water-saturated layers can act as a refuge for microbial activity; and (2) the hyporheic zone shows high rates of carbon and nitrogen turnover when water residence times are longer during drought. These rates might be even enhanced by an increase in living microbes in the remaining moist locations of the hyporheic zone FP7 People: Marie-Curie Actions, Grant/ Award Number: 607150; FP7 Environment, Grant/Award Number: 603629-ENV-6.2.1