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Compound flooding, such as the co-occurrence of fluvial floods and extreme coastal water levels (CWL), may lead to significant impacts in densely-populated Low Elevation Coastal Zones. They may overstrain disaster management owing to the co-occurrence of inundation from rivers and the sea. Recent studies are limited by analyzing joint dependence between river discharge and either CWL or storm surges, and little is known about return levels of compound flooding, accounting for the covariance between drivers. Here, we assess the compound flood severity and identify hotspots for northwestern Europe during 1970–2014, using a newly developed Compound Hazard Ratio (CHR) that compares the severity of compound flooding associated with extreme CWL with the unconditional T-year fluvial peak discharge. We show that extreme CWL and stronger storms greatly amplify fluvial flood hazards. Our results, based on frequency analyses of observational records during 2013/2014’s winter storm Xaver, reveal that the river discharge of the 50-year compound flood is up to 70% larger, conditioned on the occurrence of extreme CWL, than that of the at-site peak discharge. For this event, nearly half of the stream gauges show increased flood hazards, demonstrating the importance of including the compounding effect of extreme CWL in river flood risk management.
Many technical challenges still need to be overcome to improve the quality of the green coffee beans. In this work, the wet Arabica coffee processing in batch and continuous modus were investigated. Coffee beans samples as well as by-products and wastewaters collected at different production steps were analyzed in terms of their content in total phenols, antioxidant capacity, caffeine content, organic acids, reducing sugars, free amino group and protein content. The results showed that 40% of caffeine was removed with pulp. Green coffee beans showed highest concentration of organic acids and sucrose (4.96 ± 0.25 and 5.07 ± 0.39 g/100 g DW for the batch and continuous processing). Batch green coffee beans contained higher amount of phenols. 5-caffeoylquinic Acid (5-CQA) was the main constituent (67.1 and 66.0% for the batch and continuous processing, respectively). Protein content was 15 and 13% in the green coffee bean in batch and continuous processing, respectively. A decrease of 50 to 64% for free amino groups during processing was observed resulting in final amounts of 0.8 to 1.4% in the processed beans. Finally, the batch processing still revealed by-products and wastewater with high nutrient content encouraging a better concept for valorization.
We present a novel protocol for the synthesis of enzymatically active microgels. The protocol is based on the precipitation polymerization of N-isopropylacrylamide (NIPAm) in the presence of an enzyme and a protein binding comonomer. A basic investigation on the influence of different reaction parameters such as monomer concentration and reaction temperature on the microgel size and size distribution is performed and immobilization yields are determined. Microgels exhibiting hydrodynamic diameters between 100 nm and 1 mu m and narrow size distribution could be synthesized while about 31-44% of the enzyme present in the initial reaction mixture can be immobilized. Successful immobilization including a verification of enzymatic activity of the microgels is achieved for glucose oxidase (GOx) and 2-deoxy-d-ribose-5-phosphate aldolase (DERA). The thermoresponsive properties of the microgels are assessed and discussed in the light of activity evolution with temperature. The positive correlation of enzymatic activity with temperature for the GOx containing microgel originates from a direct interaction of the enzyme with the PNIPAm based polymer matrix whose magnitude is highly influenced by temperature.
How We Found Our IMU
(2020)
Inertial measurement units (IMUs) are commonly used for localization or movement tracking in pervasive healthcare-related studies, and gait analysis is one of the most often studied topics using IMUs. The increasing variety of commercially available IMU devices offers convenience by combining the sensor modalities and simplifies the data collection procedures. However, selecting the most suitable IMU device for a certain use case is increasingly challenging. In this study, guidelines for IMU selection are proposed. In particular, seven IMUs were compared in terms of their specifications, data collection procedures, and raw data quality. Data collected from the IMUs were then analyzed by a gait analysis algorithm. The difference in accuracy of the calculated gait parameters between the IMUs could be used to retrace the issues in raw data, such as acceleration range or sensor calibration. Based on our algorithm, we were able to identify the best-suited IMUs for our needs. This study provides an overview of how to select the IMUs based on the area of study with concrete examples, and gives insights into the features of seven commercial IMUs using real data.
Over large coastal regions in Greenland and Antarctica the ice sheet calves directly into the ocean. In contrast to ice-shelf calving, an increase in calving from grounded glaciers contributes directly to sea-level rise. Ice cliffs with a glacier freeboard larger than approximate to 100 m are currently not observed, but it has been shown that such ice cliffs are increasingly unstable with increasing ice thickness. This cliff calving can constitute a self-amplifying ice loss mechanism that may significantly alter sea-level projections both of Greenland and Antarctica. Here we seek to derive a minimalist stress-based parametrization for cliff calving from grounded glaciers whose freeboards exceed the 100m stability limit derived in previous studies. This will be an extension of existing calving laws for tidewater glaciers to higher ice cliffs. To this end we compute the stress field for a glacier with a simplified two-dimensional geometry from the two-dimensional Stokes equation. First we assume a constant yield stress to derive the failure region at the glacier front from the stress field within the glacier. Secondly, we assume a constant response time of ice failure due to exceedance of the yield stress. With this strongly constraining but very simple set of assumptions we propose a cliff-calving law where the calving rate follows a power-law dependence on the freeboard of the ice with exponents between 2 and 3, depending on the relative water depth at the calving front. The critical freeboard below which the ice front is stable decreases with increasing relative water depth of the calving front. For a dry water front it is, for example, 75 m. The purpose of this study is not to provide a comprehensive calving law but to derive a particularly simple equation with a transparent and minimalist set of assumptions.
In ecological communities, especially the pelagic zones of aquatic ecosystems, certain bodysize ranges are often over-represented compared to others. Community size spectra, the distributions of community biomass over the logarithmic body-mass axis, tend to exhibit regularly spaced local maxima, called "domes", separated by steep troughs. Contrasting established theory, we explain these dome patterns as manifestations of top-down trophic cascades along aquatic food chains. Compiling high quality size-spectrum data and comparing these with a size-spectrum model introduced in this study, we test this theory and develop a detailed picture of the mechanisms by which bottom-up and top-down effects interact to generate dome patterns. Results imply that strong top-down trophic cascades are common in freshwater communities, much more than hitherto demonstrated, and may arise in nutrient rich marine systems as well. Transferring insights from the general theory of nonlinear pattern formation to domes patterns, we provide new interpretations of past lake-manipulation experiments.
„Wir alle treffen Entscheidungen im Leben, aber letztendlich treffen unsere Entscheidungen uns.“
(2020)
„Wir alle treffen Entscheidungen im Leben, aber letztendlich treffen unsere Entscheidungen uns.“
So erging es den Herausgebern, nachdem sie sich dazu entschlossen hatten, Lehrveranstaltungen an der Universität Potsdam anzubieten, die sich mit dem Medium „Computerspiel“ beschäftigen sollten – und damit auf überraschend große Resonanz stießen. Das Resultat ist vorliegendes Handbuch. Es möchte Eltern, LehrerInnen und MultiplikatorInnen exemplarische Einblicke in die vielschichtigen Welten dieses Phänomens vermitteln. Bei den AutorInnen der Beiträge handelt es sich um EnthusiastInnen aus der Computerspielbranche sowie um videospielbegeisterte SozialarbeiterInnen, KulturwissenschaftlerInnen und LehrerInnen.
“Jewish, Gay and Proud”
(2020)
This publication examines the foundation and institutional integration of the first gay-lesbian synagogue Beth Chayim Chadashim, which was founded in Los Angeles in 1972. As early as June 1974, the synagogue was admitted to the Union of American Hebrew Congregations, the umbrella organization of the Reform congregations in the United States. Previously, the potential acceptance of a congregation by and for homosexual Jews triggered an intense and broad debate within Reform Judaism. The work asks how it was possible to successfully establish a gay-lesbian synagogue at a time when homosexual acts were considered unnatural and contrary to tradition by almost the entire Jewish community. The starting point of the argumentation is, in addition to general changes in American synagogues after World War II, the assumption that Los Angeles was the most suitable place for this foundation. Los Angeles has an impressive queer history and the Jewish community was more open, tolerant and innovative here than its counterpart on the East Coast. The Metropolitan Community Church was also founded in the city, and as the largest religious institution for homosexual Christians, it also served as the birthplace of queer synagogues.
Reform Judaism was chosen as the place of institutional integration of the community because a relative openness for such an endeavor was only seen here. Responsa written in response to a potential admission of Beth Chayim Chadashim can be used to understand the arguments and positions of rabbis and psychologists regarding homosexuality and communities for homosexual Jews in the early 1970s.
Ultimately, the commitment and dedication of the congregation and its heterosexual supporters convinced the decision-makers in Reform Judaism. The decisive impulse to question the situation of homosexual Jews in Judaism came from Los Angeles. With its analysis, the publication contributes to the understanding of Queer Jewish History in general and queer synagogues in particular.
Young kale and pea leaves are rich in secondary plant metabolites (SPMs) whose profile can be affected by ultraviolet B (UVB) radiation. Carotenoids and flavonoids in kale and pea exposed to narrow-banded UVB, produced by innovative light-emitting diodes (LEDs), and subsequently used for breadmaking were investigated for the first time, thus combining two important strategies to increase the SPMs intake. Breads were also fortified with protein-rich lentil flour. Antioxidant activity in the ‘vegetable breads’ indicated health-promoting effects. Lentil flour increased the antioxidant activity in all of the ‘vegetable breads’. While carotenoids and chlorophylls showed a minor response to UVB treatment, kaempferol glycosides decreased in favor of increasing quercetin glycosides, especially in kale. Additionally, breadmaking caused major decreases in carotenoids and a conversion of chlorophyll to bioactive degradation products. In ‘kale breads’ and ‘pea breads’, 20% and 84% of flavonoid glycosides were recovered. Thus, kale and pea leaves seem to be suitable natural ingredients for producing innovative Functional Foods.
Immunological responses of hibernating mammals are suppressed at low body temperatures, a possible explanation for the devastating effect of the white-nose syndrome on hibernating North American bats. However, European bats seem to cope well with the fungal causative agent of the disease. To better understand the immune response of hibernating bats, especially against fungal pathogens, we challenged European greater mouse-eared bats (Myotis myotis) by inoculating the fungal antigen zymosan. We monitored torpor patterns, immune gene expressions, different aspects of the acute phase response and plasma oxidative status markers, and compared them with sham-injected control animals at 30 min, 48 h and 96 h after inoculation. Torpor patterns, body temperatures, body masses, white blood cell counts, expression of immune genes, reactive oxygen metabolites and non-enzymatic antioxidant capacity did not differ between groups during the experiment. However, zymosan injected bats had significantly higher levels of haptoglobin than the control animals. Our results indicate that hibernating greater mouse-eared bats mount an inflammatory response to a fungal challenge, with only mild to negligible consequences for the energy budget of hibernation. Our study gives a first hint that hibernating European bats may have evolved a hibernation-adjusted immune response in order to balance the trade-off between competent pathogen elimination and a prudent energy-saving regime.