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In the context of the ongoing digitization of interdisciplinary subjects, the need for digital literacy is increasing in all areas of everyday life. Furthermore, communication between science and society is facing new challenges, not least since the COVID-19 pandemic. In order to deal with these challenges and to provide target-oriented online teaching, new educational concepts for the transfer of knowledge to society are necessary. In the transfer project “Zukunftslabor Gesundheit” (ZLG), a didactic concept for the creation of E-Learning classes was developed. A key factor for the didactic concept is addressing heterogeneous target groups to reach the broadest possible spectrum of participants. The concept has already been used for the creation of the first ZLG E-Learning courses. This article outlines the central elements of the developed didactic concept and addresses the creation of the ZLG courses. The courses created so far appeal to different target groups and convey diverse types of knowledge at different levels of difficulty.
Power consumption has become a major design constraint, especially for battery-powered embedded systems. However, the impact of software applications is typically considered in later phases, where both software and hardware parts are close to their finalization. Power-related issues must be detected in early stages to keep the development costs low, satisfy time-to-market, and avoid cost-intensive redesign loops. Moreover, the variety of hardware components, architectures, and communication interfaces make the development of embedded software more challenging. To manage the complexity of software applications, approaches such as model-driven development (MDD) may be used. This article proposes a power-estimation approach in MDD for software application models in early development phases. A unified modeling language (UML) profile is introduced to model power-related properties of hardware components. To determine the impact of software applications, we defined two analysis methods using simulation data and a novel in-the-loop concept. Both methods may be applied at different development stages to determine an energy trace, describing the energy-related behavior of the system. A novel definition of energy bugs is provided to describe power-related misbehavior. We apply our approach to a sensor node example, demonstrate an energy bug detection, and compare the runtime and accuracy of the analysis methods.
Who is more eager to use Gamification in Economic Disciplines? Comparison of Students and Educators
(2022)
Background: In this paper, the focus is on the application of digital and mobile technologies as supporting tools for the implementation of gamification in the field of education of future economists. Objectives: The paper's main objective is to explore whether educators and students are motivated and willing to apply additional technologies as main gamification components in their work and education. Moreover, the paper aims to assess how their more comprehensive application affects the quality of teaching, work flexibility, new learning opportunities, and outcomes. Methods/Approach: The survey method was used to collect answers from educators and students primarily interested in accounting, finance, trade and tourism from higher and secondary education institutions in Croatia, Poland, Serbia and Germany. Afterwards, the responses were compared using statistical methods. Results: Research results confirm that educators and students are willing to use gamification in teaching. Still, they also expressed the need for better administrative support in using particular e-learning tools. Surprisingly, educators are more eager to use gamification in their work than students. Conclusions: The study's general conclusion is that educators and students are both aware of the advantages of using e-learning tools provided through digital and mobile technologies and are eager to implement more gamification in the teaching process. However, continuous education in applying new digital technologies is needed on both sides.
Background
The aim of this qualitative study was to identify a practice level model that could explain a sustained change in nutritional behavior.
Methods
The study used three data inputs from four interviewees, one merged input from a married couple, as narrative interviews. The interviews were analyzed using grounded theory.
Results
Coexistence of a certain suffering and a triggering episode lead to the decision to change nutritional life-style by all interviewed. Maintenance of the self-determined newly learned nutritional behavior was supported by subject-related intrinsic motivation, the ability to reflect, and a low expectation of success from the behavioral change. Environment-related factors were identified as support from life-partner and peers. Subjects reported that the sustained nutritional behavior change impacted their holistic health through subject-perceived improved life quality, increase in the number of social contacts, and a change in personal attitudes and perception. The analysis remains limited, and at best hypothesis generating, in that only three data inputs from four interviewees were used.
Conclusion
In this hypothesis-generating narrative interview study of four study subjects, volition, personal decision making, and long-term motivation (though not external determination) seemed to sustain a change in newly learned nutritional behavior.
A systematic study was performed to understand the effects of the devulcanizing agent dibenzamido diphenyl disulfide (DBD) on the vulcanization and devulcanization process of a sulfur-cured ethylene-propylene-diene monomer (EPDM) rubber. The influence of DBD on vulcanization was investigated by mixing DBD with virgin rubber and curative system. The devulcanization of rubber waste was achieved with varying amounts of DBD ranging from 0.4 to 13.8 wt% and temperatures from 150 to 200°C. The quality of vulcanizates and devulcanizates was evaluated by rheometer tests, temperature scanning stress relaxation measurements, and analysis of mechanical properties. During vulcanization, DBD acts as an accelerator in the presence of sulfur. When accelerators are added, the scorch time increases, and the cure rate decreases. Thus, DBD acts as a retarder. In the presence of activators, DBD leads to a significant reduction of crosslink density. This results in composites with high elongation at break and poor compression set values. The efficiency of the devulcanization of rubber waste depends strongly on DBD concentration and temperature. The monosulfidic crosslinks are cleaved by low concentrations of DBD, while polysulfidic crosslinks require higher concentrations. These results show that DBD is effective as a devulcanizing agent and degrades the network below 200°C.
One challenge of the EU energy transition is the integration of renewable electricity generation in the distribution system. EU energy law proposes a possible solution by introducing “citizen energy communities” (Directive 2019/944/EU) which may be open for “cross-border participation”. This article proposes an innovative way of implementing such cross-border communities by linking distribution systems via a “switchable element”, a generation, storage, or consumption asset with a connection to each country. An optimization model has been developed to calculate the system cost savings of such a connection. Linking regions with complementary characteristics regarding electricity generation and demand via a switchable element leads to more efficient system utilization. Findings are relevant for the transposition of “citizen energy communities” in national laws.
The increasing diversity of cultural backgrounds offers potential for a more elaborated information processing, yet has been shown to be challenging for individuals, due to intergroup hostility, prejudices, and difficulties of intercultural communication. Current research thus focusses on the interaction of employees with different cultural heritages, as well as on their intergroup attitudes and competences. Thereby, leaders have been shown to shape the way diversity is considered in their teams in a top-down process. However, their perception of diversity as well as related challenges and chances are poorly investigated. The current paper thus aims to contribute to the understanding of leader’s perspective on and role in diversity-management by building on a comparative qualitative study with sixteen employees and twenty-two leaders. Research questions are how employees and leaders perceive cultural diversity from their specific point of view, which experiences are likely to contribute to their opinion on and perception of diversity and in how far do employees and leaders differ in these aspects. The results show that employees are aware of the topic of diversity in general but have poor competences in dealing with diversity in their daily working life. This seems to be associated with lack of experience with intercultural interaction and a lack of support from the respective organizations/leaders. Leaders are rarely aware of this lack of support. The results indicate that leaders’ experiences with cultural and age diversity, their identification with the company and previous diversity measures in the context of the companies’ policy towards diversity seem to be relevant for the formation of leaders’ attitudes. As a consequence, most participants focus on the question whether they do or do not want diversity within their teams and companies, while they actually fail to perceive the diversity that is already there.
Oleamide is used as a lubricant in the manufacturing and application of polypropylene (PP) medical devices. Samples of PP were prepared with 0, 1500, and 15 000 ppm oleamide content as lubricant. The samples were either left non-sterile, sterilized with ethylene oxide (ETO), γ-radiation (γ) or autoclaved (A) and stored for up to 4 weeks. To determine the oleamide bulk-to-surface distribution depending on sterilization method and storage time an extraction method and a washing technique were applied. The oleamide content was determined by gas chromatography (GC-FID) and compared with the coefficient of friction (COF). The COF dependent on the measured lubricant content at the surface. The content of lubricant on the surface depends on the type of sterilization: ETO increased the lubricant content to some extent, γ-sterilization and autoclaving reduced it. After storage, no migration of the lubricant to the surface could be detected.
Farmland bird populations are in a deep crisis across Europe. Agri-environment schemes (AES) were implemented by the European Union to stop and reverse the general decline of biodiversity in agricultural landscapes. In Germany, flower strips are one of the most common AES. Establishing high-quality perennial wildflower strips (WFS) with species-rich native forb mixtures from regional seed propagation is a recent approach, for which the effectiveness for birds has not yet been sufficiently studied. We surveyed breeding birds and vegetation on 40 arable fields with WFS (20 with single and 20 with aggregated WFS) and 20 arable fields lacking WFS as controls across Saxony-Anhalt (Germany). Additionally, vegetation composition, WFS quantity and landscape structure (e.g. distance to nearest woody element) were considered in our analyses. All WFS were established with species-rich native seed mixtures (30 forbs) in agricultural practice as AES. Arable fields with WFS had a higher species richness and territory density of birds than controls, confirming the effectiveness of this AES. A forb-rich vegetation was the main driver promoting birds. Flower strip quantity at the landscape level had positive effects only on bird densities, but also single WFS achieved benefits. A short distance from WFS to woody elements increased total bird species richness. However, the density of farmland birds, which are target species of these AES, were negatively affected by the proximity and proportion of woody elements in the vicinity. The effect of the proportion of non-intensively used open habitats and overall habitat richness was unexpectedly low in the otherwise intensively farmed landscape. Species-rich perennial WFS significantly promoted breeding birds. Successful establishment of WFS, resulting in high-quality habitats, a high flower strip quantity as well as implementation in open landscapes were shown to maximise the effectiveness for restoring declining and AES target farmland birds.
Adventitious root (AR) formation is the basis of vegetative propagation in rose, be it via stem cuttings or via stenting. During this process, wounding plays a pivotal role since cell reprogramming takes place at the tissue adjacent to the wound. We investigated the effects of wounding on AR formation on leafy single-node stem cuttings of the rose rootstock R. canina ‘Pfänder’ (codes R02-3 and R02-6) and the cut rose cultivar Rosa ‘Tan09283’ (Registration name ‘Beluga’). Laser wounding treatments were based on the assisted removal of tissue layers located in the bark. The positioning of wounding was studied based on two marking directions: along the cutting base (strip pattern) and around the cutting base (ring pattern). Additionally, the effects of external supply of indole-butyric acid (IBA 1 mg L-1) on rootingwere analyzed. Results showedthat inorder toremovespecific tissue layers, the calculation of the laser energy density (J cm-2) in terms of cutting diameter was necessary. Interestingly, the application of energy densities from 2.5 J cm-2 up to approximately 8.5 J cm-2 were sufficient to expose the tissue layers of epidermis up to regions of phloem. Regarding AR formation for R. canina ‘Pfänder’, characterized by a low rooting response, an increase in the rooting percentage was registered when the laser treatment eliminated the tissue up to phloem proximities. Analysis of the nodal position showed that bud location was a preferential place for AR formation independently of wounding treatment. In case of Rosa ‘Tan09283’, laser treatments did not reduce its high rooting capacity, but an apparent reduction in rooting quality due to an investment in tissue healing was observed when wounding reached deeper layers such as parenchyma and sclerenchyma. Results also showeda strongARformation directly fromwounded regions in case of Rosa ‘Tan09283’ specifically when the woundwas located below the axillary bud. In conclusion, wounding by assisted-elimination of layers by laser can induce positive effects on AR formation of single-node stemcuttings of the rose if energy applied is able to expose phloemproximities,a longitudinalorientation, and relative position to the axillary bud are considered.
In open-field vegetable production, high quantities of soil mineral nitrogen (Nmin) and N-rich crop residues often remain in the field at harvest. After the harvest of crops in autumn, this N can lead to considerable nitrate (NO3−) losses during the subsequent winter leaching period. In four field trials, different tillage depths (3–4, 10, 30 cm) and dates (early autumn, late autumn, early spring) were investigated to reduce N losses after growing spinach in the autumn. In a further treatment, the nitrification inhibitor 3,4-Dimethylpyrazole phosphate (DMPP) was directly applied to the crop residues. Potential N losses were calculated by a balance sheet approach based on Nmin concentration (0–90 cm), measured N mineralization and N uptake by catch crops. By postponing the tillage date from early to late autumn or spring, resprouting spinach stubbles acted as a catch crop, reducing N losses by up to 61 kg ha−1. However, if the spinach biomass collapsed, the N losses increased by up to 33 kg ha−1 even without tillage. The application of DMPP as well as the tillage depth were less effective. Overall, postponing tillage to spring seems to be the most promising approach for reducing N losses during the off-season.
Freshwater ecosystems host disproportionately high numbers of species relative to their surface area yet are poorly protected globally. We used data on the distribution of 1631 species of aquatic plant, mollusc, odonate and fish in 18,816 river and lake catchments in Europe to establish spatial conservation priorities based on the occurrence of threatened, rangerestricted and endemic species using the Marxan systematic conservation planning tool. We found that priorities were highest for rivers and ancient lakes in S Europe, large rivers and lakes in E and N Europe, smaller lakes in NW Europe and karst/limestone areas in the Balkans, S France and central Europe. The a priori inclusion of well-protected catchments resulted in geographically more balanced priorities and better coverage of threatened (critically endangered, endangered and vulnerable) species. The a priori exclusion of well-protected catchments showed that priority areas that need further conservation interventions are in S and E Europe. We developed three ways to evaluate the correspondence between conservation priority and current protection by assessing whether a cathment has more (or less) priority given its protection level relative to all other catchments. Each method found that priority relative to protection was high in S and E Europe and generally low in NW Europe. The inclusion of hydrological connectivity had little influence on these patterns but decreased the coverage of threatened species, indicating a trade-off between connectivity and conservation of threatened species. Our results suggest that catchments in S and E Europe need urgent conservation attention (protected areas, restoration, management, species protection) in the face of imminent threats such as river regulation, dam construction, hydropower development and climate change. Our study presents continental-scale conservation priorities for freshwater ecosystems in ecologically meaningful planning units and will thus be important in freshwater biodiversity conservation policy and practice, and water management in Europe.
The energy transition can be mapped on four levels. While industry and the state should act on the national and international level, most of the energy transition is taking place at the regional and municipal levels. Here the small-scale and decentralized nature of the new energy world is reflected, where customized individual solutions are created.
Information systems (IS) play a central role in promoting corporate sustainability and pro-environmental behavior. This study explores the use of mobile apps for fostering sustainability-oriented corporate culture. It accentuates issues relating to sustainability-oriented corporate culture (RQ1), app meta-requirements as a strategic approach to addressing these issues (RQ2), as well as design and implementation principles (RQ3). Referring to the literature on sustainability apps, gamification, and nudging, our qualitative research design combines an analysis of four corporate apps intending to promote sustainable behavior and expert interviews (Grounded Theory). The proposed framework supports the planning, realization, and monitoring of this targeted app use. Single cultural dimensions inform seven issues in culture development. Five meta-requirements address this multi-dimensionality, challenges provided by new digital working environments, and principles of Green IT. Four design principles support, extend, and integrate current knowledge on app features, nudging, and gamification. Five variables determine the app intervention and maturity level. We conclude that this targeted app use should intend to foster the sustainability orientation within all dimensions of corporate culture instead of being limited to promoting sustainable behavior.
A project was initiated to apply dietary CP reduction under commercial conditions. The main objective was to demonstrate and validate that dietary CP can be reduced without compromising broiler performance in a production system which is already rather efficient. In addition, we wanted to demonstrate the potential of dietary CP reduction on reducing N-excretions especially in the context of German revised regulations and monitoring attempts. Finally, as previous research suggested, few further aspects such as impact of dietary CP reduction on litter quality and quantity, footpad health, change of ingredient inclusion levels and related impact on sustainability impact factors were evaluated.
Background
Citizen energy cooperatives (CECOs) are an important element for realising the transformation of the European energy system from a central system, dominated by a few market players to a decentralized system with the participation of many citizens, in which energy supply is largely based on renewable energy sources. This article identifies success factors that ensure a working organization that is capable of implementing projects to support the energy transition and improving the well-being of citizens.
Methods
The aim of this study is to identify success factors using the example of CECOs in north western Germany through a two-step process. The first step is a literature review to identify success factors of CECOs. Second, 12 semi-structured expert interviews with managers of CECOs are conducted and evaluated by means of a qualitative content analysis. The interviews identified the success factors and barriers of CECOs. The interviews were recorded and transcribed verbatim. The coding process was carried out using a qualitative data analysis software (ATLAS.ti 8.4.5,).
Results
The results show that three factors particular should be present, but can influence each other, to lead to successful CECOs: (1) the CECOs require business models with low complexity, as business models that span different stages of the value chain can overwhelm organizational managers. (2) Committed key individuals must be found and promoted. They need the support of the members. (3) Social and ecological principles are the core values of CECOs. The maintenance and strengthening of social–ecological credibility must be promoted in the public perception.
Conclusions
The results show that CECOs emerge from a strong social cohesion in a society. In addition, local "key individuals" need to be identified and supported. To this end, the framework conditions (e.g., policy, legislation, municipal support, etc.) must be adapted in such a way that these "key individuals" in CECOs are not overburdened. The analysis of the interviews also revealed that political or regulatory barriers are often cited as obstacles to the implementation of community energy projects.
Duckweeds are fast-growing and nutritious plants, which are gaining increased attention in different fields of application. Especially for animal nutrition, alternative protein sources are needed to substitute soybean meal. The current bottleneck is the standardized production of biomass, which yields stable quantities of a defined product quality. To solve this problem, an indoor vertical farm (IVF) for duckweed biomass production was developed. It consists of nine vertically stacked basins with a total production area of 25.5 m2. The nutrient solution, a modified N-medium, re-circulated within the IVF with a maximum flow rate of 10 L min−1. Nutrients were automatically added based on electrical conductivity. In contrast, ammonium was continuously supplied. A water temperature of 23 °C and a light intensity of 105 μmol m−2 s−1 with a photoperiod of 12:12 h were applied. During a 40-day production phase, a total of 35.6 kg of fresh duckweed biomass (equals 2.1 kg of dried product) was harvested from the IVF. On average, 0.9 kg day−1 of fresh biomass was produced. The dried product contained 32% crude protein (CP) and high levels of proteinogenic amino acids (e.g. lysine: 5.42 g, threonine: 3.85 g and leucine: 7.59 g/100 g CP). Biomass of this quality could be used as a protein feed alternative to soybean meal. The described IVF represents a modular model system for duckweed biomass production in a controlled environment and further innovations and upscaling processes.
25-hydroxycholecalciferol (25-OHD3) formed via hepatic hydroxylation from vitamin D, cholecalciferol, represents the precursor of the biologically active vitamin D hormone, 1,25-dihydroxyvitamin D. Due to a higher absorption rate and the omission of one hydroxylation, dietary supplementation of 25-OHD3 instead of vitamin D3 is considered to be more efficient as plasma concentrations of 25-OHD3 are increased more pronounced. The present review summarises studies investigating potential beneficial effects on mineral homeostasis, bone metabolism, health status and performance in sows, piglets and fattening pigs. Results are inconsistent. While most studies could not demonstrate any or only a slight impact of partial or total replacement of vitamin D3 by 25-OHD3, some experiments indicated that 25-OHD3 might alter physiological processes when animals are challenged, for example, by a restricted mineral supply.
To investigate the influence of two dietary sources of vitamin D on the vitamin D status, bone metabolism, welfare and birth progress of gestating and lactating sows, forty-nine multiparous sows were randomly assigned to one of two diets: “CON” (n = 25; 50 μg vitamin D3/kg feed) and “HYD” (n = 24; 50 μg 25-hydroxycholecalciferol/kg feed). The basal diets were protein- and phosphorus-reduced. The trial started on day 3 ante insemination of the sows and ended with weaning of the piglets on day 28 postpartum. Dietary supplementation of 25-hydroxycholecalciferol resulted in improved maternal vitamin D status (p < 0.001), fewer gait changes (p < 0.01) and longer standing time after feeding (day 5 ante partum; p < 0.05) compared to vitamin D3. However, the bone markers CrossLaps and osteocalcin were not affected. Overall, the present results suggest that sows fed 25-hydroxycholecalciferol instead of vitamin D3 showed improved locomotion and stance strength. However, this outcome is probably not related to altered bone metabolism. The underlying mechanisms must be investigated in further studies.
Duckweeds can be potentially used in human and animal nutrition, biotechnology or wastewater treatment. To cultivate large quantities of a defined product quality, a standardized production process is needed. A small-scale, re-circulating indoor vertical farm (IVF) with artificial lighting and a nutrient control and dosing system was used for this purpose. The influence of different light intensities (50, 100 and 150 µmol m−2 s−1) and spectral distributions (red/blue ratios: 70/30, 50/50 and 30/70%) on relative growth rate (RGR), crude protein content (CPC), relative protein yield (RPY) and chlorophyll a of the duckweed species Lemna minor and Wolffiella hyalina were investigated. Increasing light intensity increased RGR (by 67% and 76%) and RPY (by 50% and 89%) and decreased chlorophyll a (by 27% and 32%) for L. minor and W. hyalina, respectively. The spectral distributions had no significant impact on any investigated parameter. Wolffiella hyalina achieved higher values in all investigated parameters compared to L. minor. This investigation proved the successful cultivation of duckweed in a small-scale, re-circulating IVF with artificial lighting.