Most European water bodies fail to meet good ecological status, largely due to excessive phosphorus (P) concentrations. Despite policy efforts, little improvement has occurred over the past 15 years. To put the situation into historical perspective, this study investigates long-term human impacts on riverine P concentrations by modelling P export throughout the Holocene. Three approaches were compared: a spatially lumped nutrient export coefficient (EC) model, a spatially explicit sediment export model adapted for P export (WaTEM/SEDEM), and a hindcasting model based on population density. Model outputs were validated using present-day total phosphorus (TP) concentrations and a Holocene TP time series derived from dated floodplain sediments.Results indicate that land cover change alone may have triggered eutrophication as early as 2000 years ago, well before the widespread use of mineral fertilizers. Erosion mobilized P naturally present in soils and concentrated by human activity. Both the EC and WaTEM/SEDEM models suggest that historical exceedances of the freshwater TP threshold (140 μg L-1) have occurred, with critical land cover thresholds ranging from 17% to 46%. Population-based estimates indicate this threshold was crossed around 300 years ago at ∼56 inhabitants km-2. Predicted pristine TP concentrations ranged from 6 [95% CI: 4–8] μg L-1 (WaTEM/SEDEM) to 35 [18–124] μg L-1 (EC), while sediment records suggest 48 μg L-1. The intricate link between water quality, land use change, and human population dynamics is crucial to consider for effective future water quality management.

As a network of researchers we release an open-access database (EUSEDcollab) of water discharge and suspended sediment yield time series records collected in small to medium sized catchments in Europe. EUSEDcollab is compiled to overcome the scarcity of open-access data at relevant spatial scales for studies on runoff, soil loss by water erosion and sediment delivery. Multi-source measurement data from numerous researchers and institutions were harmonised into a common time series and metadata structure. Data reuse is facilitated through accompanying metadata descriptors providing background technical information for each monitoring station setup. Across ten European countries, EUSEDcollab covers over 1600 catchment years of data from 245 catchments at event (11 catchments), daily (22 catchments) and monthly (212 catchments) temporal resolution, and is unique in its focus on small to medium catchment drainage areas (median = 43 km(2), min = 0.04 km(2), max = 817 km(2)) with applicability for soil erosion research. We release this database with the aim of uniting people, knowledge and data through the European Union Soil Observatory (EUSO).

In the context of the European Erasmus+ project Teaching ASTronomy at the Educational level (TASTE), we investigated to what extent secondary school students of four participating countries (Belgium, Germany, Greece and Italy) have insight in the Apparent Motion of the Sun and Stars. The systematic design of the AMoSS test instrument allowed us to detect differences in understanding of the apparent motion of the Sun and stars. We administered the test with 12 multiple choice questions to 13-17 years old students of 5 European secondary schools (N=348) during a science lesson in school. We also asked them to explain their choices. We found similar results in the four countries: most students only demonstrate a rudimentary understanding of the apparent motion of the Sun and stars for different times during the day, different times during the year and different locations of the observer on Earth. Moreover, we see a clear distinction between the responses to the Sun-related and the star-related questions. In general, the questions about the Sun are answered more correctly than the questions about the stars. By using one classification system for the four countries we were able to compare written explanations in different languages. In combination with a latent class analysis, we identified different mental models that students use to answer questions about the apparent motion of the Sun and stars.

In high school geography students are taught about complex geospatial relations that often focus on the interaction between humans and their environment. Systems thinking as an approach concentrates in general on understanding interconnections between variables in a system to see the bigger picture. Therefore systems thinking is an appropriate approach in geography education. Recently it is also seen as an important cognitive skill in some European countries. However, an appropriate tool to assess systems thinking in geography is currently missing. In this article, a test and its development are described. The test was administered with 617 students of 16 to 18 years old in secondary education in Flanders. Based on the validation process, the reliability measures and the distribution of the students’ scores, it is concluded that the proposed test is a valid and reliable assessment instrument for future research.

We investigated to what extent secondary school students have insight in the apparent motion of the Sun and stars (AMoSS). We used the AMoSS test instrument, which focuses on distinctions between different aspects of the apparent motion of the Sun and stars. It consists of 12 multiple-choice questions accompanied by explanations. We administered the test to students of the fifth year (16???17 years old) of six Belgian secondary schools (N 1/4 410) during a science lesson in school and asked them to explain their choices. We found that, despite instruction, most students only demonstrate a rudimentary understanding of the apparent motion of the Sun and stars for different times during the day, different times during the year, and different locations of the observer. Moreover, we see a clear distinction between the responses to the questions about the Sun and stars. Thanks to the classification system that we developed to categorize the written explanations and a latent class analysis, we are able to identify different mental models that students use to answer questions about the apparent motion of the Sun and stars.

Young children, students, and adults may have alternative ideas about the motion of the Sun and stars as we observe them in the sky. However, a good understanding of this apparent motion is essential as a starting point to study more advanced astronomical concepts, especially when these include astronomical observations. In this paper, we describe the development and validation of the apparent motion of Sun and stars (AMoSS) test, which can measure to what extent students have insight into the apparent motion of the Sun and stars. We propose a framework that allows one to compare students' understanding of the specific aspects of these apparent motions in relation to the time of the day, time of the year, and the observer's latitude. For each of these aspects, we designed test items for both the Sun and the symmetric apparent motion aspect of the stars. The reliability and validity of the test are established by analyzing answers of both secondary school and university students and by presenting the questions to a panel of experts. We report on the design and validation process and present the final version of the test.

Several challenges faced by humanity, such as the world food problem, migration flows or climate change, are all taught about in geography courses worldwide. Behind these challenges are complex systems consisting of several interrelated causes and consequences. In order to better understand these highly complex geographical systems, a systems thinking approach is helpful. However, the spatial embeddedness of relations in a system is often not included in this approach. Although this spatial embeddedness is important to understand geographical systems, it also contributes to the complexity of systems. The aim of this study is to examine whether the enrichment of causal diagrams with spatial scales helps students to better understand these systems. A quasi experimental design with an intervention of four lessons and task-based think-aloud interviews is used. These results show that students who have used these enriched diagrams in class are more aware of the spatial embeddedness of relations and therefore achieve a higher level of geographical thinking. This study shows the potential of enriched causal diagrams to make them actively use this spatial component while processing information.

Increasing interconnectedness of people and goods enhances the complexity of geographical problems. For students to understand geography, systems thinking-and in this context, the use of causal diagrams-is a promising approach. A quasi-experimental design is used in which the systems thinking ability of students working with causal diagrams is compared to a control group where students did not work with causal diagrams. Pre- and posttests were taken by 448 students in the experimental group and 168 students in the control group. The results indicate that students in the experimental group outperform students in the control group.

The use of causal diagrams to externalize the mental representation of a problem is recognized to be an important step in solving complex problems.In geography education several global challenges taught about in class are highly complex due to the interconnectedness of many causes and consequences.A systems thinking approach might be helpful to better understand these global challenges.Former studies have shown the effectiveness of concept maps and causal diagrams to foster students' systems thinking.However, it is not always obvious for students to construct proper causal diagrams.In order to optimize teaching strategies concerning these complex systems in geography education, this study analyzes students' cognitive strategies while constructing a causal diagram.We used task-based thinkaloud interviews to study their cognitive strategies.Four different cognitive strategies were observed.The different types of cognitive strategies all resulted in an acceptable constructed causal diagram by the students.The presented insights are explorative, but it reveals the thinking processes that are mostly tacit and therefore has the potential to contribute to better teaching strategies.After all, if we know what processes novices go through while carrying out a complex skill, which are often taken for granted by experts, in this case geography teachers, we can raise awareness among teachers to Theoretical Background Research on Complex Problem SolvingComplex global challenges or problems such as climate change, hunger and migration flows are studied in geography.These problems can be considered to be complex ill-structured problems.Jonassen (2004) identifies four ways in which problems can vary: structuredness, domain specificity, complexity, and dynamicity.Solutions to ill-structured problems are not predictable, the procedure to solve the problem is often not known and concepts and principles from different domains are required to solve the problems.Furthermore, these problems are also highly complex and dynamic, due to the amount of involved interconnected variables and the fact that these variables, and thereby the problem as a whole, change over time (Jonassen, 2004).According to these criteria the problems mentioned above are ill-structured problems, also known as wicked problems.Complex problems require different intellectual skills and cognitive operations to deal with than well-structured problems (Funke, 2010;Shin, Jonassen, & McGee, 2003), and therefore teaching strategies should be different (Jonassen, 2004).Several authors describe cognitive strategies involved in complex problem solving.Weinstein and Mayer (1986), for instance, mentioned selecting important information in texts, relating content to already acquired knowledge, structuring the learning content in summaries and schemas, critically processing the content by forming an opinion about explicitly take those processes into account while designing lessons.

With further down-scaling below 0.25mum technologies, CoSi2 is replacing TiSi2 because of its superior formation chemistry on narrow lines and favourable stress behaviour. Shallow trench isolation (STI) is used as the isolation technique in these technologies. In this study, convergent beam electron diffraction (CBED) measurements and finite element modelling (FEM) are performed to evaluate the local stress components in the silicon substrate, induced in STI structures with a 45 nm or a 85 nm CoSi2 silicidation. High compressive stresses in the active area and tensile stress around the trench corners are observed.

It is well-known that misconceptions exist on a range of topics. The origin of these misconceptions can be very different, but some of them can be understood by students struggling with the application of physics concepts in real life situations or in the context of another school subject, e.g. geography. In this paper, different strategies to tackle misconceptions concerning the formation of clouds and wind were studied. In Flanders, this topic is studied in geography at the end of secondary education, but underlying physics principles are taught in the preceding physics courses in the middle of secondary school. Three different strategies to teach the topic in geography were designed and compared: a traditional, teacher centered lecture, a lecture including an experiment showing the process of cloud and wind formation and a lecture in which the students worked through the material themselves by means of an interactive learning path on a tablet pc and in which the experiment was included in a movie. In all lectures, explicit reference was made to the underlying physical concepts. In a pretest-posttest quasi-experimental design, the impact of the three formats on the student s’ conceptual understanding was studied. Results show that the learning outcomes of students in the tablet pc class are not as good as those in the other two conditions. Teaching method, but also learning material and attitude of students, can explain these differences.

An Steegen reveals some of the secrets of semiconductor scaling - a pipeline full of materials, device architectures and advanced techniques that promise to further extend semiconductor scaling.

An increasing interconnectedness of people and goods enhances the complexity of many geographical problems. For students to understand geography, systems thinking is a promising approach. It helps to understand increasing complexity by looking at the entire system and at the interconnectedness between the elements in the system. Encouraging students to use tools to handle complexity may help them to understand that complexity. Despite the advantages claimed by the proponents of systems thinking, the implementation into education has not been spread widely (Plate, 2010). Similarly, research on how to foster systems thinking in secondary education in general and in geography education in particular is limited (Assaraf & Orion, 2005). Previous research demonstrates improving learning outcomes in science education via computer-based modelling (Smetana & Bell, 2012) and conceptual representations (Hmelo-Silver, Jordan, Eberbach, & Sinha, 2016). However this research is rather limited in geography education in which space and timescales have to be taken into account. The overall aim of the study is therefore to better understand how systems thinking ability of students in a geography course can be fostered. The following research questions are guiding the research: What is the effect of the use of causal diagrams in geography lessons on the ability to systems thinking of students in upper secondary education? Is this effect different according to their study program, grade or gender? A quasi-experimental research design in the form of a classroom intervention was used. In total twelve teachers of eleven different schools implemented a lesson series, developed in consultation between the researcher and these teachers. The students in the experimental group (n=552) were trained to retrieve information (e.g. determining variables) from all kinds of sources and combine them into causal diagrams which visualize the relations between these variables in the system. The construction (and accompanying discussion) of these diagrams was crucial in grasping the problems as a whole. Furthermore, students used these diagrams to examine the effect of certain interventions into the systems. The interpretation of the data from a geographical, and thus multidimensional perspective in which complexity is fully recognized, is at the core of the inquiry-based instruction aiming to foster systems thinking. The students in the control group (n= 195) learned the same content without the use of these causal diagrams. Both student groups took a pretest and posttest to measure their systems thinking ability. Content validation of both tests was performed by expert panels, while the reliability was statistically analyzed. Quantitative results from the tests show a positive impact of the intervention. The experimental group has a significantly higher mean score on the posttest. Qualitative observations ∗Speaker †Corresponding author: marjolein.cox@kuleuven.be sciencesconf.org:eugeo2017:150626 do reveal a deeper reasoning by students while constructing a causal diagram. However, the processing of the information in the texts, graphs and maps in order to select variables and to understand the connections in the systems is rather difficult for certain students. Differences in study program have an impact on their systems thinking ability. Particularly in study programs with a higher success rate in higher education a higher ability to create causal diagrams was observed in the pretest. Despite these positive effects observed in the intervention, some concern has risen about the attention students have for spatial patterns and spatial embeddedness of the variables. Indeed, students seem not to be aware of the fact that some variables on one place cause an effect in a different place, nor that this effect is on a global or a local level. In short, students do not realize that every variable has its own spatial pattern. In future research, more attention should be paid at embedding a spatial and temporal component in the study of the variables. Assaraf, O. B. Z., & Orion, N. (2005). Development of system thinking skills in the context of earth system education. Journal of Research in Science Teaching, 42 (5), 518–560. doi:10.1002/tea.20061 Hmelo-Silver, C. E., Jordan, R., Eberbach, C., & Sinha, S. (2016). Systems learning with a conceptual representation: a quasi-experimental study. Instructional Science. doi:10.1007/s11251016-9392-y Plate, R. (2010). Assessing individuals understanding of nonlinear causal structures in complex systems. System Dynamics Review, 26 (1), 19–33. doi:10.1002/sdr.432 Smetana, L. K., & Bell, R. L. (2012). Computer Simulations to Support Science Instruction and Learning: A critical review of the literature. International Journal of Science Education, 34 (9), 1337–1370. doi:10.1080/09500693.2011.605182

ABSTRACT An increasing interconnectedness of people and goods enhances the complexity of many geographical problems. For students to understand geography, systems thinking is a promising approach. It helps to understand increasing complexity by looking at the entire system and at the interconnectedness between the elements in the system. In order to develop adequate systems oriented teaching and learning the current state of the art of students’ systems thinking ability needs to be better understood. The authors developed a measuring tool in the form of a paper-and-pencil test in which 735 students in the last or penultimate year of secondary school (age 16–18 year) in Flanders, Belgium, took part. The main findings reveal a rather poor general level of students’ systems thinking ability. Students have many difficulties recognizing relationships between variables when several elements of systems thinking come together such as in feedback loops, interactions between human and physical environment, and a combination of different information sources. Rather great differences were found according to the students’ study background as well as an interaction effect between grade and gender of the students.

By optimizing design rules, layout, devices and parasitics, we show how 5 Tracks standard cells with one fin can be enabled. This reduces area by 16% without pitch scaling and provides 34% energy gain from 6T cells. The loss in speed of 15% can be recovered by different front-end solutions. Air gap spacers are the most efficient booster and provide an extra 16% gain in energy. Lateral Nanowires can compete in speed with FinFETs with an extra energy gain of 12% if tight vertical pitch of 10 nm between wires can be achieved.