Nitrogen flows from European watersheds to coastal marine waters

Nitrogen flows from European watersheds to coastal marine waters Executive summary Nature of the problem • Most regional watersheds in Europe constitute managed human territories importing large amounts of new reactive nitrogen. • As a consequence, groundwater, surface freshwater and coastal seawater are undergoing severe nitrogen contamination and/or eutrophication problems. Approaches • A comprehensive evaluation of net anthropogenic inputs of reactive nitrogen (NANI) through atmospheric deposition, crop N fixation,fertiliser use and import of food and feed has been carried out for all European watersheds. A database on N, P and Si fluxes delivered at the basin outlets has been assembled. • A number of modelling approaches based on either statistical regression analysis or mechanistic description of the processes involved in nitrogen transfer and transformations have been developed for relating N inputs to watersheds to outputs into coastal marine ecosystems. Key findings/state of knowledge • Throughout Europe, NANI represents 3700 kgN/km2/yr (range, 0–8400 depending on the watershed), i.e. five times the background rate of natural N2 fixation. • A mean of approximately 78% of NANI does not reach the basin outlet, but instead is stored (in soils, sediments or ground water) or eliminated to the atmosphere as reactive N forms or as N2. • N delivery to the European marine coastal zone totals 810 kgN/km2/yr (range, 200–4000 depending on the watershed), about four times the natural background. In areas of limited availability of silica, these inputs cause harmful algal blooms. Major uncertainties/challenges • The exact dimension of anthropogenic N inputs to watersheds is still imperfectly known and requires pursuing monitoring programmes and data integration at the international level. • The exact nature of ‘retention’ processes, which potentially represent a major management lever for reducing N contamination of water resources, is still poorly understood. • Coastal marine eutrophication depends to a large degree on local morphological and hydrographic conditions as well as on estuarine processes, which are also imperfectly known. Recommendations • Better control and management of the nitrogen cascade at the watershed scale is required to reduce N contamination of ground- and surface water, as well as coastal eutrophication. • In spite of the potential of these management measures, there is no choice at the European scale but to reduce the primary inputs of reactive nitrogen to watersheds, through changes in agriculture, human diet and other N flows related to human activity

SeMA: A Design Methodology for Building Secure Android Apps

UX (user experience) designers visually capture the UX of an app via storyboards. This method is also used in Android app development to conceptualize and design apps. Recently, security has become an integral part of Android app UX because mobile apps are used to perform critical activities such as banking, communication, and health. Therefore, securing user information is imperative in mobile apps. In this context, storyboarding tools offer limited capabilities to capture and reason about security requirements of an app. Consequently, security cannot be baked into the app at design time. Hence, vulnerabilities stemming from design flaws can often occur in apps. To address this concern, in this paper, we propose a storyboard based design methodology to enable the specification and verification of security properties of an Android app at design time.Comment: Updates based on AMobile 2019 review

Revealing the Vicious Circle of Disengaged User Acceptance: A SaaS Provider's Perspective

User acceptance tests (UAT) are an integral part of many different software engineering methodologies. In this paper, we examine the influence of UATs on the relationship between users and Software-as-a-Service (SaaS) applications, which are continuously delivered rather than rolled out during a one-off signoff process. Based on an exploratory qualitative field study at a multinational SaaS provider in Denmark, we show that UATs often address the wrong problem in that positive user acceptance may actually indicate a negative user experience. Hence, SaaS providers should be careful not to rest on what we term disengaged user acceptance. Instead, we outline an approach that purposefully queries users for ambivalent emotions that evoke constructive criticism, in order to facilitate a discourse that favors the continuous innovation of a SaaS system. We discuss theoretical and practical implications of our approach for the study of user engagement in testing SaaS applications

Fields of Fuel: Market and Environmental Implications of Switching to Grass for U.S. Transport

Analyzes how increased commercial switchgrass production for biofuel affects land use, commodity prices, and the environment. Suggests policy actions on research, carbon impact estimates, mitigation payments, and air, soil, and water quality protection

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Human-computer interaction for development (HCI4D):the Southern African landscape

Human-Computer interaction for development (HCI4D) research aims to maximise the usability of interfaces for interacting with technologies designed specifically for under-served, under-resourced, and under-represented populations. In this paper we provide a snapshot of the Southern African HCI4D research against the background of the global HCI4D research landscape.We commenced with a systematic literature review of HCI4D (2010-2017) then surveyed Southern African researchers working in the area. The contribution is to highlight the context- specific themes and challenges that emerged from our investigation

Designing the Sakai Open Academic Environment: A distributed cognition account of the design of a large scale software system

Social accounts of technological change make the flexibility and openness of interpretations the starting point of an argument against technological determinism. They suggest that technological change unfolds in the semantic domain, but they focus on the social processes around the interpretations of new technologies, and do not address the conceptual processes of change in interpretations. The dissertation presents an empirically grounded case study of the design process of an open-source online software platform based on the framework of distributed cognition to argue that the cognitive perspective is needed for understanding innovation in software, because it allows us to describe the reflexive and expansive contribution of conceptual processes to new software and the significance of professional epistemic practices in framing the direction of innovation. The framework of distributed cognition brings the social and cognitive perspectives together on account of its understanding of conceptual processes as distributed over time, among people, and between humans and artifacts. The dissertation argues that an evolving open-source software landscape became translated into the open-ended local design space of a new software project in a process of infrastructural implosion, and the design space prompted participants to outline and pursue epistemic strategies of sense-making and learning about the contexts of use. The result was a process of conceptual modeling, which resulted in a conceptually novel user interface. Prototyping professional practices of user-centered design lent directionality to this conceptual process in terms of a focus on individual activities with the user interface. Social approaches to software design under the broad umbrella of human-centered computing have been seeking to inform the design on the basis of empirical contributions about a social context. The analysis has shown that empirical engagement with the contexts of use followed from conceptual modeling, and concern about real world contexts was aligned with the user-centered direction that design was taking. I also point out a social-technical gap in the design process in connection with the repeated performance challenges that the platform was facing, and describe the possibility of a social-technical imagination.Ph.D