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Het afgelopen decennium werden er wereldwijd alarmerend hoge sterftecijfers bij honingbijen geregistreerd. Deze trend is problematisch omdat de bij een cruciale rol speelt als bestuiver in natuurlijke en agrarische ecosystemen. Deze problematiek wordt veroorzaakt door verschillende stressoren met de varroamijt (Varroa destructor) als belangrijkste. Onafhankelijk van de oorzaak is het eindresultaat echter hetzelfde: het immuunsysteem begeeft het waardoor de bij en bij uitbreiding het bijenvolk sterft. Om dit fenomeen te kunnen begrijpen, is het belangrijk een grondige kennis te bezitten van hun immuunsysteem. Deze is namelijk verantwoordelijk voor de bescherming van bij en bijenvolk tegen deze verschillende stressoren. Ondanks het grote belang van de bij en het huidige hoge aantal wetenschappelijke publicaties over honingbijen, is er nog maar weinig onderzoek naar hun cellulaire immuniteit verricht. In dit artikel worden de obstakels van het hemocytenonderzoek beschreven, zoals traumatische collectiemethoden, gebrek aan standaardisatie en onvoorzichtige extrapolatie (van insecten en leeftijden). Als laatste wordt een beknopt overzicht gegeven van de vermoedelijke hemocytentypes en hun functies.&nbsp

Environmental concepts are performative in that they help create the environment they describe. This paper explores the performativity of the ecosystem services concept in the field of integrated water management in Flanders (northern Belgium). The data was collected from 23 in-depth interviews with professionals in the field, conducted in two rounds with a five-year interval and complemented with on-site observations of practices applying the concept. Results indicate that ecosystem services was only marginally performative on its own, and rather was seen as a ‘co-performative concept’ that – in conjunction with existing concepts – could accelerate the envisioned integration process through promoting initiatives, mobilising stakeholders, shaping orientation, creating win-win situations, and more. Yet, despite these aspirations, the concept has in general failed to perform as expected. Many perceived ecosystem services as an academic concept, too complex for practical application. Common strategies were either to adapt the concept to fit one’s professional context or to create a new practical context (a stakeholder workshop, for example) where the concept could function. The paper goes on to discuss the more general implications of the (pseudo-)malleability and context-dependence of the ecosystem services concept.

Background The normal hindfoot angle is estimated between 2° and 6° of valgus in the general population. These results are solely based on clinical findings and plain radiographs. The purpose of this study is to assess the hindfoot alignment using weightbear CT. Methods Forty-eight patients, mean age of 39.6±13.2 years, with clinical and radiological absence of hindfoot pathology were included. A weightbear CT was obtained and allowed to measure the anatomical tibia axis (TAx) and the hindfoot alignment (HA). The HA was firstly determined using the inferior point of the calcaneus (HA IC ). A density measurement of this area was subsequently performed to analyze if this point concurred with an increased ossification, indicating a higher load exposure. Secondly the HA was determined by dividing the calcaneus in the long axial view (HALA) and compared to the (HA IC ) to point out any possible differences attributed to the measurement method. Reliability was assessed using an intra class correlation coefficient (ICC). Results The mean HA IC equaled 0.79° of valgus±3.2 (ICC HA IC =0.73) with a mean TAx of 2.7° varus±2.1 (ICCTA=0.76). The HALA equaled 9.1° of valgus±4.8 (ICCHA LA=0.71) and differed significantly by a P IC , which showed a more neutral alignment. Correlation between both was shown to be good by a Spearman's correlation coefficient of 0.74. The mean density of the inferior calcaneal area equaled 271.3±84.1 and was significantly higher than the regional calcaneal area ( P Conclusions These results show a more neutral alignment of the hindfoot in this group of non-symptomatic feet as opposed to the generally accepted constitutional valgus. This could have repercussion on hindfoot position during fusion or in quantifying the correction of a malalignment. The inferior calcaneus point in this can be used during pre-operative planning of a hindfoot correction as an anatomical landmark due to its shown influence on load transfer.

Through a reflexive study, we performed a reality check of how Ecosystem Services valuation is performed compared to what could be referred to as a "theoretical ideal" of the BElgium Ecosystem Services (BEES) community of practice, reflecting the salient recent international literature on integrated valuation. By surveying the most recent case studies doing valuation, our results highlight that stakeholders are always included, a variety of values are generally accounted for using a diversity of methods, and increasingly transdisciplinary approaches. However, the main findings that (1) impacts on decision-making remain unclear, (2) real transdisciplinary studies, co-constructed by scientists and stakeholders are yet to be undertaken, and (3) sustainability issues (thresholds & fairness) are largely ignored, call for further research on how to conduct integrated and inclusive ES valuations. We argue that communities of practice such as BEES are appropriate arenas to foster such transdisciplinary studies, by facilitating the inclusion of a broad range of values and actors. We call for a broader review of best practices for ES integrated valuation, to identify factors of success, and guide further scientific research that aims at improving ES practice for decision-making. (C) 2018 Elsevier B.V. All rights reserved.

Arguments in the formulation, implementation and evaluation of biodiversity policy frame conservation in a range of ways and express interests that can be conflicting. Policy processes are cyclic and iterative by nature and as policies are constantly reformulated, argumentation has an important role at each policy stage. In this paper, we utilise the policy cycle model to shed light on biodiversity-related policy processes and the ways in which argumentation generates effects at different stages of these processes. The paper first draws on literature and the theory-driven assumptions are then illustrated with insights from four European case studies on different policy processes in which biodiversity conservation plays a role. The analysis shows that argumentation tends to evolve over the course of the policy cycle, and framing has a key role across the different policy stages. It is concluded that the ways in which arguments persist, accumulate, diffuse, and replace old arguments, should be the target of increased attention in policy analysis.

The prevention and management of invasive alien species (IAS) has become a high priority in European environmental policy. At the same time, ways of evaluating IAS continue to be a topic of lively debate. In particular, it is far from clear how directly policy makers’ value judgements are linked to the European (EU) policy against IAS. We examine the arguments used to support value judgements of both alien species and invasive alien species as well as the relation between these value judgements and the policy against IAS being developed at European level. Our study is based on 17 semi-structured interviews with experts from EU policy making and from the EU member states Austria, Belgium, Germany and Hungary. We found that our interviewees conceived of IAS in very different ways, expressed a variety of visions of biodiversity and ecosystem services, and adhered to widely different values expressed in their perceptions of IAS and the impacts of IAS. However, only some of these conceptualizations and value judgements are actually addressed in the rationale given in the preamble to the European IAS Regulation. Although value judgements about IAS differed, there was considerable agreement regarding the kind of action to be taken against them.

The number of collaborative initiatives between scientists and volunteers (i.e., citizen science) is increasing across many research fields. The promise of societal transformation together with scientific breakthroughs contributes to the current popularity of citizen science (CS) in the policy domain. We examined the transformative capacity of citizen science in particular learning through environmental CS as conservation tool. We reviewed the CS and social-learning literature and examined 14 conservation projects across Europe that involved collaborative CS. We also developed a template that can be used to explore learning arrangements (i.e., learning events and materials) in CS projects and to explain how the desired outcomes can be achieved through CS learning. We found that recent studies aiming to define CS for analytical purposes often fail to improve the conceptual clarity of CS; CS programs may have transformative potential, especially for the development of individual skills, but such transformation is not necessarily occurring at the organizational and institutional levels; empirical evidence on simple learning outcomes, but the assertion of transformative effects of CS learning is often based on assumptions rather than empirical observation; and it is unanimous that learning in CS is considered important, but in practice it often goes unreported or unevaluated. In conclusion, we point to the need for reliable and transparent measurement of transformative effects for democratization of knowledge production.