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Abstract The reduced sea ice extent and duration in the Arctic releases the rocky shores from one of its key physical disturbances shaping the zonation and depth extension of seaweed assemblages. In order to determine the consequences of reduced disturbance by sea ice, we studied the changes in the functioning and structure of the kelp belt at Hansneset, Kongsfjorden, between 1996-1998 and 2012–2014 using ecological network analysis (ENA). For each time period, a kelp belt flow network was constructed for 2.5 m and 5 m water depths in summer (June–July). We conducted a data-guided uncertainty analyses to evaluate the strength of the difference observed in the ENA results. At 2.5 m, the total system throughput –indicating the size of the system-significantly increased between the two periods. The number of parallel pathways (relative redundancy), the number of interactions (flow diversity) and the number of indirect interactions (Indirect/Direct) in the system were as well significantly higher at 2.5 m and 5 m in 2012–2014 compared to 1996–1998. These changes were related to the persistent colonization of the shallow sublittoral by kelps, which led to a diversification of filter feeders and an increase in omnivorous species. At 5 m, however, the kelp biomass and production decreased most likely due to the reduction of the underwater light climate between 1996-1998 and 2012–2014. In contrast, the macrozoobenthic biomass increased with a higher contribution of opportunistic and carnivorous species between these two periods. The increased values of these total system indicators suggest a more complex and mature kelp belt ecosystem in 2012–2014 compared to 1996–1998 probably due to the reduction of physical disturbances by ice. A future warming of the Arctic Ocean might enhance sea urchins grazing activity of kelp production as herbivory already increased between both periods. In a context of fast changes on ecosystem level triggered by concurrent multiple stressors, management objectives in the Arctic should be based on holistic approaches such as ENA. To do this, consistent monitoring of relevant food web components for model construction and data-guided uncertainty should be put in place. Highlights • Consistent and integrated management measures in the Arctic are very scares. • Kelp belt systems have great potential to develop in a warming Arctic. • We compared 4 kelp belt models representing 1996–98 and 2012–14 at 2.5 and 5 m depth. • The kelp belt system became more mature and resilient against external perturbations. • Further holistic monitoring of the very fast changing ecosystem are urgently needed. [ABSTRACT FROM AUTHOR]

Abstract Ecological network analysis (ENA) is an efficient tool to conduct holistic evaluation of the functioning and structure of ecosystems. ENA results can be used to support management decisions, but further development is needed to improve ENA application. We compared the food web functioning of three areas of the Wadden Sea: the Sylt-Rømø Bight, the Norderaue tidal basin and the Jade Bay, and present an example application of ENA indices in decision making processes. We used a sequential increase in uniform uncertainty from 50% to 99% using 10% increments to evaluate the robustness of the network comparisons. The results showed that the Jade Bay differed in its system functioning from the Sylt-Rømø Bight and the Norderaue tidal basin which represent the Northern Wadden Sea. The Jade Bay system, which is dominated by mudflats, had a heavier reliance on detritivory pathways, while the Northern Wadden Sea, which is dominated by Arenicola -sand flats, relied more on exchanges with the North Sea. Higher recycling, redundant pathways and flow diversity in the Jade Bay indicated that this system is probably more resilient against external perturbations than the Northern Wadden Sea systems which are more organized and specialized. This was related to the high standing stocks of suspension feeders in the Northern Wadden Sea, resulting from the establishment of several invasive suspension feeders, such as the Pacific oysters, the American razor clams and the common slipper shell. This study showed that 1- uncertainty analyses are crucial for the interpretation of ENA results and their use in management, 2- temporal measurable trends of indices which are robust to model uncertainty would be more appropriate for decision making than single reference values, 3- using ENA for assessment purposes in the Wadden Sea must be based on several representative sites taking into account their habitat types as well as morphological and physical characteristics, in terms of water depth, hydrodynamics and degree of enclosure of back barrier areas. Highlights • Ecological Network Analysis (ENA) can be used to inform management decisions. • We compare ENA results of three Wadden Sea systems as an example of ENA application. • The Jade Bay, dominated by mudflat, is more resilient than the Northern Wadden Sea. • Uncertainty analyses are crucial to use ENA results in decision making. • The choice of monitored sites for management should be based on main habitat type. [ABSTRACT FROM AUTHOR]

The wide range of immunosuppressive therapies and protocols permits tailored planning of the initial regimen according to the immunological risk status of individual patients. Pre-transplant risk assessment can include many factors, but there is no clear consensus on which parameters to take into account, and their relative importance. In general younger patients are known to be at higher risk for acute rejection, compounded by higher rates of non-adherence in adolescents. Donor age and recipient gender do not appear to exert a meaningful effect on risk of rejection per se , but black recipient ethnicity remains a well-established risk factor even under modern immunosuppression regimens. Little difference in risk is now observed between deceased- and living-donor recipients. Immunological risk assessment has developed substantially in recent years. Cross-match testing with cytotoxic analysis has long been supplemented by flow cytometry, but development of solid-phase single-bead antigen testing of solubilized human leukocyte antigens (HLA) to detect donor-specific antibodies (DSA) permits a far more nuanced stratification of immunological risk status, including the different classes and intensities of HLA antibodies Class I and/or II, including HLA-DSA. Immunologic risk evaluation is now often based on a combination of these tests, but other assessments are becoming more widely introduced, such as measurement of non-HLA antibodies against angiotensin type 1 (AT1) receptors or T-cell ELISPOT assay of alloantigen-specific donor. Targeted densensitization protocols can improve immunological risk, notably for DSA-positive patients with negative cytotoxicity and flow cross-match. HLA mismatch remains an important and undisputed risk factor for rejection. Delayed graft function also increases the risk of subsequent acute rejection, and the early regimen can be modified in such cases. Overall, there is a shift towards planning the immunosuppressive regimen based on pre-transplant immunology testing although certain conventional risk factors retain their importance. [ABSTRACT FROM AUTHOR]