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Insects provide key pollination services in most terrestrial biomes, but this service depends on a multistep interaction between insect and plant. An insect needs to visit a flower, receive pollen from the anthers, move to another conspecific flower, and finally deposit the pollen on a receptive stigma. Each of these steps may be affected by climate change, and focusing on only one of them (e.g., flower visitation) may miss important signals of change in service provision. In this study, we combine data on visitation, pollen transport, and single-visit pollen deposition to estimate functional outcomes in the high Arctic plant-pollinator network of Zackenberg, Northeast Greenland, a model system for global warming-associated impacts in pollination services. Over two decades of rapid climate warming, we sampled the network repeatedly: in 1996, 1997, 2010, 2011, and 2016. Although the flowering plant and insect communities and their interactions varied substantially between years, as expected based on highly variable Arctic weather, there was no detectable directional change in either the structure of flower-visitor networks or estimated pollen deposition. For flower-visitor networks compiled over a single week, species phenologies caused major within-year variation in network structure despite consistency across years. Weekly networks for the middle of the flowering season emerged as especially important because most pollination service can be expected to be provided by these large, highly nested networks. Our findings suggest that pollination ecosystem service in the high Arctic is remarkably resilient. This resilience may reflect the plasticity of Arctic biota as an adaptation to extreme and unpredictable weather. However, most pollination service was contributed by relatively few fly taxa (Diptera: Spilogona sanctipauli and Drymeia segnis [Muscidae] and species of Rhamphomyia [Empididae]). If these key pollinators are negatively affected by climate change, network structure and the pollination service that depends on it would be seriously compromised.

When plant species compete for pollinators, climate warming may cause directional change in flowering overlap, thereby shifting the strength of pollinator‐mediated plant–plant interactions. Such shifts are likely accentuated in the rapidly warming Arctic. Targeting a plant community in Northeast Greenland, we asked (a) whether the relative phenology of plants is shifting with spatial variation in temperature, (b) whether local plants compete for pollination, and (c) whether shifts in climatic conditions are likely to affect this competition. We first searched for climatic imprints on relative species phenology along an elevational gradient. We then tested for signs of competition with increasing flower densities: reduced pollinator visits, reduced representation of plant species in pollen loads, and reduced seed production. Finally, we evaluated how climate change may affect this competition. Compared to a dominant species, Dryas integrifolia × octopetala, the relative timing of other species shifted along the environmental gradient, with Silene acaulis and Papaver radicatum flowering earlier toward higher elevation. This shift resulted in larger niche overlap, allowing for an increased potential for competition for pollination. Meanwhile, Dryas emerged as a superior competitor by attracting 97.2% of flower visits. Higher Dryas density resulted in reduced insect visits and less pollen of S. acaulis being carried by pollinators, causing reduced seed set by S. acaulis. Our results show that current variation in climate shifts the timing and flowering overlap between dominant and less‐competitive plant species. With climate warming, such shifts in phenology within trophic levels may ultimately affect interactions between them, changing the strength of competition among plants., For flowering species, it is not only important to be in temporal synchrony with the potential pollinators, but to also avoid the competition for pollination by other more attractive species. In the Arctic, changing climatic conditions change the relative flowering phenology of species, thus changing the overlap of their flowering and affecting the strength of the competition for pollination. Increasing overlap with dominant flowering species, Dryas integrifolia × octopetala, reduces flower visits, pollen transport, and seed set of Silene acaulis.

Publisher Copyright: © 2021 The Authors. Molecular Ecology Resources published by John Wiley & Sons Ltd. To associate specimens identified by molecular characters to other biological knowledge, we need reference sequences annotated by Linnaean taxonomy. In this study, we (1) report the creation of a comprehensive reference library of DNA barcodes for the arthropods of an entire country (Finland), (2) publish this library, and (3) deliver a new identification tool for insects and spiders, as based on this resource. The reference library contains mtDNA COI barcodes for 11,275 (43%) of 26,437 arthropod species known from Finland, including 10,811 (45%) of 23,956 insect species. To quantify the improvement in identification accuracy enabled by the current reference library, we ran 1000 Finnish insect and spider species through the Barcode of Life Data system (BOLD) identification engine. Of these, 91% were correctly assigned to a unique species when compared to the new reference library alone, 85% were correctly identified when compared to BOLD with the new material included, and 75% with the new material excluded. To capitalize on this resource, we used the new reference material to train a probabilistic taxonomic assignment tool, FinPROTAX, scoring high success. For the full-length barcode region, the accuracy of taxonomic assignments at the level of classes, orders, families, subfamilies, tribes, genera, and species reached 99.9%, 99.9%, 99.8%, 99.7%, 99.4%, 96.8%, and 88.5%, respectively. The FinBOL arthropod reference library and FinPROTAX are available through the Finnish Biodiversity Information Facility (www.laji.fi) at https://laji.fi/en/theme/protax. Overall, the FinBOL investment represents a massive capacity-transfer from the taxonomic community of Finland to all sectors of society.

Pollination is an ecosystem function of global importance. Yet, who visits the flower of specific plants, how the composition of these visitors varies in space and time and how such variation translates into pollination services are hard to establish. The use of DNA barcodes allows us to address ecological patterns involving thousands of taxa that are difficult to identify. To clarify the regional variation in the visitor community of a widespread flower resource, we compared the composition of the arthropod community visiting species in the genus Dryas (mountain avens, family Rosaceae), throughout Arctic and high-alpine areas. At each of 15 sites, we sampled Dryas visitors with 100 sticky flower mimics and identified specimens to Barcode Index Numbers (BINs) using a partial sequence of the mitochondrial COI gene. As a measure of ecosystem functioning, we quantified variation in the seed set of Dryas. To test for an association between phylogenetic and functional diversity, we characterized the structure of local visitor communities with both taxonomic and phylogenetic descriptors. In total, we detected 1,360 different BINs, dominated by Diptera and Hymenoptera. The richness of visitors at each site appeared to be driven by local temperature and precipitation. Phylogeographic structure seemed reflective of geological history and mirrored trans-Arctic patterns detected in plants. Seed set success varied widely among sites, with little variation attributable to pollinator species richness. This pattern suggests idiosyncratic associations, with function dominated by few and potentially different taxa at each site. Taken together, our findings illustrate the role of post-glacial history in the assembly of flower-visitor communities in the Arctic and offer insights for understanding how diversity translates into ecosystem functioning.

Traditional methods of managing concurrent processes are difficult and prone to errors. We propose that actions can provide a much simpler approach to the problem. In this paper, we use Temporal Logic of Actions to define an execution system that can be used to concurrently execute programs created with action languages. Important features of the system include naturally concurrent execution of actions, automated management of mutual exclusion, complete avoidance of low-level deadlocks, and implicit means of synchronization.

Global change is causing drastic changes in the pollinator communities of the Arctic. While arctic flowers are visited by a wide range of insects, flies in family Muscidae have been proposed as a pollinator group of particular importance. To understand the functional outcome of current changes in pollinator community composition, we examined the role of muscids in the pollination of a key plant species, the mountain avens ( Dryas ). We monitored the seed set of Dryas across 15 sites at Zackenberg, northeast Greenland, and used sticky flower mimics and DNA barcoding to describe the flower-visiting community at each site. To evaluate the consequences of shifts in pollinator phenology under climate change, we compared the flower visitors between the early and the late season. Our approach revealed a diverse community of insects visiting Dryas , including two-thirds of all insect species known from the area. Even against this diverse background, the abundance of muscid flies emerged as a key predictor for seed set in Dryas , whereas overall insect abundance and species richness had little or no effect. With muscid flies as the main drivers of the pollinating function in the High Arctic, a recently observed decline in their abundances offers cause for concern.

A data-driven approach to pinpointing the role of flower-visiting taxa.

This paper describes an online algorithm for detecting cow’s beat-to-beat interval on a small embedded microcontroller. The target device is an ECG implant which only provides limited calculation power and insufficient storage memory for long term complete ECG data logging. No common computationally efficient method for detecting the human R-wave was found successful for cattle ECG data with the used measurement configuration. Our algorithm detects a cow’s S-wave, which is the most distinguishable part of the QRS-complex. The offset and amplitude adaptive algorithm utilizes only arithmetic operations and logic conditions.

A complete list of taxa recorded at each site.

Appendix A. Further details on the experiments.

Designing a distributed system may force a choice between protocol stacks. This paper presents a method to employ stochastic Petri nets (SPNs) to compare stacks before any code gets written. The method is described by means of an example, choosing a transport protocol for the management of an access network. This is a heterogeneous network under the control of an operator between a customer and a broadband service of the operator. We would estimate the throughput and delay over a representative connection of the system using SPNs. In this, Erlang servers are employed to reduce the variance of delays and S-invariants to ensure model consistency

The proliferation of wireless LAN technologies and mobile terminals has prompted an increased need to support efficient and seamless roaming. Current mobility management protocols, such as the Mobile IP, as defined in RFC 2002, do not scale well into these requirements. Mobile IP employs mobility agents called home agent and foreign agent to support Internet-wide mobility. We present a distribution of the mobility agent functionalities into fully scalable, arbitrarily deep tree hierarchies of foreign agents. We show that by distributing part of the functionality of the home agent into the foreign network we increase the performance significantly and securely. Our performance measurements show that the reduction of network latency, due to signaling locality in the hierarchical mode, enables faster location update frequencies than in a RFC 2002-compliant non-hierarchical mode. In our solution, the Dynamics-HUT mobile IP version 0.6-pre4, we obtained an increase in the TCP stream cutoff location update frequency when using a hierarchical configuration. We also experienced similar increase when using fixed speed streamed UDP traffic with data speeds typical for some popular multimedia formats. Consequently, we claim that this kind of mobility agent architecture is suitable for scalable, fast-handoff networks where multimedia streaming is used.

The Mobile Ad-hoc Network (MANET) research aims at developing Internet routing protocols for networks of mobile nodes with limited resources. It has focused on discovering suitable basic routing algorithms in isolated, homogeneous MANET environments. Little emphasis has so far been given to practical usage scenarios and their implications to the MANET solutions.