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Evaluating Inflectional Complexity Crosslinguistically: a Processing Perspective
No full textThe paper provides a cognitively motivated method for evaluating the inflectional complexity of a language, based on a sample of "raw" inflected word forms processed and learned by a recurrent self-organising neural network with fixed parameter setting. Training items contain no information about either morphological content or structure. This makes the proposed method independent of both meta-linguistic issues (e.g. format and expressive power of descriptive rules, manual or automated segmentation of input forms, number of inflectional classes etc.) and language-specific typological aspects (e.g. word-based, stem-based or template-based morphology). Results are illustrated by contrasting Arabic, English, German, Greek, Italian and Spanish
From long-term ecosystem monitoring to regional modelling of ecosystem function in the National Park Kalkalpen, Austria
No full textHere we show the usefulness of Long-Term Ecosystem Research (LTER) for scrutinizing climate change impacts on forest carbon (C) sequestration in the National Park Kalkalpen, Austria. Climate change will accelerate forest disturbances causing a decrease in forest C sink strength in the future. Delayed forest regeneration after stand replacing disturbances due to ungulate browsing opens an additional window for enhanced C loss. However, the dense grass layer, developing after large-scale disturbances, reduces ecosystem C loss by half, causing less climate feedback than expected. By applying two ecosystem models, we could show that wind and spruce bark beetle disturbances, which occurred during the last two decades throughout the National Park, increased soil organic C decomposition by 20% and will, together with future climate change, cause a 4% drop in forest ecosystem C stock by the year 2200
Ecosystem Services and Pressures in European Protected Areas: Divergent Views of Environmental Scientists and Managers
No full textIn the last decades intense anthropogenic pressure caused serious threats to ecosystems, leading to degradation of habitats and environmental quality, thereby increasing the risk of loss of ecosystem services (ES). Protected Areas (PA) may help to counterbalance degradation and associated loss of ES. In the EcoPotential project the state-of-art view was surveyed among environmental scientists and managers of PAs regarding the importance of various ecological, environmental, and socio-economic indicators for ES and pressures in their PA. Therefore, eight European PAs in mountainous areas, e.g. Kalkalpen and Gran Paradiso, and for comparison a few coastal PAs, e.g. Wadden Sea, were selected. Environmental scientists predominantly indicated abiotic and biotic factors as being most important for ES and pressures, whereas managers proportionally indicated socio-economic and cultural factors more often. Therefore, socio-economic and cultural factors (emphasised by managers) and abiotic and biotic factors (emphasised by scientists) need to be more integrated. Methods used worldwide for assessing the effectiveness of management in PAs may inspire the design of such an integrated framework. Moreover, in order to come to a concise list of variables for use in stakeholder engagement (incl. managers and policy-makers) these variables should be harmonised and preferably easy to measure, e.g. through Remote Sensing (RS). In our presentation we will show the different views of managers and scientists, how we may harmonise variables, and examples on how social (aesthetic) ES may be measured by RS
Advancing marine biological observations and data requirements of the complementary essential ocean variables (EOVs) and essential biodiversity variables (EBVs) frameworks
No full textMeasurements of the status and trends of key indicators for the ocean and marine life are required to inform policy and management in the context of growing human uses of marine resources, coastal development, and climate change. Two synergistic efforts identify specific priority variables for monitoring: Essential Ocean Variables (EOVs) through the Global Ocean Observing System (GOOS), and Essential Biodiversity Variables (EBVs) from the Group on Earth Observations Biodiversity Observation Network (GEO BON) (see Data Sheet 1 in Supplementary Materials for a glossary of acronyms). Both systems support reporting against internationally agreed conventions and treaties. GOOS, established under the auspices of the Intergovernmental Oceanographic Commission (IOC), plays a leading role in coordinating global monitoring of the ocean and in the definition of EOVs. GEO BON is a global biodiversity observation network that coordinates observations to enhance management of the world\u27s biodiversity and promote both the awareness and accounting of ecosystem services. Convergence and agreement between these two efforts are required to streamline existing and new marine observation programs to advance scientific knowledge effectively and to support the sustainable use and management of ocean spaces and resources. In this context, the Marine Biodiversity Observation Network (MBON), a thematic component of GEO BON, is collaborating with GOOS, the Ocean Biogeographic Information System (OBIS), and the Integrated Marine Biosphere Research (IMBeR) project to ensure that EBVs and EOVs are complementary, representing alternative uses of a common set of scientific measurements. This work is informed by the Joint Technical Commission for Oceanography and Marine Meteorology (JCOMM), an intergovernmental body of technical experts that helps international coordination on best practices for observing, data management and services, combined with capacity development expertise. Characterizing biodiversity and understanding its drivers will require incorporation of observations from traditional and molecular taxonomy, animal tagging and tracking efforts, ocean biogeochemistry, and ocean observatory initiatives including the deep ocean and seafloor. The partnership between large-scale ocean observing and product distribution initiatives (MBON, OBIS, JCOMM, and GOOS) is an expedited, effective way to support international policy-level assessments (e.g., the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services or IPBES), along with the implementation of international development goals (e.g., the United Nations Sustainable Development Goals)
Optimal spatiotemporal effort allocation for invasive species removal incorporating a removal handling time and budget
No full textImproving strategies for the control and eradication of invasive species is an important aspect of nature conservation, an aspect where mathematical modeling and optimization play an important role. In this paper, we introduce a reaction?diffusion partial differential equation to model the spatiotemporal dynamics of an invasive species, and we use optimal control theory to solve for optimal management, while implementing a budget constraint. We perform an analytical study of the model properties, including the well?posedness of the problem. We apply this to two hypothetical but realistic problems involving plant and animal invasive species. This allows us to determine the optimal space and time allocation of the efforts, as well as the final length of the removal program so as to reach the local extinction of the species
Is inflectional irregularity dysfunctional to human processing?
No full textRegularly inflected verb forms are classically associated with the formal transparency and predictability of their internal constituents [ 1 , 2 , 3 ]. Transparency ensures that full forms can be segmented uniquely into their internal constituents: as in walk-s/walk-ed. Predictability allows for a speaker to fill in an empty paradigm cell, using information from other known forms of the same lexical paradigm and its inflection macro-class. From this perspective, irregulars appear to be dysfunctional to the human processing system, as they make it hard to infer - say - bought from buy , or segment bought appropriately into its constituent parts. Likewise, an influential psycholinguistic tradition relegates irregulars to the lexical store, whereas regulars are segmented by rules into their simpler constituents [ 4 , 5 ]. Here, we offer a few reasons for questioning this view. First, transparency and predictability are not dichotomous notions. Secondly, their influence on processing is not unidirectional. Unpredictable stems in irregularly inflected forms of complex inflectional systems provide a lot of processing information, by dynamically constraining the number of possible alternative endings during serial processing. Thirdly, acquisition of word inflection does not consist in associating co-occurring cues and outcomes, but in discriminating between multiple cues that are constantly in competition for their predictive value for a given outcome. We present the results of a few computer simulations with Self-organising Recurrent Neural Networks (TSOMs, [ 8 , 9 ]) that learn how to inflect high-frequency verb paradigms in 6 languages: English, German, Italian, Modern Greek, Modern Standard Arabic and Spanish. After training, each TSOM was tested on a word recognition (serial recoding) and a word production (serial recall) task, and results were analysed with generalised regression models. Processing uncertainty is differently apportioned on regulars and irregulars, depending on the nature of the processing task. While irregulars are harder to produce when they are unknown because they typically have fewer neighbours than regulars have, they are readily accessed once they are acquired, for exactly the same reason. Our data are in line with psycholinguistic evidence [ 10 , 11 ] that lexical processing is paced by two types of uniqueness point: Marslen-Wilson\u27s Uniqueness Point (UP), distinguishing unrelated onset-overlapping words [ 12 ], and the Complex Uniqueness Point (CUP), distinguishing paradigmatically-related words [ 11 ]. Late UPs are inhibitory and elicit prolonged reaction times in acoustic word recognition, explaining an early delay in word recognition of irregular stems. Similarly, late CUPs are inhibitory, and this accounts for a slowdown in the processing advantage of regulars, compared to irregulars, after UP. These structural factors interact in a variety of ways and concurrently affect human processing, to show that irregularly-inflected forms may in fact reflect communicative and processing constraints of the word processor. They provide strong evidence against a processing architecture that assumes compartmentalized, independent processing routes for some specific combinations of these factors (e.g. a rule-based route for a combination of transparency and predictability, and a memory-based route for all other combinations). In addition, they seem incompatible with Bayesian approaches to auditory word comprehension ignoring a word\u27s internal structure [ 13 ]. We suggest that a different design of the human language processor, based on a computational architecture integrating memory and processing as two different dynamics of the same underlying mechanism, can shed light on the complexity of inflection, and vindicate the role of irregular inflection in the system
Deep Learning of Inflection and the Cell-Filling Problem
No full textMachine learning offers two basic strategies for morphology induction: lexical segmentation and surface word relation. The first approach assumes that words can be segmented into morphemes. Inferring a novel inflected form requires identification of morphemic constituents and a strategy for their recombination. The second approach dispenses with segmentation: lexical representations form part of a network of associatively related inflected forms. Production of a novel form consists in filling in one empty node in the network. Here, we present the results of a task of word inflection by a recurrent LSTM network that learns to fill in paradigm cells of incomplete verb paradigms. Although the task does not require morpheme segmentation, we show that accuracy in carrying out the inflection task is a function of the model\u27s sensitivity to paradigm distribution and morphological structure
Microbiomes of gall-inducing copepod crustaceans from the corals Stylophora pistillata (Scleractinia) and Gorgonia ventalina (Alcyonacea)
No full textCorals harbor complex and diverse microbial communities that strongly impact host fitness and resistance to diseases, but these microbes themselves can be influenced by stresses, like those caused by the presence of macroscopic symbionts. In addition to directly influencing the host, symbionts may transmit pathogenic microbial communities. We analyzed two coral gall-forming copepod systems by using 16S rRNA gene metagenomic sequencing: (1) the sea fan Gorgonia ventalina with copepods of the genus Sphaerippe from the Caribbean and (2) the scleractinian coral Stylophora pistillata with copepods of the genus Spaniomolgus from the Saudi Arabian part of the Red Sea. We show that bacterial communities in these two systems were substantially different with Actinobacteria, Alphaproteobacteria, and Betaproteobacteria more prevalent in samples from Gorgonia ventalina, and Gammaproteobacteria in Stylophora pistillata. In Stylophora pistillata, normal coral microbiomes were enriched with the common coral symbiont Endozoicomonas and some unclassified bacteria, while copepod and gall-tissue microbiomes were highly enriched with the family ME2 (Oceanospirillales) or Rhodobacteraceae. In Gorgonia ventalina, no bacterial group had significantly different prevalence in the normal coral tissues, copepods, and injured tissues. The total microbiome composition of polyps injured by copepods was different. Contrary to our expectations, the microbial community composition of the injured gall tissues was not directly affected by the microbiome of the gall-forming symbiont copepods
River networks as ecological corridors: A coherent ecohydrological perspective
No full textThis paper draws together several lines of argument to suggest that an ecohydrological framework, i.e. laboratory, field and theoretical approaches focused on hydrologic controls on biota, has contributed substantially to our understanding of the function of river networks as ecological corridors. Such function proves relevant to: the spatial ecology of species; population dynamics and biological invasions; the spread of waterborne disease. As examples, we describe metacommunity predictions of fish diversity patterns in the Mississippi-Missouri basin, geomorphic controls imposed by the fluvial landscape on elevational gradients of species\u27 richness, the zebra mussel invasion of the same Mississippi-Missouri river system, and the spread of proliferative kidney disease in salmonid fish. We conclude that spatial descriptions of ecological processes in the fluvial landscape, constrained by their specific hydrologic and ecological dynamics and by the ecosystem matrix for interactions, i.e. the directional dispersal embedded in fluvial and host/pathogen mobility networks, have already produced a remarkably broad range of significant results. Notable scientific and practical perspectives are thus open, in the authors\u27 view, to future developments in ecohydrologic research
Atti del Pastaria Festival. Ingredienti innovativi: loro valutazione e criticit? tecnologiche
No full textNot availableIngredienti innovativi o "novel food" vengono definiti dall\u27Unione Europea come nuovi alimenti che non erano stati utilizzati per quello scopo prima del maggio 1997 (Regolamento europeo (UE)2015/2283, 25 novembre 2015). Un ingrediente innovativo deve quindi rispettare prima di tutto il criterio della sicurezza alimentare, che si trova al centro di ogni decisione, deve rispettare le regolamentazioni vigenti, deve portare dei benefici ai consumatori e deve contribuire a ridurre l\u27impatto ambientale