2,000 research outputs found

    Environmental conditions of a salt-marsh biodiversity experiment on the island of Spiekeroog (Germany)

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    Field experiments investigating biodiversity and ecosystem functioning require the observation of abiotic parameters, especially when carried out in the intertidal zone. An experiment for biodiversity–ecosystem functioning was set up in the intertidal zone of the back-barrier salt marsh of Spiekeroog Island in the German Bight. Here, we report the accompanying instrumentation, maintenance, data acquisition, data handling and data quality control as well as monitoring results observed over a continuous period from September 2014 to April 2017. Time series of abiotic conditions were measured at several sites in the vicinity of newly built experimental salt-marsh islands on the tidal flat. Meteorological measurements were conducted from a weather station (WS, https://doi.org/10.1594/PANGAEA.870988), oceanographic conditions were sampled through a bottom-mounted recording current meter (RCM, https://doi.org/10.1594/PANGAEA.877265) and a bottom-mounted tide and wave recorder (TWR, https://doi.org/10.1594/PANGAEA.877258). Tide data are essential in calculating flooding duration and flooding frequency with respect to different salt-marsh elevation zones. Data loggers (DL) for measuring the water level (DL-W, https://doi.org/10.1594/PANGAEA.877267), temperature (DL-T, https://doi.org/10.1594/PANGAEA.877257), light intensity (DL-L, https://doi.org/10.1594/PANGAEA.877256) and conductivity (DL-C, https://doi.org/10.1594/PANGAEA.877266) were deployed at different elevational zones on the experimental islands and the investigated salt-marsh plots. A data availability of 80% for 17 out of 23 sensors was achieved. Results showed the influence of seasonal and tidal dynamics on the experimental islands. Nearby salt-marsh plots exhibited some differences, e.g., in temperature dynamics. Thus, a consistent, multi-parameter, long-term dataset is available as a basis for further biodiversity and ecosystem functioning studies

    A Systematic Review of Sodium Intake and its Impact on Cardiovascular Health: Insights from Costa Rican Studies

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    Cardiovascular disease (CVD) is a leading cause of morbidity and mortality worldwide, with dietary sodium intake identified as a critical risk factor. This systematic review comprehensively examines the existing literature on sodium intake and its impact on cardiovascular health in Costa Rica. Fifteen relevant studies were analyzed, revealing concerning patterns of sodium consumption, particularly among youngsters and adolescents, with processed and fast foods being major contributors. High sodium intake was consistently associated with elevated blood pressure, a well-established CVD risk factor. The review also assessed sodium reduction initiatives and strategies, demonstrating the potential benefits of interventions in reducing cardiovascular risk. Challenges in addressing sodium consumption in Costa Rica include promoting healthier dietary habits from a young age, collaborating with the food industry for stricter regulations, and addressing socioeconomic disparities in healthcare access. The review highlights the need for evidence-based interventions and policies to reduce the burden of CVD in Costa Rica. Future research should explore longitudinal trends in sodium intake and cardiovascular outcomes, conduct qualitative studies on perception and barriers to sodium reduction, and evaluate the long-term effectiveness of interventions. Implementing targeted public health campaigns and industry regulations can promote healthier eating behaviors and improve overall cardiovascular well-being in the population

    Draft Genome Sequences of Facultative Methylotrophs, Gemmobacter sp. Strain LW1 and Mesorhizobium sp. Strain 1M-11, Isolated from Movile Cave, Romania

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    Facultative methylotrophs belonging to the genera Gemmobacter and Mesorhizobium were isolated from microbial mat and cave water samples obtained from the Movile Cave ecosystem. Both bacteria can utilize methylated amines as their sole carbon and nitrogen source. Here, we report the draft genome sequences of Gemmobacter sp. strain LW1 and Mesorhizobium sp. strain IM1

    Cultivation and analysis of anthocyanin containing types of potatoes in organic farming regarding cultivability and additional health benefits

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    In a two year research project a representative spectrum of blue potato varieties were cultivated and tested in detail regarding disease infestation, yield potential and the influence of production systems (organic). Cultivation recommendations for blue potatoes could be deduced from this. Furthermore the varying anthocyanin content as well as the antioxidant capacity of the varieties used was analysed. Varieties with a particularly high content will undergo further tests to show the influence of the manner of preparation (boiling, steaming, frying) and determine their use for the processing industry. The combination of ecologically produced potatoes with „additional health benefits“ arouses the customers interest. The cultivation of high yield blue types can be an alternative to the cultivation of yellow fleshed high yield varieties in organic operating companies

    Changes in MEG resting-state networks are related to cognitive decline in type 1 diabetes mellitus patients

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    OBJECTIVE: Integrity of resting-state functional brain networks (RSNs) is important for proper cognitive functioning. In type 1 diabetes mellitus (T1DM) cognitive decrements are commonly observed, possibly due to alterations in RSNs, which may vary according to microvascular complication status. Thus, we tested the hypothesis that functional connectivity in RSNs differs according to clinical status and correlates with cognition in T1DM patients, using an unbiased approach with high spatio-temporal resolution functional network.; METHODS: Resting-state magnetoencephalographic (MEG) data for T1DM patients with (n=42) and without (n=41) microvascular complications and 33 healthy participants were recorded. MEG time-series at source level were reconstructed using a recently developed atlas-based beamformer. Functional connectivity within classical frequency bands, estimated by the phase lag index (PLI), was calculated within eight commonly found RSNs. Neuropsychological tests were used to assess cognitive performance, and the relation with RSNs was evaluated.; RESULTS: Significant differences in terms of RSN functional connectivity between the three groups were observed in the lower alpha band, in the default-mode (DMN), executive control (ECN) and sensorimotor (SMN) RSNs. T1DM patients with microvascular complications showed the weakest functional connectivity in these networks relative to the other groups. For DMN, functional connectivity was higher in patients without microangiopathy relative to controls (all p<0.05). General cognitive performance for both patient groups was worse compared with healthy controls. Lower DMN alpha band functional connectivity correlated with poorer general cognitive ability in patients with microvascular complications.; DISCUSSION: Altered RSN functional connectivity was found in T1DM patients depending on clinical status. Lower DMN functional connectivity was related to poorer cognitive functioning. These results indicate that functional connectivity may play a key role in T1DM-related cognitive dysfunction

    On the k-Boundedness for Existential Rules

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    The chase is a fundamental tool for existential rules. Several chase variants are known, which differ on how they handle redundancies possibly caused by the introduction of nulls. Given a chase variant, the halting problem takes as input a set of existential rules and asks if this set of rules ensures the termination of the chase for any factbase. It is well-known that this problem is undecidable for all known chase variants. The related problem of boundedness asks if a given set of existential rules is bounded, i.e., whether there is a predefined upper bound on the number of (breadth-first) steps of the chase, independently from any factbase. This problem is already undecidable in the specific case of datalog rules. However, knowing that a set of rules is bounded for some chase variant does not help much in practice if the bound is unknown. Hence, in this paper, we investigate the decidability of the k-boundedness problem, which asks whether a given set of rules is bounded by an integer k. We prove that k-boundedness is decidable for three chase variants, namely the oblivious, semi-oblivious and restricted chase.Comment: 20 pages, revised version of the paper published at RuleML+RR 201

    The importance of phytoplankton trait variability in spring bloom formation

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    About 60 years ago, the critical depth hypothesis was proposed to describe the occurrence of spring phytoplankton blooms and emphasized the role of stratification for the timing of onset. Since then, several alternative hypotheses appeared focusing on the role of grazing and mixing processes such as turbulent convection or wind activity. Surprisingly, the role of community composition—and thus the distribution of phytoplankton traits—for bloom formation has not been addressed. Here, we discuss how trait variability between competing species might influence phytoplankton growth during the onset of the spring bloom. We hypothesize that the bloom will only occur if there are species with a combination of traits fitting to the environmental conditions at the respective location and time. The basic traits for formation of the typical spring bloom are high growth rates and photoadaptation to low light conditions, but other traits such as nutrient kinetics and grazing resistance might also be important. We present concise ideas on how to test our theoretical considerations experimentally. Furthermore, we suggest that future models of phytoplankton blooms should include both water column dynamics and variability of phytoplankton traits to make realistic projections instead of treating the phytoplankton bloom as an aggregate community phenomenon

    Diversity and community biomass depend on dispersal and disturbance in microalgal communities

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    The evidence for species diversity effects on ecosystem functions is mainly based on studies not explicitly addressing local or regional processes regulating coexistence or the importance of community structure in terms of species evenness. In experimental communities of marine benthic microalgae, we altered the successional stages and thus the strength of local species interactions by manipulating rates of dispersal and disturbance. The treatments altered realized species richness, evenness and community biomass. For species richness, dispersal mattered only at high disturbance rates; when opening new space, dispersal led to maximized richness at intermediate dispersal rates. Evenness, in contrast, decreased with dispersal at low or no disturbance, i.e. at late successional stages. Community biomass showed a nonlinear hump-shaped response to increasing dispersal at all disturbance levels.We found a positive correlation between richness and biomass at early succession, and a strong negative correlation between evenness and biomass at late succession. In early succession both community biomass and richness depend directly on dispersal from the regional pool, whereas the late successional pattern shows that if interactions allow the most productive species to become dominant, diverting resources from this species (i.e. higher evenness) reduces production. Our study emphasizes the difference in biodiversity–function relationships over time, as different mechanisms contribute to the regulation of richness and evenness in early and late successional stages

    Effects of site‐selection bias on estimates of biodiversity change

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    Estimates of biodiversity change are essential for the management and conservation of ecosystems. Accurate estimates rely on selecting representative sites, but monitoring often focuses on sites of special interest. How such site‐selection biases influence estimates of biodiversity change is largely unknown. Site‐selection bias potentially occurs across four major sources of biodiversity data, decreasing in likelihood from citizen science, museums, national park monitoring, and academic research. We defined site‐selection bias as a preference for sites that are either densely populated (i.e., abundance bias) or species rich (i.e., richness bias). We simulated biodiversity change in a virtual landscape and tracked the observed biodiversity at a sampled site. The site was selected either randomly or with a site‐selection bias. We used a simple spatially resolved, individual‐based model to predict the movement or dispersal of individuals in and out of the chosen sampling site. Site‐selection bias exaggerated estimates of biodiversity loss in sites selected with a bias by on average 300–400% compared with randomly selected sites. Based on our simulations, site‐selection bias resulted in positive trends being estimated as negative trends: richness increase was estimated as 0.1 in randomly selected sites, whereas sites selected with a bias showed a richness change of −0.1 to −0.2 on average. Thus, site‐selection bias may falsely indicate decreases in biodiversity. We varied sampling design and characteristics of the species and found that site‐selection biases were strongest in short time series, for small grains, organisms with low dispersal ability, large regional species pools, and strong spatial aggregation. Based on these findings, to minimize site‐selection bias, we recommend use of systematic site‐selection schemes; maximizing sampling area; calculating biodiversity measures cumulatively across plots; and use of biodiversity measures that are less sensitive to rare species, such as the effective number of species. Awareness of the potential impact of site‐selection bias is needed for biodiversity monitoring, the design of new studies on biodiversity change, and the interpretation of existing data

    Kartoffeln mit Zusatznutzen – Antioxidative Kapazität und Erträge ausgewählter blau- und rotfleischiger Kartoffelsorten im ökologischen und integrierten Landbau

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    In a three year research project a representative spectrum of coloured potato varieties were cultivated and tested in detail regarding yield potential and the influence of production systems (organic/integrated). The varying anthocyanin content as well as the antioxidant capacity of the types used were analysed to determine their potential health benefits. Types with a particularly high content undergo further tests to show the influence of the manner of preparation (boiling, steaming, frying) and determine their use for the processing industry. The cultivation of high yield blue types can be an alternative to the cultivation of yellow fleshed high yield types in organic or integrated operating farm companies
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