Find research datasets worth reusing
Search datasets from major research repositories and use ShareScore to quickly assess how well each record supports discovery, access, and reuse.
6,569
datasets available to search
ShareScore release 0.9.0
Dataset results
6,569 results for “Long-term”
Data from: Unified pre- and postsynaptic long-term plasticity enables reliable and flexible learning
Although it is well known that long-term synaptic plasticity can be expressed both pre- and postsynaptically, the functional consequences of this arrangement have remained elusive. We show that spike-timing-dependent plasticity with both pre- and postsynaptic expression develops receptive fields with reduced variability and improved discriminability compared to postsynaptic plasticity alone. These long-term modifications in receptive field statistics match recent sensory perception experiments. Moreover, learning with this form of plasticity leaves a hidden postsynaptic memory trace that enables fast relearning of previously stored information, providing a cellular substrate for memory savings. Our results reveal essential roles for presynaptic plasticity that are missed when only postsynaptic expression of long-term plasticity is considered, and suggest an experience-dependent distribution of pre- and postsynaptic strength changes.
Data from: Flexibility, variability and constraint in energy management strategies across vertebrate taxa revealed by long-term heart rate measurements
1) Animals are expected to be judicious in the use of the energy they gain due to the costs and limits associated with its intake. The management of energy expenditure (EE) exhibited by animals has previously been considered in terms of three patterns: the constrained, independent and performance patterns of energy management. These patterns can be interpreted by regressing daily EE against maintenance EE measured over extended periods. From the multiple studies on this topic, there is equivocal evidence about the existence of universal patterns in certain aspects of energy management. 2) The implicit assumption that animals exhibit specifically one of three discrete energy management patterns, and without variation, seems simplistic. We suggest that animals can exhibit gradations of different energy management patterns and that the exact pattern will fluctuate as their environmental context changes. 3) To investigate these ideas, and for possible large-scale patterns in energy management pattern, we analysed long-term heart rate data – a strong proxy for EE – across and within individuals in 16 species of birds, mammals, and fish. 4) Our analyses of 292 individuals representing 46 539 observation-days suggest that vertebrates typically exhibit predominantly the independent or performance energy patterns at the across-individual level, and that the pattern does not associate with taxonomic group. Within individuals, however, animals generally exhibit some degree of energy constraint. Together, these findings indicate that across diverse species, some individuals supply more energy to all aspects of their life than do others, however all individuals must trade-off deployment of their available energy between competing functions. This demonstrates that within-individual analyses are essential for interpretation of energy management patterns. 5) We also found that species do not necessarily exhibit a fixed energy management pattern but rather temporal variation in their energy management over the year. Animals' energy management exhibited stronger energy constraint during periods of higher EE, which typically coincided with clear and key life cycle events such as reproduction, suggesting an adaptive plasticity to respond to fluctuating energy demands.
Data from: Accounting for long-term directional trends on year-to-year synchrony in species fluctuations
What determines the stability of communities under environmental fluctuations remains one of the most debated questions in ecology. Scholars generally agree that the similarity in year-to-year fluctuations between species is an important determinant of this stability. Concordant fluctuations in species abundances through time (synchrony) decrease stability while discordance in fluctuations (anti-synchrony) should stabilize communities. Researchers have interpreted the community-wide degree of synchrony in temporal fluctuations as the outcome of different processes. However, existing synchrony measures depend not only on year-to-year species fluctuations, but also on long-term directional trends in species composition, for example due to land-use or climate change. The neglected effect of directional trends in species composition could cause an increase in synchrony that is not due to year-to-year fluctuations, as species that simultaneously increase (or decrease) in abundance over time will appear correlated, even if they fluctuate discordantly from year to year. The opposite pattern is also conceivable, where different species show contrasting trends in their abundances, thus overestimating year-to-year anti-synchrony. Therefore, trends in species composition may limit our understanding of potential ecological mechanisms behind synchrony between species. We propose two easily implementable solutions, with corresponding R functions, for testing and accounting for the effect of trends in species composition on overall synchrony. The first approach is based on computing synchrony over the residuals of fitted species trends over time. The second approach, applicable to already existing indices, is based on three-terms local variance, i.e. computing variance over three-years-long, movable windows. We demonstrate these methods using simulations and data from real plant communities under long-term directional changes, discussing when one approach can be preferred. We show that accounting for long-term temporal trends is both necessary and that separation of effect of trends and year-to-year fluctuation provides a better understanding of ecological mechanisms and their connections with ecological theory.
Data from: Biodiversity-ecosystem functioning relationships in a long-term non-weeded field experiment
Many grassland biodiversity experiments show a positive relationship between biodiversity and ecosystem functioning, however, in most these experiments plant communities are established by sowing and natural colonization is prevented by selective weeding of non-sown species. During ecosystem restoration, for example on abandoned fields, plant communities start on bare soil, and diversity is often manipulated in a single sowing event. How such initial plant diversity manipulations influence plant biodiversity development and ecosystem functioning is not well understood. We examined how relationships between taxonomic and functional diversity, biomass production and stability develop over 16 years in non-weeded plots sown with 15 species, 4 species, or that were not sown. We found that sown plant communities become functionally similar to unsown, naturally colonized plant communities. However, initial sowing treatments had long-lasting effects on species composition and taxonomic diversity. We found only few relationships between biomass production, or stability in biomass production, and functional or taxonomic diversity, and the ones we observed were negative. In addition, the cover of dominant plant species was positively related to biomass production and stability. We conclude that effects of introducing plant species at the start of secondary succession can persist for a long time, and that in secondary succession communities with natural plant species dynamics diversity-functioning relationships can be weak or negative. Moreover, our findings indicate that in systems where natural colonization of species is allowed effects of plant dominance may underlie diversity-functioning relationships.
Data from: Long-term nitrogen addition causes the evolution of less cooperative mutualists
Human activities have altered the global nitrogen (N) cycle, and as a result, elevated N inputs are causing profound ecological changes in diverse ecosystems. The evolutionary consequences of this global change have been largely ignored even though elevated N inputs are predicted to cause mutualism breakdown and the evolution of decreased cooperation between resource mutualists. Using a long-term (22 year) N addition experiment, we find that elevated N inputs have altered the legume-rhizobium mutualism (where rhizobial bacteria trade N in exchange for photosynthates from legumes), causing the evolution of less mutualistic rhizobia. Plants inoculated with rhizobium strains isolated from N-fertilized treatments produced 17–30% less biomass and had reduced chlorophyll content compared to plants inoculated with strains from unfertilized control plots. Because the legume-rhizobium mutualism is the major contributor of naturally-fixed N to terrestrial ecosystems, the evolution of less cooperative rhizobia may have important environmental consequences.
Long-term logging residue loadings affect tree growth but not soil nutrients in lodgepole pine forests
<p>Both above- and below-ground characteristics are affected by logging residue loadings. Long-term monitoring of tree growth and soil nutrients was conducted. We found that tree growth but not soil nutrients were affected. There were dynamic relationships between tree growth and logging residue loadings.</p>
Data from: Constant and cycling incubation temperatures have long-term effects on the morphology and metabolic rate of Japanese quail
Incubation temperature can have profound effects on growth and development of embryos and young birds. However, few studies have examined the role that cycling incubation temperature may play in phenotypic variation and whether these effects persist to adulthood. We incubated Japanese quail eggs at control temperatures (37.5°C), at low temperatures (36.0°C), and under a cyclical treatment that maintained the same average temperature as the low treatment (36.0°C) with high temperatures that were the same as the control (37.5°C) and low temperatures that still allowed for development of the embryo (28.0°C). Individuals in the low treatment group were smaller in mass and size than individuals in the control group but had an increased basal metabolic rate relative to individuals in the cyclical treatment group. Temperature cycling offset the effects of low incubation temperatures on metabolic rate and embryonic development but not the effects on adult mass and size. Although Japanese quail are sexually size dimorphic, with females larger than males, we could detect no evidence of sex-specific sensitivity to suboptimal incubation temperatures. These results highlight the importance of incubation temperature and pattern as sources of morphological and physiological variation of adult birds.
Data from: Deciphering the associations between soil microbial diversity and ecosystem multifunctionality driven by long-term fertilization management
1.An increasing number of studies indicate that microbial diversity plays a crucial role in the mediation of ecosystem multifunctionality (EMF) in natural ecosystems. However, this point remains mostly overlooked in managed ecosystems, especially in agriculture. 2.Here, we compiled promising strategies for the targeted exploitation of the associations between microbial diversity and EMF of agricultural soils using samples from two long-term (more than 30 years) experimental field sites in southern China. The two sites experienced a similar subtropical monsoon climate and fertilization management practices. We used high-throughput amplicon sequencing, structural equation modeling (SEM), and random forest analysis, to analyze our data and validate our hypotheses. 3.We found that soil physiochemical properties and the C-, N-, P- and S-cycle enzyme activities were increased with the increase of microbial diversity. Specifically, a positive linear relationship was observed between microbial diversity and EMF, which was mediated by long-term fertilization management via changes in soil microbial communities and physiochemical properties. Random forest analysis and SEM showed that the important role of microbial diversity on EMF was maintained even when simultaneously taking multiple multifunctionality drivers (soil physiochemical properties, soil aggregation and enzymatic patterns) into account. In addition, microbial diversity, C-cycle enzyme activity and pH value are feasible predictors of EMF; these factors were shown to be the main drivers of EMF of arable soils. 4. Our findings suggest that there may be a limited degree of multifunctional redundancy in arable soils. The relationship we observed between microbial diversity and EMF suggests that management practices that foster more diverse soil microbial communities may have the potential to improve the functioning of agroecosystems.
Data from: Long-term impacts of variable retention harvesting on ground-layer plant communities in Pinus resinosa forests
Concerns about loss of biodiversity and structural complexity in managed forests have recently increased and led to the development of new management strategies focused on restoring or maintaining ecosystem functions while also providing wood outputs. Variable Retention Harvest (VRH) systems, in which mature overstorey trees are retained in various spatial arrangements across harvested areas, represent one potential approach to this problem. However, long-term evaluations of the effectiveness of this strategy at sustaining plant community composition are needed as this strategy is increasingly applied in managed forest landscapes throughout the world. The forest ground layer plays a central role in forest ecosystem functioning and we evaluated the long-term (11+ year) dynamics in ground-layer plant communities in response to VRH study in Pinus resinosa Aiton. forests. This large-scale, manipulative study included four overstorey (control, small gap-aggregated, large gap-aggregated and dispersed) and two understorey (ambient and reduced shrubs) treatments replicated four times in 16 ha stands. Changes in ground-layer community composition were apparent 11 years following harvest, regardless of live-tree retention pattern. Richness and diversity increased and were driven by introduction and colonization of ruderal species, while forest interior species continued to persist across treatments. All life-forms responded positively to harvest with the exception of moss and clubmoss species. The lack of effect of spatial pattern of retention on ground-layer plant communities was likely related to the presence of a dense and persistent shrub layer, a result of decades of fire suppression. In particular, the greatest responses to overstorey retention pattern occurred in areas receiving shrub reduction treatments, indicating this recalcitrant layer likely filtered response to retention pattern. Synthesis and applications. Overall, this work highlights flexibility in choosing a Variable Retention Harvest (VRH) approach when sustaining ground-layer plant community diversity and composition are goals, but altered disturbance regimes (e.g. fire suppression, timber harvesting) that have facilitated the presence or formation of recalcitrant understories, need to be considered. The legacy effects of historical land use and alterations to natural disturbance regimes on the understorey in northern temperate forests are of equal, if not greater importance to overstorey retention patterns, in eliciting desired responses to VRH and need to be more carefully considered in future applications of this method.
Data from: Evolution of long-term coloration trends with biochemically unstable ingredients
The evolutionarily persistent and widespread use of carotenoid pigments in animal coloration contrasts with their biochemical instability. Consequently, evolution of carotenoid-based displays should include mechanisms to accommodate or limit pigment degradation. In birds, this could involve two strategies: (i) evolution of a moult immediately prior to the mating season, enabling the use of particularly fast-degrading carotenoids and (ii) evolution of the ability to stabilize dietary carotenoids through metabolic modification or association with feather keratins. Here, we examine evolutionary lability and transitions between the two strategies across 126 species of birds. We report that species that express mostly unmodified, fast-degrading, carotenoids have pre-breeding moults, and a particularly short time between carotenoid deposition and the subsequent breeding season. Species that expressed mostly slow-degrading carotenoids in their plumage accomplished this through increased metabolic modification of dietary carotenoids, and the selective expression of these slow-degrading compounds. In these species, the timing of moult was not associated with carotenoid composition of plumage displays. Using repeated samples from individuals of one species, we found that metabolic modification of dietary carotenoids significantly slowed their degradation between moult and breeding season. Thus, the most complex and colourful ornamentation is likely the most biochemically stable in birds, and depends less on ecological factors, such as moult timing and migration tendency. We suggest that coevolution of metabolic modification, selective expression and biochemical stability of plumage carotenoids enables the use of unstable pigments in long-term evolutionary trends in plumage coloration.
Data from: Plant, soil and microbial controls on grassland diversity restoration: a long-term, multi-site mesocosm experiment
The success of grassland biodiversity restoration schemes is determined by many factors; as such their outcomes can be unpredictable. There is a need for improved understanding of the relative importance of belowground factors to restoration success, such as contrasting soil type and management intensities, as well as plant community composition and order of assembly. We carried out an eight-year mesocosm experiment across three locations in the UK to explore the relative and interactive roles of various aboveground and belowground factors in the establishment of target species, to determine general constraints on grassland restoration. Each location had a series of mesocosms with contrasting soil types and management status, which were initially sown with six grasses typical of species-poor grasslands targeted for restoration. Over five years, sets of plant species were added, to test how different vegetation treatments, including early-coloniser species and the hemiparasite Rhinanthus minor, and soil type and management, influenced the establishment of target plant species and community diversity. The addition of early-coloniser species to model grasslands suppressed the establishment of target species, indicating a strong priority effect. Soil type was also an important factor, but effects varied considerably across locations. In the absence of early-coloniser species, low soil nutrient availability improved establishment of target species across locations, although R. minor had no beneficial effect. Synthesis and applications. Our long-term, multi-site study indicates that successful restoration of species rich grassland is dependent primarily on priority effects, especially in the form of early-coloniser species that suppress establishment of slow-growing target species. We also show that priority effects vary with soil conditions, being stronger in clay than sandy soils, and on soils of high nutrient availability. As such, our work emphasises the importance of considering priority effects and local soil conditions in developing management strategies for restoring plant species diversity in grassland.
Data from: Ecological and evolutionary dynamics of coexisting lineages during a long-term experiment with E. coli
Closely related organisms usually occupy similar ecological niches, leading to intense competition and even extinction. Such competition also can promote rapid phenotypic evolution and ecological divergence. This process may end with the stable occupation of distinct niches or, alternatively, may entail repeated bouts of evolution. Here we examine two Escherichia coli lineages, called L and S, that coexisted for more than 30,000 generations after diverging from a common ancestor. Both lineages underwent sustained phenotypic evolution based on global transcription and resource utilization profiles, with L seeming to encroach over time on the catabolic profile of S. Reciprocal invasion experiments with L and S clones from the same or different generations revealed evolutionary changes in their interaction, including an asymmetry that confirmed the encroachment by L on the niche of the S lineage. In general, L and S clones from the same generation showed negative frequency-dependent effects, consistent with stable coexistence. However, L clones could invade S clones from both earlier and later generations, whereas S clones could invade only L clones from earlier generations. In this system, the long-term coexistence of competing lineages evidently depended on successive rounds of evolution, rather than on initial divergence followed by a static equilibrium.
Data from: Long-term use benefits of personal frequency-modulated systems for speech in noise perception in patients with stroke with auditory processing deficits: a non-randomised controlled trial study
Objectives: Approximately one in five stroke survivors suffer from difficulties with speech reception in noise, despite normal audiometry. These deficits are treatable with personal Frequency Modulated systems (FMs). This study aimed to evaluate long term benefits in speech reception in noise, after daily 10 week use of personal FMs, in non-aphasic stroke patients with auditory processing deficits. Design: This was a prospective non randomised controlled trial study. Patients were allocated to an intervention care group or standard care subjects group according to their willingness to use the intervention or not. Setting: Tertiary care setting. Participants: Nine non-aphasic subjects with ischemic stroke, normal/near normal audiometry, and auditory processing deficits and with reported difficulties understanding speech in background noise were recruited in the subacute stroke stage (3-12 months after stroke). Interventions: Four patients (intervention care subjects) used the FMs in their daily life over 10 weeks. Five patients (standard care subjects) received standard care. Primary outcome measures: All subjects were tested at baseline (visit 1) and 10 weeks later (visit 2) on a sentences in noise test with the FMs (aided) and without the FMs (unaided). Results: Speech reception thresholds showed clinically and statistically significant improvements in intervention but not in standard care subjects at 10 weeks in both aided and unaided conditions. Conclusions: 10 week use of FM systems by adult stroke patients may lead to benefits in unaided speech in noise perception. Our findings may indicate auditory plasticity type changes and require further investigation.
Data from: Sustained fitness gains and variability in fitness trajectories in the long-term evolution experiment with Escherichia coli
Many populations live in environments subject to frequent biotic and abiotic changes. Nonetheless, it is interesting to ask whether an evolving population's mean fitness can increase indefinitely, and potentially without any limit, even in a constant environment. A recent study showed that fitness trajectories of Escherichia coli populations over 50 000 generations were better described by a power-law model than by a hyperbolic model. According to the power-law model, the rate of fitness gain declines over time but fitness has no upper limit, whereas the hyperbolic model implies a hard limit. Here, we examine whether the previously estimated power-law model predicts the fitness trajectory for an additional 10 000 generations. To that end, we conducted more than 1100 new competitive fitness assays. Consistent with the previous study, the power-law model fits the new data better than the hyperbolic model. We also analysed the variability in fitness among populations, finding subtle, but significant, heterogeneity in mean fitness. Some, but not all, of this variation reflects differences in mutation rate that evolved over time. Taken together, our results imply that both adaptation and divergence can continue indefinitely—or at least for a long time—even in a constant environment.
Data from: Information content is more important than sensory system or physical distance in guiding the long-term evolutionary relationships between signaling modalities in Sceloporus lizards
Long-term signal evolution is shaped by a variety of selective pressures including the need to convey additional information or to improve message transfer to specific receivers or through multiple environments. Here, we test the relative importance of information and sensory modality in shaping the long-term evolution of multimodal signals in Sceloporus lizards. To broadcast identity at territorial boundaries, male Sceloporus use both visual motion (headbob) and chemical signals, whereas they use color (blue belly patches) to signal aggression. Using modern phylogenetic comparative methods, we found a negative correlation between evolutionary changes in visual motion (headbobs) and chemical (femoral pore) signals, but only indirect ties between the evolution of color and motion signals (both of which are perceived visually) through viviparity, and no evidence of an evolutionary link between color and chemical signals. We also find a negative correlation between arboreality and chemical signals. Thus, information content (in this case, broadcasting individual identity versus signaling aggression) appears to play a more important role than sensory modality or physical distance in guiding long-term signal evolution. Additional insights into the underlying evolutionary processes are described, illustrating the utility of a phylogenetic approach.
Data from: Functional diversity of Collembola is reduced in soils subjected to short-term, but not long-term, geothermal warming
1. Human activities have caused global changes of atmospheric chemistry resulting in increased temperature especially in the colder regions of the northern hemisphere. Since warming of the environment can have drastic effects on terrestrial ecosystems it is important to experimentally evaluate the extent of such effects in long-term field-based experiments. In the present study we make use of both recent (short-term) and long-term geothermal warming of Icelandic soils to examine the responses of Collembola, an ecologically important group of soil invertebrates, to warming. 2. Based on metabolic scaling theory, we hypothesized that species of small size would be more successful in warmed soils than species of larger size. Further we expected that top-soil dwelling species would benefit more from warming than deep-soil dwelling species. In order to test these hypotheses we sampled Collembola along replicated gradients of increasing temperature in areas that had been heated for about six years and more than 50 years, respectively. Collembola were identified to species level, counted, and the community-weighted mean trait scores for six functional and ecological traits were calculated. 3. Results show that both short-term and long-term soil warming caused a shift towards a higher relative abundance of species with small body size. Further, abundance of top-soil dwelling Collembola tended to increase after short-term warming, but the opposite was observed after long-term warming. 4. Using trait-based diversity indices (Frich and RaoQ), we show that functional richness and diversity of Collembola communities was significantly reduced (almost halved) as a result of short-term soil warming to about 10 °C above normal, but this effect was not detected in plots equally warmed for more than 50 years. This indicates that the functional diversity of Collembola communities have high resilience towards soil warming in a long-term perspective.
Data from: Soil acidification exerts a greater control on soil respiration than soil nitrogen availability in grasslands subjected to long-term nitrogen enrichment
Terrestrial ecosystems worldwide are receiving increasing amounts of biologically reactive nitrogen (N) as a consequence of anthropogenic activities. This intended or unintended fertilization can have a wide-range of impacts on biotic communities and hence on soil respiration. Reduction in below-ground carbon (C) allocation induced by high N availability has been assumed to be a major mechanism determining the effects of N enrichment on soil respiration. In addition to increasing available N, however, N enrichment causes soil acidification, which may also affect root and microbial activities. The relative importance of increased N availability vs. soil acidification on soil respiration in natural ecosystems experiencing N enrichment is unclear. We conducted a 12-year N enrichment experiment and a 4-year complementary acid addition experiment in a semi-arid Inner Mongolian grassland. We found that N enrichment had contrasting effects on root and microbial respiration. N enrichment significantly increased root biomass, root N content and specific root respiration, thereby promoting root respiration. In contrast, N enrichment significantly suppressed microbial respiration likely by reducing total microbial biomass and changing the microbial community composition. The effect on root activities was due to both soil acidity and increased available N, while the effect on microbes primarily stemmed from soil acidity, which was further confirmed by results from the acid addition experiment. Our results indicate that soil acidification exerts a greater control than soil N availability on soil respiration in grasslands experiencing long-term N enrichment. These findings suggest that N-induced soil acidification should be included in predicting terrestrial ecosystem C balance under future N deposition scenarios.
Data from: Cytoskeletal stability and metabolic alterations in primary human macrophages in long-term microgravity
The immune system is one of the most affected systems of the human body during space flight. The cells of the immune system are exceptionally sensitive to microgravity. Thus, serious concerns arise, whether space flight associated weakening of the immune system ultimately precludes the expansion of human presence beyond the Earth's orbit. For human space flight, it is an urgent need to understand the cellular and molecular mechanisms by which altered gravity influences and changes the functions of immune cells. The CELLBOX-PRIME (= CellBox-Primary Human Macrophages in Microgravity Environment) experiment investigated for the first time microgravity-associated long-term alterations in primary human macrophages, one of the most important effector cells of the immune system. The experiment was conducted in the U.S. National Laboratory on board of the International Space Station ISS using the NanoRacks laboratory and Biorack type I standard CELLBOX EUE type IV containers. Upload and download were performed with the SpaceX CRS-3 and the Dragon spaceship on April 18th, 2014 / May 18th, 2014. Surprisingly, primary human macrophages exhibited neither quantitative nor structural changes of the actin and vimentin cytoskeleton after 11 days in microgravity when compared to 1g controls. Neither CD18 or CD14 surface expression were altered in microgravity, however ICAM-1 expression was reduced. The analysis of 74 metabolites in the cell culture supernatant by GC-TOF-MS, revealed eight metabolites with significantly different quantities when compared to 1g controls. In particular, the significant increase of free fucose in the cell culture supernatant was associated with a significant decrease of cell surface-bound fucose. The reduced ICAM-1 expression and the loss of cell surface-bound fucose may contribute to functional impairments, e.g. the activation of T cells, migration and activation of the innate immune response. We assume that the surprisingly small and non-significant cytoskeletal alterations represent a stable "steady state" after adaptive processes are initiated in the new microgravity environment. Due to the utmost importance of the human macrophage system for the elimination of pathogens and the clearance of apoptotic cells, its apparent robustness to a low gravity environment is crucial for human health and performance during long-term space missions.
Data from: Serum copeptin and neuron specific enolase are markers of neonatal distress and long-term neurodevelopmental outcome
The objective of this study was to evaluate the early changes in serial serum levels of copeptin and neuron-specific enolase (NSE) in neonates diagnosed with birth asphyxia, and to determine whether these biomarkers measured in the first 168 hours after birth are predictive of long-term neurodevelopmental outcome. Copeptin and NSE levels were measured from serum samples collected 6, 12, 24, 48, 72, and 168 hours after birth from 75 term neonates diagnosed with hypoxic-ischemic encephalopathy (HIE) and treated with therapeutic hypothermia for 72 hours. In addition, serum copeptin levels after birth were measured from 10 HIE diagnosed neonates, who were randomized to the normothermic arm of the TOBY cohort. All neonates underwent neurodevelopmental assessment using the Bayley Scales of Infant and Toddler Development-II at two years of age. Copeptin levels were highest at 6 hours after birth and steadily decreased, whereas the highest NSE levels were measured at 24 hours after birth. The biomarker levels correlated with blood-gas parameters (base excess, pH and lactate) at 6 and 12 hours after birth. Copeptin and NSE levels in the early postnatal period were significantly higher in neonates with poor outcome compared to those with favorable outcome at two years of age. Furthermore, in the TOBY cohort, copeptin levels were significantly lower in hypothermic compared to normothermic neonates. To conclude, copeptin and NSE measured in the early postnatal period are potential prognostic biomarkers of long-term neurodevelopmental outcome in term neonates diagnosed with HIE and treated with therapeutic hypothermia.
Data from: Long-term heavy reindeer grazing promotes plant phosphorus limitation in arctic tundra
1. The potential of large mammalian herbivores to shift plant communities between nitrogen (N) and phosphorus (P) limitation has received little attention so far. However, herbivores can influence the cycling of these growth-limiting nutrients, and thereby affect plant nutrient limitation and productivity. Tundra ecosystems are nutrient-poor and commonly grazed by large herbivores like reindeer and may thus be responsive to such changes. 2. Here we examined the effect of long-term light and heavy reindeer grazing on nutrient limitation of plant growth in a Scandinavian arctic tundra. We are the first to conduct a factorial N and P fertilization experiment across the two grazing regimes in two functionally contrasting vegetation types: heath and meadow. 3. Annual primary productivity (APP) showed contrasting responses to our fertilization treatments under light and heavy grazing. Under light grazing, APP increased in response to N + P additions in both the heath and meadow. Under heavy grazing, APP increased in response to N in the heath, with an additional positive effect of N + P combined, while APP increased in response to P and N + P additions in the meadow. 4. These results clearly show that an increase in the grazing intensity of reindeer facilitated a shift towards more P limited conditions in Scandinavian arctic tundra, by increasing N cycling without having a corresponding positive effect on P cycling. In the N-poor heath, reindeer increased soil N availability at least partly due to a shift towards more N-rich graminoids, while in the meadow reindeer decreased soil P availability. The mechanisms behind this decrease remain unclear, but reindeer may simply export more P from the system than N due to their large P demand for the production of their antlers. 5. Synthesis. We conclude that heavy and long-term reindeer grazing promoted a more P limited tundra, thus experimentally confirming the potential of large mammalian herbivores to influence nutrient limitation of plant growth.
ScienceDex guides
Understand access before you commit
These curated guides explain access requirements, typical timelines, costs, and reuse considerations for widely used research datasets.
Allen Brain Atlas
Allen Brain Atlas is an Allen Institute collection of brain map atlases, datasets, APIs, and analysis tools covering mouse, human, and non-human primate brain resources.
Annotated Behaviour and Observability Dataset (ABODe)
ABODe is a University of Edinburgh DataShare dataset for behavior classification in group-housed mice using home-cage video, identities, bounding boxes, ground-plate positions, and annotator labels.
DANDI Archive for NWB datasets
DANDI is a BRAIN Initiative archive for publishing and sharing neurophysiology data, including electrophysiology, optophysiology, and behavioral data packaged as NWB and related standards.
International Brain Laboratory public data
The International Brain Laboratory public data releases expose standardized mouse decision-making experiments, including Neuropixels recordings, widefield calcium imaging, behavior, and session metadata accessed through the ONE API.
OpenNeuro
OpenNeuro is a free, open platform for sharing neuroimaging datasets, with public search, dataset pages, and download paths for web, S3, DataLad, and the OpenNeuro CLI.