Find research datasets worth reusing

opencc-zeroOct 2021View details →

Vertical stratification collapses under seasonal shifts in climate

Aim: Tropical forests are vertically complex, and offer unique niche opportunities in the form of climate-, habitat-, and resource-gradients from ground to canopy. Rainforest species organize within this vertical spatial gradient and recent macro-ecological research suggests that the highest levels of vertical stratification occur in structurally complex and climatically stable tropical rainforests. Yet, patterns of verticality are typically derived across latitude, linking annual precipitation regimes to canopy utilization and vertical stratification of communities in space. However, although the tropics are not thermally variable, they do have strong seasonality in rainfall—a temporal component that is missed in macro-scale studies. We hypothesise that verticality of ecological communities responds to seasonality in climate, particularly rainfall. Location: Sierra Llorona, Colón Province, Panama. Taxon: Amphibians. Methods: We performed 121 ground-to-canopy surveys across the wet and dry seasons for amphibians. We calculated species specific and community wide vertical height and abundance shifts between seasons, and separately test the importance of vertical height and season on the vertical distribution of species. Results: Our results show a clear downward shift of 5 m in height in amphibian communities from the wet season to dry season. We also observe significant changes in species composition across vertical strata in both seasons, driven by nestedness in the dry season (loss of species over height), and genuine turnover in the wet season (loss and addition of species over height). Main Conclusions: The exploitation of canopy microhabitats and resources in the wet season resulted in complex patterns of stratification, whereas drying flattened the distribution and simplified the composition of arboreal communities. As such, pattern and process in the vertical dimension is not static in time but rather exists as a dichotomy with inverse patterns between wet and dry seasons. Complex, multidimensional distributions of diverse rainforest communities can be simplified by climatic constraints—an important consideration as anthropogenic climate change increases the magnitude of seasonal swings in temperature and precipitation.

opencc-by-4.0Dec 2020View details →

Drop vertical jump biomechanics following exercise induced muscle damage

Drop vertical jump biomechanical data 0h and 48h following eccentric exercise induced muscle damage of the knee extensors.

opencc-by-4.0Jan 2021View details →

Polyphasic characterization of carbapenem-resistant Klebsiella pneumoniae clinical isolates suggests vertical transmission of the blaKPC-3 gene

Optical DNA mapping (ODM) data related to the study, presented in figures 2-6 in the paper.

opencc-zeroDec 2016View details →

Data from: Coevolution between flight morphology, vertical stratification and sexual dimorphism: what can we learn from tropical butterflies?

Occurrence patterns are partly shaped by the affinity of species with habitat conditions. For winged organisms, flight-related attributes are vital for ecological performance. However, due to the different reproductive roles of each sex, we expect divergence in flight energy budget, and consequently different selection responses between sexes. We used tropical frugivorous butterflies as models to investigate coevolution between flight morphology, sex dimorphism and vertical stratification. We studied 94 species of Amazonian fruit-feeing butterflies sampled in seven sites across 3341 ha. We used wing-thorax ratio as a proxy for flight capacity and hierarchical Bayesian modeling to estimate stratum preference. We detected a strong phylogenetic signal in wing-thorax ratio in both sexes. Stouter fast-flying species preferred the canopy, while more slender slow-flying species preferred the understorey. However, this relationship was stronger in females than in males, suggesting that female phenotype associates more intimately with habitat conditions. Within species, males were stouter than females and sexual dimorphism was sharper in understorey species. Because trait-habitat relationships were independent from phylogeny, the matching between flight morphology and stratum preference is more likely to reflect adaptive radiation than shared ancestry. This study sheds light on the impact of flight and sexual dimorphism on the evolution and ecological adaptation of flying organisms.

opencc-zeroDec 2013View details →

Data from: Vertical distribution of the soil microbiota along a successional gradient in a glacier forefield

Spatial patterns of microbial communities have been extensively surveyed in well-developed soils, but few studies investigated the vertical distribution of microorganisms in newly developed soils after glacier retreat. We used 454-pyrosequencing to assess whether bacterial and fungal community structures differed between stages of soil development (SSD) characterized by an increasing vegetation cover from barren (vegetation cover: 0%/ age: 10 years), sparsely-vegetated (13%/ 60 years), transient (60%/ 80 years) to vegetated (95%/ 110 years) and depths (surface, 5 and 20 cm) along the Damma glacier forefield (Switzerland). Stage of soil development significantly influenced the bacterial and fungal communities. Based on indicator species analyses, metabolically versatile bacteria (e.g. Geobacter) and psychrophilic yeasts (e.g. Mrakia) characterized the barren soils. Vegetated soils with higher C, N and root biomass consisted of bacteria able to degrade complex organic compounds (e.g. Candidatus Solibacter), ligno-cellulolytic Ascomycota (e.g. Geoglossum) and ectomycorrhizal Basidiomycota (e.g. Laccaria). Soil depth only influenced bacterial and fungal communities in barren and sparsely-vegetated soils. These changes were partly due to more silt and higher soil moisture in the surface. In both soil ages, the surface was characterized by OTUs affiliated to Phormidium and Sphingobacteriales. In lower depths, however, bacterial and fungal communities differed between both SSDs. Lower depths of sparsely-vegetated soils consisted of OTUs affiliated to Acidobacteria and Geoglossum whereas depths of barren soils were characterized by OTUs related to Gemmatimonadetes. Overall, plant establishment drives the soil microbiota along the successional gradient but does not influence the vertical distribution of microbiota in recently deglaciated soils.

opencc-zeroDec 2014View details →

Data from: Interaction specificity between leaf-cutting ants and vertically transmitted Pseudonocardia bacteria

Background: The obligate mutualism between fungus-growing ants and microbial symbionts offers excellent opportunities to study the specificity and stability of multi-species interactions. In addition to cultivating fungus gardens, these ants have domesticated actinomycete bacteria to defend gardens against the fungal parasite Escovopsis and possibly other pathogens. Panamanian Acromyrmex echinatior leaf-cutting ants primarily associate with actinomycetes of the genus Pseudonocardia. Colonies are inoculated with one of two vertically transmitted phylotypes (Ps1 or Ps2), and maintain the same phylotype over their lifetime. We performed a cross-fostering experiment to test whether co-adaptations between ants and bacterial phylotypes have evolved, and how this affects bacterial growth and ant prophylactic behavior after infection with Escovopsis. Results: We show that Pseudonocardia readily colonized ants irrespective of their colony of origin, but that the Ps2 phylotype, which was previously shown to be better able to maintain its monocultural integrity after workers became foragers than Ps1, reached a higher final cover when grown on its native host than on alternative hosts. The frequencies of major grooming and weeding behaviors co-varied with symbiont/host combinations, showing that ant behavior also was affected when cuticular actinomycete phylotypes were swapped. Conclusion: These results show that the interactions between leaf-cutting ants and Pseudonocardia bear signatures of mutual co-adaptation within a single ant population.

opencc-zeroDec 2014View details →

Data from: Markov switching autoregressive models for interpreting vertical movement data with application to an endangered marine apex predator

1.Time series of animal movement obtained from bio-loggers are becoming widely used across all taxa. These data are nowadays of high quality, combining high resolution with precision, as the tags are able to collect for longer times and store larger quantities of data. Due to their nature, high-frequency data sequences often pose non-trivial problems in time series analysis: non-linearity, non-Normality, non-stationarity, and long memory. These issues can be tackled by modelling the data sequence as a realization of a stochastic regime switching process. 2. We suggest a novel Markov switching autoregressive model where the hidden Markov chain is non-homogeneous, with time-varying transition probabilities, whose dynamics depend on the dynamics of some contemporary categorical covariates. 3. To illustrate the use of the method, we apply it to the depth profiles of four individuals of flapper skate (Dipturus cf. intermedia) in order to identify swimming behaviours. Individual time series were obtained from data storage tags that recorded pressure every two minutes. The environmental covariates used were lunar phase (a proxy for the spring-neap tidal cycle), lunar cycle, and diel cycle. For all individuals two states (or regimes) were always selected (the autoregressive order was either three or four), representing different regimes of animal activity, i.e., state 1 for resting or horizontal swimming or slow vertical movement; state 2 for fast ascending and descending. The cycle of the four lunar phases was the only environmental covariate that explained the hidden state dynamics in all individuals, whereas lunar cycle was selected for two individuals and diel cycle for one only. 4. The method is an efficient approach to fit one-dimensional tag data using categorical environmental covariates, and to classify the observations into a small number of states representing individual behaviours of tagged individuals.

opencc-zeroDec 2016View details →

Data from: Physiological, morphological, and ecological tradeoffs influence vertical habitat use of deep-diving toothed-whales in the Bahamas

Dive capacity among toothed whales (suborder: Odontoceti) has been shown to generally increase with body mass in a relationship closely linked to the allometric scaling of metabolic rates. However, two odontocete species tagged in this study, the Blainville's beaked whale Mesoplodon densirostris and the Cuvier's beaked whale Ziphius cavirostris, confounded expectations of a simple allometric relationship, with exceptionally long (mean: 46.1 min & 65.4 min) and deep dives (mean: 1129 m & 1179 m), and comparatively small body masses (med.: 842.9 kg & 1556.7 kg). These two species also exhibited exceptionally long recovery periods between successive deep dives, or inter-deep-dive intervals (M. densirostris: med. 62 min; Z. cavirostris: med. 68 min). We examined competing hypotheses to explain observed patterns of vertical habitat use based on body mass, oxygen binding protein concentrations, and inter-deep-dive intervals in an assemblage of five sympatric toothed whales species in the Bahamas. Hypotheses were evaluated using dive data from satellite tags attached to the two beaked whales (M. densirostris, n = 12; Z. cavirostris, n = 7), as well as melon-headed whales Peponocephala electra (n = 13), short-finned pilot whales Globicephala macrorhynchus (n = 15), and sperm whales Physeter macrocephalus (n = 27). Body mass and myoglobin concentration together explained only 36% of the variance in maximum dive durations. The inclusion of inter-deep-dive intervals, substantially improved model fits (R2 = 0.92). This finding supported a hypothesis that beaked whales extend foraging dives by exceeding aerobic dive limits, with the extension of inter-deep-dive intervals corresponding to metabolism of accumulated lactic acid. This inference points to intriguing tradeoffs between body size, access to prey in different depth strata, and time allocation within dive cycles. These tradeoffs and resulting differences in habitat use have important implications for spatial distribution patterns, and relative vulnerabilities to anthropogenic impacts.

opencc-zeroDec 2017View details →

Data from: Distance-decay differs among vertical strata in a tropical rainforest

1. Assemblage similarity decays with geographic distance—a pattern known as the distance-decay relationship. While this pattern has been investigated for a wide range of organisms, ecosystems, and geographical gradients, whether these changes vary more cryptically across different forest strata (from ground to canopy) remains elusive. 2. Here, we investigated the influence of ground vs arboreal assemblages to the general distance-decay relationship observed in forests. We seek to explain differences in distance-decay relationships between strata in the context of the vertical stratification of assemblage composition, richness, and abundance. 3. We surveyed for a climate sensitive model organism, amphibians, across vertical rainforest strata in Madagascar. For each tree, we defined assemblages of ground-dwelling, understory, or canopy species. We calculated horizontal distance-decay in similarity across all trees, and across assemblages of species found in different forest strata (ground, understory, and canopy). 4. We demonstrate that within stratum comparisons exhibit a classic distance-decay relationship for canopy and understory communities but no distance-decay relationships for ground communities. We suggest that differences in horizontal turnover between strata may be due to local scale habitat and resource heterogeneity in the canopy, or the influence of arboreal traits on species dispersal and distribution. 5. Synthesis: Biodiversity patterns in horizontal space were not consistent across vertical space, suggesting that canopy fauna may not play by the same set of 'rules' as their conspecifics living below them on the ground. Our study provides compelling evidence that the above-ground amphibian assemblage of tropical rainforests is the primary driver of the classical distance-decay relationship.

opencc-zeroApr 2020View details →

Data from: Peak vertical jump power predicts radial bone strength better than hand grip strength in healthy individuals

Osteoporosis is considered a pediatric disease with geriatric consequences. However, measuring bone strength in children is complex and creates a practical problem for health professionals, teachers and parents. A non-invasive measure of muscle fitness that correlates to bone strength may provide a means to monitor bone strength throughout the lifespan. Therefore, the purpose of this study was to investigate the relationship between common muscle function tests (relative grip strength (RGS), peak vertical jump power (PP)) and bone strength in the radial diaphysis and epiphysis of a healthy population. Healthy participants (n=147 (81 female)) performed a bilateral grip strength test using a hand dynamometer, and a maximal vertical jump test. Peak vertical jump power was calculated from maximal jump height using the Sayer's equation. Moment of inertia (MoI), cortical area (CoA), cortical bone mineral density (cBMD), and polar strength-strain index (SSIp) were measured using peripheral Quantitative Computed Tomography (pQCT) to determine bone strength parameters at the 66% radial site (predominantly cortical bone). At the 4% site (trabecular bone site), bone mineral content (vBMC.tb), bone mineral density (vBMD.tb), total area (ToA.tb) and bone strength index (BSIc) were measured. Hierarchical multiple regression analyses determined the relationship of each muscle function test for each bone envelope (cortical and trabecular). For the cortical bone measurements: RGS, and PP were both significantly correlated with CoA, MoI, and SSIp. Peak vertical jump power predicted bone strength parameters to a greater extent compared to RGS. For the trabecular bone envelope, RGS was not a predictor of bone strength however peak power was a significant predictor of bone strength parameters. Peak vertical jump power was a significant predictor of bone strength at both trabecular and cortical radial sites. Interestingly PP, a lower limb measurement explained the most variance in the bone strength of the upper limb.

opencc-zeroDec 2017View details →

Data from: Vertical canopy gradient shaping the stratification of leaf-chewer-parasitoid interactions in a temperate forest

Knowledge about herbivores and their parasitoids in forest canopies remains limited, despite their diversity and ecological importance. Thus, it is important to understand the factors that shape the herbivore–parasitoid community structure, particularly the effect of vertical gradient. We investigated a quantitative community dataset of exposed and semiconcealed leaf‐chewing larvae and their parasitoids along a vertical canopy gradient in a temperate forest. We sampled target insects using an elevated work platform in a 0.2 ha broadleaf deciduous forest plot in the Czech Republic. We analyzed the effect of vertical position among three canopy levels (first [lowest], second [middle], and third [highest]) and tree species on community descriptors (density, diversity, and parasitism rate) and food web structure. We also analyzed vertical patterns in density and parasitism rate between exposed and semiconcealed hosts, and the vertical preference of the most abundant parasitoid taxa in relation to their host specificity. Tree species was an important determinant of all community descriptors and food web structure. Insect density and diversity varied with the vertical gradient, but was only significant for hosts. Both host guilds were most abundant in the second level, but only the density of exposed hosts declined in the third level. Parasitism rate decreased from the first to third level. The overall parasitism rate did not differ between guilds, but semiconcealed hosts suffered lower parasitism in the third level. Less host‐specific taxa (Ichneumonidae, Braconidae) operated more frequently lower in the canopy, whereas more host‐specific Tachinidae followed their host distribution. The most host‐specific Chalcidoidea preferred the third level. Vertical stratification of insect density, diversity, and parasitism rate was most pronounced in the tallest tree species. Therefore, our study contradicts the general paradigm of weak arthropod stratification in temperate forest canopies. However, in the network structure, vertical variation might be superseded by variation among tree species.

opencc-zeroDec 2015View details →

Data from: What shapes cerambycid beetle communities in a tropical forest mosaic? Assessing the effects of host tree identity, forest structure, and vertical stratification

Due to anthropogenic activities, tropical rain forests face many challenges in sustaining biodiversity and maintaining global climates. This study explores how forest successional stage, tree composition, and stratum affect communities of saproxylic cerambycid beetles—concealed feeders that play important roles in forest nutrient cycling. Forty trees in five families (Fabaceae, Lecythidaceae, Malvaceae, Moraceae, and Sapotaceae) were sampled in a mosaic of old-growth and secondary forest on the Osa Peninsula, Costa Rica. Bait branches yielded 3549 cerambycid individuals in 49 species. Species richness was almost identical in old-growth and secondary forest, and both yielded specialists, but abundance was higher in old-growth forest. Overall community structure was most strongly influenced by host plant species; within most plant families it was also impacted by forest successional status. Moraceae was the exception, presumably because the focal tree species was abundant in both old-growth and secondary forest. Several host and old-growth specialist species reached high densities within patches of old-growth forest, but seldom colonized apparently suitable trees within secondary forest. This suggests that even small areas of old-growth forest can act as refuges, but that secondary forest may act as a barrier to dispersal. The vulnerability of specialized saproxylic insects to land use change will be linked to the ability of their preferred hosts to disperse to and persist in successional habitats; rearing studies may provide the most accurate method to monitor community changes over time.

opencc-zeroDec 2012View details →

Data from: Vertical distribution of marine invertebrate larvae in response to thermal stratification in the laboratory

We investigated the effect of the presence of an experimentally generated thermocline on the vertical distribution of larval Strongylocentrotus droebachiensis, Asterias rubens and Argopecten irradians. Vertical distributions were recorded over 90 min in rectangular plexiglass thermocline chambers designed to regulate the temperature of a central observation compartment to the desired values. The temperature in the bottom water layer (B) and the temperature difference between layers (ΔT) were manipulated in an orthogonal design. We used, for S. droebachiensis: 4 levels of ΔT (0, 3, 6 and 12 °C) and 3 levels of B (3, 6 and 9 °C); for A. rubens: 3 levels ΔT (0, 6 and 12 °C) and 2 levels of B (6 and 12 °C); and for A. irradians: 3 levels of ΔT (0, 5 and 11 °C) and 2 levels of B (5 and 11 °C). The difference in temperature between water layers did not affect the vertical distribution of echinoderms consistently, while the distribution of A. irradians was limited to the bottom layer when any thermal stratification was present regardless of strength. Our results suggest that the vertical position of larvae of S. droebachiensis and A. rubens is related to the temperatures of the surface layer and that the presence alone or the steepness of the thermocline has less influence on their distribution. Consequently, in the field, echinoderm larvae would aggregate at the surface unless temperature extremes were encountered. In contrast, the position of A. irradians was limited to the bottom layer in the presence of a thermocline of at least 5 °C (the shallowest used in our study). Such thermoclines are common in a natural setting and could affect the vertical distribution and horizontal dispersal of larvae by acting as a barrier to vertical migration.

opencc-zeroDec 2018View details →

Data from: Resolving the heading-direction ambiguity in vertical-beam radar observations of migrating insects

1. Each year, massive numbers of insects fly across the continents at heights of hundreds of metres, carried by the wind, bringing both environmental benefits and serious economic and social costs. To investigate the insects' flight behaviour and their response to winds, entomological radar has proved to be a particularly valuable tool; however, its observations of insect orientation are ambiguous with regard to the head/tail direction and this greatly hinders interpretation of the migrants' flight behaviour. 2. We have developed two related methods of using wind data to resolve the head/tail ambiguity and we have compared their outputs with those from simply assigning the heading direction to be that which is closer to the track direction. We applied all three methods to observations of Australian Plague Locust migrations made with an Insect Monitoring Radar. 3. For the study dataset, some of the headings selected by the simpler method are shown to be clearly incorrect. The two new methods generally agree and reveal a significantly different, and presumably more accurate, relationship of heading direction to track direction. However, use of these methods leads to quite a large proportion of the sample being lost because the wind values, which derive from a regional-scale numerical model, are shown to be incompatible with the radar observations. This exploratory study has moreover demonstrated that locusts are frequently oriented at a large angle to their track, and that quite often their movement is at least slightly tail-first. 4. Both new methods appear to be a significant improvement on the simpler method. As well as providing an accurate representation of migratory flight behaviour, they allow occasions when the model wind values are unreliable to be eliminated from the data sample.

Solar Electric Motor on Superconducting Bearings in Liquid Nitrogen - Vertical Configuration - 190 rpm

A solar electric motor, immersed in liquid nitrogen, and levitated on superconducting bearings, has been designed and tested at the GREEN Laboratory. This video shows the permanent regime that represents a speed around 190 rpm, with a configuration of superconducting bearings called "vertical configuration" and a Plexiglas cylinder around the cubic rotor in order to reduce the frictions in the liquid. It's the same rotor than in [10.5281/zenodo.154095] but the Plexiglas cover has been added, which leads to an increase of the speed from 75 rpm to 190 rpm.

Solar Electric Motor on Superconducting Bearings in Liquid Nitrogen with Propeller - Vertical Configuration - 75 rpm

Solar Electric Motor on Superconducting Bearings - Vertical Configuration - 900 rpm

Solar Electric Motor on Superconducting Bearings - Vertical Configuration - 1350 rpm

A solar electric motor that levitates on superconducting bearings has been designed and tested at the GREEN Laboratory. This video shows the start-up of the motor and the permanent regime that represents a speed around 1350 rpm, with a configuration of superconducting bearings called "vertical configuration". The difference from the video [10.5281/zenodo.154013] is that, the permanent magnet that acts as inductor has been placed in the optimal position.

opennotspecifiedDec 2009View details →

FIGURE 5. Left side shows a in The amphibian community at Yanayacu Biological Station, Ecuador, with a comparison of vertical microhabitat use among Pristimantis species and the description of a new species of the Pristimantis myersi group

FIGURE 5. Left side shows a power spectrum (top), sonogram (middle), and oscillogram (bottom) of a series of advertisement calls of Pristimantis bicantus (QCAZ 18983). Right side shows a sonogram (middle) and oscillogram (bottom) of a single long call (the eighth of the 11 long calls shown on the left, marked with an asterisk). This is an example of a call series consisting of three short calls (each with two pulses) and 11 long calls (each with 17–23 more rapid pulses). The power spectrum was measured along the entire duration of the call series.