31 research outputs found
Enhanced Go and NoGo Learning in Individuals With Obesity
Overeating in individuals with obesity is hypothesized to be partly caused by automatic action tendencies to food cues that have the potential to override goal-directed dietary restriction. Individuals with obesity are often characterized by alterations in the processing of such rewarding food, but also of non-food stimuli, and previous research has suggested a stronger impact on the execution of goal-directed actions in obesity. Here, we investigated whether Pavlovian cues can also corrupt the learning of new approach or withdrawal behavior in individuals with obesity. We employed a probabilistic Pavlovian-instrumental learning paradigm in which participants (29 normal-weight and 29 obese) learned to actively respond (Go learning) or withhold a response (NoGo learning) in order to gain monetary rewards or avoid losses. Participants were better at learning active approach responses (Go) in the light of anticipated rewards and at learning to withhold a response (NoGo) in the light of imminent punishments. Importantly, there was no evidence for a stronger corruption of instrumental learning in individuals with obesity. Instead, they showed better learning across conditions than normal-weight participants. Using a computational reinforcement learning model, we additionally found an increased learning rate in individuals with obesity. Previous studies have mostly reported a lower reinforcement learning performance in individuals with obesity. Our results contradict this and suggest that their performance is not universally impaired: Instead, while previous studies found reduced stimulus-value learning, individuals with obesity may show better action-value learning. Our findings highlight the need for a broader investigation of behavioral adaptation in obesity across different task designs and types of reinforcement learning.Peer Reviewe
Geographic and seasonal patterns and limits on the adaptive response to temperature of European Mytilus spp. and Macoma balthica populations
Seasonal variations in seawater temperature require extensive metabolic acclimatization in cold-blooded organisms inhabiting the coastal waters of Europe. Given the energetic costs of acclimatization, differences in adaptive capacity to climatic conditions are to be expected among distinct populations of species that are distributed over a wide geographic range. We studied seasonal variations in the metabolic adjustments of two very common bivalve taxa at European scale. To this end we sampled 16 populations of Mytilus spp. and 10 Macoma balthica populations distributed from 39° to 69°N. The results from this large-scale comprehensive comparison demonstrated seasonal cycles in metabolic rates which were maximized during winter and springtime, and often reduced in the summer and autumn. Studying the sensitivity of metabolic rates to thermal variations, we found that a broad range of Q10 values occurred under relatively cold conditions. As habitat temperatures increased the range of Q10 narrowed, reaching a bottleneck in southern marginal populations during summer. For Mytilus spp., genetic-group-specific clines and limits on Q10 values were observed at temperatures corresponding to the maximum climatic conditions these geographic populations presently experience. Such specific limitations indicate differential thermal adaptation among these divergent groups. They may explain currently observed migrations in mussel distributions and invasions. Our results provide a practical framework for the thermal ecophysiology of bivalves, the assessment of environmental changes due to climate change and its impact on (and consequences for) aquaculture
Ocean current connectivity propelling the secondary spread of a marine invasive comb jelly across western Eurasia
Publication history: Accepted - 15 February 2018; Published - 16 May 2018.Aim: Invasive species are of increasing global concern. Nevertheless, the mechanisms driving further
distribution after the initial establishment of non-native species remain largely unresolved, especially
in marine systems. Ocean currents can be a major driver governing range occupancy, but this has
not been accounted for in most invasion ecology studies so far. We investigate how well initial
establishment areas are interconnected to later occupancy regions to test for the potential role of
ocean currents driving secondary spread dynamics in order to infer invasion corridors and the
source–sink dynamics of a non-native holoplanktonic biological probe species on a continental scale.
Location: Western Eurasia.
Time period: 1980s–2016.
Major taxa studied: ‘Comb jelly’ Mnemiopsis leidyi.
Methods: Based on 12,400 geo-referenced occurrence data, we reconstruct the invasion history
of M. leidyi in western Eurasia. We model ocean currents and calculate their stability to match the
temporal and spatial spread dynamics with large-scale connectivity patterns via ocean currents.
Additionally, genetic markers are used to test the predicted connectivity between subpopulations.
Results: Ocean currents can explain secondary spread dynamics, matching observed range expansions
and the timing of first occurrence of our holoplanktonic non-native biological probe species,
leading to invasion corridors in western Eurasia. In northern Europe, regional extinctions after cold winters were followed by rapid recolonizations at a speed of up to 2,000 km per season. Source areas hosting year-round populations in highly interconnected regions can re-seed genotypes over
large distances after local extinctions.
Main conclusions: Although the release of ballast water from container ships may contribute to
the dispersal of non-native species, our results highlight the importance of ocean currents driving
secondary spread dynamics. Highly interconnected areas hosting invasive species are crucial for
secondary spread dynamics on a continental scale. Invasion risk assessments should consider
large-scale connectivity patterns and the potential source regions of non-native marine species.Danish Council for Independent Research;
Grant/Award Number: DFF-1325-00102B;
FP7 People: Marie-Curie Actions,
Grant/Award Number: MOBILEX, DFF -
1325-00025; EU, BONUS, BMBF, Grant/
Award Number: 03F0682; Excellence
Cluster “Future Ocean”, Grant/Award
Number: CP153
Finishing the euchromatic sequence of the human genome
The sequence of the human genome encodes the genetic instructions for human physiology, as well as rich information about human evolution. In 2001, the International Human Genome Sequencing Consortium reported a draft sequence of the euchromatic portion of the human genome. Since then, the international collaboration has worked to convert this draft into a genome sequence with high accuracy and nearly complete coverage. Here, we report the result of this finishing process. The current genome sequence (Build 35) contains 2.85 billion nucleotides interrupted by only 341 gaps. It covers ∼99% of the euchromatic genome and is accurate to an error rate of ∼1 event per 100,000 bases. Many of the remaining euchromatic gaps are associated with segmental duplications and will require focused work with new methods. The near-complete sequence, the first for a vertebrate, greatly improves the precision of biological analyses of the human genome including studies of gene number, birth and death. Notably, the human enome seems to encode only 20,000-25,000 protein-coding genes. The genome sequence reported here should serve as a firm foundation for biomedical research in the decades ahead
Retrospective evaluation of whole exome and genome mutation calls in 746 cancer samples
Funder: NCI U24CA211006Abstract: The Cancer Genome Atlas (TCGA) and International Cancer Genome Consortium (ICGC) curated consensus somatic mutation calls using whole exome sequencing (WES) and whole genome sequencing (WGS), respectively. Here, as part of the ICGC/TCGA Pan-Cancer Analysis of Whole Genomes (PCAWG) Consortium, which aggregated whole genome sequencing data from 2,658 cancers across 38 tumour types, we compare WES and WGS side-by-side from 746 TCGA samples, finding that ~80% of mutations overlap in covered exonic regions. We estimate that low variant allele fraction (VAF < 15%) and clonal heterogeneity contribute up to 68% of private WGS mutations and 71% of private WES mutations. We observe that ~30% of private WGS mutations trace to mutations identified by a single variant caller in WES consensus efforts. WGS captures both ~50% more variation in exonic regions and un-observed mutations in loci with variable GC-content. Together, our analysis highlights technological divergences between two reproducible somatic variant detection efforts
Feeding ecology of dunlins Calidris alpina staging in the southern Baltic Sea 2. Spatial and temporal variations in the harvestable fraction of favourite prey Hediste diversicolor.
Abstract The feeding habits of migrating dunlins Calidris alpina staging in different non-tidal coastal habitats in the southern Baltic Sea are described. The study also focuses on the structure of the benthic macrofauna of these habitats and the diet choice of dunlins. All investigations were carried out on Langenwerder Island (Wismar Bay), where different types of flats and beaches harbour a total of 30 to 40 species of marine macrofauna. The composition of the macrobenthos differed considerably between the eulittoral sandbank, the eulittoral mudflat, the pebble beach, and the sublittoral surroundings. Most dunlins were observed foraging in flocks of up to several hundred individuals on the eulittoral flats. Densities of up to 20 to 30 foraging dunlins ha 1 occurred annually during peak migration in September and October. Macrobenthos biomass in these habitats fluctuated between 20 and 40 g AFDM m 2 . The mean total food consumption of dunlins during autumn migration was estimated at 0.01 g AFDM m 2 d 1 . The predation pressure could be estimated at 3 to 6% of the suitable food supply. Dunlins staging on Langenwerder were able to attain a pre-migratory mass gain of 0.2 to 0.5% of their body weight per day within an 8 to 12-h daily feeding period. The birds fed predominantly on the polychaete Hediste diversicolor by probing. They selected small 7 to 31-mm-long individuals. When water levels were high, and the eulittoral flats inundated, many dunlins switched to foraging along the shorelines where a variety of small prey were taken from spilled macrophytes. Dunlins sometimes obviously ignored their most important food H. diversicolor, although available, by feeding on other prey such as juvenile fishes and shrimps, dipteran larvae or spilled amphipods. When feeding on amphipods, dunlins selected the smallest individuals
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Effects of feeding lubabegron on gas emissions, growth performance, and carcass characteristics of beef cattle housed in small-pen environmentally monitored enclosures during the last 3 mo of the finishing period
The development of technologies that promote environmental stewardship while maintaining or improving the efficiency of food animal production is essential to the sustainability of producing a food supply to meet the demands of a growing population. As such, Elanco (Greenfield, IN) pursued an environmental indication for a selective β-modulator (lubabegron; LUB). LUB was recently approved by the United States Food and Drug Administration (FDA) to be fed to feedlot cattle during the last 14 to 91 d of the feeding period for reductions in gas emissions/kg of unshrunk final BW and HCW. A 4 × 2 factorial arrangement of treatments was used with the factors of dose (0.0, 1.38, 5.5, or 22.0 mg·kg-1 DM basis) and sex (steers or heifers). Three 91-d cycles were conducted (112 cattle/cycle) with each dose × sex combination being represented by a single cattle pen enclosure (CPE; 14 cattle/CPE) resulting in a total of 168 steers and 168 heifers (n = 6 replicates/dose). There were no interactions observed between dose and sex for any variable measured in the study (P ≥ 0.063). Five gases were evaluated for all pens based on CPE concentrations relative to ambient air: NH3, CH4, N2O, H2S, and CO2. Cumulative NH3 gas emissions were reduced by feeding cattle 5.5 and 22.0 mg·kg-1 LUB (P ≤ 0.023) and tended (P = 0.076) to be lower for the cattle fed 1.38 mg·kg-1 LUB compared with the negative controls (CON). The cumulative NH3 gas emission reductions of 960 to 1032 g, coupled with HCW increases (P ≤ 0.019) of 15 to 16 kg for all LUB doses vs. CON, led to reductions in NH3 gas emissions/kg HCW for all three LUB treatments (P ≤ 0.004). Similar to HCW, reductions in NH3 gas emissions/kg of unshrunk final BW were observed for all LUB doses (P ≤ 0.009) and were attributable to both decreases in NH3 gas emissions and numerical increases in BW. Dose had no effect on cumulative emissions or emissions standardized by BW or HCW for the other four gases (P ≥ 0.268). LUB is a novel tool to reduce emissions of NH3 gas per kilogram of unshrunk live BW and hot carcass weight
Living Waters
On the occasion of the 15th BMBF Forum for Sustainability (13-14 May 2019) on "Maintaining Biodiversity – Researching for our Future" and the "Research Initiative for the Conservation of Biodiversity", the authors of this Research Agenda underwent an intensive exchange process to identify and coordinate the most important research needs in and on inland waters. The exchange with the "Coastal Research Strategy Group" of the "German Marine Research Consortium" reflects the (original) connectedness of inland and coastal waters. This Research Agenda, presented by the authors, marks the start of a consultation process on the need to conduct research on freshwaters, and at the same time supports the development of the agenda of the BMBF Framework Programme "Research for Sustainable Development (FONA)"