2,099 research outputs found
Social immunity of the family: parental contributions to a public good modulated by brood size.
Social immunity refers to any immune defence that benefits others, besides the individual that mounts the response. Since contributions to social immunity are known to be personally costly, they are contributions to a public good. However, individuals vary in their contributions to this public good and it is unclear why. Here we investigate whether they are responding to contributions made by others with experiments on burying beetle (Nicrophorus vespilloides) families. In this species, females, males and larvae each contribute to social immunity through the application of antimicrobial exudates upon the carrion breeding resource. We show experimentally that mothers reduce their contributions to social immunity when raising large broods, and test two contrasting hypotheses to explain why. Either mothers are treating social immunity as a public good, investing less in social immunity when their offspring collectively contribute more, or mothers are trading off investment in social immunity with investment in parental care. Overall, our experiments yield no evidence to support the existence of a trade-off between social immunity and other parental care traits: we found no evidence of a trade-off in terms of time allocated to each activity, nor did the relationship between social immunity and brood size change with female condition. Instead, and consistent with predictions from models of public goods games, we found that higher quality mothers contributed more to social immunity. Therefore our results suggest that mothers are playing a public goods game with their offspring to determine their personal contribution to the defence of the carrion breeding resource.AD was supported by NERC grant NE/H019731/1 to RMK. ODeG was supported by the Cambridge Trust and the Mexican Council for Science and Technology (CONACyT). RMK was supported in part by ERC Consolidators grant 310785 BALDWINIAN_BEETLES. SCC was supported by a NERC fellowship (NE/H014225/2), CER was supported by a Department for Employment and Learning PhD studentship. We thank A. Backhouse for help in maintaining the burying beetle population. We thank two anonymous reviewers for helpful comments on the manuscript.This is the final version of the article. It was first available from Springer via http://dx.doi.org/10.1007/s10682-015-9806-
Momentum-resolved resonant inelastic soft X-ray scattering (qRIXS) endstation at the ALS
A momentum resolved resonant inelastic X-ray scattering (qRIXS) experimental station with continuously rotatable spectrometers and parallel detection is designed to operate at different beamlines at synchrotron and free electron laser (FEL) facilities. This endstation, currently located at the Advanced Light Source (ALS), has five emission ports on the experimental chamber for mounting the high-throughput modular soft X-ray spectrometers (MXS) [24]. Coupled to the rotation from the supporting hexapod, the scattered X-rays from 27.5° (forward scattering) to 152.5° (backward scattering) relative to the incident photon beam can be recorded, enabling the momentum-resolved RIXS spectroscopy. The components of this endstation are described in details, and the preliminary RIXS measurements on highly oriented pyrolytic graphite (HOPG) reveal the low energy vibronic excitations from the strong electron-phonon coupling at C K edge around σ* band. The grating upgrade option to enhance the performance at low photon energies is presented and the potential of this spectroscopy is discussed in summary
Correlation of HTLV-1 proviral load and lymphocyte proliferation from asymptomatic HTLV-1-positive patients and HAM/TSP patients associated or not to skin disorders
A critical evaluation of automatic atom mapping algorithms and tools
The identification of the atoms which change their position in chemical reactions is an important knowledge within the field of Metabolic Engineering. This can lead to new advances at different levels from the reconstruction of metabolic networks to the classification of chemical reactions, through the identification of the atomic changes inside a reaction. The Atom Mapping approach was initially developed in the 1960s, but recently suffered important advances, being used in diverse biological and biotechnological studies. The main methodologies used for atom mapping are the Maximum Common Substructure and the Linear Optimization methods, which both require computational know-how and powerful resources to run the underlying tools.
In this work, we assessed a number of previously implemented atom mapping frameworks, and built a framework able of managing the different data inputs and outputs, as well as the mapping process provided by each of these third-party tools. We evaluated the admissibility of the calculated atom maps from different algorithms, also assessing if with different approaches we were capable of returning equivalent atom maps for the same chemical reaction.ERDF -European Regional Development Fund(UID/BIO/04469/2013)info:eu-repo/semantics/publishedVersio
Effects of riparian plant diversity loss on aquatic microbial decomposers become more pronounced at longer times
We examined the potential long-term impacts of riparian plant diversity loss on diversity and activity of aquatic microbial decomposers. Microbial assemblages were obtained
in a mixed-forest stream by immersion of mesh bags contain-ing three leaf species (alder, oak and eucalyptus), commonly
found in riparian corridors of Iberian streams. Simulation of
species loss was done in microcosms by including a set of all
leaf species, retrieved from the stream, and non-colonized
leaves of three, two or one leaf species. Leaves were renewed
every month throughout six months, and microbial inoculum
was ensured by a set of colonized leaves from the previous
month. Microbial diversity, leaf mass loss and fungal biomass
were assessed at the second and sixth months after plant
species loss. Molecular diversity of fungi and bacteria, as the
total number of operational taxonomic units per leaf diversity
treatment, decreased with leaf diversity loss. Fungal biomass
tended to decrease linearly with leaf species loss on oak and
eucalyptus, suggesting more pronounced effects of leaf diver-sity on lower quality leaves. Decomposition of alder and
eucalyptus leaves was affected by leaf species identity, mainly
after longer times following diversity loss. Leaf decomposi-tion of alder decreased when mixed with eucalyptus, while
decomposition of eucalyptus decreased in mixtures with oak.
Results suggest that the effects of leaf diversity on microbial
decomposers depended on leaf species number and also on
which species were lost from the system, especially after
longer times. This may have implications for the management
of riparian forests to maintain stream ecosystem functioning.FEDER-POFC-COMPETE and the Portuguese
Foundation for Science and Technology supported this study (PEst-C/
BIA/UI4050/2011, PTDC/AAC-AMB/113746/2009 and PTDC/AAC-AMB/117068/2010), S. Duarte (SFRH/BPD/47574/2008) and I.
Fernandes (SFRH/BD/42215/2007)
Emergent global patterns of ecosystem structure and function from a mechanistic general ecosystem model
Anthropogenic activities are causing widespread degradation of ecosystems worldwide, threatening the ecosystem services upon which all human life depends. Improved understanding of this degradation is urgently needed to improve avoidance and mitigation measures. One tool to assist these efforts is predictive models of ecosystem structure and function that are mechanistic: based on fundamental ecological principles. Here we present the first mechanistic General Ecosystem Model (GEM) of ecosystem structure and function that is both global and applies in all terrestrial and marine environments. Functional forms and parameter values were derived from the theoretical and empirical literature where possible. Simulations of the fate of all organisms with body masses between 10 µg and 150,000 kg (a range of 14 orders of magnitude) across the globe led to emergent properties at individual (e.g., growth rate), community (e.g., biomass turnover rates), ecosystem (e.g., trophic pyramids), and macroecological scales (e.g., global patterns of trophic structure) that are in general agreement with current data and theory. These properties emerged from our encoding of the biology of, and interactions among, individual organisms without any direct constraints on the properties themselves. Our results indicate that ecologists have gathered sufficient information to begin to build realistic, global, and mechanistic models of ecosystems, capable of predicting a diverse range of ecosystem properties and their response to human pressures
The first Galaxy scale hunt for the youngest high-mass protostars
The origin of massive stars is a fundamental open issue in modern astrophysics. Pre-ALMA interferometric studies reveal precursors to early B to late O type stars with collapsing envelopes of 15-20 M on 1000-3000 AU size-scales. To search for more massive envelopes we selected the most massive nearby young clumps from the ATLASGAL survey to study their protostellar content with ALMA. Our first results using the intermediate scales revealed by the ALMA ACA array providing 3-5" angular resolution, corresponding to 0.05-0.1 pc size-scales, reveals a sample of compact objects. These massive dense cores are on average two-times more massive than previous studies of similar types of objects. We expect that once the full survey is completed, it will provide a comprehensive view on the origin of the most massive stars
The effects of long-term endurance training on the immune and endocrine systems of elderly men: the role of cytokines and anabolic hormones
BACKGROUND: a decline in immune and endocrine function occurs with aging. The main purpose of this study was to investigate the impact of long-term endurance training on the immune and endocrine system of elderly men. The possible interaction between these systems was also analysed. RESULTS: elderly runners showed a significantly higher T cell proliferative response and IL-2 production than sedentary elderly controls. IL-2 production was similar to that in young adults. Their serum IL-6 levels were significantly lower than their sedentary peers. They also showed significantly lower IL-3 production in comparison to sedentary elderly subjects but similar to the youngs. Anabolic hormone levels did not differ between elderly groups and no clear correlation was found between hormones and cytokine levels. CONCLUSION: highly conditioned elderly men seem to have relatively better preserved immune system than the sedentary elderly men. Long-term endurance training has the potential to decelerate the age-related decline in immune function but not the deterioration in endocrine function
TRY plant trait database - enhanced coverage and open access
Plant traits-the morphological, anatomical, physiological, biochemical and phenological characteristics of plants-determine how plants respond to environmental factors, affect other trophic levels, and influence ecosystem properties and their benefits and detriments to people. Plant trait data thus represent the basis for a vast area of research spanning from evolutionary biology, community and functional ecology, to biodiversity conservation, ecosystem and landscape management, restoration, biogeography and earth system modelling. Since its foundation in 2007, the TRY database of plant traits has grown continuously. It now provides unprecedented data coverage under an open access data policy and is the main plant trait database used by the research community worldwide. Increasingly, the TRY database also supports new frontiers of trait-based plant research, including the identification of data gaps and the subsequent mobilization or measurement of new data. To support this development, in this article we evaluate the extent of the trait data compiled in TRY and analyse emerging patterns of data coverage and representativeness. Best species coverage is achieved for categorical traits-almost complete coverage for 'plant growth form'. However, most traits relevant for ecology and vegetation modelling are characterized by continuous intraspecific variation and trait-environmental relationships. These traits have to be measured on individual plants in their respective environment. Despite unprecedented data coverage, we observe a humbling lack of completeness and representativeness of these continuous traits in many aspects. We, therefore, conclude that reducing data gaps and biases in the TRY database remains a key challenge and requires a coordinated approach to data mobilization and trait measurements. This can only be achieved in collaboration with other initiatives
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