22 research outputs found
Redundant Mechanisms for Regulation of Midline Crossing in Drosophila
During development, all neurons have to decide on whether to cross the longitudinal midline to project on the contralateral side of the body. In vertebrates and invertebrates regulation of crossing is achieved by interfering with Robo signalling either through sorting and degradation of the receptor, in flies, or through silencing of its repulsive activity, in vertebrates. Here I show that in Drosophila a second mechanism of regulation exists that is independent from sorting. Using in vitro and in vivo assays I mapped the region of Robo that is sufficient and required for its interaction with Comm, its sorting receptor. By modifying that region, I generated new forms of Robo that are insensitive to Comm sorting in vitro and in vivo, yet still able to normally translate repulsive activity in vivo. Using gene targeting by homologous recombination I created new conditional alleles of robo that are sorting defective (roboSD). Surprisingly, expression of these modified proteins results in phenotypically normal flies, unveiling a sorting independent mechanism of regulation
Screening of quinalphos, trifluralin and dichlorvos residues in fresh water of aquaculture systems in Mekong Delta, Vietnam
Body Composition in Patients with Radioactive Iodine-Refractory, Advanced Differentiated Thyroid Cancer Treated with Sorafenib or Placebo: A Retrospective Analysis of the Phase III DECISION Trial
Biotic interactions, community assembly, and eco-evolutionary dynamics as drivers of long-term biodiversityâecosystem functioning relationships
The functioning and service provisioning of ecosystems in the face of anthropogenic environmental and biodiversity change is a cornerstone of ecological research. The last three decades of biodiversityâecosystem functioning (BEF) research have provided compelling evidence for the significant positive role of biodiversity in the functioning of many ecosystems. Despite broad consensus of this relationship, the underlying ecological and evolutionary mechanisms have not been well understood. This complicates the transition from a description of patterns to a predictive science. The proposed Research Unit aims at filling this gap of knowledge by applying novel experimental and analytical approaches in one of the longest-running biodiversity experiments in the world: the Jena Experiment. The central aim of the Research Unit is to uncover the mechanisms that determine BEF relationships in the short- and in the long-term. Increasing BEF relationships with time in long-term experiments do not only call for a paradigm shift in the appreciation of the relevance of biodiversity change, they likely are key to understanding the mechanisms of BEF relationships in general. The subprojects of the proposed Research Unit fall into two tightly linked main categories with two research areas each that aim at exploring variation in community assembly processes and resulting differences in biotic interactions as determinants of the long-term BEF relationship. Subprojects under âMicrobial community assemblyâ and âAssembly and functions of animal communitiesâ mostly focus on plant diversity effects on the assembly of communities and their feedback effects on biotic interactions and ecosystem functions. Subprojects under âMediators of plant-biotic interactionsâ and âIntraspecific diversity and micro-evolutionary changesâ mostly focus on plant diversity effects on plant trait expression and micro-evolutionary adaptation, and subsequent feedback effects on biotic interactions and ecosystem functions. This unification of evolutionary and ecosystem processes requires collaboration across the proposed subprojects in targeted plant and soil history experiments using cutting-edge technology and will produce significant synergies and novel mechanistic insights into BEF relationships. The Research Unit of the Jena Experiment is uniquely positioned in this context by taking an interdisciplinary and integrative approach to capture whole-ecosystem responses to changes in biodiversity and to advance a vibrant research field
Coherent neutrino-nucleus scattering detection with a CsI[Na] scintillator at the SNS spallation source
Consumer-resource body-size relationships in natural food webs
It has been suggested that differences in body size between consumer and resource species may have important implications for interaction strengths, population dynamics, and eventually food web structure, function, and evolution. Still, the general distribution of consumerâresource body-size ratios in real ecosystems, and whether they vary systematically among habitats or broad taxonomic groups, is poorly understood. Using a unique global database on consumer and resource body sizes, we show that the mean body-size ratios of aquatic herbivorous and detritivorous consumers are several orders of magnitude larger than those of carnivorous predators. Carnivorous predatorâprey body-size ratios vary across different habitats and predator and prey types (invertebrates, ectotherm, and endotherm vertebrates). Predatorâprey body-size ratios are on average significantly higher (1) in freshwater habitats than in marine or terrestrial habitats, (2) for vertebrate than for invertebrate predators, and (3) for invertebrate than for ectotherm vertebrate prey. If recent studies that relate body-size ratios to interaction strengths are general, our results suggest that mean consumerâresource interaction strengths may vary systematically across different habitat categories and consumer types
Body sizes of consumers and their resources
Trophic informationâwho eats whomâand species' body sizes are two of the most basic descriptions necessary to understand community structure as well as ecological and evolutionary dynamics. Consumerâresource body size ratios between predators and their prey, and parasitoids and their hosts, have recently gained increasing attention due to their important implications for species' interaction strengths and dynamical population stability. This data set documents body sizes of consumers and their resources. We gathered body size data for the food webs of Skipwith Pond, a parasitoid community of grass-feeding chalcid wasps in British grasslands; the pelagic community of the Benguela system, a source web based on broom in the United Kingdom; Broadstone Stream, UK; the Grand Cariçaie marsh at Lake NeuchĂątel, Switzerland; Tuesday Lake, USA; alpine lakes in the Sierra Nevada of California; Mill Stream, UK; and the eastern Weddell Sea Shelf, Antarctica. Further consumerâresource body size data are included for planktonic predators, predatory nematodes, parasitoids, marine fish predators, freshwater invertebrates, Australian terrestrial consumers, and aphid parasitoids. Containing 16 807 records, this is the largest data set ever compiled for body sizes of consumers and their resources. In addition to body sizes, the data set includes information on consumer and resource taxonomy, the geographic location of the study, the habitat studied, the type of the feeding interaction (e.g., predacious, parasitic) and the metabolic categories of the species (e.g., invertebrate, ectotherm vertebrate). The present data set was gathered with the intent to stimulate research on effects of consumerâresource body size patterns on food-web structure, interaction-strength distributions, population dynamics, and community stability. The use of a common data set may facilitate cross-study comparisons and understanding of the relationships between different scientific approaches and models
Data Paper. Data Paper
<h2>File List</h2><blockquote>
<p>Data file, original</p>
<blockquote>
<p>Data file is ASCII text, tab delimited. No compression schemes were used. Data set consists of 16,863 records, not including header row. </p>
<p><a href="bodysizes.txt">bodysizes.txt</a></p>
</blockquote>
<p>Data file, revision 1</p>
<blockquote>
<p><a href="bodysizes_2008.txt">bodysizes_2008.txt</a></p>
<p>Updated body size data for the food webs of Mill Stream and Skipwih Pond. Three additional predatorâprey links were added to the Skipwith Pond data. All other food web data remain unchanged. The new database now contains 16,866 rows and the sum over the data in the column "Consumer/resource body mass ratio" now equals 2.47388Â ĂÂ 10<sup>20</sup>. </p>
</blockquote>
</blockquote>
<div>
<hr>
</div><h2>Description</h2><blockquote>
<p>Trophic information â who eats whom â and speciesâ body sizes are two of the most basic descriptions necessary to understand community structure as well as ecological and evolutionary dynamics. Consumer-resource body size ratios between predators and their prey, and parasitoids and their hosts, have recently gained increasing attention due to their important implications for speciesâ interaction strengths and dynamical population stability. This data set documents body sizes of consumers and their resources. We gathered body size data for the food webs of Skipwith Pond, a parasitoid community of grass-feeding chalcid wasps in British grasslands; the pelagic community of the Benguela system, a source web based on broom in the United Kingdom; Broadstone Stream, UK; the Grand Cariçaie marsh at Lake NeuchĂątel, Switzerland; Tuesday Lake, USA; alpine lakes in the Sierra Nevada of California; Mill Stream, UK; and the eastern Weddell Sea Shelf, Antarctica. Further consumerâresource body size data are included for planktonic predators, predatory nematodes, parasitoids, marine fish predators, freshwater invertebrates, Australian terrestrial consumers, and aphid parasitoids. Containing 16,863 records, this is the largest data set ever compiled for body sizes of consumers and their resources. In addition to body sizes, the data set includes information on consumer and resource taxonomy, the geographic location of the study, the habitat studied, the type of the feeding interaction (e.g., predacious, parasitic) and the metabolic categories of the species (e.g., invertebrate, ectotherm vertebrate). The present data set was gathered with intent to stimulate research on effects of consumerâresource body size patterns on food-web structure, interaction-strength distributions, population dynamics, and community stability. The use of a common data set may facilitate cross-study comparisons and understanding of the relationships between different scientific approaches and models.</p>
<p><i>Key words: allometry; body length; body mass; body size ratio; food webs; parasitoidâhost; predation; predatorâprey</i>.</p>
</blockquote
Advancing the Landscape of Multimessenger Science in the Next Decade
Engel K, Lewis T, Muzio MS, et al. Advancing the Landscape of Multimessenger Science in the Next Decade. arXiv:2203.10074. 2022.The last decade has brought about a profound transformation in multimessenger
science. Ten years ago, facilities had been built or were under construction
that would eventually discover the nature of objects in our universe could be
detected through multiple messengers. Nonetheless, multimessenger science was
hardly more than a dream. The rewards for our foresight were finally realized
through IceCube's discovery of the diffuse astrophysical neutrino flux, the
first observation of gravitational waves by LIGO, and the first joint
detections in gravitational waves and photons and in neutrinos and photons.
Today we live in the dawn of the multimessenger era. The successes of the
multimessenger campaigns of the last decade have pushed multimessenger science
to the forefront of priority science areas in both the particle physics and the
astrophysics communities. Multimessenger science provides new methods of
testing fundamental theories about the nature of matter and energy,
particularly in conditions that are not reproducible on Earth. This white paper
will present the science and facilities that will provide opportunities for the
particle physics community renew its commitment and maintain its leadership in
multimessenger science