124 research outputs found
Molecular basis for the reproductive division of labour in a lower termite
<p>Abstract</p> <p>Background</p> <p>Polyphenism, the expression of different phenotypes with the same genetic background, is well known for social insects. The substantial physiological and morphological differences among the castes generally are the result of differential gene expression. In lower termites, workers are developmentally flexible to become neotenic replacement reproductives via a single moult after the death of the founding reproductives. Thus, both castes (neotenics and workers) are expected to differ mainly in the expression of genes linked to reproductive division of labour, which constitutes the fundamental basis of insect societies.</p> <p>Results</p> <p>Representational difference analysis of cDNAs was used to study differential gene expression between neotenics and workers in the drywood termite <it>Cryptotermes secundus </it>(Kalotermitidae). We identified and, at least partially cloned five novel genes that were highly expressed in female neotenics. Quantitative real-time PCR analysis of all five genes in different castes (neotenics, founding reproductives, winged sexuals and workers of both sexes) confirmed the differential expression patterns. In addition, the relative expression of these genes was determined in three body parts of female neotenics (head, thorax, and abdomen) using quantitative real-time PCR.</p> <p>Conclusion</p> <p>The identified genes could be involved in the control and regulation of reproductive division of labour. Interestingly, this study revealed an expression pattern partly similar to social Hymenoptera indicating both common and species-specific regulatory mechanisms in hemimetabolous and holometabolous social insects.</p
Learning to Cooperate and Communicate Over Imperfect Channels
Information exchange in multi-agent systems improves the cooperation among
agents, especially in partially observable settings. In the real world,
communication is often carried out over imperfect channels. This requires
agents to handle uncertainty due to potential information loss. In this paper,
we consider a cooperative multi-agent system where the agents act and exchange
information in a decentralized manner using a limited and unreliable channel.
To cope with such channel constraints, we propose a novel communication
approach based on independent Q-learning. Our method allows agents to
dynamically adapt how much information to share by sending messages of
different sizes, depending on their local observations and the channel's
properties. In addition to this message size selection, agents learn to encode
and decode messages to improve their jointly trained policies. We show that our
approach outperforms approaches without adaptive capabilities in a novel
cooperative digit-prediction environment and discuss its limitations in the
traffic junction environment
From remote to urbanized: dispersal of antibiotic-resistant bacteria under the aspect of anthropogenic influence
Antibiotic resistance is a growing global concern, but our understanding of the spread of resistant bacteria in remote regions remains limited. While some level of intrinsic resistance likely contributes to reduced susceptibility to antimicrobials in the environment, it is evident that human actions, particularly the (mis)use of antibiotics, play a significant role in shaping the environmental resistome, even in seemingly distant habitats like glacier ice sheets. Our research aims to bridge this knowledge gap by investigating the direct influence of human activities on the presence of antibiotic-resistant bacteria in various habitats. To achieve a comprehensive assessment of anthropogenic impact across diverse and seemingly isolated sampling sites, we developed an innovative approach utilizing Corine Land Cover data and heatmaps generated from sports activity trackers. This method allowed us to make meaningful comparisons across relatively pristine environments. Our findings indicate a noteworthy increase in culturable antibiotic-resistant bacteria with heightened human influence, as evidenced by our analysis of glacier, snow, and lake water samples. Notably, the most significant concentrations of antibiotic-resistant and multidrug-resistant microorganisms were discovered in two highly impacted sampling locations, namely the Tux Glacier and Gas Station Ellma
Relations between Effects and Structure of Small Bicyclic Molecules on the Complex Model System Saccharomyces cerevisiae
The development of compounds able to modify biological functions largely took advantage of parallel synthesis to generate a broad chemical variance of compounds to be tested for the desired effect(s). The budding yeast Saccharomyces cerevisiae is a model for pharmacological studies since a long time as it represents a relatively simple system to explore the relations among chemical variance and bioactivity. To identify relations between the chemical features of the molecules and their activity, we delved into the effects of a library of small compounds on the viability of a set of S. cerevisiae strains. Thanks to the high degree of chemical diversity of the tested compounds and to the measured effect on the yeast growth rate, we were able to scale-down the chemical library and to gain information on the most effective structures at the substituent level. Our results represent a valuable source for the selection, rational design, and optimization of bioactive compounds
TCT-500 Effect of Renal Denervation (RDN) in "Real World" Patients with trHTN Compared to Simplicity HTN-2 Trial. First Results of the Luebeck RDN Registry
Comparative patent analysis for the identification of global research trends for the case of battery storage, hydrogen and bioenergy
Patent documents provide knowledge about which countries are investing in certain technologies and make it possible to identify potential innovation trends. The aim of this article is to analyze trends in patenting that might result in innovations for three energy technologies: thermochemical conversion of biomass (Bioenergy), lithium-ion battery storage, and hydrogen production by alkaline water electrolysis. Based on different patent indicators, the most active countries are compared to provide insights into the global market position of a country, particularly Germany which is used as a reference here. In line with this, a freely available patent analysis software tool was developed directly using the European Patent Office database through their Open Patent Services. The results for named technologies show that patenting activity of Germany is low in comparison to other countries such as Japan, China, and the US. Whereas the position of Germany for batteries and hydrogen is comparable, bioenergy shows different results regarding the identified countries and the number of patents found. However, a broader context beyond patenting is suggested for consideration to make robust statements about particular technology trends. The presented tool and methodology in this study can serve as a blueprint for explorative assessments in any technological domain
Prospective assessment of energy technologies: a comprehensive approach for sustainability assessment
Background: A further increase in renewable energy supply is needed to substitute fossil fuels and combat climate change. Each energy source and respective technologies have specific techno-economic and environmental characteristics as well as social implications. This paper presents a comprehensive approach for prospective sustainability assessment of energy technologies developed within the Helmholtz Initiative “Energy System 2050” (ES2050).Methods: The “ES2050 approach” comprises environmental, economic, and social assessment. It includes established life cycle based economic and environmental indicators, and social indicators derived from a normative concept of sustainable development. The elaborated social indicators, i.e. patent growth rate, acceptance, and domestic value added, address three different socio-technical areas, i.e. innovation (patents), public perception (acceptance), and public welfare (value added).Results: The implementation of the “ES2050 approach” is presented exemplarily and different sustainability indicators and respective results are discussed based on three emerging technologies and corresponding case studies: (1) synthetic biofuels for mobility; (2) hydrogen from wind power for mobility; and (3) batteries for stationary energy storage. For synthetic biofuel, the environmental advantages over fossil gasoline are most apparent for the impact categories Climate Change and Ionizing Radiation—human health. Domestic value added accounts for 66% for synthetic biofuel compared to 13% for fossil gasoline. All hydrogen supply options can be considered to become near to economic competitiveness with fossil fuels in the long term. Survey participants regard Explosion Hazard as the most pressing concern about hydrogen fuel stations. For Li-ion batteries, the results for patent growth rate indicate that they enter their maturity phase.Conclusions: The “ES2050 approach” enables a consistent prospective sustainability assessment of (emerging) energy technologies, supporting technology developers, decision-makers in politics, industry, and society with knowledge for further evaluation, steering, and governance. The approach presented is considered rather a starting point than a blueprint for the comprehensive assessment of renewable energy technologies though, especially for the suggested social indicators, their significance and their embedding in context scenarios for prospective assessments
Towards QoE-Driven Optimization of Multi-Dimensional Content Streaming
Whereas adaptive video streaming for 2D video is well established and frequently used in streaming services, adaptation for emerging higher-dimensional content, such as point clouds, is still a research issue. Moreover, how to optimize resource usage in streaming services that support multiple content types of different dimensions and levels of interactivity has so far not been sufficiently studied. Learning-based approaches aim to optimize the streaming experience according to user needs. They predict quality metrics and try to find system parameters maximizing them given the current network conditions. With this paper, we show how to approach content and network adaption driven by Quality of Experience (QoE) for multi-dimensional content. We describe components required to create a system adapting multiple streams of different content types simultaneously, identify research gaps and propose potential next steps
Struktur und Entwicklung des Oberrheingrabens als europäischer Wirtschaftsstandort - Kurzfassung
In dieser Arbeit wird die ökonomische Situation des Oberrheingrabens anhand der Themenbereiche Beschäftigung und Arbeitslosigkeit, Forschung und Entwicklung, Wachstum und Produktivität und Unternehmensgründungen analysiert. Zudem werden die wichtigsten infrastrukturellen Rahmenbedingungen, die Bevölkerungsentwicklung und Unterschiede in der Besteuerung und in den Genehmigungsverfahren innerhalb des trinationalen Oberrheingrabens dargestellt. Darauf aufbauend wird das Potential und die mögliche Rolle der
Region als europäischer Wirtschaftsstandort diskutiert.
Die Untersuchung entstand in Zusammenarbeit zwischen dem Institut für angewandte Wirtschaftsforschung, IAW, in Tübingen, der Konjunkturforschung Basel AG, BAK, in Basel und
dem Zentrum für Europäische Wirtschaftsforschung, ZEW, in Mannheim. Dabei übernahm das IAW die Untersuchung der Bevölkerungsentwicklung, des Arbeitsmarktes, der Gewerbeflächen und des Wohnungsmarktes. Das BAK untersuchte das regionale Wachstum, die
Produktivitätsentwicklung und die nationalen Genehmigungsverfahren. Die Kapitel über die
Verkehrsinfrastruktur, die Besteuerung der Unternehmen, Forschung und Entwicklung und
Unternehmensgründungen wurden vom ZEW erstellt. Die Schlußfolgerungen wurden gemeinsam von den drei Instituten erarbeitet
- …