A novel role for the Hox gene Deformed in the control of a motor system required for feeding in Drosophila

Animals interact with their environment based on stereotypical movement patterns, such as those performed during running, breathing or feeding. Hox regulatory genes had been known to be essential for establishing coordinated movements, but the molecular underpinnings of feeding behaviour were not well understood. Using Drosophila melanogaster as a model system, the present work demonstrates that a specific Hox gene, Deformed, controls the establishment of a motor unit in the fly's head during embryonic development. This unit comprises a muscle and a set of stimulating neurons and enables feeding-related movements. The loss of functional Deformed caused severe defects in the formation of the feeding motor unit and subsequently led to death. Furthermore, inactivation of Deformed at the end of embryogenesis, once the motor unit was successfully assembled, uncovered a novel role for Deformed in maintaining the functionality and integrity of the motor unit later in life. Finally, perturbations in motor behaviour were pinned to the role of Deformed in the control of molecules essential for synapse stability at the junctions between neurons and muscles. One of the identified direct targets of Deformed is Ankyrin, a molecule previously shown to be involved in neurodegenerative diseases such as Alzheimer's. Hence, the results presented here suggest that Hox genes might have a neuroprotective function and once this function is gone, the neurons degenerate, a hypothesis that will be of interest to study in the future. Interestingly, Deformed is co-expressed in muscles and neurons forming the functional feeding motor unit, pointing at its role as a master regulator of feeding behaviour. In support of this hypothesis, Deformed was shown to act as one of the negative upstream regulators of Connectin, a molecule essentially required for the correct matching between the two partners. Is the function of Hox transcription factors in the establishment of feeding motor units conserved across the animal phylogeny? This work uncovered a fly neural regulatory element of Deformed, which contains highly conserved Hox-binding sites, to be active in neurons located within the hindbrain of the vertebrate fish model Oryzias latipes, suggesting that the transcriptional network controlling the assembly and function of the feeding unit in fish and flies is conserved

Bioeconomic fiction between narrative dynamics and a fixed imaginary: evidence from India and Germany

Bioeconomic ideas and visions have received increasing attention from scientists and policy makers to address socioecological challenges. However, the role of imagined futures in the design of bioeconomic innovations and transitions has hitherto been widely neglected. In this study, we therefore explore the role of imaginaries of the future to understand how they shape bioeconomic innovations and transitions. We thereby build on insights from economic sociology and compare two distinct case studies from Germany and India. Based on our results, we inductively develop an analytic model that describes the co-constitution of imaginaries, fictional expectations, narratives, and innovation dynamics. Our results show that narrative dynamics are caused by irritations in the political and discursive landscape; these irritations prompt economic actors to stabilize, adapt, or reject their own bioeconomic conceptions, while the underlying imaginary of a technological fix remains fixed. We discuss this reductionist imaginary and instead plead for an imaginary of a socioecological fix that reintertwines technologies with their underlying societal, cultural, and ecological factors. We conclude that this will support sustainability scholars and policy makers in remaining vigilant against premature mental and institutional lock-ins that could lead to a colonization of the future with severe negative implications for society's ability to mitigate and adapt to global environmental change in the future

Identification of base erosion and profit shifting using tax evasion rate

Multinational enterprises (MNEs) use different methods and structures for base erosion and profit shifting (BEPS) to optimize the tax liability of the group. It is of great interest to the relevant countries to be able to identify such practices and react with appropriate measures. The objective of this paper is to verify whether selected MNEs engaged in the digital economy tend to shift profits from the Czech Republic to jurisdictions with lower taxation using the tax evasion rate (TER) indicator and the transactional net margin method (TNNM). Since the TER method has not been tested yet, this paper also aims to demonstrate its application on real world data and to evaluate its usability. On a sample of five MNEs, the analysis showed a potential tendency to shift profits within Europe for four MNEs (Amazon, Apple, Google and Uber) and a potential tendency to shift profits specifically from the Czech Republic for one MNE (Amazon). The analysis shows that TER is suitable as a preliminary indication of possible risks, rather than their exact quantification

Life cycle assessment (LCA) of a battery home storage system based on primary data

While the market for battery home storage systems (HSS) is growing rapidly, there are still few well-modelled life cycle assessment (LCA) studies available for quantifying their potential environmental benefits and impacts. Existing studies mainly rely on data for electric vehicles and often lack a thorough modelling approach, especially regarding the peripheral components. This paper presents a full cradle to grave LCA of a Lithium iron phosphate (LFP) battery HSS based on primary data obtained by part-to-part dismantling of an existing commercial system with a focus on the impact of the peripheral components. Additionally, alternative battery chemistries (Sodium ion battery (SIB) and two lithium nickel manganese cobalt oxides, (NMC811, and NMC622) are investigated under the consideration of the same periphery. This approach allows a comprehensive com parison between present and emerging cell chemistries that can be potentially considered for an HSS. The total greenhouse gas emissions of the HSS are 84 g CO2eq/KWh of electricity delivered over its lifetime in a residential PV application, or 31 g CO2eq/KWh over lifetime when excluding the use-phase impact. The peripheral components contribute between 37% and 85% to the total gross manufacturing impacts of the HSS, depending on the considered cell chemistry and the impact category. Especially the inverter plays an important role, and its impacts are significantly higher than those obtained when using the standard ecoinvent dataset, indicating that the contribution of power electronics might often be underestimated when using this dataset. In terms of cell chemistries, the considered SIB turns out to be not yet competitive with LIB chemistries due to its lower energy density and lifetime, but might become so when reaching similar lifetimes

Nutrient uptake and benthic regeneration in Danube Delta Lakes

We investigated the nutrient uptake capacity of three lakes (Uzlina, Matita and Rosu) within the Danube Delta during high water level in June and low water level in September 1999. Special emphasis was placed on nutrient cycling at the sediment-water interface and on the self-purification capacity of the lakes in the Danube Delta. In order to estimate the nutrient uptake of selected lakes we present in this paper the results of water analyses, benthic flux chamber experiments and deck incubation experiments of 15N-labeled sediment cores at the inflow and the outlet of the lakes. The external input of dissolved inorganic nitrogen and silica into the lakes decreases with increasing distance to the main Danube branches whereas the total dissolved phosphorus input is independent of the hydrological distance to the main branches. The nutrient loading is highest in the inflow channels, and decreases towards the outflow of the lakes. In June, the uptake of NO3 −, TDP and Si(OH)4 in the lakes was higher than in September. In contrast, NH4 + uptake was more intense in September, when benthic release was more intense as well. On average, about 76% of the external plus internal nitrogen and phosphorus input into the lakes was taken up by macrophytes and phytoplankton during the growing season, whereas the uptake of external nutrient input amounted to about 43%. The benthic release of ammonia and silica increases from June to September and indicates, that part of the nutrients taken up during the growing season might be released during winter. We estimate the net impact of the Delta on the nutrient reduction of the Danube during the growing season is about 4.3%, assuming 10% of the Danube water is flowing through the Delt

Life cycle assessment (LCA) of a battery home storage system based on primary data

While the market for battery home storage systems (HSS) is growing rapidly, there are still few well-modelled life cycle assessment (LCA) studies available for quantifying their potential environmental benefits and impacts. Existing studies mainly rely on data for electric vehicles and often lack a thorough modelling approach, especially regarding the peripheral components. This paper presents a full cradle to grave LCA of a Lithium iron phosphate (LFP) battery HSS based on primary data obtained by part-to-part dismantling of an existing commercial system with a focus on the impact of the peripheral components. Additionally, alternative battery chemistries (Sodium ion battery (SIB) and two lithium nickel manganese cobalt oxides, (NMC811,and NMC622) are investigated under the consideration of the same periphery. This approach allows a comprehensive comparison between present and emerging cell chemistries that can be potentially considered for an HSS. The total greenhouse gas emissions of the HSS are 84 g CO2eq/KWh of electricity delivered over its lifetime in a residential PV application, or 31 g CO2eq/KWh over lifetime when excluding the use-phase impact. The peripheral components contribute between 37% and 85% to the total gross manufacturing impacts of the HSS, depending on the considered cell chemistry and the impact category. Especially the inverter plays an important role, and its impacts are significantly higher than those obtained when using the standard ecoinvent dataset, indicating that the contribution of power electronics might often be underestimated when using this dataset. In terms of cell chemistries, the considered SIB turns out to be not yet competitive with LIB chemistries due to its lower energy density and lifetime, but might become so when reaching similar lifetimes

Regulation of benthic oxygen fluxes in permeable sediments of the coastal ocean

Large areas of the oceanic shelf are composed of sandy sediments through which reactive solutes are transported via porewater advection fueling active microbial communities. The advective oxygen transport in permeable sands of the North Sea was investigated under in situ conditions using a new benthic observatory to assess the dynamic interaction of hydrodynamics, sediment morphodynamics, and oxygen penetration depth. During 16 deployments, concurrent measurement of current velocity, sediment topography, and porewater oxygen concentration were carried out. In all cases the oxyclines were found at depths of 1–6 cm, correlating with the topography of stationary and migrating bedforms (ripples). Different conditions in terms of bottom water currents and bedform migration led to fluctuating oxygen penetration depths and, hence, highly variable redox conditions in up to 2.5 cm thick layers beneath the surface. Volumetric oxygen consumption rates of surface sediments were measured on board in flow-through reactors. Bedform migration was found to reduce consumption rates by up to 50%, presumably caused by the washout of organic carbon that is otherwise trapped in the pore space of the sediment. Based on the observations we found oxygen penetration depths to be largely controlled by oxygen consumption rates, grain size, and current velocity. These controlling variables are summarized by an adapted Damköhler number which allows for prediction of oxygen penetretion depths based on a simple scaling law. By integrating the oxygen consumption rates over the oxygen penetration depth, oxygen fluxes of 8–34 mmol m−2 d−1 were estimate

Natural selection supports escape from concerted evolution of a recently duplicated CEACAM1 paralog in the ruminant CEA gene family

Concerted evolution is often observed in multigene families such as the CEA gene family. As a result, sequence similarity of paralogous genes is significantly higher than expected from their evolutionary distance. Gene conversion, a "copy paste" DNA repair mechanism that transfers sequences from one gene to another and homologous recombination are drivers of concerted evolution. Nevertheless, some gene family members escape concerted evolution and acquire sufficient sequence differences that orthologous genes can be assigned in descendant species. Reasons why some gene family members can escape while others are captured by concerted evolution are poorly understood. By analyzing the entire CEA gene family in cattle (Bos taurus) we identified a member (CEACAM32) that was created by gene duplication and cooption of a unique transmembrane domain exon in the most recent ancestor of ruminants. CEACAM32 shows a unique, testis-specific expression pattern. Phylogenetic analysis indicated that CEACAM32 is not involved in concerted evolution of CEACAM1 paralogs in ruminants. However, analysis of gene conversion events revealed that CEACAM32 is subject to gene conversion but remarkably, these events are found in the leader exon and intron sequences but not in exons coding for the Ig-like domains. These findings suggest that natural selection hinders gene conversion affecting protein sequences of the mature protein and thereby support escape of CEACAM32 from concerted evolution