Acute Multiple Organ Failure in Adult Mice Deleted for the Developmental Regulator Wt1

There is much interest in the mechanisms that regulate adult tissue homeostasis and their relationship to processes governing foetal development. Mice deleted for the Wilms' tumour gene, Wt1, lack kidneys, gonads, and spleen and die at mid-gestation due to defective coronary vasculature. Wt1 is vital for maintaining the mesenchymal–epithelial balance in these tissues and is required for the epithelial-to-mesenchyme transition (EMT) that generates coronary vascular progenitors. Although Wt1 is only expressed in rare cell populations in adults including glomerular podocytes, 1% of bone marrow cells, and mesothelium, we hypothesised that this might be important for homeostasis of adult tissues; hence, we deleted the gene ubiquitously in young and adult mice. Within just a few days, the mice suffered glomerulosclerosis, atrophy of the exocrine pancreas and spleen, severe reduction in bone and fat, and failure of erythropoiesis. FACS and culture experiments showed that Wt1 has an intrinsic role in both haematopoietic and mesenchymal stem cell lineages and suggest that defects within these contribute to the phenotypes we observe. We propose that glomerulosclerosis arises in part through down regulation of nephrin, a known Wt1 target gene. Protein profiling in mutant serum showed that there was no systemic inflammatory or nutritional response in the mutant mice. However, there was a dramatic reduction in circulating IGF-1 levels, which is likely to contribute to the bone and fat phenotypes. The reduction of IGF-1 did not result from a decrease in circulating GH, and there is no apparent pathology of the pituitary and adrenal glands. These findings 1) suggest that Wt1 is a major regulator of the homeostasis of some adult tissues, through both local and systemic actions; 2) highlight the differences between foetal and adult tissue regulation; 3) point to the importance of adult mesenchyme in tissue turnover

Implications of diversification strategies in the European natural gas market for the German energy system

The energy system is facing changes across Europe, motivated by CO2 emission reduction targets and driven by the expansion of renewable energy sources (RES). Germany is carrying out efforts to reshape its future energy system to be mainly based on RES. Nonetheless, flexible generation capacities like natural gas (NG) power plants will still be needed in the coming decades. Recent developments in the NG market have been characterised by uncertainties on the supply side as plans have been put forth for new pipelines to facilitate Russian or Caspian NG towards Europe as well as increasing volumes of liquefied natural gas entering the market. This paper aims to show the interdependence between infrastructure developments and primary NG demand in the German energy system. The authors analyse impacts for the German ‘Energiewende’ on a time horizon from 2010 to 2050. Coupling a European NG model with a German energy system model, we develop six scenarios regarding climate policy in Germany and European diversification strategies in infrastructure expansion. The results show, that NG prices influence sectoral changes especially in the residential sector. Further strategies to reduce CO2 emissions in the entire energy system should also consider NG as part of the solution

Technical potential of salt caverns for hydrogen storage in Europe

The role of hydrogen in a future energy system with a high share of variable renewable energy sources (VRES) is regarded as crucial in order to balance fluctuations in electricity generation. These fluctuations can be compensated for by flexibility measures such as the expansion of transmission, flexible generation, larger back-up capacity and storage. Salt cavern storage is the most promising technology due to its large storage capacity, followed by pumped hydro storage. For the underground storage of chemical energy carriers such as hydrogen, salt caverns offer the most promising option owing to their low investment cost, high sealing potential and low cushion gas requirement. This paper provides a suitability assessment of European subsurface salt structures in terms of size, land eligibility and storage capacity. Two distinct cavern volumes of 500,000 m3 and 750,000 m3 are considered, with preference being given for salt caverns over bedded salt deposits and salt domes. The storage capacities of individual caverns are estimated on the basis of thermodynamic considerations based on site-specific data. The results are analyzed using three different scenarios: onshore and offshore salt caverns, only onshore salt caverns and only onshore caverns within 50 km of the shore. The overall technical storage potential across Europe is estimated at 84.8 PWhH2, 27% of which constitutes only onshore locations. Furthermore, this capacity decreases to 7.3 PWhH2 with a limitation of 50 km distance from shore. In all cases, Germany has the highest technical storage potential, with a value of 9.4 PWhH2, located onshore only in salt domes in the north of the country. Moreover, Norway has 7.5 PWhH2 of storage potential for offshore caverns, which are all located in the subsurface of the North Sea Basin