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Alcohol is a well-known risk factor for hepatocellular carcinoma. Autophagy plays a dual role in liver cancer, as it suppresses tumor initiation and promotes tumor progression. Transcription factor EB (TFEB) is a master regulator of lysosomal biogenesis and autophagy, which is impaired in alcohol-related liver disease. However, the role of TFEB in alcohol-associated liver carcinogenesis is unknown. Liver-specific Tfeb knockout (KO) mice and their matched wild-type (WT) littermates were injected with the carcinogen diethylnitrosamine (DEN), followed by chronic ethanol feeding. The numbers of both total and larger tumors increased significantly in DEN-treated mice fed ethanol diet than in mice fed control diet. Although the number of tumors was not different between WT and L-Tfeb KO mice fed either control or ethanol diet, the number of larger tumors was less in L-Tfeb KO mice than in WT mice. No differences were observed in liver injury, steatosis, inflammation, ductular reaction, fibrosis, and tumor cell proliferation in DEN-treated mice fed ethanol. However, the levels of glypican 3, a marker of malignant hepatocellular carcinoma, markedly decreased in DEN-treated L-Tfeb KO mice fed ethanol in comparison to the WT mice. These findings indicate that chronic ethanol feeding promotes DEN-initiated liver tumor development, which is attenuated by genetic deletion of hepatic TFEB.

Abstract This paper presents the first study in the academic literature to explore the various stages in the formation of geothermal ES and their interactions between the biosphere and anthroposphere. This is achieved through the development of the first ES cascade model in the academic literature specific to geothermal ES, which integrates the four main stages of co-production: value attribution, mobilisation of ES potential, value appropriation, and commercialisation. In so doing, conceptual understanding of human-environment relationships and processes in the context of geothermal ES are deepened. Examples from the academic and grey literature demonstrate that realisation of the full spectrum of benefits from geothermal areas often demands the mobilisation of various forms of physical capital. Reaping the benefits of provisioning ES, such as heat and minerals, or formal recreational experiences, such as geothermal spas, necessitates human interventions. Opportunities of likely value have to be attributed, with resources being mobilised in order to plan and research prospectivity, then benefits appropriated with a view to their commercialisation. Large-scale, industrial projects, especially geothermal power plants in high enthalpy fields, also constitute an overlap between anthropogenic and ecological systems, often leading to ES trade-offs, especially due to visual and noise impacts on the surroundings. Depending on the sociocultural context, multiple and conflicting value domains may be impacted by such ventures, justifying the adoption of a pluralist approach to valuation and use of integrated decision-support platforms to aid decision-makers.

Carotenoids are important photosynthetic pigments that play key roles in light harvesting and energy transfer, photoprotection, and in the folding, assembly, and stabilization of light-harvesting pigment-protein complexes. The genetically tractable purple phototrophic bacteria have been useful for investigating the biosynthesis and function of photosynthetic pigments and cofactors, including carotenoids. Here, we give an overview of the roles of carotenoids in photosynthesis and of their biosynthesis, focusing on the extensively studied purple bacterium Rhodobacter sphaeroides as a model organism. We provide detailed procedures for manipulating carotenoid biosynthesis, and for the preparation and analysis of the light-harvesting and photosynthetic reaction center complexes that bind them. Using appropriate examples from the literature, we discuss how such approaches have enhanced our understanding of the biosynthesis of carotenoids and the photosynthesis-related functions of these fascinating molecules.

Abstract The performances of a commercial Mg/Al hydrotalcite (Pural© MG76) in biodiesel production have been tested in an autoclave and in a continuous packed bed reactor. The obtained results have shown that calcined Mg/Al hydrotalcite (Pural© MG76) is a promising heterogeneous catalyst for biodiesel production because is sufficiently active, deactivates slowly and can easily be regenerated.

Variability of central European temperature and precipitation shows correlations with some major historical changes.

Abstract If geothermal resources are utilized excessively for electricity production, the reservoir can be temporarily (almost) depleted. Regeneration of an overutilized resource can take a long time. This paper presents a System Dynamics model for geothermal power plant expansion considering the dynamics of geothermal resources on a system’s level. The model consists of three main modules: resource dynamics, plant construction, and geothermal economics. Thereby, it captures the following dynamics: The geothermal field stock decreases due to utilization for electricity production and increases through natural recharging. Changes in geothermal stock, and thus in well production capacity, lead to additional well requirements to maintain electricity production levels. This influences the unit cost of electricity. To show the effect of geothermal resource dynamics on a national system’s level the model is applied to Iceland’s geothermal resources. Four main scenarios are simulated and compared based on the level of resource utilization, assuming high and low demand growth (i.e. 2% and 4.4%), and whether geothermal resource dynamics are incorporated or not. Sensitivity analysis is performed with respect to well capital cost and natural recharging rates for geothermal fields. The findings indicate that geothermal resource dynamics significantly increase costs because of the well drilling activities that are required to maintain production.

Abstract Kenya's current electricity production is mainly relying on hydro and geothermal resources. Both of these resources are subject to complex dynamics that affect their sustainable utilization. Neither the current power expansion plan for Kenya, nor the existing electricity supply models address such effects. The research question in this paper is: What are the implications of hydro and geothermal resource dynamics for short- and long-term (sustainable) electricity system planning in Kenya? To answer this question a bottom-up system dynamics model representing the most prevalent technologies of Kenya's future electricity system, including the dynamics of geothermal and hydro resource utilization, is developed. The stock-flow system dynamics modelling allows to capture the resources characteristics and the link to electricity production. Due to the stock-like nature of geothermal resource, excessive utilization can lead to production capacity losses. In the case of hydro resources, climate change can reduce their availability significantly. A total of eight scenarios varying in demand size and consideration of resource dynamics are simulated and compared. The results indicate that when geothermal and hydro resource dynamics are considered, higher installed capacity will be required in the long-term to compensate production losses, which in turn leads to a higher electricity generation cost.