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Plants and cyanobacteria use the chlorophylls embedded in their photosystems to absorb photons and perform charge separation, the first step of converting solar energy to chemical energy. While oxygenic photosynthesis is primarily based on chlorophyll a photochemistry, which is powered by red light, a few cyanobacterial species can harness less energetic photons when growing in far-red light. Acclimatization to far-red light involves the incorporation of a small number of molecules of red-shifted chlorophyll f in the photosystems, whereas the most abundant pigment remains chlorophyll a. Due to its different energetics, chlorophyll f is expected to alter the excited-state dynamics of the photosynthetic units and, ultimately, their performances. Here we combined time-resolved fluorescence measurements on intact cells and isolated complexes to show that chlorophyll f insertion slows down the overall energy trapping in both photosystems. While this marginally affects the efficiency of photosystem I, it substantially decreases that of photosystem II. Nevertheless, we show that despite the lower energy output, the insertion of red-shifted chlorophylls in the photosystems remains advantageous in environments that are enriched in far-red light and therefore represents a viable strategy for extending the photosynthetically active spectrum in other organisms, including plants. However, careful design of the new photosynthetic units will be required to preserve their efficiency.

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.

In this study, the energy, exergy, exergoeconomic and exergoenvironmental (4E) analyses of a cogeneration system that combines photovoltaic thermal panels (PV/T), evacuated tube solar collectors, an organic Rankine cycle (ORC) and energy storage systems are performed. The cogeneration model is built to meet the load demand of independent houses in remote areas and avoids excessive consumption of traditional energy and environmental pollution. Here, the exergoenvironmental analysis adopts the Eco-indicator-99 method and the all life cycle assessment method is used to calculate the environmental impact of each component. Two comparative studies are conducted to the 4E analyses. The first one compares the comprehensive performance of the battery storage and hydrogen production for energy storage. The results indicate that the cogeneration system using both batteries and hydrogen production for energy storage has the best overall performance. According the exergoeconomic and exergoenvironmental analyses, its environmental impact is 23.6% lower than the cogeneration system using batteries alone and the PV/T can be fully utilized. In addition, the total cost rate is 6.2% lower than the cogeneration system using hydrogen production alone. The second case investigates the effect of adding the evacuated tube solar collectors between the PV/T and ORC on the cogeneration system. The analysis results demonstrate that the evacuated tube solar collectors can increase the heat source temperature of the ORC to increase the power generation of the ORC by 37.14%; however, the total cost rate of the cogeneration system increases by 3.7% and the environmental impact rate increases by 19.8%.

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.

The influence of two strains of Trichoderma (T. harzianum strain T22 and T. atroviride strain P1) on the growth of lettuce plants (Lactuca sativa L.) irrigated with As-contaminated water, and their effect on the uptake and accumulation of the contaminant in the plant roots and leaves, were studied. Accumulation of this non-essential element occurred mainly into the root system and reduced both biomass development and net photosynthesis rate (while altering the plant P status). Plant growth-promoting fungi (PGPF) of both Trichoderma species alleviated, at least in part, the phytotoxicity of As, essentially by decreasing its accumulation in the tissues and enhancing plant growth, P status and net photosynthesis rate. Our results indicate that inoculation of lettuce with selected Trichoderma strains may be helpful, beside the classical biocontrol application, in alleviating abiotic stresses such as that caused by irrigation with As-contaminated water, and in reducing the concentration of this metalloid in the edible part of the plant.

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