Nine publications showing REE data in groundwaters and river water were examined to understand the general condition of terrestrial where a negative Ce anomaly develops. It was found that only appeared when Fe, Mn dissolved organic carbon (DOC) concentrations low (Fe < 5 × 10-5 mol/L DOC 10 mg/L). Assuming Ce3+ Fe2+ limited by formation cerianite ferrihydrite, respective redox potential (Eh) calculated from each concentrations. For sets displaying anomalies, Ehs (cEhs) showed 1:1...

ABSTRACT Nitrogen compounds often serve as crucial electron donors and acceptors in microbial energy metabolism, playing a key role biogeochemical cycles. The energetic favorability of nitrogen oxidation–reduction (redox) reactions, driven by the thermodynamic properties these compounds, may have shaped evolution though extent their influence remains unclear. This study quantitatively evaluated similarity between energetically superior identified from 988 theoretically plausible...

Observational evidence supports the presence of methane (CH4) in martian atmosphere on order parts per billion by volume (ppbv). Here, we assess whether aerobic methanotrophy is a potentially viable metabolism upper regolith, calculating metabolic energy gain rates under assumed conditions surface temperature, pressure, and atmospheric composition. Using kinetic parameters for 19 terrestrial methanotrophic strains, show that even imposed low temperature pressure extremes (180-280 K 6-11...

Abstract Chemotrophic microorganisms synthesise biomass by utilising energy obtained from a set of chemical reactions that convert resources to by‐products, forming catabolic interactions. The amount per reaction decreases with the abundance by‐product named as ‘abundant resource premium’. Consider two species, Species 1 and 2, obtains converts A B. 2 then utilises B its resource, extracting C. Thus, presence reduces B, which improves fitness increasing acquisition We discuss population...

Possible chemotrophic metabolism at a site of interest is controlled not only by the catabolic energy expressed as Gibbs reaction (ΔrG) but also kinetic constraints due to availability electron acceptors and donors. We introduced graphical stochastic approaches for determining ΔrG threshold required support microbial population with specific strategy under constraints. Invasibility an indicator present reproductive ability was evaluated simultaneously calculating catalytic rate. For example,...

To harvest energy from chemical reactions, microbes engage in diverse catabolic interactions that drive material cycles the environment. Here, we consider a simple mathematical model for cycling reactions between alternative forms of an element (A and Ae), where reaction 1 converts A to Ae 2 A. There are two types microbes: type harness 1, 2. Each receives its own resources other provides with by-products as resources. Analyses show each increases steady-state abundance presence type. The...

The concentration of Fe in stream water and groundwater was measured monthly during a whole year. study fields were Ozenuma lake Senjougahara peatland, which snow covers for more than 5 months winter. Iron increased snow-covered thaw seasons with the synchronized decrease Eh pH both groundwater. In seasons, it is hypothesized that supply melt and/or coverage ice layers this period could cause development an anaerobic zone underlying soil. This suggests change amount snowfall or length season...

In traditional population models of microbial ecology, there are two central players: producers and consumers (including decomposers that depend on organic carbon). Producers support surface ecosystems by generating adenosine triphosphate (ATP) from sunlight, part which is used to build new biomass carbon dioxide. contrast, the productivity subsurface with a limited supply sunlight must rely bacteria archaea able generate ATP solely chemical or electric energy fix inorganic carbon. These...

The objective of this study is to identify a procedure for determining sample size allocation food radiation inspections more than one item minimize the potential risk consumers internal exposure. We consider simplified case monitoring and safety inspection in which manager required monitor two items, milk spinach, contaminated area. Three protocols with different allocations were assessed by simulating random sampling spinach conceptual site. Distributions 131 I radiocesium concentrations...

Microbial life in an ecosystem with low energy supply has been considered to employ two utilization strategies. The first is conservation at individual level, while the second use optimization response availability of resources. Here, using oxidation-reduction (redox) reaction network model where microbial metabolic pathways are established through multiple species-level competition and cooperation within a redox network, we hypothesize that ecosystems can move forward increase efficiency,...

Marine aggregates are one of the main contributors to carbon sequestration in deep sea through gravitational settling biogenic particles formed from photosynthetic products phytoplankton. The formation large due aggregation processes has been focus studies past, but recent findings on spatio-temporal distribution suggests that fragmentation plays an important role aggregate dynamics. Here, we assessed yield strength derived natural planktonic communities order analyze cohesive bond and...

<title>Abstract</title> Establishing a sustainable life-support system for space exploration is challenging due to the vast distances, costs, and differing environments from Earth. Using insights Biosphere 2 experiment, we introduced "Ecosphere" "Biosealed" systems in custom containers replicate Earth's ecosystems, suggesting feasible migration through transplanting Earth-like biomes. Over four years, gained deeper into these enclosed ecosystems. Moisture deficiency was major obstacle plant...

Abstract Nitrogen species often serve as crucial electron donors or acceptors in microbial catabolism, enabling the synthesis of adenosine triphosphate (ATP). Although theoretically any nitrogen redox reactions could be an energy source, it remains unclear why specific are predominantly utilized. This study evaluates energetically superior from 988 plausible combinations involving 11 species, oxygen gas, hydrogen ion, and water. Our analysis similarity between this model-based network actual...

Establishing a sustainable life-support system for space exploration is formidable challenge due to the vast distances, high costs, and environmental differences from Earth. Building upon lessons Biosphere 2 experiment, we introduce novel "Ecosphere" "Biosealed" systems, self-sustaining ecosystems within customizable, enclosed containers. These systems incorporate terrestrial groundwater layers, offering potential model transplanting Earth-like biomes extraterrestrial environments. Over 4...

Abstract The Japan Ministry of Health, Labour and Welfare (MHLW) has published instructions for radiological protection against food after the Fukushima Daiichi nuclear power plant accident in 2011. Following instructions, export consumption items identified as being contaminated were restricted a certain period. We assessed validity imposed restriction periods two representative vegetables (spinach cabbage) grown Prefecture from perspectives: effectiveness reducing dietary dose economic...