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For many of the world's fisheries, harvest control rules (HCRs) are the main tools for supporting decision-making. We previously clarified the optimal shape of the HCR to achieve multiple fisheries management objectives (maximising average catch, reducing variation in yields, and avoiding stock collapse) and ensure robustness to estimation errors in biomass by numerically estimating the optimal values of the 21 biological reference points (BRPs) comprised in the HCR. However, for actual management, a simple but comprehensive functional form to emulate the optimal HCR is desirable, as numerical HCR optimisation with many BRPs is time-consuming. Here, we introduced three objective utility functions (U1-U3) representing HCR performance for composite management objectives: mean-variance utility functions, where the performance indicator for variation in yields is the standard deviation (U1) or the annual average variance (U2) of yields, and the constant relative risk aversion utility function (U3). We derived two equations to emulate the optimal HCRs with three adjusting parameters corresponding to the management objectives and different magnitudes of estimation errors. These equations will help stakeholders discuss desired management strategies by showing expected catch and risk by adjusting the parameter values. Key words: bio-economics, fishery management objective, harvest control rule, management strategy evaluation, utility function, 1. Introduction To realise a sustainable society, wide-ranging problems need to be solved. In 2015, the United Nations adopted the Sustainable Development Goals (SDGs), comprising 17 goals and 169 targets, [...]

We show the following hold, unconditionally unless otherwise stated, relative to a random oracle: — There are NP search problems solvable by quantum polynomial-time (QPT) machines but not classical probabilistic polynomial-time (PPT) machines. — There exist functions that are one-way, and even collision resistant, against classical adversaries but are easily inverted quantumly. Similar counterexamples exist for digital signatures and CPA-secure public key encryption (the latter requiring the assumption of a classically CPA-secure encryption scheme). Interestingly, the counterexample does not necessarily extend to the case of other cryptographic objects such as PRGs. — There are unconditional publicly verifiable proofs of quantumness with the minimal rounds of interaction: for uniform adversaries, the proofs are non-interactive, whereas for non-uniform adversaries the proofs are two message public coin. — Our results do not appear to contradict the Aaronson-Ambanis conjecture. Assuming this conjecture, there exist publicly verifiable certifiable randomness, again with the minimal rounds of interaction. By replacing the random oracle with a concrete cryptographic hash function such as SHA2, we obtain plausible Minicrypt instantiations of the above results. Previous analogous results all required substantial structure, either in terms of highly structured oracles and/or algebraic assumptions in Cryptomania and beyond. [ABSTRACT FROM AUTHOR]

Conductive polymer, doped poly(3,4-ethylenedioxythiophene) (PEDOT) is a commonly employed material owing to its high conductivity, flexibility, and low-energy fabrication process. However, the broad dispersity poses challenges for understanding the conduction mechanism and designing molecules based on structure–conductivity relationships. To address this, we have focused on monodisperse oligomer conductors that provide detailed structural information owing to their crystallinity and structure control parameters involving the type, number, and sequence of monomer units, which enable the control of their electronic structures and physical properties. In this study, we investigate the effect of end groups, as another structure control parameter, on doped 3,4-ethylenedioxythiophene (EDOT) dimers, the simplest oligomers, by comparing methylthio and methylseleno groups. Substituting heavier chalcogens, from S to Se atoms, at the end groups effectively improves the electrical conductivity of doped EDOT oligomer conductors. This is due to the expansion of molecular orbitals and extension of the conjugate area of the donor, which strengthen the intermolecular interactions and bandwidth while weakening the effective Coulomb repulsion between conducting carriers. Additionally, Se-substituted end groups can induce a multiorbital system in the band structure, where the highest occupied molecular orbital (HOMO) and second HOMO (HOMO−1) bands contribute to electronic properties. Therefore, the electrical conductivities of Se-substituted oligomer salts at room temperature improve by one order of magnitude in relation to those of S-substituted oligomer salts. This approach offers guidance for designing conductors based on end groups, resulting in diverse crystal structures and electronic states that enhance conductivity. [ABSTRACT FROM AUTHOR]

Understanding the natural factors that influence diadromous fish communities in river ecosystems is crucial for effective biodiversity management. However, this remains an unexplored and challenging task. Here, the relationship between river morphology and diadromous fish communities within rivers was explored. We focused on river slope and estuary size, as these may constrain their upstream migration and affect the availability of important nursery grounds for some species. Using environmental DNA metabarcoding, we investigated the diadromous fish communities within 12 rivers of subtropical Yakushima Island, southern Japan, and compared the community differences among rivers with different river slopes and estuary sizes. Fewer diadromous fish species were detected in rivers with steeper slopes and smaller estuaries. Additionally, the community similarity was greater among rivers with analogous gradients and estuary sizes. These results indicate that river slopes exert a species-selective effect on diadromous fish communities by affecting their upstream migration and estuarine habitat availability, thereby playing a crucial role in shaping the composition of these communities within rivers. Conserving gentle-gradient rivers with large estuaries would be crucial for preserving the diversity of diadromous fish species, which play a crucial role in shaping biodiversity especially in rivers of subtropical and tropical oceanic islands. Diadromous fishes, which migrate between freshwater and marine habitats during their life cycle, are crucial components of riverine biodiversity. However, the factors that influence their composition within rivers remain unknown. Using environmental DNA metabarcoding, we showed that river slopes play a crucial role in shaping their composition within rivers by affecting their upstream migration and estuarine habitat availability. [ABSTRACT FROM AUTHOR]

Iron (Fe) is critical for plant growth. Under conditions of low Fe availability, rice plants induce genes involved in Fe uptake and utilization. Recently, we identified the iron-deficiency-responsive cis-acting elements IDE1 and IDE2, which are bound in a specific manner by IDE-binding factors 1 and 2 (IDEF1 and IDEF2, respectively). IDEF1 and IDEF2 regulate genes related to the Fe-deficiency response. In the present study, we examined the spatial expression patterns of IDEF1 and IDEF2 during the germination, vegetative, and seed-maturation stages by assessing their localization in IDEF1 and IDEF2 promoter–GUS transgenic rice lines. During germination, IDEF1 and IDEF2 were expressed in the endosperm and embryo. In hydroponic culture experiments, the expression patterns of IDEF1 and IDEF2 were similar under both Fe-deficient and Fe-sufficient conditions during the vegetative stage. In leaves, IDEF1 expression was observed in mesophyll cells and in small vascular bundles, whereas IDEF2 was highly expressed in vascular bundles. In root sections, IDEF1 and IDEF2 were highly expressed in secondary roots and inside vascular bundles. IDEF1 was also expressed in pollen from flowers before and after anthesis, in the ovary after fertilization, and in the embryo during seed maturation. IDEF2 was expressed in flowering stage pollen, in immature seeds just after flowering, and in the dorsal vascular region during the late maturation stage. The spatial expression patterns of IDEF1 and IDEF2 partially overlapped with their target genes.

Understanding the habitat requirements of fishes throughout their life cycle is essential for effective conservation. Despite the growing need to conserve anguillid eels, the current understanding of the ontogenetic habitat shifts during their riverine stages remains limited, particularly for the Japanese eel Anguilla japonica and the Indo‐Pacific eel Anguilla marmorata.Here, changes in habitat use during the riverine stages of these two eel species were investigated in the southern Japan rivers, where they coexist. Eels were classified into total length (TL) classes at 10 cm intervals, and generalized additive models were constructed using these classes as an ordinal, quasi‐continuous explanatory variable.The models showed that the habitat use of the two species changed with growth; both species shifted to deeper and more lentic habitats as they grew larger. Small‐ and mid‐sized (<25 and 25–55 cm in TL, respectively) A. japonica used more lentic habitats with smaller substrates, ranging from sand/silt to cobbles, than small‐ and mid‐sized A. marmorata, which mainly used lotic habitats with cobble and boulder substrates. However, compared with small‐sized conspecifics, mid‐sized A. japonica mainly used habitats with larger substrates, such as pebbles and cobbles, suggesting that the interspecific overlap in habitat use is relatively high for mid‐sized individuals of both species. Large A. marmorata (≥85 cm) mainly used habitats with smaller substrates as they grew larger.The results suggest that using a fine body size classification and including these classes as a quasi‐continuous explanatory variable in habitat models capture gradual changes in habitat use, improving habitat use evaluation of anguillid eels. Preserving the environmental heterogeneity of river habitats in terms of water depth, current velocity and substrate size would facilitate habitat segregation of both conspecifics and allospecifics in the same rivers, thereby promoting the conservation of anguillid eels. [ABSTRACT FROM AUTHOR]

Abstract--We propose an extended form of the von Bertalanffy growth function (VBGF), where the allocation of surplus energy to reproduction is considered. Any function can be used in our model [...]

Estimating stock–recruitment (S–R) relationships is a fundamental challenge in fisheries management. However, there is little consensus among fishery scientists on whether a significant quantitative relationship exists between spawning stock biomass (SSB) and recruitment, and whether an optimal model is available to represent this S–R relationship. In this study, we conducted a meta-analysis to determine the relationship between SSB and ln -transformed recruitment per spawning stock (RPS) using data from 92 stocks worldwide by applying four conventional S–R models (the Beverton–Holt, Ricker, Deriso–Schnute, and Pella–Tomlinson models). We also examined the residuals from standard model (SM) and measurement error model (MEM) regressions, which consider only the error in the y -variable and that in both the x - and y -variables, respectively, by integrating them after standardization. We showed that 90.2% of the stocks had significant negative correlations (i.e. density effects) between SSB and ln(RPS). The Pella–Tomlinson S–RPS model exhibited the most stable and high performance in both SM and MEM regressions. Our results suggest the Pella–Tomlinson S–RPS model as the most probable candidate to assess the dynamics of several stocks. [ABSTRACT FROM AUTHOR]