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Choosing the appropriate population size for differential evolution (DE) is still a challenging task. Too large population size leads to slow convergence, while too small population size causes premature convergence and stagnation. To solve this problem, a population reduction with individual similarity (PRS) for DE is proposed in this paper. In the PRS, a linear differential decrease method is used to automatically determine the population size required in each generation. At the same time, the current population is divided into two subgroups with equal sizes according to individual similarity, and the individuals that need to be removed are determined from the subgroup with the lowest individual similarity in an effective manner, and thus the convergence is further accelerated without affecting the population diversity. In addition, an elite-oriented strategy is utilized to replace the random selection of individuals in the original mutation strategy of DE, which provides constructive guidance for individual evolution and improves the convergence quality. Five basic DE and six advanced DE algorithms are used to evaluate the effect of PRS, and it is further compared with four improved DE algorithms with population reduction strategy. The experimental results on CEC 2014 benchmark functions show that the proposed PRS can effectively enhance the performance of these five basic DE and six advanced DE algorithms, and is better than the four population reduction strategies. [ABSTRACT FROM AUTHOR]

Third-party punishment (TPP) has been shown to be an effective mechanism for maintaining human cooperation. However, it is puzzling how third-party punishment can be maintained, as punishers take on personal costs to punish defectors. Although there is evidence that punishers are preferred as partners because third-party punishment is regarded by bystanders as a costly signal of trustworthiness, other studies show that this signaling value of punishment can be severely attenuated because third-party helping is viewed as a stronger signal of trustworthiness than third-party punishment. Third-party helpers donate their payoffs to victims of defection in games instead of punishing defectors as third-party punishers do. Then, under what circumstances can third-party punishment be maintained by costly signaling when helping is also present? We show that punishers are preferred over helpers by fourth-party individuals as their delegates to deter potential exploitation. This suggests that costly signaling can facilitate the maintenance of third-party punishment in partner choice with delegation interactions. [ABSTRACT FROM AUTHOR]

High-performance mixed-matrix membranes (MMMs) featuring with superior permselectivity and easy processability are highly demanded toward the effective pervaporation recovery of bio-alcohols, however their development still remains a huge challenge. In this work, a self-standing and exceptional zeolitic imidazolate framework (ZIF-8)@Aramid nanofiber/Polydimethylsiloxane (Z@A/P) MMM was constructed via an ingenious "three-dimensional (3D) connecting MOFs pre-forming & polymer backfilling" coupling strategy. The preformed hybrid aerogel network (ZIF-8@Aramid nanofiber) not only exhibited a desirable interfacial compatibility with PDMS but also facilitated ZIF-8 particles to form interconnected 3D long-range consecutive MOF phases across the MMM. Moreover, benefiting from the combination of highly permeable and selective molecular inner channels of ZIF-8 nanoparticles along with their formed continuous and fast transport pathways deriving from the long-range connected assembly phases, the pervaporation performance of the resulting MMMs was greatly enhanced compared to that of physical blending-obtained MMM counterpart. Particularly, an excellent total flux of 935 g m−2 h−1 along with a high separation factor of 19.6 was achieved for the optimized Z@A/P4 MMM even with a relatively low loading of 4.9 wt% for pervaporation recovery of n -butanol from its 1.5 wt% aqueous solution. Therefore, this novel fabrication strategy opens up a new avenue to achieve the high-performance MMMs with the 3D interconnected long-range consecutive MOF phases across the membrane toward the efficient bio-alcohols recovery and other related fields. [Display omitted] • "3D connecting MOFs pre-forming & polymer backfilling" preparation strategy is first proposed. • 3D aramid nanofibers (ANFs) gel skeleton induces the successive growth and deposition of ZIF-8. • The interconnected 3D long-range continuous distribution of MOF phases across the membrane is achieved. • The mixed membrane possesses abundant continuous and fast permselective transport pathways for butanol molecules. • Underlying mechanism for simultaneously improved permeability and selectivity of membranes is explored. [ABSTRACT FROM AUTHOR]

• Standardized anomaly of ecosystem varies with vegetation indices. • Croplands have higher resilience and lower resistance than that of forest. • Ecosystem under drought tended to have greater suppressive effect on GPP. The increasing frequency and intensity of climate extremes have profound impacts on ecosystem function, structure, and stability. Drought is one of the most complex hydrological and climate disasters, and its intensity and duration cause varying degrees of damage to terrestrial ecosystems. Resistance and resilience are crucial concepts for recognizing and understanding the effects of ecosystems on drought events. However, little research has been carried out in southwest China, which experienced severe drought between 2000 and 2018. In this study, the 3-month standardized anomaly (SA) of the Stand Precipitation-Evapotranspiration Index (SPEI) was used to assess ecosystem drought parameters, including onset, duration, severity, and recovery time in 8 plant functional types (PFTs) across the ecosystems in southwest China. By combining vegetation greenness and productivity data, including vegetation greenness indices of Enhanced Vegetation Index (EVI), Normalized Difference Vegetation Index (NDVI), Leaf Area Index (LAI), and productivity index of Gross Primary Production (GPP), the resistance and resilience of the ecosystem were quantified. Our results showed that, spatially, northwestern and southeastern Sichuan and southeastern Yunnan experienced severe drought. Compared to vegetation productivity of GPP (SA value is 0.03), the vegetation greenness indices of EVI (SA value is 0.07), NDVI (SA value is 0.07), and LAI (SA value is 0.20) exhibited lower vulnerability to droughts. Furthermore, the effects of drought on ecosystem resistance and resilience varied with vegetation indices and PFTs, and resistance (mean value is 0.72) was greater than resilience (mean value is 0.56). Across different PFTs, there was a trade-off between resistance and resilience: higher resistance tended to have lower resilience in forests and woody savannas. These findings propose ways to enrich our understanding of ecosystem resistance and resilience to droughts, and recommend the importance of using validated sensitivity indicators to quantify the ecosystem's resistance and resilience to droughts. [ABSTRACT FROM AUTHOR]