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In this paper, a new memetic algorithm (MA) for multiobjective (MO) optimization is proposed, which combines the global search ability of particle swarm optimization with a synchronous local search heuristic for directed local fine-tuning. A new particle updating strategy is proposed based upon the concept of fuzzy global-best to deal with the problem of premature convergence and diversity maintenance within the swarm. The proposed features are examined to show their individual and combined effects in MO optimization. The comparative study shows the effectiveness of the proposed MA, which produces solution sets that are highly competitive in terms of convergence, diversity, and distribution.

The new coronavirus, SARS-CoV-2, has spread internationally and whilst the current focus of those dealing with the COVID-19 pandemic is understandably restricting its direct transmission, the potential for secondary transmission via wastewater should not be underestimated. The virus has been identified in human fecal and wastewater samples from different countries and potential cases of transmission via wastewater have been reported. Our recommendations for hospital wastewater treatment, municipal wastewater plants, sewage sludge, water reuse and aquatic environments are designed to reduce the risk of such transmission, and contribute to limiting the resurgence of COVID-19 as current restrictions are relaxed. A particular urgent recommendation focusses on supporting low-income countries in tackling the potential for secondary transmission via wastewater.

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Alternanthera philoxeroides recently expanded its range northwards in China. It is unknown if the range expansion has a genetic and/or epigenetic basis, or merely an environmental basis due to a warming climate. To test these possibilities, we used an RNAseq approach with a common greenhouse design to examine gene expression in individuals from the northern edge and central portion of alligator weed range from China to determine if there were differences in their responses to cold temperatures. We hypothesized that if the recent range expansion was primarily environmental, we would observe few differences or only differences unrelated to low-temperature adaptations. We assembled over 75,000 genes of which over 65,000 had long open reading frames with similarity to sequences from arabidopsis. Differences in expression between northern and southern populations that were both exposed to low temperatures showed similar expression among genes in the C-REPEAT/DRE BINDING FACTOR (CBF) regulon. However, gene set and sub-network enrichment analysis indicated differences in the response of photosynthetic processes and oxidative stress responses were different between the two populations and we relate these differences to cold adaptation. The transcriptome differences in response to cold between the individuals from the two populations is consistent with adaptations potentiating or resulting from selection after expansion into colder environments and may indicate that genetic changes have accompanied the recent northward expansion of A. philoxeroides in China. However, we cannot rule out the possibility of epigenetic changes may have a role in this expansion.

Harness passion of private fossil owners Reproducing palaeontological results depends on unrestricted access to fossils described in the literature, allowing others to reexamine or reinterpret them. Museums have policies and protocols for keeping materials in the public trust, but accessibility to privately owned fossil collections can be a problem. For example, the existence of an important early bat fossil in a private collection was long known, but it was only after a second specimen was acquired and made available by a museum that researchers published a description of it (N. B. Simmons et al. Nature 451, 818-821; 2008). Another example is the unique fossil of a supposed four-legged 'snake' , also privately owned, that was made temporarily available through a private German museum and then withdrawn after its description was published (D. M. Martill et al. Science 349, 416-419; 2015). We suggest that the enthusiasm of private collectors for their valuable and spectacular fossils should instead be harnessed by researchers, to the benefit of both parties. For example, scientists can invite collectors to participate in their projects and be co-authors on the publications

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