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Self-assembled wormlike micelles (WLMs) are widely studied in small-molecule surfactants due to their unique ability to break and recombine; however, less is known about the structure and dynamics of nonionic polymer WLMs. Here, solutions of seven triblock poloxamers, composed of poly(propylene oxide) (PPO) midblocks and poly(ethylene oxide) (PEO) end blocks, are comprehensively examined to determine the role of poloxamer composition, temperature, and inorganic salt type and concentration on rod formation and subsequent elongation into WLMs. Phase separation and sphere-to-rod transition temperatures were quantified via cloud point measurements and shear rheology, respectively, and corroborated with small-angle neutron scattering (SANS). The local microstructure of resulting rodlike micelles is remarkably similar across poloxamer type and sodium fluoride (NaF) or sodium chloride (NaCl) content. Salt addition reduces transition temperatures, with the most pronounced effects for poloxamers with high PEO molecular weights and PEO fractions. Between these two temperatures, several poloxamers elongate into WLMs, where shear rheology detects increases in viscosity up to 6 orders of magnitude. Despite similar local microstructures, poloxamer identity and salt content impact micelle growth substantially, where large poloxamers with lower PEO fractions exhibit the highest viscosities and longest relaxation times. While sodium fluoride has little impact on micelle growth, increasing NaCl concentration dramatically increases the WLM viscosity and relaxation time. This result is explained by different interactions of each salt with the micelle: whereas NaF interacts primarily with PEO chains, NaCl may also partition to the PPO/PEO interface in low levels, increasing micelle surface tension, scission energy, and contour length.

Various studies have found that reading books about positive interactions between ingroup and outgroup characters, known as media vicarious contact, can reduce prejudice. Focusing on the fantasy saga of The Hunger Games, we examined the effects of negative vicarious contact on collective action across two studies. Specifically, we tested whether reading about fantasy characters living in a postapocalyptic conflictual society with large social disparities between advantaged and disadvantaged groups leads advantaged group members to display greater willingness to engage in collective action on behalf of the disadvantaged group. Results from Study 1 (correlational survey in the United Kingdom and United States) and Study 2 (experimental intervention in Italy) revealed that reading The Hunger Games is indirectly associated with greater collective action intentions via increased anger toward injustice. In both studies social dominance orientation (SDO) acted as a moderator, but in opposite directions: mediation was significant for low-SDOs in Study 1, and for high-SDOs in Study 2. Results are discussed in relation to the importance of media vicarious contact via book reading for social change, and to the need to identify the contextual conditions allowing to anticipate the specific moderation pattern that is more likely to emerge.

Genomic maps of DNA G-quadruplexes (G4s) can help elucidate the roles that these secondary structures play in various organisms. Herein, we employ an improved version of a G-quadruplex sequencing method (G4-seq) to generate whole genome G4 maps for 12 species that include widely studied model organisms and also pathogens of clinical relevance. We identify G4 structures that form under physiological K+ conditions and also G4s that are stabilized by the G4-targeting small molecule pyridostatin (PDS). We discuss the various structural features of the experimentally observed G-quadruplexes (OQs), highlighting differences in their prevalence and enrichment across species. Our study describes diversity in sequence composition and genomic location for the OQs in the different species and reveals that the enrichment of OQs in gene promoters is particular to mammals such as mouse and human, among the species studied. The multi-species maps have been made publicly available as a resource to the research community. The maps can serve as blueprints for biological experiments in those model organisms, where G4 structures may play a role.

The Lund-Spathelf House is located at 1526 Pontiac Trail in Ann Arbor, Michigan. During a recent renovation, the owner sought information regarding the construction of the house by searching through numerous written records. Despite an extensive history of the land on which the house currently sits, neither a construction year nor general period of construction could be obtained. Therefore, four samples of oak (Quercus spp.) were extracted from floor boards throughout the house for dendrochronological dating. The four samples crossdated conclusively with each other both visually and statistically and were used to build a floating 126-year tree-ring chronology. We used COFECHA to statistically evaluate the absolute temporal placement of this chronology against a nearby regional chronology (MI005.CRN) from the Cranbrook Institute, Michigan. The Lund-Spathelf House chronology was anchored in time with the regional chronology from A.D. 1720 to 1845 with a correlation coefficient of 0.62 (p < 0.0001, ...

DNA sequence information underpins genetic research, enabling discoveries of important biological or medical benefit. Sequencing projects have traditionally used long (400-800 base pair) reads, but the existence of reference sequences for the human and many other genomes makes it possible to develop new, fast approaches to re-sequencing, whereby shorter reads are compared to a reference to identify intraspecies genetic variation. Here we report an approach that generates several billion bases of accurate nucleotide sequence per experiment at low cost. Single molecules of DNA are attached to a flat surface, amplified in situ and used as templates for synthetic sequencing with fluorescent reversible terminator deoxyribonucleotides. Images of the surface are analysed to generate high-quality sequence. We demonstrate application of this approach to human genome sequencing on flow-sorted X chromosomes and then scale the approach to determine the genome sequence of a male Yoruba from Ibadan, Nigeria. We build an accurate consensus sequence from >30x average depth of paired 35-base reads. We characterize four million single-nucleotide polymorphisms and four hundred thousand structural variants, many of which were previously unknown. Our approach is effective for accurate, rapid and economical whole-genome re-sequencing and many other biomedical applications.