Dingoes are wild canids living in Australia, originating from domestic dogs. They have lived isolated from both the wild and the domestic ancestor, making them a unique model for studying feralization. Here, we sequence the genomes of 10 dingoes and 2 New Guinea Singing Dogs. Phylogenetic and demographic analyses show that dingoes originate from dogs in southern East Asia, which migrated via Island Southeast Asia to reach Australia around 8300 years ago, and subsequently diverged into a genetically distinct population. Selection analysis identifies 50 positively selected genes enriched in digestion and metabolism, indicating a diet change during feralization of dingoes. Thirteen of these genes have shifted allele frequencies compared to dogs but not compared to wolves. Functional assays show that an A-to-G mutation in ARHGEF7 decreases the endogenous expression, suggesting behavioral adaptations related to the transitions in environment. Our results indicate that the feralization of the dingo induced positive selection on genomic regions correlated to neurodevelopment, metabolism and reproduction, in adaptation to a wild environment.

Heterovalent doping of halide perovskite nanocrystals (NCs), offering potential tunability in optical and electrical properties, remains a grand challenge. Here, we report for the first time a controlled doping of monovalent Ag+ into CsPbBr3 NCs via a facile room-temperature synthesis method. Our results suggest that Ag+ ions act as substitutional dopants to replace Pb2+ ions in the perovskite NCs, shifting the Fermi level down toward the valence band and in turn inducing a heavy p-type character. Field effect transistors fabricated with Ag+-doped CsPbBr3 NCs exhibit 3 orders of magnitude enhancement in hole mobility at room temperature, compared with undoped CsPbBr3 NCs. Low-temperature electrical studies further confirm the influence of Ag+ doping on the charge-carrier transport. This work demonstrates the tunability of heterovalent doping on the electrical properties of halide perovskite NCs, shedding light on their future applications in versatile optoelectronic devices.

The Beijing government implemented a number of clean air action plans to improve air quality in the last 10 years, which contributed to changes in the concentration of fine particles and their compositions. However, quantifying the impacts of these interventions is challenging as meteorology masks the real changes in observed concentrations. Here, we applied a machine learning technique to decouple the effect of meteorology and evaluate the changes in the chemistry of nonrefractory PM 1 (particulate matter less than 1 μm) in winter 2007, 2016, and 2017 as a result of the clean air actions. The observed mass concentrations of PM 1 were 74.6, 90.2, and 36.1 μg m −3 in the three winters, while the deweathered concentrations were 74.2, 78.7, and 46.3 μg m −3 , respectively. The deweathered concentrations of PM 1 , organics, sulfate, ammonium, chloride, SO 2 , NO 2 , and CO decreased by −38, −46, −59, −24, −51, −89, −16, and −52% in 2017 in comparison to 2007. On the contrary, the deweathered concentration of nitrates increased by 4%. Our results indicate that the clean air actions implemented in 2017 were highly effective in reducing ambient concentrations of SO 2 , CO, and PM 1 organics, sulfate, ammonium, and chloride, but the control of nitrate and PM 1 organics remains a major challenge.

Platinum dichalcogenide (PtX 2 ), an emergent group-10 transition metal dichalcogenide (TMD) has shown great potential in infrared photonic and optoelectronic applications due to its layer-dependent electronic structure with potentially suitable bandgap. However, a scalable synthesis of PtSe 2 and PtTe 2 atomic layers with controlled thickness still represents a major challenge in this field because of the strong interlayer interactions. Herein, we develop a facile cathodic exfoliation approach for the synthesis of solution-processable high-quality PtSe 2 and PtTe 2 atomic layers for high-performance infrared (IR) photodetection. As-exfoliated PtSe 2 and PtTe 2 bilayer exhibit an excellent photoresponsivity of 72 and 1620 mA W −1 at zero gate voltage under a 1540 nm laser illumination, respectively, approximately several orders of magnitude higher than that of the majority of IR photodetectors based on graphene, TMDs, and black phosphorus. In addition, our PtSe 2 and PtTe 2 bilayer device also shows a decent specific detectivity of beyond 10 9 Jones with remarkable airstability (>several months), outperforming the mechanically exfoliated counterparts under the laser illumination with a similar wavelength. Moreover, a high yield of PtSe 2 and PtTe 2 atomic layers dispersed in solution also allows for a facile fabrication of airstable wafer-scale IR photodetector. This work demonstrates a new route for the synthesis of solution-processable layered materials with the narrow bandgap for the infrared optoelectronic applications.