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Tropical deforestation can result in substantial changes in local surface energy and water budgets, and thus in atmospheric stability. These effects may in turn yield changes in precipitation. The Maritime Continent (MC) has undergone severe deforestation during the past few decades but it has received less attention than the deforestation in the Amazon and Congo rain forests. In this study, numerical deforestation experiments are conducted with global (i.e., Community Earth System Model) and regional climate models (i.e., Regional Climate Model version 4.6) to investigate precipitation responses to MC deforestation. The results show that the deforestation in the MC region leads to increases in both surface temperature and local precipitation. Atmospheric moisture budget analysis reveals that the enhanced precipitation is associated more with the dynamic component than with the thermodynamic component of the vertical moisture advection term. Further analyses on the vertical profile of moist static energy indicate that the atmospheric instability over the deforested areas is increased as a result of anomalous moistening at approximately 800-850 hPa and anomalous warming extending from the surface to 750 hPa. This instability favors ascending air motions, which enhance low-level moisture convergence. Moreover, the vertical motion increases associated with the MC deforestation are comparable to those generated by La Niña events. These findings offer not only mechanisms to explain the local climatic responses to MC deforestation but also insights into the possible reasons for disagreements among climate models in simulating the precipitation responses.

With the rapid development and application of nuclear energy and technology, a large number of radioactive wastewater was produced, which caused potential pollution to the ecological environment. The research on radioactive wastewater treatment is of great significance to environmental protection. Graphene oxide and its composites have attracted much attention in the field of radioactive wastewater treatment because of their high specific surface area, abundant functional groups, strong adsorption capacity and good chemical stability. Recent research status and progress on adsorption of radionuclides in water by graphene oxide and its composites were reviewed. The adsorption capacity, adsorption isothermal model, adsorption thermodynamics, influencing factors and adsorption mechanism of graphene oxide and its composites for radionuclides were introduced. In the end, the problems and challenges faced by the research on graphene oxide and its composites in the treatment of radionuclides in terms of radiation stability and high adsorption selectivity were analyzed. The key research directions for promoting the application of the graphene oxide and its composites in practical radioactive wastewater treatment projects in the future were discussed, such as the perfect industrial system and actively developing a set of matching water treatment processes and equipments.

We investigated the structural properties of organic–inorganic lead halide perovskite microwires through joint experimental and theoretical Raman spectroscopy. High‐quality methyl ammonium lead iodide (MAPBI3, MA = CH3NH3+) microwires with tetragonal phases and explicit crystalline orientation were prepared. Raman spectroscopy was used in studying the as‐prepared microwires and determining not only the crystal quality but also crystalline orientation of MAPBI3 with the aid of normal mode calculations. High‐quality structural features were verified by well‐resolved Raman peaks related to the inorganic cage (IPbI stretching and bending modes below 100 cm−1), organic MA cation motions (libration ~150–200 cm−1 and torsional ~200–250 cm−1), a coupled mode of cage and MA cation liberation (~105–110 cm−1), and the almost undetectable degraded signal at 95 cm−1. In micro‐Raman mapping, an intensity ratio of 105 and 95 cm−1 was used for the direct imaging of crystal quality along the microwire. The characterization of the crystalline orientation of MAPBI3 microwires posed a challenge, which can be addressed by using polarized Raman technique with normal mode analysis. We believe that the proposed method can be extended to other organic–inorganic lead halide perovskites with different structures, such as polycrystalline films and single crystals. [ABSTRACT FROM AUTHOR]

Perovskite microwires have a larger surface-to-volume ratio and better photoelectric conversion efficiency than perovskite films. The degree of crystallization also affects the optoelectrical performances of perovskite microwires. Laser annealing was regarded as a tool for crystallization. High light absorption induced fast heating process. A 405 nm violet laser located near the absorption peak of typical perovskite films was employed as the annealing laser. In an in situ experimental design, the annealing laser beam was combined into the micro Raman measurement system. Real-time information of the annealing and crystallization was provided. Many excellent works were done, and typically needed offline optoelectronic measurements. An mW-level continuous-wave laser beam can provide enough kinetic energy for crystalline in perovskite microwires. The thermal distribution of the perovskite microwire under the annealing laser beams was considered here. Polarized Raman signals can provide evidence of the perovskite microwires crystallization. This work offered the novel approach of an on-site, real-time laser-induced thermal annealing design for perovskite microwires. This approach can be used in other material procedures. Intensity-dependent conditions were crucial for the annealing processes and analyzed in detail. The substrate effect was found. This proposed scheme provided integrated novel, scalable, and highly effective designs of perovskite-based devices. [ABSTRACT FROM AUTHOR]

mcr-1, the first plasmid-mediated colistin-resistance gene, can mediate polymyxin resistance and be transferred horizontally via plasmids. Many studies have confirmed its distribution via epidemic plasmids (IncI2, IncX4, IncHI2, etc.), as well as mobile genetic elements, among Enterobacteriaceae isolated from animals, humans, and the environment in 35 countries. These studies provide the basis of understanding the complicated mechanism of colistin resistance mediated by MCR-1 and its global dissemination and epidemic properties, and also enrich antimicrobial resistance mechanisms. Here, we review the latest advances in the prevalence, resistance mechanism, transfer mechanism, and genetic environments of mcr-1 in isolates recovered from various samples worldwide. Finally, we discuss the clinical risk and the corresponding solutions, aiming to provide a basis for researchers and clinical scientists to face the serious challenge of antimicrobial resistance together.