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Many studies have recently been done on understanding the sources and formation mechanisms of atmospheric aerosols at ground level. However, vertical profiles and sources of size-resolved particulate matter within the urban boundary layer are still lacking. In this study, vertical distribution characteristics of size-segregated particles were investigated at three observation platforms (ground level, 118 m, and 488 m) on the 610 m high Canton Tower in Guangzhou, China. Size-segregated aerosol samples were simultaneously collected at the three levels in autumn and winter. Major aerosol components, including water-soluble ions, organic carbon, and elemental carbon, were measured. The results showed that daily average fine-particle concentrations generally decreased with height. Concentrations of sulfate and ammonium in fine particles displayed shallow vertical gradients, and nitrate concentrations increased with height in autumn, while the chemical components showed greater variations in winter than in autumn. The size distributions of sulfate and ammonium in both seasons were characterized by a dominant unimodal mode with peaks in the size range of 0.44–1.0 µm. In autumn, the nitrate size distribution was bimodal, peaking at 0.44–1.0 and 2.5–10 µm, while in winter it was unimodal, implying that the formation mechanisms for nitrate particles were different in the two seasons. Our results suggest that the majority of the sulfate and nitrate is formed from aqueous-phase reactions, and we attribute coarse-mode nitrate formation at the measurement site to the heterogeneous reactions of gaseous nitric acid on existing sea-derived coarse particles in autumn. Case studies further showed that atmospheric aqueous-phase and heterogeneous reactions could be important mechanisms for sulfate and nitrate formation, which, in combination with adverse weather conditions such as temperature inversion and calm wind, led to haze formation during autumn and winter in the Pearl River Delta (PRD) region.

The mechanism by which tumor-associated macrophages (TAMs) affect cancer progression is not fully understood. This study developed a microfluidic-based co-culture device to mimic the tumor microenvironment to assess TAM effects on invasion and metastasis in NSCLC. The results showed lung carcinoma cells could cause macrophages to show the M2 (a TAM-like) phenotype, and these M2 macrophages promoted lung cancer cell EMT and invasion. Proteomic analysis by the iTRAQ quantitation strategy and GO ontology of the cancer cells indicated that αB-Crystallin (CRYAB) might be involved in this process. Further, we confirmed the role of CRYAB in cancer invasion and metastasis through cell and animal experiments, as well as human cancer tissue assessment. Overall, we demonstrated that M2 macrophages promote malignancy in lung cancer through the EMT by upregulating CRYAB expression and activating the ERK1/2/Fra-1/slug signaling pathway.

Absorption is one of the most important methods for oil spill cleanup. An ideal absorbent is expected to possess advantages of low cost, green, high absorption capacity and excellent reusability. In this paper, a facile and environmentally-friendly top-down approach was developed for the preparation of the highly mesoporous and compressible sugarcane aerogel. Individualization of cellulose microfibrils within the sugarcane cell wall structure without introducing mechanical disintegration was realized, prepared by oxidation of delignified sugarcane at the neutral condition with TEMPO/NaClO/NaClO2 system. The results proved that the cellulose nanofibers in the cell wall maintains their natural alignment structure. The high fibril orientation and ordered arrangement of the network-like microstructure can be processed into anisotropic aerogels with high porosity (98.8%) and high compressive strength (0.53 MPa at 80% strain). The increased porosity and partial cellulose fibrillation result in specific surface areas of 32.94 m2/g. Subsequent hydrophobic coating with methyltrimethoxysilane, the hydrophobic and oleophilic sugarcane aerogel (water contact angle as high as 145.73°) was capable of adsorbing a wide range of organic solvents and oils (22.8 ~ 40.2 g/g). Moreover, the porous aerogel maintained a high oil-absorption capacity after absorbing and squeezing multiple times. This new sugarcane aerogel offers potential possibilities for the subsequent in high efficiency oil–water separation applications.

Diaporthe helianthi is one of the main fungal pathogens responsible for causing phomopsis stem canker and significant yield losses of sunflowers. In this study, the calmodulin ( Cal ) gene of D. helianthi was selected to develop a rapid detection method involving recombinase polymerase amplification (RPA) combined with CRISPR/Cas12a-based detection at 37 °C. The developed detection system could complete the specific detection of D. helianthi in 45 min, including 25 min for RPA and 20 min for CRISPR/Cas12 reaction. The detection system could be coupled with both lateral flow test strips and fluorescence signal reading modes. The detection limit for lateral flow assay was 1 pg/μL genomic D. helianthi DNA (14 copies/µL); The detection limit for fluorescence signal was 0.1 pg/μL genomic DNA (1.4 copies/µL), approximately 100 times higher than that of the real-time PCR. Thus, the developed RPA/CRISPR-Cas12a system meets the need for portable detection of D. helianthi on-site at ports and in the field.

In this work, CuInGa alloy precursor films are fabricated by co-sputtering of CuIn and CuGa targets simultaneously. After selenization in a tube-type rapid thermal annealing system under a Se atmosphere, the Cu(In, Ga)Se 2 (CIGS) absorber layers are obtained. Standard soda lime glass (SLG)/Mo/CIGS/CdS/i-ZnO/ITO/Ag grid structural solar cells are fabricated based on the selenized CIGS absorbers. The influences of selenization temperatures on the composition, crystallinity, and device performances are systematically investigated by x-ray energy dispersive spectroscopy, x-ray diffraction, Raman spectroscopy, and the current density–voltage ( J – V ) measurement. It is found that the elemental ratio of Cu/(In + Ga) strongly depends on the selenization temperatures. Because of the appropriate elemental ratio, a 9.92% conversion efficiency is reached for the CIGS absorber selenized at 560°C. After the additional optimization by pre-annealing treatment at 280°C before the selenization, a highest conversion efficiency of 11.19% with a open-circuit ( V oc ) of 456 mV, a short-circuit ( J sc ) of 40.357 mA/cm 2 and a fill factor of 60.82% without antireflection coating has been achieved. Above 13% efficiency improvement was achievable. Our experimental findings presented in this work demonstrate that the post-selenization of co-sputtered CuIn and CuGa precursor is a promising way to fabricate high quality CIGS absorbers.

In this work, CuInGa alloy precursor films are fabricated by co-sputtering of CuIn and CuGa targets simultaneously. After selenization in a tube-type rapid thermal annealing system under a Se atmosphere, the Cu(In, Ga)Se2 (CIGS) absorber layers are obtained. Standard soda lime glass (SLG)/Mo/CIGS/CdS/i-ZnO/ITO/Ag grid structural solar cells are fabricated based on the selenized CIGS absorbers. The influences of selenization temperatures on the composition, crystallinity, and device performances are systematically investigated by x-ray energy dispersive spectroscopy, x-ray diffraction, Raman spectroscopy, and the current density-voltage (J-V) measurement. It is found that the elemental ratio of Cu/(In + Ga) strongly depends on the selenization temperatures. Because of the appropriate elemental ratio, a 9.92% conversion efficiency is reached for the CIGS absorber selenized at 560°C. After the additional optimization by pre-annealing treatment at 280°C before the selenization, a highest conversion efficiency of 11.19% with a open-circuit (V oc) of 456 mV, a short-circuit (J sc) of 40.357 mA/cm2 and a fill factor of 60.82% without antireflection coating has been achieved. Above 13% efficiency improvement was achievable. Our experimental findings presented in this work demonstrate that the post-selenization of co-sputtered CuIn and CuGa precursor is a promising way to fabricate high quality CIGS absorbers.