No abstract

In this study, eleven commonly used antibiotics including sulfonamides, tetracyclines, aminoglycosides, fluoroquinolones, and beta-lactams were evaluated for their acute and chronic aquatic toxicities using standard test organisms e.g., Vibrio fischeri, Daphnia magna, Moina macrocopa, and Oryzias latipes. Among the antibiotics tested for acute toxicity, neomycin was most toxic followed by trimethoprim, sulfamethoxazole and enrofloxacin. Sulfamethazine, oxytetracycline, chlortetracycline, sulfadimethoxine and sulfathiazole were of intermediate toxicity, while ampicillin and amoxicillin were least toxic to the test organisms. There were no trends in sensitivity among test organisms or among different classes of the antibiotics. Only the beta-lactam class was the least toxic. In chronic toxicity test, neomycin affected reproduction and adult survival of D. magna and M. macrocopa with low mg/l levels exposure. Predicted no effect concentrations (PNECs) were derived from the acute and chronic toxicity information gleaned from this study and from literature. When the PNECs were compared with measured environmental concentrations (MECs) reported elsewhere for the test compounds, hazard quotients for sulfamethoxazole, sulfathiazole, chlortetracycline, oxytetracycline, and amoxicillin exceeded unity, which suggests potential ecological implication. Therefore, further studies including monitoring and detailed toxicological studies are required to assess potential ecological risk of these frequently used veterinary antibiotics.

Highly efficient inverted BHJ solar cells were demonstrated using a wet-chemically prepared doped ZnO layer with a self-organized ripple nanostructure. The solar cell based on PTB7 and PC71BM with Li2CO3-doped ZnO layer yielded a maximum efficiency of 10.08%.

Long non-coding RNAs (lncRNAs) have been reported to play important roles in cellular metabolism and development. Various diseases have been associated with aberrant expression of lncRNAs and the related dysregulation of mRNAs. An lncRNA profiling assay was carried out to identify the key lncRNA in osteoarthritic human synoviocytes; the results revealed that prostate cancer gene expression marker 1 (PCGEM1) was significantly overexpressed in osteoarthritic synoviocytes. Exogenous overexpression of PCGEM1 inhibited apoptosis, induced autophagy, and stimulated the proliferation of human synoviocytes. The increased expression of PCGEM1 in human synoviocytes also suppressed the expression of miR-770. Transfection of the miR-770 precursor resulted in reduced proliferation, and induced apoptosis of human synoviocytes. This effect of miR-770 expression was reversed by co-introduction of PCGEM1. Target validation showed a direct binding between PCGEM1 and miR-770. We demonstrate that PCGEM1 act as sponge lncRNA for miR-770 that regulates proliferation/apoptosis and autophagy, and suggest PCGEM1 as possible target for OA therapy.

A charge transport layer based on transition metal‐oxides prepared by an anhydrous sol–gel method normally requires high‐temperature annealing to achieve the desired quality. Although annealing is not a difficult process in the laboratory, it is definitely not a simple process in mass production, such as roll‐to‐roll, because of the inevitable long cooling step that follows. Therefore, the development of an annealing‐free solution‐processable metal‐oxide is essential for the large‐scale commercialization. In this work, a room‐temperature processable annealing‐free “aqueous” MoO x solution is developed and applied in non‐fullerene PBDB‐T‐2F:Y6 solar cells. By adjusting the concentration of water in the sol–gel route, an annealing‐free MoO x with excellent electrical properties is successfully developed. The PBDB‐T‐2F:Y6 solar cell with the general MoO x prepared by the anhydrous sol–gel method shows a low efficiency of 7.7% without annealing. If this anhydrous MoO x is annealed at 200 °C, the efficiency is recovered to 17.1%, which is a normal value typically observed in conventional structure PBDB‐T‐2F:Y6 solar cells. However, without any annealing process, the solar cell with aqueous MoO x exhibits comparable performance of 17.0%. In addition, the solar cell with annealing‐free aqueous MoO x exhibits better performance and stability without high‐temperature annealing compared to the solar cells with PEDOT:PSS.

Engineered nanoparticles (ENPs) will be released to the environment during use or following the disposal of ENP-containing products and concerns have been raised over the risks of ENPs to the environment. Many studies have explored the toxicity of ENPs to aquatic organisms but these studies have usually been performed with little understanding of the ENPs' behaviour in the test media and the relationship between behaviour in the media to behaviour in natural waters. This study evaluated and compared the aggregation behaviour of four model gold nanoparticle (NP) types (coated with neutral, negative, positive and amphoteric cappings) in standard ecotoxicity test media and natural waters. The effects of humic acid (HA) and test organisms on aggregation were also investigated. In standard media, positive and neutral NPs were stable, whereas amphoteric and negative NPs generally showed substantial aggregation. In natural waters, amphoteric NPs were generally found to be stable, neutral and positive NPs showed substantial aggregation while negative NPs were stable in some waters and unstable in others. HA addition stabilised the amphoteric NPs, destabilised the positive NPs and had no effect on stability of negative NPs. The presence of invertebrates generally lowered the degree of particle aggregation while macrophytes had no effect. Given the dramatically different behaviours of ENPs in various standard media and natural waters, current regulatory testing may either under- or overestimate the toxicity of nanomaterials to aquatic organisms. Therefore, there is a pressing need to employ ecotoxicity media which better represent the behaviour of ENPs in natural system.

Inexpensive (<$300) real-time particulate matter monitors (IRMs), using laser as a light source, have been introduced for use with a Wi-Fi function enabling networking with a smartphone. However, the information of measurement error of these inexpensive but convenient IRMs are still limited. Using ESCORTAIR (ESCORT, Seoul, Korea) and PurpleAir (PA) (PurpleAir U.S.A.), we evaluated the performance of these two devices compared with the U.S. Environmental Protection Agency (EPA) Federal Equivalent Monitoring (FEM) devices, that is, GRIMM180 (GRIMM Aerosol, Germany) for the indoor measurement of pork panfrying or secondhand tobacco smoking (SHS) and Beta-ray attenuation monitor (BAM) (MetOne, Grants Pass, OR) for outdoor measurement at the national particulate matter (PM2.5) monitoring site near an urban traffic hotspot in Daejeon, South Korea, respectively. The PM2.5 concentrations measured by ESCORTAIR and PA were strongly correlated to FEM (r = 0.97 and 0.97 from indoor pan frying; 0.92 and 0.86 from indoor SHS; 0.85 and 0.88 from outdoor urban traffic hotspot). The two IRMs showed that PM2.5 mass concentrations were increased with increased outdoor relative humidity (RH) levels. However, after applying correction factors for RH, the Median (Interquartile range) of difference compared to FEM was (14.5 (6.1~23.5) %) for PA and 16.3 (8.5–28.0) % for ESCORTAIR, supporting their usage in the home or near urban hotspots.

Inverted type perovskite solar cells (PSCs) have recently emerged as a major focus in academic and industrial photovoltaic research. Their multiple advantages over conventional PSCs include easy processing, hysteresis‐free behavior, high stability, and compatibility for tandem applications. However, the maximum power conversion efficiency (PCE) of inverted PSCs still lags behind those of conventional PSCs because suitable charge‐selective materials for inverted PSCs are limited. In this study, excellent hole‐selective materials for inverted PSCs are introduced. A series of tricyclic aromatic rings containing O, S, or Se, respectively, as a core heteroatom, along with a phosphonic acid anchor, form a self‐assembled monolayer (SAM) that directly contacts the perovskite absorber. The influence of heteroatoms in the aromatic structure on the molecular energetics and operating characteristics of the corresponding inverted PSCs is investigated using complementary experimental techniques as well as density functional theory (DFT) calculations. It is found that all of the SAMs formed an energetically well‐aligned interface with the perovskite absorber. The interaction energy between the Se‐containing SAM and perovskite absorber is the strongest among the series and it reduces the interfacial defect density, in turn leading to an extended charge carrier lifetime. As a result, PSCs incorporating the Se‐containing SAM achieves a PCE of 22.73% and retains ≈96% of their initial efficiency after a maximum power point tracking test of 500 h without encapsulation under ambient conditions. All of the SAMs are then employed in organic solar cells (OSCs). Again, the Se‐containing SAM‐based OSCs demonstrates the highest PCE of 17.9% among the three molecular SAM‐based OSCs. This study demonstrates the great potential for precisely engineered SAMs for use in high‐performance solar cells.