Haiyan Hu

The effect of metal–organic framework particle size on capacitive performance in oxygenated saline water was studied, suggesting that as particle size increases, the performance decreases.

As the concept of green development spreads worldwide, environmental protection awareness for production and life has been continuously strengthened. Antibiotic residues in aquaculture wastewaters aggravate environmental pollution and threaten human health. Therefore, the detection of residual antibiotics in wastewater is crucial. In this paper, a new, simple, and low-cost method based on the glassy carbon electrode electrochemical sensor for the detection of sulfadiazine in aquaculture wastewater was developed without using complex materials to modify the electrode surface, to detect sulfadiazine which electrochemically oxidizes directly. The electrochemical performance of the sensor was studied and optimized with differential pulse voltammetry and cyclic voltammetry in the three-electrode system. The optimal electrolyte was acetic acid-sodium acetate buffer, and the optimal pH was 4.0. Finally, based on the optimized conditions, the newly established method showed satisfactory results for detecting sulfadiazine in aquaculture wastewater. The concentration of sulfadiazine and the peak current intensity showed a linear relationship in the range of 20 to 300 μmol/L, and the limit of detection was 6.14 μmol/L, the recovery rate of standard addition was 87–95%, with satisfactory reproducibility and low interference.

The distribution of chlorophyll-a (Chl-a) in the Yangtze River Mouth area was analyzed using a new Chl-a inversion model (PMS-C) based on the relationship between in situ Chl-a and GF-4 PMS band combinations. Combining GF-4 PMS with HY-C CZI, this paper revealed that: (1) Chl-a concentration in Yangtze River Mouth was in the range of 2–6 µg/L, being higher in the west than in the east. The high Chl-a area was mainly distributed near the mouth of the Yangtze River and the Chl-a value was in the range of 3.7 µg/L to 5.9 µg/L. Chl-a concentration is higher in spring and summer than in autumn and winter, with a Chl-a concentration difference of 1–2 µg/L. Chl-a downstream of islands and bridges increased by 0.5–1.7 µg/L compared with upstream. (2) Short-term (within 3 h) changes of Chl-a concentration were effectively detected. In summer and autumn, Chl-a obtained at 13:30 in the noon was generally lower than Chl-a obtained at around 10:30 in the morning and it decreased by nearly 0.1–4 μg/L within three hours on the same day. In winter, the concentration of Chl-a decreased in the range of 0–1.9 μg/L. Generally, within three hours, Chl-a in the downstream of the island decreased significantly from 5 μg/L to about 3.8 μg/L, and Chl-a downstream of piers decreased from 3.7 μg/L to about 3 μg/L. (3) Environmental factors including seawater temperature, illumination, and nutrients, as well as dynamic factors such as wind and tidal current can induce Chl-a change in the Yangtze River Mouth. Short-term change of Chl-a concentration is closely related to the specific hydrodynamic conditions, nutrients, and lighting conditions.

Cathepsin D (Cath D) is overexpressed and secreted in a number of solid tumors and involved in the progress of tumor invasion, proliferation, metastasis, and apoptosis. Inhibition of Cath D is regarded as an attractive pathway for the development of novel anticancer drugs. Our previous studies revealed that tasiamide B, a cyanobacterial peptide that contained a statine-like unit, exhibited good inhibition against Cath D and other aspartic proteases. Using this natural product as prototype, we designed and synthesized three new analogs, which bear isophthalic acid fragment at the N-terminus and isobutyl amine (1), cyclopropyl amine (2), or 3-methoxybenzyl amine (3) moiety at the C-terminus. Enzymatic assays revealed that all these three compounds showed moderate-to-good inhibition against Cath D, with IC₅₀s of 15, 884, and 353 nM, respectively. Notably, compound 1 showed extreme selectivity for Cath D with 576-fold over Cath E and 554-fold over BACE1, which could be a valuable template for the design of highly potent and selective Cath D inhibitors. Additionally, compound 1 showed moderated activity against HeLa cell lines with IC₅₀ of 41.8 μM. Copyright © 2017 European Peptide Society and John Wiley & Sons, Ltd.