Excellent Switchable Properties, Broad-Band Emission, Ferroelectricity, and High Tc in a Two-Dimensional Hybrid Perovskite: (4,4-DCA)2PbBr4 Exploited by H/F Substitution.

Switchable materials have gained significant attention due to their potential applications in data storage, sensors, and switching devices. Two-dimensional (2D) hybrid perovskites have demonstrated promising prospects for designing switchable materials, where the dynamic motion of the organic components coupled with the distortion of the inorganic framework provides the driving force for triggering multifunctional switchable properties. Herein, through the H/F substitution strategy, we report a polar 2D hybrid lead-based perovskite, (4,4-DCA)2PbBr4 (4,4-DCA = 4,4-difluorocyclohexylammonium) (1), which exhibits dual-stable behavior in a dielectric and second harmonic generation (SHG) response during the reversible phase transition process near the high Curie temperature Tc ∼ 409 K. The phase transition temperature is significantly increased by 41 K compared to the corresponding non-fluorinated (CHA)2PbBr4 (CHA = cyclohexylammonium). Remarkably, the material shows rare broad-band yellow emission under UV excitation, attributed to the induction of self-trapped exciton emission by the distortion of the [PbBr6]4- octahedra, as confirmed by the first-principles analysis. 1 also exhibited ferroelectricity with a saturation polarization value and a small coercive field. This study provides a new insight into the modification of multifunctional switchable materials through the H/F substitution strategy.

[Port-owned Mobile Source Air Pollutant Emission Inventory].

Based on the comprehensive development of the emission inventory of air pollution sources, the emission inventory of self-owned mobile sources of Tianjin coastal ports was researched and formulated. In this study, a gridded emission inventory with a resolution of 3 km×3 km was established for six types of air pollutants from road and non-road mobile sources. The spatial and temporal distribution characteristics of pollutant emissions were analyzed, and the uncertainty of the inventory was analyzed using the Monte Carlo method. The results showed that in 2020, the self-owned mobile sources of coastal ports emitted 148.22 t PM10, 135.34 t PM2.5, 1061.04 t SO2, 4027.16 t NOx, 756.60 t CO, and 237.07 t VOCs, of which the total emissions of road and non-road mobile sources accounted for 6.66% and 93.34% of the mobile source emissions, respectively. The main contributors to motor vehicle pollutant emissions from road mobile sources in the whole port area were small, medium, and large passenger vehicles (gasoline) and heavy trucks (diesel). The main contributors to the pollutants emitted by non-road mobile sources were ships and construction machinery. Uncertainty analysis results showed that the overall uncertainty of mobile sources ranged from -13.3% to 16.53%.

Efficacy of Bispecific Antibody Targeting EpCAM and CD3 for Immunotherapy in Ovarian Cancer Ascites: An Experimental Study.

OBJECTIVE: This study aimed to explore the value of M701, targeting epithelial cell adhesion molecule (EpCAM) and CD3, in the immunotherapy of ovarian cancer ascites by the in vitro assay. METHODS: The expression of EpCAM in ovarian cancer tissues was analyzed by databases. The EpCAM expression and immune cell infiltration in different foci of ovarian cancer were detected by 8-channel flow cytometry. The toxic effect of M701 on OVCAR3 was tested using the in vitro cytotoxicity assay. The 3D cell culture and drug intervention experiments were performed to evaluate the therapeutic effect of M701 in ovarian cancer specimens. Flow cytometry was used to examine the effect of M701 on the binding of immune cells to tumor cells and the activation capacity of T cells. RESULTS: The results of the bioinformatic analysis showed that the expression of EpCAM in ovarian cancer tissue was significantly higher than that in normal ovarian tissue. The 8-channel flow cytometry of clinical samples showed that the EpCAM expression and lymphocyte infiltration were significantly heterogeneous among ovarian cancer patients and lesions at different sites. The in vitro experiment results showed that M701 had a significant killing effect on OVCAR3 cells. M701 also obviously killed primary tumor cells derived from some patients with ovarian cancer ascites. M701 could mediate the binding of CD3+ T cells to EpCAM+ tumor cells and induce T cell activation in a dose-dependent manner. CONCLUSION: M701 showed significant inhibitory activity on tumor cells derived from ovarian cancer ascites, which had a promising application in immunotherapy for patients with ovarian cancer ascites.

[Nicorandil improves cognitive dysfunction in mice with streptozotocin-induced diabetes].

OBJECTIVE: To observe the protective effects of potassium channel opener nicorandil against cognitive dysfunction in mice with streptozotocin (STZ)-induced diabetes. METHODS: C57BL/6J mouse models of type 1 diabetes mellitus (T1DM) were established by intraperitoneal injection of STZ and received daily treatment with intragastric administration of nicorandil or saline (model group) for 4 consecutive weeks, with normal C57BL/6J mice serving as control. Fasting blood glucose level was recorded every week and Morris water maze was used to evaluate the cognitive behavior of the mice in the 4th week. At the end of the experiment, the mice were sacrificed to observe the ultrastructural changes in the hippocampus and pancreas under transmission electron microscopy; the contents of glucose-dependent insulinotropic polypeptide (GIP) and glucagon-like peptide-1 (GLP-1) in the hippocampus and SOD activity and MDA level in the brain tissue were determined. RESULTS: Compared with the control group, the model group showed significantly increased fasting blood glucose (P<0.001), significantly prolonged escape latency (P<0.05) and increased swimming distance (P<0.01) with ultrastructural damage of pancreatic ß cells and in the hippocampus; GIP and GLP-1 contents in the hippocampus (P<0.01) and SOD activity in the brain were significantly decreased (P<0.05) and MDA content was significantly increased in the model group (P<0.05). Compared with the model group, nicorandil treatment did not cause significant changes in fasting blood glucose, but significantly reduced the swimming distance (P<0.05); nicorandil did not improve the ultrastructural changes in pancreatic ß cells but obviously improved the ultrastructures of hippocampal neurons and synapses. Nicorandil also significantly increased the contents of GIP and GLP-1 in the hippocampus (P<0.05), enhanced SOD activity (P<0.05) and decreased MDA level (P<0.01) in the brain tissue. CONCLUSION: Nicorandil improves cognitive dysfunction in mice with STZ-induced diabetes by increasing GIP and GLP-1 contents in the hippocampus and promoting antioxidation to relieve hippocampal injury.