27 research outputs found
Blue and Green Phosphorescent Liquid-Crystalline Iridium Complexes with High Hole Mobility
Blue- and green-emitting cyclometalated liquid-crystalline iridium complexes are realized by using a modular strategy based on strongly mesogenic groups attached to an acetylacetonate ancillary ligand. The cyclometalated ligand dictates the photophysical properties of the materials, which are identical to those of the parent complexes. High hole mobilities, up to 0.004 cm2 V-1 s-1, were achieved after thermal annealing, while amorphous materials show hole mobilities of only approximately 10-7-10-6 cm2 V-1 s-1, similar to simple iridium complexes. The design strategy allows the facile preparation of phosphorescent liquid-crystalline complexes with fine-tuned photophysical properties
Analysis of resistance and virulence genes of foodborne Staphylococcus aureus in northwestern Hubei Province
Objective To understand the prevalence, drug resistance, and virulence gene distribution of foodborne Staphylococcus aureus in northwestern Hubei Province. Methods A total of 303 food samples were collected from Xiangyang City, Shiyan City, and Suizhou City of Hubei Province for Staphylococcus aureus screening. Toxic genes and methicillin-resistant Staphylococcus aureus (MRSA) were detected with PCR method. The drug resistance of Staphylococcus aureus was determined with K-B paper diffusion method. Results Staphylococcus aureus strain was determined from 41 samples with the positive rate of 13.53%. Among them, the highest detection rate was from raw meat products (23.91%, 22/92). Among the enterotoxigenic strains, the strain carrying sea was the most common, accounting for 87.80% (36/41). The strains carrying eta and tst accounted for 97.56% (40/41) and 7.32% (3/41), respectively. Strains carrying three or more enterotoxin genes accounted for 17.07% (7/41). 2.44% (1/41) of strains carry eta and tst simultaneously. The drug susceptibility result showed that the penicillin, tetracycline, erythromycin, and doxycycline accounted for 78.05% (32/41), 43.90% (18/41), 31.71% (13/41) and 21.95% (9/41) respectively. The mecA gene test showed that 19.51% (8/41) of the strains were MRSA strains. Conclusion Foodborne Staphylococcus aureus in northwestern Hubei Province had a higher detection rate, toxic gene carring rate, and multiple drug resistance. Related departments need to strengthen food safety monitoring to control the spread of the strain
Adjusting aggregation modes and photophysical and photovoltaic properties of diketopyrrolopyrrole-based small molecules by introducing B←N bonds
The packing mode of small-molecular semiconductors in thin films is an important factor that controls the performance of their optoelectronic devices. Designing and changing the packing mode by molecular engineering is challenging. Three structurally related diketopyrrolopyrrole (DPP)-based compounds were synthesized to study the effect of replacing C−C bonds by isoelectronic dipolar B←N bonds. By replacing one of the bridging C−C bonds on the peripheral fluorene units of the DPP molecules by a coordinative B←N bond and changing the B←N bond orientation, the optical absorption, fluorescence, and excited-state lifetime of the compounds can be tuned. The substitution alters the preferential aggregation of the molecules in the solid state from H-type (for C−C) to J-type (for B←N). Introducing B←N bonds thus provides a subtle way of controlling the packing mode. The photovoltaic properties of the compounds were evaluated in bulk heterojunctions with a fullerene acceptor and showed moderate performance as a consequence of suboptimal morphologies, bimolecular recombination, and triplet-state formation
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TNFAIP1 contributes to the neurotoxicity induced by Aβ25–35 in Neuro2a cells
Background: Amyloid-beta (Aβ) accumulation is a hallmark of Alzheimer’s disease (AD) that can lead to neuronal dysfunction and apoptosis. Tumor necrosis factor, alpha-induced protein 1 (TNFAIP1) is an apoptotic protein that was robustly induced in the transgenic C. elegans AD brains. However, the roles of TNFAIP1 in AD have not been investigated. Results: We found TNFAIP1 protein and mRNA levels were dramatically elevated in primary mouse cortical neurons and Neuro2a (N2a) cells exposed to Aβ25–35. Knockdown and overexpression of TNFAIP1 significantly attenuated and exacerbated Aβ25–35-induced neurotoxicity in N2a cells, respectively. Further studies showed that TNFAIP1 knockdown significantly blocked Aβ25–35-induced cleaved caspase 3, whereas TNFAIP1 overexpression enhanced Aβ25–35-induced cleaved caspase 3, suggesting that TNFAIP1 plays an important role in Aβ25–35-induced neuronal apoptosis. Moreover, we observed that TNFAIP1 was capable of inhibiting the levels of phosphorylated Akt and CREB, and also anti-apoptotic protein Bcl-2. TNFAIP1 overexpression enhanced the inhibitory effect of Aβ25–35 on the levels of p-CREB and Bcl-2, while TNFAIP1 knockdown reversed Aβ25–35-induced attenuation in the levels of p-CREB and Bcl-2. Conclusion: These results suggested that TNFAIP1 contributes to Aβ25–35-induced neurotoxicity by attenuating Akt/CREB signaling pathway, and Bcl-2 expression
Synthesis and photovoltaic performance of DPP-based small molecules with tunable energy levels by altering the molecular terminals
Synthesis and photovoltaic properties of new small molecules with rhodanine derivative as the end-capped blocks
Manipulating backbone structure with various conjugated spacers to enhance photovoltaic performance of D–A-type two-dimensional copolymers
Truxene-Centered Electron Acceptors for Non-Fullerene Solar Cells: Alkyl Chain and Branched Arm Engineering
A series of symmetrical truxene-centered and 3-ethylrhodanine end-capped electron acceptors with high absorption coefficient, namely Tr(Hex)6-3RD, Tr(Dec)6-3RD, and Tr(Hex)6-6RD, were prepared and constructed for non-fullerene solar cells. To satisfy solution-processability, multiple energy levels, and suitable morphology, these three acceptors were comparatively studied through alkyl chain (hexyl/decyl) and branched-arm engineering (three/six branched arms). The six-bladed propeller acceptor of Tr(Hex)6-6RD recorded the power conversion efficiency (PCE) of 1.1% blending with PTB7-Th without additional additives and post-processing. This work highly broadens the potential applications of star-shaped truxene building blocks in the fields of organic electronics