ABSTRACT
The all-fused-ring acceptor (AFRA) is a success for nonfullerene materials and has attracted considerable attention as its high optical and chemical stability expected to reduce energy loss, and power conversion efficiency (PCE) approaching 15% in constructed all-small-molecule organic solar cells (OSCs). Herein, the intrinsic role of the structure of AFRA F13 and the reason for its high PCE were revealed by comparison with those of typical fused acceptors IDT-IC and Y6. An increased degree of conjugation in F13 leads to broader and red-shifted absorption peaks, facilitating enhancement of the short-circuit current. Multiple charge-transfer mechanisms are mainly attributed to the higher Frenkel exciton (FE) state due to the multiple transition ways for acceptors in the C1-CN:F13 system. The increased number of atoms contributing to the charge-transfer (CT) state facilitated the existence of more superior stacking patterns with easy formation of CT and FE/CT states and a high charge separation rate. It was found using the AFRA is an effective strategy to enhance end-group stacking, enhancing the borrowing of oscillator strength to promote multiple CT mechanisms in the complexes, explaining the high performance of this OSC device. This work is promising to guide designing an efficient AFRA in the future.
ABSTRACT
Background and Purpose: The main goal of hospice care is to improve the quality of life for people who are at the end-of-life phase. However, investigations on the awareness of hospice care among community-dwelling elderly participants are limited. This work aimed to reveal the awareness status of hospice care and explore the factors influencing the awareness rate among elderly participants. Methods: A questionnaire survey was conducted among individuals aged 60 years and above. Results: A total of 4,969 individuals aged 60 years and above were randomly selected from 48 primary medical institutions in Handan. The awareness rate of hospice care in the baseline survey was 19.3% (n = 959). All included individuals were divided into two groups in accordance with their awareness of hospice care. The awareness of hospice care among participants with low educational level, living alone, and afraid of talking about death was low (p < .05). Implications for Practice: The level of awareness of hospice care among community-dwelling elderly participants is low. The influencing factors included educational level, living status, and fear of talking about death. The community-dwelling elderly participants' awareness of hospice care must be improved. It is recommended that public medical education and training should be enhanced to improve knowledge and awareness of hospice care among community-dwelling elderly residents with low educational level, living alone, and afraid of talking about death.
Subject(s)
Hospice Care , Aged , Humans , Educational Status , Fear , Independent Living , Quality of Life , Middle AgedABSTRACT
The emergence and development of radical luminescent materials is a huge breakthrough toward high-performance organic light-emitting diodes (OLEDs) without spin-statistical limits. Herein, we design a series of radicals based on tris(2,4,6-trichlorophenyl)methyl (TTM) by combining skeleton-engineering and periphery-engineering strategies, and present some insights into how different chemical modifications can modulate the chemical stability and luminescence properties of radicals by quantum chemistry methods. Firstly, through the analysis of the geometric structure changes from the lowest doublet excited state (D1) to the doublet ground state (D0) states, the emission energy differences between the BN orientation isomers are explained, and it is revealed that the radical with a smaller dihedral angle difference can more effectively suppress the geometric relaxation of the excited states and bring a higher emission energy. Meanwhile, a comparison of the excited state properties in different radicals can help us to disclose the luminescence behavior, that is, the enhanced luminescent intensity of the radical is caused by the intensity borrowing between the charge transfer (CT) state and the dark locally excited (LE) state. In addition, an efficient algorithm for calculating the internal conversion rate (kIC) is introduced and implemented, and the differences in kIC values between designed radicals are explained. More specifically, the delocalization of hole and electron wave functions can reduce nonadiabatic coupling matrix elements (NACMEs), thus hindering the non-radiative decay process. Finally, the double-regulation of chemical stability and luminescence properties was realized through the synergistic effect of skeleton-engineering and periphery-engineering, and to screen the excellent doublet emitter (BN-41-MPTTM) theoretically.
ABSTRACT
To develop novel anti-inflammatory agents, a series of new pentadienone oxime ester compounds were designed and synthesized. The structures were determined by IR, 1H NMR, 13 C NMR, and HRMS. All compounds have been screened for their anti-inflammatory activity by evaluating their inhibition against LPS-induced nitric oxide (NO) release in RAW 264.7 cell. Among them, compound 5j was found to be one of the most potent compounds in inhibiting NO and IL-6 (IC50 values were 6.66 µM and 5.07 µM, respectively). Preliminary mechanism studies show that title compound 5j could significantly suppress expressions of nitric oxide synthase, COX-2, and NO, IL-6 through Toll-like receptor 4/mitogen-activated protein kinases/NF-κB signalling pathway. These data support further studies to assess rational design of more efficient pentadienone oxime ester derivatives with anti-inflammatory activity in the future.
Subject(s)
Anti-Inflammatory Agents, Non-Steroidal/pharmacology , Esters/pharmacology , Ketones/pharmacology , Lipopolysaccharides/antagonists & inhibitors , Nitric Oxide/antagonists & inhibitors , Oximes/pharmacology , Animals , Anti-Inflammatory Agents, Non-Steroidal/chemical synthesis , Anti-Inflammatory Agents, Non-Steroidal/chemistry , Dose-Response Relationship, Drug , Esters/chemistry , Ketones/chemistry , Lipopolysaccharides/pharmacology , Mice , Molecular Structure , Nitric Oxide/biosynthesis , Oximes/chemistry , RAW 264.7 Cells , Structure-Activity RelationshipABSTRACT
Tea is a popular drink around the world. It is also one of the sources of metal intake. The objectives of this study were to assess chromium (Cr) intake from popular green, oolong, black and Pu-erh tea. In total, 128 Chinese made teas were analysed and concentration differences among four types of tea were explored. Black tea contained highest total Cr, which varied between 0.63 and 17.60 mg/kg. The lowest content was found in the green tea samples, between 0.26 and 1.30 mg/kg. Cr(III) and Cr(VI) in black tea were higher than in other types of tea. Cr(III), Cr(VI) and total Cr concentration in different tea infusions were also analysed. The results suggest that drinking tea is an effective way for Cr intake and the risk of adults and children being chronically intoxicated by tea infusions is low.
Subject(s)
Chromium/chemistry , Tea/chemistry , Adult , Child , China , Food Analysis , Food Contamination , HumansABSTRACT
This paper reported the coupling technique of Ag island film-enhanced fluorescence with rare earth co-luminescence effect of Tb-Gd-sodium dodecyl benzene sulfonate (SDBS)-protein system. While the collagen is used as the separator between Ag island film and the fluorophore because it not only can decrease the fluorescence of the blank, but also can promote the adsorption of other proteins and change the conformation of the protein. The effects of Ag island film on both the fluorescence and resonance energy transfer process of Tb-Gd-SDBS-protein system are studied, finding that Ag island film can enhance the energy transfer efficiency of this system, resulting in fluorescence enhancement about tenfold compared with this system without Ag island film. Therefore, this technique is used for the detection of proteins as low as 0.72 ng/mL for BSA and 1.3 ng/mL for HSA. In addition, Ag island film can also change the energy transfer process of Tb-SDBS-protein system.
Subject(s)
Benzenesulfonates/chemistry , Gadolinium/chemistry , Luminescence , Proteins/analysis , Silver/chemistry , Terbium/chemistry , Animals , Cattle , Fluorescence Resonance Energy Transfer , Sensitivity and SpecificityABSTRACT
Protein disulfide isomerase-related protein A (PRPA) was highly expressed (about 34%) in Escherichia coli by inserting the whole PRPA cDNA into the vector pET23b. After expression, the purified protein was acquired through ammonium fractional precipitation and Bio-Rex 70 chromatography. PRPA shows low disulfide isomerase activity (only about 1/250 of that of hPDI), decreases the reactivation yield of denatured and reduced lysozyme either in redox and non-redox Hepes buffer or redox PBS buffer and facilitates the aggregation of denatured and reduced lysozyme. Fluorescence spectra of PRPA indicate that PRPA has more hydrophobic groups at surface than that of hPDI, and which can be used to explain why PRPA has anti-chaperone activity during the refolding of denatured and reduced lysozyme.