The development of nonfullerene acceptors (NFAs), represented by ITIC, has contributed to improving the power conversion efficiency (PCE) of organic solar cells (OSCs). Although tuning the electronic ...structures to reduce the exciton binding energy (Eb) is considered to promote photocharge generation, a rational molecular design for NFAs has not been established. In this study, we designed and developed two ITIC‐based NFAs bearing spiro‐substituted bithiophene or biphenyl units (named SpiroT‐DCI and SpiroF‐DCI) to tune the frontier molecular orbital (FMO) distribution of NFAs. While the highest occupied molecular orbitals (HOMOs) of SpiroF‐DCI and ITIC are delocalized in the main π‐conjugated framework, the HOMO of SpiroT‐DCI is distributed on the bithiophene unit. Reflecting this difference, SpiroT‐DCI exhibits a smaller Eb than either SpiroF‐DCI or ITIC, and exhibits greater external quantum efficiency in single‐component OSCs. Furthermore, SpiroT‐DCI shows improved PCEs for bulk‐heterojunction OSCs with a donor of PBDB‐T, compared with that of either SpiroT‐DCI or ITIC. Time‐resolved spectroscopy measurements show that the photo‐induced intermolecular charge separation is effective even in pristine SpiroT‐DCI films. This study highlights the introduction of spiro‐substituted bithiophene units that are effective in tuning the FMOs of ITIC, which is desirable for reducing the Eb and improving the PCE in OSCs.
There is a growing body of evidence regarding cell competition between normal and mutant mammalian cells, which suggest that it may play a defensive role in the early phase of carcinogenesis. In ...vitro study in the past has shown that overexpression of vimentin in normal epithelial cells at the contact surface with transformed cells is essential for the cell competition involved in epithelial defense against cancer. In this study, we attempted to examine cell competition in human tissue in vivo by investigating surgically resected human fallopian tubes that contain p53 signatures and serous tubal intraepithelial lesions (STILs), a linear expansion of p53-immunopositive/TP53 mutant tubal epithelial cells that are considered as precursors of pelvic high grade serous carcinoma. Immunofluorescence double staining for p53 and the cell competition marker vimentin was performed in 21 sections of human fallopian tube tissue containing 17 p53 signatures and 4 STILs. The intensities of vimentin expression at the interface between p53-positive cells at the end of the p53 signature/STIL and adjacent p53-negative normal tubal epithelial cells were compared with the background tubal epithelium. As a result, the average vimentin intensity at the interfaces relative to the background intensity was 1.076 (95% CI, 0.9412 - 1.211 for p53 signature and 0.9790 (95% CI, 0.7206 - 1.237) for STIL. Thus, it can be concluded that overexpression of the cell competition marker vimentin are not observed in human tissue with TP53 alterations.
A series of electron‐deficient π‐conjugated systems with 4,9‐dihydro‐s‐indaceno2,1‐d:6,5‐d′dithiazole‐4,9‐dione‐based structures and fluorinated acyl groups as the terminal units have been designed ...and synthesized for application as organic field‐effect transistor (OFET) materials. The thermal, photophysical, and electrochemical properties and OFET performance of the synthesized compounds were investigated. OFET evaluation revealed that all compounds exhibited typical electron‐transporting characteristics, and electron mobilities up to 0.26 cm2 V−1 s−1 could be achieved. The air stabilities of OFET operation were dependent on the nature of the compounds and were investigated by X‐ray diffraction and atomic force microscopy. The terminal units had a great influence not only on the molecular properties, but also on the film‐forming properties and OFET performance.
Semiconducting materials: Electron‐transporting π‐conjugated compounds containing 4,9‐dihydro‐s‐indaceno2,1‐d:6,5‐d′dithiazole‐4,9‐dione were synthesized as candidates for organic semiconducting materials (see figure). Their properties were investigated by photophysical and electrochemical measurements. Field‐effect transistor devices based on these compounds showed good n‐type performance. The influence of the chemical structures on the device performance was investigated by X‐ray diffraction and atomic force microscopy.
The development of nonfullerene acceptors (NFAs), represented by ITIC, has contributed to improving the power conversion efficiency (PCE) of organic solar cells (OSCs). Although tuning the electronic ...structures to reduce the exciton binding energy (Eb) is considered to promote photocharge generation, a rational molecular design for NFAs has not been established. In this study, we designed and developed two ITIC‐based NFAs bearing spiro‐substituted bithiophene or biphenyl units (named SpiroT‐DCI and SpiroF‐DCI) to tune the frontier molecular orbital (FMO) distribution of NFAs. While the highest occupied molecular orbitals (HOMOs) of SpiroF‐DCI and ITIC are delocalized in the main π‐conjugated framework, the HOMO of SpiroT‐DCI is distributed on the bithiophene unit. Reflecting this difference, SpiroT‐DCI exhibits a smaller Eb than either SpiroF‐DCI or ITIC, and exhibits greater external quantum efficiency in single‐component OSCs. Furthermore, SpiroT‐DCI shows improved PCEs for bulk‐heterojunction OSCs with a donor of PBDB‐T, compared with that of either SpiroT‐DCI or ITIC. Time‐resolved spectroscopy measurements show that the photo‐induced intermolecular charge separation is effective even in pristine SpiroT‐DCI films. This study highlights the introduction of spiro‐substituted bithiophene units that are effective in tuning the FMOs of ITIC, which is desirable for reducing the Eb and improving the PCE in OSCs.
To evaluate and characterize the etiopathogenesis of the fusarial onychomycosis in an ex vivo study through fragments of sterile human nail, without the addition of any nutritional source.
The ...infection and invasion of Fusarium oxysporum in the nail were evaluated by scanning electron microscopy (SEM), CFU, matrix, histopathology and Fourier Transform Infrared Spectrometer coupled to an equipment with diamond accessory (FTIR-ATR).
F. oxysporum infected and invaded across the nail, regardless of application face. However, the dorsal nail surface was the strongest barrier, while the ventral was more vulnerable to infection and invasion process. The fungal-nail interaction resulted in the formation of a dense biofilm.
F. oxysporum infect and invade the healthy human nail, resulting in biofilm formation. Therefore, F. oxysporum is likely a primary onychomycosis agent.
A series of electron-deficient π-conjugated systems with 4,9-dihydro-s-indaceno2,1-d:6,5-d'dithiazole-4,9-dione-based structures and fluorinated acyl groups as the terminal units have been designed ...and synthesized for application as organic field-effect transistor (OFET) materials. The thermal, photophysical, and electrochemical properties and OFET performance of the synthesized compounds were investigated. OFET evaluation revealed that all compounds exhibited typical electron-transporting characteristics, and electron mobilities up to 0.26cm(2) V(-1) s(-1) could be achieved. The air stabilities of OFET operation were dependent on the nature of the compounds and were investigated by X-ray diffraction and atomic force microscopy. The terminal units had a great influence not only on the molecular properties, but also on the film-forming properties and OFET performance.
A series of electron-deficient π-conjugated systems with 4,9-dihydro-s-indaceno2,1-d:6,5-d'dithiazole-4,9-dione-based structures and fluorinated acyl groups as the terminal units have been designed ...and synthesized for application as organic field-effect transistor (OFET) materials. The thermal, photophysical, and electrochemical properties and OFET performance of the synthesized compounds were investigated. OFET evaluation revealed that all compounds exhibited typical electron-transporting characteristics, and electron mobilities up to 0.26cm2V-1s-1 could be achieved. The air stabilities of OFET operation were dependent on the nature of the compounds and were investigated by X-ray diffraction and atomic force microscopy. The terminal units had a great influence not only on the molecular properties, but also on the film-forming properties and OFET performance.
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