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In this work, the authors realize stable and highly efficient wide‐bandgap perovskite solar cells that promise high power conversion efficiencies (PCE) and are likely to play a key role in next generation multi‐junction photovoltaics (PV). This work reports on wide‐bandgap (≈1.72 eV) perovskite solar cells exhibiting stable PCEs of up to 19.4% and a remarkably high open‐circuit voltage (VOC) of 1.31 V. The VOC‐to‐bandgap ratio is the highest reported for wide‐bandgap organic?inorganic hybrid perovskite solar cells and the VOC also exceeds 90% of the theoretical maximum, defined by the Shockley–Queisser limit. This advance is based on creating a hybrid 2D/3D perovskite heterostructure. By spin coating n‐butylammonium bromide on the double‐cation perovskite absorber layer, a thin 2D Ruddlesden–Popper perovskite layer of intermediate phases is formed, which mitigates nonradiative recombination in the perovskite absorber layer. As a result, VOC is enhanced by 80 mV.  相似文献   
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International Journal of Peptide Research and Therapeutics - Tumor cells in breast cancer are immunogenic and express proteins that can induce immune responses. One important antigen is human...  相似文献   
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International Journal of Peptide Research and Therapeutics - One of the main problems in tumor therapy is immunosuppressive microenvironment of the tumor. To overcome this, we assessed targeted...  相似文献   
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Neurochemical Research - Alzheimer’s disease (AD) is associated with neural oxidative stress and inflammation, and it is assumed to affect more women than men with unknown mechanisms....  相似文献   
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International Journal of Peptide Research and Therapeutics - Viruses of the picornavirus-like supercluster mainly achieve cleavage of polyproteins into mature proteins through viral 3-chymotrypsin...  相似文献   
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Human dermal fibroblasts (HDFs) are a potential source of somatic cells for genetic manipulation and tissue engineering. Confirmation of cytogenetic stability of these cells is an essential step for cell nuclear transfer and generation of a suitable and functional induced pluripotent stem cells line. HDF cells were isolated and cultured from human foreskin samples. Cytogenetic stability of these cells was evaluated in early (3–4) and late (10–15) passages using karyotype test and alkaline comet assay techniques. HDF cells in early and late passages showed normal karyotype but by comet assay abnormality and DNA damages in late passages of HDFs were observed. Also, the parameters of alkaline comet assay in early passages of HDFs compared with late passages and positive control groups more significantly were different (p < 0.05). These findings indicate that single-strand breaks or DNA damage after many passages may have occurred in HDF cells. Our results demonstrate that only early passages of HDF cells maintain cytogenetic stability and are good candidates for gene reprogramming. In conclusion, karyotype testing alone can not be used for detection of all signs of cytogenetic abnormality and DNA damages of cells. So, for precise evaluation of DNA damage and cytogenetic instability of fibroblast cells comet assay and karyotype techniques could complement each other.  相似文献   
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Infection of human B cells with Epstein-Barr virus (EBV) induces polyclonal activation in almost all infected cells, but a small proportion of infected cells are transformed to immortalized lymphoblastoid cell lines. Since B cells are activated also by CD40 ligand (CD40L) and Toll-like receptor (TLR) agonists via a similar signaling pathway, it is likely that costimulation through these molecules could result in synergistic enhancement of the transformation efficiency of EBV. In this study, the stimulatory effect of TLR7/8 (R848), TLR9 (CpG) agonists and/or CD40L on transformation efficiency of EBV in normal human B cells was assessed using the limiting dilution assay. Costimulation of peripheral blood mononuclear cells (PBMCs) with CpG and R848, but not CD40L, increased significantly the frequency of EBV transformed B cells (p < 0.001). Neither synergistic nor additive effects were observed between TLR agonists and CD40L and also TLR7/8 and TLR9 agonists. Costimulation with R848, CpG and CD40L enhanced the proliferative response of B cells infected with EBV. This effect was more evident when enriched B cells were employed, compared to PBMCs. The promoting effect of TLR agonists stimulation, implies that EBV may take advantage of the genes induced by the TLR stimulation pathway for viral latency and oncogenesis.  相似文献   
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A density functional theory investigation of adsorption of monomer, dimer and trimer forms of pyrrole on the outer surface of zigzag (7,0) single-walled carbon nanotube (SWCNT) has been reported. Geometries of the complexes were optimized using the M06-2X functional and the 6-31G(d,p) basis set. Moreover, 6-311G(d,p), cc-pVDZ and cc-pVTZ basis sets were used for the adsorption energy calculation and such energies were corrected for the basis set superposition error. Vertical ionization potential and electron affinity of the investigated system were also computed. The interaction of polypyrrole on the SWCNT surface is characterized by the stacking interaction. Adsorption (binding) energy of pyrrole on the SWCNT surface is weak, but such energy increases with the number of monomer units in the pyrrole oligomer. In the SWCNT-pyrrole complexes, the oxidation and reduction processes will take place only at the SWCNT. The influence of larger unit on the electronic properties of the complex has been detailed.  相似文献   
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