Dopant-Free Hole-Transporting Material Based on Poly(2,7-(9,9-bis(N,N-di-p-methoxylphenylamine)-4-phenyl))-fluorene for High-Performance Air-Processed Inverted Perovskite Solar Cells.

It is a great challenge to develop low-cost and dopant-free polymer hole-transporting materials (HTM) for PSCs, especially for efficient air-processed inverted (p-i-n) planar PSCs. A new homopolymer HTM, poly(2,7-(9,9-bis(N,N-di-p-methoxylphenyl amine)-4-phenyl))-fluorene (denoted as PFTPA), with appropriate photo-electrochemical, opto-electronic and thermal stability, was designed and synthesized in two steps to meet this challenge. By employing PFTPA as dopant-free hole-transport layer in air-processed inverted PSCs, a champion power conversion efficiency (PCE) of up to 16.82% (0.1 cm2) was achieved, much superior to that of commercial HTM PEDOT:PSS (13.8%) under the same conditions. Such a superiority is attributed to the well-aligned energy levels, improved morphology, and efficient hole-transporting, as well as hole-extraction characteristics at the perovskite/HTM interface. In particular, these PFTPA-based PSCs fabricated in the air atmosphere maintain a long-term stability of 91% under ambient air conditions for 1000 h. Finally, PFTPA as the dopant-free HTM was also fabricated the slot-die coated perovskite device through the same fabrication condition, and a maximum PCE of 13.84% was obtained. Our study demonstrated that the low-cost and facile homopolymer PFTPA as the dopant-free HTM are potential candidates for large-scale production perovskite solar cell.

Inverted perovskite solar cells using dimethylacridine-based dopants.

Doping of perovskite semiconductors1 and passivation of their grain boundaries2 remain challenging but essential for advancing high-efficiency perovskite solar cells. Particularly, it is crucial to build perovskite/indium tin oxide (ITO) Schottky contact based inverted devices without predepositing a layer of hole-transport material3-5. Here we report a dimethylacridine-based molecular doping process used to construct a well-matched p-perovskite/ITO contact, along with all-round passivation of grain boundaries, achieving a certified power conversion efficiency (PCE) of 25.39%. The molecules are shown to be extruded from the precursor solution to the grain boundaries and the bottom of the film surface in the chlorobenzene-quenched crystallization process, which we call a molecule-extrusion process. The core coordination complex between the deprotonated phosphonic acid group of the molecule and lead polyiodide of perovskite is responsible for both mechanical absorption and electronic charge transfer, and leads to p-type doping of the perovskite film. We created an efficient device with a PCE of 25.86% (reverse scan) and that maintained 96.6% of initial PCE after 1,000 h of light soaking.

Every individual makes a difference: A trinity derived from linking individual brain morphometry, connectivity and mentalising ability.

Mentalising ability, indexed as the ability to understand others' beliefs, feelings, intentions, thoughts and traits, is a pivotal and fundamental component of human social cognition. However, considering the multifaceted nature of mentalising ability, little research has focused on characterising individual differences in different mentalising components. And even less research has been devoted to investigating how the variance in the structural and functional patterns of the amygdala and hippocampus, two vital subcortical regions of the "social brain", are related to inter-individual variability in mentalising ability. Here, as a first step toward filling these gaps, we exploited inter-subject representational similarity analysis (IS-RSA) to assess relationships between amygdala and hippocampal morphometry (surface-based multivariate morphometry statistics, MMS), connectivity (resting-state functional connectivity, rs-FC) and mentalising ability (interactive mentalisation questionnaire [IMQ] scores) across the participants ( N = 24 ). In IS-RSA, we proposed a novel pipeline, that is, computing patching and pooling operations-based surface distance (CPP-SD), to obtain a decent representation for high-dimensional MMS data. On this basis, we found significant correlations (i.e., second-order isomorphisms) between these three distinct modalities, indicating that a trinity existed in idiosyncratic patterns of brain morphometry, connectivity and mentalising ability. Notably, a region-related mentalising specificity emerged from these associations: self-self and self-other mentalisation are more related to the hippocampus, while other-self mentalisation shows a closer link with the amygdala. Furthermore, by utilising the dyadic regression analysis, we observed significant interactions such that subject pairs with similar morphometry had even greater mentalising similarity if they were also similar in rs-FC. Altogether, we demonstrated the feasibility and illustrated the promise of using IS-RSA to study individual differences, deepening our understanding of how individual brains give rise to their mentalising abilities.

Simple and robust phenoxazine phosphonic acid molecules as self-assembled hole selective contacts for high-performance inverted perovskite solar cells.

For inverted perovskite solar cells (PSCs), the interfacial defects and mismatched energy levels between the perovskite absorber and charge-selective layer restrain the further improvement of photovoltaic performance. Interfacial modification is a powerful tool for defect passivation and energy level turning by developing new charge-selective materials. Herein, we report three new molecules, 2BrCzPA, 2BrPTZPA, and 2BrPXZPA as self-assembled hole selective contacts (SA-HSCs) by an economical and efficient synthetic procedure. Benefiting from the stronger electron-donating ability of phenothiazine and phenoxazine compared to that of carbazole, 2BrPTZPA and 2BrPXZPA showed more matched energy levels and decreased energy loss. In addition, the ITO substrate coated with 2BrPTZPA and 2BrPXZPA could induce higher-quality perovskite crystal growth without obvious grain boundaries in the vertical direction. Consequently, the corresponding inverted PSCs with decreased trap state density achieved high power convention efficiencies (PCEs) of 22.06% and 22.93% (certified 22.38%) for 2BrPTZPA and 2BrPXZPA, respectively. Furthermore, the 2BrPXZPA-based device with encapsulation retained 97% of the initial efficiency after 600 h of maximum power point tracking under one sun continuous illumination. Finally, 2BrPXZPA was also used for the surface modification of NiOx, and the inverted PSC based on the NiOx/2BrPXZPA bilayer achieved a higher PCE of 23.66% with an open circuit voltage of 1.21 V. This work extends the design strategy of SA-HSCs for efficient and stable inverted PSCs and promotes the commercialization process.

Organic Long-Persistent Luminescence from a Thermally Activated Delayed Fluorescence Compound.

Organic long-persistent luminescence (OLPL) is one of the most promising methods for long-lived-emission applications. However, present room-temperature OLPL emitters are mainly based on a bimolecular exciplex system which usually needs an expensive small molecule such as 2,8-bis(diphenyl-phosphoryl)dibenzo[b,d]thiophene (PPT) as the acceptor. In this study, a new thermally activated delayed fluorescence (TADF) compound, 3-(4-(9H-carbazol-9-yl)phenyl)acenaphtho[1,2-b]pyrazine-8,9-dicarbonitrile (CzPhAP), is designed, which also shows OLPL in many well-known hosts such as PPT, 2,2',2″-(1,3,5-benzinetriyl)-tris(1-phenyl-1-H-benzimidazole) (TPBi), and poly(methyl methacrylate) (PMMA), without any exciplex formation, and its OLPL duration reaches more than 1 h at room temperature. Combining the low cost of PMMA manufacture and flexible designs of TADF molecules, pure organic, large-scale, color tunable, and low-cost room-temperature OLPL applications become possible. Moreover, it is found that the onset of the 77 K afterglow spectra from a TADF-emitter-doped film is not necessarily reliable for determining the lowest triplet state energy level. This is because in some TADF-emitter-doped films, optical excitation can generate charges (electron and holes) that can later recombine to form singlet excitons during the phosphorescence spectrum measurement. The spectrum taken in the phosphorescence time window at low temperature may consequently consist of both singlet and triplet emission.

Fine-tuning ERNIE for chest abnormal imaging signs extraction.

Chest imaging reports describe the results of chest radiography procedures. Automatic extraction of abnormal imaging signs from chest imaging reports has a pivotal role in clinical research and a wide range of downstream medical tasks. However, there are few studies on information extraction from Chinese chest imaging reports. In this paper, we formulate chest abnormal imaging sign extraction as a sequence tagging and matching problem. On this basis, we propose a transferred abnormal imaging signs extractor with pretrained ERNIE as the backbone, named EASON (fine-tuning ERNIE with CRF for Abnormal Signs ExtractiON), which can address the problem of data insufficiency. In addition, to assign the attributes (the body part and degree) to corresponding abnormal imaging signs from the results of the sequence tagging model, we design a simple but effective tag2relation algorithm based on the nature of chest imaging report text. We evaluate our method on the corpus provided by a medical big data company, and the experimental results demonstrate that our method achieves significant and consistent improvement compared to other baselines.

Ellagic acid protects ovariectomy-induced bone loss in mice by inhibiting osteoclast differentiation and bone resorption.

Osteoporosis is a devastating disease that features reduced bone quantity and microstructure, which causes fragility fracture and increases mortality, especially in the aged population. Due to the long-term side-effects of current drugs for osteoporosis, it is of importance to find other safe and effective medications. Ellagic acid (EA) is a phenolic compound found in nut galls, plant extracts, and fruits, and exhibits antioxidant and antineoplastic effects. Here, we showed that EA attenuated the formation and function of osteoclast dose-dependently. The underlying mechanism was further discovered by western blot, immunofluorescence assay, and luciferase assay, which elucidated that EA suppressed osteoclastogenesis and bone resorption mainly through attenuating receptor activator of nuclear factor-κB (NF-κB) ligand-induced NF-κB activation and extracellular signal-regulated kinase signaling pathways, accompanied by decreased protein expression of nuclear factor of activated T-cells calcineurin-dependent 1 and c-Fos. Moreover, EA inhibits osteoclast marker genes expression including Dc-stamp, Ctsk, Atp6v0d2, and Acp5. Intriguingly, we also found that EA treatment could significantly protect ovariectomy-induced bone loss in vivo. Conclusively, this study suggested that EA might have the therapeutic potentiality for preventing or treating osteoporosis.

Dehydrocostus lactone (DHC) suppresses estrogen deficiency-induced osteoporosis.

Osteoporosis is a chronic bone lytic disease, because of inadequate bone ossification and/or excessive bone resorption. Even though drugs are currently available for the treatment of osteoporosis, there remains an unmet need for the development of more specific novel agents with less adverse effects. Dehydrocostus lactone (DHC), a natural sesquiterpene lactone, was previously found to affect the differentiation of inflammatory cells by inhibiting NF-κB pathways, and garnered much interest for its anti-cancer properties via SOCS-mediated cell cycle arrest and apoptosis. As NF-κB pathway plays an essential role in osteoclast differentiation, we sought to discover the biological effects of DHC on osteoclast differentiation and resorptive activity, as well as the underlying mechanisms on these effects. Our research found that DHC inhibited RANKL-induced osteoclast differentiation, bone resorption and osteoclast specific genes expression via suppression of NF-κB and NFAT signaling pathways in vitro. We further demonstrated that DHC protected against ovariectomy (OVX)-induced bone loss in mice and the protective effect was mediated at least in part through the attenuation of NF-κB signaling pathway. Thus, this study provides insight that DHC might be used as a potential pharmacological treatment for osteoporosis.

Retraction of: A005, a novel inhibitor of phosphatidylinositol 3-kinase/mammalian target of rapamycin, prevents osteosarcoma-induced osteolysis.

Osteosarcoma is the most frequent primary bone tumor in children and adolescents. The phosphatidylinositol 3-kinase (PI3K)/mammalian target of rapamycin (mTOR) signaling pathway is an attractive anticancer target because it plays key roles in the regulation of cell growth, division and differentiation. In this study, we demonstrated high expression of PI3K/mTOR signaling pathway-related genes in patients with osteosarcoma. We thus investigated the effects of A005, a newly synthesized dual PI3K/mTOR inhibitor, on osteosarcoma cells and in a mouse xenograft tumor model. The results confirmed that A005 inhibited the proliferation, migration and invasion of human osteosarcoma cells. In addition, A005 also inhibited receptor activator of nuclear factor kappa-B ligand (RANKL)-induced osteoclast differentiation and bone resorption in vitro. Therefore, A005 was further applied to a SaOS-2 osteosarcoma-induced mouse osteolysis model. A005 inhibited tumor growth and prevented osteosarcoma-associated osteolysis via modulation of the PI3K/AKT/mTOR pathway. Overall, our results showed that A005 inhibited osteoclastogenesis and prevented osteosarcoma-induced bone osteolysis by suppressing PI3K/AKT/mTOR signaling. These findings indicated that A005 may be a promising candidate drug for the treatment of human osteosarcoma.