Passivation of electronic defects at the surface and grain boundaries of perovskite materials has become one of the most important strategies to suppress charge recombination in both polycrystalline ...and single-crystalline perovskite solar cells. Although many passivation molecules have been reported, it remains very unclear regarding the passivation mechanisms of various functional groups. Here, we systematically engineer the structures of passivation molecular functional groups, including carboxyl, amine, isopropyl, phenethyl, and tert-butylphenethyl groups, and study their passivation capability to perovskites. It reveals the carboxyl and amine groups would heal charged defects via electrostatic interactions, and the neutral iodine related defects can be reduced by the aromatic structures. The judicious control of the interaction between perovskite and molecules can further realize grain boundary passivation, including those that are deep toward substrates. Understanding of the underlining mechanisms allows us to design a new passivation molecule, D-4-tert-butylphenylalanine, yielding high-performance p-i-structure solar cells with a stabilized efficiency of 21.4%. The open-circuit voltage (V OC) of a device with an optical bandgap of 1.57 eV for the perovskite layer reaches 1.23 V, corresponding to a record small V OC deficit of 0.34 V. Our findings provide a guidance for future design of new passivation molecules to realize multiple facets applications in perovskite electronics.
Phosphorene, a monolayer of black phosphorus, is promising for nanoelectronic applications not only because it is a natural p-type semiconductor but also because it possesses a layer-number-dependent ...direct bandgap (in the range of 0.3 to 1.5 eV). On basis of the density functional theory calculations, we investigate electronic properties of the bilayer phosphorene with different stacking orders. We find that the direct bandgap of the bilayers can vary from 0.78 to 1.04 eV with three different stacking orders. In addition, a vertical electric field can further reduce the bandgap to 0.56 eV (at the field strength 0.5 V/Å). More importantly, we find that when a monolayer of MoS2 is superimposed with the p-type AA- or AB-stacked bilayer phosphorene, the combined trilayer can be an effective solar-cell material with type-II heterojunction alignment. The power conversion efficiency is predicted to be ∼18 or 16% with AA- or AB-stacked bilayer phosphorene, higher than reported efficiencies of the state-of-the-art trilayer graphene/transition metal dichalcogenide solar cells.
Diabetes is a disorder of glucose metabolism, and over 90% are type 2 diabetes. Diabetic cardiomyopathy (DCM) is one of the type 2 diabetes complications, usually accompanied by changes in myocardial ...structure and function, together with cardiomyocyte apoptosis. Our study investigated the effect of curcumin on regulating oxidative stress (OS) and apoptosis in DCM. In vivo, diabetes was induced in an experimental rat model by streptozoticin (STZ) together with high‐glucose and high‐fat (HG/HF) diet feeding. In vitro, H9c2 cardiomyocytes were cultured with high‐glucose and saturated free fatty acid palmitate. Curcumin was orally or directly administered to rats or cells, respectively. Streptozoticin ‐induced diabetic rats showed metabolism abnormalities and elevated markers of OS (superoxide dismutase SOD, malondialdehyde MDA, gp91phox, Cyt‐Cyto C), enhanced cell apoptosis (Bax/Bcl‐2, Cleaved caspase‐3, TUNEL‐positive cells), together with reduced Akt phosphorylation and increased Foxo1 acetylation. Curcumin attenuated the myocardial dysfunction, OS and apoptosis in the heart of diabetic rats. Curcumin treatment also enhanced phosphorylation of Akt and inhibited acetylation of Foxo1. These results strongly suggest that apoptosis was increased in the heart of diabetic rats, and curcumin played a role in diabetic cardiomyopathy treatment by modulating the Sirt1‐Foxo1 and PI3K‐Akt pathways.
A new two‐dimensional (2D) layered material, namely, titanium trisulfide (TiS3) monolayer, is predicted to possess novel electronic properties. Ab initio calculations show that the perfect TiS3 ...monolayer is a direct‐gap semiconductor with a bandgap of 1.02 eV, close to that of bulk silicon, and with high carrier mobility. More remarkably, the in‐plane electron mobility of the 2D TiS3 is highly anisotropic, amounting to about 10 000 cm2 V−1 s−1 in the b direction, which is higher than that of the MoS2 monolayer, whereas the hole mobility is about two orders of magnitude lower. Furthermore, TiS3 possesses lower cleavage energy than graphite, suggesting easy exfoliation for TiS3. Both dynamical and thermal stability of the TiS3 monolayer is examined by phonon‐spectrum calculation and Born–Oppenheimer molecular dynamics simulation. The desired electronic properties render the TiS3 monolayer a promising 2D atomic‐layer material for applications in future nanoelectronics.
New semiconductor: A titanium trisulfide monolayer is predicted to be a direct‐gap semiconductor with ultrahigh electron mobility (≈104 cm2 V−1 s−1), which is higher than that of MoS2 and phosphorene. The monolayer can be exfoliated from its bulk phase due to the lower exfoliation energy compared to graphite.
In recent years, the problem of oily sewage has seriously affected the ecological environment and human health. Thus, we prepared a novel biodegradable poly (lactic acid) (PLA) membrane with ...antibacterial property and oil–water separation function via electrospinning method. First, the matter of silver ion glass microbeads (AgGB) loaded with layered double hydroxides (LDHs) and the LDH@AgGB modified with 3‐triethoxysilyl‐1‐Propanamine (APTES) were synthesized. Then, the LDH@AgGB were blended with PLA to prepare PLA/LDH@AgGB composite. And the PLA nanofibrous membranes were electrospun. The results showed that APTES could significantly improve the dispersion and compatibility of LDH@AgGB in PLA matrix. The addition of A‐LDH@AgGB could greatly improve the crystallinity, and control the porosity and pore‐size of PLA membranes. The maximum water contact angle of the PLA membranes could reach to 109.31°, while the oil contact angle of the PLA membranes decreased to 0° resulting in a high oil absorption capacity, and fast oil absorption rate performance. Meanwhile, the PLA membrane had efficient antibacterial property against Escherichia coli. The reported novel LDH@AgGB and its PLA composite membrane provided a method for designing and preparing environmental‐friendly, high‐performance materials with both excellent antibacterial property and oil–water separation.
MicroRNAs (miRNAs, miRs) have emerged as important post-transcriptional regulators in various cancers. miR-543 has been reported to play critical roles in hepatocellular carcinoma and colorectal ...cancer, however, the role of miR-543 in the pathogenesis of prostate cancer has not been fully understood.
Expression of miR-543 and Raf Kinase Inhibitory Protein (RKIP) in clinical prostate cancer specimens, two prostate cancer cell lines, namely LNCAP and C4-2B, were determined. The effects of miR-543 on proliferation and metastasis of tumor cells were also investigated with both in vitro and in vivo studies.
miR-543 was found to be negatively correlated with RKIP expression in clinical tumor samples and was significantly upregulated in metastatic prostate cancer cell line C4-2B compared with parental LNCAP cells. Further studies identified RKIP as a direct target of miR-543. Overexpression of miR-543 downregulated RKIP expression and promoted the proliferation and metastasis of cancer cells, whereas knockdown of miR-543 increased expression of RKIP and suppressed the proliferation and metastasis of cancer cells in vitro and in vivo.
Our study demonstrates that miR-543 promotes the proliferation and metastasis of prostate cancer via targeting RKIP.
This study unpacks the environmental and social dimensions of supplier responsibility and links each dimension to distinct drivers. Using stakeholder theory and the relational view, we distinguish ...between two main drivers: stakeholder pressures (i.e., from regulatory agencies, buying firms, and nongovernmental organizations) and relational mechanisms offered by multinational companies (MNCs) (i.e., lean trainings and relational capital). We used a multi‐method research design to study how these drivers uniquely influence supplier responsibility in an emerging‐country context. An in‐depth case study with Philips Lighting and 10 of its Chinese suppliers reveals causal inferences that link stakeholder and relational drivers with each responsibility dimension (environmental vs. social). Audit and survey data from Philips Lighting's 134 Chinese suppliers, complemented with four archival databases, bolster these inferences. Overall, the results show that supplier environmental responsibility can be fostered through both stakeholder pressures and relational drivers; whereas, supplier social responsibility is much harder to address. The integrated methods offer a fuller, more comprehensive understanding of the specifics of supplier responsibility in China and also provide recommendations for MNCs that seek to improve it.
Atomically precise metal nanoclusters (NCs) represent an emerging sector of light-harvesting antennas by virtue of peculiar atomic stacking fashion, quantum confinement effect, and molecular-like ...discrete energy band structure. Nevertheless, precise control of charge carriers over metal NCs has yet to be achieved by the short carrier lifetime and intrinsic instability of metal NCs, which renders the complexity of metal NCs-based photosystems with photoredox mechanisms remaining elusive. Herein, fine tuning of charge migration over metal NCs is demonstrated by constructing directional charge transfer channels in multilayered heterostructure enabled by a facile layer-by-layer (LbL) assembly approach, wherein oppositely charged branched poly-ethylenimine (BPEI) and glutathione (GSH)-capped gold NCs Au
NCs, Au
(GSH)
NCs are alternately deposited on the metal oxide (MOs: TiO
, WO
, Fe
O
) substrates. TheAu
(Au
) NCs layer serves as light-harvesting antennas for engendering charge carriers, andBPEI interim layer uniformly intercalated at the interface of Au
NCs layer constitutes the tandem hole transport channel for motivating the charge transfer cascade, resulting in the considerably enhanced photoelectrochemical water oxidation performances. Besides, poor photo-stability of Au
NCs is surmounted by stimulating the hole transfer kinetics process.
Long noncoding RNA (lncRNA) have critical roles in various pathophysiological processes, and are frequently dysregulated in many diseases, particularly in cancer. The lncRNA glypican 3 antisense ...transcript 1 (GPC3‐AS1) has been reported to be a potential biomarker for hepatocellular carcinoma (HCC) screening. However, the exact biological functions of GPC3‐AS1 in HCC, and its roles and regulation mechanisms regarding GPC3 are still unknown. In this study, we observed a significant upregulation of GPC3‐AS1 in HCC. Increased expression of GPC3‐AS1 was associated with α‐fetoprotein, tumor size, microvascular invasion, encapsulation, Barcelona Clinic Liver Cancer stage, and worse prognosis of HCC patients. Furthermore, we found that GPC3‐AS1 physically associated with P300/CBP‐associated factor and recruited it to the GPC3 gene body region, consequently inducing an increase in euchromatic histone marks and activating GPC3 transcription. GPC3‐AS1 expression was strongly correlated with GPC3 in HCC tissues. Gain‐of‐function and loss‐of‐function analyses showed that GPC3‐AS1 overexpression enhanced HCC cell proliferation and migration in vitro and xenograft tumor growth in vivo. GPC3‐AS1 knockdown inhibited HCC cell proliferation and migration. Moreover, the effects of GPC3‐AS1 on HCC cell proliferation and migration were dependent on the upregulation of GPC3. Collectively, our studies indicate that GPC3‐AS1 significantly promotes HCC progression via epigenetically activating GPC3, and identifies GPC3‐AS1 as a potential therapeutic target for HCC.
The long noncoding RNA GPC3‐AS1 is significantly upregulated in hepatocellular carcinoma (HCC) and indicates poor prognosis of HCC patients. GPC3‐AS1 physically associates with P300/CBP‐associated factor (PCAF) and recruits it to the GPC3 gene body region, consequently inducing an increase in euchromatic histone marks and activating GPC3 transcription. GPC3‐AS1 overexpression enhances HCC cell proliferation and migration in vitro and xenograft tumour growth in vivo.
In the strong deflection gravitational lensing, given the fact that a black-bounce, traversable wormhole is indistinguishable from a Schwarzschild black hole and is loosely tested by the Event ...Horizon Telescope, we intensively study its signatures of weak deflection gravitational lensing in light of the tremendous progress made by the new generation of the near-infrared interferometer GRAVITY. After obtaining its observables, which are the positions, magnitudes of brightness, centroid, and differential time delay between the lensed images, we investigate three astrophysical scenarios: an orbiting star lensed by the Galactic Center Sgr A*, a microlensed star in the Galactic bulge, and microlensing by a nearby lens. We find that the measurements of the observables of Sgr A* provide a promising way to test the black-bounce, traversable wormhole spacetime. GRAVITY can resolve the angular separation, the angular difference, and the time delay between the two lensed images by Sgr A*, and it can marginally detect their deviations from those of the Schwarzschild black hole. The brightness difference between the images and its deviation might be measured by a dedicated space telescope. In the near future, we expect that such a spacetime would be more robustly tested with the weak deflection gravitational lensing by further improved and upgraded GRAVITY+.
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