In cancer patients, metastasis of tumors to sentinel lymph nodes (LNs) predicts disease progression and often guides treatment decisions. The mechanisms underlying tumor LN metastasis are poorly ...understood. By using comparative transcriptomics and metabolomics analyses of primary and LN-metastatic tumors in mice, we found that LN metastasis requires that tumor cells undergo a metabolic shift toward fatty acid oxidation (FAO). Transcriptional coactivator yes-associated protein (YAP) is selectively activated in LN-metastatic tumors, leading to the up-regulation of genes in the FAO signaling pathway. Pharmacological inhibition of FAO or genetic ablation of YAP suppressed LN metastasis in mice. Several bioactive bile acids accumulated to high levels in the metastatic LNs, and these bile acids activated YAP in tumor cells, likely through the nuclear vitamin D receptor. Inhibition of FAO or YAP may merit exploration as a potential therapeutic strategy for mitigating tumor metastasis to LNs.
Multi‐resonance (MR) thermally activated delayed fluorescent (TADF) emitters are highly attractive due to their superior color purity as well as efficient light‐harvesting ability from singlets and ...triplets. However, boron and nitrogen‐based MR‐TADF emitters suffer from their strong π–π interaction owing to their rigid flat cores. Herein, a boron‐based multi‐resonance blue TADF emitter with suppressed intermolecular interaction and isomer formation is developed through a simple synthetic process by introducing meta‐xylene and meta‐phenyphenyl groups to the core. The MR‐TADF emitter, mBP‐DABNA‐Me, shows a narrowband blue emission with a peak at 467 nm, along with full width at half maximum of 28 nm, and photoluminescence quantum yield of 97%. Notably, highly efficient pure blue organic light‐emitting diode (OLED) is realized using mBP‐DABNA‐Me, showing a maximum external quantum efficiency of 24.3% and a stable blue emission with a Commission Internationale de L'Eclairage coordinate of (0.124, 0.140). The color purity of the OLED is maintained at a high doping concentration of over 20%, attributed to the suppressed intermolecular interaction between the MR emitters.
A strategic substitution of the bulky groups effectively suppresses the intermolecular interaction and the formation of isomers in mBP‐DABNA‐Me. Therefore, the mBP‐DABNA‐Me based organic light‐emitting diode exhibits an efficiency of 24.3% with a pure blue emission, color‐coordinate of (0.124, 0.140). Notably, the substituents hinder the bathochromic shift, keeping the pure blue emission even at a high concentration of 25%.
High‐efficiency phosphorescent organic light‐emitting diodes (OLEDs) doped with Ir(ppy)2(acac) bis(2‐phenylpyridine)iridium(III)‐acetylacetonate in an exciplex forming co‐host have been optically ...analyzed. This emitter has a preferred orientation with the horizontal to vertical dipole ratio of 0.77:0.23 as compared to 0.67:0.33 in the isotropic case. Theoretical analysis based on the orientation factor (Θ, the ratio of the horizontal dipoles to total dipoles) and the photoluminescence quantum yield (qPL) of the emitter predicts that the maximum external quantum efficiency (EQE) of the OLEDs with this emitter is about 30%, which matches very well with the experimental data, indicating that the electrical loss of the OLEDs is negligible and the device structure can be utilized as a platform to demonstrate the validity of optical modeling. Based on the results, the maximum EQE achievable for a certain emitting dye in a host can be predicted by just measuring qPL and Θ in a neat film on glass without the need to fabricate devices, which offers a universal plot of the maximum EQE as a function of qPL and Θ.
High‐efficiency phosphorescent organic light‐emitting diodes (OLEDs) doped with Ir(ppy)2(acac) in an exciplex forming co‐host have a preferred horizontal emitter orientation. Based on optical analysis a maximum efficiency of the OLEDs of about 30% is calculated, which matches very well with the experimental data. Furthermore, a simple method to predict the maximum efficiency achievable with a certain emitting dye in a host matrix is suggested.
YAP and TAZ play oncogenic roles in various organs, but the role of YAP/TAZ in gastric cancer remains unclear. Here, we show that YAP/TAZ activation initiates gastric tumorigenesis
and verify its ...significance in human gastric cancer. In mice, YAP/TAZ activation in the pyloric stem cell led to step-wise tumorigenesis. RNA sequencing identified MYC as a decisive target of YAP, which controls MYC at transcriptional and posttranscriptional levels. These mechanisms tightly regulated MYC in homeostatic conditions, but YAP activation altered this balance by impeding miRNA processing, causing a shift towards MYC upregulation. Pharmacologic inhibition of MYC suppressed YAP-dependent phenotypes
and
, verifying its functional role as a key mediator. Human gastric cancer samples also displayed a significant correlation between YAP and MYC. We reanalyzed human transcriptome data to verify enrichment of YAP signatures in a subpopulation of gastric cancers and found that our model closely reflected the molecular pattern of patients with high YAP activity. Overall, these results provide genetic evidence of YAP/TAZ as oncogenic initiators and drivers for gastric tumors with MYC as the key downstream mediator. These findings are also evident in human gastric cancer, emphasizing the significance of YAP/TAZ signaling in gastric carcinogenesis.
YAP/TAZ activation initiates gastric carcinogenesis with MYC as the key downstream mediator.
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Phosphorescent organic light‐emitting diodes (OLEDs) with ultimate efficiency in terms of the external quantum efficiency (EQE), driving voltage, and efficiency roll‐off are reported, making use of ...an exciplex‐forming co‐host. This exciplex‐forming co‐host system enables efficient singlet and triplet energy transfers from the host exciplex to the phosphorescent dopant because the singlet and triplet energies of the exciplex are almost identical. In addition, the system has low probability of direct trapping of charges at the dopant molecules and no charge‐injection barrier from the charge‐transport layers to the emitting layer. By combining all these factors, the OLEDs achieve a low turn‐on voltage of 2.4 V, a very high EQE of 29.1% and a very high power efficiency of 124 lm W−1. In addition, the OLEDs achieve an extremely low efficiency roll‐off. The EQE of the optimized OLED is maintained at more than 27.8%, up to 10 000 cd m−2.
Using an exciplex‐forming co‐host, an organic light‐emitting diode (OLED) with ultimate efficiency is produced. The OLED has a low turn‐on voltage of 2.4 V, a very high external quantum efficiency (EQE) of 29.1%, a very high power efficiency of 124 lm W−1, and an extremely low efficiency roll‐off. The EQE of the optimized OLED is maintained at more than 27.8%, up to 10 000 cd m−2.
A multichannel/multicolor visible light communication (VLC) system using entirely organic components, including organic light emitting diodes (OLEDs) and organic photodiodes (OPDs), is developed to ...demonstrate indoor lighting applications where the integration of OLEDs and OPDs has significant potential. To achieve this, tricolor (Red/Green/Blue(R/G/B))‐selective OPD arrays for the receiver and tricolor OLED arrays for the emitter are developed. For (R/G/B)‐selective OPDs, a Fabry–Pérot electrode to enhance color selectivity and a thick junction structure to effectively accommodate a wide range of driving voltages are introduced. For tricolor OLEDs, fluorescent‐emitting materials are used to enhance the operating frequency in addition to introducing a cavity structure to achieve narrow emission. Utilizing these spectrally refined tricolor OPDs/OLEDs, a VLC system is designed for indoor lighting applications, and a systematic analysis of their signal‐to‐interference ratio dependence on the distance or angle between the transmitter and receiver is performed. The study's findings indicate the importance of emission angle‐dependent wavelength shift of the OLED and the luminosity function, which varies with wavelength, in the R/G/B mixed‐white‐light‐based VLC systems. Finally, the feasibility of VLC using tricolor OPDs/OLEDs in the real‐life context of indoor white‐color lighting is demonstrated, showing that the transmitted data patterns well‐matched the received data patterns.
A visible light communication platform using (R/G/B)‐selective organic photodiode arrays as receivers and (R/G/B) organic light‐emitting diodes as emitters is developed and analyzed to study how the geometry effect of each organic receiver and emitter affects data transmission. Based on this, the first organic material‐based white‐light optical communication system is demonstrated.
The Hippo pathway regulates the self-renewal and differentiation of various adult stem cells, but its role in cell fate determination and differentiation during liver development remains unclear. ...Here we report that the Hippo pathway controls liver cell lineage specification and proliferation separately from Notch signalling, using mice and primary hepatoblasts with liver-specific knockout of Lats1 and Lats2 kinase, the direct upstream regulators of YAP and TAZ. During and after liver development, the activation of YAP/TAZ induced by loss of Lats1/2 forces hepatoblasts or hepatocytes to commit to the biliary epithelial cell (BEC) lineage. It increases BEC and fibroblast proliferation by up-regulating TGFβ signalling, but suppresses hepatoblast to hepatocyte differentiation by repressing Hnf4α expression. Notably, oncogenic YAP/TAZ activation in hepatocytes induces massive p53-dependent cell senescence/death. Together, our results reveal that YAP/TAZ activity levels govern liver cell differentiation and proliferation in a context-dependent manner.
Abstract
Nonradiative recombination rate that consists of dislocation‐related nonradiative recombination rate (
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0
) and surface recombination rate (
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s
) is one of the major parameters determining ...the performance of microlight‐emitting diodes (µLEDs). Recent demonstrations improving the efficiency of blue InGaN or red AlGaInP µLEDs using specific methods such as atomic layer deposition or chemical treatment confirm the suppression of
A
s
. However, it is hardly found that those methods effectively improve the efficiency of red InGaN µLEDs so far. Here, it is discovered that the dislocation leads to an ineffective
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s
. First, an intrinsic
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s
degrades the external quantum efficiency (EQE) of blue InGaN µLEDs, resulting in EQE decreases with shrinking size. Second, panchromatic cathodoluminescence finds evidence that most of the carriers can be trapped before reaching the sidewall due to high
A
0
. This results in shortened diffusion length of carriers and reduces the number of carriers reaching the sidewall. Consequently, the opposite trend of increasing EQE with shrinking size occurs in the case of red InGaN µLEDs due to an ineffective
A
s
. Furthermore, an 8.3 nm quantum well of InGaN with 13% Indium content that can reach a ≈690 nm wavelength at the low current is shown.
•FeCrAl alloy was oxidized in pressurized 360°C water and 1200°C steam.•Compared to Zr alloy, FeCrAl alloy showed much lower weight change after oxidation.•FeCrAl alloy showed weight loss or gain ...depending on test conditions.•Fe2O3 was mainly formed on the surface of FeCrAl alloy after 360°C corrosion test.•Al2O3 was mainly formed on the surface of FeCrAl alloy after 1200°C oxidation test.
The oxidation behaviour of the FeCrAl alloy under normal operating conditions of a light water reactor is reported. In a comparative study, Zr-based and FeCrAl alloy samples were corroded in pressurized 360°C water for up to 500days or oxidized at 1200°C for 3000s in a steam environment. Compared to Zr-based alloys, the FeCrAl alloy showed extremely low weight change after both tests. The microstructure of the oxides formed on FeCrAl alloys was characterized by various analysing techniques. It was concluded that depending on the test conditions, mostly different oxide phases of α-Fe2O3 and α-Al2O3 were formed.
The aim of the present study was to analyze the long-term effects of transcranial direct current stimulation (tDCS) of the bilateral prefrontal cortex combined with computer-assisted cognitive ...training on working memory and cognitive function in healthy older adults aged at least 65 years. Forty healthy older adults were enrolled and randomly assigned to two groups: anodal and sham tDCS. All participants completed 10 sessions of computer-assisted cognitive training, combined with tDCS of the bilateral prefrontal cortex. The accuracy of the verbal working memory task and performance of the digit span forward test were significantly improved after computer-assisted cognitive training combined with bifrontal anodal tDCS as compared with that after computer-assisted cognitive training combined with sham tDCS. Moreover, the effect lasts for 4 weeks in the verbal working memory task. We suggest that the tDCS-induced changes in the bilateral prefrontal excitability during computer-assisted cognitive training may have beneficial effects on age-related cognitive decrement in healthy older adults.
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