The development of high-performance near-infrared organic light-emitting diodes is hindered by strong non-radiative processes as governed by the energy gap law. Here, we show that exciton ...delocalization, which serves to decouple the exciton band from highly vibrational ladders in the S0 ground state, can bring substantial enhancements in the photoluminescence quantum yield of emitters, bypassing the energy gap law. Experimental proof is provided by the design and synthesis of a series of new Pt(ii) complexes with a delocalization length of 5–9 molecules that emit at 866–960 nm with a photoluminescence quantum yield of 5–12% in solid films. The corresponding near-infrared organic light-emitting diodes emit light with a 930 nm peak wavelength and a high external quantum efficiency up to 2.14% and a radiance of 41.6 W sr−1 m−2. Both theoretical and experimental results confirm the exciton–vibration decoupling strategy, which should be broadly applicable to other well-aligned molecular solids.Pt(ii) complexes allow the fabrication of efficient near-infrared organic light-emitting diodes that operate beyond the 900 nm region.
A unique “clean‐lifting transfer” (CLT) technique that applies a controllable electrostatic force to transfer large‐area and high‐quality CVD‐grown graphene onto various rigid or flexible substrates ...is reported. The CLT technique without using any organic support or adhesives can produce residual‐free graphene films with large‐area processability, and has great potential for future industrial production of graphene‐based electronics or optoelectronics.
Among different printing techniques, direct ink writing is commonly used to fabricate 3D battery and supercapacitor electrodes. The major advantages of using the direct ink writing include ...effectively building 3D structure for energy storage devices and providing higher power density and higher energy density than traditional techniques due to the increased surface area of electrode. Nevertheless, direct ink writing has high standards for the printing inks, which requires high viscosity, high yield stress under shear and compression, and well-controlled viscoelasticity. Recently, a number of 3D-printed energy storage devices have been reported, and it is very important to understand the printing process and the ink preparation process for further material design and technology development. We discussed current progress of direct ink writing technologies by using various electrode materials including carbon nanotube-based material, graphene-based material, LTO (Li4Ti5O12), LFP (LiFePO4), LiMn1-xFexPO4, and Zn-based metallic oxide. Based on achieve electrochemical performance, these 3D-printed devices deliver performance comparable to the energy storage device fabricated using traditional methods still leaving large room for further improvement. Finally, perspectives are provided on the potential future direction of 3D printing for all solid-state electrochemical energy storage devices.
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•The 2D and 3D structures of energy storage devices are reviewed.•Energy storage devices are printed using different materials by 3D direct writing.•The 3D devices deliver a better performance than traditional fabrication methods.
The CoP nanoparticle catalyst had excellent catalytic activity and a short catalytic induction period in the presence of anions, and high sustainability in ammonia borane hydrolysis, with an initial ...turnover frequency of 72.2 mol
mol
min
at ambient temperature. This value is unprecedented for noble-metal-free catalytic systems.
Anthropogenic activities accompanied by heavy metal waste threaten the environment. Heavy metal pollution alters the soil microbial community composition, and the microorganisms that adapt to this ...stress increase in abundance. The remediation process of contaminated soil not only reduces the concentration of heavy metals but also alters the bacterial communities. High-throughput 16S rDNA sequencing techniques were applied to understand the changes in soil microbial communities. Using the remediation approach of the soil mixing, the concentrations of heavy metals in the contaminated areas were diluted and the soil environment was changed. The change of soil environment as a disturbance contributed to the alteration of microbial diversity of the remediated areas. The pH and heavy metals (Cr, Cu, Ni, and Zn) were the most influential factors driving the changes in community structure. The bacterial community structure was significantly different among sample areas. The decrease of heavy metals in soil may be the important factors that changed the microbial composition. This study provides the better understanding of the changes in composition of microbial communities affected by the remediation process in heavy metal-contaminated soil.
Horizontal-axis wind turbines (HAWTs) are the primary devices used in the wind energy sector. Systems used to evaluate the design of turbine blades and generators are key to improve the performance ...of HAWTs. Analysis of aerodynamic performance in turbine blades focuses on wind speed, rotational speed, and tip speed ratios (TSRs). This paper reviews computational as well as experimental methods used to measure the aerodynamic performance of HAWT blades. Among the numerical methods, we examine classical blade element momentum (BEM) theory and the modified BEM as well as computational fluid dynamics (CFD) and the BEM-CFD mixed approach. We also discuss the current computational methods for investigating turbine wake flows. Among the experimental methods, we examine field testing and wind tunnel experiment including aerodynamic torque measurement and blockage effects. A comparison of numerical and experimental approaches can help to improve accuracy in the prediction of wind turbine performance and facilitate the design of HAWT blades.
Recently, the long non-coding RNA (lncRNA) H19 has been identified as an oncogenic gene in multiple cancer types and elevated expression of H19 was tightly linked to tumorigenesis and cancer ...progression. However, the molecular basis for this observation has not been characterized in colorectal cancer (CRC) especially during epithelial to mesenchymal transition (EMT) progression. In our studies, H19 was characterized as a novel regulator of EMT in CRC. We found that H19 was highly expressed in mesenchymal-like cancer cells and primary CRC tissues. Stable expression of H19 significantly promotes EMT progression and accelerates in vivo and in vitro tumor growth. Furthermore, by using bioinformatics study and RNA immunoprecipitation combined with luciferase reporter assays, we demonstrated that H19 functioned as a competing endogenous RNA (ceRNA) for miR-138 and miR-200a, antagonized their functions and led to the de-repression of their endogenous targets Vimentin, ZEB1, and ZEB2, all of which were core marker genes for mesenchymal cells. Taken together, these observations imply that the lncRNA H19 modulated the expression of multiple genes involved in EMT by acting as a competing endogenous RNA, which may build up the missing link between the regulatory miRNA network and EMT progression.
Asymmetrical cell division (ACD) maintains the proper number of stem cells to ensure self-renewal. In cancer cells, the deregulation of ACD disrupts the homeostasis of the stem cell pool and promotes ...tumour growth. However, this mechanism is unclear. Here, we show a reduction of ACD in spheroid-derived colorectal cancer stem cells (CRCSCs) compared with differentiated cancer cells. The epithelial-mesenchymal transition (EMT) inducer Snail is responsible for the ACD-to-symmetrical cell division (SCD) switch in CRCSCs. Mechanistically, Snail induces the expression of microRNA-146a (miR-146a) through the β-catenin-TCF4 complex. miR-146a targets Numb to stabilize β-catenin, which forms a feedback circuit to maintain Wnt activity and directs SCD. Interference with the Snail-miR-146a–β-catenin loop by inhibiting the MEK or Wnt activity reduces the symmetrical division of CRCSCs and attenuates tumorigenicity. In colorectal cancer patients, the Snail(High)Numb(Low) profile is correlated with cetuximab resistance and a poorer prognosis. This study elucidates a unique mechanism of EMT-induced CRCSC expansion.
Abstract
We propose a systematic methodology to identify the topological phase transition through a self-supervised machine learning model, which is trained to correlate system parameters to the ...non-local observables in time-of-flight experiments of ultracold atoms. Different from the conventional supervised learning approach, where the predicted phase transition point is very sensitive to the training region and data labeling, our self-supervised learning approach identifies the phase transition point by the largest deviation of the predicted results from the known system parameters and by the highest confidence through a systematic shift of the training regions. We demonstrate the robust application of this approach results in various 1D and 2D exactly solvable models, using different input features (time-of-flight images, spatial correlation function or density–density correlation function). As a result, our self-supervised approach should be a very general and reliable method for many condensed matter or solid state systems to observe new states of matters solely based on experimental measurements, even without
a priori
knowledge of the phase transition models.
Oncogene-induced senescence causes hepatocytes to secrete cytokines, which induce their immune-mediated clearance to prevent tumor initiation, a process termed “senescence surveillance.” However, ...senescent hepatocytes give rise to hepatocellular carcinomas (HCCs), if the senescence program is bypassed or if senescent cells are not cleared. Here, we show context-specific roles for CCR2+ myeloid cells in liver cancer. Senescence surveillance requires the recruitment and maturation of CCR2+ myeloid cells, and CCR2 ablation caused outgrowth of HCC. In contrast, HCC cells block the maturation of recruited myeloid precursors, which, through NK cell inhibition, promote growth of murine HCC and worsen the prognosis and survival of human HCC patients. Thus, while senescent hepatocyte-secreted chemokines suppress liver cancer initiation, they may accelerate the growth of fully established HCC.
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•The CCL2-CCR2 axis is necessary for clearance of pre-cancerous senescent hepatocytes•Absence of the CCL2-CCR2 axis leads to HCC outgrowth from senescent hepatocytes•Peritumoral tissue senescence accelerates growth of HCC in mice and humans•Senescence-recruited CCR2+ myeloid cells enhance HCC growth by NK cell inhibition
Eggert et al. show that CCL2 is secreted from oncogene-induced senescent hepatocytes to recruit CCR2+ immature myeloid cells (iMC). These iMC differentiate into macrophages that clear pre-malignant senescent cells, but iMC promote growth of established hepatocellular carcinoma through NK cell inhibition.
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