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The interplay between histone modifications and DNA methylation drives the establishment and maintenance of the cellular epigenomic landscape, but it remains challenging to investigate the complex relationship between these epigenetic marks across the genome. Here we describe a nanopore-sequencing-based-method, nanoHiMe-seq, for interrogating the genome-wide localization of histone modifications and DNA methylation from single DNA molecules. nanoHiMe-seq leverages a nonspecific methyltransferase to exogenously label adenine bases proximal to antibody-targeted modified nucleosomes in situ. The labelled adenines and the endogenous methylated CpG sites are simultaneously detected on individual nanopore reads using a hidden Markov model, which is implemented in the nanoHiMe software package. We demonstrate the utility, robustness and sensitivity of nanoHiMe-seq by jointly profiling DNA methylation and histone modifications at low coverage depths, concurrently determining phased patterns of DNA methylation and histone modifications, and probing the intrinsic connectivity between these epigenetic marks across the genome. The interplay between histone modifications and DNA methylation plays a crucial role in establishing and maintaining the epigenomic landscape. Here, the authors develop a nanopore sequencing based method for mapping histone modifications and DNA methylation from native, long, single DNA molecules. [ABSTRACT FROM AUTHOR]

The fourth paradigm of science has achieved great success in material discovery and it highlights the sharing and interoperability of data. However, most material data are scattered among various research institutions, and a big data transmission will consume significant bandwidth and tremendous time. At the meanwhile, some data owners prefer to protect the data and keep their initiative in the cooperation. This dilemma gradually leads to the "data island" problem, especially in material science. To attack the problem and make full use of the material data, we propose a new strategy of neural network training based on multi-source databases. In the whole training process, only model parameters are exchanged and no any external access or connection to the local databases. We demonstrate its validity by training a model characterizing material structure and its corresponding formation energy, based on two and four local databases, respectively. The results show that the obtained model accuracy trained by this method is almost the same to that obtained from a single database combining all the local ones. Moreover, different communication frequencies between the client and server are also studied to improve the model training efficiency, and an optimal frequency is recommended. [ABSTRACT FROM AUTHOR]

Metal–organic frameworks (MOFs), a new type of porous functional material, have attracted widespread attention in the field of adsorption separation, medicine, and catalysis, etc., due to their unique adjustable pore structure and large specific surface. The defective zirconium-based MOF is rich in terminal Zr–OH induced by the lack of linkers and the μ3-OH originating from the Zr cluster, exhibiting high affinity for the carboxyl and sulfonic acid groups in the dyes. We report the performance of two defective zirconium-based MOFs (MOF-808 and MIL-140C) to remove Eosin y (EY), Methyl orange (MO), and Orange g from the water. Owing to the strong affinity, larger specific surface area, and better-matched pore structure, MOF-808 exhibits higher adsorption capacity for EY and MO, with maximum adsorption capacities of 661.7 mg g−1 and 532.4 mg g−1, respectively. The adsorption kinetics, thermodynamics, adsorption cycle performance, and adsorption mechanism of two MOFs for three dyes were investigated. Adsorption thermodynamics and XPS analysis certified that both chemical adsorption and physical adsorption occur during the adsorption process, especially chemical adsorption. Desorption and regeneration tests demonstrate that both MOF-808 and MIL-140C maintained their high adsorption capacity after four cycles, indicating two MOFs are favorable candidates for removing pollutants. In this article, the adsorption performance of MOF-808 and MIL-140C on three different sizes and structures of anionic dyes is mainly studied. The results show that MOF-808 has better adsorption performance for EY and MO. At the same time, the adsorption results show that the chemical adsorption between the adsorbate and the MOFs material plays a leading role in the adsorption, resulting in a high adsorption capacity for EY, although the EY molecule has a larger molecular size. [ABSTRACT FROM AUTHOR]

An attempt was made to analyze the damage evolution and ductile fracture of incremental forming at the microscopic level. Firstly, an extended Gurson-Tvergaard-Needleman (GTN) model integrating with Hill'48 anisotropic yield criterion was established and numerically implemented by User-defined Material Subroutine (VUMAT) in the commercial finite element software ABAQUS. Then, the VUMAT program was verified via a single element test, and its damage parameters were determined through the combination of the simulation and the experiment of a tensile test. Afterwards, based on the extended GTN model, a finite element model of incremental forming was established and experimentally verified. And the influence of different values of two damage parameters, the volume fraction of void nucleating particles f and the mean plastic strain value when voids nucleate ε, on the damage evolution of incremental forming was explored. It shows that there is almost no connection between the microscopic equivalent strain $$ {\overline{\varepsilon}}_{\mathrm{m}}^{\mathrm{pl}} $$ and the values of f and ε. However, the maximum value of void volume fraction will increase significantly with the increase of f or with the decrease of ε. Finally, void volume fraction was proved to be an effective index to predict crack occurrence of incremental forming. [ABSTRACT FROM AUTHOR]

To realize power efficient solution-processed phosphorescent organic light-emitting diodes (s-PhOLEDs), the corresponding high driving voltage issue should be well solved. To solve it, efforts have been devoted to the exploitation of novel host or interfacial materials. However, the issues of charge trapping of phosphor and/or charge injection barrier are still serious, largely restraining the power efficiency (PE) levels. Herein, with the utilization of an exciplex-forming couple 4, 4′, 4″ -tris[3-methylphenyl(phenyl)amino]triphenylamine (m-MTDATA) and 1,3,5-tri(m-pyrid-3-yl-phenyl)benzene (TmPyPB), the efficient charge injection and transporting, barrier-free hole-electron recombination for the formation of the interfacial exciplex, and elimination of charge traps of phosphors in the emissive layer are realized simultaneously, resulting in a turn-on voltage of 2.36 V, a record high PE of 97.2 lm W−1, as well as extremely low driving voltage of 2.60 V at 100 cd m−2, 3.03 V at 1000 cd m−2 and 4.08 V at 10000 cd m−2. This report is the first time that the PE performance of s-PhOLED approaches 100 lm W−1 high level, even superior to the corresponding state-of-the-art performance of the same color vacuum-deposited PhOLED (v-PhOLED) counterpart. We anticipate this report opens a new avenue for achieving power efficient monochromatic and white s-PhOLEDs with simple structures. [ABSTRACT FROM AUTHOR]