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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]

Poly(styrene-sodium p-styrene sulfonate) microspheres with porous morphology were prepared by dispersion polymerization and seed swelling selecting two monomers of sodium p-styrene sulfonate and styrene, which are denoted as P(St-NaSS). The method is simple and easy to effectively control the pore structure microspheres. The SEM results showed that the surface morphology of P(St-NaSS) microspheres is in porous, and the diameter of pores is about 0.5 μm. In this paper, the influence of swelling time on the pore size was investigated. The SEM results indicated that the longer the swelling time, the larger the pore size of microspheres. The absorbing hybrids of swelled multi-porous P(St-NaSS) @MWCNTs and non-swelled P(St-NaSS)@MWCNTs with three-dimensional conductive network were assembled by π bond stacking effect, and study the strength of its absorption of electromagnetic waves. Compared with P(St-NaSS)@MWCNTs hybrids, the multi-porous P(St-NaSS) hybrids exhibited better absorbing performance, the reflection loss is -35.24 dB at 7.15 GHz at 2 mm thick, while the reflection loss of P(St-NaSS)@MWCNTs is -24.63 dB. The experimental results show that the existence of porous in wave-transparent microspheres played an important role in improving the impedance matching, increasing the path of multiple reflection scattering, which is beneficial to improve the absorption of MWCNTs. [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]

Interest in the development of grid-level energy storage systems has increased over the years. As one of the most popular energy storage technologies currently available, batteries offer a number of high-value opportunities due to their rapid responses, flexible installation, and excellent performances. However, because of the complexity, multifunctionality, and wide deployment of power grids, trade-offs in battery performance exist, especially when considering economics, environmental effects, and safety. Therefore, establishing a comprehensive assessment of battery technologies is an urgent undertaking. In this work, we present an analysis of rough sets to evaluate the integration of battery systems (e.g., lead–acid batteries, lithium-ion batteries, nickel/metal–hydrogen batteries, zinc–air batteries, and Na–S batteries) into a power grid. Specifically, technological properties, economic significance, environmental effects, and safety of these battery systems are evaluated on the basis of rough set theory. In addition, some perspectives are provided to promote the development of battery technologies for grid-level energy storage. [ABSTRACT FROM AUTHOR]

Inspired by the flexibility of the bottom-up approach in choosing building blocks of two-dimensional (2D) materials, a π-conjugated metal complex nanosheet (HHTP-Cu) was successfully prepared by the coordination of the ligand 2,3,6,7,10,11-hexahydroxytriphenylene (HHTP) and Cu(II) ion at the water/oil interface. Field-emission scanning electron microscopy disclosed the large-size domain and transmission electron microscopy revealed the sheet morphology of the nanosheet. The flat and smooth surface was also confirmed by atomic force microscopy which further demonstrated the proposed structure. Energy dispersive X-ray spectroscopy was applied to verify the homogeneous distribution of the elements while X-ray photoelectron spectroscopy was used to investigate the composition of the nanosheet. [ABSTRACT FROM AUTHOR]

Post-rift tectonic activities have been widely observed in the northern continental margin of the South China Sea, especially during the late Miocene. Large numbers of faults became active. Unconformities, uplift of faulted blocks, sequence tilting, erosion along the Dongsha massif and canyon incision were also discriminated at this stage in the Pearl River Mouth basin (PRMB) and the area to the east. This tectonism has been named Dongsha Event. A number of hypotheses have been put forward to explain the mechanism of the Dongsha Event, such as high-velocity lower crustal flow, magmatic underplating, and arc-continent collision. To investigate the tectonic dynamics, sequence contact relationships, fault activities, and magmatism were analyzed along large numbers of seismic profiles that cover the eastern PRMB and Southwest Taiwan Basin. The timing, affected regions, and differences in the intensity of tectonic deformation were assessed, upon which the plate bending model was favored. In order to check the reasonableness of plate bending model, effective elastic thickness and other geodynamic parameters were calculated constrained by uplift area width and regarding the trench as sediment filling. A maximum Te value of ~27 km and a minimum value of ~4 km were obtained. Integrating with the former stress field calculation, we conclude that the Dongsha Event was mainly affected by subduction and collision of the South China Sea toward the Philippine Sea plate. This event commenced at about 10 Ma and peaked at around 3.6 Ma. Although the high effective elastic thickness required is a problem to be addressed, this research provides by far the most comprehensive evidences to the mechanism of the Dongsha Event. [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]

Two novel conjugated donor-acceptor copolymers P1 and P2 based on acylbenzotrithiophene derivatives were prepared under Stille reaction conditions. Molecular weights of the polymers were determined by gel permeation chromatography. Thermal properties were studied by TGA and DSC methods, while optical and electrochemical properties were studied by UV spectroscopy and cyclic voltammetry. Effect of different fullerene derivatives PCBM and PCBM on photovoltaic characteristics was also studied. [ABSTRACT FROM AUTHOR]

A polymer blend comprising poly(3-hexylthiophene) (P3HT) donor and poly[2,7-(9,9′-octyl-fluorene)-alt-5,5-(4′,7′-di-2-thienyl-5′,6′-bis(hexyloxy)-2′,1′,3′-benzothiadiazole)] (PFDTBT-OC6) acceptor is used as the active layer to fabricate all-polymer solar cells. The blend morphology variance processed with pure and mixed solvents, and the related photovoltaic performance, are investigated in detail. It is found that, due to its low surface energy, a thin P3HT enrichment layer on the top surface of the active layer greatly increases bimolecular recombination and results in S-kinks of the illuminated current density-voltage curves. With the incorporation of p-xylene (a marginal solvent of P3HT) in the blend solution, the P3HT enrichment atop the active layer surface is effectively decreased because the high boiling-point p-xylene suppresses the diffusion of P3HT chains toward the top surface during the film-drying process. The bimolecular recombination was thus improved and the S-kinks of the photovoltaic curves were completely removed. The overall power conversion efficiencies of the devices are strongly boosted (from 0.88% to 1.41%) when chlorobenzene: p-xylene mixed solvent is used to replace pure chlorobenzene. [ABSTRACT FROM AUTHOR]

Donor-acceptor (D-A)-conjugated polymers P(BT-C1) and P(BT-C2), with dithieno[2,3- b;7,6- b]carbazole (C1) or dithieno[ 3,2- b;6,7- b]carbazole (C2) as D-unit and benzothiadiazole (BT) as A-unit, were synthesized. The optical bandgaps of the polymers are similar (1.84 and 1.88 eV, respectively). The structures of donor units noticeably influence the energy levels and backbone curvature of the polymers. P(BT-C1) shows a large backbone curvature; its highest occupied molecular orbital (HOMO) energy level is −5.18 eV, whereas P(BT-C2) displays a pseudo-straight backbone and has a HOMO energy level of −5.37 eV. The hole mobilities of the polymers without thermal annealing are 1.9×10 and 2.7×10 cmVs for P(BT-C1) and P(BT-C2), respectively, as measured by organic thin-film transistors (OTFTs). Polymer solar cells using P(BT-C1) and P(BT-C2) as the donor and phenyl-C-butyric acid methyl ester (PCBM) as the acceptor were fabricated. Power conversion efficiencies (PCEs) of 4.9% and 5.0% were achieved for P(BT-C1) and P(BT-C2), respectively. The devices based on P(BT-C2) exhibited a higher V due to the deeper HOMO level of the polymer, which led to a slightly higher PCE. [ABSTRACT FROM AUTHOR]

Studies investigating the association between glutathione S-transferase P1 ( GSTP1) gene polymorphism and bladder cancer (BC) risk have reported conflicting results. In order to clarify the effect of GSTP1 polymorphism on the BC susceptibility, we conducted an updated system review of published epidemiology studies to provide more precise evidence. We performed a systematic search of PubMed, EMBASE, and China National Knowledge Infrastructure (CNKI). 20 studies with 4,428 BC cases and 5,457 controls were identified. The combined analyses based on all studies showed that there was a significant difference in the genotype distribution in GSTP1(A313G) polymorphism between BC cases and controls not only in Asians (GG vs. AA + AG, OR = 1.59, 95 % CI = 1.01-2.51) but also in Caucasians (GG vs. AA + AG, OR = 1.51, 95 % CI = 1.11-2.06). Upon stratification for smoking status, we observed no statistically significant difference in genotype distribution of GSTP1 in ever-smokers. Combination of the high-risk genotypes ( GSTM1 null + GSTT1 null + GSTP1 313 A/G or G/G) demonstrated further increase in the BC risk (OR = 6.64, 95 %CI = 3.63-12.16). This meta-analysis suggests that GSTP1 313 G/G polymorphism is a strong predisposing risk factor for BC. [ABSTRACT FROM AUTHOR]

Conjugated polar polymers, in which the conjugated backbones are chemically anchored with functional polar side groups, can be processed with water/alcohol solvents, and thus multilayered device architectures can be easily realized via sequential solution processing of the toluene-soluble emissive polymer and alcohol-soluble electron-transporting polymer without intermixing. Regarding their use in organic optoelectronic devices, the success in achieving efficient charge injection and intimate contact between metal electrodes and organic semiconductors is very vital for enhancing the device performance. In this short review, it gives a brief review to neutral alcohol-soluble phosphonate-functionalized polyfluorene, mainly concerning the electronic structure at the phosphonate-functionalized polyfluorene/aluminum cathode interface and its successful application in multilayered polymer optoelectronic devices including polymer light-emitting diodes and polymer solar cells. [ABSTRACT FROM AUTHOR]

series of conjugated copolymers of 9,9-dioctylfluorene and symmetrical pyrazine unit (BY) were synthesized by Suzuki copolymerization and were used as novel light-emitting materials in PLEDs. Efficient energy transfer was observed in both thin film and solution. Compared with the lowest occupied molecular orbital (LUMO) energy level of the polyfluorenes homopolymer (PFO), the lower LUMO energy levels of copolymers indicated that the introduction of the BY unit would be benefit to electron injection. The turn-on voltages of their single-layer electroluminescent (EL) devices (ITO/PEDOT/polymer/LiF/Al) were at 6.1-4.0 V, which were much lower than that of PFO (7.0 V). The maximum brightness, current efficiency, and external quantum efficiency of all PFBY copolymers were higher than those of the PFO homopolymer. The single-layer device of PFBY5 was the best one in the copolymers, with a maximum brightness of 485 cd/m, a current efficiency of 0.29 cd/A, and an external quantum efficiency of 0.10%. The introduction of PVK and TPBI for the multilayer device of PFBY5 increased the device efficiencies, which showed a maximum brightness of 3012 cd/m, a maximum current efficiency of 1.81 cd/A, and an external quantum efficiency of 0.66%. [ABSTRACT FROM AUTHOR]

A new kind of single-quantum-well electroluminescent (EL) device consists of a hole transport N,N-Bis(3-methyphenyl)-N,N-diphenylbenzidine(TPD) layer, and electron transport 8-(quinolinolate)-aluminum(Alq) layer and a light emitting layer of Alq doped with 5,6,11,12-tetraphenylnaphthacene (rubrene) has been fabricated by the multisource-type high-vaccum organic molecular deposition. The dopant rubrene is as a potential well, and the undoped Alq layer is as a barrier layer. The EL spectra shows the spectral narrowing and the emission peak energy blue-shift, and the efficiency and luminance of the device have been significantly improved. The experimental phenomena is explained as the result of recombination of carriers from the quantized energy state. [ABSTRACT FROM AUTHOR]

Remarkable improvement in efficiency and electroluminescence (EL) has been observed in an organic EL device, which consists of a hole-transport layer and a luminescent layer. The hole-transport layer is an N,N′-bis(3-methyphenyl)-N,N′-diphenylbenzidine film. The doped emitting layer consists of 8-(quinolinolate)-aluminum as the host and rubrene as the emission dopant. The doped cell with aluminum cathode demonstrated a luminance in excess of 20,000 cd/m2 and an external quantum efficiency of 2.7%, which is about four times and three times, respectively, greater than those of the undoped cell. The EL emission from the device shows spectral narrowing and a shift to higher energy. [ABSTRACT FROM AUTHOR]

Several organic electroluminescent devices have been fabricated by multi-source high vacuum deposition system. For high brightness organic electroluminescent device, the maximum brightness is over 40000 cd/m2. For quantum well structures, quantum size effect has been investigated and the high light emission efficiencies of the devices have been obtained. White-light emission from organic multi-quantum well structures is proposed at first. Brightness of the white-light MQW devices reaches 4000 cd/m2 at 17 V. [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]