Transposable elements (TEs) make up a majority of a typical eukaryote's genome, and contribute to cell heterogeneity in unclear ways. Single-cell sequencing technologies are powerful tools to explore ...cells, however analysis is typically gene-centric and TE expression has not been addressed. Here, we develop a single-cell TE processing pipeline, scTE, and report the expression of TEs in single cells in a range of biological contexts. Specific TE types are expressed in subpopulations of embryonic stem cells and are dynamically regulated during pluripotency reprogramming, differentiation, and embryogenesis. Unexpectedly, TEs are expressed in somatic cells, including human disease-specific TEs that are undetectable in bulk analyses. Finally, we apply scTE to single-cell ATAC-seq data, and demonstrate that scTE can discriminate cell type using chromatin accessibly of TEs alone. Overall, our results classify the dynamic patterns of TEs in single cells and their contributions to cell heterogeneity.
Silicon boron carbon nitride ceramic nanocomposites filled with nitrogen sulfur dual-doped graphene sheets (SiBCN/NSGs) were designed and synthesized by inserting pyrolyzed NSGs into the polymer ...derived SiBCN via ball ball milling technique and their feasibility to serve as lithium ion battery anode was tested. The insertion of NSGs in SiBCN caused extrinsic defects and more active sites, both increased the lithiation and anode stability. The resulting material significantly improved the Li-ion loading capacity and gave a higher rate ability. The high cycling performances were attributed to the stacked graphene sheets of NSGs and increased disordered carbon sites (amorphous structure), such as rearrangement of -sp2 carbon chains and formation of B(C)N domains of polymer derived ceramic (PDC). The NSGs generated extrinsic defects and more active sites, hence promoted the electrode performance. The nanocomposites exhibited a reversible capacity of 785 mAh g−1 even at a high current density of 450 mA g−1 over 800 cycles, representing a high retained capacity of ∼780 mAh g−1 with an average decay of 0.006% per cycle. Furthermore, the SiBCN anode revealed a charge capacity of 365 mAh g−1 at 450 mA g−1 after 500 cycles, indicating that both the assembled anodes have potential practical applications in lithium-ion batteries.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
4.
Poly(ionic liquid) composites Zhang, Su-Yun; Zhuang, Qiang; Zhang, Miao ...
Chemical Society reviews,
03/2020, Volume:
49, Issue:
6
Journal Article
Peer reviewed
Open access
Poly(ionic liquid)s (PILs), as an innovative class of polyelectrolytes, are composed of polymeric backbones with IL species in each repeating unit. The combined merits of the polymers and ILs make ...them promising materials for composites in materials science. Particularly, the integration of PILs with functional substances (PIL composites) opens up a new dimension in utilizing ionic polymers by offering novel properties and improved functions, which impacts multiple subfields of our chemical society. This review summarizes recent developments of PIL composites with a special emphasis on the preparation techniques that are based on the intrinsic properties of the PILs and the synergistic effects between the PILs and substances of interest for diverse applications.
This review highlights recent advances in the development of poly(ionic liquid)-based composites for diverse materials applications.
In this paper, we presented a new strategy for fabrication of polymeric composites combined with low dielectric loss and desirable thermal conductivity. With the incorporation of hyperbranched ...polyborosilazane (hb-PBSZ) into bisphenol A cyanate ester (BADCy) matrix, the modified hb-PBSZ/BADCy resin with 4 wt% hb-PBSZ possessed a low dielectric constant (å) value of 2.37 and relatively low dielectric loss tangent value of 0.008 at 1MHz. Furthermore, by integrating micrometer boron nitride particles (mBN) into hb-PBSZ/BADCy matrix, the mBN/hb-PBSZ/BADCy composites presented relatively low å of 3.09, desirable thermally conductive coefficient (λ of 0.63 W/(m·K)) and thermal diffusivity (α of 0.42 mm2/s) values. It provides an important perspective for designing dielectric and thermally conductive polymeric composites for electrical packaging and energy storage fields.
Pancharatnam-Berry (PB) metasurfaces have intrigued a great deal of interest in recent years for anomalous reflection/refraction, vortex plate, orbital angular momentum, flat lens, photonic spin hall ...effect (PSHE), holograms and reflect/transmit arrays. However, almost all designs are restricted to fixed electrical performance/functionality once the design is finished. Here, we report for the first time a strategy for PB metasurface with agile working frequency by involving each meta-atom with tunable PIN diodes. For verification, a tunable PB metasurface with frequency reconfigurability is designed and numerically characterized across C and X band. By controlling the external voltages imposed on the diodes, numerical results show that the operation band with 180° phase difference between orthogonal reflection coefficients can be dynamically controlled. As such, the resulting PB metasurface composed of these orderly rotated meta-atoms exhibits a broadband PSHE with nearly 100% conversion efficiency in the "On" state while switches to dual well-separated bands in the "Off" state. Our proposal, not confined to PHSE, set a solid platform for PB phase control and can be populated to any dual-functional and/or multifunctional devices with high integrity, stability and low cost.
A novel triple-layer dual-mode meta-atom wherein an H-shaped structure is combined with a pair of symmetric patches is proposed. The composite structure substantially lowered the operation frequency, ...and balanced phase agility with transmission magnitude bandwidth. The transmission phase limit of the proposed composite structure approaches the theoretical limit. Because this structure has appealing features, we employed a set of these ultrathin meta-atoms to implement the phase distribution of an optimized array using the alternating projection method. An X-band single-feed quad-beam transmitarray consisting of 25×25 elements, each carefully designed to exhibit the desired transmission phase, was designed, simulated, physically implemented, and measured. Feeding the meta-array using a horn at its focus, four-beam radiation patterns with satisfactory sidelobe levels and gain were numerically and experimentally demonstrated. The peak gain was found to be 18.8 dB at 9.6 GHz, and the aperture efficiency was calculated as 38.3%. Moreover, the half-power beamwidth of the array antenna was approximately 7°, which was 50° narrower than that of a bare feed horn. Moreover, the gain of each beam was higher than 17 dB in all studied cases, which was at least 7 dB higher than that of a bare feed horn.
The ability to grow properly sized and good quality crystals is one of the cornerstones of single-crystal diffraction, is advantageous in many industrial-scale chemical processes
, and is important ...for obtaining institutional approvals of new drugs for which high-quality crystallographic data are required
. Typically, single crystals suitable for such processes and analyses are grown for hours to days during which any mechanical disturbances-believed to be detrimental to the process-are carefully avoided. In particular, stirring and shear flows are known to cause secondary nucleation, which decreases the final size of the crystals (though shear can also increase their quantity
). Here we demonstrate that in the presence of polymers (preferably, polyionic liquids), crystals of various types grow in common solvents, at constant temperature, much bigger and much faster when stirred, rather than kept still. This conclusion is based on the study of approximately 20 diverse organic molecules, inorganic salts, metal-organic complexes, and even some proteins. On typical timescales of a few to tens of minutes, these molecules grow into regularly faceted crystals that are always larger (with longest linear dimension about 16 times larger) than those obtained in control experiments of the same duration but without stirring or without polymers. We attribute this enhancement to two synergistic effects. First, under shear, the polymers and their aggregates disentangle, compete for solvent molecules and thus effectively 'salt out' (that is, induce precipitation by decreasing solubility of) the crystallizing species. Second, the local shear rate is dependent on particle size, ultimately promoting the growth of larger crystals (but not via surface-energy effects as in classical Ostwald ripening). This closed-system, constant-temperature crystallization driven by shear could be a valuable addition to the repertoire of crystal growth techniques, enabling accelerated growth of crystals required by the materials and pharmaceutical industries.
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FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We describe the application of S−H bond insertion reactions of aryl diazoacetates with cysteine residues that enabled metal‐free, S−H functionalization under visible‐light conditions. Moreover, this ...process could be intensified by a continuous‐flow photomicroreactor on the acceleration of the reaction (6.5 min residence time). The batch and flow protocols described were applied to obtain a wide range of functionalized cysteine derivatives and cysteine‐containing dipeptides, thus providing a straightforward and general platform for their functionalizations in mild conditions.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
A new 2-D ultra-thin transmissive phase gradient metasurface (TPGM) with polarization-independent property is proposed based on the generalized Snell's law of refraction. The super unit cell of the ...tri-layer TPGM consists of 6 \times 6 suitably selected elements with - {60}^\circ phase gradient at x -direction and 60° phase gradient at y -direction, respectively. The characterizations and working mechanisms of the TPGM are investigated in depth through theoretical calculation, comparative analysis, and electromagnetic (EM) simulation. Four types of TPGMs with different functionalities are proposed based on the derived four-step design method. Numerical results show that the TPGMs are capable of manipulating the differently polarized wave independently. For demonstration and potential applications, an ultra-thin polarization beam splitter (PBS) working at X-band is implemented by a specially designed 2-D TPGM and is launched by a wideband horn antenna from the perspective of high integration, simple structure, and low cost. Numerical and experimental results coincide well, indicating that the PBS advances in many aspects such as separating and controlling the orthogonally polarized waves with a polarized splitting ratio better than 18 dB, obtaining a comparable bandwidth of more than 600 MHz, gaining a high transmission efficiency and also adopting a simple fabrication process based on the convenient print circuit board (PCB) technology.