We present the results of a thorough study of wet chemical methods for transferring chemical vapor deposition grown graphene from the metal growth substrate to a device-compatible substrate. On the basis of these results, we have developed a "modified RCA clean" transfer method that has much better control of both contamination and crack formation and does not degrade the quality of the transferred graphene. Using this transfer method, high device yields, up to 97%, with a narrow device performance metrics distribution were achieved. This demonstration addresses an important step toward large-scale graphene-based electronic device applications.

We report comprehensive characterization of electrolyte-gated polymer thin-film transistors (TFTs) incorporating solution processable polymer semiconductors and high capacitance "ion gel" gate dielectrics. The ion gel dielectrics comprise self-assembled networks of triblock copolymers such as poly(styrene-b-methylmethacrylateb-styrene) [PS-PMMA-PS] that are swollen with ionic liquids, e.g., (1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([EMIM][TFSI]). The capacitance of the gels is exceptionally large (>10 µF/cm 2 at 10 Hz), which is derived from the high concentration of mobile ions and facilitates operation of ion gelgated organic TFTs (GEL-OTFTs) at very low voltages (< 2.5 V). Gate-induced hole densities in GEL-OTFTs employing different polythiophene semiconductors in the channel are on the order of 10 14 carriers/ cm 2 , with associated saturation hole mobilities that are also remarkably large, ∼1 cm 2 /(V s), likely because of the large gate-induced carrier densities. Examination of the frequency response of GEL-OTFTs indicates that increases in the OFF current with frequency ultimately limit switching speed; the cutoff frequency correlates with the ionic conductivity versus frequency response of the gel dielectric. Further, attenuated total internal reflection infrared (ATR-IR) spectroscopy of the ion gel/polymer semiconductor gate stack reveals that the conductance switching mechanism in GEL-OTFTs spans both electrochemical and electrostatic (field effect) regimes. Specifically, modeling of the time dependence of the near-infrared polaron absorption in gated GEL-OTFTs indicates that the [TFSI]anion diffusivity in regioregular poly(3-hexylthiophene) is on the order of 10 -12 cm 2 /s at room temperature. This diffusivity implies that, for time scales greater than 1 ms, there is significant penetration (>1 nm) of [TFSI]anion into the polymer semiconductor at the gel/polymer semiconductor interface, corresponding to an electrochemical doping process. On the other hand, for time scales shorter than 1 ms (i.e., for GEL-OTFT switching frequencies >1 kHz), the device switching mechanism can be viewed as primarily electrostatic as average ion penetration depths are less than 1 nm.

The rapid generation of various species and strains of laboratory animals using CRISPR/Cas9 technology has dramatically accelerated the interrogation of gene function in vivo. So far, the dominant approach for genotyping of genome-modified animals has been the T7E1 endonuclease cleavage assay. Here, we present a polyacrylamide gel electrophoresis-based (PAGE) method to genotype mice harboring different types of indel mutations. We developed 6 strains of genome-modified mice using CRISPR/Cas9 system, and utilized this approach to genotype mice from F0 to F2 generation, which included single and multiplexed genome-modified mice. We also determined the maximal detection sensitivity for detecting mosaic DNA using PAGE-based assay as 0.5%. We further applied PAGE-based genotyping approach to detect CRISPR/Cas9-mediated on- and off-target effect in human 293T and induced pluripotent stem cells (iPSCs). Thus, PAGE-based genotyping approach meets the rapidly increasing demand for genotyping of the fast-growing number of genome-modified animals and human cell lines created using CRISPR/Cas9 system or other nuclease systems such as TALEN or ZFN.

Innate lymphoid cells (ILCs) communicate with other hematopoietic and nonhematopoietic cells to regulate immunity, inflammation and tissue homeostasis. How ILC lineages develop and are maintained remains largely unknown. In this study we observed that a divergent long noncoding RNA (lncRNA), lncKdm2b, was expressed at high levels in intestinal group 3 ILCs (ILC3s). LncKdm2b deficiency in the hematopoietic system led to reductions in the number and effector functions of ILC3s. LncKdm2b expression sustained the maintenance of ILC3s by promoting their proliferation through activation of the transcription factor Zfp292. Mechanistically, lncKdm2b recruited the chromatin organizer Satb1 and the nuclear remodeling factor (NURF) complex onto the Zfp292 promoter to initiate its transcription. Deletion of Zfp292 or Bptf also abrogated the maintenance of ILC3s, leading to susceptibility to bacterial infection. Therefore, our findings reveal that lncRNAs may represent an additional layer of regulation of ILC development and function.

Cyclic GMP-AMP synthase (cGAS) senses cytosolic DNA during viral infection and catalyzes synthesis of the dinucleotide cGAMP, which activates the adaptor STING to initiate antiviral responses. Here we found that deficiency in the carboxypeptidase CCP5 or CCP6 led to susceptibility to DNA viruses. CCP5 and CCP6 were required for activation of the transcription factor IRF3 and interferons. Polyglutamylation of cGAS by the enzyme TTLL6 impeded its DNA-binding ability, whereas TTLL4-mediated monoglutamylation of cGAS blocked its synthase activity. Conversely, CCP6 removed the polyglutamylation of cGAS, whereas CCP5 hydrolyzed the monoglutamylation of cGAS, which together led to the activation of cGAS. Therefore, glutamylation and deglutamylation of cGAS tightly modulate immune responses to infection with DNA viruses.

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Innate lymphoid cells (ILCs) reside in mucosal surfaces to potentiate immune responses, sustain mucosal integrity and maintain tissue homeostasis. However, how tumor infiltrating ILCs modulate tumor development and progression is unclear. Here we profiled tumor infiltrating ILCs during colorectal cancer (CRC) progression by single-cell RNA sequencing. We identified six clusters of tumor infiltrating ILCs with unique features. ILC1s expressed inhibitory receptors and underwent inhibitory functional conversion at the late stage of CRC. ILC2s were classified into three subsets (called ILC2-A,-B,-C), of which ILC2-C subset could facilitate tumor progression. HS3ST1 and PD1 were highly expressed in ILC2s of late stage CRC tumors and deficiency of HS3ST1 or PD1 in ILC2s suppressed tumor growth. Moreover, ILC3s transdifferentiated into ILCregs during CRC progression and ILCregs promoted tumor growth. Of note, TGF-β signaling initiated the conversion of ILC3s to ILCregs and blockade of TGF-β signaling could disrupt the ILCreg transdifferentiation and inhibited tumor growth. Thus, intervention of ILC conversions might be a potential strategy for CRC immunotherapy.

With the arrival of the Internet of Things (IoTs) era, there is a growing requirement for systems with many sensor nodes in a variety of fields of applications. The demands for wireless, sustainable and independent operation are becoming more and more important for large‐scale sensor networks and systems. For these purposes, a self‐powered sensory system that can utilize the self‐harvested energy from its surroundings to drive the sensors and directly sense external stimuli has attracted great attention. The invention and rapid development of piezoelectric generators (PENGs), which take Maxwell's displacement current as the driving force, has been pushing forward research on self‐powered active mechanical sensors, electronic skins, and human‐robotic interaction. Here, this review starts with a brief introduction of piezoelectric materials, fabrication, and performance improvement. Then, the energy harvesters used for self‐power systems based on recent progress are reviewed. After that, PENGs applications toward recent self‐powered active sensors are divided into four aspects and highlighted, respectively. Moreover, some challenges and future directions for the self‐powered multifunctional sensors are put forward. It is believed that through the continuous investigations into PENG‐based self‐powered active sensors, they will soon be used in touch screens, electronic skins, health care, environmental monitoring, and intelligence systems.