Field-induced ionic motions in all-inorganic CsPbBr3 perovskite quantum dots (QDs) strongly dictate not only their electro-optical characteristics but also the ultimate optoelectronic device performance. Here, we show that the functionality of a single Ag/CsPbBr3/ITO device can be actively switched on a sub-millisecond scale from a resistive random-access memory (RRAM) to a light-emitting electrochemical cell (LEC), or vice versa, by simply modulating its bias polarity. We then realize for the first time a fast, all-perovskite light-emitting memory (LEM) operating at 5 kHz by pairing such two identical devices in series, in which one functions as an RRAM to electrically read the encoded data while the other simultaneously as an LEC for a parallel, non-contact optical reading. We further show that the digital status of the LEM can be perceived in real time from its emission color. Our work opens up a completely new horizon for more advanced all-inorganic perovskite optoelectronic technologies.

In this paper, we demonstrate microwave flexible thin-film transistors (TFTs) on biodegradable substrates towards potential green portable devices. The combination of cellulose nanofibrillated fiber (CNF) substrate, which is a biobased and biodegradable platform, with transferrable single crystalline Si nanomembrane (Si NM), enables the realization of truly biodegradable, flexible, and high performance devices. Double-gate flexible Si NM TFTs built on a CNF substrate have shown an electron mobility of 160 cm2/V·s and fT and fmax of 4.9 GHz and 10.6 GHz, respectively. This demonstration proves the microwave frequency capability and, considering today's wide spread use of wireless devices, thus indicates the much wider utility of CNF substrates than that has been demonstrated before. The demonstration may also pave the way toward portable green devices that would generate less persistent waste and save more valuable resources.

Inflammasome is an intracellular protein complex that serves as cytosolic pattern recognition receptor (PRR) to engage with pathogens and to process cytokines of the interleukin-1 (IL-1) family into bioactive molecules. It has been established that interleukin-1β (IL-1β) is important to host defense against Histoplasma capsulatum infection. However, the detailed mechanism of how H. capsulatum induces inflammasome activation leading to IL-1β production has not been studied. Here, we showed in dendritic cells (DCs) that H. capsulatum triggers caspase-1 activation and IL-1β production through NLRP3 inflammasome. By reciprocal blocking of Dectin-1 or Dectin-2 in single receptor-deficient DCs and cells from Clec4n-/-, Clec7a-/-, and Clec7a-/-Clec4n-/- mice, we discovered that while Dectin-2 operates as a primary receptor, Dectin-1 serves as a secondary one for NLRP3 inflammasome. In addition, both receptors trigger Syk-JNK signal pathway to activate signal 1 (pro-IL-1β synthesis) and signal 2 (activation of caspase-1). Results of pulmonary infection with H. capsulatum showed that CD103+ DCs are one of the major producers of IL-1β and Dectin-2 and Dectin-1 double deficiency abolishes their IL-1β response to the fungus. While K+ efflux and cathepsin B (but not ROS) function as signal 2, viable but not heat-killed H. capsulatum triggers profound lysosomal rupture leading to cathepsin B release. Interestingly, cathepsin B release is regulated by ERK/JNK downstream of Dectin-2 and Dectin-1. Our study demonstrates for the first time the unique roles of Dectin-2 and Dectin-1 in triggering Syk-JNK to activate signal 1 and 2 for H. capsulatum-induced NLRP3 inflammasome activation.

The switch between latency and the lytic cycle of Kaposi’s sarcoma-associated herpesvirus (KSHV) is controlled by the expression of virally encoded ORF50 protein. Thus far, the regulatory mechanism underlying the protein stability of ORF50 is unknown. Our earlier studies have demonstrated that a protein abundance regulatory signal (PARS) at the ORF50 C-terminal region modulates its protein abundance. The PARS region consists of PARS-I (aa 490–535) and PARS-II (aa 590–650), and mutations in either component result in abundant expression of ORF50. Here, we show that ORF50 protein is polyubiquitinated and its abundance is controlled through the proteasomal degradation pathway. The PARS-I motif mainly functions as a nuclear localization signal in the control of ORF50 abundance, whereas the PARS-II motif is required for the binding of ubiquitin enzymes in the nucleus. We find that human oncoprotein MDM2, an ubiquitin E3 ligase, is capable of interacting with ORF50 and promoting ORF50 degradation in cells. The interaction domains between both proteins are mapped to the PARS region of ORF50 and the N-terminal 220-aa region of MDM2. Additionally, we identify lysine residues at positions 152 and 154 in the N-terminal domain of ORF50 critically involved in MDM2-mediated downregulation of ORF50 levels. Within KSHV-infected cells, the levels of MDM2 were greatly reduced during viral lytic cycle and genetic knockdown of MDM2 in these cells favored the enhancement of ORF50 expression, supporting that MDM2 is a negative regulator of ORF50 expression. Collectively, the study elucidates the regulatory mechanism of ORF50 stability and implicates that MDM2 may have a significant role in the maintenance of viral latency by lowering basal level of ORF50.

Single crystal semiconductor nanomembranes (NM) are important in various applications such as heterogeneous integration and flexible devices. This paper reports the fabrication of AlGaN/GaN NMs and NM high electron mobility transistors (HEMT). Electrochemical etching is used to slice off single-crystalline AlGaN/GaN layers while preserving their microstructural quality. A double heterostructure design with a symmetric strain profile is employed to ensure minimal residual strain in freestanding NMs after release. The mobility of the two-dimensional electron gas (2DEG), formed by the AlGaN/GaN heterostructure, is noticeably superior to previously reported values of many other NMs. AlGaN/GaN nanomembrane HEMTs are fabricated on SiO2 and flexible polymeric substrates. Excellent electrical characteristics, including a high ON/OFF ratio and transconductance, suggest that III-Nitrides nanomembranes are capable of supporting high performance applications.