MicroRNAs (miRNA) families act as critical regulators for plant growth, development, and responses to abiotic stresses. In this study, we characterized TaemiR408, a miRNA family member of wheat (Triticum aestivum), for the role in mediating plant responses to Pi starvation and salt stress. TaemiR408 targets six genes that encode proteins involving biochemical metabolism, microtubule organization, and signaling transduction. 5′- and 3′-RACE analyses confirmed the mRNA cleavage of target genes mediated by this wheat miRNA. TaemiR408 showed induced expression patterns upon Pi starvation and salt stress and whose upregulated expression was gradually repressed by the normal recovery treatments. The target genes of TaemiR408 exhibited reverse expression patterns to this miRNA, whose transcripts were downregulated under Pi starvation and salt stress and the reduced expression was recovered by the followed normal condition. These results suggest the regulation of the target genes under TaemiR408 through a cleavage mechanism. Tobacco lines with TaemiR408 overexpression exhibited enhanced stress tolerance, showing improved phenotype, biomass, and photosynthesis behavior compared with wild type under both Pi starvation and salt treatments, which closely associate increased P accumulation upon Pi deprivation and elevated osmolytes under salt stress, respectively. Phosphate transporter (PT) gene NtPT2 displays upregulated transcripts in the Pi-deprived TaemiR408 overexpressors; knockdown of this PT gene reduces Pi acquisition under low-Pi stress, confirming its role in improving plant Pi taken up. Likewise, NtPYL2 and NtSAPK3, genes encoding abscisic acid (ABA) receptor and SnRK2 protein, respectively, exhibited upregulated transcripts in salt-challenged TaemiR408 overexpressors; knockdown of them caused deteriorated growth and lowered osmolytes amounts of plants upon salt treatment. Thus, TaemiR408 is crucial for plant adaptations to Pi starvation and salt stress through regulating Pi acquisition under low-Pi stress and remodel ABA signaling pathway and osmoprotects biosynthesis under salt stress.

Artificial synapses and neurons are two critical, fundamental bricks for constructing hardware neural networks. Owing to its high-density integration, outstanding nonlinearity, and modulated plasticity, memristors have attracted emerging attention on emulating biological synapses and neurons. However, fabricating a low-power and robust memristor-based artificial neuron without extra electrical components is still a challenge for brain-inspired systems. In this work, we demonstrate a single two-dimensional (2D) MXene(V2C)-based threshold switching (TS) memristor to emulate a leaky integrate-and-fire (LIF) neuron without auxiliary circuits, originating from the Ag diffusion-based filamentary mechanism. Moreover, our V2C-based artificial neurons faithfully achieve multiple neural functions including leaky integration, threshold-driven fire, self-relaxation, and linear strength-modulated spike frequency characteristics. This work demonstrates that three-atom-type MXene (e.g., V2C) memristors may provide an efficient method to construct the hardware neuromorphic computing systems.

Wheat miRNA member TaMIR1139 targets genes functional in various families and plays crucial roles in regulating plant Pi starvation tolerance. Through regulating target genes at posttranscriptional or translational level, plant miRNAs are involved in mediating diverse biological processes associated with growth, development, and responses to adverse stresses. In this study, we characterized the expression pattern and function of TaMIR1139, a miRNA member of wheat (T. aestivum) under Pi deprivation. TaMIR1139 precursor is also present in N. tabucum, suggesting the conserved nature of miR1139 across monocots and eudicots. TaMIR1139 targets seven genes within different families. The transcripts abundance of TaMIR1139 was induced upon Pi deprivation and the upregulated expression under Pi starvation was downregulated by the Pi recovery treatment, In contrast, the genes targeted by TaMIR1139 exhibited reduced transcripts upon Pi starvation and their downregulated expression was recovered by Pi-recovery condition, suggesting the regulation of them under TaMIR1139 through a cleavage mechanism. TaMIR1139 overexpression conferred the Pi-deprived plants improved phenotype, biomass, photosynthesis, and Pi acquisition. Transcriptome analysis identified numerous genes involving biological process, cellular components, and molecular function were differentially expressed in the TaMIR1139 overexpression lines, which suggests the TaMIR1139-mediated plant Pi starvation tolerance to be associated with the role of miRNA in extensively modulating the transcript profiling. A phosphate transporter (PT) gene NtPT showed significantly upregulated expression in TaMIR1139 overexpression lines; overexpression of it conferred plants improved Pi acquisition upon Pi starvation, suggesting its contribution to the TaMIR1139-mediated plant low-Pi stress resistance. Our investigation indicates that TaMIR1139 is critical in plant Pi starvation tolerance through transcriptionally regulating the target genes and modulating the Pi stress-defensiveness processes.

Near-infrared (NIR) photodetectors play an irreplaceable role in many fields, such as aerospace, astronomy, meteorology, military, civil and industry. Among them, NIR organic photodetectors (OPDs) have attracted widespread attention due...

OPDs have been proved. [12][13][14][15] For instance, a NIR OPD based polymer donor (PD004) achieved an a detectivity of 6.6 × 10 12 Jones at 1030 nm, and a response time of 9.8 µs. [16] Also, Huang et al. reported the OPD based on PTB7-Th:IEICO-4F with the spectral response covering 300-1000 nm, a detectivity of 5.1 × 10 13 Jones at 930 nm. [17] Such a high detectivity in NIR range was attributed to low-bandgap donor with high absorption coefficient and matched energy levels of the device. Apart from high detectivity, photodetectors also require fast response at low operating voltage. However, it is rarely reported about the wide spectrum photodetectors with fast response speed in the NIR range. [18,19] The high response speed was attributed to the excellent charge transport and extraction of photogenerated carriers. Hence, we aim to develop suitable low-bandgap donor materials with high absorption coefficients and high carrier mobility.Aza-BODIPY derivatives have been intensively investigated as photosensitizing agents and light-harvesters due to their high molar extinction coefficients and tunable bandgap properties. [20][21][22][23][24] Meanwhile, the aza-BODIPY derivatives have been reported to exhibit high hole migration. [25,26] Employing the p-type aza-BODIPY dyes as the activity layer, the hole mobility (up to 0.018 cm 2 V -1 s -1 ) of the film devices fabricated by solution process has been reported by Pei et al. [26] This might improve charge transport and extraction of the activity layer. Meanwhile, in order to obtain low bandgap and broaden absorption spectrum, conjugated polymer with narrow bandgaps should be constructed. Owing to the square planar x y 2 2 d − orbitals, [24,27] platinum(II)-acetylide conjugated polymers usually exhibit more extended π-electron delocalized system, which can broaden absorption bands and narrow bandgap, and might provide an excellent strategy to develop narrow-bandgap donor materials. [27][28][29] Therefore, we introduced aza-BODIPY moieties into platinum(II)-acetylide conjugated polymers.Herein, a novel narrow-bandgap platinum(II)-acetylide conjugated polymer (BODIPY-Pt) containing NIR-absorbing aza-BODIPY moieties has been designed and synthesized by dehydrohalogenation reaction of trans-Pt(PBu 3 ) 2 Cl 2 and aza-BODIPY units (Scheme 1). The obtained polymer BODIPY-Pt was adopted as the active layer to fabricate photodetectors. Benefitting from the NIR optical sensitivity, the OPDs exhibited high EQE in the NIR region (mostly beyond 15%). Simultaneously, Broadband photodetectors have driven the development of optical communication, image sensing, and health monitoring technologies, yet confronting a challenge in acquiring high performance in the whole spectral range. Herein, a novel low-bandgap platinum(II)-acetylide conjugated polymer is designed and synthesized by introducing near-infrared-absorbing aza-BODIPY moieties. Benefiting from the good solubility and extended conjugated systems, it can serve as the donor materials for photodetector. By blending with (6,6)-...

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In this paper, a novel miniaturized wideband planar bow-tie slot antenna is proposed. For the purpose of miniaturization and wide bandwidth, the effects of the dimension and shape of the bow-tie slot and feed structure are analyzed. This antenna adopts a water droplet slot, fed by an optimized asymmetric coplanar waveguide (CPW). By adjusting the feeding line, the impedance characteristic of the antenna is greatly improved that leads to a broader bandwidth. The proposed antenna operates from 2.8 GHz to 5.25 GHz with a gain of 3.8 dB. Compared with the traditional triangle bow-tie antenna, the relative bandwidth of the proposed antenna is broadened to more than 61%, while the size is reduced by about 36%, which indicates the proposed antenna is suitable for a variety of wireless applications.

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