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Abstract Nanohybrids consisting of graphene and colloidal semiconductor quantum dots (QDs/graphene) can combine the benefits of strong quantum confinement in the constituent components, such as high carrier mobility in graphene and large exciton binding energy in QDs, to enable extraordinary photoconductive gain and hence high photoresponse. Furthermore, QDs/graphene nanohybrids are inherently flexible, making them ideal for flexible photodetectors. Despite exciting progress made in rigid and flexible QDs/graphene photodetectors in broadband from UV to short-wave infrared, flexible middle-wave infrared (MWIR) photodetectors remain a challenge. Herein, we report the first success in fabrication of HgTe QDs/graphene nanohybrid ultrabroadband (400–4000 nm wavelength) photodetectors on flexible polyimide substrates via resolving critical issues of device fabrication on flexible substrates, which allowed flexible device performance approaching their counterparts on rigid substrates. Specifically, the flexible HgTe QDs/graphene nanohybrids photodetectors exhibited high responsivity (R*) across the ultrabroadband spectrum at room temperature. At 550 nm, 1.5 μm and 4.0 μm wavelengths, anR* of up to 0.65 AW⁻¹, 5.7 × 10⁻³AW⁻¹and 0.9 × 10⁻³AW⁻¹were achieved respectively. Bending tests confirmed performance stability of the flexible HgTe QDs/graphene nanohybrids photodetectors under repeated bending with up to 5.5 mm radius of curvature. Images taken in the ultrabroadband while the photodetectors in flat and bent states both show promising imaging quality. This result illustrates the potential applications of the uncooled, flexible HgTe QDs/graphene nanohybrids photodetectors in the ultrabroadband range of 400–4000 nm. 

ABSTRACT Actin microfilaments (F-actin) serve as tracks for myosin-driven organelle movement in plants. To understand how the F-actin network supports organelle movement, we examined the motility of peroxisomes as a common proxy for overall organelle motility in Arabidopsis thaliana. Using mutants of three villin (VLN) genes encoding major actin-bundling proteins that are actively expressed in vegetative tissues, we found that the vln4 mutation exacerbated the growth and subcellular F-actin defects in the vln2 vln3 double mutant. Compared to wild-type cells, the double and triple vln mutants exhibited progressive reduction of stable F-actin bundles and rapid remodeling of the fine filaments into a dynamic mesh. The defective F-actin organization caused significantly reduced mean speed and displacement distance of peroxisomes, although both rapid and slow movements were observed. Correlation analysis grouped complex heterogeneous peroxisome movement patterns into clusters reflecting distinct movement patterns. The vln2 vln3 vln4 triple mutant had significantly fewer peroxisomes with long-range and linear movement but produced an actin mesh network sufficient to retain basal peroxisome function. Our results provide insights into how VLN-dependent F-actin organization is coupled with the complex patterns of actomyosin-mediated organelle movement. 

Abstract The movement, distribution, and interactions of organelles are cell-type specific, responding to fluctuating metabolic and environmental cues and governing the efficiency of plant physiology and stress response. The directional motility of various plant organelles is predominantly driven by the actomyosin system, yet the distinct functionality of these organelles across plant tissues presupposes organelle-specific regulation of motility, which requires the detection of subtle shifts in dynamics. Meanwhile, studies that comprehensively characterize and directly compare the simultaneous movement of multiple types of organelles within the same cell are limited. Here, we visualized peroxisomes, mitochondria, chloroplasts, Golgi bodies, and actin filaments simultaneously in tobacco (Nicotiana tabacum) to evaluate organelle organization and motility within the context of one another. Quantitative analysis of multiple motility factors enabled us to identify peroxisome motility in tobacco mesophyll as distinct from other organelles. Further analysis in Arabidopsis (Arabidopsis thaliana) revealed that both mitochondria and peroxisomes are slower in mesophyll cells compared to epidermis in normal growth conditions, but their motility patterns are unique from one another across leaf tissue after plants experienced conditions that induce photorespiration, a metabolic pathway requiring the concerted action of chloroplasts, peroxisomes, and mitochondria. Our quantitative analysis of thousands of organelles across species, cell type, and physiological conditions unveils distinct modulation of motility according to organelle identity and function. The extensive combinatorial characterizations of plant organelle movement provide a fundamental resource for the future discovery of molecular mechanisms driving the movement and distribution of diverse organelles. 

Abstract Nanohybrids based on van der Waals (vdW) heterostructures of graphene (Gr) decorated with MoS₂nanodiscs (MoS₂-NDs) combine the advantages of high carrier mobility of graphene for high photoconductive gain and localized surface plasmonic resonance (LSPR) on MoS₂-NDs for enhanced light absorption. Considering MoS₂-NDs are obtained using dip-coating of (NH₄)₂MoS₄precursor followed with annealing in sulfur vapor at 450 °C, the annealing plays a critical role in controlling the MoS₂-NDs properties. This work investigated the effect of the annealing time on the MoS₂-NDs dimension and found the MoS₂-ND’s thickness was increased monotonically from bilayer to multilayer and diameter reduced from ∼900 nm to 600 nm with annealing time increased from 4 to 25 min. A similar increasing photoresponsivity observed on MoS₂-NDs/Gr with annealing time indicates the conversion of the (NH₄)₂MoS₄precursor to crystalline MoS₂initiated at the precursor/graphene interface and continued vertically. At the annealing time of ∼20 min, the MoS₂-NDs reached the optimal diameter (∼600 nm) and thickness (near or slightly above 4.2 nm) for LSPR while graphene remained unblemished, yielding the highest photoresponsivity up to 37 A W⁻¹(at 550 nm wavelength and 12 μW cm⁻²light intensity) on the MoS₂-NDs/Gr nanohybrids photodetectors which leads to enhanced detectivityD* by a factor of 320 over the quantum dots/graphene nanohybrid counterpart of comparable thickness and illustrates the benefits of LSPR induced in MoS₂-NDs for enhanced light absorption. 

Deep learning models are widely used in decision-making and recommendation systems, where they typically rely on the assumption of a static data distribution between training and deployment. However, real-world deployment environments often violate this assumption. Users who receive negative outcomes may adapt their features to meet model criteria, i.e., recourse action. These adaptive behaviors create shifts in the data distribution and when models are retrained on this shifted data, a feedback loop emerges: user behavior influences the model, and the updated model in turn reshapes future user behavior. Despite its importance, this bidirectional interaction between users and models has received limited attention. In this work, we develop a general framework to model user strategic behaviors and their interactions with decision-making systems under resource constraints and competitive dynamics. Both the theoretical and empirical analyses show that user recourse behavior tends to push logistic and MLP models toward increasingly higher decision standards, resulting in higher recourse costs and less reliable recourse actions over time. To mitigate these challenges, we propose two methods—Fair-top-k and Dynamic Continual Learning (DCL)—which significantly reduce recourse cost and improve model robustness. Our findings draw connections to economic theories, highlighting how algorithmic decision-making can unintentionally reinforce a higher standard and generate endogenous barriers to entry. 

ABSTRACT Plant cytokinesis results in the formation of the cell plate by the phragmoplast which contains dynamic microtubules serving as the track for the delivery of cell wall builders included in Golgi vesicles. During the centrifugal process of cell plate assembly, new microtubules are assembled and bundled at the leading edge to prepare for vesicle transport while older microtubules are disassembled at the lagging edge upon the completion of vesicle delivery. The turnover of phragmoplast microtubules in this process is thought to be regulated by phosphorylation of the key microtubule bundling factor MAP65. A recent study revealed a surprising role of theα‐Aurora kinase, which is typically known for its role in governing the formation of the bipolar spindle apparatus, in phosphorylating the primary microtubule bundler MAP65‐3 in Arabidopsis. This phosphorylation positively contributes to the expansion of the phragmoplast. The phragmoplast midzone is also the hub for other cytokinesis‐important kinases. It is intriguing how these kinases are targeted and how they may crosstalk with each other to orchestrate the expansion of the phragmoplast. 

Abstract The evolutionarily conserved microspherule protein 1 (MCRS1) has diverse functions, ranging from transcriptional regulation to stabilization of microtubule minus ends in acentrosomal spindles in mammals. A previous study suggested that in the model plant Arabidopsis thaliana, inactivation of an MCRS1 homolog gene led to aborted embryogenesis. To test whether this lethality was caused solely by sporophytic defects, we used the heterozygous emb1967-1/mcrs1-1 mutant for reciprocal crosses with the wild-type plant and found that the MCRS1 gene was dispensable for the development of both male and female gametophytes. An MCRS1–GFP fusion protein was expressed in the mcrs1 mutant and suppressed the mutation as evidenced by restored growth. This functional fusion protein exclusively localized to interphase nuclei and became unnoticeable during mitosis before reappearing in the reforming daughter nuclei. Affinity purification of the MCRS1–GFP protein specifically recovered the Myb-like transcription factor DRMY1 (Development Regulated Myb-like 1) but not microtubule-associated factors. Direct MCRS1–DRMY1 interaction was also demonstrated by a localization-based assay in living cells. Thus, we hypothesized that MCRS1’s function was perhaps linked to transcription factors like DRMY1 and its paralog DP1 for regulation of gene expression during sporophyte development. 

ABSTRACT Actin microfilaments (F-actin) serve as the track for directional movement of organelles in plant cells. In actively growing plant cells, F-actin often form robust bundles that trespass the cellular dimension. To test how the F-actin network was employed for peroxisome movement, we wished to disturb actin organization by genetically compromising the function of villin (VLN) proteins that serve as the primary bundling factor inArabidopsis thalianacells. To do so, we isolated T-DNA insertional mutants in threeVLNgenes that were most actively expressed in vegetative tissues. We found that thevln4mutation greatly enhanced the growth defects caused by thevln2 vln3double mutant as thevln2 vln3 vln4triple mutant had a great reduction of organ growth and formed heavily deformed tissues. Both VLN2 and VLN4 proteins were detected on bundled F-actin filaments. Compared to the wild-type cells, the double and triple mutants exhibited progressively reduction of stable F-actin bundles and had fine F-actin filaments undergo rapid remodeling. The defective F-actin network did not prevent peroxisomes from taking on both rapid and slow movements along the F-actin tracks. However, we found that compromised F-actin bundling caused significant reductions in the speed of peroxisome movement and the displacement distance of peroxisome positions. Using a correlation analysis method, we also demonstrated that the complex heterogeneous peroxisome movement may be classified into clusters reflecting the directionality of peroxisome movement. The triple mutant suffered from a significant reduction of peroxisomes exhibiting long-range and linear movement. Our results provided insights into how VLN-dependent F-actin organization was coupled with the complex patterns of peroxisome movement.