DNAzymes have been recognized as promising transducing agents for visualizing endogenous biomarkers, but their inefficient intracellular delivery and limited amplification capacity (including ...insufficient cofactor supply) preclude their extensive biological application. Herein, an autocatalytic DNAzyme (ACD) biocircuit is constructed for amplified microRNA imaging in vivo based on a hybridization chain reaction (HCR) and DNAzyme biocatalysis, sustained by a honeycomb MnO2 nanosponge (hMNS). The hMNS not only delivers DNA probes, but also supplies Mn2+ as a DNAzyme cofactor and magnetic resonance imaging (MRI) agent. Through the subsequent cross‐activation of HCR and DNAzyme amplicons, the ACD amplifies the limited signal resulting from miRNA recognition. The hMNS/ACD system was used to image microRNA in vivo, thus demonstrating its great promise in cancer diagnosis.
An autocatalytic circuit is constructed for in vivo fluorescence/molecular resonance imaging based on a hybridization chain reaction (HCR) and DNAzyme biocatalysis, sustained by a honeycomb MnO2 nanosponge (hMNS). The hMNS was not only used to deliver the DNA, but also to supply the DNAzyme with Mn2+ as a cofactor. This system was used to detect microRNA in vivo and shows great promise in cancer diagnosis.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
The energy hub is a powerful conceptualization of how to acquire, convert, and distribute energy resources in the smart city. However, uncertainties such as intermittent renewable energy injection ...present challenges to energy hub optimization. This paper solves the optimal energy flow of adjacent energy hubs to minimize the energy costs by utilizing the flexibility of energy resources in a smart city with uncertain renewable generation. It innovatively models the power and gas flows between hubs using chance constraints, thus permitting the temporary overloading acceptable on real energy networks. This novelty not only ensures system security but also helps reduce or defer network investment. By restricting the probability of chance constraints over a specific level, the energy hub optimization is formulated as a multiperiod stochastic problem with the total generation cost as the objective. Cornish-Fisher expansion is utilized to incorporate the chance constraints into the optimization, which transforms the stochastic problem into a deterministic problem. The interior-point method is then applied to resolve the developed model. The proposed chance-constrained optimization is demonstrated on a three-hub system and results extensively illustrate the impact of chance constraints on power and gas flows. This work can benefit energy hub operators by maximizing renewable energy penetration at the lowest cost in a smart city.
The therapeutic performance of DNAzyme‐involved gene silencing is significantly constrained by inefficient conditional activation and insufficient cofactor supply. Herein, a self‐sufficient ...therapeutic nanosystem was realized through the delicate design of DNAzyme prodrugs and MnO2 into a biocompatible nanocapsule with tumor‐specific recognition/activation features. The indocyanine green (ICG)‐modified DNA prodrugs are designed by splitting the DNAzyme and then reconstituted into the exquisite catalyzed hairpin assembly (CHA) amplification circuit. Based on the photothermal activation of ICG, the nanocapsule was disassembled to expose the MnO2 ingredient which was immediately decomposed into Mn2+ ions to supplement an indispensable DNAzyme cofactor on‐demand with a concomitant O2 generation for enhancing the auxiliary phototherapy. The endogenous microRNA catalyzes the amplified assembly of DNA prodrugs via an exquisite CHA principle, leading to the DNAzyme‐mediated simultaneous silencing of two key tumor‐involved mRNAs. This self‐activated theranostic nanocapsule could substantially expand the toolbox for accurate diagnosis and programmable therapeutics.
A self‐sufficient therapeutic photo‐gene therapy nanosystem was realized through the delicate design of DNAzyme prodrugs and MnO2 adjuvant into nanocapsule with tumor‐specific recognition/activation features.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Online teaching transition during COVID-19 school lockdown elicited challenges for teachers and schools across the globe. The existing literature on the impact of COVID-19 in the education sector is ...predominantly descriptive and focused on the difficulties faced by teachers during the process of transferring into online teaching, mainly in the higher education sector. This study adopted a mixed-method design to examine online teaching self-efficacy (TSE) during COVID-19, its associated factors and moderators. A sample of 351 Chinese school teachers retrospectively reported their online TSE at the beginning and end of COVID-19 school lockdown, out of which six were followed up for an in-depth interview. TSE for online instruction did not significantly increase (β = .014,
p
> 0.05) whereas that for technology application increased significantly (β = .231,
p
< 0.01). Lack of experience in online teaching, separation of teachers from students, school administrative process and unsatisfactory student academic performance were identified as the major associated factors. A moderation effect of adaptability and teacher burnout on the change in online TSE were examined, of which passion burnout was the only significant moderator toward the change in online TSE. The study thus concluded that teachers’ online TSE for technology application increased among Chinese teachers during COVID-19 school lockdown.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Lowly expressed analyte in complex cytoplasmic milieu necessitates the development of non‐enzymatic autocatalytic DNA circuits with high amplification and anti‐interference performance. Herein, we ...engineered a versatile and robust stimuli‐responsive autocatalytic hybridization assembly (AHA) circuit for high‐performance in vivo bioanalysis. Under a moderately confined condition, the initiator motivated the autonomous and cooperative cross‐activation of cascade hybridization reaction and catalytic DNA assembly for generating an exponentially amplified readout without the parasite steric hindrance and random diffusion side effects. The AHA circuit was systematically investigated by a series of experimental studies and theoretical simulations. The successively guaranteed target recognition and synergistically accelerated signal‐amplification enabled the sensitive and selective detection of analyte, and realized the robust miRNA imaging in living cells and mice. This autocatalytic DNA circuit could substantially expand the toolbox for accurate diagnosis and programmable therapeutics.
A self‐reproducing dandelion‐like autocatalytic hybridization assembly (AHA) circuit was proposed for in vivo amplified bioimaging research where the initiator promoted the autonomous cross‐activation of the cascade hybridization reaction (CHR) and catalytic DNA assembly (CDA) components.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK
Phase unbalance is widespread in the distribution networks in the UK, continental Europe, US, China, and other countries and regions. This paper first reviews the mass scale of phase unbalance and ...its causes and consequences. Three challenges arise from phase rebalancing: the scalability, data scarcity, and adaptability (towards changing unbalance over time). Solutions to address the challenges are: 1) using retrofit table, maintenance-free, automatic solutions to overcome the scalability challenge; 2) using data analytics to overcome the data-scarcity challenge; and 3) using phase balancers or other online phase rebalancing solutions to overcome the adaptability challenge. This paper categorizes existing phase rebalancing solutions into three classes: 1) load/lateral re-phasing; 2) using phase balancers; 3) controlling energy storage, electric vehicles, distributed generation, and micro-grids for phase rebalancing. Their advantages and limitations are analyzed and ways to overcome their limitations are recommended. Finally, this paper suggests future research topics: 1) long-term forecast of phase unbalance; 2) the whole-system analysis of the unbalance-induced costs; 3) the phase unbalance diagnosis for data-scarce LV networks; 4) techno-commercial solutions to exploit the flexibility from large three-phase customers for phase balancing; 5) the optimal placement of phase balancers; 6) the transition from single-phase customers to three-phase customers.
Uneven load distribution leads to a 3-phase imbalance at the low voltage (LV) substation level. This imbalance has distinct impacts on main feeders and LV transformers: for main feeders, it reduces ...the available capacity as the phase with the least spare capacity determines the usable capacity; for LV transformers, phase imbalance reduces the available capacity due to additional power along the neutral line. To assess the additional reinforcement cost (ARC) arising from a 3-phase imbalance, this paper proposes two novel costing models for main feeders and LV transformers respectively. Each model involves the derivation of an accurate ARC formula based on the degree of three-phase imbalance and a linearized approximation through Taylor's expansion to simplify the detailed ARC formula, enabling quantification of future LV investment in scale. The developed models are tested on 4 cases where imbalance ranges from 0 to 10%, and reveals that i) a small imbalance degree may cause a substantial ARC on main feeders; ii) ARC grows exponentially as asset utilization is close to its capacity; and that iii) a main feeder is more sensitive to its respective imbalance degree than an LV transformer under the same condition. The models serve as an effective tool to assist distribution network operators (DNOs) to quantify a key cost (ARC) element from the phase imbalance, allowing DNOs to evaluate their future LV investment in scale.
This article investigates the utilization of a consequent-pole (CP) rotor design in the interior permanent magnet (IPM) motor to enhance the permanent magnet (PM) utilization ratio material and ...reduce leakage flux. Compared to the spoke-type IPM motor, the proposed rotor design utilizes a strong flux-focusing effect to improve performance. The evolutionary mechanism of the proposed flux-focusing rotor from flat-type and spoke-type IPM rotors is illustrated, resulting in a higher PM utilization ratio. The multiobjective genetic algorithm is employed to optimize the design of the proposed CP motor, aiming to maximize the PM material utilization while minimizing torque ripple. The optimization process begins with sensitivity analysis, exploring geometric variables of the rotor and determining their respective ranges and step sizes. Furthermore, a set of Pareto front are generated to identify optimal outcome. Finite element analysis is utilized to compare the electromagnetic performance of the two motors. The obtained results indicate that the proposed structure achieves 2.1% increase in output torque and reduction of approximately 40.2% in PM volume compared to the spoke-type motor. Finally, a 3000 r/min 10 kW prototype was manufactured and tested for confirming the effectiveness of the proposed configuration.
In this paper, a two-stage optimal charging scheme based on transactive control is proposed for the aggregator to manage day-ahead electricity procurement and real-time electric vehicles (EV) ...charging management in order to minimize its total operating cost. The day-ahead electricity procurement considers both the day-ahead energy cost and expected real-time operation cost. In the real-time charging management, the cost of employing the charging flexibility from the EV owners is explicitly modeled. The aggregator uses a transactive market to manage the real-time charging demand to provide the regulating power. A model predictive control-based method is proposed for the aggregator to clear the transactive market. The real-time charging decisions of the EVs are determined by the clearing of the proposed transactive market according to the real-time requests and preferences of the EV owners. As such, the aggregators decisions in the real-time EV charging management and regulating power markets can be optimized. At the same time, the charging requirements and response preferences of the EV owners are respected. Case studies using real world driving data from the Danish National Travel Surveys were conducted to verify the proposed framework.
Nanobactericides represent one of the most efficient and promising strategies for eliminating bacterial infection considering the increasing resistance threats of conventional antibiotics. Black ...phosphorus (BP) is the most exciting postgraphene layered 2D nanomaterial with convincing physiochemical properties, yet the study of BP‐based antibiotics is still in its infancy. Here, a compact silver nanoparticle (AgNP)–doped black phosphorus nanosheet (BPN) is constructed to synergistically enhance solar disinfection through the promoted reactive oxygen species (ROS) photogeneration, which is attributed to the improved electron–hole separation and recombination of BPNs as revealed from the systematic experimental studies. An in‐depth density functional theory (DFT) calculation confirms that the integrated AgNPs provide a preferred site for facilitating the adsorption and activation of O2, thus promoting the more efficient and robust ROS generation on BPN–AgNP nanohybrids. Besides the enhanced photoinduced ROS, the anchored AgNPs simultaneously lead to a dramatically increased affinity toward bacteria, which facilitates a synergetic pathogen inactivation. Significantly, the convincing antimicrobial BPN–AgNP contributes to the prominent wound healing and antimicrobial ability in vivo with minimized biological burden. This sophisticated design of new 2D nanohybrids opens a new avenue for further exploiting BP‐based nanohybrids in portable bandage and broad‐spectrum disinfection applications.
An intelligent silver nanopaticle (AgNP)‐doped black phosphorus nanosheet (BPN‐AgNP) nanohybrid is facilely assembled for efficient bacteria inactivation via photocatalytic generation of reactive oxygen species (ROS). The intrinsic antibacterial BPN‐AgNP nanohybrid show rapid wound healing and synergistically promotes antibacterial performance in vivo, and thus holds great potential in pathogen infection therapy.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SAZU, SBCE, SBMB, UL, UM, UPUK