Recent Advances in Patterning Strategies for Full‑Color Perovskite Light‑Emitting Diodes

Metal halide perovskites have emerged as promising light-emitting materials for next-generation displays owing to their remarkable material characteristics including broad color tunability,pure color emission with remarkably narrow bandwidths,high quantum yield,and solution processability.Despite recent advances have pushed the luminance efficiency of monochromic perovskite light-emitting diodes(PeLEDs)to their theoretical limits,their current fabrication using the spincoating process poses limitations for fabrication of full-color displays.To integrate PeLEDs into full-color display panels,it is crucial to pattern red–green–blue(RGB)perovskite pixels,while mitigating issues such as cross-contamination and reductions in luminous efficiency.Herein,we present state-of-the-art patterning technologies for the development of full-color PeLEDs.First,we highlight recent advances in the development of efficient PeLEDs.Second,we discuss various patterning techniques of MPHs(i.e.,photolithography,inkjet printing,electron beam lithography and laserassisted lithography,electrohydrodynamic jet printing,thermal evaporation,and transfer printing)for fabrication of RGB pixelated displays.These patterning techniques can be classified into two distinct approaches:in situ crystallization patterning using perovskite precursors and patterning of colloidal perovskite nanocrystals.This review highlights advancements and limitations in patterning techniques for PeLEDs,paving the way for integrating PeLEDs into full-color panels.

Recent advances in soft electronic materials for intrinsically stretchable optoelectronic systems

In recent years,significant progress has been achieved in the design and fabrication of stretchable optoelectronic devices.In general,stretchability has been achieved through geometrical modifications of device components,such as with serpentine interconnects or buckled substrates.However,the local stiffness of individual pixels and the limited pixel density of the array have impeded further advancements in stretchable optoelectronics.Therefore,intrinsically stretch-able optoelectronics have been proposed as an alternative approach.Herein,we review the recent advances in soft elec-tronic materials for application in intrinsically stretchable optoelectronic devices.First,we introduce various intrinsically stretchable electronic materials,comprised of electronic fillers,elastomers,and surfactants,and exemplify different in-trinsically stretchable conducting and semiconducting composites.We also describe the processing methods used to fabricate the electrodes,interconnections,charge transport layers,and optically active layers used in intrinsically stretch-able optoelectronic devices.Subsequently,we review representative examples of intrinsically stretchable optoelectronic devices,including light-emitting capacitors,light-emitting diodes,photodetectors,and photovoltaics.Finally,we briefly discuss intrinsically stretchable integrated optoelectronic systems.

Manganese-Based Catalysts for Indoor Volatile Organic Compounds Degradation with Low Energy Consumption and High Efficiency

With the development of industrialization,the emission of volatile organic compounds(VOCs)to atmosphere causes serious environmental problems and the treatment of VOCs needs to consume a lot of energy.Moreover,indoor VOCs are seriously harmful to human health.Thus,there is an urgent requirement for the development of indoor VOCs treatment technologies.Catalytic degradation of VOCs,as a low energy consumption,high efficiency,and easy to achieve manner,has been widely studied in related fields.As a kind of transition metal catalyst,manganese-based catalysts have attracted a lot of attention in the catalytic degradation of VOCs because of their unique advantages including high efficiency,low cost,and excellent stability.This paper reviews the state-of-the-art progress of manganese-based catalysts for VOCs catalytic degradation.We introduce the thermocatalytic,photocatalytic and photo-thermocatalytic degradation of VOCs on manganese-based catalysts in this paper.The optimization of manganese-based catalysts by means of structural design,decorating modification and defect engineering is discussed.

Recent progress in production and usage of hydrogen peroxide

Hydrogen peroxide has attracted increasing interest as an environmentally benign and green oxidant that can also be used as a solar fuel in fuel cells.This review focuses on recent progress in production of hydrogen peroxide by solar-light-driven oxidation of water by dioxygen and its usage as a green oxidant and fuel.The photocatalytic production of hydrogen peroxide is made possible by combining the e^(-)and 4e-oxidation of water with the e^(-)reduction of dioxygen using solar energy.The catalytic control of the selectivity of the e^(-)vs.4e-oxidation of water is discussed together with the selectivity of the e^(-)vs.4e-reduction of dioxygen.The combination of the photocatalytic e^(-)oxidation of water and the e^(-)reduction of dioxygen provides the best efficiency because both processes afford hydrogen peroxide.The solar-light-driven hydrogen peroxide production by oxidation of water and by reduction of dioxygen is combined with the catalytic oxidation of substrates with hydrogen peroxides,in which dioxygen is used as the greenest oxidant.

Protein interaction network related to Helicobacter pylori infection response

AIM:To understand the complex reaction of gastric inflammation induced by Helicobacter pylori(H pylori) in a systematic manner using a protein interaction network. METHODS:The expression of genes significantly changed on microarray during H pylori infection was scanned from the web literary database and translated into proteins.A network of protein interactions was constructed by searching the primary interactions of selected proteins.The constructed network was mathematically analyzed and its biological function was examined.In addition,the nodes on the network were checked to determine if they had any further functional importance or relation to other proteins by extending them. RESULTS:The scale-free network showing the relationship between inflammation and carcinogenesis was constructed.Mathematical analysis showed hub and bottleneck proteins,and these proteins were mostly related to immune response.The network contained pathways and proteins related to H pylori infection,such as the JAK-STAT pathway triggered by interleukins.Activation of nuclear factor (NF)-κB,TLR4,and other proteins known to function as core proteins of immune response were also found. These immune-related proteins interacted on the network with pathways and proteins related to the cell cycle,cell maintenance and proliferation,andtranscription regulators such as BRCA1,FOS,REL,and zinc finger proteins.The extension of nodes showed interactions of the immune proteins with cancer- related proteins.One extended network,the core network,a summarized form of the extended network, and cell pathway model were constructed. CONCLUSION:Immune-related proteins activated by H pylori infection interact with proto-oncogene proteins.The hub and bottleneck proteins are potential drug targets for gastric inflammation and cancer.

Magnetic resonance imaging of the pancreas in streptozotocin-induced diabetic rats: Gadofluorine P and Gd-DOTA

AIM: To investigate the performance of Gadofluorine P-enhanced magnetic resonance imaging(MRI) on the diagnosis of diabetes in a streptozotocin(STZ)-induced diabetic rat model.METHODS: Fischer 344 rats were treated with STZ.Rats not treated with STZ served as controls. T1-weighted MRI was performed using a 3T scanner before and after the injection of Gd-DOTA or Gadofluorine P(6 diabetic rats, 5 controls). The normalized signal intensity(SI) and the enhancement ratio(ER) of the pancreas were measured at each time point, and the values were compared between the normal and diabetic rats using the Mann-Whitney test. In addition,the values were correlated with the mean islet number.Optimal cut-off values were calculated using a positive test based on receiver operating characteristics.Intrapancreatic Gd concentration after the injection of each contrast media was measured using laser ablation-inductively coupled plasma-mass spectrometry in a separate set of rats(4 diabetic rats, 4 controls for Gadofluorine P; 2, 2 for Gd-DOTA).RESULTS: The normalized SI and ER of the pancreas using Gd-DOTA were not significantly different between diabetic rats and controls. With Gadofluorine P, the values were significantly higher in the diabetic rats than in the control rats 30 min after injection(P < 0.05). The area under the receiver operating characteristic curve that differentiated diabetic rats from the control group was greater for Gadofluorine P than for Gd-DOTA(0.967 vs 0.667, P = 0.085). An increase in normalized SI 30 min after Gadofluorine P was correlated with a decrease in the mean number of islets(r 2 = 0.510, P = 0.014). Intra-pancreatic Gd was higher in rats with Gadofluorine P injection than Gd-DOTA injection(Gadofluorine P vs Gd-DOTA, 7.37 vs 0.00, P < 0.01). A significant difference in the concentration of intrapancreatic Gd was observed between the control and diabetic animals that were sacrificed 30 min after Gadofluorine P injection(control vs diabetic, 3.25 ng/g vs 10.55 ng/g, P < 0.05)CONCLUSION: In this STZ-induced diabetes rat model,Gadofluorine P-enhanced MRI of the pancreas showed high accuracy in the diagnosis of diabetes.

Analysis of Imperfect Acoustic Cloaking Resonances

We study the resonance phenomenon arising from imperfect acoustic cloaking in 2D based on a small perturbation of the transformation acoustics.It is shown that the resonant frequencies of imperfect cloaking appearing in the total scattering cross section converge to Dirichlet eigenvalues of the concealed region as a perturbation parameter approaches zero.This theory enables us to predict the location of the resonant frequencies of imperfect cloaking and to identify the corresponding resonance modes.

Aqueous extract of freeze-dried Protaetia brevitarsis larvae promotes osteogenesis by activating β-catenin signaling

Objective:To investigate the effect of an aqueous extract of Protaetia brevitarsis(AEPB)on osteogenesis using preosteoblast MC3T3-E1 cells and zebrafish larvae.Methods:Flow cytometric analysis was used to measure the cytotoxicy.Alkaline phosphatase activity was detetmined using p-nitrophenyl phosphate as a substrate.Calcium deposition was detected using alizarin red staining along with osteogenic marker expression in preosteoblast MC3T3E1 cells.In addition,vertebral formation in zebrafish larvae was detected using calcein staining and osteogenic gene expression.Results:AEPB highly promoted the expression of osteogenic markers including runt-related transcription factor 2,osterix,and alkaline phosphatase,along with elevated levels of mineralization in MC3T3-E1 cells.Moreover,AEPB accelerated vertebral formation in zebrafish larvae accompanied by upregulated expression of osteogenic genes.FH535,an inhibitor of Wnt/β-catenin,suppressed AEPB-induced osteogenic gene expression and vertebral formation,indicating that AEPB stimulates osteogenesis by activating the Wnt/β-catenin signaling pathway.Conclusions:AEPB stimulates osteoblast differentiation and bone formation by activatingβ-catenin.Therefore,AEPB is a promising material that induces osteogenesis,and is useful for the treatment of bone resorption diseases.

Suppression of the Resonant Scattering in Imperfect Acoustic Cloaking with a Lossy Medium in R^3

It has been realized that resonance frequencies of imperfect the transformation acoustics in R^2 are located near Dirichlet acoustic cloaking based on a small perturbation of eigenvalues of the cloaked region [Chin. Phys. Lett. 26 （2009） 014301; 29 （2012） 124301]. In this work, we study the performance of the three-dimensional approximate cloaking system based on the transformation acoustics and show that the cloaking effect may be deteriorated at zeroth order Neumann eigenvalues of the concealed region. In particular, transmitted fields into the concealed region can be extremely resonated at frequencies corresponding to the zeroth-order Neumann eigenvalues while scattered fields are suppressed well for any frequency. To enhance the cloaking effect at resonance frequencies, we introduce a lossy medium inside the cloaked region and show that the new proposal can reduce the intensity of transmitted fields significantly due to the lossy medium.

Toward Systems Understanding of Leaf Senescence： An Integrated Multi-Omics Perspective on Leaf Senescence Research

Leaf senescence is a complex but tightly regulated developmental process involving a coordinated sequence of multiple molecular events, which ultimately leads to death of the leaf. Efforts to understand the mechanistic principles underlying leaf senescence have been largely made by transcriptomic, proteomic, and metabolomic studies over the past decade. This review focuses on recent milestones in leaf senes- cence research obtained using multi-omics technologies, as well as future endeavors toward systems understanding of leaf senescence processes. In particular, we discuss recent advances in understanding molecular events during leaf senescence through genome-wide transcriptome analyses in Arabidopsis. We also describe comparative transcriptome analyses used to unveil the commonality and diversity of regulatory mechanisms governing leaf senescence in the plant kingdom. Finally, we provide current illustrations of epigenomic, proteomic, and metabolomic landscapes of leaf senescence. We envisage that integration of multi-omics leaf senescence data will enable us to address unresolved questions regarding leaf senescence, including determining the molecular principles that coordinate concurrent and ordered changes in biological events during leaf senescence.

Spindle-like FeySs/N-doped carbon nanohybrids for high-performance sodium ion battery anodes

Iron sulfides have bee n con sidered as one of the most promising can didates for sodium ion battery anode materials due to their high theoretical capacity and low cost. I n this work, spin dle-like Fe7S8 with n itroge rvdoped carb on (FeiS/N-C) nano hybrids are successfully syn thesized via a solvothermal method by sulfidation iron-based metal organic framework (FeMOF). As sodium ion battery an odes, FeySs/N-C nano hybrids exhibit high reversible capacity of 450.8 mAh g-1 at 200 mA·g^-1, and 406.7 mAh·g^-1 at 500 mA·g^-1 even after 500 cycles. They also show excellent rate properties and delivering the capacity of 327.8 mAh·g^-1 at a very high current density of 3.2 A·g^-1. These outstanding electrochemical performa nces can be attributed to the unique structure of Fe7S8/ N-C nan ohybrids. The nano scale dime nsion in their size can be ben eficial for facile ion and electro n tran sports. Furthermore, the stable n itroge n doped carb on frameworks can also improve electrical conductivity and relieve the problems related to volume expansion. X-ray absorption spectroscopy and X-ray photoelectron spectroscopy analyses have been performed to study reactions occurred in spindle-like FeySs/N-C nanohybrid electrode at both bulk and surface.

Flexible quantum dot light-emitting diodes for next-generation displays

In the future electronics,all device components will be connected wirelessly to displays that serve as information input and/or output ports.There is a growing demand of flexible and wearable displays,therefore,for information input/output of the nextgeneration consumer electronics.Among many kinds of light-emitting devices for these next-generation displays,quantum dot light-emitting diodes(QLEDs)exhibit unique advantages,such as wide color gamut,high color purity,high brightness with low turn-on voltage,and ultrathin form factor.Here,we review the recent progress on flexible QLEDs for the next-generation displays.First,the recent technological advances in device structure engineering,quantum-dot synthesis,and high-resolution full-color patterning are summarized.Then,the various device applications based on cutting-edge quantum dot technologies are described,including flexible white QLEDs,wearable QLEDs,and flexible transparent QLEDs.Finally,we showcase the integration of flexible QLEDs with wearable sensors,micro-controllers,and wireless communication units for the next-generation wearable electronics.

Materials and devices for flexible and stretchable photodetectors and light-emitting diodes

Recently,significant efforts have been directed at overcoming the limitations of conventional rigid optoelectronic devices,particularly their poor mechanical stability under bending,folding,and stretching deformations.One of major approaches for rendering optoelectronic devices mechanically deformable is to replace the conventional electronic/optoelectronic materials with functional nanomaterials or organic materials that are intrinsically flexible/stretchable.Further,advanced device designs and unconventional fabrication methods have also contributed to the development of soft optoelectronic devices.Accordingly,new devices such as bio-inspired curved image sensors,wearable light emitting devices,and deformable bio-integrated optoelectronic devices have been developed.In this review,recent progress in the development of soft optoelectronic materials and devices is outlined.First,various materials such as nanomaterials,organic materials,and their hybrids that are suitable for developing deformable photodetectors,are presented.Then,the nanomaterials and organic/polymeric materials that are applicable in deformable light-emitting diodes are described.Finally,representative system-level applications of flexible and stretchable photodetectors and light-emitting diodes are reviewed,and future prospects are discussed.

Iron sulfides with dopamine-derived carbon coating as superior performance anodes for sodium-ion batteries

High energy ball-milled iron sulfides with thin carb on layer coati ng(BM-FeS/C composites)were prepared by the simple and econo mical process.Ball-milled process,followed by carb on coati ng,reduced the particle size and increased the electrical con ductivity.Whe n employed as sodium-ion battery ano des,BM?F eS/C composites showed extremely high electrochemical performa nee with reversible specific capacity of 589.8 mAh·g^-1 after 100 cycles at a current density of 100 mA·g^-1.They also exhibited superior rate capabilities of 375.9 mAh·g^-1 even at 3.2 Ag^1 and 423.6 mAh·g^-1 at 1.5 Ag_1.X-ray absorptio n near edge structure an alysis con firmed the electrochemical pathway for con version reaction of BM-FeS/C composites.

Method of characteristics and first integrals for systems of quasi-linear partial differential equations of first order

Given a set of independent vector fields on a smooth manifold, we discuss how to find a function whose zero-level set is invariant under the flows of the vector fields. As an application, we study the solvability of overdetermined partial differential equations: Given a system of quasi-linear PDEs of first order for one unknown function we find a necessary and sufficient condition for the existence of solutions in terms of the second jet of the coefficients. This generalizes to certain quasi-linear systems of first order for several unknown functions.

Nanoscale Materials and Deformable Device Designs for Bioinspired and Biointegrated Electronics

Electronic devices whose structural and functional features are inspired by living creatures have unique performance and unconventional features that are not found in conventional electronic devices.In addition to such bioinspired electronics,with the rise of new fields such as personalized healthcare,mobile electronics,and big-data analysis,biointegrated electronic devices that can collect biomedical information from the human body through various biosensors and deliver appropriate therapeutic feedback stimulations in real time on the spot where immediate treatment is needed have become important.Because body parts and internal organs of living creatures,including humans,have curvilinear shapes and comprise mechanically soft tissues,such bioinspired and biointegrated electronic devices are required to match the soft and deformable features of biological tissues.Such soft and deformable features of electronic devices can be achieved by employing flexible and stretchable materials and unconventional device design techniques.These soft materials and deformable device designs dissipate stress originating from mechanical deformation of the device and thus retard crack generation and/or propagation in the device.Recently,technologies for nanoscale materials have shown a significant level of progress on their material performance and processing technologies.The nanoscale dimension of the electronic materials could achieve extremely small flexural rigidity in comparison to the bulk state of the same materials.Furthermore,techniques to form a well-percolated network of nanomaterials in the elastomeric matrix and to build a pathway for the facile electron and hole transport inside the polymer have induced dramatic performance advances of soft electronic materials,which led to nanocomposites that can accomplish both high mechanical deformability and high electrical performance at the same time.In addition,deformable device designs such as buckled structures and serpentine designs enhance the flexibility and stretchability of the device further.Because of their soft and deformable nature,bioinspired and biointegrated electronic devices could achieve device structures inspired by living creatures and make conformal contact to the target tissue for high-quality measurement of biological signals and real-time feedback treatments.Herein,we introduce recent advances in nanoscale materials and deformable device designs for bioinspired and biointegrated electronics.First,materials with various geometries(e.g.,one-dimensional(1D)nanowires and nanotubes,two-dimensional(2D)nanomembranes and nanoflakes,and three-dimensional(3D)networks of nanomaterials in polymers)are reviewed in terms of their deformable nature.Then,the representative device design strategies required for achieving a soft and deformable form factor(e.g.,buckling method,serpentine design,and kirigami technique)are reviewed.Examples of such state-of-the-art electronic devices are then presented,after which representative system-level applications,including electronic eyes,electronic skin,an electronic ear,wearable electronics,and implantable electronics,are described.Finally,we present a brief future outlook for the field of bioinspired and biointegrated electronics.

How Do Phytochromes Transmit the Light Quality Information to the Circadian Clock in Arabidopsis？

Dear Editor, Plants use light as an environmental signal to coor- dinate diverse physiological and developmental processes, thereby increasing their fitness. Light quality, quantity, and photoperiod change periodically under natural condi- tions of daily and seasonal cycles. Plants have developed a circadian clock to respond to these predictable, periodic environmental changes, providing plants with the ability to anticipate daily and seasonal environmental changes.

Erratum to: Materials and devices for flexible and stretchable photodetectors and light-emitting diodes

Erratum to Nano Research 2021,14(9):2919-2937 https://doi.org/10.1007/s 12274-021-3447-3 The figure caption of Figure 1,instead of Figure 1 Schematic illustration of various nanomaterials and organic materials used in flexible/stretchable photodetectors and light-emitting diodes,and some representative applications.

Wearable EEG electronics for a Brain–AI Closed-Loop System to enhance autonomous machine decision-making

Human nonverbal communication tools are very ambiguous and difficult to transfer to machines or artificial intelligence(AI).If the AI understands the mental state behind a user’s decision,it can learn more appropriate decisions even in unclear situations.We introduce the Brain-AI Closed-Loop System(BACLoS),a wireless interaction platform that enables human brain wave analysis and transfers results to AI to verify and enhance AI decision-making.We developed a wireless earbud-like electroencephalography(EEG)measurement device,combined with tattoo-like electrodes and connectors,which enables continuous recording of high-quality EEG signals,especially the error-related potential(ErrP).The sensor measures the ErrP signals,which reflects the human cognitive consequences of an unpredicted machine response.The AI corrects or reinforces decisions depending on the presence or absence of the ErrP signals,which is determined by deep learning classification of the received EEG data.We demonstrate the BACLoS for AIbased machines,including autonomous driving vehicles,maze solvers,and assistant interfaces.

Structural basis of DNA binding by the NAC transcription factor ORE1,a master regulator of plant senescence

Plants use sophisticated mechanisms of gene expression to control senescence in response to environmental stress or aging.ORE1(Arabidopsis thaliana NAC092)is a master regulator of senescence that belongs to the plant-specific NAC transcription factor protein family.ORE1 has been reported to bind to multiple DNA targets to orchestrate leaf senescence,yet the mechanistic basis for recognition of the cognate gene sequence remains unclear.Here,we report the crystal structure of the ORE1-NAC domain alone and its DNA-binding form.The structure of DNA-bound ORE1-NAC revealed the molecular basis for nucleobase recognition and phosphate backbone interactions.We showthat local versatility in the DNA-binding site,in combination with domain flexibility of the ORE-NAC homodimer,is crucial for the maintenance of binding to intrinsically flexible DNA.Our results provide a platformfor understanding other plant-specific NAC protein-DNA interactions as well as insight into the structural basis of NAC regulators in plants of agronomic and scientific importance.