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In‐memory computing and sensing can break through the limit of the traditional Von Neumann architecture where information storing and computing units are separated. Recently the topographic creation of a ferroelectric domain wall in separation of two antiparallel domains in LiNbO3 single‐crystal films integrated with the Si substrate has been the focus of such research. Here, the additional freedom of the light stimulus is reported to modulate the domain wall current significantly, enabling applications in nonvolatile domain wall memory, photodetector, and image recognition processor. These measurements shows the fantastic photosensitivity of 2D domain walls where the photocurrent varies nonlinearly against the accumulative pulse number. With this observation, an associated learning model is constructed to stimulate neuromorphic computing (with a recognition accuracy of 90%) using an artificial neuromorphic network of domain walls. The research promotes the multifold development of artificial intelligence using domain‐wall nanodevices sensitive to both optical and electrical stimulus. [ABSTRACT FROM AUTHOR]

Compared to hot roll and explosive bonding, there are relatively few studies on warm/cold roll bonding under low temperature conditions. In this article, the warm/cold roll bonding simulation experiment is conducted to research the deformation, interface bonding rate, microstructure, element diffusion behavior, metallographic structure, and phase of carbon steel/stainless steel. The results show that the plastic deformation remains consistent below 400 °C but exhibits temperature sensitivity above 400 °C. The lower strain rate can increase the bonding rate, while insulation treatment may reduce the bonding rate. The formation of cracks is inhibited at 25 °C and 45% reduction rate due to the challenge of cracking the surface oxide film. Temperature significantly affects bonding, with improved performance observed above 600 °C. Uneven element distribution of bonding area may be related to the precipitated compounds, while insulation treatment increases the mutual diffusion ability of elements. The increase in temperature leads to an increase in pearlite, a decrease in ferrite, and decarburization occurs within the carbon steel matrix. The carbon elements diffuse from carbon steel to the surface of stainless steel. The increase in temperature increases the content of surface compounds. [ABSTRACT FROM AUTHOR]

Cocatalysts play a key role in enhancing activity of photoelectrodes while the study of their interaction remains a challenge. Here, we decoupled the relationship between oxygen evolution reaction (OER) performance and photoelectrochemical (PEC) water oxidation performance by modifying an identical BiVO4 with different cobalt‐based OER catalysts including Co, CoO, Co3O4, and Co4N. The electrochemical OER activities of these cobalt specimens were quite similar. Their anodic photocurrent density followed an order of: Co4N>Co>Co3O4>CoO after loading on the BiVO4 electrode. The kinetics process and energy band diagram were analyzed, revealing that the interface between different cobalt specimens and BiVO4 electrode influenced the charge recombination and transfer. Accordingly, we propose a corresponding structural model, which shows that the cocatalysts consist of inner part for interface modulation and the outer layer for catalysis. The present work reveals the vital role of contact interface between cocatalysts and semiconductors, and more attention should be paid when selecting the cocatalysts. [ABSTRACT FROM AUTHOR]

Electrochemical reduction of CO2 and nitrate offers a promising avenue to produce valuable chemicals through the using of greenhouse gas and nitrogen‐containing wastewater. However, the generally proposed reaction pathway of concurrent CO2 and nitrate reduction for urea synthesis requires the catalysts to be both efficient in both CO2 and nitrate reduction, thus narrowing the selection range of suitable catalysts. Herein, we demonstrate a distinct mechanism in urea synthesis, a tandem NO3− and CO2 reduction, in which the surface amino species generated by nitrate reduction play the role to capture free CO2 and subsequent initiate its activation. When using the TiO2 electrocatalyst derived from MIL‐125‐NH2, it intrinsically exhibits low activity in aqueous CO2 reduction, however, in the presence of both nitrate and CO2, this catalyst achieves an excellent urea yield rate of 43.37 mmol ⋅ g−1 ⋅ h−1 and a Faradaic efficiency of 48.88 % at −0.9 V vs. RHE in a flow cell. Even at a low CO2 level of 15 %, the Faradaic efficiency of urea synthesis remains robust at 42.33 %. The tandem reduction procedure was further confirmed by in situ spectroscopies and theoretical calculations. This research provides new insights into the selection and design of electrocatalysts for urea synthesis. [ABSTRACT FROM AUTHOR]

Three‐way concept analysis is an important tool for information processing, and rule acquisition is one of the research hotspots of three‐way concept analysis. However, compared with three‐way concept lattices, three‐way semi‐concept lattices have three‐way operators with weaker constraints, which can generate more concepts. In this article, the problem of rule acquisition for three‐way semi‐concept lattices is discussed in general. The authors construct the finer relation of three‐way semi‐concept lattices, and propose a method of rule acquisition for three‐way semi‐concept lattices. The authors also discuss the set of decision rules and the relationships of decision rules among object‐induced three‐way semi‐concept lattices, object‐induced three‐way concept lattices, classical concept lattices and semi‐concept lattices. Finally, examples are provided to illustrate the validity of our conclusions. [ABSTRACT FROM AUTHOR]

Understanding the nature of parental melts for pyroxenite veins in supra‐subduction zone (SSZ) ophiolites provides vibrant constraints on melt infiltration processes operating in subduction zones. The Zedang ophiolitic massif in the eastern Yarlung–Zangbo suture zone in Tibet consists of mantle peridotites and a crustal section of gabbro, diabase, and basalt. Veins of two pyroxenite varieties cut the southern part of the Zedang massif. These pyroxenite rocks have different geochemical characteristics, where the first variety (type‐I) has relatively higher contents of SiO2 (51.82–53.08 wt%), MgO (20.08–23.23 wt%), and ΣPGE (3.42–13.97 ppb), and lower Al2O3 (1.59–2.28 wt%) and ΣREE (1.63–2.94 ppm). The second pyroxenite variety (type‐II) is characterized by SiO2 (45.44–49.61 wt%), MgO (16.68–19.78 wt%), Al2O3 (4.24–8.77 wt%), ΣPGE (14.46–322.06 ppb), and ΣREE (5.82–7.44 ppm). Pyroxenite type‐I shows N‐MORB‐like chondrite‐normalized REE patterns. Zircon U‐Pb ages of pyroxenite type‐I (194 ± 10 Ma), associated ophiolitic gabbro (135.3 ± 2.0 Ma), and plagiogranite (124.2 ± 2.3 Ma) evidently imply episodic evolution of the Zedang ophiolites. The mineralogical and geochemical characteristics of the investigated pyroxenites can be explained by subduction‐initiated hydrous melting of metasomatized sub‐arc mantle, later overprinted by sub‐slab mantle melting triggered by upwelling asthenosphere during the Jurassic–Early Cretaceous times. The geochemical variations in pyroxenite vein composition, coupled with age differences amongst the other ophiolite units, may correspond to intermittent emplacement of pyroxenite dikes and isotropic gabbroic intrusions where the geodynamic setting progressed from arc maturation and slab rollback to slab tearing and delamination. [ABSTRACT FROM AUTHOR]

Summary: N6‐methyladenosine (m6A) is the most prevalent internal modification present in mRNAs, and is considered to participate in a range of developmental and biological processes. Drought response is highly regulated at the genomic, transcriptional and post‐transcriptional levels. However, the biological function and regulatory mechanism of m6A modification in the drought stress response is still poorly understood. We generated a transcriptome‐wide m6A map using drought‐resistant and drought‐sensitive varieties of cotton under different water deficient conditions to uncover patterns of m6A methylation in cotton response to drought stress. The results reveal that m6A represents a common modification and exhibit dramatic changes in distribution during drought stress. More 5'UTR m6A was deposited in the drought‐resistant variety and was associated with a positive effect on drought resistance by regulating mRNA abundance. Interestingly, we observed that increased m6A abundance was associated with increased mRNA abundance under drought, contributing to drought resistance, and vice versa. The demethylase GhALKBH10B was found to decrease m6A levels, facilitating the mRNA decay of ABA signal‐related genes (GhZEP, GhNCED4 and GhPP2CA) and Ca2+ signal‐related genes (GhECA1, GhCNGC4, GhANN1 and GhCML13), and mutation of GhALKBH10B enhanced drought resistance at seedling stage in cotton. Virus‐induced gene silencing (VIGS) of two Ca2+‐related genes, GhECA1 and GhCNGC4, reduced drought resistance with the decreased m6A enrichment on silenced genes in cotton. Collectively, we reveal a novel mechanism of post‐transcriptional modification involved in affecting drought response in cotton, by mediating m6A methylation on targeted transcripts in the ABA and Ca2+ signalling transduction pathways. [ABSTRACT FROM AUTHOR]

Summary: This article addresses the distributed adaptive synchronization tracking control problem for multiple flying‐wing UAVs with predefined accuracy and unknown input nonlinearities. Considering that the multiple flying‐wing unmanned aerial vehicles (UAVs) system is a large‐scale nonlinear and strongly coupled system, the control schemes in existing literature which only consider longitudinal, lateral or attitude control may not be applicable in practical engineering. Thus, a full‐state flying‐wing UAV model containing both translational and rotational motions is established, whose dynamics are six‐degree‐of‐freedom with twelve‐state‐variables. Furthermore, to handle the problem that the prior knowledge of the actuator nonlinearities of multi‐UAV system are difficult to obtain, a more general input nonlinear model is established and the adaptive boundary estimation technique is developed. Finally, a performance‐oriented controller is proposed by incorporating a series of smooth functions into adaptive neural control design and Lyapunov analysis. Theoretical analysis and simulation results show that the presented control scheme can guarantee the satisfactory transient tracking error performance, and the tracking error converges to a user‐defined interval ultimately. [ABSTRACT FROM AUTHOR]

The incidence of respiratory diseases such as chronic obstructive pulmonary disease and pulmonary cancer is growing significantly around the world, making pulmonary disease one of the leading causes of mortality. However, the development of effective therapeutics for pulmonary diseases has been hindered by the lack of human‐mimetic physiological models that reliably emulate patient responses. Recent advances in technology and cell culture have led to the development of organoids and organ‐on‐a‐chip models that allow us to recapitulate the structure, cellular organization, and organ‐level responses of the target tissue in vitro. Here, we review the advances and milestones of lung organoid and lung‐on‐a‐chip models in the past decade and highlight their applications in mimicking pulmonary system development, physiology, disease, and regeneration. In addition, we discuss the ongoing challenges and the future prospects of integrating lung organoids and lung‐on‐a‐chip models to overcome current limitations and to enhance their physiological relevance. These human‐centric models are likely to provide important insights into pulmonary physiology and pathophysiology for drug discovery that complement and potentially replace traditional animal models. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) performance of WO3 photoanodes for water splitting is heavily influenced by the orientation of crystal facets. In this work, mono‐particle‐layer electrodes, assembled by particulate WO3 square plates with highly uniform alignment along the (002) facet, improved PEC water oxidation kinetics and stability. Photo‐deposition of Au along the cracks formed on the surface of the plates, which are the edges of {110} facets, was found to further enhance electron collection efficiency. Combination of these two strategies allowed the facet‐engineered WO3 electrode to produce significantly higher efficiencies in charge separation and transfer than the electrode prepared without facet orientation. This work has provided a facile route for fabricating a structurally designed WO3 photoelectrode, which is also applicable to other regularly shaped semiconductor photocatalysts with anisotropic charge migration. [ABSTRACT FROM AUTHOR]

In recent years, research has begun to touch upon the associations between the natural environment and individuals' subjective wellbeing; however, whether such associations would vary among different groups of people remains under‐studied. Using four waves (2010–2013) of data from the Chinese General Social Survey, we investigate the group‐specific correlation between environment—specifically, greenspace exposure—and individuals' happiness in contemporary urban China. For this study, the normalized difference vegetation index at the county level is a proxy for greenspace exposure. The results from the ordered logit model indicate that county‐level green vegetation is associated with individuals' happiness level, but such effects vary with a household's relative deprivation. While greenspace exposure is positively associated with happiness among individuals from less deprived families, it is negatively associated with happiness among those from deprived households. These findings contribute to the body of knowledge of the heterogeneous effect of greenspace on residents' subjective well‐being. [ABSTRACT FROM AUTHOR]

This paper is devoted to the cooperative tracking control of multiple unmanned aerial vehicles with unknown faults. Considering the practical case that the unmanned aerial vehicles suffer from strong nonlinearities, external disturbances, actuator, and sensor faults, this brief investigates the distributed adaptive fault tolerant scheme for multi‐unmanned aerial vehicle system within model predictive control framework. Firstly, for preparation to the fault occurrence case, the baseline model predictive control scheme is designed under fault‐free case. Then considering the fault occurrence, a fault detection strategy is proposed by means of the moving horizon estimation and linearly parameterized approximation for actuator and sensor faults, respectively. Thereby with the characterized fault information, the fault tolerant model predictive control scheme is constructed by using an adaptive updating mechanism to compensate for actuator and sensor faults simultaneously. Finally, simulations well demonstrate the effectiveness of proposed control scheme. [ABSTRACT FROM AUTHOR]

Summary: This article studies the adaptive model predictive control with extended state observers (ESO) to deal with multiple unmanned aerial vehicles formation flight in presence of external disturbances and system uncertainties. Specifically, to deal with the mismatch of predictive model caused by external disturbances and system uncertainties, ESOs are introduced to estimate the lumped disturbances, where the ultimately bounded property of observer system can be guaranteed by using the Lyapunov stability theorem. With these observations, the distributed adaptive model predictive controller is designed to achieve trajectory tracking and disturbance rejection simultaneously for multiple unmanned aerial vehicles, as well as taking the state and input saturation into account. Moreover, the stability of proposed model predictive controller is analyzed. Finally, the simulation examples are provided to illustrate the validity of the proposed control scheme. [ABSTRACT FROM AUTHOR]

To support historians in their work, we need to understand their work‐related needs and propose what is required to support those needs. Although the quantity of digitized historical documents available is increasing, historians' ways of working with the digital documents have not been widely studied, particularly in authentic work settings. To better support the historians' reasoning processes, we investigate history researchers' work tasks as the context of information interaction and examine their cognitive access points into information. The analysis is based on a longitudinal observational research and interviews in a task‐based research setting. Based on these findings in the historians' cognitive space, we build bridges into the document space. By studying the information interactions in real task contexts, we facilitate the provision of task‐specific handles into documents that can be used in designing digital research tools for historians. [ABSTRACT FROM AUTHOR]

A direct aerobic oxidative dehydrogenative coupling reaction of glycine derivatives with electron‐rich arenes has been accomplished via the synergistic combination of organic‐dye mediated photoredox catalysis and Lewis acid catalysis. This process exhibits good tolerance of functional groups and provides rapid synthesis of arylglycine derivatives at room temperature under an air atmosphere. Moreover, this protocol could be performed on a 10 mmol scale, without obvious reduction of the yield. [ABSTRACT FROM AUTHOR]

Drug screening with simplified 2D cell culture and relevant animal testing fail to predict clinical outcomes. With the rising cost of drug development, predictive 3D tissue models with human cells are in urgent demand. Establishing vascular perfusion of 3D tissues has always been a challenge, but it is necessary to mimic drug transport and to capture complex interorgan crosstalk. Here, a versatile multiwell plate is presented empowered by built-in microfabricated vascular scaffolds that define the vascular space and support self-assembly of various parenchymal tissues. In this configuration, assembly and organ-specific function of a metabolically active liver, a free-contracting cardiac muscle, and a metastatic solid tumor are demonstrated, tracking organ function using noninvasive analysis techniques. By linking the 3D tumor and the liver tissue in series, it is demonstrated that the presence of liver tissue is crucial to correctly reveal the efficacy of a chemotherapeutic drug, Tegafur. Furthermore, the complete cancer metastasis cascade is demonstrated across multiple organs, where cancer cells escaping from the solid tumor can invade a distant liver tissue connected through a continuous vascular interface. This combinatory use of microfabricated scaffold onto a standard cell culturing platform can offer important insights into the mechanics of complex interorgan biological events. [ABSTRACT FROM AUTHOR]

In this study, it is shown that the chemical exchange saturation transfer (CEST) method for hydroxyl protons can be used to detect changes in glycosaminoglycan (GAG) concentration in the intervertebral disc. The method, termed gagCEST, was demonstrated ex vivo by correlating the CEST effect with the fixed charge density (FCD) of the nucleus pulposus (NP), as well as by correlating tissue CEST images with their corresponding 23Na images. Incubation of five NP samples with trypsin produced samples with varying GAG content ( n = 19). A good correlation was found between the -OH CEST effect and FCD, as well as with the N-acetyl signal amplitude. gagCEST images in vitro further illustrated the amount of detail obtainable from this contrast mechanism when compared with conventional imaging. The large concentration of GAG and the relatively long T1 of water in NP make the method sensitive, in particular, for the assessment of GAG depletion in this tissue. It is the loss of GAG in NP that indicates the early stage of disc degeneration. Copyright © 2011 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

This study integrated paper‐based microfluidic device on a milk carton for a rapid milk quality check. The microfluidic device was printed on the outer surface of milk carton using commercial wax printer. The testing process is fully automatic, after apply one drop of milk on the loading point, milk was driven by capillary force in the porous paper fiber in wax‐defined microchannels to reach the preload reactants for chromogenic reaction. The proposed integration method provides a simple, low cost and rapid onsite milk quality check technique for milk consumers, and also have wide potential applications in food industry. Practical applications: Microfluidics has been widely used in the chemical and biological field for analysis or synthesis, in this research, the microfluidic devices were integrated on the outer surface of a milk carton for a rapid and low‐cost milk quality test, and the test result could be easily read using mobile phone app. The proposed research is of significant application prospect in food industry for rapid and onsite food quality test using the microfluidic devices integrated on paper packaging. The fabrication method of the microfluidic devices proposed in this research using wax printing is also low cost and nontoxic, and could be easily integrated with the current paper packaging production line. [ABSTRACT FROM AUTHOR]

In article 1703524, Milica Radisic, Boyang Zhang, and co‐workers present a user‐friendly 96‐well plate platform (InVADE, Integrated Vasculature for Assessing Dynamic Events) that utilizes a single vascularized scaffold to replicate in vivo like drug transfer and cell trafficking between multiple organs. Offering highly reproducible in vivo simulation of complex multi‐organ biological events, this platform is promising for drug evaluation. [ABSTRACT FROM AUTHOR]