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Detection of vector magnetic fields at nanoscale dimensions is critical in applications ranging from basic material science and fundamental physics to information storage and medical diagnostics. So far, nanoscale vector magnetic field sensing is achieved solely by exploiting a single nitrogen‐vacancy (NV) center in a diamond, by evaluating the Zeeman splitting of NV spin qubits by using the technique of an optically‐detected magnetic resonance. This protocol requires a complex optical setup and expensive detection systems to detect the photoluminescence light, which may limit miniaturization and scalability. Here, a simple approach with all‐electric operation to sensing a vector magnetic field at 200 × 200 nm2 dimensions is experimentally demonstrated, by monitoring a stochastic nanomagnet's transition probability from a metastable state, excited by a driving current due to spin‐orbit torque, to a settled state. [ABSTRACT FROM AUTHOR]

Hydrogen peroxide (H2O2) is an essential and versatile oxidant. The photocatalytic production of H2O2 is a promising alternative to the conventional anthraquinone oxidation process. In this work, BiOBr nanosheets with oxygen vacancies (OVs) were successfully synthesized by a solvothermal method in the presence of mannitol. The character of the nanosheets shortened the diffuse length of charge carriers, which is beneficial for the charge separation. The introduction of OVs enhanced the visible light absorption and also improved the carrier separation. Furthermore, OVs enhanced the activation of O2 molecules and facilitated the generation of ˙O2−. As a result, the products exhibited good performance in photocatalytic H2O2 production. After introducing HCOOH, the yield of H2O2 was further enhanced by a factor of 50, from 3 μmol h−1 to 150 μmol h−1. This work provides a reference to design high performance photocatalysts for H2O2 production through defect engineering. [ABSTRACT FROM AUTHOR]

In a three-coil wireless power transfer system with relay coils, the transmission efficiency and output power of the system decreases with changes in the adjacent coupling coefficients. Controlling the power of three-coil wireless power transfer systems is also a significant challenge. To solve these issues, a three-coil wireless power transfer system based on parity–time symmetry is proposed in this paper. First, a three-coil parity–time wireless power transfer system was modeled based on a circuit model. Then, the transmission and gain characteristics of the three-coil parity–time wireless power transfer system were analyzed. It was found that when the system is in a parity–time-exact region, it can maintain a constant transmission efficiency and output power, and its output power is independent of the coupling coefficient. In addition, based on the output characteristics of the three-coil parity–time wireless power transfer system, a power control method and a working range detection method were proposed to attain a constant power output. Finally, a three-coil parity–time wireless power transfer system was experimentally tested. [ABSTRACT FROM AUTHOR]

Production of p-xylene (PX) via a broad biomass-derived furan cycloaddition has received incremental interest because of its renewable character. To date, the [4 + 2] cycloaddition reaction of furan derivatives with acrylic acid (AA) to synthesize PX has been achieved mainly by thermo-catalysis, but the stern reaction conditions usually lead to high energy costs. Herein, we report a copper-mediated decarboxylative cycloaddition within PW@HKUST-1 under visible-light irradiation to realize rapid synthesis of PX with 92.6% yield in 3 h under atmospheric pressure. Preliminary mechanistic studies reveal a radical decarboxylation process via ligand-to-metal charge transfer (LMCT) that initiates the [4 + 2] cycloaddition under visible-light irradiation. This work suggests that photoexcited [4 + 2] cycloaddition could be a cost-effective strategy for the synthesis of biomass-derived PX. [ABSTRACT FROM AUTHOR]

Converting extensive sugars into value‐added 2,5‐furandicarboxylic acid (FDCA) has been considered to be a promising approach to developing sustainable substitutes for chemicals from fossil resources. The complicated conversion processes involved multiple cascade reactions and intermediates, which made the design of efficient multifunction catalysts challenging. Herein, we developed a catalyst by introducing phosphotungstic acid (PW) and Co sites into the UiO‐66, which achieved a one‐pot cascade conversion of fructose‐to‐FDCA with high conversion (>99 %) and yield (94.6 %) based on the controllable Lewis/Brønsted acid sites and redox sites. Controlled experiments and detailed characterizations show that the multifunctional PW/UiO(Zr, Co) catalysts successfully affords the direct synthesis of FDCA from fructose via dehydration and selective oxidation in the one‐pot reaction. Additionally, the MOF catalysts could also efficiently convert various sugars into FDCA, which has broad application prospects. This study provides new strategies for designing multifunctional catalysts to achieve efficient production of FDCA from biomass in the one‐pot reaction. [ABSTRACT FROM AUTHOR]

As one of the most commonly bulky chemicals, chlorine is conventionally manufactured by electrolysis of NaCl solution in the chlor–alkali process, which requires a huge supply of electrical energy. The photocatalytic route to produce chlorine by using solar energy and NaCl solution offers a promising strategy to reduce energy consumption and bring economic benefits. Herein, it was found that the introduction of CO2 would enhance the productivity of Cl2 from 8.24 μmol⋅h−1 to 39.6 μmol⋅h−1 in NaCl solution over BiOCl. Experimental studies reveal that the CO2 species (CO32−) entered into the crystal texture of BiOCl and the interlayer space between [Bi2O2]2+ slabs were increased and distorted, accelerating the cycle of Cl species. Besides, the cycle of carbonate species also existed and accelerated the reaction efficiency of Cl− oxidation to Cl2. This work provides a new feasible method of using abundant CO2 resources to accelerate the process of chlorine production via photocatalysis. [ABSTRACT FROM AUTHOR]

Abiotic stress is the adverse effect of any abiotic factor on a plant in a given environment, impacting plants' growth and development. These stress factors, such as drought, salinity, and extreme temperatures, are often interrelated or in conjunction with each other. Plants have evolved mechanisms to sense these environmental challenges and make adjustments to their growth in order to survive and reproduce. In this review, we summarized recent studies on plant stress sensing and its regulatory mechanism, emphasizing signal transduction and regulation at multiple levels. Then we presented several strategies to improve plant growth under stress based on current progress. Finally, we discussed the implications of research on plant response to abiotic stresses for high-yielding crops and agricultural sustainability. Studying stress signaling and regulation is critical to understand abiotic stress responses in plants to generate stress-resistant crops and improve agricultural sustainability. [ABSTRACT FROM AUTHOR]

The inclusion criteria of patients in this study were inconsistent especially in distinguishing Fuchs’ uveitis and herpetic uveitis from Posner-Schlossman syndrome, indicating well-defined inclusion criteria were needed. CMV anterior uveitis and Posner-Schlossman syndrome may not be the same disease, CMV may only act as a triggering factor for Posner-Schlossman syndrome, and the clinical manifestations of mild anterior segment inflammation were mainly caused by inflammatory reactions mediated by autoimmune factors. Although the antiviral medication was important in the treatment of Posner-Schlossman syndrome, the role of other treatment methods especially topical steroids should not be ignored. [ABSTRACT FROM AUTHOR]

The construction of aromatic skeleton structures by the Diels–Alder reaction is a synthetic route to obtain substitutes for petrochemical products using biomass as a raw material. In this work, a class of SiW@MIL-100(Fe)-n (n = 1–4) catalysts containing silicotungstic acid (SiW) encaged in MIL-100(Fe) was synthesized for the mimic synthesis of p-xylene (PX). SiW@MIL-100(Fe)-3 was applied to catalyze the reaction of 2,5-dimethylfuran and acrylic acid (AA) to give aromatic products (yield 94%, PX yield = 80.1%) at 140 °C under ambient pressure. The synergistic effect between the metal centers and Lewis/Brønsted acid was increased due to the confinement effect in the cage of MIL-100(Fe). The Fe(III) sites catalyzed the decarboxylation of AA via a free radical process, avoiding the formation of the 2,5-dimethylbenzoic acid intermediate. Two types of acid sites along with the reactants as well as the reversibly adsorbed water promoted the formation of hydrogen bonds with protons from SiW, which accelerated the dehydration reaction. This strategy provides a route for the construction of aromatic skeletons from biomass derivatives by MOF-based solid acid catalysts. [ABSTRACT FROM AUTHOR]

Let b \geq 2 be an integer and S be a finite non-empty set of primes not containing divisors of b. For any non-dense set A \subseteq [0,1) which is invariant under \times b operation, we prove the finiteness of rational numbers in A whose denominators can only be divided by primes in S. A quantitative result on the largest prime divisors of the denominators of rational numbers in A is also obtained. [ABSTRACT FROM AUTHOR]

Potentiostatic anodization was developed to synthesize copper oxide/copper (CuxO/Cu, x=1,2) electrode with nano structure for sensitive non‐enzymatic glucose detection. At a catalytic potential of 0.55 V, the CuO/Cu electrode presented a high sensitivity of 2954.38 μA mM−1 cm−2 to glucose and a linear range of 0.1 mM to 1.3 mM. The response time is less than 3 s with addition of 0.1 mM glucose. The CuO/Cu electrode above was anodized in 1M KOH solution at −100 mV and the morphology was compact nanoparticles and sparsely dispersed nanosheets, which enlarged the surface area and provided abundant electrocatalytic active sites. Compared the sensing property of electrodes with different morphologies, it indicated that nanostructure was significant to the efficient glucose catalytic oxidation process and it could be regulated by changing the potential and electrolyte concentration during anodization. [ABSTRACT FROM AUTHOR]

The conductivity and corrosion performance of metallic bipolar plates were crucial to the development of the proton exchange membrane fuel cell (PEMFC). In this study, polypyrrole (PPy) coatings doped with titanium nitride nanoparticles (TiN NPs) were deposited on 304 stainless steel (304SS) by constant potential polymerization. To improve dispersion and form a negative charge surface, TiN NPs were modified by anionic surfactants such as sodium dodecyl diphenyl ether disulfate (MADS). Through comparing potentiodynamic curves of the composite coatings in the simulated cathodic environment of PEMFC, the PPy‐0.1 TiN (0.1 g/L) coating presented a more positive corrosion potential (Ecorr = 293 mVAg/AgCl) and a lower corrosion current (Icorr = 0.841 μA cm−2). Furthermore, PPy‐0.1 TiN exhibited more stable corrosion resistance during long‐term immersion. Interfacial contact resistance (ICR) testing demonstrated that the addition of TiN NPs improved conductivity compared to a PPy coating. The results indicated that the PPy‐TiN‐coated 304SS could be used as a kind of promising bipolar plate material. [ABSTRACT FROM AUTHOR]

Plants absorb nitrogen from the soil using ammonium transporters (AMTs). Plants can precisely regulate AMT1;3 levels using sophisticated regulatory systems, ensuring adequate nitrogen uptake without hazardous ammonium production. Here, we demonstrated that ubiquitylation can contribute to AMT1;3 degradation under high ammonium stress. Using the ubiquitin site mutant AMT1;3K75R,K233R-EGFP, we demonstrated that the loss of ubiquitination affects the dynamic characteristics of AMT1;3 proteins on the plasma membrane and markedly inhibits the endocytosis of AMT1;3 proteins under high ammonium stress. AMT1;3K75R,K233R-EGFP plants also showed inhibition of protein degradation that targets the vesicular pathway after being exposed to high levels of ammonium. Our findings showed that the dynamic properties, endocytosis, and vesicle trafficking pathways of AMT1;3 proteins are altered in AMT1;3K75R,K233R-EGFP under high ammonium conditions. [ABSTRACT FROM AUTHOR]

Analog arithmetic operations are the most fundamental mathematical operations used in image and signal processing as well as artificial intelligence (AI). In‐memory computing (IMC) offers a high performance and energy‐efficient computing paradigm. To date, in‐memory analog arithmetic operations with emerging nonvolatile devices are usually implemented using discrete components, which limits the scalability and blocks large scale integration. Here, a prototypical implementation of in‐memory analog arithmetic operations (summation, subtraction and multiplication) is experimentally demonstrated, based on in‐memory electrical current sensing units using spin‐orbit torque (SOT) devices. The proposed structures for analog arithmetic operations are smaller than the state‐of‐the‐art complementary metal oxide semiconductor (CMOS) counterparts by several orders of magnitude. Moreover, data to be processed and computing results can be locally stored, or the analog computing can be done in the nonvolatile SOT devices, which are exploited to experimentally implement the image edge detection and signal amplitude modulation with a simple structure. Furthermore, an artificial neural network (ANN) with SOT devices based synapses is constructed to realize pattern recognition with high accuracy of ≈95%. [ABSTRACT FROM AUTHOR]

Detecting a three-dimensional (3D) magnetic field by a compact and simple structure or device has always been a challenging work. The recent discovery of 3D magnetic field sensing through the single spin–orbit torque device consisting of the Ta/CoFeB/MgO heterostructure, based on the domain wall motion, offers a revolutionary way to tackle this problem. Here, we demonstrate a 3D magnetic field sensor based on the W/CoFeB/MgO heterostructure via domain nucleation dominated magnetization reversal. In such a heterostructure, the in-plane (IP) and out-of-plane (OOP) magnetic field components drive the grains reversal with different manners, enabling the distinguishment of the contributions from IP and OOP components. The linear modulations of anomalous Hall resistance by x, y, and z components of magnetic fields have been obtained, respectively, with the same linear range of −20 to +20 Oe for each component. Typically, a higher linearity is realized in this work compared with the previous domain wall motion based sensor, which is a critical characteristic for the magnetic field sensor. [ABSTRACT FROM AUTHOR]

Sudden disaster events are usually unpredictable and uncontrollable, and how to achieve efficient and accurate disaster information dissemination is an important topic for society security. At present, social sensor networks which integrate human mobile sensors and traditional physical sensors are widely used in dealing with emergencies. Previous studies mainly focused on the impact of human mobility patterns on social sensor networks. In this article, based on the inherent autonomy property of human individuals, we propose a social sensor information dissemination model, which mainly focuses on the impact of the individual characteristics, social characteristics, and group information dissemination mode on social sensor networks. Specifically, the human sensor model is first constructed based on the inherent social and psychological attributes of human autonomy. Then, various information dissemination models such as one-to-one, one-to-many, and peer-to-peer are proposed by considering different transmission media and human interaction preferences. We simulate the environment of information dissemination in disaster events based on the NetLogo platform. Evaluation matrix is applied to test the performance of social sensor information dissemination model, such as event dissemination coverage, event delivery time, and event delivery rate. With the comparisons to epidemic model, social sensor information dissemination model shows excellent performance in improving the efficiency and accuracy of information transmission in disaster events. [ABSTRACT FROM AUTHOR]

Objectives: This study investigated the characteristics of workplace violence (WPV) against Chinese healthcare staff and their casualties after severe physical violence (PV). Methods: We scrutinized medical WPV incidents reported online and analyzed information on timing, location, violence, criminal incentives, and casualties following severe PV in China from 2010 to 2020. Results: WPVs were mostly committed by young and middle‐aged male family members of the patients, especially in the emergency department (49.1%), and mostly associated with dissatisfaction with treatment effect (28.9%) in general. High medical costs (62.5%) were the leading cause of verbal violence (VV), whereas men predominantly committed PV (OR = 4.217, 95% CI: 1.439–12.359) owing to dissatisfaction with the healthcare staff's attitude (P < 0.001). The victims were security personnel in most cases (81.1%). Nurses were generally more likely to experience PV (P < 0.05), while doctors were more likely to experience lethal PV (OR = 4.732, 95% CI: 1.42–15.772), which mostly happened in oncology (P < 0.05) and committed by visitors (P < 0.001). Slight injuries and mortality were more likely to be inflicted by being rejected for unreasonable demands and disappointed with the treatment effect (P < 0.05). Conclusions: Medical WPV has numerous reasons, locations, and diverse victims and offenders. Some severe WPVs have serious consequences. Therefore, it is recommended for the concerned authorities to adopt effective steps for appropriate legislative, security, and conflict‐resolution measures. [ABSTRACT FROM AUTHOR]

Indoor wideband electromagnetic radiation (EMR) over seven days and potential radiation sources were measured and analyzed in this article. The research results show that Wi-Fi and base station equipment are the main factors causing indoor electromagnetic exposure, and the radiation intensity of the former is much higher than the latter when the equipment is working. Also, the change of EMR over time conforms to the users’ daily work and rest cycle and contains a significant low-frequency component with a 24-h cycle and complex high-frequency components. Besides, the intensive use of electronic products by users has been proven to have a great impact on the frequency characteristics of the electric field, and the complexity of the time–frequency characteristics of EMR time series has increased, resulting in poor prediction results of the models such as the seasonal autoregressive moving average (SARIMA) model and the long short-term memory (LSTM) neural network. To this end, a prediction scheme combining wavelet transform and time-series analysis methods is proposed in this article. To verify the effectiveness of the proposed hybrid method, the samples of three days are exploited to perform a loop test of the prediction accuracy under different prediction steps. Besides, the results are compared with those obtained by single SARIMA and LSTM. The experimental results show that the proposed hybrid prediction method effectively predicts electric field radiation with complex frequency characteristics and significantly outperforms other methods in terms of prediction accuracy and prediction length. [ABSTRACT FROM AUTHOR]

A reliable design of physical unclonable function (PUF) based on spin-orbit torque (SOT) induced domain wall (DW) motion has been proposed and experimentally demonstrated. Magnetic DWs are nucleated and propagate in Ta/CoFeB/MgO heterostructures in which their device-to-device variation enables the PUF, while cycle-to-cycle variation in DW motion enables the reconfigurable design. Furthermore, field-free SOT switching has been observed in the chiral domain wall likely caused by the large Dzyaloshinskii-Moriya interaction (DMI) effect. The proposed DW motion based anti-counterfeiting device shows good promises as a CMOS-compatible PUF for hardware security. [ABSTRACT FROM AUTHOR]

Integrators are widely used in industrial controls, signal processing, and computing. However, traditional resistor–capacitor integrators incur leakage errors and zero drift, hindering their accuracy. By contrast, spintronic devices with good scalability and endurance for memory and logic applications in digital circuits have yet to be studied for analog circuit elements. Here, we propose a single-device spintronic integrator based on the current-controlled magnetic domain wall (DW). Continuous DW motion and correlated changes in the anomalous Hall resistance (or magneto-resistance) are encoded as an analog output signal, which is modulated by an input current through the spin–orbit-torque effect. Waveform transformation and phase-shift functions are demonstrated using Hall-bar devices. The spintronic integrator could pave the way for the spin-based analog computing with high reliability, high endurance, and good compatibility with the CMOS process. [ABSTRACT FROM AUTHOR]

The spin torque effects discovered in spintronics have a broad prospect for applications in information memory and logic devices, wherein deterministic switching is highly desired. Variations between devices originating from the fabrication process and inherently random physical features are detrimental to memory and logic devices; however, they are potential entropy sources for hardware security primitives. Here, we demonstrate two types of spin–orbit torque (SOT)-based reconfigurable physically unclonable functions (rPUFs) that are based on process-induced SOT switching current variations and SOT-induced domain wall (DW) nonlinear dynamics, respectively. The experimental results show that both rPUFs have excellent performance in terms of reliability and uniqueness, and the performance is sustained after reconfiguring. Furthermore, the DW nonlinear dynamics-based rPUF can be reconfigured for an unlimited number of times with high uniformity. We believe that our work paves a way for information security and expands the application fields of spintronics. [ABSTRACT FROM AUTHOR]