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Diabetic retinopathy (DR) is a common complication of diabetes which may lead to blindness. Early diagnosis can effectively prevent the deterioration of the disease and enable timely treatment. Ophthalmologists diagnose DR by observing ultra-wide optical coherence tomography angiography (UW-OCTA) images, which visualize unprecedented detail of DR lesions. In this paper, we propose an end-to-end task-specific network (TSNet) for joint DR grading and lesion segmentation of UW-OCTA images. Specifically, we design task-specific attention block to generate task-specific feature maps for respective segmentation and classification tasks. Furthermore, we devise task-specific fusion block to fuse the original task-specific feature map and augmented task-specific feature map for the following segmentation and classification decoders to generate DR lesion predictive mask and DR grading predictive result. Experiments on a public-available UW-OCTA dataset demonstrate that our model outperforms state-of-the-art (SOTA) multi-task models and achieves promising results on both DR lesion segmentation and DR grading classification tasks [ABSTRACT FROM AUTHOR]

Diffusion welding of YG8 and 40Cr was carried out by spark plasma sintering. The influence of Ni interlayer with different thicknesses varying from 0 to 500 μm on the welding morphology and mechanical properties of joints was studied. The fracture position moved from the cemented carbide substrate toward the connection interface with the increase in the thickness of the Ni intermediate layer. The joint with nickel-free interlayer and 100-μm thick fractured during electrical discharge machining due to the large residual stress. The bending strength of the joints enhanced with the increase in the Ni intermediate layer from 200 to 300 μm, and a maximum flexural strength of 982 MPa was obtained with the thickness of the Ni intermediate layer to be 300 μm, which was up to 97% of the strength of the cemented carbide substrate. However, the further increase in Ni intermediate layer from 300 to 500 μm resulted in a decrease in the bending strength, which was due to the coupled effects of residual stress and interlayer plastic constraint. Besides, fracture cracks were also observed at the interface of Ni/40Cr with the thickness of Ni intermediate layer to be 400 and 500 μm. The formation of Kirkendall pores in the interface of Ni/40Cr due to different diffusion coefficients of Fe (1.468 × 10−14 m2/s) and Ni (2.15 × 10−14 m2/s) was responsible for the crack initiation and propagation in the Ni/40Cr interface. [ABSTRACT FROM AUTHOR]

Background: Oxidative stress-induced retinal pigment epithelium (RPE) cell damage is a major factor in age-related macular degeneration (AMD). Vitamin D3 (VD3) is a powerful antioxidant and it has been suggested to have anti-aging properties and potential for treating AMD. This study aimed to investigate the effect of VD3 on RPE cell oxidative apoptosis of RPE cells in order to provide experimental evidence for the treatment of AMD. Methods: Human retinal pigment epithelial cell 19 (ARPE-19) cells were divided into four groups: blank group (untreated), model group (incubated in medium with 400 μmol/L H2O2 for 1 h), VD3 group (incubated in medium with 100 μmol/L VD3 for 24 h), and treatment group (incubated in medium with 400 μmol/L H2O2 for 1 h and 100 μmol/L VD3 for 24 h). Cell viability, cell senescence, ROS content, expression levels of vitamin D specific receptors, Akt, Sirt1, NAMPT, and JNK mRNA expression levels, SOD activity, and MDA, GSH, and GPX levels were measured. Results: We first established an ARPE-19 cell stress model with H2O2. Our control experiment showed that VD3 treatment had no significant effect on ARPE-19 cell viability within 6–48 h. Treating the stressed ARPE-19 cells with VD3 showed mixed results; caspase-3 expression was decreased, Bcl-2 expression was increased, MDA level of ARPE-19 cells was decreased, GSH-PX, GPX and SOD levels were increased, the relative mRNA expression levels of Akt, Sirt1, NAMPT were increased (P < 0.05), and the relative mRNA expression level of JNK was decreased (P < 0.05). Conclusion: VD3 can potentially slow the development of AMD. [ABSTRACT FROM AUTHOR]

Unpiloted technology requires attitude measurement from global positioning system to adjust the moving direction of car. However, the measurement result from the satellites suffer from fluctuation, which reduces the control ability of system. Thus, we propose our novel algorithm. First, it builds double difference observation equation based the measurements from two satellites. Second, the least squares algorithm is utilized to calculate double difference integer ambiguity. Third, it constructs the length of baseline to calculate baseline vector, which improves the solution success rate of integer ambiguity and reduces frequency of mutation occurs in attitude angle solving process. Finally, baseline vector is employed to solve the attitude angle of unpiloted car. The extensive experimental results demonstrate that the success rate of the attitude reach 95% within 2° of error under the constraint of the baseline, and the error of the attitude is less than 1° under the dynamic condition. [ABSTRACT FROM AUTHOR]

A low power clock generator with self-calibration for UHF RFID tags compatible with the EPCglobal Class-1 Gen-2 (EPC Gen2) standard is presented. By utilizing the timing information of the reader to tag (R ⇒ T) link symbols, the frequency accuracy of the calibrated clock can meet the stringent requirement of the standard. Designed in a 0.18 μ m standard CMOS technology, simulation results show that the frequency error of the clock source is only from − 2.07 to + 1.4% of the target frequency of 2.56 MHz. The power consumption is only 720 nW. [ABSTRACT FROM AUTHOR]

Quantum teleportation is an essential concept in quantum communication and quantum computing. bidirectional controlled quantum teleportation extends traditional quantum teleportation, transmitting information in two directions while ensuring security. It has become a hot topic of research. A bidirectional controlled quantum teleportation protocol based on eight-qubit entangled states is proposed. This protocol enables Alice and Bob to transmit two-qubit quantum states to each other under the control of a supervisor. The specific steps and derivation process of the theoretical plan were proposed, and the theory proved the correctness of the plan. To understand the impact of noise in quantum teleportation, the fidelity changes of this scheme were analysed under different types of noise channels. The influencing factors of fidelity were determined, which will provide a basis for optimising the transmission scheme and improving transmission performance in the future. An experimental circuit was built and simulated through the IBM Quantum Experience platform to verify the correctness and feasibility of the theory. The results showed that this solution can successfully reconstruct the sent quantum state with high fidelity. Finally, the security analysis of this scheme was conducted and compared with other traditional related schemes. This scheme has higher efficiency, lower resource consumption, simpler operation, and stronger security. The advantages of the scheme were pointed out. [ABSTRACT FROM AUTHOR]

Direct seeding rice (DSR) is a cost-saving and efficient production technology. It is of great significance to identify the characteristics of nitrogen demand of DSR in further improving yield and nitrogen use efficiency. In this study, a field experiment was carried out with inbred rice (HHZ) and hybrid rice (FLY4, YLY6) in Wuhan, China, in 2020 and 2021, respectively. Two fertilization ratios are as follows: basal fertilizer: tillering fertilizer: panicle fertilizer = 5:2:3 (T0); basal-tillering fertilizer: panicle fertilizer = 6:4. Four first fertilization time set as follows: T1, basal-tillering fertilizer was applied at 10 days after seeding (DAS); T2, basal-tillering fertilizer was applied at 15 DAS; T3, basal-tillering fertilizer was applied at 20 DAS; and T4, basal-tillering fertilizer was applied at 25 DAS. The changes of yield and yield components, above-ground biomass accumulation, nitrogen use efficiency, harvest index (HI), and leaf SPAD were investigated. The results showed that the yield of DSR could be significantly increased by properly postponing the first basal-tillering fertilization time. Compared with the T0, the basal-tiller fertilizer application at 20 DAS could significantly increase the yield by 15.1%, mainly because the number of spikelets per unit area increased by 18.9% on average across years and varieties. Delaying the first application time of basal-tillering fertilizer in DSR can significantly increase the biomass accumulation of above-ground leaves and stems and increase the yield, but with the decrease of HI in T3 and T4. In addition, delaying the first application time of basal-tiller fertilizer could also effectively improve the nitrogen use efficiency by 12.1% in DSR. The PFP and AE of T3 were significantly increased by 15.1% and 55.9% compared with T0, respectively. Delayed basal-tiller fertilizer treatment laid the foundation for maintaining higher leaf SPAD value in later developmental stage. To sum up, delaying the first application time of basal-tillering fertilizer was beneficial to build a better population of DSR, with high yield and nitrogen use efficiency, which has important reference significance for further optimization of light and simplified direct seeding nitrogen technology of rice. However, the delay of basal-tillering fertilizer application time leads to the increase of biomass, accompanied by the risk of plant lodging. Therefore, the optimal application amount of basal-tillering fertilizer needs to be further explored. [ABSTRACT FROM AUTHOR]

Atrazine, a widely used herbicide in agriculture, is detrimental to both the ecological environment and human health owing to its extensive use, poor degradability, and biotoxicity. The technology commonly used to remove atrazine from water is activated carbon adsorption, but it has the problems of difficult recovery, secondary contamination, and a low removal rate. To efficiently remove atrazine from agricultural wastewater, in this study, a new environmental material, embedding immobilization (EI)-Co- and Zr-modified activated carbon powder (Co/Zr@AC), was prepared by immobilizing the bimetallic Co/Zr@AC via EI technique and employed to remove atrazine. When preparing EI-Co/Zr@AC, the single-factor experiment was conducted and determined the optimal preparation conditions: sodium alginate 2.5% (wt), calcium chloride 4.0% (wt), Co/Zr@AC 1.0% (wt), and bentonite 2.0% (wt). The prepared EI-Co/Zr@AC has a three-dimensional mesh structure and many pores and also possesses good mass transfer performance and mechanical properties. The removal efficiency by EI-Co/Zr@AC for the removal of 5.0 mg/L atrazine from 50 mL was 94.1% at pH 7.0 and 25°C, with an EI-Co/Zr@AC dosage of 0.8 g. The mechanistic study showed that the pseudo-second-order kinetic model could describe the removal process better than the pseudo-first-order kinetic model, and the Freundlich isotherm model fit better than other isotherm models. Additionally, the synthesized EI-Co/Zr@AC spheres demonstrated good reusability, with the atrazine removal rate remaining 70.4% after five cycles, and the mechanical properties of the spheres were stable. [ABSTRACT FROM AUTHOR]

Currently, quantum communication is gradually moving from theory to reality. Considering the practical application of quantum communication, more effective and feasible quantum communication schemes are needed. The feasibility of quantum communication schemes can be effectively verified through the three-dimensional reconstruction technology in quantum computers, namely, quantum state tomography. Therefore, this paper creatively proposes a scheme for separating arbitrary two-qubit quantum information using three-qubit entangled states and Bell states as quantum channels and uses IBM Experience platform and quantum state tomography technology for experimental verification. A corresponding quantum circuit is designed on the IBM Quantum Experience cloud platform for experimental simulation. Without loss of generality, we use the RawFeatureVector circuit and a random function of Qiskit to generate the two-qubit state in our scheme. And on this basis, entirely and comprehensively extracted massive data of quantum state information to calculate fidelity, proving that the scheme is safe and effective. Finally, to ensure the communication security, we have analyzed the security of the scheme. [ABSTRACT FROM AUTHOR]

Mo-5Ta targets were prepared by the spark plasma sintering (SPS) technology under the sintering temperatures of 1 400–1 600 °C, the holding times of 0–20 min, and the axial pressure of 30 MPa. The microstructure, performance, and grain growth kinetics of Mo-5Ta sputtering targets were studied. With the increase of sintering temperatures and times, Ta can more dissolve in Mo and form a Mo(Ta) solid solution. The grain sizes of Mo-5Ta targets remain unchanged at low temperatures (1 400–1 500 °C) while increasing significantly at high temperature (1 600 °C) with the extension of the holding time. In addition, the densities and Vickers hardness (HV0.5) first ascend and then decrease with sintering proceeding. The thermal conductivity is positively correlated with the grain size and density, as a result of their joint action. Based on the comprehensive analysis, the grain growth is dominated by the combination of boundary diffusion and volume diffusion. When n=2, the activation energies of grain growth under holding times of 5, 10, 20 min are calculated as 762.70, 617.86, and 616.52 kJ/mol, respectively. [ABSTRACT FROM AUTHOR]

We consider the existence of normalized solutions to the following nonlinear Schrödinger system - Δ u + λ 1 u = μ 1 | u | p - 2 u + β v in R N , - Δ v + λ 2 v = μ 2 | v | q - 2 v + β u in R N , under the mass constraints ∫ R N | u | 2 d x = a 1 2 and ∫ R N | v | 2 d x = a 2 2 , where 2 < p ≤ 2 + 4 N ≤ q ≤ 2 ∗ , β , μ 1 , μ 2 > 0 , a 1 , a 2 > 0 , and λ 1 , λ 2 ∈ R appear as Lagrange multipliers. Under different character on p, q with respect to the mass critical exponent, we prove several existence results and precise asymptotic behavior of these solutions as (a 1 , a 2) → (0 , 0) . These cases present substantial differences with respect to purely mass subcritical or mass supercritical situations. [ABSTRACT FROM AUTHOR]

The interaction between machine learning and quantum physics has given rise to an emerging frontier of quantum machine learning research. In this line, quantum classifiers have received significant attention recently as a quantum device designed to solve the classification problem in machine learning. In this paper, we propose a new variational quantum multi-class classifier that uses l o g 2 N qubits to represent N labels, converts the labels into different quantum states, and optimizes the circuit parameters by the fidelity between the true label state and the output state. Our method effectively reduces the width of the circuit and lowers the number of auxiliary particles needed from N to l o g 2 N . We conducted simulation experiments on several datasets. On the MNIST handwritten digits dataset, we achieved 99.8% accuracy for 4 classifications and 97% for 8 classifications. On the CIFAR-10 dataset, we obtained 85.3% accuracy for 8 classifications. Finally, on the CIFAR-100 dataset, we reached 76% accuracy for 16 classifications. [ABSTRACT FROM AUTHOR]

Conventional grouting methods present challenges in achieving effective surface rock grouting and avoiding interference with concrete grouting and construction processes. The proposed approach includes reserving rock overburden, controlling grouting pressure and concentration, using a segmented grouting method, and selecting appropriate materials to develop a key method for consolidation grouting. This method not only overcomes the problems associated with the conventional consolidation grouting method but also effectively protects the thin layer of breccia lava in the Baihetan Dam foundation and solves the problem of unloading and relaxation of columnar jointed basalt caused by exposed consolidation grouting. The results show that the post grouting inspection hole permeability qualification rate is 99.3%, with the proportion of high-speed measuring points of various rock types ranging from 91.8% to 93.3%, and the proportion of low-speed measuring points ranging from 2.0% to 2.9%. The drop rate of the grout take of sequence I and sequence II is between 30%–60%, except for some dam sections. These results indicate that the proposed method for consolidation grouting meets the design requirements. The findings have significant implications for the design and construction of consolidation grouting in similar projects. [ABSTRACT FROM AUTHOR]

Exosomal PD-L1 (exoPD-L1) has recently received significant attention as a biomarker predicting immunotherapeutic responses involving the PD1/PD-L1 pathway. However, current technologies for exosomal analysis rely primarily on bulk measurements that do not consider the heterogeneity found within exosomal subpopulations. Here, we present a nanoscale cytometry platform NanoEPIC, enabling phenotypic sorting and exoPD-L1 profiling from blood plasma. We highlight the efficacy of NanoEPIC in monitoring anti-PD-1 immunotherapy through the interrogation of exoPD-L1. NanoEPIC generates signature exoPD-L1 patterns in responders and non-responders. In mice treated with PD1-targeted immunotherapy, exoPD-L1 is correlated with tumor growth, PD-L1 burden in tumors, and the immune suppression of CD8+ tumor-infiltrating lymphocytes. Small extracellular vesicles (sEVs) with different PD-L1 expression levels display distinctive inhibitory effects on CD8 + T cells. NanoEPIC offers robust, high-throughput profiling of exosomal markers, enabling sEV subpopulation analysis. This platform holds the potential for enhanced cancer screening, personalized treatment, and therapeutic response monitoring. Exosomal PD-L1 (exoPD-L1) is a biomarker predicting immunotherapeutic responses. Here the authors report NanoEPIC, a nanoscale cytometry platform that enables phenotypic sorting and exoPD-L1 profiling from blood plasma by using magnetic-activated ranking to differentiate exosomal subpopulations. [ABSTRACT FROM AUTHOR]

This paper presents an improved quantum dialogue protocol based on the HHL algorithm. In this protocol, Alice and Bob want to transmit their classical information to each other. Combining the HHL algorithm and quantum linear equation ensures that eavesdroppers cannot steal the data of communicators. In addition, communicators will connect come HHL quantum circuit constructed in this scheme with the swap test circuit to calculate the solution rather than directly measuring the result, which can improve the solution speed. Security analysis shows that this scheme is more secure than other general quantum dialogue schemes, and it can realize information protection in extreme cases, with good security and higher transmission efficiency. [ABSTRACT FROM AUTHOR]

Dissolved organic matter (DOM) in wastewater interacts with heavy metal particles in aquatic environments, which changes their dynamics and bioavailability. For quantifying the DOM, an excitation-emission matrix (EEM) paired alongside parallel factor analysis (PARAFAC) is typically employed. However, a drawback of PARAFAC has been revealed in recent studies, i.e., the rise of overlapping spectra or wavelength shifts in fluorescent components. Here, traditional EEM–PARAFAC and, for the first time, two-dimensional Savitzky–Golay second-order differential–PARAFAC (2D-SG-2nd-df–PARAFAC) were used to study the DOM–heavy metal binding. The samples from four treatment units of a wastewater treatment plant, i.e., influent, anaerobic, aerobic, and effluent, underwent the process of fluorescence titration with Cu2+. Four components were separated with dominant peaks in regions I, II, and III (proteins and fulvic acid-like) through PARAFAC and 2D-SG-2nd-df–PARAFAC. A single peak was observed in region V (humic acid-like) by PARAFAC. In addition, Cu2+–DOM complexation indicated clear differences in DOM compositions. The binding strength increased between Cu2+ and fulvic acid-like components in contrast to protein-like components from influent to the effluent, and increasing fluorescence intensity with the addition of Cu2+ in the effluent indicated changes in their structural composition. Moreover, when comparing both methods, the 2D-SG-2nd-df–PARAFAC provided the components without peak shifts and better fitting for Cu2+–DOM complexation model, demonstrating it to be a more reliable technique compared to only traditional PARAFAC for DOM characterization and quantifying metal–DOM in wastewater. [ABSTRACT FROM AUTHOR]

In recent years, the behavior recognition technology based on Wi-Fi devices has been favored by many researchers. Existing Wi-Fi-based human behavior recognition technology mainly uses classification algorithms to construct classification models, which has problems such as inaccurate behavior segmentation, failure to extract deep-level features from the original data and design classification models matching the proposed features in the process of behavior recognition. In order to solve above problems, this paper proposes a window variance comparison method by combining the adaptive thresholds calculated to achieve effective segmentation of multiple discontinuous human behaviors, then uses the short-time Fourier algorithm to extract time-frequency features of individual behavior, and extracts the graph structure data from the autocorrelation matrix of time-frequency features and the features themselves. A graph neural network is built for behavior recognition. The experimental results show that the segmentation accuracy of the behavior segmentation method in the two scenes is 0.964 and 0.993, which is better than the existing threshold-based behavior segmentation methods. In addition, this paper extracts graph structure data by spectral energy change method and builds behavior recognition model by using graph neural network, and the recognition accuracy is significantly improved compared with the traditional classification algorithm. [ABSTRACT FROM AUTHOR]

Aqueous iron batteries are appealing candidates for large-scale energy storage due to their safety and low-cost aspects. However, the development of aqueous Fe batteries is hindered by their inadequate long-term cycling stability. Here, we propose the synthesis and application as positive electrode active material of cross-linked polyaniline (C-PANI). We use melamine as the crosslinker to improve the electronical conductivity and electrochemical stability of the C-PANI. Indeed, when the C-PANI is tested in combination with a Fe metal negative electrode and 1 M iron trifluoromethanesulfonate (Fe(TOF)2) electrolyte solution, the coin cell can deliver a specific capacity of about 110 mAh g−1 and an average discharge voltage of 0.55 V after 39,000 cycles at 25 A g−1 with a test temperature of 28 °C ± 1 °C. Furthermore, mechanistic studies suggest that Fe2+ ions are bonded to TOF− anions to form positively charged complexes Fe(TOF)+, which are stored with protons in the C-PANI electrode structures. Finally, we also demonstrate the use of C-PANI in combination with a polymeric hydrogel electrolyte to produce a flexible reflective electrochromic lab-scale iron battery prototype. Aqueous iron batteries are safe and cost-effective candidates for large-scale energy storage. However, their long-term cycling stability is inadequate. Here, the authors propose a crosslinked polyaniline-based positive electrode for high-power aqueous iron batteries with electrochromic properties. [ABSTRACT FROM AUTHOR]

Quantum teleportation is a hot topic of extensive research at present, and bidirectional quantum teleportation is one of the important research directions. In this paper, we propose a scheme to realize controlled bidirectional quantum teleportation by using a six-particle as the quantum channel. In this scheme, the communication parties Alice and Bob need to cooperate to send and receive unknown arbitrary particle states, which can’t achieve the purpose alone. During the transmission, Alice and Bob only need to perform simple Bell state measurement and single-particle measurement, and the measurement steps are few. Finally, the purpose can be achieved by performing some appropriate unitary transformations. We validate the scheme on the IBM Quantum Experiment platform and the feasibility by data. In terms of security, we discuss the method of ensuring communication security when this scheme is subjected to external and internal attacks. Finally, we compare it with other bidirectional quantum teleportation schemes, our scheme consumes fewer quantum resources and classical resources, operates fewer times, and has higher transmission efficiency, which fully highlights the advantages of this scheme. [ABSTRACT FROM AUTHOR]

Nucleic acid sensing powered by the sequence recognition of CRIPSR technologies has enabled major advancement toward rapid, accurate and deployable diagnostics. While exciting, there are still many challenges facing their practical implementation, such as the widespread need for a PAM sequence in the targeted nucleic acid, labile RNA inputs, and limited multiplexing. Here we report FACT (Functionalized Amplification CRISPR Tracing), a CRISPR-based nucleic acid barcoding technology compatible with Cas12a and Cas13a, enabling diagnostic outputs based on cis- and trans-cleavage from any sequence. Furthermore, we link the activation of CRISPR-Cas12a to the expression of proteins through a Reprogrammable PAIRing system (RePAIR). We then combine FACT and RePAIR to create FACTOR (FACT on RePAIR), a CRISPR-based diagnostic, that we use to detect infectious disease in an agricultural use case: honey bee viral infection. With high specificity and accuracy, we demonstrate the potential of FACTOR to be applied to the sensing of any nucleic acid of interest. Nucleic acid sensing involving CRISPR technologies is powerful but has certain limitations, such as PAM sequence requirements and limited multiplexing. Here, authors report a CRISPR-based barcoding technology which enables multiple outputs from any target sequence, based on cis- and trans-cleavage. [ABSTRACT FROM AUTHOR]

Single atom catalysts (SACs) were reported to demonstrate exciting catalytic features for a number of reactions, including hydrogen evolution reaction (HER). However, the true role of these single atom sites in catalysts remains elusive, particularly for those prepared via pyrolysis, where the formation of active nanoparticle counterparts is often unavoidable. Here we report a Ru based catalyst (Ru embedded in N doped carbon spheres (Ru/NPCS)) comprising of both Ru nanoclusters and Ru single sites, who demonstrates activity exceeding Pt catalyst and mass activity among the best of the Ru based catalysts under acidic conditions. The integration of proton exchange membrane water electrolysis with Ru/NPCS as a cathode exhibited an excellent hydrogen generation activity and extraordinary stability (during 120 h of electrolysis) with a 1/48 Ru loading (16.5 µgRu·cm−2) of a commercial 20% Pt/C catalyst. Through precisely tailoring the dispersion status of the catalysts, we reveal that while ruthenium nanoclusters actively catalyze HER via Volmer-Tafel mechanism, the Ru SACs barely catalyze HER, with H* adsorption difficult to occur. Moreover, no synergy between Ru SACs and Ru cluster is revealed, meaning the Ru SACs act as a spectator rather than active species during H2 evolution. [ABSTRACT FROM AUTHOR]

Drought stress is one of the major threats to rice production. The weakening of leaf photosynthesis due to drought is the main reason for the reduction of grain yield, but its mechanism is still obscure. The objectives of this study were to reveal the physiological mechanism of drought stress affecting photosynthetic capacity and grain yield. Pot experiments were conducted with drought-tolerant cultivars Hanyou113 (HY113) and Zhonghan3 (ZH3) and drought-sensitive cultivar Huanghuazhan (HHZ) under four water management treatments (traditional flooding (CK), mild drought stress (LD), moderate drought stress (MD) and severe drought stress (HD)) at heading stage in 2013 and 2014. Compared with CK, grain yield was significantly reduced by 14.9%, 30.8%, and 12.8% in HY113, HHZ, and ZH3 under LD, 32.9%, 33.7%, and 22.9% in HY113, HHZ and ZH3 under MD and 53.6%, 45.6%, and 30.7% in HY113, HHZ, and ZH3 under HD, respectively. The photosynthetic rate (Pn) decreased by 49.0% from 20.0 to 10.2 µmol m−2 s−1 in HY113, and 67.6% from 23.4 to 7.58 µmol m−2 s−1 in HHZ, and 39.3% from 23.4 to 14.2 µmol m−2 s−1 in ZH3 under HD. The Pn of HHZ was similar to that of ZH3 under CK conditions. During the drought periods from LD to HD at heading stage, the leaf water potential (LWP) reduced 31.9%, 54.8%, and 15.7% in HY113, HHZ, and ZH3, respectively. The non-photochemical quenching (NPQ) of HY113, HHZ, and ZH3 flag leaves increased by 150%, 97.6%, and 218%, respectively. The effective quantum yield of PSII photochemistry (ΦPSII) of flag leaves reduced by 20.3%, 11.9%, and 22.1% in HY113, HHZ, and ZH3, respectively. The enzymatic activities of superoxide dismutase (SOD), peroxidase (POD), and catalase (CAT) increased by 11.4%, 18.0%, and 21.8% in HY113, and 13.2%, 14.3%, and 30.9% in HHZ, and 13.4% 21.7%, and 17.6% in ZH3 under MD on average across two seasons. The yield reduction of drought-resistant cultivars (HY113, ZH3) was smaller than that of conventional cultivars (HHZ). Maintaining leaf water potential (LWP), Pn, photosystem II (PSII) original light energy conversion efficiency, non–photochemical quenching coefficient (NPQ), and increasing in the ratio of photochemical reaction energy in fluorescence and antioxidant enzyme activity is the physiological basis to achieve a relatively high photosynthesis. These traits could be the target for breeder to develop drought-tolerant varieties. [ABSTRACT FROM AUTHOR]

Quantum information splitting is one of the important applications of quantum entanglement. In this paper, we propose a scheme for information splitting of arbitrary five-qubit state using a four-qubit entangled state as the quantum channel. In the scheme, Alice performs a simple gate operation and single-qubit measurement on the qubit, and Bob can reconstruct the initial state by performing the appropriate unitary operation and introducing three auxiliary qubits based on Alice’s measurement results. We validate the scheme on the IBM Quantum Experience platform and also ensure the security of the scheme by introducing four quantum states. Finally, this scheme is compared with the other two schemes, and the results show that our scheme is sufficiently superior. [ABSTRACT FROM AUTHOR]

This paper aims to examine the nexus among carbon dioxide (CO2) emissions, urbanization level and industrial structure in North China over the period 2004–2019, according to an expanded Cobb-Douglas production function. The panel econometric techniques are employed to complete the empirical analysis, including cross-sectional correlation test, panel unit root test, panel co-integration test, and panel Granger causality test. The empirical results support the long-term equilibrium relationship among CO2 emissions, urbanization level and industrial structure in North China, and the urbanization level contributes most to CO2 emissions, followed by fossil energy consumption. Furthermore, the bidirectional causality between CO2 emissions and urbanization level and unidirectional causality from industrial structure to CO2 emissions are found in North China, indicating that urbanization level and industrial structure have significant impacts on CO2 emissions. Finally, according to the empirical findings, several policy suggestions are proposed for the purpose of reducing CO2 emissions in North China. [ABSTRACT FROM AUTHOR]

Most previous work concentrated on the thermal smoke temperature distribution in traditional single tunnel fires. However, few investigations have studied the effects of branch tunnel and longitudinal fire source location on thermal smoke temperature beneath the ceiling. In this paper, a series of experiments were performed in a 1:10 reduced scale branched tunnel to investigate the longitudinal fire location effects on the thermal smoke temperature distribution beneath the ceiling. Thirteen longitudinal fire locations and three heat release rates were considered. The main conclusions are summarized as follows: The thermal smoke temperature near the fire source is obviously different for various longitudinal fire locations, while the temperature in the area far from the fire source is basically the same. The dimensionless longitudinal thermal smoke temperature beyond 0.75 m downstream from the fire source in the main tunnel is not obviously affected by the longitudinal fire location, which can be well predicted by Li's model. However, the attenuation coefficient is obviously larger than that in traditional single tunnel due to the existence of branch tunnel. Moreover, when the fire source moves away from the intersection region to upstream or downstream, the thermal smoke temperature in the branch tunnel shows a decrease. A modified model is proposed to describe the longitudinal temperature decay in branch tunnel taking the longitudinal fire location into account, which is reasonably well fitting with experimental results. The results in this paper are essential for better understanding of thermal smoke temperature in branched tunnel and providing references for fire safety design of branched tunnels. [ABSTRACT FROM AUTHOR]

Quantum communication is a kind of communication mode which uses quantum physical characteristics to ensure the security of information transmission channel. It is widely concerned because it is different from the traditional cryptographic communication. Among them, quantum teleportation is the main research field and the key technology to achieve secure communication. In this scheme, four-qubit entangled state is used as quantum channel to transmit unknown seven-qubit entangled state. Firstly, Alice will deform the unknown seven-qubit entangled state. After transmission, Alice performs a series of operations on the particles she owns, and performs single-qubit measurement operation, and tells Bob the measurement results through the classical channel. After the measurement, Bob can reconstruct the unknown seven-qubit entangled state by sending the measurement results and the corresponding unitary operation, and with the help of auxiliary particles. We also carried out a security analysis to prove that the scheme is safe, and use the IBM platform for experimental verification, compared with the previous scheme, the scheme is more simple and efficient. [ABSTRACT FROM AUTHOR]

This article presents a design of a novel swimming mechanism based on a linkage mechanism. The generated motions of the proposed mechanism mimic the purely aquatic locomotion of frogs such as Xenopus laevis (X. laevis), including both the motions of the hind legs and the webbed foot. A six-bar linkage mechanism is employed in this study combing with a spatial linkage mechanism to simplify the overall mechanism. Attributes to the optimal design, the number of Degrees of Actuations (DoA) reduces to two in each hindlimb, which realizes miniaturization in the current study. Kinematic analysis is conducted to analyze the locomotion of the spatial mechanism. The hydrodynamic model based on the blade element theory is established to estimate the swimming performance of the designed mechanism. The peak thrust (approximately 0.2 N) is dramatically larger than the minimum drag (−0.023 N) observed in the experiment which increases the efficiency of the prototype’s swimming. [ABSTRACT FROM AUTHOR]

Recently, cobalt-nickel nanoparticles with ferromagnetic properties are often used in wave absorption materials and sensors. In this paper, after surface treatment of carbon fiber, a simple solvothermal method was used to grow cobalt-nickel alloy particles on the surface of carbon fiber, which was expressed as CoNi alloy/carbon fibers composite. The surface treatment process of carbon fiber, the structures, morphology, chemical, and electromagnetic parameters of CoNi alloy/CFs composites were analyzed in detail. In the composite material, more loss mechanisms are introduced to balance impedance matching, thus achieving designable electromagnetic parameters, ultra-thin thickness, low density, wide absorption frequency band, and strong electromagnetic absorption capacity. The effects of permittivity and permeability on the absorbing properties of the composites were compared under different CoNi alloy content (15–45%). The absorption frequency of composites moves to high-frequency and shows better performance, with the minimum RL of − 55.4 dB at 17.1 GHz and the effective absorption bandwidth is 4.1 GHz (thickness 1.2 mm). Accordingly, as-prepared CoNi alloy/CFs composites could be used as electromagnetic wave absorbing materials with great application prospects. [ABSTRACT FROM AUTHOR]

With the increasing maturity and popularity of wireless network techniques, indoor Wi-Fi positioning will inevitably become a significant application in indoor location-based services. In this circumstance, there is normally no control over the number of access points (APs) and the diversity of the Wi-Fi signal distribution, which may significantly deteriorate the positioning effectiveness as well as the system efficiency. To address this issue, we first adopt the fuzzy information entropy-based fuzzy rough set to conduct redundant APs reduction. Second, we calculate the Wasserstein distance between the signal distribution at the target position and the one at each Reference Point (RP) by the Wasserstein distance method. Third, the multisource information fusion method based on the Dempster–Shafer evidence theory is exerted to construct the matching RPs set. Finally, the abundant experiments and results in a realistic indoor Wi-Fi environment testify that the proposed method is able to preserve satisfactory localization performance as well as reduce the computation overhead of localization. [ABSTRACT FROM AUTHOR]

Platinum (Pt) has found wide use as an electrocatalyst for sustainable energy conversion systems1–3. The activity of Pt is controlled by its electronic structure (typically, the d-band centre), which depends sensitively on lattice strain4,5. This dependence can be exploited for catalyst design4,6–8, and the use of core–shell structures and elastic substrates has resulted in strain-engineered Pt catalysts with drastically improved electrocatalytic performances7,9–13. However, it is challenging to map in detail the strain–activity correlations in Pt-catalysed conversions, which can involve a number of distinct processes, and to identify the optimal strain modification for specific reactions. Here we show that when ultrathin Pt shells are deposited on palladium-based nanocubes, expansion and shrinkage of the nanocubes through phosphorization and dephosphorization induces strain in the Pt(100) lattice that can be adjusted from −5.1 per cent to 5.9 per cent. We use this strain control to tune the electrocatalytic activity of the Pt shells over a wide range, finding that the strain–activity correlation for the methanol oxidation reaction and hydrogen evolution reaction follows an M-shaped curve and a volcano-shaped curve, respectively. We anticipate that our approach can be used to screen out lattice strain that will optimize the performance of Pt catalysts—and potentially other metal catalysts—for a wide range of reactions.By depositing platinum shells on palladium-based nanocubes, the strain can be controlled by through phosphorization and dephosphorization, making it possible to tune the electrocatalytic activity of the platinum shells. [ABSTRACT FROM AUTHOR]

Two-dimensional materials have already been considered as promising microwave absorbing materials due to their unique and charming layered structure. However, it is difficult to achieve excellent absorption performance at a thin thickness. Herein, the polyhedral Fe3O4 was prepared in-situ using sheet-shaped carbonyl iron powder, which not only retained the sheet-like structure of carbonyl iron powder but also formed polyhedral Fe3O4 on the surface. By tuning the ratio of Ti3C2TX/carbonyl iron powder/Fe3O4 microwave absorption capabilities in terms of the minimum reflection loss (RL) value and absorber thickness could be readily optimized. This result is verified by the explanation of the quarter-wavelength law and impedance matching degree. Specifically, when the thickness of the C–F–M 10% composite material is 2.2 mm, the minimum RL value at 9.16 GHz is − 52.1 dB, and the effective absorption bandwidth is 3.32 GHz. The thickness of the C–F–M 15% composite is 2.0 mm, the minimum RL value at 11.12 GHz is − 49.9 dB, and the effective absorption bandwidth is 4.59 GHz. Therefore, Ti3C2TX composite material is expected to become a candidate material for ultra-thin and lightweight absorbers. [ABSTRACT FROM AUTHOR]

In this paper, the fabrication of a highly orientated Bi2Fe4O9 (BFO) photoelectrode in the presence of two-dimensional (2D) graphene oxide (GO) was reported. It was found that the GO can be used as a template for controlling the growth of BFO, and the nanoplate composites of BFO/reduced graphene oxide (RGO) with a high orientation can be fabricated. The thickness of the nanoplates became thinner as the ratio of GO increased. As a result, the ferroelectric spontaneous polarization unit arranges itself in the space in a periodic manner, leading to the formation of a polarization field along a special direction. Therefore, the created built-in electric field of the nanoplate composites of BFO/RGO is improved upon the increase of the amount of RGO. As expected, carrier separation is enhanced by the built-in electric field, therefore substantially enhancing the photoelectrochemical (PEC) activity of water splitting compared to pure BFO under the irradiation of visible-light. [ABSTRACT FROM AUTHOR]

In this paper, we study the following nonlinear Choquard equation 0.1 (- Δ) s u + V (x) u = (I α ∗ | u | 2 α , s ∗ ) | u | 2 α , s ∗ - 2 u , u ∈ D s , 2 (R N) , where s ∈ (0 , 1) , N > 2 s , 0 < α < N and 2 α , s ∗ = N + α N - 2 s is the critical exponent in the sense of Hardy–Littlewood–Sobolev inequality. We showed that Eq. (0.1) has at least one bound state solution if ‖ V (x) ‖ L N 2 s is suitably small, by proving a version to the Fractional operator in R N of the Global Compactness result due to Struwe (see Struwe 1984) [ABSTRACT FROM AUTHOR]

Minimizers are widely acknowledged cross-linguistically to denote a minimal quantity, extent or degree. With respect to minimizers in Mandarin Chinese, Shyu (Linguistics 54:1355–1395, 2016) claims that their so-called negative polarity is purely syntactically determined and is facilitated by the lian...dou ('including...all') EVEN construction. Within the framework of Dynamic Syntax (Kempson et al., Dynamic syntax: the flow of language understanding, Blackwell, 2001; Cann et al., The dynamics of language, Elsevier, 2005) which allows for interaction between syntactic, semantic and pragmatic information, we demonstrate that the total negation is actually derived from the interaction between syntax, semantics and pragmatics, rather than being determined by purely syntactic means. [ABSTRACT FROM AUTHOR]

This paper proposes a scattering area model for processing multipath parameters achieve single base station positioning. First of all, we construct a scattering area model based on the spatial layout of obstacles near the base station and then collect the multipath signals needed for positioning and extract parameters. Second, we use the joint clustering algorithm improved by k-means clustering and mean shift clustering algorithm to process the parameters and extract useful information. Third, the processed information is combined with the spatial layout information of the scattering area model to construct equations, and then the solving problem of equations is converted into a least-squares optimization problem. Finally, the Levenberg-Marquardt (LM) algorithm is used to solve the optimal solution and estimate the mobile target position. The simulation results show that the positioning algorithm in this paper can be used by a single base station to locate the target in an outdoor non-line-of-sight (NLOS) environment, and the accuracy is improved compared with the traditional positioning algorithm. [ABSTRACT FROM AUTHOR]

Most previous work concentrated on the one-sided upward flame spread under limited conditions. However, few investigations have studied the effects of limited distance between wall and fuel surface on two-sided upward flame spreading. In this paper, a series of upward flame spread experiments were conducted using 0.65 mm thick, 130 cm tall and 4.0 cm wide flax fabric sheets with various limited distance of 1.0 cm–3.5 cm. The flame shape, flame length, flame standoff distance, pyrolysis spread rate and surface temperature were measured and analyzed. An unexpected but interesting behavior of one-sided flame blow off was observed in upward flame spread. When limited distance is no more than 1.5 cm, the one-sided flame blow off behavior occurs on unlimited side, whereas this behavior occurs on limited side for 2.0 cm–3.5 cm limited distance. This result could be qualitatively explained by Damkohler number Da, which could be characterized by two parameters of induced flow velocity and heat flux received by virgin surface. Moreover, the maximum flame length, steady flame length, maximum spread rate and steady spread rate first increase and then decrease as the limited distance. This non-monotonicity trend is determined by heat flux profiles in the preheating zone, which is due to the combined limited distance effects of restricting oxygen supply, chimney effect and wall radiation. The surface temperature profile ahead of pyrolysis front is used to qualitatively describe the heat flux received by virgin surface. The results in this paper are essential for better understanding of self induced flame blow off mechanism and upward flame spread under limited distance conditions. [ABSTRACT FROM AUTHOR]

Smart environment sensing and other applications play a more and more important role along with the rapid growth of device-free sensing-based services, and extracting parameters contained in channel state information (CSI) accurately is the basis of these applications. However, antenna arrays in wireless devices are all planar arrays whose antenna spacing does not meet the spatial sampling theorem while the existing parameter estimation methods are almost based on the array satisfying the spatial sampling theorem. In this paper, we propose a parameter estimation algorithm to estimate the signal parameters of angle of arrival (AoA), time of flight (ToF), and Doppler frequency shift (DFS) based on the service antenna array, which does not satisfy the spatial sampling theorem. Firstly, the service antenna array is mapped to a virtual linear array and the array manifold of the virtual linear array is calculated. Secondly, the virtual linear array is applied to estimate the multi-dimensional parameters of the signal. Finally, by calculating the geometric relationship between the service antenna and the virtual linear array, the parameters of the signal incident on the service antenna can be obtained. Therefore, the service antenna can not only use the communication channel for information communication, but also sense the surrounding environment and provide related remote sensing and other wireless sensing application services. Simulation results show that the proposed parameter estimation algorithm can accurately estimate the signal parameters when the array antenna spacing does not meet the spatial sampling theorem. Compared with TWPalo, the proposed algorithm can estimate AoA within 3∘, while the error of ToF and DFS parameter estimation is within 1 ns and 1 m/s. [ABSTRACT FROM AUTHOR]

The energy cost minimization for mission-critical internet-of-things (IoT) in mobile edge computing (MEC) system is investigated in this work. Therein, short data packets are transmitted between the IoT devices and the access points (APs) to reduce transmission latency and prolong the battery life of the IoT devices. The effects of short-packet transmission on the radio resource allocation is explicitly revealed. We mathematically formulate the energy cost minimization problem as a mixed-integer non-linear programming (MINLP) problem, which is difficult to solve in an optimal way. More specifically, the difficulty is essentially derived from the coupling of the binary offloading variables and the resource management among all the IoT devices. For analytical tractability, we decouple the mixed-integer and non-convex optimization problem into two sub-problems, namely, the task offloading decision-making and the resource optimization problems, respectively. It is proved that the resource allocation problem for IoT devices under the fixed offloading strategy is convex. On this basis, an iterative algorithm is designed, whose performance is comparable to the best solution for exhaustive search, and aims to jointly optimize the offloading strategy and resource allocation. Simulation results verify the convergence performance and energy-saving function of the designed joint optimization algorithm. Compared with the extensive baselines under comprehensive parameter settings, the algorithm has better energy-saving effects. [ABSTRACT FROM AUTHOR]

Defensins are the most diverse groups of antimicrobial peptides in invertebrate animals. In ticks, defensins show great potential as targets for tick control, and display future prospect for therapeutic drug development. In the present study, a novel defensin-like gene (Ds-defensin) contributing to the antimicrobial and antioxidant capacity of the tick Dermacentor silvarum was characterized. The full-length of the Ds-defensin gene was 382 bp, which displayed tissue-specific expression and was highly abundant in the salivary glands and carcasses of the adults. It encodes a 71-amino acid defensin-like protein, and the protein precursor is characterized by a 22-amino acid signal peptide and a 34-amino acid mature peptide. The peptide displayed potent activity against most of the tested gram-positive bacteria, including Staphylococcus aureus, S. carnosus and Nocardia asteroides, and one tested gram-negative bacterium, Psychrobacter faecalis. Scanning electron microscopy revealed that the cell wall and surface of treated bacteria became rough and gradually formed pores after a 30-min exposure to the Ds-defensin peptide. Additionally, the peptide also showed significant antioxidant capacity. The above results implied that the defensin-like peptide may play an important role in tick defense and the interaction with microorganisms. [ABSTRACT FROM AUTHOR]

Four-dimensional (4D) printing of shape memory polymer (SMP) imparts time responsive properties to 3D structures. Here, we explore 4D printing of a SMP in the submicron length scale, extending its applications to nanophononics. We report a new SMP photoresist based on Vero Clear achieving print features at a resolution of ~300 nm half pitch using two-photon polymerization lithography (TPL). Prints consisting of grids with size-tunable multi-colours enabled the study of shape memory effects to achieve large visual shifts through nanoscale structure deformation. As the nanostructures are flattened, the colours and printed information become invisible. Remarkably, the shape memory effect recovers the original surface morphology of the nanostructures along with its structural colour within seconds of heating above its glass transition temperature. The high-resolution printing and excellent reversibility in both microtopography and optical properties promises a platform for temperature-sensitive labels, information hiding for anti-counterfeiting, and tunable photonic devices. Four-dimensional (4D) printing of shape memory polymer (SMP) imparts time responsive properties to 3D structures. Here, the authors explore 4D printing of a SMP in the submicron length scale, extending its applications to nanophononics. [ABSTRACT FROM AUTHOR]

We present a simple yet efficient algorithm for recognizing simple quadric primitives (plane, sphere, cylinder, cone) from triangular meshes. Our approach is an improved version of a previous hierarchical clustering algorithm, which performs pairwise clustering of triangle patches from bottom to top. The key contributions of our approach include a strategy for priority and fidelity consideration of the detected primitives, and a scheme for boundary smoothness between adjacent clusters. Experimental results demonstrate that the proposed method produces qualitatively and quantitatively better results than representative state-of-the-art methods on a wide range of test data. [ABSTRACT FROM AUTHOR]

Preventing thermal runaway propagation is critical to improve the fire safety of electric vehicles. Experiments are conducted on the designed battery modules to study the effects of aerogel, liquid cooling plate, and their combination on the prevention mechanism of thermal runaway propagation. The characteristics of temperature, voltage, mass loss, and venting during the thermal runaway propagation process are compared and analyzed. The results indicate that: (1) adding the insulation material of aerogel can postpone the thermal runaway propagation, but may not completely cut-off the propagation process; (2) there is no obvious delay of thermal runaway propagation by adding the liquid cooling plate only, the propagation speed may be accelerated instead; (3) the thermal runaway propagation can be prevented by using aerogel and liquid cooling plate together. The study reminds us that safety design of battery thermal management system should consider the comprehensive heat transfer pathways in order to effectively prevent thermal runaway propagation. [ABSTRACT FROM AUTHOR]

Objective: We aimed to analyze the results of 24-h multichannel intraluminal impedance and pH-monitoring (MII-pH) of the laryngopharynx and esophagus in asymptomatic volunteers. Moreover, we also aimed to gain insight into and establish a baseline for laryngopharyngeal reflux in the healthy population by quantitatively and qualitatively comparing the reflux and pH distribution in both the laryngopharynx and the esophagus. Methods: Healthy volunteers were recruited and observed; they underwent 24-h ambulatory combined MII-pH monitoring. The proximal sensor (pH1) was positioned approximately 1 cm above the upper esophageal sphincter with the aid of a solid-state high-resolution esophageal manometer. Laryngopharyngeal reflux events were detected and characterized by the incidence and property of reflux both in the laryngopharynx and the esophagus. Results: Thirty-eight asymptomatic volunteers who completed all the examinations were included in this study. The median pH detected by the proximal sensor was 6.6 (6.2, 7.0), with an average of 6.58 ± 0.74. A total of 814 laryngopharyngeal reflux events were detected, including 722 (89%) in the upright position and 92 (11%) in the supine position with incidence (0%) in the liquid state, 44 (5%) in the mixture, and 769 (95%) in the gaseous state. Furthermore, 5 incidences (1%) of acid reflux and 809 incidences of non-acid reflux (99%) were noted. A total of 5779 esophageal reflux events were detected, including 5020 (87%) in the upright position, 759 (13%) in the supine position, with 2051 (36%) in the liquid state, 2050 (35%) in the mixed condition, and 1678 (29%) in the gaseous state; adding up to 805 incidences (14%) of acid reflux and 4974 incidences (86%) of non-acid reflux. Conclusion: Non-acid reflux in the upright position is characteristic of laryngopharyngeal reflux. Acid reflux is almost undetectable in healthy subjects. Hence, the diagnostic indicators of gastroesophageal reflux disease are not suitable for laryngopharyngeal reflux disease. [ABSTRACT FROM AUTHOR]

With the rapid development of industrialization and urbanization of coastal regions, eutrophication and metal pollution have caused serious environmental problems in China. To better understand the potential environmental risks associated with nutrients and heavy metals, the surface water was comprehensively investigated in the coastal Bohai Sea. A total of 150 sites were sampled from seven coastal regions, and the concentrations of nutrients (DIN and DIP) and metals (Cd, Pb, Zn, Cu, Cr, As and Hg) in the surface seawater were measured. The results showed that the DIN concentration of about 50% sites exceeded the Grade-I of Seawater Quality Standard of China. Due to high concentrations of DIN, the status of eutrophication was serious in the Bohai Bay and Shuangtaizi Estuary. According to Seawater Quality Standard of China, Pb, Zn, Hg and Cu were the main metal pollutants in the coastal Bohai Sea. There was generally low ecological risk caused by heavy metals, but certain hotspots existed near Shuangtaizi Estuary and Changxingdao Island. [ABSTRACT FROM AUTHOR]

Many low-thermal-conductivity (κL) crystals show intriguing temperature (T) dependence of κL: κL ∝ T−1 (crystal-like) at intermediate temperatures whereas weak T-dependence (glass-like) at high temperatures. It has been in debate whether thermal transport can still be described by phonons at the Ioffe-Regel limit. In this work, we propose that most phonons are still well defined for thermal transport, whereas they carry heat via dual channels: normal phonons described by the Boltzmann transport equation theory, and diffuson-like phonons described by the diffusion theory. Three physics-based criteria are incorporated into first-principles calculations to judge mode-by-mode between the two phonon channels. Case studies on La2Zr2O7 and Tl3VSe4 show that normal phonons dominate low temperatures while diffuson-like phonons dominate high temperatures. Our present dual-phonon theory enlightens the physics of hierarchical phonon transport as approaching the Ioffe-Regel limit and provides a numerical method that should be practically applicable to many materials with vibrational hierarchy. Predicting thermal transport in low-thermal-conductivity (κL) materials is challenging. Here, the authors propose a dual-phonon theory, where normal phonons are treated using the Boltzmann thermal equation and diffuson-like phonons are treated within diffusion theory, yielding robust predictions of κL. [ABSTRACT FROM AUTHOR]

Background: Clarifying the relationship between photosynthesis and irradiance and accurately quantifying photosynthetic performance are of importance to calculate the productivity of phytoplankton, whether in aquatic ecosystems modelling or obtaining more economical production. Results: The photosynthetic performance of seven phytoplankton species was characterized by four typical photosynthesis–irradiance (P–I) response models. However, the differences were found between the returned values to photosynthetic characteristics by different P–I models. The saturation irradiance (Isat) was distinctly underestimated by model 1, and the maximum net photosynthetic rate (Pnmax) was quite distinct from its measured values, due to the asymptotic function of the model. Models 2 and 3 lost some foundation to photosynthetic mechanisms, that the returned Isat showed significant differences with the measured data. Model 4 for higher plants could reproduce the irradiance response trends of photosynthesis well for all phytoplankton species and obtained close values to the measured data, but the fitting curves exhibited some slight deviations under the low intensity of irradiance. Different phytoplankton species showed differences in photosynthetic productivity and characteristics. Platymonas subcordiformis showed larger intrinsic quantum yield (α) and lower Isat and light compensation point (Ic) than Dunaliella salina or Isochrysis galbana. Microcystis sp., especially M. aeruginosa with the largest Pnmax and α among freshwater phytoplankton strains, exhibited more efficient light use efficiency than two species of green algae. Conclusions: The present work will be useful both to describe the behavior of different phytoplankton in a quantitative way as well as to evaluate the flexibility and reusability of P–I models. Meanwhile we believe this research could provide important insight into the structure changes of phytoplankton communities in the aquatic ecosystems. [ABSTRACT FROM AUTHOR]

Features extraction and analysis for human activity recognition (HAR) have been studied for decades in the 5th generation (5G) and beyond the 5th generation (B5G) era. Nowadays, with the extensive use of unmanned aerial vehicles (UAVs) in the civil field, integrating wireless signal receivers on UAVs could be a better choice to receive hearable signals more conveniently. In recent years, the HAR system based on CSI based on WiFi radar has received widespread attention due to its low cost and privacy protection property. However, in the existing CSI-based HAR system, there are two disadvantages: (1) The detection threshold is manually set, which limits its adaptability and immediacy in different wireless environments. (2) A sole classifier is used to complete the recognition, resulting in poor robustness and relatively low recognition accuracy. In this paper, we propose a CSI-based device-free HAR (CDHAR) system with WiFi-sensing radar integrated on UAVs to recognize everyday human activities. Firstly, by using machine learning, CDHAR applies kernel density estimation (KDE) to obtain adaptive detection thresholds to complete the extraction of activity duration. Second, we proposed a random subspace classifier ensemble method for classification, which applies the frequency domain feature instead of the time domain feature, and we choose each kind of feature in the same amount. Finally, we prototype CDHAR on commercial WiFi devices and evaluate its performance in both indoor environment and outdoor environments. The experiment results tell that even if experimental scenario varies, the accuracy of activity durations extraction can reach 98% and 99.60% whether in outdoor or indoor environments. According to the extracted data, the recognition accuracy in outdoor and indoor environments can reach 91.2% and 90.2%, respectively. CDHAR ensures high recognition accuracy while improving the adaptability and instantaneity. [ABSTRACT FROM AUTHOR]

Directional water harvesting is a special ability of flora and fauna in nature. Wettability-patterned surfaces inspired by natural structures have been extensively researched and could be a great potential avenue for easing water shortage. However, preparation strategies for these nature-inspired cases, including UV irradiation with mask technology, femtosecond laser direct writing and chemical treatment, are time-consuming, cost-ineffective and environmentally unfriendly. In this paper, robust and durable superhydrophobic (SHB) glass substrate was prepared by using laser-induced backward transfer technique and fluoroalkylsilane modification. Then wedge-shaped superhydrophilic (SHL) patterns on the SHB surfaces were rapidly constructed by inexpensive and commercially available fibre laser ablation for fog harvesting. This facile, cost-effective and non-corrosive preparation method described herein could be an alternative way to construct SHL–SHB patterns on glass substrate, which could be used for microfluidic devices, droplet manipulation and cell screening. [ABSTRACT FROM AUTHOR]