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A novel strategy involving warm rolling and tempering-annealing was introduced to optimize the strength-ductility balance of Fe-10.2Mn-2.2Al-0.41C-0.6 V (wt. %) steel. The V- and κ-carbide particles produced during the tempering are critical for tailoring the austenite characteristics during the subsequent annealing. Austenite that nucleates on Mn-rich κ-carbides inherit their high Mn content and fine grain size. Quantitative calculations suggest that the pinning effect exerted by the V-carbide particles strongly resists grain boundary motion and recrystallization grain growth, further refining the final microstructure. Moreover, the dual nano-sized particles induce abnormal variations in the grain size and fraction of austenite, influencing the deformation mechanisms. In the absence of deformation twins, the fresh martensite develops into “separating walls” to refine the microstructure and further enhances the work hardening in addition to the complex dislocation mobile. Finally, the tempered-annealed sample demonstrated a simultaneous increase in the yield and tensile strengths from 1166 to 1452 MPa and 1507–1727 MPa, but a slight decrease in the total elongation from 18.6% to 16.8% compared to annealed sample, achieving a good strength-ductility balance.

Efficient multi-resonance thermally activated delayed fluorescence (MR-TADF) materials hold significant potential for applications in organic light-emitting diodes (OLEDs) and ultra-high-definition displays. However, the stringent synthesis conditions and low yields typically associated with these materials pose substantial challenges for their practical applications. In this study, we introduce an innovative strategy that involves peripheral modification with sulfur and selenium atoms for two materials, CFDBNS and CFDBNSe. This approach enables a directed one-shot borylation process, achieving synthesis yields of 66% and 25%, respectively, while also enhancing reverse intersystem crossing rates. Both emitters exhibit ultra-narrowband sky-blue emissions centered around 474 nm, with full width at half maximum (FWHM) values as narrow as 19 nm in dilute toluene solutions, along with high photoluminescence quantum yields of 98% and 99% in doped films, respectively. The OLEDs based on CFDBNS and CFDBNSe display sky-blue emissions with peaks at 476 and 477 nm and exceptionally slender FWHM values of 23 nm. Furthermore, the devices demonstrate remarkable performances, achieving maximum external quantum efficiencies of 24.1% and 27.2%. This work presents a novel and straightforward approach for the incorporation of heavy atoms, facilitating the rapid construction of efficient MR-TADF materials for OLEDs.

Trichogramma, a genus of egg parasitoid wasps, are widely used as biological control agents and serve as model organisms in parasitoid research. Despite their significance, the understanding of RNA interference (RNAi) in Trichogramma remains very limited. We identified RNAi-associated genes by bioinformatic approaches and experimentally assessed the feasibility of gene knockdown via RNAi for gene functional studies, as well as the susceptibility of T. dendrolimi to envionmental RNAi (dsRNAs targeting 12 genes ). We found that Trichogramma genomes contain a complete set of genes in the RNAi pathway and exhibit extensive gene expansion of dsRNase, which may influence RNAi efficiency by degrading dsRNA. We demonstrated successful RNAi through pupal microinjection in T. dendrolimi Matsumura, providing a technical approach for future gene functional studies. In addition, we observed no evidence of susceptibility to environmental RNAi in either T. dendrolimi adults or larvae. This low environmental RNAi sensitivity in Trichogramma could suggest a reduced risk of RNAi-based pest management strategies affecting nontarget Trichogramma populations. Overall, this study presents a technical approach for conducting gene functional studies in Trichogramma and provides a foundation for evaluating the nontarget effects of RNAi-based pest control strategies on Trichogramma.

α-Quaternary amino acids have found application in many biologically relevant compounds and pharmaceuticals. Although there are many methods for the synthesis of α-quaternary amino acids, most of them are mainly realized with the aid of transition metals and complex ligands. We present herein a 2,7-Br-4CzIPN catalyzed regioselective alkylation of azlactones with redox-active esters via radical–radical couplings. Strikingly, this approach is devoid of any metal or additive and shows broad scope and superior sensitive functional group compatibility.

The fruit of Alpinia oxyphyllaMiq is an important food spice in southern China and has been used in the treatment of kidney disorders for centuries. In order to discover the natural products with potent renoprotective activities in A. oxyphyllaand provide some references for its usage, systematic phytochemical studies were carried out and 24 new diverse sesquiterpenoids, including seven guaiane sesquiterpenoids (1–7), 10 eudesmane sesquiterpenoids (9–13, 18, 19, and 21–23), six cadinane sesquiterpenoids (31–35and 38), and an eremophilane sesquiterpenoid (40), along with 24 known analogues were isolated and elucidated by analysis of spectroscopic data and quantum-chemical calculations. Biological evaluation showed that 6 sesquiterpenoids could significantly inhibit the expression of extracellular matrix components, α-SMA in TGF-β1 induced kidney proximal tubular cells (NRK-52e) at low concentrations, and 9 sesquiterpenoids could also downregulate fibronectin and collagen I in a concentration-dependent manner, showing their potential in renal fibrosis. Further action mechanism study displayed that TGF-β1/Smads pathway might be involved in the antifibrotic effects of active sesquiterpenoids 15and 43. These studies suggest that A. oxyphyllamay have a potential to serve as a functional food in preventing renal fibrosis-associated diseases.

In this work, we propose a simple way to predict the diffusion and rheological properties of linear-ring polymer blends (LRB) by taking into account the polymorphic nature of the ring polymer components. In LRB, the ring components are separated by free rings and threaded rings, and their different dynamic behaviors are confirmed with the help of molecular dynamics simulation. A master curve of the LRB was established as a function of the linear chain concentration, the molar mass of linear and ring polymers, and the fraction of free ring polymers. Furthermore, the diffusion coefficient of threaded ring chains and the relaxation modulus of the blend are obtained based on the tube model framework. In our model, the relaxation of the blend is correlated with the polymorphism of the ring components, in which the threaded ring polymers relax through a constraint release hopping dynamics, while the unthreaded ring chains relax as a free ring. The threaded ring also reduces the constraint release effect for linear chains. Our theoretical prediction agrees with both simulation and experimental data with proper parametrization, which can be used to predict the dynamics of linear/ring blends for a wide range of compositions.

Recent experiments proposed that the precipitated second-phase particles, such as L12-Al3Zr and S phase (Al2CuMg) in Al–Zn–Mg–Cu–Zr alloy, can efficiently trap enrichment H atoms, possibly weakening the H-induced damage of corresponding Al alloy. However, the change of mechanical properties of these precipitates with trapped H atom could not be explored experimentally. Here, taking intermetallic L12-Al3Zr as example, we performed a theoretical prediction to investigate the effect of trapped H on the mechanical properties of L12-Al3Zr. The results showed that although Al3ZrH compound with H located the at the geometric center is energetic and elastic stable, the lattice parameter of L12-Al3Zr seems to be expanded. The permeated H contributes to improve the hardness, brittleness and elastic anisotropy of L12-Al3Zr. In addition, we used a special method to obtain the numerical value of each (100) non-stoichiometric surface for both L12-Al3Zr and Al3ZrH compounds, providing a valuable supplement in calculating the surface energy of the non-stoichiometric surface for cubic structure.

Monophasic Al50Ni50ribbons were fabricated by melt spinning at circumferential speeds (Sc) of 21 and 42 m/s, and subsequently annealed at various temperatures. The microstructure and corrosion behavior of ribbons were studied through various experimental methods. With increasing Sc, the as-spun and annealed ribbons at 42 m/s show a higher (100) crystal orientation factor F(100), a lower barrier to recrystallization and a higher total film resistance than the counterparts with 21 m/s. The as-spun ribbon at 42 m/s demonstrated a denser and more stable Al2O3passive film compared to the as-spun and annealed ribbons at 21 m/s. This improvement in passive film can be further enhanced by 700 °C annealing. Therefore, the corrosion resistance of AlNi ribbons can be improved by increasing Scand additional annealing at an appropriate temperature.

In recent years, under the background of low carbonization and industrial intelligence, with the rise of new energy sources such as wind energy and solar energy, rare earth permanent magnets have begun to be widely used in generators of these new energy sources. From the perspective of green and sustainable development, permanent magnet motor can reduce energy loss and meet the requirements of sustainable development through the reasonable selection and utilization of permanent magnet materials, the design of motor structures, and advanced transmission control technology. In this paper, a 225 kW/34,000 rpm high speed permanent magnet motor (HSPMSM) is designed. Firstly, the electromagnetic design of the motor is carried out, and the finite element model is established. The rotor temperature rise under different materials is analyzed by comparing the electromagnetic characteristics and loss of different permanent magnet materials and using the principle of electrothermal coupling. Combined with the thermal performance of the material, the advantages of rare earth permanent magnet are analyzed, and SmCo permanent magnet material is selected to be more suitable for the motor. Due to the motor's high speed and high frequency harmonic rate, an improved proportional resonant algorithm based on active disturbance rejection is studied and analyzed. Compared with the traditional PI control, the algorithm further reduces the harmonic content of the motor's stator current while improving the motor's running state, thereby reducing the overall loss of the motor. The prototype and experimental platform are made, and the experimental results verify the correctness of the simulation analysis.

To optimize the anti-interference performance and dynamic response ability of permanent magnet linear synchronous motor (PMLSM) and enhance the overall control performance of the system, the novel nonsingular fast terminal sliding mode controller (NFTSMC) based on disturbance compensation is proposed in this design. To enhance the response speed and stability of the controller, this design introduces the system state variable into the exponential reaching law to make the controller adaptively adjust with the change of the system state, which can reduce the chattering of the system and have a faster response speed. The extended sliding mode disturbance observer is designed to estimate the interference factors in the system, and the controller is feedforward compensated to further improve the anti-interference ability of the PMLSM system. Meanwhile, the control strategy is proved by the Lyapunov stability theory. Simulation and experiments show that the proposed control strategy has better dynamic response ability and anti-interference ability than the traditional NFTSMC.

In this study, 5 species of TrichogrammaWestwood were evaluated for the biological control of Spodoptera frugiperda(JE Smith), concerning the physical characteristics of female Trichogramma. The results showed that Trichogramma chilonisIshii, Trichogramma dendrolimiMatsumura, and Trichogramma ostriniaePang et Chen exhibited high parasitism rates, emergence rates, and offspring numbers, with the highest values observed for T. ostriniae. The ovipositor length of Trichogramma japonicumAshmead and T. dendrolimiwere longer than those of other species, and the hind tibia length was the shortest in Trichogramma cacoeciaeMarchal. We further evaluated relationships between the parasitism ability of Trichogrammaand various morphological indexes based on Spearman’s rank correlation coefficients. A positive correlation was found between the parasitism rate and hind tibia length of T. cacoeciae. In T. dendrolimi, the parasitism rate was negatively correlated with ovipositor width and positively correlated with the length-width ratio of the ovipositor. A significant positive correlation was observed between the proportion of female offspring and the mother’s ovipositor length in T. japonicum. However, there were no significant correlations between morphological indexes and indexes of parasitism in T. ostriniae. Overall, the parasitic abilities of T. chilonison S. frugiperdaeggs were significantly correlated with the morphology of the female ovipositors.Graphical Abstract

In this work, we investigate the performance of a reconfigurable intelligent surface-assisted full-duplex relaying system with imperfect channel state information and hardware impairments. More specifically, we derive the analytical expressions for the outage probability, average bit error rate, and average capacity. To provide more insightful results, the corresponding asymptotic analysis is also performed. Finally, all the analytical results are verified by Monte Carlo simulations and a performance floor phenomenon is observed.

High strength steels exhibit superior mechanical properties due to the unique microstructure, which successfully solves the drawback of the inevitable strength-toughness trade-off that occurs in traditional alloys. Here we investigated the effect of matrix and precipitates on mechanical properties of Cr–Ni–Mo–V/Nb steel after water quenching and tempering (150–500 °C). The results showed that the microstructure of the present steel is noticeably tuned by changing the tempering temperature. An excellent combination of strength (a yield strength of 1308 MPa with a total elongation of 8.2%) and toughness (Charpy V-notch impact toughness of 40.5 J/cm2) is obtained upon tempering at 200 °C. This is attributed to the lath martensite containing high dislocation density, the martensite-twin substructure, and the strengthening effects of the precipitated needle-like ε-carbides and spherical VC particles. The acicular ε-carbides are replaced by the rod-shaped Fe3C at the tempering temperature of 350 °C, resulting in the remarkable deterioration in strength, hardness, and elongation. Spheroidized carbides formed at a tempering temperature of 500 °C are beneficial to the enhancement of the elongation and toughness, but the strength decreases due to the matrix softening caused by the recovery of dislocation.

The assumption of zero strain at both ends of the sensing layer for flexible sensors results in inaccurate strain transfer assessment because of the traction from the coating to the sensing layer. This article proposed a new strain transfer model considering the coating effect to accurately characterize the actual strain of the sensing layer. First, a five-layered strain transfer model is established based on shear lag theory, and the strain functions for the sensing layer and coating are conducted to react with the actual boundary conditions. Next, the strain transfer coefficient of the coating effect is derived by solving the functions with the consideration of continuity conditions at the ends of the sensing layer. Results of numerical simulations and experiments demonstrate that the proposed model predicts a more accurate strain compared with the existing model, and the increase in coating length will reduce the strain transfer loss in the flexible sensor. This allows for the calibration of the measured strain from flexible sensors based on the strain transfer coefficient.

Despite tremendous efforts in the past decades, relationships among main avian lineages remain heavily debated without a clear resolution. Discrepancies have been attributed to diversity of species sampled, phylogenetic method and the choice of genomic regions1–3. Here we address these issues by analysing the genomes of 363 bird species4(218 taxonomic families, 92% of total). Using intergenic regions and coalescent methods, we present a well-supported tree but also a marked degree of discordance. The tree confirms that Neoaves experienced rapid radiation at or near the Cretaceous–Palaeogene boundary. Sufficient loci rather than extensive taxon sampling were more effective in resolving difficult nodes. Remaining recalcitrant nodes involve species that are a challenge to model due to either extreme DNA composition, variable substitution rates, incomplete lineage sorting or complex evolutionary events such as ancient hybridization. Assessment of the effects of different genomic partitions showed high heterogeneity across the genome. We discovered sharp increases in effective population size, substitution rates and relative brain size following the Cretaceous–Palaeogene extinction event, supporting the hypothesis that emerging ecological opportunities catalysed the diversification of modern birds. The resulting phylogenetic estimate offers fresh insights into the rapid radiation of modern birds and provides a taxon-rich backbone tree for future comparative studies.

Orange dark tea (ODT) is widely produced in China, but the quality of traditional sunlight-dried ODT is not satisfactory, thus limiting its industrial production. This study compared the effects of traditional sunlight drying and current hot air drying on ODT quality. Sensory evaluation showed that hot air-dried orange dark tea (HAD) had better peel-tea integration and higher sensory score. Compared with sunlight-dried ODT (SLD), HAD exhibited higher contents of polyphenols, flavonoids, hesperidin and limonin. Gas chromatography-mass spectrometry (GC–MS) analysis of volatile components in the two ODTs identified a total of 102 aroma components, where 22 differential metabolites and 4 key aroma substances (linalool, limonene, β-myrcene and sabinene) were screened. Bioactivity analysis showed that HAD had better inhibitory effect against α-glucosidase and α-amylase activity, indicating superior overall quality. Further analysis of the effect of drying temperatures on ODTs quality exhibited that low temperature drying at 40 to 50 °C endowed ODT with lower bitterness and astringency, richer polyphenols, flavonoids, hesperidin, and free amino acids, also indicating better comprehensive quality. All the results indicate that hot air drying outperforms sunlight drying in improving ODT quality. This study provides a basis for process optimization of ODT.

In this letter, we investigate an active reconfigurable intelligent surface (RIS) and non-orthogonal multiple access (NOMA)-aided covert communication system with hardware impairments, where a base station conducts NOMA downlink transmissions to a covert user and a public user. More specifically, we derive the analytic expressions for the outage probability (OP), the detection error probability (DEP), and optimal detection thresholds. Then, we study the influence of detection threshold, RIS deployment location, and power distribution factor on the covert performance. Compared to the passive RIS system with the same total power budget, numerical results show that the active RIS system achieves better covert performance and effectively overcomes the double path-loss attenuation.

An antenna-in-package (AiP) of $4\,\, {}\times {}4$ elements with dual-polarized radiations for high-power radiation at a 28 GHz band was designed and fabricated by low-temperature co-fired ceramic (LTCC) for fifth-generation (5G) applications. The design starts with selecting cross-dipole elements to ensure good polarization purity. The l/4 separation from a ground plane is achieved by considering a proper combination of multilayered substrates’ thicknesses and their dielectric constant, where the feedings are probed by coaxial-type vias from the bottom. The dipole arms’ shapes are optimally tuned to achieve broadband reflection coefficients. This AiP has the advantage of dual-polarizations along +/−45° to avoid harmful interferences from metal-supporting structures, reasonable inter port isolations, and low cross-polarization levels (XPLs). The AiP has a compact profile of $28\,\, {}\times {}28$ mm2. The interport isolation between the polarization excitation ports is larger than 33 dB from HFSS full-wave simulations. The elements’ bandwidth is larger than 6 GHz from the full-wave simulation and broader than 4 GHz from measurements over the antenna prototype. The array has a bandwidth larger than 6 GHz from measurement with a maximum gain of 16.6 dBi and a sidelobe level (SLL) of 13.3 dB, validating the design concept.

Catalyst innovation lies at the heart of transition-metal-catalyzed reaction development. In this article, we have explored the C(sp2)—H alkenylation activity with novel spirocyclic N-heterocyclic carbene (NHC)-based cyclometalated ruthenium pincer catalyst system, SNRu-X. After screening catalyst and condition, a high valent Ru(IV) dioxide (X = O2) species has demonstrated superior reactivity in the catalytic alkenylation of aromatic and olefinic C-H bonds with unactivated alkenyl bromides and triflates. This reaction has achieved the easy construction of a wide range of (hetero)aromatic alkenes and dienes, in good to excellent yields with exclusive selectivity. Preliminary mechanistic studies indicate that this reaction may proceed through a single electron transfer (SET) triggered oxidative addition, by doing so, providing valuable complementary to classical alke-nylation reactions that are dependent on activated alkenyl precursors.

The spatial information provided by 3-D object detection is critical for autonomous driving. Although visual-based object detection has made significant progress in 2-D/3-D in recent years, nonvisual sensors such as 3-D light detection and ranging (LiDAR) still have inherent advantages in the accuracy (ACC) of object localization. However, the challenge still lies in the interpretability of the sparse point clouds it generates and the difficulty of being manually annotated. In this article, we propose an online transfer learning framework based on multimodal sensor systems for 3-D object detection of urban road participants including pedestrians, cyclists, and cars. The framework aims to automatically and efficiently transfer object detection capabilities from 2-D monocular camera to 3-D LiDAR through a multitarget tracker-based pipeline, enabling knowledge transfer between sensors of different modalities. Furthermore, online random forest (ORF), an inherently fast and multiclass learning method, is innovatively integrated into our system. Experiments on two very different datasets, including KITTI and Waymo, demonstrate that the proposed framework not only rapidly builds 3-D detection capabilities about road participants in a single dataset but also maintains this capability across datasets. This reveals that the proposed framework is particularly suitable for in situ deployment of unmanned vehicles and can also solve the problem of insufficient generalization ability of current offline-trained detectors.

Adding alloying elements is always considered as an effective method to enhance the resistance against hydrogen embrittlement in steels. Nb and V were added into 22MnB5 hot stamping steel, and then their influences on hydrogen permeation of 22MnB5 steel suffering from corrosion in 3.5% NaCl aqueous solution were investigated. The results showed that the addition of Nb/V could reduce the hydrogen permeation content due to solution corrosion. Electrochemical techniques including electrochemical impedance spectroscopy and overpotential stepping hydrogen permeation test confirmed that compared to the original 22MnB5 steel, 22MnB5-Nb/V steel owned a higher corrosion resistance and a higher hydrogen diffusion resistance. Furthermore, it was confirmed that Nb–V-alloyed 22MnB5 steel showed higher resistance against hydrogen embrittlement than the Nb–V-free counterpart, which should be related to the presentence of nanoscaled Nb/V-containing precipitates as the irreversible trapping sites for hydrogen detected by thermal desorption spectroscopy. Finally, the lattice diffusion coefficient of hydrogen DLwas determined in steels with and without Nb and V.

•Epstein-Barr virus (EBV) was reactivated in a high propotion of severe fever with thrombocytopenia syndrome (SFTSV)-infected patients;•In EBV reactivated SFTS patients serum albumin was significantly lower;•In EBV reactivated SFTS patients the urine red blood cells were significantly higher.

Light detection and ranging (LiDAR) limitations in adverse weather (e.g., rain, fog, and snow) prevent adopting high-level autonomous vehicles in all weather conditions. Furthermore, collecting and annotating these sparse point clouds in adverse weather is often cumbersome, inefficient, and expensive. In this article, we propose a data-driven approach to statistically model the performance of a popular near-infrared (NIR) time-of-flight (ToF) LiDAR in fog, with noisy point clouds collected in a well-controlled artificial fog chamber. Given manually defined visibility describing the levels of fog, our models can directly forecast a probability distribution of a laser’s noisy range measurement. Moreover, the real road data collected in clear weather is utilized to produce auto-labeled noisy point clouds using a LiDAR performance simulator, which is then used to train a semantic segmentation network to recognize point cloud noise in the real world in adverse weather. Qualitative and quantitative experimental results verify the applicability of our LiDAR performance models in fog and show how our Sim2Real strategy of the denoising algorithm can be applied to noisy point clouds under various weather conditions. The developed robot operating system (ROS) packages are publicly available at: https://github.com/cavayangtao/lanoise_pp.

Charge transport in conjugated polymers is affected not only by the static structure but also the dynamics of backbone segments. A series of regiorandom poly(3-alkylthiophenes) (P3ATs) with 6–12 alkyl carbons per side chain are studied by the all-atom molecular dynamics simulations. By investigating the effect of temperature and side chain length on the static structure, we identify that the peak of neutron scattering at q∼ 0.42 Å–1is from the backbone’s edge-to-edge packing along the side-chain direction and shifts to the lower qwith the increasing side chain length. The peak at q∼ 1.35 Å–1is contributed by both the intrachain side chain-side chain correlation and the interchain correlation on the face-to-face stacking direction. In addition, the increase in side chain length can lead to faster backbone dynamics. The farther the carbon atom is from the backbone, the faster it moves. Based on the dynamic analysis, the faster motion of the backbone is mainly attributed to the last three atoms close to the end of the alkyl side chain, which have distinct dynamics compared with the carbons in the inner part of side chains close to the rigid backbone.

Cp*Rh(III)-catalyzed nitro-directed C–H alkylation/alkenylation of nitroarenes has been reported for the first time. This protocol is associated with the features of high efficiency, broad substrate scope, and good functional group compatibility. Additionally, gram-scale experiments and synthetic applications proved the practicability of the method. Moreover, preliminary mechanistic investigations consistently revealed C–H bond cleavage as the rate-limiting step.

An efficient aminofluorosulfonylation strategy was developed for the synthesis of various pyrazoline-functionalized aliphatic sulfonyl fluorides using β,γ-unsaturated hydrazones with sulfur dioxide and NFSI as the starting materials under mild conditions. The sulfonyl fluoride products could be successfully transformed into the corresponding sulfonate esters and amides via the sulfur(VI) fluoride exchange (SuFEx) click reactions. Preliminary mechanistic investigations demonstrate that the reaction operates through a radical cyclization/SO2insertion/fluorination cascade process.

In this paper, changes in entropy generation, entropy flow and damage are discussed under cyclic loading for AZ31 magnesium alloy. Results show that the entropy generation increases sharply at the beginning of the cycle, decreases to a certain extent and remains stable. The evolution law of entropy flow is similar to that of temperature in the magnesium alloy fatigue process. Fatigue damage rises exponentially and increases rapidly after the damage reaches 0.3. The relationship between the fatigue fracture entropy model and cycle times, which can predict the fatigue life well, is established. The relationship between the stable value of entropy generation and cyclic loading is also established. The fatigue limit is 102.25 MPa, and the error is 6.8%.

In this paper, changes in entropy generation, entropy flow and damage are discussed under cyclic loading for AZ31 magnesium alloy. Results show that the entropy generation increases sharply at the beginning of the cycle, decreases to a certain extent and remains stable. The evolution law of entropy flow is similar to that of temperature in the magnesium alloy fatigue process. Fatigue damage rises exponentially and increases rapidly after the damage reaches 0.3. The relationship between the fatigue fracture entropy model and cycle times, which can predict the fatigue life well, is established. The relationship between the stable value of entropy generation and cyclic loading is also established. The fatigue limit is 102.25?MPa, and the error is 6.8%.

Automated guided vehicle (AGV) is widely used in transportation and distribution of materials. In the development of multi-AGV systems, how to handle deadlocks is a core issue. Most existing researches focus on open systems. Thus those results are not applicable in real-world systems. A few works have paid attention to closed systems recently, but the results are not flexible and generic enough. Therefore, an improved deadlock avoidance algorithm in closed guide-path system is proposed in this paper. The proposed algorithm is divided into an offline stage and an online stage. At the offline stage, the guide-path graph is processed to obtain useful information for the online stage. At the online stage, the algorithm assesses the safety of each resource allocation to ensure a deadlock-free operation. The computational complexity of the algorithm is shown to be $O(|E|)$ , where $E$ is the set of the edges in the guide-path graph. Based on the algorithm, an overall control strategy is also developed, and then implemented and tested in real systems. It is also compared with Banker’s algorithm and its variants, the results of which show that the proposed algorithm has a better performance. Note to Practitioners—Deadlock is a core issue in guide-path based multi-AGV systems. Once deadlock occurs, the whole system will collapse. This problem is more serious in closed systems, which is paid less attention to in literature. Current deadlock solutions are either too restrictive, resulting in inefficient resource utilization and poor flexibility, or computationally intensive and thus are unable to scale to large systems. To solve this problem, an improved deadlock avoidance algorithm with polynomial computational complexity is proposed in this paper, and it is more flexible than the Banker’s algorithm and its variants. Furthermore, an overall control framework (i.e., including task assignment, path planning and real-time scheduling) is developed based on the deadlock avoidance algorithm, which keeps persistent operation of the considered system while still guaranteeing deadlock-free. However, in this overall control framework, the choice of path is not optimized with respect to travel distance and makespan, which is the direction of future research.

Amines, especially those with multi-nitrogen moieties, are widespread in natural products and biologically active compounds. Thus, the development of direct and efficient methods to introduce multiple nitrogen-containing fragments into compounds in one step is highly desirable yet challenging. Herein, we report an NIS-promoted selective amino-diazidation and amino-iodoazidation of O-homoallyl benzimidates with NaN3. By using this protocol, a variety of vicinal diazido-substituted 1,3-oxazines and vicinal iodoazido-substituted 1,3-oxazines were directly synthesized in a controllable manner. Preliminary mechanistic investigations revealed that the reaction operates through a NIS-promoted four-step cascade process. The developed method has the merits of metal-free, excellent functional group compatibility, simple operation, and mild conditions.

It remains unclear whether alterations in brain function occur in the early stage of pediatric type 1 diabetes mellitus(T1DM). We aimed to examine changes in spontaneous brain activity and functional connectivity (FC) in children with T1DM using resting-state functional magnetic resonance imaging (rs-fMRI), and to pinpoint potential links between neural changes and cognitive performance.

Fresh-cut cantaloupe is very perishable due to the mechanical damage and susceptibility to microorganism infections, which limit their shelf life. Cantaloupe is a popular fruit with high moisture content and nutritional value. This study aimed to enhance fresh-cut cantaloupe quality and extend the shelf life by employing soy protein isolates (SPI) coating solutions containing calcium lactate (CaL) and λ-aminobutyric acid (GABA). Cold plasma (CP) was used to augment the antioxidant and antimicrobial activities of the coatings. The coatings were meticulously characterized, and their impact on fresh-cut cantaloupe was assessed through physicochemical and microbiological parameters. The incorporation of CaL and GABA and the CP treatment heightened the antioxidant activity of the SPI coating, resulting in a substantial increase in DPPH and ABTS free radical scavenging activities by 58% and 30%, respectively. Application of the composite coating included a noteworthy 24% reduction in water loss on fresh-cut cantaloupe, maintaining color stability and total soluble solids content. Moreover, the treatment of composite coating effectively controlled microbial growth, ensuring fresh-cut cantaloupe remained in an edible state at the conclusion of the storage period. The coating treatment has extended the shelf life of fresh-cut cantaloupe from 6 d to 10 d at 0 °C. In conclusion, the CP-treated bioactive coating containing CaL and GABA prolonged the shelf life, enhanced nutritional value, and preserved the microbial quality attributes of fresh-cut cantaloupe.

Based on the complexity of material damage and fracture behavior, the tensile deformation process of AZ31B magnesium alloy is characterized by infrared thermography (IR) and acoustic emission (AE) these two non-destructive technologies, and using in-situ EBSD technology to explore microstructure evolution under different tensile strains simultaneously. The results show that in the process of tensile deformation, the degree of strain hardening increases continuously with the deformation, and the deformation mechanism of the material changes from basal slip to pyramidal slip and {10–12} tensile twinning. The tensile deformation stage presents different signal characteristics. Using fracture mechanics and the energy release law of materials, combined with temperature and AE signal fluctuations, the transformation of the deformation mechanism, the degree of work hardening, and the dangerous zone during the entire tensile process can be effectively captured.