A single-stage accelerator mass spectrometer (GXNU-AMS) developed for radiocarbon and tritium measurements was installed and commissioned at Guangxi Normal University in 2017. After several years of operational and methodological upgrades, its performance has been continuously improved and applied in multidisciplinary fields. Currently, the measurement sensitivity for radiocarbon and tritium is 14C/12C ∼ (3.14 ± 0.05) ×10–15 and 3H/1H ∼ (1.23 ± 0.17)×10–16, respectively, and the measurement accuracy is ∼0.6%, which can meet the measurement requirements in the nuclear, earth, environmental and life science fields. This study presents the performance characteristics of GXNU-AMS and several interesting application studies.

This paper studies the sustainability of plastrons on superhydrophobic (SHPo) surfaces made of longitudinal micro-trenches covered by nano-grass with the main interest on hydrodynamic friction drag reduction in high-speed flows of open water, which represent the operating conditions of common watercraft. After revising the shear-driven drainage model to address the air diffusion for SHPo surfaces, the existing theories are combined to reveal the trends of how the immersion depth, air saturation level and shear stress affect the maximum attainable plastron length. Deviations from the theories by the dynamic effect at the two ends of the trench, the interfacial contaminations and turbulent fluctuation are also discussed. A combinatorial series of well-defined SHPo trench surfaces (4 cm × 7 cm in size with varying trench widths, depths, lengths and roughnesses) is microfabricated and attached underneath a 4 m long motorboat on seawater in turbulent flows up to 7.2 m s−1 (shear rate ∼83 000 s−1 and friction Reynolds number ∼5500). Because the plastron can provide a substantial slip only while its air–water interfaces are pinned (or only slightly depinned) at the trench top, two underwater cameras are employed to differentiate the pinned (and slightly depinned) interfaces from the depinned (and no) interfaces. In addition to achieving pinned plastrons on 6 cm long trenches aligned to high-speed flows in open water, the experimental results corroborate the theoretical estimations, supporting the design of SHPo surfaces for field applications.

Shortawn foxtail (Alopecurus aequalis Sobol.) is an obligate wetland plant that is widely distributed throughout Europe, temperate Asia, and North America. In China, it is widespread in the middle and lower reaches of the Yangtze River as a noxious weed in winter cropping fields with a rice (Oryza sativa L.) rotation. The acetolactate synthase (ALS)-inhibiting herbicide mesosulfuron-methyl has been widely used to control annual grass and broadleaf weeds, including A. aequalis, in wheat (Triticum aestivum L.) fields, leading to the selection of herbicide-resistant weeds. In this study, an A. aequalis population, AHFT-4, that survived mesosulfuron-methyl at the field-recommended rate (9 g ai ha−1) was collected in Anhui Province. Single-dose testing confirmed that the suspected resistant AHFT-4 had evolved resistance to mesosulfuron-methyl. Target gene sequencing revealed a resistance mutation of Pro-197-Ala in ALS1 of the resistant plants, and a derived cleaved amplified polymorphic sequence marker was developed to specifically detect the mutation. A relative expression assay showed no significant difference in ALS expression between AHFT-4 and a susceptible population without or with mesosulfuron-methyl treatment. Whole-plant dose–response bioassays indicated that AHFT-4 had evolved broad-spectrum cross-resistance to ALS-inhibiting herbicides of all five chemical families tested, with GR50 resistance index (RI) values ranging from 21 to 206. However, it remained susceptible to the photosystem II inhibitor isoproturon. Pretreatment with the cytochrome P450 inhibitor malathion or the glutathione S-transferase inhibitor 4-chloro-7-nitrobenzoxadiazole had no significant effects on the resistance of AHFT-4 to mesosulfuron-methyl. To our knowledge, this study reports for the first time the ALS gene Pro-197-Ala substitution conferring broad-spectrum cross-resistance to ALS-inhibiting herbicides in A. aequalis.

Although the well-known Upper Jurassic Morrison Formation has yielded abundant fossil plants for nearly a century, relatively little is known about fossil fungi and their ecological relationships to the Morrison flora. The first mention of fungal decay in fossil wood was briefly made over three decades ago, and since then, a few more reports of fungal decay associated with Morrison plants have been published. However, up to now, detailed data on the fossil fungi themselves have not been given from the Morrison Formation. Here we describe in detail well-preserved fossil mycelia in a silicified log of Xenoxylon utahense Xie et Gee, 2021 from the Upper Jurassic Morrison Formation at Miners Draw, Blue Mountain, near Vernal in northeastern Utah, USA. The fungal hyphae are variable in form, ranging from straight to slightly curved to highly coiled to tubular; they measure ~1.53 μm in diameter and possess clamp connections, septa, and occasional bifurcations. The occurrence of clamp connections typical of living Basidiomycota indicates a taxonomic affinity to this division of fungi. On the basis of the patterns of wood decay in the Xenoxylon log, the fossil fungi are interpreted here as pertaining to saprotrophic, white-rot wood fungi. These fossil mycelia represent a new record of ancient Basidiomycota from the Upper Jurassic Morrison Formation and provide further evidence for plant–fungus interactions in Jurassic terrestrial ecosystems.

Achieving an all-fiber ultra-fast system with above kW average power and mJ pulse energy is extremely challenging. This paper demonstrated a picosecond monolithic master oscillator power amplifier system at a 25 MHz repetition frequency with an average power of approximately 1.2 kW, a pulse energy of approximately 48 μJ and a peak power of approximately 0.45 MW. The nonlinear effects were suppressed by adopting a dispersion stretched seed pulse (with a narrow linewidth of 0.052 nm) and a multi-mode master amplifier with an extra-large mode area; then an ultimate narrow bandwidth of 1.32 nm and a moderately broadened pulse of approximately 107 ps were achieved. Meanwhile, the great spatio-temporal stability was verified experimentally, and no sign of transverse mode instability appeared even at the maximum output power. The system has shown great power and energy capability with a sacrificed beam propagation product of 5.28 mm $\cdot$ mrad. In addition, further scaling of the peak power and pulse energy can be achieved by employing a lower repetition and a conventional compressor.

The grey wolf optimizer (GWO) as a new intelligent optimization algorithm has been successfully applied in many fields because of its simple structure, few adjustment parameters and easy implementation. This paper mainly aims at the defects of GWO in path planning application, such as easily falling into local optimization, poor convergence and poor accuracy, and turn point grey wolf optimization (TPGWO) algorithm is proposed. First, the idea of cross-mutation and roulette is used to increase the initial population of GWO and improve the search range. At the same time, the convergence factor function is improved to become a nonlinear update. In the early stage, the search range is expanded, and in the later stage, the convergence speed is increased, while the parameters in the convergence factor function can be adjusted according to the number of obstacles and the map area to change the turning point of the function to improve the convergence speed and accuracy of the algorithm. The turning times and turning angles of the obtained path are added to the fitness function as penalty values to improve the path accuracy. The optimization test is carried out through 16 test functions, and the test results prove the convergence and robustness of TPGWO algorithm. Finally, the TPGWO algorithm is applied to the path planning of patrol robot for simulation experiments. Compared with the GWO algorithm and Particle Swarm Optimization, the simulation results show that the TPGWO algorithm has better convergence, stability and accuracy in the path planning of patrol robot.

We present a high-energy, hundred-picosecond (ps) pulsed mid-ultraviolet solid-state laser at 266 nm by a direct second harmonic generation (SHG) in a barium borate (BaB2O4, BBO) nonlinear crystal. The green pump source is a 710 mJ, 330 ps pulsed laser at a wavelength of 532 nm with a repetition rate of 1 Hz. Under a green pump energy of 710 mJ, a maximum output energy of 253.3 mJ at 266 nm is achieved with 250 ps pulse duration resulting in a peak power of more than 1 GW, corresponding to an SHG conversion efficiency of 35.7% from 532 to 266 nm. The experimental data were well consistent with the theoretical prediction. To the best of our knowledge, this laser exhibits both the highest output energy and highest peak power ever achieved in a hundred-ps/ps regime at 266 nm for BBO-SHG.

Understanding user perceptions of interacting with the virtual world is one of the research focuses in recent years, given the rapid proliferation of virtual reality (VR) and driven to establish the metaverse. Users can generate a familiar connection between their bodies and the virtual world by being embodied in virtual hands, and hand representations can induce users’ embodiment in VR. The sense of embodiment represents the cognitive awareness of one's manifestation and includes three subcomponents: the sense of body ownership, agency and self-location. There is insufficient evidence in the literature about the effects of hand designs on the embodiment, especially based on studying its three subcomponents. This study investigates how virtual hand designs with five realism levels influence the three subcomponents of embodiment in VR. This research employs a self-report questionnaire commonly used in the literature to assess embodiment and evaluates agency and self-location by introducing implicit methods (intentional binding and proprioceptive measurement) derived from psychology. Besides, the objective data of eye tracking is used to explore the connection between embodiment and hand designs, and classifying participants’ eye tracking data to help analyze the link between embodiment and user attention. Overall, this research makes a major contribution through a systematic exploration of users’ embodied experience in VR and offers important evidence of the effects of virtual hand designs on body ownership, agency, and self-location, respectively. In addition, this study provides a valuable reference for further investigation of embodiment through implicit and objective methods, and practical design recommendations for virtual hand design in VR applications.

Adopting a cross-language long-term repetition-priming paradigm, the current study systematically investigated number representation in Tibetan–Mandarin bilinguals. The study focused on three types of numerals: Arabic digits, Tibetan numerals, and Mandarin numerals. Experiment 1 examined lexical representation; participants performed a lexical decision task in the cross-language repetition-priming paradigm. Experiment 2 used a parity judgment task to examine conceptual representation. In both experiments, if the presentation of the numerals during the learning phase facilitated responses to their translation equivalents in the testing phase, it would indicate that they activate each other (i.e., a shared representation). Results showed that the presentation of Tibetan or Mandarin numerals did not facilitate subsequent responses to the Arabic digit equivalent. No cross-language repetition-priming effect between Tibetan and Mandarin numerals was found in the lexical decision task, indicating that Arabic digits, Tibetan number words, and Mandarin number words are stored separately at the lexical level. At the conceptual level, the results were quite the opposite, suggesting that these three types of numerals share a common representation. To sum up, the results imply that bilinguals’ number representation is similar to bilinguals’ language representation, providing a better understanding of number representation in bilinguals from a linguistic perspective.

A new approach to target development for laboratory astrophysics experiments at high-power laser facilities is presented. With the dawn of high-power lasers, laboratory astrophysics has emerged as a field, bringing insight into physical processes in astrophysical objects, such as the formation of stars. An important factor for success in these experiments is targetry. To date, targets have mainly relied on expensive and challenging microfabrication methods. The design presented incorporates replaceable machined parts that assemble into a structure that defines the experimental geometry. This can make targets cheaper and faster to manufacture, while maintaining robustness and reproducibility. The platform is intended for experiments on plasma flows, but it is flexible and may be adapted to the constraints of other experimental setups. Examples of targets used in experimental campaigns are shown, including a design for insertion in a high magnetic field coil. Experimental results are included, demonstrating the performance of the targets.

The North China Plain is an important summer maize/winter wheat rotation area. However, over the years, continued intensive tillage has destroyed the soil aggregate accelerating the mineralization and decomposition of soil organic carbon (SOC), which plays an important role in soil quality, as increased organic carbon storage improves soil fertility and crop yields. Thus, the objective of this study was to explore the comprehensive impact of tillage methods on soil aggregates, aggregate-associated SOC, and carbon sequestration capacity under a regime of straw return. In 2002, we started a 14-year long-term tillage experiment; then in 2016–2017, we tested the following tillage methods, zero tillage (ZT), rotary tillage (RT), subsoiling (SS), and conventional tillage (CT). The results showed that in the 0–10 cm soil layer, tillage methods significantly reduced the proportion of aggregates in the order of 2–0.25 > 5–2 > 0.25–0.053 mm. Additionally, conservation tillage (i.e., SS and ZT) significantly increased the percentage of macroaggregates (0–40 cm) and their SOC content, compared to CT. Additionally, the contribution rate of macroaggregates to SOC was 17.2% and 30.6% higher under SS and ZT than under CT, respectively. Conservation tillage methods improved the carbon sequestration capacity of soil aggregates. Our study provides a theoretical basis for the development of more suitable tillage methods. Furthermore, long-term conservation tillage seemingly protected large aggregates and, SOC, whereby carbon sequestration was enhanced and soil carbon emissions were effectively reduced.

Relations between China and Latin America date back hundreds of years and have intensified since the founding of the People's Republic of China. Recognizing that meaningful relations with Latin America require an understanding of that varied region, China has established appropriate study and research programs. This essay on current Latin American programs in the People's Republic of China will report on research organizations, research interests of Chinese scholars, and current trends within Latin American studies. The double objectives are to describe China's interest in Latin America and to establish closer contacts between Latin Americanists in China and the United States.