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Photocatalytic sterilization technology is a strategy that is environmentally friendly for killing drug-resistant bacteria using solar energy. The role of reactive oxygen species (ROS) required for sterilization depends on the charge separation properties of the photocatalyst. Therefore, we modified the photocatalytic performance of CuIn5S8 by fabricating S-vacancies based on the work function (Φ) theory. The spin state density calculations show that S-vacancies lead to spin polarization, and it is easier to separate electrons and holes when their spin directions change. Electron paramagnetic resonance (EPR) results show that Vs-CuIn5S8-3 can produce more ROS. Under visible light irradiation, Vs-CuIn5S8-3 killed 99% of E. coli and MRSA in natural water within 30 minutes. The work adopted S-vacancies to regulate spin polarization and improve photocatalytic activity, which has great potential in natural water disinfection. [ABSTRACT FROM AUTHOR]

The smooth operation of the power system is of significant importance for ensuring societal stability. Therefore, regular inspections of the power system are necessary. The most efficient method for power inspection is to utilize Unmanned Aerial Vehicles (UAVs) to assist inspection. However, the UAV inspection still needs human resources to operate and manage the UAVs effectively. This paper proposes a UAV-airport power inspection system, where the airport can operate and manage UAVs instead of humans. The key contribution of the system is the computation offloading technology and the Wireless Power Transfer (WPT) capability. In other words, the airport can help UAVs execute electrical image fault detection and the UAVs can be charged by the airport. We propose a joint optimization strategy for UAV flight speed, local execution frequency for fault detection, and WPT time to maximize the number of images in the electrical dataset captured by the UAV that have undergone power fault detection within the inspection time. Comprehensive experiments are conducted to verify the performance of the UAV-airport power inspection system and our optimization strategy. [ABSTRACT FROM AUTHOR]

Objectives Design Methods Results Conclusions Impact Patient or Public Contribution To develop an instrument to facilitate the risk assessment of falls in older outpatients.A quantitative methodological study using the cross‐sectional data.This study enrolled 1988 older participants who underwent comprehensive geriatric assessment (CGA) in an outpatient clinic from May 2020 to November 2022. The history of any falls (≥1 falls in a year) and recurrent falls (≥2 falls in a year) were investigated. Potential risk factors of falls were selected by stepwise logistic regression, and a screening tool was constructed based on nomogram. The tool performance was compared with two reference tools (Fried Frailty Phenotype; CGA with 10 items, CGA‐10) by using receiver operating curves, sensitivity (Sen), specificity (Spe), and area under the curve (AUC).Age, unintentional weight loss, depression measured by the Patient Health Questionnaire‐2, muscle strength measured by the five times sit‐to‐stand test, and stand balance measured by semi‐ and full‐tandem standing were the most important risk factors for falls. A fall risk screening tool was constructed with the six measurements (FRST‐6). FRST‐6 showed the best AUC (Sen, Spe) of 0.75 (Sen = 0.72, Spe = 0.69) for recurrent falls and 0.65 (Sen = 0.74, Spe = 0.48) for any falls. FRST‐6 was comparable to CGA‐10 and outperformed FFP in performance.Age, depression, weight loss, gait, and balance were important risk factors of falls. The FRST‐6 tool based on these factors showed acceptable performance in risk stratification.Performing a multifactorial assessment in primary care clinics is urgent for falls prevention. The FRST‐6 provides a simple and practical way for falls risk screening. With this tool, healthcare professionals can efficiently identify patients at risk of falling and make appropriate recommendations in resource‐limited settings.No patient or public contribution was received, due to our study design. [ABSTRACT FROM AUTHOR]

To understand the plasma evolution mechanism of microwave ion source (MIS), a hybrid discharge heating (HDH) mode is proposed. That mode contains two parts: ignition discharge by surface wave plasma (SWP) and ionization by electron cyclotron resonance. Compared with the traditional electron cyclotron heating (ECH) mode, the HDH mode has a wider scope of application for MIS with a chamber diameter smaller than the cutoff size. The spatio-temporal evolution of electric field, power deposition, electron temperature, and electron density of a miniaturized microwave ion source (MMIS) at Peking University is investigated based on the HDH mode. In addition, the MMIS is optimized based on the theoretical results of the HDH mechanism. Preliminary experiments show that a mixed hydrogen continuous wave beam of up to 25 mA at 30 keV can be extracted with a power efficiency of 25 mA/100 W. [ABSTRACT FROM AUTHOR]

The mechanical properties of wheat grains were measured and analyzed using discrete element software, which provided crucial data for their processing in a mill. The foundational Hertz–Mindlin model was used as a theoretical framework to evaluate the accumulation angle of wheat grains. The Plackett–Burman, steepest ascent, and Box–Behnken methods were utilized in a series of experiments, with the accumulation angle serving as the dependent variable. Targeting the actual angle of repose in the response surface, the optimal parameters were derived using the regression equations. These included a static‐friction coefficient of 0.3 between individual wheat grains, rolling‐friction coefficient of 0.04 for wheat–wheat interactions, static‐friction coefficient of 0.554 for wheat–tooth roller interactions, collision recovery coefficient of 0.5 for wheat–wheat collisions, collision recovery coefficient of 0.45 for wheat–tooth roller collisions, and rolling‐friction coefficient of 0.05 for wheat–roller interactions. Relying on the bonding contact model of Hertz–Mindlin, virtual uniaxial compression tests were conducted to calibrate the wheat grain bonding parameters. A regression equation for the critical load was subsequently generated using the critical load of the wheat grain bonding model as the response variable. The optimal parameters were calculated and incorporated into the EDEM model for computation, which resulted in a relative error of 1.6% between the calculated and observed values, confirming the accuracy and feasibility of the calibration method, suggesting that the calibrated parameters were accurate. [ABSTRACT FROM AUTHOR]

Hydrogen production modules (HPMs) play a crucial role in harnessing abundant photovoltaic power by producing and supplying hydrogen to factories, resulting in significant operational cost reductions and efficient utilization of the photovoltaic panel output. However, the output of photovoltaic power is stochastic, which will affect the revenue of investing in an HPM. This paper presents a comprehensive analysis of HPMs, starting with the modeling of their operational process and investigating their influence on distribution system operations. Building upon these discussions, a deterministic optimization model is established to address the corresponding challenges. Furthermore, a two-stage stochastic planning model is proposed to determine optimal locations and sizes of HPMs in distribution systems, accounting for uncertainties. The objective of the two-stage stochastic planning model is to minimize the distribution system's operational costs plus the investment costs of the HPM subject to power flow constraints. To tackle the stochastic nature of photovoltaic power, a data-driven algorithm is introduced to cluster historical data into representative scenarios, effectively reducing the planning model's scale. To ensure an efficient solution, a Benders' decomposition-based algorithm is proposed, which is an iterative method with a fast convergence speed. The proposed model and algorithms are validated using a widely utilized IEEE 33-bus system through numerical experiments, demonstrating the optimality of the HPM plan generated by the algorithm. The proposed model and algorithms offer an effective approach for decision-makers in managing uncertainties and optimizing HPM deployment, paving the way for sustainable and efficient energy solutions in distribution systems. Sensitivity analysis verifies the optimality of the HPM's siting and sizing obtained by the proposed algorithm, which also reveals immense economic and environmental benefits. [ABSTRACT FROM AUTHOR]

Abiotic stresses can affect the outcome of plant–pathogen interactions, mostly by predisposing the host plant to infection; however, the crosstalk between pathogens and plants related to such predisposition remains unclear. Here, we investigated the predisposition of Carya cathayensis to infection by the fungal pathogen Botryosphaeria dothidea (Bd) caused by drought in the host plant. High levels of drought stress resulted in a significant increase in plant susceptibility to Bd. Drought significantly induced the accumulation of H2O2 and the free amino acids Pro, Leu, and Ile, and in the phloem tissues of plants, and decreased the content of non-structural carbohydrates. In vitro assays showed that Bd was sensitive to H2O2; however, Pro played a protective role against exogenous H2O2. Leu, Ile, and Pro induced asexual reproduction of Bd. Our results provide the first analysis of how drought predisposes C. cathayensis to Botrysphaeria canker via amino acid accumulation in the host plant, and we propose a model that integrates the plant–pathogen interactions involved. [ABSTRACT FROM AUTHOR]

Solid powder detonation technology was investigated in this study. Several problems related to the controllable and uniform injection of solid powder fuels were examined. This study demonstrated the feasibility of solid powder detonation technology by designing fluidization devices and evaluating the solid powder supply system. A stable supply of powder was achieved, and ignition tests were conducted using Al/H 2 /O 2 and H 2 /O 2 fuels. The maximum detonation wave velocity obtained using Al/H 2 /O 2 was 2950 m/s, which was 40% higher than that obtained using H 2 /O 2. We observed a mixed two-phase double-front detonation structure, with hydrogen/oxygen being detonated in the first front and aluminum powder/oxygen being detonated in the second wave. At a relatively low equivalence ratio, the aluminum powder/oxygen wave surface pressure was higher, whereas the hydrogen/oxygen wave surface pressure was higher at a higher equivalence. • This study proves the feasibility of solid powder detonation technology. • The stable supply of powder was successfully realized. • The maximum detonation wave velocity of solid powder was 2950 m/s. • A mixed two-phase double-front detonation structure was found. [ABSTRACT FROM AUTHOR]

Random Forest (RF) is a widely used machine learning method with good performance on classification and regression tasks. It works well under low sample size situations, which benefits applications in the field of biology. For example, gene expression data often involve much larger numbers of features (p) compared to the size of samples (n) . Though the predictive accuracy using RF is often high, there are some problems when selecting important genes using RF. The important genes selected by RF are usually scattered on the gene network, which conflicts with the biological assumption of functional consistency between effective features. To improve feature selection by incorporating external topological information between genes, we propose the Graph Random Forest (GRF) for identifying highly connected important features by involving the known biological network when constructing the forest. The algorithm can identify effective features that form highly connected sub-graphs and achieve equivalent classification accuracy to RF. To evaluate the capability of our proposed method, we conducted simulation experiments and applied the method to two real datasets—non-small cell lung cancer RNA-seq data from The Cancer Genome Atlas, and human embryonic stem cell RNA-seq dataset (GSE93593). The resulting high classification accuracy, connectivity of selected sub-graphs, and interpretable feature selection results suggest the method is a helpful addition to graph-based classification models and feature selection procedures. [ABSTRACT FROM AUTHOR]

The solid-fuel rotating detonation engine with gas generator is experimentally studied in this paper. This study solved the problems of ignition and stable detonation of pre-combustion gasification injection. The feasibility of solid pre-combustion rotating detonation is verified. A set of gas generators was designed and ignition tests were carried out. The detonation wave velocity is about 2625 m/s in the stable stage, which is about 20% higher than that generated by hydrogen/oxygen detonation. A maximum thrust of 69 N is obtained. Stable detonation pressure signal was obtained in our experiments. It is found that the detonation wave has experienced four stages in the formation process: deflagration, deflagration to detonation transition (DDT) process, galloping detonation, and stable detonation. In the stable detonation stage, coexistence of detonation waves with different strength is identified by high-speed photography images. • The feasibility of solid pre-combustion rotating detonation is verified. • The detonation wave velocity measured in the experiment is 2625 m/s. • The maximum thrust measured in the experiment is 69 N. • The detonation wave has experienced four stages in the formation process. [ABSTRACT FROM AUTHOR]

Electromagnetic navigation bronchoscopy (ENB) uses electromagnetic positioning technology to guide the bronchoscope to accurately and quickly reach the lesion along the planned path. However, enormous data in high-resolution lung computed tomography (CT) and the complex structure of multilevel branching bronchial tree make fast path search challenging for path planning. We propose a coordinate-based fast lightweight path search (CPS) algorithm for ENB. First, the centerline is extracted from the bronchial tree by applying topological thinning. Then, Euclidean-distance-based coordinate search is applied. The centerline points are represented by their coordinates, and adjacent points along the navigation path are selected considering the shortest Euclidean distance to the target on the centerline nearest the lesion. From the top of the trachea centerline, search is repeated until reaching the target. In 50 high-resolution lung CT images acquired from five scanners, the CPS algorithm achieves accuracy, average search time, and average memory consumption of 100%, 88.5 ms, and 166.0 MB, respectively, reducing search time by 74.3% and 73.1% and memory consumption by 83.3% and 83.0% compared with Dijkstra and A* algorithms, respectively. CPS algorithm is suitable for path search in multilevel branching bronchial tree navigation based on high-resolution lung CT images. [ABSTRACT FROM AUTHOR]

Traditional aqueous energy storage devices are difficult to operate at low temperatures owing to the poor ionic conductivity and sluggish interfacial dynamics in frozen electrolytes. Herein, the low‐cost brine refrigerants for food freezing and preservation as electrolytes, and unexpectedly realize high ionic conductivity and stable operation of an aqueous storage device at low temperatures are demonstrated. A CaCl2 brine refrigerant electrolyte (BRE) with a low freezing point −55 °C and high ionic conductivity (10.1 mS cm−1 at −50 °C) is developed for supercapacitors (SCs), which retains 80% of the room temperature capacity at −50 °C and exhibits ultra‐long cycle life with excellent capacity retention of 92% over 98,500 cycles, outperforming the other SCs which can be operated below −40 °C in literature. Moreover, the SCs with MgCl2 and NaCl BREs can also be operated successfully with excellent cycle stability and high‐capacity retention at low temperatures of −30 and −20 °C, respectively. Fundamental correlation between various cations and their effect on the freezing point reduction of aqueous electrolytes is revealed via Raman investigation and molecular dynamics simulations. This study provides a rational design strategy for green, inexpensive, and safe low‐temperature aqueous electrolytes for energy storage devices. [ABSTRACT FROM AUTHOR]

Over the last decades, growing crop production across China has had far-reaching consequences for both the environment and human welfare. One of the emerging questions is "how to meet the growing food demand in China?" In essence, the consensus is that the best way forward would be to increase crop yield rather than further extend the current cropland area. However, assessing progress in crop production is challenging as it is driven by multiple factors. To date, there are no studies to determine how multiple factors affect the crop production increase, considering both intensive farming (using yield and multiple cropping index) and large-scale farming (using mean parcel size and number of parcels). Using the Logarithmic-Mean-Divisia-Index (LMDI) decomposition method combined with statistical data and land cover data (GlobeLand30), we assess the contribution of intensive farming and large-scale farming changes to crop production dynamics at the national and county scale. Despite a negative contribution from MPS (mean parcel size, −25%), national crop production increased due to positive contributions from yield (+77%), MCI (multiple cropping index, +27%), as well as NP (number of parcels, +21%). This allowed China to meet the growing national crop demand. We further find that large differences across regions persist over time. For most counties, the increase in crop production is a consequence of improved yields. However, in the North China Plain, NP is another important factor leading to crop production improvement. On the other hand, regions witnessing a decrease in crop production (e.g., the southeast coastal area of China) were characterized by a remarkable decrease in yield and MCI. Our detailed analyses of crop production provide accurate estimates and therefore can guide policymakers in addressing food security issues. Specifically, besides stabilizing yield and maintaining the total NP, it would be advantageous for crop production to increase the mean parcel size and MCI through land consolidation and financial assistance for land transfer and advanced agricultural infrastructure. [ABSTRACT FROM AUTHOR]

Purpose: Automatic segmentation of colon, small intestine, and duodenum is a challenging task because of the great variability in the scale of the target organs. Multi‐scale features are the key to alleviating this problem. Previous works focused on extracting discriminative multi‐scale features through a hierarchical structure. Instead, the purpose of this work is to exploit these powerful multi‐scale features more efficiently. Methods: A Scale Attention Module (SAM) was proposed to recalibrate multi‐scale features by explicitly modeling their importance score adaptively. The SAM was introduced into the segmentation model to construct the Scale Attention Network (SANet). The multi‐scale features extracted from the encoder were first re‐extracted to obtain more specific multi‐scale features. Then the SAM was applied to recalibrate the features. Specifically, for the feature of each scale, a summation of Global Average Pooling and Global Max Pooling was used to create scale‐wise feature representations. According to the representations, a lightweight network was used to generate the importance score of each scale. The features were recalibrated based on the scores, and a simple pixel‐by‐pixel summation was used to fuse the multi‐scale features. The fused multi‐scale feature was fed into a segmentation head to complete the task. Results: The models were evaluated using fivefold cross‐validation on 70 upper abdominal computed tomography scans of patients in a volume manner. The results showed that SANet could effectively alleviate the scale‐variability problem and achieve better performance compared with UNet, Attention UNet, UNet++, Deeplabv3p, and CascadedUNet. The Dice similarity coefficients (DSCs) of colon, small intestine, and duodenum were (84.06 ± 3.66)%, (76.79 ± 5.12)%, and (61.68 ± 4.32)%, respectively. The HD95 were (7.51 ± 2.45) mm, (11.08 ± 2.45) mm, and (12.21 ± 1.95) mm, respectively. The values of relative volume difference were (3.4 ± 0.8)%, (11.6 ± 11.81)%, and (6.2 ± 3.71)%, respectively. The values of center‐of‐mass distance were 7.85 ± 2.82, 9.89 ± 2.70, and 9.94 ± 1.58, respectively. Compared with other attention modules and multi‐scale feature exploitation approaches, SAM could obtain a 0.83–2.71 points improvement in terms of DSC with a comparable or even less number of parameters. The extensive experiments confirmed the effectiveness of SAM. Conclusions: The SANet can efficiently exploit multi‐scale features to alleviate the scale‐variability problem and improve the segmentation performance on colon, small intestine, and duodenum of the upper abdomen. [ABSTRACT FROM AUTHOR]

The key scaffold of a pyrroloindole ring is a very important structure, which is isolated from plants and fungi with a variety of medical and fungicidal activities. In this paper, a series of pyrroloindole analogues were synthesized from indole-3-acetonitrile and screened for their antifungal activities against plant pathogenic fungi. Compounds a2 and a15 exhibited potent antifungal activities with a minimum inhibitory concentration of 15.63 μg mL−1 against 6 kinds of fungi, and can be used as novel antifungal agents for further development. [ABSTRACT FROM AUTHOR]

• The power performance of a small integrated PWR with proposed patterns was investigated. • BeO neutron reflector effectively increases radial power evenness and k eff at the end of life. • Proposing an alternative fuel reuse concept to build a multi-SMR power plant. This study used the community-developed Monte Carlo neutron transport code OpenMC to investigate the loading pattern of fuel assemblies in a small integrated pressurized water reactor (PWR) core. The System-Integrated Modular Advanced Reactor (SMART) core was selected as the reference. Initially, the core pattern employing the original two-batch refueling strategy and three proposed variants were considered. These variants occupy 57, 44, and 28 fresh fuel assemblies in different positions within the core. Subsequently, the optimizations of all introduced core patterns using beryllium oxide neutron reflectors were conducted. In these cases, the enrichment of fresh fuel is 4.8%, while the reloading fuel's enrichment was assumed to be 2.4%. The essential core parameters were calculated and verified, including the effective multiplication factor k eff , radial power spatial distribution, power-peaking factors, and effective full power days. Finally, based on the simulation outcomes, this work proposed a fuel-shifting strategy between different SMART unit cores and presented two hypothetical pathways for the staggered construction of an 1100MWe 10-SMART-unit nuclear power plant to optimize the demand for fresh fuel assembly. Through comparison and analysis of the obtained reactor core parameters, these findings offer valuable insights and references about fuel economic optimization for future core reloading and power plant operation. [ABSTRACT FROM AUTHOR]

• The proposed theoretical formula can effectively predict the critical wrinkling behavior of the inflated tube under pure bending. • The model considers the attenuation of the wrinkle amplitude in the circumferential direction. • Dimensionless geometric parameter h / R and internal pressure parameter p / E influence the critical wrinkling behavior. Inflatable tubes, owing to their lightweight and foldable characteristics, have important applications in soft robots and space expandable structures. The application of a bending load to the inflated tube might induce local instability on its compressed side, leading to the formation of wrinkles that could potentially compromise the structural strength. Therefore, it is necessary to have a comprehensive understanding of the wrinkling behavior exhibited by inflated tubes under bending load. Initially, a theoretical solution is developed for the critical wrinkling behavior of inflated tubes under pure bending, drawing upon the principle of minimum potential energy. According to the energy expression of the system, the critical wrinkling behavior of inflated tubes depends on dimensionless geometrical and internal pressure parameters. The critical wrinkling load and wrinkle pattern of the system are influenced by the thickness-radius ratio and the ratio of internal air pressure to Young's modulus. Subsequently, the theoretical solutions are validated through several finite element analysis examples and a systematic investigation is conducted into the influence of dimensionless geometrical and internal pressure parameters. Finally, the evolution of morphology in post-buckling is investigated through numerical results. The findings suggest that during post-buckling, the wrinkles may undergo a secondary bifurcation and evolve into a non-axisymmetric diamond-like pattern. These results hold significant implications for understanding the bending instability and failure mechanisms of inflated tubes. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Constructing sulfur vacancies on SnS 2 to induce spin polarization that avoids electron-hole recombination. • Superoxide radicals destroy bacterial cell membranes. • Sv-SnS 2 has broad-spectrum bactericidal properties under visible light. • Sv-SnS 2 has good biocompatibility. With the emergence and massive spread of antibiotic-resistant bacteria, it is urgent to develop new bactericidal technologies. Photocatalytic sterilization is a technique that uses solar energy to produce reactive oxygen species to kill pathogenic bacteria, and ROS effects depends on the charge separation characteristics of photocatalysts, so the development of strategies to promote charge separation is crucial. Here, we use the strategy of introducing sulfur vacancy on SnS 2 , effectively improving the separation of photogenerated charge. The femtosecond transient absorption results confirm that the charge lifetime of SnS 2 (Sv-SnS 2) after the introduction of the sulfur vacancy is 13.33 times that of pristine SnS 2. The DFT theoretical results confirm that sulfur vacancy causes spin polarization. It is easier to separate when the spin direction of the electrons and holes changes. In addition, the sulfur vacancy also expands the light absorption range and exposes the surface catalytic site. These phenomena lead to a higher ROS yield of Sv-SnS 2 (confirmed by electron paramagnetic resonance results). Thus, Sv-SnS 2 killed 99.99 % of E. coli and MRSA within 40 min under visible-light illumination. This efficient bactericidal performance can be attributed to improved photogenerated charge separation. This study confirms the effectiveness of sulfur vacancy strategy to improve charge separation and extend charge life, and applies it to the killing of antibiotic resistant bacteria, providing a new idea for the killing of resistant bacteria. [ABSTRACT FROM AUTHOR]

(a) The preparation process of composite materials (AmCs@ZIF-8); (b) The active sites and optimization process of Cu(II) and CR adsorption by composite materials (AmCs@ZIF-8) were analyzed by DFT theory; (c) Adsorption mechanism and properties of composites (AmCs@ZIF-8) compared with original materials. [Display omitted] • Developed novel hierarchical multi-site composite AmCs@ZIF-8. • The synergistic effect between AmCs and ZIF-8 enhanced the adsorbent performance. • The active sites and the mechanism of adsorption on the composite AmCs@ZIF-8 are unraveled by theoretical and experimental analysis. • Highly effective adsorption of Cu(II) and Congo Red (CR). In this study, we employed a straightforward in-situ synthesis strategy to fabricate multi-site adsorption functional composites known as aminated chitosan@ZIF-8 (AmCs@ZIF-8) for the efficient removal of Cu(II) and Congo red. The AmCs@ZIF-8 adsorbed Cu(II) at pH 5 and Congo red at pH 3 with excellent removal efficiency values of 94 % and 100 % respectively. The maximum adsorption capacity for Cu(II) and Congo red are obtained as 785 mg g−1 and 1156 mg g−1, respectively. Interestingly, AmCs@ZIF-8 composites exhibited an excellent removal efficiency (>80 %) after reusing them for four sequential cycles. Analysis of the adsorption isotherm and kinetic data indicated that chemisorption primarily governed the adsorption of Cu(II) and Congo red by AmCs@ZIF-8. Furthermore, we elucidated the adsorption energy of Cu(II) and Congo red on the AmCs@ZIF-8 composite through density functional theory. Specifically, the adsorption energy values for Cu(II) with AmCs and ZIF-8 were −20.907 and −57.809 kcal·mol−1, and −26.514 and −16.242 kcal·mol−1 for Congo red, respectively. The efficient adsorption mechanism of Cu(II) and Congo red on the AmCs@ZIF-8 composite can be attributed to the synergistic effects of chelation, electrostatic attraction, ion exchange, and hydrogen bonding through the analysis of experimental characterization and theoretical calculation. Therefore, AmCs@ZIF-8 composites elevate the adsorption capacity of Cu(II) and Congo red in a single-component system and exhibit high removal efficiency (>90 %) in the context of the Cu(II)-Congo red binary system. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to bring out the development of a flexible model for nonstationary crop yield distributions and its applications to decision-making in crop insurance. Design/methodology/approach: The authors design a nonparametric Bayesian approach based on Gaussian process regressions to model crop yields over time. Further flexibility is obtained via Bayesian model averaging that results in mixed Gaussian processes. Findings: Simulation results on crop insurance premium rates show that the proposed method compares favorably with conventional estimators, especially when the underlying distributions are nonstationary. Originality/value: Unlike conventional two-stage estimation, the proposed method models nonstationary crop yields in a single stage. The authors further adopt a decision theoretic framework in its empirical application and demonstrate that insurance companies can use the proposed method to effectively identify profitable policies under symmetric or asymmetric loss functions. [ABSTRACT FROM AUTHOR]

Background: To analyze the characteristics of basal thyroid hormone levels in infertile women consulting for assisted reproductive technology (ART) treatment.Methods: This was a retrospective study. Serum TSH, FT3 and FT4 levels of women seeking ART consultation were tested routinely. Analyses were performed based on age and sampling time. One-way ANOVA or Kruskal-Wallis rank sum test was used to compare the continuous data among the groups, and the chi-square test or Fisher's exact test was used to compare categorical data where appropriate.Results: A total of 6426 women were initially included in the study. After exclusion criteria were applied, the remaining 4126 women were categorized into different groups. The prevalence of subclinical hypothyroidism significantly decreased with age and sampling time, from 21.09 to 11.91% and from 28.57 to 10.67%, respectively (P < 0.001, respectively). Mean serum TSH, FT3, and FT4 levels decreased significantly with age (P = 0.017, < 0.001, < 0.001, respectively). In the context of sampling time, TSH levels from early in the morning were significantly higher (P < 0.001), while FT4 and FT3 levels were similar in different groups (P = 0.258, 0.300, respectively).Conclusions: The prevalence of subclinical hypothyroidism significantly decreased with increasing age and sampling time, as did the serum TSH levels. Even though, the establishment of reference interval of TSH level based on age or sampling time was not recommended. Full consideration of age and sampling time should be carefully taken before initiation of treatment. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the association between high-normal preconception TSH levels and reproductive outcomes in infertile women undergoing the first fresh D3 embryo transfer. Methods. This was a retrospective study. Euthyroid patients undergoing the first fresh D3 embryo transfer from January 2018 to May 2019 were initially included. The patients were divided into a low-TSH (0.27–2.5 mIU/L) group and a high-normal TSH (2.5–4.2 Miu) group. The reproductive outcomes were compared between the groups. Results. A total of 1786 women were ultimately included, in which 1008 of whom had serum TSH levels between 0.27 and 2.5 mIU/L and 778 of whom had serum TSH levels between 2.5 and 4.2 mIU/L. The patients were highly homogeneous in terms of general characteristics. High-normal TSH levels had no adverse impact on the clinical pregnancy rate, miscarriage rate, or live birth rate (respectively, aOR = 0.92, 1.30, and 0.88 and P = 0.416, 0.163, and 0.219). No significant differences were observed in terms of gestational age, single live birth rates, and birth weight, or birth length. Conclusion. High-normal TSH levels did not significantly influence reproductive outcomes in infertile women undergoing the first fresh D3 embryo transfer. Further studies are needed to test whether the results might be applicable to a wider population. [ABSTRACT FROM AUTHOR]

Global food trade has become an increasingly crucial element for feeding the world's population. Enhancing bilateral or multilateral trust in food safety in international food trade is not only important for promoting the sustainable development of trade but is also beneficial for cooperation when facing a global food crisis. However, highly credible traceability systems (TSs) for the cross‐border movement of food are still absent in many countries and regions. Blockchain is regarded as a promising technology that can help build trust for transparency and security issues. In this paper, an interconnected conceptual traceability framework based on blockchain is proposed in order to increase trust in food safety during food trade. Taking the food trade between China and the European Union as an example, a conceptual framework is designed in order to take full advantage of existing TSs in these two locations, and the features of logistical flow, data flow, and blockchain flow are analyzed. Considering the data capacity and data privacy level, a hybrid data storage method combining on‐chain and off‐chain is adopted. Smart contracts according to the features of cross‐border food trade—including the recording of exportation data, exporter inspection data, shipment data, importer inspection data, importation data, and tracing queries—are packaged and deployed to a blockchain network. An effective operation mechanism involving the distribution of related rights for different roles is presented. The blockchain‐based TS framework has the advantages of enhancing bilateral trust in cross‐border food trade, providing a flexible and intelligent technical framework, and having effective operability. Future challenges, such as data security, special smart contracts, and consensus mechanisms, and interoperability with other systems, are discussed. [ABSTRACT FROM AUTHOR]

Drought, which negatively affects crop yields, is expected to intensify in the future and will continue to threaten food security. Understanding crop yield responses to drought is essential for seeking more effective strategic adaptations and for reducing the risk of yield failure. However, how to regionally quantify drought-induced yield loss rates remains unclear. We addressed this gap through studying summer maize cultivated in the Huang-Huai-Hai farming region of China during 1981–2010. By incorporating yearly phenological data and dividing the growing season into the vegetative stage and reproductive stage, we used the standardized precipitation evapotranspiration index (SPEI) that is specific to different growth stages to reflect drought conditions. The spatial-temporal characteristics of drought conditions were further depicted, and the drought-induced yield loss rate was analyzed. The results showed that drought was unevenly and spatially distributed throughout the whole region, and extreme drought mostly occurred in the northern and northwestern regions even though they have a lower drought frequency. However, the drought tendency was alleviated across the maize growing season since the accumulated precipitation and average daily maximum temperature together determined the direction of drought severity. The drought-induced yield loss rate is related to both the intensification of extreme drought and the local precipitation conditions. These findings highlight the potential incentive of the drought-induced yield loss rate, and emphasize that innovation on farming activity is urgently needed to enhance maize productivity in regions with overexploited groundwater. [ABSTRACT FROM AUTHOR]

Background: Non-intubated thoracoscopic lung surgery has been reported to be technically feasible and safe. Spontaneous rupture of the esophagus, also known as Boerhaave's syndrome (BS), is rare after chest surgery.Case Presentation: A 60-year-old female non-smoker underwent non-intubated uniportal thoracoscopic wedge resection for a pulmonary nodule. Ultrasound-guided serratus anterior plane block was utilized for postoperative analgesia. However, the patient suffered from severe emesis, chest pain and dyspnea 6 h after the surgery. Emergency chest x-ray revealed right-sided hydropneumothorax. BS was diagnosed by chest tube drainage and computed tomography. Besides antibiotics and tube feeding, a naso-leakage drainage tube was inserted into the right thorax for pleural evacuation. Finally, the esophagus was healed 40d after the conservative treatment.Conclusions: Perioperative antiemetic therapy is an indispensable item of fast-track surgery. Moreover, BS should be kept in mind when the patients complain of chest distress following emesis after thoracic surgery. [ABSTRACT FROM AUTHOR]

Purpose. To investigate the association between high-normal preconception TSH levels and reproductive outcomes in infertile women undergoing the first single fresh D5 blastocyst transfer. Methods. This was a retrospective study. Euthyroid patients undergoing the first single fresh D5 blastocyst transfer from January 2018 to May 2019 were initially included. The patients were divided into a low TSH (0.27–2.5 mIU/L) group and a high-normal TSH (2.5–4.2 mIU/L) group. The reproductive outcomes were compared between the groups. Results. A total of 824 women were ultimately included, 460 of whom had serum TSH levels less than 2.5 mIU/L and 364 of whom had serum TSH levels between 2.5 and 4.2 mIU/L. The patients were highly homogeneous in terms of general characteristics. High-normal TSH levels had no adverse impact on the clinical pregnancy rate, miscarriage rate, or live birth rate (respectively, aOR = 0.84, 0.65, 0.61, and P = 0.234 , 0.145, 0.083). No significant differences were observed in terms of gestational age, single live birth rates, birth weight, or birth length. Conclusion. High-normal TSH levels did not significantly influence reproductive outcomes in infertile women undergoing the first single fresh D5 blastocyst transfer. Further studies are needed to test whether the results might be applicable to a wider population. [ABSTRACT FROM AUTHOR]

Information on global cropland distribution and agricultural production is critical for the world's agricultural monitoring and food security. We present datasets of cropland extent and agricultural production in a two-paper series of a cultivated planet in 2010. In the first part, we propose a new Self-adapting Statistics Allocation Model (SASAM) to develop the global map of cropland distribution. SASAM is based on the fusion of multiple existing cropland maps and multilevel statistics of the cropland area, which is independent of training samples. First, cropland area statistics are used to rank the input cropland maps, and then a scoring table is built to indicate the agreement among the input datasets. Secondly, statistics are allocated adaptively to the pixels with higher agreement scores until the cumulative cropland area is close to the statistics. The multilevel allocation results are then integrated to obtain the extent of cropland. We applied SASAM to produce a global cropland synergy map with a 500 m spatial resolution for circa 2010. The accuracy assessments show that the synergy map has higher accuracy than the input datasets and better consistency with the cropland statistics. The synergy cropland map is available via an open-data repository (10.7910/DVN/ZWSFAA; Lu et al., 2020). This new cropland map has been used as an essential input to the Spatial Production Allocation Model (SPAM) for producing the global dataset of agricultural production for circa 2010, which is described in the second part of the two-paper series. [ABSTRACT FROM AUTHOR]

La0.625Ca0.375MnO3 (LCMO) films with thicknesses between 7 and 54 nm were epitaxially grown on (LaAlO3)0.3(Sr2AlTaO6)0.35 (001) [LSAT (001)] substrates by using pulsed laser deposition. For this epitaxial system, antiferromagnetic-insulator (AFI) state can be controlled by changing the film thickness and annealing time with various epitaxial strain states, although this phenomenon is absent in the relatively thick films or bulk samples. The consistency between magnetization and resistivity data suggests all these interesting transport behaviors are attributed to the fluctuation of AFI volume fractions and their instability. Especially, there are huge low-field magnetoresistance over -54% (32 nm) at 0.1 T and enhanced magnetoresistance over a broad temperature range. Based on these above results, annealing induced coherent evolutions of biaxial strain and AFI phase in LCMO epitaxial films is a consequence of the strain-driven orbital ordered state, and this may make an approach for a possible application of strongly correlated electron devices. [ABSTRACT FROM AUTHOR]

Purpose: Serum anti-Mullerian hormone (AMH) shows a strong positive correlation to the number of oocytes retrieved but the patients undergoing assisted reproductive technology (ART) with lower AMH concentrations also could retrieve an ideal number of oocytes sometimes. The aim of the current study was to assess the performance of this population.Methods: This retrospective study included a total of 44 in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) treatment cycles as test group, in which their AMH levels were below the limit of reference range but more than 7 eggs were retrieved, and 103 control cases enrolled from May 2016 to December 2018 after matched with the same range of age from 24 to 38 years old and the same number range of retrieved oocytes from 7 to 18 and chosen randomly according to clinical ovarian stimulation protocols by the ratio of 3:7. Several parameters, which include age, basal endocrine status, number of oocytes, the maturation rate of eggs, 2PN fertilization rate, 3PN rate, total fertilization rate, cleavage rate, 8-cell embryo rate of D3 and the utilization rate of embryo, were compared and evaluated between two groups by Wilcoxon rank-sum test and t test for two independent samples.Results: Although the same age range from 24 to 38 years and the same retrieval eggs from 7 to 18, compared with the control group, the test group showed less number of oocytes collected (9.455 vs 10.767, p = 0.016), younger ages (28.36 vs 32.59, p = 0.000), and higher FSH of basal endocrine status (9.783 vs 7.338, p = 0.021). Between the two groups, there were no significant differences in parameters such as the mature eggs (7.05 vs 7.92, p = 0.079), the mature oocyte rate (74.189% vs 73.916%, p = 0.924), the number of 2PNs (5.36 vs 5.91, p = 0.236), 2PN rate (73.678% vs 75.125%, p = 0.769), the number of 3PNs (0.39 vs 0.50, p = 0.773), 3PN rate (5.104% vs 5.592%, p = 0.697), number of total fertilizations (6.77 vs 7.35, p = 0.241), total fertilization rate (96.461% vs 93.166%, p = 0.332), cleavage rate (82.003% vs 81.382%, p = 0.673), the number of 8-cells on D3 (1.59 vs 1.91, p = 0.227), the rate of 8-cell on D3 (36.259% vs 41.084%, p = 0.551) and the utilization rate of embryo (62.853% vs 61.824%, p = 0.806).Conclusions: These findings indicate that there are no significant differences in the maturation of oocytes and the embryo quality for the women with low AMH level and ideal retrieval eggs but they should undergo IVF treatment and achieve successful pregnancy as soon as possible due to the higher basal FSH, the relatively fewer number of retrieval eggs and the possibility of coming diminished ovarian reserve (DOR) or poor respond (PR) despite their younger ages. [ABSTRACT FROM AUTHOR]

In this paper, we establish a fluid-structure interaction (FSI) model to investigate the dynamic interactions between the underwater explosion (UNDEX) shock wave and a movable sphere near the free surface. We utilize the local discontinuous Galerkin (LDG) method to capture the propagation of the shock wave in the fluid domain and employ the pressure cutoff model to calculate cavitation effects. The fluid elements at the fluid-structure interface are directly coupled to the structural dynamic model, and the structural transient dynamic responses are coupled with fluid acoustic pressure at the fluid-structure interface in the governing equation. The validity of the present FSI model is verified by comparing with the continuous Galerkin method. Due to the advantage of the LDG method in capturing the discontinuous wave, the present model shows better properties than the traditional coupled acoustic-structural model. With the present FSI model, we investigate the interaction between the UNDEX shock wave and a submerged and floated sphere. Under the combined effects of the free surface and structure, the UNDEX shock and cavitation loading characteristics are analyzed, and the influences of complicated cavitation effects on dynamic responses of the sphere are discussed. [ABSTRACT FROM AUTHOR]

A quartz‐chamber 2.45‐GHz electron cyclotron resonance ion source (ECRIS) is designed at Peking University for the diagnostic purpose. Experimental results show that the added noble gases in hydrogen could cause a decrease of electron temperature and an increase of electron density. In this work, a numerical model is upgraded for ECR plasma generated by mixed gases. On this basis, the model is applied for the composed hydrogen plasma with additional noble gases. And dependences of neutral gas density and electron density on electron temperature are presented for individual gas (He, Ar, and H2) and gas mixture, respectively. The calculated results are basically in accordance with the diagnostic results of ECRIS. [ABSTRACT FROM AUTHOR]

Objective. To evaluate the impact of preconceptional serum TSH levels on the clinical outcomes of infertile patients undergoing their first IUI treatment cycle. Method. This was a retrospective study. Euthyroid patients undergoing the first cycle of IUI treatment from Jan 2017 to Aug 2018 were included. The patients were divided into a normal high TSH level (2.5–4.0 mIU/L) group and a low TSH level (0.4–2.5 mIU/L) group. Then, different factors were included separately to compare the outcomes between normal high and low TSH levels. The primary outcomes were clinical pregnancy rates, implantation rates, and miscarriage rates. The secondary outcomes were obstetric outcomes such as single live birth rates, birth length, birth weight, and duration of gestation. Results. Initially, 1856 patients were included, and 371 patients were excluded for different reasons. A total of 1485 patients were finally included in the analysis. The general parameters between normal high and low TSH levels were similar except for infertile duration and female BMI, which were, however, significantly different between AID-IUI patients and AIH-IUI patients (P = 0.005 and P = 0016). No significant differences were found in terms of either primary outcomes or secondary outcomes. Conclusion. Normal high-serum TSH levels within the reference range (0.4–4.0 mIU/L) measured before treatment seemed to have no adverse impact on the clinical outcomes of patients undergoing their first IUI treatment cycle. [ABSTRACT FROM AUTHOR]

At Peking University (PKU), experimental research as well as theoretical study on how to produce high intense H+, H2+, or H3+ dominated ion beams with a compact permanent magnet 2.45 GHz electron cyclotron resonance (PMECR) ion source have been continuously carried out in the past few decades. Based on the comprehension of hydrogen plasma processes inside a 2.45 GHz PMECR discharge chamber, a three-phase diagram of ion fraction dominant regions that illustrates the relationship between the H+, H2+, and H3+ ion species and working parameters was presented. Meanwhile, a numerical model based on the particle population balance equations was developed for quantitative comprehension of electron cyclotron heated hydrogen plasma. Calculated results of H+, H2+, and H3+ fractions against gas pressure, microwave density, and wall material obtained with this numerical model agree well with the measured ones. Recently, a miniaturized ECR ion source has been developed, and a 52 mA hydrogen beam was extracted. Under the guidance of the model, H+, H2+, and H3+ beams with a fraction of 88%, 80%, and 82%, respectively, were obtained with this miniaturized ECR ion source under suitable working parameters. A PMECR ion source for a proton therapy facility has been built at PKU recently. A 34 mA beam H+ fraction of 91% was obtained at the first attempt. [ABSTRACT FROM AUTHOR]

This paper aims to summarize the developments of high current H2+ and H3+ ion sources in the past decades. The status of the H2+ and H3+ ion sources is discussed to show the attempts researchers made to improve the beam currents of H2+ and H3+. The results of the 2.45 GHz electron cyclotron resonance ion source named PMECR II at Peking University are presented, which may provide an alternative reference for the design and operation of high current H2+ and H3+ ion sources. [ABSTRACT FROM AUTHOR]

Focuses on the fabrication of epitaxial La0.35Nd0.35Sr0.3Mn03 (LNSMO) thin films and Pb(Zr052Ti0.48)03 (PZT)/LNSMO heterostructures. Use of pulsed laser deposition method; Oxygen concentration in the LNSMO films; Electrical measurements of platinum/PZT/LNSMO ferroelectric capacitor.

Deals with a study on the effect of annealing in reduced oxygen pressure on the electrical transport properties of epitaxial thin films and bulk materials. Details on the experiment; Results and discussion; Conclusions.

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

Provides information on a study which examined the possible mechanism associated with the effect of annealing on the diamagnetic transition of bismuth, strontium, calcium, copper and oxygen crystals. Characterization by x-ray diffraction; Growth of crystals after annealing; Variations in crystallinity.

Presents a study which examined the intensity distribution of the modulation-related reflections in exactly the b*c* reciprocal plane for high quality bismuth[sub2]strontium[sub2]calcium copper[sub2]oxygen[suby] crystal. Experimental procedure; Results; Discussion.

Presents information on a study which described two different micromodels in zinc oxide (ZnO) varistors containing seed grains. Establishment of micromodel; Effect of the amount of seed grains on characteristics of ZnO varistors; Measurement of the electric field.

Presents information on a study which examined the phase decomposition in a high quality bismuth compound single crystal annealed in air, using x-ray diffraction and scanning electron microscopy. Methods; Results; Discussion.

La0.625Ca0.375MnO3 films have been epitaxially grown on the (LaAlO3)0.3(Sr2AlTaO6)0.35 (001) substrates at different oxygen pressures and show varying tetragonal distortion. Results indicate a tendency that larger tetragonal distortion can stabilize the antiferromagnetic-insulator phase in the thin films. Colossal magnetoresistance (CMR) and anisotropic magnetoresistance (AMR) have been greatly enhanced only in the strained films over a broad temperature, probably responding to the anisotropic fluctuation of the nanoscale orientation-ordered patterns near the temperature of the phase separation region or metal-insulator transition. Hence, the inhomogeneous phase competition may contribute to the CMR and the extraordinary AMR effect for manganite devices. [ABSTRACT FROM AUTHOR]

The scarcity of water resources is one of the biggest problems restricting food production. Crop water productivity (CWP) is a practical and quantifiable indicator for characterizing agricultural water use efficiency. Remote sensing technology provides an accurate, cost-effective, and regional method for estimating CWP. However, remote sensing methods for CWP estimation and their application scenarios need to be summarized. In this paper, the CWP and related parameters are clearly defined. Different types of CWP estimation methods and their application at different scales are reviewed. CWP, as the crop yield ratio to actual crop evapotranspiration (ETa), is typically not directly estimated but calculated by estimating crop yield and ETa. Therefore, crop yield and ETa estimation methods are summarized, respectively. ETa can be remotely sensed using surface energy balance residual methods, semi-empirical formula methods, statistical regression methods, and ground instruments. Crop yield can be remotely estimated using data assimilation, statistical regression, and ground instruments. Moreover, the application of these methods at the point, field, and regional scales is further reviewed from previous literature. Finally, the in-situ measurements of CWP are introduced. This review can provide a detailed reference for follow-up studies related to CWP. [ABSTRACT FROM AUTHOR]

Photodetector based on two‐dimensional (2D) materials is an ongoing quest in optoelectronics. 2D photodetectors are generally efficient at low illuminating power but suffer severe recombination processes at high power, which results in the sublinear power‐dependent photoresponse and lower optoelectronic efficiency. The desirable superlinear photocurrent is mostly achieved by sophisticated 2D heterostructures or device arrays, while 2D materials rarely show intrinsic superlinear photoresponse. This work reports the giant superlinear power dependence of photocurrent based on multilayer Ta2NiS5. While the fabricated photodetector exhibits good sensitivity (3.1 mS W−1per □) and fast photoresponse (31 µs), the bias‐, polarization‐, and spatial‐resolved measurements point to an intrinsic photoconductive mechanism. By increasing the incident power density from 1.5 to 200 µW µm−2, the photocurrent power dependence varies from sublinear to superlinear. At higher illuminating conditions, prominent superlinearity is observed with a giant power exponent of γ = 1.5. The unusual photoresponse can be explained by a two‐recombination‐center model where density of states of the recombination centers (RC) effectively closes all recombination channels. The photodetector is integrated into camera for taking photos with enhanced contrast due to superlinearity. This work provides an effective route to enable higher optoelectronic efficiency at extreme conditions. [ABSTRACT FROM AUTHOR]

Structural and microstructural characteristics, deformation temperatures and flow vorticities of the northern Ailao Shan (ALS) high-grade metamorphic belt provide significant information regarding the nature and tectonic evolution of the Ailao Shan-Red River (ASRR) shear zone. Mineral deformation mechanisms, quartz lattice-preferred orientation (LPO) patterns and the opening angles of quartz c-axis fabrics of samples from the Gasa section indicate that the northern ALS high-grade metamorphic belt has experienced progressive shear deformation. The early stage shearing is characterized by a gradual decrease of deformation temperatures from >650 °C at the northeastern unit to ca. 300 °C at the southwestern unit, that results in the formation of migmatites, mylonitic gneisses, thin bedded mylonites, mylonitic schists and phyllonites from the NE to SW across the strike of the shear zone. The late stage low-temperature (300–400 °C) shearing is superimposed on the early deformation throughout the belt with the formation of discrete, small-scale shear zones, especially in the thin-banded mylonitic rocks along both margins. The kinematic vorticity values estimated by rotated rigid porphyroclast method and oblique grain-shaped/quartz c-axis-fabric method imply that the general shear-dominated flow (0.49–0.77) progressively changed to a simple shear-dominated flow (0.77–1) toward the late stage of ductile deformation. The two stages of shearing are consistent with early shortening-dominated and late extrusion-controlled regional tectonic processes. The transition between them occurred at ca. 27 Ma in the ALS high-grade metamorphic belt along the ASRR shear zone. The large amount of strike-slip displacement along the ASRR shear zone is predominantly attributed to accelerated flow along the shear zone during the late extrusion-controlled tectonic process. [ABSTRACT FROM AUTHOR]

Total crop production is a function of the harvested area and the yield. Many studies have investigated opportunities to increase production by closing the yield gap and by expanding cropland area. However, the potential to increase the harvested area by increasing the cropping frequency on existing cropland has remained largely unexplored. Our study suggests that the attainable harvested area gap (HAG) in China ranges from 13.5 to 36.3 million ha, depending on the selected water allocation scenario, relative to the current harvested area of 160.0 million ha. Spatially, South China and the Lower Yangtze region have the largest potential to increase harvested area, as these regions allow triple-cropping, have sufficient water available, and have a good irrigation infrastructure. The results imply that management factors are equally important for exploring the potential against the resource endowment: water allocation has a large impact on both the size and the spatial pattern of the attainable HAG. This indicates the necessity of further examining the spatial-temporal dynamics of HAG at national and regional scales, and its potential contribution to food security and sustainable agricultural development. [ABSTRACT FROM AUTHOR]

The Ailaoshan tectonic belt, where the effects of the Paleo-Tethyan ocean evolution and Indian-Eurasian plate collision are superimposed, is one of the most significant geological discontinuities in western Yunnan province of southeast Tibet. An Ailaoshan micro-block within the belt is bounded by the Ailaoshan suture zone to the west and the Red River Fault to the east, and consists of low- and high-grade metamorphic belts. Late Permian-Middle Triassic granitoids that are widely distributed to the west of the Ailaoshan suture zone and within the Ailaoshan micro-block may yield significant information on the Tethyan tectonic evolution of the Ailaoshan tectonic belt. This study reports new LA-ICP-MS zircon U-Pb geochronology and Hf isotope data of four granitoids from the Ailaoshan high-grade metamorphic belt. Zircon grains from the Yinjie granitoid do not have inherited cores and yield a weighted mean U-Pb age of 247.1 ± 2.0 Ma. The zircon ε ( t) values range from 7.8 to 12.1, and Hf model ages from 775 to 546 Ma, indicating that the granitoid was derived from juvenile crust. The rims of zircons from the Majie and Yuanjiang granitoids yield weighted mean U-Pb ages of 239.5 ± 1.8 and 237.9 ± 2.6 Ma, respectively, whereas the cores yield ages of 1608-352 Ma. The ε ( t) values of zircon rims range from −20.4 to −5.3, yielding Hf model ages from 2557 to 1606 Ma and suggesting that the source magma of the Majie and Yuanjiang granitoids was derived from ancient crust. An additional granitoid located near the Majie Village yields a zircon U-Pb age of 241.2 ± 1.0 Ma. Based on our geochronological and geochemical data, combined with geological observations, we propose that the Ailaoshan micro-block was derived from the western margin of the Yangtze block, and is comparable to the Zhongzan and Nam Co micro-blocks. The presence of late Permian mafic rocks with rift-related geochemical characteristics within the Ailaoshan micro-block, together with granitoids derived from partial melting of ancient/juvenile crust, indicates the presence of an Ailaoshan rift. This possible rift may correspond to the Ganzi-Litang Ocean to the northwest and the Jinping-Song Da rift to the southeast. It is suggested that westward subduction of the Jinshajiang-Ailaoshan-Song Ma oceanic lithosphere triggered the separation of the Zhongzan, Ailaoshan, and Nam Co micro-blocks from the western passive continental margin of the Yangtze block through the opening of the Ganzi-Litang-Ailaoshan-Jinping-Song Da ocean/rift. This ocean/rift may represent a subsidiary branch of the Paleo-Tethyan Ocean along the western margin of the Yangtze block. [ABSTRACT FROM AUTHOR]

Accurate information of cropland area and spatial location is critical for studies of national food security, global environmental change, terrestrial ecosystem geophysics and the geochemical cycle. In this paper, we compared five global cropland datasets in circa 2010 of China from in terms of cropland area and spatial location, including GlobalLand30, FROM-GLC, GlobCover, MODIS Collection 5, and MODIS Cropland. The results showed that the accuracies of cropland area and spatial location of GlobeLand30 were higher than the other four products. The cropland areas of the five products varied in most of the provinces. Compared with the statistical data, the best goodness of fit was obtained using GlobeLand30, followed by MODIS Collection 5 and FROM-GLC, with MODIS Cropland and GlobCover having the poorer accuracies. Regarding the spatial location of cropland, GlobeLand30 achieved the best accuracy, followed by FROM-GLC and MODIS Collection 5, with GlobCover and MODIS Cropland having the poorer accuracies. In addition, the spatial agreement of the five datasets was reduced from agricultural production area to pastoral area and significantly affected by elevation and slope factors. Although the spatial resolution of MODIS Collection 5 was the lowest, accuracies of the cropland area and spatial location were better than those of GlobCover and MODIS Cropland. Therefore, high spatial resolution remote sensing images can help to improve the accuracy of the dataset during land cover mapping, while it is also important to select a suitable classification method. Furthermore, in northwestern and southeastern China, spectral mixing pixels are universal because of the complicated landscape and fragmentized topography and result in uncertainty and poor consistency when using the five products. Therefore, these regions require additional attention in future cropland mapping studies. [ABSTRACT FROM AUTHOR]

The pairwise separability index (SI) has been demonstrated as an effective indicator for capturing crucial phenological differences between two plant species. However, its application to crop types, which have more obvious phenological characteristics than natural vegetation, has received less attention, and extending the pairwise SI to multiple crops for feature selection still remains a challenge. This paper presented two SI extension approaches (\textSI\mathrm{ave} and \textSI\min) to select the optimal spectro-temporal features for multiple crops, and investigated their classification performance using Heilongjiang Province, China, as a study area. Feature interpretability and classification accuracy of different crops were evaluated for the two approaches. The results showed that the \textSI\mathrm{ave} approach generally has relatively high feature interpretability due to its better description of crucial phenological characteristics of different crops. Those crops with high separability are insensitive to the extension approach and have similar classification accuracy for the two approaches, whereas those crops with poor separability show good performance with the \textSI\min method. Due to the higher temporal autocorrelation, the optimal features for crop classification that are selected by the \textSI\mathrm{ave} approach exhibit greater information redundancy across the time domain than those that are selected by the \textSI\min approach, which largely explains the relatively low classification accuracy achieved using the \textSI\mathrm{ave} approach. These comparison results between \textSI\min and \textSI\mathrm{ave} approaches also indicate that time-series images with high temporal resolution do not necessarily produce high classification accuracy, regardless of their ability to describe the seasonal characteristics of crops. [ABSTRACT FROM PUBLISHER]

The underwater explosion (UNDEX) phenomenon involves hydrodynamic behaviors with a wide range of spatial scales, from macroscopic cavitation regions to refined areas with fluid-structure interactions around the shock wavefront. Correct description of the refined shock wavefront is important for determining the shock wave position and pressure peak. In this work, the local discontinuous Galerkin (LDG) method for the two-dimensional wave equation, which allows for the local triangular meshes refinement and merging during the shock wave propagation process, is presented to model the UNDEX shock hydrodynamics. This article is an extension of our previous work, where we discretize the UNDEX total wave formulation in the LDG framework and simulate the UNDEX shock wave and cavitation phenomenon. In order to save computational cost (including CPU time and computational storage) and capture the shock wavefront more accurately, the LDG method is extended to be in combination with the mesh adaption technique. The troubled-cell indicator, depending on the local jump of the pressure, is adopted to identify elements which require to be refined or coarsened. Typical numerical examples are tested to assess the capability of the present h -adaptive LDG method for capturing the UNDEX shock wave. The numerical results clearly demonstrate that the mesh adaption technique enables us to dynamically increase the mesh resolution in close proximity to the flow discontinuities with a large pressure jump. The local increase of the mesh resolution results in a substantial increase in the accuracy of the pressure peak. In terms of the computational efficiency, the h -adaptive LDG method can save nearly half of the calculation time in comparison to the non-adaptive LDG method on uniform meshes, whose mesh resolution is the same as that of the maximum level of refinement of the h -adaptive LDG method. • An h -adaptive LDG method is presented for simulating the UNDEX shock hydrodynamics. • The mesh resolution is adaptive with the evolution of the UNDEX shock wavefront. • The present h -adaptive LDG method can well capture the UNDEX pressure peak at a relative small computational cost. [ABSTRACT FROM AUTHOR]