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ABSTRACTEfficiently querying multiple spatial datasets is a challenging task in geoscience. The majority of spatial processing techniques use minimum bounding box (MBB) to approximate neighbouring spatial objects and and place them adjacent in the spatial index. However, due to the existence of redundant space in MBB of these methods, this problem can significantly reduce the query efficiency. In this paper, we propose a novel two-stage adaptive method of clipping the bounding box in spatial query, called IB-CBB (Intersection Based Clipped Bounding Boxes). The first stage employs a clipped bounding box, which records the redundant spatial spaces within the bounding box of the spatial index by calculating the clip points. As a result, the computational complexity of indexed child nodes in the query process is reduced. The second stage optimizes the above query algorithm by judging the intersection of the query box and the MBB of index node, significantly reducing the query time. Experiments demonstrate that IB-CBB outperforms the baseline method in terms of reducing the computational time.

Commercially pure titanium (CP–Ti) took advantages of low stiffness, high corrosion resistance and bio-compatibility, implying an ideal structural material in aerospace, military and medical industries. However, its insufficient mechanical properties have always been the long-standing obstacle for the industrial applications. In this work, we have achieved a superior strong and ductile CP-Ti via active atmosphere-assisted selective laser melting (SLM) and subsequent rolling treatment. By incorporating the active N2 atmosphere during SLM, mechanical properties of CP-Ti were substantially improved, microhardness of the lyaers with 10 at.% and 100 at.% was 63 % and 174.3 % higher than that of CP-Ti with 182.3 HV0.2, the compressive strength of 10 sample was 27.1 % higher than that of 10 L sample when the strain was 52.2 %, and ultimate tensile strength of 10 sample reached 928 MPa with an elongation of 25.6 %, and ultimate tensile strength and elongation of 10 L sample were enhanced simultaneously by 58.3 % and 13.6 % relative to CP-Ti sample. These were attributed to the interstitial strengthening induced by N atoms. After rolling treatment, the mechanical properties of N-doping layers could enhance furtherly. Macroscale cracking along the rolling direction never occur in the 10 L sample during the repeatedly rolling treatment, which could depend to high tolerability of sandwich layers for high-density dislocations. Meanwhile, rolling treatment played an important role for refining grain to enhance the strength further.

The hydrochemical characteristics of acid mine drainage (AMD) were investigated in Wuma River Basin, China. AMD was sampled from nine closed coal mine (CCM) sites to study the temporal and spatial evolution of pH, dissolved oxygen (DO), electrical conductivity (ED), total hardness (THR), total dissolved salt (TDS), and trace elements. The surface water (river) and groundwater surrounding mine sites were sampled to evaluate the potential pollution derived from AMDs. The TDS content of AMD was higher than that of surface water and groundwater. The dominant factors influencing TDS were the pH, temperature, and wet or dry season (which played a role in controlling microbial activity), HCO3− balance, and REDOX during the evolutionary process. The hydrochemical type of AMD was dependent on the evolutionary stage. From observations, most AMDs were in the form of the SO42--Ca2+•Mg2+ type that was characterized by a low pH, low [HCO3−], high [SO42−], and high [Fe]. In addition, the AMD samples were undergoing stage I and II processes, in which SO42− and trace elements were generated. The surface water and groundwater were primarily classified as the HCO3−-Ca2+•Mg2+ type, which accounted for their self-cleaning capacity, as indicated by the high [HCO3−]. The surface water and groundwater could be affected by the surrounding AMD depending on the geographical location. The surface water and groundwater sites that were located downstream of subsurface and surface runoff were obviously affected by AMD. After being polluted by AMD, surface water and groundwater contained higher levels of trace elements and emerged as the HCO3−•SO42--Ca2+•Mg2+ type.

Skeletal muscle has an essential role in boiler production, which depends on the muscle fibre development during the embryonic stage. Whereas the posttranslational modifications of both histone and non-histone proteins are known to regulate postnatal muscle development, the biological significance of non-histone methylation is poorly understood. Recently, the methyltransferase like 21 C (METTL21C) is identified as a non-histone lysine methyltransferase whose role in chicken muscle function remains elusive. In this study, METTL21C was found by comparing free-range and caged modes in Lueyang black-boned chicken aged 60 and 120 days. Quantitative real-time PCR (qPCR) analysis demonstrated that METTL21C was mainly enriched in chicken soleus (SOL) and gastrocnemius muscle (GA) (p

Oxidative stress increases the apoptosis of intestinal epithelial cells and impairs intestinal epithelial cell renewal, which further promotes intestinal barrier dysfunction and even death. Extensive evidence supports that resveratrol and apigenin have antioxidant, anti-inflammatory, and antiproliferative properties. Here, we investigated the ability of these two compounds to alleviate diquat-induced jejunal oxidative stress and morphological injury, using the duck as a model, as well as the effects of apigenin on oxidative stress induced by H2O2 in immortalized duck intestinal epithelial cells (IDECs). Ducks were randomly assigned to the following four groups, with five replicates: a control (CON) group, a diquat-challenged (DIQ) group, a resveratrol (500 mg/kg) + diquat (RES) group, and an apigenin (500 mg/kg) + diquat (API) group. We found that serum catalase (CAT) activity and total antioxidant capacity (T-AOC) markedly reduced in the RES and API groups as compared to the DIQ group (p < 0.05); moreover, serum S superoxide dismutase (SOD) levels increased significantly in the API group as compared to the DIQ group (p < 0.05). In jejunal mucosa, the malondialdehyde (MDA) content in the RES and API groups decreased more than that in the DIQ group (p < 0.05). In addition, the jejunal expression levels of the NRF2 and GCLM genes in the RES and API groups increased notably compared with those in the DIQ group (p < 0.05); meanwhile, CAT activity in the RES and API groups was markedly elevated compared with that in the CON group (p < 0.05). In IDECs, apigenin significantly restrained the H2O2-mediated increase in MDA content and decrease in CAT levels (p < 0.05). Furthermore, apigenin increased the protein expression of p-NRF2, NRF2, p-AKT, and p-P38; downregulated that of cleaved caspase-3 and cleaved caspase-9; and reduced the ratio of Bax/Bcl-2 in H2O2-treated IDECs (p < 0.05). In conclusion, resveratrol and apigenin can be used as natural feed additives to protect against jejunal oxidative stress in ducks.

The depletion and overuse of fossil fuels present formidable challenge to energy supply system and environment. The human society is in great need of clean, renewable and sustainable energy which can guarantee the long-term utilization without leading to escalation of greenhouse effect. Hydrogen, as an extraordinary secondary energy, is capable of realizing the target of environmental protection and transferring the intermittent primary energy to the application terminal, while its nature of low volumetric energy density and volatility need suitable storage method and proper carrier. In this context, liquid organic hydrogen carrier (LOHC), among a series of storage methods such as compressed and liquefied hydrogen, provokes a considerable amount of research interest, since it is proven to be a suitable carrier for hydrogen with safety and stability. However, the dehydrogenation of hydrogen-rich LOHC materials is an endothermic process and needs large energy consumption, which hampers the scale up of the LOHC system. The heat issue is thus essential to be addressed for fulfilling the potential of LOHC. In this work, several strategies of heat intensification and management for LOHC system, including the microwave irradiation, circulation of exhaust heat and direct LOHC fuel cell, are summarized and analyzed to provide suggestions and directions for future research.

BackgroundDepressive disorders have become an increasingly significant public health issue. This study is intended to show the trend of the incidence of depressive disorders in China, the United States, India and the world from 1990 to 2019, as well as the impact of age, period and cohort on it.MethodsExtracting incidence data from the Global Burden of Disease Study 2019, we determined trends in the age-standardized incidence rate (ASIR) using Joinpoint regression. An age-period-cohort analysis was implemented to describe the effects of age, period, and cohort, as well as the long-term tendencies.ResultsFrom 1990 to 2019, the ASIR of depressive disorders in China was lower than that in the United States; India is lower than the United States in the first 5 years, showing a downward trend. The incidence in India and the United States is higher than the global average. The ASIR of women in the three countries is higher than that of men. In China, the elderly, early period and people born around 1954 have a higher risk of depressive disorders. In the United States, young people born around 1999 have a higher risk of depressive disorders. India is similar to China.ConclusionFrom 1990 to 2019, the age effect of China as a whole increased, and the period became stable, and the cohort effect declined. The overall age and period effects of the United States reduced, while the cohort effect increased. The age effect in India increased, while the period and cohort effects decreased. Depressive disorders are becoming ever more serious worldwide, and we’d better take measures to reduce its incidence according to the cohort effect of each age group.

The challenge of how to effectively treat minerals in coal before synthetic graphitization is a practical problem. It is unrealistic to remove minerals completely via physical or chemical methods. So, it is essential to clarify the role of minerals in the synthetic graphitization of coal. Based on the complex mineral composition, the mixture samples consisting of coal and mineral are used to obtain the effect of minerals type and content on the synthetic graphitization of coal. The role of minerals in synthetic graphitization is closely associated with the mineral content and type, as well as the rank. As to the lower-rank anthracite, quartz, kaolinite, and calcite have the role of inhibitor for the yields and defect degrees of corresponding samples after synthetic graphitization derived from the mixtures, but the role of catalyzer for their crystal structure (the degree of graphitization, stacking height, lateral size). The increasing content of quartz, kaolinite, and calcite is harmful for the yield, but useful for the crystal structure and defect degrees; the increasing content of pyrite is harmful for the yield, degree of graphitization, and stacking height, and it is useful for defect degrees. As to the higher-rank anthracite, quartz, kaolinite, and calcite have the role of inhibitor for the yield of corresponding samples after synthetic graphitization, catalyzer for their crystal sizes (stacking height, lateral size), and inertia for their degrees of graphitization. The increasing content of quartz, kaolinite, calcite, and pyrite is harmful for the yield and crystal size. A lower coal rank indicates being more prone to positive mineral effects on synthetic graphitization. The role of minerals in the synthetic graphitization of coal is complex and also represents a coupling relationship with the thermal transformation of anthracite.

The effects of load and reciprocating frequency on reciprocating sliding of ZrO 2 /steel, Si 3 N 4 /steel, and SiC/steel under high water-based emulsion lubrication were studied by the ball-block sliding tester, including a series of tribological behavior and wear mechanisms. Through the analysis of the above characteristics, determine the influence of load and frequency on the friction and wear properties of the ceramic/steel friction pair. The results show that with the increase of load, the friction coefficient of the three ceramic friction pairs decreases, and the wear rate increases continuously. With the increase of frequency, the friction coefficients of ZrO 2 /steel and Si 3 N 4 /steel steadily decrease, the friction coefficient of SiC/steel increases slightly, and the wear rates of the three friction pairs decrease continuously. The comprehensive comparison shows that the ZrO 2 /steel friction pair shows the best tribological performance under different working conditions, which is more suitable for the friction pair material of high water-based hydraulic components, and the Si 3 N 4 /steel friction pair shows better wear resistance when the load is above 50 N.

Background: Peptic ulcer disease (PUD) is a common disease worldwide, especially in developing countries. China, Brazil, and India are among the world’s fastest-growing emerging economies. This study aimed to assess long-term trends in PUD mortality and explore the effects of age, period, and cohort in China, Brazil, and India. Methods: We collected data from the 2019 Global Burden of Disease Study and used an age–period–cohort (APC) model to estimate the effects of age, period, and cohort. We also obtained net drift, local drift, longitudinal age curve, and period/cohort rate ratios using the APC model. Results: Between 1990 and 2019, the age-standardized mortality rates (ASMRs) of PUD and PUD attributable to smoking showed a downward trend in all countries and both sexes. The local drift values for both sexes of all ages were below zero, and there were obvious sex differences in net drifts between China and India. India had a more pronounced upward trend in the age effects than other countries. The period and cohort effects had a similar declining trend in all countries and both sexes. Conclusions: China, Brazil, and India had an inspiring decrease in the ASMRs of PUD and PUD attributable to smoking and to period and cohort effects during 1990–2019. The decreasing rates of Helicobacter pylori infection and the implementation of tobacco-restricting policies may have contributed to this decrease.

BackgroundUpper limb spasticity (ULS) is a common complication after stroke, which seriously affects the quality of life and rehabilitation of patients. There are different treatment methods for post-stroke spasticity (PSS). Our group found that functional acupuncture (FA) can effectively improve forearm spasticity and hand dysfunction after stroke, but the efficacy of ULS needs to be further verified. Therefore, this subject has mainly used clinical randomized controlled trials to evaluate the clinical efficacy of FA in the treatment of ULS after ischemic stroke.MethodThis is a parallel design and randomized controlled trial. We selected 108 patients who met the predefined criteria and randomized them into two groups, the experimental group and the control group. The experimental group receives FA and routine rehabilitation treatment. The control group received traditional acupuncture (TA) and routine rehabilitation treatment. All patients received 20 courses of treatment for 4 weeks, and the modified Ashworth score (MAS), clinical neurological deficit score (CSS), Fugl-Meyer upper extremity function assessment (FMA-UE), and the Modified Barthel Index (MBI) scores were evaluated before and after treatment.DiscussionThis trial is mainly to study the clinical efficacy of FA in the treatment of ULS after ischemic stroke. It will not only provide a new idea for the clinical treatment of upper limb post-stroke spasticity (ULPSS) but also will provide effective experimental support and a theoretical basis for the clinic.Trial registrationChina Clinical Trials Registry No. ChiCTR2100050440. Registered on 27 August 27 2021.

Usage of high-energy ultrasonic vibration is an effective approach that can dramatically improve the performance of large-scale ingots. In this work, it was applied to manufacture large 2219 aluminum alloy ingots (630 mm in diameter and 4,500 mm in length). The degassing efficiency, the average size of α-Al grains, the morphology of the Al2Cu phase under double-source ultrasound (DSU), and three-source ultrasound (TSU) were compared. Meanwhile, the influence of the ultrasonic field on the macroscopic segregation of the Cu content and mechanical properties was scientifically investigated. It was found that the degassing efficiency of TSU was significantly higher than that of DSU. The results also indicated that α-Al grains were effectively refined under the TSU technology from the center to the edge of the ingot. Additionally, the distribution of the macroscopic Cu content was more uniform, and the area fraction of the Al2Cu phase was evidently decreased. The mechanical properties of the ingot were superior to samples with DSU technology. Furthermore, it was demonstrated that the stress concentration of the coarse Al2Cu phase at the center of the DSU process led to the deterioration of the mechanical properties.

Under low speed and heavy load operating conditions, the marine water-lubricated bearing (WLB) is often in a mixed lubrication state. This leads to abnormal friction-induced vibrations and noise in underwater vehicles. An empirical mode decomposition (EMD) based method for identifying friction-induced vibration characteristics of WLB was proposed, and friction-induced vibration experiments of WLB were carried out. The results showed that the specific pressure and lubricant temperature significantly affected friction-induced vibrations while the cooling water flow hardly had an effect. Studying the monotonicity of the eigenvalues of IMF energy, time-domain standard deviation, bias angle, and center of gravity frequency can visualize the trend of the bearing friction-induced vibration signals. Among them, the critical point of friction-induced vibrations could be analyzed by the inflection point of IMF energy, standard deviation, bias angle, and the sudden increase of the center of gravity frequency. The study results were valuable for revealing the friction-induced vibration mechanism of WLB and providing an important reference for design optimization.

BackgroundPost-stroke depression (PSD), a common neuropsychiatric comorbidity after stroke, has a negative impact on the functional recovery and quality of life of survivors. It lacks effective therapeutic drugs with good curative effects and few adverse reactions. Preliminary experiments have shown that the optimized acupuncture and moxibustion treatment (OAMT), including acupuncture, moxibustion, and auricular intradermal acupuncture, improved depressive symptoms and neurological deficits in patients with PSD. However, the evidence for its effectiveness is still insufficient. Hence, we designed this study to evaluate the efficacy and safety of the OAMT in the treatment of PSD and to explore its possible mechanism from the perspective of executive functions.Methods/DesignThis is a randomized controlled trial, which comprises a total of 134 patients with PSD. Participants are randomized into intervention group and control group at a 1:1 ratio. All treatments are given five times per week for 4 weeks. The primary outcome is the severity of depression, which is evaluated by the Hamilton Depression Scale-17 (HAMD-17) and the Beck Depression Rating Scale (BDI). Secondary outcomes are executive abilities, which are measured by several neuropsychological tests, including the Stroop Color and Word Test (SCWT), the Trial Making Test (TMT), the Digit Symbol Substitution Test (DSST), and the Matrix Reasoning Test (MRT). All outcomes have been evaluated at baseline and weeks 4, 8, 12, and 20. At the same time, functional MRI (fMRI) is used to measure the functional connectivity in the cognitive control network (CCN) at baseline and 4 weeks after intervention.DiscussionThis study aims to provide high-quality evidence for the efficacy and safety of the OAMT for treating PSD. In addition, this trial is the first trial to explore if the improvement condition of depression in the OAMT group is related to the improvement of executive functions and the favorable changes in the structure.Clinical Trial RegistrationChinese Clinical Trial Registry, identifier: ChiCTR2100048431.

High-entropy alloys (HEAs) have excellent properties of high strength–ductility, thermal stability, corrosion resistance, etc. HEAs can be considered as one of the most interesting structural or functional candidate materials and have been extensively studied based on different multiple elements in the past decades. However, the previous works focus mainly on overcoming strength–ductility trade-off. In this study, a series of WCp-reinforced FeCrMnCox (x values in atomic ratio, x = 0, 2, 4, 6, 8, and 10 at.%) HEAs are fabricated to investigate the influence of Co on the microstructures, microhardness, cracking behavior, and wear resistance. The results indicate that γ phase (fcc structure) can be formed in the designed HEA with a small amount of α phase (bcc structure). Stress can result in cracking initiation owing to the formation of lattice distortion caused by the decomposition and diffusion of WC into the matrix, and the cracking phenomenon is more serious when Co content is decreased gradually. In addition, microhardness is also increased gradually with the decrease in Co content, and the maximum microhardness reaches 680 HV for the 0–2 sample without Co. Furthermore, excellent wear resistance of the designed materials can be attributed mainly to hardness rather than friction coefficient. A conspicuous monotonic decrease in the wear rate is discovered with a monotonic increase in microhardness, adhesive wear mechanism appears mainly in the samples with higher Co content, and the wear mechanism is transformed gradually from a typical adhesive wear mechanism to an abrasive wear mechanism with the reduction in Co content.

BackgroundExercise is increasingly recognized as a key component of Parkinson’s disease (PD) treatment strategies, but the underlying mechanism of how exercise affects PD is not yet fully understood.ObjectiveThe activation likelihood estimation (ALE) method is used to study the mechanism of exercise affecting PD, providing a theoretical basis for studying exercise and PD, and promoting the health of patients with PD.MethodsRelevant keywords were searched on the PubMed, Cochrane Library, and Web of Science databases. Seven articles were finally included according to the screening criteria, with a total sample size of 97 individuals. Using the GingerALE 3.0.2 software, an ALE meta-analysis was performed using seven studies that met the requirements, and the probability of the cross-experiment activation of each voxel was calculated.ResultsThe meta-analysis produced seven clusters, and major activations were found in the cerebellum, occipital lobe, parietal lobe, and frontal lobe brain regions.ConclusionExercise for PD mainly results in the enhanced activation of the cerebellum, occipital lobe, parietal lobe, and frontal lobe. Exercise for PD does not cause a change in the activation of a single brain area, and the observed improvement may result from coordinated changes in multiple brain areas.

The objective of the present study was to evaluate the effects of hydroxylated lecithin on growth performance, serum enzyme activity, hormone levels related to lipid metabolism and meat quality in Jiangnan White goslings. Six hundred 1-day-old goslings were randomly divided into five treatments with six replicates and 20 for each replicate. The control group (CG) was fed the basal diet, while the experimental group was fed the basal diet with 50, 100, 200 mg/kg hydroxylated lecithin and 100 mg/kg soy lecithin (HLG50, HLG100, HLG200, and LG100, respectively) in the form of powder. Feed and water were provided ad libitum for 32 days. Compared with the CG, (a) the average daily feed intake was higher (P < 0.05) in HLG100, the final body weight and average daily gain were higher (P < 0.05), and the feed conversion ratio was lower in the HLG200; (b) the alanine aminotransferase, malate dehydrogenase, leptin, glucagon, thyroid hormone, Triiodothyronine contents in the HLG200 were lower (P < 0.05); (c) The breast muscle water holding capacity was higher (P < 0.05) in groups with hydroxylated lecithin, the breast muscle shear force and fiber diameter were lower (P < 0.05) in the HLG100; (d) the inositic acid, intramuscular fat, phospholipid contents were higher (P < 0.05), the triglyceride content was lower (P < 0.05) in HLG100 of the breast muscle; (e) the relative expression of sterol regulatory element-binding protein-1 genes were higher (P < 0.05) in the treated groups of muscles, the phosphorylase kinase gamma subunit 1 gene expression was shown an opposite trend. In comparison with LG100, (a) the feed conversion ratio was lower (P < 0.05) in HLG200; (b) the alanine aminotransferase and adiponectin contents were higher (P < 0.05), the malondialdehyde and free fatty acid contents were lower (P < 0.05) in HLG200; (c) the water holding capacity and intramuscular fat contents in the breast and leg muscles were higher (P < 0.05) in HLG200. The hydroxylated lecithin concentration of 200 mg/kg improved the growth performance, serum enzyme activity, hormone levels related to lipid metabolism, and the meat quality of Jiangnan White goslings.

Kinesin family member 2C (KIF2C) is known as an oncogenic gene to regulate tumor progression and metastasis. However, its pan-cancer analysis has not been reported. In this study, we comprehensively analyzed the characteristics of KIF2C in various cancers. We found that KIF2C was highly expressed and corresponded to a poor prognosis in various cancers. We also found a significant correlation between KIF2C and clinicopathological characteristics, particularly in cervical cancer, which is the most common gynecological malignancy and is the second leading cause of cancer-related deaths among women worldwide. KIF2C mutation is strongly associated with the survival rate of cervical cancer, and KIF2C expression was significantly upregulated in cervical cancer tissues and cervical cancer cells. Moreover, KIF2C promoted cervical cancer cells proliferation, invasion, and migration in vitro and as well increased tumor growth in vivo. KIF2C knockdown promotes the activation of the p53 signaling pathway by regulating the expression of related proteins. The rescue assay with KIF2C and p53 double knockdown partially reversed the inhibitory influence of KIF2C silencing on cervical cancer processes. In summary, our study provided a relatively comprehensive description of KIF2C as an oncogenic gene and suggested KIF2C as a therapeutic target for cervical cancer.

The radial fluid flow in fractures is affected by the size of the inner diameter and the position of the outer diameter, but the influence of the two factors on the flow velocity remains unclear. This study reveals the relationship through the coupled shear flow experiments and numerical simulations. Experimental results show that the fracture aperture is decreased by 0.175 mm under the unit effective stress, with the increase of 0.902 MPa in the shear stress. COMSOL is used to simulate the seepage of fractures under different inner and outer diameters. Simulation results show that the transition from nonlinear to linear flow occurs in the radial direction when the hydraulic pressure is 0.2 and 0.4 MPa, and the positions of linear flow are 42 mm and 71 mm. The effect of the fracture surface results in a stratified flow velocity when the fluid flow enters the fracture aperture. Increasing the inner diameter raises the flow rate but decreases the maximum flow velocity. The maximum velocity difference can be as much as three times when the inner diameter difference is 6 mm. The seepage width of radial flow has a nonlinear relationship with the inner and outer diameters. The growth rate of the seepage width decreases as the ratio of the outer to the inner diameter increases. The modified cubic law considering the radius effect is proposed to improve the calculation accuracy of radial flow.

Abstract Clean utilization of coal depends on the quality of raw coal, which depends on the coal-forming parent materials (petrology and chemical composition of coal), the multiple media of the coal-forming environment, and some epigenetic conditions, such as thermal evolution (coalification), magmatic hydrothermal fluid, groundwater. Based on the research results of predecessors and prediction studies of coal resources since the founding of China, the present status of research on coal petrology, coal quality, coal metamorphism, and coal geochemistry in China is discussed in detail, with emphasis on research progress and the general situation of highly efficient and clean utilization of coal in the technical fields of coking, pyrolysis, combustion, gasification, and liquefaction, and the development prospects of coal petrology and coal quality in China are prospected.

Starch provides primary storage of carbohydrates, accounting for approximately 85% of the dry weight of cereal endosperm. Cereal seeds contribute to maximum annual starch production and provide the primary food for humans and livestock worldwide. However, the growing demand for starch in food and industry and the increasing loss of arable land with urbanization emphasizes the urgency to understand starch biosynthesis and its regulation. Here, we first summarized the regulatory signaling pathways about leaf starch biosynthesis. Subsequently, we paid more attention to how transcriptional factors (TFs) systematically respond to various stimulants via the regulation of the enzymes during starch biosynthesis. Finally, some strategies to improve cereal yield and quality were put forward based on the previous reports. This review would collectively help to design future studies on starch biosynthesis in cereal crops.

In this work, we fabricated VCp-reinforced iron-based composites (VCFCs) by adjusting the amount of Mn elements and investigated how the concentration of Mn affected the microstructural characteristics of Vanadium carbide (VC) and the texture of the iron matrix, and the influence of microstructure on tribological behaviors should be investigated. We demonstrated that VC changed from thick dendrite crystals (~50 μm) to tiny equiaxed crystals (~5 μm). Furthermore, the nucleation mechanism of VC also transformed from homogeneous nucleation to heterogeneous nucleation due to the lower Gibbs free energy of TiC and the tailoring effect of the Mn elements. In addition, γ-Fe in the FCC structure gradually increased and ascribed an increase of Mn content to the lower transformation temperature of martensite. Furtherly, particulate features and phase constitution could contribute to hardness and wear resistance. Higher hardness and excellent wear resistance occurred in the 3.0 Mn sample, which had a hardness of 869 HV and a wear rate of 1.77 × 10−6 mm3/(N·m). In addition, the adhesive wear could be the main wear mechanism in the 3.0 Mn sample, while the abrasive wear could be in the 4.5 Mn sample.

With increasing areas of direct sowing, low-temperature (LT) stress drastically affects global rice production. Exogenous applications of melatonin (MT) serve as one of the effective ways to improve seed germination under various stress conditions. In this study, we found that MT treatment greatly improved the LT stress-induced loss of germination percentage and the weak performance of seedlings under LT of constant 20°C (LT20). This was largely dependent on the activated antioxidant system and enhanced activities of storage substance utilization-associated enzymes. Moreover, we also detected that exogenous feeding of MT significantly increased the biosynthesis of gibberellin (GA) and endogenous MT but simultaneously inhibited the accumulation of abscisic acid (ABA) and hydrogen peroxide (H2O2) under LT20 stress. These results suggested that MT had antagonistic effects on ABA and H2O2. In addition, MT treatment also significantly enhanced the expression of CATALYSE 2 (OsCAT2), which was directly regulated by ABA-INSENSITIVE 5 (OsABI5), a core module of ABA-stressed signals, and thus promoting the H2O2 scavenging to reach reactive oxygen species (ROS) homeostasis, which consequently increased GA biosynthesis. However, in abi5 mutants, OsCAT2 failed in response to LT20 stress irrespective of MT treatment, indicating that OsABI5 is essential for MT-mediated seed germination under LT20 stress. Collectively, we now demonstrated that MT showed a synergistic interaction with an ABI5-mediated signal to mediate seed germination, partially through the direct regulation of OsCAT2.

Online visualization and query of massive geo-spatial data are facing increasing challenges with the explosive growth of location-based spatial datasets. In the practical scenario, online visualization is carried out in a progressive way, namely, a sketchy view map is first presented, and more detailed view maps are produced gradually as the viewport scale goes deeper. One approach is to use the multi-scale spatial index technique. However, it loses the original data attribute and cannot provide spatial statistics information. The paper is to provide an improved index structure, the Geo-Gap tree, which aims to enhance online interactive access to large spatial datasets, as well as enable one to compute statistical attributes like aggregation at the coarse level. Therefore, the first focus of Geo-Gap tree is improving the efficiency of tree building. For this purpose, an adaptive geohash coding is introduced to reduce the computing of neighboring objects. And, this phase can be improved in parallel once objects are partitioned. Compare to Gap tree, the cost of building the Geo-Gap tree can be greatly reduced. The second contribution is to choose data at different level based on sampling so that a sample for each level can be served as a progressive query result. The third contribution is an estimation of progressive query results, which ensure that progressive query accuracy can be controlled within the range of theoretical analysis. With the query continuing to execute, the query results become more and more accurate. The method is now integrated successfully into a high-performance geographic information system called HiGIS.

Thirteen raw coal samples from Qinshui coalfield were prepared to produce coal-based graphene, and the raw coal, coal-based graphite, and coal-based graphene sheets (GS) were characterized by X-ray diffraction (XRD), Raman spectroscopy, scanning electron microscopy with energy dispersive spectrometer (SEM-EDS), and high-resolution transmission electron microscopy (HRTEM). The results show that the graphitization degree of coal-based graphite is positively linearly correlated with the reflectance of raw coal, has a low positive correlation with the content of inertinite, and has a low positive correlation with the content of vitrinite in raw coal. The crystallite width (La) and crystallite height (Lc) of coal-based graphite and graphene are positively linearly correlated with the reflectance of raw coal. La and Lc of coal-based graphite are distributed in 17.591–48.374 nm and 11.359–23.023 nm, respectively. After redox, La and Lc of coal-based graphene are distributed in 4.405 nm–6.243 nm and 0.804–1.144 nm, respectively. The defect degree (ID/IG) of coal-based graphene is higher than that of raw coal, demineralized coal, and coal-based graphite. The coal-based graphene is thin and transparent, and only contained carbon and oxygen. Combined with the parameters of XRD and HRTEM, it is calculated that the interlayer spacing (d002) of Qinshui-coal-based graphene is about 0.4007 nm and the number of layers (Nave) is about 5.

Resveratrol is a polyphenolic compound with anti-oxidation effects. The mechanisms underlying the antioxidant effects of resveratrol in duck intestinal epithelial cells remain unclear. The protective effects of resveratrol against oxidative stress induced by H2O2 on immortalized duck intestinal epithelial cells (IDECs) were investigated. IDECs were established by transferring the lentivirus-mediated simian virus 40 large T (SV40T) gene into small intestinal epithelial cells derived from duck embryos. IDECs were morphologically indistinguishable from the primary intestinal epithelial cells. The marker protein cytokeratin 18 (CK18) was also detected in the cultured cells. We found that resveratrol significantly increased the cell viability and activity of catalase and decreased the level of intracellular reactive oxygen species and malondialdehyde, as well as the apoptosis rate induced by H2O2 (p < 0.05). Resveratrol up-regulated the expression of NRF2, p-NRF2, p-AKT, and p-P38 proteins and decreased the levels of cleaved caspase-3 and cleaved caspase-9 and the ratio of Bax to Bcl-2 in H2O2-induced IDECs (p < 0.05). Our findings revealed that resveratrol might alleviate oxidative stress by the PI3K/AKT and P38 MAPK signal pathways and inhibit apoptosis by altering the levels of cleaved caspase-3, cleaved caspase-9, Bax, and Bcl-2 in IDECs exposed to H2O2.

Drought has become one of the environmental threats to agriculture and food security. Applications of melatonin (MT) serve as an effective way to alleviate drought stress, but the underlying mechanism remains poorly understood. Here, we found that foliar spray of 100-µM MT greatly mitigated the severe drought stress-induced damages in rice seedlings, including improved survival rates, enhanced antioxidant system, and adjusted osmotic balance. However, mutation of the suppressor of the G2 allele of skp1 (OsSGT1) and ABSCISIC ACID INSENSITIVE 5 (OsABI5) abolished the effects of MT. Furthermore, the upregulated expression of OsABI5 was detected in wild type (WT) under drought stress, irrespective of MT treatment, whereas OsABI5 was significantly downregulated in sgt1 and sgt1abi5 mutants. In contrast, no change of the OsSGT1 expression level was detected in abi5. Moreover, mutation of OsSGT1 and OsABI5 significantly suppressed the expression of genes associated with the antioxidant system. These results suggested that the functions of OsSGT1 in the MT-mediated alleviation of drought stress were associated with the ABI5-mediated signals. Collectively, we demonstrated that OsSGT1 was involved in the drought response of rice and that melatonin promoted SGT1-involved signals to ameliorate drought stress adaption.

An Al-Cu alloy ingot was produced with the application of ultrasonic melt treatment. The effects of ultrasonication on the grain structure, eutectic phase, solution, and tensile properties of the alloy were analyzed. The volume and distribution of the eutectic phase were quantitatively evaluated based on stereological theory. The results are as follows: The grain-refinement efficiency at the center, 1/2 radius and edge of the ingot is 33.99%, 45.2% and 41.68%, respectively, under the action of an ultrasonic field. Ultrasonics improves the solid solubility of the Al-Cu alloy element, in which the solid solubility of Cu increases from 0.85% to 1.42%. The ultrasonic field improves the dispersion degree of the eutectic phase and reduces the volume fraction and eutectic phase number per unit volume. The mechanical properties of the Al-Cu alloy were improved by an ultrasonic field.

Starch is the main food source for human beings and livestock all over the world, and it is also the raw material for production of industrial alcohol and biofuel. A considerable part of the world’s annual starch production comes from crops and their seeds. With the increasing demand for starch from food and non-food industries and the growing loss of arable land due to urbanization, understanding starch biosynthesis and its regulators is essential to produce the desirable traits as well as more and better polymers via biotechnological approaches in cereal crops. Because of the complexity and flexibility of carbon allocation in the formation of endosperm starch, cereal crops require a broad range of enzymes and one matching network of regulators to control the providential functioning of these starch biosynthetic enzymes. Here, we comprehensively summarize the current knowledge about regulatory factors of starch biosynthesis in cereal crops, with an emphasis on the transcription factors that directly regulate starch biosynthesis. This review will provide new insights for the manipulation of bioengineering and starch biosynthesis to improve starch yields or qualities in our diets and in industry.

For a long time, temperature control and crack prevention of mass concrete is a difficult job in engineering. For temperature control and crack prevention, the most effective and common-used method is to embed cooling pipe in mass concrete. At present, there still exists some challenges in the precise simulation of pipe cooling in mass concrete, which is a complex heat-flow coupling problem. Numerical simulation is faced with the problem of over-simplification and inaccuracy. In this study, precise simulation of heat-flow coupling of pipe cooling in mass concrete is carried out based on finite element software COMSOL Multiphysics 5.4. Simulation results are comprehensively verified with results from theoretical solutions and equivalent algorithms, which prove the correctness and feasibility of precise simulation. Compared with an equivalent algorithm, precise simulation of pipe cooling in mass concrete can characterize the sharp temperature gradient around cooling pipe and the temperature rise of cooling water along pipeline more realistically. In addition, the cooling effects and local temperature gradient under different water flow (0.60 m3/h, 1.20 m3/h, and 1.80 m3/h) and water temperature (5 °C, 10 °C, and 15 °C) are comprehensively studied and related engineering suggestions are given.

In this study, four kinds of heat treatments were performed to obtain a certain amount of retained austenite, which can result in good toughness and low brittleness accompanied with wear resistance of an in situ VC particle reinforced iron-based composite (VCFC). Microstructure, mechanical properties and wear resistance of the samples under heat treatment of QP, QPT, MQP and MQPT were compared. The experimental results indicated that there is a huge difference in microstructure between MQPT and the other heat treatments. High-proportion retained austenite and white net-like precipitates of M7C3 carbide existed in the MQPT-treated sample, but thick M7C3 carbide with brittleness was discovered in the other sample. Thereby, high-proportion retained austenite contributed to its low hardness of 634 HV and high tensile strength of 267 MPa, while a maximum hardness of 705.5 HV and a minimum tensile strength of 205 MPa were exhibited in the QPT-treated sample with a V-rich carbide of high hardness, a Cr-rich carbide of brittleness and a high-proportion martensite. Meanwhile, a phase transformation from retained austenite to martensite could increase the hardness and enhance wear resistance based on the transformation-induced plasticity (TRIP) effect; its wear rate was only 1.83 × 10−6 mm−3/(N·m). However, the wear rates of the samples under QP, QPT and MQP heat treatments increased by 16.4%, 44.3% and 41.0%, respectively. The wear mechanism was a synergistic effect of the adhesive wear mechanism and the abrasive wear mechanism. The adhesive wear mechanism was mainly considered in the MQPT-treated sample to reduce the wear rate attributed to high-proportion retained austenite and the existence of wear debris with a W element on the surface of the wear track. However, the abrasive wear mechanism could exist in the other samples because of a lot of thick, brittle M7C3, thereby resulting in a higher wear rate due to immediate contact between the designed material and the counterpart.

As one of the common abiotic stresses, chilling stress has negative effects on rice growth and development. Minimization of these adverse effects through various ways is vital for the productivity of rice. Nanoparticles (NPs) serve as one of the effective alleviation methods against abiotic stresses. In our research, zinc oxide (ZnO) NPs were utilized as foliar sprays on rice leaves to explore the mechanism underlying the effect of NPs against the negative impact of chilling stress on rice seedlings. We revealed that foliar application of ZnO NPs significantly alleviated chilling stress in hydroponically grown rice seedlings, including improved plant height, root length, and dry biomass. Besides, ZnO NPs also restored chlorophyll accumulation and significantly ameliorated chilling-induced oxidative stress with reduced levels of H2O2, MDA, proline, and increased activities of major antioxidative enzymes, superoxide dismutase (SOD), catalase (CAT), and peroxidase (POD). We further found that foliar application of ZnO NPs induced the chilling-induced gene expression of the antioxidative system (OsCu/ZnSOD1, OsCu/ZnSOD2, OsCu/ZnSOD3, OsPRX11, OsPRX65, OsPRX89, OsCATA, and OsCATB) and chilling response transcription factors (OsbZIP52, OsMYB4, OsMYB30, OsNAC5, OsWRKY76, and OsWRKY94) in leaves of chilling-treated seedlings. Taken together, our results suggest that foliar application of ZnO NPs could alleviate chilling stress in rice via the mediation of the antioxidative system and chilling response transcription factors.

The single sonotrode-generated ultrasonic field cannot fully spread the whole volume of large-scale Al alloy melt. Then, the effective volume of Al alloy melt processed by ultrasound is very limited. Thus, single sonotrode does not completely satisfy the casting of large-scale Al alloys. Scalable power ultrasounds provide an alternative way for this dilemma. However, only the optimal configuration of scalable power ultrasounds lead to a high efficiency during casting. In the present work, numerical simulation of ultrasonic field within the large-scale Al alloy melts was carried out for three cases, i.e. single sonotrode, three parallel sonotrodes, and three non-parallel sonotrodes that were configured in various ways. Simulation work mainly focused on investigating (a) the three dimensional (3D) distribution of acoustic pressure under different configurations, (b) the 2D distribution of acoustic pressure along each sonotrode’s axis, (c) the 1D distribution of acoustic pressure along the central axis of large-scale Al alloy melts, and (d) the mean acoustic energy density and the cavitation zones as well. Meanwhile, the 3D dynamic evolution of acoustic pressure fields for different configurations was also analyzed in one cyclic vibration time. Compared with single sonotrode, three scalable sonotrodes (when configured in an appropriate way) enable to generate larger high-pressure zones, increase the mean acoustic energy density, and enlarge the volume fraction of potential cavitation zones. The present work raises insights for the configuration and optimization of scalable sonotrodes for casting the large-scale metallic materials, like Al alloy.

The xantha trait of a yellow leaf rice mutant (HYB), controlled epigenetically by elevated CHG methylation of the genomes uncoupled 4 (OsGUN4) promoter, has reduced chlorophyll content, altered tetrapyrrole biosynthesis, and deregulated transcription of photosynthesis-associated nuclear genes (PhANGs) compared to its wild-type progenitor Longtefu B (LTB). In the present study, we identified a suppressor mutant (CYB) of HYB and characterized its genetic, molecular, and physiological basis of the mutant phenotype. We found that the light-green phenotype of CYB was caused by a suppressor mutation in an unknown gene other than OsGUN4. Compared to HYB, the CHG methylation in the OsGUN4 promoter was reduced, while OsGUN4 transcript and protein abundance levels were increased in CYB. The contents of total chlorophyll and its intermediate metabolites (except protoporphyrin IX) in CYB plants were intermediate between HYB and LTB. The expression levels of 30 genes involved in tetrapyrrole biosynthesis in CYB were all partially reverted to those of LTB, so were the PhANGs. In summary, a suppressor mutation caused the reversion of the xantha trait via reducing CHG methylation in OsGUN4 promoter.

The oxidation kinetics and behavior of vanadium carbide particle-reinforced Fe-based composites (VCps-Fe-MC) were investigated at 600, 800, and 950 °C. The microstructure of the surface and cross-section of the oxidation layer was characterized by scanning electron microscope (SEM). The composition of the surface of the oxide scales was examined by X-ray diffraction (XRD) and energy-dispersive spectroscopy (EDS). The micro hardness of the specimens was measured by a micro-hardness tester after a high-temperature treatment and subsequent air cooling. The results showed that the growth of the oxide scales on the VCps-Fe-MC followed a parabolic curve with an increase in the oxidation time. In addition, the weight gain increased with the oxidation temperature during the same period. Different oxide scales and oxidation rates occurred in some regions due to different textures. The minimum oxidation rate was in the austenite region because of a high silicon and chromium contents. At the same time, severe cracking and large shedding of the oxide scales were discovered due to growth stress and thermal stress. These defects can provide channels for oxygen diffusion. Based on the micro-hardness values, temperatures greater than 900 °C can be regarded as austenitizing temperatures during heat treatment to improve the mechanical properties and the wear resistance.

OsIPK1 encodes inositol 1,3,4,5,6-pentakisphosphate 2-kinase, which catalyzes the conversion of myo-inositol-1,3,4,5,6-pentakisphosphate to myo-inositol-1,2,3,4,5,6-hexakisphosphate (IP6) in rice. By clustered regularly interspaced short palindromic repeats (CRISPR) and CRISPR-associated protein (Cas9)-mediated mutagenesis in the 3rd exon of the gene, three OsIPK1 mutations, i.e., osipk1_1 (a 33-nt deletion), osipk1_2 (a 1-nt deletion), and osipk1_3 (a 2-nt deletion) were identified in T0 plants of the rice line Xidao #1 (wild type, WT). A transfer DNA free line with the homozygous osipk1_1 mutation was developed; however, no homozygous mutant lines could be developed for the other two mutations. The comparative assay showed that the osipk1_1 mutant line had a significantly lower level of phytic acid (PA, IP6; −19.5%) in rice grain and agronomic traits comparable to the WT. However, the osipk1_1 mutant was more tolerant to salt and drought stresses than the WT, with significantly lower levels of inositol triphosphate (IP3), reactive oxygen species (ROS) and induced IP6, and higher activities of antioxidant enzymes in seedlings subjected to these stresses. Further analyses showed that the transcription of stress response genes was significantly upregulated in the osipk1_1 mutant under stress. Thus, the low phytic acid mutant osipk1_1 should have potential applications in rice breeding and production.

In situ TiB2/2A14 composites with a 3% volume fraction were prepared by mixing salt reaction and high energy ultrasound. The effects of high-intensity ultrasonic on the microstructure and mechanical properties of TiB2/2A14 composites were systematically investigated. The microstructures of the composites were analyzed using scanning electron microscopy (SEM) and electron backscattered diffraction (EBSD). The phase composition was examined by X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The results showed that after introducing ultrasonic vibration into the melt, due to the cavitation and acoustic streaming effect, the particle agglomerations were significantly reduced and particles of different sizes were evenly dispersed in the matrix. With ultrasonic vibration treatment of 120 s, the agglomerations were basically eliminated, and the particles were uniformly distributed to the most. The yield strength, tensile strength and elongation of the composites were increased by 53%, 21% and 30%, respectively, compared with that without ultrasonic vibration treatment (UVT).

The structure and composition of large-scale Al−Cu alloy ingots are inhomogeneous, and the segregation of (especially) elemental Cu negatively affects the uniformity and stability of the subsequent components. In this work, four ultrasonic generators were used to manipulate solidification/microstructures of cylindrical Al−Cu ingots (1250 mm in diameter; 3500 mm in length). The influence of ultrasonic configuration on both solidification microstructures and solute macrosegregation was investigated by changing the position parameters of generators for a fixed power. The results revealed that when the ultrasound is applied close to the center (I) from the 1/2 radius (II), the grain structure of the center undergoes significant refinement, degree of positive segregation in the center can be reduced, segregation index decreased from 0.2 to 0.15, and range of positive segregation in the center decreased from 200 to 150 mm. The segregation of elemental Cu was weakened by the combined effects of the ultrasound on the flow, heat transfer, and grain movement.

In this work, a fast water-responsive shape memory hybrid polymer based on thermoplastic polyurethane (TPU) was prepared by crosslinking with hydroxyethyl cotton cellulose nanofibers (CNF-C) and multi-walled carbon nanotubes (CNTs). The effect of CNTs content on the electrical conductivity of TPU/CNF-C/CNTs nanocomposite was investigated for the feasibility of being a strain sensor. In order to know its durability, the mechanical and water-responsive shape memory effects were studied comprehensively. The results indicated good mechanical properties and sensing performance for the TPU matrix fully crosslinked with CNF-C and CNTs. The water-induced shape fixity ratio (Rf) and shape recovery ratio (Rr) were 49.65% and 76.64%, respectively, indicating that the deformed composite was able to recover its original shape under a stimulus. The TPU/CNF-C/CNTs samples under their fixed and recovered shapes were tested to investigate their sensing properties, such as periodicity, frequency, and repeatability of the sensor spline under different loadings. Results indicated that the hybrid composite can sense large strains accurately for more than 103 times and water-induced shape recovery can to some extent maintain the sensing accuracy after material fatigue. With such good properties, we envisage that this kind of composite may play a significant role in developing new generations of water-responsive sensors or actuators.

In this study, castings of TiC nanoparticle reinforced 2219 aluminum matrix composites with different TiC nanoparticle contents (0, 0.5, 0.9, 1.3, and 1.7 wt.%) prepared using an ultrasound-assisted stirring technology were deformed by multidirectional forging at 510 °C followed by T6 aging treatment. The microstructural evolution and mechanical properties of the 2219 alloy and its composites were investigated and compared. Optical microscopy and scanning electron microscopy revealed that the composite with 0.9 wt.% TiC nanoparticle content possessed finer grains and the lowest amount of Al2Cu phases. The electron backscattered diffraction (EBSD) was used to characterize the sub-grains. The precipitation microstructures of the 2219 alloy and composites with different nanoparticle contents were characterized by differential scanning calorimetry and transmission electron microscopy. It was found that 0.9 wt.% TiC/2219 nanocomposites contained the highest amount of θ″ and θ′ phases with shorter lengths. This might imply that the nanoparticles uniformly dispersed in the matrix could facilitate the precipitation of θ″ and θ′ phases during aging. Thus, the 0.9 wt.% TiC/2219 nanocomposite showed the best mechanical properties. The ultimate tensile strength, yield strength, and elongation of the 0.9 wt.% TiC/2219 nanocomposite increased by 24.2, 46.1, and 37.2%, respectively, compared to those of the 2219 alloy.

Oxide films or inclusions can reduce the continuity and integrity of materials and they always lead to a significant reduction in the mechanical properties of an aluminum alloy. They can greatly reduce the plastic flow behavior of materials, thus affecting the subsequent processing performance. Therefore, an effective ultrasonic assisted preparation technology has been applied to industrial manufacturing of large-scale aluminum alloy ingots (with diameter: Φ = 1250 mm and height: h = 3750 mm). However, the mechanisms of ultrasonic purification on the large-scale ingots are not clear. Therefore, a number of aluminum alloy casting experiments were carried out to produce a conventional hot top semi-continuous ingot (CHTI) and an ultrasonic hot top semi-continuous ingot (UHTI) in this work. The microstructures of CHTI and UHTI were analyzed by optical microscopy (OM) and scanning electron microscopy (SEM). The results indicated that there were some oxide film defects in the CHTI but some finely dispersed inclusion particles were discovered in the UHTI. The X-ray diffraction (XRD) data showed that the component of inclusion was Al2O3. According to the different cavitation effects of the different areas of the molten aluminum, the process of ultrasonic purification was divided into three periods and the mechanisms in each period were separately studied.

The work described in this paper dealt with the effect of ultrasonic vibration on the solidification of 7050 aluminum alloy. Two experiments were carried out through introducing ultrasound into the semi-continuous direct-chill (DC) casting of aluminum alloy and into alloy solidifying in a crucible, respectively. Results show that ultrasonic vibration can refine grains in the whole cross-section of a billet in the first experiment and is able to increase the cooling rate within the temperature range from 625 °C to 590 °C in the other one. The mechanism of particle resonance caused by ultrasonic vibration was illustrated on the basis of theoretical analysis of the kinetics and energy conversion during the solidification. It is demonstrated that the kinetic energy of resonant particles are mainly from the latent heat energy of solidification, which can shorten the cooling time, inhibit the crystal growth and then lead to the grain refinement.