Explore the vast range of titles available.

Sphagnum bogs possess irreplaceable ecological and economic value, and they are scarce in China, with a fragmented distribution. Based on 19 high-resolution bioclimatic environmental datasets and 71 bog center point locations, we employed a maximum entropy model (MaxEnt) to reconstruct and predict the spatial-temporal geographical distribution patterns of Sphagnum bogs from the last interglacial (LIG) period to two typical CO2 representative concentration pathway scenarios (RCP2.6, RCP8.5) in the future. We further computed the migratory paths of the distribution center points. Finally, a jackknife test was used to uncover the crucial environmental factors restricting the geographical distribution of the bogs. Our data indicated that the MaxEnt niche model had a high simulation precision with an area under the ROC curve value of 0.957. Spatially, the suitable bog habitats are currently centralized in northeastern China, including the Greater Khingan Mountains, the Lesser Khingan Mountains, and the Changbai Mountains, as well as peripheral areas of the Sichuan Basin. Temporally, the contours of Sphagnum bogs were similar to the present and rendered from the last glacial maximum (LMG) period, and had much more total area than the current. The total area in LIG was nearly the same as the current because of the similar climate. It was worth noting that there would be a reduction of the total area in the future. Loss of area occurred at the edges of bogs, especially under RCP8.5. The distribution center of bogs will shift to the northwest in the immediate future. The precipitation of driest month, the mean temperature of warmest quarter and the precipitation of warmest quarter were identified as crucial climatic factors affecting the distribution of Sphagnum bogs. Overall, our research provides scientific evidence for the long-term protection and effective management of these rare, precious natural resources and suggestions for in situ conservation.

Carrying out the constitutive model research of melt-cast explosives is helpful to evaluate the safety of explosives, optimize the performance design, guide the material research and improve the accuracy of engineering design. In this paper, the Karagozian & Case model is applied to melt-cast explosives for the first time. Taking the 3,4-dinitropyrazole-based melt-cast explosive as an example, quasi-static compression mechanical property, dynamic compression mechanical property and quasi-static Brazilian disc tests of its typical formulation were carried out by the universal materials testing machine and the split Hopkinson pressure bar test setup. Based on the test results, the parameters of the Karagozian & Case model were calibrated. Using the calibrated model parameters, the mechanical responses of the 3,4-dinitropyrazole-based melt-cast explosive under dynamic impact, quasi-static compression and triaxial confining pressure were calculated. The results show that the model’s capability in describing the complete mechanical behavior of melt-cast explosives, from elastic deformation through damage evolution to ultimate failure. The Karagozian & Case model effectively reproduces the material’s strain-rate sensitivity and accurately captures the transition from brittle to ductile behavior under confining pressure. Consequently, the Karagozian & Case model is established as an effective tool for predicting the mechanical response of melt-cast explosives under various loading conditions, and valuable insights are provided for safety evaluation and performance optimization in engineering applications.

Optimizing field cropping practices to improve nitrogen use efficiency is imperative to promote intensive and sustainable wheat production. As a cultivation method commonly adopted in arid and semi-arid regions globally, the ridge–furrow mulching system (RFMS) is capable of efficiently harvesting rainfall, reduce evaporation losses, enhancing soil moisture levels in the root zone, and boosting crop productivity. However, the combined effects of varying ridge–furrow ratios (RD), ridge heights (RH), and nitrogen application rates (RN) on nitrogen fertilizer bias productivity (PFPN) under the influence of climatic conditions, soil types, and field management practices remain poorly understood due to a lack of systematic evaluation. This study conducted a meta-analysis of 462 comparative datasets from 98 research projects to reveal the interactive effects of RFMS and nitrogen fertilizer across climatic gradients. The results showed that RH, RD, and RN increased by 23.78%, 22.37%, and 23.07% respectively (p < 0.05), with the most significant enhancement of PFPN being demonstrated by RH. The most significant improvement in PFPN was observed when RD = 1:1, R < 10 cm, and RN > 200 kg∙hm[sup.−2], with PFPN increasing by 27.7%, 29.50%, and 29.32% respectively (p < 0.05). Climatic and soil physico-chemical factors and field management practices are the key factors influencing the RFMS. When average annual evapotranspiration (AE) < 1000, RN > 200 has the best effect on nitrogen utilization efficiency, while under the condition of AE > 1500, RN < 100 is more effective. In terms of mulching strategy, full mulching of ridges and furrows is recommended in areas with severe drought and low temperatures, while mulching only ridges or furrows is more appropriate in areas with relatively mild climate. The present study provides a scientific basis for the optimal design of ridge–furrow mulching configuration and nitrogen application level. This is achieved by considering climatic conditions, soil fertility, and field management in agro-ecosystems in arid and semi-arid areas.

Exploring the coupling characteristics of regional water resources and food security helps to promote the sustainable development of grain production and is of great significance for achieving global food security. From the aspects of regional “water supply”, “water use” and “water demand”, the coupling characteristics of water resources and food security were systematically revealed; the new challenges faced by regional food security from the perspective of water resources were clarified; and effective ways to promote the utilization of regional water resources and the sustainable development of grain production were explored. This paper took Northwest China, which is the most arid region, where water-resource utilization and food security are in contradiction, as the research area. The water-resource load index, the water footprint of grain production and the water-consumption footprint were used to quantify the regional water-resource pressure index, as well as the residential grain-consumption types, population urbanization, the industrial-grain-processing industry and their corresponding water-consumption footprints from 2000 to 2020. The coupling characteristics of water resources and food security were systematically revealed. The results showed the following: (1) In 2000–2020, the water-resource load index increased from 4.0 to 10.7, and the load level increased from III to I. At the same time, agricultural water resources were largely allocated elsewhere. (2) During the period, the food rations showed a significant decreasing trend, and the average annual reduction was 3.4% (p < 0.01). The water footprint of animal products increased, particularly for beef and poultry (the average annual growth rates were 9.9% and 6.3%, respectively). In addition, the water footprint of industrial food consumption increased by 297.1%. (3) With the improvement of the urbanization level, the water-consumption footprint increased by 85.9%. It is expected that the water footprint of grain consumption will increase by 39.4% and 52.3% by 2030 and 2040, respectively. Exploring how to take effective measures to reduce the water footprint to meet food-security needs is imperative. This study proposed measures to improve the utilization efficiency of blue and green water and reduce gray water and the grain-consumption water footprint from the aspects of regional planting-structure optimization potential, water-saving irrigation technology, dietary-structure transformation and virtual water trade; these measures could better relieve the water-resource pressure and promote the sustainable development of grain production and water-resource utilization.

Understanding the greenhouse gas emissions mechanism from the agricultural soils is essential to reach an agricultural system with a lower impact on the environment. The cultivation practices in combination with deficit irrigation have been used in a dry-land farming system to modify the soil water status. However, few research works have been focused on plastic film with deficit irrigation regimes on global warming potential (GWP), greenhouse gas intensity (GHGI), and biomass productivity under simulated rainfall conditions. In the current study, a 2-year study was carried out in a rainproof mobile shelter to study the potential role of two cultivation practices (i.e., furrow with plastic mulching on ridges, RF; and conventional flat cultivation, TF) in combination with two deficit irrigation regimes (i.e., 150 and 75 mm) and three simulated rainfall (i.e., 1, 275 mm; 2, 200 mm; and 3, 125 mm). . We found that RF2 150 treatment was more effective in improving the soil water content, soil respiration rate, and winter wheat production and significantly reduced (39.2%) the GHGI and GWP than TF2 150 treatment. The RF2 150 treatment improved soil moisture and significantly increased (18.9%) grain yield, (11.1%) biomass, (75.8%) WUE g , and (64.1%) WUE b of winter wheat and largely mitigated GWP and GHGI. The RF system with 150-mm deficit irrigation regime plays a significant role in increasing the biomass productivity and soil respiration rate and minimizing the seasonal greenhouse gas fluxes, GHGI, and field ET rates under 200-mm precipitation condition. Compared with TF practice, the plastic film mulching on ridges and furrow on the planting zone could significantly improve biomass and WUE and reduce N 2 O, CO 2 , and CH 4 emissions. The RF2 150 treatment should be very good water-saving approach and a powerful tool to decrease GHGI and GWP via increased biomass, WUE, soil respiration rate, and wheat yields under a dry-land farming system.

This paper presents decentralized solutions for pursuit-evasion problems involving high-order integrators with intracoalition cooperation and intercoalition confrontation. Distinct error variables and hyper-variables are introduced to ensure the control strategies to be independent of the relative velocities, accelerations and higher order information of neighbors. Consequently, our approach only requires agents to exchange position information or to measure the relative positions of the neighbors. The distributed strategies take into consideration the goals of intracoalition cooperation or intercoalition confrontation of the players. Furthermore, after establishing a sufficient and necessary condition for a class of high-order integrators, we present conditions for capture and formation control with exponential convergence for three scenarios: one-pursuer-one-evader, multiple-pursuer-one-evader, and multiple-pursuer-multiple-evader. It is shown that the conditions depend on the structure of the communication graph, the weights in the control law, and the expected formation configuration. Finally, the effectiveness of the proposed algorithm is demonstrated through simulation results.

Cabbage cultivation has been observed to significantly hinder the growth of subsequent crops in the cold, arid regions of Shanxi Province. To investigate the allelopathic effects of cabbage ( Brassica oleracea L. var. Capitata L.) on seed germination and seedling growth of three crops commonly cultivated in such areas, we studied the effects of water extracts from air-dried cabbage leaves on cocozelle, kidney bean, and corn. Experiments were conducted using both petri dish filter paper and pot culture methods to simulate natural conditions. The results indicated that cabbage leaf water extracts at concentrations of 0.01-0.04 g·mL -1 significantly inhibited seed germination. At higher concentrations (0.06-0.08 g·mL -1 ), the extract markedly suppressed seedling growth in all three crops (p < 0.05), with the degree of inhibition increasing alongside concentration. Radicle elongation in cocozelle and corn was more strongly inhibited than germ elongation at the same extract concentration, In contrast, kidney bean showed greater inhibition of germ elongation than radicle elongation at 0.04 g·mL -1 . Malondialdehyde (MDA) content was elevated in kidney bean and corn seedlings treated with cabbage extract, indicating oxidative stress. At extract concentrations of 0.06-0.08 g·mL -1 , antioxidant enzyme activities, such as antioxidase superoxide dismutase (SOD), peroxidase (POD) and catalase (CAT) were enhanced in all three crops. The comprehensive allelopathic inhibition followed the order: cocozelle > corn > kidney bean. The differences appear to be related to the changes in MDA content and antioxidant enzyme activity. Based on these findings, rotating cabbage and kidney bean may help reduce negative allelopathic effects. It is also recommended to remove the entire aboveground portion of cabbage during harvest to reduce allelochemical residues in the soil and minimize their inhibitory impact on subsequent crops.

Background Myocardial infarction (MI) is a severe disease that often associated with impaired angiogenesis and increased myocardial apoptosis. Mesenchymal stromal cells (MSCs) have been a promising candidate for treating myocardial infarction. However, functional heterogeneity of MSCs leads to inconsistent therapeutic efficiency and the current MSCs-based therapy lacks the concept and implementation of precision medicine. In this study, we compared the cardioprotective effect of UCMSCs and ADMSCs targeting the angiogenesis in a mouse MI model and screened out optimum MSCs candidate for precise clinical application. Methods The gene expression profiles of UCMSCs and ADMSCs were investigated through RNA sequencing analysis. To compare their angiogenic potential, we performed tube formation assay, Matrigel plug assays, and aortic ring assay, and analyzed pro-angiogenic genes via qPCR. Subsequently, UCMSCs and ADMSCs were respectively injected into myocardium after MI surgery in mice. On day 28 post-MI, echocardiography was performed to assess cardiac function. Histological analysis was performed to assess MSCs retention, angiogenesis, and myocardial apoptosis. Additionally, the anti-apoptosis effects mediated by MSCs were further evaluated using flow cytometry in hypoxia H9C2 and HL-1 cells. Results The RNA sequencing analysis revealed differences in gene expression related to angiogenesis and apoptosis pathways between UCMSCs and ADMSCs. UCMSCs presented greater pro-angiogenesis activity than ADMSCs in vitro and in vivo. Both of UCMSCs and ADMSCs improved cardiac function, decreased infarction area and inhibited cardiomyocyte apoptosis while promoting angiogenesis post-MI in mice. Notably, ADMSCs exerted a better cardioprotective function than UCMSCs and stronger anti-apoptotic effect on residual cardiomyocytes. Conclusions The protection of residual cells survival played a more prominent role than angiogenesis in MSCs-based therapy for acute MI. Our study provides new insights into therapeutic strategies and suggests that the optimal type of MSCs can be screened based on their tissue heterogeneity for precise clinical applications in acute MI.

The ridge furrow (RF) rainwater harvesting system is an efficient way to enhance rainwater accessibility for crops and increase winter wheat productivity in semi-arid regions. However, the RF system has not been promoted widely in the semi-arid regions, which primarily exist in remote hilly areas. To exploit its efficiency on a large-scale, the RF system needs to be tested at different amounts of simulated precipitation combined with deficit irrigation. Therefore, in during the 2015-16 and 2016-17 winter wheat growing seasons, we examined the effects of two planting patterns: (1) the RF system and (2) traditional flat planting (TF) with three deficit irrigation levels (150, 75, 0 mm) under three simulated rainfall intensity (1: 275, 2: 200, 3: 125 mm), and determined soil water storage profile, evapotranspiration rate, grain filling rate, biomass, grain yield, and net economic return. Over the two study years, the RF treatment with 200 mm simulated rainfall and 150 mm deficit irrigation (RF2 ) significantly ( < 0.05) increased soil water storage in the depth of (200 cm); reduced ET at the field scale by 33%; increased total dry matter accumulation per plant; increased the grain-filling rate; and improved biomass (11%) and grain (19%) yields. The RF2 treatment thus achieved a higher WUE (76%) and RIWP (21%) compared to TF. Grain-filling rates, grain weight of superior and inferior grains, and net economic profit of winter wheat responded positively to simulated rainfall and deficit irrigation under both planting patterns. The 200 mm simulated rainfall amount was more economical than other precipitation amounts, and led to slight increases in soil water storage, total dry matter per plant, and grain yield; there were no significant differences when the simulated rainfall was increased beyond 200 mm. The highest (12,593 Yuan ha ) net income profit was attained using the RF system at 200 mm rainfall and 150 mm deficit irrigation, which also led to significantly higher grain yield, WUE, and RIWP than all other treatments. Thus, we recommend the RF2 treatment for higher productivity, income profit, and improve WUE in the dry-land farming system of China.

In semi-arid areas of China, the ridge-furrow mulched with plastic film (RF) cultivation system is a common water-saving agricultural technique where the shortage of water resources has become a serious problem. Therefore, we aimed to explore whether this cultivation is actually an improvement over the traditional flat planting (TF) method while testing two deficit irrigation (150, 75 mm) levels to grow winter wheat. Furthermore, we examined the responses of the anti-oxidative defence system and photosynthetic capacity of winter wheat flag leaves under three simulated rainfall (275, 200 and 125 mm) conditions. The results showed that the RF system with 150 mm deficit irrigation and 200 mm simulated rainfall condition (RF2150) treatment raised soil water content (%) at the jointing and flowering stages and achieved higher net photosynthesis rates (Pn) in flag leaves. Furthermore, such improvements were due to the reduction of malondialdehyde (MDA) content and oxidative damage during different growth stages of winter wheat. The RF2150 treatment significantly increased the activities of superoxide dismutase (SOD); peroxidise (POD), catalase (CAT) and ascorbate peroxidase (APX) and the content of soluble protein (SP) during different growth stages of winter wheat. Furthermore, RF2150 treatment attained the highest value at the flowering stage, while also exhibiting significant declines in contents of proline, MDA, H2O2 and O2 in flag leaves. The higher free H2O2 and O2 scavenging capacity and better anti-oxidative enzyme activities under the RF2150 treatment were due to the lower level of lipid peroxidation, which effectively protected the photosynthetic machinery. The net photosynthetic rate of flag leaves was positively correlated with SOD, POD, CAT, APX and SP activities, and negatively correlated with proline, MDA, H2O2 and O2 contents. We concluded that the RF2150 treatment was the better water-saving management strategy because it significantly delayed flag leaf senescence and caused the increases in SWC, WUE, Pn, antioxidant enzyme activities and grain yield of winter wheat grown in semi-arid regions of China.