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Tiantian Hu,1– 3,* Hongxia Wang,4,* Chengzheng Xiang,1– 3 Jianfei Mu,1– 3 Xin Zhao1– 3 1Chongqing Collaborative Innovation Center for Functional Food, Chongqing University of Education, Chongqing, People’s Republic of China; 2Chongqing Engineering Research Center of Functional Food, Chongqing University of Education, Chongqing, People’s Republic of China; 3Chongqing Engineering Laboratory for Research and Development of Functional Food, Chongqing University of Education, Chongqing, People’s Republic of China; 4Department of Paediatrics, Haikou Affiliated Hospital of Central South University Xiangya School of Medicine (Haikou People’s Hospital), Haikou, Hainan, People’s Republic of China*These authors contributed equally to this workCorrespondence: Xin Zhao Tel +86-23-6265-3650Email zhaoxin@cque.edu.cnIntroduction: Lactobacillus acidophilus is widely used as probiotic supplement in functional foods due to its beneficial regulatory effects on host, such as immune regulation, anti-inflammatory, and antioxidant activities.Aim: This study aimed to determine the preventive effect of Lactobacillus acidophilus XY27 (L. acidophilus XY27) on colitis induced by dextran sodium.Methods: The mice were randomly divided into five groups. Except for the control group, the other four groups were induced for ulcerative colitis (UC) with dextran sodium sulfate (DSS), and three groups in DSS-groups were treated with L. acidophilus XY27, L. bulgaricus, and salicylazosulfapyridine. The weight change, DAI score, colon length, and length to weight ratio were tested. The oxidation index and the levels of inflammatory cytokines in the serum were measured. Subsequently, the gene expression levels of inflammatory factors in the colon tissue were determined by the Real-Time quantitative polymerase chain reaction (qRT-PCR) method.Results: The results showed that the mice in the L. acidophilus XY27 group performed better in terms of weight, DAI score, colon length, and length to weight ratio or colonic pathological sections compared with the DSS-induced group. Further, the levels of tumor necrosis factor α (TNF-α), Interleukin-6 (IL-6), Interleukin-12 (IL-12) and Interleukin-1β (IL-1β), malondialdehyde (MDA) content, and myeloperoxidase activity in the serum of UC mice treated with L. acidophilus XY27 significantly decreased, while the levels of Interferon-γ (IFN-γ), Interleukin-10 (IL-10), Catalase (CAT), and total superoxide dismutase (SOD) significantly increased. The gene expression levels of Ets-like transcription factor-1 (EIK-1), IL-12, IL-1β, Cyclooxygenase 2 (COX-2), TNF-α, Escherichia coli, Lipopolysaccharide (LPS), and p100 in the colon significantly decreased while those of tight junction protein 1 (ZO-1), nuclear factor kappa B (NF-kB), p53, and NF-kappa-B inhibitor alpha (IκB-α) increased in the L. acidophilus XY27 group.Conclusion: The results of the experiment suggested that L. acidophilus XY27 prevented colitis and alleviated symptoms in mice with DSS-induced UC, and also repaired the intestinal barrier function.Keywords: dextran sodium sulfate, Lactobacillus acidophilus XY27, Lactobacillus bulgaricus, ulcerative colitis

Objective: To observe the clinical efficacy of electroacupuncture treatment for primary dysmenorrhea. Methods: In total 75 patients with primary dysmenorrhea were randomized into electroacupuncture with point injection group (37 patients), and electroacupuncture group (38 patients). Cox Menstrual Symptom Scale (CMSS) and Visual Analogue Scale (VAS) were observed before and after three treatment interventions, and the clinical efficacies were compared. Results: The total effective rates were 91.9% and 86.8%, and the difference was not significant ([Formula: see text]). Conclusions: Electroacupuncture with point injection and electroacupuncture are effective methods in treating primary dysmenorrhea, and the difference between the two groups is not statistically significant.

In this article, the preventive and protective effect of a new

The transgenerational effect assessment linked to epigenetic analysis of environmental pollutants on eco (toxico)logical relevant species is regarded as a potential future risk-assessment tool. As an organotin acaricide widely used in China, azocyclotin can lead to endocrine disrupting effect on directly exposed environmental organisms, but whether it has transgenerational negative impact remains unknown. In order to illustrate this issue, in the present study, zebrafish, an aquatic model animal, was exposed to azocyclotin at less than μg/L level in a time span of embryonic stage to adult stage. Subsequently, the developmental and reproductive endocrine disrupting effects of azocyclotin on exposed F0 and unexposed offspring (F1 and F2) were evaluated. Result indicated that parentally exposed to 0.36 μg/L azocyclotin induced embryonic toxicity to unexposed offspring, and significantly (p 0.05) reduced body weight (by 8.5%-13.9%), whole body length (by 4.8%-14.3%), hepatosomatic index (by 15.6%-24.3%), gonadosomatic index (by 5.3%-17.1%), egg production (by 19.5%-25.4%), estradiol content (47.0%-65.0%) and proportion of mature germ cells (by 29.3%-41.0% and 39.2%-47.7% for late oocytes and spermatozoa, respectively) in adults of F0 and offspring. Additionally, azocyclotin decreased the contents of 5-methycytosine in gonads of unexposed offspring (by 9.9%-38.6%, p 0.05), led to genome-wide gene up-regulated expression bias and genomic DNA hypomethylation tendency in unexposed offspring. Moreover, based on the level of differentially methylated cytosine in promoter regions/gene body regions, it was found totally 5331/11,170 (in F1) and 3808/7507 (in F2) differentially expressed genes were closely related with differentially methylated genes (r 0.6). The present study provided a primary evidence that prolonged exposure to low dose azocyclotin induced inter- and transgenerational endocrine disrupting effects on zebrafish probably linked to transcriptomic and DNA methylomic alterations.

The extensively studied cAMP-dependent protein kinase A (PKA) is involved in the regulation of critical cell processes, including metabolism, gene expression, and cell proliferation. Therefore, PKA has been viewed increasingly as potential target for variety of drugs and environmental endocrine disruptors. Consequentially, the preparation of PKA protein became an important initial step for the subsequent exploration of PKA's character in endocrine disrupting effects of pesticides. To investigate PKA protein, which is potential to be the environmental endocrine toxicity target of triazole fungicides, a strategy to heterologously express protein kinase A catalytic alpha subunit of human (hPKAcα) and zebrafish (zPKAcα) in Escherichia coli (E. coli) BL21(DE3) host cells was demonstrated. After optimizing conditions and protein purification, we successfully obtained enzymatically active hPKAcα and zPKAcα. Western blot analysis indicated that the recombinant hPKAcα and zPKAcα still retained their characteristic antigenicity and binding activity, while in vitro kinase activity assays revealed that the recombinant hPKAcα and zPKAcα maintained enzyme activity. By in silico methods including homology modelling and molecular docking, the affinity of ligands and the models of hPKAcα and zPKAcα were further tested. The present study offered a valuable method to achieve the prokaryotic expression of a eukaryotic protein kinase and laid a foundation to facilitate further investigation of toxicological target of triazole pesticides.

Deltamethrin (DM), a type II pyrethroid insecticide, is widely used to control agricultural pests. However, its excessive use exerts a detrimental effect on the ecological environment and human health, indicating the need to study its potential risks in detail. In the present study, zebrafish embryos were exposed to varying concentrations of DM (0.1, 1, 10, and 25 μg/L) for 96 h to assess the alterations in the transcript levels of proteins of the estrogenic and dopaminergic pathways. In addition, its effect on zebrafish locomotor activity was studied. The mRNA expression of cyp19a1b, erα, erβ2, fshr, gnrh2, gnrhr3, vtg3, dat, and dr1 significantly changed after exposing the embryos to DM. Deltamethrin at 10 and 25 μg/L significantly reduced the average swimming speed of zebrafish larvae. In addition, embryos injected with zebrafish estrogen receptor α (erα) and β (erβ) morpholinos and co-exposed to 25 μg/L DM for 96 h showed reduced expression of vtg3 mRNA compared to embryos exposed to 25 μg/L DM only. The locomotor activity of erα and erβ knockdown zebrafish following DM exposure was increased significantly when compared with that of larvae exposed to 25 μg/L DM only. Our results demonstrated that DM altered the locomotor activity of zebrafish larvae and the transcript levels of the components of estrogenic and dopaminergic pathways; erα and erβ knockdown weakened these effects.

A field experiment was carried out to investigate effect of nitrogen (N) supply method on root growth and its correlation with the above-ground parts in maize (Zea mays L.) under alternate partial root-zone irrigation (APRI) at Wuwei, northwest China in 2012 and 2014. The treatments included alternate N supply, conventional N supply and fixed N supply under APRI (designated AN, CN and FN, respectively), with an additional CN fertilizer treatment coupled with conventional irrigation (CK). Ridges were built in a west-east direction. Root weight density (RWD) in the 0–100 cm soil layer and shoot biomass at the V6, V12, VT, R2 and R6 stages, and grain yield and yield components at the R6 were determined. Results showed that RWD around the plant (i.e. under the plant, south and north of the plant) in the 0–40 cm soil layer varied among different treatments at the VT, R2 and R6 stages. The RWD north and south the plant were comparable during maize growth stages for AN, CN and CK, while FN significantly decreased the RWD of its no N supply side at the three stages and markedly decreased the RWD of its N supply side at the VT. AN and CN significantly increased the RWD, shoot biomass at the three stages, and grain yield compared with FN and CK. Grain yield was positively correlated with RWD in the 0–40 cm soil layer at the three stages. These results suggested that AN and CN produced a relatively uniform distribution of roots and a greater root biomass, which contributed to the enhanced shoot biomass and grain yield of maize under APRI.

Monitoring on urban water environment and analysis of engineering improvement measures are intricate and time-consuming tasks. In previous studies, the integration of hydrodynamic and water quality models and geographical information system (GIS) usually takes three approaches: loose coupling, tight coupling, and full coupling. However, this paper adopted a special loose coupling approach—case-based reasoning (CBR) to develop an integrated decision support system. This was characterized by invoking the case base stored in the GIS platform as the output of the model. The fused capability of model’s water quality predication and strong spatial data processing analysis of GIS can be realized at the same time by integration. The functionality of the integrated system was illustrated through a case study of Chaohu, a medium-sized city in China, which includes case retrieval, result interpretation, and the visual display in the GIS platform. Results verified the feasibility and operability of the developed method. As a useful tool, the integrated decision support system makes it simpler and more convenient for decision makers to make decisions efficiently and quickly.

The protective effect of Lactobacillus plantarum YS3 (LP-YS3) on ulcerative colitis (UC) was assessed using a mouse model of dextran sodium sulfate (DSS)-induced colitis. Different concentrations of LP-YS4 were administered to the experimental mice by daily gavage. Several inflammatory and biochemical indices, such as interleukin-2 (IL-2), interleukin-10 (IL-10), interleukin-6 (IL-6), interleukin-1 beta (IL-1β), tumor necrosis factor-alpha (TNF-α), glutathione (GSH), malondialdehyde (MDA), myeloperoxidase (MPO), and nitric oxide (NO), were examined in mouse serum and colon tissue. The mRNA and protein expression levels of c-Kit, CXC chemokine receptor type 2 (CXCR2), interleukin-8 (IL-8), and stem cell factor (SCF) in mouse colon tissue were assessed using Western blot and quantitative polymerase chain reaction (qPCR) assays. The findings indicated that LP-YS3 remarkably decreased the disease activity index (DAI) of UC mice (p < .05), inhibited colon length shortening induced by UC, and elevated the value of colon weight/length ratio. LP-YS3 could also markedly reduce (p < .05) the activities of MDA, MPO, and NO; while an increase in the GSH content in the colonic tissue of UC mice. Moreover, LP-YS3 remarkably increased (p < .05) the serum level of IL-2 in UC mice, while reduced those of IL-10, IL-6, IL-1β, TNF-α cytokines. qPCR data revealed that LP-YS3 could markedly upregulate the expression levels of c-Kit and SCF, while downregulate those of CXCR2 and IL-8 in the colonic tissue of UC mice (p < .05). LP-YS3 exerted an outstanding protective effect on DSS-induced colitis in C57BL/6J mice, especially at higher concentrations. PRACTICAL APPLICATIONS: Lactobacillus plantarum YS3 is a newly isolated and identified lactic acid bacteria. This study confirmed that L. plantarum YS3 can inhibit colitis and has good probiotic potential, which needs further development and utilization.

In addition to solid legal basis and strong regulatory authority, comprehensive and robust test techniques that reflect real-driving and in-use vehicle emissions are also key elements for achieving ever strict environmental requirements. However, most of the existing portable emissions measurement systems (PEMS) is expensive and bulky, making it impractical to roll out to the vehicle market. The combustion behavior is one of the most important excitation sources of engine vibration and noise emissions. By analyzing structural vibrations, it is possible to assess the in-cylinder combustion conditions, which in turn makes it possible to evaluate the NOx emissions (closely related to combustion temperature) and to achieve cost-effective non-intrusive on-line monitoring of engine in real-driving emissions (RDE). Firstly, a time-frequency reconstruction method is used to estimate second derivative of in-cylinder pressure curve based on measured vibration signal. Good consistency between reconstructed second derivative of in-cylinder pressure curve and measured curve con-firms the rationality of the proposed reconstruction method. Then, a virtual sensing method for NOx emissions using principal component regression (PCR) analysis with reconstructed in-cylinder pressure curve from measured structural vibrations has been presented. The results show that the PCR models have a good prediction of NOx emissions under various operating conditions. The coefficient of determination (R2) between the predicted value and the measured value is 0.971–0.995.

Background The coordinated development of the basic medical insurance system and public health is not only related to the structural soundness of the entire country’s medical and health system, but also related to a country’s initiative in responding to major public health events. Methods This article attempts to endogenously implement health care policies in the health production function, and from the perspective of health benefits, attempts to build a theoretical analysis of framework for the coordinated development of basic medical insurance and public health, revealing the benignly interactive circulation mechanism of the health care system and improving the health benefits of individuals and society realistic path. Results In the field of medical and health services, the establishment of a benign medical and health investment system can promote the improvement of the level of health output and the improvement of the health effectiveness of individuals and society, and thus promote the increase of social and individual health and welfare levels; and promote a virtuous cycle of overall healthy reproduction. Conclusions Under the synergy mechanism, the basic medical insurance policy and public health policy during the new coronary pneumonia should meet the synergy standards. Scientific and reasonable medical and health service policies should not only consider the treatment of new coronary pneumonia patients and group prevention and control, but also pay attention to the coordination of basic medical insurance policies and public health policies, and the coordination of health production and health benefits. The core of policy coordination is to protect both patients with new coronary pneumonia and the general medical and health services of residents.

Chlorpyrifos is a widely used organophosphate insecticide and ubiquitously detected in the environment. However, little attention has been paid to its endocrine disrupting effect to non-target organisms. In the present study, zebrafish was exposed to 13 and 65 μg/L of chlorpyrifos for 7 and 10 days to determine the induced neurotoxicity and the alteration of thyroid metabolism. The 120 h LC50 and LC10 of chlorpyrifos was estimated as 1.35 mg/L and 0.62 mg/L based on the acute embryo toxicity assay, respectively. The acetylcholinesterase (AChE) inhibitory was detected by 13 μg/L chlorpyrifos and could be reversed by the co-exposure of 100 and 1000 μg/L anticholinergic agent atropine. For thyroid hormone level, 13 and 65 μg/L of chlorpyrifos induced increased free T3 levels in 10 dpf (days post-fertilization). The expression of thyroid related genes in 7 and 10 dpf exposed zebrafish were measured by the quantitative Real-Time PCR (qRT-PCR) assay. The mRNA expression of tshba, thrb, crhb, ttr, tpo, ugt1ab and slc5a5 had significant change. However, the alterations of thyroid hormone and mRNA expression could be partly rescued by the addition of atropine. The molecular docking of chlorpyrifos and T3 to the thyroid receptor β in zebrafish using homology modelling and CDOCKER procedures shown weaker binding ability of chlorpyrifos compared to T3. Therefore, we concluded that the disturbance of thyroid signaling in zebrafish might arise from the developmental neurotoxicity induced by chlorpyrifos.

Background In China, income inequality has raised substantially over the last 40 years, especially after21st century.The rise in inequality in China has received considerable attention in academic field. But existing studies have paid more attention to comparative research on the relationship between household income inequality and consumption inequality, and ignored the impact of social welfare changes on household or overall consumption levels during the same period. Methods In this paper, we present an analysis of the trends in inequality of income and consumption in China from 1998 to 2015.Based on the data of China Health and Nutrition Survey(CHNS),we find that household income and consumption inequality have increased substantially over last 30 years.Utilize the inequality of consumption and social welfare and according to the differences in the composition of household consumption, medical consumption is used as the dividing standard to evaluate the inequality of non-medical consumption. In terms of empirical tests, a mixed-panel ols model was constructed to explore the inequality differences in household consumption under non-medical consumption and medical consumption samples. Results First, in terms of consumption inequality, from 1989 to 2015, Chinese household income inequality and consumption inequality showed an increasing trend. Among them, overall consumption inequality was mainly caused by urban and rural consumption inequality. Second,the results show that in terms of overall social welfare, the deterioration of consumption distribution has replaced the growth of social welfare caused by economic growth, and the estimated results under non-medical consumption inequality are less different from the overall. Third, the results of the panel fixed-effect test show that income inequality is the main positive influence factor on consumption inequality, but participation in medical insurance has a negative impact on urban and rural household consumption inequality,illness has a negative impact on household medical inequality and non-medical consumer inequality. Conclusion The result can provide a solid reference for understanding China's consumption inequality and also political implications for the government to weigh efficiency and fairness.From the perspective of consumption policy interventions, it is necessary to promote government departments to better safeguard the health maintenance of healthy or sub-healthy people through health management policies, and promote the cost protection effect of basic medical insurance policies on unhealthy people.

In this paper, a hybrid neural network (HNN) that combines a convolutional neural network (CNN) and long short-term memory neural network (LSTM) is proposed to extract the high-level characteristics of materials for critical temperature (Tc) prediction of superconductors. Firstly, by obtaining 73,452 inorganic compounds from the Materials Project (MP) database and building an atomic environment matrix, we obtained a vector representation (atomic vector) of 87 atoms by singular value decomposition (SVD) of the atomic environment matrix. Then, the obtained atom vector was used to implement the coded representation of the superconductors in the order of the atoms in the chemical formula of the superconductor. The experimental results of the HNN model trained with 12,413 superconductors were compared with three benchmark neural network algorithms and multiple machine learning algorithms using two commonly used material characterization methods. The experimental results show that the HNN method proposed in this paper can effectively extract the characteristic relationships between the atoms of superconductors, and it has high accuracy in predicting the Tc.

Mango (Mangifera indica L.) is one of the widely grown fruit crops and brings remarkable economic benefit in the xerothermic regions of southwest China. However, mango yield and quality can not be guaranteed due to the severe seasonal drought, low precipitation and extensive management of water and fertilizer. To investigate the effects of irrigation amount and fertilizer regime on mango yield, fruit quality, water use efficiency (WUE) and partial fertilizer productivity (PFP), an orthogonal experiment [L9(3)4] was conducted on mango under drip fertigation during 2018–2019. The four factors were irrigation amount (IA) and fertilization rate at the flowering (FⅠ), fruit expansion (FⅡ) and fruit ripening (FⅢ) growth stages. There were three irrigation amounts, i.e., full irrigation (FI: 100%ETc), mild deficit irrigation (DIM: 75%ETc) and severe deficit irrigation (DIS: 50%ETc), and three fertilization rates, i.e., 75 (F75), 50 (F50) and 25 (F25) kg ha−1 using a compound water-soluble fertilizer (N:P2O5:K2O=20%:20%:20%). The results showed the order of factors influencing fruit yield and WUE in terms of their importance was IA, FⅡ, FⅠ and FⅢ, that influencing water, vitamin C and carotenoid contents in fruit was IA, FⅢ, FⅡ and FⅠ, and that influencing soluble solids and total sugar contents was IA, FⅢ, FⅠ and FⅡ. The WUE of DIMFⅠ50FⅡ75FⅢ25 was highest. FIFⅠ25FⅡ75FⅢ50 achieved the highest fruit yield, PFP and contents of soluble solid, vitamin C and carotenoid. DIMFⅠ25FⅡ50FⅢ75 had the highest total sugar content and the lowest titratable acid content. Based on the comprehensive scoring method, DIMFⅠ50FⅡ75FⅢ25 achieved the optimum score in terms of fruit yield and water–fertilizer use efficiency, while FIFⅠ25FⅡ75FⅢ50 was optimum for fruit quality. Further, the TOPSIS method indicated DIMFⅠ50FⅡ75FⅢ25 had the optimal comprehensive benefit. To obtain high yield, quality and water–fertilizer use efficiency, the recommended water and fertilizer scheduling was irrigation with 75% ETc and fertilization with 50, 75 and 25 kg ha−1 at the flowering, fruit expansion and fruit ripening stages, respectively. The research results provided a scientific reference for identified optimum combination irrigation and fertilizer in the xerothermic environment of southwest China.

This paper investigates the seepage-induced erosion by conducting a series of discrete element method simulations on the bimodal soils with gap ratio (G) range from 2 to 6 and fines content (F) range from 15% to 70%. The final erosion ratio (Erf, the ratio of the eroded mass at the end of the erosion to the initial total mass) was found to increase as fines content increases and to sharply increase once fines content reaches a critical value (Fcr). Fcr decreases as the gap ratio increases and increases as the confining pressure increases, which can be determined by a fitted Boltzmann equation. The seepage-induced suffusion occurred when F 4, which agrees well with Kezdi’s criterion. Erf decreases as confining pressure increases in underfilled and filled soils, whereas Erf may increase with confining pressure in overfilled soil. Finally, an analytical model based on dimensional analysis is proposed to predict the final erosion ratio.

We investigated the dynamics and factors influencing the N uptake capacity in two sub-root systems of maize seedlings under partial N stress. Maize seedlings were grown in split-root containers containing nutrient solutions. Two N application conditions prior to partial N stress (full-strength N (4.0 mM): CP; N stress: SP) were considered. Thus, two experiments were conducted: (A) four treatments: CPNc, CPN2, CPN1 and CPN0, in which half of the root system was exposed to 4.0 mM, 2 mM, 1 mM and 0 mM N (CPNc–c, CPN2–2, CPN1–1 and CPN0–0), respectively, and the other half received full-strength N (CPNc–c, CPN2–c, CPN1–c and CPN0–c); (B) four treatments: SPNc, SPN2, SPN1 and SPN0, in which both sub-root systems received 4.0 mM, 2 mM, 1 mM and 0 mM N for 6 days, respectively, after which half of the root system was maintained at original N level (SPNc–c, SPN2–2, SPN1–1 and SPN0–0) and the other half received full-strength N (SPNc–c, SPN2–c, SPN1–c and SPN0–c). At 0.25 days after treatment (DAT), CPN2–c and CPN1–c enhanced N inflow rates (Iroot), whereas CPN0–c decreased it by 27.3% compared with CPNc–c, Iroot in CPN2–c, CPN1–c and CPN0–c was uniformly enhanced at 1 DAT, but were only enhanced in CPN0–c at 5 DAT compared with CPNc–c. In contrast, SPN1–c had a significantly increased Iroot by 10.52% compared with SPNc–c, although other treatments showed a negative effect on Iroot at 0.25 DAT. At 1 and 5 DAT, Iroot in SPN2–c, SPN2–2, SPN1–c, SPN1–1 and SPN0–c were significantly lower than that in SPNc–c. Furthermore, CP significantly enhanced Iroot in non-stressed sub-roots compared with SP. Additionally, CPN2 improved shoot dry mass and N use efficiency even under SPN2. Thus, N uptake capacity in each sub-root zone varied not only depending on the severity and duration of the N stress, but was also related to the N status prior to partial N stress. Moreover, the occurrence and disappearance of the root compensatory effect were delayed with increasing N stress severity. A higher compensatory effect developed following CP, even under CPN0.

The winter wheat-summer maize rotation system is one of the most successful intensification agricultural systems in China, but low and unstable grain yield (GY) and high soil nitrate-N leaching caused by erratic precipitation and inefficient management of irrigation and fertilization have attracted wide attention. A two-year (2018–2020) field experiment was carried out to evaluate the effects of four water and nitrogen management strategies (a conventional irrigation and fertilization (CK) and three drip fertigation treatments (rain-fed: RF, deficit irrigation: DI and full irrigation: FI)) on soil water, soil nitrate-N residual, GY, water productivity (WP), nitrogen use efficiency (NUE) and net income in a winter wheat-summer maize rotation system. The results indicated that water and nitrogen management strategies had significant effects on soil water content in the 0–320 cm soil profile. More than 90 mm soil water in the 0–320 cm soil layer was consumed by winter wheat, and the soil water consumption followed the order of RF > DI > CK > FI. The soil water consumption can be replenished by irrigation and precipitation during the summer maize season, but the soil water in 180–260 cm under RF was significantly lower than that in the other treatments, which could not be fully replenished. There was no significant difference in the nitrate-N residual in the 0–180 cm soil layer among the treatments at harvest, but the nitrate-N residual rate of CK (less than 40% and 30% at winter wheat and summer maize harvest) was significantly lower than that of drip fertigation (more than 50% and 40% at winter wheat and summer maize harvest) in the 0–60 cm soil profile, but significantly higher than that in the 60–180 cm soil profile. These results indicate that drip fertigation had a lower risk of nitrate leaching compared with CK treatment. GY and NUE of DI and FI treatments were significantly higher than those of CK and RF treatments, but DI used 25% less irrigation water than FI, resulting in higher WP. The WP of DI was increased by 6.8–7.4% and 4.2–16.0% for winter wheat and summer maize compared with FI, respectively. From the perspective of winter wheat-summer maize rotation system, the two-year average net income of DI was increased by 2.8%, 37.9% and 59.9% compared with FI, RF and CK, respectively. Therefore, deficit irrigation with nitrogen fertigation was recommended as a sustainable fertigation strategy for achieving higher grain yield, nitrogen use efficiency, water productivity and net income and reducing the risk of soil nitrate-N leaching in the winter wheat-summer maize rotation system.

Drip fertigation is beneficial to improve crop grain yield (GY), water productivity (WP) and nitrogen use efficiency (NUE), but it is not clear whether drip fertigation can improve economic benefit and how much water and nitrogen should be applied for wheat-maize rotation system in semi-humid and drought-prone regions. A two-year (2018–2020) winter wheat-summer maize rotation field experiment (including twelve drip fertigation treatments (complete combination design of three irrigation (RF: rain-fed, DI: deficit irrigation, 75% ETc, and FI: full irrigation, 100% ETc) and four nitrogen levels (N0: no nitrogen, N1: 85 kg ha−1 for wheat and 90 kg ha−1 for maize, N2: 170 kg ha−1 for wheat and 150 kg ha−1 for maize) and N3: 255 kg ha−1 for wheat and 210 kg ha−1 for maize)) and a conventional practice (Con)) was conducted to explore the response of GY, NUE, WP and net income to different water and nitrogen levels in the Guanzhong Plain of China. The results showed that water and nitrogen application levels had significant effects on GY, NUE, WP and net income of winter wheat and summer maize. For winter wheat, DIN2 (the combination of irrigation and nitrogen) achieved the highest GY (9.2 t ha−1, two-year average), WP (2.11 kg m−3) and net income (11 839 CNY ha−1). For summer maize, the highest GY (11.1 t ha−1), WP (2.32 kg m−3) and net income (14 859 CNY ha−1) were observed at DIN3, RFN3 and DIN2, respectively. For winter wheat-summer maize rotation system, the highest GY (20.2 t ha−1, winter wheat + summer maize, two-year average) and net income (26 698 CNY ha−1) were observed at DIN2; and the highest WP of 2.15 kg m−3 was obtained at RFN3, but had insignificant difference with DIN2 (2.13 kg m−3) (P > 0.05). Therefore, deficit irrigation coupled with 320 kg N ha−1 (170 kg ha−1 for wheat, 150 kg ha−1 for maize) was considered as the best drip fertigation strategy for achieving high GY, WP and net income in winter wheat-summer maize rotation system. Moreover, the response surface methodology was used to determine the optimal water consumption and nitrogen application rate based on binary quadratic regression analysis. The results showed that the GY and net income can synchronously achieve 95~100% maximum values when the water consumption ranged from 434 to 496 mm and 458–500 mm, and the nitrogen application rate ranged from 165 to 211 kg ha−1 and 187–250 kg ha−1 for winter wheat and summer maize, respectively.

Understanding the response of spike density (SD), grain number per spike (GN), and thousand kernel weight (TKW) to the application amount of nitrogen and irrigation, and clarifying the contribution of nitrogen and irrigation to the increased yield are vital for achieving high grain yield (GY), water and nitrogen use efficiency (WUE and NUE) in precision agriculture. A two-year (2018–2020) drip fertigated winter wheat experiment was conducted with three irrigation levels (rain-fed (RF), deficit irrigation (DI, 75% ETc) and full irrigation (FI, 100% ETc)) as main plot and four nitrogen levels (0 (NN), 85 (N3), 170 (N2) and 255 (N1) kg N hm−2) as subplot in Northwest China. The results showed that the tillers per plant (TP) significantly increased with increasing nitrogen application amount (0–255 kg hm−2), but the SD had insignificant difference between N1 and N2 levels due to lower effective spike rate (ESR) of N1. The GN firstly increased and then decreased with increasing nitrogen application amount. However, the TKW continued to decrease with increasing nitrogen application amount. Irrigation significantly increased SD and GN, but the impact on TKW showed uncertainty during two growing seasons. The structure equation model showed that both irrigation and nitrogen indirectly affect GY by affecting yield components, and nitrogen had the stronger influence to SD, GN and TKW than irrigation in this study. The highest GY (9.10 and 9.28 t hm−2 in 2018–2019 and 2019–2020, respectively) was observed at DIN2, which increased by 200% and 277% in 2018–2019 and 2019–2020 growing seasons compared with RFNN treatment, respectively. And among these increased yield, more than 65% and approximately 20% were contributed by the application of nitrogen and irrigation, respectively. In addition, DIN2 also obtained the highest WUE and higher NUE due to lower actual evapotranspiration and nitrogen application amount. Therefore, deficit drip irrigation (75%ETc) coupled with 170 kg N hm−2 was the best management strategy of irrigation and nitrogen under drip fertigation in Northwest China.

To understand the functions of Populus euphratica CPD (PeCPD) and DWF4 (PeDWF4), the responses to exogenous phytohormone in Arabidopsis-PeCPD and -PeDWF4 transgenic lines (PeCPD-TL and PeDWF4-TL) and corresponding wild type (WT) seedlings were investigated. Results showed that all of PeCPD-TL, PeDWF4-TL and WT seedlings cultured on the mediums containing 2,4-dichlorophenoxyacetic acid (2,4-D) + 6-benzylaminopurin (6-BA) or 2,4-D + 6-BA + brassinolide (BL) could be dedifferentiated to callus with 100% frequency, but they displayed strong differences in callus formation sites, callus growth rates (CGRs) and tissue dedifferentiation degrees. On the medium containing 2,4-D alone, the seedlings of all the plants could formed callus, but callus formation times (CFTs) were delayed, and callus formation rates (CFRs) were differentially decreased. After adding lower concentrations of BL, their CFRs were all restored to 100%, but tissue dedifferentiation degrees were obviously lower than these on the mediums with 2,4-D + 6-BA or 2,4-D + 6-BA + BL. On the mediums containing 6-BA or 6-BA + BL, the seedlings of all the plants failed to produce callus. Semi-quantitative RT-PCR analysis also showed that the transcription levels of PeCPD, PeDWF4, AtCPD and AtDWF4 in PeCPD-TL, PeDWF4-TL and WT were evidently different. These results suggest that PeCPD and PeDWF4 play similar but not exactly the same roles in the regulation of callus morphogenesis of Arabidopsis seedlings, and that BL can partially replace the role of cytokinin to induce callus formation through interacting with auxin.

In this study, we analyzed the meteorological processes associated with 2018 tropical cyclone No. 14, “Yagi.” TC Yagi continued moving northeastward after losing its numerical designation from the National Meteorological Center of the China Meteorological Administration (CMA) because of weakening and then restrengthened when it moved over the Bohai Sea, inducing an ocean gale on 14-15 August 2018. The results of our investigation revealed that the continued northeastward movement of Yagi on 14 August was related to the divergence of the upper-level westerly jet stream, the northward shift of the subtropical high in the midtroposphere, as well as the steering flow and asymmetrical air flow around the disturbance itself in the lower troposphere. The enhancement of Yagi over the Bohai Sea on the night of 14 August was related to the decrease of friction over the ocean and the increase of diabatic heating from the sea surface flux. The wind speed increased to a maximum when the depression moved over the Bohai Sea, an occurrence that was not only due to the enhancement of the cyclone itself but also due to the flow of cold air from high latitudes along the north side of the Bohai Sea. The behavior of the cold air was related to the shift of the convergence zone in the upper-level westerly jet at 200 hPa, long-wave troughs and ridges at 500 hPa, and terrain effects. Thus, the gale development in the Bohai Sea was due to both the enhancement of tropical cyclone Yagi after it moved over the ocean and the flow of cold air from high latitudes.

A pot experiment was conducted to investigate the effect of potassium (K) fertilization on tomato quality, plant K uptake, water and K use efficiency (WUE and KUE) under deficit irrigation regime. During fruit development stage of the first cluster of fruit, irrigation regimes were comprised of three levels, i.e. 80–90% field capacity (θf) (W1), 70–80% θf (W2) and 60–70% θf (W3); and K fertilization rates were also consisted of three different rates, i.e. 0 g K2O kg−1 soil (K1), 0.46 g K2O kg−1 soil (K2) and 0.92 g K2O kg−1 soil (K3). The result showed that deficit irrigation as well as increased K fertilization significantly improved quality of fruit where, soluble sugar, titratable acid and content of vitamin C were positively correlated to K concentration of leaf ([K]leaf), indicating that [K]leaf may have a role to improve fruit quality. The highest plant WUE was observed in W1 plants, which consumed the most water and produced the highest dry mass. K fertilization had no effect on WUE based on biomass, but had positive effect on K concentration and K accumulation in each tissue, hereby increased total K uptake, while decreased KUE.

Reducing soil nitrate leaching losses from agricultural ecosystem and improving crop yield and nitrogen use efficiency with effective nitrogen management strategies are extremely important for sustainable agricultural development. A-two-year field experiment was conducted to investigate the effects of five nitrogen management strategies (CK: no nitrogen application; FP: applying 210 kg N ha−1 at sowing; MFP: applying 105 kg N ha−1 at sowing and top-dressing 105 kg N ha−1 at V12 stage; Drip210 and Drip150: multi-split-N fertigation (MSF, sowing: 20%, V6: 30%, V14: 30% and R1: 20%) with 210 and 150 kg N ha−1) on soil nitrate-N (NO3−-N) distribution and residual, nitrate leaching losses, nitrogen use efficiency (NUE), grain yield and economic benefit of summer maize in Northwest China. The results showed that MSF produced more consistent soil NO3−-N content over the entire maize growing season. The two-year average leachate NO3−-N concentration of Drip210 and Drip150 was 24.1 and 19.2 mg L−1, significantly lower than FP and MFP. The total nitrate leaching losses (TNLL) of Drip210 and Drip150 were significantly lower than that of FP and MFP (P

Internal erosion can trigger severe engineering disasters, such as the failure of embankment dams and uneven settlement of buildings and sinkholes. This paper comprehensively reviewed the mechanisms of soil internal erosion studied by numerical simulation, which can facilitate uncovering the internal erosion mechanism by tracing the movement of particles. The initiation and development of internal erosion are jointly influenced by the geometric, mechanical, and hydraulic conditions, which determine the pore channels and force chains in soil. The geometric conditions are fundamental to erosion resistance, whereas the mechanical conditions can significantly change the soil erosion resistance, and the hydraulic conditions determine whether erosion occurs. The erosion process can be divided into particle detachment, transport, and clogging. The first is primarily affected by force chains, whereas the latter two are mostly affected by the pore channels. The stability of the soil is mainly determined by force chains and pore channels, whereas the hydraulic conditions act as external disturbances. The erosion process is accompanied by contact failure, force chain bending, kinetic energy burst of particles, and other processes due to multi-factor coupling.

Rapid estimation of crop nitrogen (N) status is helpful for achieving precise N fertilizer management, so as to promote the collaborative improvement of yield, quality and N use efficiency. To establish a method for rapidly estimating N status of apple-trees based on hyperspectral remote sensing, a field experiment on apple trees with four levels of N application were conducted in Luochuan, Yan'an, China in 2018 and 2019. Hyperspectral data at apple tree canopy scale were obtained at different phenological stages. The outliers in the dataset were detected by Monte-Carlo cross-validation (MCCV). A total of 15 forms of spectral data were analyzed, including the raw spectrum (RS), Savitzky-Golay (SG) smoothing, normalization by the mean (NME), standard normal transformation (SNV), multiplicative scatter correction (MSC) and their combination with the first-order derivative (FD) or second-order derivative (SD). The results showed that SNV-FD was the best preprocessing method for apple tree canopy spectral data on the Loess Plateau. For SNV-FD data, competitive adaptive reweighted sampling (CARS), successive projection algorithm (SPA), random frog (Rfrog), and partial least squares (PLS) were used to extract feature variables. The feature wavelengths extracted by CARS, SPA and Rfrog were widely distributed in visible and near-infrared (VIS/NIR) range. The feature variables extracted by PLS were fewer, but had a strong interpretation. Based on these feature variables, linear and nonlinear models including partial least squares regression (PLSR), support vector machine (SVM), back-propagation artificial neural network (BPANN), extreme learning machine (ELM) and random forest (RF), were used to establish the prediction model. Among all the models, four nonlinear modeling methods were superior to the linear method. The model by Rfrog-ELM achieved the best results (R2P = 0.843, RMSEP = 2.461 g·kg−1, RPD = 2.508). This study demonstrated that the combination of SNV-FD, Rfrog and ELM was feasible and reliable for estimating the leaf N content in apple-trees on the Loess Plateau, China.

In this paper, hierarchical porous activated carbon@manganese dioxide (AC@MnO 2 ) core-shell nanocomposite for supercapacitors have been synthesized by a facile in - situ chemical redox reaction. The microstructures of as-prepared materials have been characterized by Fourier transform-infrared spectroscopy (FT-IR), X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen sorption isotherm measurements. Electrochemical properties of as-prepared samples were studied by cyclic voltammetry (CV), galvanostatic charging–discharging (GCD) and electrochemical impedance spectroscopy (EIS) tests in 6 mol L −1 KOH aqueous electrolytes based on their two-electrode symmetric capacitors. Thanks to the advanced hierarchical porous core/shell nanostructures, the AC@MnO 2 composite exhibit a larger specific surface area (658.1 m 2 g −1 ) compared with either AC (557.9 m 2 g −1 ) or MnO 2 (113.6 m 2 g −1 ) and show a lower charge transfer resistance (0.74 Ω) and Warburg resistance (0.16 S sec 0.5 ) than those of AC (0.96 Ω, 0.11 S sec 0.5 ) and MnO 2 (0.82 Ω, 0.054 S sec 0.5 ), which all contribute to the improved electron/ion transport processes and the superior capacitive performance. The results show that AC@MnO 2 composite exhibit enhanced specific capacitance (193 F g −1 , 0.2 A g −1 ), rate performance (154 F g −1 , 2 A g −1 ) and cycling stability (77.8% retention after 1500 cycles at 0.8 A g −1 ) than those of AC (181 F g −1 , 0.2 A g −1 ; 129 F g −1 , 2 A g −1 ; 50% retention after 1500 cycles) and MnO 2 (64 F g −1 , 0.2 A g −1 ; 10 F g −1 , 2 A g −1 ; 11.3% retention after 1500 cycles). The superior capacitive behavior and the facile preparation method indicate a good candidate of the hierarchical porous AC@MnO 2 core/shell nanocomposite for supercapacitors.

Facing with the scarcity of water resource and irrational fertilizer use, it is highly important to supply plants with water and fertilizer in a coordination pattern to improve yield with high water use efficiency (WUE). A field experiment was conducted in 2012 and 2014 to investigate the effect of N supply methods on biomass accumulation and distribution, yield components and WUE of maize (Zea mays L.) under different partial root-zone irrigations in the Hexi corridor of Northwest China. Three irrigation methods included alternate furrow irrigation (AI), fixed furrow irrigation (FI) and conventional furrow irrigation (CI). Three N supply methods included alternate N supply (AN), fixed N supply (FN) and conventional N supply (CN), were applied in combination with each irrigation method. Leaf area index (LAI), shoot biomass and root length density at different growth stages, yield components, biomass distribution in different shoot organs and WUE of maize were determined. Results showed that, LAI at the R1, R2 and R4 stages, shoot biomass at the R6 stage, grain yield, harvest index (HI) and WUE of maize were significantly increased by AN or CN compared to FN in each irrigation method as well as by AI compared to CI and FI in each N supply method. Compared to CI coupled with CN (CICN), AI coupled with AN or CN (AIAN or AICN) significantly increased the LAI, shoot biomass, grain yield and WUE of maize. The biomass distribution proportion in kernel and contribution rate of the biomass transfer from other shoot organ to grain were also increased by AIAN and AICN, resulting in significantly higher HI. These increased shoot biomass accumulation and WUE were related to the enhanced LAI and root growth. AIAN and AICN also achieved a greater kernels number per cob and 1000-kernel weight compared to CICN. Thus, AI coupled with CN or AN are proposed as a better pattern of irrigation and nitrogen application with positive regulative effects on shoot biomass accumulation and distribution and WUE in the Hexi Corridor area of Northwest China and other regions with similar environments. These results can also provide a basis for in-depth understanding of the mechanism of biomass accumulation and growth responses to nitrogen supply methods.

Dynamic malicious jamming of spectrum throughout the entire communication band is a major issue confronted by tactical communications. The conventional spectrum access scheme based on the central control node fails to satisfy the demand of tactical communications; it has a number of drawbacks including low battlefield survival rates, high computational complexity, large interactive communication overhead and slow reaction to dynamic jamming. In this paper, we propose a distributed multi-agent spectrum access strategy without the interactive communication overhead to evade dynamic jamming. Furthermore, A simplified Q reinforcement learning algorithm is applied to alleviate collisions of spectrum among nodes. Under the proposed strategy, all nodes can predict and evade dynamic jamming as well as avoid collisions of spectrum usage with other nodes. Simulation results verify the collision-avoidance learning algorithm and indicate that the proposed strategy outperforms the random spectrum access strategy.

In this paper, we investigate a cognitive radio network (CRN) for a multiple-input multiple-output multiple-eavesdropper (MIMOME) secrecy channel with artificial noise. The cognitive transmitter aims to send confidential messages to its receiver in the presence of multiple eavesdroppers. While the artificial noise (AN) approach or masked precoding is applied to provide the information secrecy, the target of this paper is to maximize the achievable secrecy rate with the constraint of the total transmit power, as well as the interference temperature limits (ITL) for the primary user. The original optimization problems are non-convex and challenging, which is efficiently solved via a two-layer decomposition approach. The inner layer problem can be efficiently handled by solving a sequence of semi-definite problems, and the outer layer problem can be recast as a single-variable optimization problem, which is tackled by one-dimensional search. We also generalize the framework to an imperfect CSI case where a worst-case robust secrecy rate max-imization (SRM) formulation is considered. Finally, simulation results are provided to validate the secrecy performance of the proposed methods.

Faced with the scarcity of water resource and irrational fertilizer use, it is highly important to supply plants with water and fertilizer at desiderated stages to improve yield with high water use efficiency (WUE). A pot experiment was conducted to investigate the effects of growth stage-specific water deficiency and potassium (K) fertilization on tomato yield and WUE. The entire growing season of tomato was divided into 5 stages: vegetative growth stage (VG), flowering and fruit setting stage (FS), early fruit growth stage (FG), fruit development stage (FD) and fruit maturity stage (FM). Three soil moisture (W) and three K fertilization levels were set up. W levels included W1, W2 and W3, indicating that soil water was maintained at 60-70% field capacity, 70-80% field capacity, and 80-90% field capacity, respectively. K levels included K1, K2 and K3, indicating that 0 g K2O per kg soil, 0.46 g K2O per kg soil and 0.92 g K2O per kg soil was applied. All combinations of the three W and three K levels were solely imposed at each of the five growth stages, for other four stages, plants were watered to 80-90% field capacity without K fertilizer (W3K1). The permanent W3K1 over the entire growth stage was taken as control (CK). The results showed that W deficiency imposed at all stages significantly affected tomato yield (P

Effects of severity and duration of osmotic stress on partial root system were investigated on root hydraulic conductance (L p ) and growth in each sub-root system. The maize seedlings were raised in nutrient solution with the roots divided equally into two containers. At 12 days after transplanting, half of root system was subjected to osmotic stress of −0.2, −0.4 and −0.6 MPa using PEG 6000 added in the solution, and no PEG 6000 solution was taken as control (CK). L p and root growth in each sub-root system were measured at 0, 0.25, 0.5, 1, 3, 5, 7 and 9 days after treatment (DAT). Results show that compared to CK, −0.2 MPa treatment enhanced the hydraulic conductance per root area (L pr ) in non-stressed sub-root system by 12 % at 0.5 DAT. In −0.4 MPa treatment, L pr in non-stressed sub-root system was significantly increased at 9 DAT. But in −0.6 MPa treatment, significant decrease of 12–40 % was observed in non-stressed sub-root system during 0.5–3 DAT if compared to CK, indicating that the threshold of osmotic stress for the compensatory effect of water uptake in non-stressed sub-root system was between −0.2 and −0.4 MPa. In addition, the root area growth rate in non-stressed sub-root system was significantly higher than that in CK during 0.25–0.5, 1–3 and 5–7 DAT for −0.2, −0.4 and −0.6 MPa treatments, respectively. Similar trend also was observed for root length growth rate, indicating that osmotic stress could still stimulate the compensatory effect of root growth other than water uptake under partial root system. Moreover, the occurrence of such compensatory effect delayed with the increasing osmotic stress. Meanwhile, −0.2 MPa treatment had no significant effect on maize shoot growth but −0.4 and −0.6 MPa treatments inhibited shoot biomass accumulation, which resulted in higher root/shoot ratio in −0.4 and −0.6 MPa treatments. Thus root plasticity in hydraulic conductance and root growth in different root zones varied largely depending on the severity and duration of osmotic stress under partial root system.