Effects of tillage and cropping sequences on crop production and environmental benefits in the North China Plain.

The ever-increasing trend of greenhouse gas (GHG) emissions is accelerating global warming and threatening food security. Environmental benefits and sustainable food production must be pursued locally and globally. Thus, a field experiment was conducted in 2015 to understand how to balance the trade-offs between agronomic productivity and environment quality in the North China Plain (NCP). Eight treatments consisted of two factors, i.e., (1) tillage practices: rotary tillage (RT) and no-till (NT), and (2) cropping sequences (CS): maize-wheat-soybean-wheat (MWSW), soybean-wheat-maize-wheat (SWMW), soybean-wheat (SW), and maize-wheat (MW). The economic and environmental benefits were evaluated by multiple indicators including the carbon footprint (CF), maize equivalent economic yield (MEEY), energy yield (EY), and carbon sustainability index (CSI). Compared with NT, RT increased the EY and MEEY, but emitted 9.4% higher GHGs. Among different CSs, no significant reduction was observed in CF. The lowest (2.0 Mg CO2-eq ha-1 year-1) and the highest (5.6 Mg CO2-eq ha-1 year-1) CF values were observed under MW and SWMW, respectively. However, CSs with soybean enhanced MEEY and the net revenue due to their higher price compared to that of MW. Although the highest CSI was observed under RT-MW, soybean-based crop rotation could offset the decline in CSI under NT when compared to that for RT. These findings suggest that conservation agriculture (CA) could enhance the balance in trade-offs between economic and environmental benefits. Additional research is needed on how to achieve high crop production by establishing a highly efficient CA system in the NCP.

Improving soil aggregates stability and soil organic carbon sequestration by no-till and legume-based crop rotations in the North China Plain.

Conservation agriculture (CA) has been adopted worldwide on about 200 Mha to enhance soil organic carbon (SOC) for mitigating climate change. However, as a crucial mechanism to sequester SOC, how the protection of aggregates responds to the interaction between no-till and crop rotations (two principles of CA) remains unknown. Thus, a field experiment with six treatments [e.g., no-till or rotary tillage under the maize-wheat-soybean-wheat system (NT-MWSW, RT-MWSW), no-till or rotary tillage under the maize-wheat system (NT-MW, RT-MW), and no-till or rotary tillage under the soybean-wheat system (NT-SW, RT-SW)] was conducted from June 2018 to June 2021 in the North China Plain (NCP) to assess their effects on aggregation and SOC. Results indicated that macroaggregates (> 0.25 mm) were the main contributors to the soil carbon (C) pool, comprised 64.7-87.3 % of aggregates, and encompassed 64.9-73.1 % of the SOC stock. NT increased not only the proportion of macroaggregates but also aggregate stability (i.e., mean weight diameter and geometric mean diameter). Significant positive effects from legumes were observed under NT. SW increased by 13.6 % macroaggregate-associated SOC under NT in 0-20 cm compared to that under MW. Additionally, the conversion rate of straw C input under NT-SW was higher than that in other treatments, augmenting it by 9.4-21.9 %. This may be attributed to the higher macroaggregate total nitrogen (increased by 1.7-15.9 %) in 0-10 cm under legume-based crop rotations compared to that under MW, resulting in lower C: N ratios, which promoted the decomposition of straw. Furthermore, the total potential mineralization of macroaggregates under NT legume-based crop rotations was 3.0-16.0 % higher than that of MW. Thus, a legume-based NT system can significantly improve soil macro-aggregation, increase the conversion rate of straw C input, and reduce C loss, which can be a viable practice to enhance SOC sequestration capacity under CA in the NCP.

Sieving soil before incubation experiments overestimates carbon mineralization but underestimates temperature sensitivity.

The sensitivity of soil organic carbon (SOC) mineralization to temperature could affect the future atmospheric CO2 levels under global warming. Sieved soils are widely used to assess SOC mineralization and its temperature sensitivity (Q10) via laboratory incubation. However, sieved soils cause a temporary increase in mineralization due to the destruction of soil structure, which can affect estimates of SOC mineralization, especially in soils managed with no-till (NT). To identify the effects of soil sieving on SOC mineralization and Q10, soil was collected from an 11-year field experiment under a wheat-maize cropping system managed with a combination of tillage [NT and plow tillage (PT)] and residue [residue returning (RR) and residue removal (R0)]. Soil was either sieved or left in an undisturbed state and incubated at 15 °C and 25 °C. SOC mineralization in sieved soils at 25 °C was 47.28 g C kg-1 SOC, 160.1% higher than SOC mineralization in undisturbed soils (P < 0.05). Interestingly, Q10 values in sieved soils were 1.29, 77.6% lower than Q10 in undisturbed soils (P < 0.05). Highly significant correlations (P < 0.01) were observed between sieved and undisturbed soils for SOC mineralization (r = 0.85-0.98) and Q10 (r = 0.78-0.87). Soil macro-aggregates had lower SOC mineralization by 6.1-21.9%, but higher Q10 values by 4.7-6.5% compared with micro-aggregates, contributing to lower mineralization and higher Q10 under NT and RR. Furthermore, structure equation and random forest modelling showed that increased SOC contents in NT and RR could not only reduce SOC mineralization, but also constrained the improvement of Q10 in NT and RR. Overall, these results indicated that although sieved soils overestimated SOC mineralization and underestimated Q10 due to the destruction of macro-aggregates, the patterns between treatments were similar and sieving soil for incubation is considered as a suitable approach to evaluate the relative impacts of NT and RR on SOC mineralization and Q10.

Responses of soil pH to no-till and the factors affecting it: A global meta-analysis.

No-till (NT) is a sustainable option because of its benefits in controlling erosion, saving labor, and mitigating climate change. However, a comprehensive assessment of soil pH response to NT is still lacking. Thus, a global meta-analysis was conducted to determine the effects of NT on soil pH and to identify the influential factors and possible consequences based on the analysis of 114 publications. When comparing tillage practices, the results indicated an overall significant decrease by 1.33 ± 0.28% in soil pH under NT than that under conventional tillage (p < .05). Soil texture, NT duration, mean annual temperature (MAT), and initial soil pH are the critical factors affecting soil pH under NT. Specifically, with significant variations among subgroups, when compared to conventional tillage, the soil under NT had lower relative changes in soil pH observed on clay loam soil (-2.44%), long-term implementation (-2.11% for more than 15 years), medium MAT (-1.87% in the range of 8-16℃), neutral soil pH (-2.28% for 6.5 < initial soil pH < 7.5), mean annual precipitation (-1.95% in the range of 600-1200 mm), in topsoil layers (-2.03% for 0-20 cm), with crop rotation (-1.98%), N fertilizer input (the same for NT and conventional tillage) of 100-200 kg N ha-1 (-1.83%), or crop residue retention (-1.52%). Changes in organic matter decomposition under undisturbed soil and with crop residue retention might lead to a higher concentration of H+ and lower of basic cations (i.e., calcium, magnesium, and potassium), which decrease the soil pH, and consequently, impact nutrient dynamics (i.e., soil phosphorus) in the surface layer under NT. Furthermore, soil acidification may be aggravated by NT within site-specific conditions and improper fertilizer and crop residue management and consequently leading to adverse effects on soil nutrient availability. Thus, there is a need to identify strategies to ameliorate soil acidification under NT to minimize the adverse consequences.

Mechanisms of soil organic carbon stability and its response to no-till: A global synthesis and perspective.

Mechanisms of soil organic carbon (SOC) stabilization have been widely studied due to their relevance in the global carbon cycle. No-till (NT) has been frequently adopted to sequester SOC; however, limited information is available regarding whether sequestered SOC will be stabilized for long term. Thus, we reviewed the mechanisms affecting SOC stability in NT systems, including the priming effects (PE), molecular structure of SOC, aggregate protection, association with soil minerals, microbial properties, and environmental effects. Although a more steady-state molecular structure of SOC is observed in NT compared with conventional tillage (CT), SOC stability may depend more on physical and chemical protection. On average, NT improves macro-aggregation by 32.7%, and lowers SOC mineralization in macro-aggregates compared with CT. Chemical protection is also important due to the direct adsorption of organic molecules and the enhancement of aggregation by soil minerals. Higher microbial activity in NT could also produce binding agents to promote aggregation and the formation of metal-oxidant organic complexes. Thus, microbial residues could be stabilized in soils over the long term through their attachment to mineral surfaces and entrapment of aggregates under NT. On average, NT reduces SOC mineralization by 18.8% and PE intensities after fresh carbon inputs by 21.0% compared with CT (p < .05). Although higher temperature sensitivity (Q10 ) is observed in NT due to greater Q10 in macro-aggregates, an increase of soil moisture regime in NT could potentially constrain the improvement of Q10 . This review improves process-based understanding of the physical and chemical mechanism of protection that can act, independently or interactively, to enhance SOC preservation. It is concluded that SOC sequestered in NT systems is likely to be stabilized over the long term.

Germline Variants and Genetic Interactions of Several EMT Regulatory Genes Increase the Risk of HBV-Related Hepatocellular Carcinoma.

Epithelial-mesenchymal transition (EMT) plays an important role in the development of hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC). We hypothesized that germline variants in the major EMT regulatory genes (SNAIL1, ZEB1, ZEB2, TWIST1) may influence the development of HBV-related HCC. We included 421 cases of HBsAg-positive patients with HCC, 1371 cases of HBsAg-positive subjects without HCC [patients with chronic hepatitis B (CHB) or liver cirrhosis (LC)] and 618 cases of healthy controls in the case-control study. Genotype, allele, and haplotype associations in the major EMT regulatory genes were tested. Environment-gene and gene-gene interactions were analysed using the non-parametric model-free multifactor dimensionality reduction (MDR) method. The SNAIL1rs4647958T>C was associated with a significantly increased risk of both HCC (CT+CC vs. TT: OR=1.559; 95% confidence interval [CI], 1.073-2.264; P=0.020) and CHB+LC (CT+CC vs. TT: OR=1.509; 95% CI, 1.145-1.988; P=0.003). Carriers of the TWIST1rs2285681G>C (genotypes CT+CC) had an increased risk of HCC (CG+CC vs. GG: OR=1.407; 95% CI, 1.065-1.858; P=0.016). The ZEB2rs3806475T>C was associated with significantly increased risk of both HCC (P recessive =0.001) and CHB+LC (P recessive<0.001). The CG haplotype of the rs4647958/rs1543442 haplotype block was associated with significant differences between healthy subjects and HCC patients (P=0.0347). Meanwhile, the CT haplotype of the rs2285681/rs2285682 haplotype block was associated with significant differences between CHB+LC and HCC patients (P=0.0123). In MDR analysis, the combination of TWIST1rs2285681, ZEB2rs3806475, SNAIL1rs4647958 exhibited the most significant association with CHB+LC and Health control in the three-locus model. Our results suggest significant single-gene associations and environment-gene/gene-gene interactions of EMT-related genes with HBV-related HCC.

Calcitonin gene-related peptide inhibits angiotensin II-induced NADPH oxidase-dependent ROS via the Src/STAT3 signalling pathway.

We had previously demonstrated that the calcitonin gene-related peptide (CGRP) suppresses the oxidative stress and vascular smooth muscle cell (VSMC) proliferation induced by vascular injury. A recent study also indicated that CGRP protects against the onset and development of angiotensin II (Ang II)-induced hypertension, vascular hypertrophy and oxidative stress. However, the mechanism behind the effects of CGRP on Ang II-induced oxidative stress is unclear. CGRP significantly suppressed the level of reactive oxygen species (ROS) generated by NADPH oxidase in Ang II-induced VSMCs. The Ang II-stimulated activation of both Src and the downstream transcription factor, STAT3, was abrogated by CGRP. However, the antioxidative effect of CGRP was lost following the expression of constitutively activated Src or STAT3. Pre-treatment with H-89 or CGRP8-37 also blocked the CGRP inhibitory effects against Ang II-induced oxidative stress. Additionally, both in vitro and in vivo analyses show that CGRP treatment inhibited Ang II-induced VSMC proliferation and hypertrophy, accompanied by a reduction in ROS generation. Collectively, these results demonstrate that CGRP exhibits its antioxidative effect by blocking the Src/STAT3 signalling pathway that is associated with Ang II-induced VSMC hypertrophy and hyperplasia.

Calcitonin gene-related peptide attenuates angiotensin II-induced ROS-dependent apoptosis in vascular smooth muscle cells by inhibiting the CaMKII/CREB signalling pathway.

Apoptosis is associated with various cardiovascular diseases. CGRP exerts a variety of effects within the cardiovascular system, and protects against the onset and development of angiotensin (Ang) II-induced vascular dysfunction and remodelling. However, it is not known whether CGRP has a direct effect on Ang II-induced apoptosis in vascular smooth muscle cells (VSMCs), and the mechanism underlying the anti-apoptotic role remains unclear. In this study, CGRP significantly suppressed reactive oxygen species (ROS) and apoptosis in Ang II-induced VSMCs. In VSMCs pre-treated with a CGRP receptor antagonist (CGRP8-37), the CGRP-mediated inhibition of Ang II-induced ROS and apoptosis was completely abolished. Moreover, pre-treatment with N-acetyl-L cysteine (NAC), an ROS scavenger, blocked the effects of CGRP on Ang II-induced apoptosis. In addition, the activation of CaMKII and the downstream transcription factor CREB stimulated by Ang II was abrogated by CGRP. Importantly, in both CGRP and NAC-treated VSMCs, CGRP failed to further attenuate CaMKII and CREB activation. The results demonstrate that CGRP attenuated Ang II-induced ROS-dependent apoptosis in VSMCs by inhibiting the CaMKII/CREB signalling pathway.

An Azure ACES Early Warning System for Air Quality Index Deteriorating.

With the development of industrialization and urbanization, air pollution in many countries has become more serious and has affected people's health. The air quality has been continuously concerned by environmental managers and the public. Therefore, accurate air quality deterioration warning system can avoid health hazards. In this study, an air quality index (AQI) warning system based on Azure cloud computing platform is proposed. The prediction model is based on DFR (Decision Forest Regression), NNR (Neural Network Regression), and LR (Linear Regression) machine learning algorithms. The best algorithm was selected to calculate the 6 pollutants required for the AQI calculation of the air quality monitoring in real time. The experimental results show that the LR algorithm has the best performance, and the method of this study has a good prediction on the AQI index warning for the next one to three hours. Based on the ACES system proposed, it is hoped that it can prevent personal health hazards and help to reduce medical costs in public.

Prostaglandin E2 restrains human Treg cell differentiation via E prostanoid receptor 2-protein kinase A signaling.

Regulatory T cells (Treg cells) belong to a class of immunosuppressive cells that control the pathological changes of autoimmunity and inflammation. Prostaglandin E2 (PGE2) is a potent lipid mediator of immune inflammation including rheumatoid arthritis (RA) that exerts its effects via four subtypes of G-protein-coupled receptors (EP1-4). The ability of PGE2 to regulate human Treg differentiation has not yet been reported. In the current study, we investigated the effects of PGE2 on the differentiation of naïve T cells from healthy and RA patients into Treg cells and the intracellular signaling involved in this process in vitro. Our data indicate that PGE2 negatively influenced the percentage of Treg cells and Foxp3 mRNA expression. The regulatory effects of PGE2 were associated with increased intracellular cAMP levels and PKA activity. EP2 receptors may mediate the inhibitory role of PGE2, since PGE2 actions were mimicked by EP2 agonist (Butaprost) and cAMP agonist (Sp-8-CPT-cAMPS) but were reversed by an EP2 antagonist (PF-04418948) and a PKA inhibitor (H-89). PGE2 negatively modulated the expression of cytotoxic T lymphocyte antigen-4 (CTLA-4) and glucocorticoid-induced tumor necrosis factor receptor-related protein (GITR), as well as the production of interleukin (IL)-10 by Treg cells via EP2 receptors and cAMP/PKA signaling. All these findings indicate that PGE2 can inhibit Treg differentiation mediated through the EP2-cAMP/PKA signaling pathway, and suggest novel immune-based therapies for use in RA treatment.

Association of the NAD(P)H oxidase p22 phox gene C242T polymorphism with type 2 diabetes mellitus, diabetic nephropathy, and carotid atherosclerosis with type 2 diabetes mellitus: A meta-analysis.

BACKGROUND: Several epidemiological studies have evaluated the association between the NAD(P)H oxidase p22 phox gene C242T polymorphism and the risk of type 2 diabetes mellitus (T2DM), diabetic nephropathy (DN), and carotid atherosclerosis with T2DM (CA), but the results are inconclusive. This meta-analysis was therefore designed to clarify these controversies. METHODS: Systematic searches were performed using electronic databases such as MEDLINE, PubMed, EMBASE, and China National Knowledge Infrastructure, as well as through manual searching of the references of identified articles. A total of 11 publications were eligible for this meta-analysis after running a search on the NAD(P)H oxidase p22 phox gene C242T polymorphism, including 7 with outcomes for T2DM, 7 with outcomes for DN, and 3 with outcomes for CA. The pooled odds ratio (OR) with a 95% confidence interval (CI) was calculated using a fixed effects model (FEM) or a random effects model (REM). Publication bias was tested by Begg's funnel plot analysis. Sensitivity analysis was also performed. RESULTS: The results showed a significant association between the NAD(P)H oxidase p22 phox gene C242T polymorphism and T2DM risk in the allelic model (REM: OR = 1.23, 95% CI = 1.06-1.43), additive model (FEM: OR = 1.61, 95% CI = 1.14-2.26), and recessive model (FEM: OR = 1.50, 95% CI = 1.10-2.05). A significant association was also observed for DN in the allelic model (REM: OR = 1.25, 95% CI = 1.06-1.47), additive model (FEM: OR = 1.61, 95% CI = 1.08-2.38), and dominant model (REM: OR = 1.26, 95% CI = 1.03-1.54). However, no association was observed for CA. Similar results were obtained in subgroup analysis based on ethnicity. CONCLUSIONS: Results of this meta-analysis suggest that the NAD(P)H oxidase p22 phox gene 242T allele might be associated with an increased risk of T2DM and DN, but not CA.

[Cut-off points of fasting fingertip capillary blood glucose for detecting both undiagnosed diabetes and pre-diabetes].

OBJECTIVE: To determine the efficient cut-off points of fasting fingertip blood glucose test for undiagnosed diabetes mellitus (DM), impaired glucose tolerance (IGT), and impaired fasting glucose (IFG) in community-based residents aged above 45 years old. METHODS: A cluster-randomized study was conducted from May 2008 to January 2009. A total of 3250 subjects aged above 45 years in two communities of Baoding city received questionnaire investigation and tested for fingertip blood glucose. Those subjects whose capillary blood glucose level ≥ 5.1 mmol/L were subjected to 75 g oral glucose tolerance test. Undiagnosed diabetes mellitus and pre-diabetes were identified by fasting plasma glucose and OGTT. In this study, the cut-off points of fasting capillary blood glucose for detecting undiagnosed diabetes and pre-diabetes were evaluated, using receiver operator characteristic curve (ROC). RESULTS: Of 1351 subjects that having had oral glucose tolerance test, 230 cases were diagnosed as diabetes mellitus (7.3%), 166 cases (5.2%) as IFG, and 204 (6.7%) as IGT under fasting capillary blood glucose as test variable and state variables according to the following criteria. (1) FPG≥7.0 mmol/L or/and 2hPG≥11.1 mmol/L (2) FPG<5.6 mmol/L (3) FPG<7.0 mmol/L and 7.8 mmol/L≤2hPG≤11.1 mmol/L, areas under three ROC curves were 0.905, 0.633 and 0.719, respectively. The cut-off values of screening for undiagnosed DM, IGT and IFG were 6.0 mmol/L, 5.7 mmol/L, and 5.7 mmol/L, respectively. When cut-off value of screening for undiagnosed DM was 6.0 mmol/L, the maximal sensitivity was 78.0% and specificity was 89.3%. But there were both lower sensitivity and specificity in screening for IFG and IGT according to the best predicting value (5.7 mmol/L) from the ROC curves (50.3% and 28.0% vs. 60.8% and 28.0%). CONCLUSION: Fasting capillary blood glucose with the lower cut-point of 6.0 mmol/L in screening for undiagnosed diabetes mellitus alone, was relatively reliable, whereas for both IFG and IGT the fasting fingertip blood glucose tests were fallible. It was convenient and could be used in screening the DM at the community level.

[A case-control study on risk factors of type 2 diabetes mellitus related chronic complications in Baoding city].

OBJECTIVE: To recognize the main risk factors and to provide evidence for prevention and intervention of type 2 diabetes chronic complications. METHODS: A hospital-based frequency matched case-control study including 200 type 2 diabetes mellitus (T2DM) chronic complications cases and 200 controls without T2DM chronic complications was carried out in Baoding city. Relationships between factors and T2DM chronic complications were analyzed by non-conditional uni-variate and multivariate logistic regression methodologies. RESULTS: High C-reactive protein (CRP) (OR = 5.568), dyslipidemia (OR = 4.400), high blood urea nitrogen (BUN) (OR = 4.399), high low density lipoprotein-cholesterol (LDL-C) (OR = 3.594), time of hospitalization (OR = 2.612), grease food intake before developing DM (OR = 2.300), high HbA1c% (OR = 1.747), lack of exercise after the development of DM (OR = 1.672), duration of DM (OR = 1.509), mental stress (OR = 1.427), high-quality sleep (OR = 0.606), well control of blood glucose (OR = 0.517), well control of blood fat (OR = 0.299), insulin injections (OR = 0.155) etc. were all significantly associated with T2DM chronic complications. CONCLUSION: The main risk factors of T2DM chronic complications seemed to be related to high CRP, dyslipidemia, high BUN and high LDL-C. The main protective factors were insulin injections, well control of blood fat and blood glucose, good-quality of sleep, while the unique risk factors of cardiovascular disease seemed to be high LDL-C and mental stress. The unique risk factors of neuropathy were lack of exercise after developing DM and the amount of sweet food intake. The duration of DM appeared to be the common risk factor and the common protective factor on those three complications was insulin injection.

[Genetic analysis and mapping of the rice leafy-hull mutant Oslh].

Oslh (lh=leafy hull), in the japonica cultivar 9522 background, a mutant of Oryza sativa L. spp. japonica cv. 9522 identified from an M(2) population, was mutagenized by irradiation with (60)Co gamma-ray. The Oslh mutant plants flowered about 15 days later than the wild-type plants (Fig.1e). The paleas, lemmas and lodicules of the flowers of Oslh mutant were transformed into leaf-like structures (Fig.1b, d). Genetic analysis of the F(2) progeny from a cross between the Oslh mutant and wild-type japonica cv. 9522 revealed that the Oslh mutant arouse from a single recessive nuclear gene mutation of the cv. 9522. To map the Oslh locus, an F(2) population generated by crossing between Oslh (japonica) mutant and Guangluai4 (indica) was analyzed. The Oslh locus was mapped to the long arm of rice chromosome 3, between a SSR marker RM5475 and an InDel marker GY305, 2.9 and 1.5 cM away from these two markers respectively (Fig.4). These results are useful for further cloning and functional analysis of the OsLH gene.

[Development of Triticum aestivum-Leymus racemosus translocation lines NAU601 and NAU618 and their test-cross analysis with double ditelosomic].

Two Triticum aestivum-Leymus racemosus disomic translocation lines were selected and identified from irradiated progenies of T. aestivum-L. racemosus addition lines Lr. 2 and Lr. 7 by somotic chromosome C-banding and fluorescence in situ hybridization by using L. racemosus genomic DNA as probe. NAU618 (MS142-3), 2n = 44, is a disomic addition translocation line with a pair of translocated chromosome consisting of 5/6 length of L. racemosus chromosome Lr. 7 (including centromere) and 1/3 distal part of wheat chromosome 1A short arm. The alien segment is about 4/5 of the length of translocated chromosome. NAU601 (MS101-4), 2n = 42, is a disomic translocation lines with a pair of translocated chromosome consisting of 4B short arm, interstitial 1/3 part of 4BL and almost Lr. 2S, the alien segment is a half of the long arm of translocated chromosome. The results of test-cross analysis with T. aestivum c. v Chinese Spring double ditelosomic combine meiotic chromosomes C-banding indicated that the translocated chromosomes in these two translocation lines were involved in chromosome 1A and 4B respectively. Their resistance to wheat scab was identified using single floret inoculation in three successive years and showed that the resistance of NAU618(MS142-3) was similar to that of resistant check variety Sumai 3, and NAU601(MS101-4) was lower than Sumai 3 but much higher than susceptible parent Chinese Spring.