[Effect of No-tillage on Soil Aggregates in Farmland：A Meta Analysis].

In order to clarify the impact of no-tillage on the quality of farmland soil aggregates in China and promote the adaptive application of no-tillage practices， a Meta-analysis was conducted by collecting data from 116 published studies. The effects of no-tillage on aggregate size distribution， mean weight diameter （MWD）， and aggregate-associated C were studied. The results showed that compared with that under tillage， no-tillage significantly increased the proportion of macroaggregates （10.9%） and MWD （12.8%） and decreased the proportion of clay and silt （-15.5%） but had no significant effect on soil microaggregate and aggregate-associated C. The subgroup and Meta regression analysis showed that no-tillage significantly increased the proportion of macroaggregates in Northwest China （17.6%） and MWD in North China （15.4%）. In upland and clay loam， no-tillage increased MWD by 12.6% and 18.4%， respectively. The effect of no-tillage on increasing the proportion of macroaggregates increased with the soil pH. When straw returned， no-tillage significantly increased the proportion of macroaggregates （9.6%） and MWD （11.6%）， but no significant effect of no-tillage on aggregates was found after straw removal. Regarding test duration， short-term （ < 5 a） no-tillage could significantly increase the proportion of macroaggregates， whereas long-term （ > 10 a） no-tillage could improve the MWD. In different soil layers， no-tillage could only significantly improve the aggregate size distribution and MWD in topsoil （0-20 cm） but had no effect in subsoil （ > 20 cm）. In summary， no-tillage could improve aggregate size distribution and stability but had no effect on aggregate-associated C. Production region， soil properties， field management methods， and other factors should be fully considered in production practice to effectively improve the quality of soil aggregates.

[Effect of Biochar on Agricultural Soil Aggregates and Organic Carbon: A Meta-analysis].

As a soil amendment, biochar has been widely used to ameliorate agricultural soil. To ensure the effect of biochar on the carbon sequestration of farmlands in China, a Meta-analysis was carried out via collecting published literatures. We quantitatively analyzed the response of biochar application to soil aggregates, aggregate carbon, and soil organic carbon to different experimental conditions. The results showed that the application of biochar significantly increased the proportion of soil macroaggregates(10.8%) and MWD(13.3%) but had no significant effect on soil microaggregates and silty-clay compared with those in the non-biochar-added treatment. Moreover, biochar addition significantly increased soil organic carbon content(56.9%), with the largest increased area in North China(39.4%), and enhanced intra-aggregate carbon contents of each particle size. Biochar could significantly increase soil organic carbon content under different experimental designs. Compared with that under non-fertilization, biochar combined with fertilization could also significantly improve soil structure and soil fertility. We also found that more than two years of biochar application significantly increased the proportion of macroaggregates(15.7%), MWD(21.2%), macroaggregate carbon(31.7%), and soil organic carbon(40.0%). Meanwhile, biochar produced from crop straw had better soil improvement effects than that of wood and sawdust. Biochar applied in high-nitrogen soil was more beneficial to improve soil stability. Thus, we concluded that biochar could meliorate soil structure and promote the accumulation of soil organic carbon, which was of importance for the fertility maintenance and improvement of the farmland.

[Optimizing Straw Management to Enhance Carbon and Nitrogen Efficiency and Economic Benefit of Wheat-Maize Double Cropping System].

The optimization of annual straw management can improve the yield, income, and carbon and nitrogen efficiency of wheat-maize double cropping systems. Based on a long-term positioning trial started in 2012, five straw management methods were considered, C100 (100% return), C75 (75% return+25% harvest), C50 (50% return+50% harvest), C25 (25% return+75% harvest), and C0 (100% harvest). We analyzed the effects of farmland carbon and nitrogen inputs and their ratios on crop yield, carbon and nitrogen use efficiency, and economic benefits in wheat and maize anniversaries with different straw managements. The results showed that: ① the amount of straw returning to the field resulted in a significant difference in carbon and nitrogen input. The annual carbon and nitrogen inputs from crop residues decreased by 1.76 t·hm-2 and 34.28 kg·hm-2, respectively, with a 25% reduction in straw returning. The C/N ratios under the C100-C0 treatment were 18.62, 17.03, 15.64, 12.54, and 9.61, respectively. ② Grain yield first increased and then decreased with the decrease in the C/N input ratio, and the effect of straw management on wheat yield was greater than that on maize. Compared with that under C100 and C0, the average grain yield of wheat and maize under the C50 treatment increased by 13.34%-13.67% and 16.10%-17.71%, respectively, and the total grain yield of wheat and maize increased by 14.98% and 15.68%. ③ The annual grain yield and carbon agronomy efficiency were the best with the C/N input ratio of 15.64 (in the C50 treatment), which were 15.71% and 0.29 kg·kg-1, respectively. The carbon production efficiency continued to increase with the decrease in the C/N input ratio, and there was a significant negative correlation between them. The nitrogen production efficiency increased first and then decreased with the decrease in the C/N input ratio. The nitrogen production efficiency of the C50 treatment was the highest (0.64 kg·kg-1), which was significantly higher than that of C100 by 32.63%. ④ The C50 treatment had the highest economic income and net income, which were 46200 yuan·hm-2 and 33400 yuan·hm-2, respectively. Compared with that of C100, the economic income of grain and straw feed increased by 5600 yuan·hm-2 and 3200 yuan·hm-2, respectively. In conclusion, the optimal C/N input ratio can be achieved by optimized straw management; 50% straw returning and 50% harvest in a wheat-maize double-cropping intensive production system can promote carbon agricultural efficiency and nitrogen production efficiency and obtain the maximum grain yield and economic benefits.

Effects of traditional Chinese medicine on intestinal mucosal permeability in early phase of severe acute pancreatitis.

BACKGROUND: Traditional Chinese medicine has been used widely for many years in China to treat acute pancreatitis. We have investigated the effects of Dachengqi decoction on intestinal mucosal permeability and outcome in patients with severe acute pancreatitis (SAP). METHODS: Forty patients with sustained SAP that required admission to the surgical intensive care unit were enrolled prospectively in the study. All of these patients were divided randomly into the Dachengqi decoction group (n = 20) and control group (n = 20) on admission. Intestinal permeability was assessed by measuring absorption of two metabolically inert markers, lactulose (L) and mannitol (M), which were administered orally. Serum concentrations of endotoxin (lipopolysaccharide, LPS) and the ratio of lactulose to mannitol in urine (L/M) were detected in all patients. RESULTS: Compared with those in the control group, urinary L/M ratio decreased significantly in the Dachengqi decoction group on the 7th day after admission (P = 0.001). Also, serum concentrations of LPS were reduced on the 5th and 7th day after admission (P = 0.006, P = 0.008, respectively). Incidence of multiple organ dysfunction syndrome (MODS) and pancreatic infection was significantly lower in the Dachengqi decoction group compared with those in the control group (P = 0.038,P = 0.025, respectively). CONCLUSION: Dachengqi decoction may promote the recovery of intestinal mucosal permeability and decrease the incidence of MODS and pancreatic infection in patients with SAP.

Tenuigenin protects cultured hippocampal neurons against methylglyoxal-induced neurotoxicity.

Methylglyoxal is a metabolite of glucose. Since serum methylglyoxal level is increased in diabetic patients, methylglyoxal is implicated in diabetic complications such as cognitive impairment. This study aimed to evaluate the effects of tenuigenin, an active component of roots of Polygala tenuifolia Willdenow, on methylglyoxal-induced cell injury in a primary culture of rat hippocampal neurons. MTT and Hoechst 33342 staining, together with flow cytometric analysis using annexin-V and propidium (PI) label, indicated that tenuigenin pretreatment attenuated methylglyoxal -induced apoptotic cell death in primary cultured hippocampal neurons, showing a dose-dependent pattern. Furthermore, 2, 7-dichlorodihydrofluorescein diacetate was used to detect the level of intracellular reactive oxygen species. Tenuigenin decreased the elevated reactive oxygen species induced by methylglyoxal. In addition, tenuigenin inhibited activation of caspase-3 and reversed down-regulation of the ratio of Bcl-2/Bax, both of which were induced by methylglyoxal stimulation. The results suggest that tenuigenin displays antiapoptotic and antioxidative activity in hippocampal neurons due to scavenging of intracellular reactive oxygen species, regulating Bcl-2 family and suppressing caspase-3 activity induced by methylglyoxal, which might explain at least in part the beneficial effects of tenuigenin against degenerative disorders involving diabetic cognitive impairment.

[Soil nutrient leaching patterns in maize field under different fertilizations: an in situ study].

An in situ field experiment with lysimeter was conducted to study the effects of different fertilizations on the nutrient leaching loss from brown soil in the growth season of summer maize. The results showed that abundant rainfall and irrigation were the main factors affecting the leaching loss. The leaching amount was higher in the early growth period of summer maize, but decreased after then. The difference among different fertilization treatments also decreased with maize growth. Comparing with N fertilization, wheat stalk plus N application intensified the leaching. During the growth period of summer maize, the NO3- -N content in leached water in fertilization treatments had two peaks, while the NH4+ -N content had a trend of increased first and decreased then. The leaching loss of soil N was mainly in the form of NO3- -N. The accumulative leaching loss of NO3- -N was 12.90-46.53 kg * hm(-2), and that of NH4+ -N was 1.66-5.11 kg x hm(-2), both of which increased with increasing N application rate. The leaching rate of soil N was 6.53%-13.07% higher in treatment wheat stalk plus N application than in treatments of N fertilization, and 3.66%-10.10% higher in low N treatments than in high N treatments. The accumulative leaching loss of available P was only 0.148-0.235 kg x hm(-2), while that of available K was 7.08-13.00 kg x hm(-2). In the late growth period of summer maize, wheat stalk plus N application increased the leaching loss of soil available P and K, while nitrogen application affected it slightly.

[Effect of dongchong xiacao capsule on airway inflammation of asthmatic patients].

OBJECTIVE: To investigate the effect of dongchong xiacao capsule on the airway inflammation of asthmatic patients and to explore the relevant mechanism of therapeutic effect of Dongchongxiacao capsule. METHOD: Sixty patients with moderate persistent asthma were randomized into the treatment group (n=30) and the control group (n=30). Inhaled corticosteroid and as-needed beta-agonist were used in the treatment group while this therapy plus dongchong xiacao capsule were used in the control group for two months. Serum IL-4, IFN-gamma, sICAM-1, MMP-9, IgG, IgE level were assessed at randomization and 2 months after randomization. RESULT: The serum level of IgE, sICAM-1, IL-4 and MMP-9 of the treatment group was lowered to a greater degree than that of the control group (P < 0.05 or P < 0.01 ). CONCLUSION: Dongchong xiacao capsule can reduce the serum markers of airway inflammation, which suggests this therapy bares the anti-inflammation effects probably through regulating the balance of TH1/TH2, inhibiting the activity of adherence molecule and reducing IgE production. It may also have the effect of reversing airway remodeling, which needs further research to determine.