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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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

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.

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.

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.

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.