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Low wheat grain yield under conservation tillage has been reported, and growth duration could determine the yield. Thus, an 11-year field experiment was conducted to assess the relationship between growth duration and grain yield under different tillage and residue managements. Four treatments were investigated: no-till with residue removal (NT0), conventional tillage with residue removal (CT0), no-till with residue retention (NTR, conservation tillage), and conventional tillage with residue incorporation (CTR). Beginning at 20 days after anthesis (DAA), NTR significantly increased physiological activities, indicating that NTR had a longer growth duration. NTR significantly prolonged growth duration by 2–3 days compared with the other treatments attributed to delayed emergence of seedlings caused by higher soil compaction and moisture under NTR. The CT0 had the highest grain yield on the standard harvest date used in the local area (36 DAA). Whereas the plants in NTR reached physiological maturity (39 DAA), the grain yield in NTR was significantly increased by 7.8–8.8% compared with yield at 36 DAA, and no significant difference was observed between NTR and CT0 due to the increased thousand kernel weight of NTR. Thus, it is practicable for harvesting at physiological maturity in NTR to obtain higher grain yield. [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]

The objective of the current study was to analyze expression levels of synapse differentiation inducing 1-like (SYNDIG1L) and unc-13 homolog C (UNC13C) genes in different tissues, while single-nucleotide polymorphisms (SNPs) of two genes were associated with multiple thoracic vertebrae traits in both Small-tailed Han sheep (STH) and Sunite sheep (SNT). The expression levels of SYNDIG1L and UNC13C were analyzed in the brain, cerebellum, heart, liver, spleen, lung, kidney, adrenal gland, uterine horn, longissimus muscle, and abdominal adipose tissues of two sheep breeds with different thoracic vertebral number (TVN) sheep (T13 groups and T14 groups) by real-time quantitative polymerase chain reaction (RT-qPCR). Meanwhile, the polymorphisms of UNC13C gene g.52919279C > T and SYNDIG1L gene g.82573325C > A in T14 and T13 were genotyped by the Sequenom MassARRAY® SNP assay, and association analysis was performed with the TVN. The results demonstrated that UNC13C gene was extensively expressed in 11 tissues. The expression of UNC13C gene in longissimus muscle of T14 groups of STH was significantly higher than that of T13 groups (P<0.05). SYNDIG1L gene was overexpressed in brain and cerebellum tissues, and the expression level of UNC13C gene in the brain and cerebellum of T13 groups in SNT was significantly higher than that of T14 groups (P<0.01). Association analysis showed that SNPs found in the UNC13C gene had no significant effects on TVN for both two genes. The polymorphism of SYNDIG1L g.82573325C > A was significantly correlated with the TVN in both STH (P<0.05) and SNT (P<0.01). Taken together, the SYNDIG1L gene was related to thoracic vertebral development, and this variation may be potentially used as a molecular marker to select the multiple thoracic vertebrae in sheep. [ABSTRACT FROM AUTHOR]

The ability of an electrochemically active bacterium, Shewanella oneidensis MR-1, to decolorize azo dye cationic red X-GRL (X-GRL) was investigated. S. oneidensis MR-1 showed a high decolorization capability for X-GRL under anaerobic conditions. The Mtr respiratory pathway was proved to be involved in the extracellular decolorization of X-GRL. The decolorization efficiency of S. oneidensis MR-1 was significantly inhibited when the initial X-GRL concentration was over 200 mg L−1. Increasing the inoculum volume of S. oneidensis MR-1 could obviously promote the X-GRL decolorization. The 100 mg L−1 X-GRL and 6% (v/v) inoculum volume were chosen as the optimal parameter. Under such a condition, almost all of X-GRL (100 mg L−1) could be completely reduced after 12-h incubation at the pH range of 5.5-8.0 and temperature range of 30-40°C. Salinity in the medium also affected X-GRL decolorization. Lactate and citric acid were found to be the suitable electron donors for X-GRL decolorization. Although the genotoxicity increased slightly, the phytotoxicity of X-GRL in the decolorization process was significantly reduced by S. oneidensis MR-1. [ABSTRACT FROM AUTHOR]

Exoelectrogenic bacteria (EEB) can transfer electrons to extracellular electron acceptors and have wide applications in environmental bioremediation and bioenergy generation. Thus, methods for effectively probing the exoelectrogenic ability of EEB are highly desirable. In this work, a simple but efficient photometric assay based on the extracellular reduction of high polar dyes was developed to evaluate the microbial exoelectrogenic ability. Methyl orange were proven to be used as a probe for evaluating the exoelectrogenic ability of EEB. Through monitoring the extracellular dye decolorization under anaerobic conditions, this plate-based photometric assay could rapidly measure the exoelectrogenic ability of various EEB. This approach was also able to evaluate the exoelectrogenic capacity of Shewanella oneidensis MR-1 wild-type strain and its Mtr mutants. Furthermore, the exoelectrogenic ability of mixed cultures in microbial fuel cells was correlated with the extracellular dye decolorization. Thus, this work is useful for the practical implementation of microbial exoelectrogenic ability evaluation. [ABSTRACT FROM AUTHOR]

The circadian clock exists in almost all life forms, and is an internal activity generated by organisms adapting to the daily periodic changes of the external environment. The circadian clock is regulated by the transcription-translation-negative feedback loop in the body, which can regulate the activities of tissues and organs. Its normal maintenance is important for the health, growth, and reproduction of organisms. In contrast, due to the season changes of the environment, organisms have also formed annual cycle physiological changes in their bodies, such as seasonal estrus, etc. The annual rhythm of living things is mainly affected by environmental factors such as photoperiod, and is related to gene expression, hormone content, morphological changes of cell and tissues in vivo. Melatonin is an important signal to recognize the changes of photoperiod, and the circadian clock plays an important role in the pituitary to interpret the signal of melatonin and regulate the changes of downstream signals, which plays an important guiding role in the recognition of annual changes in the environment and the generation of the body's annual rhythm. In this review, we summarize the progress of research on the mechanism of action of circadian clocks in influencing annual rhythms, by introducing the mechanisms of circadian and annual rhythms generation in insects and mammals, and in the context of annual rhythms in birds, with the aim of providing a broader range of ideas for future research on the mechanism of annual rhythms influence.

Genetic modification technologies can be used for modifying animal genome to express exogenous genes or affect the function of endogenous genes. In animal breeding, genetic modification technologies allow the rapid generation of germplasms with beneficial traits. It includes traditional genetic modification, virus or sperm carrier-mediated genetic modification and nuclease-mediated genome editing, especially the CRISPR/Cas9, one of the artificial nuclease genome editing technologies, have been applied in genome editing in many domestic animals including sheep (Ovis aries). Compared with conventional strategies used for animal breeding, there is great value for sheep breeding improvement by using genome editing technology, which is more effective and timesaving. In this review, we summarize the approaches of genetic modification in sheep and discuss the possibility of molecular design and breeding of sheep by genome editing technologies. We also identify the potential bottlenecks and challenges of these technologies in sheep breeding.

Purpose: The present meta analysis was designed to determine the effects of macrolides group of antibiotics as local drug delivery agents to scaling and root planing (SRP), compared with SRP alone or plus placebo., Methods: Electronic and manual literature searches were conducted to select randomized controlled trials (RCTs) comparing SRP + macrolides versus SRP alone using the following databases: PubMed, Cochrane Library, Science Direct, EMbase, CNKI, Wanfang database and VIP data until August 2018. Two reviewers independently extracted the data and evaluated the methodological quality of the included studies. RevMan 5.3 was applied for meta analysis., Results: Seven papers were obtained, which included 439 patients with chronic periodontitis.Meta analysis showed that in the two groups, the changes in probing depth（PD）[MD=0.77, 95%CI(0.48-1.05), P<0.00001], clinical attachment loss（CAL）[MD=0.74, 95%CI(0.39-1.10), P<0.0001],plaque index（PI）[MD=0.30, 95% CI(0.17-0.43), P<0.00001]，modified sulcus bleeding index (mSBI)[MD=0.23, 95%CI(0.15-0.32), P<0.00001]at 3 month and 6 month of PD[MD=1.15, 95%CI(0.41-1.89), P=0.002] were significantly different, the difference of CAL[MD=0.92, 95%CI(0.43-1.40), P=0.0002], PI[MD=0.51, 95%CI(0.07-0.95), P=0.02] and mSBI[MD=0.18, 95%CI(0.07-0.29), P=0.002] was also significant (P<0.05)., Conclusions: SRP combined with local macrolides adjuvant treatment for chronic periodontitis is effective in short-term observation.