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【Objective】 Straw mulching and ridge tillage is an improved agronomic technology to sustain crop production in the loess plateau in northwestern China. How their combination impacts water uptake and crop yield is not well understood. This paper is to fill this knowledge gap. 【Method】 The experiment was conducted in a potato field and compared ridge tillage and traditional flatten tillage. For the ridge tillage, there were three mulching treatments: film mulching (PM), locally high straw mulching (RSM9), and locally low straw mulching (RSM6). For the traditional flatten tillage, there were also three treatments: locally high straw mulching (PSM9), locally low straw mulching (PSM6), and full straw mulching (FC). The control is flatten tillage without mulching. 【Result】 ①Compared with CK, mulching increased the yield and WUE of the potato by 11.8%~21.7% and 15.9%~26.7%, respectively. Compared with PSM treatments, RSM treatments increased the yield and WUE of the potato by 1.5% and 1.7%, respectively. Compared with the locally high straw mulching (9 000 kg/hm2), the locally low straw mulching (6 000 kg/hm2) increased the yield and WUE by 6.1% and 6.5%, respectively. ② Compared with CK, local straw mulching increased soil moisture in some regions and reduced it in other regions, but overall, it increased soil water content. The increased soil water storage under different treatments was ranked in the order of RSM6 >PSM6 >RSM9 >PSM9 treatment. ③ Compared with CK, partial straw mulching increased total water consumption, daily water consumption, and water consumption coefficient for potato tuber formation and starch accumulation by 4.6 mm, 0.11 mm/d and 2.7%, respectively. Water consumption during tuber expansion and harvest was greater in RSM than in PSM, while the opposite was true during soil-tuber expansion. 【Conclusion】 Straw mulching can reduce water consumption before tuber expansion, increase water consumption after tuber expansion, balance water consumption and demand during key growth stages, and promote potato growth and development. For all treatments we compared, ridge tillage coupled with partial straw mulching at 6 000 kg/hm2 was most effective.

Objective To explore the effect of hypoxia inducible factor 1α (HIF⁃1α) gene silencing in rat bone mar⁃ row mesenchymal stem cells (BMMSCs) under mechanical distraction on the expression of bone sialoprotein (BSP) and osterix and to provide a new idea for repairing bone defects with BMMSCs. Methods The shRNA sequence was de⁃signed according to the rat HIF⁃1α gene, and the pGMLV⁃SC1RNAi lentiviral vector was cloned after PCR amplifica⁃ tion. After screening positive clones and identifying competent transformed cells by sequencing, 293T cells were pack⁃ aged and titered, rat BMMSCs were transfected and cultured in vitro. Clones with stably silenced HIF⁃1α expression were screened by inverted fluorescence microscopy. The RNAi response experiment was divided into four groups: the blank control group, the HIF⁃1α shRNA group, the negative control group, and the response group. Western blot was used to detect the expression of HIF⁃1α protein in the four groups to verify the response of the target genes and exclude off⁃target effects. A Flexcell FX⁃5000T cell stress loading system was used to intervene in the mechanical stretch of the cells. qRT⁃PCR and Western blot were used to detect the expression of BSP and osterix in the blank control group, HIF⁃ 1α shRNA group, and negative control group. Results The HIF ⁃ 1α shRNA lentiviral vector was successfully con⁃ structed. The results of the RNAi response showed no significant difference in the expression of HIF⁃1α between the re⁃ sponse and the blank control group (P > 0.05). The recombinant lentivirus could effectively silence HIF ⁃ 1α in BMMSCs. After mechanical distraction of the BMMSCs, compared with the blank and negative control groups, the HIF⁃ 1α shRNA group showed significantly increased mRNA and protein expression of the bone⁃related factors BSP and os⁃ terix (P < 0.05); there was no significant difference in the mRNA and protein expression of BSP or osterix between the blank and negative control groups (P > 0.05). Conclusion Silencing HIF⁃1α in BMMSCs under mechanical distrac⁃ tion can promote the expression of BSP and osterix.

Abstract: Soil organic carbon (SOC), total nitrogen (TN), and total phosphorus (TP) are essential nutrients for plant growth. Thus, soil amendments that increase the amounts of these nutrients can improve crop yield in poor growing soils such as Red soils in subtropical China, which were classified as Plinthosols in the WRB (World Reference Base for Soil Resources). It is unknown whether any of the three nutrients are more influential than the others on crop yield. A 30-year-long field experiment was established in 1986 to investigate the response of grain yield to changes in SOC, TN and TP levels, identified by regression equations, due to various fertilizer treatments applied to corn crops grown in red soil. Corn yields varied significantly under four different fertilizer treatments. For most of the experimental years, the two fertilizer treatments of application of manure combined with inorganic nitrogen, phosphorus, and potassium (NPKM) and a higher rate of NPK (HNPK) fertilizer produced significantly higher yields than the control (no addition of fertilizer, CK) by 441-548 and 380-703%, respectively. Differences between yields increased over time, particularly between NPKM and CK treatments. The long-term application of NPKM increased SOC, TN and TP contents more so than the other treatments and contents were greater than those in the CK by 48.6-57.1, 26.4-37 and 81.6-142%, respectively. There were no significant differences between the treatments with the low and high rates of NPK (LNPK and HNPK). Additional results showed that NPKM raised the C : N ratio and lowered the C : P ratio. The relationships between SOC, TN, TP and grain yield were best represented by the Michaelis-Menten equation rather than the simple linear equation. Moreover, the equations estimated different maximum yields of corn; yields estimated by SOC and TP were higher than the yield estimated by TN. Furthermore, The estimated maximum yield that could be attained is at a C : N ratio of 10.22 in red soil. Therefore, SOC and TP are likely the more important nutrients to consider altering in soil management of red soil. [ABSTRACT FROM AUTHOR]

Aim: Central nervous system (CNS) metastasis is a major obstacle in the treatment of leukemia, and the underlying mechanisms of leukemia CNS metastasis are not fully understood. The present study is an investigation of the role of the CNS microenvironment in leukemia CNS metastasis. Methods: Analog blood-brain barrier (BBB) was set by coculturing human brain microvascular endothelial cells (HBMVECs) and leukemia cells (U937 and IL-60), as well as HBMVECs and sera from leukemia patients, in vitro. The permeability of the HBMVEC monolayer and the levels of tight junction proteins, cytokines and chemokines (C&Ckines) were measured. Results: The permeability of HBMVECs increased when cocultured with leukemia sera. The expression of C&Ckines was significantly upregulated in HBMVECs cocultured with leukemia sera or leukemia cells, compared to the normal sera (P<0.05, respectively). Specifically, significantly higher levels of vascular endothelial growth factor A (VEGF-A) and matrix metalloprotease 9 (MMP-9) were found in HBMVECs and leukemia cells/sera coculturing systems. Conclusion: Both leukemia cells and the molecules in leukemia sera play an important role in leukemia CNS metastasis. VEGF-A and MMPs may be the main factors resulting in the degradation of the BBB and inducing the CNS migration of leukemia cells. [ABSTRACT FROM AUTHOR]

Photochromic phenylhydrazones are one of the most promising candidates for a photoswitchable fluorescent probe with potential applications in various fields, but mechanistic understanding of the origin of this unique behavior is limited. In this work, we explored the emission nature and switching mechanism of a model phenylhydrazone-based fluorescent photoswitch, DMA-PHA, by means of TD-DFT and CASPT2 calculations. The fluorescence-emitting Z configuration of DMA-PHA does not involve an excited-state intramolecular proton transfer process since the resonance effect between the DMA group and the rest part of the molecule in the excited state strengthens the hydrogen bond and thus stabilizes the emissive state. The light-induced fluorescence toggling results from E ↔ Z interconversion driven by an out-of-plane C═N bond torsion and assisted by a N-N single bond rotation, which in total lead to a charge separation process losing the fluorescence activity. The N-N bond rotation in phenylhydrazone further enhances the competitive nonradiative decay and reduces the photoisomerization yields. The theoretical results will provide the guidance for the rational design of novel and improved photoswitchable fluorescent probes with desired performances.

Life cycle timing is critical for yield and productivity of Brassica napus (rapeseed) cultivars grown in different environments. To facilitate breeding for earliness traits in rapeseed, SNP loci and underlying candidate genes associated with the timing of initial flowering, maturity and final flowering, as well as flowering period (FP) were investigated in two environments in a diversity panel comprising 300 B. napus inbred lines. Genome-wide association studies (GWAS) using 201,817 SNP markers previously developed from SLAF-seq (specific locus amplified fragment sequencing) revealed a total of 131 SNPs strongly linked (P < 4.96E-07) to the investigated traits. Of these 131 SNPs, 40 fell into confidence intervals or were physically adjacent to previously published flowering time QTL or SNPs. Phenotypic effect analysis detected 35 elite allelic variants for early maturing, and 90 for long FP. Candidate genes present in the same linkage disequilibrium blocks (r2>0.6) or in 100 kb regions around significant trait-associated SNPs were screened, revealing 57 B. napus genes (33 SNPs) orthologous to 39 Arabidopsis thaliana flowering time genes. These results support the practical and scientific value of novel large-scale SNP data generation in uncovering the genetic control of agronomic traits in B. napus, and also provide a theoretical basis for molecular marker-assisted selection of earliness breeding in rapeseed., (© The Author 2017. Published by Oxford University Press on behalf of Kazusa DNA Research Institute.)

T-bet plays an important role in immunoregulation; it induces the differentiation of Th1 together with the homeobox transcription factor gene Hlx. Recent studies show that T-bet and Th1-associated factors are critical in regulating tumor development. However, the contributions of Hlx in the occurrence and development of cancer remain unknown. In this study, the Hlx, T-bet, Runx3, and IFN-γ were measured in PBMC from patients with gastric cancer and the correlation between Hlx and T-bet or IFN-γ was assessed. The expression levels of Hlx, T-bet, and IFN-γ were significantly decreased, and there was a positive correlation between Hlx and T-bet or IFN-γ. In addition, the Runx3 expression was also downregulated with the lower T-bet mRNA level. These results suggested that the decreased Hlx expression was closely associated with T-bet and Runx3 downregulations and may contribute to the development of gastric cancer.