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In this paper, a mathematical model of the relationship between the amount of various components of recycled concrete and its compressive strength is established by using a large number of experimental data on the strength performance of recycled concrete and BP artificial neural network technology. In this paper, the influence trend of water binder ratio and aggregate substitution rate on the strength of recycled concrete is studied by this model. Taking recycled concrete with different recycled aggregate as the research object, a nonlinear structural model reflecting the mapping relationship between mix proportion and strength of recycled concrete is established in this paper. In this paper, the predicted values of the model are compared with the experimental data. The research shows that the strength model of recycled concrete based on BP neural network established in this paper can predict the compressive strength of recycled concrete at the corresponding age according to the mix proportion of recycled concrete, and the prediction accuracy is high. The application of BP neural network effectively reduces the times of a large number of repeated mix proportion test when preparing recycled concrete in practical engineering, reduces the waste of human and material resources, and has good economic benefits.

Professional certification is an important way to promote professional construction and the quality of personnel training. Undergraduate thesis is an important part of comprehensive training for agricultural students, and it is also one of the "prescribed actions" of professional certification examination. Based on the perspective of professional certification, taking the graduation thesis of Agronomy Major of Southwest University in recent five years as an example, this paper analyzes the reasons for the gap between the quality of graduation thesis and professional certification standards, and puts forward six paths to improve the quality of graduation thesis of agricultural undergraduates, such as more independent topic selection, more diversified forms, multilink submission materials online, relaxed time, and adding graduation thesis index We should guide the project, link up the construction of professional core courses, build a "learning community between teachers and students".

In the agriculture industry, adventitious root formation is a core issue of plants asexual propagation. However, the underlying molecular mechanism of adventitious root formation is far beyond understanding. In present study we found that target of rapamycin (TOR) signaling plays a key role in adventitious root formation in potato and Arabidopsis. The core components of TOR complex including TOR, RAPTOR, and LST8 are highly conserved in potato, but the seedlings of potato are insensitive to rapamycin, implying FK506 Binding Protein 12 KD (FKBP12) lost the function to bridge the interaction of rapamycin and TOR in potato. To dissect TOR signaling in potato, the rapamycin hypersensitive potato plants (BP12-OE) were engineered by introducing yeast FKBP12 (ScFKBP12) into potato. We found that rapamycin can significantly attenuate the capability of adventitious root formation in BP12-OE potatoes. KU63794 (KU, an active-site TOR inhibitor) combined with rapamycin can more significantly suppress adventitious root formation of BP12-OE potato than the single treatments, such as KU63794 or rapamycin, indicating its synergistic inhibitory effects on potato adventitious root formation. Furthermore, RNA-seq data showed that many genes associated with auxin signaling pathway were altered when BP12-OE potato seedlings were treated with rapamycin + KU, suggesting that TOR may play a major role in adventitious root formation via auxin signaling. The auxin receptor mutant tir1 was sensitive to TOR inhibitors and the double and quadruple mutants including tir1afb2, tir1afb3, and tir1afb1afb2afb3 displayed more sensitive to asTORis than single mutant tir1. Consistently, overexpression of AtTIR1 in Arabidopsis and potato can partially overcome the inhibitory effect of asTORis and promote adventitious root formation under asTORis treatments. These observations suggest that TOR signaling regulates adventitious root formation by mediating auxin signaling in Arabidopsis and potato.

The Tianshuihai lead–zinc deposit, located in the Karakorum Mountains, Xinjiang Province, NW China, was discovered in 2011. The ore bodies occur within the clastic rocks in the lower part of the Cretaceous Tielongtan Group. The main ore body of the mineral deposit is 450 m in length, 5.24–47.5 m in thickness and 201 m in depth. It strikes NE and dips SE at about 50°, which is consistent with the occurrence of its surrounding rock layers. This lead–zinc deposit with an average Pb grade of 6.65% (ranging from 0.5% to 58.5%) has potential for becoming a large-scale deposit. The discovery of this deposit is a result of a stepwise multi-scale geochemical mapping program including an original geochemical exploration with very low density (1 point/16 km 2 ), followed by general exploration (4 points/km 2 ), then mineral prospecting (125 points/km 2 ), and finally with drilling verification. As a consequence, this is a successful case of multi-scale geochemical mapping for exploration of metallic mineral resources.

In the present study, we investigated the immunoregulatory effects of Stemona tuberose(ST) in an in vitro and in ovalbumin (OVA)-induced asthma model. Murine spleen cells were isolated from normal and OVA-treated mice and the cytokine levels from T-cells in supernatants were determined by enzyme-linked immunosorbent assay (ELISA). The results of the in vitro experiments indicated that ST modulated the balance between Th1 and Th2 cytokines. In addition, in the in vivo experiments we showed that ST significantly increased the levels of interleukin-2 (IL-2) and interferon-γ (IFN-γ) and decreased those of IL-4, IL-5 and IL-13, as compared with OVA control. Reverse transcription-polymerase chain reaction (RT-PCR) was carried out to determine the GATA-3/T-bet ratio. Results showed that ST modulated the Th2/Th1 imbalance by inhibiting GATA-3 and enhancing T-bet. The hematoxylin and eosin (H&E) stain studies on lung tissues indicated that ST had potential inhibitory ability on inflammation cells. Taken together, these findings suggest that the ethanol extract of ST might have compounds with immunomodulation potential. Key words: Stemona tuberose, immunoregulation, allergic asthma, T-cell cytokines.

Human health, food safety, and agriculture have been threatened by oomycetic diseases caused by notorious pathogenic oomycetes. Chemical oomyceticides are the main approaches in control of pathogenic oomycetes. However, the overused chemical oomyceticides have resulted in serious environmental pollution and drug resistance. The eco-friendly bio-oomyceticides are required for sustainable development through screening synergistic drug combinations. In this study, Phytophthora nicotianae (P. nicotianae), as one of the most destructive oomycetic diseases in agriculture, was used as a model system to screen the novel bio-oomyceticides based on drug combination. The results showed that treatment of melatonin or ethylicin (IUPAC Name: 1-ethylsulfonylsulfanylethane) alone displayed similar phenotypes such as the inhibition of the hyphal growth, reduction of the cell viability, and suppression of the virulence of P. nicotianae. Importantly, melatonin and ethylicin shared the same targets of interfering with the amino acid metabolism, overexpressing apoptosis-inducing factor, and dysregulating the virulence-related genes. Furthermore, strong synergism against P. nicotianae was induced by combining melatonin with ethylicin. Under treatment of the combination of melatonin and ethylicin, the expression of genes associated with amino acid, the apoptosis-inducing factor, and the virulence-related genes was much more significantly dysregulated than that of single drug treatment. Thus, the tobacco black shank caused by P. nicotianae can be successfully controlled using the combination of melatonin and ethylicin. These observations suggest that the synergistic effect based on the combination of melatonin and ethylicin is an eco-friendly alternative for the control of the destructive oomycetic diseases.

Target of rapamycin (TOR), a master sensor for growth factors and nutrition availability in eukaryotic species, is a specific target protein of rapamycin. Rapamycin inhibits TOR kinase activity via FK506 binding protein 12 kDa (FKBP12) in all examined heterotrophic eukaryotic organisms. In Arabidopsis, several independent studies have shown that AtFKBP12 is non-functional under aerobic condition, but one study suggests that AtFKBP12 is functional during anaerobic growth. However, the functions of AtFKBP12 have never been examined in parallel under aerobic and anaerobic growth conditions so far. To this end, we cloned the FKBP12 gene of humans, yeast, and Arabidopsis, respectively. Transgenic plants were generated, and pharmacological examinations were performed in parallel with Arabidopsis under aerobic and anaerobic conditions. ScFKBP12 conferred plants with the strongest sensitivity to rapamycin, followed by HsFKBP12, whereas AtFKBP12 failed to generate rapamycin sensitivity under aerobic condition. Upon submergence, yeast and human FKBP12 can significantly block cotyledon greening while Arabidopsis FKBP12 only retards plant growth in the presence of rapamycin, suggesting that hypoxia stress could partially restore the functions of AtFKBP12 to bridge the interaction between rapamycin and TOR. To further determine if communication between TOR and auxin signaling exists in plants, yeast FKBP12 was introduced into DR5::GUS homozygous plants. The transgenic plants DR5/BP12 were then treated with rapamycin or KU63794 (a new inhibitor of TOR). GUS staining showed that the auxin content of root tips decreased compared to the control. DR5/BP12 plants lost sensitivity to auxin after treatment with rapamycin. Auxin-defective phenotypes, including short primary roots, fewer lateral roots, and loss of gravitropism, occurred in DR5/BP12 plants when seedlings were treated with rapamycin+KU63794. This indicated that the combination of rapamycin and KU63794 can significantly inhibit TOR and auxin signaling in DR5/BP12 plants. These studies demonstrate that TOR is essential for auxin signaling transduction in Arabidopsis.

The thermo-sensitive period and the critical temperature of fertility transition of C49S, a principal thermo-photosensitive genic male sterile line in two-line hybrid wheat, was studied in the growth chambers for controlling temperature and photoperiod. The seeds were sown on different time for some years. The results showed that the thermo-sensitive period in fertility expression of C49S was from PMC formation stage to mature pollen stage, and there were two most sensitive stages to temperature on fertility expression. One was the PMC meiosis stage, and the other was the middle microspore stage. The critical temperatures evoking a complete male sterility were the mean minimum temperature at PMC meiosis stage (Tmin1), the mean temperature at microspore stage (T2) and the mean minimum temperature at microspore stage (Tmin2) lower than 8.5 degrees C, 13.5 degrees C and 10.5 degrees C, respectively. The critical temperatures keeping a nearly normal male fertility Tmin1 and T2 and Tmin2 were higher than 11.5 degrees C, 15.0 degrees C and 12.5 degrees C, respectively. The value as well as the conditions and the risks of thermo-photo-sensitive genic male sterile line of wheat applied to hybrid wheat were evaluated in this paper.