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The 1,2-diamine motif is prevalent in natural products, small-molecule pharmaceuticals, and catalysts for asymmetric synthesis. Transition metal catalyzed alkene diazidation has evolved to be an attractive strategy to access vicinal primary diamines but remains challenging, especially for practical applications, due to the restriction to a certain type of olefins, the frequent use of chemical oxidants, and the requirement for high loadings of metal catalysts (1 mol % or above). Herein we report a scalable Cu-electrocatalytic alkene diazidation reaction with 0.02 mol % (200 ppm) of copper(II) acetylacetonate as the precatalyst without exogenous ligands. In addition to its use of low catalyst loading, the electrocatalytic method is scalable, compatible with a broad range of functional groups, and applicable to the diazidation of α,β-unsaturated carbonyl compounds and mono-, di-, tri-, and tetrasubstituted unactivated alkenes.

BRI1-EMS-SUPPRESSOR 1 (BES1) transcription factor is closely associated with the brassinosteroid (BR) signaling pathway and plays an important role in plant growth and development. SLB3 is a member of BES1 transcription factor family and its expression was previously shown to increase significantly in tomato seedlings under drought stress. In the present study, we used virus-induced gene silencing (VIGS) technology to downregulate SLB3 expression to reveal the function of the SLB3 gene under drought stress further. The downregulated expression of SLB3 weakened the drought tolerance of the plants appeared earlier wilting and higher accumulation of H2O2 and O2−·, decreased superoxide dismutase (SOD) activity, and increased proline (PRO) and malondialdehyde (MDA) contents and peroxidase (POD) activity. Quantitative real-time PCR (qRT-PCR) analysis of BR-related genes revealed that the expression of SlCPD, SlDWARF and BIN2-related genes was significantly upregulated in SLB3-silenced seedlings under drought stress, but that the expression of TCH4-related genes was downregulated. These results showed that silencing the SLB3 gene reduced the drought resistance of tomato plants and had an impact on the BR signaling transduction which may be probably responsible for the variation in drought resistance of the tomato plants.

Zinc finger-homeodomain proteins (ZF-HDs) are transcription factors that regulate plant growth, development, and abiotic stress tolerance. The SL-ZH13 gene was found to be significantly upregulated under drought stress treatment in tomato ( Solanum lycopersicum ) leaves in our previous study. In this study, to further understand the role that the SL-ZH13 gene plays in the response of tomato plants to drought stress, the virus-induced gene silencing (VIGS) method was applied to downregulate SL-ZH13 expression in tomato plants, and these plants were treated with drought stress to analyze the changes in drought tolerance. The SL-ZH13 silencing efficiency was confirmed by quantitative real-time PCR (qRT-PCR) analysis. In SL-ZH13 -silenced plants, the stems wilted faster, leaf shrinkage was more severe than in control plants under the same drought stress treatment conditions, and the mean stem bending angle of SL-ZH13-silenced plants was smaller than that of control plants. Physiological analyses showed that the activity of superoxide dismutase (SOD) and peroxidase (POD) and the content of proline (Pro) in SL-ZH13 -silenced plants were lower than those in control plants after 1.5 and 3 h of drought stress treatment. The malondialdehyde (MDA) content in SL-ZH13 -silenced plants was higher than that in control plants after 1.5 and 3 h of drought stress treatment, and H 2 O 2 and O 2 – · accumulated much more in the leaves of SL-ZH13- silenced plants than in the leaves of control plants. These results suggested that silencing the SL-ZH13 gene affected the response of tomato plants to drought stress and decreased the drought tolerance of tomato plants.

Silver based composites containing different amounts of WS2 were prepared by hot-pressing method and their tribological behaviors were investigated against coin silver under humid air, dry nitrogen and vacuum on a ball-on-disk tester with normal load of 5 N. The components of composites, microstructure of debris and worn surface were characterized using XRD SEM, EDS and XPS. It is demonstrated that environmental conditions significantly affect the tribological behavior of silver based composites. The friction coefficient is the highest in humid air, and the lowest in dry nitrogen. It is found that the friction and wear behavior of the composites are strongly depended on the characteristics of the lubrication film forming in different operating environments, such as thickness and composition. In addition, it is indicated that the dominant wear mechanisms of silver based composites are abrasive wear and delamination under different conditions.

The mechanical and tribological properties of hot-pressed copper-based composites containing different amounts of graphene nanosheets (GNSs) are compared with those of copper–graphite (Gr) composites fabricated by the same method. The results show that the Cu–GNSs composites exhibit higher relative density, microhardness and bending strength compared with Cu–Gr composites with the same volume fraction of GNSs and Gr. Moreover, the friction coefficients and wear rates reduce significantly by the addition of GNSs, whereas the limited impact on reducing friction and wear is found on graphite. The abrasive and delamination wear are the dominant wear mechanisms of the composites. It is believed that the superior mechanical and tribological performances of Cu–GNSs composites are attributed to the unique strengthening effect as well as the higher lubricating efficiency of graphene nanosheets compared with those of graphite, which demonstrates that GNS is an ideal filler for copper matrix composites, acting as not only an impactful lubricant but also a favorable reinforcement.

Cf-12 is an effective gene for resisting tomato leaf mold disease caused by Cladosporium fulvum (C. fulvum). Unlike many other Cf genes such as Cf-2, Cf-4, Cf-5, and Cf-9, no physiological races of C. fulvum that are virulent to Cf-12 carrying plant lines have been identified. In order to better understand the molecular mechanism of Cf-12 gene resistance response, RNA-Seq was used to analyze the transcriptome changes at three different stages of C. fulvum infection (0, 4, and 8 days post infection [dpi]). A total of 9100 differentially expressed genes (DEGs) between 4 and 0 dpi, 8643 DEGs between 8 and 0 dpi and 2547 DEGs between 8 and 4 dpi were identified. In addition, we found that 736 DEGs shared among the above three groups, suggesting the presence of a common core of DEGs in response to C. fulvum infection. These DEGs were significantly enriched in defense-signaling pathways such as the calcium dependent protein kinases pathway and the jasmonic acid signaling pathway. Additionally, we found that many transcription factor genes were among the DEGs, indicating that transcription factors play an important role in C. fulvum defense response. Our study provides new insight on the molecular mechanism of Cf resistance to C. fulvum, especially the unique features of Cf-12 in responding to C. fulvum infection.

This article focuses on modeling and intelligent control of car following behavior. The car following behavior has been modeled by nonlinear equations, and this model has been validated by measured data of different drivers and cars and has been simulated in MATLAB software. An ANFIS controller for car following behavior has been designed and simulated in this paper. The simulated relative distance between the LV and the FV and relative speed measured by the radar sensor are sent into the ANFIS controller to simulate the car following performance. The simulation results show that the ANFIS controller has better effect than the real drivers to obtain objective of setting the least relative speed and safe distance. The presented controller can be used in analyzing and correcting driver’s behaviors, developing cooperative systems and safety systems of driving, intelligent car and traffic flow.

In this article a new structure of a force sensor based on piezoelectric materials is proposed. The design and choice of measuring principle is based on the direct piezoelectric effect, for the measurement of the dynamic force, and on the analysis of the electromechanical impedance technique, for measuring the static force. This technique is based on the measurement of modes of the structure. Indeed, the application of stress on the structure will cause changes in the modes of the structure and appearance of new eigenmodes. Thus far these methods should allow for measurement of static force applied.

RAPD and SSR were applied to assess genetic diversity in 61 tomato varieties from different species ( Solanum lycopersicum L., hirsutum. Humb L., pimpinellifolium Miller L., chilense Dun. L., chmielenskii L., peruvianum Miller L., parvuflorum Miller L.). 2 062 and 869 clear fragments were amplified by RAPD and SSR, respectively. On the other hand, more polymorphic products were found by SSR as compared to RAPD, i.e., 100 and 43.84%, respectively. In addition, a higher value of the average similarity coefficient and lower PIC value were reflected in RAPD (0.79, 0.407) compared to SSR (0.56, 0.687). It can be inferred that SSR was a higher effective marker than RAPD to assess genetic diversity in tomato accessions. Similarly, the genetic base of tomato varieties in Chinese market was narrow. It is suggested that wild tomato varieties should be used to enrich the genetic base of the cultivated tomato varieties.

To explore feasibility for entrance of the contrast agent Sonovue and Feridex into the aortal wall.17 male Japanese giant ears rabbits (common grade), including 11 atherosclerosis (AS) animal models fed with food containing high-content lipid and normal animals fed with common food as control. Respectively, 10 animals in the AS group and 6 animals in the normal group were selected in a random way to undergo ultrasound-mediated microbubble destruction (UMMD) and no ultrasound-mediated microbubble destruction (-UMMD) half and half. One animal was administrated with double doses of Feridex. After general anesthesia, MR plain scan and intravenous injection of Feridex 100 micromol Fe/kg, immediately ultrasound focused on the front wall of the aortic arch, which underwent UMMD at the pressure of 3.5 Mpa with MI1.2 while 10 ml solution (Sonovue + normal saline)was injected intravenously at the speed of 0.5 ml/min FOR 20 min. 3T magnetic resonance (MR) was performed with a moderately T2* weighted gradient sequence. Enhanced scan were performed for 1 h, 24 h, 48 h, 72 h and after killing the animal. then the specimen were delivered to conduct optical and electronic microscope examination. Variance test for the re-measured data was adopted to verify the data obtained in every group.The effect of UMMD group on SPIO particles entrance into the aortal wall is of marked significance (P = 0.0004) statistically. The effect of UMMD on distribution in the vessel wall is of statistical significance (P = 0.01), more particles in the dventitia. Gas or microbubbles were found to enter into the intima, media of the aorta, and verified by Oil Red O staining. After staining the findings of iron particle in the cell and out of the cell are different.UMMD may facilitate entrance of those SPIO particles with a bigger diameter and microbubbles into the aortal wall. This discovery may provide a new solution for penetration of complex macromolecule probes and gene-carried drug through the tunica intima of the aorta.