Search

Abstract Walnut is an important economic tree species while confronting with global environmental stress, resulting in decline in quality and yield. Therefore, it is urgent to elucidate the molecular mechanism for the regulation of walnut response to adversity. The protein phosphatase 2C (PP2C) gene family participates in cellular processes in eukaryotes through reversible phosphorylation of proteins and signal transduction regulation. However, the stress response function of PP2C genes was far to be clarified. Therefore, to understand the stress response mechanism of walnut tree, in this study, a total of 41 PP2C genes with complete ORFs were identified from Juglans regia, whose basic bio-information and expression patterns in response to multiple stresses and ABA were confirmed. The results showed that the ORFs of JrPP2Cs were 495 ~ 3231 bp in length, the predicted JrPP2C proteins contained 164 to 1076 amino acids and the molecular weights were 18,581.96 ~ 118,853.34 Da, the pI was 4.55 ~ 9.58. These JrPP2C genes were unevenly distributed on 14 chromosomes, among which Chr11 and Chr13 contained the most genes. Phylogenetic analysis found that these JrPP2C proteins were classed into 9 subfamilies, among which group F covered most JrPP2Cs. The JrPP2Cs in the same subfamily exhibited similarities in the composition of conserved domains, amino acid sequences of motifs and exon/intron organization in DNA sequences. Each JrPP2C includes 4 ~ 10 motifs and each motif contained 15 ~ 37 amino acids. Among the motifs, motif1, motif2, motif3 and motif8 were most abundant. Most of the JrPP2C genes diversely response to osmotic, cadmium, and Colletotrichum gloeosporioide stress as well as ABA treatments, among which JrPP2C28, JrPP2C17, JrPP2C09, JrPP2C36 were more obvious and deserves further attention. All these results indicated that JrPP2C genes play potential vital roles in plant response to multiple stimulus, and are possibly involved in ABA-dependent signaling pathway.

The main ventilator room of coal mine is remote and difficultly covered by wired network, so as to cause main ventilator monitoring system falling into information island. For above problem, a design scheme of remote wireless monitoring system for coal mine main ventilator based on mobile platform was put forward. The system uses a GPRS DTU to communicate with PLC for collecting field monitoring data, and the data is uploaded to a cloud data sever through GPRS network. On the other hand, mobile client based on Android system accesses the cloud data sever by use of socket communication mode through 3G, 4G or WiFi wireless network, so that users can remotely monitor operation status of coal mine main ventilator anytime and anywhere. The test results verify feasibility of the system.

Aiming at solving the problems of relative sliding between the robot driving wheel and the tube wall and the adaptation of the robot body to the pipe diameter,the pipe robot with the characters of autonomous differential motion and adaptive variable diameter is designed by adopting the single motor to drive. The transmission characteristics of the differential mechanism are analyzed,the force equation of working state for the variable diameter mechanism of pipe robot is theoretically deduced,and the mechanical relation between the driving wheels and pipe wall in robot operation is obtained. The movement model of robot in pipe is built,and the relationship between each variable in the model under the condition of different pose is analyzed. The virtual prototype model of robot operating in combined pipe is built through the simulation analysis. The robot characters of autonomous differential motion is validated. The results indicate that the pipeline robot can through bends without interference,and show a good driving characteristics.

Biological materials, such as bamboo, are naturally optimized composites with exceptional mechanical properties. Inspired by such natural composites, traditional methods involve extracting nanofibers from natural sources and applying them in composite materials, which, however, often results in less ideal mechanical properties. To address this, this study develops a bottom-up nanofiber assembly strategy to create strong fiber-reinforced composite hydrogels inspired by the hierarchical assembly of bamboo. Self-assembled chitosan-sodium alginate nanofibers (CSNFs) are combined with tannic acid (TA) and poly(vinyl alcohol) (PVA) as the interfacial crosslinker and hydrogel matrix, respectively, to emulate the fundamental cellulose-lignin-hemicellulose composition unit of bamboo. Strong interfacial electrostatic interactions and hydrogen bonding form between the functional groups of these components. These molecular interactions can be further reinforced by constructing higher-order structure through stretch-induced orientation. The resulting composite hydrogel achieves good mechanical performance, including a high tensile strength of up to 60.2 MPa and a simultaneous high strength of 48.0 MPa and ultimate strain of 470%. This approach demonstrates a hierarchical bottom-up strategy to construct strong and robust composite hydrogels by effectively leveraging fundamental molecular interactions. By mimicking bamboo's highly integrated structural composition, it offers a promising solution for creating advanced bioinspired materials with excellent mechanical properties. There is interest in mimicking the properties of biological composites in artificial materials, but the hierarchical structures can be challenging to replicate. Here, the authors report the development of a bamboo-inspired hydrogel with favourable mechanical performance. [ABSTRACT FROM AUTHOR]

Granite is a common engineering material that exhibits complex mechanical properties under external loads. This study conducted experimental research and analysis in conjunction with the active monitoring technology of piezoelectric ceramics. A quantitative analysis method for the mechanical properties of rock materials based on piezoelectric health monitoring was established, and for the first time, the piezoelectric monitoring results of rock were mapped and compared with the uniaxial compression performance indicators of rock. In this study, two sets of cyclic impact experiments were conducted on granite samples using a drop hammer. The piezoelectric signals of the granite samples were detected using piezoelectric ceramic active sensing technology. A piezoelectric ceramic damage monitoring method was proposed, and the damage factor of the granite samples was calculated using the wavelet packet energy method. Subsequently, uniaxial compression experiments were performed on the damaged granite samples to obtain mechanical performance data. Finally, a mathematical relationship model was established between the piezoelectric signal and the uniaxial compressive strength of the rocks. It was found that the damage factor of the piezoelectric monitoring signal of the damaged rock were linearly related to the uniaxial compressive strength of the damaged rock. [ABSTRACT FROM AUTHOR]

In order to resolve the issues of low efficiency and poor precision in the traditional finishing process of hardened internal gears, a method is proposed for calculating the profile curves of a drum-shaped grinding tool suitable for mass finishing of hardened internal gears. Additionally, the impact of drum-shaped grinding tool installation errors on the tooth surface deviation of internal gears is analyzed. Firstly, the processing principle for the generation grinding of internal gears by the drum-shaped grinding tool is introduced. Based on differential geometry, meshing theory, and two-degree-of-freedom enveloping method, a mathematical model is developed for the generation grinding of internal gears. Profile curves of the drum-shaped grinding tool are obtained by solving the meshing equation between the drum-shaped grinding tool and the internal gear. Then, the tooth surface equation for the internal gear is derived in the presence of drum-shaped grinding tool installation errors. By discretizing the error tooth surface of the internal gear, the average normal deviation of the tooth surface is calculated. In the end, the distribution of normal deviation on the tooth surface of the internal gear with different drum-shaped grinding tool installation errors is acquired, and the influence of four kinds of installation errors on the tooth surface of the internal gear is analyzed. The sensitive direction is identified for drum-shaped grinding tool installation errors on the tooth surface of the internal gear. Consequently, this research provides a calculation method for the drum-shaped grinding tool fit for high-precision and high-efficiency finishing of mass-produced hardened internal gear and offers a reference for correcting deviation in the tooth surface of internal gear with installation errors of the drum-shaped grinding tool. [ABSTRACT FROM AUTHOR]

Allergic asthma (AA) is closely associated with the polarization of T helper (Th)2 and Th17 cells. Interleukin (IL)-18 acts as an inducer of Th2 and Th17 cell responses. However, expressions of IL-18 and IL-18 receptor alpha (IL-18Rα) in blood Th2 and Th17 cells of patients with AA remain unclear. We therefore investigated their expressions in Th2 and Th17 cells using flow cytometric analysis, quantitative real-time PCR (qPCR), and murine AA model. We observed increased proportions of Th2, Th17, IL-18+, IL-18+ Th2, and IL-18+ Th17 cells in blood CD4+ T cells of patients with AA. Additionally, house dust mite seemed to upregulate further IL-18 expression in Th2 and Th17, and upregulate IL-18Rα expression in CD4+ T, Th2, and Th17 cells of AA patients. It was also found that the plasma levels of IL-4, IL-17A, and IL-18 in AA patients were elevated, and they were correlated between each other. In ovalbumin (OVA)-induced asthma mouse (AM), we observed that the percentages of blood CD4+ T, Th2, and Th17 cells were increased. Moreover, OVA-induced AM expressed higher level of IL-18Rα in blood Th2 cells, which was downregulated by IL-18. Increased IL-18Rα expression was also observed in blood Th2 cells of OVA-induced FcεRIα−/− mice. Collectively, our findings suggest the involvement of Th2 cells in AA by expressing excessive IL-18 and IL-18Rα in response to allergen, and that IL-18 and IL-18Rα expressing Th2 cells are likely to be the potential targets for AA therapy. Collectively, our findings suggest the involvement of Th2 cells in allergic asthma (AA) by expressing excessive IL-18 and IL-18Rα in response to allergen, and that IL-18 and IL-18Rα expressing Th2 cells are likely to be the potential targets for AA therapy. This summary graph shows allergen-induced IL-18 and IL-18Rα expressions in blood CD4, Th2, and Th17 cells of AA. Graphical Abstract [ABSTRACT FROM AUTHOR]

Objective To investigate the effects of allergens on the expressions of IL-18, IL-18BPa and IL-18Rα protein in peripheral blood CD4+ Th1 cells of healthy control subjects (HC) and patients with allergic rhinitis (AR), and on the expressions of IL-18, IL-18BPa and IL-18Rα mRNA in the peripheral blood CD4+ T cells. Methods Blood samples were collected from patients with rhinitis for negative skin prick test (AR-), rhinitis for positive skin prick test (AR+) and HC. Flow cytometry was used to evaluate the effects of allergens on the expressions of IL-18, IL-18BPa and IL-18Rα protein in CD4+ Th1 cells. The expressions of IL-18, IL-18BPa and IL-18Rα mRNA in CD4+ T cells were determined by qPCR. Results Compared with HC, increased IL-18 while decreased IL-18BPa expressions in Th1 cells of AR- and AR+ patients were observed, increased IL-18Rα expression in Th1 cells of AR+ patients was also found. Additionally, allergens induced elevated expression of IL-18Rα protein in Th1 cells of HC, and induced elevated mRNA expressions of IL-18, IL-18BPa and IL-18Rα in isolated blood CD4+ T cells of AR+ patients and HC. Conclusion Allergens may be involved in the pathogenesis of AR by inducing the expressions of IL-18 and IL-18Rα in blood CD4+ Th1 cells. [ABSTRACT FROM AUTHOR]