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Intimal hyperplasia is a common feature of vascular remodelling disorders. Accumulation of synthetic smooth muscle cell (SMC)-like cells is the main underlying cause. Current therapeutic approaches including drug-eluting stents are not perfect due to the toxicity on endothelial cells and novel therapeutic strategies are needed. Our preliminary screening for dysregulated cyclic nucleotide phosphodiesterases (PDEs) in growing SMCs revealed the alteration of PDE10A expression. Herein, we investigated the function of PDE10A in SMC proliferation and intimal hyperplasia both in vitro and in vivo.RT-qPCR, immunoblot, and in situ proximity ligation assay were performed to determine PDE10A expression in synthetic SMCs and injured vessels. We found that PDE10A mRNA and/or protein levels are up-regulated in cultured SMCs upon growth stimulation, as well as in intimal cells in injured mouse femoral arteries. To determine the cellular functions of PDE10A, we focused on its role in SMC proliferation. The anti-mitogenic effects of PDE10A on SMCs were evaluated via cell counting, BrdU incorporation, and flow cytometry. We found that PDE10A deficiency or inhibition arrested the SMC cell cycle at G1-phase with a reduction of cyclin D1. The anti-mitotic effect of PDE10A inhibition was dependent on cGMP-dependent protein kinase Iα (PKGIα), involving C-natriuretic peptide (CNP) and particulate guanylate cyclase natriuretic peptide receptor 2 (NPR2). In addition, the effects of genetic depletion and pharmacological inhibition of PDE10A on neointimal formation were examined in a mouse model of femoral artery wire injury. Both PDE10A knockout and inhibition decreased injury-induced intimal thickening in femoral arteries by at least 50%. Moreover, PDE10A inhibition decreased ex vivo remodelling of cultured human saphenous vein segments.Our findings indicate that PDE10A contributes to SMC proliferation and intimal hyperplasia at least partially via antagonizing CNP/NPR2/cGMP/PKG1α signalling and suggest that PDE10A may be a novel drug target for treating vascular occlusive disease.

In order to realize lightweight manufacturing of gear parts, the cold extrusion forming process of steel-aluminum composite metal gears was studied. Using numerical simulation software Deform, the effects of five steel rings with different thicknesses on forming pressure and shapes of formed forgings were compared. The simulation results showed that final forming force of the gear was smaller and the radial deformation degree of steel ring was larger when using thinner steel ring. This radial deformation degree was characterized by height difference between the convex and the concave in steel-aluminum bonding position, and great deformation presented as obvious bimetal occlusion. The physical experiment verified numerical simulation results, and meanwhile found that the thickness of steel sleeve had an important effect on bonding tightness of steel-aluminum contact surface of formed part and the composite gear formed by thin steel ring had a gap at tooth tip between steel and aluminum. Comprehensive analysis suggested the ratio of outer diameter to inner diameter (R0/Ri) of steel sleeve reflected different deformation regularity. Consequently, the thick-walled axial compression model was used to analyze forming process of steel sleeve with high R0/Ri ratio, and the thin-walled cylindrical shell model was used to analyze forming process of steel sleeve with low R0/Ri ratio. The axial compression of thin cylindrical shell produced local buckling deformation, which led to the appearance of gaps in steel-aluminum bonding position. In order to avoid gaps in bimetal contact surface, the influence of steel ring thickness on deformation coordination of two metals should be fully considered in cold extrusion of steel-aluminum composite metal gear.

In this paper, high manganese steel with cone crushing motor cone lining plate is selected, and the sliding friction and wear experiments of 50 N, 100 N and 150 N loads were carried out in different media environments (dry friction, deionized water solution, 3.5 wt.% NaCl solution) by using Rtec-MFT 5000 tester. The wear mechanism was studied by the data collected by friction and wear experiments and the morphology analysis of the microstructure by scanning electron microscopy (SEM). The results showed that the friction coefficient of high manganese steel was the maximum in dry friction condition, and the minimum in deionized water solution. Under the same load, the wear volume in 3.5 wt.% NaCl solution was always the largest, followed by the dry friction in deionized aqueous solution. This was because the overall wear was accelerated after adding water, especially with ionic solutions containing salts, the double damage of electrochemical corrosion and physical wear would occur, resulting in more serious wear. According to the pictures of the surface microstructure, it was found that the microstructure damage of the high manganese steel sample in 3.5% NaCl solution was the most serious, and the damage was the least in deionized aqueous solution. In conclusion, the high manganese steel material had the best wear resistance in deionized aqueous solution, followed by dry friction, and the worst wear resistance in 3.5 wt.% NaCl solution.

The influence of pre-heat treatment and carburizing quenching on microstructure and properties in steering gear is studied. The CCT curve and TTT curve of 20CrMnTiH are calculated by JMatPro software. According to the phase transformation theory of undercooled austenite, the pre-heat treatment process is designed and the carburizing and quenching experiments are carried out in a gas carburizing furnace. Results show that the undercooled austenite begins to transform at 814.1 °C and shows unstable at 650 °C, at which the phase transformation speed is the fastest; By controlling the cooling rate of our designed air cooling system, transformation temperature and transformation time during the undercooled austenite transformation, the metallographic structure of axle teeth after pre-heat treatment can reach grade 1, with the brinell hardness distribution is 159HB-166HB and the hardness difference less than 7HB. After carburizing and quenching the carbide grade in the gear surface can reach to grade 1. The acicular martensite and retained austenite can also reach to grade 3. In the surface of the gear the hardness is 704HV. With the request of the engineering technical standard of 0.7mm-0.9mm, the effective hardened layer depth is about 0.85 mm. This research provides a technical basis for the fatherly research on distortion characteristics.

The AC (alternating current) servo axial-infeed incremental warm rolling equipment was studied in this paper on the basis of the integration of process and equipment. Firstly, the details of each subsystem are discussed to demonstrate the features of the novel rolling equipment. Next, the performance of the AC servo axial-infeed incremental warm rolling equipment is investigated through the experiments. The whole rolling process of spline shaft lasted about 2 min in the rolling equipment, which is greatly reduced compared with traditional processes. The testing results of rotational speed show that the root mean square error (RMSE) values of speed are less than 5%, which indicate that the rolling equipment can ensure the precision of rotational speed through servo system. Finally, the simulated production of spline shafts was carried out on the rolling equipment. According to the dimensional measurement results of the formed spline shaft, the percent of pass is 80% for the simulated production. In addition, the microstructure observation and the hardness measurement proved that the formed spline shafts possess an excellent performance.

To overcome the poor conductivities and promote the application in the biosensors of metal-organic frameworks (MOFs), a simple approach was employed to improve their overall conductivity by adjusting the metal centers of MOFs and coating conductive polypyrrole (PPy) in the work. An unprecedented molybdenum oxide-based three-dimensional MOFs with helical channels (CuTRZMoO4) was synthesized based on MoO4−, Cu2+ ions and 1,2,3-trz for the first time, then combined with PPy to fabricate hybrid composites (CuTRZMoO4@PPy-n) with both advantages. The CuTRZMoO4 modified glassy carbon electrode show high sensitivity for detecting the neurotransmitter dopamine (DA), and the CuTRZMoO4@PPy-2 modified glassy carbon electrode has the highest catalytical activity to DA with the linear detection range from 1 μM to 100 μM and the detection limit of 80 nM (S/N = 3) by differential pulse voltammetry (DPV). Moreover, the developed biosensor has good selectivity, reproducibility and stability. The concept behinds the new architecture to modify electrodes should promote the further development of MOF-based biosensors.

In order to define the role of oxalic acid (OA) in the invasion of Botrytis cinerea in tomato plants, the OA induction of resistance related to oxalate oxidase (O×O) and germin was examined. In greenhouse experiments, OA at 3 mmol/L significantly induced resistance in tomato plants against B. cinerea strains B05.10 and T4, reducing lesion size of 37.55% and 24.91% by compared with distilled water control, respectively, while 20 mmol/L OA increasing by 36.14% and 41.48%. OA contents were 98 and 46 µg/mL when tomato plants were infected by B. cinerea strains B05.10 and T4, respectively. To define the molecular-genetic mechanisms, we compared the gene expression under four different conditions: 3 mmol/L OA-treated plants, 20 mmol/L OA-treated plants, B. cinerea strain B05.10-infected plants (B05.10 Inf plants) and B. cinerea strain T4-infected plants (T4 Inf plants). In 3 mmol/L OA-treated plants, the expressions of O×O and Germin peaked at 48 h after spraying, with approximate threefold and 18-fold increase compared with the control expression, respectively. In T4 Inf plants, the expression (mRNA accumulation) of O×O and Germin reached the highest levels at 24 h after inoculation, with 3- and 13-times that immediately after inoculation, respectively. In total, these findings suggest that elevated levels of OA correlated with increased fungal invasion and lower OA induced resistance in tomato plants by increasing expressions of O×O and Germin.

A new bivanadium-capped saturated Keggin polyoxometalates based hybrid compound, H[VMo8VIMo4VO40(VO)2](HBIX)3 (BIX = 1,3-bis(imidazol-1-ylmethyl)benzene) (VMo12V2), was hydrothermally synthesized by surfactant trea-assisted method and structurally characterized by routine techniques. Compound VMo12V2 represents the first example of one dimensional inorganic chain based on the bivanadium-capped saturated Keggin POMs, which is very stable in solution and air at the room temperature. Furthermore, compound VMo12V2 modified carbon-paste electrode (VMo12V2-CPE) displays the good electrocatalytic activity toward the reduction of bromate, in which the catalytic activity mainly depends on the six-electron-reduced species of Mo.

In recent years, China’s high-speed railway construction has developed rapidly, playing an extremely important role in the exchange of elements between cities and supporting the operation of the national urban system. The Yangtze River Delta region is one of the most advanced and balanced regions in China. With the rapid development of China’s high-speed railway construction, its regional spatial structure supported by the high-speed railway network has also undergone a series of changes. Based on the data of high-speed trains in the Yangtze River Delta region collected from the official website of the Ministry of Railways, the OD connection matrix between cities in the Yangtze River Delta was constructed, using some indexes such as network correlation degree, network density, central degree, to describe the characteristics of the city network in this region. The results show that, firstly, under the lead of Shanghai, the core corridor in the Yangtze River Delta region has been further strengthened. Secondly, as an important network hub in this region, the regional network status of Nanjing even exceeds that of Shanghai, and cities such as Hangzhou and Hefei also have the function of organizing sub-regional traffic. What is more, under the influence of the high-speed railway, the reach range of the metropolitan area has been greatly improved. A case comparison with the Ring-Bohai and Guangdong-Guangxi area showed that the Yangtze River Delta area is the most balanced among those three. Finally, some prospects for the future development of the Yangtze River Delta are discussed in this paper. Abstrak. Dalam beberapa tahun terakhir, pembangunan jaringab kereta api berkecepatan tinggi di Cina telah berkembang pesat, memainkan peran yang sangat penting dalam pertukaran elemen antara kota dan kota, dan mendukung sistem perkotaan nasional. Wilayah delta sungai Yangtze adalah salah satu daerah yang paling maju dan seimbang di Cina. Dengan perkembangan pesat pembangunan jaringan kereta api berkecepatan tinggi Cina, struktur tata ruang regionalnya yang didukung oleh jaringan kereta api berkecepatan tinggi juga telah mengalami serangkaian perubahan. Berdasarkan data kereta api berkecepatan tinggi di daerah delta sungai Yangtze yang dikumpulkan dari situs resmi kementerian perkeretaapian, dibangun matriks sambungan OD antara kota-kota di delta Sungai Yangtze dengan menggunakan beberapa indeks seperti tingkat korelasi jaringan, kepadatan jaringan, tingkat pemusatan, untuk menggambarkan karakteristik jaringan kota di wilayah ini. Hasilnya menunjukkan bahwa, pertama, di bawah pimpinan Shanghai, koridor inti di wilayah delta Sungai Yangtze telah diperkuat lebih lanjut. Kedua, sebagai hub jaringan penting di wilayah ini, status jaringan regional Nanjing bahkan melebihi Shanghai, dan kota-kota seperti Hangzhou dan Hefei juga memiliki fungsi mengatur lalu lintas sub-regional. Terlebih lagi, dipengaruhi kereta api berkecepatan tinggi, jangkauan area metropolitan telah sangat ditingkatkan. Perbandingan kasus dengan daerah Ring-Bohai dan Guangdong-Guangxi juga menunjukkan bahwa daerah delta Sungai Yangtze adalah yang paling seimbang di antara ketiga wilayah tersebut. Akhirnya, beberapa diskusi dan prospek tentang perkembangan masa depan delta sungai Yangtze disampaikan dalam makalah ini. Kata Kunci. Delta sungai Yangtze, kereta api berkecepatan tinggi, jaringan kota. Kata Kunci. Delta sungai Yangtze, kereta api berkecepatan tinggi, jaringan kota.

In this study, tensile testing of samples made of 316LN stainless steel was carried out at 1100 °C by using a Gleeble-1500D testing machine. By analyzing the effects of strain on the fracture behavior of 316LN samples in terms of the microstructural development of the heat-affected zone during the stretching process, it can be concluded that the formation of cracks in 316LN includes the nucleation, growth, and aggregation of microscopic cavities during the stretching process under high temperature. It was determined that the formation of cracks was accompanied by recrystallization. The higher the strain, the greater the recrystallization and the easier it is to crack the sample. It was also found that stress triaxiality plays an important role in the prediction of the destruction of the material.