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An additive manufacturing technology was used to produce anode foils with different polystyrene microsphere (PSM). The effect of PSM addition in the range of 0–20 vol% on the specific capacitance and bending strength of the anode foils was investigated. Scanning electron microscopy analysis confirms the presence of pores in the anode foils, which is attributed to the addition of PSM. The porosity and pore diameter of the anode foils increase with increasing PSM content, resulting in an initial increase and then a decrease in specific capacitance, as well as a gradual increase in bending strength. At a PSM addition of 12.5 vol%, the anode foils exhibit a high specific capacitance of 0.927 μF/cm2 and a bending strength of over 120 times greater, meeting the specific capacitance and bending strength requirements for anode foils in aluminum electrolytic capacitors. These findings suggest that incorporating PSM into anode foils is an effective method for adjusting their specific capacitance and bending strength.

ObjectiveTo develop a contrast-enhanced computed tomography (CECT) based radiomics model using machine learning method and assess its ability of preoperative prediction for the early recurrence of hepatocellular carcinoma (HCC).MethodsA total of 297 patients confirmed with HCC were assigned to the training dataset and test dataset based on the 8:2 ratio, and the follow-up period of the patients was from May 2012 to July 2017. The lesion sites were manually segmented using ITK-SNAP, and the pyradiomics platform was applied to extract radiomic features. We established the machine learning model to predict the early recurrence of HCC. The accuracy, AUC, standard deviation, specificity, and sensitivity were applied to evaluate the model performance.Results1,688 features were extracted from the arterial phase and venous phase images, respectively. When arterial phase and venous phase images were employed correlated with clinical factors to train a prediction model, it achieved the best performance (AUC with 95% CI 0.8300(0.7560-0.9040), sensitivity 89.45%, specificity 79.07%, accuracy 82.67%, p value 0.0064).ConclusionThe CECT-based radiomics may be helpful to non-invasively reveal the potential connection between CECT images and early recurrence of HCC. The combination of radiomics and clinical factors could boost model performance.

[Introduction] Monopile foundation is currently the most widely used support structure for offshore wind farms. For offshore wind farms in the medium water depth area such as Dafeng, Binhai and Sheyang in China, the design waves are very close to the wave breaking limit. Compared with the traveling wave, the focused waves can form an impact force on the pile column in a short time, which is larger than the conventional wave force, and undermines the operational performance and fatigue life of the offshore wind turbines. [Method] In this paper, NREL 5 MW monopile wind turbine model tests were carried out to investigate the hydrodynamic response of large offshore wind turbines to highly nonlinear waves and other harsh waves in combination with the marine environmental conditions of China's eastern coastal wind farms, focusing on exploring the test techniques for monopile wind turbines, and the mechanism of interaction between focused waves and monopiles under the action of focused waves. [Result] The results show that, the horizontal wave force on the pile foundation, which is significantly transient, will suddenly increase when the focused waves act on the monopile foundation, and receive the reverse impact force at the trough of focused wave fluctuation. [Conclusion] The results are of high theoretical value and have engineering prospect for the safe operation of monopile foundation.

In view of the detection requirements of pipeline internal and external surface defects and pipeline special regular structure detection, based on the magnetic shielding effect inside and outside the pipeline, the principle of magnetic field refraction at the interface between the pipe wall and air, and the principle of the magnetic field concentration on the pipe surface and the gap, this article focuses on the natural environment (geomagnetic background). The magnetic field distribution inside and outside the pipeline has been theoretically analyzed. After that, the finite element simulation software is used to model the finite length pipeline, and the internal and external magnetic fields are simulated and researched in combination with the finite element method. Finally, the tunnel magneto resistance (TMR) magnetic sensor is used to collect and process the internal magnetic field of the actual pipeline model, which verifies the correctness of the theoretical analysis. This paper analyzes the magnetic field inside and outside the pipeline by means of principle deduction, finite element simulation, and sensor measurement. The analysis results show that the distribution of the magnetic field in the pipeline under the excitation of the geomagnetic field has a very obvious regularity, which can meet the needs of pipeline defect detection. In addition, because the pipelines of different structures have different magnetic field distribution laws, they can also be used for the detection and analysis of pipelines with special structures.

The plant parasitic nematode, Aphelenchoides besseyi, is a serious pest causing severe damage to various crop plants and vegetables. The Bacillus thuringiensis (Bt) strains, GBAC46 and NMTD81, and the biological strain, FZB42, showed higher nematicidal activity against A. besseyi, by up to 88.80, 82.65, and 75.87%, respectively, in a 96-well plate experiment. We screened the whole genomes of the selected strains by protein-nucleic acid alignment. It was found that the Bt strain GBAC46 showed three novel crystal proteins, namely, Cry31Aa, Cry73Aa, and Cry40ORF, which likely provide for the safe control of nematodes. The Cry31Aa protein was composed of 802 amino acids with a molecular weight of 90.257 kDa and contained a conserved delta-endotoxin insecticidal domain. The Cry31Aa exhibited significant nematicidal activity against A. besseyi with a lethal concentration (LC50) value of 131.80 μg/mL. Furthermore, the results of in vitro experiments (i.e., rhodamine and propidium iodide (PI) experiments) revealed that the Cry31Aa protein was taken up by A. besseyi, which caused damage to the nematode’s intestinal cell membrane, indicating that the Cry31Aa produced a pore-formation toxin. In pot experiments, the selected strains GBAC46, NMTD81, and FZB42 significantly reduced the lesions on leaves by up to 33.56%, 45.66, and 30.34% and also enhanced physiological growth parameters such as root length (65.10, 50.65, and 55.60%), shoot length (68.10, 55.60, and 59.45%), and plant fresh weight (60.71, 56.45, and 55.65%), respectively. The number of nematodes obtained from the plants treated with the selected strains (i.e., GBAC46, NMTD81, and FZB42) and A. besseyi was significantly reduced, with 0.56, 0.83., 1.11, and 5.04 seedling mL−1 nematodes were achieved, respectively. Moreover, the qRT-PCR analysis showed that the defense-related genes were upregulated, and the activity of hydrogen peroxide (H2O2) increased while malondialdehyde (MDA) decreased in rice leaves compared to the control. Therefore, it was concluded that the Bt strains GBAC46 and NMTD81 can promote rice growth, induce high expression of rice defense-related genes, and activate systemic resistance in rice. More importantly, the application of the novel Cry31Aa protein has high potential for the efficient and safe prevention and green control of plant parasitic nematodes.

Tension leg platform (TLP) is a cost-effective and high-performance support structure for floating offshore wind turbine (FOWT) because of its small responses in heave, pitch, and roll with the constraint of the tendons. China, as the largest market of offshore wind energy, has shown a demand for developing reliable, viable floating platform support structures, especially aiming at the intermediate water depth. The present paper described a newly proposed 10-MW Braceless-TLP FOWT designed for a moderate water depth of 60 m. The numerical simulations of the FOWT are carried out using the coupled aero-hydro-servo-elastic-mooring calculation tool FAST. The measured wind and wave data of the target site close to the Fujian Province of China were used to evaluate the performance of the FOWT under the 100-, 50-, 5-, and 2-year-return stochastic weather conditions. The natural periods of the platform in surge, sway, heave, pitch, roll, and yaw were found to be within the range recommended by the design standard DNV-RP-0286 Coupled Analysis of Floating Wind Turbines. The largest surge of the water depth ratio among all the load cases was 15%, which was smaller than the admissible ratio of 23%. The tower top displacements remained between −1 m and 1 m, which were at a similar order to those of a 10-MW monopile-supported offshore wind turbine. The six tendons remained tensioned during the simulation, even under the operational and extreme (parked) environmental conditions. The Braceless-TLP FOWT showed an overall satisfying performance in terms of the structural stability and illustrates the feasibility of this type of FOWT at such a moderate water depth.

ABSTRACT: Cardiovascular diseases are the most frequent and costly complication of diabetes. Many previous studies showed that ATP-sensitive potassium channels (KATP) and inward rectifier potassium channels (Kir) play important regulatory roles in functions of cardiovascular tissues. Its still not very clear how these potassium channels are involved in cardiovascular complications of diabetes. We used the streptozotocin (STZ)-induced diabetic rats model to study the expressions of KATP and Kir channel subtypes in diabetic cardiovascular tissues. The mRNA expression levels of Kir2.1, Kir3.1, Kir6.1, Kir6.2, and sulfonylurea receptor (SUR) 2A and 2B subunits in heart and aortal smooth muscles were determined by the reverse-transcription polymerase chain reaction. The results showed that in comparison with the control rats, mRNA expression of SUR 2A was reduced significantly in the diabetic heart (SUR 2A/GAPDH, 1.04 ± 0.16 vs 0.38 ± 0.09, P

Pot and field experiments were conducted to study the effects of mulching with straw of cadmium (Cd) tolerant plants (Ranunculus sieboldii, Mazus japonicus, Clinopodium confine and Plantago asiatica) on growth and Cd accumulation of Galinsoga parviflora in Cd-contaminated soil. In the pot experiment, mulching with M. japonicus straw increased the root biomass, stem biomass, leaf biomass, shoot biomass, plant height and activities of antioxidant enzymes (superoxide dismutase, peroxidase and catalase) of G. parviflora compared with the control, whereas mulching with straws of R. sieboldii, C. confine and P. asiatica decreased these parameters. Straws of the four Cd-tolerant plants increased the Cd content in roots of G. parviflora compared with the control. However, only straws of M. japonicus and P. asiatica increased the Cd content in shoots of G. parviflora, reduced the soil pH, and increased the soil exchangeable Cd concentration. Straw of M. japonicus increased the amount of Cd extraction in stems, leaves and shoots of G. parviflora by 21.11%, 29.43% and 24.22%, respectively, compared with the control, whereas straws of the other three Cd-tolerant plants decreased these parameters. In the field experiment, the M. japonicus straw also increased shoot biomass, Cd content in shoots, and amount of Cd extraction in shoots of G. parviflora compared with the control. Therefore, straw of M. japonicus can be used to improve the Cd extraction ability of G. parviflora from Cd-contaminated soil.

An original two-step organocatalytic synthesis of optically active glutarimides from 2- oxocyclobutane carboxamides is described featuring an isothiourea-catalyzed two-atom ring-expansive rearrangement. [ABSTRACT FROM AUTHOR]

It was observed that the stable and commercially available N-heterocyclic carbene (NHC) 1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene, the so-called IDipp, catalyzes hydrogen/deuterium exchange reactions between pseudoacids and chloroform-d1, while the analogous saturated NHC 1,3-bis(2,4,6-trimethylphenyl)imidazolin-2-ylidene, the so-called SIMes, is inefficient for the same transformation. Experimental and computational DFT studies allowed these differences of reactivity to be attributed to the relative stability of the corresponding azolium-trichloromethyl anion ion pairs: in the former case, the complex evolves toward dissociation of the ions to produce an aromatic azolium cation and a basic trichloromethyl anion, while in the latter case, it evolves by ion recombination to give the product of formal carbene C-H insertion into the C-H bond of chloroform. These results provide a rationale for some early intuitions and observations of Wanzlick, Arduengo, and others on the reactivity of NHCs with chloroform as well as a simple organocatalytic method for the deuteration of pseudoacids (pKa,DMSO = 14-19) with chloroform-d1. [ABSTRACT FROM AUTHOR]

Transient outward K+ currents are particularly important for the regulation of membrane excitability of neurons and repolarization of action potentials in cardiac myocytes. These currents are modulated by PKC (protein kinase C) activation, and the K+- channel subunit Kv4.2 is a major contributor to these currents. Furthermore, the current recorded from Kv4.2 channels expressed in oocytes is reduced by PKC activation. The mechanism underlying PKC regulation of Kv4.2 currents is unknown. In the present study, we determined that PKC directly phosphorylates the Kv4.2 channel protein. In vitro phosphorylation of the intracellular N- and C-termini of Kv4.2 GST (glutathione transferase) tagged fusion protein revealed that the C-terminal of Kv4.2 was phosphorylated by PKC, whereas the N-terminal was not. Amino acid mapping and site-directed mutagenesis revealed that the phosphorylated residues on the Kv4.2 C-terminal were Ser447 and Ser537. A phospho-site-specific antibody showed that phosphorylation at the Ser537 site was increased in the hippocampus in response to PKC activation. Surface biotinylation experiments revealed that mutation to alanine of both Ser447 and Ser537 in order to block phosphorylation at both of the PKC sites increased surface expression compared with wild-type Kv4.2. Electrophysiological recordings of the wild-type and both the alanine and aspartate mutant Kv4.2 channels expressed with KChIP3 (Kv4 channel-interacting protein 3) revealed no significant difference in the half-activation or half-inactivation voltage of the channel. Interestingly, Ser537 lies within a possible ERK (extracellular-signal-regulated kinase)/MAPK (mitogen-activated protein kinase) recognition (docking) domain in the Kv4.2 C-terminal sequence. We found that phosphorylation of Kv4.2 by PKC enhanced ERK phosphorylation of the channel in vitro. These findings suggest the possibility that Kv4.2 is a locus for PKC and ERK cross-talk. [ABSTRACT FROM AUTHOR]

We evaluated a role for the nuclear factor-kappa B (NF-κB) pathway in the regulation of seizure susceptibility and transcriptional activation during prolonged, continuous seizures (status epilepticus). Using two functionally distinct NF-κB inhibitors we observed a decrease in latency to onset of kainate-induced seizures and status epilepticus. To assess NF-κB transcriptional activation, we evaluated inhibitor kappa B alpha ( IκBα) and brain-derived neurotrophic factor ( bdnf) gene targets. Inhibition of the NF-κB signaling pathway significantly attenuated the increases in IκBα and bdnf mRNA levels that occurred during prolonged seizure activity, suggesting that the NF-κB pathway was involved in the up-regulation of these transcripts during status epilepticus. DNA-binding studies and chromatin immunoprecipitation assays using hippocampal extracts from animals with status epilepticus revealed that NF-κB subunits were associated with the candidate κB-binding elements within promoter 1 of the bdnf gene. The pattern of association was different for the p50 and p65 subunits supporting complex NF-κB modifications within promoter 1. In summary, our findings provide additional insights into the role of NF-κB transcriptional regulation in hippocampus following status epilepticus and suggest that NF-κB pathway activation contributes to seizure susceptibility. [ABSTRACT FROM AUTHOR]

Small conductance, Ca2+-activated voltage-independent potassium channels (SK channels) are widely expressed in diverse tissues; however, little is known about the molecular regulation of SK channel subunits. Direct alteration of ion channel subunits by kinases is a candidate mechanism for functional modulation of these channels. We find that activation of cyclic AMP-dependent protein kinase (PKA) with forskolin (50 µM) causes a dramatic decrease in surface localization of the SK2 channel subunit expressed in COS7 cells due to direct phosphorylation of the SK2 channel subunit. PKA phosphorylation studies using the intracellular domains of the SK2 channel subunit expressed as glutathione S-transferase fusion protein constructs showed that both the amino-terminal and carboxyl- terminal regions are PKA substrates in vitro. Mutational analysis identified a single PKA phosphorylation site within the amino-terminal of the SK2 subunit at serine 136. Mutagenesis and mass spectrometry studies identified four PKA phosphorylation sites: Ser465 (minor site) and three amino acid residues Ser568, Ser569, and Ser570 (major sites) within the carboxyl-terminal region. A mutated SK2 channel subunit, with the three contiguous serines mutated to alanines to block phosphorylation at these sites, shows no decrease in surface expression after PKA stimulation. Thus, our findings suggest that PKA phosphorylation of these three sites is necessary for PKA-mediated reorganization of SK2 surface expression. [ABSTRACT FROM AUTHOR]