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With the development of 5G communication technology and the rise of power semiconductors, the switching frequency of the circuit keeps increasing, which pushes for miniaturization of power modules and related components. Therefore, in this paper, a one-step molding technology was proposed for a DC/DC buck converter power module. We proposed a method of using Soft Magnetic Powder filled Epoxy (SMPE) adhesive as a molding material to encapsulate a power module, which is a DC/DC buck converter power module contains several passive components, 1 power inductor, and a high-efficiency switching regulator with two integrated N-channel MOSFETs. On the basis of Finite Element Method (FEM), models were firstly established with component level moldings and checked with actual module samples for calibration. Based on the calibrated model, inductors without component level molding were then simulated. SMPE with 4~7μm insulated carbonyl ferrous powder were prepared and measured the magnetic relative permeability. Such material was investigated to pot the whole power module as a one-step molding, instead of separate molding for the power inductor and the power module. After that, thermal analysis and inductance were calculated and compared.

Hematopoietic stem cells (HSCs)/progenitor cells (HPCs) are generated from hemogenic endothelial cells (HECs) during the endothelial-to-hematopoietic transition (EHT); however, the underlying mechanism remains poorly understood. Here, using an array of approaches, including CRSPR/Cas9 gene knockouts, RNA-Seq, ChIP-Seq, ATAC-Seq etc., we report that vitamin C (Vc) is essential in HPC generation during human pluripotent stem cell (hPSC) differentiation in defined culture conditions. Mechanistically, we found that the endothelial cells generated in the absence of Vc fail to undergo the EHT because of an apparent failure in opening up genomic loci essential for hematopoiesis. Under Vc deficiency, these loci exhibited abnormal accumulation of histone H3 trimethylation at Lys-27 (H3K27me3), a repressive histone modification that arose because of lower activities of demethylases that target H3K27me3. Consistently, deletion of the two H3K27me3 demethylases, Jumonji domain-containing 3 (JMJD3 or KDM6B) and histone demethylase UTX (UTX or KDM6A), impaired HPC generation even in the presence of Vc. Furthermore, we noted that Vc and jmjd3 are also important for HSC generation during zebrafish development. Together, our findings reveal an essential role for Vc in the EHT for hematopoiesis, and identify KDM6-mediated chromatin demethylation as an important regulatory mechanism in hematopoietic cell differentiation.

In this paper, a monitoring-statistic-based fault subspace decomposition and double decomposition (DD) reconstruction method is presented to deal with multivariable continuous slow-varying process fault prognosis. The new method assumed that fault is known and can be completely reconstructed. Then, the fault directions are determined by the monitoring-statistic-based fault subspace decomposition method. Finally, the DD reconstruction method and the vector autoregression (VAR) method are used to calculate and predict the magnitude degeneration process of corresponding fault directions. After that, online fault prognosis is realized. The experiments show the effectiveness of the developed method.

Autophagy, an evolutionarily conserved lysosomal degradation pathway, is known to regulate a variety of physiological and pathological processes. At present, the function and the precise mechanism of autophagy regulation in kidney and renal cells remain elusive. Here, we explored the role of ERK1 and ERK2 (referred as ERK1/2 hereafter) in autophagy regulation in renal cells in response to hypoglycemia. Glucose starvation potently and transiently activated ERK1/2 in renal cells, and this was concomitant with an increase in autophagic flux. Perturbing ERK1/2 activation by treatment with inhibitors of RAF or MEK1/2, via the expression of a dominant-negative mutant form of MEK1/2 or RAS, blocked hypoglycemia-mediated ERK1/2 activation and autophagy induction in renal cells. Glucose starvation also induced the accumulation of reactive oxygen species in renal cells, which was involved in the activation of the ERK1/2 cascade and the induction of autophagy in renal cells. Interestingly, ATG13 and FIP200, the members of the ULK1 complex, contain the ERK consensus phosphorylation sites, and glucose starvation induced an association between ATG13 or FIP200 and ERK1/2. Moreover, the expression of the phospho-defective mutants of ATG13 and FIP200 in renal cells blocked glucose starvation-induced autophagy and rendered cells more susceptible to hypoglycemia-induced cell death. However, the expression of the phospho-mimic mutants of ATG13 and FIP200 induced autophagy and protected renal cells from hypoglycemia-induced cell death. Taken together, our results demonstrate that hypoglycemia activates the ERK1/2 signaling to regulate ATG13 and FIP200, thereby stimulating autophagy to protect the renal cells from hypoglycemia-induced cell death.

Definitive hematopoiesis generates hematopoietic stem/progenitor cells (HSPCs) that give rise to all mature blood and immune cells, but remains poorly defined in human. Here, we resolve human hematopoietic populations at the earliest hematopoiesis stage by single-cell RNA-seq. We characterize the distinct molecular profiling between early primitive and definitive hematopoiesis in both human embryonic stem cell (hESC) differentiation and early embryonic development. We identify CD44 to specifically discriminate definitive hematopoiesis and generate definitive HSPCs from hESCs. The multipotency of hESCs-derived HSPCs for various blood and immune cells is validated by single-cell clonal assay. Strikingly, these hESCs-derived HSPCs give rise to blood and lymphoid lineages in vivo. Lastly, we characterize gene-expression dynamics in definitive and primitive hematopoiesis and reveal an unreported role of ROCK-inhibition in enhancing human definitive hematopoiesis. Our study provides a prospect for understanding human early hematopoiesis and a firm basis for generating blood and immune cells for clinical purposes.

Here we report a mechanism investigation on the ordered aggregation of particles at a diffusion limitation. A gel solution is employed to create a diffusion limitation for the synthesis of silver particles. Diamond-shaped silver particles are largely generated in an agar gel solution. The time dependent characterization of samples indicates that the diamond-shaped silver particles are built up by the aggregation of primary nanocrystals. A molecular simulation is conducted to reveal this aggregation process. Under diffusion limitation these tiny crystals tend to aggregate by sharing the high energy facets of (100), while the low energy facets of (111) is largely exposed, which results in an oriented aggregation, forming diamond-shaped particles. This formation mechanism is confirmed by following experiments via conducting the synthesis in different gel systems at different gel addition. The results of this paper indicate that the diffusion of building blocks plays an important role in the structure development of aggregates, which was underestimated previously.

Cesium (Cs) is a key promoter to improve the selectivity of Ag catalyst for ethylene epoxidation. However, there is still no consensus in the literature about the origin of enhanced ethylene oxide (EO) electivity by Cs-promoted Ag catalysts. In this paper, the role of Cs as a promoter for ethylene epoxidation on Ag catalyst is studied by both experiments conducted under industrially relevant conditions as well as density functional theory (DFT) calculations. Ag/α-Al 2 O 3 and Ag-Cs/α-Al 2 O 3 catalyst are prepared by excessive impregnation and evaluated for ethylene epoxidation to determine the mechanism of selectivity enhancement for Ag catalysts that contain Cs. With the optimal loading of Cs, Ag particles of uniform size are evenly distributed on the support and EO selectivity increases from approximately 72.5%–82.0% compared with the Ag/α-Al 2 O 3 . O 2 -TPD results indicate that Cs decreases the adsorption strength of oxygen on Ag and XPS analyses show that Cs shifts the Ag 3d 5/2 binding energy to facilitate the desorption of the EO precursor to form gas EO. DFT calculations demonstrate that Cs-promotor can weaken the adsorption of atomic oxygen. Electron density of atom oxygen absorbed on silver decreases with the addition of Cs on Ag(111) thereby enhancing the electrophilic attack by atomic oxygen at the electron-rich C C bond of C 2 H 4 . Therefore, Cs lowers the activation energy for the formation of the oxometallacycle (OMC) and EO, while increasing the barrier for acetaldehyde (AA) formation, thereby leading to higher EO selectivity.

Rhenium is an important promotor for silver catalyst, and very little work has been focused on the effect of rhenium loading sequence on the selectivity of ethylene oxide. Re was introduced to the Ag–Cs catalyst supported on α-Al2O3 in three different ways: co-impregnation (Ag–Cs–Re), step-impregnation with Re loaded first (Re/Ag–Cs), and step-impregnation with Re loaded last (Ag–Cs/Re). The selectivity of Re/Ag–Cs and Ag–Cs–Re are about 20% higher than that of Ag–Cs/Re, which indicates that the performance of the catalyst is influenced by the synergistic effect of Re and Cs. Rhenium oxides with the valence of + 4 to + 7 are distributed around the Ag particles. The binding energy of Re is increased by about 0.2 eV by the addition of Cs in the Ag–Cs–Re catalyst, and the presence of Re with high valence around Ag will cause the electrons to shift toward the Re atom, facilitating the formation of weakly adsorbed oxygen and improving the selectivity of the Ag–Cs catalyst. On the Ag–Cs/Re catalyst, Re is mostly loaded on the external Ag surface, and the binding energies of Ag 3d5/2 and Cs 3d5/2 increase by 0.2 and 0.4 eV, respectively, from the Ag–Cs/Re catalyst to the Ag–Cs–Re and Re/Ag–Cs catalysts. The higher binding energy of Ag leads to the stronger oxygen adsorption, which contributes to the complete oxidation reaction, thereby resulting in lower selectivity.

The diesel engine is the core power equipment of ships, so keeping it in good working condition is vital for maintaining the overall efficiency of sea transportation. Generally speaking, the principal component analysis (PCA) based fault detection methods are highly depend on the unlabeled information of training data, that is means, the information contained in labeled data is largely ignored. However, the diesel engine working process is always accompanied with small amount of faulty samples, which may seriously affect the performance of the PCA model when the faulty samples are included for modeling. Besides, even though there are enough faulty samples for modelling, labeling these samples is also time-consuming and costly. In this paper, a semi-supervised PCA (SSPCA) is proposed and applied to diesel engine fault diagnosis instead of unsupervised learning, which incorporates both the labeled and unlabeled samples and gains enhanced fault diagnosis performance regarding marine diesel engine. The methodology presented is evaluated in the real-world diesel engine working process, the experimental results indicate good robustness to false alarms and certain practical significance towards the fault diagnosis of engineering object.

Bearings play an important role in mechanical systems, and it is of great significance to monitor the health status of the bearing in real time for ensuring long-term stable operation of mechanical system. This paper proposes a new reconstruction-based fault prognosis method to process the time domain and frequency domain characteristics of vibration signals. Firstly, the principal component analysis (PCA) model is established to detect the fault factors in current measurement data. And then, the fault directions are selected according to its fault correlation and the robustness of the corresponding fault magnitude evolution process. Finally, the vector autocorrelation (VAR) model is used to predict the fault degradation process to achieve complete fault prognosis. The effectiveness of the developed method is validated by PRONOSTIA data.

Objectives: To compare the sensitivity of identification of penile plaques in the erect and flaccid penises by ultrasound in patients with Peyronie’s disease (PD). Materials and Methods: A total of 75 PD patients were screened by palpation and ultrasonography for penile lesions in both flaccid and erect penises induced by prostaglandin E1 (PG-1) injection. Results: A total of 138 lesions were identified by ultrasound in the erect penises induced by injection of PG-1. However, only 74.6% of the lesions (103) were detectable by the palpation of the flaccid penises, and 84.1% (116) by ultrasound of the flaccid penises. The ultrasound confirmed 99 of the palpated lesions in the flaccid penises. The detection rate of lesions in drug-induced erect penises by ultrasound was significantly higher than those in the flaccid penises by the ultrasound（P < 0.01）or palpation （P < 0.0005） The type of penile lesions identified by ultrasonography included tunical thickening, calcifications, septal fibrosis, and intracavernosal fibrosis. The ratios of these lesions confirmed by ultrasound were 52.6%, 33.6%, 6.0%, and 7.8%, respectively, in the flaccid penises, and 55.8%, 28.3%, 8.7%, and 7.2%, respectively, in the erect penises. Conclusion: Drug-induced erection can be used in suspicious PD patients when penile lesion is not identified by palpation or ultrasound in the flaccid penis.

The goal of this work was to characterize the blood flow in cavernosal-spongiosal communications (CSCs) in patients with erectile dysfunction using color Doppler ultrasound. Peak systolic velocity was measured in the CSCs, cavernosal artery and urethral artery in 72 erectile dysfunction patients of the Han ethnic group in southern China. Blood in the CSCs was observed to flow from the cavernosal artery to the urethral artery in all except 5 patients with arteriogenic insufficiency whose blood flow was bidirectional. Peak systolic velocity in erectile dysfunction patients with normal vascular function or veno-occlusive dysfunction was significantly lower in the CSCs than in the cavernosal artery (p0.01), but significantly higher than in the urethral artery (p0.05). Peak systolic velocities in CSCs in patients with arteriogenic insufficiency were significantly lower than those in the cavernosal (p0.01) and urethral (p0.01) arteries. The direction of blood flow in the CSCs is determined by the pressure gradient between the cavernosal and urethral arteries.

Web service is a popular solution to integrate components when building a software system, or to allow communication between a system and third-party users, providing a flexible and reusable mechanism to access its functionalities. Various web service based systems are prevailing in health service provision. We propose a framework of construction, searching and protection of typed health resources in terms of data, information and knowledge through a hierarchy consisting of Data Graph, Information Graph and Knowledge Graph. We use cases to illustrate the mechanism of the framework.

The absorption and fluorescence measurements have been used to study the interactions between cationic gemini surfactant micelles of alkanediyl-α,ω-bis(dodecyldimethylammonium bromide) (C 12 C s C 12 Br 2 , where s = 2, 3, 4, 6, and 12, indicating the number of carbons in the spacer) with trianionic curcumin (Cur 3− ) at pH 13. With increasing spacer length of gemini surfactant, the maximum intensities of absorption and fluorescence peaks of Cur 3− give the highest values at s = 6, reflecting that the spacer length of gemini surfactant significantly regulates the electrostatic attractive interactions between C 12 C s C 12 Br 2 micelles and Cur 3− . The maximum fluorescence intensity of Cur 3− in C 12 C 6 C 12 Br 2 micelle shows increasing tendency at 0–100 mM sodium bromide concentration ( C NaBr ), but decreases above C NaBr = 120 mM. This result is explained in terms of the enhanced electrostatic attraction of Cur 3− with C 12 C 6 C 12 Br 2 micelle at low salt concentrations and the reduced electrostatic attraction at high salt amounts. The determined p K a1 values of curcumin in C 12 C s C 12 Br 2 micelles support the strongest electrostatic association between C 12 C 6 C 12 Br 2 micelle and anionic Cur − . The interaction mechanisms of C 12 C s C 12 Br 2 micelles with Cur 3− have been further proposed at s = 2–4, s = 6, and s = 12, which is related to the matching of the positive charges in C 12 C s C 12 Br 2 micelles to the negative charges in Cur 3− .

This work studied the influences of formation of BSA/ι-carrageenan complexes on the binding, stability, and antioxidant activity of curcumin. In the presence of BSA and ι-carrageenan, curcumin gives higher intensities of absorption and fluorescence than free curcumin and curcumin only combined with BSA. The added ι-carrageenan is observed to promote curcumin for quenching the instrinsic fluorescence of BSA. These results are explained in terms of the formation of BSA/ι-carrageenan complexes, which help to stabilize the folded structure of BSA for providing curcumin with a more hydrophobic microenvironment. The small difference in anisotropy values of curcumin with BSA alone and of BSA/ι-carrageenan complexes suggests that ι-carrageenan acts as outer stretch conformation in BSA/ι-carrageenan complexes but does not directly disturb the hydrophobic pockets inside BSA, where curcumin is hydrophobically located. The determined values of the binding constant are higher for curcumin with BSA/ι-carrageenan complexes than with BSA alone. Moreover, BSA/ι-carrageenan complexes are found to be superior to single BSA for enhancing the stability and DPPH radical-scavenging ability of curcumin.

The suppression of antenna direct coupled wave and medium surface wave is an very important step in the signal processing of the shallow surface penetrating imaging radar. For shallow buried targets, due to its buried depth is less than the depth resolution, the traditional clutter inhibition method based on the mean cancellation and distance gating is not applicable. In addition, in order to improve the scanning efficiency, array antennas are usually used to realize the simultaneous sampling to multiple spatial position echoes. The discordance of amplitude and phase between the multi-channel of the antenna array also makes the clutter suppression effect of the mean cancellation algorithm not ideal. In this paper, an adaptive suppression method for array antenna based on the maximum entropy gradient is proposed. Experimental results prove that this method can effectively repress the two kinds of clutter and improve the image quality effectively. The processing results using measured data prove this method effective in clutter suppression.

Radar High Resolution Range Profile (HRRP) represents the radial distribution of target scattering centers on radar line of sight, which infers something about target structure signatures. In this paper, the method of HRRP target recognition based on Gradient Boosting Decision Tree (GBDT) is proposed and the method how to choose model parameters is investigated. The experimental results from measurement data have shown that GBDT can achieve better recognition results and high calculation efficiency than SVM and Naive Bayes classifier.

This article firstly analyses the principles and characteristics generated by CAPP in view of elaboration on the main mode of IP financing security. Secondly, it reveals the patterns and contents of IP financing security based on CAPP from market-oriented security operation, systematic process control and proactive risk management. Finally, according to the feasibility and superiority of CAPP in the IP financing security and the practical situation of IP financing security for SMEs in China, it puts forward the significance and development of IP financing security based on CAPP.