This paper proposes and improves the traditional K-means algorithm, utilizes the HC-Kmeans algorithm to deeply analyze the marketing status quo of the M e-commerce platform, and constructs the ...overall framework of precision marketing based on big data technology. The RFM model is used to measure customer value and segment customer behavior. Formulate marketing strategies that correspond to the consumption habits and preferences of different categories of users. The data from 40 consecutive days of observation is used to verify the precision marketing effect of the A/B testing method, and the final results show a good improvement in the click rate, order rate, payment rate, and order amount. During the Double Twelve Shopping Festival, compared with the traditional mode, the payment amount of M Company’s product recommendation increased by 64,604 yuan, and the order increased by 301 units, so the implementation of the precision marketing strategy was effective.
Therapeutic glycoproteins have occupied an extremely important position in the market of biopharmaceuticals. N-Glycosylation of protein drugs facilitates them to maintain optimal conformations and ...affect their structural stabilities, serum half-lives and biological efficiencies. Thus homogeneous N-glycoproteins with defined N-glycans are essential in their application in clinic therapeutics. However, there still remain several obstacles to acquire homogeneous N-glycans, such as the high production costs induced by the universal utilization of mammalian cell expression systems, the non-humanized N-glycan structures and the N-glycosylation microheterogeneities between batches.
In this study, we constructed a Pichia pastoris (Komagataella phaffii) expression system producing truncated N-GlcNAc-modified recombinant proteins through introducing an ENGase isoform (Endo-T) which possesses powerful hydrolytic activities towards high-mannose type N-glycans. The results showed that the location of Endo-T in different subcellular fractions, such as Endoplasmic reticulum (ER), Golgi or cell membrane, affected their hydrolytic efficiencies. When the Endo-T was expressed in Golgi, the secreted IgG1-Fc region was efficiently produced with almost completely truncated N-glycans and the N-GlcNAc modification on the glycosite Asn
was confirmed via Mass Spectrometry.
This strategy develops a simple glycoengineered yeast expression system to produce N-GlcNAc modified proteins, which could be further extended to different N-glycan structures. This system would provide a prospective platform for mass production of increasing novel glycoprotein drugs.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
Solid contamination existing as solid particles in power fluid transmission systems may lead to transmission performance reduction, system failures, and component damage. The hydraulic reservoir will ...deposit the contamination and store hydraulic fluid. To investigate its purification ability for solid contamination, experiments and simulations for the motion and deposition status of the typical hydraulic system particles are carried out to reveal the interaction of particles and fluid in hydraulic water reservoirs. The results show that the CFD-DEM coupling method could predict the accurate deposition position of iron particles and sand particles when ignoring the small-scale turbulence effect in the flow field. Besides, the particle motion traces and deposition patterns in the reservoir illustrate that the flow development on the bottom surface results in the particles turning, and particles tend to settle in the low flow energy position. The motion of particles is also linked to particles Stokes number, and the same-size sand particles are easily driven by the fluid. The contribution of this paper could provide a guide for predicting the particle motion and deposition pattern in the hydraulic reservoir.
Piezoceramics and related devices are naturally fragile. Here we have produced piezoelectric composites of Ni-particle-dispersed Li-doped (K,Na)NbO3 (LKNN/Ni), and used these composites to make ...actuators with functionally graded microstructure (FGM). The mechanical properties of the LKNN/Ni composites were greatly enhanced by the incorporation of Ni particles. An LKNN–20%Ni composite exhibited double the fracture toughness of the monolithic LKNN ceramic. An LKNN/Ni piezoelectric FGM actuator subjected to a large number of cycles of electrical loading still maintained acceptable driven performance. The enhancement of reliability in the LKNN/Ni composites and actuators is attributed to the uniformly dispersed Ni particles in the piezoceramic matrix. Deformation of these Ni particles absorbs the energy of crack propagation and thus greatly strengthens the composites and devices. These new FGMs contribute further to the reliability enhancement of piezoelectric actuators.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
An ice sheet on the water surface will affect the water-entry process dynamic characteristics. Therefore, studying the process of high-speed projectiles passing through the ice sheet and entering the ...water is of great strategic significance. Based on the coupled Eulerian–Lagrangian (CEL) method, this study verifies the accuracy of the numerical solution for the high-speed water entry problem of projectiles. The elastoplastic constitutive model is used to simulate the mechanical behavior of the sea ice. The numerical results are compared with the experimental data to verify the applicability of the material model to the high-speed collision problem. Herein, the conditions of no ice and ice sheet thicknesses of 0.2, 0.6, and 1.0 m are considered. During the high-speed water entry process of projectiles, the evolution of the cavity is analyzed and compared with or without ice. Furthermore, the influence of the ice sheet on the axial load characteristics of the structure is presented. Simultaneously, general conclusions are afforded by observing the formation and propagation of cracks for the three ice sheets with varying thicknesses.
•The dynamic characteristics of high-speed water-entry with the presence of ice sheet are investigated.•The crack propagation of ice sheet during the water entry process is analyzed.•The influence of ice thickness on the cavity evolution, structural response and load characteristics is evaluated.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ
The purpose of this study is to analyze the subsonic and transonic water entry of the axisymmetric body with compressibility effect considered. The water-entry processes of axisymmetric body are ...numerically investigated, with Tait state equation and energy equation used to describe the compressibility of the liquid. Reasonable agreement has been obtained between the numerical results and the experimental measurements of trajectory, velocity and acceleration. The cavity evolution and dynamic characteristics of subsonic cases are investigated for vertical and oblique water-entry. The results show that the maximum drag coefficient of the oblique water entry is lower, and it is affected by a large moment which causes pitch angle and trajectory inclination angle to change significantly. In the oblique transonic conditions, the effect of compressibility of the liquid on the dynamic flow characteristics is analyzed. On this basis, the influence of entry angle on the hydrodynamic characteristics is investigated. It is concluded that the water-entry angle has a more significant influence on the trajectory characteristics.
•Investigate the flow structure and dynamic characteristics of subsonic water-entry cases for vertical and oblique water-entry.•Analyze the effect of compressibility of the liquid on the dynamic flow characteristics of transonic water-entry cases.•Improve the understanding of the influence of entry angle on the hydrodynamic characteristics with compressibility considered.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ
•The multiphase flow during water entry of a spinning sphere with hydrophobic surface is studied by numerical method.•The Boundary Data Immersion Method (BDIM) modified by the wetting model is ...applied to the three dimensional simulation for the water entry problem.•The effect of spin rate on the splash and cavity evolution during water entry of the sphere is further investigated.•The trajectory, velocity, and acceleration of the sphere as well as the hydrodynamic forces it experiences are quantitatively analyzed.
The process of water entry is a complex and attractive field of research, since from more than a century ago there are wide applications in industry, nature science, bionics, and naval technology. The objective of this work is to investigate the cavity dynamics during water entry of a spinning sphere by numerical simulations. The algorithm of these simulations uses the Boundary Data Immersion Method (BDIM) to model the solid/fluid interactions, and the interface between the liquid and the gas is tracked by the volume-of-fluid (VOF) method. The uniform Cartesian-grid is used, and the effect of surface wettability is considered. The governing meta-equations for the full domain ensure the stable and accurate prediction on the pressure value on the solid boundary. Numerical results are validated with experiments, and good agreement between numerical and experimental results has been obtained for the transient cavity formation and the motion of the sphere. To further investigate the influence of the spin rate on the splash and cavity evolution and hydrodynamic characteristics, five different spin rates with a constant impact velocity are considered. Results reveal that the spin rate has significant influence on the cavity and splash asymmetry as well as the moment of pinch-off, while the depth of pinch-off is almost constant. The vortex structures show that both effects of rotation and shear play a role on the evolution of splash and cavity. The hydrodynamic forces fluctuate dramatically both at the moment of impact and the pinch off of the cavity. They gradually tend to be constant as the sphere descent with an open cavity.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
•A simultaneous sampling technique is applied to investigate air injection effects on two different cavitation shedding dynamics.•Air injection effects on unsteady cavity behaviors are observed.•Air ...injection effects on unsteady pressure fluctuation characteristics are clarified.
The objective of this paper is to investigate the effects of air injection on the characteristics of two different unsteady sheet/cloud cavitation shedding mechanisms, namely re-entrant flow mechanism and bubbly shock propagation mechanism, in the convergent-divergent channel. Experiments were conducted in the 10° divergent section with a ventilation slit near the throat, using a simultaneous sampling technique to synchronize the transient cavity behaviors with wall-pressure signals. Results are presented at a Reynolds number 9.33 × 105 and Froude number 10.24 for (1) under re-entrant flow mechanism (σ = 0.81) characterized by the intermittent shedding of small-scale cavities, and (2) under bubbly shock propagation mechanism (σ = 0.70) characterized by periodic large-scale cavity cloud shedding, with three non-dimensional air injection volumetric flow rates, namely 0, 1.135 × 10−3 and 2.270 × 10−3. The results show that air injection from the throat into the shear layer can significantly suppress cavitation induced unsteady pressure fluctuations. With the increasing of air flow rate, the size of the attached sheet cavity and the shedding cavity clusters grows larger, and the distance between the new attached sheet cavity and the shedding cavity cloud decreases, resulting in the cavitation region misty. The cavitation evolution tends to be stable, indicating the increase in the cavitation cycle, and the FFT analysis of the unsteady pressure fluctuations shows the decrease in dominant frequency. For the re-entrant flow mechanism condition, air injection rate at 1.135 × 10−3 will cause the transition from small-scale cavity clusters shedding to large-scale cavity cloud shedding, accompanying with pressure fluctuations increasing. With the air injection rate further increase, the pressure fluctuations decrease. Air injection can significantly reduce the unsteady pressure fluctuations spectral content in the frequency range of 1 kHz to 10 kHz. For the bubbly shock propagation mechanism condition, air injection can avoid the formation and propagation of the bubbly shock and suppress both the pressure peaks and pressure fluctuations. With the increase in the air injection rate, the unsteady pressure fluctuations are further suppressed. The unsteady pressure spectral content between 0.2 kHz and 10 kHz is effectively reduced.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Background
The protein tyrosine phosphatase delta (PTPRD) is a tumor suppressor, and its role in gastric cancer (GC) remains poorly understood.
Methods
The expressions of PTPRD were determined based ...on public data. In addition, the mRNA expressions of PTPRD in the GC samples, and the expressions of PTPRD in the GC cell lines including HGC27, SGC790, and BGC823, and gastric epithelial cell line GES-1 were determined by western blotting and quantitative real-time PCR. Furthermore, PTPRD siRNA was transfected into the HGC27 cell line, and then, cell proliferation, migration, and invasion were evaluated. The activity of signal transducer and activator of transcription 3 (STAT3) pathways in HGC27 cells transfected with PTPRD siRNA was determined by western blotting.
Results
PTPRD deletion was found in the GC patients, and this deletion was found to be correlated with poor prognosis in the GC patients. Expression of PTPRD was significantly downregulated in gastric carcinoma specimens and tumor cell lines when compared with those in normal controls. PTPRD also plays a key role in the GC cells proliferation, invasion, and migration. Silencing PTPRD expression by siRNA dramatically promoted GC cells proliferation, invasion, and migration. Mechanism study demonstrated that phosphorylation of STAT3 was inhibited by silencing PTPRD expression and the according changes including inhibition of cell migration and invasion were observed.
Conclusion
This study supports PTPRD as a tumor suppressor and could be served as a marker for prognostic of GC. Silencing PTPRD could be a potential therapeutic in GC.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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