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Sodium alginate exhibits poor stability when applied as a single gel network, which undermines its efficacy in probiotic encapsulation and protection. This study aimed to incorporate alginate (Alg) with cyclodextrin to prepare a supramolecular hydrogel to enhance the encapsulation and viability of probiotics. Specifically, l-tryptophan (L-Trp) and Sulfobutylether-β-cyclodextrin (SBE-β-CD) were employed to self-assemble into an inclusion complex (IC). Alg/Trp-SBE-β-CD hydrogels were formed using calcium ion-mediated cross-linking and IC addition. Experimental data revealed that the Alg/Trp-SBE-β-CD gels with 1 wt% CaCl 2 exhibited good overall performance. The hydrogels significantly improved the stability and release properties of loaded Bifidobacterium animalis F1-7 compared to single Alg gels. Notably, the survival rate was 95.5% after 2 h in simulated gastric fluid (SGF), and the release rate reached 97.7% after continuous release in simulated intestinal fluid (SIF) for 6 h. Probiotic viable counts were maintained at 7–8 log CFU/g after 4 weeks of storage. This study indicates that a hybrid wall material of Alg and Trp-SBE-β-CD IC can enhance the stability and controlled release of bioactive compounds including synbiotics (prebiotics + probiotic preparations). [Display omitted] • L-Tryptophan and SBE-β-CD formed inclusion complex (IC) by host-guest interactions. • A super supramolecular hydrogel incorporating alginate (Alg) with IC was prepared. • Alg/Trp-SBE-β-CD hydrogels enhanced encapsulation and in vitro viability of probiotics. • Alg/Trp-SBE-β-CD improved probiotics release compared to a single Alg network. • IC added enhanced the antioxidant capacity of probiotics loaded hydrogel. [ABSTRACT FROM AUTHOR]

Catalytic wet air oxidation (CWAO) is a promising process for degrading phenol in wastewater to CO 2 and H 2 O. To achieve an active and stable Pt catalyst working at lower temperature, efficient catalysts are here developed by building a Pt-M (M=Pb, Cu) alloy structure where Pt is mainly in the form of Pt0 while M is mainly in the form of M2+. Firstly, carbon supported Pt-Pb/XC-72R and Pt-Pb/EC-300 catalysts are prepared for CWAO of phenol wastewater. It is found that Pt-Pb/XC-72R is highly active and stable for CWAO of phenol even at 100 °C. The initial TOC conversion is 91.1% and can be maintained higher than 75% in five consecutive cycles. Contrarily, Pt-Pb/EC-300 rapidly deactivates and TOC conversion decreased from 91.2% to 47.1% after five cycles. The characterization results indicate that two Pt-Pb alloy catalysts contained comparably high Pt0 concentration, which is responsible for the high activity. However, the Pb2+ concentration of Pt-Pb/XC-72R is much higher than that of Pt-Pb/EC-300, and higher Pb2+ concentration favors surface oxidation and keeps Pt0 from being oxidized during CWAO process, thus enhancing stability. For Pt-Pb/EC-300, both Pt0 and Pb0 are oxidized during the reaction, resulting in deactivation. To avoid using Pb in environmental considerations, the Pt-Pb is then replaced by Pt-Cu nanoparticles, where high catalytic activity and stability are maintained. More importantly, increasing Cu2+ can further enhance the catalytic performance. Tuning the second metal chemical state of Pt-based bimetallic alloy can be an effective approach to develop new catalysts for CWAO technology. [Display omitted] • Degradation of phenol was achieved over Pt-M/C (M=Pb and Cu) at 100 °C. • Pt-M alloy structures mainly contained Pt0 and M2+ were built. • Higher M2+ concentration of Pt-M alloy contributed to the enhanced stability. • Higher M2+ concentration kept Pt0 being oxidized during the reaction process. [ABSTRACT FROM AUTHOR]

Recently, most seizure prediction methods mainly utilize pure CNN or Transformer model, which cannot extract local and global features simultaneously. To this end, we propose an Electroencephalogram (EEG) seizure prediction method based on Transformer guided CNN (TGCNN), which combines the complementary advantages of CNN and Transformer. The proposed method first use short-time Fourier transform (STFT) to extract time–frequency features from EEG signals. Then, these features are fed into the alternating structure to model both local feature and long-distance dependencies, which can overcome both the deficiency of long distance dependence in CNN and the lack of local features in Transformer. Finally, the prediction result is obtained through a global average pooling layer and fully connected layer. The proposed method achieves sensitivity of 91.5%, false prediction rate (FPR) of 0.145/h, and area under curve (AUC) of 93.5% on CHB-MIT database and 82.2% sensitivity, 0.06/h FPR, and 83.5% AUC on Kaggle dataset. • We propose an EEG seizure prediction method based on Transformer guided CNN. • Our method can extract local and global features for EEG seizure prediction. • We propose a new Transformer module for EEG seizure prediction. [ABSTRACT FROM AUTHOR]

Bubble dynamics in bulk flow has been widely investigated at high-frequency actuation (normally above 20 kHz, up to several MHz); however, bubble translation in microfluidics has seldom been investigated, especially at low frequencies (below 10 kHz). This paper presents a study on bubble translation in a resonator-shaped microfluidic chamber. The experimental results show that under the actuation at 1 kHz, the bubbles are observed to occur near the center of the chamber, grow up in size and then move upstream against the main flow. The bubble translation upstream against the main flow is attributed to the attraction of the image bubbles which exist behind the chamber sidewall. [ABSTRACT FROM AUTHOR]

[Display omitted] Sarcoplasmic/endoplasmic reticulum Ca2+ ATPase 2 (SERCA2) is vital to maintain intracellular calcium homeostasis, and its redox Cys674 (C674) is the key to regulating activity. Our goal was to investigate whether the redox state of SERCA2 C674 is critical for cardiac fibrosis and the mechanisms involved. Heterozygous SERCA2 C674S knock-in (SKI) mice, in which half of C674 was substituted by serine, were used to mimic the partial loss of the reactive C674 thiol in pathological conditions. In cardiac fibroblasts, the substitution of C674 thiol increased Ca2+ levels in cytoplasm and mitochondria, and intracellular ROS levels, and activated calcineurin/nuclear factor of activated T-lymphocytes (NFAT) pathway, increased the protein expression of profibrotic factors TGF beta 1 (TGF-β1), alpha smooth muscle actin, collagen I and collagen III, and promoted the transformation of cardiac fibroblasts to cardiac myofibroblasts, which could be reversed by calcineurin/NFAT inhibitor, SERCA2 agonist, or ROS scavenger. Activation of SERCA2 or scavenging ROS is beneficial to alleviate cardiac fibrosis caused by the substitution of C674. In conclusion, the partial loss of the reactive C674 thiol in the SERCA2 exacerbates cardiac fibrosis by activating the calcineurin/NFAT/TGF-β1 pathway to promote the transformation of cardiac fibroblasts to cardiac myofibroblasts, which highlights the importance of C674 redox state in maintaining the homeostasis of cardiac fibroblasts. SERCA2 is a potential therapeutic target for the treatment of cardiac fibrosis. [ABSTRACT FROM AUTHOR]

This paper presents the experimental study on the flow field and mixing enhancement in a novel micromixer with actuation. Its demonstrated that asymmetric vortex can be generated in the mixer and enhance the mixing performance greatly. The details of the vortex are displayed clearly by tracing the fluorescent dye. The strength of the vortex can be controlled by adjusting the applied voltage. The numerical simulation by Ansys Fluent shows that the streamlines under actuation is in accordance with experimental results. The large-scale vortex generated under actuation can be applied for flow control and operation as well as mixing enhancement in microfluidics. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a numerical investigation of heat transfer and lubricant depletion on the hard disk surface in a heat-assisted magnetic recording (HAMR) system. The disk consists of multilayer structures with anisotropic thermal properties on the top-recording layer and a thin layer of lubricant on the top surface. The heat generated by the laser results in the non-uniform temperature filed and subsequent lubricant depletion on the disk top surface. Two multilayer structures with different alloy materials on the top layer are studied. The results show that the top-layer alloy anisotropy does affect both temperature distribution and lubricant depletion, with the extent of the effect depending on the thermal diffusivity ratio (defined as the ratio of the thermal diffusivity along x–y direction to that along z direction on the top layer) as well as the alloy material of the top layer. For the top-layer alloy with inferior thermal properties, the effect of anisotropy is more significant at the range of thermal diffusivity ratio from 1 to 0.5. With a further reduction in this ratio, the anisotropy of the top-layer material does not show further noticeable effect. [Copyright &y& Elsevier]

Abstract: In this study, we present a computer-aided preoperative planning system (Liver 2.0) for liver surgery based on CT images. The proposed system is composed of two main sections: image analysis and treatment planning. The first module provides effective image analysis algorithms and three-dimensional (3D) visualization of all relevant anatomic and pathologic structures. The later module provides the resection tools and measurement tools for virtual liver surgery planning. The surgeon can flexibly specify resection regions with resection tools, which can be applied selectively to different structures, and obtain the quantitative analysis of distance, area, volume and angle with measurement instruments. The results of clinical trial indicate that the virtual liver resections provide a reasonable and useful basis for preoperative planning, and it also can be used for educational purposes. [Copyright &y& Elsevier]

The presence of turbine blade tip clearance can cause tip leakage losses and enhance the thermal load on the tip region. The continuously increasing inlet temperature of the turbine poses a tremendous challenge for turbine blade tip design. Reasonable turbine blade tip configurations can effectively reduce the thermal load on the tip region and enhance aerodynamic characteristics. Here, surface Nu distributions of flat, cavity, and five modified tip configurations are obtained through transient liquid crystal measurement technology. Furthermore, a numerical study combined with experimental results is conducted to investigate the aerothermal characteristics of the tip regions for each configuration. The results indicate that the flat tip (FT) has the highest tip surface thermal load and maximum aerodynamic loss, and the cavity structure can effectively reduce the average Nu on the tip surface. Among the five modified configurations, the SS ribbed configuration (SRT) and the lateral ribs configuration (SLCT) exhibit relatively optimal aerothermal performance. Specifically, compared to FT, the SRT tip configuration shows an average Nu reduction of 27.4 % on the tip surface and a 16.3 % decrease in tip clearance leakage compared to FT; the average Nu on the SLCT tip surface and the tip clearance leakage relative to the FT are reduced by 27.2 and 17.3 %, respectively. [ABSTRACT FROM AUTHOR]

High-bit images can show more detail than low-bit images do. False contours in the low-bit images should be suppressed when converting low-bit images to high-bit ones. In this paper, a contrast-aware bit depth enhancement (BDE) module is proposed based on the visual perceptual feature which models the relationship of contrast sensitivity and image bit depth. And a bit depth enhancement network is constructed by the cascade of this module. The experimental results show that the bit depth enhancement algorithm based on this network structure has the best or second-best peak signal-to-noise ratio (PSNR) and structural similarity (SSIM) metrics when compared with the related algorithms, and on average, our PSNR (40.20 dB) is only 1.03% and SSIM (0.9681) is only 0.11% lower than that of the state-of-the-arts, but uses 6.7% fewer parameters (11.2M). And visual comparisons show that our algorithm can effectively suppress false contours and color distortions, resulting in high-bit images with better quality. • Apply contrast sensitivity function (CSF) to bit-depth enhancement. • Propose a contrast-aware bit-depth enhancement (BDE) module. • Propose a lightweight bit-depth enhancement algorithm. [ABSTRACT FROM AUTHOR]

Hydrogen production from formaldehyde aqueous solution at room temperature shows a unique advantage regarding the bi-functional reaction route. MnO 2 was reported to be an active catalytic material for this process, especially after coating with carbon composite for improved active site distribution. Here, we unravel that the conversion of formaldehyde can be treated as two tandem half-reactions: the oxidative dehydrogenation (ODH) of formaldehyde and the hydrogen evolution reaction (HER). β-MnO 2 in a physical mixture with carbon (i.e., XC-72R, graphene) enhances both formaldehyde conversion (from 13% to 19.5%) and hydrogen productivity (from 22.35 μmol mg−1 h−1 to 33.86 μmol mg−1 h−1) by a synergistic effect of the phase separation catalyst in terms of electron redistribution and transport over the active sites. The catalyst examination supported by DFT calculation shows relatively low activation energy and band gap of β-MnO 2 + C with a density of states spanning the Fermi level. The discovery of this novel synergistic catalytic effect: a phase separation catalyst with cooperative enhancement, provides new insight into the area of tandem catalysis. • Physical mixing of MnO 2 and C shows high activity in H 2 evolution from formaldehyde oxidation. • A tandem route is proposed between formaldehyde oxidative dehydrogenation and hydrogen evolution over the MnO 2 surface. • The addition of C makes the solution similar to a slurry, facilitating the electron transfer and redistribution on MnO 2. [ABSTRACT FROM AUTHOR]

Sirtuin 6 (SIRT6) is a chromatin-associated deacetylase that plays a leading role in genomic stability and aging. However, the precise role of SIRT6 in atherosclerosis, an aging-associated cardiovascular disease, remains elusive. This study aims at defining the role of SIRT6 in atherosclerotic lesion development. SIRT6 messenger RNA and protein expression are markedly decreased in atherosclerotic aortas of apolipoprotein E-deficient (ApoE(-/-)) mice fed a high-cholesterol diet. SIRT6 was knocked down in ApoE(-/-) mice using small hairpin RNAs (shRNAs) lentivirus injection. SIRT6-shRNA-treated ApoE(-/-) mice showed impaired endothelium-dependent vasodilation, increased plaque size (in aortic sinus, aortic root and en face aorta), and augmented plaque vulnerability (evidenced by increased necrotic core areas and macrophage accumulation and reduced collagen content). At the cellular level, SIRT6 depletion by RNA interference in human umbilical vein endothelial cells significantly increased monocyte adhesion to endothelial cells by inducing the expression of intracellular adhesion molecule-1. Consistently, intracellular adhesion molecule-1 expression was significantly upregulated in aortic endothelium of SIRT6-shRNA-treated ApoE(-/-) mice compared with controls. In sum, the aforementioned findings suggest that SIRT6 is a primary negative regulation factor in endothelial dysfunction and atherosclerosis development. As a result, SIRT6 is a promising therapeutic target for treating atherosclerosis and its cardiovascular complications. [ABSTRACT FROM AUTHOR]

Regulatory T cells (Tregs) characterized by the transcription factor forkhead box P3 (FoxP3) are crucial for maintaining immune tolerance and preventing autoimmunity. However, FoxP3 does not function alone and Helios is considered a potential candidate for defining Treg subsets. In this study, we investigated the expression and function of Helios for identifying Tregs in childhood precursor B-cell acute lymphoblastic leukemia (pre-B ALL). Our results demonstrated that patients with pre-B ALL had a higher percentage of Helios + FoxP3 + CD4 + Tregs. And there was a positive correlation between the expression of Helios and the suppressive function of Tregs, the risk gradation of ALL. Helios in combination with CD4 and FoxP3 may be an effective way to detect functional Tregs in pre-B ALL by promoting the secretion of transforming growth factor (TGF)-β1. Furthermore, Helios + Tregs could regulate angiogenesis in the BM niche of pre-B ALL via the VEGFA/VEGFR2 pathway. We also found Helios + Tregs decreased apoptosis rate of nalm-6 cells by up-regulating the expression of anti-apoptosis protein Bcl-2. In summary, these data strongly imply the physiological importance of Helios expression in Tregs, and suggest that the manipulation of Helios may serve as a novel strategy for cancer immunotherapy. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a numerical investigation of heat transfer and lubricant depletion on the hard disk in a heat-assisted magnetic recording (HAMR) system. The heat is induced by a laser pulse shooting down from a slider flying over the disk coated with a thin layer of lubricant. The main mechanisms to cause the lubricant depletion are examined by taking into account of effects associated with evaporation enthalpy, thermal induced surface tension and initial lubricant film thickness. The results show that the evaporation has a dominant effect at a lower evaporation enthalpy, while the thermocapillarity plays a main role at a higher evaporation enthalpy. The lubricant depletion is also found to be affected by the initial thickness of the lubricant film, mainly through the influence on the evaporation rather than on the thermocapillarity. In addition, the effect of lubricant accommodation coefficient on the evaporation has been addressed for the first time in the present study. It is found that a full accommodation assumption adopted in previous numerical studies may overestimate the actual evaporation rate, and a suitable value for the accommodation coefficient between 0 and 1 is required in the prediction in order to yield a good agreement between the simulation results and the experimental data. [Copyright &y& Elsevier]

Abstract: With the aim toward realizing polymerase chain reaction (PCR) of deoxyribonucleic acid (DNA) in plug-based capillary platforms, this paper reports the theoretical and experimental results of thermocapillary actuation for temperature cycling with an arbitrary ramping function. Two concepts were investigated: (a) actuation and spatial temperature cycling with three heaters and (b) actuation and temporal cycling with two heaters. The paper first describes the analytical models of both concepts. The model considers the spatio-temporal heat transfer effects, which is coupled with the surface tension driven movement of the plug. In the experiments, both temperature field and plug motion were measured and evaluated. The temperature field was captured by an infrared thermal tracer camera. The position of the plugs was automatically captured and evaluated with a CCD camera. Finally, analytical and experimental results are compared and discussed. [Copyright &y& Elsevier]

Highlights: • Xanthan gum has limited effect on the soil strength at initial stage. • Drying leads to xanthan gum bonding strength and soil cohesion increase. • Shrank brittle dry xanthan gum generates strengthening effect variability in soil. Abstract Biopolymers are environmentally friendly materials which have shown their competitiveness in civil engineering. Researchers mentioned that drying is the crucial factor in the behaviour of biopolymer treated soil, but how it influences soil strength is still unclear. This study explains how drying influences biopolymer treated soil strength, especially for the behaviour of xanthan gum biopolymer and sand interaction during the drying. The xanthan gum biopolymer presented limited effect in the sand when water content was in a high level. With the continuous evaporation of water, bonding property from the biopolymer gradually showed up which lead to the increase of the soil shear strength (40 °C oven). However, when sample dried at the 20 °C room temperature condition, the outer surface of the sample was cemented and crystallised by the xanthan gum biopolymer while the inner part was still moist and weak cross-linked, which lead to the weak shear strength. When the water became completely evaporated, samples under those two different drying conditions presented a significant increase in shear strength. But these results were inconsistent as the biopolymers shrank and became brittle which lead to a variability of cohesion of soil strength. The measured biopolymer bonding property presented consistent results to the findings in the direct shear tests. The schematic diagram of sand motion was proposed to illustrate the biopolymer treated sand shear performance and gave the further explanation of variability of biopolymer treated sand strength. [ABSTRACT FROM AUTHOR]

The aberrant proliferation and migration of pulmonary arterial smooth muscle cells (PASMCs) are critical contributors to the pulmonary vascular remodeling that occurs during the development of Pulmonary arterial hypertension (PAH). Krüppel-like Factor 7 (KLF7) has been reported to be involved in the development of certain cardiovascular diseases. However, the role of KLF7 in PAH remains unknown. Here, we aimed to explore whether KLF7 mediates the proliferation and migration of PASMCs and its underlying mechanism. In this study, Sprague Dawley rats were exposed to 60 mg/kg monocrotaline (MCT) for 3 weeks to induce PAH and human PASMCs were stimulated with 20 ng/ml platelet-derived growth factor-BB (PDGF-BB) for 24 h to induce proliferation and migration. The mRNA and protein expression of KLF7 were significantly down-regulated in MCT-induced PAH rats and PDGF-BB-treated PASMCs. Under normal conditions, KLF7 knockdown obviously promoted PASMCs proliferation and migration, whereas KLF7 overexpression exhibited the opposite effects. Furthermore, PDGF-BB promoted the PASMCs proliferation and migration, increased the cell proportion in S phase, which was significantly attenuated by overexpression of KLF7. Mechanistic investigation indicated that KLF7 through activation its target protein, the cell cycle inhibitor p21, which finally leading to the inhibition of PASMCs growth. Consistently, UC2288, a specific inhibitor of p21, partially reversed the PASMCs proliferation inhibited by KLF7 overexpression. Taken collectively, the data suggested that KLF7 inhibits PASMCs proliferation and migration via p21 pathway and it may be used as a new therapeutic target for the PAH. [ABSTRACT FROM AUTHOR]

We investigated the particle size effect on the thermophoresis of colloidal particles in an aqueous medium via a microfluidic approach. A microfluidic device was used to directly observe and quantitatively characterize the thermophoretic behaviors of charged hydrophobic polystyrene particles within a wide diameter range from 100 nm to 5 μm dispersed in deionized water. Our experimental findings showed an interesting particle size effect – a sign switch of the thermodiffusion coefficient from positive to negative with increasing particle size from submicron to micron. Moreover, a linear size-dependence of the thermodiffusion coefficient for micron-sized particles was obtained. Through comparing our experimental results with Duhr–Dhont’s analytical model that includes effects of the electric double layer ionic shielding and the hydration entropy, we found that both the sign switch and the particle size linear dependence can be explained by this model. In addition, a separation of submicron particles from micron-sized particles was demonstrated experimentally via the particle size-dependent sign switch of thermophoresis. [ABSTRACT FROM AUTHOR]

Background Aplastic anemia (AA) is an immune-mediated disorder and mainly related to active destruction of hematopoietic cells by effector T lymphocytes. T helper (Th) 22 cells characterized as a novel subset of CD4 + T cells participate in the pathogenesis of autoimmune and hematological diseases. However, the role of Th22 subset in AA remains unknown. Methods 31 untreated AA patients and 30 healthy controls were included in this study. The percentages of Th22, Th17 and pure Th17 cells in peripheral blood were detected by flow cytometry. ELISA to measure interleukin (IL)-22 and IL-17A plasma levels and qRT-PCR for the mRNA levels of Th22 and Th17 related molecules were performed. Results The proportions of Th22, pure Th17, Th17 cells and plasma levels of IL-22 were significantly lower in untreated AA patients than those in normal controls. A positive correlation was found between Th22 and pure Th17 cells in AA. Moreover, percentages of Th22 cells correlated positively with reticulocyte counts and percentages. In addition, STAT3/STAT5 mRNA expression ratio was elevated in AA patients. Conclusion Together, our results showed Th22 cells correlating with clinical characteristics of AA patients, indicating a possible role of Th22 immune response in the pathogenesis and therapeutic intervention of AA. [ABSTRACT FROM AUTHOR]

Highlights: [•] In cardiomyocytes, ET-1 treatment resulted in significant upregulation of COX-2 expression and activity. [•] Both COX-2 inhibitors and COX-2 RNA interference suppressed cardiomyocyte hypertrophy induced by ET-1. [•] Calcineurin/NFATc3 signaling pathway participated in the transcriptional regulation of COX-2 by ET-1. [ABSTRACT FROM AUTHOR]

Freezing phenomena of water droplets on metal surfaces widely exist in nature and industry. While the freezing of a sessile water droplet has been extensively studied, here we report an experimental and thoeritical investigation of the freezing characteristics of a deposited water droplet on cold hydrophilic and hydrophobic aluminum surfaces and also compare them with those of the sessile droplet. The results show that the deposited droplet starts to freeze from the liquid-solid interface after the spreading contact line is arrested by the cold surface and the recalescence stage observed during the freezing of a (supercooled) sessile water droplet does not appear. Furthermore, under our experimental conditions of surface temperature and wettability, the frozen shapes of the deposited droplets on the hydrophilic and hydrophobic surfaces are only dependent on the surface temperature while those of the sessile droplets unnoticeably change with the surface temperature but significantly vary with the surface wettability. Additionally, we present a scaling analysis to describe the temporal evolution of freezing front and the relationship between freezing time and surface temperature for the deposited droplet. [Display omitted] • Freezing characteristics of the deposited water droplet on cold hydrophilic and hydrophobic surfaces are investigated. • The frozen shape of the deposited droplet is mainly dependent on surface temperature. • A modified correlation is proposed to describe the freezing front evolution. • A scaling analysis shows the dependence of freezing time on surface temperature. [ABSTRACT FROM AUTHOR]

Abstract: In living donor liver transplantation, the volume of the potential graft must be measured to ensure sufficient liver function after surgery. Couinaud divided the liver into 8 functionally independent segments. However, this method is not simple to perform in 3D space directly. Thus, we propose a rapid method to segment the liver based on the hepatic vessel tree. The most important step of this method is vascular projection. By carefully selecting a projection plane, a 3D point can be fixed in the projection plane. This greatly helps in rapid classification. This method was validated by applying it to a 3D liver depicted on CT images, and the result was in good agreement with Couinaud’s classification. [Copyright &y& Elsevier]

Abstract: Electrokinetic micropumps are fabricated using 6–8μm ODS beads into 320–700μm fused-silica capillaries. The fabricated bead column is characterized by measuring the porosity and tortuosity. Experiments are carried out to study the flow characteristics under the effects of the packing conditions, solution properties and applied electric field strength. Specifically, the EO flow rates are measured using two independent methods: the test column method and the electric current monitoring method. Thus, the zeta potential of the packing beads can be obtained. In addition, a theoretical model is presented, and the theoretical predictions are found in reasonable agreement with the experimental data. [Copyright &y& Elsevier]