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AbstractIn models of fluid dynamics, the magnetic field is essential for preserving the stability of flow streams and found applications in magnetic resonance imaging, magnetic levitation, and geophysical exploration. Recognizing the significance of this magnetic influence, we aim to investigate the behavior of flow within a three-dimensional squeezed film of Casson fluid situated between two rotating disks, under the influence of an induced magnetic field and the Reynolds viscosity model. The study also meticulously examines the heat and mass transfers, taking into account the effects of thermo-diffusion and diffusion-thermo. The resulting torque on both the upper and lower surfaces is analyzed and presented in a tabulated format. The normalized system of equations is transformed into a set of first-order differential equations, which are then solved using the bvp4c numerical solver in MATLAB. The impacts of various parameters are graphically illustrated in two different scenarios (ϒ=0.0,0.5), i.e., constant and variable viscosity. It is observed that when the variable viscosity parameter is set to zero, the azimuthal velocity profile experiences a more pronounced increase as the rotational parameter rises. Conversely, the azimuthal magnetic profile exhibits a more significant decrease when considering the influence of the variable viscosity parameter. Finally, the results are compared with previous studies in the literature for a limiting case, and error is reduced between 0.000003% and 0.000002%. [ABSTRACT FROM AUTHOR]

AbstractThe intension of recent analysis is to discuss the radiated magnetized flow of Maxwell nanoliquid. Flow is induced due to stretching the surface. Convective and zero mass flux conditions are taken into account. Influence of Soret and Dufour are under consideration. Internal heat source, magnetic field and thermal radiation are discussed in energy expression. Random diffusion and thermophoresis characteristics in presence of chemical reaction are deliberated. Thermal conductivity and viscosity depend upon temperature. Similarity transformation is utilized to transform nonlinear partial differential systems into ordinary systems. ND-solve technique is used to get the numerical solutions for nonlinear nondimensional system. Graphical analysis for flow, concentration and thermal distribution versus emerging variables are examined. Computational outcomes for solutal transport rate and Nusselt number via sundry variables are explored. Velocity profile declines against magnetic field, whereas reverse trend found for temperature profile. Thermal field has increasing trend for thermal Biot and Dufour numbers. Larger Maxwell variable has opposite effect on flow field. [ABSTRACT FROM AUTHOR]

AbstractA theoretical study is carried out to explore the heat and mass transfer features in the flow of two types nanofluid, i.e., Al2O3/H2O micropolar nanofluid and (Al2O3+Ag)/H2O hybrid nanofluid, adjacent to a solid sphere. Furthermore, simultaneous effects of linear thermal radiation and chemical reaction are also explored on the heat and mass transfer characteristics. In mathematical formulation basic conservation laws are utilized along with the Soret and Doufer effects as a coupling agents in the energy and mass concentration equations. The normalized variables are used to transform the governing system of non-linear partial differential equations into the system of dimensionless partial differential equations. Stream function reduces the number of dependent variables and the resulting system is solved numerically by Keller box method. Several plots are presented to explore the impact of involved parameters on the different profiles and engineering interest quantities for both types of fluids. The temperature profile and Nusselt number are large in magnitude for hybrid nanofluid as compared to Al2O3/water based nanofluid. The heat transfer and mass transfer rates rises with thermal radiation parameter and chemical reaction parameter, respectively. [ABSTRACT FROM AUTHOR]

Abstract There is a awakening interest in applying bioconvective nanofluids in permeable media. As such, this article aims to numerically investigate boundary layer flow over a plate embedded in a porous medium filled with nanofluid with motile gyrotactic microorganisms. Consequence, mass and heat transmission efficiency in engineering, technological, and industrial domains is improved. Thus, heat and mass transmission with impacts of radiation and activation energy on the horizontal porous plate are analyzed with microorganisms. Ordinary differential equations are established from nonlinear leading Partial Differential Equations by implementing similarity variables. After that, the resultant ordinary differential equations are numerically tackled employing the BVP4C method, build-in package of MATLAB. From tables, it is evident that when the velocity parameter is one, skin friction is zero, which exhibits no opposition at the fluid-solid surface. The impacts of pertinent parameters upon nondimensional boundary layer outlines are deliberated. It is worth mentioning here that the impact of the magnetic field parameter ( 1 ≤ M ≤ 3 ) on velocity is drawn, and the graph depicts that the velocity is diminished by increasing the value of the magnetic parameter. It is because when the magnetic field is given perpendicular to the liquid’s surface, the generated magnetic impact causes the liquid to flow with a resistive form of force, which reduces its speed for the solutal resistance is increased by activation energy ( 1 ≤ E ≤ 3 ) but decreased by Lewis number ( 1 ≤ L e ≤ 3 ) , and chemical reaction constant ( 1 ≤ σ ≤ 3 ) . Finally, current inquiry can helpfully enhance thermal conductivity, viscosity, convective heat transmission, and thermal diffusivity linked to those base fluids. The current investigation reveals that the Lewis number and chemical reaction constant tend to decay thickness of concentration boundary layer. [ABSTRACT FROM AUTHOR]

In this paper, a new three-level implicit and fourth-order compact conservative difference scheme is developed for the generalized symmetric regularized long wave equations. The proposed scheme adopts a new time discretization method. The conservation of the new compact scheme is proved, and the discrete conservation laws are obtained. The priori estimation in the maximum norm is discussed by the discrete energy method and mathematical induction. Based on the priori estimation and Brouwer's fixed point theorem, the unique existence of the difference solution is proved. It is proved that the compact difference scheme is unconditionally convergent and stable in the maximum norm, and its convergence order is the fourth order in space and the second order in time. A decoupled and linearized iterative algorithm is proposed to calculate the nonlinear algebraic system generated by the compact scheme, and its convergence is proved. Several numerical experiments are performed to prove the efficiency and reliability of the proposed numerical scheme and to confirm the results obtained from the theoretical analysis. [ABSTRACT FROM AUTHOR]

Ganoderma lucidum (G. lucidum) is a famous medicinal fungus used as a traditional medicine for generations in China. Among bioactivities that G. lucidum possesses, the anti-tumor effect has aroused extensive interests. In this study, one new triterpene (1) was isolated from 90% ethanol extract of the dried fruiting bodies of G. lucidum. Its structure was determined based on the analysis of its spectroscopic data, including 1 D and 2 D NMR and MS spectra. Furthermore, 1 elicited moderate anti-tumor activities (IC50 values of 15.38 ± 0.34 and 18.61 ± 0.55 μM for A549 and HepG2 cells, respectively) compared with cisplatin which was employed as the positive drug with IC50 values of 8.21 ± 0.17 and 5.36 ± 0.29 μM for A549 and HepG2 cells, respectively. The mechanism study by RT-qPCR and western blot analysis suggested that the p53/caspase-3 pathway is involved in the 1-induced apoptosis. [ABSTRACT FROM AUTHOR]

Research on turbulent drag reduction has been limited owing to the limitations of existing parameters used for the identification of vortex structures. As a new and more suitable vortex parameter, Liutex provides a novel research method for turbulence control. We used a channel with a transverse groove structure as the research model and employed large-eddy simulation method based on Liutex to study the influence and mechanism of the transverse groove structure on the watershed. The analysis revealed that the transverse groove structure significantly inhibited the vortex intensity, and this effect diminished with the increase of the normal height. Moreover, the transverse groove structure could maintain the stability of the flow vortex and restrain the hairpin vortex. The fundamental action mechanism of the groove structure pertained to slip condition of the bottom surface along the flow direction, which was essential for conveying the bottom fluid. Furthermore, the transverse groove structure could significantly reduce the overall increase in the vortex intensity in the transition layer, and the fluctuation of the vortex intensity in the logarithmic layer was lower under the action of the groove structure. This case can guide the application of the new vortex identification method in turbulence drag reduction. [ABSTRACT FROM AUTHOR]

A D-shaped photonic crystal fibre filled with liquid crystal was demonstrated as an amphibious sensor for detection of both temperature and refractive index, when combined with plasma materials. Specifically, the optical component is implanted into a complete optical system ensuring modulation of the external electric field. When the refractive index of the external solution changes from 1.0 to 1.6, the y-polarised mode has a loss spectrum with a wavelength sensitivity of up to 2275 nm/RIU, and the corresponding amplitude sensitivity is −88.2RIU−1. When the perceived temperature changes from 15°C to 50°C, the temperature of the sensor is correspondingly expressed as the maximum wavelength sensitivity of 9.09 nm/°C and the amplitude sensitivity of −0.311°C−1. In addition, the actual micro-operation processes have been studied in detail, such as polishing depth, coating thickness and coating method. This provides practical ideas for real-time sensing analysis that requires harsh environments. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the mechanism by which KLF6-SV1 promoted lung cancer metastasis through tumor-associated macrophages (TAMs). Plasmid transfection was used to construct cells that upregulated or silenced gene. Tumor-bearing mouse model was established using A549 cells. SP staining was performed to detect the CD163 and CD68. Six-well plates and Transwell chamber were used for co-culture of lung cancer A549 cells and macrophages. CCK-8 and Transwell assay were applied to detected the cell viability and migration respectively. Protein and mRNA were tested by Western blot and quantitative real-time polymerase chain reaction (qRT-PCR).KLF6-SV1 overexpression promoted the expression levels of TWIST1 and CCL2, and also induce macrophage polarization to M2 and epithelial-mesenchymal transition (EMT). In vitro experiments showed that KLF6-SV1 might regulate the migration of lung cancer cells by regulating the expression of TWIST1 and CCL-2. M2 macrophages did not affect the expression of KLF6-SV1, TWIST1 and CCL-2. The co-culture system could up-regulate the EMT of A549 cells.Overexpression of KLF6-SV1 promoted the expression of TWIST1 and CCL2, and up-regulation of TWIST1 expression might promote the infiltration of M2 macrophages, which promoted the involvement of EMT in the metastasis of lung cancer cells. [ABSTRACT FROM AUTHOR]

A dual communication band single-polarization photonic crystal fibre polarizing filter based on surface plasmon resonance is presented in this paper. Numerical simulation results demonstrate that the resonance strength of x- and y-polarized direction can reach 569.83 and 719.25 dB.cm−1 simultaneously at the communication wavelength of 1.31 and 1.55 µm. By filling liquid analyte, the confinement loss of x- and y-polarized direction can simultaneously reach 831.7 and 580.53 dB.cm−1 at the wavelength of 1.31 and 1.55 µm. Furthermore, when the fibre length L is equal to 700 µm, the peak value of the crosstalk can reach 493.86 and −323.67 dB at the same time at the wavelength of 1.31 and 1.55 µm, and when the length of the fibre L is 400 µm, the bandwidths of the crosstalk better than 20 dB and less than −20 dB are about 160 and 210 nm, respectively. These performances make it an ideal candidate for designing dual-band polarization filter equipment. [ABSTRACT FROM AUTHOR]

The coupled viscous Burgers' equations have been an interesting and hot topic in mathematics and physics for a long time, and they have been solved by many methods. In order to make the numerical solutions more accurate, this paper introduces a new method to solve the equations. Compared to other methods, the present method can obtain higher accuracy with fewer nodes. Several numerical examples show the high accuracy of this method. [ABSTRACT FROM AUTHOR]

Generalized plane strain state is assumed and stress-based finite strip method is formulated for analysis of unidirectional laminates with matrix microcracks. Total complementary potential energy is minimized and fourth-order Euler Lagrange governing equations are presented. This stress-based generalized plane strain approach analyzes general layup and loading conditions. It provides flexibility to control the number of finite strip nodal lines within each lamina; hence, stress behavior can be predicted across each lamina at the desired location of the structure. Along with all of the capabilities which are common with finite strip methodology based on plane strain assumption, this current work has extended the analysis of the cracked laminate. For example, by incorporating behavior of the out of the plane shear stress, boundary conditions including natural boundary conditions are imposed appropriately to solve governing Euler's equations. Results are compared with previously developed displacement-based formulation in the literature for cracked laminates. It has already been shown that a stress-based plane strain approach enhances variation-based cracked laminate analysis where only the case of cross-ply laminate under tension is considered. This current work applies generalized plane strain-based finite strip methodology to carry out analysis under different loading conditions. [ABSTRACT FROM PUBLISHER]

Glutamate dehydrogenase (GDH) protein ofStreptococcus suiscan be used for detection ofS. suisinfection and protection of pigs againstS. suisinfection. Acetate is a primary inhibitory metabolite for cell growth and formation of GDH protein. In this study, theptsGgene, which encodes the integral membrane permease IICBGlcin the phosphotransferase system, was deleted and the effect of this deletion on the expression of GDH protein was investigated. The plasmids containingglfZ.mobilis(encoding glucose facilitator)–glkE.coli(encoding glucokinase) orgalPE.coli(encoding galactose permease)–glkE.coliwere transformed intoptsGmutant cells to recover the cell growth and glucose utilization ofptsGmutant. The mutants with deletion ofptsGdecreased the accumulation of acetate; and higher cell density and GDH protein concentration were obtained with theptsGmutants containingglf–glkorgalP–glk. When theptsGmutant containingglf–glk(SSGGFK) was used for expression of GDH protein, the cell density (optical density OD600of 2.68) and the concentration of GDH protein (42.34 mg/L) were highest, with an increase by 12.61% and 14.84%, respectively, compared with the parental strain (SSG). The acetate accumulation was reduced to 2.35 g/L, i.e. a 37.33% decrease compared with the SSG strain. High concentration of GDH protein was obtained with reduction of acetate accumulation through gene modification of the phosphotransferase system. This can decrease the production cost of the subunit vaccine of GDH protein and provide theoretical foundation for high-level expression of other recombinant proteins. [ABSTRACT FROM AUTHOR]

Organophosphorus pesticides (OPs) and carbamate pesticides (CPs) are among the most widely used pesticides in China, playing a major role in protecting agricultural commodities. In this study, we determined the cumulative acute exposure to OPs and CPs of Shanghai residents from vegetables and fruits (VFs). The food consumption data were obtained from the Shanghai Food Consumption Survey (SHFCS) of 2012–14 including a total of 1973 participants aged 2–90 years. The pesticide residue data were obtained from the Shanghai monitoring programme during 2008–11 with 34 organophosphates and 11 carbamates analysed in a total of 5335 samples of VFs. A probabilistic approach was performed as recommended by the EFSA, using the optimistic model with non-detects set as zero and with processing factors (PFs) being used and the pessimistic model with non-detects replaced by limit of detection (LOD) and without PFs. We used the relative potency factor (RPF) method to normalise the various pesticides to the index compound (IC) of methamidophos and chlorpyrifos separately. Only in the pessimistic model using methamidophos as the IC was there was small risk of exposure exceeding the ARfD (3 µg kg–1bw day–1) in the populations of preschool children (0.029%), school-age children (0.022%) and adults (0.002%). There were no risk of exposure exceeding the ARfD of methamidophos in the optimistic model and of chlorpyrifos (100 µg kg–1bw day–1) in both optimistic and pessimistic models in all three populations. Considering the Chinese habits of overwhelmingly eating processed food (vegetables being cooked, and fruits being washed or peeled), we conclude that little acute risk was found for the exposure to VF-sourced OPs and CPs in Shanghai. [ABSTRACT FROM AUTHOR]

An ultra-short polarization beam splitter based on dual-core photonic crystal fibre with square lattice is proposed. Numerical results show that an ideal coupling length and coupling length ratio can be achieved by changing the pitch in two polarizations and the ellipticity. The length of splitter is, the bandwidth is about 70 nm as the extinction ratio lower thanat the wavelength of. The characteristic of the short length is rare in previous literatures which could widely apply to integrated optical communication systems. [ABSTRACT FROM AUTHOR]

A kind of photonic crystal fibre polarization filter with round lattice based on surface plasmon resonance is proposed. Complete coupling happens between core mode and second-order surface plasmon polariton (SPP) mode when the phase-matching condition is satisfied. We can adjust the resonance point and strength in two polarizations by changing the fibre birefringence and the thickness of gold film. Numerical simulation with the finite-element method shows that the resonance strength can reach 364.8 dB/cm in they-polarized direction at the communication wavelength of 1550 nm, when the diameter of big air holes that lead to the birefringence is 2.0 m and the thickness of gold film is 26 nm. Moreover, when the fibre length is 800 m, the peak value of the crosstalk can reach 231.8 dB and the bandwidth of the crosstalk better than 20 dB can reach 130 nm. This makes it a promising candidate for polarization filter devices. [ABSTRACT FROM PUBLISHER]

Lamprophyre dikes emplaced in a Jurassic granite at the southeastern margin of the North China Craton (NCC) carry different types of xenoliths. Here, we report a combined study of zircon U–Pb ages and whole-rock geochemistry of the xenoliths, as well as an Ar–Ar age of the lamprophyre, providing constraints on the sources of the magmatism and tectonic evolution in the southeastern margin of NCC. Phlogopite from the lamprophyre dike gave a40Ar/39Ar plateau age of 116.15 ± 0.33 Ma. The felsic xenoliths can be classified into three groups: monzogranite, banded biotite granitic gneiss, and garnet-bearing gneiss. The internal structures of zircons from the banded biotite granitic gneiss xenolith show complex growth patterns. The mantles of these zircons display low luminance with a concordant SHRIMP U–Pb age of 227 ± 10 Ma. The rims with lighter luminance provide a SHRIMP U–Pb age of 213 ± 10 Ma, both ages are identical within error and significantly different from the ages of the basement rocks in the surrounding Bengbu uplift. However, the age is identical to those of the ultrahigh-pressure metamorphic rocks in the adjacent Dabie–Sulu orogen. In addition, zircon mantle domains of the banded biotite granitic gneiss xenolith have low Th/U ratios (>0.01) and flat HREE patterns ((Yb/Dy)n < 10), which suggest growth in an assemblage with garnet during HP metamorphism. The rim domains show very low Th/U ratios (<0.01) and steep HREE patterns ((Yb/Dy)n > 10), implying growth during exhumation in the absence of a garnet. Our studies show that the banded biotite gneiss represents vestiges of the subducted South China crust injected into or thrust below the North China Craton and provides constraints on the process of underthrusting in a continental collision zone, as well as the Mesozoic tectonic history of the southeastern margin of the NCC. [ABSTRACT FROM AUTHOR]

Association of uteroglobin G38A gene polymorphism and IgA nephropathy (IgAN) risk is still not clear. This investigation was conducted to assess if there was an association between the uteroglobin G38A gene polymorphism and IgAN risk using meta-analysis. The relevant literatures were identified from PubMed, and Cochrane Library on 10 October 2013, and eligible studies were included and synthesized. Seven reports were recruited into this meta-analysis for the association of the uteroglobin G38A gene polymorphism with IgAN risk. In overall population, the A allele and AA genotype were not associated with IgAN risk. Furthermore, the GG genotype was also not associated with IgAN risk in overall population. Interestingly, the association of uteroglobin G38A gene polymorphism with IgAN risk was also not found in Asians and in Caucasians. In the sensitivity analysis, according to Hardy-Weinberg equilibrium test, according to the control source from healthy, the genotyping methods using PCR-RFLP, PCR-SSCP, no association of the uteroglobin G38A gene polymorphism with IgAN risk was found and the results were similar to those in non-sensitivity analysis. In conclusion, the uteroglobin G38A gene polymorphism was not associated with IgAN risk. However, additional studies are required to firmly establish a correlation between the uteroglobin G38A gene polymorphism and IgAN risk. [ABSTRACT FROM AUTHOR]

Phthalate esters (PE) are synthetic chemicals widely used in industry, and have been detected in personal care products (PCP). Recent findings of human reports demonstrated endocrine-disrupting action associated with phthalate exposures. The aims of this study were to (1) measure levels of 11 PE in 198 PCP collected from retail markets in Shanghai and (2) assess daily dermal exposure in adult females and infants. The health risk of cumulative exposure to eight PE on reproductive system function derived from dermal PCP use was further assessed by utilizing the hazard index (HI) approach. Diethyl phthalate (DEP) was the most frequently detected compound (29.8%), followed by diisobutyl phthalate (DiBP) (6.6%). The geometric mean (GM) concentrations of daily exposure to DEP, bis(2-methoxyethyl) phthalate (DMEP), DiBP, dibutyl phthalate (DBP), diphenyl phthalate (DPP), and bis(2-ethylhexyl) phthalate (DEHP) in female adults were 0.018, 0.012, 0.002, 0.001, 0.003, and 0.002 μg/kg body weight (bw)/d, respectively. The GM daily exposure levels to PE in infants and adult females were similar except for DEHP, which was higher in infants. DEP exposure was highest in both subpopulations at either GM or maximal level. All HI of 8 PE were far less than 1, ranging from 0.0002 to 0.005, indicating no cumulative reproductive risks to these populations. DBP, DMEP, and DEHP were three major contributors to the cumulative HI. In summary, the level of phthalate in PCP from Shanghai retail markets posed no apparent cumulative risk to adult females and infants in China. [ABSTRACT FROM AUTHOR]

The samples of sintered Ag joints for power die attachments were prepared using paste of Ag nanoparticles at 240°C and 5 MPa for 3 to 17 minutes. Their microstructural features were quantitatively characterized with scanning electronic microscopy, transmission electron microscopy, X-ray diffraction and image analysis method. The resulting normalized thickness, pore size and porosity decreased, and grain size increased with increasing the sintering time. A time dependence of the formt1/nwithnclose to 2 or 3 can be further derived for the kinetics of the thinning, densification and grain growth within the sintered Ag joints. [ABSTRACT FROM PUBLISHER]

A polarization splitter in three-core photonic crystal fiber with rectangle lattice based on resonant tunneling effect is studied by the finite element method. The transverse-electric (TE) mode polarized light is limited to the launched port and the transverse-magnetic (TM) mode polarized light can directionally couple to the other port due to the large birefringence. A polarization splitter with a coupling length of 2.592 mm, extinction ratios ofERA= –151 dB andERC= –22 dB, insertion losses ofILTE= 0.027 dB,ILTM= 2.89E–15, and 15 dB, and a bandwidth of 29 nm at the communication wavelength of 1550 nm is obtained. The designed polarization splitter exhibits nice performance characteristics under reasonable fabrication tolerance. The characteristics of the polarization splitter are influenced by the effect of surface plasmon resonance. The golden wires infilling into the air holes reduce the coupling length to 1.695 mm. [ABSTRACT FROM AUTHOR]

The objective of the present study was to determine the effectiveness of a soluble dietary fiber, NUTRIOSE®, on body weight, body composition, energy intake and hunger in overweight Chinese men. The volunteers were randomized in double-blind fashion to 250 ml fruit juice supplemented with NUTRIOSE® (Test, n = 60) or a maltodextrin (Control, = 60) at a dosage of 17 g twice daily for 12 weeks. Body weight, body composition were performed at 0, 4, 8 and 12 weeks while daily energy intake and hunger were assessed every 3 days. Test subjects had reductions in body weight (1.5 kg, P < 0.001), body mass index (0.5 kg/m2, P < 0.001) and body fat percentage (0.3%, P < 0.001) versus Controls. NUTRIOSE® supplementation resulted in a lower daily energy intake (3,079 kJ/day, P < 0.001) with group differences noted as early as 3 days. Test subjects reported less hunger across the study period versus Controls ( P < 0.01). NUTRIOSE® supplementation for 12 weeks results in body composition improvements and reduces body weight, energy intake and hunger in overweight men. [ABSTRACT FROM AUTHOR]

This study reports the intact lipids and the phylogenetic compositions of archaea from marine sediments adjacent to or within a region of methane seeps and hydrate mounds in the Mississippi Canyon (MC) Block 118 in the Gulf of Mexico. An aliquot of lyophilized sediment (∼5 g) was extracted for total lipids. Fractions of the glycerol dialkyl glycerol tetraethers (GDGTs) were obtained through column fractionation and determined using liquid-chromatography-mass spectrometry. DNA was extracted from a different aliquot of the sample (∼7 g) that was kept at -80°C. GDGTs showed distinct patterns between non-hydrate and hydrate-impacted samples, suggesting dramatically different archaeal communities caused by the presence of gas hydrates or cold seeps. Clone libraries of 16S rRNA genes were constructed to provide a phylogenetic explanation of the archaeal populations possibly causing the variation in lipid profiles. In contrast to the non-thermophilic crenarchaeota-dominant species in the normal marine sediment, the hydrate-impacted samples showed the predominance of ANME-1 subgroups with Thermoplasmatales being secondarily abundant; both of them are known to produce tetraether lipids and may be responsible for the enhanced archaeal lipids in the hydrate samples. MC 118 is designed to be a seafloor observatory in the Gulf of Mexico and our study represents the initial efforts in characterizing archaeal populations and their role in carbon cycle at this location. [ABSTRACT FROM AUTHOR]

Water vapor permeation through a silicone rubber-PSF (polysulfone) resistance composite membrane was studied. The resistance of the asymmetric composite membrane to the permeation of nitrogen, hydrogen, and water vapor is discussed on the basis of a serial resistance model. Compared with nitrogen and hydrogen, the resistance to water vapor is not attributable to the skin layer but is mainly due to the support layer of high water vapor permeability. The water vapor permeability decreases considerably with the increase of support layer resistance; the effect was greater when a relatively high vacuum was applied to the permeate gas side of the membrane. This result was also verified by the experiments of gas and vapor permeation through the composite membrane. In addition, the effects of the membrane structure on the water vapor permeability, as well as on the resistance of the support layer, were also investigated. The membrane dehumidification process was used because it increased the porosity, the pore size of the support layer, and the thickness of the skin layer. [ABSTRACT FROM AUTHOR]