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In this paper the problem of momentum and heat transfer in a thin liquid film of power-law fluid on an unsteady stretching surface has been studied. Numerical solutions are obtained for some representative values of the unsteadiness parameter S and the power-law index n for a wide range of the generalized Prandtl number, 0.001 ≤ Pr ≤ 1000. Typical temperature and velocity profiles, the dimensionless film thickness, free-surface temperature, and the surface heat fluxes are presented at selected controlling parameters. The results show that increasing the value of n tends to increase the boundary-layer thickness and broadens the temperature distributions. The free-surface temperature of a shear thinning fluid is larger than that of a Newtonian fluid, but the opposite trend is true for a shear thickening fluid. For small generalized Prandtl numbers, the surface heat flux increases with a decrease in n, but the impacts of n on the heat transfer diminish for Pr greater than a moderate value (approximately 1 ≤ Pr ≤ 10, depending on the magnitude of S).

In this study, we use dimethyloldihydroxyethyleneurea to treat cotton fabrics with various processes by changing the bath concentrations. We find that dry and wet crease recovery angles of the fabrics treated with the pad-dry-high-pressure-steam (HPS) cure process are higher than those for other processes at a given tensile strength retention. Crosslinking length and dry and wet crease recovery angles of the fabrics finished with the pad-dry-HPS-cure process are higher than those for the pad-dry-cure process for a given number of crosslinks per anhydroglucose unit. Additionally, the surface distribution of the crosslinking agent on the fabrics finished with the pad-dry-HPS-cure process is more significant than that for the pad-dry-cure process.

Supplemental Digital Content is available in the text, In Taiwan, colorectal cancer with peritoneal carcinomatosis is considered a terminal condition. We examined the clinical outcomes of cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) treatment for colorectal cancer with peritoneal carcinomatosis in Taiwan. We enrolled patients with colorectal cancer and peritoneal metastasis from Taipei Medical University, Wanfang Hospital between January 1999 and December 2014. Of the enrolled patients, 3 had mucinous-type tumors. In total, we enrolled 31 patients who underwent a total of 33 procedures. Of the 31 patients, 2 received the HIPEC procedure twice. Cytoreductive surgery was performed followed by HIPEC. The hazard ratios of death following cytoreductive surgery and HIPEC were calculated using the Cox proportional hazards model. The 2- and 5-year overall survival rates of these patients following cytoreductive surgery and HIPEC were 57% and 38%, respectively. The completeness of cytoreduction (CC) scores were CC-0, CC-1, CC-2, and CC-3 in 18 (54.5%), 3 (9%), 7 (21.2%), and 5 (15.2%) patients, respectively. The mean peritoneal cancer index (PCI) was 16.20, and the mean postoperative PCI (PPCI) was 4.6. The major risk factors for death in these patients were a total PCI score > 20, total PPCI score > 0, and CC score ≥ 2 (P = 0.022, 0.031, and 0.0001, respectively; log-rank test). Multivariate analysis revealed that the total PPCI score was the strongest predictor of death following cytoreductive surgery and HIPEC in these patients. In Taiwan, performing cytoreductive surgery and administering HIPEC for treating colorectal cancer with peritoneal metastasis are feasible and resulted in long-term survival. In addition, the total PPCI score was related to poor prognosis following cytoreductive surgery and HIPEC in patients with colorectal cancer and peritoneal metastasis.

Dimethyloldihydroxyethyleneurea (DMDHEU) and acrylic acid (AA) were used to synthesize the dimethyloldihydroxyethyleneurea–acrylic acid product (DMDHEU–AA, mole ratios of DMDHEU/AA = 1/0, 1/1, and 1/2, respectively). Cotton fabrics were treated with the various prereacted DMDHEU–AA products by changing resin concentrations in the bath. We found that the dry crease recovery angle (DCRA) and wet crease recovery angle (WCRA) of the treated fabrics increased with the increase of acrylic acid in the prereacted DMDHEU–AA at the same value of resin concentration in the bath, whereas the tensile strength retention (TSR) showed the inverse tendency. For a given value of number of crosslinks per anhydroglucose unit (CL/AGU), the DCRA and WCRA values of the DMDHEU–AA-treated fabrics were higher than those for DMDHEU-treated fabrics. Additionally, agent distribution and the reaction between –COOH of the crosslinking agent and cellulose molecule were also investigated in this study. © 2001 John Wiley & Sons, Inc. J Appl Polym Sci 82: 1580–1586, 2001

The problem of free convective heat transfer from an impermeable vertical plate embedded in a thermally stratified, fluid-saturated porous medium is analyzed for the case of power-law variation in the wall temperature. The non-Darcian effects, such as solid-boundary viscous resistance, high-flow-rate inertia force, near-wall nonuniform porosity distribution and thermal dispersion, have been considered in the present analysis. Due to the variation of porosity in the near wall region, the stagnant thermal conductivity varies accordingly. The present work examines the effects of non-Darcian flow phenomena and thermal stratification on free convective transport and demonstrates the variation in heat transfer prediction based on different flow models. The nonsimilar system of transformed equations is solved using Keller’s Box method. It is shown that the thermal stratification reduces the heat transfer rate from the vertical surface, while a higher value of the wall temperature exponent m increases the heat transfer rate. Also, the non-Darcian and thermal dispersion effects have significant influences on velocity and temperature profiles as well as the local heat transfer rate.

The nonsimilar non-Darcy mixed convection adjacent to a horizontal surface in a saturated porous medium is analyzed. Nonsimilarity solutions are obtained for the case of variable surface temperature in the form T w ( x )= T ∞ + ax n . The analysis is performed for the entire mixed convection regime which is divided into two regions. The first region covers the forced-convection-dominated regime and the second region covers the free-convection-dominated regime. The Darcy–Brinkman–Forchheimer equation is used as the momentum equation, and the effect of near-wall porosity variation is approximated by an exponential function. The effects of thermal dispersion and variable stagnant thermal conductivities are taken into consideration in the energy equation. Velocity and temperature profiles and local Nusselt numbers are presented for different governing parameters. Effects of non-Darcy flow phenomena on the heat transfer characteristics are thoroughly examined.

The problem of non-Darcy mixed convection along a vertical flat plate embedded in a saturated porous medium is analyzed for the case of variable surface heat flux. Based on three different flow models, the influences of non-Darcy flow phenomena on mixed convection from a vertical surface are thoroughly investigated. The wall effect on porosity variation is approximated by an exponential function. The effects of thermal dispersion and variable stagnant thermal conductivity are taken into consideration in the energy equation. The entire regime of mixed convection, including the two limits of pure forced convection and pure free convection, is covered by employing a single nonsimilarity parameter. The resulting nonsimilar system of equations is solved using a finite difference method. Results are presented for temperature and velocity profiles, and local Nusselt number for representative values of different controlling parameters.

This article investigates numerically the heat transfer characteristics of non-Darcy mixed convection over a horizontal flat plate with nonuniform surface heat flux in a porous medium. The surface heat flux is assumed to vary as a power of the axial coordinate measured from the leading edge of the plate. The entire regime of mixed convection (including the two limits of pure forced convection and pure free convection) is divided into two regions, namely the forced convection dominated regime and the free convection dominated regime. The effects of flow inertia force, solid boundary shear, near-wall porosity variation, and thermal dispersion are considered in the present analysis. The Darcy-Brinkman-Forchheimer equation is used to model the motion of fluid through the porous medium, and the porosity variation is approximated by an exponential function. The local Nusselt numbers, valid for the entire mixed convection regime, are presented for representative values of governing parameters.

Objectives: To study the pattern of tuberculosis transmission in Taiwan. Methods: An insertion sequence IS 6110 -based restriction fragment length polymorphism (RFLP) analysis of Mycobacterium tuberculosis isolates was conducted. Results: Among 85 patients with culture-confirmed tuberculosis diagnosed between August 1993 and March 1994, 79 (93%) had isolates with unique RFLP patterns, whereas 6 (7%) had isolates that belonged to three clusters of identical RFLP patterns. Two strains in one cluster were isolated from patients who lived in the same small village. The average age of the patients was 54 years, and more than 40% had an underlying medical problem. The high degree of diversity of the RFLP patterns, and the demographic and clinical characteristics of the patients suggest that, in Taiwan, a large proportion of newly diagnosed tuberculosis cases are attributable to reactivation of an infection acquired in the remote past. These observations contrast with those in communities with a high prevalence of human immunodeficiency virus (HIV) infections, where a large proportion of new tuberculosis cases may be attributable to recent infections. Conclusions: The findings suggest that the distribution of M. tuberculosis with identical RFLP patterns (representing recent transmissions) may be greatly influenced by the prevalence of HIV infections in the community. In addition, the steady decline in the incidence of tuberculosis in Taiwan, despite its relatively high incidence, suggests that the trend in disease incidence may be influenced by the prevalence of cluster strains in the community.

An analysis is performed for mixed convective flow through a fluid-saturated porous medium adjacent to a vertical surface with the heating condition of power-law variation in the wall temperature. The entire mixed convection regime is covered by the single parameter χ = [1+( Ra x / Pe x ) 0.5 ] −1 from the pure forced convection limit ( χ = 1) to the pure free convection limit ( χ = 0). In modeling the flow through porous media, non-Darcy effects such as high-flow-rate inertia forces, no-slip boundary condition, near-wall porosity variation and thermal dispersion are taken into consideration. Because of the porosity variation in the near wall region, the stagnant thermal conductivity also varies accordingly. The aims of the present work are to examine the effects of non-Darcian flow phenomena on mixed convective transport and to demonstrate the variation in heat transfer predictions based on different flow models. A finite difference scheme was used to solve the transformed system of equations. Numerical results show that non Darcian and thermal dispersion effects have significant influences on velocity profiles, temperature profiles and heat transfer rates from the vertical surface.

This study investigates a vertical plate fin cooled by an oncoming turbulent flow. The base temperature of the fin varies periodically and the local heat transfer coefficient of the fin surface is determined by a conjugate convection-conduction analysis rather than arbitrarily specified. The heat conduction problem within the fin coupled with the boundary layer flow problem outside the fin surface are solved simultaneously. The calculated results include the effects of the conjugate convection-conduction parameter Nc as well as the oscillation amplitude and frequency of the base temperature on the fin cooling behavior.

To investigate the outcomes of the selective neoadjuvant concurrent chemoradiotherapy (CCRT) in lower 3rd rectal cancer patients in different groups (with or without neoadjuvant CCRT), especially in survival rate, local recurrence rate, and sphincter preservation rate. From January 1999 to December 2012, 69 consecutive patients who had histologically proven adenocarcinoma of lower 3rd rectum, defined preoperatively as lower tumor margin within 7 cm from the anal verge as measured by rigid sigmoidoscopy, received total mesorectum excision (TME). Our inclusion criteria of neoadjuvant CCRT are lower 3rd rectal cancer, stage II/III, and large (diameter >5 cm or >1/2 of circumference). Neoadjuvant concurrent CCRT had begun to apply lower 3rd rectal cancer patients or not. The radiation techniques of neoadjuvant CCRT for lower 3rd rectal cancer patients were all conventional fraction intensity modulated radiotherapy (IMRT) and concurrent fluoropyrimidine chemotherapy. Five-year overall survival rate, disease-free survival rate, and local recurrence rate for lower 3rd rectal cancer patients in group I were 51%, 45%, and 25%, respectively. On the contrary, 5-year overall survival rate, disease-free survival rate, and local recurrence rate for lower rectal cancer patients in group II were 70%, 70%, and 3%, respectively. The 5-year sphincter sparing rate was increased from 38.2% to 100% after the beginning of neoadjuvant CCRT. Analyzing local recurrence, overall survival rate, disease-specific survival rate, and sphincter sparing rate in group II were statistically significant superior to group I. Five-year overall survival rate, disease-free survival rate, and sphincter sparing rate for lower 3rd rectal cancer patients were improved after the addition of neoadjuvant CCRT. No unacceptable toxicity was noted after conventional fraction IMRT and concurrent fluoropyrimidine chemotherapy. Our study showed neoadjuvant CCRT could be valuable for lower 3rd rectal cancer patients.

The influence of non-Darcian flow phenomena on the natural convection heat transfer from a vertical plate fin embedded in a porous medium was studied. With the thin-fin approximation for the plate fin and the non-Darcy flow model for the convective fluid, numerical solutions were generated to demonstrate the importance of non-Darcian effects on conjugate natural convection flow adjacent to the fin. These effects, which are often involved in convective transport of fluid through porous media, include high-flow-rate inertial force, solid-boundary viscous resistance, nonuniform porosity distribution, and thermal dispersion. The present work aims to investigate these effects on the fin heat-transfer characteristics such as fin temperature distributions, the local heat transfer coefficient, the local heat flux, and the overall rate of heat transfer.

This work presents an analysis of microfluidic flow introduced by mixed electrokinetic force and pressure gradient. Analytical solutions are presented for the case of constant surface heat flux, taking the Joule heating effect into account. The present problem is governed by two scale ratios and the dimensionless source term. The two important ratios are the length scale ratio e (the ratio of Debye length to the tube radius R) and the velocity scale ratio Γ (the ratio of the pressuredriven velocity scale for Poiseuille flow to Helmholtz-Smoluchowski velocity for electroosmotic flow). For mixed electroosmotic and pressure-driven flow, the resulting velocity profile is the superimposed effect of both electroosmotic and Poiseuille flow phenomena. It is found that the velocity profile decreases as e increases and the normalized temperature profiles across the tube increases monotonously form the core to the wall. The maximum dimensionless temperature is observed at the wall and the wall temperature increases with increasing Joule heating. Also, the temperature is increased with increasing the value of e . The fully developed Nusselt number takes the maximum value at the limiting case of e → 0 , and then decreases with increasing e . Moreover, the Nusselt number decreases with Γ and then goes asymptotically to the limit of Poiseuille flow as Γ → ∞ , where the flow is dominated by the pressure force.

A theoretical analysis is presented to explore the transport characteristics of electro-osmotic flow and associated heat transfer of non-Newtonian power-law fluids in a parallel plate microchannel. The formulation shows that the key parameters governing the current problem include the flow behavior index, the length scale ratio (ratio of Debye length to half channel height), and the Joule heating parameter (ratio of Joule heating to surface heat flux). Analytical expressions are presented for velocity and temperature profiles, the friction coefficient, and the fully developed Nusselt number. In particular, closed-form solutions are obtained for several special values of the flow behavior index. The results reveal that reducing the length scale ratio tends to increase the friction coefficient, and the friction coefficient approaches infinite for slug flow. The increase in the friction coefficient due to increasing the flow behavior index is more noticeable for a smaller length scale ratio. For surface heating, increasing the flow behavior index amplifies the temperature difference between the wall and the fluid, and thus the temperature distribution broadens; while the opposite trend is observed for surface cooling with sufficiently large Joule heating parameter with negative sign. Depending on the value of Joule heating parameter, the fully developed Nusselt number can be either increased or decreased by increasing the flow behavior index and/or the length scale ratio. The effect of flow behavior index on the Nusselt number vanishes as the length scale ratio approaches zero (the limiting case for slug flow).

To study the association of waist to height ratio (WHtR) and elevated blood pressure (BP) in children.Cross-sectional study.Six elementary schools in Taipei, Taiwan.All children aged 7 years at first grade.We measured anthropometrics and BP during the regular health examinations among children.Elevated BP in children was defined as an average systolic BP or diastolic BP greater than or equal to the gender, age, and height-percentile-specific 95th percentile BP value.Among 2,334 eligible school children, the averages of systolic BP and diastolic BP increased with quartiles of WHtR. The prevalence of elevated BP in children among the first quartile of WHtR was 8.8% and increased to 31.2% among the fourth quartile of WHtR (P0.0001). Children among the first quartile of WHtR being reference, the adjusted odds ratio of elevated BP for children among the fourth quartile of WHtR was 3.10. The odds ratio of elevated BP with per 0.01 increase of WHtR was 1.11.WHtR, simple to measure, is an important factor associated with elevated BP in children.

Conjugate mixed convection-conduction heat transfer from a vertical, cylindrical fin embedded in a saturated, high-porosity, porous medium is analyzed. The effects of both boundary and inertia forces were taken into account. The numerical solutions of the problem are obtained by a local nonsimilarity method. Results were obtained for the surface curvature parameter λ = 1, 2, and 4 and other parameters in the range of 0 ≤ Ncc ≤ 2.0 and 0 ≤ Ω ≤ 2.0. The heat transfer coefficients are found to follow trends similar to those of the classical fluids. Both boundary and inertia effects decrease the heat transfer rate and become more significant for mixed convection flow, especially downstream and at large values of N Ncc The total heat transfer rates are higher for lower values of λ, that is, for larger fin radius r No

This paper presents a numerical study on the heat transfer characteristics and cooling performance of a microchannel heat sink with water-γAl2 O3 nanofluids having different nanoparticle volume fraction. In view of the small dimensions of the microstructures, the microchannel heat sink is modeled as a fluid-saturated porous medium in the simulation. The Forchheimer-Brinkman-extended Darcy equation is used to describe the fluid flow and the two-equation model with thermal dispersion is utilized for heat transfer. Typical results for the temperature distributions of the fin and fluid phase are presented for various values of the inertial force parameter. It is found that the fin temperature distribution is practically not sensitive to the inertial effect, while the fluid temperature distribution and the total thermal resistance change significantly due to the inertial force effect. In general, the effect of fluid inertia is to reduce the total thermal resistance and the temperature difference between the fin and the fluid phase. The total thermal resistances obtained from the present model with inertial effect match well with the available experimental results, whereas the thermal resistance is overestimated as the inertial effect is neglected.Copyright © 2009 by ASME

This study investigates convective transport phenomena of combined electro-osmotic and pressure-driven flow in a microchannel subject to constant surface heat flux, with Joule heating effect taken into account. The governing system of equations includes the electric potential field, flow field, and energy equations. Analytical solutions are obtained for constant fluid properties, while numerical solutions are presented for variable fluid properties. For constant properties, the problem is found to be governed by three ratios: the length scale ratio (the ratio of Debye length to half channel height), the velocity scale ratio (the ratio of pressure-driven velocity to electro-osmotic velocity), and the ratio of Joule heating to surface heat flux. A small length scale ratio corresponds to a microchannel, while finite length scale ratio represents a nanochannel. For electro-osmotic flow only, the momentum transport is solely a function of the length scale ratio. For combined electro-osmotic and pressure-driven flow, the velocity profile and therefore the friction factor depend on both the length scale ratio and the velocity scale ratio. Assuming a thermally fully developed flow, analytical expressions for the normalized temperature profile and Nusselt number are developed. The representative results for the friction factor, normalized temperature profile, and Nusselt number are illustrated for some typical values of the three ratios. For purely electro-osmotic flow, it is found that the Nusselt number increases with decreasing ε, approaching the value for slug flow as the length scale ratio approaches zero. For mixed flow with a given length scale ratio, the results show that the Nusselt number decreases with the velocity scale ratio, approaching the classical Poiseuille flow as the velocity scale ratio approaches infinite. When the effects of variable fluid properties are included in the analysis, numerical solutions are generated to explore the influence of thermal conductivity and viscosity variations with local temperature on the hydrodynamic and thermal characteristics of the fluid. These temperature-dependent property variations would initially develop pressure-driven flow, and correspondingly the dimensionless velocity and volume flow rate increase to account for such variations. The friction factor reduces considerably with viscosity variation, while the Nusselt number increases gently. Although the influence of thermal conductivity variation on the hydrodynamic characteristics is not impressive, it has certain impact on the heat transfer results; more specifically, increasing the conductivity variation will produce a sensible increase in Nusselt number but a small decrease in the normalized temperature.

The analysis is performed for a mixed convective boundary layer flow in a fluid-saturated porous medium near a vertical surface. In modelling the flow in the porous medium the non-Darcian effects such as the flow inertia, no-slip boundary conditions, nonuniform porosity, and thermal dispersion are taken into account. Because of the porosity variation in the near-wall region, the stagnant thermal conductivity also varies accordingly. These effects have a significant influence on velocity and temperature profiles and heat transfer rate from the flat plate. This work examines these effects on mixed convective transport and demonstrates the variation in heat transfer predictions based on different flow models. The present study also discusses the dependence of fluid flow and heat transfer characteristics on the problem parameters.

Mixed convection flow about a vertical plate fin embedded in a variable porosity medium, based on the conjugate convection-conduction theory, is analyzed. The non-Darcian effects, which include the no-slip and inertial effects, and nonuniform porosity condition are considered. Inclusion of these effects significantly alters the heat transfer from those predicted by using the Darcy flow model. For comparison, computations of heat transfer characteristics based on three velocity models, i.e., the Darcy-Brinkman-Ergun model with uniform and nonuniform porosities and the Darcy flow model, are performed. The results show that due to the near-wall porosity variation, the heat transfer rate is greatly increased. The effects of the conjugate convection-conduction parameter and the buoyancy force parameter on fin temperature distribution, the local heat transfer coefficient, local heat flux, overall heat transfer rate, and fin efficiency are illustrated.

Previous report showed that epidermal growth factor (EGF) promotes tumor progression. Several studies demonstrated that growth factors can induce heme oxygenase (HO)-1 expression, protect against cellular injury and cancer cell proliferation. In this study, we investigated the involvement of the c-Src, NADPH oxidase, reactive oxygen species (ROS), PI3K/Akt, and NF-κB signaling pathways in EGF-induced HO-1 expression in human HT-29 colon cancer cells. Treatment of HT-29 cells with EGF caused HO-1 to be expressed in concentration- and time-dependent manners. Treatment of HT-29 cells with AG1478 (an EGF receptor (EGFR) inhibitor), small interfering RNA of EGFR (EGFR siRNA), a dominant negative mutant of c-Src (c-Src DN), DPI (an NADPH oxidase inhibitor), glutathione (an ROS inhibitor), LY294002 (a PI3K inhibitor), and an Akt DN inhibited EGF-induced HO-1 expression. Stimulation of cells with EGF caused an increase in c-Src phosphorylation at Tyr406 in a time-dependent manner. Treatment of HT-29 cells with EGF induced an increase in p47(phox) translocation from the cytosol to membranes. The EGF-induced ROS production was inhibited by DPI. Stimulation of cells with EGF resulted in an increase in Akt phosphorylation at Ser473, which was inhibited by c-Src DN, DPI, and LY 294002. Moreover, treatment of HT-29 cells with a dominant negative mutant of IκB (IκBαM) inhibited EGF-induced HO-1 expression. Stimulation of cells with EGF induced p65 translocation from the cytosol to nuclei. Treatment of HT-29 cells with EGF induced an increase in κB-luciferase activity, which was inhibited by a c-Src DN, LY 294002, and an Akt DN. Furthermore, EGF-induced colon cancer cell proliferation was inhibited by Sn(IV)protoporphyrin-IX (snPP, an HO-1 inhibitor). Taken together, these results suggest that the c-Src, NADPH oxidase, PI3K, and Akt signaling pathways play important roles in EGF-induced NF-κB activation and HO-1 expression in HT-29 cells. Moreover, overexpression of HO-1 mediates EGF-induced colon cancer cell proliferation.

We have determined the physical properties of cotton fabrics treated with di methyloldimethyldihydroxyethyleneurea in the presence of aluminum salts, tartaric acid, or their mixtures under various curing conditions. We have also investigated the kinetics of the cellulose-DMDMDHEU reaction catalyzed by 0.015 M of various ratios of aluminum sulfate and tartaric acid mixtures in the 50 to 120°C temperature range. We calculated the specific reaction rate constant and activation parameters for the reaction, and found that the transition state complex at lower curing temperatures (

The extended Reynolds equation is solved numerically by using the finite difference method to determine the effects of the fluid film inertia forces on the performance of finite journal bearings. Data concerning the operating characteristics of finite journal bearings are provided as a function of length-to-diameter ratio, clearance ratio, reduced Reynolds' number and eccentricity ratio. The pressure distributions are also presented in graphical form. Numerical results reveal that the influence of inertia forces on loadcarrying capacity and attitude angle in finite journal bearings is small at moderate values of the reduced Reynolds number. The principal effect of inertia forces is a significant increase in the side flow rate.