• Tuberculosis and Respiratory Diseases
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• v.67 no.5
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• pp.402-408
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• 2009

Background: Pre-B-cell colony enhancing factor (PBEF) has been suggested as a novel biomarker in sepsis and acute lung injury. We measured the PBEF in bronchoalveolar lavage (BAL) fluid of acute critically ill patients with lung infiltrates in order to evaluate the clinical utility of measuring PBEF in BAL fluid. Methods: BAL fluid was collected by bronchoscope from 185 adult patients with lung infiltrates. An enzyme-linked immunosorbent assay was then performed on the collected fluids to measure the PBEF. Results: Mean patient age was 59.9 ${\pm}$14.5 years and 63.8% of patients were males. The mean concentration of PBEF in BAL fluid was 17.5 ${\pm}$88.3 ng/mL, and patients with more than 9 ng/mL of PBEF concentration (n=26, 14.1%) had higher Acute Physiology and Chronic Health Evaluation (APACHE) II and Sequential Organ Failure Assessment (SOFA) scores on the BAL exam day. However, there were no significant differences in clinical characteristics between survivors and non-survivors. In patients with leukocytosis (n=93) seen on the BAL exam day, the linear regression analysis revealed a significant, positive relationship between PBEF and APACHE II ($r^2$=0.06), SOFA score ($r^2$=0.08), Clinical Pulmonary Infection Score ($r^2$=0.05), and plateau pressure in patients on ventilators ($r^2$=0.07) (p<0.05, respectively). In addition, multivariate regression analysis with PBEF as a dependent variable showed that the plateau pressure ($r^2$=0.177, p<0.05) was correlated positively with PBEF. Conclusion: The PBEF level in the BAL fluid may be a useful, new biomarker for predicting the severity of illness and ventilator-induced lung injury in critically ill patients with lung infiltates and leukocytosis.

• Journal of the Korean Geotechnical Society
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• v.35 no.4
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• pp.37-42
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• 2019

Hydrate dissociation is required to produce methane, which generates both water and methane. Thus, multiphase fluid flow and desalination are expected during methane production, which causes the fine migration and clogging in pores. The goal of this study is to explore the effects of both multiphase fluid flow and desalination on the migration and clogging of kaolin particles as typical fines. The results are as follows : (1) the larger the pore size is, the more mounting the critical clogging concentration is, (2) kaolin particles are more easily clustering and clogging in deionized water than salty water, and (3) the critical clogging concentration of kaolin in multiphase fluid flow is lower than in singlephase fluid flow. Therefore, clustering and clogging of kaolin within pore occur easily due to desalination and multiphase fluid flow when methane is produced from hydrates, and the efficiency of methane production is expected to decrease due to the degradation of permeability coefficient.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.2
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• pp.50-57
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• 2003

This paper presents the experimental results to verify the atomization characteristics and environmental impact of cutting fluid. Even though cutting fluid improves the productivity through the cooling, Lubricating effects, environmental impact due to cutting fluid usage is also increased on factory shop floor Cutting fluid's aerosol via atomization process can be affected human health risk such as lung cancer and skin diseases. Experimental results show that the generated fine aerosol which particle size less than 10 micron appears near working tone under typical operational conditions. The aerosol concentration also exceeds NIOSH regulations. This research can be provided a basis of environmental impact analysis fur environmental consciousness.

• Journal of applied mathematics & informatics
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• v.41 no.5
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• pp.1085-1102
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• 2023

In this study the magneto hydrodynamic (MHD) micro polar fluid flow of a viscous incompressible fluid past a porous medium in the presence of chemical reaction is considered. This work is devoted to investigate the Soret effect and Electromagnetic radiation effect and analyze analytically. In the energy equation the applied magnetic field strength and in the concentration equation the Soret effect are incorporated. The basic PDE (partial differential equations) are reduced to ODE (ordinary differential equations) using non dimensional variables. Then the analytical solution of the dimensionless equations are found using perturbation technique. The features of the fluid flow parameters are analyzed, discussed and explained graphically. The graphical solutions are found using MATLAB R2019b. Skin friction coefficient at the wall, Couple stress coefficient at the plate and the local surface heat flux are also thoroughly examined. Overall, this study sheds light on the complex interplay between physical parameters in the behavior of MHD micro-polar fluid past a porous medium in the presence of chemical reaction.

• Clinical and Experimental Reproductive Medicine
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• v.27 no.2
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• pp.151-157
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• 2000

Objective: The purpose of this study was to evaluate the effect of polycystic ovarian follicular fluid on sperm motility in human in vitro fertilization (IVF). Methods: From May, 1998 to July, 1999, 55 patients who complained of infertility were involved in this study. We obtained ovarian follicular fluids from the patients by ultrasono-guided aspiration. Subjects were divided into two groups. 20 patients who had polycystic ovarian disease were belong to study group, and 25 patients who had normal ovarian follicular fluid were belong to control group. The follicular fluid dilution was done with Ham's fluid as 10%, 20%, 50%, 100%. The sperm motility was analyzed by CASA at 6hr and 12hr after incubation in follicular fluids. Results: The levels of average path velocity (VAP) in all concentration fluid didn't show significant difference between study and control group. The other parameters including curvilinear velocity (VCL), amplitude of lateral head displacement (ALH), and linerity (LIN) were didn't show any significant difference between both groups. Conclusion: PCOD fluid had seemed to have an adverse effect on the sperm biological function. But, this study showed that PCOD fluid had no different effect on sperm motility with normal follicular fluid.

• Asian-Australasian Journal of Animal Sciences
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• v.2 no.4
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• pp.583-590
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• 1989

Increasing levels of ammonia-N in the rumen fluid used for in vitro incubation were achieved by supplementation of the ration of the donor cows with urea and by addition of urea either with or without glucose to the rumen fluid after collection. The ration of the donor animals consisted of wheat straw (80%) and maize silage (20%). During the second half of the experiment the basal ration was supplemented with a mineral mixture. Wheat straw, Guinea grass and two rice straw varieties were incubated with the various kinds of rumen fluid. Parameters studied were: solubility, apparent organic matter disappearance after 48 hours of incubation ($OMD_{48}$), rate of organic matter degradation from 0 to 24 hours of incubation ($k_1$) and from 24 to 95 hours ($k_2$). The concentration of ammonia-N in the rumen fluid at which 95% of the maximal $OMD_{48}$ and k1 were reached (88.2 and 100.0 mg/l) were independent of the feed. With regard to the $k_2$ the required ammonia-N concentration to reach 95% of the maximal $k_2$ differed per feed. Mineral supplementation increased the OMD48 and $k_1$, but not the solubility and $k_2$. Glucose addition in combination with urea had no beneficial effect compared to urea supplementation alone.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.2
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• pp.22-27
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• 2017

During the water treatment process for household water supply, a reservoir is the last place the water is stored before being supplied to users, and the duration of the water's stay is an important factor that affects its safety. This may cause the concentration of the residual chlorine disinfectant to increase and thus lower the water's quality. The concentration and discharge efficiency of residual chlorine must be verified and managed, because these are key factors that affect the reservoir's performance. Because the actual verification test for analyzing the efficiency of a reservoir and the disinfectant's dilution capacity is difficult, simulations are generally conducted using the computational fluid analysis method. However, the simulation results require validation with experiments. The error and drainage efficiency were analyzed in this study by comparing and analyzing the actual tracer test and simulation so that the actual test for a hexagonal drainage can be replaced by the computational fluid analysis method. Based on the results of the efficiency analysis, the hexagonal reservoir was found to be appropriate, and the simulation's reliability was verified with a tracer test.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.31 no.3
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• pp.353-358
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• 1998

Experiments were performed to find out the physico-chemical properties of milt, and morphological changes of cryopreserved spermatozoa in tiger puffer, Takifugu rubripes. The average number of sperm and spermatocrit in milt stripped were $9.81{\pm}0.34{\times}10^{10}/m{\ell}$ and $97.8{\pm}0.8$, respectively. While total lipid concentration from seminal fluid was higher than that from sperm, total protein concentration from sperm was higher than that from seminal fluid, Na and K concentrations in sperm and those in seminal fluid were similar each other, However, glucose from sperm and seminal fluid were not detectable. Spermatozoon of tiger puffer was consisted of head, middle Piece and tail. Size of head showing horseshoe shape was $0.65{\pm}0.10{\mu}m$ in diameter and $1.35{\pm}0.30{\mu}m$ in length. The head fully containing chromatin did not have acrosome. Mitochondrion in middle piece was $0.2{\mu}m$ in average diameter and flagellum showed 9+2 structure. A few of cryopreserved spermatozoa showed morphologically loose or swollen plasma membranes.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• v.20 no.4
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• pp.333-354
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• 2016

The present investigation deals, heat and mass transfer characteristics with the effect of slip on the hydromagnetic pulsatile flow through a parallel plate channel filled with saturated porous medium. Based on the pulsatile flow nature, exact solution of the governing equations for the fluid velocity, temperature and concentration are obtained by using two term perturbation technique subject to physically appropriate boundary conditions. The expressions of skin friction, Nusselt number and Sherwood number are also derived. The numerical values of the fluid velocity, temperature and concentration are displayed graphically whereas those of shear stress, rate of heat transfer and rate of mass transfer at the plate are presented in tabular form for various values of pertinent flow parameters. By increasing the slip parameter at the cold wall the velocity increases whereas the effect is totally reversed in the case of shear stress at the cold wall.

• Transactions of the Korean hydrogen and new energy society
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• v.22 no.1
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• pp.109-117
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• 2011

Since the thermal performance of cycles for use of low-temperature source is low if a pure working fluid is used, the cycles using ammonia-water binary mixture as a working fluid has attracted much attention over past two decades. Recently, several commercial power plants using Kalina cycles have been built and being operated successfully. In this work thermodynamic performance of Kalina cycles using ammonia-water mixture as a working fluid is investigated for the purpose of extracting maximum power from low-temperature energy source. Special attention is paid to the effect of system parameters such as concentration of ammonia and turbine inlet pressure on the characteristics of the system. Results show that the system performance is influenced sensitively by the ammonia concentration, and the role of the performance of heat exchangers is crucial.