• Title/Summary/Keyword: Erickson

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Performance Analysis of Carbon Canister for Reducing Evaporative Emissions in a Gasoline Automotive Engine

  • Chung, Yon-Jong;Cho, Gyu-Sang;Erickson, Paul A.;Han, Sung-Bin
    • Journal of Energy Engineering
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    • v.17 no.2
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    • pp.47-53
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    • 2008
  • The objective of this paper is to clarify the flow characteristic, velocity distribution, pressure loss, and other such fundamental data for the canister during loading and purging. The amount of gas that is loaded increases as the loading rate is decreased and the time increased, and the purging improves as the purge rate is increased. The hydrocarbons that are purged initially have a high concentration, and a large amount is purged. During loading and purging, the temperature initially increases and decreases drastically due to heat generation and heat loss.

Conjugated Linoleic Acid Reduction of Vascular Endothelial Growth Factor Expression in Murine Mammary Tumor Cells through Alteration of Prostaglandin E2

  • Kim, Jung-Hyun;Hubbard, Neil E.;Lim, Debora;Erickson, Kent L.
    • Preventive Nutrition and Food Science
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    • v.11 no.1
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    • pp.1-5
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    • 2006
  • Conjugated linoleic acid (CLA) is a group of positional and geometric isomers of linoleic acid that have been used to reduce the incidence, growth and metastasis of breast, colon, prostate and gastric cancer in animals. CLA could reduce tumor growth by altering angiogenesis; a process requiring associated angiogenic factors such as vascular endothelial growth factor (VEGF). In this study, we determined whether CLA could modulate the expression of VEGF in murine mammary tumor cells and adipocytes. The c9, t11-CLA isomer reduced VEGF transcripts and protein when mammary tumor cells were stimulated with PMA. That isomer also reduced VEGF expression in un stimulated mouse 3T3-L1 adipocytes. Since VEGF can be regulated by cyclooxygenase-2 (COX-2), we determined whether CLA could alter COX-2 enzyme expression and $PGE_2$ production. The c9, t11-CLA isomer reduced not only COX-2 enzyme expression but also $PGE_2$ production. Thus, c9, t11-CLA could modulate neovascularization by alteration of VEGF expression from mammary tumor cells and adipocytes by reducing COX-2 metabolites.

INTERACTIVE INFLUENCE OF DIETARY PROTEIN AND LIPID IN LACTATION

  • Park, C.S.;Choi, Y.J.;Fisher, G.R.;Erickson, G.M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.1 no.1
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    • pp.7-12
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    • 1988
  • Twenty cows, by order of calving, were used in a completely randomized $2{\times}2$ factorial experiment. Variables were tow protein levels (14 and 18% crude protein) and concentration of fat (2 and 6% ether extract) in diets. Fat addition, via unprocessed whole sunflower seed, insured forage utilization in diets to meet energy requirement of cows. A total of 36 wks of lactation was subdivided into three 12-wk stages of lactation. Net energy lactation was set at 1.72, 1.57 and 1.42 Mcal/kg for each stage. Higher protein diets improved the efficiency of energy (FCM/net energy intake) which was particularly noted for diets containing high fat (85.7%). However, diets with low protein-high fat resulted in the lowest efficiency (67.7%). No difference in milk yield and butterfat was due to different levels and combinations of protein and lipid in diets. High protein diets depressed blood cholesterol and glucose compared to low-protein counterparts. Relative decline in milk production was slower for lower fat diets than for higher fat groups, especially mid to later stage of lactation. Results of this experiment tend to support our thesis on the synergistic effect of dietary protein and energy (lipid) upon efficiency of lactation.

A Membrane-Array Method to Detect Specific Human Intestinal Bacteria in Fecal Samples Using Reverse Transcriptase-PCR and Chemiluminescence

  • KIM PYOUNG IL;ERICKSON BRUCE D;CERNIGLIA CARL E.
    • Journal of Microbiology and Biotechnology
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    • v.15 no.2
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    • pp.310-320
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    • 2005
  • A membrane-based oligonucleotide array was used to detect predominant bacterial species in human fecal samples. Digoxygenin-labeled 16S rDNA probes were generated by PCR from DNA that had been extracted from fecal samples or slurries. These probes were hybridized to an array of 120 oligonucleotides with sequences specific for 40 different bacterial species commonly found in human feces, followed by color development using an alkaline phosphatase-conjugated antibody and NBT /BCIP. Twenty of the species were detected by this method, but E. coli, which was present at $\~$1 $\times 10$^5$ CFU per gram feces, was not detected. To improve the sensitivity of this assay, reverse transcriptase-PCR was used to generate probes from RNA extracted from fecal cultures. Coupled with a chemiluminescence detection method, this approach lowered the detection limit for E. coli from $\~1$ $\times 10$^6$ to ${\leq}$ 1 $\times 10$^5$ These results indicate that the membrane-array method with reverse transcriptase-PCR and chemiluminescence detection can simultaneously identify bacterial species present in fecal samples at cell concentrations as low as${\leq}$ 1 $\times 10$^5$ CFU per gram.

Improvement of Electrode Structure of FFS Mode LCD for Obtaining High Transmittance (FFS모드 LCD의 투과율 향상을 위한 전극 구조 개선)

  • Kim, Bong-Sik;Oh, Hyun-Min;Park, Woo-Sang
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.24 no.4
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    • pp.309-313
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    • 2011
  • In this study, we proposed a novel electrode structure for the fringe field switching (FFS) mode LCD and performed a three-dimensional computer simulation to calculate the optical transmittance for the new structure. In the simulation Erickson-leslie equation and Berreman $4{\times}4$ matrix were used for obtaining the director distribution profiles of liquid crystal molecules and the electro-optical characteristics, respectively. Considering the complexity of the motional equation of the liquid crystal molecules, FDM (finite difference method) was used as a numerical method. From the results, We revealed that the light transmission of the newly designed pixel structure is expended to the edge of the pixel electrode. We also confirmed that the light transmittance increased more than 13% compared to that of the conventional electrode structure.

The Characteristics of Heating Performance on Small Sized Ammonia Absorption System (소형 암모니아 흡수식 냉난방기의 냉방성능 특성)

  • Jin, Byoung-Ju;Oh, Seung-Taek;Yoon, Jung-In;Hwang, Jun-Hyeon;Jin, Sim-Won;Kyung, Ick-Soo;Erickson, Donald C
    • Proceedings of the SAREK Conference
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    • 2008.11a
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    • pp.198-202
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    • 2008
  • Refrigeration plants using absorption principles have been around for many years with initial development taking place over 100 years ago. Although the majority of absorption cycles are based on water-LiBr cycle, many applications exist where ammonia-water can be used, especially where lower temperatures are desirable. In both systems water is used as working fluid, but in quite different ways: as a solvent for the ammonia system, and as refrigerant for the lithium bromide system. This explains that the lithium bromide absorption system is strictly limited to evaporation temperatures above $0^{\circ}C$. The main industrial applications for refrigeration are in the temperature range below $0^{\circ}C$, the field for the binary system ammonia-water.

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Theoretical Analyses of Autothermal Reforming Methanol for Use in Fuel Cell

  • Wang Hak-Min;Choi Kap-Seung;Kang Il-Hwan;Kim Hyung-Man;Erickson Paul A.
    • Journal of Mechanical Science and Technology
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    • v.20 no.6
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    • pp.864-873
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    • 2006
  • As fuel cells approach commercialization, hydrogen production becomes a critical step in the overall energy conversion pathway. Reforming is a process that produces a hydrogen-rich gas from hydrocarbon fuels. Hydrogen production via autothermal reforming (ATR) is particularly attractive for applications that demand a quick start-up and response time in a compact size. However, further research is required to optimize the performance of autothermal reformers and accurate models of reactor performance must be developed and validated. The design includes the requirement of accommodating a wide range of experimental set ups. Factors considered in the design of the reformer are capability to use multiple fuels, ability to vary stoichiometry, precise temperature and pressure control, implementation of enhancement methods, capability to implement variable catalyst positions and catalyst arrangement, ability to monitor and change reactant mixing, and proper implementation of data acquisition. A model of the system was first developed in order to calculate flowrates, heating, space velocity, and other important parameters needed to select the hardware that comprises the reformer. Predicted performance will be compared to actual data once the reformer construction is completed. This comparison will quantify the accuracy of the model and should point to areas where further model development is required. The end result will be a research tool that allows engineers to optimize hydrogen production via autothermal reformation.

Fatty Acid Modulation of Atherosclerosis by Peroxisome Proliferator- Activated Receptors

  • Erickson, Kent L.;Hubbard, Neil E.;Meinecke, Lynette M.
    • Preventive Nutrition and Food Science
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    • v.7 no.4
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    • pp.454-460
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    • 2002
  • While atherosclerosis is a major killer, there is now concern that mortality from the disease will increase due to the rising incidence of type II diabetes. Because diet can potentially influence both diseases, it is important to elucidate the role of diet in the progression of atherosclerosis. In addition, the mechanisms involved in dietary-related alterations of the disease need to be defined to guide public health recommendations to reduce athero-sclerosis incidence and limiting unwanted side effects. Since diet is thought to play a role in atherosclerosis even without added complications due to type II diabetes, reducing the incidence of that metabolic disease will not be enough. While evidence is increasing that high intake of carbohydrate can lead to type II diabetes and atherosclerosis, the preponderance of existing evidence indicates that intake of specific fats as a major dietary causal factor. It has recently been hypothesized that a dietary fat link to atherosclerosis may depend partly on the activity of a transcriptional regulator, the peroxisome proliferator activated receptors (PPAR). Thusfar, PPAR $\alpha$, $\beta$/$\delta$ and ${\gamma}$, have been shown to play a major role in metabolism, inflammation, and cancer. Furthermore, PPAR may regulate specific processes associated with atherosclerosis such as triglyceride and low density lipoprotein (LDL) metabolism; the reverse cholesterol transport pathway; lipid accumulation within plaques; the local inflammatory response and plaque stability. Synthetic ligands for PPAR have been developed; however, natural ligands include specific fatty acids and their metabolites. Though the role of PPAR in atherosclerosis has been reported with respect to synthetic ligands, additional studies need to be done with established and possible natural ligands. In this review, we will focus on the relation of dietary fat to PPAR alteration of atherosclerosis.

The Characteristics of Cooling Performance on 7RT Ammonia Absorption System (7RT급 암모니아 흡수식 냉온수기의 냉방성능 특성)

  • Lee, Ho-Saeng;Jin, Byoung-Ju;Yoon, Jung-In;Hwang, Jun-Hyeon;Jin, Slm-Won;Kyung, Ick-Soo;Erickson, Donald C
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.21 no.8
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    • pp.433-438
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    • 2009
  • Experimental results for performance characteristics of small $NH_3$ absorption chiller/ heater are presented. The apparatus consists of 7RT water-cooled absorption system, solution pump, boiler, cooling tower and peripheral devices. The effect of experimental parameters, such as refrigerant mass flow rate, solution mass flow rate and cooling water temperature have been investigated in view of the system performance. The capacity of each heat exchanger increased as refrigerant mass flow rate increased in cooling mode. Also, a cooling capacity increased as a strong solution mass flow rate increased. The cooling and heating COP show 0.5, 1.5 regardless of refrigerant mass flow rate, respectively. The results focus on the evaluation for performance characteristics of system with respect to variation of refrigerant mass flow rate under standard design conditions.

Meeting Recommended Levels of Physical Activity in Relation to Preventive Health Behavior and Health Status Among Adults

  • Hart, Peter D.;Benavidez, Gabriel;Erickson, James
    • Journal of Preventive Medicine and Public Health
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    • v.50 no.1
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    • pp.10-17
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    • 2017
  • Objectives: The purpose of this study was to examine the relationship of meeting the recommended levels of physical activity (PA) with health status and preventive health behavior in adults. Methods: A total of 5630 adults 18 years of age or older were included in this study. PA was assessed using a series of questions that categorized activities based on their metabolic equivalent values and then categorized individuals based on the reported frequency and duration of such activities. Participants reporting 150 minutes or more of moderate-intensity PA per week were considered to have met the PA guidelines. Multiple logistic regression was used to model the relationships between meeting PA guidelines and health status and preventive health behavior, while controlling for confounding variables. Results: Overall, 53.9% (95% confidence interval [CI], 51.9 to 55.9%) of adults reported meeting the recommended levels of PA. Among adults with good general health, 56.9% (95% CI, 54.7 to 59.1%) reported meeting the recommended levels of PA versus 43.1% (95% CI, 40.9 to 45.3%) who did not. Adults who met the PA guidelines were significantly more likely not to report high cholesterol, diabetes, chronic obstructive pulmonary disease, arthritis, asthma, depression, or overweight. Furthermore, adults meeting the PA guidelines were significantly more likely to report having health insurance, consuming fruits daily, consuming vegetables daily, and not being a current cigarette smoker. Conclusions: In this study, we found meeting the current guidelines for PA to have a protective relationship with both health status and health behavior in adults. Health promotion programs should focus on strategies that help individuals meet the current guidelines of at least 150 minutes per week of moderate-intensity PA.