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1.
Nutr Metab Cardiovasc Dis ; 29(5): 489-495, 2019 05.
Article in English | MEDLINE | ID: mdl-30940491

ABSTRACT

BACKGROUND AND AIMS: It is not known whether non alcoholic fatty liver disease (NAFLD) is a risk factor for diabetes in non obese, non centrally-obese subjects. Our aim was to investigate relationships between fatty liver, insulin resistance and a biomarker score for liver fibrosis with incident diabetes at follow up, in subjects who were neither obese nor centrally-obese. METHODS AND RESULTS: As many as 70,303 subjects with a body mass index (BMI) < 25 kg/m2 and without diabetes were followed up for a maximum of 7.9 years. At baseline, fatty liver was identified by liver ultrasound, insulin resistance (IR) by homeostatic model assessment of insulin resistance (HOMA-IR) ≥2.0, and central obesity by waist circumference (waist circumference ≥90 cm (men) and ≥85 cm (women). The Fibrosis-4 (FIB-4 score) was used to estimate extent of liver fibrosis. Cox proportional hazards models adjusted for confounders were used to estimate hazard ratios (aHRs) for incident diabetes. As many as 852 incident cases of diabetes occurred during follow up (median [IQR] 3.71 [2.03] years). Mean ± SD BMI was 22.8 ± 1.8 and 21.7 ± 2.0 kg/m2 in subjects with and without diabetes at follow up. In subjects without central obesity and with fatty liver, aHRs (95% CI) for incident diabetes at follow up were 2.17 (1.56, 3.03) for men, and 2.86 (1.50,5.46) for women. Similar aHRs for incident diabetes occurred with fatty liver, IR and the highest quartile of FIB-4 combined, in men; and there was a non significant trend toward increased risk in women. CONCLUSIONS: In normal weight, non-centrally obese subjects NAFLD is an independent risk factor for incident diabetes.


Subject(s)
Diabetes Mellitus/epidemiology , Non-alcoholic Fatty Liver Disease/epidemiology , Adult , Body Mass Index , Diabetes Mellitus/diagnosis , Female , Humans , Ideal Body Weight , Incidence , Insulin Resistance , Liver Cirrhosis/epidemiology , Male , Middle Aged , Non-alcoholic Fatty Liver Disease/diagnostic imaging , Republic of Korea/epidemiology , Risk Assessment , Risk Factors , Sex Factors , Time Factors
2.
Environ Geochem Health ; 41(4): 1793-1803, 2019 Aug.
Article in English | MEDLINE | ID: mdl-28845510

ABSTRACT

This study was conducted to establish the optimal application conditions of barley straw biochar (BC) for rice cultivation and to determine the effects of combined application of BC and inorganic fertilizer (IF) on rice cultivation in a paddy field. Based on the characteristics of rice growth in pot-based experiments, the selected optimal application conditions of BC were application of 20 ton ha-1 at 14 days before rice transplanting. The effects of BC application on rice cultivation in a paddy field when using those conditions were then evaluated. Each treatment was separated by a control (Cn), IF, BC, and combined BC + IF treatments, respectively. The rice yields in the BC + IF treatment were 38.6, 21.7, and 24.5% greater than those in the Cn, IF, and BC treatments, respectively. In addition, yield components of rice were significantly improved in the BC + IF treatment relative to the other treatments. Following rice harvest, soil status was improved, showing greater soil aggregation stability, decreased bulk density, and increased porosity in the BC-treated areas compared to those in the Cn- and IF-treated areas. At the time of rice harvesting, soil chemical properties such as pH, EC, SOC, TN, Avail. P2O5, and CEC in the BC-treated areas were improved over those in other areas. The results of this study indicate that using BC as a soil amendment is effective at improving rice cultivation and can benefit the soil environment.


Subject(s)
Agriculture/methods , Charcoal , Fertilizers , Hordeum/chemistry , Oryza/growth & development , Carbon/analysis , Hydrogen-Ion Concentration , Nitrogen/analysis , Plant Stems/chemistry , Republic of Korea , Soil/chemistry
3.
Environ Geochem Health ; 37(6): 969-83, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26040973

ABSTRACT

The phosphorus (P) adsorption characteristic of sesame straw biochar prepared with different activation agents and pyrolysis temperatures was evaluated. Between 0.109 and 0.300 mg L(-1) in the form of inorganic phosphate was released from raw sesame straw biochar in the first 1 h. The release of phosphate was significantly enhanced from 62.6 to 168.2 mg g(-1) as the pyrolysis temperature increased. Therefore, sesame straw biochar cannot be used as an adsorbent for P removal without change in the physicochemical characteristics. To increase the P adsorption of biochar in aqueous solution, various activation agents and pyrolysis temperatures were applied. The amount of P adsorbed from aqueous solution by biochar activated using different activation agents appeared in the order ZnCl2 (9.675 mg g(-1)) > MgO (8.669 mg g(-1)) ⋙ 0.1N-HCl > 0.1N-H2SO4 > K2SO4 ≥ KOH ≥ 0.1N-H3PO4, showing ZnCl2 to be the optimum activation agent. Higher P was adsorbed by the biochar activated using ZnCl2 under different pyrolysis temperatures in the order 600 °C > 500 °C > 400 °C > 300 °C. Finally, the amount of adsorbed P by activated biochar at different ratios of biochar to ZnCl2 appeared in the order 1:3 ≒ 1:1 > 3:1. As a result, the optimum ratio of biochar to ZnCl2 and pyrolysis temperature were found to be 1:1 and 600 °C for P adsorption, respectively. The maximum P adsorption capacity by activated biochar using ZnCl2 (15,460 mg kg(-1)) was higher than that of typical biochar, as determined by the Langmuir adsorption isotherm. Therefore, the ZnCl2 activation of sesame straw biochar was suitable for the preparation of activated biochar for P adsorption.


Subject(s)
Charcoal/chemistry , Phosphorus/chemistry , Water Pollutants, Chemical/chemistry , Adsorption , Biomass , Chlorides/chemistry , Environmental Restoration and Remediation , Hot Temperature , Sesamum , Zinc Compounds/chemistry
4.
Rev Sci Instrum ; 81(10): 10E107, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21033972

ABSTRACT

Within the scope of long term research on imaging diagnostics for steady-state plasmas and understanding of edge plasma physics through diagnostics with conventional spectroscopic methods, we have constructed a linear electron cyclotron resonance (ECR) plasma device named Research on Advanced Plasma Imaging and Dynamics (RAPID). It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. Here, a 6 kW 2.45 GHz magnetron is used to produce steady-state hydrogen, helium, and argon plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). In order to achieve the highest possible plasma performance within the limited input parameters, wall conditioning experiments were carried out. Chamber bake-out was achieved with heating coils that were wound covering the vessel, and long-pulse electron cyclotron heating discharge cleaning was also followed after 4 days of bake-out. A uniform bake-out temperature (150 °C) was achieved by wrapping the vessel in high temperature thermal insulation textile and by controlling the heating coil current using a digital control system. The partial pressure changes were observed using a residual gas analyzer, and a total system pressure of 5×10(-8) Torr was finally reached. Diagnostic systems including a millimeter-wave interferometer, a high resolution survey spectrometer, a Langmuir probe, and an ultrasoft x-ray detector were used to provide the evidence that the plasma performance was improved as we desired. In this work, we present characterization of the RAPID device for various system conditions and configurations.

5.
Rev Sci Instrum ; 81(10): 10E116, 2010 Oct.
Article in English | MEDLINE | ID: mdl-21033981

ABSTRACT

The technique used until recently utilizing the Ne-He laser for imaging bolometer foils calibration [B. J. Peterson et al., J. Plasma Fusion Res. 2, S1018 (2007)] has showed several issues. The method was based on irradiation of 1 cm spaced set of points on a foil by the laser beam moved by set of mirrors. Issues were the nonuniformity of laser power due to the vacuum window transmission nonuniformity and high reflection coefficient for the laser. Also, due to the limited infrared (IR) window size, it was very time consuming. The new methodology uses a compact ultraviolet (uv) light-emitting diodes installed inside the vacuum chamber in a fixed position and the foil itself will be moved in the XY directions by two vacuum feedthroughs. These will help to avoid the above mentioned issues due to lack of a vacuum window, fixed emitters, higher uv power absorption, and a fixed IR camera position.

6.
Rev Sci Instrum ; 81(6): 063502, 2010 Jun.
Article in English | MEDLINE | ID: mdl-20590236

ABSTRACT

The first plasma with target values of the plasma current and the pulse duration was finally achieved on June 13, 2008 in the Korea Superconducting Tokamak Advanced Research (KSTAR). The diagnostic systems played an important role in achieving successful first plasma operation for the KSTAR tokamak. The employed plasma diagnostic systems for the KSTAR first plasma including the magnetic diagnostics, millimeter-wave interferometer, inspection illuminator, H(alpha), visible spectrometer, filterscope, and electron cyclotron emission (ECE) radiometer have provided the main plasma parameters, which are essential for the plasma generation, control, and physics understanding. Improvements to the first diagnostic systems and additional diagnostics including an x-ray imaging crystal spectrometer, reflectometer, ECE radiometer, resistive bolometer, and soft x-ray array are scheduled to be added for the next KSTAR experimental campaign in 2009.

7.
Rev Sci Instrum ; 80(10): 103503, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19895060

ABSTRACT

The research on advanced plasma imaging and dynamics (RAPID) device is a newly developed linear electron cyclotron resonance (ECR) plasma device. It has a variety of axial magnetic field profiles provided by eight water-cooled magnetic coils and two dc power supplies. The positions of the magnetic coils are freely adjustable along the axial direction and the power supplies can be operated with many combinations of electrical wiring to the coils. A 6 kW 2.45 GHz magnetron is used to produce steady-state ECR plasmas with central magnetic fields of 875 and/or 437.5 G (second harmonic). The cylindrical stainless steel vacuum chamber is 300 mm in diameter and 750 mm in length and has eight radial and ten axial ports including 6-in. and 8-in. viewing windows for heating and diagnostics. Experimental observation of ECR plasma heating has been recently carried out during the initial plasma operation. The main diagnostic systems including a 94 GHz heterodyne interferometer, a high-resolution 25 channel one-dimensional array spectrometer, a single channel survey spectrometer, and an electric probe have been also prepared. The RAPID device is a flexible simulator for the understanding of tokamak edge plasma physics and new diagnostic system development. In this work, we describe the RAPID device and initial operation results.

8.
Rev Sci Instrum ; 79(8): 083504, 2008 Aug.
Article in English | MEDLINE | ID: mdl-19044346

ABSTRACT

To monitor the global formation of the initial plasma and damage to the internal structures of the vacuum vessel, an in-vessel visible inspection system has been installed and operated on the Korean superconducting tokamak advanced research (KSTAR) device. It consists of four inspection illuminators and two visible/H-alpha TV cameras. Each illuminator uses four 150 W metal-halide lamps with separate lamp controllers, and programmable progressive scan charge-coupled device cameras with 1004 x 1004 resolution at 48 framess and a resolution of 640 x 480 at 210 framess are used to capture images. In order to provide vessel inspection capability under any operation condition, the lamps and cameras are fully controlled from the main control room and protected by shutters from deposits during plasma operation. In this paper, we describe the design and operation results of the visible inspection system with the images of the KSTAR Ohmic discharges during the first plasma campaign.

9.
Water Sci Technol ; 55(1-2): 105-11, 2007.
Article in English | MEDLINE | ID: mdl-17305129

ABSTRACT

A heavy metal resistant bacterium Bacillus spp. strain CPB4 was isolated from heavy metal contaminated soil in Korea and further characterised. The CPB4 strain showed a high capacity for uptake of heavy metal Pb (Pb > Cd > Cu > Ni > Co > Mn > Cr > Zn) both in single and in mixed heavy metal solution. Optimal conditions for heavy metal uptakes of CPB4 strain were 20-40 degrees C culture temperature, 5-7 pH and 24 h pre-culture times. TEM showed that large amounts of the electron-dense granules (heavy metal complexes) were found mainly on the cell wall and cell membrane. Furthermore, more than 90% of adsorbed heavy metals were distributed both in cell wall and in cell membrane fractions. The amount of heavy metal uptake was remarkably decreased by reducing the crude protein contents when cells were treated by alkali solutions. Therefore, this study showed one of the possible examples for useful bioremediation.


Subject(s)
Bacillus/metabolism , Metals, Heavy/metabolism , Soil Microbiology , Soil Pollutants/metabolism , Adsorption , Bacillus/classification , Biodegradation, Environmental , Cadmium/analysis , Cadmium/metabolism , Chromium/analysis , Chromium/metabolism , Copper/analysis , Copper/metabolism , Hydrogen-Ion Concentration , Korea , Lead/analysis , Lead/metabolism , Metals, Heavy/analysis , Metals, Heavy/chemistry , Microscopy, Electron, Transmission , Nickel/analysis , Nickel/metabolism , Soil Pollutants/analysis , Temperature , Zinc/analysis , Zinc/metabolism
10.
Water Sci Technol ; 55(1-2): 251-9, 2007.
Article in English | MEDLINE | ID: mdl-17305147

ABSTRACT

To treat cutting oil wastewater produced in metal surface treatment industry, Ultrasonication (US)-Fenton process, which is one of the advanced oxidation processes, was used. The optimum conditions to treat non-biodegradable pollutants using the US-Fenton process were that the application rates of H2O2 and FeSO4 were 10% and 3 g/L, respectively, the value of pH was 3, and the ultrasonication time was 30 min. It identified non-degradable pollutants such as ethylene diamine tetraacetic acid (EDTA) and Triethanolamine (TEA) in the cutting oil wastewater. TLC analysis of two compounds of treated water by the coagulation process was similar to that of raw water. However, TLC analysis of two compounds of US-Fenton process was different from that of raw water, meaning that US-Fenton process decomposed the EDTA and TEA. To study the possibility of application with the US-Fenton process to pilot plant, the pollutants treatment efficiency of three different methods, such as US-Fenton process, activated sludge process and coagulation process, in continuous experiments were compared. The removal rate of pollutants by the US-Fenton process according to the effluent time was higher than any other processes. The removal rates of COD, SS, T-N and T-P by US-Fenton process were 98, 93, 75 and 95%, respectively.


Subject(s)
Hydrogen Peroxide/chemistry , Industrial Waste , Iron/chemistry , Ultrasonics , Waste Disposal, Fluid , Water Pollutants, Chemical/chemistry , Water Purification/methods , Biodegradation, Environmental , Environmental Restoration and Remediation , Ferrous Compounds/chemistry , Ferrous Compounds/metabolism , Hydrogen Peroxide/metabolism , Hydrogen-Ion Concentration , Iron/metabolism , Metals/chemistry , Oils , Oxidation-Reduction , Time Factors , Water Pollutants, Chemical/metabolism
11.
Toxicol Appl Pharmacol ; 142(2): 378-85, 1997 Feb.
Article in English | MEDLINE | ID: mdl-9070361

ABSTRACT

Previous studies suggest that menadione is cytotoxic to rat platelets by oxidative stress. In order to elucidate the mechanism of this toxicity, metabolism of menadione and the cytotoxicity of a metabolite, menadione-glutathione conjugate (MEN-SG), were investigated in platelet rich plasma and washed platelet (WP) systems. When menadione was incubated in platelets, the primary metabolite was MEN-SG, which was excreted into the incubation medium. Incubation of subcellular fractions of platelets with synthetic MEN-SG led to increases in oxygen consumption that were similar to the parent compound, menadione. However, unlike menadione, exposure of MEN-SG to intact platelets in WP system neither resulted in increased oxygen consumption nor induced cell lysis as measured by lactate dehydrogenase leakage. In contrast to menadione, levels of MEN-SG in the incubation medium were unaffected by the presence of platelets, suggesting that MEN-SG was not consumed (or taken up) by platelets. These results indicate that even though MEN-SG was able to induce oxidative stress within platelets as potently as menadione itself, the MEN-SG formation from menadione in platelets appeared not to contribute to menadione's cytotoxicity. This lack of MEN-SG toxicity was likely due to its rapid excretion outside the cells.


Subject(s)
Blood Platelets/drug effects , Hemostatics/toxicity , Vitamin K/toxicity , Animals , Blood Platelets/metabolism , Female , Glutathione/metabolism , Hemostatics/metabolism , L-Lactate Dehydrogenase/drug effects , L-Lactate Dehydrogenase/metabolism , Oxygen/metabolism , Plasma/metabolism , Rats , Rats, Sprague-Dawley , Subcellular Fractions/drug effects , Subcellular Fractions/metabolism , Vitamin K/metabolism
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