414 research outputs found
New microbial ecosystem created by artificak floating island
To scrutinize the microbial ecosystem and processing of water quality improvement under the artificial floating island, water quality parameteres, bacterial numbers and extracellular enzyme activities were measured biweekly flom 3, November 2001 to 20,April 2002 in Lake Paldang, Korea. Most of the mean encironmental parameters were not different from artificially floating island (AFI) site and control site. But,zooplankton numbers were about 100 times higher at AFI site than those of control site, even though the chlorophyll α concentrations were not so different. During winter, the rations of respiratory active bacteria to total bacterial number were two fold higher and enzyme activities of β-glucosidase and phosphatase were extremely higher at AFI site than those of contrl site. With these high densities of zooplankton, active bacteria and high rates of degradation under the AFI, the organic materials are eliminated at inside of lake with newly created ecosystem.Article信州大学山地水環境教育研究センター研究報告 2: 5-9(2004)departmental bulletin pape
Characterization of cationic dextrin prepared by ultra high pressure (UHP)-assisted cationization reaction
AbstractCationic dextrins were prepared through substitution reaction of dextrin with low and high addition levels of 2,3-epoxypropyltrimethylammonium chloride (ETMAC), respectively. Conventional cationization reactions were carried out for 5h under continued stirring. UHP-assisted cationization reactions were conducted at three pressurization levels of 100, 300 and 500MPa for a pressure holding time of 30min. Degree of substitution (DS) of UHP-assisted cationic dextrins ranged from 0.58 to 1.51, and in general, their DS values were enhanced with increasing pressure levels. FT-IR and 13C NMR spectra indicated the presence of CN bond, which provided clear evidence about incorporation of cationic moieties onto dextrin molecules. In flocculation test, UHP-assisted cationic dextrin revealed higher flocculating activity. Overall results suggested that UHP-assisted cationization reaction could modulate reactivity and flocculating activity of dextrin by controlling pressure levels and reaction mixture compositions, and cationic dextrins likely possessed a higher potential to replace synthetic polymer-based flocculants
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Anti-photoaging effect of fermented agricultural by-products on ultraviolet B-irradiated hairless mouse skin
Processed products from agricultural produce generate a large number of agricultural by‑products that contain a number of functional substances. These are often discarded owing to the lack of suitable processing methods. The present study investigated the anti‑photoaging properties of fermented rice bran (FRB), soybean cake (FSB) and sesame seed cake (FSC) on ultraviolet B (UVB)‑irradiated hairless mouse skin. Results indicated that the oral administration of FRB, FSB and FSC effectively inhibited the UVB irradiation‑induced expression of matrix metalloproteinase (MMP)‑2, MMP‑9, MMP‑3 and MMP‑13. Reverse transcription‑quantitative polymerase chain reaction results also demonstrated that FRB, FSB and FSC significantly inhibited the UVB‑induced expression of the genes encoding tumor necrosis factor‑α, inducible nitric oxide synthase, interleukin (IL)‑6 and IL‑1β when compared with the UVB‑vehicle group (P\u3c0.05). Additionally, collagen degradation and mast cell infiltration were reduced in hairless mouse skin. Furthermore, UVB‑induced wrinkle formation was also significantly reduced in mouse skin compared with the UVB‑vehicle group (P\u3c0.05). These results reveal that fermented agricultural by‑products may serve as potential functional materials with anti‑photoaging activities
Relationship Between Earlobe Crease and Brachial-ankle Pulse Wave Velocity in Non-hypertensive, Non-diabetic Adults in Korea
OBJECTIVES: Several studies have found a significant association between the presence of earlobe crease (ELC) and cardiovascular disease (CVD). Brachial-ankle Pulse Wave Velocity (baPWV) is a non-invasive and useful measure of arterial stiffness predicting cardiovascular events and mortality. However, few studies have reported the relationship between ELC and baPWV as a new measure of arterial stiffness. the purpose of this study was to determine whether ELC is related to baPWV in non-diabetic, non-hypertensive, and apparently healthy Korean adults.
METHODS: A cross-sectional study was conducted on 573 non-hypertensive, non-diabetic Korean adults aged 20-80 yr. Subjects were stratified into three groups according to gender and menopausal status. baPWV was measured by an automatic waveform analyser. the association between ELC and baPWV was assessed by multiple linear regression analysis after adjusting for conventional cardiovascular disease risk factors including age, gender, blood pressure, lipid profile, and smoking status etc.
RESULTS: the overall frequency of ELC was 19.02% and the subjects with ELC showed significantly higher mean baPWV (p<0.0001). Multiple linear regression of subjects revealed that the presence of ELC was independently associated with baPWV (male, p<0.0001; premenopausal female p=0.0162; postmenopausal female p=0.0208).
CONCLUSION: ELC had a significant correlation with baPWV, independently controlling for other classical cardiovascular risk factors in adults aged 20 yr or older. ELC is an important surrogate marker of increased arterial stiffness as measured by baPWV in Korean adults.ope
Wireless thin film transistor based on micro magnetic induction coupling antenna
A wireless thin film transistor (TFT) structure in which a source/drain or a gate is connected directly to a micro antenna to receive or transmit signals or power can be an important building block, acting as an electrical switch, a rectifier or an amplifier, for various electronics as well as microelectronics, since it allows simple connection with other devices, unlike conventional wire connections. An amorphous indium gallium zinc oxide (α-IGZO) TFT with magnetic antenna structure was fabricated and studied for this purpose. To enhance the induction coupling efficiency while maintaining the same small antenna size, a magnetic core structure consisting of Ni and nanowires was formed under the antenna. With the micro-antenna connected to a source/drain or a gate of the TFT, working electrical signals were well controlled. The results demonstrated the device as an alternative solution to existing wire connections which cause a number of problems in various fields such as flexible/wearable devices, body implanted devices, micro/nano robots, and sensors for the 'internet of things' (IoT).1
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