Mass balance analysis in Korean paddy rice culture     

Chun?G.?YoonEmail author  Jong-Hwa?Ham  Ji-Hong?Jeon 《Paddy and Water Environment》2003,1(2):99-106

A field experimental study was performed during the growing season of 2001 to evaluate water and nutrient balances in paddy rice culture. Three plots of standard fertilization (SF), excessive fertilization (EF, 150% of SF), and reduced fertilization (RF, 70% of SF) were used and the size of treatment plot was 3,000 m², respectively. The hydrologic and water quality was field monitored throughout the crop stages. The water balance analyses indicated that approximately half (47–54%) of the total outflow was lost through surface drainage, with the remainder consumed by evapotranspiration. Statistical analysis showed that there was no significant effect of fertilization rates on nutrient outflow through the surface drainage or rice yield. Reducing fertilization of rice paddy may not work well to mitigate the non-point source nutrient loading in the range of normal farming practices. Instead, the reduction in surface drainage could be important to controlling the loading. Suggestive measures that may be applicable to reduce surface drainage and nutrient losses include water-saving irrigation by reducing ponded water depth, raising the weir height in diked rice fields, and minimizing forced surface drainage as recommended by other researchers. The suggested practices can cause some deviations from conventional farming practices, and further investigations are recommended.  相似文献   

The mechanical properties and abrasion behavior of warp knitted fabrics for footwear     

Youn?Hee?Jeon  Won?Young?Jeong  Jung?Woo?Park  Seung?Kook?AnEmail author 《Fibers and Polymers》2003,4(4):151-155

The abrasion behavior of three kinds of warp knitted fabrics, which are normally used for upper sole of footwear, was evaluated. We measured the changes of mechanical and structural properties of each sample as abrasion cycle increased. Each sample showed similar trends in compression and surface properties but there were significant differences in abrasion rate among the samples. The mechanical properties showed remarkable differences with directions. The frictional coefficient (MIU) of fabric surface increased at the beginning of abrasion and decreased as abrasion cycles increased. The weight and thickness of the fabric linearly decreased with abrasion cycles. The surface roughness (SMD) and the compressional resilience (RC) decreased as abrasion cycles increased while compressional energy (WC) increased.  相似文献   

Antimicrobial resistance, virulence-associated genes, and pulsed-field gel electrophoresis profiles of Salmonella enterica subsp. enterica serovar Typhimurium isolated from piglets with diarrhea in Korea     

Hur J  Choi YY  Park JH  Jeon BW  Lee HS  Kim AR  Lee JH 《Canadian journal of veterinary research》2011,75(1):49-56

Salmonella enterica subsp. enterica serovar Typhimurium was isolated from diarrheic piglets in 2 periods, 2000-2001 (n = 25) and 2005-2006 (n = 17). To compare the characteristics of the isolates collected during the 2 periods, all isolates were tested for antimicrobial resistance, the presence of virulence genes, and pulsed-field gel electrophoresis (PFGE) patterns. All 42 isolates were resistant to at least 1 of the 20 antimicrobials tested, and 39 (93%) were resistant to 2 or more antimicrobials. One isolate was resistant to 12 antimicrobials. Profiles of antimicrobial resistance revealed 20 resistance types. Several isolates were also resistant to quinolones and expanded-spectrum cephalosporins. Ten isolates (24%) were resistant to ampicillin, chloramphenicol, streptomycin, sulfonamides, and tetracycline (ACSSuT); only one isolate had been isolated in 2000-2001, indicating that this type of resistance has rapidly disseminated. Polymerase chain reaction (PCR) assays revealed that all the isolates carried invA. Among the 25 strains isolated in 2000-2001, all carried the sipA, sopA, sopD, sopE2, and ssaR genes, and 96% carried sopB and sifA. Among the 17 strains isolated in 2005-2006, all carried sifA, and approximately 90% carried sipA, sopA, sopB, sopD, sopE2, and ssaR. However, only 6 (14%) of the 42 isolates carried spvC. By PFGE analysis, all 42 strains were classified into 4 major clusters, basically by collection period. The genetic similarity according to PFGE suggests that the strains isolated from diarrheic piglets of this region within the same period may be closely related.  相似文献   

Influence of epidermal growth factor supplementation during in vitro maturation on nuclear status and gene expression of canine oocytes     

Song HJ  Kang EJ  Maeng GH  Ock SA  Lee SL  Yoo JG  Jeon BG  Rho GJ 《Research in veterinary science》2011,91(3):439-445

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In Vitro and In Vivo Anti-Inflammatory Effects of Sulfated Polysaccharides Isolated from the Edible Brown Seaweed,Sargassum fulvellum     

Lei Wang  Hye-Won Yang  Ginnae Ahn  Xiaoting Fu  Jiachao Xu  Xin Gao  You-Jin Jeon 《Marine drugs》2021,19(5)

In the present study, the in vitro and in vivo anti-inflammatory effects of the sulfated polysaccharides isolated from Sargassum fulvellum (SFPS) were evaluated in lipopolysaccharide (LPS)-stimulated RAW 264.7 macrophages and zebrafish. The results indicated that SFPS improved the viability of LPS-stimulated RAW 264.7 macrophages from 80.02 to 86.80, 90.09, and 94.62% at the concentration of 25, 50, and 100 µg/mL, respectively. Also, SFPS remarkably and concentration-dependently decreased the production levels of inflammatory molecules including nitric oxide (NO), tumor necrosis factor-alpha, prostaglandin E₂, interleukin-1 beta, and interleukin-6 in LPS-treated RAW 264.7 macrophages. In addition, SFPS significantly inhibited the expression levels of cyclooxygenase-2 and inducible nitric oxide synthase in LPS-treated RAW 264.7 macrophages. Furthermore, the in vivo test results indicated that SFPS improved the survival rate of LPS-treated zebrafish from 53.33 to 56.67, 60.00, and 70.00% at the concentration of 25, 50, and 100 µg/mL, respectively. In addition, SFPS effectively reduced cell death, reactive oxygen species, and NO levels in LPS-stimulated zebrafish. Taken together, these results suggested that SFPS possesses strong in vitro and in vivo anti-inflammatory activities, and could be used as an ingredient to develop anti-inflammatory agents in the functional food and pharmaceutical industries.  相似文献   

New Cyclic Cystine Bridged Peptides from the Sponge Suberites waedoensis     

Jinhaeng Song  Ju-eun Jeon  Tae Hyung Won  Chung J. Sim  Dong-Chan Oh  Ki-Bong Oh  Jongheon Shin 《Marine drugs》2014,12(5):2760-2770

Two new peptides, chujamides A (1) and B (2), were isolated from the marine sponge Suberites waedoensis, which was collected from Korean waters. Based upon the results of the combined spectroscopic analyses, the structures of these compounds were determined to be proline-riched and cyclic cystine bridged dodeca- and undecapeptides. The absolute configurations of all amino acid residues were determined to be l by advanced Marfey’s analysis. The new compounds exhibited weak cytotoxicities against A549 and K562 cell-lines, and compound 2 also demonstrated moderate inhibitory activity against Na⁺/K⁺-ATPase.  相似文献   

Seaweeds and Their Natural Products for Preventing Cardiovascular Associated Dysfunction     

Bomi Ryu  Young-Sang Kim  You-Jin Jeon 《Marine drugs》2021,19(9)

Cardiovascular disease (CVD), which involves the onset and exacerbation of various conditions including dyslipidemia, activation of the renin–angiotensin system, vascular endothelial cell damage, and oxidative stress, is a leading cause of high mortality rates and accounts for one-third of deaths worldwide. Accordingly, as dietary changes in daily life are thought to greatly reduce the prevalence of CVD, numerous studies have been conducted to examine the potential use of foods and their bioactive components for preventing and treating CVD. In particular, seaweeds contain unique bioactive metabolites that are not found in terrestrial plants because of the harsh environment in which they survive, leading to in vitro and in vivo studies of their prevention and treatment effects. This review summarizes studies that focused on the beneficial effects of seaweeds and their natural products targeting markers involved in a cascade of mechanisms related to CVD pathogenesis. The purpose of this review is to describe the potential of seaweeds and their natural products for preventing and treating CVD based on in vivo and in vitro studies. This review provides a basis for future research in the field of marine drugs.  相似文献   

Saccharobisindole,Neoasterric Methyl Ester,and 7-Chloro-4(1H)-quinolone: Three New Compounds Isolated from the Marine Bacterium Saccharomonospora sp.     

Sohee Kim  Tu Cam Le  Sang-Ah Han  Prima F. Hillman  Ahreum Hong  Sunghoon Hwang  Young Eun Du  Hiyoung Kim  Dong-Chan Oh  Sun-Shin Cha  Jihye Lee  Sang-Jip Nam  William Fenical 《Marine drugs》2022,20(1)

Analysis of the chemical components from the culture broth of the marine bacterium Saccharomonospora sp. CNQ-490 has yielded three novel compounds: saccharobisindole (1), neoasterric methyl ester (2), and 7-chloro-4(1H)-quinolone (3), in addition to acremonidine E (4), pinselin (5), penicitrinon A (6), and penicitrinon E (7). The chemical structures of the three novel compounds were elucidated by the interpretation of 1D, 2D nuclear magnetic resonance (NMR), and high-resolution mass spectrometry (HRMS) data. Compound 2 generated weak inhibition activity against Bacillus subtilis KCTC2441 and Staphylococcus aureus KCTC1927 at concentrations of 32 μg/mL and 64 μg/mL, respectively, whereas compounds 1 and 3 did not have any observable effects. In addition, compound 2 displayed weak anti-quorum sensing (QS) effects against S. aureus KCTC1927 and Micrococcus luteus SCO560.  相似文献   

Historical deposition of trace metals in a marine sapropel from Mangrove Lake,Bermuda with emphasis on mercury,lead, and their isotopic composition     

Jeon  Byunggwon  Scircle  Austin  Cizdziel  James V.  Chen  Jingjing  Black  Oscar  Wallace  Davin J.  Zhou  Ying  Lepak  Ryan F.  Hurley  James P. 《Journal of Soils and Sediments》2020,20(4):2266-2276

Journal of Soils and Sediments - Sapropel is an organic-rich sediment formed under conditions that can result in sequestration of trace metals. Here, we determined the concentration of total...  相似文献   

Inhibition of the type III secretion system of Pseudomonas syringae pv. tomato DC3000 by resveratrol oligomers identified in Vitis vinifera L     

Ji Eun Kang  Byeong Jun Jeon  Min Young Park  Hye Ji Yang  Jaeyoung Kwon  Dong Ho Lee  Beom Seok Kim 《Pest management science》2020,76(7):2294-2303

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