• Journal of Dairy Science and Biotechnology
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• v.33 no.1
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• pp.35-46
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• 2015

Recently, much attention has been paid to the development of a value-added food category containing probiotics so as to improve human health and prevent diseases. Among various foods, the health benefits of milk and dairy products are known to humanity, and could be attributed to the bioactive components present in milk. In fermented milk products, the health benefits could be due to suitable modulation activities produced by the action of probiotic bacteria. Besides the modification of various milk components, probiotics might also act directly as preventive and therapeutic agents against some severe diseases. Probiotics promote health via their positive effects on the immune response, stimulation of natural immunity, and modulation of the production of antimicrobial peptides, cytokines, and so on. Whey proteins, a byproduct of cheese production could also have anticarcinogenic, immunostimulatory, antimicrobial, and health-promoting activities such as improving insulin sensitivity and reducing fat deposition. Therefore, milk and dairy products containing probiotics could provide various opportunities in the field of functional foods. Additionally, these functional foods may be important in the human diet and may help improve human health and prevent diseases.

• Korean Journal of Food Science and Technology
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• v.45 no.2
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• pp.148-155
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• 2013

Sulfoxaflor is a new active ingredient within the sulfoximine insecticide class that acts via a unique interaction with the nicotinic receptor. The MRLs (maximun residue limit) of sulfoxaflor in apple and pear are set at 0.4 mg/kg and that in pepper is set at 0.5 mg/kg. The purpose of this study was to develop an analytical method for the determination of sulfoxaflor residues in agricultural commodities using HPLC-UVD and LC-MS. The analysis of sulfoxaflor was performed by reverse phase-HPLC using an UV detector. Acetone and methanol were used for the extraction and aminopropyl ($NH_2$) cartridge was used for the clean-up in the samples. Recovery experiments were conducted on 7 representative agricultural products to validate the analytical method. The recoveries of the proposed method ranged from 82.8% to 108.2% and relative standard deviations were less than 10%. Finally, LC-MS with selected ion monitoring was also applied to confirm the suspected residues of sulfoxaflor in agricultural commodities.

• Horticultural Science & Technology
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• v.33 no.4
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• pp.585-590
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• 2015

This study was conducted to improve the acclimatization rate of in vitro strawberry plantlets through bioreactor culture using the growth retardant flurprimidol. Different concentrations [0 (Control), 0.1, 0.5, 1.0, and $2.0mg{\cdot}L^{-1}$] of flurprimidol were added during bioreactor culture. After six weeks of treatments, various growth characteristics were investigated and in vitro plantlets were acclimated in the greenhouse. The growth rate of treated plantlets was much lower than that of control, and as the treatment concentration increased, the growth rate was much decreased. Shoots of plantlets treated with flurprimidol were shorter (2.2-3.7 cm) than those of control (7.9 cm). The number of roots per treated plant was around 11.6-34.2, compared with 51.8 in the control. Root length was also lower (0.88-3.08 cm) than control (4.36 cm). However, the number of new shoots and leaves increased in all treatments except for $2.0mg{\cdot}L^{-1}$ concentration. The root was partially decayed in $1.0mg{\cdot}L^{-1}$ concentration and was completely decayed in $2.0mg{\cdot}L^{-1}$. The survival rate in $0.1mg{\cdot}L^{-1}$ and $0.5mg{\cdot}L^{-1}$ concentrations was 100% and 23.3% respectively. After four weeks of acclimatization, the plantlets restarted growth, and growth characteristics of shoots and roots recovered to the levels of control, except for fresh weight. Based on our results, a concentration of $0.1mg{\cdot}L^{-1}$ flurprimidol is appropriate for improvement of acclimatization rate of in vitro strawberry plantlets in bioreactor culture.

• Horticultural Science & Technology
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• v.31 no.2
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• pp.246-254
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• 2013

Five isolates of Tomato yellow leaf curl virus (TYLCV) collected from various regions of Korea were amplified using PCR and determined the sequences of full-length genome, respectively. The PCR-amplified DNA of each TYLCV isolate was introduced into a binary vector to construct infectious clone containing 1.9 copies of the corresponding viral genome. Various cultivars and breeding lines of tomato were inoculated with Agrobacterium tumefaciens harboring infectious clone of each TYLCV isolate to assess resistance against TYLCV. Susceptible cultivar 'Super-sunread' revealed typical yellowing and narrowing of the upper leaves. In contrast, breeding linesTY12, GC9, GC171, and GC173, which contained the TY-1 and/or TY-3 genes that confer resistance against TYLCV in nature, were completely symptomless, suggesting that the lines were resistant to challenging TYLCV isolates. Symptoms of TYLCV in susceptible tomato cultivars are significantly different from those of TYLCV in the resistant tomato cultivars at 30 days after agroinfiltration. Although genomic DNAs of TYLCV were detected from the breeding lines TY12, GC9, GC171, and GC173 using real-time PCR analysis with specific primers, levels of TYLCV DNA accumulation in the resistant breeding lines were much lower than those of TYLCV DNA accumulation in susceptible tomato cultivars. Similar symptom severity and levels of TYLCV DNA accumulation were observed from TYLCV infections mediated by Bemisia tabaci in the resistant and susceptible tomato cultivars. Concentration of agrobacterium did not affect the response of tomato cultivars against TYLCV inoculation. Taken together, these results suggest that TYLCV inoculation via agroinfiltration is as effective as inoculation through Bemisia tabaci and is useful for breeding programs of TYLCV-resistant tomato.

• Journal of Internet Computing and Services
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• v.18 no.1
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• pp.105-119
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• 2017

Smartphone users hit over eighty-five percentage of Korean populations and personal private items and various information are stored in each user's smartphone. There are so many cases to propagate malicious codes or spywares for the purpose of catching illegally these kinds of information and earning pecuniary gains. Thus, need of information security is outstanding for using smartphone but also user's security perception is important. In this paper, we investigate about how information security affects smartphone operating system choices by users. For statistical analysis, the online survey with questionnaires for users of smartphones is conducted and effective 218 subjects are collected. We test hypotheses via communalities analysis using factor analysis, reliability analysis, independent sample t-test, and linear regression analysis by IBM SPSS statistical package. As a result, it is found that hardware environment influences on perceived ease of use. Brand power affects both perceived usefulness and perceived ease of use and degree of personal risk-accepting influences on perception of smartphone spy-ware risk. In addition, it is found that perceived usefulness, perceived ease of use, degree of personal risk-accepting, and spy-ware risk of smartphone influence significantly on intention to purchase smartphone. However, results of independent sample t-test for each operating system users of Android or iOS do not present statistically significant differences among two OS user groups. In addition, each result of OS user group testing for hypotheses is different from the results of total sample testing. These results can give important suggestions to organizations and managers related to smartphone ecology and contribute to the sphere of information systems (IS) study through a new perspective.

• Korean Journal of Environmental Agriculture
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• v.28 no.1
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• pp.20-24
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• 2009

This study was conducted to investigate the roles of co-existed organic materials (OM) with different biodegradability in composting of cattle manure in terms of $CO_2$ emission and $NH_3$ volatilization. Either sawdust (SD, low biodegradability) or rice bran (RB, high biodegradability) was mixed with cattle manure at a various rate and the amounts of $CO_2$ emission and $NH_3$ volatilization were determined periodically during 4 weeks of composting. Percentage of dry matter loss during the composting period was also calculated. The amount of $CO_2$ emitted increased with increasing rate of OM and was significantly (P<0.01) higher in the RB treatment than in the SD treatment by 43 to 122% depending on the rate of OM Accordingly, % of dry matter loss during 4 weeks of composting was higher in the RB (rang: from 35.1 % to 41.5%) than that in the SD treatments (from 18.7% to 22.6%), showing that RB is more biodegradable than SD. During the early composting period up to 8 days, negligible amount of ammonia volatilization was detected in both treatments regardless of application rates. In the RB treatment, substantial amount of ammonia volatilization was detected thereafter, however, no meaningful ammonia volatilization was observed in the SD treatment until the end of composting. Such differences could be attributed to the different properties of SD and RB. For example, the high C/N ratio of SD could enhance $NH_4^+$ immobilization and thus decrease $NH_4^+$ concentration that is susceptible to ammonia volatilization. Binding of $NH_4^+$ on to phenolic compounds of SD may also contribute to the decrease in $NH_4^+$ concentration. Meanwhile, as RB has a relatively low C/N ratio, remineralization of immobilized $NH_4^+$ could increase $NH_4^+$ concentration as high as the level for the occurrence of ammonia volatilization. Therefore, our study suggests that OM which is resistant to biodegradation can reduce $NH_3$ volatilization largely by physico-chemical pathways across the entire composting period and that easily biodegradable OM can retard $NH_3$ volatilzation via microbial immobilization in the early period of composting followed by rapid remineralization, leading to substantial volatilization of $NH_3$ in the middle stage of composting.

• Korean Journal of Environmental Agriculture
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• v.28 no.3
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• pp.249-257
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• 2009

Surface runoff and erosion are responsible for extensive losses of top soil and agricultural productivity. In this study, a laboratory experiment was conducted to investigate the effects of different polyacrylamides (PAM) on the protection of soil from erosion and turbidity in loamy sand soil. To accomplish this, 10 and 40 kg $ha^{-1}$ of PAM were applied to the soil surface. The effects of rainfall on 10 and 20% slopes were then evaluated in the laboratory using a rainfall simulator. After air drying, the surface was subjected to rain at 30 mm $hr^{-1}$. The silt+clay of the runoff from samples treated with 10 kg PAM $ha^{-1}$ reduced by 43% and 13% when the 10% and 20% slopes were evaluated, respectively, when compared with the tap water without PAM treatment as control. The mean contents of silt+clay were reduced as the amount of PAMs applied increased at both slopes. Specifically, samples treated with 40 kg PAM $ha^{-1}$ showed reductions in the silt+clay of the runoff to 88% and 85% when the 10% and 20% slopes were evaluated, respectively, when compared to control. Furthermore, the mean turbidity of runoff in the 40 kg PAM $ha^{-1}$ treatment was reduced to 94.7% and 84.8% when the samples were subjected to 10% and 20% slopes, respectively, when compared to the control. Taken together, these findings indicate that PAM treatment will improve water pollution and agricultural productivity on sloped land via a reduction in soil erosion.

• Applied Microscopy
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• v.37 no.4
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• pp.271-280
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• 2007

Tonicity-responsive enhancer binding protein(TonEBP) is a transcriptional factor essential in the function and development of the renal medulla. TonEBP plays a critical role in protecting renal medullary cells from the deleterious effect of hypertonicity. TonEBP is a key regulator of urinary concentration via stimulation of transcription of urea transporter(UT) in a manner independent of vasopressin. UT in the renal inner medulla is important for the conservation of body water due to its role in the urine concentrating mechanism. Mongolian gerbil(Meriones unguiculatus) has been as an model animal for studying the neurological disease such as stroke and epilepsy because of the congenital incomplete in Willis circle, as well as the investigation of water metabolism because of the long time-survival in the condition of water-deprived desert condition, compared with other species animal. In this study, we divide 3 groups of which each group include the 5 animals. In the study of 7 or 14 days water restricted condition, we investigated the TonEBP and UT-A by using a immunohistochemistry in the kidney. In the normal kidney, the distribution of TonEBP is generally localized on nuclei of inner medullary cells. Nuclear distribution of TonEBP is generally increased throughout the medulla in 7 and 14 days dehydrated group compared with control group. Increased nuclear localization was particularly dramatic in thin limbs. In control groups, UT-A was expressed in inner stripe of outer medulla(ISOM) and inner medulla(IM). UT-A was present in the terminal part of the short-loop of descending thin limbs (DTL) in ISOM and also present in the inner medullary collecting duct(IMCD), where the intensity of it gradually increased toward the papillary tip. In the dehydrated kidney, UT-A immunoreactivity was increased in the short-loop of DTL in ISOM and in the long-loop of DTL in the initial part of IM, where was expressed moderate positive reaction in the normal kidney. Also it was up regulated in the IMCD in initial & middle part of IM. However UT-A down regulated in the IMCD, where the intensity of it gradually decreased toward the papillary tip. These findings suggest that increased levels of TonEBP in medulla and UT-A in shot-loop of DTL and IMCD play a important role for maintain fluid balance in the water-deprived mongolian gerbil kidney.

• Childhood Kidney Diseases
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• v.6 no.2
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• pp.198-208
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• 2002

Purpose : There is no scientific basis for an immunization policy for children with renal disease who have increased risk of infection in Korea. As an initial step in approaching this problem, this survey of pediatric nephrologists was undertaken to determine the current recommendations of practicing pediatric nephrologists Methods : Questionnaires were sent to the members of Korean Society of Pediatric Nephrology via mail and E-mail. The questionnaire was designed to obtain information about the immunization practice of basic vaccination schedule for nephrotic syndrome, the side effects after vaccination and the immunization practice about recommended vaccines for children with renal disease. Results : Questionnaires were sent to 56 pediatric nephrologists. 35 replies were received (response rate: 62.5%). Almost of the respondents (82.8%) reported practicing at university hospital. All respondents reported modified vaccination schedule. 65.7% of the respondents immunized nephrotic children with live vaccines some time later after discontinuation of corticosteroids treatment and 57.1% of respondents immunized them with killed vaccines during medication of low doses of corticosteroids. Respondents experienced relapse of nephrotic syndrome after vaccination are nine, lack of vaccine efficacy are three and infection by organisms of live vaccines are two. 71.4% of respondents reported vaccinating children with renal disease for hepatitis B, pneumococcus and influenza during medication of low doses of corticosteroids. But There is few difference of the rates of respondents vaccinating them for Hemophilus influenzae type b between during medication of low doses of corticosteroids and after discontinuation of corticosteroids treatment (45.7% us 42.9%). Almost of respondents reported vaccinating renal failure children without immunosuppression for hepatitis B, pneumococcus, influenza and H. influenzae type b ($54.3{\sim}77.1%$). Conclusion : Pediatric nephrologists practiced modifying vaccination schedules for children with renal disease in Korea and there was variation according to the progression of disease and the doses of corticosteroids. It is necessary to establish the immunization guideline for children with renal disease through the prospective studies.

• Korean Journal of Poultry Science
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• v.37 no.2
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• pp.139-143
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• 2010

Quail is a very useful animal model for studying vertebrate development because of its small body size and unique reproductive traits. This species is also ideal model for producing germline chimeras via transferring exogenous primordial germ cells (PGCs) into the recipient embryo. To increase the contribution efficiency of donor PGCs into recipients' tissues, decreasing the population of endogenous PGCs has been rate-limiting factor. We therefore conducted this study to investigate if gamma ($\gamma$)-irradiation depletes endogenous PGCs in developing quail embryo. Firstly, freshly laid stage X quail embryos were irradiated with various output of $\gamma$-irradiation and its teratogenic effect on the embryo was evaluated. Although a dose-dependent increase in the number of embryo showing malformation was found as the output increased (0, 250, 500, 750, and 1,000 rads), only a maximum of 10.1% of embryos were abnormal in 1,000 rads. Immunocytochemical analysis using the QCR1 antibody, which is specific marker for quail PGCs, was conducted to analyze the effect of sterilization. As results, $\gamma$-rays at a dose-rate of 500 rads/73 sec onto undeveloped stage X embryo significantly reduced the number of germ cells to an average of 75.55 % and 82.03 % in male and female embryos, respectively. We conclude that $\gamma$-ray selectively targets PGCs while affects minimally to the somatic development in quail embryo. Our results will not only provide important data for germline chimera production but can be used for analyzing the effect of ionized rays on the differentiating germ cells in various stages during animal development.