• Asian-Australasian Journal of Animal Sciences
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• 제20권2호
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• pp.200-207
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• 2007

In vitro rumen incubation studies were conducted to determine effects of initial pH on bacterial attachment and fiber digestion. Ruminal fluid pH was adjusted to 5.7, 6.2 and 6.7, and three major fibrolytic bacteria attached to rice straw in the mixed culture were quantified with real-time PCR. The numbers of attached and unattached Fibrobacter succinogenes, Ruminococcus flavefaciens and Ruminocococcus albus were lower (p<0.05) at initial pH of 5.7 without significant difference between those at higher initial pH. Lowering incubation media pH to 5.7 also increased bacterial numbers detached from substrate regardless of bacterial species. Dry matter digestibility, gas accumulation and total VFA production were pH-dependent. Unlike bacterial attachment, maintaining an initial pH of 6.7 increased digestion over initial pH of 6.2. After 48 h in vitro rumen fermentation, average increases in DM digestion, gas accumulation, and total VFA production at initial pH of 6.2 and 6.7 were 2.8 and 4.4, 2.0 and 3.0, and 1.2 and 1.6 times those at initial pH of 5.7, respectively. The lag time to reach above 2% DM digestibility at low initial pH was taken more times (8 h) than at high and middle initial pH (4 h). Current data clearly indicate that ruminal pH is one of the important determinants of fiber digestion, which is modulated via the effect on bacterial attachment to fiber substrates.

• Asian-Australasian Journal of Animal Sciences
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• 제28권11호
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• pp.1662-1668
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• 2015

We investigated differences between effects of natural- and bucket-suckling methods on basal serum oxytocin (OT) and cortisol concentrations, and the effect of OT concentration on affiliative and investigative behavior of calves to a novel object. Ten Japanese Black calves, balanced with birth order, were allocated evenly to natural-suckling (NS) and bucket suckling (BS) groups. Blood samples were collected at the ages of 1 and 2 months (1 week after weaning) calves, and serum OT and cortisol concentrations were measured using enzyme-linked immunosorbent assay and enzymeimmunoassay tests, respectively. Each calf at the age of 2 months (2 weeks after weaning) was released into an open-field with a calf decoy, and its investigative and affiliative behaviors were recorded for 20 minutes. In 1-month-old calves, the basal serum OT concentration ($25.5{\pm}4.9$ [mean${\pm}$standard deviation, pg/mL]) of NS was significantly higher than that of BS ($16.9{\pm}6.7$) (p<0.05), whereas the basal cortisol concentration ($5.8{\pm}2.5$ [mean${\pm}$standard deviation, ng/mL]) of NS was significantly lower than that in BS ($10.0{\pm}2.8$) (p<0.05). Additionally, a negative correlation was noted between serum OT and cortisol concentrations in 1-month-old calves (p = 0.06). Further, the higher serum OT concentration the calves had at 1 month old, the more investigative the calves were at 2 months old but not affiliative in the open-field with a calf decoy. Thus, we concluded that the natural suckling method from a dam elevates the basal serum OT concentration in calves, and high serum OT concentrations induce investigative behavior and attenuate cortisol concentrations.

• Journal of Microbiology and Biotechnology
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• 제12권6호
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• pp.916-920
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• 2002

This report describes a high-level expression of human alpha-2a interferon ($IFN{\alpha}-2a$) in Escherichia coli and its pilot scale purification by using a monoclonal antibody-independent chromatographic procedure that is based on anion-exchange, cation-exchange, hydrophobic interaction, and gel filtration. The recombinant E. coli produced much more $IFN{\alpha}-2a$ in a soluble form, when cultivated at low temperatures than at high-temperature fermentation. However, if the bacterial growth was taken into consideration, fermentation at $30^{\circ}C$ seemed optimal for the interferon production. By using our new protocol, we recovered approximately 160 mg of $IFN{\alpha}-2a$ with a specific activity of $3.59{\times}10^8$ IU/mg from 201 of the broth. The gel permeation chromatographic and SDS-PAGE indicated that the interferon preparation was purified to homogeneity and was of the correctly folded fast-migrating monomer.

• Journal of Biosystems Engineering
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• 제39권4호
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• pp.400-404
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• 2014

Purpose: Concerns over the quantity of available freshwater for agriculture have triggered the development of technologies intended to increase efficiency of water use, especially with regard to irrigation. A new technique called fertirrigation has been developed to use the same irrigation equipment for fertilization. Methods: Since the above-mentioned technique requires care during installation and use on farms, current analysis focuses on some of its characteristics. Results: High uniformity irrigation systems provide the best distribution of fertilizers, especially when used in combination with drip irrigation or micro-aspersion. The factors purity, compatibility, acidification, salinity, and solubility should be taken into account. Conclusions: Fertirrigation provides a significant increase in productivity as it allows for highly controlled nutrient application during the entire growing season. However, it may cause serious problems if misused or overused.

• International Journal of Industrial Entomology and Biomaterials
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• 제37권2호
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• pp.49-54
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• 2018

To artificially enhance antimicrobial peptide expression in Bombyx mori, we constructed genetically engineered silkworms overexpressing Rel family transcription factor. The truncated BmRelish1 (BmRelish1t) gene contained a Rel homolog domain (RHD), nuclear localization signal (NLS), acidic and hydrophobic amino acid (AHAA)-rich region, and death domain (DD), but no ankyrin-repeat (ANK) domain. The BmRelish1t gene was controlled by B. mori cytoplasmic actin 3 promoter in the PiggyBac transposon vector. Chromosome analysis of G1 generations of a transgenic silkworm with EGFP expression confirmed stable insertion of BmRelish1t. BmRelish1t gene overexpression in transgenic silkworms resulted in higher mRNA expression levels of B. mori antimicrobial peptides such as lebocin(~20.5-fold), moricin(~8.7-fold), and nuecin(~17.4-fold) than those in normal silkworms.

• 농촌지도와개발
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• 제28권4호
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• pp.191-202
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• 2021

This study aims to examine agricultural college students' perception of readiness and barriers towards implementation of ICT program. Data were gathered from 175 student of agricultural college in Korea. Descriptive statistics, exploratory and confirmatory factor analysis, t-test, and one-way ANOVA were applied to analyze the data. Results reveal that technology usefulness perception scores were high among the readiness components, but students readiness and school infrastructure readiness were low. Results also shows that policy and technology factors were also seen as the main barriers of ICT program implementation. Findings show that demographic variables did not significantly affect readiness and obstacles. The results of this study can provide guidance to the government or agricultural college organizations when considering readiness and barriers towards implementing ICT programs. In addition, this study contributes to improve the theory of adoption behavior and contributes to the foundation for future research aimed at improving our understanding of agricultural college students' behavior.

• 농촌계획
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• 제9권3호
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• pp.41-46
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• 2003

The study was focused on setting priority for future core technologies in rural development and resources using AHP. The technologies were derived by Delphi method. Evaluation criteria for the priority setting were decided as 'technology', 'market oriented', and 'public concerns' by council. The future core technologies were divided as four groups by importance and R&D level. Technologies in upper two groups were considered in the study. Group I had high importance and high R&D level. Group II had high importance and lower R&D level. Questionnaires were given to 9 specialists in agricultural resources. As the results, 'public concerns' was decided as a most important evaluation criterion. The most important technologies are "technology developing for animal feces and urine treatment, and restoration it to farm land" in group I, and "technology developing for agricultural by-products as energy source" in group II.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2000년도 THE THIRD INTERNATIONAL CONFERENCE ON AGRICULTURAL MACHINERY ENGINEERING. V.II
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• pp.117-123
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• 2000

Using the modified DEM (Discrete Element Method), which we proposed in order to improve the accuracy of the simulation, soil behavior and reaction by lugs of rotating wheel and a soil cutting process by a high speed blade were calculated and compared with experimental data. The DEM is one of computational mechanics, where the object body is supposed as an assembly of small particles called elements and not a continuum as in the case of FEM. We can easily treat some discrete phenomena such as cracking, separating and sliding by the DEM. We had to modify the original mechanical model, which induced too free movement of elements, adding a tension spring, which would display the role of soil adhesion. The results of DEM simulations were successful from both the soil behavior and reaction points of view.

• 한국조리학회지
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• 제20권4호
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• pp.144-156
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• 2014

영양사를 대상으로 학교급식에서 친환경 농산물 사용 확대를 위한 방안 기초자료 제시와 급식의 질과 만족도를 향상시키기 위해 연구 조사하였다. 친환경 우수 농산물 인증에 관한 인지도와 친환경 우수 농산물에 관한 인식간의 요인분석과 Correlation(상관관계분석), 다중회귀분석을 실시하였으며 분석결과는 다음과 같다. 영양사들은 친환경 농산물 인증에 관한 인지도가 그다지 높지 않았으며, 또한 친환경 농산물에 관한 인식과 위험인식은 그다지 높지 않았으나, 친환경 농산물에 관한 지식이 높았으며, 연령과 영양사 경력, 급식인원, 식품비 대비 농산물비로는 별다른 차이를 보이지 않았다. 영양사의 친환경 농산물 인증에 관한 인지도가 높을수록 친환경 농산물에 관한 인지 및 지식이 긍정적인 것으로 나타났으며 친환경농산물 인식은 친환경 우수 농축산물 인증에 관한 인지도에 유의적인 영향을 미치는 것으로 나타났다. 이러한 결과를 통하여 급식의 책임자인 영양사들의 친환경 농산물에 대한 인식을 향상시켜 학교 급식의 질적인 생산성 향상과 급식만족도를 높이도록 하며 학교급식에서의 친환경 농산물 이용도 증가에 따른 영양사뿐만 아니라 학부모의 인식개선도 필요하므로 후속 연구가 필요하다고 사료된다.

• Current Research on Agriculture and Life Sciences
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• 제32권4호
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• pp.171-174
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• 2014

Agriculture in Bangladesh is slowly transforming to the production of high-value fruit and vegetable crops to satisfy the nutrient requirements of their large size population, and this transformation is creating new challenges as regards improving and maintaining the productivity and crop quality. The country has a declining trend of insect pollinators due to habitat loss, land use changes, monoculture-dominated agriculture, and the excessive and indiscriminate use of pesticides. Such pollinator deficiencies can cause reduced yields, thereby threatening the subsistence of marginal farmers. In Bangladesh, growers enjoy free pollination services from the naturally occurring insect populations. While honeybees pollinate mustard, onions, and melons, many other hymenopterans, coleopterans, hemipterans, dipterans, and thysanopterans also visit the crop fields, making these insects significant for the food security, environment, and economy of the nation. Therefore, attention should be given to public policy, research, and human resource development that promotes knowledge and appreciation of the conservation and utilization of insect pollinators.