• Asian-Australasian Journal of Animal Sciences
• /
• 제28권7호
• /
• pp.1006-1013
• /
• 2015

Heat-stress remains a costly issue for animal production, especially for poultry as they lack sweat glands, and alleviating heat-stress is necessary for ensuring animal production in hot environment. A high ${\gamma}$-aminobutyric acid (GABA)-producer Lactobacillus strain was used to investigate the effect of dietary GABA-producer on laying performance and egg quality in heat-stressed Hy-line brown hens. Hy-Line brown hens (n = 1,164) at 280 days of age were randomly divided into 4 groups based on the amount of freeze-dried GABA-producer added to the basal diet as follows: i) 0 mg/kg, ii) 25 mg/kg, iii) 50 mg/kg, and iv) 100 mg/kg. All hens were subjected to heat-stress treatment through maintaining the temperature and the relative humidity at $28.83{\pm}3.85^{\circ}C$ and 37% to 53.9%, respectively. During the experiment, laying rate, egg weight and feed intake of hens were recorded daily. At the 30th and 60th day after the start of the experiment, biochemical parameters, enzyme activity and immune activity in serum were measured. Egg production, average egg weight, average daily feed intake, feed conversion ratio and percentage of speckled egg, soft shell egg and misshaped egg were significantly improved (p<0.05) by the increasing supplementation of the dietary GABA-producer. Shape index, eggshell thickness, strength and weight were increased linearly with increasing GABA-producer supplementation. The level of calcium, phosphorus, glucose, total protein and albumin in serum of the hens fed GABA-producing strain supplemented diet was significantly higher (p<0.05) than that of the hens fed the basal diet, whereas cholesterol level was decreased. Compared with the basal diet, GABA-producer strain supplementation increased serum level of glutathione peroxidase (p = 0.009) and superoxide dismutase. In conclusion, GABA-producer played an important role in alleviating heat-stress, the isolated GABA-producer strain might be a potential natural and safe probiotic to use to improve laying performance and egg quality in heat-stressed hens.

• 한국연초학회지
• /
• 제4권2호
• /
• pp.11-16
• /
• 1982

To investigate the effect of reciprocal grafting between Hyangchio (H) and L. A. Burley 21 (L.A), one a higher producer of nicotine and low yield, the other, a low producer of nicotine and high yield, growth of various parts of each variety and chemical constituents of these parts were evaluated. The results were as follows : The growth of H/H graft was depressed when compared to hyangchio and H/L. A. and L. A. Burley 21 showed most vigorous growth plants having L. A. Burley 21 top. The amount of total alkaloids were low in leaves and stems of plants having L. A. Burley 21 roots (L. A., L. A./L. A., H/L. A.). Plants having Hyangchio roots (H, L. A./H) were high in total alkaloids. The contents of reducing sugar were high in plant having Hyangchio top compared to L. A. Burley 21 tops, but there were not diffences in contents of ether extracts among all treatments.

• 한국작물학회지
• /
• 제47권
• /
• pp.135-139
• /
• 2002

The standard of quality was required to promote the consumption of potato and produce the high quality processing products. It will contribute the stability for processing products and the marketability of potato. The quality was determined based on size of tuber and content of dry matter. Even though the criteria of potato quality was involved many characters of tubers, the most important things were grading and packing of potato to create the consumption. For processing of raw materials, the standard of tubers had create between producer and processor according to size of tuber and content of dry matter. The evaluation of quality was performed over the standard to enhance the control of quality. In addition, the seed potato should be taken the evaluation to disease in the field during the period of cultivation and managed under the strict regulation in storage before release to farmer. Then, the producer of seed potato will make a good relationship to farmer with high quality tubers.

• Journal of Microbiology and Biotechnology
• /
• 제19권2호
• /
• pp.136-139
• /
• 2009

Avermectin and its analogs are major commercial antiparasitic agents in the fields of animal health, agriculture, and human infections. Previously, comparative transcriptome analysis between the low-producer S. avermitilis ATCC31267 and the high-producer S. avermitilis ATCC31780 using a S. avermitilis whole genome chip revealed that 50 genes were overexpressed at least two-fold higher in S. avermitilis ATCC31780. To verify the biological significance of some of the transcriptomics-guided targets, five putative regulatory genes were individually cloned under the strong-and-constitutive promoter of the Streptomyces expression vector pSE34, followed by the transformation into the low-producer S. avermitilis ATCC31267. Among the putative genes tested, three regulatory genes including SAV213, SAV3818, and SAV4023 exhibited stimulatory effects on avermectin production in S. avermitilis ATCC31267. Moreover, overexpression of SAV3818 also stimulated actinorhodin production in both S. coelicolor M145 and S. lividans TK21, implying that the SAV3818, a putative TetR-family transcriptional regulator, could be a global upregulator acting in antibiotic production in Streptomyces species.

• KSBB Journal
• /
• 제13권3호
• /
• pp.331-335
• /
• 1998

Erythritol is a four-carbon sugar alcohol with a low calorific value and non-cariogenicity. Erythritol is a new functional sweetener which can be used as sugar alternative. Erytheitol dose not cause discomfort such as diarrhoea and flatulence upon ingestion. The purpose of this study is to develope a novel process of erythritol economically in a large scale. To obtain a high erythritol producer, we have screened 3500 colonies from molasses, honey and honey combs. We have selected 40 erythritol-producing microorganisms, one of which yields 140g/L erythritol in 40% glucose medium. We have tested this strain in 5L fermentor to examine the fermentation characteristics. Results of fermentation show that the erythritol production was about 1.4g/L$.$hr in 400g/L glucose media with a 42% conversion. Further improvements require mutation for a higher producer, process optimization to reduce glycerol, and suppression of excessive foaming.

• International Journal of Reliability and Applications
• /
• 제17권1호
• /
• pp.85-105
• /
• 2016

In this paper accelerated life testing is incorporated in quality control technique of acceptance sampling plan to induce early failures in high reliability products.Stress under accelerated condition can be applied in constant-stress, step-stress and progressive-stress or combination of such loadings. A ramp-stress results when stress is increased linearly (from zero) with time. In this paper optimum failure-censored ramp-stress accelerated life test sampling plan for log-logistic distribution has been formulated with cost considerations. The log-logistic distribution has been found appropriate for insulating materials. The optimal plans consist in finding optimum sample size, sample proportion allocated to each stress, and stress rate factor such that producer's and consumer's interests are safeguarded. Variance optimality criterion is used when expected cost per lot is not taken into consideration, and bilevel programming approach is used in cost optimization problems. The methods developed have been illustrated using some numerical examples, and sensitivity analyses carried out in the context of ramp-stress ALTSP based on variable SSP for proportion nonconforming.

• 한국유기농업학회지
• /
• 제11권2호
• /
• pp.43-60
• /
• 2003

Recently. together with consumers' increasing concerns on food safety and environmental issues. there is increasing demand on the environmentally friendly agricultural products such as organic products. At present, Japan. as a biggest net importing country of the agricultural products. is a market of the international-scale in the organic product marketing. Also. it is expected that the possibility of market expansion in the future is very high. According to the 2000 agricultural census in Japan. the number of the environment-friendly agricultural farmers were 501.556 householders. This number is about 145 percent higher than that of the 1996 results of 204,600 householders. Organic products in Japan were mainly marketed through the producer and consumer cooperation, producers' cooperation, specialized marketing company etc. However, along with the department store, big supermarket and others' participation in the market recently, the marketing channels are diversified. As of October 1999, market sales of the organic products were estimated about 350 billion yen. It is expected that organic certification system, organic products import, resturant industry scale and others will be more influential factors on the market expansion of the organic products in the future.

• Journal of Microbiology and Biotechnology
• /
• 제16권11호
• /
• pp.1690-1698
• /
• 2006

In order to investigate the effect of dissolved oxygen (DO) level on AVM $B_{1a}$ production by a high yielding mutant of Streptomyces avermitilis, five sets of bioreactor cultures were performed under variously controlled DO levels. Using an online computer control system, the agitation speed and aeration rate were automatically controlled in an adaptive manner, responding timely to the oxygen requirement of the producer microorganism. In the two cultures of DO limitation, the onset of AVM $B_{1a}$ biosynthesis was observed to casually coincide with the fermentation time when oxygen-limited conditions were overcome by the producing microorganism. In contrast, this phenomenon did not occur in the parallel fermentations with DO levels controlled at around 30% and 40% throughout the entire fermentation period, showing an almost growth-associated mode of AVM $B_{1a}$ production: AVM $B_{1a}$ biosynthesis under the environments of high DO levels started much earlier than the corresponding oxygen-limited cultures, leading to a significant enhancement of AVM $B_{1a}$ production during the exponential stage. Consequently, approximately 6-fold and 9-fold increases in the final AVM $B_{1a}$ production were obtained in 30% and 40% DO-controlled fermentations, respectively, especially when compared with the culture of severe DO limitation (the culture with 0% DO level during the exponential phase). The production yield ($Y_{p/x}$), volumetric production rate (Qp), and specific production rate (${\bar{q}}_p$) of the 40% DO-controlled culture were observed to be 14%, 15%, and 15% higher, respectively, than those of the parallel cultures that were performed under an excessive agitation speed (350 rpm) and aeration rate (1 vvm) to maintain sufficiently high DO levels throughout the entire fermentation period. These results suggest that high shear damage of the high-yielding strain due to an excessive agitation speed is the primary reason for the reduction of the AVM $B_{1a}$ biosynthetic capability of the producer. As for the cell growth, exponential growth patterns during the initial 3 days were observed in the fermentations of sufficient DO levels, whereas almost linear patterns of cell growth were observed in the other two cultures of DO limitation during the identical period, resulting in apparently lower amounts of DCW. These results led us to conclude that maintenance of optimum DO levels, but not too high to cause potential shear damage on the producer, was crucial not only for the cell growth, but also for the enhanced production of AVM $B_{1a}$ by the filamentous mycelial cells of Streptomyces avermitilis.

• 한국지역지리학회지
• /
• 제18권3호
• /
• pp.298-309
• /
• 2012

본 연구에서는 중국 베이징시(북경시(北京市)) 중관촌(中關村) 클러스터를 사례로 첨단산업 네트워크의 공간적 특성을, 구매, 판매, 생산자 서비스, 정보, 연구개발에 초점을 두고 고찰하였다. 분석결과는 다음과 같다. 중관촌(中關村) 클러스터 기업의 구매, 생산자 서비스, 정보, 연구개발 네트워크의 공간적 특성은 클러스터 내부를 중심으로 하는 국지적 네트워크가 발달하고 지역적 뿌리내림이 강하게 나타났다. 이는 중관촌(中關村) 클러스터 기업은 중국을 대표하는 첨단 기업으로 원자재 및 부품은 클러스터 내 기업에 주로 의존할 수밖에 없는 산업환경적 특성과 정부의 정책적 지원 기관이 집중되어 있기 때문에 생산자 서비스 그리고 혁신에 관한 정보를 제공할 수 있는 제도적 기반이 상대적으로 잘 갖추어져 있기 때문이다. 또한 중관촌(中關村) 클러스터는 중국 내 타 지역에 비해 우수한 연구개발 역량을 가진 기업, 대학, 그리고 연구소가 집적되어 있을 뿐만 아니라 클러스터 내에 기술혁신을 위한 각종 지원기관이 집중되어 양적으로나 질적으로 최고수준의 연구개발 지원을 받고 있기 때문이다. 반면에 이 지역에서 생산된 첨단 제품들은 베이징뿐만 아니라 중국 전역 나아가서는 해외로 판매되고 있기 때문에 제품 판매 네트워크는 비국지적 네트워크가 강하다. 결론적으로 특정산업집적지가 혁신클러스터로 발전함에 있어서는 클러스터 주체간의 국지적 네트워크의 강화가 무엇보다 중요하다. 이런 점에서 중관촌(中關村) 클러스터는 네트워크 관점에서 본다면 기본적인 토대가 갖추어졌다고 할 수 있다. 그러나 국제적인 경쟁력을 강화하기 위해서는 국지적 네트워크뿐만 아니라 국제적 네트워크를 강화할 필요가 있다고 하겠다.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
• /
• pp.638-644
• /
• 1999

Workability time of superplasticized concrete is maintained generally for 30-60 minutes only. Therefore it is of great advantage for the concrete producer to use a high range water reducer which provides an extended slump life. Recently slump retentive srperplasticizer has been developed. Concrete mixing tests were done to know slump, setting, air content, bleeding and hardening characteristics of concrete using slump retentive superplasticizer. With slump retentive superplasticizer, high quality concrete was produced and slump loss of concrete was reduced in big way, making long transportation time possible as a practical alternative to on-site addition.