• Asian-Australasian Journal of Animal Sciences
• /
• 제29권12호
• /
• pp.1719-1724
• /
• 2016

The objective of this study was to determine the effects of physically effective neutral detergent fiber (peNDF) content in total mixed ration (TMR) on dry matter intake, digestibility, and chewing activity in fattening Hanwoo (Bos taurus coreanae) heifers. The experiment was designed as a replicated $3{\times}3$ Latin square using 12 heifers. Fattening heifers were offered one of three diets [high (T1), medium (T2), and low (T3) peNDF] obtained by different mixing times (3, 10, and 25 min) for the same TMR feed. The peNDF content of TMR was determined by multiplying the proportion of dry matter retained by a 1.18 mm-screen in a Penn State Particle Separator by the dietary NDF content. The $peNDF_{1.18}$ content was 30.36%, 29.20%, and 27.50% for the T1, T2, and T3 diets, respectively (p<0.05). Dry matter intake was not affected by peNDF content in TMR. Total weight gain in T1 group was significantly higher (p<0.05) than in T2 and T3 groups. However, weight gain did not differ between T2 and T3 groups. The feed conversion ratio decreased with an increase in the peNDF content (T1: 12.18, T2: 14.17, and T3: 14.01 g/g). An increase in the peNDF content of TMR was associated with a linear increase in the digestibility of dry matter, crude protein, crude fiber, neutral detergent fiber, and acid detergent fiber (p<0.05). Also, an increase in peNDF content of the TMR resulted in a linear increase in the number of chews in eating and ruminating (p<0.05), and consequently in the number of total chews (p<0.05). These results indicate that peNDF content affects digestibility and chewing activity. Consequently, the peNDF content of TMR should be considered for improving feed efficiency, digestibility, body weight gain, and performance in fattening heifers.

• 한국물환경학회지
• /
• 제21권5호
• /
• pp.458-463
• /
• 2005

Considering the characteristics of a filtration bio-reactor equipped with a mesh filter module which can effectively maintain high concentration of biomass and enhanced solid-liquid separation performance, the hybrid process of filtration bio-reactor combined with coagulation was investigated to get improved filtration characteristics as well as water quality in this work. Two bio-reactors (Run-1 & Run-2) were operated under the following conditions: working volume of 25 L, continuous loading of a synthetic wastewater (BOD: 200 mg/L, T-N: 50 mg/L, T-P: 5 mg/L), where an appropriate amount of alum ($Al_2(SO_4)_3{\cdot}18H_2O$) was added once a day into the reactor (Run-2). In the system without using a alum (Run-1), the clogging of mesh filter module was observed two times through 85 days of whole operation. Meanwhile, the filter module did not clog even at higher MLSS concentration (6,000~12,000 mg/L) and the stable filtration (0.7 mid) was continued in the case of using a alum. Due to the stable formation of cake layers, BOD and SS were shown below 6 and 3 mg/L, respectively. T-P and pH of the effluent were changed because of the intermittent addition of the alum. In the case of Al/P=2.5, the average T-P removal efficiency per day was 85.2% and the average T-P concentration of the effluent was 0.3 mg/L. However, the removal efficiency of phosphate was influenced by pH in the reactor.

• 한국생물환경조절학회:학술대회논문집
• /
• 한국생물환경조절학회 1995년도 특강 및 학술논문발표요지
• /
• pp.75-78
• /
• 1995

양액재배시 배양액의 pH는 중요한 재배인자이며, 이는 용수의 성질에 따라 큰 영향을 받는다. 용수로는 지하수를 많이 사용하나, 수돗물을 사용하는 경우도 흔히 있다. 수돗물은 pH가 7.5 정도로, pH가 낮은 용수를 사용할 경우와 같은 조성의 배양액을 조제하면 배양액의 pH가 높아 생육에 나쁜 영향을 끼친다. 따라서, 용수의 성질에 따라 배양액의 조성을 달리하여 pH를 적정수준으로 유지하는 것이 중요하다. (중략)

• 한국수산과학회지
• /
• 제48권5호
• /
• pp.688-695
• /
• 2015

The objective of this study was to investigate the effects of bio-floc system that is composed of effective microorganisms (EM) on the microbial composition and water qualities in rearing water and the growth of Chinese white shrimp, Fenneropenaeus chinensis. To investigate the microbial composition according to the bio-floc levels, the study was conducted at 100 and 150% of bio-floc after 5 and 10 days in bio-floc system. The results showed that total bacteria count (TBC) and the counts of Latobacillus sp., Bacillus sp. and Rhodobactor sp., were significantly decreased after 5 days in bio-floc system. To assess the growth of F. chinensis according to the concentrations of bio-floc, the study was conducted at the bio-floc concentrations; 0 (control), 60, 80, 100, 120 and 140% of the prepared bio-floc for 90 days. The growth factors such as daily length and weight gain were considerably increased at the concentrations of bio-floc 100, 120, and 140% after 90 days. As water quality indicators, the values of total-N, NH₄⁺-N and PO₄^--P were analyzed, and they were significantly decreased at 120 and 140% of bio-floc, compared to the control. The results demonstrated that combination of EM showed the synergic effect on removing N and P.

• 제어로봇시스템학회:학술대회논문집
• /
• 제어로봇시스템학회 2003년도 ICCAS
• /
• pp.90-95
• /
• 2003

In this paper, an Adaptive Nonlinear Constrained Model Predictive Control (ANCMPC) is presented for a pH control in a fed-batch bio-reactor. The pH model is represented with Hammerstein Model. The static nonlinear part of Hammerstein model is described with the static pH model, and the dynamic linear part of the Hammerstein model is described with the CARIMA model. The parameters of the CARIMA model is estimated on-line with the input and output measurements of the system using a recursive least squares type of identi�cation algorithm. The e�ectiveness of the proposed controller is shown through simulations.

• Rapid Communication in Photoscience
• /
• 제2권1호
• /
• pp.31-33
• /
• 2013

The irradiation of electron-beam onto bis-(diphenylphosphino)methane, ethane, propane and butane initiated phenyl-shift from a phosphine to another phosphine atom and subsequent fragmentation resulted in the formation of triphenylphosphine derivative as key intermediate. The mechanism of those processes is speculated.

• 한국생명과학회:학술대회논문집
• /
• 한국생명과학회 2007년도 제48회 학술심포지움 및 추계국제학술대회
• /
• pp.107.2-107.2
• /
• 2007

See Full Text

• Journal of Microbiology and Biotechnology
• /
• 제14권1호
• /
• pp.220-223
• /
• 2004

Club root caused by Plasmodiophora brassicae is found in crucifers. Among the over hundreds of Streptomyces isolated from soil in Korea. One strain showed prominent activity against P. brassicae. The strain was identified based on 16S rDNA sequencing and the morphology by a method of scanning electron microscopy. An active compound in the fermented broth obtained from the strain was separated. Even though the complete assignments of the compound remain for future work, the results regarding the isolation and characterization of the strain with a certain activity against P. brassicae are shown in this paper.

• Molecules and Cells
• /
• 제27권2호
• /
• pp.167-173
• /
• 2009

The classical type of transient receptor potential (TRPC) channel is a molecular candidate for $Ca^{2+}$-permeable cation channels in mammalian cells. Because TRPC4 and TRPC5 belong to the same subfamily of TRPC, they have been assumed to have the same physiological properties. However, we found that TRPC4 had its own functional characteristics different from those of TRPC5. TRPC4 channels had no constitutive activity and were activated by muscarinic stimulation only when a muscarinic receptor was co-expressed with TRPC4 in human embryonic kidney (HEK) cells. Endogenous muscarinic receptor appeared not to interact with TRPC4. TPRC4 activation by $GTP{\gamma}S$ was not desensitized. TPRC4 activation by $GTP{\gamma}S$ was not inhibited by either Rho kinase inhibitor or MLCK inhibitor. TRPC4 was sensitive to external pH with $pK_a$ of 7.3. Finally, TPRC4 activation by $GTP{\gamma}S$ was inhibited by the calmodulin inhibitor W-7. We conclude that TRPC4 and TRPC5 have different properties and their own physiological roles.

• 한국포장학회지
• /
• 제30권2호
• /
• pp.91-100
• /
• 2024

본 연구에서는 총 5종의 T-N, P-N, P-O₂R, P-V 및 P-N₂ 포장방법에 따른 보리새우 오란다의 산가, 과산화물가, 일반세균수, 색도 및 향 성분의 변화를 조사하였다. 산가 및 과산화물가를 분석한 결과, 질소치환 포장기법인 P-N₂ 포장방법을 적용한 보리새우 오란다의 산패가 가장 느리게 진행되는 것으로 확인되었다. 또한, 일반세균수 변화를 분석한 결과, P-N₂ 포장방법을 적용한 보리새우 오란다 내 미생물 성장속도가 감소하는 것을 확인하였다. 색도 변화를 분석한 결과, 포장방법에 따른 유의적인 차이는 크게 없지만, 저장기간이 늘어남에 따라 비효소적 갈변 반응으로 인하여 L^*값은 감소하고, a^*값 및 b^*값은 증가하는 것을 확인하였다. 보리새우 오란다의 향 성분 분석 결과, T-N 포장방법이 적용된 보리새우 오란다의 향 성분은 저장기간에 따라 가장 크게 변화하는 것으로 확인되었다. 5종의 포장방법중, 질소치환 포장방법이 보리새우 오란다의 품질변화 속도를 효과적으로 감소시키는 것을 확인하였다.