• 한국해양학회지:바다
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• 제7권3호
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• pp.181-194
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• 2002

기생은 공생하는 두 생물사이에 한쪽(기생생물)은 이득을 얻는 반면에 다른 한쪽(숙주)은 해를 입는 관계를 말한다. 이러한 기생관계가 생물학적으로 적조를 제어하기 위한 하나의 방법으로서 응용될 수 있으며, 특히 적조생물을 숙주로 하는 기생성 와편모류인 Amoebophrya spp.는 그 잠재력이 큰 것으로 오랫동안 주목받아 왔다. Amoebophrya spp.는 유독성 및 유해성 적조를 일으키는 종을 포함하여 24속 40여종 이상의 와편모류들을 감염시킬 수 있는 것으로 알려져 있다 기생성 와편모류 Amoebophrya는 포자(dinospore)의 분산 및 감염 단계,감염 후 숙주 세포내에서 성장단계 (trophont), 그리고 숙주 세포 밖의 생식단계(vermiform) 등의 간단한 생활사를 가지고 있다. 최근의 연구결과에 의하면, 분산 및 감염을 담당하는 dinospore는 각 숙주-기생생물 관계에 따라 감염능력, 생존능력 및 감염 성공률 등 서로 다른 생물학적 차별성을 보인다. 각 숙주기생생물 관계 기원 dinospores의 서로 다른 생물학적 특성, 교차 감염실험 및 분자생물학적 연구결과 등으로 보아 Amoebophrya ceratil가 숙주 특이성이 없는 단일종이라는 이전의 주장보다는 아마도 숙주 특이성을 갖고 있는 여러 분류군으로 구성된 종 복합체 (species complex)라는 가설이 타당하다. 숙주 와편모류들은 기생성 와편모류 Amoebophrya에 의해 일단 감염되고 나면 더 이상 성장하지 못하고 생식능력을 잃고 모두 사망하게 되는데, 이 감염 과정동안 해당 플랑크톤 생태계에 대한 영향은 다양하게 나타난다. 독립영양성 와편모류들이 감염될 경우 그들의 광합성 능력이 크게 영향을 받으며, 감염위치(핵 또는 세포질)에 따라서 영향받는 속도가 다르다. 이 기생성 와편모류에 의한 감염은 광주성 및 유영속도 등에 영향을 미쳐서 숙주 와편모류의 일주 수직이동 양상과 같은 동태에도 커다란 영향을 끼칠 수 있다. 기생성 와편모류의 감염으로 인한 숙주의 사망은 자연 사망할 때보다 시간적으로 더 빨리 숙주로부터 다량의 유기물이 방출되게 할 수 있을 뿐만 아니라, 기생생물에 의한 감염은 감염기간 동안에도 숙주로부터 상당한 양의 용존 유기물이 인위적으로 방출되게 할 가능성이 있다. 기생생물에 감염시에는 상대적으로 크기가 큰 숙주 와편모류의 생체량이 사망과 동시에 크기가 작은 수많은 포자들로 생물학적 전환이 일어나고, 이어서 이들 포자들은 섬모류 등의 포식자들에게 먹이로서 이용i소화될 수 있으므로, 숙주 와편모류가 지녔던 물질과 에너지가 미소생물고리내에서 보다 오랜기간 동안 머무를 수 있는 가능성이 더욱 커질 것으로 생각된다 다양한 숙주-기생생물 관계에 대하여 다양한 물리, 화학적 환경요인과 여타의 생물학적 요인들이 어떠한 영향을 미치는지에 대한 보다 심도있는 연구는 플랑크톤 생태학과 적조역학에서 기생성 와편모류의 역할을 보다 잘 이해하도록 하는데 기여할 것으로 기대된다.

• Asian-Australasian Journal of Animal Sciences
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• 제14권9호
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• pp.1260-1266
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• 2001

The effect of protein supplementation, $O_2$ concentration and co-culture on the development of embryos produced by nuclear transfer using cultured cumulus cell was investigated. Recipient oocytes and cumulus cells were obtained from the ovaries of the slaughtered Hanwoo cows. Donor cumulus cells were cultured in Dulbecco's modified Eagle medium containing 10% fetal bovine serum at 5% $CO_2$ in air at $38.5^{\circ}C$. The 1 to 6 passages of cumulus cells were isolated and used as donor cells. The in vitro matured oocytes were enucleated and then the isolated donor cells were introduced. One $15{\mu}s$ pulse of 180 volts was applied to induce the fusion between karyoplast and cytoplast. The fused embryos were activated with $10{\mu}M$ calcium ionophore for 5 min and 2 mM 6-dimethylaminopurine for 3 h. To examine the effect of protein supplementation, nuclear transfer (NT) embryos were cultured in one of the following 4 treatments : 1) CR1aa + 3 mg/ml BSA for 7 days ; 2) CR1aa + 10% FBS for 7 days ; 3) CR1aa + 1.5 mg/ml BSA + 5% FBS for 7 days ; and 4) CR1aa + 3 mg/ml BSA for first 3 days and then CR1aa + 1.5 mg/ml BSA + 5% FBS for 4 days. Culture took place at 5% $CO_2$, 5% $O_2$ and 90% $N_2$ at $38.5^{\circ}C$. Although there were no significant differences in cleavage rate among different protein supplements, the rates of blastocyst formation were significantly different. When NT embryos were cultured in the medium supplemented with only BSA, they could develop to only morula not to blastocyst. However, when FBS was supplemented, NT embryos developed to blastocyst stage. In order to investigate the effect of $O_2$ concentration and co-culture, NT embryos were cultured in CR1aa + 1.5 mg/ml BSA + 5% FBS with or without cumulus cell co-culture at an atmosphere of 5% $CO_2$ in air (20% $O_2$) or 5% $CO_2$, 5% $O_2$, 90% $N_2$ (5% $O_2$) at $38.5^{\circ}C$ for 7 days. The percentage of blastocyst development was significantly higher when the NT embryos were cultured at an atmosphere of 5% $O_2$ than that of 20% $O_2$ (p<0.05). However, there was no significant difference between with and without cumulus cell co-culture at an atmosphere of 5% $O_2$ or 20% $O_2$. Fifty embryos were transferred to 25 recipients and 5 recipients were pregnant at 100 days. From 5 pregnant cows, only one cow was delivered of female twin. In conclusion, the embryos reconstructed by enucleation of metaphase II oocytes and introduction of the cycling and quiescent cumulus donor cells in Hanwoo had developmental potential to term after embryo transfer to recipient cows.

• Asia pacific journal of information systems
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• 제17권3호
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• pp.105-130
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• 2007

Recently, there is a substantial interest in implementing Business Process Management System(BPMS) among enterprises with the purpose of business process innovation. BPMS redesigns and coordinates business processes in terms of both automated steps and human involvement in order to maximize the value of both involved people and systems. The reason why BPMS is getting attention from top managers is that it has the possibility to optimize the business processes by cycling the process of modeling, execution, monitoring, evaluation, and redesigning work processes. Thus, it has created high expectations about not only productivity improvement but also business process innovation. However. having an innovative nature, which is used for process innovation, BPMS implementation has great potential to stir up employee resistance. The analysis and the discussion about the prevention of the resistance against IS(Information Systems) is important because IS change the way people work and also alter the power structure within the organization, in general. The purpose of this study is to investigate factors that have an impact on the effective adoption of BPMS at the enterprise level. To find out these factors, this study considers two characteristics of BPMS: First. BPMS shares some characteristics with other enterprise-wide IS such as ERP. Second, it has special BPMS-specific characteristics. Due to the lack of previous research on BPMS adoption, interviews were carried out with IT-consultants and CIOs who conducted BPMS projects previously to find out BPMS-specific features that would make BPMS unique when compared to other enterprise-wide IS. As a result, the monitoring function was chosen as the main BPMS-specific factor. Thus, this paper reviewed studies both on enterprise-wide IS adoptions, which applied Technology Acceptance Model (TAM) and secondly on computer based monitoring to find out factors that would influence the employees' perception on the monitoring function of BPMS. Based on the literature review, the study suggested three factors that would have an impact on the employee's perception of the monitoring function: fairness of enterprise evaluation system, fairness of the boss, and self-efficacy of their work. Three factors that would impact the enterprise-wide IS adoption were also set: the shared belief in the benefit of BPMS, training, and communication. Then, these factors were integrated with TAM. Structural equation modeling was used to test hypotheses, out factors that would impact the employees' perception on the monitoring function of BPMS. Based on the literature review the study suggested three factors that would have an impact on the employee's perception of the monitoring function: fairness of enterprise evaluation system, fairness of the boss, and self-efficacy of their work. Three factors that would impact the enterprise-wide IS adoption were also set: the shared belief in the benefit of BPMS, training, and communication. Then, these factors were integrated with TAM. Structural equation modeling was used to test hypotheses. The data analysis results showed that two among three monitoring function related factors - enterprise evaluation system and fairness of the boss - were significant. This implies that employees would worry less about the BPMS implementation as long as they perceive the monitoring results will be used fairly for their performance evaluation. However, employees' high self-efficacy on their job was not a significant factor in their perception of the usefulness of BPMS. This is related to cases that showed employees resisted against the information systems because they automated their works (Markus, 1983). One specific case was an electronic company, where the accounting department workers were requested to redefine their job because their working processes were automated due to BPMS implementation.

• 한국가축번식학회지
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• 제24권1호
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• pp.49-57
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• 2000

본 연구는 소 태아섬유아세포를 이용하여 핵이식 후 세포의 휴면처리, 세포의 passage 수 및 세포의 기원이 복제란의 발육에 미치는 영향을 검토하였다.3.57개 월령 한우 수컷 태아의 피부 및 간 조직에서 세포를 채취하여 체외에서 4∼6 회 계대배양 후 동결하였다가 핵이식에 사용하였다. 세포는 핵이식 전에 혈청기아처리를 하였으며, 대조구로는 활발히 분열 중의 무처리 세포를 사용하였다. Donor 세포는 미수정란의 탈핵세포질에 이식 후 전기융합 및 활성화를 실시하였고, 재구축배는 7∼9 일간 체외배양하여 발육농을 검토하였다. 배반포로 발육된 일부 복제란은 발정 7∼8 일째의 수란우에 이식하였다. 복제란의 배반포 발육율은 혈청기아 처리구 (25.3%)가 무처리구 (15.9%)에 비하여 유의적으로 높았으나 (P＜0.05), 세포의 passage 수 (4∼6회) 에 관계없이 23.1∼25.0%로 나타났고, 피부 및 간유래 복제란의 배반포 발육율도 23.8∼25.2% 로 두 조직세포 간에 차이가 없었다. 복제란의 이식 후 60일 및 120일에 수란우의 34.4% 및 15.6%가 각각 임신이 확인되었으며, 초자화동결된 태아 피부세포 복제란으로부터 1두의 수컷 송아지가 생산되었다. 본 연구의 결과는 복제란의 체외발육능이 세포의 휴면처리에 의하여 향상되었으나, 세포의 passage 수 (4∼6 회) 및 세포의 두 기원 (피부 및 간) 에 의해서는 영향을 받지 않으며, 태아 피부세포 유래 복제란으로부터 산자가 생산될 수 있음을 확증한다.