• 제목/요약/키워드: 생존성 평가

검색결과 731건 처리시간 0.033초

Dual Coating Improves the Survival of Probiotic Bifidobacterium Strains during Exposure to Simulated Gastro-Intestinal Conditions (위장관내 조건에서 이중코팅 처리 된 프로바이오틱 비피도박테리움의 생존력 향상)

  • Kang, Joo Yeon;Lee, Do Kyung;Park, Jae Eun;Kim, Min Ji;Lee, Joong-Su;Seo, Jae-Gu;Chung, Myung Jun;Shin, Hea Soon;Ha, Nam Joo
    • Korean Journal of Microbiology
    • /
    • 제49권3호
    • /
    • pp.275-281
    • /
    • 2013
  • Probiotics have been reported to benefit human health by modulating immunity, lowering cholesterol, improving lactose tolerance, and preventing some cancer. Once ingested, probiotic microorganisms have to survive harsh conditions such as low pH, protease-rich condition, and bile salts during their passage through the gastro-intestinal (GI) tract colonize and proliferate to exert their probiotic effects. The dual coating technology, by which the bacteria are doubly coated with peptides and polysaccharides in consecutive order, was developed to protect the ingested bacteria from the harsh conditions. The aim of the study was to evaluate the viable stability of a doubly coated blend of four species of Bifidobacterium by comparing its bile/acid resistance and heat viability in vitro with that of the non-coated blend. After challenges with acid, bile salts, heat, and viable cell counts (VVCs) of the dual coated and non-coated blend were determined by cultivation on agar plates or flow cytometric measurement after being stain with the BacLigtht kit$^{TM}$. The results showed that the dual coated blend was much higher resistant to the acidic or bile salt condition than the non-coated blend and heat viability was also higher, indicating that the dual coating can improve the survival of probiotic bacteria during their transit through the GI tract after consumption.

Evaluation of Extended Boar Semen after Glass Wool Filtration (Glass Wool Filtration 후 돼지정액의 평가)

  • Kang, Tae-Young
    • Journal of Veterinary Clinics
    • /
    • 제32권1호
    • /
    • pp.45-48
    • /
    • 2015
  • The purpose of this study was to select high-quality boar semen after the glass wool filtration of extended boar semen. After collecting boar semen, its concentration, morphology, viability, and motility were examined according the glass wool's height and time. After glass wool filtration, the sperm concentration decreased, but the proportion of normal sperms and the sperm viability increased. Nevertheless, the sperm motility showed no changes. The above results showed that the glass wool filtration of boar semen is a method of obtaining sperms with relatively low abnormal rates and high viabilities.

Assessment of Self-sealing Performance of the Fuel Tank of the Rotorcraft against Gunfire Projectiles (회전익 항공기용 연료탱크 내탄성능 시험평가)

  • Kim, Hyun-Gi;Kim, Sung-Chan;Lee, Jong-Won;Hwang, In-Hee;Hue, Jang-Wook;Shin, Dong-Woo;Jung, Tae-Kyung;Ha, Byoung-Geun
    • Journal of the Korean Society for Aeronautical & Space Sciences
    • /
    • 제38권5호
    • /
    • pp.477-481
    • /
    • 2010
  • Some rotorcraft fuel tanks are required to be self-sealing and crashworthy for enhancing the survivability of crews. Self-sealing capability prevents the fuel leakage through contacting fuel with self-sealing material when the tank wall is penetrated by projectiles such as bullets. US army established MIL-DTL-27422D which specifies the detail requirements related to gunfire resistant fuel tank especially for military rotorcraft. The Fuel tanks for Korea Helicopter Program have been developed in accordance with MIL-DTL-27422D. The Self-sealing capability of the fuel tanks has been confirmed by the gunfire resistance test which specified on the MIL-DTL-27422D.

How Entrepreneur Competency Impacted Startup Survival During the COVID-19 Pandemic: The Mediating Role of Business Performance (코로나19 팬데믹 기간 창업자 역량이 창업기업의 생존에 미치는 영향: 경영 성과의 매개 역할)

  • Kim, Bongkeun;Yoo, Bumjoon;Hwangbo, Yun;Kim, YoungJun
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • 제19권3호
    • /
    • pp.155-172
    • /
    • 2024
  • The COVID-19 pandemic not only posed an enormous human crisis, but also had a profound impact on firms' survival. Social distancing and global lockdown measures designed to protect human lives have paradoxically impaired the business environment. As a result, firms that sought to gain competitive advantage by leveraging external resources were cut off from the external world and faced unexpected challenges. Under these circumstances, researches were conducted in the early stage of the pandemic to explore how certain firms survived while others fell, but they were limited to re-examining business performance using traditional financial factors. However, this study aims to investigate the role of entrepreneurs' competency in crisis situations from the Resource-Based View (RBV), as such competency plays an important role in improving business performance and subsequently the probability of startups' survival. Specifically, we evaluated the performance as of end of 2019 of 1,127 startups evaluated by the Korea Technology Finance Corporation (KOTEC), which provides policy financing based on technology assessment, in 2016. We then conducted an empirical study to determine the mediating role of business performance in the relationship between entrepreneurial competencies and firm survival by verifying how many of the sample firms were still in operation at the end of June 2023, when the Korean government declared COVID-19 as an endemic. For this purpose, we defined technological, financial, and marketing competencies as the sub-factors of entrepreneurial competency, and sales growth rate and employment growth rate as the sub-factors of business performance. The results of the empirical analysis showed that technological and financial competencies of the entrepreneur had a positive impact on both business performance and firm survival, and that sales growth rate and employment growth rate mediated the relationship between technological competence and firm survival. However, the positive influence of entrepreneurs' financial competence of the survival of startups was only evident through the growth of employment. This study is the first study in South Korea to define the survival factors of startups in the context of the COVID-19 pandemic, and is expected to contribute to the theoretical and practical discussions on the importance of entrepreneurs' competency as a firms' survival factor based on RVB.

  • PDF

A Study on Reliability Estimation for Electricity Meter and Digitall Protection Relay (전자석 계량/계전기의 신뢰성평가 방법 연구)

  • Lee, D.H.;Lee, Y.H.;Sin, Y.S.;Kim, Y.K.;Sin, Y.J.;Kim, M.;Park, Jeong-Won
    • Proceedings of the KIEE Conference
    • /
    • 대한전기학회 2005년도 추계학술대회 논문집 전력기술부문
    • /
    • pp.3-5
    • /
    • 2005
  • 21세기의 무한 경쟁 환경에서 기업의 생존은 고객 만족에 의해 좌우된다고 해도 과언이 아니다. 한편, 고객 만족을 달성하기 위해서는 고객의 욕구가 어떻게 변화하고 있는가를 충실히 파악하여야 한다. 헌재의 고객은 제품의 기본 기능과 가격 똥의 요소뿐만 아니라, 제품의 품질, 특히 신뢰성에 매우 민감한 반응을 보이고 있으며, 각 기업은 이러한 추세를 반영하여 제품의 보증기간을 경쟁적으로 연장하고 있다. 신뢰성이란 제품이 얼마나 오랫동안 고장 없이 의도한 기능을 발휘할 수 있는가를 나타낸다. 즉, 신뢰성이란 시간적 품질을 의미하며 제품이 충분한 신뢰성을 가지고 있지 못할 경우, 과도한 클레임으로 인한 보증비용의 증가와 같은 단기적인 손해뿐만 아니라, 고객 불만족, 고객 이탈, 기업 경쟁력 상실 통으로 야기되는 장기적인 손실에 이르기까지 매우 큰 피해를 감수해야 한다. 따라서 제품의 신뢰성은 기업의 생존과 경쟁력 우위를 확보하기 위한 중요한 전략적 요소로 다루어 져야 한다. 신뢰성 활동은 크게 신뢰성 평가와 신뢰성 설계 두 가지로 나눌 수 있다. 전자는 현재 개발 또는 양산 중인 제품의 신뢰성 수준이 어느 정토인가를 파악하자 하는 활동이며, 후자는 제품에 신뢰성을 높이기 위한 일련의 활동을 포함한다. 한편, 신뢰성 평가는 모든 신뢰성 업무에서 앞서 선행적으로 이루어 져야 하는 기초적 활동이며, 본 과제에서는 자사의 전자식 전력량계(LSEW12)와 디지털 보호계전기(GIPAM2200)를 대상으로 신뢰성 평가에 관한 연구를 수행하였다.

  • PDF

Effect of Evasive Maneuver Against Air to Air Infrared Missile on Survivability of Aircraft (공대공 적외선 위협에 대한 회피기동이 항공기 생존성에 미치는 영향)

  • Bae, Ji-Yeul;Bae, Hyung Mo;Kim, Jihyuk;Jung, Dae Yoon;Cho, Hyung Hee
    • Journal of the Computational Structural Engineering Institute of Korea
    • /
    • 제30권6호
    • /
    • pp.501-506
    • /
    • 2017
  • An infrared seeking missile does not emit any signal by itself as it is guided by passive heat signature from an aircraft. Therefore, it is difficult for the target aircraft to notice the existence of incoming missile, making it a serious threat. The usage of MAW(missile approach warning) that can notify the approaching infrared seeking missile is currently limited due to its high cost. Furthermore, effectiveness of MAW against infrared seeking missile is not available in open literature. Therefore, effect of evasive maneuver by MAW on the survivability of the aircraft is simulated to evaluate the benefit of the MAW in this research. The lethal range is used as a measure of aircraft survivability. An aircraft flying at an altitude of 5km with Mach 0.9 being tracked by air-launched AIM-9 infrared seeking missile is considered in this research. As a variable for the evasive maneuver, the MAW recognition distance of 5~7km and the G-force of 3~7G that limits maximum directional change of the aircraft are considered. Simulation results showed that the recognition of incoming missile by MAW and following evasive maneuver can reduce the lethal range considerably. Maximum reduction in lethal range is found to be 29.4%. Also, the MAW recognition distance have a greater importance than the aircraft maneuverability that is limited by structural limit of the aircraft.

유전독성물질의 평가방법과 그 기작에 관한 연구

  • 이정섭;박종근;박종광;박상대
    • Proceedings of the Korean Society of Applied Pharmacology
    • /
    • 한국응용약물학회 1993년도 제2회 신약개발 연구발표회 초록집
    • /
    • pp.170-170
    • /
    • 1993
  • 유전독성물절외 검출과 평가에 용이하게 사용할 수 있는 모델 시스템의 개발 및 DNA 회복기작을 규명할 목적으로 수종의 돌연변이, 발암원을 이용하여 배양 포유동물세포 및 어류세포에서 세포생존률, DNA 합성 및 복제억제의 양상 등을 비교 분석하였다. MMS및 MNNG 와 같은 알칼라제는 CHO 세포에서 유의한 DNA 합성저해, DNA 복재억제, DNA 단사절단 및 비주기성 DNA 합성률의 증가를 유발하였다. Benzo(a)pyrene과 3-methylcholanthrene좌 같은 DNA 상해 전구물질의 경우 유전독성 여부의 판정에는 반드시 S-9/15과 같은 대사활성계 또는 mouse embryonic fibroblast와 같은 대사 활성능이 있는 세포와의 co-culture system들이 필요함을 확인하였으며, 이들에 의한 DNA 상해와 복재억제 유도의 작용양상은 자외선의 작용양상과 유사하였다. 배양 어류세포에서 자외선에 의한 세포생존율의 측정, 광재활성능의 분석 및 자외선에 의해 유발된 피리미딘 이량체 절제능 검토 및 DNA 합성 저해능의 결과를 분석함으로써 유전독성 평가를 위한 모델 시스템 구축의 기초결과를 얻었다.

  • PDF

Surgical Outcome of Patients with Ischemic Cardiomyopathy Selected by the Results of Myocardial Viability by Preoperative F-18 FDG PET (F-18 FDG 양전자단층촬영을 이용한 생존심근 평가 후 수술한 허혈성 심근병증 환자의 수술 결과)

  • Kim, Jae-Sung;Lee, Dong-Soo;Hong, Suk-Keun;Lee, Young-Tak;Kim, Yu-Kyeong;Kim, Youn-Jung;Moon, Keon-Sik;Won, Tae-Kyoung;Hwang, Hweung-Kon
    • The Korean Journal of Nuclear Medicine
    • /
    • 제34권4호
    • /
    • pp.276-284
    • /
    • 2000
  • Purpose: We investigated the operative outcome after bypass surgery in patients selected using viability criteria on F-18 FDG PET. Materials and Methods: Rest-24hr delay redistribution imaging of Tl-201 SPECT and F-18 FDG PET were performed in 11 patients. Seven of these 11 patients (6 men, 1 woman) were evaluated to have viable myocardium by F-18 FDG PET. Changes in symptoms and left ventricular ejection fraction (LVEF) after operation were evaluated. Results: In seven of 11 patients, a significant amount of viable myocardium was found on F-18 FDG PET and Tl-201 SPECT. Severity of both chest pain and dyspnea improved markedly in all patients. Mean LVEF improved from 22% to 32%. Conclusion: F-18 FDG PET could be used to select the patients who will benefit from coronary artery bypass surgery.

  • PDF

Retrospective study on survival rate of 2158 osseointegrated implants placed in 770 patients in Sanbon dental hospital of Wonkwang University (원광대학교 산본치과병원에서 770명의 환자에 식립한 2158개의 골유착성 임플란트의 보철 전 초기 생존율에 관한 후향적 연구)

  • Seon, Hwa-Gyeong;Chee, Young-Deok
    • Journal of Dental Rehabilitation and Applied Science
    • /
    • 제30권4호
    • /
    • pp.278-288
    • /
    • 2014
  • Purpose: The aim of the study was to evaluate preprosthetic initial survival rate and factors associated with survival of osseointegrated implants placed in edentulous area of maxilla and mandible and to suspect the possible causes leading to failure. Materials and Methods: A total of 2158 endosseous implants that had been inserted between 2004 through 2013 were placed in 770 patients. The clinical comparisons were performed to evaluate implant loss in relation to age and gender of patients, position, system, length and diameter of implant, and bone graft technique. Results: According to position, the survival rates were 98.23% in maxillary anterior site, 96.98% in maxillary posterior site, 97.85% in mandibular anterior site and 98.76% in mandibular posterior site (P < 0.05). According to diameter of implant, the survival rates were 100% under 3.0 mm, 97.09% between 3.0 to 3.5 mm, 98.19% between 3.5 to 4.0 mm and 98.29% between 4.0 to 4.5 mm but relatively lower survival rate was 75% in 5.0 mm-over (P < 0.05). The survival rates of implants were 89.51%, 98.28%, 98.34% and 99.27% in the group with isolated sinus graft, with isolated GBR, with sinus graft and GBR simultaneously and without bone graft, especially (P < 0.05). Conclusion: This study establishes a relationship between survival rate of implant and position, diameter of implant system and bone graft technique. In conclusion, there were low survival rates in maxillary posterior site, in dental implants with wide diameter of 5 mm-over, and in the group with isolated sinus graft.

Long-Term Survival Benefit of the Bronchial Arterial Embolization for Patients Presenting with Non-Traumatic Hemoptysis in a District Emergency Center (권역 응급의료센터에 내원한 비외상성 객혈 환자에서 기관지 동맥 색전술의 장기 생존 효과)

  • Chon, Song Bin;Jung, Sung Koo;Kwak, Young Ho;Suh, Gil Joon;You, Eun Young;Shin, Sang Do
    • Tuberculosis and Respiratory Diseases
    • /
    • 제57권2호
    • /
    • pp.148-159
    • /
    • 2004
  • Background : This study was conducted to evaluate the survival benefit of the bronchial arterial embolization (BAE) for patients presenting with non-traumatic hemoptysis. Methods : The clinical data were retrospectively collected from the medical records and the Order Communicating Systems (OCS). The information dealing with death was collected from national death certificates. After enrolled patients were divided with two group such as BAE group (patients who were managed with BAE) and non-BAE group (patients who were managed with conservative modality), the survival benefit of BAE was estimated during the observational period of 24 months through using the Kaplan-Meier survival graph and the Cox-proportional hazard regression analysis. Results : The number of total cases was 272. Of these, BAE group involved 63 and non-BAE group involved 209. 69 cases had the malignant pulmonary lesions, 149 cases had non-malignant chronic lung lesion such as the mycobacteria infection, fungus ball, or bronchiectasis (BE), and 54 cases had the other pathologic conditions. For each sub-groups such as 'malignant lung lesion' group, 'non-malignant chronic lung lesion' group as well as about all cases, the adjusted hazard ratios (HRs) of BAE for death was not significantly different compared to the conservative management. But the adjusted HRs as to underlying causes such as 'malignant lung lesion' group and 'the other conditions' group increased significantly compared to 'non-malignant chronic lung lesion' group. Conclusion : There was no significant survival benefit by BAE procedure on survival in patients presenting with non-traumatic hemoptysis.