• Title/Summary/Keyword: Survival Period

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Survival of Bifidobacterium breve in Acidic Solutions and Yogurt, Following Immobilization in Calcium Alginate Beads

  • Lee, Ki-Yong;Kim, Ji-Youn;Yu, Won-Kyu;Lee, Yoon-Jong;Yoon, Sung-Sik;Heo, Tae-Ryeon
    • Journal of Microbiology and Biotechnology
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    • v.11 no.3
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    • pp.412-417
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    • 2001
  • Sodium alginate was used to immobilize Bifidobacterium breve ATCC 15700 cells. The ability of the Ca-alginate beads to protect the B. breve ATCC 15700 was evaluated under different conditions including alginate concentration, bead size, pH, hydrogen peroxide, and storage period. The survival of the B. Breve ATCC 15700 was estimated in pasteurized yogurt, containing either the immobilized or free cells, throughout the storage period. The survival cells in bead after exposure to acidic solution (pH 3.0) increased with increase of both the alginate gel concentration and bead size. Also, immobilized cells in alginate bead were more resistant than the free cells to hydrogen peroxide, storage period, and the environment inside yogur. When retreated beads with skim milk and nonretreated beads were tested in acidified pH 3.0 TPY media including acetic and lactic acid, the number of viable cells in the retreated bead was approximately 10-fold higher than that of nonretreated beads. This suggests that the skim milk operated as a material decreasing the diffusion of acid and hydrogen perosicde into alginate gels. From this research, it was found that yogurt itself supported immobilized cells with an improved protection from the extreme acidity in yogurt.

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An Empirical Study on Survival Characteristics of Young Start-up Entrepreneurs(20~30s) (청년창업기업(20~30대)의 생존특성에 관한 실증연구)

  • Nam, Gi Joung;Lee, Dong Myung
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.13 no.5
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    • pp.63-72
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    • 2018
  • The purpose of this study was to analyze the survival rate and survival characteristics of young start-up entrepreneurs supported with public financing, by using non-parametric statistic of Kaplanr-Meier Analysis on non-financial data. Average survival periods of different survival characteristics have been estimated by dividing the age groups into 20s and 30s. After then, the main variables affecting the survival period have been analyzed. 3,825 firms guaranteed by Credit Guarantee Institutions in Korea were used as database for the analysis. 3,242 firms have survived while 583 firms have gone insolvent. The study period was from January 1, 2011 to December 31, 2017. Age-based breakdown of the business founders show that 3 variables in the 20s and 5 variables in the 30s are derived as the significant variables, resulting in the significant differences of each age group. In other words, the start-up support agencies and financial institutions need to develop a credit evaluation system that distinguishes the criteria of age range and find information that reflect the characteristics of entrepreneurs in their 20s as well as developing tailor-made financial products. Also, step-by-step support measures are required for the start-ups of high survival times and make them grow into promising SMEs. Meanwhile, non-financial support plans shall be invigorated along with the financial ones to help the start-ups of low survival times. This study is meaningful in that the survival analysis has been conducted by using the non-financial data of young start-up entrepreneurs. It is expected that the results of this analysis contribute to the enhancement of survival rate of start-ups by providing start-up support agencies and start-up business owners with the unique information of the survival characteristics.

Effects of Rearing Temperature on Larval Survival and Growth and on Reproductive Traits of Palaemon serrifer (Decapoda: Caridea: Palaemonidae)

  • Kim, Sung-Han
    • Fisheries and Aquatic Sciences
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    • v.13 no.4
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    • pp.308-314
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    • 2010
  • Larvae of Palaemon serrifer were reared in the laboratory under three different temperature regimes ($15^{\circ}C$, $20^{\circ}C$, $25^{\circ}C$) to study the effects of rearing temperature on larval survival and growth, as well as other traits such as embryo volume, number of embryos (fecundity), incubation period, development. Mode and development period. Growth pattern was analyzed by measuring the molt increment and intermolt period. The intermolt period consistently increased with size and instar number and was shortest at $25^{\circ}C$. However, molt increments generally decreased with instar number. Number of embryos varied from 552 to 1355. The relationship between the number of embryos and carapace length was expressed by the equation (fecundity) y=2.7744x+0.208 ($R^2$=0.7961). Egg volume was a primary factor affecting other life-history traits. Egg volume was $0.078\;m^3$, which is relatively small thus embryos exhibited a relatively short incubation period and a comparatively short development period, and the nutritional mode was planktotrophic. Brood production was followed by a fast parturitional pattern. Most ovigerous females had mature ovaries when the parturial molt occurred soon after eclosion.

Effects of Pretense Inhibitors and Antioxidants on In Vitro Survival of Porcine Primordial Germ Cells

  • Lee, Chang-Kyu;Jorge A. Piedrahita
    • Proceedings of the Korean Society of Developmental Biology Conference
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    • 2001.10a
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    • pp.47.1-47
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    • 2001
  • One of the problems associated with in vitro culture of primordial gern cells (PGCs) is the large loss of cells during the initial period of culture. This study characterized the initial loss and determined the effectiveness of two classes of apoptosis inhibitors, protease inhibitors and antioxidants, on the ability of the porcine PGCs to survive in culture. Results from electron microscopic analysis and in situ DNA fragmentation assay indicated that porcine PGCs rapidly undergo apoptosis when placed in culture. Additionally, \ulcorner2-macroglobulin, a protease inhibitor and cytokine carrier, and N-acetylcysteine, an antioxidant, increased the survival of PGCs in vitro. While other protease inhibitors tested did not affect survival of PGCs, all antioxidants tested improved survival of PGCs (p<0.05). Further results indicated that the beneficial effect of the antioxidants was critical only during the initial period of culture. Finally, it was determined that in short-term culture, in the absence of feeder layer, antioxidants could partially replace the effect(s) of growth factors and reduce apoptosis. Collectively, these results indicate that the addition of \ulcorner2-macroglobulin and antioxidatns can increase the number of PGCs in vitro by suppressing apoptosis.

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Effects of Protease Inhibitors and Antioxidants on In Vitro Survival of Porcine Primordial Germ Cells

  • Lee, Chang-Kyu;Jorge A. Piedrahita
    • Proceedings of the KSAR Conference
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    • 2001.10a
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    • pp.47-47
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    • 2001
  • One of the problems associated with in vitro culture of primordial germ cells (PGCs) is the large loss of cells during the initial period of culture. This study characterized the initial loss and determined the effectiveness of two classes of apoptosis inhibitors, protease inhibitors and antioxidants, on the ability of porcine PGCs to survive in culture. Results from electron microscopic analysis and in situ DNA fragmentation assay indicated that porcine PGCs rapidly undergo apoptosis when placed in culture. Additionally,? 2-macroglobulin, a protease inhibitor and cytokine carrier, and N-acetylcysteine, an antioxidant, increased the survival of PGCs in vitro. While other protease inhibitors tested did not affect survival of PGCs, all antioxidants tested improved survival of PGCs (p〈0.05). Further results indicated that the beneficial effect of the antioxidants was critical only during the initial period of culture. Finally, it was determined that in short-term culture, in the absence of feeder layers, antioxidants could partially replace the effect(s) of growth factors and reduce apoptosis. Collectively, these results indicate that the addition of ?2-macroglobulin and antioxidants can increase the number of PGCs in vitro by suppressing apoptosis.

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Survival rate of stainless steel crown restorations according to depth of caries in primary molars (유구치에서 우식의 깊이에 따른 기성 금속관 수복물 생존율 연구)

  • Yoo, Hyunkyoung;Ra, Jiyoung;Lee, Jewoo
    • The Journal of the Korean dental association
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    • v.57 no.10
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    • pp.569-578
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    • 2019
  • The purpose of this retrospective study was to compare outcome of preformed stainless steel crown restorations according to depth of caries in primary molars. The study subjects consisted primary molars having dentin caries extending at least one-fourth of dentin without signs and symptoms of irreversible pulpitis. A total 295 primary molars received preformed stainless steel crown restorations without any base materials were included in this study. Survival rates were compared using a Kaplan-Meier analysis test. There was no significant difference between depth of caries and survival period in primary molars. And also there was no significant difference with or without pulp therapy. The results of this study suggest that neither the amount of caries nor pulp therapy affect the survival period of primary molars significantly. Proper restoration is more important to achieve sealing for stopping caries progression.

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An 8-year survival rate of immediate implants: retrospective study (발치후 즉시 임플란트의 8년 누적 생존율에 대한 후향적 연구)

  • Ko, Seung-Hee;Chang, Yun-Young;Um, Yoo-Jung;Jung, Ui-Won;Kim, Chang-Sung;Cho, Kyoo-Sung;Choi, Seong-Ho
    • The Journal of the Korean dental association
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    • v.47 no.11
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    • pp.758-768
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    • 2009
  • Purpose : Schulte introduced immediate implant cases in 1970s, since then many patients have been treated by immediate implants. The aim of this study was to evaluate the cumulative survival rate of immediate implant and to analyze various factors associated with survival of immediate implant in a 8-year period retrospectively. Materials and methods : From May, 2000 to October, 2007, 77 implants were placed in 63 patients immediately after tooth extraction at Department of Periodontology, Yonsei University Hospital. The implant survival rate was analyzed using a life-table analysis. After delivery of prosthesis, along 1 year of observation period, all implants were evaluated clinically and radiographically. Results : Among 77 implants, 59 were placed in maxilla and 18 in mandible. The most common site of the implantation was Mx anterior (65%). The overall survival rate was 94.8% over a mean follow-up period of $44.2{\pm}21$ months and the 8-year cumulative survival rate was 94.6%. Failure occurred in 4 implants, all of which were due to early failures. None of the following factors were significantly associated with the survival of immediate implants: advanced surgical technique including bone graft and guided bone regeneration, the types of implants, causes of tooth loss, and types of prosthesis. Conclusion : On the basis of 8-year life time analysis, immediate implant placement can be considered a safe and predictable treatment mordality.

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A Retrospective Study of Survival Rate in single Brnemark TiUniteTM Implant (단일 치아 결손시 TiUniteTM 표면 처리한 임플란트의 생존율에 대한 후향적 연구)

  • Kim, Hye-Jin;Yang, Seung-Min;Kye, Seung-Beom;Shin, Seung-Yun
    • Journal of Dental Rehabilitation and Applied Science
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    • v.25 no.3
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    • pp.267-277
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    • 2009
  • Recently implant supported single crown is the popular treatment option to replace a single missing tooth. The purpose of this retrospective study was to analyze and evaluate the survival of implants with the $TiUnite^{TM}$ surface for single tooth replacement. From September 2002 to December 2006, 269 TiUniteTM surfaced implants were used in single tooth replacements at the Institute of Oral Health Science, Samsung Medical Center. Twenty one cases were excluded because of neighbor implants, missing records & short follow up period. Among 248 implants, the 129 implants (52.0%) were inserted in the maxilla and 119 (48.0%) in the mandible. One hundred implants placement (40.3%) were combined with guided bone regeneration, and 36 implants placement (14.5%) were combined with sinus bone augmentation. Mean observation period was $26.0{\pm}11.8$ months after implant placement. Twelve implants were recorded as failures, rendering a single implant survival rate of 95.2% over the observation period. Among failed 12 implants, 10 implants placed in the maxilla. The survival rate in the maxilla was 92.2% and in the mandible was 98.3%. The use of $TiUnite^{TM}$ surfaced single implant placement showed high survival rate for short time period.

A prediction of overall survival status by deep belief network using Python® package in breast cancer: a nationwide study from the Korean Breast Cancer Society

  • Ryu, Dong-Won
    • Korean Journal of Artificial Intelligence
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    • v.6 no.2
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    • pp.11-15
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    • 2018
  • Breast cancer is one of the leading causes of cancer related death among women. So prediction of overall survival status is important into decided in adjuvant treatment. Deep belief network is a kind of artificial intelligence (AI). We intended to construct prediction model by deep belief network using associated clinicopathologic factors. 103881 cases were found in the Korean Breast Cancer Registry. After preprocessing of data, a total of 15733 cases were enrolled in this study. The median follow-up period was 82.4 months. In univariate analysis for overall survival (OS), the patients with advanced AJCC stage showed relatively high HR (HR=1.216 95% CI: 0.011-289.331, p=0.001). Based on results of univariate and multivariate analysis, input variables for learning model included 17 variables associated with overall survival rate. output was presented in one of two states: event or cencored. Individual sensitivity of training set and test set for predicting overall survival status were 89.6% and 91.2% respectively. And specificity of that were 49.4% and 48.9% respectively. So the accuracy of our study for predicting overall survival status was 82.78%. Prediction model based on Deep belief network appears to be effective in predicting overall survival status and, in particular, is expected to be applicable to decide on adjuvant treatment after surgical treatment.

Roles of Ethnicity in Survival of Hepatocellular Carcinoma Patients in Malaysia

  • Azmawati, M.N.;Krisnan, R.
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.12
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    • pp.6023-6026
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    • 2012
  • The incidence of hepatocellular carcinoma (HCC) in Malaysia for the year 2001 was 2.8 per 100,000 people. The mortality rate is increasing. A retrospective cohort study measuring the survival of HCC patients who received treatment in Selayang Hospital was conducted from 1 January 2003 to 31 December 2006. The main objectives of the study were to measure the survival of the patients and to understand the influencing factors, especially ethnicity. The subjects were newly diagnosed cases of HCC by CT scan and histopathological assessment who underwent futher investigations and treatments in Hospital Selayang (inception cohort). The survival time was measured from the date of diagnosis until the subjects died, or failed to follow-up at the end of the study period (31 December 2007). A total of 299 patients were selected with 95 patients dying, the majority among Chinese (39.1%). Subgroup analysis according to ethnicity proved significantly that Chinese patients who had smaller tumor, less number of nodules, low AFP level, Child Pugh Class A and received surgical treatment had a better median survival rate compared to other ethnic groups. Malay (cHR: 1.3, 95%CI; 0.89-1.85) and Indian (cHR: 1.3, 95%CI; 0.74-2.26) patients had a poor survival compared to Chinese patients, but not in the final model. Therefore ethnicity may play a role in survival of HCC patients, but not as a main hazard prognostic factor.