• 제목/요약/키워드: E-recruitment

검색결과 113건 처리시간 0.035초

천해어장에서 인위적 환경훼손에 의한 어업생산 감소량 추정방법 (A Quantitative Method for Estimating Damages in Fishery Production due to Artificial Environmental Deterioration in the Tidal Flat Fishing Grounds)

  • 박주석;강용주;장창익
    • 한국수산과학회지
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    • 제36권4호
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    • pp.402-408
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    • 2003
  • A quantitative method was suggested for estimating damages in fishery production due to the diffusion and deposition of suspended silt and clay by various construction processes in tidal flat fishing grounds. Marine populations are maintained through the process of spawning, growth, recruitment, natural death and death by fishing each year. All of the year classes of the population in a fishery ground could be affected when damages occur by human activities such as land filling or reclamation. The propose of this study is to calculate damages in terms of fishery production using a quantitative population dynamic method. If the maximum age in the population is $X_\lambda,$ the starting year of damage is $t_s,$ and the ending year of damage is $t_e,$ the number of year classes damaged is $t_{s-n\lambda}-t_e,$ Many year classes present in the year $t_s,$ and so if damages occur, they Influence all the year classes which are present in the population. Damaged year classes in year $t_e$ would still be in the population until the year $t_{e+n\lambda}$, where $n_{\lambda}$ is the oldest age class. If the expected yield of a year class is constant, the total yield from year classes in the fishing ground during the construction periods can be calculated as follows: $Y_\Phi=[(t_e-t_s+1)+n_c]{\cdot}Y_E+\sum\limits^{n_\lambda-n_c}_{l=1}\;\sum\limits^{n_\lambda-n_c}_{l=i}\;Y_{n_c+i}$ This method was applied for damage estimation in the production of Ruditapes philippinarum in a tidal flat fishing ground.

천식 모델 생쥐에서 필발이 CD25+T 세포수, IgE, Histamine 생성량과 in vitro에서 Th1/Th2 Cytokine Balance에 미치는 영향 (Effects of Piperis Longi Fructus on Regulatory T Cells Number, IgE, Histamine Production in Asthma Model Mice and Th1/Th2 Cytokine Balance in vitro)

  • 이영철;김승형
    • 대한본초학회지
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    • 제24권1호
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    • pp.79-88
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    • 2009
  • Objectives : It has been recently shown that Piperis Longi Fructus (PLF) is involved in the reduction of eosinophil recruitment and production of Th2 cytokines in vivo. However, the main therapeutic mechanisms of PLF remains a matter of considerable debate. To investigate the therapeutic mechanisms of PLF, we examined the influence of PLF on regulatory T cells number, IgE, histamine production in vivo and Th1/Th2 cytokine balance in vitro. Methods : All mice were immunized on two different days (21 days and 7 days before inhalational exposure) by i.p. injections of 0.2 $m\ell$ alum-precipitated Ag containing 100 ${\mu}g$ of OVA bound to 4 mg of aluminum hydroxide in PBS. Seven days after the second sensitization, mice were exposed to aerosolized ovalbumin for 30 min/day on 3 days/week for 12 weeks(at a flow rate of 250 L/min, 2.5% ovalbumin in normal saline) and PLF (150 mg/kg) were orally administered 3 times a week for 8 weeks. Splenocytes from C57BL/6 mice at 8 weeks of age were stimulated with anti-CD3 (1 mg/ml) plus anti-CD28 (1 mg/ml) antibody for 48hrs. IL-4 and IFN-$\gamma$ in the culture supernatants were measured by ELISA Results : The suppressive effects of PLF on asthma model were demonstrated by the increase the number of regulatory T cells and by reducing IgE, histamine production in vivo and modulation of Th1/Th2 cytokine balance. Conclusions : These results indicate that PLF has a deep inhibitory effects on asthma model mice by increase the number of regulatory T cells, and by reducing IgE, histamine production.

박테리아 주화성 검사용 마이크로 플루이딕 칩 (Microfluidic chip for the analysis of bacterial chemotaxis)

  • 이상호;정헌호;김기영;이창수
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 2009년도 제40회 하계학술대회
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    • pp.1521_1522
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    • 2009
  • Chemotaxis is the directed movement of cells in gradients of signaling molecules, an essential biological process that underlies morhpogenesis during development, and the recruitment of immune cells to sites of infection. Especially, bacterial chemotaxis has utilized as an important prelude to study metabolism, prey-predator relationship, symbiosis, other ecological interactions in microbial communities. Recently, novel analytical formats integrated with microfluidics were introduced to investigate the chemotaxis of the cells with the precise control of chemical gradient and small volume of cells. In this study, we present a method to detect bacterial chemotaxis by direct fluidic contacting. The developed fluidic-handling method is driven by capillary force, hydrophobic barrier and a cohesion force between fluids. We have investigated the chemotactic response of E Coli. and Pseudomonas aeruginosa to three kinds of chemoeffectors such as HEPES buffer, peptone and chloroform.

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선천면역 및 적응면역에서 비만세포의 기능 (The Role of Mast Cells in Innate and Adaptive Immunity.)

  • 김영희
    • 생명과학회지
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    • 제18권6호
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    • pp.891-896
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    • 2008
  • The function of mast cells as effector cells in allergy has been extensively studied. Mast cells activated through high affinity IgE-receptor ($Fc{\varepsilon}RI$) release diverse mediators, and lead to smooth muscle constriction, vasodilation, increase of vascular permeability, leukocyte recruitment and activation, mucus secretion, and tissue proliferation and remodeling. However, various other immunological and non-immunological signals can lead to the activation of mast cells. In resent years, mast cells have been identified to be involved in a complex range of immune functions. Mast cells can be important as key players in the regulation of innate as well as adapted immune responses, and may influence the development of allergy, autoimmune disorder and peripheral tolerance. This review summarizes the recent advances in the understanding of effector functions of mast cells in immune responses.

Correlation between water temperature and catch at a set net in Yeosu Bay, Korea

  • Choo, Hyosang
    • Fisheries and Aquatic Sciences
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    • 제24권1호
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    • pp.41-52
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    • 2021
  • Data for fish species composition and the catch of fish species were obtained from the daily trading records for the period between April and December 2016 to 2018 at the set net fishing grounds in Yeosu Bay, Korea. The annual mean total catch was 195.8 tons, and the dominant species was the Spanish mackerel (Scomberomorus niphonius), which accounts for about 55 percent of the total catch. The catch increased in spring and autumn. Increase in spring is caused by not Spanish mackerel but other fish while the increase in autumn by Spanish mackerel. The distinct increase of the catch in summer, 2017 was due to the new recruitment of small-sized Spanish mackerel, which was probably to be from the fish population hatched in spring in the East China Sea. Our results showed a strong correlation between water temperature and catch fluctuation. The catch increases with the increase in water temperatures, and the periodic pattern of the water temperature and catch fluctuation is more consistent in the offshore waters, in which warm current flows, than in the coast waters.

Predicting the Saudi Student Perception of Benefits of Online Classes during the Covid-19 Pandemic using Artificial Neural Network Modelling

  • Beyari, Hasan
    • International Journal of Computer Science & Network Security
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    • 제22권2호
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    • pp.145-152
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    • 2022
  • One of the impacts of Covid-19 on education systems has been the shift to online education. This shift has changed the way education is consumed and perceived by students. However, the exact nature of student perception about online education is not known. The aim of this study was to understand the perceptions of Saudi higher education students (e.g., post-school students) about online education during the Covid-19 pandemic. Various aspects of online education including benefits, features and cybersecurity were explored. The data collected were analysed using statistical techniques, especially artificial neural networks, to address the research aims. The key findings were that benefits of online education was perceived by students with positive experience or when ensured of safe use of online platforms without the fear cyber security breaches for which recruitment of a cyber security officer was an important predictor. The issue of whether perception of online education as a necessity only for Covid situation or a lasting option beyond the pandemic is a topic for future research.

Metabolic Challenges in Anticancer CD8 T Cell Functions

  • Andrea M. Amitrano;Minsoo Kim
    • IMMUNE NETWORK
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    • 제23권1호
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    • pp.9.1-9.15
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    • 2023
  • Cancer immunotherapies continue to face numerous obstacles in the successful treatment of solid malignancies. While immunotherapy has emerged as an extremely effective treatment option for hematologic malignancies, it is largely ineffective against solid tumors due in part to metabolic challenges present in the tumor microenvironment (TME). Tumor-infiltrating CD8+ T cells face fierce competition with cancer cells for limited nutrients. The strong metabolic suppression in the TME often leads to impaired T-cell recruitment to the tumor site and hyporesponsive effector functions via T-cell exhaustion. Growing evidence suggests that mitochondria play a key role in CD8+ T-cell activation, migration, effector functions, and persistence in tumors. Therefore, targeting the mitochondrial metabolism of adoptively transferred T cells has the potential to greatly improve the effectiveness of cancer immunotherapies in treating solid malignancies.

HIF-1α-Dependent Induction of Carboxypeptidase A4 and Carboxypeptidase E in Hypoxic Human Adipose-Derived Stem Cells

  • Moon, Yunwon;Moon, Ramhee;Roh, Hyunsoo;Chang, Soojeong;Lee, Seongyeol;Park, Hyunsung
    • Molecules and Cells
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    • 제43권11호
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    • pp.945-952
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    • 2020
  • Hypoxia induces the expression of several genes through the activation of a master transcription factor, hypoxia-inducible factor (HIF)-1α. This study shows that hypoxia strongly induced the expression of two carboxypeptidases (CP), CPA4 and CPE, in an HIF-1α-dependent manner. The hypoxic induction of CPA4 and CPE gene was accompanied by the recruitment of HIF-1α and upregulation in the active histone modification, H3K4me3, at their promoter regions. The hypoxic responsiveness of CPA4 and CPE genes was observed in human adipocytes, human adipose-derived stem cells, and human primary fibroblasts but not mouse primary adipocyte progenitor cells. CPA4 and CPE have been identified as secreted exopeptidases that degrade and process other secreted proteins and matrix proteins. This finding suggests that hypoxia changes the microenvironment of the obese hypoxic adipose tissue by inducing the expression of not only adipokines but also peptidases such as CPA4 and CPE.

2012년, 2014년과 2016년의 어린이급식관리지원센터에 대한 빅데이터와 오피니언 마이닝을 통한 비교 (Comparison of the Center for Children's Foodservice Management in 2012, 2014, and 2016 Using Big Data and Opinion Mining)

  • 정은진;장은재
    • 대한영양사협회학술지
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    • 제23권2호
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    • pp.192-201
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    • 2017
  • This study compared the Center for Children's Foodservice Management in 2012, 2014, and 2016 using big data and opinion mining. The data on the Center for Children's Foodservice Management were collected from the portal site, Naver, from January 1 to December 31 in 2012, 2014, & 2016 and analyzed by keyword frequency analysis, influx route analysis of data, polarity analysis via opinion mining, and positive and negative keyword analysis by polarity analysis. The results showed that nursery had the highest rank every year and education supported by Center for Children's Foodservice Management has increased significantly. The influx of data has increased through the influx route analysis of data. Blog and $caf\acute{e}e$, which have a considerable amount of information by the mother should be helpful for use as public relations and participation recruitment paths. By polarity analysis using opinion mining, the positive image of the Center for Children's Foodservice Management was increased. Therefore, the Center for Children's Foodservice Management was well-suited to the purpose and the interests of the people has been increasing steadily. In the near future, the Center for Children's Foodservice Management is expected have good recognition if various programs to participate with family are developed and advertised.

Intraovarian vascular enhancement via stromal injection of platelet-derived growth factors: Exploring subsequent oocyte chromosomal status and in vitro fertilization outcomes

  • Wood, Samuel H.;Sills, E. Scott
    • Clinical and Experimental Reproductive Medicine
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    • 제47권2호
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    • pp.94-100
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    • 2020
  • The inverse correlation between maternal age and pregnancy rate represents a major challenge for reproductive endocrinology. The high embryo ploidy error rate in failed in vitro fertilization (IVF) cycles reflects genetic misfires accumulated by older oocytes over time. Despite the application of different follicular recruitment protocols during IVF, gonadotropin modifications are generally futile in addressing such damage. Even when additional oocytes are retrieved, quality is frequently poor. Older oocytes with serious cytoplasmic and/or chromosomal errors are often harvested from poorly perfused follicles, and ovarian vascularity and follicular oxygenation impact embryonic chromosomal competency. Because stimulation regimens exert their effects briefly and immediately before ovulation, gonadotropins alone are an ineffective antidote to long-term hypoxic pathology. In contrast, the tissue repair properties (and particularly the angiogenic effects) of platelet-rich plasma (PRP) are well known, with applications in other clinical contexts. Injection of conventional PRP and/or its components (e.g., isolated platelet-derived growth factors as a cell-free substrate) into ovarian tissue prior to IVF has been reported to improve reproductive outcomes. Any derivative neovascularity may modulate oocyte competence by increasing cellular oxygenation and/or lowering concentrations of intraovarian reactive oxygen species. We propose a mechanism to support intrastromal angiogenesis, improved follicular perfusion, and, crucially, embryo ploidy rescue. This last effect may be explained by mRNA upregulation coordinated by PRP-associated molecular signaling, as in other tissue systems. Additionally, we outline an intraovarian injection technique for platelet-derived growth factors and present this method to help minimize reliance on donor oocytes and conventional hormone replacement therapy.