• Title/Summary/Keyword: frequency of occurrence

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Effect of kinds and concentrations of osmoticum on somatic embryo induction and germination from suspended embryogenic cell in Larix kaempferi (낙엽송(Larix kaempferi) 현탁배양된 배발생세포로부터 체세포배 유도 및 발아를 위한 삼투압제 종류 및 농도 효과)

  • Kim, Yong-Wook
    • Journal of Plant Biotechnology
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    • v.40 no.3
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    • pp.141-146
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    • 2013
  • This study was conducted to examine suspended embryogenic cells growth with days of culture, effects of various kinds/concentrations of osmoticum for induction of somatic embryos (SEs), following somatic embryos germination or plantlet regeneration. The proliferation pattern of embryogenic cells in suspension culture is characterized by settled cells volume (SCV) increased with the duration of culture with marked the maxium of SCV (10.1 ml) in 18 days of culture, however the SCV of cells gradually decreased after that. In comparison of kinds/concentrations of osmoticum on somatic embryo induction, the highest induction number (352.3/g FW) of the SE was showed in 0.2 M sucrose, in addition, we also observed some effects with treatments of 0.2 M maltose (203.7) and 0.3 M maltose (193.7), respectively. However, no somatic embryos produced in treatments of 7.5% PEG plus 0.15 M sucrose or maltose. In comparison of germination efficiency of SEs which occurred from the treatments of various kinds/ concentrations of osmoticum, the highest induction frequency of cotyledon (25.2%) was obtained from SEs that produced 0.3 M maltose, however, the best occurrence rates of hypocotyl (39%), radicle (30.3%) and plantlet regeneration (3.5%) were observed from the 0.2 M sucrose treatment, respectively.

The Study for Enhancing Resilience to Debris Flow at the Vulnerable Areas (토석류 재해발생 시 레질리언스 강화를 위한 연구)

  • Kim, Sungduk;Lee, Hojin;Chang, Hyungjoon;Dho, Hyonseung
    • Journal of the Korean GEO-environmental Society
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    • v.22 no.8
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    • pp.5-12
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    • 2021
  • Climate change caused by global warming increases the frequency of occurrence of super typhoons and causes various types of sediment disasters such as debris flows in the mountainous area. This study is to evaluate the behavior of debris flow according to the multiplier value of the precipitation characteristics and the quantity of debris flow according to the typhoon category. For the analysis of the debris flow, the finite difference method for time elapse was applied. The larger the typhoon category, the higher the peak value of the flow discharge of debris flow and the faster the arrival time. When the precipitation characteristic multiplier is large, the fluctuation amplitude is high and the bandwidth is wide. When the slope angle was steeper, water discharge increased by 2~2.5 times or more, and the fluctuation of the flow discharge of debris flow increased. All of the velocities of debris flow were included to the class of "Very rapid", and the distribution of the erosion or sedimentation velocity of debris flows showed that the magnitude of erosion increased from the beginning, large-scale erosion occurred, and flowed downstream. The results of this study will provide information for predicting debris flow disasters, structural countermeasures and establishing countermeasures for reinforcing resilience in vulnerable areas.

Analysis of Department of Home Economics Education Curriculum of College of Education through Keyword Network Analysis (키워드 네트워크 분석을 통한 사범대학 가정교육과 교육과정 분석)

  • Park, Jisoon;Ju, Sueun
    • Journal of Korean Home Economics Education Association
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    • v.35 no.1
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    • pp.105-124
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    • 2023
  • The purpose of this study was to identify the characteristics of the contents included in the curriculum and 382 syllabi of the department of home economics education of College of Education in Korea and analyze the correlation by detailed area through the keyword network method. In order to analyze the home economics education curriculum and 382 syllabuses of a total of 11 universities, the frequency of keyword occurrence was analyzed using the KrKwic program, also the degree of connection between keywords and various centrality scales were calculated and visualized. The results of this study were as follows. First, as a result of analyzing the entire syllabi, keywords representing various fields such as family, secondary school, clothing, food, consumer, and design appeared evenly, and keywords related to teaching methods such as 'method', 'practice', 'change', and 'principle' were appeared. Those keywords showed high degree of connection and centrality. Second, in the detailed sectoral analysis, core keywords for each area appeared, and each subject were found to reflect the core keywords of the academic base. This study contributes to the conversion of curriculum of the department of home economics education to future-oriented and convergent curriculum.

Design of PWM-Based Photo Irradiation System for Acne Treatment (여드름 치료를 위한 PWM 기반 광 조사 시스템 설계)

  • Kim, Chang-Su;Lim, Hyun-Soo
    • Journal of the Korean Society of Radiology
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    • v.6 no.3
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    • pp.207-215
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    • 2012
  • As one of photo dynamic therapies, the existing LED photo irradiation method with 635 nm continuous wave has most frequently been used for acne treatment, it suffered from a low energy efficiency and generation of a large amount of heat in tissues requiring improvement measures. In this thesis, a LED photo irradiation system for acne treatment has been designed using PWM(Pulse Width Modulation) mode to enhance the energy efficiency and prevent thermal destruction in tissues. System configuration consisting largely of timer module, PWM module, and photo transfer device has been designed with the use of 1 W LED at a wavelength of 660 nm for the photo transfer device to increase skin penetration depth for treatment of acne. Frequency and wave form generated by using PWM control was verified along with confirmation of output energy of 660 nm LED and surface temperatures of tissues, followed by evaluation of stable energy outputs and stability of tissues. The results indicated that whereas power loss was high and thermal destruction in tissues was exhibited when C.W mode was used to obtain the optical energy of 1 W LED at a wavelength of 660 nm for acne treatment, realization of PWM mode allowed lowering of power consumption for LED through pulse width modulation, and no occurrence of thermal destruction in tissues, suggesting that PWM mode is safer and more effective for treatment of acne than C.W mode.

Comparative assessment of age, growth and food habit of the black-chinned tilapia, Sarotherodon melanotheron (Rüppell, 1852), from a closed and open lagoon, Ghana

  • Zuh, Cephas Kwesi;Abobi, Seth Mensah;Campion, Benjamin Betey
    • Fisheries and Aquatic Sciences
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    • v.22 no.12
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    • pp.31.1-31.12
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    • 2019
  • Background: The black-chinned tilapia, Sarotherodon melanotheron, is the most abundant fish species in the Nakwa (an open lagoon) and Brenu (a closed lagoon) in the Central Region of Ghana. Aspects of the life history characteristics and the ecology of the fish populations in both lagoons were studied to assess the bio-ecological status of this important resource. Methods: Fish samples were obtained from fishermen that fish on the Nakwa and Brenu lagoons using cast, drag and gill nets. The age of the fish was assessed from otoliths analysis and its growth modelled following the von Bertalanffy growth function. Morphometric characteristics of the fish populations were analysed using power regression and ANOVA for parameters comparisons, and Student's t test to determine whether species grew isometrically. The percentage occurrence method was used to analyse the stomach contents of the fish. Results: A total of 382 fish samples from both lagoons were measured, comprising 209 from Nakwa lagoon and 176 from Brenu lagoon. The size and weight of fish samples ranged between 3.9-11.5 cm total length and 1.0-27.3 g for Nakwa Lagoon and 5.6-12.8 cm total length and 3.2-29.8 g for the Brenu Lagoon. The estimated von Bertalanffy growth parameters were L∞ = 12.04 cm and K = 2.76/year for the Nakwa Lagoon samples and L∞ = 13.44 cm and K = 3.27/year for Brenu Lagoon samples. Daily otolith incremental rate ranged from 0.01-0.03 mm per day to 0.01-0.02 mm per day for Nakwa and Brenu lagoons, respectively. Stomach content analysis of the fish samples revealed that the species are planktivorous and the range of food varied between the lagoons. Green algae were the most prevalent food item in the stomachs of the fish samples from Nakwa with the frequency of 69% whilst diatoms (80.5%) were most prevalent phytoplanktonic food item for the fish in Brenu lagoon. Conclusions: The estimates of asymptotic length for the species in both lagoons are close to known values of the species length at first sexual maturity and points to intensive fishing pressure. As a consequence, a comprehensive sample-based survey is required in both lagoons to derive estimates of management reference points. The results of the stomach content analysis are beneficial to the construction of diet matrix for ecosystem models of the two systems.

Prevalence and Quantification of Vibrio parahaemolyticus in Raw Salad Vegetables at Retail Level

  • Tunung, R.;Margaret, S.P.;Jeyaletchumi, P.;Chai, L.C.;Zainazor, T.C. Tuan;Ghazali, F.M.;Nakaguchi, Y.;Nishibuchi, M.;Son, R.
    • Journal of Microbiology and Biotechnology
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    • v.20 no.2
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    • pp.391-396
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    • 2010
  • The purpose of this study was to investigate the biosafety of Vibrio parahaemolyticus in raw salad vegetables at wet markets and supermarkets in Malaysia. A combination of the most probable number-polymerase chain reaction (MPN-PCR) method was applied to detect the presence of V. parahaemolyticus and to enumerate their density in the food samples. The study analyzed 276 samples of common vegetables eaten raw in Malaysia (Wild cosmos=8; Japanese parsley=21; Cabbage=30; Lettuce=16; Indian pennywort=17; Carrot=31; Sweet potato=29; Tomato=38; Cucumber=28; Four-winged bean=26; Long bean=32). The samples were purchased from two supermarkets (A and B) and two wet markets (C and D). The occurrence of V. parahaemolyticus detected was 20.65%, with a higher frequency of V. parahaemolyticus in vegetables obtained from wet markets (Wet market C=27.27%; Wet Market D=32.05%) compared with supermarkets (Supermarket A=1.64%; Supermarket B=16.67%). V. parahaemolyticus was most prevalent in Indian pennywort (41.18%). The density of V. parahaemolyticus in all the samples ranged from <3 up to >2,400 MPN/g, mostly <3 MPN/g concentration. Raw vegetables from wet markets contained higher levels of V. parahaemolyticus compared with supermarkets. Although V. parahaemolyticus was present in raw vegetables, its numbers were low. The results suggest that raw vegetables act as a transmission route for V. parahaemolyticus. This study will be the first biosafety assessment of V. parahaemolyticus in raw vegetables in Malaysia.

Responses and adverse effects of carboplatin-based chemotherapy for pediatric intracranial germ cell tumors

  • Ji, Sun-Tae;Chueh, Hee-Won;Kim, Ju-Youn;Lim, Su-Jin;Cho, Eun-Joo;Lee, Soo-Hyun;Yoo, Keon-Hee;Sung, Ki-Woong;Koo, Hong-Hoe
    • Clinical and Experimental Pediatrics
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    • v.54 no.3
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    • pp.128-132
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    • 2011
  • Purpose: Cisplatin-based chemotherapy has been commonly used for the treatment of intracranial germ cell tumors (IC-GCTs). However, this treatment exhibits some adverse effects such as renal problems and hearing difficulty. Carboplatin-based chemotherapy was administered to pediatric patients with IC-GCTs from August 2004 at the Samsung Medical Center. In this study, we assessed the responses and adverse effects of carboplatin-based chemotherapy in pediatric IC-GCTs patients according to the risk group, and compared the results with those of the previous cisplatin-based chemotherapy. Methods: We examined 35 patients (27 men and 8 women) diagnosed with IC-GCTs between August 2004 and April 2008 and received risk-adapted carboplatin-based chemotherapy at the Samsung Medical Center. Patients were divided into either low-risk (LR) or high-risk (HR) groups and a retrospective analysis was performed using information from the medical records. Results: Although hematological complications were common, hearing difficulties or grade 3 or 4 creatinine level elevation were not observed in patients who underwent carboplatin-based chemotherapy. The frequency of febrile neutropenia did not differ between the risk groups. The overall survival was 100% and event-free survival (EFS) was 95.7%. The EFS rate was 100% in the LR group and 90% in the HR group, respectively. Conclusion: Despite their common occurrence in high-risk patients, no lethal hematological complications were associated with carboplatin-based treatment. The current carboplatin-based chemotherapy protocol is safe and effective for the treatment of pediatric patients with IC-GCTs.

The Optimal Shock Intensity and C-arm Total Running Time in Patients with Inferior Ureter Stones during Electromagnetic of ESWL (전자기식 체외충격파쇄석술시 하부요관 결석 환자에 대해 적합한 충격강도와 C-arm 총 가동시간)

  • Park, Jeong Kyu;Cho, Euy Hyun
    • Journal of the Korean Society of Radiology
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    • v.8 no.7
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    • pp.461-466
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    • 2014
  • The advantages and disadvantages of the various models of crushed ESWL (Extracorporeal Shock Wave Lithotripsy) and their various side effects due to pre-treatment have been reported. We look for the appropriate intensity of the shock wave in the electromagnetic ESWL treatment of patients with lower Inferior Ureter Stones and measure the total running time of C-arm saw. This study is based on the January-June 2014 launch of 65 patients of C university hospital located in Gyeongbuk, who conducted ESWL without pre-treatment. Patients are composed of 48 male and 17 female which were more common in men, while the most common age is 50s. The occurrence of lower urinary tract stones were left and they were more absent than 5mm in size in 39 of the most common. Optimal intensity is one of the suitable intensity of pain, and it is possible to switch the strength of impact to C if one appeals pain. In addition, the C-arm of the total operating time showed $241.73{\pm}30.37$ seconds, which is the size of the lower urinary tract that showed a significant difference (p <0.05). Therefore, ESWL treatment without pre-enforce treatment, the standard for the impact frequency and impact strength depending on the site of ureteral stones is required. The standard for total operating time of C-arm generated for ureteral stones is needed in order to reduce radiation exposure, and the standard for the total operating time for the criteria is needed depending on the site in order to minimize the exposure.

Characteristics of Nitro-nutrients and Phytoplankton Dynamics in the Yeongsan River after Weir Construction (보 건설 이후 영산강 보 구간에서의 질소계열 영양염류 및 식물플랑크톤 동태)

  • Seo, Kyung-Ae;Na, Jeong-Eun;Ryu, Hui-Seong;Kim, Kyunghyun
    • Journal of Korean Society on Water Environment
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    • v.34 no.4
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    • pp.423-430
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    • 2018
  • Insomuch as it is important to manage water quality, from the perspective of water management, it is essential to understand the effect of the weirs on water quality and phytoplankton dynamics in various regions. The purpose of this study is to investigate the characteristics of nitro-nutrients, as well as occurrences and succession patterns of phytoplankton, in the river sections of the two weirs in the Yeongsan River for the five years (from 2012 to 2016) after the weir construction. In respect to this data, the average water temperature measured at the representative point in the section of the Seungchon Weir ($17.1^{\circ}C$) was higher than that of the Juksan Weir ($16.6^{\circ}C$) by comparison. By way of an analysis of this data, it was found that the water quality variables such as, organic matter, nitrogen nutrients and phosphorus nutrients were improved gradually during the period, but the degree of the improvement differs as noted and measured between the weirs. Under the circumstances, it is especially noted that the $NH_3-N$ concentration was higher for the point of the Seungchon Weir (2.204 mg/L) than that of the Juksan Weir (1.157 mg/L). This indicates that effluent as seen from sewage treatment plants and hydrological feature near the densely population area, could be the main cause for the incidence of water pollution in the upstream section of the Seungchon Weir. Additionally, the phytoplankton analysis showed that a relative abundance of diatoms and green algae were 56.9 % and 25.8 % respectively. However, it is noted that the cyanobacteria was measured lower as 10.7 %. Also, in the study sites cell density and occurrence frequency of cyanobacteria were relatively lower than compared to the same measurements noted in other rivers.

A study on the analysis of current status of Seonakdong River algae using hyperspectral imaging (초분광영상을 이용한 서낙동강 조류 발생현황 분석에 관한 연구)

  • Kim, Jongmin;Gwon, Yeonghwa;Park, Yelim;Kim, Dongsu;Kwon, Jae Hyun;Kim, Young Do
    • Journal of Korea Water Resources Association
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    • v.55 no.4
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    • pp.301-308
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    • 2022
  • Algae is an indispensable primary producer in the ecosystem by supplying energy to consumers in the aquatic ecosystem, and is largely divided into green algae, blue-green algae, and diatoms. In the case of blue-green algae, the water temperature rises, which occurs in the summer and overgrows, which is the main cause of the algae bloom. Recently, the change in the occurrence time and frequency of the algae bloom is increasing due to climate change. Existing algae survey methods are performed by collecting water and measuring through sensors, and time, cost and manpower are limited. In order to overcome the limitations of these existing monitoring methods, research has been conducted to perform remote monitoring using spectroscopic devices such as multispectral and hyperspectral using satellite image, UAV, etc. In this study, we tried to confirm the possibility of species classification of remote monitoring through laboratory-scale experiments through algal culture and river water collection. In order to acquire hyperspectral images, a hyperspectral sensor capable of analyzing at 400-1000 nm was used. In order to extract the spectral characteristics of the collected river water for classification of algae species, filtration was performed using a GF/C filter to prepare a sample and images were collected. Radiation correction and base removal of the collected images were performed, and spectral information for each sample was extracted and analyzed through the process of extracting spectral information of algae to identify and compare and analyze the spectral characteristics of algae, and remote sensing based on hyperspectral images in rivers and lakes. We tried to review the applicability of monitoring.