• Title/Summary/Keyword: period of active growth

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Elementary Teachers' Perception, Practice, and Background Factors in Using Students' Everyday Experience in Teaching Science (과학수업에서 학생의 일상경험 도입에 대한 초등교사의 인식과 실행 및 배경요인)

  • Na, Jiyeon;Song, Jinwoong
    • Journal of The Korean Association For Science Education
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    • v.34 no.7
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    • pp.635-645
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    • 2014
  • The purpose of this study is to identify elementary school teachers' perceptions, practices, and background factors related to introducing students' everyday experience in science teaching process. The participants of this study were four elementary school teachers who have different features such as major, teaching period, gender, growth area, and age. The data was collected through semi-constructed and in-depth interviews. The results of the research are as follows: Teachers mostly used students' everyday experience during the introduction phase of science lessons for the purpose of motivation. They hold a positive view of using students' everyday experience during science lessons and thought that science teaching needs to actively use more of students' everyday experience, while in actual practice they disregarded or only passively introduced students' everyday experience. The various background factors found to affect teachers' practice are as follows: positive memory on their science class; educational experience of their own children; their own childhood environment; their learning style; their insufficient knowledge or enthusiasm; perceived educational value of everyday life in science education; teacher's duties; importance of students' achievement; difficulty in guiding experiment; reaction of students on introducing everyday experience; characteristics of science textbook and teacher's guidebook; lack of lesson time; realization of national common basic education; characteristics of their students; demands from parents or students; effect of introducing everyday experience. In addition, we found that the teachers behave not in accordance with what they thought due to external factors related to their profession and that, for a more active use of students' everyday experience in their teaching, teachers need support from textbooks and teachers' guidebooks.

Effect of highly activated calcium on the growth of mushrooms (고활성칼슘의 버섯 생육에 대한 효과)

  • Chang, Hyun-You;Goo, Ja-Joon
    • Journal of Mushroom
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    • v.3 no.1
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    • pp.35-39
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    • 2005
  • Highly Activated Calcium(below HAC) is the oxidized calcium made by dissolving shell materials with high voltage about 15,000V and high temperature ($1,500{\sim}5,000^{\circ}C$). This HAC is a material with a very high degree of purity without toxicant. This HAC decreases chemical reaction so the degree of being active and dissolving living material is outstanding. The effects of HAC on the propagation of mushrooms are following. In the case of the Pleurotus ostreatus, when controlling media moisture by mixing with the HAC, mycelium cultivating days were shortened by 2days. The day required for primordial formation after inoculation(DPI) were one day faster. The number of stem was 15 and individual weight was 248g/850cc, a 6.5% increase. In the case of Pleurotus eryngii, when controlling media moisture by mixing with the highly activated calcium, mycelium cultivating days were shortened by 3days. DPI were l day faster. The day required for colonization after inoculation was shortened by 6days and individual weight was 108.8g/850cc, a 9.7% increase. In the case of Flammulina velutipes, the highly activated calcium was the best for scraping up mycelium. Mycelium incubating days were shortened by 2days. DPI were shortened by 3days. The day required for colonization after inoculation was 1day faster and the period of cultivation was shortened by 3days. Individual weight was 165g/850cc, a 6.7% increase. In the case of Lentinula edodes, when mixing media with the highly cultivated calcium, cultivating days were shortened by 3 days. The days for becoming brown in color were 2 days faster and the days of the first harvest were shortened by 4 days. The weight of mushrooms was 169g/2kg, a 9.7% increase.

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Metabolic Imbalance between Glycolysis and Mitochondrial Respiration Induced by Low Temperature in Rice Plants (벼 냉해의 초기 기작으로서 생체막과 세포질 사이의 대사 불균형)

  • Lee, Keun-Pyo;Boo, Yong-Chool;Jung, Jin
    • Applied Biological Chemistry
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    • v.43 no.4
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    • pp.236-240
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    • 2000
  • Correlations between mitochondrial respiration, glycolysis activity and overall growth activity of rice (Oryza sativa: cv. Dasan) seedlings during low temperature exposure were studied in order to provide insights into the underlying mechanism for the primary phase of chilling injury in plants. Among cellular membranes involved in energy metabolism, only the mitochondrial inner membrane showed not only physical phase transition at ca. $13^{\circ}C$, as monitored by ESR spin label, but also functional phase transition at the same temperature, as assessed by cytochrome c oxidase activity. The main regulatory enzyme of glycolysis, phosphofructokinase, in situ did not suffer phase transition of its activity at least in the $4{\sim}27^{\circ}C$ range. Low temperature caused a significant accumulation of glucose 6-phosphate (G6P) and fructose 6-phosphate (F6P), which disappeared almost completely on rewarming of the seedlings. Temperature profiles of the steady state levels of G6P and F6P revealed the inflection point appearing at around phase transition temperature of the mitochondrial membrane. The results conform to our previous proposition on the mechanism for the early stage events of chilling injury that the accumulation of glycolytic metabolites in cells due to metabolic imbalance at low temperature gives rise to an excess supply of electrons during rewarming period, which, in turn, results in overproduction of active oxygen in mitochondria.

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Restriction of Ca2+ deficiency-like symptoms by co-expressing a Ca2+ transporter and a Ca2+-binding protein in tomato (토마토에서 칼슘수송체와 칼슘결합단백질 공동발현에 의한 칼슘결핍유사증상의 완화)

  • Han, Jeung-Sul;Kang, Ho-Ju;Kim, Chang-Kil
    • Journal of Plant Biotechnology
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    • v.37 no.4
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    • pp.549-555
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    • 2010
  • Here we focused on tip-burn and blossom-end rot (BER) symptoms in the tomato plants expressing the constitutively active form of $Ca^{2+}/H^+$ antiporter (sCAX1) and/or a Ca-binding protein (calreticulin, CRT) genes during their whole growth period. Conclusively we demonstrated that CRT is able to suppress the tip-burn and BER symptoms that were induced by sCAX1. Under poor nutrition condition, tomato plants overexpressing sCAX1 showed severe necrotic collapses in both roots and shoot polar tissues, which are in accordance with $Ca^{2+}$ deficient symptoms frequently observed in an agricultural cultivation of tomato. Reciprocal grafting trials using sCAX1 and wild type plants revealed that the tip-burn symptom by sCAX1 overexpression is not caused by hindrance of $Ca^{2+}$ uptake from soil. We constructed CRT overexpressing transgenic tomatoes, and crossed them with sCAX1 transgenic plants to investigate the effects of CRT on the symptoms of sCAX1 transgenic plants. Co-expression of sCAX1 and CRT significantly suppressed the $Ca^{2+}$ deficient symptoms of sCAX1 transgenic plants. Those results suggest the model that $Ca^{2+}$ homeostasis disturbed by the overexpression of sCAX1 may be suppressed by the co-expression of CRT.

Anaerobic Biological Treatment of Abandoned Metallic Mine Drainages with Limestone and Recycling of Papermill and Livestock Sludge (석회석과 제지·축산슬러지를 재활용한 폐금속광산폐수의 혐기성 처리)

  • Kim, Eun-Ho;Kim, Hyeong-Seok;Sung, Nak-Chang
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.3
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    • pp.463-473
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    • 2000
  • This research was carried out to investigate chemical pretreatment using limestone in treating abandoned metallic mine drainage with anaerobic biological treatment, and to estimate application of papermill and livestock sludge as carbon sources for SRB (Sulfate Reducing Bacterial. Capacity of anaerobic limestone bed was steeply decreased. But if limestone was utilized as pretreatment process in treating them with anaerobic biological treatment. it could look forward to stabilize system because it did initally neutralize them. Effluent SCOD in R-4 was lower than R-l~R-3 in inital HRT 5day but its concentration was high in HRT 1day after passed time. Therefore in point of durability and supply of organic matter. it seemed that R-4 was useful became organic matter in R-4 was not consumed by excessive degradation within short period. In all reactors, pH was suitable for SRB growth in whole HRT, but on the evidence of ORP, SRB was active after HRT 2day. Fixation trend of heavy meta s showed high as $SO_4{^{2-}}$ reduction efficiency increased, and $SO_4{^{2-}}$ reduction and fixation of heavy metals were relatively high in HET 2day.

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A Study on the Time-Sectional Analysis of Apartment Housing related research in Korea (국내 아파트 관련 연구의 연구주제 시계열 분석)

  • Kim, Tae-Sok;Park, Jong-Mo;Park, Eu-Gene;Han, Dong-Suk
    • Journal of the Architectural Institute of Korea Planning & Design
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    • v.34 no.3
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    • pp.45-52
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    • 2018
  • Currently, apartments have become an important research subject for the overall area of politics, economics, and culture as well as urban architectural study. However, there are few analyses of the research trends related to the current interest in the apartment research and prediction of the future changes of an apartment in politics and industry. In this study, the research information related to the apartment has classified, and the changes in the research trends have analyzed. Based on the classified data, the first thesis and dissertation related to the apartment and changes of academic notation have discovered. In addition, future interests and future research directions through Frequency of Appearance, Degree Centrality Analysis, and Betweenness Centrality Analysis of author keywords were predicted. As a result of the analysis, 'Space,' 'Residential Mobility' and 'Apartment Complex' studies were found to be important research topics throughout the entire period. 'Han Gang Apartment,' 'Small Size Apartment,' 'Civic Apartments,' 'Jamsil,' and 'Child' were newly interested topics until 70's era. '(Super) High-rise Apartment,' 'Perception,' 'Jugong Apartment,' 'Housing Environment,' 'Housewife,' 'Apartment Layout,' and 'Busan' were newly interested topics during the 80's and 90's era. 'Apartment Price,' 'Energy,' 'Remodeling,' 'Noise,' 'Resident Satisfaction,' 'Community,' and 'Apartment Lotting-out' were newly interested topics after the year 2000. New concerns for last decade are found to be 'Super High-rise Apartment', 'Remodeling', 'Indoor'(2007), 'Apartment Reconstruction Project', 'Brand', 'AHP', 'Housing Environment'(2008), 'Ventilation'(2009), 'Apartment Lotting-out'(2010), 'Economic Assessment'(2011), 'Cost'(2012), 'Green Building', 'Apartment Sales', 'Law', 'Society'(2013), 'Floor Impact Noise', 'Seoul'(2014), 'Noise'(2015), 'Hedonic Model'(2016). In addition, following research topics are expected to be active in the future: In maturity stage of the research development is going to be 'Apartment Price', 'Space', 'Management of Apartment Housing'; the hedonic model, which is research growth and development stage, is going to be '(Floor Impact) Noise', 'Community', 'Energy.

Health-Promoting Behaviors of the Women Workers at the Manufacturing Industry -Based on the Pender's Health Promotion Model- (제조업 여성 근로자의 건강증진행위 관련 요인 분석 -Pender의 건강증진모형 적용-)

  • Yun, Soon Nyoung;Kim, Jeong Hee
    • Korean Journal of Occupational Health Nursing
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    • v.8 no.2
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    • pp.130-140
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    • 1999
  • The purpose of this study was to identify health promoting behaviors(HPBs) and the related determinants affecting to women workers health based on the New Health Promotion Model by Pender(1996). Data were collected by self-reported questionnaires from 208 women workers at the 8 electronic manufacturing factories under the permission of data collection and cooperation with health managers in the factories during the period from September to October 1999. For data analysis. Descriptive statistics, ANOVA, Pearson's correlation and Stepwise multiple regression with SPSS/PC+7.5 version were used. The results were as follows : 1. The average score for the HPBs, consisted of 6 subdimensions was 2.05. The highest mean score was 2.29 in 'Spiritual growth' and the lowest one was 1.66 in 'Physical activity'. 2. No significant difference between general charateristics and HPBs were found. 3. HPBs were positively related to 'Prior related behavior'(r=0.369, p<0.1), 'Perceived self-efficacy'(r=0.340, p<.01), 'Activity-related affect'(r=0.252, p<.01). 'Social support'(r=0.350, p<.01). 'Commitment to a plan action'(r=0.374, p<.01). There was no significant correlation between perceived health status, perceived barriers to action and HPBs. 4. The most important variable in HPBs was 'Commitment to a plan action'. It was explained 14.0% out of the total variance of HPBs. 'Commitment to a plan action', 'Prior related behavior', 'Social support', 'Self-efficacy' and 'Perceived barriers to action' explained 23.0%. According to the results of this study, the suggestions were as follows: 1. It is necessary to develop program for improving the physical activity and health responsibility of women workers at the manufacturing industry. 2. To facilitate and maintain HPBs of women workers, nurses may enhance and plan mutually interactive active HPBs with women workers. 3. Social support at the level of individual workers, supervisors, and the organization is required in order to conduct health promotion program at the factories. 4. Significantly related variables to HIPBs should be identified the direct and indirect paths among them further more.

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Changes in Endogenous Gibberellin Contents during Bulb Development Period in the Cold-type Cultivar of Garlic (Allium sativum L.) of Korea (한지형 마늘의 인경 발육 과정에서 내생 지베렐린류의 함량변화)

  • Sohn, Eun-Young;Kim, Yoon-Ha;Kim, Byung-Su;Seo, Dong-Hwan;Lee, Hyun-Suk;Lee, In-Jung
    • Horticultural Science & Technology
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    • v.28 no.5
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    • pp.750-756
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    • 2010
  • This study was performed to investigate the role of phytohormones in the bulbing of garlic in order to assess the yield and quality. The effect on endogenous plant hormones such as gibberellin (GA) content was also examined during growth stage i.e. clove differentiation to bulbing in garlic. More than 18 gibberellins in garlic were identified with extensive gas chromatograph-mass spectrometry-selected ion monitoring (GC-MS-SIM) quantitative analysis. The results showed that GAs were biosynthesized by both non C-13 hydroxylation pathway (NCH) and early C-13 hydroxylation pathway (ECH) in garlic plant. It was also revealed that NCH pathway leading to synthesis of bioactive $GA_4$ was the more prominent GA biosynthesis pathway than ECH pathway in which bioactive $GA_1$ was synthesized. Total GAs level was gradually increased from clove differentiation to bulbing and later decreased, which portrays the active role of GA in differentiation. The biosynthesis ratio of bioactive $GA_4$ and $GA_1$ concentration was similar to that of total GAs content, which was closely related with bulb development in garlic.

A Study on the Brand Characteristics According to Trends in the Children's Apparel Market

  • Han, Gyung-Hee
    • Journal of Fashion Business
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    • v.9 no.6
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    • pp.160-174
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    • 2005
  • Despite the decrease in the number of children due to low birth rate, the domestic children's apparel market has been achieving steady growth as family income is rising thanks to more opportunities for working women, parents spend more on their children, and they prefer brand products that make their children look special. In addition, the market is suffering from hard competition as large enterprises have joined the race. The present study purposed to survey the children's apparel market in Korea, which is in a transitional period, and to contribute to the development of the market with Korean brands. For this purpose, we analyzed the characteristics of children's apparel brands in the 21st century based on the current state of the domestic children's apparel market and, based on the findings, forecasted the future trend of children's apparel brands, suggested improvements for expected problems, proposed standards for coping with changes such as diversification, high quality and differentiation in the children's apparel market, and provided consumers with information on how to purchase products. According to the result of analyzing the characteristics of children's apparel brands in the 21st century, brands are categorized largely into four types - life cultural brands, functional product brands, character brands and brands advancing to China. Life cultural brands equipped with all necessities for children are expanding, and with the deepening social problems of environmental pollution and the reduction of the child population, functional products made of environment-friendly materials are spreading widely, targeting infants and children. Furthermore, for extending age targets and diversifying products, children's apparel is using characters. The use of characters is expected to have a considerable effect on the growth of brands because children are more subjective as consumers than before and they are more easily persuaded with characters. Domestic children's apparel brands advancing to China have a high expectation of success in overcoming the limitation of the local market that has reached its peak and growing into global brands. Korean apparel makers are struggling to overcome the depressed domestic market, to recover consumers' consumption, to cope with market opening, to pursue high value of sensibility and to expand the seniors' market, etc. In this situation, future trends of children's apparel brands will be the expansion of family brands, brand totalization, quality price, niche market (pre-teen market), etc. In response to these trends, we made the following suggestions for improvement. 1. Children's apparel brands are evolving into family brands as well as into total brands through voluming. Today, however, apparel makers are advancing to the children's apparel market with the concept of adults' apparel and, as a result, children's apparel is merely adults' apparel of reduced size, having problems in design, color and materials. Thus, apparel makers must develop design considering the wide range of size and the characteristics of children's apparel, strengthen sourcing abilities to create revenues, and make thorough survey of customers to find common denominators between adults' apparel and children's apparel considering that characteristic that the target class is different from the buyer class. Furthermore, they must make active investments in human resources, develop outstanding products through advanced planning and design, and support marketing techniques and management systems to stores. 2. As the declining birth rate will continue to have a negative effect on the market, it may be difficult to expand the market size but there is still a margin for growth through high-sensibility and high-quality products. The competitiveness of brands is determined by their market shares. Accordingly, concepts should be specialized according to lifestyle, customers' diverse needs should be satisfied, and cross-coordination should be achieved within a brand. 3. Considering Korean parents who do not spare investment in their children despite shrinking consumption, functional products must be high value-added goods that can enhance efficiency. However, in the current situation of the infants' apparel industry where a textile manufacturer supply its products to multiple brands, it is difficult to develop unique products only based on materials. Thus, it is considered urgent to appeal to consumers not by relying on materials only but by finding methods of applying their own characters to children's dress.

Ecological Studies on the Transition of Sheath Blight of Rice in Korea (한국(韓國)에서의 벼 잎집무늬마름병 발생변동(發生變動)에 관(關)한 생태학적(生態學的) 연구(硏究))

  • Yu, Seung-hun
    • Korean Journal of Agricultural Science
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    • v.4 no.2
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    • pp.283-316
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    • 1977
  • In an attempt to obtain a basic information to develop an effective integrated system of controlling sheath blight of rice in Korea, the transition of this disease, the variation of cultural characters and pathogenicity of the pathogen, environmental conditions affecting the disease outbreak and varietal resistance have been investigated. 1. Rice sheath blight which has been minor disease in the past was widely spread, especially since 1971. This disease has promptly spread all over the country and infected 65.2% of total rice growing area in 1976. Various factors are considered to be related to such transition of this disease. Above all, increace of application of nitrogenous fertilizer, early season and earlier cultivation of rice, introduction of more susceptible "Tongil" varieties etc. must be important factors influencing the outbreak of this disease. 2. Great variations in cultural characteristics-such as mycelial growth rate, color of the medium, amount of the aerial mycelium, shape and color of the sclerotia- and in the pathogenicity of isolates of the pathogen, Thanatephorus cucumeris Dank were observed. The optimum temperature for mycelial growth also varied with isolates, from $25^{\circ}C$ to $30^{\circ}C$. There were not necessarily any correlation between curtural characteristics and pathogenicity of isolates of Thanatephorus cucumens. 3. Mycelial grow th of isolates of Thanatephorus cucumens on the PDA medium were correlated with the air temperatures of the region where the isolates were collected. The isolates from the regions with high temperature grew well on PDA medium at $35^{\circ}C$ than those from the region with low temperature, on the other hand, the isolates from the regions with the low temperature grew well on the same medium at $12^{\circ}C$ than those from the regions with high temperature. 4. Pectin polygalacturonase (PG) and cellulase (Cx) were most active on the 3rd day after inoculation on the leaves of rice plant with Thanatephorus cucumeris, whereas pectin methylestrase (PE) was most active on the 4th day after inoculation. Relationship between the activities of PE of isolates and the strength of pathogenicity of isolates was obtained, but PG and cellulase activities were not correlated with pathogenicity of isolates. 5. The tolerence of sclerotia from in-vitro culture to low temperature varied with their water content, the dried cultural sclerotia were more tolerent than wet ones, Dried cultural sclerotia maintained almost 100% germinability for 45 days at $-20^{\circ}C$, whereas wet sclerotia lost viability at $-5^{\circ}C$. The germination ratio of the sclerotia after overwintering changed from 18% to 70% according to the water content of the test paddy fields and the ratio was low in wet paddy condition. 6. To investigate the host range of this fungi in and near paddy field, 17 weeds were inoculated with fungi. The lesions of sheath blight disease was obserbed on Sagittaria trifolia L., Echinochloa crusgalli P. Beauv., Monochoria vaginal is Presl, Polygonum Hydropiper L., Eclipta prostrata L., Digitaria sanguinalis Scapoli. 7. When the level of nitrogen applied was doubled over standard level, total nitrogen content in rice sheath increased, ami when silicate was applied, starch content in rice sheath decreased, inducing the rice plants more susceptible to sheath blight disease. Increased dressing of potash ferilizer reduced the incidence of sheat blight disease. 8. The percentage of infected stems in the early period increased more in the narrow hill plot than in the wide hill plot, but in the late period this tendency was inversed; the percentage of infected stems as well as severity in the wide hill plot increased more compared to the narrow hill plot, and the disease severity in the one plant per hill plot was also low. The number of stems in the wide hill plot was more than the number of stems in the narrow hill plot. This indicates that the microclimate, such as the relative humidity, in the narrow hill plot was more favorable for the development of this disease. 9. There was a high negative correlation between the disease severity of varieties to the sheath blight and the maturity of the varieties, that is, the early varieties were more susceptible than the late ones, and much-tillering varieties usually showed more infection than less tillering varieties. 10. No relationship was obtained between the percentage of infected stems in the early period and the severity after heading, whereas a distinct relationship was obtained between former and latter after Aug. 10.

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