• Title/Summary/Keyword: eIF5A

Search Result 916, Processing Time 0.034 seconds

결장루형성술 환자 간호를 위한 일 연구

  • 모경빈
    • Journal of Korean Academy of Nursing
    • /
    • v.1 no.1
    • /
    • pp.27-43
    • /
    • 1970
  • This study is designed to find out proper nursing activities for the needs of the colostomy patients, i.e., mental and psychological as well as physical needs for rapid recovery, and to help them build up the follow-up care for proper social adjustment. The study is based on 268 cases out of 381 colostomy patient's records kept in Ewha Womans University Hospital, Yonsei Medical Center, and National Medical Center in between the period from Jan. 1953 to Jan. 1970. The items of study are mainly on etiology, sex, age, duration of hospitalization, mortality rate, seasonal frequency, time from the onset of illness to the admission of the hospital, signs and symptoms. 1. Frequency of onset by etiology: Neoplastic disease 112 cases (42%), Inflammatory disease 33 cases (12%), Congenital malformation 30 cases (11%), Intussusception 25 cases (9.3%), Trauma 24 cases (9%), Volvulus 17 cases (6.3%), and Crohn's disease 6 cases (2.2%). 2. By sex: male 167 cases (62.9%), and female 101 cases (37.1%). So the ratio of portion of male and female 2:1. 3. By age: under 1·year·old 27 cases (10.1%) highest, 41-50 yrs 54 cases (20.2%), 51-60 yrs 42 cases (15.5%), above 71 yrs 5 cases (1.9%). 4. Duration of hospitalization: the shortest is 2-days and the longest is 470 days. 1-20-days 52%, 40-60 days 14%. 5. Mortality rate: Under the 10-days-admission 19.5%, and the beyond 30-days-admission 3.9%. 6. Seasonal frequency: Higher in summer (32% ). 7. Signs and symptoms: abdominal pain (56%), abdominal distention (54%), vomiting (40%), bloody mucoid diarrhea (38%) , pain of anal region (18%), abdominal tenderness, anorexia, indigestion, constipation, disuria, tenesmus, high fever and chilling sensation, bile tingled vomiting. Nursing activities for the patient's physical needs are as follows: Skin care for colostomy region, Prevention of colostomy constriction and depression, Removal of an offensive odor, The use of colostomy bag-selection for, and demonstration of the use of inexpensive colostomy irrigation equipment, Personal hygiene, general skin care, care of hair, finger nails and toe-nails, Oral hygiene, sleep and rest, aquate, Daily activities, etc. Measures for regulation of bowl movement. Keeping the instruction of taking food, Preparing the meal and help for anorexia, Constipation and it's solution, Prevention of diarrhea, helping the removal of mucous, and stretch constricted steam as needed. Nursing activities for pt's socio-psychological needs are as follows; Help the patient to make decision for the operation, Remove pt's anxiety toward operation and anesthesia, To meet the pt's spiritual needs at his death bed, Help to establish family and friends cooperation, Help to reduce anxiety at the time of admission and it's solution, Help to meet religious need, Help to remove pt's anxiety for loosing his job and family maintenance, Follow-up studies for 7 cases have been done to implement the present thesis. The items of the personal interviews with the patients are as follows: Acceptability for artificial anus, The most anxious thing they had in mind at the time of discharge, The most anxious thing they hat·e in mind at present, Their friends and family's attitudes toward the patient after operation, Relations with other colostomy patients, Emotional damage from the operation, Physical problem of enema, irrigation, Control of diet, Skin care, Control of offensive odor, Patient's suggestions to nurses during hospital stay and after discharge. In conclusion, the follow-up care for colostomy patients shares equal weight or perhaps more than the post-operative care. The follow-up care should include the spiritual care for moral support of the patient, to drag him out of isolation and estrangement, and make him fully participate in social activities. It is suggested that the following measures would help to rehabilitate the colostomy patients (1) mutual acquaintance with other colostomy patients if possible form a sort of club for the colostomy patient to exchange their experiences in care (2) through the team work of doctor, nurse and rehabilitation specialists, to have a sort of concerted effort for betterment of the patient.

  • PDF

Evaluate Utility of Thyroid Cancer Discrimination by 18F-FDG PET/CT Delay Scan Images (18F-FDG PET/CT검사에서 지연영상을 이용한 갑상선암 진단의 유용성 평가)

  • Lee, Hyeon-Guck;Han, Man-Seok;Kim, Yong-Kyun;Seo, Sun-Youl;Jeon, Min-Cheol;Kim, Tae-Hyung;Hong, Seong-Jong
    • Journal of the Korea Academia-Industrial cooperation Society
    • /
    • v.14 no.6
    • /
    • pp.2958-2965
    • /
    • 2013
  • Purpose : To evaluate the degree of malignancy of incident thyroid lesion found in 18F-FDG PET/CT findings and the usefulness of the method suggested in this study, we applicate the Delay Scan Method that differentiate a false positive benign tumor, inflammation and malignancy, as well as make the criteria of SUV. Materials and Methods : A retrograde study was conducted of 25 patients(1 exception) who were admitted in E hospital to receive 18F-FDG PET/CT examination until Janaary and April of 2008. 18F-FDG PET/CT image photographing was taken in Biograph-Duo made by SIEMENS, after taking normal 18F-FDG PET/CT image(1hr) and then 1hr later we took the thyroid 1 bed-delayed image for the patients who showed abnormal thyroid 18F-FDG uptake and above 2.0 SUV for 2 minutes every 1 bed. For the patients who showed abnormal thyroid uptake and above 2.0 SUV, 1hr later, we took a 1 bed-delayed image and then made a comparative study between measured maxSUV of 1hr-abnormal uptake image and that of 2hr-delayed image. Results : In this 18F-FDG PET/CT study among the patients who showed incidental 18F-FDG thyroidal uptake the number of thyroid cancer was 5(20.8%), all of then showed benign findings. a comparison of results for 18F-FDG PET/CT. the benign patient measured maxSUV in the PET/CT. image(1hr) mean value 5.06maxSUV and delay image(2hr) mean value 5.23maxSUV differences of two value is 0.19maxSUV and the malignantIt patient measured maxSUV in the PET/CT. image(1hr) mean value 9.63maxSUV and delay image(2hr) mean value 10.65maxSUV differences of two value is 10.65maxSUV in Thyroid abnormal uptake patients. Conclusion : in the case of incidental 18F-FDG uptake in thyroid, max SUV of focal thyroid lesion is above 5.0 if 18F-FDG PET/CT examine the delayed images to add, You could see that reasonable diagnostic method useful. to differentiate whether lesions of malignant.

Spectrophotometric analysis of the influence to shade of zirconia core on the color of ceramic (지르코니아 코아의 색조부여가 전부도재관의 색조에 미치는 영향에 대한 분광측색분석)

  • Baek, Ki-Hyun;Woo, Yi-Hyung;Kwon, Kung-Rock;Kim, Hyeong-Seob
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.46 no.4
    • /
    • pp.409-419
    • /
    • 2008
  • Statement of problem: At all times people have tried to fabricate tooth restorations using tooth colored materials. Recently, demands for esthetics, even in restorations requiring strength, has brought a revolution to dentistry and increased use of zirconia. The basic color of zirconia is white to ivory. The color can be partially adapted by veneering it with ceramic materials. However, it would be better if the substructure could already be adapted to the basic color shade of neighboring teeth. By adaptation to the basic shade, it can help to reduce the necessary layer thickness of the veneer ceramic to achieve the desired color. Purpose: The purpose of this study was to spectrophotometrically evaluate the influence of shading of zirconia core on the final shade of all-ceramic restorations using the CIE $L^{*}a^{*}b^{*}$ system. Material and methods: Core specimens (n = 20 per group) of Lava Frame Zirconia, KaVo Everest Zirconia, Digident CAD/CAM Zirconia were fabricated at 20 mm in diameter and 0.5 mm in thickness. Halves of each groups were shaded in A3 color. These core specimens were veneered with A3 porcelain of the recommended manufacturer at thickness of 0.5 mm. CIE $L^{*}a^{*}b^{*}$ coordinates were recorded for each specimen with a spectrophotometer (Model CM-2600d, Minolta, Japan) at 0.5 mm, 0.4 mm, 0.3 mm in thickness. Color differences were calculated using the equation ${\Delta}E^{*}=[({\Delta}L^{*})2+({\Delta}a^{*})2+({\Delta}b^{*})2]1/2$. Results: 1. In the case where porcelain layer has a thickness of 0.5 mm, Lava Frame Zirconia and KaVo Everest group did not show clinically perceived color difference, however Digident CAD/CAM Zirconia group showed clinically perceived color difference according to shade allowed on core. 2. When the thickness of porcelain layer decreased from 0.5 mm to 0.4 mm, Lava Frame Zirconia and KaVo Everest group did not show clinically perceived color difference, on the other hand Digident CAD/CAM Zirconia group showed clinically perceived color difference according to shade allowed on core. 3. When the thickness of porcelain layer decreased from 0.5 mm to 0.3 mm, clinically perceived color differences were observed from all three groups. Conclusions: Ziroconia system, which is possible to allow shade on core, are thought to be much more favorable to reproduce natural shade compared to systems that is impossible to give shade. Therefore, clinicians ought to choose adequate system for certain clinical situation by considering above specific character.

STUDIES ON THE DIMORPHISM OF THE PERSICARIA SENTICOSA NAKAI (Persicaria senticosa Nakai의 Dimorphism에 관한 연구)

  • HARN, Chang Yawl
    • Journal of Plant Biology
    • /
    • v.3 no.1
    • /
    • pp.16-25
    • /
    • 1960
  • HARN, Chang Yawl (Chonnam U. Kwangju, Korea): Siudies on the dimorpism of the Perisicaria senticosa Nakai-Kor. jour. Bot. 3(1) 16-25 During his researches regarding the morphological and physiological properties of Polygonecenae, the author has found that the species, Persicaria senticosa, aiso, besides the heterostylous plants of Polygonum family, Fagopyrum esculentum, and Persicaria japonica which was recently verified by the author as dimorphic, shows the typical floral structure of heterostylism, the description of which is not found in taxonomical works. Further research on this species have revealed that this plant, despite pressessing characteristic structural dimorphism, does not exhibit even the slight signs of heterostlylous properties physiologically. This is a deviation from the usual behavior of normal heterostylous plants. What is interesting is the fact that the physiological behavior of this species is quite contrary to that of P. japonica which is considered to be the most highly specialized dimorphic plant. Thus it is assurred that if some species of this family had taken a heterostylic form in its course of development from autogamy to allogamy, P. seoticosa would be the least differentiated type of dimorphic forms among the three heterostylous plants, including buckwheat, of this family. The results obtained in this experiment are summarized as follows: 1) P. senticosa has two forms of flower, one, long style-short stamened; the other, short style-long stamened. Not only conspicuous is this primary difference, but the secondary difference, such as pollen grain size, is noticeable between long and short styled individuals, thus expressing structurally the definite trait of a dimorphic plant. 2) Structural alteration of floral parts towards dimorphism has preceeded far less in comparison with those of the P. japonica and F. esculentum. 3) Elaborate studies on fertility reveal that this species does not show the slightest sign of the physiological characteristics of dimorphic plants. In other words, regardless of the modes of combinations, legitimate and illegitimate, fertilization and fruit setting flourish unimpaired. 4) Growth of pollen tubes apparently parallels the results in the fertility, tubes reaching ovary approximately 30 minutes after pollination both in legitimate and illegitimate combinations. Pollen tube penetration appears to be comparatively rapid. 5) A slight difference in the growth of pollen tube seems to exist between legitimate and illegitimate combinations, legitimate union giving slightly faster tube penetration. 6) In the present experiment it was clarified that P. senticosa, known to possess one form of flower in taxonomy, is in reality dimorphic plant having two of flowers. Although this species is definitely heterostylous in floral structure, physiological evidence and pollen tube behavior show that the differentiation of this plant toward the dimorphism has apparently proceeded slightly except for some parts of floral organ. In ordinary heterostylous plants it is a matter of common occurrence that when illegitimately cmbined, there is poor or no fertility, Contrary to the universal property of heterostylous plants, no difference is observed in the fertility and pollen tube growth between the legitimate and illegitimate combinations in the case of P. senticosa. Compared to the P. japonica and F. esculentum, which are supposed to have undergone high degree of dimorphic differentiation, it is an unavoidable conclusion that P. senticosa has not yet developed as a heterostyle plant except for some of its floral parts. If P. japonica is assumed to be the most differentiated type of hetenostylous plant, thenthe P. senticosa would be regarded as the primitive, retaining still the self-fertile nature so common to the Polygonum genus. In nature, however, this plant has a better chance to be pollinated legitimately owing to the two forms of flowers than to be pollinated illegitimately. The author is indebted to Dong Chul, Kim as well as other members of the Department of Plant Breeding and Genetics of Chonnam National University for their efforts out the laborious experiments during the course of the present studies.

  • PDF

A Multicenter Study of Pertussis Infection in Adults with Coughing in Korea: PCR-Based Study

  • Park, Sunghoon;Lee, Myung-Gu;Lee, Kwan Ho;Park, Yong Bum;Yoo, Kwang Ha;Park, Jeong-Woong;Kim, Changhwan;Lee, Yong Chul;Park, Jae Seuk;Kwon, Yong Soo;Seo, Ki-Hyun;Kim, Hui Jung;Kwak, Seung Min;Kim, Ju-Ock;Lim, Seong Yong;Sung, Hwa-Young;Jung, Sang-Oun;Jung, Ki-Suck
    • Tuberculosis and Respiratory Diseases
    • /
    • v.73 no.5
    • /
    • pp.266-272
    • /
    • 2012
  • Background: Limited data on the incidence and clinical characteristics of adult pertussis infections are available in Korea. Methods: Thirty-one hospitals and the Korean Centers for Disease Control and Prevention collaborated to investigate the incidence and clinical characteristics of pertussis infections among adults with a bothersome cough in non-outbreak, ordinary outpatient settings. Nasopharyngeal aspirates or nasopharyngeal swabs were collected for polymerase chain reaction (PCR) and culture tests. Results: The study enrolled 934 patients between September 2009 and April 2011. Five patients were diagnosed as confirmed cases, satisfying both clinical and laboratory criteria (five positive PCR and one concurrent positive culture). Among 607 patients with cough duration of at least 2 weeks, 504 satisfied the clinical criteria of the US Centers for Disease Control and Prevention (i.e., probable case). The clinical pertussis cases (i.e., both probable and confirmed cases) had a wide age distribution ($45.7{\pm}15.5$ years) and cough duration (median, 30 days; interquartile range, 18.0~50.0 days). In addition, sputum, rhinorrhea, and myalgia were less common and dyspnea was more common in the clinical cases, compared to the others (p=0.037, p=0.006, p=0.005, and p=0.030, respectively). Conclusion: The positive rate of pertussis infection may be low in non-outbreak, ordinary clinical settings if a PCR-based method is used. However, further prospective, well-designed, multicenter studies are needed.

Loran-C Multiple Chain Positioning using ToA Measurements (ToA 측정치를 이용하는 Loran-C 다중 체인 측위 방법)

  • Kim, Youngki;Fang, Tae Hyun;Kim, Don;Seo, Kiyeol;Park, Sang Hyun
    • Journal of Navigation and Port Research
    • /
    • v.43 no.1
    • /
    • pp.23-32
    • /
    • 2019
  • In this paper, we proposed a multi-chain Time of Arrival (ToA) positioning method to estimate positions using all received Loran-C signals from multiple chains without constraining to a single chain. Conventionally, we have to choose only one chain among several available chains for position estimation using Loran-C. Therefore, the number of signals to be used for positioning is limited to three to five. In general, if more signals are used for positioning estimation, its performance tends to be improved in terms of accuracy and availability. To validate the proposed method for multi-chain Loran-C, we firstly carried out a static positioning test in land. By analyzing the test results, we confirmed that the proposed method works well under a multi-chain Loran-C scenario. Subsequently, another mobile positioning test was conducted on board a vessel under a practical application scenario. From this second test, we successfully demonstrated that the multi-chain ToA positioning method even in situations where the conventional single-chain Loran-C approach fails for positioning.

Studies on the Shade Tolerance, Light Requirement, and Water Relations of Economic Tree Species(III) - Analysis of Pressure-Volume Curves on the Changes of Tissue Water Relations of Five Deciduous Hardwood Species Subjected to Artificial Shading Treatments - (주요경제수종(主要經濟樹種)의 내음성(耐陰性) 및 광선요구도(光線要求度)와 수분특성(水分特性)에 관한 연구(III) - 인공피음처리하(人工被陰處理下)에서 자라는 활엽수(闊葉樹) 5수종(樹種)의 수분특성(水分特性) 변화(變化)에 대한 P-V곡선(曲線) 분석(分析) -)

  • Choi, Jeong Ho;Kwon, Ki Won
    • Journal of Korean Society of Forest Science
    • /
    • v.90 no.4
    • /
    • pp.524-534
    • /
    • 2001
  • The pressure-volume curve parameters were investigated to elucidate the effects of shading treatment on the water relations of the one year old seedlings of Betula platyphylla var. japonica, Betula schmidtii, Zelkova serrata, Acer mono and Prunes sargentii subjected to five levels of artificial shading treatments. The osmotic potentials at full turgor(${\phi}_{{\pi}o}$) measured under full sunlight changed with species and growing season in the ranges of -1.04~-1.27MPa, -1.03~-1.48MPa, -0.94~-1.44MPa in first year treatment, and -0.90~-1.37MPa, -1.05~-1.79MPa, -0.99~-1.30MPa in second year treatment in June, July, and September, respectively. The osmotic potentials at full turgor increased with increment of shading level in the ranges of -0.90~-1.79MPa in full sunlight and -0.58~-1.23MPa in nearly full shading level(E) through the growing seasons in all the species studied. The osmotic potentials at turgor loss point(${\phi}_{{\pi}p}$) measured in full sunlight changed in the ranges of -1.64~-2.11MPa, -1.67~-2.15MPa, -1.47~-2.11MPa, and -1.45~-2.04MPa, -1.30~-2.00MPa, -1.28~-2.33MPa in June, July, and September of first and second years, respectively. Most of ${\phi}_{{\pi}p}$ measurements were lower within about 0.5MPa in comparison with those of ${\phi}_{{\pi}o}$. The measurements of ${\phi}_{{\pi}p}$ also increased with increment of shading level, and the differences in ${\phi}_{{\pi}p}$ among shading levels were generally greater than those in ${\phi}_{{\pi}o}$ by species and by growing season. Most of the osmotic potentials at turgor loss point as like as at full turgor were lowered in July than in June and September. The measurements of relative water content at turgor lass point(RWCp) in full sunlight were in the similar ranges of 81~88%, 71~86%, 75~84%, and 82~87, 72~84%, 76~86% in June, July, and September of first and second years, respectively. The RWCp were a little higher in A. mono and P. sargentii than in B. platyphylla var. japonica, B. schmidtii, and Z. serrata. The RWCp also decreased from 71~88% in full sunlight to 48~77% in nearly full shading treatment with increment of shading level. Even if there were some exceptions by species or by growing season, the shading effects on the changes in some P-V parameters were distinctly observed in the present study. The change in P-V parameters following shading treatment may be presumably inferred on the changes in solute accumulation, membrane elasticity, symplasmic water volume, and so on. But much more experiments should be necessarily continued for getting detailed informations on the physiological mechanism of shading effects relating to the changes in P-V parameters.

  • PDF

A Study for Factors Influencing the Usage Increase and Decrease of Mobile Data Service: Based on The Two Factor Theory (모바일 데이터 서비스 사용량 증감에 영향을 미치는 요인들에 관한 연구: 이요인 이론(Two Factor Theory)을 바탕으로)

  • Lee, Sang-Hoon;Kim, Il-Kyung;Lee, Ho-Geun;Park, Hyun-Jee
    • Asia pacific journal of information systems
    • /
    • v.17 no.2
    • /
    • pp.97-122
    • /
    • 2007
  • Conventional networking and telecommunications infrastructure characterized by wires, fixed location, and inflexibility is giving way to mobile technologies. Numerous research reports point to the ultimate domination of wireless communication. With the increasing prevalence of advanced cell-phones, various mobile data services (hereafter MDS) are gaining popularity. Although cellular networks were originally introduced for voice communications, statistics indicate that data services are replacing the matured voice service as the growth engine for telecom service providers. For example, SK Telecom, the Korea's largest mobile service provider, reported that 25.6% of revenue and 28.5% of profit came from MDS in 2006 and the share is growing. Statistics also indicate that, in 2006, the average revenue per user (ARPU) for voice didn't change but MDS grew seven percents from the previous year, further highlighting its growth potential. MDS is defined "as an assortment of digital data services that can be accessed using a mobile device over a wide geographic area." A variety of MDS have been deployed, with a few reaching the status of killer applications. Many of them need to access the Internet through the cellular-phone infrastructure. In the past, when the cellular network didn't have acceptable bandwidth for data services, SMS (short messaging service) dominated MDS. Now, Internet-ready, next-generation cell-phones are driving rich digital data services into the fabric of everyday life, These include news on various topics, Internet search, mapping and location-based information, mobile banking and gaming, downloading (i.e., screen savers), multimedia streaming, and various communication services (i.e., email, short messaging, messenger, and chaffing). The huge economic stake MDS has on its stakeholders warrants focused research to understand associated dynamics behind its adoption. Lyytinen and Yoo(2002) pointed out the limitation of traditional adoption models in explaining the rapid diffusion of innovations such as P2P or mobile services. Also, despite the increasing popularity of MDS, unexpected drop in its usage is observed among some people. Intrigued by these observations, an exploratory study was conducted to examine decision factors of MDS usage. Data analysis revealed that the increase and decrease of MDS use was influenced by different forces. The findings of the exploratory study triggered our confirmatory research effort to validate the uni-directionality of studied factors in affecting MDS usage. This differs from extant studies of IS/IT adoption that are largely grounded on the assumption of bi-directionality of explanatory variables in determining the level of dependent variables (i.e., user satisfaction, service usage). The research goal is, therefore, to examine if increase and decrease in the usage of MDS are explained by two separate groups of variables pertaining to information quality and system quality. For this, we investigate following research questions: (1) Does the information quality of MDS increase service usage?; (2) Does the system quality of MDS decrease service usage?; and (3) Does user motivation for subscribing MDS moderate the effect information and system quality have on service usage? The research questions and subsequent analysis are grounded on the two factor theory pioneered by Hertzberg et al(1959). To answer the research questions, in the first, an exploratory study based on 378 survey responses was conducted to learn about important decision factors of MDS usage. It revealed discrepancy between the influencing forces of usage increase and those of usage decrease. Based on the findings from the exploratory study and the two-factor theory, we postulated information quality as the motivator and system quality as the de-motivator (or hygiene) of MDS. Then, a confirmative study was undertaken on their respective role in encouraging and discouraging the usage of mobile data service.

Evaluation of the color reproducibility of all-ceramic restorations fabricated by the digital veneering method

  • Kim, Jae-Hong;Kim, Ki-Baek;Kim, Woong-Chul;Kim, Hae-Young;Kim, Ji-Hwan
    • The Journal of Advanced Prosthodontics
    • /
    • v.6 no.2
    • /
    • pp.71-78
    • /
    • 2014
  • PURPOSE. The objective of this study was to evaluate the clinical acceptability of all-ceramic crowns fabricated by the digital veneering method vis-$\grave{a}$-vis the traditional method. MATERIALS AND METHODS. Zirconia specimens manufactures by two different manufacturing method, conventional vs digital veneering, with three different thickness (0.3 mm, 0.5 mm, 0.7 mm) were prepared for analysis. Color measurement was performed using a spectrophotometer for the prepared specimens. The differences in shade in relation to the build-up method were calculated by quantifying ${\Delta}E^*$ (mean color difference), with the use of color difference equations representing the distance from the measured values $L^*$, $a^*$, and $b^*$, to the three-dimensional space of two colors. Two-way analysis of variance (ANOVA) combined with a Tukey multiple-range test was used to analyze the data (${\alpha}$=0.05). RESULTS. In comparing means and standard deviations of $L^*$, $a^*$*, and $b^*$ color values there was no significant difference by the manufacturing method and zirconia core thickness according to a two-way ANOVA. The color differences between two manufacturing methods were in a clinically acceptable range less than or equal to 3.7 in all the specimens. CONCLUSION. Based on the results of this study, a carefully consideration is necessary while selecting upper porcelain materials, even if it is performed on a small scale. However, because the color reproducibility of the digital veneering system was within the clinically acceptable range when comparing with conventional layering system, it was possible to estimate the possibility of successful aesthetic prostheses in the latest technology.

A study on sprouting of a young merchantable pitch pine stand (장령기(壯令期)에 가까운 리기다소나무 임분(林分)의 맹아(萌芽) 갱신(更新)에 대(對)한 연구(硏究))

  • Park, Tai Sik
    • Journal of Korean Society of Forest Science
    • /
    • v.1 no.1
    • /
    • pp.22-29
    • /
    • 1962
  • (1) The objects of this study are to observe the possibility of regenerating a young merchantable pitch pine stand by sprouts and to compare the growth trend of sprouts with that of seedlings of same age grown under the almost same circumstances. (2) A plot of 20 year old pitch pine plantation, i.e. 200 trees on 0.1 ha of average D.B.H. 14 cm was clearcut at 20 cm above ground in April, 1945. By the late spring of that year sixty per cent of the cut stumps had sprouted. (3) Fourty to eighty sprouts were found on each stump (maximum:412 sprouts) at the first, but many of them had gradually died out leaving only four to five sprouts per stump by the time of three years after cutting. At that time only one vigorous sprout was left per stump by eliminating the weaker ones. (4) The sprouts, as they grew, started to cover the old stumps with new tissues developed from lower part of sprouts;consequently forming new root systems from the base of new tissues, and they appeared to be seedlings. When the age of sprouts was thirteen years old, the old stumps were completely decayed away and the reproduced stand from sprouts was averaged at 9.7 cm in D.B.H. and at 5.5m in height. (5) When the age of sprouts was thirteen years old, the sprouts exceeded the seedlings in both of total present growth and mean annual increment in height, volume, D.B.H. and basal area, but the seedlings began to exceed the sprouts in current annual increment of height, volume, D.B.H. and basal area at about ten years of age. The rates of increment of the seedling in height, volume, ect. were larger than those of sprouts except when they were one to four years old. From above facts, the following may be concluded: (1) In regenerating a pitch pine stand by sprouts, the lower the stump height, the better the result. (2) If no light limit exists, regenerating a pitch pine stand by sprouts is well possible even at the age of 20 year. (3) Pitch pine reproduction started from sprouts exceeds the seedlings of same age in growth under the almost same circumstances until they get ten years of age.