• Title/Summary/Keyword: Isolation

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Plasma Activity of Lysosomal Enzymes in Active Pulmonary Tuberculosis (활동성 폐결핵 환자에서 혈중 리소솜 효소의 활성도)

  • Koh, Youn-Suck;Choi, Jeong-Eun;Kim, Mi-Kyung;Lim, Chae-Man;Kim, Woo-Sung;Chi, Hyun-Sook;Kim, Won-Dong
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.5
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    • pp.646-653
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    • 1995
  • Background: The confirmative diagnosis of pulmonary tuberculosis(Tb) can be made by the isolation of Mycobacterium Tuberculosis(MTb) in the culture of the sputum, respiratory secretions or tissues of the patients, but positive result could not always be obtained in pulmonary Tb cases. Although there are many indirect ways of the diagnosis of Tb, clinicians still experience the difficulty in the diagnosis of Tb because each method has its own limitation. Therefore development of a new diagnostic tool is clinically urgent. It was reported that silica cause some lysosomal enzymes to be released from macrophages in vitro and one of these enzymes is elevated in workers exposed to silica dust and in silicotic subjects. In pulmonary Tb, alveolar macrophages are known to be activated after ingestion of MTb. Activated macrophages can kill MTb through oxygen free radical species and digestive enzymes of lysosome. But if macrophages allow the bacilli to grow intracellularly, the macrophages will die finally and local lesion will enlarge. Then it is assumed that the lysosomal enzymes would be released from the dead macrophages. The goal of this investigation was to determine if there are differences in the plasma activities of lysosomal enzymes, ($\beta$-glucuronidase(GLU) and $\beta$-N-acetyl glucosaminidase(NAG), among the groups of active and inactive pulmonary Tb and healthy control, and to see if there is any possibility that the plasma activity of GLU and NAG can be used as diagnostic indicies of active pulmonary Tb. Methods: The plasma were obtained from 20 patients with bacteriologically proven active pulmonary Tb, 15 persons with inactive Tb and 20 normal controls. In 10 patients with active pulmonary Tb, serial samples after 2 months of anti-Tb medications were obtained. Plasma GLU and NAG activities were measured by the fluorometric methods using 4-methylumbelliferyl substrates. All data are expressed as the mean $\pm$ the standard error of the mean. Results: The activites of GLU and NAG in plasma of the patients with active Tb were $21.52{\pm}3.01$ and $325.4{\pm}23.37$(nmol product/h/ml of plasma), respectively. Those of inactive pulmonary Tb were $24.87{\pm}3.78$, $362.36{\pm}33.92$ and those of healthy control were $25.45{\pm}4.05$, $324.44{\pm}28.66$(nmol product/h/ml of plasma), respectively. There were no significant differences in the plasma activities of both enzymes among 3 groups. The plasma activities of GLU at 2 months after anti-Tb medications were increased($42.18{\pm}5.94$ nmol product/h/ml of plasma) in the patients with active pulmonary Tb compared with that at the diagnosis of Tb(P-value <0.05). Conclusion: The results of the present investigation suggest that the measurement of the plasma activities of GLU and NAG in the patients with active pulmonary Tb could not be a useful method for the diagnosis of active Tb. Further investigation is necessary to define the reasons why the plasma activities of the GLU was increased in the patients with active pulmonary Tb after Tb therapy.

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Microbiological Studies on Feed Supplements (사료첨가제(飼料添加劑)의 미생물오염(微生物汚染)에 관(關)하여)

  • Park, Su Kyung;Tak, Ryun Bin
    • Current Research on Agriculture and Life Sciences
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    • v.4
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    • pp.132-140
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    • 1986
  • Eighty one products from 36 kinds of vitamin and mineral feed supplement collected during August, 1984 to February, 1985 were examined for microbiological contamination. In addition, 83 strains of coliform isolated from the samples were tested for the resistance to 8 kinds of antimicrobial drugs and distribution of R plasmid. General bacteria were detected in all of samples tested. Bacterial population was varied from less than 10 per gram of the sample to 1,400,000 per gram and 34 (42%) of 81 samples were contaminated with 100 to 1,000 cells per gram. Coliform isolation, which was more frequent in samples with larger number of general bacteria, was possible in 14 (17.3%) out of 81 samples tested and 6 (33.3%) out of 18 companies were coliform positive in their products. Forty one (49.4%) out of 83 coliform isolates were fecal coliform. The frequency of resistant strains was the highest to sulfadimethoxine (Sa) with 92.8% and followed by streptomycin (Sm, 67.5%), tetracycline (Tc, 50.6%), kanamycin (Km, 26.5%), chloramphenicol (Cm, 18.1%) and ampicillin (Am, 15.7%). No strain was resistant to nalidixic acid (Na) and gentamicin (Gm). The resistance frequency of fecal coliform strains were higher compare to non-fecal coliform strains. There were minimum inhibitory concentration (MIC) of $3,200{\mu}g/m{\ell}$ or higher in 7 strains to Am, 3 to Sm and 3 to Km, and 70 strains had MIC of $1,600{\mu}g/m{\ell}$ of higher to Sa while Tc had MICs from $1.6{\mu}g/m{\ell}$ to $400{\mu}g/m{\ell}$. All strains had MICs of $6.3{\mu}g/m{\ell}$ of lower to Na and $3.1{\mu}g/m{\ell}$ of lower to Gm. Seventy nine (95.2%) of 83 strains were resistant to one or more drugs tested. The most frequent resistance patterns were SaSm (14.5%) and followed by SaSmTc(12%), SaSmTcKm(8.4%) SaTc (8.4%) and SaSmKm (7.2%) ; total 19 different patterns were noted. Thirty two (40.5%) of 79 resistant strains were transferred all of a part of their resistance to Escherichia coli ML 1410. The frequency of transferable resistance was high in Am (100%) and Cm (80%) while low in Tc (38.1%), Sa (18.2%), Sm (17.9%) and Km (4.5%).

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The Effects of Storage of Human Saliva on DNA Isolation and Stability (인체타액의 보관이 DNA 분리와 안정도에 미치는 영향)

  • Kim, Yong-Woo;Kim, Young-Ku
    • Journal of Oral Medicine and Pain
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    • v.31 no.1
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    • pp.1-16
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    • 2006
  • The most important progress in diagnostic sciences is the increased sensitivity and specificity in diagnostic procedures due to the development of micromethodologies and increasing availability of immunological and molecular biological reagents. The technological advances led to consider the diagnostic use of saliva for an array of analytes and DNA source. The purpose of the present study was to compare DNA from saliva with those from blood and buccal swab, to evaluate diagnostic and forensic application of saliva, to investigate the changes of genomic DNA in saliva according to the storage temperature and period of saliva samples, and to evaluate the integrity of the DNA from saliva stored under various storage conditions by PCR analysis. Peripheral venous blood, unstimulated whole saliva, stimulated whole saliva, and buccal swab were obtained from healthy 10 subjects (mean age: $29.9{\pm}9.8$ years) and genomic DNA was extracted using commercial kit. For the study of effects of various storage conditions on genomic DNA from saliva, stimulated whole saliva were obtained from healthy 20 subjects (mean age: $32.3{\pm}6.6$ years). After making aliquots from fresh saliva, they were stored at room temperature, $4^{\circ}C$, $-20^{\circ}C$, and $-70^{\circ}C$. Saliva samples after lyophilization and dry-out procedure were stored at room temperature. After 1, 3, and 5 months, the same experiment was performed to investigate the changes in genomic DNA in saliva samples. In case of saliva aliquots stored at room temperature and dry-out samples, the results in 2 weeks were also included. Integrity of DNA from saliva stored under various storage conditions was also evaluated by PCR amplification analysis of $\beta$-globin gene fragments (989-bp). The results were as follows: 1. Concentration of genomic DNA extracted from saliva was lower than that from blood (p<0.05), but there were no significant differences among various types of saliva samples. Purities of genomic DNA extracted from stimulated whole saliva and lyophilized one were significantly higher than that from blood (p<0.05). Purity of genomic DNA extracted from buccal swab was lower than those from various types of saliva samples (p<0.05). 2. Concentration of genomic DNA from saliva stored at room temperature showed gradual reduction after 1 month, and decreased significantly in 3 and 5 months (p<0.05, p<0.01, respectively). Purities of DNA from saliva stored for 3 and 5 months showed significant differences with those of fresh saliva and stored saliva for 1 month (p<0.05). 3. In the case of saliva stored at $4^{\circ}C$ and $-20^{\circ}C$, there were no significant changes of concentration of genomic DNA in 3 months. Concentration of DNA decreased significantly in 5 months (p<0.05). 4. There were no significant differences of concentration of genomic DNA from saliva stored at $-70^{\circ}C$ and from lyophilized one according to storage period. Concentration of DNA showed decreasing tendency in 5 months. 5. Concentration of genomic DNA immediately extracted from saliva dried on Petri dish were 60% compared with that of fresh saliva. Concentration of DNA from saliva stored at room temperature after dry-out showed rapid reduction within 2 weeks (p<0.05). 6. Amplification of $\beta$-globin gene using PCR was successful in all lyophilized saliva stored for 5 months. At the time of 1 month, $\beta$-globin gene was successfully amplified in all saliva samples stored at $-20^{\circ}C$ and $-70^{\circ}C$, and in some saliva samples stored at $4^{\circ}C$. $\beta$-globin gene was failed to amplify in saliva stored at room temperature and dry-out saliva.

The Effects of Self-regulatory Resources and Construal Levels on the Choices of Zero-cost Products (자아조절자원 및 해석수준이 공짜대안 선택에 미치는 영향)

  • Lee, Jinyong;Im, Seoung Ah
    • Asia Marketing Journal
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    • v.13 no.4
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    • pp.55-76
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    • 2012
  • Most people prefer to choose zero-cost products they may get without paying any money. The 'zero-cost effect' can be explained with a 'zero-cost model' where consumers attach special values to zero-cost products in a different way from general economic models (Shampanier, Mazar and Ariely 2007). If 2 different products at the regular prices of ₩200 and ₩400 simultaneously offer ₩200 discounts, the prices will be changed to ₩0 and ₩200, respectively. In spite of the same price gap of the two products after the ₩200 discounts, people are much more likely to select the free alternative than the same product at the price of ₩200. Although prior studies have focused on the 'zero-cost effect' in isolation of other factors, this study investigates the moderating effects of a self-regulatory resource and a construal level on the selection of free products. Self-regulatory resources induce people to control or regulate their behavior. However, since self-regulatory resources are limited, they are to be easily depleted when exerted (Muraven, Tice, and Baumeister 1998). Without the resources, consumers tend to become less sensitive to price changes and to spend money more extravagantly (Vohs and Faber 2007). Under this condition, they are also likely to invest less effort on their information processing and to make more intuitive decisions (Pocheptsova, Amir, Dhar, and Baumeister 2009). Therefore, context effects such as price changes and zero cost effects are less likely in the circumstances of resource depletion. In addition, construal levels have profound effects on the ways of information processing (Trope and Liberman 2003, 2010). In a high construal level, people tend to attune their minds to core features and desirability aspects, whereas, in a low construal level, they are more likely to process information based on secondary features and feasibility aspects (Khan, Zhu, and Kalra 2010). A perceived value of a product is more related to desirability whereas a zero cost or a price level is more associated with feasibility. Thus, context effects or reliance on feasibility (for instance, the zero cost effect) will be diminished in a high level construal while those effects may remain in a low level construal. When people make decisions, these 2 factors can influence the magnitude of the 'zero-cost effect'. This study ran two experiments to investigate the effects of self-regulatory resources and construal levels on the selection of a free product. Kisses and Ferrero-Rocher, which were adopted in the prior study (Shampanier et al. 2007) were also used as alternatives in Experiments 1 and 2. We designed Experiment 1 in order to test whether self-regulatory resource depletion will moderate the zero-cost effect. The level of self-regulatory resources was manipulated with two different tasks, a Sudoku task in the depletion condition and a task of drawing diagrams in the non-depletion condition. Upon completion of the manipulation task, subjects were randomly assigned to one of a decision set with a zero-cost option (i.e., Kisses ₩0, and Ferrero-Rocher ₩200) or a set without a zero-cost option (i.e., Kisses ₩200, and Ferrero-Rocher ₩400). A pair of alternatives in the two decision sets have the same price gap of ₩200 between a low-priced Kisses and a high-priced Ferrero-Rocher. Subjects in the no-depletion condition selected Kisses more often (71.88%) over Ferrero-Rocher when Kisses was free than when it was priced at ₩200 (34.88%). However, the zero-cost effect disappeared when people do not have self-regulatory resources. Experiment 2 was conducted to investigate whether constual levels influence the magnitude of the 'zero-cost effect'. To manipulate construal levels, 4 different 'why (in the high construal level condition)' or 'how (in the low construal level condition)' questions about health management were asked. They were presented with 4 boxes connected with downward arrows. In a box at the top, there was one question, 'Why do I maintain good physical health?' or 'How do I maintain good physical health?' Subjects inserted a response to the question of why or how they would maintain good physical health. Similar tasks were repeated for the 2nd, 3rd, and 4th responses. After the manipulation task, subjects were randomly assigned either to a decision set with a zero-cost option, or to a set without it, as in Experiment 1. When a low construal level is primed with 'how', subjects chose free Kisses (60.66%) more often over Ferrero-Rocher than they chose ₩200 Kisses (42.19%) over ₩400 FerreroRocher. On contrast, the zero-cost effect could not be observed any longer when a high construal level is primed with 'why'.

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A study on the Greeting's Types of Ganchal in Joseon Dynasty (간찰(簡札)의 안부인사(安否人事)에 대한 유형(類型) 연구(硏究))

  • Jeon, Byeong-yong
    • (The)Study of the Eastern Classic
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    • no.57
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    • pp.467-505
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    • 2014
  • I am working on a series of Korean linguistic studies targeting Ganchal(old typed letters in Korea) for many years and this study is for the typology of the [Safety Expression] as the part. For this purpose, [Safety Expression] were divided into a formal types and semantic types, targeting the Chinese Ganchal and Hangul Ganchal of modern Korean Language time(16th century-19th century). Formal types can be divided based on whether Normal position or not, whether Omission or not, whether the Sending letter or not, whether the relationship of the high and the low or not. Normal position form and completion were made the first type which reveal well the typicality of the [Safety Expression]. Original position while [Own Safety] omitted as the second type, while Original position while [Opposite Safety] omitted as the third type, Original position while [Safety Expression] omitted as the fourth type. Inversion type were made as the fifth type which is the most severe solecism in [Safety Expression]. The first type is refers to Original position type that [Opposite Safety] precede the [Own Safety] and the completion type that is full of semantic element. This type can be referred to most typical and normative in that it equipped all components of [Safety Expression]. A second type is that [Safety Expression] is composed of only the [Opposite Safety]. This type is inferior to the first type in terms of set pattern, it is never outdone when it comes to the appearance frequency. Because asking [Opposite Safety] faithfully, omitting [Own Safety] dose not greatly deviate politeness and easy to write Ganchal, it is utilized. The third type is the Original position type showing the configuration of the [Opposite Safety]+Own Safety], but [Opposite Safety] is omitted. The fourth type is a Original position type showing configuration of the [Opposite Safety+Own Safety], but [Safety Expression] is omitted. This type is divided into A ; [Safety Expression] is entirely omitted and B ; such as 'saving trouble', the conventional expression, replace [Safety Expression]. The fifth type is inversion type that shown to structure of the [Own Safety+Opposite Safety], unlike the Original position type. This type is the most severe solecism type and real example is very rare. It is because let leading [Own Safety] and ask later [Opposite Safety] for face save is offend against common decency. In addition, it can be divided into the direct type that [Opposite Safety] and [Own Safety] is directly connected and indirect type that separate into the [story]. The semantic types of [Safety Expression] can be classified based on whether Sending letter or not, fast or slow, whether intimate or not, and isolation or not. For Sending letter, [Safety Expression] consists [Opposite Safety(Climate+Inquiry after health+Mental state)+Own safety(status+Inquiry after health+Mental state)]. At [Opposite safety], [Climate] could be subdivided as [Season] information and [Climate(weather)] information. Also, [Mental state] is divided as receiver's [Family Safety Mental state] and [Individual Safety Mental state]. In [Own Safety], [Status] is divided as receiver's traditional situation; [Recent condition] and receiver's ongoing situation; [Present condition]. [Inquiry after health] is also subdivided as receiver's [Family Safety] and [Individual Safety], [Safety] is as [Family Safety] and [Individual Safety]. Likewise, [Inquiry after health] or [Safety] is usually used as pairs, in dimension of [Family] and [Individual]. This phenomenon seems to have occurred from a big family system, which is defined as taking care of one's parents or grand parents. As for the Written Reply, [Safety Expression] consists [Opposite Safety (Reception+Inquiry after health+Mental state)+Own safety(status+Inquiry after health+Mental state)], and only in [Opposite safety], a difference in semantic structure happens with Sending letter. In [Opposite Safety], [Reception] is divided as [Letter] which is Ganchal that is directly received and [Message], which is news that is received indirectly from people. [Safety] is as [Family Safety] and [Individual Safety], [Mental state] also as [Family Safety Mental state] and [Individual Safety Mental state].

Ecological Changes of Insect-damaged Pinus densiflora Stands in the Southern Temperate Forest Zone of Korea (I) (솔잎혹파리 피해적송림(被害赤松林)의 생태학적(生態学的) 연구(研究) (I))

  • Yim, Kyong Bin;Lee, Kyong Jae;Kim, Yong Shik
    • Journal of Korean Society of Forest Science
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    • v.52 no.1
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    • pp.58-71
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    • 1981
  • Thecodiplosis japonesis is sweeping the Pinus densiflora forests from south-west to north-east direction, destroying almost all the aged large trees as well as even the young ones. The front line of infestation is moving slowly but ceaselessly norhwards as a long bottle front. Estimation is that more than 40 percent of the area of P. densiflora forest has been damaged already, however some individuals could escapes from the damage and contribute to restore the site to the previous vegetation composition. When the stands were attacked by this insect, the drastic openings of the upper story of tree canopy formed by exclusively P. densiflora are usually resulted and some environmental factors such as light, temperature, litter accumulation, soil moisture and offers were naturally modified. With these changes after insect invasion, as the time passes, phytosociologic changes of the vegetation are gradually proceeding. If we select the forest according to four categories concerning the history of the insect outbreak, namely, non-attacked (healthy forest), recently damaged (the outbreak occured about 1-2 years ago), severely damaged (occured 5-6 years ago), damage prolonged (occured 10 years ago) and restored (occured about 20 years ago), any directional changes of vegetation composition could be traced these in line with four progressive stages. To elucidate these changes, three survey districts; (1) "Gongju" where the damage was severe and it was outbroken in 1977, (2) "Buyeo" where damage prolonged and (3) "Gochang" as restored, were set, (See Tab. 1). All these were located in the south temperate forest zone which was delimited mainly due to the temporature factor and generally accepted without any opposition at present. In view of temperature, the amount and distribution of precipitation and various soil factor, the overall homogeneity of environmental conditions between survey districts might be accepted. However this did not mean that small changes of edaphic and topographic conditions and microclimates can induce any alteration of vegetation patterns. Again four survey plots were set in each district and inter plot distance was 3 to 4 km. And again four subplots were set within a survey plot. The size of a subplot was $10m{\times}10m$ for woody vegetation and $5m{\times}5m$ for ground cover vegetation which was less than 2 m high. The nested quadrat method was adopted. In sampling survey plots, the followings were taken into account: (1) Natural growth having more than 80 percent of crown density of upper canopy and more than 5 hectares of area. (2) Was not affected by both natural and artificial disturbances such as fire and thinning operation for the past three decades. (3) Lower than 500 m of altitude (4) Less than 20 degrees of slope, and (5) Northerly sited aspect. An intensive vegetation survey was undertaken during the summer of 1980. The vegetation was devided into 3 categories for sampling; the upper layer (dominated mainly by the pine trees), the middle layer composed by oak species and other broad-leaved trees as well as the pine, and the ground layer or the lower layer (shrubby form of woody plants). In this study our survey was concentrated on woody species only. For the vegetation analysis, calculated were values of intensity, frequency, covers, relative importance, species diversity, dominance and similarity and dissimilasity index when importance values were calculated, different relative weights as score were arbitrarily given to each layer, i.e., 3 points for the upper layer, 2 for the middle layer and 1 for the ground layer. Then the formula becomes as follows; $$R.I.V.=\frac{3(IV\;upper\;L.)+2(IV.\;middle\;L.)+1(IV.\;ground\;L.)}{6}$$ The values of Similarity Index were calculated on the basis of the Relative Importance Value of trees (sum of relative density, frequency and cover). The formula used is; $$S.I.=\frac{2C}{S_1+S_2}{\times}100=\frac{2C}{100+100}{\times}100=C(%)$$ Where: C = The sum of the lower of the two quantitative values for species shared by the two communities. $S_1$ = The sum of all values for the first community. $S_2$ = The sum of all values for the second community. In Tab. 3, the species composition of each plot by layer and by district is presented. Without exception, the species formed the upper layer of stands was Pinus densiflora. As seen from the table, the relative cover (%), density (number of tree per $500m^2$), the range of height and diameter at brest height and cone bearing tendency were given. For the middle layer, Quercus spp. (Q. aliena, serrata, mongolica, accutissina and variabilis) and Pinus densiflora were dominating ones. Genus Rhodedendron and Lespedeza were abundant in ground vegetation, but some oaks were involved also. (1) Gongju district The total of woody species appeared in this district was 26 and relative importance value of Pinus densiflora for the upper layer was 79.1%, but in the middle layer, the R.I.V. for Quercus acctissima, Pinus densiflora, and Quercus aliena, were 22.8%, 18.7% and 10.0%, respectively, and in ground vegetation Q. mongolica 17.0%, Q. serrata 16.8% Corylus heterophylla 11.8%, and Q. dentata 11.3% in order. (2) Buyeo district. The number of species enumerated in this district was 36 and the R.I.V. of Pinus densiflora for the uppper layer was 100%. In the middle layer, the R.I.V. of Q. variabilis and Q. serrata were 8.6% and 8.5% respectively. In the ground vegetative 24 species were counted which had no more than 5% of R.I.V. The mean R.I.V. of P.densiflora ( totaling three layers ) and averaging four plots was 57.7% in contrast to 46.9% for Gongju district. (3) Gochang-district The total number of woody species was 23 and the mean R.I.V. of Pinus densiflora was 66.0% showing greater value than those for two former districts. The next high value was 6.5% for Q. serrata. As the time passes since insect outbreak, the mean R.I.V. of P. densiflora increased as the following order, 46.9%, 57.7% and 66%. This implies that P. densiflora was getting back to its original dominat state again. The pooled importance of Genus Quercus was decreasing with the increase of that for Pinus densiflora. This trend was contradict to the facts which were surveyed at Kyonggi-do area (the central temperate forest zone) reported previously (Yim et al, 1980). Among Genus Quercus, Quercus acutissina, warm-loving species, was more abundant in the southern temperature zone to which the present research is concerned than the central temperate zone. But vice-versa was true with Q. mongolica, a cold-loving one. The species which are not common between the present survey and the previous report are Corpinus cordata, Beltala davurica, Wisturia floribunda, Weigela subsessilis, Gleditsia japonica var. koraiensis, Acer pseudosieboldianum, Euonymus japonica var. macrophylla, Ribes mandshuricum, Pyrus calleryana var. faruiei, Tilia amurensis and Pyrus pyrifolia. In Figure 4 and Table 5, Maximum species diversity (maximum H'), Species diversity (H') and Eveness (J') were presented. The Similarity indices between districts were shown in Tab. 5. Seeing Fig. 6, showing two-dimensional ordination of polts on the basis of X and Y coordinates, Ai plots aggregate at the left site, Bi plots at lower site, and Ci plots at upper-right site. The increasing and decreasing patterns as to Relative Density and Relative Importance Value by genus or species were given in Fig. 7. Some of the patterns presented here are not consistent with the previously reported ones (Yim, et al, 1980). The present authors would like to attribute this fact that two distinct types of the insect attack, one is the short war type occuring in the south temperate forest zone, which means that insect attack went for a few years only, the other one is a long-drawn was type observed at the temperate forest zone in which the insect damage went on continuously for several years. These different behaviours of infestation might have resulted the different ways of vegetational change. Analysing the similarity indices between districts, the very convincing results come out that the value of dissimilarity index between A and B was 30%, 27% between B and C and 35% between A and C (Table 6). The range of similarity index was obtained from the calculation of every possible combinations of plots between two districts. Longer time isolation between communities has brought the higher value of dissimilarity index. The main components of ground vegetation, 10 to 20 years after insect outbreak, become to be consisted of mainly Genus Lespedeza and Rhododendron. Genus Quercus which relate to the top dorminant state for a while after insect attack was giving its place to Pinus densiflora. It was implied that, provided that the soil fertility, soil moisture and soil depth were good enough, Genus Quercuss had never been so easily taken ever by the resistant speeies like Pinus densiflora which forms the edaphic climax at vast areas of forest land. Usually they refer Quercus to the representative component of the undisturbed natural forest in the central part of this country.

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Studies on the Internal Changes and Germinability during the Period of Seed Maturation of Pinus koraiensis Sieb. et Zucc. (잣나무 종자(種字) 성숙과정(成熟過程)에 있어서의 내적변화(內的變化)와 발아력(發芽力)에 대(對)한 연구(硏究))

  • Min, Kyung-Hyun
    • Journal of Korean Society of Forest Science
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    • v.21 no.1
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    • pp.1-34
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    • 1974
  • The author intended to investigate external and internal changes in the cone structure, changes in water content, sugar, fat and protein during the period of seed maturation which bears a proper germinability. The experimental results can be summarized as in the following. 1. Male flowers 1) Pollen-mother cells occur as a mass from late in April to early in May, and form pollen tetrads through meiosis early and middle of May. Pollen with simple nucleus reach maturity late in May. 2) Stamen number of a male flower is almost same as the scale number of cone and is 69-102 stamens. One stamen includes 5800-7300 pollen. 3) The shape is round and elliptical, both of a pollen has air-sac with $80-91{\mu}$ in length, and has cuticlar exine and cellulose intine. 4) Pollen germinate in 68 hours at $25^{\circ}C$ with distilled water of pH 6.0, 2% sugar and 0.8% agar. 2. Female flowers 1) Ovuliferous scales grow rapidly in late April, and differentiation of ovules begins early in May. Embryo-sac-mother cells produce pollen tetrads through meiosis in the middle of May, and flower in late May. 2) The pollinated female flowers show repeated divisions of embryo-sac nucleus, and a great number of free nuclei form a mass for overwintering. Morphogenesis of isolation in the mass structure takes place from the middle of March, and that forms albuminous bodies of aivealus in early May. 3. Formation of pollinators and embryos. 1) Archegonia produce archegonial initial cells in the middle and late April, and pollinators are produced in the late April and late in early May. 2) After pollination, Oespore nuclei are seen to divide in the late May forming a layer of suspensor from the diaphragm in early June and in the middle of June. Thus this happens to show 4 pro-embryos. The organ of embryos begins to differentiate 1 pro-embryo and reachs perfect maturation in late August. 4. The growth of cones 1) In the year of flowering, strobiles grow during the period from the middle of June to the middle of July, and do not grow after the middle of August. Strobiles grow 1.6 times more in length 3.3 times short in diameter and about 22 times more weight than those of female flower in the year of flowering. 2) The cones at the adult stage grow 7 times longer in diameter, 12-15 times shorter diameter than those of strobiles after flowering. 3) Cone has 96-133 scales with the ratio of scale to be 69-80% and the length of cone is 11-13cm. Diameter is 5-8cm with 160-190g weight, and the seed number of it is 90-150 having empty seed ratio of 8-15%. 5. Formation of seed-coats 1) The layers of outer seed-coat become most for the width of $703{\mu}$ in the middle of July. At the adult stage of seed, it becomes $550-580{\mu}$ in size by decreasing moisture content. Then a horny and the cortical tissue of outer coats become differentiated. 2) The outer seed-coat of mature seeds forms epidermal cells of 3-4 layers and the stone cells of 16-21 layers. The interior part of it becomes parenchyma layer of 1 or 2 rows. 3) Inner seed-coat is formed 2 months earlier than the outer seed-coat in the middle of May, having the most width of inner seed-coat $667{\mu}$. At the adult stage it loses to $80-90{\mu}$. 6. Change in moisture content After pollination moisture content becomes gradually increased at the top in the early June and becomes markedly decreased in the middle of August. At the adult stage it shows 43~48% in cone, 23~25% in the outer seed-coat, 32~37% in the inner seed-coat, 23~26% in the inner seed-coat and endosperm and embryo, 21~24% in the embryo and endosperm, 36~40% in the embryos. 7. The content compositions of seed 1) Fat contents become gradually increased after the early May, at the adult stage it occupies 65~85% more fat than walnut and palm. Embryo includes 78.8% fat, and 57.0% fat in endosperm. 2) Sugar content after pollination becomes greatly increased as in the case of reducing sugar, while non-reducing sugar becomes increased in the early June. 3) Crude protein content becomes gradually increased after the early May, and at the adult stage it becomes 48.8%. Endosperm is made up with more protein than embryo. 8. The test of germination The collected optimum period of Pinus koraiensis seeds at an adequate maturity was collected in the early September, and used for the germination test of reduction-method and embryo culture. Seeds were taken at the interval of 7 days from the middle of July to the middle of September for the germination test at germination apparatus.

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