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Ginseng anthracnose in Korea Factors affecting primary inoculum, growth of the pathogen, disease development and control (인삼${\cdot}$탄저병에 관한 연구 전염원, 병원균의 생태, 발병요인 및 방제)

  • Chung Hoo-Sup;Bae Hyo-Won
    • Korean journal of applied entomology
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    • v.18 no.1 s.38
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    • pp.35-41
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    • 1979
  • Four to $17\%$ of the seeds of ginseng (Panax ginseng Meyer) collected from seemingly healthy plants carried Colletotrichum panacicola Nakata et Takimoto whereas the seeds from the plants with anthracnose sympotoms carried $42\%$ of the same fungus. Prevalent organisms isolated other than C. panacicola from seeds of both kinds of plants were Fusarium, Alternaria, Phoma, Trichoderma and others, ana in that order on acidified potato sucrose agar. C. panacicola also was isolated from 18 months old herbarium specimens. The fungus in the infected tissues also survived during the Korean winter months either on the soil surface or in the soil at 10 and 30 em in depth. When conidial suspensions of C. panacicola were inoculated on detached ginseng leaves, anthracnose symptoms occurred from 25 to $35^{\circ}C$. No symptoms occurred at temperatures below $17^{\circ}C$. Direct sunlight increased significantly the number of anthracnose lesions over those obtained in leaves inoculated in darkness or in 400 lux of fluorescent light. The lesions decreased as age of the leaves increased or as the number of conidia applied decreased. Optimum temperature for mycelial growth and conidial formation of C. panacicola was $25^{\circ}C$. Optimum pH for the mycelial growth was at $pH\;2.8\~4.6$ while the most conidial formation occurred at $pH\;5.2\~5.8.$. When fungicides were applied in the field to ginseng plants with a conidial suspension of C. panacicola, the most effective control of the anthracnose disease was by spraying with difolatan, and followed by maneb, zineb, captan and phaltan; Bordeaux mixture and ferbam were significantly less effective but significantly better than the inoculated control plants.

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A STUDY ON THE REMOVAL TORQUE OF TITANIUM IMPLANTS (Titanium Implant의 Removal Torque에 관한 연구)

  • Lee, June-Seok;Kim, Yung-Soo;Kim, Chang-Whe
    • The Journal of Korean Academy of Prosthodontics
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    • v.32 no.1
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    • pp.148-169
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    • 1994
  • The concept of biologic attachment of load-bearing implants has developed over the past decades as an alternative to the difficulties associated with long term implantation using mechanical fixation and bone cement. The choice of implant material is also as critical an element as site preparation or insertion procedure. The properties of implants that affect host tissue responses are not limited to chemical composition alone, but also include shape, surface characteristics, site of implantation, and mechanical interaction with host tissues. Initial mechanical interlocking prevents micromotion and may be a prerequisite for direct bone apposition. A hard tightening of screws does not necessarily mean a stronger fixation and final tightening of the fixtures is dependent on the experience of the operator. Removal torque is lower than insertion torque. The purpose of this study was to investigate differences in the removal torques at the bone-implant interface of polished and sandblasted Titanium. This experiment will give insight into important factors that must be considered when interpreting in vivo screwing forces on implants during the connection of the transmucosal abutments. We evaluated the significance of different surface textures by comparison of the withdrawal forces necessary for removal of otherwise identical rough and polished implants of Titanium and also evaluated interfacial response on the light microscopic level to implant surface. And the priority of the area of insertion on osseointegration were evaluated. 9 Titanium implants - among them, 3 were for the developmental - of either a smooth or rough surface finish were inserted in the dog mandible in the right side. 3 months later Kanon Torque Gauge was used to unscrew the implants. The results were as follows : 1. No significant difference was seen in the removal torque due to variation in surface treatment, 23 Ncm for the sandblasted and 23.33 Ncm for the polished surface (p>0.05). 2. Implants in the anterior (25 Ncm) mandible showed better resistance to unscrewing in comparison to ones in the posterior (18 Ncm) region (p<0.05). 3. Developmental fixtures (22 Ncm) had similar pullout strength to the control group (p>0.05).

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Effects of Different Nitrogen Solution Varying Concentration on Seed Germination of Vegetable Crops(Brassica rapa L., Lactuca sativa L.) (농도(濃度)가 다른 여러가지 질소원(窒素源) 양분용액(養分溶液)이 배추와 상치 종자발아(種子發芽)에 미치는 영향(影響))

  • Hong, Soon-Dal;Lee, Yun-Hwan
    • Korean Journal of Soil Science and Fertilizer
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    • v.25 no.1
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    • pp.57-61
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    • 1992
  • For testing salts effect on seed germination, nitrogen solutions($(NH_4)_2SO_4$, $NH_4NO_3$, $KNO_3$, $Mg(NO_3)_2$, $Ca(NO_3)_2$, $(NH_2)_2CO$) were treated to chinese cabbage(Brassica rape L.) and lettuce(Lactuca sativa L.) seeding on the quartz sand bed given a tilt to wet by dripping. Electrical conductivities (mS/cm) increased with direct proportion by equivalent gram-molecular weight at $(NH_4)_2SO_4$ and $KNO_3$, $NH_4NO_3$, but those of Mg and Ca salt remained 1 1/2 times higher. And urea solution never showed EC at all. $(NH_4)_2SO_4$ solution appeared to have value of EC with 1.37 times as high as that of $KNO_3$ and it was in order of $(NH_4)_2SO_4>NH_4NO_3>KNO_3>Ca(NO_3)_2>Mg(NO_3)_2$ comparing with same percentage solution. Application of $Mg(NO_3)_2$ and $(NH_4)_2SO_4$ among 6 salts resulted in a severe decreas in germination of both crops, and $NH_4NO_3$ showed light inhibition in comparison to $KNO_3$. Urea showed little effect on germination as the same as $Ca(NO_3)_2$ and $KNO_3$ solution at low concentrations, but the latter two salts reduced germination remarkably at high concentrations. It is likely to show that germination inhibition is not affected by salt salanity but by the sort of salts.

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Community Orchestra Educational Activities and Development of Poor Children (지역사회 오케스트라 교육 활동과 빈곤아동 발달)

  • An, Eunmi
    • Korean Journal of Social Welfare
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    • v.68 no.1
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    • pp.225-248
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    • 2016
  • This study explores the effects on development of poor children by community-based orchestra educational activities and the orchestra educational activities factors for promoting the effects using longitudinal data are those collected for "The Evaluation of the Impact of Our Neighborhood Orchestra on Children's Learning" made by the Seoul Philharmonic Orchestra. For these purposes, this study employed a latent growth model analysis of the factors such as depression, aggressive behavior, communality and interpersonal relationship of development of poor children and evaluation, satisfaction, outsiders'attention and participation of facilitative factors. The result shows that they displayed significantly positive development in depression, aggressive behavior, and interpersonal relationship. It appears that the evaluation on music achievement had a positive impact on the rate of change in communality, while the evaluation on attitude had an impact in the initial value of depression, aggressive behavior, and communality, also the sense of satisfaction had a positive impact on the initial value of communality and interpersonal relationship in conditional models. And parents' attention and participation had a negative impact on the initial value of aggressive behavior, while the attention and participation of the community showed a positive impact on the initial value of depression and aggressive behavior. Based on these results, this study attempted to broaden the understanding of the development of poor children taking part in orchestra-based educational activities and provide a practical basis for social workers' direct invention, and look for new ways by shedding light on the merits of the cultural/art education of poor children that engage in the community-based orchestra educational activities.

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A STUDY ON SHEAR BOND STRENGTH OF INTERFACE BETWEEN BONE AND TITANIUM PLASMA SPRAYED IMZ IMPLANT IN RABBITS (가토에 이식된 Titanium plasma Sprayed IMZ 임프란트와 골의 계면 접촉 양상에 따른 결합력에 관한 연구)

  • Han, Chong-Hyun;Han, Dong-Hoo
    • The Journal of Korean Academy of Prosthodontics
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    • v.29 no.2
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    • pp.225-243
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    • 1991
  • In recent years immediate implantation has been tried by a few clinicians. This study placed IMZ implants in the rabbit femur with and without bony defects around the implant for simulating fresh extraction site. And one group with bony defects used porous hydroxyapatite ganules(HA) to fill if and the other group left the bony defects around the implant. The purpose of this study was to compare the shear bond strength and the bony contact and formation around the implant. Fifteen rabbits were divided into three groups and placed 10 IMZ implants to each group. Implant sites were surgically prepared with IMZ drills kit and implants were placed(Control), artificial bony defect was created with Apaceram drills kit around the implant sites and implants were placed(Experimental I), bony defect was filled with porous hydroxyapatite granules(Experimental II). Thereafter, rabbits were sacrificed at 8th week and specimens were prepared and pushout tested for shear bond strength of bone-implant interface immediately. Undecalcified and decalcified specimens were prepared with Vilanueva and hematoxylin-eosin stain for light microscopic finding. The results of this study were as follows. 1. In the control group, mean shear strength of bone-implant interface was $2.614{\pm}0.680$ MPa, experimental I was $0.664{\pm}0.322$ MPa, and experimental II was $2.281{\pm}0.606$ MPa. There was significant difference between control and experimental I, between experimental I and experimental II, but did not show significant difference between control and experimental II statistically. 2. In the bony formation surrounding IMZ implant of the three groups, that of cortical bone is more advanced than cancellous bone area. 3. In the histological findings of undecalcified specimens, control and experimental II showed more than 50% of bony or osteoid formation at the bony-implant interface. 4. In the histological findings of undecalcified specimens, experimental I showed less than 50% of bony or osteoid formation at the interface, and observed partial bony defect in the coronal zone. 5. In the experimental II group, were observed direct bony contact to hydroxyapatite granules, and infiltration of a few giant cells. 6. No inflammatory responses were seen around the titanium implants and the hydroxyapatite granules.

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ORTHODONTIC TRACTION OF IMPACTED POSTERIOR TEETH : CASE REPORTS (매복 구치부 치아의 교정적 이동 : 증례 보고)

  • Maeng, Yu-Jin;Oh, So-Hee
    • Journal of the korean academy of Pediatric Dentistry
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    • v.36 no.4
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    • pp.613-618
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    • 2009
  • Impacted molars are not usual with the prevalence rate of less than 1%, however problems such as infraocclusion, extrusion of the opposite tooth and lack of space are caused. If molars are impacted, radiographic check-up and observations are needed as they play an important role in skeletal development and mastication. Causes of impaction are underdevelopment of roots, supernumerary teeth, cysts, odontomas, ankylosis and etc. In our first case, we present impacted molar which was surgically exposed and orthodontically traded. As the developmental state of the root was less than half at first visit, we observed until the root was 2/3 in its length and traction was carried out. The second case is orthodontic traded molar with compleate enucleation of the existing cysts. When trading impacted molars, direct bonding of attachments to the tooth and light continuous forces are recommended so as to ankylosis, external absorption and periodontal attachment loss avoid. Fixed appliances tract the teeth on arch and obtain eruption spaces without patient's cooperation. We report surgically exposed and orthodontically traded molars which resulted in good occlusion and patients satisfaction.

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CYP2E1 Genetic Polymorphism with Dietary, Tobacco, Alcohol Habits, H. pylori Infection Status and Susceptibility to Stomach Cancer in Mizoram, India

  • Malakar, Mridul;Devi, K. Rekha;Phukan, Rup Kumar;Kaur, Tanvir;Deka, Manab;Puia, Lalhriat;Baruah, Debajit;Mahanta, Jagadish;Narain, Kanwar
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.20
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    • pp.8815-8822
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    • 2014
  • Background: The incidence of stomach cancer in India is highest in the state of Mizoram. In this population based matched case-control study, we evaluated the relationship between CYP450 2E1 RsaI polymorphism and risk of stomach cancer taking into considering various important dietary habits along with tobacco, alcohol consumption and H. pylori infection status. Materials and Methods: A total of 105 histologically confirmed stomach cancer cases and 210 matched healthy population controls were recruited. CYP2E1 RsaI genotypes were determined by PCR-RFLP and H. pylori infection status by ELISA. Information on various dietary, tobacco and alcohol habits was recorded in a standard questionnaire. Results: Our study revealed no significant association between the CYP2E1 RsaI polymorphism and overall risk of stomach cancer in Mizoram. However, we observed a non-significant protective effect of the variant allele (A) of CYP2E1 against stomach cancer. Tobacco smokers carrying C/C genotype have three times more risk of stomach cancer, as compared to non-smokers carrying C/C genotype. Both Meiziol and cigarette current and past smokers who smoked for more than 10 times per day and carrying the (C/C) genotype are more prone to develop stomach cancer. Smoke dried fish and preserved meat (smoked/sun dried) consumers carrying C/C genotype possesses higher risk of stomach cancer. No significant association between H. pylori infection and CYP2E1 RsaI polymorphism in terms of stomach cancer was observed. Conclusions: Although no direct association between the CYP2E1 RsaI polymorphism and stomach cancer was observed, relations with different tobacco and dietary risk habits in terms of developing stomach cancer exist in this high risk population of north-eastern part of India. Further in-depth study recruiting larger population is required to shed more light on this important problem.

An Investigation on Gridline Edges in Screen-Printed Crystalline Silicon Solar Cells

  • Kim, Seongtak;Park, Sungeun;Kim, Young Do;Kim, Hyunho;Bae, Soohyun;Park, Hyomin;Lee, Hae-Seok;Kim, Donghwan
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.490.2-490.2
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    • 2014
  • Since the general solar cells accept sun light at the front side, excluding the electrode area, electrons move from the emitter to the front electrode and start to collect at the grid edge. Thus the edge of gridline can be important for electrical properties of screen-printed silicon solar cells. In this study, the improvement of electrical properties in screen-printed crystalline silicon solar cells by contact treatment of grid edge was investigated. The samples with $60{\Omega}/{\square}$ and $70{\Omega}/{\square}$ emitter were prepared. After front side of samples was deposited by SiNx commercial Ag paste and Al paste were printed at front side and rear side respectively. Each sample was co-fired between $670^{\circ}C$ and $780^{\circ}C$ in the rapid thermal processing (RTP). After the firing process, the cells were dipped in 2.5% hydrofluoric acid (HF) at room temperature for various times under 60 seconds and then rinsed in deionized water. (This is called "contact treatment") After dipping in HF for a certain period, the samples from each firing condition were compared by measurement. Cell performances were measured by Suns-Voc, solar simulator, the transfer length method and a field emission scanning electron microscope. According to HF treatment, once the thin glass layer at the grid edge was etched, the current transport was changed from tunneling via Ag colloids in the glass layer to direct transport via Ag colloids between the Ag bulk and the emitter. Thus, the transfer length as well as the specific contact resistance decreased. For more details a model of the current path was proposed to explain the effect of HF treatment at the edge of the Ag grid. It is expected that HF treatment may help to improve the contact of high sheet-resistance emitter as well as the contact of a high specific contact resistance.

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Studies on the Effects of the Pine Needle Gall Midge, Thecodiplosis japonensis Uchida et Inouye, on the Growth of the Red Pine, Pinus densiflora S. et Z.(III) -Radial Growth Impact- (솔잎혹파리가 소나무생장(生長)에 미치는 영향(影響)에 관(關)한 연구(硏究)(III) -직경생장저해(直徑生長沮害)-)

  • Park, Ki Nam;Hyun, Jai Sun
    • Journal of Korean Society of Forest Science
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    • v.65 no.1
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    • pp.48-53
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    • 1984
  • Using the Duff and Noland's method, the annual ring growth patterns of the red pine in the natural stands were examined at two locations; Seocheon, Chungnam-do where the stand had been infested with the pine needle gall midge, Thecodiplosis japonensis, during the years from 1975 to 1978, and Hongsong, Chungnam-do where had been no incidence of the insect damage. The results obtained are as follows: 1) With the normal red pine of 13 year old, the growth pattern in the oblique sequence indicates that the annual growth rates are maximum at the few terminal internodes, and decrease gradually with the downward internodes. Such characteristic of the growth pattern is not clear in the horizontal sequence of annual rings. 2) The indications of the radial growth reduction of the pine tree due to the pine gall midge infestation could be examined with any of three series at the crown level internodes; horizontal, vertical and oblique series. For the basal internodes, however, the horizontal series appeared to be inadequate for the analysis of the damage impact because it seemed to be masked by various factors other than direct effects of the damage. 3) Of the three ways of radial growth analyses, oblique sequence seems to be the most usefull, especially for the detection of the impact on growth caused by incipient or light infestation.

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Rhythmic Control and Physiological Functional Significance of Melatonin Production in Circadian Rhythm (주기적 리듬 조절에 의한 멜라토닌 생산과 생리적 기능의 중요성)

  • Kim, Min Gyun;Park, Seul Ki;Ahn, Soon Cheol
    • Journal of Life Science
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    • v.23 no.8
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    • pp.1064-1072
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    • 2013
  • Circadian rhythm is controlled by hormonal oscillations governing the physiology of all living organisms. In mammals, the main function of the pineal gland is to transform the circadian rhythm generated in the hypothalamic suprachiasmatic nucleus into rhythmic signals of circulating melatonin characterized by a largely nocturnal increase that closely reflects the duration of night time. The pineal gland has lost direct photosensitivity, but responds to light via multi-synaptic pathways that include a subset of retinal ganglion cells. Rhythmic control is achieved through a tight coupling between environmental lighting and arylalkylamine-N-acetyltransferase (AANAT) expression, which is the rhythm-controlling enzyme in melatonin synthesis. Previous studies on the nocturnal expression of AANAT protein have described transcriptional, post-transcriptional, and post-translational regulatory mechanisms. Molecular mechanisms for dependent AANAT expression provide novel aspects for melatonin's circadian rhythmicity. Extensive animal research has linked pineal melatonin for the expression of seasonal rhythmicity in many mammalian species to the modulation of circadian rhythms and to sleep regulation. It has value in treating various circadian rhythm disorders, such as jet lag or shift-work sleep disorders. Melatonin, also, in a broad range of effects with a significant regulation influences many of the body's physiological functions. In addition, this hormone is known to influence reproductive, cardiovascular, and immunological regulation as well as psychiatric disorders.