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Analysis of U.S.-China Relations on The Korean Peninsula Military Puzzle : Under Circumstance of NK's Nuclear, THAAD, US-ROK Alliance (한반도 군사적 현안에 관한 미중관계 고찰 : 북핵, 사드, 한미동맹의 환경 하에서)

  • Woo, Jeongmin
    • Convergence Security Journal
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    • v.17 no.3
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    • pp.83-93
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    • 2017
  • The U.S.-China Relations could be analyzed two perspectives and their basis under major international p olitics theory-power transition with conditions: (1) North Korean's nuclear puzzle, (2) THAAD in the Kor ean Peninsula and (3) the U.S.-ROK Alliance. One perspective is the global order dominates the regional order, and then stable regional order comes out. The other is the regional order dominates the global ord er, and China wages a regional hegemonic conflict against the United States. Consequently, America's o verwhelming leadership in North Korean's nuclear, THAAD and U.S.-ROK Alliance as national power is expected to endure. But China also has expected empowerment and cooperation for the peace and stabilit y on the Korean Peninsula military problems. In this perspective, South Korea needs to pay attention to the changing power distribution and competition between the U.S. and China and needs to strengthen a balancing and harmonious diplomatic strategy, so called 'see-saw diplomacy'.

The Effect of Circulat Hole Size and Distribution on Strength of Braided Composite (브레이드 복합재료의 원공의 크기와 분포가 재료강도에 미치는 영향)

  • Lee, Gyeong-U;Gang, Tae-Jin
    • Korean Journal of Materials Research
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    • v.4 no.3
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    • pp.253-258
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    • 1994
  • The effect of hole size and hole-to-hole distance in the braided and laminated composite was studied in terms of tensile strength, pin bearing strength, and flexural strength of S2-glass fiber braided polyester. The tensile strength reduction with hole size was well fitted with he Whitney and Nuismer's prediction for the laminated composite. The characteristic distance was measured to be about 1.6mm for braided composite and 1.8mm for laminated one. The effect of distance between the centers of two circu lar holes on tensile strength was negligible when the distance between these two holes was larger than 4 times of the diameter of circular hole for both braided and laminated composite. The side effect was diminished when the center of hole was located 3 times farther than the diamet.er of the hole. The pin bearing strengths was decreased with the size of pin hole for both braided and laminated composite.

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How will surface treatments affect the translucency of porcelain laminate veneers?

  • Turgut, Sedanur;Bagis, Bora;Ayaz, Elif Aydogan;Korkmaz, Fatih Mehmet;Ulusoy, Kivanc Utku;Bagis, Yildirim Hakan
    • The Journal of Advanced Prosthodontics
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    • v.6 no.1
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    • pp.8-13
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    • 2014
  • PURPOSE. The purpose of this study was to evaluate whether surface treatments affect the translucency of laminate veneers with different shades and thicknesses. MATERIALS AND METHODS. A total of 224 disc-shaped ceramic veneers were prepared from A1, A3, HT (High Translucent) and HO (High Opaque) shades of IPS e.max Press (Ivoclar Vivadent) with 0.5 mm and 1.0 mm thicknesses. The ceramics were divided into four groups for surface treatments. Group C: no surface treatments; Group HF: etched with hydrofluoric acid; Group SB: sandblasted with 50-${\mu}m$ $Al_2O_3$; and Group L; irradiated with an Er;YAG laser. A translucent shade of resin cement (Rely X Veneer, 3M ESPE) was chosen for cementation. The color values of the veneers were measured with a colorimeter and translucency parameter (TP) values were calculated. A three-way ANOVA with interactions for TP values was performed and Bonferroni tests were used when appropriate (${\alpha}=0.05$). RESULTS. There were significant interactions between the surface treatments, ceramic shades and thicknesses (P=.001). For the 0.5-mm-thick specimens there were significant differences after the SB and L treatments. There was no significant difference between the HF and C treatments for any shades or thicknesses (P>.05). For the 1-mm-thick ceramics, there was only a significant difference between the L and C treatments for the HT shade ceramics (P=.01). There were also significant differences between the SB and C treatments except not for the HO shades (P=.768). CONCLUSION. The SB and L treatments caused laminate veneers to become more opaque; however, HF treatment did not affect the TP values. When the laminate veneers were thinner, both the shade of the ceramic and the SB and laser treatments had a greater effect on the TP values.

The effects of different surface treatments on the shear bond strengths of two dual-cure resin cements to CAD/CAM restorative materials

  • Turker, Nurullah;Buyukkaplan, Ulviye Sebnem;Basar, Ebru Kaya;Ozarslan, Mehmet Mustafa
    • The Journal of Advanced Prosthodontics
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    • v.12 no.4
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    • pp.189-196
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    • 2020
  • PURPOSE. The aim of the present study was to investigate the effects of surface treatments on the bond strengths between polymer-containing restorative materials and two dual-cure resin cements. MATERIALS AND METHODS. In the present study, rectangular samples prepared from Lava Ultimate (LU) and Vita Enamic (VE) blocks were used. The specimen surfaces were treated using CoJet sandblasting, 50 ㎛ Al2O3 sandblasting, % 9 HF (hydrofluoric) acid, ER,Cr:YSGG laser treatment, and Z-Prime. Dual-cure resin cements (TheraCem and 3M RelyX U 200) were applied on each specimen's treated surface. A micro-tensile device was used to evaluate shear bond strength. Statistical analysis was performed using the SAS 9.4v3. RESULTS. While the bond strength using TheraCem with LU or VE was not statistically significant (P=.164), the bond strength using U200 with VE was statistically significant (P=.006). In the TheraCem applied VE groups, Z-Prime and HF acid were statistically different from CoJet, Laser, and Sandblast groups. In comparison of TheraCem used LU group, there was a statistically significant difference between HF acid and other surface treatments. CONCLUSION. The bonding performance between the restorative materials and cements were material type-dependent and surface treatment had a large effect on the bond strength. Within the limitations of the study, the use of both U200 and TheraCem may be suggested if Z-prime was applied to intaglio surfaces of VE. The cementation of LU using TheraCem is suitable after HF acid conditioning of the restoration surfaces.

Physics study for high-performance and very-low-boron APR1400 core with 24-month cycle length

  • Do, Manseok;Nguyen, Xuan Ha;Jang, Seongdong;Kim, Yonghee
    • Nuclear Engineering and Technology
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    • v.52 no.5
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    • pp.869-877
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    • 2020
  • A 24-month Advanced Power Reactor 1400 (APR1400) core with a very-low-boron (VLB) concentration has been investigated for an inherently safe and high-performance PWR in this work. To develop a high-performance APR1400 which is able to do the passive frequency control operation, VLB feature is essential. In this paper, the centrally-shielded burnable absorber (CSBA) is utilized for an efficient VLB operation in the 24-month cycle APR1400 core. This innovative design of the VLB APR1400 core includes the optimization of burnable absorber and loading pattern as well as axial cutback for a 24-month cycle operation. In addition to CSBA, an Er-doped guide thimble is also introduced for partial management of the excess reactivity and local peaking factor. To improve the neutron economy of the core, two alternative radial reflectors are adopted in this study, which are SS-304 and ZrO2. The core reactivity and power distributions for a 2-batch equilibrium cycle are analyzed and compared for each reflector design. Numerical results show that a VLB core can be successfully designed with 24-month cycle and the cycle length is improved significantly with the alternative reflectors. The neutronic analyses are performed using the Monte Carlo Serpent code and 3-D diffusion code COREDAX-2 with the ENDF/B-VII.1.

Eine Studie ${\ddot{u}}$ber die Festsetzung der Behandlungsvertragspartei seitens des Patienten (진료계약의 환자 측 당사자확정에 관한 소고 -제3자 진료요청행위의 해석을 중심으로-)

  • Park, Dong Jin
    • The Korean Society of Law and Medicine
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    • v.15 no.2
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    • pp.253-283
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    • 2014
  • Ob das Erbitten der Behandlung durch einen Dritten einen Behandlungsvertrag oder lediglich eine Gesch${\ddot{a}}$ftsf${\ddot{u}}$hrung ohne Auftrag darstellt, richtet sich nach dem allgemeinen Grundsatz der Auslegung der Willenserkl${\ddot{a}}$rung. Auch wenn ein Dritter f${\ddot{u}}$r eine andere Person die Behandlung erbittet, l${\ddot{a}}$sst sich dadurch kein zwingender R${\ddot{u}}$ckschluss ziehen, dass daraus eine vertragliche Pflicht auf Verg${\ddot{u}}$tung anhand der Behandlung an den Behandlungserbitter entsteht. Das Erbitten der Behandlung eines Dritten stellt n${\ddot{a}}$mlich weder einen Antrag dar, noch ensteht dadurch ein Rechtsgesch${\ddot{a}}$ft zwischen dem Behandlungerbitter und dem Behandelnden. Stellt das Erbitten der Behandlung durch den Dritten eben kein Rechtsgesch${\ddot{a}}$ft dar, handelt es sich um eine Behandlung ohne gesetzliche Pflichten. Dadurch ist f${\ddot{u}}$r den Behandelten eine Gesch${\ddot{a}}$ftsf${\ddot{u}}$hrung ohne Auftrag er${\ddot{o}}$ffnet. Wird das Erbitten der Behandlung als Antrag ausgelegt, ist dies ein Antrag eines echten oder unechten Vertrags zugunsten Dritter, oder der Behandlungserbitter hat als Vertreter des Patienten oder Unterhaltspflichtigen als Vertretende, einen Behandlungsvertrag abgeschlossen. Wenn der Vertragspartner die Tatsache kennt oder kennen musste, dass es sich um einen Vertreter handelt, ist die Vertretungshandlung wirksam.

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Satzmodelle im Koreanischen und Deutschen im Hinblick auf ihre didaktische Verwertbarkeit ($\cdot$독 문형의 비료설정 시론)

  • Min Chun-Gi
    • Koreanishche Zeitschrift fur Deutsche Sprachwissenschaft
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    • v.7
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    • pp.85-104
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    • 2003
  • In der vorliegenden Arbeit werden die deutschen Satzmodelle $f\"{u}r$ Zwecke des DaF-Unterrichts in Korea untersucht. Dabei gehen wir davon aus, dass man die deutschen Satzmodelle vergleichend mit den koreanischen neu aufbauen sollte, um sie im Deutschunterricht fur Koraner recht benutzen zu konnen. Dafur haben wir hier zunachst untersucht, wie man die koreanischen Satzmodelle im Hinblick auf den didaktischen Zweck modifizieren muss. Unter $Ber\"{u}cksichtigung$ des dabei erzielten Ergebnisses wurden $anschlie{\ss}end$end die deutschen Satzmodelle rekonstruiert. Im Koreanischen wurden die Satzmodelle ab Ende der 1960er Jahre verschiedenartig untersucht. Zwar gibt es bisher noch keine Arbeit, die Ergebnisse dieser Forschungen zusammenfasst, dennoch versuchen wir hier aus einigen bisherigen Untersuchungen einen begrenzten Rahmen von koreanischen Satzmodellen herauszufinden. Als Resultat haben wir funf grundlegende Satzmolle hergestellt: (1) Subjekt + $Pr\"{a}dikat$, (2) Subjekt + $Pr\"{a}dikativ$ + $Pr\"{a}dikat$, (3) Subjekt + Objektiv + $Pr\"{a}dikat$, (4) Subjekt + Adverbiale + $Pr\"{a}dikat$, (5) Subjekt + Obj. + Obj./$Pr\"{a}dikativ$/Advb. + $Pr\"{a}dikat$. Das Modell (1) $umfa{\ss}t$ drei $Pr\"{a}dikate$, die sich nach den Wortarten unterscheiden: (intransitives) Verb, Adjektiv und Substantiv. Auch beim Fall (5) $k\"{o}nnen$ drei verschiedene Untermodelle nach der $Kombinationsm\"{o}glichkeit$ auftreten: Sub + Obj. + $Pr\"{a}d$., Sub. + Obj. + $Pr\"{a}dikativ$ + $Pr\"{a}d$., Sub. + Obj. + Advb. + $Pr\"{a}d$. Auch im Deutschen kann man ahnlich wie im Koreanischen didaktisch geeignete Satzmodelle herausarbeiten. Auch dabei wurden bisherige Untersuchungen zu den deutschen Satzmodellen herangewgen. Zu der $d\"{a}fur$ $ausgew\"{a}hlten$ Terminologie $geh\"{o}ren$ Subjekt(S), $Pr\"{a}dikat(P)$, $Pr\"{a}dkativerganzung(PE)$, $Objekterg\"{a}nzung(OE)$, $Adverbialerg\"{a}nzung(AE)$. In der deutschen Sprache werden nach den $Valenzm\"{o}glich­keiten$ des $Pr\"{a}dikativteils$ folgende Modelle unterschieden: S + P, S + P + PE, S + P + OE, S + P + AE, S + P + OE + OE/PE/AE. Unter die OE werden okk. OE, dat. OE, $pr\"{a}d$. OE, refl. OE usw. subsumiert. Um die Stichhaltigkeit der in dieser Schrift neu festgestellten Satzmodelle zu $\"{u}berpr\"{u}fen$, sollten sie anhand eines Textkorpus heutiger Texte in weiteren Untersuchungen validiert werden. Ferner ist es zu empfehlen, die Anwendbarkeit der hier vorgestellten Satzrnodelle im Deutschunterricht $f\"{u}r$ Koreaner $gr\"{u}ndlich$ zu testen

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Antistress effect of red ginseng in brain cells is mediated by TACE repression via PADI4

  • Kim, Eun-Hye;Kim, In-Hye;Ha, Jung-Ah;Choi, Kwang-Tae;Pyo, Suhkneung;Rhee, Dong-Kwon
    • Journal of Ginseng Research
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    • v.37 no.3
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    • pp.315-323
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    • 2013
  • Ginseng is known to have antistress effects. Previously, red ginseng (RG) was shown to repress stress-induced peptidyl arginine deiminase type IV (PADI4) via estrogen receptor ${\beta}$ ($ER{\beta}$) in the brain, thus inhibiting brain cell apoptosis. Moreover, tumor necrosis factor (TNF)-${\alpha}$ plays a critical role in immobilization (IMO) stress. However, the signaling pathway of RG-mediated repressesion of inflammation is not completely understood. In this study, we determined how RG modulated gene expression in stressed brain cells. Since secretion of TNF-${\alpha}$ is modulated via TNF-${\alpha}$ converting enzyme (TACE) and nuclear factor (NF)-${\kappa}B$, we examined the inflammatory pathway in stressed brain cells. Immunohistochemistry revealed that TACE was induced by IMO stress, but RG repressed TACE induction. Moreover, PADI4 siRNA repressed TACE expression compared to the mock transfected control suggesting that PADI4 was required for TACE expression. A reporter assay also revealed that $H_2O_2$ oxidative stress induced NF-${\kappa}B$ in neuroblastoma SK-N-SH cells, however, RG pretreatment repressed NF-${\kappa}B$ induction. These findings were supported by significant induction of nitric oxide and reactive oxygen species (ROS) by oxidative stress, which could be repressed by RG administration. Taken together, RG appeared to repress stress-induced PADI4 via TACE and NF-${\kappa}B$ in brain cells thus preventing production of ROS and subsequently protecting brain cells from apoptosis.

Oxide perovskite crystals type ABCO4:application and growth

  • Pajaczkowska, A.
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.258-292
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    • 1996
  • In the last year great interest appears to YBCO thin films preparation on different substrate materials. Preparation of epitaxial film is a very difficult problem. There are many requirements to substrate materials that must be fullfilled. Main problems are lattice mismatch (misfit) and similarity of structure. From paper [1] or follows that difference in interatomic distances and angles of substrate and film is mire important problem than similarity of structure. In this work we present interatomic distances and angle relations between substrate materials belonging to ABCO4 group (where A-Sr or Ca, B-rare earth element, C-Al or Ga) of different orientations and YBCO thin films. There are many materials used as substrates for HTsC thin films. ABCO4 group of compounds is characterized by small dielectric constants (it is necessary for microwave applications of HTsC films), absence of twins and small misfit [2]. There most interesting compounds CaNdAlO4, SrLaAlO4 and SrLaGaO4 were investigated. All these compounds are of pseudo-perovskite structure with space group 14/mmm. This structure is very similar to structure of YBCO. SLG substrate has the lowest misfit (0.3%) and dielectric constant. For preparation of then films of substrates of this group of compound plane of <100> orientation are mainly used. Good quality films of <001> orientations are obtained [3]. In this case not only a-a misfit play role, but c-3b misfit is very important too. Sometimes, for preparation of thin films substrates of <001> and <110> orientations were manufactured [3]. Different misfits for different YBCO faces have been analyzed. It has been found that the mismatching factor for (100) face is very similar to that for (001) face so there is possibility of preparation of thin films on both orientations. SrLaAlO4(SLA) and SrLaGaO4(SLG) crystals of general formula ABCO4 have been grown by the Czochralski method. The quality of SLA and SLG crystals strongly depends on axial gradient of temperature and growth and rotation rates. High quality crystals were obtained at axial gradient of temperature near crystal-melt interface lower than 50℃/cm, growth rate 1-3 mm/h and the rotation rate changing from 10-20pm[4]. Strong anisotropy in morphology of SLA and SLG single crystals grown by the Czochralski method is clearly visible. On the basics of our considerations for ABCO4 type of the tetragonal crystals there can appear {001}, {101}, and {110} faces for ionic type model [5]. Morphology of these crystals depend on ionic-covalent character of bonding and crystal growth parameters. Point defects are observed in crystals and they are reflected in color changes (colorless, yellow, green). Point defects are detected in directions perpendicular to oxide planes and are connected with instability of oxygen position in lattice. To investigate facets formations crystals were doped with Cr3+, Er3+, Pr3+, Ba2+. Chromium greater size ion which is substituted for Al3+ clearly induces faceting. There appear easy {110} faces and SLA crystals crack even then the amount of Cr is below 0.3at.% SLG single crystals are not so sensitive to the content of chromium ions. It was also found that if {110} face appears at the beginning of growth process the crystal changes its color on the plane {110} but it happens only on the shoulder part. The projection of {110} face has a great amount of oxygen positions which can be easy defected. Pure and doped SLA and SLG crystals measured by EPR in the<110> direction show more intensive lines than in other directions which allows to suggest that the amount of oxygen defects on the {110} plane is higher. In order to find the origin of colors and their relation with the crystal stability, a set of SLA and SLG crystals were investigated using optical spectroscopy. The colored samples exhibit an absorption band stretching from the UV absorption edge of the crystal, from about 240 nm to about 550 m. In the case of colorless sample, the absorption spectrum consists of a relatively weak band in the UV region. The spectral position and intensities of absorption bands of SLA are typical for imperfection similar to color centers which may be created in most of oxide crystals by UV and X-radiation. It is pointed out that crystal growth process of polycomponent oxide crystals by Czochralski method depends on the preparation of melt and its stoichiometry, orientation of seed, gradient of temperature at crystal-melt interface, parameters of growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth (rotation and pulling rate) and control of red-ox atmosphere during seeding and growth. Growth parameters have an influence on the morphology of crystal-melt interface, type and concentration of defects.

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Growth Regulation of Korean Lawngrass and Manilagrass with Several Growth Retardants (잔디류식물에 있어 생장억제제시용효과에 관한 연구)

  • 심재성
    • Asian Journal of Turfgrass Science
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    • v.3 no.1
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    • pp.39-52
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    • 1989
  • Native Kerean lawngrass (Zeysia japonica steud.) and Manilagrass ( Zeysia matrella Merr.) are frequently used as sport turf and lawn in Kerea and ether Asian countries because of its excellent summer qualities and superior winter-hardiness compared to ether warm-season turfgrass . The objective of this study was to investigate the effect of the plant growth retardants ( PGR ) en the inhibition (d the growth of the two Kerean native turfgrasses. Kerean lawngrass and Manilagrass were treated with [2 RS , 3 RS] -1- [4- chlorophenyl ] -4, 4-dimethyl -2- [1 H -1, 2, 4- tiazol -1- y] pentan -3- ol ( PP -333) at 93 and 930 gha -j ; 5-[4- chlorphenyl ]-3, 4, 5, 9, 10- peiitaaza - tetracyclo [5, 4, 1, 0 2 6 . o ~'~I -3, 9- diene ( BAS -106) at 16 and 160 gha ; [ E I-] - cyclohexyl -4, 4- dimethyl -2- [1, 2, 4- triazol -1- yl ]-1-pentene - 3- ol ( NTN -821) at 56 and 560 gha ', and 4- chloro -2- [$\alpha$- hydrozybenzy I isonicotin anilide ( CGR -811) at 92 gha in pot study . All PGR treatments were effective in reducing the plant height, with the exception of BAS -106 at 16 gha for Korean lawngrass ; however , all increased quality to some degree , with the exception of PP -333 at 93 gha . The low PGR rates significantly increased Korean lawngrass height during late jtily aitd mid-August . On the other hand , BAS -106 significantly increased Manilagrass height {rom 24 Septeml)er onwards . All PGR treatments haol higher turfgrass quality than untreatments , and also the high rates of PGIt treatments were more effective in increasing quality than the low rates observed on 8 October . Meanwhile , Manilagrass quality was increased to some extent than Korean lawegrass . PP - 333 was significantly effective in reducing clipping yield and the same results were found with the application of NTN -821 at 560 gha -l for both Korean lawngrass and Manilagrass , BAS -106 at 160 gha for Korean lawegrass , and CGR -811 at 92 gha for Manilagrass . The high PGR rates had higher turfgrass shoot weight observed on 8 October than the low rates , and there were little increases obtained with the low rates of PP -333 for Korean lawngrass and BAS - 1 06 for Manilagrass . Effeets on stolon growth varied between growth retardants , and between retardant treatments ; the high rates of PGR as well as the low rate of NTN -821 elongated stolon of Korean lawngrass and manoilagrass . However , PP -333 at 93 gha and BAS -106 at 16 gha - shortened stolons of Korean lawugrass , resulting in inhibition or little difference of stolon dry weight . NTN -821 at 560 gha and CGR -811 had no positive effect on the stolon length of Manilagrass . 101) -333 and the low rate of BAS -106 and NTN -821 decreased root weight of Korean lawng - rass All PGR rates had negative effect on the root weight of Manilagrass with the exception of BAS -106 CR -811 and the high rate of NTN -821 which made no difference in root weight between retarolant treatments and the control .

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