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Use of Dactylaria brochopaga, a Predacious Fungus, for Managing Root-Knot Disease of Wheat (Triticum aestivum) Caused by Meloidogyne graminicola

  • Kumar, Niranjan;Singh, K.P.
    • Mycobiology
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    • v.39 no.2
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    • pp.113-117
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    • 2011
  • A laboratory experiment was conducted to study the induction of constricting rings and test predation of Dactylaria brochopaga isolates against second stage juveniles (J2s) of Meloidogyne graminicola. Among the five fungal isolates, isolate D showed the greatest number of predatory rings and, consequently, trapped the maximum number of M. graminicola J2s in dual cultures. Another pot experiment was conducted to study the effect of D. brochopaga (isolate D) on the management of wheat root-knot disease. Applying a mass culture (10 g/pot) and a spore suspension of the fungus with and without cow dung manure to soil infested with 2,000 M. graminicola juveniles significantly improved plant height, root length, weights of shoots, roots, panicles and grains per hill compared to those in the control. Moreover, the fungus significantly reduced the number of root-knots, the number of egg masses, juveniles, and females per hill compared to those in the control. Bio-efficacy of the fungus was heightened when the mass culture and a spore suspensions were used in combination with cow dung manure to improve the plant growth parameters and reduce the number of root-knot and reproductive factors. Further investigations should be conducted to identify the impact of this fungus in the field.

The Existence of Random Walk in the Philippine Stock Market: Evidence from Unit Root and Variance-Ratio Tests

  • CAMBA, Abraham C. Jr.;CAMBA, Aileen L.
    • The Journal of Asian Finance, Economics and Business
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    • v.7 no.10
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    • pp.523-530
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    • 2020
  • The efficient market hypothesis explains the random walk hypothesis suggesting that stock prices are independent of each other, hence, it is impossible to earn abnormal profits. The positive effect of a well-functioning and highly efficient stock market on the performance of an economy motivated the Philippine Stock Exchange to pursue massive modernization initiatives. This research provides evidence of the existence of random walk in the Philippine stock market employing the Augmented Dickey-Fuller (1981) and Phillips-Perron (1988) unit root tests, the Lo-MacKinlay's (1988) conventional variance ratio test, and Chow-Denning's (1993) simple multiple variance ratio test. Results of the ADF and PP unit root tests confirm the necessary condition for a random walk. The Chow-Denning (1993) maximum /z/ statistic and the Wald test statistic as in Richardson and Smith (1991) for the joint hypotheses and the Lo and MacKinlay (1988) individual statistics variance ratio test generally accepted the null hypothesis of a random walk. That is, the unit root and variance ratio tests consistently indicate that the null hypothesis of random walk cannot be rejected. The existence of a random walk in weak-form efficiency can be attributed to market liquidity as a result of continuous development and modernization of the Philippine equity market.

Local ratcheting behavior in notched 1045 steel plates

  • Kolasangiani, K.;Farhangdoost, K.;Shariati, M.;Varvani-Farahani, A.
    • Steel and Composite Structures
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    • v.28 no.1
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    • pp.1-11
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    • 2018
  • In this paper, local ratcheting behavior of 1045 steel plates with circular cutout was investigated. Experimental tests were carried out by a Zwick/Roell HB 100 servo hydraulic machine. In order to measure the local strain at notch root, a data acquisition system with strain gauge was used. Various notch diameters and distances of strain gauges mounted from the notch root were found influential in the magnitude of local ratcheting strain. It was found that the local maximum principal stress plays a crucial role in increasing the local plastic deformation. Numerical simulation was done by ABAQUS software using nonlinear isotropic/kinematic hardening model. Material parameters of hardening model were attained from several stabilized cycles of flat specimens subjected to symmetric strain cycles. The nonlinear kinematic hardening model along with the Neuber's rule was employed to assess local ratcheting at the notch root of steel plates. The results of the numerical simulations agreed closely with those measured values in this study. Both ratcheting progress and mean stress relaxation occurred simultaneously at the notch root.

Screening and Identification of Antibacterial Actinomycetes against Bacteria Causing Rusty Root on Ginseng (인삼의 적변을 유발하는 세균에 대하여 항균활성을 가지는 방선균 선발 및 동정)

  • Han, Sung-Hee;Ryu, Dong-Kul;Choi, Seung-Hyun;Choi, Jae-Eul;An, Gilh-Wan
    • Korean Journal of Agricultural Science
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    • v.37 no.2
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    • pp.255-260
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    • 2010
  • Rusty root, the browning disease on ginseng, decreases quality and value. Recent studies indicated that endophytic bacteria could be a possible cause of rusty root. Actinomycetes antagonistic to the rusty-root-causing bacteria were isolated from soil. Twenty nine out of 932-isolates of Actinomycetes from soil showed antibacterial activity against Agrobacterium tumefaciens and Pseudomonas veronii an endophytic isolate in ginseng. The strongest antibacterial strain(ATO4O104) was classified based on 16S rDNA sequence. The Actinomycetes strain, ATO4O104, isolated in soil of USA volcano national park was identified as Streptomyces adephospholyticus. To test plant toxicity, radish seeds were sprouted with the culture of S. adephospholyticus and it did not show any harmful effect. The butanol partition out of n-hexane, ethyl acetate, butanol, and water partions showed the highest antibacterial activity.

Nematicidal Compounds from the Leaves of Schinus terebinthifolius Against Root-knot Nematode, Meloidogyne incognita Infecting Tomato

  • Abdel Bar, Fatma M.;Ibrahim, Dina S.;Gedara, Sahar R.;Abdel-Raziq, Mohammed S.;Zaghloul, Ahmed M.
    • Natural Product Sciences
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    • v.24 no.4
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    • pp.272-283
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    • 2018
  • The root-knot nematode, Meloidogyne incognita caused a serious damage to many plants. The phenolic components of the leaves of Schinus terebinthifolius were investigated as potential nematicidal agents for M. incognita. Nine compounds were isolated and characterized as viz., 1,2,3,4,6-pentagalloyl glucose (1), kaempferol-3-O-${\alpha}$-L-rhamnoside (Afzelin) (2), quercetin-3-O-${\alpha}$-L-rhamnoside (Quercetrin) (3), myricetin (4), myricetin-3-O-${\alpha}$-L-rhamnoside (Myricetrin) (5), methylgallate (6), protocatechuic acid (7), quercetin (8), and gallic acid (9) using nuclear magnetic resonance (NMR) spectroscopy. Compound 1 showed pronounced nematicidal activity compared to Oxamyl as a positive control. It showed the lowest eggs-hatchability (34%) and the highest mortality in nematode population (21% after 72 hours of treatment) at a concentration of $200{\mu}g/mL$. It exhibited the best suppressed total nematode population, root galling and number of eggmasses in infected tomato plants. The total carbohydrates and proteins were also significantly induced by 1 with reduction in total phenolics and increase in defense-related proteins. Thus, compound 1 could be a promising, more safe and effective natural nematicidal agent for the control of root-knot nematodes.

Root Cause Analysis of Medical Accidents -Using Medical Accident Cases (의료사고의 근본원인 분석: 의료사고 판례문 이용)

  • KIM, Seon-Nyeo;Cho, Duk-Young
    • The Korean Journal of Health Service Management
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    • v.13 no.3
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    • pp.13-26
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    • 2019
  • Objectives: To investigate whether medical institutions can prevent accidents by analyzing the root cause of a medical accident and identifying the tendencies. Methods: A total of 345 medical cases were used for the RCA(Root Cause Analysis). The root causes were classified using the SHELL model. The suitability of the model was confirmed by SPSS's MDPREF and Euclidean distance. An SPSS20.0 hierarchical regression analysis was used as an influencing factor on the degree of injury resulting from medical accidents. Results: The SHELL model was suitable for classification. The rates of accident causes were LS49%, L34%, LL10.2%, LE3.7%, LH2.3%. The order in which the degree of a patient's injury was affected were: Risk Threshold (${\beta}=.180$), Time (${\beta}=.175$), Surgical stage (${\beta}=-.166$), Do not use procedure (${\beta}=.147$). Conclusions: Health care institutions should remove priorities through system improvement and training. For patients' safety, the five factors of the SHELL model should be managed in harmony.

Correlations among Agronomic Characters of Ginseng Plants (인삼의 각종 주요형질간의 상관관계)

  • Choi, K.T.;Ahn, T.S.;Shin, H.S.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.25 no.3
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    • pp.63-67
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    • 1980
  • This study was carried out to seek the visible marker and make it easy to select the individuals or lines which have excellent characters. Ginseng plants of one to five years were used for this study, and agronomic characters, such as stem diameter. stem length, leaf length, leaf width, petiole length. stem weight, leaf weight, number of leaves, number of leaflets, main root length, root length, root diameter and root weight were determined and correlations among them were estimated. Generally, agronomic characters, such as stem diameter, leaf length, leaf width, number of leaves, number of leaflets, leaf weight and stem weight had positive and highly significant correlations with root weight per plant, the character that has great influence on yield.

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Qualitative and quantitative evaluation of root injury risk potentially burdening insertion of miniscrew implants

  • Antoszewska, Joanna;Trzesniewska, Paulina;Kawala, Beata;Ludwig, Bjorn;Park, Hyo-Sang
    • The korean journal of orthodontics
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    • v.41 no.2
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    • pp.112-120
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    • 2011
  • Objective: Microscrew implants (MSls) offer many advantages, but some complications are known to occur during their insertion. One of the most commonly reported complications is root injury. Our aim was to identify factors associated with root injury and to evaluate their qualitative and quantitative values. Methods: Thirty-five orthodontists placed MSls (AbsoAnchor$AbsoAnchor^{(R)}$, Dentos Co. Ltd, Daegu, Korea) in the upper jaw of typodonts, labially between the second premolar and the first molar, in low and high vertical positions. Root contacts were counted, and distances between MSI apices and roots were measured. Fear level of the orthodontists was surveyed before and after the experiment. Wilcoxon's test, chi-square test, and Mann-Whitney test were used for statistical analysis. Results: Overall root contact rate of MSI insertion was 23.57%. The root contact rate was significantly higher in MSls inserted at $90^{\circ}$ (45.71%) than at $30^{\circ}$ (1.43%). The distance between the dental root and MSI also increased significantly in MSls inserted at $30^{\circ}$. Mean fear level before MSI insertion (4.6) significantly decreased after insertion (3.2); the causative factors were risk of injury to dental root and maxillary sinus or mandibular canal. Conclusions: Root injury is relatively rare, and oblique angulation reduces the risk of root and MSI contact.

A STUDY ON COMPARISON OF STAINLESS STEEL, NICKEL-TITANIUM HAND, NICKEL-TITANIUM ENGINE-DRIVEN FILE INSTRUMENTATION USING COMPUTED TOMOGRAPHY (수동형 Stainless Steel, Nickel-Titanium 및 엔진 구동형 Nickel-Titanium File의 근관형성 능력에 관한 비교 연구)

  • Lee, Hwang;Im, Mi-Kyung;Lee, Keon-Il;Lee, Yong-Keun
    • Restorative Dentistry and Endodontics
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    • v.23 no.1
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    • pp.391-400
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    • 1998
  • The aim of this study was to determine the shaping ability of stainless-steel K file (S-S K file), nickel-titanium K file (Ni-Ti K file) and engine driven nickel-titanium file (Quantec file) in resin simulated root canal. Computed tomography was used to evaluate the change of the root canal morphology. Thirty nine resin simulated root canal were divided into four groups (A:12, B:12, C:12, D:3). Resin simulated canals were scanned by computed tomography before instrumentation (1st C-T scan). Canals were instrumented using step back preparation technique with S-S K file in group A and Ni-Ti K file in group B. Group C was prepared with engine driven Ni-Ti file. Group D was uninstrumented to compare the 1st C-T scan images with 2nd C-T scan images of root canal. Instrumented canals were again scanned using computed tomography (2nd C-T scan), and reformated images of the uninstrumented canals were compared with images of the instrumented canals. In the sections of 2mm and 6mm from the apex, Quantec file caused significantly less canal transportation than S-S K file and Ni-Ti K file (p<0.05). Quantec file produced more centered than S-S K file and Ni-Ti K file in the sections of 2mm and 4mm from the apex (p<0.05). There was no significant difference in the removed volume of canals among the each groups (p>0.05). However the removed canal volume from the apex to 5mm were significantly higher than them from 5mm to 1mm (p<0.05) in each groups. Under the conditions of this study, preparation with Quantec file was more effective and produce more appropriate canal shapes than S-S K file and Ni-Ti K file.

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ARREST OF ROOT DEVELOPMENT AFTER SURGICAL REPOSITIONING OF THE INVERTED MAXILLARY CENTRAL INCISOR : CASE REPORT (역위 매복된 상악 중절치의 외과적 재위치 후 치근 발육 정지)

  • Song, Je-Seon;Choi, Byung-Jai;Choi, Huung-Jun;Kim, Seong-Oh;Son, Heung-Gyu;Lee, Jae-Ho
    • Journal of the korean academy of Pediatric Dentistry
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    • v.34 no.1
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    • pp.162-168
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    • 2007
  • Impaction of the maxillary central incisor may cause social, esthetic, and functional problems in children. There are various means of treatment for the inverted maxillary central incisor, such as extraction, surgical opening followed by orthodontic traction surgical repositioning or intra-alveolar autotransplantation prior to extraction. In this case, we surgically repositioned the inverted maxillary central incisor to normal semi-erupted position in a 5-year-old boy The developmental stage of the inverted tooth was Nolla's 6.5, which indicates formation of less than one third of the root. After surgical reposition, we did follow-up for 21 months, expecting spontaneous growth Unfortunately, poor prognosis was noted further root was not observed. Such failure seems to originate from possible injury on Hertwig's epithelial root sheath by surgical trauma. We performed surgical repositioning to retain the tooth instead of extraction. However, arrest of root development occurred which is one of the critical complications. In order to increase the success rate of the surgical reposition procedure, minimal surgical trauma is required as well as selection of adequate indication and decision of proper time of treatment considering the stage of root development.

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