• Journal of Plant Biotechnology
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• 제30권3호
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• pp.241-244
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• 2003

Root cluster section culture, showing high efficient Protocorm-like body (PLB) formation capacity, were established in Doritaenopsis hybrids. Three types of root were obtained from excised shoots in 1/2MS medium containing different concentrations of NAA; \circled1normal roots, \circled2multiple roots and \circled3abnormal root clusters. Those were placed on 1/2MS medium supplemented with 0.5 mg/L thidiazuron for PLB regeneration. PLB regeneration rate was greater in root cluster section cultures (77.8%) compare to normal root tip cultures(30%). Number of PLBs regenerated from root cluster sections were counted over 11 per explant (5.3 per normal root tip).High frequency of PLB regeneration was achieved in root cluster section culture. This result can be used as an efficient method for clonal proliferation of Doritaenopsis hybrids.

• Communications for Statistical Applications and Methods
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• 제2권2호
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• pp.101-114
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• 1995

In this paper we consider the multiple unit root tests both for the regular and seasonal unit roots based on the Lagrange Multiplier(LM) principle. Unlike Li(1991)'s method, by plugging the restricted maximum likelihood estimates of the nuisance parameters in the model, we propose a Lagrange multiplier test which does not depend on the existence of the nuisance parameters. The asymptotic distribution of the proposed statistic is derived and empirical percentiles of the test statistic for selected seasonal periods are provided. The power and size of the test statistic for examined for finite samples through a Monte Carlo simularion.

• 대한소아치과학회지
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• 제51권1호
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• pp.88-98
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• 2024

Patients with pediatric cancer often undergo multiple therapies, such as chemotherapy, radiation therapy, and stem cell transplantation. These treatments, while essential, can result in dental developmental issues, including hypodontia, microdontia, short roots, and delayed dental development. This report presents two cases of pediatric patients diagnosed with neuroblastoma who exhibited severe tooth mobility due to short roots as a complication of cancer treatment. Moreover, we investigated the conservative management of the patients' conditions using resin wire splints and orthodontic miniscrews for skeletal anchorage along with long-term follow-ups to evaluate their prognosis.

• 식물조직배양학회지
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• 제21권4호
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• pp.247-252
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• 1994

조직배양을 통한 대량증식을 목적으로 구문초 (Pelalgonium citrosa)의 엽신, 엽병 및 정단분열조직을 auxin류와 cytokinin류의 생장조절제를 혼합첨가한 MS배지에 배양한 후 캘러스발생 및 shoot분화율을 조사하였고, 분화된 shoot는 NAA와 IAA가 단독첨가된 MS배지에 옮겨 뿌리분화율을 조사하였다. 생장조절제의 효과는 2,4-D와 kinetin의 혼용처리보다 NAA와 BA첨가배지에서 엽신, 엽병조직 모두 캘러스발생 및 multiple shoot분화가 양호하였다. 엽신조직의 경우 암배양 상태에서 캘러스와 shoot의 분화가 좋았고, 0.5 mg/L NAA와 BA 혼용배지에서는 정상적 민 shoot가 분화된 반면 NAA와 BA의 농도가 높을 경우 분화된 shoot는 vitrification현상이 비교적 많이 나타난다. Shoot는 캘러스를 통하거나 직접 절편체에서 분화되었는데 1개의 절편당 shoot분화수는 캘러스를 통해 분화된 경우가 훨씬 많았다. 엽보의 경우 캘러스발생 및 shoot분화양상은 엽신과 비슷하였으나 분화된 shoot수는 훨씬 적었다. 정단분열조직에서 캘러스증식율이 가장 좋았으며 shoot분화는 NAA와 BA 0.5mg/L첨가구에서 양호하여 대량증식에 가장 효과적인 반응이었다. Shoot로부터 뿌리발생은 1.0 mg/L NAA 첨가배지에서 가장 효과적이었다.

• 한국정밀공학회지
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• 제13권2호
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• pp.76-83
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• 1996

We have developed the unconventional robot arm which is composed of the two main parts, one is a ball screw and the other is a robot arm. The dynamic systems of the robot arm and ball screw are unstable systems coupled with each other. The ball screw mechanism is unstable system but controllable system. The robot arm's dynamics is quasi stable system when ball screw's angular position is zero, else, unstable system. Our system has the duality between stability and controllability at the view point of control. This duality causes difficulty to control of the robot arm using normal control law. We have investigated the location of the characteristic roots of the dynamic equation. And we have found out that the best condition for the control of the arm is quasi stable state. In this paper, we have proposed multiple control laws which are consist of three components to guarantee the stability and controllability simultaneously. The computer simulations were carried out based on VSC about the angular position control of the robot arm, and it is confirmed that the good performances could be obtained by using new controller.

• 식물조직배양학회지
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• 제27권3호
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• pp.197-202
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• 2000

조직배양을 이용한 처녀치마 대량증식을 위한 적정배지, 생장조절제 및 농도구명을 위해 본 연구를 수행하였다. Shootb 및 roots분화의 경우 zeatin 3.0 mgι$^{-1}$을 첨가한 MS 배지에서 shoots및 roots 형성률이 각각 20, 30%로서 가장 양호한 것으로 나타났다. 1/2 MS배지의 경우 zeatin 1.0mgι$^{-1}$에서 shoots 형성률이 67 %, B5 배지에 있어서 zeatin 3.0 mgι$^{-1}$ 처리에서 33 %로 가장 양호한 것으로 나타났다. 배지에 따른 식물 생장조절제 처리에 따른 식물체 분화율은 MS 배지에서는 2,4-D 0.5 mgι$^{-1}$, 1/2 MS 배지에서 zeatin 1.0 mgι$^{-1}$ 및 B5 배지에서 reatin 3.0 mgι$^{-1}$에서 자장 가장 많은 100, 193, 280 및 310%의 분화된 식물체를 얻을 수 있었다. 전반적으로 야생화인 처녀치마의 잎 조직으로부터 multiple shoots을 유도하여 대량증식을 위한 목적으로는 B5 배지에 생장조절제인 zeatin 3.0 mgι$^{-1}$을 첨가시키는 것이 가장 효과적인 것으로 나타났다.

• Journal of Plant Biotechnology
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• 제47권1호
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• pp.40-45
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• 2020

An efficient protocol for multiple shoot induction and plant regeneration from axillary bud culture of Magnolia 'Vulcan' was developed in the present study. Primary shoots were obtained from axillary bud explants cultured on Murashige and Skoog (MS) medium containing 1.0 mg/L 6-benzylaminopurine (BA). To induce multiple shoots effectively, primary shoot tips were cultured on MS medium supplemented with different concentrations of BA and zeatin at 0, 0.2, 0.5, and 1.0 mg/L. Of these treatments, the MS medium with 0.5 mg/L BA resulted in the highest number of shoots per explant with an average value of 5.9, and it produced the greatest shoot height at 4.8 cm after 12 weeks of culturing. In the rooting of in vitro produced shoots, the greatest percentage of explants forming roots (91.3%), number of roots per explant (9.7), and root length (2.8 cm) were obtained in half-strength MS medium supplemented with 6.0 mg/L indole-3-butyric acid (IBA). Regenerated plantlets were successfully acclimatized and hardened off inside the culture room with 87.5% survival rate. Plants were transferred to a greenhouse with a 97.2% survival rate. The highly efficient shoot multiplication and plant regeneration system reported herein can be used for large-scale clonal propagation of valuable Magnolia species or cultivars.

• 대한수학회지
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• 제59권6호
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• pp.1067-1082
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• 2022

This paper presents a new optimal three-step eighth-order family of iterative methods for finding multiple roots of nonlinear equations. Different from the all existing optimal methods of the eighth-order, the new iterative scheme is constructed using one function and three derivative evaluations per iteration, preserving the efficiency and optimality in the sense of Kung-Traub's conjecture. Theoretical results are verified through several standard numerical test examples. The basins of attraction for several polynomials are also given to illustrate the dynamical behaviour and the obtained results show better stability compared to the recently developed optimal methods.

• Journal of Dental Anesthesia and Pain Medicine
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• 제19권4호
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• pp.239-244
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• 2019

The effectiveness of dental implants in patients with disability, who are non-compliant during treatment, is controversial because of their poor oral health. Thus, oral health-care and management in such patients is concerning. Moreover, limited information is available on prognosis after implant placement. Herein, we describe a patient with schizophrenia who underwent dental implantation under multiple inductions of general anesthesia (5 times) and required conservative treatment and tooth extraction for multiple dental caries and retained roots because of inadequate oral health-care. Postoperatively, fracture of the prosthodontics and progression of dental caries were observed, and with 3 additional inductions of general anesthesia, conservative treatment, implant surgery, and prosthesis implantation were conducted. Postoperative 12-month follow-up since the last prosthesis implantation showed successful results. For patients with schizophrenia, multiple implantation can reduce horizontal bone loss and achieve aesthetic results compared to treatment with removable prosthodontics and could serve as an alternative treatment modality.

• 치과방사선
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• 제19권1호
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• pp.31-37
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• 1989

The author observed a rare case of radicular dentin dysplasia associated with enamel hypoplasia in a 11-year-old boy with a complaint of gum boil formation. 1. Clinically. yellowish-brown colored teeth with severe attrition and several gum boils were observed. 2. Radiographically, obliteration of pulp chamber and root canal, multiple periapical radiolucencies without obvious cause and blunt roots were observed. 3. Systemically, scalp hair and eyebrows were loose and short. And saddle nose could be also seen.