• Title/Summary/Keyword: Direct Modification

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Oral Lichen Planus and Oral Lichenoid Lesion: Diagnosis and Assessment of Direct Immunofluorescence

  • Lee, Kyung-Eun
    • Journal of Oral Medicine and Pain
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    • v.41 no.3
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    • pp.91-98
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    • 2016
  • Purpose: Oral lichen planus (OLP) has generated many discussions and been associated with much controversy for a long time. A reliable diagnosis of OLP has proven challenging and significant disagreements concerning its diagnosis has continued. Therefore, the aim of this study was to apprehend newly proposed diagnostic criteria of OLP and oral lichenoid lesion (OLL) and to evaluate difference of final diagnosis of OLP and OLL in accordance with type of diagnostic criteria. Also, direct immunofluorescence (DIF) was compared to evaluate the value of DIF between two groups. Methods: Fifty-two patients with DIF result were retrospectively reviewed. The selected patients were classified by the modified World Health Organization (WHO) diagnostic criteria of OLP and OLL and by criteria proposed by American Academy of Oral and Maxillofacial Pathology (AAOMP). Results of DIF in OLP and OLL were classified by deposition intensity or pattern of fibrinogen. The classification of fluorescence pattern in each specimen was graded as positive, possibly positive or negative. Results: Patients diagnosed as OLP were a few more when the modified WHO diagnostic criteria were used than when criteria proposed by AAOMP were used. There was no statistical difference of DIF between OLP and OLL by applying the WHO modification criteria or criteria proposed by AAOMP. Conclusions: The final diagnosis of OLP could be changed in accordance with type of diagnostic criteria and difference of DIF between OLP and OLL was not found.

INFLUENCE OF DIRECT-FED MICROBIALS ON RUMINAL MICROBIAL FERMENTATION AND PERFORMANCE OF RUMINANTS: A REVIEW

  • Yoon, I.K.;Stern, M.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.8 no.6
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    • pp.533-555
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    • 1995
  • Direct-fed microbials (DFM) have been used to enhance milk production in lactating cattle and to increase feed efficiency and body weight gain in growing ruminants. Primary microorganisms that have been used as DFM for ruminants are fungal cultures including Aspergillus oryzae and Saccharomyces cerevisiae and lactic acid bacteria such as Lactobacillus or Streptococcus. Attempts have been made to determine the basic mechanisms describing beneficial effects of DFM supplements. Various modes of action for DFM have been suggested including : stimulation of ruminal microbial growth, stabilization of ruminal pH, changes in ruminal microbial fermentation pattern, increases in digestibility of nutrients ingested, greater nutrient flow to the small intestine, greater nutrient retention and alleviation of stress, however, these responses have not been observed consistently. Variations in microbial supplements, dosage level, production level and age of the animal, diet and environmental condition or various combinations of the above may partially explain the inconsistencies in response. This review summarizes production responses that have been observed under various conditions with supplemental DFM and also corresponding modification of ruminal fermentation and other changes in the gastrointestinal tract of ruminant animals.

Strategic Application of Epigenetic Regulators for Efficient Neuronal Reprogramming of Human Fibroblasts

  • Gary Stanley Fernandes;Rishabh Deo Singh;Debojyoti De;Kyeong Kyu Kim
    • International Journal of Stem Cells
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    • v.16 no.2
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    • pp.156-167
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    • 2023
  • Background and Objectives: Cellular reprogramming in regenerative medicine holds great promise for treating patients with neurological disorders. In this regard, small molecule-mediated cellular conversion has attracted special attention because of its ease of reproducibility, applicability, and fewer safety concerns. However, currently available protocols for the direct conversion of somatic cells to neurons are limited in clinical application due of their complex nature, lengthy process, and low conversion efficiency. Methods and Results: Here, we report a new protocol involving chemical-based direct conversion of human fibroblasts (HF) to matured neuron-like cells with a short duration and high conversion efficiency using temporal and strategic dual epigenetic regulation. In this protocol, epigenetic modulation by inhibition of histone deacetylase and bromodomain enabled to overcome "recalcitrant" nature of adult fibroblasts and shorten the duration of neuronal reprogramming. We further observed that an extended epigenetic regulation is necessary to maintain the induced neuronal program to generate a homogenous population of neuron-like cells. Conclusions: Therefore, our study provides a new protocol to produce neurons-like cells and highlights the need of proper epigenetic resetting to establish and maintain neuronal program in HF.

Membrane Surface Modification through Direct Fluorination for Gas-Liquid Contactor (막접촉기 응용을 위한 직접 불소화를 통한 막의 표면개질)

  • Lee, Hyung-Keun;Park, Bo-Ryoung;Rhim, Ji-Won;Lee, Sang-Yun;Hwang, Taek-Sung
    • Membrane Journal
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    • v.17 no.4
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    • pp.345-351
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    • 2007
  • In this research, by using the fluorine gas, the poly(ether sulfone) (PES), the polysulfone (PSf), and the poly-vinylidenefluoride (PVDF) membranes were modified to improve the performance of the optional Gas-Liquid Contactor The SEM, surface contact angle, XPS, and the water transmission minimum pressure test was performed in order to examine the characteristics of which is surface modified. As a result of looking into the surface morphology of from the SEM measurement, we could know that the roughness of the membrane surface increased as the fluorine processing time increased. $-CH_2$, and the perfluoro group of $-CH_3$ were chemically combined with the surface fluorine conversion film surface and the hydrophobicity was exposed to be increased. Moreover, we could know that as the surface fluorinated processing time increased from the surface contact angle and water transmission minimum pressure test, the measured value increased and the overall characteristics were improved.

Static and Dynamic Analysis of Plate Structures using a High Performance Finite Element (고성능 유한요소를 이용한 평판구조물의 정적 및 동적해석)

  • Han In-Seon;Kim Sun-Hoon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.18 no.3
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    • pp.311-320
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    • 2005
  • In this paper an enhanced quadratic finite element for static and dynamic analysis of plate structures is presented. The performance of a proposed plate element is improved by the coupled use of non conforming displacement modes, the selective integration scheme, and the assumed shear strain fields. An efficient direct modification method is also applied to this element to solve the problem such as failure of the patch test due to the adoption of non conforming modes. The proposed quadratic finite element does not show any spurious mechanism and does not produce shear locking phenomena even with distorted meshes. It is shown that the results obtained by this element converged to analytical solutions very rapidly tough numerical tests for standard benchmark problems. It is also noted that this element is applicable to transient dynamic analysis of Mindlin plates.

A Four-node General Shell Element with Drilling DOFs (면내회전자유도를 갖는 4절점 곡면 쉘요소)

  • Chung, Keun-Young;Kim, Jae-Min;Lee, Eun-Haeng
    • Journal of the Earthquake Engineering Society of Korea
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    • v.16 no.4
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    • pp.37-52
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    • 2012
  • In this study, a new 4-node general shell element with 6 DOFs per node is presented. Drilling rotational degrees of freedom are introduced by the variational principle with an independent rotation field. In formulation of the element, substitute transverse shear strain fields are used to avoid shear locking, while four nonconforming modes are applied in the in-plane displacement fields as a remedy for membrane locking. In addition, a direct modification method for nonconforming modes is employed in the numerical implementation of nonconforming modes to represent constant strain states. A 9-points integration rule is adopted for volume integration in the computation of the element stiffness matrix. With the combined use of these techniques, the developed shell element has no spurious zero energy modes, and can represent a constant strain state. Several numerical tests are carried out to evaluate the performance of the new element developed. The test results show that the behavior of the elements is satisfactory.

Model Updating Method Based on Mode Decoupling Controller with Incomplete Modal Data (불완전 모달 정보를 이용한 모드 분리 제어기 기반의 모델 개선법)

  • Ha, Jae-Hoon;Park, Youn-Sik;Park, Young-Jin
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2005.11a
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    • pp.963-966
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    • 2005
  • Model updating method is known to the area to correct finite element models by the results of the experimental modal analysis. Most common methods in model updating depend on a parametric model of the structure. In this case, the number of parameters is normally smaller than that of modal data obtained from an experiment. In order to overcome this limitation, many researchers are trying to get modal data as many as possible to date. 1 want to name this method multiple modified-system generation method. These Methods consist of direct system modification method and feedback controller method. The direct system modification Is to add a mass or stiffness on the original structure or perturb the boundary conditions. The feedback controller method is to make the closed food system with sensor and actuator so as to get the closed loop modal data. In this paper, we need to focus on the feedback controller method because of its simplicity. Several methods related the feedback controller methods are virtual passive controller (VPC) sensitivity enhancement controller (SEC) and mode decoupling controller (MDC). Among them, we will apply MDC to the model updating problem. MDC has various advantages compared with other controllers, such as VPC and SEC. To begin with, only the target mode can be changed without changing modal property of non-target modes. In addition, it is possible to fix any modes if the number of sensors is equal to that of the system modes. Finally, the required control power to achieve desired change of target mode is always lower than those of other methods such as VPC. However, MDC can make the closed loop system unstable when using incomplete modal data. So we need to take action to avoid undesirable instability from incomplete modal data. In this paper, we address the method to design the unique and robust MDD obtained from incomplete modal data. The associated simulation will be Incorporated to demonstrate the usefulness of this method.

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Synthesis and Physical Properties of Hyperbranched Aromatic Polyamide (고차가지구조 방향족 폴리아미드의 합성 및 물성)

  • Ok Chang-Yul;Kim Jang-Yup;Huh Wansoo;Lee Sang-Won
    • Polymer(Korea)
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    • v.29 no.6
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    • pp.571-574
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    • 2005
  • The aromatic hyperbranched polyamide was synthesized from 5-aminoisophthalic acid by direct polycondensation with triphenylphosphite (TPP) catalyst as a condensing agent. The modification of end-groups in the resulting hyperbranched polymer (HBP) with various alkyl alcohols were conducted. The modification of end-groups of HBP by alkyl groups resulted in an improved solubility in the THF comparing to that of the carboxylic acid-terminated aromatic HBP, Also, 10 wt$\%$ weight loss temperature decreased by increasing the length of alkyl group.

Estimation of the vibration fatigue of a linear elastic system based on a desiign sensitivity analysis (설계 만감도 해석을 활용한 선형 시스템 진동내구 평가)

  • Kim, Chan-Jung;Kim, Ku-Sik;Kang, Ho-Young;Jin, Yeo-Hwa;Lee, Bong-Hyun
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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    • 2010.10a
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    • pp.491-496
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    • 2010
  • The direct design modification of problematic component is disallowed in order to sacrifice other major factors such as a stability or a major performance. So, the best design policy is to risvise the immature structural medchanism under the minimal design change as soon as possible. For this paper presents a new design sensitivity analysis based on transmissibility rtio (TR) of response acceleration to find a proper candidate for the minimal design modification. The new sensitivity analysis is based on the fact that the sensitivity of TR over a small design change is inversly proportinal to the magnitude of TR. The theory of proposed design sensitivity analysis is simulated with the variance of TR over a dynamic change. Then, new methodology is appplied for a linear elastic specimen to detect the most sensitive node over a design change using measured accleration data during uni-axial vibration test, The physical verification of the sensitivity method is conducted on the CAE model of a linear elastic specimen by adding concentration mass and the vibration fatigue of the simple specimen is analyzed to estimate the relationship between fatigue behaviors and sensitivity consequences.

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Study of physical simulation of electrochemical modification of clayey rock

  • Chai, Zhaoyun;Zhang, Yatiao;Scheuermann, Alexander
    • Geomechanics and Engineering
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    • v.11 no.2
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    • pp.197-209
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    • 2016
  • Clayey rock has large clay mineral content. When in contact with water, this expands considerably and may present a significant hazard to the stability of the rock in geotechnical engineering applications. This is particularly important in the present work, which focused on mitigating some unwelcomed properties of clayey rock. Changes in its physical properties were simulated by subjecting the rock to a low voltage direct current (DC) using copper, steel and aluminum electrodes. The modified mechanism of the coupled electrical and chemical fields acting on the clayey rock was analyzed. It was concluded that the essence of clayey rock electrochemical modification is the electrokinetic effect of the DC field, together with the coupled hydraulic and electrical potential gradients in fine-grained clayey rock, including ion migration, electrophoresis and electro-osmosis. The aluminum cathodes were corroded and generated gibbsite at the anode; the steel and copper cathodes showed no obvious change. The electrical resistivity and uniaxial compressive strength (UCS) of the modified specimens from the anode, intermediate and cathode zones tended to decrease. Samples taken from these zones showed a positive correlation between electric resistivity and UCS.