• Title/Summary/Keyword: progressive development

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Inhibitory Effects of (-)-Epigallocatechin gallate on Morphine-Induced Locomotor Sensitization and Conditioned Place Preference in Mice

  • Eun, Jae-Soon;Kwon, Han-Na;Hong, Jin-Tae;Oh, Ki-Wan
    • Biomolecules & Therapeutics
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    • v.14 no.3
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    • pp.125-131
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    • 2006
  • The inhibitory effects of (-)-epigallocatechin gallate (EGCG), a major compound of green tea, on the development of locomotor sensitization, conditioned place preference (CPP) and dopamine receptor supersensitivity induced by the repeated administration of morphine were investigated in mice. A single administration of morphine produces hyperlocomotion. The repeated administration of morphine develops sensitization, a progressive enhancement of locomotion, which is used as a model for studying the craving and drug-seeking behaviors characterizing addiction, and CPP, which is used as a model for studying drug reinforcement, respectively. EGCG inhibited morphine-induced hyperlocomotion, sensitization and CPP. In addition, EGCG inhibited the development of postsynaptic dopamine receptors supersensitivity, which may be an underlying common mechanism that mediates the morphine-induced dopaminergic behaviors such as sensitization and CPP. Apomorphine (a dopamine agonist)-induced climbing behaviors also were inhibited by a single direct administration of EGCG These results provide evidence that EGCG has anti-dopaminergic activity, as inhibiting the development of dopamine receptor supersensitivity and apomorphine-induced climbing behaviors. Therefore, it is suggested that green tea may be useful for the prevention and therapy of these adverse actions of morphine.

Embryonic Development of Siberian Sturgeon Acipenser baerii under Hatchery Conditions: An Image Guide with Embryological Descriptions

  • Park, Chulhong;Lee, Sang Yoon;Kim, Dong Soo;Nam, Yoon Kwon
    • Fisheries and Aquatic Sciences
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    • v.16 no.1
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    • pp.15-23
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    • 2013
  • Normal embryonic development at a constant temperature ($18^{\circ}C$) has been described for the Siberian sturgeon Acipenser baerii (Acipenseriformes). Hormone-induced spawning and artificial insemination were performed to prepare embryonic batches for embryologic examination. After insemination, early cleavages of the Siberian sturgeon embryos continued for 7 h post-fertilization (HPF), showing the typical pattern of uneven holoblastic cleavage. Blastulation and gastrulation began at 9 HPF and 19 HPF, respectively. Epiboly formation (2/3 covered) was observed at 25 HPF during gastrulation. Neurulation was initiated with the formation of a slit-like neural groove from the blastopore at 33 HPF. During neurulation, the primary embryonic kidney (pronephros) and s-shaped heart developed. The embryos underwent progressive differentiation, which is typical of Acipenseriform species. A mass hatching was observed at 130 HPF, and the average total length of the hatched prolarvae was 10.5 mm. The hatched prolarvae possessed a typical pigment plug (yolk plug). The results of this study are valuable not only as a reference guide for the artificial propagation of Siberian sturgeon in hatcheries but also as the basis for the derivation of developmental gene expression assays for this species.

Ligand-Based CoMFA Study on Pyridylpyrazolopyridine Derivatives as PKCθ Kinase Inhibitors

  • Balasubramanian, Pavithra K.;Balupuri, Anand;Cho, Seung Joo
    • Journal of Integrative Natural Science
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    • v.7 no.4
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    • pp.253-259
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    • 2014
  • Protein kinase C theta (PKC-${\theta}$) is a serine/threonine specific protein kinase. It is largely expressed in the T-cells and CD28 signaling. PKC-${\theta}$ phosphorylates diverse proteins that are involved in the various cellular signaling pathways. Activated PKC-${\theta}$ in turn activates other transcription factors that control the proliferation and differentiation of T- cells. PKC-${\theta}$ is considered to be an interesting therapeutic target due to its crucial role in the proliferation, differentiation and survival of T-cells. In the present study, we have performed ligand-based CoMFA study on a series of pyridylpyrazolopyridine derivatives as PKC-${\theta}$ inhibitors. An acceptable CoMFA model ($q^2$=0.544; ONC=4; $r^2$=0.876) was developed and validated by Bootsrapping and progressive sampling. The CoMFA contour map suggested the regions to increase the activity. Bulky substitutions in R2 position of the piperizine ring could increase the activity. Similarly positive, small substitution in the R1 position of the Pyridine ring could considerably increase the activity. Our work could assist in designing more potent PKC-${\theta}$ inhibitors of pyridylpyrazolopyridine derivatives.

Refashioning Cities in the Middle East: The Case of Dubai

  • Kheir Al-Kodmany
    • International Journal of High-Rise Buildings
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    • v.13 no.1
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    • pp.11-32
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    • 2024
  • In recent years, urban landscapes across the globe have undergone a remarkable transformation marked by a substantial surge in skyscraper development. This paper offers a comprehensive overview of the contemporary evolution of tall buildings, with a particular emphasis on the Middle East. It surveys tall building development in the ten "tallest cities" across the Middle East, including Dubai, Doha, Abu Dhabi, Sharjah, Riyadh, Manama, Tel Aviv, Kuwait, Mecca, and Jeddah, while listing the tallest ten buildings in each city. The focus sharpens on Dubai, UAE, serving as a compelling case study that vividly illustrates the city's swift metamorphosis from a low-rise to a high-rise urban center. Through meticulous examination, the study aims to unveil the key drivers propelling the construction of the world's tallest buildings, asserting that globalization factors play a pivotal role in fostering this transformative shift. The impetus behind this surge is rooted in the aspiration to project a modern and progressive image on the global stage. With Dubai at the forefront, cities in the Middle East strategically endeavor to reshape their international image and reclaim historical grandeur through ambitious skyscraper projects.

Development of Progressive Die CAD/CAM System for Manufacturing Lead Frame, Semiconductor (반도체 리드 프레임 제조를 위한 프로그레시브 금형의 CAD/CAM 시스템 개발)

  • Choi, J.-C.;Kim, B.-M.;Kim, C.;Kim, J.-H.;Kim, C.-B.
    • Journal of the Korean Society for Precision Engineering
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    • v.16 no.12
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    • pp.230-238
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    • 1999
  • This paper describes a research work of developing computer-aided design of lead frame, semiconductor, with blanking operation which is very precise for progressive working. Approach to the system is based on the knowledge-based rules. Knowledge for the system is formulated from plasticity theories, experimental results and the empirical knowledge of field experts. This system has been written in AutoLISP on the AutoCAD using a personal computer and in I-DEAS Drafting Programming Language on the I-DEAS Master Series Drafting with Workstation, HP9000/715(64) and tool kit on the ESPRIT. Transference of data among AutoCAD, I-DEAS Master Series Drafting, and ESPRIT is accomplished by DXF(drawing exchange format) and IGES(initial graphics exchange specification) methods. This system is composed of six modules, which are input and shape treatment, production feasibility check, strip-layout, die-layout, modelling, and post-processor modules. The system can design process planning and Die design considering several factors and generate NC data automatically according to drawings of die-layout module. As forming process of high precision product and die design system using 2-D geometry recognition are integrated with technology of process planning, die design, and CAE analysis, standardization of die part in die design and process planning of high pression product for semiconductor lead frame is possible to set. Results carried out in each module will provide efficiencies to the designer and the manufacturer of lead frame, semiconductor.

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Genetic and Molecular Mechanisms in the Neuronal Ceroid-Lipofuscinoses (유전질환 신경 세로이드 리포푸신증들에 대한 고찰)

  • Lee, Min-Young;Kim, Dong-Hyun;Yoon, Dong-Ho;Kim, Han-Bok;Park, Joo-Hoon;Lee, Hwan-Myoung;Kim, Sung-Hoon;Kim, Sung-Jo
    • Development and Reproduction
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    • v.13 no.2
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    • pp.63-77
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    • 2009
  • The neuronal ceroid-lipofuscinoses (NCLs) are a kind of neurodegenerative storage disorders. The NCLs are charecterizated by accumulation of autofluorescent lipofuscin or lipopigment in the brain. All NCL group belongs to in lysosomal storage disorders (LSDs), except Northern epilepsy. NCLs are the most common group of progressive neurodegenerative disorders in childhood, with an incidence as high as I in 12,500 live births. Four main clinical types have been described based on the onset age : infantile, late infantile, juvenile and adult types. Clinical symptoms of NCLs include loss of vision, seizures, epilepsy, progressive mental retardation and a premature death. Although mutation causes neurodegeneration in NCLs, the molecular mechanism by which mutation leads to neurodegeneration remains unclear. In this paper, we review the characteristics of these NCLs.

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The Response of Sea Levels to Typhoons in the Japan Sea -Part I. The Response on the North Japanese Coast- (동해연안역 해수면변동에 미치는 태풍의 영향 -I. 일본 북부연안에서의 해수면변동-)

  • HONG Chol-Hoon;YOON Jong-Hwan
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.6
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    • pp.567-579
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    • 1993
  • The response of sea levels to a typhoon in the north Japanese coast in the Japan Sea is investigated by using hourly ses level data($1966{\sim}1986$) and a numerical shallow water model with high resolution($5'{\times}5'$). The observed sea level analysis shows (1) progressive waves exist between Simonoseki(SS) and Maizuru(MZ) with the mean phase speed of about 4 m/s during the passage of the typhoon, (2) the phase speed between Sasebo(SB) and HK(Hakata) is slower(about 1.7 m/s), and (3) the maximum sea level at HK is achieved about 0.5 day later than that of SS. In many aspects, the numerical model results correspond well to the above observed features. In the model the progressive waves are identified as a topographic wave with the phase speed of about 4 m/s. Before the typhoon passes through the Korea Strait/ the Tsushima Strait, the wave propagations along the Japanese coast are significantly influenced by the southwestward coastal jet induced by the wind stress parallel to the coast. The waves start to propagate northeastward along the coast when the coastal jet is weakened.

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Strength Prediction on Composite Laminates Including Material Nonlinearity and Continuum Damage Mechanics (재료 비선형과 연속체 손상역학을 고려한 복합 적층판의 강도 예측)

  • Park, Kook-Jin;Kang, Hee-Jin;Shin, Sangjoon;Choi, Ik-Hyun;Kim, Minki;Kim, Seung-Jo
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.42 no.11
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    • pp.927-936
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    • 2014
  • This paper presents development and verification of the progressive failure analysis upon the composite laminates. Strength and stiffness of the fiber-reinforced composite are analyzed by property degradation approach with emphasis on the material nonlinearity and continuum damage mechanics (CDM). Longitudinal and transverse tensile modes derived from Hashin's failure criterion are used to predict the thresholds for damage initiation and growth. The modified Newton-Raphson iterative procedure is implemented for determining nonlinear elastic and viscoelastic constitutive relations. Laminar properties of the composite are obtained by experiments. Prediction on the un-notched tensile (UNT) specimen is performed under the laminate level. Stress-strain curves and strength results are compared with the experimental measurement. It is concluded that the present nonlinear CDM approach is capable of predicting the strength and stiffness more accurately than the corresponding linear CDM one does.

A Study on the One Side Freezing /Thaw and Carbonation of Autoclaved Lightweight Concrete (경량기포콘크리트의 편면동결융해 및 탄산화에 관한 연구)

  • 노재성;황의환;홍성수;이범재
    • Magazine of the Korea Concrete Institute
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    • v.7 no.4
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    • pp.149-156
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    • 1995
  • The fracture process zone in concrete is a region ahead of a traction-free crack, in which two major mechanisms, microcracking and bridging, play important roles. The toughness due to bridging is dominant compared to toughness induced by microcracking, so that the bridging is dominani: mechanism governing the fracture process of concrete. Fracture mechanics does work for concrete provided that the fracture process zone is being considered, so that the development of model for the fracture process zone is most important to describe fracture phenomena in concrete. In this paper the bridging zone, which is a part of extended rnacrocrack with stresses transmitted by aggregates in concrete, is modelled by a Dugdale-Barenblatt type model with linear tension-softening curve. Two finite element techniques are shown for the analysis of progressive cracking in concrete based on the discrete crack approach: one with crack element, the other without crack element. The advantage of the technique with crack element is that it dees not need to update the mesh topology to follow the progressive cracking. Numerical results by the techniques are demonstrated.

Test and Finite Element Analysis on Compression after Impact Strength for Laminated Composite Structures of Unidirectional CFRP (일방향 탄소섬유강화 플라스틱 복합재 적층구조의 충격 후 압축강도 시험 및 유한요소해석)

  • Ha, Jae-Seok
    • Composites Research
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    • v.29 no.6
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    • pp.321-327
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    • 2016
  • In this study, tests and finite element analyses were performed regarding compression after impact strength for laminated composite structures of unidirectional carbon fiber reinforced plastic widely used in structural materials. Two lay-up sequences of composite laminates were selected as test specimens and four impact energy conditions were applied respectively. Impact and compressive strength tests were conducted in accordance with ASTM standards. Impact damages in test specimens were analyzed by using non-destructive inspection method of C-Scan, and compression after impact strengths were calculated with compressive test results. Progressive failure analysis method that can progressively simulate damages and fractures of fiber/matrix/lamina/laminate level was used for impact and compressive strength analyses. All analysis results including contact force, deflection, impact damages, compressive strengths, etc. were compared to test results, and the validity of analysis method was verified.