• Polymer(Korea)
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• v.38 no.4
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• pp.477-483
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• 2014

Poly(lactic acid) (PLA) and poly(${\varepsilon}$-caprolactone) (PCL) blends with various components for melt-blown non-wovens were prepared by a twin-screw extruder. Tributyl citrate (TBC) was added in order to improve the miscibility between PLA and PCL. The results showed that small circular particles of PCL were dispersed in PLA matrix uniformly. The addition of PCL had the heterogeneous nucleation effect on the crystallization of PLA and decreased thermal stability of PLA. The flow of pure PLA and blends approached to Newtonian liquid at a low shear rate and expressed more obvious viscoelasticity at a high shear rate.

• Journal of Ecology and Environment
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• v.29 no.2
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• pp.175-183
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• 2006

The discovery of deep-sea hydrothermal vents and their ecosystems is a monumental landmark in the history of Ocean Sciences. Deep-sea hydrothermal vents are scattered along the global mid-ocean ridges and back-arc basins. Under sea volcanic phenomena related to underlying magma activities along mid-ocean ridges generate extreme habitats for highly specialized communities of animals. Multidisciplinary research efforts during past three decades since the first discovery of hydrothermal vents along the Galapagos Rift in 1977 revealed fundamental components of physiology, ecology, and evolution of specialized vent communities of micro and macro fauna. Heterogeneous regional geological settings and tectonic plate history have been considered as important geophysical and evolutionary factors for current patterns of taxonomic composition and distribution of vent faunas among venting sites in the World Ocean basins. It was found that these communities are based on primary production of chemosynthetic bacteria which directly utilize reduced compounds, mostly $H_2S$ and $CH_4$, mixed in vent fluids. Symbioses between these bacteria and their hosts, vent invertebrates, are foundation of the vent ecosystem. Gene flow and population genetic studies in parallel with larval biology began to unveil hidden dispersal barrier under deep sea as well as various dispersal characteristics cross taxa. Comparative molecular phylogenetics of vent animals revealed that vent faunas are closely related to those of cold-water seeps in general. In perspective additional interesting discoveries are anticipated particularly with further refined and expanded studies aided by new instrumental technologies.

• Journal of Genetic Medicine
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• v.10 no.1
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• pp.1-6
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• 2013

Chronic granulomatous disease (CGD) is a rare inherited disorder of a defective NADPH oxidase enzyme, resulting in very low or no production of superoxide and subsequent reactive oxygen species. Consequently, patients with CGD are highly susceptible to severe bacterial and fungal infections. CGD is a genetically heterogeneous disease caused by defects in any one of the genes encoding the NADPH oxidase components. CGD generally affects about 3-4 per 1,000,000 individuals; thus, it is surprising that the prevalence of CGD on Jeju Island is 34.3 per 1,000,000 individuals. At present, 20 patients with CGD from 14 unrelated families on Jeju Island have been identified; nine males and 11 females. All patients with CGD tested on Jeju Island had an identical and homozygous mutation (c.7C>T in CYBA, p.Q3X in $p22^{phox}$). Therefore, all patients were autosomal recessive form of CGD. This strongly suggests that the unique and identical mutation in CYBA may be inherited from a common proband. Using mutation-specific primers to detect the mutated allele in CYBA, the frequency of subjects carrying a mutated allele was 1.3% of enrolled subjects from Seogwipo City. Further studies are necessary to elucidate how frequently this mutant allele occurs in the population on Jeju Island. Additionally, it is important to construct a national registry system to understand the pathophysiology of CGD and develop a strategy for long-term therapy.

• Mycobiology
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• v.29 no.1
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• pp.15-18
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• 2001

Protoplast fusion is a useful technique for establishing fungal hybrids to overcome the natural barriers. The ultrastructure of protoplast and its fusion process were observed using a scanning electron microscopy(SEM) and a transmission electron microscopy(TEM). The protoplasts were variable in size from $0.5{\sim}15{\mu}m$ in diameter, and the mean diameter was about $3{\sim}5{\mu}m$. It was impossible to discriminate protoplasts of Lentinula edodes from protoplasts of Coriolus versicolor by size and surface structure. Big aggregates of the dehydrated protoplasts were observed, after polyethylene glycol 4000 treatment. Nucleus, mitochondria, lipid granules and various vesicles having granules were scattered in the cytoplasm. The vesicles were heterogeneous in size and vary from one protoplast to another. The fused membrane layer of the two protoplasts was observed. Time protoplast membrane contact and reorganization of membrane components were essential condition for protoplast fusion. Transmission electron micrograph showed fused protoplasts and flattening of the cells in the area of the membrane contact. We hope that our electron microscopic observations provide some insights into the understanding of the fusion process of protoplast in fungi.

• The Transactions of the Korea Information Processing Society
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• v.6 no.8
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• pp.2088-2097
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• 1999

We propose the software framework construction method that increases reusability through use case extraction and structuring of software system's dynamic behavior of which identifying behavior patterns from software domain models. Most behavior models do not provide a consistent modeling technique for harmonizing user's heterogeneous requirements, and not yet prepared to a detailed optimizing technique for redevelopment and maintenance. Therefore, we need a software reuse framework to support consistency and reusability of existing development models using use cases with functional characteristics. a lattice model is used to this approach for structuring use cases, and the reuse process that can be driven to reusable components is introduced in this paper,.

• Analytical Science and Technology
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• v.8 no.4
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• pp.1079-1087
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• 1995

The quality of human life is directly related to the quality of the environment. To assess environmental quality we must first determine the MCLG(Maximum Contaminant Level Goal), MCL(Maximum Contaminant Level), environmental impact and so on. The MCLG is the concentration at which no known adverse health effects occur. The MCLG is determined by risk assessment identifying which process is hazardous assessing, dose-response, human exposure, and characteristics of risk. With consideration of analytical methods, treatment technology, cost and regulatory impact, the MCL is set as close to the MCLG as possible. In this way, determination of the concentration and national distribution of contaminants is important for assessment of environmental quality The analytical sciences pose potential problems in assessing environmental quality. Continuing improvement in the performance of analytical instruments and operating technique has been lowering the limits of detectability. Contaminant concentration below the detection limit has usually been reported as ND(Not-Detected) and this has often been misunderstood as equivalent to zero. Because of this, more the contaminant concentration in the past was below the detection limit, whereas contaminants can be quantified now even though the contaminant concentration might remain the same or may even have decreased. In addition, environmental sampling has various components due to heterogeneous matrices. These samples are used to overestimate the concentration of the contaminant due to large variability, resulting in excess readings for MCL. In this paper, the significance of the analytical sciences is emphasized in both a conceptual and a technical approach to environmental assessment.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.4 no.5
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• pp.836-858
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• 2010

Web Services allow a user to integrate applications from different platforms and languages. Since mobile applications often run on heterogeneous platforms and conditions, Web Service becomes a popular solution for integrating with server applications. However, because of its verbosity, XML based SOAP messaging gives the possible overhead to the less powerful mobile devices. Based on the mobile client's behavior that it usually exchanges messages with Web Service continuously in a session, we design the Handheld Flexible Representation architecture. Our proposed architecture consists of three main components: optimizing message representation by using a data format language (Simple_DFDL), streaming communication channel to reduce latency and the Context-store to store context information of a session as well as redundant parts of the messages. In this paper, we focus on the Context-store and describe the architecture with the Context-store for improving the performance of mobile Web Service messaging. We verify our approach by conducting various evaluations and investigate the performance and scalability of the proposed architecture. The empirical results show that we save 40% of transit time between a client and a service by reducing the message size. In contrast to solutions for a single problem such as the compression or binarization, our architecture addresses the problem at a system level. Thus, by using the Context-store, we expect reliable recovery from the fault condition and enhancing interoperability as well as improving the messaging performance.

• Journal of Communications and Networks
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• v.4 no.4
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• pp.336-343
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• 2002

A major challenge for next generation mobile communication is capturing the system architecture’s complexity with all its internal and external dependencies. Seamless integration of heterogeneous environments in all system parts is a key requirement. Moreover, future systems have to consider the different evolution cycles of individual system parts. Among those, services are expected to change the fastest. With respect to these considerations, we propose an overall architecture for next generation mobile communication systems. It covers all system parts from wireless transmission to applications including network and middleware platform. Our approach focuses on adaptability in terms of recon- figurability and programmability to support unanticipated system evolution. Therefore, we consider abstraction layers which consist of adaptable cooperating components grouped by open platforms rather than rigid system layers. In addition to that, we introduce cross-layer cooperation allowing an efficient use of the available resources. Specific scenarios illustrate the feasibility of our approach.

• Journal of the Korea Society of Computer and Information
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• v.5 no.2
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• pp.37-42
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• 2000

Object technologies like the OMG's CORBA are enabling technologies the aim to facilitate integration implementation of diverse software components in distributed. heterogeneous environment. CORBA and similar object integration technologies define a standard component interconnection and inter-operation model , promote object-oriented principles to encapsulate incompatible component implementations. In this Paper. we present a connector model for software architectural representation of complex component collaborations. Our Connector model is base on research in software achitecture and object-oriented modeling. and part of a design framework for modeling component-based system. We believe the connector concepts to be vary benificial for a clear expression of dependencies between multiple component in Java Bean-based system.

• Journal of Genetic Medicine
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• v.15 no.1
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• pp.24-27
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• 2018

Cornelia de Lange syndrome (CdLS) is a rare, clinically and genetically heterogeneous, multi-system developmental disorder caused by mutations in genes that encode components of the cohesin complex. X-linked CdLS caused by an SMC1A mutation is an extremely rare disease characterized by phenotypes milder than those of classic CdLS. In the Republic of Korea, based on a literature review, one family with SMC1A-related CdLS with mild phenotypes has been genetically confirmed to date. In this study, we describe the clinical features of a Korean boy with a hemizygous novel missense mutation and his mother with a heterozygous mutation, i.e., c.2447G>A (p.Arg816His) in SMC1A, identified by multi-gene panel sequencing. The proband had a mild phenotype with typical facial features and his mother exhibited a mild, subclinical phenotype. This study expands the clinical spectrum of patients with X-linked CdLS caused by SMC1A variants. Moreover, these findings reinforce the notion that a dominant negative effect in a carrier female with a heterozygous mutation in SMC1A results in a phenotype milder than that in a male patient with the same mutation.