• Journal of Plant Biology
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• v.37 no.1
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• pp.27-36
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• 1994

For establishing a transformation system of rice, an efficient introduction of foreign genes into embryogenic cell suspension by particle bombardment was conducted. The particle inflow gun based on the acceleration of DNA-coated tungsten particles using pressurized helium was constructed for delivery of DNA into rice cells. Several bombardment parameters were optimized using the transient expression of GUS gene. The conditions that gave the highest GUS gene expression of about 1000 blue spots per g fresh weight of bombarded cells include treatment of the cells with 0.5 M osmotic pressure, and use of the 410 kPa helium, 110 mm target distance, 13 mm syringe filter holder and 5 $\mu$L DNA/tungsten mixtures. It was also confirmed that rice actin promoter-intron construct gave the highest expression of all promoter-sequences studied. Eight weeks after the bombardment, stably transformed calluses were obtained on the selection medium containing 100 mg/L G418 and showed the strong activity in in situ GUS assay.

• Applied Science and Convergence Technology
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• v.23 no.1
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• pp.34-39
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• 2014

The programmable switches which control the delivery of electrical signals in programmable logic devices are fabricated using memory technology. Although phase change memory (PCM) technology is one of the most promising candidates for the manufacturing of the programmable switches, the threshold switching material should be added to a PCM cell for realization of the programmable switches based on PCM technology. In this work, we report the impurity-doped $Ge_2Sb_2Te_5$ (GST) chalcogenide alloy exhibiting threshold switching property. Unlike the GST thin film, the doped GST thin film prepared by the incorporation of In and P into GST is not crystallized even at the postannealing temperature higher than $200^{\circ}C$. This specific crystallization behavior in the doped GST thin film is attributed to the stabilization of the amorphous phase of GST by In and P doping.

• Journal of Environmental Health Sciences
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• v.26 no.2
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• pp.91-96
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• 2000

We investigated characters of transdermal therapeutic system(TTS) and the skin permeability of that with applying drug delivery system(DDS). Natural gums were selected as material of TTS. The permeation of natural gums ointment containing drug in rat skin using diffusion cell model. Permeation properties of materials were investigated for water soluble drug such as riboflavin in vitro. We used glycerin, PEG 600 and oleic acid as enhancers. Since dermis has more hydration than the stratum corneum, skin permeation rate at steady state was highly influenced when glycerin was used in riboflavin. The permeation rate of content enhancer and drug was found to be faster than that of content riboflavin only. These results showed that skin permeation rate of drug across the composite was mainly dependent on the property of ointment base and drug. All the gum ointment tested showed good safety. Proper selection of the materials which resemble and enhance properties of the delivering drug was found to be important in controlling the skin permeation rate.

• Journal of Pharmaceutical Investigation
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• v.29 no.3
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• pp.185-191
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• 1999

The polymeric films containing drug and various excipients were fabricated using aqueous-based $Eudragit^{\circledR}$ RS 30D dispersions. The diffusional behaviors and mechanism of the fabricated polymeric film were investigated using Keshary-Chien diffusion cell. The melatonin was used as a model drug. The diffusion behaviors of drug through the fabricated polymeric films were highly dependent on drug concentration in donor part, polymer contents and drug concentration, and the types of plasticizers and solubilizers. The fabricated polymeric films containing excipients and solubilizers could be applied for the controlled release of poorly water-soluble drug and for the preparation of drug-containing latex films for topical or oral drug delivery.

• Journal of Information Processing Systems
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• v.11 no.4
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• pp.616-629
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• 2015

A mobile terminal will expect a number of handoffs within its call duration. In the event of a mobile call, when a mobile node moves from one cell to another, it should connect to another access point within its range. In case there is a lack of support of its own network, it must changeover to another base station. In the event of moving on to another network, quality of service parameters need to be considered. In our study we have used the Markov decision process approach for a seamless handoff as it gives the optimum results for selecting a network when compared to other multiple attribute decision making processes. We have used the network cost function for selecting the network for handoff and the connection reward function, which is based on the values of the quality of service parameters. We have also examined the constant bit rate and transmission control protocol packet delivery ratio. We used the policy iteration algorithm for determining the optimal policy. Our enhanced handoff algorithm outperforms other previous multiple attribute decision making methods.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.11
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• pp.5323-5343
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• 2018

Mobile applications and social networks tend to enhance the need for high-quality content access. To address the rapid growing demand for data services in mobile networks, it is necessary to develop efficient content caching and distribution techniques, aiming at significantly reduction of redundant content transmission and thus improve content delivery efficiency. In this article, we develop optimal cooperative content cache and distribution policy, where a geographical cluster model is designed for content retrieval across the collaborative small cell base stations (SBSs) and replacement of cache framework. Furthermore, we divide the SBS storage space into two equal parts: the first is local, the other is global content cache. We propose an algorithm to minimize the content caching delay, transmission cost and backhaul bottleneck at the edge of networks. Simulation results indicates that the proposed neighbor SBSs cooperative caching scheme brings a substantial improvement regarding content availability and cache storage capacity at the edge of networks in comparison with the current conventional cache placement approaches.

• Mycobiology
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• v.49 no.2
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• pp.95-104
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• 2021

Species of the genus Aspergillus have a variety of effects on humans and have been considered industrial cell factories due to their prominent ability for manufacturing several products such as heterologous proteins, secondary metabolites, and organic acids. Scientists are trying to improve fungal strains and re-design metabolic processes through advanced genetic manipulation techniques and gene delivery systems to enhance their industrial efficiency and utility. In this review, we describe the current status of the genetic manipulation techniques and transformation methods for species of the genus Aspergillus. The host strains, selective markers, and experimental materials required for the genetic manipulation and fungal transformation are described in detail. Furthermore, the advantages and disadvantages of these techniques are described.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.168.3-169
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• 2003

The matrix metalloproteases (MMPs) play important roles in invasion, metastasis and angiogenesis in various cell types. Tissue inhibitor of metalloprotease (TIMP)-2, an endogenopus inhibitor of MMP-2, has been shown to inhibit invasion and metastasis. We have previously shown that MMP-2 is responsible for the H-ras-induced invasive and migrative phenotypes in MCF10A human breast epithelial cells. Here, we investigated the effect of TlMP-2 overexpression on invasion and migration in H-ras MCF10A cells. (omitted)

• Journal of Industrial Technology
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• v.42 no.1
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• pp.29-36
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• 2022

The CRISPR system has revolutionized gene editing field. Cas9-mediated gene editing such as Indel induction or HDR enable targeted gene disruption or precise correction of mutation. Moreover, CRISPR-based new editing tools have been developed such as base editors. In this review, we focus on gene editing in human pluripotent stem cells, which is principal technique for gene correction therapy and disease modeling. Pluripotent stem cell-specific drug YM155 enabled selection of target gene-edited pluripotent stem cells. Also, we discussed base editing for treatment of congenital retina disease. Adenine base editor delivery as RNP form provide an approach for genetic disease treatment with safe and precise in vivo gene correction.

• IMMUNE NETWORK
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• v.11 no.3
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• pp.163-168
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• 2011

Background: Nanoparticles (NPs) prepared from biodegradable polymers, such as poly (D,L-lactic acid-co-glycolic acid) (PLGA), have been studied as vehicles for the delivery of antigens to phagocytes. This paper describes the preparation of antigen-loaded PLGA-NPs for efficient cross-priming. Methods: NPs containing a similar amount of ovalbumin (OVA) but different sizes were produced using a micromixer-based W/O/W solvent evaporation procedure, and the efficiency of the NPs to induce the cross-presentation of OVA peptides were examined in dendritic cells (DCs). Cellular uptake and biodistribution studies were performed using fluorescein isothiocyanate (FITC)-loaded NPs in mice. Results: The NPs in the range of $1.1{\sim}1.4{\mu}m$ in size were the most and almost equally efficient in inducing the cross-presentation of OVA peptides via $H-2K^b$ molecules. Cellular uptake and biodistribution studies showed that opsonization of the NPs with mouse IgG greatly increased the percentage of FITC-positive cells in the spleen and lymph nodes. The major cell type of FITC-positive cells in the spleen was macrophages, whereas that of lymph nodes was DCs. Conclusion: These results show that IgG-opsonized PLGA-NPs with a mean size of $1.1{\mu}m$ would be the choice of biodegradable carriers for the targeted-delivery of protein antigens for cross-priming in vivo.