• Journal of Technology Innovation
• /
• v.13 no.2
• /
• pp.71-95
• /
• 2005

This study aims to explore and understand the role of return migrants in the regional innovation system of a transition economy (China) by analyzing the activities of returning entrepreneurs in two emerging high-tech industries in Shanghai. The empirical analysis is based on in-depth interviews with founders of high-tech companies and experts in Shanghai. The results of the analysis reveal that return migrants are a significant factor for the Shanghai innovation system, which is presently in a transition from a former manufacturing site to a metropolitan region comprising a range of industries (including high-tech) and services. First of all, return migrants are important for the Shanghai RIS in terms of numbers. Second, they engage in activities in the medium range of high-tech which reflects prevailing weaknesses of the framework conditions for innovation in Shanghai. However, due to their international background, returning entrepreneurs are able to overcome these weaknesses, and thus contribute to the development of high-tech industries in Shanghai and to a reduction of the technological lock-in.

• International Journal of Air-Conditioning and Refrigeration
• /
• v.8 no.1
• /
• pp.29-39
• /
• 2000

A series of tests were performed to verify the transient characteristics of heat pump in heating and cooling mode when operating speed was varied over the 30 to 102Hz. One of the major issues that has not been addressed so far is transient characteristics during speed modulation. The model for cycle simulation has been developed to predict the cycle performance under conditions of decreasing drive frequency and the results of the theoretical study were compared with the results of the experimental study. The simulated results were in good agreement with the experimental result within 10%. The transient cycle migration of the liquid state refrigerant causes significant dynamic change in system. Thus, the migration of refrigerant was the most important factor whenever do experimental results analysis or develop simulation model.

• SUVANNABHUMI
• /
• v.12 no.2
• /
• pp.81-118
• /
• 2020

Despite its centrality at a pivotal crossroads of both land and sea of East-West trade, communications and travel, the region now known as Southeast Asia provides very few scholarly works situating or featuring it in an international context. Because of this paucity, there is immense scope for exploration. But prior to further explorations, justification is needed to establish that Southeast Asia, as a region, is a subject of interest, relevance, and significance in a global context. Southeast Asia was home to several empires whose reach transcended the region and beyond. Southeast Asia in, and as part of international history as an area of study is therefore justifiable. Moreover, other factors come into play, viz. geography, resources, migration, diffusion of ideas and beliefs from without and accommodation from within, shared experience of imperialism and colonialism, decolonization, and the Cold War, and the collective fate under the Association of Southeast Asian Nations (ASEAN), that further bolster its rationalization as a component of international history. Explorations, on the other hand, examine issues and obstacles that contribute to the paucity of works on Southeast Asia in international history. Furthermore, in contextualizing Southeast Asia in international history, there might appear challenges that need to be identified, confronted, and resolved.

• Strategy21
• /
• s.30
• /
• pp.263-285
• /
• 2012

History, demonstrating convincingly that pirates have arisen continuously for a lengthy period of time throughout the world, is able to become a cooperative study of international law in terms of pirates matters ; Viking pirates. There are beneficial topics for the study of true nature of viking activities and the settlement of present pirates matters ; How were the pirates activities of Vikings, What sort of relations do they have between Vikings and other pirates which have arisen in world history, What are the differences compared to present concept of pirates. There were active pirates activities in the coast and waters of Scandinavia even before the period of the Migration Age because of geographical condition. With those experiences, Vikings began to ambush Britain Islands sailing across the North Sea since the late 8C, ages of migration in earnest. They ambushed all coasts of the European Continent expending boundary until the late of 11C. Pirate activities in a sort of guerrilla operations were operated when they encountered Islams in the Iberian Peninsula and the coast of North Africa. They showed twofold attitudes ; if the defence of the region and sea was weak, they plundered, or if strong, traded. In plundered europeans' position, Vikings were pirates with cruelty and barbarians. In vikings position, they were normal human beings who did a pirate activity to lead a better life. Viking pirates showed different characteristics in terms of three aspects ; area and aspect of action, activity after piracy. Meanwhile, Viking pirates showed several differences with pirates defined in terms of modern international law. Among the satisfying conditions of pirates, required by the international law of the sea, Vikings fulfilled animus furandi, desire for gain, activities for hatred and revenge, and private ends. Other conditions including attacking authority of the vessels, activities toward private ships, activities in the coast and the land, and illegal terroristic activities toward ships are found in viking pirates. However, Viking pirates do not show the activities in high seas and in the outside of a State's jurisdiction. In addition, it cannot be excluded that they pirated with vessels of regional leaders and the Sovereign, not private ships. Contrary to the definition of concept in terms of modern international law toward pirates, Viking invaded foreign waters, came on shore to foreign land and island, went up-stream the rivers to the back of interior, and attacked churches and abbeys. Strangely, they sometimes settled down in the places where they had pirated. Today, pirates appearing in history and defined in international law exist simultaneously and separately. It means, the historical nature and the nature under the international law are turning up differently. Historical cases of pirates should be reflected to modern international law. If so, it seems that the clue to solve pirate problems can be arranged. History is the immortal living thing, which not just existed as a past but reflects present.

• International Journal of Oral Biology
• /
• v.41 no.4
• /
• pp.217-223
• /
• 2016

Porphyromonas gingivalis, a foremost periodontal pathogen, has been known to cause periodontal diseases. Epidemiologic evidences have indicated the involvement of P. gingivalis in the development of cardiovascular diseases. In this study, we show that the P. gingivalis lipopolysaccharide increases the mRNA expression and protein secretion of interleukin-6 in vascular smooth muscle cells. We demonstrate that P. gingivalis LPS activates the extracellular signal-regulated kinase 1/2 (ERK1/2), p38 mitogen-activated protein kinase (MAPK), and Akt, which mediate the IL-6 expression in vascular smooth muscle cells. Also, P. gingivalis LPS stimulates the vascular smooth muscle cell migration, which is a critical step for the progression of atherosclerosis. Moreover, neutralization of the IL-6 function inhibits the migration of vascular smooth muscle cells induced by P. gingivalis LPS. Taken together, these results indicate that P. gingivalis LPS promotes the expression of IL-6, which in turn increases the migration of vascular smooth muscle cells.

• International Journal of Oral Biology
• /
• v.43 no.2
• /
• pp.69-76
• /
• 2018

Oral squamous cell carcinoma (OSCC) is the most common type of oral malignancy. Numerous therapies have been proposed for its cure. Research is continually being conducted to develop new forms of treatment as current therapies are associated with numerous side-effects. Luteolin, a common dietary flavonoid, has been demonstrated to possess strong anti-cancer activity against various human cancer cell lines. Nevertheless, research into luteolin-based anticancer activity against oral cancer remains scarce. Thus, the objective of this study was to assess the effect of luteolin as an anti-cancer agent. After treatment with luteolin, Ca9-22 and CAL-27 oral cancer cells showed condensed nuclei and enhanced apoptotic rate with evidence of mitochondria-mediated apoptosis. Epithelialmesenchymal transition (EMT) is closely related to tumor migration and invasion. Luteolin suppressed cancer cell invasion and migration in the current study. Elevated expression of E-cadherin, an adherens junction protein, was evident in both cell lines after luteolin treatment. Luteolin also significantly inhibited transcription factors (i.e., N-cadherin, Slug, Snail, Twist, and ZEB-1) that regulated expression of tumor suppressors such as E-cadherin based on Western blot analysis and quantitative PCR. Thus, luteolin could induce mitochondrial apoptosis and inhibit cancer cell invasion and migration by suppressing EMT-induced transcription factors.

• Journal of Environmental Science International
• /
• v.29 no.9
• /
• pp.885-905
• /
• 2020

This study described the characteristics of the upstream migration of salmon (Chum salmon, Oncorhynchus keta) along Yeon-gok Stream in the eastern coastal region of Korea from October 24 to November 9, 2018 using radio tag and data storage tag loggers for the detection of the locations of tagged salmon and measurement of water temperature. Tracking experiments were conducted and classified into four types (case 1 to case 4) depending on the release time and the number of salmon tracked. Experiments from case 1 to case 3 were classified depending on the number of salmon tracked into cases in which a single tagged salmon was tracked (case 1), a pair of tagged salmon was tracked (case 2), and salmon were tracked by different sex ratios (case 3). Experiments from cases 1 to 3 were conducted between 10 AM and 1 PM, and case 4 was conducted after 3:30 PM. Salmon moved and spawned in the downstream region of the Yeon-gok, where water temperature is higher than in other rivers and salmon return in Canada, Russia, Japan, and the U.S.A. Most of the radio-tagged salmon swam in deep and shaded areas during the day but actively moved upstream close to sunset, regardless of the release time. Females showed relatively more active movements than males during upstream migration.

• International Journal of Stem Cells
• /
• v.16 no.2
• /
• pp.202-214
• /
• 2023

Background and Objectives: To investigate the role of exosomes from periodontal ligament cells (PDLCs) in bone marrow mesenchymal stem cell (BMSC) migration. Methods and Results: Human PDLCs were applied cyclic tension stretching. Exosomes were extracted from cultured PDLCs by ultracentrifugation, then characterized for their size, morphology and protein markers by NTA, TEM and western blotting. The process that PKH26-labeled exosomes taken up by BMSCs was assessed by confocal microscope. BMSC migration was examined by Transwell assay. Exosomes derived from PDLCs were identified. Cyclic tension stretch application on PDLCs can enhance the migration ability of BMSCs through exosomes. The exosomal miRNA expression profiles of unstretched and stretched PDLCs were tested by miRNA microarray. Four miRNAs (miR-4633-5p, miR-30c-5p, miR-371a-3p and let-7b-3p) were upregulated and six (miR-4689, miR-8485, miR-4655-3p, miR-4672, miR-3180-5p and miR-4476) were downregulated in the exosomes after stretching. Sixteen hub proteins were found in the miRNA-mRNA network. Gene Ontology and KEGG pathway analyses demonstrated that the target genes of differentially expressed exosomal miRNAs closely related to the PI3K pathway and vesicle transmission. Conclusions: The exosomes derived from cyclic tension-stretched PDLCs can promote the migration of BMSCs. Alternation of microRNA profiles provides a basis for further research on the regulatory function of the exosomal miRNAs of PDLCs during orthodontic tooth movement.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.16 no.12
• /
• pp.8535-8549
• /
• 2015

The purpose of this study was to examine the life satisfaction of marriage immigrant women in an effort to provide some information on how to offer social support for marriage immigrant women to lead a more satisfaction life. The overall life satisfaction level of the marriage immigrant women was above the average(a mean of 3.40). By age, the women whose husbands were younger were more satisfied. The higher the husband's education, religion appeared higher in cases where the wife is religion, the women who resided in our country for less than five years expressed more life satisfaction. The husband was found in the case of highly professional and white-collar job, the higher the monthly income of the household and when they resided in their own houses. In this context, integrated in terms of international community members to migrant women requires systematic support policies moves forward to global countries.

• Korea journal of population studies
• /
• v.29 no.1
• /
• pp.25-56
• /
• 2006

This study attempts to review the increasing trend in international marriage of Koreans since 1990 and explore the pattern of socio-demographic characteristics of the married couples. This paper develops a conceptual scheme for changing pattern of nuptiality including an increase in international marriage. As the key forces behind the recent increase in international marriage of Koreans, the effects of rapid decline in fertility, rise in sex ratio at birth, urbanward migration of young women, expansion of gender-equity norms, and globalization are stressed. Micro-data from the marriage registration for the period $1990{\sim}2004$ and the divorce registration for the period $2000{\sim}2004$ are utilized. This study focuses on analyzing age at marriage, previous marital experience, education, occupation, and residence of the married couples. Attention is also focused on demographic characteristics of the divorced couples. Results of analyses reveal that there exists a great deal of diversity in international marriage of Koreans. A notable aspect is the profound differences between Korean men and women in the characteristics of their foreign spouses and themselves as well. Another prominent factor emphasized in the analysis is the nationality of foreign spouse. It is indicated that the stereotype of international marriage facilitated by marriage squeeze can be mainly applied to marriages between Korean men and foreign wives from China, southeast Asian countries and the CIS of the old Soviet Union. On the other hand, direct effects of value transformation and globalization are emphasized in the explanation of marriages between Korean men and foreign wives from more developed countries as well as marriages between Korean women and foreign husbands.